Immediate effects

The mechanical properties of wood tend to increase when it is cooled and to decrease when it is heated (6,18). If untreated wood heated in air is not exposed to temperatures of more than - 70° C for more than about 1 year, the decrease in properties with increasing temperature is referred to as immediate or reversible ie, the property would be lower if tested at the higher temperature but would be unchanged if heated and then tested at room temperature. The immediate effect of temperature on strength and modulus of elasticity of clear wood, based on several different loading modes, is illustrated in Figures 4—6 (6). 

Fig. 4. The immediate effect of temperature on the modulus of elasticity of clear wood, relative to the value at 20°C. The plot is a composite of studies on the modulus as measured in hen ding, in tension parallel to grain, and in compression parallel to grain. VariabiUty in reported results is illustrated by the...

Mechanism of Action. THie earliest studies on the mechanism of action of lincomycin showed that lincomycin had the immediate effect on Staphjlococcus aureus of complete inhibition of protein synthesis (23). TThis inhibition results from the blocking of the peptidyltransferase site of the SOS subunit of the bacterial ribosome (24). Litde effect on DNA and RNA synthesis was observed. 

A material may be considered toxic if it has an adverse effect on health. Although it is often not difficult to prove that a material is toxic it is almost impossible to prove that a material is not toxic. Tobacco was smoked for many centuries before the dangerous effects of cigarette smoking were appreciated. Whilst some materials may have an immediate effect, others may take many years. Some toxic materials are purged out of the body and providing they do not go above a certain concentration appear to cause little havoc others accumulate and eventually a lethal dose may be present in the body. 

A serious exposure may also result from a small, single dose over a short period of time and there is no immediate effect. This small dose may exceed t e threshold sensitivity of the individual causing a serious delayed effect. The classic exeimple of this is cancer. 

Doses from several small exposures over a pjcriod of time (chronic exposure) causing no immediate effect, may also result in a delayed effect. This cumulative effect may be serious or minor. 

Another often forgotten aspect of quality management is the behavior of people in an organization. Such behavior is formed by the core values to which that organization subscribes. The absence of core values that form a positive behavior may not have an immediate effect because individuals will operate according to their own personal values. When these conflict with the organization s values, an individual could resent being forced to comply and may eventually adopt the values of the majority or leave to find a more suitable company to work for. 

It is therefore useful to distinguish between active and latent errors or failures. An active human error has an immediate effect in that it either directly causes a hazardous state of the system or is the direct initiator of a chain of events which rapidly leads to the imdesirable state. 

Suppose the system is compressed by pushing down the piston shown in Figure 12.3. The immediate effect is to increase the gas pressure because the same number of molecules are crowded into a smaller volume (P = nRT/V). According to Le Ch telier s principle, the system will shift to partially counteract this change. There is a simple way in which the gas pressure can be reduced. Some of the N02 molecules combine with each other to form N204 (cylinder at right of Figure 12.3). That is, reaction occurs in the reverse direction ... 

N02(p) system at equilibrium. The immediate effect (middle cylinder) is to crowd the same number of moles of gas into a smaller volume and so increase the total pressure. This is partially compensated for by the conversion of some of the N02 to N204, thereby reducing the total number of moles of gas. 

Metabolic Effect Immediate target Immediate effects Tissue... 

If an immediate effect is needed, a loading dose (Dload) must be given to administer the therapeutic amount (Dload = Ao). To maintain the drug effect, the maintenance dose (D) must be administered repetitively with the administration interval (Tau). 

D = Dnorm Cl/Clnorm D = Dnorm Fl/2norm/Fl/2 The administration interval could be selected based on standard peak and trough concentrations or from effect duration time (TED50, TED90). If the dose is reduced, a loading dose (Dload = Cpeak Vd = Dnorm) must be administered to obtain an immediate effect. If Dnorm = const. 

The immediate effect of large amts of moisture on conventional Mil (and commercial) dry expls is to prevent deton. In Engl, to safely store... 

Rate of action. Immediate effect on eyes, effects on skin delayed Vi to 1 hr (Ref 1)... 

Demling, R.H., Katz, A., Lalonde, C., Ryan, P. and Jin, L-J. (1987). The immediate effect of burn wound excision on pulmonary function in sheep. The role of prostanoids, oxygen radicals and chemoattractants. Surgery 101, 44-55. 

The actions of amphetamine are widespread throughout the brain. Amphetamine s immediate effect is to alter the release of monoamines in a dose-dependent manner that is specific for each monoamine transmitter neuronal system. The net effect of amphetamine on monoamine release is complex, with some mechanisms tending to increase monoamine release (e.g., blockade of reuptake and nonimpulsedependent release), and several mechanisms tending to diminish release (e.g., activation of somatodendritic and terminal autoreceptors). 

Cancer is the major latent harmful effect produced by ionizing radiation and the one that most people exposed to radiation are concerned about. The ability of alpha, beta, and gamma radiation to produce cancer in virtually every tissue and organ in laboratory animals has been well-demonstrated. The development of cancer is not an immediate effect. In humans, radiation-induced leukemia has the shortest latent period at 2 years, while other radiation induced cancers have latent periods >20 years. The mechanism by which cancer is induced in living cells is complex and is a topic of intense study. Exposure to ionizing radiation can produce cancer at any site within the body however, some sites appear to be more common than others, such as the breast, lung, stomach, and thyroid. 

Immediate effect on eyes effects on skin are delayed 30 min to 1 h. 

Space and time scales can be combined to draw the distinctions between the risks due to these two types of release. Acute risks are usually associated with immediate effects of a release occurring within hours of the accident and confined to within a few kilometers or less of its location. Examples of this class of events are spills, fires, explosions and their effects such as property damage, traumatic injury, or sudden death. 

The self-similar spectrum is not valid at short times, X < X0, where the details of chemical structure become important (glass transition, entanglements, etc.). The cross-over to the glass transition at short times is typical for all polymeric materials, for both liquids and solids. The critical gel is no exception in that respect. X0 could be used as a characteristic time in the CW spectrum since it somehow characterizes the molecular building block of the critical gel however, it has no direct relation to the LST. At times shorter than X0, the LST has no immediate effect on the rheology. Indirect effects might be seen as a shift in the glass transition, for instance, but these will not be studied here. 

The slow addition of aqueous ammonia solution to an aqueous copper sulfate solution causes an immediate effect on the solubility, since essentially all the Cu2+ ion is consumed by the hydroxide ion of the added reagent, forming in the process a product of very low solubility ... 

Exposure to irritating and lachrymatory agents produces immediate effects. 

Continuous cerebral circulation is required to sustain brain function. Not only does the brain utilize 02 at a very rapid rate, but the brain is absolutely dependent on uninterrupted oxidative metabolism for maintenance of its functional and structural integrity. Even at its maximal rate, anaerobic glycolysis can provide only a small portion of the required energy. Since the amount of 02 stored in brain is extremely small compared with its rate of utilization, the brain requires a continuous supply of 02 from the circulation, and brief disruptions in this supply have an immediate effect on brain function and consciousness. 

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