As a highly invasive malignancy,esophageal cancer(EC)is a global health issue,and was the eighth most prevalent cancer and the sixth leading cause of cancerrelated death worldwide in 2020.Due to its highly immunogenic...As a highly invasive malignancy,esophageal cancer(EC)is a global health issue,and was the eighth most prevalent cancer and the sixth leading cause of cancerrelated death worldwide in 2020.Due to its highly immunogenic nature,emerging immunotherapy approaches,such as immune checkpoint blockade,have demonstrated promising efficacy in treating EC;however,certain limitations and challenges still exist.In addition,tumors may exhibit primary or acquired resistance to immunotherapy in the tumor immune microenvironment(TIME);thus,understanding the TIME is urgent and crucial,especially given the importance of an immunosuppressive microenvironment in tumor progression.The aim of this review was to better elucidate the mechanisms of the suppressive TIME,including cell infiltration,immune cell subsets,cytokines and signaling pathways in the tumor microenvironment of EC patients,as well as the downregulated expression of major histocompatibility complex molecules in tumor cells,to obtain a better understanding of the differences in EC patient responses to immunotherapeutic strategies and accurately predict the efficacy of immunotherapies.Therefore,personalized treatments could be developed to maximize the advantages of immunotherapy.展开更多
Two catalysts, nano-sized cobalt-metal-organic framework(Co-MOF) and nickel(Ni)-MOF, were successfully prepared by the modification method. Tetralin(C10H12) was used as the hydrogen donor for the catalytic cracking an...Two catalysts, nano-sized cobalt-metal-organic framework(Co-MOF) and nickel(Ni)-MOF, were successfully prepared by the modification method. Tetralin(C10H12) was used as the hydrogen donor for the catalytic cracking and hydrogenation modification study of the dehydrated crude oil from the Shengli Oilfield. The optimal reaction conditions were determined through orthogonal experiments, and the components of the crude oil and modified oil samples were analyzed. The results revealed that the nanoMOF catalysts were successfully prepared and exhibited high catalytic activity. They could catalyze the cracking of large molecules in heavy oil at mild temperatures(<300°C), leading to the decomposition of the hydrogen donor. When the mass fraction of the catalyst was 0.2%, the mass fraction of the hydrogen donor was 1%, and the reaction temperature was 280°C, the Ni-MOF showed the best catalytic viscosity reduction effect. It could reduce the viscosity of heavy oil at 50°C from 15761.9 m Pa.s to 1266.2 m Pa.s,with a viscosity reduction rate of 91.97%. The modification effect of Co-MOF was the next best, which could reduce the viscosity of heavy oil to 2500.1 m Pa.s with a viscosity reduction rate of 84.14%. Molecular dynamics simulations revealed a strong interaction force between the MOF surface and asphaltene molecules. In the process of heavy-oil catalytic hydrogenation, the nano-MOF catalyst exhibited high catalytic activity. On the one hand, the empty d orbitals outside the metal atoms in the catalyst could polarize the carbon atoms in the organic matter, accelerating the breaking of long chains. On the other hand, the metal atoms in the catalyst could bond with the carbon σ bonds, breaking the carbon-carbon bonds. This disrupted the structure of the recombined components in the crude oil, irreversibly reducing the viscosity of the heavy oil and improving its fluidity.展开更多
As an unconventional resource, oil shale possesses abundant reserves and significant potential for industrial applications. The rational and efficient development of oil shale resources holds immense importance in red...As an unconventional resource, oil shale possesses abundant reserves and significant potential for industrial applications. The rational and efficient development of oil shale resources holds immense importance in reducing national energy demand. In-situ catalytic technology, characterized by its high efficiency, low pollution, and minimal energy consumption, represents a key direction for future oil shale development. This paper provides a comprehensive review of research progress in in-situ oil shale mining technology, oil shale pyrolysis catalysts, the pyrolysis mechanism of kerogen, and the compatibility of different heating processes and catalysts. Furthermore, the paper proposes future research directions and prospects for oil shale in-situ catalytic technology, including reservoir modification, highefficiency catalyst synthesis, injection processes, and high-efficiency heating technology. These insights serve as valuable technical references for the advancement of oil shale in-situ catalytic technology.展开更多
The influences of rolling reduction and aluminum sheet initial thickness(AIT)on the thickness fluctuation of aluminum layer(TFA)of embedded aluminum?steel composite sheet produced by cold roll bonding were investigate...The influences of rolling reduction and aluminum sheet initial thickness(AIT)on the thickness fluctuation of aluminum layer(TFA)of embedded aluminum?steel composite sheet produced by cold roll bonding were investigated,the formation mechanism of TFA was analyzed and method to improve the thickness uniformity of the aluminum layer was proposed.The results showed that when the reduction increased,TFA increased gradually.When the reduction was lower than40%,AIT had negligible effect on the TFA,while TFA increased with the decrease of AIT when the reduction was higher than40%.The non-uniformities of the steel surface deformation and the interfacial bonding extent caused by the work-hardened steel surface layer,were the main reasons for the formation of TFA.Adopting an appropriate surface treatment can help to decrease the hardening extent of the steel surface for improving the deformation uniformity during cold roll bonding process,which effectively improved the aluminum thickness uniformity of the embedded aluminum/steel composite sheets.展开更多
