BACKGROUND Dopamine and cyclic adenosine monophosphate(cAMP)-regulated phosphop-rotein with an apparent Mr of 32000(DARPP-32)is a protein that is involved in regulating dopamine and cAMP signaling pathways in the brai...BACKGROUND Dopamine and cyclic adenosine monophosphate(cAMP)-regulated phosphop-rotein with an apparent Mr of 32000(DARPP-32)is a protein that is involved in regulating dopamine and cAMP signaling pathways in the brain.However,recent studies have shown that DARPP-32 is also expressed in other tissues,including colorectal cancer(CRC),where its function is not well understood.AIM To explore the effect of DARPP-32 on CRC progression.METHODS The expression levels of DARPP-32 were assessed in CRC tissues using both quantitative polymerase chain reaction and immunohistochemistry assays.The proliferative capacity of CRC cell lines was evaluated with Cell Counting Kit-8 and 5-ethynyl-2’-deoxyuridine assays,while apoptosis was measured by flow cytometry.The migratory and invasive potential of CRC cell lines were deter-mined using wound healing and transwell chamber assays.In vivo studies involved monitoring the growth rate of xenograft tumors.Finally,the underlying molecular mechanism of DARPP-32 was investigated through RNA-sequencing and western blot analyses.RESULTS DARPP-32 was frequently upregulated in CRC and associated with abnormal clinicopathological features in CRC.Overexpression of DARPP-32 was shown to promote cancer cell proliferation,migration,and invasion and reduce apoptosis.DARPP-32 knockdown resulted in the opposite functional effects.Mechanistically,DARPP-32 may regulate the phosphoinositide 3-kinase(PI3K)/AKT signaling pathway in order to carry out its biological function.CONCLUSION DARPP-32 promotes CRC progression via the PI3K/AKT signaling pathway.展开更多
The thermodynamic and kinetic mechanisms of Taixi anthracite during its graphitization process were explored.To understand the variation trends of carbon arrangement order,microcrystal size,and graphitization degree a...The thermodynamic and kinetic mechanisms of Taixi anthracite during its graphitization process were explored.To understand the variation trends of carbon arrangement order,microcrystal size,and graphitization degree against temperature during the graphitization process,a series of experiments were performed using Raman spectroscopy and X-ray diffraction(XRD).Subsequently,the influencing factors of the dominant reaction at different temperatures were analyzed using thermodynamics and kinetics.The results showed that the graphitization process of Taixi anthracite can be divided into three stages from the perspective of reaction thermodynamics and kinetics.Temperature played a crucial role in the formation and growth of a graphitic structure.Meanwhile,multivariate mechanisms coexisted in the graphitization process.At ultrahigh temperatures,the defects of synthetic graphite could not be completely eliminated and perfect graphite crystals could not be produced.At low temperatures,the reaction is mainly controlled by dynamics,while at high temperatures,thermodynamics dominates the direction of the reaction.展开更多
To design a promising Al−Si filler alloy with a relatively low melting-point,good strength and plasticity for the Cu/Al joint,the Cu,Ni,Zr and Er elements were innovatively added to modify the traditional Al−Si eutect...To design a promising Al−Si filler alloy with a relatively low melting-point,good strength and plasticity for the Cu/Al joint,the Cu,Ni,Zr and Er elements were innovatively added to modify the traditional Al−Si eutectic filler.The microstructure and mechanical properties of filler alloys and Cu/Al joints were investigated.The result indicated that the Al−Si−Ni−Cu filler alloys mainly consisted of Al(s,s),Al_(2)(Cu,Ni)and Si(s,s).The Al−10Si−2Ni−6Cu filler alloy exhibited relatively low solidus(521℃)and liquidus(577℃)temperature,good tensile strength(305.8 MPa)and fracture elongation(8.5%).The corresponding Cu/Al joint brazed using Al−10Si−2Ni−6Cu filler was mainly composed of Al_(8)(Mn,Fe)_(2)Si,Al_(2)(Cu,Ni)3,Al(Cu,Ni),Al_(2)(Cu,Ni)and Al(s,s),yielding a shear strength of(90.3±10.7)MPa.The joint strength was further improved to(94.6±2.5)MPa when the joint was brazed using the Al−10Si−2Ni−6Cu−0.2Er−0.2Zr filler alloy.Consequently,the(Cu,Ni,Zr,Er)-modified Al−Si filler alloy was suitable for obtaining high-quality Cu/Al brazed joints.展开更多
