bluuebunny/crossref_metadata_2025 huggingface dataset:
Assembly Modeling and Analysis of Integral Fit Joints for Composite Transportation Structures
Authors: Lee David E. , Hahn H. Thomas
Published: February 2021

In order to reduce assembly complexity and enhance the performance of structural elements utilized in transportation systems, a novel approach is presented that uses integral fit joints in the assembly of fiber-reinforced composite structural elements. While the application of composite materials in transportation structures is not new or unique, their use coupled with integral fit joint designs affords a multi-magnitude reduction in the number of components required to assemble transportation systems. Essential to this effort is the need to effectively model and analyze the composite integral fit joint specifically focused on assembly. This paper introduces pertinent issues in the design and assembly of transportation systems, the assembly of their structural joints, and defines assembly models and analysis methods for composite integral fit (CIF) joints.
A Critical Review of Tube and Sheet Metal Hydroforming Technology
Authors: An Jian , Soni A. H.
Published: February 2021

The hydroforming technology, which is rapidly gaining popularity in the sheet metal and tube forming industry is reviewed. The features and the characteristics of the hydroforming process are described. The uniformly distributed fluid pressure covers the back side of the sheet as a die generates many advantages in the technical point of view as improving the part surface quality, reducing the forming severity and smoothing the thickness distribution. The benefits of using hydroforming technology are examined and analyzed in a technical level. The better part quality, less cost of tooling, materials saving and part weight reduction can be achieved using the hydroforming technology. The design methodologies for the hydroforming process parameters are reviewed and discussed in a certain detail. Computer-aided-engineering such as finite element simulation is suggested for such process parameter design.
The Integration of a SMT Fully-Automated Rework Cell for Fine-Pitch Surface Mounted Devices
Authors: Fidan Ismail , Ruff Larry , Derby Stephen
Published: February 2021

Surface mounted components have become the choice of the electronics manufacturing industry to solve problems in the complex circuit boards. New components using increased lead counts on finer pitches make manufacturing difficult. The increased complexity, cost, and lead count of the Surface Mount Technology (SMT) components, and also the increasing compactness of the SMT assemblies have demanded the creation of newer rework tools as an essential part of electronics manufacturing. Therefore, it becomes essential to have a well-controlled process to assure that rework is not only possible but that it is consistent and flawless. Automation is the common answer to achieve both efficiency and quality. This paper describes a system for the automated rework of fine pitch components that is under development as part of the Center for Integrated Electronics and Electronics Manufacturing (CIEEM) at Rensselaer.
Explicit Solution for the Forward Displacement Analysis of the Stewart Platform Manipulator
Authors: Jin Yao , Hai-Rong Fang
Published: February 2021

A method is presented to directly solve the problem of the forward displacement analysis of the Stewart platform manipulator. With algebraic elimination and the use of only one extra sensor, the explicit expressions on the forward displacement solution is obtained so that the method may enable designers to get the best compromise between the supplementary cost and complexity of the manipulator and the computation time for solving the forward displacement analysis. A numerical example is given to illustrate the method presented.
Orientation Capability and Robot Wrists
Authors: Holland Neil , Dai Jian S. , Kerr David R.
Published: February 2021

This paper introduces a measure of the orientation capability of manipulator wrists, and a means of representing orientation capability. Wrists with the various combinations of roll, pitch and yaw joints, with one, two or three joints are studied. It is shown that for all non-degenerate orthogonal three joint wrists, the image space representing the orientation capability is doubly-covered, and the possibilities for restricting joint angles to make it singly-covered are given. Degenerate postures for each configuration are also given, and singularity-free wrists with three joints are discussed.
Task-Oriented Direct Synthesis of Serial Manipulators Using Moment Invariants
Authors: Dai Jian S. , Holland Neil , Kerr David R.
Published: February 2021

This paper applies the finite twist mapping to spatial manipulators and gives a new approach for the direct synthesis of serial manipulators by using moment invariants and task decomposition. The task is represented in an image space as a cluster of a large number of points and is related to the finite twist of the manipulator. For a given task, the new approach applies a series of analysis to the data, and produces a set of invariant criteria. The type and disposition of the proximal joint are identified, and the remaining regional structure may then be designed. The approach is based upon the numerical analysis of a task without recourse to graphical analysis and is computer programmable. This new design procedure is illustrated with a flowchart and a numerical example is given.
Kinematic Modeling of Underactuated Mechanical Grippers
Authors: Montambault Serge , Gosselin Clément M.
Published: February 2021

This paper presents the concept of underactuation applied to grippers and mechanical hands. The main objective of this work is the kinematic analysis and design of underactuated mechanisms. First, the kinematic and static modeling of these mechanisms is addressed and a general model is proposed. Then, a two-degree-of-freedom underactuated gripper based on a five-bar planar mechanism is studied in order to illustrate the usefulness of the model in a context of analysis and design.
Development of an Integrated System for Cam Design and Manufacture With Graphical User Interface
Authors: Aziz Rosman
Published: February 2021

