8,705 research outputs found

    Micro-electroforming metallic bipolar electrodes for mini-DMFC stacks

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    This paper describes the development of metallic bipolar plate fabrication using micro-electroforming process for mini-DMFC (direct methanol fuel cell) stacks. Ultraviolet (UV) lithography was used to define micro-fluidic channels using a photomask and exposure process. Micro-fluidic channels mold with 300 micrometers thick and 500 micrometers wide were firstly fabricated in a negative photoresist onto a stainless steel plate. Copper micro-electroforming was used to replicate the micro-fluidic channels mold. Following by sputtering silver (Ag) with 1.2 micrometers thick, the metallic bipolar plates were completed. The silver layer is used for corrosive resistance. The completed mini-DMFC stack is a 2x2 cm2 fuel cell stack including a 1.5x1.5 cm2 MEA (membrane electrode assembly). Several MEAs were assembly into mini-DMFC stacks using the completed metallic bipolar plates. All test results showed the metallic bipolar plates suitable for mini-DMFC stacks. The maximum output power density is 9.3mW/cm2 and current density is 100 mA/cm2 when using 8 vol. % methanol as fuel and operated at temperature 30 degrees C. The output power result is similar to other reports by using conventional graphite bipolar plates. However, conventional graphite bipolar plates have certain difficulty to be machined to such micro-fluidic channels. The proposed micro-electroforming metallic bipolar plates are feasible to miniaturize DMFC stacks for further portable 3C applications.Comment: Submitted on behalf of EDA Publishing Association (http://irevues.inist.fr/handle/2042/16838

    Informatics expertise to support life and health sciences research and industry

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    Computing Infrastructure and Informatics to Support Life Sciences R&D, Therapeutics, Diagnostics and Economic Development PanelInterdisciplinary collaboration between computational sciences and life/health sciences is a hallmark of the MU Informatics Institute (MUII) and its new Informatics Ph.D. program. The Institute was established to foster synergy and interdisciplinary research applications in animal, plant, human health, geospatial and microbial sciences. Creative faculty and modern computation-based research facilities combine to enable groundbreaking collaborative research that relies heavily on informatics tools and expertise. In this talk, I will briefly introduce the informatics expertise of MUII core faculty in supporting experimental scientist's R&D activities with commercialization potentials by using an example scenario in personalized medicine. There are six signature research areas that are underpinning components: (1) high-throughput sequence assembly and analysis, (2) structural bioinformatics - prediction, retrievals, and interactions, (3) large-scale and high-throughput phenotype analysis, (4) data mining and knowledge discovery from large-scale omics databases and electronic health records (5) visualization and parallelism of informatics data, and (6) geospatial informatics

    Caregiver Integration During Discharge Planning for Older Adults to Reduce Resource Use: A Metaanalysis

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    Objectives To determine the effect of integrating informal caregivers into discharge planning on postdischarge cost and resource use in older adults. Design A systematic review and metaanalysis of randomized controlled trials that examine the effect of discharge planning with caregiver integration begun before discharge on healthcare cost and resource use outcomes. MEDLINE, EMBASE, and the Cochrane Library databases were searched for all English‐language articles published between 1990 and April 2016. Setting Hospital or skilled nursing facility. Participants Older adults with informal caregivers discharged to a community setting. Measurements Readmission rates, length of and time to post‐discharge rehospitalizations, costs of postdischarge care. Results Of 10,715 abstracts identified, 15 studies met the inclusion criteria. Eleven studies provided sufficient detail to calculate readmission rates for treatment and control participants. Discharge planning interventions with caregiver integration were associated with a 25% fewer readmissions at 90 days (relative risk (RR) = 0.75, 95% confidence interval (CI) = 0.62–0.91) and 24% fewer readmissions at 180 days (RR = 0.76, 95% CI = 0.64–0.90). The majority of studies reported statistically significant shorter time to readmission, shorter rehospitalization, and lower costs of postdischarge care among discharge planning interventions with caregiver integration. Conclusion For older adults discharged to a community setting, the integration of caregivers into the discharge planning process reduces the risk of hospital readmission

    Calculating second derivatives of population growth rates for ecology and evolution

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    © The Author(s), 2014. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Methods in Ecology and Evolution 5 (2014): 473–482, doi:10.1111/2041-210X.12179.Second derivatives of the population growth rate measure the curvature of its response to demographic, physiological or environmental parameters. The second derivatives quantify the response of sensitivity results to perturbations, provide a classification of types of selection and provide one way to calculate sensitivities of the stochastic growth rate. Using matrix calculus, we derive the second derivatives of three population growth rate measures: the discrete-time growth rate λ, the continuous-time growth rate r = log λ and the net reproductive rate R0, which measures per-generation growth. We present a suite of formulae for the second derivatives of each growth rate and show how to compute these derivatives with respect to projection matrix entries and to lower-level parameters affecting those matrix entries. We also illustrate several ecological and evolutionary applications for these second derivative calculations with a case study for the tropical herb Calathea ovandensis.This work was supported by a National Science Foundation Graduate Research Fellowship under Grant 1122374, by NSF Grants DEB-1145017 and DEB1257545, and by Advanced Grant 322989 from the European Research Council

    Frequency-dependent two-sex models : a new approach to sex ratio evolution with multiple maternal conditions

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    © The Author(s), 2016. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Ecology and Evolution 6 (2016): 6855–6879, doi:10.1002/ece3.2202.Mothers that experience different individual or environmental conditions may produce different proportions of male to female offspring. The Trivers-Willard hypothesis, for instance, suggests that mothers with different qualities (size, health, etc.) will use different sex ratios if maternal quality differentially affects sex-specific reproductive success. Condition-dependent, or facultative, sex ratio strategies like these allow multiple sex ratios to coexist within a population. They also create complex population structure due to the presence of multiple maternal conditions. As a result, modeling facultative sex ratio evolution requires not only sex ratio strategies with multiple components, but also two-sex population models with explicit stage structure. To this end, we combine nonlinear, frequency-dependent matrix models and multidimensional adaptive dynamics to create a new framework for studying sex ratio evolution. We illustrate the applications of this framework with two case studies where the sex ratios depend one of two possible maternal conditions (age or quality). In these cases, we identify evolutionarily singular sex ratio strategies, find instances where one maternal condition produces exclusively male or female offspring, and show that sex ratio biases depend on the relative reproductive value ratios for each sex.National Science Foundation Graduate Research Fellowship Grant Number: 1122374; National Science Foundation Grant Numbers: DEB1145017, DEB1257545; European Research Council Grant Number: 322989; Woods Hole Oceanographic Institution Academic Programs Offic
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