Objective:To investigate the expression characteristics of TNF-αin myocardium and hepatic tissue of rats with compound stress of hyperthermia and lipopoiysaccharide(LPS).Methods: Male SPF Wistar rats were randomly di...Objective:To investigate the expression characteristics of TNF-αin myocardium and hepatic tissue of rats with compound stress of hyperthermia and lipopoiysaccharide(LPS).Methods: Male SPF Wistar rats were randomly divided into room temperature+physiological saline group (Croup C),hyperthermia+physiological saline group(Croup II),room temperature+LPS group(Croup L) and hyperthermia+LPS group(Croup HL).The rats were put in simulated climate cabin.Croup HL and Croup H were exposed in the environment at a dry bulb temperature(TDB) of(35.0±0.5)℃,while Croup L and Croup C were exposed in the environment at a TDB of(26.0±0.5)℃. The rats in Croup HL and Croup L were given tail intravenous injection of LPS 10 mg/kg,while the rats in Croup H and Croup C were given tail intravenous injection of 9 g/L NaCl 10 ml/kg. After the stress,immunohistochemical SABC staining method was used to detect the expression characteristics of TNF-αin myocardium and hepatic tissue of rats,and those rats were given routine pathological examinations.Results:The expression of TNF-αin myocardium and hepatic tissue in Croup HL was enhanced remarkably,and the tissue damages of Croup HL were severest.Conclusions:The eardiotoxieity and hepatotoxicity caused by compound stress of hyperthermia and LPS is closely related to the expression of TNF-α.展开更多
Copper matrix composites reinforced by in situ-formed hybrid titanium boride whiskers(TiB_(w))and titanium diboride particles(TiB_(2p))were fabricated by powder metallurgy.Microstructural observations showed competiti...Copper matrix composites reinforced by in situ-formed hybrid titanium boride whiskers(TiB_(w))and titanium diboride particles(TiB_(2p))were fabricated by powder metallurgy.Microstructural observations showed competitive precipitation behavior between TiB_(w) and TiB_(2p),where the relative contents of the two reinforcements varied with sintering temperature.Based on thermodynamic and kinetic assessments,the precipitation mechanisms of the hybrid reinforcements were discussed,and the formation of both TiB_(w) and TiB_(2p) from the local melting zone was thermodynamically favored.The precipitation kinetics were mainly controlled by a solid-state diffusion of B atoms.By forming a compact compound layer,in situ reactions were divided into two stages,where Zener growth and Dybkov growth prevailed,respectively.Accordingly,the competitive precipitation behavior was attributed to the transition of the growth model during the reaction process.展开更多
AIM: To investigate proteomic changes in spinal cord and dorsal root ganglia (DRG) of rats with trinitrobenzene sulfonic acid (TNBS)-induced colitis. METHODS: The colonic myeloperoxidase (MPO) activity and tumor necro...AIM: To investigate proteomic changes in spinal cord and dorsal root ganglia (DRG) of rats with trinitrobenzene sulfonic acid (TNBS)-induced colitis. METHODS: The colonic myeloperoxidase (MPO) activity and tumor necrosis factor-(TNF- ) level were determined. A two-dimensional electrophoresis (2-DE)-based proteomic technique was used to profile the global protein expression changes in the DRG and spinal cord of the rats with acute colitis induced by intracolonic injection of TNBS. RESULTS: TNBS group showed significantly elevated colonic MPO activity and increased TNF-level. The proteins derived from lumbosacral enlargement of the spinal cord and DRG were resolved by 2-DE; and 26 and 19 proteins that displayed significantly different expression levels in the DRG and spinal cord were identified respectively. Altered proteins were found to be involved in a number of biological functions, such as inflammation/immunity, cell signaling, redox regulation, sulfate transport and cellular metabolism. The over-expression of the protein similar to potassium channel tetramerisation domain containing protein 12 (Kctd 12) and low expression of proteasome subunit type-1 (psma) were validated by Western blotting analysis. CONCLUSION: TNBS-induced colitis has a profound impact on protein profiling in the nervous system. This result helps understand the neurological pathogenesis of inflammatory bowel disease.展开更多
Generally, a magnetic target can be described with six parameters, three describing the position and three describing the magnetic moment. Due to a lack of sufficient components from one magnetometer, we need more tha...Generally, a magnetic target can be described with six parameters, three describing the position and three describing the magnetic moment. Due to a lack of sufficient components from one magnetometer, we need more than one magnetometer when locating the magnetic target. Thus, a magnetometer array should be designed. The baseline of the array is an important factor that affects the localization accuracy of the target. In this paper, we focus on the localization of a static target by using a scalar magnetometer array. We present the scalar magnetometer array with a cross-shaped structure.We propose a method of determining the optimal baseline according to the parameters of the magnetometer and detection requirements. In the method, we use the traditional signal-to-noise ratio（SNR） as a performance index, and obtain the optimal baseline of the array by using the Monte Carlo method. The proposed method of determining the optimal baseline is verified in simulation. The arrays with different baselines are used to locate a static magnetic target. The results show that the location performance is better when using the array with the optimal baseline determined by the proposed method.展开更多
