bluuebunny/crossref_metadata_2025 huggingface dataset:
Socioenvironmental criteria and postoperative complications in ambulatory surgery in a French university hospital: a prospective cross-sectional observational study
Authors: Mihailescu Sorina-Dana , Maréchal Isabelle , Thillard Denis , Gillibert André , Compère Vincent
Published: November 2020

Background

Ambulatory surgery lowers hospitalisation costs, shortens the time to return to work but requires caution regarding socioenvironmental risk factors for complications and rehospitalisation.

Methods

This was a single-centre prospective cross-sectional observational study conducted in a university hospital centrein January 2017. The primary objective was to assess the rate of conversion from ambulatory surgery to conventional hospitalisation or emergency department visit within 30 days following discharge from ambulatory unit. Secondary objectives were to describe the socioenvironmental characteristics of outpatients and to identify risk factors for severe postoperative complications.

Results

598 outpatients were included. The most represented surgical specialties were ophthalmology (23.5%), gynaecology (19%) and orthopaedics (17.7%). Patients’ mean age was 50.8 years (SD, 19.8) and the male/female sex ratio was 0.68. There were 22 (3.68%, 95% CI 2.32% to 5.52%) severe complications, including 11 (1.84%, 95% CI 0.92% to 3.27%) conversions to conventional hospitalisation and 11 (1.84%) conversions to emergency department visit, 3 of which led to readmission. Regarding socioenvironmental characteristics, 116 outpatients (19.7%) lived alone but were not isolated and 15 (2.6%) lived alone and were socially isolated. Following ambulatory surgery, 9 outpatients (1.6%) returned home on foot, 20 (3.4%) by public transportation and 8 (1.4%) drove home; 133 outpatients (13.7%) were alone the first night following surgery. Severe complication rates were not significantly different according to socioenvironmental subgroups.

Conclusion

In our study, the prevalence of severe complications was low, conforming to the literature. The study was underpowered to estimate the effect of socioenvironmental variables.
Effects of behavioural parent training for children with attention-deficit/hyperactivity disorder on parenting behaviour: a protocol for an individual participant data meta-analysis
Authors: Steenhuis Laura , Groenman Annabeth P , Hoekstra Pieter J , Hornstra Rianne , Luman Marjolein , van der Oord Saskia , van den Hoofdakker Barbara J
Published: November 2020

Introduction

Behavioural parent training (BPT) is a well-established treatment for children with attention-deficit/hyperactivity disorder (ADHD). BPT is based on the hypothesis that improvements in parenting are mediators of improvements in children’s behaviours. However, meta-analyses show considerate heterogeneity in effects of BPT on child outcomes, and meta-analyses on parenting outcomes are scarce. Also, few studies have investigated parenting factors as mediators of child outcomes. This study aims to examine the effects and moderators of BPT on parenting outcomes and whether improvements in parenting mediate amelioration of behaviour and impairment in children with ADHD.

Methods and analyses

We will conduct an individual participant data meta-analysis (IPDMA), making use of individual data of existing trials, and giving the opportunity for highly powered moderator analyses. This IPDMA will be performed by the Psychosocial ADHD INTervention (PAINT) collaboration. We will include randomised controlled trials of BPT, for individuals with ADHD below 18 years old. Systematic searches have been performed to locate relevant papers. Authors are currently contacted to share their data with the PAINT-IPDMA project. We will examine effects of BPT on parenting outcomes (eg, positive and negative parenting, management of affect, perceived parenting competence, parenting stress), moderators of these effects (eg, parental depression, parenting stress, severity of the child’s ADHD symptoms) and subsequently perform mediation analyses where parenting outcomes are modelled as mediators of child outcomes (eg, symptoms and severity of ADHD, comorbid psychopathology and impairment).

Ethics and dissemination

We will include data from randomised control trials for which ethical approval has been received and consent forms have been signed. Deidentified data will be provided by the original investigators. We aim to disseminate our findings through peer-reviewed scientific journals, presentations at (inter)national scientific meetings, newsletters, the website of our project and the Dutch academic workspace ADHD.

PROSPERO registration number

CRD42017069877.
3D-printed brace in the treatment of adolescent idiopathic scoliosis: a study protocol of a prospective randomised controlled trial
Authors: Zhang Youyu , Liang Junyang , Xu Nanfang , Zeng Lin , Du Chaojun , Du Yaoxu , Zeng Yan , Yu Miao , Liu Zhongjun
Published: November 2020

Introduction

Adolescent idiopathic scoliosis (AIS) is a three-dimensional deformity of the spine. Brace treatment is effective for eligible patients with AIS and the effectiveness is significantly correlated with the average brace-wear time per day. Three-dimensional (3D) printing technology is a recent advancement that offers unique opportunities for biomedical applications, and customisation of scoliosis braces might lead to greater patient satisfaction and improved compliance. We present here the design of a randomised controlled trial on the clinical effectiveness of 3D-printed braces versus thoracolumbosacral orthoses (TLSO) for patients with AIS.

