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1.
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Diversity patterns cannot be properly interpreted without a theory providing criteria for their evaluation. We propose a concept to prevent artifictions caused by improper consideration of changes in observed patterns due to variation in taxon delimitation. Most biodiversity patterns concern assemblages of species of given higher taxon (e.g. class). Some patterns seem to be universal, e.g., body size distribution, species-abundance distribution, species-area relationship, or the relationship between diversity and energy availability. However, truly universal patterns should not change when we change taxonomic scope by focusing on subtaxa or when we merge several sister taxa together and analyze patterns in resulting higher taxon. Similarly, some patterns may not change when changing the basic unit of the study e.g., when replacing species by genera or families (or any monophyletic clades), although other patterns may not be invariant against the variation of the basic unit. In fact, there are only two possibilities: biodiversity patterns are either taxon-invariant or they vary systematically with taxonomic resolution, which would indicate some fundamental taxonomic level with interesting implications for biological processes behind those patterns. Here we develop the concept of taxon invariance of diversity patterns and apply it on the abovementioned patterns. We show that simple theoretical considerations markedly constrain the set of possible patterns, as some of them cannot be simultaneously valid for both a taxon and its subtaxa – frequency distributions of abundances cannot be simultaneously lognormal for a given taxon and all its subtaxa, the taxa-area relationship cannot follow a power-law for all levels of taxonomic resolution, and energy availability cannot affect diversity of all taxonomic units in the same way. Analyses of the variation in the form of biodiversity patterns with changing taxonomic resolution thus provide an extremely useful tool for revealing properties of respective patterns, their universality and logical consistency.  相似文献   

3.
《Anthrozo?s》2013,26(1):29-37
ABSTRACT

Phobic fear can be regarded as an emotional response syndrome consisting of three groups of response patterns, namely cognitive-affective, motor-behavioral and physiological. In the present study, female students were assigned to two groups: an experimental group consisting of participants suffering from dog phobia, and a control group. The study consisted of three stages: the resting stage measured baseline values, while the pre- and post-intervention stages measured values in the presence of a dog stimulus. Cognitive-affective aspects were assessed by an anxiety scale and post-study questionnaire. Motor-behavioral aspects focussed on dog approach termination distances and the observation of non-verbal communication cues during behavioral approach tests. Physiological aspects were measured in terms of plasma adrenocorticotropic hormone (ACTH) levels. Systematic desensitization therapy was found to be effective in alleviating motor-behavioral and cognitive-affective aspects, while its effect on plasma ACTH levels was inconclusive. No significant plasma ACTH level changes occurred in the experimental group during the study. When comparing the experimental and control groups, the only significant difference was a lower plasma ACTH level in the control group during the post-intervention stage. Total stressor schedule values suggest that participants in the experimental group had a predisposition to be generally more anxious and fearful than participants in the control group.  相似文献   

4.
The temporal organization of behavioral patterns and metabolic activity was assessed in chronic low protein malnourished rats and their nutritional controls at 60 days of age. Spontaneous activity was video-recorded during 3 days for 10 min every hour and the frequency of exploration, grooming and ingestive behaviors was obtained, their basal metabolic rate was measured during 5 min every hour for one 24 h cycle. Rats of both nutritional groups showed a clear diurnal rhythmicity in all behavioral patterns, characterized by an increase of activity during the dark phase and a decrease during the light phase. Effects of malnutrition were selective and produced mainly a general decrease of the mean value and amplitude of the rhythm of ingestive behavior, as well as a bimodal pattern and rhythmic components of 12, 24 and 30 h according to autocorrelation and cosinor analysis. In both groups, the metabolic rate showed a bimodal diurnal rhythm, which fitted significantly to a 12 h period model and was not affected in malnourished rats. These data provide evidence that the circadian system is highly resistant to malnutrition. In malnourished rats rhythmicity of ingestive behavior was specifically affected, probably because the relation between metabolic processes and ingestive behaviors may be enhanced as a compensatory mechanism aimed to counteract the deficient diet composition.  相似文献   

