bluuebunny/crossref_metadata_2025 huggingface dataset:
Normobaric hypoxia does not alter the critical environmental limits for thermal balance during exercise‐heat stress
Authors: Coombs Geoff B. , Cramer Matthew N. , Ravanelli Nicholas , Imbeault Pascal , Jay Ollie
Published: March 2020

New Findings

What is the central question of this study?

Hypoxia reportedly does not impair thermoregulation during exercise in compensable heat stress conditions: does it have an impact on maximal heat dissipation and therefore the critical environmental limit for the physiological compensability of core temperature?

What is the main finding and its importance?

Although skin blood flow was higher in hypoxia, no differences in sweat rates or the critical environmental limit for the physiological compensability of core temperature – an indicator of maximal heat loss – were found compared to exercise in normoxia, indicating no influence of normobaric hypoxia on thermoregulatory capacity in warm conditions.

Altered control of skin blood flow (SkBF) in hypoxia does not impair thermoregulation during exercise in compensable conditions, but its impact on maximal heat dissipation is unknown. This study therefore sought to determine whether maximum heat loss is altered by hypoxia during exercise in warm conditions. On separate days, eight males exercised for 90 min at a fixed heat production of ∼500 W in normoxia (NORM) or normobaric hypoxia (HYP,  = 0.13) in a 34°C environment. Ambient vapour pressure was maintained at 2.13 kPa for 45 min, after which it was raised 0.11 kPa every 7.5 min. The critical ambient vapour pressure at which oesophageal temperature inflected upward (Pcrit) indicated that maximum heat dissipation had been reached. Neither local sweat rates on the upper arm, back and forehead (average NORM: 1.46 (0.15) vs. HYP: 1.41 (0.16) mg cm−2 min−1; P = 0.59) nor whole‐body sweat losses (NORM: 1029 (137) g vs. HYP: 1025 (150) g; P = 0.95) were different between trials. Laser‐Doppler flux values (LDF; arbitrary units), an index of SkBF, were not different between NORM and HYP on the forearm (P = 0.23) or back (P = 0.73); however, when normalized as a percentage of maximum, LDF values tended to be higher in HYP compared to NORM at the forearm (condition effect, P = 0.05) but not back (P = 0.19). Despite potentially greater SkBF in hypoxia, there was no difference in Pcrit between conditions (NORM: 3.67 (0.35) kPa; HYP: 3.46 (0.39) kPa; P = 0.22). These findings suggest that hypoxia does not independently alter thermoregulatory capacity during exercise in warm conditions.
The Effect of Inlet Swirl on Brush Seal Bristle Deflections and Stability
Authors: Liu Yuxin , Chew John W. , Pekris Michael J. , Kong Xiaozhi
Published: March 2020

This paper considers three-dimensional (3D) computational fluid dynamics (CFD) and structural modeling of brush seals, and investigates the effects of inlet swirl on the bristle pack. The model couples aerodynamic forces generated by CFD to a structural model that includes interaction between bristles. At a critical value of inlet swirl, aerodynamic forces cause circumferential slip of the upstream bristle row. In practice, this may lead to instability of the bristle pack and is consistent with anecdotal reports of seal behavior. The critical swirl velocity was reduced when the downstream pressure level was raised, keeping the same upstream total to downstream static pressure difference. This is caused by the increased dynamic head associated with the inlet swirl. Inclusion of a front plate in the seal design does not offer the intended protection to the bristle pack in highly swirling environments. This is associated with highly swirling flow impinging on the bristle tips. Fitting of roughness elements on the upstream face of the front plate could improve stability by reducing swirl of the flow impacting on the bristles. Increasing the bristle diameter and bristle stiffness does not necessarily prevent slip at higher inlet swirl velocities, but reduces the magnitude of slip of the upstream bristles.
An Accurate Linearization of Electromagnetic Force of Heteropolar Magnetic Bearings With Redundant Structures
Authors: Xin Cheng , Baixin Cheng , Han Liu , G. M Allen
Published: March 2020

Fault tolerance is one of the practical and effective approaches to improve the reliability of magnetic bearings. The linearization of the electromagnetic force (EMF) from the redundant structures is the crucial basis of the design of a fault-tolerant controller. In this paper, we propose an accurate linearization approach for the heteropolar magnetic bearings with redundant structures by solving the Taylor series expansion equation of the current distribution matrix (W) in the nonequilibrium position and introducing a set of displacement compensation matrices to establish a unified accurate EMF model including the controlled current and rotor position. The proposed approach can effectively decrease the EMF error between the actual physical model and the linearized model compared with the existing methods for the consideration of the rotor position. Moreover, the solutions of the current distribution matrix and the relevant optimization approach have been presented on the basis of the proposed approach to help to design a high-performance fault-tolerant controller in the entire rotor displacement range. The numerical results demonstrated the noticeable accuracy advantages of the proposed EMF model.
Single photon beat note in an acousto-optic modulator-based interferometer
Authors: Mathevet Renaud , Chalopin Benoit , Massenot Sébastien
Published: March 2020

