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A comprehensive research on wear resistance of GH4169 superalloy in longitudinal-torsional ultrasonic vibration side milling with tool wear and surface quality

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Chinese Journal of Aeronautics 2024年第4期37卷 556-573页

作者： Baoqi CHANG Zhaoxi YI fen ZHANG Lian DUAN Ji-an DUAN School of Mechanical and Electrical Engineering Central South UniversityChangsha 410083China State Key Laboratory of High Performance and Complex Manufacturing Central South UniversityChangsha 410083China School of Physics and Electronics Central South UniversityChangsha 410083China

To improve the service and machining performance of the workpiece, the tool wear mechanisms, surface machining quality, and wear resistance in conventional side milling(CSM)and longitudinal-torsional ultrasonic vibration side milling(LTUVSM) of GH4169 superalloy at different cutting lengths are investigated systematically. Tool wear mechanisms are revealed and the correlation between machined surface quality with tool wear is analyzed correspondingly. Tool wear patterns mainly include adhesive wear, diffusion wear, abrasive wear, and chipping *** surface quality is achieved in LTUVSM due to a maximum reduction of flank wear bandwidth and wear rate by 71.9% and 71.5%, respectively, compared to CSM. The friction coefficient,initial wear stage time, and wear volume of dry sliding wear were measured to evaluate the workpiece wear resistance. The maximum reductions in friction coefficient and wear volume in LTUVSM are 18.2% and 15.8% compared to CSM. The regular ultrasonic vibration textures suppress the friction and the growth of contact nodes in the contact area, decreasing the degree of surface wear, which is demonstrated by a 38.8% increase in initial wear stage time compared to *** conclusion, the workpiece in LTUVSM exhibits higher wear resistance because of the improvement of tool wear and the guarantee of surface quality.

关键词： Dry sliding wear Surface quality Tool wear Ultrasonic vibration Wear resistance

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Palladium-catalyzed multi components oxy-aminofluorination and aminofluorination of gem-difluoroalkenes

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Chinese Chemical Letters 2024年第2期35卷 420-425页

作者： fen Wu Xin Li Junbiao Chang Dachang Bai State Key Laboratory of Antiviral Drugs NMPA Key Laboratory for Research and Evaluation of Innovative DrugKey Laboratory of Green Chemical Media and ReactionsMinistry of EducationSchool of Chemistry and Chemical EngineeringPingyuan LaboratoryHenan Normal UniversityXinxiang 453007China State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032China

Organofluorine compounds are widely used in the realm of drug discovery and material ***,we developed palladium catalyzed intermolecular aminofluorination and oxy-aminofluorination of gem‑difluoroalkenes with N-fluorobenzenesulfonimide(NFSI),in which NFSI was used as the nitrogen source and *** reaction provides an efficient and straightforward synthesis route of a series ofα-trifluoromethyl benzylic ***,three/four components oxy-aminofluorination processes were realized to giveα-trifluoromethyl benzylic ether with a terminal amino group,which proceed through C(sp^(3))-O bond cleavage of easily available ether and simultaneous introduced a fluorine,an amino and an oxy substituent in one pot with excellent *** divergent reactivity not only included the incorporation of one ether molecular,but also much more challenged two ether insertion with excellent selectivity through succession C(sp^(3))-O bonds *** protocol allows for concise synthesis of high value amines with fluoroalkyl-substituents and selectively transformation of easily available ethers by high-valent palladium catalysis.

关键词： Palladium Multi components Aminofluorination Oxy-aminofluorination C(sp^(3))-O bond cleavage

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Fault Estimation for a Class of Markov Jump Piecewise-Affine Systems: Current Feedback Based Iterative Learning Approach

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IEEE/CAA Journal of Automatica Sinica 2024年第2期11卷 418-429页

作者： Yanzheng Zhu Nuo Xu fen Wu Xinkai Chen Donghua Zhou IEEE College of Electrical Engineering and Automation Shandong University of Science and TechnologyQingdao 266590China College of Mechanical Engineering and Automation Huaqiao UniversityXiamen 361021China Department of Mechanical and Aerospace Engineering North Carolina State UniversityRaleigh NC 27695 USA Department of Electronic and Information Systems Shibaura Institute of TechnologySaitama 337-8570Japan

