The paper attempts to represent a case of repeated failures on a high cut slope due to multi-excavation. The characteristics of each failure induced by excavation are analyzed through geological investigation, and the...The paper attempts to represent a case of repeated failures on a high cut slope due to multi-excavation. The characteristics of each failure induced by excavation are analyzed through geological investigation, and then a geological model at different failure stages is proposed. The geological analysis shows that the excavation-induced repeated failures are related to the exposure of the weak bedding plane and the toe unloading of the cut slope, Numerical modeling is conducted based on a sequential method, taking into account the main failure stages of cut slope. The simulation results fairly coincide with the practical phenomena observed in field. It is shown that the decrease in normal stress of displaced mass on cut slope will induce the increase in shear stress in bedding planes and that at the toe of the cut slope. The released stress leads to repeated gravitational instabilities of cut slope due to the decrease in normal stress and the increase in shear stress along the bedding planes of mudstone.展开更多
Long-term gonadotropin-releasing hormone agonist（Gn RHa） administration before in vitro fertilization（IVF）/intracytoplasmic sperm injection（ICSI） in infertile women with endometriosis or adenomyosis significantl...Long-term gonadotropin-releasing hormone agonist（Gn RHa） administration before in vitro fertilization（IVF）/intracytoplasmic sperm injection（ICSI） in infertile women with endometriosis or adenomyosis significantly enhanced the chances of pregnancy in both fresh and frozen embryo transfer cycles. We hypothesized that long-term Gn RHa treatment might also be beneficial for the idiopathic repeated implantation failure（RIF） patients. In the 21 patients receiving Gn RHa and hormone replacement therapy（G-HRT） protocols for frozen embryo transfer, their data were compared with those of the 56 of frozen/fresh cycles they had previously undergone（previous protocols）. Comparison showed that the finial results were significantly better with G-HRT protocols than with their previous protocols, with pregnancy rate, clinical pregnancy rate, implantation rate and on-going pregnancy rate being 70%, 60%, 40% and 38% respectively with G-HRT protocols, against 17%, 11%, 6.3% and 5% with previous protocols. The results showed that hormonally controlled endometrial preparation with prior Gn RHa suppression could be used for patients who had experienced repeated failures of IVF treatment despite having morphologically optimal embryos, and the treatment may help increase the receptivity of the endometrium in these patients.展开更多
Using self-made impact fatigue test instruments and related analytic devices,the mechanical components with laser cladding layer have been attempted. It is found that, onrepeated impact force, several failure modes of...Using self-made impact fatigue test instruments and related analytic devices,the mechanical components with laser cladding layer have been attempted. It is found that, onrepeated impact force, several failure modes of the components include the surface cracks, surfaceplastic deformation, corrosive pitting and coat collapse, etc. The paper reported the test methodand initial analysis conclusions about the unique failure characteristics of the mechanicalcomponents on repeated impact load.展开更多
Objective\ The relationship between graft blood flow, epicardial microflow, mean arterial pressure and hemorheologic changes was studied during intraoperative heart failure. Methods\ These parameters were done to ...Objective\ The relationship between graft blood flow, epicardial microflow, mean arterial pressure and hemorheologic changes was studied during intraoperative heart failure. Methods\ These parameters were done to evaluate the use of repeated cardiopulmonary bypass support for the intraoperative heart failure following aorto coronary bypass surgery. Included in this study were 10 patients with a mean age of 70 and unstable angina undergoing coronary bypass grafting and suffering from intraoperative heart failure. The epicardiai microflow, graft flow, mean arterial pressure and blood cell filterability were measured. Resluts\ During heart failure, the mean arterial pressure fell by 41%(P<0.01), graft flow by 67%(P<0.01) and epicardialmicroflow by 64%(P<0.01). After 15 to 56 min of assisted cardiopulmonary bypass support, the epicardial microflow and graft flow