bluuebunny/crossref_metadata_2025 huggingface dataset:
Research status and development trend of ceramifiable silicone rubber composites: a brief review
Authors: Li Jianhua
Published: December 2021

Ceramifiable silicone rubber composites (CSR) are one of the most important industrially produced elastic technical materials. At present, there is a strong demand for CSR in the high-tech fields of high-speed rail, nuclear power, rocket and aerospace, which are still to be met. Many scholars have committed to the research work of improving the thermal stability, flame retardant, mechanical properties by changing the silicone rubber (SR) matrixes and filler, tremendous advances in CSR have been made for over the last decades where CSR intended for the high technology fields has evolved through different generations. In summary, the first-generation research is based on matrix reaction, the second-generation research is on reaction products, and the third-generation research is on fillers effects. In this review, the evolution of CSR and the synthesis routes, reaction mechanism, and degradation mechanism are introduced and analyzed; fillers, various types of CSR based composites as well as the flame retardancy and mechanical properties are reviewed. Finally, the problems of developing high-performance CSRs are proposed and discussed. This review provides a theoretical basis and supporting data for the application of high-performance CSR, as well as provides details on the fire prevention mechanism of CSR.
Study of the temperature dependence of a carbidized layer formation on the tungsten surface under plasma irradiation
Authors: Baklanov Victor , Zhanbolatova Gainiya , Skakov Mazhyn , Miniyazov Arman , Sokolov Igor , Tulenbergenov Timur , Kozhakhmetov Yernat , Bukina Olga , Orazgaliev Nurkhat
Published: December 2021

The paper considers a method of tungsten surface carbidization using a beam-plasma discharge (BPD), which was implemented in a plasma-beam installation (PBI). The advantage of this method is to create conditions for chemical reactions and physical processes as close as possible to those possible in thermonuclear installations. The BPD makes it possible to generate plasma using different working gases. Methane was used as a plasma-forming gas. The working gas pressure in a chamber was (1,3–1,4)·10–1 Pa. The temperature dependence of the carbidized layer formation on the tungsten surface under plasma irradiation was determined in the temperature range of 700 °C–1700 °C. The formation of tungsten carbides in surface layers was confirmed by SEM and x-ray diffraction analysis. It was found that interaction between tungsten and methane in a wide temperature range can proceed with simultaneous or sequential formation of the carbide phases W2C and WC.
Effects of particle grading composition of SiC on properties of silicon-bonded SiC porous ceramics
Authors: Zhao Changzhi , Hu Huajian , Zhuo Meizhen , Shen Chunying
Published: December 2021

Silicon-bonded silicon carbide (SBSC) porous ceramics had been prepared by mixing two different particle size of SiC powder (coarse and fine) as aggregates for silicon carbide porous ceramics, adding metallic Si as the binder phase and firing at 1450 °C under argon atmosphere. Various combinations of SiC mixtures consisting of two different particle size and packing density were prepared, and the samples were investigated to understand apparent porosity, bending strength, pore size distribution, and microstructure. The result showed that mixing an appropriate proportion of SiC coarse and fine powders could not only improve the pore size distribution of SBSC porous ceramics but also significantly increase the bending strength compared with the single-particle size sample. The system had the highest free packing density when the ratio of coarse to fine SiC size was >2 and the coarse powder content was 60–70 wt%. The optimal bending strength, and apparent porosity were 37.53 MPa and 37.11% respectively when mixing 70 wt% of coarse powder (50.8 μm) and 30 wt% of fine powder (9.5 μm) and sintered at 1450 °C in an argon atmosphere. The material created had 100.3% increased bending strength, and 0.99% decreased porosity compared with the single-particle size sample (50.8 μm).
SIGNORApp: a Cytoscape 3 application to access SIGNOR data
Authors: De Marinis Ilaria , Lo Surdo Prisca , Cesareni Gianni , Perfetto Livia
Published: December 2021

SIGNORApp is a Cytoscape 3 (3.8 and later) application that provides access to causal interactions annotated in the SIGNOR resource. The application builds networks that can be represented as weighted, signed, directed graphs, where nodes are interacting biological entities and edges represent causal interactions captured by expert curators from experiments reported in peer reviewed journals. Users can query the SIGNOR dataset with (i) single or multiple entity name(s) or identifier(s) and optionally they may require to include in the output network their interacting partners, (ii) browse pathways that are annotated in the SIGNOR resource and (iii) extract the entire causal interactome. The app offers two visualizations modes: one only displaying entity interactions and a second emphasizing the post-translational modifications occurring as a consequence of the interaction. In addition, users can click on nodes and edges to access entity and interaction annotations. Causal information is available for three model organisms: Homo sapiens, Mus musculus and Rattus norvegicus.

Availability and implementation

SIGNORApp has been developed for Cytoscape 3 (3.8 and later) in the Java programming language. The latest source code and the plugin can be found at: https://github.com/SIGNORcysAPP/signor-app and https://apps.cytoscape.org/apps/signorapp, respectively.

