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1.
Peter Lewis 《Journal of bioethical inquiry》2007,4(1):51-55
The display of personal photographs in hospital is a common practice that has yet to be rigorously examined. The photographs
displayed are subject to interpretation by the viewer and may lead to misunderstandings or miscommunication if clarification
of meaning is not sought. This paper explores a range of possible meanings that the display of photographs in hospital may
hold, based on a case study of a 15 year old boy hospitalised with a life threatening illness. Further research is needed
into the actual meanings attributed to the display of photographs in hospital by patients and family members. 相似文献
2.
3.
This study aimed to identify influences, attitudes and actions of nursing staff in relation to oral care for people with disabilities. Individual in-depth interviews of twenty two nursing staff were conducted. Enabling and inhibiting factors in the reported attitudes, approaches and practices were identified. The main enabling factors were that nursing staff saw mouth care as part of their role and took an empathic and caring approach to its delivery. They aimed to make the residents socially acceptable, improve their self-esteem and make their mouths clean and breath fresher. Inhibiting factors were: a lack of training, time constraints associated with workload, and poor understanding of the processes causing dental disease. The study concludes that improvements in oral care by nursing staff can be encouraged by working with nurses'attitudes, values and beliefs. Once the desired behaviour change has occurred then the lack of knowledge can be addressed. 相似文献
4.
Summary . We propose a fully inferential model-based approach to the problem of comparing the firing patterns of a neuron recorded under two distinct experimental conditions. The methodology is based on nonhomogeneous Poisson process models for the firing times of each condition with flexible nonparametric mixture prior models for the corresponding intensity functions. We demonstrate posterior inferences from a global analysis, which may be used to compare the two conditions over the entire experimental time window, as well as from a pointwise analysis at selected time points to detect local deviations of firing patterns from one condition to another. We apply our method on two neurons recorded from the primary motor cortex area of a monkey's brain while performing a sequence of reaching tasks. 相似文献
5.
In extant brachiopods, parental brooding of the larvae occurs exclusively within Rhynchonelliformea. Methods of larval protection range from simple retention of the larvae within the mantle cavity, to sophisticated brood care within highly specialized brood pouches found in Argyrotheca and Joania (Terebratulida, Megathyridoidea), Gwynia (Terebratulida, Gwynioidea), and all Thecideoidea (Thecideida). Previous studies on the reproductive biology of Argyrotheca yielded contrasting results on the epithelial origin of the brood pouches in this genus. Here, representatives of different species of Argyrotheca from the Belize Barrier Reef were examined using histological section series. Brood pouches of four species, A. cf. schrammi and Argyrotheca sp. 1–3, are of the same basic structure, formed by invaginations of the anterior body wall and connected to the visceral cavity via the metanephridia. The same four species are simultaneously hermaphroditic, suggesting that fertilization is achieved, at least partly, through selfing. One species, Argyrotheca rubrocostata, differs significantly from all others as it has no brood pouch and gonochoric gonads. Thus, the presence of brood pouches and simultaneous hermaphroditism are concluded to be correlated within Megathyridoidea and proposed to be homologous traits of Joania and several but not all species of Argyrotheca, questioning the monophyletic status of both genera. In contrast to the brood pouches of Thecideoidea, lophophoral epithelium is not involved in the formation of the pouches of Argyrotheca and Joania. Therefore, megathyridoid and thecideoid brood pouches are not homologous but evolved independently within rhynchonelliform brachiopods. All brachiopods with brood pouches share a micromorphic form and a short life span, limiting the space and time available for gamete and larval development. We suggest that the brood pouches and the hermaphroditic gonads of Argyrotheca spp. and Joania compensate these limitations by minimizing the loss of gametes and larvae, and by maximizing the chances of successful fertilization. J. Morphol., 2013. © 2013 Wiley Periodicals, Inc. 相似文献
6.
