Mechanisms responsible for producing

Figure 3. Mechanisms responsible for producing natural charge on particles. (Adapted from reference 18. Copyright 1995 Academic.)...

The overall extraction process is sometimes subdivided into two general categories according to the main mechanisms responsible for the dissolution stage (/) those operations that occur because of the solubiHty of the solute in or its miscibility with the solvent, eg, oilseed extraction, and (2) extractions where the solvent must react with a constituent of the soHd material in order to produce a compound soluble in the solvent, eg, the extraction of metals from metalliferous ores. In the former case the rate of extraction is most likely to be controUed by diffusion phenomena, but in the latter the kinetics of the reaction producing the solute may play a dominant role. 

Acetone is a coproduct of butane LPO. Some of this is produced from isobutane, an impurity present in all commercial butane (by reactions 2, 13, 14, and 16). However, it is likely that much of it is produced through the back-biting mechanisms responsible for methyl ketone formation in the LPO of higher hydrocarbons (216). 

Studies on muscle contraction carried out between 1930 and 1960 heralded the modem era of research on cytoskeletal stmctures. Actin and myosin were identified as the major contractile proteins of muscle, and detailed electron microscopic studies on sarcomeres by H.E. Huxley and associates in the 1950s produced the concept of the sliding filament model, which remains the keystone to an understanding of the molecular mechanisms responsible for cytoskeletal motility. 

The mechanisms responsible for inhibited oxidation depend on the experimental conditions and particular properties of RH and antioxidant (see earlier). Let us assume that hydroperoxide is relatively stable, so that it virtually does not decompose during the induction period (kdr -c 1). Actually, this means that the rate of ROOH formation is much higher than the rate of its decomposition, / 2[RH] [RO]2 ] 3> d[ROOH]. For each of the mechanisms of inhibited autoxidation, there is a relationship between the amounts of the inhibitor consumed and hydroperoxide produced (see Tablel4.2). For example, for mechanism V with key reactions (2), (7), (—7), and (8), we can get (by dividing the oxidation rate v into the rate of inhibitor consumption) the following equation ... 

Clinical pain is characterized by the presence of spontaneous pain or hypersensitivity to pain-provoking stimuli. Hypersensitivity includes pain produced by low-intensity stimuli that normally only elicit an innocuous sensation (allodynia), or an exaggerated response to a noxious stimulus (hyperalgesia). There are two distinct forms of clinical pain, the pain that occurs after tissue injury or inflammatory diseases (inflammatory pain) and the pain associated with a lesion or disease of the nervous system (neuropathic pain). Although the mechanisms responsible for the initiation and maintenance of these pains differ, they are both characterized by heightened... 

The mechanism responsible for releasing the contents of lysosomes is not yet known. According to one hypothesis (Ollinger and Brunk, 1995), the membranes of lysosomes are damaged during apoptosis induced by oxidative stress, possibly due to diffusion of intracellularly produced hydrogen peroxide into these organelles. Inside the lysosomal apparatus. 

Although exit channel effects are capable of producing a range of non-Boltzmann population distributions, the wavelength dependence of the kinetic energy provides an indication that nonthermal activation is responsible for the fast component of the desorption signal. The activation mechanism responsible for this desorption process is not determined from these experiments, but will be re-addressed in section 4.6. 

Granting that precise mechanisms responsible for the characteristic anticancer activity and mammalian toxicity of vinblastine, vincristine, and related compounds have not been rigorously established, it nevertheless is important to describe representative biological and biochemical actions of the drugs that may have mechanistic pertinence. The susceptibility to mitotic spindle dissolution of cell lines with 100-fold differences in sensitivity to vinblastine has been investigated 14). There was an excellent correlation between drug concentrations required to produce inhibition of cell colony formation and those required to dissolve mitotic spindles. It is noteworthy that effects on the mitotic spindle of vinblastine occur very rapidly and can be detected within 30 sec. 

Propranolol and other p-blockers also have been shown to produce an increase in oxygen supply to the subendocardium of ischemic areas. The mechanism responsible for this effect is most hkely related to the... 

The replacement of cement with silica fume results in reduced air contents in the fresh concrete compared to control concrete containing no silica fume. Achieving the required air content necessitates an increase in the AKA dosage, but the AEA demand decreases in the presence of a WRA or SP. There is also an evident increase in SP and WRA amounts required to produce desired modifications in the presence of silica fiune. The mechanisms responsible for such effects are described as follows. 

All of the SSRIs also show a flat dose-response curve, meaning that there is usually no advantage to increasing the dose above that which is the usually effective minimum dose. Of interest, the four SSRIs marketed as antidepressants in the United States at their usual effective therapeutic dose (i.e., 40 mg per day for citalopram, 20 mg per day for paroxetine and fluoxetine, and 50 mg per day for sertraline) produce comparable effects on either plasma serotonin levels or the serotonin uptake pump in platelets (25). These results are consistent with the conclusion that serotonin uptake inhibition is the mechanism responsible for the antidepressant efficacy of these agents. 

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