Transport Phenomena and Structuring in Shear Flow of Suspensions near Solid Walls

In this paper we apply the lattice-Boltzmann method and an extension to particle suspensions as introduced by Ladd et al. to study transport phenomena and structuring effects of particles suspended in a fluid near sheared solid walls. We find that a particle free region arises near walls, which has a width depending on the shear rate and the particle concentration. The wall causes the formation of parallel particle layers at low concentrations, where the number of particles per layer decreases with increasing distance to the wall.Comment: 14 pages, 14 figure

Telaprevir-based triple-therapy in patients with chronic hepatitis C in Germany: a 12-week interim analysis of real-life data

Telaprevir (TVR)-based triple therapy in patients (pts) with chronic hepatitis C (HCV) in daily practice in Germany is investigated in this non-interventional study. Aims are the evaluation of the implementation of futility rules, as well as safety and efficacy of TVR-based therapy. This prospective, multi-center study investigates TVR-based therapy in therapy-naïve and pretreated pts with genotype 1 chronic HCV in Germany, including pts with HIV co-infection. Patients are treated with a combination of TVR, ribavirin and peg-interferon. This interim analysis includes data from the first 100 pts (12.5% of the planned total) at 32 sites completing 12 weeks (W) of treatment. 66% of pts were pretreated for HCV. 36.4% of pts with pre-treatment were prior relapsers and 30.3% null or partial responders. Cirrhosis was present in 11% of all pts at baseline. HCV RNA levels below 800.000 IU/ml at baseline were present in 50% of pts. 67% of pts showed rapid virological response (RVR, undetectable HCV RNA at W4). Adherence to the futility rule (treatment stop if HCV-RNA>1000 IU/ml at W4) was 100% (N=9). At W12, 91.4% of pts had undetectable HCV RNA. 57.7% of therapy-naïve pts and 86.4% of previous relapsers were HCV-RNA negative at both W4 and 12 (70.8% in total). Only one patient achieving RVR at W4 suffered a virologic breakthrough. Nearly all pts (99%) had adverse events (AE) during the first 12W, 6% reported serious adverse events (SAE). AEs were mostly mild (63.9%) or moderate (34.6%) and frequently mentioned dry skin/pruritus (54%), gastrointestinal disorders (48%), anorectal discomfort (30%), rash (29%) and anemia (23%). Rash was mostly rated as mild or moderate (97.1%). An Hb decrease<12 g/dl (female) or<13 g/dl (male) was reported in 87% of pts. Mean Hb levels decreased from 14.8 g/dl at baseline to 10.6 g/dl at W12; Hb levels<8.5 g/dl at any time within the first 12W of treatment were present in 11% of anemia cases and 6.6% required transfusion. Only one patient received erythropoietin treatment. 2 cases each of anemia and rash were considered as SAE. These interim results suggest that TVR-based triple-therapy is efficient against GT1 chronic hepatitis C in a real life setting. Adherence to futility rules was confirmed in all patients. As observed in clinical trials, adverse events were reported frequently, including anemia and rash. As more data become available, results will be updated

The fate of the homoctenids (Tentaculitoidea) during the Frasnian-Famennian mass extinction (Late Devonian)

The homoctenids (Tentaculitoidea) are small, conical-shelled marine animals which are amongst the most abundant and widespread of all Late Devonian fossils. They were a principal casualty of the Frasnian-Famennian (F-F, Late Devonian) mass extinction, and thus provide an insight into the extinction dynamics. Despite their abundance during the Late Devonian, they have been largely neglected by extinction studies. A number of Frasnian-Famennian boundary sections have been studied, in Poland, Germany, France, and the United States. These sections have yielded homoctenids, which allow precise recognition of the timing of the mass extinction. It is clear that the homoctenids almost disappear from the fossil record during the latest Frasnian “Upper Kellwasser Event”. The coincident extinction of this pelagic group, and the widespread development of intense marine anoxia within the water column, provides a causal link between anoxia and the F-F extinction. Most notable is the sudden demise of a group, which had been present in rock-forming densities, during this anoxic event. One new species, belonging to Homoctenus is described, but is not formally named here