We present in the following a quantum optics experiment appropriate for advanced undergraduate students with former experience in quantum optics. It extends classical single photon setups to the time dependent domain. We demonstrate self-heterodyning of heralded single photons using a Mach-Zehnder like interferometer where beamsplitters are replaced by two acousto-optic modulators (AOMs). The single photon beat note is recorded over time at the frequency difference between the RF generators driving the AOMs, which makes it observable directly on a human time scale, i.e., with periods above a fraction of a second. To compare with our observations, we tailor the standard quantum optics formalism for beam splitters to take into account the frequency shifts associated with the AOMs.
The Persian Immortals: A classical case of self-organization
Authors: Kanellopoulos Giorgos , Razis Dimitrios , van der Weele Ko
Published: March 2020

We present an example from classical history that perfectly illustrates the concept of a self-organizing system, namely, the “Persian Immortals” described by Herodotus. Their name refers to the fact that their number was always kept constant (at 10 000) by instantly substituting every warrior who fell during a battle. One evident advantage of this was to undermine the morale of the enemy troops. Here, we focus on a second major benefit, namely, that the Immortals—thanks to the replacement tactics—were actually becoming a stronger unit in the course of the battle. Modeling the substitution of the fallen ones by a plausible set of replacement rules, and using Order Statistics to analyze the evolution of the unit's fitness, we show that the distribution of fighting skills will ripen to a robust and favorable equilibrium state.
Coronavirus disruptions reverberate through research
Authors: Servick Kelly , Cho Adrian , Couzin-Frankel Jennifer , Guglielmi Giorgia
Published: March 2020

Scientists grapple with halted projects and locked-down labs.
The lost colony
Authors: Kintisch Eli
Published: March 2020

Some 900,000 king penguins vanished without a trace. Why?
Golgi-derived PI
(
4
)
P-containing vesicles drive late steps of mitochondrial division
Authors: Nagashima Shun , Tábara Luis-Carlos , Tilokani Lisa , Paupe Vincent , Anand Hanish , Pogson Joe H. , Zunino Rodolfo , McBride Heidi M. , Prudent Julien
Published: March 2020

PI(4)P regulates mitochondrial fission

Mitochondria are dynamic intracellular organelles, the shape and number of which are regulated by various cell-signaling pathways. Mitochondrial division is driven by the recruitment of a constricting guanosine triphosphatase protein at sites of contact with the endoplasmic reticulum, but other factors, including lysosomes, are also involved. Nagashima
et al.
now document an essential role for Golgi-derived vesicles bearing a specific lipid—phosphatidylinositol 4-phosphate, or PI(4)P—in the final steps of mitochondrial division. Disruption of PI(4)P production results in mitochondrial morphological defects indicative of an inability to complete fission.

Science
, this issue p.
1366
Endoplasmic reticulum–associated degradation regulates mitochondrial dynamics in brown adipocytes
Authors: Zhou Zhangsen , Torres Mauricio , Sha Haibo , Halbrook Christopher J. , Van den Bergh Françoise , Reinert Rachel B. , Yamada Tatsuya , Wang Siwen , Luo Yingying , Hunter Allen H. , Wang Chunqing , Sanderson Thomas H. , Liu Meilian , Taylor Aaron , Sesaki Hiromi , Lyssiotis Costas A. , Wu Jun , Kersten Sander , Beard Daniel A. , Qi Ling
Published: March 2020

Organelle cross-talk

Endoplasmic reticulum (ER)–associated degradation (ERAD) is a quality control mechanism that allows for targeted degradation of proteins in the ER. Zhou
et al.
found that a particular protein complex in ERAD, Sel1L-Hrd1, regulates the dynamics of another organelle, the mitochondrion, by altering ER-mitochondria contacts. Three-dimensional high-resolution imaging in brown adipocytes from cold-challenged mice revealed that defective ERAD led to the formation of enlarged and abnormally shaped mitochondria with perforating ER tubules. The authors explored the consequences of ERAD deficiency on mitochondrial function and thermogenesis, which provides insights into ERADmediated ER-mitochondrial cross-talk and advances our understanding of the physiological importance of interorganelle contact.

Science
, this issue p.
54
History, mass loss, structure, and dynamic behavior of the Antarctic Ice Sheet
Authors: Bell Robin E. , Seroussi Helene
Published: March 2020

Antarctica contains most of Earth’s fresh water stored in two large ice sheets. The more stable East Antarctic Ice Sheet is larger and older, rests on higher topography, and hides entire mountain ranges and ancient lakes. The less stable West Antarctic Ice Sheet is smaller and younger and was formed on what was once a shallow sea. Recent observations made with several independent satellite measurements demonstrate that several regions of Antarctica are losing mass, flowing faster, and retreating where ice is exposed to warm ocean waters. The Antarctic contribution to sea level rise has reached ~8 millimeters since 1992. In the future, if warming ocean waters and increased surface meltwater trigger faster ice flow, sea level rise will accelerate.
The Southern Ocean and its interaction with the Antarctic Ice Sheet
Authors: Holland David M. , Nicholls Keith W. , Basinski Aurora
Published: March 2020

The Southern Ocean exerts a major influence on the mass balance of the Antarctic Ice Sheet, either indirectly, by its influence on air temperatures and winds, or directly, mostly through its effects on ice shelves. How much melting the ocean causes depends on the temperature of the water, which in turn is controlled by the combination of the thermal structure of the surrounding ocean and local ocean circulation, which in turn is determined largely by winds and bathymetry. As climate warms and atmospheric circulation changes, there will be follow-on changes in the ocean circulation and temperature. These consequences will affect the pace of mass loss of the Antarctic Ice Sheet.
Dopamine promotes cognitive effort by biasing the benefits versus costs of cognitive work
Authors: Westbrook A. , van den Bosch R. , Määttä J. I. , Hofmans L. , Papadopetraki D. , Cools R. , Frank M. J.
Published: March 2020

