The role of upstream water use on water stress in transboundary river basins: a global analysis

Upstream-downstream relationship remains one of the many challenges of transboundary water management. Water use of upstream countries has always impact on the downstream water availability and in some cases it might lead to increased water scarcity in downstream part of a basin. In this study, aim is to assess the change in water stress level due to water use of upstream countries in the world’s transboundary river basins. Water stress level was first calculated considering only own water use of a sub-basin and this was then compared to the situation when both, own and upstream water use, were taken into account. When only own water use was considered, 955 million people lived under water stress in world’s transboundary river basins. When the upstream water use was taken into account, the population under water stress increased by 6 percentage points (194 million people). The stress increased most in Asia (central and north-east parts), Africa and some parts of Europe. Further, the results were compared with International water Event Database (1950-2008) by Oregon State University to assess whether there is a link between increased water stress due to upstream water use and the occurrence of conflictive and cooperation events in the transboundary river basins. Although no direct relationship between these two variables was found, in many basins with high number of events also the stress index increased considerably due to upstream water use. In case of transboundary river basin management, one of the key challenges is allocating shared water resources, and their benefits. My findings are thus important for international water bodies where equitable water allocation is at the center of water conflicts

Split histidine kinases enable ultrasensitivity and bistability in two-component signaling networks

Bacteria sense and respond to their environment through signaling cascades generally referred to as two-component signaling networks. These networks comprise histidine kinases and their cognate response regulators. Histidine kinases have a number of biochemical activities: ATP binding, autophosphorylation, the ability to act as a phosphodonor for their response regulators, and in many cases the ability to catalyze the hydrolytic dephosphorylation of their response regulator. Here, we explore the functional role of “split kinases” where the ATP binding and phosphotransfer activities of a conventional histidine kinase are split onto two distinct proteins that form a complex. We find that this unusual configuration can enable ultrasensitivity and bistability in the signal-response relationship of the resulting system. These dynamics are displayed under a wide parameter range but only when specific biochemical requirements are met. We experimentally show that one of these requirements, namely segregation of the phosphatase activity predominantly onto the free form of one of the proteins making up the split kinase, is met in Rhodobacter sphaeroides. These findings indicate split kinases as a bacterial alternative for enabling ultrasensitivity and bistability in signaling networks. Genomic analyses reveal that up 1.7% of all identified histidine kinases have the potential to be split and bifunctional

Estimation of costs of zebra mussel invasion in the Ebro basin (2005-2009 period)

Este estudio presenta los costes monetarios que ha supuesto la invasión del mejillón cebra en la cuenca del Ebro desde el año 2005 al 2009 para los sectores que utilizan el agua en sus actividades. El impacto económico asociado a esta invasión se deriva tanto de los problemas de funcionamiento de las instalaciones afectadas como de los gastos añadidos por la limpieza y tratamientos de control de las mismas. La metodología de trabajo se basó en el análisis de una encuesta dirigida a los sectores energético, industrial, agrícola, lúdico-deportivo, administraciones públicas y abastecimientos, susceptibles de estar afectados por la invasión del mejillón cebra. En total se enviaron por vía postal y electrónica 1329 cuestionarios a distintos agentes de los diversos sectores. La tasa de respuesta fue del 28.4%, permitiendo detectar 103 afectados en la cuenca. Los resultados indican que los costes asociados a la expansión del mejillón cebra en la cuenca del Ebro no han cesado de crecer en los últimos años, llegando a alcanzar los 11.6 millones de euros en el periodo de estudio. Los sectores más implicados son las administraciones públicas, con un 55.1% del total de costes contabilizados seguidas de las empresas energéticas, con un 26.4%. Geográficamente, es en el Alto Ebro donde más dinero se ha invertido en la lucha contra esta especie invasora durante los cinco años de estudio.This study presents the monetary costs that the zebra mussel invasion has involved in the Ebro basin since 2005 to 2009 for the sectors which use water in their activities. The economic impact associated with this invasion is derived from the operation problems in affected facilities and the costs added due to the cleaning and control treatments. The work methodology is based on the analysis of the survey address to energetic, industrial, agricultural, recreational, public administrations and supplies sensitive to be affected by the zebra mussel invasion. In total, 1329 surveys were sent by post and email to different agents of several sectors. The response rate was 28.4%, allowing a detection of 103 affected users in the basin. The results indicate that costs associated to the zebra mussel expansion in the Ebro basin have not stopped to increase in the last years, reaching 11.6 millions of Euros in the period of study. The most implicated sectors are public administrations, with a 55.1% of the total costs followed by energetic companies, with a 26.4%. Geographically, it is in the High Ebro where more money has been invested in the fight against this alien species during the five years of studyCuenca Ebroespecie invasoraimpacto económicomejillón cebraEbro basinalien specieseconomic impactzebra musselPublishe

