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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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Current Medical Science 2024年第1期44卷 212-222页

作者： Qiao-hang ZHAO Yu-wei SONG Jian chen xiang ZHOU Ji-lai XIE Qiu-ping YAO Qi-yin DONG chun FENG Li-ming ZHOU Wei-ping FU Min JIN The Second Affiliated Hospital of Zhejiang University School of Medicine Hangzhou 310052China Jiaxing Maternity and Child Health Care Hospital Jiaxing 314051China Huzhou Maternity and Child Care Hospital Huzhou 313002China Ningbo Women and Children's Hospital Ningbo 315000China

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.

关键词： recurrent implantation failure sequential embryo transfer frozen-thawed embryo transfer embryo transfer strategies

Modeling of LF refining process:a review

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Journal of Iron and Steel Research(International) 2024年第2期31卷 289-317页

作者： Zi-cheng Xin Jiang-shan Zhang Kai-xiang Peng Jun-guo Zhang chun-hui Zhang Qing Liu State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing100083China School of Automation and Electrical Engineering University of Science and Technology BeijingBeijing100083China Tangshan Branch Hebei Iron and Steel Co.Ltd.Tangshan063000HebeiChina Xinjiang Bayi Iron and Steel Co. Ltd.Baosteel GroupWulumuqi830022XinjiangChina

With the increasing demand for energy conservation and emission reduction,more attentions have been paid to the intelligentization,greenization and low carbonization during the transformation and upgrading of steelmaking plants.Ladle furnace(LF)refining is one of the key procedures in steelmaking process and has been widely used in steelmaking plants for its high equipment matching degree,low equipment investment and outstanding refining performance.According to the main tasks of LF refining process,the modeling methods of temperature prediction model,slag-making model,alloying model,argon blowing model and model of inclusions behavior were systematically reviewed,and the advantages and disadvantages of each modeling method were summarized.In addition,the technical framework for the future has also been proposed based on existing works,including classification of raw materials,graphic representation of knowledge,introduction,upgradation and management of device/equipment,customization of steelmaking,modeling of refining process,synergy of models,intelligentization of decision-making,automation of control,and digitization of processes and operations,aiming to provide a reference for the modeling and intelligent development of LF refining process.

关键词： LF refining Temperature prediction Slag-making Alloying Argon blowing Inclusion behavior Modeling method

A novel algorithm for evaluating cement azimuthal density based on perturbation theory in horizontal well

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Petroleum Science 2024年第1期21卷 244-251页

作者： Ji-Lin Fan Feng Zhang Qian chen Hao-chen Song Lu-Yu Zhong Yue-xiang Dai National Key Laboratory of Deep Oil and Gas School of GeosciencesChina University of Petroleum(East China)Qingdao 266580ShandongChina China National Logging Corporation Xi'an 710076ShaanxiChina Sinopec Matrix Corporation Qingdao 266001ShandongChina

Cement density monitoring plays a vital role in evaluating the quality of cementing projects,which is of great significance to the development of oil and gas.However,the presence of inhomogeneous cement distribution and casing eccentricity in horizontal wells often complicates the accurate evaluation of cement azimuthal density.In this regard,this paper proposes an algorithm to calculate the cement azimuthal density in horizontal wells using a multi-detector gamma-ray detection system.The spatial dynamic response functions are simulated to obtain the influence of cement density on gamma-ray counts by the perturbation theory,and the contribution of cement density in six sectors to the gamma-ray recorded by different detectors is obtained by integrating the spatial dynamic response functions.Combined with the relationship between gamma-ray counts and cement density,a multi-parameter calculation equation system is established,and the regularized Newton iteration method is employed to invert casing eccentricity and cement azimuthal density.This approach ensures the stability of the inversion process while simultaneously achieving an accuracy of 0.05 g/cm^(3) for the cement azimuthal density.This accuracy level is ten times higher compared to density accuracy calculated using calibration equations.Overall,this algorithm enhances the accuracy of cement azimuthal density evaluation,provides valuable technical support for the monitoring of cement azimuthal density in the oil and gas industry.