5.
The temporal organization of behavioral patterns and metabolic activity was assessed in chronic low protein malnourished rats and their nutritional controls at 60 days of age. Spontaneous activity was video-recorded during 3 days for 10 min every hour and the frequency of exploration, grooming and ingestive behaviors was obtained, their basal metabolic rate was measured during 5 min every hour for one 24 h cycle. Rats of both nutritional groups showed a clear diurnal rhythmicity in all behavioral patterns, characterized by an increase of activity during the dark phase and a decrease during the light phase. Effects of malnutrition were selective and produced mainly a general decrease of the mean value and amplitude of the rhythm of ingestive behavior, as well as a bimodal pattern and rhythmic components of 12, 24 and 30 h according to autocorrelation and cosinor analysis. In both groups, the metabolic rate showed a bimodal diurnal rhythm, which fitted significantly to a 12 h period model and was not affected in malnourished rats. These data provide evidence that the circadian system is highly resistant to malnutrition. In malnourished rats rhythmicity of ingestive behavior was specifically affected, probably because the relation between metabolic processes and ingestive behaviors may be enhanced as a compensatory mechanism aimed to counteract the deficient diet composition.  相似文献   

6.

Objectives

To test the inter-rater reliability of the RoB tool applied to Physical Therapy (PT) trials by comparing ratings from Cochrane review authors with those of blinded external reviewers.

Methods

Randomized controlled trials (RCTs) in PT were identified by searching the Cochrane Database of Systematic Reviews for meta-analysis of PT interventions. RoB assessments were conducted independently by 2 reviewers blinded to the RoB ratings reported in the Cochrane reviews. Data on RoB assessments from Cochrane reviews and other characteristics of reviews and trials were extracted. Consensus assessments between the two reviewers were then compared with the RoB ratings from the Cochrane reviews. Agreement between Cochrane and blinded external reviewers was assessed using weighted kappa (κ).

Results

In total, 109 trials included in 17 Cochrane reviews were assessed. Inter-rater reliability on the overall RoB assessment between Cochrane review authors and blinded external reviewers was poor (κ  =  0.02, 95%CI: −0.06, 0.06]). Inter-rater reliability on individual domains of the RoB tool was poor (median κ  = 0.19), ranging from κ  =  −0.04 (“Other bias”) to κ  =  0.62 (“Sequence generation”). There was also no agreement (κ  =  −0.29, 95%CI: −0.81, 0.35]) in the overall RoB assessment at the meta-analysis level.

Conclusions

Risk of bias assessments of RCTs using the RoB tool are not consistent across different research groups. Poor agreement was not only demonstrated at the trial level but also at the meta-analysis level. Results have implications for decision making since different recommendations can be reached depending on the group analyzing the evidence. Improved guidelines to consistently apply the RoB tool and revisions to the tool for different health areas are needed.  相似文献   

7.
Diurnal patterns of spore release have been observed in a number of fungal pathogens that undergo wind-assisted dispersal. The mechanisms that drive these patterns, while not well understood, are thought to relate to the ability of dispersing spores to survive their journey and infect new hosts. In this paper, we characterise the diurnal pattern of ascospore release by a Western Australian population of Leptosphaeria maculans. Although L. maculans has been previously shown to exhibit diurnal patterns of ascospore release, these patterns appear to vary from region to region. In order to characterise the pattern of release in the Mediterranean climate of Western Australia, we analysed historical data describing the bi-hourly count of airborne ascospores at Mt Barker, Western Australia. Results of this analysis showed diurnal patterns that differ from those previously observed in other countries, with ascospore release in our study most likely to occur in the afternoon. Furthermore, we found that the time of peak release can shift from month to month within any one season, and from year to year. In explaining the hourly pattern of spore release over an entire season, time since rainfall, time since last release, temperature, hour and month were all shown to be significant variables.  相似文献   

8.
啄木鸟科物种作为初级洞巢者与蛀干害虫控制者,对森林高度依赖,是森林生态系统重要的伞护种和环境指示物种。自20世纪以来,由于全球范围的栖息地丧失和片段化,啄木鸟科物种的森林生境急剧萎缩,威胁着该类群物种的生存和繁衍。为探究啄木鸟科动物濒危情况和研究现状,本研究利用世界自然保护联盟濒危物种红色名录(IUCN Red List)和国际鸟盟(BirdLife International)在线数据库,检索并整理出1988年到2023年以下内容:(1)全球啄木鸟的物种数、濒危等级及其变化情况;(2)各大洲的啄木鸟物种数及其受威胁物种的比例;(3)啄木鸟的主要威胁因素;(4)通过Google学术搜索等方式检索并统计啄木鸟相关文章的研究内容。结果显示:(1)目前现存254种啄木鸟,33年间全球受威胁啄木鸟由7种增加至18种,受威胁物种数占当年已命名啄木鸟物种数的比例由3.4%上升至7.0%。(2)亚洲、南美洲和北美洲各分布了83种、93种和56种啄木鸟,受威胁物种占比分别为12.0%、6.4%、5.3%。非洲和欧洲分别分布了36种和11种啄木鸟,当前没有受威胁物种。(3)农业和生物资源利用以及放牧是啄木鸟的主要威胁因素。(4)共检索到研究啄木鸟的有关文章1 024篇,研究覆盖了140种啄木鸟,其中,文章数最多的物种是红顶啄木鸟(Leuconotopicus borealis)(162篇)。研究主要集中在巢相关特征(129篇)、生境选择特征(122篇)、取食行为(112篇)、繁殖行为(99篇)和种群状况(66篇)等基础生态学内容。这些研究为啄木鸟生物学、生态学积累了一定的基础,但物种覆盖程度还远远不够。在生物多样性急剧丧失的大背景下,亟需开展更为广泛和深入的研究。本研究对全球啄木鸟的濒危格局与研究现状进行了全面的分析,以期为后续啄木鸟的研究与保护工作提供参考。  相似文献   

