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1.
Reproductive behaviors of the largemouth triplefin Ucla xenogrammus were observed on reefs of Kuchierabu-jima Island, southern Japan. Males exclusively maintained home ranges including spawning sites on vertical walls of overhanging reefs where filamentous algae were densely distributed. Females visited a male's home range to release adhesive eggs into the dense algae. Males guarded multiple egg clutches, but rarely showed fanning behaviors or mouth cleaning to the eggs. Aquarium experiments showed that guarding males had no significant effect on egg development. Because of the favorable water exchange conditions around their spawning sites, male U. xenogrammus could avoid the energy costs for egg care.  相似文献   

2.
环境温度变化通过影响鸟类的行为进而使其活动区也发生变化,探讨三者之间的关联性有助于理解鸟类是如何通过行为调整以适应周围环境的变化,来满足自身的生理需求.本研究通过卫星跟踪的方法获得了在河南三门峡湿地越冬的31只大天鹅(Cygnus cygnus)详细位点数据,在ArcGIS和R语言中采用核密度估计法计算大天鹅的活动区面...  相似文献   

3.
BACKGROUND AND PURPOSE: Ivermectin is a common anthelmintic drug, widely used in laboratory rodents for treatment of pinworm and mite infestations. We evaluated the action of ivermectin on sensitive behavioral tasks in mice during treatment for mites within a barrier facility. METHODS: A total of 21 (5 males, 16 females) mice (129/SvEv) were used for measuring body weight, open field locomotor activity, and rotarod motor coordination. For acoustic startle and prepulse inhibition, 20 C57BL/6J and 29 AKR/J mice were studied. For the Morris water task, the same 20 C57BL/6J mice were studied. Ivermectin (0.08% sheep drench) was administered in the drinking water of the home cage for 8 weeks. Control groups received normal tap water in identical bottles. RESULTS: Ivermectin did not affect general health, body weight, motor coordination, swimming behavior, or spatial learning in several inbred strains of mice. However, it induced a small but significant effect on some sensitive behaviors. CONCLUSIONS: A cautious approach to initiating ivermectin treatment in mice should be used for sensitive behavioral experiments.  相似文献   

4.
Objective: This study examined sociodemographic and cultural determinants of away‐from‐home food consumption in two contexts and the influence of frequency of away‐from‐home food consumption on children's dietary intake and parent and child weight status. Methods and Procedures: Parents of children (N = 708) in grades K‐2 were recruited from 13 elementary schools in Southern California. Parents were asked through a questionnaire the frequency with which they eat meals away from home and the restaurant they frequented most often. The height and weight of the parents and their children were measured to calculate BMI. Results: Consuming foods at least once a week from relatives/neighbors/friends (RNF) homes was associated with children's dietary intake and children's risk for obesity. For example, children of parents with weekly or greater RNF food consumption drank more sugar‐sweetened beverages. Parents of families who ate at restaurants at least weekly reported that their children consumed more sugar‐sweetened beverages, more sweet/savory snacks, and less water compared with families who did not frequent restaurants this often. The type of restaurant visited did not affect diet intake or obesity. More acculturated families exhibited less healthy dietary behaviors than less acculturated families. Discussion: Restaurants remain an important setting for preventing child and adult obesity, but other settings outside the home need to be considered in future intervention research. This may especially involve eating in the homes of RNF.  相似文献   

5.
Synopsis Existence of home site fidelity and homing ability was established for Pseudotropheus aurora. Territorial males stayed up to 1 1/2 years within the same territories. Females showed long-term fidelity to certain places. Transplantation experiments revealed that P. aurora males home over distances of up to at least 2500 m but would not cross deep water. The territorial males of five other sympartic species returned from 1000 m to their territories. The mechanisms and functions of homing in cichlids are discussed.  相似文献   

6.

Background

Household water treatment (HWT) can improve drinking water quality and prevent disease if used correctly and consistently by vulnerable populations. Over 1.1 billion people report treating their water prior to drinking it. These estimates, however, are based on responses to household surveys that may exaggerate the consistency and microbiological performance of the practice—key factors for reducing pathogen exposure and achieving health benefits. The objective of this study was to examine how HWT practices are actually performed by households identified as HWT users, according to international monitoring standards.

