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The technology of manufacturing aluminum alloy workpieces using additive friction stir deposition (AFS‐D) has been thoroughly investigated. The ambiguous influence of deformation processing modes on the material density was found. Examination of the microstructure in the central zone of the specimens reveals the absence of microdefects typically associated with workpieces obtained through casting or powder metallurgy methods. It has been observed that the distribution of microhardness is significantly affected by the direction of specimen construction, with approximately a 20% difference in values between the periphery and the central part of the specimen. Specimens produced using the AFS‐D method exhibit a homogeneous microstructure characteristic of deformable aluminum alloys. Notably, a uniform distribution of intermetallides on the specimen surface has been identified. This outcome is likely a result of the alloy undergoing recrystallization during the severe plastic deformation process, leading to the formation of an ultradisperse structure. It is important to emphasize that the selection of technological parameters for AFS‐D should consider not only the magnitude of pressure and deformation but also the deformation speed. [ABSTRACT FROM AUTHOR]

Background: Breath‐holding (BH) for cine balanced steady state free precession (bSSFP) imaging is challenging for patients with impaired BH capacity. Deep learning‐based reconstruction (DLR) of undersampled k‐space promises to shorten BHs while preserving image quality and accuracy of ventricular assessment. Purpose: To perform a systematic evaluation of DLR of cine bSSFP images from undersampled k‐space over a range of acceleration factors. Study Type: Retrospective. Subjects: Fifteen pectus excavatum patients (mean age 16.8 ± 5.4 years, 20% female) with normal cardiac anatomy and function and 12‐second BH capability. Field Strength/Sequence: 1.5‐T, cine bSSFP. Assessment: Retrospective DLR was conducted by applying compressed sensitivity encoding (C‐SENSE) acceleration to systematically undersample fully sampled k‐space cine bSSFP acquisition data over an acceleration/undersampling factor (R) considering a range of 2 to 8. Quality imperceptibility (QI) measures, including structural similarity index measure, were calculated using images reconstructed from fully sampled k‐space as a reference. Image quality, including contrast and edge definition, was evaluated for diagnostic adequacy by three readers with varying levels of experience in cardiac MRI (>4 years, >18 years, and 1 year). Automated DL‐based biventricular segmentation was performed commercially available software by cardiac radiologists with more than 4 years of experience. Statistical Tests: Tukey box plots, linear mixed effects model, analysis of variance (ANOVA), weighted kappa, Kruskal–Wallis test, and Wilcoxon signed‐rank test were employed as appropriate. A P‐value <0.05 was considered statistically significant. Results: There was a significant decrease in the QI values and edge definition scores as R increased. Diagnostically adequate image quality was observed up to R = 5. The effect of R on all biventricular volumetric indices was non‐significant (P = 0.447). Data Conclusion: The biventricular volumetric indices obtained from the reconstruction of fully sampled cine bSSFP acquisitions and DLR of the same k‐space data undersampled by C‐SENSE up to R = 5 may be comparable. Evidence Level: 3 Technical Efficacy: Stage 1 [ABSTRACT FROM AUTHOR]

Imaging energy filters in photoelectron microscopes and momentum microscopes use spherical fields with deflection angles of 90°, 180° and even 2 × 180°. These instruments are optimized for high energy resolution, and exhibit image aberrations when operated in high transmission mode at medium energy resolution. Here, a new approach is presented for bandpass‐filtered imaging in real or reciprocal space using an electrostatic dodecapole with an asymmetric electrode array. In addition to energy‐dispersive beam deflection, this multipole allows aberration correction up to the third order. Here, its use is described as a bandpass prefilter in a time‐of‐flight momentum microscope at the hard X‐ray beamline P22 of PETRA III. The entire instrument is housed in a straight vacuum tube because the deflection angle is only 4° and the beam displacement in the filter is only ∼8 mm. The multipole is framed by transfer lenses in the entrance and exit branches. Two sets of 16 different‐sized entrance and exit apertures on piezomotor‐driven mounts allow selection of the desired bandpass. For pass energies between 100 and 1400 eV and slit widths between 0.5 and 4 mm, the transmitted kinetic energy intervals are between 10 eV and a few hundred electronvolts (full width at half‐maximum). The filter eliminates all higher or lower energy signals outside the selected bandpass, significantly improving the signal‐to‐background ratio in the time‐of‐flight analyzer. [ABSTRACT FROM AUTHOR]

The asymmetric oxirane ring‐opening reaction leading to the formation of regioisomeric chlorohydrin esters was studied in the reaction series "acetic acid–epichlorohydrin–tetrahydrofuran (nitrobenzene)–trialkylamine" by kinetic methods and FT‐IR spectroscopy. The effect of solvent polarity and the structure of tertiary amines on the regioselectivity and reaction rate were studied. Tertiary amines with comparable basicity but different nucleophilicity and spatial structure were chosen as catalysts. It was shown that in solvents of different polarity, the components of the initial reaction system are present both as hydrogen‐bonded complexes and as individual substances. The reaction orders with respect to acid and amine in solvents of different polarity were established. Correlations between the reaction rate and the parameters of nucleophilicity and structure of amines as well as the polarity of the solvent were established. The regioselectivity of the reaction was studied by 1H NMR spectroscopy using the ratio of regioisomeric reaction products. It was shown that the regioselectivity and rate of catalytic acetolysis of epichlorohydrin are effectively controlled by the structure of tertiary amines and the polarity of the solvent. The scheme of reaction regio‐flows was detailed. [ABSTRACT FROM AUTHOR]

Cells secrete extracellular vesicles (EVs) and non‐vesicular extracellular (nano)particles (NVEPs or ENPs) that may play a role in intercellular communication. Tumor‐derived EVs have been proposed to induce immune priming of antigen presenting cells or to be immuno‐suppressive agents. We suspect that such disparate functions are due to variable compositions in EV subtypes and ENPs. We aimed to characterize the array of secreted EVs and ENPs of murine tumor cell lines. Unexpectedly, we identified virus‐like particles (VLPs) from endogenous murine leukemia virus in preparations of EVs produced by many tumor cells. We established a protocol to separate small EVs from VLPs and ENPs. We compared their protein composition and analyzed their functional interaction with target dendritic cells. ENPs were poorly captured and did not affect dendritic cells. Small EVs specifically induced dendritic cell death. A mixed large/dense EV/VLP preparation was most efficient to induce dendritic cell maturation and antigen presentation. Our results call for systematic re‐evaluation of the respective proportions and functions of non‐viral EVs and VLPs produced by murine tumors and their contribution to tumor progression. Synopsis: Tumor‐derived extracellular vesicles have been proposed to induce immune priming of antigen presenting cells, or to act as immuno‐suppressive agents. This study presents a comprehensive analysis of distinct subpopulations of extracellular vesicles (EVs) and non‐vesicular extracellular particles released by murine tumor cells and reveals presence of endogenous retrovirus‐derived components. Murine tumor cell lines commonly release endogenous retrovirus‐derived virus‐like particles (VLPs) alongside other EVs.Tumor‐derived VLPs and other EVs exhibit distinct effects on dendritic cells, with a mixed EV preparation, including larger vesicles and VLPs, proving most efficient for antigen transfer and dendritic cell‐mediated T cell activation.Non‐vesicular extracellular particles are ineffective in inducing antigen presentation and T cell activation by antigen‐presenting cells. [ABSTRACT FROM AUTHOR]

Genetics tools are used in applied conservation management for taxonomic identification, delineation of management units, management of wild populations, captive breeding and reintroduction and control of invasive species, disease and hybridisation.To assess the extent to which genetic tools are being used for applied conservation management, we conducted a systematic literature review of over 53,767 papers focussing on wildlife research that reported results on species delineation, translocations and population augmentation. We synthesised information on papers that used genetics tools in an expressly applied manner across all wildlife species.We found that the application of genetics tools in conservation management was biased towards fishes, mammals and birds and northern hemisphere locations, especially the United States and Europe.Despite genetics tools being a highly published topic, it was difficult to find published applications of these tools in both the primary and the grey literature. Of the 115 papers on 152 species that could be considered an applied use of a genetics tool expressly for conservation management, only 49 had definable applied outcomes. The remaining 66 made recommendations, but it was often unclear if the recommendations were ever used to make conservation management decisions because of the time‐lag between publication of the initial recommendation and publication of the results of the use of the tool in a conservation management situation, as well as the lack of dissemination in the primary literature.Our study highlights the relative low publication rate of applications of genetics tools compared to the general conservation genetics field. These tools appear to have either a low percentage of translations into publication ('conservation genetics publishing gap') or a poor uptake among wildlife conservation managers ('conservation genetics gap')—the two are indistinguishable in this review.Policy implications. Conservation genetics tools must be brought to the forefront of conservation policy and management. Users should support the use of systems and accessible databases to increase the uptake of genetics tools for conservation in applied management decisions for wildlife, reducing barriers to disseminating the results to other end users and interested parties. [ABSTRACT FROM AUTHOR]

