The functional and structural integrity of the blood-brain barrier is crucial in maintaining homeostasis in the brain microenvironment;however,the molecular mechanisms underlying the formation and function of the bloo...The functional and structural integrity of the blood-brain barrier is crucial in maintaining homeostasis in the brain microenvironment;however,the molecular mechanisms underlying the formation and function of the blood-brain barrier remain poorly understood.The major facilitator superfamily domain containing 2A has been identified as a key regulator of blood-brain barrier function.It plays a critical role in promoting and maintaining the formation and functional stability of the blood-brain barrier,in addition to the transport of lipids,such as docosahexaenoic acid,across the blood-brain barrier.Furthermore,an increasing number of studies have suggested that major facilitator superfamily domain containing 2A is involved in the molecular mechanisms of blood-brain barrier dysfunction in a variety of neurological diseases;however,little is known regarding the mechanisms by which major facilitator superfamily domain containing 2A affects the blood-brain barrier.This paper provides a comprehensive and systematic review of the close relationship between major facilitator superfamily domain containing 2A proteins and the blood-brain barrier,including their basic structures and functions,cross-linking between major facilitator superfamily domain containing 2A and the blood-brain barrier,and the in-depth studies on lipid transport and the regulation of blood-brain barrier permeability.This comprehensive systematic review contributes to an in-depth understanding of the important role of major facilitator superfamily domain containing 2A proteins in maintaining the structure and function of the blood-brain barrier and the research progress to date.This will not only help to elucidate the pathogenesis of neurological diseases,improve the accuracy of laboratory diagnosis,and optimize clinical treatment strategies,but it may also play an important role in prognostic monitoring.In addition,the effects of major facilitator superfamily domain containing 2A on blood-brain barrier leakage in various diseases and the research progress on cross-blood-brain barrier drug delivery are summarized.This review may contribute to the development of new approaches for the treatment of neurological diseases.展开更多
BACKGROUND Hepatocellular carcinoma(HCC)is at the forefront of the global spectrum of cancer incidence and mortality,with conventional therapies like tyrosine kinase inhibitors limited by resistance.Recent studies hav...BACKGROUND Hepatocellular carcinoma(HCC)is at the forefront of the global spectrum of cancer incidence and mortality,with conventional therapies like tyrosine kinase inhibitors limited by resistance.Recent studies have highlighted the promising anticancer effects of nitidine chloride(NC)against HCC.SAC3 domain containing 1(SAC3D1)is critical for centrosome replication and spindle formation.However,research on SAC3D1 in HCC and NC remains limited.AIM To investigate the mechanisms underlying SAC3D1’s role in HCC progression and evaluated its potential as a therapeutic target of NC.METHODS RNA sequencing(RNA-seq)identified SAC3D1 expression changes in HCC cells after NC treatment.Molecular docking was further employed to validate the direct binding between NC and SAC3D1.Additionally,HCC multicenter data(The Cancer Genome Atlas_GTEx,ArrayExpress),pathway analysis,Pearson correlation analysis and SAC3D1 in vitro knockdown experiments were integrated to explore the molecular mechanisms underlying SAC3D1's involvement in HCC progression.RESULTS RNA-seq showed that NC treatment significantly downregulated SAC3D1 expression[log2(fold change)=-0.95,P<0.05],with molecular docking revealing that NC directly bound to SAC3D1 proteins(binding energy:-9.7 kcal/mol).Enrichment analysis showed that most pathways were closely related to the cell cycle.Pearson correlation analysis indicated that SAC3D1 and cell cycle genes were significantly positively correlated(correlation coefficient≥0.3,P<0.05).SAC3D1 knockdown inhibited HCC cell invasion,migration,and proliferation by arresting cells in the S and G2/M phases.Flow cytometry confirmed that after SAC3D1 knockdown,the early and total apoptosis percentage of HCC cells decreased,while the late apoptosis percentage increased.CONCLUSION As a potential target of NC,SAC3D1 may inhibit HCC progression through cell cycle regulation following its downregulation by NC.展开更多
BACKGROUND Metabolic dysregulation is considered a significant hallmark of hepatocellular carcinoma(HCC).SAC3 domain containing 1(SAC3D1)functions in the cell cycle,and its expression is upregulated in various cancers...BACKGROUND Metabolic dysregulation is considered a significant hallmark of hepatocellular carcinoma(HCC).SAC3 domain containing 1(SAC3D1)functions in the cell cycle,and its expression is upregulated in various cancers.It is known that metabolic changes occur at different stages of the cell cycle to maintain the biosynthesis and replication of both normal and cancer cells.Based on the role of SAC3D1 in mitosis,we hypothesize that abnormal expression of SAC3D1 may affect cellular metabolism.However,it remains unclear whether SAC3D1 mediates the progression of HCC by regulating metabolic reprogramming.AIM To comprehensively elucidate the impact and molecular mechanism of SAC3D1 on the progression of HCC by regulating the metabolic reprogramming.METHODS The constructed SAC3D1 overexpression and knockdown HCC cell lines were used for detecting cell proliferation,migration capabilities,as well as glycolysis and adenosine triphosphate(ATP)production rate assays.They were also employed for examining molecular markers associated with cell migration and glycolysis.The transcriptome sequencing data of cells have revealed the pathways potentially influenced by SAC3D1.The tail vein metastasis model and xenograft tumor experiments were utilized to demonstrate SAC3D1’s tumor-promoting effects in vivo.RESULTS SAC3D1 expression was upregulated and associated with poor prognosis in HCC patients.SAC3D1 enhanced the proliferation and migration abilities and reduced the population dependence of HCC cells in vitro and in vivo.The upregulation of SAC3D1 enhanced cellular glycolysis and ATP production.The cell transcriptome sequencing data revealed that SAC3D1 activated Wnt signaling pathway.SAC3D1 did not modulate the transcription ofβ-Catenin,while might inhibit its degradation.Further investigations indicated that the increase of SAC3D1 leads to moreβ-Catenin accumulating in the nucleus,facilitating the expression of c-Myc,one of the upstream regulatory factors of glycolysis.The iCRT3,an antagonist ofβ-Catenin,could counteract the increase of c-Myc induced by SAC3D1,while also downregulating the expression of glycolysis-related proteins.CONCLUSION This study found that SAC3D1 enhances HCC cell glycolysis and ATP production via theβ-Catenin/c-Myc signaling axis,thereby promoting the progression of HCC.展开更多