were partially restored, while red cell and white cell filterability was reduced by 31% and 64% respectively (P<0.01). There were significant correlations between graft flow, epicardial microflow, blood cell filterability and cardiopulmonary bypass time. All patients recovered and were discharged from the hospital.Conclusion\ It is concluded that the use of temporary assisted CPB support to treat intrapoperative heart failure allows the recovery of the myocardium and thereby restores the mean arterial pressure. The recovery of graft flow and epicardial flow occurred to a lesser extent. The CPB support seemed to be suitable for about 60 min probably because of increasing disturbance to the blood cell filterability, graft flow and the epicardial microcirculation.\;展开更多
Objective:The objective of this study was to investigate the clinical value of the endometrial microbiota test(EMT)combined with personalized treatment in patients with repeated implantation failure(RIF).Methods:From ...Objective:The objective of this study was to investigate the clinical value of the endometrial microbiota test(EMT)combined with personalized treatment in patients with repeated implantation failure(RIF).Methods:From March 2019 to August 2022,the clinical data of patients with RIF at the Reproductive Medicine Research Center of the Sixth Affiliated Hospital of Sun Yat-sen University were retrospectively analyzed.A total of 356 patients underwent the EMT using 16S rRNA sequencing and were included in the EMT group.The SPSS statistical software propensity score was set at 1:1 to match the age,anti-Müllerian hormone(AMH),antral follicle count(AFC),years of infertility,and body mass index(BMI)of the women who had not undergone the EMT;subsequently,354 patients were classified in the non-EMT group.We compared the clinical characteristics of the two groups and analyzed the clinical pregnancy outcomes after personalized treatment.Results:The clinical pregnancy rate(CPR)of the EMT group was significantly higher than that of the non-EMT group(47.81%vs.13.38%,P<0.05).Among 356 patients who underwent the EMT,55 patients(15.45%)in group A with normal endometrial microbiota composition did not test positive for the pathogenic bacteria causing chronic endometritis,34 patients(9.55%)in group B with abnormal endometrial microbiota composition did not test positive for the pathogenic bacteria causing chronic endometritis,35 patients(9.83%)in group C with normal endometrial microbiota composition tested positive for the pathogenic bacteria causing chronic endometritis,and 232 patients(65.17%)in group D with abnormal endometrial microbiota composition tested positive for the pathogenic bacteria causing chronic endometritis.After administration of probiotics or antibiotic plus probiotics treatment,the pregnancy rates of groups C and D were higher than those of group A(44.00%vs.20.00%and 55.03%vs.20.00%,respectively;bothP<0.05).Conclusion:The EMT combined with personalized treatment in patients with RIF has solid clinical value as a new treatment strategy.展开更多
OBJECTIVE:To explore the therapeutic efficacy of acupuncture treatment on repeated implantation failure(RIF)patients with cryo-thawed embryo transfer(CET).METHODS:In a retrospective cohort study,all eligible women und...OBJECTIVE:To explore the therapeutic efficacy of acupuncture treatment on repeated implantation failure(RIF)patients with cryo-thawed embryo transfer(CET).METHODS:In a retrospective cohort study,all eligible women undergoing RIF were recruited in our center from January 1,2018 to December 31,2021.The patients were grouped by whether an acceptance of acupuncture treatment before CET,including the acupuncture group(Acu-group,55 cycles)and control group(Con-group,244 cycles).Data were analyzed by using binary logistic regression to explore the relationship of acupuncture treatment with pregnancy outcomes.RESULTS:The Acu-group had higher live-birth rate(LBR)[54.5%vs 41.0%,respectively;odds ratio(OR)=1.105,95%confidence interval(CI)(1.029,1.187),P=0.006]and ongoing pregnancy rate(OPR)[56.4%vs 43.0%,respectively;OR=1.100,95%CI(1.025,1.181),P=0.008]than the Con-group.There were no significant between-group differences in the rates of implantation[OR=1.070,95%CI(0.996,1.149),P=0.064],clinical pregnancy[OR=1.065,95%CI(0.997,1.138),P=0.061],biochemical pregnancy[OR=1.002,95%CI(0.903,1.112),P=0.967],or miscarriage[OR=0.778,95%CI(0.551,1.099),P=0.155].Perinatal outcomes did not differ significantly between the two groups.CONCLUSIONS:Acupuncture treatment could improve the LBR and OPR in RIF patients with CET cycles,suggesting a potential adjuvant therapy of acupuncture to improve the pregnancy outcomes in RIF patients.展开更多
