This article provides an empirical application of Bayesian decision theory to management decisions under uncertainty. The empirical problem is one of choice between contract and independent production of turkeys. The major random variables affecting incomes are product prices and mortality rates. The optimal action is first determined where only prior probabilities of the states of nature are available. Optimal strategies are then determined where a price‐forecasting model is available and posterior probabilities of the states are determined. The value of the additional information provided by the price‐forecasting model is substantial. Simulated growth in firm net worth is faster and more stable when the price‐forecasting model is used.

Composition of the atmosphere of Yolo sandy loam soil columns was determined at different depths and different soil moisture conditions. After saturation with water, soil columns were placed in 30, 25, 20, 15, or 10C constant temperature rooms and moisture was allowed to evaporate from the soil surface. Soil moisture content was determined with a gamma-ray densitometer; CO₂, O₂, and N₂ concentrations were determined by gas chromatography. After 14 days at 30C, moisture tension at the 65 cm depth was 0.1 bar and the soil atmosphere contained 17% CO₂ and 4% O₂. At the 35-cm depth, the moisture was 0.3 bar and the CO₂ and O₂ concentrations were 7% and 14%, respectively. At the 5-cm depth the CO₂ did not rise over 1.5%. At lower temperatures the CO₂ did not rise over 1.5%. At lower temperatures the CO₂ concentrations were less and the maximum was reached more slowly. However, the N₂ concentration increased to almost 90%. At each temperature and all depths, rapid changes occurred in the concentration of gases when the soil moisture tension reached 0.10 to 0.15 bar.

Dioscorea species differ in sapogenin content, tuber size and shape, and virus resistance. The amount and type of sapogenins in tubers of F1 hybrids among four sapogenin-bearing and one other Dioscorea species were determined chromatographically. Characteristics of the tuber and resistance to a virus were observed and compared to those of the parents. The presence of particular sapogenins appeared to be a dominant trait modified by minor genes from either parent. Other traits appeared to be determined by many genes. Heterosis was expressed in some hybrids by superior yields and excellent virus tolerance. Some of the hybrids could be used as clonal varieties, but none contained the desired keto sapogenins except in mixtures with diosgenin.

A method is described for the qualitative and quantitative estimation of four neutral glycosyl ceramides from human plasma and erythrocytes. Total lipids extracted from 50 ml of plasma or packed erythrocytes were separated by silicic acid chromatography into neutral lipids, a fraction of mixed glycolipids that was eluted with acetone-methanol 9:1, and phospholipids. After mild alkali-catalyzed methanolysis to remove contaminants from the crude fraction of glycolipids, individual glycosyl ceramides were isolated by preparative thin-layer chromatography. The oligosaccharide portions of these lipids were characterized by cleavage with methanolic hydrogen chloride and gas chromatography of the O-trimethylsilyl methyl glycosides. It was possible to study the composition of the carbohydrate and sphingolipid base fractions in the same gas chromatographic analysis. With mannitol as an internal standard for gas chromatographic estimation of glucose, concentrations of each of the glycosyl ceramides were determined with a precision of about 10%.Recoveries of the lipids from plasma varied with the complexity of the oligosaccharide moiety and ranged from 94% with glucosyl ceramide to 71% with globoside. Concentrations of the four glycosyl ceramides in plasma and in erythrocytes were determined for samples from young, healthy males. Amounts of glycolipid as low as 0.1 μmole can be determined conveniently by this procedure.

Positional isomers of hexadecenoic aud octadecenoic acids of human adipose tissue have been separated by gas-liquid chromatography and their amounts determined by oxidative cleavage (MnO4 and IO4). The following isomeric octadecenoic acids were present: 7-octadecenoic acid (0.4%), 8- (1.9%), 9- (73.0%), 10- (2.5%), 11- (19.0%) and 12- (3.2%). The hexadecenoic acids have also been shown to be a mixture of positional isomers, in which the cis-9-isomer predominates. 10-Hexadecenoic and 12-octadecenoic acids could conceivably be precursors of linoleic acid.The following branched fatty acids have also been determined in human depot fat: 13-methyltetradecanoic, 12-methyltetradecanoic, 14-methylpentadecanoic, 14-methylhexadecanoic, and 16-methylheptadecanoic acid. They were present in percentages of 0.02-0.6% and their identification rests solely on comparison of their gas-liquid chromatographic retention times with those of synthetic compounds.

