Non-volatile phase-change memory devices utilize local heating to toggle between crystalline and amorphous states with distinct electrical properties. Expanding on this kind of switching to two topologically distinct phases requires controlled non-volatile switching between two crystalline phases with distinct symmetries. Here, we report the observation of reversible and non-volatile switching between two stable and closely related crystal structures, with remarkably distinct electronic structures, in the near-room-temperature van der Waals ferromagnet Fe5-δGeTe2. We show that the switching is enabled by the ordering and disordering of Fe site vacancies that results in distinct crystalline symmetries of the two phases, which can be controlled by a thermal annealing and quenching method. The two phases are distinguished by the presence of topological nodal lines due to the preserved global inversion symmetry in the site-disordered phase, flat bands resulting from quantum destructive interference on a bipartite lattice, and broken inversion symmetry in the site-ordered phase.
Digital mask projection lithography (DMPL) technology is gaining significant attention due to its characteristics of free-mask, flexibility, and low cost. However, when dealing with target layouts featuring sizes smaller than the wavelength scale, accurately producing resist patterns that closely match the target layout using conventional methods to design the modulation coefficients of digital masks produced by spatial light modulators (SLM) becomes challenging. Here, we present digital inversion lithography technology (DILT), which offers what we believe to be a novel approach to reverse engineer the modulation coefficients of digital masks. In the case of binary amplitude modulation, DILT achieves a remarkable reduction in pattern errors (PE), reaching the original 0.26. At the same time, in the case of the gray amplitude modulation, the PE can be reduced to the original 0.05, which greatly improves the high-fidelity transfer of the target layout. This significant improvement enhances the accuracy of target design transfer. By leveraging the capabilities of DILT, DMPL can now attain higher precision and reliability, paving the way for more advanced applications in the field of micro-nano device manufacturing.
The high content of aluminum (Al) impurity in the recycled cathode powder seriously affects the extraction efficiency of Nickel, Cobalt, Manganese, and Lithium resources and the actual commercial value of recycled materials, so Al removal is crucially important to conform to the industrial standard of spent Li-ion battery cathode materials. In this work, we systematically investigated the leaching process and optimum conditions associated with Al removal from the cathode powder materials collected in a wet cathode-powder peeling and recycling production line of spent Li-ion batteries (LIBs). Moreover, we specifically studied the leaching of fluorine (F) synergistically happened along with the removal process of Al, which was not concerned about in other studies, but one of the key factors affecting pollution prevention in the recovery process. The mechanism of the whole process including the leaching of Al and F from the cathode powder was indicated by using NMR, FTIR, and XPS, and a defluoridation process was preliminarily investigated in this study. The leaching kinetics of Al could be successfully described by the shrinking core model, controlled by the diffusion process and the activation energy was 11.14 kJ/mol. While, the leaching of F was attributed to the dissolution of LiPF6 and decomposition of PVDF, and the kinetics associated was described by Avrami model. The interaction of Al and F is advantageous to realize the defluoridation to some degree. It is expected that our investigation will provide theoretical support for the large-scale recycling of spent LIBs.
Aluminum , Lithium , Fluorine , Powders , Recycling , Electric Power Supplies , Electrodes , Ions
Existing studies have recognized the significance of leadership ability on enterprises' digital transformation. However, few of them pay attention to the mechanism of flexible leadership ability (FLA) on digital transformation willingness (DTW). This study aims to explore the influence mechanism of FLA on DTW based on the ability-behavior-purpose logical framework. Survey data is collected from 509 large and medium-sized manufacturing enterprises in China, and multiple regression and PROCESS Macro methods are used for hypothesis testing. This study mainly discusses the impact of FLA on DTW, as well as the mediating role of innovation commitment (IC) and the moderating role of environmental dynamics (ED). Results show that FLA promotes DTW directly (ß = 0.574, p<0.001) and indirectly, that is, through IC (the main effect decreased from (ß = 0.574, p<0.001) to (ß = 0.40, p<0.001). Additionally, the moderating role of ED affects the direct path of FLA on DTW (ß = 0.167, p<0.001) as well as the two indirect paths (ß = 0.196, p<0.001; ß = 0.104, p<0.01). The findings contribute to the advancement of flexible leadership theory, and provide practical advice for enterprises on how to implement digital transformation.