The development of a Windows-based software package for the design and manufacture of cams is presented. There are four main modules in this software consisting of design, display, animation and NC program generation. From the data input the motion curves are constructed using building-block approach where proper blending at joint points are ensured. The interactive graphical user interface provide easy data entry for the user, and the output display give excellent graphics. B-spline curve fitting and techniques for offset free-form curves were employed to generate cutter path and cam profile. In order to evaluate the software, test samples were made, using the NC program generated. The test results were satisfactory.
A Geometric Model for Analysis and Design of Delta Parallel Robots
Authors: Gao Feng , Gruver William A. , Wang Hongrui , Zhang Yuru
Published: February 2021

A geometric model of the solution space for delta parallel robots is derived. We present an approach that classifies delta parallel robots in terms of 3-crank, 3-rocker, and change point mechanisms. By representing performance facors as character-istic curves within the model, the technique provides a foundation for investigating the relationships between robot performance and the link lengths of all possible mechanisms.
A Multi-Purpose Off-Line Path Planner Based on an A* Search Algorithm
Authors: Rankin Arturo L. , Crane Carl D.
Published: February 2021

Efficient navigation of an autonomous mobile robot through a well-defined environment requires the ability of the robot to plan paths. An efficient and reliable planar off-line path planner has been developed that is based on the A* search method. Using this method, two types of planning are accomplished. The first uses a map of all known obstacles to determine the shortest-distance path from a start to goal configuration. The second determines the shortest path along a network of predefined roads. For the most complicated environment of obstacles and roads, a near-optimal piecewise-linear path is found within a few seconds. The planner can generate paths for robots capable of rotation about a point as well as car-like robots that have a minimum turning radius. For car-like robots, the planner can generate forward and reverse paths. This software is currently implemented on a computer controlled Kawasaki Mule 500 all-terrain vehicle and a computer controlled John Deere 690 excavator.
Choice of Riemannian Metrics for Rigid Body Kinematics
Authors: Žefran Miloš , Kumar Vijay , Croke Christopher
Published: February 2021

The set of spatial rigid body motions forms a Lie group known as the special Euclidean group in three dimensions, SE(3). Chasles’s theorem states that there exists a screw motion between two arbitrary elements of SE(3). In this paper we investigate whether there exist a Riemannian metric whose geodesics are screw motions. We prove that no Riemannian metric with such geodesics exists and we show that the metrics whose geodesics are screw motions form a two-parameter family of semi-Riemannian metrics.
Singularity and Dexterity Analysis of the Carpal Wrist
Authors: Canfield Stephen L. , Ganino Anthony J. , Salerno Robert J. , Reinholtz Charles F.
Published: February 2021

This paper further explores the potential advantages of a symmetric, parallel-actuated pointing device known as the “Carpal wrist.” Much like its natural counterpart, the Carpal wrist has eight primary links, corresponding to the eight carpal bones of the human wrist, a parallel actuation scheme, similar to the flexor and extensor carpi muscles along the forearm, and an open interior passage, which forms a protected tunnel for routing hoses and electrical cables. The Carpal wrist also has the significant advantages of possessing closed form forward and inverse kinematic solutions and a large, dexterous workspace that is free of interior singularities (either considered separately or as part of a manipulator arm). As a result of its symmetric, parallel architecture, the wrist has a large payload capacity and can easily be adapted to a variety of actuation schemes. One embodiment of the Carpal wrist is shown in Fig. 1.
Control of Truss-Based Manipulators Using Virtual Serial Models
Authors: Williams Robert L. , Mayhew James B.
Published: February 2021

This paper introduces a novel method for Cartesian trajectory and performance optimization control of kinematically-redundant truss-based manipulators (TBMs), The Virtual Serial Manipulator Approach. The approach is to model complex in-parallel-actuated TBMs as simpler kinematically-equivalent virtual serial manipulators. Standard control methods for kinematically-redundant serial manipulators can then be adapted to the real-time control of TBMs. The forward kinematics transformation can be calculated more efficiently using the equivalent virtual parameters, compared to the computationally intensive in-parallel-actuated forward kinematics transformation. The method is applicable to any TBM whose modules can be modeled as a virtual serial chain. It also handles TBMs constructed of dissimilar modules, and compound manipulators with serial and in-parallel-actuated joints. The method is applicable for any level of kinematic redundancy.
Design Optimization of Variable Stroke Compressors to Minimize Vibration by Using Asymptotic Analysis
Authors: Ashrafiuon Hashem , Whitman Alan M.
Published: February 2021

A design optimization of a variable displacement compressor, in order to minimize its crankshaft vibration, is presented. A vibration mount installed between the flywheel and crankshaft is used as the optimizing element; the stiffness and damping values of the mount are selected so that the shaft vibration level is minimized over the cruise speed range while the maximum twist angle acceleration amplitude and transmitted torque are kept within acceptable limits for the entire operating speed range. An asymptotic analysis is used to obtain the nonlinear vibrational response. This analysis provides analytic expressions for the motion and forces in terms of the operating speed and other geometric, kinetic, and dynamic parameters. Consequently, the calculation of the objective and constraint functions is simple to do. A result of the analysis is that the optimal design is insensitive to changes in the magnitude and shape of the cylinder pressure excitation.
Analytical and Experimental Investigations of a Multi-Degree-of-Freedom Flexible Cam-Follower Mechanisma
Authors: Khanuja Sukhwant S. , Mahyuddin Andi I. , Midha Ashok
Published: February 2021

