BACKGROUND Cancer patients often suffer from severe stress reactions psychologically,such as anxiety and depression.Prostate cancer(PC)is one of the common cancer types,with most patients diagnosed at advanced stages ...BACKGROUND Cancer patients often suffer from severe stress reactions psychologically,such as anxiety and depression.Prostate cancer(PC)is one of the common cancer types,with most patients diagnosed at advanced stages that cannot be treated by radical surgery and which are accompanied by complications such as bodily pain and bone metastasis.Therefore,attention should be given to the mental health status of PC patients as well as physical adverse events in the course of clinical treatment.AIM To analyze the risk factors leading to anxiety and depression in PC patients after castration and build a risk prediction model.METHODS A retrospective analysis was performed on the data of 120 PC cases treated in Xi'an People's Hospital between January 2019 and January 2022.The patient cohort was divided into a training group(n=84)and a validation group(n=36)at a ratio of 7:3.The patients’anxiety symptoms and depression levels were assessed 2 wk after surgery with the Self-Rating Anxiety Scale(SAS)and the Selfrating Depression Scale(SDS),respectively.Logistic regression was used to analyze the risk factors affecting negative mood,and a risk prediction model was constructed.RESULTS In the training group,35 patients and 37 patients had an SAS score and an SDS score greater than or equal to 50,respectively.Based on the scores,we further subclassified patients into two groups:a bad mood group(n=35)and an emotional stability group(n=49).Multivariate logistic regression analysis showed that marital status,castration scheme,and postoperative Visual Analogue Scale(VAS)score were independent risk factors affecting a patient's bad mood(P<0.05).In the training and validation groups,patients with adverse emotions exhibited significantly higher risk scores than emotionally stable patients(P<0.0001).The area under the curve(AUC)of the risk prediction model for predicting bad mood in the training group was 0.743,the specificity was 70.96%,and the sensitivity was 66.03%,while in the validation group,the AUC,specificity,and sensitivity were 0.755,66.67%,and 76.19%,respectively.The Hosmer-Lemeshow test showed aχ^(2) of 4.2856,a P value of 0.830,and a C-index of 0.773(0.692-0.854).The calibration curve revealed that the predicted curve was basically consistent with the actual curve,and the calibration curve showed that the prediction model had good discrimination and accuracy.Decision curve analysis showed that the model had a high net profit.CONCLUSION In PC patients,marital status,castration scheme,and postoperative pain(VAS)score are important factors affecting postoperative anxiety and depression.The logistic regression model can be used to successfully predict the risk of adverse psychological emotions.展开更多
Objective： Hepatocellular carcinoma （HCC） is a complex disease which associates with both environmental and genetic factors. The purpose of this study was to investigate whether the genetic polymorphisms of UDP-glu...Objective： Hepatocellular carcinoma （HCC） is a complex disease which associates with both environmental and genetic factors. The purpose of this study was to investigate whether the genetic polymorphisms of UDP-glucuronosyltransferase（UGT1A7）, an important phase II biotransformation enzyme, and X-ray repair cross-complementing group 1（XRCC1）, a pivotal DNA-repair gene, were related to the risk of HCC in Northeast China. Methods： One hundred and thirty six HCC patients and one hundred and thirty six frequency-matched controls were included in this hospital-based case-control study. Genotypes of UGT1A7 and XRCC1 were determined using allele-specific polymerase chain reaction （AS-PCR） and PCR-restriction fragment length polymorphism （RFLP）, and for which the odds ratio （OR） with 95% confidence interval （95% CI） were calculated. Results： The proportion of UGT1A7 low enzymatic allele （＊2 or ＊3） was higher in HCC patients than those in controls. The UGT1A7＊1/＊2 and ＊3/＊3 genotypes were associated with higher HCC risk （OR=2.09, 95%CI： 1.10-3.97; OR=5.67, 95%CI： 1.76-18.30, respectively）. The XRCC1 codon 399 Arg/Gln genotype could also elevate HCC risk （OR=2.16, 95% CI 1.29-3.61）. In addition to polymorphisms of UGT1A7 and XRCC1, multivariate logistic regression analysis demonstrated that other significant independent factors associated with HCC were HBV infection （OR=68.07, 95%CI： 28.03-165.26）, HCV infection （OR=30.97, 95%CI： 8.06-118.94） and family history of HCC （OR=10.62, 95%CI： 2.22-50.77）. Conclusion： The study shows that the polymorphisms of UGT1A7 and XRCC1 are associated with HCC risk. Determination of the polymorphisms of UGT1A7 and XRCC1 may provide an important clue to preventive measure against HCC.展开更多
