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OBJECTIVE--To monitor nutritional status and food security in order to identify nutritionally vulnerable groups. DESIGN--Members of five different household groups (urban and rural residents, displaced people in collective centres and private accommodation, elderly people living without younger family) and all residents of two old people''s homes were prospectively followed. Households were selected from 20 local communities and nine collective centres. SETTING--Monitoring carried out in three besieged areas of Bosnia-Hercegovina (Sarajevo, Tuzla, and Zenica). SUBJECTS--1739 individuals sampled. INTERVENTIONS--Data collected every month from December 1993 to May 1994. Information on household food security was collected through structured questionnaires. All subjects were weighed and their heights measured. Weight for age Z scores were calculated for children; body mass index was calculated for adults and elderly people. RESULTS--From December 1993 to February 1994, before a temporary cease fire, access to food was reduced. In February 1994 no significant signs of undernutrition were detected among children or adults, but elderly people had higher than expected levels of undernutrition (15.5% with body mass index < 18.5), a higher rate of weight loss than adults (1.2 kg over two months), and a higher prevalence of self reported illness. CONCLUSIONS--Elderly people in Bosnia-Hercegovina are at greater risk of undernutrition than other age groups. Undernutrition may be precipitated in elderly people by sickness, cold, stress, and problems related to food preparation. The health and welfare of elderly people during the emergency in Bosnia-Hercegovina require special attention, and integrated age care programmes are needed.  相似文献   

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In 2005, Hurricanes Katrina and Rita clearly revealed that even in the United States the welfare of companion animals and nonhuman animals in the wild, zoo, or aquarium was not considered within the evacuation plans for their human caretakers (owners). The lack of proper planning and trained individuals resulted in a huge loss of animal life as well as suffering and trauma to both animals and their owners. The present Canadian Federal Emergency Response Plan does not have adequate procedures for the evacuation of animals together with their owners, nor do Canada or the provinces and territories have a plan in place that consists of properly trained and equipped individuals to respond to this aspect of disaster management. The Canadian Veterinary Reserve (CVR) was thus organized at a national level to respond properly to disasters or emergencies of all types and thereby reduce animal suffering and loss of life. This article describes the formation of the CVR and its anticipated national role in addressing animal welfare during times of catastrophic need.  相似文献   

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Ribozyme catalysis revisited: is water involved?   总被引:2,自引:0,他引:2  
Walter NG 《Molecular cell》2007,28(6):923-929
Enzymatic catalysis by RNA was discovered 25 years ago, yet mechanistic insights are emerging only slowly. Thought to be metalloenzymes at first, some ribozymes proved more versatile than anticipated when shown to utilize their own functional groups for catalysis. Recent evidence suggests that some may also judiciously place structural water molecules to shuttle protons in acid-base catalyzed reactions.  相似文献   

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Desert truffles (mycorrhizal hypogeous Ascomycota) are found in arid and semi-arid areas of the globe and have great ecological and economic importance. Terfezia is undoubtedly the most diversified of all desert truffle genera, but its taxonomy is far from resolved. Specifically, the large number of newly described species plus the high intraspecific morphological variability observed within some Terfezia lineages as rendered the use of molecular techniques mandatory for specimen's discrimination. But the subsequent increasing amount of sequence data produced also a huge number of undescribed taxa that required determination. We compiled and used the public available ITS data on Terfezia spp. on the custom-curated UNITE database to reconstruct the genus phylogeny. We found at least 17 distinct lineages within the genus and successfully resolved some of the more pressing taxonomic issues, namely the T. leptoderma/olbiensis complex and some misapplied synonymy. Based on this resolved phylogeny, and motivated by the recent new described species, we proposed an identification key to Terfezia genus highlighting the importance of morphological and ecological characterization.  相似文献   

