bluuebunny/crossref_metadata_2025 huggingface dataset:
Vertical carrier transport in strain-balanced InAs/InAsSb type-II superlattice material
Authors: Casias Lilian K. , Morath Christian P. , Steenbergen Elizabeth H. , Umana-Membreno Gilberto A. , Webster Preston T. , Logan Julie V. , Kim Jin K. , Balakrishnan Ganesh , Faraone Lorenzo , Krishna Sanjay
Published: May 2020

Anisotropic carrier transport properties of unintentionally doped InAs/InAs0.65Sb0.35 type-II strain-balanced superlattice material are evaluated using temperature- and field-dependent magnetotransport measurements performed in the vertical direction on a substrate-removed metal-semiconductor-metal device structure. To best isolate the measured transport to the superlattice, device fabrication entails flip-chip bonding and backside device processing to remove the substrate material and deposit contact metal directly to the bottom of an etched mesa. High-resolution mobility spectrum analysis is used to calculate the conductance contribution and corrected mixed vertical-lateral mobility of the two carrier species present. Combining the latter with lateral mobility results from in-plane magnetotransport measurements on identical superlattice material allows for the calculation of the true vertical majority electron and minority hole mobilities; amplitudes of 4.7 ×103 cm2/V s and 1.60 cm2/V s are determined at 77 K, respectively. The temperature-dependent results show that vertical hole mobility rapidly decreases with decreasing temperature due to trap-induced localization and then hopping transport, whereas vertical electron mobility appears phonon scattering-limited at high temperature, giving way to interface roughness scattering at low temperatures, analogous to the lateral electron mobility but with a lower overall magnitude.
Relation between dielectric permittivity and electrocaloric effect under high electric fields in the Pb(Mg1/3Nb2/3)O3-based ceramics
Authors: Fulanović Lovro , Bradeško Andraž , Novak Nikola , Malič Barbara , Bobnar Vid
Published: May 2020

The correlation between dielectric permittivity and electrocaloric (EC) temperature change (ΔTEC) has been investigated in (1 − x)Pb(Mg1/3Nb2/3)O3−xPbTiO3 (PMN–100xPT, with x = 0, 0.05, and 0.10) relaxor ferroelectric ceramics. At a given electric field, both peak temperatures, including the temperature of the permittivity peak (Tm) and the temperature of the maximum of the ΔTEC (TEC max) increase with increasing PT content. The peak of the dielectric permittivity is, regardless of the applied electric field, always at a higher temperature than is the TEC max, and the temperature gap between both maxima progressively increases with increasing applied DC bias. This is particularly true above the threshold field, which induces the long-range ordered ferroelectric state. The results, which are explained in terms of the electric field–temperature phase diagram of relaxor systems, thus reveal that Tm can only roughly mark the temperature of the upper boundary of the temperature–electric field window, where the EC responsivity (ΔTEC/ΔE) is the highest.
Experimental use of the inflection point test for force deconvolution in frequency-modulation atomic force microscopy to turn an ill-posed situation into a well-posed one by proper choice of amplitude
Authors: Huber Ferdinand , Giessibl Franz J.
Published: May 2020

Frequency-modulation atomic force microscopy allows one to measure the force between a sharp tip and a sample and, ultimately, the force between two single atoms with outstanding precision. To extract forces from the measured frequency shifts, a deconvolution algorithm is required. Mathematically, the deconvolution problem is an inversion problem. It has been shown that deconvolution can be ill-posed, resulting in erroneous forces values. Whether the deconvolution is well-posed or ill-posed is determined by two factors: the shape of the force–distance curve and the oscillation amplitude used for the measurement. Recently, a test was proposed by Sader et al. [Nat. Nanotechnol. 13, 1088 (2018)] to determine whether a given deconvolution is well-posed for a specific amplitude. Here, we experimentally validate this test by means of two experimental situations measured with a set of different amplitudes: force–distance spectra over a single carbon monoxide molecule as well as over a Fe trimer on Cu(111). We verify the validity of the test by showing that for a given experimental situation, a specific amplitude may result in a well-posed deconvolution while a different amplitude might result in an ill-posed result. Furthermore, we comment on typical pitfalls that are caused by the discrete nature of experimental data and provide MATLAB code that can be used by everyone to perform this test with their own data.
Lithium-electrolyte solvation and reaction in the electrolyte of a lithium ion battery: A ReaxFF reactive force field study
Authors: Hossain Md Jamil , Pawar Gorakh , Liaw Boryann , Gering Kevin L. , Dufek Eric J. , van Duin Adri C. T.
Published: May 2020

