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Abstract [Objective] The study aims to identify and describe a new species Cinnamomum huarum (Lauraceae), which was collected from Nanjian, Yunnan of China. [Methods] This species was confirmed as a new taxa by morphological comparison with morphologically similar species and molecular phylogenetic study based on chloroplast genome data. [Results] The new species was similar to C. chago: Pinnately veined, leaves opposite or subopposite, long acumen, branchlets sparsely puberulent, terminal bud densely pubescent, leaf blade gray white abaxially and puberulent, margin undulate and fruit oblate. The chloroplast genome size of this species was 154 078 bp, which was 1 325 bp longer than C. chago and 1 348 bp longer than C. pittosporoides, having an extra 678 bp fragment in the inverted repeat region compared to C. chago and C. pittosporoides. In the phylogenetic tree constructed with whole chloroplast genome of 36 Lauraceae species, C. huarum formed an independent parallel branch with C. pittosporoides and other species. [Conclusion] Both the morphological and phylogenetic research indicate that C. huarum is a distinct species.

We conducted a systematic review to compare the diagnostic utility of ultrasound-guided transperineal (TP) and transrectal (TR) prostate biopsy methods for prostate cancer detection.

According to the analysis of the corrosion products from the Bohai oilfield sewage system,the main causes of corrosion were the high concentration of ferric ion and amide chemicals in the sewage. Among those causes, the under-deposit corrosion caused by a large amount of iron scale was the most important cause of corrosion and the key point of pitting corrosion. Based on the above situation, the corrosion of the oilfield was well controlled by continuously by adding highly efficient Fe ion stabilizer and highly efficient descaler while control of the return liquid.

To enhance the rock-crushing efficiency and drilling life of impregnated diamond drill bits，a strategy was proposed for the localized heterogenization of the drill bit matrix through composite electroplating reinforcement of diamond particles，separating the protrusion effect of diamonds in the drill bit matrix from their encapsulation strength.Diamond particles were strengthened by electroless plating and composite electroplating.Subsequently，the diamond drill head body was prepared through hot pressing sintering.Studies were conducted on the performance changes of the composite electroplating strengthened diamond particles，the friction and wear characteristics of the drill head body，and the protrusion state and binding interface of the diamonds within the drill head body.Results showed that a modified metal coating was obtained on the surface of diamond particles strengthened by composite electroplating.The morphology of the coating was dense and uniform，with good bonding with diamond.The composite electroplating strengthened diamond particles effectively improved the surface wettability and impact resistance of diamond.The heterogeneous matrix structure ensured the slow protrusion process and the protrusion height of the diamond.The composite electroplating strengthened diamond particles effectively improved the comprehensive performance of the diamond bit.

The newly-developed Ni–28W–6Cr alloy is the structural material for the next-generation molten salt reactor (MSR). Due to the detrimental effects of welding hot cracks on the quality of welded structures, it is essential to study the hot cracking behavior and mechanism to achieve the qualified Ni–28W–6Cr alloy welded joint. This paper analyzes the characteristics of the dynamic cracking behavior of welding hot cracks using a high-speed camera. The microstructure, morphology, and cracking mechanism of hot cracks are studied. The results show that solidification cracks and liquation cracks occur in the welded joint. According to the propagation direction of the hot crack, there are longitudinal cracks and transverse cracks, respectively. The quantity and length of hot cracks increase with the laser power. The laser welded joint's hardness value fluctuates from 200 HV to 260 HV. The width of heat affected zone (HAZ) is approximately 0.5–1 mm, and there is a slight softening zone in the HAZ. Meanwhile, the hardness of the weld metal is the highest in the welded joint. The solidification cracks tend to initiate and crack along the solidification grain boundary, which is mainly related to the thermal stress caused by the welding process and the weak bonding strength of grain boundaries caused by the element segregation and precipitation at the grain boundary. Liquation cracking is mainly affected by welding thermal stress and element segregation at the grain boundary in the HAZ. However, the eutectic carbides play the role of inhibiting the propagation of liquation cracks.

The purpose of this study is to investigate the efficacy of bilateral upper-limb training (BULT) in helping people with upper-limb impairments due to stroke or brain illness regain their previous level of function. Patients recuperating from a stroke or cerebral disease were given the option of undergoing BULT or conventional training to enhance their upper-limb function. Participants were randomly allocated to one of the several different fitness programs. Results from the action research arm test, Box and block test, Wolf motor function test, Fugal–Meyer evaluation, and any other tests administered were taken into account. Some researchers have found that exercising with BULT for just 30 min per day for 6 weeks yields significant results. There were a total of 1,411 individuals from 10 randomized controlled trials included in this meta-analysis. Meta-analysis findings revealed that biofeedback treatment outperformed conventional rehabilitation therapy in reducing lower leg muscular strain, complete spasm scale score, electromyography score, and inactive ankle joint range of motion. An analysis of the literature found that BULT improved limb use in people who had suffered a stroke and hemiplegia but it did not provide any additional benefit over unilateral training.