Supplementary information

Supplementary data are available at Bioinformatics online.
Bi-allelic loss-of-function OBSCN variants predispose individuals to severe recurrent rhabdomyolysis
Authors: Cabrera-Serrano Macarena , Caccavelli Laure , Savarese Marco , Vihola Anna , Jokela Manu , Johari Mridul , Capiod Thierry , Madrange Marine , Bugiardini Enrico , Brady Stefen , Quinlivan Rosaline , Merve Ashirwad , Scalco Renata , Hilton-Jones David , Houlden Henry , Aydin Halil Ibrahim , Ceylaner Serdar , Drewes Sarah , Vockley Jerry , Taylor Rhonda L , Folland Chiara , Kelly Aasta , Goullee Hayley , Ylikallio Emil , Auranen Mari , Tyynismaa Henna , Udd Bjarne , Forrest Alistair R R , Davis Mark R , Bratkovic Drago , Manton Nicholas , Robertson Thomas , O’Gorman Cullen , McCombe Pamela , Laing Nigel G , Phillips Liza , de Lonlay Pascale , Ravenscroft Gianina
Published: December 2021

Rhabdomyolysis is the acute breakdown of skeletal myofibres in response to an initiating factor, most commonly toxins and over exertion. A variety of genetic disorders predispose to rhabdomyolysis through different pathogenic mechanisms, particularly in patients with recurrent episodes. However, most cases remain without a genetic diagnosis.

Here we present six patients who presented with severe and recurrent rhabdomyolysis, usually with onset in the teenage years; other features included a history of myalgia and muscle cramps. We identified 10 bi-allelic loss-of-function variants in the gene encoding obscurin (OBSCN) predisposing individuals to recurrent rhabdomyolysis. We show reduced expression of OBSCN and loss of obscurin protein in patient muscle. Obscurin is proposed to be involved in sarcoplasmic reticulum function and Ca2+ handling. Patient cultured myoblasts appear more susceptible to starvation as evidenced by a greater decreased in sarcoplasmic reticulum Ca2+ content compared to control myoblasts. This likely reflects a lower efficiency when pumping Ca2+ back into the sarcoplasmic reticulum and/or a decrease in Ca2+ sarcoplasmic reticulum storage ability when metabolism is diminished. OSBCN variants have previously been associated with cardiomyopathies. None of the patients presented with a cardiomyopathy and cardiac examinations were normal in all cases in which cardiac function was assessed. There was also no history of cardiomyopathy in first degree relatives, in particular in any of the carrier parents.

This cohort is relatively young, thus follow-up studies and the identification of additional cases with bi-allelic null OBSCN variants will further delineate OBSCN-related disease and the clinical course of disease.
Weight Gain of Spodoptera frugiperda Larvae (Lepidoptera: Noctuidae) on Leaf and Floral Tissues of Silphium integrifolium (Asterales: Asteraceae) Differs by Plant Genotype
Authors: Peterson Kelsey , Cheremond Edy , Brandvain Yaniv , Van Tassel David , Murrell Ebony
Published: December 2021

Silflower (Silphium integrifolium (Michaux)) is a native North American relative of sunflower that is undergoing domestication as a perennial oilseed crop. As silflower incurs pest damage from multiple insect species, it is necessary to screen genotypes for their effect on insect performance such that more pest tolerant/resistant accessions can be incorporated into future silflower breeding programs. We present a bioassay protocol for silflower using the generalist herbivore fall armyworm (Spodoptera frugiperda (J. E. Smith)). In this study, fall armyworm larvae were placed on leaf and flower tissue from eleven silflower genotypes, one cup plant (Silphium perfoliatum (L.) (Asterales: Asteraceae)) genotype, and an inbred sunflower line (Helianthus annuus (L.) (Asterales: Asteraceae), HA89). Caterpillar weight gained during a 4-d feeding period significantly differed on leaf and floral tissue from different silflower genotypes, between the Silphium species (silflower and cup plant), and between Silphium genotypes and annual sunflower. Two wild silflower genotypes produced lower larval weight gain on both the floral and leaf tissue than all other genotypes, suggesting these genotypes have either lower nutrition or greater resistance to fall armyworm. However, nonsignificant correlations between larval growth on floral versus leaf tissue across all plant species tested and among all silflower accessions suggest insect performances on these tissue types in silflower are independent. Along with identifying germplasm of interest for silflower breeding programs, we established an easily replicable bioassay protocol using fall armyworm on silflower floral and leaf tissues.
Drosophila centrocortin is dispensable for centriole duplication but contributes to centrosome separation
Authors: Mehta Dipen S , Zein-Sabatto Hala , Ryder Pearl V , Lee Jina , Lerit Dorothy A
Published: December 2021

Centrosomes are microtubule-organizing centers that duplicate exactly once to organize the bipolar mitotic spindle required for error-free mitosis. Prior work indicated that Drosophila centrocortin (cen) is required for normal centrosome separation, although a role in centriole duplication was not closely examined. Through time-lapse recordings of rapid syncytial divisions, we monitored centriole duplication and the kinetics of centrosome separation in control vs cen null embryos. Our data suggest that although cen is dispensable for centriole duplication, it contributes to centrosome separation.
A sensitized genetic screen to identify regulators of Caenorhabditis elegans germline stem cells
Authors: Robinson-Thiewes Sarah , Kershner Aaron M , Shin Heaji , Haupt Kimberly A , Kroll-Connor Peggy , Kimble Judith
Published: December 2021