In the electrode/electrolyte interface of a typical lithium-ion battery, a solid electrolyte interphase layer is formed as a result of electrolyte decomposition during the initial charge/discharge cycles. Electron leakage from the anode to the electrolyte reduces the Li+-ion and makes it more reactive, resulting in decomposition of the organic electrolyte. To study the Li-electrolyte solvation, solvent exchange, and subsequent solvent decomposition reactions at the anode/electrolyte interface, we have extended the existing ReaxFF reactive force field parameter sets to organic electrolyte species, such as ethylene carbonate, ethyl methyl carbonate, vinylene carbonate, and LiPF6 salt. Density Functional Theory (DFT) data describing Li-associated initiation reactions for the organic electrolytes and binding energies of Li-electrolyte solvation structures were generated and added to the existing ReaxFF training data, and subsequently, we trained the ReaxFF parameters with the aim of finding the optimal reproduction of the DFT data. In order to discern the characteristics of the Li neutral and cation, we have introduced a second Li parameter set to describe the Li+-ion. ReaxFF is trained for Li-neutral and Li+-cation to have similar solvation energies, but unlike the neutral Li, Li+ will not induce reactivity in the organic electrolyte. Solvent decomposition reactions are presumed to happen once Li+-ions are reduced to Li-atoms, which can be simulated using a Monte Carlo type atom modification within ReaxFF. This newly developed force field is capable of distinguishing between a Li-atom and a Li+-ion properly. Moreover, it is found that the solvent decomposition reaction barrier is a function of the number of ethylene carbonate molecules solvating the Li-atom.
Rectification and separation of mixtures of active and passive particles driven by temperature difference
Authors: Zhu Wei-jing , Li Teng-Chao , Zhong Wei-rong , Ai Bao-quan
Published: May 2020

Transport and separation of binary mixtures of active and passive particles are investigated in the presence of temperature differences. It is found that temperature differences can strongly affect the rectification and separation of the mixtures. For active particles, there exists an optimal temperature difference at which the rectified efficiency is maximal. Passive particles are not propelled and move by collisions with active particles, so the response to temperature differences is more complicated. By changing the system parameters, active particles can change their directions, while passive particles always move in the same direction. The simulation results show that the separation of mixtures is sensitive to the system parameters, such as the angular velocity, the temperature difference, and the polar alignment. The mixed particles can be completely separated under certain conditions.
Magnetic sensitivity of the microwave cryogenic sapphire oscillator
Authors: Giordano Vincent , Fluhr Christophe , Dubois Benoit
Published: May 2020

The Cryogenic Sapphire Oscillator (CSO) is today recognized for its unprecedented frequency stability, mainly coming from the exceptional physical properties of its resonator made in a high-quality sapphire crystal. With these instruments, the fractional frequency measurement resolution, currently of the order of 10−16, is such that it is possible to detect very small phenomena such as residual resonator environmental sensitivities. Thus, we highlighted an unexpected magnetic sensitivity of the CSO at low magnetic fields. The fractional frequency sensitivity has been preliminarily evaluated to be 10−13/G, making this phenomenon a potential cause of frequency stability limitations. In this paper, we report the experimental data related to the magnetic sensitivity of the quasi-transverse magnetic Whispering Gallery (WGH) modes excited in sapphire crystals differing from their paramagnetic contaminant concentration. The magnetic behavior of the WGH modes does not follow the expected theory combining the Curie law and the Zeeman effect affecting the electron spin resonance of the paramagnetic ions present in the crystal.
Not in the mood
Authors: Giancaspro David
Published: May 2020

Previous studies (e.g., van Osch & Sleeman 2016; Perez-Cortes 2016) have found that heritage speakers (HSs) of Spanish produce less lexically-selected subjunctive mood morphology than Spanish-dominant speakers. It remains unclear, however, whether the HSs’ tendency to produce less subjunctive mood than Spanish-dominant speakers is attributable to representational differences (e.g., Montrul 2002, 2008), input quality differences (e.g., Pires & Rothman 2009; Pascual y Cabo & Rothman 2012), or as yet unidentified factors. The present study addresses this question by testing the effect of lexical frequency on advanced proficiency HSs’ productive (Experiment 1) and receptive (Experiment 2) knowledge of lexically-selected subjunctive mood in Spanish. Results of Experiments 1 and 2 indicate that advanced proficiency HSs are both (a) highly accurate with subjunctive mood and yet also (b) significantly less accurate with lower frequency verbs. Given these findings, as well as the categorical subjunctive production of the Spanish-dominant bilingual control group, it is argued that HSs’ differences from dominant speakers may be (partially) attributable to gaps in lexical, rather than morphosyntactic knowledge.
How do parental input and socio-economic status account for differences within and between the cohorts?
Authors: Montanari Elke G. , Abel Roman , Tschudinovski Lilia , Graßer Barbara
Published: May 2020

How does vocabulary in the heritage language develop? Does the social environment of the community have an influence? This chapter presents empirical results regarding the development of expressive and receptive vocabulary in the heritage language and analyzes the effects of amount of exposure, use, socio-economic status, dominance, and community on the acquisition of vocabulary in the heritage language. A Russian-German and a Turkish-German speaking sample are compared: 211 children at the age of 6–10 years were tested with a standardized picture naming task in a cross-sectional design. The results show a good receptive mastery and a limited expressive command of vocabulary with large individual differences, and only a slight development in the timespan of four years. Between the communities we find systematic variation, which we attribute to social and pragmatic differences with moderator and mediator effects. Possible limitations of the results are discussed with respect to cross-linguistic test effects.
Heritage and non-heritage bilinguals
Authors: Andreou Maria , Dosi Ifigenia , Papadopoulou Despina , Tsimpli Ianthi Maria
Published: May 2020

