10,192 research outputs found

    Evidence of Program Quality and Youth Outcomes in the DYCD Out-of-School Time Initiative: Report on the Initiative's First Three Years

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    Examines New York City's progress in improving out-of-school-time program quality and serving more children and youth, participants' and parents' overall satisfaction with quality and accessibility, and links between programming, quality, and benefits

    Spin and magnetism in old neutron stars

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    The thermal, spin and magnetic evolution of neutron stars in the old low mass binaries is first explored. Recycled to very short periods via accretion torques, the neutron stars lose their magnetism progressively. If accretion proceeds undisturbed for 100 Myrs these stars can rotate close to break up with periods far below the minimum observed of 1.558 ms. We investigate their histories using population synthesis models to show that a tail should exist in the period distribution below 1.558 ms. The search of these ultrafastly spinning neutron stars as pulsars can help discriminating among the various equations of state for nuclear matter, and can shed light into the physics of binary evolution. The evolution of isolated neutron stars in the Galaxy is explored beyond the pulsar phase. Moving through the tenuous interstellar medium, these old solitary neutron stars lose their rotational energy. Whether also their magnetism fades is still a mystery. A population synthesis model has revealed that only a tiny fraction of them is able to accrete from the interstellar medium, shining in the X-rays. There is the hope that these solitary stars will eventually appear as faint sources in the Chandra sky survey. This might give insight on the long term evolution of the magnetic field in isolated objects.Comment: 28 pages, 11 PostScript figures. To be published in "Physics of Neutron Star Interiors" (Lecture Notes in Physics), ed. D. Blaschke, N.K. Glendenning and A. Sedrakian (Springer, 2001

    Investigating the Presence of Regional Economic Growth Convergence in the Philippines using Kalman Filter

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    This paper investigates the presence of stochastic and dynamic convergence of the 14 regional economies in the Philippines in terms of per capita Gross Regional Domestic Product (GRDP) using regional panel data from 1988 to 2007. Stochastic convergence, which indicates convergence of regions in the long-run, is tested using Levin, Lin & Chu (LLC) and Im, Pesaran & Shin (IPS) panel unit root tests. The presence of convergence, on one hand, indicates that the economically laggard regions are gaining on the economically better-performing regions with respect to per capita GRDP. On the other hand, the lack of convergence indicates a need to reevaluate existing regional and national economic policies on development. Dynamic convergence reveals several convergence characteristics of individual regions over time. Dynamic convergence is determined by the time-varying parameter (TVP) model derived using the Kalman Filter. The paper proceeds to examine the individual convergence behavior of each region based on the value of the estimate of the parameter of the TVP. The results show that out of the 14 regions studied, seven regions are found to converge towards the average of the national per capita GDP growth rate over 1988 to 2007 while six regions lag behind the average of the national per capita GDP growth rate over the same period. No region converges towards the economic growth rate of National Capital Region, the lead region used in the study.Panel Unit Root Test, Time-varying Parameter (TVP) Model, Kalman Filter, Stochastic Convergence, Dynamic Convergence

    Are cocaine-seeking “habits” necessary for the development of addiction-like behavior in rats?

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    Drug self-administration models of addiction typically require animals to make the same response (e.g., a lever-press or nose-poke) over and over to procure and take drugs. By their design, such procedures often produce behavior controlled by stimulus-response (S-R) habits. This has supported the notion of addiction as a “drug habit”, and has led to considerable advances in our understanding of the neurobiological basis of such behavior. However, for addicts to procure drugs, like cocaine, often requires considerable ingenuity and flexibility in seeking behavior, which, by definition, precludes the development of habits. To better model drug-seeking behavior in addicts we first developed a novel cocaine self-administration procedure (the Puzzle Self-Administration Procedure; PSAP) that required rats to solve a new puzzle every day to gain access to cocaine, which they then self-administered on an Intermittent Access (IntA) schedule. Such daily problem-solving precluded the development of S-R seeking habits. We then asked whether prolonged PSAP/IntA experience would nevertheless produce ‘symptoms of addiction’. It did, including escalation of intake, sensitized motivation for drug, continued drug use in the face of adverse consequences and very robust cue-induced reinstatement of drug-seeking, especially in a subset of ‘addiction-prone’ rats. Furthermore, drug-seeking behavior continued to require dopamine neurotransmission in the core of the nucleus accumbens (but not the dorsolateral striatum). We conclude that the development of S-R seeking habits is not necessary for the development of cocaine addiction-like behavior in rats

    Transcriptomic effects of the non-steroidal anti-inflammatory drug Ibuprofen in the marine bivalve Mytilus galloprovincialis Lam

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    The transcriptomic effects of Ibuprofen (IBU) in the digestive gland tissue of Mytilus galloprovincialis Lam. specimens exposed at low environmental concentrations (250 ng L-1) are presented. Using a 1.7 K feature cDNA microarray along with linear models and empirical Bayes statistical methods 225 differentially expressed genes were identified in mussels treated with IBU across a 15-day period. Transcriptional dynamics were typical of an adaptive response with a peak of gene expression change at day 7 (177 features, representing about 11% of sequences available for analysis) and an almost full recovery at the end of the exposure period. Functional genomics by means of Gene Ontology term analysis unraveled typical mussel stress responses i.e. aminoglycan (chitin) metabolic processes but also more specific effects such as the regulation of NF-kappa B transcription factor activity. (C) 2016 Elsevier Ltd. All rights reserved

    Are QR codes here to stay or are they a thing of the past?

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    Quick response (QR) codes, a type of two-dimensional barcode, are a marketing tool used all around the world. Particularly, in Japan and China QR codes have been gaining popularity. Early adopters with higher education and recent promotional marketing campaigns are utilizing this mobile, information-sharing tool. QR codes are now widely used as a marketing tool by many companies. This research investigates consumers’ perception of QR codes. An increasing amount of firms and sales representatives are using QR codes as a channel to market their products/services to their customers’ mobile devices. The following questions will be the focus of this study: 1. What are the factors that impact consumers’ attitudes towards QR codes? 2. Does the location of the code have an effect on the attitude towards the QR code? 3. Do consumers have a more positive attitude towards QR codes when they are aware of the destination/ information that will be presented? 4. Does one gender have a more positive attitude towards QR codes over the other gender? 5. Does the availability of QR codes prevent or enhance a positive attitude towards QR codes? 6. Are consumers more likely to have a positive attitude towards QR if they know that they will be led to a coupon by scanning? The data was collected through exploratory/descriptive research to record what QR users think about the application and how useful it is to them. The study included a collection of secondary data from various sources as well as a pre-test that was distributed to 15-30 students. Then primary data was collected from an online survey created with appropriate measures

    Exploring Prosocial Behavior through Structured Philosophical Dialogue: A Quantitative Evaluation

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    The problem of bullying in schools cannot be overstated. Researchers have examined the problem of bullying in schools from a variety of perspectives and have found that bullying has serious short- and long-term effects not just for the victim but for the bully as well. A variety of interventions have been implemented, and research shows that the majority, which are monological in nature, have demonstrated minimal, if any, impact on counteracting occurrences of bullying in schools. This study uses three quantitative measures to examine the impact that an instructional method steeped in the dynamics of dialogical inquiry has on students’ attitudes and beliefs about aggression
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