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Computers, Materials & Continua 2021年第2期66卷 1091-1120页

作者： Kyungsuk Jang gun jin yun Department of Aerospace Engineering Seoul National UniversitySeoul088262South Korea Institute of Advanced Aerospace Technology Seoul National UniversitySeoul08826South Korea

This paper first proposes a new self-learning data-driven methodology that can develop the failure criteria of unknown anisotropic ductile materials from the minimal number of experimental *** failure criteria of anisotropic ductile materials requires time-consuming tests and manual data *** proposed method can overcome such practical *** methodology is formalized by combining four ideas:1)The deep learning neural network(DLNN)-based material constitutive model,2)Self-learning inverse finite element(SELIFE)simulation,3)Algorithmic identification of failure points from the selflearned stress-strain curves and 4)Derivation of the failure criteria through symbolic regression of the genetic *** update and the algorithmic tangent operator were formulated in terms of DLNN parameters for nonlinear finite element ***,the SELIFE simulation algorithm gradually makes the DLNN model learn highly complex multi-axial stress and strain relationships,being guided by the experimental boundary *** the failure point identification,a self-learning data-driven failure criteria are eventually developed with the help of a reliable symbolic regression *** methodology and the self-learning data-driven failure criteria were verified by comparing with a reference failure criteria and simulating with different materials orientations,respectively.

关键词： Data-driven modeling deep learning neural networks genetic programming anisotropic failure criterion

Prediction of Melt Pool Dimension and Residual Stress Evolution with Thermodynamically-Consistent Phase Field and Consolidation Models during Re-Melting Process of SLM

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Computers, Materials & Continua 2021年第1期66卷 87-112页

作者： Kang-Hyun Lee gun jin yun Department of Aerospace Engineering Seoul National UniversitySeoul08826South Korea Institute of Advanced Aerospace Technology Seoul National UniversitySeoul08826South Korea

Re-melting process has been utilized to mitigate the residual stress level in the selective laser melting(SLM)process in recent ***,the complex consolidation mechanism of powder and the different material behavior after the first laser melting hinder the direct implementation of the re-melting *** this work,the effects of re-melting on the temperature and residual stress evolution in the SLM process are investigated using a thermo-mechanically coupled finite element *** degree of consolidation is incorporated in the energy balance equation based on the thermodynamically-consistent phase-field *** drastic change of material properties due to the variation of temperature and material state is also *** the proposed simulation framework,the single-track scanning is simulated first to predict the melt pool dimension and validate the proposed model with the existing experimental *** obtained thermal histories reveal that the highest cooling rate is observed at the end of the local solidification time which acts as an important indicator for the alleviation of temperature ***,the scanning of a whole single layer that consists of multiple tracks is simulated to observe the stress evolution with several re-melting *** the full melting of powder material in the first scanning process,the increase of residual stress level is observed with one remelting ***,the predicted stress level with the re-melting process shows the variation trend attributable to the accumulated heat in the *** numerical issues and the detailed implementation process are also introduced in this paper.

关键词： Selective laser melting thermo-mechanical analysis Ti-6Al-4V additive manufacturing re-melting residual stress

Trinuclear gold-catalyzed site-selective alkylation of peptides

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Science China Chemistry 2025年第01期 249-256页

作者： Qing-yun Fang Chengyihan Gu Yinghan Chen Wencheng Yan Yong Liang Weipeng Li Chengjian Zhu Jie Han jin Xie State Key Laboratory of Coordination Chemistry Jiangsu Key Laboratory of Advanced Organic Materials Chemistry and Biomedicine Innovation Center (Chem BIC) School of Chemistry and Chemical Engineering Nanjing University Green Catalysis Center College of Chemistry Zhengzhou University State Key Laboratory of Natural Medicines China Pharmaceutical University