Often in longitudinal studies, some subjects complete their follow-up visits, but others miss their visits due to various reasons. For those who miss follow-up visits, some of them might learn that the event of intere...Often in longitudinal studies, some subjects complete their follow-up visits, but others miss their visits due to various reasons. For those who miss follow-up visits, some of them might learn that the event of interest has already happened when they come back. In this case, not only are their event times interval-censored, but also their time-dependent measurements are incomplete. This problem was motivated by a national longitudinal survey of youth data. Maximum likelihood estimation (MLE) method based on expectation-maximization (EM) algorithm is used for parameter estimation. Then missing information principle is applied to estimate the variance-covariance matrix of the MLEs. Simulation studies demonstrate that the proposed method works well in terms of bias, standard error, and power for samples of moderate size. The national longitudinal survey of youth 1997 (NLSY97) data is analyzed for illustration.展开更多
基金Supported by the National Natural Science Foundation of China(41072213 and 40801212)the Opening Fund of Key Laboratory of Mechanics on Disaster and Environment in Western China, Lanzhou University(201207)
文摘The paper attempts to represent a case of repeated failures on a high cut slope due to multi-excavation. The characteristics of each failure induced by excavation are analyzed through geological investigation, and then a geological model at different failure stages is proposed. The geological analysis shows that the excavation-induced repeated failures are related to the exposure of the weak bedding plane and the toe unloading of the cut slope, Numerical modeling is conducted based on a sequential method, taking into account the main failure stages of cut slope. The simulation results fairly coincide with the practical phenomena observed in field. It is shown that the decrease in normal stress of displaced mass on cut slope will induce the increase in shear stress in bedding planes and that at the toe of the cut slope. The released stress leads to repeated gravitational instabilities of cut slope due to the decrease in normal stress and the increase in shear stress along the bedding planes of mudstone.
基金supported by grants from the National Natural Science Foundation of China(No.81100401 and No.81470063)Guangdong Natural Science Foundation of China(No.2014A030313129)the Doctoral Fund of the Ministry of Education of China(No.20110171120096)
文摘Long-term gonadotropin-releasing hormone agonist（Gn RHa） administration before in vitro fertilization（IVF）/intracytoplasmic sperm injection（ICSI） in infertile women with endometriosis or adenomyosis significantly enhanced the chances of pregnancy in both fresh and frozen embryo transfer cycles. We hypothesized that long-term Gn RHa treatment might also be beneficial for the idiopathic repeated implantation failure（RIF） patients. In the 21 patients receiving Gn RHa and hormone replacement therapy（G-HRT） protocols for frozen embryo transfer, their data were compared with those of the 56 of frozen/fresh cycles they had previously undergone（previous protocols）. Comparison showed that the finial results were significantly better with G-HRT protocols than with their previous protocols, with pregnancy rate, clinical pregnancy rate, implantation rate and on-going pregnancy rate being 70%, 60%, 40% and 38% respectively with G-HRT protocols, against 17%, 11%, 6.3% and 5% with previous protocols. The results showed that hormonally controlled endometrial preparation with prior Gn RHa suppression could be used for patients who had experienced repeated failures of IVF treatment despite having morphologically optimal embryos, and the treatment may help increase the receptivity of the endometrium in these patients.
文摘Using self-made impact fatigue test instruments and related analytic devices,the mechanical components with laser cladding layer have been attempted. It is found that, onrepeated impact force, several failure modes of the components include the surface cracks, surfaceplastic deformation, corrosive pitting and coat collapse, etc. The paper reported the test methodand initial analysis conclusions about the unique failure characteristics of the mechanicalcomponents on repeated impact load.
