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Dynamic steric confinement effect expands the frontier of Cu-catalyzed asymmetric propargylic aminations

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Science China Chemistry 2024年第10期67卷 3181-3183页

作者： Peng Chen mao-mao Zhang Wen-jing Xiao Liang-Qiu Lu Engineering Research Center of Photoenergy Utilization for Pollution Control and Carbon Reduction Ministry of EducationCollege of ChemistryCentral China Normal UniversityWuhan 430079China Wuhan Institute of Photochemistry and Technology Wuhan 430082China State Key Laboratory for Oxo Synthesis and Selective Oxidation Lanzhou Institute of Chemical Physics(LICP)Chinese Academy of SciencesLanzhou 730000China School of Chemistry and Chemical Engineering Henan Normal UniversityXinxiang 453007China

Chiralα-tertiary amines and related azacycles are commonly found in many natural products,pharmaceuticals and agrochemicals[1].Copper-catalyzed asymmetric propargylic amination(APA)reactions have been established as a reliable method to access enantio-enriched propargylic amines,largely due to the seminal contribution of Nishibayashi et al.[2]and van Maarseveen et al.[3]in 2008.

关键词： catalyzed asymmetric amines

The posterior selection method for hyperparameters in regularized least squares method

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Control Theory and Technology 2024年第2期22卷 184-194页

作者： Yanxin Zhang jing Chen Yawen mao Quanmin Zhu School of Science Jiangnan UniversityWuxi214122JiangsuChina The Science and Technology on Near-Surface Detection Laboratory Wuxi214122JiangsuChina Department of Engineering Design and Mathematics University of the West of EnglandBristolBS161QYUK

The selection of hyperparameters in regularized least squares plays an important role in large-scale system identification. The traditional methods for selecting hyperparameters are based on experience or marginal likelihood maximization method, which are inaccurate or computationally expensive. In this paper, two posterior methods are proposed to select hyperparameters based on different prior knowledge (constraints), which can obtain the optimal hyperparameters using the optimization theory. Moreover, we also give the theoretical optimal constraints, and verify its effectiveness. Numerical simulation shows that the hyperparameters and parameter vector estimate obtained by the proposed methods are the optimal ones.

关键词： Regularization method Hyperparameter System identification Least squares algorithm

Alkaline zinc-based flow battery: chemical stability, morphological evolution, and performance of zinc electrode with ionic liquid

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Frontiers of Materials Science 2024年第1期18卷 113-121页

作者： Tianyong mao jing Dai Meiqing Xin Deliang Zeng Zhipeng Xie Jiangxi Province Key Laboratory of Power Batteries and Materials Jiangxi University of Science and TechnologyGanzhou 341000China

Zinc-based flow battery is an energy storage technology with good application prospects because of its advantages of abundant raw materials,low cost,and environmental *** chemical stability of zinc electrodes exposed to electrolyte is a very important issue for zinc-based *** paper reports on details of chemical stability of the zinc metal exposed to a series of solutions,as well as the relationship between the morphological evolution of zinc electrodes and their properties in an alkaline *** corrosion of zinc electrodes by the electrolyte will change their surface ***,we observed that chemical corrosion is not the main contributor to the evolution of zinc electrode surface morphology,but the main contributor is the Zn/Zn^(2+)electrode *** morphological evolution of zinc electrodes was controlled by using ionic liquids,1-ethyl-3-methylimidazolium acetate(EMIA),and 1-propylsulfonic-3-methylimidazolium tosylate(PSMIT),and the electrode performance was recorded during the morphological evolution *** was observed that the reversible change of zinc electrode morphology was accompanied by better electrode performance.