Abstract Background The study aimed to establish a prognostic survival model with 8 pyroptosis-and-cuproptosis-related genes to examine the prognostic effect in patients of hepatocellular carcinoma (HCC). Methods We downloaded gene expression data and clinical information of HCC patients from The Cancer Genome Atlas (TCGA), International Cancer Genome Consortium (ICGC) and Gene Expression Omnibus (GEO). The clustering analysis and cox regression with LASSO were used for constructing an 8 PCmRNAs survival model. Using TCGA, ICGC and GEO cohort, the overall survival (OS) between high- and low- risk group was determined. We also evaluated independent prognostic indicators using univariate and multivariate analyses. The relatively bioinformatics analysis, including immune cell infiltration, function enrichment and drug sensitivity analyses, was performed as well. The gene expression of 8 PCmRNAs in vitro were validated in several HCC cell lines by qRT-PCR and Western blot. The relationship between GZMA and Fludarabine were further checked by CCK-8 assay. Results The survival prognostic model was constructed with ATP7A, GLS, CDKN2A, BAK1, CHMP4B, NLRP6, NOD1 and GZMA using data from TCGA cohort. The ICGC and GEO cohort were used for model validation. Receiver operating characteristic (ROC) curves showed a good survival prediction by this model. Risk scores had the highest predictable value for survival among Stage, Age, Gender and Grade. Most Immune cells and immune functions were decreased in high-risk group. Besides, function enrichment analyses showed that steroid metabolic process, hormone metabolic process, collagen − containing extracellular matrix, oxidoreductase activity and pyruvate metabolism were enriched. Potential drugs targeted different PCDEGs like Nelarabine, Dexamethasone and Fludarabine were found as well. ATP7A, GLS, CDKN2A, BAK1, CHMP4B, NOD1 were upregulated while NLRP6 and GZMA were downregulated in most HCC cell lines. The potential therapy of Fludarabine was demonstrated when GZMA was low expressed in Huh7 cell line. Conclusion We constructed a novel 8-gene (ATP7A, GLS, CDKN2A, BAK1, CHMP4B, NLRP6, NOD1 and GZMA) prognostic model and explored potential functional information and microenvironment of HCC, which might be worthy of clinical application. In addition, several potential chemotherapy drugs were screened and Fludarabine might be effective for HCC patients whose GZMA was low expressed.

In this article, we study a class of variational inequality problems with non-Newtonian polytropic parabolic operators. We introduce a mapping with an adjustable parameter to control the polytropic term, which exactly meets the conditions of Leray-Schauder fixed point theory. At the same time, we construct a penalty function to transform the variational inequality into a regular parabolic initial boundary value problem. Thus, the existence is treated with a Leray-Schauder fixed point theory as well as a suitable version of Aubin-Lions lemma. Then, the uniqueness and stability of the solution are analyzed.

Al–Si coated 22MnB5 steels are one of the most important lightweight materials for automotive weight reduction and safety improvement due to its advantages of light weight, high strength and good formability at high temperature. Considering the formation of α-ferrite caused by the Al–Si coating deteriorating the weld mechanical performance, the common way in the automotive industry is to remove the Al–Si coating prior to laser welding. In this work, a patented laser-filler wire welding process was developed with a high strength steel wire to inhibit the formation of α-ferrite and achieve high quality laser weld in Al–Si coated 22MnB5 without the requirement of removing the Al–Si coating. A formula for calculating the average content of Al element in the fusion zone was provided and verified by experiment. Experimental results show that Al segregation in the fusion zone with the designated filler wire was reduced, and the microstructure was full martensite with high dislocation density. The strain of the welded joint was concentrated in the hot-stamped base metal (HSBM) and fractured in an obvious necking during the tensile shear test. The tensile strength and elongation of the welded joint with filler wire increased by 7.5% and 183.9% compared with that without filler wire.

BackgroundWith the development of human aerospace industry, it is necessary to develop propulsion systems suitable for different space mission scenarios. MegnetoPlasmaDynamic thruster (MPDT), which is similar to the principle of magnetic confinement fusion, is a typical representative of electromagnetic thruster, which stands out among many electric thrusters because of its superior performance in thrust power ratio and specific impulse. Anode power deposition is the result of the interaction between plasma and wall during MPDT operation. It is one of the main mechanisms of power loss of this type of thruster, accounting for 40%~90% of the total power, which seriously reduces the efficiency of thruster.PurposeThis study aims to solve the problem of low efficiency of thruster by investigating the influence of anode radius on the efficiency of thruster from the perspective of anode power deposition.MethodsFirst of all, based on MagnetoHydroDynamic (MHD) equations, numerical models for radial discharge parameters and physical model for anode power deposition were established. Then, the influences of anode radius on discharge parameters, anode power deposition and anode power deposition fraction were studied on the basis of these models by numerical calculation method. Finally, a water-cooled structure anode was designed, and the effectiveness of its heat dissipation structure was verified by thermal simulation.ResultsThe results show that with the increase of anode radius, the electron density and ion velocity are increased, the anode power deposition fraction is decreased whilst the anode power deposition is increased. The thruster efficiency is improved by increasing the anode radius. The thermal simulation results show that when the input power deposition of the water-cooled structure anode is about 3 kW, the corresponding temperature difference of the anode cooling water is 5 K.ConclusionsThis study verifies the reliability of the physical model of anode power deposition, indicating that increasing the anode radius is an effective means to improve the efficiency of the thruster.