Methods and analysis

Patients with AIS (age 10–16 years) with Risser sign 0-II, Cobb angle of main curve of 20°−40°, premenarchal or no more than 1-year postmenarchal (for women), and no history of treatment are eligible, unless they are unable to tolerate the treatment or refuse participation. A total of 88 patients will be randomised into either the 3D group or TLSO group on a 1:1 basis. Participants in the 3D group will choose between a 3D-printed brace and TLSO, according to the Zelen’s design of the trial. Primary outcome measures will include the average brace-wear time per day, health-related quality of life and Cobb angle progression of the primary curve. Secondary outcome measures will include immediate in-brace correction of Cobb angle of the primary curve, rate of conversion to surgery and incidence of any adverse events. This study is designed as a single-centre, two-arm, superiority and open-label randomised controlled trial. The sample size is calculated with reference to the preliminary study and based on the sample size calculation formula.

Ethics and dissemination

This study was approved by the Peking University Third Hospital Medicine Science Research Ethics Committee (No: 2019-017-02). Results of the trial will be submitted for publication in a peer-reviewed journal and as conference presentations.

Trial registration number

ChiCTR1900027379, pre-results.
External validation of the improving partial risk adjustment in surgery (PRAIS-2) model for 30-day mortality after paediatric cardiac surgery
Authors: Cocomello Lucia , Caputo Massimo , Cornish Rosie , Lawlor Deborah
Published: November 2020

Objective

Independent temporal external validation of the improving partial risk adjustment in surgery model (PRAIS-2) to predict 30-day mortality in patients undergoing paediatric cardiac surgery.

Design

Retrospective analysis of prospectively collected data.

Setting

Paediatric cardiac surgery.

Intervention

PRAIS-2 validation was carried out using a two temporally different single centre (Bristol, UK) cohorts: Cohort 1 surgery undertaken from April 2004 to March 2009 and Cohort 2 from April 2015 to July 2019. For each subject PRAIS-2 score was calculated according to the original formula.

Participants

A total of 1352 (2004-2009) and 1197 (2015-2019) paediatric cardiac surgical procedures were included in the Cohort 1 and Cohort 2, respectively (median age at the procedure 6.3 and 7.1 months).

Primary and secondary outcome measures

PRAIS-2 performance was assessed in terms of discrimination by means of ROC (receiver operating characteristic) curve analysis and calibration by using the calibration belt method.

Results

PRAIS-2 score showed excellent discrimination for both cohorts (AUC 0.72 (95%CI: 0.65 to 0.80) and 0.88 (95%CI: 0.82 to 0.93), respectively). While PRAIS-2 was only marginally calibrated in Cohort 1, with a tendency to underestimate risk in lowrisk and overestimate risk in high risk procedures (P-value = 0.033), validation in Cohort 2 showed good calibration with the 95% confidence belt containing the bisector for predicted mortality (P-value = 0.143). We also observed good prediction accuracy in the non-elective procedures (N = 483;AUC 0.78 (95%CI 0.68 to 0.87); Calibration belt containing the bisector (P-value=0.589).

Conclusions

In a single centre UK-based cohort, PRAIS-2 showed excellent discrimination and calibration in predicting 30-day mortality in paediatric cardiac surgery including in those undergoing non-elective procedures. Our results support a wider adoption of PRAIS-2 score in the clinical practice.
Study protocol and implementation details for a pragmatic, stepped-wedge cluster randomised trial of a digital adherence technology to facilitate tuberculosis treatment completion
Authors: Crowder Rebecca , Kityamuwesi Alex , Kiwanuka Noah , Lamunu Maureen , Namale Catherine , Tinka Lynn Kunihira , Nakate Agnes Sanyu , Ggita Joseph , Turimumahoro Patricia , Babirye Diana , Oyuku Denis , Berger Christopher Allen , Tucker Austin , Patel Devika , Sammann Amanda , Dowdy David , Stavia Turyahabwe , Cattamanchi Adithya , Katamba Achilles
Published: November 2020

Introduction

Low-cost digital adherence technologies (DATs) such as 99DOTS have emerged as an alternative to directly observed therapy (DOT), the current standard for tuberculosis (TB) treatment supervision. However, there are limited data to support DAT scale-up. The ‘DOT to DAT’ trial aims to evaluate the effectiveness and implementation of a 99DOTS-based TB treatment supervision strategy.

Methods and analysis

This is a pragmatic, stepped-wedge cluster randomised trial, with hybrid type 2 effectiveness-implementation design. The trial will include all adults (estimated N=1890) treated for drug-susceptible pulmonary TB over an 8-month period at 18 TB treatment units in Uganda. Three sites per month will switch from routine care (DOT) to the intervention (99DOTS-based treatment supervision) beginning in month 2, with the order determined randomly. 99DOTS enables patients to be monitored while self-administering TB medicines. Patients receive daily automated short message service (SMS) dosing reminders and confirm dosing by calling toll-free numbers. The primary effectiveness outcome is the proportion of patients completing TB treatment. With 18 clusters randomised into six steps and an average cluster size of 15 patients per month, the study will have 89% power to detect a 10% or greater increase in treatment completion between the routine care and intervention periods. Secondary outcomes include more proximal effectiveness measures as well as quantitative and qualitative assessments of the reach, adoption and implementation of the intervention.

Ethics and dissemination

Ethics approval was granted by institutional review boards at Makerere University School of Public Health and the University of California San Francisco. Findings will be disseminated through peer-reviewed publications, presentations at scientific conferences and presentations to key stakeholders.

