12,759 research outputs found

    A FOLLOW-UP STUDY OF FIFTY-TWO RICHMOND PUBLIC SCHOOL PUPILS GIVEN PSYCHIATRIC STAFFING DURING THE 1966-1967 SCHOOL YEAR

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    This research study is a descriptive study of the effectiveness of the psychiatric staffing as determined by a follow-up study of fifty-two Richmond Public School Pupils given such staffing during the l966-67 school year. The review of pertinent literature reveals what others have contributed to the knowledge of the nature and function of the school helping team. The teamwork approach, which involves the efforts of several professions and disciplines working closely together, is seen as the best present method to meet the complex, overlapping needs which have been found to affect students\u27 learning. As a means of establishing guidelines and limits for this study, five areas of concern were defined. The questions to be answered by this study were: 1. What are the socio-economic backgrounds represented by the sample? 2. Were the recommendations made by the school psychiatrist implemented? 3. Is the overall psychiatric staffing effective according to the improvement in pupils presenting problems and the extent to which the recommendations were carried out? 4. To what extent do the available records contain sufficient information for a follow-up study? 5. What are the attitudes of the key persons responsible for the psychiatric staffing toward the effective operation of these staffings? The Pupil Personnel Services gave its approval to conduct this study. The sample numbered fifty-two. The agency requested and it was agreed that no pupil, school, or agency be contacted and that information be obtained only from the files and employees of Pupil Personnel Services. An interview schedule was constructed to elicit information to determine the extent to which the recommendations made during the psychiatric staffing were initiated and carried out. This schedule was applied to the pupil records. Open ended questions were used in interview schedules to gather pertinent information from three key persons responsible for the effective operation of the psychiatric staffing. The fifty-two pupil cases revealed the pupils to be largely from low income families, mostly males with acting-out behavior problems, and with no significant concentration from any one school. A larger percentage of the recommendations that were initiated involved the use of school resources rather than community resources. In nearly half of the pupil cases the recommendations were completely carried out, with a remaining few being carried out to a lesser extent. The findings suggested that, if the recommendations were carried out, the pupil would show behavior improvement. To a large extent the statements made by the key persons generally reflected that methods of record keeping be improved within the Department of Visiting Teachers; that there be an increase in the number and quality of the visiting teachers, especially for elementary and Junior high school placements; that parents of the pupils given psychiatric staffings become involved in the staffings and be included in the treatment process themselves; and that the visiting teacher exercise more responsibility for follow-up on the pupils given psychiatric staffing

    A Proof of Entropy Minimization for Outputs in Deletion Channels via Hidden Word Statistics

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    From the output produced by a memoryless deletion channel from a uniformly random input of known length nn, one obtains a posterior distribution on the channel input. The difference between the Shannon entropy of this distribution and that of the uniform prior measures the amount of information about the channel input which is conveyed by the output of length mm, and it is natural to ask for which outputs this is extremized. This question was posed in a previous work, where it was conjectured on the basis of experimental data that the entropy of the posterior is minimized and maximized by the constant strings 000…\texttt{000}\ldots and 111…\texttt{111}\ldots and the alternating strings 0101…\texttt{0101}\ldots and 1010…\texttt{1010}\ldots respectively. In the present work we confirm the minimization conjecture in the asymptotic limit using results from hidden word statistics. We show how the analytic-combinatorial methods of Flajolet, Szpankowski and Vall\'ee for dealing with the hidden pattern matching problem can be applied to resolve the case of fixed output length and n→∞n\rightarrow\infty, by obtaining estimates for the entropy in terms of the moments of the posterior distribution and establishing its minimization via a measure of autocorrelation.Comment: 11 pages, 2 figure

    Risk evaluations and condom use decisions of homeless youth: a multi-level qualitative investigation.

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    BackgroundHomeless youth are at higher risk for sexually transmitted infections and unwanted pregnancy than non-homeless youth. However, little is known about how they evaluate risk within the context of their sexual relationships. It is important to understand homeless youths' condom use decisions in light of their sexual relationships because condom use decisions are influenced by relationship dynamics in addition to individual attitudes and event circumstances. It is also important to understand how relationship level factors, sexual event circumstances, and individual characteristics compare and intersect.MethodsTo explore these issues, we conducted semi-structured interviews with 37 homeless youth in Los Angeles County in 2011 concerning their recent sexual relationships and analyzed the data using systematic methods of team-based qualitative data analysis.ResultsWe identified themes of risk-related evaluations and decisions at the relationship/partner, event, and individual level. We also identified three different risk profiles that emerged from analyzing how different levels of risk intersected across individual respondents. The three profiles included 1) Risk Takers, who consistently engage in risk and have low concern about consequences of risk behavior, 2) Risk Avoiders, who consistently show high concern about protection and consistently avoid risk, and 3) Risk Reactors, those who are inconsistent in their concerns about risk and protection and mainly take risks in reaction to relationship and event circumstances.ConclusionsInterventions targeting homeless youth should reflect multiple levels of risk behavior and evaluation in order to address the diversity of risk profiles. Relationship/partner-, event-, and individual-level factors are all important but have different levels of importance for different homeless youth. Interventions should be tailored to address the most important factor contributing to homeless youth reproductive needs