Objective:This study aimed to identify microRNAs(miRNAs)involved in the development of perioperative neurocognitive disorders(PND).Methods:Plasma exosomal miRNA expression was examined in patients before and after car...Objective:This study aimed to identify microRNAs(miRNAs)involved in the development of perioperative neurocognitive disorders(PND).Methods:Plasma exosomal miRNA expression was examined in patients before and after cardiopulmonary bypass(CPB)using microarray and qRT-PCR and these patients were diagnosed as PND later.Elderly rats were subjected to CPB,and the cognitive functions were examined.Bioinformatics analysis was conducted to predict the targets of miR-214-3p.Rats were administered rno-miR-214-3p agomir before or after CPB to investigate the role of miR-214-3p in PND development.Results:We identified 76 differentially expressed plasma exosomal miRNAs in PND patients after surgery(P<0.05,|log2FC|>0.58),including the upregulated hsa-miR-214-3p(P=0.002399392).Prostaglandin-endoperoxide synthase 2(PTGS2)was predicted as a miR-214-3p target.In rats,CPB reduced the platform crossing numbers and target quadrant stay time,accompanied with hippocampal neuronal necrosis.The rno-miR-214-3p level was significantly increased in plasma exosomes but decreased in rat hippocampus after surgery,exhibiting a negative correlation(P<0.001,r=-0.762).A negative correlation between miR-214-3p and PTGS2 protein expression was also observed in the hippocampus after surgery.Importantly,rno-miR-214-3p agomir treatment,before or after surgery,significantly increased the platform crossing numbers(P=0.035)and target quadrant stay time(P=0.029)compared with negative control.Hippocampal PTGS2 protein level was increased in the untreated surgery group and decreased in response to rno-miR-214-3p agomir treatment before or after surgery(both P<0.05 vs.negative control).Conclusion:These data suggest that miR-214-3p/PTGS2 signaling contributes to the development of PND,serving as a potential therapeutic target for PND.展开更多
Objective To investigate the ultrasonic detection probability, type, prenatal diagnosis, and outcome of congenital cystic adenomatoid malformation of lung （CCAM）. Methods In this retrospective study, all 12 cases wh...Objective To investigate the ultrasonic detection probability, type, prenatal diagnosis, and outcome of congenital cystic adenomatoid malformation of lung （CCAM）. Methods In this retrospective study, all 12 cases which were diagnosed with suspected prenatal CC,4M over the period in the hospital were analyzed. Information on diagnosis time, types and progression of the lesions during pregnancy, the additional abnormalities, and the outcome of pregnancies were recorded.Results The positive rate of ultrasonic detection of CCAM was about 1.01‰ （1/11 124） before 28 gestation weeks. There were 1 case of type Ⅰ （8%）, 2 cases of type Ⅱ （17%） and 9 cases of type Ⅲ （75%）. Nine pregnancies were terminated and 2 cases were confirmed by pathology. Three neonates were alive and without any symptom now. Conclusions Type Ⅲ is the major type. Ultrasound examination during 20-28 weeks and following up, prenatal consultation, chromosome examination offetus, delivery with a pediatrician standing by, and all suspected neonates being investigated are recommended.展开更多