Commerce , Leadership , China , Research Design
We study the interplay between electronic correlations and hybridization in the low-energy electronic structure of CaMn[Formula: see text]Bi[Formula: see text], a candidate hybridization-gap semiconductor. By employing a DFT+U approach we find both the antiferromagnetic Néel order and band gap in good agreement with the corresponding experimental values. Under hydrostatic pressure, we find a crossover from hybridization gap to charge-transfer insulting physics due to the delicate balance of hybridization and correlations. Increasing the pressure above [Formula: see text] GPa we find a simultaneous pressure-induced volume collapse, plane-to-chain, insulator to metal transition. Finally, we have also analyzed the topology in the antiferromagnetic CaMn[Formula: see text]Bi[Formula: see text] for all pressures studied.
PURPOSE: Severe traumatic brain injury (TBI) leads to acute coma and may result in prolonged disorder of consciousness (pDOC). We aimed to determine whether right median nerve electrical stimulation is a safe and effective treatment for accelerating emergence from coma after TBI. METHODS: This randomised controlled trial was performed in 22 centres in China. Participants with acute coma at 7-14 days after TBI were randomly assigned (1:1) to either routine therapy and right median nerve electrical stimulation (RMNS group) or routine treatment (control group). The RMNS group received 20 mA, 300 µs, 40 Hz stimulation pulses, lasting 20 s per minutes, 8 h per day, for 2 weeks. The primary outcome was the proportion of patients who regained consciousness 6 months post-injury. The secondary endpoints were Glasgow Coma Scale (GCS), Full Outline of Unresponsiveness scale (FOUR), Coma Recovery Scale-Revised (CRS-R), Disability Rating Scale (DRS) and Glasgow Outcome Scale Extended (GOSE) scores reported as medians on day 28, 3 months and 6 months after injury, and GCS and FOUR scores on day 1 and day 7 during stimulation. Primary analyses were based on the intention-to-treat set. RESULTS: Between March 26, 2016, and October 18, 2020, 329 participants were recruited, of whom 167 were randomised to the RMNS group and 162 to the control group. At 6 months post-injury, a higher proportion of patients in the RMNS group regained consciousness compared with the control group (72.5%, n = 121, 95% confidence interval (CI) 65.2-78.7% vs. 56.8%, n = 92, 95% CI 49.1-64.2%, p = 0.004). GOSE at 3 months and 6 months (5 [interquartile range (IQR) 3-7] vs. 4 [IQR 2-6], p = 0.002; 6 [IQR 3-7] vs. 4 [IQR 2-7], p = 0.0005) and FOUR at 28 days (15 [IQR 13-16] vs. 13 [interquartile range (IQR) 11-16], p = 0.002) were significantly increased in the RMNS group compared with the control group. Trajectory analysis showed that significantly more patients in the RMNS group had faster GCS, CRS-R and DRS improvement (p = 0.01, 0.004 and 0.04, respectively). Adverse events were similar in both groups. No serious adverse events were associated with the stimulation device. CONCLUSION: Right median nerve electrical stimulation is a possible effective treatment for patients with acute traumatic coma, that will require validation in a confirmatory trial.
Brain Injuries, Traumatic , Coma, Post-Head Injury , Humans , Coma, Post-Head Injury/therapy , Coma/etiology , Coma/therapy , Median Nerve , Brain Injuries, Traumatic/complications , Brain Injuries, Traumatic/therapy , Glasgow Coma Scale , Electric Stimulation
Defect engineering of van der Waals semiconductors has been demonstrated as an effective approach to manipulate the structural and functional characteristics toward dynamic device controls, yet correlations between physical properties with defect evolution remain underexplored. Using proton irradiation, we observe an enhanced exciton-to-trion conversion of the atomically thin WS2. The altered excitonic states are closely correlated with nanopore induced atomic displacement, W nanoclusters, and zigzag edge terminations, verified by scanning transmission electron microscopy, photoluminescence, and Raman spectroscopy. Density functional theory calculation suggests that nanopores facilitate formation of in-gap states that act as sinks for free electrons to couple with excitons. The ion energy loss simulation predicts a dominating electron ionization effect upon proton irradiation, providing further evidence on band perturbations and nanopore formation without destroying the overall crystallinity. This study provides a route in tuning the excitonic properties of van der Waals semiconductors using an irradiation-based defect engineering approach.