BackgroundElectric propulsion systems, compared to traditional chemical propulsion, offer longer operational lifespans and lower fuel consumption in space missions, garnering significant attention in recent years. However, for high-power Hall effect electric thrusters developed based on controlled fusion concepts, measuring thrust proves challenging due to the high-temperature environments required for ionizing propellants in electric thruster, resulting in the generation of hot plasma plumes during operation. As a result, traditional thrust measurement methods are unable to accurately measure the thrust.PurposeThis study aims to accurately measure thrust during ground testing of electric thrusters for precise control of the spacecraft's attitude and orbit maintenance.MethodsFirstly, a thrust measurement platform based on flexible beam structure was designed and implemented with capability of measuring the thrust generated by electric thrusters in high-temperature. Simultaneously, a calibration system was built to verify the stability and repeatability of the thrust measurement results. Then, simulation analysis was conducted on the structural mechanics and thermal coupling field of the thrust measurement system under different operating conditions. Finally, the variable specific impulse magnetoplasma rocket (VASIMR) was taken for experimental thrust measurement of its electric propulsion system.ResultsThe experimental results of VASIMR indicate the thrust is 266.5 mN measured in real time at the central magnetic field intensity of 0.2 T with a mass flow rate of 20 mg∙s-1.ConclusionsThe thrust measurement platform based on the bending beam structure can meet the measurement requirements of VASIMR, providing valuable references for subsequent experiments.

Al–Si coated 22MnB5 steel is a lightweight material that helps significantly reduce vehicle weight and fuel consumption. In this article, the effect of different oscillation frequencies on the fraction of α-ferrite, the cross-sectional shape, microstructure and mechanical properties of laser welded Al–Si coated 22MnB5 steel was investigated. The results showed that after stamping, the fraction of α-ferrite in the fusion zone can be significantly reduced from 47.9% to 2.2% by oscillating laser beam welding compared to static laser beam welding with oscillation frequency and amplitude equal to zero. When the oscillating frequency was increased from 0 to 320 Hz, the cross-sectional shape of the weld changed from “X'' to “Y'', and the tensile strength and elongation of the welded joint was firstly increased and then decreased from the minimum value of (426.45HV, 1159.92 MPa, 1.14%) to the maximum value of (476.98HV, 1521.39 MPa and 2.76%). The formation of α-ferrite along the strip distribution near the upper surface of the fusion zone of static laser beam welding and oscillating laser beam welding after hot stamping, which led to stress concentration and eventual failure. Under the tensile-shear load, the cracks in the weld of static laser beam welding and oscillating laser beam welding were initiated on the massive α-ferrite location in the top surface of the fusion zone and expanded to the bottom of the weld.

Objective To investigate the difference of electroreactivity and electrocoagulation of commonly used interventional materials. Methods The resistance of different types of micro⁃guide wire and spring coil are measured with a multimeter to obtain the physical parameters reflecting the conductivity. The in vitro electrolytic gas production experiment was carried out with physiological saline and isolated arterial blood of New Zealand white rabbits as the medium, the gas production data were obtained, and the thrombus adhesion on the surface of the materials was observed by scanning electron microscopy. Results The resistance measurement results showed ASAHI, SilverSpeed, Traxcess micro⁃guide wire and Axium spring coil have good conductivity, the electrolytic gas production could occur after power⁃up, and the voltage was positively correlated with gas production speed (P＜0.05, for all). The results of in vitro arterial blood electrocoagulation showed that better thrombosis quality could be obtained by increasing the voltage. Conclusions The micro⁃guide wire and spring coil used for intra⁃arterial electrocoagulation can preliminarily selected by resistance measurement, and the voltage is the key factor to determine the electrical reaction intensity and thrombosis quality.

Inconsistent findings have been reported regarding the association between elevated plasma total homocysteine (tHcy) and the risk of different types of strokes. We conducted this meta-analysis to identify the association between tHcy and different kinds of strokes or recurrences of strokes, and provide evidence for preventing.

