bluuebunny/crossref_metadata_2025 huggingface dataset:
Effects of Surface Waviness on Fan Blade Boundary Layer Transition and Profile Loss—Part II: Experimental Assessments and Applications
Authors: Lee Jinwook , Ramaswamy Vaishnavi , Spakovszky Zoltán S. , Greitzer Edward M. , Drela Mark , Talbotec Jérôme
Published: August 2021

Part II describes the experimental assessment and the application of the ideas in Part I concerning the mechanisms that determine the role of blade surface waviness on laminar-turbulent transition and their consequent effect on civil aircraft fan performance. A natural transition wind tunnel was designed and constructed to characterize the impact of surface waviness on transition, using both hotwire anemometry and infrared thermography. The experimental results support the new hypothesis presented in Part I, concerning the way in which blade surface waviness affects fan performance through motion of the transition onset location due to interaction between surface waviness and Tollmien–Schlichting (TS) boundary layer instability. In particular, the theoretical amplification of the TS waves, and the corresponding transition onset location movement due to surface waviness, was borne out over a range of variations in Reynolds number, nondimensional surface wavelength, nondimensional surface wave height, and location of surface wave initiation, relevant to composite fan blade parameters. Further, the increase of receptivity coefficient, and thus, the initial amplitude of disturbances due to geometric resonance between surface wavelength and TS wavelength was also confirmed by the experiments. Surface waviness was estimated, in some cases, to result in a nearly 1% decrease in fan efficiency compared to a nonwavy blade. Suggestions are given for mitigation of the effects of waviness, including the idea of blade curvature rescheduling as a method to delay transition and thus decrease loss.
Applied Deep Learning for Slender Marine Structure Dynamic Analysis
Authors: da Silva Vinicius Ribeiro Machado , Sagrilo Luis Volnei Sudati , de Araujo Breno Serrano
Published: August 2021

Nonlinear finite element models (FEMs) are commonly used to perform analysis in the time domain to simulate a limited number of stochastic loading scenarios that a slender marine structure may undergo, requiring a high computational time effort. Analytical equations and frequency domain analysis can be used to speed up these simulations, but they are not a convenient choice when high nonlinearities are present in the dynamic system. Alternative models can be developed to reduce the simulation time while maintaining a good accuracy level of the system’s response. This work proposes different strategies to develop artificial neural network (ANN) architectures, based on deep learning (DL) algorithms, which can predict multiple structural node responses at once, in time and space, significantly reducing the total training time when a great number of structural nodes are considered. A novel classification concept of ANN-based models is introduced for this application: the NodeNet and the LengthNet class types. In the first approach, the model predictor focuses on a single structural node, while in the latter the model focuses on a length (segment) comprising many structural nodes. The work also extends the response predictions of such marine structures from the top region down to the touchdown zone (TDZ).
Finite Element Simulation of Axisymmetric Elastic and Electroelastic Wave Propagation Using Local-Domain Wave Packet Enrichment
Authors: Kumar Amit , Kapuria Santosh
Published: August 2021

A local-domain wave packet enriched multiphysics finite element (FE) formulation is employed for accurately solving axisymmetric wave propagation problems in elastic and piezoelastic media, involving complex wave modes and sharp jumps at the wavefronts, which pose challenges to the conventional FE solutions. The conventional Lagrangian interpolations for the displacement and electric potential fields are enriched with the element-domain sinusoidal functions that satisfy the partition of unity condition. The extended Hamilton’s principle is employed to derive the coupled system of equations of motion which is solved using the simple Newmark-β direct time integration scheme without resorting to any remeshing near the wavefronts or post-processing. The performance of the enrichment is assessed for the axisymmetric problems of impact waves in elastic and piezoelectric cylinders and elastic half-space, bulk and Rayleigh waves in the semi-infinite elastic domain and ultrasonic Lamb wave actuation and propagation in plate-piezoelectric transducer system. The element shows significant improvement in the computational efficiency and accuracy over the conventional FE for all problems, including those involving multiple complex wave modes and sharp discontinuities in the fields at the wavefronts.
Vocal fold dynamics in a synthetic self-oscillating model: Intraglottal aerodynamic pressure and energy
Authors: Motie-Shirazi Mohsen , Zañartu Matías , Peterson Sean D. , Erath Byron D.
Published: August 2021

Self-sustained oscillations of the vocal folds (VFs) during phonation are the result of the energy exchange between the airflow and VF tissue. Understanding this mechanism requires accurate investigation of the aerodynamic pressures acting on the VF surface during oscillation. A self-oscillating silicone VF model was used in a hemilaryngeal flow facility to measure the time-varying pressure distribution along the inferior-superior thickness of the VF and at four discrete locations in the anterior-posterior direction. It was found that the intraglottal pressures during the opening and closing phases of the glottis are highly dependent on three-dimensional and unsteady flow behaviors. The measured aerodynamic pressures and estimates of the medial surface velocity were used to compute the intraglottal energy transfer from the airflow to the VFs. The energy was greatest at the anterior-posterior midline and decreased significantly toward the anterior/posterior endpoints. The findings provide insight into the dynamics of the VF oscillation and potential causes of some VF disorders.
A history of jet noise research at the National Aeronautics and Space Administration
Authors: Henderson Brenda S. , Huff Dennis L.
Published: August 2021

