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31.
Most North Americans are concerned about the environment and feel that responsibility for its protection lies primarily with government; however, no research to date has examined the influence of the government's approach toward environmental regulation on the motivation of individual citizens. According to self-determination theory, social contexts that support one's autonomy should facilitate self-determined motivation and social contexts that thwart autonomy should lead to non self-determined motivation and a sense of apathy or amotivation. In this study (n = 283), we examined the influence of perceptions of the government's approach toward environmental regulation on motivation toward the environment and frequency of self-reported pro-environmental behavior (PEB). Using structural equation modeling, we tested the hypothesis that frequency of PEB is predicted by motivation toward the environment and that motivation is predicted by the extent to which individuals perceive the government to be autonomy-supportive versus controlling in the implementation of environmental policies. The analysis revealed that perception of government autonomy-support contributed positively to autonomous motivation and negatively to amotivation, while perception of government control was positively related to both controlled motivation and amotivation. As predicted, autonomous motivation was positively, and amotivation was negatively, associated with frequency of PEB.  相似文献   
32.
Buzz Sharp 《Disasters》2007,31(S1):S104-S123
In the post-Comprehensive Peace Agreement (CPA) era a greater impact on the unacceptably high prevalence of child malnutrition is more likely to come from additional investment and attention to education, health, hygiene, sanitation and childcare practices than from expanded food aid interventions. The negligible impact of food aid on malnutrition, although most commonly challenged on the quality of needs assessments, is equally attributable to the timing of deliveries, and a dysfunctional distribution system. Comparatively few resources have been allocated to strengthen skills for assessing, analysing and understanding community priorities, local economies, and social safety nets. A more thoughtful allocation of scarce funds could have more impact if a range of alternative responses was considered. Participation in and commitment to a more independent livelihoods analytical forum would improve communication with the new government, local leaders and other partners, as well as providing a platform for reaching consensus on both humanitarian and development planning over the next five years.  相似文献   
33.
New Zealand has over 500 offshore islands. Many consist of relatively pristine wilderness and contain a disproportionately large amount of New Zealand's biological wealth. Increased demand for recreation has increased the pressure to develop these areas. Although the New Zealand public has shown widespread support for the preservation and safeguarding of both wilderness areas and endangered species, economic values attached to the benefits of preservation are not known. Using a telephone survey, we found evidence that the public attaches significant value to the conservation of Little Barrier Island. The results show that these values are influenced by different levels and sources of prior information.  相似文献   
34.
Prenatal diagnosis was requested for a couple with a previous child affected by the peroxisomal disorder D-bifunctional protein deficiency. Prior analysis of the D-bifunctional protein cDNA sequence from the propositus had shown that it was missing 22 bp. This was subsequently attributed to a point mutation in the intron 5 donor site (IVS5+1G>C) of the D-bifunctional protein gene. Consistent with parental consanguinity, the patient was shown to be homozygous for this mutation, which is associated with loss of a Hph 1 restriction site in the genomic sequence. Prenatal testing of the fetus using genomic DNA isolated from uncultured amniocytes indicated that both alleles of the D-bifunctional protein had the IVS5+1G>C substitution. The peroxisomal defect was later confirmed biochemically using cultured amniocytes, which were found to have elevated levels of very long chain fatty acids (VLCFA). This is the first report of prenatal diagnosis of D-bifunctional protein deficiency using molecular analysis of genomic DNA. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   
35.
Though the solid waste management (SWM) system in Phnom Penh city in general has been upgraded since the waste collection service was franchised out to the private sector, the performance of the existing SWM system is still low. Unreliable and irregular collection service still exists. This means that there are shortcomings in the existing SWM system that need correction. This paper is an attempt to identify those shortcomings in order to find ways to improve the existing system. First, the present SWM system is reviewed. Then the system is evaluated to find constraints and shortfalls and finally some appropriate strategies are proposed that may help make SWM in the city more effective and efficient to meet environmentally sound objectives.  相似文献   
36.
INTRODUCTION: The main objective of this paper is to highlight travel patterns of older adults living in the United States as depicted in the 2001 National Household Travel Survey (NHTS). The NHTS is a national data collection program sponsored by the Bureau of Transportation Statistics and the Federal Highway Administration. It is the first national comprehensive household survey of both daily and long-distance travel, allowing for analysis of the full continuum of personal travel by Americans. To better understand the transportation needs of older Americans, it is useful to examine how travel patterns differ across age groups. The intent is to present basic travel characteristics of older adults (age 65+) and allow for comparisons with younger adults (ages 19-64). Travel-related characteristics of older adults in the United States: Results of the 2001 survey showed that older Americans travel extensively and rely on personal vehicles as heavily as their younger counterparts. Older Americans conduct 89% of their travel in personal vehicles. CHARACTERISTICS OF DAILY TRIPS TAKEN BY OLDER ADULTS: Older adults tend to be less mobile in that they take fewer trips, travel shorter distances, and have shorter travel times. This pattern is even more pronounced among older women. They are also more likely to suffer from self-reported medical conditions that further limit their travel. Characteristics of long-distance travel by older adults: Older men and women take long-distance trips at about the same rates and show a strong preference for using personal vehicles. And, while men and women take an equal percentage of their trips by air, older women show a strong preference for bus travel. CONCLUSIONS: Although older Americans travel extensively, they are less mobile than their younger counterparts. This pattern is more pronounced among older women and among those with self-reported medical conditions that affect their ability to travel outside their home. Older women consistently take the least number of trips per day, have the lowest driving rates, travel the shortest distances, and are more likely to report medical conditions that limit their travel. For men and women who have to give up driving, alternative means of transportation becomes a necessity. Yet, use of alternative transportation is relatively low; excluding personal vehicle and walking, all other means of transportation account for about 2% of daily travel. Further, of those with medical conditions that affect their travel, only about 12% use special transportation services such as dial-a-ride.  相似文献   
37.