关键词： Cement azimuthal density Perturbation theory Casing eccentricity Spatial dynamic response function Regularized Newton iteration

维普期刊数据库

Molecular investigation into the transformation of recalcitrant dissolved organic sulfur in refinery sour water during stripping process

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Petroleum Science 2024年第3期21卷 2112-2119页

作者： Yu-Guo Li chen He chun-Mao chen Fan Liu Quan Shi State Key Laboratory of Heavy Oil Processing China University of Petroleum State Key Laboratory of Coal Mining and Clean Utilization PetroChina Ningxia Petrochemical Company

Refinery sour water primarily originates from the tops of towers in various units and coker condensate,and cannot be discharged directly to a wastewater treatment plant due to high levels of chemical oxygen demand(COD) and organic sulfur contents. Even after the recovery of H2S from the sour water by the stripping process, the effluent still contains a high concentration of dissolved organic sulfur(DOS), which can have a huge bad influence. While chemical composition of dissolved organic matter(DOM) in refinery wastewater has been extensively studied, the investigation of recalcitrant DOS from sour waters remains unclear. In the present study, chemical composition of sour water DOMs(especially DOS) was investigated using fluorescence spectroscopy(excitation-emission matrix, EEM) and mass spectrometry,including gas chromatography-mass spectrometry(GC-MS) and high-resolution Orbitrap MS. The GC-MS and EEM results showed that volatile and low-aromaticity compounds were effectively removed during the stripping process, while compounds with high hydrophilicity and humification degree were found to be more recalcitrant. The Orbitrap MS results showed that weak-polar oxygenated sulfur compounds were easier to be removed than oxygenated compounds. However, the effluent still contained significant amounts of sulfur-containing compounds with multiple sulfur atoms, particularly in the form of highly unsaturated and aromatic compounds. The Orbitrap MS/MS results of CHOS-containing compounds from the effluent indicate that the sulfur atoms may exist as sulfonates, disulfide bonds, thioethers. Understanding the composition and structure of sour water DOS is crucial for the development of effective treatment processes that can target polysulfide compounds and minimize their impact on the environment.

关键词： Molecular transformation Dissolved organic sulfur Stripping process Refinery sour water Orbitrap MS

Robot-Oriented 6G Satellite-UAV Networks: Requirements, Paradigm Shifts, and Case Studies

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China Communications 2024年第2期21卷 74-84页

作者： Peng Wei Wei Feng Yunfei chen Ning Ge Wei xiang Department of Electronic Engineering Tsinghua UniversityBeijing 100084China Department of Engineering University of DurhamDH13LEDurhamUK School of Computing Engineering and Mathematical SciencesLa Trobe UniversityMelbourneVIC 3086Australia

Networked robots can perceive their surroundings, interact with each other or humans,and make decisions to accomplish specified tasks in remote/hazardous/complex environments. Satelliteunmanned aerial vehicle(UAV) networks can support such robots by providing on-demand communication services. However, under traditional open-loop communication paradigm, the network resources are usually divided into user-wise mostly-independent links,via ignoring the task-level dependency of robot collaboration. Thus, it is imperative to develop a new communication paradigm, taking into account the highlevel content and values behind, to facilitate multirobot operation. Inspired by Wiener’s Cybernetics theory, this article explores a closed-loop communication paradigm for the robot-oriented satellite-UAV network. This paradigm turns to handle group-wise structured links, so as to allocate resources in a taskoriented manner. It could also exploit the mobility of robots to liberate the network from full coverage,enabling new orchestration between network serving and positive mobility control of robots. Moreover,the integration of sensing, communications, computing and control would enlarge the benefit of this new paradigm. We present a case study for joint mobile edge computing(MEC) offloading and mobility control of robots, and finally outline potential challenges and open issues.

