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The taxonomy of the family Desmodoridae (Nematoda: Desmodorida) is partially revised based on morphology. The diagnoses of the Desmodoridae and the subfamilies Desmodorinae and Spiriniinae are emended to accommodate re-analyzed morphological features. Eight known species are redescribed and the implication of the new findings for the taxonomy of the group is discussed. Amphispira and Metadesmodora are confirmed as genera inquirendae. Alaimonema and Sigmophoranema, and their corresponding type species, are proposed as inquirendae due to poor descriptions of the type material. The other three species of Sigmophoranema are transferred to the genus Onyx because they bear the diagnostic features of this group: spear-like dorsal tooth and s-shape precloacal supplements. Echinodesmodora, Paradesmodora and Stygodesmodora are transferred to the Spiriniinae based on the absence of a head capsule and on the amphidial fovea being surrounded by cuticle striation. Paradesmodora toreutes is transferred to the genus Acanthopharyngoides as A. toreutes comb. nov. The genus Onepunema does not fit in the family Desmodoridae because of diorchic males; thus, it is regarded as taxon incertae sedis.
Lists of valid genera for the two subfamilies are provided. A dichotomic key for the identification of the 14 genera within the Spiriinae is provided.
Antigenic and 3D structural characterization of soluble X4 and hybrid X4-R5 HIV-1 Env trimers
(2014)
Background: HIV-1 is decorated with trimeric glycoprotein spikes that enable infection by engaging CD4 and a chemokine coreceptor, either CCR5 or CXCR4. The variable loop 3 (V3) of the HIV-1 envelope protein (Env) is the main determinant for coreceptor usage. The predominant CCR5 using (R5) HIV-1 Env has been intensively studied in function and structure, whereas the trimeric architecture of the less frequent, but more cytopathic CXCR4 using (X4) HIV-1 Env is largely unknown, as are the consequences of sequence changes in and near V3 on antigenicity and trimeric Env structure.
Results: Soluble trimeric gp140 Env constructs were used as immunogenic mimics of the native spikes to analyze their antigenic properties in the context of their overall 3D structure. We generated soluble, uncleaved, gp140 trimers from a prototypic T-cell line-adapted (TCLA) X4 HIV-1 strain (NL4-3) and a hybrid (NL4-3/ADA), in which the V3 spanning region was substituted with that from the primary R5 isolate ADA. Compared to an ADA (R5) gp140, the NL4-3 (X4) construct revealed an overall higher antibody accessibility, which was most pronounced for the CD4 binding site (CD4bs), but also observed for mAbs against CD4 induced (CD4i) epitopes and gp41 mAbs. V3 mAbs showed significant binding differences to the three constructs, which were refined by SPR analysis. Of interest, the NL4-3/ADA construct with the hybrid NL4-3/ADA CD4bs showed impaired CD4 and CD4bs mAb reactivity despite the presence of the essential elements of the CD4bs epitope. We obtained 3D reconstructions of the NL4-3 and the NL4-3/ADA gp140 trimers via electron microscopy and single particle analysis, which indicates that both constructs inherit a propeller-like architecture. The first 3D reconstruction of an Env construct from an X4 TCLA HIV-1 strain reveals an open conformation, in contrast to recently published more closed structures from R5 Env. Exchanging the X4 V3 spanning region for that of R5 ADA did not alter the open Env architecture as deduced from its very similar 3D reconstruction.
Conclusions: 3D EM analysis showed an apparent open trimer configuration of X4 NL4-3 gp140 that is not modified by exchanging the V3 spanning region for R5 ADA.
Cross-frequency coupling (CFC) has been proposed to coordinate neural dynamics across spatial and temporal scales. Despite its potential relevance for understanding healthy and pathological brain function, the standard CFC analysis and physiological interpretation come with fundamental problems. For example, apparent CFC can appear because of spectral correlations due to common non-stationarities that may arise in the total absence of interactions between neural frequency components. To provide a road map towards an improved mechanistic understanding of CFC, we organize the available and potential novel statistical/modeling approaches according to their biophysical interpretability. While we do not provide solutions for all the problems described, we provide a list of practical recommendations to avoid common errors and to enhance the interpretability of CFC analysis.
