Signal Enhancement Based on Hölder Regularity Analysis

International audienceWe present a approach for signal enhancement based on the analysis of the local Hölder regularity. The method does not make explicit assumptions on the type of noise or on the global smoothness of the original data, but rather supposes that signal enhancement is equivalent to increasing the Hölder regularity each point. Such a scheme is well adapted to the case where the signal to be recovered is itself very irregular, e.g. nowhere differentiable with rapidly varying local regularity. In particular, we show an application to SAR image denoting where this technique yields good results compared to other algorithms

Knowledge, attitude and skills before and after a module on pharmaceutical promotion in a Nepalese medical school

<p>Abstract</p> <p>Background</p> <p>Pharmaceutical promotion is widespread and can impact prescribing by health professionals. Little research has been conducted on interactions between medical students and the pharmaceutical industry. Teaching about pharmaceutical promotion is inadequate. A survey showed that many schools spend only about two hours teaching this important topic while others spend around six hours. Recently a manual on understanding and responding to promotion has been published by Health Action International (HAI) and the World Health Organization (WHO). From April to August 2011 the department of Clinical Pharmacology at KIST Medical College, Lalitpur, Nepal conducted a module on pharmaceutical promotion for second year students based on the manual. The module used active learning strategies such as brainstorming sessions, role plays and group activities. The study worked on the hypothesis that a module on pharmaceutical promotion will be effective in improving the knowledge, attitude and skills of medical students regarding pharmaceutical promotion. The impact of the module on knowledge, attitude and skills was tested using a retrospective-pre questionnaire. The scores according to gender and method of financing of medical education before and after the module were compared using appropriate non-parametric tests.</p> <p>Results</p> <p>Eighty-seven of the 100 second year students (87%) participated in the study. 47 were females (54%) and 39 (44.83%) were males and one did not state the gender. Seventy-seven students (88.5%) were self-financing while 9 were scholarship students. The median knowledge, attitude and skills score before the module were 9, 13 and 6 respectively while the overall score was 28. The scores increased significantly to 16, 15 and 14 respectively after the module while the overall score increased to 45. The median attitude scores and total scores were significantly higher among females both before and after the module. The scores did not vary with method of financing of medical education. All scores increased significantly at the end of the module.</p> <p>Conclusions</p> <p>The nine hour module held over a period of four months was effective in improving respondents' knowledge, attitudes and skills about pharmaceutical promotion. The module was not resource intensive and used resources already available in the institution. Similar modules can be considered in other medical and health profession schools in Nepal, South Asia and other developing countries.</p

Constraints on Nucleon Decay via "Invisible" Modes from the Sudbury Neutrino Observatory

Data from the Sudbury Neutrino Observatory have been used to constrain the lifetime for nucleon decay to ``invisible'' modes, such as n -> 3 nu. The analysis was based on a search for gamma-rays from the de-excitation of the residual nucleus that would result from the disappearance of either a proton or neutron from O16. A limit of tau_inv > 2 x 10^{29} years is obtained at 90% confidence for either neutron or proton decay modes. This is about an order of magnitude more stringent than previous constraints on invisible proton decay modes and 400 times more stringent than similar neutron modes.Comment: Update includes missing efficiency factor (limits change by factor of 2) Submitted to Physical Review Letter

Selenocysteine Insertion Sequence Binding Protein 2L Is Implicated as a Novel Post-Transcriptional Regulator of Selenoprotein Expression

The amino acid selenocysteine (Sec) is encoded by UGA codons. Recoding of UGA from stop to Sec requires a Sec insertion sequence (SECIS) element in the 3′ UTR of selenoprotein mRNAs. SECIS binding protein 2 (SBP2) binds the SECIS element and is essential for Sec incorporation into the nascent peptide. SBP2-like (SBP2L) is a paralogue of SBP2 in vertebrates and is the only SECIS binding protein in some invertebrates where it likely directs Sec incorporation. However, vertebrate SBP2L does not promote Sec incorporation in in vitro assays. Here we present a comparative analysis of SBP2 and SBP2L SECIS binding properties and demonstrate that its inability to promote Sec incorporation is not due to lower SECIS affinity but likely due to lack of a SECIS dependent domain association that is found in SBP2. Interestingly, however, we find that an invertebrate version of SBP2L is fully competent for Sec incorporation in vitro. Additionally, we present the first evidence that SBP2L interacts with selenoprotein mRNAs in mammalian cells, thereby implying a role in selenoprotein expression

