BACKGROUND Insomnia is a disease where individuals cannot maintain a steady and stable sleep state or fail to fall asleep.Western medicine mainly uses sedatives and hypnotic drugs to treat insomnia,and long-term use i...BACKGROUND Insomnia is a disease where individuals cannot maintain a steady and stable sleep state or fail to fall asleep.Western medicine mainly uses sedatives and hypnotic drugs to treat insomnia,and long-term use is prone to drug resistance and other adverse reactions.Acupuncture has a good curative effect and unique advantages in the treatment of insomnia.AIM To explore the molecular mechanism of acupuncture at Back-Shu point for the treatment of insomnia.METHODS We first prepared a rat model of insomnia,and then carried out acupuncture for 7 consecutive days.After treatment,the sleep time and general behavior of the rats were determined.The Morris water maze test was used to assess the learning ability and spatial memory ability of the rats.The expression levels of inflammatory cytokines in serum and the hippocampus were detected by ELISA.qRTPCR was used to detect the mRNA expression changes in the ERK/NF-κB signaling pathway.Western blot and immunohistochemistry were carried out to evaluate the protein expression levels of RAF-1,MEK-2,ERK1/2 and NF-κB.RESULTS Acupuncture can prolong sleep duration,and improve mental state,activity,diet volume,learning ability and spatial memory.In addition,acupuncture increased the release of 1L-1β,1L-6 and TNF-αin serum and the hippocampus and inhibited the mRNA and protein expression of the ERK/NF-κB signaling pathway.CONCLUSION These findings suggest that acupuncture at Back-Shu point can inhibit the ERK/NF-κB signaling pathway and treat insomnia by increasing the release of inflammatory cytokines in the hippocampus.展开更多
Background:Early recurrence results in poor prognosis of patients with hepatocellular carcinoma(HCC)after liver transplantation(LT).This study aimed to explore the value of computed tomography(CT)-based radiomics nomo...Background:Early recurrence results in poor prognosis of patients with hepatocellular carcinoma(HCC)after liver transplantation(LT).This study aimed to explore the value of computed tomography(CT)-based radiomics nomogram in predicting early recurrence of patients with HCC after LT.Methods:A cohort of 151 patients with HCC who underwent LT between December 2013 and July 2019 were retrospectively enrolled.A total of 1218 features were extracted from enhanced CT images.The least absolute shrinkage and selection operator algorithm(LASSO)logistic regression was used for dimension reduction and radiomics signature building.The clinical model was constructed after the analysis of clin-ical factors,and the nomogram was constructed by introducing the radiomics signature into the clinical model.The predictive performance and clinical usefulness of the three models were evaluated using re-ceiver operating characteristic(ROC)curve analysis and decision curve analysis(DCA),respectively.Cali-bration curves were plotted to assess the calibration of the nomogram.Results:There were significant differences in radiomics signature among early recurrence patients and non-early recurrence patients in the training cohort(P<0.001)and validation cohort(P<0.001).The nomogram showed the best predictive performance,with the largest area under the ROC curve in the training(0.882)and validation(0.917)cohorts.Hosmer-Lemeshow testing confirmed that the nomogram showed good calibration in the training(P=0.138)and validation(P=0.396)cohorts.DCA showed if the threshold probability is within 0.06-1,the nomogram had better clinical usefulness than the clinical model.Conclusions:Our CT-based radiomics nomogram can preoperatively predict the risk of early recurrence in patients with HCC after LT.展开更多
We study the connections between the pairwise velocity moment generating function G(k_(‖),r)and redshift space distortion(RSD)modeling.Here k_(‖)is the Fourier wavevector parallel to the line of sight,and r is the p...We study the connections between the pairwise velocity moment generating function G(k_(‖),r)and redshift space distortion(RSD)modeling.Here k_(‖)is the Fourier wavevector parallel to the line of sight,and r is the pair separation vector.We demonstrate its usage by two examples.(1)Besides the known relations between G and the RSD power spectrum(and the correlation function),we propose a new RSD statistics Ps(k_(‖),r_(丄))whose connection to G is convenient to evaluate numerically.(2)We then develop a fast method to numerically evaluate G,and apply it to a high resolution N-body simulation.We find that G(ln G)shows complicated dependence on k_(‖)beyond the linear and quadratic dependencies.This not only shows inaccuracy in some existing models and identifies sources of inaccuracy but also provides possible ways of improving the RSD modeling.Consequently,more comprehensive investigations on G are needed to fully explore the usage of G in RSD modeling.展开更多
