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121.
The relationship between age, relative numerousness judgment, and summation was investigated in 11 Western lowland gorillas (Gorilla gorilla gorilla). Experiments 1 and 2 evaluated the gorillas' ability to select the larger of 2 food quantities before and with training. The majority of gorillas did not reliably select the larger quantity in Experiment 1 until receiving training to do so in Experiment 2. Experiment 3 evaluated their ability to select the larger of 2 pairs of quantities. All gorillas selected the larger pair more often than chance, and the old were less accurate and slower than were the young. For most gorillas, performance in relative numerousness judgment with training and summation was comparable with previous reports in chimpanzees and orangutans. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
122.
The Design of a Human Memory Prosthesis   总被引:1,自引:0,他引:1  
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123.
124.
The effects of time-of-day preferences on selective attention were tested in 2 experiments after normative work with 975 younger adults and 143 older adults verified C. P. May, L. Hasher, and E. R. Stoltzfus's (1993) finding that most older adults prefer the morning, whereas younger adults prefer activities later in the day. In Experiment 1, the cognitive effects of testing at preferred or nonpreferred times of day were examined in negative priming and related paradigms because (a) older adults typically have not shown negative priming and (b) previous research has not taken preference and testing times into account. In contrast to those tested at nonpreferred times, both younger and older groups tested at their preferred times showed negative priming. Age or testing optimality also affected other priming tasks. The central results were replicated in Experiment 2, which tested younger and older adults at their preferred times of the middle of the day. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
125.
Zebra mussels, Dreissena polymorpha, invaded Green Bay, Lake Michigan in the early 1990s. In 1986, prior to zebra mussel invasion, the Green Bay Metropolitan Sewerage District initiated a long-term water quality monitoring program involving 12 stations in three distinct zones along a trophic gradient in lower Green Bay. We analyzed this data set pre and post invasion using various regression models to determine the impacts of the zebra mussel on water clarity, nutrient concentrations, and the relationship between chlorophyll and phosphorus in this system. Following zebra mussel invasion, Secchi depths did not change in all three zones. Chlorophyll a concentrations decreased post zebra mussels in all zones. These differences were attributed to the filter feeding abilities of zebra mussels. Lower Green Bay exhibits a strong trophic gradient and zebra mussel impacts on the chlorophyll-phosphorus relationship differed between the three zones. We saw no changes in the chlorophyll-phosphorus relationship in zone 1, zone 2 appeared to be a transition zone with slight changes in the chlorophyll-phosphorus relationship, and in zone 3 there was evidence of an altered chlorophyll-phosphorus relationship post zebra mussels. These results indicate that the impact of zebra mussels on water quality parameters and on chlorophyll-phosphorus dynamics may differ depending on initial trophic status and on zebra mussel densities.  相似文献   
126.
Gallbladder hypokinesis is an uncommon condition and a potential etiologic factor in the formation of gallstones and the development of cholecystitis. It is associated with a number of different conditions, but gallbladder hypokinesia as a cause of small bowel obstruction is unreported. In the case presented below, we saw a postoperative partial upper small bowel obstruction due to hypokinesia of the gallbladder. The investigations, management, and subsequent recovery are described. A review of the literature failed to reveal any similar occurrence.  相似文献   
127.
The expansion of GP fundholding (GPFH) is central to the British government's attempt to maintain the revolution under way in the National Health Service (NHS). Evaluations of the NHS reforms have portrayed GPFH as an important mechanism for competition, and GPFH's bargaining power is reported to have secured significant changes in health service provision. However, these developments have been acknowledged to be less applicable in relation to community health services (CHS) than acute hospital services. On the basis of case studies of the process of contracting for CHS, GPFHs are shown to display ambivalent and sometimes contradictory views which have to be related to broader policy developments in general practice and primary care. Although this paper focuses on the British situation, many of the issues raised by reforms in primary and community health services have implications for developments in other Western health care systems.  相似文献   
128.
Ten human volunteers completed a 4-month diet series consisting of 1 month each of a control diet, a meatless diet, a high-beef diet, and the same control diet. Fat and fiber contents were essentially the same in all four diets, but protein content was doubled during the high-beef diet. During the 4th week on each diet, three stool specimens collected from each volunteer were analyzed for chemical composition and content of facultative, aerobic, and anaerobic bacteria. The bacteriological data are presented in this paper. High beef protein consumption had little effect on the composition of the intestinal flora. There were no significant differences in total counts of facultative and aerobic or anaerobic organisms in the feces when volunteers were on meatless or high-beef diets. At the species level, when counts during the two control diets were comparable, in only three instances did the change from the meatless to a high-beef diet significantly influence the bacterial numbers. The ratio of mean counts of anaerobic to facultative and aerobic organisms was approximately 15:1 during the meatless diet and 34:1 during the high-meat diet. The data indicate that animal protein consumption has little effect on the fecal bacterial profile in humans.  相似文献   
129.
Management of the hundreds or thousands of requirements associated with a large aerospace system is a tedious, error-prone process. Automated Requirements Traceability System (ARTS) has been developed to automate this process. ARTS is a bookkeeping program that operates on a data base consisting of system requirements and their attributes. It provides upward and downward traceability in a hierarchical structure, as well as data base management and output operations on any requirement-related attributes selected by the user. ARTS is currently implemented on the UNIVAC 1110, DEC VAX-11/780, and IBM computers.  相似文献   
130.
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