bluuebunny/crossref_metadata_2025_split huggingface dataset:
Parallel Interval Algorithm for the Parameter Identification of Linear Elastomechanical Systems
Authors: Oeljeklaus Michael , Natke H. Günther 
Published: March 2021

Abstract
An interval analytical approach to parameter identification in the frequency domain of mathematical models for linear elasto-mechanical systems is described. A priori information, measurement errors and — if possible — unmeasurable degrees of freedom are modelled in terms of intervals. A parallel iterative update method — based on the interval analytical Gauss-Seidel method — is used to reduce the volume of the parameter search space initially given. The search for the global minimum of the WLS objective function using output residuals is performed on the reduced parameter space in a last step1. Subsystem identification and sub-model synthesis are used in the case of realistic models with a large number of degrees of freedom. Parallelization of the algorithm with respect to subsystems is applied in the case of large structures to reduce the amount of memory and to speed-up the computation. Test results for some simulations for a test structure are given in order to illustrate the method.
Efficient Eigenvector Sensitivities by a New Procedure Based Upon Lanczos Vectors
Authors: Ojalvo I. U. , Zhang L.-M. 
Published: March 2021

Abstract
A new Lanczos vector based procedure, for the efficient computation of eigenvector sensitivities to changes in system parameters, is presented in this paper. The method is based upon a matrix reduction which uses the identical Lanczos vectors as those used to obtain the original eigenvectors. Thus, the equation systems solved may be greatly reduced from the original matrix sizes. An explanation regarding why the method is most accurate, for the lowest eigenvectors’ derivatives, is offered. Numerical results for two modest sized examples are supplied, from which trends in the method’s accuracy are suggested.
Vibration of a Vertical Rotor Partially Filled With Liquid
Authors: Ide Katsuki , Kazao Yukihiko , Watanabe Shunzo , Yabu Tomohiko , Sakai Takuhiko 
Published: March 2021

Abstract
Using an experimental apparatus incorporating a hollow cylindrical rotor (partially filled with liquid) fitted to a vertically suspended shaft, we clarified the pressure mode shape, frequency, etc. of the liquid by directly measuring the pressure fluctuation while varying the amount of liquid and the rotating speed, and studied in detail the relationship between whirling vibration of the rotor and fluctuation of the liquid inside the rotor.
On that basis, we propose a practical method for estimating the region of unstable vibration. Results of estimation by this method were checked against the results of an experiment conducted using three types of differently shaped rotor.
According to many studies conducted in the past, the frequency of unstable vibration is almost constant. In the present experiment, however, the frequency of unstable vibration showed a characteristic tendency to increase with increasing rotational speed. The vibration that was observed in the experiment was found to be an unstable vibration caused chiefly by axial fluctuation of the liquid inside the rotor. It was also found that in the rotational speed range where the difference between the rotor rotating speed and the natural frequency of fluctuation of the free surface of the liquid becomes almost equal to the natural frequency of the rotor, a resonance occurs that causes the unstable vibration. Concerning the vibration studied here, we developed a practical method of estimating the region of unstable vibrations and showed that the method should be universally applicable.
Noncontacting Vibration Measurement Using a Massless Interferometric Accelerometer
Authors: Li Keyu 
Published: March 2021

Abstract
An interferometric strain measurement technique is extended to vibration measurements. The technique is based on two micro-indentations placed on an object surface using a combination of diffraction and interference of laser light. Relative displacements between the two indentations and derivatives of in-plane and out-of-plane vibrational displacements are measured by analyzing the phase shift of the interference fringe patterns. The technique can be used to study bending stress and deflection problems in vibrational beams, plates and shells. The displacement derivatives are measured in real time, from which time derivatives or the velocity and acceleration of the displacement derivative as well as vibrational frequency can be determined. The technique has advantages over an accelerometer in that it is noncontacting and does not require attachment of the transducer to the object which could alter the object behavior. In addition, it has many desirable features such as being extremely compact, massless, and applicable to hostile environments such as those associated with production and elevated temperatures.
Experimental Spatial Power Flow Using a Scanning Laser Doppler Vibrometer
Authors: Blotter Jonathan D. , West Robert L. 
Published: March 2021

Abstract
An experimental spatial power flow (ESPF) method which computes the energy path continuously over the surface of a vibrating structure is presented. The ESPF method is a novel approach based on a spatially dense representation of the system’s dynamics obtained by solving for the 3-D complex-valued velocity field from experimental data acquired by a scanning laser Doppler vibrometer (SLDV). Quintic B-spline surfaces used to represent the extracted velocity field allow the power flow to be computed continuously over the surface of the structure. The active and reactive power flow components are kept separate throughout the solution. To validate the ESPF concept, power flow results of a prescribed velocity field were compared with simulated experimental results. The power flow computed from the prescribed velocity field compared closely to the power flow computed from the simulated experimental results indicating the validity of the ESPF concept. The ESPF method was then applied to a simply supported thin steel plate. The experimental power flow results distinctly show the locations of the energy sources and sinks and identify the energy path in the plate.
Gastroenterological and hepatic manifestations of patients with COVID-19, prevalence, mortality by country, and intensive care admission rate: systematic review and meta-analysis
Authors: Shehab Mohammad , Alrashed Fatema , Shuaibi Sameera , Alajmi Dhuha , Barkun Alan 
Published: March 2021

