AIM:To evaluate the diagnostic role of serum RASSF1A promoter hypermethylation in gastric and colorectal adenocarcinoma. METHODS:Methylation-specific polymerase chain reaction (MSPCR) was used to examine the promo...AIM:To evaluate the diagnostic role of serum RASSF1A promoter hypermethylation in gastric and colorectal adenocarcinoma. METHODS:Methylation-specific polymerase chain reaction (MSPCR) was used to examine the promoter methylation status of the serum RASSF1A gene in 47 gastric adenocarcinoma patients, 45 colorectal adenocarcinoma patients, 60 patients with benign gastrointestinal disease (30 with benign gastric disease and 30 with benign colorectal disease), and 30 healthy donor controls. Apaired study of RASSF1A promoter methylation status in primary tumor, adjacent normal tissue, and postopertive serum were conducted in 25 gastric and colorectal adenocarcinoma patients who later were underwent surgical therapy. RESULTS:The frequencies of detection of serum RASSF1A promoter hypermethylation in gastric (34.0%) and colorectal (28.9%) adenocarcinoma patients were significantly higher than those in patients with benign gastric (3.3%) or colorectal (6.7%) disease or in healthy donors (0%) (P 〈 0.01). The methylation status of RASSF1A promoter in serum samples was consistent with that in paired primary tumors, and the MSPCR results for RASSF1A promoter methylation status in paired preoperative samples were consistent with those in postoperative serum samples. The serum RASSF1A promoter hypermethylation did not correlate with patient sex, age, tumor differentiation grade, surgical therapy, or serum carcinoembryonic antigen level. Although the serum RASSF1A promoter hypermethylation frequency tended to be higher in patients with distant metastases, there was no correlation between methylation status and metastasis. CONCLUSION:Aberrant CpG island methylation within the promoter region of RASSF1A is a promising biomarker for gastric and colorectal cancer.展开更多
Three different kinds of PELE(the penetrator with lateral efficiency) were launched by ballistic artillery to impact the multi-layer spaced metal target plates.The lmpact velocities of the projectiles were measured by...Three different kinds of PELE(the penetrator with lateral efficiency) were launched by ballistic artillery to impact the multi-layer spaced metal target plates.The lmpact velocities of the projectiles were measured by the velocity measuring system.The damage degree and process of each laye r of target plate impacted by the three kinds of projectiles were analyzed.The experimental results show that all the three kinds of projectiles have the effect of expanding holes on the multi-layer spaced metal target plates.For the normal structure PELE(without layered) with tungsten alloy jacket and the radial layered PELE with tungsten alloy jacket,the diameters of holes on the seco nd layer of plates are 3.36 times and 3.76 times of the diameter of the projectile,re spectively.For radial layered PELE with W/Zr-based amorphous composite jacket,due to the large number of tungsten wires dispersed after the impact,the diameter of the holes on the four-layer spaced plates can reach 2.4 times,3.04 times,5.36 times and 2.68 times of the diameter of the projectile.Besides,the normal structure PELE with tungsten alloy jacket and the radial layered PELE whit tungsten alloy jacket formed a large number of fragments impact marks on the third target plate.Although the number of fragments penetrating the third target plate is not as large as that of the normal structure PELE,the area of dispersion of fragments impact craters on the third target plate is larger by the radial layered PELE.The radial layered PELE with W/Zr-based amorphous composite jacket released a lot of heat energy due to the impact of the matrix material,and formed a large area of ablation marks on the last three target plates.展开更多
Impact velocity(v0),target strength(fc)and target thickness(hc)are important factors affecting opening damage■of PELE penetration into RC target.In this paper,based on the three influence factors of v0,fc and hc,expe...Impact velocity(v0),target strength(fc)and target thickness(hc)are important factors affecting opening damage■of PELE penetration into RC target.In this paper,based on the three influence factors of v0,fc and hc,experimental and numerical simulation studies on PELE penetration into RC target were carried out.The study results show that:(1)Since interaction force(or penetration resistance)between projectile and target is positively correlated with v0 and fc,with the increase of v0 and fc,deformation mode of jacket is changed from small bending deformation to large bending deformation and then to curling deformation.Therefore,the variation of jacket deformation mode causes opening diameter of RC target to increase first and then to decrease.It is found that the two factors approximately satisfy a quadratic function relationship,respectively.(2)For PELE projectile penetrating RC targets with thickness of 80-400 mm,the opening diameter of six sets of RC targets grows from 240 to 500 mm,and hc with■approximately satisfy a linear relationship.(3)Based on the above study results,the relationship between two dimensionless parameters■and dimensionless opening diameter■was determined.Combined with the results of previous research,a dimensionless opening diameter model■was established.By tests verified,the test results are all within±10%error of the theoretical model,which verifies the accuracy of the model.展开更多