Objective Abnormal QT prolongation associated with arrhythmias is considered the major cardiac electrical disorder and a significant predictor of mortality in diabetic patients. The precise ionic mechanisms for diabet...Objective Abnormal QT prolongation associated with arrhythmias is considered the major cardiac electrical disorder and a significant predictor of mortality in diabetic patients. The precise ionic mechanisms for diabetic QT prolongation remained unclear. The present study was designed to analyze the changes of ventricular repolarization and the underlying ionic mechanisms in diabetic rabbit hearts. Methods Diabetes was induced by a single injection ofalloxan （145mg/kg, Lv. ）. After the development of diabetes （10 weeks）, ECG was measured. Whole-cell patch-clamp technique was applied to record the action potential duration （APD50, APD90）, slowly activating outward rectifying potassium current （IKs）, L-type calcium current （ICa-L） and inward rectifying potassium current （IK1）. Results The action potential duration （APD50 and APD90） of ventricular myocytes was obviously prolonged from 271.5＋32.3 ms and 347.8＋36.3 ms to 556.6~72.5 ms and 647.9~72.2 ms respectively （P〈 0.05）. Meanwhile the normalized peak current densities of IKs in ventricular myocytes investigated by whole-cell patch clamp was smaller in diabetic rabbits than that in control group at test potential of＋50mV （1.27~0.20 pA/pF vs 3.08~0.67 pA/pF, P〈0.05）. And the density of the ICa-L was increased apparently at the test potential of 10 mV （-2.67~0.41 pA/pF vs -5.404-1.08 pA/pF, P〈0.05）. Conclusion Ventricular repolarization was prolonged in diabetic rabbits, it may be partly due to the increased L-type calcium current and reduced slow delayed rectifier K＋ current （IKs） （J Geriatr Cardio12010; 7：25-29）.展开更多
Objective： It is known that chronic hepatitis B virus （HBV） infection is a main risk factor for hepatocellular carcinoma （HCC）. To assess the effect of HBV infection and its interaction with other factors on the ...Objective： It is known that chronic hepatitis B virus （HBV） infection is a main risk factor for hepatocellular carcinoma （HCC）. To assess the effect of HBV infection and its interaction with other factors on the risk for HCC, a hospital-based case-control study was carried out in Northeast China. Methods： A total of 384 cases with hepatocellular carcinoma and 432 controls without evidence of liver diseases were enrolled in the study. Blood samples were collected to detect the serum markers of hepatitis B virus （HBV） and hepatitis C virus （HCV） and questionnaires about lifestyle and family tumor history were performed in all subjects. Results： The total infection rate of HBV in hepatocellular carcinoma cases was 70.8% and 10.0% in non-liver disease controls. There was a statistically significant difference （P〈0.0001） between cases and controls （OR= 22.0; 95%CI：15.0-32.3）. Interaction analysis indicated that in HBV chronic carriers with HCV infection or alcohol consumption or family HCC history, the risk for HCC increased （OR=41.1, 95%CI： 20.2-83.9, OR=125.0, 95%CI： 66.5-235.2; OR=56.9, 95%CI： 27.2-119.3 respectively）. In addition, hepatitis B history, HCV infection, hepatic cirrhosis and family history of HCC were also potential HCC independent risk factors. Conclusion： We confirmed that HBV is a chief risk factor for hepatocellular carcinoma and accounts for 67.7% of all hepatocellular carcinoma in Northeast China. HCV infection, alcohol intake and family history could enhance the risk for HCC in chronic HBV carriers.展开更多
Molecular dynamics simulation is performed to characterize the concentration fluctuation of FeCu melts during the liquid-liquid phase separation process, which undergoes the following stages： the formation of interco...Molecular dynamics simulation is performed to characterize the concentration fluctuation of FeCu melts during the liquid-liquid phase separation process, which undergoes the following stages： the formation of interconnected structure and its coarsening, migration and coagulation of droplets driven by the decreasing of potential energy. The up-hill diffusion happens at the early relaxation period in which Cu atoms in Fe-rich region are forced to move toward Cu-rich region by spinodal decomposition with 90~ Cu content in Cu-rich region and 95~o Fe content in Fe-rich region at temperature of 1500K. The higher diffusion rate of homogeneous atom can be observed at lower temperature, which is attributed to the larger potential energy difference between Cu-rich region and Fe-rich region. It also exhibits energy heterogeneity in the separated liquid. The domain size decreases sharply during the aggregation and coarsening of droplets, after that it keeps unchanged until the coagulation of droplets begins. The studies characterize concentration and energy heterogeneity of phase-separated liquid on the atomic scale.展开更多