This paper reviews jet noise research conducted at the National Aeronautics and Space Administration (NASA) from the early 1950s to the present day. Research conducted by NASA's predecessor, the National Advisory Committee for Aeronautics (NACA), and during the early years of NASA focused on turbojet noise, where a common approach for reducing jet noise was to limit the jet exit velocity to speeds that provided acceptable noise levels. Suppressors tested during this time resulted in thrust losses that were too severe to be implemented. With the introduction of turbofan engines in the 1960s, NASA shifted research to programs for both subsonic and supersonic aircraft applications with specific noise reduction goals. Subsonic research focused on increasing the bypass ratio of the engine to reduce the jet exit velocity of the core exhaust and adding mixers to the dual exhaust streams. Advances in computational methods improved aerodynamic designs and jet noise prediction tools. Supersonic applications proved to be more troublesome as programs aimed at large commercial transports required higher specific thrust engines. Changing the engine cycle to reduce jet noise was not compatible with mission range and speed requirements. Research for supersonic commercial aircraft remains an area of interest today at NASA.
An extra-broadband compact sound-absorbing structure composing of double-layer resonator with multiple perforations
Authors: Guo Jingwen , Fang Yi , Qu Renhao , Liu Qian , Zhang Xin
Published: August 2021

Based on multi-layer Helmholtz resonators with extended necks (HREN), a compact sound-absorbing structure is developed for extra-broadband sound absorption. The structure of HREN with a single perforation is beneficial for low-frequency absorption under a thin thickness. However, it faces the problem of effectively attenuating noise only within a narrow frequency bandwidth near the resonance frequency. To widen its effective absorption bandwidth, two potential solutions are proposed and evaluated: (1) increasing the perforation number, and (2) adding extra layers in series. Results reveal that more perforations produce a wider half-absorption bandwidth, and the added layers induce more absorption peaks. Thus, a multi-layer HREN unit with multiple perforations is a favorable candidate for broadband sound absorption. On the basis of these, we design a broadband acoustic structure constructed by 11 coupled parallelly arranged double-layer HREN units with multiple perforations. The structure possesses an average sound-absorption coefficient of 0.9 in a prescribed frequency ranging from 800 to 3000 Hz. The absorption effectiveness of the structure is validated via experiments. What is more, the dimension of the absorber is only 50 mm (long)×50 mm (width)×41 mm (depth), indicating its compact characteristic. Hence, the developed extra broadband and compact sound-absorbing structure possesses a promising potential in various engineering applications.
Type I interferon autoantibodies are associated with systemic immune alterations in patients with COVID-19
Authors: van der Wijst Monique G. P. , Vazquez Sara E. , Hartoularos George C. , Bastard Paul , Grant Tianna , Bueno Raymund , Lee David S. , Greenland John R. , Sun Yang , Perez Richard , Ogorodnikov Anton , Ward Alyssa , Mann Sabrina A. , Lynch Kara L. , Yun Cassandra , Havlir Diane V. , Chamie Gabriel , Marquez Carina , Greenhouse Bryan , Lionakis Michail S. , Norris Philip J. , Dumont Larry J. , Kelly Kathleen , Zhang Peng , Zhang Qian , Gervais Adrian , Le Voyer Tom , Whatley Alexander , Si Yichen , Byrne Ashley , Combes Alexis J. , Rao Arjun Arkal , Song Yun S. , Fragiadakis Gabriela K. , Kangelaris Kirsten , Calfee Carolyn S. , Erle David J. , Hendrickson Carolyn , Krummel Matthew F. , Woodruff Prescott G. , Langelier Charles R. , Casanova Jean-Laurent , Derisi Joseph L. , Anderson Mark S. , Ye Chun Jimmie ,   on behalf of the UCSF COMET consortium
Published: August 2021

Type I interferon autoantibodies in patients with COVID-19 are associated with poor interferon responses and increased LAIR1 abundance in leukocytes.
Highly Basic Clusters in the Herpes Simplex Virus 1 Nuclear Egress Complex Drive Membrane Budding by Inducing Lipid Ordering
Authors: Thorsen Michael K. , Lai Alex , Lee Michelle W. , Hoogerheide David P. , Wong Gerard C. L. , Freed Jack H. , Heldwein Ekaterina E.
Published: August 2021

Herpesviruses are large viruses that infect nearly all vertebrates and some invertebrates and cause lifelong infections in most of the world’s population. During replication, herpesviruses export their capsids from the nucleus into the cytoplasm by an unusual mechanism in which the viral nuclear egress complex (NEC) deforms the nuclear membrane around the capsid.
Serine Metabolism Tunes Immune Responses To Promote
Oreochromis niloticus
Survival upon
Edwardsiella tarda
Infection
Authors: Yang Dai-Xiao , Yang Man-Jun , Yin Yue , Kou Tian-Shun , Peng Liao-Tian , Chen Zhuang-Gui , Zheng Jun , Peng Bo
Published: August 2021

Bacterial virulence factors are not the only factors responsible for host death. Overactive immune responses, such as cytokine storm, contribute to tissue injury that results in organ failure and ultimately the death of the host.
Comparative Genomics Reveals a Remarkable Biosynthetic Potential of the
Streptomyces
Phylogenetic Lineage Associated with Rugose-Ornamented Spores
Authors: Chung Yoon-Hee , Kim Hiyoung , Ji Chang-Hun , Je Hyun-Woo , Lee Dongho , Shim Sang Hee , Joo Hwang-Soo , Kang Hahk-Soo
Published: August 2021