Despite an enormous interest in understanding the bioactivity of extracellular vesicles (EV) in physiology and disease for the development of therapeutic applications, the impact of EV preparation methods remains minimally explored. In this study, we implemented density gradient ultracentrifugation combined with size‐exclusion chromatography (DG‐SEC), differential ultracentrifugation (dUC) and/or stand‐alone SEC (sSEC) to fractionate media conditioned by different cancer cells and/or cancer‐associated fibroblasts (CAF). EV‐enriched but protein‐depleted versus EV‐depleted but protein‐enriched DG‐SEC fractions, and EV‐containing dUC and sSEC preparations were quality controlled for particle number, protein concentration, selected protein composition and ultrastructure, characterized for their cytokine content, and dose‐dependently evaluated for monocyte‐derived dendritic cell (MoDC) maturation by measuring surface marker expression and/or cytokine secretion. EV preparations obtained by DG‐SEC from media conditioned by different cancer cell lines or CAF, were depleted from soluble immune suppressive cytokines such as VEGF‐A and MCP‐1 and potently stimulated MoDC maturation. In contrast, EV‐containing dUC or sSEC preparations were not depleted from these soluble cytokines and were unable to mature MoDC. Subsequent processing of dUC EV preparations by SEC dose‐dependently restored the immunomodulatory bioactivity. Overall, our results demonstrate that method‐dependent off‐target enrichment of soluble cytokines has implications for the study of EV immunomodulatory bioactivity and warrants careful consideration. [ABSTRACT FROM AUTHOR]

Transparent and conductive ZnO:Al thin films have been deposited by a reactive magnetron sputtering using the layer‐by‐layer growth method. The grown Al‐doped ZnO films of about 100 nm thickness on Si and glass substrates have been investigated with respect to the crystalline phase by X‐ray diffraction (XRD), surface morphology by atomic force microscopy (AFM), chemical bonding, and the electronic structure by measuring the X‐ray photoelectron spectroscopy (XPS) core‐level and valence‐band spectra of the ZnO:Al films. The influence of Al content in ZnO films on structure, optical, and XPS spectra, transport parameters n, μ, ρ have been studied. The weak temperature dependence of conductivity in the temperature range 77–300 K suggests that Al3+ is a fully ionized impurity that provides the values of electron concentration in the range 7 × 1019–2.44 × 1020 cm−3. Al electroactivity (EA) in ZnO films is diminishing with Al content increases. A strong decrease in Al EA from 60% to 30% is observed for ZnO:Al films within 0.93–1.22 at% of Al that indicates on the enhancement of concentration of acceptor native and/or neutral complex defects in ZnO. [ABSTRACT FROM AUTHOR]

The evolution of egg shape across birds has been associated with breeding ecology, body shape constraints and nest microclimate, among other factors. We model the effects of migratory status, climate, clutch size and egg volume on egg shape variation over the distribution of fork‐tailed flycatchers Tyrannus savana. Although migratory status and climatic variables appear to be influencing intraspecific egg shape, these effects are not significant when accounting for nest identity as a random factor (i.e. eggs from the same clutch are more similar than to other clutches). Moreover, the differences that we observe in egg shape are not explained by variation in egg size. Finally, within a breeding population of migratory fork‐tailed flycatchers, egg shape does not vary with respect to egg‐laying order and/or female wing length (standardized by weight). Egg shape is highly variable within populations of fork‐tailed flycatchers but not within clutches, suggesting that female traits, apart from migratory status and wing morphology, constrain egg shape variation. [ABSTRACT FROM AUTHOR]

Background: Liver shear stiffness measurement using magnetic resonance elastography (MRE) aids in the noninvasive diagnosis and staging of liver fibrosis. Inadequate breath‐holds can lead to inaccurate stiffness estimation and/or failed MRE exams. Purpose: To prospectively evaluate the performance of compressed sensitivity encoding (C‐SENSE) accelerated rapid MRE measurement of liver shear stiffness using displacement wave polarity‐inversion motion encoding. Study Type: Retrospective. Subjects: Eleven with liver disease and 10 asymptomatic subjects. Field Strength/Sequence: 1.5 T; gradient‐recalled‐echo (GRE) MRE. Assessment: All participants underwent: 1) two‐dimensional (2D) GRE MRE with inflow saturation using SENSE acceleration factor (R) of 2 (standard of care [SC]); 2) 2D rapid MRE with (RwS); and 3) without (RnS) inflow saturation using C‐SENSE R = 3; and 4) spatial three‐dimensional (3D) rapid MRE with inflow saturation (R3D) using C‐SENSE R = 4; with nominally identical spatial resolution and coverage. Image analyst (D.G., 2 years of experience) drew identical and maximal regions of interest (ROIs) in right hepatic lobe. Statistical Tests: Linear regression, intra‐class correlation coefficients (ICC), Bland–Altman analyses, and the Wilcoxon signed‐rank test were used to assess consistency and agreement of liver stiffness measurements for manually drawn identical and maximal ROIs. Results: In 21 participants (37 ± 14 years) with liver stiffness (2.3 ± 0.7 kPa), body mass index (BMI 27 ± 7 kg/m2), proton density fat fraction (PDFF 9 ± 9%), and T2* (27 ± 4 msec); rapid MRE sequences showed excellent agreement (ICC > 0.95) with SC MRE and no correlation (r2 < 0.1) of the differences (mean difference <0.2 kPa, <6%; limits of agreement <0.4 kPa, <16%) with BMI, PDFF, and T2*. Breath‐hold times were: 14 seconds (SC), 5 seconds (RnS), 7 seconds (RwS) per slice, and 16 seconds for the R3D acquisition. Data Conclusions: C‐SENSE accelerated GRE MRE sequences, using displacement wave polarity‐inversion motion encoding, produce equivalent measurements of liver stiffness and have potential clinical benefit in patients with limited breath‐holding capacity. Level of Evidence: 1 Technical Efficacy: Stage 1 [ABSTRACT FROM AUTHOR]

The development of gene editing technologies over the past years has allowed the precise and efficient insertion of transgenes into the genome of various cell types. Knock‐in approaches using homology‐directed repair and designer nucleases often rely on viral vectors, which can considerably impact the manufacturing cost and timeline of gene‐edited therapeutic products. An attractive alternative would be to use naked DNA as a repair template. However, such a strategy faces challenges such as cytotoxicity from double‐stranded DNA (dsDNA) to primary cells. Here, we sought to study the kinetics of transcription activator‐like effector nuclease (TALEN)‐mediated gene editing in primary T cells to improve nonviral gene knock‐in. Harnessing this knowledge, we developed a rapid and efficient gene insertion strategy based on either short single‐stranded oligonucleotides or large (2 Kb) linear naked dsDNA sequences. We demonstrated that a time‐controlled two‐step transfection protocol can substantially improve the efficiency of nonviral transgene integration in primary T cells. Using this approach, we achieved modification of up to ˜ 30% of T cells when inserting a chimeric antigen receptor (CAR) at the T‐cell receptor alpha constant region (TRAC) locus to generate 'off‐the shelf' CAR‐T cells. [ABSTRACT FROM AUTHOR]

