1,858 research outputs found

    Kinky Brane Worlds

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    We present a toy model for five-dimensional heterotic M-theory where bulk three-branes, originating in 11 dimensions from M five-branes, are modelled as kink solutions of a bulk scalar field theory. It is shown that the vacua of this defect model correspond to a class of topologically distinct M-theory compactifications. Topology change can then be analysed by studying the time evolution of the defect model. In the context of a four-dimensional effective theory, we study in detail the simplest such process, that is the time evolution of a kink and its collision with a boundary. We find that the kink is generically absorbed by the boundary thereby changing the boundary charge. This opens up the possibility of exploring the relation between more complicated defect configurations and the topology of brane-world models.Comment: 31 pages, Latex, 6 eps-figure

    Participatory systems mapping for sustainable consumption: Discussion of a method promoting systemic insights

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    The paper describes our usage of and experience with the method of participatory systems mapping. The method, developed for the purpose of facilitating knowledge brokerage, builds on participatory modelling approaches and applications and was used in several events involving both researchers and policy makers. The paper presents and discusses examples of how different types of participatory interaction with causal loop diagrams ("system maps") produced different insights on issues related to sustainable consumption and enabled participatory reflection and sharing of knowledge. Together, these insights support a systemic understanding of the issues and thus the method provides instruments for coping with complexity when formulating policies for sustainable consumption. Furthermore the paper discusses the ability of the method - and its limits - to connect mental models of participants through structured discussion and thus bridge boundaries between different communities

    Patient's reactions to digital rectal examination of the prostate

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    OBJECTIVE: In recent years, there has been a rise in the incidence of prostate cancer (PCa), and routine screening for the disease has become a well accepted clinical practice. Even with the recognized benefit of this approach, some men are still reluctant to undergo digital rectal examination (DRE). For this reason, we designed the present study in order to better understand men's reactions about this method of screening. The aim was to identify possible drawbacks that could be overcome to increase DRE. MATERIALS AND METHODS: We randomly selected 269 patients that were enrolled in an institutional PCa screening program. They were first asked to answer a question regarding their preferred position to undergo the examination. Following this step, they answered a questionnaire in which physical and psychological reactions regarding the DRE were presented. Finally, we used a visual analogical scale (VAS) to analyze the perception of pain during DRE. RESULTS: The supine position was preferred for most patients (53.9%). Before DRE, about 59.4% of patients felt that the exam would be acceptable. After DRE, this figure increased to 91.5% (p < 0.001). Mean VAS score during DRE was 1.69 on a scale with a range between 0 and 10 (0 = no pain; 10 = extreme pain). CONCLUSION: Patient expectations about DRE were negative before examination and changed significantly following the exam. Pain during examination was negligible, contrary to the prevalent belief. These two findings must be clearly presented to patients in order to improve PCa screening acceptance

    Innovative performance of Brazilian public higher educational institutions Analysis of the remuneration of research groups and companies

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    Purpose – The purpose of this paper is to identify the compensation between research groups and companies that contribute the most for the innovative performance of Brazilian public higher educational institutions (PHEI), using as database the 2010’s tabular plan from CNPq’s Directory of Research Groups. Design/methodology/approach – Descriptive and multivariate statistical techniques such as spearman correlation, cluster analysis, ANOVA and discriminant analysis were used. Findings – Compensations that contribute the most for the updating of the PHEI are identified as transfer of financial resources from the partner to the group; providing grants for the group; transfer of material supplies to partner’s activities; temporary physical transfer of human resources from the group to the activities conducted by the partner; other forms of compensation that do not fit in the previous categories; and partnering with transfers of resources of any kind going in any direction. Research limitations/implications – As a limitation, it is pointed out the discontinuity of the tabular plan, which presents 2010 as the last available data. Practical implications – The results can contribute to programs and policies to encourage innovation within universities. Originality/value – It may be inferred that the stimulus to specific compensations may expand the quantitative idea of interaction points between the university and companies, linking qualitative aspects, which leads to an understanding that such interactions may, in fact, contribute directly to the activity of generating and spreading knowledge and innovatio

    ID-Care: a Model for Sharing Wide Healthcare Data

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    All over the world, there is a lot of patient health data in different locations such as hospitals, clinics, insurance companies, and other organizations. In this sense, global identification of the patient has emerged as an everyday healthcare challenge. Governments and institutions have to prioritize satisfactory, quick, and integrated decision-making in a wide, dispersed, and global environment because of unexpected challenges like pandemics or threats. In the current scientific literature, some of the existing challenges include support for a standard global unique identification that considers privacy issues, the combination of multiple technological biometry implementations, and personal documents. Thus, we propose a decentralized software model based on blockchain and smart contracts that includes privacy, global unique person identification supporting multiple combinations of documents, and biometric data using the Global Standards 1 - GS1 healthcare industry standard. Furthermore, we defined a methodology to evaluate a hypothetical use case of this model where an integrated and standard global health data sharing personal identification is crucial. For this, we implemented the proposed model in a global-wide continent location through cloud machines, fog computing, and blockchain considering the unique patient data identification and evaluate a use case scenario based on the top 5 most globally visited tourist destinations (France, Spain, the United States of America, China, and Italy), with an approach based on this model. The results show that using a model for a global id for healthcare can help reduce costs, time, and efforts, especially in the context of health threats, where agility and financial support must be prioritized.N/

