2,189 research outputs found

    The Contribution of Population Health and Demographic Change to Economic Growth in China and India

    Get PDF
    We find that a cross-country model of economic growth successfully tracks the growth takeoffs in China and India. The major drivers of the predicted takeoffs are improved health, increased openness to trade, and a rising labor force-to-population ratio due to fertility decline. We also explore the effect of the reallocation of labor from low-productivity agriculture to the higher productivity industry and service sectors. Including the money value of longevity improvements in a measure of full income reduces the gap between the magnitude of China's takeoff relative to India's due to the relative stagnation in life expectancy in China since 1980.aging, health, retirement

    Molecular Characterization of the 14-3-3 Gene Family in Brachypodium distachyon L. Reveals High Evolutionary Conservation and Diverse Responses to Abiotic Stresses

    Get PDF
    The 14-3-3 gene family identified in all eukaryotic organisms is involved in a wide range of biological processes, particularly in resistance to various abiotic stresses. Here, we performed the first comprehensive study on the molecular characterisation, phylogenetics and responses to various abiotic stresses of the 14-3-3 gene family in Brachypodium distachyon L.. A total of seven 14-3-3 genes from B. distachyon and 120 from five main lineages among 12 species were identified, which were divided into five well-conserved subfamilies. The molecular structure analysis showed that the plant 14-3-3 gene family is highly evolutionarily conserved, although certain divergence had occurred in different subfamilies. The duplication event investigation revealed that segmental duplication seemed to be the predominant form by which the 14-3-3 gene family had expanded. Moreover, seven critical amino acids were detected, which may contribute to functional divergence. Expression profiling analysis showed that BdGF14 genes were abundantly expressed in the roots, but showed low expression in the meristems. All seven BdGF14 genes showed significant expression changes under various abiotic stresses, including heavy metal, phytohormone, osmotic, and temperature stresses, which might play important roles in responses to multiple abiotic stresses mainly through participating in ABA-dependent signalling and reactive oxygen species-mediated MAPK cascade signalling pathways. In particular, BdGF14 genes generally showed upregulated expression in response to multiple stresses of high temperature, heavy metal, abscisic acid (ABA), and salicylic acid (SA), but downregulated expression under H2O2, NaCl, and polyethylene glycol (PEG) stresses. Meanwhile, dynamic transcriptional expression analysis of BdGF14 genes under longer treatments with heavy metals (Cd2+, Cr3+, Cu2+, and Zn2+) and phytohormone (ABA) and recovery revealed two main expression trends in both roots and leaves: up-down and up-down-up expression from stress treatments to recovery. This study provides new insights into the structures and functions of plant 14-3-3 genes

    A novel hybrid technique for short-term electricity price forecasting in deregulated electricity markets

    Get PDF
    This thesis was submitted for the degree of Doctor of Philosophy and awarded by Brunel University.Short-term electricity price forecasting is now crucial practice in deregulated electricity markets, as it forms the basis for maximizing the profits of the market participants. In this thesis, short-term electricity prices are forecast using three different predictor schemes, Artificial Neural Networks (ANNs), Support Vector Machine (SVM) and a hybrid scheme, respectively. ANNs are the very popular and successful tools for practical forecasting. In this thesis, a hidden-layered feed-forward neural network with back-propagation has been adopted for detailed comparison with other forecasting models. SVM is a newly developed technique that has many attractive features and good performance in terms of prediction. In order to overcome the limitations of individual forecasting models, a hybrid technique that combines Fuzzy-C-Means (FCM) clustering and SVM regression algorithms is proposed to forecast the half-hour electricity prices in the UK electricity markets. According to the value of their power prices, thousands of the training data are classified by the unsupervised learning method of FCM clustering. SVM regression model is then applied to each cluster by taking advantage of the aggregated data information, which reduces the noise for each training program. In order to demonstrate the predictive capability of the proposed model, ANNs and SVM models are presented and compared with the hybrid technique based on the same training and testing data sets in the case studies by using real electricity market data. The data was obtained upon request from APX Power UK for the year 2007. Mean Absolute Percentage Error (MAPE) is used to analyze the forecasting errors of different models and the results presented clearly show that the proposed hybrid technique considerably improves the electricity price forecasting

    Isolation and analysis of a very virulent Marek’s disease virus strain in China

    Get PDF
    BACKGROUND: A severe MD was broken out at a farm in Shandong, China, despite FC126 vaccination of the chickens at 1-day-old. The mortality of the flocks reached up to 38.3%. The infected chickens were found to have MD pathological changes, including enlargement of spleens, livers and kidneys, and tumors occured on organs later. Samples were collected from the chickens for diagnosis. METHODS: The collected samples were inoculated into primary duck embryo fibroblast (DEF) cells, and the MDV strain named SD2012-1 was isolated. In order to identify the isolate, amplification by PCR and sequencing of oncogenic Meq and vIL-8 gene were processed, the obtained sequences were compared with the sequences of reference strains, and SD2012-1 was used to challenge immunized SPF chickens. RESULTS: A very virulent MDV isolate strain, SD2012-1, was isolated from a chicken flock in Shandong Province, China, the isolate had the characteristics of very virulent MDV-1, nucleotide and deduced amino acid sequence comparisons of Meq and vIL-8 gene of SD2012-1 with those of reference strains showed SD2012-1 had high homology with MDV strains isolated from China, SD2012-1 could break through the protection provided by HVT vaccine and HVT + SB-1 vaccine immunization and caused the mortality of SPF chickens over 60%. The immune failure occured at the farm could be due to the improper selection of vaccines. SD2012-1 produced death later and the gross postmortem lesions of chickens died early and later were different. CONCLUSIONS: MDV strain SD2012-1 isolated from Shandong Province, China was found to have the characteristics of very virulent MDV-1, which could break through the protection provided by HVT vaccine and HVT + SB-1 vaccine, the virus seemed to have a long latent period, and cause different gross postmortem lesions of chickens between chickens died early and later. A better immunization way should be chosen to prevent infection of this MDV strain in field

