bluuebunny/crossref_metadata_2025 huggingface dataset:
The solar nebula origin of (486958) Arrokoth, a primordial contact binary in the Kuiper Belt
Authors: McKinnon W. B. , Richardson D. C. , Marohnic J. C. , Keane J. T. , Grundy W. M. , Hamilton D. P. , Nesvorný D. , Umurhan O. M. , Lauer T. R. , Singer K. N. , Stern S. A. , Weaver H. A. , Spencer J. R. , Buie M. W. , Moore J. M. , Kavelaars J. J. , Lisse C. M. , Mao X. , Parker A. H. , Porter S. B. , Showalter M. R. , Olkin C. B. , Cruikshank D. P. , Elliott H. A. , Gladstone G. R. , Parker J. Wm. , Verbiscer A. J. , Young L. A. ,   the New Horizons Science Team
Published: February 2020

Examining Arrokoth

The New Horizons spacecraft flew past the Kuiper Belt object (486958) Arrokoth (also known as 2014 MU
69
) in January 2019. Because of the great distance to the outer Solar System and limited bandwidth, it will take until late 2020 to downlink all the spacecraft's observations back to Earth. Three papers in this issue analyze recently downlinked data, including the highest-resolution images taken during the encounter (see the Perspective by Jewitt). Spencer
et al.
examined Arrokoth's geology and geophysics using stereo imaging, dated the surface using impact craters, and produced a geomorphological map. Grundy
et al.
investigated the composition of the surface using color imaging and spectroscopic data and assessed Arrokoth's thermal emission using microwave radiometry. McKinnon
et al.
used simulations to determine how Arrokoth formed: Two gravitationally bound objects gently spiraled together during the formation of the Solar System. Together, these papers determine the age, composition, and formation process of the most pristine object yet visited by a spacecraft.

Science
, this issue p.
eaay3999
, p.
eaay3705
, p.
eaay6620
; see also p.
980
Transcription factor AP2 controls cnidarian germ cell induction
Authors: DuBuc Timothy Q. , Schnitzler Christine E. , Chrysostomou Eleni , McMahon Emma T. , Febrimarsa  , Gahan James M. , Buggie Tara , Gornik Sebastian G. , Hanley Shirley , Barreira Sofia N. , Gonzalez Paul , Baxevanis Andreas D. , Frank Uri
Published: February 2020

Conserved gene specifies germ cell

Germ cells are the exclusive progenitors of gametes. In most studied animals, including humans, germ cells are produced only once during embryogenesis and are not replenished in adult life. DuBuc
et al.
studied germ cell induction in the clonal cnidarian
Hydractinia symbiolongicarpus
, an animal that forms germ cells continuously in adult life from stem cells that also generate somatic cells. A single transcription factor is capable of converting the animal's adult stem cells to germ cells. A similar gene also controls germ cell induction in mammalian embryos, but its action there is limited to a single event in early embryogenesis.

Science
, this issue p.
757
Ionoelastomer junctions between polymer networks of fixed anions and cations
Authors: Kim Hyeong Jun , Chen Baohong , Suo Zhigang , Hayward Ryan C.
Published: February 2020

Ionic elastomeric material electronics

Wearable devices often need to be soft or flexible, and ideally, these properties would extend beyond packaging material to also include the electronics. Some soft ionic conductors have been made in the form of flexible, stretchable, and transparent devices, but leaks from these materials is a concern. Kim
et al.
demonstrate ionic elastomeric diodes and transistors that harness ionic double layers to rectify and switch ionic currents (see the Perspective by Gao and Lee). This is achieved without trapped liquids by fixing the anions or cations to an elastomer network while the other species of ions remain mobile.

Science
, this issue p.
773
; see also p.
735
Twisted bulk-boundary correspondence of fragile topology
Authors: Song Zhi-Da , Elcoro Luis , Bernevig B. Andrei
Published: February 2020

Understanding fragile topology

Exploiting topological features in materials is being pursued as a route to build in robustness of particular properties. Stemming from crystalline symmetries, such topological protection renders the properties robust against defects and provides a platform of rich physics to be studied. Recent developments have revealed the existence of so-called fragile topological phases, where the means of classification due to symmetry is unclear. Z.-D. Song
et al.
and Peri
et al.
present a combined theoretical and experimental approach to identify, classify, and measure the properties of fragile topological phases. By invoking twisted boundary conditions, they are able to describe the properties of fragile topological states and verify the expected experimental signature in an acoustic crystal. Understanding how fragile topology arises could be used to develop new materials with exotic properties.

Science
, this issue p.
794
, p.
797
Psychological, social and contextual factors across recovery stages following a sport-related knee injury: a scoping review
Authors: Truong Linda K , Mosewich Amber D , Holt Christopher J , Le Christina Y , Miciak Maxi , Whittaker Jackie L
Published: February 2020

Objective

To explore the role of psychological, social and contextual factors across the recovery stages (ie, acute, rehabilitation or return to sport (RTS)) following a traumatic time-loss sport-related knee injury.

Material and methods

This review followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Extension for Scoping Reviews and Arksey and O’Malley framework. Six databases were searched using predetermined search terms. Included studies consisted of original data written in English that identified or described a psychological, social or contextual factor related to recovery after a traumatic time-loss sport-related knee injury. Two authors independently conducted title–abstract and full-text reviews. Study quality was assessed using the Mixed Methods Appraisal Tool. Thematic analysis was undertaken.

