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Since its first application as a substrate for graphene field effect transistors (FETs), hexagonal boron nitride (hBN) has become a prominent component in two-dimensional (2D) material devices. In addition, hBN has been shown to host defects that can be manipulated to change the electronic properties of adjacent 2D materials. Despite the wide use of such defect manipulations, no focused efforts have been made to further the understanding of defect excitations and their influence in graphene/hBN FETs. In this study, we explore the effect of high electric fields (∼ 10 V / nm) on graphene/hBN FETs and find that persistent and reversible shifts in graphene's charge neutrality point (CNP) occur. By increasing the applied electric field and temperature of our device, we find that this CNP shift is enhanced. With this insight, we propose a mechanism that explains these observations based on Poole–Frenkel emissions from defects in hBN. Finally, we show that such an effect may be suppressed by using graphite as a backgate, thus preventing unintended changes in the electrical properties of graphene/hBN FETs. [ABSTRACT FROM AUTHOR]

Background: CD151 is a cell-surface molecule of the tetraspanin family. Its lateral interaction with laminin-binding integrin ɑ3β1 is important for podocyte adhesion to the glomerular basement membrane (GBM). Deletion of Cd151 in mice induces glomerular dysfunction, with proteinuria and associated focal glomerulosclerosis, disorganisation of GBM and tubular cystic dilation. Despite this, CD151 is not routinely screened for in patients with nephrotic-range proteinuria. We aimed to better understand the relevance of CD151 in human kidney disease. Methods: Next-generation sequencing (NGS) was used to detect the variant in CD151. Electron and light microscopy were used to visualise the filtration barrier in the patient kidney biopsy, and immunoreactivity of patient red blood cells to anti-CD151/MER2 antibodies was performed. Further validation of the CD151 variant as disease-causing was performed in zebrafish using CRISPR-Cas9. Results: We report a young child with nail dystrophy and persistent urinary tract infections who was incidentally found to have nephrotic-range proteinuria. Through targeted NGS, a novel, homozygous truncating variant was identified in CD151, a gene rarely reported in patients with nephrotic syndrome. Electron microscopy imaging of patient kidney tissue showed thickening of GBM and podocyte effacement. Immunofluorescence of patient kidney tissue demonstrated that CD151 was significantly reduced, and we did not detect immunoreactivity to CD151/MER2 on patient red blood cells. CRISPR-Cas9 depletion of cd151 in zebrafish caused proteinuria, which was rescued by injection of wild-type CD151 mRNA, but not CD151 mRNA containing the variant sequence. Conclusions: Our results indicate that a novel variant in CD151 is associated with nephrotic-range proteinuria and microscopic haematuria and provides further evidence for a role of CD151 in glomerular disease. Our work highlights a functional testing pipeline for future analysis of patient genetic variants. A higher resolution version of the Graphical abstract is available as Supplementary information [ABSTRACT FROM AUTHOR]

We show that a strong well‐based cylindrical algebraic decomposition P of a bounded semi‐algebraic set S is a regular cell decomposition, in any dimension and independently of the method by which P is constructed. Being well‐based is a global condition on P that holds for the output of many widely used algorithms. We also show the same for S of dimension at most 3 and P a strong cylindrical algebraic decomposition that is locally boundary simply connected: this is a purely local extra condition. [ABSTRACT FROM AUTHOR]

Phenological shifts are expected to affect species interactions, in part by influencing which size classes, life stages or species occur simultaneously in a community. Yet, changes in phenology beyond shifts to the first, mean or median date of an ontogenetic event are underexplored in their importance to community dynamics. Using outdoor mesocosms, we experimentally mimicked increasing variability in breeding phenology of a top predatory salamander in pond food webs (Ambystoma annulatum) to assess its impacts on its own demographic traits and survival. We also tested whether variability in predator breeding would cascade to impact survival and diversity of lower trophic levels (intermediate salamander predators, anuran tadpoles, zooplankton and periphyton). We found that only variability in body size at metamorphosis of A. annulatum was impacted by phenological manipulations, with size variability being greater at higher levels of phenological variability. Because size at metamorphosis is often correlated with adult fitness, covarying variability in body size and phenology may lead to altered population dynamics. We also found that the density and size of A. annulatum were better predictors of overall survival and diversity of amphibian prey compared to phenological variability. We speculate that overwintering mortality of A. annulatum due to pond freezing modulated the impacts of phenological variability, such that changes in demographic traits and cascading effects throughout the food web were mollified. [ABSTRACT FROM AUTHOR]

