351 research outputs found
Incentive Systems under ex post Moral Hazard to Control Outbreaks of Classical Swine Fever in the Netherlands
Livestock Production/Industries,
An Incentive System for Salmonella Control in the Pork Supply Chain
This paper presents a dynamic principal-agent analysis of an incentive system for Salmonella control in the pork supply chain. The incentive system determines quality premiums to the producer, testing frequencies for hogs delivered, as well as charges to the producer for testing and penalties. Using cost estimates and technical parameters, we evaluate the cost effectiveness of plant and farm control measures and trade-offs between prevalence reduction and related costs and gains. We also assess the impact of ownership structure on incentive system parameters and performance for a wide range of prevalence threshold levels. Differences in control actions, bacteriological prevalence and the overall welfare gain for the chain are very small across ownership structures. Changes in the prevalence threshold level lead to substantial changes in the use of farm and plant control packages and performance measures.dynamic programming, food quality, principal-agent, Food Consumption/Nutrition/Food Safety, Livestock Production/Industries,
A framework for the design and analysis of incentive systems for food safety control in supply chains
Since 2005 the EU food industry has primary legal responsibility for food safety control. This requires new responsibilities and relationships between government and industry, and between companies. This research presents a framework for incentive systems for food safety control in supply chains. It emphasizes key elements of food safety control from multiple perspectives and provides insights for the design and analysis of incentive systems for food safety control. An incentive system combines inter-company incentive mechanisms with intra-company decision making processes to control a hazard within the legal environment. Incentive mechanisms, which consist of a performance measure and a performance reward, induce companies to use control measures. The framework can be used to analyze the effectiveness and efficiency of alternative incentive systems in which companies have to cooperate with partners from other stages of the supply chain.Incentive mechanism, food safety, supply chain control., Agricultural and Food Policy,
Effectiveness of All-Oral Antiviral Regimens in 996 Human Immunodeficiency Virus/Hepatitis C Virus Genotype 1âCoinfected Patients Treated in Routine Practice
Background.Large cohorts are needed to assess human immunodeficiency virus (HIV)/hepatitis C virus (HCV) real-world treatment outcomes. We examined the effectiveness of ledipasvir/sofosbuvir with or without ribavirin (LDV/SOF ± RBV) and ombitasvir/ paritaprevir/ritonavir plus dasabuvir (OPrD) ± RBV in HIV/HCV genotype 1 (GT1)-coinfected patients initiating HCV therapy in clinical practice.Methods.Observational intent-to-treat cohort analysis using the Veterans Affairs Clinical Case Registry to identify HIV/HCV GT1-coinfected veterans initiating 12 weeks of LDV/SOF ± RBV or OPrD ± RBV. Multivariate models of sustained virologic response (SVR) included age, race, cirrhosis, proton pump inhibitor (PPI) prescription, prior HCV treatment, body mass index, genotype subtype, and HCV treatment regimen.Results.Nine hundred ninety-six HIV/HCV GT1-coinfected veterans initiated therapy: 757 LDV/SOF, 138 LDV/SOF + RBV, 28 OPrD, and 73 OPrD + RBV. Overall SVR was 90.9% (823/905); LDV/SOF 92.1% (631/685), LDV/SOF + RBV 86.3% (113/131), OPrD 88.9% (24/27), and OPrD + RBV 88.7% (55/62). SVR was 85.9% (176/205) and 92.4% (647/700) in those with and without cirrhosis (P = .006). SVR was similar between African Americans (90.5% [546/603]) and all others (91.7% [277/302]). PPI use with LDV/SOF ± RBV did not affect SVR (89.7% [131/146] with PPI and 91.5% [613/670] without PPI). Cirrhosis was predictive of reduced SVR (0.51 [95% confidence interval {CI}, .31-.87]; P = .01). Median creatinine change did not differ among patients receiving LDV/SOF and tenofovir disoproxil fumarate (TDF) without a protease inhibitor (PI) (0.18 [interquartile range {IQR}, 0.08-0.30]; n = 372), LDV/SOF and TDF/PI (0.17 [IQR, 0.04-0.30]; n = 100), and LDV/SOF without TDF (0.15 [IQR, 0.00-0.30]; n = 423).Conclusions.SVR rates in HIV/HCV GT1-coinfected patients were high. African American race or PPI use with LDV/SOF ± RBV was not associated with lower SVR rates, but cirrhosis was. Renal function did not worsen on LDV/SOF regimens with TDF
Exploiting solar visible-range observations by inversion techniques: from flows in the solar subsurface to a flaring atmosphere
Observations of the Sun in the visible spectral range belong to standard
measurements obtained by instruments both on the ground and in the space.
Nowadays, both nearly continuous full-disc observations with medium resolution
and dedicated campaigns of high spatial, spectral and/or temporal resolution
constitute a holy grail for studies that can capture (both) the long- and
short-term changes in the dynamics and energetics of the solar atmosphere.
Observations of photospheric spectral lines allow us to estimate not only the
intensity at small regions, but also various derived data products, such as the
Doppler velocity and/or the components of the magnetic field vector. We show
that these measurements contain not only direct information about the dynamics
of solar plasmas at the surface of the Sun but also imprints of regions below
and above it. Here, we discuss two examples: First, the local time-distance
helioseismology as a tool for plasma dynamic diagnostics in the near subsurface
and second, the determination of the solar atmosphere structure during flares.
