Intestinal absorption barriers as modelled by p-glycoprotein and cytochrome p450 a34 in caco2 cells

The passage number and origin of two populations of Caco-2 cells influence their enterocyte-like characteristics. Caco-2 cells of passage number >90 from Novartis pharmaceutical company possess higher levels of expression of alkaline phosphatase and P-glycoprotein and a greater cellular uptake of Gly-1.-Pro than those of passage number <40 from the American Type Tissue Culture collection. High P-gp expressing Caco-2 cells have been developed through stepwise selection of the cells with doxonibicin. This newly-developed cell line (hereafter referred to as Type I) possesses approximately twice as much P-gp protein than non-exposed cells, restricts the transepithelial transport of vincristine in the apical-to-basolateral direction whilst facilitating its transport in the reverse direction and accumulates less vincristine than non-exposed cells. There is no apparent evidence of the co-existence of the multidrug resistance protein (MIT) in Type I cells to account for the above-listed observations. Stopping the exposure for more than 28 days decreases the P-gp protein expression in previously doxorubicin-exposed Type I Caco-2 cells and reduces the magnitude of vincristine transepithelial fluxes in both directions to the levels that are almost similar to those of non-exposed cells. Exposing Caco-2 cells to 0.25 JAM la, 25-dihydroxyvitamin D3 induces their expression of cytochrome P450 3A4 protein to the level that is equivalent to that from isolated human jejunal cells. Under the same treatment, doxorubiein-exposed (Type I) cells metabolise naidazolam poorly and less extensively compared to non-exposed cells, suggesting that there is no such co-regulation of P-gp and CYP3A4 in Caco-2 cells. However, there is evidence which suggests CYP3A metabolises mida_zolam into 1- and 4-hydroxymidazolam, the latter may possibly be a P-gp substrate and is transported extracellularly by P-gp, supporting the hypothesis of P-gp-CYP3A4 synergistic roles in keeping xenobiotics out of the body. Doxoru.bicin-exposed (Type I) cells are less effective in translocating L-proline and glycyl-L-proline across the cell mono layers

The application of coupled finite-discrete element method in analyzing soil-structure interaction problems

A framework to couple the Finite and the Discrete element methods is proposed in this study. The framework takes advantage of both approaches to investigate different soilstructure interaction problems. The structural elements in the problems are modeled using finite elements whereas surrounding soil is modeled using discrete elements to reflect the discontinuous nature of the granular material. The coupled framework is then used to model three soil-geogrid interaction problems including geogrid pullout test, strip footing on geogrid-reinforced sand and geogrid reinforced fill over void. The numerical results show the efficiency of the coupled framework to model the interlocking effect between the soil and the geogrid sheet. New insights into the nature of the interaction between the soil and the geogrid at the microscopic scale are also presented

CupMar: A deep learning model for personalized news recommendation based on contextual user-profile and multi-aspect article representation

OnlinePublIn modern days, making recommendation for news articles poses a great challenge due to vast amount of online information. However, providing personalized recommendations from news articles, which are the sources of condense textual information is not a trivial task. A recommendation system needs to understand both the textual information of a news article, and the user contexts in terms of long-term and temporary preferences via the user’s historic records. Unfortunately, many existing methods do not possess the capability to meet such need. In this work, we propose a neural deep news recommendation model called CupMar, that not only is able to learn the user-profile representation in different contexts, but also is able to leverage the multi-aspects properties of a news article to provide accurate, personalized news recommendations to users. The main components of our CupMar approach include the News Encoder and the User-Profile Encoder. Specifically, the News Encoder uses multiple properties such as news category, knowledge entity, title and body content with advanced neural network layers to derive informative news representation, while the User-Profile Encoder looks through a user’s browsed news, infers both of her long-term and recent preference contexts to encode a user representation, and finds the most relevant candidate news for her. We evaluate our CupMar model with extensive experiments on the popular Microsoft News Dataset (MIND), and demonstrate the strong performance of our approach.Dai Hoang Tran, Quan Z. Sheng, Wei Emma Zhang, Nguyen H. Tran, Nguyen Lu Dang Kho

Market risk analysis of energy in Vietnam

The purpose of this paper is to evaluate and estimate market risk for the ten major industries in Vietnam. The focus of the empirical analysis is on the energy sector, which has been designated as one of the four key industries, together with services, food, and telecommunications, targeted for economic development by the Vietnam Government through to 2020. The oil and gas industry is a separate energy-related major industry, and it is evaluated separately from energy. The data set is from 2009 to 2017, which is decomposed into two distinct sub-periods after the Global Financial Crisis (GFC), namely the immediate post-GFC (2009–2011) period and the normal (2012–2017) period, in order to identify the behavior of market risk for Vietnam’s major industries. For the stock market in Vietnam, the website used in this paper provided complete and detailed data for each stock, as classified by industry. Two widely used approaches to measure and analyze risk are used in the empirical analysis, namely Value-at-Risk (VaR) and Conditional Value-at-Risk (CVaR). The empirical findings indicate that Energy and Pharmaceuticals are the least risky industries, whereas oil and gas and securities have the greatest risk. In general, there is strong empirical evidence that the four key industries display relatively low risk. For public policy, the Vietnam Government’s proactive emphasis on the targeted industries, including energy, to achieve sustainable economic growth and national economic development, seems to be working effectively. This paper presents striking empirical evidence that Vietnam’s industries have substantially improved their economic performance over the full sample, moving from relatively higher levels of market risk in the immediate post-GFC period to a lower risk environment in a normal period several years after the end of the calamitous GFC

Rate-equation calculations of the current flow through two-site molecular device and DNA-based junction

