Rare events in networks with internal and external noise

We study rare events in networks with both internal and external noise, and develop a general formalism for analyzing rare events that combines pair-quenched techniques and large-deviation theory. The probability distribution, shape, and time scale of rare events are considered in detail for extinction in the Susceptible-Infected-Susceptible model as an illustration. We find that when both types of noise are present, there is a crossover region as the network size is increased, where the probability exponent for large deviations no longer increases linearly with the network size. We demonstrate that the form of the crossover depends on whether the endemic state is localized near the epidemic threshold or not

Sofosbuvir and Daclatasvir Combination Therapy in a Liver Transplant Recipient With Severe Recurrent Cholestatic Hepatitis C

Recurrent HCV infection following liver transplantation can lead to accelerated allograft injury that is difficult to treat with interferon. The aim of this study is to describe the first ever use of an interferon‐free, all oral regimen in a liver transplant recipient with severe recurrent HCV. A 54‐year‐old male with HCV genotype 1b developed severe cholestatic HCV at 6 months posttransplant with ascites, AST 503 IU/mL, alkaline phosphatase of 298 IU/mL, HCV RNA of 12 000 000 IU/mL, and histological cholestasis with pericellular fibrosis. Sofosbuvir, an HCV polymerase inhibitor (400 mg/day), and daclatasvir, an HCV NS5A replication complex inhibitor (60 mg/day), were co‐administered for 24 weeks. Within 4 weeks of initiating treatment, serum HCV RNA levels became undetectable and liver biochemistries normalized with concomitant resolution of ascites. The patient achieved a sustained virological response with undetectable HCV RNA at 9 months posttreatment. During and following treatment, the daily dose and blood level of tacrolimus remained stable and unchanged. The rapid and sustained suppression of HCV replication in this liver transplant recipient provides great promise for the use of combination oral antiviral regimens in other immunosuppressed and interferon refractory HCV patients. A patient with severe cholestatic hepatitis C virus genotype 1b infection at nine months after liver transplantation was successfully treated with a six‐month course of oral sofosbuvir in combination with daclatasvir and remains HCV RNA negative during posttreatment follow‐up with improved liver biochemistries and health.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/98302/1/ajt12209.pd

Movements and habitat use of native and invasive piscivorous fishes in a temperate and channelized lowland river

Lowland temperate rivers provide important habitats for piscivorous fishes, but with their year-round spatial and temporal habitat use is often poorly understood, including their use of off-channel habitats. Here, the movements and habitat use of the piscivorous native Northern pike Esox lucius and invasive pikeperch Sander lucioperca were investigated using acoustic telemetry in the highly regulated (through impoundment) lower River Severn, Western England over a 12-month period, where off-channel habitat availability was limited to a single boat marina. The movements of both species varied with season and temperature, with both species moving greater distances in spring. Increasing water temperatures up to 15 °C resulted in a higher frequency of movements of both species, but movements then decreased at temperatures higher than this. Northern pike detections in the river increased in periods of lower river discharge and warmer temperatures, with the off-channel refuge providing an important habitat all year round (78% of detections occurred there). While 63% of pikeperch detections also occurred in the marina, 89% of these detections occurred between December and April. These results thus emphasise the importance of this limited off-channel habitat as potential spawning locations for invasive pikeperch and foraging areas for native Northern pike

Insights into toxic prymnesium parvum blooms:The role of sugars and algal viruses

Prymnesium parvum is a toxin-producing microalga that causes harmful algal blooms globally, which often result in large-scale fish kills that have severe ecological and economic implications. Although many toxins have previously been isolated from P. parvum, ambiguity still surrounds the responsible ichthyotoxins in P. parvum blooms and the biotic and abiotic factors that promote bloom toxicity. A major fish kill attributed to P. parvum occurred in Spring 2015 on the Norfolk Broads, a low-lying set of channels and lakes (Broads) found on the East of England. Here, we discuss how water samples taken during this bloom have led to diverse scientific advances ranging from toxin analysis to discovery of a new lytic virus of P. parvum, P. parvum DNA virus (PpDNAV-BW1). Taking recent literature into account, we propose key roles for sialic acids in this type of viral infection. Finally, we discuss recent practical detection and management strategies for controlling these devastating blooms