BACKGROUND The mortality rate for severe cases of acute pancreatitis(AP),a common gastrointestinal emergency,is as high as 30%.Our previous study has shown that rutaecarpine(Rut)has a therapeutic effect on AP.AIM To i...BACKGROUND The mortality rate for severe cases of acute pancreatitis(AP),a common gastrointestinal emergency,is as high as 30%.Our previous study has shown that rutaecarpine(Rut)has a therapeutic effect on AP.AIM To investigate the role of F-box and WD repeat domain containing 11(FBXW11)in AP models and to assess whether Rut mitigates AP by regulating FBXW11.METHODS AP rat model was established and treated with Rut,followed by biochemical analysis of serum amylase and lipase,hematoxylin and eosin staining of pancreatic tissue,and immunohistochemistry detection of pancreatic Ly6G,CD11b,and myeloperoxidase.Assay kits were used to detect oxidative stress-related indicators in pancreatic tissue and inflammatory factors in serum.AR42J cells were treated with cerulein to model AP and subjected to Cell Counting Kit-8 viability assay,flow cytometry apoptosis assay,and immunofluorescence detection of reactive oxygen species to elucidate the mechanistic involvement of the enhancer of zeste homolog 2(EZH2)-FBXW11 axis in Rut-mediated protection against AP.The EZH2-histone H3 binding and H3 methylation were evaluated using co-immunoprecipitation.RESULTS Rut treatment ameliorated AP severity,as evidenced by reduced serum levels of pancreatic enzymes(amylase and lipase)and attenuated histological damage.Rut also decreased inflammatory markers(interleukin-1 beta,interleukin-6,and tumor necrosis factor alpha),tissue oxidative stress(malondialdehyde),and neutrophil infiltration(Ly6G,CD11b,and myeloperoxidase)levels in rats with AP.Moreover,Rut restored pancreatic antioxidant capacity(glutathione and superoxide dismutase).In vitro,Rut pre-incubation enhanced cell viability and suppressed cerulein-induced apoptosis and oxidative stress.Rut increased EZH2 expression while decreasing FBXW11 expression.FBXW11 overexpression eliminated the protective effect of Rut against AP.Further analysis revealed that EZH2 binds to H3 and upregulates H3 methylation levels,thereby inhibiting FBXW11 expression.CONCLUSION Collectively,our findings demonstrate that Rut ameliorates AP by upregulating EZH2,thereby enhancing H3 methylation and suppressing FBXW11 expression.展开更多
BACKGROUND The role of NLR family pyrin domain containing 3(NLRP3)in post-endoscopic submucosal dissection(ESD)esophageal stricture remains incompletely understood.The effect of celastrol(CEL)on the prevention of esop...BACKGROUND The role of NLR family pyrin domain containing 3(NLRP3)in post-endoscopic submucosal dissection(ESD)esophageal stricture remains incompletely understood.The effect of celastrol(CEL)on the prevention of esophageal strictures has not yet been investigated.AIM To explore the effect of CEL on the prevention of esophageal stricture in rats.METHODS NLRP3,interleukin(IL)-1β,and IL-18 mRNA levels were measured in patients’tissues after esophageal ESD.NLRP3 expression in esophageal fibroblasts was determined using immunohistochemistry and immunofluorescence staining.Lentiviral transfection was used to induce NLRP3 overexpression and thioredoxin reductase 1(TXNRD1)silencing.The CCK8 assay was used to determine the optimal CEL concentration.Reactive oxygen species(ROS)generation was detected via fluorescence and flow cytometry.Masson’s trichrome staining and barium esophagography were performed to assess collagen deposition and esophageal stenosis.RESULTS The mRNA levels of NLRP3 and IL-1βwere higher in human tissues from the ESD resection bed than in normal esophageal mucosa.NLRP3 overexpression in primary rat esophageal fibroblasts led to high collagen 1 expression.Thus,NLRP3 participated in esophageal inflammation and tissue repair after ESD.Comparable to prednisolone,CEL significantly inhibited NLRP3 activation in vitro and in vivo,and esophageal strictures were markedly alleviated.Mechanistically,CEL upregulated TXNRD1 expression and reduced ROS production,thereby inhibiting NLRP3 expression.This effect was reversed by TXNRD1 silencing.Furthermore,TXNRD1 interacted with NLRP3 and promoted its ubiquitination.CONCLUSION CEL is a promising alternative therapeutic agent for the prevention of post-ESD esophageal strictures.展开更多
A mutant UW 3, which is unable to fix N 2 in the presence of Mo (Nif -) but undergo phenotypic reversal to Nif + under Mo deficiency, was able to grow in Mo- and NH 3-deficient medium containing Mn, and the growt...A mutant UW 3, which is unable to fix N 2 in the presence of Mo (Nif -) but undergo phenotypic reversal to Nif + under Mo deficiency, was able to grow in Mo- and NH 3-deficient medium containing Mn, and the growth was accelerated by Mn at low concentration. A partly purified nitrogenase component Ⅰ protein separated from UW 3 grown in the Mn-containing medium was shown to contain Fe and Mn atoms (ratio of Fe/Mo/Mn: 10.41/0.19/1.00) with C 2H 2- and H +-reducing activity which almost equal to half of that of MoFe protein purified from wild-type mutant of Azotobacter vinelandii Lipmann. This protein was obviously different from MoFe protein in both absorption spectrum and circular dichroism, and the molecular weight of subunits in Mn-containing protein was close to that of α subunit in MoFe protein. The preliminary results indicated that the protein containing Mn might be a nitrogenase component Ⅰ protein.展开更多
Carbon-bearing stratum normally features low resistance and high polarization.If the lithostratigraphy of the exploration area contains large amounts of carbon,the induced polarization anomaly caused by metal sulfide ...Carbon-bearing stratum normally features low resistance and high polarization.If the lithostratigraphy of the exploration area contains large amounts of carbon,the induced polarization anomaly caused by metal sulfide ore bodies will be inundated by the high polarization of carbon-containing wall rock.In this work,we adopted time-domain induced polarization(TDIP)and controlled-source audio-frequency magnetotellurics(CSAMT)on deep prospecting of the carbon-bearing stratum of the Ar Horqin Banner,Inner Mongolia.The underground medium is divided into target geologic bodies according to the geological information within the known exploration line borehole,and the physical properties of various target geologic bodies are calculated using weighted averages to build a geologic-geophysical model that can fit the observation data.Consequently,we can determine the range and morphological characteristics of the electrical properties of the ore-bearing geologic bodies in the inversion results in the study area.Then we can use the characteristics summarized from the known exploration line to interpret unknown exploration line.Results indicated that,when the diff erence in physical properties between the ore body and interference wall rock is not clear,the geologic body can be classifi ed via the paragenetic(associated)assemblage relations of the underground medium.Geological interpretation is guided by the comprehensive physical properties of ore-bearing geologic bodies to avoid interferences.展开更多
As a main charging form of BF （blast furnace）, pellets play an important role in blast furnace process. However, comparing with sinters, pellets have many disadvantages, such as reduction swelling, low softening and...As a main charging form of BF （blast furnace）, pellets play an important role in blast furnace process. However, comparing with sinters, pellets have many disadvantages, such as reduction swelling, low softening and melting temperature and so on. Therefore, the flux pellets have been applied in blast furnace widely, especially MgO containing pellets. The light burned magnesite is applied as MgO containing additive in pellet production. The char- acters of light burned magnesite are explored. Meanwhile, the effects of it on low-temperature metallurgical proper-ties are investigated such as low-temperature reduction degradation index （RDI）, compressive strength （CS） and the reduction swelling index （RSI）. The light burned magnesite calcined at 850 ℃ manifests better grindability, larger specific surface area, and higher hydration activity. It is found that the addition of light burned magnesite can im- prove low-temperature metallurgical properties （RDI, RSI） of the pellets. With the increase of light burned magne-site in pellets, the RSI and RDI decrease gradually; when the proportion of light burned magnesite does not exceed 2.0% in pellets, the CS decreases slightly, but it still surnasses 2689 N. which can still meet the demand of BF.展开更多
