WHO OWNS THE WATER? A CASE STUDY OF EL PASO DEL NORTE

This paper, first, reviews the report filed by the Western Water Policy Review Advisory Commission since it touches on all the major issues associated with water rights and uses in the Upper Rio Grande Basin, defined as that part of the river from the San Luis Valley in Colorado to Fort Quitman, Texas. Second, the paper reviews historical developments over water use and water rights and briefly discusses the major characteristics of El Paso del Norte that do and will have an impact on water supply and consumption. Then the paper reviews the positions of the major stakeholders in the Basin, paying particular attention to their legal arguments. Finally, the paper attempts to describe the possible alternative outcomes of the continuing struggle over water.Water rights--Rio Grande Valley, Water supply--Management --Texas--Lower Rio Grande Valley, Water supply--Management--Mexico--Rio Grande Valley, Resource /Energy Economics and Policy,

A graph-theory method for pattern identification in geographical epidemiology - a preliminary application to deprivation and mortality

Background: Graph theoretical methods are extensively used in the field of computational chemistry to search datasets of compounds to see if they contain particular molecular substructures or patterns. We describe a preliminary application of a graph theoretical method, developed in computational chemistry, to geographical epidemiology in relation to testing a prior hypothesis. We tested the methodology on the hypothesis that if a socioeconomically deprived neighbourhood is situated in a wider deprived area, then that neighbourhood would experience greater adverse effects on mortality compared with a similarly deprived neighbourhood which is situated in a wider area with generally less deprivation. Methods: We used the Trent Region Health Authority area for this study, which contained 10,665 census enumeration districts (CED). Graphs are mathematical representations of objects and their relationships and within the context of this study, nodes represented CEDs and edges were determined by whether or not CEDs were neighbours (shared a common boundary). The overall area in this study was represented by one large graph comprising all CEDs in the region, along with their adjacency information. We used mortality data from 1988-1998, CED level population estimates and the Townsend Material Deprivation Index as an indicator of neighbourhood level deprivation. We defined deprived CEDs as those in the top 20% most deprived in the Region. We then set out to classify these deprived CEDs into seven groups defined by increasing deprivation levels in the neighbouring CEDs. 506 (24.2%) of the deprived CEDs had five adjacent CEDs and we limited pattern development and searching to these CEDs. We developed seven query patterns and used the RASCAL (Rapid Similarity Calculator) program to carry out the search for each of the query patterns. This program used a maximum common subgraph isomorphism method which was modified to handle geographical data. Results: Of the 506 deprived CEDs, 10 were not identified as belonging to any of the seven groups because they were adjacent to a CED with a missing deprivation category quintile, and none fell within query Group 1 (a deprived CED for which all five adjacent CEDs were affluent). Only four CEDs fell within Group 2, which was defined as having four affluent adjacent CEDs and one non-affluent adjacent CED. The numbers of CEDs in Groups 3-7 were 17, 214, 95, 81 and 85 respectively. Age and sex adjusted mortality rate ratios showed a non-significant trend towards increasing mortality risk across Groups (Chi-square = 3.26, df = 1, p = 0.07). Conclusion: Graph theoretical methods developed in computational chemistry may be a useful addition to the current GIS based methods available for geographical epidemiology but further developmental work is required. An important requirement will be the development of methods for specifying multiple complex search patterns. Further work is also required to examine the utility of using distance, as opposed to adjacency, to describe edges in graphs, and to examine methods for pattern specification when the nodes have multiple attributes attached to them

Statistical analysis of the primary outcome in acute stroke trials

Common outcome scales in acute stroke trials are ordered categorical or pseudocontinuous in structure but most have been analyzed as binary measures. The use of fixed dichotomous analysis of ordered categorical outcomes after stroke (such as the modified Rankin Scale) is rarely the most statistically efficient approach and usually requires a larger sample size to demonstrate efficacy than other approaches. Preferred statistical approaches include sliding dichotomous, ordinal, or continuous analyses. Because there is no best approach that will work for all acute stroke trials, it is vital that studies are designed with a full understanding of the type of patients to be enrolled (in particular their case mix, which will be critically dependent on their age and severity), the potential mechanism by which the intervention works (ie, will it tend to move all patients somewhat, or some patients a lot, and is a common hazard present), a realistic assessment of the likely effect size, and therefore the necessary sample size, and an understanding of what the intervention will cost if implemented in clinical practice. If these approaches are followed, then the risk of missing useful treatment effects for acute stroke will diminish

Anxiety-like behaviour is regulated independently from sex, mating status, and the sex peptide receptor in Drosophila melanogaster