Synchrotron X-ray imaging has been used to examine in situ the deformation of dendrites that takes place during the solidification of a nickel-based superalloy. By combining absorption and diffraction contrast imaging, deformation events could be classified by their localization and permanence. In particular, a deformation mechanism arising from thermal contraction in a temperature gradient was elucidated through digital image correlation. It was concluded that this mechanism may explain the small misorientations typically observed in single crystal castings. [ABSTRACT FROM AUTHOR]

A bubble gauge was compared with the tripod method and the use of multiple lines for recording the path of placement of a removable partial denture on a cast. The bubble gauge proved to be more accurate and quicker than the other methods, and it was preferred by both technicians and clinicians. [ABSTRACT FROM AUTHOR]

Describes the theoretical determination of the magnetic structure of surfaces within the local spin-density (LSD) formalism. Information on surface physics; Description of the density functional theory; Aspects of solving the LSD equations; Discussion on the ferromagnetic iron(001) surface.

We describe a simple method for detecting formaldehyde using low resolution non-dispersive UV absorption spectroscopy. A two channel sensor was developed, making use of a strong absorption peak at 339 nm and a neighboring region of negligible absorption at 336 nm as a reference. Using a modulated UV LED as a light source and narrow laser-line filters to select the desired spectral bands, a simple detection system was constructed specifically targeted at formaldehyde. By paying particular attention to sources of noise, a minimum detectable absorbance of 5\times 10^-5 absorbance units (AU) was demonstrated with a 20 s averaging period (as \Delta I/I0 ). The system was tested with formaldehyde finding a limit of detection of 4.3 ppm for a 195 mm gas cell. As a consequence of the low gas flow rates used in our test system, a time period of over 8 min was used in further tests, which increased the minimum detectable absorbance to 2\times 10^-4 AU, 17 ppm of formaldehyde. The increase was the result of thermal drift caused by unwanted temperature variation of the UV LED and the filters, resulting in a zero uncertainty estimated at −560 ppm °C−1 and 100 ppm °C−1 respectively. [ABSTRACT FROM PUBLISHER]

Temperature elevation due to climate change is directly altering organismal performance and distributions, but the mechanisms behind these shifts require additional attention. Because small aquatic ectotherms are proposed to perform better at future climates, it is possible that competitive interactions in size-structured communities may also shift. To study the interactive effects of climate and competition on species performance, we evaluated body condition of small and large desmognathan salamanders at current and elevated temperatures in stream mesocosms, and characterized habitat use. In situ evaluation of capture locations demonstrated that the widespread and larger species, Desmognathus conanti, competitively excludes the smaller more narrowly distributed, D. abditus, from stream centers and cooler temperatures, but ex situ mesocosm experiments indicated an interaction between temperature and intra- versus inter-specific competition on D. abditus body condition. At current temperatures, D. abditus body condition increased in the presence of the larger D. conanti, but at elevated temperatures, D. abditus body condition tended to decline in the presence of the larger species relative to intraspecific competitors. We also noted that individuals at future temperatures prioritized growth differently than individuals at current temperatures by shifting allocations away from growth in length to growth in mass consistent with responses of other organisms to stressful conditions that could result in declining reproductive rates. This study demonstrates that processes in size-structured communities may interact with temperature to affect species' future success. [ABSTRACT FROM AUTHOR]