AIM To ascertain the prognostic role of the T4 and N2 category in stage Ⅲ pancreatic cancer according to the 8 th edition of the American Joint Committee on Cancer(AJCC) classification.METHODS Patients were collected...AIM To ascertain the prognostic role of the T4 and N2 category in stage Ⅲ pancreatic cancer according to the 8 th edition of the American Joint Committee on Cancer(AJCC) classification.METHODS Patients were collected from the Surveillance Epidemiology and End Results(SEER) database(2004-2013) and were divided into three groups: T(1-3)N2, T4 N(0-1), and T4 N2. Overall survival(OS) and disease-specific survival(DSS) of patients were evaluated by the Kaplan-Meier method. RESULTS For the first time, we found a significant difference in OS and DSS between T(1-3)N2/T4 N(0-1) and T4 N2 butnot between T(1-3)N2 and T4 N(0-1). A higher grading correlated with a worse prognosis in the T(1-3)N2 and T4 N2 groups.CONCLUSION Patients with stage T4 N2 had a worse prognosis than those with stage T(1-3)N2/T4 N(0-1) in the 8 th edition AJCC staging system for pancreatic cancer. We recommend that stage Ⅲ should be subclassified into stage ⅢA [T(1-3)N2/T4 N(0-1)] and stage ⅢB(T4 N2).展开更多
BACKGROUND Single atrium with single ventricle,or a two-chambered heart,is an extremely rare congenital malformation.Few cases with two-chambered heart surviving to adulthood have been reported.CASE SUMMARY We reporte...BACKGROUND Single atrium with single ventricle,or a two-chambered heart,is an extremely rare congenital malformation.Few cases with two-chambered heart surviving to adulthood have been reported.CASE SUMMARY We reported an adult female patient with a two-chambered heart and situs inversus totalis accompanied by multiple pregnancies and abortions.Magnetic resonance imaging detected a two-chambered heart.B-ultrasound-guided uterine aspiration was performed to absorb 8 g and 10 g of organized villus and decidual tissues,respectively,with a small amount of bleeding.Postoperatively,cyanosis and fatigue-induced shortness of breath were gradually relieved.The patient has currently outlived all similar cases reported so far.CONCLUSION Hemodynamic changes in pregnant women with two-chambered heart impaired cardiac function,responsible for hypoperfusion and miscarriage.展开更多
To measure the parameters of fiber and to visualize the reshaping process of fiber in air tunnel,an experimental approach is developed in the present work.The tunnel is designed with gradient flow velocity,and the fib...To measure the parameters of fiber and to visualize the reshaping process of fiber in air tunnel,an experimental approach is developed in the present work.The tunnel is designed with gradient flow velocity,and the fiber reshaping images as well as the fiber length value are obtained experimentally.An analytical expression of velocity distribution in the tunnel is theoretically derived and the simulated results are obtained.Automatic fiber reshaping including stretch and rotation is verified using the dynamical equation and the multi-spherical chain model.It is shown that pull force by air flow makes a chain of balls become straight and Stokes moment makes the ball chain rotate.Finally,reshaping criterion related with flow velocity is formulated.展开更多
The ^1 S0 nucleonic superfluids are investigated within the relativistic meanfield model and Bardeen-Cooper-Schrieffer theory in hyperonic neutron stars. The ^1 S0 pairing gaps of neutrons and protons are calculated b...The ^1 S0 nucleonic superfluids are investigated within the relativistic meanfield model and Bardeen-Cooper-Schrieffer theory in hyperonic neutron stars. The ^1 S0 pairing gaps of neutrons and protons are calculated based on the Reid soft-core interaction as the nucleon-nucleon interaction. In particular, we have studied the influence of degrees of freedom for hyperons on the ^1 S0 nucleonic pairing gap in neutron star matter. It is found that the appearance of hyperons has little impact on the baryonic density range and the size of the ^1S0 neutronic pairing gap; the ^1S0 protonic pairing gap also decreases slightly in this region where ρB = 0.0-0.393 fm^-3. However, if baryonic density becomes greater than 0.393 fm^-3, the ^1S0 protonic pairing gap obviously increases. In addition, the possible range for a protonic superfluid is obviously enlarged due to the presence of hyperons. In our results, the hyperons change the 1 So protonic pairing gap, which must change the cooling properties of neutron stars.展开更多
Objective To observe the effect of Astragalus polysaccharides（APS） on cardiac function and expression of Keap1/Nrf2-ARE signal pathway in adjuvant arthritis（AA） rats. Methods Forty-eight rats were randomly divided...Objective To observe the effect of Astragalus polysaccharides（APS） on cardiac function and expression of Keap1/Nrf2-ARE signal pathway in adjuvant arthritis（AA） rats. Methods Forty-eight rats were randomly divided into normal control（NC） group, model control（MC） group, leflunomide（LEF） group, and APS group. The AA model rats were induced with Freund＇s complete adjuvant, then administration began from day 19 after modeling for 30 d. The paw swelling and arthritic index（AI）, the cardiac function indexes, the expression of Keap1, maf, Nrf2 m RNAs, and HO-1, r-GCS proteins in cardiac tissues were observed. Oxidation-related substances（SOD, MDA, ROS, and TAC） and cytokines（IL-10 and TNF-ɑ） were also determined. Results Compared with NC group, the paw swelling and AI were increased, and the body weight was decreased in MC group. HR, HI, LVSP, LVEDP, and levels of MDA, TAC, ROS, RNS, and TNF-ɑ in MC group were increased, while dp/dtmax