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Acta Mathematica Sinica,English Series 2001年第4期17卷 581-594页

作者： Qi Qing YU Lin Xiong LI Mathematics department, SUNY at Binghamton, Binghamton, NY 13902, usa Mathematics department. Zhongshan university, Guangzhou 510275, P. R. China department of Mathematics. university of new orleans, new orleans, la 70148, usa Mathematics department SUNY at Binghamton Binghamton USA Mathematics department Zhongshan University Guangzhou 510275 P. R. China department of Mathematics University of New Orleans New Orleans USA

The asyrmptotic properties of the self-consistent estimator (SCE) of a distribution function F of a random variable X with doubly-censored data are examined by several authors under the asstumption that X is observable everywhere in the interval [a, b], where a=inf{x: F(x)>0} and b=sup{x: F(x)<1}. Such an assumption does not allow the situation that X is discrete and the situation that X is only observable in a nontrivial subinterval of [a, b]. However, often in practice this assumption is not satisfied. In this manuscript we establish strong uniform consistency, asymptotic normality and asymptotic efficiency of the SCE under a set of assumptions that allow the situation that X is discrete and the situation that X is only observable in a nontrivial subinterval of [a, b]. Finally, we point out a gap in the proofs of the existing results in the literature due to the definition of the SCE.

关键词： Asymptotic normality Generalized MLE Right censoring Self-consistent algorithm Strong consistency

The inhomogeneous incompressible Hall-MHD system with only bounded density

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Science China Mathematics 2024年

作者： jin tan lan Zhang laboratoire de Math′ematiques AGM UMR CNRS 8088 Cergy Paris Universit′e Center for Mathematical Sciences and department of Mathematics Wuhan University of Technology

This paper is dedicated to the global-in-time existence and uniqueness issues of solutions for the inhomogeneous incompressible Hall-magnetohydrodynamics(MHD) system with merely bounded density. In a three-dimensional case, assuming that the initial density is a small perturbation of a positive constant in the L∞norm, we prove global well-posedness for small initial velocity and magnetic fields in critical Besov spaces. Next, we consider the so-called 21/2D flows for the inhomogeneous Hall-MHD system(that is 3D flows independent of the vertical variable) and establish the global existence of strong solutions by only assuming that the initial magnetic field is small in critical spaces and the initial density is bounded and bounded away from zero. In particular, those solutions allow piecewise constant density with jumps so that a mixture of fluids can be considered. Compared with inhomogeneous incompressible Navier-Stokes equations, the new difficulties of proving these results come from the additional so-called Hall term, which endows the magnetic equation with a quasi-linear character. In order to overcome them, we reformulate the system by taking advantage of the curl form of the magnetic equation and develop some new maximal regularity estimates for the Stokes system with just bounded coefficients.

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Intelligent　Information　Management　and　Knowledge　Discovery　in　large　Numeric　and　Scientific　Databases

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Journal of Systems Engineering and Electronics 1996年第2期7卷 73-86页

作者： Patrick Perrin Frederick E. Petry & William Thomason(Center for Intelligent and Knowledge-Based Systems)(Computer Science department, Tulane university, new orleans la) Center for Intelligent and Knowledge-Based Systems Computer Science department Tulane University New Orleans LA

The present article outlines progress made in designing an intelligent information system for automatic management and knowledge discovery in large numeric and scientific databases, with a validating application to the CAST-NEONS environmental databases used for ocean modeling and prediction. We describe a discovery-learning process (Automatic Data Analysis System) which combines the features of two machine learning techniques to generate sets of production rules that efficiently describe the observational raw data contained in the database. Data clustering allows the system to classify the raw data into meaningful conceptual clusters, which the system learns by induction to build decision trees, from which are automatically deduced the production rules.

关键词： Knowledge discovery in databases Machine learning Decision tree inducers

CHIRAL CONJUGATED OLIGOMER BASED ON 1,1’-BINOL WITH 3,3’-ACETYLENE-PHENYLENE-ACETYLENE SPACER

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Chinese Journal of Polymer Science 2001年第5期19卷 521-526页

作者： Tian-jun Liu ke-shen Zhang Yong-jun Chen Dong Wang Chao-jun Li Center for Molecular Science, Institute of Chemistry Chinese Academy of Sciences, Beijing 100080 China department of Chemistry Tulane university new orleans, la 70118 U.S.A. 中科院化学所北京 Tulane university 美国

The 1,2'-binaphthol based oligomers 3 and 7 with 3,3'-acetylene-phenylene-acetylene spacer were prepared from BINOL 1. The high optical rotation value and CD spectra demonstrated the main chain chirality of the oligomer molecule. The UV-VIS and fluorescent spectra evidence the characteristics of conjugated structure. In comparison with oligomer 2 bearing 3,3'-acetylene spacer, the oligomers 3 and 7 have longer efficient conjugation segment, and their fluorescent quantum yields (phi) increased (0.60-0.65 versus 0.14). Extending the effective conjugation segment would improve the photophysical properties of chiral conjugated polymers.