By adding mixture of ZrOand carbon, a Zrenhanced composite coating was produced onto an AISI1045 substrate by laser cladding. The microstructure and phase formation, microhardness and wear resistance of the composite ...By adding mixture of ZrOand carbon, a Zrenhanced composite coating was produced onto an AISI1045 substrate by laser cladding. The microstructure and phase formation, microhardness and wear resistance of the composite coating were studied. The experimental results indicate that the composite coating with metallurgical bonding to substrate consists of y-Ni, massive ceramic particles of ZrC,NiZr, NiZr,(Fe,Ni)Cand FeC. The in situ-synthesized ZrC particles are uniformly dispersed in composite coating, which refines the microstructure of composite coating. With different Zr02 and carbon additions, the properties are improved differently. Finally, the fine in situ ZrC particles improve the microhardness of composite coating to HV650, which is nearly 2.7 times that of Ni25 coating. Also, the composite coating has an advantage in wear resistance; it offers better wear resistance when more mixture of ZrOand carbon was added in nickel alloys.展开更多
The machining accuracy of computer numerical control machine tools has always been a focus of the manufacturing industry.Among all errors,thermal error affects the machining accuracy considerably.Because of the signif...The machining accuracy of computer numerical control machine tools has always been a focus of the manufacturing industry.Among all errors,thermal error affects the machining accuracy considerably.Because of the significant impact of Industry 4.0 on machine tools,existing thermal error modeling methods have encountered unprecedented challenges in terms of model complexity and capability of dealing with a large number of time series data.A thermal error modeling method is proposed based on bidirectional long short-term memory(BiLSTM)deep learning,which has good learning ability and a strong capability to handle a large group of dynamic data.A four-layer model framework that includes BiLSTM,a feedforward neural network,and the max pooling is constructed.An elaborately designed algorithm is proposed for better and faster model training.The window length of the input sequence is selected based on the phase space reconstruction of the time series.The model prediction accuracy and model robustness were verified experimentally by three validation tests in which thermal errors predicted by the proposed model were compensated for real workpiece cutting.The average depth variation of the workpiece was reduced from approximately 50μm to less than 2μm after compensation.The reduction in maximum depth variation was more than 85%.The proposed model was proved to be feasible and effective for improving machining accuracy significantly.展开更多
The lower head of reactor pressure vessel (RPV) will endure a great temperature gradient above the phase transition temperature, and the creep and fracture will be the primary failure mode for the RPV material in su...The lower head of reactor pressure vessel (RPV) will endure a great temperature gradient above the phase transition temperature, and the creep and fracture will be the primary failure mode for the RPV material in such a situation. The interrupted creep tests were performed on a typical RPV material, SA508 Gr3 steel, at 800 ℃. The microstructure of different creep stages was examined by scanning electron microscopy and transmission electron microscopy. The results showed that the microscopic damage is mainly induced by creep cavities and coarse second-phase particles. Furthermore, the volume fractions of creep cavities and coarse second-phase particles show a linear relationship with the extended creep time. The second-phase particles are determined to be MoC in the second creep stage and Mo2C in the third creep stage, according to the results of selected-area electron diffraction pattern. Combined with energy-dispersive spectrum analysis, the segregation of precipitates caused by the migration of atoms is finally unveiled, which leads to the coarsening of the particles.展开更多
Purpose:Auditory nerve injury is one of the most common nerve injury complications of skull base fractures.However,there is currently a lack of auxiliary examination methods for its direct diagnosis.The purpose of thi...Purpose:Auditory nerve injury is one of the most common nerve injury complications of skull base fractures.However,there is currently a lack of auxiliary examination methods for its direct diagnosis.The purpose of this study was to find a more efficient and accurate means of diagnosis for auditory nerve injury.Methods:Through retrospectively analyzing the results of brainstem auditory evoked potential(BAEP)and high-resolution CT(HRCT)in 37 patients with hearing impairment following trauma from January 1,2018 to July 31,2020,the role of the two inspection methods in the diagnosis of auditory nerve injury was studied.Inclusion criteria were patient had a clear history of trauma and unilateral hearing impairment after trauma;while exclusion criteria were:(1)severe patient with a Glasgow coma scale score<5 because these patients were