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(Table 1) Calculated sea surface temperature of sediment core RC11-210
1988
Pisias, Nicklas G | Rea, David K
Proxy indicators of sea surface temperature and equatorial divergence based on radiolarian assemblage data, and of trade wind intensity based on eolian grain size data show similar aspects of variability during the late Pleistocene: All indicators fluctuate at higher frequencies than the 100,000-year glacial-interglacial cycle, display reduced amplitude variations since 300,000 years ago, exhibit a change in the record character at about 300,000 years ago (the mid-Brunhes climatic event), and have higher amplitude variations in sediments 300,000-850,000 years old. Time series analyses were conducted to determine the spectral character of each record (delta18O of planktonic foraminifer, sea surface temperature values, equatorial divergence indicators, and wind intensity indicators) and to quantify interrecord coherence and phase relationships. The record was divided at the 300,000-year clear change in climatic variability (nonstationarity). The delta18O-based time scale is better lower in the core so our spectral analyses concentrated on the interval from 402,000-774,000 years. The delta18O spectra show 100,000- and 41,000-year power in the younger portion, 0-300,000 years, and 100,000-, 41,000- and 23,000-year power in the older interval, all highly coherent and in phase with the SPECMAP average stacked isotope record. Unlike the isotope record the dominant period in both the eolian grain size and equatorial divergence indicators is 31,000 years. This period is also important in the sea surface temperature signal where the dominant spectral peak is 100,000 years. The 31,000-year spectral component is coherent and in phase between the eolian and divergence records, confirming the link between atmospheric and ocean surface circulation for the first time in the paleoclimate record. Since the 31,000-year power appears in independent data sets within this core and also appears in other equatorial records [J. Imbrie personal communication, 1987], we assume it to be real and representative of both a nonlinear response to orbital forcing, possibly a combination of orbital tilt and eccentricity, and some resonance phenomenon required to amplify the response at this period so that it appears as a dominant frequency component. The mid-Brunhes climatic event is an important aspect of these records, but its cause remains unknown.
Afficher plus [+] Moins [-]Criterios dl sentido de de la inyección en diques | Indicators of the sense of intrusion in dikes
1988
Doblas, M. | Ubanell, A. G. | Gómez Mayor, J.
[Resumen] En este trabajo se establecen una serie de criterios que permite deducir el sentido de la inyección en los diques. Estos criterios son de dos tipos: A) Criterios basados en indicadores cinemáticos de la deformación, que se observan a meso y microescala en los contactos dique-roca de caja, y B) Criterios basados en la observaci6n cartográfica de ciertas variaciones geométricas, texturales, composicionales y de la deformación a lo largo de la dirección de flujo dentro del dique. A su vez, los primeros se subdividen en: 1) EStructuras de flujo magmático. 2) EStructuras miloníticas dúctiles a dúctiles-frágiles. 3) EStructuras frágiles. La deducci6n del sentido de la intrusi6n en los diques tiene gran importancia, tanto para los los esquemas tectónicos regionales, como para el estudio de los flujos magmáticos. | [Abstract] In this paper we study sorne criteria that are useful as indicators of the sense of intrusion in dikes. There are two types of criteria: A) Criteria based on kinematic indicators, which are observable on the meso and microscale, on the dike/host-rock interfaces; B) Criteria based on the cartographical observation of certain geometrical, textural, compositional, and deformational variations along the direction of intrusion of the dikes. The meso and microscale indicators might be subdivided into three main types of structures: 1) Structures of magmatic flow; 2) Ductile to ductile-brittle mylonitic structures); 3) Brittle structures. The deduction of the sense of intrusion in dikes is very important, both for the establishment of regional tectonic schemes, and for the study of magmatic flow patterns.
Afficher plus [+] Moins [-]Microcomputer Based Controller for Flow Regulation of a Chemigation Pump
1988
Thomson, Steven J. | Threadgill, E Dale
A controller based on a single board computer was developed to automatically regulate the amount of chemical applied through injection pumps used with center pivot irrigation systems. User inputs of land area and desired chemical amount to be applied per unit area are used by a BASIC program to calculate proper setting of the pump. Digital control codes are sent by the computer via a D/A converter to set the pump. Under-range and over-range safety indicators are incorporated as well as a user indication of the center pivot's percentage "on" time.
