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91.
92.
Vascular anomalies are rare disorders that encompass a group of lesions characterized by abnormal development of the lymphovascular system. Majority of these anomalies are present at birth and could potentially be detected during the prenatal period on imaging. This allows for early intervention and prompt management to improve outcomes. However, they can be difficult to diagnose, given the rarity and overlapping findings. In this review article, we provide a comprehensive overview of congenital vascular anomalies with a liberal use of images of recent cases at our center emphasizing prenatal imaging findings and the natural history of these conditions. 相似文献
93.
Les W. Stanfield Don A. Jackson 《Journal of the American Water Resources Association》2011,47(2):315-336
Stanfield, Les W. and Don A. Jackson, 2011. Understanding the Factors That Influence Headwater Stream Flows in Response to Storm Events. Journal of the American Water Resources Association (JAWRA) 1‐22. DOI: 10.1111/j.1752‐1688.2010.00518.x Abstract: Headwater drainage features (first‐ to second‐order streams) are the capillaries of the landscape that, among other things, moderate the timing and volumes of water available to the riparian and aquatic ecosystems. How these features respond to summer rainfall is poorly understood. We studied how geology and an index of land use/land cover influenced peak flows following rainfall events in 110 headwater stream sites that were studied over a four‐month period during a drought year. Highest peak flows were observed in the most urbanized catchments and in poorly drained soils, but specific responses were variable depending on both geology and land disturbance. Redundancy analysis indicated that both surficial geology and land disturbance were important factors influencing peak flows under drought conditions. We conclude that responses of these headwater streams to individual storms during drought conditions are unpredictable from data collected using our methods, but increased peak flows were associated with increased urban and agricultural development, but mitigated by surficial geology. These findings demonstrate the challenges to accurately predict flow conditions in headwater streams during periods of extreme weather that concurrently have the greatest potential effect on biota. The combination of these challenges and importance of such events indicates the need to develop new approaches to study and manage these resources. 相似文献
94.
Abstract The German cockroach is the most common pest of urban, low-income housing in the United States and is associated with high pesticide use by residents. Cockroach allergen is implicated in asthma exacerbation and initiation and in the growing social and medical aspects of the disease. A safe and secure home environment is an environmental justice issue, and environmentally sound and effective models of cockroach control are needed in public and low-income multifamily housing. One model that offers potential is the integrated pest management (IPM) peer educator model (IPM Educator) in public housing as a component of IPM. A pre–post-analysis of an IPM Educator pilot programme in Boston public housing was undertaken. Thirty-four moderate- to high-infested units received baseline assessment and three applications of gel baits and IPM treatment by a pest control operator. Before the first pest control application, residents received written notice to prepare their units for treatment, a standard procedure. Before the second and third pest control treatments, an IPM Educator instructed residents in basic pest biology and habits, preparation for treatment, and the role of sanitation in pest control. Results showed a significant improvement in rate of preparation for pest control treatment after the IPM Educator intervention when compared with the preparation rate before the education intervention, and a significant reduction in cockroach populations by the third visit in units that were prepared and had improved sanitation, when compared with unprepared units and unclean units. The IPM peer educator is a promising, low-cost model of educating and engaging residents of urban, low-income, multifamily housing in environmentally sound pest control, thereby giving them some power and control over their living environment. It is also a potential source of professional training and jobs for public housing and other low-income housing residents. 相似文献
95.
Don Huisingh 《生态毒理学报》2003,(4):48-51
清洁生产原则的积极推广,有赖于政府、工业界和“推动组织“(例如金融和教育机构、非政府组织、技术指导人员和咨询人员、工业协会)间有效合作伙伴关系的推动与发展.本文引证了推动组织参与的一些成功行动.迫切希望不同的利益相关者在推动社会向可持续性发展转化中,发挥更积极的作用. 相似文献
96.
Catherine D. Kashork V. Reid Sutton Jill S. Fonda Allen Deborah E. Schmidt Marisa L. Likhite Lorraine Potocki William E. O'Brien Lisa G. Shaffer 《黑龙江环境通报》2002,22(11):1028-1032
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
97.
S. Hallsworth A.J. Dore W.J. Bealey U. Dragosits M. Vieno S. Hellsten Y.S. Tang M.A. Sutton 《Environmental Science & Policy》2010,13(8):671-687
New ‘critical levels’ (CLE) for assessing the effects of atmospheric ammonia on sensitive ecosystems have recently been adopted by the United Nations Economic Commission for Europe (UNECE) of 1 and 3 [2–4] μg NH3 m?3 of ambient air (including water vapour), for different species sensitivities and their associated habitats. Based on these values, we examined how indicator choice affects estimates of stock-at-risk in the European ‘Natura 2000’ network.We applied an atmospheric model, FRAME, to estimate surface air concentrations of ammonia at 5 km and 1 km resolution for the UK network of Natura sites, optionally including calibration with the National Ammonia Monitoring Network. As a base indicator, we estimated the overall percentage area of the UK Natura network that exceeded critical level thresholds (‘Area Weighted Indicator’, AWI). We compared this with an alternative approach, estimating the percentage number of Natura sites where the critical level was exceeded (‘Designation Weighted Indicator’, DWI), which we consider more relevant under the terms of the Habitats Directive.Using the AWI (with 1 km calibrated ammonia), we estimate that 11.2%, 1.3% and 0.2% area of the UK Natura network exceeds the critical level values of 1, 2 and 3 μg NH3 m?3, respectively. By contrast, using the DWI, the equivalent exceedances are 59.1%, 23.6% and 9.8%. The highest regional exceedance (DWI, critical level 1 μg NH3 m?3) was calculated for England (91.9% exceeded), and the lowest for Scotland (24.0% exceeded). High resolution maps show that the larger threat estimated by the DWI approach is explained by (i) an anti-correlation between NH3 concentration and Natura site area and (ii) the fact that exceedance over part of a Natura site is considered to represent a threat to the integrity of the whole site. 相似文献
98.
