Cosmic age, Statefinder and OmOm diagnostics in the decaying vacuum cosmology

As an extension of $\Lambda$CDM, the decaying vacuum model (DV) describes the dark energy as a varying vacuum whose energy density decays linearly with the Hubble parameter in the late-times, $\rho_\Lambda(t) \propto H(t)$, and produces the matter component. We examine the high-$z$ cosmic age problem in the DV model, and compare it with $\Lambda$CDM and the Yang-Mills condensate (YMC) dark energy model. Without employing a dynamical scalar field for dark energy, these three models share a similar behavior of late-time evolution. It is found that the DV model, like YMC, can accommodate the high-$z$ quasar APM 08279+5255, thus greatly alleviates the high-$z$ cosmic age problem. We also calculate the Statefinder $(r,s)$ and the {\it Om} diagnostics in the model. It is found that the evolutionary trajectories of $r(z)$ and $s(z)$ in the DV model are similar to those in the kinessence model, but are distinguished from those in $\Lambda$CDM and YMC. The ${\it Om}(z)$ in DV has a negative slope and its height depends on the matter fraction, while YMC has a rather flat ${\it Om}(z)$, whose magnitude depends sensitively on the coupling.Comment: 12 pages, 4 figures, with some correction

A thermal model for static current characteristics of AlGaN/GaN high electron mobility transistors including self-heating effect

2005-2006 > Academic research: refereed > Publication in refereed journalVersion of RecordPublishe

Augmenting bug localization with part-of-speech and invocation

Bug localization represents one of the most expensive, as well as time-consuming, activities during software maintenance and evolution. To alleviate the workload of developers, numerous methods have been proposed to automate this process and narrow down the scope of reviewing buggy files. In this paper, we present a novel buggy source-file localization approach, using the information from both the bug reports and the source files. We leverage the part-of-speech features of bug reports and the invocation relationship among source files. We also integrate an adaptive technique to further optimize the performance of the approach. The adaptive technique discriminates Top 1 and Top N recommendations for a given bug report and consists of two modules. One module is to maximize the accuracy of the first recommended file, and the other one aims at improving the accuracy of the fixed defect file list. We evaluate our approach on six large-scale open source projects, i.e. ASpectJ, Eclipse, SWT, Zxing, Birt and Tomcat. Compared to the previous work, empirical results show that our approach can improve the overall prediction performance in all of these cases. Particularly, in terms of the Top 1 recommendation accuracy, our approach achieves an enhancement from 22.73% to 39.86% for ASpectJ, from 24.36% to 30.76% for Eclipse, from 31.63% to 46.94% for SWT, from 40% to 55% for ZXing, from 7.97% to 21.99% for Birt, and from 33.37% to 38.90% for Tomcat

Virulence Genotype and Phylogenetic Groups in relation to Chinese Herb Resistance among Escherichia Coli from Patients with acute Pyelonephritis

Background: Clinical isolates of herb-resistant uropathogenic E. coli were isolated. It was possible that the virulence genotypes and phylogenetic background of E. coli differed between Chinese herb-resistant E. coli and -susceptible isolates. For this purpose, the prevalence of virulence factors (VFs) and phylogenetic background, with regard to Chinese herb resistance, among E. coli strains causing acute pyelonephritis from China were investigated.Materials and Methods: E. coli isolates from patients with acute pyelonephritis were used in this study. Standard disc diffusion methodology was used to test the susceptibility of Chinese herbal concoction against E. coli strains. Multiplex PCR amplifications employed three markers (chuA, yjaA, and TSPE4.C2) to classify E. coli isolates into one of four phylogenetic groups (group A, B1, B2, or D). The isolates were also tested for 14 virulence-associated traits (VFs) of uropathogenic E. coli.Results: A total of 115 E. coli strains were isolated. 79 (68.7%) were susceptible and 36 (31.3%) were resistant to the herbal concoction. 20.9% of the isolates encoded three or more of VFs for which they were screened, with 13.9% in susceptible isolates and 36.1% in resistant isolates. The key VFs (fyuA and/or iutA siderophores) present in >80% of isolates. The papA and papC adhesins were detected in the majority of resistant isolates (72.2% and 63.9% respectively). 78.5% of susceptible isolates belong to phylogenetic groups A, while 83.3% of resistant isolates belong to group B2.Conclusion: PapA and papC are significant VFs with an essential role in contributing to Chinese herb-resistance. Chinese herb-resistance is associated with a shift towards more virulent strains and B2 phylogenetic group.Key words: Escherichia coli; Virulence factors; Phylogenetic group; Chinese herb-resistance

Chinese Herbal Medicine: A Safe Alternative Therapy for Urinary Tract Infection in Patients with Renal Insufficiency

We have used reduced doses of Chinese herbs for estimation of urinary tract infections (UTIs) patients with stable impairment of renal function. A total of 33 adult female patients with moderately impaired renal function and symptomatic UTIs were included in this study. Urine cultures were carried out. Patients were monitored clinically and with various laboratory tests. Chinese herbal concoction divided by milligrams of creatinine per 100 ml were orally administrated for ten days. Three patients were excluded from final analysis. Most of the patients responded symptomatically to treatment. Chinese herbs eradicated the primary pathogen in 68.7% of the patients at the day 10 of treatment. Two patients relapsed (one had abbreviated courses of therapy) 6 to 8 days posttreatment. Organisms which recurred included Escherichia coli and Pseudomonas aeruginosa. Bacterial reinfections occurred 5 to 8 days posttreatment in four patients. Adverse reactions observed among the 30 patients were rare. Nausea (6.67%) and mild elevation of hepatic enzymes (3.33%) were probably drug related. Nausea disappeared when the therapy ended. Elevated hepatic enzymes resumed at the 2-week follow-up. Two patients demonstrated slight increases in serum creatinine on day 10 of treatment. One patient had a 12.5% elevation over baseline and the other had a 13.0% elevation. Serum creatinine values had improved in these two patients at 4-week follow-up. Chinese herbal medicine was effective and safe in the treatment of UTIs with renal insufficiency.Key words: Chinese herbs; Urinary tract infection; Renal insufficiency; Dose adjustment