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Integral Representation Formulas Related to the Lamé–Navier System

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Acta Mathematica Sinica,English Series 2020年第12期36卷 1341-1356页

作者： Ricardo ABREU-BLAYA juan BORY-REYES Marcos antonio-HERRERA-PELáEZ José María SIGARRETA-ALMIRA Facultad de Matemáticas Universidad Autónoma de GuerreroGuerreroMéxico Instituto Politécnico Nacional SEPI-ESIME-ZAC CD-MXMéxico

The paper provides integral representations for solutions to a certain first order partial differential equation natural arising in the factorization of the Lamé–Navier system with the help of Clifford analysis techniques.These representations look like in spirit to the Borel–Pompeiu and Cauchy integral formulas both in three and higher dimensional setting.

关键词： Lamésystem Clifford analysis Dirac operator

Effect of Organo-Modified Nanosepiolite on Fire Behaviors and Mechanical Performance of Polypropylene Composites

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中国化学:英文版 2015年第2期33卷 285-291页

作者： Junhao Zhang Sergio de juan antonio Esteban-Cubillo Julio Santarén De-Yi Wang Madrid Institute for Advanced Studies of Materials(IMDEA-Materials) C/Eric Kandel2Getafe(Madrid)28906Spain Tolsa S.A.R.&D.Department Carretera de Madrid a Rivas Jarama3528031 MadridSpain

The objective of the study was to investigate the effect of the organo-modified nanosepiolite(ONSep)on improving the fire safety of polypropylene(PP).The composites based on PP,flame retardant master batch(MB-FR,25 wt%PP+50 wt%decabromodiphenyl ether(DBDPE)+25%antimony trioxide(ATO))and ONSep were prepared via melt blending.The results of the limiting oxygen index(LOI)and vertical burning rating(UL-94)test indicated that PP/40 wt%MB composites had no rating with seriously dripping phenomenon,while the LOI value was only 22.5.However,as 4 wt%ONSep was added in PP/40 wt%MB composites,the composites achieved UL94 V-0 rating and the LOI value was 24.3.In comparison,PP/50 wt%MB composites could not reach the V-0 rating either.The TGA results revealed that the addition of ONSep enhanced the thermal stability of the PP/MB-FR composites.The cone calorimeter results indicated that the heat release rate,average mass loss rate,smoke production rate and smoke temperature of the PP/40 wt%MB-FR/4 wt%ONSep composites decreased in comparison with those of PP/40 wt%MB-FR composites.Simultaneously,the Young modulus and impact strength were also much better improved with the increase of ONSep loading.Therefore,the synergistic flame retardancy of ONSep in PP/MB-FR matrix significantly containing a halogen based flame retardant(DBDPE)significantly improved the fire safety and mechanical properties of the composites,and allowed to decrease the total amount of brominated fire retardants.

关键词： nanosepiolite polypropylene flame retardancy heat release rate

Event-triggered leader-following formation control for multi-agent systems under communication faults: application to a fleet of unmanned aerial vehicles

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Journal of Systems Engineering and Electronics 2021年第5期32卷 1014-1022页

作者： VAZQUEZ TREJO juan antonio GUENARD Adrien ADAM-MEDINA Manuel PONSART Jean-Christophe CIARLETTA Laurent ROTONDO Damiano THEILLIOL Didier Research Center for Automatic Control of Nancy University of LorraineNancy F-54000France Electronic Engineering Department National Institute of Technology of MexicoCuernavaca Morelos 62490Mexico Lorraine Research Laboratory in Computer Science and Its Applications University of LorraineNancy F-54000France University of Stavanger Department of Electrical and Computer EngineeringStavanger 4021Norway

The main contribution of this paper is the design of an event-triggered formation control for leader-following consensus in second-order multi-agent systems(MASs)under communication faults.All the agents must follow the trajectories of a virtual leader despite communication faults considered as smooth time-varying delays dependent on the distance between the agents.Linear matrix inequalities(LMIs)-based conditions are obtained to synthesize a controller gain that guarantees stability of the synchronization error.Based on the closed-loop system,an event-triggered mechanism is designed to reduce the control law update and information exchange in order to reduce energy consumption.The proposed approach is implemented in a real platform of a fleet of unmanned aerial vehicles(UAVs)under communication faults.A comparison between a state-of-the-art technique and the proposed technique has been provided,demonstrating the performance improvement brought by the proposed approach.

