bluuebunny/crossref_metadata_2025 huggingface dataset:
Further enhancement of the near-field on Au nanogap dimers using quasi-dark plasmon modes
Authors: Shibata Kizuku , Fujii Sho , Sun Quan , Miura Atsushi , Ueno Kosei
Published: March 2020

Metallic nanogap dimers are extremely useful for enhancing surface-enhanced Raman scattering and various nonlinear optical effects employing near-field enhancement effects induced by the localized surface plasmon resonance. However, the metallic nanogap dimers exhibit an intense light scattering due to the strong dipole–dipole interaction between two metallic nanostructures and, therefore, are not necessarily a structural design that exhibits the highest near-field enhancement due to the radiation loss. Here, we propose further enhancement of the near-field on metallic nanogap dimers using quasi-dark plasmon modes. By coupling with gold (Au) nanorods having the same plasmon resonant wavelength, but completely different sizes, a quasi-dark plasmon mode, which reduces the radiation loss slightly, is induced, resulting in the elongation of the plasmon dephasing time. As a result, the signal of surface-enhanced Raman scattering of crystal violet molecules adsorbed on the Au nanogap dimer is enhanced up to about three times as compared to that measured using the Au nanogap dimer without the Au nanorods. Scattering spectrum measurements as well as electromagnetic simulations were performed to clarify the mechanism for further enhancement of the near-field. The proposed coupled plasmonic system is expected to be advantageous, especially in enhancing nonlinear optical effects using plasmonic enhancement effects.
New interaction potentials for borate glasses with mixed network formers
Authors: Sundararaman Siddharth , Huang Liping , Ispas Simona , Kob Walter
Published: March 2020

We adapt and apply a recently developed optimization scheme used to obtain effective potentials for aluminosilicate glasses to include the network former boron into the interaction parameter set. As input data for the optimization, we used the radial distribution functions of the liquid at high temperature generated by ab initio molecular dynamics simulations, and density, coordination, and elastic modulus of glass at room temperature from experiments. The new interaction potentials are shown to reliably reproduce the structure, coordination, and mechanical properties over a wide range of compositions for binary alkali borates. Furthermore, the transferability of these new interaction parameters allows mixing to reliably reproduce the properties of various boroaluminate and borosilicate glasses.
Tunneling through a dielectric/ferromagnetic/ferroelectric three-step-like composite barrier
Authors: Wang Yihao , Zhou Peng , Liu Jiaolian , Ma Zhijun , Zhang Tianjin
Published: March 2020

Electron transport in ferroelectric tunnel junctions (FTJs) with a three-step-like barrier combining a dielectric, ferromagnetic, and ferroelectric was investigated theoretically. A significant enhanced tunneling electroresistance effect was observed as compared to traditional FTJs with a bilayer composite barrier. The spin polarization also could be enhanced in a certain orientation of ferroelectric polarization. A metal/dielectric/ferromagnetic/ferroelectric/metal FTJ with a large ferromagnetic thickness is preferred for the optimal performance. The ferroelectricity in the ferroelectric layer has a weak modulation effect on the spin polarization. This work provides a way to enhance the performance of FTJs and/or to control the spin-polarized electronic transport by structure engineering.
Synchronized excitation of magnetization dynamics via spin waves in Bi-YIG thin film by slot line waveguide
Authors: Koda Tetsunori , Muroga Sho , Endo Yasushi
Published: March 2020

We have studied magnetization dynamics of single Bi doped yttrium iron garnet single crystal (Bi-YIG) thin films by means of the high frequency power response induced by a slot line waveguide. Multiple absorption peaks that correspond to excitement states in magnetization dynamics appeared without the ferromagnetic resonance (FMR) condition. The peaks were strongly influenced by a waveguide linewidth and a distance between the lines. Micromagnetics simulation reveals that each line induces a local magnetization dynamics oscillation and generates spin waves. The spin wave that propagates from one of the lines interacts with the other side of local magnetization dynamics oscillation around the other line, resulting in an amplification of the oscillation when they are in synchronization with each other. This amplification occurs at both sides of the lines by interference. Thus, the possible mechanism of the excitation in the magnetization dynamics oscillation is the synchronization of mutual magnetization dynamics oscillation via spin waves. This technique resonantly excites the local magnetization dynamics without the FMR condition, which is applicable as a highly coherent spin wave source.
Beneficial influence of iodine substitution on the thermoelectric properties of Mo3Sb7
Authors: Tanusilp Sora-at , Wongprakarn Suphagrid , Kidkhunthod Pinit , Ohishi Yuji , Muta Hiroaki , Kurosaki Ken
Published: March 2020

Mo3Sb7 has been known as a p-type metal with commonly poor thermoelectric properties. However, Mo3Sb7 can be a high-efficiency thermoelectric material, owing to its capability of a metal–semiconductor transition, which can be realized by adding two valence electrons through elemental substitutions. Among the Mo3Sb7-based compounds, Mo3Sb5.4Te1.6 shows the highest figure of merit, zT, but additional valence electrons are needed for further improvement of the figure of merit. Here, we try to enhance the figure of merit of Mo3Sb7 by iodine-doping and by synthesizing and characterizing Mo3Sb7Ix with x = 0, 0.50, 0.75, 1.00, 1.25, and 1.50, where antimony (valence electrons = 5) is replaced by iodine (valence electrons = 7). We confirmed that the solubility limit for iodine in Mo3Sb7Ix was 1.25 < x < 1.50, and the figure of merit was enhanced by approximately 65% in maximum in x = 1.25.
Variation of local fields of pinned vortices with temperature
Authors: Zhang An-Lei , Gladilin Vladimir N. , Chen Xing-Hong , Van de Vondel Joris , Moshchalkov Victor V. , Ge Jun-Yi
Published: March 2020

