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911.
912.
Two distinctive, independently developed technologies, geographic information systems (GIS) and predictive water resource models, are being interfaced with varying degrees of sophistication in efforts to simultaneously examine spatial and temporal phenomena. Neither technology was initially developed to interact with the other, and as a result, multiple approaches to interface GIS with water resource models exist. Additionally, continued model enhancements and the development of graphical user interfaces (GUIs) have encouraged the development of application “suites” for evaluation and visualization of engineering problems. Currently, disparities in spatial scales, data accessibility, modeling software preferences, and computer resources availability prevent application of a universal interfacing approach. This paper provides a state‐of‐the‐art critical review of current trends in interfacing GIS with predictive water resource models. Emphasis is placed on discussing limitations to efficient interfacing and potential future directions, including recommendations for overcoming many current challenges.  相似文献   
913.
Shredder residues produced in plants processing waste electric and electronic equipment are excluded from material recycling due to a variety of polymeric materials and the presence of brominated flame retardants (BFR), which might contain banned polybrominated diphenyl ethers or toxic polybrominated dioxins and furans (PBDD/F). Herein we present a technological approach to transfer a significant portion of the shredder residue into recycled polymers. The technological approach consists of a density-based enrichment of styrenics, which are subjected to a solvolysis process (CreaSolv process) in a second stage. This stage allows the elimination of non-target polymers and extraction of BFR and PBDD/F. Pilot processing of 11.5 and 50 kg shredder residues indicated a material yield of about 50% in the density stage and 70-80% in the CreaSolv process, and an effective removal of BFR additives. The recycled products were proved to comply with threshold values defined by the European directive on the restriction of hazardous substances (RoHS) and the German Chemikalienverbotsverordnung. Mechanical material properties exhibited high tensile and flexural modules as well as slight impact strength, which qualify the products for applications in new electronic equipment.  相似文献   
914.
915.
Paralytic ileus of the small bowel was diagnosed in a fetus at 32 weeks' gestation after referral because of polyhydramnios. The mother had taken clonazepam, a benzodiazepine, and carbamazepine during the entire pregnancy for epilepsy. All known causes for the ileus were ruled out and at 20 months the boy has developed normally. We conclude that maternal anticonvulsant drug intake was very likely the cause of the paralytic ileus. This side-effect is known in experimental and clinical pharmacology but has not yet been described in human fetuses.  相似文献   
916.
917.
918.
Abstract: Valid modeling of habitats and populations of Greater Sage-Grouse ( Centrocercus urophasianus) is a critical management need because of increasing concern about population viability. Consequently, we evaluated the performance of two models designed to assess landscape conditions for Greater Sage-Grouse across 13.6 million ha of sagebrush steppe in the interior Columbia Basin and adjacent portions of the Great Basin of the western United States (referred to as the basin). The first model, the environmental index model, predicted conditions at the scale of the subwatershed (mean size of approximately 7800 ha) based on inputs of habitat density, habitat quality, and effects of human disturbance. Predictions ranged on a continuous scale from 0 for lowest environmental index to 2 for optimal environmental index. The second model, the population outcome model, predicted the composite, range-wide conditions for sage grouse based on the contribution of environmental index values from all subwatersheds and measures of range extent and connectivity. Population outcomes were expressed as five classes (A through E) that represented a gradient from continuous, well-distributed populations (outcome A) to sparse, highly isolated populations with a high likelihood of extirpation (outcome E). To evaluate performance, we predicted environmental index values and population outcome classes in areas currently occupied by sage grouse versus areas where extirpation has occurred. Our a priori expectations were that models should predict substantially worse environmental conditions ( lower environmental index) and a substantially higher probability of extirpation ( lower population outcome class) in extirpated areas. Results for both models met these expectations. For example, a population outcome of class E was predicted for extirpated areas, as opposed to class C for occupied areas. These results suggest that our models provided reliable landscape predictions for the conditions tested. This finding is important for conservation planning in the basin, where the models were used to evaluate management of federal lands for sage grouse.  相似文献   
919.

Objective

This study aimed to assess the diagnostic yield of prenatal genetic testing using trio whole exome sequencing (WES) and trio whole genome sequencing (WGS) in pregnancies with fetal anomalies by comparing the results with conventional chromosomal microarray (CMA) analysis.

Methods

A total of 40 pregnancies with fetal anomalies or increased nuchal translucency (NT ≥ 5 mm) were included between the 12th and 21st week of gestation. Trio WES/WGS and CMA were performed in all cases.

Results

The trio WES/WGS analysis increased the diagnostic yield by 25% in cases with negative CMA results. Furthermore, all six chromosomal aberrations identified by CMA were independently detected by WES/WGS analysis. In total, 16 out of 40 cases obtained a genetic sequence variant, copy number variant, or aneuploidy explaining the phenotype, resulting in an overall WES/WGS diagnostic yield of 40%. WES analysis provided a more reliable identification of mosaic sequence variants than WGS because of its higher sequencing depth.

Conclusions

Prenatal WES/WGS proved to be powerful diagnostic tools for fetal anomalies, surpassing the diagnostic yield of CMA. They have the potential to serve as standalone methods for prenatal diagnosis. The study highlighted the limitations of WGS in accurately detecting mosaic variants, which is particularly relevant when analyzing chorionic villus samples.  相似文献   
920.
Coagulation followed by floc separation is a key process for the removal of algal organic matter(AOM) in water treatment. Besides optimizing coagulation parameters,knowledge of the properties of AOM-flocs is essential to maximizing AOM removal.However, the impact of AOM on the floc properties remains unclear. This study investigated how peptides/proteins derived from the cellular organic matter(COM) of the cyanobacterium Microcystis aeruginosa influenced the size, structure, and shape of flocs formed at different shear rates(G). Flocs formed by kaolinite, COM-peptides/proteins and a mixture of the same were studied, and the effect of intermolecular interactions between floc components on floc properties was assessed. The coagulation experiments were performed in a Taylor–Couette reactor, with aluminum(Al) or ferric sulphate(Fe) utilized as coagulants. Image analysis was performed to gauge floc size and obtain data on fractal dimension. It was found that floc properties were affected by the presence of the COM-peptides/proteins and the coagulant used. COM-peptides/proteins increased floc size and porosity and widened floc size distributions. The Fe coagulant produced larger and less compact flocs than Al coagulant. Moreover, the decrease in floc size that occurred in parallel with increase in shear rate was not smooth in progress. A rapid change for the kaolinite-coagulant suspension and two rapid changes for the suspensions containing COM were observed. These were attributed to various intermolecular interactions between floc components participating in coagulation at different G. Based on the results obtained, shear rates suitable for efficient separation of flocs containing COM were suggested.  相似文献   
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