The present study explores the effects of literacy support in the languages of the bilingual child on the linguistic and cognitive skills of (non-)heritage speakers. 70 children speaking Albanian (L1) and Greek (L2) are divided into three groups according to whether they receive literacy support in their L1, L2 or in both languages. To test the children's proficiency in Greek, we used an expressive vocabulary task, two working memory tasks, a non-verbal intelligence task and a sentence repetition task (SRT). The findings suggest that good levels of biliteracy established through bilingual education positively influence the child’s linguistic and cognitive performance. Furthermore, the lack of working memory effects on the children’s SRT performance emphasizes the importance of biliteracy development and its educational support, which together with vocabulary knowledge contribute to bilingual development.
Safety Assessment of Electromagnetic Exposure in High-Speed Train Carriage with Full Passengers
Authors: Tian Rui , Lu Mai
Published: May 2020

The objective of this work is to evaluate the safety of the electromagnetic environment in the carriage of high-speed trains exposed to power cables when the train is full of passengers. The electromagnetic model of a real carriage, two sets of power cables and the 84 passengers were set up by using COMSOL Multiphysics software based on CRH5. The distributions of induced electric and magnetic fields in the carriage, inside and on the surface of passengers were investigated. The results show that the induced electric and magnetic fields on the windows are greater than on the passengers and the max value of induced magnetic field is 2627.10 µT, and the max value of induced electric field is 2.0 × 105 mV m−1. The maximum values of the induced electric and magnetic fields in 84 passengers’ brain tissues were obtained, and it was found that the maximum values occurred in the third row passengers. The distribution of induced electric and magnetic fields at the cross-section of passengers’ heads in the third row was also obtained, and we found that the passengers at the window side were greater than those of aisle passengers. In the third row, the maximum values of the induced electric and magnetic fields in the head of two passengers near the window were 94.6 mV m−1, 90.9 µT, 96.3 mV m−1, and 90.4 µT, respectively. We also found the all data were below the ICNIRP Reference Levels, which indicates the electromagnetic exposure caused by power cables when the train is full of passengers will not threat passengers’ health.
Computationally predicting binding affinity in protein–ligand complexes: free energy-based simulations and machine learning-based scoring functions
Authors: Wang Debby D , Zhu Mengxu , Yan Hong
Published: May 2020

Accurately predicting protein–ligand binding affinities can substantially facilitate the drug discovery process, but it remains as a difficult problem. To tackle the challenge, many computational methods have been proposed. Among these methods, free energy-based simulations and machine learning-based scoring functions can potentially provide accurate predictions. In this paper, we review these two classes of methods, following a number of thermodynamic cycles for the free energy-based simulations and a feature-representation taxonomy for the machine learning-based scoring functions. More recent deep learning-based predictions, where a hierarchy of feature representations are generally extracted, are also reviewed. Strengths and weaknesses of the two classes of methods, coupled with future directions for improvements, are comparatively discussed.
Prediction of cancer driver genes through network-based moment propagation of mutation scores
Authors: Gumpinger Anja C , Lage Kasper , Horn Heiko , Borgwardt Karsten
Published: May 2020

Motivation

Gaining a comprehensive understanding of the genetics underlying cancer development and progression is a central goal of biomedical research. Its accomplishment promises key mechanistic, diagnostic and therapeutic insights. One major step in this direction is the identification of genes that drive the emergence of tumors upon mutation. Recent advances in the field of computational biology have shown the potential of combining genetic summary statistics that represent the mutational burden in genes with biological networks, such as protein–protein interaction networks, to identify cancer driver genes. Those approaches superimpose the summary statistics on the nodes in the network, followed by an unsupervised propagation of the node scores through the network. However, this unsupervised setting does not leverage any knowledge on well-established cancer genes, a potentially valuable resource to improve the identification of novel cancer drivers.

Results

We develop a novel node embedding that enables classification of cancer driver genes in a supervised setting. The embedding combines a representation of the mutation score distribution in a node’s local neighborhood with network propagation. We leverage the knowledge of well-established cancer driver genes to define a positive class, resulting in a partially labeled dataset, and develop a cross-validation scheme to enable supervised prediction. The proposed node embedding followed by a supervised classification improves the predictive performance compared with baseline methods and yields a set of promising genes that constitute candidates for further biological validation.

Availability and implementation

Code available at https://github.com/BorgwardtLab/MoProEmbeddings.

Supplementary information

Supplementary data are available at Bioinformatics online.
Metaviral
SPAdes: assembly of viruses from metagenomic data
Authors: Antipov Dmitry , Raiko Mikhail , Lapidus Alla , Pevzner Pavel A
Published: May 2020

Motivation

Although the set of currently known viruses has been steadily expanding, only a tiny fraction of the Earth’s virome has been sequenced so far. Shotgun metagenomic sequencing provides an opportunity to reveal novel viruses but faces the computational challenge of identifying viral genomes that are often difficult to detect in metagenomic assemblies.

Results

We describe a MetaviralSPAdes tool for identifying viral genomes in metagenomic assembly graphs that is based on analyzing variations in the coverage depth between viruses and bacterial chromosomes. We benchmarked MetaviralSPAdes on diverse metagenomic datasets, verified our predictions using a set of virus-specific Hidden Markov Models and demonstrated that it improves on the state-of-the-art viral identification pipelines.

