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Artificial Cycle with or without a Depot Gonadotropin-releasing Hormone Agonist for Frozen-thawed Embryo Transfer: An Assessment of Infertility Type that Is Most Suitable 被引量:5
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作者 Di XIE Fan CHEN +4 位作者 Shou-zhen XIE Zhi-lan CHEN Ping TUO Rong ZHOU Juan ZHANG 《Current Medical Science》 SCIE CAS 2018年第4期626-631,共6页
The clinical outcomes of five groups of infertility patients receiving frozen- thawed, cleavage-stage embryo transfers with exogenous hormone protocols with or without a depot gonadotropin-releasing hormone (GnRH) a... The clinical outcomes of five groups of infertility patients receiving frozen- thawed, cleavage-stage embryo transfers with exogenous hormone protocols with or without a depot gonadotropin-releasing hormone (GnRH) agonist were assessed. A retrospective cohort analysis was performed on 1003 cycles undergoing frozen-thawed, cleavage-stage embryo transfers from January 1, 2012 to June 31, 2015 in the Reproductive Medicine Center of Wuhan General Hospital of Guangzhou Military Region. Based on the infertility etiologies of the patients, the 1003 cycles were divided into five groups: tubal infertility, polycystic ovary syndrome (PCOS), endometriosis, male infertility, and unexplained infertility. The main outcome was the live birth rate. Two groups were set up based on the intervention: group A was given a GnRH agonist with exogenous estrogen and progesterone, and group B (control group) was given exogenous estrogen and progesterone only. The results showed that the baseline serum hormone levels and basic characteristics of the patients were not significantly different between groups A and B. The live birth rates in groups A and B were 41.67% and 29.29%, respectively (P〈0.05). The live birth rates in patients with PCOS in groups A and B were 56.25% and 30.61%, respectively (P〈0.05). The clinical pregnancy, implantation and on-going pregnancy rates showed the same trends as the live birth rates between groups A and B. The ectopic pregnancy rate was significantly lower in group A than in group B. We concluded that the live birth rate was higher and other clinical outcomes were more satisfactory with GnRH agonist co- treatment than without GnRH agonist co-treatment for frozen-thawed embryo transfer. The GnRH agonist combined with exogenous estrogen and progesterone worked for all types of infertility tested, especially for women with PCOS. 展开更多
关键词 frozen-thawed embryo transfer gonadotropin-releasing hormone agonist polycystic ovary syndrome
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High-quality Cleavage Embryo versus Low-quality Blastocyst in Frozen-thawed Cycles:Comparison of Clinical Outcomes 被引量:3
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作者 Yu-lan WEI Bo HUANG +1 位作者 Xin-ling REN Lei JIN 《Current Medical Science》 SCIE CAS 2020年第5期968-972,共5页
This study compared the clinical outcomes of the frozen-thawed cycles of high-quality cleavage embryos with low-quality blastocysts to provide a reference for the choice of frozen-thawed embryo transfer schemes and to... This study compared the clinical outcomes of the frozen-thawed cycles of high-quality cleavage embryos with low-quality blastocysts to provide a reference for the choice of frozen-thawed embryo transfer schemes and to improve clinical pregnancy rates.A retrospective analysis was performed on the clinical data of patients undergoing frozen-thawed embryo transfer at the Reproductive Medicine Center of Tongji Hospital of Tongji Medical College of Huazhong University of Science and Technology from 2016 to 2017.In total,845 cases were divided into a high-quality cleavage embryo group(group A)and a low-quality blastocyst group(group B).Each group was further divided into subgroups based on the number of transplants.Group A was categorized into two subgroups comprising of 94 cases in subgroup Al(1 high-quality 8-cell group)and 201 cases in subgroup A2(2 high-quality 8-cell group).Group B was divided into four subgroups consisting of 73 cases in subgroup B I(D53BC group),65 cases in subgroup B2(D54BC group),110 cases in subgroup B3(D63BC group),and 282 cases in subgroup B4(D64BC group).The pregnancy