50 research outputs found

    Solving k-center Clustering (with Outliers) in MapReduce and Streaming, almost as Accurately as Sequentially.

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    Center-based clustering is a fundamental primitive for data analysis and becomes very challenging for large datasets. In this paper, we focus on the popular k-center variant which, given a set S of points from some metric space and a parameter k0, the algorithms yield solutions whose approximation ratios are a mere additive term \u3f5 away from those achievable by the best known polynomial-time sequential algorithms, a result that substantially improves upon the state of the art. Our algorithms are rather simple and adapt to the intrinsic complexity of the dataset, captured by the doubling dimension D of the metric space. Specifically, our analysis shows that the algorithms become very space-efficient for the important case of small (constant) D. These theoretical results are complemented with a set of experiments on real-world and synthetic datasets of up to over a billion points, which show that our algorithms yield better quality solutions over the state of the art while featuring excellent scalability, and that they also lend themselves to sequential implementations much faster than existing ones

    Pattern of disinfectants use and their adverse effects on the consumers after COVID-19 outbreak

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    Background and objective: The aim of this study was to investigate the pattern of disinfectants use within outbreak of COVID-19 and estimate their adverse effects on the consumer�s health. Methods: In this descriptive-analytical study, 1090 participants were entered into the study without age and gender limitations. A researcher-made electronic checklist containing 43 questions was applied to collect data. The checklist included three sections: demographic characteristics (8 questions), disinfection of body and non-living surfaces (21 questions), and adverse effects of disinfectants on health (15 questions). Results: 87 of participants used the incorrect proportions of water and alcohol to make this disinfectant available at home. The percentage of people with wrong proportion of sodium hypochlorite was 74.2. Approximately 42 of participants experienced at least one disorder on their hands, feet, eyes, respiratory or gastrointestinal systems after sequential uses of disinfectants. The most common disorders among the participants were found to be skin dryness (76.3), obsession (42.2), skin itching (41.2), coughing (41.1), and eyes irritation (39.5). The mean frequency of hand washing and hand disinfecting were 15.28 and 10.74 times per a day, respectively, and the clean-up in case of surfaces was 2.99 times a day. The frequency of hand washing and disinfecting in women group (16.4 and 11.2 times a day) were higher than in men (14.0 and 10.3 times a day) group. In addition, these self-care actions in married people (15.6 and 11.0 times a day) were higher compared to those in single people (14.0 and 10.6 times a day). Conclusion: Being unaware of participants with instruction for preparation and use disinfectants may harm their health. Therefore, it is suggested that the authorities provide the necessary training program for public through official media. © 2020, Springer Nature Switzerland AG

    Medical students' perceptions of the educational environment at an Iranian Medical Sciences University

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    <p>Abstract</p> <p>Background</p> <p>Students' perceptions of their educational environment have a significant impact on their behavior and academic progress. The aim of this study was to assess the perceptions of medical students concerning their educational environment at Hormozgan University of Medical Sciences in Iran.</p> <p>Methods</p> <p>In this cross-sectional study, questionnaires were distributed to 210 medical students and 182 were analyzed (response rate = 86.6%); twenty-eight questionnaires were excluded because they were incomplete or unreturned for analysis. Data were collected using a DREEM questionnaire which comprised 50 items based on the Likert scale (scores could range from 0 to 200). There were five domains to the questionnaire including students' perceptions of learning, students' perceptions of teachers, students' academic self-perceptions, students' perceptions of atmosphere and students' social self-perceptions. Data were analyzed using SPSS16 software.</p> <p>Results</p> <p>The mean age of the subjects was 21.7 years (SD = 2.7); 38.5% were male and 61.5% were female. Students' perceptions of learning, students' perceptions of teachers, students' academic self-perceptions, students' perceptions of atmosphere, students' social self-perceptions and total DREEM score were 21.2/48, 24.2/44, 15.8/32, 23.8/48, 14.5/28 and 99.6/200, respectively. There was no significant difference between male and female students in educational environment subscales, but there were significant differences between students enrolled on a basic sciences and pathophysiology course and those enrolled on a clinical course in terms of perceptions of learning, academic self-perceptions, perceptions of atmosphere and overall perceptions of educational environment (p < 0.05). The latter group rated each of the aforementioned aspects more highly than the students studying basic science and pathophysiology.</p> <p>Conclusion</p> <p>Overall, respondents assessed the educational environment as average. Therefore, improvements are required across all five domains of the educational environment.</p

