bluuebunny/crossref_metadata_2025 huggingface dataset:
(4+1)-Cycloadditions Exploiting the Biphilicity of Oxyphosphonium Enolates and RhII/PdII-Stabilized Metallocarbenes for the Construction of Five-Membered Frameworks
Authors: Ashfeld Brandon L. , Tucker Zachary D.
Published: January 2021

(4+1)-Cyclizations are an underutilized disconnect for the formation of five-membered heterocyclic and carbocyclic frameworks. Herein we analyze methods employing oxyphosphonium enolates and RhII/PdII-metallocarbenes as C1 synthons in the presence of several four-atom components for the synthesis of 2,3-dihydrobenzofurans, 2,3-dihydroindoles, oxazolones, cyclopentenones, and pyrrolones.

1 Introduction

2 (4+1)-Cyclizations Employing Kukhtin–Ramirez-Like Reactivity

3 (4+1)-Cyclizations Employing a Cyclopropanation/Ring-Expansion Sequence

4 Pd-Catalyzed (4+1)-Cyclizations through Carbene Migratory Insertion/Reductive Elimination Processes

5 Summary
Synthesis of Functionalized 9-Substituted Fluorene Derivatives via Boron Trifluoride Catalysed Reaction of Coplanar 9-(Phenylethynyl)-9H-fluoren-9-ols, Aryl Aminoamides and N-Bromosuccinimide
Authors: Shanmugam Ponnusamy , Athira Mohanakumaran
Published: January 2021

A boron trifluoride catalysed reaction of coplanar 9-(phenyl­ethynyl)-9H-fluoren-9-ols with various 2-aminobenzamides affords a number of highly functionalized, conjugated (Z)-2-((2-(9H-fluoren-9-ylidene)-1-phenylethylidene)amino) benzamides in excellent yield. The reaction in the presence of N-bromosuccinimide affords (E)-5-bromo-2-((2-bromo-2-(9H-fluoren-9-ylidene)-1-phenylethylidene)amino)benz­amides in very good yields. The scope of the reaction is demonstrated by selecting N-aryl substituted 2-aminobenzamides and aminosulfonamides as reaction partners. The structures of representative compounds were established by single-crystal XRD analysis. Based on the structure of the products, a plausible mechanism via formation of allene carbocation intermediates is proposed.
Double perspective in the Colonial present
Authors: Svalastog Anna Lydia , Wilson Shawn , Gaski Harald , Senior Kate , Chenhall Richard
Published: January 2021

This paper will explain the concept ofdouble perspectiveand the impact that this cultural understanding may have on the health of the Indigenous peoples of Scandinavia. In inter-cultural communication, one set of meanings may be discernible to the outsider while a whole extra set of restricted or underlying meanings are only accessible for those people who have the cultural knowledge to discern them. These different sets of meanings embody a double perspective. It is not dual perspectives on the same reality but rather seeing two separate but overlapping realities. We will discuss the layers of meaning which are involved in the interactions between public healthcare institutions, clinicians and staff, and Indigenous people including the Sámi. These interactions are influenced by the impact of colonization and the ongoing epistemicide of Indigenous thought. By realising the improved resilience that a double perspective brings to Indigenous peoples, an awareness of the inclusion and exclusion of Indigenous persons, cultures and histories should become established in public institutions and in everyday life. A double perspective carries Sámi resilience, and should be understood as a key to support individual health, and also the collective wellbeing of a people living on their traditional yet colonized land.
Estimation of pulsatile energy dissipation in intersecting pipe junctions using inflow pulsatility indices
Authors: Rasooli Reza , Dur Onur , Pekkan Kerem
Published: January 2021

This study aims to characterize the effect of inflow pulsatility on the hydrodynamic power loss inside intersecting double-inlet, double-outlet pipe intersection (DIPI) with cross-flow mixing. An extensive set of computational fluid dynamics (CFD) simulations was performed in order to identify the individual effects of flow pulsatility parameters, i.e., amplitude, frequency, and relative phase shift between the inflow waveform oscillations, on power loss. An experimentally validated second order accurate solver is employed in this study. To predict the pulsatile flow performance of any given arbitrary inflow waveforms, we proposed three easy-to-calculate pulsatility indices. The frequency-coupled quasi-steady flow theory is incorporated to identify the functional form of pulsatile power loss as a function of these indices. Our results indicated that the power loss within the inflow branch sections, lumped outflow-junction section, and the whole conduit correlates strongly with the pulsatility of each inflow waveform, the total inflow pulsatility, and inflow frequency content, respectively. The complete CFD simulation matrix provided a unified analytical expression that predicts pulsatile power loss inside a one-degree offset DIPI geometry. The predictive accuracy of this expression is evaluated in comparison to the CFD evaluation of arbitrary multi-harmonic inflow waveforms. These results have important implications on hydrodynamic pipe networks that employ complex junctions as well as in the patient-to-patient comparison of surgically created vascular connections. Coupling the present analytical pulsatile power loss expression with non-dimensional steady power loss formulation provided a valuable predictive tool to estimate the pulsatile energy dissipation for any arbitrary junction geometry with minimum use of the costly CFD computations.
Subwavelength acoustic energy harvesting via topological interface states in 1D Helmholtz resonator arrays
Authors: Zhao Degang , Chen Xincheng , Li Pan , Zhu Xue-Feng
Published: January 2021