Trial registration number

PACTR201808609844917.
Endovascular treatment versus standard medical treatment for acute basilar artery occlusion: protocol for a systematic review and meta-analysis
Authors: Bai Xuesong , Zhang Xiao , Li Long , Wang Tao , Dmytriw Adam Andrew , Feng Yao , Yang Kun , Wang Xue , Ma Yan , Jiao Liqun
Published: November 2020

Introduction

Acute basilar artery occlusion (BAO) can cause posterior circulation stroke. There are two predominant therapies for BAO: standard medical treatment (SMT) and SMT plus endovascular thrombectomy (EVT). However, a conclusive systematic comparison of the safety and efficacy of SMT and those of SMT plus EVT for the treatment of BAO is lacking. Thus, a systematic review and meta-analysis is needed to evaluate the safety and efficacy of SMT and SMT plus EVT for the treatment of BAO.

Methods and analysis

This protocol is drafted referring to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses for Protocols guidelines. We will search eligible studies from four main databases including MEDLINE, Web of Science, Cochrane Library and Embase. Randomised controlled trials (RCTs) and observational studies published before 1 October 2020 will be included. Two reviewers in our team will conduct the study selection and data extraction independently. Risk of bias will be assessed by Cochrane Collaboration criteria and the Newcastle-Ottawa scale for RCTs and observational studies, respectively. We will assess the good functional outcomes defining the modified Rankin scale score ≤2 at 90 days after treatment, short-term stroke severity as National Institutes of Health Stroke Scale score at 24 hours after intervention, and successful recanalisation as a modified Thrombolysis in Cerebral Infarction scale score of ≥2b after intervention. Also, safety outcomes will be assessed. The performance of this meta-analysis will depend on the quantity of included studies. The assessment of study heterogeneity will be performed by the I2 statistic. If there is mild heterogeneity (I2<20%) of intervention outcomes in included studies, the fixed-effect model will be applied; otherwise, the random-effect model will be performed. Subgroup analyses and an assessment of publication bias will also be conducted with sufficient data.

Ethics and dissemination

No collection of primary data from patients is needed. Therefore, the ethical approval is unnecessary. The results may be presented in a peer-reviewed journal and related conferences.

PROSPERO registration number

CRD42020176764.
Mask shortage during epidemics and pandemics: a scoping review of interventions to overcome limited supply
Authors: Kirubarajan Abirami , Khan Shawn , Got Tiffany , Yau Matthew , Bryan Jennifer M , Friedman Steven Marc
Published: November 2020

Objective

To characterise published evidence regarding preclinical and clinical interventions to overcome mask shortages during epidemics and pandemics.

Design

Systematic scoping review.

Settings

All healthcare settings relevant to epidemics and pandemics.

Search strategy

English peer-reviewed studies published from January 1995 to June 2020 were included. Literature was identified using four databases (Medline-OVID, EMBASE, CINAHL, Cochrane Library), forwards-and-backwards searching through Scopus and an extensive grey literature search. Assessment of study eligibility, data extraction and evidence appraisal were performed in duplicate by two independent reviewers.

Results

Of the 11 220 database citations, a total of 47 articles were included. These studies encompassed six broad categories of conservation strategies: decontamination, reusability of disposable masks and/or extended wear, layering, reusable respirators, non-traditional replacements or modifications and stockpiled masks. Promising strategies for mask conservation in the context of pandemics and epidemics include use of stockpiled masks, extended wear of disposable masks and decontamination.

Conclusion

There are promising strategies for overcoming face mask shortages during epidemics and pandemics. Further research specific to practical considerations is required before implementation during the COVID-19 pandemic.
Dementias Platform UK Clinical Studies and Great Minds Register: protocol of a targeted brain health studies recontact database
Authors: Koychev Ivan , Young Simon , Holve Heather , Ben Yehuda Michael , Gallacher John
Published: November 2020

Introduction

The case for de-risking neurodegenerative research and development through highly informative experimental medicine studies early in the disease process is strong. Such studies depend on the availability of genetic as well as high-granularity, longitudinal, phenotypic data in healthy ageing individuals who can be recruited into early phase trials on the basis of their perceived dementia risk. Until now the creation of such research infrastructure has been hampered by the lack of expense and time required to gather the rich longitudinal data needed for adequate risk stratification. Dementias Platform UK (DPUK) is a public–private partnership that brings together data from over 40 cohorts in a standardised framework, which represent an until now unavailable opportunity to create such a resource through a streamlined brain health recontact platform based on existing cohorts, as well as prospectively collected data.

Methods and analysis

The DPUK recontact platform consists of an opt-in (Great Minds, GM) and an opt-out component (Clinical Studies Register, CSR). GM requires invited DPUK cohort participants to consent to targeted recontact at the GM website and then to provide self-reported demographic and medical history information relevant to recruitment into clinical studies. Participants complete prospective browser-based and smartphone-based cognitive tests and are given the option for remote genetic and actigraphy testing. The GM data are linked to the retrospective DPUK cohort dataset, including genotypic and longitudinal phenotypic data. The CSR is a solution for cohorts explicitly allowing targeted recontact. Approved studies provide prescreening criteria on the basis of the CSR/GM dataset, and individuals meeting these criteria are offered participation directly (GM) or through the parent DPUK cohort (CSR). Descriptive statistics will be used to summarise the outcomes relevant to the number of participants engaged with the register. Its sample size is not defined but is limited by the size of the DPUK parent cohorts.