Pre-existing（multiple）shear bands were introduced into the ductile Zr56Co28Al16 and Zr65Ni10Cu15Al10bulk metallic glasses（BMGs）through the lateral-deformation,respectively.It was found that the pre-exiting shear b...Pre-existing（multiple）shear bands were introduced into the ductile Zr56Co28Al16 and Zr65Ni10Cu15Al10bulk metallic glasses（BMGs）through the lateral-deformation,respectively.It was found that the pre-exiting shear bands can further enhance the compressive plasticity of ductile BMGs.According to the serration analysis on the plastic deformation of the as-cast and the pre-deformed samples,the serration events in the stress-strain curves during deformation display a self-organized critical（SOC）behavior.Compared with the as-cast BMGs,a larger power-law scaling exponent calculated based on serrated flow behaviors becomes larger for the pre-deformed BMGs,implying that the shear banding stability of BMGs is effectively enhanced.This should be caused by the pronounced interactions of shear bands during plastic deformation for the pre-deformed BMGs.However,by introducing a large amount of multiple shear bands into the glassy matrix,it also becomes easier for shear bands to propagate along the pre-existing shear bands,leading to a lower cut-off elastic energy density for the pre-deformed BMGs.More multiple shear bands with stronger interactions for the pre-deformed BMGs could provide a larger chance to activate the shear-band cracking but less local elastic energies are remained for the subsequent crack-linking.展开更多
文摘BACKGROUND Cancer patients often suffer from severe stress reactions psychologically,such as anxiety and depression.Prostate cancer(PC)is one of the common cancer types,with most patients diagnosed at advanced stages that cannot be treated by radical surgery and which are accompanied by complications such as bodily pain and bone metastasis.Therefore,attention should be given to the mental health status of PC patients as well as physical adverse events in the course of clinical treatment.AIM To analyze the risk factors leading to anxiety and depression in PC patients after castration and build a risk prediction model.METHODS A retrospective analysis was performed on the data of 120 PC cases treated in Xi'an People's Hospital between January 2019 and January 2022.The patient cohort was divided into a training group(n=84)and a validation group(n=36)at a ratio of 7:3.The patients’anxiety symptoms and depression levels were assessed 2 wk after surgery with the Self-Rating Anxiety Scale(SAS)and the Selfrating Depression Scale(SDS),respectively.Logistic regression was used to analyze the risk factors affecting negative mood,and a risk prediction model was constructed.RESULTS In the training group,35 patients and 37 patients had an SAS score and an SDS score greater than or equal to 50,respectively.Based on the scores,we further subclassified patients into two groups:a bad mood group(n=35)and an emotional stability group(n=49).Multivariate logistic regression analysis showed that marital status,castration scheme,and postoperative Visual Analogue Scale(VAS)score were independent risk factors affecting a patient's bad mood(P<0.05).In the training and validation groups,patients with adverse emotions exhibited significantly higher risk scores than emotionally stable patients(P<0.0001).The area under the curve(AUC)of the risk prediction model for predicting bad mood in the training group was 0.743,the specificity was 70.96%,and the sensitivity was 66.03%,while in the validation group,the AUC,specificity,and sensitivity were 0.755,66.67%,and 76.19%,respectively.The Hosmer-Lemeshow test showed aχ^(2) of 4.2856,a P value of 0.830,and a C-index of 0.773(0.692-0.854).The calibration curve revealed that the predicted curve was basically consistent with the actual curve,and the calibration curve showed that the prediction model had good discrimination and accuracy.Decision curve analysis showed that the model had a high net profit.CONCLUSION In PC patients,marital status,castration scheme,and postoperative pain(VAS)score are important factors affecting postoperative anxiety and depression.The logistic regression model can be used to successfully predict the risk of adverse psychological emotions.
