Refine
Year of publication
- 2014 (1214) (remove)
Document Type
- Article (588)
- Part of Periodical (163)
- Working Paper (149)
- Book (134)
- Doctoral Thesis (86)
- Report (27)
- Part of a Book (23)
- Conference Proceeding (18)
- Review (10)
- Preprint (8)
Language
- English (1214) (remove)
Keywords
- taxonomy (21)
- new species (19)
- Syntax (11)
- Inversionsfigur (10)
- Multistability (10)
- Multistable figures (10)
- Wahrnehmungswechsel (10)
- morphology (8)
- Bantusprachen (7)
- Benjamin, Walter (7)
Institute
- Medizin (231)
- Wirtschaftswissenschaften (149)
- Center for Financial Studies (CFS) (131)
- Physik (101)
- Biowissenschaften (88)
- Sustainable Architecture for Finance in Europe (SAFE) (86)
- House of Finance (HoF) (82)
- Biochemie und Chemie (48)
- Geowissenschaften (41)
- Gesellschaftswissenschaften (33)
ND3, ND1 and 39kDa subunits are more exposed in the de-active form of bovine mitochondrial complex I
(2014)
An intriguing feature of mitochondrial complex I from several species is the so-called A/D transition, whereby the idle enzyme spontaneously converts from the active (A) form to the de-active (D) form. The A/D transition plays an important role in tissue response to the lack of oxygen and hypoxic deactivation of the enzyme is one of the key regulatory events that occur in mitochondria during ischaemia. We demonstrate for the first time that the A/D conformational change of complex I does not affect the macromolecular organisation of supercomplexes in vitro as revealed by two types of native electrophoresis. Cysteine 39 of the mitochondrially-encoded ND3 subunit is known to become exposed upon de-activation. Here we show that even if complex I is a constituent of the I+III2+IV (S1) supercomplex, cysteine 39 is accessible for chemical modification in only the D-form. Using lysine-specific fluorescent labelling and a DIGE-like approach we further identified two new subunits involved in structural rearrangements during the A/D transition: ND1 (MT-ND1) and 39kDa (NDUFA9). These results clearly show that structural rearrangements during de-activation of complex I include several subunits located at the junction between hydrophilic and hydrophobic domains, in the region of the quinone binding site. De-activation of mitochondrial complex I results in concerted structural rearrangement of membrane subunits which leads to the disruption of the sealed quinone chamber required for catalytic turnover.
SAFE Professor Michalis Haliassos was a member of the National Council for Research and Technology (ESET) established by the Government of Greece for the period 2010-2013. The council, consisting of eleven scientists from a range of disciplines, has now published their communiqué "National Strategic Framework for Research and Innovation 2014 -2020".
To promote the advancement of research, technology and innovation in Greece, the strategic plan proposed by the authors seeks to identify areas of existing research strength and excellence that can be further advanced to become engines for progress and growth in Greece, as well as flaws inherent to the present system. The authors stress the need to address current constraints to growth, which include the declining education system; the confusion and weaknesses of R&D governance and management; the discontinuities and inefficiencies of resource allocation and investment; the lack of adaptation to clearly-defined national priorities; and the inadequate opportunities and funding for high-quality research and development to flourish. They stress the need for prioritisation and efficient allocation; stability of the policy frame; predictability of planning; provision of opportunity; recognition of excellence; and responsiveness to current and future needs.
Cytochrome P450 (CYP) epoxygenases generate bioactive lipid epoxides which can be further metabolized to supposedly less active diols by the soluble epoxide hydrolase (sEH). As the role of epoxides and diols in angiogenesis is unclear, we compared retinal vasculature development in wild-type and sEH−/− mice. Deletion of the sEH significantly delayed angiogenesis, tip cell, and filopodia formation, a phenomenon associated with activation of the Notch signaling pathway. In the retina, sEH was localized in Müller glia cells, and Müller cell–specific sEH deletion reproduced the sEH−/− retinal phenotype. Lipid profiling revealed that sEH deletion decreased retinal and Müller cell levels of 19,20–dihydroxydocosapentaenoic acid (DHDP), a diol of docosahexenoic acid (DHA). 19,20-DHDP suppressed endothelial Notch signaling in vitro via inhibition of the γ-secretase and the redistribution of presenilin 1 from lipid rafts. Moreover, 19,20-DHDP, but not the parent epoxide, was able to rescue the defective angiogenesis in sEH−/− mice as well as in animals lacking the Fbxw7 ubiquitin ligase, which demonstrate strong basal activity of the Notch signaling cascade. These studies demonstrate that retinal angiogenesis is regulated by a novel form of neuroretina–vascular interaction involving the sEH-dependent generation of a diol of DHA in Müller cells.