Although red tides are typically formed by dinoflagellate blooms, aloricate ciliates in the genus Mesodinium also produce striking red blooms throughout the world. In mid-March 2015, we confirmed the occurrence of dense blooms of Mesodinium major in Lough Hyne Marine Nature Reserve, a fully marine sea lough in County Cork, SW Ireland. Daytime aggregations of these highly mobile ciliates occurred in the surface and subsurface waters of the lough, particularly along the western shore and in the Goleen. Fine-scale comparisons of dissolved oxygen (DO) and water temperature values indicated that the surface water supporting dense blooms was slightly but significantly more oxygenated and warmer than closely juxtaposed water without visible blooms. Coarse-scale comparisons, however, showed no significant difference in DO or temperature between bloom and non-bloom areas, although there were highly significant differences in the two parameters by water depth and location within the lough. Although this is the first formal report of red-water ciliate blooms for Lough Hyne and County Cork, it is not the first known occurrence; earlier spring red tides at the lough were assumed (probably in error) to be caused solely or primarily by dinoflagellates and/or loricate ciliates (tintinnids). [ABSTRACT FROM AUTHOR]

Examines the accuracy of the local-density or local-spin-density approximations when applied to transition metals. Data on the calculated cohesive strategies of the transition metals; Issues which confront those who wish to employ band theory in studies of magnetism.

Observations of the behavioural responses of near-shore marine scavengers to fish carrion were made at two depths (1–2 m, 16–18 m). Gobies and juvenile whelks were the most numerous scavengers, but appeared to consume little biomass. The first scavengers to appear at carrion (seconds/minutes) were swimming forms, later (minutes) joined by fast-moving, crawling portunid crabs. Large scavengers (crabs/starfish/catsharks) arrived after tens of minutes/hours. Scavengers were ‘direct feeders’ on the bait (crabs and some fish) or ‘indirect feeders’ (gobies and whelks) on scraps generated by direct feeders. Scavengers spent little time in aggression. While fish spent relatively low proportions of their time feeding (e.g.Lipophrys pholis: 2.2–15.8%), crabs fed almost continuously (e.g.Carcinus maenas: 97.8–99.3%) before leaving baits. Crab presence depressed fish feeding. Crabs were wasteful feeders that macerated the baits, generating scraps for indirect feeders and attracting more scavengers. Large scavengers consumed most bait. [ABSTRACT FROM AUTHOR]

Animals from cold environments are usually larger than animals from warm environments, which often produce clines in body size. Because variation in body size can lead to trade-offs between growth and reproduction, life-history traits should also vary across climatic gradients. To determine if life-history traits of wood frogs Rana sylvatica vary with climate, we examined female and male body length, clutch size, and ovum size from 37 locations across an unprecedented 32° of latitude. In conflict with recent research, body size, and ovum size decreased in cold climates and at higher latitudes. Clutch size did not vary with climate or latitude, but reproductive effort (clutch size:female size) did, suggesting selection for a life-history traits that favors maximizing propagule number over propagule size in cold climates. With accelerating climate change that will expose populations to novel environmental conditions, it is important to identify the limits of adaptation, which can be informed by greater understanding of variation in life-history traits. [ABSTRACT FROM AUTHOR]

Metacommunity ecology emphasizes the role of dispersal in linking local processes across space. Competition is one such local process that can be affected by dispersal. Dispersal can influence intraspecific trait variation, thereby affecting the strength of intraspecific competition and, consequently, the relative importance of intra- versus interspecific interactions. Prior research has shown that spring salamanders, G yrinophilus porphyriticus, self-organize within streams by a common trait (body condition) and that dispersal and gene flow along streams vary with slope. Building on this prior work, we tested how dispersal influences the strength of intraspecific competition via one of two spatial mechanisms: (1) spatial sorting of individuals by traits that affect competitive performance or (2) variation in gene flow resulting in evolutionary divergence of traits affecting competitive performance. To test these alternative mechanisms, we conducted a mesocosm experiment with spring salamanders from downstream and upstream sites of streams with low and high rates of dispersal and gene flow. Spatial patterns of intraspecific competitive performance differed significantly in the low- and high-dispersal streams. In the low-dispersal stream, downstream individuals were better intraspecific competitors than upstream individuals, whereas the opposite was true in the high-dispersal stream. These differences support the spatial sorting mechanism, reinforcing direct dispersal data showing that high-performance individuals are more likely to move upstream in the high-dispersal stream and to remain downstream in the low-dispersal stream. To our knowledge, this is the first time that spatial sorting has been explicitly identified as contributing to the strength of intraspecific interactions. Our study underscores the importance of integrating natural rates of dispersal into mechanistic experiments to understand spatial variability in the strength of intra- and interspecific species interactions. [ABSTRACT FROM AUTHOR]