基金supported by the grant from Department of Education of Liaoning Province, China (No. 2008S232)
文摘Objective： Hepatocellular carcinoma （HCC） is a complex disease which associates with both environmental and genetic factors. The purpose of this study was to investigate whether the genetic polymorphisms of UDP-glucuronosyltransferase（UGT1A7）, an important phase II biotransformation enzyme, and X-ray repair cross-complementing group 1（XRCC1）, a pivotal DNA-repair gene, were related to the risk of HCC in Northeast China. Methods： One hundred and thirty six HCC patients and one hundred and thirty six frequency-matched controls were included in this hospital-based case-control study. Genotypes of UGT1A7 and XRCC1 were determined using allele-specific polymerase chain reaction （AS-PCR） and PCR-restriction fragment length polymorphism （RFLP）, and for which the odds ratio （OR） with 95% confidence interval （95% CI） were calculated. Results： The proportion of UGT1A7 low enzymatic allele （＊2 or ＊3） was higher in HCC patients than those in controls. The UGT1A7＊1/＊2 and ＊3/＊3 genotypes were associated with higher HCC risk （OR=2.09, 95%CI： 1.10-3.97; OR=5.67, 95%CI： 1.76-18.30, respectively）. The XRCC1 codon 399 Arg/Gln genotype could also elevate HCC risk （OR=2.16, 95% CI 1.29-3.61）. In addition to polymorphisms of UGT1A7 and XRCC1, multivariate logistic regression analysis demonstrated that other significant independent factors associated with HCC were HBV infection （OR=68.07, 95%CI： 28.03-165.26）, HCV infection （OR=30.97, 95%CI： 8.06-118.94） and family history of HCC （OR=10.62, 95%CI： 2.22-50.77）. Conclusion： The study shows that the polymorphisms of UGT1A7 and XRCC1 are associated with HCC risk. Determination of the polymorphisms of UGT1A7 and XRCC1 may provide an important clue to preventive measure against HCC.
基金supported by grantsfrom the Department of Human Resources and Social Security of Sichuan Province(No.19058)the subject of Health Commission of Sichuan Province(No.20PJ130)+2 种基金the Science and Technology Strategic Cooperation Programs of Luzhou Municipal People's Government and Southwest Medical University(No.2019LZXNYDJ36)the subject of Affiliated Hospital of Southwest Medical University(No.2017-PT-45)the Doctoral Research Initiation Fund of Affiliated Hospital of Southwest Medical University(No.19023).