Introducing artificial antidots into superconductors is an effective approach to manipulate vortex matter. It is of importance to study the effect of antidots on the magnetic field of a vortex and its temperature dependence. In our experiment, single vortices pinned at artificial antidots of different sizes as well as vortex pinned by random defects are investigated by using a scanning Hall probe microscope. At a certain height above the superconductor surface, the morphology of the vortices at various temperatures has been directly imaged. We have shown that the magnetic field distribution and its temperature dependences for all pinned vortices are similar. For both types of antidots, the penetration depth, rather than the antidot size, plays a dominant role in determining their vortex size at various temperatures. Ginzburg–Landau simulations well support our experiments. The results set the stage for further theoretical analysis of the local field variations of the pinned vortices with temperature as well as for the design and fine tuning of pinned vortex lattices that can be used as magnetic templates for other systems.
How magnetic fields affect dust dynamics in plasmas
Authors: Bandari Anashe
Published: March 2020

Dusty plasmas encounter magnetic fields in a variety of astrophysical and technological environments, but how the field impacts their behavior has not been thoroughly studied.
Intercalated graphite dispenser for ultracold-atomic experiments produces pure rubidium vapors
Authors: Frank Jodi Ackerman
Published: March 2020

The dispenser, based on highly ordered pyrolytic graphite, holds significantly more of the alkali metal than conventional chromate salt dispensers.
The responsive behaviors of bilayer membrane under uniaxial mechanical probe
Authors: Liu Baopi , Zhang Xinghua , Yan Dadong
Published: March 2020

In experiments, atomic force microscopy technology was used to measure the modulus of the membrane. However, these studies mainly focus on the linear responsive behavior. In the present work, a theoretical study is performed to show the nonlinear responsive behavior, which includes the stretching induced structural transitions. It demonstrates that the structural transition of the bilayer membrane takes place during the stretching process of the mechanical probe. A vertical cylindrical micelle can be obtained by stretching the membrane under deep compression conditions, and the cylindrical micelle can grow continuously along the axial direction. Moreover, under shallow compression conditions, the probe pulls a spherical micelle from the membrane, and then, the membrane returns to flatness. A comprehensive study is performed to show the mechanism of the responsive behaviors of the structural transition during the compression and stretching processes. When the probe acts on the B-rich layer, it is more likely to pull out a regular micelle. However, when the probe acts on the bottom A-rich layer, complex vesicles are more likely to be pulled out from the bilayer membrane. This study provides a comprehensive diagram of the mechanical responsive behavior of the membrane, which would be a guide for an experiment of biomembranes and the design of new self-assembled structures.
Small extracellular vesicles from human adipose‐derived stem cells attenuate cartilage degeneration
Authors: Woo Chang Hee , Kim Hark Kyun , Jung Gun Young , Jung Youn Jae , Lee Kyoung Soo , Yun Ye Eun , Han Jihoon , Lee Jeongmi , Kim Woo Sung , Choi Ji Suk , Yang Siyoung , Park Jae Hyung , Jo Dong‐Gyu , Cho Yong Woo
Published: March 2020

Osteoarthritis (OA) is a chronic degenerative disease of articular cartilage that is the most common joint disease worldwide. Mesenchymal stem cells (MSCs) have been the most extensively explored for the treatment of OA. Recently, it has been demonstrated that MSC‐derived extracellular vesicles (EVs) may contribute to the potential mechanisms of MSC‐based therapies. In this study, we investigated the therapeutic potential of human adipose‐derived stem cells EVs (hASC‐EVs) in alleviating OA, along with the mechanism. EVs were isolated from the culture supernatants of hASCs by a multi‐filtration system based on the tangential flow filtration (TFF) system. The isolated EVs were characterised using dynamic light scattering (DLS), transmission electron microscopy (TEM), nanoparticle tracking analysis (NTA) and flow cytometry analysis. The hASC‐EVs not only promoted the proliferation and migration of human OA chondrocytes, but also maintained the chondrocyte matrix by increasing type Ⅱ collagen synthesis and decreasing MMP‐1, MMP‐3, MMP‐13 and ADAMTS‐5 expression in the presence of IL‐1β in vitro. Intra‐articular injection of hASC‐EVs significantly attenuated OA progression and protected cartilage from degeneration in both the monosodium iodoacetate (MIA) rat and the surgical destabilisation of the medial meniscus (DMM) mouse models. In addition, administration of hASC‐EVs inhibited the infiltration of M1 macrophages into the synovium. Overall results suggest that the hASC‐EVs should be considered as a potential therapeutic approach in the treatment of OA.
4.6 T generated by a high-temperature superconducting ring magnet
Authors: Ali Muhammad Zulfiqar , Zheng Jinxing , Huber Felix , Zhang Zhiwei , Yuan Weijia , Zhang Min
Published: March 2020