GLP-1/Notch signaling and a downstream RNA regulatory network maintain germline stem cells in Caenorhabditis elegans. In mutants lacking the GLP-1 receptor, all germline stem cells enter the meiotic cell cycle precociously and differentiate into sperm. This dramatic germline stem cell defect is called the “Glp” phenotype. The lst-1 and sygl-1 genes are direct targets of Notch transcriptional activation and functionally redundant. Whereas single lst-1 and sygl-1 mutants are fertile, lst-1 sygl-1 double mutants are sterile with a Glp phenotype. We set out to identify genes that function redundantly with either lst-1 or sygl-1 to maintain germline stem cells. To this end, we conducted forward genetic screens for mutants with a Glp phenotype in genetic backgrounds lacking functional copies of either lst-1 or sygl-1. The screens generated 9 glp-1 alleles, 2 lst-1 alleles, and 1 allele of pole-1, which encodes the catalytic subunit of DNA polymerase ε. Three glp-1 alleles reside in Ankyrin repeats not previously mutated. pole-1 single mutants have a low penetrance Glp phenotype that is enhanced by loss of sygl-1. Thus, the screen uncovered 1 locus that interacts genetically with sygl-1 and generated useful mutations for further studies of germline stem cell regulation.
Human-Centered Design of an Advance Care Planning Group Visit for Mild Cognitive Impairment
Authors: Daddato Andrea E , Staton Elizabeth W , Bettcher Brianne M , Shanbhag Prajakta , Lum Hillary D
Published: December 2021

Background and Objectives

While advance care planning (ACP) is critical for ensuring optimal end-of-life outcomes among individuals with mild cognitive impairment (MCI), many individuals who may benefit from ACP have not initiated this process. This article aims to describe the iterative design of an MCI group visit-based intervention and evaluate the feasibility and acceptability of the intervention.

Research Design and Methods

We used human-centered design, rapid-cycle prototyping, and multiple methods to adapt an ENgaging in Advance Care planning Talks (ENACT) Group Visits intervention. We convened an advisory panel of persons with MCI and care partners (n = 6 dyads) to refine the intervention and conducted a single-arm pilot of 4 MCI ENACT intervention prototypes (n = 13 dyads). We used surveys and interviews to assess outcomes from multiple perspectives.

Results

The advisory panel affirmed that ACP is a priority for individuals with MCI, described the need for ACP in a group setting, and suggested refinements to ACP resources for the MCI ENACT intervention. Feasibility of recruitment was limited. MCI ENACT intervention participants strongly agreed that group discussions provided useful information and recommended the intervention. Themes supporting acceptability included (a) feedback on acceptability of the intervention, (b) previous experiences with ACP, and (c) reasons for participation, including desire for discussions about MCI and how it relates to ACP.

Discussion and Implications

Despite stakeholders’ positive ratings of acceptability of the MCI ENACT intervention, future work is needed to enhance the feasibility of recruitment to support implementation into clinical settings.
Effects of the 2014 Affordable Care Act Medicaid Expansions on Health Care Access and Health Status of Poor Adults Aged 60–64 Years: Evidence From the First 6 Years
Authors: Bin Abdul Baten Redwan , Wehby George L
Published: December 2021

Background and Objectives

Little is known on the effects of the Affordable Care Act (ACA) Medicaid expansions on health care access and health status of adults closest to 65. This study examines the effects of ACA Medicaid expansion on access and health status of poor adults aged 60–64 years.

Research Design and Methods

The study employs a difference-in-differences design comparing states that expanded Medicaid in 2014 under the ACA and nonexpansion states over 6 years postexpansion. The data are from the 2011–2019 Behavioral Risk Factor Surveillance System for individuals aged 60–64 years below the Federal Poverty Level.

Results

Having any health care coverage rate increased by 8.5 percentage points (p < .01), while the rate of forgoing a needed doctor’s visit due to cost declined by 6.6 percentage points (p < .01). Similarly, rates of having a personal doctor/provider and completing a routine checkup increased by 9.1 (p < .01) and 4.8 (p < .1) percentage points, respectively. Moreover, days not in good physical health in the past 30 declined by 1.5 days (p < .05), with suggestive evidence for decline in days not in good mental health and improvement in self-rated health.

Discussion and Implications

The ACA Medicaid expansions have improved health care access and health status of poor adults aged 60–64 years. Expanding Medicaid in the states that have not yet done so would reduce barriers to care and address unmet health needs for this population. Bridging coverage for individuals aged 60–64 years by lowering Medicare eligibility age could have long-term effects on well-being and health services utilization.
Transcriptome-wide association study identifies multiple genes and pathways associated with thyroid function
Authors: Ke Xin , Tian Xin , Yao Shi , Wu Hao , Duan Yuan-Yuan , Wang Nai-Ning , Shi Wei , Yang Tie-Lin , Dong Shan-Shan , Huang Dageng , Guo Yan
Published: December 2021

