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1.
Iniencephaly is an uncommon, but not rare, lesion involving a fusion between the posterior occipital bone and the cervical spine. Many cases are associated with other cranio-cervical abnormalities and anencephaly, and most are associated with other structural abnormalities. The prognosis is thought to be dismal. We describe a male infant, one of twins, who was diagnosed prenatally as having iniencephaly. The child was born without complication and has grown and thrived. This is the fourth patient with long-term survival with iniencephaly. We recommend that non-directive counselling be applied when presenting the findings of iniencephaly to parents.  相似文献   
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Corporations own approximately 25% of all private land in the United States and, therefore, play an essential role in protecting biodiversity and maintaining natural habitats. The Wildlife Habitat Council (WHC) is a unique joint venture between conservation organizations and corporations to utilize corporate lands for ensuring biodiversity. The following case studies demonstrate how corporations have helped ensure healthy ecosystems and provided critical leadership in regional efforts. Amoco Chemical Company's Cooper River Plant has been instrumental in developing a cooperative project that involves numerous corporations, plantation owners, private citizens, nonprofit organizations, government agencies, and community groups to develop a comprehensive, ecosystem-based management plan for part of the Cooper River in Charleston, South Carolina, USA. The second case focuses on the Morie Company, a national sand quarry operator headquartered in southern New Jersey, USA. Morie Company is working with WHC, community groups, the Pinelands Commission, and other state regulatory agencies to explore sustainable development opportunities for companies within the Pinelands regulations. The third case takes us to DuPont Company's Asturias, Spain, site. A win—win success story of improved habitat and cost savings is the result of DuPont's concern for the environment, ability to work with a variety of groups, and willingness to consider innovative restoration techniques. The fourth case discusses Consumers Power Company's Campbell Plant in West Olive, Michigan, USA. In addition to implementing projects that contribute to biodiversity, Consumers Power has developed an environmental education field station to teach others about the importance of natural habitats. The final case highlights Baltimore Gas & Electric Company's efforts to maintain habitat for endangered species at their Calvert Cliffs site in Maryland.  相似文献   
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The distribution and impacts of different nitrogen pollutants are inextricably linked. To understand the problem fully, the interactions between the different pollutants need to be taken into account. This is particularly important when it comes to abatement techniques, since measures to reduce emissions of one nitrogen pollutant can often lead to an increase in another. This project represents a step towards greater understanding of these issues by linking together new and existing nitrogen flux models into a larger framework. The modelling framework has been constructed and some of the nitrogen flows between fields, farms and the atmosphere have been modelled for a UK study area for typical farm management scenarios.  相似文献   
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Mathematical models for the simulation of dense nonaqueous phase liquid tracer tests (DTTs) in laboratory columns and in the field are developed and examined. The DTT technique is a means of estimating the quantity of dense nonaqueous phase liquid (DNAPL) in a domain of interest in an aquifer. The two-dimensional field DTT model uses the Method of Principal Directions and an asymmetrical upwind algorithm for describing advective transport. Both models include diffusion transport of tracer into and from low-permeability porous structures such as clay lenses, as well as the mass transport kinetics of partitioning tracer to and from the DNAPL droplets. The dependence of the effluent tracer concentration curves on the parameters of the models is explored, and conclusions are drawn regarding the applicability of, and several possible problems with, the DTT technique. Model results indicate that the DTT performs well at locating distributed droplets of DNAPL, but is unlikely to be useful in the assessment of pooled DNAPL.  相似文献   
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Somatic coliphages were quantified in 459 produce and environmental samples from 11 farms in Northern Mexico to compare amounts of somatic coliphages among different types of fresh produce and environmental samples across the production steps on farms. Rinsates from cantaloupe melons, jalapeño peppers, tomatoes, and the hands of workers, soil, and water were collected during 2011–2012 at four successive steps on each farm, from the field before harvest through the packing facility, and assayed by FastPhage MPN Quanti-tray method. Cantaloupe farm samples contained more coliphages than jalapeño or tomato (p range <0.01–0.03). Across production steps, jalapeños had higher coliphage percentages before harvest than during packing (p = 0.03), while tomatoes had higher coliphage concentrations at packing than all preceding production steps (p range <0.01–0.02). These findings support the use of targeted produce-specific interventions at multiple points in the process of growing and packing produce to reduce the risk of enteric virus contamination and improve food safety during fruit and vegetable production.  相似文献   
8.
