bluuebunny/crossref_metadata_2025 huggingface dataset:
Public Perception on Attributes of Walking Avenues in Urban Areas of Sri Lanka
Authors: Wickramaarachchi Nishani , Perera Tharanee , Jalenthi Lekamlage Dilhan
Published: January 2022

Currently, the urban areas become more congested; numerous health concerns such as obesity are becoming more prevalent among urban dwellers followed by lack of exercise. With this situation, provision of adequate areas for exercising to the satisfaction of all is critical with limited space in urban areas. Hence, an ideal solution emerges as ‘walking ways’ where a strip of land is only needed. The interest of walking ways is also developed in Sri Lanka very recently. However, there is no evidence on a research to identify the attributes, should developed along with the walkway to increase the attraction of the users. The main aim of this study is to examine the public perception on attributes of walking avenues in urban areas of Sri Lanka. Data was acquired by a personal-administered questionnaire from a convenience sample of 150 walking trail users on three settings. The descriptive statistics, univariate analysis, hoc multiple comparisons and homogeneous subsets technique were used as methodological analysis. The findings disclose ‘safety’ as the preferred attribute while shading and natural settings significant. An income variation presents that user with above the income level of LKR 65,000 preferred cafeterias providing herbal drinks while the users with below that income level are less interest with the attributes of changing rooms and street vendors. This article fills the gap of identifying user perceptions particular to a novel design concept of walking trail in Sri Lanka with interesting attributes getting more benefits.
Mathematical Method to Assess the Yin-Yang Balance of Commercial Complexes’ Entrances
Authors: Zhang Yucheng , So Albert , Ge Xin Janet
Published: January 2022

Shopping malls are important landmarks of modern and sustainable cities as they are substantial business and investment by themselves, and as they also facilitate the social activities of communities. Entrances to shopping malls provide a first impression to customers, thus affecting the business performance of the malls. This paper presents a method to assess the entrances of modern shopping malls by applying traditionally qualitative Feng shui practices quantitatively with an innovative mathematical model. The assessment is based on the manipulation of the yin-and-yang concept applied to the layout of Ming tang (bright court) as the focus of consideration. By applying this novel approach to three shopping malls in Guangzhou, China as a pilot study to match their commercial performance, our hypothesis appears workable. The ideology of balancing yin and yang may be practically meaningful to urban planning and the successful measurement of such balance could shed light on future studies.
Modeling and Simulation of an Assistive Exoskeleton Leg System With Knee Osteoarthritis and Quadriceps Weakness
Authors: Iscan Mehmet , Yilmaz Cuneyt , Vural Berkem , Eken Huseyin
Published: January 2022

The most common human locomotion problems such as quadriceps weakness, knee osteoarthritis can be healed up by using exoskeleton mechanisms with proper control systems. However, these kinds of abnormalities cannot be easily modeled in terms of engineering perspectives due to a lack of adequate data or unknown dynamics. Also, nature always seeks minimum energy as well as biology, which means that the unknown dynamics can be built by using this phenomenon. In this study, a new system dynamic model had been involved in designing a simple single-legged exoskeleton robot mechanism and its control system to assist partially disabled individuals to improve their quality of locomotion. To determine the specific features of the human gait disorders to interpret their nature in the computer-aided simulation environment, knee osteoarthritis, and quadriceps weakness, which are the common types of such problems, have been chosen as the main interests for this study. By using the lower limb model with anthropometric data, the simulations of disorders have been realized on matlabsimscape environment, which enables us to model the entire exoskeleton system with the three-dimensional parts of the human body. A model of a leg with the disorder was able to be obtained with the utilization of feedback linearization, which is one of the examples of minimum principles in the control theory. A proper gait cycle is achieved with the exoskeleton application and separately for the leg, with approximately 10 deg deviation from the natural property in knee flexion. Finally, it can be seen that the system conversion into such problematic cases with or without an exoskeleton system is accomplished.
Numerical Study of Unsteady Cavitating Flow in an Inducer With Omega Vortex Identification
Authors: Yan Longlong , Gao Bo , Ni Dan , Zhang Ning , Zhou Wenjie
Published: January 2022

To accurately capture the behaviors of cavitation and reveal the unsteady cavitating flow mechanism, a condensate pump inducer is numerically analyzed in a separate numerical experiment with large eddy simulation (LES) at critical cavitation number σind,c under the design point. Based on the new Omega vortex identification method, the correlation between the flow structures and cavities is clearly illustrated. Besides, the pressure fluctuations around the inducer are analyzed. Special emphasis is put on the analysis of the interactions between the cavities, turbulent fluctuations, and vortical flow structures. The Omega vortex identification method could give an overall picture of the whole cavitating flow structures to present a clear correlation between the vortices and cavities. The results show that the shear cavitation dominates the cavitation characteristics under the design point. The pure rigid rotation region mainly concentrates at the edge of the cavities while the other sheet-like cavities near the casing walls are characterized by strong turbulence fluctuations. Besides, based on the analysis of the correlation between the cavities and flow structures, the rotating cavitation under the design point may mainly be attributed to the interaction between the tip leakage vortex cavitation and the next blade.
Flow Characteristics of Gerotor Motors With Pin and Nonpin Designs
Authors: Hsieh Chiu-Fan , Johar Tehseen , Lin Yi-Hao
Published: January 2022