关键词： chiral conjugated oligomer BINOL 3,3 '-acetylene-phenylene-acetylene spacer

Clinical observation of extraction-site incisional hernia after laparoscopic colorectal surgery

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World Journal of Gastrointestinal Surgery 2024年第3期16卷 710-716页

作者： Bao-Hang Fan ke-Li Zhong Li-jin Zhu Zhao Chen Fang Li Wen-Fei Wu Second Clinical Medical College of jinan university Jinan UniversityShenzhen 518020Guangdong ProvinceChina department of Gastrointestinal Surgery Shenzhen People’s Hospital(The Second Clinical Medical CollegeJinan UniversityThe First Affiliated HospitalSouthern University of Science and Technology)Shenzhen 518020Guangdong ProvinceChina department of Radiation Oncology Shenzhen People’s Hospital(The Second Clinical Medical CollegeJinan UniversityThe First Affiliated HospitalSouthern University of Science and Technology)Shenzhen 518020Guangdong ProvinceChina

BACKGROUND laparoscopic colorectal cancer surgery increases the risk of incisional hernia(IH)at the tumor extraction *** To investigate the incidence of IH at extraction sites following laparoscopic colo-rectal cancer surgery and identify the risk factors for IH *** This study retrospectively analyzed the data of 1614 patients who underwent la-paroscopic radical colorectal cancer surgery with tumor extraction through the abdominal wall at our center between January 2017 and December ***-rences in the incidence of postoperative IH at different extraction sites and the risk factors for IH incidence were *** Among the 1614 patients who underwent laparoscopic radical colorectal cancer surgery,303(18.8%),923(57.2%),171(10.6%),and 217(13.4%)tumors were ex-tracted through supraumbilical midline,infraumbilical midline,umbilical,and off-midline *** these,52 patients developed IH in the abdominal wall,with an incidence of 3.2%.The incidence of postoperative IH was significantly higher in the off-midline incision group(8.8%)than in the middle incision groups[the supraumbilical midline(2.6%),infraumbilical midline(2.2%),and umbilical incision(2.9%)groups](χ^(2)=24.985;Plarly,multivariate analysis showed that off-midline incision,age,sex(female),obesity,incision infection,combined chronic cough,and hypoproteinemia were independent risk factors for IH at the site of laparoscopic colorectal cancer surgery(Plaparoscopic colorectal cancer *** infraumbilical midline incision is associated with a lower hernia rate and is thus a suitable tumor extraction site.

关键词： Incisional hernia laparoscopy Colorectal cancer Incision infection

Stereotactic body radiotherapy in pancreatic adenocarcinoma

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Hepatobiliary & Pancreatic Diseases International 2024年第1期23卷 14-19页

作者： Carolina de la Pinta Radiation Oncology department Ramón y Cajal University HospitalIRYCISAlcaláUniversity28034 MadridSpain

Background:Stereotactic body radiotherapy(SBRT)in pancreatic cancer allows high delivery of radiation doses on tumors without affecting surrounding *** review aimed at the SBRT application in the treatment of pancreatic *** sources:We retrieved articles published in MEDLINE/PubMed from January 2017 to December *** used in the search included:“pancreatic adenocarcinoma”OR“pancreatic cancer”AND“stereotactic ablative radiotherapy(SABR)”OR“stereotactic body radiotherapy(SBRT)”OR“chemoradiotherapy(CRT)”.English language articles with information on technical characteristics,doses and fractionation,indications,recurrence patterns,local control and toxicities of SBRT in pancreatic tumors were *** articles were assessed for validity and relevant ***:Optimal doses and fractionation have not yet been ***,SBRT could be the standard treatment in patients with pancreatic adenocarcinoma in addition to ***,the combination of SBRT with chemotherapy may have additive or synergic effect on pancreatic ***:SBRT is an effective modality for patients with pancreatic cancer,supported by clinical practice guidelines as it has demonstrated good tolerance and good disease *** opens a possibility of improving outcomes for these patients,both in neoadjuvant treatment and with radical intent.

关键词： Chemoradiotherapy Pancreatic adenocarcinoma Radiotherapy Stereotactic body radiotherapy Stereotactic ablative radiotherapy

Msx homeobox gene family and craniofacial development

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Cell Research 2003年第6期13卷 429-442页

作者： SYLVIA AlaPPAT Division of Developmental Biology department of Cell and Molecular Biology Tulane university new orleans la 70118 usa.

