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261.
Two male sibs with severe congenital megacystis-microcolon-intestinal hypoperistalsis syndrome (MMIHS) are presented. Both had enlarged bladder and hydronephrosis due to reduced bladder emptying, decreased bowel motility, and malrotation of the colon. Repeated careful ultrasound examination of the urinary tract in the second sib failed to show significant bladder enlargement prior to 25 weeks' gestation, which has been considered to be a reliable prenatal diagnostic sign for MMIHS. Slight bilateral enlargement of the renal pelves was noted at 21 weeks' gestation, and this may represent the earliest prenatally-detectable observation in this disease. Although more females than males with this condition have been reported, our cases provide support for an autosomal recessive mode of inheritance with a similar recurrence risk for both sexes. 相似文献
262.
Scott W. Ator Anthony R. Olsen Ann M. Pitchford Judith M. Denver 《Journal of the American Water Resources Association》2003,39(4):873-885
ABSTRACT: A stratified, spatially balanced sample with unequal probability selection was used to design a multipurpose survey of headwater streams in the Mid‐Atlantic Coastal Plain. Objectives for the survey include unbiased estimates of regional stream conditions, and adequate coverage of unusual but significant environmental settings to support empirical modeling of the factors affecting those conditions. The design and field application of the survey are discussed in light of these multiple objectives. A probability (random) sample of 175 first‐order nontidal streams was selected for synoptic sampling of water chemistry and benthic and riparian ecology during late winter and spring 2000. Twenty‐five streams were selected within each of seven hydrogeologic subre‐gions (strata) that were delineated on the basis of physiography and surficial geology. In each subregion, unequal inclusion probabilities were used to provide an approximately even distribution of streams along a gradient of forested to developed (agricultural or urban) land in the contributing watershed. Alternate streams were also selected. Alternates were included in groups of five in each subregion when field reconnaissance demonstrated that primary streams were inaccessible or otherwise unusable. Despite the rejection and replacement of a considerable number of primary streams during reconnaissance (up to 40 percent in one subregion), the desired land use distribution was maintained within each hydrogeologic subregion without sacrificing the probabilistic design. 相似文献
263.
Infants, children, adolescents, and pregnant and lactating women have been described as groups with special needs. Regardless of diet chosen, these groups are at higher risk for nutritional deficiencies than adult males. Vegan diets can be safely used by these groups if foods, and in some instances supplements, are selected which provide a healthful and nutritionally adequate diet. Guidelines have been developed for those choosing to follow vegan diets. In many instances vegan diets offer health benefits. Studies of vegans are limited by factors such as heterogeneity of diets, the size and extent of this type of study, and difficulty in subject identification. There is a scarcity of studies of newer vegetarians who are often more mainstream than the vegetarians of the 1960s and 1970s. In some instances this has led to assumptions about today's vegans which are based on out-dated information. Thorough scientific studies of today's vegetarians, especially of those in groups with special needs, are needed. 相似文献
264.
Américo José Preto Borges Rachel Ann Hauser-DavisTerezinha Ferreira de Oliveira 《Journal of Cleaner Production》2011,19(15):1763-1769
Red mud is a residue obtained by the Bayer process during alumina production, and its disposal is an environmental problem due to its caustic nature, metal and radionuclide content and alkalinity. The present study analyzed five different filtration factors with two levels each in order to improve filtration and, thus, reduce the caustic content of this residue. This study was conducted at the Alumina do Norte do Brasil S.A (ALUNORTE) alumina plant, located in Pará, Brazil, in one of the six filters at the plant. Results show that the condensate is the primary factor in caustic red mud concentrations, followed by dilution, rotation and level of the basin filter. The interactions between dilution and the level of the basin filter were considered significant, as was the interaction amongst the three effects: dilution, level of the basin filter and vacuum. The model adjustment regarding the filtration process allows for the production of a final red mud product with lower caustic concentrations, resulting in economic advantages due to higher caustic recovery in filtration and lower caustic concentration in the red mud residue, which leads to an environmentally safer residue. 相似文献
265.