Prevalence and predictors of 6-month exclusive breastfeeding among Canadian women: a national survey

<p>Abstract</p> <p>Background</p> <p>In spite of the evidence supporting the importance of breastfeeding during the first year of life, data on breastfeeding practices remain limited in Canada. The study aimed to examine the prevalence and predictors of 6-month exclusive breastfeeding among Canadian women.</p> <p>Methods</p> <p>The analysis was based on the Maternity Experience Survey targeting women aged ≥ 15 years who had singleton live births between February 2006 - May 2006 in the Canadian provinces and November 2005 - February 2006 in the territories. The main outcome was exclusive breastfeeding based on the World Health Organization definition. Socioeconomic, demographic, maternal, pregnancy and delivery related variables were considered for a multivariate logistic regression using stepwise modeling. Bootstrapping was performed to account for the complex sampling design.</p> <p>Results</p> <p>The sample size in this study was 5,615 weighted to represent 66,810 Canadian women. While ever breastfeeding was 90.3%, the 6-month exclusive breastfeeding rate was 13.8%. Based on the regression model, having higher years of education, residing in the Northern territories and Western provinces, living with a partner, having had previous pregnancies, having lower pre-pregnancy body mass index and giving birth at older age were associated with increased likelihood of 6-month exclusive breastfeeding. Moreover, smoking during pregnancy, Caesarean birth, infant's admission to the intensive care unit and maternal employment status before 6 months of infant's age were negatively associated with exclusive breastfeeding. Mothers choosing to deliver at home were more likely to remain exclusively breastfeeding for 6 months (Odds Ratio: 5.29, 95% Confidence Interval: 2.95-9.46).</p> <p>Conclusions</p> <p>The 6-month exclusive breastfeeding rate is low in Canada. The study results constitute the basis for designing interventions that aim to bridge the gap between the current practices of breastfeeding and the World Health Organization recommendation.</p

The impact of genetic counselling about breast cancer risk on women's risk perceptions and levels of distress

Women referred to a familial breast cancer clinic completed questionnaires before and after counselling and at annual follow-up to assess their risk estimate and psychological characteristics. The aims were to determine whether those who attended the clinic overestimated their risk or were highly anxious and whether counselling influenced risk estimates and levels of distress. Women (n = 450) at this clinic were more likely to underestimate (39%) than overestimate (14%) their risk. Mean trait anxiety scores were higher than general population data (t = 4.9, n = 1059, P < 0.001) but not significantly different from published data from other screening samples. Overestimators (z = 5.69, P < 0.0001) and underestimators (z = –8.01, P < 0.0001) reported significantly different risk estimates (i.e. increased accuracy) after counselling, but significant inaccuracies persisted. Over- (n = 12) and underestimators (n = 60) were still inaccurate in their risk estimates by a factor of 2 after counselling. Thirty per cent of the sample scored above the cut-off (5/6) for case identification on a screening measure for psychological distress, the General Health Questionnaire (GHQ). GHQ scores were significantly lower after counselling (t = 3.6, d.f. = 384, P = 0.0004) with no evidence of increasing risk estimate causing increased distress. The risk of distress after counselling was greater for younger women and those who were more distressed at first presentation. The counselling offered was effective in increasing the accuracy of risk perceptions without causing distress to those who initially underestimated their risk. It is worrying that inaccuracies persisted, particularly as the demand for service has since reduced the consultation time offered in this clinic. Further work is needed to evaluate alternative models of service delivery using more sophisticated methods of assessing understanding of risk. © 1999 Cancer Research Campaig

Search for new phenomena in final states with an energetic jet and large missing transverse momentum in pp collisions at √ s = 8 TeV with the ATLAS detector