outcomes and neonatal outcomes between the groups were compared.The clinical pregnancy rates(56.72%and 60.00%)and live birth rates(47.76%and 46.15%)in subgroups A2 and B2 showed no significant differences,but these rates were significantly higher in subgroups A2 and B2 than in the rest subgroups(P<0.05).The multiple birth rate(26.32%)in the subgroup A2 was significantly higher than that in the rest subgroups(P<0.05).There were no statistically significant differences in the abortion rates among all groups(P>0.05).In terms of neonatal outcomes,there were no statistically significant differences in the proportion of premature births,sex ratios,and birth defects among the low-weight and gigantic infants(P>0.05).Transplanting two high-quality cleavage embryos during the frozen-thawed embryo transfer cycles could significantly increase clinical pregnancy rates and live birth rates,but at the same time,it also increased the risks of multiple births and complications to mothers and infants.The D54BC subgroup had the most significant advantages among all groups(P<0.05).The rest low-quality blastocysts had clinical outcomes similar to the single high-quality cleavage embryo group. 展开更多
关键词 high-quality cleavage embryos low-quality blastocysts frozen-thawed transplantation clinical outcomes
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Different endometrial preparation protocols yield similar pregnancy outcomes for frozen-thawed embryo transfer in patients with advanced endometriosis 被引量:3
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作者 Hai-yan GUO Yun WANG +6 位作者 Qiu-ju CHEN Wei-ran CHAI Li-hua SUN Ai AI Yong-lun FU Qi-feng LYU Yan-ping KUANG 《Journal of Reproduction and Contraception》 CSCD 2016年第1期1-11,共11页
Objective To explore the different endometrial preparation for frozen-thawed embryo transfer (FET) in women with advanced endometriosis (EMS). Methods The pregnancy outcomes of patients with advanced EMS (542 cyc... Objective To explore the different endometrial preparation for frozen-thawed embryo transfer (FET) in women with advanced endometriosis (EMS). Methods The pregnancy outcomes of patients with advanced EMS (542 cycles), who were prepared for FET, were retrospectively assessed. Included patients underwent a total of 233 FET cycles (180 patients) using natural cycle (NC), a total of 142 FET cycles (115 patients) using letrozole (LE) ovulation induction, and a total of 167 FET cycles (137 patients) using hormonal replacement treatment (HRT) for endometrial preparation.Results There were no significant diffenences in the clinical pregnancy rate (LE: 49.30%, NC: 50.21%, and HRT: 43.11~/o, P=0.343), the implantation rate (LE: 29.26%, NC: 36.03%, and HRT: 29.55%, P=0.084), and the live birth rate (LE: 38.02%, NC: 39.11%, and HR T." 35.33 %, P=O. 648) among the three groups. No statistically signifi- cant differences were observed in the ongoing pregnancy rate, the miscarriage rate, and the pregnancy complication rate. The single birth weight in patients using NC- FET was lower than that in patients using HRT-FET (P=0.044) and a higher twin birth weight in patients using LE-FET were observed compared with other groups (P=O. 022). The rate of birth weight 〈2 500 g was also higher in the NC-FET group than in other groups. No congenital birth defects were found in the three groups. Conclusion Different endometrial preparation protocols without ultra-long GnRH-a down-regulation for FET yield similar pregnancy outcomes in patients with EMS. A tailored endometrial preparation protocol should be recommended according to different patients' situation. 展开更多
关键词 clinical pregnancy outcomes endometrial preparation endometriosis (EMS) frozen-thawed embryo transfer (FET)
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Clomiphene Citrate as An Adjuvant to hMG Stimulation of the Ovaries in Mid-to-late Follicular Phase and Subsequently Pregnancy Outcome of Frozen-thawed Embryo Transfers 被引量:2
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作者 Yan KANG Qing-qing HONG +4 位作者 Wei-ran CHAI Yong-lun FU Ai AI Qiu-ju CHEN Yan-ping KUANG 《Journal of Reproduction and Contraception》 CAS 2013年第1期10-20,共11页