We report here a record 4.6 T trapped field generated by high temperature superconducting (HTS) persistent current loops using a HTS ring structure. By stacking 200 HTS rings into a compact magnet 90 mm in diameter, we performed a field cooling magnetisation at 25 K. The main advantage of the new magnet compared to existing trapped field HTS magnets is that the magnetic field is in the parallel direction to the ab plane of the HTS, leading to higher critical currents in the same magnetic field. Therefore, compact HTS magnets can be developed based on this principle to achieve high magnetic fields. Experimental results show that the final trapped field distribution depends on the ring geometry. We developed a new three dimensional model to simulate the magnetic field distribution within the HTS ring magnet and good agreement between experiments and simulation have been found. The temperature dependency and ramping rate dependency have been studied numerically as potential factors to influence the magnet field. The proposed HTS ring magnet will have promising applications in medical imaging devices, e.g. MRI, as well as electrical machines.
Invasion, isolation and evolution shape population genetic structure in Campanula rotundifolia
Authors: Wilson Julia , Perry Annika , Shepherd Jessica R , Durán-Castillo Mario , Jeffree Christopher E , Cavers Stephen
Published: March 2020

The distribution and genetic structure of most plant species in Britain and Ireland bear the imprint of the last ice age. These patterns were largely shaped by random processes during recolonization but, in angiosperms, whole-genome duplication may also have been important. We investigate the distribution of cytotypes of Campanula rotundifolia, considering DNA variation, postglacial colonization, environmental partitioning and reproductive barriers. Cytotypes and genome size variation from across the species’ range were determined by flow cytometry and genetic variation was assessed using cpDNA markers. A common garden study examined growth and flowering phenology of tetraploid, pentaploid and hexaploid cytotypes and simulated a contact zone for investigation of reproductive barriers. Irish populations were entirely hexaploid. In Britain, hexaploids occurred mostly in western coastal populations which were allopatric with tetraploids, and in occasional sympatric inland populations. Chloroplast markers resolved distinct genetic groups, related to cytotype and geographically segregated; allopatric hexaploids were distinct from tetraploids, whereas sympatric hexaploids were not. Genome downsizing occurred between cytotypes. Progeny of open-pollinated clones from the contact zone showed that maternal tetraploids rarely produced progeny of other cytotypes, whereas the progeny of maternal hexaploids varied, with frequent pentaploids and aneuploids. The presence of distinctive hexaploid chloroplast types in Ireland, Scottish islands and western mainland Britain indicates that its establishment preceded separation of these land masses by sea-level rise c. 16 000 years BP. This group did not originate from British tetraploids and probably diverged before postglacial invasion from mainland Europe. The combination of cytotype, molecular, contact zone and common garden data shows an overall pattern reflecting postglacial colonization events, now maintained by geographic separation, together with more recent occasional local in situ polyploidisation. Reproductive barriers favour the persistence of the tetraploid to the detriment of the hexaploid.
Positioning Selves in Narrative Accounts of Military Trauma
Authors: Laskey Brenda , Stirling Lesley
Published: March 2020

Linguistic and narrative strategies employed in two dyadic interviews of male veterans of the war in Afghanistan were analysed and compared. Each interviewee told chains of connected stories that positioned them in relation to catastrophic events and their effects. These incidents were framed as being linked to decisions that the teller had taken in perilous circumstances. Sequences of generic clauses in sections of orientation were used to manage knowledge asymmetries, to establish story world norms, to display professional, soldierly and veteran identities and to present danger, serious injury, and death as normative in the context of military work in a conflict zone. Resolutions to narratives involving death or injury resided not in specific narrative event clauses but in sections of evaluation that framed the outcome of a preceding story chain in terms of its personal, current significance to the speaker. Our exploration of contrasting accounts of similarly catastrophic events by two storytellers, one of whom was diagnosed with posttraumatic stress disorder, offers insights into ways in which trauma is represented that could be useful in psychotherapeutic contexts.
Setting the basis of best practices and standards for curation and annotation of logical models in biology—highlights of the [BC]2 2019 CoLoMoTo/SysMod Workshop
Authors: Niarakis Anna , Kuiper Martin , Ostaszewski Marek , Malik Sheriff Rahuman S , Casals-Casas Cristina , Thieffry Denis , Freeman Tom C , Thomas Paul , Touré Vasundra , Noël Vincent , Stoll Gautier , Saez-Rodriguez Julio , Naldi Aurélien , Oshurko Eugenia , Xenarios Ioannis , Soliman Sylvain , Chaouiya Claudine , Helikar Tomáš , Calzone Laurence
Published: March 2020

The fast accumulation of biological data calls for their integration, analysis and exploitation through more systematic approaches. The generation of novel, relevant hypotheses from this enormous quantity of data remains challenging. Logical models have long been used to answer a variety of questions regarding the dynamical behaviours of regulatory networks. As the number of published logical models increases, there is a pressing need for systematic model annotation, referencing and curation in community-supported and standardised formats. This article summarises the key topics and future directions of a meeting entitled ‘Annotation and curation of computational models in biology’, organised as part of the 2019 [BC]2 conference. The purpose of the meeting was to develop and drive forward a plan towards the standardised annotation of logical models, review and connect various ongoing projects of experts from different communities involved in the modelling and annotation of molecular biological entities, interactions, pathways and models. This article defines a roadmap towards the annotation and curation of logical models, including milestones for best practices and minimum standard requirements.
The role of the immune system in tendon healing: a systematic review
Authors: Chisari Emanuele , Rehak Laura , Khan Wasim S , Maffulli Nicola
Published: March 2020

Introduction

The role of the immune system in tendon healing relies on polymorphonucleocytes, mast cells, macrophages and lymphocytes, the ‘immune cells’ and their cytokine production. This systematic review reports how the immune system affects tendon healing.

