617 research outputs found

    The Effects of Tablets on Learning: Does Studying from a Tablet Computer Affect Student Learning Differently Across Educational Levels

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    In recent years, students and educators alike have utilized new technologies such as tablet computers as a means of enhancing the learning process. While prior research suggests that these implementations within the classroom provide a new and beneficial method of relaying and learning information, scientists have begun to explore the possible side effects that these technologies have on the learning process. Although much of the current literature suggests that learning from an electronic screen does not affect efficacy compared to learning from printed text (Bayliss et al., 2012; Dundar & Akcayir, 2012), researchers continue to explore the possible consequences that using said technologies may have in academia. The current study aims to address how tablet computers affect the process of learning differently across levels of education. It is proposed that older generations, such as college students, who did not grow up with tablets in the classroom may suffer from the effects of proactive interference when compared to younger students who have been exposed to technologies much more profoundly in their education (e.g. elementary students). If this is so, the current study also proposes a possible intervention that would help students at any educational level overcome this interference in order to integrate tablets into their studies effectively

    Spin-stripe density varies linearly with hole content in single-layer Bi2201 cuprate

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    We have performed inelastic neutron scattering measurements on the single-layer cuprate Bi2+xSr2-xCuO6+y (Bi2201) with x=0.2, 0.3, 0.4 and 0.5, a doping range that spans the spin-glass (SG) to superconducting (SC) phase boundary. The doping evolution of low energy spin fluctuations was found to be characterized by a change of incommensurate modulation wave vector from the tetragonal [110] to [100]/[010] directions, while maintaining a linear relation between the incommensurability and the hole concentration, delta p. In the SC regime, the spectral weight is strongly suppressed below 4 meV. Similarities and differences in the spin correlations between Bi2201 and the prototypical single-layer system La2-xSrxCuO4 are discussed.Comment: 5 page,4 figure

    Ultrasonic attenuation in magnetic fields for superconducting states with line nodes in Sr2RuO4

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    We calculate the ultrasonic attenuation in magnetic fields for superconducting states with line nodes vertical or horizontal relative to the RuO_2 planes. This theory, which is valid for fields near Hc2 and not too low temperatures, takes into account the effects of supercurrent flow and Andreev scattering by the Abrikosov vortex lattice. For rotating in-plane field H(theta) the attenuation alpha(theta)exhibits variations of fourfold symmetry in the rotation angle theta. In the case of vertical nodes, the transverse T100 sound mode yields the weakest(linear)H and T dependence of alpha, while the longitudinal L100 mode yields a stronger (quadratic) H and T dependence. This is in strong contrast to the case of horizontal line nodes where alpha is the same for the T100 and L100 modes (apart from a shift of pi/4 in field direction) and is roughly a quadratic function of H and T. Thus we conclude that measurements of alpha in in-plane magnetic fields for different in-plane sound modes may be an important tool for probing the nodal structure of the gap in Sr_2RuO_4.Comment: 5 pages, 6 figures, replaced in non-preprint form, to appear in Phys. Rev.

    Abnormal direction of internal auditory canal and vestibulocochlear nerve

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    Several internal auditory canal (IAC) anomalies have been reported.To our knowledge, only one case with anabnormal direction of the IAC has been reported in an infant with Pierre Robin syndrome. In this paper, wepresent the first report of two non-syndromic cases with abnormal IAC direction.</p

    Single-crystal growth and dependences on the hole concentration and magnetic field of the magnetic ground state in the edge-sharing CuO2_2 chain system Ca2+x_{2+x}Y2x_{2-x}Cu5_5O10_{10}

