Combinations of effects

Wlrile tire Bms fonnula can be used to locate tire spectral position of tire excitonic state, tliere is no equivalent a priori description of the spectral widtli of tliis state. These bandwidtlis have been attributed to a combination of effects, including inlromogeneous broadening arising from size dispersion, optical dephasing from exciton-surface and exciton-phonon scattering, and fast lifetimes resulting from surface localization 1167, 168, 170, 1711. Due to tire complex nature of tliese line shapes, tliere have been few quantitative calculations of absorjDtion spectra. This situation is in contrast witli tliat of metal nanoparticles, where a more quantitative level of prediction is possible. 

The combination of effects described in item (2) tends to flatten the curves as p increases, but not to the extent that the effect of item (1) disappears. 

Combination of effects of thermal activation and viscous drag then gives for an average dislocation velocity... 

When the polymeric material is compressed the local deformation beneath the indenter will consist of a complex combination of effects. The specific mechanism prevailing will depend on the strain field depth round the indenter and on the morphology of the polymer. According to the various mechanisms of the plastic deformation for semicrystalline polymers 40 the following effects may be anticipated ... 

Colas stimulate digestive juices, and carbonated water speeds the digestion, and this combination of effects, along with the stimulant action of the two alkaloids, can make a big difference to someone who is not feeling well. 

Finally, from the available research into the variety of mechanisms for targetting ophthalmic drugs to specific tissues, means for integrating—both figuratively and literally—combinations of effects are now available [15]. Certainly, the combination of hydrodynamics, retention or sustained release, and diffusional or even active transport can be computed, their influence anticipated, and some specific deficiencies addressed. Nonetheless, many unanticipated interactions may often intrude and still leave the field heavily dependent on empirical assessment. 

Although the reduction of ferricyanide has distinct advantages over the copper deposition reaction, in terms of obtaining a well-defined plateau, its usefulness in free-convection measurements is limited by a combination of Effects (3b) and (3c), as well as its chemical instability (see Section III,B). 

Among the properties measured here, the settling rate is mainly a measure of the size of the floes and in later stages the compressibility of floes and floe networks, and the supernatant clarity is a measure of the size distribution of floes and size dependent capture of the particles and floes by the polymer. The sediment volume and the pulp viscosity on the other hand, are direct measures, not only of floe size and structure but also of adsorbed polymer layers. It is to be noted in this regard that it is this latter aspect which makes it possible to estimate the thickness of adsorbed polymer layers by measuring the viscosity of the medium and the suspension in the presence of polymers (20,21). This combination of effects is another reason one cannot always expect correlation between various flocculation responses. 

Although the effect of nutrients and classical toxicants (e.g. heavy metals, herbicides) is well known, that of the so-called non-PS in biofilms is still largely unknown. Furthermore, the combination of effects, which operate at the basin scale, requires complex approaches. Therefore, the response of biofilms to these situations should trigger the development of new applications and higher standardisation in the use of biofilms. The standardisation of methods and procedures is a challenge for the future research on the use of natural and laboratory biofilms. 

The most effective means to accomplish durable suppression of HIV replication is the simultaneous initiation of combinations of effective anti-HIV drugs with which the patient has not been previously treated and that are not cross resistant with antiretroviral agents with which the patient has been treated previously. 

A burning rate of common materials and products in fire can only be specifically and accurately established through measurement. Estimates from various sources are listed in Table 9.4. Also, oxygen consumption calorimeters are used to measure the energy release rate of complex fuel packages directly. In most cases, the results are a combination of effects ignition, spread and burning rate. 

Like many psychotropic herbs, Kava seems to create its effects by a combination of effects that are mediated by severai of its constituents. To date, at least four mechanisms have been identified that appear to mediate the effects of kava. 

The above examples used to illustrate the specific rules for backward chaining are similar to other attempts at receptor mapping. ) However, these other methods do not account for interactions that may be based on a combination of effects such as hydrophobicity and ligand potency. For instance, a rule that might apply to a compound with a substituted phenyl ring may take the form( ... 

While those work well which have a certain combination of effects at various receptors, ion channels and transporters, others vdth a cleaner profile do not have the same therapeutic effect. 

These combined contraceptives seem to function by inducing feedback inhibition of gonadotrophin secretion which, in turn, inhibits the process of ovulation (Chapter 8). They also induce alterations in the endometrial tissue that may prevent implantation. Furthermore, the progestogen promotes thickening of the cervical mucus, which renders it less hospitable to sperm cells. This combination of effects is quite effective in preventing pregnancy. 

Alcohol Theories include combination of effects at receptor and Pi adernergic agonism leading to GABA receptor sensitization to ethanol Sedation and hypotension with coadministration Caution patients to avoid coadministration Lin et al., 1994... 

Muscarinic stimulants contract the smooth muscle of the bronchial tree. In addition, the glands of the tracheobronchial mucosa are stimulated to secrete. This combination of effects can occasionally cause symptoms, especially in individuals with asthma. The bronchoconstriction caused by muscarinic agonists is eliminated in knockout animals in which the M3... 

No one herbicide will do the job and control all of the many weeds in most fields. Farmers require combinations of effective and dependable herbicides that will work under a wide variety of weed species and densities, soil types, and climatic conditions. Many years of research, trial, error, and experience have been required for farmers to arrive at the greater than 22% of all corn acreage in no-till, and 112.6 million A (45.6 million ha) or more than 40% of our total United States cropland acres in some form of conservation tillage systems in 2004 (CTIC, 2004). Table 33.1 shows the trend toward various types of conservation tillage in recent years. 

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