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The LPJ-GUESS dynamic vegetation model uniquely combines an individual- and patch-based representation of vegetation dynamics with ecosystem biogeochemical cycling from regional to global scales. We present an updated version that includes plant and soil N dynamics, analysing the implications of accounting for C–N interactions on predictions and performance of the model. Stand structural dynamics and allometric scaling of tree growth suggested by global databases of forest stand structure and development were well reproduced by the model in comparison to an earlier multi-model study. Accounting for N cycle dynamics improved the goodness of fit for broadleaved forests. N limitation associated with low N-mineralisation rates reduces productivity of cold-climate and dry-climate ecosystems relative to mesic temperate and tropical ecosystems. In a model experiment emulating free-air CO2 enrichment (FACE) treatment for forests globally, N limitation associated with low N-mineralisation rates of colder soils reduces CO2 enhancement of net primary production (NPP) for boreal forests, while some temperate and tropical forests exhibit increased NPP enhancement. Under a business-as-usual future climate and emissions scenario, ecosystem C storage globally was projected to increase by ca. 10%; additional N requirements to match this increasing ecosystem C were within the high N supply limit estimated on stoichiometric grounds in an earlier study. Our results highlight the importance of accounting for C–N interactions in studies of global terrestrial N cycling, and as a basis for understanding mechanisms on local scales and in different regional contexts.
We show that, under in vitro conditions, the vulnerability of astroglia to hypoxia is reflected by alterations in endothelin (ET)-1 release and capacity of erythropoietin (EPO) to regulate ET-1 levels. Exposure of cells to 24 h hypoxia did not induce changes in ET-1 release, while 48–72 h hypoxia resulted in increase of ET-1 release from astrocytes that could be abolished by EPO. The endothelin receptor type A (ETA) antagonist BQ123 increased extracellular levels of ET-1 in human fetal astroglial cell line (SV-FHAS). The survival and proliferation of rat primary astrocytes, neural precursors, and neurons upon hypoxic conditions were increased upon administration of BQ123. Hypoxic injury and aging affected the interaction between the EPO and ET systems. Under hypoxia EPO decreased ET-1 release from astrocytes, while ETA receptor blockade enhanced the expression of EPO mRNA and EPO receptor in culture-aged rat astroglia. The blockade of ETA receptor can increase the availability of ET-1 to the ETB receptor and can potentiate the neuroprotective effects of EPO. Thus, the new therapeutic use of combined administration of EPO and ETA receptor antagonists during hypoxia-associated neurodegenerative disorders of the central nervous system (CNS) can be suggested.
The comeback of the Eurasian beaver (Castor fiber) throughout western and central Europe is considered a major conservation success. Traditionally, several subspecies are recognised by morphology and mitochondrial haplotype, each linked to a relict population. During various reintroduction programs in the 20th century, beavers from multiple source localities were released and now form viable populations. These programs differed in their reintroduction strategies, i.e., using pure subspecies vs. mixed source populations. This inhomogeneity in management actions generated ongoing debates regarding the origin of present beaver populations and appropriate management plans for the future. By sequencing of the mitochondrial control region and microsatellite genotyping of 235 beaver individuals from five selected regions in Germany, Switzerland, Luxembourg, and Belgium we show that beavers from at least four source origins currently form admixed, genetically diverse populations that spread across the study region. While regional occurrences of invasive North American beavers (n = 20) were found, all but one C. fiber bore the mitochondrial haplotype of the autochthonous western Evolutionary Significant Unit (ESU). Considering this, as well as the viability of admixed populations and the fact that the fusion of different lineages is already progressing in all studied regions, we argue that admixture between different beaver source populations should be generally accepted.
Recently a considerable amount of effort has been put into quantifying how interactions of the carbon and nitrogen cycle affect future terrestrial carbon sinks. Dynamic vegetation models, representing the nitrogen cycle with varying degree of complexity, have shown diverging constraints of nitrogen dynamics on future carbon sequestration. In this study, we use the dynamic vegetation model LPJ-GUESS to evaluate how population dynamics and resource competition between plant functional types, combined with nitrogen dynamics, have influenced the terrestrial carbon storage in the past and to investigate how terrestrial carbon and nitrogen dynamics might change in the future (1850 to 2100; one exemplary "business-as-usual" climate scenario). Single factor model experiments of CO2 fertilisation and climate change show generally similar directions of the responses of C–N interactions, compared to the C-only version of the model, as documented in previous studies. Under a RCP 8.5 scenario, nitrogen limitation suppresses potential CO2 fertilisation, reducing the cumulative net ecosystem carbon uptake between 1850 and 2100 by 61%, and soil warming-induced increase in nitrogen mineralisation reduces terrestrial carbon loss by 31%. When environmental changes are considered conjointly, carbon sequestration is limited by nitrogen dynamics until present. However, during the 21st century nitrogen dynamics induce a net increase in carbon sequestration, resulting in an overall larger carbon uptake of 17% over the full period. This contradicts earlier model results that showed an 8 to 37% decrease in carbon uptake, questioning the often stated assumption that projections of future terrestrial C dynamics from C-only models are too optimistic.
Mechanics has an important role during morphogenesis, both in the generation of forces driving cell shape changes and in determining the effective material properties of cells and tissues. Drosophila dorsal closure has emerged as a reference model system for investigating the interplay between tissue mechanics and cellular activity. During dorsal closure, the amnioserosa generates one of the major forces that drive closure through the apical contraction of its constituent cells. We combined quantitation of live data, genetic and mechanical perturbation and cell biology, to investigate how mechanical properties and contraction rate emerge from cytoskeletal activity. We found that a decrease in Myosin phosphorylation induces a fluidization of amnioserosa cells which become more compliant. Conversely, an increase in Myosin phosphorylation and an increase in actin linear polymerization induce a solidification of cells. Contrary to expectation, these two perturbations have an opposite effect on the strain rate of cells during DC. While an increase in actin polymerization increases the contraction rate of amnioserosa cells, an increase in Myosin phosphorylation gives rise to cells that contract very slowly. The quantification of how the perturbation induced by laser ablation decays throughout the tissue revealed that the tissue in these two mutant backgrounds reacts very differently. We suggest that the differences in the strain rate of cells in situations where Myosin activity or actin polymerization is increased arise from changes in how the contractile forces are transmitted and coordinated across the tissue through ECadherin-mediated adhesion. Altogether, our results show that there is an optimal level of Myosin activity to generate efficient contraction and suggest that the architecture of the actin cytoskeleton and the dynamics of adhesion complexes are important parameters for the emergence of coordinated activity throughout the tissue.
The Future of the Noosphere
(2014)
In this article, a Koselleckian approach to the issue of time will be employed. In Koselleck's view, modernity has been characterized by a multiplicity of synchronous times, or as Helge Jordheim puts it, by "multiple temporalities". By temporality, Koselleck means something different than epochs or periodizations. More precisely, Jordheim asserts, Koselleck uses this term to reach for experiences of time, such as "progress, decadence, acceleration, or delay, the 'not yet' and the 'no longer', the 'earlier' or 'later than', the 'too early' and the 'too late', situation and the duration". Especially pertinent for this article is Koselleck's category of a horizon of expectations (Erwartungshorizont), understood as perceived prospects for the future. In both the noosphere and the Anthropocene discussion, the notion of an Age of Man seems to merge different timescales into one another, or, as stated by one of the most prominent scientists in the early debate, "The division of historical and geological time is levelled out for us". This article examines the temporality implied in the noosphere concept in order to formulate a specific question regarding the Anthropocene. The article is thus intended to contribute to the on-going examination of the Anthropocene concept by way of historicising its temporality.
Treating large bone defects represents a major challenge in traumatic and orthopedic surgery. Bone tissue engineering provides a promising therapeutic option to improve the local bone healing response. In the present study tissue biocompatibility, systemic toxicity and tumorigenicity of a newly developed composite material consisting of polylactic acid (PLA) and 20% or 40% bioglass (BG20 and BG40), respectively, were analyzed. These materials were seeded with mesenchymal stem cells (MSC) and endothelial progenitor cells (EPC) and tested in a rat calvarial critical size defect model for 3 months and compared to a scaffold consisting only of PLA. Serum was analyzed for organ damage markers such as GOT and creatinine. Leukocyte count, temperature and free radical indicators were measured to determine the degree of systemic inflammation. Possible tumor occurrence was assessed macroscopically and histologically in slides of liver, kidney and spleen. Furthermore, the concentrations of serum malondialdehyde (MDA) and sodium oxide dismutase (SOD) were assessed as indicators of tumor progression. Qualitative tissue response towards the implants and new bone mass formation was histologically investigated. BG20 and BG40, with or without progenitor cells, did not cause organ damage, long-term systemic inflammatory reactions or tumor formation. BG20 and BG40 supported bone formation, which was further enhanced in the presence of EPCs and MSCs.
This investigation reflects good biocompatibility of the biomaterials BG20 and BG40 and provides evidence that additionally seeding EPCs and MSCs onto the scaffold does not induce tumor formation.
Chronic ethanol abuse is known to increase susceptibility to infections after injury, in part, by modification of macrophage function. Several intracellular signalling mechanisms are involved in the initiation of inflammatory responses, including the nuclear factor-κB (NF-κB) pathway. In this study, we investigated the systemic and hepatic effect of chronic ethanol feeding on in vivo activation of NF-κB in NF-κB(EGFP) reporter gene mice. Specifically, the study focused on Kupffer cell proinflammatory cytokines IL-6 and TNF-α and activation of NF-κB after chronic ethanol feeding followed by in vitro stimulation with lipopolysaccharide (LPS). We found that chronic ethanol upregulated NF-κB activation and increased hepatic and systemic proinflammatory cytokine levels. Similarly, LPS-stimulated IL-1 β release from whole blood was significantly enhanced in ethanol-fed mice. However, LPS significantly increased IL-6 and TNF-α levels. These results demonstrate that chronic ethanol feeding can improve the responsiveness of macrophage LPS-stimulated IL-6 and TNF-α production and indicate that this effect may result from ethanol-induced alterations in intracellular signalling through NF-κB. Furthermore, LPS and TNF-α stimulated the gene expression of different inflammatory mediators, in part, in a NF-κB-dependent manner.
Ecocriticism started out in the early 1990s in the framework of American literary studies - in the Anglo sense that equates "America" with the "United States." In fact, the new field's first professional organization, the Association for the Study of Literature and the Environment, was founded as an offshoot of academic interest focused on a particular region of the United States, in the backroom of a casino in Reno, Nevada, during the 1992 annual convention of the Western Literature Association. During its first decade, the bulk of ecocritical attention focused on American literature as shaped by Thoreau and British literature as shaped by Wordsworth - a limited but powerful concentration on nature writing in the genres of poetry, nonfiction prose, and the noveI, with particular attention to Native American literature. By the turn of the millennium, in a story that has by now been told repeatedly, interest in the literature-environment nexus had grown and diversified enough that ecocriticism almost literally exploded into a much broader research area encompassing multiple historical periods (from the Middle Ages to postmodernism), genres (from poetry to the graphic novel and narrative film), and regions: the Caribbean, Latin America, East Asia, and Western Europe all emerged as new areas of ecocritical exploration. New encounters between postcolonial theory and ecocritical analysis proved particularly productive for both fields: linking historical exploration and political ecology with literary analysis, the emergent "poco-eco" matrix opened new perspectives on the connections and disjunctures between imperialism, ecological crisis, and conservation. Over the last few years, the concept of "Environmental Humanities" has increasingly co me to accompany and to superimpose itself as an umbrella term on ecocriticism and comparable research areas in neighboring disciplines: environmental history, environmental anthropology, environmental philosophy, cultural geography, and political ecology. Driven by the impulse to connect environmental research across the humanities, to justify humanistic research at institutions often prone to cut first in the humanities, and to bring the knowledge generated through humanistic research into the public sphere, environmentally oriented scholars have used the term "Environmental Humanities" as a shorthand for what they hope will be a new vision of their discipline. As of this writing, the concept remains somewhat more aspirational than real. While ecocritics and environmental philosophers have long collaborated in Australia, and environmental historians and ecocritics sometimes collaborate in the United States, the disciplines that make up the Environmental Humanities have to date largely pursued their own disciplinary trajectories. But there are signs that the tide may have begun to turn. Various universities and research organizations have started programs in the field. The Swedish environmental historian Sverker Sörlin published a brief outline of the new interdisciplinary matrix in the journal 'BioScience' in 2012, and a longer manifesto followed from the editorial collective of the newly established journal 'Environmental Humanities' at Macquarie University in Australia (Rose et al. 2012). Another journal focusing on the environmental humanities began publication in early 2014 from the University of Oregon under the title 'Resilience'.