Methods and Findings

We conducted a 6-month case study in urban (n = 117 households) and rural (n = 115 households) Peru, a country in which 82.8% of households report treating their water at home. We used direct observation, in-depth interviews, surveys, spot-checks, and water sampling to assess water treatment practices among households that claimed to treat their drinking water at home. While consistency of reported practices was high in both urban (94.8%) and rural (85.3%) settings, availability of treated water (based on self-report) at time of collection was low, with 67.1% and 23.0% of urban and rural households having treated water at all three sampling visits. Self-reported consumption of untreated water in the home among adults and children <5 was common and this was corroborated during home observations. Drinking water of self-reported users was significantly better than source water in the urban setting and negligible but significantly better in the rural setting. However, only 46.3% and 31.6% of households had drinking water <1 CFU/100 mL at all follow-up visits.

Conclusions

Our results raise questions about the usefulness of current international monitoring of HWT practices and their usefulness as a proxy indicator for drinking water quality. The lack of consistency and sub-optimal microbiological effectiveness also raises questions about the potential of HWT to prevent waterborne diseases.  相似文献   

7.
Displacement of juvenile Atlantic salmon Salmo salar within an artificial stream was either spontaneous (fish left areas of shallow water in response to experimental reduction in water level) or imposed (fish were removed by the experimenter from areas of shallow water and placed at a distance from their home site). Prior to displacement, the fish showed a high degree of site fidelity in terms of preferential use of specific areas within the stream, but the extent to which this persisted once they had left/been removed from their preferred sites was variable. Direction of displacement was not a critical factor, but homing was significantly less likely to occur following spontaneous as opposed to imposed displacement. In the case of imposed displacement, fish that were more strongly site attached prior to displacement were more likely to return to their home site after this manipulation.  相似文献   

8.
Despite the persistent use of the word "solitary" to describe nocturnal primate social behavior, increasing numbers of studies are revealing sophisticated levels of social interactions among nocturnal primates. This study explores the relationships among 11 adult Mysore slender lorises (Loris lydekkerianus lydekkerianus) studied over 10(1/2) months in Tamil Nadu, India. When all observations regarding dependent offspring are excluded, the animals spent on average 38% of their activity in various forms of neutral, affiliative, and agonistic behaviors. Affiliative behaviors were the most common type of social interaction, and males in general were more social than females. Low values for Cole's index (CI) of association emphasize that females rarely interacted with same-sex conspecifics, but commonly interacted with males. In turn, males also formed strong affiliative relationships with other adult males. This index also indicates that levels of affiliation are strongest among animals that share sleeping sites. The Hinde index (HI) suggests that males control proximity to females more than the reverse. A female's tolerance of multiple males in her home range and at a sleeping site may be related to high spatial variability of food resources. Such resources may constrain females with costly reproductive strategies (up to two sets of twins per annum) to a small home range. With their larger home ranges, males may be able to monopolize females by initiating social interactions, and also provide a benefit to females by contributing to parental care.  相似文献   

9.

Background

Diarrhea is one of the leading causes of mortality in young children. Diarrheal pathogens are transmitted via the fecal-oral route, and for children the majority of this transmission is thought to occur within the home. However, very few studies have documented enteric pathogens within households of low-income countries.

Methods and Findings

The presence of molecular markers for three enteric viruses (enterovirus, adenovirus, and rotavirus), seven Escherichia coli virulence genes (ECVG), and human-specific Bacteroidales was assessed in hand rinses and household stored drinking water in Bagamoyo, Tanzania. Using a matched case-control study design, we examined the relationship between contamination of hands and water with these markers and child diarrhea. We found that the presence of ECVG in household stored water was associated with a significant decrease in the odds of a child within the home having diarrhea (OR = 0.51; 95% confidence interval 0.27–0.93). We also evaluated water management and hygiene behaviors. Recent hand contact with water or food was positively associated with detection of enteric pathogen markers on hands, as was relatively lower volumes of water reportedly used for daily hand washing. Enteropathogen markers in stored drinking water were more likely found among households in which the markers were also detected on hands, as well as in households with unimproved water supply and sanitation infrastructure.

