Impoverishing effects

A large drug manufacturer has decided to study this molecule and formulate it into a drug if it proves to be safe and effective. As an aside, the San Bushmen of the Kalahari desert are currently impoverished and oppressed. If P57 becomes a money-making drug in developed countries, it may mean a better life for people of this tribe, since they will receive royalties (money) when the drug is sold. This drug is very early in the research process and it will be several years before it could be available in the United States. 

In this sense, pesticide and fertilizer use can undermine the goals of lawn care itself, impoverishing the soil and plant health required to maintain turf. This effect, known as the chemical treadmill, emerged vrith the dawn of the green revolution in agriculture in the 1960s. The term was coined to capture the frustrating cycle where increased use of inputs leads to increased demand of the... 

It has been generally held, at least until recently, that a salt dissolved in the liquid phase would enrich the equilibrium vapor in the component in which it was less soluble and impoverish it in the component in which it was more soluble. It was also assumed that the magnitude of the effect on vapor composition depended not only on how much salt was present but also on the degree of difference between the solubilities of the salt in the two liquid components taken separately. Various investigators, including Tursi and Thompson (28) and Fogg (29), have tried to relate the salt effect to this solubility difference alone, but their success... 

In America, opium "dens," places where people came to smoke opium in pipes, were introduced in the West by Chinese immigrants who had been brought to this country as cheap labor to build railroads and work in gold mines. The dens played a central role in the social life of impoverished Chinese laborers. Opium smokers "hit the pipe" as often as three times a day in the dens, where they lay on couches and dreamed off the effects of the drug. 

Some species of lichens are very sensitive to air pollutants. Consequently, urban environments are often highly impoverished in lichen species. Some ecologists have developed schemes by which the intensity of air pollution can be reliably assayed or monitored using the biological responses of lichens in their communities. Monitoring of air quality using lichens can be based on the health and productivity of these organisms in places variously stressed by toxic pollution. Alternatively, the chemical composition of lichens may be assayed, because their tissues can effectively take up and retain sulfur and metals from the atmosphere. 

The effects of upland acidification of freshwaters can be dramatic. Between 1930 and 1975 the median pH of lakes in the Adirondack Mountains of northeastern USA decreased from 6.7 to 5.1, caused by progressively lower pH in rainwater (Fig. 5.7). The acidified lakewater killed fish and other animals by several mechanisms. The problem for fish is that the dissolved Al3+ in the acidic water precipitates as an insoluble Al(OH)3 gel on the less acidic gill tissues, preventing normal uptake of oxygen and suffocating the animal. Similar problems have occurred in Scandinavia and Scotland. In addition to problems in freshwaters, the loss of forests in high-altitude areas has been linked to acid leaching, which leads to impoverishment of soils coupled with direct loss of cations from plant leaves. 

Second, an element must be soluble in water to be available for life. The concentration of the chemical elements in sea water may give us the result of both effects, elemental synthesis in stars and release from the Earth s crust into water (Table 1.1). Table 1.1 also provides information (enrichment E) if a given element has been enriched (or to the contrary) on its way from ancient stars to our sea water and from the Earth s crust to sea water. The term is expressed as the decadic logarithm thus, for example, lg(E) = 2 means a 100-fold enrichment, and lg(E) = — 2 a 100-fold impoverishment. Since the abundance of an element in the universe is compared to that of hydrogen, lg(E) = 0 for H in Table 1.1. 

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