bluuebunny/crossref_metadata_2025 huggingface dataset:
Does community-based distribution of HIV self-tests increase uptake of HIV testing? Results of pair-matched cluster randomised trial in Zambia
Authors: Neuman Melissa , Hensen Bernadette , Mwinga Alwyn , Chintu Namwinga , Fielding Katherine L , Handima Nixon , Hatzold Karin , Johnson Cheryl , Mulubwa Chama , Nalubamba Mutinta , Otte im Kampe Eveline , Simwinga Musonda , Smith Gina , Tsamwa Dickson , Corbett Elizabeth Lucy , Ayles Helen
Published: January 2022

Objectives

Ending HIV by 2030 is a global priority. Achieving this requires alternative HIV testing strategies, such as HIV self-testing (HIVST) to reach all individuals with HIV testing services (HTS). We present the results of a trial evaluating the impact of community-based distribution of HIVST in community and facility settings on the uptake of HTS in rural and urban Zambia.

Design

Pair-matched cluster randomised trial.

Methods

In catchment areas of government health facilities, OraQuick HIVST kits were distributed by community-based distributors (CBDs) over 12 months in 2016–2017. Within matched pairs, clusters were randomised to receive the HIVST intervention or standard of care (SOC). Individuals aged ≥16 years were eligible for HIVST. Within communities, CBDs offered HIVST in high traffic areas, door to door and at healthcare facilities. The primary outcome was self-reported recent testing within the previous 12 months measured using a population-based survey.

Results

In six intervention clusters (population 148 541), 60 CBDs distributed 65 585 HIVST kits. A recent test was reported by 66% (1622/2465) in the intervention arm compared with 60% (1456/2429) in SOC arm (adjusted risk ratio 1.08, 95% CI 0.94 to 1.24; p=0.15). Uptake of the HIVST intervention was low: 24% of respondents in the intervention arm (585/2493) used an HIVST kit in the previous 12 months. No social harms were identified during implementation.

Conclusion

Despite distributing a large number of HIVST kits, we found no evidence that this community-based HIVST distribution intervention increased HTS uptake. Other models of HIVST distribution, including secondary distribution and community-designed distribution models, provide alternative strategies to reach target populations.

Trial registration number

ClinicalTrials.gov Registry (NCT02793804).
Pragmatic economic evaluation of community-led delivery of HIV self-testing in Malawi
Authors: Indravudh Pitchaya P , Fielding Katherine , Sande Linda A , Maheswaran Hendramoorthy , Mphande Saviour , Kumwenda Moses K , Chilongosi Richard , Nyirenda Rose , Johnson Cheryl C , Hatzold Karin , Corbett Elizabeth L , Terris-Prestholt Fern
Published: January 2022

Introduction

Community-based strategies can extend coverage of HIV testing and diagnose HIV at earlier stages of infection but can be costly to implement. We evaluated the costs and effects of community-led delivery of HIV self-testing (HIVST) in Mangochi District, Malawi.

Methods

This economic evaluation was based within a pragmatic cluster-randomised trial of 30 group village heads and their catchment areas comparing the community-led HIVST intervention in addition to the standard of care (SOC) versus the SOC alone. The intervention involved mobilising community health groups to lead 7-day HIVST campaigns including distribution of HIVST kits. The SOC included facility-based HIV testing services. Primary costings estimated economic costs of the intervention and SOC from the provider perspective, with costs annualised and measured in 2018 US$. A postintervention survey captured individual-level data on HIV testing events, which were combined with unit costs from primary costings, and outcomes. The incremental cost per person tested HIV-positive and associated uncertainty were estimated.

Results

Overall, the community-led HIVST intervention costed $138 624 or $5.70 per HIVST kit distributed, with test kits and personnel the main contributing costs. The SOC costed $263 400 or $4.57 per person tested. Individual-level provider costs were higher in the community-led HIVST arm than the SOC arm (adjusted mean difference $3.77, 95% CI $2.44 to $5.10; p<0.001), while the intervention effect on HIV positivity varied based on adjustment for previous diagnosis. The incremental cost per person tested HIV positive was $324 but increased to $1312 and $985 when adjusting for previously diagnosed self-testers or self-testers on treatment, respectively. Community-led HIVST demonstrated low probability of being cost-effective against plausible willingness-to-pay values, with HIV positivity a key determinant.

Conclusion

Community-led HIVST can provide HIV testing at a low additional unit cost. However, adding community-led HIVST to the SOC was not likely to be cost-effective, especially in contexts with low prevalence of undiagnosed HIV.

Trial registration number

NCT03541382.
The cost and intermediary cost-effectiveness of oral HIV self-test kit distribution across 11 distribution models in South Africa
Authors: Matsimela Katleho , Sande Linda Alinafe , Mostert Cyprian , Majam Mohammed , Phiri Jane , Zishiri Vincent , Madondo Celeste , Khama Stephen , Chidarikire Thato , d'Elbée Marc , Hatzold Karin , Johnson Cheryl , Terris-Prestholt Fern , Meyer-Rath Gesine
Published: January 2022

Background

Countries around the world seek innovative ways of closing their remaining gaps towards the target of 95% of people living with HIV (PLHIV) knowing their status by 2030. Offering kits allowing HIV self-testing (HIVST) in private might help close these gaps.

Methods

We analysed the cost, use and linkage to onward care of 11 HIVST kit distribution models alongside the Self-Testing AfRica Initiative’s distribution of 2.2 million HIVST kits in South Africa in 2018/2019. Outcomes were based on telephonic surveys of 4% of recipients; costs on a combination of micro-costing, time-and-motion and expenditure analysis. Costs were calculated from the provider perspective in 2019 US$, as incremental costs in integrated and full costs in standalone models.

