bluuebunny/crossref_metadata_2025_split huggingface dataset:
Spectral Numerical Study of Entropy Generation in Magneto-Convective Viscoelastic Biofluid Flow Through Poro-Elastic Media With Thermal Radiation and Buoyancy Effects
Authors: Mallikarjuna B. , Srinivas J. , Krishna G. Gopi , Bég O. Anwar , Kadir Ali 
Published: April 2021

Abstract
Electromagnetic high-temperature therapy is popular in medical engineering treatments for various diseases including tissue damage ablation repair, hyperthermia, and oncological illness diagnosis. The simulation of transport phenomena in such applications requires multi-physical models featuring magnetohydrodynamics, biorheology, heat transfer, and deformable porous media. Motivated by investigating the fluid dynamics and thermodynamic optimization of such processes, in the present article, a mathematical model is developed to study the combined influence of thermal buoyancy, magnetic field and thermal radiation on the entropy generation, and momentum and heat transfer characteristics in electrically conducting viscoelastic biofluid flow through a vertical deformable porous medium. It is assumed that heat is generated within the fluid by both viscous and Darcy (porous matrix) dissipations. The governing equations for fluid velocity, solid displacement, and temperature are formulated. The boundary value problem is normalized with appropriate transformations. The nondimensional biofluid velocity, solid displacement, and temperature equations with appropriate boundary conditions are solved computationally using a spectral method. Verification of accuracy is conducted via monitoring residuals of the solutions. The effects of various parameters on flow velocity, solid displacement, temperature, and entropy generation are depicted graphically and discussed. Increasing magnetic field and drag parameters are found to reduce the field velocity, solid displacement, temperature, and entropy production. Entropy production is enhanced with an increase in buoyancy parameter and volume fraction of the fluid. The novelty of the work is the simultaneous inclusion of multiple thermophysical phenomena, and the consideration of thermodynamic optimization in coupled thermal/fluid/elastic media. The computations provide an insight into multiphysical transport in electromagnetic radiative tissue ablation therapy and a good benchmark for more advanced simulations.
Computational Model of Predicting Thermal Performance of a Clothed Human by Considering the Clothing Pumping Effect
Authors: Yi Teng , Jiao Jiao , Ruomei Wang , Yi Li 
Published: April 2021

AbstractIn order to predict the functional performance of thermal-functional-designed clothing, the computer simulation method is adopted to investigate the thermoregulation of a clothed human. The primary aim of this study is to develop a computational model which can simulate the thermal physiological indicators and pumping effect simultaneously, while the previous models can only simulate the human thermal physiological performance or clothing pumping effect particularly. The secondary aim is to compare the simulation results predicted by the optimized model, either considering the pumping effect or not, with the results in a physiological experiment conducted by human participants in terms of different thermal responses, including core temperatures and mean skin temperature. A computational model was established to predict the thermal performance of a clothed human by considering the clothing pumping effect in the human-clothing-environment (HCE) system. In addition, the validation of the developed computational model has been investigated by comparing the predicted results of simulation (with or without pumping effect) with the experimental results on human participants, which demonstrates that the clothing pumping effect must be considered during the simulation process due to its vital influence on thermoregulation of a live clothed human. The results from the simulation and the human experiment showed that the pumping effect could dissipate the heat from the body to outside environment, affected the skin temperature, and consequently delayed the increasing of core temperature, especially during the running process.
An Integrated Computational Materials Engineering Predictive Platform for Fatigue Prediction and Qualification of Metallic Parts Built With Additive Manufacturing
Authors: Jalalahmadi B. , Liu J. , Liu Z. , Vechart A. , Weinzapfel N. 
Published: April 2021

