Research program on exposure dose reconstruction and multimedia simulation tool

Issued as Annual progress report, and Research proposal, Project E-20-X7

Studying and Modeling the Connection between People's Preferences and Content Sharing

People regularly share items using online social media. However, people's decisions around sharing---who shares what to whom and why---are not well understood. We present a user study involving 87 pairs of Facebook users to understand how people make their sharing decisions. We find that even when sharing to a specific individual, people's own preference for an item (individuation) dominates over the recipient's preferences (altruism). People's open-ended responses about how they share, however, indicate that they do try to personalize shares based on the recipient. To explain these contrasting results, we propose a novel process model of sharing that takes into account people's preferences and the salience of an item. We also present encouraging results for a sharing prediction model that incorporates both the senders' and the recipients' preferences. These results suggest improvements to both algorithms that support sharing in social media and to information diffusion models.Comment: CSCW 201

A Research of nasal methicillin resistant/sensitive Staphylococcus aureus and pharyngeal beta-haemolytic Streptococcus carriage in midwifery students in Kahramanmaras, Eastern Mediterranean Region of Turkey

Background: In the hospitals where hygienic conditions are not provided, nasal methicillin resistant/sensitive Staphylococcus aureus (MRSA/MSSA) colonization is seen in the hospital personnel and patients. Both the individuals’ themselves being MRSA/MSSA carriers and also other people around them are under risk and this bacterium leads to nasal colonization and then can propagate through contaminated hands and hospital materials.Objective: In this study, it was aimed to research MRSA/MSSA and beta-haemolytic streptococcus (BHS) carriage in the nose and throat flora of students of, School of Health.Methods: In the study, total of 160 midwifery students taking midwifery education was included in the research but 135 (84.4 %) out of 160 students were able to be reached. The nose and throat swab samples taken from students were examined through microbiological methods.Results: 14.1 % of students were nasal MSSA carrier. While there wasn't the nasal MRSA carrier among students attending the study in the 1st and 2nd class, 3.3 % (1 person) of the 3rd class students and 10.0 % (3 people) of the 4th class students were the nasal MRSA carrier. In addition, BHS carriage was determined in 1.5 % of students and there wasn't any difference between classes.Conclusions: These results indicate that midwifery students might have been contaminated with MSSA/MRSA during clinical practice. That MSSA/MRSA being an important pathogen is seen in midwifery students taking education in the birth units threatens the mother-child health. [Ethiop. J. Health Dev. 2010;24(1):57-60

Resolution limit in community detection

Detecting community structure is fundamental to clarify the link between structure and function in complex networks and is used for practical applications in many disciplines. A successful method relies on the optimization of a quantity called modularity [Newman and Girvan, Phys. Rev. E 69, 026113 (2004)], which is a quality index of a partition of a network into communities. We find that modularity optimization may fail to identify modules smaller than a scale which depends on the total number L of links of the network and on the degree of interconnectedness of the modules, even in cases where modules are unambiguously defined. The probability that a module conceals well-defined substructures is the highest if the number of links internal to the module is of the order of \sqrt{2L} or smaller. We discuss the practical consequences of this result by analyzing partitions obtained through modularity optimization in artificial and real networks.Comment: 8 pages, 3 figures. Clarification of definition of community in Section II + minor revision

Efficacy of Vancomycin, Teicoplanin and Fusidic Acid as Prophylactic Agents in Prevention of Vascular Graft Infection: An Experimental Study in Rat

