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Basking is a behaviour frequently observed in the rock hyrax (Procavia capensis) during winter that supposedly plays a significant role in rewarming from nocturnal hypothermia. This behaviour, together with changes in body temperature and changes in black bulb temperatures (Tbb) were investigated in the natural environment. In this study, rock hyraxes did not reduce their body temperature substantially overnight and thus basking was not used for rewarming but rather to maintain constant body temperatures under low ambient conditions. Frequency of basking changed throughout the day as Tbb increased and decreased. Different basking postures (hunched or flat), orientations to the sun and basking bout lengths were modified depending on Tbb experienced. There was no difference in body temperature between the two basking postures at any Tbb. It appears that rock hyraxes did not use basking behaviour as a way of warming up afternight-time but used it during the day as a diurnal energy conserving mechanism.Key words: rock hyrax, basking, orientation, posture, black bulb temperature, body temperature, behaviour.

The behavioural use of rock crevices by rock hyraxProcaviacapensis was essential in avoiding harsh environmental conditions during summer. Foraging was the most dominant above-ground behaviour exhibited by rock hyrax during summer. Most ambient temperatures in the early morning of summer fell within the rock hyrax thermoneutral zone, which enabled the animals to forage without the need for prior heating from a solar energy source. Basking was an essential behaviour displayed by rock hyrax in winter. The low quality and scarce food source may be inadequate to meet the metabolic requirements of rock hyrax at low ambient temperatures. It therefore seems that basking is not only an energy conservation mechanism but also essential for the survival of rock hyrax during winter. Juvenile rock hyrax have a higher surface area to volume ratio and are more vulnerable to low ambient conditions than adults. As a result they displayed a different behaviour pattern to adult rock hyrax during winter. Juveniles required larger amounts of food to meet their energetic requirements, while adults spent greater amounts of time basking. The extent to which rock hyrax meet energetic requirements depends on the interaction of ambient temperature, food availability, food quality and foraging efficiency in the presence of predators. The extent to which each of these factors influenced behaviour differed on a daily and seasonal basis.

Project Chrysalis was a school-based program that provided services to female adolescents with histories of physical, sexual, or emotional abuse. Young women (14-17 years of age) were enrolled and assigned randomly either to a program or to a control condition. It was found that participation in Project Chrysalis was associated with outcomes such as healthier beliefs and attitudes about alcohol and other drug use and reduced initiation of tobacco and marijuana use. Participants also had fewer suicidal ideations and behaviors. It was shown that older participants (16 and 17 years of age) were less likely to attend Project Chrysalis activities than were younger participants and that the prevalence of depression and risk for suicide was higher among younger participants. That indicates that enrolling younger participants (11 through 14 years of age), before negative attitudes and behaviors have begun, might produce stronger positive effects.

Several synthetic nucleoside analogues, including AZT(RETROVIR), ddC (HIVID), ddI (VIDEX), and d4T (ZERIT), are currently being used in the treatment of HIV infection. Unfortunately, in clinical use the appearance of severe and sometimes debilitating peripheral neuropathy and pain has been associated with the long-term use of several of these drugs (i.e., ddC, ddI and d4T), although not with AZT. To date, standard pre-clinical animal toxicity studies have failed to reveal any adverse neurologic effects of these compounds. However, previously reported preliminary findings suggest that ddC may alter several neuro-behavioral parameters (including locomotor activity, acoustic startle responding, and aggression) in rats and mice following presentation in the animals' drinking water for 7 days. The current series of experiments examined effects of acutely administered ddC and AZT on spontaneous locomotor activity and acoustic startle responses (with and without pre-pulse) in female Sprague–Dawley rats. Following intragastric administration, ddC reduced locomotion at all but the highest dose, whereas AZT had no significant effect on locomotor activity. Acutely administered ddC had no effect on ASR, whereas AZT increased ASR at the highest stimulus intensity. These data support the use of behavioral testing in the development of the antiviral nucleoside analogues, as behavioral testing may be more effective in identifying the neurologically active agents than is standard toxicity testing. Published by Elsevier Science Inc., 1997