Neural stem cells (NSCs) transplantation is a promising therapeutic strategy for ischemic stroke. However, significant cell death after transplantation greatly limits its effectiveness. Poly (trimethylene carbonate)15-F127-poly (trimethylene carbonate)15 (PTMC15-F127-PTMC15, PFP) is a biodegradable thermo-sensitive hydrogel biomaterial, which can control drug release and provide permissive substrates for donor NSCs. In our study, we seeded NSCs into PFP polymer scaffold loaded with three neurotrophic factors, including brain-derived neurotrophic factor, nerve growth factor, and Neurotrophin-3. And then we transplanted this NSCs-polymer scaffold in rat brains 14 days after middle cerebral artery occlusion. ELISA assay showed that PFP polymer scaffold sustained releasing three neurotrophic factors for at least 14 days. Western Blot and fluorescence immunostaining revealed that NSCs-polymer scaffold transplantation significantly reduced apoptosis of ischemic penumbra and promoted differentiation of the transplanted NSCs into mature neurons. Furthermore, infarct size was reduced, and neurological performance of the animals were improved by the transplanted NSCs-polymer scaffold. These results demonstrate that PFP polymer scaffold loaded with neurotrophic factors can enhance the effectiveness of stem cell transplantation therapy, which provides a new way for cell transplantation therapy in ischemic stroke.

ObjectiveThe optimal treatment approach for hemorrhagic moyamoya disease (HMMD) remains a topic of debate, particularly regarding the comparative efficacy of revascularization versus conservative treatment. Our study, which included a single-center case series and a systematic review with meta-analysis, aimed to determine whether surgical revascularization is associated with a significant reduction in postoperative rebleeding, ischemic events, and mortality compared to conservative treatment among East Asian HMMD patients.MethodsWe conducted a systematic literature review by searching PubMed, Google Scholar, Wanfang Med Online (WMO), and the China National Knowledge Infrastructure (CNKI). The outcomes of surgical revascularization and conservative treatment, including rebleeding, ischemic events and mortality, were compared. The authors' institutional series of 24 patients were also included and reviewed in the analysis.ResultsA total of 19 East Asian studies involving 1,571 patients as well as our institution's retrospective study of 24 patients were included in the study. In the adult patients-only studies, those who underwent revascularization had significantly lower rates of rebleeding, ischemic events, and mortality compared to those who received conservative treatment (13.1% (46/352) vs. 32.4% (82/253), P < 0.00001; 4.0% (5/124) vs. 14.9% (18/121), P = 0.007; and 3.3% (5/153) vs. 12.6% (12/95), P = 0.01, respectively). In the adult/pediatric patients' studies, similar statistical results of rebleeding, ischemic events, and mortality have been obtained (70/588 (11.9%) vs. 103/402 (25.6%), P = 0.003 or

Surface drag reduction technologies can significantly reduce the resistance during ship navigation, enhancing speed, efficiency and adaptability under various operating conditions. This paper uses numerical simulation technology to analyze the drag reduction characteristics of grooved and grooves-microbubbles coupling surface, focusing on the effects of groove width, gas flow rate, and liquid flow velocity on the drag reduction performance. The research results indicate that the grooved surface is suitable for full surface drag reduction at velocity below 3 m/s with a maximum drag reduction rate of 4.02%. Microbubbles can greatly improve the drag reduction effect of the grooved surface, and the drag reduction effect of the coupling surface gradually increases with the gas flow rate increases. The maximum drag reduction rate can reach 89.86% at the gas inlet velocity of 1 m/s. The liquid flow velocity has a significant impact on the drag reduction. In both the groove model and the coupling model, the drag reduction rate initially rises and then declines with the liquid flow velocity increases.

Abstract Background Acute respiratory distress syndrome (ARDS) is a rapidly progressive and fatal respiratory failure disease that often occurs in critically ill patients. Since ARDS is associated with immune dysregulation and coagulation abnormalities, it is necessary to identify an appropriate predictor that can accurately predict ARDS mortality based on its pathophysiology. Therefore, this study aimed to evaluate the clinical value of neutrophils to lymphocytes and platelets ratio (N/LPR) in predicting 28-day mortality in ARDS patients. Methods From July 2018 to October 2021, the medical records of ARDS patients were retrospective reviewed. Neutrophil count, lymphocyte count, and platelet count were collected, and the neutrophil-to-lymphocyte ratio (NLR) and N/LPR were calculated. Multivariate logistic regression analyses were performed to identify independent predictors of 28-day mortality in ARDS. Receiver operating characteristic (ROC) curve with the area under curve (AUC) was used to evaluate optimal cut-off values for 28-day mortality in ARDS. Kaplan–Meier analysis was used to estimate the 28-day survival probabilities stratified by optimal cut-off values of N/LPR and NLR. Results A total of 136 ARDS patients were included in this study and were further divided into survivors (n = 69) and non-survivors (n = 67) groups according to their survival status on day 28. There were no significant differences between the two groups in age, sex, history of smoking and drinking, comorbidities, and reasons of admission (P > 0.05). Non-survivors had significantly higher neutrophil counts, NLR and N/LPR and had significantly lower platelet counts than survivors (P

The crack in adhesives is one of the common damage patterns in composite adhesive structures,which will affect the integrity of composite structures.In this paper,the single-lap bonded composite joints which are the common adhesive structures in aircraft are chosen as the study object.The three-dimensional numerical model is established with the bilinear cohesive constitutive relation characterizing the static crack propagation,and then the static model is extended to fatigue crack propagation model.The distribution of stress and strain,crack propagation and failure mechanism are studied by using the experiment and numerical methods.The results show that the strain of single-lap adhesive joints varies nonlinearly under static and fatigue loadings because of the eccentric tension.Due to the stress concentration,fatigue cracks appear on both ends of the lapped area firstly,and then extend to the central area until cover the whole lapped area.The static failure mode is cohesive failure,and the interface debonding failure is observed in fatigue fracture.