9.
An animal's ability to avoid predation likely depends on its ability to detect approaching predators, conceal itself, and seek refuge or protection from predators. Habitat, especially vegetation structure, can influence all of these factors concurrently. Binary categorical assessments of habitat as ‘open’ or ‘closed’, however, confound at least two functions of habitat structure that could influence the perceived risk of predation: concealment, which functions to hide an individual, and visibility, which enhances detection of a potential predator. Both can influence predation risk independently and s imultaneously. In this study, we decoupled these functional properties of vegetation and studied the effects of concealment, visibility, and proximity to a refuge on the distance at which pygmy rabbits (Brachylagus idahoensis) fled from an approaching threat (flight initiation distance; FID). Concealment by vegetation decreased perceptions of risk; however, pygmy rabbits exhibited elevated risk at high levels of visibility, regardless of the amount of concealment. Proximity to burrow entrances also influenced perceptions of risk, such that risk was significantly lower when rabbits were on or near burrow systems. Disentangling the functional properties of habitat can provide a more comprehensive understanding of the factors that influence perceived risk and escape behaviors of prey and provide insight into how habitat structure mechanistically relates to predation risk.  相似文献   

10.
Factors affecting or inducing nightmares have been investigated repeatedly. However, little research is carried out on the behavioral consequences of nightmares. The present study thus served to investigate behavioral effects of nightmares in correlation to personality variables. 41 non-clinical participants, who suffer from about 2 nightmares per month recorded their dreams and nightmares over a 4-week period. A nightmare was defined as a dream that frightens the dreamer and could be recalled in detail on awakening. Anxiety and mood were monitored every morning. All nightmares and their behavioral consequences were noted on a questionnaire. Personality traits and life events were assessed at the beginning of the investigation. 100 nightmares were reported by the subjects over the 4-week period (range: 0–8). Following a nightmare, the subjects were significantly more anxious and were of a less stable mental condition compared to nights without nightmares. Additionally, nightmares induced physical complaints. This was considered to be an indicator that something was wrong in their lives and induced them to solve personal problems. The behavioral effects were most pronounced in subjects scoring high on neuroticism and on the number of physical complaints and low on achievement orientation and openness. The results suggest that sufferers of nightmares intend to change their lives, especially those with a neurotic-like personality.  相似文献   

11.
With aging, incidence of severe stress-related diseases increases. However, mechanisms, underlying individual vulnerability to stress and age-related diseases are not clear. The goal of this review is to analyze finding from the recent literature on age-related characteristics of the hypothalamic-pituitary-adrenal (HPA) axis associated with stress reactivity in animals that show behavioral signs of anxiety and depression under mild stress, and in human patients with anxiety disorders and depression with emphasis on the impact of the circadian rhythm and the negative feedback mechanisms involved in the stress response. One can conclude that HPA axis reaction to psycho-emotional stress, at least acute stress, increases in the aged individuals with anxiety and depression behavior. Elevated stress reactivity is associated with disruption of the circadian rhythm and the mineralocorticoid receptor-mediated glucocorticoid negative feedback. The disordered function of the HPA axis in individuals with anxiety and depression behavior can contribute to aging-related pathology.  相似文献   

