3,648 research outputs found
Lattice-coupled Antiferromagnet on Frustrated Lattices
Lattice-coupled antiferromagnetic spin model is analyzed for a number of
frustrated lattices: triangular, Kagome, and pyrochlore. In triangular and
Kagome lattices where ground state spins are locally ordered, the spin-lattice
interaction does not lead to a static deformation of the lattice. In the
pyrochlore structure, spin-lattice coupling supports a picture of the hexagon
spin cluster proposed in the recent experiment[S. H. Lee et al. Nature, 418,
856 (2002)]. Through spin-lattice interaction a uniform contraction of the
individual hexagons in the pyrochlore lattice can take place and reduce the
exchange energy. Residual hexagon-hexagon interaction takes the form of a
3-states Potts model where the preferred directions of the spin-loop directors
for nearby hexagons are mutually orthogonal
RHOA in Gastric Cancer: Functional Roles and Therapeutic Potential
The well-known signal mediator and small GTPase family member, RHOA, has now been associated with the progression of specific malignancies. In this review, we appraise the biomedical literature regarding the role of this enzyme in gastric cancer (GC) signaling, suggesting potential clinical significance. To that end, we examined RHOA activity, with regard to second-generation hallmarks of cancer, finding particular association with the hallmark “activation of invasion and metastasis.” Moreover, an abundance of studies show RHOA association with Lauren classification diffuse subtype, in addition to poorly differentiated GC. With regard to therapeutic value, we found RHOA signaling to influence the activity of specific widely used chemotherapeutics, and its possible antagonism by various dietary constituents. We also review currently available targeted therapies for GC. The latter, however, showed a paucity of such agents, underscoring the urgent need for further investigation into treatments for this highly lethal malignancy
Potassium-doped BaFe2As2 superconducting thin films with a transition temperature of 40 K
We report the growth of potassium-doped BaFe2As2 thin films, where the major
charge carriers are holes, on Al2O3 (0001) and LaAlO3 (001) substrates by using
an ex-situ pulsed laser deposition technique. The measured Tc's are 40 and 39 K
for the films grown on Al2O3 and LaAlO3, respectively and diamagnetism
indicates that the films have good bulk superconducting properties below 36 and
30 K, respectively. The X-ray diffraction patterns for both films indicated a
preferred c-axis orientation, regardless of the substrate structures of LaAlO3
and Al2O3. The upper critical field at zero temperature was estimated to be
about 155 T.Comment: 6 pages including 3 figure
In-situ fabrication of cobalt-doped SrFe2As2 thin films by using pulsed laser deposition with excimer laser
The remarkably high superconducting transition temperature and upper critical
field of iron(Fe)-based layered superconductors, despite ferromagnetic material
base, open the prospect for superconducting electronics. However, success in
superconducting electronics has been limited because of difficulties in
fabricating high-quality thin films. We report the growth of high-quality
c-axis-oriented cobalt(Co)-doped SrFe2As2 thin films with bulk
superconductivity by using an in-situ pulsed laser deposition technique with a
248-nm-wavelength KrF excimer laser and an arsenic(As)-rich phase target. The
temperature and field dependences of the magnetization showing strong
diamagnetism and transport critical current density with superior Jc-H
performance are reported. These results provide necessary information for
practical applications of Fe-based superconductors.Comment: 8 pages, 3figures. to be published at Appl. Phys. Let
Network Analysis of TV-Viewing Patterns in Multi-Channel Circumstances
Translated from the article published in Korean Journal of Broadcasting vol. 24, no. 6, 2010, with permission from the Korean Association for Broadcasting and Telecommunication Studies.This study uses the network analysis method to overcome limitations of previous research that had inaccurately examined the phenomena of fragmentation and polarization in TV viewing behaviors. First of all, viewer ratings were analyzed, which consisted of 298 panels in 2004 and 2007. The benefit of this panel data was not only to secure the validity and credibility of the data, but also to figure out the change of viewing patterns. The result of network centralization and centrality analysis was that fragmentation became stronger as the number of channels increased. In other words, audiences dispersed to professional and specialized channels. However, they came together from terrestrial broadcastings to other channels again. The re-concentration phenomenon appeared apparently in drama channels that belonged to terrestrial (non-satellite or cable) broadcastings. In addition, sub-network analysis showed that small but loyal viewer groups kept on increasing. This result indicates the depth of polarization, which means audiences have a tendency to view common genre programs according to their preference
The Influence of Tibial Positioning on the Diagnostic Accuracy of Combined Posterior Cruciate Ligament and Posterolateral Rotatory Instability of the Knee
Background: To determine if tibial positioning affects the external rotation of the tibia in a dial test for posterolateral rotatory instability combined with posterior cruciate ligament (PCL) injuries. Methods: Between April 2007 and October 2007, 16 patients with a PCL tear and posterolateral rotatory instability were diagnosed using a dial test. The thigh-foot angle was measured at both 30 ° and 90 ° of knee fl exion with an external rotation stress applied to the tibia in 2 different positions (reduction and posterior subluxation). The measurements were performed twice by 2 orthopedic surgeons. Results: In posterior subluxation, the mean side-to-side difference in the thigh-foot angle was 11.56 ± 3.01 ° at 30 ° of knee fl exion and 11.88 ± 4.03 ° at 90 ° of knee flexion. In the sequential dial test performed with the tibia reduced, the mean side-to-side difference was 15.94 ± 4.17 ° (p < 0.05) at 30 ° of knee fl exion and 16.88 ± 4.42 ° (p = 0.001) at 90 ° of knee fl exion. The mean tibial external rotation was 5.31 ± 2.86 ° and 6.87 ± 3.59 ° higher in the reduced position than in the posterior subluxation at both 30° and 90 ° of knee fl exion. Conclusions: In the dial test, reducing the tibia with an anterior force increases the ability of an examiner to detect posterolateral rotary instability of the knee combined with PCL injuries
Thermoelectric properties of graphene incorporated thermoelectric materials
Thermoelectric materials, which can change the waste heat into the usable electricity, are interested in various field of applications such as vehicle, ship, power plane, and so on. To enhance the thermoelectric properties, high electrical conductivity, high Seebeck coefficient, and low thermal conductivity should be conducted, however, the trade-off relation between electronic property and thermal property in terms of carrier concentration could be the bottle-neck on the enhancement of thermoelectric properties of the materials. In this presentation, we discuss with the graphene incorporation in the conventional thermoelectric materials, which could lead to independently control electric and thermal properties
Quantitative agreement of Dzyaloshinskii-Moriya interactions for domain-wall motion and spin-wave propagation
The magnetic exchange interaction is the one of the key factors governing the
basic characteristics of magnetic systems. Unlike the symmetric nature of the
Heisenberg exchange interaction, the interfacial Dzyaloshinskii-Moriya
interaction (DMI) generates an antisymmetric exchange interaction which offers
challenging opportunities in spintronics with intriguing antisymmetric
phenomena. The role of the DMI, however, is still being debated, largely
because distinct strengths of DMI have been measured for different magnetic
objects, particularly chiral magnetic domain walls (DWs) and non-reciprocal
spin waves (SWs). In this paper, we show that, after careful data analysis,
both the DWs and SWs experience the same strength of DMI. This was confirmed by
spin-torque efficiency measurement for the DWs, and Brillouin light scattering
measurement for the SWs. This observation, therefore, indicates the unique role
of the DMI on the magnetic DW and SW dynamics and also guarantees the
compatibility of several DMI-measurement schemes recently proposed.Comment: 24 pages, 5 figure
Electrochemical-mechanical phase field model for electroplating process
Please click Additional Files below to see the full abstrac
- …