Thyroid dysfunction is a common endocrine disease measured by thyroid-stimulating hormone (TSH) level. Although >70 genetic loci associated with TSH have been reported through genome-wide association studies (GWASs), the variants can only explain a small fraction of the thyroid function heritability. To identify novel candidate genes for thyroid function, we conducted the first large-scale transcriptome-wide association study (TWAS) for thyroid function using GWAS-summary data for TSH levels in up to 119 715 individuals combined with precomputed gene expression weights of six panels from four tissue types. The candidate genes identified by TWAS were further validated by TWAS replication and gene expression profiles. We identified 74 conditionally independent genes significantly associated with thyroid function, such as PDE8B (P = 1.67 × 10−282), PDE10A (P = 7.61 × 10−119), NR3C2 (P = 1.50 × 10−92) and CAPZB (P = 3.13 × 10−79). After TWAS replication using UKBB datasets, 26 genes were replicated for significant associations with thyroid-relevant diseases/traits. Among them, 16 genes were causal for their associations to thyroid-relevant diseases/traits and further validated in differential expression analyses, including two novel genes (MFSD6 and RBM47) that did not implicate in previous GWASs. Enrichment analyses detected several pathways associated with thyroid function, such as the cAMP signaling pathway (P = 7.27 × 10−4), hemostasis (P = 3.74 × 10−4), and platelet activation, signaling and aggregation (P = 9.98 × 10−4). Our study identified multiple candidate genes and pathways associated with thyroid function, providing novel clues for revealing the genetic mechanisms of thyroid function and disease.
SARS-CoV-2 Infection During Pregnancy and Associated Perinatal Health Outcomes: A National US Cohort Study
Authors: Regan Annette K , Arah Onyebuchi A , Fell Deshayne B , Sullivan Sheena G
Published: December 2021

Background

Although severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection has been associated with increased risk of adverse perinatal health outcomes, few large-scale, community-based epidemiological studies have been conducted.

Methods

We conducted a national cohort study using deidentified administrative claims data for 78 283 pregnancies with estimated conception before 30 April 2020 and pregnancy end after 11 March 2020. We identified SARS-CoV-2 infections using diagnostic and laboratory testing data, and compared the risk of pregnancy outcomes using Cox proportional hazard models treating coronavirus disease 2019 (COVID-19) as a time-varying exposure and adjusting for baseline covariates.

Results

Of the pregnancies, 2655 (3.4%) had a documented SARS-CoV-2 infection. COVID-19 during pregnancy was not associated with risk of miscarriage, antepartum hemorrhage, or stillbirth, but was associated with 2–3 fold higher risk of induced abortion (adjusted hazard ratio [aHR], 2.60; 95% confidence interval [CI], 1.17–5.78), cesarean delivery (aHR, 1.99; 95% CI, 1.71–2.31), clinician-initiated preterm birth (aHR, 2.88; 95% CI, 1.93–4.30), spontaneous preterm birth (aHR, 1.79; 95% CI, 1.37–2.34), and fetal growth restriction (aHR, 2.04; 95% CI, 1.72–2.43).

Conclusions

Prenatal SARS-CoV-2 infection was associated with increased risk of adverse pregnancy outcomes. Prevention could have fetal health benefits.
The enforcement of cross-border competition law claims in Asia-pacific and choice of forum agreements: private litigation or arbitration?
Authors: Nishioka Kazuaki
Published: December 2021

A private plaintiff may bring an action against a defendant for the infringement of competition law. In Western countries, it is widely accepted that parties can subject to choice of forum agreements claims seeking private law remedies based on competition law infringements. Accordingly, parties are free to refer those claims to a foreign court or arbitral tribunal for their determination. In contrast, it remains an open question in most Asia-Pacific jurisdictions whether competition-related claims are subject to choice of forum agreements (in particular, an arbitration agreement). If the answer is affirmative, a number of incidental questions will arise. For instance, in what kinds of competition-related claims and under what circumstances will choice of forum agreements be applicable? With focus on international arbitration, this article will look into recent developments around the globe and then propose how states in the Asia-Pacific region should approach those issues.
IGA-PD penalty-based coupling for immersed air-blast fluid–structure interaction: a simple and effective solution for fracture and fragmentation
Authors: Behzadinasab Masoud , Hillman Michael , Bazilevs Yuri
Published: December 2021

We present a novel formulation for the immersed coupling of isogeometric analysis and peridynamics for the simulation of fluid–structure interaction (FSI). We focus on air-blast FSI and address the computational challenges of immersed FSI methods in the simulation of fracture and fragmentation by developing a weakly volume-coupled FSI formulation by means of a simple penalty approach. We show the mathematical formulation and present several numerical examples of inelastic ductile and brittle solids under blast loading that clearly demonstrate the power and robustness of the proposed methodology.
Prospects of discovering subsolar primordial black holes using the stochastic gravitational wave background from third-generation detectors
Authors: Mukherjee Suvodip , Meinema Matthew S P , Silk Joseph
Published: December 2021

Primordial black holes (PBHs) are dark matter candidates that span broad mass ranges from 10−17 M⊙ to ∼100 M⊙. We show that the stochastic gravitational wave background can be a powerful window for the detection of subsolar mass PBHs and shed light on their formation channel via third-generation gravitational wave detectors such as Cosmic Explorer and the Einstein Telescope. By using the mass distribution of the compact objects and the redshift evolution of the merger rates, we can distinguish astrophysical sources from PBHs and will be able to constrain the fraction of subsolar mass PBHs ≤1 M⊙ in the form of dark matter $f_\mathrm{PBH}\le 1{{\ \rm per\ cent}}$ at $68{{\ \rm per\ cent}}$ C.L. even for a pessimistic value of a binary suppression factor. In the absence of any suppression of the merger rate, constraints on fPBH will be less than $0.001{{\ \rm per\ cent}}$. Furthermore, we will be able to measure the redshift evolution of the PBH merger rate with about $1{{\ \rm per\ cent}}$ accuracy, making it possible to uniquely distinguish between the Poisson and clustered PBH scenarios.
Detection of 7Be ii in the Small Magellanic Cloud
Authors: Izzo Luca , Molaro Paolo , Cescutti Gabriele , Aydi Elias , Selvelli Pierluigi , Harvey Eamonn , Agnello Adriano , Bonifacio Piercarlo , Della Valle Massimo , Guido Ernesto , Hernanz Margarita
Published: December 2021

