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This article reviews the regulation of lead in drinking water, highlighting its epidemiological, engineering and ethical aspects with a focus on the Flint water crisis. We first discuss water quality policy and its implementation with a focus on lead contamination of water, primarily from pipe systems between a water treatment facility and a tap. We then discuss physician's roles and ethical responsibilities regarding safe drinking water using a human rights framework. We argue that physicians can play an important role in safeguarding drinking water in their communities by being vigilant, honoring the community's trust in them, and warning, educating and empowering patients and broader communities so as to protect tap water safety and public health. [ABSTRACT FROM AUTHOR]

Because of institutional resource constraints, dual-listed courses will persist in most universities' programs of study. The pedagogical differences between undergraduate and graduate STEM student groups and the underlying distinction in intellectual development levels between the two student groups complicate the inclusion of undergraduates in dual-listed courses. Active learning techniques are a possible remedy to the hardships undergraduate students experience in graduate-level courses. Through an analysis of both undergraduate and graduate student experiences while enrolled in a dual-listed course, the authors implemented a variety of learning techniques used to complement the learning of both student groups and enhance deep discussion. This manuscript provides readers with details concerning the implementation of four active learning techniques used to help undergraduate students critically discuss primary literature. On the basis of undergraduate and graduate student perceptions and experiences, the authors suggest techniques to enhance the quality of dual-listed courses and provide an outline for easing the transition of these techniques into any science classroom. [ABSTRACT FROM AUTHOR]

This paper presents a tool for calculating the Palmer Drought Severity Index (PDSI) and associated drought indices. The PDSI is a widely used drought index, yet the complexity and lack of transparency associated with the calculation of the PDSI makes it difficult for a researcher to independently calculate the index. Researchers are often forced to use PDSI values supplied by the National Climatic Data Center (NCDC) of the National Oceanic and Atmospheric Administration (NOAA) or some other third party. The MATLAB tool presented here is easy to use, thoroughly documented, and transparent. The tool was developed by checking an independently developed code against NCDC's FORTRAN code. Discrepancies between the MATLAB tool and the NCDC code are documented. Researchers using the tool will be able to easily calculate the Palmer drought indices for data inputs of any length and at any spatial scale. [ABSTRACT FROM AUTHOR]

Abstract  The blood feeding vampire bats emerged from New World leaf-nosed bats that fed on fruit and insects. Plasminogen activator, a serine protease that regulates blood coagulation, is known to be expressed in the saliva of Desmodus rotundus (common vampire bat) and is thought to be a key enzyme for the emergence of blood feeding in vampire bats. To better understand the evolution of this biological function, we studied the plasminogen activator (PA) genes from all vampire bat species in light of their feeding transition to bird and subsequently mammalian blood. We include the rare species Diphylla ecaudata and Diaemus youngi, where plasminogen activator had not previously been studied and demonstrate that PA gene duplication observed in Desmodus is not essential to the vampire phenotype, but relates to the emergence of predominant mammalian blood feeding in this species. Plasminogen activator has evolved through gene duplication, domain loss, and sequence evolution leading to change in fibrin-specificity and susceptibility to plasminogen activator inhibitor-1. Before undertaking this study, only the four plasminogen activator isoforms from Desmodus were known. The evolution of vampire bat plasminogen activators can now be linked phylogenetically to the transition in feeding behavior among vampire bat species from bird to mammalian blood. [ABSTRACT FROM AUTHOR]

Monomethyl ethers of oligoethylene glycols with different chain lengths were converted to trimethylsilyl derivatives by reacting with trimethylchlorosilane in the presence of triethylamine, or by directly refluxing with excess trimethylchlorosilane or hexamethyldisilazane. Similarly, two oligoethylene glycols were converted to bis(trimethylsilyl) derivatives. When doped with lithium bis(trifluoromethanesulfonyl)imide, these electrolytes have very high conductivity, generally >10−3 S cm−1. A full cell performance test using one of these new electrolytes (1NM3) showed excellent cyclability at room temperature. Introducing a second trimethylsilyl group decreases the conductivity of trimethylsilylated compounds. The thermal properties, viscosities and dielectric constants of the compounds were measured, and the effect of those on the conductivity is reported. Cyclic voltammetry experiments show that the trimethylsilylated compound (1NM2) of diethylene glycol monomethyl ether has greater electrochemical stability than its germanium and carbon analogues. [ABSTRACT FROM AUTHOR]