We have theoretically and experimentally demonstrated subwavelength acoustic energy harvesting via topological interface states in 1D Helmholtz resonator arrays. The system can produce two types of bandgaps in the subwavelength realm due to the resonance and band folding mechanism, respectively. Through the analyses of the Zak phase and eigenfield distributions, the topological properties of band-folding-induced gaps can be changed by tuning the lattice structural parameters, while those of resonant gaps maintain stability. When two different arrays are spliced together, topological interface states will appear in the band-folding-induced band gaps but do not exist in the resonant gaps. The experimental measurements agree well with the theoretical prediction. Our study expands the applicability of acoustic topological insulators in a compacted platform.
A cylindrical SiC heater for an externally heated diamond anvil cell to 1500 K
Authors: Okuda Yoshiyuki , Kimura Seiji , Ohta Kenji , Park Yohan , Wakamatsu Tatsuya , Mashino Izumi , Hirose Kei
Published: January 2021

Semiconductor-based heaters for diamond anvil cells (DACs) have advantages over metal wire heaters in terms of repeated use and the ability to reach higher temperatures. We introduce a cylindrical SiC heater for an externally heated DAC (EHDAC) that works satisfactorily at temperatures up to 1500 K and pressures around 90 GPa. The heater is reusable and inexpensive, and only slight modifications to the DAC are required to fit the heater. Experiments on melting of NaCl and gold are conducted at ambient pressure to test the temperature accuracy of the EHDAC system, and resistance measurements on iodine at high pressures and temperatures are performed to assess the heater assembly. These test runs show that a uniform and accurate temperature can be maintained by the EHDAC assembly, which has potential applications to a variety of transport property measurements.
An accessible microwave cavity experiment for plasma density determination
Authors: Oliveira J , Hachmeister D , Lourenço P D , Brotankova J , Fernandes H
Published: January 2021

Plasmas are indissociable from microwave science. Effectively, the most fundamental properties of any plasma arise from its plasma frequency. However, combining plasma physics with electromagnetic (EM) wave propagation is challenging for physics students. An EM cavity poses an excellent opportunity to understand the behavior of EM standing waves, the issues related to transmitted and reflected power in waveguides, coupling, and how free charges in the plasma affect its resonant frequency and quality factor, interlinking the properties of matter with wave propagation. The inclusion of an external magnetic field allows students to explore the underlying principles of magnetic confinement in a linear geometry.
Anomalous diffusion, nonergodicity, and ageing for exponentially and logarithmically time-dependent diffusivity: striking differences for massive versus massless particles
Authors: Cherstvy Andrey G , Safdari Hadiseh , Metzler Ralf
Published: January 2021

We investigate a diffusion process with a time-dependent diffusion coefficient, both exponentially increasing and decreasing in time,

D
(
t
)
=

D
0

e

±
2
α
t

. For this (hypothetical) nonstationary diffusion process we compute—both analytically and from extensive stochastic simulations—the behavior of the ensemble- and time-averaged mean-squared displacements (MSDs) of the particles, both in the over- and underdamped limits. Simple asymptotic relations derived for the short- and long-time behaviors are shown to be in excellent agreement with the results of simulations. The diffusive characteristics in the presence of ageing are also considered, with dramatic differences of the over- versus underdamped regime. Our results for

D
(
t
)
=

D
0

e

±
2
α
t

extend and generalize the class of diffusive systems obeying scaled Brownian motion featuring a power-law-like variation of the diffusivity with time,

D
(
t
)
∼

t

α
−
1

. We also examine the logarithmically increasing diffusivity,

D
(
t
)
=

D
0

log
[
t
/

τ
0

]

, as another fundamental functional dependence (in addition to the power-law and exponential) and as an example of diffusivity slowly varying in time. One of the main conclusions is that the behavior of the massive particles is predominantly ergodic, while weak ergodicity breaking is repeatedly found for the time-dependent diffusion of the massless particles at short times. The latter manifests itself in the nonequivalence of the (both nonaged and aged) MSD and the mean time-averaged MSD. The current findings are potentially applicable to a class of physical systems out of thermal equilibrium where a rapid increase or decrease of the particles’ diffusivity is inherently realized. One biological system potentially featuring all three types of time-dependent diffusion (power-law-like, exponential, and logarithmic) is water diffusion in the brain tissues, as we thoroughly discuss in the end.
Investigating the energetic and entropic components of effective potentials across a glass transition
Authors: Szukalo Ryan J , Noid W G
Published: January 2021

