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Accurate correlations between a wide range of physical fitness measures and occupational demands are needed in order to identify specific fitness tests and training needs for firefighters. Twenty professional firefighters performed numerous fitness and job-related performance tests. Pearson product moment correlations were performed to identify the relationship between fitness components and job performance. Significant correlations (p <0.05) with job performance were identified for total fitness (r = -0.62), bench press strength (r = -0.66), hand grip strength (r = -0.71), bent-over row endurance (r = -0.61), bench press endurance (r = -0.73), shoulder press endurance (r = -0.71), bicep endurance (r = -0.69), squat endurance (r = -0.47), and 400-m sprint time (r = 0.79). It is apparent that firefighting taxes virtually all aspects of physical fitness. These data can help the exercise specialist choose appropriate tests and prescribe specific fitness programs for firefighters. Traditional firefighter exercise programs focusing mainly on cardiovascular fitness should be replaced with physical conditioning programs that address all components of fitness.  相似文献   

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Primary veloplasty or primary palatoplasty: some preliminary findings   总被引:2,自引:0,他引:2  
Staged palatal closure was carried out in 30 children. The soft palate was closed at 9 months and the hard palate at 5 years. These patients were followed up for 7 years, and it was found that although the incidence of lateral crossbite was reduced in both unilateral and bilateral cases, the speech results were less satisfactory than those obtained with total palatal closure. In this series, there were two fistulae at the junction of the hard and soft palate. This was related to difficulty in closing this area in some patients at the time of the second operation. As a result, the procedure is not advised. An alternative palatal closure technique is described. This technique consists of nasal layer closure, careful dissection and reconstruction of the levator musculature, transverse division of the nasal layer, insertion of a buccal flap for lengthening, and closure of the oral layer with Veau flaps without dissection behind the tuberosities and with almost total closure of the lateral donor sites on the palatal shelves. In this way there is minimal scarring, particularly in the retrotuberosity area. This is felt to be important since it would seem from studies of facial growth that this is a much more significant area than the palatal shelves.  相似文献   

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When primate societies merge, the probabilities of genetic combinations are altered. What occurs when previously unacquainted groups meet is a product of the social organization of the species and a major contributor to genetic variance. Two colonies ofSaimiri sciureus that had lived independently for five to seven years were permitted to meet. One colony was subjected to injurious aggression by a second colony. We suggest that the demographic characteristics of the groups are suggestive determinants of the acceptance or rejection of unfamiliarSaimiri.  相似文献   

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Circadian performance rhythms: some practical and theoretical implications   总被引:7,自引:0,他引:7  
Safety and productivity are low at night and this would appear to be because we are a diurnal species. This is reflected not only in our habitual sleep time, but also in our endogenous body clocks that, together with exogenous influences, such as the patterning of meals and activity, result in predictable circadian (24 h) rhythms in our physiological processes. Our performance capabilities also vary over the course of our waking period, with task demands affecting both the precise trend over the day, and the rate at which it adjusts to the changes in sleep timing occasioned by shift work. Studies designed to examine the reasons for this have shown that memory loaded performance may have a quite separate endogenous component to that responsible for more simple performance, suggesting that these two types of performance cannot be causally related. Furthermore, it would appear that the exogenous component of circadian rhythms may also differ across measures, and our attempts to model these endogenous and exogenous components have led us to re-examine the evidence on adjustment to night work. Our findings suggest that shiftworkers merely 'stay up late' on the night shift, rather than adjust to it, and that this is responsible for the reduced safety at night. It would seem that in situations where safety is paramount, the only solution to these problems is the creation of a nocturnal sub-society that not only always works at night but also remains on a nocturnal routine on rest days.  相似文献   

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Nevin JA 《Behavioural processes》2012,90(1):84-6; discussion 87-8
In this article, Gallistel proposes information theory as an approach to some enduring problems in the study of operant and classical conditioning.  相似文献   

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Eighty-three cases having a cervical smear result showing abnormal glandular cells were identified and matched up with the diagnostic histology result. Thirty-four (41.0%) were associated with malignancy and 26 (31.3%) with a cervical intraepithelial lesion without invasion. Thirty-eight (45.8%) had conditions of the cervix as follows: 12 cases had invasive disease of the cervix; nine (10.8%) adenocarcinoma of cervix and three (3.6%) squamous carcinoma of cervix. Nineteen (22.9%) had cervical intraepithelial neoplasia (CIN/SIL) alone and seven (8.4%) had cervical glandular intraepithelial neoplasia (CGIN) +/- CIN. There were 16 (19.3%) cases with malignancies of the uterine corpus and six (7.2%) had a malignancy arising from another primary site. Twenty-three (27.7%) had no malignant or pre-malignant condition. The risk of malignancy was related to age and ranged from 18.2% in those under 35 years to 67.9% in those 55 years and over. A protocol for the management of these cases is described.  相似文献   

