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61.
Objectives The aim of this study was to was to determine whether older adults perceive oral health as affecting their life quality and to identify variations in impacts in relation to socio-demographic factors, dental service utilisation and method of payment. Design This study formed part of the Office for National Statistics Omnibus Survey, which utilised a random probability sample of addresses from the British Postcode Address File (PAF). Setting 3,000 homes were selected from one hundred post sectors across Britain. Respondents were interviewed in their homes about how oral health affects their quality of life. Subjects 454 older people (aged 65 and over) took part in the survey. Main outcome measures The study group perceived oral health as impacting on their quality of life in general (negative and/or positive impact) (70%, 318), enhancing (53%, 241) and detracting (44%, 199) from their life quality. The most frequently perceived way in which oral health affects life quality was its effect on eating and comfort. Older people from higher socio-economic groups reported that oral health had a greater impact on their quality of life in general (positive and/or negative impacts), (OR=1.77,95% CI= 1.22,2.78) and specifically, enhancing their quality of life (OR=1.52, 95% CI=1.01,2.30). Those who reported attending the dentist within the last year perceived that their oral health enhanced their life quality (OR=1.55, 95% CI=1.01,2.38). Conclusions Socio-economic background and dental attendance pattern are associated with how older people perceived oral health as affecting quality of life. These findings may have implications for promoting regular dental attendance and auditing dental services for older people. 相似文献
62.
Keith D. Waddington 《Journal of insect physiology》1985,31(11):891-897
An aspect of the round dance, called RATE, was used as quantification of 15 honey bees' (Apis mellifera) perceptions of caloric costs and intakes experienced while foraging at artificial flowers. Caloric intake per floral visit (CALGAIN) was manipulated by varying sucrose concentration. Both flight and handling costs per floral visit (CALCOST) were manipulated. Multiple linear regression analysis was used to quantify the relationship between the dependent variable, RATE, and the two energy variables. There was significant variation among bees in dance behaviour. However, the absolute magnitude of the CLACOST coefficients tended to be larger than CALGAIN coefficients; bees may weight perceptions of costs in relation to intakes. Honey bees were presented with a series of binary choices between yellow or blue tubular artificial flowers in order to assess how cost-intake information is used to make choices among flowers. In eight experiments the 2 flowers had different combinations of volume of sucrose (intake) and tube depth (handling cost). Results are consistent with an assessment of rate of net caloric intake, although they are likely consistent with other possible assessments. 相似文献
63.
Distribution, endemism and threat status of freshwater fishes in the Western Ghats of India 总被引:4,自引:0,他引:4
Aim To study (1) the large-scale distribution patterns of freshwater fishes in the Western Ghats of India; (2) the endemism and uniqueness of the fishes in various zones; and (3) the threat status of fishes by categorizing them under low risk (LR), vulnerable (VU), endangered (EN) and critically endangered (CR). Location The Western Ghats of India. Methods The scientific literature describing the freshwater fishes of the Western Ghats was reviewed. Data describing the lists of the species were extracted and complied. The species accumulation curve was plotted using Michaelis–Menten-like equation. The Western Ghats was divided into six zones and similarity of the species was calculated using Jacquard's index. Results Literature to date records 288 species belonging to 12 orders, 41 families and 109 genera, of which 118 species are endemic and 51 are unique. However, the species accumulation curve shows that there might be 345 species in this region, indicating that 16% species have not been recorded to date. An analysis of the distribution pattern of fishes in the Western Ghats suggests that the southern region is more diverse than the northern and central regions. The southern region shows high endemism and high uniqueness while the northern region shows high endemism but less uniqueness. The similarity index between the zones indicates that as the distance between the zones increases similarity decreases. The status of 105 of 288 species was not known due to data deficiency but among the remaining 183 species, 58 species were categorized as LR, 41 as VU, 54 as EN, 24 as CR while the remaining six species were introduced. Conclusions The distribution patterns of fishes in the Western Ghats are discussed in accordance with the geography of Western Ghats, its climatic conditions and ‘Satpura Hypothesis’. The threat status of fishes found in Western Ghats suggests that at least 41% of fish fauna is threatened by either being VU, EN or CR. Implication of potent conservation measures is necessary to conserve the fish fauna of Western Ghats. 相似文献
64.
人群中存在少量先天性音乐障碍(congenital amusia)个体,表现出音乐感知和表达方面有选择性障碍。本文总结了前人甄别先天性音乐障碍个体的工具,述评了先天性音乐障碍者对音乐加工时的障碍表现,以及先天性音乐障碍者其障碍领域特异性争议,并从行为遗传学和音乐加工脑机制角度,综述了先天性音乐障碍者可能的原因,最后对先天性音乐障碍未来可能的研究方向做了四个方面的展望。 相似文献
65.