By eliminating unnecessary details, coarse-grained (CG) models provide the necessary efficiency for simulating scales that are inaccessible to higher resolution models. However, because they average over atomic details, the effective potentials governing CG degrees of freedom necessarily incorporate significant entropic contributions, which limit their transferability and complicate the treatment of thermodynamic properties. This work employs a dual-potential approach to consider the energetic and entropic contributions to effective interaction potentials for CG models. Specifically, we consider one- and three-site CG models for ortho-terphenyl (OTP) both above and below its glass transition. We employ the multiscale coarse-graining (MS-CG) variational principle to determine interaction potentials that accurately reproduce the structural properties of an all-atom (AA) model for OTP at each state point. We employ an energy-matching variational principle to determine an energy operator that accurately reproduces the intra- and inter-molecular energy of the AA model. While the MS-CG pair potentials are almost purely repulsive, the corresponding pair energy functions feature a pronounced minima that corresponds to contacting benzene rings. These energetic functions then determine an estimate for the entropic component of the MS-CG interaction potentials. These entropic functions accurately predict the MS-CG pair potentials across a wide range of liquid state points at constant density. Moreover, the entropic functions also predict pair potentials that quite accurately model the AA pair structure below the glass transition. Thus, the dual-potential approach appears a promising approach for modeling AA energetics, as well as for predicting the temperature-dependence of CG effective potentials.
Self-diffusion of nonspherical particles fundamentally conflicts with effective sphere models
Authors: Roosen-Runge Felix , Schurtenberger Peter , Stradner Anna
Published: January 2021

Modeling diffusion of nonspherical particles presents an unsolved and considerable challenge, despite its importance for the understanding of crowding effects in biology, food technology and formulation science. A common approach in experiment and simulation is to map nonspherical objects on effective spheres to subsequently use the established predictions for spheres to approximate phenomena for nonspherical particles. Using numerical evaluation of the hydrodynamic mobility tensor, we show that this so-called effective sphere model fundamentally fails to represent the self-diffusion in solutions of ellipsoids as well as rod-like assemblies of spherical beads. The effective sphere model drastically overestimates the slowing down of self-diffusion down to volume fractions below 0.01. Furthermore, even the linear term relevant at lower volume fraction is inaccurate, linked to a fundamental misconception of effective sphere models. To overcome the severe problems related with the use of effective sphere models, we suggest a protocol to predict the short-time self-diffusion of rod-like systems, based on simulations with hydrodynamic interactions that become feasible even for more complex molecules as the essential observable shows a negligible system-size effect.
The phase diagram of Ti-6Al-4V at high-pressures and high-temperatures
Authors: MacLeod S G , Errandonea D , Cox G A , Cynn H , Daisenberger D , Finnegan S E , McMahon M I , Munro K A , Popescu C , Storm C V
Published: January 2021

We report results from a series of diamond-anvil-cell synchrotron x-ray diffraction and large-volume-press experiments, and calculations, to investigate the phase diagram of commercial polycrystalline high-strength Ti-6Al-4V alloy in pressure–temperature space. Up to ∼30 GPa and 886 K, Ti-6Al-4V is found to be stable in the hexagonal-close-packed, or α phase. The effect of temperature on the volume expansion and compressibility of α–Ti-6Al-4V is modest. The martensitic α → ω (hexagonal) transition occurs at ∼30 GPa, with both phases coexisting until at ∼38–40 GPa the transition to the ω phase is completed. Between 300 K and 844 K the α → ω transition appears to be independent of temperature. ω–Ti-6Al-4V is stable to ∼91 GPa and 844 K, the highest combined pressure and temperature reached in these experiments. Pressure–volume–temperature equations-of-state for the α and ω phases of Ti-6Al-4V are generated and found to be similar to pure Ti. A pronounced hysteresis is observed in the ω–Ti-6Al-4V on decompression, with the hexagonal structure reverting back to the α phase at pressures below ∼9 GPa at room temperature, and at a higher pressure at elevated temperatures. Based on our data, we estimate the Ti-6Al-4V α–β–ω triple point to occur at ∼900 K and 30 GPa, in good agreement with our calculations.
A NIST facility for resonant soft x-ray scattering measuring nano-scale soft matter structure at NSLS-II
Authors: Gann Eliot , Crofts Thomas , Holland Glenn , Beaucage Peter , McAfee Terry , Kline R Joseph , Collins Brian A , McNeill Christopher R , Fischer Daniel A , DeLongchamp Dean M
Published: January 2021

We present the design and performance of a polarized resonant soft x-ray scattering (RSoXS) station for soft matter characterization built by the national institute of standards and technology at the national synchrotron light source-II (NSLS-II). The RSoXS station is located within the spectroscopy soft and tender beamline suite at NSLS-II located in Brookhaven national laboratory, New York. Numerous elements of the RSoXS station were designed for optimal performance for measurements on soft matter systems, where it is of critical importance to minimize beam damage and maximize collection efficiency of polarized x-rays. These elements include a novel optical design, sample manipulator and sample environments, as well as detector setups. Finally, we will report the performance of the measurement station, including energy resolution, higher harmonic content and suppression methods, the extent and mitigation of the carbon absorption dip on optics, and the range of polarizations available from the elliptically polarized undulator source.
Physical processes determining plasma confinement in tokamaks with transport barriers from the point of view of self-organization
Authors: Razumova K A , Andreev V F , Eliseev L G , Kantor M Y , Kasyanova N V , Lysenko S E , Melnikov A V
Published: January 2021

