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71.
72.
Experimental data were compiled for seven soybean varieties studied at four different locations in the U.S. for a period of one to three years. Three dose–response functions (linear, quadratic, and Weibull) were fitted, as appropriate, to the experimental data. Effects of acid deposition on soybean yields were estimated by combining variety-specific dose–response and production data. These calculations suggest that U.S. soybean production (2.2 billion bushels in 1982) would increase by 3.2 million bushels with a 10% reduction in 1982 hydrogen ion concentration levels in all counties where soybeans were grown, and by almost 70 million bushels with uniform improvement to pH 5.2. These estimates are based on many simplifying assumptions and are subject to several important sources of uncertainty explored in this study. The calculated changes are small in comparison with effects from other natural and anthropogenic stresses.  相似文献   
73.
Kinship and Population Subdivision   总被引:1,自引:1,他引:0  
The coefficient of kinship between two diploid organisms describes their overall genetic similarity to each other relative to some base population. For example, kinship between parent and offspring of 1/4 describes gene sharing in excess of random sharing in a random mating population. In a subdivided population the statistic F st describes gene sharing within subdivisions in the same way. Since F st among human populations on a world scale is reliably 10 to 15%, kinship between two individuals of the same human population is equivalent to kinship between grandparent and grandchild or between half siblings. The widespread assertion that this is small and insignificant should be reexamined.  相似文献   
74.
This paper investigates the factors influencing the disposition of cases in juvenile courts. The factors considered are the prior record of the offender, the nature of the offense, the recommendation of the probation officer, and the age of the offender. These four factors are essential components of the juvenile justice system and as such are perceived to be crucial for the understanding of the court's decision. A multivariate analysis of the data is undertaken using the method of log-linear analysis for hierarchical models. In contrast to other studies that have utilized the same method but with fewer variables, the model arrived at in the paper seems to be more accurate and suggests that while the offense and the prior criminal record are quite important factors, their influence on the disposition of cases is greatly bound by the age of the offender and the recommendation of the probation officer.  相似文献   
75.
The potential role of remote sensing in promoting the well-being of human settlements is identified. This was accomplished by formulating a closed loop system for habitat, wherein it requires a continuous feedback between the flow of information derived from remote sensing and the consequences of managerial decisions to control the basic characteristics of the human settlements, e.g. its environment, utilization of resources, early warning of natural hazards, etc. In addition, applications of remote sensing in both global scale and mesoscale for habitat are documented.  相似文献   
76.
Theoretical and practical aspects of dream analysis in family therapy are explored with case examples. The dream is considered tobe a disguised communication and it is used to aid in diagnosis and treatment. The dream is shown to be of special value with families who block communication or only appear to be cooperative. It is used to explore the unconscious elements of family life. Deciphering the dream helps to open new possibilities of communication within the family.  相似文献   
77.
A high-risk population was successfully identified by the use of perinatal screening procedures. These children encountered significantly different parenting practices than the low-risk "control" group. There were also significant differences between "High-Risk" and "Low-Risk" families on issues concerning social adjustment and mother/infant attachment. Five children in a "High-Risk Nonintervene" group required hospitalization for serious injuries thought to be secondary to abnormal parenting practices. There were no such hospitalizations in either a High Risk Intervene group or a Low Risk group. Labordelivery observations, and postpartum interviews and observations provided the most accurate predictive information; prenatal interviews and questionnaires did not add significantly. Perinatal assessment and simple intervention with families at high risk for abnormal parenting practices significantly improves the infants' chances for escaping serious hospitalized physical injury.  相似文献   
78.
79.
Lifetime cancer potency of alfatoxin was assessed based on the Yeh et al. study from China in which both aflatoxin exposure and hepatitis B prevalence were measured. This study provides the best available information for estimating the carcinogenic risk posed by aflatoxin to the U.S. population. Cancer potency of aflatoxin was estimated using a biologically motivated risk assessment model. The best estimate of aflatoxin potency was 9 (mg/kg/day)−1 for individuals negative for hepatitis B and 230 (mg/kg/day)−1 for individuals positive for hepatitis B.  相似文献   
80.
Although much has been learned about the global determinants of physical activity in adults, there has been a lack of specific focus on gender, age, and urban/rural differences. In this church-based community sample of Appalachian adults (N = 1,239), the primary correlates of physical activity included age, gender, obesity, and self-efficacy. Overall, 42% of all participants and 31% of adults age 65 years or older met recommended guidelines for physical activity, which suggests that most participants do not engage in adequate levels of physical activity. Of participants who met physical activity guidelines, the most common modes of moderate and vigorous activity were walking briskly or uphill, heavy housework or gardening, light strength training, and biking. These particular activities that focus on building self-efficacy might be viable targets for intervention among older adults in rural communities.  相似文献   
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