The manipulation of topological states in quantum matter is an essential pursuit of fundamental physics and next-generation quantum technology. Here we report the magnetic manipulation of Weyl ...fermions in the kagome spin-orbit semimetal Co_{3}Sn_{2}S_{2}, observed by high-resolution photoemission spectroscopy. We demonstrate the exchange collapse of spin-orbit-gapped ferromagnetic Weyl loops into paramagnetic Dirac loops under suppression of the magnetic order. We further observe that topological Fermi arcs disappear in the paramagnetic phase, suggesting the annihilation of exchange-split Weyl points. Our findings indicate that magnetic exchange collapse naturally drives Weyl fermion annihilation, opening new opportunities for engineering topology under correlated order parameters.
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Demyelination is a common pathological finding in human neurological diseases and frequently persists as a result of failure of endogenous repair. Transplanted oligodendrocytes and their precursor ...cells can (re)myelinate axons, raising the possibility of therapeutic intervention. The migratory capacity of transplanted cells is of key importance in determining the extent of (re)myelination and can, at present, be evaluated only by using invasive and irreversible procedures. We have exploited the transferrin receptor as an efficient intracellular delivery device for magnetic nanoparticles, and transplanted tagged oligodendrocyte progenitor cells into the spinal cord of myelin-deficient rats. Cell migration could be easily detected by using three-dimensional magnetic resonance microscopy, with a close correlation between the areas of contrast enhancement and the achieved extent of myelination. The present results demonstrate that magnetic resonance tracking of transplanted oligodendrocyte progenitors is feasible; this technique has the potential to be easily extended to other neurotransplantation studies involving different precursor cell types.
Long non-coding RNA was dismissed as merely transcriptional "noise" in the past decades. Numerous researches have shown that lncRNAs regulated gene expression at the epigenetic level. Moreover, ...lncRNAs played important roles in proliferation, apoptosis and invasiveness of tumor cells, and participated in metastatic capacity of cancers. Recent studies revealed HOX transcript antisense RNA, a lncRNA with regulatory functions of transcription, could bind PRC2 and LSD1/CoREST/REST complexes and direct to the specific gene sites, resulted in H3K27 methylation and H3K4 demethylation and ultimately gene silencing. Aberrant HOTAIR expression was associated with various sites of cancers such as breast, hepatocellular, gastric, colorectal, pancreatic et al; and affected survival and prognosis of cancer patients. In this review, we introduce an overall view of HOTAIR by describing the known molecular mechanisms and potential functions of HOTAIR and summarizing the latest progresses on the research of HOTAIR in various human cancers.
Maternal obesity is associated with an increased risk of developing gestational diabetes mellitus and it also results in an increased risk of giving birth to a large baby with increased fat mass. ...Furthermore, it is also contributes to an increased risk of obesity and insulin resistance in the offspring in childhood, adolescence and adult life. It has been proposed that exposure to maternal obesity may therefore result in an 'intergenerational cycle' of obesity and insulin resistance. There is significant interest in whether exposure to maternal obesity around the time of conception alone contributes directly to poor metabolic outcomes in the offspring and whether dieting in the obese mother before pregnancy or around the time of conception has metabolic benefits for the offspring. This review focusses on experimental and clinical studies that have investigated the specific impact of exposure to maternal obesity during the periconceptional period alone or extending beyond conception on adipogenesis, lipogenesis and on insulin signalling pathways in the fat, liver and muscle of the offspring. Findings from these studies highlight the need for a better evidence base for the development of dietary interventions in obese women before pregnancy and around the time of conception to maximize the metabolic benefits and minimize the metabolic costs for the next generation.
Magnetic multilayers offer diverse opportunities for the development of ultrafast functional devices through advanced interface and layer engineering. Nevertheless, a method for determining their ...dynamic properties as a function of depth throughout such stacks has remained elusive. By probing the ferromagnetic resonance modes with element-selective soft x-ray resonant reflectivity, we gain access to the magnetization dynamics as a function of depth. Most notably, using reflectometry ferromagnetic resonance, we find a phase lag between the coupled ferromagnetic layers in CoFeB/MgO/Ta4 multilayers that is invisible to other techniques. The use of reflectometry ferromagnetic resonance enables the time-resolved and depth-resolved probing of the complex magnetization dynamics of a wide range of functional magnetic heterostructures with absorption edges in the soft x-ray wavelength regime.