Objective To compare the results of a novel regimen of human menopausal gonadotrophin (hMG) in combination with clomiphene citrate (CC) in mid-to-late follicular phase with those of a short protocol of GnRH agoni... Objective To compare the results of a novel regimen of human menopausal gonadotrophin (hMG) in combination with clomiphene citrate (CC) in mid-to-late follicular phase with those of a short protocol of GnRH agonist (GnRHa) and hMG used for IVF. Methods In the retrospective study, 842 patients undergoing IVF were collected and classified into two groups: hMG in combination with CC in mid-to-late follicular phase (group A, n=319) and short protocol of GnRHa-hMG (group B, n=523). The main outcome measures were ovarian responses in stimulation cycles and pregnancy outcomes in subsequent frozen-thawed embryo transfer (FET) cycles. Results In group A, the serum LH concentration on day 8 -10 was similar with that on the day of hCG administration (2.43 ± 1.92 IU vs 2.51 ±2.05 IU). The number of mature follicles and oocytes retrieved was significantly lower in group A than in group B while the fertilization rate and the cleavage rate were comparable. The clinical pregnancy rate (47. 79% vs 48.04%), the implantation rate (32.49% vs 33.11%) and the cumulative pregnancy rate (58.09% vs 60.22%) were respectively similar in group A and group B. Conclusion hMG in combination with CC in mid-to-late follicular phase results in the same pregnancy outcome as short protocol. The novel protocol may take the advantage of eliminating the occurrehce of a premature endogenous LH Surge. 展开更多
关键词 clomiphene citrate (CC) human menopausal gonadotrophin (hMG) frozen-thawed embryo transfer (FET) short protocol
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Pregnancy Outcomes for Day 5 Versus Day 6 Single Frozen-thawed Blastocyst Transfer with Different Qualities of Embryos: A Large Matched-cohort Study 被引量:1
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作者 Qiong YU Hui HE +2 位作者 Xin-ling REN Shi-fu HU Lei JIN 《Current Medical Science》 SCIE CAS 2023年第2期297-303,共7页
Objective This study aimed to determine whether the day of blastocyst expansion affects pregnancy outcomes in frozen-thawed blastocyst transfer(FBT)cycles.Methods A retrospective match-cohort study was conducted.Patie... Objective This study aimed to determine whether the day of blastocyst expansion affects pregnancy outcomes in frozen-thawed blastocyst transfer(FBT)cycles.Methods A retrospective match-cohort study was conducted.Patients who underwent blastocyst transfer in frozen-thawed cycles at day 5 or 6 were matched for potential confounding factors.A total of 2207 matched pairs of FBT cycles were included from January 2016 to December 2019 in our Reproductive Medicine Center.Results The clinical pregnancy rate(CPR)and live birth rate(LBR)were significantly increased in day 5 blastocyst transfers when compared to day 6 blastocyst transfers,in terms of the same embryo quality.For FBT cycles with good-quality embryo,the CPR at day 5 and 6 was 61.30%and 57.56%,respectively(P=0.045),and the LBR was 44.79%and 36.16%,respectively(P<0.001).For FBT cycles with poor-quality embryo,the CPR at day 5 and 6 was 48.61%and 40.89%,respectively(P=0.006),and the LBR was 31.71%and 25.74%,respectively(P=0.019).The CPR for FBT cycles with good-quality embryo was statistically higher at day 6 than that at day 5 with poor-quality embryo transferred(57.56%vs.48.61%,P=0.001).Maternal age,anti-Müllerian hormone(AMH),endometrial thickness,embryo quality,and the day of blastocyst expansion were independently correlated with the CPR and LBR.The FBT cycles at day 5 had significantly higher CPR(adjusted odds ratio[OR]=1.246,95%confidence intervals[CI]:1.097–1.415,P=0.001)and LBR(adjusted OR=1.435,95%CI:1.258–1.637,P<0.001)than those at day 6.Conclusion The embryo quality is the primary indicator for FBT cycles.Day 5 blastocysts should be preferred when the quality of embryo at day 5 is the same as that at day 6. 展开更多
关键词 frozen-thawed blastocyst transfer day 5 versus day 6 embryo quality clinical pregnancy rate live birth rate
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Embryo Transfer Strategies for Women with Recurrent Implantation Failure During the Frozen-thawed Embryo Transfer Cycles:Sequential Embryo Transfer or Double-blastocyst Transfer?
