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91.
We developed a stochastic model for quantitative risk assessment for the Schistosoma mansoni (SM) parasite, which causes an endemic disease of public concern. The model provides answers in a useful format for public health decisions, uses data and expert opinion, and can be applied to any landscape where the snail Biomphalaria glabrata is the main intermediate host (South and Central America, the Caribbean, and Africa). It incorporates several realistic and case‐specific features: stage‐structured parasite populations, periodic praziquantel (PZQ) drug treatment for humans, density dependence, extreme events (prolonged rainfall), site‐specific sanitation quality, environmental stochasticity, monthly rainfall variation, uncertainty in parameters, and spatial dynamics. We parameterize the model through a real‐world application in the district of Porto de Galinhas (PG), one of the main touristic destinations in Brazil, where previous studies identified four parasite populations within the metapopulation. The results provide a good approximation of the dynamics of the system and are in agreement with our field observations, i.e., the lack of basic infrastructure (sanitation level and health programs) makes PG a suitable habitat for the persistence and growth of a parasite metapopulation. We quantify the risk of SM metapopulation explosion and quasi‐extinction and the time to metapopulation explosion and quasi‐extinction. We evaluate the sensitivity of the results under varying scenarios of future periodic PZQ treatment (based on the Brazilian Ministry of Health's plan) and sanitation quality. We conclude that the plan might be useful to slow SM metapopulation growth but not to control it. Additional investments in better sanitation are necessary.  相似文献   
92.
Estimates of adult mortality in countries with limited vital registration (e.g., sub-Saharan Africa) are often derived from information about the survival of a respondent’s siblings. We evaluated the completeness and accuracy of such data through a record linkage study conducted in Bandafassi, located in southeastern Senegal. We linked at the individual level retrospective siblings’ survival histories (SSH) reported by female respondents (n = 268) to prospective mortality data and genealogies collected through a health and demographic surveillance system (HDSS). Respondents often reported inaccurate lists of siblings. Additions to these lists were uncommon, but omissions were frequent: respondents omitted 3.8 % of their live sisters, 9.1 % of their deceased sisters, and 16.6 % of their sisters who had migrated out of the DSS area. Respondents underestimated the age at death of the siblings they reported during the interview, particularly among siblings who had died at older ages (≥45 years). Restricting SSH data to person-years and events having occurred during a recent reference period reduced list errors but not age and date errors. Overall, SSH data led to a 20 % underestimate of 45 q 15 relative to HDSS data. Our study suggests new quality improvement strategies for SSH data and demonstrates the potential use of HDSS data for the validation of “unconventional” demographic techniques.  相似文献   
93.
Lawns are considered monocultures and lesser contributors to sustainability than diverse nature but are still a dominating green area feature and an important cultural phenomenon in cities. Lawns have esthetical values, provide playground, are potential habitat for species, contribute to carbon sequestration and water infiltration, but also increase pesticides, fertilization, are monocultures and costly to manage at the same time. To evaluate the potential impact of lawns, whether positive or negative, it is of interest to estimate the total lawn cover in cities and its change over time. This is not a straightforward process, e.g., because many lawns are small and covered by trees. In this study we review the existing literature of lawn cover in cities and the different methodologies used for cover estimation. We found both pros and cons with NDVI and LiDAR data as well as manually interpreted aerial photos. The total cover of lawns in three case study cities was estimated to 22.5%. By extrapolating these percentages to all Swedish cities lawn cover was estimated to 2589 km2 (0.6% of the terrestrial surface). The approximated total municipal management cost of lawns in all Swedish cities was 910,000,000 USD/ year. During 50 years lawn area almost doubled in relative cover and 56% of them were continuously managed. Since lawns constitute large parts of the urban greenery and are costly to manage it is highly relevant to consider their social, ecological and cultural value compared to alternatives, e.g., meadows with less intensive management.  相似文献   
94.