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Acoustic individual discrimination has been demonstrated for a wide range of animal taxa. However, there has been far less scientific effort to demonstrate the effectiveness of automatic individual identification, which could greatly facilitate research, especially when data are collected via an acoustic localization system (ALS). In this study, we examine the accuracy of acoustic caller recognition in long calls (LCs) emitted by Bornean male orangutans (Pongo pygmaeus wurmbii) derived from two data-sets: the first consists of high-quality recordings taken during individual focal follows (N = 224 LCs by 14 males) and the second consists of LC recordings with variable microphone-caller distances stemming from ALS (N = 123 LCs by 10 males). The LC is a long-distance vocalization. We therefore expect that even the low-quality test-set should yield caller recognition results significantly better than by chance. Automatic individual identification was accomplished using software originally developed for human speaker recognition (i.e. the MSR identity toolbox). We obtained a 93.3% correct identification rate with high-quality recordings, and 72.23% with recordings stemming from the ALS with variable microphone-caller distances (20–420 m). These results show that automatic individual identification is possible even though the accuracy declines compared with the results of high-quality recordings due to severe signal degradations (e.g. sound attenuation, environmental noise contamination, and echo interference) with increasing distance. We therefore suggest that acoustic individual identification with speaker recognition software can be a valuable tool to apply to data obtained through an ALS, thereby facilitating field research on vocal communication.  相似文献   

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Transmission of infectious diseases is strongly influenced by who contacts whom. Despite the global distribution of tuberculosis (TB) in free-living wild mammal populations, little is known of the mechanisms of social transmission of Mycobacterium bovis between individuals. Here, I use a network approach to examine for correlations between five distinct types of intra- and intergroup social interaction and changes in TB status of 110 wild meerkats (Suricata suricatta) in five social groups over two years. Contrary to predictions, the most socially interactive animals were not at highest risk of acquiring infection, indicating that in addition to contact frequency, the type and direction of interactions must be considered when quantifying disease risk. Within social groups, meerkats that groomed others most were more likely to become infected than individuals who received high levels of grooming. Conversely, receiving, but not initiating, aggression was associated with M. bovis infection. Incidence of intergroup roving by male meerkats was correlated with the rovers themselves subsequently testing TB-positive, suggesting a possible route for transmission of infection between social groups. Exposure time was less important than these social interactions in influencing TB risk. This study represents a novel application of social network analysis using empirical data to elucidate the role of specific interactions in the transmission of an infectious disease in a free-living wild animal population.  相似文献   

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Hückelhoven R  Kogel KH 《Planta》2003,216(6):891-902
Reactive oxygen intermediates (ROIs) such as hydrogen peroxide (H(2)O(2)) and the superoxide anion radical (O*(2)(-)) accumulate in many plants during attack by microbial pathogens. Despite a huge number of studies, the complete picture of the role of ROIs in the host-pathogen interaction is not yet fully understood. This situation is reflected by the controversially discussed question as to whether ROIs are key factors in the establishment and maintenance of either host cell inaccessibility or accessibility for fungal pathogens. On the one hand, ROIs have been implicated in signal transduction as well as in the execution of defence reactions such as cell wall strengthening and a rapid host cell death (hypersensitive reaction). On the other hand, ROIs accumulate in compatible interactions, and there are reports suggesting a function of ROIs in restricting the spread of leaf lesions and thus in suppressing cell death. Moreover, in situ analyses have demonstrated that different ROIs may trigger opposite effects in plants depending on their spatiotemporal distribution and subcellular concentrations. This demonstrates the need to determine the particular role of individual ROIs in distinct stages of pathogen development. The well-studied interaction of cereals with fungi from the genus Blumeria is an excellent model system in which signal transduction and defence reactions can be further elucidated in planta. This review article gives a synopsis of the role of ROI accumulation, with particular emphasis on the pathosystem Hordeum vulgare L.- Blumeria graminis.  相似文献   

