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41.
Many lupine species (Genus Lupinus) contain toxic compounds, although the amount of these substances varies by the plant part and species. This investigation described the epidemiology of 138 lupine exposures reported to Texas poison centers during 1998–2005. Almost 88% of the lupine exposure calls occurred in March and April, and 90% of the calls came from the central portions of the state. Sixty-one percent of the calls involved female patients, and 91% of the patients were age <6 years. The lupine exposure occurred at the patient's own residence in 79% of the cases. Of the reported lupine exposures, 93% were handled outside of health care facilities, and, of those cases with a known medical outcome, few moderate or major effects, and no deaths, were reported. The most frequently noted clinical effect among cases during 2000–2005 was vomiting, affecting 8% of the cases. In conclusion, most reported lupine exposures in Texas came from the central parts of the state, occurred in spring, and involved young children. Typical reported lupine exposures in Texas were not likely to have adverse outcomes.  相似文献   
42.
The purpose of this study was to describe a large number of lionfish envenomations reported to poison control centers. Cases were lionfish envenomations reported to Texas poison control centers during 1998–2006. The distribution of cases was determined for selected parameters. A total of 188 cases were identified. Of the cases with a known location of envenomation, 94% involved the finger or hand. The patient was male in 72% of the cases, and the mean age was 32 years (range 4–65 years). The most frequently reported adverse clinical effects were dermal pain (89%) and a puncture or wound (66%). The most commonly reported treatments were immersion in hot water (84%) and tetanus antitoxin/status (48%). Patients with lionfish envenomations reported to Texas poison control centers were most often adults and males. The reported adverse clinical effects were typical of lionfish envenomations, and the treatments were generally consistent with the recommended guidelines.  相似文献   
43.

Background

Few suitable and standardized test methods are currently available to test the effects of genetically modified plants (GMP) on non-target organisms. To fill this gap and improve ecotoxicological testing for GMP, we developed a new soil ecotoxicological test method using sciarid larvae as test organisms.

Results

Bradysia impatiens was identified as a candidate species. Species of the genus Bradysia occur in high numbers in European agroecosystems and B. impatiens can be reared in the laboratory in continuous culture. A functional basic test design was successfully developed. Newly hatched larvae were used as the initial life stage to cover most of the life cycle of the species during the test. Azadirachtin was identified as a suitable reference substance. In several tests, the effects of this substance on development time and emergence rate varied for different temperatures and test substrates. The toxicity was higher at 25 °C compared to 20 °C and in tropical artificial soil compared to coconut fiber substrate.