Mainstream conceptualizations of ‘ethical consumption’ equate the notion with conscious, individual, market‐mediated choices motivated by ethical or political aims that transcend ordinary concerns. Drawing on recent sociology and anthropology of consumption literature on the links between ordinary ethics and ethical consumption, this article discusses some of the limitations of this conceptualization. Using data from 32 focus groups conducted in Chile and Brazil, we propose a conceptualization of ethical consumption that does not centre on individual, market‐mediated choices but understands it at the level of practical outcomes, which we refer to as different forms of ‘ethical living’. To do that, we argue, we need to depart from the deontological understanding of ethics that underpins mainstream approaches to ethical consumption and adopt a more consequentialist view focusing on ethical outcomes. We develop these points through describing one particular ordinary moral regime that seemed to be predominant in participants’ accounts of ethics and consumption in both Chile and Brazil: one that links consumption and ethics through care. We show that the moral regime of care leads to ‘ethical outcomes’, such as energy saving or limiting overconsumption, yet contrary to the mainstream view of ethical consumption emphasizing politicized choice expressed through markets, these result from following ordinary ethics, often through routines of practices.  相似文献   
95.
96.
Homelessness among older people in Canada is both a growing concern, and an emerging field of study. This article reports thematic results of qualitative interviews with 40 people aged 46 to 75, carried out as part of a mixed-methods study of older people who are homeless in Montreal, Quebec, Canada. Our participants included people with histories of homelessness (= 14) and persons new to homelessness in later life (= 26). Interviews focused on experiences at the intersections of aging and homelessness including social relationships, the challenges of living on the streets and in shelters in later life, and the future. This article outlines the 5 main themes that capture the experience of homelessness for our participants: age exacerbates worries; exclusion and isolation; managing significant challenges; shifting needs and realities; and resilience, strength, and hope. Together, these findings underscore the need for specific programs geared to the unique needs of older people who are homeless.  相似文献   
97.
We propose a new procedure for the multinomial selection problem to solve a real problem of any modern Air Force: the elaboration of better air-to-air tactics for Beyond Visual Range air-to-air combat that maximize its aircraft survival probability H(θ, ω), as well as enemy aircraft downing probability G(θ, ω). In this study, using a low-resolution simulator with generic parameters for the aircraft and missiles, we could increase an average success rate of 16.69% and 16.23% for H(θ, ω) and G(θ, ω), respectively, to an average success rate of 76.85% and 79.30%. We can assure with low probability of being wrong that the selected tactic has greater probability of yielding greater success rates in both H(θ, ω) and G(θ, ω) than any simulated tactic.  相似文献   
98.
Focusing on the Spanish case, this article addresses two fundamental questions: why were many unionized workers sceptical about state intervention in labour issues throughout the nineteenth century, and why did this attitude begin to change from the 1860s onwards? Its main thesis is that workers’ attitudes derived ultimately from different historical notions of ‘society’ that shaped their perceptions and experiences of labour relations and their attitude toward the role of the state. Thus, a notion of society as an aggregation of individuals shaped unionized Spanish workers’ hostility toward state intervention since the creation of the first unions in the 1840s. From the 1860s onward, a new conception of collective relations, namely ‘the social’, began to transform some workers’ expectations of the role of the state in labour conflicts. The main factor that explains this change, it is argued, lies in the relationship between the workers’ imaginary, their actions, and their expectations about these actions.  相似文献   
99.
The study of deprivation, as a social indicator, is basic in the design and development of public policies because it allows decision makers to identify and analyse needy areas in order to improve their citizens’ well-being. The methodological approach proposed for the development of a new deprivation index is based on the Causal Theory whose conceptual model is analysed using Structural Equations. The domains selected for the deprivation index are: education, employment, income, housing, infrastructures and health. A structural equation model based on variance is the exploratory method used to obtain the indices pertaining to the above mentioned areas; the results obtained are seen to be quite reliable. There is a positive connection between the areas of education, employment and income while the relations between infrastructures and health are found to be negative. The results can be projected at a local level and show basic territorial deficiencies. The spatial units studied are the Andalusian (south of Spain) municipalities (770). The spatial projection of the indices obtained for the domains of deprivation highlights the existence of geographical areas which could be a potential target for public action.  相似文献   
100.
This study aimed to analyze the effects of caloric restriction on aged femoral articular cartilage of Wistar rats. Three groups of eight animals each were considered: young (YC) and old (OC) control groups fed with a normal diet and old caloric restriction group (OCR) composed of 18-month-old animals fed with a 31% less caloric diet from 6-months of age. Articular cartilage was studied through morphometry and immunohistochemistry. Body mass was 12% less in the OCR group than in the OC group. The articular cartilage from OC rats show thinner medial condyles, fewer chondrocytes, smaller chondrocytes nuclear volume and, in both condyles, a predominance of collagen type II and less collagen density compared to both YC and OCR groups (p?p?相似文献   
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