It is now well recognized that members of the genus
Streptomyces
still harbor a large number of cryptic BGCs in their genomes, which are mostly silent under laboratory culture conditions. Activation of transcriptionally silent BGCs is technically challenging and thus forms a bottleneck when taking a gene-first approach for the discovery of new natural products.
Evolution in a Community Context: towards Understanding the Causes and Consequences of Adaptive Evolution in the Human Gut Microbiota over Short Time Scales
Authors: Scanlan Pauline Deirdre
Published: August 2021

How important is adaptive evolution to the unique diversity that we can observe for each individual human gut microbiome? How do gut microbes evolve in response to changes in their environment, and how does evolution in real time impact microbial functionality in the context of host health? My interdisciplinary research uses
in vitro
microcosm models to test how different abiotic and biotic factors impact microbial evolution in a community context. We complement this approach by tracking focal species as they evolve in real time and in their natural environment of the human gut.
Metabolomics in Functional Interrogation of Individual Holobiont Members
Authors: Garg Neha
Published: August 2021

Eukaryotes and their environments serve as petri dishes, hosting an abundant and a rich prokaryotic microbiome. The assemblage of a eukaryotic host and its microbiome is referred to as a holobiont.
Role of the Discriminator Sequence in the Supercoiling Sensitivity of Bacterial Promoters
Authors: Forquet Raphaël , Pineau Maïwenn , Nasser William , Reverchon Sylvie , Meyer Sam
Published: August 2021

In this study, we highlight the role of the discriminator as a global sensor of supercoiling variations and propose the first quantitative regulatory model of this principle, based on the specific step of promoter opening during transcription initiation. It defines the predictive rule by which SC quantitatively modulates the expression rate of bacterial promoters, depending on the G/C content of their discriminator and independently from promoter-specific regulatory proteins.
Lead screening in children presenting to three hospitals in Lebanon
Authors: El Zahran Tharwat , Mostafa Hala , Hamade Hani , Al Hariri Moustafa , Saab Aed , Tamim Hani , Tohme Rasha , Al Hamod Dany A , Sinno Durriyah , Sawaya Rasha Dorothy , Kazzi Ziad
Published: August 2021

Background

Lead damages most body organs and its effects are most profound in children. In a study in Beirut in 2003, before banning the leaded gasoline, 79% of the participants showed blood lead levels (BLLs) higher than 5 µg/dL. The prevalence of lead exposure in Lebanon after the ban on leaded gasoline has not been studied. This study assessed the BLL in Lebanese children aged 1–6 years.

Methods

This cross-sectional study was conducted in three hospitals in Beirut. The children’s BLLs were tested, and their caregiver completed a questionnaire to identify subgroups at risk of exposure. Participants were provided with a WHO brochure highlighting the risks of lead.

Results

Ninety children with a mean age of 3.5±1.5 years were enrolled in the study and had a mean BLL of 1.1±0.7 µg/dL, with all values being below 5.0 µg/dL, showing a marked decrease in BLL compared with the mean BLL before the ban on leaded gasoline in 2002. Having a father or a mother with a college degree (p=0.01 and p=0.035, respectively) and having a monthly household income greater than $1000 (p=0.021) were associated with significantly lower BLL. Having more rooms at home and residing close to construction sites were associated with a significantly lower BLL (p=0.001 and p=0.026, respectively). Residing in a house aged >40 years and receiving traditional remedies were associated with a significantly higher BLL (p=0.009 and p<0.0001, respectively).

Conclusion

BLLs have declined among Lebanese children and this could be attributed to multiple factors including the ban of leaded gasoline. It would be beneficial to conduct a larger study with a nationally representative sample to better characterise the BLL.
COVID-19 lockdown measures induced severe iron-deficiency anaemia resulting in central retinal vein occlusion and amenorrhea
Authors: Kwan Yu Heng , Woong Natalie Liling , Foo Reuben Chao Ming , Balakrishnan Tharmmambal
Published: August 2021

During the COVID-19 pandemic, precautionary measures taken by various countries include individual movement restrictions causing significant lifestyle changes and affecting dietary patterns. A 23-year-old woman presented with reduced left eye vision over 1 week and amenorrhea for 4 months. She was diagnosed with severe iron-deficiency anaemia causing central retinal vein occlusion and amenorrhea. During the lockdown, there was a change in her diet with greatly reduced iron intake. Iron is an essential mineral for retina metabolism and function. Iron supplementation was done with improvement in her vision. This case demonstrates the potential impact of lockdown measures on nutrition and health. Education of the general population on maintaining appropriate nutrition during periods of movement restriction is important and that nutritional evaluation and supplementation should be considered in patients with drastic changes in dietary pattern.
Synovial fluid cell count of 84 930/mm3in adult-onset Still’s disease
Authors: Winberg Carter , Ladak Karim
Published: August 2021