The goal of this article is to describe processes linked to energy confinement in tokamak plasmas from the perspective of self-organization—the main process that determines the behavior of turbulent plasmas. In the paper Razumova et al 2020 Plasma Phys. Rep.
46 337, such an analysis was performed for regimes without transport barriers. The present paper extends this approach to regimes with barriers and magnetic islands. In a shorter version, it was presented in Razumova et al 2020 Entropy
22 53, which showed that the appearance of islands in the inner part of the barrier is directly related to the formation of the barrier and limits its growth. We discuss the structure of the radial heat flux that carries energy from the plasma in such a way that the pressure profile remains close to the self-consistent profile (as observed in the experiment).
Method for estimating the frequency-wavenumber resolved power spectrum density using the maximum entropy method for limited spatial points
Authors: Kobayashi T , Nishizawa T , Sasaki M , Yoshinuma M , Ida K
Published: January 2021

A combination of the Fourier transform and the maximum entropy method for estimating the frequency-wavenumber resolved power spectrum density is proposed. After illustrating the physical insight of the maximum entropy method by using synthetic test data, capability of the proposed method is tested using numerical simulation data. The method is also applied to experimental data obtained by the beam emission spectroscopy in the Large Helical Device. All of those examinations show that the proposed method provides more plausible results than conventional methods when the available spatial points are limited.
‘What does professional curiosity mean to you?’: an exploration of professional curiosity in probation
Authors: Phillips Jake , Ainslie Sam , Fowler Andrew , Westaby Chalen
Published: January 2021

This article explores the concept of professional curiosity in relation to probation practice. We synthesise existing relevant literature to develop a theoretical framework of how professional curiosity is understood, arguing that professional curiosity can be used to manage risk, develop the therapeutic alliance, and facilitate knowledge building. We then present analysis of how the concept has been used in probation policy and analyse data generated in the first study of professional curiosity amongst probation workers in England and Wales. We conduct a content analysis of the meanings that probation staff (n = 445) attribute to the term professional curiosity by analysing responses to an open-ended question, which asked participants ‘What does professional curiosity mean to you?’. Our analysis is exploratory in nature and sheds some light on how probation workers in England and Wales understand professional curiosity. Respondents were more likely to associate the term with managing risk, although there is considerable heterogeneity between the way it is understood. We draw on existing research about probation training, culture and values to explore the reasons for these findings. We conclude by considering the limitations of the research and highlighting policy implications.
Symptoms of traumatic encephalopathy syndrome are common in the US general population
Authors: Iverson Grant L , Gardner Andrew J
Published: January 2021

There are no validated criteria for diagnosing chronic traumatic encephalopathy, or traumatic encephalopathy syndrome, in a living person. The purpose of this study is to examine symptom reporting resembling the research criteria for traumatic encephalopathy syndrome in men and women from the US general population. This is a retrospective analysis of publicly available data from a cross-sectional epidemiological study. The National Comorbidity Survey Replication was designed to examine the prevalence and correlates of mental disorders in the USA. The study included a nationally representative sample of 9282 adults (4139 men and 5143 women). An in-person interview and survey were conducted in the homes of men and women from the general population. The study was conducted with participants residing in New York City, Los Angeles, Chicago, Philadelphia, Detroit, San Francisco, Washington DC, Dallas/Fort Worth, Houston, Boston, Nassau-Suffolk NY, St. Louis, Pittsburgh, Baltimore, Minneapolis and Atlanta. Symptoms from the research criteria for the diagnosis of traumatic encephalopathy syndrome were applied to men and women in the general population and in sub-groups of people with health problems and mental health problems. A small percentage of the US general population met symptom criteria for traumatic encephalopathy syndrome (6.6–11.9%, depending on the definition applied). People with chronic pain were much more likely to meet criteria (i.e. 14.8–30.5%), and two out of three people who have experienced suicidality in the past year met symptom criteria for traumatic encephalopathy syndrome (65.2–72.2%). The majority of women with a mood disorder and chronic pain met criteria (62.7–89.8%). This is the largest study, to date, examining the aspects of the research criteria for the diagnosis of traumatic encephalopathy syndrome in the general population, and the first study to examine these criteria in women. This study has important clinical and public health implications. The potential rate for misdiagnosing traumatic encephalopathy syndrome in adults who are experiencing chronic pain, idiopathic mental health problems or both is high.
Diminished Cortical Excitation and Elevated Inhibition During Perceptual Impairments in a Mouse Model of Autism
Authors: Del Rosario Joseph , Speed Anderson , Arrowood Hayley , Motz Cara , Pardue Machelle , Haider Bilal
Published: January 2021

