ULTRASONOGRAPHIC MEASUREMENT OF ACROMIOHUMERAL DISTANCE IN MANUAL WHEELCHAIR USERS

Subacromial impingement syndrome is one of the most common problems among manual wheelchair users (MWUs). While the mechanism of impingement is associated with the encroachment of subacromial space, few studies have investigated the relationship between space narrowing and intense repetitive wheelchair activities. Ultrasound offers a non-invasive, radiation free, portable, and relatively cost-effective modality to identify acromiohumeral distance (AHD) between acromion and humeral head. We established moderate to excellent intra- and inter-rater reliability and intra- and inter-video reproducibility of the ultrasonographic AHD measurement in 10 MWUs with spinal cord injury and 10 able-bodied individuals in Chapter 2. AHD was significantly impacted while the shoulder was in overhead positions with or without muscle contraction. The effects of repetitive shoulder external rotations between two groups revealed that MWUs group had greater AHD decreases between 45° arm elevation and neutral. In Chapter 3, twenty-three MWUs performed two shoulder muscle-fatiguing protocols. AHD narrowing was detected in holding a weight relief raise compared to a neutral position. AHD was significantly reduced with the electromyography signs of sternal pectoralis major muscle fatigue after multiple weight relief push-ups. In addition, participants who experienced higher shoulder pain scores and perceived exertion after shoulder external rotation fatiguing exercises showed greater AHD narrowing. Chapter 4 investigated if shoulder biomechanics during the start-up phases of propulsion were related to the AHD measurement. Twenty-one MWUs took part in an intense wheelchair propulsion course. Pushing with a technique that resulted in higher shoulder internal rotation moments and lower posterior forces during startup was linked to more acute AHD narrowing. AHD measurements related to shoulder circumference and years since injury. The findings of this research support the clinical practice guideline of reducing overhead shoulder activities and limiting weight relief raises for pressure relief technique to protect the integrity of subacromial space following spinal cord injury. Ultrasonographic measurement of the AHD provides a reliable and direct examination, easy to implement means to identify risk factors for better understanding the mechanisms of subacromial impingement syndrome. This imaging technique may help clinicians to evaluate intervention strategies and exercise prescriptions to minimize the risks for developing subacromial impingement syndrome

ANALYSIS OF FIELDER STARTS AND BENCH ABILITY ON AMERICAN PROFESSIONAL BASEBALL PLAYERS

The development of athletes or players depends on two aspects: nature and nurture. The former is the talent and qualification of the players themselves, while the latter is the training that consumes human, material and financial resources. Take professional baseball players as an example. Matching the talents of players and referring to the relevant starting rules of the professional baseball league, when the up-and-coming players are first discovered, focused training are used on them. By doing so, the value of the players would be effectively enhanced and the players are helped to seek a better way out. This can form a virtuous circle: the pellets get quality players, and the players get better results. That is to say, strengthening the training for the shortcomings of the players with the potential of the starting players can avoid unnecessary training and huge training expenses behind them, and greatly reduce the risk of career, so that the players have higher security in their short career, and get a win-win-win situation. This study is aimed at the schedule information of the American Baseball League teams. Through feature selection of data mining, this study analyzes the main relationships and key differences between starting player and bench player of second baseman and shortstop in League of Nations teams. It is found that the on base percentage and speed of the infielders is an important ability indicator for the starting position; whereas, the second baseman emphasizes on the attack and the shortstop focuses on fielding. This feature is verified by comparing the opinions of experts and commentators.  Article visualizations

General approach of causal mediation analysis with causally ordered multiple mediators and survival outcome

Causal mediation analysis with multiple mediators (causal multi-mediation analysis) is critical in understanding why an intervention works, especially in medical research. Deriving the path-specific effects (PSEs) of exposure on the outcome through a certain set of mediators can detail the causal mechanism of interest. However, the existing models of causal multi-mediation analysis are usually restricted to partial decomposition, which can only evaluate the cumulative effect of several paths. Moreover, the general form of PSEs for an arbitrary number of mediators has not been proposed. In this study, we provide a generalized definition of PSE for partial decomposition (partPSE) and for complete decomposition, which are extended to the survival outcome. We apply the interventional analogues of PSE (iPSE) for complete decomposition to address the difficulty of non-identifiability. Based on Aalen’s additive hazards model and Cox’s proportional hazards model, we derive the generalized analytic forms and illustrate asymptotic property for both iPSEs and partPSEs for survival outcome. The simulation is conducted to evaluate the performance of estimation in several scenarios. We apply the new methodology to investigate the mechanism of methylation signals on mortality mediated through the expression of three nested genes among lung cancer patients