The present article analyzes a prominent yet relatively understudied contact space among Native American, New Zealand Maori, and aboriginal Taiwanese literatures: the struggle of indigenous peoples to negotiate optimal relationships between themselves and the natural world, particularly in light of capitalist modernity and globalization. Many indigenous narratives draw sharp distinctions between native peoples and outsiders, predictably portraying the former as protectors and the latter as destroyers of both nature and indigenous local cultures. The Native American Chickasaw writer Linda Hogan's (1947-) novel 'People of the Whale' (2008), the Maori writer Patricia Grace's (1937-) novel 'Patiki' (1986), and the aboriginal Taiwanese writer Topas Tamapima's short story "Zuihou de lieren" are no exception. But these texts also problematize notions of the so-called "ecological native." They do so most conspicuously by revealing the ambiguous relationships those peoples believed closest to nature have with the nonhuman world, that is to say their environmental ambiguity ('ecoambiguity') (Thornber 2012).
Tympanal hearing organs of insects emit distortion-product otoacoustic emissions (DPOAEs) which are indicative of nonlinear mechanical sound processing. General characteristics of insect DPOAEs are comparable to those measured in vertebrates, despite distinct differences in ear anatomy. DPOAEs appear during simultaneous stimulation with two pure tones (f1<f2) as additional spectral peaks at frequencies of nf1-(n-1)f2 and nf2-(n-1)f1, with the 2f1-f2 emission being the most prominent one. Insect DPOAEs are highly vulnerable to manipulations that interfere with the animal's physiological state and disappear after death. First evidence from locusts suggested that scolopidial mechanoreceptors might play a role in frequency-specific DPOAE generation (Möckel et al. 2007). The overall aim of this thesis was to determine the source of sensitive, nonlinear hearing at high frequencies and of DPOAE generation in tympanal organs of insects.
The first project of the present thesis involved general characteristics of DPOAE generation in the bushcricket Mecopoda elongata and the selective exclusion of the scolopidial mechanoreceptors using the neuroactive insectizide pymetrozine (Möckel et al. 2011). Pymetrozin appears to act highly effective and selectively on chordotonal organs, without affecting other sensory organs that lack scolopidial receptors. Pymetrozine solutions were applied as closely as possible to the scolopidia via a cuticle opening in the tibia, distally to the organ. Applications at concentrations between 10-3 and 10-7 M led to a pronounced and irreversible decrease of DPOAE amplitudes. Both this study on bushcrickets (Möckel et al. 2011) and an earlier one on locusts (Möckel et al. 2007) hence indicate the involvement of scolopidia in DPOAE generation in insects, by using complementary methods (pharmacological versus mechanical manipulation) and different animal models.
The second project of the present thesis investigated the temperature-dependence of DPOAEs in the locust Locusta migratoria (Möckel et al. 2012). The suggested biological origin of acoustic two-tone distortions in insects should involve metabolic processes, whose temperature-dependence would directly affect the DPOAE generation. Body temperature shifts resulted in reversible, level- and frequency-dependent effects on the 2f1–f2 emission. Using low f2 frequencies of up to 10 kHz, a body temperature increase (median +8–9°C) led to an upward shift of DPOAE amplitudes of approximately +10 dB, whereas a temperature decrease (median –7°C) was followed by a reduction of DPOAE amplitudes by 3 to 5 dB. Both effects were only present in the range of the low-level component of DPOAE growth functions below f2 stimulus levels of approximately 30-40 dB SPL. Emissions induced by higher stimulus levels and frequencies (e.g. 12 and 18 kHz) remained unaffected by any temperature shifts. The Arrhenius activation energy of the underlying cellular component amounted to 34 and 41 kJmol-1 (for growth functions measured with 8 and 10 kHz as f2, respectively). Such activation energy values provide a hint that an intact dynein-tubulin system within the scolopidial receptors could play an essential part in the DPOAE generation in tympanal organs.
The third project of this thesis demonstrated mechanical DPOAE analogs in the tympanum's vibration pattern during two-tone stimulation in the locust Schistocerca gregaria, using laser Doppler vibrometry (Möckel et al. 2014). DPOAE generation crucially relies on the integrity of the scolopidial mechanoreceptors (Möckel et al. 2007, 2011), which in locusts, directly attach to the tympanal membrane. During two-tone stimulation, DPOAEs were shown to mechanically emerge at the tympanum region where the auditory mechanoreceptors are attached. Those emission-coupled vibrations differed remarkably from tympanum waves evoked by external pure tones of the same frequency, in terms of wave propagation, energy distribution, and location of amplitude maxima. In contrast to traveling wave-like characteristics of externally evoked vibrations, intrinsically generated waves were locally restricted to the region around the high frequency receptors’ attachment position. The mechanical gradient of the tympanal membrane that leads to direction-dependent properties probably avoids the spreading of these locally evoked waves, which are then reflected and occur only in restricted areas as standing waves. Selective inactivation of mechanoreceptors by mechanical lesions did not affect the tympanum's response to external pure tones, but abolished the emission's displacement amplitude peak. These findings provide evidence that tympanal auditory receptors, comparable to the situation in mammals, comprise the required nonlinear response characteristics, which during two-tone stimulation lead to additional, highly localized deflections of the tympanum.
This paper studies the life cycle consumption-investment-insurance problem of a family. The wage earner faces the risk of a health shock that significantly increases his probability of dying. The family can buy term life insurance with realistic features. In particular, the available contracts are long term so that decisions are sticky and can only be revised at significant costs. Furthermore, a revision is only possible as long as the insured person is healthy. A second important and realistic feature of our model is that the labor income of
the wage earner is unspanned. We document that the combination of unspanned labor income and the stickiness of insurance decisions reduces the insurance demand significantly. This is because an income shock induces the need to reduce the insurance coverage, since premia become less affordable. Since such a reduction is costly and families anticipate these potential costs, they buy less protection at all ages. In particular, young families stay away from life insurance markets altogether.
In this paper, we propose a novel approach on how to estimate systemic risk and identify its key determinants. For all US financial companies with publicly traded equity options, we extract their option-implied value-at-risks (VaRs) and measure the spillover effects between individual company VaRs and the option-implied VaR of an US financial index. First, we study the spillover effect of increasing company risks on the financial sector. Second, we analyze which companies are most affected if the tail risk of the financial sector increases. We find that key accounting and market valuation metrics such as size, leverage, balance sheet composition, market-to-book ratio and earnings have a significant influence on the systemic risk profile of a financial institution. In contrast to earlier studies, the employed panel vector autoregression (PVAR) estimator allows for a causal interpretation of the results.
In this essay, one of the most serious problems highlighted with respect to contemporary Iranians, who are mostly known as Shi‘ite-Perso (Shi‘ite-Persian) citizens of Iran, and what their view toward abusing wine and opium is. On one hand, the wealthy Persian literature is full of poems, narrations and notes with reference to wine and opium, while on the other hand, many parts of Shi‘ite-Islamic thought deem wine unclean and illegal, and abusing opium is forbidden except under certain [hard-fulfilling] conditions. Hereby, in this essay the aim is to express why the question “are drinking wine and abusing opium known as addiction or literal culture?” is suspended throughout the young Iranian generation. In this regard, the standpoints of Persian poets and Iranian religious figures towards wine and opium will be considered.
Loudness in the novel
(2014)
The novel is composed entirely of voices: the most prominent among them is typically that of the narrator, which is regularly intermixed with those of the various characters. In reading through a novel, the reader "hears" these heterogeneous voices as they occur in the text. When the novel is read out loud, the voices are audibly heard. They are also heard, however, when the novel is read silently: in this la!er case, the voices are not verbalized for others to hear, but acoustically created and perceived in the mind of the reader. Simply put: sound, in the context of the novel, is fundamentally a product of the novel’s voices. This conception of sound mechanics may at first seem unintuitive—sound seems to be the product of oral reading—but it is only by starting with the voice that one can fully appreciate sound’s function in the novel. Moreover, such a conception of sound mechanics finds affirmation in the works of both Mikhail Bakhtin and Elaine Scarry: "In the novel," writes Bakhtin, "we can always hear voices (even while reading silently to ourselves)."
This paper makes a conceptual contribution to the effect of monetary policy on financial stability. We develop a microfounded network model with endogenous network formation to analyze the impact of central banks' monetary policy interventions on systemic risk. Banks choose their portfolio, including their borrowing and lending decisions on the interbank market, to maximize profit subject to regulatory constraints in an asset-liability framework. Systemic risk arises in the form of multiple bank defaults driven by common shock exposure on asset markets, direct contagion via the interbank market, and firesale spirals. The central bank injects or withdraws liquidity on the interbank markets to achieve its desired interest rate target. A tension arises between the beneficial effects of stabilized interest rates and increased loan volume and the detrimental effects of higher risk taking incentives. We find that central bank supply of liquidity quite generally increases systemic risk.
Panel Sample Selection ModelsThe empirical evidence currently available in the literature regarding the effects of a country's IMF program participation on its output growth is rather inconclusive. In this paper we propose and estimate a panel data sample selection model featuring state dependence. As in this model the output growth effects of program participation can be conditional on the realization of a state variable (conditional pooling), our framework may reconcile previous empirical evidence based on models without state-dependent effects. We find that the effects of IMF program participation on output growth vary systematically with an index reflecting a country's institutional record, and that output growth effects of program participation are significantly positive only if the program participation is coupled with sufficient improvement of the institutional record.
This paper makes a conceptual contribution to the effect of monetary policy on financial stability. We develop a microfounded network model with endogenous network formation to analyze the impact of central banks' monetary policy interventions on systemic risk. Banks choose their portfolio, including their borrowing and lending decisions on the interbank market, to maximize profit subject to regulatory constraints in an asset-liability framework. Systemic risk arises in the form of multiple bank defaults driven by common shock exposure on asset markets, direct contagion via the interbank market, and firesale spirals. The central bank injects or withdraws liquidity on the interbank markets to achieve its desired interest rate target. A tension arises between the beneficial effects of stabilized interest rates and increased loan volume and the detrimental effects of higher risk taking incentives. We find that central bank supply of liquidity quite generally increases systemic risk.
Conviviality in Bellville: An Ethnography of Space, Place, Mobility and Being in Urban South Africa
(2014)
This book provides insight into the experiences of mobility and migration in contemporary South Africa, contributing to a field of literature about multiculturalism and urban public space in globalizing cities. It takes into consideration the greater international political and local socio-economic factors that drive migration, relationships and conviviality, and how they are intertwined in the everyday narrative of 'insiders' and 'outsiders'. The Bellville central business district demonstrates the realities of interconnected local and global hierarchies of citizenship and belonging and how they emerge in a world of accelerated mobility. The book further demonstrates how the emergence of conviviality in everyday public life represents a critical field for contemplating contemporary notions of human rights, citizenship and belonging.
We explore the sources of household balance sheet adjustment following the collapse of the housing market in 2006. First, we use microdata from the Federal Reserve Board’s Senior Loan Officer Opinion Survey to document that banks cumulatively tightened consumer lending standards more in counties that experienced a house price boom in the mid-2000s than in non-boom counties. We then use the idea that renters, unlike homeowners, did not experience an adverse wealth shock when the housing market collapsed to examine the relative importance of two explanations for the observed deleveraging and the sluggish pickup in consumption after 2008. First, households may have optimally adjusted to lower wealth by reducing their demand for debt and implicitly, their demand for consumption. Alternatively, banks may have been more reluctant to lend in areas with pronounced real estate declines. Our evidence is consistent with the second explanation. Renters with low risk scores, compared to homeowners in the same markets, reduced their levels of nonmortgage debt and credit card debt more in counties where house prices fell more. The contrast suggests that the observed reductions in aggregate borrowing were more driven by cutbacks in the provision of credit than by a demand-based response to lower housing wealth.
The history of people with disabilities has been dominated by their isolation and exclusion. The long fight towards inclusion - and inclusive education in particular - started not many years ago. Most were powerless to control their own destiny. Their participation in society has been the object of other's actions. In many countries their disability policies have a substantial element of protection and charity but not the right to equalisation of opportunities. This book highlights the process of change that is underway internationally. The equalisation of opportunities requires new processes through which the various systems of society such as health services and education are delivered. It means the right for people with disabilities to remain in their communities and to receive the schooling and social supports they need within the ordinary structures available in local communities. Strong advocacy is needed for this to happen. In particular parents need to be empowered, communities mobilised and professionals trained in new ways of working: hence this book. Drawing on experiences in Africa, the book describes the issues to be considered when it comes to implementing inclusive strategies: the processes to be followed and the roles of different sectors, such as people with disabilities, parents, policy makers, educationalists, health and community development professionals and crucially, society at large.
We characterize optimal redistribution in a dynastic family model with human capital. We show how a government can improve the trade-off between equality and incentives by changing the amount of observable human capital. We provide an intuitive decomposition for the wedge between human-capital investment in the laissez faire and the social optimum. This wedge differs from the wedge for bequests because human capital carries risk: its returns depend on the non-diversi
able risk of children's ability. Thus, human capital investment is encouraged more than bequests in the social optimum if human capital is a bad hedge for consumption risk.