Aim: Macroecological analyses provide valuable insights into factors that influence how parasites are distributed across space and among hosts. Amid large uncertainties that arise when generalizing from local and regional findings, hierarchical approaches applied to global datasets are required to determine whether drivers of parasite infection patterns vary across scales. We assessed global patterns of haemosporidian infections across a broad diversity of avian host clades and zoogeographical realms to depict hotspots of prevalence and to identify possible underlying drivers. Location: Global. Time period: 1994–2019. Major taxa studied: Avian haemosporidian parasites (genera Plasmodium, Haemoproteus, Leucocytozoon and Parahaemoproteus). Methods: We amalgamated infection data from 53,669 individual birds representing 2,445 species world‐wide. Spatio‐phylogenetic hierarchical Bayesian models were built to disentangle potential landscape, climatic and biotic drivers of infection probability while accounting for spatial context and avian host phylogenetic relationships. Results: Idiosyncratic responses of the three most common haemosporidian genera to climate, habitat, host relatedness and host ecological traits indicated marked variation in host infection rates from local to global scales. Notably, host ecological drivers, such as migration distance for Plasmodium and Parahaemoproteus, exhibited predominantly varying or even opposite effects on infection rates across regions, whereas climatic effects on infection rates were more consistent across realms. Moreover, infections in some low‐prevalence realms were disproportionately concentrated in a few local hotspots, suggesting that regional‐scale variation in habitat and microclimate might influence transmission, in addition to global drivers. Main conclusions: Our hierarchical global analysis supports regional‐scale findings showing the synergistic effects of landscape, climate and host ecological traits on parasite transmission for a cosmopolitan and diverse group of avian parasites. Our results underscore the need to account for such interactions, in addition to possible variation in drivers across regions, to produce the robust inference required to predict changes in infection risk under future scenarios. [ABSTRACT FROM AUTHOR]

Infants born very preterm (VPT) are at high risk of motor impairments such as cerebral palsy (CP), and diagnosis can take 2 years. Identifying in vivo determinants of CP could facilitate presymptomatic detection and targeted intervention. Our objectives were to derive micro‐ and macrostructural measures of sensorimotor white matter tract integrity from diffusion MRI at term‐equivalent age, and determine their association with early diagnosis of CP. We enrolled 263 VPT infants (≤32 weeks gestational age) as part of a large prospective cohort study. Diffusion and structural MRI were acquired at term. Following consensus guidelines, we defined early diagnosis of CP based on abnormal structural MRI at term and abnormal neuromotor exam at 3–4 months corrected age. Using Constrained Spherical Deconvolution, we derived a white matter fiber orientation distribution (fOD) for subjects, performed probabilistic whole‐brain tractography, and segmented nine sensorimotor tracts of interest. We used the recently developed fixel‐based (FB) analysis to compute fiber density (FD), fiber‐bundle cross‐section (FC), and combined fiber density and cross‐section (FDC) for each tract. Of 223 VPT infants with high‐quality diffusion MRI data, 14 (6.3%) received an early diagnosis of CP. The cohort's mean (SD) gestational age was 29.4 (2.4) weeks and postmenstrual age at MRI scan was 42.8 (1.3) weeks. FD, FC, and FDC for each sensorimotor tract were significantly associated with early CP diagnosis, with and without adjustment for confounders. Measures of sensorimotor tract integrity enhance our understanding of white matter changes that antecede and potentially contribute to the development of CP in VPT infants. [ABSTRACT FROM AUTHOR]

The small terrestrial gastropod Vertigo pseudosubstriata Ložek, 1954 is one of the rarest glacial indicator species in the Pleistocene of Central and Eastern Europe. In all, this species has been found at only about 15 sites in Europe. V. pseudosubstriata was initially described as a fossil in Central Europe and was discovered only later alive in Central Asia. With regard to its modern distribution, 25 habitats with V. pseudosubstriata have been examined in Tien Shan and in the central and southern Altai. These findings seem to capture the contemporary distribution of the species and provide information on the boundaries of its ecological requirements. These data are of great significance for the interpretation of the fossil assemblages. Since the few fossil specimens in Europe date from very different glacial periods in the Elsterian, Saalian Complex and Weichselian, it can be concluded that V. pseudosubstriata apparently immigrated in at least three distinct waves. Most of the Pleistocene specimens in eastern Central Europe and Eastern Europe are reported from archaeological sites of the Upper Middle Weichselian (Gravettian), roughly between 33 and 29 ka cal bp. In this paper, we review all reported modern and fossil occurrences and discuss the species' ecological range. [ABSTRACT FROM AUTHOR]

Purpose: Chemical shift-encoded MRI (CSE-MRI) is well-established to quantify proton density fat fraction (PDFF) as a quantitative biomarker of hepatic steatosis. However, temperature is known to bias PDFF estimation in phantom studies. In this study, strategies were developed and evaluated to correct for the effects of temperature on PDFF estimation through simulations, temperature-controlled experiments, and a multi-center, multi-vendor phantom study. Theory and Methods: A technical solution that assumes and automatically estimates a uniform, global temperature throughout the phantom is proposed. Computer simulations modeled the effect of temperature on PDFF estimation using magnitude-, complex-, and hybrid-based CSE-MRI methods. Phantom experiments were performed to assess the temperature correction on PDFF estimation at controlled phantom temperatures. To assess the temperature correction method on a larger scale, the proposed method was applied to data acquired as part of a nine-site multi-vendor phantom study and compared to temperature-corrected PDFF estimation using an a priori guess for ambient room temperature. Results: Simulations and temperature-controlled experiments show that as temperature deviates further from the assumed temperature, PDFF bias increases. Using the proposed correction method and a reasonable a priori guess for ambient temperature, PDFF bias and variability were reduced using magnitude-based CSE-MRI, across MRI systems, field strengths, protocols, and varying phantom temperature. Complex and hybrid methods showed little PDFF bias and variability both before and after correction. Conclusion: Correction for temperature reduces temperature-related PDFF bias and variability in phantoms across MRI vendors, sites, field strengths, and protocols for magnitude-based CSE-MRI, even without a priori information about the temperature. [ABSTRACT FROM AUTHOR]

A 2D electron gas with spin–orbit interaction (SOI) is known to form an anisotropic system with van Hove singularities controllable by a parallel magnetic field. The conductivity tensors of this system in the presence of both Rashba and Dresselhaus SOIs is studied. It is found that the diagonal elements of the conductivity tensor have sharp dips when the Fermi level passes through the singularity point of a spectrum. The energy position of these dips at different orientations of the magnetic field allows one to determine both SOI constants and the Landé g‐factor. The dependencies of the surface charge concentration on the Fermi level show a sharp change in the slope near the minimum of the spectrum due to the jumps of the density of states, while the van Hove singularities are not noticeable. In a zero magnetic field, the conductivity tensor has off‐diagonal terms which change the sign when the Fermi level passes the saddle points of the spectrum. The off‐diagonal terms evidence the appearance of the Hall voltage caused by the anisotropy of the Fermi surface and the scattering process. [ABSTRACT FROM AUTHOR]

Cells release diverse types of extracellular vesicles (EVs), which transfer complex signals to surrounding cells. Specific markers to distinguish different EVs (e.g. exosomes, ectosomes, enveloped viruses like HIV) are still lacking. We have developed a proteomic profiling approach for characterizing EV subtype composition and applied it to human Jurkat T cells. We generated an interactive database to define groups of proteins with similar profiles, suggesting release in similar EVs. Biochemical validation confirmed the presence of preferred partners of commonly used exosome markers in EVs: CD81/ADAM10/ITGB1, and CD63/syntenin. We then compared EVs from control and HIV‐1‐infected cells. HIV infection altered EV profiles of several cellular proteins, including MOV10 and SPN, which became incorporated into HIV virions, and SERINC3, which was re‐routed to non‐viral EVs in a Nef‐dependent manner. Furthermore, we found that SERINC3 controls the surface composition of EVs. Our workflow provides an unbiased approach for identifying candidate markers and potential regulators of EV subtypes. It can be widely applied to in vitro experimental systems for investigating physiological or pathological modifications of EV release. SYNOPSIS: Specific markers to distinguish extracellular vesicle (EV) diversity released at homeostasis or pathophysiological perturbation are currently lacking. This profiling/network analysis establishes a proteomic workflow to characterise the EV protein inventory of human T cells before and after infection by HIV‐1. Centrifugal separation of EV subtypes from Jurkat T cells allows quantitative proteomic profiling without additional purification.An interactive database calculates nearest neighbours of each EV‐protein and plots respective protein networks.Proteomic profiling of EVs under two experimental conditions allows identification of EV subtype‐specific modifications in protein composition.Comparative profiling of EVs from HIV‐1‐infected versus control Jurkat T cells reveals alterations in host cell protein inclusion into viral particles. [ABSTRACT FROM AUTHOR]