Responsible use of psychostimulants

Psychostimulants have a place in the therapy of attentional disorders. However, they are also widely used off-label to enhance cognitive performance, and their mechanisms of action remain elusive. Westbrook
et al.
studied the effects of these drugs and concurrently measured striatal dopamine synthesis capacity in young, healthy participants (see the Perspective by Janes). They administered a placebo, methylphenidate (a dopamine and noradrenaline reuptake blocker), and sulpiride (a selective D2 receptor antagonist) while participants made explicit cost-benefit decisions about whether to engage in cognitive effort. Higher dopamine synthesis capacity in the caudate nucleus was associated with greater willingness to allocate cognitive effort. In addition, methylphenidate and sulpiride increased subjective values and motivation to work specifically for people with low dopamine synthesis capacity. Cognition-enhancing drugs may thus act at the motivational level rather than directly boosting cognition per se.

Science
, this issue p.
1362
; see also p.
1300
Resolving spatial and energetic distributions of trap states in metal halide perovskite solar cells
Authors: Ni Zhenyi , Bao Chunxiong , Liu Ye , Jiang Qi , Wu Wu-Qiang , Chen Shangshang , Dai Xuezeng , Chen Bo , Hartweg Barry , Yu Zhengshan , Holman Zachary , Huang Jinsong
Published: March 2020

Mapping perovskite trap states

The high efficiency of hybrid inorganic-organic perovskite solar cells is mainly limited by defects that trap the charge carriers and lead to unproductive recombination. Ni
et al.
used drive-level capacitance profiling to map the spatial and energetic distribution of trap states in both polycrystalline and single-crystal perovskite solar cells. The interface trap densities were up to five orders of magnitude higher than the bulk trap densities. Deep traps were mainly located at the interface of perovskites and hole-transport layers, where processing created a high density of nanocrystals. These results should aid efforts aimed at avoiding trap-state formation or passivating such defects.

Science
, this issue p.
1352
Time for NIH to lead on data sharing
Authors: Sim Ida , Stebbins Michael , Bierer Barbara E. , Butte Atul J. , Drazen Jeffrey , Dzau Victor , Hernandez Adrian F. , Krumholz Harlan M. , Lo Bernard , Munos Bernard , Perakslis Eric , Rockhold Frank , Ross Joseph S. , Terry Sharon F. , Yamamoto Keith R. , Zarin Deborah A. , Li Rebecca
Published: March 2020

A draft policy is generally supportive but should start mandating data sharing
Thermal light tunnels its way into electricity
Authors: Raman Aaswath P.
Published: March 2020

New devices convert low-temperature heat into electricity
Taking on all of the biomass for conversion
Authors: Zhang Tao
Published: March 2020

A catalytic process converts hardwood into phenol, propylene, and other valuable products
Shallow ponds prompt fitness-favorable species interbreeding
Authors: Zuk Marlene
Published: March 2020

Dry conditions liberate female toads to drive sexual selection of male mates
Stanley Cohen (1922–2020)
Authors: Carpenter Graham , Coffey Robert
Published: March 2020

Award-winning biochemist who shed light on cell growth
Tilorone, a Broad-Spectrum Antiviral for Emerging Viruses
Authors: Ekins Sean , Madrid Peter B.
Published: March 2020

Tilorone is a 50-year-old synthetic small-molecule compound with antiviral activity that is proposed to induce interferon after oral administration. This drug is used as a broad-spectrum antiviral in several countries of the Russian Federation. We have recently described activity
in vitro
and
in vivo
against the Ebola virus. After a broad screening of additional viruses, we now describe
in vitro
activity against Chikungunya virus (CHIK) and Middle Eastern respiratory syndrome coronavirus (MERS-CoV).
Constraints on rock uplift in the eastern Transverse Ranges and northern Peninsular Ranges and implications for kinematics of the San Andreas fault in the Coachella Valley, California, USA
Authors: Spotila James A. , Mason Cody C. , Valentino Joshua D. , Cochran William J.
Published: March 2020

The nexus of plate-boundary deformation at the northern end of the Coachella Valley in southern California (USA) is complex on multiple levels, including rupture dynamics, slip transfer, and three-dimensional strain partitioning on nonvertical faults (including the San Andreas fault). We quantify uplift of mountain blocks in this region using geomorphology and low-temperature thermochronometry to constrain the role of long-term vertical deformation in this tectonic system. New apatite (U-Th)/He (AHe) ages confirm that the rugged San Jacinto Mountains (SJM) do not exhibit a record of rapid Neogene exhumation. In contrast, in the Little San Bernardino Mountains (LSBM), rapid exhumation over the past 5 m.y. is apparent beneath a tilted AHe partial retention zone, based on new and previously published data. Both ranges tilt away from the Coachella Valley and have experienced minimal denudation from their upper surface, based on preservation of weathered granitic erosion surfaces. We interpret rapid exhumation at 5 Ma and the gentle tilt of the erosion surface and AHe isochrons in the LSBM to have resulted from rift shoulder uplift associated with extension prior to onset of transpression in the Coachella Valley. We hypothesize that the SJM have experienced similar rift shoulder uplift, but an additional mechanism must be called upon to explain the pinnacle-like form, rugged escarpment, and topographic disequilibrium of the northernmost SJM massif. We propose that this form stems from erosional resistance of the Peninsular Ranges batholith relative to more-erodible foliated metamorphic rocks that wrap around it. Our interpretations suggest that neither the LSBM nor SJM have been significantly uplifted under the present transpressive configuration of the San Andreas fault system, but instead represent relict highs due to previous tectonic and erosional forcing.
Widefield optical coherence tomography angiography for early detection and objective evaluation of proliferative diabetic retinopathy
Authors: Khalid Hagar , Schwartz Roy , Nicholson Luke , Huemer Josef , El-Bradey Mohamed Hosny , Sim Dawn A , Patel Praveen J , Balaskas Konstantinos , Hamilton Robin D , Keane Pearse A , Rajendram Ranjan
Published: March 2020