The geometric design of a gerotor motor has a significant impact on its function, performance, quality, reliability and cost. When designing a gerotor motor all these features must be considered. A gerotor motor can be classified into two types based on the geometric design; gerolor (pin design) and gerotor (nonpin design). In this article, geometric parameters of the two design types are discussed briefly and the operation of the gerotor motor is described as well. A numerical analysis is carried out by using computational fluid dynamics (CFD) tool (PumpLinx) to analyze the fluid flow and predict the performance of both types of gerotor designs. Various characteristics of the two designs of the gerotor motor are investigated and compared which include the gerotor design, fluid flowrate, velocity, pressure and output torque. Comparison of the results found out that using pin design gerotor motor, the flowrate, flow velocity, pressure and torque will vary greatly. Nonpin design can significantly reduce variations in all the flow characteristics thereby enhancing the stability and reduction in the leakage risk.
Friction Factor Comparison Between Mixing Length Theory and Empirical Correlation
Authors: Prasad Mahendra
Published: January 2022

Equivalent sand grain roughness is required for estimating friction factor for engineering applications from empirical relation via Haalands equation. The real surfaces are different from the sand grain profile. The correlations for friction factor were derived from the use of discrete roughness elements with regular shapes such as cones and bars. The purpose of the paper is to derive the analytical expression of friction factor for a two-dimensional (2D) semicylindrical roughness (not exactly a three-dimensional (3D) sand grain but for the circular profile of cross-section) using Navier–Stokes equation and mixing length theory. This is compared with the modified series mathematical representation of Haalands equation for friction factor in terms of equivalent sand grain roughness. The comparison is valid for a high Reynolds number where the velocity profile is almost flat beyond the boundary layer and approximately linear all throughout the boundary layer. The high Reynolds number approximation for Haalands equation is derived and the series form of the friction factor compares approximately with the series form derived from first principles, where in the exponents of the series expansion are close.
Estimation of Turbulent Length Scales at a Turbocharger Inlet Using Stereoscopic Particle Image Velocimetry
Authors: Banerjee Deb , Selamet Ahmet , Dehner Rick
Published: January 2022

Stereoscopic particle image velocimetry (SPIV) measurements are carried out at the inlet of a turbocharger compressor at four different shaft speeds from 80,000 rpm to 140,000 rpm and over the entire range of flow rates from choke to mild surge. This paper describes the procedure used in processing the SPIV data leading to the estimates of turbulent length scales—integral, Taylor, and Kolmogorov, to enhance the fundamental understanding and characterization of the compressor inlet flow field. The analysis reveals that at most operating conditions, the three different length scales have markedly different magnitudes, as expected, while they have somewhat similar qualitative distributions with respect to the duct radius. For example, at 80,000 rpm and at a flowrate of 15.7 g/s (mild surge), the longitudinal integral length scale is of the order of 15 mm, the Taylor scale is around 0.5 mm, and the Kolmogorov scale is about 10 μm. With the onset of flow reversal, the turbulent kinetic energy and turbulent intensity at the compressor inlet are observed to increase rapidly, while the magnitudes of the Kolmogorov scale and to a certain extent, the Taylor scale are found to decrease suggesting that the increased turbulence gives rise to even smaller flow structures. The variation of length scales with compressor shaft speed has also been studied.
A Circular Eccentric Vibration Absorber With Circumferentially Graded Acoustic Black Hole Features
Authors: Ji Hongli , Zhao Xiaoning , Wang Ning , Huang Wei , Qiu Jinhao , Cheng Li
Published: January 2022

A previously proposed planar axisymmetric dynamic vibration absorber (DVA), with embedded acoustic black hole (ABH) features, has been shown to suffer from the very selective coupling with the host structure, thus compromising its vibration reduction performance. To tackle the problem, an eccentric ABH-based circular DVA whose thickness profile is tailored according to a circumferential gradient variation is proposed. This new configuration preserves the ABH profile in the radial direction and breaks the axisymmetric of the original DVA design at the same time. While the former permits the ABH features to fully play out in a continuous manner, the later entails a more effective coupling with the host structure. These salient properties have been demonstrated and confirmed both numerically and experimentally by examining a benchmark plate structure. For analyses, a coupling model embracing the host structure and the add-on DVAs is established which allows the calculation of the coupling coefficient, a vital quantity to guide the DVA design. Studies demonstrate the advantages of the proposed DVA over existing designs for the same given mass. The enriched structural coupling and the enhanced modal damping, arising from the eccentric and circumferentially graded ABH design, are shown to be the origin of such improvement. All in all, the physical process underpinning the dynamic absorber principle and waveguide absorber from the host structures is simultaneously consolidated, thus leading to superior broadband structural vibration suppression.
Hybrid Mass Damper: Theoretical and Experimental Power Flow Analysis
Authors: Billon K. , Zhao G. , Collette C. , Chesné S.
Published: January 2022