and levels of GSH, TRX, and IL-10 were decreased. Compared with MC group, LEF group showed higher HR and ± dp/dtmax, and lower LVEDP. In APS group, the HR, LVSP, and LVEDP were decreased and ±dp/dtmax was increased. TNF-ɑ was decreased, TAC, ROS, MDA, and IL-10 were increased in both LEF and APS groups. APS and LEF groups also showed less MDA, TAC, ROS, and SOD, and the differences were statistically significant. Spearman correlation analysis showed that the cardiac function parameters were positively correlated with Keap1, anti-oxidant indicators, and anti-inflammation cytokines, and negatively correlated with Nrf2, oxidation indictors, pro-inflammation cytokines, and inflammation indictors.Conclusion APS can adjust the expression of Keap1/Nrf2-ARE signal pathway in AA rats, and can also improve their cardiac function. The mechanism may be involved in increasing myocardial anti-oxidant capacity, reducing oxidative stress, and inhibiting inflammation.展开更多
Electrical pole-changing technology leads to torque ripple and speed fluctuation despite broadening the constant power speed range of the multiphase induction machine （IM） system. To reduce the torque ripple and spe...Electrical pole-changing technology leads to torque ripple and speed fluctuation despite broadening the constant power speed range of the multiphase induction machine （IM） system. To reduce the torque ripple and speed fluctuation of the machine, we investigate an exponential response electrical pole-changing method for five-phase IM with a current sliding-mode control strategy. This control strategy employs the dual-plane （dr-q1 and d2-q2） vector control method, which allows the IM to operate under different pole modes. Current sliding-mode controllers are applied instead of conventional proportional integral （PI） controllers to adjust the current vectors, and exponential current response achieves a smooth transition between the d1-q1 and d2-q2 planes. Compared with the step response pole-changing with PI control method, the proposed pole-changing method greatly reduces the torque ripple and speed fluctuation of the IM during the pole-changing process. Experimental results verify the ex- ceptional performance of the proposed electrical pole-changing strategy.展开更多
Dense hydroxyapatite （HA） ceramic is a promising material for hard tissue repair due to its unique physical properties and biologic properties. However, the brittleness and low compressive strength of traditional HA...Dense hydroxyapatite （HA） ceramic is a promising material for hard tissue repair due to its unique physical properties and biologic properties. However, the brittleness and low compressive strength of traditional HA ceramics limited their applications, because previous sintering methods produced HA ceramics with crystal sizes greater than nanometer range. In this study, nano-sized HA powder was employed to fabricate dense nanocrystal HA ceramic by high pressure molding, and followed by a three-step sintering process. The phase composition, microstructure, crystal dimension and crystal shape of the sintered ceramic were examined by X-ray diffraction （XRD） and scanning electron microscopy （SEM）. Mechanical properties of the HA ceramic were tested, and cytocompatibility was evaluated. The phase of the sintered ceramic was pure HA, and the crystal size was about 200 nm. The compressive strength and elastic modulus of the HA ceramic were comparable to human cortical bone, especially the good fatigue strength overcame brittleness of traditional sintered HA ceramics. Cell attachment experiment also demonstrated that the ceramics had a good cytocompatibility.展开更多
Objective：To compare the brain pharmacokinetics of five protoberberine-type alkaloids（i.e.berberine,palmatine,coptisine,epiberberine,and jatrorrhizine）,which were the main bioactive constituents of Jiaotai Pills（...Objective：To compare the brain pharmacokinetics of five protoberberine-type alkaloids（i.e.berberine,palmatine,coptisine,epiberberine,and jatrorrhizine）,which were the main bioactive constituents of Jiaotai Pills（JTP）,in normal and insomnic rats orally administrated with JTP.Methods：The detection was conducted by a fully validated liquid chromatography-tandem mass spectrometry combinated with brain microdialysis method.Brain microdialysis probes were inserted into the hippocampus of rats.JTP extracts were administrated intragastrically and then brain microdialysates were collected at 30 min time intervals for 10 h.The separation of the five protoberberine-type alkaloids was carried out on a BDS Hypersilusing a mobile phase consisting of acetonitrile and water（containing 5 mmol ammonium acetate adjusted to p H 5.0）within 4 min.The quantification was performed by multiple reaction monitoring with the transitions of m/z 336.0-320.1 for berberine,m/z 352.0-336.1for palmatine,m/z 338.0-322.1 for jatrorrhizine,m/z 336.0-320.1 for epiberberine,m/z 320.0-292.1 for coptisine and m/z 356.4-192.1 for IS.Results：The lower limit of quantification for five protoberberine-type alkaloids was 0.05 ng/m L.Linearity,accuracy,precision,stability and matrix effect of five analytes were all satisfactory.Five protoberberinetype alkaloids were quickly distributed in the brain.Moreover,significant differences in the principal pharmacokinetic parameters such as AUC andthe analytes were observed between two groups.Conclusion：The LC-MS/MS method combinated with microdialysis is useful in the brain pharmacokinetic study of five protoberberine-type alkaloids.The results indicated that the rates of analytes absorption in insomnic rats were significantly higher than those in normal rats.Besides,the protoberberine-type alkaloids could bring a direct effect on the neuron in the hippocampus.展开更多
基金Supported by Xi’an Municipal Health Commission of China,No.2022qn07 and No.2023ms11.