1996). In most cases, in a wide variety of species(including passerines such as flycatchers, warblers, robins,etc. and non-passerines such as owls, raptors, penguins,waders, ptarmigan, geese, ducks, etc.), parents increaseintensity of nest defence over the nesting period (Hamer andFurness 1993, Martin and Horn 1993, Sproat and Ritchison1993, Forbes

Two experiments examined the effects of age, genetic strain, and nicotine on acoustic startle response (ASR) amplitude and prepulse inhibition (PPI) in rats. ASR amplitude measures reactivity to external stimulation, and PPI is used as an index of sensory gating related to attention. Both ASR amplitude and PPI have been previously reported to be increased by nicotine in adult rats. Experiment 1 examined effects of chronically administered nicotine and saline on ASR and PPI in Wistar, Long-Evans, and Sprague-Dawley rats (40 days of age). Experiment 2 examined the effects of chronically administered nicotine and saline in Sprague-Dawley rats of two age groups: 40 and 70 days of age at the beginning of the study. ASR amplitude differed significantly across strains with the values for Wistar > Sprague-Dawley > Long-Evans, and there were no differences in percent of PPI among the three strains. In addition, results of Experiment 2 indicated that older rats had significantly greater ASR amplitudes and PPI than younger rats. Consistent with previous reports, nicotine increased ASR and PPI in the older rats; however, there were no significant differences in the younger rats. Therefore, age and genetic strain are important variables in the analysis of nicotine's effects on startle behaviors in rats.

The incidence of cervical cancer has decreased over 70% in the last several decades due in large part to the Papanicolaou (Pap) test. Despite the acknowledged efficacy of this test, however, many women do not receive cervical screening. The present study investigated the contributions of individual differences in concerns with self-presentation and social evaluation to the prediction of intentions and behavior involving cervical screening. Eighty-two Caucasian women completed measures of social anxiety, physique anxiety, public and private self-consciousness, fear of negative evaluation, and self-esteem, in addition to questions assessing their knowledge and behavior regarding cervical screening. Social anxiety significantly predicted intention to receive cervical screening for a medical reason, as well as the frequency with which the women actually received gynecological examinations. Physique anxiety accounted for a significant percentage of the variance in women's likelihood of receiving cervical screening within the next year. Interpersonal aspects of the gynecological exam, as well as implications of the findings for gynecological practice are discussed.

Rock hyrax (Procavia capensis) are faced with large daily fluctuations in ambient temperature during summer and winter. In this study, peritoneal body temperature of free-living rock hyrax was investigated. During winter, when low ambient temperatures and food supply prevail, rock hyrax maintained a lower core body temperature relative to summer. In winter body temperatures during the day were more variable than at night. This daytime variability is likely a result of body temperatures being raised from basking in the sun. Body temperatures recorded during winter never fell to low levels recorded in previous laboratory studies. During summer ambient temperatures exceeded the thermoneutral zone of the rock hyrax throughout most of the day, while crevice temperatures remained within the thermoneutral zone of rock hyrax. However, in summer variation in core body temperature was small. Minimum and maximum body temperatures did not coincide with minimum and maximum ambient temperatures. Constant body temperatures were also recorded when ambient temperatures reached lethal limits. During summer it is likely that rock hyrax select cooler refugia to escape lethal temperatures and to prevent excessive water loss. Body temperature of rock hyrax recorded in this study reflects the adaptability of this animal to the wide range of ambient temperatures experienced in its natural environment.

