Modern personnel policy and administration as illustrated by the Jordan Marsh Company of Boston

This item was digitized by the Internet Archive. Thesis (M.B.A.)--Boston Universityhttps://archive.org/details/modernpersonnelp00mil

Comparisons of Nitrogen Fertilizer Sources under Kentucky Soil and Climatic Conditions

A summary of yield data comparing different nitrogen fertilizer sources in field experiments conducted by the Agronomy Department staff should provide information that will help answer some of the inquiries regarding the comparative value of some of the nitrogen fertilizers being marketed in Kentucky. Since the nitrogen rates per acre shown in all tables are ACTUAL NITROGEN the COST PER POUND OF NITROGEN in the different materials is an important consideration when evaluating the various products

Manganese Fertilization of Soybeans

Only a small quantity of manganese is essential for plant growth however under certain soil conditions even this is not available to the plant. Depending on severity, manganese deficiency will retard plant growth and may drastically decrease yields. A deficiency of manganese will affect the photosynthesis system of the plant. The visual symptoms of a manganese deficiency on soybeans is interveinal chlorosis of the leaves. The veins remains green until the chlorosis nears the white stage then they also lose their color

Efficiency of Nitrogen Use with Corn on a Tiled and Untiled Soil

Excessive water is one of the largest contributors to the inefficient use of nitrogen in Kentucky. Because of this, nitrogen is often lost by both leaching and,denitrification. The amount, of these losses can be great depending on soil type and weather. Well-drained soils in Kentucky have been shown to lose less nitrogen than poorly drained soils. The nitrogen lost from well drained soils is usually due, to leaching. The nitrogen in the soil, even soon after applying non-nitrate forms of fertilizer N, is mostly in the water soluble nitrate form. When more water falls onto a well-drained soil than the soil can hold, then both water and nitrogen move through the soil below the root zone and are lost for plant use. On poorly-drained soils, the mostly likely method of nitrogen loss is due to denitrification. Nitrogen loss by this mechanism is due to the soil becoming saturated with water (waterlogged) and forcing the air out of the soil. In an effort to survive, some of the microorganisms in the soil take oxygen from nitrate. This process (denitrification) turns the nitrogen into a gas that will diffuse out of the saturated soil and be lost ,into the air. It usually occurs when the soil temperature is above 50°F and the soil is saturated for more than a two day period. If nitrogen fertilizer has been added to the soil prior to the existence of the above conditions, then fairly large amounts of nitrogen can be lost. These conditions are most prevalent in Kentucky on poorly drained soil in April and May. In the past, most farmers have tried to manage this problem by adding excess fertilizer nitrogen to still obtain maximum yields after the loss has been sustained. This management practice may not be economically feasible in the future if nitrogen prices continue to escalate. An alternative management practice used by many farmers is to reduce the amount of nitrogen lost by simply delaying the application of nitrogen until the conditions for denitrification have little chance of occurring. This usually means that the nitrogen is applied in late May or June after the corn has been planted and the risk of waterlogged soil conditions is greatly reduced. To determine the magnitude of such factors, we began an experiment on a poorly drained bottom soil in 1970 to determine 1) the proper rates of preplant nitrogen 2) effectiveness of sidedressing nitrogen and 3) effect of soil tiling on the above two factors

Influence of Time of Application of Nitrogen Fertilizer on Corn Yields

Soil moisture conditions can have a large effect on crop responses to nitrogen fertilization. Kentucky\u27s usual climatic pattern of periods of heavy rainfall and relatively warm temperatures during the winter and spring seasons influences expected yield responses of corn to applied nitrogen. If nitrogen fertilizer is applied in late winter or early spring, some of it may be lost before the plants have made sufficient growth to take up appreciable quantities. The amount of loss that might be expected will be influenced by the amount of rainfall, temperature, amount of organic matter and drainage of the soil

The effects of nicotine on laser Doppler measures of cochlear blood flow

Anesthetized guinea pigs were given arterial bolus injections of saline or varying nicotine concentrations. Blood flow through the cochlea and skin were measured via laser Doppler and arterial blood pressure via an arterial cannula. Cochlear blood flow increased with low doses of nicotine but decreased with the highest dose, while blood pressure increased and skin flow decreased with all doses of nicotine. Control injections of saline vehicle had only minor and transient effects.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/25801/1/0000364.pd

Potential role of angiotensin II in noise-induced increases in inner ear blood flow

Guinea pigs were exposed to 120 dB white noise for 30 min and evidenced a four-fold elevation in plasma concentration of the potent vasoconstricting hormone angiotensin II (AII). Anesthetized animals received intra-arterial injections of All at doses that approximated the endogenous levels measured following noise exposure. A marked decrease in skin blood flow was observed with a concomitant increase in cochlear blood flow as measured by laser Doppler flowmeters. Increased cochlear blood flow appeared to be secondary to the increases in systemic blood pressure induced by AII. These findings suggest that cochlear blood flow may increase during periods of intense noise exposure.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/25806/1/0000369.pd

Weak-Localization and Integrability in Ballistic Cavities

We demonstrate the existence of an interference contribution to the average magnetoconductance, G(B), of ballistic cavities and use it to test the semiclassical theory of quantum billiards. G(B) is qualitatively different for chaotic and regular cavities, an effect explained semiclassically by the differing classical distribution of areas. The magnitude of G(B) is poorly explained by the semiclassical theory of coherent backscattering (elastic enhancement factor)-- correlations beyond time-reversed pairs of trajectories must be included-- but is in agreement with random matrix theory.Comment: 12 pages + 3 figures, revtex, hub-92-w