We analyse high-resolution spectra of two classical novae that exploded in the Small Magellanic Cloud (SMC). 7Be ii resonance transitions are detected in both ASASSN-19qv and ASASSN-20ni novae. This is the first detection outside the Galaxy and confirms that thermo-nuclear runaway reactions, leading to the 7Be formation, are effective also in the low-metallicity regime, characteristic of the SMC. Derived yields are of N(7Be = 7Li)/N(H)  = (5.3 ± 0.2) × 10−6 which are a factor 4 lower than the typical values of the Galaxy. Inspection of two historical novae in the Large Magellanic Cloud observed with IUE in 1991 and 1992 showed also the possible presence of 7Be and similar yields. For an ejecta of MH, ej = 10−5 M⊙, the amount of 7Li produced is of $M_{^7 Li} = (3.7 \pm 0.6) \times 10^{-10}$ M⊙ per nova event. Detailed chemical evolutionary model for the SMC shows that novae could have made an amount of lithium in the SMC corresponding to a fractional abundance of A(Li) ≈ 2.6. Therefore, it is argued that a comparison with the abundance of Li in the SMC, as measured by its interstellar medium, could effectively constrain the amount of the initial abundance of primordial Li, which is currently controversial.
Optical solution to spot elongation in laser guide stars wavefront sensors for Extremely Large Telescopes
Authors: Lombini Matteo , Schreiber Laura , Diolaiti Emiliano , Cortecchia Fausto
Published: December 2021

Laser guide stars have been proposed to overcome a widely recognized limitation of adaptive optics: the need for bright reference sources for wavefront sensing nearby the scientific field of interest. The laser guide stars foreseen for the future Extremely Large Telescopes are based on the resonant back-scattering of a laser beam by the Sodium atoms concentrated in a ∼13 km thick layer at about 90 km above the ground. Such an artificial source, observed from a position laterally offset from the laser projector, appears elongated due to the finite thickness of the Sodium layer: on a 40-m class telescope with laser projector located on the primary mirror edge the image elongation may exceed 13 arcsec. In a Shack–Hartmann wavefront sensor, the elongated spots require the use of large detectors to avoid spot truncation and impose demanding requirements in terms of photon flux return with respect to smaller telescopes. We propose an alternative wavefront sensor concept intrinsically insensitive to the spot elongation, measuring the local wavefront slope in the direction orthogonal to the elongation itself; the full 2D slope measurements are retrieved by combining the signals from different laser guide stars, projected from different positions at the edge of the telescope. The performance of the new wavefront sensor is analysed in the framework of a ground-layer adaptive optics application. A possible extension to multiconjugate adaptive optics is also qualitatively described.
Effects of pebble accretion on the growth and composition of planetesimals in the inner Solar system
Authors: Mah J , Brasser R , Bouvier A , Mojzsis S J
Published: December 2021

Recent work has shown that aside from the classical view of collisions by increasingly massive planetesimals, the accretion of mm to m-sized ‘pebbles’ can also reproduce the mass–orbit distribution of the terrestrial planets. Here, we perform N-body simulations to study the effects of pebble accretion on to growing planetesimals of different diameters located in the inner Solar system. The simulations are run to occur during the lifetime of the gas disc while also simultaneously taking Jupiter’s growth into account. We find that pebble accretion can increase the mass in the solid disc by at least a few times its initial mass with reasonable assumptions that pebbles fragment to smaller sized grains at the snow line and that gas-disc-induced orbital migration effects are in force. Such a large contribution in mass by pebbles would seem to imply that the isotopic composition of the inner Solar system should be similar to the pebble source (i.e. outer Solar system). This implication appears to violate the observed nucleosynthetic isotopic dichotomy of the sampled Solar system. Thus, pebble accretion played little or no role in terrestrial planet formation.
Untangling magnetic massive star properties with linear polarization variability and the analytic dynamical magnetosphere model
Authors: Munoz M S , Wade G A , Faes D M , Carciofi A C , Labadie-Bartz J
Published: December 2021