Thicknesses of three Mollisols (Tama, Elburn, and Drummer series), developed from Wisconsinan-age material in a toposequence in Central Illinois, were considerably greater (18 to 68 cm) when their lower boundaries were determined by the depth of rooting of native perennial big bluestem (Andropogon gerardi) than when determined by the lower limit of the solum. A combination of four criteria—structural development, significant clay accumulation, significant clay films, and the presence of completely unleached material—probably gave the best measure of solum thickness of these soils. However, evidence of some clay movement below the solums and the greater depth of rooting of native perennial grass, and also of such crops as corn (zea mays L.), suggests that material beneath the solum is important in the behavior, definition, and classification of many of these kinds of soils in the north-central region of the U.S.

Time of green bean pod maturity in the cross between the early-maturing day neutral ‘White Seeded Tendergreen’ and the late-maturing photoperiodic responsive ‘Bush Blue Lake OSU 949-1864’ was determined primarily by a single major gene with lateness being dominant.

The effect of temperature on K-uptake by wheat seedlings was determined. Repressions in K-uptake were found near 15 and 30C. These repressions correspond to changes (higher order phase transitions) in the structure of water and aqueous solutions.

Thirty six soil samples from various soil series of the County of Piracicaba, State of São Paulo (Brazil), were analysed in order to know the permanent charge of the soil colloidal material. Determination of pH was made in soil suspensions prepared with 10 g of soil and 25 ml of distilled water and with 10 g of soil and 25 ml of 1 N KCl solution. Exchangeable aluminum, hydrogen and calcium plus magnesium were extracted with 1 N KCl solution. Aluminum was determined by the "aluminon" colorimetric method and calcium plus magnesium was determined by EDTA titration. Exchangeable calcium, magnesium and potassium were also extracted with 0,05 N HNO3. Potassium was determined by a flame photometer. The covalently bonded hydrogen was extracted with 1 N calcium acetate solution (pH = 7,0) and its determination was performed by titration with 0.02 N NaOH solution, using phenolphthalein as indicator. The permanent negative charge of the studied soils is very low and a very large proportion is neutralized by aluminum in podzolic soils. The 1 N KCl and 0.05 N HNO3 solutions extracted the same amount of calcium plus magnesium indicating the absence of calcium and magnesium silicate and carbonate minerals in the studied soils. The relationship between pH of the soil water suspension is correlated with base saturation in the KC1 system (r = 0.75 and t = 6.58) and is correlated also with the base saturation in the calcium acetate system (r = 0.87 and t = 10.81). The exchangeable aluminum is correlated with the pH determined in soil-water suspension (r = 0.70 and t = 6.40) and with the pH determined in soil 1 N KCl solution suspension (r = 0.81 and t = 6.40). Finally the pH determined in soil water-suspension is correlated to the hydrogen extracted with 1 N calcium solution pH = 7.0 (r = 0.74 and t = 6.43). | O presente trabalho tem por objetivo extrair e determinar diversos íons, como o alumínio, hidrogênio, cálcio e magnésio que se acham ligados aos colóides do solo por eletrovalência, em alguns solos do Município de Piracicaba. Além disso, constitui também finalidade dêste trabalho relacionar as diversas características dos solos estudados a fim de esclarecer vários aspectos considerados importantes na química do solo. Trinta e seis amostras de solos, correspondentes aos horizontes superficiais e subsuperficiais de dez séries do citado Município, foram submetidas à extração com solução 1 N de KCl e no extrato foram determinados os cátions já mencionados, além de determinar o pH em suspensão da solução 1 N em KCl. Nas mesmas amostras foram determinados: pH em suspensão aquosa, carbono total, cálcio, magnésio e potássio extraídos com solução 0,05 N de HNO3 e hidrogênio extraído com solução 1 N de acetato de cálcio com pH = 7,0. Os dados obtidos permitem concluir que a carga negativa permanente dos colóides dos solos estudados é muito baixa e que uma fração elevada da mesma é neutralizada pelo alumínio, em muitas das amostras analisadas. Verificou-se, também, que o teor de alumínio trocável correlaciona-se tanto com o pH determinado em suspensão aquosa, como com o determinado em suspensão de solução 1 N de CKl e com o hidrogênio, extraído com solução de acetato de cálcio 1 N com pH = 7,0. A porcentagem de saturação de bases, calculada em função da carga permanente e a calculada em função da extração das bases com solução de HNO3 0,05 N e da extração do hidrogênio com solução de acetato de cálcio 1N, pH = 7,0, correlacionam-se com o pH do solo. Finalmente, constatou-se que o teor de cálcio mais magnésio extraído com solução 1 N de KCl é equivalente ao extraído com solução 0,05 N de HNO3, indicando que, provàvelmente, os solos estudados não apresentam minerais silicatados ou carbonatados dos mencionados cátions.