Results

HIV positivity among kit recipients was 4%–23%, with most models achieving 5%–6%. Linkage to confirmatory testing and antiretroviral therapy (ART) initiation for those screening positive was 19%–78% and 2%–72% across models. Average costs per HIVST kit distributed varied between $4.87 (sex worker model) and $18.07 (mobile integration model), with differences largely driven by kit volumes. HIVST kit costs (at $2.88 per kit) and personnel costs were the largest cost items throughout. Average costs per outcome increased along the care cascade, with the sex worker network model being the most cost-effective model across metrics used (cost per kit distributed/recipient screening positive/confirmed positive/initiating ART). Cost per person confirmed positive for HIVST was higher than standard HIV testing.

Conclusion

HIV self-test distribution models in South Africa varied widely along four characteristics: distribution volume, HIV positivity, linkage to care and cost. Volume was highest in models that targeted public spaces with high footfall (flexible community, fixed point and transport hub distribution), followed by workplace models. Transport hub, workplace and sex worker models distributed kits in the least costly way. Distribution via index cases at facility as well as sex worker network distribution identified the highest number of PLHIV at lowest cost.
Joint effects of self-reported sleep and modifiable physical activity on risk of dyslipidaemia in women aged 45–55 years: a cross-sectional study
Authors: Du Sha , Su Yuenan , Zhang Dongxue , Wu Jing , Zheng Huiqiu , Wang Xuemei
Published: January 2022

Objectives

Modifiable physical activity (PA) plays an important role in dyslipidaemia risk in middle-aged women with sleep problems, especially perimenopausal women. We aimed to explore the joint effects of sleep and PA on the risk of dyslipidaemia in women aged 45–55 years, and the extent to which PA moderated the effect of sleep on the risk of dyslipidaemia.

Design

A cross-sectional study.

Setting

This study was based on the survey of Chronic Disease and Nutrition Monitoring in Adults in Inner Mongolia in 2015.

Participants

721 women aged 45–55 years were included.

Outcome measurement

PA was measured by the Global Physical Activity Questionnaire. Sleep was measured by questionnaire formulated by the Chinese Center for Disease Control and Prevention. Multivariate logistic regression analyses were performed to determine the joint effects of sleep and PA on dyslipidaemia risk. OR and 95% CI were reported.

Results

Among all participants, 60.6% had sleep problems, 29.0% had low PA and 41.1% had dyslipidaemia. Women with sleep problems had higher dyslipidaemia risk than women without sleep problems, irrespective of low, moderate or high PA, with OR (95% CI) of 4.24 (2.40 to 7.49), 3.14 (1.80 to 5.49) and 2.04 (1.20 to 3.48), respectively. PA could not completely attenuate the negative association between sleep and dyslipidaemia risk. With PA increased from low to high, the OR of dyslipidaemia decreased by 2.20. Women with sleep problems and low PA had higher risks of high total cholesterol, high triglyceride, low high-density lipoprotein cholesterol and high low-density lipoprotein cholesterol than women without sleep problems and high PA, with OR (95% CI) of 2.51 (1.18 to 5.35), 2.42 (1.23 to 4.74), 2.88 (1.44 to 5.74) and 2.52 (1.12 to 5.70), respectively.

Conclusions

Among women aged 45–55 years, the joint effects of self-reported sleep and PA on dyslipidaemia risk were more marked for sleep than for PA. Modifiable PA is a widely accessible and effective intervention to reduce the dyslipidaemia risk in women with sleep problems, particularly among perimenopausal women.
Training and redeployment of healthcare workers to intensive care units (ICUs) during the COVID-19 pandemic: a systematic review
Authors: Vera San Juan Norha , Clark Sigrún Eyrúnardóttir , Camilleri Matthew , Jeans John Paul , Monkhouse Alexandra , Chisnall Georgia , Vindrola-Padros Cecilia
Published: January 2022

Objectives

The rapid influx of patients with COVID-19 to intensive care at a rate that exceeds pre-existing staff capacity has required the rapid development of innovative redeployment and training strategies, which considered patient care and infection control. The aim of this study was to provide a detailed understanding of redeployment and training during the first year of the COVID-19 pandemic by capturing and considering the merit of the strategies enlisted and the experiences and needs of redeployed healthcare workers (HCWs).

Design

The review involved a systematic search of key terms related to intensive care AND training AND redeployment AND healthcare workers within nine databases (Medline, CINAHL, PsychINFO, MedRxiv, Web of Science, The Health Management Consortium database, Social Science Research Network, OpenGrey and TRIP), which took place on 16 July 2021. Analysis consisted of a synthesis of quantitative study outputs and framework-based thematic analysis of qualitative study outputs and grey literature. These results were then combined applying an interpretative synthesis. We followed Preferred Reporting Items for Systematic Reviews and Meta-Analyses, and the review protocol was available online.

Results

Forty papers were analysed. These took place primarily in the UK (n=15, 37.5%) and USA (n=17, 42.5%). Themes presented in the results are redeployment: implementation strategies and learning; redeployed HCWs’ experience and strategies to address their needs; redeployed HCWs’ learning needs; training formats offered and training evaluations; and future redeployment and training delivery. Based on this, key principles for successful redeployment and training were proposed.

