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61.
We analyzed fifty years of inflation-adjusted data on the Annual Giving program of Princeton University. Most of the variation in both average size of gifts and percentage of class giving can be explained with simple models having three factors: reunion number, class identity, and fiscal year. Besides providing insights into factors influencing donations, these models provide a way to unmask features that are not evident in the raw data, such as trends in giving behavior and exceptional performances by particular classes in particular years.  相似文献   
62.
Abstract

Knowledge and perceptions of Michigan residents about groundwater were assessed so that a comprehensive educational program could be developed and baseline information established to document the program's impact over time. Data were collected from 663 residents in urban, rural, and farm households. Results indicated that knowledge about groundwater was moderate and that a statewide educational campaign on facts about groundwater was necessary. People perceived that land use practices affected groundwater quality at the national, state, and county levels but not at their household level. Significant differences were found among urban, rural, and farm residents and between farmers and nonfarmers in their perceptions of the effects of land use on groundwater quality.  相似文献   
63.
Chronic myeloid leukemia is a myeloproliferative disorder with a unique rearrangement, the Philadelphia chromosome. Oxidative stress, a pervasive condition of an increased number of reactive oxygen species, is now recognized to be prominent feature of various diseases and their progression. Thus antioxidants, which control the oxidative stress state, represent a major line of defense regulating overall true state of health. The relationship between antioxidants status and levels of well-known markers of oxidative stress that are measured as lipid peroxides and oxidized proteins reflect better health indices and postures. The aim of this study was to evaluate the role of oxidative stress in pathophysiology of Chronic myeloid leukemia by measuring the circulating plasma lipid peroxide levels in terms of malonyldialdehyde, total lipid hydroperoxide and oxidized proteins as protein carbonyl whereas antioxidant status were estimated in terms of reduced glutathione and total thiol in plasma of Chronic myeloid leukemia patients. The present study included 47 Chronic myeloid leukemia patients and 20 age-and sex-matched healthy subjects. Out of 47 Chronic myeloid leukemia patients, 31 were in chronic phase (CML-CP) and 16 in accelerated phase (CML-AP). The median age of Chronic myeloid leukemia patients was 33 years and that of controls was 32 years. Oxidative stress and antioxidant status in plasma were evaluated by spectrophotometric procedures. There was a significant increase (p<0.05) in plasma malonyldialdehyde, total lipid hydroperoxide and protein carbonyl levels in Chronic myeloid leukemia patients as compared to healthy subjects. Our results also showed that plasma malonyldialdehyde and protein carbonyl levels were markedly elevated (p<0.05) in both chronic phase (CML-CP) and accelerated phase (CML-AP) as compared to healthy volunteers. Antioxidant status was found to be significantly decreased (p<0.05) in Chronic myeloid leukemia patients and its phases as compared to healthy participants. It could be concluded that oxidative stress may be associated with the pathophysiology of Chronic myeloid leukemia.  相似文献   
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The article highlights the biological significance of songs and calls in birds. The structural diversity of songs and its relevance for social behaviour are described. Acoustic communication plays an important role in the life of birds and has proven useful in establishing phylogenetic and evolutionary relationships among species.  相似文献   
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