Conclusions and outlook

Results suggest that the developed test system is suitable to enter a full standardization process, e.g., via the Organisation for Economic Co-operation and Development. Such a standardization would not only assist the risk assessment of GMP, but could include other stressors such as systemic pesticides or veterinary pharmaceuticals reaching the soil, e.g., via spreading manure. The use of sciarid flies as test organisms supports recommendations of EFSA, which stressed the ecological role of flies and encouraged including Diptera into test batteries.
  相似文献   
44.
The distribution of surface water affects herbivore-vegetation interactions in arid and semi-arid regions. Limited access to surface water typically results in the emergence of vegetation gradients around natural and artificial water sources. In particular, African elephants can create large-scale gradients of woody vegetation. Understanding the dynamics of these gradients is of particular importance for the conservation of other, less mobile herbivores that depend on woody vegetation in areas close to water. While rainfall is known to be a key determinant of herbivore-vegetation interactions in dry areas, we only have limited understanding on how it impacts woody vegetation gradients around waterholes. To address this problem, we developed a deterministic simulation model that describes the interplay of rainfall, elephants and woody vegetation in the vicinity of waterholes. The model is based on elephant telemetry data and the ecological conditions in Etosha National Park (ENP), Namibia. We found that decreasing amounts of rainfall led to an increased degradation of woody vegetation, which was particularly severe in areas close to water. Based on this result we conclude that low rainfall was an important driver of recently observed patterns of vegetation degradation in ENP. More generally, rainfall appears to be a key factor that determines elephant-vegetation interactions and thus dynamics of woody vegetation gradients around waterholes. Using long-term rainfall data from ENP, we also demonstrate that an increase in the number of water sources during periods of low rainfall can mitigate the destructive impact of elephants in areas close to water. However, more research is required to assess the sustainability and effectiveness of rainfall-adapted strategies of artificial water provisioning in more detail. In particular it is important to investigate potential effects on elephant population dynamics.  相似文献   
45.
Mathematical tools are needed to screen out sites where Joule–Thomson cooling is a prohibitive factor for CO2 geo-sequestration and to design approaches to mitigate the effect. In this paper, a simple analytical solution is developed by invoking steady-state flow and constant thermophysical properties. The analytical solution allows fast evaluation of spatiotemporal temperature fields, resulting from constant-rate CO2 injection. The applicability of the analytical solution is demonstrated by comparison with non-isothermal simulation results from the reservoir simulator TOUGH2. Analysis confirms that for an injection rate of 3 kg s?1 (0.1 MT yr?1) into moderately warm (>40 °C) and permeable formations (>10?14 m2 (10 mD)), JTC is unlikely to be a problem for initial reservoir pressures as low as 2 MPa (290 psi).  相似文献   
46.
Armstrong, William H., Mathias J. Collins, and Noah P. Snyder, 2012. Increased Frequency of Low‐Magnitude Floods in New England. Journal of the American Water Resources Association (JAWRA) 48(2): 306‐320. DOI: 10.1111/j.1752‐1688.2011.00613.x Abstract: Recent studies document increasing precipitation and streamflow in the northeastern United States throughout the 20th and early 21st Centuries. Annual peak discharges have increased over this period on many New England rivers with dominantly natural streamflow – especially for smaller, more frequent floods. To better investigate high‐frequency floods (<5‐year recurrence interval), we analyze the partial duration flood series for 23 New England rivers selected for minimal human impact. The study rivers have continuous records through 2006 and an average period of record of 71 years. Twenty‐two of the 23 rivers show increasing trends in peaks over threshold per water year (POT/WY) – a direct measure of flood frequency – using the Mann‐Kendall trend test. Ten of these trends had p < 0.1. Seventeen rivers show positive trends in flood magnitude, six of which had p < 0.1. We also investigate a potential hydroclimatic shift in the region around 1970. Twenty‐two of the 23 rivers show increased POT/WY in the post‐1970 period when comparing pre‐ and post‐1970 records using the Wilcoxon rank‐sum test. More than half of these increases have p < 0.1, indicating a shift in flow regime toward more frequent flooding. Region wide, we found a median increase of one flood per year for the post‐1970 period. Because frequent floods are important channel‐forming flows, these results have implications for channel and floodplain morphology, aquatic habitat, and restoration.  相似文献   
47.
Haematological (WBC, RBC, Hgb and Hct) and genotoxicity (MNT) parameters, hepatic enzymatic activities (GST, GPx and GR), and a histopathological evaluation of liver, kidneys and gonads were assessed as general biomarkers of metal pollution in the shrew Crocidura russula inhabiting a pyrite mining area. Specimens exposed to metals presented a few significant alterations when compared with reference animals: GST activity decreased; micronuclei increased; and evident liver alterations related to metal exposure were observed. On the basis of all the parameters studied, age was an important factor that partly explained the observed variation, whereas sex was the least important factor. Significant correlations were also found between heavy metal concentrations and biomarkers evaluated, demonstrating the great influence of these metals in the metabolic alterations. To the best of our knowledge, these data constitute the first measurements of a battery of biomarkers in shrews from a mine site and are among the few available for insectivorous mammals.  相似文献   
48.
49.
ABSTRACT

African countries are among the prime destinations of electronic waste (e-waste) also called Waste of Electrical and Electronic Equipment (WEEE), and have been challenged with the management of its environmental and health impacts. This paper was carried out to understand the e-waste sector and policy responses in selected African countries. Data for the study were generated from sources; such as policy documents, legislations and literature. Findings show that the import of WEEE is on rising in Africa while landfill and incineration continued to be widely used handling approaches. Countries studied lack WEEE specific national policies and stringent policy instruments to enforce proper collection and recycling systems. Despite the start-ups in emerging recycling operations, a major gap is that informal e-waste actors dominate the e-waste chain from collection to material extraction and refurbish activities through rudimentary tools that cannot detect toxic elements. Tackling the problem demands integrated multi-actor interventions with multiple stakeholders to reduce WEEE inflow on one hand, and ramping up safe recycling capacity on the other hand.  相似文献   
50.
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