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71.
The mother-infant bond in bottlenose dolphins is critical to infant survival and has been reported to last from 3-10 years in both captive and wild populations. Little information on mother-infant communication during early development has been collected. This paper reports on a newly discovered dolphin vocalization, termed thunk, which is predominantly used by mothers toward infants. Four mother-infant pairs and one aunt-infant pair were the subjects for this study. Methods included a focal animal sampling technique using 2.5 min interval and event/continuous sampling regimes on audio- or videotape. Results indicated that thunks are produced by mothers or aunting females during infant departures (distances greater than 5 feet) and are frequently followed by disciplinary activity by the mother or aunt. In addition, thunks appeared to cease at approximately 9-10 months after birth, concurrent with a decrease in infant dependence. Thunks also were analyzed acoustically for frequency and duration parameters. Thunks have a harmonic structure with an energy peak in the 273–350 Hz range and ranged from 129–5,556 Hz in frequency and from 21–171 ms in duration. They appear to function as aggressive contact vocalizations produced by mothers and other adult females toward infants in order to maintain infant proximity. © 1995 Wiley-Liss, Inc.  相似文献   
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Laboratory and zoo housed non-human primates sometimes exhibit abnormal behaviors that are thought to reflect reduced wellbeing. Previous research attempted to identify risk factors to aid in the prevention and treatment of these behaviors, and focused on demographic (e.g. sex or age) and experience-related (e.g. single housing or nursery rearing) factors. However, not all animals that display abnormal behavior possess these risk factors and some individuals that possess a risk factor do not show behavioral abnormalities. We hypothesized that other aspects of early experience and individual characteristics might identify animals that were more likely to display one specific abnormal behavior, motor stereotypy (MS). Using logistic regression we explored the influence of early rearing (involving four different types of rearing conditions), and variation in temperament, on likelihood of displaying MS while controlling for previously identified risk factors. Analyses indicated that having a greater proportion of life lived indoors, a greater proportion of life-indoors singly-housed, and a greater number of anesthesias and blood draws significantly increased the risk of displaying MS (P < 0.001). Rearing condition failed to independently predict the display of MS; however significant interactions indicated that single housing had a greater impact on risk for indoor-reared animals versus outdoor-reared animals, and for indoor mother-reared animals versus nursery-reared animals. There were no main effects of temperament, although interactions with rearing were evident: scoring high on Gentle or Nervous was a risk factor for indoor-reared animals but not outdoor-reared animals. The final model accounted for approximately 69.3 % of the variance in the display of MS, and correctly classified 90.6% of animals. These results indicate that previously identified risk factors may impact animals differently depending on the individual's early rearing condition. These results are also the first in non-human primates to demonstrate that individual difference factors, like temperament, could be additional tools to identify animals at highest risk for motor stereotypy.  相似文献   
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Background  

Addressing the problem of preventable drug related morbidity (PDRM) in primary care is a challenge for health care systems internationally. The increasing implementation of clinical information systems in the UK and internationally provide new opportunities to systematically identify patients at risk of PDRM for targeted medication review. The objectives of this study were (1) to develop a set of explicit medication assessment criteria to identify patients with sub-optimally effective or high-risk medication use from electronic medical records and (2) to identify medication use topics that are perceived by UK primary care clinicians to be priorities for quality and safety improvement initiatives.  相似文献   
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In this study we sought to determine whether dog barks could be divided into subtypes based on context. We recorded barking from 10 adult dogs, Canis familiaris, of six breeds in three different test situations: (1) a disturbance situation in which a stranger rang the doorbell, (2) an isolation situation in which the dog was locked outside or in a room isolated from its owner and (3) a play situation in which either two dogs or a human and a dog played together. We analysed spectrograms of 4672 barks using macros that took 60 sequential frequency measurements and 60 sequential amplitude measurements along the length of the call. Statistical analyses revealed that barks are graded vocalizations that range from harsh, low-frequency, unmodulated calls to harmonically rich, higher-frequency, modulated calls. The harsh, low-frequency, unmodulated barks were more commonly given in the disturbance situation, and the more tonal, higher-pitch, modulated barks were more commonly given in the isolation and play situations. Disturbance barks were also longer in duration with more rapid repetition than the barks given in other contexts. Discriminant analysis revealed that dog barks can be divided into different subtypes based on context even within individual dogs, and that dogs can be identified by their bark spectrograms despite the context of the bark.  相似文献   
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