Supraesophageal Reflux Disease: Solving a Riddle Wrapped in a Mystery Inside an Enigma

Copyright © 2015 AGA Institute. Published by Elsevier Inc. All rights reserved. This manuscript version is made available under the CC-BY-NC-ND 4.0 license http://creativecommons.org/licenses/by-nc-nd/4.0

Single-crystal growth and dependences on the hole concentration and magnetic field of the magnetic ground state in the edge-sharing CuO2_2 chain system Ca2+x_{2+x}Y2−x_{2-x}Cu5_5O10_{10}

We have succeeded in growing large-size single-crystals of Ca$_{2+x}$Y$_{2-x}$Cu$_5$O$_{10}$ with $0 \le x \le 1.67$ and measured the magnetic susceptibility, specific heat and magnetization curve, in order to study the magnetic ground state in the edge-sharing CuO$_2$ chain as a function of hole concentration and magnetic field. In $0 \le x \le 1.3$, it has been found that an antiferromagnetically ordered phase with the magnetic easy axis along the b-axis is stabilized and that a spin-flop transition occurs by the application of magnetic fields parallel to the b-axis. The antiferromagnetic transition temperature decreases with increasing $x$ and disappears around $x =$ 1.4. Alternatively, a spin-glass phase appears around $x = 1.5$. At $x = 1.67$ where the hole concentration is $\sim$ 1/3 per Cu, it appears that a spin-gap state is formed owing to the formation of spin-singlet pairs. No sign of the coexistence of an antiferromagnetically ordered state and a spin-gap one suggested in Ca$_{1-x}$CuO$_2$ has been found in Ca$_{2+x}$Y$_{2-x}$Cu$_5$O$_{10}$.Comment: 13 pages, 12 figures, 1 tabl

Moving walls accelerate mixing

Mixing in viscous fluids is challenging, but chaotic advection in principle allows efficient mixing. In the best possible scenario,the decay rate of the concentration profile of a passive scalar should be exponential in time. In practice, several authors have found that the no-slip boundary condition at the walls of a vessel can slow down mixing considerably, turning an exponential decay into a power law. This slowdown affects the whole mixing region, and not just the vicinity of the wall. The reason is that when the chaotic mixing region extends to the wall, a separatrix connects to it. The approach to the wall along that separatrix is polynomial in time and dominates the long-time decay. However, if the walls are moved or rotated, closed orbits appear, separated from the central mixing region by a hyperbolic fixed point with a homoclinic orbit. The long-time approach to the fixed point is exponential, so an overall exponential decay is recovered, albeit with a thin unmixed region near the wall.Comment: 17 pages, 13 figures. PDFLaTeX with RevTeX 4-1 styl

Esophageal impedance baselines in infants before and after placebo and proton pump inhibitor therapy

Author version made available in accordance with the publisher's policy.ABSTRACT Background Esophageal impedance monitoring records changes in conductivity. During esophageal rest impedance baseline values may represent mucosal integrity. The aim of this study was to assess the influence of acid suppression on impedance baselines in a placebo controlled setting. Material and Methods Impedance recordings from 40 infants (0-6months) enrolled in randomized placebo controlled trials of proton pump inhibitor (PPI) were retrospectively analyzed. Infants underwent 24hr pH-impedance monitoring prior to and after two weeks of double blind therapy with placebo or a PPI. Typical clinical signs of gastroesophageal reflux (GER) were recorded and I-GERQ-R questionnaire was completed. Key results Median (IQR) impedance baseline increased on PPI treatment (from 1217 (826-1514) to 1903 (1560-2194) Ohm, p<0.001) but not with placebo (from 1445 (1033-1791) to 1650 (1292-1983) Ohm, p=0.13). Baselines before treatment inversely correlate with the number of GER, acid GER, weakly acid GER, acid exposure and symptoms. The change in baseline on treatment inversely correlates with acid exposure and acid GER. Patients with initial low baselines have no improved symptomatic response to treatment. Conclusions and Inferences Impedance baselines are influenced by GER and increase significantly more with PPI therapy than with placebo. Clinical impact of this observation remains undefined as targeting therapy at infants with low baselines does not improve symptomatic response to treatment

