Deleterious results

The solution of 4-chloro-1-methylpiperidine in tetrahydrofuran was dried over calcium hydride at ice-bath temperature prior to use. When the addition of the halide was complete the reaction mixture was refluxed with stirring for one hour. In some subsequent experiments this period of refluxing was omitted with no deleterious result. 

Idoxuridine and congeners are incorporated into DNA with deleterious results. This also applies to the synthesis of human DNA. Therefore, idoxuridine and analogues are suitable only for topical use (e.g., in herpes simplex keratitis). 

On the other hand, the storage stability of biodiesel is adversely affected by the presence of unsaturated alkyl components. The olefinic moieties in biodiesel fuel can undergo oxidative degradation via exposure to air with deleterious results, including formation of solids and gums. The degree of oxidative degradation has been shown to increase with fuel unsaturation. 

The mining of phosphate rock (mostly from terrestrially emplaced marine phosphorite deposits) for use as agricultural fertilizer has increased dramatically in the latter half of this century (F72). In addition to fertilizer use, deforestation, increased cultivation, urban and industrial waste disposal all have enhanced phosphorus transport from terrestrial to aquatic systems, often with deleterious results. For example, elevated phosphorus concentrations in rivers resulting from these activities have resulted in eutrophication in some lakes and coastal areas, stimulating nuisance algal blooms and promoting hypoxic or anoxic conditions harmful or lethal to natural populations (e.g., Caraco, 1995 Fisher et al., 1995 Melack, 1995). 

There are, however, other ways in which conventional drying could, in principle, be performed at temperatures above Tg, without deleterious results. If a solution could be treated so that one or several components can undergo crystallisation, then the crystals formed would serve as a substitute for the subliming ice crystals and could mechanically protect the porous, amorphous matrix against structural collapse. The efficacy of this type of formulation for freeze-drying purposes has been demonstrated for the system water-sucrose-NaCl. " Its practical applications may, however, be limited to products where the bioactive component is not chemically degraded in the freeze-concentrate at temperatures above Tg. 

Electrophoretic deposition is similar to electrochemical plating. But, instead of deposition from solution, particles are deposited from suspension. It is possible to produce thin and thick films of very consistent thickness, even on irregularly shaped substrates, with very short deposition times. Also, the equipment necessary to deposit the films has a relatively inexpensive power supply. However, the films are only physically bonded to the substrate and permanent chemical adhesion must be affected by firing, which can have deleterious results on the mechanical properties of metallic substrates. 

Position 2. It has been shown that the hydroxyl group in position 2 favours the biological effects. Its replacement by a more bulky group has a deleterious result on the potency while its elimination or its replacement by a small group does not change it so much. 

The saturated fatty acids, stearic [57-11-4] and palmitic [57-10-3], are found in animal fats and dairy products. Extensive studies point to the deleterious effect of these acids on arterial walls as a result it is recommended that saturated fatty acid intake be carefully controlled and intake limited (23). 

The deleterious effect of some fat substitutes has been demonstrated in cake frosting (27) the result is an unacceptable frosting, filled with air bubbles. In another example, some low fat cheeses are quite acceptable when cold, but when heated result in a product texture that changes to a sticky, gummy mass. Attempts to replace fat must be viewed as a total systems approach (28,29). It is likely that no one material will replace fats in food rather, replacement will consist of mixtures with each ingredient addressing one or more of the roles played by fats in food. 

Ice formation is both beneficial and detrimental. Benefits, which include the strengthening of food stmctures and the removal of free moisture, are often outweighed by deleterious effects that ice crystal formation may have on plant cell walls in fmits and vegetable products preserved by freezing. Ice crystal formation can result in partial dehydration of the tissue surrounding the ice crystal and the freeze concentration of potential reactants. Ice crystals mechanically dismpt cell stmctures and increase the concentration of cell electrolytes which can result in the chemical denaturation of proteins. Other quaHty losses can also occur (12). 

Sugar is one of the purest foods made, from natural sources, and has never been known to contain any toxic or harmful components. Intensive investigations by the U.S. Food and Dmg Administration resulted in a book in 1986 on the health and safety factors of sugar (cane and beet) in the diet (18). The conclusion was that sugar has no deleterious effect on health in regard to heart disease, diabetes, or other metaboHc disorder. 

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