Effects of load mass carried in a backpack upon respiratory muscle fatigue

Purpose: The purpose of this study was to investigate whether loads carried in a backpack, with a load mass ranging from 0 to 20?kg, causes respiratory muscle fatigue. Methods: Eight males performed four randomised load carriage (LC) trials comprising 60?min walking at 6.5?km?h^?1 wearing a backpack of either 0 (LC₀), 10 (LC₁₀), 15 (LC₁₅) or 20?kg (LC₂₀). Inspiratory (P_Imax) and expiratory (P_Emax) mouth pressures were assessed prior to and immediately following each trial. Pulmonary gas exchange, heart rate (HR), blood lactate and glucose concentration and perceptual responses were recorded during the first and final 60?s of each trial. Results: Group mean P_Imax and P_Emax were unchanged following 60-min load carriage in all conditions (p?>?.05). There was an increase over time in pulmonary gas exchange, HR and perceptions of effort relative to baseline measures during each trial (p?p?>?.05). Conclusions: These findings indicate that sub-maximal walking with no load or carrying 10, 15 or 20?kg in a backpack for up to 60?min does not cause respiratory muscle fatigue despite causing an increase in physiological, metabolic and perceptual parameters.     

A dynamic decision model for portfolio investment and assets management

This paper addresses a dynamic portfolio investment problem. It discusses how we can dynamically choose candidate assets, achieve the possible maximum revenue and reduce the risk to the minimum level. The paper generalizes Markowitz's portfolio selection theory and Sharpe's rule for investment decision. An analytical solution is presented to show how an institutional or individual investor can combine Markowitz's portfolio selection theory, generalized Sharpe's rule and Value-at-Risk(VaR) to find candidate assets and optimal level of position sizes for investment (dis-investment). The result shows that the generalized Markowitz's portfolio selection theory and generalized Sharpe's rule improve decision making for investment.     

Social Work Intervention with White Collared Employees and Their Families

This investigation presents a framework for understanding and also to test the efficacy of Social Work intervention on the well being of the white collared employee (industrial employee) and his/her family. A comprehensive and intensive personal- family exploration was done to uncover the relatedness of seemingly disparate areas of the clients lives. A total of 80 executives (industrial employees) served as subjects. A baseline assessment was done using structured, standardized interview-schedules/questionnaires. The results of the study can be enumerated as follows: After the Social Work intervention, the executives in occupational profile, there were significant changes in Role perception, overload, role conflict, low status and poor peer relations. In coping strategies there was significant improvement in sub-scales like problem solving and unproductive coping. Significant reduction was noticed in their proneness to heart disease, depression, inadequate mental mastery, and perceived ill health. There was significant improvement in their family group support, and in their expressiveness, achievement, orientation, active-recreational and organizational characteristics.     

Demand for private supplementary tutoring: conceptual considerations, and socio-economic patterns in Hong Kong

Despite the fact that in some parts of the world private supplementary tutoring is a huge industry with far-reaching economic, social and educational implications, the topic has been neglected by educational researchers. This paper focuses on the nature and determinants of demand for private supplementary tutoring. It first draws on literature from a wide range of countries to identify some conceptual considerations, and then presents data on socio-economic patterns of demand for tutoring in Hong Kong. It highlights the complexity of the topic, and calls for further detailed research in multiple settings.     

父母与孩子在音乐教育中的心理特点及其影响分析

在学习音乐过程中,父母与孩子在音乐教育中存在不同的心理特点与音乐素质。针对不同的心理特点,特别是儿童期心理发展的特点,应采用科学的家庭音乐教育方法,促进儿童心理及智力发展。     

A symplectic eigensolution method in transversely isotropic piezoelectric cylindrical media

INTRODUCTION Since the phenomenon of piezoelectricity in natural crystals was discovered in 1880, it has been applied in many fields, such as smart structure, sensing devices and active control, because of its special properties. Combining electrical behavior with mechanical deformation is the special property which attracted great interest of researchers. Many models have been developed for studying piezoelec- tric effects. Dunn and Wienecke (1996) used Green’s functions for transverse…     

Inexpensive Options for a High-Tech Learning Environment

Radford University was recently configured with a campus-wide wireless local area network. Using these new capabilities, a classroom-based Honors section of Concepts of Biology was conducted solely using electronic technologies (paper was never transferred from professor to student). To accomplish this, students used common software and freeware. Commercial versions of similar software are designed solely for academic use, however, here the students were trained to use software and technologies that will be available to them once leaving the institution. Overall, students in this course responded favorably to the use of technology and reported that it aided in their learning process.