Intrinsic processes are assumed to underlie life history expression and trade‐offs, but extrinsic inputs are theorised to shift trait expression and mask trade‐offs within species. Here, we explore application of this theory across species. We do this based on parentally induced embryo temperature as an extrinsic input, and mass‐specific embryo metabolism as an intrinsic process, underlying embryonic development rate. We found that embryonic metabolism followed intrinsic allometry rules among 49 songbird species from temperate and tropical sites. Extrinsic inputs via parentally induced temperatures explained the majority of variation in development rates and masked a relationship with metabolism; metabolism explained a minor proportion of the variation in development rates among species, and only after accounting for temperature effects. We discuss evidence that temperature further obscures the expected interspecific trade‐off between development rate and offspring quality. These results demonstrate the importance of considering extrinsic inputs to trait expression and trade‐offs across species. 相似文献
7.
In temperate waters of southern Japan, mouthbrooding males of the cardinal fish Apogon doederleini sometimes ate their entire brood within a day of spawning. In spite of annual variation in age structure and length of the breeding season, however, the annual cannibalism rate (broods cannibalized to total broods spawned) was nearly constant, 12–16%. Fish 1 year old frequently cannibalized early broods of the season, especially the first brood, whereas the cannibalism rate by 2 year-old fish did not vary within the season. In contrast, the cannibalism by older males increased late in the season. This tendency was attributed to their different allocation patterns to growth and reproduction. For 1 year-old fish, which can enhance future reproductive success by growth and cannibalizing on early broods instead of mouthbrooding (at relatively low temperatures), this may be a tactic for investing energy in growth. For fish 3 years, which have more breeding cycles and grow little, cannibalizing late broods may be energetic compensation for their poor somatic condition. No seasonal variation of cannibalism by 2 year-old fish can be explained by their intermediate nature of growth and reproduction. Multiple mate availability is one factor facilitating the cannibalism by 2 and 3 + year-old fish whose operational sex ratio is female-biased. 相似文献
8.
The relationship between nitrification potential and nitrogen accumulation was studied in an early successional sere on Mt.
Fuji. Soil organic nitrogen accumulated with the invasion ofPolygonum cuspidatum and successively withMiscanthus oligostachyus and other species. Laboratory incubation experiments showed a higher nitrification potential at theM. oligostachyus state. The numbers of nitrifying bacteria increased with the progress of succession. No significant difference in nitrate
reductase activity was found between pioneer and succeeding species. The soil solution at theM. oligostachyus stage contained a lower level of nitrate than rainwater, while that of the bare ground and theP. cuspidatum stage contained a higher nitrate level than rainwater. It was concluded that the high nitrate levels in the soil solution
of the bare ground and theP. cuspidatum stage were due to lower nitrate-absorbing activity, leading to loss of nitrogen with precipitation, while the lower nitrate
levels at theM. oligostachyus stage when higher nitrification activity occurred were due to higher nitrate-absorbing activity, preventing net loss of nitrogen
from the ecosystem. 相似文献
9.
Dendrobatid frogs perform a unique mode of parental care, ranging from egg attendance and tadpole transport to tadpole feeding. It is hypothesized that a behaviour in which the egg attending parent remains with the cluch is the most primitive condition. In more advanced forms or parental care, the male is able to attend several clutches of eggs. Tadpole attendance and feeding, finally, started as deceit; the male induced the female to lay eggs into a bromeliad leaf axil already occupied by a larva. Costs and benefits of the different modes of parental care and possible alternative reproductive tactics are discussed. 相似文献
10.
J Dupont J F Rodes J Berreur-Bonnenfant M C Carre A Tekitek P Berreur 《Biology of the cell / under the auspices of the European Cell Biology Organization》1989,67(2):141-146
Farnesylacetone (C18 H30 0) is a male hormone extracted from the androgenic gland of crab, Carcinus maenas. Appropriate enzymatic assays, as well as spectrophotometric studies, indicate that micromolar concentrations of farnesylacetone interact with the electron transport pathway of rat liver mitochondria. By the use of artificial electron donors and electron acceptors, it is shown that farnesylacetone immediately inhibits the electron transfer within complex I (NADH ubiquinone reductase activity) and complex II (succinate ubiquinone reductase activity). It is proposed that farneylacetone could interact with these two complexes of the respiratory chain at the level of the iron-sulfur centers implicated in the dehydrogenase activities. These observations are compared with the results obtained with terpenic molecules which interact with mitochondrial respiration. 相似文献