Abstract
Additive manufacturing (AM) processes create material directly into a functional shape. Often the material properties vary with part geometry, orientation, and build layout. Today, trial-and-error methods are used to generate material property data under controlled conditions that may not map to the entire range of geometries over a part. Described here is the development of a modeling tool enabling prediction of the performance of parts built with AM, with rigorous consideration of the microstructural properties governing the nucleation and propagation of fatigue cracks. This tool, called DigitalClone® for additive manufacturing (DCAM), is an Integrated Computational Materials Engineering (ICME) tool that includes models of crack initiation and damage progression with the high-fidelity process and microstructure modeling approaches. The predictive model has three main modules: process modeling, microstructure modeling, and fatigue modeling. In this paper, a detailed description and theoretical basis of each module is provided. Experimental validations (microstructure, porosity, and fatigue) of the tool using multiple material characterization and experimental coupon testing for five different AM materials are discussed. The physics-based computational modeling encompassed within DCAM provides an efficient capability to fully explore the design space across geometries and materials, leading to components that represent the optimal combination of performance, reliability, and durability.
Deposition of Fuel Impurities Within Thermal Barrier Coatings in Gas Turbine Hot Gas Paths
Authors: Holländer Christian , Stamm Werner , Lüsebrink Oliver , Harders Harald , Singheiser Lorenz 
Published: April 2021

Abstract
For the reliable operation of modern gas turbines, thermal barrier coatings (TBCs) need to withstand a wide range of ambient conditions resulting from impurities in inlet air or fuels. When analyzing the deposition of detrimental hot gas constituents, previous efforts largely focus on the investigation of solid and molten deposit interaction with TBCs. Recent literature and observations in gas turbines indicate that not only liquids can penetrate porous TBCs, but the deposition from gas phase inside of pores and cracks is also an aspect of TBC degradation. To investigate this vapor deposition process, a diffusion model has been coupled with a thermodynamic equilibrium solver. The diffusion model calculates vapor transport of trace elements through pores and gaps in the TBC, where the thermodynamic equilibrium solver calculates local thermodynamic equilibria to predict whether deposition takes place. In this work, the model is applied to discuss the deposition properties of calcium. In recent literature, calcium has—in some cases—been reported to deposit inside of TBCs as pure anhydrite (CaSO4). An actual anhydrite finding in the TBC of a stationary gas turbine blade was reproduced applying the introduced model. The vapor deposition is shown to occur within and on top of the TBC, depending on several factors, such as pressure, temperatures, calcium-to-silicon ratio, and calcium-to-sulfur ratio. The successful alignment of conditions in real engines with model results will allow addressing the increasing demand for more fuel- and operational flexibility of current and future gas turbines.
The Effectiveness of a 30-Week Concurrent Strength and Endurance Training Program in Preparation for an Ultra-Endurance Handcycling Challenge: A Case Study
Authors: Nevin Jonpaul , Smith Paul 
Published: April 2021

Purpose: The aim of the following case study was to evaluate the effectiveness of a 30-week concurrent strength and endurance training program designed to prepare a trained H4 male handcyclist (aged 28 y, bilateral, above knee amputee, and body mass 65.6 kg) for a 1407-km ultra-endurance handcycling challenge. Methods: This observational case study tracked selected physiological measures, training intensity distribution, and total training load over the course of a 30-week concurrent training protocol. Furthermore, the athlete’s performance profile during the ultra-endurance challenge was monitored with power output, cadence, speed, and heart rate recorded throughout. Results: Findings revealed considerable improvements in power output at a fixed blood lactate concentration of 4 mmol·L−1 (+25.7%), peak aerobic power output (+18.9%), power-to-mass ratio (+18.3%), relative peak oxygen uptake (+13.9%), gross mechanical efficiency (+4.6%), bench press 1-repetition maximum (+4.3%), and prone bench pull 1-repetition maximum (+14.9%). The athlete completed the 1407-km route in a new handcycling world record time of 89:55 hours. Average speed was 18.7 (2.1) km·h−1; cadence averaged 70.0 (2.6) rpm, while average power output was 67 (12) W. In terms of internal load, the athlete’s average heart rate was 111 (11) beats per minute. Conclusion: These findings demonstrate how a long-term concurrent strength and endurance training program can be used to optimize handcycling performance capabilities in preparation for an ultra-endurance cycling event. Knowledge emerging from this case study provides valuable information that can guide best practices with respect to handcycling training for ultra-endurance events.
Comparison of the efficacy and safety of cuffed versus uncuffed endotracheal tubes for infants in the intensive care setting: a pilot, unblinded RCT
Authors: Thomas Rebecca E , Erickson Simon , Hullett Bruce , Minutillo Corrado , Lethbridge Martyn , Vijayasekaran Shyan , Agrawal Sachin , Bulsara Max K , Rao Shripada C 
Published: April 2021