In this paper, the issues of stochastic stability analysis and fault estimation are investigated for a class of continuoustime Markov jump piecewise-affine(PWA) systems against actuator and sensor faults. Firstly, a novel mode-dependent PWA iterative learning observer with current feedback is designed to estimate the system states and faults, simultaneously, which contains both the previous iteration information and the current feedback mechanism. The auxiliary feedback channel optimizes the response speed of the observer, therefore the estimation error would converge to zero rapidly. Then, sufficient conditions for stochastic stability with guaranteed performance are demonstrated for the estimation error system, and the equivalence relations between the system information and the estimated information can be established via iterative accumulating ***, two illustrative examples containing a class of tunnel diode circuit systems are presented to fully demonstrate the effectiveness and superiority of the proposed iterative learning observer with current feedback.

关键词： Current feedback fault estimation iterative learning observer Markov jump piecewise-affine system

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Preoperative prediction of lymphovascular and perineural invasion in gastric cancer using spectral computed tomography imaging and machine learning

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World Journal of Gastroenterology 2024年第6期30卷 542-555页

作者： Hui-Ting Ge Jian-Wu Chen Li-Li Wang Tian-Xiu Zou Bin zheng Yuan-fen Liu Yun-Jing Xue Wei-Wen Lin Department of Radiology Fujian Medical University Union HospitalFuzhou 350001Fujian ProvinceChina Fujian Key Laboratory of Intelligent Imaging and Precision Radiotherapy for Tumors Fujian Medical UniversityFuzhou 350001Fujian ProvinceChina Digestive Hematological and Breast MalignanciesClinical Research Center for Radiology and Radiotherapy of Fujian ProvinceFuzhou 350001Fujian ProvinceChina Department of Radiation Oncology Fujian Medical University Union HospitalFuzhou 350001Fujian ProvinceChina Department of Diagnostic Radiology Fujian Medical University Union HospitalFuzhou 350001Fujian ProvinceChina School of Electrical and Computer Engineering University of OklahomaOklahomaOK 73019United States

BACKGROUND Lymphovascular invasion(LVI)and perineural invasion(PNI)are important prognostic factors for gastric cancer(GC)that indicate an increased risk of metastasis and poor *** preoperative prediction of LVI/PNI status could help clinicians identify high-risk patients and guide treatment ***,prior models using conventional computed tomography(CT)images to predict LVI or PNI separately have had limited *** CT provides quantitative enhancement parameters that may better capture tumor *** hypothesized that a predictive model combining clinical and spectral CT parameters would accurately preoperatively predict LVI/PNI status in GC *** To develop and test a machine learning model that fuses spectral CT parameters and clinical indicators to predict LVI/PNI status *** This study used a retrospective dataset involving 257 GC patients(training cohort,n=172;validation cohort,n=85).First,several clinical indicators,including serum tumor markers,CT-TN stages and CT-detected extramural vein invasion(CT-EMVI),were extracted,as were quantitative spectral CT parameters from the delineated tumor ***,a two-step feature selection approach using correlation-based methods and information gain ranking inside a 10-fold cross-validation loop was utilized to select informative clinical and spectral CT parameters.A logistic regression(LR)-based nomogram model was subsequently constructed to predict LVI/PNI status,and its performance was evaluated using the area under the receiver operating characteristic curve(AUC).RESULTS In both the training and validation cohorts,CT T3-4 stage,CT-N positive status,and CT-EMVI positive status are more prevalent in the LVI/PNI-positive group and these differences are statistically significant(P<0.05).LR analysis of the training group showed preoperative CT-T stage,CT-EMVI,single-energy CT values of 70 keV of venous phase(VP-70 keV),and the ratio of standardized iodine co

关键词： Spectral computed tomography Gastric cancer Lymphovascular invasion Perineural invasion

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Neuroendocrine carcinoma of the common hepatic duct coexisting with distal cholangiocarcinoma:A case report and review of literature

