7,396 research outputs found

    Exploiting graphic processing units parallelism to improve intelligent data acquisition system performance in JET's correlation reflectometer

    Get PDF
    The performance of intelligent data acquisition systems relies heavily on their processing capabilities and local bus bandwidth, especially in applications with high sample rates or high number of channels. This is the case of the self adaptive sampling rate data acquisition system installed as a pilot experiment in KG8B correlation reflectometer at JET. The system, which is based on the ITMS platform, continuously adapts the sample rate during the acquisition depending on the signal bandwidth. In order to do so it must transfer acquired data to a memory buffer in the host processor and run heavy computational algorithms for each data block. The processing capabilities of the host CPU and the bandwidth of the PXI bus limit the maximum sample rate that can be achieved, therefore limiting the maximum bandwidth of the phenomena that can be studied. Graphic processing units (GPU) are becoming an alternative for speeding up compute intensive kernels of scientific, imaging and simulation applications. However, integrating this technology into data acquisition systems is not a straight forward step, not to mention exploiting their parallelism efficiently. This paper discusses the use of GPUs with new high speed data bus interfaces to improve the performance of the self adaptive sampling rate data acquisition system installed on JET. Integration issues are discussed and performance evaluations are presente

    Electron capture dissociation mass spectrometry of phosphopeptides: Arginine and phosphoserine

    Get PDF
    AbstractWe have previously shown that the presence of phosphorylation can inhibit detection of electron capture dissociation (ECD) fragments of doubly charged peptide ions. The presence of non-covalent interactions, in the form of salt-bridges or ionic hydrogen bonds, prevents the separation of fragments following backbone cleavage. Here, we show the electron capture dissociation mass spectrometry of a suite of model peptides designed to investigate the relationship between phosphoserine and arginine position, namely AApSAnRAmKA (n=0–6, m=6–0), the presence of lysine residues (AApSAAKAARAKA) and AAApSARAAAAKAAAK, and the presence of proline A(A/P)ApSARAAA(A/P)KAAAK. The latter are analogous to the peptides studied previously. The results show that the presence of phosphoserine and basic amino acid residues alone does not inhibit ECD fragmentation, even when the number of basic amino acid residues is greater than the precursor charge state. Neither did the presence of proline in the peptide sequence suppress ECD backbone cleavage. Nevertheless, the presence and relative position of the phosphorylated residue do alter the observed backbone fragmentation abundance. In addition, the presence of phosphorylation appears to inhibit cleavage within the arginine side-chain regardless of the relative position of the arginine residue. The results suggest that ECD fragmentation behaviour is dependent on the three-dimensional structure of a peptide rather than its sequence

    Recruiting Low Income Post-Partum Women into a Weight Loss Trial: In-Person versus Facebook Delivery

    Get PDF
    Several studies, such as the Diabetes Prevention Program (DPP), have provided foundational evidence for the effect of lifestyle modification interventions on diabetes prevention and weight loss. However, translating these programs to the real-world has proven difficult. There remains a need to increase the feasibility and reach of translational weight loss interventions. PURPOSE: To compare the recruitment rates of overweight low income postpartum women into a DPP-adapted behavioral weight loss program delivered in-person versus delivered via Facebook. METHODS: We compared two 8-week pilot behavioral weight loss trials; one delivered via weekly in-person group sessions and the other delivered entirely via Facebook. Both trials used the same recruitment methods: participants were overweight low income postpartum women within five Women Infants and Children (WIC) clinics in the Worcester, Massachusetts area recruited by nutritionists during routine WIC visits. Inclusion criteria included, childbirth in the previous 6 weeks to 6 months, age 18 or older, a body mass index (BMI) of \u3e 27 kg/m2, and obstetric provider approval for participation in the diet and physical activity components of the intervention. Additional eligibility criteria for the Facebook intervention included: 1) ability to use the Internet daily; 2) having a Facebook account; 3) currently using Facebook at least once per week. RESULTS: 27 and 54 women participated in the in-person and Facebook pilot trials, respectively. Among eligible women in the in-person trial, 62.1% gave permission to be contacted for the in-person trial, and 23.3% enrolled. Among eligible women in the Facebook trial, 59.7% of women agreed to be contacted, and 39.1% enrolled. CONCLUSIONS: Recruitment rates for a Facebook-based weight loss intervention were higher than rates for an in-person intervention. Future efforts are needed to increase reach of weight loss interventions among overweight and obese low income diverse women

    The discovery channel at the Neutrino Factory: νμ→ντ\nu_\mu\to\nu_\tau pointing to sterile neutrinos

