Regrets, I\u27ve Had a Few: When Regretful Experiences Do (and Don\u27t) Compel Users to Leave Facebook

Previous work has explored regretful experiences on social media. In parallel, scholars have examined how people do not use social media. This paper aims to synthesize these two research areas and asks: Do regretful experiences on social media influence people to (consider) not using social media? How might this influence differ for different sorts of regretful experiences? We adopted a mixed methods approach, combining topic modeling, logistic regressions, and contingency analysis to analyze data from a web survey with a demographically representative sample of US internet users (n=515) focusing on their Facebook use. We found that experiences that arise because of users\u27 own actions influence actual deactivation of their Facebook account, while experiences that arise because of others\u27 actions lead to considerations of non-use. We discuss the implications of these findings for two theoretical areas of interest in HCI: individual agency in social media use and the networked dimensions of privacy

Kappa-symmetric SL(2,R) covariant D-brane actions

A superspace formulation of IIB supergravity which includes the field strengths of the duals of the usual physical one, three and five-form field strengths as well as the eleven-form field strength is given. The superembedding formalism is used to construct kappa-symmetric SL(2,R) covariant D-brane actions in an arbitrary supergravity background.Comment: 20 pages. Minor clarification in text. References adde

Evaluation de l'impact bioclinique et social, individuel et collectif, du traitement ARV chez des patients VIH-1 pris en charge depuis 10 ans dans le cadre de l'ISAARV : cohorte ANRS 1215 : rapport final

This report presents the results from studies conducted between 2009 and 2011 in Senegal in the framework of the ANRS 1215 research program aimed at documenting the long-term impact of therapeutic treatment with antiretroviral drugs. The 400 participants from ANRS cohort 1215 began treatment between 1998 and 2002; they were among the first people living with HIV in Africa to receive ARV therapies. These studies were conducted using a multidisciplinary approach. The main themes are: - Medical science: immune restoration among patients who were the most immunocompromised, virologic failure and resistance mutations, changes in treatment efficacy and mortality, a description of comorbidities, an investigation of the effects of aging, and sexual health. - Public health and epidemiology: changes in treatment adherence, socioeconomic outcomes for patients, sociomedical conditions and determinants for treatment failure, and mental health. - Social sciences: patient's experience of the disease and treatment over the long term, social aspects of childbearing for HIV-positive women on ARVs, perceptions and practices related to prevention of sexual transmission of HIV for patients on ARVs, perceptions of lipodystrophy, vulnerability among widows and the aged, critical analysis of the degree of stigmatization, cost analysis of treatment and drugs, and systems for ethical research. Each of these themes led to specific, often overlapping, studies that used a complementary approach. This report is organized into five sections, with a standardized format for writing conventions, presentation, and bylines, according to the uses in the dominant disciplinary field for each part.Ce rapport rassemble les résultats des études réalisées entre 2009 et 2011 au Sénégal dans le cadre du programme de recherche ANRS 1215 qui avait pour objectif de documenter l'impact à long terme de la prise en charge thérapeutique par les médicaments antirétroviraux. Les 400 participants de la cohorte ANRS 1215 ont débuté leur traitement entre 1998 et 2002, ils font partie des premières personnes vivant avec le VIH en Afrique à avoir reçu des traitements ARV. Ces études ont été menées dans une perspective pluridisciplinaire. Les principales thématiques sont : - en sciences médicales : la restauration immunologique chez les patients les plus immunodéprimés, les échecs virologiques et les mutations de résistances, l'évolution de l'efficacité thérapeutique et de la mortalité, la description des co-morbidités, l'étude des effets du vieillissement, et la santé sexuelle. - en santé publique et épidémiologie : l'évolution de l'observance thérapeutique, le devenir socio-économique des patients, les conditions et déterminants socio-médicaux des échecs thérapeutiques, la santé mentale. - en sciences sociales : l'expérience de la maladie et du traitement à long terme, les aspects sociaux de la procréation chez les femmes vivant avec le VIH traitées par ARV, les perceptions et pratiques relatives à la prévention de la transmission sexuelle du VIH chez les patients traités par ARV, la perception des lipodystrophies, la vulnérabilité des veuves et des personnes âgées, l'analyse critique de la mesure de la stigmatisation, l'étude des coûts de prise en charge et des médicaments, les dispositifs éthiques de la recherche. Chacun de ces thèmes a conduit à des investigations spécifiques, le plus souvent associées, dans des approches visant la complémentarité. Ce rapport est organisé en cinq parties, ayant une cohérence interne au plan des conventions de rédaction, de présentation et de signatures, suivant les usages des champs disciplinaires dominants dans chaque partie

Q7-branes and their coupling to IIB supergravity

We show how, by making use of a new basis of the IIB supergravity axion-dilaton coset, SL(2,R)/SO(2), 7-branes that belong to different conjugacy classes of the duality group SL(2,R) naturally couple to IIB supergravity with appropriate source terms characterized by an SL(2,R) charge matrix Q. The conjugacy classes are determined by the value of the determinant of Q. The (p,q) 7-branes are the branes in the conjugacy class detQ = 0. The 7-branes in the conjugacy class detQ > 0 are labelled by three numbers (p,q,r) which parameterize the matrix Q and will be called Q7-branes. We construct the full bosonic Wess--Zumino term for the Q7-branes. In order to realize a gauge invariant coupling of the Q7-brane to the gauge fields of IIB supergravity it is necessary to introduce an SL(2,R) doublet of two distinct Born--Infeld fields on the Q7-brane world-volume.Comment: 31 pages, Latex fil