In this paper, a hybrid mass damper (HMD) and its hyperstability due to a power flow approach are studied. The HMD proposed combines an active control system with an optimal passive device. The initial passive system is an electromagnetic tuned mass damper (TMD) and the control law is a modified velocity feedback with a phase compensator. The resulting hybrid controller system is theoretically hyperstable and ensures fail-safe behavior. Experiments are performed to validate the numerical simulation and provide good results in terms of vibration attenuations. Both excitation from the bottom in the frequency domain and shock response in the time domain are tested and analyzed. The different power flows in terms of active and reactive powers are estimated numerically and experimentally on the inertial damper (passive and active) and on the HMD. Moreover, through a mechanical analogy of the proposed system, it is shown that this hybrid device can be seen as an active realization of an inerter based tuned-mass-damper associated with a sky-hook damper. Observations and analysis provide insight into the hyperstable behavior imposed by the specific control law.
Experimental and Numerical Study of Heat Transfer and Pressure Loss in a Swirl Multi-Pass Channel With Convergent Jet Slots
Authors: Luan Yong , Rao Yu , Wang Kai , Wu Weilong
Published: January 2022

This paper presents a comparative experimental and numerical study of the heat transfer and pressure loss in a swirl multi-pass channel with tangential jet slots, and another baseline multi-pass channel with 180-deg U-bends as a comparison baseline has also been investigated. The tangential jets can induce large-scale swirling flows and significantly enhance the connective heat transfer. The swirl multi-pass channel can be considered as an effective internal cooling strategy for the gas turbine blades. Transient liquid crystal thermography is used to obtain the detailed heat transfer distribution on the internal surfaces of the multi-pass serpentine channels. The heat transfer patterns in the swirl multi-pass channel are quite different from those of the baseline multi-pass channel. Circumferentially, the three heat transfer surfaces, i.e., the bottom, top and side surfaces of the two multi-pass serpentine channels, have roughly similar trend along the flow direction and reach the peak values after the U-bends and jet injections, respectively. Compared with the baseline multi-pass channel, the experimental globally averaged Nusselt number ratios of the last two passes in the swirl multi-pass channel can be increased by up to 82.9%, 104.8%, and 124.6% for the Reynolds numbers 20,000, 40,000, and 60,000, respectively. The differences of globally averaged Nusselt number ratios between the two kinds of multi-pass serpentine channels gradually increase with the Reynolds numbers, which means that the swirl multi-pass channel has higher heat transfer enhancement capability at a higher Reynolds number. The circumferentially uniform heat transfer characteristic of swirling flow also performs well in this study. The high and circumferentially uniform heat transfer is mainly due to the large-scale swirling flow induced by the tangential slots. In more detail, the large-scale swirling flow impinges onto the surface and further induces high tangential velocity near the wall, which destroys the boundary layer flow and thus improves the heat transfer rates at the wall. However, the notable pressure loss of the swirl multi-pass channel should be further controlled reasonably, which is about 5.4 times that of the baseline multi-pass channel. As supplements to the experiments, three-dimensional numerical computations provide more insights into the turbulent flow structure in the two kinds of multi-pass serpentine channels.
Calibration of a Computational Fluid Dynamics Methodology for the Simulation of Roughness Effects on Friction and Heat Transfer in Additive Manufactured Components
Authors: Mazzei Lorenzo , Da Soghe Riccardo , Bianchini Cosimo
Published: January 2022

It is well known from the literature that surface roughness significantly affects friction and heat transfer. This is even more evident for additive manufactured (AM) components, which are taking an increasingly important role in the gas turbine field. However, the exploitation of numerical approaches to improve their design is hindered by the lack of dedicated correlations and computational fluid dynamics (CFD) models developed for such high roughness conditions. Usually, the AM components are simulated considering the surfaces as smooth or applying an equivalent sand-grain roughness (ks) that results in a velocity shift in the boundary layer. However, determining a priori the most appropriate value of ks is challenging, as dozens of correlations are available, returning scattered and uncertain results. A previous work proved how the CFD prediction of friction and heat transfer returns significant deviations, even exploiting the ks values obtained from experimental tests on the very same test case. That work also allowed identification of a promising CFD methodology based on friction and thermal corrections proposed by Aupoix from ONERA. The aim of this work is to further the assessment and calibration activity of the model, by analyzing additional experimental data of friction factor and Nusselt number from new test cases considering different geometries and flow conditions. The new coupons consisted of straight circular channels and wavy channels. This work represents a further step in the generation of a more validated and general methodology for the high-fidelity CFD analysis of AM components.
Micro-Structural Design of Soft Solid Composite Electrolytes With Enhanced Ionic Conductivity
Authors: Khodabandehloo Nastaran , Mozaffari Kosar , Liu Liping , Sharma Pradeep
Published: January 2022

