The role of unit evaluation, learning and culture dimensions related to student cognitive style in hypermedia learning

Recent developments in learning technologies such as hypermedia are\ud becoming widespread and offer significant contributions to improving the delivery\ud of learning and teaching materials. A key factor in the development of hypermedia\ud learning systems is cognitive style (CS) as it relates to users‟ information\ud processing habits, representing individual users‟ typical modes of perceiving,\ud thinking, remembering and problem solving.\ud \ud \ud \ud \ud A total of 97 students from Australian (45) and Malaysian (52) universities\ud participated in a survey. Five types of predictor variables were investigated with\ud the CS: (i) three learning dimensions; (ii) five culture dimensions; (iii) evaluation\ud of units; (iv) demographics of students; and (v) country in which students studied.\ud Both multiple regression models and tree-based regression were used to analyse\ud the direct effect of the five types of predictor variables, and the interactions within\ud each type of predictor variable. When comparing both models, tree-based\ud regression outperformed the generalized linear model in this study. The research\ud findings indicate that unit evaluation is the primary variable to determine students‟\ud CS. A secondary variable is learning dimension and, among the three dimensions,\ud only nonlinear learning and learner control dimensions have an effect on students‟\ud CS. The last variable is culture and, among the five culture dimensions, only\ud power distance, long term orientation, and individualism have effects on students‟\ud CS. Neither demographics nor country have an effect on students‟ CS.\ud These overall findings suggest that traditional unit evaluation, students‟\ud preference for learning dimensions (such as linear vs non-linear), level of learner\ud control and culture orientation must be taken into consideration in order to enrich\ud students‟ quality of education. This enrichment includes motivating students to\ud acquire subject matter through individualized instruction when designing,\ud developing and delivering educational resources

Tunneling magnetoresistance in Mn2_2Au-based pure antiferromagnetic tunnel junction

Antiferromagnetic (AF) spintronics is merit on ultra-high operator speed and stability in the presence of magnetic field. To fully use the merit, the device should be pure rather than hybrid with ferromagnet or ferrimagnet. For the magnetism in the antiferromagnet is canceled by that of different sublattices, breaking the symmetry in the material can revive the native magnetism, which can be detected by the magnetoresistance (MR) effect. Achieving noticeable MR effect in the pure AF device is diffcult but essential for the AF spintronic applications. Here, we study the tunnel magnetoresistance(TMR) effect in the Nb/Mn$_2$Au/CdO/Mn$_2$Au/Nb pure AF magnetic tunnel junctions (AF-MTJs) based on a first-principle scattering theory. Giant TMRs with order of 1000% are predicted in some symmetric junctions, which is originated from the interfacial resonance tunneling effect related with the k dependent complex band structures of CdO and Mn$_2$Au in companion with the enhanced spin polarization of the interfacial magnetic atoms. The effect of voltage bias and interfacial disorder such as Oxygen vacancy, Manganese vacancy, and Manganese-Cadmium exchanges at Mn2Au/CdO interfaces are studied also. Our studies suggest Nb/Mn$_2$Au/CdO/Mn$_2$Au/Nb AFMTJs promising material for AF spintronic application, and rocksalt CdO a potential symmetry filtering material for spintronic applications

Suppressing disease spreading by using information diffusion on multiplex networks

Although there is always an interplay between the dynamics of information diffusion and disease spreading, the empirical research on the systemic coevolution mechanisms connecting these two spreading dynamics is still lacking. Here we investigate the coevolution mechanisms and dynamics between information and disease spreading by utilizing real data and a proposed spreading model on multiplex network. Our empirical analysis finds asymmetrical interactions between the information and disease spreading dynamics. Our results obtained from both the theoretical framework and extensive stochastic numerical simulations suggest that an information outbreak can be triggered in a communication network by its own spreading dynamics or by a disease outbreak on a contact network, but that the disease threshold is not affected by information spreading. Our key finding is that there is an optimal information transmission rate that markedly suppresses the disease spreading. We find that the time evolution of the dynamics in the proposed model qualitatively agrees with the real-world spreading processes at the optimal information transmission rate.Comment: 11 pages, 8 figure

Anisotropic magneto-resistance in MgO-based magnetic tunnel junctions induced by spin-orbit coupling

We performed a first-principles study of the tunneling anisotropic magneto-resistance (TAMR) in Ag(Ir,Pt)$/$MgO$/$Fe junctions. Enhanced TAMR with ideal and skewed fourfold angular dependence is found in-plane and out-of-plane TAMR of the system, respectively, which shows simple barrier thickness dependency with number around 10\% in some junctions. The complex angular dependency of the interfacial resonant states due to the spin-orbit coupling should be responsible to the complex and enhanced TAMR found in these junctions.Comment: 6 pages, 8 figure

