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Maternal effects can be adaptive and because of their intrinsic time delays may have important effects on population dynamics. In vertebrates, and increasingly invertebrates, it is well established that offspring defence is in part determined by maternal parasite exposure. It has also been suggested that there may be indirect maternal effects on immunity mediated by other components of the maternal environment, including density and resource availability. Here, we examine the effect maternal resource availability has on the immunity of offspring in an insect—virus system. We use five different maternal resource levels and examine immunity in the offspring both directly, by challenge with a virus, and by measuring a major component of the immune system, across three offspring environments. Both the direct infection assay and the measure of immunocompetence show clearly that offspring from mothers in poor environments are more resistant to parasites. This may result from life-history optimization of mothers in poor environments, or because the poor environment acts as a cue for higher disease risk in the next generation. This emphasizes the importance of maternal effects on disease resistance, mediated through indirect environmental factors that will have important implications to both the ecological and evolutionary dynamics of host–parasite interactions. [ABSTRACT FROM AUTHOR]

Cross-linked polymer films were investigated as new gate dielectric materials for low-voltage thin-film transistors. Poly(4-vinylphenol) (PVP) was cross-linked through esterification reactions with commercially available bifunctional anhydrides, acyl chlorides, and carboxylic acids. The polymer dielectric films were evaluated based on surface morphology, capacitance, leakage current, and their compatibility with organic semiconductors. Thin insulating PVP films cross-linked with dianhydrides yielded a capacitance as high as 400 nF/cm2with leakage currents below 10−8A/cm2. Organic thin-film transistors (OTFTs) fabricated on these gate dielectric layers exhibited charge carrier mobilities as high as 3 cm2/(V s) for p-channel pentacene on octadecyltriethoxylsilane (OTS)-modified PVP and 0.045 cm2/(V s) for n-channel perfluorinated copper phthalocyanine (FCuPc). [ABSTRACT FROM AUTHOR]

Background The aim was to critically appraise and synthesize the literature relating to set-shifting ability in eating disorders. PsycINFO, Medline, and Web of Science databases were searched to December 2005. Hand searching of eating-disorder journals and relevant reference sections was also undertaken.Method The 15 selected studies contained both eating disorder and healthy control groups, and employed at least one of the following six neuropsychological measures of set-shifting ability; Trail Making Test (TMT), Wisconsin Card Sort Test (WCST), Brixton task, Haptic Illusion, CatBat task, or the set-shifting subset of the Cambridge Neuropsychological Test Automated Battery (CANTAB). The outcome variable was performance on the set-shifting aspect of the task. Pooled standardized mean differences (effect sizes) were calculated.Results TMT, WCST, CatBat and Haptic tasks had sufficient sample sizes for meta-analysis. These four tasks yielded acceptable pooled standardized effect sizes (0·36; TMT −1·05; Haptic) with moderate variation within studies (as measured by confidence intervals). The Brixton task showed a small pooled mean difference, and displayed more variation between sample results. The effect size for CANTAB set shifting was 0·17.Conclusion Problems in set shifting as measured by a variety of neuropsychological tasks are present in people with eating disorders. [ABSTRACT FROM AUTHOR]

Objectives. The practice of musculoskeletal ultrasonography (MSKUS) by UK rheumatologists remains limited, despite their reported enthusiasm. This study aimed to investigate factors that may encourage or limit future dissemination of rheumatologist-performed MSKUS and provide insights into perceived clinical importance and learning motivation relating to published recommendations by MSKUS experts.Methods. A written questionnaire study was conducted, involving 48 rheumatologists. Questions included the potential role of self-performed MSKUS, skills that they would be willing to learn and factors that may encourage or limit learning and practice. Competency recommendations proposed by imaging experts (142 skills in 7 anatomical areas) were reviewed, and quantitative and qualitative data collected regarding ‘value to their practice’ and ‘learning motivation’.Results. Eighty-nine percent wished to learn MSKUS. Factors influencing learning and practice included time to achieve competency; relative-added clinical value of MSKUS examination; limited training infrastructure; access to existing imaging service; equipment funding. Skills offering greatest clinical utility were inflammatory arthritis assessment and guided procedures; least useful were evaluation of ligament/muscle lesions and soft tissue masses. There was a close correlation between clinical utility, learning motivation and competency standard.Conclusions. A trade-off between added clinical value and time to achieve competency is the major factor influencing practice and training in MSKUS. Most rheumatologists report limited time to devote to training and therefore need to prioritize areas of importance for dedicated learning. Educational programmes need to be highly focused and relevant to clinical and job–plan requirements in order to encourage future dissemination of MSKUS practice by rheumatologists. [ABSTRACT FROM AUTHOR]