Conclusions

The COVID-19 pandemic presents unique challenges to develop flexible redeployment strategies and deliver training promptly while following infection control recommendations. This review synthesises original approaches to tackle these challenges, which are relevant to inform the development of targeted and adaptative training and redeployment plans considering the needs of HCWs.
Effects of whole-body MRI on outpatient health service costs: a general-population prospective cohort study in Mecklenburg-Vorpommern, Germany
Authors: Schmidt Carsten Oliver , Sierocinski Elizabeth , Baumeister Sebastian-Edgar , Hegenscheid Katrin , Völzke Henry , Chenot Jean-François
Published: January 2022

Objective

Whole-body MRI (wb-MRI) is increasingly used in research and screening but little is known about the effects of incidental findings (IFs) on health service utilisation and costs. Such effects are particularly critical in an observational study. Our principal research question was therefore how participation in a wb-MRI examination with its resemblance to a population-based health screening is associated with outpatient service costs.

Design

Prospective cohort study.

Setting

General population Mecklenburg-Vorpommern, Germany.

Participants

Analyses included 5019 participants of the Study of Health in Pomerania with statutory health insurance data. 2969 took part in a wb-MRI examination in addition to a clinical examination programme that was administered to all participants. MRI non-participants served as a quasi-experimental control group with propensity score weighting to account for baseline differences.

Primary and secondary outcome measures

Outpatient costs (total healthcare usage, primary care, specialist care, laboratory tests, imaging) during 24 months after the examination were retrieved from claims data. Two-part models were used to compute treatment effects.

Results

In total, 1366 potentially relevant IFs were disclosed to 948 MRI participants (32% of all participants); most concerned masses and lesions (769 participants, 81%). Costs for outpatient care during the 2-year observation period amounted to an average of €2547 (95% CI 2424 to 2671) for MRI non-participants and to €2839 (95% CI 2741 to 2936) for MRI participants, indicating an increase of €295 (95% CI 134 to 456) per participant which corresponds to 11.6% (95% CI 5.2% to 17.9%). The cost increase was sustained rather than being a short-term spike. Imaging and specialist care related costs were the main contributors to the increase in costs.

Conclusions

Communicated findings from population-based wb-MRI substantially impacted health service utilisation and costs. This introduced bias into the natural course of healthcare utilisation and should be taken care for in any longitudinal analyses.
Breast screening atypia and subsequent development of cancer: protocol for an observational analysis of the Sloane database in England (Sloane atypia cohort study)
Authors: Jenkinson David , Freeman Karoline , Clements Karen , Hilton Bridget , Dulson-Cox Joanne , Kearins Olive , Stallard Nigel , Wallis Matthew G , Sharma Nisha , Kirwan Cliona , Pinder Sarah , Provenzano Elena , Shaaban Abeer M , Stobart Hilary , McDonnell Samantha , Thompson Alastair M , Taylor-Phillips Sian
Published: January 2022

Introduction

The National Health Service (NHS) Breast Screening Programme aims to detect cancer earlier when treatment is more effective but can harm women by over diagnosing and overtreating cancers which would never have become symptomatic. As well as breast cancer, a spectrum of atypical epithelial proliferations (atypia) can also be detected as part of screening. This spectrum of changes, while not cancer, may mean that a woman is more likely to develop breast cancer in the future. Follow-up of atypia is not evidence based. We currently do not know which atypia should be detected to avoid future cancer. This study will explore how atypia develops into breast cancer in terms of number of women, time of cancer development, cancer type and severity, and whether this varies for different types of atypia.

Methods and analysis

The Sloane cohort study began in April 2003 with ongoing data collection including atypia diagnosed through screening at screening units in the UK. The database for England has 3645 cases (24 September 2020) of epithelial atypia, with follow-up from 1 to 15 years. The outcomes include subsequent invasive breast cancer and the nature of subsequent cancer. Descriptive statistics will be produced. The observed rates of breast cancer at 1, 3 and 6 years for types of atypia will be reported with CIs, to enable comparison to women in the general population. Time to event methods will be used to describe the time to breast cancer diagnosis for the types of atypia, including flexible parametric modelling if appropriate. Patient representatives from Independent Cancer Patients’ Voice are included at every stage of the research.

Ethics and dissemination

The study has received research ethics approval from the University of Warwick Biomedical and Scientific Research Ethics Committee (BSREC 10/20–21, 8 October 2020), Public Health England office for data release approvals (ODR1718_313) and approval from the English Breast Research Advisory Committee (BSPRAC_031). The findings will be disseminated to breast screening clinicians (via journal publication and conference presentation), to the NHS Breast Screening Programme to update their guidelines on how women with atypia should be followed up, and to the general public.
Delivering outpatient virtual clinics during the COVID-19 pandemic: early evaluation of clinicians’ experiences
Authors: Vas Venessa , North Shirley , Rua Tiago , Chilton Daniella , Cashman Michaela , Malhotra Bharti , Garrood Toby
Published: January 2022

Background

The COVID-19 pandemic has put health systems across the world under significant pressure. In March 2020, a national directive was issued by the National Health Service (NHS) England instructing trusts to scale back face-to-face outpatient appointments, and rapidly implement virtual clinics.

Methods

A multidisciplinary team of change managers, analysts and clinicians were assembled to evaluate initial implementation of virtual clinics at Guy’s and St Thomas’ NHS Foundation Trust. In-depth interviews were conducted with clinicians who have delivered virtual clinics during the pandemic. An inductive thematic approach was used to analyse clinicians’ early experiences and identify enablers for longer term sustainability.

