2,769 research outputs found

    Does higher education foster critical and creative learners? An exploration of two universities in South Korea and the USA

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    This paper describes two studies that explore students' beliefs about critical and creative learning at two universities, and considers the implications of those beliefs in comparison to the universities' stated education goals. One is a mixed method study of students at a top university in Korea, and the second is a comparative study between the Korean university and a United States (US) university. The first study found that both high-achievers and the general population at a top Korean university perceived their critical and creative abilities as lower than their receptive learning abilities, and that higher achievers were neither more critical nor creative than lower achievers. The second study finds that the Korean university students, compared to US students, were more likely to rate their receptive learning ability as higher than their critical and creative learning abilities. Comparisons across year of higher education (HE) suggest that Korean students' perceptions did not significantly change with respect to year in school, while US students' perceptions of critical learning abilities significantly increased across school years. Results are discussed with respect to the impact of culture, epistemological beliefs, and HE instruction on critical and creative learning

    Relationship of functional gastrointestinal disorders and psychiatric disorders: Implications for treatment

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    This article revisits the links between psychopathology and functional gastrointestinal disorders such as irritable bowel syndrome (IBS), discusses the rational use of antidepressants as well as non-pharmacological approaches to the management of IBS, and suggests guidelines for the treatment of IBS based on an interdisciplinary perspective from the present state of knowledge. Relevant published literature on psychiatric disorders, especially somatization disorder, in the context of IBS, and literature providing direction for management is reviewed, and new directions are provided from findings in the literature. IBS is a heterogeneous syndrome with various potential mechanisms responsible for its clinical presentations. IBS is typically complicated with psychiatric issues, unexplained symptoms, and functional syndromes in other organ systems. Most IBS patients have multiple complaints without demonstrated cause, and that these symptoms can involve systems other than the intestine, e.g. bones and joints (fibromyalgia, temporomandibular joint syndrome), heart (non-cardiac chest pain), vascular (post-menopausal syndrome), and brain (anxiety, depression). Most IBS patients do not have psychiatric illness per se, but a range of psychoform (psychological complaints in the absence of psychiatric disorder) symptoms that accompany their somatoform (physical symptoms in the absence of medical disorder) complaints. It is not correct to label IBS patients as psychiatric patients (except those more difficult patients with true somatization disorder). One mode of treatment is unlikely to be universally effective or to resolve most symptoms. The techniques of psychotherapy or cognitive-behavioral therapy can allow IBS patients to cope more readily with their illness. Specific episodes of depressive or anxiety disorders can be managed as appropriate for those conditions. Medications designed to improve anxiety or depression are not uniformly useful for psychiatric complaints in IBS, because the psychoform symptoms that sound similar to those seen in psychiatric disorders may not have the same significance in patients with IBS

    Doping influence of spin dynamics and magnetoelectric effect in hexagonal Y0.7_{0.7}Lu0.3_{0.3}MnO3_{3}

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    We use inelastic neutron scattering to study spin waves and their correlation with the magnetoelectric effect in Y0.7_{0.7}Lu0.3_{0.3}MnO3_3. In the undoped YMnO3_3 and LuMnO3_3, the Mn trimerization distortion has been suggested to play a key role in determining the magnetic structure and the magnetoelectric effect. In Y0.7_{0.7}Lu0.3_{0.3}MnO3_3, we find a much smaller in-plane (hexagonal abab-plane) single ion anisotropy gap that coincides with a weaker in-plane dielectric anomaly at TNT_N. Since both the smaller in-plane anisotropy gap and the weaker in-plane dielectric anomaly are coupled to a weaker Mn trimerization distortion in Y0.7_{0.7}Lu0.3_{0.3}MnO3_3 comparing to YMnO3_3 and LuMnO3_3, we conclude that the Mn trimerization is responsible for the magnetoelectric effect and multiferroic phenomenon in Y1−y_{1-y}Luy_{y}MnO3_{3}.Comment: 5 pages, 5 figure

    Interplay Between Magnetic Frustration and Quantum Criticality in the Unconventional Ladder Antiferromagnet C9H18N2CuBr4