With the continuous development of science and technology,the increasingly severe service environment makes people put forward higher requirements for the performance of alloy steel.Tungsten has unique properties such...With the continuous development of science and technology,the increasingly severe service environment makes people put forward higher requirements for the performance of alloy steel.Tungsten has unique properties such as excellent strength,high density and good hardness,and its addition as an alloying element will change the properties of alloy steel.This paper aims to summarize the effect of the addition of tungsten on the micro structure and mechanical properties of alloy steel.The background of research and application of tungsten alloyed steel is presented initially.Then,the preparation methods of tungsten alloyed steel are described.Next,the effect of tungsten incorporation on the microstructure of alloy steel is reviewed.Finally,the effects of tungsten addition on the mechanical properties,corrosion resistance and hydrogen embrittlement resistance of the alloy steel are reviewed.This review provides an outlook on the development of tungsten alloyed steel,which will stimulate more in-depth research and ultimately promote the practical application of tungsten alloyed steel.展开更多
Corrugated cold roll bonding(CCRB) produces metal composite plate with improved mechanical properties compared with conventional methods,but the interfacial mechanism is not fully understood.Here,Cu/Al composite plate...Corrugated cold roll bonding(CCRB) produces metal composite plate with improved mechanical properties compared with conventional methods,but the interfacial mechanism is not fully understood.Here,Cu/Al composite plate with good plate shape was produced by CCRB,and the bonding mechanism and strength along the corrugated interface were studied by experiments and finite element simulations.The results showed that the average bonding strength of Cu/Al composite plate produced by CCRB was nearly twice that of conventional composite plate at an average reduction of 40% during rolling.Strong friction shear stresses occurred at the interface of the corrugated composite plate,which promoted the plastic deformation of the metals and accelerated the rupture of the brittle interfacial layer.Electron backscattered diffraction analysis showed that higher degrees of grain elongation and refinement occurred in the matrices at the front waist and trough due to the stronger normal and shear stresses.Energy-dispersive spectroscopy line scans showed that the thickest atomic diffusion layer occurred at the front waist.The present combination of experimental and computational analyses provides insights into the underlying mechanism of mechanically improved metal composites prepared by CCRB.展开更多
Hot compression tests were carried out in the temperature range of 1 223-1 473 Kand strain rate range of0.01-30s^-1 to investigate the flow behavior and microstructural evolution of super duplex stainless steel 2507（...Hot compression tests were carried out in the temperature range of 1 223-1 473 Kand strain rate range of0.01-30s^-1 to investigate the flow behavior and microstructural evolution of super duplex stainless steel 2507（SDSS2507）.It is found that most of the flow curves exhibit a characteristic of dynamic recrystallization（DRX）and the flow stress increases with the decrease of temperature and the increase of strain rate.The apparent activation energy Qof SDSS2507 with varying true strain and strain rate is determined.As the strain increases,the value of Qdeclines in different ways with varying strain rate.The microstructural evolution characteristics and the strain partition between the two constituent phases are significantly affected by the Zener-Hollomon parameter（Z）.At a lower lnZ,dynamic recovery（DRV）and continuous dynamic recrystallization（CDRX）of the ferrite dominate the softening mechanism during the compression.At this time,steady state deformation takes place at the last stage of deformation.In contrast,a higher lnZ will facilitate the plastic deformation of the austenite and then activate the discontinuous dynamic recrystallization（DDRX）of the austenite,which leads to a continuous decline of the flow stress even at the last deformation stage together with CDRX of the ferrite.展开更多