Silver-ceramics (Ag2MO2)(M=Co, Ni, or Cu) were prepared through thermal decompositionof coprecipitated oxalates. Pellets of these materials were annealed at 350℃ for different timeperiods up to 5 h. The effect of ann...Silver-ceramics (Ag2MO2)(M=Co, Ni, or Cu) were prepared through thermal decompositionof coprecipitated oxalates. Pellets of these materials were annealed at 350℃ for different timeperiods up to 5 h. The effect of annealing time on the transport properties was studied. IR andX-ray spectra were also studied.展开更多
Inclusion characteristic and microstructure steel were evaluated with scanning electron of rare earth （RE） elements containing microscopy with energy dispersive spec- troscopy （SEM-EDS）, element-mapping, optical m...Inclusion characteristic and microstructure steel were evaluated with scanning electron of rare earth （RE） elements containing microscopy with energy dispersive spec- troscopy （SEM-EDS）, element-mapping, optical microscopy （OM）, and automated feature analysis （AFA） option equipped with ASPEX PSEM. Factsage was used to calculate the equilibrium inclusion composition. Based on the calculation, an inclu- sion evolution mechanism was proposed. Furthermore, line scanning analysis was used to elucidate the intra-granular acicular ferrite （IAF） nucleation mechanism. The re- sult showed that two different inclusions exist in sample steel： （Mn-A1-Si-Ti-La-Ce-O） ＋MnS complex inclusion and isolated MnS inclusion. Almost all nucleation sites for IAF are complex inclusions, while single MnS inclusion cannot induce IAF. A possible formation mechanism of complex inclusion is proposed based on calculated results using Factsage, which agrees well with experimental results. A Mn-depletion zone （MDZ） which exists adjacent to the （Mn-A1-Si-Ti-La-Ce-O） ＋MnS complex inclusion can account for the IAF formation. However, the low volume fraction （1.49× 10-7） of effective inclusion may result in only 10% （volume fraction） IAF.展开更多
The effects of rare earth Ce on the microstructure and mechanical properties of impure copper containing Pb were investigated using OM,SEM,EPMA,TEM and tensile testing.TEM and EDS analysis reveal that spherical CePb3 ...The effects of rare earth Ce on the microstructure and mechanical properties of impure copper containing Pb were investigated using OM,SEM,EPMA,TEM and tensile testing.TEM and EDS analysis reveal that spherical CePb3 particles form after Ce addition.CePb3 particles,with average size of^3.6μm,homogenously distribute in the Cu matrix.Due to small lattice misfit(~4.62%)with Cu matrix,CePb3 particles can act as effective nucleation sites beneficial to the grain refinement.Pb at grain boundaries seriously deteriorates the mechanical properties of Cu.The tensile strength and the elongation of Cu-0.1 Pb are decreased by 43.1%and 56.7%compared with those of pure copper,respectively.Ce can purify grain boundaries,cause the precipitation of CePb3 particles and refine grain sizes,which contribute to significant improvement of the mechanical properties of Cu.Compared with Cu-0.1Pb,the tensile strength(179 MPa)and the elongation(38.5%)of Cu-0.1Pb-0.3Ce are increased by 117.6%and 151.6%,respectively.展开更多
Mechanical properties of quenching,intercritical quenching and tempering （QLT） treated steel containing Ni of 9% were evaluated from specimens subject to various tempering temperatures. The detailed microstructures ...Mechanical properties of quenching,intercritical quenching and tempering （QLT） treated steel containing Ni of 9% were evaluated from specimens subject to various tempering temperatures. The detailed microstructures of steel containing Ni of 9% at different tempering temperatures were observed by optical microscope （OM） and transmission electron microscope （TEM）. The volume fraction of austenite was estimated by XRD. The results show that high strength and cryogenic toughness of steel containing Ni of 9% are obtained when the tempering temperature are between 540 and 580 ℃. The microstructure keeps the dual phase lamellar structure after the intercritical quenching and there is cementite created in the Ni-rich constituents when tempering temperature is 540 ℃. When tempering temperatures are between 560 and 580 ℃,the reversed austenites （γ′） grow up and the dual phase lamellar structure is not clear. The γ′ becomes instable at 600 ℃. When tempered at temperature ranging from 500 to 520 ℃,the increase of dislocation density in the lamellar matrix makes both tensile strength and yield strength decrease. When tempered at 540 ℃ and higher temperature,the yield strength decreases continuously because the C and alloying elements in the matrix are absorbed by the cementite and the γ′,so the yield ratio is decreased by the γ′. There are two toughness mechanisms at different tempering temperatures. One is that the precipitation of cementite absorbs the carbon in the steel which plays a major role in improving cryogenic toughness at lower temperature. Another is that the γ′ and the purified matrix become major role at higher tempering temperature. When the tempering temperature is 600 ℃,the stability of γ′ is decreased quickly,even the transformation takes place at room temperature,which results in a sharp decrease of Charpy-V impact energy at 77 K. The tempering temperature range is enlarged by the special distribution of cementite and the lamellar structure.展开更多
Based on domestic-developed triaxial servo-controlled seepage equipment for thermal-hydrologicalmechanical coupling of coal containing methane,an experimental study was carried out to investigate mechanical property a...Based on domestic-developed triaxial servo-controlled seepage equipment for thermal-hydrologicalmechanical coupling of coal containing methane,an experimental study was carried out to investigate mechanical property and gas permeability of raw coal,under the situation of conventional triaxial compression and unloading confining pressure tests in different gas pressure conditions.Triaxial unloading confining pressure process was reducing confining pressure while increasing axial pressure.The research results show that,compared with the peak intensity of conventional triaxial loading,the ultimate strength of coal samples of triaxial unloading confining pressure was lower,deformation under loading was far less than unloading,dilation caused by unloading was more obvious than loading.The change trend of volumetric strain would embody change of gas permeability of coal,the permeability first reduced along with volumetric strain increase,and then raised with volume strain decrease,furthermore,the change trends of permeability of coal before and after destruction were different in the stage of decreasing volume strain due to the effect of gas pressure.When gas pressure was greater,the effective confining pressure was smaller,and the radial deformation produced by unloading was greater.When the unloading failed confining pressure difference was smaller,coal would be easier to get unstable failure.展开更多
Nitrobenzene-containing industrial wastewater was degraded in the presence of ozone coupled with H2O2 by high gravity technology. The effect of high gravity factor, H2O2 concentration, pH value, liquid flow-rate, and ...Nitrobenzene-containing industrial wastewater was degraded in the presence of ozone coupled with H2O2 by high gravity technology. The effect of high gravity factor, H2O2 concentration, pH value, liquid flow-rate, and reaction time on the efficiency for removal of nitrobenzene was investigated. The experimental results show that the high gravity technology enhances the ozone utilization efficiency with O3/H202 showing synergistic effect. The degradation efficiency in terms of the COD removal rate and nitrobenzene removal rate reached 45.8% and 50.4%, respectively, under the following reaction conditions, viz.： a high gravity factor of 66.54, a pH value of 9, a H2O2/O3 molar ratio of 1：1, a liquid flow rate of 140 L/h, an ozone concentration of 40 rag/L, a H2O2 multiple dosing mode of 6 mL/h, and a reaction time of 4 h. Compared with the performance of conventional stirred aeration mixers, the high gravity technology could increase the COD and nitrobenzene removal rate related with the nitrobenzene-containing wastewater by 22.9% and 23.3%, respectively.展开更多