Here we present the calculations of incoherent current flowing through the two-site molecular device as well as the DNA-based junction within the rate-equation approach. Few interesting phenomena are discussed in detail. Structural asymmetry of two-site molecule results in rectification effect, which can be neutralized by asymmetric voltage drop at the molecule-metal contacts due to coupling asymmetry. The results received for poly(dG)-poly(dC) DNA molecule reveal the coupling- and temperature-independent saturation effect of the current at high voltages, where for short chains we establish the inverse square distance dependence. Besides, we document the shift of the conductance peak in the direction to higher voltages due to the temperature decrease.Comment: 12 pages, 6 figure

Soil fertility regulates invasive herbivore performance and top-down control in tropical agroecosystems of Southeast Asia

In terrestrial ecosystems, changes in soil nutrient availability, plant growth or natural enemies can generate important shifts in abundance of organisms at various trophic levels. In agroecosystems the performance of (invasive) herbivores and their impacts on crops is of particular concern. Scientists are presently challenged with making reliable inferences on invader success, natural enemy performance and efficacy of biological control, particularly in tropical agroecosystems. In this study, we assess how trophic regulatory forces (bottom-up vs. top down) influence the success of three globally important pests of cassava. We examine the mealybug species (Hemiptera: Pseudococcidae) of differing host breadth and invasion history: Phenacoccus manihoti, Paracoccus marginatus, and Pseudococcus jackbeardsleyi. Potted plant fertilizer trials were combined with a regional survey in Vietnam, Laos and Cambodia of 65 cassava fields of similar size and age, but with varying soil fertility. Relative abundance of each mealybug invader was mapped along a soil fertility gradient, and contrasted with site-specific measures of parasitism. Potted plant trials revealed strong bottom-up effects for P. manihoti, such that impacts of nitrogen and potassium additions were propagated through to higher trophic levels and substantially boost development and fitness of its specialist parasitoid, Anagyrus lopezi (Hymenoptera: Encyrtidae). Field surveys indicate that mealybug performance is highly species-specific and context-dependent. For example, field-level abundance of P. jackbeardsleyi and P. marginatus, was related to measures of soil fertility parameters, soil texture and plant disease incidence. Furthermore, for P. manihoti, in-field abundance is equally associated with soil texture (i.e., silt content). Principal component analysis (PCA) and regression suggested that P. manihoti and P. marginatus are disproportionately favored in low-fertility conditions, while P. jackbeardsleyi prospers in settings with high organic carbon and phosphorus. Parasitism of P. manihoti by A. lopezi varied greatly with field and soil fertility conditions, and was highest in soils with intermediate fertility levels and where management practices include the addition of fertilizer supplements. Our characterization of the relative performance of invasive mealybugs and strength of parasitism across variable soil fertility conditions will help guide parasitoid release programs and soil management practices that enhance mealybug biological control

Search for R-Parity Violating Decays of Scalar Fermions at LEP

A search for pair-produced scalar fermions under the assumption that R-parity is not conserved has been performed using data collected with the OPAL detector at LEP. The data samples analysed correspond to an integrated luminosity of about 610 pb-1 collected at centre-of-mass energies of sqrt(s) 189-209 GeV. An important consequence of R-parity violation is that the lightest supersymmetric particle is expected to be unstable. Searches of R-parity violating decays of charged sleptons, sneutrinos and squarks have been performed under the assumptions that the lightest supersymmetric particle decays promptly and that only one of the R-parity violating couplings is dominant for each of the decay modes considered. Such processes would yield final states consisting of leptons, jets, or both with or without missing energy. No significant single-like excess of events has been observed with respect to the Standard Model expectations. Limits on the production cross- section of scalar fermions in R-parity violating scenarios are obtained. Constraints on the supersymmetric particle masses are also presented in an R-parity violating framework analogous to the Constrained Minimal Supersymmetric Standard Model.Comment: 51 pages, 24 figures, Submitted to Eur. Phys. J.

Measurement of the Hadronic Photon Structure Function F_2^gamma at LEP2

The hadronic structure function of the photon F_2^gamma is measured as a function of Bjorken x and of the factorisation scale Q^2 using data taken by the OPAL detector at LEP. Previous OPAL measurements of the x dependence of F_2^gamma are extended to an average Q^2 of 767 GeV^2. The Q^2 evolution of F_2^gamma is studied for average Q^2 between 11.9 and 1051 GeV^2. As predicted by QCD, the data show positive scaling violations in F_2^gamma. Several parameterisations of F_2^gamma are in agreement with the measurements whereas the quark-parton model prediction fails to describe the data.Comment: 4 pages, 2 figures, to appear in the proceedings of Photon 2001, Ascona, Switzerlan

Search for a W' boson decaying to a bottom quark and a top quark in pp collisions at sqrt(s) = 7 TeV

Results are presented from a search for a W' boson using a dataset corresponding to 5.0 inverse femtobarns of integrated luminosity collected during 2011 by the CMS experiment at the LHC in pp collisions at sqrt(s)=7 TeV. The W' boson is modeled as a heavy W boson, but different scenarios for the couplings to fermions are considered, involving both left-handed and right-handed chiral projections of the fermions, as well as an arbitrary mixture of the two. The search is performed in the decay channel W' to t b, leading to a final state signature with a single lepton (e, mu), missing transverse energy, and jets, at least one of which is tagged as a b-jet. A W' boson that couples to fermions with the same coupling constant as the W, but to the right-handed rather than left-handed chiral projections, is excluded for masses below 1.85 TeV at the 95% confidence level. For the first time using LHC data, constraints on the W' gauge coupling for a set of left- and right-handed coupling combinations have been placed. These results represent a significant improvement over previously published limits.Comment: Submitted to Physics Letters B. Replaced with version publishe