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Abstract Background Hematopoietic stem and progenitor cells (HSPCs) mobilize from bone marrow to peripheral blood in response to stress. The impact of alloresponse-induced stress on HSPCs mobilization in human liver transplantation (LTx) recipients remains under-investigated. Methods Peripheral blood mononuclear cell (PBMC) samples were longitudinally collected from pre- to post-LTx for one year from 36 recipients with acute rejection (AR), 74 recipients without rejection (NR), and 5 recipients with graft-versus-host disease (GVHD). 28 PBMC samples from age-matched healthy donors were collected as healthy control (HC). Multi-color flow cytometry (MCFC) was used to immunophenotype HSPCs and their subpopulations. Donor recipient-distinguishable major histocompatibility complex (MHC) antibodies determined cell origin. Results Before LTx, patients who developed AR after transplant contained more HSPCs in PBMC samples than HC, while the NR group patients contained fewer HSPCs than HC. After LTx, the HSPC ratio in the AR group sharply decreased and became less than HC within six months, and dropped to a comparable NR level afterward. During the one-year follow-up period, myeloid progenitors (MPs) biased differentiation was observed in all LTx recipients who were under tacrolimus-based immunosuppressive treatment. During both AR and GVHD episodes, the recipient-derived and donor-derived HSPCs mobilized into the recipient’s blood-circulation and migrated to the target tissue, respectively. The HSPCs percentage in blood reduced after the disease was cured. Conclusions A preoperative high HSPC ratio in blood characterizes recipients who developed AR after LTx. Recipients exhibited a decline in blood-circulating HSPCs after transplant, the cells mobilized into the blood and migrated to target tissue during alloresponse.

Hepatocellular carcinoma (HCC), a type of liver cancer, ranks as the sixth most prevalent cancer globally and represents the third leading cause of cancer-related deaths. Approximately half of HCC patients miss the opportunity for curative treatment and are then limited to undergoing systemic therapies. Currently, systemic therapy has entered the era of immunotherapy, particularly with the advent of immune-checkpoint inhibitors (ICIs), which have significantly enhanced outcomes for patients with advanced HCC. Neoadjuvant treatment for HCC has become a possibility—findings from the IMbrave 050 trial indicated that ICIs offer the benefit of recurrence-free survival for high-risk HCC patients post-resection or local ablation. However, only a small fraction of individuals benefit from systemic therapy. Consequently, there is an urgent need to identify predictive biomarkers for treatment response and outcome assessment. This study reviewed the historical progression of systemic therapy for HCC, highlighting notable therapeutic advancements. This study examined the development of systemic therapies involving conventional drugs and clinical trials utilized in HCC treatment, as well as potential predictive biomarkers for advanced and/or locally advanced HCC. Various studies have revealed potential biomarkers in the context of HCC treatment. These include the association of dendritic cells (DCs) with a favorable response to neoadjuvant therapy, the presence of enriched T effector cells and tertiary lymphoid structures, the identification of CD138+ plasma cells, and distinct spatial arrangements of B cells in close proximity to T cells among responders with locally advanced HCC receiving neoadjuvant cabozantinib and nivolumab treatment. Furthermore, pathological response has been associated with intratumoral cellular triads consisting of progenitor CD8+ T cells and CXCL13+ CD4+ T helper cells surrounding mature DCs in patients receiving neoadjuvant cemiplimab for resectable HCC. Despite no widely recognized predictive biomarkers for HCC individualized treatment, we believe neoadjuvant trials hold the most promise in identifying and validating them. This is because they can collect multiple samples from resectable HCC patients across stages, especially with multi-omics, bridging preclinical and clinical gaps.

The endoplasmic reticulum (ER) is a crucial organelle that orchestrates key cellular functions like protein folding and lipid biosynthesis. However, it is highly sensitive to disturbances that lead to ER stress. In response, the unfolded protein response (UPR) activates to restore ER homeostasis, primarily through three sensors: IRE1, ATF6, and PERK. ERAD and autophagy are crucial in mitigating ER stress, yet their dysregulation can lead to the accumulation of misfolded proteins. Cisplatin, a commonly used chemotherapy drug, induces ER stress in tumor cells, activating complex signaling pathways. Resistance to cisplatin stems from reduced drug accumulation, activation of DNA repair, and anti-apoptotic mechanisms. Notably, cisplatin-induced ER stress can dualistically affect tumor cells, promoting either survival or apoptosis, depending on the context. ERAD is crucial for degrading misfolded proteins, whereas autophagy can protect cells from apoptosis or enhance ER stress-induced apoptosis. The complex interaction between ER stress, cisplatin resistance, ERAD, and autophagy opens new avenues for cancer treatment. Understanding these processes could lead to innovative strategies that overcome chemoresistance, potentially improving outcomes of cisplatin-based cancer treatments. This comprehensive review provides a multifaceted perspective on the complex mechanisms of ER stress, cisplatin resistance, and their implications in cancer therapy.

