Reflectivity variations

Species Tested. In addition to the variation in susceptibiUty to chemically induced toxicity among members within a given population, there may be marked differences between species with respect to the relative potency of a given material to produce toxic injury. These species differences may reflect variations in physiological and biochemical systems, differences in distribution and metaboHsm, and differences in uptake and excretory capacity. 

The actual mass flow rates and speeds are corrected by factor ( /0/ ) and (l/ /0) respectively, reflecting variations in inlet temperature and pressure. The surge line joins different speed lines where the compressor s operation becomes unstable. A compressor is in surge when the main flow through a compressor reverses direction for short time intervals, during which the back... 

Fig. 10-15 Organic carbon fluxes with depth in the water column normalized to mean annual primary production rates at the sites of sediment trap deployment. The undulating line indicates the base of the euphotic zone the horizontal error bars reflect variations in mean annual productivity as well as replicate flux measurements during the same season or over several seasons vertical error bars are depth ranges of several sediment trap deployments and uncertainities in the exact depth location. (Reproduced with permission from E. Suess (1980). Particulate organic carbon flux in the oceans - surface productivity and oxygen utilization, Nature 288 260-263, Macmillan Magazines.)...

Makharia et al., 2005]. These spectra display a major loop in the Z" versus Z plot that cuts the Z axis at some frequency in the range 0.1-1 Hz, followed by an inductive loop that cuts the Z axis again at a much lower frequency. This frequency response of the interfacial faradaic process likely reflects variations of ORR current in response to a cychc potential perturbation, originating from two effects of the potential on ORR rate, which are well resolved by their different response times. A relevant expression describing this behavior is likely of the form... 

Dyn is not yet known, it is likely that such changes reflect variations in the activity of the associated pathways. One possible explanation is that increases in neuropeptide tissue levels are due to decreased release of the transmitter, which dunmishes the extracellular peptide metabolism and results in accumulation of these peptide substances. Another possible contributing factor is a drug-related alteration in neuropeptide synthesis. For example, Bannon et al. (1987) reported that METH administration increased the quantity of striatal messenger RNA for the SP precursor preprotachykinin. Thus, increases in peptide synthesis might contribute to increases in peptide content caused by treatment with METH or the other amphetamine analogs. 

It has been estimated (4) that in most common solvents at room temperature two reactant molecules within a cage of solvent molecules will collide from 10 to a 1000 times before they separate. The number of collisions per encounter will reflect variations in solvent viscosity, molecular separation distances, and the strength of the pertinent intermolecular forces. High viscosities, high liquid densities, and low temperatures favor many collisions per encounter. 

Changes in hydraulic head reflect variation in the hydraulic potential, according to d = pg dh, and hydraulic conductivity is proportional to permeability,... 

Hydrodynamics in the upper GI tract contribute to in vivo dissolution. Our ability to forecast dissolution of poorly soluble drugs in vitro depends on our knowledge of and ability to control hydrodynamics as well as other factors influencing dissolution. Provided suitable conditions (apparatus, hydrodynamics, media) are chosen for the dissolution test, it seems possible to predict dissolution limitations to the oral absorption of drugs and to reflect variations in hydrodynamic conditions in the upper GI tract. The fluid volume available for dissolution in the gut lumen, the contact time of the dissolved compound with the absorptive sites, and particle size have been identified as the main hydrodynamic determinants for the absorption of poorly soluble drugs in vivo. The influence of these factors is usually more pronounced than that of the motility pattern or the GI flow rates per se. 

Figure 16. (a) Ca isotope record from marine carbonates (De La Rocha and DePaolo 2000). The variations are inferred to reflect variations in the isotopic composition of seawater (which is heavier by about 1,4%o). The small excursions of S Ca reflect changes in the global weathering cycle they are recast in (b) in terms of the ratio of the flux of calcium being delivered to the ocean by weathering (Fw) to the flux of Ca being removed from the ocean by carbonate sedimentation (c) Smoothed record of benthic foraminiferal 5 0 for the Cenozoic time period from Zachos et al. (2001). 

The only significant 5 Mo variation in these samples is a small offset of 0.15%o seen between Paciflc and Atlantic crusts, just outside the 2a uncertainties of Siebert et al. (2003). A similar offset is seen in nodule data, although well within the analytical uncertainties of Barling et al. (2001). Such offsets seem unlikely to reflect variations in 8 Mo in seawater in view of the long ocean residence time and relatively invariant seawater concentrations of Mo. Systematic differences in sediment composition may play a role (Barling and Anbar 2004). 

Life is amazing in two senses that, at first glance, seem contradictory life is strikingly diverse life is strikingly unified. The diversity reflects variations on a common, unifying biochemical blueprint. 

So far, 1 have emphasized the amazing diversity of fife forms without saying much about the other side of the coin the unity of fife. Since the key point that I wish to make is that the diversity reflects variations on a common theme, it is time to get to the unity side. 

Figure 20, Reflectivity variations during the etching of a poly-silicon film on an Si02 substrate, (Reproduced with permission from Ref, 110,)...

Variations in density reflect variations in dimensions with those of the bulk density and flow characteristics of the expl, and those of the measured volume. With frequent pellet density determinations and occasional adjustment of the pelleting press, expls with good flow properties can be pressed into pellets reproducible in density to 1% in an automatic pelleting press... 

The activity that characterizes a comet is driven by solar heating. As the comet approaches the Sun, jets of dust and gas erupt from active areas (Fig. 12.1), as they periodically rotate into the sunlight. The nucleus becomes surrounded by a spherical coma formed by the emitted gas and dust. Emitted gas becomes ionized due to interaction with solar ultraviolet radiation, and the ions are swept outward by the solar wind to form the comet s ion tail. A separate dust tail commonly has a different orientation, reflecting variations in the velocities of solid particles and ions. A popular term describing comets is dirty snowballs , although that description probably understates the proportion of rock and dust relative to ices. 

Be should be a useful tracer in detailed studies of atmospheric transport and washout. It is not produced in significant quantities by nuclear tests, and therefore variations in its activity from year to year should reflect variations in atmospheric processes. Several investigators have measured 7Be at different altitudes and latitudes. As the latitude, altitude, and time variations become better known, it should be possible to calculate precisely the rates of vertical and meridional transport and the rates of deposition at the earth s surface. 

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