    The Galactic extinction and reddening from the South Galactic Cap U-band Sky Survey: u band galaxy number counts and uru-r color distribution

    Full text link
    We study the integral Galactic extinction and reddening based on the galaxy catalog of the South Galactic Cap U-band Sky Survey (SCUSS), where uu band galaxy number counts and uru-r color distribution are used to derive the Galactic extinction and reddening respectively. We compare these independent statistical measurements with the reddening map of \citet{Schlegel1998}(SFD) and find that both the extinction and reddening from the number counts and color distribution are in good agreement with the SFD results at low extinction regions (E(BV)SFD<0.12E(B-V)^{SFD}<0.12 mag). However, for high extinction regions (E(BV)SFD>0.12E(B-V)^{SFD}>0.12 mag), the SFD map overestimates the Galactic reddening systematically, which can be approximated by a linear relation ΔE(BV)=0.43[E(BV)SFD0.12\Delta E(B-V)= 0.43[E(B-V)^{SFD}-0.12]. By combing the results of galaxy number counts and color distribution together, we find that the shape of the Galactic extinction curve is in good agreement with the standard RV=3.1R_V=3.1 extinction law of \cite{ODonnell1994}

    Well-posedness of grating diffraction problems for plane wave incidence: explicit dependence on wavenumbers and incident angles

    Full text link
    Suppose that a plane wave is incident onto an impenetrable grating profile of Dirichlet or Impedance type or a penetrable grating. The grating interface is assumed to be given by a Lipschitz function in two dimensions. We derive stability estimate of the grating diffraction problem via variational method with an explicit dependence of solutions on the incident wavenumber and incident angle

    Finite element and integral equation methods to conical diffraction by imperfectly conducting gratings

    Full text link
    In this paper we study the variational method and integral equation methods for a conical diffraction problem for imperfectly conducting gratings modeled by the impedance boundary value problem of the Helmholtz equation in periodic structures. We justify the strong ellipticity of the sesquilinear form corresponding to the variational formulation and prove the uniqueness of solutions at any frequency. Convergence of the finite element method using the transparent boundary condition (Dirichlet-to-Neumann mapping) is verified. The boundary integral equation method is also discussed

    Hypaconitine confers protection on ketamine-induced neuronal injury in neonatal rat brain via a mechanism involving PI3K/Akt/Bcl-2 pathway

    Get PDF
    Purpose: To investigate the neuroprotective effect of hypaconitine against ketamine-induced neuronal injury in the brains of neonatal rats, and the underlying mechanism of action. Methods: Seven day-old Sprague-Dawley pups weighing 15.0 to 20.0 g (mean weight = 17.5 ± 2.5 g), and aged 7 days were used for this study. The pups were sacrificed, and their forebrains isolated and used to prepare cell suspensions. The isolated cells were treated with ketamine (100 µM) or varied concentrations of hypaconitine (0.1 – 2 µM) or LY294002 (10 µM). The cells were trypsinized and cultured at 37 °C in 10 % fetal bovine serum (FBS) supplemented Dulbecco's modified Eagle's medium (DMEM) in a humidified incubator containing 5 % CO2. Cell viability was determined using MTT assay, while TUNEL assay was used to determine the extent of apoptosis in the cells. The expressions of pAkt, Bcl-2 and caspase-3 were determined using Western blotting. Results: There were only few viable cells in the ketamine-treated group, and cell viability was significantly and dose-dependently increased in hypaconitine-treated groups (p &lt; 0.05). The extent of apoptosis was significantly higher in ketamine-treated cells than in control cells, but treatment with hypaconitine significantly reduced the number of apoptotic cells (p &lt; 0.05). However, in the presence of LY294002 (a PI3K-specific inhibitor), the effect of hypaconitine on neuronal cell apoptosis was significantly reversed (p &lt; 0.05). The expressions of p-Akt and Bcl-2 were significantly down-regulated while the expression of caspase-3 was significantly upregulated in ketamine-treated neuronal cells, when compared with control group (p &lt; 0.05). However, in cells treated with hypaconitine, the expressions of p-Akt and Bcl-2 were significantly upregulated, while the expression of caspase-3 was significantly down-regulated (p &lt; 0.05). Treatment of neuronal cells with hypaconitine in the presence of LY294002 significantly reversed the effect of hypaconitine on the expressions of p-Akt, Bcl-2 and caspase-3 (p &lt; 0.05). Conclusion: These results suggest that hypaconitine ameliorates ketamine-induced neuronal injury in neonatal rats via a mechanism involving the PI3K/Akt/Bcl-2 pathway

    Securitization and Bank Credit Risk: Empirical Evidence from the US Commercial Banks

    Get PDF
    The main objective of this dissertation is to empirically analysis the effect of securitization activities on bank risks, and the influence of other bank specific factors are also considered simultaneously. Additionally, this analysis further examines the relationship between securitization activities and long-term bank stability. The sample data selected to make analysis is the balanced data of 149 US commercial banks from 2007 to 2017, which could represent both 2007-2009 Financial Crisis period and post-crisis period. In particular, we employ panel data approach to make correlation estimation by pooled OLS method, fixed effect model and random model. From test results, we find that securitization has a significant positive effect on bank credit risk level while negatively influence bank long-term stability. That is, the more securitized assets owned by banks, the bank would be riskier and more erratic
    corecore