classified as severe head injury and admitted to the intensive care unit,(2)patient in the subacute stage admitted 72 h after trauma,and(3)patient with prior hearing impairment before trauma.According to Goodman's classification of hearing impairment,the patients were divided into low/medium/severe injury groups.In addition,patients were divided into HRCT-positive and negative groups for further investigation with their BAEP results.The positive rates of BEAP for each group were observed,and the results were analyzed by Chi-square test(p<0.05,regarded as statistical difference).Results:A total of 37 patients were included,including 21 males and 16 females.All of them were hospitalized patients with GCS score of 6-15 at the time of admission.The BAEP positive rate in the medium and severe injury group was 100%,which was significantly higher than that in the low injury group(27.27%)(p<0.01).The rate of BEAP positivity was significantly higher in the HRCT-positive group(20/30,66.7%)than in the HRCT-negative group(1/7,14.3%)(p<0.05).Twenty patients(54.05%)were both positive for BEAP and HRCT test,and considered to have auditory nerve damage.Six patients(16.22%)were both negative for BEAP and HRCT test,and 10 patients(27.03%)were BAEP-negative but HRCT-positive:all the 16 patients were considered as non-neurological injury.The rest 1 case(2.70%)was BAEP-positive but HRCT-negative,which we speculate may have auditory nerve concussion.Conclusion:By way of BAEP combining with skull base HRCT,we may improve the accuracy of the diagnosis of auditory nerve injury.Such a diagnostic strategy may be beneficial to guiding treatment plans and evaluating prognosis.展开更多
A direct C–H amination reaction of N-Ts-2-Styrylaniline derivatives to realize the synthesis of indole derivatives was developed in the presence of copper salt. A variety of N-Ts-2-Styrylaniline derivatives were tran...A direct C–H amination reaction of N-Ts-2-Styrylaniline derivatives to realize the synthesis of indole derivatives was developed in the presence of copper salt. A variety of N-Ts-2-Styrylaniline derivatives were transformed into the corresponding indole products in good to excellent yield under mild conditions with the oxidation of potassium persulfate.展开更多
In practical operations,the carbon monoxide(CO)distribution in an opposite-wall-firing furnace(OWFF)is characterized by a high concentration near the side walls and a low concentration in the center,accompanied by a s...In practical operations,the carbon monoxide(CO)distribution in an opposite-wall-firing furnace(OWFF)is characterized by a high concentration near the side walls and a low concentration in the center,accompanied by a series of combustionrelated issues.To find the reasons for the CO distribution,a numerical study was conducted on a 660 MWe OWFF.The CO concentration profiles,distribution coefficients of coal and air,mixing coefficients,and the aerodynamic characteristics were extracted for analysis.The CO distribution within the furnace greatly depends on the mixing of coal and air.A mismatch between the aerodynamic behaviors of coal and air causes the non-uniform distribution of CO.Taking into consideration that distinctive flow patterns exist within the different regions,the formation mechanisms of the CO distribution can be divided into two components:(1)In the burner region,the collision of opposite flows leads to the migration of gas and particles toward the side wall which,together with the vortexes formed at furnace corners,is responsible for unburned particles concentrated and oxygenized from the furnace center to the side wall.Thus,high CO concentrations appear in these areas.(2)As the over-fire air(OFA)jet is injected into the furnace,it occupies the central region of furnace and pushes the gas from the burner region outward to the side wall,which is disadvantageous for the mixing effect in the side wall region.As a consequence,a U-shaped distribution of CO concentration is formed.Our results contribute to a theoretical basis for facilitating the control of variation in CO concentration within the furnace.展开更多
An efficient method has been developed for the cascade synthesis of azo[1,2-a]indolones from azoles and2-fluoroaldehydes based on an iron-catalyzed SNAr and a direct acylation reaction.A number of azo[1,2-a]indolones ...An efficient method has been developed for the cascade synthesis of azo[1,2-a]indolones from azoles and2-fluoroaldehydes based on an iron-catalyzed SNAr and a direct acylation reaction.A number of azo[1,2-a]indolones containing different azole rings and substituents were obtained in good yields.展开更多
基金Supported by Chongqing Key Diseases Research and Application Demonstration Program,No.2019ZX003General Project of Chongqing Nature Science Foundation,No.cstc2021jcyj-msxmX0283.