关键词： alkaline medium morphological evolution zinc-based flow battery new energy

Evaluating the relative importance of predictors in Generalized Additive Models using the *** R package

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Plant Diversity 2024年第4期46卷 542-546页

作者： Jiangshan Lai jing Tang Tingyuan Li Aiying Zhang Lingfeng mao College of Ecology and Environment Nanjing Forestry UniversityNanjing210037China Research Center of Quantitative Ecology Nanjing Forestry UniversityNanjing 210037China university of Chinese Academy of Sciences Beijing100049China Guangzhou Climate and Agro-meteorology Center Guangzhou 511430China Guangdong Ecological Meteorological Center Guangzhou 510640China

Generalized Additive Models(GAMs)are widely employed in ecological research,serving as a powerful tool for ecologists to explore complex nonlinear relationships between a response variable and ***,evaluating the relative importance of predictors with concurvity(analogous to collinearity)on response variables in GAMs remains a *** address this challenge,we developed an R package named *** calculates individual R^(2) values for predictors,based on the concept of'average shared variance',a method previously introduced for multiple regression and canonical *** these individual R^(2)s,which add up to the overall R^(2),researchers can evaluate the relative importance of each predictor within *** illustrate the utility of the *** package by evaluating the relative importance of emission sources and meteorological factors in explaining ozone concentration variability in air quality data from London,*** believe that the *** package will improve the interpretation of results obtained from GAMs.

关键词： Average shared variance Coefficient of determination Commonality analysis GAMs Hierarchical partitioning Individual R^(2)

Effect of rapid rehabilitation nursing on improving clinical outcomes in postoperative patients with colorectal cancer

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World Journal of Gastrointestinal Surgery 2024年第7期16卷 2119-2134页

作者： jing-Yan Song jing Cao Jian mao Jiang-Lian Wang Department of Nursing The First Affiliated Hospital of Chongqing Medical UniversityChongqing 400016China Department of Oncology The First Affiliated Hospital of Chongqing Medical UniversityChongqing 400016China Information Center The First Affiliated Hospital of Chongqing Medical UniversityChongqing 400016China Department of Oncology Yunyang County People's HospitalChongqing 400016China

BACKGROunD Surgical resection is the cornerstone treatment for colorectal *** rehabilitation care predicated on evidence-based medical theory aims to improve postoperative nursing care,subsequently reducing the physical and mental traumatic stress response and helping patients who undergo surgery recover *** To assess the effect of rapid rehabilitation care on clinical outcomes,including overall postoperative complications,anastomotic leaks,wound infections,and intestinal obstruction in patients with colorectal *** We searched the PubMed,Web of Science,Embase,Elsevier Science Direct,and Springer Link databases from January 1,2010,to January 1,2024,to screen eligible studies on rapid rehabilitation care among patients who underwent colorectal cancer *** were screened based on the inclusion and exclusion *** 5.4 software was used for statistical analysis of the *** Twelve studies were enrolled,which included 2420 *** results showed that rapid rehabilitation care decreased the incidence of overall postoperative complications(OR:0.44,95%CI:0.26–0.74,P=0.002),anastomotic leaks(OR:0.68,95%CI:0.41–1.12,P=0.13),wound infections(OR:0.45,95%CI:0.29–0.72,P=0.0007),and intestinal obstruction(OR:0.54,95%CI:0.34–0.86,P=0.01)compared to conventional *** trials and studies are needed to confirm these *** Rapid rehabilitation care decreased the occurrence of postoperative complications,anastomotic leaks,wound infections,and intestinal obstruction compared to conventional care in patients who underwent colorectal ***,promoting the application of rapid rehabilitation care in clinical practice cannot be overemphasized.

