592 research outputs found
Bayesian sequential experimental design for binary response data with application to electromyographic experiments
We develop a sequential Monte Carlo approach for Bayesian analysis of the experimental design for binary response data. Our work is motivated by surface electromyographic (SEMG) experiments, which can be used to provide information about the functionality of subjects' motor units. These experiments involve a series of stimuli being applied to a motor unit, with whether or not the motor unit res for each stimulus being recorded. The aim is to learn about how the probability of ring depends on the applied stimulus (the so-called stimulus response curve); One such excitability parameter is an estimate of the stimulus level for which the motor unit has a 50% chance of ring. Within such an experiment we are able to choose the next stimulus level based on the past observations. We show how sequential Monte Carlo can be used to analyse such data in an online manner. We then use the current estimate of the posterior distribution in order to choose the next stimulus level. The aim is to select a stimulus level that mimimises the expected loss. We will apply this loss function to the estimates of target quantiles from the stimulus-response curve. Through simulation we show that this approach is more ecient than existing sequential design methods for choosing the stimulus values. If applied in practice, it could more than halve the length of SEMG experiments
Agribusiness innovation: A pathway to sustainable economic growth in Africa
The paper considers the factors that drive a strong and competitive agri-business sector with particular attention to investment in research and development (R&D) for technological innovation as well as the broader drivers and risk factors of influence. It develops a case study and in particular contrasts the very successful value chain in Thailand with the weak one in Nigeria in order to highlight the implications for Nigerian government policy if it wishes to exploit the potential for a strong cassava agri-business sector
Land change detection and effective factors on forest land use changes: application of land change modeler and multiple linear regression
Reducing forest covered areas and changing it to pasture, agricultural, urban and rural areas is performed every year and this causes great damages in natural resources in a wide range. In order to identify the effective factors on reducing the forest cover area, multiple regression was used from 1995 to 2015 in Mazandaran forests. A Multiple regressions can link the decline in forest cover (dependent variable) and its effective factors (independent variable) are well explained. In this study, Landsat TM data of 1995 and Landsat ETM+ data of 2015 were analyzed and classified in order to investigate the changes in the forest area. The images were classified in two classes of forest and non-forest areas and also forest map with spatial variables of physiography and human were analyzed by regression equation. Detection satellite images showed that during the studied period there was found a reduction of forest areas up to approximately 257331 ha. The results of regression analysis indicated that the linear combination of income per capita, rain and temperature with determined coefficient 0.4 as independent variables were capable of estimating the reduction of forest area. The results of this study can be used as an efficient tool to manage and improve forests regarding physiographical and human characteristics.Keywords: Land change Modeler, Multiple linear regression, remote sensing, Mazandaran forest
Hyers-Ulam-Rassias stability of the additive-quadratic mappings in non-Archimedean Banach spaces
Aquaculture land-use policy: the case of clam farming in Thaibinh Province, Vietnam
Policy-making and enforcement remains centralized in Vietnam. Policies have been formulated with less scientific and public justification, thus being largely bureaucratic and infeasible, and in many cases, they have created plagues for people at the grass-roots levels. This article focuses on the implementation of policies related to intertidal land-use and supports for clam farming in the Thaibinh province as a case study to explore the impacts of policies on clam farming and farmers. During the period of 2011-2013, provincial policies on intertidal land allocation and technical and financial supports had boosted clam farming development in the province to a surprising extent. Rapid expansion of the clam farming area has created significant consequences for the farming sector, as well as farmer's lives. However, for the same provincial policies, but with different enforcement, different farming outcomes for clam farmers in the three study communes have resulted. Where farmers had more of a voice and choice in bidding for the intertidal areas they preferred, they faced fewer problems. It is, thus, suggested that a more decentralized policy-making and enforcement are needed, in which more scientific assessment and farmer participation are required to not only make government policy more successful in supporting farmers and achieving their expected outcomes, but also to provide farmers with more room to make their own farming decisions from which farming and marketing risks could be mitigated
Effect of pimecrolimus on postoperative peritoneal adhesions in rat: An experimental study
Introduction: Postoperative peritoneal adhesions (PPAs) is a common complication of abdominal surgeries causing significant morbidity and mortality. The inflammatory response to damaged peritoneal tissue is a speculated culprit. The aim of this study is to investigate the protective effect of pimecrolimus, an anti-inflammatory and immunomodulator agent, in formation of PPAs in rats. Methods: Complied with the Animal Research Reporting In Vivo Experiments (ARRIVE) Guidelines Checklist, 50 Albino rats underwent laparotomy and were allocated into 5 groups. In groups 1 to 3, topical pimecrolimus (25, 50 and 100 concentration, respectively) was applies on a scratched area of peritoneum. In group 4, only topical Eucerin was used and group 5, was the control group. On postoperative days 7 and 28, five rats from each group were randomly selected and the tensile strength and adhesiveness of intraabdominal fibrotic bundles were assessed. Results: There was no significant difference in tensile strength and adhesiveness, between the groups on postoperative day 7. On postoperative day 28, however, the tensile strength was significantly lower in pimecrolimus groups than in Eucerin (<0.001) and control (<0.001) groups. Groups with higher concentrations of pimecrolimus (group 2 and 3) developed significantly less adhesions than group 1, in which lower pimecrolimus concentration was used. Conclusion: Administration of topical pimecrolimus decrease adhesions and their tensile strength on postoperative day 28 in rats. © 2020 The Author
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