Light scattered off particles can become linearly polarized. Stars surrounded by oblique, co-rotating envelopes are therefore expected to manifest periodic linear polarimetric variations. The electron scattering magnetospheres of magnetic massive stars are expected to be suitable candidates to observe this effect. In this paper, we present the first semi-analytical model capable of synthesizing the continuum polarimetric signatures of magnetic O-type stars in an optically thin, single electron scattering limit. The purpose of this investigation is to improve our general understanding of magnetic hot stars by characterizing their polarimetric behaviour. Our linear polarization model is constructed by combining the analytical expressions for the polarimetric variations of an obliquely rotating envelope with the analytic dynamical magnetosphere model to represent a physical model for the envelope density structure. We compute grids of model Stokes Q and U curves and show that their shapes are unique to the choice of inclination and obliquity angles. We apply our model to HD 191612, a prototypical Of?p-type star, having both polarimetric and photometric observations. We find that the polarimetric modulations are best reproduced with $i=19^{+12}_{-3}$○, $\beta =71^{+3}_{-9}$○, and $\log \dot{M}_{B=0}=-6.11^{+0.12}_{-0.06}$ [M⊙ yr−1]. These results agree with previous investigations of this star. By combining both polarimetric and photometric synthesis tools, we simultaneously model the observations thus adding further refinement of the wind and magnetic properties of HD 191612.
Dynamics of irregularly shaped cometary particles subjected to outflowing gas and solar radiative forces and torques
Authors: Moreno Fernando , Guirado Daniel , Muñoz Olga , Zakharov Vladimir , Ivanovski Stavro , Fulle Marco , Rotundi Alessandra , Frattin Elisa , Bertini Ivano
Published: December 2021

The dynamics of irregularly shaped particles subjected to the combined effect of gas drag and radiative forces and torques in a cometary environment is investigated. The equations of motion are integrated over distances from the nucleus surface up to distances where the gas drag is negligible. The aerodynamic forces and torques are computed assuming a spherically symmetric expanding gas. The calculations are limited to particle sizes in the geometric optics limit, which is the range of validity of our radiative torque calculations. The dynamical behaviour of irregular particles is quite different to those exhibited by non-spherical but symmetric particles such as spheroids. An application of the dynamical model to comet 67P/Churyumov–Gerasimenko, the target of the Rosetta mission, is made. We found that, for particle sizes larger than ∼10 μm, the radiative torques are negligible in comparison with the gas-driven torques up to a distance of ∼100 km from the nucleus surface. The rotation frequencies of the particles depend on their size, shape, and the heliocentric distance, while the terminal velocities, being also dependent on size and heliocentric distance, show only a very weak dependence on particle shape. The ratio of the sum of the particles projected areas in the sun-to-comet direction to that of the sum of the particles projected areas in any direction perpendicular to it is nearly unity, indicating that the interpretation of the observed u-shaped scattering phase function by Rosetta/OSIRIS on comet 67P coma cannot be linked to mechanical alignment of the particles.
Crystal structures of alphavirus nonstructural protein 4 (nsP4) reveal an intrinsically dynamic RNA-dependent RNA polymerase fold
Authors: Tan Yaw Bia , Lello Laura Sandra , Liu Xin , Law Yee-Song , Kang Congbao , Lescar Julien , Zheng Jie , Merits Andres , Luo Dahai
Published: December 2021

Alphaviruses such as Ross River virus (RRV), chikungunya virus (CHIKV), Sindbis virus (SINV), and Venezuelan equine encephalitis virus (VEEV) are mosquito-borne pathogens that can cause arthritis or encephalitis diseases. Nonstructural protein 4 (nsP4) of alphaviruses possesses RNA-dependent RNA polymerase (RdRp) activity essential for viral RNA replication. No 3D structure has been available for nsP4 of any alphaviruses despite its importance for understanding alphaviral RNA replication and for the design of antiviral drugs. Here, we report crystal structures of the RdRp domain of nsP4 from both RRV and SINV determined at resolutions of 2.6 Å and 1.9 Å. The structure of the alphavirus RdRp domain appears most closely related to RdRps from pestiviruses, noroviruses, and picornaviruses. Hydrogen-deuterium exchange mass spectrometry (HDX-MS) and nuclear magnetic resonance (NMR) methods showed that in solution, nsP4 is highly dynamic with an intrinsically disordered N-terminal domain. Both full-length nsP4 and the RdRp domain were capable to catalyze RNA polymerization. Structure-guided mutagenesis using a trans-replicase system identified nsP4 regions critical for viral RNA replication.
Correlates of children’s dietary intake in childcare settings: A systematic review
Authors: Hasnin Saima , Saltzman Jaclyn A , Dev Dipti A
Published: December 2021

Context

Children consume up to two-thirds of their daily dietary requirements in full-time childcare, making the setting a critical vector for preventing childhood obesity.

Objective

To summarize the ecological correlates of children’s dietary intake in childcare settings that were identified and categorized using the Six-Cs developmental ecological model of contributors to overweight and obesity in childhood.

Data Sources

A literature search was conducted in 4 electronic databases.

Study Selection

English-language, peer-reviewed publications that investigated at least 1 correlate of children’s (ages 2–6 years) dietary intake in childcare settings and measured children’s actual consumption of foods and beverages from food groups were included.

Data Extraction

Correlates were categorized into child, clan, community, and country groups.

Results

A total of 55 studies, which examined 29 correlates, were reviewed. Correlates identified included child’s age, sex, characteristics of food provision (namely, food composition, foods and beverages served, portion sizes), repeated exposure, nutrition education, book reading, peer influence, meal service type, and childcare teachers’ responsive feeding practices. Policies and participation in Head Start and the Child and Adult Care Food Program could not be determined as correlates of children’s dietary intake, owing to a lack of evidence.

