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Factors affecting failed trial of labor and countermeasures:A retrospective analysis

World Journal of Clinical Cases 2020年第16期8卷 3483-3492页

作者： jin-guang wang jing-Li Sun Jian Shen Department of Obstetrics and Gynecology General Hospital of Northern Theater Command(Heping Campus)Shenyang 110000Liaoning ProvinceChina

BACKGROUND Vaginal delivery is the ideal mode of delivery for the termination of a ***,the cesarean section rate in China is much higher than the published by the World Health Organization in the Lancet in *** To retrospectively analyze the factors related to failed trial of labor and the clinical indications for cesarean section conversion,explore how to promote the trial of labor success rate,and determine the feasibility of reducing the rate of conversion to cesarean *** A retrospective analysis was performed on 9240 maternal women who met vaginal delivery conditions and required a trial of labor from January 2016 to December 2018 at our *** them,8164 pregnant women who had a successful trial of labor were used as a control group,and 1076 pregnant women who had a failed trial of labor and converted to an emergency cesarean section were used as an observation *** patients’clinical data during hospitalization were collected for comparative analysis,the related factors of the failed trial of labor were discussed,and reasonable prevention and resolution strategies were proposed to increase the success rate of trial of *** The analysis revealed that advanced age(≥35 years old),macrosomia(≥4000 g),delayed pregnancy(≥41 wk),use of uterine contraction drugs,primipara,and fever during labor were associated with conversion to an emergency cesarean section in the failed trial of *** regression analysis showed that age,gestational age,primipara,use of uterine contraction drugs,fever duringbirth,and newborn weight led to a higher probability of conversion to an emergency cesarean section in the failed trial of *** analysis indicated that the following clinical indications were associated with the conversion to cesarean section in the failed trial of labor:Fetal distress(44.3%),social factors(12.8%),malpresentation(face presentation,persistent occipitoposterior position,and persistent occipitotransv

关键词： Trial of labor Vaginal delivery Cesarean section Dystocia Retrospective analysis

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Precipitation Behavior of V-N Microalloyed Steels during Normalizing

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Journal of Iron and Steel Research International 2015年第11期22卷 1037-1042页

作者： Tao PAN Xi-yang CHAI jin-guang wang Hang SU Cai-fu YANG Division of Structural Steels Central Iron and Steel Research Institute Division of Equipment Construction China Sinopec Engineering Incorporation

The precipitation behavior of V-N microalloyed steel during normalizing process was studied by physicochemical phase analysis and transmission electron microscopy（TEM）. The effect of precipitation behavior on mechanical properties was investigated by theoretical calculations. The results showed that 32.9% of V（C,N） precipitates remained undissolved in the austenite during the soaking step of the normalizing process. These precipitates prevented the growth of the austenite grains. During the subsequent cooling process, the dissolved V（C,N） re-precipitated and played a role in precipitation strengthening. The undissolved V（C,N） induced intragranular ferrite nucleation and refined the ferrite grains. Consequently, compared with hot-rolled steel, the normalized steel exhibited increased grain-refining strengthening but diminished precipitation strengthening, leading to an improvement of the impact energy at the expense of about 40 MPa yield strength.

关键词： normalizing V-N microalloyed steel precipitation strengthening grain-refining strengthening

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Polymorphism of Exon 2 of FSHβ Gene and Its Relationship with Reproduction Performance in Two Goat Breeds

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Agricultural Sciences in China 2010年第6期9卷 880-886页

作者： AN Xiao-peng HAN Dan HOU jin-xing LI guang wang Ya-na LI Ling ZHU guang-qin wang Jian-gang SONG Yu-xuan CAO Bin-yun College of Animal Science and Technology Northwest Agriculture and Forestry University Yangling 712100 P..R.China

The objectives of the present study were to detect the polymorphism in follicle stimulating hormone beta （FSHβ） gene and investigate the relationship between FSHβ gene and high prolificacy in *** to the sequence of ovine FSHβ gene,two pairs of primers were designed to detect single nucleotide polymorphism of exon 2 of FSHβ gene in two goat breeds,Xinong Saanen dairy goat and Boer goat,by *** least square mean and genetic variance of different genotypes at polymorphic locus were analyzed,and the selection reaction was forecasted by genetic correlation between marker locus and genetic variance of litter size *** was one polymorphic locus occurring in exon 2 （P2） with three genotypes （EE,EF and FF）.In Xinong Saanen dairy goat,EE genotype had significantly higher （P 〈 0.05） litter size than EF and FF genotype in the first to fourth parity and average parity;EF genotype had significantly higher （P 〈 0.05） litter size than FF genotype in the second and average *** Boer goat,EE genotype had significantly higher （P 〈 0.01） litter size than EF and FF genotype in the second to fourth parity and average parity;EF genotype had significantly higher （P 〈 0.05） litter size than FF genotype in average *** Xinong Saanen dairy and Boer goat,the heredity of litter size was mainly influenced by genetic additive effect and the EE genotype is a favorable marker genotype for litter size in these two breeds.

