1,443 research outputs found

    Estimates of future automated space mission models for use in NASA launch vehicle planning

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    Mission models for 1971 to 1981 for use in NASA launch vehicle plannin

    Telling a trusted adult: Factors associated with the likelihood of disclosing child sexual abuse prior to and during a forensic interview

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    Background: Many child sexual abuse (CSA) survivors delay or withhold disclosure of their abuse, even when presenting for formal investigation interviews. Objective: This study examined factors that relate to the CSA disclosure process. Participants and Settings: Participants were CSA victims (N = 1,732) presenting to a Child Advocacy Center (CAC) for a forensic interview. Method: We tested a structural model to predict disclosure before and during a forensic interview using secondary data analysis. Results: Youth were less likely to disclose before a forensic interview if they witnessed domestic violence (β = -.233, p \u3c .05). Caregivers were less likely to believe the abuse allegation if the alleged perpetrator resided in the home β = -.386, p \u3c .05) and more likely to believe if the youth made a prior disclosure (β = .286, p \u3c .05). Youth were more likely to disclose during the forensic interview if they were older (β=.388, p \u3c .05), if the alleged perpetrator resided in their home (β=.209, p \u3c .05), if they disclosed prior (β=.254, p \u3c .05), and if their caregiver believed the allegation (β=.213, p \u3c . 05). The alleged perpetrator residing in the youth’s home (β=-0.082, p\u3c.05) and making a prior disclosure (β=0.060, p\u3c.05) were both indirectly associated with forensic interview disclosure through caregiver belief. Conclusions: Findings highlight the importance of the family context and caregiver belief in the disclosure process for youth involved in formal CSA investigations

    Probabilistic Quantum Memories

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    Typical address-oriented computer memories cannot recognize incomplete or noisy information. Associative (content-addressable) memories solve this problem but suffer from severe capacity shortages. I propose a model of a quantum memory that solves both problems. The storage capacity is exponential in the number of qbits and thus optimal. The retrieval mechanism for incomplete or noisy inputs is probabilistic, with postselection of the measurement result. The output is determined by a probability distribution on the memory which is peaked around the stored patterns closest in Hamming distance to the input.Comment: Revised version to appear in Phys. Rev. Let

    Constant-time solution to the Global Optimization Problem using Bruschweiler's ensemble search algorithm

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    A constant-time solution of the continuous Global Optimization Problem (GOP) is obtained by using an ensemble algorithm. We show that under certain assumptions, the solution can be guaranteed by mapping the GOP onto a discrete unsorted search problem, whereupon Bruschweiler's ensemble search algorithm is applied. For adequate sensitivities of the measurement technique, the query complexity of the ensemble search algorithm depends linearly on the size of the function's domain. Advantages and limitations of an eventual NMR implementation are discussed.Comment: 14 pages, 0 figure

    Expanding Mental Health Consultation in Early Head Start: Recommendations for Supporting Home Visitors in Increasing Parental Engagement

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    Early Head Start strongly emphasizes the importance of intervening with the entire family to promote healthy child development. Parents, in particular, are recognized as their child’s most important teacher. While Early Head Start performance standards currently mandate mental health consultation to identify and intervene with child mental health problems, there is little direct focus on the role of consultation in managing parental mental health concerns. This is problematic given that a wide body of literature outlines the impact of parental mental health on engagement in home-based programs such as Early Head Start. Investigations within the home visiting field have also shown persistent requests from staff for further support in addressing these barriers to engagement. Mental health professionals can be instrumental in providing support and education to home visitors dealing with parental mental health concerns, although formal guidelines are generally silent on best practices for establishing and maintaining effective consultation relationships. This Dialog from the Field discusses the issues posed to family engagement by parent-related problems such as mental illness. Synthesizing experience from consultation provided to an Early Head Start program with research from the field, we present a model expanding mental health consultation to address parent and family concerns

    Psychological Distress and Revictimization Risk in Youth Victims of Sexual Abuse

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    Psychological distress, including depression and anxiety, has been associated with increased risk for sexual revictimization in youth who have experienced child sexual abuse. The present study utilized assessment information from treatment seeking youth with histories of sexual abuse to explore specific risk indicators for revictimization—risk taking, social problems, maladaptive cognitions, and posttraumatic stress—that may be indicated by self-reported distress. The relationship between initial levels of distress and change in symptoms over a 12-week course of treatment was also explored. Participants were 101 youth referred to a child-focused therapeutic group for victims of sexual abuse, 65 youth referred to an adolescent-focused group, and their non-offending caregivers. Results revealed that when combined into a distress score, depression and anxiety were associated with delinquent behaviors, interpersonal difficulties, maladaptive cognitions, and posttraumatic stress symptoms for child and adolescent group participants at presentation to treatment. Children exhibited improvement on measures of interpersonal difficulties, maladaptive cognitions, and self-reported posttraumatic stress disorder (PTSD) symptoms. Adolescents exhibited less change over time, with significant improvement on self-reported social problems and PTSD only. Higher psychological distress was associated with less improvement in regard to negative expectations of abuse impact for child group participants. The findings suggest that distress indicates the presence of specific revictimization risk indicators, helping to identify targetable symptoms for intervention. Therefore, screening for psychological distress after discovery of sexual abuse may help detect youth at higher risk for revictimization and guide treatment

