303 research outputs found

    Randomized GCUR decompositions

    Full text link
    By exploiting the random sampling techniques, this paper derives an efficient randomized algorithm for computing a generalized CUR decomposition, which provides low-rank approximations of both matrices simultaneously in terms of some of their rows and columns. For large-scale data sets that are expensive to store and manipulate, a new variant of the discrete empirical interpolation method known as L-DEIM, which needs much lower cost and provides a significant acceleration in practice, is also combined with the random sampling approach to further improve the efficiency of our algorithm. Moreover, adopting the randomized algorithm to implement the truncation process of restricted singular value decomposition (RSVD), combined with the L-DEIM procedure, we propose a fast algorithm for computing an RSVD based CUR decomposition, which provides a coordinated low-rank approximation of the three matrices in a CUR-type format simultaneously and provides advantages over the standard CUR approximation for some applications. We establish detailed probabilistic error analysis for the algorithms and provide numerical results that show the promise of our approaches

    BASIC STUDY FOR COAL MOISTURE CONTROL INTEGRATING PNEUMATIC CLASSIFICATION TECHNIQUE

    Get PDF
    A technique of coal moisture control integrating pneumatic classification with flue gas as heating medium was put forward. With this technique, refined coal moisture control can be realized accompanying classification in one process, and considerable high-quality energy can be saved in coking and milling procedure. In this paper, coal classification and moisture control behaviors was investigated at different conditions. Based on experimental results, the basic parameters for the technique were worked out accordingly

    Placebo devices as effective control methods in acupuncture clinical trials : a systematic review

    Get PDF
    While the use of acupuncture has been recognised by the World Health Organisation, its efficacy for many of the common clinical conditions is still undergoing validation through randomised controlled trials (RCTs). A credible placebo control for such RCTs to enable meaningful evaluation of its efficacy is to be established. While several non-penetrating acupuncture placebo devices, namely the Streitberger, the Park and the Takakura Devices, have been developed and used in RCTs, their suitability as inert placebo controls needs to be rigorously determined. This article systematically reviews these devices as placebo interventions. Electronic searches were conducted on four English and two Chinese databases from their inceptions to July 2014; hand searches of relevant references were also conducted. RCTs, in English or Chinese language, comparing acupuncture with one of the aforementioned devices as the control intervention on human participants with any clinical condition and evaluating clinically related outcomes were included. Thirty-six studies were included for qualitative analysis while 14 were in the meta-analysis. The meta-analysis does not support the notion of either the Streitberger or the Park Device being inert control interventions while none of the studies involving the Takakura Device was included in the meta-analysis. Sixteen studies reported the occurrence of adverse events, with no significant difference between verum and placebo acupuncture. Author-reported blinding credibility showed that participant blinding was successful in most cases; however, when blinding index was calculated, only one study, which utilised the Park Device, seemed to have an ideal blinding scenario. Although the blinding index could not be calculated for the Takakura Device, it was the only device reported to enable practitioner blinding. There are limitations with each of the placebo devices and more rigorous studies are needed to further evaluate their effects and blinding credibility

    β-Arrestin 2 Promotes Hepatocyte Apoptosis by Inhibiting AKT Protein

    Get PDF
    Recent studies reveal that multifunctional protein β-arrestin 2 (Arrb2) modulates cell apoptosis. Survival and various aspects of liver injury were investigated in WT and Arrb2KO mice after bile duct ligation (BDL). We found that deficiency of Arrb2 enhances survival and attenuates hepatic injury and fibrosis. Following BDL, Arrb2-deficient mice as compared with WT controls displayed a significant reduction of hepatocyte apoptosis as demonstrated by the TUNEL assay. Following BDL, the levels of phospho-Akt and phospho-glycogen synthase kinase 3β (GSK3β) in the livers were significantly increased in Arrb2 KO compared with WT mice, although p-p38 increased in WT but not in Arrb2-deficient mice. Inhibition of GSK3β following BDL decreases hepatic apoptosis and decreased p-p38 in WT mice but not in Arrb2 KO mice. Activation of Fas receptor with Jo2 reduces phospho-Akt and increases apoptosis in WT cells and WT mice but not in Arrb2-deficient cells and Arrb2-deficient mice. Consistent with direct interaction of Arrb2 with and regulating Akt phosphorylation, the expression of a full-length or N terminus but not the C terminus of Arrb2 reduces Akt phosphorylation and coimmunoprecipates with Akt. These results reveal that the protective effect of deficiency of Arrb2 is due to loss of negative regulation of Akt due to BDL and decreased downstream GSK3β and p38 MAPK signaling pathways

    U-Shaped Relationship Between Functional Outcome and Serum Uric Acid in Ischemic Stroke

    No full text
    Background/Aims: We sought to assess a consecutive number of patients with first-ever acute ischemic stroke (AIS), the clinical relevance in regard to functional outcome of the serum uric acid (SUA) measured at admission. Methods: In 2 prospective centers for observational study, serum concentrations of SUA were measured on admission in the serum of 710 consecutive patients with AIS. SUA concentrations were determined by high-performance liquid chromatography. SUA, NIH stroke scale (NIHSS), and conventional risk factors were evaluated to determine their value to predict functional outcome within 3 months. Results: During the follow-up, an unfavorable functional outcome (defined as a mRS score > 2) was found in 219 (30.8%) patients. The unfavorable functional outcome distribution across the SUA quartiles ranged between 12.4% (third quartile) and 50.6% (first quartile). After adjusting for all other significant outcome predictors, SUA concentration remained an independent unfavorable outcome predictor with an adjusted OR of 0.996 (95% CI, 0.993-0.998; P< 0.001). Conclusions: The data show that the U-shaped nature of the exposure-risk relationship was more prominent when the data were assessed in deciles (based on the SUA values). This model predicted the lowest relative risk of unfavorable outcome in the 67th percentile (corresponding to 309 µmol/L). SUA was significantly associated with the risk of poor functional outcomes in Chinese patients with stroke

    Effects of captivity and artificial breeding on microbiota in feces of the red-crowned crane (Grus japonensis)

    Get PDF
    Reintroduction of the threatened red-crowned crane has been unsuccessful. Although gut microbiota correlates with host health, there is little information on gut microbiota of cranes under different conservation strategies. The study examined effects of captivity, artificial breeding and life stage on gut microbiota of red-crown cranes. The gut microbiotas of wild, captive adolescent, captive adult, artificially bred adolescent and artificially bred adult cranes were characterized by next-generation sequencing of 16S rRNA gene amplicons. The gut microbiotas were dominated by three phyla: Firmicutes (62.9%), Proteobacteria (29.9%) and Fusobacteria (9.6%). Bacilli dominated the ‘core’ community consisting of 198 operational taxonomic units (OTUs). Both captivity and artificial breeding influenced the structures and diversities microbiota of the gut. Especially, wild cranes had distinct compositions of gut microbiota from captive and artificially bred cranes. The greatest alpha diversity was found in captive cranes, while wild cranes had the least. According to the results of ordination analysis, influences of captivity and artificial breeding were greater than that of life stage. Overall, captivity and artificial breeding influenced the gut microbiota, potentially due to changes in diet, vaccination, antibiotics and living conditions. Metagenomics can serve as a supplementary non-invasive screening tool for disease control
    • …
    corecore