Conclusions

The prevalence of enteric pathogen genes and the human-specific Bacteroidales fecal marker in stored water and on hands suggests extensive environmental contamination within homes both with and without reported child diarrhea. Better stored water quality among households with diarrhea indicates caregivers with sick children may be more likely to ensure safe drinking water in the home. Interventions to increase the quantity of water available for hand washing, and to improve food hygiene, may reduce exposure to enteric pathogens in the domestic environment.  相似文献   

10.
一只长江江豚妊娠期昼间行为及其时间分配   总被引:1,自引:0,他引:1  
长江江豚(Neophocaena phocaenoides asiaeorientalis Pilleri and Gihr,1972)属于哺乳纲(Mammalia)、鲸目(Cetacea),是仅分布于长江中下游及其附属湖泊中的惟一且相对独立的一个江豚淡水亚种(高安利和周开亚,1995),也是中国水域中三个江豚种群中最为濒危的一个亚种,<中国濒危动物红皮书·兽类>也将其列为濒危级(汪松,1998).  相似文献   

11.
The neuropeptide oxytocin regulates a wide variety of social behaviors across diverse species. However, the types of behaviors that are influenced by this hormone are constrained by the species in question and the social organization that a particular species exhibits. Therefore, the present experiments investigated behaviors regulated by oxytocin in a eusocial mammalian species by using the naked mole-rat (Heterocephalus glaber). In Experiment 1, adult non-breeding mole-rats were given intraperitoneal injections of either oxytocin (1 mg/kg or 10 mg/kg) or saline on alternate days. Animals were then returned to their colony and behavior was recorded for minutes 15–30 post-injection. Both doses of oxytocin increased huddling behavior during this time period. In Experiment 2, animals received intraperitoneal injections of either oxytocin (1 mg/kg), an oxytocin-receptor antagonist (0.1 mg/kg), a cocktail of oxytocin and the antagonist, or saline across 4 testing days in a counterbalanced design. Animals were placed in either a 2-chamber arena with a familiar conspecific or in a small chamber with 1 week old pups from their home colony and behaviors were recorded for minutes 15–30 post-injection. Oxytocin increased investigation of, and time spent in close proximity to, a familiar conspecific; these effects were blocked by the oxytocin antagonist. No effects were seen on pup-directed behavior. These data suggest that oxytocin is capable of modulating affiliative-like behavior in this eusocial species.  相似文献   

12.
Between 1968 and 1980 fractures occurred in 56 of 284 patients treated by home haemodialysis in the Sheffield area for longer than one year. Patients sustained four times as many fractures while using dialysate prepared with water containing more than 1.0 mumol aluminium per 1 (2.7 micrograms/100 ml) than while using water containing a smaller concentration. When aluminium was removed from water by deionisation the incidence of fractures diminished during the next year and no patient developed dialysis encephalopathy. These findings show that 1.0 mumol/l is a safe maximum concentration of aluminium in water for use in home haemodialysis. It can be detected by the colorimetric aluminium analyses used by many water authorities. When financial resources are limited it is expedient to reserve aluminium analyses by electrothermal atomic absorption for plasma from patients receiving regular haemodialysis. Ingestion of aluminium hydroxide contributes significantly to the increased plasma aluminium concentration of these patients.  相似文献   

