Electrochemical behaviour of gamma hydroxybutyric acid at a platinum electrode in acidic medium

The electrooxidation of Gamma Hydroxybutyric Acid (GHB) on a polycrystalline platinum electrode is studied by cyclic voltammetry in acidic medium. Two oxidation peaks, A and B, are obtained in the positive scan within the potential range of the double layer region and of the platinum oxide region, respectively. In the negative going potential sweep an inverted oxidation peak with an onset partially overlapping with the tail of the cathodic peak for the reduction of the platinum oxide formed during the anodic scan is obtained (peak C). This inverted peak can be observed at a potential close to +0.2 V (vs Ag/AgCl at pH 2) and separated 0.4 and 0.8 V from the two other oxidation peaks obtained during the anodic scan and in such conditions that the surface is particularly activated to favour this electrochemical process. The response obtained in the electronic current for the different peaks when GHB concentration and scan rate were changed to allows inferring that these are the result of a potential dependent mechanism. The behaviour observed is according with the oxidation of the alcohol group to the corresponding aldehyde and carboxylic acid (succinic acid) as main products

Out-of-equilibrium evolution of quantum fields in the hybrid model with quantum back reaction

The hybrid model with a scalar "inflaton" field coupled to a "Higgs" field with a broken symmetry potential is one of the promising models for inflation and (p)reheating after inflation. We consider the nonequilibrium evolution of the quantum fields of this model with quantum back reaction in the Hartree approximation, in particular the transition of the Higgs field from the metastable "false vacuum" to the broken symmetry phase. We have performed the renormalization of the equations of motion, of the gap equations and of the energy density, using dimensional regularization. We study the influence of the back reaction on the evolution of the classical fields and of the quantum fluctuations. We observe that back reaction plays an important role over a wide range of parameters. Some implications of our investigation for the preheating stage after cosmic inflation are presented.Comment: 35 pages, 16 eps figures, revtex4; v2: typos corrected and references added, accepted for publication in Physical Review

IGSF1 does not regulate spermatogenesis or modify FSH synthesis in response to inhibins or activins

Loss-of-function mutations in the X-linked immunoglobulin superfamily, member 1 (IGSF1) gene result in central hypothyroidism, often associated with macroorchidism. Testicular enlargement in these patients might be caused by increases in follicle-stimulating hormone (FSH) levels, as IGSF1 has been proposed to function as an inhibin B receptor or as an inhibitor of activin type I receptor (ALK4) activity in pituitary gonadotrope cells. If true, loss of IGSF1 should lead to reduced inhibin B action or disinhibition of activin signaling, thereby increasing FSH synthesis. Here, we show that FSH levels and sperm counts are normal in male Igsf1 knockout mice, although testis size is mildly increased. Sperm parameters are also normal in men with IGSF1 deficiency, although their FSH levels may trend higher and their testes are enlarged. Inhibin B retains the ability to suppress FSH synthesis in pituitaries of Igsf1-knockout mice and IGSF1 does not interact with ALK4 or alter activin A/ALK4 stimulation of FSH beta (Fshb/FSHB) subunit transcription or expression. In light of these results, it is unlikely that macroorchidism in IGSF1 deficiency derives from alterations in spermatogenesis or inhibin/activin regulation of FSH.Developmen

The RESET project: constructing a European tephra lattice for refined synchronisation of environmental and archaeological events during the last c. 100 ka