Results

Ninety-five clinicians from specialist services across the trust were interviewed between April and May 2020 to reflect on their experiences of delivering virtual clinics during Wave I COVID-19. Key reflections include the perceived benefits of virtual consultations to patients and clinicians; the limitations of virtual consultations compared with face-to-face consultations; and the key enablers that would optimise and sustain the delivery of virtual pathways longer term.

Conclusions

In response to the pandemic, outpatient services across the trust were rapidly redesigned and virtual clinics implemented. As a result, services have been able to sustain some level of service delivery. However, clinicians have identified challenges in delivering this model of care and highlighted enablers needed to sustaining the delivery of virtual clinics longer term, such as patient access to diagnostic tests and investigations closer to home.
Single-center experience using anakinra for steroid-refractory immune effector cell-associated neurotoxicity syndrome (ICANS)
Authors: Wehrli Marc , Gallagher Kathleen , Chen Yi-Bin , Leick Mark B , McAfee Steven L , El-Jawahri Areej R , DeFilipp Zachariah , Horick Nora , O'Donnell Paul , Spitzer Thomas , Dey Bimal , Cook Daniella , Trailor Michael , Lindell Kevin , Maus Marcela V , Frigault Matthew J
Published: January 2022

In addition to remarkable antitumor activity, chimeric antigen receptor (CAR) T-cell therapy is associated with acute toxicities such as cytokine release syndrome (CRS) and immune effector cell-associated neurotoxicity syndrome (ICANS). Current treatment guidelines for CRS and ICANS include use of tocilizumab, a monoclonal antibody that blocks the interleukin (IL)-6 receptor, and corticosteroids. In patients with refractory CRS, use of several other agents as third-line therapy (including siltuximab, ruxolitinib, anakinra, dasatinib, and cyclophosphamide) has been reported on an anecdotal basis. At our institution, anakinra has become the standard treatment for the management of steroid-refractory ICANS with or without CRS, based on recent animal data demonstrating the role of IL-1 in the pathogenesis of ICANS/CRS. Here, we retrospectively analyzed clinical and laboratory parameters, including serum cytokines, in 14 patients at our center treated with anakinra for steroid-refractory ICANS with or without CRS after standard treatment with tisagenlecleucel (Kymriah) or axicabtagene ciloleucel (Yescarta) CD19-targeting CAR T. We observed statistically significant and rapid reductions in fever, inflammatory cytokines, and biomarkers associated with ICANS/CRS after anakinra treatment. With three daily subcutaneous doses, anakinra did not have a clear, clinically dramatic effect on neurotoxicity, and its use did not result in rapid tapering of corticosteroids; although neutropenia and thrombocytopenia were common at the time of anakinra dosing, there were no clear delays in hematopoietic recovery or infections that were directly attributable to anakinra. Anakinra may be useful adjunct to steroids and tocilizumab in the management of CRS and/or steroid-refractory ICANs resulting from CAR T-cell therapies, but prospective studies are needed to determine its efficacy in these settings.
Evaluating soil water matric pressure and sorptivity relationship as affected by some properties of a clay soil
Authors: Karahan Gülay
Published: January 2022

Sorptivity (S) is the fundamental variable controlling the early infiltration process. Besides soil properties, soil initial water content (θi) and (or) matric pressure (hi) are key factors determining extent of S. Assessment of interrelationship among S, hi, and soil properties can provide a considerable insight into understanding the behaviour of dry soils to rainfall or irrigation water. This study was conducted to evaluate relationship between S and some selected soil parametric and morphometric properties within a range of hi. Sixteen undisturbed soil samples (5 cm id, 5 cm length) were taken from the topsoil (0–15 cm) of a paddy soil with clay texture. Sorptivity was measured with a mini-disc infiltrometer on the samples equilibrated at h, ranging from −20 to −1500 kPa. A parameter (η), representing the relationship between S and hi, was introduced. Correlation analysis was conducted between η and selected soil morphometric and parametric properties. Soil structure and clay content appeared the most important soil attributes influencing S–hirelation between −200 and −1500 kPa. The results provided a fundamental understanding on S–hi–soil properties interrelations in a clay soil. The methodology developed in this study can be used to evaluate S–hirelationship across different soils and scales.
Analysis of epidemic propagation using mean field theory on signed graphs
Authors: Su Hongwei , Zhang Zi-Wei , Wen Guoxing , Yan Guan
Published: January 2022

Over the past few decades, the study of epidemic propagation has caught widespread attention from many areas. The field of graphs contains a wide body of research, yet only a few studies explore epidemic propagation’s dynamics in “signed” networks. Motivated by this problem, in this paper we propose a new epidemic propagation model for signed networks, denoted as S-SIS. To explain our analysis, we utilized the mean field theory to demonstrate the theoretical results. When we compare epidemic propagation through negative links to those only having positive links, we find that a higher proportion of infected nodes actually spreads at a relatively small infection rate. It is also found that when the infection rate is higher than a certain value, the overall spreading in a signed network begins showing signs of suppression. Finally, in order to verify our findings, we apply the S-SIS model on Erdös–Rényi random network and scale-free network, and the simulation results is well consist with the theoretical analysis.
Optimized splitting of mixed-species RNA sequencing data
Authors: Song Xuan , Gao Hai Yun , Herrup Karl , Hart Ronald P.
Published: January 2022

