bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of Tethered Swimming as Postactivation Potentiation on Swimming Performance and Technical, Hemophysiological, and Psychophysiological Variables in Adolescent Swimmers
Authors: Abbes Zied , Haddad Monoem , Bibi Khalid W. , Mujika Iñigo , Martin Cyril , Chamari Karim
Published: May 2020

Objectives: To investigate whether tethered swimming (TS) performed 8 minutes before a 50-m freestyle swimming sprint could be an effective postactivation potentiation method to improve performance in young swimmers. Methods: Fourteen regional-level male adolescent swimmers (age 13.0 [2.0] y; height 161.1 [12.4] cm; body mass 52.5 [9.5] kg) underwent 2 trial conditions in a randomized and counterbalanced order (1 experimental [TS], 1 control) on different days. During the experimental session, the participants performed a standard warm-up of 1200 m followed by a TS exercise, which consisted of 3 × 10-second maximal efforts of TS with 1-minute rests between bouts. In the control condition, the warm-up phase was immediately followed by 200 m at a moderate pace (same duration as the TS in the experimental session). Performance (time trial); biomechanical (stroke length), physiological (blood lactate concentrations), and psychophysiological (ratings of perceived exertion) variables; and countermovement-jump (CMJ) flight time were collected. Results: TS warm-up had no significant effect on 50-m swimming performance (P = .27), postexercise ratings of perceived exertion, stroke length, or CMJ flight time (P ≥ .05). Blood lactate concentrations significantly increased at the end of the warm-up in the TS condition only (interaction effect: F1.91,29.91 = 4.91, P = .01, η2 = .27) and after the 50-m trial in both conditions (F1.57,20.41 = 62.39, P = .001, η2 = .82). Conclusions: The present study demonstrated that 3 × 10-second TS exercises performed 8 minutes prior to the event did not affect ratings of perceived exertion, stroke length, or CMJ flight time. In addition, tethered swimming did not affect 50-m freestyle sprint performance in young swimmers.
Effect of a Marathon on Skin Temperature Response After a Cold-Stress Test and Its Relationship With Perceptive, Performance, and Oxidative-Stress Biomarkers
Authors: Priego-Quesada Jose Ignacio , Pérez-Guarner Alejandro , Gandia-Soriano Alexis , Oficial-Casado Fran , Galindo Carlos , Cibrián Ortiz de Anda Rosa M. , Piñeiro-Ramos José David , Sánchez-Illana Ángel , Kuligowski Julia , Gomes Barbosa Marco A. , Vento Máximo , Salvador Palmer Rosario
Published: May 2020

Context: Although skin-temperature assessment has received much attention in recent years as a possible internal-load measurement, scientific evidence is scarce. Purpose: To analyze baseline skin temperature and its rewarming through means of a cold-stress test before and after performing a marathon and to study the association between skin temperature and internal/external-load measurements. Methods: A total of 16 runners were measured 48 and 24 h before and 24 and 48 h after completing a marathon. The measurements on each day of testing included urine biomarkers of oxidative stress, pain and fatigue perception, skin temperature (at baseline and after a cold-stress test), and jump performance. Results: Reduced jump performance (P < .01 and effect size [ES] = 0.5) and higher fatigue and pain perception were observed 24 h after the marathon (P < .01 and ES > 0.8). Although no differences in baseline skin temperature were observed between the 4 measuring days, posterior legs presented lower constant (P < .01 and ES = 1.4) and higher slope (P = .04 and ES = 1.1) parameters in the algorithmic equations fitted for skin-temperature recovery after the cold-stress test 24 h after the marathon than on the day before the marathon. Regressions showed that skin-temperature parameters could be predicted by the ratio of ortho-tyrosine isomer to phenylalanine (oxidative stress biomarker) and body fat composition, among others. Conclusions: Although baseline skin temperature was not altered 24 or 48 h after a marathon, the application of cold stress after the marathon would appear to be a good method for providing information on vasoconstriction and a runner’s state of stress.
Multiyear Square Dancing Is Associated With Superior Mental Processing Capacity But Not Memory in Middle-Aged and Older Chinese Women: A Cross-Sectional Propensity Score Matching Analysis
Authors: Liao Jing , Yang Yung-Jen , Xu Dong (Roman)
Published: May 2020

Background: Evidence suggests the importance of physical activity and social engagement in cognitive preservation. Group-based dancing combining exercise and prosocial features may generate physical and cognitive benefits.Objectives: To investigate the association between multiyear habitual square dancing and domain-specific cognitive function, and assess the relative importance and joint impact of physical activity and social activity on cognition.Methods: Using the cross-sectional propensity score matching method, the study compared the mental status, episodic memory, and overall cognitive performances of 145 amateur female square-dancing participants (aged ≥45 y) to their sociodemographic- and health-status–matched 222 nondancing counterparts, selected from the China Health and Retirement Longitudinal Study.Results: The authors found a positive association between multiyear square dancing (average 8 y) and overall cognitive performances (mean difference = 2.84; 95% confidence interval [CI], 1.65 to 4.02), which was apparent in processing capacity (2.29; 95% CI, 1.51 to 3.07) but not in memory (0.55; 95% CI, −0.13 to 1.23). The hypothesized synergic effect of physical activity and social activity on cognition was only observed in group-based exercises embodying these 2 components simultaneously.Conclusions: Long-term square dancing as one type of physically and socially engaging activities may preserve cognition. Future longitudinal and interventional studies are needed to further clarify the causal relationship.
Competencies for a Healthy Physically Active Lifestyle—Reflections on the Model of Physical Activity-Related Health Competence
Authors: Carl Johannes , Sudeck Gorden , Pfeifer Klaus
Published: May 2020