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    We have succeeded in growing large-size single-crystals of Ca2+x_{2+x}Y2x_{2-x}Cu5_5O10_{10} with 0x1.670 \le x \le 1.67 and measured the magnetic susceptibility, specific heat and magnetization curve, in order to study the magnetic ground state in the edge-sharing CuO2_2 chain as a function of hole concentration and magnetic field. In 0x1.30 \le x \le 1.3, it has been found that an antiferromagnetically ordered phase with the magnetic easy axis along the b-axis is stabilized and that a spin-flop transition occurs by the application of magnetic fields parallel to the b-axis. The antiferromagnetic transition temperature decreases with increasing xx and disappears around x=x = 1.4. Alternatively, a spin-glass phase appears around x=1.5x = 1.5. At x=1.67x = 1.67 where the hole concentration is \sim 1/3 per Cu, it appears that a spin-gap state is formed owing to the formation of spin-singlet pairs. No sign of the coexistence of an antiferromagnetically ordered state and a spin-gap one suggested in Ca1x_{1-x}CuO2_2 has been found in Ca2+x_{2+x}Y2x_{2-x}Cu5_5O10_{10}.Comment: 13 pages, 12 figures, 1 tabl

    Low temperature electronic properties of Sr_2RuO_4 III: Magnetic fields

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    Based on the microscopic model introduced previously the observed specific heat and ac-susceptibility data in the superconducting phase in Sr_2RuO_4 with applied magnetic fields are described consistently within a phenomenological approach. Discussed in detail are the temperature dependence of the upper critical fields H_{c2} and H_2, the dependence of the upper critical fields on the field direction, the linear specific heat below the superconducting phase transition as a function of field or temperature, the anisotropy of the two spatial components of the order parameter, and the fluctuation field H_p.Comment: 8 pages REVTEX, 4 figure

    Mechanism of spin-triplet superconductivity in Sr2RuO4

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    The unique Fermi surfaces and their nesting properties of Sr2RuO4 are considered. The existence of unconventional superconductivity is shown microscopically, for the first time, from the magnetic interactions (due to nesting) and the phonon-mediated interactions. The odd-parity superconductivity is favored in the α\alpha and β\beta sheets of the Fermi surface, and the various superconductivities are possible in the γ\gamma sheet. There are a number of possible odd-parity gaps, which include the gaps with nodes, the breaking of time-reversal symmetry and dz^\vec{d}\parallel \hat{z}.Comment: 4 pages, 3 figure

    Single-crystal growth of underdoped Bi-2223

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    To investigate the origin of the enhanced Tc ({\approx} 110 K) of the trilayer cuprate superconductor Bi2Sr2Ca2Cu3O10+{\delta} (Bi-2223), its underdoped single crystals are a critical requirement. Here, we demonstrate the first successful in-plane resistivity measurements of heavily underdoped Bi-2223 (zero-resistivity temperatures {\approx} 20~35 K). Detailed crystal growth methods, the annealing process, as well as X-ray diffraction (XRD) and magnetic susceptibility measurement results are also reported.Comment: 4 pages, 4 figures, 27th International Symposium on Superconductivity, ISS 2014, to appear in Physics Procedi

    Disorder Effect on the Vortex Pinning by the Cooling Process Control in the Organic Superconductor κ\kappa-(BEDT-TTF)2_2Cu[N(CN)2_2]Br

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    We investigate the influence of disorders in terminal ethylene groups of BEDT-TTF molecules (ethylene-disorders) on the vortex pinning of the organic superconductor κ\kappa-(BEDT-TTF)2_2Cu[N(CN)2_2]Br. Magnetization measurements are performed under different cooling-processes. The second peak in the magnetization hysteresis curve is observed for all samples studied, and the hysteresis width of the magnetization becomes narrower by cooling faster. In contradiction to the simple pinning effect of disorder, this result shows the suppression of the vortex pinning force by introducing more ethylene-disorders. The ethylene-disorder domain model is proposed for explaining the observed result. In the case of the system containing a moderate number of the ethylene-disorders, the disordered molecules form a domain structure and it works as an effective pinning site. On the contrary, an excess number of the ethylene-disorders may weaken the effect of the domain structure, which results in the less effective pinning force on the vortices.Comment: 6 pages, 6 figure
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