High-altitude satellites are visible to more ground station antennas for longer periods of time, its requests often specify an antenna set and optional service windows, consequently leaving huge scheduling search space. The exploitation of reinforcement learning techniques provides a novel approach to the problem of high-altitude orbit satellite range scheduling. Upper sliding bound of request pass was calculated, combining customized scheduling strategy with overall antenna effectiveness, a frame of satellite range scheduling for urgent request using reinforcement learning was proposed. Simulations based on practical circumstances demonstrate the validity of the proposed method.

Quenching and partitioning (Q&P) steels are among the most critical third-generation steels for realizing vehicle weight reduction and improving safety performance. It is critical for the structure durability to have an excellent fatigue life of the welds. In this study, Q&P1180 steel was laser spot welded (LSW) in order to evaluate the microhardness, mechanical properties, and fatigue behavior of its joints, which were compared with resistance spot welding (RSW). In both types of joining methods, the welded zone is composed of lath martensite with high microhardness value. Due to the martensite tempering, the sub-critical heat affected zone of Q&P RSW welds was soften, resulting in a decrease of 52 HV of microhardness than the LSW joint. The presence of stress concentration in the boundary influenced tensile strength and all-welded samples failed in the boundary. Furthermore, the fatigue limit of the RSW joint (1.139 kN) was about 91.5%t of the LSW joint (1.245 kN). Fatigue specimens of the LSW joint failed between the fusion zone and heat-affected zone because of their higher sensitivity to stress concentration than the RSW joint, resulting in double eyebrow failure and pull-out failure. Fatigue crack originated from the specimen surface and propagated through fatigue striations together with secondary cracks. In addition, it was found that the strength of the base metal has inconsequentially affected the fatigue life of the welds when these welds were produced by the same welding method and have similar geometries.

Advanced composites have been widely used in aerospace field and transportation field in ground due to their excellent mechanical properties. Fatigue damage and life prediction of composites have always been the important and difficult issues in the field of composite mechanics. In this paper, the maximum stress criterion and Puck criterion were extended to fatigue failure criterion, and the fatigue damage analysis model of composite laminates was established by combining the gradual degradation model of material properties, the regularized fatigue life analysis method and the fatigue damage accumulation theory. Then, the model was used to predict the damage evolution and failure mechanism of composite laminates, and the fatigue tests with three stress levels (55%, 60% and 65%) were conducted. The fatigue life and failure mode of the numerical results matches well with the test results. Under fatigue loadings, the fatigue damage initiated from free edges on both sides of the plate to the inside of the laminates. The matrix damage first appeared in the 90° plies on two free sides, then the matrix damage and fiber damage of 45° plies were induced. The fiber damage of 0° ply finally appears and rapidly spreads to the center of laminates until the damage covers the entire cross section.

Objective To probe into the level and clinical significance of anti-carbamylated protein （CarP） antibody in serologically negative patients with rheumatoid arthritis （RA）. Methods A total of 301 RA patients and 55 healthy controls were recruited. Demographic characteristics and clinical data including serum levels of rheumatoid factor （RF） and anti-cyclic citrullinated peptide （CCP） antibody were collected. Serum levels of IgG anti-CarP antibody were determined by ELISA. Results According to the 95th percentile of the anti-CarP antibody level in 55 healthy controls, the ceiling of normal value was ≤31 U/mL. Among 301 RA patients, the positive rates of RF, anti-CCP antibody and anti-CarP antibody were 74.8% （225/301）, 75.1% （226/301） and 15.9% （48/301）, respectively. The positive rates of anti-CarP antibody were 19.7% （15/76） in RA patients with negative RF and 20.0% （15/75） in RA patients with negative anti-CCP antibody, respectively. In negative-RF RA patients, additional detection of anti-CCP antibody could reduce the percentage of serologically negative RA patients by 39.5% （30/76）. Additional detection of anti-CarP antibody could lower the percentage by 19.7% （15/76）. Additional detection of both anti-CCP antibody and anti-CarP antibody could decrease the percentage by 50.0% （38/76）. In serologically negative RA patients （negative for both RF and anti-CCP antibodies）, additional detection of anti-CarP antibody could lower the percentage of serologically negative RA patients by 17.4% （8/46）. Conclusion Additional detection of anti-CarP antibody has supplementary value for the diagnosis of serologically negative RA which is currently a difficult issue in clinical practice.