Natural killer T cells (NKTs) are innate-like lymphocytes that are abundant in the liver and participate in liver immunity. NKT cells express both NK cell and T cell markers, modulate innate and adaptive immune responses. Type I and Type II NKT cells are classified according to the TCR usage, while they recognize lipid antigen in a non-classical major histocompatibility (MHC) molecule CD1d-restricted manner. Once activated, NKT cells can quickly produce cytokines and chemokines to negatively or positively regulate the immune responses, depending on the different NKT subsets. In liver transplantation (LTx), the immune reactions in a series of processes determine the recipients’ long-term survival, including ischemia-reperfusion injury, alloresponse, and post-transplant infection. This review provides insight into the research on NKT cells subpopulations in LTx immunity during different processes, and discusses the shortcomings of the current research on NKT cells. Additionally, the CD56-expressing T cells are recognized as a NK-like T cell population, they were also discussed during these processes.

Objective: In order to solve the problem of edible fungus species identification, an EfficientNet edible fungus image classification model based on convolution neural network is proposed. Methods: Firstly, the edible fungus images were collected and the datasets were made according to different equipment and shooting environment, and then the model performance was improved through model training skills and network skills. A YWeight weight attenuation method was proposed to control the effective learning rate, and the generalization performance of the model was affected by controlling the cross-boundary. Results: This method makes EfficientNet-B0 obtain 79.82% （+0.85%） top-1 accuracy on the self built dataset YMushroom, and only 78.97% in the default training process. On the public dataset fungus, the accuracy of EfficientNet-B0 was 87.62% （+0.78%） and the original training accuracy was 86.84%. Conclusion: Experiments show that by adjusting the super parameters, the model finds a near optimal solution, and improves the performance of the edible fungus image classification model through weight attenuation, which provides a basis for the automatic management of edible fungus planting base in the future.

【Objective】 Humanity and temperature are two factors affecting microbial communities not only in terrestrial systems but also in aquatic ecosystems. Taking Nanhai lake in cold-arid Baotou as an example, this paper analyzes the relationship between phytoplankton community and eutrophication in the lake. 【Method】 Water samples were taken from December 2017 to November 2018 from the lake. Phytoplankton community in each sample was counted. The ecological breadth and overlap of the dominant phytoplankton species were described by the niche analysis method, from which we calculated the effect of water environmental factors on phytoplankton community using the grey relational analysis. 【Result】 The dominant phytoplankton species detected from the water samples were 7 phyla, 38 genera and 95 species during the frozen period, and 7 phyla, 47 genera, 106 species during the unfrozen period. The main phytoplankton community comprises cyanobacteria-green algae-diatom. The niche breadth and niche overlap of the dominant species during the frozen period were smaller than those during the unfrozen period, and the competition of phytoplankton for resources was strong during the unfrozen period. The gray correlation analysis showed that the chemical oxygen demand (COD) and pH of the water were strongly correlated with phytoplankton density. Total phosphorus (TP) had a great impact on change in the phytoplankton population during the frozen period, while water temperature impacts the phytoplankton population change during the unfrozen period more greatly. 【Conclusion】 The dominant phytoplankton species in the Nanhai Lake are affected by a variety of ecological factors and vary with time. Organic pollutants and phosphorus nutrients are the main factors affecting the phytoplankton community.

Neuronal regeneration and functional recovery are severely compromised following traumatic brain injury (TBI). Treatment options, including cell transplantation and drug therapy, have been shown to benefit TBI, although the underlying mechanisms remain elusive. In this study, neural stem cells (NSCs) are transplanted into TBI-challenged mice, together with olfactory ensheathing cells (OECs) or followed by valproic acid (VPA) treatment. Both OEC grafting and VPA treatment facilitate the differentiation of NSCs into neurons (including endogenous and exogenous neurons) and significantly attenuate neurological functional defects in TBI mice. Combination of NSCs with OECs or VPA administration leads to overt improvement in axonal regeneration, synaptogenesis, and synaptic plasticity in the cerebral cortex in TBI-challenged mice, as shown by retrograde corticospinal tract tracing, electron microscopy, growth-associated protein 43 (GAP43), and synaptophysin (SYN) analyses. However, these beneficial effects of VPA are reversed by local delivery of N-methyl-D-aspartate (NMDA) into tissues surrounding the injury epicenter in the cerebral cortex, accompanied by a pronounced drop in axons and synapses in the brain. Our findings reveal that increased axonal regeneration and synaptogenesis evoked by cell grafting and VPA fosters neural repair in a murine model of TBI. Moreover, VPA-induced neuroprotective roles are antagonized by exogenous NMDA administration and its concomitant decrease in the number of neurons of local brain, indicating that increased neurons induced by VPA treatment mediate axonal regeneration and synaptogenesis in mice after TBI operation. Collectively, this study provides new insights into NSC transplantation therapy for TBI.