Objectives. Musculoskeletal ultrasonography (MSKUS) has been described by some rheumatologists as the ‘stethoscope of the joint’. Such enthusiasm is supported by evidence confirming validity and clinical utility in evaluation of musculoskeletal diseases. But if rheumatologist-performed MSKUS is to emulate the impact of cardiologist-performed echocardiography, a number of educational challenges need be addressed. Evaluation of current training reveals the absence of a unified educational structure, ad hoc teaching and assessment and published data are insufficient to make practice and training recommendations specific to rheumatology.Methods. Informed by developments in adult-learning theory, we have utilized a competency-based approach to develop an educational programme for rheumatologist ultrasonographers. Fundamental to this process has been accurate functional analysis of the role of the rheumatologist ultrasonographer and precise translation of these data into educational outcomes. This involved a thorough, transparent, iterative, curriculum-defining approach, employing quantitative and qualitative research techniques including interview, questionnaire, Delphi and standard setting methodologies. All relevant stakeholders were engaged, including international US experts and clinical rheumatologists.Results. Outcomes include clarification of the role of a rheumatologist ultrasonographer; definition of appropriate knowledge and skills; establishment of competency standards; a balanced, clearly defined, clinically relevant educational outcome blueprint. Teaching and assessment approaches have been piloted as part of an accessible modular curriculum strategy. Thorough validation and evaluation confirms effectiveness, efficiency and suitability.Conclusions. A comprehensive evidence-based, expert consensus-defined educational framework is proposed that provides a template for teaching and learning and standards for competency assessment. This should facilitate common principles of training, uniform professional practice and a justifiable governance structure. [ABSTRACT FROM AUTHOR]

PSR J2129−0429 is a 7.62 ms eclipsing millisecond pulsar (MSP) with a non-degenerate binary companion star that is likely in an early stage of the recycling process. It has one of the largest companion masses of a so-called “redback” (0.4 M⊙) and has an unusually high surface magnetic field (1.6 × 109 G) for an MSP. We present here an X-ray and optical study of PSR J2129−0429 using new NuSTAR and LCOGT data of the system in addition to archival Swift and XMM-Newton data. Its X-ray light curve shows strong orbital variation from the intra-binary shock, about five times greater than is typical for other systems, and is clearly and persistently double-peaked. Its X-ray spectrum has a very hard power-law component (Γ = 1.1–1.2) which extends to ∼40 keV and exhibits an efficiency of up to a few percent in the X-ray band. The X-ray spectrum at the second peak of the light curve exhibits strong variability, while the spectrum of the first peak remains constant across observations. The hardness of the spectrum is suggestive of driven magnetic reconnection occurring at the shock. In addition, we observe the companion to be currently optically brightening after a multi-year period where it was dimming. The changes in color suggest that it has been continually cooling, implying that the companion is currently expanding. [ABSTRACT FROM AUTHOR]

In 1982, flight tests were conducted on a modified OH-6A helicopter that incorporated an active higher harmonic control system to reduce vibratory loads on the rotor system. While reducing vibrations up to 90%, open-loop higher harmonic control data showed significant reductions in the main rotor shaft torque and engine power indicating that higher harmonic control may be also providing performance improvements. In this study, unsteady, rotary-wing, potential flow theory for a thin, oscillating airfoil is used to explain the mechanism behind the performance improvements seen on the OH-6A. Equations for the 2-D, unsteady, rotary-wing aerodynamic forces and moments with a finite number of wakes, or shed layers of vorticity, beneath the rotor are developed and applied specifically to the pitch and flap oscillations seen in the hover flight-test data. A modified finite-wake lift deficiency function is developed for this finite-wake theory that is analogous to the classical Theodorsen and Loewy lift deficiency functions, and is used in used to calculate the horizontal time-averaged propulsive force (negative drag) derived by Garrick to show that unsteady aerodynamics can provide the order of magnitude effects necessary to quantify the performance improvements seen on the OH-6A. [ABSTRACT FROM AUTHOR]