文摘Objective\ The relationship between graft blood flow, epicardial microflow, mean arterial pressure and hemorheologic changes was studied during intraoperative heart failure. Methods\ These parameters were done to evaluate the use of repeated cardiopulmonary bypass support for the intraoperative heart failure following aorto coronary bypass surgery. Included in this study were 10 patients with a mean age of 70 and unstable angina undergoing coronary bypass grafting and suffering from intraoperative heart failure. The epicardiai microflow, graft flow, mean arterial pressure and blood cell filterability were measured. Resluts\ During heart failure, the mean arterial pressure fell by 41%(P<0.01), graft flow by 67%(P<0.01) and epicardialmicroflow by 64%(P<0.01). After 15 to 56 min of assisted cardiopulmonary bypass support, the epicardial microflow and graft flow were partially restored, while red cell and white cell filterability was reduced by 31% and 64% respectively (P<0.01). There were significant correlations between graft flow, epicardial microflow, blood cell filterability and cardiopulmonary bypass time. All patients recovered and were discharged from the hospital.Conclusion\ It is concluded that the use of temporary assisted CPB support to treat intrapoperative heart failure allows the recovery of the myocardium and thereby restores the mean arterial pressure. The recovery of graft flow and epicardial flow occurred to a lesser extent. The CPB support seemed to be suitable for about 60 min probably because of increasing disturbance to the blood cell filterability, graft flow and the epicardial microcirculation.\;
文摘Objective:The objective of this study was to investigate the clinical value of the endometrial microbiota test(EMT)combined with personalized treatment in patients with repeated implantation failure(RIF).Methods:From March 2019 to August 2022,the clinical data of patients with RIF at the Reproductive Medicine Research Center of the Sixth Affiliated Hospital of Sun Yat-sen University were retrospectively analyzed.A total of 356 patients underwent the EMT using 16S rRNA sequencing and were included in the EMT group.The SPSS statistical software propensity score was set at 1:1 to match the age,anti-Müllerian hormone(AMH),antral follicle count(AFC),years of infertility,and body mass index(BMI)of the women who had not undergone the EMT;subsequently,354 patients were classified in the non-EMT group.We compared the clinical characteristics of the two groups and analyzed the clinical pregnancy outcomes after personalized treatment.Results:The clinical pregnancy rate(CPR)of the EMT group was significantly higher than that of the non-EMT group(47.81%vs.13.38%,P<0.05).Among 356 patients who underwent the EMT,55 patients(15.45%)in group A with normal endometrial microbiota composition did not test positive for the pathogenic bacteria causing chronic endometritis,34 patients(9.55%)in group B with abnormal endometrial microbiota composition did not test positive for the pathogenic bacteria causing chronic endometritis,35 patients(9.83%)in group C with normal endometrial microbiota composition tested positive for the pathogenic bacteria causing chronic endometritis,and 232 patients(65.17%)in group D with abnormal endometrial microbiota composition tested positive for the pathogenic bacteria causing chronic endometritis.After administration of probiotics or antibiotic plus probiotics treatment,the pregnancy rates of groups C and D were higher than those of group A(44.00%vs.20.00%and 55.03%vs.20.00%,respectively;bothP<0.05).Conclusion:The EMT combined with personalized treatment in patients with RIF has solid clinical value as a new treatment strategy.
文摘OBJECTIVE:To explore the therapeutic efficacy of acupuncture treatment on repeated implantation failure(RIF)patients with cryo-thawed embryo transfer(CET).METHODS:In a retrospective cohort study,all eligible women undergoing RIF were recruited in our center from January 1,2018 to December 31,2021.The patients were grouped by whether an acceptance of acupuncture treatment before CET,including the acupuncture group(Acu-group,55 cycles)and control group(Con-group,244 cycles).Data were analyzed by using binary logistic regression to explore the relationship of acupuncture treatment with pregnancy outcomes.RESULTS:The Acu-group had higher live-birth rate(LBR)[54.5%vs 41.0%,respectively;odds ratio(OR)=1.105,95%confidence interval(CI)(1.029,1.187),P=0.006]and ongoing pregnancy rate(OPR)[56.4%vs 43.0%,respectively;OR=1.100,95%CI(1.025,1.181),P=0.008]than the Con-group.There were no significant between-group differences in the rates of implantation[OR=1.070,95%CI(0.996,1.149),P=0.064],clinical pregnancy[OR=1.065,95%CI(0.997,1.138),P=0.061],biochemical pregnancy[OR=1.002,95%CI(0.903,1.112),P=0.967],or miscarriage[OR=0.778,95%CI(0.551,1.099),P=0.155].Perinatal outcomes did not differ significantly between the two groups.CONCLUSIONS:Acupuncture treatment could improve the LBR and OPR in RIF patients with CET cycles,suggesting a potential adjuvant therapy of acupuncture to improve the pregnancy outcomes in RIF patients.
文摘Often in longitudinal studies, some subjects complete their follow-up visits, but others miss their visits due to various reasons. For those who miss follow-up visits, some of them might learn that the event of interest has already happened when they come back. In this case, not only are their event times interval-censored, but also their time-dependent measurements are incomplete. This problem was motivated by a national longitudinal survey of youth data. Maximum likelihood estimation (MLE) method based on expectation-maximization (EM) algorithm is used for parameter estimation. Then missing information principle is applied to estimate the variance-covariance matrix of the MLEs. Simulation studies demonstrate that the proposed method works well in terms of bias, standard error, and power for samples of moderate size. The national longitudinal survey of youth 1997 (NLSY97) data is analyzed for illustration.
