1,007 research outputs found

    Modeling of Nitrous Oxide Production from Nitritation Reactors Treating Real Anaerobic Digestion Liquor.

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    In this work, a mathematical model including both ammonium oxidizing bacteria (AOB) and heterotrophic bacteria (HB) is constructed to predict N2O production from the nitritation systems receiving the real anaerobic digestion liquor. This is for the first time that N2O production from such systems was modeled considering both AOB and HB. The model was calibrated and validated using experimental data from both lab- and pilot-scale nitritation reactors. The model predictions matched the dynamic N2O, ammonium, nitrite and chemical oxygen demand data well, supporting the capability of the model. Modeling results indicated that HB are the dominant contributor to N2O production in the above systems with the dissolved oxygen (DO) concentration of 0.5-1.0 mg O2/L, accounting for approximately 75% of N2O production. The modeling results also suggested that the contribution of HB to N2O production decreased with the increasing DO concentrations, from 75% at DO = 0.5 mg O2/L to 25% at DO = 7.0 mg O2/L, with a corresponding increase of the AOB contribution (from 25% to 75%). Similar to HB, the total N2O production rate also decreased dramatically from 0.65 to 0.25 mg N/L/h when DO concentration increased from 0.5 to 7.0 mg O2/L

    Dirac-harmonic maps from index theory

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    We prove existence results for Dirac-harmonic maps using index theoretical tools. They are mainly interesting if the source manifold has dimension 1 or 2 modulo 8. Our solutions are uncoupled in the sense that the underlying map between the source and target manifolds is a harmonic map.Comment: 26 pages, no figur

    Z^* Resonances: Phenomenology and Models

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    We explore the phenomenology of, and models for, the Z^* resonances, the lowest of which is now well established, and called the Theta. We provide an overview of three models which have been proposed to explain its existence and/or its small width, and point out other relevant predictions, and potential problems, for each. The relation to what is known about KN scattering, including possible resonance signals in other channels, is also discussed.Comment: 29 pages, uses RevTeX4; expanded version (published form

    New insights into ion regulation of cephalopod molluscs: a role of epidermal ionocytes in acid-base regulation during embryogenesis

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    The constraints of an active life in a pelagic habitat led to numerous convergent morphological and physiological adaptations that enable cephalopod molluscs and teleost fishes to compete for similar resources. Here we show for the first time that such convergent developments are also found in the ontogenetic progression of ion regulatory tissues: as in teleost fish epidermal ionocytes scattered on skin and yolk sac of cephalopod embryos appear to be responsible for ionic and acid-base regulation before gill epithelia become functional. Ion and acid-base regulation is crucial in cephalopod embryos, as they are surrounded by a hypercapnic egg fluid with a pCO2 of 0.2-0.4 kPa. Epidermal ionocytes were characterized via immunohistochemistry, in situ hybridization and vital dye staining techniques. We found one group of cells that is recognized by Concavalin A and MitoTracker, which also expresses Na+/H+ exchangers (NHE) and Na+/K+-ATPase. Similar to findings obtained in teleosts these NHE3-rich cells take up sodium in exchange for protons, illustrating the energetic superiority of NHE based proton excretion in marine systems. In vivo electrophysiological techniques demonstrated that acid equivalents are secreted by the yolk and skin integument. Intriguingly, epidermal ionocytes of cephalopod embryos are ciliated as demonstrated by scanning electron microscopy suggesting a dual function of epithelial cells in water convection and ion regulation. These findings add significant knowledge to our mechanistic understanding of hypercapnia tolerance in marine organisms, as it demonstrates that marine taxa which were identified as powerful acid-base regulators during hypercapnic challenges already exhibit strong acid-base regulatory abilities during embryogenesis

    Disparity in Reimbursement for Tuberculosis Care Among Different Health Insurance Schemes: Evidence from Three Counties in Central China

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    Background: Health inequity is an important issue all around the world. The Chinese basic medical security system comprises three major insurance schemes, namely the Urban Employee Basic Medical Insurance (UEBMI), the Urban Resident Basic Medical Insurance (URBMI), and the New Cooperative Medical Scheme (NCMS). Little research has been conducted to look into the disparity in payments among the health insurance schemes in China. In this study, we aimed to evaluate the disparity in reimbursements for tuberculosis (TB) care among the abovementioned health insurance schemes. Methods: This study uses a World Health Organization (WHO) framework to analyze the disparities and equity relating to the three dimensions of health insurance: population coverage, the range of services covered, and the extent to which costs are covered. Each of the health insurance scheme’s policies were categorized and analyzed. An analysis of the claims database of all hospitalizations reimbursed from 2010 to 2012 in three counties of Yichang city (YC), which included 1506 discharges, was conducted to identify the differences in reimbursement rates and out-of-pocket (OOP) expenses among the health insurance schemes. Results: Tuberculosis patients had various inpatient expenses depending on which scheme they were covered by (TB patients covered by the NCMS have less inpatient expenses than those who were covered by the URBMI, who have less inpatient expenses than those covered by the UEBMI). We found a significant horizontal inequity of healthcare utilization among the lower socioeconomic groups. In terms of financial inequity, TB patients who earned less paid more. The NCMS provides modest financial protection, based on income. Overall, TB patients from lower socioeconomic groups were the most vulnerable. Conclusion: There are large disparities in reimbursement for TB care among the three health insurance schemes and this, in turn, hampers TB control. Reducing the gap in health outcomes between the three health insurance schemes in China should be a focus of TB care and control. Achieving equity through integrated policies that avoid discrimination is likely to be effective