Ethics and dissemination

The database was approved by the South Central–Oxford C Research Ethics Committee, reference 18/SC/0268 on the 27th of June 2018 and amended on the 1st of November 2019. The availability of the register to researchers will be disseminated through DPUK’s official communication channels as well as national and international scientific meetings.
Mapping the current knowledge in syndemic research applied to men who have sex with men: a scoping review protocol
Authors: Ouafik Maxence , Buret Laetitia , Belche Jean-Luc , Scholtes Beatrice
Published: November 2020

Introduction

Men who have sex with men (MSM) are disproportionally affected by a number of health conditions that are associated with violence, stigma, discrimination, poverty, unemployment or poor healthcare access. In recent years, syndemic theory provided a framework to explore the interactions of these health disparities on the biological and social levels. Research in this field has been increasing for the past 10 years, but methodologies have evolved and sometimes differed from the original concept. The aim of this paper is to provide an overview of the existing literature on syndemic theory applied to MSM in order to identify knowledge gaps, inform future investigations and expand our understanding of the complex interactions between avoidable health conditions in a vulnerable population.

Methods and analysis

The proposed scoping review will follow the methodological framework developed by Arksey and O’Malley with subsequent enhancements by Levac et al, Colquhoun et al and Peters et al as well as the Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for scoping review. A systematic search of MEDLINE, PsycInfo, Scopus, Cochrane Central Register of Controlled Trials and ProQuest Sociological Abstracts will be conducted. Reference lists of the included studies will be hand-searched for additional studies. Screening and data charting will be achieved using DistillerSR. Data collating, summarising and reporting will be performed using R and RStudio. Tabular and graphical summaries will be presented, alongside an evidence map and a descriptive overview of the main results.

Ethics and dissemination

This scoping review does not require ethical approval. Data and code will be made accessible after manuscript submission. Final results will be disseminated through publication in a peer-reviewed journal and collaboration with grassroots Lesbian, Gay, Bisexual, Transgender, Queer, Intersex and Asexual (LGBTQIA+) organisations.

Registration

This protocol was registered on manuscript submission on the Open Science Framework at the following address: https://osf.io/jwxtd; DOI: 10.17605/OSF.IO/JWXTD.
Risk factors for non-communicable diseases in Bangladesh: findings of the population-based cross-sectional national survey 2018
Authors: Riaz Baizid Khoorshid , Islam Md Ziaul , Islam A N M Shamsul , Zaman M M , Hossain Md Akram , Rahman Md Mujibur , Khanam Fahmida , Amin K M Bayzid , Noor Irfan Nowroze
Published: November 2020

Objectives

To determine the national prevalence of risk factors of non-communicable diseases (NCD) in the adult population of Bangladesh.

Design

The study was a population-based national cross-sectional study.

Setting

This study used 496 primary sampling units (PSUs) developed by the Bangladesh Bureau of Statistics. The PSUs were equally allocated to each division and urban and rural stratum within each division.

Participants

The participants were adults aged 18 to 69 years, who were usual residents of the households for at least 6 months and stayed the night before the survey. Out of 9900 participants, 8185 (82.7%) completed STEP-1 and STEP-2, and 7208 took part in STEP-3.

Primary and secondary outcome

The prevalence of behavioural, physical and biochemical risk factors of NCD. Data were weighted to generate national estimates.

Results

Tobacco use was significantly (p<0.05) higher in the rural (45.2%) than the urban (38.8%) population. Inadequate fruit/vegetable intake was significantly (p<0.05) higher in the urban (92.1%) than in the rural (88.9%) population. The mean salt intake per day was higher in the rural (9.0 g) than urban (8.9 g) population. Among all, 3.0% had no, 70.9% had 1 to 2 and 26.2% had ≥3 NCD risk factors. The urban population was more likely to have insufficient physical activity (adjusted OR (AOR): 1.2, 95% CI: 1.2 to 1.2), obesity (AOR: 1.5, 95% CI: 1.5 to 1.5), hypertension (AOR: 1.3, 95% CI: 1.3 to 1.3), diabetes (AOR: 1.6, 95% CI: 1.6 to 1.6) and hyperglycaemia (AOR: 1.1, 95% CI: 1.1 to 1.1).

Conclusions

Considering the high prevalence of the behavioural, physical and biochemical risk factors, diverse population and high-risk group targeted interventions are essential to combat the rising burden of NCDs.
Clinical evaluation of pharmacists’ interventions on multidisciplinary lung transplant outpatients’ management: results of a 7-year observational study
Authors: Duwez Marion , Chanoine Sébastien , Lepelley Marion , Vo Thi Ha , Pluchart Hélène , Mazet Roseline , Allenet Benoit , Pison Christophe , Briault Amandine , Saint-Raymond Christelle , Camara Boubou , Claustre Johanna , Bedouch Pierrick
Published: November 2020

Objectives

Lung transplant (LT) recipients require multidisciplinary care because of the complexity of therapeutic management. Pharmacists are able to detect drug-related problems and provide recommendations to physicians through pharmacists’ interventions (PIs). We aimed at assessing the clinical impact of PIs on therapeutic management in LT outpatients.

