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Notes on the origin and function of the artiodactyl tarsus | Notes on artiodactyl tarsus Texto completo
1947
Schaeffer, Bobb,
Women's preferences among selected textile products Texto completo
1947
This survey was addressed to the problem of the competitive position of cotton and other fibers in specific end-us markets. Market outlets for household and apparel textiles was largely determined by the actions of ultimate consumers.
Mostrar más [+] Menos [-]The absorption of mineral elements by forage plants. I. The phosphorus, cobalt, manganese, and copper content of some common grasses
1947
Beeson, K.C. | Gray, L. | Adams, M.B.
The phosphorus, cobalt, manganese, and copper contents of 15 grasses grown under uniform conditions in the greenhouse have been determined. Kentucky bluegrass absorbed the highest quantities of all elements except manganese. Timothy proved to be one of the least nutritious grasses as measured by these constituents. Dallis grass, orchard grass, Johnson grass, and red top are intermediate. There was no overall correlation of composition with yield. Grasses of comparable composition have been grouped for survey purposes.
Mostrar más [+] Menos [-]Poliembrionia em citrus Texto completo
1947
Moreira, Sílvio(E. S. A. Luiz de Queiroz em Piracicaba) | Gurgel, J. T. A.(E. S. A. Luiz de Queiroz em Piracicaba) | Arruda, Lineu F. de
The studies on polyembryony in Citrus reported in this paper show that there is a great variability in the degree of polyembryony among the seeds, fruits and trees of a same form or variety of Citrus. Seeds from different crops of the same plant also show considerable variation in the degree of polyembryony. In order to obtain reliable data on the degree of polyembryony in Citrus the samples for study should include a great number of seeds taken from several fruits of different trees. Since there is a yearly variation on the degree of polyembryony it was found necessary to study samples from several crops. The average number of embryos was determined by direct examination of individual seeds. Determinations based on the number of plants developed from every seed always give lower results as many embryos do not grow into seedlings.
Mostrar más [+] Menos [-]Relationship Between Measurements of Air Permeability by Two Machines Texto completo
1947
Landsberg, M.I. | Winston, Gerald
In this paper is described the derivation of the empirical relationship between two commonly used instruments for determining air permeability—namely, the Frazier and Gurley machines. In addition, the limitations of each of the devices are discussed as well as the number of specimens necessary for testing. The correlation has also been determined by consideration of physical constants and pressure differentials, using the empirical data obtained on the Frazier and Gurley instruments operating at a pressure of 0.5 and 1.26 inches of water, respectively. The equations derived were log YF = log 533.0 — 1.02 log X G, based upon the empirical data alone, and log YF = log 507.5 — log XG when the physical constants of the machines were considered.
Mostrar más [+] Menos [-]Wild ducks and coots make good eating
1947
Olsen, Anna Margrethe
"Game rates with meats, poultry and fish as an excellent protein food. The use of all surplus edible game should be encouraged at all times. This bulletin has been prepared to promote the use of surplus wild ducks (number above the breeding stock as determined by the U.S. Fish and Wildlife Service) and the less-known American coot. The coot, erroneously but more commonly known as the mudhen, is neither duck nor chicken. However, because of its similarity to the wild duck in plumage, habitat, food and migratory habits, the coot is often classed with ducks. The material presented in this bulletin is based largely on the experimental work that has been done on game cookery and poultry cookery (Wills, 1946) in the foods laboratories at Iowa State College. Ducks and coots are used interchangeably in the recipes that follow. Duck and coot flavors are similar and not always easily differentiated."--Page [735].
Mostrar más [+] Menos [-]Hemoglobinometria no sul do estado de Minas Gerais (Caxambu) Texto completo
1947
R. Pimenta de Mello
Curvas hemoglobinometricas foram realizadas na cidade de Caxambú (Sul do Estado de Minas Gerais). As determinações em internados do Patronato Agrícola Wencelau Braz - individuos de 8 a 18 anos de indade (11.09 ± 1.10; normal 11.47 ± 0.87), na Empreza de Aguas de Caxambú - homens adultos (12.16 ± 1.21 - normal 13.29 ± 1.19), no Centro de Saude-crianças de ambos os sextos de 5 á 15 anos (11.23 ± 0.95 - normal 11.46 ± 0.96) e mulheres de (11.55 ± 0.98 - normal 11.95 - 1.02), diferença estatisticamente significativa em relação ás curvas padrões pré-determinadas.<br>Hemoglobin determinatios were made in the village of Caxambú (South of Estado de Minas Gerais). Results: Patronato Agrícola Wenceslau Braz (246) - boys from 8 to 18 years old (11.09 ± 1.10 - norma, 11.47 ± 0.87), in Empreza de Aguas Caxambú (100) - men (12.16 ± 1,21-normal, 13.29 ± 1.18) in the Public Health Center (282)-male and female childern from 5 to 15 years old (11.23 ± 0.96-normal, 11.95 ± 1.02). These results showed a significative statistical difference relationship to normal curves (determined in Rio de Janeiro), only in the individuals from the first two places.
