Experimental pig-to-pig transmission dynamics for African swine fever virus, Georgia 2007/1 strain

African swine fever virus (ASFV) continues to cause outbreaks in domestic pigs and wild boar in Eastern European countries. To gain insights into its transmission dynamics, we estimated the pig-to-pig basic reproduction number (R 0) for the Georgia 2007/1 ASFV strain using a stochastic susceptible-exposed-infectious-recovered (SEIR) model with parameters estimated from transmission experiments. Models showed that R 0 is 2·8 [95% confidence interval (CI) 1·3–4·8] within a pen and 1·4 (95% CI 0·6–2·4) between pens. The results furthermore suggest that ASFV genome detection in oronasal samples is an effective diagnostic tool for early detection of infection. This study provides quantitative information on transmission parameters for ASFV in domestic pigs, which are required to more effectively assess the potential impact of strategies for the control of between-farm epidemic spread in European countries.ISSN:0950-2688ISSN:1469-440

Intermediate reading exercises for use with the Durrell Analysis of Reading Difficulty.

Thesis (Ed.M.)--Boston Universit

Non-invasive evaluation of pulmonary glutathione in the exhaled breath condensate of otherwise healthy alcoholics

SummaryBackgroundChronic alcoholism is associated with an elevated risk for pulmonary infection and a 3-fold chance for incidence and mortality of acute respiratory distress syndrome with critical injury. Limited sampling of the alveolar lining fluid has restricted clinical studies of the role of glutathione (GSH) redox balance in pulmonary function and diseased states. Non-invasive sampling in the exhaled breath condensate (EBC) to monitor alveolar GSH would facilitate research in pulmonary oxidative stress.MethodsEBC was collected from otherwise healthy subjects with and without a history of alcohol abuse. Reduced and oxidized EBC glutathione (GSH and GSSG, respectively), pH, and hydrogen peroxide were measured.ResultsGSH was statistically decreased in alcohol abusers only when normalized to protein (4.7nmol/mg protein [0.75, 11.4] vs. 13.4 [7.8, 26.4], p=0.03). In contrast, GSSG was significantly elevated in the EBC from alcohol abusers when compared to controls, 5.62 [0.45, 8.94] vs. 0.50nM [0.38, 0.80], p=0.03. Thus, a greater percentage was in the oxidized GSSG form when subjects abused alcohol (35.3% [11.8, 58.1] vs. 5.2 [3.6, 6.1], p<0.001). These concentrations represented a 40mV shift in GSH redox state towards a more oxidized state.ConclusionsProper sample preparation was essential to prevent GSH loss and artificial oxidation. The shift in redox potential or %GSSG, which were not affected by dilution, may serve as better markers of pulmonary oxidative stress. Furthermore, these data suggested that the oxidant stress observed in the lavage fluid of otherwise healthy alcoholics could be measured non-invasively in the EBC

Ecological Effects of Fear: How Spatiotemporal Heterogeneity in Predation Risk Influences Mule Deer Access to Forage in a Sky‐Island System

Forage availability and predation risk interact to affect habitat use of ungulates across many biomes. Within sky‐island habitats of the Mojave Desert, increased availability of diverse forage and cover may provide ungulates with unique opportunities to extend nutrient uptake and/or to mitigate predation risk. We addressed whether habitat use and foraging patterns of female mule deer (Odocoileus hemionus) responded to normalized difference vegetation index (NDVI), NDVI rate of change (green‐up), or the occurrence of cougars (Puma concolor). Female mule deer used available green‐up primarily in spring, although growing vegetation was available during other seasons. Mule deer and cougar shared similar habitat all year, and our models indicated cougars had a consistent, negative effect on mule deer access to growing vegetation, particularly in summer when cougar occurrence became concentrated at higher elevations. A seemingly late parturition date coincided with diminishing NDVI during the lactation period. Sky‐island populations, rarely studied, provide the opportunity to determine how mule deer respond to growing foliage along steep elevation and vegetation gradients when trapped with their predators and seasonally limited by aridity. Our findings indicate that fear of predation may restrict access to the forage resources found in sky islands

Anatomic Femoral and Tibial Tunnel Placement During Anterior Cruciate Ligament Reconstruction: Anteromedial Portal All-Inside and Outside-In Techniques

Tunnel malposition is one of the most common technical reasons for anterior cruciate ligament reconstruction failure. Small changes in tunnel placement can result in significant differences in outcome. More anatomic placement of the tunnels can lead to greater knee stability and a more accurate reproduction of native knee kinematics. This Technical Note describes 2 tibial tunnel–independent methods to obtain anatomic femoral tunnel placement. The all-inside anteromedial portal technique requires only minimal surgical incisions but allows precise femoral tunnel placement. However, hyperflexion of the knee is required, adequate surgical assistance is necessary, and this technique may be susceptible to graft-tunnel mismatch. The outside-in technique may be more beneficial in obese patients, skeletally immature patients, or revision cases. On the downside, it does require an additional 2-cm surgical incision. This article also provides surgical pearls to fine-tune tibial tunnel placement