A multi-degree-of-freedom model is developed herein for prediction of response of an experimental cam-follower mechanism. Both transverse and axial flexibility of the follower rod and return spring, as well as transverse and torsional flexibility of the camshaft are included. The camshaft is assigned two rotational degrees of freedom, one at the cam and the other at the flywheel. The follower mass motion is also described by two degrees of freedom, one each in the axial and the transverse directions. The model takes into account the fluctuating camshaft angular speed and treats it as an input excitation. The governing second-order, nonlinear, nondimensionalized ordinary differential equations of motion, with time-periodic coefficients, are developed. In doing so, a comprehensive modeling of the kinematics of deformation of the flexible camshaft and follower system is considered, with the first inclusion of the transverse flexibility of the follower rod and return spring. With axial deflection, the transverse flexibility of the return spring gives rise to a phenomenon defined as moment stiffening. The transverse degree of freedom of the follower mass significantly influences the equivalent axial stiffness of the system. Its inclusion in the equation of motion yields a more accurate prediction of the experimental system behavior.
Design of a Two-Input Linkage-Based Motor
Authors: Shanshal Yassir , Farhang Kambiz
Published: February 2021

This paper proposes the use of a seven-bar linkage mechanism to obtain a multiply actuated motor. Design of two input mechanisms is presented involving two synthesis sub-tasks of input motion synthesis and dimensional synthesis. To this end a design methodology is presented based on the theory of small crank mechanisms. For the case of small motion, approximate equations are developed with the premise that as a result of small reciprocating motion of the input actuators, the motion of every link, with the exception of the output, is small. The motion, in turn, is expressed as a sum of an average and a small oscillatory angular motion about the average. A set of design equations are obtained from the approximate kinematic equations. The design methodology is exemplified using the synthesis of a seven-link mechanism with two translating inputs.
A Tooth Contact Analysis Model for Crossed Axis Helical Gears Under Load
Authors: Zhang Y. , Fang Z.
Published: February 2021

This paper presents an approach for the analysis of tooth contact and load distribution of helical gears with crossed axis. The approach is based on a tooth contact model that accommodates the influence of tooth profile modifications, gear manufacturing errors and tooth surface deformation on gear mesh quality. In the approach, the tooth contact load is assumed to be distributed along the tooth surface line that coincides with the relative principal direction of the contacting tooth surfaces. The model in this paper provides a quantitative analysis on gear transmission errors, contact patterns and the load distribution of helical gears with crossed axes when the tooth surfaces are deformed under load. As a numerical example, the contact of a pair of helical gears with a small crossing angle is analyzed by the computer program that implements the approach.
Closed-Form Displacement Analysis of 9-Link, 2-DOF and 10-Link, 3-DOF Mechanisms
Authors: Almadi Abdulaziz N. , Dhingra Anoop K. , Kohli Dilip
Published: February 2021

This paper addresses the closed-form displacement analysis problem of all mechanisms which can be derived from 9-link kinematic chains with 2-DOF, and 10-link kinematic chains with 3-DOF. The successive elimination procedure developed in the companion paper is used to solve the resulting displacement analysis problems. The input-output polynomial degrees as well as the number of assembly configurations for all mechanisms resulting from 40 9-link kinematic chains, and 74 10-link kinematic chains with non-fractionated degrees of freedom (DOF) are given. The computational procedure is illustrated through two numerical examples. The displacement analysis problem for all mechanisms resulting from these chains is completely solvable, in closed-form, devoid of any spurious roots.
Synthesis of Force-Generating Mechanisms
Authors: Tidwell Paul H. , Reinholtz Charles F. , Soper R. Randall
Published: February 2021

This work presents a unified method for the kinematic synthesis of mechanical-advantage function-generating mechanisms. These devices produce a specified nonlinear force or torque as a function of input position with resisting energy supplied to the mechanism from an external energy storage device such as a spring or load weight. This work differs from most past work in that the positions of the link carrying the external resisting load need not he specified.
A New Method and Automatic Generation for Kinematic Error Analysis of Complex Planar Mechanisms Based on the Ordered Single-Opened-Chains
Authors: Shan Song-Qing , Yang Ting-Li
Published: February 2021

This paper presents a new method for kinematic error analysis of planar complex mechanisms, i.e., the ordered single -opened -chains method. This approach is based on the ordered single-opened chains (namely, series binary links, in short, SOCs)and makes use of the properties of SOCs and the network constraint relationships between SOCs. Its mathematical model harmonizes with the structure, kinematics, and dynamics model of mechanisms. The kinematic error analysis equations with few unknown variables can be automatically generated and easily solved. Therefore, any planar complex mechanism can be automatically decomposed into a series of the ordered single-opened-chains and then its kinematic error analysis can be easily completed through this method. Perhaps, the most attractive features of this method are its high automation and convergence in computer implementations.