There is currently a demand for flexible biomedical sensors. Characteristics as soft, thin, elastic, flexible and comfortable to the contact with skin should be matched with performance and ultimately made of sustainable, and biocompatible materials. In this work, chitosan as a flexible biodegradable polymeric matrix was combined with ferroelectric BaTiO3 particles obtained by hydrothermal synthesis to prepare flexible films. The biocomposites have high flexibility and the addition of particles improves the elasticity of pristine chitosan films. Of relevance towards the targeted application, the biocomposites exhibit a better resistance to water than chitosan. The dielectric permittivity increases with the addition of BaTiO3 particles. The observation of d33 and d15 by PFM, confirms the presence of piezoelectric domains corresponding to the location of BaTiO3 particles. These results contribute to the understanding of the role of functional oxides on the chemical and physical behavior of biobased polymers, creating opportunities to design optimized and more sustainable flexible piezoelectric sensor films. [ABSTRACT FROM AUTHOR]

Purpose: To design a new 2D gradient recalled echo MR elastography (MRE) pulse sequence with inflow saturation for measuring liver stiffness in half the breath‐hold time compared to standard of care (SC) 2D GRE MRE sequences. Methods: FASTWALTZ (fusing acceleration and saturation techniques with wave amplitude labeling of time‐shifted zeniths) MRE employs an interleaved dual TR strategy with wave amplitude labeling and compressed SENSE undersampling to reduce breath‐hold time while incorporating inflow saturation to suppress flow artifacts. The sequence was implemented and compared with SC MRE both in phantoms and in vivo in 5 asymptomatic volunteers. Stiffness values, region of interest size, and breath‐hold times were compared between sequences. Results: Stiffness values were comparable between FASTWALTZ and SC MRE for both phantoms and in‐vivo data. In volunteers, the group mean stiffness values at 60 Hz and region of interest size were 1.96 ± 0.30 kilopascals and 2279 ± 516 mm2 for SC MRE, and 1.95 ± 0.29 kilopascals and 2061 ± 464 mm2 for FASTWALTZ. Breath‐hold duration for FASTWALTZ was 6.3 s compared to 13.3 s for SC MRE. Conclusion: FASTWALTZ provides comparable stiffness values in half the breath‐hold time compared to SC MRE and may have clinical benefits in patients with limited breath‐holding capacity. [ABSTRACT FROM AUTHOR]

Summary: Methane emission from trees may partially or completely offset the methane sink in upland soils, the only process that has been regularly included in methane budgets for forest ecosystems. Our objective was to analyze multiple biogeochemical processes that influence the production, oxidation and transport of methane in a riparian cottonwood ecosystem and its adjacent river.We combined chamber flux measurements on tree stems, forest soil and the river surface with eddy covariance measurements of methane net ecosystem exchange. In addition, we tested whether methanogens were present in cottonwood stems, shallow soil layers and alluvial groundwater.Average midday peak in net methane emission measured by eddy covariance was c. 12 nmol m−2 s−1. The average uptake of methane by soils (0.87 nmol m−2 s−1) was largely offset by tree stem methane emission (0.75 nmol m−2 s−1). There was evidence of methanogens in tree stems but not in shallow soil.Growing season (May–September) cumulative net methane emission (17.4 mmol CH4 m−2) included methane produced in cottonwood stems and methane input to the nocturnal boundary layer from the forest and the adjacent river. The multiple processes contributing to methane emission illustrated the linked nature of these adjacent terrestrial and aquatic ecosystems. [ABSTRACT FROM AUTHOR]

SARS‐CoV‐2 entry is mediated by binding of the spike protein (S) to the surface receptor ACE2 and subsequent priming by host TMPRSS2 allowing membrane fusion. Here, we produced extracellular vesicles (EVs) exposing ACE2 and demonstrate that ACE2‐EVs are efficient decoys for SARS‐CoV‐2 S protein‐containing lentivirus. Reduction of infectivity positively correlates with the level of ACE2, is much more efficient than with soluble ACE2 and further enhanced by the inclusion of TMPRSS2. [ABSTRACT FROM AUTHOR]

Gentiana is a sub‐cosmopolitan temperate genus among the most species‐rich in Gentianaceae. Although molecular data (produced via Sanger sequencing) allowed the resolution of phylogenetic relationships between Gentiana and other genera in subtribe Gentianinae, the validity of sections within the genus remains largely untested. In this study, we evaluated the monophyly of all 14 sections attributed to Gentiana, using 294 unlinked anchored loci, the nuclear ribosomal DNA (rDNA) cistron as well as plastid genomes, all produced by anchored hybrid enrichment. We reconstructed phylogenetic relationships by conducting maximum likelihood and Bayesian analyses. These analyses represent a significant improvement over previous taxonomic studies using molecular tools. Our results partly correspond to traditional taxonomic treatments, with several sections being well supported as monophyletic, including Gentiana sect. Calathianae, sect. Ciminalis, sect. Cruciata, sect. Frigida, sect. Gentiana and sect. Pneumonanthe. In contrast, G. sect. Isomeria, sect. Microsperma and sect. Monopodiae were found to be polyphyletic, whereas sect. Dolichocarpa and sect. Fimbricorona were nested within sect. Chondrophyllae. We here provide new taxonomic treatments for these sections, mostly based upon the traditional delineation of their series, which were recovered as monophyletic. In our new treatment, Gentiana encompasses 13 sections. A new determination key to the sections of Gentiana is provided. [ABSTRACT FROM AUTHOR]

Introduction: This study examined the influence of training in an occupation‐centred model on the practice of occupational therapists working in a cancer hospital. There is an increased need for occupation‐based rehabilitation services for individuals with and surviving cancer. Incorporating an occupation‐centred model into practice has unique challenges for occupational therapists working in oncology settings. Utilizing an occupation‐centred model of practice may influence the therapeutic reasoning of occupational therapists. Methods: A generic qualitative inquiry (Patton, 2015) was used to examine therapeutic reasoning as related to post‐professional training in a specific occupation‐centred model, the Model of Human Occupation (MOHO). Initially, ten occupational therapists with various levels of experience, working across populations in a large cancer centre completed a training session about the MOHO. This was followed by participation in monthly focus groups with an emphasis on the use of MOHO in daily practice (Taylor, 2017). Focus group sessions were video recorded and transcribed. The transcripts were then analysed using open coding and theme generation (Patton, 2015). Results: Three major themes were extracted from the data during the thematic analysis: understanding and using MOHO language; challenges in incorporating a conceptual model of occupation‐centred practice in an oncology setting; and therapeutic reasoning implications. Patterns in the themes indicated a progression from learning the model, to applying the model, to reflection on practice. Conclusion: Post‐professional training in an occupation‐based model influenced the therapeutic reasoning and practice of occupational therapists in an oncology setting. [ABSTRACT FROM AUTHOR]

A novel resonance method for accurate determining a complex permittivity of the samples over the entire X‐band is proposed. This method uses the difference in the resonant mode perturbation when the sample moves in the field of standing wave of a rectangular resonator thereby leading to changing resonance frequencies and the amplitudes of resonant modes for each position of the sample in the resonator. Comparison of measured data with the calculated ones, in which permittivity (ε) and loss tangent (tan δ) are the variable parameters, allows for building the discrepancy coefficient σ as the function of ε and tan δ. Sought‐for values ε and tan δ of the sample are determined in points corresponding the minimа of the aforementioned functions. The procedure like that is used for all resonant modes excited in the resonator in the analyzed frequency band, which allows for obtaining the frequency dependences ε and tan δ. The measurements are carried out in the frequency band 8‐12 GHz for a number of solid dielectrics. Permittivity and loss tangent are determined with an error that does not exceed 0.5% and 5%, respectively. [ABSTRACT FROM AUTHOR]

An enduring challenge of public administration research is examining whether public management affects the delivery of public policy results. This study extends managerial influence to include public policy delivery in an active conflict environment. Individual manager training is critical in conflict environments because limited bureaucratic capacity and general environmental confusion are common. Organizations under stress use substitute managers. We argue that substitute managers' effectiveness is conditioned by two factors: managerial capability and networking capability. We examine substitute managers in a unique context, the US–Iraq War. Managers coordinated private military and security companies (PMSCs) to provide coalition forces and the civilian population with multiple services. We argue that managers with prior management experience and network capability are more effective substitute managers. The results suggest that managers with prior experience and networking capability are associated with decreases in civilian casualties. The results provide important policy insights into public management and defence policy. [ABSTRACT FROM AUTHOR]