关键词： event-triggered leader-following consensus communication fault formation control unmanned aerial vehicle(UAV) experimental result

Cigarette smoking, dietary habits and genetic polymorphisms in GSTT1, GSTM1 and CYP1A1 metabolic genes: A case-control study in oncohematological diseases

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世界临床肿瘤学杂志：英文版 2016年第5期7卷 395-405页

作者： María Belén Cerliani Walter Pavicic juan antonio Gili Graciela Klein Silvia Saba Silvina Richard Instituto Multidisciplinario de Biología Celular (CIC UNLP CONICET) Laboratorio de Epidemiología Genética (ECLAMC CEMIC CONICET CABA) Unidad de Diagnóstico Tratamiento y Sostén de Enfermedades Hematológicas Hospital Interzonal General de Agudos Prof. Dr. Rodolfo Rossi

AIM To analyze the association between oncohematological diseases and GSTT1 /GSTM1 /CYP1A1 polymorphisms, dietary habits and smoking, in an argentine hospitalbased case-control study.METHODS This hospital-based case-control study involved 125 patients with oncohematological diseases and 310 control subjects. A questionnaire was used to obtain sociodemographic data and information about habits. Blood samples were collected, and DNA was extracted using salting out methods. Deletions in GSTT1 and GSTM1 (null genotypes) were addressed by PCR. CYP1A1 MspI polymorphism was detected by PCR-RFLP. Odds ratio(OR) and 95%CI were calculated to estimate the association between each variable studied and oncohematological disease.RESULTS Women showed lower risk of disease compared to men(OR 0.52, 95%CI: 0.34-0.82, P = 0.003). Higher levels of education(> 12 years) were significantly associated with an increased risk, compared to complete primary school or less(OR 3.68, 95%CI: 1.82-7.40, P < 0.001 adjusted for age and sex). With respect to tobacco, none of the smoking categories showed association with oncohematological diseases. Regarding dietary habits, consumption of grilled/barbecued meat 3 or more times per month showed significant association with an increased risk of disease(OR 1.72, 95%CI: 1.08-2.75, P = 0.02). Daily consumption of coffee also was associated with an increased risk(OR 1.77, 95%CI: 1.03-3.03, P = 0.03). Results for GSTT1, GSTM1 and CYP1A1 polymorphisms showed no significant association with oncohematological diseases. When analyzing the interaction between polymorphisms and tobacco smoking or dietary habits, no statistically significant associations that modify disease risk were found. CONCLUSION We reported an increased risk of oncohematological diseases associated with meat and coffee intake. We did not find significant associations between genetic polymorphisms and blood cancer.

关键词： Cancer Oncohematological disease Casecontrol study Lifestyle Diet Tobacco Xenobiotic metabolizing genes GSTT1 GSTM1 CYP1A1

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地震光和地震地面加速度之间的时间差相关性

Applied Geophysics 2021年第1期18卷 9-16,128页

作者： juan antonio Lira Maurizio Mulas Facultad de Ciencias Físicas Universidad Nacional Mayor de San MarcosLima 1Peru Sección Física Departamento Académico de CienciasPontificia Universidad Católica del PerúLima 32Peru Escuela Superior Politécnica del Litoral ESPOLFacultad de Ingeniería en Ciencias de la TierraCampus Gustavo Galindo Km 30.5 Vía PerimetralP.O.Box 09-01-5863

虽然自古以来就知道地震光,但直到60年代,才拍摄下第一张地震光照片。在2007年在秘鲁发生地震期间,录下了第一部地震光录像。同样,在2016年瓜多尔地震和2017年墨西哥地震期间,记录了两部地震光电影。这些电影记录,无论是客观还是信息内... 详细信息

虽然自古以来就知道地震光,但直到60年代,才拍摄下第一张地震光照片。在2007年在秘鲁发生地震期间,录下了第一部地震光录像。同样,在2016年瓜多尔地震和2017年墨西哥地震期间,记录了两部地震光电影。这些电影记录,无论是客观还是信息内容,都有助于研究地震光。已经提出了几种解释地震光的因果机制:压电性、氡放射、流体扩散、摩擦汽化、正极洞穴和偶极电流等等。在这项工作中,我们发现了地震光和地震地面加速度之间的时间差相关性,并使用地震数据和地震光的胶片记录来解释其起源。在讨论部分,建议岩石破裂在某种程度上表现为通过感应产生静电的地震光。我们建立了一个新的感应模型,可以用于解释EQL的形成,即使地壳具有大电阻率层。该模型还解释了地震光的形成,而不需要地球表面或大气中的特殊条件。更好地理解地震光的生成过程可以提高我们对地震活动的理解,并有助于预测地震。

关键词：时差相关性地震光地震地面加速度岩石破裂

Performance of statistical and machine learning-based methods for predicting biogeographical patterns of fungal productivity in forest ecosystems

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Forest Ecosystems 2021年第2期8卷 278-291页

