Regional differences

Becomes difficult (may requite many stages or reflux) when temperatures of high and low boiling nodes of region differ by <10° C. 

Attack associated with nonuniformity of the aqueous environments at a surface is called concentration cell corrosion. Corrosion occurs when the environment near the metal surface differs from region to region. These differences create anodes and cathodes (regions differing in electrochemical potential). Local-action corrosion cells are established, and anodic areas lose metal by corrosion. Shielded areas are particularly susceptible to attack, as they often act as anodes (Fig. 2.1). Differences in concentration of dissolved ions such as hydrogen, oxygen, chloride, sulfate, etc. eventually develop between shielded and nearby regions. 

Fig. 13.5. Schematic representation of the potential energy surfaces of the ground state (S ,) and the excited state (.5,) of a nonadiabatic photoreaction of reactant R. Depending on the way the classical trajectories enter the conical intersection region, different ground-state valleys, which lead to products P and can be reached. Reproduced from Angew. Chem. Int. Ed. Engl. 34 549 (1995) by permission of Wiley-VCH.

The main region of interest for analytical purposes is from 2.5 to 25 fim (micrometres), i.e. 4000 to 400 wavenumbers (waves per centimetre, cm-1). Normal optical materials such as glass or quartz absorb strongly in the infrared, so instruments for carrying our measurements in this region differ from those used for the electronic (visible/ultraviolet) region. 

Values of the general d function in the x, y, and z directions are shown in Figure 1 as a function of a. The functions in each region differ from those in the other two regions by at most a phase factor, —1, and a rotation, which serves to permute the variables x, y, and z. 

Kawagoe, J., Abe, K., Kogure, K. (1993). Regional difference of hsp70 and hsc70 heat shock mRNA inductions in rat hippocampus after transient global ischemia. Neurosci. Lett. 153, 165-168. 

Most variation in human 5 C values in Europe is related to regional differences in climate most of the variation in 5 N seems to be caused by variable consumption of animal protein, combined with poorly understood variation in plant nitrogen values. Finally, we also conclude that the causes of slightly high 5 N values in humans are not yet well-understood. 

Bowerman, W.M., Best, D.A., and Giesy, J.P. et al. (2003). Associations between regional differences in PCBs and DDE in blood of nestling bald eagles and reprodnctive prodnctiv-ity. Environmental Toxicology and Chemistry 22, 371-376. 

SALIH M A, SIMS s H and KALU D N (1996) Putative intestinal estrogen receptor evidence for regional differences. Mol. Cell Endocrinol. 121, 47-55. 

Steidl RJ, Griffin CR, Niles LJ. 1991. Contaminant levels of osprey eggs and prey reflect regional differences in reproductive success. J Wildl Manage 55 601-608. 

In anesthetized rats, amphetamine causes dose-dependent changes in neostriatal unit activity. Spontaneously aetive neostriatal cells are uniformly inhibited at low (<2.0 mg/kg, IP) doses. At intermediate doses, an initial exeitation precedes the inhibition, and, at high doses (>5.0 mg/kg, IP), the predominant effect is excitation (Groves and Rebec 1976). Regional differences in the direction, magnitude, and duration of the response of neurons in the neostriatum exist (Rebee and Curtis 1983). 

Blue, M.E. Kosofsky, B.E. and Molliver, M.E. Regional differences in the serotonin innervation of rodent cerebral cortex Differential distribution of two morphologically distinct axon types. Abstr Soc Neurosci 14 209,... 

Pesticide concentrations in earthworms displayed regional differences. Such differences are likely to be observed in other potential food items. Earthworm exposure was log-normally distributed with the highest concentration being 163 qgg which represents the 97th percentile of diazinon found in earthworms from all sites. The geometric mean diazinon concentration in earthworms from PA was 2.56 agg (CL95 = 1.62. 06qgg ), and from WA was 0.046 xgg ... 

Total caffeine consumption will vary with a number of factors that are often difficult to disentangle. For caffeine exposure attributable to coffee, this includes brewing method and preparation type of coffee (Arabica, Robusta, instant), averaging to 1.3% caffeine for roasted beans 39 brand of coffee size of coffee cup and the volume of added ingredients, such as milk, cream sweeteners, and syrups. There are several different brewing or preparation techniques by which coffee can be prepared. Most notably, they differ in their final extraction of caffeine depending on the process. Filter coffee or automatic drip coffee results in approximately 97 to 100% caffeine extraction 37 however, regional differences in the volume of coffee... 

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