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81.
Hispanics and non‐Hispanics Americans participated in four sets of studies dealing with health‐oriented foods, with the goal to identify how they respond to food categories relevant in any cuisine. Each study comprised a conjoint analysis using 36 elements followed by a self‐profiling questionnaire to learn more about Hispanic and non‐Hispanic food responses to concepts for four different product categories (morning bread, bottled water, healthful salad dressing and popcorn as a snack). The study identified patterns of preference of marketing statements in the areas of health information, sensory characteristics, emotional benefits and endorsements. Conjoint utility values generated by both Hispanics and non‐Hispanic respondents correlated highly, suggesting that their food attitudes are quite similar for“non‐signature”products despite the differences in their original cuisines.  相似文献   
82.
Integration of mental health into primary care is essential in Kenya, where there are only 75 psychiatrists for 38 million population, of whom 21 are in the universities and 28 in private practice. A partnership between the Ministry of Health, the Kenya Psychiatric Association and the World Health Organization (WHO) Collaborating Centre, Institute of Psychiatry, Kings College London was funded by Nuffield Foundation to train 3,000 of the 5,000 primary health care staff in the public health system across Kenya, using a sustainable general health system approach. The content of training was closely aligned to the generic tasks of the health workers. The training delivery was integrated into the normal national training delivery system, and accompanied by capacity building courses for district and provincial level staff to encourage the inclusion of mental health in the district and provincial annual operational plans, and to promote the coordination and supervision of mental health services in primary care by district psychiatric nurses and district public health nurses. The project trained 41 trainers, who have so far trained 1671 primary care staff, achieving a mean change in knowledge score of 42% to 77%. Qualitative observations of subsequent clinical practice have demonstrated improvements in assessment, diagnosis, management, record keeping, medicine supply, intersectoral liaison and public education. Around 200 supervisors (psychiatrists, psychiatric nurses and district public health nurses) have also been trained. The project experience may be useful for other countries also wishing to conduct similar sustainable training and supervision programmes.  相似文献   
83.
Abstract Salt-stimulated ATPase activity in membrane preparations obtained from roots of Atriplex nummularia Lindl. at pH 5 was not suscep-tible to inhibition by KC1 or NaCl up to 450 mol m-3 but showed a broad peak of activity between 150 and 300 mol m?3. At pH 8 stimulation occurred at 50 mol m?3 but concentrations above 100 mol m?3 depressed activity below the level of the MgATPase activity. By contrast, preparations from roots of Pisum sativum L. at pH 5 showed maximal stimulation at 25 to 50 mol m?3 of NaCl or KC1; concentrations higher than 150 mol m?3 depressed activity below that of MgATPase activity. At pH 8 maximal stimulation was observed at 5 to 10 mol m?3 NaCl or KC1 while the threshold for inhibition was reduced to 15 mol m?3. With increasing salt concentrations the pH profiles for NaCl stimulation of Atriplex ATPase activity (expressed as the difference between treatment and control) showed a progressive displacement of the apparent optimum towards lower pH. The shift was not apparent when stimulation was expressed as a percentage of MgATPase activity. This shift may be accounted for if NaCl stimulated the monovalent salt-activated ATPase activity but simultaneously inhibited MgATPase activity.  相似文献   
84.
Trichoderma colonies were illuminated with a narrow light beamhaving a fixed length of 0.5 mm and varing widths. Spot conidiationcould be induced by a beam 0.1 mm or greater in width. Resultsindicated that some kind of joint perception of photoinductiontakes place among adjacent mycelial fields. (Received April 22, 1971; )  相似文献   
85.
ABSTRACT. Dictyostelium discoideum has a well characterized life cycle where unicellular growth and multicellular development are separated events. Development is dependent upon signal transduction mediated by cell surface, cAMP receptor/G protein linkages. Secreted cAMP acts extracellularly as a primary signal and chemoattractant. There are 4 genes for the distinct cAMP receptor subtypes, CAR1, CAR2, CAR3 and CAR4. These subtypes are expressed with temporally and spatially specific patterns and cells carrying null mutations for each gene have distinct developmental phenotypes. These results indicate an essential role for cAMP signalling throughout Dictyostelium development to regulate such diverse pathways as cell motility, aggregation (multicellularity), cytodifferentiation, pattern formation and cell type-specific gene expression.  相似文献   
86.