Selective modification of peptides has always been a challenging issue. The selective alkylation of peptides can alter the biological activity and physical properties of molecules, and it has gained significant research interest. We herein disclose an intriguing gold-catalyzed alkylation of peptides using bench-stable unactivated alkyl bromides under photoredox catalysis. A wide range of structurally diverse primary, secondary and tertiary alkyl bromides serve as effective coupling partners to precisely connect with the α-C(sp3)–H in glycine residue of peptides. This protocol demonstrates an exceptionally broad scope for alkyl halides and excellent tolerance for a wide range of useful functional groups. A series of relay transformations to construct cyclic peptides, to proceed click reaction and to realize peptide fluorescence labeling further enhance its synthetic practicality. In addition, mechanistic studies and density functional theory(DFT) calculations reveal an inner-sphere and subsequent outersphere single electron transfer(SET) mechanism.

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Maternal and fetal death associated with acute pancreatitis during pregnancy:A case report

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World Journal of Clinical Cases 2025年第10期13卷 53-58页

作者： jin Li Qing-Yan Zhang Mei-Hong Zhang Shan-yun Jiang Department of Anesthesiology Kaihua County People’s HospitalQuzhou 324300Zhejiang ProvinceChina Center for Clinical Inspection and Quarantine Kaihua County Center for Clinical Inspection and QuarantineQuzhou 324300Zhejiang ProvinceChina

BACKGROUND Acute pancreatitis in pregnancy is a rare but serious condition that can lead to high maternal mortality and fetal *** of pregnancy complicated by severe acute pancreatitis,particularly with subsequent respiratory and cardiac arrest,are rarely *** SUMMARY We present the case of a 35-year-old woman,at 36+5 weeks of gestation,who presented with paroxysmal epigastric pain accompanied by low back pain,nausea,and *** to the clinical symptoms,B-ultrasound imaging and biochemical indicators,the patient was diagnosed with acute pancreatitis and initially managed ***,3 hours after admission,the patient experienced respiratory and cardiac arrest,and the fetus *** this case,the adverse outcomes occurred due to the lack of aggressive fluid resuscitation and an active surgical *** Implementing aggressive fluid resuscitation to sustain tissue perfusion,alongside the proactive evaluation of pharmacological agents that suppress gastric acid secretion and inhibit pancreatic enzyme activity,may be beneficial in mitigating the risk of a severely adverse *** management of acute pancreatitis during pregnancy requires careful timing of surgical intervention,a thorough evaluation of the risks and benefits regarding the continuation or termination of pregnancy,and a focus on safeguarding both maternal and fetal health.

关键词： Severe acute pancreatitis Pregnancy Cardiac arrest Fetal death Case report

Kangfuxin solution alleviates esophageal stenosis after endoscopic submucosal dissection:A natural ingredient strategy

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World Journal of Gastroenterology 2025年第1期31卷 110-125页

作者： Xin Zhou Dan Ma Yi-Xiang He jing jin Hong-Lian Wang yun-Feng Wang Fan Yang Jian-Qin Liu Jie Chen Zhi Li Department of Spleen and Stomach Diseases the Affiliated Traditional Chinese Medicine HospitalSouthwest Medical UniversityLuzhou 646000Sichuan ProvinceChina The Key Laboratory of Integrated Traditional Chinese and Western Medicine for Prevention and Treatment of Digestive System Diseases of Luzhou City The Affiliated Traditional Medicine HospitalSouthwest Medical UniversityLuzhou 646000Sichuan ProvinceChina Department of Gastroenterology Changhai HospitalNaval Medical UniversityShanghai 20082China Research Center of Integrated Chinese and Western Medicine The Affiliated Traditional Chinese Medicine HospitalSouthwest Medical UniversityLuzhou 646000Sichuan ProvinceChina School of Integrated Traditional Chinese and Western Clinical Medicine North Sichuan Medical CollegeNanchong637100Sichuan ProvinceChina