    Full text link
    We study the potential of a Neutrino Factory in constraining the parameter space of a scheme with one sterile neutrino separated from three active ones by an O(1) eV^2, mass-squared difference. We present approximated analytic expressions for the oscillation probabilities, showing that the greatest sensitivity to sterile neutrinos at a Neutrino Factory can be achieved using the \nu_\mu ->\nu_\mu and the \nu_\mu ->\nu_\tau oscillations. We have studied two setups: a Neutrino Factory with 50 GeV (20 GeV) stored muons, with two detectors of the Hybrid-MIND type (a magnetized ECC next to a magnetized iron calorimeter), located at L=3000, 7500 km (L=4000, 7500 km) from the source. Four channels have been used: \nu_e -> \nu_\mu,\nu_\tau; \nu_\mu -> \nu_\mu,\nu_\tau. The relevant backgrounds, efficiencies and systematic errors have been taken into account, and we have discussed dependence of the sensitivities on the systematic errors. We have found that the 50 GeV (20 GeV) setup can constrain \sin^2 2 \theta^{(4fam)}_{13} <= 7x10^{-5} (2x10^{-4}); \theta_{34} <= 12 deg (14 deg); and \theta_{24}<= 7.5 deg (8 deg). Our results hold for any value of \Delta m^2_{Sbl} >~ 0.1 eV^2. Eventually we have shown that, if a positive signal is found, the proposed setup is able to measure simultaneously \theta_{34} and \delta_3 with a precision of few degrees and few tens of degrees, respectively, solving the so-called "intrinsic" and "sign degeneracies". Combination of \nu_\mu disappearance and of the \nu_\mu ->\nu_\tau channel, that will be called "the discovery channel", at the two baselines is able to measure at 99% CL a new CP-violating phase \delta_3 for \sin^2 2 \theta_{34} >= 0.06.Comment: [Revised version] 58 pages, 39 figures, uses elsart.cls. Several modifications were mad

    A Cross-Sectional Study of Prisoners in Mexico City Comparing Prevalence of Transmissible Infections and Chronic Diseases with That in the General Population.

    Get PDF
    ObjectivesTo describe patterns of transmissible infections, chronic illnesses, socio-demographic characteristics and risk behaviors in Mexico City prisons, including in comparison to the general population, to identify those currently needing healthcare and inform policy.Materials and methodsA cross-sectional study among 17,000 prisoners at 4 Mexico City prisons (June to December 2010). Participation was voluntary, confidential and based on informed consent. Participants were tested for HIV, Hepatitis B &amp; C, syphilis, hypertension, obesity, and, if at risk, glucose and cholesterol. A subset completed a questionnaire on socio-demographic characteristics and risk behaviors. Positive results were delivered with counseling and treatment or referral.Results76.8% (15,517/20,196) of men and 92.9% (1,779/1,914) of women participated. Complete data sets were available for 98.8%. The following prevalence data were established for transmissible infections: HIV 0.7%; syphilis: Anti-TP+/VDRL+ 2.0%; Hepatitis B: HBcAb 2.8%, HBsAg 0.15%; Anti-HCV 3.2%. Obesity: 9.5% men, 33.8% women. Compared with national age- and sex-matched data, the relative prevalence was greater for HIV and syphilis among women, HIV and Hepatitis C in men, and all infections in younger participants. Obesity prevalence was similar for women and lower among male participants. The prevalence of previously diagnosed diabetes and hypertension was lower. Questionnaire data (1,934 men, 520 women) demonstrated lower educational levels, increased smoking and substance use compared to national data. High levels of non-sterile tattooing, physical abuse and histories of sexual violence were found.ConclusionThe study identified that health screening is acceptable to Mexico City prisoners and feasible on a large-scale. It demonstrated higher prevalence of HIV and other infections compared to national data, though low rates compared to international data. Individual participants benefited from earlier diagnosis, treatment and support. The data collected will also enable the formulation of improved policy for this vulnerable group

    Programmable Integrated Photonics for Topological Hamiltonians

    Full text link
    A variety of topological Hamiltonians have been demonstrated in photonic platforms, leading to fundamental discoveries and enhanced robustness in applications such as lasing, sensing, and quantum technologies. To date, each topological photonic platform implements a specific type of Hamiltonian with inexistent or limited reconfigurability. Here, we propose and demonstrate different topological models by using the same reprogrammable integrated photonics platform, consisting of a hexagonal mesh of silicon Mach-Zehnder interferometers with phase-shifters. We specifically demonstrate a one-dimensional Su-Schrieffer-Heeger Hamiltonian supporting a localized topological edge mode and a higher-order topological insulator based on a two-dimensional breathing Kagome Hamiltonian with three corner states. These results highlight a nearly universal platform for topological models that may fast-track research progress toward applications of topological photonics and other coupled systems

    Adapting a Behavioral Weight Loss Intervention for Delivery via Facebook: A Pilot Series Among Low-Income Postpartum Women