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World Journal of Gastrointestinal Surgery 2024年第5期16卷 1449-1460页

作者： Fei Chen Wei-Wei Li Juan-fen Mo Min-Jie Chen Su-Hang Wang Shu-Ying Yang zheng-Wei Song Department of Hepatobiliary Surgery The Second Affiliated Hospital of Jiaxing UniversityJiaxing 314000Zhejiang ProvinceChina Graduate School Bengbu Medical CollegeBengbu 233000Anhui ProvinceChina The Key Laboratory The Second Affiliated Hospital of Jiaxing UniversityJiaxing 314000Zhejiang ProvinceChina Department of Pathology The Second Affiliated Hospital of Jiaxing UniversityJiaxing 314000Zhejiang ProvinceChina Department of Intensive Medicine The Second Affiliated Hospital of Jiaxing UniversityJiaxing 314000Zhejiang ProvinceChina

BACKGROUND Neuroendocrine carcinoma(NEC)of the extrahepatic bile duct is very rare,and the treatment and prognosis are ***,we report the case of a middleaged female with primary large cell NEC(LCNEC)of the common hepatic duct combined with distal cholangiocarcinoma(dCCA).Additionally,after a review of the relevant literature,we summarize and compare mixed neuroendocrine-nonneuroendocrine neoplasm(MiNEN)and pure NEC to provide a reference for selecting the appropriate treatment and predicting the prognosis of this rare *** SUMMARY A 62-year-old female presented to the hospital due to recurrent abdominal pain for 2 *** examination showed mild tenderness in the upper abdomen and a positive Courvoisier *** tests showed elevated liver transaminase and carbohydrate antigen 199 *** examination revealed node dissection was performed,and hepatic duct tumours were unexpectedly found during *** suggested poorly differentiated LCNEC(approximately 0.5 cm×0.5 cm×0.4 cm),Ki-67(50%),synaptophysin+,and chromogranin A+.dCCA pathology suggested moderately differentiated *** patient eventually developed lymph node metastasis in the liver,bone,peritoneum,and abdominal cavity and died 24 months after *** sequencing methods were used to compare gene mutations in the two primary bile duct *** The prognosis of MiNEN and pure NEC alone is different,and the selection of treatment options needs to be differentiated.

关键词： Neuroendocrine carcinoma Mixed neuroendocrine-non-neuroendocrine neoplasm Cholangiocarcinoma Extrahepatic bile duct Case report

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M2-like Kupffer cells in fibrotic liver may protect against acute insult

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World Journal of Gastroenterology 2017年第20期23卷 3655-3663页

作者： Qing-fen zheng Li Bai Zhong-Ping Duan Yuan-Ping Han Su-Jun zheng Yu Chen Jian-Sheng Li Department of Gastroenterology First Affiliated Hospital of Zhengzhou University Artificial Liver Center Beijing You An HospitalCapital Medical University Center for Growth Metabolism and AgingKey Laboratory for Bio-Resource and Eco-EnvironmentCollege of Life SciencesSichuan University National Key Laboratory of Biotherapy Sichuan University

AIM To investigate the mechanism of hepatoprotection conferred by liver fibrosis through evaluating the activation phenotype of kupffer *** Control and fibrotic mice were challenged with a lethal dose of D-Gal N/lipopolysaccharide(LPS),and hepatic damage was assessed by histology,serum alanine transferase(ALT)levels,and hepatic expression of HMGB1,a potent pro-inflammatory *** localization of F4/80(a surrogate marker of KCs),HMGB1,and type I collagen(Col-1)was determined by immunofluorescence *** phenotype of KCs was characterized by real-time *** isolated from control or fibrotic mice were challenged with LPS or HMGB1 peptide,and HMGB1 translocation was *** Liver fibrosis protected mice against D-Gal N/LPS challenge,as shown by improved hepatic histology and reduced elevation of ALT compared with the normal mice treated in the same *** hepatoprotection was also accompanied by inhibition of HMGB1 expression in the ***-localization of F4/80,HMGB1,and Col-1 was found in fibrotic livers,indicating the close relationship between KCs,HMGB1 and liver *** isolated from fibrotic mice predominantly exhibited an M2-like *** vitro experiments showed that HMGB1 was localized in the nucleus of the majority of M2-like KCs and that the translocation of HMGB1 was inhibited following stimulation with LPS or HMGB1 peptide,while both LPS and HMGB1 peptide elicited translocation of intranuclear HMGB1 in KCs isolated from the control *** M2-like Kupffer cells in fibrotic liver may exert a protective effect against acute insult by inhibiting the translocation of HMGB1.