Background: The World Health Organization’s Global Action Plan on Physical Activity 2018–2030 states that physical activity interventions should strengthen peoples’ competencies for health. Yet, frameworks that bundle pivotal competencies for a healthy and physically active lifestyle have not been extensively discussed in the past. Results: In the present article, the authors therefore present the model of Physical Activity-related Health Competence (PAHCO), an integrative structure model including the 3 areas of movement competence, control competence, and self-regulation competence. After providing a rationale for the use of the competence concept, the authors focus on implications from the PAHCO model to guide interventions for the promotion of a healthy and physically active lifestyle. The authors argue that the PAHCO model is located at the interface between health literacy and physical literacy, research areas that have gained increasing scholarly attention in recent years. In addition, PAHCO appears to be compatible with the concept of health capability because it can represent the important aspect of agency. Conclusions: The article concludes with a scientific positioning of model components and some empirical results that have been accumulated so far.
Fitness-Related Self-Conscious Emotions and Risk for Exercise Addiction: Examining the Mediating Role of Passion
Authors: Sicilia Alvaro , Alcaraz-Ibáñez Manuel , Dumitru Delia C. , Paterna Adrian , Griffiths Mark D.
Published: May 2020

Fitness-related self-conscious emotions (SCEs) have been proposed as antecedents of exercise addiction (EA). However, the potential mechanisms underlying such a relationship remain unexplored. The present study examined the relationship between fitness-related SCEs and risk of EA, as well as the mediating role of passion for exercise. A total of 296 male runners (M = 40.35 years, SD = 10.69) completed a survey assessing weekly exercise frequency/hours, fitness-related SCEs, passion for exercise, and the risk of EA. The relationships between the study variables were examined using structural equation modeling. After controlling for age and weekly exercise frequency/hours, fitness-related SCEs of shame, guilt, and hubristic pride were positively associated with risk of EA. However, while guilt had direct effects on risk of EA, shame and hubristic pride showed indirect effects via obsessive passion. The results of the study are discussed, and some practical implications and future research directions are presented.
Developing Student-Athlete School Satisfaction and Psychological Well-Being: The Effects of Academic Psychological Capital and Engagement
Authors: Kim Minjung , Oja Brent D. , Kim Han Soo , Chin Ji-Hyoung
Published: May 2020

The quality of a student-athlete’s experience can be a product of the services provided by their sponsoring sport organization. In an attempt to improve the student-athlete experience, this study was positioned to examine how collegiate sport services could use academic psychological capital (PsyCap) and student-athlete engagement to promote school satisfaction and psychological well-being. A total of 248 National Collegiate Athletic Association Division I student-athletes participated in this study. Results indicated that academic classification moderated academic PsyCap’s influence on engagement. In addition, the academic PsyCap of the student-athletes positively influenced school satisfaction and psychological well-being, but student-athlete engagement fully mediated the relationship between academic PsyCap and psychological well-being. This empirical evidence provides new knowledge on the relationships among student-athletes’ motivational cognitive constructs, educational engagement, school satisfaction, and psychological well-being in the context of highly competitive collegiate sports. Theoretical and practical implications are discussed, including incorporating the results with services provided to student-athletes.
Applying the Sport Commitment Model to Sport Injury Rehabilitation
Authors: Weiss Windee M.
Published: May 2020

Context: Sustaining effort and persistence throughout injury rehabilitation are common goals for sport health care professionals. Considerable research in the sport domain has explored the issue of commitment to sport, as well as what predicts or influences an athlete’s continued desire and resolve to continue participation. Scanlan and colleagues developed the sport commitment model (SCM) that places enjoyment as central construct influencing athletes’ commitment. According to the model, perceptions of enjoyment, personal investments, involvement opportunities, attractive alternatives, social constraints, and social support should predict an athlete’s level of sport commitment. One could argue the same may be true for commitment to sport injury rehabilitation. By applying the SCM to sport injury rehabilitation, practitioners may be able to enhance an athlete’s commitment to their rehabilitation, prolong adherence, and increase other positive outcomes, such as increased enjoyment, motivation, and successful return to competition. Objective: The purpose of this pilot study was to explore the applicability of the SCM to the injury rehabilitation setting. Design: Correlational design was used. Setting: Division I, intercollegiate athletic training room. Participants: 51 injured intercollegiate male and female athletes, 5 certified athletic trainers, and 8 senior, athletic training students. Intervention: At the approximate midpoint of each athlete’s injury rehabilitation, participants completed SCM measures. Certified athletic trainers and senior athletic training students independently assessed each injured athlete on effort, energy, and intensity during rehabilitation sessions. Main Outcome Measures: Rehabilitation commitment, enjoyment, investments, attractive alternatives, social constraints, perceived costs, and rehabilitation behaviors. Results: Higher perceptions of investments predicted rehabilitation commitment. However, none of the SCM determinants predicted athletic trainer–rated rehabilitation behaviors. Conclusions: Future research should continue to explore commitment constructs in relation to rehabilitation motivation.
The Relationship Between Injury-Related Fear and Visuomotor Reaction Time in Individuals With a History of Anterior Cruciate Ligament Reconstruction
Authors: Genoese Francesca , Baez Shelby E. , Heebner Nicholas , Hoch Matthew C. , Hoch Johanna M.
Published: May 2020