Design

Data were collected prospectively from an LT recipients cohort during 7 years. A multidisciplinary committee assessed retrospectively the clinical impact of accepted PIs.

Setting

French University Hospital.

Participants

LT outpatients followed from 2009 to 2015.

Primary outcome measures

Clinical impact of PIs performed by pharmacists using the CLEO tool and the Pareto chart.

Results

1449 PIs led to a change in patient therapeutic management and were mainly related to wrong dosage (39.6%) and untreated indication (19.6%). The clinical impact of PIs was ‘avoids fatality’, ‘major’ and ‘moderate’, in 0.1%, 7.0% and 57.9%, respectively. Immunosuppressants, antimycotics for systemic use and antithrombotic agents had the greatest clinical impact according to the Pareto chart. PIs related to drug–drug interactions (10%) mainly had a moderate and major clinical impact (82.3%, p<0.0001).

Conclusion

Clinical pharmacists play a key role for detecting drug-related problems mostly leading to a change in therapeutic management among LT outpatients. Our study provides a new insight to analyse the clinical impact of PIs in order to target PIs which have most value and contribute to patient care through interdisciplinary approach.
Regional differences in the patient population of general practices in northern Germany: results of a mixed-methods study
Authors: Hansen Heike , Schäfer Ingmar , Pohontsch Nadine Janis , Kazek Agata , Hardt Hanna , Lühmann Dagmar , Scherer Martin
Published: November 2020

Objectives

The aim of our study was to explore patient types in general practitioner (GP) practices and to quantify the regional differences of the frequencies of these patient types in northern Germany.

Design and setting

We conducted a mixed-methods study based on focus groups and standardised interviews with GPs. All counties and independent cities within a radius of 120 km around Hamburg were assigned one of three regional categories (urban areas, environs, rural areas). The focus groups were analysed using qualitative content analysis. Relative frequencies of consultations by patient types and differences between the regions were calculated. Logistic regression analyses were used to identify differences among regions.

Participants

Nine focus groups with 65 GPs (67.7% male). From the 280 initially recruited GPs 211 (65.4% male) could be personally interviewed.

Results

Four themes with 27 patient types were derived from the focus groups: patients classified by morbidity, sociodemographic characteristics, special care needs and patient behaviour. Five patient characteristics were significantly more prevalent in urban areas than rural areas: patients with migration background and culturally different disease concepts (OR 1.23; 95% CI 1.06 to 1.42), privately insured patients (OR 1.17; 95% CI 1.05 to 1.31), educationally disadvantaged patients with low health literacy (OR 1.11; 95% CI 1.04 to 1.19), patients with psychiatric disorders (OR 1.07; 95% CI 1.02 to 1.12) and senior citizens living on their own without caregivers (OR 1.05; 95% CI 1.05 to 1.31). Three patient types were significantly less prevalent in urban areas: minors accompanied by their parents (OR 0.71; 95% CI 0.61 to 0.83), patients with poor therapy adherence (OR 0.87, 95% CI 0.80 to 0.95) and patients with dementia (OR 0.90; 95% CI 0.82 to 0.99).

Conclusions

GPs could compensate the specific needs of their patients with medical training aligned with the requirements of their region. Urban GPs need skills treating patients with psychiatric, social and cultural problems, rural GPs regarding the care for children or noncompliant patients.

Trial registration number

NCT02558322
Indicators and correlates of low energy availability in male and female dancers
Authors: Keay Nicola , Overseas AusDancers , Francis Gavin
Published: November 2020

Objectives

To investigate indicators and correlates of low energy availability (LEA) in male and female dancers.

Methods

A Dance-Specific Energy Availability Questionnaire (DEAQ) was developed and administered online internationally to dancers training at preprofessional, professional or advanced amateur level. The DEAQ drew on current validated, published questionnaires for LEA, linked to the clinical outcomes of relative energy deficiency in sport (RED-S). Questions addressed recognised physiological indicators and consequences of LEA in the context of dance, together with potential correlates. LEA was quantified using a scoring system to include these characteristics.

Results

247 responses to the DEAQ were analysed (225 female and 22 male), mean age 20.7 years (SD 7.9) with 85% practising ballet. Psychological, physiological and physical characteristics consistent with LEA were reported by 57% of the female dancers and 29% of male dancers, indicating a risk of RED-S. The unique nature of dance training, in terms of demands and environment, was found to be potentially influential in development of this situation. Less than one-third (29%) of dancers were aware of RED-S.

Conclusion

This study found dancers to be a specific group of high-level artistic performers displaying indicators of LEA and consequently at risk of developing the adverse clinical health and performance consequences of RED-S. Awareness of RED-S was low. The DEAQ has the potential to raise awareness and be a practical, objective screening tool to identify dancers in LEA, at risk of developing RED-S.
Efficacy and safety of pharmacological cachexia interventions: systematic review and network meta-analysis
Authors: Saeteaw Manit , Sanguanboonyaphong Phitjira , Yoodee Jukapun , Craft Kaitlyn , Sawangjit Ratree , Ngamphaiboon Nuttapong , Shantavasinkul Prapimporn Chattranukulchai , Subongkot Suphat , Chaiyakunapruk Nathorn
Published: November 2020

Aims

Randomised controlled trials (RCTs) demonstrated benefits of pharmacological interventions for cachexia in improving weight and appetite. However, comparative efficacy and safety are not available. We conducted a systematic review and network meta-analysis (NMA) to evaluate the relative efficacy and safety of pharmacological interventions for cachexia.