Results

Of 7289 records, 77 studies representing 5540 participants (37% women, 84% anterior cruciate ligament tears, aged 14–60 years) were included. Psychological factors were investigated across all studies, while social and contextual factors were assessed in 39% and 21% of included studies, respectively. A cross-cutting concept of individualisation was present across four psychological (barriers to progress, active coping, independence and recovery expectations), two social (social support and engagement in care) and two contextual (environmental influences and sport culture) themes. Athletes report multiple barriers to recovery and valued their autonomy, having an active role in their recovery and diverse social support.

Conclusion

Diverse psychological, social and contextual factors are present and influence all stages of recovery following a traumatic sport-related knee injury. A better understanding of these factors at the time of injury and throughout rehabilitation could assist with optimising injury management, promoting RTS, and long-term health-related quality-of-life.
Maintenance motives for physical activity among older adults: a protocol for a systematic review and meta-analysis
Authors: Huffman Mary Katherine , Reed Jason Brian , Carpenter Theresa , Amireault Steve
Published: February 2020

Introduction

Physical activity (PA) is an important aspect for health and well-being, yet many older adults do not maintain their PA long term. The identification of key factors that are associated with, and likely causally related to, older adults’ PA maintenance is a crucial first step towards developing programmes that are effective at promoting long-term PA behaviour change. The purpose of this protocol is to outline a systematic review that will examine the relationship between four motives (ie, satisfaction, enjoyment, self-determination and identity) and older adults’ PA maintenance.

Methods and analysis

Studies that investigated PA maintenance with a sample mean age ≥55 years will be included. Five electronic databases (PubMed, Cumulative Index to Nursing and Allied Health Literature, SPORTDiscus, PsycINFO and ProQuest Dissertations and Theses) were searched on 6 April 2018 with no publication date limit (ie, from inception). One reviewer screened 100% of titles and abstracts (k=21 470) while a random subsample (20%) was screened independently by two reviewers. An update of the search was run on 1 October 2019. All studies for which the full text was retrieved will be independently screened by two reviewers. Data pertaining to study sample, design, motives, PA (eg, measurement validity evidence, study definition of maintenance) and essential bias domains (eg, bias due to missing data) will be extracted. Study-level effect sizes will be calculated, and if the number of studies is ≥5, a random-effects meta-analysis will be performed using inverse-variance methods; a narrative synthesis will be performed otherwise.

Ethics and dissemination

The university’s Human Research Protection Program determined that the proposed study qualifies as exempt from the Institutional Review Board review under Exemption Category 4 (PROPEL #: 80047007). Results will be published in a peer-review journal, and the findings will help inform future interventions with older adults.

PROSPERO registration number

CRD42018088161.
Analysis of the management and costs of headache disorders in Spain during the period 2011–2016: a retrospective multicentre observational study
Authors: Darbà Josep , Marsà Alicia
Published: February 2020

Objectives

To investigate the number and characteristics of the Spanish population affected by headache disorders and the direct medical cost that these patients represent for the healthcare system.

Design

A retrospective multicentre observational study.

Setting

Records from all patients admitted with headache in primary and secondary care centres in Spain between 2011 and 2016 that were registered in a Spanish claims database were included in the analysis. Direct medical costs were calculated using the standardised average expenses of medical procedures determined by the Spanish Ministry of Health.

Results

Data extraction claimed primary care records from 636 722 patients and secondary care records from 30 077 patients. Women represented 63% and 65% of all patients with headache in primary and secondary care respectively, with the exception of cluster headaches, a group with 60% of male patients. No large shifts were observed over time in patients’ profile; contrarily, the number of cases per 10 000 patients attended in primary care increased 2-folds between 2011 and 2016 for migraine and 1.85-folds for other headaches. Migraine was the cause for 28% of primary care consultations and 50% of secondary care admissions, and it was responsible for the largest portion of healthcare costs in 2016, a total amount of € 7 302 718. The estimated annual direct medical cost of headache disorders was € 10 716 086.

Conclusions

Migraine was responsible for half of the secondary care admissions linked to headache disorders. The raise detected in the number of cases registered in primary care is likely to impact the direct medical costs associated to these disorders causing an increase in the total burden they represent for the Spanish National Healthcare System.
Study protocol for a multisite randomised controlled trial of a rehabilitation intervention to reduce participation restrictions among female breast cancer survivors
Authors: Stevens Courtney J , Hegel Mark T , Bakitas Marie Anne , Bruce Martha , Azuero Andres , Pisu Maria , Chamberlin Mary , Keene Kimberly , Rocque Gabrielle , Ellis Daphne , Gilbert Tiffany , Morency Jamme L , Newman Robin M , Codini Megan E , Thorp Karen E , dos Anjos Sarah M , Cloyd Danielle Z , Echols Jennifer , Milford Ashley N , Ingram Stacey A , Davis Jasmine , Lyons Kathleen Doyle
Published: February 2020

Introduction

Many breast cancer survivors report an inability to fully participate in activities of daily living after completing cancer treatment. Reduced activity participation is linked to negative consequences for individuals (eg, depression, reduced quality of life) and society (reduced workforce participation). There is currently a lack of evidence-based interventions that directly foster cancer survivors’ optimal participation in life roles and activities. Pilot study data suggest rehabilitation interventions based on behavioural activation (BA) and problem-solving treatment (PST) can facilitate post-treatment role resumption among breast cancer survivors.

