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Arthropods on plants in a fragmented Neotropical dry forest： A functional analysis of area loss and edge effects

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Insect Science 2015年第1期22卷 129-138页

作者： Ezequiel Gonzalez Adriana Salvo Graciela Valladares Centro de Investigaciones Entomol6gicas de C6rdoba (IMBIV - conicet) and Universidad Nacional de C6rdoba C6rdoba Argentina

Loss and fragmentation of natural ecosystems are widely recognized as the most important threats to biodiversity conservation, with Neotropical dry forests among the most endangered ecosystems. Area and edge effects are major factors in fragmented landscapes. Here, we examine area and edge effects and their interaction, on ensembles of arthropods associated to native vegetation in a fragmented Chaco Serrano forest. We analyzed family richness and community composition of herbivores, predators, and parasitoids on three native plant species in 12 fragments of varying size and at edge/interior positions. We also looked for indicator families by using Indicator Species Analysis. Loss of family richness with the reduction of forest fragment area was observed for the three functional groups, with sirnilar magnitude. Herbivores were richer at the edges without interaction between edge and area effects, whereas predators were not affected by edge/interior position and parasitoid richness showed an interaction between area and position, with a steeper area slope at the edges. Family composition of herbivore, predator, and parasitoid assemblages was also affected by forest area and/or edge/interior situation. We found three indicator families for large remnants and five for edges. Our results support the key role of forest area for conservation of arthropods taxonomic and functional diversity in a highly threatened region, and emphasize the need to understand the interactions between area and edge effects on such diversity.

关键词： area loss Chaco Serrano edge effect forest arthropods functional groups habitat fragmentation

Nanosized magnetite in low cost materials for remediation of water polluted with toxic metals, azo- and antraquinonic dyes

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Frontiers of Environmental Science & Engineering 2015年第5期9卷 746-769页

作者： Maria Fernanda HORST Veronica LASSALLE Maria Lujan FERREIRA Institute of Chemistry of the South (Inquisur Universidad Nacional del Sur~ONICET) Avda Alem 1253 Bahia Blanca Argentina Pilot Plant of Chemical Engineering (PLAPIQUI-UNS-conicet) Universidad Nacional del Sur--CONICET Camino La Carrindanga km7 Bahia Blanca Argentina

Nanosized magnetite has emerged as an adsorbent of pollutants in water remediation. Nanoadsor- bents include magnetic iron oxide and its modifiers/ stabilizers, such as carbon, silica, clay, organic moieties （polymers, aminoaeids, and fatty acids） and other inorganic oxides. This review is focused on the recent developments on the synthesis and use of magnetic nanoparticles and nanocomposites in the treatment of contaminated water. The emphasis is on the influence of the iron oxide modifiers on some properties of interest such as size, BET area, and magnetization. The characteristics of these nanomaterials are related to their ability to eliminate heavy metal ions and dyes from wastewater. Comparative analysis of the actual literature was performed aiming to present the magnetic material, its preparation methodology and performance in the elimination of the selected pollutants. Vast information has been properly summarized according to the materials, their properties and preferential affinity for selected contaminants. The mechanisms governing nanomaterial＇s formation as well as the interactions with heavy metals and dyes have been carefully analyzed and associated to their efficiency.

关键词： nanomagnetite water remediation toxicmetals dyes supported magnetite

Insights into induction of the immune response by the hepatitis B vaccine

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World Journal of Gastroenterology 2022年第31期28卷 4249-4262页

作者： Federico Alejandro Di Lello Alfredo Pedro Martínez Diego Martín Flichman Microbiology Universidad de Buenos Aires.Facultad de Farmacia y Bioquímica.Instituto de Investigaciones en Bacteriología y Virología MolecularBuenos Aires C1113AADArgentina Consejo Nacional de Investigaciones Científicas y Técnicas Buenos Aires C1425FQBArgentina Virology Section Centro de Educación Médica e Investigaciones Clínicas Norberto Quirno“CEMIC”Buenos Aires C1431FWOArgentina Microbiology Universidad de Buenos AiresInstituto de Investigaciones Biomédicas en Retrovirus y Síndrome de Inmunodeficiencia AdquiridaBuenos Aires C1121ABGArgentina

After more than four decades of hepatitis B virus(HBV)vaccine implementation,its safety and efficacy in preventing HBV infection have been proven and several milestones have been *** countries have included HBV immunization schedules in their health policies and progress has been made regarding universalization of the first HBV vaccine dose at *** of these actions have significantly contributed to reducing both the incidence of HBV infection and its related ***,there are still many drawbacks to *** main concerns are the deficient coverage rate of the dose at birth and the large adult population that has not been reached timely by universal ***,the current most widely used second-generation vaccines do not induce protective immunity in 5%to 10%of the population,particularly in people over 40-years-old,obese(body mass index>25 kg/m2),heavy smokers,and patients undergoing dialysis or infection with human immunodeficiency *** developed and approved novel vaccine formulations using more potent adjuvants or multiple antigens have shown better performance,particularly in difficult *** advances re-launch the expectations of achieving the World Health Organization’s objective of completing hepatitis control by 2030.