Sensory impairments are a core feature of autism spectrum disorder (ASD). These impairments affect visual perception and have been hypothesized to arise from imbalances in cortical excitatory and inhibitory activity. There is conflicting evidence for this hypothesis from several recent studies of transgenic mouse models of ASD; crucially, none have measured activity from identified excitatory and inhibitory neurons during simultaneous impairments of sensory perception. Here, we directly recorded putative excitatory and inhibitory population spiking in primary visual cortex (V1) while simultaneously measuring visual perceptual behavior in CNTNAP2−/− knockout (KO) mice. We observed quantitative impairments in the speed, accuracy, and contrast sensitivity of visual perception in KO mice. During these perceptual impairments, stimuli evoked more firing of inhibitory neurons and less firing of excitatory neurons, with reduced neural sensitivity to contrast. In addition, pervasive 3–10 Hz oscillations in superficial cortical layers 2/3 (L2/3) of KO mice degraded predictions of behavioral performance from neural activity. Our findings show that perceptual deficits relevant to ASD may be associated with elevated cortical inhibitory activity along with diminished and aberrant excitatory population activity in L2/3, a major source of feedforward projections to higher cortical regions.
Eradication of Staphylococcus aureus Post-Sternotomy Mediastinitis Following the Implementation of Universal Preoperative Nasal Decontamination With Mupirocin: An Interrupted Time-Series Analysis
Authors: San-Juan Rafael , Gotor-Pérez Consuelo Alejandra , López-Medrano Francisco , Fernández-Ruiz Mario , Lora David , Lizasoain Manuel , Silva José Tiago , Ruiz-Ruigómez María , Corbella Laura , Rodríguez-Goncer Isabel , Viedma Esther , Orellana María Angeles , Renes Carreño Emilio , Pérez-Vela José Luis , Benito-Arnaiz Victoria , López-Gude María Jesús , Cortina-Romero José María , Aguado José María
Published: January 2021

Background

Although presurgical nasal decontamination with mupirocin (NDM) has been advocated as a measure for preventing postsurgical mediastinitis (PSM) due to Staphylococcus aureus, this strategy is not universally recommended due to lack of robust supporting evidence. We aimed to evaluate the role of preoperative NDM in the annual incidence of S. aureus PSM at our institution.

Methods

An interrupted time-series analysis, with an autoregressive error model, was applied to our single-center cohort by comparing preintervention (1990–2003) and postintervention (2005–2018) periods. Logistic regression was performed to analyze risk factors for S. aureus PSM.

Results

12 236 sternotomy procedures were analyzed (6370 [52.1%] and 5866 [47.9%] in the pre- and postintervention periods, respectively). The mean annual percentage adherence to NDM estimated over the postintervention period was 90.2%. Only 4 of 127 total cases of S. aureus PSM occurred during the 14-year postintervention period (0.68/1000 sternotomies vs 19.31/1000 in the preintervention period; P < .0001). Interrupted time-series analysis demonstrated a statistically significant annual reduction in S. aureus PSM of –9.85 cases per 1000 sternotomies (−13.17 to −6.5; P < .0001) in 2005, with a decreasing trend maintained over the following 5 years and an estimated relative reduction of 84.8% (95% confidence interval [CI], 89.25–74.09%). Chronic obstructive pulmonary disease was the single independent risk factor for S. aureus PSM (odds ratio, 3.7; 95% CI, 1.72–7.93) and was equally distributed in patients undergoing sternotomy during pre- or postintervention periods.

Conclusions

Our experience suggests the implementation of preoperative NDM significantly reduces the incidence of S. aureus PSM.
Establishment of a new sex-determining allele driven by sexually antagonistic selection
Authors: Sakamoto Takahiro , Innan Hideki
Published: January 2021

The turnover of sex-determining loci has repeatedly occurred in a number of species, rather than having a diverged pair of sex chromosomes. We model the turnover process by considering a linked locus under sexually antagonistic selection. The entire process of a turnover may be divided into two phases, which are referred to as the stochastic and deterministic phases. The stochastic phase is when a new sex-determining allele just arises and is still rare and random genetic drift plays an important role. In the deterministic phase, the new allele further increases in frequency by positive selection. The theoretical results currently available are for the deterministic phase, which demonstrated that a turnover of a newly arisen sex-determining locus could benefit from selection at a linked locus under sexually antagonistic selection, by assuming that sexually antagonistic selection works in a form of balancing selection. In this work, we provide a comprehensive theoretical description of the entire process from the stochastic phase to the deterministic phase. In addition to balancing selection, we explore several other modes of selection on the linked locus. Our theory allows us make a quantitative argument on the rate of turnover and the effect of the mode of selection at the linked locus. We also performed simulations to explore the pattern of polymorphism around the new sex-determining locus. We find that the pattern of polymorphism is informative to infer how selection worked through the turnover process.
Insights from the reanalysis of high-throughput chemical genomics data for Escherichia coli K-12
Authors: Wu Peter I-Fan , Ross Curtis , Siegele Deborah A , Hu James C
Published: January 2021