Afficher plus [+] Moins [-]Farm Inspection Scores and Milk Quality Criteria as Indices of Salmonella in Bulk Milk
1988
McEwen, Scott, A. | McClure, Lawrence H. | Martin, S Wayne
The scores from routine dairy farm inspections, bulk milk standard plate bacteria counts, and somatic cell counts from dairy farms with Salmonella-positive milk filters (cases) were compared with those from dairy farms with Salmonella-negative milk filters (controls). Case and control farms showed no significant differences in their inspection scores based on general surroundings of the farm, milking area and cleanliness of milking cows, but differed in the higher mean score for milk houses of case farms. Additionally, there were no differences in the standard plate counts or somatic cell counts between case and control farms. Based on the results of this study, there is no evidence that poor dairy inspection scores, high standard plate counts or high somatic cell counts are useful indicators of the presence of Salmonella in bulk milk supplies from dairy farms.
Afficher plus [+] Moins [-]Effect of a milk-based food supplement on maternal nutritional status and fetal growth in underweight Chilean women
1988
Mardones-Santander, F. | Rosso, P. | Stekel, A. | Ahumada, E. | Llaguno, S. | Pizarro, F. | Salinas, J. | Vial, I. | Walter, T.
Extract: The effects on pregnancy outcome and maternal iron status of powdered milk (PUR) and a milk-based fortified product (V-N) were compared in a group of underweight gravidas. These take-home products were distributed during regular prenatal visits. Women in the V-N group had greater weight gain (12.29 vs 11.31 kg, p less than 0.05) and mean birth weights (3178 vs 3105 g, p less than 0.05) than those in the PUR group. Values for various indicators of maternal Fe status were also higher in the V-N group. Compared with self-selected noncompliers, similar in all control variables to compliers, children of women who consumed powdered milk or the milk-based fortified product had mean birth weights that were higher by 258 and 335 g, respectively. Data indicate a beneficial effect of the fortified product on both maternal nutritional status and fetal growth.(author)
Afficher plus [+] Moins [-]Evaluating the performance of a forest products firm.
1988
Zinkhan F.C.
Financial ratios, such as return on equity, are conceptually imperfect indicators of the overall financial performance of publicly held forest products firms because they are based on accounting data, they ignore risk, and they discourage long-term planning horizons. This article addresses this problem by presenting and analyzing a market value, risk-adjusted approach for evaluating financial performance. The approach is found to produce output that is significantly correlated with return on equity results for a group of forest products firms. However, the financial performance ranking of a notable portion of forest products firms was found to be highly dependent upon the performance indicator used. Since the market value, risk-adjusted approach is more consistent with the shareholder wealth maximization objective than is return on equity, it is recommended for use as an indicator of overall financial performance.
Afficher plus [+] Moins [-]Evaluating the performance of a forest products firm
1988
Zinkhan, F.C.
Financial ratios, such as return on equity, are conceptually imperfect indicators of the overall financial performance of publicly held forest products firms because they are based on accounting data, they ignore risk, and they discourage long-term planning horizons. This article addresses this problem by presenting and analyzing a market value, risk-adjusted approach for evaluating financial performance. The approach is found to produce output that is significantly correlated with return on equity results for a group of forest products firms. However, the financial performance ranking of a notable portion of forest products firms was found to be highly dependent upon the performance indicator used. Since the market value, risk-adjusted approach is more consistent with the shareholder wealth maximization objective than is return on equity, it is recommended for use as an indicator of overall financial performance.
Afficher plus [+] Moins [-]The effects of lime CaOH2 on the performance of wheat cultivars in plinthic ferralsols (eldoret soils) of Kenya
1988
Nyachiro, J.M. (NPBS, Njoro (Kenya)) | Briggs, K.G. (University of Alberta, Edmonton (Canada). Plant Science Dept.)