In traditional teaching, synovial fluid cell counts over 50 000/mm3are in keeping with septic or crystalline arthritis. We report a patient with adult-onset Still’s disease (AOSD) and associated inflammatory arthritis whose synovial fluid cell count was over 80 000/mm3. This is the highest level reported in the literature, demonstrating that in the appropriate clinical context, markedly elevated synovial cell count levels over 50 000/mm3can be caused by inflammatory conditions like AOSD. Recognition of this is crucial to avoid inappropriate antibiotics and procedures while also ensuring correct immunosuppressive treatments are offered in a timely manner.
Effectiveness and safety of acupuncture therapy for inflammatory bowel disease: a protocol of systematic review and meta-analysis
Authors: Zhou Yuan-Fang , Sun Ning , Cheng Shi-Rui , Deng Xiao-Dong , Ye Xiang-Yin , Li Zheng-Jie , Zhou Jun , Xu Gui-Xing , Qu Yu-Zhu , Huang Liu-Yang , Sun Rui-Rui , Liang Fan-Rong
Published: August 2021

Introduction

Previous reviews have suggested that the effectiveness of acupuncture for inflammatory bowel disease (IBD) has not well been demonstrated due to the limited randomised controlled trials (RCTs). In recent years, the growing research on acupuncture for IBD make it possible to conduct a further systematic review and synthesise more sufficient clinical data to evaluate the effectiveness and safety of acupuncture for IBD.

Methods and analysis

Nine electronic databases without language restriction will be retrieved from inception to March 2021, including the Cochrane Library, MEDLINE, EMBASE, Ovid, the Allied and Complementary Medicine Database, China National Knowledge Infrastructure, Chinese Biomedical Literature Database, the Chongqing Chinese Science and Technology Periodical Database and Wanfang Database. The RCTs on acupuncture for IBD will be included. The data screening, data extraction and the assessment of risk bias will be performed respectively by two reviewers. The quality of evidence will be evaluated by using the Grading of recommendation Assessment, Development and Evaluation application. The meta-analysis will be performed if heterogeneity analysis conducted on the RevMan software (V.5.3) is insignificant. The primary outcome was symptoms alleviation after acupuncture treatment or even in the follow-up.

Ethics and dissemination

Ethical approval will not be needed because data of this review are not involved in patient’s information and privacy. The results will be published and diffused in a peer-reviewed journal or relative conferences.

Trial registration number

CRD42020157903.
Use of targeted mobile X-ray screening and computer-aided detection software to identify tuberculosis among high-risk groups in Romania: descriptive results of the E-DETECT TB active case-finding project
Authors: Mahler Beatrice , de Vries Gerard , van Hest Rob , Gainaru Dan , Menezes Dee , Popescu Gilda , Story Alistair , Abubakar Ibrahim
Published: August 2021

Objective

To implement and assess the mobile X-ray unit (MXU) equipped with digital radiography, computer-aided detection (CAD) software and molecular point of care tests to improve early tuberculosis (TB) diagnosis in vulnerable populations in a TB outreach screening programme in Romania.

Design

Descriptive study.

Settings

Prisons in Bucharest and other cities in the southern part of Romania, homeless shelters and services for problem drug users in Bucharest, and Roma populations in Bucharest and Craiova.

Participants

5510 individuals attended the MXU service; 5003 persons were radiologically screened, 61% prisoners, 15% prison staff, 11% Roma population, 10% homeless persons and/or problem drug users and 3% other.

Interventions

Radiological digital chest X-ray (CXR) screening of people at risk for TB, followed by CAD and human reading of the CXRs, and further TB diagnostics when the pulmonologist classified the CXR as suggestive for TB.

Primary and secondary outcome measures

Ten bacteriologically confirmed TB cases were identified translating into an overall yield of 200 per 100 000 persons screened (95% CIs of 109 to 368 per 100 000). Prevalence rates among homeless persons and/or problem drug users (826/100 000; 95% CI 326 to 2105/100 000) and the Roma population (345/100 000; 95% CI 95 to 1251/100 000) were particularly high.

Results

The human reader classified 6.4% (n=317) of the CXRs as suspect for TB (of which 32 were highly suggestive for TB); 16.3% of all CXRs had a CAD4TB version 6 score >50. All 10 diagnosed TB patients had a CAD4TB score >50; 9 had a CAD4TB score >60.

Conclusions

Given the high TB prevalence rates found among homeless persons and problem drug users and in the Roma population, targeted active case finding has the potential to deliver a major contribution to TB control in Romania.
Assessing the impact of sports and recreation facility density within school neighbourhoods on Canadian adolescents’ substance use behaviours: quasi-experimental evidence from the COMPASS study, 2015–2018
Authors: Doggett Amanda , Godin Katelyn M , Schell Olena , Wong Suzy L , Jiang Ying , Leatherdale Scott T
Published: August 2021

Objectives

There has been relatively little exploration to date of potential protective effects within school neighbourhoods, such as those conferred by facilities that seek to promote health with respect to substance use and related harms. This study examined how the density of sports and recreation facilities in the school neighbourhood is associated with the likelihood of binge drinking, e-cigarette use, cigarette smoking and cannabis use among Canadian secondary school students.

Design

Longitudinal data from the COMPASS study on Canadian youth health behaviours from 2015/2016 to 2017/2018 was linked with school neighbourhood data capturing the number of sports and recreation facilities within a 1500 m radius of schools.

Setting

Secondary schools and school neighbourhoods in Alberta, British Columbia, Ontario and Quebec who participated in the COMPASS study.

Participants

16 471 youth who participated in the COMPASS study over three school years (2015/2016–2017/2018).