关键词： goat FSHβ polymorphism litter size

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A Novel Method for Forecasting Freak Wave Occurrence in A Short Crested Coastal Sea

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China Ocean Engineering 2024年第1期38卷 104-116页

作者： wang Ying-guang State Key Laboratory of Ocean Engineering Shanghai Jiao Tong UniversityShanghai 200240China School of Ocean and Civil Engineering Shanghai Jiao Tong UniversityShanghai 200240China

In order to forecast the distribution of crest amplitudes and the occurrence of freak waves in a short crested coastal sea,a novel transformed linear simulation method is initially proposed in this paper.A Hermite transformation model expressed as a monotonic cubic polynomial serves as the foundation for the novel simulation *** wave crest amplitude exceedance probabilities of two sea states-one with a directional wave spectrum based on the measured wave elevation data at the Yura coast and the other with a typical directional JONSWAP wave spectrum-have been predicted using the novel simulation method that has been *** likelihood that a particular critical wave crest amplitude will be exceeded is directly correlated with the probability that freak waves will *** is shown that the novel simulation approach suggested can provide predictions that are more precise than those obtained from the Rayleigh crest amplitude distribution model,the Jahns and Wheeler crest amplitude distribution model,or the conventional linear simulation *** study also demonstrated that the nonlinear simulation method is less effective than the novel simulation method in terms of efficiency.

关键词： wave crest amplitude freak waves short crested sea transformed linear simulation

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Effect of intravariceal sclerotherapy combined with esophageal mucosal sclerotherapy using small-volume sclerosant for cirrhotic patients with high variceal pressure

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World Journal of Gastroenterology 2015年第9期21卷 2800-2806页

作者： De-Run Kong jin-guang wang Chen Chen Fang-Fang Yu Qiong Wu Jian-Ming Xu Department of Gastroenterology the First Affiliated Hospital of Anhui Medical University

AIM:To explore the effect of intravariceal-mucosal sclerotherapy using small dose of sclerosant on the recurrence of esophageal ***:We randomly assigned 38 cirrhotic patients with previous variceal bleeding and high variceal pressure(> 15.2 mm Hg) to receive endoscopic variceal ligation(EVL) and combined intravariceal and esophageal mucosal sclerotherapy(combined group) using small-volume *** end-points of the study were rebleeding and recurrence of esophageal ***:During a median follow-up period of 16 mo,varices recurred in 1 patient in the combined group as compared with 7 patients in the EVL group(P =0.045).Rebleeding occurred in 3 patients in the EVL group as compared with 1 patient in the combined group(P=0.687).No patient died in the two *** significant differences were observed between the two groups with respect to serious adverse ***:Intravariceal-mucosal sclerotherapy using small dose of sclerosant is more effective than EVL in decreasing the incidence of variceal recurrence for cirrhotic patients.

关键词： Variceal bleeding Endoscopic variceal ligation End

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Static recrystallization behaviors and mechanisms of 7Mo super-austenitic stainless steel with undissolved sigma precipitates during double-stage hot deformation

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Journal of Iron and Steel Research International 2024年第2期31卷 475-487页

作者： Shi-guang Xu jin-shan He Run-ze Zhang Fu-cheng Zhang Xi-tao wang Collaborative Innovation Center of Steel Technology University of Science and Technology BeijingBeijing100083China State Key Laboratory of Metastable Materials Science and Technology Yanshan UniversityQinhuangdao066004HebeiChina Shandong Provincial Key Laboratory for High Strength Lightweight Metallic Materials Advanced Materials InstituteQilu University of Technology(Shandong Academy of Science)Jinan250353ShandongChina