Magnetic proximity interactions between atomically thin semiconductors and two-dimensional magnets provide a means to manipulate spin and valley degrees of freedom in non-magnetic monolayers, without using applied magnetic fields1-3. In such van der Waals heterostructures, magnetic proximity interactions originate in the nanometre-scale coupling between spin-dependent electronic wavefunctions in the two materials, and typically their overall effect is regarded as an effective magnetic field acting on the semiconductor monolayer4-8. Here we demonstrate that magnetic proximity interactions in van der Waals heterostructures can in fact be markedly asymmetric. Valley-resolved reflection spectroscopy of MoSe2/CrBr3 van der Waals structures reveals strikingly different energy shifts in the K and K' valleys of the MoSe2 due to ferromagnetism in the CrBr3 layer. Density functional calculations indicate that valley-asymmetric magnetic proximity interactions depend sensitively on the spin-dependent hybridization of overlapping bands and as such are likely a general feature of hybrid van der Waals structures. These studies suggest routes to control specific spin and valley states in monolayer semiconductors9,10.
In this paper, we present a novel approach for calculating the heat distribution within a processed workpiece subjected to laser irradiation while accounting for the influence of bottom water vapor. A comprehensive mathematical model is introduced and numerical techniques using difference approximation are employed. Initially, the three-dimensional heat equation, originally defined in the rectangular coordinate system, is transformed into a corresponding model within the cylindrical coordinate system, incorporating a nonlinear boundary condition to account for coupling effects. Subsequently, leveraging the axial symmetry of the heat distribution, the three-dimensional model is simplified into a two-dimensional one. This simplified model is solved using the alternating direction implicit scheme coupled with the Crank-Nicolson method. Moreover, we develop a high-precision numerical treatment for the nonlinear boundary condition within the cylindrical coordinate system. To validate our methodology, simulation experiments are conducted on three distinct samples. Our comparative results demonstrate the feasibility and efficiency of the proposed approach in the context of water-jet guided laser processing.
Neural network-based inverse lithography technology (NNILT) has been used to improve the computational efficiency of large-scale mask optimization for advanced photolithography. NNILT is now mostly based on labels, and its performance is affected by the quality of labels. It is difficult for NNILT to achieve high performance and extrapolation ability for mask optimization without using labels. Here, we propose a label-free NNILT (LF-NNILT), which is implemented completely without labels and greatly improves the printability of the target layouts and the manufacturability of the synthesized masks compared to the traditional ILT. More importantly, the optimization speed of LF-NNILT is two orders of magnitude faster than the traditional ILT. Furthermore, LF-NNILT is simpler to implement and can achieve better solvers to support the development of advanced lithography.
Neural Networks, Computer , Printing , Technology
Recent investigations indicate that ß2-adrenergic receptor (ß2-AR) signaling may facilitate the progression of various tumors, whose underlying mechanisms remain largely elusive. In the present study, we showed that ß2-AR recruited Cdc42 in response to isoproterenol (ISO, a ß-AR selective agonist) exposure in pancreatic ductal adenocarcinoma (PDAC) cells. The association of ß2-AR and Cdc42 promoted the activation of Cdc42, as revealed by increased levels of Cdc42-GTP, and co-incubation with ß2-AR antagonist abrogated ISO-induced activation of Cdc42. ß2-AR-mediated Cdc42 activation further led to the phosphorylation of downstream PAK1, LIMK1 and Merlin. Furthermore, we showed that the activation of ß2-AR/Cdc42 signaling facilitated the migration and invasion of PDAC cells. In addition, ß2-AR and Cdc42 were overexpressed in PDAC specimens, compared with adjacent non-tumor tissues. High expression of ß2-AR and Cdc42 were correlated with lymph node metastasis and TNM stage in PDAC patients. Finally, we showed that overexpression of ß2-AR and Cdc42 were indicative of unfavorable prognosis in PDAC patients. Taken together, our findings suggested that ß2-AR might facilitate Cdc42 signaling to drive the migration and invasion of PDAC cells, consequently resulting in the metastasis and dismal prognosis of PDAC. These studies highlight targeting ß2-AR/Cdc42 signaling as a therapeutic strategy against PDAC.
