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Extended Lorenz majorization and frequencies of distances in an undirected network

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Journal of Data and Information Science 2024年第1期9卷 1-10页

作者： leo Egghe Hasselt University Diepenbeek 3590Belgium

Purpose:To contribute to the study of networks and ***/methodology/approach:We apply standard mathematical ***:We show that the distance distribution in an undirected network Lorenz majorizes the one of a *** a consequence,the average and median distances in any such network are smaller than or equal to those of a *** limitations:We restricted our investigations to undirected,unweighted *** implications:We are convinced that these results are useful in the study of small worlds and the so-called six degrees of separation ***/value:To the best of our knowledge our research contains new network results,especially those related to frequencies of distances.

关键词： majorization Lorenz curves networks shortest path distance graphs

维普期刊数据库

Enhanced Hoek-Brown(H-B)criterion for rocks exposed to chemical corrosion

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International Journal of Mining Science and Technology 2024年第5期34卷 609-630页

作者： Hao Li leo Pel Zhenjiang You David Smeulders Department of Mechanical Engineering Eindhoven University of TechnologyEindhoven 5600 MBthe Netherlands Department of Applied Physics Eindhoven University of TechnologyEindhoven 5600 MBthe Netherlands Center for Sustainable Energy and Resources School of EngineeringEdith Cowan UniversityJoondalupWA 6027Australia School of Chemical Engineering The University of QueenslandBrisbaneQLD 4072Australia Gas and Energy Transition Research Centre The University of QueenslandBrisbaneQLD 4072Australia

Underground constructions often encounter water environments,where water–rock interaction can increase porosity,thereby weakening engineering ***,the failure criterion for chemically corroded rocks becomes essential in the stability analysis and design of such *** study enhances the applicability of the Hoek-Brown(H-B)criterion for engineering structures operating in chemically corrosive conditions by introducing a kinetic porosity-dependent instantaneous mi(KPIM).A multiscale experimental investigation,including nuclear magnetic resonance(NMR),X-ray diffraction(XRD),scanning electron microscopy(SEM),pH and ion chromatography analysis,and triaxial compression tests,is employed to quantify pore structural changes and their linkage with the strength responses of limestone under coupled chemical-mechanical(C-M)*** employing ion chromatography and NMR analysis,along with incorporating the principles of free-face dissolution theory accounting for both congruent and incongruent dissolution,a kinetic chemical corrosion model is *** model aims to calculate the kinetic porosity alterations within rocks exposed to varying H+concentrations and ***,utilizing the generalized mixture rule(GMR),the kinetic porositydependent mi is *** of the KPIM-enhanced H-B criterion using compression test data from 5 types of rocks demonstrated a high level of consistency between the criterion and the experimental results,with a coefficient of determination greater than 0.96,a mean absolute percentage error less than 4.84%,and a root-mean-square deviation less than 5.95 ***,the physical significance of the porosity-dependent instantaneous mi is clarified:it serves as an indicator of a rock’s capacity to leverage the confining pressure effect.

关键词： Hoek-Brown(H-B)criterion Instantaneous mi Kinetic porosity-dependency Chemical corrosion Compressive strength

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Covid-19 vaccination in pregnancy and placental pathology

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Asian pacific Journal of Reproduction 2024年第2期13卷 76-79页

作者： leo Simanjuntak Department of Obstetrics and Gynecology Faculty of MedicineUniversitas HKBP NommensenMedanIndonesia

Objective:To describe and determine the association between Covid-19 vaccination in pregnancy and placental ***:Conducted in a tertiary hospital in Medan,Indonesia,from April 30th 2022 to June 30th 2022,this single-center cross-sectional study involved Covid-19 vaccinated and unvaccinated women with singleton full-term pregnancies delivering live fetuses via cesarean *** characteristics,placental pathologies,and the placental index were documented at *** association between Covid-19 vaccination status and placental pathology was ***:The study enrolled 200 pregnant women,including 110 vaccinated women and 90 unvaccinated *** significant differences were observed in birthweight(P=0.48),placental index(P=0.48),and placental pathology findings[intervillous bleeding(P=0.20),increased syncytial knots(P=0.83),chorangiosis(P=0.13),villous stromal edema(P=0.13),vascular dilation and congestion(P=0.13),and vascular wall thrombus(P=0.71)]between the vaccinated and unvaccinated ***:This study revealed no statistically significant association between Covid-19 vaccination and placental *** findings support the safety of Covid-19 vaccination during pregnancy,in regards to changes of the placental pathology.