This thesis is structured into 7 chapters:
• Chapter 2 gives an overview of the ultrashort high intensity laser interaction with matter. The laser interaction with an induced plasma is described, starting from the kinematics of single electron motion, followed by collective electron effects and the ponderamotive motion in the laser focus and the plasma transparency for the laser beam. The three different mechanisms prepared to accelerate and propagate electrons through matter are discussed. The following indirect acceleration of protons is explained by the Target Normal Sheath Acceleration (TNSA) mechanism. Finally some possible applications of laser accelerated protons are explained briefly.
• Chapter 3 deals with the modeling of geometry and field mapping of magnetic lens. Initial proton and electron distributions, fitted to PHELIX measured data are generated, a brief description of employed codes and used techniques in simulation is given, and the aberrations at the solenoid focal spot is studied.
• Chapter 4 presents a simulation study for suggested corrections to optimize the proton beam as a later beam source. Two tools have been employed in these suggested corrections, an aperture placed at the solenoid focal spot as energy selection tool, and a scattering foil placed in the proton beam to smooth the radial energy beam profile correlation at the focal spot due to chromatic aberrations. Another suggested correction has been investigated, to optimize the beam radius at the focal spot by lens geometry controlling.
• Chapter 5 presents a simulation study for the de-neutralization problem in TNSA caused by the fringing fields of pulsed magnetic solenoid and quadrupole. In this simulation, we followed an electrostatic model, wherethe evolution of both, self and mutual fields through the pulsed magnetic solenoid could be found, which is not the case in the quadrupole and only the growth of self fields could be found. The field mapping of magnetic elements is generated by the Matlab program, while the TraceWin code is employed to study the tracking through magnetic elements.
• Chapter 6 describes the PHELIX laser parameters at GSI with chirp pulse amplification technique (CPA), and Gafchromic Radiochromic film RCF) as a spatial energy resolver film detector. The results of experiments with laser proton acceleration, which were performed in two experimental areas at GSI (Z6 area and PHELIX Laser Hall (PLH)), are presented in section 6.3.
• Chapter 7 includes the main results of this work, conclusions and gives a perspective for future experimental activities.
Use of drug-eluting balloon coronary intervention prior to living donor kidney transplantation
(2014)
Background: Kidney transplantation is the gold standard of therapy in patients with terminal renal insufficiency. Living donor transplantation is a well-established option in this field. Enlarging the donor's pool implicates the acceptance of an increased rate of comorbidities. Among them, coronary artery disease is a growing problem. An increasing number of patients, undergoing living donation, receive antiplatelet therapies due to coronary disease.
Case presentation: Here we report about the perioperative treatment with a drug-eluting balloon in a patient with major cardiac risk factors who underwent kidney transplantation.
Conclusion: At the current time no recommendation can be given for the routine use of drug-eluting balloons.
After the Global Financial Crisis a controversial rush to fiscal austerity followed in many countries. Yet research on the effects of austerity on macroeconomic aggregates was and still is unsettled, mired by the difficulty of identifying multipliers from observational data. This paper reconciles seemingly disparate estimates of multipliers within a unified and state-contingent framework. We achieve identification of causal effects with new propensity-score based methods for time series data. Using this novel approach, we show that austerity is always a drag on growth, and especially so in depressed economies: a one percent of GDP fiscal consolidation translates into 4 percent lower real GDP after five years when implemented in the slump rather than the boom. We illustrate our findings with a counterfactual evaluation of the impact of the U.K. government’s shift to austerity policies in 2010 on subsequent growth.
Reaction times to previously ignored information are often delayed, a phenomenon referred to as negative priming (NP). Rothermund et al. (2005) proposed that NP is caused by the retrieval of incidental stimulus-response associations when consecutive displays share visual features but require different responses. In two experiments we examined whether the features (color, shape) that reappear in consecutive displays, or their level of processing (early-perceptual, late-semantic) moderate the likelihood that stimulus-response associations are retrieved. Using a perceptual matching task (Experiment 1), NP occurred independently of whether responses were repeated or switched. Only when implementing a semantic-matching task (Experiment 2), negative priming was determined by response-repetition as predicted by response-retrieval theory. The results can be explained in terms of a task-dependent temporal discrimination process (Milliken et al., 1998): Response-relevant features are encoded more strongly and/or are more likely to be retrieved than irrelevant features.
A 48 year old patient with dilated cardiomyopathy and chronic acne inversa underwent implantation of a LVAD system (Heartmate II, Thoratec, USA) March 2011. During 2011 and 2012 the patient was repeatedly readmitted for treatment of driveline infection with MRSA. Colonization was controlled with Linezolid and Rifampicin however reoccurred after discontinuation. In August 2012 the LVAD-system was exchanged due to pump dysfunction (HVAD, HeartWare Inc., USA). Postoperatively, the patient presented with ascites which secreted through the driveline exit. Consequently, the abdominal wall was surgically corrected to prevent exit of peritoneal fluid through the driveline, and the patient was discharged with sterile wound swabs. However 6 weeks after discharge the driveline exit wound started secreting pus showing abundant growth of multi resistant staphylococcus aureus (MRSA). With clinical signs of increasing liver failure with regular need for paracentesis, and clinical signs of local infection, a CT scan of the abdomen was performed revealing an enrichment of contrast medium along the driveline and an abscess-like formation on the abdominal wall. Patient was admitted receiving regular dose Daptomycin and Rifampicin. The latter was discontinued after ten days. The abscess, surrounding driveline exit and abdominal wall cavity was excised and vacuum treatment initiated. Total duration of Daptomycin therapy was 3 weeks. While first week skin and wound swabs were still positive for MRSA, all samples were sterile after the second week. Inflammation was monitored by leucocyte count and IL6. The secretion of pus along the driveline ceased, the wound cavity was closed subsequently. After discharge and stop of antibiotics skin and driveline swabs remained negative for MRSA (10 weeks).
A multiple filter test for the detection of rate changes in renewal processes with varying variance
(2014)
The thesis provides novel procedures in the statistical field of change point detection in time series.
Motivated by a variety of neuronal spike train patterns, a broad stochastic point process model is introduced. This model features points in time (change points), where the associated event rate changes. For purposes of change point detection, filtered derivative processes (MOSUM) are studied. Functional limit theorems for the filtered derivative processes are derived. These results are used to support novel procedures for change point detection; in particular, multiple filters (bandwidths) are applied simultaneously in oder to detect change points in different time scales.
The work presented in this thesis is devoted to two classes of mathematical population genetics models, namely the Kingman-coalescent and the Beta-coalescents. Chapters 2, 3 and 4 of the thesis include results concerned with the first model, whereas Chapter 5 presents contributions to the second class of models.
FIAS Scientific Report 2013
(2014)
The present paper describes five new species of candonid ostracods in two genera: Pseudocandona agostinhoi sp. nov., P. cillisi sp. nov., P. claudinae sp. nov., Candobrasilopsis elongata sp. nov. and C. acutis sp. nov. The three species of Pseudocandona belong to the caribbeana-group in this genus. With the two new species of Candobrasilopsis, this genus now comprises four species.
Candobrasilopsis elongata sp. nov. is the most common of the five new species described here, while C. acutis sp. nov. and P. claudinae sp. nov. are known from one locality only, which is furthermore the same for both species: a small streamlet entering the Paraná River. With the description of the present five species, the number of species known from the Paraná River alluvial valley, including the Taquaruçu lakes, now amounts to 49.
In this paper, we investigate how the introduction of complex, model-based capital regulation affected credit risk of financial institutions. Model-based regulation was meant to enhance the stability of the financial sector by making capital charges more sensitive to risk. Exploiting the staggered introduction of the model-based approach in Germany and the richness of our loan-level data set, we show that (1) internal risk estimates employed for regulatory purposes systematically underpredict actual default rates by 0.5 to 1 percentage points; (2) both default rates and loss rates are higher for loans that were originated under the model-based approach, while corresponding risk-weights are significantly lower; and (3) interest rates are higher for loans originated under the model-based approach, suggesting that banks were aware of the higher risk associated with these loans and priced them accordingly. Further, we document that large banks benefited from the reform as they experienced a reduction in capital charges and consequently expanded their lending at the expense of smaller banks that did not introduce the model-based approach. Counter to the stated objectives, the introduction of complex regulation adversely affected the credit risk of financial institutions. Overall, our results highlight the pitfalls of complex regulation and suggest that simpler rules may increase the efficacy of financial regulation.
Soil water potential is crucial to plant transpiration and thus to carbon cycling and biosphere–atmosphere interactions, yet it is difficult to measure in the field. Volumetric and gravimetric water contents are easy and cheap to measure in the field, but can be a poor proxy of plant-available water. Soil water content can be transformed to water potential using soil moisture retention curves. We provide empirically derived soil moisture retention curves for seven soil types in the Kruger National Park, South Africa. Site-specific curves produced excellent estimates of soil water potential from soil water content values. Curves from soils derived from the same geological substrate were similar, potentially allowing for the use of one curve for basalt soils and another for granite soils. It is anticipated that this dataset will help hydrologists and ecophysiologists understand water dynamics, carbon cycling and biosphere–atmosphere interactions under current and changing climatic conditions in the region.
Mohammad Arkoun (٭1928, Algeria; †2010, Paris) was an influential Muslim intellectual and particularly concerned with - amongst a profound spectrum of scholarly interests – reforming the academic study of Islamic societies. Trained at the University of Algiers (Faculty of Philology) he ventured off to lecture Arab language and literature at the Sorbonne. His engagement with philosophy and sociology led in 1968 to his PhD at the Sorbonne through a work on Ibn Miskawayh’s ethics...
This exploration into Arkoun’s stances on the Quran looks onto the genesis of the Quran, the notion of the Quran as the ‘deliverer of truth’, and with that, its significane for the ‘being in the world’ of Muslim societies. I will also point out some crucial difficulties in the study of Arkoun’s views on the Quran as well as their implications for the study of Islamic cultures.
Riley (1979)'s reactive equilibrium concept addresses problems of equilibrium existence in competitive markets with adverse selection. The game-theoretic interpretation of the reactive equilibrium concept in Engers and Fernandez (1987) yields the Rothschild-Stiglitz (1976)/Riley (1979) allocation as an equilibrium allocation, however multiplicity of equilibrium emerges. In this note we imbed the reactive equilibrium's logic in a dynamic market context with active consumers. We show that the Riley/Rothschild-Stiglitz contracts constitute the unique equilibrium allocation in any pure strategy subgame perfect Nash equilibrium.
Carinostoma elegans new to the Slovakian harvestmen fauna (Opiliones, Dyspnoi, Nemastomatidae)
(2014)
A new genus and species of small harvestman was found for the first time in Slovakia – Carinostoma elegans (Sorensen, 1894). One male and two females were collected in the Mlyňany arboretum of the Slovak Academy of Science (western Slovakia). Descriptions and photographs of both sexes of C. elegans are provided. Additional comments, and a map of distribution of all species of this genus, are provided.
In this article, the author shows that progress of info-communications is a key factor of society changes, as it radically changes the key aspects of human life. Studying the time of progress and comparing it with the most important anthropic characteristic - length of human life, he comes to the conclusion that our generation has witnessed the tipping point in the rate of development of human civilization. This showing up in the fact that the present stage of the scientific and technological advance lead to the transformation, perhaps on the same scale, what were the appearance of written language and publishing, but these multiple fundamental changes in the life of society occur within the life of a single generation. In these circumstances, the task of forecasting, in its traditional setting, is becoming increasingly inaccurate. According to the author, the only possibility is to venture outside the framework of formal logic and technocratic approaches and try to find answers to these questions by generating new meanings of the realities surrounding us and in this context philosophy has a special role.
The spitting spider Scytodes fusca Walckenaer, 1837 is recorded for the first time in Central Europe from both Germany and Slovakia. The species was found in two localities, within the Botanical Garden in Bratislava (Slovakia), specifically from a heated greenhouse with high humidity, and the "Tropical Islands", a tropical holiday resort in Krausnick (Germany). It seems that this Pantropical species has probably been introduced here along with imported plants. A description of diagnostic characters, as well as figures, is given.
We have isolated a cDNA coding for a putative invertebrate-type dopamine receptor (Peadop2) from P. americana brain by using a PCR-based strategy. The mRNA is present in samples from brain and salivary glands. We analyzed the distribution of the PeaDOP2 receptor protein with specific affinity-purified polyclonal antibodies. On Western blots, PeaDOP2 was detected in protein samples from brain, subesophageal ganglion, thoracic ganglia, and salivary glands. In immunocytochemical experiments, we detected PeaDOP2 in neurons with their somata being located at the anterior edge of the medulla bilaterally innervating the optic lobes and projecting to the ventro-lateral protocerebrum. In order to determine the functional and pharmacological properties of the cloned receptor, we generated a cell line constitutively expressing PeaDOP2. Activation of PeaDOP2-expressing cells with dopamine induced an increase in intracellular cAMP. In contrast, a C-terminally truncated splice variant of this receptor did not exhibit any functional property by itself. The molecular and pharmacological characterization of the first dopamine receptor from P. americana provides the basis for forthcoming studies focusing on the significance of the dopaminergic system in cockroach behavior and physiology.