Myofacial Pain is the most common form of temporomandibular disorders (TMD), affecting principally women in reproductive age. The etiology of TMD is still controversial. Currently a multifactorial theory has received a great support among the scientific community. This theory draws attention to the interaction of psychological, neuromuscular and oral pathogenic factors. Objectives: to describe the possible etiological factors of the Myofacial Pain; and to evaluate the effectiveness of the current treatments for Myofacial Pain. Materials and methods: a narrative review of the etiological factors and epidemiological data of Myofacial Pain introduces this work. Thereafter the author presents five systematic reviews of RCTs which have been published during the last thirteen years (1999-2012) for the use of acupuncture, low level laser therapy, drugs, physiotherapeutical interventions, splint therapy, and psychosocial interventions in the treatment of Myofacial Pain. Moreover, the author reports a systematic review and meta-analysis of all the available literature of two modern approaches for the treatment of Myofacial Pain. A comparison between the “usual treatment” based on splint therapy and psychosocial interventions was conducted. Results: the author did not find sufficient evidence to support therapies based on one single intervention. However, the condition of the patients with myofacial pain could be treated more effectively with combined treatments. After comparing “usual treatment” with psychosocial interventions, the author observed a tendency of the latter to improve psychological outcomes, whereas the first one was slightly more effective to enhance clinical functional outcomes. In general, a high level of heterogeneity was observed among the included studies of the different systematic reviews. The quality of the studies is susceptible to be improved. Clinical implications: the author proposes core outcomes to be implemented within the research on myofacial pain in particular and temporomandibular disorders in general, in order to enable scientifical comparisons between different therapies.
Background: Hypoxia-inducible factor-1α (HIF-1α) and NF-κB play important roles in the inflammatory response after hemorrhagic shock and resuscitation (H/R). Here, the role of myeloid HIF-1α in liver hypoxia, injury, and inflammation after H/R with special regard to NF-κB activation was studied.
Methods: Mice with a conditional HIF-1α knockout (KO) in myeloid cell-line and wild-type (WT) controls were hemorrhaged for 90 min ( mm Hg) and resuscitated. Controls underwent only surgical procedures.
Results: After six hours, H/R enhanced the expression of HIF-1α-induced genes vascular endothelial growth factor (VEGF) and adrenomedullin (ADM). In KO mice, this was not observed. H/R-induced liver injury in HIF-1α KO was comparable to WT. Elevated plasma interleukin-6 (IL-6) levels after H/R were not reduced by HIF-1α KO. Local hepatic hypoxia was not significantly reduced in HIF-1α KO compared to controls after H/R. H/R-induced NF-κB phosphorylation in liver did not significantly differ between WT and KO.
Conclusions: Here, deleting HIF-1α in myeloid cells and thereby in Kupffer cells was not protective after H/R. This data indicates that other factors, such as NF-κB, due to its upregulated phosphorylation in WT and KO mice, contrary to HIF-1α, are rather key modulators of inflammation after H/R in our model.
Myelodysplastic syndromes (MDSs) represent clonal disorders mainly of the elderly that are characterized by ineffective hematopoiesis and an increased risk of transformation into acute myeloid leukemia. The pathogenesis of MDS is thought to evolve from accumulation and selection of specific genetic or epigenetic events. Emerging evidence indicates that MDS is not solely a hematopoietic disease but rather affects the entire bone marrow microenvironment, including bone metabolism. Many of these cells, in particular mesenchymal stem and progenitor cells (MSPCs) and osteoblasts, express a number of adhesion molecules and secreted factors that regulate blood regeneration throughout life by contributing to hematopoietic stem and progenitor cell (HSPC) maintenance, self-renewal and differentiation. Several endocrine factors, such as erythropoietin, parathyroid hormone and estrogens, as well as deranged iron metabolism modulate these processes. Thus, interactions between MSPC and HSPC contribute to the pathogenesis of MDS and associated pathologies. A detailed understanding of these mechanisms may help to define novel targets for diagnosis and possibly therapy. In this review, we will discuss the scientific rationale of "osteohematology" as an emerging research field in MDS and outline clinical implications.