Sources of data

We registered our protocol (registration number: CRD42019141838). After searching PubMed, Embase and Cochrane Library databases, we included studies of any level of evidence published in peer-reviewed journals reporting clinical or preclinical results. The PRISMA guidelines were applied, and risk of bias and the methodological quality of the included studies were assessed. We excluded all the articles with high risk of bias and/or low quality after the assessment. We included 62 articles assessed as medium or high quality.

Areas of agreement

Macrophages are major actors in the promotion of proper wound healing as well as the resolution of inflammation in response to pathogenic challenge or tissue damage. The immune cells secrete cytokines involving both pro-inflammatory and anti-inflammatory factors which could affect both healing and macrophage polarization.

Areas of controversy

The role of lymphocytes, mast cells and polymorphonucleocytes is still inconclusive.

Growing points

The immune system is a major actor in the complex mechanism behind the healing response occurring in tendons after an injury. A dysregulation of the immune response can ultimately lead to a failed healing response.

Areas timely for developing research

Further studies are needed to shed light on therapeutic targets to improve tendon healing and in managing new way to balance immune response.
A Novel Approach for a Novel Pathogen: Using a Home Assessment Team to Evaluate Patients for COVID-19
Authors: Bryson-Cahn Chloe , Duchin Jeffrey , Makarewicz Vanessa A , Kay Meagan , Rietberg Krista , Napolitano Nathanael , Kamangu Carole , Dellit Timothy H , Lynch John B
Published: March 2020

Thousands of people in the United States have required testing for SARS-CoV-2. Evaluation for a special pathogen is resource intensive. We report an innovative approach to home assessment that, in collaboration with public health, enables safe evaluation and specimen collection outside the healthcare setting, avoiding unnecessary exposures and resource utilization.
The Integrase Inhibitors Dolutegravir and Raltegravir Exert Proadipogenic and Profibrotic Effects and Induce Insulin Resistance in Human/Simian Adipose Tissue and Human Adipocytes
Authors: Gorwood Jennifer , Bourgeois Christine , Pourcher Valérie , Pourcher Guillaume , Charlotte Frédéric , Mantecon Matthieu , Rose Cindy , Morichon Romain , Atlan Michael , Le Grand Roger , Desjardins Delphine , Katlama Christine , Fève Bruno , Lambotte Olivier , Capeau Jacqueline , Béréziat Véronique , Lagathu Claire
Published: March 2020

Background

Although some integrase strand transfer inhibitors (INSTIs) promote peripheral and central adipose tissue/weight gain in people with human immunodeficiency virus (PHIV), the underlying mechanism has not been identified. Here, we used human and simian models to assess the impact of INSTIs on adipose tissue phenotype and function.

Methods

Adipocyte size and fibrosis were determined in biopsies of subcutaneous and visceral adipose tissue (SCAT and VAT, respectively) from 14 noninfected macaques and 19 PHIV treated or not treated with an INSTI. Fibrosis, adipogenesis, oxidative stress, mitochondrial function, and insulin sensitivity were assessed in human proliferating or adipocyte-differentiated adipose stem cells after long-term exposure to dolutegravir or raltegravir.

Results

We observed elevated fibrosis, adipocyte size, and adipogenic marker expression in SCAT and VAT from INSTI-treated noninfected macaques. Adiponectin expression was low in SCAT. Accordingly, SCAT and VAT samples from INSTI-exposed patients displayed higher levels of fibrosis than those from nonexposed patients. In vitro, dolutegravir and, to a lesser extent, raltegravir were associated with greater extracellular matrix production and lipid accumulation in adipose stem cells and/or adipocytes as observed in vivo. Despite the INSTIs’ proadipogenic and prolipogenic effects, these drugs promoted oxidative stress, mitochondrial dysfunction, and insulin resistance.