Increased oxidative stress and reduced nitric oxide (NO) bioavailability play a causal role in endothelial cell dysfunction occurring in the vasculature of diabetic patients. In this review, we summarized the molecular mechanisms underpinning diabetic endothelial and vascular dysfunction. In particular, we focused our attention on the complex interplay existing among NO, reactive oxygen species (ROS), and one crucial regulator of intracellular ROS production, p66Shc protein.
This paper contrasts the recent European initiatives on regulating corporate groups with alternative approaches to the phenomenon. In doing so it pays particular regard to the German codified law on corporate groups as the polar opposite to the piecemeal approach favored by E.U. legislation.
It finds that the European Commission’s proposal to submit (significant) related party transactions to enhanced transparency, outside fairness review, and ex ante shareholder approval is both flawed in its design and based on contestable assumptions on informed voting of institutional investors. In particular, the contemplated exemption for transactions with wholly owned subsidiaries allows controlling shareholders to circumvent the rule extensively. Moreover, vesting voting rights with (institutional) investors will not lead to the informed assessment that is hoped for, because these investors will rationally abstain from active monitoring and rely on proxy advisory firms instead whose competency to analyze non-routine significant related party transactions is questionable.
The paper further delineates that the proposed recognition of an overriding interest of the group requires strong counterbalances to adequately protect minority shareholders and creditors. Hence, if the Commission choses to go down this route it might end up with a comprehensive regulation that is akin to the unpopular Ninth Company Law Directive in spirit, though not in content. The latter prediction is corroborated by the pertinent parts of the proposal for a European Model Company Act.
Background: Cichlid fishes show considerable diversity in swim bladder morphology. In members of the subfamily Etroplinae, the connection between anterior swim bladder extensions and the inner ears enhances sound transmission and translates into an improved hearing ability. We tested the hypothesis that those swim bladder modifications coincide with differences in inner ear morphology and thus compared Steatocranus tinanti (vestigial swim bladder), Hemichromis guttatus (large swim bladder without extensions), and Etroplus maculatus (intimate connection between swim bladder and inner ears).
Methodology and results: We applied immunostaining together with confocal imaging and scanning electron microscopy for the investigation of sensory epithelia, and high-resolution, contrast-enhanced microCT imaging for characterizing inner ears in 3D, and evaluated otolith dimensions. Compared to S. tinanti and H. guttatus, inner ears of E. maculatus showed an enlargement of all three maculae, and a particularly large lacinia of the macula utriculi. While our analysis of orientation patterns of ciliary bundles on the three macula types using artificially flattened maculae uncovered rather similar orientation patterns of ciliary bundles, interspecific differences became apparent when illustrating the orientation patterns on the 3D models of the maculae: differences in the shape and curvature of the lacinia of the macula utriculi, and the anterior arm of the macula lagenae resulted in an altered arrangement of ciliary bundles.
Conclusions: Our results imply that improved audition in E. maculatus is associated not only with swim bladder modifications but also with altered inner ear morphology. However, not all modifications in E. maculatus could be connected to enhanced auditory abilities, and so a potential improvement of the vestibular sense, among others, also needs to be considered. Our study highlights the value of analyzing orientation patterns of ciliary bundles in their intact 3D context in studies of inner ear morphology and physiology.
The Virgin Islands (except St. Croix) are geologically part of the Puerto Rico Bank and biologically related to Puerto Rico, but their cockroaches (Dictyoptera: Blattaria) were not yet as well studied as those on Puerto Rico. To elucidate the number of species, life history, range distribution, and seasonal abundance of these cockroaches, we have conducted a quantitative study since June 2000 using a Malaise trap on Guana Island, British Virgin Islands, in addition to other conventional collecting methods. We found 21 species: Blattella germanica (Linnaeus), Cariblatta antiguensis (Saussure and Zehntner), Cariblatta sp. 2, Cariblatta sp. 3, Colapteroblatta sp. 1, Eurycotis improcera Rehn, Eurycotis sp. 2, Euthlastoblatta facies (Walker), Hemiblabera brunneri (Saussure), Nyctibora lutzi Rehn and Hebard, Panchlora sagax Rehn and Hebard, Periplaneta americana (Linnaeus), P. australasiae (Fabricius), Plectoptera infulata Rehn and Hebard, P. rhabdota Rehn and Hebard, Plectoptera sp. 3, Pycnoscelus surinamensis (Linnaeus), Symploce pararufi collis Roth, S. rufi collis (Fabricius), polyphagid sp. 1 (Compsodes sp. 1), and polyphagid sp. 2. Among them, nine are new records for the Virgin Islands and fi ve for Guana Island. In addition, Euthlastoblatta diaphana (Fabricius), Nyctibora noctivaga Rehn, Panchlora nivea (Linnaeus), P. viridis (Fabricius), and Rhyparobia maderae (Fabricius) were recorded historically but were not rediscovered. As a result, the number of species is increased from 17 to 26 for the Virgin Islands, and from 10 to 15 for Guana Island. Overall, only fi ve species are edifi carian and likely introduced. Nymphs of polyphagid sp. 2 and Euthlastoblatta facies are reported for the fi rst time as dwellers in termite runways. Only eight species came to the Malaise trap; their phenology illustrates close but not necessarily synchronic relationship with both the timing and amount of rainfall. Monthly abundance showed spring and fall highs and summer and winter lows. Yearly abundance reached lows when annual rainfall decreased below a threshold average of 2.0 mm per day. Seasonality and response to drought varied among species. This paper lays a foundation for further research on diversity of cockroaches from the Virgin Islands and their relationships with those from Puerto Rico.
The ( J, T ) = (1, 1) parity doublet in 20Ne at 11.26 MeV is a good candidate to study parity violation in nuclei. However, its energy splitting is known with insufficient accuracy for quantitative estimates of parity violating effects. To improve on this unsatisfactory situation, nuclear resonance fluorescence experiments using linearly and circularly polarized γ -ray beams were used to determine the energy difference of the parity doublet E = E(1−) − E(1+) = −3.2(±0.7)stat( +0.6 −1.2)sys keV and the ratio of their integrated cross sections I (+) s,0 /I (−) s,0 = 29(±3)stat( +14 −7 )sys. Shell-model calculations predict a parityviolating matrix element having a value in the range 0.46–0.83 eV for the parity doublet. The small energy difference of the parity doublet makes 20Ne an excellent candidate to study parity violation in nuclear excitations.
This paper deals with the control exerted by the mitochondrial translocator FLX1, which catalyzes the movement of the redox cofactor FAD across the mitochondrial membrane, on the efficiency of ATP production, ROS homeostasis, and lifespan of S. cerevisiae. The deletion of the FLX1 gene resulted in respiration-deficient and small-colony phenotype accompanied by a significant ATP shortage and ROS unbalance in glycerol-grown cells. Moreover, the flx1Δ strain showed H2O2 hypersensitivity and decreased lifespan. The impaired biochemical phenotype found in the flx1Δ strain might be justified by an altered expression of the flavoprotein subunit of succinate dehydrogenase, a key enzyme in bioenergetics and cell regulation. A search for possible cis-acting consensus motifs in the regulatory region upstream SDH1-ORF revealed a dozen of upstream motifs that might respond to induced metabolic changes by altering the expression of Flx1p. Among these motifs, two are present in the regulatory region of genes encoding proteins involved in flavin homeostasis. This is the first evidence that the mitochondrial flavin cofactor status is involved in controlling the lifespan of yeasts, maybe by changing the cellular succinate level. This is not the only case in which the homeostasis of redox cofactors underlies complex phenotypical behaviours, as lifespan in yeasts.
Among the 125 currently recognized species of the panoceanic genus Leucothoe, L. antarctica was described in 1888 from the Antarctic seas, but was soon synonymized with the so-called cosmopolitan Leucothoe spinicarpa Abildgaard, which was cited from the Southern Ocean about 70 times since this first record. After erecting a new Antarctic species again only in 1983, “morphological variants” were observed and discussed. In this paper, we revalidate the first defined Antarctic species (Leucothoe antarctica), redescribe the second one (L. orkneyi), describe 5 new Southern Ocean species (L. campbelli sp. nov., L. longimembris sp. nov., L. macquariae sp. nov., L. merletta sp. nov. and L. weddellensis sp. nov.) and provide a key to all Antarctic and sub-Antarctic species.
One memorable quote from Karl Marx’s conception of religion is, “religion is the opium of the masses.” By this, he critiqued religion as an analgesic that dulls the senses, thus inducing a false sense of satisfaction, and preventing the oppressed from revolting against the grubby socio-economic system. As the sigh of the oppressed, religion makes them to resign to fate since it only gives an unrealistic eschatological hope. Rather than conceive religion from this prismatic way, contemporary events have shown that religion has become an amphetamine or a catalyst for revolt, not only at the global but also national level. This work argues that religion is used as an amphetamine, an energizing pill, to pursue other goals than religious as depicted in the activities of Boko Haram sect, which has raised security challenges in contemporary Nigeria.
Recent data on status and distribution of resident and migrant birds in the Cape Verde Islands are presented, including records of nine taxa new to the archipelago, viz. Ciconia nigra, Ciconia ciconia, Circus macrourus, Falco naumanni, Chlidonias hybrida, Chlidonias leucopterus, Apus affinis, Ptyonoprogne fuligula and Phylloscopus inornatus. Also presented are data on a number of breeding taxa, including the first record of the endemic Cape Verde purple heron Ardea bournei outside Santiago island. The alarming situation of the magnificent frigatebird Fregata magnificens, of which only three individuals remain in Cape Verde, constituting the entire population in the East Atlantic, remains of great concern. Several species of birds of prey are also highly threatened and have already become extinct in some islands. Following its expansion through Northwest Africa and the Canary Islands, Eurasian collared dove Streptopelia decaocto has now also become established in at least three of the Cape Verde Islands.
Natural products (NPs) have been a rich source for pharmaceutically used anti-infectives and other drugs. However, the application of anti-infectives inevitably causes the development of resistant and multiresistant pathogens, which have to be treated with novel anti-infectives. The industrial research for novel anti-infectives has been concentrating on members of the bacterial Actinomycetales for a long time. Due to several reasons, e.g. the rediscovery of already known NPs, pharmaceutical companies abandoned their NP-research and focused on drug development based on combinatorial chemistry. However, the limited structural diversity of merely synthetic compound libraries has not been a fruitful source for bioactive compounds. Hence the discovery of novel bioactive NPs as a source for anti-infectives is still of economical and humanitarian interest and will remain to be an important branch of research in the future. One strategy to circumvent the rediscovery of bioactive NPs is the analysis of yet unexplored bacterial taxa. Based on this assumption, this work aimed at the discovery of novel NPs from the entomopathogenic bacterial genera Xenorhabdus and Photorhabdus and other promising taxa, as well as the investigation of their biosynthesis. ...
Acceleration of Biomedical Image Processing and Reconstruction with FPGAs
Increasing chip sizes and better programming tools have made it possible to increase the boundaries of application acceleration with reconfigurable computer chips. In this thesis the potential of acceleration with Field Programmable Gate Arrays (FPGAs) is examined for applications that perform biomedical image processing and reconstruction. The dataflow paradigm was used to port the analysis of image data for localization microscopy and for 3D electron tomography from an imperative description towards the FPGA for the first time.
After the primitives of image processing on FPGAs are presented, a general workflow is given for analyzing imperative source code and converting it to a hardware pipeline where every node processes image data in parallel. The theoretical foundation is then used to accelerate both example applications. For localization microscopy, an acceleration of 185 compared to an Intel i5 450 CPU was achieved, and electron tomography could be sped up by a factor of 5 over an Nvidia Tesla C1060 graphics card while maintaining full accuracy in both cases.
This thesis presents experimental studies of proton capture and fragmentation reactions with heavy-ion storage rings. In one experiment, the 96Ru(p, γ)97Rh cross sections near the Gamow window have been measured at the ESR of GSI. In the other experiment, the measurement of the fragmentation yields has been carried out at the CSRe of IMP.
It is essential to determine the cross sections of (γ, p) or (p, γ) reactions for p-process network calculations. However, only very few of the required cross sections have been measured and thus most of them rely solely on Hauser-Feshbach model predictions. The predictions of the model have always very large uncertainties because of the not well-known input parameters. These parameters can be constrained by experiments. Compared to the traditional activation technique, a novel method using a storage ring has been developed to measure the cross sections of (p, γ) reactions in inverse kinematics.
