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31.
Penaeid and carid communities were assessed in St Lucia over a wide range of saline conditions, water level conditions and mouth states, including a six-month marine connection and various connections to the Mfolozi Estuary. Samples were collected biannually in spring and autumn from November 2004 to May 2012 using seine nets. Seven penaeid and seven carid species were recorded, of which Palaemon pacificus, P. peringueyi, Penaeus indicus and Metapenaeus monoceros were the most abundant. The decline from 2004 to 2007 in both species recorded and densities of freshwater, estuarine and marine species during the initial closed period was linked to increased salinity, lack of recruitment and reduced estuarine surface area. Increased wave action and high seas following Cyclone Gamede opened the mouth in March 2007 after a 57-month closed period, resulting in recruitment of marine species, predominantly P. indicus, followed by a decline in densities after reclosure in August 2007. Increases in marine and freshwater species were evident after Mfolozi flood connections during 2008, 2009 and 2010. Highest densities were recorded after breaching in 2007 and after flood connections, highlighting the importance of a marine link to maintain the recruitment of penaeid species.  相似文献   
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The spring phytoplankton bloom and copepod grazing were studied at a coastal and offshore station in the western Irish Sea during 1997. Maximum chlorophyll standing stocks of 132.8 mg m-2 inshore and 199.4 mg m-2 offshore were measured in late April. At that time, mean water column temperatures were 10 and 8C at the coastal and offshore station, respectively. Spring bloom production at the coastal station was estimated as 31.2 g C m-2 and was dominated by the diatom Guinardia delicatula. Offshore, production was 28.2 g C m-2 and the bloom was composed of small (10 m) phytoflagellates and the silicoflagellate Dictyocha speculum. Maximum copepod abundance (189 and 544 x 103 individuals m-2, inshore and offshore, respectively) coincided with the spring bloom. Pseudocalanus and Temora ingestion rates were derived from measurements of gut pigment fluorescence, and were found to vary during the course of the spring bloom as a result of changes in gut content. Grazing by late copepodite and adult Pseudocalanus and Temora was variable inshore, but overall accounted for 17% of bloom production. Offshore, 22% of bloom production was grazed with maximum grazing (76% of daily production) occurring at the end of the bloom. Large copepod species were not major grazers of the spring bloom. Greater utilization of spring bloom production by copepods in the western Irish Sea compared to regions of the North Sea is attributed to differences in population size at the time of the bloom.   相似文献   
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We investigated the effects of audiovisual compound training on song learning in zebra finches, Taeniopygia guttata. In the first experiment, presentation of a stuffed adult zebra finch male was found to be reinforcing to zebra finch males in an operant task. In a separate experiment, zebra finch males were reared without their father from day 7 after hatching onwards. Between 35 and 76 days, they were placed in isolation and exposed to taped songs of a zebra finch male, according to a random schedule (20 presentations/h). For half of the birds, presentation of the song coincided with presentation of a stuffed zebra finch male. For the remaining birds, each presentation of the song was followed by presentation of a stuffed male. The birds were subsequently isolated until day 142, when their own songs were recorded and analysed. Birds in both groups shared significantly more song elements with their tutor songs than with an unfamiliar song. There was no significant difference in song learning between the groups. These results confirm that zebra finches can learn part of their songs from taped tutor songs. Furthermore, simultaneous presentation of the tutor song and a relevant, salient visual stimulus is not superior to sequential presentation. Copyright 1999 The Association for the Study of Animal Behaviour.  相似文献   
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Background

The objective of the present study was to reveal patterns in the treatment of health conditions in a Quechua-speaking community in the Bolivian Andes based on plant use data from traditional healers and patient data from a primary health care (PHC) service, and to demonstrate similarities and differences between the type of illnesses treated with traditional and biomedical health care, respectively.