    Psychological Distress and Revictimization Risk in Youth Victims of Sexual Abuse

    Get PDF
    Psychological distress, including depression and anxiety, has been associated with increased risk for sexual revictimization in youth who have experienced child sexual abuse. The present study utilized assessment information from treatment seeking youth with histories of sexual abuse to explore specific risk indicators for revictimization—risk taking, social problems, maladaptive cognitions, and posttraumatic stress—that may be indicated by self-reported distress. The relationship between initial levels of distress and change in symptoms over a 12-week course of treatment was also explored. Participants were 101 youth referred to a child-focused therapeutic group for victims of sexual abuse, 65 youth referred to an adolescent-focused group, and their non-offending caregivers. Results revealed that when combined into a distress score, depression and anxiety were associated with delinquent behaviors, interpersonal difficulties, maladaptive cognitions, and posttraumatic stress symptoms for child and adolescent group participants at presentation to treatment. Children exhibited improvement on measures of interpersonal difficulties, maladaptive cognitions, and self-reported posttraumatic stress disorder (PTSD) symptoms. Adolescents exhibited less change over time, with significant improvement on self-reported social problems and PTSD only. Higher psychological distress was associated with less improvement in regard to negative expectations of abuse impact for child group participants. The findings suggest that distress indicates the presence of specific revictimization risk indicators, helping to identify targetable symptoms for intervention. Therefore, screening for psychological distress after discovery of sexual abuse may help detect youth at higher risk for revictimization and guide treatment

    Wigner Functions and Separability for Finite Systems

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    A discussion of discrete Wigner functions in phase space related to mutually unbiased bases is presented. This approach requires mathematical assumptions which limits it to systems with density matrices defined on complex Hilbert spaces of dimension p^n where p is a prime number. With this limitation it is possible to define a phase space and Wigner functions in close analogy to the continuous case. That is, we use a phase space that is a direct sum of n two-dimensional vector spaces each containing p^2 points. This is in contrast to the more usual choice of a two-dimensional phase space containing p^(2n) points. A useful aspect of this approach is that we can relate complete separability of density matrices and their Wigner functions in a natural way. We discuss this in detail for bipartite systems and present the generalization to arbitrary numbers of subsystems when p is odd. Special attention is required for two qubits (p=2) and our technique fails to establish the separability property for more than two qubits.Comment: Some misprints have been corrected and a proof of the separability of the A matrices has been adde

    Robust control of decoherence in realistic one-qubit quantum gates

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    We present an open loop (bang-bang) scheme to control decoherence in a generic one-qubit quantum gate and implement it in a realistic simulation. The system is consistently described within the spin-boson model, with interactions accounting for both adiabatic and thermal decoherence. The external control is included from the beginning in the Hamiltonian as an independent interaction term. After tracing out the environment modes, reduced equations are obtained for the two-level system in which the effects of both decoherence and external control appear explicitly. The controls are determined exactly from the condition to eliminate decoherence, i.e. to restore unitarity. Numerical simulations show excellent performance and robustness of the proposed control scheme.Comment: 21 pages, 8 figures, VIth International Conference on Quantum Communication, Measurement and Computing (Boston, 2002

    Separability and Fourier representations of density matrices

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    Using the finite Fourier transform, we introduce a generalization of Pauli-spin matrices for dd-dimensional spaces, and the resulting set of unitary matrices S(d)S(d) is a basis for d×dd\times d matrices. If N=d1×d2×...×dbN=d_{1}\times d_{2}\times...\times d_{b} and H^{[ N]}=\bigotimes H^{% [ d_{k}]}, we give a sufficient condition for separability of a density matrix ρ\rho relative to the H[dk]H^{[ d_{k}]} in terms of the L1L_{1} norm of the spin coefficients of ρ>.\rho >. Since the spin representation depends on the form of the tensor product, the theory applies to both full and partial separability on a given space H[N]H^{[ N]}% . It follows from this result that for a prescribed form of separability, there is always a neighborhood of the normalized identity in which every density matrix is separable. We also show that for every prime pp and n>1n>1 the generalized Werner density matrix W[pn](s)W^{[ p^{n}]}(s) is fully separable if and only if s(1+pn1)1s\leq (1+p^{n-1}) ^{-1}
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