ObjectiveTo study effectiveness and safety of cuffed versus uncuffed endotracheal tubes (ETTs) in small infants in the intensive care unit (ICU).DesignPilot RCT.SettingNeonatal and paediatric ICUs of children’s hospital in Western Australia.ParticipantsSeventy-six infants ≥35 weeks gestation and infants <3 months of age, ≥3 kg.InterventionsPatients randomly assigned to Microcuff cuffed or Portex uncuffed ETT.Main outcomes measuresPrimary outcome was achievement of optimal ETT leak in target range (10%–20%). Secondary outcomes included: reintubations, ventilatory parameters, ventilatory complications, postextubation complications and long-term follow-up.ResultsSuccess rate (achievement of mean leak in the range 10%–20%) was 13/42 (30.9%) in the cuffed ETT group and 6/34 (17.6%) in uncuffed ETT group (OR=2.09; 95% CI (0.71 to 6.08); p=0.28). Mean percentage time within target leak range in cuffed ETT group 28% (IQR: 9–42) versus 15% (IQR: 0–28) in uncuffed ETT group (p=0.01). There were less reintubations to optimise size in cuffed ETT group 0/40 versus 10/36 (p<0.001). No differences were found in gaseous exchange, ventilator parameters or postextubation complications. There were fewer episodes of atelectasis in cuffed ETT group 0/42 versus 4/34 (p=0.03). No patient had been diagnosed with subglottic stenosis at long-term follow-up.ConclusionsThere was no difference in the primary outcome, though percentage time spent in optimal leak range was significantly higher in cuffed ETT group. Cuffed ETTs reduced reintubations to optimise ETT size and episodes of atelectasis. Cuffed ETTs may be a feasible alternative to uncuffed ETTs in this group of patients.Trial registration numberACTRN12615000081516.
Beyond HIV prevalence: identifying people living with HIV within underserved areas in South Africa
Authors: Kim Hana , Tanser Frank , Tomita Andrew , Vandormael Alain , Cuadros Diego F 
Published: April 2021

IntroductionDespite progress towards the Joint United Nations Programme on HIV/AIDS 95-95-95 targets, South Africa is still suffering from one of the largest HIV epidemics globally. In this study, we generated high-resolution HIV prevalence maps and identified people living with HIV (PLHIV) in underserved areas to provide essential information for the optimal allocation of HIV-related services.MethodsThe data come from the South Africa Demographic and Health Survey conducted in 2016 and spatial variables from other published literature. We produced high-resolution maps of HIV prevalence and underserved areas, defined as a greater than 30 min travel time to the nearest healthcare facility. Using these maps and the population density, we mapped PLHIV and the PLHIV within underserved areas for 30, 60 and 120 min thresholds.ResultsThere was substantial geographic variation in HIV prevalence, ranging from 1.4% to 24.2%, with a median of 11.5% for men, and from 2.1% to 48.1%, with a median of 20.6% for women. Gauteng province showed the highest density for both HIV prevalence and PLHIV. 80% of all areas in the country were identified as underserved areas (30 min threshold), which contained more than 16% and 20% of the total men and women living with HIV, respectively. KwaZulu-Natal province had the largest number of PLHIV in underserved areas (30 min threshold) and showed less than one healthcare facility per 1000 PLHIV.ConclusionOur study showed extensive spatial variation of HIV prevalence and significant numbers of PLHIV in underserved areas in South Africa. Moreover, we identified locations where HIV-related services need to be intensified to reach the ~1.5 million PLHIV in underserved areas, particularly in KwaZulu-Natal province, with less than one healthcare facility per 1000 PLHIV.
Age at entry to UK military service and long-term mental health
Authors: Bergman Beverly P , Mackay DF , Fear NT , Pell JP 
Published: April 2021