Purpose

To evaluate the utility of widefield optical coherence tomography angiography (WF-OCTA) compared with clinical examination in grading diabetic retinopathy in patients diagnosed clinically with proliferative diabetic retinopathy (PDR) or severe non-proliferative diabetic retinopathy (NPDR).

Design

This retrospective observational case series included patients diagnosed clinically with PDR or severe NPDR. Patients underwent standard clinical examination and WF-OCTA imaging (PLEX Elite 9000, Carl Zeiss Meditec AG) using 12×12 montage scans between August 2018 and January 2019. Two trained graders identified neovascularisation at the disc (NVD) and neovascularisation elsewhere (NVE) on WF-OCTA which were compared with the clinical examination, and to ultra-widefield fluorescein angiography (UWFA) when available.

Results

Seventy-nine eyes of 46 patients were evaluated. Of those, 57 eyes were diagnosed clinically with PDR, and 22 with severe NPDR. NVD was detected on OCTA-B scan as preretinal hyperreflective material (PRHM) in 39 eyes (100%) with evident flow signals in 79.5% compared with 51.3% detected clinically. We further classified NVD on OCTA into four subtypes and found that subtypes 1 and 2 could not be seen on clinical examination alone. WF-OCTA detected NVE in 81% of the cases compared with 55.7% detected clinically. Using WF-OCTA resulted in a higher percentage of PDR grading (88.6%) than on clinical examination (72.2%). When available, UWFA confirmed the WF-OCTA diagnosis in the majority of cases.

Conclusion

This study demonstrates that WF-OCTA has a higher detection rate of PDR than clinical examination. This suggests that this modality could be used non-invasively for the purpose of early detection and characterisation of neovascularisation.
Association between suicide reporting in the media and suicide: systematic review and meta-analysis
Authors: Niederkrotenthaler Thomas , Braun Marlies , Pirkis Jane , Till Benedikt , Stack Steven , Sinyor Mark , Tran Ulrich S , Voracek Martin , Cheng Qijin , Arendt Florian , Scherr Sebastian , Yip Paul S F , Spittal Matthew J
Published: March 2020

Objective

To examine the association between reporting on suicides, especially deaths of celebrities by suicide, and subsequent suicides in the general population.

Design

Systematic review and meta-analysis.

Data sources

PubMed/Medline, PsychInfo, Scopus, Web of Science, Embase, and Google Scholar, searched up to September 2019.

Review methods

Studies were included if they compared at least one time point before and one time point after media reports on suicide; follow-up was two months or less; the outcome was death by suicide; and the media reports were about non-fictional suicides. Data from studies adopting an interrupted time series design, or single or multiple arm before and after comparisons, were reviewed.

Results

31 studies were identified and analysed, and 20 studies at moderate risk of bias were included in the main analyses. The risk of suicide increased by 13% in the period after the media reported a death of a celebrity by suicide (rate ratio 1.13, 95% confidence interval 1.08 to 1.18; 14 studies; median follow-up 28 days, range 7-60 days). When the suicide method used by the celebrity was reported, there was an associated 30% increase in deaths by the same method (rate ratio 1.30, 95% confidence interval 1.18 to 1.44; 11 studies; median follow-up 28 days, range 14-60 days). For general reporting of suicide, the rate ratio was 1.002 (0.997 to 1.008; five studies; median follow-up 1 day, range 1-8 days) for a one article increase in the number of reports on suicide. Heterogeneity was large and partially explained by celebrity and methodological factors. Enhanced funnel plots suggested some publication bias in the literature.

Conclusions

Reporting of deaths of celebrities by suicide appears to have made a meaningful impact on total suicides in the general population. The effect was larger for increases by the same method as used by the celebrity. General reporting of suicide did not appear to be associated with suicide although associations for certain types of reporting cannot be excluded. The best available intervention at the population level to deal with the harmful effects of media reports is guidelines for responsible reporting. These guidelines should be more widely implemented and promoted, especially when reporting on deaths of celebrities by suicide.

Systematic review registration

PROSPERO CRD42019086559.
Development of a multivariable prediction model for plantar foot ulcer recurrence in high-risk people with diabetes
Authors: aan de Stegge Wouter B , Abu-Hanna Ameen , Bus Sicco A
Published: March 2020

Introduction

Forty per cent of people with diabetes who heal from a foot ulcer recur within 1 year. The aim was to develop a prediction model for plantar foot ulcer recurrence and to validate its predictive performance.