Faith conversion experiences are first of all personal before being universal. While biblical history records relatively few conversion encounters as dramatic and as explosive as Saint Paul's on the road to Damascus, it is not rare for individuals in the throes of a religious conversion to fall prey to intensely agonizing confusion. That is what happened to Martin Jumbam when he marched for peace in his country alongside the charismatic and irrepressible Emeritus Archbishop of Douala in Cameroon, Christian Cardinal Tumi. He joined the prelate as a secular journalist but went back home more than ever conscious of his state as a fallen Christian, the first step in his journey of faith. Since then, all his writing, be it secular or religious, now bears the fruits of that encounter, characterized by intense empathy for the human person. This book recounts the myriad ways Jumbam's encounters with Christian Cardinal Tumi have activated, nourished and inspired his faith.
We study self- and cross-excitation of shocks in the Eurozone sovereign CDS market. We adopt a multivariate setting with credit default intensities driven by mutually exciting jump processes, to capture the salient features observed in the data, in particular, the clustering of high default probabilities both in time (over days) and in space (across countries). The feedback between jump events and the intensity of these jumps is the key element of the model. We derive closed-form formulae for CDS prices, and estimate the model by matching theoretical prices to their empirical counterparts. We find evidence of self-excitation and asymmetric cross-excitation. Using impulse-response analysis, we assess the impact of shocks and a potential policy intervention not just on a single country under scrutiny but also, through the effect on cross-excitation risk which generates systemic sovereign risk, on other interconnected countries.
Families are central to the social and emotional development of youth, and most families engage in musical activities together, such as listening to music or talking about their favorite songs. However, empirical evidence of the positive effects of musical family rituals on social cohesion and emotional well-being is scarce. Furthermore, the role of culture in the shaping of musical family rituals and their psychological benefits has been neglected entirely. This paper investigates musical rituals in families and in peer groups (as an important secondary socialization context) in two traditional/collectivistic and two secular/individualistic cultures, and across two developmental stages (adolescence vs. young adulthood). Based on cross-sectional data from 760 young people in Kenya, the Philippines, New Zealand, and Germany, our study revealed that across cultures music listening in families and in peer groups contributes to family and peer cohesion, respectively. Furthermore, the direct contribution of music in peer groups on well-being appears across cultural contexts, whereas musical family rituals affect emotional well-being in more traditional/collectivistic contexts. Developmental analyses show that musical family rituals are consistently and strongly related to family cohesion across developmental stages, whereas musical rituals in peer groups appear more dependent on the developmental stage (in interaction with culture). Contributing to developmental as well as cross-cultural psychology, this research elucidated musical rituals and their positive effects on the emotional and social development of young people across cultures. The implications for future research and family interventions are discussed.
In 1989 the triumphant discourse on the 'end of history' brought the death of socialism and the expansion of liberal democracy. The proclamation of the end of history could also be read literally, as the death of 'history' as a discipline with a homogenized narrative. It is in the same year that Pierra Nora wrote a groundbreaking article, which disentangled the fundamental opposition between history and memory, and at the end assumed the standpoint of memory. The article departs from the diagnosis of post-Yugoslav contemporary accounts of Yugoslav and partisan events. The critique of nationalist and Yugonostalgic discourses discloses shared assumptions that are based on the 'romantic' temporality of Nation and on history as a closed process. In the main part of the article the author works on the special, multiple temporality of partisan poetry that emerged during the WWII partisan struggle. The special temporality hinges on the productive and tensed relationship between the 'not yet existing' - the position of the new society free of foreign occupation, but also in a radically transformed society - and the contemporary struggle within war, which is also marked by the fear that the rupture of the struggle might not be remembered rightly, if at all. The memory of the present struggle remains to be the task to be realized not only for poets, but for everyone participating in the struggle. This is where the revolutionary temporality of the unfinished process comes to its fore, relating poetry to struggle, but again producing a form of poetry in the struggle.