This proton capture experiment has been performed at the ESR, where the circulating 96Ru44+ ions interacted with a hydrogen gas target at 9, 10 and 11 MeV/u. The nuclear reaction products of (p, p), (p, α), (p, n) and (p, γ) reactions were registered by position sensitive detectors. A Geant4 simulation code has been developed to distinguish the (p, γ) reaction products unambiguously from the background reactions. In this work, a relative normalization method has been utilized to accurately determine the cross sections of the (p, γ) reaction. The 96Ru(p, γ)97Rh cross section in the Gamow window of the p process is sensitive to two parameters, i.e., the γ-ray strength function and the optical model potential, while it is mainly sensitive to the γ-ray strength function in the energy region of our experiment. Therefore, our experimental (p, γ) cross sections near 10 MeV/u have been used to directly constrain the γ-ray strength function used in the model. Furthermore, the proton potential has also been constrained by combining our results with additional experimental data for this reaction in the lower energy region. The constrained model has been used to calculate the reaction rate over a wide temperature range, which is an extremely important input for astrophysical calculations.
The yields of fragments produced by 78Kr fragmentation reactions have been measured at the CSRe for the Tz = −1/2 and Tz = 1/2 nuclei along or close to the paths of αp- and rp-processes. The measured yields present a significant odd-even staggering effect for Tz = −1/2 nuclides but they are small for Tz = 1/2 nuclides.
The magnitude of this effect for four consecutive yields has been quantified using a third-order difference formula. It is found that the largest odd-even staggering is reached near the closed shells Z = 20 and Z = 28. Our experimental results could also compared with the data from other experiments with different projectile-target combinations. All these experimental data strongly support the closed shells Z = 20 and Z = 28 for the Tz = −1/2 nuclei.
As part of a wider study of floodplain vegetation along the River Murray, we carried out a field survey in 1987–1988 involving collection of floristic and vegetation condition data from 335 sample plots (each 400 m2 in area), between Hume Dam and Lake Alexandrina (including the Edward-Wakool anabranch system). The floodplain vegetation is dominated by just two tree species, River Red Gum (Eucalyptus camaldulensis) and Black Box (Eucalyptus largiflorens), but the composition of the understorey shows much greater variation, both along the river and across the floodplain. A total of 499 plant species, subspecies and varieties were recorded from the survey plots, of which 316 (63%) were native and 183 (37%) were exotic. From analysis of the floristic data we identified 37 vegetation communities, not including the vegetation of permanent wetlands and cleared areas; 21 communities were distinguished in the River Red Gum zone, 12 communities in the Black Box zone, and 4 communities on rises within the floodplain. The main floristic division among the River Red Gum communities was between Riverine Plain/ Headwaters Zone communities of the upper Murray, and Mallee Zone communities of the lower Murray. Among the Black Box communities, the main floristic division was between inner floodplain communities and outer floodplain communities, with a further division between South Australian communities and New South Wales/Victorian communities. Major factors influencing the floristic patterns included flooding frequency/duration and soil salinity.
Eucalypt health declined steadily downstream and was poorest in the lower reaches of the river below the Darling Junction, where 60% of the trees were healthy, 18% unhealthy (at least 40% of the canopy dead) and 22% dead. By comparison, at the upper end of the river, above Tocumwal, 84% of the trees were healthy, 14% unhealthy and only 2% dead. Overall, the condition of Black Box trees (44% unhealthy or dead) was worse than the condition of River Red Gum trees (29% unhealthy or dead). Eucaypt regeneration was also poorest below the Darling Junction, with regenerants present in 77% of plots upstream of the Darling but only 35% of plots downstream. The findings of poor tree health and sparse regeneration below the Darling coincide with the most heavily regulated part of the Murray, where the reduction in flooding due to upstream storages and water extraction, mainly for irrigation, has been greatest. Black Box regeneration was much sparser overall than River Red Gum regeneration (regenerants present in 69% of River Red Gum plots but only 29% of Black Box plots). The poor condition of the Black Box trees, coupled with their poor regeneration, suggests that the long-term future of this species along the Murray, particularly below the Darling Junction, is tenuous, even though it is a dominant component of the vegetation.
The integrity of floodplain vegetation along the Murray has been severely compromised by weed invasion. Weeds were common throughout the survey area, but were most prevalent in the climatically wetter sections of the river, at both the downstream and upstream ends (below Mannum and above Tocumwal). The median number of exotic species per plot equalled or exceeded the number of native species in these sections of the river, whereas native species outnumbered exotic species in the other river sections. Communities of the River Red Gum zone and the rises were generally weedier than those of the Black Box zone. Exotic species strongly influenced the community classification. They were the dominant overstorey species in two communities (Salix species – willows) and outnumbered native species in the understorey of another eight communities. At the lower end of the river, below Mannum, the River Red Gums that originally fringed the river had been mostly replaced by dense thickets of the exotic Weeping Willow, Salix babylonica.
Other factors that have impacted on the floodplain vegetation at the plant community level have been river regulation and soil salinisation. Stabilization of water levels in the lower Murray by construction of a series of weirs and barrages has favoured the spread of some communities at the expense of others. The favoured communities, which are characterised by stands of Common Reed, Phragmites australis, along the water’s edge, appear to be artefacts of river regulation. Salinisation has resulted in death of eucalypts and replacement of eucalypt communities by shrub communities dominated by samphires, Tecticornia species. The samphire community characteristic of the most saline sites is one of the most species-poor communities on the Murray floodplain.
Logging along the Murray in New South Wales and Victoria has resulted in extensive replacement of old growth River Red Gum forests and woodlands by more even-aged stands of straight young trees. Following the recent conversion of many areas of State Forest along the Murray in both New South Wales and Victoria to National Park or Regional Park, and thus the cessation of logging in these areas, they should now revert gradually to mature forest and woodland.
This study is the first to describe broad scale floristic patterns in the floodplain vegetation of the Murray covering most of the length of the river. It also provides data on the vegetation condition in the 1980s, and provides a benchmark of conditions before the prolonged Millenium Drought in south-eastern Australia from 1997 to 2010. More recent surveys of vegetation condition have reported a severe decline in tree health during the drought. The results from our 1987–88 survey are important because they show that the deteriorating condition of the vegetation was already evident in the 1980s and although exacerbated by the subsequent drought, it is not just a consequence of that drought. The results are consistent with the conclusion that the primary cause of the decline has been river regulation and water extraction for irrigation. The rate of deterioration has increased rapidly since the 1980s because of the drought. There has been some improvement since the breaking of the drought, but the poor condition of the River Murray floodplain vegetation, an Australian icon, remains a major conservation and management issue. The impacts of climate change – higher temperatures and reduced rainfall – have compounded the problem and will continue to do so at an increasing rate. The results of the study support listing of the floodplain vegetation of the lower reaches of the river as a critically endangered ecological community.
The exact pathophysiology of contrast-induced nephropathy (CIN) is not fully clarified, yet the osmotic characteristics of contrast media (CM) have been a significant focus in many investigations of CIN. Osmotic effects of CM specific to the kidney include transient decreases in blood flow, filtration fraction, and glomerular filtration rate. Potentially significant secondary effects include an osmotically induced diuresis with a concomitant dehydrating effect. Clinical experiences that have compared the occurrence of CIN between the various classes of CM based on osmolality have suggested a much less than anticipated advantage, if any, with a lower osmolality. Recent animal experiments actually suggest that induction of a mild osmotic diuresis in association with iso-osmolar agents tends to offset potentially deleterious renal effects of high viscosity-mediated intratubular CM stagnation.
This thesis serves two main purposes:
1. The introduction of a novel experimental method to investigate phase change dynamics of supercooled liquids
2. First-time measurements for the crystallization behaviour for hydrogen isotopes under various conditions
1) The new method is established by the synergy of a liquid microjet of ~ 5 µm diameter and a scattering technique with high spatial resolution, here linear Raman spectroscopy. Due to the high directional stability and the known velocity of the liquid filament, its traveling axis corresponds to a time axis static in space. Utilizing evaporative cooling in a vacuum environment, the propagating liquid cools down rapidly and eventually experiences a phase transition to the crystalline state. This temporal evolution is probed along the filament axis, ultimately resulting in a time resolution of 10 ns. The feasibility of this approach is proven successfully within the following experiments.
2) A main object of study are para-hydrogen liquid filaments. Raman spectra reveal a temperature gradient of the liquid across the filament. This behaviour can quantitatively be reconstructed by numerical simulations using a layered model and is rooted in the effectiveness of evaporative cooling on the surface and a finite thermal conductivity. The deepest supercoolings achieved are ~ 30% below the melting point, at which the filament starts to solidify from the surface towards the core. With a crystal growth velocity extracted from the data the appropriate growth mechanism is identified. The crystal structure that initially forms is metastable and probably the result of Ostwald’s rule of stages. Indications for a transition within the solid towards the stable equilibrium phase support this interpretation.
The analog isotope ortho-deuterium is evidenced to behave qualitatively similar with quantitative differences being mass related.
In further measurements, isotopic mixtures of para-hydrogen and ortho-deuterium are investigated. It is found that the crystallization process starts earlier and lasts significantly longer compared to the pure substances with the maximum values between 20-50% ortho-deuterium content. A solely temperature based explanation for this effect can be excluded. The difference in the quantum character and hence effective size of the isotopes suggests a strong influence of the progressing liquid-solid-interface. Small dilutions of each para-hydrogen and ortho-deuterium with neon show an even more extended crystallization process compared to above isotopic mixtures. Additionally, the crystal is strongly altered in favor of the equilibrium lattice structure of neon.
King of the Jungle
(2014)
In King of the Jungle, the bouts of ethno-religious violence in Jos are fused with the heartbreaking story of two brothers who go through life unaware of each other's existence. Carefully crafted with local colour which evokes memories of pre-2001 Jos, Bizuum Yadok's first novel weaves humour, urban realism, tragedy and redemption.
The growing role of IT in real estate asset management – the appraisal process as a master sample
(2014)
In the second half of February 2014, Odonata were searched for nine days on Bali andfour days on Lombok, the western Lesser Sundas, Indonesia. One species, Orthetrum chrysishas been for the first time recorded for Bali and six species, Nosostictaemphyla, Idionyx murcia, Brachydiplax chalybea, Agrionoptera insignis, Neurothemisramburii, Rhyothemis phyllishave been for the first time recorded for Lombok. The previous lit-erature concerning the two islands is analysed. To the moment, 55 Odonata species (3 unidentified) are known for Bali and 39 for Lombok, although the actual faunas of both islands are supposed to be equally rich, and further studies on Lombok are necessary. Odonata faunas of Bali and Lombok mirror each other in respect of high shares,29 and 23%, of Odonata species ranging to the west and east of the two islands, respectively. Efficiency of Lombok Strait as a biogeographical boundary was estimated as high as 0.6, so Wallace Line is of importance for Odonata. Some diagnostic characters of N. emphyla, N. ramburii, R. phyllis phyllisand Procordulia sambawanaand a taxo-nomical situation around Prodasineura autumnalisand P. humeralis, which is not justified biogeographically, are discussed. Short notes on habitats and assemblages of Odonata are added.
In this paper, we study the effect of proportional transaction costs on consumption-portfolio decisions and asset prices in a dynamic general equilibrium economy with a financial market that has a single-period bond and two risky stocks, one of which incurs the transaction cost. Our model has multiple investors with stochastic labor income, heterogeneous beliefs, and heterogeneous Epstein-Zin-Weil utility functions. The transaction cost gives rise to endogenous variations in liquidity. We show how equilibrium in this incomplete-markets economy can be characterized and solved for in a recursive fashion. We have three main findings. One, costs for trading a stock lead to a substantial reduction in the trading volume of that stock, but have only a small effect on the trading volume of the other stock and the bond. Two, even in the presence of stochastic labor income and heterogeneous beliefs, transaction costs have only a small effect on the consumption decisions of investors, and hence, on equity risk premia and the liquidity premium. Three, the effects of transaction costs on quantities such as the liquidity premium are overestimated in partial equilibrium relative to general equilibrium.
This is the first English edition of Tamara Mcheidze's monograph on the spiders of Georgia (Mcheidze 1997; in alternative transliteration: Mkheidze 1997), containing taxonomic, faunistic and ecological information on 362 spider species recorded by T. Mcheidze in Georgia between the 1920s and 1992. The English edition resembles the original text, with a preface, taxonomic comments and a part with supplementary information on the locations, a location map and an index provided by the editor.
The rediscovery of an older available name threatens the stability of the long accepted name of Strategus oblongus (Palisot de Beauvois, 1807) (Coleoptera: Scarabaeidae) from Hispaniola. Using Article 23.9 of the International Code of Zoological Nomenclature, Scarabaeus monoceros Nicolson, 1776 is designated a nomen oblitum to maintain nomenclatural stability while its junior synonym, Scarabaeus oblongus Palisot de Beauvois, 1807, is designated a nomen protectum.