关键词： closed-loop communication mobility control satellite-UAV network structured resource allocation

维普期刊数据库

Intestinal malrotation complicated with gastric cancer: A case report

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World Journal of Clinical Cases 2024年第1期12卷 210-216页

作者： xiang-Hao Jia Shuai Kong Xin-Xin Gao Bi-Cong Cong chun-Ning Zheng School of Clinical Medicine Weifang Medical UniversityWeifang 261053Shandong ProvinceChina Department of Gastrointestinal Surgery Provincial Hospital Affiliated to Shandong First Medical UniversityJinan 250000Shandong ProvinceChina

BACKGROUND Intestinal malrotation is a congenital defect of embryonic development caused by various teratogenic factors.In this condition,the intestinal tube,along with the superior mesenteric artery serving as the axis for the counterclockwise movement,is incomplete or abnormally rotated due to incomplete attachment of the mesentery and abnormal intestinal tube position.Such a case is usually asymp-tomatic and thus difficult to detect.Therefore,similar variant malformations are only found during an operation required for other abdominal diseases.CASE SUMMARY An elderly male patient was admitted to the hospital due to gastric cancer.An abdominal computed tomography(CT)scan with contrast revealed that the ascending and descending colon were parallel on the right side of the abdominal cavity,while the sigmoid colon extended into the right iliac fossa,allowing the diagnosis of congenital midgut malrotation.Following thorough preoperative preparation,the patient underwent laparoscopic radical gastrectomy to treat his gastric cancer.Intraoperatively,an exploration of the abdominal cavity uncovered the absence of the transverse colon.The distal colon at the hepatic flexure,along with the ascending colon,extended into the right iliac fossa,where it continued as the sigmoid colon.As planned,the laparoscopic radical gastrectomy was perform-ed,and the patient was discharged from the hospital 7 d after the surgery.CONCLUSION Asymptomatic intestinal malrotation is best detected by CT,requiring no treatment but possibly interfering with the treatment of other diseases.

关键词： Intestinal malrotation Congenital malformation Gastric cancer Abdominal

Assembling S-scheme heterojunction between basic bismuth nitrate and bismuth tungstate with promoting charges’separation for accelerated photocatalytic sulfamethazine degradation

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Journal of Materials Science & Technology 2024年第4期171卷 185-197页

作者： Wenhan chen Meng Dai Li xiang Shan Zhao Shuguang Wang Zuoli He Shandong Key Laboratory of Water Pollution Control and Resource Reuse Shandong Key Laboratory of Environmental Processes and HealthSchool of Environmental Science and EngineeringShandong UniversityQingdao 266237China CEDAR Knight Cancer InstituteSchool of MedicineOregon Health and Science UniversityPortlandOR 97201United States Weihai Research Institute of Industrial Technology of Shandong University Shandong UniversityWeihai 264209China

The S-scheme heterojunction has garnered increasing attention due to its remarkable oxidation capacity and efficient separation of photogenerated carriers.In this study,a one-pot glycerol-assisted hydrothermal process was utilized to successfully synthesize S-scheme heterojunction photocatalysts comprising basic bismuth nitrate(BBN)and bismuth tungstate(BWO).Interestingly,the BBN/BWO heterogeneous photo-catalysts exhibited the highest photocatalytic properties.The optimized product achieved the degradation of sulfamethazine(SMZ)within 1 h,with a kinetic constant(k)value of 0.05818 min^(−1).The degradation process was influenced significantly by·O^(2)−and h^(+)species.To determine the degradation pathway of SMZ in the presence of BBN/BWO-0.6,liquid chromatography-mass spectrometry(LC-MS)analysis was performed,which revealed a decrease in the toxicity of intermediates and products.The enhanced pho-tocatalytic activity can be attributed to the internal electric field(IEF)of the S-scheme heterojunction between BBN and BWO,effectively promoting the separation of photogenerated carriers.This research presents a viable approach for developing S-scheme heterojunctions in SMZ photodegradation and other environmental applications.