Results of a search for new phenomena in final states with an energetic jet and large missing transverse momentum are reported. The search uses 20.3 fb−1 of √ s = 8 TeV data collected in 2012 with the ATLAS detector at the LHC. Events are required to have at least one jet with pT > 120 GeV and no leptons. Nine signal regions are considered with increasing missing transverse momentum requirements between Emiss T > 150 GeV and Emiss T > 700 GeV. Good agreement is observed between the number of events in data and Standard Model expectations. The results are translated into exclusion limits on models with either large extra spatial dimensions, pair production of weakly interacting dark matter candidates, or production of very light gravitinos in a gauge-mediated supersymmetric model. In addition, limits on the production of an invisibly decaying Higgs-like boson leading to similar topologies in the final state are presente

Jet energy measurement with the ATLAS detector in proton-proton collisions at root s=7 TeV

The jet energy scale and its systematic uncertainty are determined for jets measured with the ATLAS detector at the LHC in proton-proton collision data at a centre-of-mass energy of √s = 7TeV corresponding to an integrated luminosity of 38 pb-1. Jets are reconstructed with the anti-kt algorithm with distance parameters R=0. 4 or R=0. 6. Jet energy and angle corrections are determined from Monte Carlo simulations to calibrate jets with transverse momenta pT≥20 GeV and pseudorapidities {pipe}η{pipe}<4. 5. The jet energy systematic uncertainty is estimated using the single isolated hadron response measured in situ and in test-beams, exploiting the transverse momentum balance between central and forward jets in events with dijet topologies and studying systematic variations in Monte Carlo simulations. The jet energy uncertainty is less than 2. 5 % in the central calorimeter region ({pipe}η{pipe}<0. 8) for jets with 60≤pT<800 GeV, and is maximally 14 % for pT<30 GeV in the most forward region 3. 2≤{pipe}η{pipe}<4. 5. The jet energy is validated for jet transverse momenta up to 1 TeV to the level of a few percent using several in situ techniques by comparing a well-known reference such as the recoiling photon pT, the sum of the transverse momenta of tracks associated to the jet, or a system of low-pT jets recoiling against a high-pT jet. More sophisticated jet calibration schemes are presented based on calorimeter cell energy density weighting or hadronic properties of jets, aiming for an improved jet energy resolution and a reduced flavour dependence of the jet response. The systematic uncertainty of the jet energy determined from a combination of in situ techniques is consistent with the one derived from single hadron response measurements over a wide kinematic range. The nominal corrections and uncertainties are derived for isolated jets in an inclusive sample of high-pT jets. Special cases such as event topologies with close-by jets, or selections of samples with an enhanced content of jets originating from light quarks, heavy quarks or gluons are also discussed and the corresponding uncertainties are determined. © 2013 CERN for the benefit of the ATLAS collaboration

Measurement of the inclusive and dijet cross-sections of b-jets in pp collisions at sqrt(s) = 7 TeV with the ATLAS detector

The inclusive and dijet production cross-sections have been measured for jets containing b-hadrons (b-jets) in proton-proton collisions at a centre-of-mass energy of sqrt(s) = 7 TeV, using the ATLAS detector at the LHC. The measurements use data corresponding to an integrated luminosity of 34 pb^-1. The b-jets are identified using either a lifetime-based method, where secondary decay vertices of b-hadrons in jets are reconstructed using information from the tracking detectors, or a muon-based method where the presence of a muon is used to identify semileptonic decays of b-hadrons inside jets. The inclusive b-jet cross-section is measured as a function of transverse momentum in the range 20 < pT < 400 GeV and rapidity in the range |y| < 2.1. The bbbar-dijet cross-section is measured as a function of the dijet invariant mass in the range 110 < m_jj < 760 GeV, the azimuthal angle difference between the two jets and the angular variable chi in two dijet mass regions. The results are compared with next-to-leading-order QCD predictions. Good agreement is observed between the measured cross-sections and the predictions obtained using POWHEG + Pythia. MC@NLO + Herwig shows good agreement with the measured bbbar-dijet cross-section. However, it does not reproduce the measured inclusive cross-section well, particularly for central b-jets with large transverse momenta.Comment: 10 pages plus author list (21 pages total), 8 figures, 1 table, final version published in European Physical Journal