Electrolyte in a rechargeable Li-ion battery plays a critical role in determining its capacity and efficiency. While the typically used electrolytes in Li-ion batteries are liquid, soft solid electrolytes are being increasingly explored as an alternative due to their advantages in terms of increased stability, safety and potential applications in the context of flexible and stretchable electronics. However, ionic conductivity of solid polymer electrolytes is significantly lower compared to liquid electrolytes. In a recent work, we developed a theoretical framework to model the coupled deformation, electrostatics and diffusion in heterogeneous electrolytes and also established a simple homogenization approach for the design of microstructures to enhance ionic conductivity of composite solid electrolytes. Guided by the insights from the theoretical framework, in this paper, we examine specific microstructures that can potentially yield significant improvement in the effective ionic conductivity. We numerically implement our theory in the open source general purpose finite element package FEniCS to solve the governing equations and present numerical solutions and insights on the effect of microstructure on the enhancement of ionic conductivity. Specifically, we investigate the effect of shape by considering ellipsoidal inclusions. We also propose an easily manufacturable microstructure that increases the ionic conductivity of the composite electrolyte by 40 times, simply by the addition of dielectric columns parallel to the solid electrolyte phase.
Integrating ultrasound education and resources within undergraduate medical education in order to Bring Ultrasound Internationally for Long-term Development (BUILD)
Authors: Prats Michael I. , Boone Kirsten Irene , Gorgas Diane , Bahner David
Published: January 2022

Aims: At the Ohio State University College of Medicine, medical students have the option to train in ultrasound and take part in global electives where they can utilize clinical ultrasound. This presents the opportunity for medical students to engage in bidirectional sharing of medical and ultrasound knowledge in geographic regions with limited resources. We developedBringing Ultrasound Internationally for Long-term development (BUILD), a longitudinal course, to provide standardized ultrasound education to students planning to enroll in global health electives.Material and methods: This was a pilot study of the BUILD curriculum. Third-year medical students planning to complete a global health elective were invited to participate. Enrolled students completed an online curriculum, hands-on scanning, and pathology sessions, which augmented the predeparture Global Health course work. Students received two resource assessments: one to be completed by the student, and one to be completed by the on-site preceptor. Main outcomes measured were number of enrolled students, primary indications for imaging, and number of scans per-day.Results: In total, 152 students participated in the study and traveled to 22 different global sites in Low-Income Countries (LIC’s). All enrolled students completed the curriculum. Between 3 and 25 scans were performed per day and the leading indication for ultrasound imaging was obstetric and abdominal pain evaluation.Conclusions: The BUILD curriculum is a feasible construct to prepare students for using ultrasound during global electives. Students successfully performed proctored scans in a variety of settings. This format can be adopted by other institutions to further support student and global ultrasound programs.
Adjustment of fecundity and sex ratio in response to social environments in a haplodiploid mite
Authors: Weerawansha Nuwan , Wang Qiao , He Xiong Zhao
Published: January 2022

Animals can adjust reproductive strategies in favour of corporation or competition in response to local population size and density, the two key factors of social environments. However, previous studies usually focus on either population size or density but ignore their interactions. Using a haplodiploid spider mite, Tetranychus ludeni Zacher, we carried out a factorial experiment in the laboratory to examine how ovipositing females adjust their fecundity and offspring sex ratio during their early reproductive life under various population size and density. We reveal that females laid significantly more eggs with increasing population size and significantly fewer eggs with increasing population density. This suggests that large populations favour cooperation between individuals and dense populations increase competition. We demonstrate a significant negative interaction of population size and density that resulted in significantly fewer eggs laid in the large and dense populations. Furthermore, we show that females significantly skewed the offspring sex ratio towards female-biased in small populations to reduce the local mate competition among their sons. However, population density incurred no significant impact on offspring sex ratio, while the significant positive interaction of population size and density significantly increased the proportion of female offspring in the large and dense populations, which will minimise food or space competition as females usually disperse after mating at crowded conditions. These results also suggest that population density affecting sex allocation in T. ludeni is intercorrelated with population size. This study provides evidence that animals can manipulate their reproductive output and adjust offspring sex ratio in response to various social environments, and the interactions of different socio-environmental factors may play significant roles.
Emergent phenomena at oxide interfaces studied with standing-wave photoelectron spectroscopy
Authors: Kuo Cheng-Tai , Conti Giuseppina , Rault Julien E. , Schneider Claus M. , Nemšák Slavomír , Gray Alexander X.
Published: January 2022

Emergent phenomena at complex-oxide interfaces have become a vibrant field of study in the past two decades due to the rich physics and a wide range of possibilities for creating new states of matter and novel functionalities for potential devices. The electronic-structural characterization of such phenomena presents a unique challenge due to the lack of direct yet nondestructive techniques for probing buried layers and interfaces with the required Ångstrom-level resolution, as well as element and orbital specificity. In this Review, we survey several recent studies wherein soft x-ray standing-wave photoelectron spectroscopy—a relatively newly developed technique—is used to investigate buried oxide interfaces exhibiting emergent phenomena such as metal-insulator transition, interfacial ferromagnetism, and two-dimensional electron gas. The advantages, challenges, and future applications of this methodology are also discussed.
Reaction mechanism studies on atomic layer deposition process of AlF3
Authors: Nieminen Heta-Elisa , Ritala Mikko
Published: January 2022