Abstract Background Bone marrow mesenchymal stem cells have always been a heated research topic in bone tissue regeneration and repair because of their self-renewal and multi-differentiation potential. A large number of studies have been focused on finding the inducing factors that will promote the osteogenic differentiation of bone marrow mesenchymal stem cells. Previous studies have shown that macrophage exosomes or miRNA-26a-5p can make it work, but the function of this kind of substance on cell osteogenic differentiation has not been public. Methods M2 macrophages are obtained from IL-4 polarized bone marrow-derived macrophages. Exosomes were isolated from the supernatant of M2 macrophages and identified via transmission electron microscopy (TEM), western blotting, and DLS. Chondrogenic differentiation potential was detected by Alcian blue staining. Oil red O staining was used to detect the potential for lipogenic differentiation. And MTT would detect the proliferative capacity of cells. Western blot was performed to detect differential expression of osteogenic differentiation-related proteins. Results The results showed that M2 macrophage exosomes will promote bone differentiation and at the same time inhibit lipid differentiation. In addition, M2 macrophage-derived exosomes have the function of promoting the expression of SOX and Aggrecan suppressing the level of MMP13. The exosome inhibitor GW4689 suppresses miRNA-26a-5p in M2 macrophage exosomes, and the treated exosomes do not play an important role in promoting bone differentiation. Moreover, miRNA-26a-5p can enable to promote bone differentiation and inhibit lipid differentiation. miRNA-26a-5p can promote the expression of ALP (alkaline phosphatase), RUNX-2 (Runt-related transcription factor 2), OPN(osteopontin), and Col-2(collagen type II). Therefore, it is speculated that exosomal miRNA-26a-5p is indispensable in osteogenic differentiation. Conclusions The present study indicated that M2 macrophage exosomes carrying miRNA-26a-5p can induce osteogenic differentiation of bone marrow-derived stem cells to inhibit lipogenic differentiation, and miRNA-26a-5p will also promote the expression of osteogenic differentiation-related proteins ALP, RUNX-2, OPN, and Col-2.

In order to investigate the unilateral buckling behavior of rectangular plates with different elastic rotational restraint stiffnesses on the rigid foundation, the buckling of rectangular plates with elastic rotation constraints on the rigid foundation under linear pressure and uniform shear force is studied. According to the buckling deformation under different loading conditions, the appropriate deflection surface function is proposed, and the theoretical solution to critical buckling load is deduced from the energy variation of plate buckling by using the Rayleigh-Ritz method. The buckling formula of the thin plate at the combined bending-shear stress is obtained by using the correlation stability checking formula. A finite element model is established to analyze the influence of different base stiffnesses and bending-shear ratios on the bending shear composite buckling stress. The results are compared with the web buckling test result of a semi filled steel box concrete composite beam in the negative moment region. The results show that the rigid foundation of semi filled concrete can be simplified as an elastic foundation with a stiffness coefficient slightly lower than 5.

Objective To investigate the expression of PD-1 and PD-L1/2 in T cell subsets and myeloma cells in the bone marrow from newly diagnosed multiple myeloma (NDMM) patients and their relation with clinical features. Methods We collected the bone marrow and clinical data of 22 NDMM patients and 18 cases of healthy controls. We sorted CD4+T cells, CD8+T cells and myeloma cells by flow cytometry, and observed the expression of PD-1 and PD-L1/2. Results Compared with the control group, the proportion of CD8+T cells in the NDMM group was significantly higher, while the ratio of CD4+/CD8+ was significantly lower (both P < 0.05). The expression levels of PD-1 and PD-L2 in CD4+T cells in the NDMM group were significantly higher than those in the control group (both P < 0.05). The expression levels of PD-1, PD-L1 and PD-L2 in T cell subsets and myeloma cells of NDMM patients were not correlated with the gender, age, immune typing, Durie-Salmon stage and subtypes, ISS stage or mSMART3.0 stratification (both P > 0.05). Conclusion Most of MM patients suffering immune abnormality, which may be associated with the mutual immunosuppressive effects between T lymphocytes and plasma cells which expressing PD-1 and PD-L1/2.

In this work, an innovative hybrid resistance spot-laser welding process, which first conducts resistance spot welding of aluminum and steel dissimilar materials, followed by laser spot welding, is proposed to join aluminum to steel. Through innovative designing of the electrode structure, the welding current distribution and the weld structure were optimized to produce a thin and uniform intermetallic layer with its thickness below 1.2 μm. Furthermore, the faying interface morphology of aluminum and steel dissimilar materials was changed from a traditional flat surface to an interface with a deep bulge into the aluminum weld. It was found that resistance spot weld had a considerable tensile-shear load but poor ductility and energy absorption due to the presence of a weak bonding area around the periphery of the joint, where facilitated the crack initiation and rapid propagation. The following laser spot welding process was conducted in the weak bonding area of the resistance spot welding joint, which inhibited rapid propagation of the cracks along the faying interface avoiding the interface fracture. Compared with resistance spot welding joints, the tensile-shear peak load and energy absorption were increased by 18.2 % and 424.8 % for hybrid welding joints, respectively.