作者： Albert Morera juan Martínez de Aragón José antonio Bonet Jingjing Liang Sergio de-Miguel Department of Crop and Forest Sciences University of LleidaAv.Alcalde Rovira Roure 191E-25198 LleidaSpain Joint Research Unit CTFC-AGROTECNIO-CERCA Center Av.Rovira Roure 19125198 LleidaSpain Forest Science and Technology Centre of Catalonia Ctra.Sant Llorençde Morunys km 225280 SolsonaSpain Forest Advanced Computing and Artificial Intelligence Laboratory Department of Forestry and Natural ResourcesPurdue UniversityWest LafayetteIN 47907USA

Background:The prediction of biogeographical patterns from a large number of driving factors with complex interactions,correlations and non-linear dependences require advanced analytical methods and modeling tools.This study compares different statistical and machine learning-based models for predicting fungal productivity biogeographical patterns as a case study for the thorough assessment of the performance of alternative modeling approaches to provide accurate and ecologically-consistent predictions.Methods:We evaluated and compared the performance of two statistical modeling techniques,namely,generalized linear mixed models and geographically weighted regression,and four techniques based on different machine learning algorithms,namely,random forest,extreme gradient boosting,support vector machine and artificial neural network to predict fungal productivity.Model evaluation was conducted using a systematic methodology combining random,spatial and environmental blocking together with the assessment of the ecological consistency of spatially-explicit model predictions according to scientific knowledge.Results:Fungal productivity predictions were sensitive to the modeling approach and the number of predictors used.Moreover,the importance assigned to different predictors varied between machine learning modeling approaches.Decision tree-based models increased prediction accuracy by more than 10%compared to other machine learning approaches,and by more than 20%compared to statistical models,and resulted in higher ecological consistence of the predicted biogeographical patterns of fungal productivity.Conclusions:Decision tree-based models were the best approach for prediction both in sampling-like environments as well as in extrapolation beyond the spatial and climatic range of the modeling data.In this study,we show that proper variable selection is crucial to create robust models for extrapolation in biophysically differentiated areas.This allows for reducing the dimensions of the ecosystem space described by the p

关键词： Modeling Regression Biogeography Climate Forest Fungi Mushrooms

Interaction of piRNA-like sequences from the 3′-UTR of SARS-CoV-2 with mRNA regions

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Genes & Diseases 2023年第6期10卷 2282-2284页

作者： Laura Pérez-Campos Mayoral María Teresa Hernández-Huerta Carlos Romero Díaz Carlos Alberto Matias-Cervantes Eduardo Pérez-Campos Mayoral Margarito Martínez Cruz juan de Dios Ruiz-Rosado Edgar Gustavo Ramos Martínez Marco antonio Sánchez Medina Eduardo Pérez-Campos Research Center Faculty of Medicine UNAM-UABJOAutonomous University“Benito Juárez”of Oaxaca(UABJO)Oaxaca 68020Mexico CONACyT Faculty of Medicine and Surgery.Autonomous University“Benito Juárez”of Oaxaca(UABJO)Oaxaca 68020Mexico National Technology of Mexico(TecNM)/IT Oaxaca Oaxaca de JuárezOaxaca 68030Mexico The Research Institute at Nationwide Children's Hospital Columbus 43205USA Facultad de Química Universidad Nacional Autónoma de MéxicoCoyoacán 04510Mexico

Piwi-interacting RNAs(piRNAs of 26-32 nt in length)regulate gene expression,epigenetics,and transcriptional and post-transcriptional processes.1 In humans,piRNAs are expressed in germline and somatic tissues,and generally have a uracil at the 5'-end(position+1),an adenine at the+10 position,and are 2'-0 methylated at the 3'-end.2 Onice piRNAs form the RNA-induced silencing complex(RISC)with PIWl proteins,they serve as guides to find their complementary sequences of the target mRNA,thus initiating their degradation.The Wuhan patient's genome is approximately 265 nucleotides(nts)in its 3'-UTR;piRNAs-like sequences have been reported in this region.3 Our objective was to search,through bioinformatics,for mRNA sequences that were homologous to the reverse complementary of the previously reported piRNA-like sequences from the 3'-UTR of SARS-Cov-2,3 and identify the possible interaction between them.