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作者 Qiao-hang ZHAO Yu-wei SONG +8 位作者 Jian CHEN Xiang ZHOU Ji-lai XIE Qiu-ping YAO Qi-yin DONG Chun FENG Li-ming ZHOU Wei-ping FU Min JIN 《Current Medical Science》 SCIE CAS 2024年第1期212-222,共11页
Objective Both sequential embryo transfer(SeET)and double-blastocyst transfer(DBT)can serve as embryo transfer strategies for women with recurrent implantation failure(RIF).This study aims to compare the effects of Se... Objective Both sequential embryo transfer(SeET)and double-blastocyst transfer(DBT)can serve as embryo transfer strategies for women with recurrent implantation failure(RIF).This study aims to compare the effects of SeET and DBT on pregnancy outcomes.Methods Totally,261 frozen-thawed embryo transfer cycles of 243 RIF women were included in this multicenter retrospective analysis.According to different embryo quality and transfer strategies,they were divided into four groups:group A,good-quality SeET(GQ-SeET,n=38 cycles);group B,poor-quality or mixed-quality SeET(PQ/MQ-SeET,n=31 cycles);group C,good-quality DBT(GQ-DBT,n=121 cycles);and group D,poor-quality or mixed-quality DBT(PQ/MQ-DBT,n=71 cycles).The main outcome,clinical pregnancy rate,was compared,and the generalized estimating equation(GEE)model was used to correct potential confounders that might impact pregnancy outcomes.Results GQ-DBT achieved a significantly higher clinical pregnancy rate(aOR 2.588,95%CI 1.267–5.284,P=0.009)and live birth rate(aOR 3.082,95%CI 1.482–6.412,P=0.003)than PQ/MQ-DBT.Similarly,the clinical pregnancy rate was significantly higher in GQ-SeET than in PQ/MQ-SeET(aOR 4.047,95%CI 1.218–13.450,P=0.023).The pregnancy outcomes of GQ-SeET were not significantly different from those of GQ-DBT,and the same results were found between PQ/MQ-SeET and PQ/MQ-DBT.Conclusion SeET relative to DBT did not seem to improve pregnancy outcomes for RIF patients if the embryo quality was comparable between the two groups.Better clinical pregnancy outcomes could be obtained by transferring good-quality embryos,no matter whether in SeET or DBT.Embryo quality plays a more important role in pregnancy outcomes for RIF patients. 展开更多
关键词 recurrent implantation failure sequential embryo transfer frozen-thawed embryo transfer embryo transfer strategies
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Reducing the Trigger Dose of Human Chorionic Gonadotrophin Does Not Affect Final Oocyte Maturation and Subsequently Pregnancy Outcome of Frozen-thawed Embryo Transfer
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作者 Yun WANG Yong-lun FU +4 位作者 Shao-feng CAO Qiu-ju CHEN Song-guo XUE Qi-feng LYU Yan-ping KUANG 《Journal of Reproduction and Contraception》 CAS 2013年第3期151-158,共8页
To compare the efficacy of human chorionic gonadotrophin (hCG) at reduced doses of 2 000 IU and 3 000 IU for moderate or high responders with the dose of 5 000 IU in term of inducing final oocyte maturation for IV... To compare the efficacy of human chorionic gonadotrophin (hCG) at reduced doses of 2 000 IU and 3 000 IU for moderate or high responders with the dose of 5 000 IU in term of inducing final oocyte maturation for IVF/ICSI and the subsequent pregnancy outcome in frozen-thawed embryo transfer (FET). Methods In the retrospective cohort study, 2 166patients undergoing IVF/ICSI with moderate or high response were recruited and classified into three groups according to the trigger dose of hCG: 2 000 IU (group A, n=722), 3 000 IU (group B, n=722) and 5 000 IU (group C, n= 722). The main outcome was the proportion of mature oocytes retrieved, fertilization rates, clinical pregnancy rates, cumulative pregnancy rates and incidence of ovarian hyperstimulation syndrome (OHSS). Results No evidence of statistically difference was found in the proportion of mature oocytes retrieved (89.92%, 91.40%, 90.20%, respectively) and fertilization rate (79.8%, 80.07%, 80.51%, respectively) among groups A, B and C. Serum E2 level on the day of hCG injection, the number of mature oocytes retrieved and good-quality embryos in group A were significantly higher than those in group B and group C. Clinical pregnancy rates per transfer cycle (45.95%, 43.97% and 44.25%), ongoing pregnancy rates (43.17%, 40.91% and 42,53%), implantation rates (30, 74%, 2Z 78% and 29.86%) and cumulative pregnancy rates per patient (58.31%, 53.6% and 54.85%)A reduced hCG dose of 2 000 IUfor moderate or high responders leads 展开更多
关键词 human chorionic gonadotropin (hCG) controlled ovarian hyperstimulation (COH) ovarian hyperstimulation syndrome (OHSS) frozen-thawed embryo transfer (FET) cumulative pregnancy rate (CPR)
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Serum β-hCG level on day 7 of frozen-thawed embryo transfer: association with the clinical pregnancy outcomes in artificial cycles
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作者 Na Sun Shu-Yi Dong +1 位作者 Ping-Ping Sun Hua-Gang Ma 《Clinical Research Communications》 2022年第3期29-33,共5页
