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Predicting Purchasing Behavior on E-Commerce Platforms: A Regression Model Approach for Understanding User Features that Lead to Purchasing

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International Journal of Communications, Network and System Sciences 2024年第6期17卷 81-103页

作者： Abraham Jallah Balyemah Sonkarlay J. Y. Weamie Jiang Bin Karmue vasco Jarnda Felix Jwakdak Joshua College of Computer Science and Engineering Hunan University Changsha China Department of Health Inspection and Quarantine Xiangya School of Public Health Central South University Changsha China

This research introduces a novel approach to improve and optimize the predictive capacity of consumer purchase behaviors on e-commerce platforms. This study presented an introduction to the fundamental concepts of the logistic regression algorithm. In addition, it analyzed user data obtained from an e-commerce platform. The original data were preprocessed, and a consumer purchase prediction model was developed for the e-commerce platform using the logistic regression method. The comparison study used the classic random forest approach, further enhanced by including the K-fold cross-validation method. Evaluation of the accuracy of the model’s classification was conducted using performance indicators that included the accuracy rate, the precision rate, the recall rate, and the F1 score. A visual examination determined the significance of the findings. The findings suggest that employing the logistic regression algorithm to forecast customer purchase behaviors on e-commerce platforms can improve the efficacy of the approach and yield more accurate predictions. This study serves as a valuable resource for improving the precision of forecasting customers’ purchase behaviors on e-commerce platforms. It has significant practical implications for optimizing the operational efficiency of e-commerce platforms.

关键词： E-Commerce Platform Purchasing Behavior Prediction Logistic Regression Algorithm

Simultaneous Neurocysticercosis and Cerebral Toxoplasmosis in a Patient Living with HIV—Case Report

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Generalized Krein Parameters of a Strongly Regular Graph

Advances in Infectious Diseases（传染病进展） 2023年第3期

作者： Ema Leal João Caria vasco almeida Claudina Cruz Ana Raquel Garrote Manuela Mafra Freddy Ramirez Diana Póvoas Maria José Manata Fernando Maltez

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Applied Mathematics 2015年第1期6卷 37-45页

作者： Luis almeida Vieira vasco Moco Mano CMUP—Center of Research of Mathematics of University of Porto Department of Civil EngineeringUniversity of PortoPortoPortugal CIDMA—Center for Research and Development in Mathematics and Applications Department of MathematicsUniversity of AveiroAveiroPortugal

We consider the real three-dimensional Euclidean Jordan algebra associated to a strongly regular graph. Then, the Krein parameters of a strongly regular graph are generalized and some generalized Krein admissibility conditions are deduced. Furthermore, we establish some relations between the classical Krein parameters and the generalized Krein parameters.

关键词： Algebraic Combinatorics Association Schemes Strongly Regular Graphs Graphs and Linear Algebra

Proportionally Modular Diophantine Inequalities and Their Multiplicity

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Acta Mathematica Sinica,English Series 2010年第11期26卷 2059-2070页

作者： José Carlos ROSALES Manuel Batista BRANCO Paulo vasco Departamento de lgebra Universidad de Granada Departamento de Matemática Departamento de Matemática Universidade de Trás-os-Montes e Alto Douro

Let I be an interval of positive rational numbers. Then the set S （I） = T ∩ N, where T is the submonoid of （Q0＋, ＋） generated by T, is a numerical semigroup. These numerical semigroups are called proportionally modular and can be characterized as the set of integer solutions of a Diophantine inequality of the form ax rood b 〈 cx. In this paper we are interested in the study of the maximal intervals I subject to the condition that S （I） has a given multiplicity. We also characterize the numerical semigroups associated with these maximal intervals.