BackgroundLung metastasis (LM) is a common occurrence in patients with hepatocellular carcinoma (HCC), and it is associated with a poorer prognosis compared to HCC patients without LM. This study aimed to identify predictors and prognostic factors for LM in HCC patients as well as develop diagnostic and prognostic nomograms specifically tailored for LM in HCC patients.MethodsA retrospective analysis was conducted on HCC patients from the Surveillance, Epidemiology, and End Results (SEER) database, covering the period from 2010 to 2015. The study employed multivariate logistic regression analysis to identify risk factors associated with LM in HCC patients. Additionally, multivariate Cox proportional hazards regression analysis was utilized to investigate prognostic factors for HCC patients with LM. Subsequently, two nomograms were developed to predict the risk and prognosis of LM in HCC patients. The performance of the nomograms was evaluated through calibration curves, receiver operating characteristic (ROC) curves, and decision curve analysis (DCA).ResultThis retrospective study included a total of 5,934 patients diagnosed with HCC, out of which 174 patients were diagnosed with LM. Through multivariate logistic regression analysis, several independent risk factors for LM in HCC patients were identified, including tumor grade, tumor size, American Joint Committee for Cancer (AJCC) T stage, and AJCC N stage. Furthermore, multivariate Cox analysis revealed that tumor grade, delayed treatment, surgery, and radiation were independent prognostic factors for HCC patients with LM. To assess the predictive power of the developed nomograms, calibration curves, receiver operating characteristic (ROC) analysis, and decision curve analysis (DCA) were employed. The findings demonstrated that the nomograms exhibited satisfactory performance in both the training and validation sets. Additionally, the prognostic nomogram effectively stratified HCC patients with LM into low- and high-risk groups for mortality.ConclusionThese two nomograms optimally predicted the risk and prognosis of LM in HCC patients. Both nomograms have satisfactory performance. This would help clinicians to make accurate clinical decisions.

T cells are the common type of lymphocyte to mediate allograft rejection, remaining long-term allograft survival impeditive. However, the heterogeneity of T cells, in terms of differentiation and activation status, the effector function, and highly diverse T cell receptors (TCRs) have thus precluded us from tracking these T cells and thereby comprehending their fate in recipients due to the limitations of traditional detection approaches. Recently, with the widespread development of single-cell techniques, the identification and characterization of T cells have been performed at single-cell resolution, which has contributed to a deeper comprehension of T cell heterogeneity by relevant detections in a single cell – such as gene expression, DNA methylation, chromatin accessibility, surface proteins, and TCR. Although these approaches can provide valuable insights into an individual cell independently, a comprehensive understanding can be obtained when applied joint analysis. Multi-omics techniques have been implemented in characterizing T cells in health and disease, including transplantation. This review focuses on the thesis, challenges, and advances in these technologies and highlights their application to the study of alloreactive T cells to improve the understanding of T cell heterogeneity in solid organ transplantation.

To unify the source power of water migration, a pressure-suction element model of film water is constructed on the basis of the film water hydraulic driving force model and the surface adsorption force model. Model analysis shows that under the dual action of net suction and actual liquid pressure (or theoretical suction and actual ice pressure), the surface adsorption force can be generated, which drives the tangential migration of water along the surface of the substrate. In view of the fact that the surface adsorption force has nothing to do with the boundary conditions, it is suitable for any form of unfrozen water, and it is the unified source power of water migration. Based on this, the pressure?suction element model is introduced into the frozen fringe theory, and it is found that the actual ice pressure determines the temperature and position of the segregated ice formation, the theoretical suction determines the direction of water migration, and the surface adsorption force determines the velocity of water migration. Finally, substituting the main parameters from the Konrad (1980) test into the surface adsorption force equation, it is found that even if the temperature gradient increases from 0.1 ℃ /cm to 0.67 ℃ /cm, the sample height increases from 6.4 cm to 28 cm, as long as the segregation freezing temperature and the overburden pressure keep unchanged, the surface adsorption force is always constant at ?23 kPa, which verifies the correctness of the surface adsorption force equation. In short, the development of this model has important theoretical value and practical significance for improving the existing frost heave theory and guiding engineering practice.