    Get PDF
    BACKGROUND: Efforts to translate evidence-based weight loss interventions, such as the Diabetes Prevention Program (DPP), to low-income postpartum women have resulted in poor intervention attendance and high attrition. Strategies that improve engagement and retention in this population are needed to maximize the reach of evidence-based weight loss interventions. OBJECTIVE: The objective of this study was to adapt a DPP-based weight loss intervention (Fresh Start) for Facebook delivery and to evaluate its feasibility among low-income postpartum women. METHODS: This study comprised 3 single-group pilot studies where feasibility outcomes iteratively informed changes from one pilot to the next. We paralleled the in-person program for Facebook delivery by translating the protocol to a content library of Facebook posts with additional posts from lifestyle coaches. Low-income postpartum women were recruited from Women, Infants, and Children (WIC) clinics in Worcester, Massachusetts. Participants were enrolled into a 16-week weight loss intervention delivered via Facebook. During the first 8 weeks, Facebook intervention posts were delivered 2 times per day, with additional posts from coaches aiming to stimulate interaction among participants or respond to participants\u27 questions and challenges. For the following 8 weeks, posts were delivered once per day without additional coaching. Feasibility outcomes were engagement (defined by number of likes, comments, and posts measured throughout intervention delivery), acceptability, and retention (survey at follow-up and assessment completion rate, respectively). Changes in weight were also assessed at baseline and follow-up. RESULTS: Pilot 1 had a retention rate of 89% (24/27), and on average, 62% (17/27) of women actively engaged with the group each week during the 8-week coached phase. Mean weight loss was 2.6 (SD 8.64) pounds, and 79% (19/27) would recommend the program to a friend. Pilot 2 had a retention rate of 83% (20/24), and on average, 55% (13/24) of women actively engaged with the group weekly during the 8-week coached phase. Mean weight loss was 2.5 (SD 9.23) pounds, and 80% (16/24) would recommend the program to a friend. Pilot 3 had a retention rate of 88% (14/16), and on average, 67% (11/16) of women actively engaged with the group weekly during the 8-week coached phase. Mean weight loss was 7.0 (SD 11.6) pounds, and 100% (16/16) would recommend the program to a friend. CONCLUSIONS: Our findings demonstrated that a Facebook-delivered intervention was acceptable and could be feasibly delivered to low-income postpartum women. Future research is needed to evaluate the efficacy of a Facebook-delivered weight loss intervention

    A Scoping Review of Risk and Protective Factors for Negative Cannabis Use Consequences

    Get PDF
    Objective: Numerous reviews have examined risk and protective factors for alcohol-related negative consequences, but no equivalent review of risk and protective factors exists for cannabis-related negative consequences (CRNCs)-a gap filled by the present study. This scoping review examined survey-based research of risk and protective factors for CRNCs such as neglecting responsibilities, blacking out, or needing more cannabis. Methods: Three databases (PubMed, PsycINFO, and Google Scholar) were searched for peer-reviewed manuscripts published between January 1, 1990, and December 31, 2021. A qualitative synthesis was performed using the matrix method and the results were organized using the socioecological model as a framework. Results: Eighty-three studies were included in the review. There was considerable variation in measures and operationalizations of CRNCs across studies. Risk factors were identified in the intrapersonal (depression, social anxiety, PTSD, impulsivity, sensation seeking, motives, expectancies), interpersonal/community (trauma, victimization, family and peer substance use, social norms), and social/policy (education, employment, community attachment, legalization, availability of substances) domains of influence. Protective behavioral strategies were a robust protective factor for CRNCs. Males consistently reported more CRNCs than females, but there were no differences observed across race. Conclusions: Future research should identify person- and product-specific patterns of CRNCs to refine theoretical models of cannabis misuse and addiction. Public health interventions to reduce the risk of negative consequences from cannabis should consider utilizing multilevel interventions to attenuate the cumulative risk from a combination of psychological, contextual, and social influences

    Assessment of exposure determinants and exposure levels by using stationary concentration measurements and a probabilistic near-field/far-field exposure model

    Get PDF
    Background: The Registration, Evaluation, Authorization and Restriction of Chemicals (REACH) regulation requires the establishment of Conditions of Use (CoU) for all exposure scenarios to ensure good communication of safe working practices. Setting CoU requires the risk assessment of all relevant Contributing Scenarios (CSs) in the exposure scenario. A new CS has to be created whenever an Operational Condition (OC) is changed, resulting in an excessive number of exposure assessments. An efficient solution is to quantify OC concentrations and to identify reasonable worst-case scenarios with probabilistic exposure modeling. Methods: Here, we appoint CoU for powder pouring during the industrial manufacturing of a paint batch by quantifying OC exposure levels and exposure determinants. The quantification was performed by using stationary measurements and a probabilistic Near-Field/Far-Field (NF/FF) exposure model. Work shift and OC concentration levels were quantified for pouring TiO 2 from big bags and small bags, pouring Micro Mica from small bags, and cleaning. The impact of exposure determinants on NF concentration level was quantified by (1) assessing exposure determinants correlation with the NF exposure level and (2) by performing simulations with different OCs. Results: Emission rate, air mixing between NF and FF and local ventilation were the most relevant exposure determinants affecting NF concentrations. Potentially risky OCs were identified by performing Reasonable Worst Case (RWC) simulations and by comparing the exposure 95 th percentile distribution with 10% of the occupational exposure limit value (OELV). The CS was shown safe except in RWC scenario (ventilation rate from 0.4 to 1.6 1/h, 100 m 3 room, no local ventilation, and NF ventilation of 1.6 m 3/min). Conclusions: The CoU assessment was considered to comply with European Chemicals Agency (ECHA) legislation and EN 689 exposure assessment strategy for testing compliance with OEL values. One RWC scenario would require measurements since the exposure level was 12.5% of the OELV
    • …
    corecore