Black Hole Entropy, Topological Entropy and the Baum-Connes Conjecture in K-Theory

We shall try to exhibit a relation between black hole entropy and topological entropy using the famous Baum-Connes conjecture for foliated manifolds which are particular examples of noncommutative spaces. Our argument is qualitative and it is based on the microscopic origin of the Beckenstein-Hawking area-entropy formula for black holes, provided by superstring theory, in the more general noncommutative geometric context of M-Theory following the Connes- Douglas-Schwarz article.Comment: 17 pages, Latex, contains an important paragraph in section 2 which gives a better understandin

Deriving modified rankin scores from medical records

<p><b>Background and Purpose:</b> Modified Rankin score (mRS) is traditionally graded using a face-to-face or telephone interview. Certain stroke assessment scales can be derived from a review of a patient’s case-record alone. We hypothesized that mRS could be successfully derived from the narrative within patient case-records.</p> <p><b>Methods:</b> Sequential patients attending our cerebrovascular outpatient clinic were included. Two independent, blinded clinicians, trained in mRS, assessed case-records to derive mRS. They scored “certainty” of their grading on a 5-point Likert scale. Agreement between derived and traditional face-to-face mRS was calculated using attribute agreement analysis.</p> <p><b>Results:</b> Fifty patients with a range of disabilities were included. Case-record appraisers were poor at deriving mRS (k=0.34 against standard). Derived mRS grades showed poor agreement between observers (k=0.33). There was no relationship between certainty of derived mRS and proportion of correct grades (P=0.727).</p> <p><b>Conclusion:</b> Accurate mRS cannot be derived from standard hospital records. Direct mRS interview is still required for clinical trials.</p&gt

Smoking as a predictor of frailty: a systematic review

BACKGROUND: Evidence on longitudinal associations between smoking and frailty is scarce. The objective of this study was to systematically review the literature on smoking as a predictor of frailty changes among community-dwelling middle-aged and older population. METHODS: A systematic search was performed using three electronic databases: MEDLINE, Embase and Scopus for studies published from 2000 through May 2015. Reference lists of relevant articles, articles shown as related citations in PubMed and articles citing the included studies in Google Scholar were also reviewed. Studies were included if they were prospective observational studies investigating smoking status as a predictor and subsequent changes in frailty, defined by validated criteria among community-dwelling general population aged 50 or older. A standardised data collection tool was used to extract data. Methodological quality was examined using the Newcastle-Ottawa Scale for cohort studies. RESULTS: A total of 1020 studies were identified and systematically reviewed for their titles, abstracts and full-text to assess their eligibilities. Five studies met inclusion criteria and were included in this review. These studies were critically reviewed and assessed for validity of their findings. Despite different methodologies and frailty criteria used, four of the five studies consistently showed baseline smoking was significantly associated with developing frailty or worsening frailty status at follow-up. Although not significant, the other study showed the same trend in male smokers. It is of note that most of the estimate measures were either unadjusted or only adjusted for a limited number of important covariates. CONCLUSIONS: This systematic review provides the evidence of smoking as a predictor of worsening frailty status in community-dwelling population. Smoking cessation may potentially be beneficial for preventing or reversing frailty

Association between frailty and quality of life among community-dwelling older people: a systematic review and meta-analysis