Static recrystallization(SRX)behaviors and corresponding recrystallization mechanisms of 7Mo super-austenitic stainless steel were studied under different deformation *** order of influence of deformation parameters on static recrystallization behaviors,from high to low,is followed by temperature,first-stage strain and strain ***,the effect of holding time on static recrystallization behaviors is significantly controlled by *** addition,with the increase in temperature from 1000 to 1200°C,the static recrystallization mechanism evolves from discontinuous static recrystallization and continuous static recrystallization(cSRX)to metadynamic recrystallization and cSRX,and finally to *** cSRX exists at all *** is because high stacking fault energy(56 mJ m−2)promotes the movement of dislocations,making the deformation mechanism of this steel is dominated by planar slip of *** undissolved sigma precipitates promote static recrystallization through particle-stimulated ***,small strain-induced precipitates at grain boundaries hinder the nucleation of conventional SRX and the growth of recrystallized grains,while the hindering effect decreases with the increase in temperature.

关键词： 7Mo super-austenitic stainless steel Double-stage hot deformation Conventional static recrystallization Metadynamic recrystallization Strain-induced precipitation

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Self-adaptive gas flow and phase change behaviors during hydrate exploitation by alternate injection of N_(2) and CO_(2)

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Petroleum Science 2024年第3期21卷 2120-2129页

作者： Bo-Jian Cao Yi-Fei Sun Hong-Nan Chen jin-Rong Zhong Ming-Long wang Ming wang Chang-Yu Sun guang-jin Chen State Key Laboratory of Heavy Oil Processing China University of PetroleumBeijing102249China School of Chemistry and Chemical Engineering Changsha University of Science&TechnologyChangsha410114HunanChina

Since hydrate resources play a part of the stratigraphic framework structure in sediments,establishing a safe and economic method for hydrates exploitation remains the primary challenge to this *** the proposed methods,the spontaneous displacement of CH_(4) from hydrate cages by CO_(2) seems to be a perfect mechanism to address gas production and CO_(2) storage,especially in today's strong demand for carbon reduction and replacing clean *** extensive lab researches,in the past decade,injecting a mixture of CO_(2) and small molecule gas has become a key means to enhance displacement efficiency and has great potential for ***,there is a lack of in-depth research on gas flow in the reservoir,while the injected gas always passes through low-saturated hydrate areas with high permeability and then occurs gas channel in a short term,finally resulting in the decreases in gas production efficiency and produced gas ***,we explored a new injection-production mode of alternate injection of N2 and CO_(2) in order to fully coordinate the advantages of N_(2) in enhanced hydrate decomposition and CO_(2) in solid storage and heat *** alternate"taking"and"storing"processes perfectly repair the problem of the gas channel,achieving self-regulation effect of CH_(4) recovery and CO_(2) *** 3-D experimental results show that compared to the mixed gas injection,CH_(4) recovery is increased by>50%and CO_(2) storage is increased by>70%.Additionally,this alternate injection mode presented a better performance in CH_(4) concentration of produced gas and showed outstanding N_(2) utilization ***,we analyzed its self-adaptive gas flow mechanism and proposed an application model of"one injection and multiple production".We look forward to this study accelerating the application of CO_(2)-CH_(4) replacement technology.

关键词： Hydrate Replacement CH_(4)recovery CO_(2)storage Reservoir remediation

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Geophysical prediction of organic matter abundance in source rocks based on geochemical analysis:A case study of southwestern Bozhong Sag,Bohai Sea,China

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Petroleum Science 2024年第1期21卷 31-53页

作者： Xiang wang guang-Di Liu Xiao-Lin wang jin-Feng Ma Zhen-Liang wang Fei-Long wang Ze-Zhang Song Chang-Yu Fan State Key Laboratory of Petroleum Resources and Prospecting China University of Petroleum(Beijing)Beijing102249China College of Geosciences China University of Petroleum(Beijing)Beijing102249China State Key Laboratory of Continental Dynamics Northwest UniversityXi'an710069ShaanxiChina Department of Geology Northwest UniversityXi'an710069ShaanxiChina CNOOC Tianjin Branch Company Tianjin300459China