Background and aimsPatients infected with the SARS-CoV-2 usually report fever and respiratory symptoms. However, multiple gastrointestinal (GI) manifestations such as diarrhoea and abdominal pain have been described. The aim of this study was to evaluate the prevalence of GI symptoms, elevated liver enzymes and mortality of patients with COVID-19.MethodsA systematic review and meta-analysis of published studies that included a cohort of patients infected with SARS-CoV-2 were performed from 1 December 2019 to 15 December 2020. Data were collected by conducting a literature search using PubMed, Embase, Scopus, and Cochrane according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. We analysed pooled data on the prevalence of individual GI symptoms and elevated liver enzymes and performed subanalyses to investigate the relationship between GI symptoms/elevated liver enzymes, geographical location, mortality, and intensive care unit (ICU) admission.ResultsThe available data of 78 798 patients positive for SARS-CoV-2 from 158 studies were included in our analysis. The most frequent manifestations were diarrhoea (16.5%, 95% CI 14.2% to 18.4%), nausea (9.7%, 95% CI 9.0% to 13.2%) and elevated liver enzymes (5.6%, 95% CI 4.2% to 9.1%). The overall mortality and GI mortality were 23.5% (95% CI 21.2% to 26.1%) and 3.5% (95% CI 3.1% to 6.2%), respectively. Subgroup analysis showed non-statistically significant associations between GI symptoms/elevated liver enzymes and ICU admissions (OR=1.01, 95% CI 0.55 to 1.83). The GI mortality was 0.9% (95% CI 0.5% to 2.2%) in China and 10.8% (95% CI 7.8% to 11.3%) in the USA.ConclusionGI symptoms/elevated liver enzymes are common in patients with COVID-19. Our subanalyses showed that the presence of GI symptoms/elevated liver enzymes does not appear to affect mortality or ICU admission rate. Furthermore, the proportion of GI mortality among patients infected with SARS-CoV-2 varied based on geographical location.
Correlates of e-cigarette use among active duty US military personnel: implications for cessation policy
Authors: Godby Sarah , Dierst-Davies R , Kogut D , Degiorgi Winslow L , Truslow M M , Tuttle J , Koeppl P , Marshall-Aiyelawo K , Elenberg K 
Published: March 2021

BackgroundElectronic cigarette (or e-cigarette) use has grown substantially since its US market introduction in 2007. Although marketed as a safer alternative to traditional cigarettes, studies have shown they can also be a gateway to their use. The purpose of this investigation is to identify factors associated with different patterns of tobacco use among active duty military personnel.MethodsA secondary analysis was conducted using the 2014 Defense Health Agency Health Related Behaviors survey data. Results are based on 45 986 US military respondents, weighted to 1 251 606. Both univariate and regression analyses were conducted to identify correlates.ResultsIn 2014, approximately 7.8% of respondents reported using e-cigarettes at least once in the past year. Among e-cigarette users, 49% reported exclusive e-cigarette use. Prevalence of exclusive use is highest among white people (58%), Navy (33%), men (83%) and persons with income ≤$45 000 (65%). Regression comparing exclusive cigarette with exclusive e-cigarette users revealed higher odds of being Air Force (OR=2.19; CI 1.18 to 4.06) or Navy (OR=2.25; CI 1.14 to 4.41) personnel and being male (OR=1.72; CI 1.12 to 2.64), and more likely to not receive smoking cessation messaging from healthcare providers in the last 12 months (OR=2.88; CI 1.80 to 4.62). When comparing exclusive e-cigarette users with poly-tobacco users, e-cigarette users had higher odds of being Hispanic (OR=2.20; CI 1.02 to 4.78), college educated (OR=4.25; CI 1.22 to 14.84) and not receiving tobacco prevention/cessation messaging (OR=4.80; CI 2.79 to 8.27).ConclusionThe results demonstrate that exclusive e-cigarette users in the military have unique characteristics when compared with groups of other/mixed tobacco users. Findings can inform cessation and prevention efforts to improve both the overall health and combat readiness of active duty military personnel.
Survey of the use of laser protective eyewear among international retina specialists: a European vitreoretinal society study
Authors: Siddiqui Mohammad Z , Ellabban Abdallah A , Soliman Mohamed K , Gini Giampaolo , Kurup Shree , Uwaydat Sami H , Sallam Ahmed B 
Published: March 2021

