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Did maize domestication and early spread mediate the population genetics of corn leafhopper?

Insect Science 2019年第3期26卷 569-586页

作者： Julio S. Bernal Amanda M. Davila-Flores Raul F. Medina yolanda H. Chen Kyle E. Harrison Kimberly A. Berrier Department of Entomology Texas A&M University College Station Texas USA Department of Plant and Soil Sciences University of Vermont Burlington Vermont USA

Investigating how crop domestication and early farming mediated crop attributes, distributions, and interactions with antagonists may shed light on today's agricultural pest problems. Crop domestication generally involved artificial selection for traits desirable to early farmers, for example, in creased productivity or yield, and enhanced qualities, though invariably it altered the interactions between crops and insects, and expanded the geographical ranges of crops. Thus, some studies suggest that with crop domestication and spread, insect populations on wild crop ancestors gave rise to pestiferous insect populations on crops. Here, we addressed whether the emergence of corn leafhopper (Dalbulus ma id is) as an agricultural pest may be associated with domestication and early spread of maize (Zea mays mays). We used AFLP markers and mitochondrial COI sequences to assess population genetic structuring and haplotype relationships among corn leafhopper samples from maize and its wild relative Zea diploperennis from multiple locations in Mexico and Argentina. We uncovered seven corn leafhopper haplotypes contained within two haplogroups, one haplogroup containing haplotypes associated with maize and the other containing haplotypes associated with Z. diploperennis in a mountainous habitat. Within the first haplogroup, one haplotype was predominant across Mexican locations, and another across Argentinean locations;both were considered pestiferous. We suggested that the divergence times of the maize-associated haplogroup and of the "pestiferous" haplotypes are correlated with the chronology of maize spread following its domestication. Overall, our results support a hypothesis positing that maize domestication favored corn leafhopper genotypes preadapted for exploiting maize so that they became pestiferous, and that with the geographical expansi on of maize farming, corn leafhopper colonized Z. diploperennis, a host exclusive to secluded habitats that serves as a refuge fo

关键词： Dalbulus maidis haplotype network analysis perennial teosinte population genetic structuring Zea diploperennis Zea mays mays

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Protective Green Patinas on Copper in Outdoor Constructions

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Journal of Environmental Protection 2011年第7期2卷 956-959页

作者： yolanda Hedberg Inger Odnevall Wallinder 不详

The last 15 years of research related to atmospheric corrosion and the release of copper to the environment are shortly summarized. Brown and green patinas with high barrier properties for corrosion are gradually evolved on copper at atmospheric conditions. The corrosion process and repeated dry and wet cycles results in a partial dissolution of corrosion products within the patina. Dissolved copper can be released and dispersed into the environment via the action of rainwater, however the major part is rearranged within the patina during drying cycles. The majority of corrosion products formed have a poor solubility, very different from water soluble copper salts. The release process is very slow and takes place independent of patina color. Its extent has only a marginal effect on the adherent patina. Released copper rapidly interacts with organic matter and in contact with different surfaces already in the close vicinity of the building, such as drainage systems, storm water pipes, pavements, stone materials and soil systems. These surfaces all have high capacities to retain copper in the runoff water and to reduce its concentration and chemical form to non-available and non-toxic levels for aquatic organisms.

关键词： Copper Runoff Patina

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Pressurized Liquid Extraction of Pigments from Chlamydomonas *** Chemical Characterization by HPLC–MS/MS

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Journal of Analysis and Testing 2018年第2期2卷 149-157页

作者： Lidia Montero Mahshid Sedghi yolanda García Carlos Almeida Carl Safi Nicole Engelen‑Smit Alejandro Cifuentes Jose A.Mendiola Elena Ibáñez Applied Analytical Chemistry University of Duisburg-EssenUniversitaetsstr.545141 EssenGermany Laboratory of Foodomics Bioactivity and Food Analysis DepartmentInstitute of Food Science Research CIAL(CSIC-UAM)Campus de CantoblancoC/Nicolás Cabrera 928049 MadridSpain Spanish Bank of Algae Instituto de Oceanografía y Cambio GlobalFundación Canaria Parque Científico‑TecnológicoUniversidad de Las Palmas de Gran CanariaMuelle de Taliarte s/n35214 Telde(Canary Islands)Spain Wageningen Food and Biobased Research Wageningen University and ResearchPO Box 176700 AA WageningenThe Netherlands