Methods

PubMed, EmBase, Cochrane, and ClinicalTrials.gov were searched for RCTs until October 2019. Key outcomes were total body weight (TBW) improvement, appetite (APP) score and serious adverse events. Two reviewers independently extracted data and assessed risk of bias. NMA was performed to estimate weight gain and APP score increase at 8 weeks, presented as mean difference (MD) or standardised MD with 95% CI.

Results

80 RCTs (10 579 patients) with 12 treatments were included. Majority is patients with cancer (7220). Compared with placebo, corticosteroids, high-dose megestrol acetate combination (Megace_H_Com) (≥400 mg/day), medroxyprogesterone, high-dose megestrol acetate (Megace_H) (≥400 mg/day), ghrelin mimetic and androgen analogues (Androgen) were significantly associated with MD of TBW of 6.45 (95% CI 2.45 to 10.45), 4.29 (95% CI 2.23 to 6.35), 3.18 (95% CI 0.94 to 5.41), 2.66 (95% CI 1.47 to 3.85), 1.73 (95% CI 0.27 to 3.20) and 1.50 (95% CI 0.56 to 2.44) kg. For appetite improvement, Megace_H_Com, Megace_H and Androgen significantly improved standardised APP score, compared with placebo. There is no significant difference in serious adverse events from all interventions compared with placebo.

Conclusions

Our findings suggest that several pharmacological interventions have potential to offer benefits in treatment of cachexia especially Megace_H and short-term use corticosteroids. Nonetheless, high-quality comparative studies to compare safety and efficacy are warranted for better management of cachexia.
Sleep softly: Schubert, ethics and the value of dying well
Authors: Wilkinson Dominic
Published: November 2020

Ethical discussions about medical treatment for seriously ill babies or children often focus on the ‘value of life’ or on ‘quality of life’ and what that might mean. In this paper, I look at the other side of the coin—on the value of death, and on the quality of dying. In particular, I examine whether there is such a thing as a good way to die, for an infant or an adult, and what that means for medical care. To do that, I call on philosophy and on personal experience. However, I will also make reference to art, poetry and music. That is partly because the topic of mortality has long been reflected on by artists as well as philosophers and ethicists. It is also because, as we will see, there may be some useful parallels to draw.
Experimental and theoretical investigations on fin configuration effects of dynamically installed anchors in clay
Authors: Fu Yong , Liu Yong
Published: November 2020

Dynamically installed anchor (DIA) for deepwater mooring is an innovative and cost-effective technology in offshore foundation engineering; however, research on the effects of fin configuration of DIAs is limited. This study therefore systematically examines the effects of fin length–width ratio, fin surface area, fin position, and fin shape on the embedment depth and time-dependent holding capacity of DIAs by experimental and theoretical approaches. First, a series of centrifuge tests was performed on four DIA models with an identical fin surface area, but different fin configurations. It is found that the DIA model with short-wide-rectangular fins that are installed at the rear of the shaft achieves deeper embedment depth and higher holding capacity; whereas, the rectangular- and elliptical-shaped DIA models are similar in terms of embedment and capacity. This motivates the proposal for another nine types of finned DIAs in a more systematic manner. Furthermore, the performance of embedment depth and time-dependent holding capacity for these nine DIAs was theoretically assessed using the well-established theoretical methods. In this study, two scenarios with identical impact velocity or embedment depth were examined; wherein the variation of holding capacity with reconsolidation time was explicitly accounted for. Based on the findings, practical implications of fin configurations were reached that may benefit the design of finned DIAs in practice.
The geometrical origin of dark energy
Authors: Faraggi Alon E. , Matone Marco
Published: November 2020

The geometrical formulation of the quantum Hamilton–Jacobi theory shows that the quantum potential is never trivial, so that it plays the rôle of intrinsic energy. Such a key property selects the Wheeler–DeWitt (WDW) quantum potential $$Q[g_{jk}]$$

Q
[

g

jk

]

as the natural candidate for the dark energy. This leads to the WDW Hamilton–Jacobi equation with a vanishing kinetic term, and with the identification $$\begin{aligned} \Lambda =-\frac{\kappa ^2}{\sqrt{{\bar{g}}}}Q[g_{jk}]. \end{aligned}$$

Λ
=
-

κ
2

g

¯

Q

[

g

jk

]

.