When a penetrator with enhanced lateral effect(PELE) impacts on a reinforced concrete(RC) target,the target is damaged with a large opening.An understanding of how PELE projectile parameters affect the opening dimensi...When a penetrator with enhanced lateral effect(PELE) impacts on a reinforced concrete(RC) target,the target is damaged with a large opening.An understanding of how PELE projectile parameters affect the opening dimension,is essential for effective design of the PELE projectile.In this study,under the condition that the impact velocity and target parameters(strength and thickness) were fixed values,the important influence factors of the PELE(jacket wall thickness B,jacket material strength Y1,filling material strength Y2 and angle of monolithic jacket θ) were determined by a dimensional analysis.Tests and simulations of the PELE penetrating the RC target were conducted to analyze the influence of these factors on opening diameter(D,an equivalent diameter under relative kinetic energy).Based on the test and simulation results,it is found that the influence of these factors B,Y1 and θ on the deformation mode of the jacket shows a similar trend:as values of the three factors decrease,the jacket deforms from small bending deformation to large one,and then to curling deformation.This causes the opening diameter to first increase with the decrease of these three factors,and then decreases.It is well known that the bending resistance of the jacket is related to these factors B,Y1 and θ.Therefore,a plastic limit bending moment(M0) of the jacket was quoted to characterize the influence of these factors on the bending deformation of the jacket and the opening diameter of the target.The influence factor Y2 causes D to first increase with the increase of Y2,and then decreases.A formula was developed to predict the opening diameter,whose influence parameters were considered in a dimensionless way.It has been shown that the dimensionless opening diameter D/d1 is dependent on two dimensionless parameters■ and■,where d1 and fc are the outer diameter of the projectile and the compressive strength of the target,respectively.展开更多
The efficacy of traditional treatment for post-traumatic stress disorder(PTSD)is still unsatisfactory.Repetitive transcranial magnetic stimulation(rTMS)has been widely used in the treatment of various types of mental ...The efficacy of traditional treatment for post-traumatic stress disorder(PTSD)is still unsatisfactory.Repetitive transcranial magnetic stimulation(rTMS)has been widely used in the treatment of various types of mental disorders,including PTSD.Although rTMS has been demonstrated to be effective in many cases,there are still arguments regarding its mechanism and protocol.This review aims to summarize the origin,development,principle,and future direction of rTMS and introduce this neuro-stimulation therapy to relevant clinicians.展开更多
文摘AIM:To evaluate the diagnostic role of serum RASSF1A promoter hypermethylation in gastric and colorectal adenocarcinoma. METHODS:Methylation-specific polymerase chain reaction (MSPCR) was used to examine the promoter methylation status of the serum RASSF1A gene in 47 gastric adenocarcinoma patients, 45 colorectal adenocarcinoma patients, 60 patients with benign gastrointestinal disease (30 with benign gastric disease and 30 with benign colorectal disease), and 30 healthy donor controls. Apaired study of RASSF1A promoter methylation status in primary tumor, adjacent normal tissue, and postopertive serum were conducted in 25 gastric and colorectal adenocarcinoma patients who later were underwent surgical therapy. RESULTS:The frequencies of detection of serum RASSF1A promoter hypermethylation in gastric (34.0%) and colorectal (28.9%) adenocarcinoma patients were significantly higher than those in patients with benign gastric (3.3%) or colorectal (6.7%) disease or in healthy donors (0%) (P 〈 0.01). The methylation status of RASSF1A promoter in serum samples was consistent with that in paired primary tumors, and the MSPCR results for RASSF1A promoter methylation status in paired preoperative samples were consistent with those in postoperative serum samples. The serum RASSF1A promoter hypermethylation did not correlate with patient sex, age, tumor differentiation grade, surgical therapy, or serum carcinoembryonic antigen level. Although the serum RASSF1A promoter hypermethylation frequency tended to be higher in patients with distant metastases, there was no correlation between methylation status and metastasis. CONCLUSION:Aberrant CpG island methylation within the promoter region of RASSF1A is a promising biomarker for gastric and colorectal cancer.