The methodology in both cases involves the technique of inverse modelling.Comment: 29 pages, 15 figures. Accepted for publication in the book "Reviews
in Frontiers of Modern Astrophysics: From Space Debris to Cosmology" (eds
Kabath, Jones and Skarka; publisher Springer Nature) funded by the European
Union Erasmus+ Strategic Partnership grant "Per Aspera Ad Astra Simul"
2017-1-CZ01-KA203-03556
Effectiveness of treatment with pegylated interferon and ribavirin in an unselected population of patients with chronic hepatitis C: A Danish nationwide cohort study
<p>Abstract</p> <p>Background</p> <p>The effect of peginterferon and ribavirin treatment on chronic hepatitis C virus (HCV) infection has been established in several controlled clinical studies. However, the effectiveness of treatment and predictors of treatment success in routine clinical practice remains to be established. Our aim was to estimate the effectiveness of peginterferon and ribavirin treatment in unselected HCV patients handled in routine clinical practice. The endpoint was sustained virological response (SVR), determined by the absence of HCV RNA 24 weeks after the end of treatment.</p> <p>Methods</p> <p>We determined the proportion of SVR in a nationwide, population-based cohort of 432 patients with chronic HCV infection who were starting treatment, and analyzed the impact of known covariates on SVR by using a logistic regression analysis.</p> <p>Results</p> <p>The majority of treated patients had genotype 1 (133 patients) and genotype 2/3 (285 patients) infections, with 44% and 72%, respectively, obtaining SVR. Other than genotype, the predictors of SVR were age †45 years at the start of treatment, completion of unmodified treatment, the absence of cirrhosis and non-European origin.</p> <p>Conclusions</p> <p>The effectiveness of peginterferon and ribavirin treatment for chronic hepatitis C in a routine clinical practice is comparable to that observed in controlled clinical trials, with a higher SVR rate in genotype 2 and 3 patients compared to genotype 1 patients. Our data further indicate that age at start of treatment is a strong predictor of SVR irrespective of HCV genotype, with patients 45 years or younger having a higher SVR rate.</p
Moving magnetoencephalography towards real-world applications with a wearable system
Imaging human brain function with techniques such as magnetoencephalography1 (MEG) typically requires a subject to perform tasks whilst their head remains still within a restrictive scanner. This artificial environment makes the technique inaccessible to many people, and limits the experimental questions that can be addressed. For example, it has been difficult to apply neuroimaging to investigation of the neural substrates of cognitive development in babies and children, or in adult studies that require unconstrained head movement (e.g. spatial navigation). Here, we develop a new type of MEG system that can be worn like a helmet, allowing free and natural movement during scanning. This is possible due to the integration of new quantum sensors2,3 that do not rely on superconducting technology, with a novel system for nulling background magnetic fields. We demonstrate human electrophysiological measurement at millisecond resolution whilst subjects make natural movements, including head nodding, stretching, drinking and playing a ball game. Results compare well to the current state-of-the-art, even when subjects make large head movements. The system opens up new possibilities for scanning any subject or patient group, with myriad applications such as characterisation of the neurodevelopmental connectome, imaging subjects moving naturally in a virtual environment, and understanding the pathophysiology of movement disorders
Observation of associated near-side and away-side long-range correlations in âsNN=5.02ââTeV proton-lead collisions with the ATLAS detector
Two-particle correlations in relative azimuthal angle (ÎÏ) and pseudorapidity (Îη) are measured in âsNN=5.02ââTeV p+Pb collisions using the ATLAS detector at the LHC. The measurements are performed using approximately 1ââÎŒb-1 of data as a function of transverse momentum (pT) and the transverse energy (ÎŁETPb) summed over 3.1<η<4.9 in the direction of the Pb beam. The correlation function, constructed from charged particles, exhibits a long-range (2<|Îη|<5) ânear-sideâ (ÎÏâŒ0) correlation that grows rapidly with increasing ÎŁETPb. A long-range âaway-sideâ (ÎÏâŒÏ) correlation, obtained by subtracting the expected contributions from recoiling dijets and other sources estimated using events with small ÎŁETPb, is found to match the near-side correlation in magnitude, shape (in Îη and ÎÏ) and ÎŁETPb dependence. The resultant ÎÏ correlation is approximately symmetric about Ï/2, and is consistent with a dominant cosâĄ2ÎÏ modulation for all ÎŁETPb ranges and particle pT
A model of Earthâs magnetic field derived from 2Â years of Swarm satellite constellation data
Efficacy and Tolerability of Peginterferon Alpha Plus Ribavirin in the Routine Daily Treatment of Chronic Hepatitis C Patients in Korea: A Multi-Center, Retrospective Observational Study
Background/Aims: We aimed to evaluate the efficacy and safety of peginterferon plus ribavirin for chronic hepatitis C (CHC) patients under real life setting in Korea. Methods: We retrospectively analyzed the medical records of 758 CHC patients treated with peginterferon plus ribavirin between 2000 and 2008 from 14 university hospitals in the Gyeonggi-Incheon area in Korea. Results: Hepatitis C virus (HCV) genotype 1 was detected in 61.2% of patients, while genotype 2 was detected in 35.5%. Baseline HCV RNA level was >= 6x10(5) IU/mL in 51.6% of patients. The sustained virological response (SVR) rate was 59.6% regardless of genotype; 53.6% in genotype 1 and 71.4% in genotype 2/3. On multivariate analysis, male gender (p=0.011), early virological response (p<0.001), genotype 2/3 (p<0.001), HCV RNA <6x10(5) IU/mL (p=0.005) and adherence to the drug >80% of the planned dose (p<0.001) were associated with SVR. The rate of premature discontinuation was 35.7%. The main reason for withdrawal was intolerance to the drug due to common adverse events or cytopenia (48.2%). Conclusions: Our data suggest that the efficacy of peginterferon and ribavirin therapy in Koreans is better in Koreans than in Caucasians for the treatment of CHC, corroborating previous studies that have shown the superior therapeutic efficacy of this regimen in Asians.This study was supported by the Korean Association for the Study of the Liver in 2009
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