Pressurized liquid extraction using green solvents(ethanol and water)was applied to extract photosynthetic pigments from the microalgae Chlamydomonas *** experimental design is employed to determine the effect of the extraction conditions on the extraction yield and the antioxidant capacity of the different extracts determined using 1,1-diphenyl-2-picryl-hydrazyl and TEAC *** the extracts show significant antioxidant activity in all ***,in this work,the carotenoid and chlorophyll composition of the Chlamydomonas extracts was analyzed by HPLC–DAD–APCI–MS/MS for the first time,being the main compounds lutein and pheophythin a′.

关键词： Antioxidant capacity Chlamydomonas sp. HPLC–DAD–APCI–MS/MS Pigments Pressurized liquid extraction Carotenoids

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Tentative Identification of Phytochemicals and Antioxidant Activities during Fruit-Ripening on Chamaedorea radicalis Mart.

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Phyton-International Journal of Experimental Botany 2020年第2期89卷 361-373页

作者： Gerardo Montelongo-Ruiz yolanda del Rocio Moreno-Ramirez Maria Cruz Juarez-Aragon NohemiNino-Garcia Reyna Ivonne Torres-Acosta Torres-Castillo Jorge Ariel Universidad Autonoma de Tamaulipas Instituto de Ecologia AplicadaCiudad Victoria87019Mexico Universidad Autonoma de Tamaulipas Unidad Academica Multidisciplinaria ManteCiudad Mante89840Mexico

This work aims to determine the phytochemical characterization of the pericarp of Chamaedorea radicalis *** as a non-timber product with potential to obtain phytochemicals with potential applications in the *** from *** were grouped in four ripening stages named as S1,S2,S3 and S4,according to maturity;S1 the most unripe stage and S4 the completely ripe *** of total phenolic compounds,free radical scavenging activities and total flavonoid contents using spectrophotometric methods were ***,the tentative identification of phytochemicals during fruit ripening was done using *** phenolic compound(TPC)content ranged from 7.24 to 12.53 mg gallic acid equivalents per gram of fresh weight(mg GAE/g FW).Total flavonoids(TF)contents ranged from 0.163 to 0.23 mg of quercetin equivalents per g FW(mg QE/g FW).Free radical scavenging activity against DPPH and ABTS radicals varied from 40.80 to 53.68 and from 22.29 to 37.76 mmol Trolox equivalents g FW(mmol TE/g FW),*** assay in vitro by FRAP(ferric reducing antioxidant power)method showed that S3 was the highest level with antioxidant power while S4 was the lowest with Red ripeness stage showed the lowest contents for all *** spectrometry allowed detection of 26 compounds,including phenolics,alkaloids and ***,Kaempferol 3-neohesperidoside and the four saponins identified were present in all ripeness *** phytochemical identification and the spectrophotometric determinations showed that the pericarp of *** presented antioxidants and compounds related to alkaloids,phenolics and *** presence and abundance of each phytochemical regarding each ripeness stage should be considered.

关键词： Metabolite identification palm free radical scavenging phenolic compounds saponins

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Characterization of the Atmospheric Dynamics in Riobamba City Using the Chaos Theory

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Atmospheric and Climate Sciences 2015年第4期5卷 441-449页

作者： Arquímides Haro Cecilia Limaico yolanda Llosas Physics and Mathematics School Polytechnic School of Chimborazo Riobamba Ecuador Faculty of Engineering National University of Chimborazo Riobamba Ecuador Department of Automatic Control East University Santiago Cuba

Chaos studies all that is messy, disorganized and incoherent;mathematically the chaos is a dynamic system governed by nonlinear differential equations. Chaos has an unpredictable behavior;its dynamical is very sensitive to the initial conditions. Atypical chaotic system is the atmosphere;this limits the knowledge about its behavior;but with the advance in the computers, the results that are obtained with the chaos theory improved significantly;the description of atmosphera and its results have extended to other fields of the science, as the economy, health and others. The object of this work was to determine the atmospheric dynamics in the Riobamba city using the theory of chaos, with meteorological data of the meteorological station of the ESPOCH of one year (2010) of data that were processed with model TISEAN. The results determine a hyperchaotic system, according to the coefficients of Lyapunov.