IntroductionIt has been suggested that ‘junior entry’ to the UK Armed Forces (prior to age 17.5 years) increases the risk of adverse mental health outcomes. We used data from a large cohort of veterans to examine long-term mental health outcomes in veterans by age at entry to the UK Armed Forces, compared with non-veterans.MethodsRetrospective cohort study of 78 157 veterans in Scotland, born between 1945 and 1995 and and 252 637 matched non-veterans, with up to 37 years follow-up, using Cox proportional hazard models to examine the association between veteran status and cumulative risk of major mental health disorder, stratified by birth cohort, and age at recruitment for the veterans.ResultsThe risk of mental health disorder in the veterans increased with age at entry, ranging from HR 1.12, 95% CI 1.06 to 1.18, p<0.001 for junior entrants to HR 1.37, 95% CI 1.27 to 1.80, p<0.001 for those aged 20–25 years at entry. The pattern was most marked for veterans born before 1960, and age at recruitment had little impact in recent birth cohorts. Post-traumatic stress disorder accounted for most of the observed differences. Younger age at recruitment was associated with longer service, median 7.4 years (IQR 3.0–14.7) compared with 5.6 years (IQR 2.1–11.7) for entrants aged 20–25 years.ConclusionWe found no evidence that early recruitment is associated with adverse impact on long-term mental health. Paradoxically, it was veterans who entered service at age 20–25 years who demonstrated increased risk, although this attenuated in more recent birth cohorts.
Do Junior Entrants to the UK Armed Forces have worse outcomes than Standard Entrants?
Authors: Jones Margaret , Jones N , Burdett H , Bergman B P , Fear N T , Wessely S , Rona R J 
Published: April 2021

IntroductionThe UK is the only permanent member of the UN Security Council that has a policy of recruiting 16 and 17 year old individuals into its regular Armed Forces. Little is known about the consequences of enlisting as a Junior Entrant (JE), although concerns have been expressed. We compare the mental health, deployment history, and pre-enlistment and post-enlistment experiences of personnel who had enlisted as JEs with personnel who joined as Standard Entrants (SEs).MethodParticipants from a large UK military cohort study completed a self-report questionnaire between 2014 and 2016 that included symptoms of probable post-traumatic stress disorder (PTSD), common mental disorders, alcohol consumption, physical symptoms and lifetime self-harm. Data from regular non-officer participants (n=4447) from all service branches were used in the analysis. JEs were defined as having enlisted before the age of 17.5 years. A subgroup analysis of participants who had joined or commenced adult service after April 2003 was carried out.ResultsJEs were not more likely to deploy to Iraq or Afghanistan but were more likely to hold a combat role when they did (OR 1.25, 95% CI 1.00 to 1.56). There was no evidence of an increase in symptoms of common mental disorders, PTSD, multiple somatic symptoms (MSS), alcohol misuse or self-harm in JEs in the full sample, but there was an increase in alcohol misuse (OR 1.84, 95% CI 1.18 to 2.87), MSS (OR 1.51, 95% CI 1.04 to 2.20) and self-harm (OR 2.13, 95% CI 1.15 to 3.95) in JEs who had commenced adult service after April 2003. JEs remain in adult service for longer and do not have more difficulties when they leave service.ConclusionsJEs do not have worse mental health than SEs, but there is uncertainty in relation to alcohol misuse, MSS and self-harm in more recent joiners. Monitoring these concerns is advisable.
Gender differences in clinical presentation and illicit substance use during first episode psychosis: a natural language processing, electronic case register study
Authors: Irving Jessica , Colling Craig , Shetty Hitesh , Pritchard Megan , Stewart Robert , Fusar-Poli Paolo , McGuire Philip , Patel Rashmi 
Published: April 2021

