276 research outputs found

    Indicators of Constructivist Principles in Internet-Based Courses

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    The purpose of this study was to provide greater assurance of quality in Internet-based courses. Current literature supports the assumption that the inclusion of constructivist principles in online courses adds to course quality. Therefore, identifying indicators of constructivist learning theory is important to the development of online courses. A peer-nominated panel of national experts in constructivism and instructional technology participated in a 3-round Delphi web survey. Through the iterative process, panelists assigned a mean rating of importance of 4.0 or higher (on a 5-point Likert scale) to 40 indicators of constructivist principles in online courses. Three implications for course design were identified; (1) one size (of learning model) does not fit all, (2) the six identified categories and their related indicators provide a framework for course development, and (3) indicators of constructivist principles transcend technology

    Indicators of Constructivist Principles in Internet-Based Courses

    Get PDF
    The purpose of this study was to provide greater assurance of quality in Internet-based courses. Current literature supports the assumption that the inclusion of constructivist principles in online courses adds to course quality. Therefore, identifying indicators of constructivist learning theory is important to the development of online courses. A peer-nominated panel of national experts in constructivism and instructional technology participated in a 3-round Delphi web survey. Through the iterative process, panelists assigned a mean rating of importance of 4.0 or higher (on a 5-point Likert scale) to 40 indicators of constructivist principles in online courses. Three implications for course design were identified; (1) one size (of learning model) does not fit all, (2) the six identified categories and their related indicators provide a framework for course development, and (3) indicators of constructivist principles transcend technology

    Observation of high-order quantum resonances in the kicked rotor

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    Quantum resonances in the kicked rotor are characterized by a dramatically increased energy absorption rate, in stark contrast to the momentum localization generally observed. These resonances occur when the scaled Planck's constant hbar=(r/s)*4pi, for any integers r and s. However only the hbar=r*2pi resonances are easily observable. We have observed high-order quantum resonances (s>2) utilizing a sample of low temperature, non-condensed atoms and a pulsed optical standing wave. Resonances are observed for hbar=(r/16)*4pi r=2-6. Quantum numerical simulations suggest that our observation of high-order resonances indicates a larger coherence length than expected from an initially thermal atomic sample

    A preliminary analysis of the data from experiment 77-13 and final report on glass fining experiments in zero gravity

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    Thermal fining, thermal migration of bubbles under reduced gravity conditions, and data to verify current theoretical models of bubble location and temperatures as a function of time are discussed. A sample, sodium borate glass, was tested during 5 to 6 minutes of zero gravity during rocket flight. The test cell contained a heater strip; thermocouples were in the sample. At present quantitative data are insufficient to confirm results of theoretical calculations

    An Electromyographic Study of Lower Trapezius Muscle Activity during the Traditional Muscle Testing Position and a Modified Position

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    Many people use repeated overhead movements in their occupations or recreational activities. Literature has shown that this repeated overhead activity greatly contributes to the incidence of shoulder pathologies such as impingement syndrome. The purpose of this study was to establish whether the lower trapezius was more successfully recruited in the traditional muscle testing position of 145° of shoulder abduction or a modified position consisting of shoulder external rotation while in 80° of shoulder abduction and 90° of elbow flexion. Forty-one subjects between the ages of 21 and 45 voluntarily participated in this study. One subject was excluded due to exceeding the 18- to 45-year-old age limit. EMG data were recorded and collected from the right lower trapezius of each subject while they completed 10 repetitions of each exercise in the traditional position with weight, the traditional position without weight, the modified position with weight, and the modified position without weight. The exercises were performed in a random order for each subject. Results of this study showed a significant difference in total and average lower trapezius muscle activity between the traditional position without weight and the traditional and modified positions with weight. The traditional and modified positions with weight demonstrated a greater level of EMG activity than the traditional position without weight. No significant difference was shown for total or average lower trapezius muscle activity between the traditional position without weight and the modified position without weight or between the traditional position with weight and the modified position with weight. The results indicated that exercise in the modified position with weight effectively recruits the lower trapezius at a higher amount than traditional positions and allows the patient to exercise the lower trapezius muscle in a position that is potentially less detrimental to the shoulder complex

    Phase Space Tomography of Classical and Nonclassical Vibrational States of Atoms in an Optical Lattice

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    Atoms trapped in optical lattice have long been a system of interest in the AMO community, and in recent years much study has been devoted to both short- and long-range coherence in this system, as well as to its possible applications to quantum information processing. Here we demonstrate for the first time complete determination of the quantum phase space distributions for an ensemble of 85Rb^{85}Rb atoms in such a lattice, including a negative Wigner function for atoms in an inverted state.Comment: Submitted to Journal of Optics B: Quantum and Semiclassical Optics. Special issue in connection with the 9th International Conference on Squeezed States and Uncertainty Relations, to be held in Besancon, France, on 2-6 May 200

