julilili42/papers huggingface dataset:
Properties of face localizer activations and their application in functional magnetic resonance imaging (fMRI) fingerprinting
2019-04-23

Functional localizers are particularly prevalent in functional magnetic resonance imaging (fMRI) studies concerning face processing. In this study, we extend the knowledge on face localizers regarding four important aspects: First, activation differences in occipital and fusiform face areas (OFA/FFA) and amygdala are characterized by increased activation while precuneus and medial prefrontal cortex show decreased deactivation to faces versus control stimuli. The face-selective posterior superior temporal sulcus is a hybrid area exhibiting increased activation within its inferior and decreased deactivation within its superior part. Second, the employed control stimuli can impact on whether a region is classified in group analyses as face-selective or not. We specifically investigated this for recently described cytoarchitectonic subregions of the fusiform cortex (FG-2/FG-4). Averaged activity across voxels in FG-4 was stronger for faces than objects, houses, or landscapes. In FG-2, averaged activity was only significantly stronger in comparison with landscapes, but small peaks within this area were detected for comparison versus objects and houses. Third, reproducibility of individual peak activations is excellent for right FFA and quite good for right OFA, whereas within all other areas it was too low to provide valid information on time-invariant individual peaks. Finally, the fine-grained spatial activation patterns in right OFA and FFA are both time-invariant within each individual and sufficiently different between individuals to enable identification of individual participants with near-perfect precision (fMRI fingerprinting).
Spatial and temporal variation in river corridor exchange across a 5th order mountain stream network
2019-04-23

Abstract. Although most field and modeling studies of river corridor exchange have been conducted a scales ranging from 10’s to 100’s of meters; results of these studies are used to predict their ecological and hydrological influences at the scale of river networks. Further complicating prediction, exchange are expected to vary with hydrologic forcing and the local geomorphic setting. While we desire predictive power, we lack a complete spatiotemporal relationship relating discharge to the variation in geologic setting and hydrologic forcing that are expected across a river basin. Indeed, Wondzell’s [2011] conceptual model predicts systematic variation in river corridor exchange as a function of (1) variation in discharge over time at a fixed location, (2) variation in discharge with location in the river network, and (3) local geomorphic setting. To test this conceptual model we conducted more than 60 solute tracer studies collected in a synoptic campaign in the 5th order river network of the H. J. Andrews Experimental Forest (Oregon, USA). We interpret the data using a series of metrics describing river corridor exchange and solute transport, testing for consistent direction and magnitude of relationships relating these metrics to discharge and local geomorphic setting. We confirmed systematic decrease in river corridor exchange space through the river networks, from headwaters to the larger mainstem. However, we did not find systematic variation with changes in discharge through time, nor with local geomorphic setting. While interpretation of our results are complicated by problems with the analytical methods, they are sufficiently robust for us to conclude that space-for-time and time-for-space substitutions are not appropriate in our study system. Finally, we suggest two strategies that will improve the interpretability of tracer test results and help the hyporheic community develop robust data sets that will enable comparisons across multiple sites and/or discharge conditions.
The Physics of Accretion Onto Highly Magnetized Neutron Stars
2019-04-23

Studying the physical processes occurring in the region just above the magnetic poles of strongly magnetized, accreting binary neutron stars is essential to our understanding of stellar and binary system evolution. Perhaps more importantly, it provides us with a natural laboratory for studying the physics of high temperature and high density plasmas exposed to extreme radiation, gravitational, and magnetic fields. Observations over the past decade have shed new light on the manner in which plasma falling at velocities near the speed of light onto a neutron star surface is halted. Recent advances in modeling these processes have resulted in direct measurement of the magnetic fields and plasma properties. On the other hand, numerous physical processes have been identified that challenge our current picture of how the accretion process onto neutron stars works. Observation and theory are our essential tools in this regime because the extreme conditions cannot be duplicated on Earth. This white paper gives an overview of the current theory, the outstanding theoretical and observational challenges, and the importance of addressing them in contemporary astrophysics research.
Prey‐to‐fox isotopic enrichment of 34 S in bone collagen: Implications for paleoecological studies
2019-04-24