Methods

A secondary analysis of plant use data from semi-structured interviews with eight healers was conducted and diagnostic data was collected from 324 patients in the community PHC service. Health conditions were ranked according to: (A) the percentage of patients in the PHC service diagnosed with these conditions; and (B) the citation frequency of plant use reports to treat these conditions by healers. Healers were also queried about the payment modalities they offer to their patients.

Results

Plant use reports from healers yielded 1166 responses about 181 medicinal plant species, which are used to treat 67 different health conditions, ranging from general symptoms (e.g. fever and body pain), to more specific ailments, such as arthritis, biliary colic and pneumonia. The results show that treatment offered by traditional medicine overlaps with biomedical health care in the case of respiratory infections, wounds and bruises, fever and biliary colic/cholecystitis. Furthermore, traditional health care appears to be complementary to biomedical health care for chronic illnesses, especially arthritis, and for folk illnesses that are particularly relevant within the local cultural context. Payment from patients to healers included flexible, outcome contingent and non-monetary options.

Conclusion

Traditional medicine in the study area is adaptive because it corresponds well with local patterns of morbidity, health care needs in relation to chronic illnesses, cultural perceptions of health conditions and socio-economic aspects of health care. The quantitative analysis of plant use reports and patient data represents a novel approach to compare the contribution of traditional and biomedical health care to treatment of particular health conditions.  相似文献   
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Background

Although Morbillivirus and Toxoplasma gondii have emerged as important pathogens for several cetaceans populations over the last 20 years, they have never been identified together in a Mysticete. In particular, morbilliviral infection has been never described in the Mediterranean fin whale population.

Case presentation

On January 2011 an adult male of fin whale (Balaenoptera physalus) stranded along the Tyrrhenian coastline of Italy. During necropsy, tissue samples from heart, skeletal muscle, mesenteric lymph nodes, liver, spleen, lung, and kidney were collected and subsequently analyzed for Morbillivirus and Toxoplasma gondii by microscopic and molecular methods. Following the detailed necropsy carried out on this whale, molecular analysis revealed, for the first time, the simultaneous presence of a Dolphin Morbillivirus (DMV) and T. gondii infection coexisting with each other, along with high organochlorine pollutant concentrations, with special reference to DDT.

Conclusion

This report, besides confirming the possibility for Mysticetes to be infected with DMV, highlights the risk of toxoplasmosis in sea water for mammals, already immunodepressed by concurrent factors as infections and environmental contaminants.  相似文献   
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Gene delivery from tissue engineering scaffolds can induce expression of tissue inductive factors to stimulate the cellular processes required for regeneration. Transfected cells secrete diffusible proteins that can create local concentration gradients, depending on the number, distribution, and expression level of transfected cells. These gradients are linked to cellular organization and tissue architecture during embryogenesis. In this report, we investigate neuronal architecture and neurite guidance in response to the concentration gradients achieved by localized secretion of a neurotrophic factor from transfected cells. A co‐culture model was employed to examine neuronal responses to multiple transfection profiles, which affects the local concentration of secreted nerve growth factor (NGF). Neuronal architecture, as defined by number of neurites per neuron and length of neurites, was influenced by the transfection profile. Low levels of NGF production by few transfected cells produced longer primary neurites with less branching relative to the higher expression levels or increased numbers of transfected cells. Furthermore, for low NGF production by few transfected cells, the growth cone of the axons was marked by longer extensions and larger surface area, suggesting the presence of a guidance cue. Control studies with varying NGF concentrations did not substantially alter the neuronal architecture, further supporting an effect of localized concentration gradients, and not simply the concentration. Mathematical modeling of NGF diffusion was employed to predict the concentration gradients produced by the transfection profiles, and the resultant gradients were correlated to the cellular response. This report connects the transfection profile, concentration gradients, and the resulting cellular architecture, suggesting a critical design consideration for the application of gene delivery to regenerative medicine. Biotechnol. Bioeng. 2009;103: 1023–1033. © 2009 Wiley Periodicals, Inc.  相似文献   
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