    A Multi Agent System for Flow-Based Intrusion Detection

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    The detection and elimination of threats to cyber security is essential for system functionality, protection of valuable information, and preventing costly destruction of assets. This thesis presents a Mobile Multi-Agent Flow-Based IDS called MFIREv3 that provides network anomaly detection of intrusions and automated defense. This version of the MFIRE system includes the development and testing of a Multi-Objective Evolutionary Algorithm (MOEA) for feature selection that provides agents with the optimal set of features for classifying the state of the network. Feature selection provides separable data points for the selected attacks: Worm, Distributed Denial of Service, Man-in-the-Middle, Scan, and Trojan. This investigation develops three techniques of self-organization for multiple distributed agents in an intrusion detection system: Reputation, Stochastic, and Maximum Cover. These three movement models are tested for effectiveness in locating good agent vantage points within the network to classify the state of the network. MFIREv3 also introduces the design of defensive measures to limit the effects of network attacks. Defensive measures included in this research are rate-limiting and elimination of infected nodes. The results of this research provide an optimistic outlook for flow-based multi-agent systems for cyber security. The impact of this research illustrates how feature selection in cooperation with movement models for multi agent systems provides excellent attack detection and classification

    Inositol phosphatase SHIP1 is a primary target of miR-155

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    MicroRNA-155 (miR-155) has emerged as a critical regulator of immune cell development, function, and disease. However, the mechanistic basis for its impact on the hematopoietic system remains largely unresolved. Because miRNAs function by repressing specific mRNAs through direct 3′UTR interactions, we have searched for targets of miR-155 implicated in the regulation of hematopoiesis. In the present study, we identify Src homology-2 domain-containing inositol 5-phosphatase 1 (SHIP1) as a direct target of miR-155, and, using gain and loss of function approaches, show that miR-155 represses SHIP1 through direct 3′UTR interactions that have been highly conserved throughout evolution. Repression of endogenous SHIP1 by miR-155 occurred following sustained over-expression of miR-155 in hematopoietic cells both in vitro and in vivo, and resulted in increased activation of the kinase Akt during the cellular response to LPS. Furthermore, SHIP1 was also repressed by physiologically regulated miR-155, which was observed in LPS-treated WT versus miR-155−/− primary macrophages. In mice, specific knockdown of SHIP1 in the hematopoietic system following retroviral delivery of a miR-155-formatted siRNA against SHIP1 resulted in a myeloproliferative disorder, with striking similarities to that observed in miR-155-expressing mice. Our study unveils a molecular link between miR-155 and SHIP1 and provides evidence that repression of SHIP1 is an important component of miR-155 biology

    Enterprise-level risk assessment of geographically diversified commercial farms: a copula approach

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    As agriculture becomes more industrialized, the role of risk measures such as value-at-risk (VaR) will become more utilized. In this case it was applied to geographical diversification and also modifying the traditional VaR estimation by incorporating a copula dependence parameter into the VaR estimation. In addition, an alternative risk measure was also calculated, CVaR. The CVaR, unlike VaR, is a coherent risk measure. Thus it does not suffer from many of the shortcomings of the VaR. The land portfolio consisted of Dryland wheat production acres in Texas, Colorado, and Montana. Three series of net returns were calculated for each region. Based on the VaR and the CVaR, the portfolio was optimized based on minimizing the expected loss based on historical net revenues. The results showed that diversification could be reduced by producing in all three areas.Copula, CVaR, Risk-Management, Geographical Diversification, Agribusiness, Farm Management, Risk and Uncertainty,

    Multi-Period Asset Allocation: An Application of Discrete Stochastic Programming

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    The issue of modeling farm financial decisions in a dynamic framework is addressed in this paper. Discrete stochastic programming is used to model the farm portfolio over the planning period. One of the main issues of discrete stochastic programming is representing the uncertainty of the data. The development of financial scenario generation routines provides a method to model the stochastic nature of the model. In this paper, two approaches are presented for generating scenarios for a farm portfolio problem. The approaches are based on copulas and optimization. The copula method provides an alternative to the multivariate normal assumption. The optimization method generates a number of discrete outcomes which satisfy specified statistical properties by solving a non-linear optimization model. The application of these different scenario generation methods is then applied to the topic of geographical diversification. The scenarios model the stochastic nature of crop returns and land prices in three separate geographic regions. The results indicate that the optimal diversification strategy is sensitive to both scenario generation method and initial acreage assumptions. The optimal diversification results are presented using both scenario generation methods.Agribusiness, Agricultural Finance, Farm Management,
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