Christian Hermans Ann C. Vandaele Michel Carleer Sophie Fally Réginald Colin Alain Jenouvrier Bernard Coquart Marie-France Mérienne 《Environmental science and pollution research international》1999,6(3):151-158
Absorption spectroscopy, which is widely used for concentration measurements of tropospheric and stratospheric compounds,
requires precise values of the absorption cross-sections of the measured species. NO2, O2 and its collision-induced absorption spectrum, and H2O absorption cross-sections have been measured at temperature and pressure conditions prevailing in the Earth’s atmosphere.
Corrections to the generally accepted analysis procedures used to resolve the convolution problem are also proposed. 相似文献
266.
Ann Seiter Linda Newberry Pam Edens 《Journal of the American Water Resources Association》2000,36(6):1211-1217
ABSTRACT: Over the last decade, the Jamestown S'Klallam Tribe has formed partnerships with their neighboring county government, irrigation districts, property owners, and state and federal agencies in an effort to save the dwindling runs of Dungeness River salmon. Although considerable progress has been made to begin the recovery process, the watershed is included in recent listings of Pacific Northwest salmon under the Endangered Species Act. Under the coordination of an active watershed council, significant improvements have been made in water conservation and the protection of instream flows. Cooperation between the Tribe, irrigation districts and the Washington Department of Ecology resulted in a trust water rights agreement and the reduction of late summer water withdrawals by one‐third. 相似文献
267.
Koffi L. Dagnon Christopher Thellen Jo Ann Ratto Nandika A. D’Souza 《Journal of Polymers and the Environment》2010,18(4):510-522
The degradation of poly(3-hydroxybutyrate-co-4-hydroxybutyrate) (P(3HB-co-4HB)) coated brown Kraft paper and its components in a constructed soil environment was investigated. Soil burial tests were
carried out over 8 weeks. Weight loss measurements, photographic analysis, environmental scanning electron microscopy (ESEM),
dynamic mechanical analysis (DMA) and differential scanning calorimetry (DSC) were conducted to assess the physical, structural,
mechanical and thermal behavior before and after the soil burial test. Paper showed the highest physical degradation and weight
loss. With respect to the control samples, the stiffness of the partially degraded samples decreased. The overall crystallinity
of the biopolymer and the coated paper was affected significantly by burial. The pure biopolymer’s weight loss was substantially
enhanced when coated on paper. This result reveals a possible increased microbial population in the coated paper relative
to the pure biopolymer. 相似文献
268.
Use of statistical tools to evaluate the reductive dechlorination of high levels of TCE in microcosm studies 总被引:1,自引:0,他引:1
Harkness M Fisher A Lee MD Mack EE Payne JA Dworatzek S Roberts J Acheson C Herrmann R Possolo A 《Journal of contaminant hydrology》2012,131(1-4):100-118
A large, multi-laboratory microcosm study was performed to select amendments for supporting reductive dechlorination of high levels of trichloroethylene (TCE) found at an industrial site in the United Kingdom (UK) containing dense non-aqueous phase liquid (DNAPL) TCE. The study was designed as a fractional factorial experiment involving 177 bottles distributed between four industrial laboratories and was used to assess the impact of six electron donors, bioaugmentation, addition of supplemental nutrients, and two TCE levels (0.57 and 1.90 mM or 75 and 250 mg/L in the aqueous phase) on TCE dechlorination. Performance was assessed based on the concentration changes of TCE and reductive dechlorination degradation products. The chemical data was evaluated using analysis of variance (ANOVA) and survival analysis techniques to determine both main effects and important interactions for all the experimental variables during the 203-day study. The statistically based design and analysis provided powerful tools that aided decision-making for field application of this technology. The analysis showed that emulsified vegetable oil (EVO), lactate, and methanol were the most effective electron donors, promoting rapid and complete dechlorination of TCE to ethene. Bioaugmentation and nutrient addition also had a statistically significant positive impact on TCE dechlorination. In addition, the microbial community was measured using phospholipid fatty acid analysis (PLFA) for quantification of total biomass and characterization of the community structure and quantitative polymerase chain reaction (qPCR) for enumeration of Dehalococcoides organisms (Dhc) and the vinyl chloride reductase (vcrA) gene. The highest increase in levels of total biomass and Dhc was observed in the EVO microcosms, which correlated well with the dechlorination results. 相似文献
269.
Lee KC Shults RA Greenspan AI Haileyesus T Dellinger AM 《Journal of Safety Research》2008,39(1):25-31
INTRODUCTION: In 2004, more than 180,000 child passengers aged 相似文献
270.