Rationale The trophic enrichment factor (TEF) is a parameter reflecting the difference in isotopic ratio between a consumer's tissues and diet, used in isotopic ecology and paleoecology to track dietary habits. The TEF of sulfur is believed to be low, but was, until now, only documented in a limited number of taxa. In this study we use a subfossil accumulation of bones from a red fox ( Vulpes vulpes ) den to verify the TEF for sulfur in fox bone collagen. Methods Collagen was extracted from 30 samples of subfossil bones, including foxes and their prey. The δ 34 S values of the bone collagen samples were measured with an elemental analyzer connected to an isotope ratio mass spectrometer. The TEF was calculated as [Δ 34 S = (mean δ 34 S in predator) – (mean δ 34 S in prey)], using taphonomic indices to estimate the mean diet, and calculated separately for different age classes of the predator. Results We modeled 12 variants of TEF for different estimations of the diet composition and for three fox age classes (adult, subadult, and juvenile). The estimated TEF values range from −0.54 to +0.03‰ and are similar to TEFs known for other mammals. Absolute TEF values are nearly equal to or lower than the analytical error, which is ±0.4‰. Conclusions For the first time, we present direct δ 34 S data for the bone collagen of a free‐living predator and its naturally selected prey. Our results indicate very low or even slightly negative TEF values for sulfur. Furthermore, according to our results, the δ 34 S value should not be considered a reliable indicator of trophic position in terrestrial food webs but rather, it should be used to disentangle different food webs based on different primary producers.
Analysing the context-specific relevance of competencies – sport management alumni perspectives
2019-04-24

Research question Recent studies on occupational fields show that different competencies are considered important in different work environments. However, with regard to sport management, there is a lack of knowledge about how context matters in terms of required competencies. This study examines how specific patterns of competencies are associated with sport management alumni's occupational context.Research methods 142 alumni of a bachelor and master programme in sport management who already have entered professional life participated in an online survey which comprised questions on the relevance of skills/abilities related to four competency dimensions and on the occupational context. Probit models were employed to analyse the association of context factors and the job-related relevance of competencies.Results and findings Results suggest that 'context' plays a role in the sport managers' assessment of the relevance of most competencies. For example, working in a private not-for-profit organisation is associated with rating 'load capacity', 'negotiating skills', and 'assertiveness' as relevant competencies, but 'use of scientific methods' and 'scientific writing' are considered less relevant. Furthermore, the work tasks 'budgeting' 'coaching', and 'data analysis' are associated with the most specific patterns of competency.Implications Organisation and communication skills contribute to general employability of graduates. Beyond that, and due to occupation-specific competency requirements, contextual frameworks of employment and the characteristics of work-related situations need to be considered, for example in teaching-learning processes.
Character, Rates, and Environmental Significance of Holocene Dust Accumulation in Archaeological Hilltop Ruins in the Southern Levant
2019-04-24

Loess accumulated in the Negev desert during the Pleistocene and primary and secondary loess remains cover large parts of the landscape. Holocene loess deposits are however absent. This could be due low accumulation rates, lack of preservation, and higher erosion rates in comparison to the Pleistocene. This study hypothesized that archaeological ruins preserve Holocene dust. We studied soils developed on archaeological hilltop ruins in the Negev and the Petra region and compared them with local soils, paleosols, geological outcrops, and current dust. Seven statistically modeled grain size end-members were identified and demonstrate that the ruin soils in both regions consist of mixtures of local and remote sediment sources that differ from dust compositions deposited during current storms. This discrepancy is attributed to fixation processes connected with sediment-fixing agents such as vegetation, biocrusts, and/or clast pavements associated with vesicular layers. Average dust accretion rates in the ruins are estimated to be ~0.14 mm/a, suggesting that ~30% of the current dust that can be trapped with dry marble dust collectors has been stored in the ruin soils. Deposition amounts and grain sizes do not significantly correlate with wind intensity. However, precipitation may have contributed to dust accretion. A snowstorm in the Petra region delivered a significantly higher amount of sediment than rain or dry deposition. Snowfall dust had a unique particle size distribution relatively similar to the ruin soils. Wet deposition and snow might catalyze dust deposition and enhance fixation by fostering vegetation and crust formation. More frequent snowfall during the Pleistocene may have been an important mechanism of primary loess deposition in the southern Levant.
SOPH syndrome in three affected individuals showing similarities with progeroid cutis laxa conditions in early infancy
2019-04-24