Conclusions

Dolutegravir and raltegravir can directly impact adipocytes and adipose tissue. These INSTIs induced adipogenesis, lipogenesis, oxidative stress, fibrosis, and insulin resistance. The present study is the first to shed light on the fat modifications observed in INSTI-treated PHIV.
Low-level expression of the Type II restriction–modification system confers potent bacteriophage resistance in Escherichia coli
Authors: Wilkowska Karolina , Mruk Iwona , Furmanek-Blaszk Beata , Sektas Marian
Published: March 2020

Restriction–modification systems (R–M) are one of the antiviral defense tools used by bacteria, and those of the Type II family are composed of a restriction endonuclease (REase) and a DNA methyltransferase (MTase). Most entering DNA molecules are usually cleaved by the REase before they can be methylated by MTase, although the observed level of fragmented DNA may vary significantly. Using a model EcoRI R–M system, we report that the balance between DNA methylation and cleavage may be severely affected by transcriptional signals coming from outside the R–M operon. By modulating the activity of the promoter, we obtained a broad range of restriction phenotypes for the EcoRI R–M system that differed by up to 4 orders of magnitude in our biological assays. Surprisingly, we found that high expression levels of the R–M proteins were associated with reduced restriction of invading bacteriophage DNA. Our results suggested that the regulatory balance of cleavage and methylation was highly sensitive to fluctuations in transcriptional signals both up- and downstream of the R–M operon. Our data provided further insights into Type II R–M system maintenance and the potential conflict within the host bacterium.
Samaritan Bundles: Fundraising Competition and Inefficient Clustering in NGO Projects
Authors: Aldashev Gani , Marini Marco , Verdier Thierry
Published: March 2020

This article provides a theoretical framework to understand the tendency of non-governmental organisations (NGOs) to cluster and the circumstances under which such clustering is socially undesirable. NGOs compete through fundraising for donations and choose issues to focus their projects on. Donors have latent willingness-to-give that may differ across issues, but they need to be ‘awakened' to give. Raising funds focusing on the same issue creates positive informational spillovers across NGOs. Each NGO chooses whether to compete in the same market (clustering) with spillovers, or to face weaker competition under issue specialisation. We show that equilibrium clustering is more likely to occur when the share of multiple-issue donors is relatively large, and when the fundraising technology is sufficiently efficient. Moreover, this situation is socially inefficient when the cost of fundraising takes intermediate values and the motivation for donors’ giving is relatively high. We illustrate the mechanisms of the model with several case studies.
The End of Dominance? Evaluating Measures of Socio-Economic Background in Stratification Research
Authors: Thaning Max , Hällsten Martin
Published: March 2020

We analyse how to best combine information on both parents’ socio-economic status (SES) in intergenerational research. This can be done by utilizing separate measures for each parent, taking averages over parents, modelling interactions, or only using the highest value across parents—the latter commonly referred to as the dominance approach. Our brief literature review suggests that (i) the dominance tradition is widespread, although seldom theoretically or empirically justified and (ii) parental interactive models are not widely used. We assess how much of the sibling correlations in continuous measures of education, occupation, and earnings that are explained by parents’ SES in the same dimensions using the different operationalizations. The dominance approach performs poorer than other models of parental SES. For the total contribution of socio-economic background, we find a bias of about 4–6 per cent for children’s education and occupational outcomes compared with other approaches. We also conduct a separate evaluation of nominal EGP social class operationalizations and find that the dominance approach is the most suboptimal choice compared with the alternatives. In conclusion, parental averages are preferred over dominance, as an attractive and parsimonious one variable alternative, although the highest explanatory power is attributed to models using two parental measures and an interaction term.
Results, barriers and enablers in atrial fibrillation case finding: barriers in opportunistic atrial fibrillation case finding—a cross-sectional study
Authors: Ballesta-Ors Juan , Clua-Espuny Josep L , Gentille-Lorente Delicia I , Lechuga-Duran Iñigo , Fernández-Saez José , Muria-Subirats Eulalia , Blasco-Mulet María , Lorman-Carbo Blanca , Alegret Josep M
Published: March 2020

Background

Atrial fibrillation (AF) is often asymptomatic, and screening is not routinely undertaken.

Objective

Evaluate the feasibility and effectiveness of a population-based case finding program and to identify the enablers of and/or barriers to its implementation.

Methods

We conducted a cross-sectional study of a health care case finding program for AF from 1 January 2016, to 31 December 2017, that included 48 336 people ≥60 years of age in the region of Terresde l’Ebre (Catalonia, Spain). We analysed the effect on the prevalence of AF and, stratified by age, on the incidence of new diagnoses of AF. We assessed the sociodemographic and clinical variables related to the realization of a case finding.

Results

A total of 32 090 (62.4%) people were screened for AF. We observed a significant increase in the AF prevalence after 2 years of program intervention (5.9–7.7%; P < 0.001). The detection of new AF cases was significantly higher in the case finding group across the whole of the age range, and 765 (2.6%) new AF cases were diagnosed using case finding. The factors that were significantly associated with an underuse of case finding were: age <70 years, urban residence, institutionalized status, Pfeiffer score ≥2, Charlson score >3 and number of visits <7/year.

Conclusions

A health care program of case finding is feasible and is associated with a significant increase in the prevalence and incidence of AF. The results depend on factors such as the ease of access to health care, age, place of residence and comorbidities.
What Is in Umbilicaria pustulata? A Metagenomic Approach to Reconstruct the Holo-Genome of a Lichen
Authors: Greshake Tzovaras Bastian , Segers Francisca H I D , Bicker Anne , Dal Grande Francesco , Otte Jürgen , Anvar Seyed Yahya , Hankeln Thomas , Schmitt Imke , Ebersberger Ingo
Published: March 2020