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A Geographic Information System (GIS)-based quantitative risk assessment methodology was adopted to evaluate the risks of loose deposits formed by the 2008 Wenchuan earthquake along a highway near ...the epicenter. A total of 305 loose deposits with a total volume of 4.0 × 107 m3 has been identified. A physical model was used to determine the failure probability of these loose deposits under six rainfall scenarios, assuming the loose deposits as infinite slopes. The calculated probability of rain-induced slope failures is verified by the recorded landslides at the same site during a storm in 2010. Seventy-nine out of the 112 rain-induced loose deposit failures are predicted by the reliability analysis, with an accuracy of 71%. The results of reliability analysis and information on the consequence of these rain-induced landslides enable the estimation of the annual societal and individual risks of the loose deposits. Under the rainfall scenarios of 30 mm/12 h and 70 mm/12 h, the estimated annual societal risks reach 8.8 and 7.5, respectively, and the individual risks reach 0.05 and 0.04, respectively, which are very high compared with present risk acceptance criteria. The preliminary assessment provides a benchmark for studying the long-term risks of these loose deposits and engineering decision.
A modified variable step-size affine projection sign algorithm (MVSS-APSA) is proposed. Considering the effect of the noise on the steady-state error, the first moment estimation of the noise is ...utilised to modify the variable step-size update. The test on system identifications under an impulsive noise environment shows that the proposed MVSS-APSA has lower steady-state misalignment than the VSS-APSA.
•The amorphous nature and the thermostability of the Ti33Zr30Cu9Ni5.5Be22.5 BMG were almost unaffected by the DCT.•The DCT30 specimen exhibited a more prominent rejuvenation behavior manifested by a ...higher relaxation enthalpy.•The room-temperature plasticity of DCT30 specimen increased from 1.4% of the as-cast state to 7.8%.•The DCT30 specimen obtained the lowest average stress drop (15.9 MPa) and shear band formation energy (342.8 J/m2).•The DCT30 specimen possesses the larger volume and size of STZs.
This study investigates the effect of deep cryogenic cycle treatment (DCT) on the microstructure and mechanical behaviors of Ti33Zr30Cu9Ni5.5Be22.5 bulk metallic glass (BMG). The results revealed that after the DCT, the relaxation enthalpy increased, whereas the Ti33Zr30Cu9Ni5.5Be22.5 BMG still maintained a complete amorphous nature. As the cycle numbers increased, the room-temperature plasticity of the Ti33Zr30Cu9Ni5.5Be22.5 BMG represented a tendency to increase first and then decrease. When the cycle numbers increased to 30, the Ti33Zr30Cu9Ni5.5Be22.5 BMG obtained the maximum compressive plasticity of 7.8%, which is 5.6 times that of the as-cast specimen, accompanied by a higher strength. Moreover, the nanoindentation results demonstrated that the Ti33Zr30Cu9Ni5.5Be22.5 BMG that underwent the DCT possessed a larger pop-in size, a lower initial pop-in force and a lower hardness. The shear transformation zone (STZ) theory was employed to elucidate the plasticising mechanism induced by the DCT for the Ti33Zr30Cu9Ni5.5Be22.5 BMG. The larger STZ volumes and the lower shear band formation energy induced through the DCT promoted the densification of multiple shear bands, which is the principal reason for the excellent plasticity after the DCT.
To develop and validate a radiomics nomogram for identifying high-risk carotid plaques on computed tomography (CT) angiography (CTA).
A total of 280 patients with symptomatic (n=131) and asymptomatic ...(n=139) carotid plaques were divided into a training set (n=135), validation set (n=58), and external test set (n=87). Radiomic features were extracted from CTA images. A radiomics model was constructed based on selected features and a radiomics score (rad-score) was calculated. A clinical factor model was constructed by demographics and CT findings. A radiomics nomogram combining independent clinical factors and the rad-score was constructed. The diagnostic performance of three models was evaluated and validated by region of characteristic curves.
Calcification and maximum plaque thickness were the independent clinical factors. Twenty-four features were used to build the radiomics signature. In the validation set, the nomogram (area under the curve AUC, 0.977; 95% CI, 0.899–0.999) performed better (p=0.017 and p=0.031) than the clinical factor model (AUC, 0.862; 95% CI, 0.746–0.938) and radiomics signature (AUC, 0.944; 95% CI, 0.850–0.987). In external test set, the nomogram (AUC, 0.952; 95% CI, 0.884–0.987) and radiomics signature (AUC, 0.932; 95% CI, 0.857–0.975) showed better discrimination capability (p=0.002 and p=0.037) than clinical factor model (AUC, 0.818; 95% CI, 0.721–0.892).
The CT-based nomogram showed satisfactory performance in identification of high-risk plaques in carotid arteries, and it may serve as a potential non-invasive tool to identify carotid plaque vulnerability and risk stratification.
•Identifying symptomatic carotid plaque is difficult by conventional image modality.•A radiomics nomogram helps identify symptomatic plaque with improved efficacy.•The nomogram may be a potential tool to identify carotid vulnerable plaque.
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