Individuals affected with autosomal recessive cutis laxa type 2B and 3 usually show translucent skin with visible veins and abnormal elastic fibers, intrauterine and/or postnatal growth restriction and a typical triangular facial gestalt. Here we describe three unrelated individuals in whom such a cutis laxa syndrome was suspected, especially after electron microscopy revealed immature and less dense dermal elastic fibers in one of them. However, one of these children also displayed optic atrophy and two hypogammaglobulinemia. All had elevated liver enzymes and acute liver failure during febrile episodes leading to early demise in two of them. The only surviving patient had been treated with immunoglobulins. Through exome sequencing we identified mutations in NBAS, coding for a protein involved in Golgi-to-ER transport. NBAS deficiency causes several rare conditions ranging from isolated recurrent acute liver failure to a multisystem disorder mainly characterized by short stature, optic nerve atrophy and Pelger-Huët anomaly (SOPH). Since we subsequently verified Pelger-Huët anomaly in two of the patients the diagnosis SOPH syndrome was unequivocally proven. Our data show that SOPH syndrome can be regarded as a differential diagnosis for the progeroid forms of cutis laxa in early infancy and that possibly treatment of the hypogammaglobulinemia can be of high relevance for the prognosis.
The Impact of Problem Order: Sequencing Problems as a Strategy for Improving One s Performance
2019-04-24

Two experiments investigated the impact of problem order and problem sequencing on performance. In experiment 1 subjects were either presented with a suitable or an unsuitable presentation sequence where they were free to deviate from. Presentation sequence had an impact on performance and rearranging problems improved performance for high prior-knowledge subjects whereas low prior-knowledge subjects' performance deteriorated. Experiment 2 yielded evidence that effects of problem sequence have to be triggered by directing subjects' attention to comparing problems before working on them. Results are discussed within the framework of analogical transfer.
Electronically Tuned Asymmetric meso‐Substituted Porphyrins for p‐Type Solar Cells
2019-04-24

Abstract A series of electronically tuned asymmetric porphyrins have been synthesized for use in p‐type solar cells. The porphyrin derivatives were strategically designed with electron‐withdrawing capability and an electronic dipole gradient to aid in electron‐harvesting capacity from a nickel oxide cathode. Specifically, the porphyrins were substituted at the meso position with different arrangements of the electron‐withdrawing pentafluorobenzene moiety, electron‐donating/coordinating 4‐pyridyl ligand, and an electron withdrawing/synthetically modifiable 4‐cyanophenyl unit. Two distinct free‐base porphyrins were synthesized, one of which was further metallated with nickel(II). The porphyrins were fully characterized and their electronic properties explored experimentally by electrochemistry, and both steady state and time‐resolved spectroscopy. Finally, the porphyrins were incorporated into a p‐type solar cell device utilizing NiO as the cathode, and demonstrating a preliminary maximum performance of η (%)=0.082 and IPCE MAX (%)=26.0 without co‐sensitization.
A Signature of Passivity? An Explorative Study of the N3 Event- Related Potential Component in Passive Oddball Tasks
2019-04-24

We discuss the similarities and differences between the passive N3 and other components including the MMN, N1, late positive Slow Wave, and reorienting negativity. We also make general hypotheses about a possible functional meaning of N3; on this basis, specific hypotheses are formulated and further experiments are suggested to test these hypotheses.
Global Sensitivity Analysis and Adaptive Stochastic Sampling of a Subsurface-Flow Model Using Active Subspaces
2019-04-24