Effects of RE and Al on the structure, impact toughness, hardness, and wear resistance of high chromium cast iron containing wolfram were investigated. The results show that without modification the volume fraction of...Effects of RE and Al on the structure, impact toughness, hardness, and wear resistance of high chromium cast iron containing wolfram were investigated. The results show that without modification the volume fraction of austenite is high and the carbide appears to be thick lath and the grain size is relatively large; proper modification using RE combined with Al can reduce volume fraction of residual austenite in the as-cast structure obviously, refine grain size of primary austenite notably, and make the morphology of carbide changing from thick lath to thin lath, rosette, and feather-like modification can also increase hardness, wear resistance and impact toughness of cast iron.展开更多
Chromium ore fines containing coal (COFCC) can be rapidly heated by microwave to conduct the voluminal reduction, which lays a foundation of getting sponge ferrochromium powders with a lower content of C. Under the co...Chromium ore fines containing coal (COFCC) can be rapidly heated by microwave to conduct the voluminal reduction, which lays a foundation of getting sponge ferrochromium powders with a lower content of C. Under the conditions of COFCC with n(O)-n(C) (molar ratio) as 1.00-0.84 and n(SiO2)-n(CaO) as 1.00-0.39, the samples were heated by 10 kW microwave power to reach the given temperatures and held for different times respectively. The results show that the low-C-Cr ferrochromium metal phase in the reduced materials forms before the high-C-Cr ferrochromium metal phase does. With increasing temperature the C content of ferrochromium metals is in a positive correlation with the content of Cr. The C content of ferrochromium metal in reduced materials is 0-10.07% with an average value of 4.68%. With the increase of holding time the Cr content in ferrochromium metals is in a negative correlation with the content of C, while the content of Fe changes in the contrary way. In the microwave field the kinetic conditions of carburization are closely related with the temperature of microwave heating, holding time and carbon fitting ratio.展开更多
In order to explain the mechanism for gas outburst, the process of evolving fractures in coal seams is described using system dynamics with variable boundaries. We discuss the failure modes of coal containing gas and ...In order to explain the mechanism for gas outburst, the process of evolving fractures in coal seams is described using system dynamics with variable boundaries. We discuss the failure modes of coal containing gas and then established the flow rules after failure. The condition under which states of deformation convert is presented and the manner in which these convert is proposed. In the end, the process of gas outbursts is explained in detail. It shows that a gas outburst is a process in which the boundaries of coal seams are variable because of coal failure. If the fractures are not connected or even closed owing to coal/rock stress, fractured zones will retain a certain level of carrying capacity because of the self-sealing gas pressure. When the accumulation of gas energy reaches its limit, coal seams will become unstable and gas outbursts take place.展开更多
To study the relationship of oxidative, antioxidative constituents and antioxidases in blood with chronic cholecystitis containing gallstone, levels of lipoperoxides (LPO), nitric oxide (NO), vitamin C(VC), vitamin E ...To study the relationship of oxidative, antioxidative constituents and antioxidases in blood with chronic cholecystitis containing gallstone, levels of lipoperoxides (LPO), nitric oxide (NO), vitamin C(VC), vitamin E (VE) and β carotene (β CAR) in plasma as well as level of LPO, activities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSH Px) in erythrocytes were investigated by spectrophotometric assay in 107 patients with this condition (PCg) and 100 healthy volunteers (HVs). Compared with HVs group, the average value of LPO and NO in plasma and that of LPO in erythrocytes of PCg group were significantly increased ( P <0.0001), while that of VC, VE and β CAR in plasma and the average activities of SOD, CAT and GSH Px in erythrocytes were significantly decreased ( P <0.0001). Linear regression and correlation analysis for 107 preoperative PCg showed that the value of LPO and NO in plasma and that of LPO in erythrocytes of PCg gradually increased ( P <0.0001), representing a significant linear positive correlation. The value of VC, VE and β CAR in plasma and that of SOD, CAT and GSH Px in erythrocytes of PCg gradually decreased ( P <0.0001), representing a significant linear negative correlation. Stepwise regression and correlation analysis for 107 preoperative PCg suggested that the closest correlation was observed between the course of disease and the value of NO and VC in plasma and that of SOD, GSH Px and LPO in erythrocytes, r =0.7306, F =32.1408, P <0.0001. Compared with the preoperative PCg group, the average value of LPO and NO in plasma and that of LPO in erythrocytes of the postoperative PCg group were significantly decreased ( P <0.0001). Furthermore, the average value of VC in plasma and that of SOD, CAT and GSH Px in erythrocytes of the postoperative PCg group were significantly increased ( P <0.0001), whereas no significant difference was found between their average value of VE and β CAR in plasma. These findings suggested that oxidative stress was an aggravating pathological condition in PCg group. Therefore, we recommend that in treating PCg, antioxidants such as VC, VE, β CAR should be given in order to alleviate their potential oxidative damages.展开更多
Based on nine necessary basic assumptions for THM coupling model,this research comprehensively applied the theories of elastic mechanics,seepage mechanics and heat transfer,and established a real three-field and two-w...Based on nine necessary basic assumptions for THM coupling model,this research comprehensively applied the theories of elastic mechanics,seepage mechanics and heat transfer,and established a real three-field and two-way coupled mathematical model to reveal the connections among seepage field,deformation field and temperature field within the system of methane-containing coal.In comparison between numerical and analytical solutions,the coupling modeling for THM of methane-containing coal was proved to be correct by model application in the physical simulation experiment of coal and gas outburst.The model established in this paper was the improvement of traditional seepage theory of methane-containing coal and fluid-solid coupled model theory,which can be widely used in prevention of coal and gas outburst as well as exploitation of coal bed methane.展开更多
With high performance liquid chromatography, the concentrations of α-endosulfan, DDE, parathion methyl, isoproturon, atrazine, carbaryl and carbofuran were determined in farmed raised fish Labeo rohita of two weight ...With high performance liquid chromatography, the concentrations of α-endosulfan, DDE, parathion methyl, isoproturon, atrazine, carbaryl and carbofuran were determined in farmed raised fish Labeo rohita of two weight groups. All these pesticide residues were detected in fish meat samples. All these pesticide residues except isoproturon were identified in soil sediments, whereas all these pesticide residues except isoproturon, carbaryl and DDE were also present in water samples. DDT, heptachlor, β-endosulfan, chlorpyrifos, dimethoate, captan, cypermethrin, chlorobromuron and chlorotoluron were absent in all samples of water, sediments and fish flesh. The pesticide residues levels were in order of parathion methyl 〉 DDE 〉 carbofuran 〉 atrazine 〉 α-endosulfan 〉 isoproturan 〉 carbaryl. The concentrations of pesticides were higher in fish weighing 800 -1 300 g than in those weighing 250 -750 g. The DDE was remained highest in sediments, while that was not detected in water samples. The pesticides （endosulfan, parathion methyl, atrazine and carbofuran） had crossed their MRL values （0.001 μg/g） in water samples.展开更多
