Inspired by the success of BESDIRAC, the distributed computing environment based on DIRAC for BESIII experiment, several other experiments operated by Institute of High Energy Physics (IHEP), such as ...Circular Electron Positron Collider (CEPC), Jiangmen Underground Neutrino Observatory (JUNO), Large High Altitude Air Shower Observatory (LHAASO) and Hard X-ray Modulation Telescope (HXMT) etc, are willing to use DIRAC to integrate the geographically distributed computing resources available by their collaborations. In order to minimize manpower and hardware cost, we extended the BESDIRAC platform to support multi-VO scenario, instead of setting up a self-contained distributed computing environment for each VO. This makes DIRAC as a service for the community of those experiments. To support multi-VO, the system architecture of BESDIRAC is adjusted for scalability. The VOMS and DIRAC servers are reconfigured to manage users and groups belong to several VOs. A lightweight storage resource manager StoRM is employed as the central SE to integrate local and grid data. A frontend system is designed for user's massive job splitting, submission and management, with plugins to support new VOs. A monitoring and accounting system is also considered to easy the system administration and VO related resources usage accounting.
Distributed computing is necessary nowadays for high energy physics experiments to organize heterogeneous computing resources all over the world to process enormous amounts of data. The BESIII ...experiment in China, has established its own distributed computing system, based on DIRAC, as a supplement to local clusters, collecting cluster, grid, desktop and cloud resources from collaborating member institutes around the world. The system consists of workload management and data management to deal with the BESIII Monte Carlo production workflow in a distributed environment. A dataset-based data transfer system has been developed to support data movements among sites. File and metadata management tools and a job submission frontend have been developed to provide a virtual layer for BESIII physicists to use distributed resources. Moreover, the paper shows the experience to cope with lack of grid experience and low manpower among the BESIII community.
24 surface sediment samples were collected from the Bering Sea, Chukchi Sea, and Canada Basin during the 3rd Chinese National Arctic Research Expedition in July–September 2008. To obtain information ...on the levels, spatial distribution, possible sources, and influences of total carbon and black carbon, we analyzed the samples for polybrominated diphenyl ethers (PBDEs) and decabromodiphenylethane (DBDPE). Concentrations of ∑PBDEs (hereafter, ∑PBDEs refers to the sum of all detected PBDE congeners without BDE-209), BDE-209, and DBDPE were in the ranges 3.58–148.95pg/g d.w. (dry weight), n.d. −804.91pg/g d.w. and n.d. −452.57pg/g d.w., respectively. The congener patterns of PBDEs suggested that BDE-209 was the major congener in these areas, followed by BDE-99 and −47, which was consistent with the predominance of technical deca-BDE mixtures in the dominant technical PBDE mixtures. The significant relationships of BDE-209, -47, and -99 and total PBDEs with total organic carbon and black carbon, as well as the skewed distribution of ∑PBDEs and BDE-209, indicated that atmospheric deposition and local discharge might be potential sources in this area, and the distribution pattern may be the combined effect of multiple factors.
The Drosophila gypsy retrotransposon disrupts gene activity by blocking the interactions of distal enhancers with target promoters. This enhancer-blocking activity is mediated by a 340 bp insulator ...DNA within gypsy. The insulator contains a cluster of binding sites for a zinc finger protein, suppressor of Hairy wing su(Hw). Recent studies have shown that a second protein, mod(mdg4), is also important for normal insulator function. Mutations in mod(mdg4) exert paradoxical effects on different gypsy-induced phenotypes. For example, it enhances yellow(2) but suppresses cut(6). Here, we employ a stripe expression assay in transgenic embryos to investigate the role of mod(mdg4) in gypsy insulator activity. The insulator was inserted between defined enhancers and placed among divergently transcribed reporter genes (white and lacZ) containing distinct core promoter sequences. These assays indicate that mod(mdg4) is essential for the enhancer-blocking activity of the insulator DNA. Moreover, reductions in mod(mdg4)+ activity cause the insulator to function as a promoter-specific silencer that selectively represses white, but not lacZ. The repression of white does not affect the expression of the closely linked lacZ gene, suggesting that the insulator does not propagate changes in chromatin structure. These results provide an explanation for why mod(mdg4) exerts differential effects on different gypsy-induced mutations.
To determine the location of visual objects relative to the observer, the visual system must take account not only of the location of the stimulus on the retina, but also of the direction of gaze. In ...contrast, the perceived spatial relationship between visual stimuli is normally assumed to depend on retinal information alone, and not to require information about eye position. We now show, however, that the perceived alignment of three dots-tested by a vernier alignment task-is systematically altered in the period immediately preceding a saccade. Thus, information about eye position can modify not only the perceived relationship of the entire retinal image to the observer, but also the relations between elements within the image. The processing of relative position and of egocentric (observer-centred) position may therefore be less distinct than previously believed.
