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Biogeographic diversification in nolana(Solanaceae),a ubiquitous member of the Atacama and Peruvian deserts along the western coast of South America

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Journal of Systematics and Evolution 2009年第5期47卷 457-476页

作者： Michael O.DILLOn Victor QUIPUSCOA SILVESTRE department of Botany The Field Museum1400 South Lake Shore DriveChicagoIL 60605USA departamento de Botánica Universidad Nacional de San Agustín

The present paper reconstructs the biogeographic diversification for nolana L.f.(Solanaceae),a genus of 89 endemic species largely restricted to fog-dependent desert lomas formations of coastal Peru and *** efforts have reconstructed a phylogenetic estimate for nolana using a combination of molecular ***,we expand on those results to examine hypotheses of biogeographic origins and diversification *** occupies habitats within a continuous coastal desert and forms a terrestrial archipelago of discrete "islands" unique in size,topography,and species *** locality contains at least one nolana species and many contain multiple species in *** genus has a Chilean origin,with the basal clades confined to Chile with wide geographic and ecological *** contains two strongly supported clades,suggesting two introductions with subsequent radiation.A Chilean clade of shrubby,small-flowered species appears to have had its origins from the same ancestors of the second line that radiated in Peru and northern *** galapagensis is endemic to the Islas Gala’pagos,with origins traced to Peruvian taxa with a divergence time of 0.35 *** of diversification over the past 4.02 mya in nolana,in one of the driest habitats on Earth,suggest rapid adaptive radiation in several *** in nolana may be attributed to characters that confer a competitive advantage in unpredictable and water-dependent environments,such as succulent leaf anatomy and ecophysiology,and the reproductive mericarp unique to *** processes affecting or shaping the biota of western South America are discussed.

关键词： Atacama desert biogeography chloroplast DnA LEAFY second intron nolana Peruvian desert Solanaceae South America.

Human Interaction Dynamics for Its Use in Mobile Robotics:Impedance Control for Leader-follower Formation

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IEEE/CAA Journal of Automatica Sinica 2017年第4期4卷 696-703页

作者： Daniel Herrera Flavio Roberti Marcos Toibero Ricardo Carelli Instituto de Automatica universidad nacional de san Juan-COnICET IEEE

A complete characterization of the behavior in human-robot interactions(HRI) includes both: the behavioral dynamics and the control laws that characterize how the behavior is regulated with the perception data. In this way, this work proposes a leader-follower coordinate control based on an impedance control that allows to establish a dynamic relation between social forces and motion error. For this, a scheme is presented to identify the impedance based on fictitious social forces, which are described by distance-based potential *** part of the validation procedure, we present an experimental comparison to select the better of two different fictitious force structures. The criteria are determined by two qualities: least impedance errors during the validation procedure and least parameter variance during the recursive estimation ***, with the best fictitious force and its identified impedance,an impedance control is designed for a mobile robot Pioneer 3AT,which is programmed to follow a human in a structured *** to results, and under the hypothesis that moving like humans will be acceptable by humans, it is believed that the proposed control improves the social acceptance of the robot for this kind of interaction.

关键词： Human modeling human-machine interaction impedance control robot dynamics social robotics

Inequalities for the Extended Best Polynomial Approximation Operator in Orlicz Spaces

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Acta Mathematica Sinica,English Series 2019年第2期35卷 185-203页

作者： Sonia ACInAS Sergio FAVIER Felipe ZO departamento de Matemática Facultad de Ciencias y Exactas NaturalesUniversidad Nacional de La Pampa Instituto de Matemática Aplicada san Luis IMASLUniversidad Nacional de San Luis and CONICET departamento de Matemática Universidad Nacional de San Luis

In this paper we pursue the study of the best approximation operator extended from L~Φ to L~φ, where φ denotes the derivative of the function Φ. We get pointwise convergence for the coefficients of the extended best approximation polynomials for a wide class of function f, closely related to the Calder′on–Zygmund class t_m^p(x) which had been introduced in 1961. We also obtain weak and strong type inequalities for a maximal operator related to the extended best polynomial approximation and a norm convergence result for the coefficients is derived. In most of these results, we have to consider Matuszewska–Orlicz indices for the function φ.