This article describes a method of building RPD components into an effective design and indicates how the details of the design can be communicated clearly to the dental technician. [ABSTRACT FROM AUTHOR]

This article describes the benefits and risks of providing RPDs. It emphasises the importance of co-operation between the dental team and patient to ensure that the balance of this 'equation' is in the patient's favour. [ABSTRACT FROM AUTHOR]

We present the results of a blind exercise to test the recoverability of stellar rotation and differential rotation in Kepler light curves. The simulated light curves lasted 1000 d and included activity cycles, Sun-like butterfly patterns, differential rotation and spot evolution. The range of rotation periods, activity levels and spot lifetime were chosen to be representative of the Kepler data of solar-like stars. Of the 1000 simulated light curves, 770 were injected into actual quiescent Kepler light curves to simulate Kepler noise. The test also included five 1000-d segments of the Sun's total irradiance variations at different points in the Sun's activity cycle. Five teams took part in the blind exercise, plus two teams who participated after the content of the light curves had been released. The methods used included Lomb-Scargle periodograms and variants thereof, autocorrelation function and wavelet-based analyses, plus spot modelling to search for differential rotation. The results show that the 'overall' period is well recovered for stars exhibiting low and moderate activity levels. Most teams reported values within 10 per cent of the true value in 70 per cent of the cases. There was, however, little correlation between the reported and simulated values of the differential rotation shear, suggesting that differential rotation studies based on full-disc light curves alone need to be treated with caution, at least for solar-type stars. The simulated light curves and associated parameters are available online for the community to test their own methods. [ABSTRACT FROM AUTHOR]

Knowledge of phenological events in grapevines is essential for successful vineyard management. Conventional ground-observed phenological measurements are limited mainly due to their spatial coverage. However, satellite data provide access to global spatial coverage with the potential for high temporal resolution. The goal of this study was to evaluate the ability of vegetation indices based on remote sensing to estimate the growing season length of grapes in central Washington State. Several phenological metrics for vineyards located in the Columbia Valley region were derived from the satellite time series of the Moderate Resolution Imaging Spectroradiometer (MODIS) using the normalized difference vegetation index (NDVI). The methodology included exponential smoothing and a moving average to compute both the onset of greenness and the end of greenness. The MODIS NDVI values were evaluated with aerial NDVI images of the same vineyard from August 2011. The average bias was -0.08, the average root mean squared error (RMSE) was 0.16, and the coefficient of determination (R²) was 0.5 (p = 0.06). The results revealed an average growing season duration of 216 days for grapevines in this region for a period of five years. The average starting date of the growing season was April 2, and the computed end of the growing season was November 4. The highest NDVI value was 0.55, which coincided with July 12. On average, the lowest NDVI value was 0.3, and the average range of NDVI was 0.25. The preliminary results of this study showed that MODIS NDVI can be used to monitor vineyard vegetation dynamics in the Columbia Valley and has potential to be applied to other grape-growing regions in the U.S. and across the globe. [ABSTRACT FROM AUTHOR]

The effects of OATP1B1, OAT3, and MRP2 on the pharmacokinetics of eluxadoline, an oral, locally active, opioid receptor agonist/antagonist being developed for treatment of IBS-d were assessed in vivo. Coadministration of a single 200 mg dose of eluxadoline with cyclosporine, and probenecid increased eluxadoline systemic exposure [AUC(0-inf)] by 4.4- and 1.4-fold, respectively, whereas peak exposure (Cmax) increased 6.2-fold and 1.3-fold, respectively. Cyclosporine had little effect on renal clearance (CLren) of eluxadoline whereas probenecid reduced CLren by nearly 50%. These study results suggested that sinusoidal OATP1B1-mediated hepatic uptake of eluxadoline (during first-pass and systemic extraction) plays a major role in its absorption and disposition, whereas OAT3-mediated basolateral uptake in the proximal renal tubules and MRP2-mediated canalicular and renal tubular apical efflux play only minor roles in its overall disposition. All treatments were safe and well tolerated. [ABSTRACT FROM AUTHOR]