BACKGROUND Esophageal stricture ranks among the most significant complications following endoscopic submucosal dissection(ESD).Excessive fibrotic repair is a typical pathological feature leading to stenosis after *** To examine the effectiveness and underlying mechanism of Kangfuxin solution(KFX)in mitigating excessive fibrotic repair of the esophagus *** Pigs received KFX at 0.74 mL/kg/d for 21 days after esophageal full circumferential *** examinations occurred on days 7 and 21 *** vitro,recombinant transforming growth factor(TGF)-β1(5 ng/mL)induced a fibrotic microenvironment in primary esophageal fibroblasts(pEsF).After 24 hours of KFX treatment(at 1.5%,1%,and 0.5%),expression ofα-smooth muscle actin-2(ACTA2),fibronectin(FN),and type collagen I was *** signaling was analyzed,including TGF-β1,Smad2/3,and phosphor-smad2/3(p-Smad2/3).RESULTS Compared to the Control group,the groups treated with KFX and prednisolone exhibited reduced esophageal stenosis,lower weight loss rates,and improved food tolerance 21 d after *** treatment,Masson staining revealed thinner and less dense collagen fibers in the submucosal ***,the expression of fibrotic effector molecules was notably ***,KFX downregulated the transduction levels of fibrotic functional molecules such as TGF-β1,Smad2/3,and p-Smad2/*** vitro,pEsF exposed to TGF-β1-induced fibrotic microenvironment displayed increased fibrotic activity,which was reversed by KFX treatment,leading to reduced activation of ACTA2,FN,and collagen *** 1.5%KFX treatment group showed decreased expression of p-Smad 2/3 in TGF-β1-activated *** KFX showed promise as a therapeutic option for post-full circumferential esophageal ESD strictures,potentially by suppressing fibroblast fibrotic activity through modulation of the TGF-β1/Smads signaling pathway.

关键词： Kangfuxin solution Natural component Endoscopic submucosal dissection Esophagus stricture Fibrosis

Effects of ultrasonic-assisted extraction on bioactive compounds,volatile flavors and antioxidant activities of vine tea water extracts

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Traditional Medicine Research 2025年第1期10卷 73-81页

作者： Xiao-Long Zhou Wei-jin Jiang Ji Yu Mao-Jun Yao yun-Tong Li Hunan Provincial Key Laboratory of Research Resource Mining and High-valued Utilization on Edible&Medicinal PlantCollege of Chemistry and Chemical EngineeringJishou UniversityJishou 416000China Hunan Gaoge Dairy Co. Ltd.Changsha 410000China

Background:Ampelopsis grossedentata,vine tea,which is the tea alternative beverages in *** vine tea processing,a large amount of broken tea is produced,which has low commercial ***:This study investigates the influence of different extraction methods(room temperature water extraction,boiling water extraction,ultrasonic-assisted room temperature water extraction,and ultrasonic-assisted boiling water extraction,referred to as room temperature water extraction(RE),boiling water extraction(BE),ultrasonic assistance at room temperature water extraction(URE),and ultrasonic assistance in boiling water extraction(UBE))on the yield,dihydromyricetin(DMY)content,free amino acid composition,volatile aroma components,and antioxidant properties of vine tea ***:A notable influence of extraction temperature on the yield of vine tea extracts(P<0.05),with BE yielding the highest at 43.13±0.26%,higher than that of RE(34.29±0.81%).Ultrasound-assisted extraction significantly increased the DMY content of the extracts(P<0.05),whereas DMY content in the RE extracts was 59.94±1.70%,that of URE reached 66.14±2.78%.Analysis revealed 17 amino acids,with L-serine and aspartic acid being the most abundant in the extracts,nevertheless ultrasound-assisted extraction reduced total free amino acid *** chromatography-mass spectrometry analysis demonstrated an increase in the diversity and quantity of compounds in the vine tea water extracts obtained through ultrasonic-assisted ***,69 and 68 volatile compounds were found in URE and UBE extracts,which were higher than the number found in RE and BE *** vitro,antioxidant activity assessments revealed varying antioxidant capacities among different extraction methods,with RE exhibiting the highest DPPH scavenging rate,URE leading in ABTS•+free radical scavenging,and BE demonstrating superior ferric ion reducing antioxidant ***:The findings suggest that extraction methods signi