We present results of a 400 ks Chandra observation of the young shell supernova remnant (SNR) G11.2−0.3, containing a pulsar and pulsar-wind nebula (PWN). We measure a mean expansion rate for the shell since 2000 of 0.0277 ± 0.0018% yr−1, implying an age between 1400 and 2400 yr, and making G11.2−0.3 one of the youngest core-collapse SNRs in the Galaxy. However, we find very high absorption (AV ∼ 16m ± 2m), confirming near-IR determinations and ruling out a claimed association with the possible historical SN of 386 CE. The PWN shows strong jets and a faint torus within a larger, more diffuse region of radio emission and nonthermal X-rays. Central soft thermal X-ray emission is anticorrelated with the PWN; that, and more detailed morphological evidence, indicates that the reverse shock has already reheated all ejecta and compressed the PWN. The pulsar characteristic energy-loss timescale is well in excess of the remnant age, and we suggest that the bright jets have been produced since the recompression. The relatively pronounced shell and diffuse hard X-ray emission in the interior, enhanced at the inner edge of the shell, indicate that the immediate circumstellar medium into which G11.2−0.3 is expanding was quite anisotropic. We propose a possible origin for G11.2−0.3 in a stripped-envelope progenitor that had lost almost all its envelope mass, in an anisotropic wind or due to binary interaction, leaving a compact core whose fast winds swept previously lost mass into a dense irregular shell, and which exploded as a SN cIIb or Ibc. [ABSTRACT FROM AUTHOR]

Many biodiversity hotspots are located in montane regions, especially in the tropics. A possible explanation for this pattern is that the narrow thermal tolerances of tropical species and greater climatic stratification of tropical mountains create more opportunities for climate-associated parapatric or allopatric speciation in the tropics relative to the temperate zone. However, it is unclear whether a general relationship exists among latitude, climatic zonation and the ecology of speciation. Recent taxon-specific studies obtained different results regarding the role of climate in speciation in tropical versus temperate areas. Here, we quantify overlap in the climatic distributions of 93 pairs of sister species of mammals, birds, amphibians and reptiles restricted to either the New World tropics or to the Northern temperate zone. We show that elevational ranges of tropical- and temperate-zone species do not differ from one another, yet the temperature range experienced by species in the temperate zone is greater than for those in the tropics. Moreover, tropical sister species tend to exhibit greater similarity in their climatic distributions than temperate sister species. This pattern suggests that evolutionary conservatism in the thermal niches of tropical taxa, coupled with the greater thermal zonation of tropical mountains, may result in increased opportunities for allopatric isolation, speciation and the accumulation of species in tropical montane regions. Our study exemplifies the power of combining phylogenetic and spatial datasets of global climatic variation to explore evolutionary (rather than purely ecological) explanations for the high biodiversity of tropical montane regions. [ABSTRACT FROM AUTHOR]

The water-soluble fullerene derivative γ-cyclodextrin bicapped C60[(γ-CyD)2/C60, CDF0] has several clinical applications, including use as a drug carrier to bypass the blood ocular barriers or a photosensitizer to treat tumors in photodynamic therapy. We have assessed the potential ocular toxicity of (γ-CyD)2/C60and its aggregated derivatives induced by UVA and visible light in vitro in human lens epithelial cells (HLE B-3). Cell viability using the MTS assay demonstrated that 2 μM (γ-CyD)2/C60was highly phototoxic to HLE B-3 cells with UVA irradiation, while no effect was observed in the presence of visible light or when maintained in the dark. In contrast, the aggregated derivative (CDF150) showed neither cytotoxicity nor any phototoxic effect even at 30 μM with either UVA or visible light irradiation. In lens cells treated with (γ-CyD)2/C60, phototoxicity was manifested as apoptosis. Singlet oxygen production measurement using the EPR/TEMP trapping technique determined that (γ-CyD)2/C60(CDF0) efficiently produced singlet oxygen. The rate of singlet oxygen production decreased with increased aggregation, with no production by the fully aggregated sample formed after 150 min of heating (CDF150). UVA irradiation of HLE B-3 in the presence of (γ-CyD)2/C60resulted in a significant rise in intracellular protein-derived peroxides. The singlet oxygen quenchers sodium azide and histidine each significantly protected lens cells against (γ-CyD)2/C60photodamage, but lutein and Trolox (vitamin E) did not. Clearly, singlet oxygen is an important intermediate in the phototoxicity of monomeric (γ-CyD)2/fullerene. Our results also demonstrate that UVA-blocking sunglasses can limit the ocular phototoxicity of this nanomaterial, while nontoxic endogenous antioxidants like lutein or Trolox cannot provide adequate protection. [ABSTRACT FROM AUTHOR]

This study presents measurements of the transport of quasiparticle excitations in the B phase of superfluid 3He at temperatures below 0.2Tc. We find that creating and then removing a layer of A-phase superfluid leads to a measurable increase in the thermal impedance of the background B phase. This increase must be due to the survival of defects created as the AB and BA interfaces on either side of the A-phase layer annihilate. We speculate that a new type of defect may have been formed. The highly ordered A–B interface may be a good analogy for branes discussed in current cosmology. If so, these experiments may provide insight into how the annihilation of branes can lead to the formation of topological defects such as cosmic strings. [ABSTRACT FROM AUTHOR]