In this work, the reaction mechanism in the atomic layer deposition (ALD) process of AlF3 thin films is studied with in situ quartz crystal microbalance and quadrupole mass spectrometer. The depositions are done with AlCl3 and TiF4 as precursors. Similar to many metal fluoride films deposited by ALD, the growth rate of the AlF3 is strongly temperature dependent. In addition, at low temperatures, the growth rate is exceptionally high for a traditional ALD process. In this study, the reasons behind these characteristics are studied and a detailed step-by-step mechanism for the AlF3 film growth process is presented.
Design and characterization of a three-dimensional anisotropic additively manufactured pentamode material
Authors: Cushing Colby W. , Kelsten Matthew J. , Su Xiaoshi , Wilson Preston S. , Haberman Michael R. , Norris Andrew N.
Published: January 2022

A metamaterial of particular interest for underwater applications is the three-dimensional (3D) anisotropic pentamode (PM), i.e., a structure designed to support a single longitudinal wave with a sound speed that depends on the propagation direction. The present work attempts to experimentally verify anisotropic sound speeds predicted by finite element simulations using additively manufactured anisotropic 3D PM samples made of titanium. The samples were suspended in front of a plane wave source emitting a broadband chirp in a water tank to measure time of flight for wavefronts with and without the PM present. The measurement utilizes a deconvolution method that extracts the band limited impulse response of data gathered by a scanning hydrophone in a plane of constant depth behind the samples. Supporting material takes the form of finite element simulations developed to model the response of a semi-infinite PM medium to an incident normal plane wave. A technique to extract the longitudinal PM wave speed for frequency domain simulations based on Fourier series expansions is given.
Effects of Soccer Exercise on Balance Ability and Kinesthesia of the Lower Limb Joints in Children Aged 5–6 Years
Authors: Shen Kebin , Liu Yunxi
Published: January 2022

Age-, height- and weight-matched children were recruited to the experimental group (EG; n = 31) and control group (n = 32). Following a 16-week soccer training program, balance ability and dominant-side lateral knee and ankle kinesthesia changes were tested. Regarding balance ability, the Sway Index, when children stood on a firm or foam surface with their eyes closed in the static balance test, and the dynamic balance test time were 13.5%, 11.6%, and 14.3% lower in the EG than in the control group, respectively. The scores in the left and right directions were 23.7% and 24.2% higher in the EG, respectively. Regarding kinesthesia, the angle of knee extension and ankle metatarsal flexion and dorsiflexion were 13.4%, 20.0%, and 16.8% lower in the EG than in the control group. These results indicate children in the EG had a better performance. After soccer exercise, children aged 5–6 years displayed improved balance in the left and right directions and improved knee extension, ankle plantarflexion, and dorsiflexion kinesthesia.
Treatment, Clinical Outcomes, and Predictors of Mortality among a National Cohort of Admitted Patients with
Acinetobacter baumannii
Infection
Authors: Appaneal Haley J. , Lopes Vrishali V. , LaPlante Kerry L. , Caffrey Aisling R.
Published: January 2022

The objectives were to analyze treatment, clinical outcomes, and predictors of mortality in hospitalized patients with
Acinetobacter baumannii
infection. This was a retrospective cohort study of inpatients with
A. baumannii
cultures and treatment from 2010 to 2019.
Antifungal Resistance Trends of Candida auris Clinical Isolates in New York and New Jersey from 2016 to 2020
Authors: Kilburn Shannon , Innes Gabriel , Quinn Monica , Southwick Karen , Ostrowsky Belinda , Greenko Jane A. , Lutterloh Emily , Greeley Rebecca , Magleby Reed , Chaturvedi Vishnu , Chaturvedi Sudha
Published: January 2022

About 55% of U.S.
Candida auris
clinical cases were reported from New York and New Jersey from 2016 through 2020. Nearly all New York-New Jersey clinical isolates (99.8%) were fluconazole resistant, and 50% were amphotericin B resistant. Echinocandin resistance increased from 0% to 4% and pan-resistance increased from 0 to <1% for New York
C. auris
clinical isolates but not for New Jersey, highlighting the regional differences.
A Novel Plasmid Entry Exclusion System in pKPC_UVA01, a Promiscuous Conjugative Plasmid Carrying the
bla
KPC
Carbapenemase Gene
Authors: Kamruzzaman Muhammad , Mathers Amy J. , Iredell Jonathan R.
Published: January 2022

Conjugative plasmids are the principal mediator in the emergence and spread of antibiotic resistance genes in Enterobacterales. Plasmid entry exclusion (EEX) systems can restrict their transfer into the recipient bacteria carrying closely related plasmids.
Structural Insights into Dihydroxylation of Terephthalate, a Product of Polyethylene Terephthalate Degradation
Authors: Mahto Jai Krishna , Neetu Neetu , Sharma Monica , Dubey Monika , Vellanki Bhanu Prakash , Kumar Pravindra
Published: January 2022