Availability and implementation

Metaviral SPAdes includes ViralAssembly, ViralVerify and ViralComplete modules that are available as standalone packages: https://github.com/ablab/spades/tree/metaviral_publication, https://github.com/ablab/viralVerify/ and https://github.com/ablab/viralComplete/.

Contact

d.antipov@spbu.ru

Supplementary information

Supplementary data are available at Bioinformatics online.
HALPER facilitates the identification of regulatory element orthologs across species
Authors: Zhang Xiaoyu , Kaplow Irene M , Wirthlin Morgan , Park Tae Yoon , Pfenning Andreas R
Published: May 2020

Diverse traits have evolved through cis-regulatory changes in genome sequence that influence the magnitude, timing and cell type-specificity of gene expression. Advances in high-throughput sequencing and regulatory genomics have led to the identification of regulatory elements in individual species, but these genomic regions remain difficult to align across taxonomic orders due to their lack of sequence conservation relative to protein coding genes. The groundwork for tracing the evolution of regulatory elements is provided by the recent assembly of hundreds of genomes, the generation of reference-free Cactus multiple sequence alignments of these genomes, and the development of the halLiftover tool for mapping regions across these alignments. We present halLiftover Post-processing for the Evolution of Regulatory Elements (HALPER), a tool for constructing contiguous regulatory element orthologs from the outputs of halLiftover. We anticipate that this tool will enable users to efficiently identify orthologs of regulatory elements across hundreds of species, providing novel insights into the evolution of traits that have evolved through gene expression.

Availability and implementation

HALPER is implemented in python and available on github: https://github.com/pfenninglab/halLiftover-postprocessing.

Supplementary information

Supplementary data are available at Bioinformatics online.
Polyadenylation of mRNA as a novel regulatory mechanism of gene expression in temporal lobe epilepsy
Authors: Parras Alberto , de Diego-Garcia Laura , Alves Mariana , Beamer Edward , Conte Giorgia , Jimenez-Mateos Eva M , Morgan James , Ollà Ivana , Hernandez-Santana Yasmina , Delanty Norman , Farrell Michael A , O’Brien Donncha F , Ocampo Alejandro , Henshall David C , Méndez Raúl , Lucas José J , Engel Tobias
Published: May 2020

Temporal lobe epilepsy is the most common and refractory form of epilepsy in adults. Gene expression within affected structures such as the hippocampus displays extensive dysregulation and is implicated as a central pathomechanism. Post-transcriptional mechanisms are increasingly recognized as determinants of the gene expression landscape, but key mechanisms remain unexplored. Here we show, for first time, that cytoplasmic mRNA polyadenylation, one of the post-transcriptional mechanisms regulating gene expression, undergoes widespread reorganization in temporal lobe epilepsy. In the hippocampus of mice subjected to status epilepticus and epilepsy, we report >25% of the transcriptome displays changes in their poly(A) tail length, with deadenylation disproportionately affecting genes previously associated with epilepsy. Suggesting cytoplasmic polyadenylation element binding proteins (CPEBs) being one of the main contributors to mRNA polyadenylation changes, transcripts targeted by CPEBs were particularly enriched among the gene pool undergoing poly(A) tail alterations during epilepsy. Transcripts bound by CPEB4 were over-represented among transcripts with poly(A) tail alterations and epilepsy-related genes and CPEB4 expression was found to be increased in mouse models of seizures and resected hippocampi from patients with drug-refractory temporal lobe epilepsy. Finally, supporting an adaptive function for CPEB4, deletion of Cpeb4 exacerbated seizure severity and neurodegeneration during status epilepticus and the development of epilepsy in mice. Together, these findings reveal an additional layer of gene expression regulation during epilepsy and point to novel targets for seizure control and disease-modification in epilepsy.
Coronavirus Disease 2019 (COVID-19) Clinical Trial Oversight at a Major Academic Medical Center: Approach of Michigan Medicine
Authors: Spector-Bagdady Kayte , Higgins Peter D R , Aaronson Keith D , Birk Judy , Flaherty Kevin R , Gregg Kevin S , Hyzy Robert C , Kaul Daniel R , Lauring Adam S , Magee John C , Meurer William J , Park Pauline K , Scott Phillip , Lok Anna S
Published: May 2020

Clinicians, eager to offer the best care in the absence of guiding data, have provided patients with coronavirus disease 2019 (COVID-19) diverse clinical interventions. This usage has led to perceptions of efficacy of some interventions that, while receiving media coverage, lack robust evidence. Moving forward, randomized controlled clinical trials are necessary to ensure that clinicians can treat patients effectively during this outbreak and the next. To do so, academic medical centers must address 2 key research issues: (1) how to effectively and efficiently determine which trials have the best chance of benefiting current and future patients and (2) how to establish a transparent and ethical process for subject recruitment while maintaining research integrity and without overburdening patients or staff. We share here the current methods used by Michigan Medicine to address these issues.
Is the propensity to emit alarm calls associated with health status?
Authors: Nash Austin L , Jebb Alexandra H M , Blumstein Daniel T
Published: May 2020

