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High entropy oxides (HEOs), based on the incorporation of multiple-principal cations into the crystal lattice, offer the possibility to explore previously inaccessible oxide compositions and unconventional properties. Here it is demonstrated that despite the chemical complexity of HEOs external stimuli, such as epitaxial strain, can selectively stabilize certain magneto-electronic states. Epitaxial (Co0.2 Cr0.2 Fe0.2 Mn0.2 Ni0.2 )3 O4 -HEO thin films are grown in three different strain states: tensile, compressive, and relaxed. A unique coexistence of rocksalt and spinel-HEO phases, which are fully coherent with no detectable chemical segregation, is revealed by transmission electron microscopy. This dual-phase coexistence appears as a universal phenomenon in (Co0.2 Cr0.2 Fe0.2 Mn0.2 Ni0.2 )3 O4 epitaxial films. Prominent changes in the magnetic anisotropy and domain structure highlight the strain-induced bidirectional control of magnetic properties in HEOs. When the films are relaxed, their magnetization behavior is isotropic, similar to that of bulk materials. However, under tensile strain, the hardness of the out-of-plane (OOP) axis increases significantly. On the other hand, compressive straining results in an easy OOP magnetization and a maze-like magnetic domain structure, indicating the perpendicular magnetic anisotropy. Generally, this study emphasizes the adaptability of the high entropy design strategy, which, when combined with coherent strain engineering, opens additional prospects for fine-tuning properties in oxides.

Abstract: We investigated the distribution of HLA-DRB1 alleles in a sample of the Chinese Shantou population, and explored the relationship between HLA-DRB1 alleles and the susceptibility and clinical features of [...]

Perpendicular magnetic anisotropy (PMA) plays a critical role in spintronics, giving rise to improvements in fundamental research and industrial production. Generally, PMA originates mainly from the spin–orbit interaction with perpendicular orbital moment. However, electron orbitals are difficult to tune once they emerge. Here, we propose a simple and effective method for preparing (001)-oriented ultrathin La0.67Sr0.33MnO3 (LSMO) films with PMA, which is induced by compressive strain and surface symmetry breaking. Moreover, PMA was effectively strengthened by means of annealing under applied magnetic field. X-ray linear dichroism spectra reveal that PMA should be attributed to the preferential occupancy of the 3z2 − r2 orbital in LSMO films. The results presented here show that PMA can be manipulated by orbital reconstruction in perovskite manganite films under compressive strain through a simple and effective strategy. These findings illustrate a new method for designing and controlling magnetic anisotropy and might advance fundamental applications of orbital physics and spintronics. [ABSTRACT FROM AUTHOR]

Background: Osteoporosis is a common complication in patients with rheumatoid arthritis (RA). The change of bone mineral density (BMD) in patients with RA is slow, and little data are known about the long-term change of BMD., Objectives: This study aimed to determine the frequency of osteoporosis and the long-term change on BMD in a cohort of Chinese patients with RA routinely receiving calcium and vitamin D supplementation., Methods: A total of 304 consecutive patients with RA were recruited. Bone mineral density measurements of the forearm, lumbar spine, and total hip were performed by dual-energy x-ray absorptiometry and compared with 200 age- and sex-matched healthy controls. Risk factors were analyzed by logistic regression models., Results: The prevalence of osteoporosis at all measured sites in patients with RA was statistically significantly higher than in healthy controls. A total of 107 patients of the cohort had a mean of 4 years of follow-up. More patients with BMD decrease were found without calcium and vitamin D use compared with those who continuously took calcium and vitamin D (64.3% vs 19.8% at the forearm and 28.6% vs 16.1% at the total hip, respectively). Only the use of calcium and vitamin D supplementation was associated with a decreased risk of BMD decrease both at the forearm and at the total hip., Conclusions: Osteoporosis is common in Chinese patients with RA. Routine use of calcium and vitamin D supplementation decreased the risk of BMD decrease and should be recommended for all patients with RA.

Objective: To evaluate the prevalence of primary gout in the Shantou area, China, and to understand its clinical features., Methods: Samples from three surveys of the Chenghai across ten years were studied. Clinical, laboratory and radiology data of 419 cases of primary gout were collected and analyzed., Results: Prevalence of primary gout in the three surveys were 0.17%, 0.15% and 0.26%, respectively. Among the clinical patients, the ratio of male to female was 21:1; the average age of onset of women was significantly higher than that of men. The number of cases in the last ten years has been increasing. In the first wave of cases, the first metatarsophalangeal joint was involved in 82.1% of all cases; no fourth metatarsophalangeal joint involvement had been observed. Hyperlipemia was the most common accompanying abnormal laboratory test (57.1%). Radiographic bone erosion was found in 49.4% patients, most of them with disease duration more than 5 years., Conclusions: The prevalence of primary gout in Shantou area has been increasing in the last ten years. Changes in diet and lifestyle may be responsible for this rapid increase.