54,309 research outputs found

    Final-State Interactions in the Superscaling Analysis of Neutral-Current Quasielastic Neutrino Scattering

    Get PDF
    Effects of strong final-state interactions in the superscaling properties of neutral-current quasielastic neutrino cross sections are investigated using the Relativistic Impulse Approximation as guidance. First- and second-kind scaling are analyzed for neutrino beam energies ranging from 1 to 2 GeV for the cases of 12C, 16O and 40Ca. Different detection angles of the outgoing nucleon are considered in order to sample various nucleon energy regimes. Scaling of the second kind is shown to be very robust. Validity of first-kind scaling is found to be linked to the kinematics of the process. Superscaling still prevails even in the presence of very strong final-state interactions, provided that some kinematical restrains are kept, and the conditions under which superscaling can be applied to predict neutral-current quasielastic neutrino scattering are determined.Comment: 39 pages, 16 figures, accepted for publication in Phys. Rev.

    Gamma-Ray Bursts Black hole accretion disks as a site for the vp-process

    Full text link
    We study proton rich nucleosynthesis in windlike outflows from gamma-ray bursts accretion disks with the aim to determine if such outflows are a site of the vp-process. The efficacy of this vp-process depends on thermodynamic and hydrodynamic factors. We discuss the importance of the entropy of the material, the outflow rate, the initial ejection point and accretion rate of the disk. In some cases the vp-process pushes the nucleosynthesis out to A~100 and produces light p-nuclei. However, even when these nuclei are not produced, neutrino induced interactions can significantly alter the abundance pattern and cannot be neglected.Comment: 9 pages, 16 figures, accepted for publication in Phys. Rev.

    Stability mapping of bipartite tight-binding graphs with losses and gain: PT−{\cal PT}-symmetry and beyond

    Full text link
    We consider bipartite tight-binding graphs composed by NN nodes split into two sets of equal size: one set containing nodes with on-site loss, the other set having nodes with on-site gain. The nodes are connected randomly with probability pp. We give a rationale for the relevance of such "throttle/brake" coupled systems (physically open systems) to grasp the stability issues of complex networks in areas such as biochemistry, neurons or economy, for which their modelling in terms of non-hermitian Hamiltonians is still in infancy. Specifically, we measure the connectivity between the two sets with the parameter α\alpha, which is the ratio of current adjacent pairs over the total number of possible adjacent pairs between the sets. For general undirected-graph setups, the non-hermitian Hamiltonian H(γ,α,N)H(\gamma,\alpha,N) of this model presents pseudo-Hermiticity, where γ\gamma is the loss/gain strength. However, we show that for a given graph setup H(γ,α,N)H(\gamma,\alpha,N) becomes PT−{\cal PT}-symmetric. In both scenarios (pseudo-Hermiticity and PT−{\cal PT}-symmetric), depending on the parameter combination, the spectra of H(γ,α,N)H(\gamma,\alpha,N) can be real even when it is non-hermitian. Thus, we numerically characterize the average fractions of real and imaginary eigenvalues of H(γ,α,N)H(\gamma,\alpha,N) as a function of the parameter set {γ,α,N}\{\gamma,\alpha,N\}. We demonstrate, for both setups, that there is a well defined sector of the γα−\gamma\alpha-plane (which grows with NN) where the spectrum of H(γ,α,N)H(\gamma,\alpha,N) is predominantly real.Comment: 10 pages, 9 figure

    Acrylamide Production Using Encapsulated Nitrile Hydratase from \u3cem\u3ePseudonocardia thermophila\u3c/em\u3e in a Sol–gel Matrix

    Get PDF
    The cobalt-type nitrile hydratase from Pseudonocardia thermophila JCM 3095 (PtNHase) was successfully encapsulated in tetramethyl orthosilicate sol–gel matrices to produce a PtNHase:sol–gel biomaterial. The PtNHase:sol–gel biomaterial catalyzed the conversion of 600 mM acrylonitrile to acrylamide in 60 min at 35 °C with a yields of \u3e90%. Treatment of the biomaterial with proteases confirmed that the catalytic activity is due to the encapsulated enzyme and not surface bound NHase. The biomaterial retained 50% of its activity after being used for a total of 13 consecutive reactions for the conversion of acrylonitrile to acrylamide. The thermostability and long-term storage of the PtNHase:sol–gel are substantially improved compared to the soluble NHase. Additionally, the biomaterial is significantly more stable at high concentrations of methanol (50% and 70%, v/v) as a co-solvent for the hydration of acrylonitrile than native PtNHase. These data indicate that PtNHase:sol–gel biomaterials can be used to develop new synthetic avenues involving nitriles as starting materials given that the conversion of the nitrile moiety to the corresponding amide occurs under mild temperature and pH conditions