Touring Girls
(2014)
Touring Girls tells the story of Jacob Mbuy a young Cameroonian whose primary objective in life is having affairs with as many women as possible. He is obsessed with abusing young girls as well as instilling hopeless hope in adult women. His demise comes when he changes his world from the Christian to the Moslem world where he confronts a new type of women who behave strangely and cannot dance to his tunes. Protected by Islamic traditions and strict government laws, Jacob lands into a hell of unprecedented problems.
If we take Benjamin's definitions to their logical conclusion, then the monad and the reproduced copy are set unequivocally into binary opposition, as we, the masses capable and most needful of action, are implicitly denied the potential for liberation through aesthetic experience. This denial could not have been his long-term intention. When we take into account the breadth of his writings in response to Fascism, and we look at the artistic movements, Dada in particular, that Benjamin defines as 'politicizing art,' it seems as though we risk too narrow a reading of Benjamin's theories by assuming the aura can be, or must be, done away with. Rather, I would argue that this moment of auratic interaction is crucial to effectively politicizing art at all. Mechanically-produced art, in order to function politically, must allow its audience the space necessary to step back, awaken their 'Geistesgegenwart', and take action 'before' the present moment is finished and past. The elimination of aura - as per Benjamin’s own definitions of aura - neuters the interaction this awakening requires. While Benjamin provides the framework and asks the right questions, when determining what will allow his definitions to realize their aims most fully, I submit that he draws his line in the wrong place.
Trends in Nollywood: A Study of Selected Genres is a welcome addition to the growing body of works on the Nigerian cinema. It is part film history and part film theory and criticism. The history part traces the origin of the Nigerian cinema up to the present era of video productions. The work examines in detail, the contextual issues which have helped to define emergent trends within the industry.
Background: Hereditary angioedema (HAE) due to C1 inhibitor deficiency is a rare but serious and potentially life-threatening disease marked by spontaneous, recurrent attacks of swelling. The study objective was to characterize direct and indirect resource utilization associated with HAE from the patient perspective in Europe.
Methods: The study was conducted in Spain, Germany, and Denmark to assess the real-world experience of HAE via a cross-sectional survey of HAE patients, including direct and indirect resource utilization during and between attacks for patients and their caregivers over the past 6 months. A regression model examined predictors of medical resource utilization.
Results: Overall, 164 patients had an attack in the past 6 months and were included in the analysis. The most significant predictor of medical resource utilization was the severity of the last attack (OR 2.6; p < 0.001). Among patients who sought medical care during the last attack (23%), more than half utilized the emergency department. The last attack prevented patients from their normal activities an average of 4-12 hours. Patient and caregiver absenteeism increased with attack severity and frequency. Among patients who were working or in school (n = 120), 72 provided work/school absenteeism data, resulting in an estimated 20 days missing from work/school on average per year; 51% (n = 84) indicated that HAE has hindered their career/educational advancement.
Conclusion: HAE poses a considerable burden on patients and their families in terms of direct medical costs and indirect costs related to lost productivity. This burden is substantial at the time of attacks and in between attacks.
Feathers in Reverse
(2014)
Feathers in Reverse is the ideal gift for a loved one who is scared of poetry. It engages and immerses readers with the luring subtlety of a serpent. Themes treated include good and evil, heaven and earth, man and woman, birth and death, urbanism and rural life, wealth and poverty. As much as the poet highlights salient issues and conflicts in everyday life, he suggests answers to burning problems as well. A common thread runs through the over 300 poems feathered and featured in this collection. The notion of the 'feather' is cross-cultural. It reminds us of the feather used as a pen in ancient Europe and the 'red feather' that is stuck on the caps of African notables as a mark of distinction. Feathers in Reverse is a magic pudding to be sampled, shared and indulged.