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Neurons are faced with the formidable challenge of having to assemble most of their cytoskeleton at axonal sites far removed from the protein synthetic machinery in the perikaryon. Their achievement seems all the more impressive now that new evidence is showing that the cytoskeleton may vary markedly in size and composition along the axon and exhibit striking regional specializations. Further complexity is contributed to this structure by a growing assortment of cytoskeleton-associated proteins that cross-link the various fibrous elements and stabilize cytoskeletal architecture. Much of the dynamic behavior of cytoskeletal proteins and polymers in axons is locally controlled. This regulation involves, in part, a system of protein kinases and phosphatases modulated by both intercellular and intracellular signals. Conceptual models of slow axonal transport have evolved to accommodate these new findings. BioEssays 20 :798–807, 1998. © 1998 John Wiley & Sons, Inc.  相似文献   

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Differences in the cardiovascular responses of individuals with behavior patterns of Type A and Type B were investigated during rest, stress, and recovery by visual stimulation. Thirty healthy undergraduate and graduate students (mean age: 22.18+/-1.44 years) were categorized as Type A (N=14), or Type B (N=16) based on the Kwansei Gakuin's daily life questionnaire. The cardiovascular reactivity of all participants was repetitively monitored for 6 sessions, with each session comprising 3 conditional phases, viz., resting, stress, and post-stress recovery. A gray screen was displayed during resting, displeasure-evoking images were displayed under the stress condition, and video clips of a forest or a control image (a gray screen) were displayed during the recovery condition. When participants were subjected to different stimuli on a 42-inch plasma television screen in each session, electrocardiograms (ECG), impedance cardiograms and the blood pressure (BP) of the respective participants were continuously monitored. According to the results, Type A indicated higher sympathetic reactivity than Type B during resting and under stress. As such, Type A indicated a shorter pre-ejection period (PEP) level during resting and a greater cardiac output (CO) increase under stress than Type B. Furthermore, parasympathetic predominance and parasympathetic antagonism accompanying the enhanced sympathetic activity induced by the unpleasant stress images decreased heart rate (HR) in both Type A and Type B, although the decrease in Type A was relatively meager. Unlike previous studies, the present study demonstrated that Type A indicated more enhanced sympathetic reactivity than Type B in resting physiological arousal levels and visual stimulus-induced stress.  相似文献   

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Background

In recent years, the physiological relaxation effects of natural environments have been widely exploited, and although individual differences in the effects of forest therapy are known, assessment methods have not been clearly established. This study used a classification based on Type A and Type B behavior patterns to explain individual differences in physiological responses to forest environments.

Methods

We performed physiological experiments in 44 forest and urban (controls) areas. In total, 485 male university students (age, 21.8 ± 1.6 years) participated in the study. The subjects were asked to visit forest or urban environments randomly and observe each landscape for 15 min. The subjects’ pulse rates and blood pressures were tested to evaluate their physiological responses. The Kwansei Gakuin daily life questionnaire was used to identify Type A and Type B behavior patterns in subjects.

Results

The pulse rate was significantly lower in the Type B group after exposure to forest areas than after exposure to urban areas, whereas no significant difference was observed in the Type A group. In addition, the pulse rate was significantly lower in the low scoring subjects in the Type B group, which was consistent with changes in their diastolic blood pressure.

Conclusions

These results suggest that individual differences in pulse rate and blood pressure in response to forest environments can be explained by Type A and Type B behavior patterns.  相似文献   

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Nurses' empathy for and connection with patients demonstrates core professional values which are essential but, consequently, attract certain factors capable of inducing stress. Studies of the roles and responsibilities associated with nursing have implicated multiple and conflicting demands which might not be without some resultant effects. However, little research has been conducted on these work characteristics in developing economies to determine how these might impact the nurse employees' performance. There is need for evidence-based empirical findings to facilitate improvement in healthcare services. This study examined stress and level of burnout among Nigerian nurses (n = 2245) who were selected using stratified random sampling. The participants were measured using an 'abridged measures booklet' adopted from the Maslach Burnout Inventory-General Survey (MBI-GS), Job Autonomy Questionnaire (JAQ), Questionnaire on Organisational Stress-Doetinchem (VOS-D) and Job Diagnostic Survey (JDS). The roles of work-home interference (WHI) and home-work interference (HWI), with respect to work characteristics and burnout (paying special attention to gender), were examined. Analyses using t-tests and linear regression showed no gender differences in burnout levels among Nigerian nurses, who experience medium to high levels of emotional exhaustion, medium levels of depersonalisation and high levels of personal accomplishment. WHI and HWI were found to mediate the relationship between work characteristics and burnout. The meditational relationship differs between genders. This study calls for further research into gender and burnout among the caring professions, especially in under-developed and developing economies of the world.  相似文献   

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