Research design and methods

Data were retrieved from a prospective analysis of 171 high-risk patients with 18 months follow-up. Demographic, disease-related, biomechanical and behavioral factors were included as potential predictors. Two logistic regression models were created. Model 1 for all recurrent plantar foot ulcers (71 cases) and model 2 for those ulcers indicated to be the result of unrecognized repetitive stress (41 cases). Ten-fold cross-validation, each including five multiple imputation sets, was used to internally validate the prediction strategy; model performance was assessed in terms of discrimination and calibration.

Results

The presence of a minor lesion, living alone, increased barefoot peak plantar pressure, longer duration of having a previous foot ulcer and less variation in daily stride count were predictors of the first model. The area under the receiver operating curve was 0.68 (IQR 0.61–0.80) and the Brier score was 0.24 (IQR 0.20–0.28). The predictors of the second model were presence of a minor lesion, longer duration of having a previous foot ulcer and location of the previous foot ulcer. The area under the receiver operating curve was 0.76 (IQR 0.66–0.87) and the Brier score was 0.17 (IQR 0.15–0.18).

Conclusions

These validated prediction models help identify those patients that are at increased risk of plantar foot ulcer recurrence and for that reason should be monitored more carefully and treated more intensively.
A two-part model to estimate inpatient, outpatient, prescribing and care home costs associated with atrial fibrillation in Scotland
Authors: Ciminata Giorgio , Geue Claudia , Langhorne Peter , Wu Olivia
Published: March 2020

Objective

This study aimed to estimate global inpatient, outpatient, prescribing and care home costs for patients with atrial fibrillation using population-based, individual-level linked data.

Design

A two-part model was employed to estimate the probability of resource utilisation and costs conditional on positive utilisation using individual-level linked data.

Settings

Scotland, 5 years following first hospitalisation for AF between 1997 and 2015.

Participants

Patients hospitalised with a known diagnosis of AF or atrial flutter.

Primary and secondary outcome measures

Inpatient, outpatient, prescribing and care home costs.

Results

The mean annual cost for a patient with AF was estimated at £3785 (95% CI £3767 to £3804). Inpatient admissions and outpatient visits accounted for 79% and 8% of total costs, respectively; prescriptions and care home stay accounted for 7% and 6% of total costs. Inpatient cost was the main driver across all age groups. While inpatient cost contributions (~80%) were constant between 0 and 84 years, they decreased for patients over 85 years. This is offset by increasing care home cost contributions. Mean annual costs associated with AF increased significantly with increasing number of comorbidities.

Conclusion

This study used a contemporary and representative cohort, and a comprehensive approach to estimate global costs associated with AF, taking into account resource utilisation beyond hospital care. While overall costs, considerably affected by comorbidity, did not increase with increasing age, care home costs increased proportionally with age. Inpatient admission was the main contributor to the overall financial burden of AF, highlighting the need for improved mechanisms of early diagnosis to prevent hospitalisations.
Knowing what the patient wants: a hospital ethnography studying physician culture in shared decision making in the Netherlands
Authors: Spinnewijn Laura , Aarts Johanna , Verschuur Sabine , Braat Didi , Gerrits Trudie , Scheele Fedde
Published: March 2020

Objectives

To study physician culture in relation to shared decision making (SDM) practice.

Design

Execution of a hospital ethnography, combined with interviews and a study of clinical guidelines. Ten-week observations by an insider (physician) and an outsider (student medical anthropology) observer. The use of French sociologist Bourdieu’s ’Theory of Practice’ and its description of habitus, field and capital, as a lens for analysing physician culture.

Setting

The gynaecological oncology department of a university hospital in the Netherlands. Observations were executed at meetings, as well as individual patient contacts.

Participants

Six gynaecological oncologists, three registrars and two specialised nurses. Nine of these professionals were also interviewed.

Main outcome measures

Common elements in physician habitus that influence the way SDM is being implemented.

Results

Three main elements of physician habitus were identified. First of all, the ‘emphasis on medical evidence’ in group meetings as well as in patient encounters. Second ’acting as a team’, which confronts the patient with the recommendations of a whole team of professionals. And lastly ‘knowing what the patient wants’, which describes how doctors act on what they think is best for patients instead of checking what patients actually want. Results were viewed in the light of how physicians deal with uncertainty by turning to medical evidence, as well as how the educational system stresses evidence-based medicine. Observations also highlighted the positive attitude doctors actually have towards SDM.

Conclusions

Certain features of physician culture hinder the correct implementation of SDM. Medical training and guidelines should put more emphasis on how to elicit patient perspective. Patient preferences should be addressed better in the patient workup, for example by giving them explicit attention first. This eventually could create a physician culture that is more helpful for SDM.
What helps and hinders the provision of healthcare that minimises treatment burden and maximises patient capacity? A qualitative study of stroke health professional perspectives
Authors: Kyle John , Skleparis Dimitris , Mair Frances S , Gallacher Katie I
Published: March 2020

Objectives

Treatment burden is the healthcare workload experienced by individuals with long-term conditions and the impact on well-being. Excessive treatment burden can negatively affect quality-of-life and adherence to treatments. Patient capacity is the ability of an individual to manage their life and health problems and is dependent on a variety of physical, psychological and social factors. Previous work has suggested that stroke survivors experience considerable treatment burden and limitations on their capacity to manage their health. We aimed to examine the potential barriers and enablers to minimising treatment burden and maximising patient capacity faced by health professionals and managers providing care to those affected by stroke.