12.
Male cricket frogs ( Acris crepitans ) gather in breeding choruses and call to attract females. The call also serves to maintain an individual's calling space. When an intruder invades a resident male's space, the resident will display one of three behavior patterns. He will either attack the intruder, abandon calling, or tolerate the intruder's presence and continue calling. We simulated an intruder by broadcasting a stimulus from a speaker and categorized the response of the resident male. We recorded social variables relevant to local competition among males, specifically, local caller density (within 2 m) and the amplitude of the nearest neighbor's calls. In addition we recorded the size of the subject, the amplitude of the stimulus, and the time of night and the season. We used a multivariate approach to assess the relative importance of these variables. Local caller density and nearest neighbor call amplitude were the best predictors of a resident's response to the intruder; higher levels of local competition resulted in more males tolerating the intruder. In addition, behavior changed over the season: males were more likely to abandon or ignore the intruder early in the season and more likely to attack later in the season. No other variables were related to the outcome of the agonistic encounter. This study suggests that the most important variables impinging on a male's decision to fight, flee, or ignore an intruder are influences external to the individuals involved in the conflict.  相似文献   

13.
《Plains anthropologist》2013,58(21):182-188
Abstract

Several hypotheses of behavioral adaption in economic contexts of a variable habitat are put forth and examined in terms of the decisions and ethos concerning the risks and modes of rationality necessary for successful adaption.  相似文献   

14.
In this study, we examine the effect of Tarangire National Park (TNP) on local perceptions of risk and how these perceptions may influence behavioral responses. Data were collected during 2004–2005 through household surveys and participatory risk mapping (PRM) in eight villages east of TNP. By identifying and rank-ordering respondents’ perceived risks, PRM enhances understanding of the nature and variation of risks faced within a population by distinguishing between the incidence and severity of subjective risk perceptions. Results indicate that proximity to the park has a strong effect on the type and severity of perceived risks. Within villages close to the park, however, behavioral response to perceived risks varies considerably. This study contributes to an appreciation of how behavioral response to environmental and socioeconomic factors is mediated by human perception.
Timothy D. BairdEmail:
  相似文献   

15.
16.

Background

Anxiety and depression in children and adolescents are undertreated. Computer- and Internet-based cognitive behavioral treatments (cCBT) may be an attractive treatment alternative to regular face-to-face treatment.This meta-analysis aims to evaluate whether cCBT is effective for treating symptoms of anxiety and depression in youth.

Methods and Findings

We conducted systematic searches in bibliographical databases (Pubmed, Cochrane controlled trial register, PsychInfo) up to December 4, 2013. Only randomized controlled trials in which a computer-, Internet- or mobile-based cognitive behavioral intervention targeting either depression, anxiety or both in children or adolescents up to the age of 25 were compared to a control condition were selected. We employed a random-effects pooling model in overall effect analyses and a mixed effect model for sub-group analyses. Searches resulted in identifying 13 randomized trials, including 796 children and adolescents that met inclusion criteria. Seven studies were directed at treating anxiety, four studies at depression, and two were of a transdiagnostic nature, targeting both anxiety and depression. The overall mean effect size (Hedges’ g) of cCBT on symptoms of anxiety or depression at post-test was g=0.72 (95% CI:0.55-0.90, numbers needed to be treated (NNT)=2.56). Heterogeneity was low (I²=20.14%, 95% CI: 0-58%). The superiority of cCBT over controls was evident for interventions targeting anxiety (g=0.68; 95% CI: 0.45-0.92; p < .001; NNT=2.70) and for interventions targeting depression (g=0.76; 95% CI: 0.41-0.12; p < .001; NNT=2.44) as well as for transdiagnostic interventions (g=0.94; 95% CI: 0.23-2.66; p < .001; NNT=2.60).

Conclusions

Results provide evidence for the efficacy of cCBT in the treatment of anxiety and depressive symptoms in youth. Hence, such interventions may be a promising treatment alternative when evidence based face-to-face treatment is not feasible. Future studies should examine long-term effects of treatments and should focus on obtaining patient-level data from existing studies, to perform an individual patient data meta-analysis.  相似文献   

17.
One hundred and seventy-two strains of Escherichia coli isolated from diarrheal patients in Beijing, P. R. China, were analyzed for plasmid DNA profile, HEp-2 cell adherence ability and reactivity to 10 previously described DNA probes. They had not been recognized as pathogenic E. coli in China. Of the 110 strains tested, 76 (69%) contained one or multiple large plasmids. Of the 71 strains with the large plasmids 64 could adhere to HEp-2 cells. Of the 172 strains, 102 (59.3%) were hybridized with at least one of the 10 probes. Of those, seven strains hybridized with enteroaggregative E. coli (EAggEC) probe. Their serotypes were O128 (two strains), O6 (one strain), and O111 (one strain). Three strains were untypable. Six and three strains were hybridized with enteropathogenic E. coli (EPEC) attaching and effacing genes (eae) or EPEC adherence factor (EAF) probe, respectively. Two non-O157: H7 strains hybridized with enterohemorrhagic E. coli (EHEC) probe. Seventy-two strains (41.9%) hybridized with shiga-like toxin 2 or 1 (SLT2 or SLT1) probes. Among the SLT1 or SLT2 probe-positive strains, 54 hybridized with invasive (INV) plasmid probe developed for identification of enteroinvasive E. coli (EIEC) and Shigella species. The INV and SLT probe-positive strains might represent a new variety of verotoxin-producing E. coli (VTEC).  相似文献   

18.