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    Quantum fluctuation in frustrated magnets and quantum criticality at the transition between different quantum phases of matter are two of the cornerstones in condensed matter physics. Here we demonstrate the nontrivial interplay between them in the spin-1/2 coupled two-leg ladder antiferromagnet C9H18N2CuBr4. Employing the high-resolution neutron spectroscopy, we unambiguously identify a weakly first-order hydrostatic pressure-driven quantum phase transition, which arises from fluctuations enhanced by the frustrating interlayer coupling. An exotic pressure-induced quantum disordered state is evidenced by the broad spectral linewidth observed near the phase transition. Interestingly, we find that the gapped transverse excitations in the Neel-ordered phase at ambient pressure cannot be described by the conventional S=1 magnons, i.e., the spin wave quanta, associated with explicit symmetry breaking, and thus the three-dimensional magnetic order ought to emerge in an unconventional way. We further apply the quantum Fisher information to show the presence of bipartite entanglement at criticality at least up to 1.1 K in the same material.Comment: 10 pages and 6 figures. We call for theoretical understanding of the nontrivial interplay observed in this materia

    Spam1-associated transmission ratio distortion in mice: Elucidating the mechanism

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    BACKGROUND: While transmission ratio distortion, TRD, (a deviation from Mendelian ratio) is extensive in humans and well-documented in mice, the underlying mechanisms are unknown. Our earlier studies on carriers of spontaneous mutations of mouse Sperm Adhesion Molecule 1 (Spam1) suggested that TRD results from biochemically different sperm, due to a lack of transcript sharing through the intercellular cytoplasmic bridges of spermatids. These bridges usually allow transcript sharing among genetically different spermatids which develop into biochemically and functionally equivalent sperm. OBJECTIVES: The goals of the study were to provide support for the lack of sharing (LOS) hypothesis, using transgene and null carriers of Spam1, and to determine the mechanism of Spam1-associated TRD. METHODS: Carriers of Spam1-Hyal5 BAC transgenes were mated with wild-type female mice and the progeny analyzed for TRD by PCR genotyping. Sperm from transgene and Spam1 null carriers were analyzed using flow cytometry and immunocytochemistry to detect quantities of Spam1 and/or Hyal5. Transgene-bearing sperm with Spam1 overexpression were detected by fluorescence in situ hybridization. In wild-type animals, EM studies of in situ transcript hybridization of testis sections and Northern analysis of biochemically fractionated testicular RNA were performed to localize Spam1 transcript. Finally, AU-rich motifs identified in the 3' UTR of Spam1 RNA were assayed by UV cross-linking to determine their ability to interact with testicular RNA binding proteins. RESULTS: The Tg8 line of transgene carriers had a significant (P < 0.001) TRD, due to reduced fertilizing ability of transgene-bearing sperm. These sperm retained large cytoplasmic droplets engorged with overexpressed Spam1 or Hyal5 protein. Caudal sperm from transgene carriers and caput sperm of null carriers showed a bimodal distribution of Spam1, indicating that the sperm in a male were biochemically different with respect to Spam1 quantities. Spam1 RNA was absent from the bridges, associated exclusively with the ER, and was shown to be anchored to the cytoskeleton. This compartmentalization of the transcript, mediated by cytoskeletal binding, occurs via protein interactions with 3' UTR AU-rich sequences that are likely involved in its stabilization. CONCLUSION: We provide strong support for the LOS hypothesis, and have elucidated the mechanism of Spam1-associated TRD

    BRYNTRN: A baryon transport model

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    The development of an interaction data base and a numerical solution to the transport of baryons through an arbitrary shield material based on a straight ahead approximation of the Boltzmann equation are described. The code is most accurate for continuous energy boundary values, but gives reasonable results for discrete spectra at the boundary using even a relatively coarse energy grid (30 points) and large spatial increments (1 cm in H2O). The resulting computer code is self-contained, efficient and ready to use. The code requires only a very small fraction of the computer resources required for Monte Carlo codes

    Evaluating options for sustainable energy mixes in South Korea using scenario analysis

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    a b s t r a c t To mitigate greenhouse gas emissions, coal-fired electricity infrastructure needs to be replaced by lowcarbon electricity generation options. Here we examine a range of possible alternative scenarios for sustainable electricity generation in South Korea, considering both physical and economic limits of current technologies. The results show that South Korea cannot achieve a 100% renewable energy mix and requires at least 55 GW of backup capacity. Given that constraint, we modelled seven scenarios: (i) the present condition, (ii) the First National Electricity Plan configuration, (iii) renewable energy (including 5 GW photovoltaic) with fuel cells or (iv) natural gas backup, (v) maximum renewable energy (including 75 GW photovoltaic) with natural gas, (vi) maximum nuclear power, and (vii) nuclear power with natural gas. We then quantify levelised cost of electricity, energy security, greenhouse gas emissions, fresh water consumption, heated water discharge, land transformation, air pollutant emissions, radioactive waste disposal, solid waste disposal and safety issues for each modelled mix. Our analysis shows that the maximum nuclear power scenario yields the fewest overall negative impacts, and the maximum renewable energy scenario with fuel cells would have the highest negative impacts
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