基金supported by the National Natural Science Foundation of China,No.82104412(to TD)Shaanxi Provincial Key R&D Program,No.2023-YBSF-165(to TD)+1 种基金the Natural Science Foundation of Shaanxi Department of Science and Technology,No.2018JM7022(to FM)Shaanxi Provincial Key Industry Chain Project,No.2021ZDLSF04-11(to PW)。
文摘The functional and structural integrity of the blood-brain barrier is crucial in maintaining homeostasis in the brain microenvironment;however,the molecular mechanisms underlying the formation and function of the blood-brain barrier remain poorly understood.The major facilitator superfamily domain containing 2A has been identified as a key regulator of blood-brain barrier function.It plays a critical role in promoting and maintaining the formation and functional stability of the blood-brain barrier,in addition to the transport of lipids,such as docosahexaenoic acid,across the blood-brain barrier.Furthermore,an increasing number of studies have suggested that major facilitator superfamily domain containing 2A is involved in the molecular mechanisms of blood-brain barrier dysfunction in a variety of neurological diseases;however,little is known regarding the mechanisms by which major facilitator superfamily domain containing 2A affects the blood-brain barrier.This paper provides a comprehensive and systematic review of the close relationship between major facilitator superfamily domain containing 2A proteins and the blood-brain barrier,including their basic structures and functions,cross-linking between major facilitator superfamily domain containing 2A and the blood-brain barrier,and the in-depth studies on lipid transport and the regulation of blood-brain barrier permeability.This comprehensive systematic review contributes to an in-depth understanding of the important role of major facilitator superfamily domain containing 2A proteins in maintaining the structure and function of the blood-brain barrier and the research progress to date.This will not only help to elucidate the pathogenesis of neurological diseases,improve the accuracy of laboratory diagnosis,and optimize clinical treatment strategies,but it may also play an important role in prognostic monitoring.In addition,the effects of major facilitator superfamily domain containing 2A on blood-brain barrier leakage in various diseases and the research progress on cross-blood-brain barrier drug delivery are summarized.This review may contribute to the development of new approaches for the treatment of neurological diseases.
基金Supported by National Natural Science Foundation of China,No.82160762 and No.82460783Guangxi Medical University“Four New”Project,No.SX202403+2 种基金Innovation Project of Guangxi Graduate Education,No.JGY2023068Guangxi Higher Education Undergraduate Teaching Reform Project,No.2022JGA146China Undergraduate Innovation and Entrepreneurship Training Program,No.202310598045.
文摘BACKGROUND Hepatocellular carcinoma(HCC)is at the forefront of the global spectrum of cancer incidence and mortality,with conventional therapies like tyrosine kinase inhibitors limited by resistance.Recent studies have highlighted the promising anticancer effects of nitidine chloride(NC)against HCC.SAC3 domain containing 1(SAC3D1)is critical for centrosome replication and spindle formation.However,research on SAC3D1 in HCC and NC remains limited.AIM To investigate the mechanisms underlying SAC3D1’s role in HCC progression and evaluated its potential as a therapeutic target of NC.METHODS RNA sequencing(RNA-seq)identified SAC3D1 expression changes in HCC cells after NC treatment.Molecular docking was further employed to validate the direct binding between NC and SAC3D1.Additionally,HCC multicenter data(The Cancer Genome Atlas_GTEx,ArrayExpress),pathway analysis,Pearson correlation analysis and SAC3D1 in vitro knockdown experiments were integrated to explore the molecular mechanisms underlying SAC3D1's involvement in HCC progression.RESULTS RNA-seq showed that NC treatment significantly downregulated SAC3D1 expression[log2(fold change)=-0.95,P<0.05],with molecular docking revealing that NC directly bound to SAC3D1 proteins(binding energy:-9.7 kcal/mol).Enrichment analysis showed that most pathways were closely related to the cell cycle.Pearson correlation analysis indicated that SAC3D1 and cell cycle genes were significantly positively correlated(correlation coefficient≥0.3,P<0.05).SAC3D1 knockdown inhibited HCC cell invasion,migration,and proliferation by arresting cells in the S and G2/M phases.Flow cytometry confirmed that after SAC3D1 knockdown,the early and total apoptosis percentage of HCC cells decreased,while the late apoptosis percentage increased.CONCLUSION As a potential target of NC,SAC3D1 may inhibit HCC progression through cell cycle regulation following its downregulation by NC.
基金Supported by the Shanghai Yangpu District Science and Technology Commission,No.YPQ202303Shanghai Municipal Health Commission Clinical Research Special Project,No.202240122Shanghai Medical Innovation Research Special Project,No.22Y11908600.
文摘BACKGROUND Metabolic dysregulation is considered a significant hallmark of hepatocellular carcinoma(HCC).SAC3 domain containing 1(SAC3D1)functions in the cell cycle,and its expression is upregulated in various cancers.It is known that metabolic changes occur at different stages of the cell cycle to maintain the biosynthesis and replication of both normal and cancer cells.Based on the role of SAC3D1 in mitosis,we hypothesize that abnormal expression of SAC3D1 may affect cellular metabolism.However,it remains unclear whether SAC3D1 mediates the progression of HCC by regulating metabolic reprogramming.AIM To comprehensively elucidate the impact and molecular mechanism of SAC3D1 on the progression of HCC by regulating the metabolic reprogramming.METHODS The constructed SAC3D1 overexpression and knockdown HCC cell lines were used for detecting cell proliferation,migration capabilities,as well as glycolysis and adenosine triphosphate(ATP)production rate assays.They were also employed for examining molecular markers associated with cell migration and glycolysis.The transcriptome sequencing data of cells have revealed the pathways potentially influenced by SAC3D1.The tail vein metastasis model and xenograft tumor experiments were utilized to demonstrate SAC3D1’s tumor-promoting effects in vivo.RESULTS SAC3D1 expression was upregulated and associated with poor prognosis in HCC patients.SAC3D1 enhanced the proliferation and migration abilities and reduced the population dependence of HCC cells in vitro and in vivo.The upregulation of SAC3D1 enhanced cellular glycolysis and ATP production.The cell transcriptome sequencing data revealed that SAC3D1 activated Wnt signaling pathway.SAC3D1 did not modulate the transcription ofβ-Catenin,while might inhibit its degradation.Further investigations indicated that the increase of SAC3D1 leads to moreβ-Catenin accumulating in the nucleus,facilitating the expression of c-Myc,one of the upstream regulatory factors of glycolysis.The iCRT3,an antagonist ofβ-Catenin,could counteract the increase of c-Myc induced by SAC3D1,while also downregulating the expression of glycolysis-related proteins.CONCLUSION This study found that SAC3D1 enhances HCC cell glycolysis and ATP production via theβ-Catenin/c-Myc signaling axis,thereby promoting the progression of HCC.