A potential clinical and etiological overlap between schizophrenia (SZ) and bipolar disorder (BD) has long been a subject of discussion. Imaging studies imply functional and structural alterations of the hippocampus in both diseases. Thus, imaging this core memory region could provide insight into the pathophysiology of these disorders and the associated cognitive deficits. To examine possible shared alterations in the hippocampus, we conducted a multi-modal assessment, including functional and structural imaging as well as neurobehavioral measures of memory performance in BD and SZ patients compared with healthy controls. We assessed episodic memory performance, using tests of verbal and visual learning (HVLT, BVMT) in three groups of participants: BD patients (n = 21), SZ patients (n = 21) and matched (age, gender, education) healthy control subjects (n = 21). In addition, we examined hippocampal resting state functional connectivity, hippocampal volume using voxel-based morphometry (VBM) and fibre integrity of hippocampal connections using diffusion tensor imaging (DTI). We found memory deficits, changes in functional connectivity within the hippocampal network as well as volumetric reductions and altered white matter fibre integrity across patient groups in comparison with controls. However, SZ patients when directly compared with BD patients were more severely affected in several of the assessed parameters (verbal learning, left hippocampal volumes, mean diffusivity of bilateral cingulum and right uncinated fasciculus). The results of our study suggest a graded expression of verbal learning deficits accompanied by structural alterations within the hippocampus in BD patients and SZ patients, with SZ patients being more strongly affected. Our findings imply that these two disorders may share some common pathophysiological mechanisms. The results could thus help to further advance and integrate current pathophysiological models of SZ and BD.
The number of multilingual texts in the World Wide Web (WWW) is increasing dramatically and a multilingual economic zone like the European Union (EU) requires the availability of multilingual Natural Language Processing (NLP) tools. Due to a rapid development of NLP tools, many lexical, syntactic, semantic and other linguistic features have been used in different NLP applications. However, there are some situations where these features can not be used due the application type or unavailability of NLP resources for some of the languages. That is why an application that is intended to handle multilingual texts must have features that are not dependent on a particular language and specific linguistic tools. In this thesis, we will focus on two such applications: text readability and source and translation classification.
In this thesis, we provide 18 features that are not only suitable for both applications, but are also language and linguistic tools independent. In order to build a readability classifier, we use texts from three different languages: English, German and Bangla. Our proposed features achieve a classification accuracy that is comparable with a classifier using 40 linguistic features. The readability classifier achieves a classification F-score of 74.21% on the English Wikipedia corpus, an F-score of 75.47% on the English textbook corpus, an F-score of 86.46% on the Bangla textbook corpus and an F-score of 86.26% on the German GEO/GEOLino corpus.
We used more than two million sentence pairs from 21 European languages in order to build the source and translation classifier. The classifier using the same eighteen features achieves a classification accuracy of 86.63%. We also used the same features to build a classifier that classifies translated texts based on their origin. The classifier achieves classification accuracy of 75% for texts from 10 European languages. In this thesis, we also provide four different corpora, three for text readability analysis and one for corpus based translation studies.
MTO1-deficient mouse model mirrors the human phenotype showing complex I defect and cardiomyopathy
(2014)
Recently, mutations in the mitochondrial translation optimization factor 1 gene (MTO1) were identified as causative in children with hypertrophic cardiomyopathy, lactic acidosis and respiratory chain defect. Here, we describe an MTO1-deficient mouse model generated by gene trap mutagenesis that mirrors the human phenotype remarkably well. As in patients, the most prominent signs and symptoms were cardiovascular and included bradycardia and cardiomyopathy. In addition, the mutant mice showed a marked worsening of arrhythmias during induction and reversal of anaesthesia. The detailed morphological and biochemical workup of murine hearts indicated that the myocardial damage was due to complex I deficiency and mitochondrial dysfunction. In contrast, neurological examination was largely normal in Mto1-deficient mice. A translational consequence of this mouse model may be to caution against anaesthesia-related cardiac arrhythmias which may be fatal in patients.
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).