文摘BACKGROUND Insomnia is a disease where individuals cannot maintain a steady and stable sleep state or fail to fall asleep.Western medicine mainly uses sedatives and hypnotic drugs to treat insomnia,and long-term use is prone to drug resistance and other adverse reactions.Acupuncture has a good curative effect and unique advantages in the treatment of insomnia.AIM To explore the molecular mechanism of acupuncture at Back-Shu point for the treatment of insomnia.METHODS We first prepared a rat model of insomnia,and then carried out acupuncture for 7 consecutive days.After treatment,the sleep time and general behavior of the rats were determined.The Morris water maze test was used to assess the learning ability and spatial memory ability of the rats.The expression levels of inflammatory cytokines in serum and the hippocampus were detected by ELISA.qRTPCR was used to detect the mRNA expression changes in the ERK/NF-κB signaling pathway.Western blot and immunohistochemistry were carried out to evaluate the protein expression levels of RAF-1,MEK-2,ERK1/2 and NF-κB.RESULTS Acupuncture can prolong sleep duration,and improve mental state,activity,diet volume,learning ability and spatial memory.In addition,acupuncture increased the release of 1L-1β,1L-6 and TNF-αin serum and the hippocampus and inhibited the mRNA and protein expression of the ERK/NF-κB signaling pathway.CONCLUSION These findings suggest that acupuncture at Back-Shu point can inhibit the ERK/NF-κB signaling pathway and treat insomnia by increasing the release of inflammatory cytokines in the hippocampus.
基金the National Key Research and Development Program of China(2019YFC0118104)the National Natural Science Foundation of China(82001808)+2 种基金the Beijing Natural Science Foundation(7222319)the Beijing Munici-pal Science&Technology Commission(Z21100002921047)the Capital’s Clinical Applied Research Project(Z181100001718013).
文摘Background:Early recurrence results in poor prognosis of patients with hepatocellular carcinoma(HCC)after liver transplantation(LT).This study aimed to explore the value of computed tomography(CT)-based radiomics nomogram in predicting early recurrence of patients with HCC after LT.Methods:A cohort of 151 patients with HCC who underwent LT between December 2013 and July 2019 were retrospectively enrolled.A total of 1218 features were extracted from enhanced CT images.The least absolute shrinkage and selection operator algorithm(LASSO)logistic regression was used for dimension reduction and radiomics signature building.The clinical model was constructed after the analysis of clin-ical factors,and the nomogram was constructed by introducing the radiomics signature into the clinical model.The predictive performance and clinical usefulness of the three models were evaluated using re-ceiver operating characteristic(ROC)curve analysis and decision curve analysis(DCA),respectively.Cali-bration curves were plotted to assess the calibration of the nomogram.Results:There were significant differences in radiomics signature among early recurrence patients and non-early recurrence patients in the training cohort(P<0.001)and validation cohort(P<0.001).The nomogram showed the best predictive performance,with the largest area under the ROC curve in the training(0.882)and validation(0.917)cohorts.Hosmer-Lemeshow testing confirmed that the nomogram showed good calibration in the training(P=0.138)and validation(P=0.396)cohorts.DCA showed if the threshold probability is within 0.06-1,the nomogram had better clinical usefulness than the clinical model.Conclusions:Our CT-based radiomics nomogram can preoperatively predict the risk of early recurrence in patients with HCC after LT.
基金supported by the National Natural Science Foundation of China(Grant No.11621303)。
文摘We study the connections between the pairwise velocity moment generating function G(k_(‖),r)and redshift space distortion(RSD)modeling.Here k_(‖)is the Fourier wavevector parallel to the line of sight,and r is the pair separation vector.We demonstrate its usage by two examples.(1)Besides the known relations between G and the RSD power spectrum(and the correlation function),we propose a new RSD statistics Ps(k_(‖),r_(丄))whose connection to G is convenient to evaluate numerically.(2)We then develop a fast method to numerically evaluate G,and apply it to a high resolution N-body simulation.We find that G(ln G)shows complicated dependence on k_(‖)beyond the linear and quadratic dependencies.This not only shows inaccuracy in some existing models and identifies sources of inaccuracy but also provides possible ways of improving the RSD modeling.Consequently,more comprehensive investigations on G are needed to fully explore the usage of G in RSD modeling.