关键词： Rapid rehabilitation care Anastomotic leak Wound infection Intestinal obstruction Colorectal cancer

Endoscopic detection and diagnostic strategies for minute gastric cancer:A real-world observational study

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World Journal of Gastrointestinal Oncology 2024年第8期16卷 3529-3538页

作者： Xiao-Wei Ji Jie Lin Yan-Ting Wang jing-jing Ruan jing-Hong Xu Kai Song Jian-Shan mao Department of Gastroenterology The Second Affiliated HospitalZhejiang University School of MedicineHangzhou 310009Zhejiang ProvinceChina Department of Pathology The Second Affiliated HospitalZhejiang University School of MedicineHangzhou 310009Zhejiang ProvinceChina

BACKGROunD Minute gastric cancers(MGCs)have a favorable prognosis,but they are too small to be detected by endoscopy,with a maximum diameter≤5 *** To explore endoscopic detection and diagnostic strategies for *** This was a real-world observational *** endoscopic and clinicopathological parameters of 191 MGCs between January 2015 and December 2022 were retrospectively *** discoverable opportunity and typical neoplastic features were emphatically *** All MGCs in our study were of a single pathological type,97.38%(186/191)of which were differentiated-type *** light endoscopy(WLE)detected 84.29%(161/191)of MGCs,and the most common morphology of MGCs found by WLE was ***-band imaging(NBI)secondary observation detected 14.14%(27/191)of MGCs,and the most common morphology of MGCs found by NBI was *** three MGCs were detected by indigo carmine third *** a well-demarcated border lesion exhibited a typical neoplastic color,such as yellowish-red or whitish under WLE and brownish under NBI,MGCs should be *** proportion with high diagnostic confidence by magnifying endoscopy with NBI(ME-NBI)was significantly higher than the proportion with low diagnostic confidence and the only visible groups(94.19%>56.92%>32.50%,P<0.001).CONCLUSION WLE combined with NBI and indigo carmine are helpful for detection of MGCs.A clear demarcation line combined with a typical neoplastic color using nonmagnifying observation is sufficient for diagnosis of *** improves the endoscopic diagnostic confidence of MGCs.

关键词： Minute gastric cancer White light endoscopy Narrow-band imaging endoscopy Indigo carmine Magnifying endoscopy Detection Diagnosis

Numerical study of submerged bending vegetation under unidirectional flow

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Water Science and Engineering 2024年第1期17卷 92-100页

作者： Pei-pei Zhang Yi-qing Gong Ken Vui Chua Jie Dai jing-qiao mao College of Water Conservancy and Hydropower Engineering Hohai UniversityNanjing 210098China Institute of Water Science and Technology Hohai UniversityNanjing 210098China School of Engineering Cardiff UniversityCardiff CF243AAUK

Submerged vegetation commonly grows and plays a vital role in aquatic ecosystems,but it is also regarded as a barrier to the passing *** simulations of flow through and over submerged vegetation were carried out to investigate the effect of vegetation density on flow *** simulations were computationally set up to replicate flume experiments,in which vegetation was mimicked with flexible plastic *** fluid-structure interaction between flow and flexible vegetation was solved by coupling the two modules of the COMSOL *** cases with different vegetation densities were simulated,and the results were successfully validated against the experimental *** contours of the simulated time-averaged streamwise velocity and Reynolds stress were extracted to highlight the differences in mean and turbulent flow *** turbulence intensity was found to be more sensitive to vegetation density than the time-averaged *** developing length increased with the spacing between *** snapshots of the bending vegetation under instantaneous velocity and vorticity revealed that flexible vegetation responded to the effects of eddies in the shear layer by swaying *** first two rows of vegetation suffered stronger approaching flow and were prone to more streamlined *** addition,the origin of tip vortices was investigated via the distribution of *** results reveal the variation of flow properties with bending submerged vegetation and provide useful reference for optimizationofrestorationprojects.

