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81.
This paper presents a sonographic diagnosis of exencephaly made during the last trimester of gestation. The sonogram showed the absence of bones in the cranial vault together with the presence of a disorganized cerebral mass, with loss of its normal anatomy. Post-partum examination of the newborn confirmed the findings of the sonogram. We briefly review the characteristics of exencephaly, its aetiology, and its relationship to anencephaly.  相似文献   
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This study was conducted to evaluate the effect of commercially available engineered iron oxide nanoparticles coated with a surfactant (ENPFe-surf) on effluent water quality from a lab-scale sequencing batch reactor as a model secondary biological wastewater treatment. Results showed that ∼8.7% of ENPFe-surf applied were present in the effluent stream. The stable presence of ENPFe-surf was confirmed by analyzing the mean particle diameter and iron concentration in the effluent. Consequently, aqueous ENPFe-surf deteriorated the effluent water quality at a statistically significant level (p < 0.05) with respect to soluble chemical oxygen demand, turbidity, and apparent color. This implied that ENPFe-surf would be introduced into environmental receptors through the treated effluent and could potentially impact them.  相似文献   
85.
We present a synoptic, participatory vulnerability assessment tool to help identify the likely impacts of climate change and human activity in coastal areas and begin discussions among stakeholders on the coping and adaptation measures necessary to minimize these impacts. Vulnerability assessment tools are most needed in the tropical Indo-Pacific, where burgeoning populations and inequitable economic growth place even greater burdens on natural resources and support ecosystems. The Integrated Coastal Sensitivity, Exposure, and Adaptive Capacity for Climate Change (I-C-SEA Change) tool is built around a series of scoring rubrics to guide non-specialists in assigning scores to the sensitivity and adaptive capacity components of vulnerability, particularly for coral reef, seagrass, and mangrove habitats, along with fisheries and coastal integrity. These scores are then weighed against threat or exposure to climate-related impacts such as marine flooding and erosion. The tool provides opportunities for learning by engaging more stakeholders in participatory planning and group decision-making. It also allows for information to be collated and processed during a “town-hall” meeting, facilitating further discussion, data validation, and even interactive scenario building.

Electronic supplementary material

The online version of this article (doi:10.1007/s13280-015-0652-x) contains supplementary material, which is available to authorized users.  相似文献   
86.
The aim of this research is to establish the processing factors of six pesticides durong the preparation of fresh-cut lettuce and to assess the risk of ingestion of pesticide residues associated with the consumption of the same. A field study was carried out on the dissipation of three insecticides (imidacloprid, tebufenozide, cypermethrin) and three fungicides (metalaxyl, tebuconazole, azoxystrobin) during treatment conditions simulating those used for commercial fresh-cut lettuce. A simultaneous residue analysis method is validated using QuEChERS extraction with acetonitrile and CG-MS and LC-MS/MS analysis. The residues detected after field application never exceed the established Maximum Residue Limits. The processing factors were generally less than 1 (between 0.34 for tebufenozide and 0.53 for imidacloprid), indicating that the process, as a whole, considerably reduces residue levels in processed lettuce compared to fresh lettuce. It is confirmed that cutting, followed by washing and drying, considerably reduces the residues. A matrix effect in the dialyzation of the pesticides is observed and the in vitro study of bioavailability establishes a low percentage of stomach absorption capacity (<15%). The EDI/ADI ratios found in all cases were well below their ADI values, and the dietary exposure assessed (EDI) in fresh-cut lettuce showed no concerns for consumer health.  相似文献   
87.
EPA Reference Method 25 for measurement of total gaseous nonmethane organics as carbon in source emissions was evaluated in the laboratory and through field testing. Laboratory evaluation included development and testing of a nonmethane organic analyzer. In addition, a series of tests was performed on the condensate trap recovery system. The tests involved evaluation of two different condensate trap recovery system designs. The first design was very similar to the Federal Register design and the second design was a modified system for minimizing interference from trapped carbon dioxide. Field testing of the method was performed at two different printing plants. Both plants used carbon bed adsorption for solvent recovery and control of VOC emissions. Samples were collected from the inlet and outlet streams of adsorption units at both plants. In addition to Method 25 samples, Method 18 samples were collected for analysis by gas chromatography with flame ionization detection. The results of all the laboratory and field test samples are described.  相似文献   
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A new strategy for preparing composite samples of special interest and applicability in environmental screening studies is presented. The use of supersaturated experimental design matrices to conduct the sample composition of water sample specimens in screening studies is demonstrated. In contrast to well known conventional sample composition, this strategic approach provides analytical objects allowing the accurate prediction of analyte concentration levels in the original individual sample specimens while fixing the number of experiments to be carried out down to the very number of sample specimens. This will be of special importance when dealing with analytes that require complicated, labour intensive and expensive analytical processes. To reach this goal, two main conditions must be fulfilled. The first one is the sparsity effect (Pareto principle) which holds for the specimens in the sampling campaign. This means that the number of really anomalous or contaminated specimens, as compared to the total number of specimens to be analysed, is low. In environmental screening studies, frequently this situation can be reasonably assumed. The second condition is to have an effective manner to develop and solve the experimental designs required to build-up the composite samples. The challenging problem of screening PCBs in water samples has been tackled to show the usefulness of this strategic approach by combining chemometrically assisted sample composition and rapid analysis using solid-phase microextraction of the composite samples.  相似文献   
90.
The relationship between brood parasites and their hosts is usually assumed to result in coevolution, and documentation of changes in extant populations should thus be possible. Here we describe how the ejection rate of eggs of an obligate brood parasite, the great spotted cuckoo Clamator glandarius, by its host, the magpie Pica pica, has recently increased in an area in southern Spain. The ejection rate of great spotted cuckoo eggs in naturally parasitized nests of the magpie increased at a rate of 0.5% year' during the period 1982–1992. This result was verified in a number of field experiments using nonmimetic and mimetic model eggs. The rate of increase in ejection rate was 4.7% year-1 for mimetic eggs and 2.3% year-1 for nonmimetic eggs. There were clear differences in parasitism by the great spotted cuckoo between study plots and years, which makes comparisons of rates of parasitism between areas difficult without considering temporal variation. The recent increase in the ejection response of magpies to great spotted cuckoo eggs was not due to magpies using the abundance of cuckoos as a cue to the intensity of parasitism.  相似文献   
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