Context: Deficits in reaction time, decreased self-reported knee function, and elevated levels of injury-related fear have been observed in individuals who sustain anterior cruciate ligament injury. Understanding the relationship between these variables may provide the impetus to further investigate effective intervention strategies to address these deficits in individuals after anterior cruciate ligament reconstruction (ACLR). Objective: To examine the relationship between injury-related fear and lower-extremity visuomotor reaction time (VMRT) in individuals with a history of ACLR. A secondary purpose was to determine the relationship between self-reported knee function and lower-extremity VMRT in individuals with a history of ACLR. Design: Cross-sectional study. Setting: Laboratory. Participants: Twenty participants between the ages of 18–35 years, with history of unilateral ACLR within the last 10 years, who injured their knee playing or training for organized or recreational sports. Main Outcome Measures: Scores on the athlete fear avoidance questionnaire, the fear-avoidance beliefs questionnaire (FABQ), the knee injury and osteoarthritis outcome score, and reaction time (in seconds) on the lower-extremity VMRT task using the FitLight Trainer™, bilaterally. Spearman Rho correlations examined the relationship between the dependent variables. Results: There was a moderate positive correlation between VMRT and FABQ-total (r = .62, P < .01), FABQ-sport (r = .56, P = .01), and FABQ-physical activity (r = .64, P < .01) for the injured limb. Correlations between FABQ scores and VMRT for the uninjured limb were weak positive correlations (r = .36–.41, P > .05). Weak correlations between the osteoarthritis outcome score subscales, athlete fear avoidance questionnaire, and VMRT were observed for the injured limb (P > .05). Conclusions: Individuals with a history of ACLR who exhibited elevated levels of injury-related fear demonstrated slower VMRT. There were no relationships between self-reported knee function and VMRT. Future research should explore interventions to address injury-related fear and VMRT in individuals after ACLR.
Generation of self-organized sensory ganglion organoids and retinal ganglion cells from fibroblasts
Authors: Xiao Dongchang , Deng Qinqin , Guo Yanan , Huang Xiuting , Zou Min , Zhong Jiawei , Rao Pinhong , Xu Zihui , Liu Yifan , Hu Youjin , Shen Yin , Jin Kangxin , Xiang Mengqing
Published: May 2020

Generation of sensory ganglion organoids and retinal ganglion cells from fibroblasts for research and therapeutic applications.
‘Building on shaky ground’—challenges to and solutions for primary care guideline implementation in four provinces in South Africa: a qualitative study
Authors: Kredo Tamara , Cooper Sara , Abrams Amber Louise , Muller Jocelyn , Schmidt Bey-Marrié , Volmink Jimmy , Atkins Salla
Published: May 2020

Objectives

Clinical guidelines support evidence-informed quality patient care. Our study explored perspectives of South African subnational health managers regarding barriers to and enablers for implementation for all available primary care guidelines.

Design

We used qualitative research methods, including semistructured, individual interviews and an interpretative perspective. Thematic content analysis was used to develop data categories and themes.

Setting

We conducted research in four of nine South African provinces with diverse geographic, economic and health system arrangements (Eastern Cape, Western Cape, KwaZulu-Natal, Limpopo). South Africa is a middle-income country with high levels of inequality. The settings represented public sector rural and peri-urban health facilities.

Participants

Twenty-two participants with provincial and district health management roles, that comprised implementation and/or training on primary care guidelines, were included.

Results

Participants recommended urgent consideration of health system challenges, particularly financial constraints, impacting on access to the guidelines themselves and to medical equipment and supplies necessary to adhere to guidelines. They suggested that overcoming service delivery gaps requires strengthening of leadership, clarification of roles and enhanced accountability. Participants suggested that inadequate numbers of skilled clinical staff hampered guideline use and, ultimately, patient care. Quality assurance of training programmes for clinicians—particularly nurses—interdisciplinary training, and strengthening post-training mentorship were recommended. Furthermore, fit-for-purpose guideline implementation necessitates considering the unique settings of facilities, including local culture and geography. This requires guideline development to include guideline end users.