Setting

Primary and secondary care stroke services in a single health board area in Scotland.

Participants

Face-to-face qualitative interviews with 21 participants including stroke consultants, nurses, physiotherapists, occupational therapists, speech and language therapists, psychologists, general practitioners and health-service managers.

Outcome measures

Data were analysed using thematic analysis to ascertain any factors that influence the provision of low-burden healthcare.

Results

Barriers and facilitators to the provision of healthcare that minimises treatment burden and maximises patient capacity were reported under five themes: healthcare system structure (e.g. care coordination and autonomous working); resources (e.g. availability of ward nurses and community psychologists); knowledge and awareness (e.g. adequate time and materials for optimal information delivery); availability of social care (e.g. waiting times for home adaptations or extra social support) and patient complexity (e.g. multimorbidity).

Conclusions

Our findings have important implications for the design and implementation of stroke care pathways, emphasising the importance of removing barriers to health professional provision of person-centred care. This work can inform the design of interventions aimed at nurturing autonomous working by health professionals, improving communication and care coordination or ensuring availability of a named person throughout the patient journey.
Finding the right balance with participation in exercise and sport for individuals with multiple sclerosis: protocol for a pre and post intervention feasibility study
Authors: Smith Moira , Williams Gavin , Barker Ruth
Published: March 2020

Introduction

Individuals with minimal disability from multiple sclerosis (MS) requested advice on finding the right balance, between too much and too little exercise, when participating in their choice of sport or exercise. To optimise exercise participation during the early stages of the disease, a flexible exercise participation programme (FEPP) has been developed. The FEPP is novel because it provides guidance and support for individuals with MS to participate and progress in theirpreferredsport or exercise. The primary objective was to assess the feasibility of the FEPP. The secondary objective was to assess the feasibility of a larger trial to demonstrate the efficacy of the FEPP.

Methods and analysis

A stage I feasibility study of the FEPP, using a single group preintervention/post-intervention design, will be conducted with 16 participants with minimal disability from MS (Expanded Disability Status Scale level of 0–3.5). The 12-week FEPP will guide participants to independently participate in their preferred sport or exercise at a location of their choice. Exercise progression will be guided by individual energy levels and a weekly telephone coaching session with a physiotherapist. Participation in exercise or sport will be recorded in parallel with assessment of disease biomarkers (plasma cytokines interleukin (IL)-2, IL-4, IL-6, IL-10, interferon (IFN)-γ and tumour necrosis factor (TNF)), subjective vitality and high-level mobility. Acceptability of the FEPP will be assessed using a sequential explanatory mixed methods design where the findings of a participant survey will inform the interview guide for a series of focus groups.

Feasibility of a larger trial will be assessed via process, resources, management and scientific metrics. Progression to a larger trial will depend on the achievement of specified minimum success criteria.

Ethics and dissemination

Ethical approval has been obtained for this study from the James Cook University Human Research Ethics Committee (H7956). Dissemination of findings is planned via peer-reviewed journals, conference presentations and media releases. The protocol date was 21 December 2019, V.1.

Trial registration number

The trial is registered with Australian New Zealand Clinical Trials Registry (ANZCTR), ACTRN12620000076976.
Modified paediatric preoperative risk prediction score to predict postoperative ICU admission in children: a retrospective cohort study
Authors: Lian Chunwei , Wang Pei , Fu Qingxia , Du Xudong , Wu Junzheng , Lian Qingquan , ShangGuan Wangning
Published: March 2020

Objective

To integrate intrinsic surgical risk into the paediatric preoperative risk prediction score (PRPS) model to construct a more comprehensive risk scoring system (modified PRPS) and improve the prediction accuracy of postoperative intensive care unit (ICU) admission in paediatric patients.

Design

This was a retrospective study conducted between 1 January and 30 December 2016. Data on age, American Society of Anaesthesiology physical status (ASA-PS), oxygen saturation, prematurity, non-fasted status, severity of surgery and immediate transfer to the ICU after surgery were collected. The modified PRPS was developed by logistic regression in the derivation cohort; it was tested and compared with the paediatric PRPS and ASA-PS by the Hosmer-Lemeshow test, the receiver operating characteristic (ROC) curve and Kappa analysis in the validation cohort.

Setting

Hospital-based study in China.

Participants

Paediatric patients (≤14 years) who underwent surgery under general anaesthesia were included, and those who needed reoperation due to surgical complications or stayed in the ICU preoperatively were excluded.

Main outcome measure

ICU admission rate, defined as any patients’ direct disposition from the operating room to the ICU immediately after the surgery.

Results

A total of 9261 paediatric patients were included in this study, with 418 patients admitted to the ICU. In the validation cohort, the modified PRPS model fit the test data well (deciles of risk goodness-of-fit χ2=6.84, p=0.077). The area under the ROC curve of the modified PRPS, paediatric PRPS and ASA-PS were 0.963, 0.941 and 0.870, respectively (p<0.05), and the Kappa values were 0.620, 0.286 and 0.267. Analyses in the cohort indicated that the modified PRPS was superior to the paediatric PRPS and ASA-PS.