A 37 year-old woman with a twin pregnancy underwent amniocentesis to exclude fetal chromosome abnormality. The results indicated that both fetuses were mosaics, with 45,X and 46,XX, cell lines. Since it was suspected from the ultrasound scan that the twins were dizygotic, the result was questioned. Fetoscopy and fetal blood sampling were performed and karyotyping the fetal lymphocytes confirmed that one twin was indeed a mosaic, 45,X/ 46,XX, but the other had a normal male chromosome complement. The pregnancy resulted in the birth of a phenotypically normal girl, in whom the 45,X/46,XX mosaicism was confirmed, and a normal boy.  相似文献   
38.
In certain hydrogeological situations, fluid density variations occur because of changes in the solute or colloidal concentration, temperature, and pressure of the groundwater. These include seawater intrusion, high-level radioactive waste disposal, groundwater contamination, and geothermal energy production. When the density of the invading fluid is greater than that of the ambient one, density-driven free convection can lead to transport of heat and solutes over larger spatial scales and significantly shorter time scales than compared with diffusion alone. Beginning with the work of Lord Rayleigh in 1916, thermal and solute instabilities in homogeneous media have been studied in detail for almost a century. Recently, these theoretical and experimental studies have been applied in the study of groundwater phenomena, where the assumptions of homogeneity and isotropy rarely, if ever, apply. The critical role that heterogeneity plays in the onset as well as the growth and/or decay of convective motion is discussed by way of a review of pertinent literature and numerical simulations performed using a variable-density flow and solute transport numerical code. Different styles of heterogeneity are considered and range from continuously "trending" heterogeneity (sinusoidal and stochastic permeability distributions) to discretely fractured geologic media. Results indicate that both the onset of instabilities and their subsequent growth and decay are intimately related to the structure and variance of the permeability field. While disordered heterogeneity tends to dissipate convection through dispersive mixing, an ordered heterogeneity (e.g., sets of vertical fractures) allows instabilities to propagate at modest combinations of fracture aperture and separation distances. Despite a clearer understanding of the processes that control the onset and propagation of instabilities, resultant plume patterns and their migration rates and pathways do not appear amenable to prediction at present. The classical Rayleigh number used to predict the occurrence of instabilities fails, in most cases, when heterogeneous conditions prevail. The incorporation of key characteristics of the heterogeneous permeability field into relevant stability criteria and numerical models remains a challenge for future research.  相似文献   
39.
Characterizing dry weather conditions in urban Municipal Separate Storm Sewer Systems (MS4s), and then prioritizing and addressing problems due to urban pollutants, is a daunting challenge. The size and complexity of most MS4s and the ephemeral nature of many dry weather problems hamper efforts to identify and eliminate pollutant sources, and to track trends in condition. As a result, assessing overall program progress has proven difficult. We describe a hybrid dry weather urban monitoring design from southern California that combines probabilistic and targeted sampling to rigorously identify and prioritize problems and track program progress. Data from probabilistic sites define the urban background and establish tolerance intervals, which identify sites that persistently exceed the overall urban background. Targeted sites focus on locations where nearby activities and/or past history suggest that pollutant levels will be elevated. Embedding targeted monitoring within a probabilistic design enables data from targeted sites to be interpreted in a more meaningful regional context. Data from all sites are also used to construct site- and pollutant-specific control charts. These charts quickly identify instances where a site's behavior significantly changes, compared to its past behavior, suggesting an active source in the upstream drainage area. The hybrid design, and the use of formal statistical tools (tolerance intervals and control charts), permit the program to systematically prioritize problematic sites, compare conditions to the regional urban background, and track trends over time. In addition, the program's design allows several measures of program progress to be defined and thus consistently followed over time. Such hybrid designs can provide substantial advantages compared to more traditional monitoring approaches.  相似文献   
40.
An XeBr excilamp having a peak emission at 283 nm, and microwave UV lamps with peak emissions at 253.7 nm that also generate ozone, have been tested for ability to eradicate high populations of microbial vegetative cells and spores (of bacteria and fungi) artificially added to filter surfaces. The study examined the energy required to completely eradicate large populations on filter surfaces. It was found that both the excilamp and microwave UV lamps were effective at killing large populations on surfaces with killing efficiency dependant on the type of organism, and, whether present in its vegetative or spore forms. The main killing factor is UV radiation following short treatment times. It is considered that for longer irradiation periods that are required to facilitate complete destruction of surface microorganisms, ozone and other oxidising species produced by microwave UV lamps would act to enhance microbial destruction.  相似文献   
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