The Bozhong Sag is the largest petroliferous sag in the Bohai Bay Basin,and the source rocks of Paleogene Dongying and Shahejie Formations were buried *** of the drillings were located at the structural high,and there were few wells that met good quality source rocks,so it is difficult to evaluate the source rocks in the study area precisely by geochemical analysis *** on the Rock-Eval pyrolysis,total organic carbon(TOC)testing,the organic matter(OM)abundance of Paleogene source rocks in the southwestern Bozhong Sag were evaluated,including the lower of second member of Dongying Formation(E_(3)d2L),the third member of Dongying Formation(E_(3)d_(3)),the first and second members of Shahejie Formation(E_(2)s_(1+2)),the third member of Shahejie Formation(E_(2)s_(3)).The results indicate that the E_(2)s_(1+2)and E_(2)s_(3)have better hydrocarbon generative potentials with the highest OM abundance,the E_(3)d_(3)are of the second good quality,and the E_(3)d2L have poor to fair hydrocarbon generative ***,the well logs were applied to predict TOC and residual hydrocarbon generation potential(S_(2))based on the sedimentary facies classification,usingΔlogR,generalizedΔlogR,logging multiple linear regression and BP neural network *** various methods were compared,and the BP neural network method have relatively better prediction *** on the pre-stack simultaneous inversion(P-wave impedance,P-wave velocity and density inversion results)and the post-stack seismic attributes,the three-dimensional(3D)seismic prediction of TOC and S_(2)was carried *** results show that the seismic near well prediction results of TOC and S_(2)based on seismic multi-attributes analysis correspond well with the results of well logging methods,and the plane prediction results are identical with the sedimentary facies map in the study *** TOC and S_(2)values of E_(2)s_(1+2)and E_(2)s_(3)are higher than those in E_(3)d_(3)and E_(3)d_(2)L,basicall

关键词： Total organic carbon(TOC) Residual hydrocarbon generation potential(S_(2)) Geophysical prediction Seismic attribute Bozhong Sag Bohai Bay Basin

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Optimizing mechanical properties of HIPS fabricated with low-cost desktop 3D printers:investigating the impact of process parameters

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Advances in Manufacturing 2024年第2期12卷 379-395页

作者： jin-Ting Xu guang-Wei Zhang Man-Man Chen School of Automotive Engineering Dalian University of TechnologyDalian116024People’s Republic of China

Recently,low-cost desktop three-dimensional(3D)printers,employing the fused deposition modeling(FDM)technique,have gained widespread ***,most users cannot test the strength of printed parts,and little information is available about the mechanical properties of printed high-impact polystyrene(HIPS)parts using desktop 3D *** this study,the user-adjustable parameters of desktop 3D printers,such as crisscross raster orientation,layer thickness,and infill density,were *** experimental plans were designed using the Box-Behnken method,and tensile,3-point bending,and compression tests were carried out to determine the mechanical responses of the printed *** prediction models of the process parameters were regressed to produce the optimal combination of process *** experimental results showcase that the crisscross raster orientation has significant effects on the flexural and compression strengths,but not on the tensile *** an increase in the layer thickness,the tensile,flexural,and compression strengths first decreased and then increased,reaching their minimum values at approximately 0.16 mm layer *** addition,they all increased with an increase of infill *** was demonstrated that when the raster orientation,layer thickness,and infill density were 13.08°/–76.92°,0.09 mm,and 80%,respectively,the comprehensive mechanical properties of the printed HIPS were *** results can help end-users of desktop 3D printers understand the effects of process parameters on the mechanical properties,and offer practical suggestions for setting proper printing parameters for fabricating HIPS parts.

关键词： Desktop three-dimensional(3D)printers Fused deposition modeling(FDM) High-impact polystyrene(HIPS) Process parameters

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Differentially private SGD with random features

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Applied Mathematics(A Journal of Chinese Universities) 2024年第1期39卷 1-23页

作者： wang Yi-guang GUO Zheng-chu Polytechnic Institute of Zhejiang University Zhejiang UniversityHangzhou 310015China School of Mathematical Sciences Zhejiang UniversityHangzhou 310058China

In the realm of large-scale machine learning,it is crucial to explore methods for reducing computational complexity and memory demands while maintaining generalization ***,since the collected data may contain some sensitive information,it is also of great significance to study privacy-preserving machine learning *** paper focuses on the performance of the differentially private stochastic gradient descent(SGD)algorithm based on random *** begin,the algorithm maps the original data into a lowdimensional space,thereby avoiding the traditional kernel method for large-scale data storage ***,the algorithm iteratively optimizes parameters using the stochastic gradient descent ***,the output perturbation mechanism is employed to introduce random noise,ensuring algorithmic *** prove that the proposed algorithm satisfies the differential privacy while achieving fast convergence rates under some mild conditions.

关键词： learning theory differential privacy stochastic gradient descent random features reproducing kernel Hilbert spaces

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