关键词： sequences complementary initiating

Comparison of Apigenin,Quercetin and Kaempferol Accumulation and Total Flavonoid Content in Leaves,Embryogenic Cultures and Cell Suspension Cultures of Parsley(Petroselinum crispum)

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国际实验植物学杂志(英文) 2023年第10期92卷 2807-2823页

作者： Laura Isabel Arias-Rodríguez Martha Alicia Rodríguez-Mendiola Carlos Arias-Castro Federico antonio Gutiérrez Miceli Diana Reséndez Pérez María Celina Luján Hidalgo juan JoséVillalobos Maldonado Norma Alejandra Mancilla Margalli Analytical Laboratory National Technological Institute of MexicoTuxtla Gutierrez CampusTuxtla GutierrezMexico Plant Biotechnology Laboratory Instrumental Analysis LaboratoryPlant Biochemistry LaboratoryNational Technological Institute of MexicoTlajomulco de ZunigaMexico Department of Cellular Biology and Genetics Faculty of Biological SciencesAutonomous University of Nuevo LeonSan Nicolas delos GarzaMexico

In recent years,there has been a growing interest in exploring alternative treatments for bone defects.Bone tissue engineering has turned its attention to plant extracts containing osteogenic flavonoids as potential promoters of bone regeneration.In our study,we specifically investigated the extract of Petroselinum crispum,a plant known for its abundance of osteogenic flavonoids such as apigenin,quercetin,and kaempferol.Our objective was to compare the total flavonoid content(TFC)and their accumulation in different sources.We obtained hydrolyzed aqueous extracts from the leaves of parsley plants(grown for 12 weeks in the field),weekly embryogenic cultures,and suspension cell cultures.The TFC,measured in mg quercetin equivalent per gram of dry weight(QE mg/g dw),was found to be 53.81±0.97 for 52 g dw of leaves(1 kg plant fw),31.10±1.52 for 420 g dw of embryogenic cultures,and 11.80±0.76 for 210 g dw of cell suspensions.Notably,only the leaves and embryogenic cultures showed significant accumulation of osteogenic flavonoids,with apigenin levels of 1.8±0.3 and 0.32±0.02 mg/g dw,and kaempferol levels of 1.0±0.18 and 0.2±0.01 mg/g dw,respectively.Our findings indicate that embryogenic cultures have the potential to produce up to 40%more apigenin in 12 weeks compared to 1 kg of parsley plant,thanks to their superior biomass reproductive competence.These results present a promising biotechnological approach for generating extracts enriched with bioactive compounds,which can be further utilized in in vitro osteogenic testing.

关键词： Parsley(Petroselinum crispum)cultures osteogenic flavonoids bone regeneration aqueous extracts

Earth-Moon Barycentre Excursions and Anomalous Quaternary Sea Level Highstands

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International Journal of Geosciences 2022年第8期13卷 627-656页

作者： Joaquin Meco Consuelo Sendino Alejandro Lomoschitz antonio Núñez María José Huertas juan F. Betancort Departamento de Biología Facultad de Ciencias del Mar Universidad de Las Palmas de Gran Canaria (ULPGC) Las Palmas de Gran Canaria Spain Department of Earth Sciences Natural History Museum London United Kingdom Instituto de Oceanografía y Cambio Global IOCAG Universidad de Las Palmas de Gran Canaria ULPGC Las Palmas de Gran Canaria Spain Department of Electrical and Electronics Engineering Universidad de Las Palmas de Gran Canaria ULPGC Las Palmas de Gran Canaria Spain Departamento de Mineralogía y Petrología Facultad de Ciencias Geológicas Universidad Complutense de Madrid (UCM) Madrid Spain

Plate tectonics is driven by Earth-Moon barycentre shifts in the lower mantle. The eastern Canary Islands have geographic and geological conditions derived from the movements of the Central American plates. Some features of these islands are influenced by the rotation of the Earth from west to east in the evolution of the marine currents that surround them and the opening of the North Atlantic to the North Pole with little dependence of the glacial isostatic adjustment (GIA). In addition, their position with respect to the Tropic of Cancer and the African continent affect the north-south and east-west climatic change dynamics and their tectonic stability respectively. Dated lavas contain marine and aeolian deposits and some of the Pleistocene marine deposits indicate higher sea level in cooler circumstances, which is anomalous. Relating those marine deposits produced during the warmest interglacial, the last interglacial and the Holocene with their equivalents in the Southern Hemisphere, they reflect shifts in the barycentre. Thanks to Holocene radiocarbon, topographic and day length data and alkenone temperature, we describe a mechanism by which the oscillation of the Moon’s inclination (and declination) reaches extreme values (14ºand 34ºabout 4.9ºmore than current values) approximately every 1450 years. These values occur when there is a harmonic distortion in surface areas of the Earth’s crust as response associated with oscillations in the displacements of the barycentre of the Earth-Moon system. As the declination influences the movement of oceanic waters, there is also a relationship with the Bond Events of the North Atlantic, of unknown cause until now.

关键词： Earth-Moon Barycentre Lunar Declination Sea-Level Canary Islands Neogene Quaternary