Objective:The relationship between serum beta human chorionic gonadotropin(β-hCG)levels of patients(7 days after the transplantation of frozen-thawed embryos)and the pregnancy outcomes was investigated.Methods:This s... Objective:The relationship between serum beta human chorionic gonadotropin(β-hCG)levels of patients(7 days after the transplantation of frozen-thawed embryos)and the pregnancy outcomes was investigated.Methods:This study was designed as a retrospective clinical trial of 366 women who underwent frozen-thawed embryo transfers(FETs)in artificial cycles.Patients were divided into three groups:clinical pregnancy group,biochemical pregnancy group,and non-pregnant group according to their pregnancy outcomes.Serumβ-hCG levels were tested on day 4,7,9,11 and 14 after FET.Results:In the clinical pregnancy group,the serumβ-hCG levels after 7-day post-transplantation were significantly elevated(16.20 IU/L vs.3.07 vs.0.1 IU/L;P<0.05)compared with the other two groups.Furthermore,it was found that Area Under Curve(AUC=0.96)was significant with cut-off value higher than 4.26 IU/L(sensitivity=92.3%,specificity=90.2%)to predict the clinical pregnancy outcomes in the receiver operating characteristic(ROC)analysis ofβ-hCG concentrations on day 7 of post-transplantation.Conclusion:Our results suggested that the elevated serumβ-hCG levels on day 7 of post-transplantation could predict the positive clinical pregnancy outcomes in artificial FET cycles. 展开更多
关键词 frozen-thawed embryo transfer pregnancy outcomes artificial cycle human chorionic gonadotrophin INFERTILITY
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Real-life practice of Kelleni’s protocol in treatment and post exposure prophylaxis of SARS-CoV-2 HV.1 and JN.1 subvariants 被引量:1
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作者 Mina Thabet Kelleni 《World Journal of Virology》 2025年第3期1-5,共5页
This article discusses the evolving real-world practice using nitazoxanide,nonsteroidal anti-inflammatory drugs(NSAIDs)and/or azithromycin(Kelleni’s protocol)to manage the evolving manifestations of severe acute resp... This article discusses the evolving real-world practice using nitazoxanide,nonsteroidal anti-inflammatory drugs(NSAIDs)and/or azithromycin(Kelleni’s protocol)to manage the evolving manifestations of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)Omicron EG.5.1,its descendant HV.1 as well as BA.2.86 and its descendant JN.1 subvariants in Egypt in 2024.These subvariants are well-known for their highly evolved immune-evasive properties and the manifestations include some peculiar manifestations as persistent cough besides high fever in young children as well as high fever,persistent severe cough,change of voice,loss of taste and smell,epigastric pain,nausea,vomiting,diarrhea,generalized malaise and marked bone aches in adults including the high-risk groups.It’s suggested that the ongoing SARS-CoV-2 evolution is continuing to mostly affect the high-risk groups of patients,to some of whom we’ve also successfully prescribed nitazoxanide and/or NSAIDs for post-exposure prophylaxis of all household contacts.We also continue to recommend starting the immune-modulatory antiviral Kelleni’s protocol as soon as possible in the course of infection and adjusting it in a personalized manner to be more aggressive from the beginning for the high risk patients,at least until the currently encountered surge of infections subsides. 展开更多
关键词 SARS-CoV-2 HV.1 JN.1 post exposure prophylaxis Kelleni’s protocol NITAZOXANIDE Non-steroidal anti-inflammatory drugs
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Mechanism of post cardiac arrest syndrome based on animal models of cardiac arrest
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作者 Halidan ABUDU WANG Yiping +10 位作者 HE Kang LIU Ziquan GUO Liqiong DONG Jinrui Ailijiang KADEER XU Guowu LIU Yanqing MENG Xiangyan CAI Jinxia LI Yongmao FAN Haojun 《中南大学学报(医学版)》 北大核心 2025年第5期731-746,共16页
Cardiac arrest(CA)is a critical condition in the field of cardiovascular medicine.Despite successful resuscitation,patients continue to have a high mortality rate,largely due to post CA syndrome(PCAS).However,the inju... Cardiac arrest(CA)is a critical condition in the field of cardiovascular medicine.Despite successful resuscitation,patients continue to have a high mortality rate,largely due to post CA syndrome(PCAS).However,the injury and pathophysiological mechanisms underlying PCAS remain unclear.Experimental animal models are valuable tools for exploring the etiology,pathogenesis,and potential interventions for CA and PCAS.Current CA animal models include electrical induction of ventricular fibrillation(VF),myocardial infarction,high potassium,asphyxia,and hemorrhagic shock.Although these models do not fully replicate the complexity of clinical CA,the mechanistic insights they provide remain highly relevant,including post-CA brain injury(PCABI),post-CA myocardial dysfunction(PAMD),systemic ischaemia/reperfusion injury(IRI),and the persistent precipitating pathology.Summarizing the methods of establishing CA models,the challenges encountered in the modeling process,and the mechanisms of PCAS can provide a foundation for developing standardized CA modeling protocols. 展开更多
关键词 cardiac arrest animal model post cardiac arrest syndrome PATHOPHYSIOLOGY modeling method
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The desert post office
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作者 胡金莹 《疯狂英语(新读写)》 2025年第12期52-53,78,共3页