基金Supported by Hunan Provincial Natural Science Foundation of China,No.2022JJ40836the Key Project of Research and Development Plan of Hunan Province,No.2023DK2002the Postdoctoral Fellowship Program of China Postdoctoral Science Foundation,No.GZC20242045.
文摘BACKGROUND The mortality rate for severe cases of acute pancreatitis(AP),a common gastrointestinal emergency,is as high as 30%.Our previous study has shown that rutaecarpine(Rut)has a therapeutic effect on AP.AIM To investigate the role of F-box and WD repeat domain containing 11(FBXW11)in AP models and to assess whether Rut mitigates AP by regulating FBXW11.METHODS AP rat model was established and treated with Rut,followed by biochemical analysis of serum amylase and lipase,hematoxylin and eosin staining of pancreatic tissue,and immunohistochemistry detection of pancreatic Ly6G,CD11b,and myeloperoxidase.Assay kits were used to detect oxidative stress-related indicators in pancreatic tissue and inflammatory factors in serum.AR42J cells were treated with cerulein to model AP and subjected to Cell Counting Kit-8 viability assay,flow cytometry apoptosis assay,and immunofluorescence detection of reactive oxygen species to elucidate the mechanistic involvement of the enhancer of zeste homolog 2(EZH2)-FBXW11 axis in Rut-mediated protection against AP.The EZH2-histone H3 binding and H3 methylation were evaluated using co-immunoprecipitation.RESULTS Rut treatment ameliorated AP severity,as evidenced by reduced serum levels of pancreatic enzymes(amylase and lipase)and attenuated histological damage.Rut also decreased inflammatory markers(interleukin-1 beta,interleukin-6,and tumor necrosis factor alpha),tissue oxidative stress(malondialdehyde),and neutrophil infiltration(Ly6G,CD11b,and myeloperoxidase)levels in rats with AP.Moreover,Rut restored pancreatic antioxidant capacity(glutathione and superoxide dismutase).In vitro,Rut pre-incubation enhanced cell viability and suppressed cerulein-induced apoptosis and oxidative stress.Rut increased EZH2 expression while decreasing FBXW11 expression.FBXW11 overexpression eliminated the protective effect of Rut against AP.Further analysis revealed that EZH2 binds to H3 and upregulates H3 methylation levels,thereby inhibiting FBXW11 expression.CONCLUSION Collectively,our findings demonstrate that Rut ameliorates AP by upregulating EZH2,thereby enhancing H3 methylation and suppressing FBXW11 expression.
基金Supported by National Natural Science Foundation of China,No.82002609.
文摘BACKGROUND The role of NLR family pyrin domain containing 3(NLRP3)in post-endoscopic submucosal dissection(ESD)esophageal stricture remains incompletely understood.The effect of celastrol(CEL)on the prevention of esophageal strictures has not yet been investigated.AIM To explore the effect of CEL on the prevention of esophageal stricture in rats.METHODS NLRP3,interleukin(IL)-1β,and IL-18 mRNA levels were measured in patients’tissues after esophageal ESD.NLRP3 expression in esophageal fibroblasts was determined using immunohistochemistry and immunofluorescence staining.Lentiviral transfection was used to induce NLRP3 overexpression and thioredoxin reductase 1(TXNRD1)silencing.The CCK8 assay was used to determine the optimal CEL concentration.Reactive oxygen species(ROS)generation was detected via fluorescence and flow cytometry.Masson’s trichrome staining and barium esophagography were performed to assess collagen deposition and esophageal stenosis.RESULTS The mRNA levels of NLRP3 and IL-1βwere higher in human tissues from the ESD resection bed than in normal esophageal mucosa.NLRP3 overexpression in primary rat esophageal fibroblasts led to high collagen 1 expression.Thus,NLRP3 participated in esophageal inflammation and tissue repair after ESD.Comparable to prednisolone,CEL significantly inhibited NLRP3 activation in vitro and in vivo,and esophageal strictures were markedly alleviated.Mechanistically,CEL upregulated TXNRD1 expression and reduced ROS production,thereby inhibiting NLRP3 expression.This effect was reversed by TXNRD1 silencing.Furthermore,TXNRD1 interacted with NLRP3 and promoted its ubiquitination.CONCLUSION CEL is a promising alternative therapeutic agent for the prevention of post-ESD esophageal strictures.
文摘A mutant UW 3, which is unable to fix N 2 in the presence of Mo (Nif -) but undergo phenotypic reversal to Nif + under Mo deficiency, was able to grow in Mo- and NH 3-deficient medium containing Mn, and the growth was accelerated by Mn at low concentration. A partly purified nitrogenase component Ⅰ protein separated from UW 3 grown in the Mn-containing medium was shown to contain Fe and Mn atoms (ratio of Fe/Mo/Mn: 10.41/0.19/1.00) with C 2H 2- and H +-reducing activity which almost equal to half of that of MoFe protein purified from wild-type mutant of Azotobacter vinelandii Lipmann. This protein was obviously different from MoFe protein in both absorption spectrum and circular dichroism, and the molecular weight of subunits in Mn-containing protein was close to that of α subunit in MoFe protein. The preliminary results indicated that the protein containing Mn might be a nitrogenase component Ⅰ protein.
基金The Research is funded by Comprehensive Intelligent Mapping System and Application of Geological Survey(DD20190415)Exploration and Development Tracking and Result Integration of Energy and Important Mineral Resources(DD20190457)Resource Assessment and Prediction for Main Tectonic Metallogenetic Domains in the World(DD20190459).
文摘Carbon-bearing stratum normally features low resistance and high polarization.If the lithostratigraphy of the exploration area contains large amounts of carbon,the induced polarization anomaly caused by metal sulfide ore bodies will be inundated by the high polarization of carbon-containing wall rock.In this work,we adopted time-domain induced polarization(TDIP)and controlled-source audio-frequency magnetotellurics(CSAMT)on deep prospecting of the carbon-bearing stratum of the Ar Horqin Banner,Inner Mongolia.The underground medium is divided into target geologic bodies according to the geological information within the known exploration line borehole,and the physical properties of various target geologic bodies are calculated using weighted averages to build a geologic-geophysical model that can fit the observation data.Consequently,we can determine the range and morphological characteristics of the electrical properties of the ore-bearing geologic bodies in the inversion results in the study area.Then we can use the characteristics summarized from the known exploration line to interpret unknown exploration line.Results indicated that,when the diff erence in physical properties between the ore body and interference wall rock is not clear,the geologic body can be classifi ed via the paragenetic(associated)assemblage relations of the underground medium.Geological interpretation is guided by the comprehensive physical properties of ore-bearing geologic bodies to avoid interferences.