Prevalent Hallucinations during Medical Internships: Phantom Vibration and Ringing Syndromes

Background: Phantom vibration syndrome is a type of hallucination reported among mobile phone users in the general population. Another similar perception, phantom ringing syndrome, has not been previously described in the medical literature. Methods: A prospective longitudinal study of 74 medical interns (46 males, 28 females; mean age, 24.8±1.2 years) was conducted using repeated investigations of the prevalence and associated factors of phantom vibration and ringing. The accompanying symptoms of anxiety and depression were evaluated with the Beck Anxiety and Depression Inventories before the internship began, and again at the third, sixth, and twelfth internship months, and two weeks after the internship ended. Results: The baseline prevalence of phantom vibration was 78.1%, which increased to 95.9% and 93.2% in the third and sixth internship months. The prevalence returned to 80.8% at the twelfth month and decreased to 50.0% 2 weeks after the internship ended. The baseline prevalence of phantom ringing was 27.4%, which increased to 84.9%, 87.7%, and 86.3% in the third, sixth, and twelfth internship months, respectively. This returned to 54.2% two weeks after the internship ended. The anxiety and depression scores also increased during the internship, and returned to baseline two weeks after the internship. There was no significant correlation between phantom vibration/ringing and symptoms of anxiety or depression. The incidence of both phantom vibration and ringing syndromes significantly increased during the internship, and subsequent recovery. Conclusion: This study suggests that phantom vibration and ringing might be entities that are independent of anxiety or depression during evaluation of stress-associated experiences during medical internships

Particle bonding mechanism in CGDS-a three-dimensional approach

Abstract: Cold gas dynamics spray (CGDS) is a surface coating process using highly accelerated particles to form the surface coating by high speed impact of the particles. In the CGDS process, metal particles of generally 1-50 μm diameter is carried by a gas stream in high pressure (typically 20-30 atm) through a DE Laval type nozzle to achieve supersonic flying so as to impact on the substrate. Typically, the impact velocity ranges between 300 and 1200 m/s in the CGDS process. When the particle gains its critical velocity, the minimum in-flight speed at which it can deposit, adiabatic shear instabilities will occur. Herein, to ascertain the critical velocities of different particle sizes on the bonding efficiency in CGDS process, three-dimensional numerical simulations of single particle deposition process were performed. In the CGDS process, one of the most important parameters which determine the bonding strength with the substrate is particle impact temperature. Bonding will occur when the particle’s impacting velocity surpass the critical velocity, at which the interface can achieve 60 % of melting temperature of particle material (Ref 1). Therefore, critical velocity should be a main parameter on the coating quality. The particle critical velocity is determined not only by its size, but also by its material properties. This study numerically investigate the critical velocity for the particle deposition process in CGDS. In the present numerical analysis, copper (Cu) was chosen as particle material and aluminum (Al) as substrate material for this study. The impacting velocities were selected between 300 m/s and 800 m/s increasing in steps of 100 m/s. The simulation result reveals temporal and spatial interfacial temperature distribution and deformation between particle(s) and substrate. Finally, comparison is carried out between the computed results and experimental data

How E-Servqual Affects Customer\u27s Online Purchase Intention?

With the boom of Internet, Internet has become one of the consumers’ online shopping channels. However, there is different in online shopping situation is because of consumers in different cultures and countries have different online shopping behavior is worth to discuss. This study is to explore the Internet users’ online shopping situation in developing country, Malaysia, and 118 questionnaire respondents were collected. Statistical analysis software SPSS 17.0 and AMOS 6.0 were used to analyze the impact on e-service quality, satisfaction, trust, and purchase intention. The model fit of this study was in an acceptable level, and this indicates that the theoretical model of this study supports the description of e-service quality for e-retailers that online shopping situation will be effected by trust and satisfaction. The result of this study will be available for those who interested in developing a transnational e-retailer as a reference, as well as academic research on cross-cultural comparative analysis