Abstract. Integrated hydrological modelling of domains with complex subsurface features requires many highly uncertain parameters. Performing a global uncertainty analysis using an ensemble of model runs can help bring clarity which of these parameters really influence system behavior, and for which high parameter uncertainty does not result in similarly high uncertainty of model predictions. However, already creating a sufficiently large ensemble of model simulation for the global sensitivity analysis can be challenging, as many combinations of model parameters can lead to unrealistic model behavior. In this work we use the method of active subspaces to perform a global sensitivity analysis. While building-up the ensemble, we use the already existing ensemble members to construct low-order meta-models based on the first two active subspace dimensions. The meta-models are used to pre-determine whether a random parameter combination in the stochastic sampling is likely to result in unrealistic behavior, so that such a parameter combination is excluded without running the computationally expensive full model. An important reason for choosing the active subspace method is that both the activity score of the global sensitivity analysis and the meta-models can easily be understood and visualized. We test the approach on a subsurface flow model including uncertain hydraulic parameter, uncertain boundary conditions, and uncertain geological structure. We show that sufficiently detailed active subspaces exist for most observations of interest. The pre-selection by the meta-model significantly reduces the number of full model runs that must be rejected due to unrealistic behavior. An essential but difficult part in active subspace sampling using complex models is approximating the gradient of the simulated observation with respect to all parameters. We show that this can effectively and meaningful be done with second-order polynomials.
Revisiting the regulation of the capsular polysaccharide biosynthesis gene cluster inStaphylococcus aureus
2019-04-24

Abstract In Staphylococcus aureus , the capsular polysaccharide (CP) protects against phagocytosis, but also hinders adherence to endothelial cells and matrix proteins. Its biosynthesis is tightly controlled resulting in a heterogeneous phenotype within a population and CP being mainly detectable in non-growing cells. Capsular biosynthesis genes are encoded by a conserved capA-P operon whose expression is driven by an upstream promoter element (P cap ) in front of capA . The organization of P cap is poorly understood, as is the interplay of different regulators that influence the early-Off/late-Heterogeneous cap transcription pattern. Here, we demonstrate that P cap contains a main SigB-dependent promoter. The SigB consensus motif overlaps with a previously described inverted repeat that is crucial for cap expression. The essentiality of the inverted repeat is derived from this region acting as a SigB binding site rather than as an operator site for the proposed cap activators RbsR and MsaB. Furthermore, P cap contains an extensive upstream region harboring a weak SigA-dependent promoter and binding sites for the cap repressors SaeR, CodY and Rot. We show that heterogeneous CP synthesis is determined by the combination of SigB activity and repressor binding to the upstream region. The direct SigB dependency and the upstream repressors are also sufficient to explain the temporal gene expression pattern at the transcriptional level. However, CP synthesis remains growth phase-dependent even when capA transcription is rendered constitutive, suggesting additional post-transcriptional regulatory circuits. Thus, the interference of multiple repressors with SigB-dependent promoter activity as well as post-transcriptional mechanisms ensure the appropriate regulation of CP synthesis. Importance The majority of bacterial pathogens produce an array of polysaccharides on their surface which are important virulence factors and thus serve as attractive vaccine candidates. However, the synthesis and assembly of these structures is highly variable and tightly regulated at various levels. In the human pathogen Staphylococcus aureus , the synthesis of the capsular polysaccharide (CP) is dependent on a complex regulatory network which ensures that CP is produced only in a fraction of stationary phase cells. Here, we determined main regulators that drive the peculiar CP expression pattern. We found that the interplay of the transcriptional repressors Sae, CodY and Rot with the alternative Sigma factor B is responsible for early-Off/late-Heterogeneous expression at the transcriptional level. The data also implicates post-transcriptional mechanisms that may act to avoid conflict in precursor usage by machineries involved in either synthesis of CP or other glycopolymers in growing bacterial cells.
Co-located contemporaneous mapping of morphological,hydrological, chemical, and biological conditions in a 5th ordermountain stream network, Oregon, USA
2019-04-24