Wood, Rachel, Reitner, Joachim & West, Ronald R. 1989 01 15: Systematics and phylogenetic implications of the haploslerid stromatoporoid Newellia mira nov. gen. Lethaia, Vol. 22, pp. 85–93. Oslo. ISSN 0024–1164. The presence of spicules in a Palaeozoic stromatoporoid is here confirmed. Parallelopora mira Newell, 1935 from the Upper Carboniferous of the U.S.A. is redescribed as a calcified haplosclerid sponge with a primary siliceous spicule framework of isodictyally arranged styles, sub-tylostyles and strongyles and a secondary calcareous skeleton of stromatoporoid grade and probable aragonitic original mineralogy. P. mira is placed within a new genus Newellia, and family, the Newellidae. This form is postulated to have possessed large amounts of collagenous organic material which enveloped and bound the spicular framework in place. By the draping outline of the calcareous skeleton around the spicule framework and by analogy with the Recent demosponge genus Vaceletia, the calcareous skeleton is suggested to have formed by the direct mineralization of this collagenous template. Newellia mira nov. gen. is further proposed to constitute a member of a new clack of haplosclerid stromatoporoids, together with Euz-Miella erenoensis (Lower Cretaceous); a clade with some similarity to Recent non-calcified forms, e.g. Adocia. Most notably, the presence of different calcareous skeleton mineralogies and possibly microstructures in these two forms suggests the independent development of a calcareous skeleton at different times within this spicule clade. Demosponges appear to have produced calcareous skeletons independently in many different spicule clades. Calcified demosponges are now known from the Hadro-merida (Lower carboniferous; Upper Cretaceous - Recent), Axinellida (Upper Triassic - Lower Cretaceous; Upper Cretaceous; Recent), Poecilosclerida (Recent) as well as the Haplosclerida (Upper Carboniferous - Lower Cretaceous; Recent).□Upper Carboniferous, stromatoporoid, spicules, haplosclerid demosponges, calcareous skeleton biomineralization, demosponge clades, polyphyly.  相似文献   
87.
Azolla filiculoides Lam. causes serious weed problems in Britain, but its long-term survival might be limited by winter death. The aim of this study was to establish the low temperature responses and limitations of A. filiculoides sporophytes.
In the laboratory, normal vegetative growth was shown to continue at 5°C. Reddening of plants was a response to low temperature and high light conditions which could be prevented by shading. Adult plants died after short (18 h) exposure to −4°C but survived sub-zero temperatures >−4°C. Evidence was found of seasonal changes in chill tolerance, but not in freeze tolerance.
In outdoor culture, plants survived encasement in ice and air temperatures to −5°C. Additional evidence suggested that natural populations can readily survive air temperatures much lower than this. Microclimatic effects are likely to be responsible for this discrepancy between laboratory and outdoor culture results.
Three phenotyes were identified; survival, colonizing and mat forms.  相似文献   
88.
89.
Offspring size is a key characteristic in life histories, reflecting maternal investment per offspring and, in marine invertebrates, being linked to mode of development. Few studies have focused explicitly on intraspecific variation and plasticity in developmental characteristics such as egg size and hatching size in marine invertebrates. We measured over 1000 eggs and hatchlings of the marine gastropods Crepidula atrasolea and Crepidula ustulatulina from two sites in Florida. A common‐garden experiment showed that egg size and hatching size were larger at 23 °C than at 28 °C in both species. In C. ustulatulina, the species with significant genetic population structure in cytochrome oxidase I (COI), there was a significant effect of population: Eggs and hatchlings from the Atlantic population were smaller than those from the Gulf. The two populations also differed significantly in hatchling shape. Population effects were not significant in C. atrasolea, the species with little genetic population structure in COI, and were apparent through their marginal interaction with temperature. In both species, 60–65% of the variation in egg size and hatching size was a result of variation among females and, in both species, the population from the Atlantic coast showed greater temperature‐mediated plasticity than the population from the Gulf. These results demonstrate that genetic differentiation among populations, plastic responses to variation in environmental temperature, and differences between females all contribute significantly to intraspecific variation in egg size and hatching size. © 2010 The Linnean Society of London, Biological Journal of the Linnean Society, 2010, 99 , 489–499.  相似文献   
90.
Factors affecting the distribution of small mammals in an urban area   总被引:5,自引:0,他引:5  
We investigated the distribution of a range of small mammal species in five urban habitats in north‐west Bristol: residential gardens, woodlands, allotment gardens, scrub and a cemetery. Wood mouse Apodemus sylvaticus abundance in residential gardens was negatively related to the abundance of cats and the distance to the nearest patch of natural or seminatural vegetation. These results suggest that urban small mammal populations may be limited by predation and habitat fragmentation, although the effects of the latter may be offset by the availability of good quality gardens.  相似文献   
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