This work describes the principle of the ordered SOC method, introduces its computer automatic generation and compiles the corresponding computer program KEAPL. Two Examples are given at the end of the paper.

The proposed method can be easily extended to the kinematic error analysis of the spatial mechanisms.
Dynamic Analysis of Geared Robotic Mechanisms Using Graph Theory
Authors: Tsai Lung-Wen , Chen Dar-Zen , Lin Ta-Wei
Published: February 2021

A systematic methodology is developed for the dynamic analysis of a class of geared robotic mechanisms. The concepts of canonical graph representation, the equivalent open-loop chain, and the mechanical transmission lines of a mechanism are used to organize the analysis. The approach modifies the Newton-Euler recursive inverse dynamics algorithm for open-loop chains and tree structures to include gear joints. A recursive method for the evaluation of reaction forces is developed. It is shown that reaction forces can be efficiently computed from the highest level primary links followed by the secondary links, one or two levels at a time, working toward the base. This procedure is especially useful when the evaluation of dynamic loads of bearings and teeth teeth is desired for the design of such mechanisms. A two degree-of-freedom robot manipulator is used as an illustrative example.
Trajectory Control for Robotic Arc Welding Applications
Authors: Balkan Tuna
Published: February 2021

In this study, a PC based program is developed for robotic welding applications. This program includes synthetic generation of Cartesian trajectories based on prespecified points on the trajectory and predetermined velocity profile. Such points can be provided in the teach mode or by using a vision system assisted by a special algorithm. The control algorithm is based on the measurement of joint variable positions and rates resulting in a closed-loop system with a model-based part. These algorithms are applied to an industrial robot performing arc welding weaving applications and typical performance curves are obtained under simulated conditions.
Minimizing the Strain Energy for Flexible-Link Cooperating Manipulators
Authors: Sun Qiao , Sharf Inna , Nahon Meyer
Published: February 2021

In control of cooperating manipulator systems, force distribution is a central problem. For rigid manipulators, solutions are based on various criteria such as minimum potential damage to the grasped object, minimum energy consumption and optimal load distribution in actuators. However, when considering manipulators with structural flexibility, minimizing the deflections of the mechanical components becomes a highly desirable objective. In this paper, we propose a force distribution scheme based on a local minimum of the strain energy stored in the elastic links of the cooperating manipulators. Numerical example are given to demonstrate the effectiveness of the scheme.
The Cylindroid Associated With Finite Motions of the Bennett Mechanism
Authors: Huang Chintien
Published: February 2021

The finite kinematic geometry of the Bennett mechanism is explored, and a surprising finding is uncovered in this paper. The screw axes of all possible coupler displacements of the mechanism from any given configuration are shown to form a cylindroid. The screw system of the coupler displacement is obtained by using the intersection of finite screw systems associated with two corresponding revolute-revolute dyads. Inverse finite kinematic analysis is also performed to verify this new linear property of the Bennett mechanism.
Modeling and Identification of Non-Geometric Parameters in Semi-Flexible Serial Robotic Mechanisms
Authors: Cléroux Louise , Gosselin Clément M.
Published: February 2021

In order to ensure the rigid body assumption, serial manipulators have generally been overdesigned. This has resulted in large, heavy and bulky robots that can only manipulate loads which are small when compared to their own weight. Therefore, structural flexibilities are studied here in order to maintain static accuracy while reducing the weight of the robots. In this paper, the modeling and identification of serial manipulators with flexible joints and links is addressed. A general model is developed in order to take into account the flexibilities, and an algorithm is proposed for the identification of mechanisms from measured static poses.
On the Generation Synthesis of Movable Octahedral 6R Mechanisms
Authors: Lee Chung-Ching
Published: February 2021

The geometric characteristics of three well-known movable octahedral 6R mechanisms are described and then, by matrix algebra method, we derive their general displacement closed-form solutions for further investigation and analysis. Based on the fundamentals of three dimensional analytical coordinate geometry, a systematic approach is offered to generate the configuration of movable octahedral 6R mechanism with the help of computer graphics. In addition, a user-friendly computer aided program implementing the process of generation synthesis can be developed in Autolisp, a Lisp language interpreter within autoCAD. The numerical results for every generation and their constrained motion are confirmed by the derived analytical solutions. The physical models of these synthesized mechanisms are also built respectively.
Speech emotion recognition based on transfer learning from the FaceNet framework
Authors: Liu Shuhua , Zhang Mengyu , Fang Ming , Zhao Jianwei , Hou Kun , Hung Chih-Cheng
Published: February 2021