Methods and analysis

This protocol describes a multisite randomised controlled trial comparing a 4-month long, nine-session BA and PST-informed rehabilitation intervention (BA/PS) against a time-matched, attention control condition. The overall objective is to assess the efficacy of BA/PS for enhancing breast cancer survivors’ activity participation and quality of life over time. A total of 300 breast cancer survivors reporting participation restrictions after completing curative treatment for stage 1–3 breast cancer within the past year will be recruited across two sites (Dartmouth-Hitchcock Medical Center and University of Alabama at Birmingham). Assessments are collected on enrolment (T1) and 8 (T2), 20 (T3) and 44 (T4) weeks later.

Ethics and dissemination

Study procedures are approved by the Committee for the Protection of Human Subjects at Dartmouth College, acting as the single Institutional Review Board of record for both study sites (STUDY 00031380). Results of the study will be presented at national meetings and submitted for publication in peer-reviewed journals.

Trial registration number

NCT03915548; Pre-results.
Laboratory-based Intermountain Validated Exacerbation (LIVE) Score stability in patients with chronic obstructive pulmonary disease
Authors: Blagev Denitza P , Collingridge Dave S , Rea Susan , Carey Kyle A , Mularski Richard A , Zeng Siyang , Arjomandi Mehrdad , Press Valerie G
Published: February 2020

Background

The Laboratory-based Intermountain Validated Exacerbation (LIVE) Score is associated with mortality and chronic obstructive pulmonary disease (COPD) exacerbation risk across multiple health systems. However, whether the LIVE Score and its associated risk is a stable patient characteristic is unknown.

Methods

We validated the LIVE Score in a fourth health system. Then we determined the LIVE Score stability in a retrospective cohort of 98 766 patients with COPD in four health systems where it was previously validated. We assessed whether LIVE Scores changed or remained the same over time. Stability was defined as a majority of surviving patients having the same LIVE Score 4 years later.

Results

The LIVE Score separated patients into three LIVE Score risk groups of low, medium, and high mortality and LIVE Score stability. Mortality ranged from 6.2% for low-risk LIVE to 45.8% for high-risk LIVE (p<0.001). We found that low-risk LIVE groups were stable and high-risk LIVE groups were unstable. Low-risk LIVE group patients remained low risk, but few high-risk LIVE group patients remained high risk (79.0% high vs 48.1% medium vs 8.8% low, p<0.001 for all pairwise comparisons).

Conclusion

The LIVE Score identifies three major clinically actionable cohorts: a stable low-risk LIVE group, an unstable high-risk LIVE group with high mortality rates, and a medium-risk LIVE group. These observations further our understanding of how existing data used to calculate the LIVE Score may target interventions across risk cohorts of patients with COPD in a health system.
Assessment of home hazards for non-fatal childhood injuries in rural Nepal: a community survey
Authors: Bhatta Santosh , Mytton Julie A , Deave Toity
Published: February 2020

Background

Unintentional injuries in and around the home are important causes of preventable death and disability among young children globally. In Nepal, there is a lack of data regarding home injuries and home hazards to guide the development of effective interventions for preventing childhood home injuries. This study aimed to determine the burden of unintentional home injuries in children <5 years in rural Nepal and quantify the injury hazards in their homes.

Methods

A survey was conducted in 740 households in rural areas of the Makwanpur district during February and March 2015. The primary carer reported home injuries which occurred in the previous 3 months and data collector observation identified the injury hazards. Injury incidence, mechanism and the proportion of households with different hazards were described. Multivariable logistic regression explored associations between the number and type of home hazards and injuries.

Results

Injuries severe enough to need treatment, or resulting in non-participation in usual activities for at least a day, were reported in 242/1042 (23.2%) children <5 years. The mean number of injury hazards per household was 14.98 (SD=4.48), range of 3–31. Regression analysis found an estimated increase of 31% in the odds of injury occurrence associated with each additional injury hazard found in the home (adjusted OR 1.31; 95% CI 1.20 to 1.42).

Conclusions

A high proportion of young children in rural Nepal sustained injuries severe enough to miss a day of usual activities. Increased frequency of hazards was associated with an increased injury risk.
MiR-21, EGFR and PTEN in non-small cell lung cancer: an in situ hybridisation and immunohistochemistry study
Authors: Marin Irina , Ofek Efrat , Bar Jair , Prisant Nadia , Perelman Marina , Avivi Camila , Lavy-Shahaf Gitit , Onn Amir , Katz Ruth , Barshack Iris
Published: February 2020

Aims

To analyse microRNA (miR)-21 distribution and expression at the cellular level in non-small cell lung cancer (NSCLC). MiR-21 is an oncogenic microRNA overexpressed in NSCLC. In previous studies, overexpression of miR-21 was evaluated from the tumour bulk by quantitative reverse transcription PCR with results expressed on average across the entire cell population.

