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341.
We investigated locomotor and postural behavior during terminal branch feeding in order to gain a better understanding of the motor capabilities of primates. We videotaped wild, juvenile bonnet macaques (Macaca radiata) in India as they fed on flower nectar in a simal tree (Bombax malabaricum). Kinematic analysis revealed that they select specific support surfaces and movements that, for their body design and postures, maximize lateral stability and minimize the chances of falling. These choices are made even though the distance and duration of travel to a selected target are frequently increased. Our discussion focuses on particular concepts of how primates contend with balance problems arboreally, potential reasons for changes in footfall patterns, and how the tail contributes to arboreal locomotion and posture. We concluded that balance problems due to the ratio of body size to branch size are usually avoided, at least among juvenile bonnet macaques, by placing the hands and feet on branches extending laterally from the central support branch and not on the central branch itself. The lateral branches permit a wide base of support, which increases lateral stability. Second, juvenile bonnet macaques have a striking ability to rapidly and repeatedly adapt their gait patterns to changing substrate design with minimal interruption to overall progression. Third, primate tails that are not morphologically specialized for prehension nevertheless have important prehensile and sensory functions in arboreal locomotion and posture. 相似文献
342.
Riccardo Dalle Grave Simona Calugi Flavia Magri Massimo Cuzzolaro Elisabetta Dall'Aglio Lucio Lucchin Nazario Melchionda Giulio Marchesini 《Obesity (Silver Spring, Md.)》2004,12(12):2005-2012
Objective: To investigate weight loss expectations (expected 1‐year BMI loss, dream BMI, and maximum acceptable BMI) in obese patients seeking treatment and to examine whether expectations differ by sex, weight, diet and weight history, age, psychological factors, and primary motivations for weight loss. Research Methods and Procedures: 1891 obese patients seeking treatment in 25 Italian medical centers (1473 women; age, 44.7 ± 11.0 years; BMI, 38.2 ± 6.5 kg/m2) were evaluated. Diet and weight history, weight loss expectations, and primary motivation for seeking treatment (health or improving appearance) were systematically recorded. Psychiatric distress, binge eating, and body image dissatisfaction were tested by self‐administered questionnaires (Symptom CheckList‐90, Binge Eating Scale, and Body Uneasiness Test). Results: In 1011 cases (53.4%), 1‐year expected BMI loss was ≥9 kg/m2, dream BMI was 26.0 ± 3.4 kg/m2 (corresponding to a 32% loss), and maximum acceptable BMI was 29.3 ± 4.4 kg/m2 (?23%). BMI and age were the strongest predictors of weight goals. Weight loss necessary to reach the desired targets was largely in excess of weight loss observed during previous dieting. Psychiatric distress, body dissatisfaction, and binge eating did not predict weight loss expectations. The primary motivation for weight loss was concern for future or present health; women seeking treatment to improve appearance had a lower grade of obesity, were younger, and had first attempted weight loss at a younger age. Discussion: Obese Italian patients had unrealistic weight loss expectations. There were significant disparities between patients’ perceptions and physicians’ weight loss recommendations of desirable treatment outcome. 相似文献
343.
A laboratory method is presented for studying zooplankton swimming behaviors such as phototaxis and photokinesis. The method attempts to standardize laboratory conditions and to minimize the effects of several phenomena which modify zooplankton behavior. The role of angular light distribution in zooplankton behavior is discussed, and an apparatus which simulates a natural underwater light environment is described. The procedure minimizes the fluctuations in zooplankton swimming speed and vertical distribution that are caused by large light stimuli, noise, food deprivation, endogenous rhythms, and other factors. The experimental animals were viewed remotely with the aid of a light amplifier and video camera. A mathematical equation and computer program for calculating three-dimensional swimming speeds of zooplankton from video recordings are described in detail. 相似文献
344.
This study aimed to identify treatment, therapist and patient factors associated with dropping out of treatment in four outpatient mental health services. The experimental group comprised all 789 individuals who attended for the first time the mental health services during one year and dropped out of treatment in the same year or during the two following ones. The control group consisted of the same number of individuals, chosen at random from patients who, in the same year, attended for the first time the services and did not subsequently drop out of treatment. The overall drop-out rate was 33.2%. According to logistic regression analysis, the predictive factors of dropping out were: being treated in a particular centre, the involvement of more than one therapist in treatment, having no previous history of psychiatric disorders, being young and being male. 相似文献
345.
Site-specific deamination of five adenosine residues in the pre-mRNA of the serotonin 2C receptor, 5HT2CR, alters the amino acid sequence of the encoded protein. Such RNA editing can produce 32 mRNA variants, encoding 24 protein isoforms that vary in biochemical and pharmacological properties. Because serotonin functions in the regulation of mood and behaviour, modulation of serotonin signalling by RNA editing may be relevant to such psychiatric disorders as anxiety and depression. Several recent human studies have reported changes in 5HT2CR editing in schizophrenia, major depression or suicide, but results are variable and not conclusive. Rodent studies have begun to examine effects of drug treatments and stress. Understanding the importance of 5HT2CR editing in mood and behaviour will be assisted by experiments designed to analyse multiple strains of mice, in different behavioural tests, with optimal evaluation of the time course of molecular changes. 相似文献
346.
RENATO D. ALARCÓN 《World psychiatry》2009,8(3):131-139
This paper aims to provide conceptual justifications for the inclusion of culture and cultural factors in psychiatric diagnosis, and logistic suggestions as to the content and use of this approach. A discussion of the scope and limitations of current diagnostic practice, criticisms from different quarters, and the role and relevance of culture in the diagnostic encounter, precede the examination of advantages and disadvantages of the approach. The cultural content of psychiatric diagnosis should include the main, well-recognized cultural variables, adequate family data, explanatory models, and strengths and weaknesses of every individual patient. The practical aspects include the acceptance of “cultural discordances” as a component of an updated definition of mental disorder, and the use of a refurbished cultural formulation. Clinical “telescoping” strategies to obtain relevant cultural data during the diagnostic interview, and areas of future research (including field trials on the cultural formulation and on “culture bound syndromes”), are outlined. 相似文献
347.
Donald C. McNaught 《Journal of Aquatic Ecosystem Stress and Recovery (Formerly Journal of Aquatic Ecosystem Health)》1992,1(4):271-281
Both acute (ingestion, respiration) and chronic bioassays (reproduction, survival) have been used to identify sources of pollutants. A mass-balance analysis suggests that acute tests be paired, using important indicator species asDaphnia, Ceriodaphnia and potentially others, to estimate the impact of contaminants upon the zooplankton community. Eventually groups of community bioassays may be combined to approximate an ecosystem bioassay. Hormesis or the stimulation of a physiological process by a compound which is toxic at high concentrations is characteristic of several bioassays; in this paper the ecotoxicology community is challenged to keep detailed records of the species, toxic compound, and physiological response involving hormesis in order to understand it; and ultimately to use it to simplify interpretation of bioassays. Life history characteristics of the cladoceran zooplankton, including early reproduction, high net reproductive rates, and the potential for many parthenogenetic generations with constant genotypes and low mutation rates make good choices for environmental bioassays. In contrast, high mutation rates of rotifers make them questionable choices. Five innovations, one or more of which may improve our ability to detect and identify pollutants, are suggested for ecotoxicologists using zooplankton. These include (a) the use of strains of known genotype; (b) determination of the genetic adaptation of clones to common toxins; (c) the use of common behaviors, including responses to light in detection of non-lethal chemicals at ambient levels; (d) record keeping on occurrence of cladoceran tumors; and (e) the determination of precise toxins responsible for the inhibition of zooplankton function and behavior. 相似文献