关键词： Orlicz spaces extended best polynomial approximation pointwise and norm convergence weak and strong type inequalities Orlicz indices

The Final Origin of Cancer: Molecular Phylogeny

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CellBio 2020年第2期9卷 100-108页

作者： Gamarra Manrique Renzo Reynaldo Doctor in Molecular and Cellular Biology Universidad Nacional San Agustín de Arequipa Arequipa Peru

The expression of cancer is similar to processes that in unicellular organisms grant convenient properties, such as immortality. The presence of oncogenes and proteins in viruses, protozoa and invertebrates is recognized. The study of these characters, at each biological level, represents the way to establish phylogenetic relationships. In unicellular and colonial organisms these characters provide the courage to face a threat. In humans they are inactive and return to express themselves only if there is potential chronic damage. Then they modulate other genes that will respond to the cellular aggressor, leading to unicellular immortality (cancer). It is relevant to evaluate the final or teleological origin of the cancer, which is not currently known. This review provides a theory that would explain why a normal cell becomes neoplastic. Molecular Phylogeny is the final teleological mechanism, whereby transformed cells recapitulate the expression of genes and their products, through molecular maneuvers that assist in responding to adverse factors, referred to as epidemiological levels as risk factors. Self-replication remains the first objective of life on earth. The teleological cause of cancer encompasses this phylogenetic mechanism of damage response. Therefore, I conclude that the final origin of cancer may be a biological adaptation mechanism, called molecular phylogeny. If this theory is verified, it could fill the gap that currently persists on the teleological origin of cancer.

关键词： Cancer Molecular Phylogeny

Isotropic compression behavior of granular assembly with non-spherical particles by X-ray micro-computed tomography and discrete element modeling

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Journal of Rock Mechanics and Geotechnical Engineering 2021年第5期13卷 972-984页

作者： nan Zhang Ahmadreza Hedayat Shaoyang Han Runlin Yang Héctor Gelber Bolaños Sosa Juan JoséGonzález Cárdenas Guido Edgard SalasÁlvarez department of Civil and Environmental Engineering Colorado School of Mines1500 Illinois St.GoldenCO80401USA Key Laboratory of Ministry of Education for Geomechanics and Embankment Engineering Hohai UniversityNanjing210098China School of Civil and Resource Engineering University of Science and Technology BeijingBeijing100083China universidad nacional de san agustín de arequipa ArequipaPeru

The particle morphological properties,such as sphericity,concavity and convexity,of a granular assembly significantly affect its macroscopic and microscopic compressive behaviors under isotropic loading ***,limited studies on investigating the microscopic behavior of the granular assembly with real particle shapes under isotropic compression were *** this study,X-ray computed tomography(mCT)and discrete element modeling(deM)were utilized to investigate isotropic compression behavior of the granular assembly with regard to the particle morphological properties,such as particle sphericity,concavity and interparticle *** mCT was first used to extract the particle morphological parameters and then the deM was utilized to numerically investigate the influences of the particle morphological properties on the isotropic compression *** image reconstruction from mCT images indicated that the presented particle quantification algorithm was robust,and the presented microscopic analysis via the deM simulation demonstrated that the particle surface concavity significantly affected the isotropic compression *** observations of the particle connectivity and local void ratio distribution also provided insights into the granular assembly under isotropic *** found that the particle concavity and interparticle friction influenced the most of the isotropic compression behavior of the granular assemblies.

关键词： X-ray computed tomography(mCT) Discrete element modeling(deM) Isotropic compression Particle surface curvature Particle morphology

Fractions of a chloroform extract of ajenjo leaves (Artemisiamendozana DC. var. mendozana) inhibit the proliferation,viability and clonogenicity of B16-F0 melanoma cells

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BIOCELL 2020年第3期44卷 293-299页

作者： MARÍA ELISA MILLÁn MARÍA FERnAnDA MARRA LEOnARDO AnDRÉS SALVARREDI EMILIO FERnAnDO LIZARRAGA LUIS ALBERTO LOPEZ universidad nacional de Cuyo MendozaArgentina Comisión nacional de Energía Atómica Buenos AiresArgentina Fundación Escuela de Medicina nuclear MendozaArgentina Fundación Miguel Lillo y universidad nacional de Tucumán San Miguel de TucumánArgentina

The ajenjo,Artemisia mendozana ***(Asteraceae),grows in the Andean foothills of Mendoza and san Juan,Argentina,and is used as a medicinal plant for its antispasmodic and antifungal *** aim of this work was to obtain fractions of a chloroform extract of ajenjo leaves and to evaluate the in vitro effects on proliferation,viability and clonogenicity of B16-F0 melanoma *** a silica gel chromatography column,120 fractions were collected and grouped according to the chromatographic profile in 9 main fractions(F1–F9).Their major compounds identified were:terpenes(F1),terpenes and sesquiterpene lactones(F2–F3),sesquiterpenes(F4–F6)and phenols and sesquiterpenes(F7-9).B16-F0 cells were incubated for 72 h with DMSO(vehicle)or 0.1 mg/ml F1–*** 72 h of culture,F1 decreased both the growing index(GI)and cell viability.F2 and F3 both decreased GI and only F3 decreased clonogenic activity.F4 and F5 both decreased *** F5 decreased cell viability and F4 decreased ***,fractions F6–F8 did not affect any of the cell parameters assayed,while F9 decreased cell viability and inhibited clonogenicity.