The production and structure of animal signals may depend on an individual’s health status and may provide more than one type of information to receivers. While alarm calls are not typically viewed as health condition dependent, recent studies have suggested that their structure, and possibly their propensity to be emitted, depends on an individual’s health condition and state. We asked whether the propensity of yellow-bellied marmots (Marmota flaviventer) to emit calls is influenced by their immunological or parasite status, by quantifying both trap-elicited and natural calling rates as a function of their neutrophil-to-lymphocyte (NL) ratio, the presence of a blood borne trypanosome, and the presence of several intestinal parasites (Eimeria sp., Entamoeba sp., and Ascaris sp.). We fitted mixed effects models to determine if the health measures we collected were associated with the probability of calling in a trap and with annual rates of natural alarm calling. Marmots infected with a blood-borne trypanosome were marginally more likely to call naturally and when trapped, while those infected with the intestinal parasite Ascaris were less likely to call when trapped. NL ratio was not directly associated with in-trap calling probability, but males were more likely to call when they had higher NL ratios. Thus, health conditions, such as parasite infection and immune system activation, can modulate the production of alarm signals and potentially provide information to both predators and prey about the caller’s condition. Playback experiments are required to confirm if receivers use such information.
Fool Me Once: An Experiment on Credibility and Leadership
Authors: Cooper David J , Hamman John R , Weber Roberto A
Published: May 2020

We investigate ‘social credibility’, a leader’s ability to convince followers that conditions are favourable and that others will follow the leader's advice. To do so, we study an experimental joint venture with three key properties: returns are uncertain, investments are complements, and investment is often more beneficial for the leader than the followers. The leader has private information about investment returns and can facilitate coordination through cheap-talk recommendations. We find that leaders manage social credibility by forgoing potentially profitable advice to invest, increasing the likelihood that subsequent recommendations are followed. We identify factors that affect the persistence of social credibility.
Trends in substance use and primary prevention variables among adolescents in Lithuania, 2006–19
Authors: Asgeirsdottir Bryndis Bjork , Kristjansson Alfgeir Logi , Sigfusson Jon , Allegrante John P , Sigfusdottir Inga Dora
Published: May 2020

Background

Since the implementation of the Icelandic Model for Primary Prevention of Substance Use in Iceland (IPM), substance use has decreased steadily among 14–16-year-old adolescents and primary prevention factors have improved. Although the IPM is being implemented in several other regions around the world, information documenting its effectiveness in other country contexts is lacking. This study assessed trends in substance use and primary prevention variables in three cities in Lithuania following the implementation of the IPM.

Methods

Data collected from repeated, comparative cross-sectional self-report surveys conducted among a total of 30 572 10th graders in the cities of Kaunas, Klaipeda and Vilnius, Lithuania, from 2006 to 2019, were analyzed. Cochran–Armitage test for linear trend and analysis of variance for linear trend was used to assess time-trends in prevalence of substance use and mean levels of primary prevention variables over time.

Results

Following the implementation of IPM rates of cigarette smoking and the use of alcohol, cannabis and amphetamine has decreased among 10th graders in Lithuania’s three largest cities and simultaneously preventive variables targeted have improved. Similar to Iceland, primary prevention variables were related to substance use in the expected direction, with the exception of organized sports participation, which was not associated with less likelihood of alcohol, cannabis and amphetamine use.

Conclusion

Trends in substance use and primary prevention variables following the implementation of the IPM are similar in the three cities in Lithuania as in Iceland. Further research is needed to better understand the mechanisms underlying these trends.
Global warming shifts the composition of the abundant bacterial phyllosphere microbiota as indicated by a cultivation-dependent and -independent study of the grassland phyllosphere of a long-term warming field experiment
Authors: Aydogan Ebru L , Budich Olga , Hardt Martin , Choi Young Hae , Jansen-Willems Anne B , Moser Gerald , Müller Christoph , Kämpfer Peter , Glaeser Stefanie P
Published: May 2020

The leaf-colonizing bacterial microbiota was studied in a long-term warming experiment on a permanent grassland, which had been continuously exposed to increased surface temperature (+2°C) for more than six years. Two abundant plant species, Arrhenatherum elatius and Galium album, were studied. Surface warming reduced stomata opening and changed leaf metabolite profiles. Leaf surface colonization and the concentration of leaf-associated bacterial cells were not affected. However, bacterial 16S ribosomal RNA (rRNA) gene amplicon Illumina sequencing showed significant temperature effects on the plant species-specific phyllosphere microbiota. Warming partially affected the concentrations of cultured bacteria and had a significant effect on the composition of most abundant cultured plant species-specific bacteria. The abundance of Sphingomonas was significantly reduced. Sphingomonas isolates from warmed plots represented different phylotypes, had different physiological traits and were better adapted to higher temperatures. Among Methylobacterium isolates, a novel phylotype with a specific mxaFtype was cultured from plants of warmed plots while the most abundant phylotype cultured from control plots was strongly reduced. This study clearly showed a correlation of long-term surface warming with changes in the plant physiology and the development of a physiologically and genetically adapted phyllosphere microbiota.
Residual lattice strain in quartzites as a potential palaeo-piezometer
Authors: Wenk Hans-Rudolf , Chandler Brian Chase , Chen Kai , Li Yao , Tamura Nobumichi , Yu Rong
Published: May 2020