BACKGROUND: With growing numbers of older people worldwide, improving and maintaining quality of life during the extended years of life are a major focus for healthcare providers and policymakers. Some studies have suggested frailty may be associated with worse quality of life. OBJECTIVES: To review the associations between frailty and quality of life among community-dwelling older people. METHODS: A systematic literature search was performed using five databases for cross-sectional and longitudinal studies examining associations between frailty and quality of life among community-dwelling older people published in 2000 or later. Reference lists of relevant studies were also manually searched. Authors were requested for data for a meta-analysis if necessary. Meta-analysis was attempted for studies using the same frailty criteria and quality-of-life instrument. Methodological quality, heterogeneity and publication bias were assessed. RESULTS: The systematic review identified 5145 studies, among which 11 cross-sectional studies and two longitudinal studies were included in this review. Meta-analysis including four cross-sectional studies using the Fried Phenotype and 36-Item Short Form Health Survey showed that those classified as frail and prefrail had significantly lower mental and physical quality-of-life scores than those classified as non-frail. High heterogeneity and possible publication bias were noted. CONCLUSIONS: This systematic review and meta-analysis has demonstrated the evidence of a consistent inverse association between frailty/prefrailty and quality of life among community-dwelling older people. Interventions targeted at reducing frailty may have the additional benefit of improving corresponding quality of life. More longitudinal analysis is required to determine this effect

Fruit and Vegetable Consumption and Incident Prefrailty and Frailty in Community-Dwelling Older People: The English Longitudinal Study of Ageing

Background: There is limited evidence in the literature regarding associations between fruit and vegetable consumption and risk of frailty. Objective: To examine associations between fruit and vegetable consumption and risk of incident frailty and incident prefrailty/frailty. Design: A prospective panel study. Setting and Subjects: 2634 non-frail community-dwelling men and women aged 60 years or older from the English Longitudinal Study of Ageing (ELSA). Methods: Fruit and vegetable consumption/day was measured using a self-completion questionnaire at baseline. Frailty status was measured at baseline and follow-up was based on modified frailty phenotype criteria. Four-year incident frailty was examined among 2634 robust or prefrail participants, and incident prefrailty/frailty was measured among 1577 robust participants. Results: Multivariable logistic regression models adjusted for age, gender, and other confounders showed that fruit and vegetable consumption was not associated with incident frailty risks among robust or prefrail participants. However, robust participants consuming 5–7.5 portions of 80 g per day (odds ratio (OR) = 0.56, 95% confidence interval (CI) = 0.37–0.85, p < 0.01) and 7.5–10 portions per day (OR = 0.46, 95%CI = 0.27–0.77, p < 0.01) had significantly lower risk of incident prefrailty/frailty compared with those consuming 0–2.5 portions/day, whereas those consuming 10 or more portions/day did not (OR = 1.10, 95%CI = 0.54–2.26, p = 0.79). Analysis repeated with fruit and vegetable separately showed overall similar results. Conclusions: Robust older adults without frailty who eat current U.K. government recommendations for fruit and vegetable consumption (5–10 portions/day) had significantly reduced risks of incident prefrailty/frailty compared with those who only eat small amount (0–2.5 portions/day). Older people can be advised that eating sufficient amounts of fruit and vegetable may be beneficial for frailty preventio

Frailty as a Predictor of Alzheimer Disease, Vascular Dementia, and All Dementia Among Community-Dwelling Older People: A Systematic Review and Meta-Analysis

OBJECTIVE: To perform a systematic search of the literature for currently available evidence on frailty as a predictor of dementia and to conduct a meta-analysis to synthesize the pooled risk estimates among community-dwelling older people. DESIGN: A systematic review and meta-analysis. DATA SOURCES: Embase, MEDLINE, CINAHL Plus, PsycINFO, and the Cochrane Library from 2000 to January 2016, and reference lists of relevant articles. ELIGIBILITY CRITERIA: Any studies that prospectively examined the incident risks of dementia with frailty among community-dwelling older people without language restriction. RESULTS: Of 2565 studies identified through the systematic review, 7 studies were included in this review. Of these, 4 studies reported hazard ratios (HR) of incident dementia for physical frailty defined by Cardiovascular Health Study criteria and were included in a meta-analysis. Frailty was a significant predictor of incident Alzheimer disease (4 studies: pooled HR = 1.28, 95% confidence interval (95% CI) = 1.00-1.63, P = .05), vascular dementia (2 studies: pooled HR 2.70, 95% CI 1.40-5.23, P = .003), and all dementia (3 studies: pooled HR 1.33, 95% CI 1.07-1.67, P = .01). Heterogeneity across the studies was low to modest (I(2) = 0%-51%). A random-effects meta-regression analysis showed that the female proportion of the cohort primarily mediated the association of frailty with Alzheimer disease (female proportion coefficient = 0.04, 95%CI = 0.01-0.08, P = .01). CONCLUSION: This systematic review and meta-analysis suggests that frailty was a significant predictor of Alzheimer disease, vascular dementia, and all dementia among community-dwelling older people. Frail women may have a higher risk of incident Alzheimer disease than frail men