Despite the demonstrated success of genome-wide genetic screens and chemical genomics studies at predicting functions for genes of unknown function or predicting new functions for well-characterized genes, their potential to provide insights into gene function has not been fully explored. We systematically reanalyzed a published high-throughput phenotypic dataset for the model Gram-negative bacterium Escherichia coli K-12. The availability of high-quality annotation sets allowed us to compare the power of different metrics for measuring phenotypic profile similarity to correctly infer gene function. We conclude that there is no single best method; the three metrics tested gave comparable results for most gene pairs. We also assessed how converting quantitative phenotypes to discrete, qualitative phenotypes affected the association between phenotype and function. Our results indicate that this approach may allow phenotypic data from different studies to be combined to produce a larger dataset that may reveal functional connections between genes not detected in individual studies.
Genome analysis ofPlectus murrayi, a nematode from continental Antarctica
Authors: Xue Xia , Suvorov Anton , Fujimoto Stanley , Dilman Adler R , Adams Byron J
Published: January 2021

Plectus murrayi is one of the most common and locally abundant invertebrates of continental Antarctic ecosystems. Because it is readily cultured on artificial medium in the laboratory and highly tolerant to an extremely harsh environment, P. murrayi is emerging as a model organism for understanding the evolutionary origin and maintenance of adaptive responses to multiple environmental stressors, including freezing and desiccation. The de novo assembled genome of P. murrayi contains 225.741 million base pairs and a total of 14,689 predicted genes. Compared to Caenorhabditis elegans, the architectural components of P. murrayi are characterized by a lower number of protein-coding genes, fewer transposable elements, but more exons, than closely related taxa from less harsh environments. We compared the transcriptomes of lab-reared P. murrayi with wild-caught P. murrayi and found genes involved in growth and cellular processing were up-regulated in lab-cultured P. murrayi, while a few genes associated with cellular metabolism and freeze tolerance were expressed at relatively lower levels. Preliminary comparative genomic and transcriptomic analyses suggest that the observed constraints on P. murrayi genome architecture and functional gene expression, including genome decay and intron retention, may be an adaptive response to persisting in a biotically simplified, yet consistently physically harsh environment.
Using a genetic algorithm to optimize a data-limited catch rule
Authors: Fischer Simon H , De Oliveira José A A , Mumford John D , Kell Laurence T
Published: January 2021

Many data-limited fish stocks worldwide require management advice. Simple empirical management procedures have been used to manage data-limited fisheries but do not necessarily ensure compliance with maximum sustainable yield objectives and precautionary principles. Genetic algorithms are efficient optimization procedures for which the objectives are formalized as a fitness function. This optimization can be included when testing management procedures in a management strategy evaluation. This study explored the application of a genetic algorithm to an empirical catch rule and found that this approach could substantially improve the performance of the catch rule. The optimized parameterization and the magnitude of the improvement were dependent on the specific stock, stock status, and definition of the fitness function. The genetic algorithm proved to be an efficient and automated method for tuning the catch rule and removed the need for manual intervention during the optimization process. Therefore, we conclude that the approach could also be applied to other management procedures, case-specific tuning, and even data-rich stocks. Finally, we recommend the phasing out of the current generic ICES “2 over 3” advice rule in favour of case-specific catch rules of the form tested here, although we caution that neither works well for fast-growing stocks.
Microdrop Human Immunodeficiency Virus Sequencing for Incidence and Drug Resistance Surveillance
Authors: Park Sung Yong , Faraci Gina , Murphy Gary , Pilcher Christopher , Busch Michael P , Lee Ha Youn
Published: January 2021

Background

Precise and cost-efficient human immunodeficiency virus (HIV) incidence and drug resistance surveillances are in high demand for the advancement of the 90-90-90 “treatment for all” target.

Methods

We developed microdrop HIV sequencing for the HIV incidence and drug resistance assay (HIDA), a single-blood-draw surveillance tool for incidence and drug resistance mutation (DRM) detection. We amplified full-length HIV envelope and pol gene sequences within microdroplets, and this compartmental amplification with long-read high-throughput sequencing enabled us to recover multiple unique sequences.

Results

We achieved greater precision in determining the stage of infection than current incidence assays, with a 1.2% false recency rate (proportion of misclassified chronic infections) and a 262-day mean duration of recent infection (average time span of recent infection classification) from 83 recently infected and 81 chronically infected individuals. Microdrop HIV sequencing demonstrated an increased capacity to detect minority variants and linked DRMs. By screening all 93 World Health Organization surveillance DRMs, we detected 6 pretreatment drug resistance mutations with 2.6%–13.2% prevalence and cross-linked mutations.

Conclusions

HIDA with microdrop HIV sequencing may promote global HIV real-time surveillance by serving as a precise and high-throughput cross-sectional survey tool that can be generalized for surveillance of other pathogens.
Incorporating realistic trait physiology into crop growth models to support genetic improvement
Authors: Boote K J , Jones J W , Hoogenboom G
Published: January 2021