If a crystal lattice is subjected to a stress, it becomes distorted and no longer represents the ideal crystal symmetry, and if the stress introduces defects such as dislocations, some of this distortion is preserved after the applied stress is removed. In this study, we investigate lattice distortion in quartz at the micron scale with synchrotron X-ray Laue diffraction. From Laue images the local deviatoric strain tensor is derived and corresponding stresses are calculated based on elastic properties. The method is applied to metasedimentary quartzites from the Bergell Alps that were deformed at conditions of greenschist facies metamorphism. The residual palaeostrain is represented in maps of the deviatoric strain tensor components and with deviatoric strain axis pole figures. Data suggest overall shortening perpendicular to the schistosity plane but with considerable asymmetry relative to foliation and lineation, probably attributed to simple shear. Crystallographic pole figures from Laue diffraction agree with neutron diffraction and EBSD measurements and display quartz c-axes girdle distributions with maxima also perpendicular to schistosity. The method shows promise to be used as a palaeo-piezometer to unravel the stress field during tectonic deformation.
So, What is White Hat Hacking?
Authors: Hamilton Johanna
Published: May 2020

Justin Shaw Grey, Sales Director of Synack, spoke to Johanna Hamilton AMBCS about the competitive world of international pen-testing, finding vulnerabilities in programs and selling the concept of white hat hacking to a company board.
Planning For a Pandemic
Authors: McConnell Patrick
Published: May 2020

Business continuity planning (BCP) and related IT disaster recovery planning (IT DRP) have become established, respected and important disciplines in business. However, many of the assumptions underlying BCP/DRP planning today will NOT hold in a pandemic, writes technology risk expert Dr Patrick McConnell FBCS CITP CEng.
11 Ways to Stop Misinformation
Authors: Cooper Martin
Published: May 2020

Following the wrong advice in these difficult times could be dangerous. Martin Cooper MBCS RIT Tech looks at 11 ways we can all help to combat the rising tide of misinformation on the web.
What's Wrong With Our Technology?
Authors: Fish Ian
Published: May 2020

When thinking about this issue’s theme in the context of cyber security, it became quite difficult to determine what might be the ‘glass half full’ scenarios… writes Ian Fish, Chair of the Information Security Specialist Group.
How to Choose the Right Supplier
Authors: Taylor Paul
Published: May 2020

All organisations employ third-party suppliers, which means supplier selection is now a key organisational capability, writes Paul Taylor MBCS, author, speaker and mentor. To effectively select the right partners, follow this ‘four lensed’ approach.
Formalising Medical Informatics
Authors: Penketh Claire
Published: May 2020

James Freed, Chief Information Officer for Health Education England and Deputy CEO for Building a Digital Ready Work Force, talks to Claire Penketh, Senior Press Officer at BCS.
Rapid implementation of a COVID-19 remote patient monitoring program
Authors: Annis Tucker , Pleasants Susan , Hultman Gretchen , Lindemann Elizabeth , Thompson Joshua A , Billecke Stephanie , Badlani Sameer , Melton Genevieve B
Published: May 2020

Objective

The study sought to evaluate early lessons from a remote patient monitoring engagement and education technology solution for patients with coronavirus disease 2019 (COVID-19) symptoms.

Materials and Methods

A COVID-19–specific remote patient monitoring solution (GetWell Loop) was offered to patients with COVID-19 symptoms. The program engaged patients and provided educational materials and the opportunity to share concerns. Alerts were resolved through a virtual care workforce of providers and medical students.

Results

Between March 18 and April 20, 2020, 2255 of 3701 (60.93%) patients with COVID-19 symptoms enrolled, resulting in over 2303 alerts, 4613 messages, 13 hospital admissions, and 91 emergency room visits. A satisfaction survey was given to 300 patient respondents, 74% of whom would be extremely likely to recommend their doctor.

Discussion

This program provided a safe and satisfying experience for patients while minimizing COVID-19 exposure and in-person healthcare utilization.

Conclusions

Remote patient monitoring appears to be an effective approach for managing COVID-19 symptoms at home.
The tradeoffs between safety and alert fatigue: Data from a national evaluation of hospital medication-related clinical decision support
Authors: Co Zoe , Holmgren A Jay , Classen David C , Newmark Lisa , Seger Diane L , Danforth Melissa , Bates David W
Published: May 2020

Objective

The study sought to evaluate the overall performance of hospitals that used the Computerized Physician Order Entry Evaluation Tool in both 2017 and 2018, along with their performance against fatal orders and nuisance orders.

Materials and Methods

We evaluated 1599 hospitals that took the test in both 2017 and 2018 by using their overall percentage scores on the test, along with the percentage of fatal orders appropriately alerted on, and the percentage of nuisance orders incorrectly alerted on.