文摘Objective:This study aimed to identify microRNAs(miRNAs)involved in the development of perioperative neurocognitive disorders(PND).Methods:Plasma exosomal miRNA expression was examined in patients before and after cardiopulmonary bypass(CPB)using microarray and qRT-PCR and these patients were diagnosed as PND later.Elderly rats were subjected to CPB,and the cognitive functions were examined.Bioinformatics analysis was conducted to predict the targets of miR-214-3p.Rats were administered rno-miR-214-3p agomir before or after CPB to investigate the role of miR-214-3p in PND development.Results:We identified 76 differentially expressed plasma exosomal miRNAs in PND patients after surgery(P<0.05,|log2FC|>0.58),including the upregulated hsa-miR-214-3p(P=0.002399392).Prostaglandin-endoperoxide synthase 2(PTGS2)was predicted as a miR-214-3p target.In rats,CPB reduced the platform crossing numbers and target quadrant stay time,accompanied with hippocampal neuronal necrosis.The rno-miR-214-3p level was significantly increased in plasma exosomes but decreased in rat hippocampus after surgery,exhibiting a negative correlation(P<0.001,r=-0.762).A negative correlation between miR-214-3p and PTGS2 protein expression was also observed in the hippocampus after surgery.Importantly,rno-miR-214-3p agomir treatment,before or after surgery,significantly increased the platform crossing numbers(P=0.035)and target quadrant stay time(P=0.029)compared with negative control.Hippocampal PTGS2 protein level was increased in the untreated surgery group and decreased in response to rno-miR-214-3p agomir treatment before or after surgery(both P<0.05 vs.negative control).Conclusion:These data suggest that miR-214-3p/PTGS2 signaling contributes to the development of PND,serving as a potential therapeutic target for PND.
基金This study is supported by 2004-2006 important clinic studies of medical institutions belonging to the Health Care Ministry of China
文摘Objective To investigate the ultrasonic detection probability, type, prenatal diagnosis, and outcome of congenital cystic adenomatoid malformation of lung （CCAM）. Methods In this retrospective study, all 12 cases which were diagnosed with suspected prenatal CC,4M over the period in the hospital were analyzed. Information on diagnosis time, types and progression of the lesions during pregnancy, the additional abnormalities, and the outcome of pregnancies were recorded.Results The positive rate of ultrasonic detection of CCAM was about 1.01‰ （1/11 124） before 28 gestation weeks. There were 1 case of type Ⅰ （8%）, 2 cases of type Ⅱ （17%） and 9 cases of type Ⅲ （75%）. Nine pregnancies were terminated and 2 cases were confirmed by pathology. Three neonates were alive and without any symptom now. Conclusions Type Ⅲ is the major type. Ultrasound examination during 20-28 weeks and following up, prenatal consultation, chromosome examination offetus, delivery with a pediatrician standing by, and all suspected neonates being investigated are recommended.
基金This work was supported by the National Natural Science Foundation of China （30600253）, Min＆try of Edu- cation Key Project （207031） and Scientific Research Fundation for the Returned Chinese Scholars of Heilongjiang Province of China （LC07C20）.
文摘Objective Abnormal QT prolongation associated with arrhythmias is considered the major cardiac electrical disorder and a significant predictor of mortality in diabetic patients. The precise ionic mechanisms for diabetic QT prolongation remained unclear. The present study was designed to analyze the changes of ventricular repolarization and the underlying ionic mechanisms in diabetic rabbit hearts. Methods Diabetes was induced by a single injection ofalloxan （145mg/kg, Lv. ）. After the development of diabetes （10 weeks）, ECG was measured. Whole-cell patch-clamp technique was applied to record the action potential duration （APD50, APD90）, slowly activating outward rectifying potassium current （IKs）, L-type calcium current （ICa-L） and inward rectifying potassium current （IK1）. Results The action potential duration （APD50 and APD90） of ventricular myocytes was obviously prolonged from 271.5＋32.3 ms and 347.8＋36.3 ms to 556.6~72.5 ms and 647.9~72.2 ms respectively （P〈 0.05）. Meanwhile the normalized peak current densities of IKs in ventricular myocytes investigated by whole-cell patch clamp was smaller in diabetic rabbits than that in control group at test potential of＋50mV （1.27~0.20 pA/pF vs 3.08~0.67 pA/pF, P〈0.05）. And the density of the ICa-L was increased apparently at the test potential of 10 mV （-2.67~0.41 pA/pF vs -5.404-1.08 pA/pF, P〈0.05）. Conclusion Ventricular repolarization was prolonged in diabetic rabbits, it may be partly due to the increased L-type calcium current and reduced slow delayed rectifier K＋ current （IKs） （J Geriatr Cardio12010; 7：25-29）.