Conclusions

Guidelines are one of the policy tools to achieve evidence-informed, cost-effective and universal healthcare. But, if not effectively implemented, they have no impact. Subnational health managers in poorly resourced settings suggested that shortcomings in the health system, along with poor consultation with end users, affect implementation. Short-term improvements are possible through increasing access to and training on guidelines. However, health system strengthening and recognition of socio-cultural–geographic diversity are prerequisites for context-appropriate evidence-informed practice.
Population Registry of Esophageal and Stomach Tumours in Ontario (PRESTO): protocol for a multicentre clinical and pathological database including 25 000 patients
Authors: Gupta Vaibhav , Levy Jordan , Allen-Ayodabo Catherine , Amirazodi Elmira , Davis Laura , Li Qing , Mahar Alyson , Coburn Natalie G
Published: May 2020

Introduction

Oesophagogastric cancers carry a high mortality, economic burden and rising incidence. There is a need to monitor and improve care for this disease. Pathologic information is a cornerstone of cancer diagnosis, treatment and prognosis. Few population-based studies combine pathology information and clinical outcomes. The objective of this study is to develop a clinical and pathological database of oesophagogastric cancers to study practice patterns, resource utilisation and clinical outcomes.

Methods and analysis

The Population Registry of Esophageal and Stomach Tumours in Ontario (PRESTO) will include all patients with oesophagogastric cancer diagnosed from 2002 onwards within the province of Ontario. We estimate that the sample over the first 14 years of the study will include 26 000 patients. Pathologic information from diagnostic procedures, endomucosal resection specimens and surgical resection specimens is being abstracted into a purpose-built database. Pathology information will be linked to administrative data, which capture baseline demographics, patient-reported symptoms, physician billings, hospital visits, hospital characteristics, geography and vital statistics. The registry will be updated prospectively.

Ethics and dissemination

Ethics approval for this study was obtained from the Sunnybrook Health Sciences Centre Research Ethics Board. The PRESTO database will enable the study of oesophagogastric cancer in Ontario under six themes of inquiry: treatment, surgical outcomes, pathology, survival, health system and resource utilisation and cost. This information will be a valuable addition to the global efforts to understand ways to optimise care for these diseases.
Cohort profile: the Singapore diabetic cohort study
Authors: Luo Miyang , Tan Linda Wei Lin , Sim Xueling , Ng Milly Khiam Hoon , Van Dam Rob , Tai E Shyong , Chia Kee Seng , Tang Wern Ee , Seah Darren EJ , Venkataraman Kavita
Published: May 2020

Purpose

The diabetic cohort (DC) was set up to study the determinants of complications in individuals with type 2 diabetes and examine the role of genetic, physiological and lifestyle factors in the development of complications in these individuals.

Participants

A total of 14 033 adult participants with type 2 diabetes were recruited from multiple public sector polyclinics and hospital outpatient clinics in Singapore between November 2004 and November 2010. The first round of follow-up was conducted for 4131 participants between 2012 and 2016; the second round of follow-up started in 2016 and is expected to end in 2021. A questionnaire survey, physical assessments, blood and urine sample collection were conducted at recruitment and each follow-up visit. The data set also includes genetic data and linkage to medical and administrative records for recruited participants.

Findings to date

Data from the cohort have been used to identify determinants of diabetes and related complications. The longitudinal data of medical records have been used to analyse diabetes control over time and its related outcomes. The cohort has also contributed to the identification of genetic loci associated with type 2 diabetes and diabetic kidney disease in collaboration with other large cohort studies. About 25 scientific papers based on the DC data have been published up to May 2019.

Future plans

The rich data in DC can be used for various types of research to study disease-related complications in patients with type 2 diabetes. We plan to further investigate disease progression and new biomarkers for common diabetic complications, including diabetic kidney disease and diabetic neuropathy.
Improving quality of surgical and anaesthesia care at hospital level in sub-Saharan Africa: a systematic review protocol of health system strengthening interventions
Authors: Brima Nataliya , Davies Justine , Leather Andrew JM
Published: May 2020

Introduction

Over 5 billion people in the world do not have access to safe, affordable surgical and anaesthesia care when needed. In order to improve health outcomes in patients with surgical conditions, both access to care and the quality of care need to be improved. A recent commission on high-quality health systems highlighted that poor-quality care is now a bigger barrier than non-utilisation of the health system for reducing mortality.

Aim

To carry out a systematic review to provide an evidence-based summary of hospital-based interventions associated with improved quality of surgical and anaesthesia care in sub-Saharan African countries (SSACs).

Methods and analysis

Three search strings (1) surgery and anaesthesia, (2) quality improvement hospital-based interventions and (3) SSACs will be combined. The following databases EMBASE, Global Health, MEDLINE, CINAHL, Web of Science and Scopus will be searched. Further relevant studies will be identified from national and international health organisations and publications and reference lists of all selected full-text articles. The review will include all type of original articles in English published between 2008 and 2019. Article screening, data extraction and assessment of methodological quality will be done by two reviewers independently and any disputes will be resolved by a third reviewer or team consensus. Three types of outcomes will be collected including clinical, process and implementation outcomes. The primary outcome will be mortality. Secondary outcomes will include other clinical outcomes (major and minor complications), as well as process and implementation outcomes. Descriptive statistics and outcomes will be summarised and discussed. For the primary outcome, the methodological rigour will be assessed.

Ethics and dissemination

The results will be published in a peer reviewed open access journal and presented at national and international conferences. As this is a review of secondary data no formal ethical approval is required.