基金Item Sponsored by National Natural Science Foundation of China ( 51074206 , 51074040 )
文摘As a main charging form of BF （blast furnace）, pellets play an important role in blast furnace process. However, comparing with sinters, pellets have many disadvantages, such as reduction swelling, low softening and melting temperature and so on. Therefore, the flux pellets have been applied in blast furnace widely, especially MgO containing pellets. The light burned magnesite is applied as MgO containing additive in pellet production. The char- acters of light burned magnesite are explored. Meanwhile, the effects of it on low-temperature metallurgical proper-ties are investigated such as low-temperature reduction degradation index （RDI）, compressive strength （CS） and the reduction swelling index （RSI）. The light burned magnesite calcined at 850 ℃ manifests better grindability, larger specific surface area, and higher hydration activity. It is found that the addition of light burned magnesite can im- prove low-temperature metallurgical properties （RDI, RSI） of the pellets. With the increase of light burned magne-site in pellets, the RSI and RDI decrease gradually; when the proportion of light burned magnesite does not exceed 2.0% in pellets, the CS decreases slightly, but it still surnasses 2689 N. which can still meet the demand of BF.
文摘Silver-ceramics (Ag2MO2)(M=Co, Ni, or Cu) were prepared through thermal decompositionof coprecipitated oxalates. Pellets of these materials were annealed at 350℃ for different timeperiods up to 5 h. The effect of annealing time on the transport properties was studied. IR andX-ray spectra were also studied.
基金supported by the National Natural Science Foundation of China(No.2010CB30806)
文摘Inclusion characteristic and microstructure steel were evaluated with scanning electron of rare earth （RE） elements containing microscopy with energy dispersive spec- troscopy （SEM-EDS）, element-mapping, optical microscopy （OM）, and automated feature analysis （AFA） option equipped with ASPEX PSEM. Factsage was used to calculate the equilibrium inclusion composition. Based on the calculation, an inclu- sion evolution mechanism was proposed. Furthermore, line scanning analysis was used to elucidate the intra-granular acicular ferrite （IAF） nucleation mechanism. The re- sult showed that two different inclusions exist in sample steel： （Mn-A1-Si-Ti-La-Ce-O） ＋MnS complex inclusion and isolated MnS inclusion. Almost all nucleation sites for IAF are complex inclusions, while single MnS inclusion cannot induce IAF. A possible formation mechanism of complex inclusion is proposed based on calculated results using Factsage, which agrees well with experimental results. A Mn-depletion zone （MDZ） which exists adjacent to the （Mn-A1-Si-Ti-La-Ce-O） ＋MnS complex inclusion can account for the IAF formation. However, the low volume fraction （1.49× 10-7） of effective inclusion may result in only 10% （volume fraction） IAF.
基金Projects(ZR2018MEE005,ZR2018MEE016)supported by the Natural Science Foundation of Shandong Province,ChinaProject(J18KA059)supported by the Higher Educational Science and Technology Program of Shandong Province,ChinaProject(HJ16B01)supported by the Doctoral Fund of Yantai University,China。
文摘The effects of rare earth Ce on the microstructure and mechanical properties of impure copper containing Pb were investigated using OM,SEM,EPMA,TEM and tensile testing.TEM and EDS analysis reveal that spherical CePb3 particles form after Ce addition.CePb3 particles,with average size of^3.6μm,homogenously distribute in the Cu matrix.Due to small lattice misfit(~4.62%)with Cu matrix,CePb3 particles can act as effective nucleation sites beneficial to the grain refinement.Pb at grain boundaries seriously deteriorates the mechanical properties of Cu.The tensile strength and the elongation of Cu-0.1 Pb are decreased by 43.1%and 56.7%compared with those of pure copper,respectively.Ce can purify grain boundaries,cause the precipitation of CePb3 particles and refine grain sizes,which contribute to significant improvement of the mechanical properties of Cu.Compared with Cu-0.1Pb,the tensile strength(179 MPa)and the elongation(38.5%)of Cu-0.1Pb-0.3Ce are increased by 117.6%and 151.6%,respectively.
基金Item Sponsored by National High Technology Research and Development Program of China (2007AA03Z506)
文摘Mechanical properties of quenching,intercritical quenching and tempering （QLT） treated steel containing Ni of 9% were evaluated from specimens subject to various tempering temperatures. The detailed microstructures of steel containing Ni of 9% at different tempering temperatures were observed by optical microscope （OM） and transmission electron microscope （TEM）. The volume fraction of austenite was estimated by XRD. The results show that high strength and cryogenic toughness of steel containing Ni of 9% are obtained when the tempering temperature are between 540 and 580 ℃. The microstructure keeps the dual phase lamellar structure after the intercritical quenching and there is cementite created in the Ni-rich constituents when tempering temperature is 540 ℃. When tempering temperatures are between 560 and 580 ℃,the reversed austenites （γ′） grow up and the dual phase lamellar structure is not clear. The γ′ becomes instable at 600 ℃. When tempered at temperature ranging from 500 to 520 ℃,the increase of dislocation density in the lamellar matrix makes both tensile strength and yield strength decrease. When tempered at 540 ℃ and higher temperature,the yield strength decreases continuously because the C and alloying elements in the matrix are absorbed by the cementite and the γ′,so the yield ratio is decreased by the γ′. There are two toughness mechanisms at different tempering temperatures. One is that the precipitation of cementite absorbs the carbon in the steel which plays a major role in improving cryogenic toughness at lower temperature. Another is that the γ′ and the purified matrix become major role at higher tempering temperature. When the tempering temperature is 600 ℃,the stability of γ′ is decreased quickly,even the transformation takes place at room temperature,which results in a sharp decrease of Charpy-V impact energy at 77 K. The tempering temperature range is enlarged by the special distribution of cementite and the lamellar structure.
基金financially supported by the National Basic Research Program of China(No.2011CB201203)the National Natural Science Foundation of China(Nos.51204217 and 51374256)+1 种基金the National Major Science and Technology Projects of China(Nos.2011ZX05034-004 and 2011ZX05040-001-005)the Scientific Research Foundation of State Key Laboratory of Coal Mine Disaster Dynamics and Control(No.2011DA105287-MS201212)
文摘Based on domestic-developed triaxial servo-controlled seepage equipment for thermal-hydrologicalmechanical coupling of coal containing methane,an experimental study was carried out to investigate mechanical property and gas permeability of raw coal,under the situation of conventional triaxial compression and unloading confining pressure tests in different gas pressure conditions.Triaxial unloading confining pressure process was reducing confining pressure while increasing axial pressure.The research results show that,compared with the peak intensity of conventional triaxial loading,the ultimate strength of coal samples of triaxial unloading confining pressure was lower,deformation under loading was far less than unloading,dilation caused by unloading was more obvious than loading.The change trend of volumetric strain would embody change of gas permeability of coal,the permeability first reduced along with volumetric strain increase,and then raised with volume strain decrease,furthermore,the change trends of permeability of coal before and after destruction were different in the stage of decreasing volume strain due to the effect of gas pressure.When gas pressure was greater,the effective confining pressure was smaller,and the radial deformation produced by unloading was greater.When the unloading failed confining pressure difference was smaller,coal would be easier to get unstable failure.