Air-stable p-type semiconducting oligofluorene–thiophene derivatives were vacuum-deposited on octadecyltriethoxysilane-treated SiO 2/Si substrates. Effects of end-substituents and substrate deposition temperature ( TD) on molecular orientation, crystalline morphologies, and structures in these thin films were investigated by two-dimensional grazing incidence X-ray diffraction and atomic force microscopy, and those results were correlated with charge mobility in top-contacted devices. Crystalline morphologies of the first monolayer thin film in direct contact with the dielectric surface, influenced by TDs (25, 90, and 140 °C) and end-substituted groups (hydrogen, hexyl, and dodecyl), could be categorized as dendrite, compact disk, and single-crystal-like layered grains. The results of grazing incidence X-ray diffraction strongly support that molecular orientation in the films can be finely tuned through controlling substrate, TD, and molecular architecture, resulting in high air stability and field-effect mobility in a top-contacted electrode of organic thin film transistors. [ABSTRACT FROM AUTHOR]

The Green Bank North Celestial Cap (GBNCC) pulsar survey will cover the entire northern sky (δ > −40°) at 350 MHz, and is one of the most uniform and sensitive all-sky pulsar surveys to date. We have created a pipeline to reanalyze GBNCC survey data to take a 350 MHz census of all pulsars detected by the survey, regardless of their discovery survey. Of the 1413 pulsars in the survey region, we were able to recover 670. For these we present measured signal-to-noise ratios (S/N), flux densities, pulse widths, profiles, and where appropriate, refined measurements of dispersion measures (DMs) (656 out of 670) and new or improved spectral indices (339 out of 670 total, 47 new, 292 improved). We also measure the period-pulse width relation at 350 MHz to scale as . Detection scans for several hundred sources were reanalyzed in order to inspect pulsars’ single pulse behavior and 223 were found to exhibit evidence of nulling. With a detailed analysis of measured and expected S/N values and the evolving radio frequency interference environment at 350 MHz, we assess the GBNCC survey’s sensitivity as a function of spin period, DM, and sky position. We find the sky-averaged limiting flux density of the survey to be 0.74 mJy. Combining this analysis with PsrPopPy pulsar population simulations, we predict 60/5 nonrecycled/MSP discoveries in the survey’s remaining 21,000 pointings, and we begin to place constraints on population model parameters. [ABSTRACT FROM AUTHOR]

We provide timing solutions for 45 radio pulsars discovered by the Robert C. Byrd Green Bank Telescope. These pulsars were found in the Green Bank North Celestial Cap pulsar survey, an all-GBT-sky survey being carried out at a frequency of . We include pulsar timing data from the Green Bank Telescope and Low Frequency Array. Our sample includes five fully recycled millisecond pulsars (MSPs, three of which are in a binary system), a new relativistic double neutron star system, an intermediate-mass binary pulsar, a mode-changing pulsar, a 138 ms pulsar with a very low magnetic field, and several nulling pulsars. We have measured two post-Keplerian parameters and thus the masses of both objects in the double neutron star system. We also report a tentative companion mass measurement via Shapiro delay in a binary MSP. Two of the MSPs can be timed with high precision and have been included in pulsar timing arrays being used to search for low-frequency gravitational waves, while a third MSP is a member of the black widow class of binaries. Proper motion is measurable in five pulsars, and we provide an estimate of their space velocity. We report on an optical counterpart to a new black widow system and provide constraints on the optical counterparts to other binary MSPs. We also present a preliminary analysis of nulling pulsars in our sample. These results demonstrate the scientific return of long timing campaigns on pulsars of all types. [ABSTRACT FROM AUTHOR]

The origin of the high-frequency radio emission detected from several magnetars is poorly understood. In this paper, we report the properties of SGR J1745−29 measured using Jansky Very Large Array (JVLA) and Robert C. Byrd Green Bank Telescope (GBT) observations between 2013 October 26 and 2014 May 31. Our analysis of a Q-band (45 GHz) GBT observation on 2014 April 10 resulted in the earliest detection of pulsed radio emission at high frequencies (); we found that the average pulse has a singly peaked profile with width (∼2% of the pulse period) and an average pulsed flux density of ∼100 mJy. We also detected very bright, short single pulses during ∼70% of this neutron star’s rotations, and the peak flux densities of these bright pulses follow the same log-normal distribution as measured at 8.5 GHz. Additionally, our analysis of contemporaneous JVLA observations suggest that its 41/44 GHz flux density varied between ∼1–4 mJy during this period, with a change observed on ∼20 minute timescales during a JVLA observation on 2014 May 10. Such a drastic change over short timescales is inconsistent with the radio emission resulting from a shock powered by the magnetar’s supersonic motion through the surrounding medium, but consistent with pulsed emission generated in its magnetosphere. [ABSTRACT FROM AUTHOR]