Herein, the structural effect of autologous platelet-rich plasma (PRP) on posttraumatic skeletal muscle regeneration in rats with chronic hyperglycemia (CH) was tested. 130 white laboratory male rats divided into four groups (I—control; II—rats with CH; III—rats with CH and PRP treatment; and IV—rats for CH confirmation) were used for the experiment. CH was simulated by streptozotocin and nicotinic acid administration. Triceps surae muscle injury was reproduced by transverse linear incision. Autologous PRP was used in order to correct the possible negative CH effect on skeletal muscle recovery. On the 28th day after the injury, the regenerating muscle fiber and blood vessel number in the CH+PRP group were higher than those in the CH rats. However, the connective tissue area in the CH group was larger than that in the CH+PRP animals. The amount of agranulocytes in the regenerating muscle of the CH rats was lower compared to that of the CH+PRP group. The histological analysis of skeletal muscle recovery in CH+PRP animals revealed more intensive neoangiogenesis compared to that in the CH group. Herewith, the massive connective tissue development and inflammation signs were observed within the skeletal muscle of CH rats. Obtained results suggest that streptozotocin-induced CH has a negative effect on posttraumatic skeletal muscle regeneration, contributing to massive connective tissue development. The autologous PRP injection promotes muscle recovery process in rats with CH, shifting it away from fibrosis toward the complete muscular organ repair. [ABSTRACT FROM AUTHOR]

Optical properties of as‐grown high nitrogen‐doped ZnO:Al,N films (with a variation of nitrogen concentration from 2.3 to 4.3 atomic %) are studied by Raman, photoluminescence, and Fourier‐transform infrared spectroscopy (FTIR). The intensity of mode A1LO, peaked at 580 cm−1, increases with increasing nitrogen concentration. The silent mode B1low at 275 cm−1 is clearly observed testifying increased disorder‐activated scattering in ZnO. Photoluminescence spectra reveal near‐band edge emission as well as several defect‐related bands, the intensity of which increases with nitrogen content. The blue band (2.61 eV) can be related to the transition from shallow donor level to deep nitrogen acceptor level. Also, incorporation of nitrogen in ZnO lattice causes appearance of both Zni and Oi defects responsible for violet (3.08 eV) and yellow (2.16 eV) emission band, respectively. At the same time near‐band edge emission of ZnO:Al,N films is not suppressed by simultaneously introduced Al and N impurities. Al compensates distortions in ZnO crystal lattice caused by nitrogen doping and, thus, stabilizes near‐band edge emission. [ABSTRACT FROM AUTHOR]

Introduction. Unsatisfactory consequences of bone regeneration disorders in diabetes mellitus (DM) patients, their high prevalence, complication number, and difficulties in treatment require further study and deeper understanding of reparative osteogenesis mechanisms under chronic hyperglycemia and finding new effective and affordable approaches to their treatment. Therefore, the aim of our work was to study the histological, ultramicroscopic, and histomorphometric features of reparative osteogenesis in rats with chronic hyperglycemia (CH), as well as to investigate the possibility of platelet-rich plasma (PRP) use in a fracture area in order to correct the negative effects of CH on reparative osteogenesis processes. Study Object and Methods. The studies were performed on 70 white laboratory rats, mature males, which were divided into the following groups: control group, animals with posttraumatic tibial defect under conditions of CH exposure, rats with experimental CH that were administered with PRP into the bone defect, and animals for the assessment of glucose homeostasis and confirmation of simulated CH. Light microscopy was performed using an Olympus BH-2 microscope (Japan). Ultramicroscopic examination was performed using REM-102 scanning electron microscope. The statistical analysis was performed using SPSS-17 software package. Results. The formation of new bone tissue in animals with CH did not occur after two weeks. Only on the 30th day of reparative osteogenesis the newly formed woven bone tissue was 61.54% of the total regenerated area. It was less than the reference value by 22.89% (P < 0.001). On the 14th day of reparative osteogenesis, the regenerated area in a group of animals with CH and PRP injection consisted of connective tissue by 68.94% (4.94% less than in animals with CH (P < 0.001)) and woven bone tissue by 31.06%, (13.51% less than in the control group (P < 0.001)). On the 30th day, the area of woven bone tissue in a regenerate of this group was less than that of the control group by 12.41% (P < 0.001). Conclusion. Thus, chronic hyperglycemia contributes to inflammation delay within the bone defect site, which makes the process of reparative osteogenesis more prolonged. The results of chronic hyperglycemia effect on bone regeneration are also impairment of osteogenic cell proliferation and shift of their differentiation towards the fibrocartilage regenerate formation. The PRP corrects the negative impact of chronic hyperglycemia on reparative osteogenesis, promoting more rapid inflammatory infiltrate removal from the bone defect site and osteogenic beam formation and remodeling of woven bone into lamellar membranous bone tissue. [ABSTRACT FROM AUTHOR]

To investigate the evolutionary diversification and morphological evolution of grass supertribe Poodae (subfam. Pooideae, Poaceae) we conducted a comprehensive molecular phylogenetic analysis including representatives from most of its accepted genera. We focused on generating a DNA sequence dataset of plastid matK gene–3′trnK exon and trnL‐trnF regions and nuclear ribosomal (nr) ITS1–5.8S gene–ITS2 and ETS that was taxonomically overlapping as completely as possible (altogether 257 species). The idea was to infer whether phylogenetic trees or certain clades based on plastid and nrDNA data correspond with each other or discord, revealing signatures of past hybridization. The datasets were analysed separately, in combination, by excluding taxa with discordant placements in the individual gene trees and with duplication of these taxa in a way that each duplicate has only one data partition (plastid or nrDNA). We used maximum likelihood, maximum parsimony and Bayesian approaches. Instances of severe conflicts between the phylogenetic trees derived from both datasets, some of which have been noted earlier, point to hybrid origin of several lineages such as the ABCV clade encompassing several subtribes and subordinate clades, subtribes Airinae, Anthoxanthinae, Antinoriinae, subtr. nov., Aristaveninae, Avenulinae, subtr. nov., Helictochloinae, subtr. nov., Holcinae, Phalaridinae, Scolochloinae, Sesleriinae, Torreyochloinae and genera Arctopoa, Castellia, Graphephorum, Hyalopodium, Lagurus, Macrobriza, Puccinellia plus Sclerochloa, Sesleria, Tricholemma, Tzveleviochloa, etc. 'Calamagrostis' flavens appears to be an intergeneric hybrid between Agrostis and Calamagrostis. Analyses excluding all lineages with demonstrably cytonuclear discordance revealed three supported main clades within Poodae that were present in both the plastid and nrDNA trees. They fully corresponded in their delineation but were phylogenetically differently arranged, pointing to hybrid origin of one of them. We propose to consider these main clades in classification as separate tribes Aveneae, Poeae s.str. and Festuceae with a phylogenetic arrangement of Aveneae(Poeae,Festuceae) in plastid versus Festuceae(Aveneae,Poeae) in nrDNA trees. Phylogenetic incongruence of the plastid and nuclear markers extends across all hierarchical taxonomic levels of Poodae, ranging from species (not studied here) to genera, subtribes and tribes, therefore the deepest taxonomic levels, emphasizing the enormous significance of reticulate evolution in this large group of grasses. A partly revised classification is presented, including the introduction of a new tribe Festuceae and a re‐instatement of tribe Aveneae. Following a comparatively narrow delineation of preferably monophyletic subtribes, Antinoriinae, Avenulinae, Brizochloinae, Helictochloinae and Hypseochloinae are described as new. New genera are Arctohyalopoa and Hyalopodium. New combinations are Anthoxanthum glabrum subsp. sibiricum, A. nitens subsp. kolymense, Arctohyalopoa ivanovae, A. jurtzevii, A. lanatiflora, A. momica, Colpodium biebersteinianum, C. kochii, C. pisidicum, C. trichopodum, C. verticillatum, Dupontia fulva, Festuca masafuerana, F. robinsoniana, Graphephorum canescens, G. cernuum, Hyalopodium araraticum, Paracolpodium baltistanicum, Parapholis cylindrica, P. ×pauneroi. Festuca dolichathera and F. masatierrae are new names. [ABSTRACT FROM AUTHOR]