关键词： Hepatitis B virus Vaccine Immune response Antibodies Neutralizing

Sharp Bounds for Fractional One-sided Operators

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Acta Mathematica Sinica,English Series 2016年第11期32卷 1255-1278页

作者： Maria Silvina RIVEROS Raul Emilio VIDAL FaMAF-CIEM UNC-CONICET Ciudad Universitaria 5000 Cdrdoba Argentina

In this paper, we characterize the sharp boundedness of the one-sided fractional maximal function for one-weight and two-weight inequalities. Also a new two-weight testing condition for the one-sided fractional maximal function is introduced extending the work of Martin-Reyes and de la Torre. Improving some extrapolation result for the one-sided case, we get weak sharp bounded estimates for one-sided fractional maximal function and weak and strong sharp bounded estimates for one-sided fractional integral.

关键词： One-sided fractional integrals one-sided maximal fractional function extrapolation Saw-yer weights

Differential responses to artificial selection on oviposition site preferences in Drosophila melanogaster and D. simulans

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Insect Science 2015年第6期22卷 821-828页

作者： Eduardo M. Soto Maria I. L. Betti Juan Hurtado Esteban Hasson Departamento de Ecologia Genetica y Evolucion IEGEBA (CONICET-UBA) Facultad de Ciencias Exactas y Naturales Universidad deBuenos Aires Buenos Aires Argentina

The preference-performance relationship in plant-insect interactions is a cen- tral theme in evolutionary ecology. Among many insects, eggs are vulnerable and larvae have limited mobility, making the choice of an appropriate oviposition site one of the most important decisions for a female. We investigated the evolution of oviposition preferences in Drosophila melanogaster Meigen and Drosophila simulans Sturtevant by artificially selecting for the preference for 2 natural resources, grape and quince. The main finding of our study is the differential responses of D. melanogaster and D. simulans. Although preferences evolved in the experimental populations of D. melanogaster, responses were not consistent with the selection regimes applied. In contrast, responses in D. simulans were consistent with expectations, demonstrating that this species has selectable genetic variation for the trait. Furthermore, crosses between D. simulans divergent lines showed that the genetic factors involved in grape preference appear to be largely recessive. In summary, our artificial selection study suggests that D. melanogaster and D. simulans possess different genetic architectures for this trait.

关键词： artificial selection behavior Drosophila genetic variation naturalresources oviposition preference

Organic coating of 1-2-nm-size silicon nanoparticles： Effect on particle properties

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Nano Research 2015年第6期8卷 2047-2062页

作者： Cristian R. Lillo Juan J. Romero Manuel Llansola Portoles Reinaldo Pis Diez Paula Caregnato Monica C. Gonzalez Instituto de Investigaciones Fisicoquimicas Teoricas y Aplicadas (INIFTA) CCT-La Plata-CONICET Facultad de Ciencias Universidad National de La Plata cc 16 Suc. 4 1900 La Plata Argentina CEQUINOR CCT-La Plata-CONICET Facultad de Ciencias Exactas Universidad Nacional de La Plata cc 9621900 La Plata Argentina Department of Chemistry and Biochemistry Center for Bioenergy and Photosynthesis Arizona State University Tempe Arizona USA

Photoluminescent silicon nanoparticles 1-2 nm in size were synthesized by a wet chemical procedure and derivatized with propylamine （NH2SiNP）. Surface NH2 groups were used as linkers for additional poly（ethylene glycol）（PEG） and folic acid （Fo） attachment （PEG-NHSiNP and Fo-NHSiNP, respectively） to enable efficient targeting of the particles to tumors and inflammatory sites. The particles were characterized by transmission electron microscopy, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, ζ potential, dynamic light scattering, and time-resolved anisotropy. The photophysical properties and photosensitizing capacity of the particles and their interaction with proteins was dependent on the nature of the attached molecules. While PEG attachment did not alter the photophysical behavior of NH2SiNP, the attachment of Fo diminished particle photoluminescence. Particles retained the capacity for 1O2 generation; however, efficient 1O2 quenching by the attached surface groups may be a drawback when using these particles as 1O2photosensitizers. In addition, Fo attachment provided particles with the capacity to generate the superoxide anion radical （O2-）. The particles were able to bind tryptophan residues of bovine serum albumin （BSA） within quenching distances. NH2SiNP and PEG-NHSLNP ground state complexes with BSA showed binding constants of （3.1 ± 0.3） × 10^4 and （1.3 ±0.4） × 10^3 M-1, respectively. The lower value observed for PEG-NHSiNP complexes indicates that surface PEGylation leads to a reduction in protein adsorption, which is required to prevent opsonization. An increase in particle luminescence upon BSA binding was attributed to the hydrophobic environment generated by the protein. NH2SiNP-BSA complexes were also capable of resonance energy transfer.