Cylindrical algebraic decompositions (CADs) are a key tool in real algebraic geometry, used primarily for eliminating quantifiers over the reals and studying semi-algebraic sets. In this paper we introduce cylindrical algebraic sub-decompositions (sub-CADs), which are subsets of CADs containing all the information needed to specify a solution for a given problem. We define two new types of sub-CAD: variety sub-CADs which are those cells in a CAD lying on a designated variety; and layered sub-CADs which have only those cells of dimension higher than a specified value. We present algorithms to produce these and describe how the two approaches may be combined with each other and the recent theory of truth-table invariant CAD. We give a complexity analysis showing that these techniques can offer substantial theoretical savings, which is supported by experimentation using an implementation in Maple. [ABSTRACT FROM AUTHOR]

The article focuses on a study which estimated the total population of Eurasian badgers, Meles meles L., in the Republic of Ireland. Specific study areas include Cork, Donegal, Kilnenny and Monaghan, al representing a range of agricultural habitat types. Intensive protective badger removal was conducted in the areas with the goal of obtaining a low badger density. Data showed that a total of 1,099 badgers were removed from the areas between 1997 and 1999, with 73.2% of badgers were caught at main setts and 26.8% at outlier setts. The study confirmed that badgers are widespread in agricultural habitats across the country.

The article presents a study on the effect of barriers, such as external buffers and rivers, on the immigration of badger Meles meles during the Four Area project in Ireland. It is noted that the there was proactive culling of badgers at the location of the barriers. The researchers assume that all the badgers caught in the space of the removal areas came across the barriers and that all the badgers caught were immigrants. Using chi-square tests, the researchers claim that sea and external buffers are the most effective. They also emphasize the importance of understanding the effectiveness of barriers to the efficiency of badger management options.

We have developed a Scalable Linear Augmented Slater-Type Orbital (LASTO) method for electronic-structure calculations on free-standing atomic clusters. As with other linear methods we solve the Schrödinger equation using a mixed basis set consisting of numerical functions inside atom-centered spheres and matched onto tail functions outside. The tail functions are Slater-type orbitals, which are localized, exponentially decaying functions. To solve the Poisson equation between spheres, we use a finite difference method replacing the rapidly varying charge density inside the spheres with a smoothed density with the same multipole moments. We use multigrid techniques on the mesh, which yields the Coulomb potential on the spheres and in turn defines the potential inside via a Dirichlet problem. To solve the linear eigen-problem, we use ScaLAPACK, a well-developed package to solve large eigensystems with dense matrices. We have tested the method on small clusters of palladium. © 2008 Wiley Periodicals, Inc. J Comput Chem, 2009 [ABSTRACT FROM AUTHOR]

Chemical cues can assist intraspecific communication associated with sexual behavior, territoriality, and home-site philopatry. We tested experimentally the influence of chemical cues on the behavior of male Common Musk Turtles (Sternotherus odoratus). In laboratory-controlled choice boxes, we video recorded the location of turtles moving between two water tanks separated by a raised divider. Water was scented by no turtles, the test turtle, another male, or a female. Based on two-hour trials, we considered turtles that spent > 55% of the time in one water tank as having demonstrated a scent preference. From at least 10 replicates of each of six different treatment combinations, males significantly chose tanks with the scent of a female versus tanks with clean water, the scent of self, or the scent of another male. We propose that the smell produced by a female turtle includes an intraspecific chemical cue that helps males search for potential mates. [ABSTRACT FROM AUTHOR]

Soft X-ray absorption spectroscopy (XAS), using fluorescence yield, was used to study the boron K near edge in MgB2 superconductor. The sample consists of MgB2 crystallites randomly oriented in a magnesium matrix. Abrasion of the sample surface in vacuum provides a surface relatively free of boron-containing impurities. The intrinsic boron K near edge spectrum of the sample at a temperature of 295 K is identified. This spectrum is then compared in detail with a spectrum calculated using the full potential linearized augmented plane wave method. Features predicted by the theory appear near the expected energies, with qualitative agreement regarding shape and intensity. [ABSTRACT FROM AUTHOR]