Methods

We used in situ hybridisation and immunohistochemistry to assess the correlation between miR-21 levels and the expression of markers that may be possible targets (epidermal growth factor reaction) or may be involved in its upregulation (phosphatase and tensin homolog (PTEN), p53). The Pearson’s χ2tests was used to assess correlation with clinicopathological data and with miR-21 expression both in tumour and tumour stroma.

Results

Cytoplasmic staining and expression of Mir-21 were detected in the tumours and in associated stromal cells. Expression was highest in the stroma immediately surrounding the tumour cells and decreased as the distance from the tumour increased. No expression of miR-21 was found in normal lung parenchyma and a significant association was found between tumour localised miR-21 and PTEN.

Conclusions

Presence of miR-21 in both cell tumour and stromal compartments of NSCLC and the relationship with PTEN confirms miR-21 as a microenvironment signalling molecule, possibly inducing epithelial mesenchymal transition and invasion by targeting PTEN in the stromal compartment possibly through exosomal transport. In situ immunohistochemical studies such as ours may help shed light on the complex interactions between miRNAs and its role in NSCLC biology.
Public attention for private concerns: intellectual disability parents’ organisations in the Republic of Ireland, 1955–1970
Authors: Kilgannon David
Published: February 2020

This article examines the influence of intellectual disability ‘parents and friends’ organisations in the Republic of Ireland between 1955 and 1970, a period that coincided with the emergence of parental disability activism internationally. Drawing on their publications and activities, it argues that Irish groups adopted a significant, if circumscribed, response to ‘learning disabilities’ that was reflective of a broader political and social policy approach during the midcentury, with local organisations supporting parents of ‘deficient’ children and establishing key services across the country. It highlights the way in which these pioneering actions align with existing norms in the state and explores the effect of this voluntary-driven response for the intellectually disabled. Approached in this way, the actions of these learning disability organisations complicate international research on postwar disability activism while furthering an emergent body of research into the complex realities that precluded transformative change in Irish society during the mid-20th century.
Role of flavours in vaping uptake and cessation among New Zealand smokers and non-smokers: a cross-sectional study
Authors: Gendall Philip , Hoek Janet
Published: February 2020

Background

Concerns about the effects of vaping have prompted calls to restrict e-cigarette flavours. Vaping proponents have criticised these proposals, which they argue may discourage smokers from taking up vaping or trigger relapse to smoking. We explored the role flavours play in vaping uptake and cessation among New Zealand cigarette smokers and vaping-susceptible never smokers (VSNS), and examined current vapers’ preferred flavours.

Methods

We conducted an online survey of 1005 New Zealanders aged 18–70 years that included 324 current vapers (vaped in the last 30 days) and 302 ‘past’ vapers (reported past vaping, but not within the last month). We asked respondents their reasons for vaping and explored current vapers’ preferred e-cigarette flavours; we analysed the data using descriptive statistics and logistic regression.

Results

Irrespective of smoking status, flavour was one of the main reasons respondents gave for vaping (smokers 83%; former smokers 77%; VSNS 80%). Flavour was less important to former vapers; 47% of smokers, 57% of former smokers and 64% of VSNS cited flavour as a reason for originally taking up vaping. Fruit flavours were most popular among all three groups; smokers also favoured tobacco flavour, while former smokers also favoured mint or menthol, and never smokers also favoured confectionery/sweets/lolly flavours.

Conclusions

Flavours play a major role in vaping initiation for current smokers, former smokers and vaping-susceptible non-smokers, and remain important to those who continue vaping. Our findings highlight the need for regulation that allows some flavour diversity without the extravagant marketing currently used to promote vaping and e-liquids.
Life under an oil slick: response of a freshwater food web to simulated spills of diluted bitumen in field mesocosms
Authors: Cederwall Jeffrey , Black Tyler A. , Blais Jules M. , Hanson Mark L. , Hollebone Bruce P. , Palace Vince P. , Rodríguez-Gil José Luis , Greer Charles W. , Maynard Christine , Ortmann Alice C. , Rooney Rebecca C. , Orihel Diane M.
Published: February 2020

Heavy crude oil transportation over land is increasing, yet the ecological impacts of spills, particularly of diluted bitumen, in freshwater environments remain poorly understood. We simulated spills of diluted bitumen in 1400 L land-based mesocosms containing water and sediments from a boreal, oligotrophic lake and monitored the response of natural planktonic communities over 11 days. Most species of phytoplankton (chrysophytes and dinoflagellates) and zooplankton (copepods and cladocerans) were sensitive to oil, exhibiting >70% overall abundance reductions in response to the spills. Declines in nano- and microphytoplankton were short-lived and began to recover after the oil sank, whereas picophytoplankton and zooplankton populations remained depressed at the end of the experiment. In contrast, oil spills stimulated bacteria known to degrade hydrocarbons, especially Alphaproteobacteria, whereas Gammaprotobacteria (a common marine oil spill bacterial class) increased less. This is the first experiment to examine the effects of diluted bitumen in a multitrophic freshwater community.
Fat brane, dark matter and localized kinetic terms in six dimensions
Authors: Landim Ricardo G.
Published: February 2020