13.
车俭  郑洁  蒋娅  金毅  乙引 《植物生态学报》2020,44(10):1007-1014
常绿和落叶木本被子植物是组成东亚地区亚热带阔叶林的两个主要植物类群。探索常绿和落叶木本被子植物的生态位差异, 对于推测亚热带阔叶林群落的生物多样性维持机制, 具有重要意义。该研究采用线性回归模型和Mantel检验多元回归等统计手段, 分析了中国亚热带地区8个森林动态监测样地的常绿和落叶木本被子植物谱系和生态习性差异。主要结果: (1)该研究的788个被子植物分类单元的叶习性(常绿和落叶)具有一定的谱系保守性。常绿和落叶植物对光照、温度、水分、土壤反应和土壤肥力因子的生态习性均有差异, 表现为常绿植物偏好较低的光照和土壤pH, 以及较高的温度、水分和土壤肥力; 落叶植物则相反。(2)样地内落叶较常绿植物的种间谱系散布更收敛, 但生态习性散布更发散; 样地间落叶较常绿类群的谱系组成差异更小, 但生态习性差异更大; 样地间落叶类群的谱系组成差异随年平均气温差异的增大而增大。(3)落叶/常绿植物物种数量的比例随年平均气温升高而降低, 而旱季持续时间和年降水量等因子的影响不明显。该研究证实了我国亚热带地区8个森林动态监测样地内的常绿和落叶木本被子植物在谱系和生态习性上均存在巨大差异, 生态位分化在很大程度上是促进亚热带阔叶林群落内生物多样性维持的重要机制。  相似文献   

14.
The purpose of the present study was to evaluate an intervention to prevent weight gain among households (HHs) in the community. Ninety HHs were randomized to intervention or control group for 1 year. Intervention consisted of six face-to-face group sessions, placement of a television (TV) locking device on all home TVs, and home-based intervention activities. Measures were collected in person at baseline and 1 year. Weight, height, eating behaviors, physical activity (PA), and TV viewing were measured among HH members ages ≥ 12 years. Follow-up rate at 1 year was 96%. No significant intervention effects were observed for change in HH BMI-z score. Intervention HHs significantly reduced TV viewing, snacks/sweets intake, and dollars per person spent eating out, and increased (adults only) PA and self-weighing frequency compared with control HHs. A 1 year obesity prevention intervention targeting entire HHs was effective in reducing TV viewing, snack/sweets intake and eating out purchases. Innovative methods are needed to strengthen the home food environment intervention component. Longer intervention durations also need to be evaluated.  相似文献   

15.
Freezing and melting transitions of cellular water in embryonic axes and cotyledonary tissues of recalcitrantQuercus rubra(red oak) seeds were compared under slow and rapid cooling conditions. The relevance of desiccation sensitivity (critical water content) and state/phase transition behaviors to cryopreservation was examined. Under a slow to intermediate cooling condition (≤10°C min−1), unfrozen water content in the tissues decreased to less than the critical water content, resulting in a dehydration damage. Under a rapid cooling condition (>100°C min−1) using liquid nitrogen (LN2), freeze-induced dehydration damage could be avoided if the initial water content was >0.50 g g−1dry wt. However, at water content >0.50 g g−1dry wt, the vitrified cellular matrix was highly unstable upon warming at 10°C min−1. These results offered a theoretical explanation on the difficulty for successful cryopreservation of recalcitrant red oak embryonic axes. A complete state/phase transition diagram for red oak axes was constructed, and a vitrification-based cryopreservation protocol that employed predehydration and rapid cooling was examined. State/phase transition behaviors of cellular water are important parameters for cryopreservation; however, vitrification alone was not sufficient for seed tissues to survive the cryopreservation condition.  相似文献   

16.
流速对红鳍银鲫幼鱼游泳状态的影响   总被引:7,自引:0,他引:7  
在28℃水温下,采用特制的鱼类游泳行为测定装置,研究体重(125.94±13.87)g的红鳍银鲫(Barbodes schwanenfeldi)幼鱼在0.0m/s(对照组)和0.1m/s、0.3m/s、0.5m/s3种流速下的游泳行为。结果表明,从0.0~0.3m/s,红鳍银鲫幼鱼平均趋流率和摆尾频率均随着流速的增加而增大,而0.5m/s组在90min内随时间延长而下降。红鳍银鲫游泳状态明显受到所处流速的影响,在静水对照组以"逆流前进"和"顺流而下"为主,两者共占总观察时间的98%以上;各流速组均以逆流静止为主,且随着流速的增大,逆流静止所占时间比例从45.8%增加至81.3%,而逆流前进所占时间比例由24.1%减至5%以下;逆流后退所占时间比例以0.1m/s组最大,为16.4%;顺流而下的比例随着流速增大先减小后增大,3个流速组依次为13.7%、2.1%和10.9%。红鳍银鲫幼鱼的游泳速度(V)和摆尾频率(TBF)在逆流前进及逆流静止两种游泳状态下呈线性正相关,而在逆流后退和顺流而下两种状态下两者没有显著相关。  相似文献   

17.