关键词： Computational fluid dynamics Fluid-structure interaction Turbulence Flexible and submerged vegetation

Temperature/electric field induced photoluminescence-modulation effect in dysprosium-doped barium titanate ferroelectric ceramics

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Journal of Materiomics 2024年第5期10卷 1117-1125页

作者： Lei Xia Xiao Liu Zhan mao Yanbin Cai jing Zhu Jiyang Xie Wanbiao Hu Yunnan Key Laboratory of Electromagnetic Materials and Devices National Center for International Research on Photoelectric and Energy MaterialsSchool of Materials and EnergyYunnan UniversityKunming650091China Electron Microscopy Center Yunnan UniversityKunming650091China university of Science and Technology of China Hefei230026China

Lanthanide(Ln^(3+))based ferroelectric phosphors,with an integration of PL emission and ferroelectric effect,are unveiling an exciting realm of possibilities for multifunctional ferroelectric-optic ***,how the ferroelectric host enables the tuning on the PL emissions through modulating the local structure(e.g.,lattice site,symmetry,strains etc.)of the Ln^(3+)activator is not established *** this work,a luminescent-ferroelectric material,***^(3+)doped BaTiO_(3) ceramic(Ba_(1–x)Dy_(x)TiO_(3)(x=0–0.07),abbr:BTO:Dy^(3+)),was explored to address the aforementioned *** BTO:Dy^(3+)ceramics were synthesized by a solid-state reaction *** crystal structure,photoluminescence(PL)and electric properties(dielectric constant,ferroelectric hysteresis and piezoelectric hysteresis loop)were systematically *** BTO:Dy^(3+)ceramics show two predominant emission peaks,corresponding to the blue magnetic dipole transition(477 nm,4F_(7/2)→6H_(15/2))and yellow electric dipole transition(573 nm,4F_(7/2)→6H_(13/2)),the intensity ration of which can be modulated by the ferroelectric polarization that causes the slight lattice *** a polarization-emission modulation combining with the Dy3+doping could accelerate the color change,from yellow to blue,which is characterized to detect the phase transition,with a method and mechanism were proposed,that is,the phase change is reflected by the PL characteristic peak intensity ***,the current results offer a convenient photoluminescence method for detecting the ferroelectric phase transition and a feasible approach to study the interaction between the photoluminescence and polarization in ferroelectric materials,for providing new insights for the development of multifunctional materials.

关键词： Photoluminescence Barium titanate Modulation Ferroelectric ceramics

Early systemic anticoagulation reduces hospital readmission in acute necrotizing pancreatitis patients:A retrospective cohort study

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Hepatobiliary & Pancreatic Diseases International 2024年第1期23卷 77-82页

作者： Wen-Jian mao jing Zhou Guo-Fu Zhang Fa-Xi Chen jing-Zhu Zhang Bai-Qiang Li Lu Ke Wei-Qin Li Department of Critical Care Medicine Jinling HospitalNanjing Medical UniversityNanjing 210002China Department of Critical Care Medicine Jinling HospitalMedical School of Nanjing UniversityNanjing 210002China National Institute of Healthcare Data Science Nanjing UniversityNanjing 210010China

Background:Early systemic anticoagulation(SAC)is a common practice in acute necrotizing pancreatitis(ANP),and its impact on in-hospital clinical outcomes had been ***,whether it affects long-term outcomes is *** study aimed to evaluate the effect of SAC on 90-day readmission and other long-term outcomes in ANP ***:During January 2013 and December 2018,ANP patients admitted within 7 days from the onset of abdominal pain were *** primary outcome was 90-day readmission after *** proportional-hazards regression model and mediation analysis were used to define the relationship between early SAC and 90-day ***:A total of 241 ANP patients were enrolled,of whom 143 received early SAC during their hospitalization and 98 did *** who received early SAC experienced a lower incidence of splanchnic venous thrombosis(SVT)[risk ratio(RR)=0.40,95%CI:0.26-0.60,Punders with a hazard ratio of 0.57(95%CI:0.34-0.96,P=0.04).Mediation analysis showed that SVT mediated 37.0%of the early SAC-90-day readmission ***:The application of early SAC may reduce the risk of 90-day readmission in the survivors of ANP patients,and reduced SVT incidence might be the primary contributor.

关键词： Anticoagulation Splanchnic venous thrombosis Acute necrotizing pancreatitis Readmission Long-term outcomes