Primary and secondary outcome measures

Binge drinking, e-cigarette use, cigarette use, cannabis use.

Results

Logistic regression models using generalised estimating equations identified that greater density of sports and recreation facilities within the school neighbourhood was significantly associated with lower likelihood of binge drinking and e-cigarette use but was not associated with cigarette smoking or cannabis use.

Conclusions

This research can help to support evidence-informed school community-based efforts to prevent substance-related harms among youth.
Medicinal plants used among pregnant women in a tertiary teaching hospital in Jimma, Ethiopia: a cross-sectional study
Authors: Ahmed Seid Mussa , Sundby Johanne , Aragaw Yesuf Ahmed , Nordeng Hedvig
Published: August 2021

Objective

The aim of this study was to investigate and describe the use of medicinal plants during pregnancy among women admitted in the Maternity and Gynaecology wards at Jimma University Medical Centre (JUMC) in the southwest Ethiopia.

Design

Cross-sectional study.

Setting

Maternity and Gynaecology wards at JUMC.

Participants

1117 hospitalised pregnant women or postpartum women.

Main outcome measures

Our primary outcomes of interest were the prevalence of use, types of medicinal plants used and their utilisation among pregnant women.

Methods

Data were collected through structured face-to-face interviews of pregnant women or postpartum women and review of patient medical records between February and June 2017.

Results

Overall, 28.6% of the women reported use of at least one medicinal plant during the pregnancy. Twenty-seven different types of medicinal plants were used. The most commonly used medicinal plants wereLinum usitatissimumL. (flaxseed—use with caution) 22.0%,Ocimum lamiifoliumL. (damakessie—safety unknown) 3.6% andCarica papayaL. (papaya—use with caution) 3.1%. The most common reason for use was preparation, induction or shortening of labour. Lack of access to health facility (mainly health posts), admission to maternity ward,khatchewing and alcohol consumption were the strongest predictors of medicinal plants use during pregnancy (OR >2). Only five medicinal plants used by women had sufficient evidence to be classified as safe to use in pregnancy.

Conclusions

Almost one-third of women at the tertiary hospital in Ethiopia reported use of medicinal plants during pregnancy, most frequently to prepare, induce, reduce the intensity or shorten duration of labour. Increased awareness about potential benefits or risks of medicinal plants use during pregnancy among healthcare professionals and patients, and increased access to childbirth providing healthcare facilities are important in order to promote safer pregnancies and better health outcomes for women and their unborn children.
Recruitment challenges to the I CARE study: a randomised trial on general practitioner-led colon cancer survivorship care
Authors: Duineveld Laura A M , Vos Julien A M , Wieldraaijer Thijs , Donkervoort Sandra C , Wind Jan , van Weert Henk C P M , van Asselt Kristel M
Published: August 2021

Objectives

The I CARE study (Improving Care After colon canceR treatment in the Netherlands) aims to compare surgeon-led to general practitioner (GP)-led colon cancer survivorship care. Recruitment to the trial took longer than expected. In this descriptive study, recruitment is critically reviewed.

Setting

Patients were recruited from eight Dutch medical centres.

Participants

Patients treated with curative intent for stages I–III colon cancer. Target patient sample size was calculated at 300.

Interventions

Patients were randomised to surgeon-led (usual) versus GP-led care, with or without access to an eHealth application (Oncokompas).

Outcome measures

Baseline characteristics of (non-)participants, reasons for non-participation and strategies to improve recruitment were reviewed.

Results

Out of 1238 eligible patients, 353 patients were included. Of these, 50 patients dropped out shortly after randomisation and before start of the intervention, resulting in a participation rate of 25%. Participants were on average slightly younger (68.1 years vs 69.3 years) and more often male (67% vs 50%) in comparison to non-participants. A total of 806 patients declined participation for reasons most often relating to research (57%), including the wish to remain in specialist care (31%) and too much effort to participate (12%). Some patients mentioned health (9%) and confrontation with the disease (5%) as a reason. In 43 cases, GPs declined participation, often related to the study objective, need for financial compensation and time restraints. The generally low participation rate led to concerns about reaching the target sample size. Methods to overcome recruitment challenges included changes to the original recruitment procedure and the addition of new study centres.

Conclusions

Challenges were faced in the recruitment to a randomised trial on GP-led colon cancer survivorship care. Research on the transition of care requires sufficient time, funding and support base among patients and healthcare professionals. These findings will help inform researchers and policy-makers on the development of future practices.

Trial registration number

NTR4860.
Systematic review of the factors and the key indicators that identify doctors at risk of complaints, malpractice claims or impaired performance
Authors: Austin Elizabeth E , Do Vu , Nullwala Ruqaiya , Fajardo Pulido Diana , Hibbert Peter D , Braithwaite Jeffrey , Arnolda Gaston , Wiles Louise K , Theodorou Tahlia , Tran Yvonne , Lystad Reidar P , Hatem Sarah , Long Janet C , Rapport Frances , Pantle Annette , Clay-Williams Robyn
Published: August 2021

Objective

To identify the risk factors associated with complaints, malpractice claims and impaired performance in medical practitioners.

Design

Systematic review.

Data sources

Ovid-Medline, Ovid Embase, Scopus and Cochrane Central Register of Controlled Trials were searched from 2011 until March 2020. Reference lists and Google were also handsearched.