    Identification of Hypoxia-Regulated Proteins Using MALDI-Mass Spectrometry Imaging Combined with Quantitative Proteomics

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    Hypoxia is present in most solid tumors and is clinically correlated with increased metastasis and poor patient survival. While studies have demonstrated the role of hypoxia and hypoxia-regulated proteins in cancer progression, no attempts have been made to identify hypoxia-regulated proteins using quantitative proteomics combined with MALDI-mass spectrometry imaging (MALDI-MSI). Here we present a comprehensive hypoxic proteome study and are the first to investigate changes in situ using tumor samples. In vitro quantitative mass spectrometry analysis of the hypoxic proteome was performed on breast cancer cells using stable isotope labeling with amino acids in cell culture (SILAC). MS analyses were performed on laser-capture microdissected samples isolated from normoxic and hypoxic regions from tumors derived from the same cells used in vitro. MALDI-MSI was used in combination to investigate hypoxia-regulated protein localization within tumor sections. Here we identified more than 100 proteins, both novel and previously reported, that were associated with hypoxia. Several proteins were localized in hypoxic regions, as identified by MALDI-MSI. Visualization and data extrapolation methods for the in vitro SILAC data were also developed, and computational mapping of MALDI-MSI data to IHC results was applied for data validation. The results and limitations of the methodologies described are discussed. 2014 American Chemical Societ

    Search for the glueball candidates f0(1500) and fJ(1710) in gamma gamma collisions

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    Data taken with the ALEPH detector at LEP1 have been used to search for gamma gamma production of the glueball candidates f0(1500) and fJ(1710) via their decay to pi+pi-. No signal is observed and upper limits to the product of gamma gamma width and pi+pi- branching ratio of the f0(1500) and the fJ(1710) have been measured to be Gamma_(gamma gamma -> f0(1500)). BR(f0(1500)->pi+pi-) < 0.31 keV and Gamma_(gamma gamma -> fJ(1710)). BR(fJ(1710)->pi+pi-) < 0.55 keV at 95% confidence level.Comment: 10 pages, 3 figure

    Search for supersymmetry with a dominant R-parity violating LQDbar couplings in e+e- collisions at centre-of-mass energies of 130GeV to 172 GeV

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    A search for pair-production of supersymmetric particles under the assumption that R-parity is violated via a dominant LQDbar coupling has been performed using the data collected by ALEPH at centre-of-mass energies of 130-172 GeV. The observed candidate events in the data are in agreement with the Standard Model expectation. This result is translated into lower limits on the masses of charginos, neutralinos, sleptons, sneutrinos and squarks. For instance, for m_0=500 GeV/c^2 and tan(beta)=sqrt(2) charginos with masses smaller than 81 GeV/c^2 and neutralinos with masses smaller than 29 GeV/c^2 are excluded at the 95% confidence level for any generation structure of the LQDbar coupling.Comment: 32 pages, 30 figure

    Search for CP Violation in the Decay Z -> b (b bar) g

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    About three million hadronic decays of the Z collected by ALEPH in the years 1991-1994 are used to search for anomalous CP violation beyond the Standard Model in the decay Z -> b \bar{b} g. The study is performed by analyzing angular correlations between the two quarks and the gluon in three-jet events and by measuring the differential two-jet rate. No signal of CP violation is found. For the combinations of anomalous CP violating couplings, h^b=h^AbgVbh^VbgAb{\hat{h}}_b = {\hat{h}}_{Ab}g_{Vb}-{\hat{h}}_{Vb}g_{Ab} and hb=h^Vb2+h^Ab2h^{\ast}_b = \sqrt{\hat{h}_{Vb}^{2}+\hat{h}_{Ab}^{2}}, limits of \hat{h}_b < 0.59and and h^{\ast}_{b} < 3.02$ are given at 95\% CL.Comment: 8 pages, 1 postscript figure, uses here.sty, epsfig.st

    Search for the standard model Higgs boson at LEP

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