基金supported by National Natural Science Foundation of China(Grant No.11802141)Postgraduate Research&Practice Innovation Program of Jiangsu Province(Grant No.KYCX18_0465)。
文摘Three different kinds of PELE(the penetrator with lateral efficiency) were launched by ballistic artillery to impact the multi-layer spaced metal target plates.The lmpact velocities of the projectiles were measured by the velocity measuring system.The damage degree and process of each laye r of target plate impacted by the three kinds of projectiles were analyzed.The experimental results show that all the three kinds of projectiles have the effect of expanding holes on the multi-layer spaced metal target plates.For the normal structure PELE(without layered) with tungsten alloy jacket and the radial layered PELE with tungsten alloy jacket,the diameters of holes on the seco nd layer of plates are 3.36 times and 3.76 times of the diameter of the projectile,re spectively.For radial layered PELE with W/Zr-based amorphous composite jacket,due to the large number of tungsten wires dispersed after the impact,the diameter of the holes on the four-layer spaced plates can reach 2.4 times,3.04 times,5.36 times and 2.68 times of the diameter of the projectile.Besides,the normal structure PELE with tungsten alloy jacket and the radial layered PELE whit tungsten alloy jacket formed a large number of fragments impact marks on the third target plate.Although the number of fragments penetrating the third target plate is not as large as that of the normal structure PELE,the area of dispersion of fragments impact craters on the third target plate is larger by the radial layered PELE.The radial layered PELE with W/Zr-based amorphous composite jacket released a lot of heat energy due to the impact of the matrix material,and formed a large area of ablation marks on the last three target plates.
基金supported by the National Natural Science Foundation of China(Grant No:11772160,11472008,11802141)Opening Project of State Key Laboratory of Explosion Science and Technology,Beijing Institute of Technology(KFJJ18-01M)。
文摘Impact velocity(v0),target strength(fc)and target thickness(hc)are important factors affecting opening damage■of PELE penetration into RC target.In this paper,based on the three influence factors of v0,fc and hc,experimental and numerical simulation studies on PELE penetration into RC target were carried out.The study results show that:(1)Since interaction force(or penetration resistance)between projectile and target is positively correlated with v0 and fc,with the increase of v0 and fc,deformation mode of jacket is changed from small bending deformation to large bending deformation and then to curling deformation.Therefore,the variation of jacket deformation mode causes opening diameter of RC target to increase first and then to decrease.It is found that the two factors approximately satisfy a quadratic function relationship,respectively.(2)For PELE projectile penetrating RC targets with thickness of 80-400 mm,the opening diameter of six sets of RC targets grows from 240 to 500 mm,and hc with■approximately satisfy a linear relationship.(3)Based on the above study results,the relationship between two dimensionless parameters■and dimensionless opening diameter■was determined.Combined with the results of previous research,a dimensionless opening diameter model■was established.By tests verified,the test results are all within±10%error of the theoretical model,which verifies the accuracy of the model.
基金supported by the National Natural Science Foundation of China (Grant No: 11472008, 11772160, 11802141)the Opening Project of State Key Laboratory of Explosion Science and Technology (KFJJ18-01M), Beijing Institute of Technology。
文摘When a penetrator with enhanced lateral effect(PELE) impacts on a reinforced concrete(RC) target,the target is damaged with a large opening.An understanding of how PELE projectile parameters affect the opening dimension,is essential for effective design of the PELE projectile.In this study,under the condition that the impact velocity and target parameters(strength and thickness) were fixed values,the important influence factors of the PELE(jacket wall thickness B,jacket material strength Y1,filling material strength Y2 and angle of monolithic jacket θ) were determined by a dimensional analysis.Tests and simulations of the PELE penetrating the RC target were conducted to analyze the influence of these factors on opening diameter(D,an equivalent diameter under relative kinetic energy).Based on the test and simulation results,it is found that the influence of these factors B,Y1 and θ on the deformation mode of the jacket shows a similar trend:as values of the three factors decrease,the jacket deforms from small bending deformation to large one,and then to curling deformation.This causes the opening diameter to first increase with the decrease of these three factors,and then decreases.It is well known that the bending resistance of the jacket is related to these factors B,Y1 and θ.Therefore,a plastic limit bending moment(M0) of the jacket was quoted to characterize the influence of these factors on the bending deformation of the jacket and the opening diameter of the target.The influence factor Y2 causes D to first increase with the increase of Y2,and then decreases.A formula was developed to predict the opening diameter,whose influence parameters were considered in a dimensionless way.It has been shown that the dimensionless opening diameter D/d1 is dependent on two dimensionless parameters■ and■,where d1 and fc are the outer diameter of the projectile and the compressive strength of the target,respectively.
基金Science and Technology Innovation Plan of Hunan,China,No.2018JJ2592Hunan Key Research and Development Program,No.2018SK2136.
文摘The efficacy of traditional treatment for post-traumatic stress disorder(PTSD)is still unsatisfactory.Repetitive transcranial magnetic stimulation(rTMS)has been widely used in the treatment of various types of mental disorders,including PTSD.Although rTMS has been demonstrated to be effective in many cases,there are still arguments regarding its mechanism and protocol.This review aims to summarize the origin,development,principle,and future direction of rTMS and introduce this neuro-stimulation therapy to relevant clinicians.