    A Small Molecule that Induces Intrinsic Pathway Apoptosis with Unparalleled Speed

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    Apoptosis is generally believed to be a process thatrequires several hours, in contrast to non-programmed forms of cell death that can occur in minutes. Our findings challenge the time-consuming nature of apoptosis as we describe the discovery and characterization of a small molecule, named Raptinal, which initiates intrinsic pathway caspase-dependent apoptosis within minutes in multiple cell lines. Comparison to a mechanistically diverse panel of apoptotic stimuli reveals that Raptinal-induced apoptosis proceeds with unparalleled speed. The rapid phenotype enabled identification of the criticalroles of mitochondrial voltage-dependent anion channel function, mitochondrial membrane potential/coupled respiration, and mitochondrial complex I, III, and IV function for apoptosis induction. Use of Raptinal in whole organisms demonstrates its utility for studying apoptosis invivo for a variety of applications. Overall, rapid inducers of apoptosis are powerful tools that will be used in a variety of settings to generate further insight into the apoptotic machinery. Palchaudhuri etal. describe the discovery of a small molecule called "Raptinal" that induces unusually rapid apoptotic cell death via the intrinsic pathway. Their work describes the utility of Raptinal as a tool for apoptosis induction relative to other available small molecules

    A Homozygous Mutation in the Tight-Junction Protein JAM3 Causes Hemorrhagic Destruction of the Brain, Subependymal Calcification, and Congenital Cataracts

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    The tight junction, or zonula occludens, is a specialized cell-cell junction that regulates epithelial and endothelial permeability, and it is an essential component of the blood-brain barrier in the cerebrovascular endothelium. In addition to functioning as a diffusion barrier, tight junctions are also involved in signal transduction. In this study, we identified a homozygous mutation in the tight-junction protein gene JAM3 in a large consanguineous family from the United Arab Emirates. Some members of this family had a rare autosomal-recessive syndrome characterized by severe hemorrhagic destruction of the brain, subependymal calcification, and congenital cataracts. Their clinical presentation overlaps with some reported cases of pseudo-TORCH syndrome as well as with cases involving mutations in occludin, another component of the tight-junction complex. However, massive intracranial hemorrhage distinguishes these patients from others. Homozygosity mapping identified the disease locus in this family on chromosome 11q25 with a maximum multipoint LOD score of 6.15. Sequence analysis of genes in the candidate interval uncovered a mutation in the canonical splice-donor site of intron 5 of JAM3. RT-PCR analysis of a patient lymphoblast cell line confirmed abnormal splicing, leading to a frameshift mutation with early termination. JAM3 is known to be present in vascular endothelium, although its roles in cerebral vasculature have not been implicated. Our results suggest that JAM3 is essential for maintaining the integrity of the cerebrovascular endothelium as well as for normal lens development in humans

    SLC25A22 is a novel gene for migrating partial seizures in infancy

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    Objective To identify a genetic cause for migrating partial seizures in infancy (MPSI). Methods We characterized a consanguineous pedigree with MPSI and obtained DNA from affected and unaffected family members. We analyzed single nucleotide polymorphism 500K data to identify regions with evidence of linkage. We performed whole exome sequencing and analyzed homozygous variants in regions of linkage to identify a candidate gene and performed functional studies of the candidate gene SLC25A22. Results In a consanguineous pedigree with 2 individuals with MPSI, we identified 2 regions of linkage, chromosome 4p16.1-p16.3 and chromosome 11p15.4-pter. Using whole exome sequencing, we identified 8 novel homozygous variants in genes in these regions. Only 1 variant, SLC25A22 c.G328C, results in a change of a highly conserved amino acid (p.G110R) and was not present in control samples. SLC25A22 encodes a glutamate transporter with strong expression in the developing brain. We show that the specific G110R mutation, located in a transmembrane domain of the protein, disrupts mitochondrial glutamate transport. Interpretation We have shown that MPSI can be inherited and have identified a novel homozygous mutation in SLC25A22 in the affected individuals. Our data strongly suggest that SLC25A22 is responsible for MPSI, a severe condition with few known etiologies. We have demonstrated that a combination of linkage analysis and whole exome sequencing can be used for disease gene discovery. Finally, as SLC25A22 had been implicated in the distinct syndrome of neonatal epilepsy with suppression bursts on electroencephalogram, we have expanded the phenotypic spectrum associated with SLC25A22. Ann Neurol 2013;74:873-882 © 2013 American Neurological Association
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