Digestive processes determine whether the particular diet of a bird is utilized efficiently and whether energetic demands are met. Assimilation efficiency is often used as an index of whether a diet is digested optimally. Studies on the digestive processing of generalist feeders are scarce. Cape White-eyes Zosterops pallidus have a diverse diet of fruit, nectar and insects. The nutrient contents of these three diets vary considerably and require quite different digestive processing. This study compared the digestive efficiencies of Cape White-eyes on these three diets by measuring transit times and assimilation efficiency. Cape White-eyes lost body mass significantly when fed fruit, while they maintained and gained body mass on nectar and mealworm diets, respectively. Assimilation efficiency varied significantly between the three diet types (nectar>mealworms>apples). When given a choice of diets, Cape White-eyes selected the diet, which was most efficiently digested and yielded the greatest energetic reward. Diet preference trials further showed that Cape White-eyes regulated daily energy intake. Assimilation efficiency depends on the accessibility of nutritional contents of a diet. Cape White-eyes did not maximize assimilation efficiency. Instead, they adjusted transit time to maximize the rate of energy gain per gram of food in order to maintain energy balance.

Although dopaminergic transmission has been strongly implicated in alcohol self-administration, the involvement of specific dopamine receptor subtypes has not been well established. We studied the ethanol preference and sensitivity of D2-receptor-deficient mice to directly evaluate whether dopamine D2 receptors contribute to alcohol (ethanol) consumption. We report a marked aversion to ethanol in these mice, relative to the high preference and consumption exhibited by wild-type littermates. Sensitivity to ethanol-induced locomotor impairment was also reduced in these mutant mice, although they showed a normal locomotor depressant response to the dopamine D1 antagonist SCH-23390. These data demonstrate that dopamine signaling via D2 receptors is an essential component of the molecular pathway determining ethanol self-administration and sensitivity.

The present experiments examined the effects of different environmental conditions on acute morphine sensitivity and morphine self-administration in two genetically diverse inbred strains of rats. Fischer-344 and Lewis rats were subjects because they are related to the commonly used Sprague-Dawley strain, but differ from each other in behavioral and biological responses to opioids and environmental conditions. It was hypothesized that differential behavioral and biological responses to morphine under the various environmental conditions would be strain dependent. In Experiment 1, behavioral and biological effects of acute morphine injections were examined in 96 Fischer-344 and 96 Lewis rats that were either group housed, individually housed, or group housed and immobilized. F-344 rats were more sensitive to morphine's analgesic and locomotor effects, whereas Lewis rats were more sensitive to morphine's effects on body temperature, vertical movements, and rotarod performance. Strain-dependent environmental effects on the acoustic startle response, vertical activity, speed, and body temperature also were found. Further, environmental conditions interacted with strain of rat to produce differential effects of morphine on hot-plate and speed of locomotion. Specifically, F-344 rats had different responses to morphine under the different environmental conditions, whereas for Lewis rats the responses to morphine did not change on these measures. In addition to behavioral changes, strain-dependent environmental influences on peripheral and central morphine levels also were found. In Experiment 2, the effects of the same environmental conditions on subsequent morphine self-administration were examined in 30 Fischer-344 and 30 Lewis rats. Morphine self- administration of F-344 rats was more affected by the different environmental conditions than was the self-administration behavior of Lewis rats.

The present experiment examined food and water consumption under different housing conditions in 20 female and 20 male Wistar rats. Food and water consumption were measured for 6 h a day following an 18-h same-sex crowded or individual housing period for each of 6 days. All subjects were individually housed during the 6-h measurement period and had access to food and water. Female rats consumed more food and water than did male rats during the 6-h period, regardless of their 18-h housing condition. In addition, previously crowded rats consumed more food and water during the 6-h period than did rats that were previously individually housed. During the 18-h period, when subjects were differentially housed, males consumed more food and water than did females; crowded rats ate less than did individually housed rats; and crowded rats drank more water than did individually housed rats. Based on plasma corticosterone data, the female and male rats were differentially affected by housing conditions. The present results are discussed with regard to housing conditions per se and sex differences in stress responses to housing.