Gene expression studies using xenograft transplants or co-culture systems, usually with mixed human and mouse cells, have proven to be valuable to uncover cellular dynamics during development or in disease models. However, the mRNA sequence similarities among species presents a challenge for accurate transcript quantification. To identify optimal strategies for analyzing mixed-species RNA sequencing data, we evaluate both alignment-dependent and alignment-independent methods. Alignment of reads to a pooled reference index is effective, particularly if optimal alignments are used to classify sequencing reads by species, which are re-aligned with individual genomes, generating [Formula: see text] accuracy across a range of species ratios. Alignment-independent methods, such as convolutional neural networks, which extract the conserved patterns of sequences from two species, classify RNA sequencing reads with over 85% accuracy. Importantly, both methods perform well with different ratios of human and mouse reads. While non-alignment strategies successfully partitioned reads by species, a more traditional approach of mixed-genome alignment followed by optimized separation of reads proved to be the more successful with lower error rates.
The Ecological Significance of Aphid Cornicles and Their Secretions
Authors: Michaud J.P.
Published: January 2022

Aphid cornicles are abdominal appendages that secrete an array of volatile and nonvolatile compounds with diverse ecological functions. The emission of alarm pheromones yields altruistic benefits for clone-mates in the aphid colony, which is essentially a superorganism with a collective fate. Secreted droplets also contain unsaturated triglycerides, fast-drying adhesives that can be lethal when smeared on natural enemies but more often impede their foraging efficiency. The longest cornicles have evolved in aphids that feed in exposed locations and are likely used to scent-mark colony intruders. Reduced cornicles are associated with reliance on alternative defenses, such as the secretion of protective waxes or myrmecophily. Root-feeding and gall-forming lifestyles provide protected feeding sites and are associated with an absence of cornicles. In some eusocial gall-formers, soldier morphs become repositories of cornicle secretion used to defend the gall, either as menopausal apterae that defend dispersing alatae or as sterile first instars that dispatch predators with their stylets and use cornicle secretions as a construction material for gall repair. Collectively, the evidence is consistent with an adaptive radiation of derived cornicle functions molded by the ecological lifestyle of the aphid lineage.
Neuroecology of Alcohol Preference in Drosophila
Authors: Keesey Ian W. , Hansson Bill S.
Published: January 2022

In this review, we highlight sources of alcohols in nature, as well as the behavioral and ecological roles that these fermentation cues play in the short lifespan of Drosophila melanogaster. With a focus on neuroethology, we describe the olfactory detection of alcohol as well as ensuing neural signaling within the brain of the fly. We proceed to explain the plethora of behaviors related to alcohol, including attraction, feeding, and oviposition, as well as general effects on aggression and courtship. All of these behaviors are shaped by physiological state and social contexts. In a comparative perspective, we also discuss inter- and intraspecies differences related to alcohol tolerance and metabolism. Lastly, we provide corollaries with other dipteran and coleopteran insect species that also have olfactory systems attuned to ethanol detection and describe ecological and evolutionary directions for further studies of the natural history of alcohol and the fly.
Real-Time Infectious Disease Modeling to Inform Emergency Public Health Decision Making
Authors: Bershteyn Anna , Kim Hae-Young , Braithwaite R. Scott
Published: January 2022

Infectious disease transmission is a nonlinear process with complex, sometimes unintuitive dynamics. Modeling can transform information about a disease process and its parameters into quantitative projections that help decision makers compare public health response options. However, modelers face methodologic challenges, data challenges, and communication challenges, which are exacerbated under the time constraints of a public health emergency. We review methods, applications, challenges and opportunities for real-time infectious disease modeling during public health emergencies, with examples drawn from the two deadliest pandemics in recent history: HIV/AIDS and coronavirus disease 2019 (COVID-19).
Effects of Enhanced Hole Mobility on Electrochemically Synthesized p-Type CuAlO2 Films for Photoelectrochemical Hydrogen Production from Water
Authors: Choi Seung Yo , Park Hyunwoong
Published: January 2022

Delafossite CuAlO2 photoelectrodes are synthesized via the electrodeposition of Cu(II) and Al(III) onto fluorine-doped tin oxide (FTO) substrates in water and dimethylsulfoxide (DMSO) solvents, followed by annealing in air and Ar. The surface property, crystalline structure, and photoelectrochemical (PEC) performance of as-synthesized samples are significantly affected by the synthetic condition. Optimized CuAlO2 electrodes (synthesized in DMSO and annealed in Ar) possess suitable energetics for H2 production under sunlight (an optical bandgap of ~1.4 eV and a conduction band level of -0.24 VRHE). They exhibit a photocurrent onset potential of ~+0.9 VRHE along with a Faradaic efficiency of ~70% at +0.3 VRHE in an alkaline solution (1 M KOH) under simulated sunlight (AM 1.5; 100 mW×cm-2). The addition of sacrificial hole scavengers (sulfide and sulfite) significantly improves the PEC performance of CuAlO2 by a factor of eight, along with providing a Faradaic efficiency of ~100%. This indicates that the hole transfer limits the overall PEC performance. This issue is addressed by employing a ~150 nm-thick Au film-coated FTO substrate for the CuAlO2 deposition. In the absence of hole scavengers, the H2 production with the Au-underlain CuAlO2 photoelectrode (Au/CuAlO2) was three-fold higher than that with bare CuAlO2, while the Faradaic efficiencies at +0.3 and +0.55 VRHE were ~100%. The time-resolved photoluminescence emission decay spectra of the CuAlO2 and Au/CuAlO2 confirmed the facilitated charge transfer in the latter.
In Situ Exsolved Core-Shell Nanoparticles on Perovskite Parent: A Novel High-Performance Anode for Solid Oxide Fuel Cells
Authors: Hou Nianjun , Zhao Yicheng , Li Yongdan
Published: January 2022