Gut immune dysfunction through impaired innate pattern recognition receptor expression and gut microbiota dysbiosis in chronic SIV infection.

HIV targets the gut mucosa early in infection, causing immune and epithelial barrier dysfunction and disease progression. However, gut mucosal sensing and innate immune signaling through mucosal pattern recognition receptors (PRRs) during HIV infection and disease progression are not well defined. Using the simian immunodeficiency virus (SIV)-infected rhesus macaque model of AIDS, we found a robust increase in PRRs and inflammatory cytokine gene expression during the acute SIV infection in both peripheral blood and gut mucosa, coinciding with viral replication. PRR expression remained elevated in peripheral blood following the transition to chronic SIV infection. In contrast, massive dampening of PRR expression was detected in the gut mucosa, despite the presence of detectable viral loads. Exceptionally, expression of Toll-like receptor 4 (TLR4) and TLR8 was downmodulated and diverged from expression patterns for most other TLRs in the gut. Decreased mucosal PRR expression was associated with increased abundance of several pathogenic bacterial taxa, including Pasteurellaceae members, Aggregatibacter and Actinobacillus, and Mycoplasmataceae family. Early antiretroviral therapy led to viral suppression but only partial maintenance of gut PRRs and cytokine gene expression. In summary, SIV infection dampens mucosal innate immunity through PRR dysregulation and may promote immune activation, gut microbiota changes, and ineffective viral clearance

Solving Tree Problems with Category Theory

Artificial Intelligence (AI) has long pursued models, theories, and techniques to imbue machines with human-like general intelligence. Yet even the currently predominant data-driven approaches in AI seem to be lacking humans' unique ability to solve wide ranges of problems. This situation begs the question of the existence of principles that underlie general problem-solving capabilities. We approach this question through the mathematical formulation of analogies across different problems and solutions. We focus in particular on problems that could be represented as tree-like structures. Most importantly, we adopt a category-theoretic approach in formalising tree problems as categories, and in proving the existence of equivalences across apparently unrelated problem domains. We prove the existence of a functor between the category of tree problems and the category of solutions. We also provide a weaker version of the functor by quantifying equivalences of problem categories using a metric on tree problems.Comment: 10 pages, 4 figures, International Conference on Artificial General Intelligence (AGI) 201

Rigorous confidence intervals for critical probabilities

We use the method of Balister, Bollobas and Walters to give rigorous 99.9999% confidence intervals for the critical probabilities for site and bond percolation on the 11 Archimedean lattices. In our computer calculations, the emphasis is on simplicity and ease of verification, rather than obtaining the best possible results. Nevertheless, we obtain intervals of width at most 0.0005 in all cases

A Cascade Neural Network Architecture investigating Surface Plasmon Polaritons propagation for thin metals in OpenMP

Surface plasmon polaritons (SPPs) confined along metal-dielectric interface have attracted a relevant interest in the area of ultracompact photonic circuits, photovoltaic devices and other applications due to their strong field confinement and enhancement. This paper investigates a novel cascade neural network (NN) architecture to find the dependance of metal thickness on the SPP propagation. Additionally, a novel training procedure for the proposed cascade NN has been developed using an OpenMP-based framework, thus greatly reducing training time. The performed experiments confirm the effectiveness of the proposed NN architecture for the problem at hand