Winners and losers from Johne’s disease eradication from the Scottish dairy herd: a Markov-Chain simulation

In this paper, we evaluated the welfare effects of a hypothetical programme of Johne's disease eradication from the Scottish dairy herd on different stakeholders in the domestic milk market. We undertook the evaluation using a Markov-Chain simulation and applying an economic welfare analysis which takes into consideration the effects of an eradication programme on product price, on output quantity, on cost and on milk yield for given levels of supply and demand elasticities. We found that, following the eradication of the disease, milk yield per cow increased for all herd sizes in Scotland whereas price and unit cost of milk production fell. Consequently, milk consumers gained around £14.3 million in discounted economic surplus and producers with infected herds around £13.4 million whereas producers with uninfected herds lost around £10.7 million in discounted surplus. The gain in surplus made by consumers and owners of infected herds, however, more than made up for the loss in surplus made by owners of un-infected herds. Therefore, on balance, Scotland gained a net economic surplus of £17 million from the programme.Johne's, eradication programme, economic welfare effects, economic surplus, I180,

Managing animal health status information in the cattle market

The paper analyses the problem of information in the cattle market, particularly as it relates to the status of animal health, and discusses ways to limit it with the view to improving social surplus. Against this background, it aims to achieve three major objectives. Firstly, it describes the ways of improving the level of information through such schemes as Conventional Warranties and Third Party Certification and the different choices made by sellers and buyers in the presence of these schemes. Secondly, it studies the various ways by which these schemes make an impact on equilibria in different markets (i.e., the pooling market and the premium market), and, consequently, on the social surplus. Thirdly, it identifies the necessary conditions for a third party/public decision-maker to increase social surplus and reduce the negative externality caused by disease by managing and supporting Third Party Certification. The paper shows that product certification and product warranty cannot coexist because product warranty is suboptimal. It also shows that certification, and a possible supporting of certification or animal testing does not necessarily improve the safety of the trade.Asymmetric information, Third-Party certification, Disease Externalities, Livestock Production/Industries,

Use of high-dimensional spectral data to evaluate organic matter, reflectance relationships in soils

Recent breakthroughs in remote sensing technology have led to the development of a spaceborne high spectral resolution imaging sensor, HIRIS, to be launched in the mid-1990s for observation of earth surface features. The effects of organic carbon content on soil reflectance over the spectral range of HIRIS, and to examine the contributions of humic and fulvic acid fractions to soil reflectance was evaluated. Organic matter from four Indiana agricultural soils was extracted, fractionated, and purified, and six individual components of each soil were isolated and prepared for spectral analysis. The four soils, ranging in organic carbon content from 0.99 percent, represented various combinations of genetic parameters such as parent material, age, drainage, and native vegetation. An experimental procedure was developed to measure reflectance of very small soil and organic component samples in the laboratory, simulating the spectral coverage and resolution of the HIRIS sensor. Reflectance in 210 narrow (10 nm) bands was measured using the CARY 17D spectrophotometer over the 400 to 2500 nm wavelength range. Reflectance data were analyzed statistically to determine the regions of the reflective spectrum which provided useful information about soil organic matter content and composition. Wavebands providing significant information about soil organic carbon content were located in all three major regions of the reflective spectrum: visible, near infrared, and middle infrared. The purified humic acid fractions of the four soils were separable in six bands in the 1600 to 2400 nm range, suggesting that longwave middle infrared reflectance may be useful as a non-destructive laboratory technique for humic acid characterization

JPL preferred parts list: Reliable electronic components

The JPL Preferred Parts List was prepared to provide a basis for selection of electronic parts for JPL spacecraft programs. Supporting tests for the listed parts were designed to comply with specific spacecraft environmental requirements. The list tabulates the electronic, magnetic, and electromechanical parts applicable to all JPL electronic equipment wherein reliability is a major concern. The parts listed are revelant to equipment supplied by subcontractors as well as fabricated at the laboratory

Simulation, modelling and development of the metris RCA

In partnership with Metris UK we discuss the utilisation of modelling and simulation methods in the development of a revolutionary 7-axis Robot CMM Arm (RCA). An offline virtual model is described, facilitating pre-emptive collision avoidance and assessment of optimal placement of the RCA relative to scan specimens. Workspace accessibility of the RCA is examined under a range of geometrical assumptions and we discuss the effects of arbitrary offsets resulting from manufacturing tolerances. Degeneracy is identified in the number of ways a given pose may be attained and it is demonstrated how a simplified model may be exploited to solve the inverse kinematics problem of finding the “correct” set of joint angles. We demonstrate how the seventh axis may be utilised to avoid obstacles or otherwise awkward poses, giving the unit greater dexterity than traditional CMMs. The results of finite element analysis and static force modelling on the RCA are presented which provide an estimate of the forces exerted on the internal measurement arm in a range of poses

Widowhood and cognitive decline in adults aged 50 and over: A systematic review and meta-analysis