Seven wheat cultivars (Triticum aestivum L.) were used as indicators of lime response in a greenhouse experiment with a Kenyan Plinthic Ferralsol (Eldoret) which was limed from an initial pH of 5.5 to 6.5 using CaOH2 (calcium hydroxide). Two lime treatments were used: no lime added (control), and the equivalent of 3250 kg/ha of lime added. The analysis of variance (ANOVA) revealed that treatment x cultivar interaction was significant (p less than 0.05) for grain yield, harvest index percentage, and number of seeds per plot. It was demonstrated that the cultivars could be separated into distinct groups based on their relative performance in limed and unlimed soil, and that the degree of response to liming was cultivar dependent. Quantitative relationships between the characters measured, estimated by correlation coefficients, were not significantly affected by the level of lime
Afficher plus [+] Moins [-]Field and Greenhouse Evaluations of Stem Canker Resistance in Soybean
1988
Weaver, D. B. | Sedhom, S. A. | Smith, E. F. | Backman, P. A.
Greenhouse screening using infested toothpicks was compared to field evaluation of soybean [Glycine max (L.) Merr.) breeding lines for resistance to stem canker disease, caused by southern strains ofDiaporthe phaseolorum (Cke. & E11. (Sacc.) var. caulivora Athow and Caldwell (Dpc). Field screenings are reliable indicators of resistance, but often the disease does not develop naturally in field screening nurseries. Thirty-seven random F₄:₆ lines from the cross ‘Hutton’ (susceptible) ✕ ‘Tracy M’ (resistant) were evaluated for their reaction to Dpc in the field (two locations, 2 yr) under natural infestation and infection conditions, and in the greenhouse (three experiments) with artificial inoculation using infested toothpicks. Our objectives were to compare field and greehouse screening and to determine the usefulness of greenhouse inoculation in predicting the yield and disease reaction of breeding lines when these lines were subjected to natural field infection conditions. Field screening based on symptoms and yield was highly effective in identifying resistant genotypes. Heritabilities for yield and disease ratings in the field were 87 and 92%, respectively. The toothpick inoculation procedure used in the greenhouse was effective with each of three Dpc isolates (different in geographic origin from the field location) in identifying the genotypes that showed highest levels of disease resistance in the field. Phenotypic correlations between greenhouse ratings and yield in the infested field ranged from −0.71 to −0.61. Results indicated that selection based on greenhouse screening can be an effective alternative to field screening when resistance is derived from Tracy M. Contribution from the Alabama Agric. Exp. Stn. Journal Series no. 3-871352.
Afficher plus [+] Moins [-]El consumo “per capita” de productos pecuarios en una zona deprimida (Pedroche) | Per capita consumption of animal foods in a depressed area (Pedroche)
1988
Gallego Barrera, J.A. | Mata Moreno, C. | Alcalde Leal, J.L. | Megías Rivas, M.D. | Sánchez Rodríguez, M.
An analysis was made of meat consumption by the inhabitants of a village (Pedroche) situated in a depressed cattle-farming area (Valle de los Pedroches), in order to establish the level of these components in the diet. Consumption was observed to be as much as 12 higher than the national average, pork consumption being substantially higher, and beef, poultry and rabbit consumption lower, since this products are more expensive and less habitually eaten in the area. These findings, based on autoconsumption, may be considered to be a singular compensatory reaction to other standard-of-living indicators in wich the area is highly deficient (services, health care, education, etc.). | Los autores analizan el consumo de productos pecuarios de los habitantes de una población (Pedroche), localizada en una zona ganadera deprimida (Valle de los Pedroches), para determinar el nivel de dichos componentes en su dieta. Se puede observar que el grado de consumo supera a la media nacional en un 12%, aproximadamente, siendo muy superior en productos porcinos e inferior en bovinos, más caros, así como en aves y conejos, de consumo menos habitual en la zona. Estos hechos, basados en el autoconsumo, pueden considerarse como una singular respuesta compensatoria de otros indicadores del nivel de vida en los que son fuertemente deficitarios (servicios, sanidad, enseñanza, etc.).
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