文摘As a highly invasive malignancy,esophageal cancer(EC)is a global health issue,and was the eighth most prevalent cancer and the sixth leading cause of cancerrelated death worldwide in 2020.Due to its highly immunogenic nature,emerging immunotherapy approaches,such as immune checkpoint blockade,have demonstrated promising efficacy in treating EC;however,certain limitations and challenges still exist.In addition,tumors may exhibit primary or acquired resistance to immunotherapy in the tumor immune microenvironment(TIME);thus,understanding the TIME is urgent and crucial,especially given the importance of an immunosuppressive microenvironment in tumor progression.The aim of this review was to better elucidate the mechanisms of the suppressive TIME,including cell infiltration,immune cell subsets,cytokines and signaling pathways in the tumor microenvironment of EC patients,as well as the downregulated expression of major histocompatibility complex molecules in tumor cells,to obtain a better understanding of the differences in EC patient responses to immunotherapeutic strategies and accurately predict the efficacy of immunotherapies.Therefore,personalized treatments could be developed to maximize the advantages of immunotherapy.
基金financially supported by the National Natural Science Foundation of China(52174047)Sinopec Project(P21063-3).
文摘Two catalysts, nano-sized cobalt-metal-organic framework(Co-MOF) and nickel(Ni)-MOF, were successfully prepared by the modification method. Tetralin(C10H12) was used as the hydrogen donor for the catalytic cracking and hydrogenation modification study of the dehydrated crude oil from the Shengli Oilfield. The optimal reaction conditions were determined through orthogonal experiments, and the components of the crude oil and modified oil samples were analyzed. The results revealed that the nanoMOF catalysts were successfully prepared and exhibited high catalytic activity. They could catalyze the cracking of large molecules in heavy oil at mild temperatures(<300°C), leading to the decomposition of the hydrogen donor. When the mass fraction of the catalyst was 0.2%, the mass fraction of the hydrogen donor was 1%, and the reaction temperature was 280°C, the Ni-MOF showed the best catalytic viscosity reduction effect. It could reduce the viscosity of heavy oil at 50°C from 15761.9 m Pa.s to 1266.2 m Pa.s,with a viscosity reduction rate of 91.97%. The modification effect of Co-MOF was the next best, which could reduce the viscosity of heavy oil to 2500.1 m Pa.s with a viscosity reduction rate of 84.14%. Molecular dynamics simulations revealed a strong interaction force between the MOF surface and asphaltene molecules. In the process of heavy-oil catalytic hydrogenation, the nano-MOF catalyst exhibited high catalytic activity. On the one hand, the empty d orbitals outside the metal atoms in the catalyst could polarize the carbon atoms in the organic matter, accelerating the breaking of long chains. On the other hand, the metal atoms in the catalyst could bond with the carbon σ bonds, breaking the carbon-carbon bonds. This disrupted the structure of the recombined components in the crude oil, irreversibly reducing the viscosity of the heavy oil and improving its fluidity.
基金financially supported by the National Natural Science Foundation of China(52174047)Sinopec Project(P21063-3)。
文摘As an unconventional resource, oil shale possesses abundant reserves and significant potential for industrial applications. The rational and efficient development of oil shale resources holds immense importance in reducing national energy demand. In-situ catalytic technology, characterized by its high efficiency, low pollution, and minimal energy consumption, represents a key direction for future oil shale development. This paper provides a comprehensive review of research progress in in-situ oil shale mining technology, oil shale pyrolysis catalysts, the pyrolysis mechanism of kerogen, and the compatibility of different heating processes and catalysts. Furthermore, the paper proposes future research directions and prospects for oil shale in-situ catalytic technology, including reservoir modification, highefficiency catalyst synthesis, injection processes, and high-efficiency heating technology. These insights serve as valuable technical references for the advancement of oil shale in-situ catalytic technology.
基金Project(2013AA031301)supported by National High-tech Research and Development Program of ChinaProject(51104016)supported by National Natural Science Foundation of ChinaProject(BM2014006)supported by Jiangsu Key Laboratory for Clad Materials,China
文摘The influences of rolling reduction and aluminum sheet initial thickness(AIT)on the thickness fluctuation of aluminum layer(TFA)of embedded aluminum?steel composite sheet produced by cold roll bonding were investigated,the formation mechanism of TFA was analyzed and method to improve the thickness uniformity of the aluminum layer was proposed.The results showed that when the reduction increased,TFA increased gradually.When the reduction was lower than40%,AIT had negligible effect on the TFA,while TFA increased with the decrease of AIT when the reduction was higher than40%.The non-uniformities of the steel surface deformation and the interfacial bonding extent caused by the work-hardened steel surface layer,were the main reasons for the formation of TFA.Adopting an appropriate surface treatment can help to decrease the hardening extent of the steel surface for improving the deformation uniformity during cold roll bonding process,which effectively improved the aluminum thickness uniformity of the embedded aluminum/steel composite sheets.