关键词： Numerical semigroup Diophantine inequality multiplicity Frobenius number

Lensless diffractive imaging with ultra-broadbandtable-top sources: from infrared to extreme-ultravioletwavelengths

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Light(Science & Applications) 2014年第1期3卷 274-281页

作者： Stefan Witte vasco T Tenner Daniel WE Noom Kjeld SE Eikema LaserLaB Amsterdam VU University Amsterdam1081 HV AmsterdamThe Netherlands Present address:Huygens-Kamerlingh Onnes Laboratorium Universiteit Leiden2333 CA LeidenThe Netherlands

Lensless imaging is an approach to microscopy in which a high-resolution image of an object is reconstructed from one or more measured diffraction patterns,providing a solution in situations where the use of imaging optics is not ***,current lensless imaging methods are typically limited by the need for a light source with a narrow,stable and accurately known *** have developed a general approach to lensless imaging without spectral bandwidth limitations or sample *** use two time-delayed coherent light pulses and show that scanning the pulse-to-pulse time delay allows the reconstruction of diffraction-limited images for all the spectral components in the *** addition,we introduce an iterative phase retrieval algorithm that uses these spectrally resolved Fresnel diffraction patterns to obtain high-resolution images of complex extended *** demonstrate this two-pulse imaging method with octave-spanning visible light sources,in both transmission and reflection geometries,and with broadband extreme-ultraviolet radiation from a high-harmonic generation *** approach enables effective use of low-flux ultra-broadband sources,such as table-top high-harmonic generation systems,for high-resolution imaging.

关键词： coherent diffractive imaging extreme ultraviolet Fourier transform spectroscopy high-harmonic generation lensless imaging

Influence of Concentration of Vanadium in Zinc Oxide on Structural and Optical Properties with Lower Concentration

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Chinese Physics Letters 2009年第7期26卷 308-311页

作者：王丽伟徐征孟立建 vasco Teixeira 宋世庚徐叙瑢 Institute of Optoelectronics Technology and Key Laboratory of Luminescence and Optical Information Beijing Jiaotong University Beijing 100044 Departamento de Ffsica Instituto Superior de Engenharia do Porto Rua Dr. Antdnio Bernardino de Almeida 431 4200-072 Porto Portugal Centro de Ffsica Universidade do Minho Campus de Azurem 4800-058 Guimaraes Portugal 4Thin Film Center University of Paisley Paisley PAl 2BE Scotland Thin Film Oenter University of Paisley Paisley PAl 2BE Scotland

ZnO films doped with different vanadium concentrations are deposited onto glass substrates by dc reactive magnetron sputtering using a zinc target doped with vanadium. The vanadium concentrations are examined by energy dispersive spectroscopy （EDS） and the charge state of vanadium in ZnO thin films is characterized by x-ray photoelectron spectroscopy. The results of x-ray diffraction （XRD） show that all the films have a wurtzite structure and grow mainly in the c-axis orientation. The grain size and residual stress in the deposited films are estimated by fitting the XRD results. The optical properties of the films are studied by measuring the transmittance. The optical constants （refractive index and extinction coefficient） and the film thickness are obtained by fitting the transmittance. All the results are discussed in relation with the doping of the vanadium.

关键词： sea surface nonliear interaction numerical method

Compromised nutritional status in patients with end-stage liver disease:Role of gut microbiota

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Hepatobiliary & Pancreatic Diseases International 2018年第4期17卷 290-300页

作者： Maria vasco Rossella Paolillo Concetta Schiano Linda Sommese Oreste Cuomo Claudio Napoli U.O.C.Division of Clinical Immunology ImmunohematologyTransfusion Medicine and Transplant ImmunologyRegional Reference Laboratory of Transplant ImmunologyDepartment of Internal and Specialty MedicineAzienda Ospedaliera UniversitariaUniversitàdegli Studi della Campania“Luigi Vanvitelli”Naples 80138Italy IRCCS SDN NaplesItaly Department of Experimental Medicine Universitàdegli Studi della Campania“Luigi Vanvitelli”Naples 80138Italy Department of Liver Transplant AORN A.CardarelliNaplesItaly Department of Medical SurgicalNeurologicalMetabolic and Geriatric SciencesUniversitàdegli Studi della Campania“Luigi Vanvitelli”NaplesItaly