Conclusions

The modified PRPS integrating intrinsic surgical risk shows better prediction accuracy than the previous PRPS.
The impact of level of neonatal care provision on outcomes for preterm babies born between 27 and 31 weeks of gestation, or with a birth weight between 1000 and 1500 g: a review of the literature
Authors: Ismail Abdul Qader Tahir , Boyle Elaine M , Pillay Thillagavathie
Published: March 2020

Objective

There is evidence that birth and care in a maternity service associated with a neonatal intensive care unit (NICU) is associated with improved survival in preterm babies born at <27 weeks of gestation. We conducted a systematic review to address whether similar gains manifested in babies born between 27+0 and 31+6 weeks (hereafter 27 and 31 weeks) of gestation, or in those with a birth weight between 1000 and 1500 g.

Methods

We searched Embase, Medline and CINAHL databases for studies comparing outcomes for babies born between 27 and 31 weeks or between 1000 and 1500 g birth weight, based on designation of the neonatal unit where the baby was born or subsequently cared for (NICU vs non-NICU setting). A modified QUIPS (QUality In Prognostic Studies) tool was used to assess quality.

Results

Nine studies compared outcomes for babies born between 27 and 31 weeks of gestation and 11 studies compared outcomes for babies born between 1000 and 1500 g birth weight. Heterogeneity in comparator groups, birth locations, gestational age ranges, timescale for mortality reporting, and description of morbidities facilitated a narrative review as opposed to a meta-analysis.

Conclusion

Due to paucity of evidence, significant heterogeneity and potential for bias, we were not able to answer our question—does place of birth or care affect outcomes for babies born between 27 and 31 weeks? This supports the need for large-scale research to investigate place of birth and care for babies born in this gestational age range.
Medical-attention injuries in community cricket: a systematic review
Authors: McLeod Geordie , O’Connor Siobhán , Morgan Damian , Kountouris Alex , Finch Caroline F , Fortington Lauren V
Published: March 2020

Objectives

The aim was to identify and describe outcomes from original published studies that present the number, nature, mechanism and severity of medically treated injuries sustained in community-level cricket.

Design

Systematic review.

Methods

Nine databases were systematically searched to December 2019 using terms “cricket*” and “injur*”. Original, peer-reviewed studies reporting injury for at least one injury descriptor (body region, nature of injury and/or mechanism of injury) in community-level cricketers of all ages were included. Qualitative synthesis, critical appraisal and descriptive summary results are reported within the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines.

Results

Six studies were included: five reported hospital-treated data and one reported insurance claims data. Two had a low risk of bias. In hospital-based studies, fractures were the most frequent injury type. Upper and lower limb injuries (age ≥15 years) and injuries to the head (age <15 years) were the most common body region injured. Being struck by the ball was the most common mechanism for injury presenting to hospitals. Children were also commonly struck by equipment. One study using insurance claims data reported soft tissue injuries as the main of injury type.

Conclusion

Hospital treatment data were most prominent, which emphasised injuries of a more serious nature or requiring acute care. These injuries were primarily fractures, dislocation/sprain and strains, bruising and open wounds with the majority resulting from players being struck by the ball. Research into whether properly fitted protective equipment, at an approved standard, is worn and is effective, is recommended.
Pterostilbene improves cardiac function in a rat model of right heart failure through modulation of calcium handling proteins and oxidative stress
Authors: Lacerda Denise , Türck Patrick , Campos-Carraro Cristina , Hickmann Alexandre , Ortiz Vanessa , Bianchi Sara , Belló-Klein Adriane , de Castro Alexandre Luz , Bassani Valquiria Linck , Araujo Alex Sander da Rosa
Published: March 2020

This study explored the effect of pterostilbene (PTS) complexed with hydroxypropyl-β-cyclodextrin (HPβCD) on right heart function, glutathione and glutaredoxin systems, and the expression of redox-sensitive proteins involved with regulation calcium levels in the experimental model of pulmonary arterial hypertension (PAH) induced by monocrotaline (MCT). After 7 days of PAH induction, rats received daily doses of the PTS:HPβCD complex (corresponding to 25, 50, or 100 mg·kg−1of PTS) or vehicle (control group, CTR0) (an aqueous solution containing HPβCD; CTR0 and MCT0 (MCT group that did not receive PTS treatment)) via oral administration for 2 weeks. The results showed that the PTS:HPβCD complex increased the content of reduced glutathione and the activity of glutathione-S-transferase and glutaredoxin in the right ventricle (RV) of MCT-treated rats in a dose-dependent manner. Additionally, at higher doses, it also prevented the reduction of stroke volume and cardiac output, prevented myocardial performance index (MPI) increase, reduced lipoperoxidation, reduced total phospholamban, and increased the expression of sarcoplasmic reticulum calcium ATPase in the RV of MCT-treated rats. These results demonstrate that the PTS:HPβCD complex has a dose-dependent antioxidant mechanism that results in improved cardiac function in experimental right heart failure. Our results open a field of possibilities to PTS administration as new therapeutic approach to conventional therapy for right ventricular dysfunction.