文摘Objective:To investigate the expression characteristics of TNF-αin myocardium and hepatic tissue of rats with compound stress of hyperthermia and lipopoiysaccharide(LPS).Methods: Male SPF Wistar rats were randomly divided into room temperature+physiological saline group (Croup C),hyperthermia+physiological saline group(Croup II),room temperature+LPS group(Croup L) and hyperthermia+LPS group(Croup HL).The rats were put in simulated climate cabin.Croup HL and Croup H were exposed in the environment at a dry bulb temperature(TDB) of(35.0±0.5)℃,while Croup L and Croup C were exposed in the environment at a TDB of(26.0±0.5)℃. The rats in Croup HL and Croup L were given tail intravenous injection of LPS 10 mg/kg,while the rats in Croup H and Croup C were given tail intravenous injection of 9 g/L NaCl 10 ml/kg. After the stress,immunohistochemical SABC staining method was used to detect the expression characteristics of TNF-αin myocardium and hepatic tissue of rats,and those rats were given routine pathological examinations.Results:The expression of TNF-αin myocardium and hepatic tissue in Croup HL was enhanced remarkably,and the tissue damages of Croup HL were severest.Conclusions:The eardiotoxieity and hepatotoxicity caused by compound stress of hyperthermia and LPS is closely related to the expression of TNF-α.
基金This work was financially supported by the National Natural Science Foundation of China(Nos.U1502274,51834009,and 51974244).
文摘Copper matrix composites reinforced by in situ-formed hybrid titanium boride whiskers(TiB_(w))and titanium diboride particles(TiB_(2p))were fabricated by powder metallurgy.Microstructural observations showed competitive precipitation behavior between TiB_(w) and TiB_(2p),where the relative contents of the two reinforcements varied with sintering temperature.Based on thermodynamic and kinetic assessments,the precipitation mechanisms of the hybrid reinforcements were discussed,and the formation of both TiB_(w) and TiB_(2p) from the local melting zone was thermodynamically favored.The precipitation kinetics were mainly controlled by a solid-state diffusion of B atoms.By forming a compact compound layer,in situ reactions were divided into two stages,where Zener growth and Dybkov growth prevailed,respectively.Accordingly,the competitive precipitation behavior was attributed to the transition of the growth model during the reaction process.
基金Supported by The Research Grants Council of Hong Kong,RGC-HKBU2/07CThe Hong Kong Jockey Club Institute of Chinese Medicine, JCICM4-07
文摘AIM: To investigate proteomic changes in spinal cord and dorsal root ganglia (DRG) of rats with trinitrobenzene sulfonic acid (TNBS)-induced colitis. METHODS: The colonic myeloperoxidase (MPO) activity and tumor necrosis factor-(TNF- ) level were determined. A two-dimensional electrophoresis (2-DE)-based proteomic technique was used to profile the global protein expression changes in the DRG and spinal cord of the rats with acute colitis induced by intracolonic injection of TNBS. RESULTS: TNBS group showed significantly elevated colonic MPO activity and increased TNF-level. The proteins derived from lumbosacral enlargement of the spinal cord and DRG were resolved by 2-DE; and 26 and 19 proteins that displayed significantly different expression levels in the DRG and spinal cord were identified respectively. Altered proteins were found to be involved in a number of biological functions, such as inflammation/immunity, cell signaling, redox regulation, sulfate transport and cellular metabolism. The over-expression of the protein similar to potassium channel tetramerisation domain containing protein 12 (Kctd 12) and low expression of proteasome subunit type-1 (psma) were validated by Western blotting analysis. CONCLUSION: TNBS-induced colitis has a profound impact on protein profiling in the nervous system. This result helps understand the neurological pathogenesis of inflammatory bowel disease.
基金supported by the National Natural Science Foundation of China(Grant No.61174192)
文摘Generally, a magnetic target can be described with six parameters, three describing the position and three describing the magnetic moment. Due to a lack of sufficient components from one magnetometer, we need more than one magnetometer when locating the magnetic target. Thus, a magnetometer array should be designed. The baseline of the array is an important factor that affects the localization accuracy of the target. In this paper, we focus on the localization of a static target by using a scalar magnetometer array. We present the scalar magnetometer array with a cross-shaped structure.We propose a method of determining the optimal baseline according to the parameters of the magnetometer and detection requirements. In the method, we use the traditional signal-to-noise ratio（SNR） as a performance index, and obtain the optimal baseline of the array by using the Monte Carlo method. The proposed method of determining the optimal baseline is verified in simulation. The arrays with different baselines are used to locate a static magnetic target. The results show that the location performance is better when using the array with the optimal baseline determined by the proposed method.