Ingestion of bivalve larvae by Mytilus edulis was investigated. Laboratory experiments revealed that ~ 90% of bivalve larvae offered to mussels was ingested and apparently fully digested. The shell of the bivalve larvae offered no protection against digestive processes, resulting in high larval mortality once inside the stomach. Stomach content analysis (September 2001–January 2003) showed that bivalve larvae were ingested by farmed mussels year-round, with the exception of March 2002. Numbers of ingested larvae were highest in October 2001 and May 2002, which coincides with known spawning times of farmed mussels in Ireland. Mussels ingested a large size-range of bivalve larvae, suggesting that all stages of the bivalve life cycle are vulnerable to predation. It is suggested that adult bivalves routinely filter larvae from the surrounding water and that, given the high biomass of mussels present in mussel farms, filtration by adult bivalves significantly reduces numbers of bivalve larvae in nearby waters. [ABSTRACT FROM AUTHOR]

The article explores the use of a machine with novel architecture designed for quantum chromodynamics (QCD). The quantum chromodynamics on a chip (QCDOC) architecture has two attractive and unusual features, a very high degree of communication parallelism and a very low latency. The result appears to be a design with highly scalable parallel performance. The QCDOC high per formance network allows a very high level of parallelism and very fast solutions, for a number of basic algorithms of wide interest. Because of the high level of parallelism, small problem sizes per processor are feasible, with the result that the entire problem fits in the on-chip, L2 cache, memory. Authors expect that the performance as a fraction of peak speed will be comparable to that of a vector machine. The machine is scalable by design, and is recognized to be very cost effective per teraflop of sustained performance. The machine should excel especially for problems for which large numbers of timesteps are the figure of merit.

Patterns of zooplankton vertical movement are often difficult to interpret because of multiple, complex and confounding environmental factors. Behavioural adaptations to these environmental variables are compared within and between the holo- and meroplankton constituents of a community. We used a nested design to analyse patterns at several scales in time; (semi-diel, diel, spring-neap tidal cycle and season) and two in space; (depth and site). To reduce complexity and aid interpretation we studied a semi-isolated community in a semi-enclosed, seasonally stratified sea lough (Lough Hyne Marine Nature Reserve, Ireland). In this, the main environmental gradient was water flow rate (or water residence time) caused by tidal currents. Vertical profiles of abundance showed that populations of the most abundant species of holo- and meroplankton in the lough have considerable behavioural plasticity, enabling them to switch between sedentary and migratory behaviour and patterns of migration. Some species migrate vertically in synchrony with diel cycles and others in response to semi-diel tidal currents; a few do both, but the majority did neither. It is suggested that water column structure and hydrographic discontinuities caused by flow rate and pycnocline dynamics are responsible for the variable patterns of vertical migration and distribution. [ABSTRACT FROM AUTHOR]

Oxygen levels were monitored within the mantle cavities of three barnacle species (Chthamalus stellatus, Semibalanus balanoides, Elminius modestus), using optode microsensors. Conditions were always hypoxic, even when barnacles were actively using the prosoma and cirri to pump aerated seawater into the mantle cavity. Mantle fluid oxygen concentrations were extremely variable; behaviour and oxygen concentrations were not closely coupled. Ventilation of the mantle cavity depended partially on external water flow, with higher and more stable mantle fluid oxygen concentrations being sustained when the water around barnacles was agitated. During emersion, barnacles initially pumped seawater between the mantle cavity and the cone above the opercular plates to achieve ventilation. As water was lost it was replaced by air bubbles, eventually resulting in an air-filled mantle cavity. In S. balanoides and E. modestus, once the mantle cavity was filled with air, the barnacle usually used up the oxygen within the bubble within 2–3 h and did not regain oxic conditions until the barnacle was reimmersed in seawater. In C. stellatus, the air bubble was repeatedly refreshed for many hours by pneumostome formation. In response to low environmental salinity, all three species closed the opercular plates firmly and rapidly used up oxygen within the mantle fluid. [ABSTRACT FROM AUTHOR]