BackgroundPancreatic neuroendocrine tumors (pNETs) are rare neuroendocrine neoplasms (NENs) for which little is known about their clinical features, treatment options, and survival prognosis. The purpose of this study is to evaluate the risk factors affecting the overall survival (OS) and cancer-specific survival (CSS) in patients with grade 1 pNETs (G1 pNETs) and to provide a new theoretical basis for clinical diagnosis and treatment.MethodsA retrospective analysis of individuals with G1 pNETs registered in the Surveillance, Epidemiology, End Results (SEER) database was performed. Risk factors affecting OS and CSS were analyzed using Kaplan-Meier analysis, Cox proportional hazards model, and Fine-Gray competing-risk model.ResultsA total of 751 patients were included, most of whom were white (77.2%) women (53.9%) under the age of 60 years (54.9%), of whom 66 died of pNETs (8.78%) and 34 died of other causes (4.52%). Patients who were older than 60 years at diagnosis (hazard ratio [HR] = 1.866, 95% confidence interval [CI]: 1.242-2.805) had worse OS. And stage in the regional extent (HR = 1.777, 95% CI: 1.006-3.137) or distance extent (HR = 4.540, 95% CI: 2.439-8.453) had worse OS. Patients who delayed treatment after diagnosis had shorter CSS (delayed treatment < 1 month: HR = 1.933, 95% CI: 0.863-4.333; delayed treatment ≥ 1 month: HR = 2.208; 95% CI:1.047-4.654). Patients with lymph node metastasis (HR = 1.989, 95% CI: 1.137-3.479) or distant metastasis (HR = 5.625, 95% CI: 1.892-16.726) had worse CSS. Acceptance of surgery can significantly improve the patient’s OS and CSS. OS (partial pancreatectomy [PP]: HR = 0.350, 95% CI: 0.182-0.672; pancreatectomy and duodenectomy [PD]: HR = 0.426, 95% CI: 0.222-0.815; total pancreatectomy [TP]: HR = 0.495, 95% CI: 0.193-1.267). CSS(PP: HR = 0.148, 95% CI: 0.0054-0.401; PD: HR = 0.332, 95% CI: 0.150-0.730; TP: HR = 0.69, 95% CI: 0.254-1.872).ConclusionAge and stage were identified as independent risk factors for OS. Delayed treatment, N stage and M stage were independent risk factors for CSS. Only surgery was identified as independent protective factors for OS and CSS.

HfO2– and ZrO2–based ferroelectric thin films have emerged as promising candidates for the gate oxides of next-generation electronic devices. Recent work has experimentally demonstrated that a tetragonal/orthorhombic (t/o-) phase mixture with partially in-plane polarization can lead to negative capacitance (NC) stabilization. However, there is a discrepancy between experiments and the theoretical understanding of domain formation and domain wall motion in these multi-phase, polycrystalline materials. Furthermore, the effect of anisotropic domain wall coupling on NC has not been studied so far. Here, 3D phase field simulations of HfO2– and ZrO2–based mixed-phase ultra-thin films on silicon are applied to understand the necessary and beneficial conditions for NC stabilization. It is found that smaller ferroelectric grains and a larger angle of the polar axis with respect to the out-of-plane direction enhances the NC effect. Furthermore, it is shown that theoretically predicted negative domain wall coupling even along only one axis prevents NC stabilization. Therefore, it is concluded that topological domain walls play a critical role in experimentally observed NC phenomena in HfO2– and ZrO2–based ferroelectrics.

Spin waves in magnetic materials are promising information carriers for future computing technologies due to their ultra-low energy dissipation and long coherence length. Antiferromagnets are strong candidate materials due, in part, to their stability to external fields and larger group velocities. Multiferroic antiferromagnets, such as BiFeO3 (BFO), have an additional degree of freedom stemming from magnetoelectric coupling, allowing for control of the magnetic structure, and thus spin waves, with the electric field. Unfortunately, spin-wave propagation in BFO is not well understood due to the complexity of the magnetic structure. In this work, long-range spin transport is explored within an epitaxially engineered, electrically tunable, 1D magnonic crystal. A striking anisotropy is discovered in the spin transport parallel and perpendicular to the 1D crystal axis. Multiscale theory and simulation suggest that this preferential magnon conduction emerges from a combination of a population imbalance in its dispersion, as well as anisotropic structural scattering. This work provides a pathway to electrically reconfigurable magnonic crystals in antiferromagnets.