关键词： Chaos Theory Atmospheric Variables Coefficients of Lyapunov Dynamics Entropy

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Postnatal development of fetuses with a single umbilical artery:differences between malformed and non-malformed infants

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World Journal of Pediatrics 2015年第1期11卷 61-66页

作者： Jose Vicente Arcos-Machancoses Purificación Marín-Reina Eugenia Romaguera-Salort yolanda García-Camuñas Antonio Pérez-Aytés Máximo Vento Department of Pediatrics University & Polytechnic Hospital La Fe Valencia Spain Division of Neonatology University & Polytechnic Hospital La Fe Valencia Spain Department of Obstetrics & Gynecology University & Polytechnic Hospital La Fe Valencia Spain Division of Dysmorphology & Reproductive Assessment University & Polytechnic Hospital La Fe Valencia Spain

Background:The presence of a single umbilical artery(SUA)is a fetal soft marker of congenital *** the most common related malformations,there are cardiological,nephrourological and digestive anomalies,most of which are considered to have a vascular *** is an association between increased incidence of intrauterine growth retardation and adverse perinatal indicators,but whether this association is due to related anomalies or isolated SUA(SUA)is ***:We reviewed 96 cases of iSUA and non-isolated SUA(niSUA),diagnosed in a period of two years in a referral hospital for high-risk *** on prenatal explorations,including fetal ultrasonography and karyotyping,were *** was diagnosed when no malformations were found prenatally or in postnatal ***:Sixty-six newborns(68.8%)had no other anomalies and 30(31.3%)presented with a variety of malformations including heart diseases,urophaties,digestive,nervous and musculoskeletal disorders,genetic abnormalities and complex *** and nephrourological abnormalities were found to be the most frequent association with a SUA(both in 23.8%of malformed SUA newborns).Intrauterine growth restriction was not higher in iSUA newborns than in a normal *** allowed optimal prenatal diagnosis in most ***:The prognosis of the fetus with a SUA is determined by the presence of other malformations observed by an expert *** no other findings are made,only a routine physical examination should be performed in newborns,but no other complementary examinations are required.

关键词： cardiovascular abnormalities congenital abnormalities fetal growth retardation prenatal ultrasonography single umbilical artery

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Thermal Flows in the Surface Atmosphere of the Riobamba City

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Atmospheric and Climate Sciences 2014年第4期4卷 679-684页

作者： Arquímides Haro Cecilia Limaico yolanda Llosas Physics and Mathematical School Polytechnic School of Chimborazo Riobamba Ecuador Department of Automatic Control East University Santiago Cuba

This study evaluated the behavior of surface heat fluxes, in the meteorological and physical conditions of the Riobamba city (height of 2754 m regarding the sea level, geographical position 1°58'58'' Sour of latitude and 78°39'33'' West of longitude, and it is located in the Ecuadorian inter-Andean alley), these meteorological data were monitored at the ESPOCH stations of the alternative energy group during 2010-2012, and applied information processing dynamic model formulated by Van Ulden and Hostlag, which allows the determination of heat flow of sensible heat, latent heat and surface heat generated in the interaction soil-air. The measures allow us to know the average behavior of the heat flow data with variation between, 38.22, 22.15 and 155.20 W/m2 for the latent, sensible and surface heat respectively, while during the day hours significant variations in these flows that reach maximum values during the day with 139, 127 and 763 W/m2 and minimum at the night -3.9, -27.5 and -263.3 W/m2;results differ from those obtained under normal conditions at sea level.