Extra dimensions (ED) have been used as attempts to explain several phenomena in particle physics over the years. In this paper we investigate the role of an abelian gauge field as mediator of the interaction between dark matter (DM) and Standard Model (SM) particles, in a model with two flat and transverse ED compactified on the chiral square. DM is confined in a thin brane, localized at the origin of the chiral square, while the SM is localized in a finite width brane, lying in the opposite corner of the square. A brane-localized kinetic term is present in the DM brane, while in the fat brane it is not allowed. In this model the kinetic mixing is not required because we assume that the SM particles couple to the mediator through their $$B-L$$B-L charges, while DM couples to it via a dark charge. Assuming a complex scalar field as DM candidate it is possible to obtain the observed DM relic abundance and avoid direct detection constraints for some parameter choices.
Current correlation functions from a bosonized theory in $$3/2+1$$ dimensions
Authors: Fosco C. D. , Schaposnik F. A.
Published: February 2020

Within the context of a bosonized theory, we evaluate the current-current correlation functions corresponding to a massive Dirac field in $$2+1$$2+1 dimensions, which is constrained to a spatial half-plane. The boundary conditions are imposed on the dual theory, and have the form of of perfect-conductor conditions. We also consider, for the sake of comparison, the purely fermionic version of the model and its boundary conditions, in the large-mass limit. We apply the result about the dual theory to the evaluation of induced vacuum currents in the presence of an external field, in a spatial half-plane.
Microfluidic sensor applications by using chiral metamaterial
Authors: Dalgac Sekip , Bakır Mehmet , Karadag Faruk , Karaaslan Muharrem , Akgol Oguzhan , Unal Emin , Sabah Cumali
Published: February 2020

Chiral metamaterial-based sensor is designed for sensing the change in substance ratio of chemical substances when combined with distilled water. These samples have been prepared with 10%, 50% and 90% volume fraction of methanol, ethanol, acetone, ammonia and isopropyl alcohol. The complex permittivity of the prepared samples has been measured by Agilent 85070E dielectric probe kit and compared with the simulations. In the proposed design, linear shifts with the frequency bands of more than 100 MHz are observed in different measurements. For different material sensing, pure samples have been used and their reflection coefficient measurement results have been presented. Unique side of this study is that the structure provides very clear and sensitive results and presents a new approach to the microfluidic sensor applications by using the sample holder.
On the Structure of Positive Solutions for the Shigesada–Kawasaki–Teramoto Model with Large Interspecific Competition Rate
Authors: Kan-on Yukio
Published: February 2020

In this paper, we treat the competition-diffusion system with nonlinear diffusion term, which was proposed by Shigesada et al. [1979], and discuss the bifurcation structure of positive solution for the system when the interspecific competition rate is sufficiently large. To do this, we derive two kinds of limiting systems as the interspecific competition rate tends to infinity, and study the bifurcation structure of positive solution for each limiting system by employing the comparison principle and the bifurcation theory.
Slow-Scale and Fast-Scale Instabilities in Parallel-Connected Single-Phase H-Bridge Inverters: A Design-Oriented Study
Authors: Yang Lihui , Yang Lan , Yang Fang , Ma Xikui
Published: February 2020

This paper reports the slow- and fast-scale instabilities in the parallel-connected single-phase H-bridge inverters and discusses the two types of instabilities from the practical design viewpoint. Simulations show that the slow-scale instability which occurs in the whole line cycle is a type of global instability, whereas the fast-scale instability which occurs around the middle time of each half-line cycle is a type of local instability. In order to reveal the mechanisms of the slow- and fast-scale instabilities, theoretical analyses are carried out through the derived averaged model and discrete-time model, respectively. It is identified that the slow-scale instability is due to the occurrence of Hopf bifurcation, and the fast-scale instability manifests itself as period-doubling bifurcation. Furthermore, stability boundaries in various design parameter spaces considering the mismatches in different system parameters between inverter modules, as well as the effects of the current-sharing control loop on the slow- and fast-scale instabilities are also given. Besides, the influences of the nonlinear load and the control method for parallel system on the two types of instabilities are briefly discussed. These findings can be used to guide the tuning of the paralleled inverter system parameters to ensure stable operation in practice. Finally, experimental results are presented to verify the results of the simulation and theoretical analysis.
Global Phase Portraits of ℤ2-Symmetric Planar Polynomial Hamiltonian Systems of Degree Three with a Nilpotent Saddle at the Origin
Authors: Corbera Montserrat , Valls Claudia
Published: February 2020

We characterize the phase portraits in the Poincaré disk of all planar polynomial Hamiltonian systems of degree three with a nilpotent saddle at the origin and [Formula: see text]-symmetric with [Formula: see text].
Investigations on the Structural, Optical and Dielectric Properties of Ball-Milled ZnO–Fe2O3 Nanocomposites
Authors: Balachandar V. , Brijitta J. , Viswanathan K. , Sampathkumar R.
Published: February 2020