Acute-on-chronic liver failure (ACLF) is a complex clinical syndrome, and patients often have high short-term mortality. It occurs with intense systemic inflammation, often accompanied by a proinflammatory event (such as infection or alcoholic hepatitis), and is closely related to single or multiple organ failure. Liver inflammation begins when innate immune cells (such as Kupffer cells (KCs)) are activated by binding of pathogen-associated molecular patterns (PAMPs) from pathogenic microorganisms or damage-associated molecular patterns (DAMPs) of host origin to their pattern recognition receptors (PRRs). Activated KCs can secrete inflammatory factors as well as chemokines and recruit bone marrow-derived cells such as neutrophils and monocytes to the liver to enhance the inflammatory process. Bacterial translocation may contribute to ACLF when there are no obvious precipitating events. Immunometabolism plays an important role in the process (including mitochondrial dysfunction, amino acid metabolism, and lipid metabolism). The late stage of ACLF is mainly characterized by immunosuppression. In this process, the dysfunction of monocyte and macrophage is reflected in the downregulation of HLA-DR and upregulation of MER tyrosine kinase (MERTK), which weakens the antigen presentation function and reduces the secretion of inflammatory cytokines. We also describe the specific function of bacterial translocation and the gut–liver axis in the process of ACLF. Finally, we also describe the transcriptomics in HBV-ACLF and the recent progress of single-cell RNA sequencing as well as its potential application in the study of ACLF in the future, in order to gain a deeper understanding of ACLF in terms of single-cell gene expression.

Tudor-SN (Tudor staphylococcal nuclease), also known as p100 or SND1 (Staphylococcal nuclease and Tudor domain containing 1), is a structurally conserved protein with diverse functions. Emerging evidence indicates that Tudor-SN plays an essential role in both physiological and pathological processes. Under physiological conditions, Tudor-SN regulates DNA transcription, RNA splicing, RNA stability, RNA interference, and RNA editing, and it is essential for a series of cellular biological events, such as cell cycle progression, cell metabolism, and cell survival, in response to harmful stimuli; thus, Tudor-SN functions as a “friend” to the body. However, Tudor-SN is highly expressed in most tumor cells. As an oncoprotein, Tudor-SN is closely associated with the initiation, development, and metastasis of tumors; thus, Tudor-SN functions as a “foe” to the body. What is the potential mechanism by which Tudor-SN switches from its role as “friend” to its role as “foe”? In this study, we review and summarize the available evidence regarding Tudor-SN protein structure, expression, modification, and mutation to present a novel model of Tudor-SN role switching. This review provides a comprehensive insight into the functional significance of the Tudor-SN protein under physiological and pathological conditions as well as corresponding therapeutic strategies that target Tudor-SN.

To build a vomit-free ward of scientific and standardized management mode, and to evaluate its clinical effects on preventing nausea and vomiting in patients undergoing chemotherapy.

A magnon is a collective excitation of the spin structure in a magnetic insulator and can transmit spin angular momentum with negligible dissipation. This quantum of a spin wave has always been manipulated through magnetic dipoles (that is, by breaking time-reversal symmetry). Here we report the experimental observation of chiral spin transport in multiferroic BiFeO3 and its control by reversing the ferroelectric polarization (that is, by breaking spatial inversion symmetry). The ferroelectrically controlled magnons show up to 18% modulation at room temperature. The spin torque that the magnons in BiFeO3 carry can be used to efficiently switch the magnetization of adjacent magnets, with a spin-torque efficiency comparable to the spin Hall effect in heavy metals. Utilizing such controllable magnon generation and transmission in BiFeO3, an all-oxide, energy-scalable logic is demonstrated composed of spin-orbit injection, detection and magnetoelectric control. Our observations open a new chapter of multiferroic magnons and pave another path towards low-dissipation nanoelectronics.

The solidification behavior and microstructures evolution of cast Ni-based superalloy K424 under different cooling rates were investigated by isothermal solidification quenching experiments and differential scanning calorimetry (DSC). The microstructures and segregation characteristics of K424 were analyzed at different isothermal temperatures and cooling rates using optical microscopy, scanning electron microscopy, and energy-dispersive spectrometry (EDS). The isothermal solidification, microstructure, and distribution characteristics of elements at the final solidification stage were also investigated, and the liquidus, solidus, and the formation temperatures of the main phases were evaluated. Furthermore, the influence of cooling rate on the morphology and size of MC carbides, (γ +γ') eutectic, and precipitated γ' phase were discussed. The results show that the solidification of the K424 alloy follows the sequence:(1) L → L + γ at 1345℃:the solidification begins with the formation of primary γ, and the liquidus temperature is 1345℃; (2) L → L + γ + MC at 1308℃:as the solidification continues, Ti and Nb are enriched in the liquid interdendrite, which results in the formation of MC carbides at 1308℃; (3) L → γ + (γ + γ') at 1260℃:the precipitation of the (γ + γ') eutectic occurs at about 1260℃ because of non-equilibrium solidification. Finally, the solidification ends with a solidus temperature of 1237℃. Furthermore, it is found that the precipitation of (γ + γ') eutectic at the interdendtitic regions is closely related to the cooling rate and the severe segregation behavior of Al and Ti into the residual liquid at the final solidification stage. With the increase of cooling rate, the quantity and size of MC carbides and eutectic first increase and then decrease. Moreover, with increasing cooling rate, γ' shapes transform from irregular petal-like structure to near cuboidal and spherical patterns, and the size scale of γ' precipitates decreases from 2 μm to 60 nm.