Solid oxide fuel cells (SOFCs) with a high energy conversion efficiency and low emissions are considered as promising substitutes for traditional thermal power devices[
1
,2]. However, the conventional Ni based anode suffers from agglomeration, sulfur poisoning and carbon coking with hydrocarbon fuels, which limit its application[3]. Various alternative materials have been studied as promising SOFC anodes. Meanwhile, in situ exsolution has been developed as a fabrication strategy to prepare perovskite oxides with uniformly dispersed nanometallic particles[4]. Recently, A-site ordered PrBaMn2O5+d has been reported as a promising anode with high electrical conductivity and good catalytic activity for the electrochemical oxidation of both hydrogen and hydrocarbons[5]. In this work, La0.5Ba0.5Mn1-2xCoxFexO3-δ (x=0, 0.05, 0.1) has been synthesized with the Pechini method and investigated as an anode material of SOFCs with H2 and methane as fuels. The structure of the anode converts from a mixture of cubic and hexagonal phases to a perovskite structure with core-shell nanoparticles on the surface after reduction. The in situ exsolution process of the metals on the B sites is studied with an X-ray photoelectron spectrometer, a thermogravimetric analyzer and a transmission electron microscope. The results of the electrochemical tests demonstrate that the doping of Co and Fe into B sites effectively improve the performance of the single cell with H2 as the fuel. A single cell with a 2CF-LBM anode layer and a 300-μm La0.8Sr0.2Ga0.8Mg0.2O3-δ electrolyte layer exhibits a maximum power density (P
max) of 98, 210, 383, 653 and 1479 mW cm-2 with wet H2 as the fuel at 650, 700, 750, 800 and 850 oC, respectively, and achieves a peak power density of 503 mW cm-2 at 850 oC when fueled with wet CH4. Moreover, the 2CF-LBM anode exhibits a high coking resistance, and no remarkable degradation of the performance is observed when the cell is operated with methane as the fuel for more than 200 hours.

Keywords: Solid oxide fuel cell; Perovskite; Anode; In situ exsolution

Table 1. Abbreviations of various anode materials and the maximum output power densities of the cells fed with H2 and CH4 at 850 oC

Anode composition
Abbreviation

P
max,H2 (mW cm-2)

P
max,CH4 (mW cm-2)

La0.5Ba0.5MnO3-δ

LBM
962

336

La0.5Ba0.5Mn0.9Co0.05Fe0.05O3-δ

1CF-LBM
1241

389

La0.5Ba0.5Mn0.8Co0.1Fe0.1O3-δ

2CF-LBM
1479
503

Figure 1. (a) Bright-field TEM image, (b) HAADF imagine with the EDS linear scanning and (c) EDS elemental map of the reduced 2CF-LBM; (d) I-V and I-P curves of the single cell in 650-850 oC with H2 as fuel.

References

S. Tao, J.T. Irvine, Nature materials 2003, 2, 320-323.

Z. Shao, S.M. Haile, Nature 2004, 431, 170-173.

X.M. Ge, S.H. Chan, Q.L Liu, et al., Advanced energy materials 2012, 2, 1156-1181.

D. Neagu, G. Tsekouras, D. N. Miller, et al., Nature Chemistry 2013, 5, 916-923.

S. Sengodan, S. Choi, A. Jun, et al., Nature materials 2015, 14, 205-209.

Figure 1
Using Dynamic Stress Analysis to Quantify Adsorbate-Induced Surface Stress
Authors: Stafford Gery R. , Bertocci Ugo
Published: January 2022

Wafer curvature and cantilever bending techniques have been used by the electrochemical community to examine stress development during electrochemical processing. Surface stress changes as low as 10−3 N/m can typically be resolved from cantilever electrodes immersed in solution and under potential control. Such resolution makes this measurement useful for examining virtually all aspects of electrochemistry; i.e., electrocapillarity, adsorption processes, underpotential deposition, electrodeposition, etc. Often these processes occur either simultaneously or in rapid succession and we are often limited to measuring the influence of the dominant process in the time-scale of the experiment. In the case of electrocapillarity (charge-induced stress), the figure of merit is the stress-charge coefficient (ς) which captures the fundamental surface mechanics associated with charging the electrode surface. It has been well documented in the literature that ς is influenced by the anion in solution and its concentration.1,2 However, a steady state measurement cannot separate the contributions of anion adsorption from that of simple capacitive charging.

Similar to electrochemical impedance spectroscopy (EIS) where electrochemical processes with different characteristic time constants can be separated, dynamic stress analysis (DSA) allows us to study the dynamics of any particular stress-generating process and link the stress to specific electrochemical and surface phenomena. We have demonstrated the technique by examining the electrocapillarity of both Pt and Au in HClO4 electrolyte.3,4 ς can be obtained from the following equation,

ς = jωYsZe

where Ze is the electrochemical impedance, Ys is the stress admittance (with units of N/(V-m), ω is the angular frequency, and j =√-1. In order to include adsorbate-induced contributions to the surface stress, one considers an equivalent circuit that adequately describes both the double layer and adsorption contributions to the electrochemical impedance. One can then obtain unique stress-charge coefficients that capture both electrocapillarity and anion adsorption as a function of potential. This will be demonstrated using (111)-textured Au cantilever electrodes in both sulfate and perchlorate electrolyte.

References

W. Haiss, R.J. Nichols, J.K. Sass, and K.P. Charle, J. Electroanal. Chem., 452, 199, (1998).

R.N. Viswanath, D. Kramer, and J. Weissmüller, Langmuir, 21, 4604 (2005).

