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1.
Protected areas in developing countries play a vital role in promoting the ideal of sustainable development.But 'people-park'conflicts are commonplace,threatening the future of these areas and the long term well-being of local communities. Surprisingly, little attention has been given to applying lessons learned in conflict studies to people-parkconflicts. In contrast to traditional adversarialresponses, negotiated approaches offer considerable potential for transforming people-park conflicts into mutually beneficial relationships.Experiencesin the Richtersveldregion of South Africa demonstrate the cardinal role negotiation can play in addressing key issues underlying people-park conflicts.  相似文献   
2.
Mosaicism for the Wolf-Hirschhorn syndrome, del(4)(p16), is extremely rare and has not been reported in association with a numerical chromosome abnormality. We report the prenatal diagnosis of mosaic del(4)(p16) and non-mosaic trisomy 21 in a 16-week female fetus. The pregnancy ended in spontaneous abortion at 34 weeks secondary to fetal demise. The fetus had features of both 4p – and trisomy 21.  相似文献   
3.
In 40 pregnancies at risk for the Hurler syndrome 13 affected fetuses were detected by the demonstration of an α-L -iduronidase deficiency and an increased level of 35S-sulphate incorporation. The diagnoses were confirmed by the analysis of fetal tissues and/or cultured fetal skin fibroblasts. Microassays for α-L -iduronidase, using phenyl α-L -iduronide and more recently 4–methyl-umbelliferyl α-L -iduronide, enabled a reliable diagnosis to be made within 15 to 18 days after amniocentesis. 35S-sulphate incorporation has been a valuable adjunct in cases with a low (heterozygote) enzyme activity.  相似文献   
4.
Ammonia emission from grassland and livestock production systems in the UK   总被引:3,自引:0,他引:3  
Emissions of ammonia were measured from livestock excreta and fertilisers applied to grass swards, from grazed paddocks, from decomposing grass herbage and from an animal house containing dairy cows. Emissions from urine, dung, slurry and fertilisers were determined using a system of wind tunnels with each tunnel covering an area of 1 m(2). Emissions from grazed swards were determined using a micrometeorological mass balance method. From the results of these measurements, together with other published information, an inventory for ammonia emissions has been calculated for grassland and livestock production systems over the UK as a whole. It is estimated that emissions from grassland and cattle and sheep production amount to about 230 kt NH(3)-N annually, while emissions from pig and poultry production amount to about 40 kt and 80 kt NH(3)-N, respectively.  相似文献   
5.
Certain widely used wind rose programs and air dispersion models use an overly simple data-transfer algorithm that induces a directional bias in their output products. The purpose of this paper is to provide a revised algorithm that corrects the directional bias that occurs from the aliasing that occurs when the sector widths used to report wind direction data are on the same order of magnitude, but not equal, to the sector widths used in the wind direction summaries. The directional bias issue arises when output products in 16 direction sectors (22.5 degrees each) are produced from wind direction data reported in terms of 36 sectors (10 degrees each). The result directional bias affects the results of simulations of air and surface concentrations using widely applied air dispersion models. Datasets or models with the directional bias discussed here give consistent positive biases (approximately 30%) for cardinal direction sectors (north, south, east, and west) and consistent negative biases for all of the other sectors (around -10%). Data summary and air dispersion programs providing outputs in direction sectors that do not match the observational sectors need to be checked for this bias. A revised data-transfer algorithm is provided that corrects the directional bias that can occur in transferring wind direction data between different sector widths.  相似文献   
6.
The suddenness and scale of the 26 December 2004 tsunami and the challenges posed to affected communities highlighted the benefits of their members having a capacity to confront and adapt to the consequences of such a disaster. Research into adaptive capacity or resilience has been conducted almost exclusively with Western populations. This paper describes an exploratory study of the potential of a measure of collective efficacy developed for Western populations to predict the capacity of members of a collective society, Thai citizens affected by the 2004 tsunami, to confront effectively the recovery demands associated with this disaster. Following a demonstration that this measure could predict adaptive capacity, the role of religious affiliation, ethnicity and place of residence in sustaining collective efficacy is discussed. The implications of the findings for future research on, and intervention to develop, adaptive capacity among Thai citizens in particular and collectivist societies in general are discussed.  相似文献   
7.
