Exposure Characterization of Haloacetic Acids in Humans for Exposure and Risk Assessment Applications: An Exploratory Study

Disinfected water is the major source of haloacetic acids (HAAs) in humans, but their inter- and intra-individual variability for exposure and risk assessment applications is under-researched. Thus, we measured HAAs in cross-sectional and longitudinal urine and water specimens from 17 individuals. Five regulated HAAs—mono-, di-, and trichloroacetic acid (MCAA, DCAA, and TCAA) and mono- and dibromoacetic acid (MBAA and DBAA)—and one unregulated HAA—bromochloroacetic acid (BCAA)—were measured. Urinary DCAA, MBAA, DBAA, and BCAA levels were always below the limits of detection (LOD). Measured levels and interindividual variability of urinary MCAA were higher than urinary TCAA. Longitudinal urinary specimens showed MCAA levels peaked in after-shower specimens, while TCAA levels remain unchanged. Correlation between urinary MCAA and TCAA was moderate but statistically significant. The prevalence of MCAA and TCAA in urine suggest they can be considered as biomarkers of HAA. Peak urinary MCAA in post-shower specimens suggest MCAA captures short-term exposure via dermal and/or inhalation, while urinary TCAA captures long-term exposure via ingestion. However, further research is warranted in a large pool of participants to test the reliability of MCAA as exposure biomarker

Poly(3-hydroxybutyrate) hyperproduction by a global nitrogen regulator NtrB mutant strain of Paracoccus denitrificans PD1222

Paracoccus denitrificans PD1222 accumulates short-length polyhydroxyalkanoates, poly(3-hydroxybutyrate), under nitrogen-deficient conditions. Polyhydroxybutyrate metabolism requires the 3-ketoacyl-CoA thiolase PhaA, the acetoacetyl-CoA dehydrogenase/reductase PhaB and the synthase PhaC for polymerization. Additionally, P. denitrificans PD1222 grows aerobically with nitrate as sole nitrogen source. Nitrate assimilation is controlled negatively by ammonium through the two-component NtrBC system. NtrB is a sensor kinase that autophosphorylates a histidine residue under low-nitrogen concentrations and, in turn, transfers a phosphoryl group to an aspartate residue of the response regulator NtrC protein, which acts as a transcriptional activator of the P. denitrificans PD1222 nasABGHC genes. The P. denitrificans PD1222 NtrB mutant was unable to use nitrate efficiently as nitrogen source when compared to the wild-type strain, and it also overproduced poly(3-hydroxybutyrate). Acetyl-CoA concentration in the P. denitrificans PD1222 NtrB mutant strain was higher than in the wild-type strain. The expression of the phaC gene was also increased in the NtrB mutant when compared to the wild-type strain. These results suggest that accumulation of poly(3-hydroxybutyrate) in the NtrB mutant strain of PD1222 responds to the high levels of acetyl-CoA that accumulate in the cytoplasm as consequence of its inability to efficiently use nitrate as nitrogen source

Analytics4Action Evaluation Framework: A Review of Evidence-Based Learning Analytics Interventions at the Open University UK

There is an urgent need to develop an evidence-based framework for learning analytics whereby stakeholders can manage, evaluate, and make decisions about which types of interventions work well and under which conditions. In this article, we will work towards developing a foundation of an Analytics4Action Evaluation Framework (A4AEF) that is currently being tested and validated at the Open University UK. By working with 18 introductory large-scale modules for a period of two years across the five faculties and disciplines within the OU, Analytics4Action provides a bottom-up-approach for working together with key stakeholders within their respective contexts. A holistic A4AEF has been developed to unpack, understand and map the six key steps in the evidence-based intervention process. By means of an exemplar in health and social science, a practical illustration of A4AEF is provided. In the next 3-5 years, we hope that a rich, robust evidence-base will be presented to show how learning analytics can help teachers to make informed, timely and successful interventions that will help each learner to achieve the module’s learning outcomes

Resilience training in the workplace from 2003 to 2014: a systematic review

Over a decade of research attests to the importance of resilience in the workplace for employee well-being and performance. Yet, surprisingly, there has been no attempt to synthesize the evidence for the efficacy of resilience training in this context. The purpose of this study, therefore, is to provide a systematic review of work-based resilience training interventions. Our review identified 14 studies that investigated the impact of resilience training on personal resilience and four broad categories of dependent variables: (a) mental health and subjective well-being outcomes, (b) psychosocial outcomes, (c) physical/biological outcomes, and (d) performance outcomes. Findings indicated that resilience training can improve personal resilience, and is a useful means of developing mental health and subjective well-being in employees. We also found that resilience training has a number of wider benefits that include enhanced psychosocial functioning and improved performance. Due to the lack of coherence in design and implementation, we cannot draw any firm conclusions about the most effective content and format of resilience training. Therefore, going forward, it is vital that future research uses comparative designs to assess the utility of different training regimes, explores whether some people might benefit more/less from resilience training, and demonstrates consistency in terms of how resilience is defined, conceptualized, developed, and assessed