Estimación de los costes de la invasión del mejillón cebra en la cuenca del Ebro (periodo 2005-2009)

This study presents the monetary costs that the zebra mussel invasion has involved in the Ebro basin since 2005 to 2009 for the sectors which use water in their activities. The economic impact associated with this invasion is derived from the operation problems in affected facilities and the costs added due to the cleaning and control treatments. The work methodology is based on the analysis of the survey address to energetic, industrial, agricultural, recreational, public administrations and supplies sensitive to be affected by the zebra mussel invasion. In total, 1329 surveys were sent by post and email to different agents of several sectors. The response rate was 28.4%, allowing a detection of 103 affected users in the basin. The results indicate that costs associated to the zebra mussel expansion in the Ebro basin have not stopped to increase in the last years, reaching 11.6 millions of Euros in the period of study. The most implicated sectors are public administrations, with a 55.1% of the total costs followed by energetic companies, with a 26.4%. Geographically, it is in the High Ebro where more money has been invested in the fight against this alien species during the five years of study.Este estudio presenta los costes monetarios que ha supuesto la invasión del mejillón cebra en la cuenca del Ebro desde el año 2005 al 2009 para los sectores que utilizan el agua en sus actividades. El impacto económico asociado a esta invasión se deriva tanto de los problemas de funcionamiento de las instalaciones afectadas como de los gastos añadidos por la limpieza y tratamientos de control de las mismas. La metodología de trabajo se basó en el análisis de una encuesta dirigida a los sectores energético, industrial, agrícola, lúdico-deportivo, administraciones públicas y abastecimientos, susceptibles de estar afectados por la invasión del mejillón cebra. En total se enviaron por vía postal y electrónica 1329 cuestionarios a distintos agentes de los diversos sectores. La tasa de respuesta fue del 28.4%, permitiendo detectar 103 afectados en la cuenca. Los resultados indican que los costes asociados a la expansión del mejillón cebra en la cuenca del Ebro no han cesado de crecer en los últimos años, llegando a alcanzar los 11.6 millones de euros en el periodo de estudio. Los sectores más implicados son las administraciones públicas, con un 55.1% del total de costes contabilizados seguidas de las empresas energéticas, con un 26.4%. Geográficamente, es en el Alto Ebro donde más dinero se ha invertido en la lucha contra esta especie invasora durante los cinco años de estudio

Phosphate sink containing two-component signaling systems as tunable threshold devices.

Published onlineJournal ArticleResearch Support, Non-U.S. Gov'tSynthetic biology aims to design de novo biological systems and reengineer existing ones. These efforts have mostly focused on transcriptional circuits, with reengineering of signaling circuits hampered by limited understanding of their systems dynamics and experimental challenges. Bacterial two-component signaling systems offer a rich diversity of sensory systems that are built around a core phosphotransfer reaction between histidine kinases and their output response regulator proteins, and thus are a good target for reengineering through synthetic biology. Here, we explore the signal-response relationship arising from a specific motif found in two-component signaling. In this motif, a single histidine kinase (HK) phosphotransfers reversibly to two separate output response regulator (RR) proteins. We show that, under the experimentally observed parameters from bacteria and yeast, this motif not only allows rapid signal termination, whereby one of the RRs acts as a phosphate sink towards the other RR (i.e. the output RR), but also implements a sigmoidal signal-response relationship. We identify two mathematical conditions on system parameters that are necessary for sigmoidal signal-response relationships and define key parameters that control threshold levels and sensitivity of the signal-response curve. We confirm these findings experimentally, by in vitro reconstitution of the one HK-two RR motif found in the Sinorhizobium meliloti chemotaxis pathway and measuring the resulting signal-response curve. We find that the level of sigmoidality in this system can be experimentally controlled by the presence of the sink RR, and also through an auxiliary protein that is shown to bind to the HK (yielding Hill coefficients of above 7). These findings show that the one HK-two RR motif allows bacteria and yeast to implement tunable switch-like signal processing and provides an ideal basis for developing threshold devices for synthetic biology applications.Exeter University Science Strateg