OBJECTIVES: Outcome of aortic valve replacement may be influenced by the choice of bioprosthesis. Pericardial heart valves are described to have a favourable haemodynamic profile compared with porcine valves, although the clinical notability of this finding is still controversially debated. Herein, we compared the long-term results of two commonly implanted bioprosthesis at a single centre.
METHODS: All consecutive patients undergoing isolated aortic valve replacement with either a Carpentier-Edwards Magna pericardial prosthesis or a Medtronic Mosaic porcine prosthesis between 2002 and 2008 were analysed regarding preoperative characteristics, short- and long-term survival, valve-related complications and echocardiographic findings.
RESULTS: The Medtronic Mosaic was implanted in 163 patients and the Carpentier-Edwards Magna in 295 patients. The sizes of implanted valves were 22.4 ± 1.5 mm for the Mosaic and 21.8 ± 1.8 mm for the Magna (P = 0.001). The long-term survival rate was 76 and 56% after 5 and 10 years for the Medtronic Mosaic, which was comparable with the Carpentier-Edwards Magna (77 and 57%; P = 0.92). Overall long-term survival was comparable with an age- and sex-matched Austrian general population for both groups. Valve-related adverse events were similar between groups. The postoperative mean transvalvular gradient was significantly increased in the Mosaic group (24 ± 9 mmHg vs 17 ± 7 mmHg; P < 0.001).
CONCLUSIONS: Both types of aortic bioprostheses offer excellent results after isolated aortic valve replacement. Despite relevant differences in gradients, long-term survival was comparable with the expected normal survival for both bioprostheses. Patients with a porcine heart valve had a higher postoperative transvalvular gradient.
Research in the field of Digital Humanities, also known as Humanities Computing, has seen a steady increase over the past years. Situated at the intersection of computing science and the humanities, present efforts focus on making resources such as texts, images, musical pieces and other semiotic artifacts digitally available, searchable and analysable. To this end, computational tools enabling textual search, visual analytics, data mining, statistics and natural language processing are harnessed to support the humanities researcher. The processing of large data sets with appropriate software opens up novel and fruitful approaches to questions in the traditional humanities. This report summarizes the Dagstuhl seminar 14301 on “Computational Humanities - bridging the gap between Computer Science and Digital Humanities”.
1998 ACM Subject Classification I.2.7 Natural Language Processing, J.5 Arts and Humanities
A measurement of the transverse momentum spectra of jets in Pb-Pb collisions at sNN−−−√=2.76 TeV is reported. Jets are reconstructed from charged particles using the anti-kT jet algorithm with jet resolution parameters R of 0.2 and 0.3 in pseudo-rapidity |η|<0.5. The transverse momentum pT of charged particles is measured down to 0.15 GeV/c which gives access to the low pT fragments of the jet. Jets found in heavy-ion collisions are corrected event-by-event for average background density and on an inclusive basis (via unfolding) for residual background fluctuations and detector effects. A strong suppression of jet production in central events with respect to peripheral events is observed. The suppression is found to be similar to the suppression of charged hadrons, which suggests that substantial energy is radiated at angles larger than the jet resolution parameter R=0.3 considered in the analysis. The fragmentation bias introduced by selecting jets with a high pT leading particle, which rejects jets with a soft fragmentation pattern, has a similar effect on the jet yield for central and peripheral events. The ratio of jet spectra with R=0.2 and R=0.3 is found to be similar in Pb-Pb and simulated PYTHIA pp events, indicating no strong broadening of the radial jet structure in the reconstructed jets with R<0.3.
Global-scale assessments of freshwater fluxes and storages by hydrological models under historic climate conditions are subject to a variety of uncertainties. Using the global hydrological model WaterGAP 2.2, we investigated the sensitivity of simulated freshwater fluxes and water storage variations to five major sources of uncertainty: climate forcing, land cover input, model structure, consideration of human water use and calibration (or no calibration). In a modelling experiment, five variants of the standard version of WaterGAP 2.2 were generated that differed from the standard version only regarding the investigated source of uncertainty. Sensitivity was analyzed by comparing water fluxes and water storage variations computed by the variants to those of the standard version, considering both global averages and grid cell values for the time period 1971–2000. The basin-specific calibration approach for WaterGAP, which forces simulated mean annual river discharge to be equal to observed values at 1319 gauging stations (representing 54% of global land area except Antarctica and Greenland), has the highest effect on modelled water fluxes and leads to the best fit of modelled to observed monthly and seasonal river discharge. Alternative state-of-the-art climate forcings rank second regarding the impact on grid cell specific fluxes and water storage variations, and their impact is ubiquitous and stronger than that of alternative land cover inputs. The diverse model refinements during the last decade lead to an improved fit to observed discharge, and affect globally averaged fluxes and storage values (the latter mainly due to modelling of groundwater depletion) but only affect a relatively small number of grid cells. Considering human water use is important for the global water storage trend (in particular in the groundwater compartment) but impacts on water fluxes are rather local and only important where water use is high. The best fit to observed time series of monthly river discharge (Nash–Sutcliffe criterion) or discharge seasonality is obtained with the standard WaterGAP 2.2 model version which is calibrated and driven by a sequence of two time series of daily observation-based climate forcings, WFD/WFDEI. Discharge computed by a calibrated model version using monthly CRU 3.2 and GPCC v6 climate input reduced the fit to observed discharge for most stations. Taking into account the investigated uncertainties of climate and land cover data, we estimate that the global 1971–2000 discharge into oceans and inland sinks is between 40 000 and 42 000 km3 yr−1. The range is mainly due differences in precipitation data that affect discharge in uncalibrated river basins. Actual evapotranspiration, with approximately 70 000 km3 yr−1, is rather unaffected by climate and land cover in global sum but differs spatially. Human water use is calculated to reduce river discharge by approximately 1000 km3 yr−1. Thus, global renewable water resources are estimated to range between 41 000 and 43 000 km3 yr−1. The climate data sets WFD (available until 2001) and WFDEI (starting in 1979) were found to be inconsistent with respect to short wave radiation data, resulting in strongly different potential evapotranspiration. Global assessments of freshwater fluxes and storages would therefore benefit from the development of a global data set of consistent daily climate forcing from 1900 to current.
Considerations of the alimentary canal, mesodermal reproductive organs, and ventral nervous system and brain are provided. The treatise is based on studies of 301 species, representing 99 genera, 11 subfamilies, and two cleroid families. A comparative morphology summary is provided. Morphological variations of the stomodaeum, ventriculus, malpighian tubules, confi guration of the spermathecal capsule, shape of the bursa copulatrix, male accessory glands, and testes provide taxonomically useful characteristics. Provided are 252 illustrations. A new name, Katachaetosoma, nom. nov., is proposed to replace the preoccupied name Chaetosoma Dejean (Insecta: Coleoptera: Cerambycidae).
(Micro)plastics in the aquatic environment are an issue of emerging concern. However, to date, there is considerable lack of knowledge on the abundance and toxicity of plastic debris in aquatic ecosystems, especially with regard to the freshwater situation. In this editorial, we briefly discuss important aspects of the research on environmental (micro)plastics to stimulate research and call for papers.
Focus on quantum efficiency
(2014)
Technologies which convert light into energy, and vice versa, rely on complex, microscopic transport processes in the condensed phase, which obey the laws of quantum mechanics, but hitherto lack systematic analysis and modeling. Given our much improved understanding of multicomponent, disordered, highly structured, open quantum systems, this ‘focus on’ collection collects cuttingedge research on theoretical and experimental aspects of quantum transport in truly complex systems as defined, e.g., by the macromolecular functional complexes at the heart of photosynthesis, by organic quantum wires, or even photovoltaic devices. To what extent microscopic quantum coherence effects can (be made to) impact on macroscopic transport behavior is an equally challenging and controversial question, and this "focus on" collection provides a setting for the present state of affairs, as well as for the "quantum opportunities" on the horizon.
Background: A discontinuous dose response relationship is a major characteristic of the anti-inflammatory effects of low-dose X-irradiation therapy. Although recent data indicate an involvement of a variety of molecular mechanisms in these characteristics, the impact of reactive oxygen species (ROS) production to give rise or contribute to these phenomena in endothelial cells (EC) remains elusive.
Material and methods: HUVEC derived immortalized EA.hy926 cells were stimulated by tumor necrosis factor-α (TNF-α, 20 ng/ml) 4 h before irradiation with doses ranging from 0.3 to 1 Gy. To analyse DNA repair capacity, phospho-histone H2AX foci were assayed at 1 h, 4 h and 24 h after irradiation. ROS production and superoxide dismutase (SOD) activity were analysed by fluorometric 2',7'-dichlorodihydrofluorescein-diacetate (H2DCFDA) and colorimetric assays. A functional impact of ROS on γH2AX production was analysed by treatment with the scavenger N-acetyl-L-cysteine (NAC).
Results: Irrespective of stimulation by TNF-α, EA.hy926 cells revealed a linear dose response characteristic of γH2AX foci detection at 1 h and 4 h after irradiation. By contrast, we observed a discontinuity in residual γH2AX foci detection at 24 h after irradiation with locally elevated values following a 0.5 Gy exposure that was abolished by inhibition of ROS by NAC. Moreover, SOD protein expression was significantly decreased at doses of 0.5 Gy and 0.7 Gy concomitant with a reduced SOD activity.
Conclusion: These data implicate a non-linear regulation of ROS production and SOD activity in EA.hy926 EC following irradiation with doses < 1 Gy that may contribute to a discontinuous dose-response relationship of residual γH2AX foci detection.
Association of autoimmune Addison's disease with alleles of STAT4 and GATA3 in European cohorts
(2014)
Background: Gene variants known to contribute to Autoimmune Addison's disease (AAD) susceptibility include those at the MHC, MICA, CIITA, CTLA4, PTPN22, CYP27B1, NLRP-1 and CD274 loci. The majority of the genetic component to disease susceptibility has yet to be accounted for.
Aim: To investigate the role of 19 candidate genes in AAD susceptibility in six European case-control cohorts.
Methods: A sequential association study design was employed with genotyping using Sequenom iPlex technology. In phase one, 85 SNPs in 19 genes were genotyped in UK and Norwegian AAD cohorts (691 AAD, 715 controls). In phase two, 21 SNPs in 11 genes were genotyped in German, Swedish, Italian and Polish cohorts (1264 AAD, 1221 controls). In phase three, to explore association of GATA3 polymorphisms with AAD and to determine if this association extended to other autoimmune conditions, 15 SNPs in GATA3 were studied in UK and Norwegian AAD cohorts, 1195 type 1 diabetes patients from Norway, 650 rheumatoid arthritis patients from New Zealand and in 283 UK Graves' disease patients. Meta-analysis was used to compare genotype frequencies between the participating centres, allowing for heterogeneity.
Results: We report significant association with alleles of two STAT4 markers in AAD cohorts (rs4274624: P = 0.00016; rs10931481: P = 0.0007). In addition, nominal association of AAD with alleles at GATA3 was found in 3 patient cohorts and supported by meta-analysis. Association of AAD with CYP27B1 alleles was also confirmed, which replicates previous published data. Finally, nominal association was found at SNPs in both the NF-κB1 and IL23A genes in the UK and Italian cohorts respectively.
Conclusions: Variants in the STAT4 gene, previously associated with other autoimmune conditions, confer susceptibility to AAD. Additionally, we report association of GATA3 variants with AAD: this adds to the recent report of association of GATA3 variants with rheumatoid arthritis.
In the past sixty years, excessive water consumption and dam construction have significantly influenced natural flow regimes and surface freshwater ecosystems throughout China, and thus resulted in serious environmental problems. In order to balance the competing water demands between human and environment and provide knowledge on sustainable water management, assessments on anthropogenic flow alterations and their impacts on aquatic and riparian ecosystems in China are needed.
In this study, the first evaluation on quantitative relationships between anthropogenic flow alterations and ecological responses in eleven river basins and watersheds in China was performed based on the data that could be obtained from published case studies. Quantitative relationships between changes in average annual discharge, seasonal low flow and seasonal high flow and changes in ecological indicators (fish diversity, fish catch and vegetation cover, etc.) were analyzed. The results showed that changes in riparian vegetation cover as well as changes in fish diversity and fish catch were strongly correlated with the changes in flow magnitude (r = 0.77, 0.66), especially with changes in average annual river discharge. In addition, more than half of the variations in vegetation cover could be explained by changes in average annual river discharge (r² = 0.63) and roughly 50 % changes in fish catch in arid and semi-arid region and 60% changes of fish catch in humid region could be related to alterations in average annual river discharge (r² = 0.53, 0.58).