This shows that the cosmological constant is a quantum correction of the Einstein tensor, reminiscent of the von Weizsäcker correction to the kinetic term of the Thomas–Fermi theory. The quantum potential also defines the Madelung pressure tensor. The geometrical origin of the vacuum energy density, a strictly non-perturbative phenomenon, provides strong evidence that it is due to a graviton condensate. Time independence of the regularized WDW equation suggests that the ratio between the Planck length and the Hubble radius may be a time constant, providing an infrared/ultraviolet duality. We speculate that such a duality is related to the local to global geometry theorems for constant curvatures, showing that understanding the universe geometry is crucial for a formulation of Quantum Gravity.
The Yamada Model for a Self-Pulsing Laser: Bifurcation Structure for Nonidentical Decay Times of Gain and Absorber
Authors: Otupiri Robert , Krauskopf Bernd , Broderick Neil G. R.
Published: November 2020

We consider self-pulsing in lasers with a gain section and an absorber section via a mechanism known as [Formula: see text]-switching, as described mathematically by the Yamada ordinary differential equation model for the gain, the absorber and the laser intensity. More specifically, we are interested in the case that gain and absorber decay on different time-scales. We present an overall bifurcation structure by showing how the two-parameter bifurcation diagram in the plane of pump strength versus decay rate of the gain changes with the ratio between the two decay rates. In total, there are ten cases BI to BX of qualitatively different two-parameter bifurcation diagrams, which we present with an explanation of the transitions between them. Moroever, we show for each of the associated eleven cases of structurally stable phase portraits (in open regions of the parameter space) a three-dimensional representation of the organization of phase space by the two-dimensional manifolds of saddle equilibria and saddle periodic orbits.

The overall bifurcation structure provides a comprehensive picture of the observable dynamics, including multistability and excitability, which we expect to be of relevance for experimental work on [Formula: see text]-switching lasers with different kinds of saturable absorbers.
Milnor and Topological Attractors in a Family of Two-Dimensional Lotka–Volterra Maps
Authors: Gardini Laura , Tikjha Wirot
Published: November 2020

In this work, we consider a family of Lotka–Volterra maps [Formula: see text] for [Formula: see text] and [Formula: see text] which unfold a map originally proposed by Sharkosky for [Formula: see text] and [Formula: see text]. Multistability is observed, and attractors may exist not only in the positive quadrant of the plane, but also in the region [Formula: see text]. Some properties and bifurcations are described. The [Formula: see text]-axis is invariant, on which the map reduces to the logistic. For any [Formula: see text] an interval of values for [Formula: see text] exists for which all the cycles on the [Formula: see text]-axis are transversely attracting. This invariant set is the source of several kinds of bifurcations. Riddling bifurcations lead to attractors in Milnor sense, not topological but with a stable set of positive measure, which may be the unique attracting set, or coexisting with other topological attractors. The riddling and blowout bifurcations are described related to chaotic intervals on the invariant set, and these global bifurcations have different dynamic results. Chaotic intervals which are not topological attractors may have all the cycles transversely attracting and as Milnor attractors. We show that Milnor attractors may also be related to attracting cycles on the [Formula: see text]-axis at the bifurcation associated with the transverse and parallel eigenvalues. We show particular examples related to topological attractors with very narrow basins of attraction, when the majority of the trajectories are divergent.
A Phasor Analysis Method for Charge-Controlled Memory Elements
Authors: Guo Zhang , Iu Herbert H. C. , Si Gangquan , Xu Xiang , Oresanya Babajide Oluwatosin , Bie Yiyuan
Published: November 2020

Memory elements, including memristor, memcapacitor, meminductor and second-order memristor, have been widely exploited recently to realize circuit systems for a broad scope of applications. This paper introduces a phasor analysis method for memory elements to help with the understanding of the complex nonlinear phenomena in circuits with memory elements. With the proposed method, all different memory elements could be described in a unified form and the series-connected circuit with memristor, memcapacitor, meminductor and second-order memristor could be simply modeled as one variable [Formula: see text]. Thus, the phasor vectors provided a way to conveniently calculate the [Formula: see text]–[Formula: see text] relation of different memory elements and to clearly understand the similarities and differences between all memory elements. Then some interesting phenomena were introduced when combining different memory elements. Moreover, a specific [Formula: see text] with certain [Formula: see text]–[Formula: see text] relations could be easily obtained with the method. And through the inverse calculation, the specific [Formula: see text] could be decomposed to a certain combination of memory elements. Meanwhile, the parameters of [Formula: see text] in the phasor domain were analyzed. Furthermore, the frequency characteristic for a [Formula: see text] circuit could be easily analyzed with the method and a particular series resonance was introduced.
Hidden Attractors with Conditional Symmetry
Authors: Li Chunbiao , Sun Jiayu , Sprott Julien Clinton , Lei Tengfei
Published: November 2020

By introducing an absolute value function for polarity balance, some new examples of chaotic systems with conditional symmetry are constructed that have hidden attractors. Coexisting oscillations along with bifurcations are investigated by numerical simulation and circuit implementation. Such new cases enrich the gallery of hidden chaotic attractors of conditional symmetry that are potentially useful in engineering technology.
Nonlinear Behavior of a Novel Switching Jerk System
Authors: Hosham Hany A.
Published: November 2020