关键词：肝纤维变性损害抵抗 Kupffer 房间激活高活动性的组盒子 1 Translocation

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Clinical prediction of insufficient vaults after implantable collamer lens implantation

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International Journal of Ophthalmology(English edition) 2024年第7期17卷 1300-1306页

作者： Jun Zhu Dan Cheng Xue-Ying Zhu fen-fen Li Ye Yang Yu-feng Ye National Clinical Research Center for Ocular Diseases Eye HospitalWenzhou Medical UniversityWenzhou 325027Zhejiang ProvinceChina

AIM:To determine the factors related to preoperative ocular characters that are predictive of insufficient vault(<250μm)after implantable collamer lens(ICL V4c;STAAR Surgical)***:The participants underwent ICL surgery and were divided into the low(<250μm)and normal(250-1000μm)vault groups based on the postoperative vault at *** preoperative biometric parameters and clinical outcomes were compared between the two *** relationship between the 3-month vault values and preoperative ocular parameters were evaluated by Generalized estimating ***:Sixteen(23 eyes)and 36 patients(63 eyes)were in the low and normal vault groups,*** implantation procedures were uneventful with no cataract formation in the early postoperative *** sulcusto-sulcus lens rise(STSL)and iris ciliary angle(ICA)were correlated with vault at 3mo after *** 0.1 mm increase in STSL was associated with 38.9μm decrease in the postoperative 3-month vault.A rise of 1 degree in ICA is associated with a reduction of 4μm in ***:Eyes with a narrow ciliary sulcus are associated with a higher rate of low vault after ICL implantation,suggesting a need for adjustments to the ICL size in these *** the characteristics of the ciliary sulcus contributes valuable information to predict low vault after surgery.

关键词： insufficient vault implantable collamer lens ciliary body posterior chamber

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修剪、断根和基质改良对三角梅叶片SPAD值的影响

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湖南农业科学 2024年第8期 20-22,28页

作者：郭沛楷温志傅小霞张丽华伍成厚郑育芬乐龙胜刘瑞霞广州市林业和园林科学研究院广东广州510405

为给天桥绿化三角梅的更新复壮提供参考,以上桥绿化10 a的小叶紫花三角梅为材料,采用正交试验探究了修剪、断根和基质改良对三角梅叶片SPAD值的影响。结果表明:正交试验的三角梅叶片SPAD值为46.4~55.5,试验30、73和120 d后不同处理间均... 详细信息

为给天桥绿化三角梅的更新复壮提供参考,以上桥绿化10 a的小叶紫花三角梅为材料,采用正交试验探究了修剪、断根和基质改良对三角梅叶片SPAD值的影响。结果表明:正交试验的三角梅叶片SPAD值为46.4~55.5,试验30、73和120 d后不同处理间均存在极显著差异;修剪强度对三角梅叶片SPAD值影响极显著,修剪73和120 d后,轻度修剪的SPAD值极显著高于中度和重度修剪;断根和基质改良均不能提高三角梅的叶片SPAD值。

关键词：三角梅修剪断根基质改良 SPAD值

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Health outcomes of electronic cigarettes

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中华医学杂志(英文版) 2024年第16期137卷 2024 Jul 8页

作者： Li Xinmeng Yuan Lingzhi Wang fen Department of Gastroenterology The Third Xiangya Hospital Central South University Changsha Hunan China Hunan Key Laboratory of Non-resolving Inflammation and Cancer The Third Xiangya Hospital Central South University Changsha Hunan China