Carcinoma, Pancreatic Ductal , Pancreatic Neoplasms , Carcinoma, Pancreatic Ductal/genetics , Carcinoma, Pancreatic Ductal/metabolism , Carcinoma, Pancreatic Ductal/pathology , Cell Line, Tumor , Cell Movement , Cell Proliferation , Gene Expression Regulation, Neoplastic , Humans , Lim Kinases/metabolism , Pancreatic Neoplasms/genetics , Pancreatic Neoplasms/metabolism , Pancreatic Neoplasms/pathology , Receptors, Adrenergic, beta-2 , Signal Transduction , Pancreatic Neoplasms
BACKGROUND: To investigate the preventive effect of elastic stockings on deep vein thrombosis (DVT) after orthopedic surgery by literature search and meta-analysis. METHODS: PubMed, Embase and Cochrane were selected as the search database platforms to search the literature of randomized controlled trials related to elastic stockings and DVT published from 2008 to date. Revman 5.3.5 software was used for statistical analysis of the data to obtain forest and funnel plots. RESULTS: In this study, 90 studies were initially screened and 7 were finally included, covering a total of 3,116 patients. Meta-analysis showed that the 7 studies had statistical heterogeneity (I2=32%, P=0.18), so a random effect model was used. The obtained statistic was [odds ratio (OR) =0.59, 95% confidence interval (CI): (0.34, 1.03)], the statistical effect size was Z=1.84, P=0.07, and the difference was not statistically significant, so a stepwise sensitivity analysis was performed by the exclusion method. One study was excluded, and the remaining 6 showed homogeneity (I2=0%, P=0.46). They were analyzed by subgroup according to the type of operation: ankle surgery or hip and knee arthroplasty. The internal literatures of each subgroup were homogeneous: ankle surgery subgroup (I2=0%, P=0.43), hip and knee arthroplasty subgroup (I2=0%, P=0.88). Therefore, fixed effect mode analysis was used, and the effect size of elastic stockings after ankle surgery was Z=3.65, P=0.0003, while the effect size of elastic stockings in the hip and knee arthroplasty subgroup was Z=1.23, P=0.22. DISCUSSION: Elastic stockings had an obvious preventive effect on DVT in patients undergoing ankle surgery, but not in patients undergoing lumbar, knee or spinal surgery. It is necessary to combine anticoagulant drugs and other physical therapies to prevent DVT.
Orthopedic Procedures , Thrombosis , Venous Thrombosis , Humans , Orthopedic Procedures/adverse effects , Stockings, Compression , Venous Thrombosis/prevention & control
Recent advances in nanoscience have opened ways of recycling substrates for nanomaterial growth. Novel materials, such as atomically thin materials, are highly desirable for the recycling substrates. In this work, we report recycling of monolayer graphene as a growth template for synthesis of single crystalline ZnO nanowires. Selective nucleation of ZnO nanowires on graphene was elucidated by scanning electron microscopy and density functional theory calculation. Growth and subsequent separation of ZnO nanowires was repeated up to seven times on the same monolayer graphene film. Raman analyses were also performed to investigate the quality of graphene structure along the recycling processes. The chemical robustness of graphene enables the repetitive ZnO nanowire growth without noticeable degradation of the graphene quality. This work presents a route for graphene as a multifunctional growth template for diverse nanomaterials such as nanocrystals, aligned nanowires, other two-dimensional materials, and semiconductor thin films.
Previous studies have shown aberrant expression of ubiquitin-specific protease 14 (USP14) in multiple malignancies, suggesting an important role of USP14 in tumorigenesis. However, the functional role of USP14 in pancreatic ductal adenocarcinoma (PDAC) has never been elucidated. In this study, we found that USP14 was remarkably upregulated in PDAC tissues compared with normal pancreatic tissues. Notably, Kaplan-Meier curves showed that high expression of USP14 predicted significantly worse prognosis in PDAC patients than low expression of USP14. To determine whether USP14 could regulate the proliferation, apoptosis and metastasis of PDAC cells, we knocked down endogenous USP14 or overexpressed exogenous USP14 in Panc-1 and BxPC-3 cells. Using MTT assays, colony formation analyses, flow cytometry assays, and cell invasion and migration assays, we found that knockdown of USP14 attenuated proliferation, induced apoptosis and restrained invasion and migration of PDAC cells. Overexpression of USP14 could enhance proliferation, prevent apoptosis and promote invasion and migration of PDAC cells. In addition, USP14 could regulate the expression of cyclin D1, PCNA and E-cadherin, three important carcinogenic factors, in PDAC cells. These findings suggest that USP14 might play an important role in promoting the tumorigenesis of PDAC and thus be a promising therapeutic target to prevent PDAC progression.