The surface of 20CrMnTi steel was strengthened by the square-spot laser shock peening(LSP) with 25J and 30J pulse energy. The layered style morphology, roughness, micro-hardness and residual compressive stress of the strengthened sample surface by LSP were test. The polarization curve and the corrosion morphology were investigated. The results show that, plastic deformation occurs in the surface after square-spot LSP, the surface roughness Ra of the specimens reduces to 0.433μm, and micro-hardness improves, great residual compressive stress is formed. The appropriate laser power density of LSP increases the density of the strengthened layer and passive film on the surface, and the transverse residual compressive stress makes the passive film more stable, and improves the corrosion resistance of materials. But the too large laser power density will cause the generation of pit defects in the material surface and the ablation of Al foil. Thus the Cl- is accumulated at the pit defects, the local tensile stress is generate on the surface of the material, and the surface passive film on the material is destroyed, and degrade the performance of corrosion resistance of the material.

The air environment strongly influences the damage behaviors of superalloys at high temperatures. To investigate the microscopic damage mechanisms during high-temperature fatigue crack growth in standard heat-treated GH4169 superalloys, low-cycle-fatigue crack growth tests were conducted at 650℃ with initial stress intensity factor ΔK=30 MPa·m1/2 and stress ratio R=0.05 under the air environment. The fracture surface, outside surface, and central sectioned surface of the specimen were observed and analyzed using scanning electron microscopy (SEM) and energy-dispersive spectrometry (EDS). The results show that the main fatigue crack initiates and propagates intergranularly, followed by the appearance of intergranular secondary cracks, whose quantity and length increase along the propagating direction of the main crack. In the rupture stage, a dimpled morphology appears on the fracture surface. Oxidation occurs at the interfaces between δ phases and the matrix during the fatigue crack propagation process, which leads to secondary cracks propagating along the interfaces. This leads to their inflection, which in turn retards their propagation. A grain-boundary oxidation damage zone exists at the outside surface of the specimen near the main crack. The size and degree of grain-boundary cracking increase along the propagating direction of the main crack.

Equilibrium phases in alloy A286 and the influence of element contents on gamma prime (γ′) and carbides were studied by Thermo-Calc calculation. The phase equilibria, solidification behavior, and precipitation behavior of equilibrium phases were investigated. In the results, Al is considered as the critical element for γ′ phase control, and C is the vital element for the regulation of MC and M23C6 phases. The influence extents of different elements on the transition temperature and the maximum content of γ′ phase, MC phases, and M23C6 phases are determined in order as Al>Ti>Cr>Mo, C>Ti>Ni>Cr>Mo, and C>Ni>Cr>Mo, respectively.

The influence of non-metallic inclusion on the performance of steels is closely related to the characteristic parameters. The in-situ scanning electron microscope (SEM) observation results of the crack initiation induced by TiN inclusion under tensile and fatigue loads in the ultra-high strength steel were analyzed. The stress fields of the inclusions and nearby matrix were then calculated using the MSC Marc finite element analysis software. Subsequently, the stress and strain fields of the TiN inclusions with different characteristic parameters and the nearby matrix were simulated. The results show that the mechanical behavior of the inclusions and the nearby matrix can be explained and predicted by finite element method. The maximum stress concentration is located around the sharp angle of a triangle inclusion. The position of the high-stress region in a rectangle inclusion is affected by the angle between the inclusion and the load direction. The position of the maximum stress in the matrix changes from the outer-inclusion region to the inter-inclusion region with the increase of the inter-inclusion distance. The high-stress region near the free surface results from the sub-surface inclusions, and the position of the maximum stress is affected by the distance from the inclusion to the free surface and the inclusion size.

Antiferromagnets have attracted significant attention in the field of magnonics, as promising candidates for ultralow-energy carriers for information transfer for future computing. The role of crystalline orientation distribution on magnon transport has received very little attention. In multiferroics such as BiFeO3 the coupling between antiferromagnetic and polar order imposes yet another boundary condition on spin transport. Thus, understanding the fundamentals of spin transport in such systems requires a single domain, a single crystal. We show that through Lanthanum (La) substitution, a single ferroelectric domain can be engineered with a stable, single-variant spin cycloid, controllable by an electric field. The spin transport in such a single domain displays a strong anisotropy, arising from the underlying spin cycloid lattice. Our work shows a pathway to understanding the fundamental origins of magnon transport in such a single domain multiferroic.