关键词： propylamine folic acid poly(ethylene glycol) photoluminescence protein-binding singlet oxygen

Kinetic Study on CO_2 Reforming of Methane

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Chinese Journal of Chemical Engineering 2001年第2期9卷 190-195页

作者： C.E.Quincoces M.G.González CINDECA Ctr Invest & Desarrollo Proc Catal RA-1900 La Plata Argentina

The kinetics of CO2 reforming of methane has been studied at 976－1033K on a commercial NiO/CaO/Al2O3 catalyst in a packed-bed continuous reactor. The reaction was carried out at atmospheric pressure and CO2/CH4 ratio ＞ 2. The Hougen-Watson rate models were fitted to experimental data assuming the disso ciative adsorption of methane as the rate-determining step. The reaction rate showed an effective reaction order of about unity for CH4. The apparent activity energy was found to be 104 kJ·mol-1. Therefore the kinetic reaction parameters were determined and a possible reaction mechanism was proposed.

关键词： CH4 reforming Ni catalysts syngas

Elevation transition of aquatic insects closely matches a thermal feature in the Yungas of Northwestern Argentina

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Journal of Mountain Science 2024年第2期21卷 433-448页

作者： Alexandra BUITRAGO-GUACANAME Carlos MOLINERI Andrés LIRA-NORIEGA Daniel Andrés DOS SANTOS Neotropical Biodiversity Institute(conicet-UNT) UNT-DomesHorco Molle S/N4107 TucumánArgentina CONACYT Research Fellow Network of Advanced Molecular StudiesInstitute of Ecology A.COld Road to Coatepec 351El HayaCP 91073XalapaVeracruzMexico Biostatistics Chair Faculty of Natural Sciences and IMLNational University of TucumánSan Miguel de TucumánMiguel Lillo 2054000 TucumánArgentina

Temperature is a key factor that shapes the distribution of *** knowledge about how species respond to temperature is relevant to devise strategies for addressing the impacts of climate *** insects are particularly vulnerable to climate change,yet there is still much to learn about their ecology and *** the Yungas ecoregion of Northwestern Argentina,cold-and warm-adapted species of the orders Ephemeroptera,Plecoptera,and Trichoptera(EPT)are segregated by *** modeled the ecological niche of South American EPT species in this region using available data and projected their potential distribution in geographic *** were grouped based on their ecogeographic similarity,and we analyzed their replacement pattern along elevation gradients,focusing on the ecotone where opposing thermal preferences *** this interface,we identified critical points where the combined incidence of cold and warm assemblages maximizes,indicating a significant transition *** found that the Montane Cloud Forest holds the interface,with a particularly greater suitability at its lower *** main axis of the interface runs in a N-S direction and falls between 14°C-16°C mean annual *** probability of a particular location within a basin being classified as part of the interface increases as Kira’s warmth index approaches a score around *** the interface is critical for defining the thermal limits of species distribution and designing biomonitoring *** in the location of thermal constants related to mountainous ecotones may cause vertical displacement of aquatic insects and vegetation *** have recognized significant temperature thresholds that serve as indicators of suitability for the *** global warming is anticipated to shift these indicators,we suggest using them to monitor the imprints of climate change on mountain ecosystems.

关键词： Austral Yungas Ecological Niche Model Ephemeroptera Kira’s warmth index Plecoptera Trichoptera

Time-frequency multiresolution of fault-generated transient signals in transmission lines using a morphological filter

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Protection and Control of Modern Power Systems 2023年第2期8卷 85-98页

作者： Juan Carlos Quispe John Morales Eduardo Orduna Carlo Liebermann Michael Bruhns Peter Schegner Universidad Nacional de San Juan-conicet San JuanArgentina Universidad Tecnológica del Perú LimaPerú Technical University of Dresden DresdenGermany

The ongoing transformation of electrical power systems highlights the weaknesses of the protection schemes of traditional devices because they are designed and configured according to traditional characteristics of the ***,this work proposes a new methodology to study the fault-generated high frequency transient signals in transmission lines through multiresolution *** high frequency components are determined by a new digital filtering technique based on mathematical morphology theory and a spectral energy ***,wide spectra of signals in the time–frequency domain are *** performance of this method is verified on an electrical power system modeled in ATP-Draw,where simulation and test signals are developed for different locations,fault resistances,inception angles,high frequency noises,sampling frequencies,types of faults,and shapes of the structuring *** results show the characteristics of the fault such as the traveling wave frequency,location,and starting time.

关键词： Digital filter High frequency Mathematical morphology Time–frequency Traveling waves