Towards a service-oriented e-infrastructure for multidisciplinary environmental research

Research e-infrastructures are considered to have generic and thematic parts. The generic part provids high-speed networks, grid (large-scale distributed computing) and database systems (digital repositories and data transfer systems) applicable to all research commnities irrespective of discipline. Thematic parts are specific deployments of e-infrastructures to support diverse virtual research communities. The needs of a virtual community of multidisciplinary envronmental researchers are yet to be investigated. We envisage and argue for an e-infrastructure that will enable environmental researchers to develop environmental models and software entirely out of existing components through loose coupling of diverse digital resources based on the service-oriented achitecture. We discuss four specific aspects for consideration for a future e-infrastructure: 1) provision of digital resources (data, models & tools) as web services, 2) dealing with stateless and non-transactional nature of web services using workflow management systems, 3) enabling web servce discovery, composition and orchestration through semantic registries, and 4) creating synergy with existing grid infrastructures

Credal Model Averaging: dealing robustly with model uncertainty on small data sets.

Datasets of population dynamics are typically characterized by a short temporal extension. In this condition, several alternative models typically achieve close accuracy, though returning quite different predictions (model uncertainty ). Bayesian model averaging (BMA) addresses this issue by averaging the prediction of the different models, using as weights the posterior probability of the models. However, an open problem of BMA is the choice of the prior probability of the models, which can largely impact on the inferences, especially when data are scarce. We present Credal Model Averaging (CMA), which addresses this problem by simultaneously considering a set of prior probability distributions over the models. This allows to represent very weak prior knowledge about the appropriateness of the different models and also to easily accommodate expert judgments, considering that in many cases the expert is not willing to commit himself to a single prior probability distribution. The predictions generated by CMA are intervals whose lengths shows the sensitivity of the predictions on the choice of the prior over the models

Prevalence of vertebral fracture in oldest old nursing home residents

Summary: We evaluated vertebral fracture prevalence using DXA-based vertebral fracture assessment and its influence on the Fracture Risk Assessment (FRAX) tool-determined 10-year fracture probability in a cohort of oldest old nursing home residents. More than one third of the subjects had prevalent vertebral fracture and 50% osteoporosis. Probably in relation with the prevailing influence of age and medical history of fracture, adding these information into FRAX did not markedly modify fracture probability. Introduction: Oldest old nursing home residents are at very high risk of fracture. The prevalence of vertebral fracture in this specific population and its influence on fracture probability using the FRAX tool are not known. Methods: Using a mobile DXA osteodensitometer, we studied the prevalence of vertebral fracture, as assessed by vertebral fracture assessment program, of osteoporosis and of sarcopenia in 151 nursing home residents. Ten-year fracture probability was calculated using appropriately calibrated FRAX tool. Results: Vertebral fractures were detected in 36% of oldest old nursing home residents (mean age, 85.9 ± 0.6years). The prevalence of osteoporosis and sarcopenia was 52% and 22%, respectively. Ten-year fracture probability as assessed by FRAX tool was 27% and 15% for major fracture and hip fracture, respectively. Adding BMD or VFA values did not significantly modify it. Conclusion: In oldest old nursing home residents, osteoporosis and vertebral fracture were frequently detected. Ten-year fracture probability appeared to be mainly determined by age and clinical risk factors obtained by medical history, rather than by BMD or vertebral fractur

Ant Colony System for a Dynamic Vehicle Routing Problem

An aboundant literature on vehicle routing problems is available. However, most of the work deals with static problems, where all data are known in advance, i.e. before the optimization has started. The technological advances of the last few years give rise to a new class of problems, namely the dynamic vehicle routing problems, where new orders are received as time progresses and must be dynamically incorporated into an evolving schedule. In this paper a dynamic vehicle routing problem is examined and a solving strategy, based on the Ant Colony System paradigm, is proposed. Some new public domain benchmark problems are defined, and the algorithm we propose is tested on them. Finally, the method we present is applied to a realistic case study, set up in the city of Lugano (Switzerland

Effect of deer density on tick infestation of rodents and the hazard of tick-borne encephalitis. II: Population and infection models

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Zinc increases the effects of essential amino acids-whey protein supplements in frail elderly

Abstract: Protein undernutrition is frequent in the elderly. It contributes to the development of osteoporosis, possibly via lower IGF-I. Dietary zinc can influence IGF-I production. Objectives: To determine the influence of dietary zinc addition on IGF-I and bone turnover responses to essential amino acids-whey (EAA-W) protein supplements in frail elderly. Design and setting: A daily oral protein supplement was given to hospitalized patients for 4 weeks. On a randomized, double-blind basis, patients received either an additional 30 mg/day of zinc or control. Participants: Sixty-one hospitalized elderly aged 66.7 to 105.8, with a mini-nutritional assessment score between 17 and 24 were enrolled. Measurements: Activities of daily living; dietary intakes; serum IGF-I, IGF-BP3, CrossLaps™, osteocalcin and zinc were measured before and after 1, 2 and 4 weeks of protein supplementation. Results: Serum IGF-I rapidly increased in both groups. Zinc accelerated this increase with changes of +48.2±14.3 and +22.4±4.7% (p<.05) by 1 week, in the zinc-supplemented and control groups, respectively. Zinc significantly decreased the serum bone resorption marker CrossLaps™ by already 1 week. Activities of daily living improved by +27.0±3.1 and +18.3±4.5% in zinc-supplemented and control groups, respectively. Conclusion: In the elderly, zinc supplementation accelerated the serum IGF-I response to EAA-W protein by 1 week and decreased a biochemical marker of bone resorptio