基金supported by grant from Department of Education of LaoningProvincia1(No.2008S232)
文摘Objective： It is known that chronic hepatitis B virus （HBV） infection is a main risk factor for hepatocellular carcinoma （HCC）. To assess the effect of HBV infection and its interaction with other factors on the risk for HCC, a hospital-based case-control study was carried out in Northeast China. Methods： A total of 384 cases with hepatocellular carcinoma and 432 controls without evidence of liver diseases were enrolled in the study. Blood samples were collected to detect the serum markers of hepatitis B virus （HBV） and hepatitis C virus （HCV） and questionnaires about lifestyle and family tumor history were performed in all subjects. Results： The total infection rate of HBV in hepatocellular carcinoma cases was 70.8% and 10.0% in non-liver disease controls. There was a statistically significant difference （P〈0.0001） between cases and controls （OR= 22.0; 95%CI：15.0-32.3）. Interaction analysis indicated that in HBV chronic carriers with HCV infection or alcohol consumption or family HCC history, the risk for HCC increased （OR=41.1, 95%CI： 20.2-83.9, OR=125.0, 95%CI： 66.5-235.2; OR=56.9, 95%CI： 27.2-119.3 respectively）. In addition, hepatitis B history, HCV infection, hepatic cirrhosis and family history of HCC were also potential HCC independent risk factors. Conclusion： We confirmed that HBV is a chief risk factor for hepatocellular carcinoma and accounts for 67.7% of all hepatocellular carcinoma in Northeast China. HCV infection, alcohol intake and family history could enhance the risk for HCC in chronic HBV carriers.
基金Supported by the National Natural Science Foundation of China under Grant No 51371108,51501104 and 51501103
文摘Molecular dynamics simulation is performed to characterize the concentration fluctuation of FeCu melts during the liquid-liquid phase separation process, which undergoes the following stages： the formation of interconnected structure and its coarsening, migration and coagulation of droplets driven by the decreasing of potential energy. The up-hill diffusion happens at the early relaxation period in which Cu atoms in Fe-rich region are forced to move toward Cu-rich region by spinodal decomposition with 90~ Cu content in Cu-rich region and 95~o Fe content in Fe-rich region at temperature of 1500K. The higher diffusion rate of homogeneous atom can be observed at lower temperature, which is attributed to the larger potential energy difference between Cu-rich region and Fe-rich region. It also exhibits energy heterogeneity in the separated liquid. The domain size decreases sharply during the aggregation and coarsening of droplets, after that it keeps unchanged until the coagulation of droplets begins. The studies characterize concentration and energy heterogeneity of phase-separated liquid on the atomic scale.
基金financially supported by the National Natural Science Foundation of China(51501104,51501103,and 51371108)the Young Scholars Program of Shandong University(Weihai)
文摘Pre-existing（multiple）shear bands were introduced into the ductile Zr56Co28Al16 and Zr65Ni10Cu15Al10bulk metallic glasses（BMGs）through the lateral-deformation,respectively.It was found that the pre-exiting shear bands can further enhance the compressive plasticity of ductile BMGs.According to the serration analysis on the plastic deformation of the as-cast and the pre-deformed samples,the serration events in the stress-strain curves during deformation display a self-organized critical（SOC）behavior.Compared with the as-cast BMGs,a larger power-law scaling exponent calculated based on serrated flow behaviors becomes larger for the pre-deformed BMGs,implying that the shear banding stability of BMGs is effectively enhanced.This should be caused by the pronounced interactions of shear bands during plastic deformation for the pre-deformed BMGs.However,by introducing a large amount of multiple shear bands into the glassy matrix,it also becomes easier for shear bands to propagate along the pre-existing shear bands,leading to a lower cut-off elastic energy density for the pre-deformed BMGs.More multiple shear bands with stronger interactions for the pre-deformed BMGs could provide a larger chance to activate the shear-band cracking but less local elastic energies are remained for the subsequent crack-linking.