Results

Sixty-seven peer-reviewed papers and three grey literature publications from 2011 to March 2020 were reviewed by pairs of independent reviewers. Twenty-three key factors identified, which were categorised as demographic or workplace related. Gender, age, years spent in practice and greater number of patient lists were associated with higher risk of malpractice claim or complaint. Risk factors associated with physician impaired performance included substance abuse and burn-out.

Conclusions

It is likely that risk factors are interdependent with no single factor as a strong predictor of a doctor’s risk to the public. Risk factors for malpractice claim or complaint are likely to be country specific due to differences in governance structures, processes and funding. Risk factors for impaired performance are likely to be specialty specific due to differences in work culture and access to substances. New ways of supporting doctors might be developed, using risk factor data to reduce adverse events and patient harm.

PROSPERO registration number

PROSPERO registration number: CRD42020182045.
Improving medical residents’ utilisation of integrated mental health in primary care
Authors: Palladino Jenna , Frum-Vassallo Deirdra , Taylor Joanne D , Webb Victoria L
Published: August 2021

Background

Integration of mental health services allows for improved prevention and management of chronic conditions within the primary care setting. This quality improvement project aimed to increase adherence to and functioning of an integrated care model within a patient-centred medical home. Specifically, the project focused on improving collaboration between Primary Care Mental Health Integration (PC-MHI) and the medical resident Patient Aligned Care Teams (PACT) at a Veterans Affairs Medical Center in Northport,New York (VAMC Northport).

Method

The project used increased education, training and relationship building among the medical resident PACTs, and the establishment of regularly occurring integrated team meetings for medical and mental health providers. Education of residents was measured with a self-assessment pre-training and post-training, while utilisation was measured by the percentage of patients currently on a PACT’s panel with at least one PC-MHI encounter in the last 12 months (known in VAMC Northport as PACT-15 metric).

Results

Two resident PACTs that received both training and weekly integrated meetings increased their utilisation of integrated mental health services by 3.8% and 4.5%, respectively. PACTs that participated in training only, with no regular meetings, showed an initial improvement in utilisation that declined over time.

Conclusions

Training alone appeared beneficial but insufficient for increased integration over time. The addition of a regularly occurring integrated weekly meeting may be a critical component of facilitating sustained mental health integration in a primary care medical home model.
Maternal obesity, pregnancy weight gain, and birth weight and risk of colorectal cancer
Authors: Murphy Caitlin C , Cirillo Piera M , Krigbaum Nickilou Y , Singal Amit G , Lee MinJae , Zaki Timothy , Burstein Ezra , Cohn Barbara A
Published: August 2021

Objective

Colorectal cancer (CRC) is a leading cause of cancer-related death worldwide. Obesity is a well-established risk factor for CRC, and fetal or developmental origins of obesity may underlie its effect on cancer in adulthood. We examined associations of maternal obesity, pregnancy weight gain, and birth weight and CRC in adult offspring.

Design

The Child Health and Development Studies is a prospective cohort of women receiving prenatal care between 1959 and 1966 in Oakland, California (N=18 751 live births among 14 507 mothers). Clinical information was abstracted from mothers’ medical records 6 months prior to pregnancy through delivery. Diagnoses of CRC in adult (age ≥18 years) offspring were ascertained through 2019 by linkage with the California Cancer Registry. We used Cox proportional hazards models to estimate adjusted HR (aHR); we examined effect measure modification using single-referent models to estimate the relative excess risk due to interaction (RERI).

Results

68 offspring were diagnosed with CRC over 738 048 person-years of follow-up, and half (48.5%) were diagnosed younger than age 50 years. Maternal obesity (≥30 kg/m2) increased the risk of CRC in offspring (aHR 2.51, 95% CI 1.05 to 6.02). Total weight gain modified the association of rate of early weight gain (RERI −4.37, 95% CI −9.49 to 0.76), suggesting discordant growth from early to late pregnancy increases risk. There was an elevated association with birth weight (≥4000 g: aHR 1.95, 95% CI 0.8 to 4.38).

Conclusion

Our results suggest that in utero events are important risk factors for CRC and may contribute to increasing incidence rates in younger adults.
Fostering intrinsic motivation in remote undergraduate histopathology education
Authors: Uraiby Hussein , Grafton-Clarke Ciaran , Gordon Morris , Sereno Marco , Powell Barbara , McCarthy Mark
Published: August 2021

Aims

The levels of abstraction, vast vocabulary and high cognitive load present significant challenges in undergraduate histopathology education. Self-determination theory describes three psychological needs which promote intrinsic motivation. This paper describes, evaluates and justifies a remotely conducted, post-COVID-19 histopathology placement designed to foster intrinsic motivation.

Methods

90 fourth-year medical students took part in combined synchronous and asynchronous remote placements integrating virtual microscopy into complete patient narratives through Google Classroom, culminating in remote, simulated multidisciplinary team meeting sessions allowing participants to vote on ‘red flag’ signs and symptoms, investigations, histological diagnoses, staging and management of simulated virtual patients. The placement was designed to foster autonomy, competence and relatedness, generating authenticity, transdisciplinary integration and clinical relevance. A postpositivistic evaluation was undertaken with a validated preplacement and postplacement questionnaire capturing quantitative and qualitative data.