In a supplementary analysis of this study, the first estimation on quantitative relationships between decreases in native fish species richness and anthropogenic flow alterations in 34 river basins and sub-basins in China was conducted. Linear relationships between losses of native fish species and five ecologically relevant flow indicators were analyzed by single and multiple regression models. For the single regression analysis, significant linear relationships were detected for the indicators of long-term average annual discharge (ILTA) and statistical low flow Q90 (IQ90). For the multiple regressions, no indicator other than ILTA has significant relationships with changes in number of fish species mainly due to collinearity. Two conclusions emerged from the analysis: 1) losses of fish species were positively correlated with changes in ILTA in China and 2) indicator of ILTA was dominant over other flow indicators included in this research for the given dataset. These results provide a guideline for the sustainable water resources management in rivers with high risk of fish extinction in China.
Irrigation intensifies land use by increasing crop yield but also impacts water resources. It affects water and energy balances and consequently the microclimate in irrigated regions. Therefore, knowledge of the extent of irrigated land is important for hydrological and crop modelling, global change research, and assessments of resource use and management. Information on the historical evolution of irrigated lands is limited. The new global Historical Irrigation Dataset (HID) provides estimates of the temporal development of the area equipped for irrigation (AEI) between 1900 and 2005 at 5 arc-minute resolution. We collected subnational irrigation statistics from various sources and found that the global extent of AEI increased from 63 million ha (Mha) in 1900 to 112 Mha in 1950 and 306 Mha in 2005. We developed eight gridded versions of time series of AEI by combining subnational irrigation statistics with different data sets on the historical extent of cropland and pasture. Different rules were applied to maximize consistency of the gridded products to subnational irrigation statistics or to historical cropland and pasture data sets. The HID reflects very well the spatial patterns of irrigated land in the western United States as shown on historical maps. Mean aridity on irrigated land increased and river discharge decreased from 1900–1950 whereas aridity decreased from 1950–2005. The dataset and its documentation are made available in an open data repository at https://mygeohub.org/publications/8 (doi:10.13019/M2MW2G).
Water footprints have been proposed as sustainability indicators, relating the consumption of goods like food to the amount of water necessary for their production and the impacts of that water use in the source regions. We further developed the existing water footprint methodology, by globally resolving virtual water flows from production to consumption regions for major food crops at 5 arcmin spatial resolution. We distinguished domestic and international flows, and assessed local impacts of export production. Applying this method to three exemplary cities, Berlin, Delhi and Lagos, we find major differences in amounts, composition, and origin of green and blue virtual water imports, due to differences in diets, trade integration and crop water productivities in the source regions. While almost all of Delhi's and Lagos' virtual water imports are of domestic origin, Berlin on average imports from more than 4000 km distance, in particular soy (livestock feed), coffee and cocoa. While 42% of Delhi's virtual water imports are blue water based, the fractions for Berlin and Lagos are 2 and 0.5%, respectively, roughly equal to the water volumes abstracted in these two cities for domestic water use. Some of the external source regions of Berlin's virtual water imports appear to be critically water scarce and/or food insecure. However, for deriving recommendations on sustainable consumption and trade, further analysis of context-specific costs and benefits associated with export production will be required.
Two new species and a new genus of Cerambycidae are described from South America: Cotyclytus arriagadai sp. nov., from Bolivia; and Lembu dieguezi, gen. nov., sp. nov., from Paraguay. Orthomegas irroratus (Lameere, 1915) is redescribed, based on the second and third known specimens, and its distribution is expanded to include Ecuador. The male of Jamesia fuscofasciata Dillon and Dillon, 1952 is described and illustrated for the fi rst time, and the distribution of the species is expanded to Peru. Thirty-two new country records (twelve for Paraguay, fi fteen for Peru, two for Ecuador, three for Bolivia) and one new province record (Argentina) are presented.
Five new species of Cerambycidae (Coleoptera) from Peru and Bolivia, and two new records for Peru
(2014)
The following four new species of Cerambycidae are described from Bolivia: Chrysoprasis imitatrix (Heteropsini); Carneades vigneaulti (Colobotheini); Colobothea larriveei (Colobotheini); Colobothea boliviana (Colobotheini). Esthlogena (Pseudotaxia) bella (Pteropliini) is described from Peru. A key to species of Carneades Bates, 1869 is provided. The other new species are included in previously published keys. Additionally, two new country records are reported for the fauna of Peru.
Imitation paradigms are used in various domains of developmental psychological research to assess various cognitive processes such as memory (deferred imitation), action perception and action understanding (mainly direct imitation), as well as categorization and learning about objects (deferred imitation with a change in target objects and generalized imitation). Although these processes are most likely not independent from each other, their relations are still largely unclear. On the one hand, deferred imitation studies have shown that infants' performance improves with increasing age, resulting in the reproduction of more target actions after longer delay intervals. On the other hand, imitation studies focusing on infants' action understanding have found that infants do not necessarily imitate the model's exact actions – actions or action steps that seem to be irrational or irrelevant are omitted by infants under certain circumstances (selective imitation). Additionally, findings of imitation studies that require a transfer of the target actions to novel objects have demonstrated that infants do not only learn about actions, but also about objects, when they engage in imitation.
The present dissertation aims at integrating different perspectives of imitation research by testing 12- and 18-month-old infants in deferred imitation tests consisting of functional vs. arbitrary target actions, and by combining deferred imitation with eye tracking in half of the experiments. A deferred imitation paradigm was chosen to assess memory performance. Systematic variation of target action characteristics enabled the assessment of infants' imitation pattern, i.e., if they would imitate one kind of target actions more frequently than the other. Functionality was chosen as the action characteristic in focus because function is an object's most important property, thus this variation might shed some light on infants' learning about objects in the context of an imitation test. The main goal of the eye tracking experiments was to tackle the relations between infants' visual attention to, and deferred imitation of, different kinds of target actions.
The behavioral experiments revealed that both 12- and 18-month-olds imitated significantly more functional than arbitrary target actions after a delay of 30 minutes. In addition, while 12-month-olds showed a memory effect only for functional actions, 18-month-olds showed a memory effect for both kinds of actions. Thus, 12-month-olds imitated strictly selectively, and 18-month-olds imitated more exactly. This shows that the well established memory effect is modulated by target action functionality, which affects 12- and 18-month-olds' imitation differently. Furthermore, when retested after a two weeks delay, 18-month-olds' performance rates of functional and arbitrary target actions decreased parallel. This suggests that selective imitation is not affected by the duration of the retention interval, and that selection of target actions takes place at an earlier stage of action perception and memory processes.
In the eye tracking experiments, both 12- and 18-month-olds' imitation patterns replicated the findings of the behavioral experiments, showing consistently higher imitation rates of functional than arbitrary target actions. Contrary to this, infants' fixation times to the target actions were not affected by target action functionality. This contrast was supported by statistical analyses that found no clear correspondence between visual attention to and deferred imitation of target actions. This suggests that selective imitation cannot be explained by selective visual attention. Nevertheless, finer-grained analyses of gaze and imitation data in the 18 months old group suggested that infants' increased attention to the social-communicative context of the imitation task was related to more exact imitation, i.e. imitation of not only functional, but also arbitrary target actions.
The findings are discussed against the background of imitation theories, with regard to the relations between different cognitive processes underlying infants' imitation, such as memory, action perception and learning about objects.
Recognizing individual faces is an important human ability that highly depends on experience. This is reflected in the so called other-race effect; adults are better at recognizing faces from their own ethnic group, while very young infants do not show this specialization yet. Two experiments examined whether 3-year-old children from two different cultural backgrounds show the other-race effect. In Experiment 1, German children (N = 41) were presented with a forced choice paradigm where they were asked to recognize female Caucasian or African faces. In Experiment 2, 3-year-olds from Cameroon (N = 66) participated in a similar task using the same stimulus material. In both cultures the other-race effect was present; children were better at recognizing individual faces from their own ethnic group. In addition, German children performed at a higher overall level of accuracy than Cameroonians. The results are discussed in relation to cultural aspects in particular.
Expressivist theories of punishment, according to which a penal sanction articulates or expresses a certain meaning to the offender, to the victim and to society, become more and more prominent among the traditional theories of punishment as retribution or deterrence. What these theories have in common is the idea that the conveyance of the meaning is in need of a communicative action, and that the penal sanction is such a communicative act. This article argues that pure communicative theories of punishment face great difficulties in generating any justification for hard treatment. One challenge is that certain types of sanctions – in particularly, hard treatment – restrict the communicative opportunities of the incarcerated individual; which generates a paradox, in that it turns punishment into a communicative action of non-communication. Beyond that, moreover, all practices of hard treatment potentially become unnecessary, if expressing the moral message of censure constitutes a kind of action in itself, and as such, itself a treatment of the offender, embedded in a communicative relationship between offender, victim and society; such that we may be able to think of the history of punishment as a development where hard treatment becomes more and more unnecessary for the conveyance of the message.
IKKα promotes intestinal tumorigenesis by limiting recruitment of M1-like polarized myeloid cells
(2014)
The recruitment of immune cells into solid tumors is an essential prerequisite of tumor development. Depending on the prevailing polarization profile of these infiltrating leucocytes, tumorigenesis is either promoted or blocked. Here, we identify IκB kinase α (IKKα) as a central regulator of a tumoricidal microenvironment during intestinal carcinogenesis. Mice deficient in IKKα kinase activity are largely protected from intestinal tumor development that is dependent on the enhanced recruitment of interferon γ (IFNγ)-expressing M1-like myeloid cells. In IKKα mutant mice, M1-like polarization is not controlled in a cell-autonomous manner but, rather, depends on the interplay of both IKKα mutant tumor epithelia and immune cells. Because therapies aiming at the tumor microenvironment rather than directly at the mutated cancer cell may circumvent resistance development, we suggest IKKα as a promising target for colorectal cancer (CRC) therapy.
Tumor cell plasticity is an event that has been observed in several malignancies. In fact, most of the solid tumors are characterized by cellular heterogeneity and undergo constant changes as the tumor develops. The increased plasticity displayed by these cells allows them to acquire additional properties, enabling epithelial-mesenchymal transitions, dedifferentiation and the acquisition of stem cell-like properties. Here we discuss the particular importance of an inflammatory microenvironment for the bidirectional control of cellular plasticity and the potential for therapeutic intervention.
Background: The current taxonomy of the African giraffe (Giraffa camelopardalis) is primarily based on pelage pattern and geographic distribution, and nine subspecies are currently recognized. Although genetic studies have been conducted, their resolution is low, mainly due to limited sampling. Detailed knowledge about the genetic variation and phylogeography of the South African giraffe (G. c. giraffa) and the Angolan giraffe (G. c. angolensis) is lacking. We investigate genetic variation among giraffe matrilines by increased sampling, with a focus on giraffe key areas in southern Africa.
Results: The 1,562 nucleotides long mitochondrial DNA dataset (cytochrome b and partial control region) comprises 138 parsimony informative sites among 161 giraffe individuals from eight populations. We additionally included two okapis as an outgroup. The analyses of the maternally inherited sequences reveal a deep divergence between northern and southern giraffe populations in Africa, and a general pattern of distinct matrilineal clades corresponding to their geographic distribution. Divergence time estimates among giraffe populations place the deepest splits at several hundred thousand years ago.
Conclusions: Our increased sampling in southern Africa suggests that the distribution ranges of the Angolan and South African giraffe need to be redefined. Knowledge about the phylogeography and genetic variation of these two maternal lineages is crucial for the development of appropriate management strategies.
Ursine bears are a mammalian subfamily that comprises six morphologically and ecologically distinct extant species. Previous phylogenetic analyses of concatenated nuclear genes could not resolve all relationships among bears, and appeared to conflict with the mitochondrial phylogeny. Evolutionary processes such as incomplete lineage sorting and introgression can cause gene tree discordance and complicate phylogenetic inferences, but are not accounted for in phylogenetic analyses of concatenated data. We generated a high-resolution data set of autosomal introns from several individuals per species and of Y-chromosomal markers. Incorporating intraspecific variability in coalescence-based phylogenetic and gene flow estimation approaches, we traced the genealogical history of individual alleles. Considerable heterogeneity among nuclear loci and discordance between nuclear and mitochondrial phylogenies were found. A species tree with divergence time estimates indicated that ursine bears diversified within less than 2 My. Consistent with a complex branching order within a clade of Asian bear species, we identified unidirectional gene flow from Asian black into sloth bears. Moreover, gene flow detected from brown into American black bears can explain the conflicting placement of the American black bear in mitochondrial and nuclear phylogenies. These results highlight that both incomplete lineage sorting and introgression are prominent evolutionary forces even on time scales up to several million years. Complex evolutionary patterns are not adequately captured by strictly bifurcating models, and can only be fully understood when analyzing multiple independently inherited loci in a coalescence framework. Phylogenetic incongruence among gene trees hence needs to be recognized as a biologically meaningful signal.