Background

The aim of this study was to assess the feasibility of injury specific home safety investigation and to examine the home safety status focused on burn related safety in a rural population in the North-West of Iran.

Methods

A cross-sectional study was conducted on 265 rural households of rural Meshkinshahr, Iran. Cluster sampling method was used in 38 clusters with 7 households in each cluster. Clusters were selected on a probability proportional to size (PPS) basis using the available health census database called D-Tarh. Data were analyzed using the statistical software package STATA 8.

Results

Possible risks were explored in fields of house structure; cooking and eating attitudes and behaviors; cooking appliances, specific appliances such as picnic gas burners, valors (traditional heaters), samovars (traditional water boilers), and air-heating appliances. Many safety concerns were explored needing to draw the attention of researchers and public health policy makers.

Conclusion

Injury specific home safety surveys are useful and may provide useful information for safety promotion interventions.  相似文献   

18.
Inappropriate behaviors of potential guide dogs (puppies) for the blind and coping behaviors of their adult female raisers (puppy walkers: PWs) were videotaped in their play situation at home from when the puppies were 2-11 or 12 months of age. The frequency of inappropriate behavior decreased with an increase in the puppies' age, suggesting that human-dog relationships became friendlier. The PWs tended to use moderate coping behaviors to stop the inappropriate behaviors of the puppies. Rejecting interaction with the puppies was effective for stopping the puppies from biting the PWs. Forcible stopping was effective for stopping the puppies from damaging objects. Not responding to the puppies was effective for stopping the puppies from biting the PWs, barking/growling and damaging objects.  相似文献   

19.
Although social housing is desirable for social species of nonhuman primates, circumstances arise whereby social housing is precluded (for example, certain kinds of infectious disease or toxicologic research, when the health of the animal(s) would be compromised by social housing, and animals which respond behaviorally in an inappropriate manner to social housing). Nonsocial alternatives that provide increased environmental complexity to the home cage should then be considered. Nonsocial "environmental enrichment" schemes can be designed to enhance the expression of an individually housed nonhuman primate's locomotive/postural, manipulative, and foraging behaviors. In this way, nonsocial, but species-typical, behaviors can be promoted in the single cage housing condition.  相似文献   

20.
E Meller  F Bordi  K Bohmaker 《Life sciences》1989,44(15):1019-1026
Irreversible inactivation of both D-1 and D-2 dopamine (DA) receptors by N-ethoxycarbonyl-2-ethoxy-1,2-dihydroquinoline (EEDQ) resulted in complete loss of stereotypy response to R-(-)-N-propylnorapomorphine (NPA; 0.1-1.0 mg/kg, s.c.) 24 hr later. Stereotyped sniffing recovered much more rapidly than oral behaviors. The D-2 antagonist sulpiride (200 mg/kg) and the putatively nonselective antagonist cis-flupenthixol (2 mg/kg), administered prior to EEDQ, prevented the loss of NPA-induced sniffing but only partially protected against loss of oral behaviors 24 hr later. Complete protection of both behaviors was seen after pretreatment with a combination of sulpiride and the selective D-1 antagonist SCH 23390 (1 mg/kg); pretreatment with the selective D-1 antagonist SCH 23390 alone, however, did not modify the rate of recovery of either behavioral response. The results suggest that either different populations of DA receptors mediate expression of these behaviors or stimulation of a small fraction of the total DA receptor pool may be sufficient to elicit sniffing but not oral responses. Furthermore, maintaining a normal complement of D-2 rather than D-1 receptors appears to be a critical determinant for the elicitation of these behaviors.  相似文献   

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