AbstractObjectivesTo compare the efficacy of a single prophylactic dose of intra-peritoneal vancomycin and teicoplanin with anti-biotic treated Dacron grafts (vancomycin, teicoplanin, 10 or 40% fusidic acid-soaked grafts) in preventing vascular graft infections in a rat model.DesignProspective, randomized, controlled animal study.Materials and methodsThe graft infections were established in the subcutaneous tissues of 80 female Sprague–Dawley rats by the implantation of Dacron prostheses followed by the topical inoculation with methicillin-resistant Staphylococcus aureus. The study groups were as follows: (1) uncontaminated control group, (2) untreated contaminated group, (3) contaminated group with intra-peritoneal vancomycin, (4) contaminated group with intra-peritoneal teicoplanin, (5) contaminated group received vancomycin-soaked Dacron graft, (6) contaminated group received teicoplanin-soaked Dacron graft, (7) contaminated group received 40% fusidic acid-soaked Dacron graft, and (8) contaminated group received 10% fusidic acid-soaked Dacron graft prophylaxis. The grafts were removed after 7 days and evaluated by a quantitative culture analysis.ResultsNo infection was detected in controls. The untreated contaminated group had a high bacteria count (6.0×104CFU/cm2 Dacron graft). Groups that received intra-peritoneal vancomycin or teicoplanin had less bacterial growth (4.8×103 and 3.9×103CFU/cm2 Dacron graft, respectively). Similarly, the group that received 10% fusidic acid-soaked graft showed less bacterial growth (3.6×103CFU/cm2 Dacron graft). The groups with vancomycin-, teicoplanin- and 40% fusidic acid-soaked grafts showed no evidence of infection. Statistical analyses demonstrated that intra-peritoneal prophylactic antibiotic treatment was less effective in inhibiting bacterial growth than high concentration antimicrobial-soaking of grafts.ConclusionThe use of vancomycin-, teicoplanin- and 40% fusidic acid-soaked grafts was effective in preventing primary prosthetic vascular graft infection

Bilateral leukocoria in infant with afibrinogenemia

M Necati Demir1, Mehmet Akif Acar1, Yusuf Ziya Aral2, Nurten Ünlü11Ankara Education and Research Hospital, Department of Ophthalmology, Ankara, Turkey; 2Aydin Menderes University, Faculty of Medicine, Department of Pediatric Hematology, Aydin, TurkeyPurpose: To report a bilateral leukocoria case in a patient suffering from afibrinogenemia.Methods: An observational case where congenital afibrinogenemia was presented with bilateral retinal and vitreous hemorrhages that proceeded to vitreoretinal surgery was presented. In addition, complete ophthalmic and radiological examinations and vitreoretinal surgery were performed.Results: Right eye had a complete recovery while the left eye showed serious proliferative vitreoretinopathy and shortened retina. Three years after the surgery clinical examination showed that the right eye was aphacic with an attached retina and clear ocular media while the left eye was phtysic.Conclusion: We recommend broad clotting profile for infants suffering from vitreous or retinal hemorrhages with no obvious physical abuse. Our present case furthermore implies that afibrinogenemia can lie beneath the pathogenesis of bilateral leukocoria and should alert physician for the presence of an afibrinogenemia among several types of bleeding predispositions.Keywords: afibrinogenemia, retinal hemorrhage, vitreous hemorrhage, vitrectom

Determinants of Sexual Literacy of Senior High School Students in De La Salle University-Manila

Sexual literacy is an important aspect of the formative development of individuals as it influences their capacity to think about and act upon factors affecting the sexual aspect of their lives. However, achieving a certain level of sexual literacy is still a complex path in society, especially in prestigious schools in the Philippines such as De La Salle University Manila (DLSU-M). This study aims to assess DLSU-M Senior High School (SHS) students’ level of sexual literacy, determine factors significantly explaining it, and form statistical models based on the significant factors. Both Poisson regression models and Logistic regression models revealed significantly higher sexual literacy scores among students with Chinese ethnicity, teacher as main source of information on relationships and sex, and mother as secondary source of information on reproductive health. Furthermore, Poisson regression models also revealed that favoring Lesbian, Gay, Bisexual, Transgender, Queer and/or Questioning, Intersex, Asexual and/or Ally, and others (LGBTQIA+) rights is also a significant predictor of sexual literacy. Therefore, educators such as parents and teachers positively impact an SHS student’s sexual literacy. Their immediate environment is especially significant in honing their comprehension regarding sexual and reproductive health, thus, a more open yet secure space must be reinforced

Spreading in Social Systems: Reflections

In this final chapter, we consider the state-of-the-art for spreading in social systems and discuss the future of the field. As part of this reflection, we identify a set of key challenges ahead. The challenges include the following questions: how can we improve the quality, quantity, extent, and accessibility of datasets? How can we extract more information from limited datasets? How can we take individual cognition and decision making processes into account? How can we incorporate other complexity of the real contagion processes? Finally, how can we translate research into positive real-world impact? In the following, we provide more context for each of these open questions.Comment: 7 pages, chapter to appear in "Spreading Dynamics in Social Systems"; Eds. Sune Lehmann and Yong-Yeol Ahn, Springer Natur