D-Glyceraldehyde-3-phosphate dehydrogenase (GAP-DH) is a protein containing no disulfide bonds; the guanidine HCl-denatured enzyme shows only a limited extent of refolding and reactivation upon ...dilution, and the enzyme is particularly prone to aggregation during the dilution process. With increasing GAPDH concentration, reactivation decreases and aggregation increases. The presence of protein disulfide isomerase in the dilution mixture markedly increases reactivation of GAPDH and at the same time prevents the aggregation of GAPDH as shown by light-scattering measurements. It is suggested that upon dilution, denatured GAPDH is faced with two competing processes of correct folding and assembly to yield the native enzyme and non-productive association of the partially refolded species to form aggregates. Independent of the isomerase activity as no disulfide bond is present in GAPDH, protein disulfide isomerase assists the refolding of GAPDH to its active state by suppressing aggregation in a way closely similar to the action of chaperones.
Summary
This study was designed to investigate the therapeutic efficacy of chitosan on Pneumocystis pneumonia (PCP) in immunosuppressed rats. The PCP rat model was established using intramuscular ...injections of dexamethasone sodium phosphate. To estimate treatment effects of chitosan on rat PCP, weight gain, lung weight, lung weight/body weight (LW/BW) ratio and per cent survival were measured and the HSP70 mRNA expression of Pneumocystis carinii was detected using real‐time PCR analysis. Rat lung tissues were stained with HE, and their pathological changes, inflammatory cells and alveolar macrophages were observed by light microscopy. Rat lymphocyte numbers and the concentrations of IL‐10, IFN‐γ and TNF‐α were measured by flow cytometry and ELISA analysis. Additionally, the ultrastructure of P. carinii was examined by electron microscopy to evaluate the effects of chitosan on the protist. Our results demonstrated that chitosan has some apparent treatment effects on rat PCP by reducing HSP70 mRNA expression and lung inflammation, increasing the concentrations of IL‐10 and IFN‐γ as well as CD4+ T‐lymphocyte numbers, reducing the CD8+ T‐lymphocyte numbers and the concentration of TNF‐α and inducing significant ultrastructural damage to P. carinii. Although its precise therapeutic mechanism has yet to be determined, these results lay a theoretical foundation for PCP chitosan therapy.
Recent studies indicate that nicastrin (NCT) and presenilins form functional components of a multimeric gamma-secretase complex required for the regulated intramembraneous proteolysis of Notch and ...beta-amyloid (Abeta) precursor protein (APP). To determine whether nicastrin is required for proteolytic processing of Notch and APP in mammals and the role of nicastrin in presenilin/gamma-secretase complex assembly, we generated nicastrin-deficient (NCT-/-) mice and derived fibroblasts from NCT-/- embryos. Nicastrin-null embryos died by embryonic day 10.5 and exhibited several patterning defects, including abnormal somite segmentation, phenotypes that are reminiscent of embryos lacking Notch1 or both presenilins. Importantly, secretion of Abeta peptides is abolished in NCT-/- fibroblasts, whereas it is reduced by approximately 50% in NCT+/- cells; the failure to generate Abeta peptides in NCT-/- cells is accompanied by destabilization of the presenilin/gamma-secretase complex and accumulation of APP-C-terminal fragments. Moreover, APP trafficking analysis in NCT-/- fibroblasts revealed a significant delay in the rate of APP reinternalization compared with that of control cells. Together, these results establish that nicastrin is an essential component of the multimeric gamma-secretase complex in mammals required for both gamma-secretase activity and APP trafficking and suggest that nicastrin may be a valuable therapeutic target for Alzheimer's disease.
Over-expressing GsGST14 from Glycine soja enhances alkaline tolerance of transgenic Medicago sativa Wang, Z.Y., Chinese Academy of Sciences, Changchun (China). Northeast Inst. of Geography and Agroecology; Song, F.B., Chinese Academy of Sciences, Changchun (China). Northeast Inst. of Geography and Agroecology; Cai, H., Northeast Agricultural Univ., Harbin (China). Plant Bioengineering Lab ...
Biologia plantarum,
09/2012, Letnik:
56, Številka:
3
Journal Article
Recenzirano
Odprti dostop
Glutathione-S-transferases (GSTs) are ubiquitous enzymes that play a key role in stress tolerance and cellular detoxification. The GST gene GsGST14 selected from the gene expression profiles of ...Glycine soja under alkaline stress was transformed into Medicago sativa. Transgenic alfalfa plants showed 1.73-1.99 times higher GST activity than wild-type plants. Transgenic alfalfa grew well in the presence of 100 mM NaHCO3, while wild-type plants exhibited chlorosis and stunted growth, even death. There were marked changes in malondialdehyde content and relative membrane permeability caused by alkaline stress in non-transgenic lines compared to transgenic lines. The results indicate that the gene GsGST14 could enhance alkaline resistance in transgenic alfalfa.
We present results of Very Long Baseline Array (VLBA) observations of PKS 0528+134 at five frequencies (2.3, 5.0, 8.4, 15.4, and 22.2 GHz). These quasi-simultaneous data enable us to study the ...spectral distribution of Very Long Baseline Interferometer (VLBI) components for the first time in this highly variable source, from which the central compact core is identified. Our observations indicate that there are two bendings for the jet motion at parsec scale. We provide an approximate spatial fit to the curved jet trajectory using the Steffen et al. (1995) helical model. We further investigate the proper motions of three jet components, which all show superluminal motion. At high frequencies (15.4 and 22.2 GHz) we detected a new component, which is estimated to be related to a radio burst peaking at about 2000.
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