PROSPERO registration number

CRD42019125570.
Continuous renal replacement therapy in cytokine release syndrome following immunotherapy or cellular therapies?
Authors: Constantinescu Catalin , Pasca Sergiu , Tat Tiberiu , Teodorescu Patric , Vlad Catalin , Iluta Sabina , Dima Delia , Tomescu Dana , Scarlatescu Ecaterina , Tanase Alina , Sigurjonsson Olafur Eysteinn , Colita Anca , Einsele Hermann , Tomuleasa Ciprian
Published: May 2020

Recently, an increasing number of novel drugs were approved in oncology and hematology. Nevertheless, pharmacology progress comes with a variety of side effects, of which cytokine release syndrome (CRS) is a potential complication of some immunotherapies that can lead to multiorgan failure if not diagnosed and treated accordingly. CRS generally occurs with therapies that lead to highly activated T cells, like chimeric antigen receptor T cells or in the case of bispecific T-cell engaging antibodies. This, in turn, leads to a proinflammatory state with subsequent organ damage. To better manage CRS there is a need for specific therapies or to repurpose strategies that are already known to be useful in similar situations. Current management strategies for CRS are represented by anticytokine directed therapies and corticosteroids. Based on its pathophysiology and the resemblance of CRS to sepsis and septic shock, as well as based on the principles of initiation of continuous renal replacement therapy (CRRT) in sepsis, we propose the rationale of using CRRT therapy as an adjunct treatment in CRS where all the other approaches have failed in controlling the clinically significant manifestations.
Research progress in the effects of pectus excavatum on cardiac functions
Authors: Liu Caixia , Wen Yunhong
Published: May 2020

Background

Pectus excavatum, the most common chest wall deformity in children, accounts for nearly 90% of congenital malformations of chest wall. Initially, both parents and doctors paid more attention to the influence of this deformity on patient appearance and psychology. Following deeper studies of pectus excavatum, researchers found that it also affected cardiac functions. The purpose of this review aims to present recent research progress in the effects of pectus excavatum on cardiac functions.

Data sources

Based on aspects of CT, ultrasound cardiography (UCG) and MRI, all the recent literatures on the influence of pectus excavatum on cardiac function were searched and reviewed.

Results

Moderate and severe pectus excavatum did have a negative effect on cardiac function. Cardiac rotation angle, cardiac compression index, right atrial and tricuspid annulus size, septal motion and myocardial strain are relatively effective indexes to evaluate cardiac function.

Conclusions

Pectus excavatum did have a negative effect on cardiac function; so surgeons should actively diagnose and treat such patients in clinical work. However, further research is needed on to explore the measures and indicators that can reflect the changes of cardiac function in patients objectively, accurately, effectively and timely.
Spatial genetic structure in the rock hyrax (Procavia capensis) across the Namaqualand and western Fynbos areas of South Africa — a mitochondrial and microsatellite perspective
Authors: Visser J.H. , Robinson T.J. , Jansen van Vuuren B.
Published: May 2020

The interplay between biotic and abiotic environments is increasingly recognized as a major determinant of spatial genetic patterns. Among spatial genetic studies, saxicolous or rock-dwelling species remain underrepresented in spite of their strict dependence on landscape structure. Here we investigated patterns and processes operating at different spatial (fine and regional scales) and time scales (using mitochondrial and microsatellite markers) in the rock hyrax (Procavia capensis (Pallas, 1766)). Our focus was on the western seaboard of South Africa and included two recognized biodiversity hotspots (Cape Floristic Region and Succulent Karoo). At fine spatial scale, significant genetic structure was present between four rocky outcrops in an isolated population, likely driven by the social system of this species. At a broader spatial scale, ecological dependence on rocky habitat and population-level processes, in conjunction with landscape structure, appeared to be the main drivers of genetic diversity and structure. Large areas devoid of suitable rocky habitat (e.g., the Knersvlakte, Sandveld, and Cape Flats, South Africa) represent barriers to gene flow in the species, although genetic clusters closely follow climatic, geological, and phytogeographic regions, possibly indicating ecological specialization or adaptation as contributing factors enforcing isolation. Taken together, our study highlights the need to consider both intrinsic and extrinsic factors when investigating spatial genetic structures within species.
Simulation of Stacked Quantum Dot Channels SWS-FET Using Multi-FET ABM Modeling
Authors: Salama H. , Saman B. , Gudlavalleti R. H. , Chan P-Y. , Mays R. , Khan B. , Heller E. , Chandy J. , Jain F.
Published: May 2020

This paper presents simulation of spatial wavefunction switched (SWS) field-effect transistors (FETs) comprising of two vertically stacked quantum dot channels. An analog behavior model (ABM) was used to compare the experimental I-V characteristics of a fabricated QD-SWS-FET. Each channel consists of two quantum dot layers and are connected to the dedicated drains D2 and D1, respectively. The fabricated SWS-FET has one source and one gate. The ABM simulation models SWS-FET comprising of two independent conventional BSIM FETs with their (W/L) ratios, capacitances and other device parameters. The agreement in simulation and experimental data will advance modeling of SWS based adders, logic gates and SRAMs.
An improved hybrid lattice Boltzmann flux solver for 3D integrated hypersonic fluid-thermal-structural analysis
Authors: Li Jia-Wei , Wang Jiang-Feng
Published: May 2020