Vertebrate Msx genes are unlinked, homeobox-containing genes that bear homology to the Drosophila muscle segment homeobox gene. These genes are expressed at multiple sites of tissue-tissue interactions during vertebrate embryonic development. Inductive interactions mediated by the Msx genes are essential for normal craniofacial, limb and ectodermal organ morphogenesis, and are also essential to survival in mice, as manifested by the pheno typic abnormalities shown in knockout mice and in humans. This review summarizes studies on the expression, regulation, and functional analysis of Msx genes that bear relevance to craniofacial development in humans and mice.

关键词： Msx genes craniofacial tooth cleft palate suture development transcription factor signaling molecule.

A convolutional neural network to detect possible hidden data in spatial domain images

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Cybersecurity 2024年第1期7卷 37-52页

作者： Jean De la Croix Ntivuguruzwa Tohari Ahmad department of Informatics Institut Teknologi Sepuluh Nopember(ITS)Kampus ITS Keputih SukoliloSurabaya60111Indonesia African Center of Excellence in the Internet of Things College of Science and TechnologyUniversity of Rwanda3900KigaliRwanda

Hiding secret data in digital multimedia has been essential to protect the ***,attackers with a steganalysis technique may break *** steganalysis methods have good results with conventional Machine Learning(ML)techniques;however,the introduction of Convolutional Neural Network(CNN),a deep learning paradigm,achieved better performance over the previously proposed ML-based *** the existing CNN-based approaches yield good results,they present performance issues in classification accuracy and stability in the network training *** research proposes a new method with a CNN architecture to improve the hidden data detection accuracy and the training phase stability in spatial domain *** proposed method comprises three phases:pre-processing,feature extraction,and ***,in the pre-processing phase,we use spatial rich model filters to enhance the noise within images altered by data hiding;secondly,in the feature extraction phase,we use two-dimensional depthwise separable convolutions to improve the signal-to-noise and regular convolutions to model local features;and finally,in the classification,we use multi-scale average pooling for local features aggregation and representability enhancement regardless of the input size variation,followed by three fully connected layers to form the final feature maps that we transform into class probabilities using the softmax *** results identify an improvement in the accuracy of the considered recent scheme ranging between 4.6 and 10.2%with reduced training time up to 30.81%.

关键词： Information security Spatial domain steganalysis Deep learning Convolutional neural network Infrastructure

Lithium Isotope Analytical Methods and Implications for Rare-Metal Mineralization in Granite-Pegmatite Systems: An Overview

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Journal of Earth Science 2024年

作者： Xiang-Ying Ye Bin Li Dong-Bo tan ke-Cheng Liu Zhi-Yong Zhu Hafiz Muhammad Siddique Yi-Lin Xiao key laboratory of Metallogenic Prediction of Nonferrous Metals and Geological Environment Monitoring (Ministry of Education)， School of Geosciences and Info-physics， Central South university CAS key laboratory of Geospace Environment and department of Plasma physics and Fusion Engineering， university of Science and Technology of China Institute of Geology， Chinese Academy of Geological Sciences CAS key laboratory of Crust-Mantle Materials and Environments， School of Earth and Space Sciences， university of Science and Technology of China Chinese Academy of Sciences Center of Excellence in Comparative Planetology

The origin of highly-fractionated granite-pegmatite systems and their associated rare metal mineralization has been widely studied， but there is still ongoing debate. Prevailing hypotheses suggest that pegmatite formation and the associated rare metal mineralization are closely related to aqueous fluid processes. Lithium (Li) isotope analysis has been widely applied to trace granite-pegmatite evolution. This is because lithium is widely present in various minerals (e.g.， mica， tourmaline) that record the melt and fluid compositions， and lithium isotopes are sensitive to magmatic-hydrothermal processes. We briefly review the methodology of Li isotope analyses， the mechanisms of Li isotopic fractionation， and， in particular， Li isotope fractionation in granite-pegmatite system based on Li isotope data we have collected and the latest developments in Li isotope geochemistry. With the development of analytical technology， high-precision measurement of the Li content and isotopic compositions have facilitated a series of scientific breakthroughs in understanding the magmatic-hydrothermal evolution of rare-element ore deposits. Li isotope analysis on bulk mineral separates show ability to trace various hydrothermal processes (e.g. exotic or exsolved fluids). In situ Li isotope analysis methods has been enhanced by the development of new， homogeneous mineral reference materials. In situ SIMS and la-MC-ICP-MS Li isotope measurements on minerals (e.g.， tourmaline) will likely become more important in studying the fluid–rock interactions in magmatic， metamorphic， and hydrothermal processes， as well as on pegmatite petrogenesis and rare-metal mineralization.

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