Minute traces of fluoride are found in the air of rural communities and of cities, having been contributed perhaps from volcanic effluvia, perhaps from burning coal, and perhaps from industrial sources. Atmospheres of urban areas of the U. S. have been found to contain from less than 0.2 μg F/m3 to as much as 1.9/μg F/m3. Fluorides released from industrial processes may release elemental fluorine, soluble gaseous fluorides, and soluble or insoluble fluoride dusts. At least in some instances inhaled fluoride from fluoride containing dusts has proven to be as biologically available as that from similar concentrations of inhaled HF. Measurement of the amount of fluoride excreted in the urine has proven to be a valuable index of exposure and a means of preventing cumulative injury. Average urinary F concentrations not exceeding 5 mg/liter, which corresponds approximately to a daily intake of 5 mg, are not associated with osteosclerosis in such workmen, and such changes are unlikely at daily intakes of 5 – 8 mg F. The amount of fluoride which is retained by an individual inhaling air containing 2.5 mg of fluoride dusts per m3 (the current TLV) is approximately 5-6 mg. A review of the literature describing the exposure of work forces to fluorides in industrial atmospheres indicates that concentrations have ranged from a fraction of a milligram/m3 to values mostly less than 10 mg/ml Surveys of populations living near installations emitting fluoride fumes or dusts indicate that, with few exceptions, the health of these persons has not been adversely affected. Many species of vegetation are far more susceptible to the effects of fluoride than is man, hence an air quality standard to protect vegetation will be far lower than those encountered in the factory, and can be expected to be of the order of 10 ppb or less. The probable daily intake of F at this level of exposure is 0.16 mg, an intake far below that required for the production of clear-cut effects in the human. Thus, air quality standards set to protect vegetation would contribute negligible quantities of F in terms of any possible adverse effect on human health, and would give a wide margin of protection for man.  相似文献   
9.
An adaptive management approach is necessary but not sufficient to address the long-term challenges of the Greater Yellowstone Ecosystem (GYE). Adaptive management, in turn, has its own particular challenges, of which we focus on two: science input, and stakeholder engagement. In order to frame our discussion and subsequent recommendations, we place the current management difficulties into their historical context, with special emphasis on the 1990 Vision document, which attempted a broad synthesis of management goals for the ecosystem. After examining these two key challenges in the context of the GYE, we make several recommendations that would allow for more effective ecosystem management in the long term. First, we recommend adoption of the GYE as a site for long-term science research and monitoring with an emphasis on integrative research, long-term federal funding, and public dissemination of data. Second, we conclude that a clearer prioritization of legislative mandates would allow for more flexible ecosystem management in the GYE, a region where conflicting mandates have historically led to litigation antithetical to effective ecosystem management. Finally, we recommend a renewed attempt at an updated Vision for the Future that engages stakeholders (including local landholders) substantively from the outset.  相似文献   
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Efforts to increase the use of waste materials as substitutes for virgin primary materials in industry are considered an important step toward sustainable industrial development. Some industries, however, have struggled to increase the recycling of materials for a variety of reasons. This study proposes a new approach to searching for recycling across industry boundaries. By focusing on an entire industry, the locations where economic and environmental benefit exists can be identified. This research identifies brick manufacturing facilities in the United States that are most likely to gain substantial economic benefit from the recycling of waste products. The results of this case study indicate that an industry-based approach can provide economically feasible pathways towards sustainable industrial development, especially for data rich manufacturing nations like the United States.  相似文献   
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