In this paper, a hybrid lattice Boltzmann flux solver (LBFS) is proposed for simulation of 3D integrated hypersonic fluid-thermal-structural problems. In the solver, the macroscopic 3D Navier–Stokes equations and structural heat transfer equation are discretized by the finite volume method and the numerical fluxes at the cell interface are reconstructed by the local solution of Boltzmann equation. To compute the numerical fluxes, two lattice velocity models are introduced. One is the D1Q4 discrete velocity model for calculating the inviscid flux across the cell interface of N–S equations, and the other one is the D3Q6 model for evaluating the flux of structural energy equation. Furthermore, a new dual-thermal-resistance model is proposed to calculate the thermal properties on the fluid-structure interface. To validate the accuracy and stability of the present solver, applications for hypersonic fluid-thermal-structural analysis are demonstrated on aerodynamically heated blunt cone body at [Formula: see text]. Numerical results showed that the present solver can predict accurately the thermal properties of hypersonic fluid-thermal-structural problems and offer the potential for significant improvements in predicting fluid-structural-thermal problems of long-endurance high speed vehicles.
Aerothermal prediction of hypersonic flow around spherical capsule model using IDDES approach
Authors: Li Chen , Guo Qi-Long , Sun Dong , Zhang Han-Xin
Published: May 2020

The prediction of heat transfer for blunt bodies in hypersonic flows remains a great challenge. In particular, the uncertainties are larger in the leeside due to the complexity of the wake flow. Generally, the heat transfer is over-predicted using the Reynolds-averaged Navier–Stokes (RANS) models. In this paper, the improved delayed detached eddy simulation (IDDES) method is used to simulate the Mach 6 flow around a scaled spherical capsule model. In addition, a low dissipative WENO scheme is used for inviscid fluxes and dual-time stepping method is applied for time advancement. Results are compared to experimental data for mean and instantaneous heat transfer in the leeside of the aftbody. It is shown that the integrated error is 75.49% for RANS while 35.69% for IDDES method. Moreover, the multi-scale structures in the separation region are also resolved well by the IDDES method.
An experimental study of water droplets deformation and collision with airfoil
Authors: Li Wen , Miao Bo , Zhu Chun-Ling , Zhao Ning
Published: May 2020

When aircraft pass through the clouds that contain super cooled water droplets during aviation, the droplets collide with the wing surface and ice is formed, which induces a significant threat to aviation safety. Studies on droplet movement in gaseous medium are prerequisite for deicing/anti-icing researches. So, in this work, an experimental study is performed on water droplet deformation as the droplets approach the leading edge of an airfoil. This experiment is carried out in a vertical wind tunnel, with a NACA0012 airfoil model assembled 4.3 m downstream of the droplet generator. The influence of Weber number (ranging from 0.2 to 36) on the deformation of a 2 mm diameter droplet is thoroughly investigated. The results indicate that droplets maintain initial form with Weber number under 10; after that droplet deforms into remarkable bag deformation as Weber number reaches to 19, and bag-stamen deformation mode as Weber number is above 20. This observed correlation between Weber number and deformation mode is validated through comparing with published simulation results. Furthermore, using the high-speed camera, clear images of the droplet structure during the deformation process are taken and are shown in detail in this work.
Wall pressure unsteadiness in an over-expanded single expansion ramp nozzle
Authors: He Chengjun , Li Jianqiang , Fan Zhaolin , Li Yaohua , Liang Jingmin , Miao Lei , Gao Rongzhao
Published: May 2020

To evaluate the unsteady nature of wall pressure in an over-expanded single expansion ramp nozzle, under fixed nozzle pressure ratio (NPR) of 5.92, 6.55 and 7.19, an experimental investigation has been conducted based on focusing Schlieren techniques and dynamic pressure measurement. For all cases, the results show fully formed restricted shock separation (RSS) on the upper wall, which experiences flow reattachment on the wall downstream of separation resulting in the formation of a separation bubble. The separation mode is also RSS on the lower wall at [Formula: see text]. However, the lower wall pressure is randomly larger or lower than ambient pressure near the nozzle exit at [Formula: see text], the separated shear-layer can intermittently impinge on the lower wall, and the separation mode is partially restricted shock separation (pRSS). At [Formula: see text], the separation flow does not reattach downstream of the lower wall. That is, it occurs free shock separation (FSS).
Influence of PECVD-TiO2 film morphology and topography on the spectroscopic ellipsometry data fitting process
Authors: Li Dayu , Zhang Wentao , Goullet A.
Published: May 2020