Carcinoma, Pancreatic Ductal/enzymology , Carcinoma, Pancreatic Ductal/pathology , Pancreatic Neoplasms/enzymology , Pancreatic Neoplasms/pathology , Ubiquitin Thiolesterase/metabolism , Apoptosis/genetics , Apoptosis/physiology , Cell Line, Tumor , Cell Proliferation/genetics , Cell Proliferation/physiology , Cell Transformation, Neoplastic/genetics , Cell Transformation, Neoplastic/metabolism , Gene Expression Regulation, Neoplastic/genetics , Gene Expression Regulation, Neoplastic/physiology , Humans , In Vitro Techniques , Prognosis , Ubiquitin Thiolesterase/genetics , Pancreatic Neoplasms
Spin-triplet superconductors are of extensive current interest because they can host topological state and Majorana fermions important for quantum computation. The uranium-based heavy-fermion superconductor UTe_{2} has been argued as a spin-triplet superconductor similar to UGe_{2}, URhGe, and UCoGe, where the superconducting phase is near (or coexists with) a ferromagnetic (FM) instability and spin-triplet electron pairing is driven by FM spin fluctuations. Here we use neutron scattering to show that, although UTe_{2} exhibits no static magnetic order down to 0.3 K, its magnetism in the [0,K,L] plane is dominated by incommensurate spin fluctuations near an antiferromagnetic ordering wave vector and extends to at least 2.6 meV. We are able to understand the dominant incommensurate spin fluctuations of UTe_{2} in terms of its electronic structure calculated using a combined density-functional and dynamic mean-field theory.
BACKGROUND: Deep venous thrombosis (DVT) is a common postoperative complication in patients with lower limb fractures. This study aims to investigate the predictive value of plasminogen activator inhibitor-1 (PAI-1), fibrinogen (FIB), and D-dimer (D-D) for DVT following lower limb traumatic fracture surgery and to investigate risk factors for DVT. METHODS: Clinical data of 63 patients who underwent lower limb traumatic fracture surgery in our hospital from September 2018 to March 2019 were retrospectively analyzed. Patients were divided into a DVT group and a non-DVT group. The differences in the levels of plasminogen activator inhibitor-1 (PAI-1), fibrinogen (FIB), and D-dimer (D-D) were compared, and a receiver operating characteristic (ROC) curve was used to analyze their predictive value for DVT following surgery for lower limb traumatic fracture. Multiple logistic regression analysis was used to analyze the risk factors of DVT. RESULTS: The levels of PAI-1, FIB, and D-D in the DVT group were higher on the third day after surgery compared to the pre-surgical levels, and were also higher than those in the non-DVT group (P<0.05). The area under the ROC curve indicated that the predictive values of PAI-1, FIB, D-D, and the combination of these three indicators for DVT were 0.792, 0.429, 0.966, and 0.992, respectively. Patients with preexisting factors including a BMI ≥24 kg/m2 , a history of diabetes, postoperative infection, an abnormal white blood cell count, an abnormal average thrombocytocrit, and abnormal levels of PAI-1, FIB, and D-D had a higher incidence of DVT following surgery compared to patients without these factors (P<0.05). The results of the multivariate logistic regression model analysis showed that the presence of postoperative infection, abnormal white blood cell count, abnormal mean platelet volume, and abnormal levels of PAI-1, FIB, and D-D were independent risk factors affecting postoperative DVT in patients with lower limb fractures (P<0.05). CONCLUSIONS: The levels of PAI-1, FIB, and D-D were significantly increased in patients with DVT following surgery for lower limb fractures. Therefore, early monitoring of PAI-1, FIB, and D-D levels, and coagulation function is a good predictive indicator of postoperative thrombosis.
Fibrinogen , Venous Thrombosis , Fibrin Fibrinogen Degradation Products , Fibrinogen/analysis , Humans , Lower Extremity , Plasminogen Activator Inhibitor 1 , Retrospective Studies , Venous Thrombosis/etiology
The prediction of non-trivial topological electronic states in half-Heusler compounds makes these materials good candidates for discovering new physics and devices as half-Heusler phases harbour a variety of electronic ground states, including superconductivity, antiferromagnetism, and heavy-fermion behaviour. Here, we report a systematic studies of electronic properties of a superconducting half-Heusler compound YPtBi, in its normal state, investigated using angle-resolved photoemission spectroscopy. Our data reveal the presence of a Dirac state at the [Formula: see text] point of the Brillouin zone at 500 meV below the Fermi level. We observe the presence of multiple Fermi surface pockets, including two concentric hexagonal and six half-oval shaped pockets at the [Formula: see text] and K points of the Brillouin zone, respectively. Furthermore, our measurements show Rashba-split bands and multiple surface states crossing the Fermi level, this is also supported by the first-principles calculations. Our findings of a Dirac state in YPtBi contribute to the establishing of half-Heusler compounds as a potential platform for novel topological phases.