关键词： Photocatalysis S-scheme Heterojunction Bi_(2)WO_(6) Sulfamethazine

Atroposelective Synthesis of 2-Arylindoles via Chiral Phosphoric Acid-Catalyzed Direct Amination of Indoles

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Chinese Journal of Chemistry 2024年第7期42卷 731-735页

作者： Wen Bao Ye-Hui chen Yu-Wei Liu Shao-Hua xiang Bin Tan School of Pharmacy&StateKey Laboratory of Applied Organic Chemistry Lanzhou UniversityLanzhouGansu 730000China Shenzhen Grubbs Institute Department of ChemistrySouthern University of Science and TechnologyShenzhenGuangdong 518055China

Indole-based atropisomers are a very important class of axially chiral compounds.However,the atroposelective synthesis of axially chiral 2-arylindole remains largely unexplored.In this study,we report the successful synthesis of atropisomeric 2-arylindoles using direct amination of indoles with p-quinonediimines in the presence of chiral phosphoric acid as a catalyst.Quinonediimine acts as an aminating reagent through formal polarity inversion of imine.The malonate group on the 2-aryl of 2-indoles was found to be essen-tial for high enantioselectivity of the products.This could be due to the additional interaction between the ester group and the cata-lyst,as well as the intramolecular hydrogen bonding.Our findings provide a new strategy for the asymmetric construction of 2-arylindole atropisomers.

关键词： Chiral phosphoric acid Quinonediimines Direct amination Nucleophilic addition Asymmetric catalysis Enantioselectivity Axially chiral 2-arylindole Atroposelective synthesis

Correlation and Pathway Analysis of the Carbon,Nitrogen,and Phosphorus in Soil-Microorganism-Plant with Main Quality Components of Tea(Camellia sinensis)

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Phyton-International Journal of Experimental Botany 2024年第3期93卷 487-502页

作者： chun Mao Ji He Xuefeng Wen Yangzhou xiang Jihong Feng Yingge Shu College of Agriculture Guizhou UniversityGuiyangChina School of Geography and Resources Guizhou Education UniversityGuiyangChina

The contents of carbon(C),nitrogen(N),and phosphorus(P)in soil-microorganisms-plant signiﬁcantly affect tea quality by altering the main quality components of tea,such as tea polyphenols,amino acids,and caffeine.However,few studies have quantiﬁed the effects of these factors on the main quality components of tea.The study aimed to explore the interactions of C,N,and P in soil-microorganisms-plants and the effects of these factors on the main quality components of tea by using the path analysis method.The results indicated that(1)The contents of C,N,and P in soil,microorganisms,and tea plants were highly correlated and collinear,and showed signiﬁcant correlations with the main quality components of tea.(2)Optimal regression equations were established to esti-mate tea polyphenol,amino acid,catechin,caffeine,and water extract content based on C,N,and P contents in soil,microorganisms,and tea plants(R^(2)=0.923,0.726,0.954,0.848,and 0.883,respectively).(3)Pathway analysis showed that microbial biomass phosphorus(MBP),root phosphorus,branch nitrogen,and microbial biomass carbon(MBC)were the largest direct impact factors on tea polyphenol,catechin,water extracts,amino acid,and caffeine content,respectively.Leaf carbon,root phosphorus,and leaf nitrogen were the largest indirect impact factors on tea polyphenol,catechin,and water extract content,respectively.Leaf carbon indirectly affected tea polyphenol content mainly by altering MBP content.Root phosphorus indirectly affected catechin content mainly by altering soil organic carbon content.Leaf nitrogen indirectly affected water extract content mainly by altering branch nitrogen content.The research results provide the scientiﬁc basis for reasonable fertilization in tea gardens and tea quality improvement.

关键词： Soil-microorganisms-plant system carbon nitrogen phosphorus tea quality path analysis