3,815 research outputs found
The factorization of simple knots
For high-dimensional simple knots we give two theorems concerning unique factorization into irreducible knots, and provide examples to show that the hypotheses are necessary in each cas
Technology transfer potential of an automated water monitoring system
The nature and characteristics of the potential economic need (markets) for a highly integrated water quality monitoring system were investigated. The technological, institutional and marketing factors that would influence the transfer and adoption of an automated system were studied for application to public and private water supply, public and private wastewater treatment and environmental monitoring of rivers and lakes
MODELING THE BODY TEMPERATURE OF HEAT STRESSED HOLSTEIN LYING COWS UNDER TWO DIFFERENT COOLING PROCESSES
Heat stressed cows produce less milk. Thus, a major challenge during hot summer months is to keep the dairy barn at a comfortable temperature. Use of fans is an economical solution but the combination of both spray and fans appears to be an even more effective way to cool cows and improve the milk production than using fans alone. The goal of this study is to recommend an appropriate method for comparing the dynamics of the cooling processes. The first step is to develop a nonlinear model to characterize the thermoregulatory responses of heat stressed dairy cows when they are lying down. The next step is to evaluate methods of comparing treatment effects such as mixed model analysis of the parameter estimates, nonlinear fixed effects analysis, and nonlinear mixed effects analysis. The final step is to illustrate the recommended analysis
Growth and Histological Effects to Protothaca staminea (Littleneck Clam) of Long-Term Exposure to Chlorinated Sea Water
There has been considerable concern about the potential for long-term effects to marine organisms from chlorinated sea water. As part of a larger study to investigate the effects of materials resulting from seawater chlorination on marine organisms, groups of littleneck clams, Protothaca staminea, were exposed to sea water that had been chlorinated. Two experiments were conducted. In one test, groups of littleneck clams were exposed to dilutions of chlorinated sea water that had average chlorine produced oxidant (CPO) concentrations of 16 {micro}g/l or less. In the second test, groups of clams were exposed to chlorinated seawater-unchlorinated seawater mixtures that had target CPO concentrations of 0, 6, 12, 25, 50 and 100 {micro}g/l. In the first experiment, length measurements were made on all clams at approximately one-month intervals for three months. In the second test, length, weight, depth, width and edge etching were used to measure growth, and subsamples were harvested and measured at one-month intervals. In addition, clams were preserved for histological examination. The clams in the first experiment all had negative growth. In the second test, growth was inhibited under all conditions through the first four months of exposure. During the last four months, there was positive signs of growth at the 0, 6 and 12 {micro}g/l CPO test conditions. Histological examination indicates that P. staminea does not adapt well to being held in aquaria. Most clams, tram all test and control conditions, showed evidence of necrosis at one month. This condition seemed to improve with longer exposure at lower CPO concentrations but persisted at CPO concentrations of 25 {micro}g/l and higher. Other histological effects were apparent at the higher exposure concentrations as the length of exposure increased
NONLINEAR MIXED MODELS TO EVALUATE EFFECTS OF ENVIRONMENT CONDITIONS, HAIR COAT, AND ANCHOR LENGTH ON BODY TEMPERATURE DURING AFTERNOON MILKING OF HOLSTEIN COWS IN HAWAII
A hot thermal environment is one factor that causes loss of activity, productivity and even death in cows. One reason may be the effect of hair coat (black or white) on body temperature during different activities and environment conditions. In this study, we attempt to characterize the relationship between body temperature over time using activity, physiological and environmental effects with a nonlinear regression model. The fixed and mixed versions of models are examined. We also examine the effect of the measuring device, anchor length (long or short). Environmental effects, such as, air temperature, thermal heat index (THI), relative humidity, solar radiation, and wind speed, For PM Milking activity, differences in hair coat and anchor length tested as treatment effects. We present a detailed approach focusing on the rate of change in animal body temperature using the nonlinear regression model and investigate how the dynamics between the random-effects changes
The spatial correlates of wildlife distribution around Garamba National Park, Democratic Republic of Congo
Novel DNA methylation profiles associated with key gene regulation and transcription pathways in blood and placenta of growth-restricted neonates
BB/H012494/1/ Biotechnology and Biological Sciences Research Counci
USING FUNCTIONAL DATA ANALYSIS TO EVALUATE EFFECT OF SHADE ON BODY TEMPERATURE OF FEEDLOT HEIFERS DURING ENVIRONMENTAL HEAT STRESS
Heat stress can be a serious problem for cattle. Body temperature (Tb) is a good measure of an animal’s thermo-regulatory response to an environmental thermal challenge. Previous studies found that Tb increases in response to increasing ambient temperature in a controlled chamber. However, when animals are in an uncontrolled environment, Tb is subject to many uncontrolled environmental factors, such as sunshade, wind, and humidity, that increase variation in the data. Hence, functional data analysis (FDA) was applied to analyze the data with uncontrolled environmental factors as curves in the whole series of days in this study. Breed (Angus, MARCIII, MARC-I, Charolais) and availability of shade (access versus no access to sunshade) were included as treatment factors in the statistical model. This study illustrates the potential of FDA to retain all information in the curves. The specific objectives are to use FDA to smooth Tb with large noise, to detect treatment effects on Tb, and to assess the interactions between breed and availability of shade with functional regression coefficients. The results show that FDA can be used to detect significant treatment interactions that may otherwise remain undetected using regular linear or nonlinear models. Significant interactions were found, indicating that access to sun-shade influences the way animals respond to a thermal challenge. Overall, it was found that breeds of cattle with dark-hides were more affected by temperature changes and peak temperatures than breeds of cattle with light-hides. Angus cattle (black) had the highest body temperatures in both shade and no shade areas, while Charolais (white) had the lowest body temperatures in the no shade area. However, MARC III (dark red) experienced the largest temperature differential between shade and no shade. Therefore, breed and availability of shade interactions are important considerations when making predictions to aid in management decisions involving feedlot cattle
The Richness of Contract Law: An Analysis and Critique of Contemporary Theories of Contract Law
The Impact of Exploring Computer Science in Wisconsin: Where Disadvantage is an Advantage
Assessing the impact of regional or statewide interventions in primary and secondary school (K-12) computer science (CS) education is difficult for a variety of reasons. Qualitative survey data provide only a limited view of impacts, but quantitative data can be notoriously difficult to acquire at scale from large numbers of classrooms, schools, or local educational authorities. In this paper, we use several publicly available data sources to glean insights into public high school CS enrollments across an entire U.S. state. Course enrollments with NCES course codes and local descriptors, school-level demographic data, and school geographic attendance boundaries can be combined to highlight where CS offerings persist and thrive, how CS enrollments change over time, and the ultimate quantitative impact of a statewide intervention. We propose a more appropriate level of data aggregation for these types of quantitative studies than has been undertaken in previous work while demonstrating the importance of a contextual aggregation process. The results of our disparate impact analysis for the first time quantify the impact of a statewide Exploring Computer Science (ECS) program rollout on economic groups across the region. Our blueprint for this analysis can serve as a template to guide and assess large-scale K-12 CS interventions wherever detailed project evaluation methods cannot scale to encompass the entire study area, especially in cases where attribute heterogeneity is a significant issue
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