Global plastic pollution has become the most pressing environmental issue. Recent studies on enzymes depolymerizing polyethylene terephthalate plastic into terephthalate (TPA) show some potential for tackling this.
Exercise medicine and physical activity promotion: core curricula for US medical schools, residencies and sports medicine fellowships: developed by the American Medical Society for Sports Medicine and endorsed by the Canadian Academy of Sport and Exercise Medicine
Authors: Asif Irfan , Thornton Jane S , Carek Stephen , Miles Christopher , Nayak Melissa , Novak Melissa , Stovak Mark , Zaremski Jason L , Drezner Jonathan
Published: January 2022

Regular physical activity provides a variety of health benefits and is proven to treat and prevent several non-communicable diseases. Specifically, physical activity enhances muscular and osseous strength, improves cardiorespiratory fitness, and reduces the risk of hypertension, coronary heart disease, stroke, type 2 diabetes, mental health disorders, cognitive decline and several cancers. Despite these well-known benefits, physical activity promotion in clinical practice is underused due to insufficient training during medical education. Medical trainees in the USA receive relatively few hours of instruction in sports and exercise medicine (SEM). One reason for this shortage of instruction is a lack of curricular resources at each level of medical education. To address this need, the American Medical Society for Sports Medicine (AMSSM) assembled a group of SEM experts to develop curricular guidance for exercise medicine and physical activity promotion at the medical school, residency and sports medicine fellowship levels of training. After an evidence review of existing curricular examples, we performed a modified Delphi process to create curricula for medical students, residents and sports medicine fellows. Three training level-specific curricula emerged, each containing Domains, General Learning Areas, and Specific Learning Areas; options for additional training and suggestions for assessment and evaluation were also provided. Review and comment on the initial curricula were conducted by three groups: a second set of experts in exercise medicine and physical activity promotion, sports medicine fellowship directors representing a variety of fellowship settings and the AMSSM Board of Directors. The final curricula for each training level were prepared based on input from the review groups. We believe enhanced medical education will enable clinicians to better integrate exercise medicine and physical activity promotion in their clinical practice and result in healthier, more physically active patients.
THE GENERAL OWNERSHIP STRUCTURE OF THE EUROPEAN AEROSPACE INDUSTRY A STATISTICAL AND NETWORK ANALYSIS
Authors: BIGGIERO LUCIO , MAGNUSZEWSKI ROBERT
Published: January 2022

In this paper, we investigate the ownership structure of the 3143 EU28 aerospace companies in 2019, and extend the analysis to the 2428 neighbor partners outside EU28 and/or aerospace. Different from the previous studies, we consider all equity capital flows regardless of their size, and their monetary value instead of the corresponding ownership share. We further innovate by applying new methods to measure degree of influence power and hierarchical structure. The resulting picture shows that between the pure EU28 aerospace companies: (i) ownership relationships concern only relatively few companies (10%), which trigger horizontal and vertical structures; (ii) density is extremely low; (iii) relationships are fully hierarchical with no cross-ownership; (iv) capital is seldom transferred across business groups; (v) most of the main topological parameters have a typically polarized scale-free structure. When including also the ownership neighbors, some of those traits change substantially: (i) the share of connected companies substantially grows up to 63%; (ii) size and length of the largest pyramidal structures will grow remarkably, reaching a top of 874 companies; (iii) the industry becomes a full small-world structure, thus allowing huge capital transfer across business groups. Finally, a dramatic financialization, meant as a pivotal and quantitatively heavy role of financial operators, emerges also as a clear characteristic of the extended network.
"You're my best friend."
Authors: Ringland Kathryn E. , Wolf Christine T.
Published: January 2022

The COVID-19 pandemic was a time of unexpected isolation for many, as well as a time fraught with uncertainty. In this article, we explore how many turned to playful online communities across a number of social media platforms as a place of connection and support.
Experimental and Numerical Analysis of Flow Behavior for Reverse Circulation Drill Bit with Inserted Swirl Vanes
Authors: Yang Cheng , Jiang Jianliang , Qi Bo , Cui Guoqing , Zhang Liyong , Chen Yunwang , Cao Pinlu
Published: January 2022

A swirling drill bit designed with an integrated vane swirler was developed to improve reverse circulation in down-the-hole hammer drilling. Its entrainment effect and influential factors were investigated by CFD simulation and experimental tests. The numerical results exhibit reasonable agreement with the experimental data, with a maximum error of 13.68%. In addition, the structural parameters of the swirler were shown to have an important effect on the reverse circulation performance of the drill bit, including the helical angle and number of spiral blades, swirler outlet area, and the flushing nozzles. The optimal parameters for the swirling drill bit without flushing nozzles include a helical angle of 60°, four spiral blades, and the area ratio of 2, while it is about 30°, 3, and 3 for the drill bit with flushing nozzles. Moreover, the entrainment ratio of the drill bit without flushing nozzles can be improved by nearly two times compared with one with flushing nozzles under the same conditions.
Comparison of 3D, 2D, and 1D Magnetotelluric Inversion Results on the Example of Data from Fore-Sudetic Monocline
Authors: Oryński Szymon , Jóźwiak Waldemar , Nowożyński Krzysztof , Klityński Wojciech
Published: January 2022