An examination of the cyanide derivative of bovine superoxide dismutase with electron-nuclear double resonance

The Cu(II) sites of native, azido- and cyano-derivatives of bovine superoxide dismutase (superoxide:superoxide oxidoreductase, EC 1.15.1.1) have been examined by electron-nuclear double resonance ENDOR). The ENDOR spectrum of the native protein taken at the gII extreme shows resolved structure due to the file directly coordinated N-atoms of the histidine ligands. These spectra are too complex for interpretation but suggest inequivalent coupling between the electronic spin and the four ligand N-atoms. By contrast, the azido protein reveals one type of nitrogen with well-resolved hyperfine and quadrupole splittings (Azz = 37.9+/- 1 MHz, Pzz = 1.54+/-0.02 MHz), and the cyano form reveals one well-resolved set of nitrogen lines (Azz =47.8 +/-0.4 MHz, Pzz =1.62+/-0.01 MHz) and one type of partially resolved nitrogen (Azz =37.0+/-1 MHz). The cyano form also reveals a complex spectrum in the low-frequency domain (1-10 MHz). Through isotopic substitution and computer simulation, the spectrum is shown to be a composite of the ENDOR from the remote imidazole nitrogens and the cyanide nitrogen. The component of the hyperfine constant perpendicular to the C14N bond axis is AN[perpendicular] =3.9+/-0.3 MHz and along the bond axis is AN[perpendicular] [approximate, equal]5.7 MHz. The quadrupole interaction appears to be greatest along the CN axis with Qz'z' = 1.0+/-0.1 MHz and Qx'x'y'y' [approximate]0. Based on an analysis of the hyperfine and quadrupole interactions seen at two extremes of the electron paramagnetic spectrum, we propose a square-planar arrangement of three imidazole nitrogen and one CN- carbon around the copper. Within this plane two imidazole nitrogens are strongly coupled and magnetically equivalent, the third is inequivalent (slightly weaker hyperfine interaction) and forms a trans relationship with the cyanide. This model is consistent with other observations on the cyano-derivative.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/23979/1/0000228.pd

MFA10 (MFA 2010)

Catalogue of a culminating student exhibition held at the Mildred Lane Kemper Art Museum in 2010. Content includes Foreword / Buzz Spector -- Thinking as making / Robert Gero -- A new set of conversations / Patricia Olynyk -- MFA 2010 graduates. Clyde Ashby / Aaron Bos-Wahl / Andrew Cozzens / John Early / Ryan James Fabel / Joel Fullerton / Mary Beth Hassan / Wenting Hsu / John Nicholas Hutchings/ Dani Kantrowitz / Larry Keaty / Mamie Korpela / Paola Laterza / Mad Mohre / Emily Moorhead / Jonathan Muehlke / Jessa Richardson / Nicolette Ross / Carlie Trosclair / About the Sam Fox School.https://openscholarship.wustl.edu/books/1007/thumbnail.jp

Long-term evolution of orbits about a precessing oblate planet: 1. The case of uniform precession

It was believed until very recently that a near-equatorial satellite would always keep up with the planet's equator (with oscillations in inclination, but without a secular drift). As explained in Efroimsky and Goldreich (2004), this opinion originated from a wrong interpretation of a (mathematically correct) result obtained in terms of non-osculating orbital elements. A similar analysis carried out in the language of osculating elements will endow the planetary equations with some extra terms caused by the planet's obliquity change. Some of these terms will be nontrivial, in that they will not be amendments to the disturbing function. Due to the extra terms, the variations of a planet's obliquity may cause a secular drift of its satellite orbit inclination. In this article we set out the analytical formalism for our study of this drift. We demonstrate that, in the case of uniform precession, the drift will be extremely slow, because the first-order terms responsible for the drift will be short-period and, thus, will have vanishing orbital averages (as anticipated 40 years ago by Peter Goldreich), while the secular terms will be of the second order only. However, it turns out that variations of the planetary precession make the first-order terms secular. For example, the planetary nutations will resonate with the satellite's orbital frequency and, thereby, may instigate a secular drift. A detailed study of this process will be offered in the subsequent publication, while here we work out the required mathematical formalism and point out the key aspects of the dynamics