Practice variation in the conservative and surgical treatment of chronic subdural hematoma

Objective: Chronic subdural hematoma (CSDH) is a condition that is frequently seen in the neurological and neurosurgical practice. Surgical treatment is overall preferred; however, conservative treatment is also an option. Both surgical and conservative treatment of CSDH vary across neurosurgeons. The aim of the present study was to evaluate different treatment strategies for CSDH among neurosurgeons in different countries. Material and Methods: We designed a survey that was sent to neurosurgeons affiliated with the Congress of Neurological Surgeons.The questions were related to the conservative and surgical treatment methods of CSDH. Furthermore, we also included questions related to post-operative care. Results: 443 neurosurgeons completed the survey. 46.2 % of the respondents sometimes use dexamethasone as monotherapy. Overall, 26.2 % estimated dexamethasone to have a high efficacy on CSDH. A Glas

Supporting Accurate Interpretation of Self-Administered Medical Test Results for Mobile Health: Assessment of Design, Demographics, and Health Condition

Background: Technological advances in personal informatics allow people to track their own health in a variety of ways, representing a dramatic change in individuals’ control of their own wellness. However, research regarding patient interpretation of traditional medical tests highlights the risks in making complex medical data available to a general audience. Objective: This study aimed to explore how people interpret medical test results, examined in the context of a mobile blood testing system developed to enable self-care and health management. Methods: In a preliminary investigation and main study, we presented 27 and 303 adults, respectively, with hypothetical results from several blood tests via one of the several mobile interface designs: a number representing the raw measurement of the tested biomarker, natural language text indicating whether the biomarker’s level was low or high, or a one-dimensional chart illustrating this level along a low-healthy axis. We measured respondents’ correctness in evaluating these results and their confidence in their interpretations. Participants also told us about any follow-up actions they would take based on the result and how they envisioned, generally, using our proposed personal health system. Results: We find that a majority of participants (242/328, 73.8%) were accurate in their interpretations of their diagnostic results. However, 135 of 328 participants (41.1%) expressed uncertainty and confusion about their ability to correctly interpret these results. We also find that demographics and interface design can impact interpretation accuracy, including false confidence, which we define as a respondent having above average confidence despite interpreting a result inaccurately. Specifically, participants who saw a natural language design were the least likely (421.47 times, P=.02) to exhibit false confidence, and women who saw a graph design were less likely (8.67 times, P=.04) to have false confidence. On the other hand, false confidence was more likely among participants who self-identified as Asian (25.30 times, P=.02), white (13.99 times, P=.01), and Hispanic (6.19 times, P=.04). Finally, with the natural language design, participants who were more educated were, for each one-unit increase in education level, more likely (3.06 times, P=.02) to have false confidence. Conclusions: Our findings illustrate both promises and challenges of interpreting medical data outside of a clinical setting and suggest instances where personal informatics may be inappropriate. In surfacing these tensions, we outline concrete interface design strategies that are more sensitive to users’ capabilities and conditions

Pumping in quantum dots and non-Abelian matrix Berry phases

We have investigated pumping in quantum dots from the perspective of non-Abelian (matrix) Berry phases by solving the time dependent Schr{\"o}dinger equation exactly for adiabatic changes. Our results demonstrate that a pumped charge is related to the presence of a finite matrix Berry phase. When consecutive adiabatic cycles are performed the pumped charge of each cycle is different from the previous ones

An index for the Dirac operator on D3 branes with background fluxes

We study the problem of instanton generated superpotentials in Calabi-Yau orientifold compactifications directly in type IIB string theory. To this end, we derive the Dirac equation on a Euclidean D3 brane in the presence of background fluxes. We propose an index which governs whether the generation of a superpotential in the effective 4d theory by D3 brane instantons is possible. Applying the formalism to various classes of examples, including the K3 x T^2/Z_2 orientifold, in the absence and presence of fluxes, we show that our results are consistent with conclusions attainable via duality from an M-theory analysis.Comment: Fermion coupling to five-form restored, conclusions of the paper unchange

Self-Obviating Systems and their Application to Sustainability

Most research in computing and information science reinforces the premise that information and communications technology (ICT) can be productively applied even more broadly than it is at present. A recent thread of research in sustainable HCI, however, has focused on the possibility that there are many situations where less ICT, not more, may be desirable. We envision an adaptation of this premise, where the goal is not just to consciously omit or remove ICT systems, but rather to create systems explicitly designed to make themselves superfluous through their use. Such a system—one in which the successful operation of the system in the short term renders it superfluous in the long term—could be called a “self-obviating system”. We present a case study in the sustainable food domain for a context in which self-obviating systems could be useful, and a typology of self-obviating systems that could be relevant to other domains. Self-obviating systems could be an important part of a sustainable future, and could be applied more broadly in ICT design.ye