Results

There was a significant (p<0.001) improvement in interest, confidence and competence in histopathology. Clinical integration and relevance, access to interactive resources and collaborative learning promoted engagement and sustainability post-COVID-19. Barriers to online engagement included participant lack of confidence and self-awareness in front of peers.

Conclusions

Fostering autonomy, competence and relatedness in post-COVID-19, remote educational designs can promote intrinsic motivation and authentic educational experiences. Ensuring transdisciplinary clinical integration, the appropriate use of novel technology and a focus on patient narratives can underpin the relevance of undergraduate histopathology education. The presentation of normal and diseased tissue in this way can serve as an important mode for the acquisition and application of clinically relevant knowledge expected of graduates.
Effects of exercise training in people with non-small cell lung cancer before lung resection: a systematic review and meta-analysis
Authors: Gravier Francis-Edouard , Smondack Pauline , Prieur Guillaume , Medrinal Clement , Combret Yann , Muir Jean-François , Baste Jean-Marc , Cuvelier Antoine , Boujibar Fairuz , Bonnevie Tristan
Published: August 2021

Introduction

Exercise training before lung resection for non-small cell lung cancer is believed to decrease postoperative complications (POC) by improving cardiorespiratory fitness. However, this intervention lacks a strong evidence base.

Aim

To assess the effectiveness of preoperative exercise training compared with usual care on POC and other secondary outcomes in patients with scheduled lung resection.

Methods

A systematic search of randomised trials was conducted by two authors. Meta-analysis was performed, and the effect of exercise training was estimated by risk ratios (RR) and mean differences, with their CIs. Clinical usefulness was estimated according to minimal important difference values (MID).

Results

Fourteen studies involving 791 participants were included. Compared with usual care, exercise training reduced overall POC (10 studies, 617 participants, RR 0.58, 95% CI 0.45 to 0.75) and clinically relevant POC (4 studies, 302 participants, Clavien-Dindo score ≥2 RR 0.42, 95% CI 0.25 to 0.69). The estimate of the effect of exercise training on mortality was very imprecise (6 studies, 456 participants, RR 0.66, 95% CI 0.20 to 2.22). The main risks of bias were a lack of participant blinding and selective reporting. Exercise training appeared to improve exercise capacity, pulmonary function and also quality of life and depression, although the clinical usefulness of the changes was unclear. The quality of the evidence was graded for each outcome.

Conclusion

Preoperative exercise training leads to a worthwhile reduction in postoperative complications. These estimates were both accurate and large enough to make recommendations for clinical practice.
Precision enhancement of smartphone sensor-based pavement roughness estimation by standardizing host vehicle speed
Authors: Janani L. , Doley Rashmi , Sunitha V. , Mathew Samson
Published: August 2021

Condition assessment of pavement has a predominant part in delivering safety and comfort to users. Roughness is considered the most important characteristic as it affects road safety and vehicle operating costs. Authorities spend significant quantity of resources on using conventional methods for measuring roughness. Many researches are performed to estimate roughness by deploying smartphone sensors. However, no consideration is given to the influence of the speed of the host vehicle in roughness evaluation using smartphones. This work explains a smartphone sensor-based roughness evaluation technique by deploying the quarter car simulation model. The accuracy is checked with the simultaneously collected international roughness index (IRI) measured by a roughometer. Results of the smartphone-based pavement roughness estimation experiment showed a high correlation value of 0.73, and proved the accuracy of the method. The data were segregated based on three speed ranges. The correlation between the smartphone-based and roughometer-based IRI for all ranges was analyzed, and the R2 value of 0.75 was exhibited for 31–50 km/h range.
Kerr–Schild metrics in teleparallel gravity
Authors: Fröb Markus B.
Published: August 2021

We show that the Kerr–Schild ansatz can be extended from the metric to the tetrad, and then to teleparallel gravity where curvature vanishes but torsion does not. We derive the equations of motion for the Kerr–Schild null vector, and describe the solution for a rotating black hole in this framework. It is shown that the solution depends on the chosen tetrad in a non-trivial way if the spin connection is fixed to be the one of the flat background spacetime. We show furthermore that any Kerr–Schild solution with a flat background is also a solution of $$f({\mathcal {T}})$$

f
(
T
)

gravity.
Constrains on the electric charges of the binary black holes with GWTC-1 events
Authors: Wang Hai-Tang , Li Peng-Cheng , Jiang Jin-Liang , Yuan Guan-Wen , Hu Yi-Ming , Fan Yi-Zhong
Published: August 2021

Testing black hole’s charged property is a fascinating topic in modified gravity and black hole astrophysics. In the first Gravitational-Wave Transient Catalog (GWTC-1), ten binary black hole merger events have been formally reported, and these gravitational wave signals have significantly enhanced our understanding of the black hole. In this paper, we try to constrain the amount of electric charge with the parameterized post-Einsteinian framework by treating the electric charge as a small perturbation in a Bayesian way. We find that the current limits in our work are consistent with the result of Fisher information matrix method in previous works. We also develop a waveform model considering a leading order charge effect for binary black hole inspiral.
Diffusion and flow across shape-perturbed plasmodesmata nanopores in plants
Authors: Christensen Anneline H. , Stone Howard A. , Jensen Kaare H.
Published: August 2021