Avena breviaristata, collected only once (1882) in Algeria and never re‐collected since, is a very mysterious grass species because unfortunately even the type specimen got lost 60–80 years ago. Morphological information on this species was thus based on a few published descriptions, which made it difficult, however, to correctly infer the genus affiliation of this morphologically odd species. Avena breviaristata became affiliated in the past with various oat‐like genera (Avenula, Helictotrichon, Tricholemma). Due to the recent rediscovery of the type specimen at the P herbarium and the opportunity to study this specimen, we report here on the morphological characters of A. breviaristata, underpinned by meaningful illustrations. They are discussed in comparison with the morphology of representative species of the above‐mentioned genera. Uncommon characters of the spikelets (type of disarticulation of the rachilla, lemma structure, lodicules) and to some extent of the inflorescences, leaves and leaf sheaths support the inclusion of A. breviaristata in the North African genus Tricholemma. Considering biogeography, T. breviaristatum from the arid Hauts Plateaux in Algeria is a highly xeromorphic counterpart of the mesomorphic species T. jahandiezii, which is confined to higher altitudes of the rather humid Moyen Atlas in Morocco. This underlines the status of Tricholemma as a relic endemic. Our morphological survey supports the classification of Avenula (only A. pubescens) as separate from Helictotrichon s.str. and Helictochloa. Moreover, morphological evidence does not support an origin of A. pubescens by intergeneric hybridization between the latter genera as hypothesized in some prior studies. Especially the glabrous palea, the special shape of the lodicules and the structure of the awn show no intermediacy. The complicated history of the type collection of T. breviaristatum and the role of botanical authors are given. [ABSTRACT FROM AUTHOR]

Geographic variation in environmental conditions as well as host traits that promote parasite transmission may impact infection rates and community assembly of vector‐transmitted parasites.Identifying the ecological, environmental and historical determinants of parasite distributions and diversity is therefore necessary to understand disease outbreaks under changing environments. Here, we identified the predictors and contributions of infection probability and phylogenetic diversity of Leucocytozoon (an avian blood parasite) at site and species levels across the New World.To explore spatial patterns in infection probability and lineage diversity for Leucocytozoon parasites, we surveyed 69 bird communities from Alaska to Patagonia. Using phylogenetic Bayesian hierarchical models and high‐resolution satellite remote‐sensing data, we determined the relative influence of climate, landscape, geography and host phylogeny on regional parasite community assembly.Infection rates and parasite diversity exhibited considerable variation across regions in the Americas. In opposition to the latitudinal gradient hypothesis, both the diversity and prevalence of Leucocytozoon parasites decreased towards the equator. Host relatedness and traits known to promote vector exposure neither predicted infection probability nor parasite diversity. Instead, the probability of a bird being infected with Leucocytozoon increased with increasing vegetation cover (NDVI) and moisture levels (NDWI), whereas the diversity of parasite lineages decreased with increasing NDVI. Infection rates and parasite diversity also tended to be higher in cooler regions and higher latitudes.Whereas temperature partially constrains Leucocytozoon diversity and infection rates, landscape features, such as vegetation cover and water body availability, play a significant role in modulating the probability of a bird being infected. This suggests that, for Leucocytozoon, the barriers to host shifting and parasite host range expansion are jointly determined by environmental filtering and landscape, but not by host phylogeny. Our results show that integrating host traits, host ancestry, bioclimatic data and microhabitat characteristics that are important for vector reproduction are imperative to understand and predict infection prevalence and diversity of vector‐transmitted parasites. Unlike other vector‐transmitted diseases, our results show that Leucocytozoon diversity and prevalence will likely decrease with warming temperatures. [ABSTRACT FROM AUTHOR]

Background: Magnetic resonance elastography (MRE) has proven to be useful for assessing chronic liver disease. However, MRE images are acquired with breath-holding (BH) to limit respiratory motion artifacts, which may be difficult in some patients.Purpose: To implement a respiratory-triggered (RT) spin-echo echo-planar imaging (SE-EPI) MRE technique and to validate its performance through comparison to a BH SE-EPI MRE technique.Study Type: Prospective feasibility study.Subjects: Twenty-three adult volunteers (18 without and 5 with liver disease).Field Strength/sequences: 1.5 T Philips Ingenia MR scanner; RT and BH SE-EPI MRE sequences.Assessment: Four axial images were obtained through the middle of the liver with each technique. Liver stiffness measurements (in kPa) were made from elastograms, with 95% confidence maps overlaid, for both MRE sequences.Statistical Tests: Liver stiffness measurements were compared using the paired t-test (two-sided). Absolute agreement between the two techniques was evaluated using Lin's concordance coefficient (rc ). Bland-Altman analysis was used to assess the mean bias between the techniques and 95% limits of agreement, using BH MRE as the reference standard.Results: There was excellent agreement (rc = 0.98; 95% confidence interval: 0.96-0.99) between RT and BH SE-EPI MRE. Mean (±SD) stiffness values from BH and RT SE-EPI MRE techniques were 2.40 ± 1.15 kPa and 2.37 ± 1.06 kPa, respectively, with no significant difference (P = 0.54) and no significant bias (mean bias of +0.03 kPa; 95% limits of agreement: -0.39 to 0.45 kPa). Measurable regions of interest in the liver were slightly smaller with the RT technique (mean difference of 1.91 cm2 ; P = 0.04).Data Conclusion: RT SE-EPI MRE is feasible and yields comparable results to BH SE-EPI MRE.Level Of Evidence: 1 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2019;50:391-396. [ABSTRACT FROM AUTHOR]

The Cyathocotylidae is a globally distributed family of digeneans parasitic as adults in fish, reptiles, birds and mammals in both freshwater and marine environments. Molecular phylogenetic analysis of interrelationships among cyathocotylids is lacking with only a few species included in previous studies. We used sequences of the nuclear 28S rRNA gene to examine phylogenetic affinities of 11 newly sequenced taxa of cyathocotylids and the closely related family Brauninidae collected from fish, reptiles, birds and dolphins from Australia, Southeast Asia, Europe, North America and South America. This is the first study to provide sequence data from adult cyathocotylids parasitic in fish and reptiles. Our analyses demonstrated that the members of the genus Braunina (family Brauninidae) belong to the Cyathocotylidae, placing the Brauninidae into synonymy with the Cyathocotylidae. In addition, our DNA sequences supported the presence of a second species in the currently monotypic Braunina. Our phylogeny revealed that Cyathocotyle spp. from crocodilians belong to a separate genus (Suchocyathocotyle, previously proposed as a subgenus) and subfamily (Suchocyathocotylinae subfam. n.). Morphological study of Gogatea serpentum indicum supported its elevation to species as Gogatea mehri. The phylogeny did not support Holostephanoides within the subfamily Cyathocotylinae; instead, Holostephanoides formed a strongly supported clade with members of the subfamily Szidatiinae (Gogatea and Neogogatea). Therefore, we transfer Holostephanoides into the Szidatiinae. DNA sequence data revealed the potential presence of cryptic species reported under the name Mesostephanus microbursa. Our phylogeny indicated at least two major host switching events in the evolutionary history of the subfamily Szidatiinae which likely resulted in the transition of these parasites from birds to fish and snakes. Likewise, the transition to dolphins by Braunina represents another major host switching event among the Cyathocotylidae. In addition, our phylogeny revealed more than a single transition between freshwater and marine environments demonstrated in our dataset by Braunina and some Mesostephanus. [ABSTRACT FROM AUTHOR]