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We explore the mechanisms underlying the survival of a cohort of a coral reef fish ( Pomacentrus amboinensis ) in the first month following settlement. To investigate the extent to which growth history immediately following settlement is linked to early survival, we tagged 900 fish the morning after settlement and recaptured the survivors (n=34) 30 days later. Otolith analysis showed that individuals that were larger at settlement preferentially survived the first month in benthic habitats. We also compared these survivors with conspecifics from the same cohort that were collected at settlement and then outgrown in two experimental feeding conditions to produce fast- and slow-growing fish. Comparison of the growth histories exhibited by the survivors to those of experimental conspecifics revealed that survivors exhibited relatively slow initial growth during their first few days on the reef, followed by a period of accelerated growth. We suggest that the flexibility in growth potential of young fish allows for the occurrence of periods of rapid (and compensatory) growth that might enhance post-settlement survival by attenuating the high risk of size-selective mortality.  相似文献   

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An analysis of 503 articles published in the journal Theriogenology in 1984, 1987 and 1990 was conducted to identify research trends and researchers publishing in the journal. A 30.5% increase in the number of papers published was found for 1990. During the 3yr period studied, the United States and Canada accounted for 63.1% of the total number of articles published, followed by European countries with 14.3%, and by Asia with 12.0%. At least 1 paper was published from 41 countries. The United States, at the top of the list, increased its share from 16% in 1984 to 21% in 1990. The number of papers from Japan increased significantly while the percentage of participation from Europe declined. The female animal was the sole subject of 63.2% of the articles, and cattle were the most researched species, appearing in 44.3% of the studies. Although the estrous cycle was the most studied reproductive event in all 3 yr, there was also a trend for the popularity of this topic to decrease in favor of the subject fertilization. The number of authors per paper increased significantly over the years analyzed, as did the number of studies carried out in international cooperation. Institutes of higher education were represented in almost 70% of the papers, followed by research institutes (12.8%). The present analysis confirms the central role that the journal Theriogenology plays in the world-wide communication of research results in animal reproduction.  相似文献   

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The molecular mechanism of microtubule bundling has been enveloped in controversy for the past few years. At the centre of the debate are MAPs: are they necessary for the formation of microtubule bundles? In this article, Gloria Lee and Roland Brandt weigh the evidence and propose that microtubule stability might be the crucial factor in microtubule bundling. Perhaps then MAPs might act as spacer molecules between microtubules.  相似文献   

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The language abilities of captive chimpanzees give rise to the question of the existence and use of similar capabilities in wild chimpanzees. In Taï forest, wild chimpanzees seem to use drumming on buttressed trees to convey information an changes of travel direction, resting periods or both information combined. This communication system is iconic and relies on some arbitrariness. Emergence of symbol-like communication in wild chimpanzees seems mainly dependent on a low visibility environment, a high predation pressure and a large group of males.  相似文献   

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Utricularia purpurea is a rootless, free-floating, aquatic, carnivorous plant. I quantified biomass investment in U. purpurea traps and determined when traps begin to function and what they trap in natural habitats. In the Everglades of south Florida, plants invest an average of 26% of their biomass in bladders, although bladder number varies among sites and over time. Leaves begin trapping as they mature, and on leaves one whorl older than the most recently matured leaves, almost 100% of bladders have allochthonous material. Despite the substantial investment in their biomass, bladders capture few aquatic microinvertebrates. Almost all mature bladders, however, have living communities of algae, zooplankton, and associated debris. These results support the hypotheses that the important association in U. purpurea bladders is a mutualism rather than a predator-prey interaction and that the major benefit to the plants from bladders is derived from this community.  相似文献   

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I investigated whether the food choice in masked titi monkeys (Callicebus personatus melanochir) is selective with respect to energy or phytochemical characteristics of the food resources or opportunistic in relation to food abundance. I collected data on food choice and availability of food resources for 1 year in a forest fragment of the Atlantic rain forest in Eastern Brazil and analyzed main food items of the masked titi monkeys—fleshy fruit parts, seeds, and young leaves—for protein, lipid, carbohydrates, acid detergent fiber, tannin, and total energy content. A rich season of high food availability is distinct from a lean season with low food availability. Effects of food chemicals on food selection are not apparent. The main factor in food choice in both seasons is the abundance of the food items. Thus, for Callicebus personatus melanochir, opportunistic foraging seems to be the optimal strategy.  相似文献   

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