ObjectiveTo determine whether gender differences in symptom presentation at first episode psychosis (FEP) remain even when controlling for substance use, age and ethnicity, using natural language processing applied to electronic health records (EHRs).Design, setting and participantsData were extracted from EHRs of 3350 people (62% male patients) who had presented to the South London and Maudsley NHS Trust with a FEP between 1 April 2007 and 31 March 2017. Logistic regression was used to examine gender differences in the presentation of positive, negative, depressive, mania and disorganisation symptoms.Exposure(s) (for observational studies)Gender (male vs female).Main outcome(s) and measure(s)Presence of positive, negative, depressive, mania and disorganisation symptoms at initial clinical presentation.ResultsEight symptoms were significantly more prevalent in men (poverty of thought, negative symptoms, social withdrawal, poverty of speech, aggression, grandiosity, paranoia and agitation). Conversely, tearfulness, low energy, reduced appetite, low mood, pressured speech, mood instability, flight of ideas, guilt, mutism, insomnia, poor concentration, tangentiality and elation were more prevalent in women than men. Negative symptoms were more common among men (OR 1.85, 95% CI 1.33 to 2.62) and depressive and manic symptoms more common among women (OR 0.30, 95% CI 0.26 to 0.35). After adjustment for illicit substance use, the strength of associations between gender and negative, manic and depression symptoms increased, whereas gender differences in aggression, agitation, paranoia and grandiosity became insignificant.ConclusionsThere are clear gender differences in the clinical presentation of FEP. Our findings suggest that gender can have a substantial influence on the nature of clinical presentation in people with psychosis, and that this is only partly explained by exposure to illicit substance use.
Measuring perceived adequacy of staffing to incorporate nurses’ judgement into hospital capacity management: a scoping review
Authors: van der Mark Carmen J E M , Vermeulen Hester , Hendriks Paul H J , Oostveen Catharina J van 
Published: April 2021

BackgroundMatching demand and supply in nursing work continues to generate debate. Current approaches focus on objective measures, such as nurses per occupied bed or patient classification. However, staff numbers do not tell the whole staffing story. The subjective measure of nurses’ perceived adequacy of staffing (PAS) has the potential to enhance nurse staffing methods in a way that goes beyond traditional workload measurement or workforce planning methods.ObjectivesTo detect outcomes associated with nurses’ PAS and the factors that influence PAS and to review the psychometric properties of instruments used to measure PAS in a hospital setting.Design and methodsA scoping review was performed to identify outcomes associated with PAS, factors influencing PAS and instruments measuring PAS. A search of PubMed, Cumulative Index to Nursing and Allied Health Literature (CINAHL), Business Source Complete and Embase databases identified 2609 potentially relevant articles. Data were independently extracted, analysed and synthesised. The quality of studies describing influencing factors or outcomes of PAS and psychometric properties of instruments measuring PAS were assessed following the National Institute for Health and Care Excellence quality appraisal checklist and the COnsensus-based Standards for the selection of health Measurement INstruments guidelines.ResultsSixty-three studies were included, describing 60 outcomes of PAS, 79 factors influencing PAS and 21 instruments measuring PAS. In general, positive PAS was related to positive outcomes for the patient, nurse and organisation, supporting the relevance of PAS as a staffing measure. We identified a variety of factors that influence PAS, including demand for care, nurse supply and organisation of care delivery. Associations between these factors and PAS were inconsistent. The quality of studies investigating the development and evaluation of instruments measuring PAS was moderate.ConclusionsMeasuring the PAS may enhance nurse staffing methods in a hospital setting. Further work is needed to refine and psychometrically evaluate instruments for measuring PAS.