Background

In 2008, the Portuguese smoke-free law came into effect including partial bans in the leisure-hospitality (LH) sector. The objective of the study is to assess the prevalence of smoking control policies (total ban, smoking permission and designated smoking areas) adopted by the LH sector in Portugal. The levels of noncompliance with each policy are investigated as well as the main factors associated with smoking permission and noncompliance with the law.

Methods

Cross-sectional study conducted between January 2010 and May 2011. A random sample of venues was selected from the Portuguese LH sector database, proportionally stratified according to type, size and geographical area. All venues were assessed in loco by an observer. The independent effects of venues'' characteristics on smoking permission and the level of noncompliance with the law were explored using logistic regression.

Results

Overall, 1.412 venues were included. Total ban policy was adopted by 75.9% of venues, while 8.4% had designated smoking areas. Smoking ban was more prevalent in restaurants (85.9%). Only 29.7% of discos/bars/pubs opted for complete ban. Full or partial smoking permission was higher in discos/bar/pubs (OR = 7.37; 95%CI 4.87 to 11.17). Noncompliance with the law was higher in venues allowing smoking and lower in places with complete ban (33.6% and 7.6% respectively, p<0.001). Discos/bars/pubs with full smoking permission had the highest level of noncompliance (OR = 3.31; 95%CI 1.40 to 7.83).

Conclusions

Our findings show a high adherence to smoking ban policy by the Portuguese LH sector. Nonetheless, one quarter of the venues is fully or partially permissive towards smoking, with the discos/bars/pubs considerably contributing to this situation. Venues with smoking permission policies were less compliant with the legislation. The implementation of a comprehensive smoke-free law, without any exceptions, is essential to effectively protect people from the second hand smoke.  相似文献   

19.

Objective(s)

Edoxaban, a factor Xa inhibitor, is a new oral anticoagulant that has been developed as an alternative to vitamin K antagonists. However, its safety remains unexplored.

Methods

Medline, Embase and Web of Science were searched to March 8, 2014 for prospective, randomized controlled trials (RCTs) that assessed the safety profile of edoxaban with warfarin. Safety outcomes examined included bleeding risk and mortality.

Results

Five trials including 31,262 patients that met the inclusion criteria were pooled. Overall, edoxaban was associated with a significant decrease in major or clinically relevant nonmajor bleeding events [risk ratio (RR) 0.78, 95% confidence interval (CI) 0.74 to 0.82, p<0.001] and any bleeding events [RR 0.82, 95% CI 0.79 to 0.85, p<0.001]. Edoxaban also showed superiority to warfarin both in all-cause mortality [RR 0.92, 95% CI0.85 to0.99, p = 0.02] and cardiovascular mortality [RR 0.87, 95% CI0.79 to 0.96, p = 0.004]. Subgroup analyses indicated that RRs of edoxaban 30, 60 or 120 mg/d were 0.67 (p<0.001), 0.87 (p<0.001) and 3.3 (p = 0.004) respectively in major or clinically relevant nonmajor bleeding; 0.71 (p<0.001), 0.89 (p<0.001) and 2.29 (p = 0.002) respectively in any bleeding; as well as 0.86 (p = 0.01), 0.87 (p = 0.01) and 0.28 (p = 0.41) respectively in cardiovascular death… Meanwhile, paramount to note that pooled results other than the largest trial showed edoxaban was still associated with a decrease in the rate of major or clinically relevant nonmajor bleeding event (p = 0.02) and any bleeding (p = 0.002), but neither in all-cause death (p = 0.66) nor cardiovascular death (p = 0.70).

Conclusions

Edoxaban, a novel orally available direct factor Xa inhibitor, seems to have a favorable safety profiles with respect to bleeding risk and non-inferior in mortality when compared to warfarin. Further prospective RCTs are urgently needed to confirm the results of this meta-analysis.  相似文献   

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