关键词： Terpenes Sesquiterpene lactones Sesquiterpenes Phenols

Soil organic carbon stocks in native forest of Argentina:a useful surrogate for mitigation and conservation planning under climate variability

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Ecological Processes 2024年第1期13卷 3-24页

作者： Pablo L.Peri Juan Gaitán Matías Mastrangelo Marcelo nosetto Pablo E.Villagra Ezequiel Balducci Martín Pinazo Roxana P.Eclesia Alejandra Von Wallis Sebastián Villarino Francisco Alaggia Marina González Polo Silvina Manrique Pablo A.Meglioli Julián Rodríguez-Souilla Martín Mónaco Jimena E.Chaves Ariel Medina Ignacio Gasparri Eugenio Alvarez Arnesi María Paula Barral Axel von Müller norberto M.Pahr Josefina Uribe Echevarria Pedro Fernández Marina Morsucci Dardo López Juan Manuel Cellini Leandro Alvarez Ignacio Barberis Hernán Colomb Ludmila La Manna Sebastián Barbaro Cecilia Blundo Ximena Sirimarco Laura Cavallero Gualberto Zalazar Guillermo Martínez Pastur Instituto nacional de Tecnología Agropecuaria (InTA) universidad nacional de la Patagonia Austral (UnPA) Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET ) universidad nacional de Luján Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET ) Grupo de Estudio de Agroecosistemas y Paisajes Rurales (GEAP) Universidad Nacional de Mar del Plata Consejo Nacional de Investigaciones Científicas y Técnicas(CONICET ) CCT san Luis Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET ) Instituto Argentino de nivología Glaciología y Ciencias Ambientales (IANIGLA) Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET ) Universidad Nacional de Cuyo Instituto de Investigaciones en Biodiversidad y Medioambiente (InIBIOMA) Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET ) Instituto de Investigaciones en Energía no Convencional CCT Salta-JujuyConsejo Nacional de Investigaciones Científicas y Técnicas (CONICET ) Laboratorio de Recursos Agroforestales Centro Austral de Investigaciones Científicas (CADIC) Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET ) Dirección nacional de Bosques Ministerio de Ambiente y Desarrollo Sostenible de la Nación Instituto de Ecología Regional Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET )Universidad Nacional de Tucumán universidad nacional de Rosario Instituto de Investigaciones en Ciencias Agrarias de Rosario Centro Científico Tecnológico CONICET Grupo de Estudio de Agroecosistemas y Paisajes Rurales (GEAP) Universidad Nacional de Mar del Plata Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET ) Laboratorio de Investigaciones en Maderas (LIMAD) Universidad Nacional de La Plata (UNLP) Administración de Parques nacionales (APn) Parque Nacional Los Alerces Centro de Estudios Ambientales Integrados (CEAI) Universidad Nacional de la Patagonia San Juan Bosco (UNPASJB) Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET )

Background The nationally determined contribution（nDC） presented by Argentina within the framework of the Paris Agreement is aligned with the decisions made in the context of the United nations Framework Conven-tion on Climate Change（UnFCCC） on the reduction of emissions derived from deforestation and forest degradation, as well as forest carbon conservation（REDD+）. In addition, climate change constitutes one of the greatest threats to forest biodiversity and ecosystem services. However, the soil organic carbon（SOC） stocks of native forests have not been incorporated into the Forest Reference Emission Levels calculations and for conservation planning under cli-mate variability due to a lack of information. The objectives of this study were:（i） to model SOC stocks to 30 cm of native forests at a national scale using climatic, topographic and vegetation as predictor variables, and（ii） to relate SOC stocks with spatial–temporal remotely sensed indices to determine biodiversity conservation concerns due to threats from high inter-annual climate *** We used 1040 forest soil samples（0–30 cm） to generate spatially explicit estimates of SOC native forests in Argentina at a spatial resolution of approximately 200 m. We selected 52 potential predictive environmental covari-ates, which represent key factors for the spatial distribution of SOC. All covariate maps were uploaded to the Google Earth Engine cloud-based computing platform for subsequent modelling. To determine the biodiversity threats from high inter-annual climate variability, we employed the spatial–temporal satellite-derived indices based on Enhanced Vegetation Index（EVI） and land surface temperature（LST） images from Landsat *** SOC model（0–30 cm depth） prediction accounted for 69% of the variation of this soil property across the whole native forest coverage in Argentina. Total mean SOC stock reached 2.81 Pg C（2.71–2.84 Pg C with a probability of 90%） for a total area of 460,790 km2,