Streamlined Calibrations of the ATLAS Precision Muon Chambers for Initial LHC Running

The ATLAS Muon Spectrometer is designed to measure the momentum of muons with a resolution of dp/p = 3% and 10% at 100 GeV and 1 TeV momentum respectively. For this task, the spectrometer employs 355,000 Monitored Drift Tubes (MDTs) arrayed in 1200 Chambers. Calibration (RT) functions convert drift time measurements into tube-centered impact parameters for track segment reconstruction. RT functions depend on MDT environmental parameters and so must be appropriately calibrated for local chamber conditions. We report on the creation and application of a gas monitor system based calibration program for muon track reconstruction in the LHC startup phase.Comment: 25 pages, 21 figure

Individual variability in the movement ecology of Northern pike Esox lucius in a highly connected wetland system

Maintaining hydrological connectivity is important for sustaining freshwater fish populations as the high habitat connectivity supports large-scale fish movements, enabling individuals to express their natural behaviours and spatial ecology. Northern pike Esox lucius is a freshwater apex predator that requires access to a wide range of functional habitats across its lifecycle, including spatially discrete foraging and spawning areas. Here, pike movement ecology was assessed using acoustic telemetry and stable isotope analysis in the River Bure wetland system, eastern England, comprising of the Bure mainstem, the River Ant and Thurne tributaries, plus laterally connected lentic habitats, and a system of dykes and ditches. Of 44 tagged pike, 30 were tracked for over 100 days, with the majority of detections being in the laterally connected lentic habitats and dykes and ditches, but with similar numbers of pike detected across all macrohabitats. The movement metrics of these pike indicated high individual variability, with total ranges to over 26 km, total movements to over 1182 km and mean daily movements to over 2.9 km. Pike in the Thurne tributary were more vagile than those in the Ant and Bure, and with larger Thurne pike also having relatively high proportions of large-bodied and highly vagile common bream Abramis brama in their diet, suggesting the pike movements were potentially related to bream movements. These results indicate the high individual variability in pike movements, which was facilitated here by their access to a wide range of connected macrohabitats due to high hydrological connectivity

Movements and habitat use of native and invasive piscivorous fishes in a temperate and channelized lowland river

Lowland temperate rivers provide important habitats for piscivorous fishes, but with their year-round spatial and temporal habitat use is often poorly understood, including their use of off-channel habitats. Here, the movements and habitat use of the piscivorous native Northern pike Esox lucius and invasive pikeperch Sander lucioperca were investigated using acoustic telemetry in the highly regulated (through impoundment) lower River Severn, Western England over a 12-month period, where off-channel habitat availability was limited to a single boat marina. The movements of both species varied with season and temperature, with both species moving greater distances in spring. Increasing water temperatures up to 15 °C resulted in a higher frequency of movements of both species, but movements then decreased at temperatures higher than this. Northern pike detections in the river increased in periods of lower river discharge and warmer temperatures, with the off-channel refuge providing an important habitat all year round (78% of detections occurred there). While 63% of pikeperch detections also occurred in the marina, 89% of these detections occurred between December and April. These results thus emphasise the importance of this limited off-channel habitat as potential spawning locations for invasive pikeperch and foraging areas for native Northern pike

Process evaluation results from the HEALTHY physical education intervention

Process evaluation is an assessment of the implementation of an intervention. A process evaluation component was embedded in the HEALTHY study, a primary prevention trial for Type 2 diabetes implemented over 3 years in 21 middle schools across the United States. The HEALTHY physical education (PE) intervention aimed at maximizing student engagement in moderate-to-vigorous physical activity through delivery of structured lesson plans by PE teachers. Process evaluation data collected via class observations and interventionist interviews assessed fidelity, dose delivered, implementor participation, dose received and barriers. Process evaluation results indicate a high level of fidelity in implementing HEALTHY PE activities and offering 225 min of PE every 10 school days. Concerning dose delivered, students were active for approximately 33 min of class, representing an average of 61% of the class time. Results also indicate that PE teachers were generally engaged in implementing the HEALTHY PE curriculum. Data on dose received showed that students were highly engaged with the PE intervention; however, student misbehavior was the most common barrier observed during classes. Other barriers included teacher disengagement, large classes, limited gym space and poor classroom management. Findings suggest that the PE intervention was generally implemented and received as intended despite several barriers