Bismuth ferrite has garnered considerable attention as a promising candidate for magnetoelectric spin-orbit coupled logic-in-memory. As model systems, epitaxial BiFeO3 thin films have typically been deposited at relatively high temperatures (650-800 °C), higher than allowed for direct integration with silicon-CMOS platforms. Here, we circumvent this problem by growing lanthanum-substituted BiFeO3 at 450 °C (which is reasonably compatible with silicon-CMOS integration) on epitaxial BaPb0.75Bi0.25O3 electrodes. Notwithstanding the large lattice mismatch between the La-BiFeO3, BaPb0.75Bi0.25O3, and SrTiO3 (001) substrates, all the layers in the heterostructures are well ordered with a [001] texture. Polarization mapping using atomic resolution STEM imaging and vector mapping established the short-range polarization ordering in the low temperature grown La-BiFeO3. Current-voltage, pulsed-switching, fatigue, and retention measurements follow the characteristic behavior of high-temperature grown La-BiFeO3, where SrRuO3 typically serves as the metallic electrode. These results provide a possible route for realizing epitaxial multiferroics on complex-oxide buffer layers at low temperatures and opens the door for potential silicon-CMOS integration.

Hot tearing tends to occur when K424 superalloy is used for a turbocharger turbine wheel. To solve this problem,the alloy characteristics of K424 and K418 superalloys and the factors impacting the susceptibility to hot tearing were studied by microstructure observations and casting simulations. The research proposed the main factors which affected the susceptibility to hot tearing and also the method to reduce hot tearing in the turbine wheel. It is found that the susceptibility to hot tearing of the turbine wheel is influenced by both the alloy characteristics and casting characteristics. K424 superalloy shows a higher susceptibility to hot tearing when compared with K418. Because of high amount of aluminum and titanium in K424 superalloy,the size and the amount of γ + γ' eutectics increase,resulting in more prior forming and propagating areas of hot tearing. On the other hand,due to a smaller thickness and a larger curvature change in the blade margin of the turbine wheel,the uneven distribution of the thermal stress is induced in the end of the solidification process,which leads to hot tearing in this paper. In order to decrease the susceptibility to hot tearing of the turbine wheel,the contents of aluminum and titanium should be controlled,and the reasonable technological parameters of casting should be set to ensure the final effect.

To study the microstructural stability of GH4169C alloy with high content of phosphorus and niobium, the microstruc-ture and hardness of GH4169C alloy and GH4169 alloy after long time aging were comparatively analyzed in this paper. These two su-peralloys were subjected to aging treatment at 600, 650, 704 and 720℃ for different times from 30 h to 10000 h. The microstructural evolution of the alloys was characterized by using a field emission scanning electron microscope and a Brinell hardness tester. The re-sults indicate that, at the service temperature of 650℃, GH4169 alloy and GH4169C alloy show excellent structure stability. Howev-er, above the service temperature, GH4169 alloy and GH4169C alloy have poor structure stability. In a short period of time, the two alloys lose stability. In contrast, the microstructure stability of GH4169C alloy is higher than that of GH4169 alloy with aging at 704℃, while GH4169C alloy shows a lower stability compared with GH4169 alloy at 720℃. It is thought that the stability of γ'phase in GH4169C alloy increases with increasing Nb and P contents. GH4169C alloy shows a better microstructure stability than GH4169 alloy at 704℃. However, the content of δphase will also increase with increasing Nb content, leading to the decrease in microstructure sta-bility of GH4169C alloy. At ultrahigh temperature (720℃), the microstructure stability of GH4169C alloy is inferior to GH4169 al-loy. This means that, compared with GH4169 alloy, the modified GH4169C alloy can be used in a higher temperature, whereas the temperature increase is limited, the microstructure stability of GH4169C alloy will decrease at ultrahigh temperature.

In order to simulate low vacuum experimental environment,Tb0.27Dy0.73Fe1.91 alloy round bars were prepared through melting with Tb, Dy and Fe elements, directional solidification and heat treatment in low vacuum environment. The magnetostriction of the alloy rods was tested. The microstructures and the causes of defects in the alloy were investigated. The results indicate that under the low vacuum experimental environment, there are plenty of twin dendritic lamellar microstructures and ordinary twin microstructures are generated in alloy, among which the mechanical properties and "jump" effect of twin dendritic lamellar structures are good, while the ordinary twins are bad to the magnetostrictive property in the alloy. REFe2 and REFe3 coupling phase is the main phase in the matrix, the burning loss of rare earth elements lead variations in chemical composition, resulting coupling growth with REFe3 phase and REFe2 phase. The thermal stress and the burning loss of rare earth elements segregate at grain boundaries resulting in the presence of micro-cracks and micro-holes. These microstructures and defects generate bad impact on mechanical properties and magnetostriction of TbDyFe alloy rods.