Plasmodesmata are slender nanochannels that link neighboring plant cells and enable the exchange of nutrients and signaling molecules. Recent experiments have demonstrated significant variability in the concentric pore shape. However, the impact of these geometric fluctuations on transport capacity is unknown. Here, we consider the effects on diffusion and advection of two ideal shape perturbations: a radial displacement of the entire central desmotubule and a harmonic variation in the cytoplasmic sleeve width along the length of the pore. We use Fick’s law and the lubrication approximation to determine the diffusive current and volumetric flow rate across the pore. Our results indicate that an off-center desmotubule always increases the pressure-driven flow rate. However, the diffusive current is only enhanced for particles comparable in size to the width of the channel. In contrast, harmonic variations in the cytoplasmic sleeve width along the length of the pore reduce both the diffusive current and the pressure-driven flow. The simple models presented here demonstrate that shape perturbations can significantly influence transport across plasmodesmata nanopores.
A Hybrid Method to Obtain the Wheel–Rail Contact Point at Extreme Positions
Authors: Jiang Lizhong , Chen Yuanjun , Li Changqing , Li Jing , Liu Xiang , He Weikun
Published: August 2021

When conducting a numerical simulation of a train’s derailment and post-derailment, it is necessary to continuously observe the relative position of the wheel and rail, which is of great significance for the correct evaluation of train safety. In this paper, a non-analytic method is proposed to extend the search range and improve the accuracy of the classical semi-analytical method, i.e. the contact locus method. Based on the point cloud convex hull, a high-density wheel contact locus vertical profile is obtained by projecting the chamfer and internal zone of the flange onto the rail cutting plane. To obtain maximum compression in the normal direction and avoid singularities on both rail head sides in the Cartesian coordinate system the rail surface is interpolated with the polar spline curve. Compared with the classical method used to describe the wheel contact locus, in the proposed hybrid method, potential contact points are provided. Finally, the proposed hybrid method and the classical methods are applied to the wheel track coupling simulation. Numerical results demonstrate the high reliability and effectiveness of the proposed method.
Analytical Solution for Longitudinal Dynamic Responses of Long Tunnels under Arbitrary Excitations
Authors: Yu Haitao , Chen Xizhuo , Chen Weile , Li Pan
Published: August 2021

In this paper, an analytical solution is proposed for longitudinal dynamic responses of long tunnels under arbitrary excitations. For the derivation, the tunnel is assumed as a Timoshenko beam resting on a visco-Pasternak foundation. The Timoshenko beam theory is employed to consider both effects of the shear distortion as well as the rotary inertia of the tunnel, which are neglected by the Euler–Bernoulli beam. The visco-Pasternak foundation is applied to represent the viscoelastic compressive and shear resistance of soil. The governing equations of motion are transformed from partial differential forms into algebraic forms through integral transformations, and thus the solutions are conveniently obtained. The analytical solutions of the tunnel under several specific dynamic loads, including impulsive loads, moving line loads as well as traveling loads, are presented in detail and verified by comparing to the known degraded solution in literature and finite element results. Several examples are also conducted to investigate the influence of the relative stiffness ratio between the soil and the tunnel structure on the tunnel responses.
Energetic, Exergetic, Environmental, and Economic Assessment of a Cascade Refrigeration System Operating with Four Different Ecological Refrigerant Pairs
Authors: de Paula Cleison Henrique , Duarte Willian Moreira , Rocha Thiago Torres Martins , de Oliveira Raphael Nunes , Maia Antônio Augusto Torres
Published: August 2021

In this work, a cascade refrigeration system operating with four different ecological refrigerant pairs was modeled. This system uses R744 (Carbon dioxide) in the low-temperature cycle and operates with R290 (propane), R1234yf (2,3,3,3-tetrafluoropropene), R152a (1,1-difluorethane), and R717 (ammonia) in the high-temperature cycle. Energetic, exergetic, environmental, and economic performance of the cascade system was investigated to determine the most appropriate ecological refrigerant couple. The parameters used in each mentioned performance were COP (Coefficient of Performance), [Formula: see text] (Exergy Efficiency), TEWI (Total Equivalent Warming Impact), ECOP (Ecological coefficient of performance), and [Formula: see text] (Total plant cost rate), respectively. The results showed that the cascade refrigeration system operating with R744/R717 provided the best performance for the thermodynamic conditions analyzed, presenting a COP of 2.10, [Formula: see text] of 56.9%, [Formula: see text] of 24 334 USD/year, ECOP of 4.86, and TEWI of 25.67 tons of CO2. Finally, evaluating the total plant cost rate of this cascade system, it was noted that the capital and maintenance cost rate [Formula: see text] corresponds to 89.1% of the [Formula: see text] value, the operational cost rate [Formula: see text] corresponds to 10.27% of the [Formula: see text] value and the environmental cost rate [Formula: see text] corresponds to 0.63% of [Formula: see text].
Shared Decision Making
Authors: Wang Wei
Published: August 2021

Shared decision making (SDM) is a process by which physicians and patients jointly participate in choosing to pursue one of several alternatives in a clinical decision. It is most relevant for decisions that involve significant potential harms and benefits with tradeoffs and uncertainty. This paper provides a state-of-the-art review about SDM covering its concept, value, implementation and application in emergency management and communication. SDM is valuable in the process of making decisions which patients may benefit most from, thus resulting in satisfying patient-centered outcomes. Although SDM can be challenging to incorporate into clinical practice, it is likely to become a useful tool of communication in future.