Deep in the Tengger Desert of Inner Mongolia autonomous region,surrounded by sand as far as the eye can see,lies the world's loneliest post office.Measuring only 15 square meters,the wooden post office doesn't... Deep in the Tengger Desert of Inner Mongolia autonomous region,surrounded by sand as far as the eye can see,lies the world's loneliest post office.Measuring only 15 square meters,the wooden post office doesn't get too many visitors anyway.But after being abandoned for over 35 years,it actually doesn't look half bad. 展开更多
关键词 ABANDONMENT Inner Mongolia Autonomous Region loneliest post office post office wooden post office DESERT sand Tengger Desert
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Synthesis of New Functionalized Polymers Through the Post-Modification of Polyvinyl Chloride
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作者 Yuchen Li Ruochen Cao +4 位作者 Yuxiang Qin Haoran Zhang Xiaoyan Tang Meng Wang Ding Ma 《Carbon and Hydrogen》 2025年第1期52-57,共6页
Polyvinyl chloride(PVC)is one of the most widely used plastic materials worldwide,particularly in long-life applications such as construction materials.However,recycling options for PVC waste remain limited,as convent... Polyvinyl chloride(PVC)is one of the most widely used plastic materials worldwide,particularly in long-life applications such as construction materials.However,recycling options for PVC waste remain limited,as conventional methods often degrade material quality or generate environmentally hazardous byproducts.In this study,we demonstrate an efficient process to convert PVC into new polymers with variable aromatic groups,using triethylsilane as the reductant in different solvents.This approach enables the production of polymers analogous to functionalized polyethylene(PE),which are typically challenging to obtain through conventional copolymerization or direct post-modification of C-H bonds in PE.The resulting polymers exhibit tunable thermal and mechanical properties depending on the introduced aromatic groups,which not only enhance the sustainable valorization of PVC waste,but also provide an opportunity for the synthesis of new functionalized polymers. 展开更多
关键词 functionalized polymer polyvinyl chloride post‐modification upcycling
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Tailoring microstructure,tensile properties,and creep resistance of additively manufactured Inconel 718 superalloy by post heat treatment
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作者 Sajad GHAEMIFAR Milad ROOSTAEI +2 位作者 Mohammad REZA ZAMANI Stefan WURSTER Hamed MIRZADEH 《Transactions of Nonferrous Metals Society of China》 2025年第6期1890-1906,共17页
The effects of post heat treatment on the microstructure,aging kinetics,and room/elevated temperature mechanical properties of additively manufactured Inconel 718 superalloy were investigated.Scanning electron microsc... The effects of post heat treatment on the microstructure,aging kinetics,and room/elevated temperature mechanical properties of additively manufactured Inconel 718 superalloy were investigated.Scanning electron microscopy(SEM),electron backscattered diffraction(EBSD),and X-ray diffraction(XRD),as well as hardness,tensile,and creep testing were used for characterization.At temperatures higher than 1100°C,homogenization treatment resulted in the appearance of equiaxed grains by recrystallization and diminishing the dislocation density.The precipitation activation energy for the homogenized and aged condition was obtained as 203.2 kJ/mol,which was higher than the value of~160 kJ/mol for the as-built IN718 superalloy.Therefore,direct aging resulted in a faster aging response,which led to a significant improvement in tensile properties,as rationalized by the strengthening mechanisms.Direct aging treatment resulted in a higher elevated-temperature ultimate tensile strength(UTS)as well as the optimum creep life and the lowest minimum creep rate in comparison with other heat treatment routes,which were attributed to the presence of fine and uniformly dispersed strengthening precipitates in conjunction with the high dislocation density. 展开更多
关键词 Inconel 718 superalloy additive manufacturing post heat treatment mechanical properties creep resistance
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Seismic design of variable cross-section damped steel support frame for post equipment
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作者 Yang Zhenyu Ma Yuhong +2 位作者 Zhao Guifeng Feng Zhiwei Fu Mingyang 《Earthquake Engineering and Engineering Vibration》 2025年第1期155-167,共13页
High-voltage electrical post equipment is generally installed on steel supports,which amplifies the seismic inputs and degrades the seismic performance of equipment.This study proposed a variable cross-section damped ... High-voltage electrical post equipment is generally installed on steel supports,which amplifies the seismic inputs and degrades the seismic performance of equipment.This study proposed a variable cross-section damped steel support frame(VCDFS)with viscous dampers to reduce seismic responses of both tall and low-rise electrical equipment.The VCDFS contains a trapezoidal damper layer to generate rocking motions,enabling the diagonal viscous dampers to dissipate seismic inputs.A theoretical model of post equipment with VCDFS is established,and an optimal design procedure is proposed.The analysis shows that the remaining static stiffness ratio λ_(k) is the key parameter that determines the effectiveness of the VCDFS.The VCDFS reduces the average displacement and stress response of a post insulator by 39.4%and 44.6%,respectively,together with a significant decrease in the dynamic amplification factor.Therefore,it is recommended to use the VCDFS instead of the conventional latticed-steel frame in earthquake zones. 展开更多