In silico plant modelling is the use of dynamic crop simulation models to evaluate hypothetical plant traits (phenology, processes and plant architecture) that will enhance crop growth and yield for a defined target environment and crop management (weather, soils, limited resource). To be useful for genetic improvement, crop models must realistically simulate the principles of crop physiology responses to the environment and the principles by which genetic variation affects the dynamic crop carbon, water and nutrient processes. Ideally, crop models should have sufficient physiological detail of processes to incorporate the genetic effects on these processes to allow for robust simulations of response outcomes in different environments. Yield, biomass, harvest index, flowering date and maturity are emergent outcomes of many interacting genes and processes rather than being primary traits directly driven by singular genetics. Examples will be given for several grain legumes, using the CSM-CROPGRO model, to illustrate emergent outcomes simulated as a result of single and multiple combinations of genotype-specific parameters and to illustrate genotype by environment interactions that may occur in different target environments. Specific genetically influenced traits can result in G × E interactions on crop growth and yield outcomes as affected by available water, CO2 concentration, temperature, and other factors. An emergent outcome from a given genetic trait may increase yield in one environment but have little or negative effect in another environment. Much work is needed to link genetic effects to the physiological processes for in silico modelling applications, especially for plant breeding under future climate change.
Treatment of methicillin-resistant Staphylococcus aureus (MRSA): updated guidelines from the UK
Authors: Brown Nicholas M , Brown Erwin M ,   the Guideline Development Group, Brown Nicholas M , Goodman Anna L , Horner Carolyne , Jenkins Abi , Brown Erwin M
Published: January 2021

The UK guidelines for the treatment of infections caused by MRSA have been updated and are published in JAC-Antimicrobial Resistance. The update reviews new evidence published since the previous UK guidelines were published over 10 years ago. It includes evidence relating to antimicrobial agents that have been licensed since then for the treatment of Gram-positive bacterial infections including MRSA. It also considers the impact on treatment of the changing epidemiology of MRSA in the UK, especially relating to circulating community strains. A striking finding from the current literature review was the paucity of good quality evidence. The current guidelines therefore represent a hybrid of varying degrees of evidence and expert opinion. Where there was no new published evidence, we have retained some of the existing recommendations. We were unable to find strong evidence of the superior efficacy of newer agents compared with that of vancomycin.
Case series of intradural disc in recurrence of lumbar disc prolapse
Authors: Alhani Bashar , Nagappa Satish , Baird Charles , Botchu Rajesh , Hughes Simon , Mehta Jewalant , Hassan Faizul
Published: January 2021

Intradural disc herniation is a rare entity reported at 0.04–1.1% that occurs most commonly in the lumbar spine particularly at L4–L5 region.

There is a paucity of literature due to the rarity of this condition. Intradural disc herniations must be considered in the differential diagnosis of prolapsed intervertebral disc disease especially with recent worsening of symptoms and mismatch of unenhanced magnetic resonance induction (MRI) findings. The confirmation is made with intraoperative findings.

An intradural disc herniation is most often diagnosed intraoperatively. Contrast enhanced MRI scan is mandatory for pre-operative diagnosis.

We report on two cases presenting to our unit in the form of recurrent intradural disc disease following previous lumbar surgery occurring within 3 months of the index procedure in both cases.
A Novel Application of Head Tracking Data in the Analysis and Assessment of Operational Cervical Spine Range of Motion for Army Aviators
Authors: Williams Steven T , Madison Adrienne M , Brozoski Frederick T , Chancey Valeta Carol
Published: January 2021

Introduction

Neck pain among rotary-wing aviators has been established as an important issue in the military community, yet no U.S. Army regulation defines exactly what cervical spine range of motion (CROM) is adequate for flight. This lack of regulation leaves flight surgeons to subjectively determine whether an aviator affected by limited CROM is fit to maintain flight status. The U.S. Army Aeromedical Research Laboratory is conducting a study among AH-64 and UH-60 pilots to define CROM requirements in simulated and actual flight using optical head tracking equipment. Presented here is a preliminary analysis of head position data from a pilot and co-pilot in two AH-64 missions.

Methods

Maintenance data recorder (MDR) files from two AH-64 missions were provided by the Apache Attack Helicopter Project Management Office. Data were filtered down to three-dimensional pilot and co-pilot head position data and each data point was analyzed to determine neck posture. These neck postures were then categorized as neutral, mild, and severe for flexion/extension, lateral bending, and twist rotation postural categories.

Results

Twist rotation postures reached 90 degrees, particularly early in the flight; additionally, a few instances of 90-degree lateral bends were observed. Co-pilots spent more time than pilots in mild and severe twist rotation posture for both flights. Co-pilots also spend a high percentage of time in mild flexion and twist rotation.

Conclusion

This investigation provides a proof of concept for analysis of head tracking data from MDR files as a surrogate measure of neck posture in order to estimate CROM requirements in rotary-wing military flight missions. Future studies will analyze differences in day and night flights, pilot versus co-pilot CROM, and neck movement frequency.
Antimicrobial and Hemostatic Activities of Cotton-Based Dressings Designed to Address Prolonged Field Care Applications
Authors: Edwards J Vincent , Prevost Nicolette , Yager Dorne , Nam Sunghyun , Graves Elena , Santiago Michael , Condon Brian , Dacorta Joseph
Published: January 2021

Introduction

Developing affordable and effective hemostatic and antimicrobial wound dressings for prolonged field care (PFC) of open wounds is of interest to prevent infection, to prevent sepsis, and to conserve tissue viability. The need for an effective hemostatic dressing that is also antimicrobial is required of a hemostatic dressing that can be left in place for extended periods (days). This is particularly important in light of the existence of pathogens that have coagulopathy properties. Thus, dressings that provide effective hemostasis and reduction in the frequency of dressing changes, whereas exerting robust antimicrobial activity are of interest for PFC. Highly cleaned and sterile unbleached cotton has constituents not found in bleached cotton that are beneficial to the hemostatic and inflammatory stages of wound healing. Here, we demonstrate two approaches to cotton-based antimicrobial dressings that utilize the unique components of the cotton fiber with simple modification to confer a high degree of hemostatic and antimicrobial efficacy.

