Topological crystalline antiferromagnetic state in tetragonal FeS

Integration between magnetism and topology is an exotic phenomenon in condensed-matter physics. Here, we propose an exotic phase named topological crystalline antiferromagnetic state, in which antiferromagnetism intrinsically integrates with nontrivial topology, and we suggest such a state can be realized in tetragonal FeS. A combination of first-principles calculations and symmetry analyses shows that the topological crystalline antiferromagnetic state arises from band reconstruction induced by pair checker-board antiferromagnetic order together with band-gap opening induced by intrinsic spin-orbit coupling in tetragonal FeS. The topological crystalline antiferromagnetic state is protected by the product of fractional translation symmetry, mirror symmetry, and time-reversal symmetry, and present some unique features. In contrast to strong topological insulators, the topological robustness is surface-dependent. These findings indicate that non-trivial topological states could emerge in pure antiferromagnetic materials, which sheds new light on potential applications of topological properties in fast-developing antiferromagnetic spintronics.Comment: 8 pages, 6 figure

Molecular Lines of 13 Galactic Infrared Bubble Regions

We investigated the physical properties of molecular clouds and star formation processes around infrared bubbles which are essentially expanding HII regions. We performed observations of 13 galactic infrared bubble fields containing 18 bubbles. Five molecular lines, 12CO (J=1-0), 13CO (J=1-0), C18O(J=1-0), HCN (J=1-0), and HCO+ (J=1-0), were observed, and several publicly available surveys, GLIMPSE, MIPSGAL, ATLASGAL, BGPS, VGPS, MAGPIS, and NVSS, were used for comparison. We find that these bubbles are generally connected with molecular clouds, most of which are giant. Several bubble regions display velocity gradients and broad shifted profiles, which could be due to the expansion of bubbles. The masses of molecular clouds within bubbles range from 100 to 19,000 solar mass, and their dynamic ages are about 0.3-3.7 Myr, which takes into account the internal turbulence pressure of surrounding molecular clouds. Clumps are found in the vicinity of all 18 bubbles, and molecular clouds near four of these bubbles with larger angular sizes show shell-like morphologies, indicating that either collect-and-collapse or radiation-driven implosion processes may have occurred. Due to the contamination of adjacent molecular clouds, only six bubble regions are appropriate to search for outflows, and we find that four of them have outflow activities. Three bubbles display ultra-compact HII regions at their borders, and one of them is probably responsible for its outflow. In total, only six bubbles show star formation activities in the vicinity, and we suggest that star formation processes might have been triggered.Comment: 55 Pages, 32 figures. Accepted for publication in A

Evidence-based nursing in the application of mild and moderate hypertension research

目的  观察循证护理在轻、中度高血压患者中的应用效果，为护理干预模式提供依据。方法  将100例轻、中度高血压患者按照随机数字表分为循证组（50例），常规组（50例）。循证组从降低危险因素，形成健康生活行为循证，得到最佳证据给予临床护理。比较两组临床总有效率，健康行为。结果  循证护理组在提高临床疗效，形成健康的生活方式方面优于常规护理组（P<0.05）。结论  循证护理模式能够有效提高轻、中度高血压患者的临床疗效，减少疾病危险因素，养成健康的生活方式。Objective: To observe the effect of application of evidence-based nursing in patients with mild to moderate hypertension, and to provide basis for nursing intervention model. Methods: 100 patients with mild to moderate essential hypertension, were randomly divided into evidence-based group (50 cases), control group (50 cases). Evidence-based group gets the best evidence for clinical nursing from reducing risk factors, health behavior formation. Compared clinical total effective rate, health behavior between the two groups Results: the evidence-based nursing group is better than the routine nursing group (P<0.05) in improving the clinical curative effect, a healthy lifestyle. Conclusion: the evidence-based nursing mode can effectively improve the clinical efficacy in patients with mild to moderate hypertension, reduce disease, risk factors, and develop a healthy lifestyle