TiO2 films of different thickness are deposited on silicon substrate at low temperature and pressure by a Helicon-PECVD reactor. The evolution of film morphology and topography is observed by scanning electron microscopy (SEM) and atomic force microscopy (AFM), meanwhile the spectroscopic ellipsometry (SE) measurements are performed to investigate the film growth mechanism and optical constants. The SEM and AFM observations show that all the films exhibit a columnar structure, moreover all the columns are vertical grown and well-organized when the thickness below [Formula: see text][Formula: see text]80 nm. As the thickness is increased to [Formula: see text][Formula: see text]150 nm, 250 nm and 450 nm, the column size is increased in the top layers, the whole film morphology becomes inhomogeneous, which leads to a decreased density and rougher surface. By fitting the SE measurements, a suitable gradient physical model is found to describe the film morphologies, the model consists of a native SiO2 layer on Si substrate, a mediate layer mixed TiO2 with void whose concentration gradient changed from bottom to top, and a top roughness layer. For thick films ([Formula: see text][Formula: see text]450 nm), the absorption and scattering on the rough surface is considered in order to keep the precision of SE fits. It is found that the optical index is decreased with film thickness, which is related to the evolution of structure in the top layers.
Structural, morphological and magnetic properties of Ni–Cu–Co ferrites by the Sm3+ ions substitution
Authors: Yu Lichao , Sun Aimin , Suo Nanzhaxi , Zuo Zhuo , Zhao Xiqian , Zhang Wei
Published: May 2020

In this experiment, samarium ion was doping into nickel–copper–cobalt ferrite system by sol–gel self-propagation. The prepared chemical formula is [Formula: see text]-[Formula: see text] ([Formula: see text], 0.025, 0.05, 0.075 and 0.1). The X-ray diffraction (XRD) analysis of the samples confirms the formation of a cubic spinel structure. The average crystallite sizes are about 66–88 nm for all the prepared samples. Fourier transform infrared spectroscopy (FTIR) measurements showed all the prepared samples had Fe–O absorption peaks. This finding further confirms that the prepared sample has a spinel structure. The morphological changes of the samples were characterized by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). According to the characterization results, the surface morphology shows spherical grains. Energy-dispersive X-ray spectroscopy (EDX) test results showed that the as-prepared pure samples contained Ni, Cu, Co, Fe elements, whereas other samples contained Sm elements and the contents were different. This indicates that the prepared samples are purer and the doping amount has been increased. The magnetic parameters of samples were measured by vibration sample magnetometer (VSM) at room temperature. The analysis of magnetic parameters shows that the saturation magnetization [Formula: see text] and remanent magnetization [Formula: see text] of the sample decrease with the increase of the doping amount of samarium ions. From the magnetic parameters, it can be concluded that [Formula: see text]-doped Ni–Cu–Co ferrites have low magnetic properties.
Trade-offs between Distributed Ledger Technology Characteristics
Authors: Kannengießer Niclas , Lins Sebastian , Dehling Tobias , Sunyaev Ali
Published: May 2020

When developing peer-to-peer applications on distributed ledger technology (DLT), a crucial decision is the selection of a suitable DLT design (e.g., Ethereum), because it is hard to change the underlying DLT design post hoc. To facilitate the selection of suitable DLT designs, we review DLT characteristics and identify trade-offs between them. Furthermore, we assess how DLT designs account for these trade-offs and we develop archetypes for DLT designs that cater to specific requirements of applications on DLT. The main purpose of our article is to introduce scientific and practical audiences to the intricacies of DLT designs and to support development of viable applications on DLT.
Incomplete Network Alignment
Authors: Zhang Si , Tong Hanghang , Tang Jie , Xu Jiejun , Fan Wei
Published: May 2020

Networks are prevalent in many areas and are often collected from multiple sources. However, due to the veracity characteristics, more often than not, networks are incomplete. Network alignment and network completion have become two fundamental cornerstones behind a wealth of high-impact graph mining applications. The state-of-the-art have been addressing these two tasks
in parallel
. That is, most of the existing network alignment methods have implicitly assumed that the topology of the input networks for alignment are perfectly known a priori, whereas the existing network completion methods admit either a single network (i.e., matrix completion) or multiple aligned networks (e.g., tensor completion). In this article, we argue that network alignment and completion are inherently complementary with each other, and hence propose to jointly address them so that the two tasks can mutually benefit from each other. We formulate the problem from the optimization perspective, and propose an effective algorithm (
iNeAt
) to solve it. The proposed method offers two distinctive advantages. First (
Alignment accuracy
), our method benefits from the higher-quality input networks while mitigates the effect of the incorrectly inferred links introduced by the completion task itself. Second (
Alignment efficiency
), thanks to the low-rank structure of the complete networks and the alignment matrix, the alignment process can be significantly accelerated. We perform extensive experiments which show that (1) the network completion can significantly improve the alignment accuracy, i.e., up to 30% over the baseline methods; (2) the network alignment can in turn help recover more missing edges than the baseline methods; and (3) our method achieves a good balance between the running time and the accuracy, and scales with a provable
linear
complexity in both time and space.
Dynamic Precision Autotuning with TAFFO
Authors: Cherubin Stefano , Cattaneo Daniele , Chiari Michele , Agosta Giovanni
Published: May 2020