Novelty Pterostilbene complexed with hydroxypropyl-β-cyclodextrin could be a new therapeutic approach. Pterostilbene complexed with hydroxypropyl-β-cyclodextrin reestablishes redox homeostasis through glutathione metabolism modulation, leading to an improved MPI in pulmonary arterial hypertension-provoked right heart failure.
Towards high-order calculations of three-nucleon scattering in chiral effective field theory
Authors: Epelbaum E. , Golak J. , Hebeler K. , Kamada H. , Krebs H. , Meißner U.-G. , Nogga A. , Reinert P. , Skibiński R. , Topolnicki K. , Volkotrub Yu. , Witała H.
Published: March 2020

We discuss the current status of chiral effective field theory in the three-nucleon sector and present selected results for nucleon–deuteron scattering observables based on semilocal momentum-space-regularized chiral two-nucleon potentials together with consistently regularized three-nucleon forces up to third chiral order. Using a Bayesian model for estimating truncation errors, the obtained results are found to provide a good description of the experimental data. We confirm our earlier findings that a high-precision description of nucleon–deuteron scattering data below pion production threshold will require the theory to be pushed to fifth chiral order. This conclusion is substantiated by an exploratory study of selected short-range contributions to the three-nucleon force at that order, which, as expected, are found to have significant effects on polarization observables at intermediate and high energies. We also outline the challenges that will need to be addressed in order to push the chiral expansion of three-nucleon scattering observables to higher orders.
CONVERGENCE RATE AND GLOBAL MEAN WEIGHTED FIRST-PASSAGE TIME IN A 1D CHAIN NETWORK WITH A WEIGHTED ADDING REVERSE EDGE
Authors: CHEN TINGTING , DAI MEIFENG , HUANG FANG , FENG SHILIN
Published: March 2020

In this paper, a 1D chain network with a reverse weighted edge is introduced. We focus on studying the relationships including the convergence rate and the length, the convergence rate and weight of adding reverse edge relationships. Laplacian characteristic determinant is calculated and subsequently, the sum of the reciprocals of all nonzero Laplacian eigenvalues is obtained. Hence, the analytic expression of global mean weighted first-passage time (GMWFPT) can be deduced. The obtained results show that there exists a linearly positive relationship between GMWFPT and the weight [Formula: see text].
SYSTEMATIC DEFINITION OF COMPLEXITY ASSEMBLY IN FRACTAL POROUS MEDIA
Authors: JIN YI , WANG CHENG , LIU SHUNXI , QUAN WEIZHE , LIU XIAOKUN
Published: March 2020

Microstructures dominate the physical properties of fractal porous media, which means the clarification of complexity types and their assembly are of fundamental importance for static or dynamic purposes. In this work, we identified fractal porous media to dual-complexity systems composed of stationary and scale-invariant complexities as per fractal topography theory, and proposed an open mathematical framework to characterize complexity assembly in microstructures, realized the original complexity, such as random, multi-phase, and multi-type features by the quartet structure generation set (QSGS) algorithm, and unified the behavioral complexity, including the self-similar and self-affine properties by fractal topography model. For demonstration, the control mechanisms on the microstructures from different complexities are discussed, with their physical implications and relations to the physical properties of porous media clarified in principle. The results indicate that our framework is open to arbitrary original and behavioral complexities, and eases the modeling of multi-scale microstructures and the property estimation significantly.
NUMERICAL STUDY ON THE THERMAL PERFORMANCE OF A PHASE CHANGE HEAT EXCHANGER (PCHE) WITH INNOVATIVE FRACTAL TREE-SHAPED FINS
Authors: LIU XIANGDONG , LIU FEIFAN , DAI QIAOBO , YAO FENG , ZENG TIANJUN , ZHANG YULONG , YU CHENG
Published: March 2020

For alleviating energy shortage and environmental problems, it is of great importance to improve the energy charging and discharging efficiency of thermal energy storage systems. In this context, an innovative phase change heat exchanger (PCHE) with fractal tree-shaped fins is presented in this paper. A numerical investigation of the solidification behaviors in the PCHE with fractal tree-shaped fins is conducted. The dynamic temperature response and the solidification front evolution in the PCHE are analyzed and discussed. Furthermore, two evaluation criteria, including total solidification time and energy charging efficiency, are introduced to quantitatively study the effect of fin material on the solidification heat transfer characteristics. The results indicate that the fractal tree-shaped fin leads to a uniform temperature distribution of phase change material (PCM). The temperature response of fin is faster than that of PCM due to its high thermal conductivity. Moreover, the fractal tree-shaped fin breaks the restriction of gradually forward fashion of solidification front in the traditional PCHE and dramatically improves the energy discharging performance. The material of fractal tree-shaped fins is an essential factor affecting the solidification performance of the PCHE. The energy discharging performance of PCHE with pure copper fins is the best, whereas that with cupronickel fins is the worst. However, from the perspective of practical application, aluminum is the best potential alternative because of its relatively high thermal conductivity, lighter weight, and low cost.
IS ENTREPRENEURSHIP THE SOLUTION FOR FEMALE EMPOWERMENT IN SOUTH AFRICA
Authors: MUKORERA SOPHIA ZE
Published: March 2020

Gender inequality remains one of the most pressing socio-economic challenge in South Africa despite the presence of policy initiatives that target women for empowerment. The lack of consensus in the literature of a reliable and consistent measurement instrument of gender equality also makes it difficult to quantify and analyze female empowerment issues. The objective of the study was to estimate a measure for female empowerment, Gender Status Index, for South Africa and then use the index to analyze the relationship between entrepreneurship, economic growth and female empowerment. Using annual data from 1991 to 2017, an ARDL model of female empowerment (GSI), female entrepreneurship (Total female Self-Employment) and economic growth (Real GDP growth) was estimated. The study found that entrepreneurship has a positive impact on economic empowerment but no significant relationship on political and social empowerment. The study recommends more entrepreneurship institutions for female economic empowerment and ongoing policies initiatives that are more direct toward supporting female empowerment.