基金supported by the Central Government Guided Local Science and Technology Development Fund Project(Grant No.YDZJSX2021A006)the Fund Program for the Scientific Activities of Selected Returned Overseas Professionals in Shanxi Province(Grant No.20210035)the Research Project Supported by Shanxi Scholarship Council of China(Grant No.2020-037)。
文摘With the continuous development of science and technology,the increasingly severe service environment makes people put forward higher requirements for the performance of alloy steel.Tungsten has unique properties such as excellent strength,high density and good hardness,and its addition as an alloying element will change the properties of alloy steel.This paper aims to summarize the effect of the addition of tungsten on the micro structure and mechanical properties of alloy steel.The background of research and application of tungsten alloyed steel is presented initially.Then,the preparation methods of tungsten alloyed steel are described.Next,the effect of tungsten incorporation on the microstructure of alloy steel is reviewed.Finally,the effects of tungsten addition on the mechanical properties,corrosion resistance and hydrogen embrittlement resistance of the alloy steel are reviewed.This review provides an outlook on the development of tungsten alloyed steel,which will stimulate more in-depth research and ultimately promote the practical application of tungsten alloyed steel.
基金financially supported by the Major Program of National Natural Science Foundation of China (No. U1710254)Shanxi Province Science and Technology Major Projects (No.20181101008)+1 种基金the Scientific and Technological Progress of Shanxi Province Colleges and Universities (No.2017132)the National Natural Science Foundation of China (Nos.51974196, 51975398,and 51905372)。
文摘Corrugated cold roll bonding(CCRB) produces metal composite plate with improved mechanical properties compared with conventional methods,but the interfacial mechanism is not fully understood.Here,Cu/Al composite plate with good plate shape was produced by CCRB,and the bonding mechanism and strength along the corrugated interface were studied by experiments and finite element simulations.The results showed that the average bonding strength of Cu/Al composite plate produced by CCRB was nearly twice that of conventional composite plate at an average reduction of 40% during rolling.Strong friction shear stresses occurred at the interface of the corrugated composite plate,which promoted the plastic deformation of the metals and accelerated the rupture of the brittle interfacial layer.Electron backscattered diffraction analysis showed that higher degrees of grain elongation and refinement occurred in the matrices at the front waist and trough due to the stronger normal and shear stresses.Energy-dispersive spectroscopy line scans showed that the thickest atomic diffusion layer occurred at the front waist.The present combination of experimental and computational analyses provides insights into the underlying mechanism of mechanically improved metal composites prepared by CCRB.
基金Item Sponsored by National Key Technology Research and Development Program of China(2012BAE04B01)
文摘Hot compression tests were carried out in the temperature range of 1 223-1 473 Kand strain rate range of0.01-30s^-1 to investigate the flow behavior and microstructural evolution of super duplex stainless steel 2507（SDSS2507）.It is found that most of the flow curves exhibit a characteristic of dynamic recrystallization（DRX）and the flow stress increases with the decrease of temperature and the increase of strain rate.The apparent activation energy Qof SDSS2507 with varying true strain and strain rate is determined.As the strain increases,the value of Qdeclines in different ways with varying strain rate.The microstructural evolution characteristics and the strain partition between the two constituent phases are significantly affected by the Zener-Hollomon parameter（Z）.At a lower lnZ,dynamic recovery（DRV）and continuous dynamic recrystallization（CDRX）of the ferrite dominate the softening mechanism during the compression.At this time,steady state deformation takes place at the last stage of deformation.In contrast,a higher lnZ will facilitate the plastic deformation of the austenite and then activate the discontinuous dynamic recrystallization（DDRX）of the austenite,which leads to a continuous decline of the flow stress even at the last deformation stage together with CDRX of the ferrite.