Organic carbon content and carbon isotope variations across the Permo-Triassic boundary in the Gartnerkofel-1 borehole, Carnic Alps, Austria

The Gartnerkofel borehole is one of the most thoroughly studied and described Permo-Triassic sections in the world. Detailed bulk organic carbon isotope studies show a negative base shift from − 24‰ to − 28‰ in the Latest Permian which latter value persists into the Earliest Triassic after which it decreases slightly to − 26‰. Two strongly negative peaks of > − 38‰ in the Latest Permian and a lesser peak of − 31‰ in the Early Triassic are too negative to be due to a greater proportion of more negative organic matter and must be due to very negative methane effects. The overall change to more negative values across the Bulla/Tesero boundary fits the relative rise in sea level for this transition based on the facies changes. A positive shift in organic carbon isotope values at the Late Permian Event Horizon may be due to an increase in land-derived organic detritus at this level—a feature shown by all Tethyan Permo-Triassic boundary sections though these other sections do not have the same values. Carbonate carbon isotope trends are similar in all sections dropping by 2–3 units across the Permo-Triassic boundary. Gartnerkofel carbonate oxygen values are surprisingly, considering the ubiquitous dolomitization, compatible with values elsewhere and indicate reasonable tropical temperatures of 60 °C in the Latest Permian sabkhas to 20–40 °C in the overlying marine transition beds. Increased land-derived input at the Late Permian Event Horizon may be due to offshore transport by tsunamis whose deposits have been recognized in India at this level

Characteristics of hepatitis C virus resistance in an international cohort after a decade of direct-acting antivirals

Background & Aims: Direct-acting antiviral (DAA) regimens provide a cure in >95% of patients with chronic HCV infection. However, in some patients in whom therapy fails, resistance-associated substitutions (RASs) can develop, limiting retreatment options and risking onward resistant virus transmission. In this study, we evaluated RAS prevalence and distribution, including novel NS5A RASs and clinical factors associated with RAS selection, among patients who experienced DAA treatment failure. Methods: SHARED is an international consortium of clinicians and scientists studying HCV drug resistance. HCV sequence linked metadata from 3,355 patients were collected from 22 countries. NS3, NS5A, and NS5B RASs in virologic failures, including novel NS5A substitutions, were examined. Associations of clinical and demographic characteristics with RAS selection were investigated. Results: The frequency of RASs increased from its natural prevalence following DAA exposure: 37% to 60% in NS3, 29% to 80% in NS5A, 15% to 22% in NS5B for sofosbuvir, and 24% to 37% in NS5B for dasabuvir. Among 730 virologic failures, most were treated with first-generation DAAs, 94% had drug resistance in ≥1 DAA class: 31% single-class resistance, 42% dual-class resistance (predominantly against protease and NS5A inhibitors), and 21% triple-class resistance. Distinct patterns containing ≥2 highly resistant RASs were common. New potential NS5A RASs and adaptive changes were identified in genotypes 1a, 3, and 4. Following DAA failure, RAS selection was more frequent in older people with cirrhosis and those infected with genotypes 1b and 4. Conclusions: Drug resistance in HCV is frequent after DAA treatment failure. Previously unrecognized substitutions continue to emerge and remain uncharacterized. Lay summary: Although direct-acting antiviral medications effectively cure hepatitis C in most patients, sometimes treatment selects for resistant viruses, causing antiviral drugs to be either ineffective or only partially effective. Multidrug resistance is common in patients for whom DAA treatment fails. Older patients and patients with advanced liver diseases are more likely to select drug-resistant viruses. Collective efforts from international communities and governments are needed to develop an optimal approach to managing drug resistance and preventing the transmission of resistant viruses