Fostering bioscience innovation: lessons from BIO-EARN

This paper synthesises the findings of, and distils lessons from a study which has sought to illuminate the process of bioscience innovation in three East African countries: Kenya, Tanzania and Uganda. More specifically, we attempt to trace specific efforts to foster biotechnology innovations in those countries and to determine in what ways and to what extent the innovation system in place impinges on the final outcome of those innovations. The paper concludes with a set of policy recommendations that may enhance bioscience innovations in East Africa

Equilibrium and off-equilibrium simulations of the 4d Gaussian spin glass

In this paper we study the on and off-equilibrium properties of the four dimensional Gaussian spin glass. In the static case we determine with more precision that in previous simulations both the critical temperature as well as the critical exponents. In the off-equilibrium case we settle the general form of the autocorrelation function, and show that is possible to obtain dynamically, for the first time, a value for the order parameter.Comment: 16 pages and 13 figures, uses epsfig.sty and rotate.sty. Some minor grammatical changes. Also available at http://chimera.roma1.infn.it/index_papers_complex.htm

Static Critical Behavior of the Spin-Freezing Transition in the Geometrically Frustrated Pyrochlore Antiferromagnet Y2Mo2O7

Some frustrated pyrochlore antiferromagnets, such as Y2Mo2O7, show a spin-freezing transition and magnetic irreversibilities below a temperature Tf similar to what is observed nonlinear magnetization measurements on Y2Mo2O7 that provide strong evidence that there is an underlying thermodynamic phase transition at Tf, which is characterized by critical exponents \gamma \approx 2.8 and \beta \approx 0.8. These values are typical of those found in random spin glasses, despite the fact that the level of random disorder in Y2Mo2O7 is immeasurably small.Comment: Latex file, calls for 4 encapsulated postscript figures (included). Submitted to Phys. Rev. Letters

Nutrition knowledge and food consumption practices and barriers in rural Ghana: The case of foods for preventing vitamin A and iron deficiencies

Food-based approaches such as dietary diversification, nutrient retention and biofortification combined with nutrition education can be effective in eliminating micronutrient deficiencies. The objective of this study was to assess the nutrition knowledge and consumption practices as well as barriers to consumption with specific focus on food-based approaches to vitamin A and iron deficiencies prevention and to identify individual, community and governmental level strategies that may facilitate the adoption of these approaches. Using qualitative methods, one focus group (FG) discussion each was conducted with members of the Cocoa Farmers’ Cooperatives in each of the 25 rural communities in the Amansie West and Asunafo North Districts in Ghana. Findings showed participants in only 3 FGs had knowledge of vitamin A and its deficiency diseases while only 2 FGs had knowledge of foods that could prevent vitamin A deficiency. Participants in 23 FGs were aware of the occurrence of iron deficiency anaemia especially in pregnant women; however, only 8 FGs had knowledge of the causes of anaemia. Furthermore, all the 25 FGs mentioned the use of haematinics in the treatment and prevention of anaemia but only 4 FGs knew about the use of food-based approaches. Various types of animal products, vegetables, fruits, and legumes, which are useful in preventing vitamin A and iron deficiencies, were found to be available in the communities. However, participants in all the 25 FGs indicated that the consumption of these foods particularly dark-green leafy vegetables has been dwindling with time. The FG participants mentioned a number of barriers to consumption of these foods and they include inadequate knowledge of nutritional value of the foods, lack of cooking skill, low production levels, laziness, conflicting media reports, lack of storage facilities, and contamination with agrochemicals. Findings imply that nutrition interventions should focus on education and awareness creation and implementation of strategies that can remove consumption barriers and facilitate the adoption of food-based approaches for managing micronutrient deficiencies.Key words: Vitamin A deficiency, iron deficiency, nutrition knowledge, consumption practices, barrier