Geological carbon storage (GCS) refers to the technology of capturing man‐made carbon dioxide (CO2) emissions, typically from stationary power sources, and storing such emissions in deep underground reservoirs. GCS is an approach being explored globally as a defense mechanism against climate change projections, although it is not without its critics. An important focus has been recently placed on understanding the coupling between rock–fluid geochemical alterations and mechanical changes for CO2 storage schemes in saline aquifers. This article presents a review of the current state of knowledge regarding CO2‐induced geochemical reactions in subsurface reservoirs, and their potential impact on mechanical properties and microseismic events at CO2 storage sites. This review focuses, in particular, on the current state of the art in fluid–rock interactions within the GCS context. Key issues to be addressed include geochemical reactions and the alteration of transport and mechanical properties. Specific review topics include the swelling of clays, the prediction of dissolution and precipitation reaction rates, CO2‐induced changes in porosity and permeability, constitutive models of chemo–mechanical interactions in rock, and correlations between geochemical reactions and induced seismicity. The open questions in the field are emphasized, and new research needs are highlighted. © 2019 Society of Chemical Industry and John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Identifying the ecological factors that shape parasite distributions remains a central goal in disease ecology. These factors include dispersal capability, environmental filters and geographic distance. Using 520 haemosporidian parasite genetic lineages recovered from 7,534 birds sampled across tropical and temperate South America, we tested (a) the latitudinal diversity gradient hypothesis and (b) the distance–decay relationship (decreasing proportion of shared species between communities with increasing geographic distance) for this host–parasite system. We then inferred the biogeographic processes influencing the diversity and distributions of this cosmopolitan group of parasites across South America. We found support for a latitudinal gradient in diversity for avian haemosporidian parasites, potentially mediated through higher avian host diversity towards the equator. Parasite similarity was correlated with climate similarity, geographic distance and host composition. Local diversification in Amazonian lineages followed by dispersal was the most frequent biogeographic events reconstructed for haemosporidian parasites. Combining macroecological patterns and biogeographic processes, our study reveals that haemosporidian parasites are capable of circumventing geographic barriers and dispersing across biomes, although constrained by environmental filtering. The contemporary diversity and distributions of haemosporidian parasites are mainly driven by historical (speciation) and ecological (dispersal) processes, whereas the parasite community assembly is largely governed by host composition and to a lesser extent by environmental conditions. [ABSTRACT FROM AUTHOR]

Parasites with low host specificity (e.g. infecting a large diversity of host species) are of special interest in disease ecology, as they are likely more capable of circumventing ecological or evolutionary barriers to infect new hosts than are specialist parasites. Yet for many parasites, host specificity is not fixed and can vary in response to environmental conditions. Using data on host associations for avian malaria parasites (Apicomplexa: Haemosporida), we develop a hierarchical model that quantifies this environmental dependency by partitioning host specificity variation into region‐ and parasite‐level effects. Parasites were generally phylogenetic host specialists, infecting phylogenetically clustered subsets of available avian hosts. However, the magnitude of this specialisation varied biogeographically, with parasites exhibiting higher host specificity in regions with more pronounced rainfall seasonality and wetter dry seasons. Recognising the environmental dependency of parasite specialisation can provide useful leverage for improving predictions of infection risk in response to global climate change. [ABSTRACT FROM AUTHOR]

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Understanding how pathogens and parasites diversify through time and space is fundamental to predicting emerging infectious diseases. Here, we use biogeographic, coevolutionary and phylogenetic analyses to describe the origin, diversity, and distribution of avian malaria parasites in the most diverse avifauna on Earth. We first performed phylogenetic analyses using the mitochondrial cytochrome b (cyt b) gene to determine relationships among parasite lineages. Then, we estimated divergence times and reconstructed ancestral areas to uncover how landscape evolution has shaped the diversification of Parahaemoproteus and Plasmodium in Amazonia. Finally, we assessed the coevolutionary patterns of diversification in this host–parasite system to determine how coevolution may have influenced the contemporary diversity of avian malaria parasites and their distribution among Amazonian birds. Biogeographic analysis of 324 haemosporidian parasite lineages recovered from 4178 individual birds provided strong evidence that these parasites readily disperse across major Amazonian rivers and this has occurred with increasing frequency over the last five million years. We also recovered many duplication events within areas of endemism in Amazonia. Cophylogenetic analyses of these blood parasites and their avian hosts support a diversification history dominated by host switching. The ability of avian malaria parasites to disperse geographically and shift among avian hosts has played a major role in their radiation and has shaped the current distribution and diversity of these parasites across Amazonia. [ABSTRACT FROM AUTHOR]

1. Classical research on animal toxicity has focused on the role of toxins in protection against predators, but recent studies suggest these same compounds can offer a powerful defense against parasites and infectious diseases. 2. Newts in the genus Taricha are brightly coloured and contain the potent neurotoxin, tetrodotoxin (TTX), which is hypothesized to have evolved as a defense against vertebrate predators such as garter snakes. However, newt populations often vary dramatically in toxicity, which is only partially explained by predation pressure. 3. The primary aim of this study was to evaluate the relationships between TTX concentration and infection by parasites. By systematically assessing micro- and macroparasite infections among 345 adult newts (sympatric populations of Taricha granulosa and T. torosa), we detected 18 unique taxa of helminths, fungi, viruses and protozoans. 4. For both newt species, per-host concentrations of TTX, which varied from undetectable to >60 μg/cm² skin, negatively predicted overall parasite richness as well as the likelihood of infection by the chytrid fungus, Batrachochytrium dendrobatidis, and ranavirus. No such effect was found on infection load among infected hosts. Despite commonly occurring at the same wetlands, T. torosa supported higher parasite richness and average infection load than T. granulosa. Host body size and sex (females > males) tended to positively predict infection levels in both species. For hosts in which we quantified leucocyte profiles, total white blood cell count correlated positively with both parasite richness and total infection load. 5. By coupling data on host toxicity and infection by a broad range of micro- and macroparasites, these results suggest that--alongside its effects on predators--tetrodotoxin may help protect newts against parasitic infections, highlighting the importance of integrative research on animal chemistry, immunological defenses and natural enemy ecology. [ABSTRACT FROM AUTHOR]

Parasite distributions depend on the local environment in which host infection occurs, and the surrounding landscape over which hosts move and transport their parasites. Although host and landscape effects on parasite prevalence and spatial distribution are difficult to observe directly, estimation of such relationships is necessary for understanding the spread of infections and parasite-habitat associations. Although parasite distributions are necessarily nested within host distributions, direct environmental influences on local infection or parasite effects on host dispersal could lead to distinct landscape or habitat relationships relative to their hosts. Our aim was to determine parasite spatial structure across a contiguous prairie by statistical modeling of parasite-landscape relationships combined with analysis of population genetic structure. We sampled northern leopard frogs (Lithobates pipiens) and wood frogs (L. sylvaticus) for host-specific lung nematodes (Rhabdias ranae and R. bakeri; respectively) across the Sheyenne National Grassland in southeastern North Dakota and developed primers for 13 microsatellite loci for Rhabdias. The two Rhabdias species exhibited different correlations with landscape characteristics that conformed with that of their hosts, indicating transmission is driven by host ecology, probably density, and not directly by the environment. There was evidence for localized, patchy spatial genetic structure, but no broader-scale geographic patterns, indicating no barriers to host and parasite dispersal. Nematodes cohabitating in an individual frog were most genetically similar. Worms within the same wetland were also genetically similar, indicating localized transmission and resulting wetland-scale patchiness are not completely obscured by broad-scale host-parasite dispersal. Beyond individual wetlands, we found no evidence of genetic isolation-by-distance or patchiness at the landscape-scale. [ABSTRACT FROM AUTHOR]

Background: The objective of this study was to determine if a change in cryoprecipitate transfusion policy impacts donor exposure and fibrinogen level in a neonatal intensive care unit (NICU) population.Study Design and Methods: The cryoprecipitate policy was changed from transfusing 10ml/kg to a maximum of 1 unit per transfusion in January 2013. Data were obtained via retrospective chart review of all infants receiving cryoprecipitate transfusions from January 2008 to February 2015 in the NICU at Christiana Hospital.Results: A total of 103 neonates received a total of 144 cryoprecipitate transfusions. Before the policy change, term babies were more likely to be exposed to more than one donor compared to preterm babies (75% vs. 6%, p < 0.01). After the policy change, no babies were exposed to greater than one donor per transfusion and there were similar increases in posttransfusion fibrinogen level as before the policy change.Conclusion: Limiting cryoprecipitate transfusions to 1 unit per transfusion decreased donor exposure in infants without negatively impacting posttransfusion fibrinogen levels. This is especially evident in term neonates. [ABSTRACT FROM AUTHOR]

For the first time, PbCdI2 alloys in the form of thick films were prepared on a glass substrate using the conventional one-step chemical deposition method. The studies of the structural properties of these films showed that they have a very complex crystal structure, where PbI2 microcrystallites of micron and submicron sizes, as well as small nanoclusters (NCLs), are randomly formed in the CdI2 crystal matrix. It was found that the films show intense photo- and cathodoluminescence at room temperature. The temperature dependence of PL spectra of thick PbCdI2 films was studied. The nature of various radiative recombination processes in PbCdI2 films was established and it was shown that their PL spectra at room temperature are equally determined both by surface states in small PbI2 NCLs and by intrinsic defects in microcrystallites. The obtained PbCdI2 thick films can be considered as novel promising semiconductor materials for the development of effective inexpensive scintillator detectors for biomedical and industrial applications. [ABSTRACT FROM AUTHOR]