ObjectiveTo report the trends for the use of eye protection methods during retinal laser in clinic and operating room.Methods and analysisRetrospective analysis of a 14-item survey questionnaire submitted to the European Vitreoretinal Society members.ResultsResponses from 630 members were analysed. Most of the respondents practised in Europe (52.7%), followed by North America (21.0%). The majority of respondents had laser filters in the microscope for the operating surgeon (92.1%), or used protective goggles (6.8%). Only 38.9% of respondents indicated that auxiliary staff in the operative room used protective goggles during laser treatment. Three-dimensional retina viewing system was used by only 22.5% of respondents, of those, 34.5% reported use of laser protection goggles by the operating surgeon. Rates of laser protection by auxiliary staff were 62.9% for indirect laser and 60.8% for slit lamp laser. We found a higher rate for use of laser protection by auxiliary staff in North America-based practices for endolaser (p<0.00001), laser indirect ophthalmoscope (p<0.00001) and slit lamp laser (p=0.00033) compared with the rest of the world.ConclusionThe use of laser protection methods is routinely adopted by the physicians in the operating room and clinic, but less so by their assisting or auxiliary staff.
Driving quality improvement with a massive open online course (MOOC)
Authors: Guest Cheryl , Wainwright Philip , Herbert Margaret , Smith Iain Murray 
Published: March 2021

BackgroundQuality improvement (QI) is a priority for national regulatory bodies in health and care in the UK. However, many health and care staff do not know where to go for support in gaining the required skills and knowledge in QI. This paper reviews Improvement Fundamentals, a massive open online course (MOOC), designed to address this gap, run by an improvement team in the national regulatory body.MethodsIn 2015, National Health Service (NHS) Improving Quality (subsequently the sustainable improvement team in NHS England) established Improvement Fundamentals: a programme of online, self-directed courses in QI for those involved in heath or social care. The programme ran in two cycles: twice in 2015, followed by a re-launch in 2018 (this programme also ran into 2019). A mixed-methods evaluation was carried out of the 2015 programme involving surveys, interviews and social listening. The 2018–2019 programme was evaluated using post-course surveys of participants and activity data from the platform.OutcomesSince the start of the 2015 programme, 604 improvement projects have been developed, run and submitted for formal assessment, with some demonstrating clear improvements in services. Themes from participant feedback on both programmes have included improved understanding of QI tools and methods; greater energy for QI; a greater sense of community and connectedness in participants’ work and increased confidence in using QI tools and techniques.DiscussionBoth programmes delivered benefits for participants, and the team’s investment in improvement skills on these programmes has helped to increase capability for future change endeavours. The collaborative nature of the programmes has been key to their successes.ConclusionImprovement Fundamentals demonstrates that MOOCs can be instrumental in driving forward improvements in health and care. The programmes may have utility as a model for future MOOCs, both in QI and other topics, to help drive further improvements in health and care.
Decision-making for the infant sleep environment among families with children considered to be at risk of sudden unexpected death in infancy: a systematic review and qualitative metasynthesis
Authors: Pease Anna , Garstang Joanna J , Ellis Catherine , Watson Debbie , Ingram Jenny , Cabral Christie , Blair Peter S , Fleming Peter J 
Published: March 2021

BackgroundAdvice to families to sleep infants on their backs, avoid smoke exposure, reduce excess bedcovering and avoid specific risks associated with cosleeping has greatly reduced sudden unexpected death in infancy (SUDI) rates worldwide. The fall in rates has not been equal across all groups, and this advice has been less effective for more socially deprived families. Understanding decision-making processes of families with infants at risk would support the development of more effective interventions.AimTo synthesise the qualitative evidence on parental decision-making for the infant sleep environment among families with children considered to be at increased risk of SUDI.MethodsThis study was one of three related reviews of the literature for the Child Safeguarding Practice Review Panel’s National Review in England into SUDI in families where the children are considered at risk of harm. A systematic search of eight online databases was carried out in December 2019. Metasynthesis was conducted, with themes extracted from each paper, starting with the earliest publication first.ResultsThe wider review returned 3367 papers, with 16 papers (across 13 studies) specifically referring to parental decision-making. Six overall themes were identified from the synthesis: (1) knowledge as different from action; (2) external advice must be credible; (3) comfort, convenience and disruption to the routine; (4) plausibility and mechanisms of protection; (5) meanings of safety and risk mitigation using alternative strategies; and (6) parents’ own expertise, experience and instincts.ConclusionInterventions that are intended to improve the uptake of safer sleep advice in families with infants at risk of sleep-related SUDI need to be based on credible advice with mechanisms of protection that are understandable, consistent with other sources, widened to all carers of the infant and fit within the complex practice of caring for infants.
Association between influenza vaccination and hospitalisation or all-cause mortality in people with COVID-19: a retrospective cohort study
Authors: Wilcox Christopher R , Islam Nazrul , Dambha-Miller Hajira 
Published: March 2021