In this study, ZnO–Fe2O3 nanocomposites were prepared by high-energy ball milling technique and characterized through X-ray diffraction (XRD), field-emission scanning electron microscopy (FESEM), UV–visible spectroscopy and dielectric spectroscopy. The amount of Fe2O3 in the ZnO–Fe2O3 nanocomposites was varied at the rates of 1[Formula: see text]wt.%, 3[Formula: see text]wt.% and 5[Formula: see text]wt.% in order to investigate its influence on the structural, optical and dielectric properties of the nanocomposites. XRD patterns of nanocomposites revealed no shift in peak positions and hence confirmed the formation of composites after ball milling. Further, it was observed from FESEM analysis that Fe2O3 particles were distributed randomly on the ZnO matrix of the nanocomposites. ZnO–Fe2O3 nanocomposites reveal extended optical absorption in the range of 400–600[Formula: see text]nm from UV studies. The dielectric constant and loss of the nanocomposites decrease exponentially with increase in frequency. The composition and frequency dependences of the dielectric constant, dielectric loss and AC conductivity are explained based on the Maxwell–Wagner effect and Koop’s theory.
Computational Speeds of Three Parabolic Approximations
Authors: Spiesberger John L. , Mikhin Dmitry Yu.
Published: February 2020

Computational speeds are compared for modern implementations of three parabolic equation approximations. The split-step c0-insensitive model is 3.7 and 5.5 times faster than the finite-difference model OWWE and finite-element model RAM, respectively. Calculations are made between a source and receiver separated horizontally by 1000[Formula: see text]km at 600[Formula: see text]m depth near the minimum of sound speed in the deep ocean. Sound speed varies with depth but not range. The impulse response is computed by applying an inverse Fourier transform to equispaced discrete frequencies between 50[Formula: see text]Hz and 100[Formula: see text]Hz. At convergence, all implementations yield multipath travel times and transmission losses within 7[Formula: see text]ms and 2.4[Formula: see text]dB of an exact solution computed with normal modes via KRAKEN.
Alteration of cardiolipin biosynthesis and remodeling in single right ventricle congenital heart disease
Authors: Garcia Anastacia M. , McPhaul Jessica C. , Sparagna Genevieve C. , Jeffrey Danielle A. , Jonscher Raleigh , Patel Sonali S. , Sucharov Carmen C. , Stauffer Brian L. , Miyamoto Shelley D. , Chatfield Kathryn C.
Published: February 2020

Despite advances in both medical and surgical therapies, individuals with single ventricle heart disease (SV) remain at high risk for the development of heart failure (HF). However, the molecular mechanisms underlying remodeling and eventual HF in patients with SV are poorly characterized. Cardiolipin (CL), an inner mitochondrial membrane phospholipid, is critical for proper mitochondrial function, and abnormalities in CL content and composition are known in various cardiovascular disease etiologies. The purpose of this study was to investigate myocardial CL content and composition in failing and nonfailing single right ventricle (RV) samples compared with normal control RV samples, to assess mRNA expression of CL biosynthetic and remodeling enzymes, and to quantitate relative mitochondrial copy number. A cross-sectional analysis of RV myocardial tissue from 22 failing SV (SVHF), 9 nonfailing SV (SVNF), and 10 biventricular control samples (BVNF) was performed. Expression of enzymes involved in CL biosynthesis and remodeling were analyzed using RT-qPCR and relative mitochondrial DNA copy number determined by qPCR. Normal phase high-pressure liquid chromatography coupled to electrospray ionization mass spectrometry was used to quantitate total and specific CL species. While mitochondrial copy number was not significantly different between groups, total CL content was significantly lower in SVHF myocardium compared with BVNF controls. Despite having lower total CL content however, the relative percentage of the major tetralinoleoyl CL species is preserved in SVHF samples relative to BVNF controls. Correspondingly, expression of enzymes involved in CL biosynthesis and remodeling were upregulated in SVHF samples when compared with both SVNF samples and BVNF controls.

NEW & NOTEWORTHY The mechanisms underlying heart failure in the single ventricle (SV) congenital heart disease population are largely unknown. In this study we identify alterations in cardiac cardiolipin metabolism, composition, and content in children with SV heart disease. These findings suggest that cardiolipin could be a novel therapeutic target in this unique population of patients.
Reconstruction of a lncRNA-Associated ceRNA Network in Endothelial Cells under Circumferential Stress
Authors: Huang Zhuhui , Winata William Adiwignya , Zhang Kui , Zhao Yang , Li Yang , Zhou Ning , Zhou Shaoyou , Fu Wei , Qiao Bokang , Li Guoqi , Shao Yihui , Zheng Jubing , Dong Ran
Published: February 2020

