610 research outputs found

    A Second Look at DNS QNAME Minimization

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    The Domain Name System (DNS) is a critical Internet infrastructure that translates human-readable domain names to IP addresses. It was originally designed over 35 years ago and multiple enhancements have since then been made, in particular to make DNS lookups more secure and privacy preserving. Query name minimization (qmin) was initially introduced in 2016 to limit the exposure of queries sent across DNS and thereby enhance privacy. In this paper, we take a look at the adoption of qmin, building upon and extending measurements made by De Vries et al. in 2018. We analyze qmin adoption on the Internet using active measurements both on resolvers used by RIPE Atlas probes and on open resolvers. Aside from adding more vantage points when measuring qmin adoption on open resolvers, we also increase the number of repetitions, which reveals conflicting resolvers – resolvers that support qmin for some queries but not for others. For the passive measurements at root and Top-Level Domain (TLD) name servers, we extend the analysis over a longer period of time, introduce additional sources, and filter out non-valid queries. Furthermore, our controlled experiments measure performance and result quality of newer versions of the qmin -enabled open source resolvers used in the previous study, with the addition of PowerDNS. Our results, using extended methods from previous work, show that the adoption of qmin has significantly increased since 2018. New controlled experiments also show a trend of higher number of packets used by resolvers and lower error rates in the DNS queries. Since qmin is a balance between performance and privacy, we further discuss the depth limit of minimizing labels and propose the use of a public suffix list for setting this limit

    Statins and muscle pain

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    Introduction: Statins remain among the most frequently prescribed drugs and constitute a cornerstone in the prevention of cardiovascular disease. However, muscle symptoms are often reported from patients on statins. Muscle symptoms are frequently reported as adverse events associated with statin therapy.Areas covered: In the present narrative review, statin-associated muscle pain is discussed. It elucidates potential mechanisms and possible targets for management.Expert opinion: In general, the evidence in support of muscle pain caused by statins is in some cases equivocal and not particularly strong. Reported symptoms are difficult to quantify. Rarely is it possible to establish a causal link between statins and muscle pain. In randomized controlled trials, statins are well tolerated, and muscle-pain related side-effects is similar to placebo. There are also nocebo effects of statins. Exchange of statin may be beneficial although all statins have been associated with muscle pain. In some patients reduction of dose is worth trying, especially in primary prevention Although the benefits of statins outweigh potential risks in the vast majority of cases, careful clinical judgment may be necessary in certain cases to manage potential side effects on an individual basis

    The influence of school on whether girls develop eating disorders.

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    BACKGROUND: Clinical anecdote suggests that rates of eating disorders (ED) vary between schools. Given their high prevalence and mortality, understanding risk factors is important. We hypothesised that rates of ED would vary between schools, and that school proportion of female students and proportion of parents with post-high school education would be associated with ED, after accounting for individual characteristics. METHOD: Multilevel analysis of register-based, record-linkage data on 55 059 females born in Stockholm County, Sweden, from 1983, finishing high school in 2002-10. Outcome was clinical diagnosis of an ED, or attendance at a specialist ED clinic, aged 16-20 years. RESULTS: The 5-year cumulative incidence of ED diagnosis aged 16-20 years was 2.4%. Accounting for individual risk factors, with each 10% increase in the proportion of girls at a school, the odds ratio for ED was 1.07 (1.01 to 1.13), P = 0.018. With each 10% increase in the proportion of children with at least one parent with post-high school education, the odds ratio for ED was 1.14 (1.09 to 1.19), P < 0.0001. Predicted probability of an average girl developing an ED was 1.3% at a school with 25% girls where 25% of parents have post-high school education, and 3.3% at a school with 75% girls where 75% of parents have post-high school education. CONCLUSIONS: Rates of ED vary between schools; this is not explained by individual characteristics. Girls at schools with high proportions of female students, and students with highly educated parents, have higher odds of ED regardless of individual risk factors

    Fitting Neuron Models to Spike Trains

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    Computational modeling is increasingly used to understand the function of neural circuits in systems neuroscience. These studies require models of individual neurons with realistic input–output properties. Recently, it was found that spiking models can accurately predict the precisely timed spike trains produced by cortical neurons in response to somatically injected currents, if properly fitted. This requires fitting techniques that are efficient and flexible enough to easily test different candidate models. We present a generic solution, based on the Brian simulator (a neural network simulator in Python), which allows the user to define and fit arbitrary neuron models to electrophysiological recordings. It relies on vectorization and parallel computing techniques to achieve efficiency. We demonstrate its use on neural recordings in the barrel cortex and in the auditory brainstem, and confirm that simple adaptive spiking models can accurately predict the response of cortical neurons. Finally, we show how a complex multicompartmental model can be reduced to a simple effective spiking model

    Inhibitory effects of orthosilicic acid on osteoclastogenesis in RANKL-stimulated RAW264.7 cells.

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    Funder: Swedish Dental SocietyNumerous studies have reported on the positive effects of silicon (Si) on bone metabolism, particularly on the stimulatory effects of Si on osteoblast cells and on bone formation. Inhibitory effects of Si on osteoclast formation and bone resorption have also been demonstrated in vitro and are suggested to be mediated indirectly via stromal and osteoblast cells. Direct effects of Si on osteoclasts have been less studied and mostly using soluble Si, but no characterisation of the Si treatment solutions are provided. The aims of the present study were to (a) further investigate the direct inhibitory effects of Si on osteoclastogenesis in RANKL-stimulated RAW264.7 cells, (b) determine at what stage during osteoclastogenesis Si acts upon, and (c) determine if these effects can be attributed to the biologically relevant soluble orthosilicic acid specie. Our results demonstrate that silicon, at 50 μg/ml (or 1.8 mM), does not affect cell viability but directly inhibits the formation of TRAP+ multinucleated cells and the expression of osteoclast phenotypic genes in RAW264.7 cells. The inhibitory effect of Si was clearly associated with the early stages (first 24 hr) of osteoclastogenesis. Moreover, these effects can be attributed to the soluble orthosilicic acid specie

    Robust, accurate stochastic optimization for variational inference

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    We consider the problem of fitting variational posterior approximations using stochastic optimization methods. The performance of these approximations depends on (1) how well the variational family matches the true posterior distribution, (2) the choice of divergence, and (3) the optimization of the variational objective. We show that even in the best-case scenario when the exact posterior belongs to the assumed variational family, common stochastic optimization methods lead to poor variational approximations if the problem dimension is moderately large. We also demonstrate that these methods are not robust across diverse model types. Motivated by these findings, we develop a more robust and accurate stochastic optimization framework by viewing the underlying optimization algorithm as producing a Markov chain. Our approach is theoretically motivated and includes a diagnostic for convergence and a novel stopping rule, both of which are robust to noisy evaluations of the objective function. We show empirically that the proposed framework works well on a diverse set of models: it can automatically detect stochastic optimization failure or inaccurate variational approximation.https://papers.nips.cc/paper/2020/file/7cac11e2f46ed46c339ec3d569853759-Paper.pdfPublished versio
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