Diurnal patterns

Megaw P., Boelen M., Morgan I., Boelen M. (2006). Diurnal patterns of dopamine release in chicken retina. Neurochem. Inti. 48, 17-23. 

Diurnal Patterns. Radon and its daughter products are known to follow typical diurnal patterns in the outdoors with high levels in the early morning and lower concentrations in the afternoons (Gesell, 1983 UNSCEAR, 1982). Seasonal variation is subject to a variety of geographic and meteorological influence and does not fit a clear-cut pattern. 

Figure 1. Mean diurnal patterns for aerosol concentrations (—o—) and size (—+—) top, and Rn-222 concentrations (—o—) with PAEC (Working Level) (—H— ) bottom, for seven days in September 1985.

T e daily average aerosol concentration is 4060 x 10 particles per m with a fluctuation of + 50 percent based on the standard deviation of the mean. The mean particle size likewise shows large variation with a mean of 0.04 + 0.01 ym. There was some evidence in the aerosol analyzer data for major and minor modes in the size distribution as found by George et al. (1980, 1984). The mean diameter of the particles remained constant as seen in the graph. Both Rn-222 and PAEC (WL) values followed similar diurnal patterns. It is reasonable to expect higher WL levels during the morning due both to increase in radon and aerosol concentrations. The mean diurnal PAEC is 0.006 WL for this seven-day period in September. 

Rat 3.0 mg/kg BW Loss in body weight and disrupted diurnal pattern of drinking and in rearing young after single oral dose, 2-week observation period 16... 

Caldelas, I., Tejadilla D., Gonzalez B., Montufar R. and Hudson R. (2007) Diurnal pattern of clock gene expression in the hypothalamus of the newborn rabbit. Neurosci. 144, 395—401. 

Knights, R. L., D. R. Cronn, and A. L. Crittenden. Diurnal Patterns of Several Components of Urban Particulate Air Pollution. Paper No. 3 Presented at 1975 Pittsburgh Conference on Analytical Chemistry and Applied Spectroscopy, Cleveland, Ohio, March 3, 1975. 

The diurnal patterns of ozone, nitric oxide, and nitrogen dioxide concentrations observed during photochemical oxidant episodes in California have been confirmed by smog-chamber studies. There may be, however, a decrease in reliability with decreasing concentration of values less than 0.1 ppm that were measured by the colorimetric method. The magnitude of these uncertainties among the various monitoring networks in the United States has still to be assessed. 

Concentrations of plasma testosterone and other androgens vary throughout the day in both sexes whether such variation is simply random or fits a repeatable diurnal pattern is a matter of debate. Compared with the diurnal variation seen with cortisol, plasma testosterone concentrations are reasonably constant. Plasma androgen concentrations also vary greatly in women through the menstrual cycle, with peak levels seen in the luteal phase. 

Staudt, M., N. Bertin, U. Hansen, G. Seufert, P. Ciccioli, P. Foster, B. Frenzel, and J.-L. Fugit, Seasonal and Diurnal Patterns of Monoterpene Emissions from Pinus pinea (L.), under Field Conditions, Atmos. Enriron., 31, 145-156 (1997). 

Bushnell P, Evans H. 1986. Diurnal patterns in homecage behavior of rats after acute exposure to triethyltin. Toxicol Appl Pharmacol 85 346-354. 

Aquatic Invertebrates. The initial impact of insecticides on most benthic invertebrates in streams is the inability to maintain their position on the streambed resulting in increased numbers being carried downstream in what is termed drift. Invertebrate drift in treated streams is easily sampled by holding a net in the current. Post-spray catches can be compared to both pre-spray diurnal patterns and catches at an untreated upstream station or in an untreated control stream. This method also can be used to document knockdown of streamside foliage-dwelling or arboreal insects if the net is set so as to sample the stream s surface. Impacts on stream invertebrates can also be determined by caging studies and by pre- and post-spray bottom fauna population assessments which either sample the numbers within a given area of natural streambed (e.g., Surber sampler) or on artificial substrates intentionally set in the stream before treatment to be colonized by resident populations. 

Whiting, G.J., and Chanton, J.P. (1996) Control of the diurnal pattern of methane emission from emergent aquatic macrophytes by gas transport mechanisms. Aquat. Bot. 54, 237-253. 

Peak flow measurement of peak expiratory flow rate (PEFR) on waking, before bed, before and after bronchodilator medication is useful to assess the extent of airflow limitation and the characteristic of the disease in terms of reversibility. There is some evidence of diurnal variability. PEFR is also useful in assessing the disease progression longer term and the response to therapy. Patients are advised to keep an asthma diary and record regularly the peak flows to ascertain their diurnal pattern. 

Laursen, A. E., and Seitzinger, S. P. (2004). Diurnal patterns of denitrification, oxygen consumption and nitrous oxide production in rivers measured at the whole-reach scale. Freshw. Biol. 49, 1448-1458. 

Due to the contrasting diurnal patterns of primary and secondary pollutants, ozone and other secondary pollutants appear to anticorrelate with their precursor species (NO and VOCs) if measured concentrations are plotted for a full diurnal cycle. Peak ozone occurs during and after the time of maximum sunlight, which is also the time of maximum vertical dilution. Concentrations of primary pollutants reach their diurnal minimum at this time. 

Solar illumination Seasonal and diurnal patterns Solar prominence Solar system Solar wind... 

Temporal variations over short time scales have also been accounted for in this model. They are a result of the diurnal pattern of water uptake which peaks at midday and is zero at night. At night, however, the direction of water fluxes can revert, this hydraulic lift being responsible for water efflux from roots at the top of the root system, especially from those roots growing in the topsoil when it dries out (Caldwell et al., 1998). 

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