Vasculogenic mimicry (VM) is different from classical tumor angiogenesis and does not depend on endothelial cells. VM is closely related to the prognosis of various cancers. Canstatin was first identified as an endogenous angiogenesis inhibitor. In the present study, the inhibitory effect of canstatin on VM formation was evaluated. Human glioblastoma cell lines U87 and U251 were letivirally transduced to overexpress canstatin gene or GFP as control. In vitro assays showed that canstatin overexpression reduced the tube formation of U87 and U251 cells in Matrigel. A xenograft glioma model was created by subcutaneous injection of lentivirally modified U87 cells into nude mice. The results of in vivo experiments showed that canstatin gene introduction inhibited the growth of glioma xenografts. In tumor xenografts overexpressing canstatin, U87-mediated formation of VM-like structures and VM-related VEGF (vascular endothelial growth factor) expression were remarkably reduced. Canstatin overexpression also decreased the phosphorylation of Akt and reduced the expression of Survivin in vitro. In addition, HIF-1α production and MMP-2 secretion were decreased by canstatin overexpression. Therefore, these results suggested a protective role of canstatin during VM-like structure formation of glioma probably via inhibiting signaling pathways inducing vasculogenic mimicry.

Precision medicine aims at tailored disease prevention and treatment strategies based on individualized exposure, including biological status, environment and lifestyle, etc. Common chronic non-communicable diseases involve a complex interplay of both genetic and environmental factors, while most of their etiologies remain unknown. With advances in multi-omics, population-based studies can contribute to the practice of precision medicine in control of chronic diseases by providing research evidence. Results from population-based studies can be beneficial to reveal etiology and pathogenesis from a population level, assist in more detailed phenotype classification, optimize disease risk prediction by better identifying high risk populations and improve targeted diagnosis, treatments, prevention and control strategies for different individuals, and ultimately promote public health standard.

Abstract Background A few reports have shown that unilateral transverse process-pedicle percutaneous kyphoplasty is a good choice for patients with osteoporotic vertebral compression fracture (OVCF). However, this issue remains controversial and the related comprehensive research was lacked. Methods A retrospective study was conducted on patients receiving PKP surgery for OVCF. Patients were divided into three groups according to surgical approach. Symptom and radiographical evaluation were performed preoperatively, 1-month postoperatively, 1-year postoperatively and follow-ups. And follow-ups were repeated every year. Visual Analogue Scale Score (VAS), Oswestry Disability Index (ODI) scores, anterior vertebral height, coronal Cobb angle and sagittal Cobb angle was determined and compared among three groups. Results Totally 447 patients were included with an average age of 76.6 ± 7.2 years old. UTP showed significantly shorter surgical duration (p

Objective To compare DEGs between primary and metastatic lesions in lung adenocarcinoma patients with positive ALK fusion gene, and to explore the mechanism of drug-resistance and the potential drug targets in metastatic lesions of lung adenocarcinoma patients. Methods GSE125864 was obtained from GEO database. According to the different sampling sites of tumor tissue, two groups were divided: primary tumor lesions group and metastatic tumor lesions group. The DEGs between the two groups were compared, and the differences in biological functions and enrichment signaling pathways of these DEGs were analyzed. The protein-protein interaction network was constructed and applied to screen hub genes. Based on TCGA and cancer treatment response portal database, the prognosis and drug target prediction of the 10 key cores were analyzed. Results In total, 227 DEGs were identified, with 134 upregulated DEGs and 93 downregulated DEGs in the metastatic tumor lesions group, compared with primary tumor lesions group. GO and KEGG enrichment analyses showed that the functions of these DEGs were mainly involved in complement and coagulation cascade, chemical carcinogenesis and retinol metabolism pathways. The top 10 hub genes with the highest degree were analyzed in the protein-protein interaction network. The expression of HRG and AHSG genes were associated with poor prognosis of lung adenocarcinoma patients, and SERPINC1, HRG, ApoA1, FGA and FGG genes were correlated with a variety of potential small molecule drugs. Conclusion The molecular functions and signaling pathways involved in DEGs may induce drug-resistance in metastatic ALK-positive lung adenocarcinoma patients.

Numerical simulation can establish corresponding models for temperature field, molten pool shape, residential stress, microstructure evolution in the metal SLM process effectively. Meanwhile this model can accurately predict the performance of forming parts, and provide scientific basis for process parameters optimization, consequently boost the metal SLM to industry application. In this paper, the latest research progress of numerical simulation in the process of metal laser additive manufacturing was summarized, including temperature field, molten pool dynamics, residual stress and deformation in the forming part, and microstructure change.The latest progress of numerical simulation in metal SLM process was summarized, and the metal SLM process was analyzed. Finally, the future development trend was put forward that metal SLM process numerical simulation should be combined with big data, artificial intelligence, deep learning and other technologies and numerical simulation accuracy will be further improved,the processing window of metal laser additive manufacturing will be broadened,and guidance will be provided for the development of individual products.

