Inclusive semileptonic B decays from QCD with NLO accuracy for power suppressed terms

We present the results of a calculation of the perturbative QCD corrections for the semileptonic inclusive width of a heavy flavored meson. Within the Heavy Quark Expansion we analytically compute the QCD correction to the coefficient of power suppressed contribution of the chromo-magnetic operator in the limit of vanishing mass of the final state quark. The important phenomenological applications are decays of bottom mesons, and to the less extend, charmed mesons.Comment: 4 pages, 2 figure

Accuracy of hyaluronic acid level for predicting liver fibrosis stages in patients with hepatitis C virus

BACKGROUND: In patients with chronic hepatitis C virus, liver biopsy is the gold standard for assessing liver disease stage; nevertheless, it is prone to complications, some of them serious. Non-invasive methods have been proposed as surrogate markers for liver fibrosis. It was shown that serum hyaluronic acid (HA) level increases with the development for liver fibrosis. The aim of this study was to evaluate the diagnostic value of HA as well as to determine the HA level cut-off for predicting the presence or absence of fibrosis, severe fibrosis, and cirrhosis. RESULTS: 405 patients with chronic hepatitis C were prospectively included with biomarker measurement and liver biopsy done the same day: 151 in the training set (only biopsy lengths of 25 mm or more) and 254 in the validation set. For the discrimination of significant fibrosis, severe fibrosis, and cirrhosis in the training set, the areas under curve (AUCs) were 0.75 ± 0.03, 0.82 ± 0.02, and 0.89 ± 0.03, respectively. Absence of significant fibrosis, severe fibrosis, and cirrhosis can be predicted by HA levels of 16, 25, and 50 μg/l, respectively (with negative predictive values of 82%, 89%, and 100%, in the same order). Presence of significant fibrosis, severe fibrosis, and cirrhosis can be predicted by HA levels of 121, 160, and 237 μg/l, respectively (with positive predictive values of 94%, 100%, and 57%, in the same order). CONCLUSION: In the validation set, HA was accurate in predicting significant fibrosis, severe fibrosis, and cirrhosis with AUCs of 0.73, 0.77, and 0.97, respectively. Moreover, accurate HA level cut-offs were defined for predicting significant fibrosis, severe fibrosis, and cirrhosis. Thus, the study supports that HA level may be clinically useful as a non-invasive marker for liver fibrosis and/or cirrhosis

The vulnerability of public spaces: challenges for UK hospitals under the 'new' terrorist threat

This article considers the challenges for hospitals in the United Kingdom that arise from the threats of mass-casualty terrorism. Whilst much has been written about the role of health care as a rescuer in terrorist attacks and other mass-casualty crises, little has been written about health care as a victim within a mass-emergency setting. Yet, health care is a key component of any nation's contingency planning and an erosion of its capabilities would have a significant impact on the generation of a wider crisis following a mass-casualty event. This article seeks to highlight the nature of the challenges facing elements of UK health care, with a focus on hospitals both as essential contingency responders under the United Kingdom's civil contingencies legislation and as potential victims of terrorism. It seeks to explore the potential gaps that exist between the task demands facing hospitals and the vulnerabilities that exist within them

Quantification and parametric imaging of renal cortical blood flow in vivo based on Patlak graphical analysis

Quantification and parametric imaging of renal cortical blood flow in vivo based on Patlak graphical analysis. Patlak graphical analysis was applied to quantify renal cortical blood flow with N-13 ammonia and dynamic positron emission tomography. Measurements were made in a swine model of kidney transplantation with a wide range of normal and abnormal renal blood flows (N = 57 studies) and in 20 healthy human volunteers (N = 45 studies). Estimates of renal cortical blood flow by the Patlak method were compared to those from a two-compartment model for N-13 ammonia. In addition, estimates of renal cortical blood flow by the N-13 ammonia PET approach were compared in 10 normal human volunteers to estimates by the metabolically inert, freely diffusible O-15 water and a one-compartment model. Patlak graphical analysis estimates of renal cortical blood flow correlated linearly with the standard two-compartment model in pigs (y = -0.05 + 1.01x, r = 0.99) and in humans (y = 0.57 + 0.88x, r = 0.93). Estimates of renal cortical blood flow by O-15 water in human volunteers were also linearly correlated with those by N-13 ammonia and the Patlak graphical analysis (y = 0.71 + 0.84x, r = 0.86). Renal cortical blood flow estimates were highly reproducible both with N-13 ammonia and O-15 water measurements in humans. It is concluded that the Patlak graphical analysis with N-13 ammonia dynamic positron emission tomographic imaging renders accurate and reproducible estimates of renal cortical blood flow. Moreover, the graphical analysis approach is 1,000 times faster than the standard model fitting approach and suitable for generating parametric images of renal blood flow in the clinical setting

Antiviral Activities and Putative Identification of Compounds in Microbial Extracts from the Hawaiian Coastal Waters

Marine environments are a rich source of significant bioactive compounds. The Hawaiian archipelago, located in the middle of the Pacific Ocean, hosts diverse microorganisms, including many endemic species. Thirty-eight microbial extracts from Hawaiian coastal waters were evaluated for their antiviral activity against four mammalian viruses including herpes simplex virus type one (HSV-1), vesicular stomatitis virus (VSV), vaccinia virus and poliovirus type one (poliovirus-1) using in vitro cell culture assay. Nine of the 38 microbial crude extracts showed antiviral potencies and three of these nine microbial extracts exhibited significant activity against the enveloped viruses. A secosteroid, 5α(H),17α(H),(20R)-beta-acetoxyergost-8(14)-ene was putatively identified and confirmed to be the active compound in these marine microbial extracts. These results warrant future in-depth tests on the isolation of these active elements in order to explore and validate their antiviral potential as important therapeutic remedies

Sea ice diatom contributions to Holocene nutrient utilization in East Antarctica

Combined high-resolution Holocene δ30Sidiat and δ13Cdiat paleorecords are presented from theSeasonal Ice Zone, East Antarctica. Both data sets reflect periods of increased nutrient utilization by diatomsduring the Hypsithermal period (circa 7800 to 3500 calendar years (cal years) B.P.), coincident with a higherabundance of open water diatom species (Fragilariopsis kerguelensis), increased biogenic silica productivity(%BSi), and higher regional summer temperatures. The Neoglacial period (after circa 3500 cal years B.P.) isreflected by an increase in sea ice indicative species (Fragilariopsis curta and Fragilariopsis cylindrus,upto50%) along with a decrease in %BSi and δ13Cdiat(< 18‰ to 23‰). However, over this period, δ30Sidiatdata show an increasing trend, to some of the highest values in the Holocene record (average of +0.43‰).Competing hypotheses are discussed to account for the decoupling trend in utilization proxies including ironfertilization, species-dependent fractionation effects, and diatom habitats. Based on mass balance calculations,we highlight that diatom species derived from the semi-enclosed sea ice environment may have a confoundingeffect upon δ30Sidowncorecompositions of the seasonal sea ice zone. A diatom composition, with approximately28% of biogenic silica derived from the sea ice environment (diat-SI) can account for the increased averagecompo sition of δ30Sidiatduring the Neoglacial. These data highlight the significant role sea ice diatoms can playwith relation to their export in sediment records, which has implications on productivity reconstructions fromthe seasonal ice zone