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.
An extensive survey of the relevant literature of dry grassland communities described for the territory of Serbia allowed us to check the validity and legitimacy of the nomenclature of this vegetation. Nomenclature rules of the International Code of Phytosociological Nomenclature were strictly followed. The syntaxonomic affiliation of communities to higher syntaxa was assessed according to existing syntaxonomic schemes for Serbia and the position determined by the original source. Higher syntaxa followed the synsystem of the socalled “EuroVegChecklist”. We have highlighted problems and some disagreement with the existing classification of dry grassland communities in Europe. A total of 134 dry grassland communities have so far been registered for Serbia. This list of syntaxa may serve for further research of grassland vegetation and its appropriate positioning within a syntaxonomical scheme of Europe.
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.
Quarks and gluons are the building blocks of all hadronic matter, like protons and neutrons. Their interaction is described by Quantum Chromodynamics (QCD), a theory under test by large scale experiments like the Large Hadron Collider (LHC) at CERN and in the future at the Facility for Antiproton and Ion Research (FAIR) at GSI. However, perturbative methods can only be applied to QCD for high energies. Studies from first principles are possible via a discretization onto an Euclidean space-time grid. This discretization of QCD is called Lattice QCD (LQCD) and is the only ab-initio option outside of the high-energy regime. LQCD is extremely compute and memory intensive. In particular, it is by definition always bandwidth limited. Thus—despite the complexity of LQCD applications—it led to the development of several specialized compute platforms and influenced the development of others. However, in recent years General-Purpose computation on Graphics Processing Units (GPGPU) came up as a new means for parallel computing. Contrary to machines traditionally used for LQCD, graphics processing units (GPUs) are a massmarket product. This promises advantages in both the pace at which higher-performing hardware becomes available and its price. CL2QCD is an OpenCL based implementation of LQCD using Wilson fermions that was developed within this thesis. It operates on GPUs by all major vendors as well as on central processing units (CPUs). On the AMD Radeon HD 7970 it provides the fastest double-precision D= kernel for a single GPU, achieving 120GFLOPS. D=—the most compute intensive kernel in LQCD simulations—is commonly used to compare LQCD platforms. This performance is enabled by an in-depth analysis of optimization techniques for bandwidth-limited codes on GPUs. Further, analysis of the communication between GPU and CPU, as well as between multiple GPUs, enables high-performance Krylov space solvers and linear scaling to multiple GPUs within a single system. LQCD calculations require a sampling of the phase space. The hybrid Monte Carlo (HMC) algorithm performs this. For this task, a single AMD Radeon HD 7970 GPU provides four times the performance of two AMD Opteron 6220 running an optimized reference code. The same advantage is achieved in terms of energy-efficiency. In terms of normalized total cost of acquisition (TCA), GPU-based clusters match conventional large-scale LQCD systems. Contrary to those, however, they can be scaled up from a single node. Examples of large GPU-based systems are LOEWE-CSC and SANAM. On both, CL2QCD has already been used in production for LQCD studies.
Recent density functional theory (DFT) calculations for KFe2As2 have been shown to be insufficient to satisfactorily describe angle-resolved photoemission (ARPES) measurements as well as observed de Haas–van Alphen (dHvA) frequencies. In the present work, we extend DFT calculations based on the full-potential linear augmented plane-wave method by dynamical mean field theory (DFT+DMFT) to include correlation effects beyond the local density approximation. We present results for two sets of reported crystal structures. Our calculations indicate that KFe2As2 is a moderately correlated metal with a mass renormalization factor of the Fe $3{\rm d}$ orbitals between 1.6 and 2.7. Furthermore, the obtained shape and size of the Fermi surface are in good agreement with ARPES measurements and we observe some topological changes with respect to DFT calculations such as the opening of an inner hole cylinder at the Z point. As a result, our calculated dHvA frequencies differ greatly from existing DFT results and qualitatively agree with experimental data. On this basis, we argue that correlation effects are important to understand the -presently under debate- nature of the superconducting state in KFe2As2.