文摘BACKGROUND Dopamine and cyclic adenosine monophosphate(cAMP)-regulated phosphop-rotein with an apparent Mr of 32000(DARPP-32)is a protein that is involved in regulating dopamine and cAMP signaling pathways in the brain.However,recent studies have shown that DARPP-32 is also expressed in other tissues,including colorectal cancer(CRC),where its function is not well understood.AIM To explore the effect of DARPP-32 on CRC progression.METHODS The expression levels of DARPP-32 were assessed in CRC tissues using both quantitative polymerase chain reaction and immunohistochemistry assays.The proliferative capacity of CRC cell lines was evaluated with Cell Counting Kit-8 and 5-ethynyl-2’-deoxyuridine assays,while apoptosis was measured by flow cytometry.The migratory and invasive potential of CRC cell lines were deter-mined using wound healing and transwell chamber assays.In vivo studies involved monitoring the growth rate of xenograft tumors.Finally,the underlying molecular mechanism of DARPP-32 was investigated through RNA-sequencing and western blot analyses.RESULTS DARPP-32 was frequently upregulated in CRC and associated with abnormal clinicopathological features in CRC.Overexpression of DARPP-32 was shown to promote cancer cell proliferation,migration,and invasion and reduce apoptosis.DARPP-32 knockdown resulted in the opposite functional effects.Mechanistically,DARPP-32 may regulate the phosphoinositide 3-kinase(PI3K)/AKT signaling pathway in order to carry out its biological function.CONCLUSION DARPP-32 promotes CRC progression via the PI3K/AKT signaling pathway.
基金financially supported by the China Postdoctoral Science Foundation and China National “Twelfth Five-Year” Plan for Science & Technology (No. 2014BAB01B02)Shenhua Ningxia Coal Industry Group for financial support and providing Taixi anthracite samplesthe support of Advanced Analysis & Computation Center of China University of Mining and Technology
文摘The thermodynamic and kinetic mechanisms of Taixi anthracite during its graphitization process were explored.To understand the variation trends of carbon arrangement order,microcrystal size,and graphitization degree against temperature during the graphitization process,a series of experiments were performed using Raman spectroscopy and X-ray diffraction(XRD).Subsequently,the influencing factors of the dominant reaction at different temperatures were analyzed using thermodynamics and kinetics.The results showed that the graphitization process of Taixi anthracite can be divided into three stages from the perspective of reaction thermodynamics and kinetics.Temperature played a crucial role in the formation and growth of a graphitic structure.Meanwhile,multivariate mechanisms coexisted in the graphitization process.At ultrahigh temperatures,the defects of synthetic graphite could not be completely eliminated and perfect graphite crystals could not be produced.At low temperatures,the reaction is mainly controlled by dynamics,while at high temperatures,thermodynamics dominates the direction of the reaction.
基金the financial support from the Primary Research&Development Plan of Zhejiang Province,China(No.2021C01178)the National MCF Energy R&D Program,China(No.2019YFE03100400)+1 种基金the National Natural Science Foundation of China(Nos.51705457,51975530,52005445,52175368)the Natural Science Foundation of Zhejiang Province,China(Nos.LQ21E050015,LQ21E050018).
文摘To design a promising Al−Si filler alloy with a relatively low melting-point,good strength and plasticity for the Cu/Al joint,the Cu,Ni,Zr and Er elements were innovatively added to modify the traditional Al−Si eutectic filler.The microstructure and mechanical properties of filler alloys and Cu/Al joints were investigated.The result indicated that the Al−Si−Ni−Cu filler alloys mainly consisted of Al(s,s),Al_(2)(Cu,Ni)and Si(s,s).The Al−10Si−2Ni−6Cu filler alloy exhibited relatively low solidus(521℃)and liquidus(577℃)temperature,good tensile strength(305.8 MPa)and fracture elongation(8.5%).The corresponding Cu/Al joint brazed using Al−10Si−2Ni−6Cu filler was mainly composed of Al_(8)(Mn,Fe)_(2)Si,Al_(2)(Cu,Ni)3,Al(Cu,Ni),Al_(2)(Cu,Ni)and Al(s,s),yielding a shear strength of(90.3±10.7)MPa.The joint strength was further improved to(94.6±2.5)MPa when the joint was brazed using the Al−10Si−2Ni−6Cu−0.2Er−0.2Zr filler alloy.Consequently,the(Cu,Ni,Zr,Er)-modified Al−Si filler alloy was suitable for obtaining high-quality Cu/Al brazed joints.