M. C. Lafouresse, U. Bertocci, C. R. Beauchamp, and G. R. Stafford, J. Electrochem. Soc. 159, H816 (2012).

M. C. Lafouresse, U. Bertocci, and G. R. Stafford, J. Electrochem. Soc. 160, H636 (2013).
Is “not different” enough to conclude similar cardiovascular responses across sexes?
Authors: O’Brien Myles W. , Kimmerly Derek S.
Published: January 2022

The number of research studies investigating whether similar or different cardiovascular responses or adaptations exist between males and females is increasing. Traditionally, difference-based statistical methods, e.g., t test, ANOVA, etc., have been implemented to compare cardiovascular function between males and females, with a P value of >0.05 used to denote similarity between sexes. However, an absence of evidence, i.e., large P value, is not evidence of absence, i.e., no sex differences. Equivalence testing determines whether two measures or groups provide statistically equivalent outcomes, in that they differ by less than an “ideally prespecified” smallest effect size of interest. Our perspective discusses the applicability and utility of integrating equivalence testing when conducting sex comparisons in cardiovascular research. An emphasis is placed on how cardiovascular researchers may conduct equivalence testing across multiple study designs, e.g., cross-sectional comparisons, repeated-measures intervention, etc. The strengths and weaknesses of this statistical tool are discussed. Equivalence analyses are relatively simple to conduct, may be used in conjunction with traditional hypothesis testing to interpret findings, and permit the determination of statistically equivalent responses between sexes. We recommend that cardiovascular researchers consider implementing equivalence testing to better our understanding of similar and different cardiovascular processes between sexes.
G
-Chain Mixing and
G
-Chain Transitivity in Metric G-Space
Authors: Ji Zhanjiang
Published: January 2022

Firstly, we introduce the concept of

G

-chain mixing,

G

-mixing, and

G

-chain transitivity in metric

G

-space. Secondly, we study their dynamical properties and obtain the following results. (1) If the map

f

has the

G

-shadowing property, then the map

f

is

G

-chain mixed if and only if the map

f

is

G

-mixed. (2) The map

f

is

G

-chain transitive if and only if for any positive integer

k
≥
2

, the map

f

k

is

G

-chain transitive. (3) If the map

f

is

G

-pointwise chain recurrent, then the map

f

is

G

-chain transitive. (4) If there exists a nonempty open set

U

satisfying

G

U

=
U

,

U
¯

≠
X

, and

f

U
¯

⊂
U

, then we have that the map

f

is not

G

-chain transitive. These conclusions enrich the theory of

G

-chain mixing,

G

-mixing, and

G

-chain transitivity in metric

G

-space.
Improved Handover Authentication in Fifth-Generation Communication Networks Using Fuzzy Evolutionary Optimisation with Nanocore Elements in Mobile Healthcare Applications
Authors: Divakaran J. , Prashanth S. K. , Mohammad Gouse Baig , Shitharth Dr , Mohanty Sachi Nandan , Arvind C. , Srihari K. , Abdullah R. Yasir , Sundramurthy Venkatesa Prabhu
Published: January 2022

Authentication is a suitable form of restricting the network from different types of attacks, especially in case of fifth-generation telecommunication networks, especially in healthcare applications. The handover and authentication mechanism are one such type that enables mitigation of attacks in health-related services. In this paper, we model an evolutionary model that uses a fuzzy evolutionary model in maintaining the handover and key management to improve the performance of authentication in nanocore technology-based 5G networks. The model is designed in such a way that it minimizes the delays and complexity while authenticating the networks in 5G networks. The attacks are mitigated using an evolutionary model when it is trained with the relevant attack datasets, and the model is validated to mitigate the attacks. The simulation is conducted to test the efficacy of the model, and the results of simulation show that the proposed method is effective in improving the handling and authentication and mitigation against various types of attacks in mobile health applications.
GP96 and SMP30 Protein Priming of Dendritic Cell Vaccination Induces a More Potent CTL Response against Hepatoma
Authors: Huang Rongshi , Pan Jian , Zhang Yaoyao , Qin Qiuhong , Chao Naixia , Huang Tianming , Chen Chengxiao , Zhao Feilan , Luo Guorong
Published: January 2022

Heat-shock protein (HSP) GP96 is a well-known adjuvant in immunotherapy. It belongs to the HSP90 family. Our previous study demonstrated that DC pulsed with recombinant senescence marker protein 30 (SMP30) could induce cytotoxic T lymphocytes (CTLs) against liver cancer cells in vitro. In this study, SMP30 and GP96 were subcloned into lentiviruses and transfected into DCs from healthy donors. We included six groups: the GP96-SMP30 group, GP96 group, SMP30 group, DC group, empty vector control group, and hepatoma extracted protein group. We used ELISA to detect cytokines and flow cytometry to assess CD80 and CD86 on DCs and the effect of CTLs. Our vector design was considered successful and further studied. In the SMP30 group, DC expresses more CCR7 and CD86 than the control group; in the SMP30+GP96 group, DC express more CCR7, CD86, and CD80 than the control group. Transfected DCs secreted more TNF-α and interferon-β and induced more CTLs than control DCs. SMP30 + GP96 effectively stimulated the proliferation of T cells compared with control treatment (