Results

Hospitals showed overall improvement; the mean score in 2017 was 58.1%, and this increased to 66.2% in 2018. Fatal order performance improved slightly from 78.8% to 83.0% (P < .001), though there was almost no change in nuisance order performance (89.0% to 89.7%; P = .43). Hospitals alerting on one or more nuisance orders had a 3-percentage-point increase in their overall score.

Discussion

Despite the improvement of overall scores in 2017 and 2018, there was little improvement in fatal order performance, suggesting that hospitals are not targeting the deadliest orders first. Nuisance order performance showed almost no improvement, and some hospitals may be achieving higher scores by overalerting, suggesting that the thresholds for which alerts are fired from are too low.

Conclusions

Although hospitals improved overall from 2017 to 2018, there is still important room for improvement for both fatal and nuisance orders. Hospitals that incorrectly alerted on one or more nuisance orders had slightly higher overall performance, suggesting that some hospitals may be achieving higher scores at the cost of overalerting, which has the potential to cause clinician burnout and even worsen safety.
Effect of the Timing of Antiretroviral Treatment Initiation on Outcomes in Children Living With Human Immunodeficiency Virus Admitted With Severe Acute Malnutrition
Authors: Archary Moherndran , Sartorius Benn , La Russa Philip , Sibaya Thobekile , Healy Micheal , Bobat Raziya A
Published: May 2020

Background

Delays in early infant diagnosis and antiretroviral treatment (ART) initiation in developing countries frequently result in malnutrition at initial presentation with associated higher mortality and delayed immune recovery. The optimal timing of ART initiation is yet to be established.

Methods

Eighty-two children admitted with HIV and severe acute malnutrition (SAM) between July 2012 and December 2015 were enrolled. Patients were randomized to initiate ART within 14 days from admission (early arm) or delay ART initiation until nutritional recovery and >14 days after admission (delayed arm). All patients received a standardized treatment and feeding protocol and were followed to 48 weeks.

Results

The mean age of the patients at baseline was 23.3 months (standard deviation [SD], 27.9; range, 1.6–129 months). The mean time from admission to ART initiation was 5.6 days (SD, 4.4) in the early arm and 23 days (SD, 5.8) in the delayed arm (P < .001). There was no significant difference in mortality (P = .62), virologic response (P = .53), and anthropometric response (P = .57) between the 2 groups at 48 weeks. However, the rates of change in CD4, viral load, weight for age z score, and height for age z score occurred earlier and favored the delayed arm at early time points but were not significant at 24 and 48 months.

Conclusions

Despite initial improved responses in the delayed arm, lack of difference in outcome at 48 weeks supports a pragmatic approach with earlier ART initiation in children living with HIV admitted with SAM.

In this randomised controlled study of ART initiation in children admitted with HIV and severe acute malnutrition (SAM), despite initial improved responses in the delayed arm, lack of difference in outcome at 48 weeks supports a pragmatic approach with earlier ART initiation in children living with HIV admitted with SAM.

Clinical Trials Registration

PACTR 21609001751384.
In vitropharmacokinetics/pharmacodynamics modeling and efficacy against systemic candidiasis inDrosophila melanogasterof a bisaryloxypropanamine derivative
Authors: Dalla Lana Daiane Flores , Kaminski Taís Fernanda Andrzejewski , Lavorato Stefânia Neiva , Merkel Simone , Zanette Régis Adriel , da Rosa Priscila Dallé , Staudt Keli Jaqueline , de Araújo Bibiana Verlindo , da Costa Bárbara , Quatrin Priscilla Maciel , Bazana Luana Candice Genz , Ferreira Felipe Alves , Caurio Cássia Ferreira Braz , de Andrade Saulo Fernandes , Alves Ricardo José , Fuentefria Alexandre Meneghello
Published: May 2020

The number of deaths due to systemic fungal infections is increasing alarmingly, which is aggravated by the limitations of traditional treatments and multidrug resistance. Therefore, the research and development of new therapeutic options against pathogenic fungi is an urgent need. To evaluate the fungicidal activity of a synthetic compound, 1,3-bis-(3,4-dichlorophenoxy)propan-2-aminium chloride (2j), through time-kill studies and pharmacokinetics/pharmacodynamics (PK/PD) modeling. The protective effect of the compound was also evaluated using the Drosophila melanogaster minihost model of candidiasis. Mathematical modeling of time-kill data of compound 2j was performed to obtain PD characteristics. Additionally, Toll-deficient D. melanogaster flies were infected with a Candida albicans strain and treated with 2j. We observed that compound 2j demonstrated a time- and dose-dependent fungicidal effect against Candida spp. and dermatophytes, even at low concentrations, and rapidly achieved kill rates reaching the maximum effect in less than one hour. The efficacy of the compound against systemic candidiasis in D. melanogaster flies was comparable to that achieved by fluconazole. These results support the potential of compound 2j as a systemic antifungal agent candidate and serve as a starting point for further studies involving mammalian animal models.
Powering central compact objects with a tangled crustal magnetic field
Authors: Gourgouliatos Konstantinos N , Hollerbach Rainer , Igoshev Andrei P
Published: May 2020