Many classes of applications, both in the embedded and high performance domains, can trade off the accuracy of the computed results for computation performance. One way to achieve such a trade-off is precision tuning—that is, to modify the data types used for the computation by reducing the bit width, or by changing the representation from floating point to fixed point. We present a methodology for high-accuracy dynamic precision tuning based on the identification of input classes (i.e., classes of input datasets that benefit from similar optimizations). When a new input region is detected, the application kernels are re-compiled on the fly with the appropriate selection of parameters. In this way, we obtain a continuous optimization approach that enables the exploitation of the reduced precision computation while progressively exploring the solution space, thus reducing the time required by compilation overheads. We provide tools to support the automation of the runtime part of the solution, leaving to the user only the task of identifying the input classes. Our approach provides a significant performance boost (up to 320%) on the typical approximate computing benchmarks, without meaningfully affecting the accuracy of the result, since the error remains always below 3%.
Large Coseismic Slip to the Trench During the 2011 Tohoku-Oki Earthquake
Authors: Kodaira Shuichi , Fujiwara Toshiya , Fujie Gou , Nakamura Yasuyuki , Kanamatsu Toshiya
Published: May 2020

The strong ground motions, large crustal deformation, and tsunami generated by the 2011 Tohoku-oki earthquake ( Mw 9.1) reveal that a large coseismic slip likely propagated to shallow depth in the Japan Trench. Although data acquired by onshore networks cannot resolve the slip behavior of the updip fault rupture, marine geophysical and geological studies provide direct evidence of coseismic slip to the trench. Differential bathymetry data show ∼50 m of coseismic seafloor displacement extending to the central Japan Trench (38–39.2°N). Seismic data show that coseismic slip ruptured the seafloor within the trench. Pelagic clays may have promoted slip propagation to shallow depths, whereas disturbed/metamorphosed clays may have restricted slip to the main rupture zone. Those observations imply that a smooth, broadly distributed, weak, clay-rich sediment in a shallow part of a subduction zone is a characteristic factor that can foster a large coseismic slip to the trench and, consequently, the generation of a large tsunami. ▪  During the 2011 Tohoku-oki earthquake ( Mw 9.1), more than ∼50 m of slip occurred on a fault that ruptured the seafloor in the central Japan Trench. ▪  The fault rupture reaching the seafloor caused a large tsunami. ▪  Marine geophysical explorations revealed that a clay-rich sediment in the subduction zone was one factor fostering the large fault slip. ▪  Understanding of slip behavior in the shallow portion of a subduction zone will help us prepare for future large tsunamis along the Japan-Kuril Trench.
FLOT Neoadjuvant Chemotherapy Followed by Laparoscopic D2 Gastrectomy in the Treatment of Locally Resectable Advanced Gastric Cancer
Authors: Zhang Shun , Yan Dongyi , Sun Qi , Du Tao , Cao Dongliang , Yang Yao , Yuan Biao , Li Haiqiang , Jiang Xiaohua , Song Chun
Published: May 2020

Background. The prognosis of patients with advanced gastric cancer remains unsatisfactory, highlighting the need for improved therapeutic strategies. We analyzed 23 resectable advanced gastric cancer patients who received FLOT followed by laparoscopic gastrectomy with D2 lymphadenectomy to evaluate the efficacy and safety. Methods. Patients aged 18–75 years with gastric adenocarcinoma (stage cT3–4 and/or N + M0) underwent neoadjuvant FLOT therapy (four preoperative and four postoperative 2-week cycles) at Shanghai East Hospital. Laparoscopic gastrectomy was scheduled 3-4 weeks after completion of the last cycle of preoperative chemotherapy. The type of surgical procedure was determined by the location and extent of the primary tumor. Results. 23 patients were reviewed in the study. 20 patients (81.2%) received four courses of FOLT therapy, while 3 patients (18.8%) received three courses of treatment. There were 3 (13.0%) complete responses, 13 (56.5%) partial responses, 4 (26.1%) of stable disease, and 1 (4.3%) of progressive disease. The clinical efficacy response rate was 69.6%. The R0 resection rate was 91.3%. Only one patient exhibited grade III postoperative complications. The pathologic complete remission was 13%. The common grade 3/4 adverse events from chemotherapy were leucopenia (17.4%), neutropenia (30.4%), anemia (13%), anorexia (13%), and nausea (17.4%). Postoperative complications occurred in 5 patients (26.1%). There was no treatment-related mortality or reoperation. The most reason for not completing chemotherapy was the patient’s request. Conclusions. These findings suggest that FLOT neoadjuvant chemotherapy, followed by laparoscopic D2 gastrectomy, is effective and safe in advanced, resectable advanced gastric cancer.
Line Spectrum Chaotification on QZS Systems with Time-Delay Control
Authors: Zhang Jing , Tang Tao , Fang Wenhua
Published: May 2020

Chaotification can be employed to weaken or eliminate the feature of line spectra of waterborne noise. The efficiency of this method lies on the use of small control. The analysis reveals that the critical control gain depends on the stiffness of vibration isolation systems. Thus, an isolation raft system based on quasi-zero-stiffness (QZS) property is proposed for line spectrum chaotification. A nonlinear time-delay controller is derived accordingly. Comparative analysis shows that the new approach allows much smaller control, and the intensity of line spectra is further reduced. Numerical simulations also indicate other advantages with the introduction of QZS system into chaotification.