基金financially supported by the National Natural Science Foundation of China(21206153)Science and Technology Development Program Fund of Taiyuan City(120164053)
文摘Nitrobenzene-containing industrial wastewater was degraded in the presence of ozone coupled with H2O2 by high gravity technology. The effect of high gravity factor, H2O2 concentration, pH value, liquid flow-rate, and reaction time on the efficiency for removal of nitrobenzene was investigated. The experimental results show that the high gravity technology enhances the ozone utilization efficiency with O3/H202 showing synergistic effect. The degradation efficiency in terms of the COD removal rate and nitrobenzene removal rate reached 45.8% and 50.4%, respectively, under the following reaction conditions, viz.： a high gravity factor of 66.54, a pH value of 9, a H2O2/O3 molar ratio of 1：1, a liquid flow rate of 140 L/h, an ozone concentration of 40 rag/L, a H2O2 multiple dosing mode of 6 mL/h, and a reaction time of 4 h. Compared with the performance of conventional stirred aeration mixers, the high gravity technology could increase the COD and nitrobenzene removal rate related with the nitrobenzene-containing wastewater by 22.9% and 23.3%, respectively.
文摘Effects of RE and Al on the structure, impact toughness, hardness, and wear resistance of high chromium cast iron containing wolfram were investigated. The results show that without modification the volume fraction of austenite is high and the carbide appears to be thick lath and the grain size is relatively large; proper modification using RE combined with Al can reduce volume fraction of residual austenite in the as-cast structure obviously, refine grain size of primary austenite notably, and make the morphology of carbide changing from thick lath to thin lath, rosette, and feather-like modification can also increase hardness, wear resistance and impact toughness of cast iron.
基金Project(50474083) supported by the National Natural Science Foundation of ChinaProject supported by the Baoshan Iron & Steel Co. Ltd. of China
文摘Chromium ore fines containing coal (COFCC) can be rapidly heated by microwave to conduct the voluminal reduction, which lays a foundation of getting sponge ferrochromium powders with a lower content of C. Under the conditions of COFCC with n(O)-n(C) (molar ratio) as 1.00-0.84 and n(SiO2)-n(CaO) as 1.00-0.39, the samples were heated by 10 kW microwave power to reach the given temperatures and held for different times respectively. The results show that the low-C-Cr ferrochromium metal phase in the reduced materials forms before the high-C-Cr ferrochromium metal phase does. With increasing temperature the C content of ferrochromium metals is in a positive correlation with the content of Cr. The C content of ferrochromium metal in reduced materials is 0-10.07% with an average value of 4.68%. With the increase of holding time the Cr content in ferrochromium metals is in a negative correlation with the content of C, while the content of Fe changes in the contrary way. In the microwave field the kinetic conditions of carburization are closely related with the temperature of microwave heating, holding time and carbon fitting ratio.
基金financial support from the National Basic Research Program of China (No.2005CB221500)the National Natural Science Foundation of China (Nos.50534049,50674087 and 50974107)the Natural Science Foundation of Jiangsu Province (No.BK2007029)
文摘In order to explain the mechanism for gas outburst, the process of evolving fractures in coal seams is described using system dynamics with variable boundaries. We discuss the failure modes of coal containing gas and then established the flow rules after failure. The condition under which states of deformation convert is presented and the manner in which these convert is proposed. In the end, the process of gas outbursts is explained in detail. It shows that a gas outburst is a process in which the boundaries of coal seams are variable because of coal failure. If the fractures are not connected or even closed owing to coal/rock stress, fractured zones will retain a certain level of carrying capacity because of the self-sealing gas pressure. When the accumulation of gas energy reaches its limit, coal seams will become unstable and gas outbursts take place.
文摘To study the relationship of oxidative, antioxidative constituents and antioxidases in blood with chronic cholecystitis containing gallstone, levels of lipoperoxides (LPO), nitric oxide (NO), vitamin C(VC), vitamin E (VE) and β carotene (β CAR) in plasma as well as level of LPO, activities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSH Px) in erythrocytes were investigated by spectrophotometric assay in 107 patients with this condition (PCg) and 100 healthy volunteers (HVs). Compared with HVs group, the average value of LPO and NO in plasma and that of LPO in erythrocytes of PCg group were significantly increased ( P <0.0001), while that of VC, VE and β CAR in plasma and the average activities of SOD, CAT and GSH Px in erythrocytes were significantly decreased ( P <0.0001). Linear regression and correlation analysis for 107 preoperative PCg showed that the value of LPO and NO in plasma and that of LPO in erythrocytes of PCg gradually increased ( P <0.0001), representing a significant linear positive correlation. The value of VC, VE and β CAR in plasma and that of SOD, CAT and GSH Px in erythrocytes of PCg gradually decreased ( P <0.0001), representing a significant linear negative correlation. Stepwise regression and correlation analysis for 107 preoperative PCg suggested that the closest correlation was observed between the course of disease and the value of NO and VC in plasma and that of SOD, GSH Px and LPO in erythrocytes, r =0.7306, F =32.1408, P <0.0001. Compared with the preoperative PCg group, the average value of LPO and NO in plasma and that of LPO in erythrocytes of the postoperative PCg group were significantly decreased ( P <0.0001). Furthermore, the average value of VC in plasma and that of SOD, CAT and GSH Px in erythrocytes of the postoperative PCg group were significantly increased ( P <0.0001), whereas no significant difference was found between their average value of VE and β CAR in plasma. These findings suggested that oxidative stress was an aggravating pathological condition in PCg group. Therefore, we recommend that in treating PCg, antioxidants such as VC, VE, β CAR should be given in order to alleviate their potential oxidative damages.
基金supported in part by the State Key Basic Research Program of China(No.2011CB201203)the General Project of the National Natural Science Foundation of China(No.50974141)+1 种基金the Key Project of the National Natural Science Foundation of China(No.50534080)the Key Special Subjects National Science and Technology of China(No.2011ZX05034-004)
文摘Based on nine necessary basic assumptions for THM coupling model,this research comprehensively applied the theories of elastic mechanics,seepage mechanics and heat transfer,and established a real three-field and two-way coupled mathematical model to reveal the connections among seepage field,deformation field and temperature field within the system of methane-containing coal.In comparison between numerical and analytical solutions,the coupling modeling for THM of methane-containing coal was proved to be correct by model application in the physical simulation experiment of coal and gas outburst.The model established in this paper was the improvement of traditional seepage theory of methane-containing coal and fluid-solid coupled model theory,which can be widely used in prevention of coal and gas outburst as well as exploitation of coal bed methane.
文摘With high performance liquid chromatography, the concentrations of α-endosulfan, DDE, parathion methyl, isoproturon, atrazine, carbaryl and carbofuran were determined in farmed raised fish Labeo rohita of two weight groups. All these pesticide residues were detected in fish meat samples. All these pesticide residues except isoproturon were identified in soil sediments, whereas all these pesticide residues except isoproturon, carbaryl and DDE were also present in water samples. DDT, heptachlor, β-endosulfan, chlorpyrifos, dimethoate, captan, cypermethrin, chlorobromuron and chlorotoluron were absent in all samples of water, sediments and fish flesh. The pesticide residues levels were in order of parathion methyl 〉 DDE 〉 carbofuran 〉 atrazine 〉 α-endosulfan 〉 isoproturan 〉 carbaryl. The concentrations of pesticides were higher in fish weighing 800 -1 300 g than in those weighing 250 -750 g. The DDE was remained highest in sediments, while that was not detected in water samples. The pesticides （endosulfan, parathion methyl, atrazine and carbofuran） had crossed their MRL values （0.001 μg/g） in water samples.