Relationship between serum albumin and pulse wave velocity in patients on continuous ambulatory peritoneal dialysis

Li-Tao Cheng1, Li-Jun Tang1,2, Hui-Min Chen1,3, Wen Tang1, Tao Wang11Division of Nephrology, Peking University Third Hospital, Beijing, China; 2Division of Nephrology, Qilu Hospital of Shandong University, Ji’nan, China; 3Division of Cardiology, Guangdong Provincial Hospital of Traditional Chinese Medicine, Guangzhou, ChinaBackground: Hypoalbuminemia is a risk factor for cardiovascular events and mortality in dialysis patients, but the underlying mechanism remains unclear. Meanwhile, increased pulse wave velocity (PWV), the marker of arterial stiffness, has been proved to be an independent predictor of cardiovascular disease. The relationship between serum albumin and PWV in continuous ambulatory peritoneal dialysis patients (CAPD) was studied.Methods: Sixty-two CAPD patients were studied. The average age was 63 ± 12 years and dialysis duration was 23 ± 22 months. Serum albumin, C-reactive protein (CRP), and carotid-femoral PWV were measured.Results: Among these patients, 43.5% were men. The mean serum albumin concentration was 37 ± 4 g/L and PWV was 11.9 ± 2.3 m/s. PWV positively correlated with age (r = 0.35, P < 0.01), diabetes (yes = 1, no = 0; r = 0.292, P < 0.05), systolic blood pressure (SBP; r = 0.493, P < 0.001) and CRP (r = 0.295, P < 0.05), but negatively correlated with serum albumin (r = −0.357, P < 0.01). In multiple regression analysis, SBP (β = 0.615, P < 0.001), age (β = 0.414, P < 0.01), albumin (β = −0.315, P < 0.05) and total cholesterol (β = 0.275, P < 0.05) were independent determinants of PWV. In a non-inflamed subgroup (CRP < 3 mg/L, n = 30), albumin still negatively correlated with PWV (r = −0.66, P < 0.001).Conclusion: Serum albumin inversely correlated with increased PWV in CAPD patients, suggesting that increased arterial stiffness might be the link between hypoalbuminemia and increased cardiovascular mortality in dialysis patients.Keywords: hypoalbuminemia, cardiovascular events, pulse wave velocity, arterial stiffness, peritoneal dialysi

N-[2-(2-Chloro­phen­yl)-2-hydroxy­ethyl]propan-2-aminium hemioxalate

The asymmetric unit of the title compound, C11H17ClNO+·0.5C2O4 2−, consists of one N-[2-(2-chloro­phen­yl)-2-hydroxy­ethyl]propan-2-ammonium cation and one-half of a centrosymmetric oxalate anion. In the cation, the C/C/N plane of the ethyl­ammonium group is almost perpendicular to the benzene ring, with a dihedral angle of 88.72 (17)°. In the crystal structure, the two components are connected by O—H⋯O and N—H⋯O hydrogen bonds, forming a supra­molecular tape along the a axis. Between the tapes, a C—H⋯O inter­action is observed

Dynamic Evolution of Eukaryotic Mitochondrial and Nuclear Genomes: A Case Study in the Gourmet Pine Mushroom Tricholoma matsutake

Fungi, as eukaryotic organisms, contain two genomes, the mitochondrial genome and the nuclear genome, in their cells. How the two genomes evolve and correlate to each other is debated. Herein, taking the gourmet pine mushroom Tricholoma matsutake as an example, we performed comparative mitogenomic analysis using samples collected from diverse locations and compared the evolution of the two genomes. The T. matsutake mitogenome encodes 49 genes and is rich of repetitive and non-coding DNAs. Six genes were invaded by up to 11 group I introns, with one cox1 intron cox1P372 showing presence/absence dynamics among different samples. Bioinformatic analyses suggested limited or no evidence of mitochondrial heteroplasmy. Interestingly, hundreds of mitochondrial DNA fragments were found in the nuclear genome, with several larger than 500 nt confirmed by PCR assays and read count comparisons, indicating clear evidence of transfer of mitochondrial DNA into the nuclear genome. Nuclear DNA of T. matsutake showed a higher mutation rate than mitochondrial DNA. Furthermore, we found evidence of incongruence between phylogenetic trees derived from mitogenome and nuclear DNA sequences. Together, our results reveal the dynamic genome evolution of the gourmet pine mushroom.Peer reviewe