IntroductionRecent evidence suggests that influenza vaccination may offer protection against COVID-19 severity. Our aim was to quantify the association between influenza vaccination status and risk of hospitalisation or all-cause mortality in people diagnosed with COVID-19.MethodsA retrospective cohort study using routinely collected health records from patients registered to a General Practitioner (GP) practice in South West England within the Electronic Care and Health Information Analytics database. The cohort included 6921 people with COVID-19 during the first wave of the pandemic (1 January–31 July 2020). Data on influenza vaccination, hospitalisation and all-cause mortality were ascertained through linked clinical and demographic records. We applied propensity score methods (stabilised inverse probability of treatment weight) to quantify the association between influenza vaccination status and COVID-19 outcomes (hospitalisation or all-cause mortality).Results2613 (38%) participants received an influenza vaccination between 1 January 2019 and COVID-19 diagnosis. Receipt of influenza vaccination was associated with a significantly lower odds of hospitalisation or all-cause mortality (adjusted OR: 0.85, 95% CI 0.75 to 0.97, p=0.02), and 24% reduced odds of all-cause mortality (adjusted OR: 0.76, 95% CI 0.64 to 0.90).DiscussionInfluenza vaccination was associated with a 15%–24% lower odds of severe COVID-19 outcomes. The current UK influenza vaccination programme needs urgent expansion as an integral component of the ongoing response plans to the COVID-19 pandemic.
‘It’s not one size fits all’: a qualitative study of patients’ and healthcare professionals’ views of self-management for bronchiectasis
Authors: Kelly Carol Ann , Tsang Anthony , Lynes Dave , Spencer Sally 
Published: March 2021

BackgroundBronchiectasis is a chronic respiratory condition that impacts significantly on individuals and healthcare services. Self-management is recommended in clinical guidelines for bronchiectasis as an intervention to enable patients to manage their condition, yet there is little evidence to support it.MethodsThree face to face focus groups (17 adults with bronchiectasis) were conducted at three National Health Service (NHS) sites in North West England. Additionally, semi-structured telephone interviews were undertaken with 11 healthcare professionals (HCPs), including doctors, nurses and physiotherapists. Thematic analysis identified common themes and occurrences verified by independent audit.FindingsFour common overarching themes were identified:the meaning of self-management;benefits;barriersandinfluencers to self-management; subthemes varied. Both groups recognised component interventions. Patients highlighted that self-management enabled them to learn what works and moderate behaviour. Aspects of delivery and structure were important to HCPs but a ‘make do’ culture was evident. Benefits for both groups included empowering patients. Common barriers for patients were time, mood and lack of access to support which could mitigate engagement with self-management. HCPs identified barriers including patient characteristics and lack of resources. Influencers for patients were peer, carer and psychosocial support, for HCPs influencers were individual patient attributes, including ability and motivation, and HCP characteristics such as knowledge and understanding about bronchiectasis.SummaryThis is the first study to explore patients’ and HCPs’ views of self-management for bronchiectasis. The need for an individual, flexible and responsive self-management programme specific to bronchiectasis was evident. Personal characteristics of patients and HCPs could affect the uptake and engagement with self-management and HCPs knowledge of the disease is a recognised precursor to effective self-management. The study identified key aspects for consideration during development, delivery and sustainability of self-management programmes and findings suggest that patients’ psychosocial and socioeconomic circumstances may affect adoption and activation of self-management behaviours.
Gender differences in mental health symptoms and risk factors in Australian elite athletes
Authors: Walton Courtney C , Rice Simon , Gao Caroline X , Butterworth Matt , Clements Matti , Purcell Rosemary 
Published: March 2021

ObjectivesTo examine gender differences in the reporting of, and contributors to, mental health symptoms.MethodsThis was a cross-sectional observational study of adult athletes within a national elite sporting system (n=523; women=292;56%), who completed a battery of assessments including measures of mental health and adverse life events. Group differences across a range of scores were examined, followed by gender-stratified bootstrapped linear regression and meta-regression on measures where gender differences were observed.ResultsWomen athletes reported higher rates of mental health symptoms, and lower rates of mental well-being, although there were no differences in general psychological distress or life satisfaction. Women reported experiencing several adverse life events at higher rates than men; particularly interpersonal conflict, financial hardship and discrimination. Low self-esteem was consistently associated with poorer mental health outcomes for all athletes. While a range of factors were associated with poor mental health in men or women athletes, meta-regression suggested that experiencing financial difficulty and social media abuse were more uniquely associated with mental health symptoms in men.ConclusionGender differences in mental health in elite athletes are apparent. Approaches to increasing well-being are required in elite sport.