Background. Numerous studies have highlighted that long noncoding RNA (lncRNA) can indirectly regulate the expression of mRNAs by binding to microRNA (miRNA). LncRNA-associated ceRNA networks play a vital role in the initiation and progression of several pathological mechanisms. However, the lncRNA-miRNA-mRNA ceRNA network in endothelial cells under cyclic stretch is seldom studied. Methods. The miRNA, mRNA, and lncRNA expression profiles of 6 human umbilical vein endothelial cells (HUVECs) under circumferential stress were obtained by next-generation sequencing (NGS). We identified the differential expression of miRNAs, mRNAs, and lncRNAs using the R software package GDCRNATools. Cytoscape was adopted to construct a lncRNA-miRNA-mRNA ceRNA network. In addition, through GO and KEGG pathway annotations, we analyzed gene functions and their related pathways. We also adopted ELISA and TUNEL to investigate the effect of si-NEAT1 on endothelial inflammation and apoptosis. Results. We recognized a total of 32978 lncRNAs, 1046 miRNAs, and 31958 mRNAs in 6 samples; among them, 155 different expressed lncRNAs, 74 different expressed miRNAs, and 960 different mRNAs were adopted. Based on the established theory, the ceRNA network was composed of 13 lncRNAs, 44 miRNAs, and 115 mRNAs. We constructed and visualized a lncRNA-miRNA-mRNA network, and the top 20 nodes are identified after calculating their degrees. The nodes with most degrees in three kinds of RNAs are hsa-miR-4739, NEAT1, and MAP3K2. Functional analysis showed that different biological processes enriched in biological regulation, response to stimulus and cell communication. Pathway analysis was mainly enriched in longevity regulating, cell cycle, mTOR, and FoxO signaling pathway. Circumferential stress can significantly downregulate NEAT1, and after transducing si-NEAT1 for 24 h, inflammatory cytokine IL-6 and MCP-1 were significantly increased; furthermore, fewer TUNEL-positive cells were found in the si-NEAT1 treated group. Conclusions. The establishing of a ceRNA network can help further understand the mechanism of vein graft failure. Our data demonstrated that NEAT1 may be a core factor among the mechanical stress factors and that cyclic stress can significantly reduce expression of NEAT1, give rise to inflammation in the early stage of endothelial dysfunction, and promote EC apoptosis, which may play an essential role in vein graft failure.
A Collaborative Deep and Shallow Semisupervised Learning Framework for Mobile App Classification
Authors: Lv MingQi , Huang Chao , Chen TieMing , Wang Ting
Published: February 2020

With the rapid growth of mobile Apps, it is necessary to classify the mobile Apps into predefined categories. However, there are two problems that make this task challenging. First, the name of a mobile App is usually short and ambiguous to reflect its real semantic meaning. Second, it is usually difficult to collect adequate labeled samples to train a good classifier when a customized taxonomy of mobile Apps is required. For the first problem, we leverage Web knowledge to enrich the textual information of mobile Apps. For the second problem, the mostly utilized approach is the semisupervised learning, which exploits unlabeled samples in a cotraining scheme. However, how to enhance the diversity between base learners to maximize the power of the cotraining scheme is still an open problem. Aiming at this problem, we exploit totally different machine learning paradigms (i.e., shallow learning and deep learning) to ensure a greater degree of diversity. To this end, this paper proposes Co-DSL, a collaborative deep and shallow semisupervised learning framework, for mobile App classification using only a few labeled samples and a large number of unlabeled samples. The experiment results demonstrate the effectiveness of Co-DSL, which could achieve over 85% classification accuracy by using only two labeled samples from each mobile App category.
3D Simulation Analysis of Central Shunt in Patient-Specific Hemodynamics: Effects of Varying Degree of Pulmonary Artery Stenosis and Shunt Diameters
Authors: Liu Jiawei , Yuan Haiyun , Zhang Neichuan , Chen Xiangyu , Zhou Chengbin , Huang Meiping , Jian Qifei , Zhuang Jian
Published: February 2020

The objective of this study was to compare the effects of different shunt diameters and pulmonary artery (PA) stenosis grades on the hemodynamics of central shunts to determine an optimal surgical plan and improve the long-term outcomes of the operation. A 3D anatomical model was reconstructed based on the patient’s clinical CT data. 3D computational fluid dynamics models were built with varying degrees of stenosis (the stenosis ratio α was represented by the ratio of blood flow through the main pulmonary artery to cardiac output, ranging from 0 to 30%; the smaller the value of α, the more severe the pulmonary artery stenosis) and varying shunt diameters (3, 3.5, 4, 4.5, and 5 mm). Our results show that the asymmetry of pulmonary artery flow increased with increasing shunt diameter and α, which will be more conducive to the development of the left pulmonary artery. Additionally, the pulmonary-to-systemic flow ratio (QP/QS) increases with the shunt diameter and α, and all the values exceed 1. When the shunt diameter is 3 mm and α = 0%, QP/QS reaches the minimum value of 1.01, and the oxygen delivery reaches the maximum value of 205.19 ml/min. However, increasing shunt diameter and α is beneficial to reduced power loss and smoother PA flow. In short, for patients with severe PA stenosis (α is small), a larger-diameter shunt may be preferred. Conversely, when the degree of PA stenosis is moderate, a smaller shunt diameter can be considered.
AXL as a Target in Breast Cancer Therapy
Authors: Colavito Sierra A.
Published: February 2020

AXL is a receptor tyrosine kinase (RTK) that has been implicated in diverse tumor-promoting processes such as proliferation, migration, invasion, survival, and apoptosis. AXL therefore plays a role in cancer progression, and AXL has been implicated in a wide variety of malignancies from solid tumors to hematopoietic cancers where it is often associated with poor prognosis. In cancer, AXL has been shown to promote epithelial to mesenchymal transition (EMT), metastasis formation, drug resistance, and a role for AXL in modulation of the tumor microenvironment and immune response has been identified. In light of these activities multiple AXL inhibitors have been developed, and several of these have entered clinical trials in the U.S. In breast cancer, high levels of AXL expression have been observed. The role of AXL in cancer with a focus on therapeutic implications for breast cancer is discussed.
Locally Delivered Umbilical Cord Mesenchymal Stromal Cells Reduce Chronic Inflammation in Long-Term Nonhealing Wounds: A Randomized Study
Authors: Suzdaltseva Yulia , Zhidkih Sergey , Kiselev Sergey L. , Stupin Victor
Published: February 2020