Speech plays an important role in human–computer emotional interaction. FaceNet used in face recognition achieves great success due to its excellent feature extraction. In this study, we adopt the FaceNet model and improve it for speech emotion recognition. To apply this model for our work, speech signals are divided into segments at a given time interval, and the signal segments are transformed into a discrete waveform diagram and spectrogram. Subsequently, the waveform and spectrogram are separately fed into FaceNet for end-to-end training. Our empirical study shows that the pretraining is effective on the spectrogram for FaceNet. Hence, we pretrain the network on the CASIA dataset and then fine-tune it on the IEMOCAP dataset with waveforms. It will derive the maximum transfer learning knowledge from the CASIA dataset due to its high accuracy. This high accuracy may be due to its clean signals. Our preliminary experimental results show an accuracy of 68.96% and 90% on the emotion benchmark datasets IEMOCAP and CASIA, respectively. The cross-training is then conducted on the dataset, and comprehensive experiments are performed. Experimental results indicate that the proposed approach outperforms state-of-the-art methods on the IEMOCAP dataset among single modal approaches.
Moving Toward Authentic, Learning-Oriented Assessment in Coach Education
Authors: McCarthy Liam , Allanson Ashley , Stoszkowski John
Published: February 2021

As sports coaching continues to professionalize, the demand for and importance placed upon high-quality education and development programs for sports coaches is increasing. As a result, the landscape of provision is changing, and there is now a recognition of the key role that higher education institutes play in the education, development, and assessment of sports coaches. In this insights article, the authors argue that as there is a scarcity of research focused solely on assessment as a feature of coach education programs, there is something to be gained from examining how higher education institutes assess sports coaches. This represents an important contribution to the research literature, given that assessment is a feature of nearly all coach education programs and that the attainment of a specific award communicates to stakeholders (e.g., employers, athletes, parents) that a precise standard of practice has been met. As such, the authors identify how some higher education institutes are addressing the issue of assessment with sports coaches and highlight a series of assessment principles, alongside practical examples from the literature, which are intended to stimulate conversation in what the authors argue is an important area of study.
Exposure to Sustained Flexion Impacts Lumbar Extensor Spinae Muscle Fiber Orientation
Authors: Pinto Brendan L. , Viggiani Daniel , Callaghan Jack P.
Published: February 2021

The lumbar extensor spinae (LES) has an oblique orientation with respect to the compressive axis of the lumbar spine, allowing it to counteract anterior shear forces. This mechanical advantage is lost as spine flexion angle increases. The LES orientation can also alter over time as obliquity decreases with age and is associated with decreased strength and low back pain. However, it is unknown if LES orientation is impacted by recent exposures causing adaptations over shorter timescales. Hence, the effects of a 10-minute sustained spine flexion exposure on LES orientation, thickness, and activity were investigated. Three different submaximally flexed spine postures were observed before and after the exposure. At baseline, orientation (P < .001) and thickness (P = .004) decreased with increasingly flexed postures. After the exposure, obliquity further decreased at low (pairwise comparison P < .001) and moderately (pairwise comparison P = .008) flexed postures. Low back creep occurred, but LES thickness did not change, indicating that decreases in orientation were not solely due to changes in muscle length at a given posture. Activation did not change to counteract decreases in obliquity. These changes encompass a reduced ability to offset anterior shear forces, thus increasing the potential risk of anterior shear-related injury or pain after low back creep-generating exposures.
Vaccine trials ramp up in children and adolescents
Authors: Couzin-Frankel Jennifer
Published: February 2021

Doctors stress need to vaccinate young people once shots are available.
Transition states and spin-orbit structure
Authors: Rakitzis T. Peter
Published: February 2021

Spin-orbit coupling is required to explain a set of scattering resonances in the F + HD reaction
Identification of a Diguanylate Cyclase That Facilitates Biofilm Formation on Electrodes by Shewanella oneidensis MR-1
Authors: Matsumoto Akiho , Koga Ryota , Kanaly Robert A. , Kouzuma Atsushi , Watanabe Kazuya
Published: February 2021

Bioelectrochemical systems (BESs) have attracted wide attention owing to their utility in sustainable biotechnology processes, such as microbial fuel cells and electrofermentation systems. In BESs, electrochemically active bacteria (EAB) form biofilms on electrode surfaces, thereby serving as effective catalysts for the interconversion between chemical and electric energy.
Performance of Four IgM Antibody Assays in the Diagnosis of Measles Virus Primary Infection and Cases with a Serological Profile Indicating Reinfection
Authors: Semmler Georg , Aberle Stephan Walter , Griebler Hannah , Richter Lukas , Schmid Daniela , Stiasny Karin , Holzmann Heidemarie , Weseslindtner Lukas
Published: February 2021

The object of this study was to determine the diagnostic performance of four commercially available IgM tests in the diagnosis of measles virus (MeV) primary infection and cases with a serological profile indicating reinfection. Sera from 187 patients with MeV primary infection, 30 patients with suspected reinfection (after vaccine failure), and 153 patients with rash-like symptoms after exclusion of MeV infection were retested with four IgM tests.
Medical costs and out-of-pocket expenditures associated with multimorbidity in China: quantile regression analysis
Authors: Zhao Yang , Atun Rifat , Anindya Kanya , McPake Barbara , Marthias Tiara , Pan Tianxin , Heusden Alexander van , Zhang Puhong , Duolikun Nadila , Lee John Tayu
Published: February 2021

Objective

Multimorbidity is a growing challenge in low-income and middle-income countries. This study investigates the effects of multimorbidity on annual medical costs and the out-of-pocket expenditures (OOPEs) along the cost distribution.