The taxon Syndermata comprises the biologically interesting wheel animals (“Rotifera”: Bdelloidea + Monogononta + Seisonidea) and thorny-headed worms (Acanthocephala), and is central for testing superordinate phylogenetic hypotheses (Platyzoa, Gnathifera) in the metazoan tree of life. Recent analyses of syndermatan phylogeny suggested paraphyly of Eurotatoria (free-living bdelloids and monogononts) with respect to endoparasitic acanthocephalans. Data of epizoic seisonids, however, were absent, which may have affected the branching order within the syndermatan clade. Moreover, the position of Seisonidea within Syndermata should help in understanding the evolution of acanthocephalan endoparasitism. Here, we report the first phylogenomic analysis that includes all four higher-ranked groups of Syndermata. The analyzed data sets comprise new transcriptome data for Seison spec. (Seisonidea), Brachionus manjavacas (Monogononta), Adineta vaga (Bdelloidea), and Paratenuisentis ambiguus (Acanthocephala). Maximum likelihood and Bayesian trees for a total of 19 metazoan species were reconstructed from up to 410 functionally diverse proteins. The results unanimously place Monogononta basally within Syndermata, and Bdelloidea appear as the sister group to a clade comprising epizoic Seisonidea and endoparasitic Acanthocephala. Our results support monophyly of Syndermata, Hemirotifera (Bdelloidea + Seisonidea + Acanthocephala), and Pararotatoria (Seisonidea + Acanthocephala), rejecting monophyly of traditional Rotifera and Eurotatoria. This serves as an indication that early acanthocephalans lived epizoically or as ectoparasites on arthropods, before their complex lifecycle with arthropod intermediate and vertebrate definite hosts evolved.
BACKGROUND: Micro-RNAs (miRNA) are attributed to the systems biological role of a regulatory mechanism of the expression of protein coding genes. Research has identified miRNAs dysregulations in several but distinct pathophysiological processes, which hints at distinct systems-biology functions of miRNAs. The present analysis approached the role of miRNAs from a genomics perspective and assessed the biological roles of 2954 genes and 788 human miRNAs, which can be considered to interact, based on empirical evidence and computational predictions of miRNA versus gene interactions.
RESULTS: From a genomics perspective, the biological processes in which the genes that are influenced by miRNAs are involved comprise of six major topics comprising biological regulation, cellular metabolism, information processing, development, gene expression and tissue homeostasis. The usage of this knowledge as a guidance for further research is sketched for two genetically defined functional areas: cell death and gene expression. Results suggest that the latter points to a fundamental role of miRNAs consisting of hyper-regulation of gene expression, i.e., the control of the expression of such genes which control specifically the expression of genes.
CONCLUSIONS: Laboratory research identified contributions of miRNA regulation to several distinct biological processes. The present analysis transferred this knowledge to a systems-biology level. A comprehensible and precise description of the biological processes in which the genes that are influenced by miRNAs are notably involved could be made. This knowledge can be employed to guide future research concerning the biological role of miRNA (dys-) regulations. The analysis also suggests that miRNAs especially control the expression of genes that control the expression of genes.
Computational analyses of functions of gene sets obtained in microarray analyses or by topical database searches are increasingly important in biology. To understand their functions, the sets are usually mapped to Gene Ontology knowledge bases by means of over-representation analysis (ORA). Its result represents the specific knowledge of the functionality of the gene set. However, the specific ontology typically consists of many terms and relationships, hindering the understanding of the ‘main story’. We developed a methodology to identify a comprehensibly small number of GO terms as “headlines” of the specific ontology allowing to understand all central aspects of the roles of the involved genes. The Functional Abstraction method finds a set of headlines that is specific enough to cover all details of a specific ontology and is abstract enough for human comprehension. This method exceeds the classical approaches at ORA abstraction and by focusing on information rather than decorrelation of GO terms, it directly targets human comprehension. Functional abstraction provides, with a maximum of certainty, information value, coverage and conciseness, a representation of the biological functions in a gene set plays a role. This is the necessary means to interpret complex Gene Ontology results thus strengthening the role of functional genomics in biomarker and drug discovery.
Data structures and advanced models of computation on big data : report from Dagstuhl seminar 14091
(2014)
This report documents the program and the outcomes of Dagstuhl Seminar 14091 "Data Structures and Advanced Models of Computation on Big Data". In today's computing environment vast amounts of data are processed, exchanged and analyzed. The manner in which information is stored profoundly influences the efficiency of these operations over the data. In spite of the maturity of the field many data structuring problems are still open, while new ones arise due to technological advances.
The seminar covered both recent advances in the "classical" data structuring topics as well as new models of computation adapted to modern architectures, scientific studies that reveal the need for such models, applications where large data sets play a central role, modern computing platforms for very large data, and new data structures for large data in modern architectures.
The extended abstracts included in this report contain both recent state of the art advances and lay the foundation for new directions within data structures research.
This essay reviews a cornerstone of the European Banking Union project, the resolution of systemically important banks. The focus is on the inherent conflict between a possible intervention by resolution authorities, conditional on a crisis situation, and effective prevention prior to a crisis. Moreover, the paper discusses the rules for bail-in debt and conversion rules for different layers of debt. Finally, some organizational requirements to achieve effective resolution results will be analyzed.
On November 8, 2013, several members of the British House of Lords’ Subcommittee A conducted a hearing at the ECB in Frankfurt, Germany, on “Genuine Economic and Monetary Union and its Implications for the UK”. Professors Otmar Issing and Jan Pieter Krahnen were called as expert witnesses.
The testimony began with a general discussion on the elements considered necessary for a functioning internal market. Do economic union and monetary union require a fiscal union or even a political union, beyond the elements of the banking union currently being prepared? In this context, also the critique of the German current account surplus and the international expectations that Germany stimulate internal demand to support growth in crisis countries, were discussed.
With regard to the monetary union, the members of the subcommittee asked for an assessment of how European nations and the banking industry would have fared in the banking crisis that followed the Lehman collapse, had there not been a common currency. Given the important role that the ECB has played in the course of the crisis management, the members further asked for an evaluation of the OMT-program of the ECB and also if the monetary union is in need of common debt instruments, in order to provide the ECB with the possibility of buying EU liabilities, comparable to the Fed buying US Treasury bonds. Finally, the dual role of the ECB for monetary policy and banking supervision was an issue touched on by several questions.
We demonstrate high-density labelling of cellular DNA and RNA using click chemistry and perform confocal and super-resolution microscopy. We visualize the crescent and ring-like structure of densely packed RNA in nucleoli. We further demonstrate click chemistry with unnatural amino acids for super-resolution imaging of outer-membrane proteins of E. coli.
RNA modifications are present in all three kingdoms of life and detected in all classes of cellular RNAs. RNA modifications are diverse, with more than 100 types of chemical modifications identified to date. These chemical modifications expand the topological repertoire of RNAs and are expected to fine-tune their functions. Ribosomal RNA (rRNA) contains two types of covalent modifications, either methylation on the sugar (Nm) or bases (mN), or base isomerization (conversion of uridine into pseudouridines, "). Pseudouridylations and ribose methylations are catalyzed by site-specific H/ACA and C/D box snoRNPs, respectively. The RNA component (snoRNA) of both types of snoRNPs is responsible for the site selection by base pairing with the rRNA substrate, whereas the protein component catalyzes the modification reaction: Nop1 in C/D box and Cbf5 in H/ACA box snoRNPs. Contrastingly, base methylations are performed by snoRNA independent, ‘protein-only’, methyltransferases (MTases). rRNA modifications occur at highly conserved positions, all clustering around functional ribosomal sites. Mutations in factors involved in rRNA modification have been linked to severe human diseases (e.g. X-linked Dyskeratosis congenita). Emerging evidences indicate that heterogeneity in RNA modification prevails, i.e. not all positions are modified at all time, and the concept of ‘specialized ribosomes’ has been coined. rRNA modification heterogeneity has been correlated with disease etiology (cancer), and shown to play a role in cell differentiation(hematopoiesis). Remarkably, alteration in rRNA modification patterns profoundly affects the preference of ribosomes for cap- versus IRESdependent translation initiation, with major consequences on cell physiology.
Bei ca. 95% der chronisch myeloischen Leukämie (CML) und 20-30% der akuten lymphatischen Leukämie (ALL) des Erwachsenen liegt eine reziproke Chromosomentranslokation t(9;22)(q34;q11) vor, in deren Rahmen das BCR (Breakpoint Cluster Region) Gen auf Chromosom 22 mit dem ABL (Abelson-Leukämie-Virus) Gen auf Chromosom 9 fusioniert. Auf Chromosom 22 gibt es zwei verschiedene Bruchpunkte, die somit zur Bildung von unterschiedlichen Fusionsgenen führen. Bei der CML findet man den sogenannten „großen“ Bruchpunkt (M-bcr), während bei der Ph+ ALL der sogenannte „kleine“ Bruchpunkt (m-bcr) vorkommt. Das hybride Fusionsgen auf Chromosom 22q+ (Philadelphia-Chromosom) kodiert für das jeweilige BCR/ABL Protein, während das Fusionsgen auf Chromosom 9q+ für das reziproke ABL/BCR Protein kodiert. Das ABL-Protein ist eine Nicht-Rezeptor Tyrosinkinase, die eine wichtige Rolle in der Signaltransduktion und der Regulation des Zellwachstums spielt. Im BCR/ABL Fusionsprotein wird die Kinase-Aktivität von ABL, die im Normalfall streng reguliert ist, durch die Fusion mit BCR konstitutiv aktiv. Dadurch kommt es zur Deregulierung intrazellulärer Signalwege, welche die maligne Transformation hämatopoetischer Zellen verursacht. Eine zielgerichtete Inhibierung von BCR/ABL mittels ABL-Kinase-Inhibitoren induziert Apoptose in BCR/ABL transformierten Zellen, was eine komplette Remission im größten Teil Ph+ Leukämie Patienten zur Folge hat.
The transcription factor Tal1 is a critical activator or repressor of gene expression in hematopoiesis and leukaemia. The mechanism by which Tal1 differentially influences transcription of distinct genes is not fully understood. Here we show that Tal1 interacts with the peptidylarginine deiminase IV (PADI4). We demonstrate that PADI4 can act as an epigenetic coactivator through influencing H3R2me2a. At the Tal1/PADI4 target gene IL6ST the repressive H3R2me2a mark triggered by PRMT6 is counteracted by PADI4, which augments the active H3K4me3 mark and thus increases IL6ST expression. In contrast, at the CTCF promoter PADI4 acts as a repressor. We propose that the influence of PADI4 on IL6ST transcription plays a role in the control of IL6ST expression during lineage differentiation of hematopoietic stem/progenitor cells. These results open the possibility to pharmacologically influence Tal1 in leukaemia.
Translation fidelity and efficiency require multiple ribosomal (r)RNA modifications that are mostly mediated by small nucleolar (sno)RNPs during ribosome production. Overlapping basepairing of snoRNAs with pre-rRNAs often necessitates sequential and efficient association and dissociation of the snoRNPs, however, how such hierarchy is established has remained unknown so far. Here, we identify several late-acting snoRNAs that bind pre-40S particles in human cells and show that their association and function in pre-40S complexes is regulated by the RNA helicase DDX21. We map DDX21 crosslinking sites on pre-rRNAs and show their overlap with the basepairing sites of the affected snoRNAs. While DDX21 activity is required for recruitment of the late-acting snoRNAs SNORD56 and SNORD68, earlier snoRNAs are not affected by DDX21 depletion. Together, these observations provide an understanding of the timing and ordered hierarchy of snoRNP action in pre-40S maturation and reveal a novel mode of regulation of snoRNP function by an RNA helicase in human cells.
The administration of intravenous fluid to critically ill patients is one of the most common but also one of the most fiercely debated interventions in intensive care medicine. During the past decade, a number of important studies have been published which provide clinicians with improved knowledge regarding the timing, the type and the amount of fluid they should give to their critically ill patients. However, despite the fact that many thousands of patients have been enrolled in these trials of alternative fluid strategies, consensus remains elusive and practice is widely variable. Early adequate resuscitation of patients in shock followed by a restrictive strategy may be associated with better outcomes. Colloids such as modern hydroxyethyl starch are more effective than crystalloids in early resuscitation of patients in shock, and are safe when administered during surgery. However, these colloids may not be beneficial later in the course of intensive care treatment and should best be avoided in intensive care patients who have a high risk of developing acute kidney injury. Albumin has no clear benefit over saline and is associated with increased mortality in neurotrauma patients. Balanced fluids reduce the risk of hyperchloraemic acidosis and possibly kidney injury. The use of hypertonic fluids in patients with sepsis and acute lung injury warrants further investigation and should be considered experimental at this stage. Fluid therapy impacts relevant patient-related outcomes. Clinicians should adopt an individualized strategy based on the clinical scenario and best available evidence. One size does not fit all.