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21.
In seeking to determine whether climate change mitigation strategies are effective, researchers and policy-makers typically use energy consumption as an indicator. UK government data show that energy use amongst the public is rising, despite measures to encourage energy conservation. Yet, research to date has not explicitly asked which actions the public are taking with the express intention of mitigating climate change. Using Stern's classification of impact-oriented and intent-oriented behaviour research, the research described in this paper examines both actions taken ‘out of concern for climate change’ and energy conservation practices amongst the UK public. The findings show a clear divergence between actions prescribed by policy-makers (i.e. energy conservation) and those taken by the public to mitigate climate change (e.g., recycling). Furthermore, those who take action to conserve energy generally do so for reasons unconnected to the environment (e.g., to save money). Regression analyses highlight the distinct determinants of these two behavioural categories. These findings imply that surveys using energy reduction as an indicator of public response to climate change falsely assume that these can be equated; consequently, they will provide a distorted picture of behavioural response. Possible reasons for the asymmetry of intentions and impacts, and policy implications, are discussed.  相似文献   
22.
The advances in ultrasound technology have made it possible to identify fetal structural abnormalities and genetic syndromes in the first trimester. First trimester prenatal diagnosis of fetal central nervous system, renal, gastrointestinal, cardiac, and skeletal abnormalities is reviewed. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   
23.
A multi‐scale soil moisture monitoring strategy for California was designed to inform water resource management. The proposed workflow classifies soil moisture response units (SMRUs) using publicly available datasets that represent soil, vegetation, climate, and hydrology variables, which control soil water storage. The SMRUs were classified, using principal component analysis and unsupervised K‐means clustering within a geographic information system, and validated, using summary statistics derived from measured soil moisture time series. Validation stations, located in the Sierra Nevada, include transect of sites that cross the rain‐to‐snow transition and a cluster of sites located at similar elevations in a snow‐dominated watershed. The SMRUs capture unique responses to varying climate conditions characterized by statistical measures of central tendency, dispersion, and extremes. A topographic position index and landform classification is the final step in the workflow to guide the optimal placement of soil moisture sensors at the local‐scale. The proposed workflow is highly flexible and can be implemented over a range of spatial scales and input datasets can be customized. Our approach captures a range of soil moisture responses to climate across California and can be used to design and optimize soil moisture monitoring strategies to support runoff forecasts for water supply management or to assess landscape conditions for forest and rangeland management.  相似文献   
24.
It has been previously reported that a low or absent maternal serum unconjugated estriol (uE3) level is associated with placental steroid sulfatase (STS) deficiency. Here we report a correlation between patients who present with a very low or absent maternal serum uE3 and a deletion of the STS gene as assessed by fluorescence in situ hybridization (FISH). We studied nine prenatal cases that presented to the clinical laboratory with an abnormal triple screen, specifically low or absent maternal serum uE3 and a 46,XY karyotype. FISH analysis showed complete deletion of a probe containing the STS gene in six cases and one case had a partial deletion (reduced but not absent signal). The remaining two cases were not deleted for the STS probe. All mothers tested whose fetus showed a deletion were shown to be STS deletion carriers using FISH. Biochemical analysis was performed on 7/9 prenatal specimens. All fetuses deleted for the STS probe were also found to be deficient for STS by biochemical analysis of cultured amniotic fluid (5/5). Of the two fetuses not deleted for the STS probe, one was deficient for STS activity, while the other had a normal result. The abnormal result of enzyme deficiency by biochemical analysis in a non-deletion case likely represents a mutation in the STS gene, not detectable by this FISH assay. Postnatal FISH confirmation of the STS deletion was performed in 1/7 cases. Clinical follow-up was available for 4/9 cases following birth. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   
25.
An analytical account of the history and aspirations of the Alex Wilson Community Garden in Toronto provides an ideal opportunity to examine the connections between two typically distinct enterprises: ecological restoration and community gardening. These are both important contemporary ecological movements, but are rarely combined in a single project that demonstrates the principles of sustainable land use and community planning. The garden is named in memory of Alex Wilson, a landscape designer, community activist and writer who worked and lived in Toronto, Canada. During his life, Wilson established a community garden which was eventually replaced by conventional urban development. After his death in 1993, friends and colleagues decided to honour his memory by establishing a permanent community garden in his name. The Alex Wilson Community Garden opened to the public in June 1998. The case-study explores how the garden reflects Wilson's work by linking community gardening and ecological restoration. These features are unified in Wilson's work as a means of nurturing relationships between people, communities and the landscape—relationships that are social, economic and ecological. In his book,The Culture of Nature: North American landscape from Disney to the Exxon Valdez (1991), Wilson argues that “we must build landscapes that heal and empower, that make intelligible our relations with each other and the natural world”. The Alex Wilson Community Garden illustrates in a practical manner the principles espoused by Wilson through its design, planning and functioning. The case-study reports on the innovative approach to landscape design taken in the garden, which reconstructs the natural and cultural history of southern Ontario, featuring lake-shore, agricultural and woodland sections. The garden has been planted exclusively with native plant species, and is expected to have a positive impact on local biodiversity. The planning process which led up to the design of the garden was participatory in nature, encompassing friends and colleagues of Alex Wilson, local residents and city planning officials, and made use of a number of planning tools not usually applied in an urban setting, including the granting of a conservation easement. The garden also addresses emerging issues associated with globalisation and large cities by providing food production opportunities for local residents, including a low-income housing complex and a nearby drop-in centre. Ecological monitoring and assessment of the naturalised area will be carried out by local residents.  相似文献   
26.