Methods

Data from the nationally representative China Health and Retirement Longitudinal Study (CHARLS 2015), including 10 592 participants aged ≥45 years and 15 physical and mental chronic diseases, were used for this nationally representative cross-sectional study. Quantile multivariable regressions were employed to understand variations in the association of chronic disease multimorbidity with medical cost and OOPE.

Results

Overall, 69.5% of middle-aged and elderly Chinese had multimorbidity in 2015. Increased number of chronic diseases was significantly associated with greater health expenditures across every cost quantile groups. The effect of chronic diseases on total medical cost was found to be larger among the upper tail than those in the lower tail of the cost distributions (coefficients 12, 95% CI 6 to 17 for 10th percentile; coefficients 296, 95% CI 71 to 522 for 90th percentile). Annual OOPE also increased with chronic diseases from the 10th percentile to the 90th percentile. Multimorbidity had larger effects on OOPE and was more pronounced at the upper tail of the health expenditure distribution (regression coefficients of 8 and 84 at the 10th percentile and 75th percentile, respectively).

Conclusion

Multimorbidity is associated with escalating healthcare costs in China. Further research is required to understand the impact of multimorbidity across different population groups.
A double-edged sword—telemedicine for maternal care during COVID-19: findings from a global mixed-methods study of healthcare providers
Authors: Galle Anna , Semaan Aline , Huysmans Elise , Audet Constance , Asefa Anteneh , Delvaux Therese , Afolabi Bosede Bukola , El Ayadi Alison Marie , Benova Lenka
Published: February 2021

Introduction

The COVID-19 pandemic has led to a rapid implementation of telemedicine for the provision of maternal and newborn healthcare. The objective of this study was to document the experiences with providing telemedicine for maternal and newborn healthcare during the pandemic among healthcare professionals globally.

Methods

The second round of a global online survey of maternal and newborn health professionals was conducted, disseminated in 11 languages. Data were collected between 5 July and 10 September 2020. The questionnaire included questions regarding background, preparedness and response to COVID-19, and experiences with providing telemedicine. Descriptive statistics and qualitative thematic analysis were used to analyse responses, disaggregated by country income level.

Results

Responses from 1060 maternal and newborn health professionals were analysed. Telemedicine was used by 58% of health professionals and two-fifths of them reported not receiving guidelines on the provision of telemedicine. Key telemedicine practices included online birth preparedness classes, antenatal and postnatal care by video/phone, a COVID-19 helpline and online psychosocial counselling. Challenges reported lack of infrastructure and technological literacy, limited monitoring, financial and language barriers, lack of non-verbal feedback and bonding, and distrust from patients. Telemedicine was considered as an important alternative to in-person consultations. However, health providers emphasised the lower quality of care and risk of increasing the already existing inequalities in access to healthcare.

Conclusions

Telemedicine has been applied globally to address disruptions of care provision during the COVID-19 pandemic. However, some crucial aspects of maternal and newborn healthcare seem difficult to deliver by telemedicine. More research regarding the effectiveness, efficacy and quality of telemedicine for maternal healthcare in different contexts is needed before considering long-term adaptations in provision of care away from face-to-face interactions. Clear guidelines for care provision and approaches to minimising socioeconomic and technological inequalities in access to care are urgently needed.
Effects of feeding two different blends of essential oils to finishing steers on growth performance, carcass characteristics, meat quality, meat composition, and shelf life
Authors: Dorleku J.B. , Wang L.M. , Zhou Z.Y. , Mandell I.B. , Bohrer B.M.
Published: February 2021

The objective was to evaluate the effects of feeding two different commercially available blends of essential oils to finishing steers to replace conventional feed additives in feedlot diets. Angus-based crossbred steers [N = 43; starting body weight (BW) = 466 ± 31 kg] were used in a randomized complete block design. Steers were randomly assigned to four different dietary treatments for the 100 d finishing period in which steers were fed high-moisture corn/alfalfa silage/soybean meal diets. Dietary treatments included a negative control (no additives; CON), a positive control (33 mg·kg−1 monensin and 11 mg·kg−1 tylosin added to the diet; M/T), and two different proprietary blends of essential oils [EO-1: 1 g·steer−1·d−1 Victus Liv (DSM Nutritional Products) and EO-2: 4 g·steer−1·d−1 Fortissa Fit 45 (Provimi Canada ULC)]. Growth performance, carcass characteristics, meat quality, sensory attributes (excluding juiciness), most fatty acid parameters, and shelf-life (color and lipid oxidative stability) were generally unaffected by the inclusion of two different commercially available essential oil blends when compared with both a negative control (CON) and a positive control (M/T). This indicates that commercially available essential oil blends may show promise as a replacement to conventional feed additives like antibiotics without causing negative effects to meat quality, storage stability, and eating experience.
The Mechanism of Aluminum Vanadate in Aqueous Zinc Ion Batteries with Ultra-Long Cycle Life
Authors: Su Qingsong , Yang Zhanhong , Chen Linlin , Yuan Liang , Chen Hongzhe , Rong Yao , Deng Lie , Wu Jian
Published: February 2021

