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After Hurricane Rita, the need for systematic and quantitative assessments of evacuation planning and operations strategies was recognized. Both contra-flow operation and phased evacuation were put into rigorous analysis through a large-scale regional traffic simulation modeling approach. After extensive data preparation and model developments, the Central Texas Evacuation network (CTE) in Dynamic Urban Systems in Transportation (DynusT) was created. The analysis results are presented and elaborated through relevant measures of effectiveness as well as innovative visualization techniques in this paper. The results show that the contra-flow strategy yields considerable improvements in all evacuation corridors in spite of several hot spots requiring further mitigation. The phased evacuation strategy in conjunction with the contra-flow strategy brings forth further improvements, particularly for the coastal high risk zones. [ABSTRACT FROM AUTHOR]

This study aims to quantify water appropriation and the potential production of algal bio-oil using freshwater and municipal wastewater effluent ( MWW) as an alternative water resource. The county-level analysis focuses on open-pond algae cultivation systems located in 17 states in the southern United States. Several scenarios were developed to examine the water availability for algae bio-oil production under various water resource mixing MWW and freshwater. The results of the analysis indicate that water availability can significantly affect the selection of an algal refinery site and therefore the potential production of algal bio-oil. The production of one liter of algal bio-oil requires 1036-1666 L of water at the state level, in which 3% to 91% can be displaced by MWW, depending on the biorefinery location. This water requirement corresponds to a total of 25 billion liters of bio-oil produced if the spatially and temporally available MWW effluent together with 10% of total available freshwater are used. The production of algal bio-oil is only 14% of estimated production under the assumption that all of the water demand can be fulfilled without any restriction. In addition, if only the spatially and temporally available effluent is used as the sole source of water, the total bio-oil production is estimated to be 9 billion liters. This study not only quantifies the water demands of the algal bio-oil, but it also elucidates the importance of taking water sustainability into account in the development of algal bio-oil. © 2013 Society of Chemical Industry and John Wiley & Sons, Ltd [ABSTRACT FROM AUTHOR]

Low serum 25-hydroxy vitamin D (25OHD) predicts a higher cardiovascular risk in the general population. Because patients with chronic kidney disease are more likely to have low serum 25OHD, we determined the relationship between hypovitaminosis D and death in this group. Analysis was done using a cohort composed of 3011 patients from the Third National Health and Nutrition Examination Survey who had chronic kidney disease but were not on dialysis and who had a mean follow-up of 9 years. In analyses adjusted for demographics, cardiovascular risk factors, serum phosphorus, albumin, hemoglobin, stage of chronic kidney disease, albuminuria, and socioeconomic status, individuals with serum 25OHD levels less than 15 ng/ml had an increased risk for all-cause mortality when compared to those with levels over 30 ng/ml. This significantly higher risk for death with low serum 25OHD was evident in 15 of the 23 subgroups. The higher risk for cardiovascular and non-cardiovascular mortality became statistically nonsignificant on multivariable adjustment. The trend for higher mortality in patients with 25OHD levels 15–30 ng/ml was not statistically significant. Our results indicate there is a graded relationship between serum 25OHD and the risk for death among subjects with chronic kidney disease who are not undergoing dialysis. Randomized, controlled trials are needed to conclusively determine whether vitamin D supplementation reduces mortality. [ABSTRACT FROM AUTHOR]

Purpose of Review: There have been differential changes in outcomes of patients treated with in-center hemodialysis and peritoneal dialysis. In light of these changes, providers and practices should reevaluate the utilization of peritoneal dialysis., Recent Findings: Accumulating evidence confirms that the present distribution of dialysis modality in the United States does not reflect patient choice. Furthermore, in most recent cohorts, the 5-year adjusted survival of patients treated with hemodialysis and peritoneal dialysis is remarkably similar (35 and 33% respectively). Similar results have been reported from Canada, Australia, and New Zealand. Moreover, health-related quality of life of peritoneal dialysis patients are no different from that reported by those treated with nocturnal hemodialysis. Finally, an expansion of use of peritoneal dialysis for the treatment of end-stage renal disease makes economic sense for the taxpayers - the payors for dialysis services., Summary: The improvement in outcomes of peritoneal dialysis patients makes a compelling argument for the expansion of the use of the therapy for the treatment of end-stage renal disease in the United States. We think that 20-40% of patients can be treated with peritoneal dialysis. However, any expansion in use should be done gradually and should include training healthcare providers while continuously monitoring patient outcomes.

Recent reports indicate a decreased mortality risk for patients on chronic peritoneal dialysis in the United States. We sought to determine whether a higher use of automated versus continuous ambulatory peritoneal dialysis was associated with this improvement. Analyses were carried out using data from the United States Renal Data System on 66,381 incident patients on chronic peritoneal dialysis in the years 1996-2004 that were adjusted for demographic, clinical, laboratory and dialysis facility characteristics. Patients were followed until the time of transfer to other modes of dialysis, transplant, or death, whichever occurred first, or until their last follow-up through September 2006. Over time, the risks were substantially reduced such that the adjusted hazard ratios for death or technique failure of these patients in the 2002-2004 period were 0.55 (0.53, 0.57) and 0.62 (0.59, 0.64), respectively, compared with those of incident patients during the years 1996-1998. The risk improvements for both modes of dialysis were, however, found to be similar. Under intent-to-treat, time-dependent, and as-treated analysis, there was little or no difference in risk for death or in technique failure. Thus, the improved chronic peritoneal dialysis outcomes cannot be attributed to a greater use of automated peritoneal dialysis.

Prior studies have estimated that a liter of bioethanol requires 263-784 L of water from corn farm to fuel pump, but these estimates have failed to account for the widely varied regional irrigation practices. By using regional time-series agricultural and ethanol production data in the U.S., this paper estimates the state-level field-to-pump water requirement of bioethanol across the nation. The results indicate that bioethanol's water requirements can range from 5 to 2138 L per liter of ethanol depending on regional irrigation practices. The results also show that as the ethanol industry expands to areas that apply more irrigated water than others, consumptive water appropriation by bioethanol in the U.S. has increased 246% from 1.9 to 6.1 trillion liters between 2005 and 2008, whereas U.S. bioethanol production has increased only 133% from 15 to 34 billion liters during the same period. The results highlight the need to take regional specifics into account when implementing biofuel mandates.