基金financially supported by the National Natural Science Foundation of China (No.51275303)
文摘By adding mixture of ZrOand carbon, a Zrenhanced composite coating was produced onto an AISI1045 substrate by laser cladding. The microstructure and phase formation, microhardness and wear resistance of the composite coating were studied. The experimental results indicate that the composite coating with metallurgical bonding to substrate consists of y-Ni, massive ceramic particles of ZrC,NiZr, NiZr,(Fe,Ni)Cand FeC. The in situ-synthesized ZrC particles are uniformly dispersed in composite coating, which refines the microstructure of composite coating. With different Zr02 and carbon additions, the properties are improved differently. Finally, the fine in situ ZrC particles improve the microhardness of composite coating to HV650, which is nearly 2.7 times that of Ni25 coating. Also, the composite coating has an advantage in wear resistance; it offers better wear resistance when more mixture of ZrOand carbon was added in nickel alloys.
基金sponsored by the National Natural Science Foundation of Major Special Instruments(Grant No.51527806)the National Natural Science Foundation Projects of the People’s Republic of China(Grant No.51975372).
文摘The machining accuracy of computer numerical control machine tools has always been a focus of the manufacturing industry.Among all errors,thermal error affects the machining accuracy considerably.Because of the significant impact of Industry 4.0 on machine tools,existing thermal error modeling methods have encountered unprecedented challenges in terms of model complexity and capability of dealing with a large number of time series data.A thermal error modeling method is proposed based on bidirectional long short-term memory(BiLSTM)deep learning,which has good learning ability and a strong capability to handle a large group of dynamic data.A four-layer model framework that includes BiLSTM,a feedforward neural network,and the max pooling is constructed.An elaborately designed algorithm is proposed for better and faster model training.The window length of the input sequence is selected based on the phase space reconstruction of the time series.The model prediction accuracy and model robustness were verified experimentally by three validation tests in which thermal errors predicted by the proposed model were compensated for real workpiece cutting.The average depth variation of the workpiece was reduced from approximately 50μm to less than 2μm after compensation.The reduction in maximum depth variation was more than 85%.The proposed model was proved to be feasible and effective for improving machining accuracy significantly.
基金This research was supported by the National Natural Science Foundation of China (51575489) and National 13th Five-Year Key Technologies R&D Program (No. 2016YFC0801902).
文摘The lower head of reactor pressure vessel (RPV) will endure a great temperature gradient above the phase transition temperature, and the creep and fracture will be the primary failure mode for the RPV material in such a situation. The interrupted creep tests were performed on a typical RPV material, SA508 Gr3 steel, at 800 ℃. The microstructure of different creep stages was examined by scanning electron microscopy and transmission electron microscopy. The results showed that the microscopic damage is mainly induced by creep cavities and coarse second-phase particles. Furthermore, the volume fractions of creep cavities and coarse second-phase particles show a linear relationship with the extended creep time. The second-phase particles are determined to be MoC in the second creep stage and Mo2C in the third creep stage, according to the results of selected-area electron diffraction pattern. Combined with energy-dispersive spectrum analysis, the segregation of precipitates caused by the migration of atoms is finally unveiled, which leads to the coarsening of the particles.