关键词： Soil organic carbon Biodiversity native forest Climate change mitigation Modelling Resilience

Annual variation of adult survival of a south-temperate House Wren population in Argentina

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Avian Research 2024年第2期15卷 229-237页

作者： Gustavo J.Fernandez Mariana E.Carro Paulo E.Llambías Grupo de Investigacion en Ecofisiología de Fauna Silvestre INIBIOMA-CONICETAsentamiento Universitario San Martín de los Andes(AUSMA)Universidad Nacional Del ComahuePasaje de la Paz 235(8370)San Martín de los AndesNeuquenArgentina Grupo de Investigacion de Biología de Aves IADIZA CCT-MendozaUniversidad Nacional de CuyoAvenida RuizLeal s/n Parque General San Martin5500MendozaArgentina

Identifying factors affecting the survival of individuals is essential for understanding the evolution of life-history traits and population *** numerous studies on this subject in north-temperate environments,there is a lack of equivalent studies at similar latitudes in the ***,we used a 14-year dataset of capture,banding,and resighting to estimate the annual variation in the apparent adult survival probability of a south-temperate population of House Wrens(Troglodytes aedon bonariae).We evaluated temporal variation in sur-vival and the effect of environmental(climatic)and demographic variables(adult abundance,total number of fledglings produced during each breeding season)on survival *** found that the probability of adult survival decreased as the abundance of breeding adults *** density-dependent effect could be related to the resident lifestyle of southern House Wrens,which could determine an intense competition for territories and resources that ultimately would affect their survival.

关键词： Annual variation CJS density-dependence Survival Troglodytes aedon bonariae

Green Method, Optical and Structural Characterization of ZnO nanoparticles Synthesized Using Leaves Extract of M. oleifera

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Journal of Renewable Materials 2022年第3期10卷 833-847页

作者： Jose Vulfrano Gonzalez-Fernandez Diego David Pinzon-Moreno Antony Alexander neciosup-Puican Maria Veronica Carranza-Oropeza Facultad de Quimica e Ingenieria Quimica Universidad Nacional Mayor de San MarcosLima15081Peru Centro de Investigaciones Tecnologicas Biomedicas y MedioambientalesUniversidad Nacional Mayor de San MarcosLima15081Peru

ZnO nanoparticles(ZnO-nP)present innovative optical,electrical,and magnetic properties that depend on spe-cific characteristics,e.g.,size,distribution,and ***,these properties are essential to address various applications in areas such as electronics,medicine,energy,and *** addition,the performance of this ZnO-nP depends of their preparation which can be done by chemical,physical,and biological ***,nowadays,the main interest in developing ZnO-nP synthesis through biological methods bases on the decrease of use of toxic chemicals or energy applied to the procedures,making the process more cost-effective and environ-mentally ***,the large-scale production of nanoparticles by green synthesis remains a big challenge due to the complexity of the biological extracts used in chemical *** being the case,the preparation of ZnO-nP using Moringa oleifera extract as an alternative biological agent for capping and reduction in synthesis was evaluated in this ***,the results based on the analysis of the optical and structural characterization of the ZnO-nP obtained by employing UV-Vis,DLS,zeta potential,XRD,ATR-FTIR,and FE-SEM indicate mostly the presence of spherical nanosized material with a mean hydrodynamic diameter of 47.2 nm measured by DLS and a mean size diameter of 25 nm observed with FE-SEM ***,in FE-SEM images a homo-geneous dispersion and distribution is observed in the absence of agglutination,agglomeration,or generation of significant lumps of the *** XRD analysis showed that heat annealing induced the crystallite size favor-ing their *** obtained data confirm the synthesis of ZnO-nP and the absence of impurities associated with organic compounds in the annealed ***,those results and low-cost production pre-sent to the synthesized ZnO-nP by this biological method as a useful material in several applications.

关键词： ZnO nanoparticles green chemistry Moringa oleifera extract optical characterization structural characterization