There are few cathode materials suitable for aqueous zinc ion batteries with high capacity and long cycle stability. Herein, H11Al2V6O23.2 (defined as HAVO) microspheres are synthesized by hydrothermal method as cathode material, which exhibits a maximum discharge capacity of 236 mA g−1 at 100 mA g−1. Significantly, ultra-long cycle performance of 100 mA g−1 with an extraordinary capacity retention of 90% is achieved after 5000 cycles at 8 A g−1. The research finds that the excellent performance is attributed to the extraordinary layer spacing of 13.37 Å and reveals the zinc storage mechanism of the HAVO electrode.
The Effect of Various Graphite Additives on Positive Active Mass Utilization of the Lead-Acid Battery
Authors: Kosacki Julian , Dogan Fatih
Published: February 2021

Various graphite additives were incorporated into the positive paste in a range of amounts to study and compare their effects on the positive active mass utilization of lead-acid batteries. Four types of graphite—two anisotropic, one globular, and one fibrous—were investigated by SEM, XRD, and Raman spectroscopy. Their physico-chemical properties were correlated to the electrochemical performances of 2 V test batteries under a wide range of conditions. This works presents the influence of graphite additives’ structural order, phase composition, particle size, morphology, and surface area on the formation, initial cycling, and electrochemical utilization of the positive plate. The effects of various graphite on electrochemical performance were investigated using SEM, mercury porosimetry, and TGA/DSC to correlate the function of graphite on the positive active mass utilization of the lead-acid battery.
Review—Recent Development of Detection Methods for Controlling COVID-19 Outbreak
Authors: Madurani Kartika A. , Suprapto Suprapto , Syahputra Muhammad Yudha , Puspita Ika , Masudi Ahmad , Rizqi Hamdan Dwi , Hatta Agus Muhamad , Juniastuti Juniastuti , Lusida Maria Inge , Kurniawan Fredy
Published: February 2021

The current outbreak of Coronavirus disease 2019 (COVID-19) has become a health emergency of international concern since last December 2019. At the same time, the coronavirus pandemic also caused an economic crisis worldwide. All countries worldwide are competing to generate a qualified strategic plan for resolving this problem. Vaccine, treatment, and detection are the keys to control this pandemic. Global attempts to produce a suitable vaccine are ongoing in many laboratories. However, based on the failure of several previous vaccines, such as Ebola and dengue fever, has stimulated researchers to develop an effective and quick treatment. Effective treatment depends on the effectiveness of the detection method. Thus, a real-time, selective, and accurate detection method is urgently needed to detect if a person has been exposed to COVID-19. This paper is designed to discuss the current situation in controlling COVID-19 by several detection methods. The progress of each method is summarized and compared. Other information regarding the virus, such as the origin, transmission, and biomarkers of the virus, is also explained. The case progress of COVID-19 and its future directions also are discussed.
Relationship between serum myostatin levels and carotid-femoral pulse wave velocity in healthy young male adolescents: the MACISTE study
Authors: Pucci Giacomo , Ministrini Stefano , Nulli Migliola Elisa , Nunziangeli Luisa , Battista Francesca , D’Abbondanza Marco , Anastasio Fabio , Crapa Mariano Edoardo , Sanesi Leandro , Carbone Federico , Lupattelli Graziana , Vaudo Gaetano
Published: February 2021

Serum myostatin, a proteic compound known to regulate skeletal muscle growth and production of extracellular matrix, is independently associated with increased aortic stiffness in healthy male adolescents. This result sheds lights on the potential novel role of myokines in the early development of systemic hypertension and early vascular aging, as well as on their inhibition as a hypothetical therapeutic strategy to counteract vascular aging at an early stage of physical development.
Human skeletal muscle fiber type-specific responses to sprint interval and moderate-intensity continuous exercise: acute and training-induced changes
Authors: Skelly Lauren E. , Gillen Jenna B. , Frankish Barnaby P. , MacInnis Martin J. , Godkin F. Elizabeth , Tarnopolsky Mark A. , Murphy Robyn M. , Gibala Martin J.
Published: February 2021

We examined mixed-muscle and fiber type-specific responses to a single session and to 12 wk of moderate-intensity continuous training (MICT) and sprint interval training (SIT) in humans. Both interventions elicited generally similar responses, although the training-induced increases in type I fiber-specific markers of mitochondrial content were greater in MICT than in SIT. These findings advance our understanding of the potential role of fiber type-specific changes in determining the human skeletal muscle response to intermittent and continuous exercise.
Identification of MEDAG as a Hub Candidate Gene in the Onset and Progression of Type 2 Diabetes Mellitus by Comprehensive Bioinformatics Analysis
Authors: Yang Jing , Yu Ping
Published: February 2021