Lichens are valuable models in symbiosis research and promising sources of biosynthetic genes for biotechnological applications. Most lichenized fungi grow slowly, resist aposymbiotic cultivation, and are poor candidates for experimentation. Obtaining contiguous, high-quality genomes for such symbiotic communities is technically challenging. Here, we present the first assembly of a lichen holo-genome from metagenomic whole-genome shotgun data comprising both PacBio long reads and Illumina short reads. The nuclear genomes of the two primary components of the lichen symbiosis—the fungus Umbilicaria pustulata (33 Mb) and the green alga Trebouxia sp. (53 Mb)—were assembled at contiguities comparable to single-species assemblies. The analysis of the read coverage pattern revealed a relative abundance of fungal to algal nuclei of ∼20:1. Gap-free, circular sequences for all organellar genomes were obtained. The bacterial community is dominated by Acidobacteriaceae and encompasses strains closely related to bacteria isolated from other lichens. Gene set analyses showed no evidence of horizontal gene transfer from algae or bacteria into the fungal genome. Our data suggest a lineage-specific loss of a putative gibberellin-20-oxidase in the fungus, a gene fusion in the fungal mitochondrion, and a relocation of an algal chloroplast gene to the algal nucleus. Major technical obstacles during reconstruction of the holo-genome were coverage differences among individual genomes surpassing three orders of magnitude. Moreover, we show that GC-rich inverted repeats paired with nonrandom sequencing error in PacBio data can result in missing gene predictions. This likely poses a general problem for genome assemblies based on long reads.
A Potential Influenza Pandemic Modelled in Greek Refugee Camps
Authors: Searle C , Sutherland G P
Published: March 2020

Research indicate a significant relationship between the spread of respiratory symptoms and poor housing conditions that arise due to overcrowding — both of which are typically prevalent in refugee camps. The World Health Organization states that the impact of a novel pandemic influenza virus on refugee and displaced populations is expected to be severe. There is, however, insufficient data on the health status of refugees and the spread of common diseases within these camps. In this study, agent-based simulation is employed to address the lack of data and to gain an understanding of the spread and prevalence of a communicable disease within refugee camps. The model aims to explore the spread of a potential influenza pandemic within a Greek refugee camp by modelling personal characteristics of refugees and their interactions with other members. The ability to model, with a reasonable level of accuracy, the spread of a potential influenza pandemic could assist humanitarian aid in combating the problem with evidence-based policy decisions.
Mild drought in the vegetative stage induces phenotypic, gene expression, and DNA methylation plasticity in Arabidopsis but no transgenerational effects
Authors: Van Dooren Tom J M , Silveira Amanda Bortolini , Gilbault Elodie , Jiménez-Gómez José M , Martin Antoine , Bach Liên , Tisné Sébastien , Quadrana Leandro , Loudet Olivier , Colot Vincent
Published: March 2020

There is renewed interest in whether environmentally induced changes in phenotypes can be heritable. In plants, heritable trait variation can occur without DNA sequence mutations through epigenetic mechanisms involving DNA methylation. However, it remains unknown whether this alternative system of inheritance responds to environmental changes and if it can provide a rapid way for plants to generate adaptive heritable phenotypic variation. To assess potential transgenerational effects induced by the environment, we subjected four natural accessions of Arabidopsis thaliana together with the reference accession Col-0 to mild drought in a multi-generational experiment. As expected, plastic responses to drought were observed in each accession, as well as a number of intergenerational effects of the parental environments. However, after an intervening generation without stress, except for a very few trait-based parental effects, descendants of stressed and non-stressed plants were phenotypically indistinguishable irrespective of whether they were grown in control conditions or under water deficit. In addition, genome-wide analysis of DNA methylation and gene expression in Col-0 demonstrated that, while mild drought induced changes in the DNA methylome of exposed plants, these variants were not inherited. We conclude that mild drought stress does not induce transgenerational epigenetic effects.
Supersolar metallicity in G0–G3 main-sequence stars with V < 15. II. An extension of the sample
Authors: Chávez M , Tapia-Schiavon C , Bertone E , López-Valdivia R
Published: March 2020

We present the spectroscopic analysis at intermediate resolution of a new sample of 146 Sun-like stars (of spectral types G0–G3 and luminosity class V), which complements the data set of 233 targets previously investigated. Aimed at identifying objects with supersolar metallicity, we conducted observations at the Observatorio Astrofísico Guillermo Haro and derived the basic stellar atmospheric parameters, namely the effective temperature, surface gravity, and global metallicity, based on a set of absorption spectroscopic indices in the wavelength region 3800–4800 Å. The newly derived set of parameters is in good agreement with previous determinations collected from sources in the literature. Considering the full sample of our investigation (379 stars), we also compared the effective temperatures of stars in common (354 objects) with Gaia DR2 for which temperatures are available, and found that, on average, our values are about 100 K higher. We show that most of the largest temperature discrepancies can plausibly be ascribed to interstellar extinction effects on Gaia’s photometry. Finally, within the working sample we found four more stars that present supermetallicity, one of which was previously reported in the literature.
ZTF J1901+5309: a 40.6-min orbital period eclipsing double white dwarf system
Authors: Coughlin Michael W , Burdge Kevin , Sterl Phinney E , van Roestel Jan , Bellm Eric C , Dekany Richard G , Delacroix Alexandre , Duev Dmitry A , Feeney Michael , Graham Matthew J , Kulkarni S R , Kupfer Thomas , Laher Russ R , Masci Frank J , Prince Thomas A , Riddle Reed , Rosnet Philippe , Smith Roger , Serabyn Eugene , Walters Richard
Published: March 2020