We report on a search for fast radio bursts (FRBs) with the Green Bank Northern Celestial Cap (GBNCC) Pulsar Survey at 350 MHz. Pointings amounting to a total on-sky time of 61 days were searched to a dispersion measure (DM) of 3000 pc cm−3, while the rest (23 days; 29% of the total time) were searched to a DM of 500 pc cm−3. No FRBs were detected in the pointings observed through 2016 May. We estimate a 95% confidence upper limit on the FRB rate of FRBs sky−1 day−1 above a peak flux density of 0.63 Jy at 350 MHz for an intrinsic pulse width of 5 ms. We place constraints on the spectral index α by running simulations for different astrophysical scenarios and cumulative flux density distributions. The nondetection with GBNCC is consistent with the 1.4 GHz rate reported for the Parkes surveys for α > +0.35 in the absence of scattering and free–free absorption and α > −0.3 in the presence of scattering, for a Euclidean flux distribution. The constraints imply that FRBs exhibit either a flat spectrum or a spectral turnover at frequencies above 400 MHz. These constraints also allow estimation of the number of bursts that can be detected with current and upcoming surveys. We predict that CHIME may detect anywhere from several to ∼50 FRBs per day (depending on model assumptions), making it well suited for interesting constraints on spectral index, the log N–log S slope, and pulse profile evolution across its bandwidth (400–800 MHz). [ABSTRACT FROM AUTHOR]

PSR J2129−0429 is a “redback” eclipsing millisecond pulsar binary with an unusually long 15.2 hr orbit. It was discovered by the Green Bank Telescope in a targeted search of unidentified Fermi gamma-ray sources. The pulsar companion is optically bright (mean mR = 16.6 mag), allowing us to construct the longest baseline photometric data set available for such a system. We present 10 years of archival and new photometry of the companion from the Lincoln Near-Earth Asteroid Research Survey, the Catalina Real-time Transient Survey, the Palomar Transient Factory, the Palomar 60 inch, and the Las Cumbres Observatory Global Telescope. Radial velocity spectroscopy using the Double-Beam Spectrograph on the Palomar 200 inch indicates that the pulsar is massive: 1.74 ± 0.18 . The G-type pulsar companion has mass 0.44 ± 0.04 , one of the heaviest known redback companions. It is currently 95 ± 1% Roche-lobe filling and only mildly irradiated by the pulsar. We identify a clear 13.1 mmag yr−1 secular decline in the mean magnitude of the companion as well as smaller-scale variations in the optical light curve shape. This behavior may indicate that the companion is cooling. Binary evolution calculations indicate that PSR J2129−0429 has an orbital period almost exactly at the bifurcation period between systems that converge into tighter orbits as black widows and redbacks and those that diverge into wider pulsar–white dwarf binaries. Its eventual fate may depend on whether it undergoes future episodes of mass transfer and increased irradiation. [ABSTRACT FROM AUTHOR]

We have discovered 21 Rotating Radio Transients (RRATs) in data from the Green Bank Telescope (GBT) 350 MHz Drift-scan and the Green Bank North Celestial Cap pulsar surveys using a new candidate sifting algorithm. RRATs are pulsars with sporadic emission that are detected through their bright single pulses rather than Fourier domain searches. We have developed RRATtrap, a single-pulse sifting algorithm that can be integrated into pulsar survey data analysis pipelines in order to find RRATs and Fast Radio Bursts. We have conducted follow-up observations of our newly discovered sources at several radio frequencies using the GBT and Low Frequency Array, yielding improved positions and measurements of their periods, dispersion measures (DMs), and burst rates, as well as phase-coherent timing solutions for four of them. The new RRATs have DMs ranging from 15 to 97 , periods of 240 ms to 3.4 s, and estimated burst rates of 20 to 400 pulses hr−1 at 350 MHz. We use this new sample of RRATs to perform statistical comparisons between RRATs and canonical pulsars in order to shed light on the relationship between the two populations. We find that the DM and spatial distributions of the RRATs agree with those of the pulsars found in the same survey. We find evidence that slower pulsars (i.e., ms) are preferentially more likely to emit bright single pulses than are faster pulsars ( ms), although this conclusion is tentative. Our results are consistent with the proposed link between RRATs, transient pulsars, and canonical pulsars as sources in various parts of the pulse activity spectrum. [ABSTRACT FROM AUTHOR]