关键词： Covid-19 Vaccination Pregnancy Women Placenta

Hyperparameter optimization of YOLOv8 for smoke and wildfire detection:Implications for agricultural and environmental safety

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Artificial Intelligence in Agriculture 2024年第2期12卷 109-126页

作者： leo Ramos Edmundo Casas Eduardo Bendek Cristian Romero Francklin Rivas-Echeverría Kauel Inc. Menlo Park(Silicon Valley)CA 94025USA Computer Vision Center Universitat Autònoma de BarcelonaBellaterra 08193Spain Faculty of Engineering University of DeustoBilbao 48007Spain Jet Propulsion Laboratory NASAPasadenaCA 91109USA

In this study,we extensively evaluated the viability of the state-of-the-art YOLOv8 architecture for object detec-tion tasks,specifically tailored for smoke and wildfire identification with a focus on agricultural and environmen-tal *** available versions of YOLOv8 were initially fine-tuned on a domain-specific dataset that included a variety of scenarios,crucial for comprehensive agricultural ***‘large’version(YOLOv8l)was se-lected for further hyperparameter tuning based on its performance *** model underwent a detailed hyperparameter optimization using the One Factor At a Time(OFAT)methodology,concentrating on key param-eters such as learning rate,batch size,weight decay,epochs,and *** from the OFAT study were used to define search spaces for a subsequent Random Search(RS).The final model derived from RS demon-strated significant improvements over the initial fine-tuned model,increasing overall precision by 1.39%,recall by 1.48%,F1-score by 1.44%,mAP@0.50 by 0.70%,and mAP@0.50:0.95 by 5.09%.We validated the enhanced model's efficacy on a diverse set of real-world images,reflecting various agricultural settings,to confirm its ro-bustness in detecting smoke and *** results underscore the model's reliability and effectiveness in scenar-ios critical to agricultural safety and environmental *** work,representing a significant advancement in the field of fire and smoke detection through machine learning,lays a strong foundation for fu-ture research and solutions aimed at safeguarding agricultural areas and natural environments.

关键词： Agricultural safety Wildfire detection Smoke detection Object detection Computer vision YOL

Removing Splitting/Modeling Error in Projection/Penalty Methods for Navier-Stokes Simulations with Continuous Data Assimilation

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Communications in Mathematical Research 2024年第1期40卷 1-29页

作者： Elizabeth Hawkins leo G.Rebholz Duygu Vargun Department of Mathematical Sciences Clemson UniversityClemsonSC 29634USA

We study continuous data assimilation(CDA)applied to projection and penalty methods for the Navier-Stokes(NS)*** and projection methods are more efficient than consistent Ns discretizations,however are less accurate due to modeling error(penalty)and splitting error(projection).We show analytically and numerically that with measurement data and properly chosen parameters,CDA can effectively remove these splitting and modeling errors and provide long time optimally accurate solutions.

关键词： Navier-Stokes equations projection method penalty method continuous data assimilation

Crystalline cyclic(alkyl)(amino)stannylene via transient stannyne

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Science China Chemistry 2024年

作者： Xinfeng Wang Chaopeng Hu Zhihao Lu Liu leo Liu Department of Chemistry and Research Center for Chemical Biology and Omics Analysis College of Science Southern University of Science and Technology

We demonstrate that a bulky cyclic amino ligand, specifically 1,1,3,3-tetraphenylisoindolinyl, can facilitate the formation of a transient stannyne, endowed with adjacent ambiphilic carbon and tin centers. This stannyne, manifesting carbene-like behavior,engages in an unprecedented sequence of reactions, including Buchner ring expansion, [1,3]sigmatropic, and [1,5]-sigmatropic shifts, culminating in the synthesis of a stable cyclic(alkyl)(amino)stannylene. This compound represents the first tin analogue of the well-known cyclic(alkyl)(amino)carbenes. Both the bonding configuration and the formation process of this stannylene are thoroughly analyzed through quantum chemical computations. Our findings pave the way for further synthesis of unusual main group species using bulky isoindolinyl substituents, emphasizing their potential as a versatile tool in synthetic chemistry.