This study’s main objective is to better define and understand results for the most commonly used inversion algorithms in magnetotelluric data interpretation as part of geological exploration of the region of the Dolsk fault and the Odra fault. The data obtained from the eastern part of Fore-Sudetic Monocline measurements were used to describe the boundaries of lithospheric blocks (terranes) and recognize their origin. The magnetotelluric (MT) soundings were carried out to achieve this goal. There were conducted 51 soundings on five quasiparallel profiles. That allows constructing a quasiregular mesh in the area of the Fore-Sudetic Monocline. This arrangement of the measuring grid allowed reducing the influence of the largest sources of disturbances on MT data. 1D and 2D models were created by using the inverse algorithms. The models were prepared for each profile separately. Further, parallel (ModEM) 3D inversion codes were applied. The area where the investigation was done involves the region of the Dolsk fault and the Odra fault. These zones are essential geologic borders of a regional nature, and they pull apart the crust blocks with different origins. It was vitally needed to correctly identify the crust and upper mantle structure around a part of the Fore-Sudetic Monocline. The paper shows how these key features of the geological structures are revealed using 1D, 2D, and 3D algorithms.
The Stability Improvement of α-Amylase Enzyme from Aspergillus fumigatus by Immobilization on a Bentonite Matrix
Authors: Yandri Yandri , Tiarsa Ezra Rheinsky , Suhartati Tati , Satria Heri , Irawan Bambang , Hadi Sutopo
Published: January 2022

The stability of the α-amylase enzyme has been improved from Aspergillus fumigatus using the immobilization method on a bentonite matrix. Therefore, this study aims to obtain the higher stability of α-amylase enzyme from A. fumigatus; hence, it is used repeatedly to reduce industrial costs. The procedures involved enzyme production, isolation, partial purification, immobilization, and characterization. Furthermore, the soluble enzyme was immobilized using 0.1 M phosphate buffer of pH 7.5 on a bentonite matrix, after which it was characterized with the following parameters such as optimum temperature, Michaelis constant (KM), maximum velocity

V

max

, thermal inactivation rate constant (ki), half-life (t1/2), and the change of energy due to denaturation (ΔGi). The results showed that the soluble enzyme has an optimum temperature of 55°C, KM of 3.04 mg mL−1 substrate,

V

max

of 10.90 μmole mL−1 min−1, ki of 0.0171 min−1, t1/2 of 40.53 min, and ΔGi of 104.47 kJ mole−1, while the immobilized enzyme has an optimum temperature of 70°C, KM of 8.31 mg mL−1 substrate,

V

max

of 1.44 μmole mL−1 min−1, ki of 0.0060 min−1, t1/2 of 115.50 min, and ΔGi of 107.37 kJ mole−1. Considering the results, the immobilized enzyme retained 42% of its residual activity after six reuse cycles. Additionally, the stability improvement of the α-amylase enzyme by immobilization on a bentonite matrix, based on the increase in half-life, was three times greater than the soluble enzyme.
Marketing Resource Allocation Strategy Optimization Based on Dynamic Game Model
Authors: Long Yan , Zhao Hongshan
Published: January 2022

Game theory has become an important tool to study the competition between oligopolistic enterprises. After combing the existing literature, it is found that there is no research combining two‐stage game and nonlinear dynamics to analyze the competition between enterprises for advertising. Therefore, this paper establishes a two‐stage game model to discuss the effect of the degree of firms’ advertising input on their profits. And the complexity of the system is analyzed using nonlinear dynamics. This paper analyzes and studies the dynamic game for two types of application network models: data transmission model and transportation network model. Under the time‐gap ALOHA protocol, the noncooperative behavior of the insiders in the dynamic data transmission stochastic game is examined as well as the cooperative behavior. In this paper, the existence of Nash equilibrium and its solution algorithm are proved in the noncooperative case, and the “subgame consistency” of the cooperative solution (Shapley value) is discussed in the cooperative case, and the cooperative solution satisfying the subgame consistency is obtained by constructing the “allocation compensation procedure.” The cooperative solution is obtained by constructing the “allocation compensation procedure” to satisfy the subgame consistency. In this paper, we propose to classify the packets transmitted by the source nodes, and by changing the strategy of the source nodes at the states with different kinds of packets, we find that the equilibrium payment of the insider increases in the noncooperative game with the addition of the “wait” strategy. In the transportation dynamic network model, the problem of passenger flow distribution and the selection of service parameters of transportation companies are also studied, and a two‐stage game theoretical model is proposed to solve the equilibrium price and optimal parameters under Wardrop’s criterion.
Apolipoprotein A1-Related Proteins and Reverse Cholesterol Transport in Antiatherosclerosis Therapy: Recent Progress and Future Perspectives
Authors: Xu Xiuting , Song Zikai , Mao Bao , Xu Guoliang
Published: January 2022