Sex differences in anxiety-related behaviours have been documented in many animals and are notable in human populations. A major goal in behaviour research is to understand why and how sex differences in cognitive-emotional states like anxiety arise and are regulated throughout life. Anxiety allows individuals to detect and respond to threats. Mating is a candidate regulator for anxiety because threats are likely to change, often in sex-specific ways, when individuals shift to a postmating reproductive state. However, we know little about how mating mediates anxiety-related behaviour in males and females, or about how males might influence female anxiety via seminal proteins transferred during mating. To address this gap, we examined anxiety-related behaviour in the fruit fly Drosophila melanogaster, an emerging model animal for anxiety, with respect to sex, mating and sex peptide, a seminal protein known to modulate a host of female postmating responses in fruit flies. We assayed anxiety-like behaviour using the open-field assay to assess individual avoidance of the interior of an arena (‘wall-following’ behaviour). We found sex differences in activity level, but no evidence for sex differences in wall-following behaviour. We found no effects of mating in either sex, or of the presence of the sex peptide receptor in females, on wall following. Our results suggest that anxiety is not one of the cognitive-emotional states regulated by mating and sex peptide in fruit flies, and that researchers need an alternative model for sex differences in anxiety

On the Correlated X-ray and Optical Evolution of SS Cygni

We have analyzed the variability and spectral evolution of the prototype dwarf nova system SS Cygni using RXTE data and AAVSO observations. A series of pointed RXTE/PCA observations allow us to trace the evolution of the X-ray spectrum of SS Cygni in unprecedented detail, while 6 years of optical AAVSO and RXTE/ASM light curves show long-term patterns. Employing a technique in which we stack the X-ray flux over multiple outbursts, phased according to the optical light curve, we investigate the outburst morphology. We find that the 3-12 keV X-ray flux is suppressed during optical outbursts, a behavior seen previously, but only in a handful of cycles. The several outbursts of SS Cygni observed with the more sensitive RXTE/PCA also show a depression of the X-rays during optical outburst. We quantify the time lags between the optical and X-ray outbursts, and the timescales of the X-ray recovery from outburst. The optical light curve of SS Cygni exhibits brief anomalous outbursts. During these events the hard X-rays and optical flux increase together. The long-term data suggest that the X-rays decline between outburst. Our results are in general agreement with modified disk instability models (DIM), which invoke a two-component accretion flow consisting of a cool optically thick accretion disk truncated at an inner radius, and a quasi-spherical hot corona-like flow extending to the surface of the white dwarf. We discuss our results in the framework of one such model, involving the evaporation of the inner part of the optically thick accretion disk, proposed by Meyer & Meyer-Hofmeister (1994).Comment: 24 pages, 8 figures, 2 tables, accepted for publication in Ap

Non-infectious intestinal conditions of sheep

Enteric disorders are common in sheep and have major economic consequences attributable to dags, production losses and mortalities. The purpose of this paper is to provide a review of non-infectious intestinal conditions in sheep with an emphasis on the role of nutrition and the effects of various nutritional factors. The principles of treatment and prevention are discussed, but not reviewed in detail. Non-infectious causes of scouring in sheep are generally not well understood. In particular, the role of various nutritional factors in determining faecal consistency (in both the presence and absence of infectious agents) warrants further investigation. Nutritional manipulation may provide options for management and prevention of scouring in sheep

Does colectomy affect the progression of primary sclerosing cholangitis? A systematic review and meta-analysis.

AIM: The aim of this systematic review was to determine if the human colon, through the lower gut-liver axis, drives PSC activity by assessing the progression of the disease in patients with and without colectomy for colonic disease. BACKGROUND: The gut-liver axis is involved in the pathogenesis of liver disease. Abnormal immune-mediated responses to intestinal microbiome are implicated in primary sclerosing cholangitis (PSC) however the mechanisms remain poorly understood. Currently, no single animal model recapitulates all attributes of PSC in humans and this limits further studies of gut-liver interactions. METHODS: A systematic search of PubMed, Medline, and Scopus was performed for articles that contained the terms "colectomy" or "bowel resection" AND "primary sclerosing cholangitis" up to 15th April 2018. Articles were reviewed by 2 reviewers and raw data collated. A Forest plot was used to illustrate the effect of colectomy on subsequent liver transplantation for PSC. Linear regression was used to estimate mortality risk. RESULTS: Colectomy appeared to have no effect on PSC progression, although high-quality studies were lacking. Rates of liver transplantation or transjugular intrahepatic portosystemic shunt for PSC were not affected by colectomy (OR 0.59, 95% CI 0.14 - 2.53, p=0.48). Mortality risk following colectomy in patients with PSC is 2.11% per year (95% CI 0.03% - 4.18%, p=0.032, R2 = 0.722). CONCLUSION: Current evidence is limited but suggests colectomy does not affect the progression of PSC in patients with colonic disease. Pathogenic micro-organisms or antigens that drive PSC may not be limited to the lower gut