The Zwicky Transient Facility has begun to discover binary systems with orbital periods that are less than 1 h. Combined with dedicated follow-up systems, which allow for high-cadence photometry of these sources, systematic confirmation and characterization of these sources are now possible. Here, we report the discovery of ZTF J190125.42+530929.5, a 40.6-min orbital period, eclipsing double white dwarf binary. Both photometric modelling and spectroscopic modelling confirm its nature, yielding an estimated inclination of $i = 86.2^{+0.6}_{-0.2}\, \rm deg$ and primary and secondary effective temperatures of $\textrm{{T}}_\textrm{eff} = 28\,000^{+500}_{-500}$ and $17\,600^{+400}_{-400}\, \mathrm{ K}$, respectively. This system adds to a growing list of sources for future gravitational-wave detectors and contributes to the demographic analysis of double degenerates.
Prediction of Unruptured Intracranial Aneurysm Evolution: The UCAN Project
Authors: L’Allinec Vincent , Chatel Stéphanie , Karakachoff Matilde , Bourcereau Emmanuelle , Lamoureux Zeineb , Gaignard Alban , Autrusseau Florent , Jouan Solène , Vion Anne-Clemence , Loirand Gervaise , Desal Hubert , Naggara Olivier , Redon Richard , Edjlali Myriam , Bourcier Romain ,   on behalf of the UCAN (Unruptured Cerebral Aneurysm) Investigators
Published: March 2020

BACKGROUND

Management of small (<7 mm) unruptured intracranial aneurysms (UIA) remains controversial. Retrospective studies have suggested that post gadolinium arterial wall enhancement (AWE) of UIA on magnetic resonance imaging (MRI) may reflect aneurysm wall instability, and hence may highlight a higher risk of UIA growth. This trial aims at exploring wall imaging findings of UIAs with consecutive follow-up to substantiate these assumptions.

OBJECTIVE

To develop diagnostic and predictive tools for the risk of IA evolution. Our aim is to demonstrate in clinical practice the predictive value of AWE for UIA growth. The growth will be determined by any modification of the UIA measurement. UIA growth and the UIA wall enhancement will be assessed in consensus by 2 expert neuroradiologists.

METHODS

The French prospective UCAN project is a noninterventional international wide and multicentric cohort. UIA of bifurcation between 3 and 7 mm for whom a clinical and imaging follow-up without occlusion treatment was scheduled by local multidisciplinary staff will be included. Extensive clinical, biological, and imaging data will be recorded during a 3-yr follow-up.

EXPECTED OUTCOMES

Discovering to improve the efficiency of UIA follow-up by identifying additional clinical, imaging, biological, and anatomic risk factors of UIA growth.

DISCUSSION

A prospective nationwide recruitment allows for the inclusion of a large cohort of patients with UIA. It will combine clinical phenotyping and specific imaging with AWE screening. It will enable to exploit metadata and to explore some pathophysiological pathways by crossing clinical, genetic, biological, and imaging information.
Capacity to consent to research participation in adults with metastatic cancer: comparisons of brain metastasis, non-CNS metastasis, and healthy controls
Authors: Mulhauser Kyler , Marotta Dario A , Gerstenecker Adam , Wilhelm Gabrielle , Myers Terina , Gammon Meredith , Vance David E , Nabors Burt , Fiveash John , Triebel Kristen
Published: March 2020

Background

To evaluate the ability of individuals with metastatic cancer to provide informed consent to research participation, we used a structured vignette-based interview to measure 4 consenting standards across 3 participant groups.

Methods

Participants included 61 individuals diagnosed with brain metastasis, 41 individuals diagnosed with non-CNS metastasis, and 17 cognitively intact healthy controls. All groups were evaluated using the Capacity to Consent to Research Instrument (CCRI), a performance-based measure of research consent capacity. The ability to provide informed consent to participate in research was evaluated across 4 consent standards: expressing choice, appreciation, reasoning, and understanding. Capacity performance ratings (intact, mild/moderate impairment, severe impairment) were identified based on control group performance.

Results

Results revealed that the brain metastasis group performed significantly lower than healthy controls on the consent standard of understanding, while both metastatic cancer groups performed below controls on the consent standard of reasoning. Both metastatic cancer groups performed similar to controls on the standards of appreciation and expressing choice. Approximately 60% of the brain metastasis group, 54% of the non-CNS metastasis group, and 18% of healthy controls showed impaired research consent capacity.