P

 < 0.01). We detected the cytokines TNF-α, TNF-β, IL-12, and IFN (α, β, and γ) via ELISA (Figure 5) and verified the killing effect via FCM. Four E : T ratios (0 : 1, 10 : 1, 20 : 1, and 40 : 1) were tested. The higher the ratio was, the better the effects were. We successfully constructed a liver cancer model and tested the CTL effect in each group. The GP96 + SMP30 group showed a better effect than the other groups. GP96 and SMP30 can stimulate DCs together and produce more potent antitumor effects. Our research may provide a new efficient way to improve the therapeutic effect of DC vaccines in liver cancer.
A Prospective Study of Azilsartan Medoxomil in the Treatment of Patients with Essential Hypertension and Type 2 Diabetes in Asia
Authors: Deerochanawong Chaicharn , Chang Kuan-Cheng , Woo Yu Cho , Lai Wen-Ter , Chutinet Aurauma
Published: January 2022

This phase 4 study evaluated the efficacy and safety of azilsartan medoxomil (AZL-M) in patients with essential hypertension and type 2 diabetes mellitus (T2DM) in Hong Kong, Taiwan, and Thailand. This was a prospective, multicenter, single-arm, open-label study with patients aged 18–75 years with T2DM and essential hypertension and on stable treatment for T2DM. Patients with uncontrolled hypertension were treated with AZL-M 40 mg daily, with the option to uptitrate to 80 mg at 6 weeks. In all, 380 of the 478 patients screened in Hong Kong, Taiwan, and Thailand were enrolled. At week 6, 97 patients (25.5%) were titrated up to AZL-M 80 mg based on BP readings. At 12 weeks, 54.8% of patients reached the blood pressure (BP) goal of <140/85 mm Hg by trough sitting clinic BP (primary endpoint), and 62.8% and 27.0% achieved a BP of <140/90 mm Hg and <130/80 mm Hg, respectively. The efficacy of AZL-M over 12 weeks was also seen in different age and body mass index groups. The incidence of treatment emergent adverse events (TEAEs) was 12.9% before 6 weeks and 16.1% after 6 weeks, and they were mostly mild in severity. The most frequent TEAE was dizziness (4.7%). The incidence of TEAEs leading to study drug discontinuation (4.5%) and drug-related TEAEs (5.0% before 6 weeks; 3.9% after 6 weeks) was low. In patients with essential hypertension and T2DM in Asia, treatment with AZL-M indicated a favorable efficacy and safety profile in achieving target BP.
Brain Functional Network Analysis of Patients with Primary Angle-Closure Glaucoma
Authors: Liu Dan , Gao Junwei , You Tao , Li Shenghong , Cai Fengqin , Pei Chonggang , Zeng Xianjun
Published: January 2022

Objectives. Recent resting-state functional magnetic resonance imaging (fMRI) studies have focused on glaucoma-related neuronal degeneration in structural and spontaneous functional brain activity. However, there are limited studies regarding the differences in the topological organization of the functional brain network in patients with glaucoma. In this study, we aimed to assess both potential alterations and the network efficiency in the functional brain networks of patients with primary angle-closure glaucoma (PACG). Methods. We applied resting-state fMRI data to construct the functional connectivity network of 33 patients with PACG (

54.21
±
7.21
 
years

) and 33 gender- and age-matched healthy controls (

52.42
±
7.80
 
years

). The differences in the global and regional topological brain network properties between the two groups were assessed using graph theoretical analysis. Partial correlations between the altered regional values and clinical parameters were computed for patients with PACG. Results. No significant differences in global topological measures were identified between the two groups. However, significant regional alterations were identified in the patients with PACG, including differences within visual and nonvisual (somatomotor and cognition-emotion) regions. The normalized clustering coefficient and normalized local efficiency of the right superior parietal gyrus were significantly correlated with the retinal fiber layer thickness (RNFLT) and the vertical cup to disk ratio (V C/D). In addition, the normalized node betweenness of the left middle frontal gyrus (orbital portion) was significantly correlated with the V C/D in the patients with PACG. Conclusions. Our results suggest that regional inefficiency with decrease and compensatory increase in local functional properties of visual and nonvisual nodes preserved the brain network of the PACG at the global level.
Motor Imagery EEG Decoding Based on New Spatial-Frequency Feature and Hybrid Feature Selection Method
Authors: Tang Yuan , Zhao Zining , Zhang Shaorong , Li Zhi , Mo Yun , Guo Yan
Published: January 2022

Feature extraction and selection are important parts of motor imagery electroencephalogram (EEG) decoding and have always been the focus and difficulty of brain-computer interface (BCI) system research. In order to improve the accuracy of EEG decoding and reduce model training time, new feature extraction and selection methods are proposed in this paper. First, a new spatial-frequency feature extraction method is proposed. The original EEG signal is preprocessed, and then the common spatial pattern (CSP) is used for spatial filtering and dimensionality reduction. Finally, the filter bank method is used to decompose the spatially filtered signals into multiple frequency subbands, and the logarithmic band power feature of each frequency subband is extracted. Second, to select the subject-specific spatial-frequency features, a hybrid feature selection method based on the Fisher score and support vector machine (SVM) is proposed. The Fisher score of each feature is calculated, then a series of threshold parameters are set to generate different feature subsets, and finally, SVM and cross-validation are used to select the optimal feature subset. The effectiveness of the proposed method is validated using two sets of publicly available BCI competition data and a set of self-collected data. The total average accuracy of the three data sets achieved by the proposed method is 82.39%, which is 2.99% higher than the CSP method. The experimental results show that the proposed method has a better classification effect than the existing methods, and at the same time, feature extraction and feature selection time also have greater advantages.