Background: Patients with end-stage liver disease(ESLD) have a compromised nutritional status because of the liver crucial role in regulating metabolic homeostasis and energy *** sources: A systematic review of literature based on extensive relevant articles published from 2001 to 2017 in English in Pub Med database was performed by searching keywords such as liver disease, nonalcoholic liver disease, alcoholic liver disease, malnutrition, epigenetics, gut microbiota, and ***: Liver transplantation would be one eligible therapy for ESLD patients, even if, the clinical outcome is negatively influenced by malnutrition and/or infections. The malnutrition is a condition of nutrient imbalance with a high incidence in ESLD patients. An accurate evaluation of nutritional status could be fundamental for reducing complications and prolonging the survival of ESLD patients including those undergoing liver transplantation. In addition, the interaction among nutrients, diet and genes via epigenetics has emerged as a potential target to reduce the morbidity and mortality in ESLD patients. The malnutrition induces changes in gut microbiota causing dysbiosis with a probable translocation of bacteria and/or pathogen-derived factors from the intestine to the liver. Gut microbiota contribute to the progression of chronic liver diseases as well as hepatocellular carcinoma. The administration of probiotics modulating gut microbiota could improve all chronic liver ***: This review provides an update on malnutrition status linked to epigenetics and the potential benefit of some probiotics on the management of ESLD patients. In support of this view and to reveal the constant and growing interest in this field, some clinical trials are reported.

关键词： Liver diseases Liver transplantation Epigenetics Malnutrition Probiotics

Mercury in sediments and vegetation in a moderately contaminated salt marsh (Tagus Estuary, Portugal)

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Journal of Environmental Sciences 2010年第8期22卷 1151-1157页

作者： Joao Canário Carlos Vale Laurier Poissant Marta Nogueira Martin Pilote vasco Branco INRB I.P./IPIMAR Av. Brasília Environment Canada Science and Technology Branch

Depth variations of total mercury （Hg） and methylmercury （MeHg） concentrations were studied in cores from non-colonized sediments, sediments colonized by Halimione portulacoides, Sarcocornia fruticosa and Spartina maritima and belowground biomass, in a moderately contaminated salt marsh （Tagus Estuary, Portugal）. Concentrations in belowground biomass exceeded up to 3 （Hg） and 15 （MeHg） times the levels in sediments, and up to 198 （Hg） and 308 （MeHg） times those found in aboveground parts. Methylmercury in colonized sediments reached 3% of the total Hg, 50 times above the maximum values found in non-colonized sediments. The absence of correlations between total Hg concentrations in sediments and the corresponding MeHg levels suggested that methylation was only dependent on the environmental and microbiological factors. The analysis of belowground biomass at high-depth resolution （2 cm） provided evidence that Hg and MeHg were actively absorbed from sediments, with higher enrichment factors at layers where higher microbial activity was probably occurring. The results obtained in this study indicated that the biotransformation of Hg to the toxic MeHg could increase the toxicity of plant-colonized sediments.

关键词： mercury methylmercury salt marshes Tagus Estuary Portugal

Phosphoinositide pathway and the signal transduction network in neural development

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Neuroscience Bulletin 2012年第6期28卷 789-800页

作者： Vincenza Rita Lo vasco Department Organi di Senso Policlinico Umberto IFaculty of MedicineSapienza University of Romeviale del Policlinico 33Rome 00185Italy

The development of the nervous system is under the strict control of a number of signal transduction pathways, often interconnected. Among them, the phosphoinositide （PI） pathway and the related phospholipase C （PI-PLC） family of enzymes have been attracting much attention. Besides their well-known role in the regulation of intracellular calcium levels, PI-PLC enzymes interact with a number of molecules belonging to further signal transduction pathways, contributing to a specific and complex network in the developing nervous system. In this review, the connections of PI signalling with further transduction pathways acting during neural development are discussed, with special regard to the role of the PI-PLC family of enzymes.

关键词： phospholipase C CNS development calcium release