Identifying the mechanisms driving the distribution and diversity of parasitic organisms and characterizing the structure of parasite assemblages are critical to understanding host–parasite evolution, community dynamics, and disease transmission risk. Haemosporidian parasites of the genera Plasmodium and Haemoproteus are a diverse and cosmopolitan group of bird pathogens. Despite their global distribution, the ecological and historical factors shaping the diversity and distribution of these protozoan parasites across avian communities and geographic regions remain unclear. Here we used a region of the mitochondrial cytochrome b gene to characterize the diversity, biogeographical patterns, and phylogenetic relationships of Plasmodium and Haemoproteus infecting Amazonian birds. Specifically, we asked whether, and how, host community similarity and geography (latitude and area of endemism) structure parasite assemblages across 15 avian communities in the Amazon Basin. We identified 265 lineages of haemosporidians recovered from 2661 sampled birds from 330 species. Infection prevalence varied widely among host species, avian communities, areas of endemism, and latitude. Composition analysis demonstrated that both malarial parasites and host communities differed across areas of endemism and as a function of latitude. Thus, areas with similar avian community composition were similar in their parasite communities. Our analyses, within a regional biogeographic context, imply that host switching is the main event promoting diversification in malarial parasites. Although dispersal of haemosporidian parasites was constrained across six areas of endemism, these pathogens are not dispersal‐limited among communities within the same area of endemism. Our findings indicate that the distribution of malarial parasites in Amazonian birds is largely dependent on local ecological conditions and host evolutionary relationships. [ABSTRACT FROM AUTHOR]

Exosomes, nano-sized secreted extracellular vesicles (EVs), are actively studied for their diagnostic and therapeutic potential. In particular, exosomes secreted by dendritic cells ( DCs) have been shown to carry MHC-peptide complexes allowing efficient activation of T lymphocytes, thus displaying potential as promoters of adaptive immune responses. DCs also secrete other types of EVs of different size, subcellular origin and protein composition, whose immune capacities have not been yet compared to those of exosomes. Here, we show that large EVs ( lEVs) released by human DCs are as efficient as small EVs ( sEVs), including exosomes, to induce CD4+ T-cell activation in vitro. When released by immature DCs, however, lEVs and sEVs differ in their capacity to orient T helper (Th) cell responses, the former favouring secretion of Th2 cytokines, whereas the latter promote Th1 cytokine secretion ( IFN-γ). Upon DC maturation, however, these functional differences are abolished, and all EVs become able to induce IFN-γ. Our results highlight the need to comprehensively compare the functionalities of EV subtypes in all patho/physiological systems where exosomes are claimed to perform critical roles. [ABSTRACT FROM AUTHOR]

Purpose: To demonstrate that ultrashort echo time (UTE) magnetic resonance imaging (MRI) can achieve computed tomography (CT)-like quantification of lung parenchyma in free-breathing, non-sedated neonates. Because infant CTs are used sparingly, parenchymal disease evaluation via UTE MRI has potential for translational impact.Materials and Methods: Two neonatal control cohorts without suspected pulmonary morbidities underwent either a research UTE MRI (n = 5; 1.5T) or a clinically-ordered CT (n = 9). Whole-lung means and anterior-posterior gradients of UTE-measured image intensity (arbitrary units, au, normalized to muscle) and CT-measured density (g/cm3 ) were compared (Mann-Whitney U-test). Separately, a diseased neonatal cohort (n = 5) with various pulmonary morbidities underwent both UTE MRI and CT. UTE intensity and CT density were compared with Spearman correlations within ∼33 anatomically matched regions of interest (ROIs) in each diseased subject, spanning low- to high-density tissues. Radiological classifications were evaluated in all ROIs, with mean UTE intensities and CT densities compared in each classification.Results: In control subjects, whole-lung UTE intensities (0.51 ± 0.04 au) were similar to CT densities (0.44 ± 0.09 g/cm3 ) (P = 0.062), as were UTE (0.021 ± 0.020 au/cm) and CT (0.034 ± 0.024 [g/cm3 ]/cm) anterior-posterior gradients (P = 0.351). In diseased subjects' ROIs, significant correlations were observed between UTE and CT (P ≤0.007 in each case). Relative differences between UTE and CT were small in all classifications (4-25%).Conclusion: These results demonstrate a strong association between UTE image intensity and CT density, both between whole-lung tissue in control patients and regional radiological pathologies in diseased patients. This indicates the potential for UTE MRI to longitudinally evaluate neonatal pulmonary disease and to provide visualization of pathologies similar to CT, without sedation/anesthesia or ionizing radiation.Level Of Evidence: 3 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2017;46:992-1000. [ABSTRACT FROM AUTHOR]

Aim Geologically dynamic areas often harbour remarkable levels of biodiversity. Among other factors, mountain building is assumed to be a precondition for species radiation, and yet, the potential role of immigration as a source of biodiversity prior to radiation is often neglected. Here, we studied the biogeographical history of the large genus Saxifraga to unravel the role played by the Qinghai-Tibet Plateau ( QTP) for the diversification of this genus and to understand factors that have led to the establishment of high biodiversity in and around this region. Location QTP and surrounding mountain ranges and worldwide distribution range of Saxifraga. Methods Using a total of 420 taxa (321 ingroup taxa) comprising more than 60% of extant Saxifraga species, we studied the evolutionary history of Saxifraga by performing phylogenetic analyses (maximum likelihood and Bayesian inference on nuclear ITS and plastid trnL- trnF, matK sequences), divergence time estimation (using uncorrelated log-normal clock models and four fossil constraints in beast) and ancestral range estimation (using BioGeo BEARS). Results Saxifraga originated in North America around 74 (64-83) Ma, dispersed to South America and northern Asia during its early diversification and colonized Europe and the QTP region by the Late Eocene. The QTP region was colonized several times independently, followed in some lineages by rapid radiations, temporally coinciding with recent uplifts of the Hengduan Mountains at the southeastern fringe of the QTP. Subsequently, several lineages dispersed out of Tibet. Main conclusions Immigration, recent rapid radiation and lineage persistence were all important processes for the establishment of a rich species stock of Saxifraga in the QTP region. Because floristic exchanges between the neighbouring areas and the QTP region were bi-directional, the spatio-temporal evolution of Saxifraga contrasts with the 'out of QTP' pattern, which has often been assumed for northern temperate plants. [ABSTRACT FROM AUTHOR]

Purpose To implement pulmonary three-dimensional (3D) radial ultrashort echo-time (UTE) MRI in non-sedated, free-breathing neonates and adults with retrospective motion tracking of respiratory and intermittent bulk motion, to obtain diagnostic-quality, respiratory-gated images. Methods Pulmonary 3D radial UTE MRI was performed at 1.5 tesla (T) during free breathing in neonates and adult volunteers for validation. Motion-tracking waveforms were obtained from the time course of each free induction decay's initial point (i.e., k-space center), allowing for respiratory-gated image reconstructions that excluded data acquired during bulk motion. Tidal volumes were calculated from end-expiration and end-inspiration images. Respiratory rates were calculated from the Fourier transform of the motion-tracking waveform during quiet breathing, with comparison to physiologic prediction in neonates and validation with spirometry in adults. Results High-quality respiratory-gated anatomic images were obtained at inspiration and expiration, with less respiratory blurring at the expense of signal-to-noise for narrower gating windows. Inspiration-expiration volume differences agreed with physiologic predictions (neonates; Bland-Altman bias = 6.2 mL) and spirometric values (adults; bias = 0.11 L). MRI-measured respiratory rates compared well with the observed rates (biases = −0.5 and 0.2 breaths/min for neonates and adults, respectively). Conclusions Three-dimensional radial pulmonary UTE MRI allows for retrospective respiratory self-gating and removal of intermittent bulk motion in free-breathing, non-sedated neonates and adults. Magn Reson Med 77:1284-1295, 2017. © 2016 International Society for Magnetic Resonance in Medicine [ABSTRACT FROM AUTHOR]