This paper introduces the aims and scope of the RESET project (. RESponse of humans to abrupt Environmental Transitions), a programme of research funded by the Natural Environment Research Council (UK) between 2008 and 2013; it also provides the context and rationale for papers included in a special volume of Quaternary Science Reviews that report some of the project's findings. RESET examined the chronological and correlation methods employed to establish causal links between the timing of abrupt environmental transitions (AETs) on the one hand, and of human dispersal and development on the other, with a focus on the Middle and Upper Palaeolithic periods. The period of interest is the Last Glacial cycle and the early Holocene (c. 100-8 ka), during which time a number of pronounced AETs occurred. A long-running topic of debate is the degree to which human history in Europe and the Mediterranean region during the Palaeolithic was shaped by these AETs, but this has proved difficult to assess because of poor dating control. In an attempt to move the science forward, RESET examined the potential that tephra isochrons, and in particular non-visible ash layers (cryptotephras), might offer for synchronising palaeo-records with a greater degree of finesse. New tephrostratigraphical data generated by the project augment previously-established tephra frameworks for the region, and underpin a more evolved tephra 'lattice' that links palaeo-records between Greenland, the European mainland, sub-marine sequences in the Mediterranean and North Africa. The paper also outlines the significance of other contributions to this special volume: collectively, these illustrate how the lattice was constructed, how it links with cognate tephra research in Europe and elsewhere, and how the evidence of tephra isochrons is beginning to challenge long-held views about the impacts of environmental change on humans during the Palaeolithic. © 2015 Elsevier Ltd.RESET was funded through Consortium Grants awarded by the Natural Environment Research Council, UK, to a collaborating team drawn from four institutions: Royal Holloway University of London (grant reference NE/E015905/1), the Natural History Museum, London (NE/E015913/1), Oxford University (NE/E015670/1) and the University of Southampton, including the National Oceanography Centre (NE/01531X/1). The authors also wish to record their deep gratitude to four members of the scientific community who formed a consultative advisory panel during the lifetime of the RESET project: Professor Barbara Wohlfarth (Stockholm University), Professor Jørgen Peder Steffensen (Niels Bohr Institute, Copenhagen), Dr. Martin Street (Romisch-Germanisches Zentralmuseum, Neuwied) and Professor Clive Oppenheimer (Cambridge University). They provided excellent advice at key stages of the work, which we greatly valued. We also thank Jenny Kynaston (Geography Department, Royal Holloway) for construction of several of the figures in this paper, and Debbie Barrett (Elsevier) and Colin Murray Wallace (Editor-in-Chief, QSR) for their considerable assistance in the production of this special volume.Peer Reviewe

Rising rural body-mass index is the main driver of the global obesity epidemic in adults

Body-mass index (BMI) has increased steadily in most countries in parallel with a rise in the proportion of the population who live in cities 1,2 . This has led to a widely reported view that urbanization is one of the most important drivers of the global rise in obesity 3�6 . Here we use 2,009 population-based studies, with measurements of height and weight in more than 112 million adults, to report national, regional and global trends in mean BMI segregated by place of residence (a rural or urban area) from 1985 to 2017. We show that, contrary to the dominant paradigm, more than 55 of the global rise in mean BMI from 1985 to 2017�and more than 80 in some low- and middle-income regions�was due to increases in BMI in rural areas. This large contribution stems from the fact that, with the exception of women in sub-Saharan Africa, BMI is increasing at the same rate or faster in rural areas than in cities in low- and middle-income regions. These trends have in turn resulted in a closing�and in some countries reversal�of the gap in BMI between urban and rural areas in low- and middle-income countries, especially for women. In high-income and industrialized countries, we noted a persistently higher rural BMI, especially for women. There is an urgent need for an integrated approach to rural nutrition that enhances financial and physical access to healthy foods, to avoid replacing the rural undernutrition disadvantage in poor countries with a more general malnutrition disadvantage that entails excessive consumption of low-quality calories. © 2019, The Author(s)

Spatial and temporal expression of immunoglobulin superfamily member 1 in the rat

Diabetes mellitus: pathophysiological changes and therap

IGSF1 Deficiency: Lessons From an Extensive Case Series and Recommendations for Clinical Management

Clinical and biochemical characteristics of 69 male patients and 56 female IGSF1 mutation carriers were collected, providing recommendations for mutational analysis, endocrine work-up, and long-term car

The effects of various binders and moisture content on pellet stability of research diets for freshwater crayfish

Two experiments were conducted to assess the water stability of a practical research diet manufactured with various binders and differing levels of moisture. In the first experiment the binders &ndash; agar, gelatine, carrageenan, and carboxymethylcellulose (CMC) were included at both 3 and 5% of total ingredient weight. All binders were tested with equal ingredient weight to water volume, and additionally carrageenan was tested in a diet with double the water volume. The dry matter remaining following immersion for up to 180 min was calculated and the rate of pellet decay was modelled using the Weibull distribution. The analysis revealed that the rate of dry matter loss decreased with time, and that carrageenan and CMC binders were significantly better (P &lt; 0.001) binders than the agar and gelatine. The 5% binder concentration slowed the decay rate by as much as 62% as compared with the 3% binder concentration. The second experiment compared the binding performance of carrageenan and sodium alginate in both 50% moisture and 10% moisture pellets. The same analysis revealed that 10% moisture alginate-bound pellets were more water stable than the others. A discussion of the use of moist diets for crayfish research is included.<br /