A fashionable field of enquiry – the relationship between expressed attitudes and actual behaviour in the context of sustainable development – is complex (Staats et al. 2004) and difficult to apply in a policy-relevant manner (Aall and Norland 2005). However, recent research indicates that the use of a household diary can be beneficial in helping to quantify household environmental impact, in educating householders about their impact, and in identifying major ‘behavioural turning points’, where householders may focus efforts to reduce their environmental impact (Hunter et al. 2006). In other words, the use of a diary by householders is a potentially powerful tool in encouraging and facilitating desired behavioural change. This paper reports on the initial findings of an innovative study that assessed the use of a household diary approach as a means of framing and collecting household environmental data and, critically, as an educational vehicle for bringing about behavioural change. Based on the initial findings, it is clear that there is some potential to develop practical policy measures that empower householders by allowing them to better grasp their environmental impact and, consequently, recoup positive implications in terms of financial savings (e.g. reducing the amount of food thrown out) and health benefits (e.g. more walking/cycling). 相似文献
99.
Soils are a key component of the terrestrial carbon cycle as they contain the majority of terrestrial carbon. Soil microorganisms mainly control the accumulation and loss of this carbon. However, traditional concepts of soil carbon stabilisation failed so far to account for environmental and energetic constraints of microorganisms. Here, we demonstrate for the first time that these biological limitations might have the overall control on soil carbon stability. In a long-term experiment, we incubated 13C-labelled compost with natural soils at various soil carbon concentrations. Unexpectedly, we found that soil carbon turnover decreased with lower carbon concentration. We developed a conceptual model that explained these observations. In this model, two types of particles were submitted to random walk movement in the soil profile: soil organic matter substrate and microbial decomposers. Soil carbon turnover depended only on the likelihood of a decomposer particle to meet a substrate particle; in consequence, carbon turnover decreased with lower carbon concentration, like observed in the experiment. This conceptual model was able to simulate realistic depth profiles of soil carbon and soil carbon age. Our results, which are simply based on the application of a two-step kinetic, unmystify the stability of soil carbon and suggest that observations like high carbon ages in subsoil, stability of carbon in fallows and priming of soil carbon might be simply explained by the probability to be decomposed. 相似文献
100.
Steen DA McClure CJ Brock JC Rudolph DC Pierce JB Lee JR Humphries WJ Gregory BB Sutton WB Smith LL Baxley DL Stevenson DJ Guyer C 《Ecological applications》2012,22(4):1084-1097
Habitat loss and degradation are thought to be the primary drivers of species extirpations, but for many species we have little information regarding specific habitats that influence occupancy. Snakes are of conservation concern throughout North America, but effective management and conservation are hindered by a lack of basic natural history information and the small number of large-scale studies designed to assess general population trends. To address this information gap, we compiled detection/nondetection data for 13 large terrestrial species from 449 traps located across the southeastern United States, and we characterized the land cover surrounding each trap at multiple spatial scales (250-, 500-, and 1000-m buffers). We used occupancy modeling, while accounting for heterogeneity in detection probability, to identify habitat variables that were influential in determining the presence of a particular species. We evaluated 12 competing models for each species, representing various hypotheses pertaining to important habitat features for terrestrial snakes. Overall, considerable interspecific variation existed in important habitat variables and relevant spatial scales. For example, kingsnakes (Lampropeltis getula) were negatively associated with evergreen forests, whereas Louisiana pinesnake (Pituophis ruthveni) occupancy increased with increasing coverage of this forest type. Some species were positively associated with grassland and scrub/shrub (e.g., Slowinski's cornsnake, Elaphe slowinskii) whereas others, (e.g., copperhead, Agkistrodon contortrix, and eastern diamond-backed rattlesnake, Crotalus adamanteus) were positively associated with forested habitats. Although the species that we studied may persist in varied landscapes other than those we identified as important, our data were collected in relatively undeveloped areas. Thus, our findings may be relevant when generating conservation plans or restoration goals. Maintaining or restoring landscapes that are most consistent with the ancestral habitat preferences of terrestrial snake assemblages will require a diverse habitat matrix over large spatial scales. 相似文献