Variability physiological

Ozone has been shown to initiate many physiological and biochemical changes in sensitive plant species. Decreases in photosynthesis and increases and decreases in respiration have occurred in response to ozonation. The bioenergetic status of mitochondria and chloroplasts is disturbed by ozone. Decreases in oxidative- and photo- phosphorylation have been reported as have increases in adenosine triphosphate and total adenylate content of plant tissue. The variable physiological responses appear to be related to the stage of symptom development at the time of analysis and to the mode of ozone exposure, viz. in vivo and in vitro. 

The consideration of zinc utilization is in large measure an assessment of zinc losses or excretion under any given set of circumstances, including dietary variables, physiological state. 

Environmental and physiological factors controlling the production and/or emission of insect sex pheromones were reviewed by Shorey (5). Light intensity, temperature, host habitat, and air velocity are the main environmental variables. Physiological factors involved are time of day, age, previous experience, population density, diet, hormones and seasonal rhythms. 

Hayashi H (1999) Clinical Application of Hart Rale Variability -Physiological significance. Pathophysiology, Prognosis- Igaku-Shoin, Tokyo... 

Each step ia the method should be iavestigated to determine the extent to which environmental, matrix, material, or procedural variables, from time of collection of material until the time of analysis and including the time of analysis, may affect the estimation of analyte ia the matrix. VariabiUty of the matrix owiag to its physiological nature should be considered. 

A model can be defined as a set of relationships between the variables of interest in the system being investigated. A set of relationships may be in the form of equations the variables depend on the use to which the model is applied. Therefore, mathematical equations based on mass and energy balances, transport phenomena, essential metabolic pathway, and physiology of the culture are employed to describe the reaction processes taking place in a bioreactor. These equations form a model that enables reactor outputs to be related to geometrical aspects and operating conditions of the system. 

Figure 6.5. 5 0 of tooth enamel phosphate versus body size (log scale) for Kenyan fauna analyzed in this study. With the exception of the dikdik, there is a general association between the two variables. In contrast to tbe body-size model (Bryant and Froelicb 1995) wbicb predicts a range of values close to l%o, however, the measured range in 8 0 values for species averages is 5%a. This and the anomalous values for the dikdik reflect physiological and behavioral adaptations by these desert adapted species. 

These data show that both models identify important variables that affect 5 Obody w.ier and 8 Ophospha in mammals. Both serve to identify the dikdik as an outlier which may be explained by their sedentary daytime pattern. On the other hand, the body-size model (Bryant and Froelich 1995), which may reliably predict animal 5 0 in temperate, well-watered regions, does not predict 8 Opho,phaw in these desert-adapted species. The second model (Kohn 1996), by emphasizing animal physiology independent of body size, serves to identify species with different sensitivities to climatic parameters. This, in conjunction with considerations of behavior, indicate that certain species are probably not useful for monitoring paleotemperature because their 5 Obodyw er is not tied, in a consistent way, to The oryx, for example, can... 

The use of protoplasts in studies of stress physiology and biochemistry expands the advantages of cell culture systems discussed in the preceding sections. Additional applications are related to the fusion of protoplasts. Intraspecifie and interspecific protoplast fusion greatly enhance genetic variability of the fused protoplasts (Kumar Cocking, 1987). The resulting somatic hybrids provide cells which can be used for selection of specific traits (e.g. environmental stress tolerance) provided by one or both donor cells and for basic studies on cytoplasmic and nuclear inheritance of desired characteristics. 

The normal range should be established with samples obtained from an adequate sample of healthy persons of specified age and sex. The effect of physiological variables such as activity, eating, menstruation and pregnancy should be known. The confidence limits should be determined with the appropriate statistical tools. Normal ranges determined with hospital patients should be rejected (20 21). 

Instrumentation is also fitted to provide a continuous display of important variables such as temperature and pH, the power used hy the electric motor, airflow, dissolved oxygen and exhaust gas analysis. Manual or computer feedback control can be based either directly on the signals provided hy the prohes and sensors or on derived data calculated from those signals, such as the respiratory coefficient or the rate of change of pH. Mass spectronomical analysis of exhaust gases can provide valuable physiological information. 

Droz PO, Wu MM, Cumberland WG. 1989a. Variability in biological monitoring of organic solvent exposure. II. Application of a population physiological model. BrJ Ind Med 46 547-558. 

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