Diurnal variations

Fig. 4-2. Typical central city diurnal variation in carbon monoxide concentration, in a city in the United States. Spring (------), summer (------), fall (..), winter (----).

A fall in serum is commonly associated with hypokalemic periodic paralysis. Primary hypokalemic paralysis is usually first expressed in children and young adults. Paralytic attacks may fluctuate with remarkable frequency, and there is a common diurnal variation in severity, with weakness especially bad in the morning and evening. The condition has an autosomal dominant pattern of inheritance caused by an abnormality in or close to locus lql3. The gene product is unknown. 

Estuaries exhibit physical and chemical characteristics that are distinct from oceans or lakes. In estuaries, water renewal times are rapid (10 to 10 years compared to 1 to 10 years for lakes and 10 years for oceans), redox and salinity gradients are often transient, and diurnal variations in nutrient concentrations can be significant. The biological productivity of estuaries is high and this, coupled with accumulation of organic debris within estuary boundaries, often produces anoxic conditions at the sediment-water interface. Thus, in contrast to the relatively constant chemical composition of the... 

Wallace JC, Hites RA. 1996. Diurnal variations in atmospheric concentrations of poychlorinated biphenyls and endosulfan implications for sampling protocols. Environ Sci Technol 30(2) 444-446. 

Mantagos, S., Moustogianni, A., Varvarigou, A., Frimas, C. (1989). Effect of light on diurnal variation of blood amino acids in neonates. Biol. Neonate 55, 97-103. 

A. Walter, A. Pich, G. Scholz, H. Marschner, and V. Rdmheld, Diurnal variations in release of phytosiderophores and in concentrations of phytosiderophores and nicotianamine in roots and shoots of barley. J. Plant Physiol. 147 191 (1995). 

Assessment of diurnal variation of PEF may be useful in patients who have asthma symptoms and normal spirometry. When spirometry is equivocal, a 20% or greater decrease in FEV after the administration of methacholine is diagnostic for asthma. A negative bronchoprovocation test with methacholine may help rule out asthma. 

Some physiological variables influence the measurement of fibrinolytic activators and inhibitors. For instance, both t-PA and plasminogen activator inhibitor 1 (PAI-1) levels in plasma are subject to diurnal variation in a 12-hour period. Even in samples taken at the same time of day the coefficient of variation (CV) of measured PAI levels range from 8 to 143% To account for this diurnal variation, blood samples spaced over several time intervals during a 24-hour period should be collected. Consumption of alcohol induces the PAI level in plasma. The half-life of t-PA is 360 seconds. However, in the presence of trauma or inflammation, when the PAI-1 level is expected to be elevated 10-fold, the half-life of t-PA is reduced to 36 seconds (114). 

Chen D, Bi X, Zhao J, Chen L, Tan J, Mai B, Sheng G, Fu J, Wong M (2011) Pollution characterization and diurnal variation of PBDEs in the atmosphere of an E-waste dismantling region. Environ Pollut 157 1051-1057... 

Figure 7.2 Diurnal variation of extracellular dopamine in the non-human primate putamen. Dopamine concentrations (dm) as determined by high-pressure liquid chromatography of microdialysates obtained from the putamen of two rhesus monkeys across their 12 12 h lights-on (waking 7 00 am 7 00 pm) and lights off (sleep 7 00 pm-7 00 am) periods. Ten minute samples (2 pl/min sampling rate) were derived from nine individual 8 h sessions in each animal in which the sleep-wake state was monitored simultaneously by standard electrophysiological parameters.

Matsumoto M., Kimura K., Fujisawa A. el al. (1981). Diurnal variations in monoamine contents in discrete brain regions of the Mongolian gerbil (Meriones unguiculatus). J. Neurochem. 37, 792-4. 

However, the question must always be asked as to whether these processes could have taken place on the primordial Earth in its archaic state. The answer requires considerable fundamental consideration. Strictly speaking, most of the experiments carried out on prebiotic chemistry cannot be carried out under prebiotic conditions , since we do not know exactly what these were. In spite of the large amount of work done, physical parameters such as temperature, composition and pressure of the primeval atmosphere, extent and results of asteroid impacts, the nature of the Earth s surface, the state of the primeval ocean etc. have not so far been established or even extrapolated. It is not even sure that this will be possible in the future. In spite of these difficulties, attempts are being made to define and study the synthetic possibilities, on the basis of the assumed scenario on the primeval Earth. Thus, for example, in the case of the SPREAD process, we can assume that the surface at which the reactions occur could not have been an SH-containing thiosepharose, but a mineral structure of similar activity which could have carried out the necessary functions just as well. The separation of the copy of the matrix could have been driven by a periodic temperature change (e.g., diurnal variation). For his models, H. Kuhn has assumed that similar periodic processes are the driving force for some prebiotic reactions (see Sect. 8.3). 

The model was forced with agricultural application data of the insecticide DDT compiled by Semeena and Lammel (2003). Statistical data of DDT consumption reported by member of the UN states to Food and Agriculture Organisation (FAO) were combined with other published data (details in Semeena and Lammel (2003)). The emission inventory assumed 100 % of p,p -DDT. After scaling the DDT consumption with crop land distribution, the data were extrapolated to the model grid. The result was a data set with spatially and temporally varying applications (accumulated application and temporal evolution shown in Figure 3.1). No seasonal or diurnal variation of the applications is considered. 

The effective surface temperature of Titan is 98 K and the atmosphere is nearly completely nitrogen. Calculate the scale height for Titan s atmosphere. Comment on the diurnal variation of the scale height and the variation with altitude. 

Desynchronization of circadian or seasonal rhythms cause diurnal variations in mood and sleep patterns and can result in seasonal recurrences of mood episodes. 

The anaerobic residence time of the wastewater during transport is a factor that affects the level of sulfide concentration in the wastewater. The residence time in a pressure pipe is determined by the magnitude of wastewater inflow compared with the volume (length and diameter) of the pipe. The level of sulfide formation in a given pipe is subject to the diurnal variation of the inflowing... 

FIGURE 6.3. Diurnal variation in the sulfide concentration of a 4 km pressure main located in North Jutland, Denmark. The typical variation of the residence time during a dry-weather period is between 6 and 14 hours, corresponding to the daily wastewater flow. During a rain event, the residence time may be reduced to about 1 hour. 

Figure 4. Sketch of the diurnal variation in the concentrations of nitrogen oxides, hydrocarbons, ozone and aldehydes under conditions of photosmog (Manahan, 1994).

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