Single photonics at telecom wavelengths using nanowire superconducting detectors

Single photonic applications - such as quantum key distribution - rely on the transmission of single photons, and require the ultimate sensitivity that an optical detector can achieve. Single-photon detectors must convert the energy of an optical pulse containing a single photon into a measurable electrical signal. We report on fiber-coupled superconducting single-photon detectors (SSPDs) with specifications that exceed those of avalanche photodiodes (APDs), operating at telecommunication wavelength, in sensitivity, temporal resolution and repetition frequency. The improved performance is demonstrated by measuring the intensity correlation function g(2)(t) of single-photon states at 1300nm produced by single semiconductor quantum dots (QDs).Comment: 7 pages, 5 figures - submitted 12 OCT 200

Factors associated with antidiabetic medication non-adherence in patients with incident comorbid depression

Aim To identify factors associated with antidiabetic drug (AD) non-adherence among patients with type 2 diabetes and depression. Study Design and Settings We conducted a population-based retrospective cohort study among new AD users with a diagnosis of depression following AD initiation. We used public health insurance data from Quebec. The dependent variable was non-adherence (i.e., < 90% of days covered by ≥ 1 AD) in the year after a depression diagnosis. Different sociodemographic, clinical and medication-related variables were assessed as potential factors of non-adherence to AD treatment. We performed univariate and multivariate logistic regressions. Results We identified 3106 new users of ADs with a diagnosis of depression between 2000 and 2006. Of these individuals, 52% were considered non-adherent to their ADs. Baseline non-adherence, younger age, the addition of another AD to the initial treatment, < 4 drug claims, visits with several different physicians, high socioeconomic status, and a small number of diabetes complications were associated with AD non-adherence. Conclusions The factors identified in the present study may help clinicians recognize patients with type 2 diabetes and incident depression at increased risk for non-adherence. In these patients, close follow-up and targeted interventions could help improve adherence to AD treatment, improve glycemic control and reduce complications

Natural fourth generation of leptons

We consider implications of a fourth generation of leptons, allowing for the most general mass patterns for the fourth generation neutrino. We determine the constraints due to the precision electroweak measurements and outline the signatures to search for at the LHC experiments. As a concrete framework to apply these results we consider the minimal walking technicolor (MWTC) model where the matter content, regarding the electroweak quantum numbers, corresponds to a fourth generation.Comment: 21 pages, 11 figures, 1 table; version to appear in JHE

GM1 Ganglioside Is A Key Factor in Maintaining the Mammalian Neuronal Functions Avoiding Neurodegeneration

Many species of ganglioside GM1, differing for the sialic acid and ceramide content, have been characterized and their physico\u2010chemical properties have been studied in detail since 1963. Scientists were immediately attracted to the GM1 molecule and have carried on an ever\u2010increasing number of studies to understand its binding properties and its neurotrophic and neuroprotective role. GM1 displays a well balanced amphiphilic behavior that allows to establish strong both hydrophobic and hydrophilic interactions. The peculiar structure of GM1 reduces the fluidity of the plasma membrane which implies a retention and enrichment of the ganglioside in specific membrane domains called lipid rafts. The dynamism of the GM1 oligosaccharide head allows it to assume different conformations and, in this way, to interact through hydrogen or ionic bonds with a wide range of membrane receptors as well as with extracellular ligands. After more than 60 years of studies, it is a milestone that GM1 is one of the main actors in determining the neuronal functions that allows humans to have an intellectual life. The progressive reduction of its biosynthesis along the lifespan is being considered as one of the causes underlying neuronal loss in aged people and severe neuronal decline in neurodegenerative diseases. In this review, we report on the main knowledge on ganglioside GM1, with an emphasis on the recent discoveries about its bioactive component

Recent developments in radiative B decays

We report on recent theoretical progress in radiative B decays. We focus on a calculation of logarithmically enhanced QED corrections to the branching ratio and forward-backward asymmetry in the inclusive rare decay anti-B --> X(s) l+ l-, and present the results of a detailed phenomenological analysis. We also report on the calculation of NNLO QCD corrections to the inclusive decay anti-B --> X(s) gamma. As far as exclusive modes are concerned we consider transversity amplitudes and the impact of right-handed currents in the exclusive anti-B --> K^* l+ l- decay. Finally, we state results for exclusive B --> V gamma decays, notably the time-dependent CP-asymmetry in the exclusive B --> K^* gamma decay and its potential to serve as a so-called ``null test'' of the Standard Model, and the extraction of CKM and unitarity triangle parameters from B --> (rho,omega) gamma and B --> K^* gamma decays.Comment: 5 pages, 2 figures. Accepted for publication in the proceedings of International Europhysics Conference on High Energy Physics (EPS-HEP2007), Manchester, England, 19-25 Jul 200

B Physics and Supersymmetry

In this talk, I briefly review a selection of SUSY effects in B physics. First, I consider models with Minimal Flavour Violation. Then I discuss SUSY models with new sources of flavour violation in squark mass matrices, analyzing present constraints and possible developments with forthcoming data on b -> s and b -> d transitions.Comment: 5 pages, uses espcrc2.sty. Contributed talk at ICHEP0

Economic evaluations of interventions to optimize medication use in older adults with polypharmacy and multimorbidity: A systematic review

Purpose: To conduct a systematic review of the economic impact of interventions intended at optimizing medication use in older adults with multimorbidity and polypharmacy. Methods: We searched Ovid-Medline, Embase, CINAHL, Ageline, Cochrane, and Web of Science, for articles published between 2004 and 2020 that studied older adults with multi-morbidity and polypharmacy. The intervention studied had to be aimed at optimizing medication use and present results on costs. Results: Out of 3,871 studies identified by the search strategy, eleven studies were included. The interventions involved different provider types, with a majority described as a multidisciplinary team involving a pharmacist and a general practitioner, in the decision-making process. Interventions were generally associated with a reduction in medication expenditure. The benefits of the intervention in terms of clinical outcomes remain limited. Five studies were cost-benefit analyses, which had a net benefit that was either null or positive. Cost-utility and cost-effectiveness analyses resulted in incremental cost-effectiveness ratios that were generally within the willingness-to-pay thresholds of the countries in which the studies were conducted. However, the quality of the studies was generally low. Omission of key cost elements of economic evaluations, including intervention cost and payer perspective, limited interpretability. Conclusion: Interventions to optimize medication use may provide benefits that outweigh their implementation costs, but the evidence remains limited. There is a need to identify and address barriers to the scaling-up of such interventions, starting with the current incentive structures for pharmacists, physicians, and patients