Conclusion

This review produced a list of correlates to consider in designing interventions to improve children’s dietary intake in childcare settings. The correlates could contribute to development of lifelong healthy eating habits, thereby preventing childhood obesity.
Pre-exposure Prophylaxis Recent Adherence With Real-Time Adherence Feedback and Partner Human Immunodeficiency Virus Self-Testing: A Pilot Trial Among Postpartum Women
Authors: Joseph Davey Dvora Leah , Dovel Kathryn , Mvududu Rufaro , Nyemba Dorothy , Mashele Nyiko , Bekker Linda-Gail , Gorbach Pamina M , Coates Thomas J , Myer Landon
Published: December 2021

Background

Pre-exposure prophylaxis (PrEP) is safe and effective in postpartum women. Human immunodeficiency virus self-testing (HIVST) for male partners combined with biofeedback counseling through real-time adherence measures may improve PrEP use among postpartum women.

Methods

Between August 2020 and April 2021, we randomized postpartum women who initiated PrEP in pregnancy 1:1 to the intervention group (HIVST + biofeedback counseling after urine tenofovir test) or to standard of care ([SOC] facility-based human immunodeficiency virus [HIV] tests and routine counseling without biofeedback). The outcomes of interest were PrEP adherence in the past 48–72 hours via urine tenofovir tests and partner HIV testing, measured 1-month after randomization. Secondary outcomes included the proportion of partners who tested for HIV and the discrepancy between self-reported PrEP adherence and urine tenofovir result.

Results

We enrolled 106 women (median age = 26 years). At enrollment, 72% of women reported missing <2 doses in the past 7 days; 36% of women had tenofovir present in her urine. One month after enrollment, 62% (n = 33) of women in the intervention arm had tenofovir present in their urine compared to 34% (n = 18) in SOC (risk ratio [RR] = 1.83; 95% confidence interval [CI] = 1.19–2.82; P = .001). Two thirds of women in the intervention arm reported that her partner tested for HIV (66%; n = 35), compared to 17% (n = 9) in SOC (RR = 3.89; 95% CI = 2.08–7.27; P < .001). Self-reported PrEP adherence (took PrEP >5 of last week) with no tenofovir in urine test was lower in the intervention group (17% vs 46%; RR = 0.33; 95% CI = 0.17–0.67; P = .03). No social or clinical adverse events were reported in the intervention arm.

Conclusions

The HIVST for partners and biofeedback counseling increased levels of recent PrEP adherence, pointing to the importance of these interventions to support PrEP use in this population.
Risk of food insecurity in undocumented migrant households in Birmingham, UK
Authors: Jolly Andrew , Thompson Janice L
Published: December 2021

Background

This study aimed to understand the extent of household food insecurity amongst undocumented migrant families in Birmingham,UK.

Methods

Cross-sectional survey of households (n = 74) with dependent children using the USDA 18-item household food security (HFS) module. All households had an irregular immigration status and were accessing an immigration advice drop-in service (n = 98 adults; n = 138 children) in Birmingham.

Results

About 95.9% of households were food insecure, and 94.6% of children lived in households with low or very low food security. Food insecurity varied within households. Around 91.8% of adults were food insecure, compared to 75.6% of children. Spearman’s rank-order correlation indicated a statistically significant positive correlation between household food insecurity level and number of children (rho = 0.253, P = 0.031). A Kruskal–Wallis H Test indicated no statistically significant difference (P = 0.730) in HFS score between households supported by asylum support, children’s social services or paid employment in the informal economy and those that had no regular income.

Conclusions

Prevalence of HFS was higher in this sample of undocumented migrant households with dependent children in Birmingham, UK, than in the wider population, and larger households were more food insecure. Households without a regular income were no more likely to be food insecure than households with financial support.
China’s Model of Managing the Financial System
Authors: Brunnermeier Markus K , Sockin Michael , Xiong Wei
Published: December 2021

China’s economic model involves regular and intensive government interventions in financial markets, while Western policymakers often refrain from substantial interventions outside crisis periods. We develop a theoretical framework to rationalize the approaches of both China and the West to managing the financial system as being optimal given the differences in their respective economies. In this framework, a government leans against trading of noise traders but at the expense of introducing policy noise to the market. Our welfare analysis shows that under certain underlying economic conditions, the optimal government policy induces a government-centric equilibrium, in which government intervention is so intensive that all investors choose to acquire private information about policy noise rather than fundamentals. This policy regime characterizes China’s approach with financial stability prioritized over other policy objectives.
Genome-Wide Association Analysis of Resistance toPseudoperonospora cubensisin Citron Watermelon
Authors: Katuuramu Dennis N. , Branham Sandra E. , Levi Amnon , Wechter W. Patrick
Published: December 2021

Cultivated sweet watermelon (Citrullus lanatus) is an important vegetable crop for millions of people around the world. There are limited sources of resistance to economically important diseases within C. lanatus, whereas C. amarus has a reservoir of traits that can be exploited to improve C. lanatus for resistance to biotic and abiotic stresses. Cucurbit downy mildew (CDM), caused by Pseudoperonospora cubensis, is an emerging threat to watermelon production. We screened 122 C. amarus accessions for resistance to CDM over two tests (environments). The accessions were genotyped by whole-genome resequencing to generate 2,126,759 single nucleotide polymorphic (SNP) markers. A genome-wide association study was deployed to uncover marker-trait associations and identify candidate genes underlying resistance to CDM. Our results indicate the presence of wide phenotypic variability (1.1 to 57.8%) for leaf area infection, representing a 50.7-fold variation for CDM resistance across the C. amarus germplasm collection. Broad-sense heritability estimate was 0.55, implying the presence of moderate genetic effects for resistance to CDM. The peak SNP markers associated with resistance to P. cubensis were located on chromosomes Ca03, Ca05, Ca07, and Ca11. The significant SNP markers accounted for up to 30% of the phenotypic variation and were associated with promising candidate genes encoding leucine-rich repeat receptor-like protein kinase and the WRKY transcription factor. This information will be useful in understanding the genetic architecture of the P. cubensis−Citrullus spp. patho-system as well as development of resources for genomics-assisted breeding for resistance to CDM in watermelon.
Advances in and Prospects for Actinidia Viruses
Authors: Zhang Guoding , Bai Bixin , Xu Ming , Liu Yuling , Wu Yunfeng , Zhao Lei
Published: December 2021