Dynamic Behavior in Piezoresponse Force Microscopy

Frequency dependent dynamic behavior in Piezoresponse Force Microscopy (PFM) implemented on a beam-deflection atomic force microscope (AFM) is analyzed using a combination of modeling and experimental measurements. The PFM signal comprises contributions from local electrostatic forces acting on the tip, distributed forces acting on the cantilever, and three components of the electromechanical response vector. These interactions result in the bending and torsion of the cantilever, detected as vertical and lateral PFM signals. The relative magnitudes of these contributions depend on geometric parameters of the system, the stiffness and frictional forces of tip-surface junction, and operation frequencies. The dynamic signal formation mechanism in PFM is analyzed and conditions for optimal PFM imaging are formulated. The experimental approach for probing cantilever dynamics using frequency-bias spectroscopy and deconvolution of electromechanical and electrostatic contrast is implemented.Comment: 65 pages, 15 figures, high quality version available upon reques

Reduced avian body condition due to global warming has little reproductive or population consequences

Climate change has strong effects on traits such as phenology and physiology. Studies typically assume that climate-induced trait changes will have consequences for population dynamics, but explicit tests are rare. Body condition reflects energy storage and may directly affect how much can be invested in reproduction and survival. However, the causal pathway by which decreased body condition impacts population dynamics has never been quantified across multiple populations and species. Therefore, we lack a general understanding of the consequences of changes in condition for variables more relevant for conservation, such as population size. Using structural equation modeling, we investigate how temperature-induced changes in body condition affect reproduction, and the subsequent impact on population growth rates of 19 bird species across 80 Dutch sites over a 21-year period. Warmer temperatures were associated with decreased body condition, which led to both decreased and increased reproduction at different sites, cancelling out any overall effect. The indirect effect of temperature on population growth (via body condition and reproduction) only explained within-species variation in the total effects of temperature on population growth. Instead, the direct effect of temperature on population growth (unrelated to condition and reproduction) was the most important pathway underlying the total effects of temperature on population growth, suggesting that unknown variables are mediating this effect. About half of the species are expected to increase under global warming, but this variation was not associated with any species characteristic. Overall, body condition responses to global warming are common, but their consequences on reproduction and subsequently population growth contribute relatively little to the total temperature impacts on population dynamics. Given that warming temperatures have strong effects on population dynamics, understanding the pathways via which temperature impacts population dynamics will be crucial for our ability to predict climate change effects in the future and improve conservation efforts

Intense physical activity is associated with cognitive performance in the elderly

Numerous studies have reported positive impacts of physical activity on cognitive function. However, the majority of these studies have utilised physical activity questionnaires or surveys, thus results may have been influenced by reporting biases. Through the objective measurement of routine levels of physical activity via actigraphy, we report a significant association between intensity, but not volume, of physical activity and cognitive functioning. A cohort of 217 participants (aged 60–89 years) wore an actigraphy unit for 7 consecutive days and underwent comprehensive neuropsychological assessment. The cohort was stratified into tertiles based on physical activity intensity. Compared with individuals in the lowest tertile of physical activity intensity, those in the highest tertile scored 9%, 9%, 6% and 21% higher on the digit span, digit symbol, Rey Complex Figure Test (RCFT) copy and Rey Figure Test 30-min recall test, respectively. Statistically, participants in the highest tertile of physical activity intensity performed significantly better on the following cognitive tasks: digit symbol, RCFT copy and verbal fluency test (all P<0.05). The results indicate that intensity rather than quantity of physical activity may be more important in the association between physical activity and cognitive function

Quantum and Classical Noise in Practical Quantum Cryptography Systems based on polarization-entangled photons

Quantum-cryptography key distribution (QCKD) experiments have been recently reported using polarization-entangled photons. However, in any practical realization, quantum systems suffer from either unwanted or induced interactions with the environment and the quantum measurement system, showing up as quantum and, ultimately, statistical noise. In this paper, we investigate how ideal polarization entanglement in spontaneous parametric downconversion (SPDC) suffers quantum noise in its practical implementation as a secure quantum system, yielding errors in the transmitted bit sequence. Because all SPDC-based QCKD schemes rely on the measurement of coincidence to assert the bit transmission between the two parties, we bundle up the overall quantum and statistical noise in an exhaustive model to calculate the accidental coincidences. This model predicts the quantum-bit error rate and the sifted key and allows comparisons between different security criteria of the hitherto proposed QCKD protocols, resulting in an objective assessment of performances and advantages of different systems.Comment: Rev Tex Style, 2 columns, 7 figures, (a modified version will appear on PRA