The usage of electronic cigarettes (e-cigarettes) sparked an outbreak of unidentified vaping-related lung disease in the US during late 2019. With e-cigarettes becoming more and more popular, smokers have more options other than conventional cigarettes. Under these circumstances, a comprehensive evaluation of the general safety of new tobacco and tobacco-related products, represented by e-cigarettes, to human health is necessary. In this review, we summarize the current research on potential negative impacts of e-cigarette exposure on human health. In particular, studies detailing the relationship between e-cigarettes and the digestive system are summarized, with mechanisms mainly including hepatic metabolic dysfunction, impaired gut barrier, and worsened outcomes of inflammatory bowel disease (IBD). Although believed to be safer than traditional cigarettes, e-cigarettes exert adverse effects on systemic health and induce the development of multiple diseases including asthma, cardiovascular disease, and IBD. Moreover, nicotine-containing e-cigarettes have a negative impact on the childhood development and increase the risk of arterial stiffness compared to the non-nicotine e-cigarettes. However, non-nicotine e-cigarette components have detrimental effects including promoting liver damage and metabolic disorders.

关键词： Electronic cigarettes Electronic nicotine delivery system Smoking cessation Health promotion Tobacco harm reduction Smoker

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Diagnosis and treatment of biliary mucinous cystic neoplasms: A single-center experience

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Hepatobiliary & Pancreatic Diseases International 2024年第5期23卷 495-501页

作者： Jun-Jun Jia Ya-fen Cheng Mei-Bao feng Li Liu Ming-Qi Shuai Xiao-Dong Shen Xiao-feng Tang Shu-Sen zheng Division of Hepatobiliary and Pancreatic Surgery Department of Surgerythe First Affiliated HospitalZhejiang University School of MedicineHangzhou 310003China Department of International Healthcare Center the First Affiliated HospitalZhejiang University School of MedicineHangzhou 310003China Department of Pathology the First Affiliated HospitalZhejiang University School of MedicineHangzhou 310003China Department of Library the First Affiliated HospitalZhejiang University School of MedicineHangzhou 310003China

Background: Biliary mucinous cystic neoplasms(BMCNs) are rare hepatobiliary cystic tumors, which can be divided into noninvasive and invasive types. This study aimed to investigate the diagnosis, treatment, and prognosis of BMCNs in a large single center. Methods: We analyzed 49 patients with BMCNs confirmed by postoperative pathology at the First Afflliated Hospital, Zhejiang University School of Medicine between January 2007 and December 2021. Results: Among the 49 patients, 37 were female(75.5%), and the average age was 57.04 years. Common symptoms included abdominal discomfort, jaundice and fever, while 22 patients(44.9%) had no symptoms. Serum carbohydrate antigen(CA) 19-9 and CA125 concentrations were elevated in 34.8% and 19.6% of patients, respectively. Forty-eight patients had tumors in the intrahepatic bile ducts and only one had a tumor in the extrahepatic bile duct. Forty-eight patients with noninvasive intrahepatic BMCNs were further analyzed in terms of pathological features: 34(70.8%) had low-grade intraepithelial neoplasms(LGINs), and 14(29.2%) had high-grade intraepithelial neoplasms(HGINs). The potential immunohistochemical markers of BMCNs were cytokeratin(CK) 19, CK7, estrogen receptor and progesterone receptor. Follow-up data for 37 patients with intrahepatic BMCNs were obtained. The median overall survival(OS) of BMCNs was not reached. The longest survival time was 137 *** 5-and 10-year OS rates were 100% and 85.4%, respectively. The 5-and 10-year recurrence-free survival(RFS) rates were 93.9% and 80.2%, respectively. Conclusions: BMCNs are rare cystic neoplasms that commonly occur in middle-aged females. BMCNs can only be diagnosed and classified by postoperative pathology, as there are no specific clinical presentations, serological indicators or imaging modalities for preoperative diagnosis. Complete surgical resection is necessary for BMCNs, and the postoperative prognosis is favorable.

关键词： Biliary mucinous cystic neoplasms Low-grade intraepithelial neoplasms High-grade intraepithelial neoplasms Overall survival Recurrence-free survival

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