Objectives. We conducted the present study to identify novel hub candidate genes in the pathogenesis of type 2 diabetes mellitus (T2DM) and provide potential biomarkers or therapeutic targets for dealing with the disease. Methods. We conducted weighted gene coexpression network analysis on a series of the expression profiles of the pancreas islet of T2DM patients obtained from the Gene Expression Omnibus database to construct a weighted coexpression network. After dividing genes into separated coexpression modules, we identified a T2DM‐related module using Pearson’s correlation analysis. Then, hub genes were identified from the T2DM‐related module using the Maximal Clique Centrality method and validated by correlation analysis with clinical traits, differentially expressed gene analysis, validation in other datasets, and single‐gene gene set enrichment analysis (GSEA). Results. Genes were divided into 16 coexpression modules, and one module was identified as a T2DM‐related module. Four hub candidate genes were identified, and MEDAG was a novel hub candidate gene. The expression level of MEDAG was positively correlated with hemoglobin A1c (HbA1c) and was evidently overexpressed in the pancreas islet tissue of T2DM patients compared with normal control. Analyses on two other datasets supported the results. GSEA verified that MEDAG plays essential roles in T2DM. Conclusions. MEDAG is a novel hub candidate of T2DM, and its irregular expression in the pancreas islet plays vital roles in the pathogenesis of T2DM. MEDAG is a potential target of intervention in the future for the treatment of T2DM.
Why Being Physically Active or Inactive Affects Older Women’s Physical Role?
Authors: Ruiz-Montero Pedro Jesús , Rubio Laura , Dumitrache Cristina G. , Chiva-Bartoll Óscar
Published: February 2021

Background. Active aging is aimed at promoting quality of life in older adults. Nevertheless, the relationship between physical role and the practice of physical activity (PA) can be influenced by bodily pain feeling and by a low level of health‐related quality of life (HRQoL). Passive and active strategies are susceptible to being modified and constitute an important psychological predictor of adaptation to pain. This cross‐sectional study (1) analyzed the differences between inactive/active older adult women in terms of clinical and sociodemographic characteristics, pain coping strategies, and HRQoL; (2) studied the associations between pain coping strategies, the dimensions of the HRQoL questionnaire, and physical role; and (3) determined if passive strategies, bodily pain, physical function, and general health were significant mediators in the link between being inactive/active and physical role. Methods. Participants of the present cross‐sectional study completed measures of clinical and sociodemographic characteristics, HRQoL using the Short‐Form Health Survey‐36, and active and passive strategies using the Vanderbilt Pain Management Inventory (VPMI). Results. A total of 157 inactive (69.9 ± 7.1 years) and 183 active (68.8 ± 5.3 years) women from rural areas were included in the study. Both groups significantly differed in the majority of the clinical and sociodemographic characteristics measured, pain coping strategies, and HRQoL. Bodily pain, physical function, and general health predicted physical role. Moreover, passive strategies, bodily pain, physical function, and general health mediated the link between inactive/active participants and physical role. Conclusions. Being physically active or inactive contributes to a better understanding of the link between PA, pain coping strategies, and physical role in older women.
Multiple‐Coated PLGA Nanoparticles Loading Triptolide Attenuate Injury of a Cellular Model of Alzheimer’s Disease
Authors: Jia Lu , Nie Xiao-qi , Ji Hong-ming , Yuan Zhi-xiang , Li Rong-shan
Published: February 2021

Alzheimer’s disease (AD) is the most common neurodegenerative disease, which is associated with extracellular deposition of amyloid‐β proteins (Aβ). It has been reported that triptolide (TP), an immunosuppressive and anti‐inflammatory agent extracted from a Chinese herb Tripterygium wilfordii, shows potential neuroprotective effects pertinent to AD. However, the clinical use of TP for AD could be hampered due to its high toxicity, instability, poor water solubility, and nonspecific biodistribution after administration. In this paper, we reported a kind of multiple‐coated PLGA nanoparticle with the entrapment of TP and surface coated by chitosan hydrochloride, Tween‐80, PEG20000, and borneol/mentholum eutectic mixture (MC‐PLGA‐TP‐NP) as a novel nasal brain targeting preparation for the first time. The obtained MC‐PLGA‐TP‐NP was 147.5 ± 20.7 nm with PDI of 0.263 ± 0.075, zeta potential of 14.62 ± 2.47 mV, and the entrapment efficiency and loading efficiency of 93.14% ± 4.75% and 1.17 ± 0.08%, respectively. In comparison of TP, MC‐PLGA‐TP‐NP showed sustained‐release profile and better transcellular permeability to Caco‐2 cells in vitro. In addition, our data showed that MC‐PLGA‐TP‐NP remarkably reduced the cytotoxicity, attenuated the oxidative stress, and inhibited the increase of the intracellular Ca2+ influx in differentiated PC12 cells induced by Aβ1-42. Therefore, it can be concluded that MC‐PLGA‐TP‐NP is a promising preparation of TP, which exerts a better neuroprotective activity in the AD cellular model.