Abstract.In the present work we use the NASA-JPL global ionospheric maps of total electron content (TEC), firstly to construct TEC maps (TEC vs. magnetic local time MLT, and magnetic latitude MLAT) in the interval from 1999 to 2005. These TEC maps were, in turn, used to estimate the annualto-mean amplitude ratio, A 1 , and the semiannual-to-mean amplitude ratio, A 2 , as well as the latitudinal symmetrical and asymmetrical parts, A and A of A 1 . Thus, we investigated in detail the TEC climatology from maps of these indices, with an emphasis on the quantitative presentation for local time and latitudinal changes in the seasonal, annual and semiannual anomalies of the ionospheric TEC. Then we took the TEC value at 14:00 LT to examine various anomalies at a global scale following the same procedure. Results reveal similar features appearing in NmF2, such as that the seasonal anomaly is more significant in the near-pole regions than in the far-pole regions and the reverse is true for the semiannual anomaly; the winter anomaly has least a chance to be observed at the South America and South Pacific areas. The most impressive feature is that the equinoctial asymmetry is most prominent at the East Asian and South Australian areas. Through the analysis of the TIMED GUVI columnar [O/N2] data, we have investigated to what extent the seasonal, annual and semiannual variations can be explained by their counterparts in [O/N2]. Results revealed that the [O/N2] variation is a major contributor to the daytime winter anomaly of TEC, and it also contributes to some of the semiannual and annual anomalies. The contribution to the anomalies unexplained by the [O/N2] data could possibly be due to the dynamics associated with thermospheric winds and electric fields.

We investigate vortex pinning in thin superconducting films with a square array of rectangular submicron holes ("antidots"). Two types of antidots are considered: antidots fully perforating the superconducting film, and "blind antidots", holes that perforate the film only up to a certain depth. In both systems, we observe a distinct anisotropy in the pinning properties, reflected in the critical current Ic, depending on the direction of the applied electrical current: parallel to the long side of the antidots or perpendicular to it. Although the mechanism responsible for the effect is very different in the two systems, they both show a higher critical current and a sharper IV-transition when the current is applied along the long side of the rectangular antidots.

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The Pt∕BaTiO3 (BTO) interface was investigated by angle-resolved x-ray photoelectron spectroscopy and x-ray reflectivity technique. It was shown that there exists a transition layer of about 9Å at the Pt/BTO interface with electron density lower than that of the BTO film. The transition layer shows a higher binding energy of Ba 3d than that of the bulk BTO. Moreover, neither the interdiffusion of BTO and Pt nor the oxidation of Pt near the interface had been observed. We consider that this layer is caused by “interface-induced relaxation.” This relaxation layer is believed to be the origin of the “dead layer” effect.

Identifying new indications for drugs plays an essential role at many phases of drug research and development. Computational methods are regarded as an effective way to associate drugs with new indications. However, most of them complete their tasks by constructing a variety of heterogeneous networks without considering the biological knowledge of drugs and diseases, which are believed to be useful for improving the accuracy of drug repositioning. To this end, a novel heterogeneous information network (HIN) based model, namely HINGRL, is proposed to precisely identify new indications for drugs based on graph representation learning techniques. More specifically, HINGRL first constructs a HIN by integrating drug–disease, drug–protein and protein–disease biological networks with the biological knowledge of drugs and diseases. Then, different representation strategies are applied to learn the features of nodes in the HIN from the topological and biological perspectives. Finally, HINGRL adopts a Random Forest classifier to predict unknown drug–disease associations based on the integrated features of drugs and diseases obtained in the previous step. Experimental results demonstrate that HINGRL achieves the best performance on two real datasets when compared with state-of-the-art models. Besides, our case studies indicate that the simultaneous consideration of network topology and biological knowledge of drugs and diseases allows HINGRL to precisely predict drug–disease associations from a more comprehensive perspective. The promising performance of HINGRL also reveals that the utilization of rich heterogeneous information provides an alternative view for HINGRL to identify novel drug–disease associations especially for new diseases.

The magnetization and electrical transport in the superlattices consisting of ferromagnetic La0.67Sr0.33MnO3 and nonmagnetic insulating SrTiO3 layers have been investigated. A significant displacement of the hysteresis loop along the field axis is observed when the sample is field-cooled through the blocking temperature TB. The strength of displacement, termed as exchange field HE, is found to exponentially decay with temperature. The magnetoresistance in field-cooling process is obviously enhanced compared to that in zero-field-cooling process. The existence of the disordered spin state at the interface is suggested to be the origin of such phenomena.

Electron-doped La 2−x Ce x CuO 4 (LCCO) thin films were successfully prepared on (100) SrTiO 3 substrates by the dc magnetron sputtering method. The optimal-doped films show a highly c-axis oriented single T -type structure, and the zero resistance temperature T C0 is 25 K. In the normal state, the nearly quadratic temperature dependence of the resistivity was found and attributed to the Landau-Fermi liquid behaviour due to electron-electron scattering. At the same time, the negative sign of the Hall coefficient for such films well above T C obviously confirms the electron-type nature. The optimal conditions for the growth of single-phase T -type LCCO thin films are also discussed in detail.