This study examines planning process influences on plan sustainability scores for 46 township plans in Central Ohio, in the Midwestern Region of the United States. Townships face many similar development challenges as exurban communities along with cultures and economies which straddle urban and rural perspectives. The empirical analysis shows that participation breadth is positively related to sustainability scores, while the use of the sustainability concept in the planning process is negatively related to sustainability scores. Based on the findings, we suggest that communities preparing a comprehensive plan should encourage participation by a variety of groups in the planning process. Future research should examine the manner in which the sustainability concept is incorporated into the planning process to better assess its influence.  相似文献   
27.
Planetary Stewardship in an Urbanizing World: Beyond City Limits   总被引:1,自引:0,他引:1  
Cities are rapidly increasing in importance as a major factor shaping the Earth system, and therefore, must take corresponding responsibility. With currently over half the world’s population, cities are supported by resources originating from primarily rural regions often located around the world far distant from the urban loci of use. The sustainability of a city can no longer be considered in isolation from the sustainability of human and natural resources it uses from proximal or distant regions, or the combined resource use and impacts of cities globally. The world’s multiple and complex environmental and social challenges require interconnected solutions and coordinated governance approaches to planetary stewardship. We suggest that a key component of planetary stewardship is a global system of cities that develop sustainable processes and policies in concert with its non-urban areas. The potential for cities to cooperate as a system and with rural connectivity could increase their capacity to effect change and foster stewardship at the planetary scale and also increase their resource security.  相似文献   
28.
Thyroid hormones, which influence body metabolism and development, could be affected by persistent organic pollutants. We sought to examine the relationship between polybrominated biphenyls (PBBs) and polychlorinated biphenyls (PCBs) and thyroid disease. We employed incidence density sampling to perform a nested case control analysis of the Michigan Long-Term PBB Cohort. Cohort members (n = 3333) were exposed to PBBs through contaminated cattle feed in 1973-1974 and to PCBs through daily life. Those with detectable serum PBB and PCB concentrations at enrollment were categorized into tertiles of PBB and PCB exposure. Case-patients were cohort members answering “Yes” to “Has a healthcare provider ever told you that you had a thyroid problem?” during follow-up interviews; control-patients were cohort members answering “No”. We used odds ratios (OR) with 95% confidence intervals (CI) to compare odds of thyroid disease by PBB and PCB exposure and by various risk factors. Total cumulative thyroid disease incidence after 33 years was 13.9% among women and 2.6% among men. After adjusting for body mass index, we found no statistically significant differences in odds of any type of thyroid disease among women or men with elevated PBB or PCB exposure. Compared to control-patients, women with thyroid disease had increased odds of being overweight/obese (OR = 2.82, 95% CI: 1.94-4.11) and developing infertility (OR = 1.71, 95% CI: 1.08-2.69), diabetes (OR = 1.61, 95% CI: 1.04-2.51), or arthritis (OR = 1.71, 95% CI: 1.18-2.50) during follow-up. Additional research should explore potential associations between PBBs/PCBs and thyroid disease among children exposed in utero.  相似文献   
29.
An association is described between women with lupus anticoagulant and abnormal prenatal serum screening results. Three cases of positive second-trimester serum screening for Down syndrome, with karyotypically normal fetuses, in women demonstrated to have lupus anticoagulant are presented. Serum screening positivity was principally due to a disproportionately elevated maternal serum human chorionic gonadotrophin (hCG) level. In each case, early, severe intrauterine growth restriction was documented, with only one fetus surviving the neonatal period. As maternal lupus anticoagulant may have a profoundly adverse effect on the course of pregnancy, we suggest that an elevated hCG level on prenatal screening prompt consideration of maternal lupus anticoagulant testing if ultrasonography demonstrates an otherwise normal singleton gestation and the fetal karyotype is normal.  相似文献   
30.
The incidence and severity of visible foliar ozone injury on black cherry (Prunus serotina) seedlings and saplings and tall milkweed (Asclepias exaltata) plants in Great Smoky Mountains National Park (GRSM) were determined by surveys along selected trails conducted during late summer 1992. The incidence (% injured plants) of ozone injury on black cherry was 47% and the percent injured leaves/injured plant and average leaf area injured were 43 and 6%, respectively. Maximum severity (avg. leaf area of the most severely injured leaf) was 12%. Black cherry seedlings and saplings exhibiting ozone injury were taller than non-injured plants. When insect feeding was present, it occurred 96% of the time on plants with ozone injury. Significantly more injury (p=0.007) on black cherry (% injured leaves/injured black cherry) occurred in the NW section of GRSM compared with the other Park sections. Regression analyses showed no relationships in ozone injury with respect to aspect, slope or elevation. Tall milkweed was evaluated twice during August for ozone injury. The incidence (% injured plants) of ozone injury was 74 and 79% for the first and second survey, respectively. The percentage of injured leaves per plant from the first to second survey was 63 to 79%, respectively. Tall milkweeds showing ozone injury were taller than the non-injured plants. The percentage of insect-damaged plants was 50% among plants without ozone injury and 60% among ozone-injured plants. Non-injured tall milkweed had fewer flowers and/or pods than the injured plants. Mean leaf area injured increased over time, and mean maximum leaf area injured increased from 8 to 11% during the same period. Regression analyses showed no differences in ozone injury regarding aspect, slope or elevation. Our findings indicate that ozone injury is widespread throughout the Park on sensitive vegetation.  相似文献   
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