Search

Severe fever with thrombocytopenia syndrome virus (SFTSV) is spreading rapidly in Asia. It is transmitted by Haemaphysalis longicornis (Asian longhorned tick, ALT), which has both parthenogenetically and sexually reproducing populations. Parthenogenetic populations were found in at least 15 provinces in China and strongly correlated with the distribution of SFTS. The distribution of SFTS cases was however poorly correlated with the distribution of populations of bisexual ALTs. Phylogeographic analysis suggested that the parthenogenetic population spread much faster than bisexual population because colonization is independent of sexual reproduction. A higher proportion of parthenogenetic ALTs were collected from migratory birds captured at an SFTS endemic area, implicating the contribution to the long-range movement of ALTs in China. The SFTSV susceptibility of parthenogenetic females was like that of bisexual females under laboratory conditions. These results suggest that parthenogenetic ALT, probably transported by migratory birds, play a major role in the rapid spread of SFTSV.Article Summary LineThe parthenogenetic population of Asian longhorned tick is broadly distributed in China and plays a major role in the long-distance spread of SFTSV and perhaps future invasion of countries outside of Asia.

Rare-earth iron garnet films with perpendicular magnetic anisotropy (PMA) are important to develop magnon-based spintronic devices. In this study, high quality epitaxial Ho3Fe5O12 (HoIG) films with PMA are fabricated on (111) Y3(Sc2Ga3)O12 substrates by sputtering. The magnetization compensation temperature of HoIG films is determined to be 130 K, highly consistent with its bulk value. The magnetic dead layer at the interface is quantified as thin as about 0.6 nm through polarized neutron reflectivity. Furthermore, spin–orbit torque switching in HoIG/Pt films is realized with the threshold current density of 1.4 × 1011 A/m2 and assisting field as small as 10 Oe. These results provide one more alternative for spintronic materials using compensated ferrimagnetic insulators.

In ferromagnet/heavy metal bilayers, a spin current can be generated under the ferromagnetic resonance (FMR) condition, and then converted into a charge current in adjacent nonmagnetic metals through inverse spin Hall effect (ISHE). Here, we report an experimental observation of interface induced ISHE enhancement in NiFe/Pt bilayers covered by MgO layer. Compared to bare NiFe/Pt bilayers, Pt/MgO interface induces an enhancement of the spin-charge conversion in the NiFe/Pt/MgO trilayers with very thin Pt layers, in agreement with the corresponding trend of Gilbert damping enhancement. When the thickness of Pt is below 1.6 nm, the ISHE induced charge current has about 70% enhancement. These results open a new pathway to improve the spin-charge conversion efficiency by interface engineering.

Nanometer-thick Y3Fe5O12 (YIG) films epitaxially grown on (111) Gd3Ga5O12 with a magnetic dead layer as thin as about 1.2 nm are quantified by polarized neutron reflectivity and magnetization measurements. Vacuum annealing on YIG at 300–400 °C leads to substantial reduction in the anomalous Hall effect, spin Hall magnetoresistance, and spin pumping in YIG/Pt bilayers but causes large enhancement in the spin Seebeck effect. The structural, static, and dynamic magnetic measurements show that the annealing has no discernible influence on the global oxidization states and saturation magnetization of YIG films but introduces subtle defects possibly in the form of oxygen vacancies. This study suggests that subtle defects in thin YIG films have multiple effects on the spin transport properties, and caution should be taken in annealing YIG in vacuum.

The main mechanism of the CHADS2and CHA2DS2-VASc scores to predict stroke in nonvalvular atrial fibrillation (NVAF) is still controversial. We evaluated the association of the CHADS2and CHA2DS2-VASc scores with left atrial thrombus (LAT) as detected by transesophageal echocardiographic (TEE) and compared the predictive ability of these risk stratification schemes with nonvalvular atrial fibrillation (NVAF). Data from 2,695 consecutive NVAF patients in whom TEE was performed for screening LAT from July 2007 to February 2014 were analyzed. Only 3% of the subjects had LAT. Presence of LAT was not significantly associated with either CHADS2 (P=0.07)or CHA2DS2-VASc score(P=0.12). The area under the curve (AUC) concerning LAT prediction using CHADS2and CHA2DS2-VASc was 0.574 and 0.569, respectively. A composition model includes previous stroke or transient ischemic attack, nonparoxysmal AF, moderate to severe left ventricular systolic dysfunction, left atrial enlargement, and cardiomyopathy which improved the discrimination significantly (AUC = 0.743). In our cohort, both CHADS2and CHA2DS2-VASc scores were of limited value for predicting LAT in patients with NVAF. This questions the CHADS2/CHA2DS2-VASc score predicting stroke mainly through the mechanism of cardiogenic embolism. A scoring scheme combining clinical and echocardiographic parameters may better predict LAT as a surrogate for cardioembolic risk in NVAF patients.

To assess New York Heart Association (NYHA) functional class, left ventricular ejection fraction (LVEF), N-terminal pro-B-type natriuretic peptide (NT-proBNP) in predicting left atrial (LA) thrombus detected by transesophageal echocardiographic in Chinese patients with nonvalvular atrial

Purpose: We tried to find out if inflammation was related to the thrombosis of left auricle in patients with persistent atrial fibrillation (AF). Methods: 158 Consecutive inward patients with persistent non-valvular AF undergoing catheter ablation (RFCA) during 2009 were enrolled. Transesophageal echocardiography (TEE), echocardiography and blood sample collecting for hsCRP and TNF-αtesting had been carried out. Patients were separated into thrombosis or control group according to the result of TEE. 10 patients with persistent AF and left atrial appendage thrombus undergoing cardiac surgery were enrolled too. Tissue of left and right atrial appendages was cut intraoperation for western blot, real time PCR (RT-PCR) and inmunohistochemistry (ICH) analysis of TNF-α. Result: 31 patients (21.3%) were found thrombus in left auricle while 3 (1.9%) in right auricle and 2 (1.3%) in both. Totally 36 patients were enrolled into study group. The Left atrial diameter (LAD) and right atrial diameter (RAD) were greater in the study group (46.42±6.05 vs. 39.68±5.77mm, P=0.000; 56.08±8.04 vs. 51.92±6.80mm, P=0.002). Serum concentration of hsCRP and TNF-αincreased in the study group too (4.80±2.23 vs. 2.36±1.03 (mg/L), P=0.000; 9.87±3.33 vs. 5.23±2.14 (ng/ml), P=0.000). Levels of hsCRP and TNF-α were positively correlate to LAD (r=0.618 and r=0.596 separately, P