    Experiences of stigma in healthcare settings among adults living with HIV in the Islamic Republic of Iran

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    <p>Abstract</p> <p>Background</p> <p>People living with HIV (PLHIV) sometimes experience discrimination. There is little understanding of the causes, forms and consequences of this stigma in Islamic countries. This qualitative study explored perceptions and experiences of PLHIV regarding both the quality of healthcare and the attitudes and behaviours of their healthcare providers in the Islamic Republic of Iran.</p> <p>Methods</p> <p>In-depth, semi-structured interviews were held with a purposively selected group of 69 PLHIV recruited from two HIV care clinics in Tehran. Data were analyzed using the content analysis approach.</p> <p>Results and discussion</p> <p>Nearly all participants reported experiencing stigma and discrimination by their healthcare providers in a variety of contexts. Participants perceived that their healthcare providers' fear of being infected with HIV, coupled with religious and negative value-based assumptions about PLHIV, led to high levels of stigma. Participants mentioned at least four major forms of stigma: (1) refusal of care; (2) sub-optimal care; (3) excessive precautions and physical distancing; and (4) humiliation and blaming. The participants' healthcare-seeking behavioural reactions to perceived stigma and discrimination included avoiding or delaying seeking care, not disclosing HIV status when seeking healthcare, and using spiritual healing. In addition, emotional responses to perceived acts of stigma included feeling undeserving of care, diminished motivation to stay healthy, feeling angry and vengeful, and experiencing emotional stress.</p> <p>Conclusions</p> <p>While previous studies demonstrate that most Iranian healthcare providers report fairly positive attitudes towards PLHIV, our participants' experiences tell a different story. Therefore, it is imperative to engage both healthcare providers and PLHIV in designing interventions targeting stigma in healthcare settings. Additionally, specialized training programmes in universal precautions for health providers will lead to stigma reduction. National policies to strengthen medical training and to provide funding for stigma-reduction programming are strongly recommended. Investigating Islamic literature and instruction, as well as requesting official public statements from religious leaders regarding stigma and discrimination in healthcare settings, should be used in educational intervention programmes targeting healthcare providers. Finally, further studies are needed to investigate the role of the physician and religion in the local context.</p

    Health-related quality of life in diabetic patients and controls without diabetes in refugee camps in the Gaza strip: a cross-sectional study

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    BACKGROUND: Prevalence of diabetes mellitus is increasing in developed and developing countries. Diabetes is known to strongly affect the health-related quality of life (HRQOL). HRQOL is also influenced by living conditions. We analysed the effects of having diabetes on HRQOL under the living conditions in refugee camps in the Gaza strip. METHODS: We studied a sample of 197 diabetic patients who were recruited from three refugee camps in the Gaza strip and 197 age- and sex-matched controls living in the same camps. To assess HRQOL, we used the World Health Organization Quality of Life questionnaire (WHOQOL-BREF) including four domains (physical health, psychological, social relations and environment). Domain scores were compared for cases (diabetic patients) and controls (persons without diabetes) and the impact of socio-economic factors was evaluated in both groups. RESULTS: All domains were strongly reduced in diabetic patients as compared to controls, with stronger effects in physical health (36.7 vs. 75.9 points of the 0–100 score) and psychological domains (34.8 vs. 70.0) and weaker effects in social relationships (52.4 vs. 71.4) and environment domains (23.4 vs. 36.2). The impact of diabetes on HRQOL was especially severe among females and older subjects (above 50 years). Low socioeconomic status had a strong negative impact on HRQOL in the younger age group (<50 years). CONCLUSION: HRQOL is strongly reduced in diabetic patients living in refugee camps in the Gaza strip. Women and older patients are especially affected