    Building Neuro-Inclusive Community, Strengthening Mental Health: The Autism After 21 Utah Project

    Get PDF
    Over two decades of research shows strong positive relationships are a consistently powerful indicator of wellbeing and resilience. However, the U.S. Surgeon General notes that loneliness and isolation is an epidemic in the U.S., and that it is exacerbated for individuals with physical and mental disabilities as well as those with isolating economic or environmental situations. A recent review shows that many autistic adults in particular face challenges in finding the connections they want and need. They also often have compounding mental health conditions, such as depression and mental illness, lower incomes, isolating home environments due to a lack of resources, and significantly higher incidence of suicide deaths compared to non-autistic adults. However, there is still very little research on autistic adults, especially research that focuses on their wellbeing and that brings in their first-hand perspective. The current Autism After 21 Utah (AA21 Utah) study addresses these gaps and reveals some positive news about Utah’s readiness to build more neuro-inclusive communities to facilitate friendship and belonging, as well as some challenges that autistic adults are currently struggling with in social relationships and finding resources. The researchers surveyed 133 autistic adults, family members, and community leaders across Utah regarding needs and barriers to greater community inclusion. Twenty-four participants also volunteered to be interviewed for more in-depth perspectives; eight of the interviewees and half of the survey respondents were self-advocates. Friendship and belonging were ranked as the second-greatest unmet need for community inclusion among autistic adults and their families. Forty-three percent of participants indicated that friendship and belonging were lacking from their lives. The AA21 Utah study advocates for a community-based approach to inclusion and suggests strategies for improving autistic adults’ access to friendship and belonging. Further research is needed to determine the best methods for ensuring social belonging and friendship for autistic adults and individuals with I/DD. The AA21 Utah study researchers plan to address these methods in upcoming phases of the project

    Bose-Einstein Condensation of 88^{88}Sr Through Sympathetic Cooling with 87^{87}Sr

    Get PDF
    We report Bose-Einstein condensation of 88^{88}Sr, which has a small, negative s-wave scattering length (a88=−2a_{88}=-2\,a0a_0). We overcome the poor evaporative cooling characteristics of this isotope by sympathetic cooling with 87^{87}Sr atoms. 87^{87}Sr is effective in this role in spite of the fact that it is a fermion because of the large ground state degeneracy arising from a nuclear spin of I=9/2I=9/2, which reduces the impact of Pauli blocking of collisions. We observe a limited number of atoms in the condensate (Nmax≈104N_{max}\approx 10^4) that is consistent with the value of a88a_{88} and the optical dipole trap parameters.Comment: 4 pages, 4 figure

    A Novel Low-Cost Sensor Prototype for Nocturia Monitoring in Older People

    Get PDF
    Indexación: Scopus.This work was supported in part by CORFO - CENS 16CTTS-66390 through the National Center on Health Information Systems, in part by the National Commission for Scientific and Technological Research (CONICYT) through the program STIC-AMSUD 17STIC-03: ‘‘e-MONITOR âĂŞ Chronic Disease: Ambient Assisted Living and vital teleMONOTORing for e-health,’’ FONDEF ID16I10449 ‘‘Sistema inteligente para la gestión y análisis de la dotación de camas en la red asistencial del sector público,’’ and MEC80170097 ‘‘Red de colaboración científica entre universidades nacionales e internacionales para la estructuración del doctorado y magister en informática médica en la Universidad de Valparaíso.’’ The work of V. H. C. de Albuquerque was supported by the Brazilian National Council for Research and Development (CNPq) under Grant #304315/2017-6.Nocturia is frequently defined as the necessity to get out of bed at least one time during the night to urinate, with each of these episodes being preceded and continued by sleep. Several studies suggest that an increase of nocturia is seen with the onset of age, occurring in around 70% of adults over the age of 70. Its appearance is associated with detrimental quality of life for those who present nocturia, since it leads to daytime sleepiness, cognitive dysfunction, among others. Currently, a voiding diary is necessary for nocturia assessment; these are prone to bias due to their inherent subjectivity. In this paper, we present the design of a low-cost device that automatically detects micturition events. The device obtained 73% in sensibility and 81% in specificity; these results show that systems such as the proposed one can be a valuable tool for the medical team when evaluating nocturia. © 2013 IEEE.https://ieeexplore.ieee.org/document/845445
    • …
    corecore