Conclusions

Our findings, using a performance-based assessment, are consistent with other research indicating that the research consent process may be overly cumbersome and confusing. This, in turn, may lead to research consent impairment not only in patient groups but also in some healthy adults with intact cognitive ability.
Symmetry selective directionality in near-field acoustics
Authors: Long Yang , Ge Hao , Zhang Danmei , Xu Xiangyuan , Ren Jie , Lu Ming-Hui , Bao Ming , Chen Hong , Chen Yan-Feng
Published: March 2020

Understanding unidirectional and topological wave phenomena requires the unveiling of intrinsic geometry and symmetry for wave dynamics. This is essential yet challenging for the flexible control of near-field evanescent waves, highly desirable in broad practical scenarios ranging from information communication to energy radiation. However, exploitations of near-field waves are limited by a lack of fundamental understanding about inherent near-field symmetry and directional coupling at sub-wavelengths, especially for longitudinal waves. Here, based on the acoustic wave platform, we show the efficient selective couplings enabled by near-field symmetry properties. Based on the inherent symmetry properties of three geometrically orthogonal vectors in near-field acoustics, we successfully realize acoustic Janus, Huygens, spin sources and quadrupole hybrid sources, respectively. Moreover, we experimentally demonstrate fertile symmetry selective directionality of those evanescent modes, supported by two opposite meta-surfaces. The symmetry properties of the near-field acoustic spin angular momenta are revealed by directly measuring local vectorial fields. Our findings advance the understanding of symmetries in near-field physics, supply feasible approaches for directional couplings, and pave the way for promising acoustic devices in the future.
Gender-Based Violence, Law, Justice and Health: Some Reflections
Authors: Gangoli Geetanjali
Published: March 2020

This article is a response to the Lancet Commission on the Legal Determinants of Health from gendered perspectives and focusing on gender-based violence and abuse. The Lancet Commission sees the role of law as positive, indeed central in providing justice in global contexts, and this contribution explores and unpacks this assertion, drawing on some examples from India and elsewhere. Some feminists have argued that law and justice are incompatible for women, and this is sometimes borne out when we look at legal reforms and interventions in the field of gender-based violence. However, we also explore the ways in which some women have used legal reforms in creative ways to destabilize patriarchal norms, and more broadly, how absence of legal protection can undermine access to rights. We conclude that law can have a symbolic relationship with justice.
Reliability of Vestibular Perceptual Threshold Testing About the Yaw Axis
Authors: Lee Tiffany L. , Shayman Corey S. , Oh Yonghee , Peterka Robert J. , Hullar Timothy E.
Published: March 2020

Objectives:

Vestibular reflexes have traditionally formed the cornerstone of vestibular evaluation, but perceptual tests have recently gained attention for use in research studies and potential clinical applications. However, the unknown reliability of perceptual thresholds limits their current importance. This is addressed here by establishing the test-retest reliability of vestibular perceptual testing.

Design:

Perceptual detection thresholds to earth-vertical, yaw-axis rotations were collected in 15 young healthy people. Participants were tested at two time intervals (baseline, 5 to 14 days later) using an adaptive psychophysical procedure.

Results:

Thresholds to 1 Hz rotations ranged from 0.69 to 2.99°/s (mean: 1.49°/s; SD: 0.63). They demonstrated an excellent intraclass correlation (0.92; 95% confidence interval: 0.77 to 0.97) with a minimum detectable difference of 0.45°/s.

Conclusions:

The excellent test-retest reliability of perceptual vestibular testing supports its use as a research tool and motivates further exploration for its use as a novel clinical technique.
Proximal Junctional Kyphosis in Degenerative Sagittal Deformity After Under- and Overcorrection of Lumbar Lordosis
Authors: Im Sang-Kyu , Lee Jung-Hee , Kang Kyung-Chung , Shin Sung Joon , Lee Ki Young , Park Jong Jun , Kim Man Ho
Published: March 2020

Study Design.

Retrospective study.

Objective.

To analyze proximal junctional kyphosis (PJK) occurrence and surgical outcomes according to degree of lumbar lordosis (LL) correction relative to pelvic incidence (PI). In addition, risk factors of PJK including LL and sagittal vertical axis (SVA) correction were investigated.

Summary of Background Data.

PJK is a common complication after adult spinal deformity surgery, and many factors are known to be associated with PJK. However, the effect of degree of LL correction on PJK occurrence is not fully understood.

Methods.

Eighty-three degenerative sagittal imbalance patients treated with deformity correction and long instrumented fusion to the sacrum with a minimum follow-up of 2 years were studied. Patients were divided into three groups according to their postoperative LL angle relative to PI using the SRS-Schwab classification: Group A (undercorrection, PI-LL> 10°), Group B (ideal correction, −10°<PI-LL≤10°), and Group C (overcorrection, PI-LL≤−10°). Prevalence, classification, and period of PJK occurrence were compared, and radiographic and clinical outcomes were analyzed. In addition, risk factors for PJK were evaluated.

Results.

Overall PJK prevalence was 36.1% (30/83), and ratio of optimal SVA at postoperative and last follow-up were significantly higher in Group C (P < 0.001, P < 0.001). Nevertheless, there was no significant difference in PJK prevalence among three groups (40% vs. 37.5% vs. 34.1%; P = 0.907). Group C had better clinical outcomes (last follow-up ODI, VAS of LBP) than Group A (10.0 vs. 18.4; P < 0.001 and 1.5 vs. 4.0; P < 0.001). The increases in LL or SVA correction degree were not associated with PJK occurrence (P = 0.304, P = 0.201).

Conclusion.

Overcorrection showed good surgical outcomes without increasing PJK prevalence. Degrees of LL and SVA correction do not act as risk factors for PJK. Therefore, in adult spinal deformity patients, LL correction greater than PI may be a good choice that can result in better clinical outcomes without increasing risk of PJK.

Level of Evidence: 4