Hyperlipidemia characterized by abnormal deposition of cholesterol in arteries can cause atherosclerosis and coronary artery occlusion, leading to atherosclerotic coronary heart disease. The body prevents atherosclerosis by reverse cholesterol transport to mobilize and excrete cholesterol and other lipids. Apolipoprotein A1, the major component of high-density lipoprotein, plays a key role in reverse cholesterol transport. Here, we reviewed the role of apolipoprotein A1-targeting molecules in antiatherosclerosis therapy, in particular ATP-binding cassette transporter A1, lecithin-cholesterol acyltransferase, and scavenger receptor class B type 1.
Interleukin 21 Receptor Affects Adipogenesis of Human Adipose-Derived Stem/Stromal Cells
Authors: Falavinha Bruna Cristina , Barisón María Julia , Rebelatto Carmen Lúcia Kuniyoshi , Marcon Bruna Hilzendeger , de Melo Aguiar Alessandra , da Silva Evelin Brandão , Stimamiglio Marco Augusto , Shigunov Patrícia
Published: January 2022

Dysfunctions in adipose tissue cells are responsible for several obesity-related metabolic diseases. Understanding the process of adipocyte formation is thus fundamental for understanding these diseases. The adipocyte differentiation of adipose-derived stem/stromal cells (ADSCs) showed a reduction in the mRNA level of the interleukin 21 receptor (IL21R) during this process. Although the receptor has been associated with metabolic diseases, few studies have examined its function in stem cells. In this study, we used confocal immunofluorescence assays to determine that IL21R colocalizes with mitochondrial protein ATP5B, ALDH4A1, and the nucleus of human ADSCs. We demonstrated that silencing and overexpression of IL21R did not affect the cell proliferation and mitochondrial activity of ADSCs. However, IL21R silencing did reduce ADSC adipogenic capacity. Further studies are needed to understand the mechanism involved between IL21R and the adipogenic differentiation process.
Econometric Modeling to Measure the Efficiency of Sharpe’s Ratio with Strong Autocorrelation Portfolios
Authors: Chahuán-Jiménez Karime , Rubilar-Torrealba Rolando , de la Fuente-Mella Hanns
Published: January 2022

Sharpe’s ratio is the most widely used index for establishing an order of priority for the portfolios to which the investor has access, and the purpose of this investigation is to verify that Sharpe’s ratio allows decisions to be made in investment portfolios considering different financial market conditions. The research is carried out by autoregressive model (AR) of the financial series of returns using Sharpe’s ratio for evaluations looking over the priority of financial assets which the investor can access while observing the effects that can cause autocorrelated series in evaluation measures for financial assets. The results presented in this study confirm the hypothesis proposed in which Sharpe’s ratio allows decisions to be made in the selection of investment portfolios under normal conditions thanks to the definition of a robustness function, whose empirical estimation shows an average 73% explanation of the variance in the degradation of the Spearman coefficient for each of the performance measures; however, given the presence of autocorrelation in the financial series of returns, this similarity is broken.
Identification of Key Genes Associated with Endothelial Cell Dysfunction in Atherosclerosis Using Multiple Bioinformatics Tools
Authors: Zhang Guofu , Yu Hui , Su Jingjing , Chi Chao , Su Lide , Wang Fenglin , Zheng Ying , Xie Baodong , Kang Kai
Published: January 2022

Atherosclerosis is the most notable cardiovascular disease, the latter being the main cause of death globally. Endothelial cell dysfunction plays a major role in the pathogenesis of atherosclerosis. However, it is currently unclear which genes are involved between endothelial cell dysfunction and atherosclerosis. This study was aimed at identifying these genes. Based on the GSE83500 dataset, the quantification of endothelial cell function was conducted using single‐sample gene set enrichment analysis; the coexpression modules were conducted using weighted correlation network analysis. After building module‐trait relationships, tan and yellow modules were regarded as hub modules. 10 hub genes from each hub module were identified by the protein‐protein interaction network analysis. The key genes (RAB5A, CTTN, ITGB1, and MMP9) were obtained by comparing the expression differences of the hub gene between atherosclerotic and normal groups from the GSE28829 and GSE43292 datasets, respectively. ROC analysis showed the diagnostic value of key genes. Moreover, the differential expression of key genes in normal and atherosclerotic aortic walls was verified. In vitro, we establish a model of ox‐LDL‐injured endothelial cells and transfect RAB5A overexpression and shRNA plasmids. The results showed that overexpression of RAB5A ameliorates the proliferation and migration function of ox‐LDL‐injured endothelial cells, including the ability of tubule formation. It was speculated that the interferon response, Notch signaling pathways, etc. were involved in this function of RAB5A by using gene set variation analysis. With the multiple bioinformatics analysis methods, we detected that yellow and tan modules are related to the abnormal proliferation and migration of endothelial cells associated with atherosclerosis. RAB5A, CTTN, ITGB1, and MMP9 can be used as potential targets for therapy and diagnostic markers. In vitro, overexpression of RAB5A can ameliorate the proliferation and migration function of ox‐LDL‐injured endothelial cells, and the possible molecules involved in this process were speculated.