Central Compact Objects (CCOs) are X-ray sources with luminosity ranging between 1032 and 1034 erg s−1, located at the centres of supernova remnants. Some of them have been confirmed to be neutron stars. Timing observations have allowed the estimation of their dipole magnetic field, placing them in the range ∼1010–1011 G. The decay of their weak dipole fields, mediated by the Hall effect and Ohmic dissipation, cannot provide sufficient thermal energy to power their X-ray luminosity, as opposed to magnetars whose X-ray luminosities are comparable. Motivated by the question of producing high X-ray power through magnetic field decay while maintaining a weak dipole field, we explore the evolution of a crustal magnetic field that does not consist of an ordered axisymmetric structure, but rather comprises a tangled configuration. This can be the outcome of a non-self-excited dynamo, buried inside the crust by fallback material following the supernova explosion. We find that such initial conditions lead to the emergence of the magnetic field from the surface of the star and the formation of a dipolar magnetic field component. An internal tangled magnetic field of the order of 1014 G can provide sufficient Ohmic heating to the crust and power CCOs, while the dipole field it forms is approximately 1010 G, as observed in CCOs.
SDSS-IV MaNGA: Excavating the fossil record of stellar populations in spiral galaxies
Authors: Peterken Thomas , Merrifield Michael , Aragón-Salamanca Alfonso , Fraser-McKelvie Amelia , Avila-Reese Vladimir , Riffel Rogério , Knapen Johan , Drory Niv
Published: May 2020

We perform a ‘fossil record’ analysis for ≈800 low-redshift spiral galaxies, using starlight applied to integral field spectroscopic observations from the SDSS-IV MaNGA survey to obtain fully spatially resolved high-resolution star formation histories (SFHs). From the SFHs, we are able to build maps indicating the present-day distribution of stellar populations of different ages in each galaxy. We find small negative mean age gradients in most spiral galaxies, especially at high stellar mass, which reflects the formation times of stellar populations at different galactocentric radii. We show that the youngest (<108.5 yr) populations exhibit significantly more extended distributions than the oldest (>109.5 yr), again with a strong dependence on stellar mass. By interpreting the radial profiles of ‘time slices’ as indicative of the size of the galaxy at the time those populations had formed, we are able to trace the simultaneous growth in mass and size of the spiral galaxies over the last 10 Gyr. Despite finding that the evolution of the measured light-weighted radius is consistent with inside-out growth in the majority of spiral galaxies, the evolution of an equivalent mass-weighted radius has changed little over the same time period. Since radial migration effects are likely to be small, we conclude that the growth of discs in spiral galaxies has occurred predominantly through an inside-out mode (with the effect greatest in high-mass galaxies), but this has not had anywhere near as much impact on the distribution of mass within spiral galaxies.
A roadmap to hadronic supercriticalities: a comprehensive study of the parameter space for high-energy astrophysical sources
Authors: Mastichiadis Apostolos , Florou Ioulia , Kefala Elina , Boula Stella S , Petropoulou Maria
Published: May 2020

Hadronic supercriticalities are radiative instabilities that appear when large amounts of energy are stored in relativistic protons. When the proton energy density exceeds some critical value, a runaway process is initiated resulting in the explosive transfer of the proton energy into electron–positron pairs and radiation. The runaway also leads to an increase of the radiative efficiency, namely the ratio of the photon luminosity to the injected proton luminosity. We perform a comprehensive study of the parameter space by investigating the onset of hadronic supercriticalities for a wide range of source parameters (i.e. magnetic field strengths of 1 G−100 kG and radii of 1011−1016 cm) and maximum proton Lorentz factors (103−109). We show that supercriticalities are possible for the whole range of source parameters related to compact astrophysical sources, like gamma-ray bursts and cores and jets of active galactic nuclei. We also provide an in-depth look at the physical mechanisms of hadronic supercriticalities and show that magnetized relativistic plasmas are excellent examples of non-linear dynamical systems in high-energy astrophysics.
Onthe changes in the physical properties of the ionized region around the Weigelt structures in η Carinae over the 5.54-yr spectroscopic cycle
Authors: Teodoro M , Gull T R , Bautista M A , Hillier D J , Weigelt G , Corcoran M F
Published: May 2020

We present HST/STIS observations and analysis of two prominent nebular structures around the central source of η Carinae, the knots C and D. The former is brighter than the latter for emission lines from intermediate- or high-ionization potential ions. The brightness of lines from intermediate- and high-ionization potential ions significantly decreases at phases around periastron. We do not see conspicuous changes in the brightness of lines from low-ionization potential (<13.6 eV) ions over the orbital period. Line ratios suggest that the total extinction towards the Weigelt structures is AV = 2.0. Weigelt C and D are characterized by an electron density of 106.9 cm−3 that does not significantly change throughout the orbital cycle. The electron temperature varies from 5500 (around periastron) to 7200 K (around apastron). The relative changes in the brightness of the He i lines are well reproduced by the variations in the electron temperature alone. We found that, at phases around periastron, the electron temperature seems to be higher for Weigelt C than that of D. The Weigelt structures are located close to the Homunculus equatorial plane, at a distance of about 1240 au from the central source. From the analysis of proper motion and age, the Weigelt complex can be associated with the equatorial structure called ‘Butterfly Nebula’ surrounding the central binary system.