A two-generation reproductive toxicity study of zinc chloride (ZnCl(2)) was conducted in rats. F(o) male and female rats were administered 0.00 (control), 7.50 (low), 15.00 (mid) and 30.00 (high) mg/kg/day of ZnCl(2). Selected F(1) male and female rats were exposed to the same doses received by their parents (F(o)). Exposure of F(0) parental rats to ZnCl(2) showed significant reduction in fertility, viability (days 0 and 4), and the body weight of F(1) pups from the high-dose group but caused no effects on litter size, weaning index, and sex ratio. Similarly, the continued exposure of F(1) parental rats to ZnCl(2) also reduced fertility, liter size, viability (day 0), and the body weight of F(2) pups within the high-dose group but caused no effects on weaning index and sex ratio. Exposure of ZnCl(2) to F(0) and F(1) parental males resulted in a significant reduction in their body weights, and the F(0) and F(1) parental females did not show any significant difference in their body weights compared to their control groups. However, the postpartum dam weights of both F(0) and F(1) female rats were significantly reduced compared to their controls. Exposure of ZnCl(2) to F(o) and F(1) generation parental rats did not produce any significant change of their clinical signs as well as their clinical pathology parameters, except the alkaline phosphotase (ALK) level, which showed an upward trend in both sexes of both generations. Exposure of ZnCl(2) to F(0) rats resulted in a reduction of brain, liver, kidney, spleen and seminal vesicles weights of males and in the spleen and uterus of females. Similarly, exposure of F(1) rats to ZnCl(2) also resulted in reduction of brain, liver, kidney, adrenal, spleen, prostate and seminal vesicles weights of males and in spleen and uterus of females. ZnCl(2) exposure resulted in grossly observed gastro-intestianla (GI) tract, lymphoreticular/hematopoietic, and reproductive tract lesions in parental rats in both generations. Reduced body fat was also recorded in F(1) parental rats.  相似文献   
8.
Three different polyvinyl chloride (PVC) pipe types were subjected to de-ionized water exposures over the course of at least 180 days. Water exposed to the pipe was analyzed for organotin speciation and concentration. Organotin concentrations were the highest during the first 1-5 days. The species and concentrations of organotins leached varied by pipe type. Data were normalized by surface area in order to compare laboratory results with results from a residential pipe system. For one pipe type, the lowest non-zero concentrations from the laboratory tests overestimated organotin concentrations in solution when compared with water samples from the same pipe type in a residence. For organotin exposure estimates, a range of 0.1 ng m(-2) to 10 ng m(-2) could be used for mature pipes (e.g. in use for 1 year). These estimates should be refined with more field study, however, due to the high variation in organotin species and concentrations leached as a function of pipe type, accuracy within an order of magnitude may be optimal as, in many instances, the type of pipe installed or buried may be unknown. X-ray absorption spectroscopy (XAS) was used to identify organic and inorganic tin species in reference materials and the PVC samples. Monobutyl tin was identified as the primary organotin species in the pipes. Results from the XAS analyses also indicate that the technique shows promise for distinguishing between inorganic tin and organotins. Furthermore, organotins may be distinguished between mono-, di-, and tri-ligand species using XAS.  相似文献   
9.
A long‐standing “Digital Divide” in data representation exists between the preferred way of data access by the hydrology community and the common way of data archival by earth science data centers. Typically, in hydrology, earth surface features are expressed as discrete spatial objects (e.g., watersheds), and time‐varying data are contained in associated time series. Data in earth science archives, although stored as discrete values (of satellite swath pixels or geographical grids), represent continuous spatial fields, one file per time step. This Divide has been an obstacle, specifically, between the Consortium of Universities for the Advancement of Hydrologic Science, Inc. and NASA earth science data systems. In essence, the way data are archived is conceptually orthogonal to the desired method of access. Our recent work has shown an optimal method of bridging the Divide, by enabling operational access to long‐time series (e.g., 36 years of hourly data) of selected NASA datasets. These time series, which we have termed “data rods,” are pre‐generated or generated on‐the‐fly. This optimal solution was arrived at after extensive investigations of various approaches, including one based on “data curtains.” The on‐the‐fly generation of data rods uses “data cubes,” NASA Giovanni, and parallel processing. The optimal reorganization of NASA earth science data has significantly enhanced the access to and use of the data for the hydrology user community.  相似文献   
10.
Fresh beef cattle (Bos taurus) manure has traditionally been applied to cropland in southern Alberta, but there has been an increase in application of composted manure to cropland in this region. However, the quality of runoff under fresh manure (FM) versus composted manure (CM) has not been investigated. Our objective was to compare runoff quality under increasing rates (0, 13, 42, 83 Mg ha(-1) dry wt.) of FM and CM applied for two consecutive years to a clay loam soil cropped to irrigated barley (Hordeum vulgare L.). We determined total phosphorus (TP), particulate phosphorus (PP), dissolved reactive phosphorus (DRP), total nitrogen (TN), NH4-N, and NO3-N concentrations and loads in runoff after one (1999) and two (2000) applications of FM and CM. We found significantly (P < or = 0.05) higher TP, DRP, and NH4-N concentrations, and higher DRP and TN loads under FM than CM after 2 yr of manure application. The TP loads were also higher under FM than CM at the 83 Mg ha(-1) rate in 2000, and DRP loads were higher for FM than CM at this high rate when averaged over both years. Application rate had a significant effect on TP and DRP concentrations in runoff. In addition, the slope values of the regressions between TP and DRP in runoff versus application rate were considerably higher for FM in 2000 than for FM in 1999, and CM in both 1999 and 2000. Significant positive relationships were found for TP and DRP in runoff versus soil Kelowna-extractable P and soil water-extractable P for FM and CM in 2000, indicating that interaction of runoff with the soil controlled the release of P. Total P and DRP were the variables most affected by the treatments. Overall, our study found that application of CM rather than FM to cropland may lower certain forms of P and N in surface runoff, but this is dependent on the interaction with year, application rate, or both.  相似文献   
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