    Prediction of breast self-examination in a sample of Iranian women: an application of the Health Belief Model

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    <p>Abstract</p> <p>Background</p> <p>Iranian women, many of whom live in small cities, have limited access to mammography and clinical breast examinations. Thus, breast self examination (BSE) becomes an important and necessary approach to detecting this disease in its early stages in order to limit its resultant morbidity and mortality. This study examined constructs arising from the Health Belief Model as predictors of breast self examination behavior in a sample of women living in Bandar Abbas, Iran.</p> <p>Methods</p> <p>This study was conducted in eight health centers located in Bandar Abbas, Iran. The sample consisted of 240 eligible women who were selected from referrals to the centers. The inclusion criteria were as follows: aged 30 years and over; and able to read and write Farsi. Women with breast cancer, who were pregnant, or breast feeding, were excluded from the study. Data were collected by using a self administered questionnaire which included demographic characteristics and Champion's Health Belief Model Scale. This instrument measures the concepts of disease susceptibility (3 items), seriousness (6 items), benefits (4 items), barriers (8 items) and self-efficacy (10 items).</p> <p>Results</p> <p>The subjects' mean age was 37.2 (SD = 6.1) years. Just under a third of the subjects (31.7%) had performed BSE in the past and 7.1% of them performed it at least monthly. Perceived benefits and perceived self-efficacy of the women who performed BSE were significantly higher compared with women who did not practice BSE (p < 0.03). Furthermore, perceived barriers were lower among those who had performed BSE (p < 0.001). Logistic regression analysis indicated that women who perceived fewer barriers (OR: 0.70, 95% CI: 0.63-0.77, p < 0.001) and had higher self-efficacy (OR: 1.08, 95% CI: 1.02-1.13, p = 0.003) were more likely to perform BSE (R<sup>2 </sup>= 0.52).</p> <p>Conclusion</p> <p>Findings from this study indicated that perceived barriers and perceived self-efficacy could be predictors of BSE behavior among the sample of women. Therefore, BSE training programs that emphasize self-efficacy and address perceived barriers are recommended.</p

    Morbidity and mortality from road injuries: results from the Global Burden of Disease Study 2017

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    BackgroundThe global burden of road injuries is known to follow complex geographical, temporal and demographic patterns. While health loss from road injuries is a major topic of global importance, there has been no recent comprehensive assessment that includes estimates for every age group, sex and country over recent years.MethodsWe used results from the Global Burden of Disease (GBD) 2017 study to report incidence, prevalence, years lived with disability, deaths, years of life lost and disability-adjusted life years for all locations in the GBD 2017 hierarchy from 1990 to 2017 for road injuries. Second, we measured mortality-to-incidence ratios by location. Third, we assessed the distribution of the natures of injury (eg, traumatic brain injury) that result from each road injury.ResultsGlobally, 1 243 068 (95% uncertainty interval 1 191 889 to 1 276 940) people died from road injuries in 2017 out of 54 192 330 (47 381 583 to 61 645 891) new cases of road injuries. Age-standardised incidence rates of road injuries increased between 1990 and 2017, while mortality rates decreased. Regionally, age-standardised mortality rates decreased in all but two regions, South Asia and Southern Latin America, where rates did not change significantly. Nine of 21 GBD regions experienced significant increases in age-standardised incidence rates, while 10 experienced significant decreases and two experienced no significant change.ConclusionsWhile road injury mortality has improved in recent decades, there are worsening rates of incidence and significant geographical heterogeneity. These findings indicate that more research is needed to better understand how road injuries can be prevented
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