    Transcription factor CREB3L1 mediates cAMP and glucocorticoid regulation of arginine vasopressin gene transcription in the rat hypothalamus

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    BACKGROUND: Arginine vasopressin (AVP), a neuropeptide hormone that functions in the regulation of water homeostasis by controlling water re-absorption at kidneys, is synthesised in supraoptic nucleus and paraventricular nucleus of the hypothalamus. An increase in plasma osmolality stimulates secretion of AVP to blood circulation and induces AVP synthesis in these nuclei. Although studies on mechanism of AVP transcriptional regulation in hypothalamus proposed that cAMP and glucocorticoids positively and negatively regulate Avp expression, respectively, the molecular mechanisms have remained elusive. Recently, we identified CREB3L1 (cAMP-responsive element binding protein 3 like 1) as a putative transcription factor of Avp transcription in the rat hypothalamus. However the mechanism of how CREB3L1 is regulated in response of hyperosmotic stress in the neurons of hypothalamus has never been reported. This study aims to investigate effect of previously reported regulators (cAMP and glucocorticoid) of Avp transcription on transcription factor CREB3L1 in order to establish a molecular explanation for cAMP and glucocorticoids effect on AVP expression. RESULTS: The effect of cAMP and glucocorticoid treatment on Creb3l1 was investigated in both AtT20 cells and hypothalamic organotypic cultures. The expression of Creb3l1 was increased in both mRNA and protein level by treatment with forskolin, which raises intracellular cAMP levels. Activation of cAMP by forskolin also increased Avp promoter activity in AtT20 cells and this effect was blunted by shRNA mediated silencing of Creb3l1. The forskolin induced increase in Creb3l1 expression was diminished by combined treatment with dexamethasone, and, in vivo, intraperitoneal dexamethasone injection blunted the increase in Creb3l1 and Avp expression induced by hyperosmotic stress. CONCLUSION: Here we shows that cAMP and glucocorticoid positively and negatively regulate Creb3l1 expression in the rat hypothalamus, respectively, and regulation of cAMP on AVP expression is mediated through CREB3L1. This data provides the connection between CREB3L1, a newly identified transcription factor of AVP expression, with the previously proposed mechanism of Avp transcription which extends our understanding in transcription regulation of Avp in the hypothalamus

    In vitro cytotoxicity of chemical preservatives on human fibroblast cells

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    Preservatives are widely used substances that are commonly added to various cosmetic and pharmaceutical products to prevent or inhibit microbial growth. In this study, we compared the in vitro cytotoxicity of different types of currently used preservatives, including methylparaben, imidazolidinyl urea (IMU), and sodium benzoate, using the human newborn fibroblast cell line CCD 1072Sk. Of the tested preservatives, only IMU induced a reduction in cell viability, as shown using the MIT assay and propidium iodide staining (IMU > methylparaben > sodium benzoate). IMU was shown to promote homeostatic alterations potentially related to the initiation of programed cell death, such as decreased mitochondrial membrane potential and caspase-3 activation, in the treated cells Methylparaben and sodium benzoate were shown to have a very low cytotoxic activity. Taken together, our results suggest that IMU induces programed cell death in human fibroblasts by a canonical intrinsic pathway via mitochondrial perturbation and subsequent release of proapoptotic factors.Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (CNPq)CAPESUniv Anhembi Morumbi, Escola Ciencias Saude, Grp Fitocomplexos & Sinalizacao Celular, Sao Paulo, SP, BrazilInst Osmol & Oleos Essenciais, Monte Verde, MG, BrazilUniv Fed Sao Paulo UNIFESP, EPM, Dept Farmacol, Sao Paulo, SP, BrazilUniv Mogi das Cruzes, Ctr Interdisciplinar Invest Bioquim, Sao Paulo, SP, BrazilUniv Fed Sao Paulo UNIFESP, EPM, Dept Farmacol, Sao Paulo, SP, BrazilWeb of Scienc

    In vitro cytotoxicity of chemical preservatives on human fibroblast cells

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    Preservatives are widely used substances that are commonly added to various cosmetic and pharmaceutical products to prevent or inhibit microbial growth. In this study, we compared the in vitro cytotoxicity of different types of currently used preservatives, including methylparaben, imidazolidinyl urea (IMU), and sodium benzoate, using the human newborn fibroblast cell line CCD1072Sk. Of the tested preservatives, only IMU induced a reduction in cell viability, as shown using the MTT assay and propidium iodide staining (IMU>;methylparaben>;sodium benzoate). IMU was shown to promote homeostatic alterations potentially related to the initiation of programed cell death, such as decreased mitochondrial membrane potential and caspase-3 activation, in the treated cells. Methylparaben and sodium benzoate were shown to have a very low cytotoxic activity. Taken together, our results suggest that IMU induces programed cell death in human fibroblasts by a canonical intrinsic pathway via mitochondrial perturbation and subsequent release of proapoptotic factors
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