关键词： vine tea dihydromyricetin ultrasonic-assisted extraction volatile aroma components

Activin A receptor type 1C single nucleotide polymorphisms associated with esophageal squamous cell carcinoma risk in Chinese population

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World Journal of Gastrointestinal Oncology 2025年第1期17卷 39-51页

作者： Si-yun Lin Hou Huang jin-Jie Yu Feng Su Tian Jiang Shao-Yuan Zhang Lu Lv Tao Long Hui-Wen Pan Jun-Qing Qi Qiang Zhou Wei-Feng Tang Guo-Wen Ding Li-Ming Wang Li-Jie Tan Jun Yin Department of Thoracic Surgery Zhongshan Hospital Affiliated to Fudan UniversityShanghai 200032China Shanghai Key Laboratory of Clinical Geriatric Medicine Huadong Hospital Affiliated to Fudan UniversityShanghai 200040China Department of Cardiothoracic Surgery The Affiliated People's Hospital of Jiangsu UniversityZhenjiang 212002Jiangsu ProvinceChina Department of Thoracic Surgery Sichuan Cancer Hospital&InstituteChengdu 610042Sichuan ProvinceChina Department of Cardiothoracic Surgery Nanjing Drum Tower HospitalThe Affiliated Hospital of Nanjing University Medical SchoolNanjing 210000Jiangsu ProvinceChina Department of Respiratory and Critical Care Medicine Shanghai Xuhui Central HospitalShanghai 200032China

BACKGROUND Transforming growth factor-β(TGF-β)superfamily plays an important role in tumor progression and *** A receptor type 1C(ACVR1C)is a TGF-βtype I receptor that is involved in tumorigenesis through binding to dif-ferent *** To evaluate the correlation between single nucleotide polymorphisms(SNPs)of ACVR1C and susceptibility to esophageal squamous cell carcinoma(ESCC)in Chinese Han *** In this hospital-based cohort study,1043 ESCC patients and 1143 healthy controls were *** SNPs(rs4664229,rs4556933,rs77886248,rs77263459,rs6734630)of ACVR1C were assessed by the ligation detection reaction ***-Weinberg equilibrium test,genetic model analysis,stratified analysis,linkage disequi-librium test,and haplotype analysis were *** Participants carrying ACVR1C rs4556933 GA mutant had significantly decreased risk of ESCC,and those with rs77886248 TA mutant were related with higher risk,especially in older male *** the haplotype analysis,ACVR1C Trs4664229Ars4556933Trs77886248Crs77263459Ars6734630 increased risk of ESCC,while Trs4664229Grs4556933Trs77886248Crs77263459Ars6734630 was associated with lower susceptibility to *** ACVR1C rs4556933 and rs77886248 SNPs were associated with the susceptibility to ESCC,which could provide a potential target for early diagnosis and treatment of ESCC in Chinese Han population.

关键词： Activin A receptor type 1C Single nucleotide polymorphisms Esophageal squamous cell carcinoma Genetic susceptibility Hospital-based cohort study

Characteristics of and risk factors for colorectal neoplasms in young adults in a screening population

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World Journal of Gastroenterology 2016年第10期22卷 2981-2992页

作者： Seung Eun Lee Hee Bum Jo Won gun Kwack yun jin Jeong Yeo-jin Yoon Hyoun Woo Kang Department of Internal Medicine Dongguk University Ilsan HospitalCollege of Medicine