关键词 electrical post equipment steel support frame passive control seismic performance upgrading
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Effect of Post Weld Heat Treatment on Residual Stress and Mechanical Properties of 106 mm Thick TC4 Titanium Alloy Electron Beam Welded Joints
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作者 Yunlu Jiang Lihui Wu +5 位作者 Dingrui Ni Hongbo Zhao Xu Han Peng Xue Bolv Xiao Zongyi Ma 《Acta Metallurgica Sinica(English Letters)》 2025年第7期1083-1094,共12页
This study analyzed through-thickness distribution of residual stress in a 106 mm ultra-thick TC4 titanium alloy electron beam welded(EBW)joint after post weld heat treatment(PWHT)using X-ray diffraction(XRD)and deep-... This study analyzed through-thickness distribution of residual stress in a 106 mm ultra-thick TC4 titanium alloy electron beam welded(EBW)joint after post weld heat treatment(PWHT)using X-ray diffraction(XRD)and deep-hole drilling(DHD)methods,and investigated the microstructure and mechanical properties.During the PWHT at 600℃,a phase transformation(β→α)occurred in the EBW joint and affected the residual stress distribution and mechanical properties.The surface residual stress was mainly compressive stress,while the internal residual stress was mainly tensile stress in the welded joint.For the as-welded joint,the absolute value of surface residual stress was higher than the absolute value of internal residual stress.After PWHT,the residual stress in the treated joint was substantially reduced compared to the as-welded joint,particularly the surface stress,which relieved from−425 to−90 MPa.However,the residual stress relief effect had minimal positive impact on the internal region at 600℃.PWHT resulted in a shift of the joint fracture location from the fusion zone(FZ)to the base metal(BM),and therefore exerted no noticeable effect on the joint strength,but increased the joint elongation significantly.This study provides valuable insights into the regulation of residual stress distribution of ultra-thick titanium alloy plates. 展开更多
关键词 Titanium alloy Electron beam welding Residual stress post weld heat treatment Mechanical property
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Strength Optimization of Diffusion-Bonded Ti_(2)AlNb Alloy by Post-Heat Treatment
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作者 Haijian Liu Tianle Li +3 位作者 Xifeng Li Huiping Wu Zhiqiang Wang Jun Chen 《Acta Metallurgica Sinica(English Letters)》 2025年第4期614-626,共13页
Diffusion-bonded Ti_(2)AlNb-based alloys commonly present a low strength compared with the deformed or aged ones. In this study, the post heat treatment including solution and aging treatments is proposed to optimize ... Diffusion-bonded Ti_(2)AlNb-based alloys commonly present a low strength compared with the deformed or aged ones. In this study, the post heat treatment including solution and aging treatments is proposed to optimize the microstructure, contributing to strength improvement and appropriate ductility sacrifice. An available method by the introduction of fine size (both 20-100 nm) and a high fraction (59.7% and 13.7%) of O and α_(2) phases using both solution at 1000℃ for 1 h and aging at 750℃ for 5 h can result in excellent tensile strength (992 MPa and 858 MPa) at room temperature and 650℃, respectively, which increases 5.3% and 44.5% than that of as-received sample. The aging treatment can contribute to lamellar O and α2 grains precipitated from the B_(2) parent, which results in limited dislocation slip systems and slip spaces to resist plastic deformation. Moreover, the crack propagation and fracture surfaces are also comparatively analyzed to reveal the fracture behaviors in the samples with high and low strength. This study can provide a new method for the mechanical property optimization of the welded Ti_(2)AlNb alloys. 展开更多
关键词 Ti_(2)AlNb alloy Diffusion bonding post heat treatment Phase transformation Mechanical properties
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Post-cardiac arrest imaging:Unraveling etiology and predicting neurological outcome
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作者 George Latsios Elias Sanidas +6 位作者 Maria Velliou Marina Kalogridaki Pavlos Bounas Andreas Synetos Constantina Aggeli Konstantinos Toutouzas Costas Tsioufis 《World Journal of Radiology》 2025年第9期73-82,共10页
