Space-occupying effectiveness

Disorders with space-occupying effect Primary brain tumor Metastatic brain tumor Subdural hematoma (posttrauma) Normal-pressure hydrocephalus Neurosurgical management... 

Mannitol is widely used in patients with primary intracerebral hemorrhage and a depressed level of consciousness to decrease intracranial pressure and alleviate the space-occupying effect of the hematoma in a deteriorating patient, although there is a lack of randomized trials looking at clinical outcomes. 

The proximity effect. This is the simple idea that in an intramolecular reaction the substrate function may be exposed to a larger local concentration of the reagent than in an intermolecular reaction, because the two functions are covalently constrained to occupy adjacent space. This effect has been called the approximation or propinquity effect. The proximity effect certainly seems physically reasonable and is likely to make some contribution to intramolecular reactivity, but it cannot be a major contributor when EM is large, because EM is itself a measure of a presumed local concentration, and the observed large EM values are physically impossible concentrations. The magnitude of rate enhancement achievable by prox-... 

The persistent and distinctive structural features of the GS network effectively reduce crystal engineering to the last remaining (third) dimension. These features prompted our laboratory to synthesize related materials in which the monosulfonate components were replaced with disulfonates. We surmised that this would lead to a two-fold reduction in the amount of space occupied by the organic residues between the GS sheets, creating frameworks... 

As a consequence, in a sensor space of dimension N the effective dimension of the sub-space occupied by the data is less than N. This dimension can be precisely evaluated using algorithms developed to describe dynamic systems. An example is the correlation distance that allows evaluating the fractional dimensionality of a data-set [16]. Correlation distance provides an independent way to evaluate the expected reduction of dimension. 

This aromatic solvent induced shift (ASIS) is explained by the formation of preferential collision complexes or clusters of aromatic solvent molecules in the vicinity of the polar groups of the solute, so that the effect of the solvent magnetic anisotropy within the space occupied... 

R. A. Marcus It is certainly necessary to include all of the reactive trajectories, those that lead to immediate dissociation and those that do not. As Wigner pointed out, in effect, one needs to include all of the phase space occupied by the assumed transition state. Exclusion of any of these trajectories would include part of that phase space. Transition state theory is (classically) an upper bound to the rate since the trajectory may include parts of the TS phase space twice (multiple crossings of the transition state). 

Polyethylene glycol also has a long history of use as an agent for protein precipitation (4). It shares some of the positive attributes of ammonium sulphate in having a low heat of solution and not promoting denaturation of proteins. It appears that after the addition of polyethylene glycol, proteins are excluded from the space occupied by the hydrated polymer, and their effective concentration is increased to a level incompatible with solubility. It is less effective in the purification of IgG but is useful for the isolation of the larger IgM. 

In conclusion, induced, moderate hypothermia can decrease ICP, reduce mortality, and may improve outcome in patients with severe MCA infarction with malignant postischemic brain edema. Important side effects are reduction of platelet count, increased rate of pneumonia, and elevation of serum amylase and lipase levels. The results of our own pilot trial suggest a beneficial effect of moderate hypothermia in the treatment of severe space-occupying MCA infarction. However, our data call for a randomized trial of hypothermia in the therapy of malignant MCA infarction. Whether early hypothermic therapy within the first 6 h after onset of symptoms can reduce infarct size has to be clarified in further clinical trials. 

The fact that weights occupy space creates an interesting problem. The space occupied by a weight is normally occupied by air, and because air has weight, it provides a buoyancy effect (known as Archimedes principle) against the real weight of the object. This effect influences the measured weight of an object. 

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