Physiological maintenance

Handwear has to accommodate the change in length of material required to cover the dorsal aspect (an additional one-quarter, approximately, of the total length of the back of the hand) when a fist is made. A similar accommodation, but not as pronounced, has to be made for the movement of the ankle joint. Analysis of joint rotations and translations can minimise the difference in movement characteristics between the orthosis and body parts. Location of pressure applied to the body is critical to the physiological maintenance of the underlying skin and soft tissues. The use of customising layers between the orthoses enables shear to be accommodated, through a form of suspension. 

Physiological maintenance may be considered in this context to focus on how integrity and performance of the different layers of human tissue canbe maintained, particularly thermal balance. A basic structure of how tissue damage may be avoided will be described. For a soldier the issue of comfort is not a priority however, optimum task performance may be enhanced or maintained through minimising stress caused by discomfort. Discomfort may also be seen as a precursor to more serious issues of blisters or heat stress, for example. 

7 Zones where pressures may be applied effectively on the hand and foot, with the least pressure on nerve branches, blood and lymphatic flow. 

Shear due to dissimilar pressures applied to the body may be minimised through a gradual reduction from high pressure to zero pressure. This may be designed in two equipment platforms. Examples that already incorporate a gradual reduction in interface pressmes include body protectors used by American football players and hip protectors for unsteady elderly patients. The examples given have rounded edges to provide an even transition of loads applied to soft tissues in parallel with the skin of the body surface to the point of no pressure. 

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Anderson, H., K.H. Domsch (1985), Determination of eco-physiological maintenance requirements of soil micro-organisms in a dormant state . Biology and Fertility of Soils, Vol. 1, pp. 81-89. 

Abstract This chapter outlines the substantive issues when designing handwear and footwear for military applications, in the context of the requirements of fit to UK military personnel, their tasks, and the environment or theatre within which they will operate. First, the nature and level of protection in different circumstances are outlined. Second, fit, physiological maintenance, task performance and other factors that influence design are considered. Finally, future trends in design and production are introduced. In each case, best practice from Human Factors and the application of available technologies are described to provide the optimum compromise within a final design solution. 

The reversible oxidation of L-ascorbic acid to dehydro-L-ascorbic acid is the basis for its known physiological activities, stabiUties, and technical apphcations (2). The importance of vitamin C in nutrition and the maintenance of good health is well documented. Over 22,000 references relating only to L-ascorbic acid have appeared since 1966. 

Michelena, V. A. Boyer, J.S. (1982). Complete turgor maintenance at low water potentials in the elongation region of maize leaves. Plant Physiology, 69,1145-9. 

Rowe CL, Kinney OM, Nagle RD, Congdon JD. 1998. Elevated maintenance costs in an anuran (Rana catesbeiana) exposed to a mixture of trace elements during the embryonic and early larval periods. Physiolog Zool 71 27-35. 

Since insomnia is a complex and multifaceted disorder, there is no single pathophysiologic explanation for its various manifestations. Current hypotheses focus on a combination of possible models that incorporate physiologic, cognitive, and cortical arousal. Most insomnia models focus on hyperarousal and its interference with the initiation or maintenance of sleep. 

The body is basically an isothermal system fine-tuned to 37°C (98.6°F). The skin has major responsibility in temperature maintenance. When the body is exposed to chilling temperatures that remove heat faster than the body s metabolic output can replace it, changes take place in the skin to conserve heat. Conversely, when the body becomes overheated, physiological processes come into play that lead to cooling. 

In addition to the classical stress hormones already reviewed, several other hormones are augmented in response to stress. Stress-induced prolactin release is one of the most frequently studied examples. There is no doubt about the causal relationship between stress and increased pituitary prolactin release, but the biological meaning is much less clear (G2). This phylogenetically old hormone has been shown to have more than 85 different functions in all vertebrate species. However, besides its role in the induction of maternal lactogenesis, the physiological importance of prolactin is at present not fully established. Experimental and clinical evidence supports the view that prolactin is also an immunoregulating hormone (M44, R18). Prolactin receptors are present on human T and B lymphocytes (R18), and T lymphocytes depend on prolactin for maintenance of immunocompetence (B19). In addition, it has been shown that prolactin is able to influence the devel-... 

In the normal healthy IVD, the cells not only produce matrix macromolecules and growth factors, they also produce a myriad of proteases [26, 27]. Included in this list of proteases are the matrix metalloproteinases (MMPs) and aggrecanolytic members of the disintegrin and metalloproteinase with thrombospondin motif family (ADAMTS) as well as their respective inhibitors. It is the maintenance of this critical balance that results in a healthy IVD ECM that is subsequently well adapted for its physiologic and biomechanical function. 

Acid-base balance involves chemical and physiological processes responsible for the maintenance of the pH of body fluids at levels that allow optimal function of the whole individual. The ability for the body to regulate pH is critically important in maintaining the operation of many cellular enzymes and the function of vital organs, such as the brain and the heart [143],... 

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