Previous research has documented strong peer effects in risk taking, but little is known about how such social influences affect market outcomes. The consequences of social interactions are hard to isolate in financial data, and theoretically it is not clear whether peer effects should increase or decrease risk sharing. We design an experimental asset market with multiple risky assets and study how exogenous variation in real-time information about the portfolios of peer group members affects aggregate and individual risk taking. We find that peer information ameliorates under-diversification that occurs in a market without such information. One reason is that peer information increases risk aversion and induces a concern for relative income position that may reduce or amplify risk taking, depending on whether the context highlights the most or least successful trader. Thus, contrary to conventional wisdom, we show that social interactions may help to reduce earnings volatility in financial markets, and we discuss implications for institutional design.
We investigate the relationship between anchoring and the emergence of bubbles in experimental asset markets. We show that setting a visual anchor at the fundamental value (FV) in the first period only is sufficient to eliminate or to significantly reduce bubbles in laboratory asset markets. If no FV-anchor is set, bubble-crash patterns emerge. Our results indicate that bubbles in laboratory environments are primarily sparked in the first period. If prices are initiated around the FV, they stay close to the FV over the entire trading horizon. Our insights can be related to initial public offerings and the interaction between prices set on pre-opening markets and subsequent intra-day price dynamics.
“WAR IS PEACE, FREEDOM IS SLAVERY, AND IGNORANCE IS STRENGTH”. The slogan from George Orwell’s “1984” dystopia appears to capture the state of Russia’s 2014 official discourse quite accurately. This has not gone unnoticed by public and academic spectators in and outside Russia: while Bild magazine is counting Putin’s lies in his recent ARD interview, a Zeit article declares Russia itself to be a post-modern “lie”...
This paper examines the effect of imperfect labor market competition on the efficiency of compensation schemes in a setting with moral hazard, private information and risk-averse agents. Two vertically differentiated firrms compete for agents by offering contracts with fixed and variable payments. Vertical differentiation between firms leads to endogenous, type-dependent exit options for agents. In contrast to screening models with perfect competition, we find that existence of equilibria does not depend on whether the least-cost separating allocation is interim efficient. Rather, vertical differentiation allows the inferior firm to offer (cross-)subsidizing fixed payments even above the interim efficient level. We further show that the efficiency of variable pay depends on the degree of competition for agents: For small degrees of competition, low-ability agents are under-incentivized and exert too little effort. For large degrees of competition, high-ability agents are over-incentivized and bear too much risk. For intermediate degrees of competition, however, contracts are second-best despite private information.
This paper studies the use of performance pricing (PP) provisions in debt contracts and compares accounting-based with rating-based pricing designs. We find that rating-based provisions are used by volatile-growth borrowers and allow for stronger spread increases over the credit period. Accounting-based provisions are employed by opaque-growth borrowers and stipulate stronger spread reductions. Further, a higher spread-increase potential in rating-based contracts lowers the spread at the loan’s inception and improves the borrower’s performance later on. In contrast, a higher spread-decrease potential in accounting-based contracts lowers the initial spread and raises the borrower’s leverage afterwards. The evidence indicates that rating-based contracts are indeed employed for different reasons than accounting-based contracts: the former to signal a borrower’s quality, the latter to mitigate investment inefficiencies.
Based on a non-rigorous formalism called the “cavity method”, physicists have made intriguing predictions on phase transitions in discrete structures. One of the most remarkable ones is that in problems such as random k-SAT or random graph k-coloring, very shortly before the threshold for the existence of solutions there occurs another phase transition called condensation [Krzakala et al., PNAS 2007]. The existence of this phase transition seems to be intimately related to the difficulty of proving precise results on, e. g., the k-colorability threshold as well as to the performance of message passing algorithms. In random graph k-coloring, there is a precise conjecture as to the location of the condensation phase transition in terms of a distributional fixed point problem. In this paper we prove this conjecture, provided that k exceeds a certain constant k0.