Fluorinated Organic Molecules for Medicinal Applications

The significant applications of fluorinated molecules in the pharmaceutical, agrochemical, and material sciences make them attractive synthetic targets. Difluoromethylation methods are of exceptional value and a limited number of techniques are available to perform that transformation. The primary method for introducing CF2 groups is through the use of difluoroenolates. Difluoroenolates can be generated from α-keto pentafluoro gem -diols under mild conditions. The process involves the cleavage of carbon-carbon bond and the release of trifluoroacetate. The release of trifluoroacetate is a versatile method to generate fluorinated molecules. We explored the utility of this method in generating various fluorinated moieties including α,α-difluoroketones, α-deutero-α,α-difluoroketones, α,α-difluoromethyl sulfones, ?-deutero-α,α-difluoromethyl sulfones, monofluoro α-hydroxy ketones and α,α-difluorohalohydrins. We also endeavored to design and synthesize fluorinated molecules for biological applications. Our efforts were aimed at the use of a novel fluorinated β-hydroxy ketone scaffold developed in our lab to develop new agonists of the GABAB receptor. The value of GABAB agonists as muscle relaxants is well established, and interest in these agonists has been rekindled due to reports of new applications in managing drug and alcohol tolerance. We have developed several new analogues, characterized new structure-activity relationships of the fluorinated ?-hydroxy ketone scaffold, and identified more active agents. We are also interested in using fluorine as a tag to track anti-body drug conjugates (ADCs). The chemistry of ADC linkers has attracted a lot of interest recently. The cleavage of the linker is essential for the function of ADCs and in addition to this traditional role, linkers can provide a handle for tagging ADCs. The incorporation of fluorine into linkers minimally affects the sterics of the linker owing to the small size of fluorine atom while at the same time provides a tractable tag. A fluorinated ADC linker has been designed and its synthesis was explored

Techniques of Humiliation: Neoliberalism and the Noncitizen\u27s Body

This article argues that the disciplining of noncitizens becomes a constitutive characteristic of neoliberalism. Examining two narratives about bodily deprivation in detention centers, the study pursues the psychic life of statelessness through tragic testimonies that not only point to subjection, induced through techniques of humiliation, but also to the neoliberal contradiction between “inclusion” and practices of regulation. Readings interrogate the problem of normativity in neoliberalism. In particular, the article argues against normative presuppositions about both race and gender, demonstrating how this leads to the denial of medication and death in detention facilities

The Determinants of Rural Outmigration in the United States: 2010-2014

This study focuses on both economic and noneconomic determinants of geographical migration out of rural areas in the United States. In line with existing studies on individual’s decision to migrate from rural to urban areas, our analysis compares expected returns in rural to those in urban areas. Using annual U.S. countylevel count data spanning the period from 2010 to 2014, Fixed Effect and Negative Binomial methods are used to evaluate the effects of both economic and noneconomic variables on geographical outmigration from rural to urban areas. Determining factors investigated include distance between place of origin and potential destination, median household income, educational attainment, the poverty rate, the unemployment rate, a natural amenity index, the prevalence of primary healthcare providers and social associations. Findings suggest that higher expected returns in urban compared to rural areas contribute to releasing people out of rural areas in the United States. A large distance between origin and destination associated with high migration costs demotivate rural people to migrate to urban areas. On the other side, relatively high median household incomes, low unemployment rates, high level of education, a high presence of natural amenities, high level of access to primary healthcare providers in urban destination areas encourage rural people to migrate to urban areas. The poverty rate and social associations did not significantly affect rural outmigration decisions in the United States during the period studied

Complex Signs and Pseudo-composites

The purpose of the present paper is to try to find an answer to the question: how are complex signs analyzed in English morphology in the context of Axiomatic Functionalist Theory? The paper provides the tools for analyzing items like hatless, penniless, lioness, countess, hooliganism, and Marxism which are traditionally recognized as morphologically complex, each consisting of two morphemes: a free morpheme and a bound morpheme. With an eye to the notions sign and complex sign as envisaged in Axiomatic Functionalist Linguistics three of these items namely, penniless, countess and Marxism turn out to be unanalyzable, i.e. pseudo-composite

The Female-moneme in English: Semantic Considerations in Testing Moneme-ldentity

The purpose of the present paper is to explore the possibility of testing hypotheses for moneme identity by using an additional criterion of adequation with respect to semantic factors: a criterion concerning the assumption of recoverability of denotations of complex pleremes from the denotations of their constituents. I have taken the position that, in the final analysis, a particular complex plereme is a combination of two or more monemes holds on condition that the overall denotation of the complex in question is recoverable from the denotations of its constituents, plus, of course, from having a relatively clear (though necessarily rather approximate) idea of the semantic role played by the constructional relation between these constituents