Inflammation is part of a complex biological response to injury that mediates a rapid mobilization of cells and triggers the restoration of tissue homeostasis. The systemic diseases of the connective tissues, repetitive strain injuries, neuropathy, and vascular impairment lead to the development of a chronic inflammatory state. In such cases, a forced intervention is required to trigger tissue regeneration. Mesenchymal stromal cells (MSCs) have been considered a perspective tool for regenerative medicine because of their ability to change the expression and secretory profile under the influence of signals from the microenvironment to perform a regulatory function at the site of tissue damage. In this study, MSCs were isolated from the human umbilical cord (UCMSCs). The ability of UCMSCs to regulate chronic inflammation was investigated in a randomized placebo-controlled pilot study to assess the efficacy and safety of UCMSC therapy in patients with nonhealing wounds. A total of 108 patients with chronic wounds of different etiologies were randomly divided into two groups according to the criteria of inclusion and exclusion. The group (n=59) that was treated with a single local subcutaneous infusion of UCMSCs around the wound periphery showed a pronounced growth of granulation tissue, improved blood microcirculation, and reduction in wound size compared to the placebo group (n=49). No prominent adverse events were detected in patients from the UCMSC group during the 1-year follow-up period. This research has demonstrated that locally delivered allogeneic UCMSCs can contribute to chronic wound repair and provide an additional support toward new therapeutic strategies. Registration certificate №FS2006/341 was issued by the Federal Service for Surveillance in Healthcare.
Can the Executive Control Network be Used to Diagnose Parkinson’s Disease and as an Efficacy Indicator of Deep Brain Stimulation?
Authors: Dong Wenwen , Qiu Chang , Jiang Xu , Shen Bo , Zhang Li , Liu Weiguo , Zhang Wenbin , Chen Jiu
Published: February 2020

Objective. The aim of this work was to investigate whether there are differences in the executive control network (ECN) between patients with Parkinson’s disease (PD) before and after deep brain stimulation (DBS) surgery and to explore how deep brain stimulation (DBS) surgery affects ECN connectivity in patients with PD. Methods. Resting-state magnetic resonance imaging (MRI) data were obtained from 23 patients with Parkinson’s disease preoperatively (pre-PD) and postoperatively (post-PD) and 14 normal controls (CN). The right dorsolateral prefrontal cortex (DLPFC) was used as the seed region of interest (ROI) to study the characteristics of the functional connectivity of the ECN in these subjects. Results. There were differences in the ECN among PD patients before and after surgery and between the CN. Compared with the CN group, the pre-PD patients showed significantly reduced functional connectivity (FC) between the DLPFC and the left inferior frontal gyrus, left precuneus, left cerebellum posterior lobe, right middle frontal gyrus, right inferior parietal gyrus, right posterior central gyrus, right precuneus, and right inferior frontal gyrus. Compared to the CN group, the post-PD patients showed significantly reduced FC between the DLPFC and left inferior frontal gyrus, left precuneus, left cerebellum posterior lobe, right middle frontal gyrus, right inferior frontal gyrus, and right parietal lobule. There is no difference in the ECN between the pre-PD patients and the post-PD patients. Conclusions. The FC of ECN in PD patients was different from that in normal controls, but the FC of the ECN in patients with PD may not be altered by DBS. This suggests that the ECN may be considered an imaging biomarker for the identification of PD but may not be a good imaging biomarker for the evaluation of DBS efficacy.
Analysis of Association of Occupational Physical Activity, Leisure-Time Physical Activity, and Sedentary Lifestyle with Hypertension according to the Adherence with Aerobic Activity in Women Using Korea National Health and Nutrition Examination Survey 2016-2017 Data
Authors: Ryu Mikyung , Lee Sol , Gym Ho , Baek Weon-Chil , Kimm Heejin
Published: February 2020

Purpose. We investigated the association between occupational physical activity, leisure-time physical activity, and sedentary lifestyle with hypertension by adherence with aerobic exercise in middle-aged and elderly women.Methods. A cross-sectional analysis was performed using Korea National Health and Nutrition Examination Survey (KNHANES), a nationally representative data between 2016 and 2017. A total of 4,241 women aged 40 years or older were included. Hypertension diagnosed by physician and exercise status was asked by questionnaires.Results. Mean age of the participants was 58.4 (±11.4, range: 40∼80 years). There were 1,681 (39.6%) women in the aerobic activity adherence group. In the logistic regression analysis with adjustment for confounding factors, frequency of occupational physical activity (OPA) level (OR 1.931;p=0.048, in ≤4 per week group), walking frequency (OR 0.436;p=0.001, in 5∼7 days per week walking group compared with never walking group) in the aerobic activity adherence group, sitting hours (OR 1.849; 95% CI: 1.279–2.673,p=0.001, in 13 hours or longer group compared with 6 hours or less sitting hours group), and muscle strengthening exercises (OR 0.554; 95% CI: 0.353–0.870,p=0.010, 1∼4 days per week compared with never) in the nonadherence group were significantly associated with hypertension.Conclusions. In the aerobic activity adherence group, further research is needed to identify the influence of occupational physical activity. In the aerobic activity nonadherence group, decreasing sitting hours and increasing endurance exercise may be helpful.