AIM: To investigate prevalence and risk factors for colorectal neoplasms in adults aged < 50 years, for whom screening is not ***: This cross-sectional study compared prevalence and characteristics of colorectal and advanced adenomas in patients aged < 50 years who underwent colonoscopy screening with subjects aged ≥ 50 years. To evaluate risk factors for colorectal and advanced adenoma in young adults, we used multivariable logistic regression models. Colorectal neoplasm characteristics were evaluated and compared with those in older ***: Among 2819 patients included, prevalences of colorectal adenoma and advanced adenoma were 19.7% and 1.5%, respectively. As patient age increased, so did the prevalence of colorectal neoplasm. However, prevalence of advanced adenoma did not differ between age-groups 45-49 years and ≥ 50 years(OR = 0.43, 95%CI: 0.17-1.07, P = 0.070). In younger age-group(< 50 years), colorectal adenoma was significantly associated with older age, waist circumference(OR = 1.72, 95%CI: 1.15-2.55, P = 0.008), and current smoking(OR = 1.60, 95%CI: 1.07-2.41, P = 0.023). Alcohol consumption was an independent risk factor for colorectal advanced adenoma(OR = 3.69, 95%CI: 1.08-12.54, P = 0.037). Multiple neoplasms and large neoplasms(≥ 1 cm) were more prevalent in subjects ≥ 50 ***: Current screening strategies for colorectal cancer may need to be amended to account for patient age, especially in young subjects with abdominal obesity, current smoking and alcohol consumption.

关键词： Colorectal adenoma Advanced adenoma Colorectal cancer Cancer screening Young patients

DIRECT ITERATIVE METHODS FOR RANK DEFICIENT GENERALIZED LEAST SQUARES PROBLEMS

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Journal of Computational Mathematics 2000年第4期18卷 439-448页

作者： jin-yun Yuan Xiao-qing jin Departamento de Matematica Universidade Federal do ParanaCuritibaBrazil Faculty of Science and Technology University of MacaoMacaoChina

The generalized least squares (LS) problem ... (Ax - b)[sup TW[sup -1](Ax - b) appears in, many application areas. Here W is an m × m symmetric positive definite matrix and A is an m × n matrix with m ≥ n. Since the problem has many solutions in rank deficient case, some special preconditioned techniques are adapted to obtain the minimum 2-norm solution. A block SOR method and the preconditioned conjugate gradient (PCG) method are proposed here. Convergence and optimal relaxation parameter for the block SOR method are studied. An error bound for the PCG method is given. The comparison of these methods is investigated. Some remarks on the implementation of the methods and the operation cost are given as well. [ABSTRACT FROM AUTHOR]

关键词： rank deficient generalized LS problem block SOR method PCG method convergence optimal parameter

CaH2-promoted activity of Ni-carbonate interface for CO2 methanation

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Journal of Energy Chemistry 2025年第01期 522-532页

作者： jin-Peng Wang Guo-Cui Mao Hui-Lin Jiang Bao-Xia Dong yun-Lei Teng School of Chemistry and Chemical Engineering Yangzhou University

Transition metal-carbonate interfaces often act as active sites in heterogeneous catalytic *** interface between transition metal and metal carbonate exhibits a dynamic equilibrium during the CO2hydrogenation reaction,involving surface carbonate hydrogenation and ***,there have been few reports on engineering the activity of the interface between transition metal and alkaline earth metal carbonate for catalytic *** work demonstrated that the incorporation of CaH2in Ni/CaCO3enhances the CO2methanation activity of the *** CO2conversion for Ni/CaH2-CaCO3reached 68.5%at 400°C,which was much higher than that of the Ni/CaCO3（31.6%） and Ni/CaH2-CaO （42.4%） ***,the Ni/CaH2-CaCO3catalysts remained stable during the stability test for 24 h at 400°C and 8 *** research revealed that CaH2played a crucial role in promoting the activity of the Ni-carbonate interface for ***2could modify the electronic structure of Ni and tune the structural properties of CaCO3to generate medium basic sites （OH groups）,which are favorable for the activation of H2and ***-situ Fourier transform infrared spectroscopy （FTIR） analysis combined with density functional theory calculations demonstrated that CO2activation occurs at the hydroxyl group （OH） on the CaH2-modified Ni-carbonate surface,leading to the formation of CO3H****,our study has confirmed that CO2methanation over the Ni/CaH2-CaCO3catalysts proceeds via the formate pathway.

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