关键词： Thermal Flows Radiation Latent Heat Surface Heat Sensible Heat

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Large-scale dendrimer-based uneven nanopatterns for the study of local arginine-glycine-aspartic acid （RGD） density effects on cell adhesion

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Nano Research 2014年第3期7卷 399-409页

作者： Anna Lagunas Albert G. Castano Juan M. Artes yolanda Vida Daniel Collado Ezequiel Perez-lnestrosa Pau Gorostiza Silvia Claros Jose A. Andrades Josep Samitier Networking Biomedical Research Center in Bioengineering Biomaterials and Nanomedicine (CIBER-BBN) Spain Institute for Bioengineering of Catalonia (IBEC) Baldiri-Reixac 15-2 1 Barcelona 08028 Spain Physical Chemistry Department University of Barcelona (UB) Martii Franques 1-11 Barcelona 08028 Spain Andalusian Centre for Nanomedicine and Biotechnology (BIONAND) Severo Ochoa 35 Mdlaga 29590 Spain Organic Chemistry Department University of Mdlaga (UMA) Campus Teatinos Malaga 29071 Spain Institucio Catalana de Recerca i Estudis Avanats (ICREA) Spain Cell Biology Genetics and Physiology Department University of Malaga (UMA) Campus Teatinos Malaga 29071 Spain Electronics Department University of Barcelona (UB) Martii Franques 1-11 Barcelona 08028 Spain t Present address: Electrical and Computer Engineering Department University of California Davis 95616 Davis CA USA

Cell adhesion processes are governed by the nanoscale arrangement of the extracellular matrix （ECM）, being more affected by local rather than global concentrations of cell adhesive ligands. In many cell-based studies, grafting of dendrimers on surfaces has shown the benefits of the local increase in concentration provided by the dendritic configuration, although the lack of any reported surface characterization has limited any direct correlation between dendrimer disposition and cell response. In order to establish a proper correlation, some control over dendrimer surface deposition is desirable. Here, dendrimer nanopatterning has been employed to address arginine-glycine-aspartic acid （RGD） density effects on cell adhesion. Nanopatterned surfaces were fully characterized by atomic force microscopy （AFM）, scanning tunneling microscopy （STM） and X-ray photoelectron spectroscopy （XPS）, showing that tunable distributions of cell adhesive ligands on the surface are obtained as a function of the initial dendrimer bulk concentration. Cell experiments showed a clear correlation with dendrimer surface layout： Substrates presenting regions of high local ligand density resulted in a higher percentage of adhered cells and a higher degree of maturation of focal adhesions （FAs）. Therefore, dendrimer nano- patterning is presented as a suitable and controlled approach to address the effect of local ligand density on cell response. Moreover, due to the easy modification of dendrimer peripheral groups, dendrimer nanopatterning can be further extended to other ECM ligands having density effects on cells.

关键词： dendrimer arginine-glycine-asparticacid atomic force microscopy scanning tunnelingmicroscopy cell adhesion focal adhesions

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Particle Characteristics and Metal Release From Natural Rutile (TiO<sub>2</sub>) and Zircon Particles in Synthetic Body Fluids

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Journal of Biomaterials and Nanobiotechnology 2012年第1期3卷 37-49页

作者： yolanda Hedberg Jonas Hedberg Inger Odnevall Wallinder Division of Surface and Corrosion Science Department of Chemistry Royal Institute of Technology (KTH) Stockholm Sweden

Titanium oxide (rutile, TiO2) and zircon (ZrSiO4), known insoluble ceramic materials, are commonly used for coatings of implant materials. We investigate the release of zirconium, titanium, aluminum, iron, and silicon from different micron-sized powders of 6 powders of natural rutile (TiO2) and zircon (ZrSiO4) from a surface perspective. The investigation includes five different synthetic body fluids and two time periods of exposure, 2 and 24 hours. The solution chemicals rather than pH are important for the release of zirconium. When exceeding a critical amount of aluminum and silicon in the surface oxide, the particles seem to be protected from selective pH-specific release at neutral or weakly alkaline pH. The importance of bulk and surface composition and individual changes between different kinds of the same material is elucidated. Changes in material properties and metal release characteristics with particle size are presented for zircon.

