112 research outputs found

    The Academic Effects of Chronic Exposure to Neighborhood Violence

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    We estimate the causal effect of repeated exposure to violent crime on test scores in New York City. We use two distinct empirical strategies; value-added models linking student performance on standardized exams to violent crimes on a student’s residential block, and a regression discontinuity approach that identifies the acute effect of an additional crime exposure within a one-week window. Exposure to violent crime reduces academic performance. Value added models suggest the average effect is very small; approximately -0.01 standard deviations in English Language Arts (ELA) and mathematics. RD models suggest a larger effect, particularly among children previously exposed. The marginal acute effect is as large as -0.04 standard deviations for students with two or more prior exposures. Among these, it is even larger for black students, almost a 10th of a standard deviation. We provide credible causal evidence that repeated exposure to neighborhood violence harms test scores, and this negative effect increases with exposure

    Charge separation technique for metal–oxide–silicon capacitors in the presence of hydrogen deactivated dopants

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    An improved charge separation technique for metal-oxide-silicon (MOS) capacitors is presented which accounts for the deactivation of substrate dopants by hydrogen at elevated irradiation temperatures or small irradiation biases. Using high-frequency capacitance-voltage (C-V) measurements, radiation-induced inversion voltage shifts are separated into components due to oxide trapped charge, interface traps and deactivated dopants, where the latter is computed from a reduction in Si capacitance. In the limit of no radiation-induced dopant deactivation, this approach reduces to the standard midgap charge separation technique used widely for the analysis of room-temperature irradiations. The technique is demonstrated on a p-type MOS capacitor irradiated with {sup 60}Co {gamma}-rays at 100 C and zero bias, where the dopant deactivation is significant

    Charge density wave ordering in NbSe3: possible models and the experimental evidence

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    Charge density wave (CDW) ordering in the prototypical low-dimensional compound NbSe3 is reconsidered. We show that the widely accepted CDW model with two incommensurate modulations, q1 = (0,0.241,0) and q2 = (0.5,0.260,0.5), localized on type-III and type-I bi-capped trigonal prismatic (BCTP) columns, does not explain some details, revealed by various microscopic methods. The suggested alternative explanation is in a better accord with the entire experimental evidence, including low-temperature (LT) scanning tunneling microscopy (STM) results. It is based on the existence of modulated layered nano-domains formed below both CDW onset temperatures. According to this model, two of the three slightly different BCTP types of columns are modulated by the same wave vector, either q1 or q2, which can easily switch over in a domain as a whole. This approach explains the presence of the q2 modulation in the STM images recorded above the T2 CDW transition and the absence of the q2 satellites in the corresponding diffraction patterns. The long periodic modulation, detected by LT STM is attributed to a beating between the two CDWs, centered on adjacent columns of the same type. These pairs of columns, both either of type-III or type-I, modulated by the two alternative CDWs, represent the basic modulation units, ordered into nano-domains

    Interprofessional Collaboration Led by Health Professional Students: A Case Study of the Inter Health Professional Alliance at Virginia Commonwealth University

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    Background: Internationally recognized health experts have identified the need for an interdisciplinary approach to meet the healthcare needs of the 21st century, but academic institutions have been slow to take action. In response, eight health professional students at Virginia Commonwealth University developed a student-led organization, the Inter Health Professionals Alliance (IHPA), to foster a collaborative, interdisciplinary environment among health professional students.Methods and Findings: The eight students utilized a participatory action research approach to identify 1) an understanding behind the motivation for developing IHPA and 2) the core benefits of group involvement. Four benefits were identified: the development of knowledge and skills, interprofessional networks, professional competence, and role clarity. The case study demonstrated that students can engage in interdisciplinary collaboration from a student-initiated approach and likely improve the care of future patients. Drawing on personal experiences, IHPA board members outline five pieces of wisdom to aid fellow students in the development of student-led interdisciplinary organizations.Conclusions: With enthusiasm and support, students can transform their educational experiences to meet the healthcare needs of the twenty-first century

    Decomposing teacher autonomy: A study investigating types of teacher autonomy and how current public school climate affects teacher autonomy

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    Teacher autonomy can lead to either exciting or vacuous learning experiences for students. Therefore, it is of critical import that school leaders understand the complexities associated with teacher autonomy. This dissertation examines how teachers view autonomy and whether or not the accountability associated with high stakes testing influences teachers\u27 perceptions of autonomy. Researchers have tended to view teacher autonomy as a unitary concept. This dissertation seeks to expand the knowledge base by decomposing autonomy and deepening our understanding of how high stakes accountability affects teachers\u27 perceptions of their own autonomy. First, a model is proposed in which autonomy is decomposed into six distinct sub-components: autonomy over curriculum, pedagogy, assessment, professional development, student discipline, and classroom environment. Second, the research examines the effects of external accountability on teacher autonomy by quantitatively and qualitatively comparing the perceptions of possessed and desired autonomy of teachers who are direct targets of external accountability to those same perceptions held by teachers who are not direct targets of external accountability. The results show that the six sub-component model of teacher autonomy provides a solid framework to understand the complex nature of teacher autonomy. The results further indicate that, both quantitatively and qualitatively, there are no fundamental differences in how the teachers who are differentially targets of external accountability perceive their levels of possessed or desired autonomy. Although external accountability may affect the amount of autonomy teachers perceive they have or desire, this effect is not dependent on the level of external accountability faced by teachers. The results also show that teachers generally desire more autonomy than they perceive they already possess. The results inform school leaders about the complex nature of teacher autonomy and how leaders can leverage the power of teacher autonomy to make schools better places for children to learn and grow

    Decomposing teacher autonomy: A study investigating types of teacher autonomy and how current public school climate affects teacher autonomy

    No full text
    Teacher autonomy can lead to either exciting or vacuous learning experiences for students. Therefore, it is of critical import that school leaders understand the complexities associated with teacher autonomy. This dissertation examines how teachers view autonomy and whether or not the accountability associated with high stakes testing influences teachers\u27 perceptions of autonomy. Researchers have tended to view teacher autonomy as a unitary concept. This dissertation seeks to expand the knowledge base by decomposing autonomy and deepening our understanding of how high stakes accountability affects teachers\u27 perceptions of their own autonomy. First, a model is proposed in which autonomy is decomposed into six distinct sub-components: autonomy over curriculum, pedagogy, assessment, professional development, student discipline, and classroom environment. Second, the research examines the effects of external accountability on teacher autonomy by quantitatively and qualitatively comparing the perceptions of possessed and desired autonomy of teachers who are direct targets of external accountability to those same perceptions held by teachers who are not direct targets of external accountability. The results show that the six sub-component model of teacher autonomy provides a solid framework to understand the complex nature of teacher autonomy. The results further indicate that, both quantitatively and qualitatively, there are no fundamental differences in how the teachers who are differentially targets of external accountability perceive their levels of possessed or desired autonomy. Although external accountability may affect the amount of autonomy teachers perceive they have or desire, this effect is not dependent on the level of external accountability faced by teachers. The results also show that teachers generally desire more autonomy than they perceive they already possess. The results inform school leaders about the complex nature of teacher autonomy and how leaders can leverage the power of teacher autonomy to make schools better places for children to learn and grow

    Conference Comments by the General Chair

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