文摘Purpose:Auditory nerve injury is one of the most common nerve injury complications of skull base fractures.However,there is currently a lack of auxiliary examination methods for its direct diagnosis.The purpose of this study was to find a more efficient and accurate means of diagnosis for auditory nerve injury.Methods:Through retrospectively analyzing the results of brainstem auditory evoked potential(BAEP)and high-resolution CT(HRCT)in 37 patients with hearing impairment following trauma from January 1,2018 to July 31,2020,the role of the two inspection methods in the diagnosis of auditory nerve injury was studied.Inclusion criteria were patient had a clear history of trauma and unilateral hearing impairment after trauma;while exclusion criteria were:(1)severe patient with a Glasgow coma scale score<5 because these patients were classified as severe head injury and admitted to the intensive care unit,(2)patient in the subacute stage admitted 72 h after trauma,and(3)patient with prior hearing impairment before trauma.According to Goodman's classification of hearing impairment,the patients were divided into low/medium/severe injury groups.In addition,patients were divided into HRCT-positive and negative groups for further investigation with their BAEP results.The positive rates of BEAP for each group were observed,and the results were analyzed by Chi-square test(p<0.05,regarded as statistical difference).Results:A total of 37 patients were included,including 21 males and 16 females.All of them were hospitalized patients with GCS score of 6-15 at the time of admission.The BAEP positive rate in the medium and severe injury group was 100%,which was significantly higher than that in the low injury group(27.27%)(p<0.01).The rate of BEAP positivity was significantly higher in the HRCT-positive group(20/30,66.7%)than in the HRCT-negative group(1/7,14.3%)(p<0.05).Twenty patients(54.05%)were both positive for BEAP and HRCT test,and considered to have auditory nerve damage.Six patients(16.22%)were both negative for BEAP and HRCT test,and 10 patients(27.03%)were BAEP-negative but HRCT-positive:all the 16 patients were considered as non-neurological injury.The rest 1 case(2.70%)was BAEP-positive but HRCT-negative,which we speculate may have auditory nerve concussion.Conclusion:By way of BAEP combining with skull base HRCT,we may improve the accuracy of the diagnosis of auditory nerve injury.Such a diagnostic strategy may be beneficial to guiding treatment plans and evaluating prognosis.
基金financially supported by the National Natural Science Foundation of China(Nos.21272169,21302135)the Key Innovation Team of Science & Technology in Zhejiang Province(No.2010R50018-10)+1 种基金the Science and Technology Bureau of Taizhou(No.08KY10)the Key Disciplines of Applied Chemistry of Zhejiang Province,Taizhou University
文摘A direct C–H amination reaction of N-Ts-2-Styrylaniline derivatives to realize the synthesis of indole derivatives was developed in the presence of copper salt. A variety of N-Ts-2-Styrylaniline derivatives were transformed into the corresponding indole products in good to excellent yield under mild conditions with the oxidation of potassium persulfate.
文摘In practical operations,the carbon monoxide(CO)distribution in an opposite-wall-firing furnace(OWFF)is characterized by a high concentration near the side walls and a low concentration in the center,accompanied by a series of combustionrelated issues.To find the reasons for the CO distribution,a numerical study was conducted on a 660 MWe OWFF.The CO concentration profiles,distribution coefficients of coal and air,mixing coefficients,and the aerodynamic characteristics were extracted for analysis.The CO distribution within the furnace greatly depends on the mixing of coal and air.A mismatch between the aerodynamic behaviors of coal and air causes the non-uniform distribution of CO.Taking into consideration that distinctive flow patterns exist within the different regions,the formation mechanisms of the CO distribution can be divided into two components:(1)In the burner region,the collision of opposite flows leads to the migration of gas and particles toward the side wall which,together with the vortexes formed at furnace corners,is responsible for unburned particles concentrated and oxygenized from the furnace center to the side wall.Thus,high CO concentrations appear in these areas.(2)As the over-fire air(OFA)jet is injected into the furnace,it occupies the central region of furnace and pushes the gas from the burner region outward to the side wall,which is disadvantageous for the mixing effect in the side wall region.As a consequence,a U-shaped distribution of CO concentration is formed.Our results contribute to a theoretical basis for facilitating the control of variation in CO concentration within the furnace.
基金financially supported by the Natural Science Foundation of China(Nos.21302135 and 21272169)Taizhou Science & Technology program(No.111ZD02)
文摘An efficient method has been developed for the cascade synthesis of azo[1,2-a]indolones from azoles and2-fluoroaldehydes based on an iron-catalyzed SNAr and a direct acylation reaction.A number of azo[1,2-a]indolones containing different azole rings and substituents were obtained in good yields.