While widowhood is known to be associated with poorer physical and mental health outcomes, studies examining the association of widowhood with cognition have yielded mixed results. This review aimed to elucidate the link between widowhood and cognitive decline. A systematic search of Medline, Embase, PsycInfo, CINAHL and Scopus (until December 2020) was conducted to identify studies on the association between widowhood (vs. being married) and cognition in cognitively healthy adults aged 50 +. A cross-sectional meta-analysis (of 10 studies; n = 24,668) found a significant association of widowhood with cognition (g = − 0.36, 95% CI [− 0.47, − 0.25], p = < 0.001). Meta-regressions suggested that study design, cognitive domain measured, sample age, difference in mean age between widowed and married groups, and study continent did not account for observed heterogeneity. A longitudinal meta-analysis (of 3 studies; n = 10,378) found that the “continually widowed” group (from baseline to follow-up) showed significantly steeper declines in cognition compared to the “continually married” group (g = − 0.15, 95%CI [− 0.19, − 0.10], p = < 0.001). Findings indicate that widowhood may be a risk factor for cognitive decline. As there are no effective treatments for cognitive impairment, studying mechanisms by which widowhood might be associated with poorer cognition could inform prevention programs for those who have experienced spousal bereavement

Incremental Grid-like Layout Using Soft and Hard Constraints

We explore various techniques to incorporate grid-like layout conventions into a force-directed, constraint-based graph layout framework. In doing so we are able to provide high-quality layout---with predominantly axis-aligned edges---that is more flexible than previous grid-like layout methods and which can capture layout conventions in notations such as SBGN (Systems Biology Graphical Notation). Furthermore, the layout is easily able to respect user-defined constraints and adapt to interaction in online systems and diagram editors such as Dunnart.Comment: Accepted to Graph Drawing 201

Evaluation of the Potential of Triethanolamine to Alter Hepatic Choline Levels in Female B6C3F1 Mice

Triethanolamine (TEA), a widely used nongenotoxic alcoholamine, has recently been reported to cause an increased incidence of liver tumors in female B6C3F1 mice, but not in males nor in Fischer 344 rats. Choline deficiency induces liver cancer in rodents, and TEA could compete with choline uptake into tissues. The potential of TEA to cause choline deficiency in the liver of these mice as a mode of tumorigenesis was investigated. Groups of female B6C3F1 mice were administered 0 (vehicle) or a maximum tolerated dosage (MTD) of 1000 mg/kg/day TEA (Trial I) and 0, 10, 100, 300, or 1000 mg/kg/day TEA (Trial II) in acetone vehicle via skin painting 5 days/week for 3 weeks. Female CDF® rats were also administered 0 or an MTD dosage of 250 mg/kg/day TEA (Trial II) in a similar manner. No clinical signs of toxicity were noted, and upon sacrifice, levels of hepatic choline, its primary storage form, phosphocholine (PCho), and its primary oxidation product, betaine, were determined. A statistically significant decrease in PCho and betaine, was observed at the high dosage (26–42%) relative to controls and a dose-related, albeit variable, decrease was noted in PCho levels. Choline levels were also decreased 13–35% at the high dose level in mice. No changes in levels of choline or metabolites were noted in treated rats. A subsequent evaluation of the potential of TEA to inhibit the uptake of 3H-choline by cultured Chinese Hamster Ovary Cells revealed a dose-related effect upon uptake. It was concluded that TEA may cause liver tumors in mice via a choline-depletion mode of action and that this effect is likely caused by the inhibition of choline uptake by cells

Microbial carbon mineralization in tropical lowland and montane forest soils of Peru

Climate change is affecting the amount and complexity of plant inputs to tropical forest soils. This is likely to influence the carbon (C) balance of these ecosystems by altering decomposition processes e.g., "positive priming effects" that accelerate soil organic matter mineralization. However, the mechanisms determining the magnitude of priming effects are poorly understood. We investigated potential mechanisms by adding (13)C labeled substrates, as surrogates of plant inputs, to soils from an elevation gradient of tropical lowland and montane forests. We hypothesized that priming effects would increase with elevation due to increasing microbial nitrogen limitation, and that microbial community composition would strongly influence the magnitude of priming effects. Quantifying the sources of respired C (substrate or soil organic matter) in response to substrate addition revealed no consistent patterns in priming effects with elevation. Instead we found that substrate quality (complexity and nitrogen content) was the dominant factor controlling priming effects. For example a nitrogenous substrate induced a large increase in soil organic matter mineralization whilst a complex C substrate caused negligible change. Differences in the functional capacity of specific microbial groups, rather than microbial community composition per se, were responsible for these substrate-driven differences in priming effects. Our findings suggest that the microbial pathways by which plant inputs and soil organic matter are mineralized are determined primarily by the quality of plant inputs and the functional capacity of microbial taxa, rather than the abiotic properties of the soil. Changes in the complexity and stoichiometry of plant inputs to soil in response to climate change may therefore be important in regulating soil C dynamics in tropical forest soils.This study was financed by the UK Natural Environment Research Council (NERC) grant NE/G018278/1 and is a product of the Andes Biodiversity and Ecosystem Research Group consortium (www.andesconservation.org); Patrick Meir was also supported by ARC FT110100457