文摘AIM To ascertain the prognostic role of the T4 and N2 category in stage Ⅲ pancreatic cancer according to the 8 th edition of the American Joint Committee on Cancer(AJCC) classification.METHODS Patients were collected from the Surveillance Epidemiology and End Results(SEER) database(2004-2013) and were divided into three groups: T(1-3)N2, T4 N(0-1), and T4 N2. Overall survival(OS) and disease-specific survival(DSS) of patients were evaluated by the Kaplan-Meier method. RESULTS For the first time, we found a significant difference in OS and DSS between T(1-3)N2/T4 N(0-1) and T4 N2 butnot between T(1-3)N2 and T4 N(0-1). A higher grading correlated with a worse prognosis in the T(1-3)N2 and T4 N2 groups.CONCLUSION Patients with stage T4 N2 had a worse prognosis than those with stage T(1-3)N2/T4 N(0-1) in the 8 th edition AJCC staging system for pancreatic cancer. We recommend that stage Ⅲ should be subclassified into stage ⅢA [T(1-3)N2/T4 N(0-1)] and stage ⅢB(T4 N2).
基金Supported by Chinese Ministry of Education(No.2020-39)Zunyi Science and Technology Project,No.Zunshi Kehe HZ(2020)246.
文摘BACKGROUND Single atrium with single ventricle,or a two-chambered heart,is an extremely rare congenital malformation.Few cases with two-chambered heart surviving to adulthood have been reported.CASE SUMMARY We reported an adult female patient with a two-chambered heart and situs inversus totalis accompanied by multiple pregnancies and abortions.Magnetic resonance imaging detected a two-chambered heart.B-ultrasound-guided uterine aspiration was performed to absorb 8 g and 10 g of organized villus and decidual tissues,respectively,with a small amount of bleeding.Postoperatively,cyanosis and fatigue-induced shortness of breath were gradually relieved.The patient has currently outlived all similar cases reported so far.CONCLUSION Hemodynamic changes in pregnant women with two-chambered heart impaired cardiac function,responsible for hypoperfusion and miscarriage.
基金Supported by the National Natural Science Foundation of China under Grant Nos.51605009 and 51975011。
文摘To measure the parameters of fiber and to visualize the reshaping process of fiber in air tunnel,an experimental approach is developed in the present work.The tunnel is designed with gradient flow velocity,and the fiber reshaping images as well as the fiber length value are obtained experimentally.An analytical expression of velocity distribution in the tunnel is theoretically derived and the simulated results are obtained.Automatic fiber reshaping including stretch and rotation is verified using the dynamical equation and the multi-spherical chain model.It is shown that pull force by air flow makes a chain of balls become straight and Stokes moment makes the ball chain rotate.Finally,reshaping criterion related with flow velocity is formulated.
基金Supported by the National Natural Science Foundation of China
文摘The ^1 S0 nucleonic superfluids are investigated within the relativistic meanfield model and Bardeen-Cooper-Schrieffer theory in hyperonic neutron stars. The ^1 S0 pairing gaps of neutrons and protons are calculated based on the Reid soft-core interaction as the nucleon-nucleon interaction. In particular, we have studied the influence of degrees of freedom for hyperons on the ^1 S0 nucleonic pairing gap in neutron star matter. It is found that the appearance of hyperons has little impact on the baryonic density range and the size of the ^1S0 neutronic pairing gap; the ^1S0 protonic pairing gap also decreases slightly in this region where ρB = 0.0-0.393 fm^-3. However, if baryonic density becomes greater than 0.393 fm^-3, the ^1S0 protonic pairing gap obviously increases. In addition, the possible range for a protonic superfluid is obviously enlarged due to the presence of hyperons. In our results, the hyperons change the 1 So protonic pairing gap, which must change the cooling properties of neutron stars.
基金Key Projects in the National Science and Technology Pillar Program in the Twelfth Five-Year Plan Period(No.2012BAI26B02)National Key Disciplines of Chinese Medicine Construction Projects(No.[2009]30)
文摘Objective To observe the effect of Astragalus polysaccharides（APS） on cardiac function and expression of Keap1/Nrf2-ARE signal pathway in adjuvant arthritis（AA） rats. Methods Forty-eight rats were randomly divided into normal control（NC） group, model control（MC） group, leflunomide（LEF） group, and APS group. The AA model rats were induced with Freund＇s complete adjuvant, then administration began from day 19 after modeling for 30 d. The paw swelling and arthritic index（AI）, the cardiac function indexes, the expression of Keap1, maf, Nrf2 m RNAs, and HO-1, r-GCS proteins in cardiac tissues were observed. Oxidation-related substances（SOD, MDA, ROS, and TAC） and cytokines（IL-10 and TNF-ɑ） were also determined. Results Compared with NC group, the paw swelling and AI were increased, and the body weight was decreased in MC group. HR, HI, LVSP, LVEDP, and levels of MDA, TAC, ROS, RNS, and TNF-ɑ in MC group were increased, while dp/dtmax and levels of GSH, TRX, and IL-10 were decreased. Compared with MC group, LEF group showed higher HR and ± dp/dtmax, and lower LVEDP. In APS group, the HR, LVSP, and LVEDP were decreased and ±dp/dtmax was increased. TNF-ɑ was decreased, TAC, ROS, MDA, and IL-10 were increased in both LEF and APS groups. APS and LEF groups also showed less MDA, TAC, ROS, and SOD, and the differences were statistically significant. Spearman correlation analysis showed that the cardiac function parameters were positively correlated with Keap1, anti-oxidant indicators, and anti-inflammation cytokines, and negatively correlated with Nrf2, oxidation indictors, pro-inflammation cytokines, and inflammation indictors.Conclusion APS can adjust the expression of Keap1/Nrf2-ARE signal pathway in AA rats, and can also improve their cardiac function. The mechanism may be involved in increasing myocardial anti-oxidant capacity, reducing oxidative stress, and inhibiting inflammation.
