3,428 research outputs found

    Structural-Symbolic Translation Fluency: Reliability, Validity, and Usability

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    Standardized formative mathematics assessments typically fail to capture the depth of current standards and curricula. Consequently, these assessments demonstrate limited utility for informing the instructional implementation choices of teachers. This problem is particularly salient as it relates to the mathematical problem solving process. The purpose of this study was to develop and evaluate the psychometric characteristics of Structural-Symbolic Translation Fluency, a curriculum-based measure (CBM) of mathematical problem solving. The development of the assessment was based on previous research describing the cognitive process of translation (Mayer, 2002) as well as mathematical concept development at the quantitative, structural, and symbolic levels (Dehaene, 2011; Faulkner, 2009; Griffin, 2004). Data on the Structural-Symbolic Translation Fluency assessment were collected from 11 mathematics and psychometrics experts and 42 second grade students during the spring of 2016. Data were analyzed through descriptive statistics, frequencies, Spearman-Brown correlation, joint probability of agreement, Pearson correlation, and hierarchical multiple regression. Psychometric features of interest included internal consistency, inter-rater reliability, test-retest reliability, content validity, and criterion-related validity. Testing of the 9 research questions revealed 9 significant findings. Despite significant statistical findings, several coefficients did not meet pre-established criteria required for validation. Hypothesized modifications to improve the psychometric characteristics are suggested as the focus of future research. In addition, recommendations are made concerning the role of assessing the translation process of mathematical problem solving

    Actions Speak Louder Than Words: When Should Courts Find that Institutions have a Duty to Protect Minor Children from Sexual Abuse?

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    This Comment focuses on the legal duty of institutions as it pertains to the sexual molestation and assault of children involved in youth programs by third parties working for the institution. This Comment analyzes the law of negligence, specifically the duty arising from a special relationship and other policy considerations, and uses it to simplify and enunciate a test which should be used to determine when a duty exists

    Drug development: Lessons from nature.

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    Natural products have been acknowledged for numerous years as a vital source of active ingredients in therapeutic agents. In particular, the use of active ingredients derived from plants for use in microbial natural products have long been used before the dawn of modern medicine. From ancient times, the efficacy of natural products has been associated with the chemistry, biochemistry and synthetic activities of natural products. Thus, with scientific advancement in modern molecular and cellular biology, analytical chemistry and pharmacology, the unique properties of these natural products are being harnessed in order to exploit the chemical and structural diversity and biodiversity of these types of products in relation to their therapeutic effect. Often, new molecules of interest in drug design units focus on the rearrangement of chemical entities or structural isomers of naturally occurring products in order to generate new molecules; these may be formulated into clinically useful therapies

    Calibration of the HAWC Gamma-Ray Observatory

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    The High-Altitude Water Cherenkov (HAWC) Experiment is a gamma-ray observatory that utilizes water silos as Cherenkov detectors to measure the electromagnetic air showers created by gamma rays. The experiment consists of an array of closely packed water Cherenkov detectors (WCDs), each with four photomultiplier tubes (PMTs). The direction of the gamma ray will be reconstructed using the times when the electromagnetic shower front triggers PMTs in each WCD. To achieve an angular resolution as low as 0.1 degrees, a laser calibration system will be used to measure relative PMT response times. The system will direct 300ps laser pulses into two fiber-optic networks. Each network will use optical fan-outs and switches to direct light to specific WCDs. The first network is used to measure the light transit time out to each pair of detectors, and the second network sends light to each detector, calibrating the response times of the four PMTs within each detector. As the relative PMT response times are dependent on the number of photons in the light pulse, neutral density filters will be used to control the light intensity across five orders of magnitude. This system will run both continuously in a low-rate mode, and in a high-rate mode with many intensity levels. In this thesis, the design of the calibration system and systematic studies verifying its performance are presented

    The use of nanotechnology in cardiovascular disease

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    Cardiovascular diseases claim a number of lives globally; many of which are preventable. With the increase in diets that consist of high saturated fat, salt, and sugar, people often living sedentary lifestyles, and a rise in cases of obesity, the incidence of cardiovascular disease is increasing. These contributing factors, coupled with more advanced methods of diagnosis, have delivered statistics that clearly show that there is a rising trend in the prevalence of cardiovascular disease. Treatment for cardiovascular diseases is limited currently to oral medicines or invasive surgery. There is a huge gap in this area of medicine for novel therapeutics for improved patient outcomes. Nanotechnology may provide a solution to more effective treatment of disease, with better prognoses and a reduced side effect profile. This review will explore for potential solutions to the limited pharmacological therapies currently on the market and the future that lies ahead for the place of nanotechnology within cardiovascular medicine

    Quantum electrodynamics of chiral waveguide arrays

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    We consider the quantum electrodynamics of a binary array of chiral waveguides, each containing many atoms. We show that the one-photon amplitude of a single-excitation state obeys a two-dimensional Dirac equation. Using this result, we develop the scattering theory for the Dirac equation in this setting and illustrate our results with numerical simulations

    On the importance of testing gravity at distances less than 1cm

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    If the mechanism responsible for the smallness of the vacuum energy is consistent with local quantum field theory, general arguments suggest the existence of at least one unobserved scalar particle with Compton wavelength bounded from below by one tenth of a millimeter. We show that this bound is saturated if vacuum energy is a substantial component of the energy density of the universe. Therefore, the success of cosmological models with a significant vacuum energy component suggests the existence of new macroscopic forces with range in the sub-millimeter region. There are virtually no experimental constraints on the existence of quanta with this range of interaction.Comment: 9 pages TeX, 2 eps figures, uses mtexsis.tex and epsf.tex. Entry in 1996 Gravity Research Foundation essay competition. To be published in the Journal of General Relativity and Gravitatio
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