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APIR:Aggregating Universal Proteomics Database Search Algorithms for Peptide Identification with FDR Control

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Genomics, Proteomics & Bioinformatics 2024年第2期22卷 171-187页

作者： Yiling Elaine Chen Xinzhou Ge Kyla Woyshner MeiLu McDermott Antigoni Manousopoulou Scott B.Ficarro Jarrod A.Marto Kexin Li leo David Wang Jingyi Jessica Li Department of Statistics and Data Science University of CaliforniaLos AngelesCA 90095USA Department of Immuno-Oncology Beckman Research InstituteCity of Hope National Medical CenterDuarteCA 91010USA Department of Quantitative and Computational Biology University of Southern CaliforniaLos AngelesCA 90089USA Department of Cancer Biology and Blais Proteomics Center Dana-Farber Cancer InstituteDepartment of PathologyBrigham and Women’s Hospital and Harvard Medical SchoolBostonMA 02215USA Department of Pediatrics City of Hope National Medical CenterDuarteCA 91010USA Bioinformatics Interdepartmental Program University of CaliforniaLos AngelesCA 90095USA Department of Human Genetics University of CaliforniaLos AngelesCA 90095USA Department of Computational Medicine University of CaliforniaLos AngelesCA 90095USA Department of Biostatistics University of CaliforniaLos AngelesCA 90095USA

Advances in mass spectrometry(MS)have enabled high-throughput analysis of proteomes in biological *** state-of-the-art MS data analysis relies on database search algorithms to quantify proteins by identifying peptide–spectrum matches(PSMs),which convert mass spectra to peptide *** database search algorithms use distinct search strategies and thus may identify unique ***,no existing approaches can aggregate all user-specified database search algorithms with a guaranteed increase in the number of identified peptides and a control on the false discovery rate(FDR).To fill in this gap,we proposed a statistical framework,Aggregation of Peptide Identification Results(APIR),that is universally compatible with all database search ***,under an FDR threshold,APIR is guaranteed to identify at least as many,if not more,peptides as individual database search algorithms *** of APIR on a complex proteomics standard dataset showed that APIR outpowers individual database search algorithms and empirically controls the *** data studies showed that APIR can identify disease-related proteins and post-translational modifications missed by some individual database search *** APIR framework is easily extendable to aggregating discoveries made by multiple algorithms in other high-throughput biomedical data analysis,e.g.,differential gene expression analysis on RNA sequencing *** APIR R package is available at https://***/yiling0210/APIR.

关键词： Shotgun proteomics Peptide–spectrum match Peptide identification Aggregation of lists FDR control

女性科研工作者的退出风险与学术成就学术界性别不平等之因

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科学大观园 2024年第6期 30-33页

作者： leo

学术界性别不平等的现象始终存在，也有不少研究对此表示关注，但由于各种原因没能够得出令人满意的结论。黄俊铭博士及其合作者，整合并运用前所未有的大规模数据库，进行了一项题为《不同国家和学科的科学职业中性别不平等的历史比较...

学术界性别不平等的现象始终存在，也有不少研究对此表示关注，但由于各种原因没能够得出令人满意的结论。黄俊铭博士及其合作者，整合并运用前所未有的大规模数据库，进行了一项题为《不同国家和学科的科学职业中性别不平等的历史比较》的研究。本文是对研究报告的详细解析，将从职业生涯、学术能力等不同角度透析学术界性别不平等之因。

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来源：博看期刊

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谁是歹人

作文 2024年第13期 2-2,1页

作者： leo

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