Cortical processing associated with orofacial somatosensory function in speech has received limited experimental attention due to the difficulty of providing precise and controlled stimulation. This article introduces a technique for recording somatosensory event-related potentials (ERP) that uses a novel mechanical stimulation method involving skin deformation using a robotic device. Controlled deformation of the facial skin is used to modulate kinesthetic inputs through excitation of cutaneous mechanoreceptors. By combining somatosensory stimulation with electroencephalographic recording, somatosensory evoked responses can be successfully measured at the level of the cortex. Somatosensory stimulation can be combined with the stimulation of other sensory modalities to assess multisensory interactions. For speech, orofacial stimulation is combined with speech sound stimulation to assess the contribution of multi-sensory processing including the effects of timing differences. The ability to precisely control orofacial somatosensory stimulation during speech perception and speech production with ERP recording is an important tool that provides new insight into the neural organization and neural representations for speech. 相似文献
66.
In response to a recent hypothesis that the neuropeptide oxytocin might be involved in human pathogen avoidance mechanisms, we report the results of a study in which we investigate the effect of intranasal oxytocin on two behaviors serving as proxies for pathogen detection. Participants received either oxytocin or a placebo and were asked to evaluate (1) the health of Caucasian male computer-generated pictures that varied in facial redness (an indicator of hemoglobin perfusion) and (2) a series of pictures depicting disgusting scenarios. Men, but not women, evaluated all faces, regardless of color, as less healthy when given oxytocin compared to a placebo. Women, on the other hand, expressed decreased disgust when given oxytocin compared to a placebo. These results suggest that intranasal oxytocin administration does not facilitate pathogen detection based on visual cues, but instead reveal clear sex differences in the perception of health and sickness cues. 相似文献
67.
Donna L. Peppin Peter Z. Ful Janet C. Lynn Anne L. Mottek‐Lucas Carolyn Hull Sieg 《Restoration Ecology》2010,18(Z1):113-124
Increases in revegetation activities have created a large demand for locally adapted native plant materials (NPM) in the southwestern United States. Currently, there is a minimal supply of local genotypes to meet this demand. We investigated the potential for the initiation of a native plant market in the southern Colorado Plateau. Through a literature search, interviews, and site visits, we identified existing native plant markets outside of the region as useful models to help initiate a regional market. We used web‐based surveys to identify and analyze current and future NPM needs and concerns. Survey results indicate that management policy strongly drives decisions regarding the use and purchase of NPM. From a demand perspective , lack of availability and cost of NPM has kept purchasing minimal, despite policy changes favoring the use of natives. For suppliers, further development of NPM is limited by inconsistent and unreliable demand and lack of production knowledge. The knowledge and tools necessary to initiate an NPM market are available, but inadequate funding sources and insufficient information sharing hinder its development. Communication among producers, land managers, buyers, and researchers, as well as partnerships with local growers, appear to be vital to initiating a functional market. 相似文献
68.
This work will characterize risk acceptance in China, based on the psychometric paradigm, and explore the determining factors that influence the risk acceptable level to the Chinese public. For this purpose, a survey was conducted including 12 hazards, 10 risk attributes (including risk acceptance), and demographic variables. First, the research attempted to explore Nanjing citizens’ average risk acceptable level for 12 hazards in China. Second, intercorrelation analysis and factor analysis of nine risk attributes were performed to obtain the suitable risk perception factors as independent variables. Three risk perception models of acceptance were constructed, which were named “Environmental risk model,” “Daily risk model,” and “Technical risk model,” that explained 59.0–69.6% of variance separately. In general, the variables of Knowledge, Benefit, and Trust were found to be significant in all models, implying that these variables are the main determining factors. However, in the environmental risk model, the variable of effect was also significant, which means the determining factors would change for different types of hazards. These results could help the Chinese government to improve the communication of risks with the public and make effective mitigation policies to improve people's rational judgment on the acceptability of risks. 相似文献
69.
70.
Marie-Jeanne Holveck Claire Doutrelant Romain Guerreiro Philippe Perret Doris Gomez Arnaud Grégoire 《Biology letters》2010,6(4):453-457
Eggshell colouration is thought to function as a female-specific secondary sexual trait. While tests of this idea are rapidly accumulating in cavity-nesting birds, some fundamental underlying assumptions remain rarely investigated: namely, can males see eggshell coloration and perceive colour differences between the eggs of different females? We tested these two key assumptions in a natural population of blue tits (Cyanistes caeruleus). Using transponders, we tracked male nest visits and found that all males visited their nest-boxes while eggs were present and often visually accessible. Interestingly, some males also visited neighbouring nests. We then tested whether birds could detect eggshell coloration using models of avian colour vision; models were performed with and without limitations on visual performance owing to dim light. Both models found that differences in eggshell brightness were often easier to discriminate than differences in colour; there was more contrast in white eggshell background between clutches than within and its contrast against nest background was repeatable within clutches, suggesting these features could act as signals. Yet, the detectability of these contrasts depended entirely on model assumptions of visual limitations. Consequently, we need a better understanding of underlying visual mechanisms in dim-light environments and behavioural discrimination experiments before confirming the signalling potential of eggshell coloration. 相似文献