The fatigue crack growth rates of powder metallurgy (P/M) superalloy FGH97 with different grain sizes, γ' phase sizes and Hf contents were measured at a 650℃ high temperature condition and compared with those of FGH95 and FGH96 alloys. The fatigue fracture behavior characteristic of FGH97 alloy in each stage was analyzed by the quantitative analysis method. It is found that FGH97 alloy with coarser grains has a lower fatigue crack growth rate. Reasonable match of secondary and tertiary γ' phases and Hf addition can get a higher fatigue life. Compared with FGH95 and FGH96 alloys, FGH97 alloy has the highest fatigue cack intiation resistance and exihibits the lowest fatigue crack propagation rate at high temperature.

A standard heat treatment(1105℃/4 h/(oil cooling) + 650℃/24 h/(air cooling) + 760℃/16 h/(air cooling)) and a subsequent long term exposure at temperatures of 720℃ for 0-5000 h and 800℃ for 0-1000 h were proposed to investigate the microstructural evolution of γ' precipitates in GH720 Li alloy. The size,morphology and quantity of the primary γ' phase have no significant variation at 720℃. However,at the same temperature,obvious grain coarsening and the grain size inhomogeneity of secondary γ'particles appear with the aging time up to 200 h and 500 h,respectively. The descending slope of hardness decreases first and when the aging time exceeds 500 h it flattens. At 800℃,the primary γ' phase coarsens after 500 h of aging,while both obvious grain coarsening and the grain size inhomogeneity of secondary γ' particles happen after 100 h of long term exposure. The descending slope of hardness decreases first,and unlike the results at 720℃,it is still downward when the aging time exceeds 500 h. The coarsening behavior is controlled by lattice diffusion. There shows a linear relationship between the average radius of the γ' phase and the cube root of aging time,which accords with the L-S-W(Lifshiz-Slyozov-Wanger) theory.

Traditionally, optical microscopy is used to visualize the morphological features of pathogenic bacteria, of which the features are further used for the detection and identification of the bacteria. However, due to the resolution limitation of conventional optical microscopy as well as the lack of standard pattern library for bacteria identification, the effectiveness of this optical microscopy-based method is limited. Here, we reported a pilot study on a combined use of Structured Illumination Microscopy (SIM) with machine learning for rapid bacteria identification. After applying machine learning to the SIM image datasets from three model bacteria (including Escherichia coli, Mycobacterium smegmatis, and Pseudomonas aeruginosa), we obtained a classification accuracy of up to 98%. This study points out a promising possibility for rapid bacterial identification by morphological features.

The microstructure of as-cast GH625 alloy was investigated on the basis of experimental methods such as Thermo-Calc software,scanning electron microscopy and energy dispersive spectroscopy. The effect of casting temperature on the microstructure was also analyzed by comparing different samples. The microstructure of as-cast GH625 alloy is a dendritic structure and M6C carbides accompanied with δ phase precipitate in the interdendritic area. Both primary dendrite arm spacing(λ1) and second dendrite arm spacing(λ2) increase with the increase of casting temperature; however,the microsegregation is affected by both diffusion distance and diffusion time. The comprehensive interaction of these two factors leads to the greatest microsegregation degree of Nb at 1420℃,which contributes to δ phase precipitation in the interdendritic area. As a result,diffusion distance and diffusion time should be comprehensively considered in making the casting process,so as to choose a proper casting temperature(or cooling rate).

We present a massively parallel, 3D phase-field simulation framework for modeling ferroelectric materials based scalable logic devices. This code package, FerroX, self-consistently solves the time-dependent Ginzburg Landau (TDGL) equation for ferroelectric polarization, Poisson's equation for electric potential, and charge equation for carrier densities in semiconductor regions. The algorithm is implemented using the AMReX software framework [1], which provides effective scalability on manycore and GPU-based supercomputing architectures. We demonstrate the performance of the algorithm with excellent scaling results on NERSC multicore and GPU systems, with a significant (15×) speedup on the GPU using a node-by-node comparison. We further demonstrate the applicability of the code in simulations of ferroelectric domain-wall induced negative capacitance (NC) effect in Metal-Ferroelectric-Insulator-Metal (MFIM) and Metal-Ferroelectric-Insulator-Semiconductor-Metal (MFISM) devices. The charge (Q) v.s. voltage (V) responses for these 3D structures clearly indicate stabilized negative capacitance with multidomain formation, which is corroborated by amplification of the voltage at the interface between the ferroelectric and dielectric layers.