Mostrar más [+] Menos [-]The Ih, I, i allels in Hordeum deficiens genotypes of barley
1947
Woodward, R.W.
The deficiens character (designated Vt) for rudimentary floral structures in the lateral florets behaves as an allel of the V, v factor for the two-rowed vs. six-rowed condition, and is at least partially dominant to them. The VtVt genotype is sepitatic to the fertility alleles I, Ih, or i, but when crossed with a VdVdii tester stock the genotypes of these latter factors can be determined. Deficiens varieties with IhIh, II, and ii genotypes were identified by this means. Considerable variation in lateral floret fertility was noted between differences. There also was considerable variation in lateral floret fertility from plant to plant within a given strain and between different heads on the same plant. In several intermediums characterized by having relatively high numbers of lateral kernels, the percentage of lateral kernels was significantly higher in plants grown 6 inches apart in the row than in those seeded at higher rates. The combined data, F2 and F3, from all crosses showed a recombination value of 14.1% +/- 0.36 for the genes VtVd and Prpr. For the more accurate F3 data, when taken alone, this value is 10.1 +/- 1.033.
Mostrar más [+] Menos [-]The clover populations and yields of a Kentucky bluegrass sod as affected by nitrogen fertilization, clipping treatments, and irrigation
1947
Robinson, R.R. | Sprague, V.G.
Clover populations and yields of herbage as affected by two levels of soil moisture, two levels of nitrogen fertilization, and four clipping treatments in all possible combinations were determined on a Kentucky bluegrass sod during 1944 and 1945. The moisture levels were natural rainfall with and without irrigation; the nitrogen levels were no nitrogen fertilization and a very high level of nitrogen fertilization (40 pounds of nitrogen per acre in the early spring and repeated after each clipping); and the clipping treatments included (a) clipping to 1/2 inch when the herbage reached a height of 4 inches, (b) clipping to 1 inch when 4 to 5 inches high, (c) clipping to 2 inches when 5 inches high, and (d) clipping to 1/2 inch when 3 inches high in the early spring and thereafter clipping to 1 inch when 4 to 5 inches high. All plots were limed and well fertilized with phosphate and potash. On plots without nitrogen fertilization or irrigation the closer clipping treatments (1/2 inch and 1 inch) resulted in excellent stands of clover. Clipping to a height of 2 inches produced a more dense sod of grass with considerably less clover. High rates of nitrogen fertilization, without irrigation, greatly decreased the stand of clover and on the plots clipped to 2 inches clover was practically eliminated. With the more severe clipping treatments considerable amounts of clover were maintained even with heavy nitrogen fertilization. On the irrigated plots, clipping to 1/2 inch or 1 inch resulted in excellent stands of clover even on plots that received as much as 360 pounds of nitrogen per acre per year. Fairly good stands of clover were maintained at the 2-inch height of clipping. The highest yields of dry matter were obtained on the plots clipped to 1/2 inches, whereas the lowest yields were obtained on plots clipped to 2 inches. It is concluded that clover populations are determined by the ability of the clover to compete with grass for space, light, moisture, and nutrients. Changes in these factors or of such factors as management practices, winter injury, severe drought, or disease epidemics may greatly change the botanical composition of the pasture. Management practices, particularly as they affect the carbohydrate reserves of the grass, are especially important. It is emphasized that the level of carbohydrate reserves which is best for the grass may not be the best for the pasture. In the present experiment close clipping with ample time for recovery between clipping dates was very effective in maintaining clover. The results obtained in these experiments indicate the need for studies under grazing conditions to determine the possibilities of increasing the clover content and thereby the yields of pastures.
Mostrar más [+] Menos [-]Runoff from pastures in relation to grazing intensity and soil compaction
1947
Alderfer, R.B. | Robinson, R.R.
Runoff losses during the summer from various sites in pastures and grasslands on Hagerstown and Morrison soils were determined by means of a type F rainfall simulator. Water losses were supplemented by measurements of vegetative cover, percentage slope, volume weight, capillary and noncapillary porosity, organic matter content, pH, and the mechanical analysis of the soil. Runoff losses ranged from none to 80% during a 1-hour period in which 1.4 inches of water were applied. In general, water losses were high from heavily grazed pastures, whereas ungrazed areas lost little if any rater due to runoff. The high rate of runoff from the heavily grazed sites was associated with lack of soil cover together with high volume weights and low values for noncapillary and total porosity in the 0 to 1-inch surface soil layer. Compaction was confined to the 0 to 1-inch layer even though this layer contained the greatest amount of organic matter. This is indicated by low volume weights and high noncapillary in the 1- to 3- and 3- to 6-inch soil layers. Since storms of high rainfall intensity are common during the summer months, it is suggested that water loss due to runoff may be an additional factor contributing to the low yields of closely grazed pastures during midsummer.
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