Money is more than memory
(2014)
Impersonal exchange is the hallmark of an advanced society. One key institution for impersonal exchange is money, which economic theory considers just a primitive arrangement for monitoring past conduct in society. If so, then a public record of past actions — or memory — supersedes the function performed by money. This intriguing theoretical postulate remains untested. In an experiment, we show that the suggested functional equality between money and memory does not translate into an empirical equivalence. Monetary systems perform a richer set of functions than just revealing past behaviors, which proves to be crucial in promoting large-scale cooperation.
This paper investigates the role of monetary policy in the collapse in the long-term real interest rates in the decade before the onset of the financial crisis using a sample of five advanced economies (United States, United Kingdom, the euro area, Sweden and Canada). The results from an estimated panel VAR with monthly data show that, while monetary policy shocks had negligible effects on long-term real interest rates, shocks to the long-term real interest rates had a one-to-one effect on the short nominal rate.
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.
In the wake of the Global Financial Crisis that started in 2007, policymakers were forced to respond quickly and forcefully to a recession caused not by short-term factors, but rather by an over-accumulation of debt by sovereigns, banks, and households: a so-called “balance sheet recession.” Though the nature of the crisis was understood relatively early on, policy prescriptions for how to deal with its consequences have continued to diverge. This paper gives a short overview of the prescriptions, the remaining challenges and key lessons for monetary policy.
Transcription factor IIS (TFIIS) is a protein known for catalyzing the cleavage reaction of the 3′-end of backtracked RNA transcript, allowing RNA polymerase II (Pol II) to reactivate the transcription process from the arrested state. Recent structural studies have provided a molecular basis of protein-protein interaction between TFIIS and Pol II. However, the detailed dynamic conformational changes of TFIIS upon binding to Pol II and the related thermodynamic information are largely unknown. Here we use computational approaches to investigate the conformational space of TFIIS in the Pol II-bound and Pol II-free (unbound) states. Our results reveal two distinct conformations of TFIIS: the closed and the open forms. The closed form is dominant in the Pol II-free (unbound) state of TFIIS, whereas the open form is favorable in the Pol II-bound state. Furthermore, we discuss the free energy difference involved in the conformational changes between the two forms in the presence or absence of Pol II. Additionally, our analysis indicates that hydrophobic interactions and the protein-protein interactions between TFIIS and Pol II are crucial for inducing the conformational changes of TFIIS. Our results provide novel insights into the functional interplay between Pol II and TFIIS as well as mechanism of reactivation of Pol II transcription by TFIIS.
Na+/H+ antiporters are integral membrane proteins that are present in almost every cell and in every kingdom of life. They are essential for the regulation of intracellular pH-value, Na+-concentration and cell volume. These secondary active transporters exchange sodium ions against protons via an alternating access mechanism, which is not understood in full detail. Na+/H+ antiporters show distinct species-specific transport characteristics and regulatory properties that correlate with respective physiological functions. Here we present the characterization of the Na+/H+ antiporter NhaA from Salmonella enterica serovar Thyphimurium LT2, the causing agent of food-born human gastroenteritis and typhoid like infections. The recombinant antiporter was functional in vivo and in vitro. Expression of its gene complemented the Na+-sensitive phenotype of an E. coli strain that lacks the main Na+/H+ antiporters. Purified to homogeneity, the antiporter was a dimer in solution as accurately determined by size-exclusion chromatography combined with multi-angle laser-light scattering and refractive index monitoring. The purified antiporter was fully capable of electrogenic Na+(Li+)/H+-antiport when reconstituted in proteoliposomes and assayed by solid-supported membrane-based electrophysiological measurements. Transport activity was inhibited by 2-aminoperimidine. The recorded negative currents were in agreement with a 1Na+(Li+)/2H+ stoichiometry. Transport activity was low at pH 7 and up-regulation above this pH value was accompanied by a nearly 10-fold decrease of KmNa (16 mM at pH 8.5) supporting a competitive substrate binding mechanism. K+ does not affect Na+ affinity or transport of substrate cations, indicating that selectivity of the antiport arises from the substrate binding step. In contrast to homologous E. coli NhaA, transport activity remains high at pH values above 8.5. The antiporter from S. Typhimurium is a promising candidate for combined structural and functional studies to contribute to the elucidation of the mechanism of pH-dependent Na+/H+ antiporters and to provide insights in the molecular basis of species-specific growth and survival strategies.