114 research outputs found

    Obstacle-Resistant Deployment Algorithms for Wireless Sensor Networks

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    [[abstract]]Node deployment is an important issue in wireless sensor networks (WSNs). Sensor nodes should be efficiently deployed in a predetermined region in a low-cost and high-coverage-quality manner. Random deployment is the simplest way to deploy sensor nodes but may cause unbalanced deployment and, therefore, increase hardware costs and create coverage holes. This paper presents the efficient obstacle-resistant robot deployment (ORRD) algorithm, which involves the design of a node placement policy, a serpentine movement policy, obstacle-handling rules, and boundary rules. By applying the proposed ORRD, the robot rapidly deploys a near-minimal number of sensor nodes to achieve full sensing coverage, even though there exist unpredicted obstacles with regular or irregular shapes. Performance results reveal that ORRD outperforms the existing robot deployment mechanism in terms of power conservation and obstacle resistance and, therefore, achieves better deployment performance.[[incitationindex]]SC

    Women with endometriosis have higher comorbidities: Analysis of domestic data in Taiwan

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    AbstractEndometriosis, defined by the presence of viable extrauterine endometrial glands and stroma, can grow or bleed cyclically, and possesses characteristics including a destructive, invasive, and metastatic nature. Since endometriosis may result in pelvic inflammation, adhesion, chronic pain, and infertility, and can progress to biologically malignant tumors, it is a long-term major health issue in women of reproductive age. In this review, we analyze the Taiwan domestic research addressing associations between endometriosis and other diseases. Concerning malignant tumors, we identified four studies on the links between endometriosis and ovarian cancer, one on breast cancer, two on endometrial cancer, one on colorectal cancer, and one on other malignancies, as well as one on associations between endometriosis and irritable bowel syndrome, one on links with migraine headache, three on links with pelvic inflammatory diseases, four on links with infertility, four on links with obesity, four on links with chronic liver disease, four on links with rheumatoid arthritis, four on links with chronic renal disease, five on links with diabetes mellitus, and five on links with cardiovascular diseases (hypertension, hyperlipidemia, etc.). The data available to date support that women with endometriosis might be at risk of some chronic illnesses and certain malignancies, although we consider the evidence for some comorbidities to be of low quality, for example, the association between colon cancer and adenomyosis/endometriosis. We still believe that the risk of comorbidity might be higher in women with endometriosis than that we supposed before. More research is needed to determine whether women with endometriosis are really at risk of these comorbidities

    Smoking, Green Tea Consumption, Genetic Polymorphisms in the Insulin-Like Growth Factors and Lung Cancer Risk

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    Insulin-like growth factors (IGFs) are mediators of growth hormones; they have an influence on cell proliferation and differentiation. In addition, IGF-binding protein (IGFBP)-3 could suppress the mitogenic action of IGFs. Interestingly, tea polyphenols could substantially reduce IGF1 and increase IGFBP3. In this study, we evaluated the effects of smoking, green tea consumption, as well as IGF1, IGF2, and IGFBP3 polymorphisms, on lung cancer risk. Questionnaires were administered to obtain the subjects' characteristics, including smoking habits and green tea consumption from 170 primary lung cancer cases and 340 healthy controls. Genotypes for IGF1, IGF2, and IGFBP3 were identified by polymerase chain reaction. Lung cancer cases had a higher proportion of smoking, green tea consumption of less than one cup per day, exposure to cooking fumes, and family history of lung cancer than controls. After adjusting the confounding effect, an elevated risk was observed in smokers who never drank green tea, as compared to smokers who drank green tea more than one cup per day (odds ratio (OR) = 13.16, 95% confidence interval (CI) = 2.96–58.51). Interaction between smoking and green tea consumption on lung cancer risk was also observed. Among green tea drinkers who drank more than one cup per day, IGF1 (CA)19/(CA)19 and (CA)19/X genotypes carriers had a significantly reduced risk of lung cancer (OR = 0.06, 95% CI = 0.01–0.44) compared with IGF1 X/X carriers. Smoking-induced pulmonary carcinogenesis could be modulated by green tea consumption and their growth factor environment

    Determining the content of steel furnace slag in asphalt concrete

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    Steel furnace slag containing heavy metal components is covered by asphalt cement when it is used to replace natural aggregates in road paving. When such a pavement deteriorates as a result of wear by people and vehicles as well as washing by rain, the aggregates are worn away and the heavy metal components within can overflow on the road’s surface, forming rust spots. This phenomenon has been observed on many roads, leading the general public to question the validity of using steel furnace slag and whether this is in violation of a contract with the contractor. However, it is known from literature that such rust spots on a road surface may also be caused by natural minerals such as pyrite that are contained in natural aggregates. Unlike cement concrete, the slag cannot be separated from the mixture after hardening; however, the asphalt cement can be separated from the aggregates by using a solvent. In this study, separated aggregates are tested for pH value, magnetic attraction, and elemental composition in order to assess the usability of slag. Based on the findings and the characteristics of steel furnace slag, this paper proposes a method for detection of steel furnace slag in asphalt concrete, which is divided into two stages. In the first stage, core samples of asphalt concrete are obtained from the road site. The asphalt cement is separated from the aggregates according to AASHTO T164 and then the separated aggregates are analyzed in pH value and magnetic attraction tests. When one or both of the tests indicate steel furnace slag characteristics, that is, alkalinity or magnetism, then it is possible that the asphalt concrete sample contains steel furnace slag, and should be tested in the second stage for further confirmation. In the second stage, the separated aggregates are grinded to less than 0.075 mm (No. 200) and their elemental composition is analyzed. Based on the composition of steel furnace slag, when the analysis results indicate ≥30 % CaO and ≥10 % Fe2O3, it can be regarded that steel furnace slag has been used in the asphalt concrete
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