Cardiac arrest is associated with high rates of mortality and significant long-term neurological disability in survivors.Timely and accurate assessment following successful resuscitation is critical for optimizing out... Cardiac arrest is associated with high rates of mortality and significant long-term neurological disability in survivors.Timely and accurate assessment following successful resuscitation is critical for optimizing outcomes.Imaging plays a central role in this evaluation process,providing crucial insights into the etiology of arrest,the extent of cerebral and cardiac injury,and guiding both acute management and long-term prognostication.A structured,multimodal imaging approach utilizing tools such as computed tomography,magnetic resonance imaging,echocardiography,and angiography is increasingly recognized as es-sential in the post-cardiac arrest setting.This review aims to consolidate current evidence related to the use of various imaging modalities across neurological,cardiac and systemic contexts.Particular emphasis is placed on the prognostic value and optimal timing of neuroimaging,the detection of potentially reversible causes of arrest,such as coronary occlusion or pulmonary embolism,and the emerging role of whole-body imaging in evaluating patients with non-traumatic out-of-hospital cardiac arrest. 展开更多
关键词 post cardiac arrest setting Return of spontaneous circulation IMAGING Computed tomography Magnetic resonance imaging Coronary angiography ECHOCARDIOGRAPHY
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Changes in the Post-War World Order and China’s UN Diplomacy
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作者 Wang Cungang 《Contemporary World》 2025年第6期21-27,共7页
The year 2025 marks the 80th anniversary of the founding of the United Nations(UN).As the most universal,representative,and authoritative intergovernmental international organization in the world,the UN serves as the ... The year 2025 marks the 80th anniversary of the founding of the United Nations(UN).As the most universal,representative,and authoritative intergovernmental international organization in the world,the UN serves as the core platform for upholding multilateralism and a crucial cornerstone of the international order.In recent years,the UN’s ability to address global challenges is tested. 展开更多
关键词 upholding multilateralism MULTILATERALISM global challenges post war world order international order th anniversary United Nations united nations un
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Psychoactive Substances:Transforming the Paradigm for Treating Mental Health Disorders in the Post‑Pandemic Era
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作者 Haojiang Zhai Yibo Wang Xiaohui Wang 《Neuroscience Bulletin》 2025年第3期536-538,共3页
Mental health disorders have emerged as a critical global health challenge,profoundly impacting individuals,communities,and societies worldwide.The prevalence of mental health problems has been steadily increasing,wit... Mental health disorders have emerged as a critical global health challenge,profoundly impacting individuals,communities,and societies worldwide.The prevalence of mental health problems has been steadily increasing,with~1 in 8 people,equivalent to 970 million individuals suffering from a mental disorder in 2019(https://vizhub.healthdata.org/gbd-results).Anxiety and depressive disorders are predominant,contributing significantly to the burden of mental health issues,according to the World Health Organization.The COVID-19 pandemic has further exacerbated this situation.It led to a notable upsurge in anxiety and major depressive disorders in 2020.Estimates indicate a 26%rise in anxiety and a 28%increase in depression within that year(https://www.who.int/publications/i/item/WHO-2019-nCoVSci_Brief-Mental_health-2022.1)[1]. 展开更多
关键词 psychoactive substances depressive disorders post pandemic era mental health disorders mental disorder global health challenge mental health problems ANXIETY
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Legacies of viral pandemics:the philosophy of post-infection rehabilitation
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作者 Abigail O.Akande 《History and Philosophy of Medicine》 2025年第4期42-44,共3页
The diagnosis and treatment processes for long COVID have been relatively slow to develop for several reasons,such as a lack of consensus about its definition among medical professionals and researchers,and restricted... The diagnosis and treatment processes for long COVID have been relatively slow to develop for several reasons,such as a lack of consensus about its definition among medical professionals and researchers,and restricted access to knowledge from the relevant pandemics of the past.Legacies of viral pandemics unfortunately do not include sufficient research on how the acute symptoms of infection evolved into chronic health conditions.More so,the idea of surviving a viral pandemic with long-lasting symptoms is not new,yet it is curiously disjointed as a medical concept throughout documented histories on the subject.Individuals with long-term conditions that are rooted in acute viral infections,such as COVID-19,require a coordinated system of care that includes comprehensive rehabilitation.This commentary will discuss the philosophical underpinnings of the historical scarcity of documented incidences of individuals with chronic virus symptoms and the need for a shift in post-viral infection treatment approaches. 展开更多
关键词 long COVID viral pandemics medical philosophy diagnosis treatment processes historical incidences long covid post infection rehabilitation chronic health conditions
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