Methods

Spun bond nonwoven unbleached cotton was treated using traditional pad dry cure methods to add ascorbic acid, zeolite (NaY) with pectin, calcium chloride, and sodium carbonate/calcium chloride. Similarly, nanosilver-embedded cotton fiber was blended with pristine cotton fibers at various weight ratios to produce hydroentangled nonwoven fabrics. The resulting treated fabrics were assessed for hemostasis using thromboelastographic clotting assays and antimicrobial activity utilizing American Association of Textile Chemists and Colorists 100.

Results

Zeolite-containing dressings possessed significant hemostatic activity, whereas ascorbic acid- and silver-containing dressings reduced Gram-positive and Gram-negative organism numbers by several logs.

Conclusion

Based on this study, a multilayered hemostatic dressing with antimicrobial properties is envisioned. This dressing would be safe, would be economical, and have a stable shelf-life that would be conducive for using PFC.
Identification and Assessment of Plasmodium berghei Merozoites and Cell Cycle by Flow Cytometry
Authors: Li Qigui , Xie Lisa H , Zhang Jing , Pybus Brandon S
Published: January 2021

Background

The asexual blood stages of the Plasmodium berghei life cycle including merozoites are attractive targets for transmission blocking vaccines and drugs. Improved understanding of P. berghei life cycle stage growth and development would provide new opportunities to evaluate antimalarial vaccines and drugs.

Methods

Blood stage samples from C57BL/6 albino mice infected with P. berghei sporozoites were singly stained with a high binding affinity deoxyribonucleic acid dye, YOYO-1, and measured by flow cytometry (FCM). Duplicate slides were made from samples and stained with diluted Giemsa’s and YOYO-1, respectively. Correlated results were compared by FCM, light microscopy, and fluorescent microscopy.

Results

Complete life cycle stage determination and analysis by FCM is reported to include merozoites, ring forms, trophozoites, immature, and mature schizonts. FCM demonstrated a clear separation between each stage using their unique fluorescence distribution. When compared to light microscopy, a strong correlation (r 2 = 0.925 to 0.974) was observed in determining the ring forms, trophozoites, and schizonts phases, but only a moderate correlation (r 2 = 0.684 to 0.778) was observed for merozoites. The identification and measurement of merozoites suggest that FCM is a useful technique to monitor the entire life stage of the parasite. Initial stage-specific data demonstrated that mefloquine has a mode of action on mature parasite forms, and artesunic acid was rapidly effective against merozoites and other immature and mature parasite forms with higher killing.

Conclusion

Blood stage parasites in each individual life stage, including merozoites, are reliably identified and quantified quickly by FCM, making this technique an ideal alternative to microscopy. This integrated whole life stage model, particularly with confirmed determination of merozoite population, could widely be used for drug and vaccine research in malaria therapy and prophylaxis.
Evolution of First Aid Training in the British Army
Authors: Bricknell Martin C M , Hodgetts Brigadier T J
Published: January 2021

Introduction

This article describes the evolution of first aid in the British Army from the Crimean War to the present day in order to interpret the processes of innovation, implementation, and diffusion of ideas to improve the clinical outcomes for military casualties.

Materials and Methods

The article is an analysis of policy and practice for training in first aid published in King’s/Queen’s Regulations for the Army, the Field Service Pocket Book, or generic military training policy. This is complimented by a review of medical training manuals and a search of articles in the Journal of the Royal Army Medical Corps (RAMC). Most sources have been accessed from the Museum of Military of Medicine and the Wellcome RAMC Muniments Collection.

Results

The narrative summarizes the evolution of clinical concepts in first aid and their translation for Army personnel; starting with RAMC stretcher bearers, extended to soldiers assigned to medical duties at unit level, and finally simplified into first aid training to be taught to all soldiers. Alongside this story of training is a secondary story of the development of field first aid equipment, principally dressings, tourniquets, and analgesia. The final part of the story is the transfer of knowledge from military first aid training into the civilian, community setting. The following themes were identified: the reality of conflict wounds, battlefield first aid is different from civilian first aid, progressive transfer of training from medics to soldiers, transfer of knowledge to civilian sector and internationally, and specific clinical innovations: first field dressings, tourniquets, and prehospital analgesia.

Discussion

The current generation of soldiers are at the highest ever standard of first aid training and equipment. This must be maintained through gathering of evidence in effectiveness and outcomes in prehospital emergency care in both military and civilian settings.