To protect image information security, we propose an encryption algorithm based on chaotic sequences and bits' cross-diffusion. First, two chaotic sequences are generated by two-dimensional logic-sine coupling mapping, and the original image is scrambled with the two sequences. Secondly, the scrambled image is transformed into a one-dimensional sequence, and the low-order bits between every two pixels are fused to change the detailed information of the image, improved the ability to resist differential attacks. Finally, chaotic sequences are generated by iterative logical mapping to perform pixel replacement and ciphertext diffusion. The known plaintext attack can be effectively resisted because of the stochastic combination of diffusion scheme and chaotic sequence. It also has a significant effect on resisting differential attack. Take Lena image as an example, NPCR and UACI can reach 99.6063% and 33.4477%, respectively, which are very close to the ideal value. The encryption scheme has good key sensitivity and strong ability to resist statistical attacks, which shows that the algorithm has adequate security.

Graphene is an advanced carbon functional material with inherent unique properties that make it suitable for a wide range of applications. It can be synthesized through either the top–down approach involving delamination of graphitic materials or the bottom–up approach involving graphene assembly from smaller building units. Common top–down approaches are exfoliation and reduction while bottom–up approaches include chemical vapour deposition, epitaxial growth, and pyrolysis. A range of materials have been successfully used as precursors in various synthesis methods to derive graphene. This review analyses and discusses the suitability of conventional, plant- and animal-derived, chemical, and fossil precursors for graphene synthesis. Together with its associated technical feasibility and economic and environmental impacts, the quality of resultant graphene is critically assessed and discussed. After evaluating the parameters mentioned above, the most appropriate synthesis method for each precursor is identified. While graphite is currently the most common precursor for graphene synthesis, several other precursors have the potential to synthesize graphene of comparable, if not better, quality and yield. Thus, this review provides an overview and insights into identifying the potential of various carbon precursors for large-scale and commercial production of fit-for-purpose graphene for specific applications.

The purpose of this article is to use theoretical analysis to determine the cause of an artificial frozen wall not closing. Due to the influence of the energy difference received by each freezing apparatus, groundwater flow, freezing hole spacing and other factors, their heat transfer with the surrounding soil layer has limited efficiency. Theoretical calculations and engineering examples are compared to verify the validity of the theoretical model. According to the longitudinal temperature measurement of the temperature measuring hole and the freezing apparatus, the whole field monitoring theory based on grey correlation method is proposed. Through the calculation of the hole-to-hole correlation degree to evaluate and predict the working effect of each freezing apparatus, it is determined that the freezing pipes No. 7~9 and No. 18~22 are the weak parts of the freezing wall. Therefore, the grey correlation analysis was compared and analyzed in the case of the "window" accident of the frozen wall of the shaft, which verified the practicability of the theory.

In recent years, more and more people are applying Convolutional Neural Networks to the study of sound signals. The main reason is the translational invariance of convolution in time and space. Thereby the diversity of the sound signal can be overcome. However, in terms of sound direction recognition, there are also problems such as a microphone matrix being too large, and feature selection. This paper proposes a sound direction recognition using a simulated human head with microphones at both ears. Theoretically, the two microphones cannot distinguish the front and rear directions. However, we use the original data of the two channels as the input of the convolutional neural network, and the resolution effect can reach more than 0.9. For comparison, we also chose the delay feature (GCC) for sound direction recognition. Finally, we also conducted experiments that used probability distributions to identify more directions.

Objective To investigate the clinical efficacy of single-clamp endoscopic 8-shaped suture for closure of iatrogenic perforation in the upper digestive tract following endoscopic full-thickness resection (EFTR). Methods We retrospectively analyzed the data of 38 patients with upper gastrointestinal submucosal tumors (SMT) with a diameter greater than 2 cm, which originated from the deep muscularis of the muscularis propria with bidirectional growth and were confirmed by preoperative abdominal CT and endoscopic ultrasonography in the Digestive Endoscopy Center of our hospital between November, 2018 and July, 2019. All these patients underwent EFTR of tumor, which resulted in iatrogenic perforation in the upper digestive tract. Single-clamp endoscopic 8-shaped suture was used to close the perforation, and the intra- and postoperative complications and postoperative follow-up data were analyzed to assess the feasibility, safety and efficacy of the approach. Results The patients had an average tumor diameter of 2.6±0.8 cm and a mean wound diameter of 3.8±0.5 cm. The perforation was successfully repaired in all the 38 cases with a mean suture time of 12.6±1.8 min. Six (15.8%) of the patients complained of abdominal pain and bloating after the operation, and 4 (10.5%) patients had fever postoperatively, which was transient in 3 cases and as a result of infection due to failure of suture disconnection in the other case. None of the patients had serious intraoperative and postoperative complications or conversion to open surgery during the operation. The postoperative hospital stay was 5-9 d, and the endoscopic wounds healed well at 1 month after the operation in all the cases with visible scar formation. Follow-up endoscopy at 3 months postoperatively revealed good wound healing without signs of tumor recurrence. Conclusion Single-clamp endoscopic 8-shaped suture can effectively repair iatrogenic perforation after EFTR, which has good safety and less invasiveness with a low cost and a low risk of conversion to open surgery.