关键词： Rutile Zircon Metal ion release Particles Surface analysis

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The Farallon-Aluk ridge collision with South America:Implications for the geochemical changes of slab window magmas from fore- to back-arc

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Geoscience Frontiers 2013年第4期4卷 377-388页

作者： Eugenio Aragón Lucio Pinotti Fernando D'Eramo Antonio Castro Osvaldo Rabbia Jorge Coniglio Manuel Demartis Irene Hernando Claudia E.Cavarozzi yolanda E.Aguilera Centro de Investigaciones Geologicas(UNLP-CONICET) 1 N°644(1900) La Plata.Buenos Aires.Argentina Facultad de Ciencias Naturales y Museo Universidad Nacional de la Plata122 y 60s/n.(1900).La PlataBuenos AiresArgentina Departamento de Geologia.Universidad Nacional de Rio Cuarto.(UNRC-CONICET).Ruta 36 km 601.Rio Cuarto.Cordoba.Argentina Departamento de Geologia.Universidad de Huelva.21071 Huelva.Spain Instituto de Geologia Economica Aplicada.Universidad de Concepcion.Concepcion.Chile Departamento de Geologia.Universidad Nacional de Rio Cuarto.(UNRC-CONICET) Ruta 36 km 601.Rio Cuarto.CordobaArgentina Centro de Investigaciones Geologicas(UNLP-CONICET).1 N°644.(1900) La Plata.Buenos Aires.Argentina Facultad de Ciencias Naturales y Museo.Universidad Nacional de la Plata.122 y 60 s/n.(1900).La PlataBuenos Aires.Argentina Facultad de Ciencias Naturales y Museo.Universidad National dela Plata.122 y 60 s/n(1900)La Plata.Buenos Aires.Argentina Direccion de Aplicacion de Imagenes Satelitarias(M.O.S.P.).58 e/ 7 y 8.piso 2.1900 La Plata.Buenos Aires.Argentina

The collision of a divergent ocean ridge may evolve into two end cases： in the continuity of ocean-floor subduction, or in the detachment of the subducted plate. The northern Patagonia active plate margin has the unique situation that in Cenozoic time it has been subjected to two divergent ridge collisions, each one representing one of the end members. The Neogene Antarctica-Nazca divergent ridge collision evolved as a continuous ocean-floor subduction system, promoting a magmatic hiatus at the arc axis, the obduction of part of the ridge ocean-floor in the fore-arc, and basaltic volcanism in the back-arc. In contrast, the Paleogene Farallon-Aluk divergent ridge collision evolved into a transform margin, with the detachment and sinking of the Aluk plate and the development of a large slab window. As in the previous case, this collision promoted a magmatic hiatus at the arc axis, but the tectono-magmatic scenario changed to postorogenic synextensional volcanism that spread to the former fore-arc （basalt, andesite, rhyolite） and former back-arc （bimodal ignimbrite flare-up, basalt）. Geochemistry of this slab window synextensional volcanism shows more MORB-like basalts towards the former fore-arc, and MORB-OIB-Iike basalts towards the former back-arc. Instead, an isolated undeformable crustal block in the former back-arc, with an ＂epeirogenic＂ response to the slab window and extensional regime, was covered by OIB-type basalts after uplift. Major elements show that slab window basalts reach TiO2 values up to 3 wt%, as compared with the top value of 1.5 wt% of arc magmas. Besides, the MgO with respect to （FeOt ＋ A1203） ratio helps to distinguish slab window magma changes from the former fore-arc to the former back-arc and also with respect to the ＂epeirogenic＂ block. Higher contents of HFS elements such as Nb and Ta also help to distinguish this slab window from arc magmas and also, to distinguish slab window magma changes from the former fore-arc to the former back-arc

关键词： AndesActive ridge collisionSubduction-transform transitionSlab window volcanismSynextensional calc-alkalineBimodal volcanism

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