This paper proposes a novel chaotic jerk system, which is defined on four domains, separated by codimension-2 discontinuity surfaces. The dynamics of the proposed system are conveniently described and analyzed through a generalization of the Poincaré map which is constructed via an explicit solution of each subsystem. This provides an approach to formulate a robust bifurcation problem as a nonlinear inhomogeneous eigenvalue problem. Also, we establish some criteria for the existence of a period-doubling bifurcation and discuss some of the interesting categories of complex behavior such as multiple period-doubling bifurcations and chaotic behavior when the trajectory undergoes a segment of sliding motion. Our results emphasize that the sharp switches in the behavior are mainly responsible for generating new and unique qualitative behavior of a simple linear system as compared to the nonlinear continuous system.
Nonlinear Oscillations of Nonlinear Damping Gyros: Resonances, Hysteresis and Multistability
Authors: Miwadinou C. H. , Monwanou A. V. , Hinvi L. A. , Tamba V. Kamdoum , Koukpémèdji A. A. , Chabi Orou J. B.
Published: November 2020

This paper addresses the issues on the dynamics of nonlinear damping gyros subjected to a quintic nonlinear parametric excitation. The fixed points and their stability are analyzed for the autonomous gyros equation. The number of fixed points of the system varies from one to six. The approximate equation of gyros is considered by expanding the nonlinear restoring force and parametric excitation for the study of the dynamics of gyros. Amplitude and frequency of possible resonances are found by using the multiple scales method. Also obtained are the principal parametric resonance and orders 4 and 6 subharmonic resonances. The stability conditions for each of these resonances are also obtained. Chaotic oscillations, multistability, hysteresis, and coexisting attractors are found using the bifurcation diagrams, the Lyapunov exponents, the phase portraits, the Poincaré section and the time histories. The effects of the damping parameter, the angular spin velocity and the parametric nonlinear excitation are analyzed. Results obtained by using the approximate gyros equation are compared to the dynamics obtained with the exact equation of gyros. The analytical investigations are complemented by numerical simulations.
Stability and Bifurcation Analysis in a Nonlinear Harvested Predator–Prey Model with Simplified Holling Type IV Functional Response
Authors: Shang Zuchong , Qiao Yuanhua , Duan Lijuan , Miao Jun
Published: November 2020

In this paper, a type of predator–prey model with simplified Holling type IV functional response is improved by adding the nonlinear Michaelis–Menten type prey harvesting to explore the dynamics of the predator–prey system. Firstly, the conditions for the existence of different equilibria are analyzed, and the stability of possible equilibria is investigated to predict the final state of the system. Secondly, bifurcation behaviors of this system are explored, and it is found that saddle-node and transcritical bifurcations occur on the condition of some parameter values using Sotomayor’s theorem; the first Lyapunov constant is computed to determine the stability of the bifurcated limit cycle of Hopf bifurcation; repelling and attracting Bogdanov–Takens bifurcation of codimension 2 is explored by calculating the universal unfolding near the cusp based on two-parameter bifurcation analysis theorem, and hence there are different parameter values for which the model has a limit cycle, or a homoclinic loop; it is also predicted that the heteroclinic bifurcation may occur as the parameter values vary by analyzing the isoclinic of the improved system. Finally, numerical simulations are done to verify the theoretical analysis.
The Structural Stability of Maps with Heteroclinic Repellers
Authors: Chen Yuanlong , Li Liangliang , Wu Xiaoying , Wang Feng
Published: November 2020

This note is concerned with the effect of small [Formula: see text] perturbations on a discrete dynamical system [Formula: see text], which has heteroclinic repellers. The question to be addressed is whether such perturbed system [Formula: see text] has heteroclinic repellers. It will be shown that if [Formula: see text] is small enough, [Formula: see text] has heteroclinic repellers, which implies that it is chaotic in the sense of Devaney. In addition, if [Formula: see text] and [Formula: see text] has regular nondegenerate heteroclinic repellers, then [Formula: see text] has regular nondegenerate heteroclinic repellers, where [Formula: see text] is a small Lipschitz perturbation of [Formula: see text]. Three examples are presented to validate the theoretical conclusions.
Chaos Generated by a Class of 3D Three-Zone Piecewise Affine Systems with Coexisting Singular Cycles
Authors: Lu Kai , Xu Wenjing , Yang Qigui
Published: November 2020

It is a significant and challenging task to detect both the coexistence of singular cycles, mainly homoclinic and heteroclinic cycles, and chaos induced by the coexistence in nonsmooth systems. By analyzing the dynamical behaviors on manifolds, this paper proposes some criteria to accurately locate the coexistence of homoclinic cycles and of heteroclinic cycles in a class of three-dimensional (3D) piecewise affine systems (PASs), respectively. It further establishes the existence conditions of chaos arising from such coexistence, and presents a mathematical proof by analyzing the constructed Poincaré map. Finally, the simulations for two numerical examples are provided to validate the established results.
Impact of the Fear Effect on the Stability and Bifurcation of a Leslie–Gower Predator–Prey Model
Authors: Wang Xiaoqin , Tan Yiping , Cai Yongli , Wang Weiming
Published: November 2020

In this paper, we investigate analytically and numerically the dynamics of a modified Leslie–Gower predator–prey model which is characterized by the reduction of prey growth rate due to the anti-predator behavior. We prove the existence and local/global stability of equilibria of the model, and verify the existence of Hopf bifurcation. In addition, we focus on the influence of the fear effect on the population dynamics of the model and find that the fear effect can not only reduce the population density of both predator and prey, but also destabilize the coexistence equilibrium, which are beneficial to the occurrence of limit-cycle-induced oscillation, or prevent the occurrence of limit cycle oscillation and increase the stability of the system.