基金Project supported by the National Basic Research Program(973)of China(No.2013CB035600)
文摘Electrical pole-changing technology leads to torque ripple and speed fluctuation despite broadening the constant power speed range of the multiphase induction machine （IM） system. To reduce the torque ripple and speed fluctuation of the machine, we investigate an exponential response electrical pole-changing method for five-phase IM with a current sliding-mode control strategy. This control strategy employs the dual-plane （dr-q1 and d2-q2） vector control method, which allows the IM to operate under different pole modes. Current sliding-mode controllers are applied instead of conventional proportional integral （PI） controllers to adjust the current vectors, and exponential current response achieves a smooth transition between the d1-q1 and d2-q2 planes. Compared with the step response pole-changing with PI control method, the proposed pole-changing method greatly reduces the torque ripple and speed fluctuation of the IM during the pole-changing process. Experimental results verify the ex- ceptional performance of the proposed electrical pole-changing strategy.
文摘Dense hydroxyapatite （HA） ceramic is a promising material for hard tissue repair due to its unique physical properties and biologic properties. However, the brittleness and low compressive strength of traditional HA ceramics limited their applications, because previous sintering methods produced HA ceramics with crystal sizes greater than nanometer range. In this study, nano-sized HA powder was employed to fabricate dense nanocrystal HA ceramic by high pressure molding, and followed by a three-step sintering process. The phase composition, microstructure, crystal dimension and crystal shape of the sintered ceramic were examined by X-ray diffraction （XRD） and scanning electron microscopy （SEM）. Mechanical properties of the HA ceramic were tested, and cytocompatibility was evaluated. The phase of the sintered ceramic was pure HA, and the crystal size was about 200 nm. The compressive strength and elastic modulus of the HA ceramic were comparable to human cortical bone, especially the good fatigue strength overcame brittleness of traditional sintered HA ceramics. Cell attachment experiment also demonstrated that the ceramics had a good cytocompatibility.
基金supported by the National Natural Science Foundation of China(No.81473319 and No.81473540)the Key Projects of Guangdong Natural Science Foundation(No.2017A030311022)+3 种基金the Guangdong Science and Technology Program(No.2015A030401031,2014A020209026)the Guangdong Natural Science Foundation(No.2015A030313123)the Zhongshan Science and Technology Program(No.2016C1015)the Science Program for Overseas Scholar of Guangzhou University of Chinese Medicine(Torch Program)(No.XH20170111)
文摘Objective：To compare the brain pharmacokinetics of five protoberberine-type alkaloids（i.e.berberine,palmatine,coptisine,epiberberine,and jatrorrhizine）,which were the main bioactive constituents of Jiaotai Pills（JTP）,in normal and insomnic rats orally administrated with JTP.Methods：The detection was conducted by a fully validated liquid chromatography-tandem mass spectrometry combinated with brain microdialysis method.Brain microdialysis probes were inserted into the hippocampus of rats.JTP extracts were administrated intragastrically and then brain microdialysates were collected at 30 min time intervals for 10 h.The separation of the five protoberberine-type alkaloids was carried out on a BDS Hypersilusing a mobile phase consisting of acetonitrile and water（containing 5 mmol ammonium acetate adjusted to p H 5.0）within 4 min.The quantification was performed by multiple reaction monitoring with the transitions of m/z 336.0-320.1 for berberine,m/z 352.0-336.1for palmatine,m/z 338.0-322.1 for jatrorrhizine,m/z 336.0-320.1 for epiberberine,m/z 320.0-292.1 for coptisine and m/z 356.4-192.1 for IS.Results：The lower limit of quantification for five protoberberine-type alkaloids was 0.05 ng/m L.Linearity,accuracy,precision,stability and matrix effect of five analytes were all satisfactory.Five protoberberinetype alkaloids were quickly distributed in the brain.Moreover,significant differences in the principal pharmacokinetic parameters such as AUC andthe analytes were observed between two groups.Conclusion：The LC-MS/MS method combinated with microdialysis is useful in the brain pharmacokinetic study of five protoberberine-type alkaloids.The results indicated that the rates of analytes absorption in insomnic rats were significantly higher than those in normal rats.Besides,the protoberberine-type alkaloids could bring a direct effect on the neuron in the hippocampus.