Kiwifruit (Actinidia spp.) is an economically important fruit crop worldwide. Before 2010, kiwifruit viruses had not received much attention; since then, more than 20 viruses infecting kiwifruit have been discovered. Some of these viruses cause severe yellowing, mosaic, necrosis, ringspots, and other symptoms on leaves, seriously impacting yield and quality. Many of these viruses are widely distributed. This review summarizes recent research advances in the identification, genomic variation, distribution, transmission, detection, incidence, prevention, and control of kiwifruit viruses and proposes directions for future research. Using virus-tested propagation material is the most economical and effective method for controlling kiwifruit viruses.
PAs and NPs provide essential care for children with COVID-19
Authors: Westry Maria Fatima G. , Nakano Priscila E. , Arrington Amy S. , Graf Jeanine M.
Published: December 2021

The rapid spread of COVID-19 brought forth a rapid increase in hospitalization rates, requiring changes in hospital use and medical personnel structure. Physician assistants (PAs) and NPs in pediatric critical care were cross-trained and redeployed to our pediatric biocontainment unit to address the clinician strain in providing high-quality patient care during these unprecedented times. This manuscript discusses the effectiveness of using these clinicians while recognizing the challenges of managing a novel virus in a new unit.
Clinical Impact of Malunion After All-Arthroscopic Coracoclavicular Stabilization for Displaced and Unstable Lateral Clavicle Fractures
Authors: Degeorge Benjamin , Ravoyard Salomé , Lazerges Cyril , Toffoli Adriano , Chammas Michel , Coulet Bertrand
Published: December 2021

Objective:

To evaluate the clinical outcome of lateral clavicle malunion treated with all-arthroscopic coracoclavicular (CC) stabilization.

Design:

Retrospective, case series.

Setting:

Department of hand and upper extremity surgery, university hospital center.

Patients:

Forty-five patients with unstable and displaced lateral clavicle fracture treated between January 2015 and August 2019 were included in the study.

Intervention:

Closed reduction and arthroscopic CC stabilization using cortical buttons.

Main Outcome Measurements:

Shoulder pain and active motion. Patient-reported outcome measures included the Constant score, the Subjective Shoulder Value, the AcromioClavicular Joint Instability score, and the Specific AcromioClavicular Score. Radiographic evaluation assessed bony union and malunion.

Results:

Mean duration of follow-up was 25 months (12–60 months). Five patients (11%) had lateral clavicle nonunion and 7 (16%) had lateral clavicle malunion (5 in the coronal plane and 2 in the axial plane). Lateral clavicle malunion did not significantly affect clinical or functional outcomes (P > 0.05). Mean active shoulder motion was forward flexion 163 degrees (SD 28), abduction 162 degrees (SD 26), and external rotation 63 degrees (SD 21). On average, the patients scored 88.3 (SD 17.7) in the Constant score, 90% (SD 12) in the Subjective Shoulder Value, 88.8 (SD 9.4) in the AcromioClavicular Joint Instability score, and 11.4 (SD 8.5) for SACS. The overall complication rate was 38% (including 7 malunions, 5 nonunions, 2 adhesive capsulitis, and 3 button malpositions).

Conclusions:

Closed reduction and internal fixation of lateral clavicle fracture with all-arthroscopic CC stabilization using cortical button potentiates bony union but may generate lateral clavicle malunion, which does not affect the clinical or functional outcome. This result can be attributed to CC ligament healing and acromioclavicular joint congruence. All-arthroscopic CC stabilization is a minimally invasive but demanding surgical alternative for managing unstable and displaced lateral clavicle fracture.

Level of Evidence:

Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.
Recent advances in policy and practice translation of the evidence for additional omega-3 fatty acids and prematurity
Authors: Simmonds Lucy A. , Middleton Philippa F. , Makrides Maria
Published: December 2021

Purpose of review

This is a review of the most up-to-date research on the effectiveness of omega-3 fatty acids for reducing the risk of prematurity in well nourished women with access to high-quality obstetric care. It will provide an overview of the translation of the evidence on omega-3 screening into policy, and the latest research on how to implement the policy into practice.

Recent findings

Findings of the included clinical studies support that omega-3 supplementation for women with a singleton pregnancy who have a low omega-3 status reduces the risk of early preterm birth.

There is evidence that screening and providing appropriate advice to women with a singleton pregnancy who have a low omega-3 status can reduce their risk of early preterm birth, and avoiding supplementation for women who are replete will avoid unnecessary supplementation and potential harm.