Abstract. A comprehensive set of measurements and calculated metrics describing physical, chemical, and biological conditions in the river corridor is presented. These data were collected in a catchment-wide, synoptic campaign in Lookout Creek within the H.J. Andrews Experimental Forest (Cascade Mountains, Oregon, USA) in summer 2016 during low discharge conditions. Extensive characterization of 62 sites including surface water, hyporheic water, and streambed sediment was conducted spanning 1st through 5th order reaches in the river network. The objective of the sample design and data acquisition was to generate a novel data set to support scaling of river corridor processes across varying flows and morphologic forms present in a river network. The data are available at http://www.hydroshare.org/resource/f4484e0703f743c696c2e1f209abb842 (Ward, 2019).
Subtle variations in mobbing calls are predator-specific in great tits (Parus major)
2019-04-25

Abstract Many species are known to use vocalizations to recruit con- and heterospecifics to mobbing events. In birds, the vocalizations of the Family Paridae (titmice, tits and chickadees) are well-studied and have been shown to recruit conspecifics and encode information about predation risk. Species use the number of elements within a call, call frequency or call type to encode information. We conducted a study with great tits ( Parus major ) in the field where we presented taxidermy mounts of two predators of different threat levels (tawny owl, Strix aluco , and sparrowhawk, Accipiter nisus ) and compared the mobbing calls of these two contexts. We hypothesized, based on results of studies in other paridae species, that tits vary the number or type of elements of a call according to predatory context. We found great tits to vary the number of D elements and the interval between those elements. Great tits produced significantly longer D calls with more elements and longer intervals between elements when confronted with a sparrowhawk (high-threat) compared to a tawny owl (low-threat) mount. Furthermore, birds produced more D calls towards the high-threat predator. This suggests that the basic D calls are varied depending on threat intensity.
Increased KLRG1 and PD-1 expression on CD8 T lymphocytes in TB-IRIS
2019-04-25

TB-IRIS is preceded by a high level of exhausted (KLRG1+PD-1+) CD8hi T cells, which persists during 3 months of ART. This trait is potentially mirrored in a subpopulation of NK cells, but not CD4+ T cells. Since a dysfunctional CD8+ lymphocyte compartment could predispose patients to TB-IRIS, the functional role of these cells prior to TB-IRIS development should be further explored.
A virtual assessment of the proposed suprainiac fossa on the early modern European calvaria from Cioclovina, Romania
2019-04-25

Abstract Objectives The calvaria from Cioclovina (Romania) has been argued to possess some traits commonly ascribed to individuals belonging to the Neanderthal lineage, including a suprainiac fossa. However, its supranuchal morphology has only been evaluated with a qualitative analysis of the ectocranial surface. We evaluate whether the morphology of the supranuchal area of this specimen is homologous to the Neanderthal condition. Materials and Methods We described in detail the external morphology, and, using computed tomography, investigated the internal morphology of the Cioclovina supranuchal area. We took measurements of the internal structures and calculated their relative contributions to total cranial vault thickness, which were compared to published data and evaluated with a principal component analysis (PCA). Results The Cioclovina supranuchal region is characterized by superficial resorption present on the outer layer of the external table. Neither the diploic layer nor the external table decrease in relative thickness in the area above inion. In the PCA, Cioclovina falls within the convex hulls of recent modern Homo sapiens . Discussion Our results show that the morphology of the Cioclovina supranuchal region does not correspond to the external and internal morphology of the typical Neanderthal suprainiac fossa. It cannot be characterized as a depression but rather as an area presenting superficial bone turnover. Together with earlier results, there is little phenotypic evidence that Cioclovina has high levels of Neanderthal ancestry. Our study demonstrates the usefulness of this quantitative method in assessing proposed Neanderthal‐like suprainiac depressions in Upper Paleolithic and other fossil specimens.