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Asiatic Callosciurus squirrels as seed dispersers of exotic plants in the Pampas

Current Zoology 2016年第3期62卷 215-219页

作者： S. Yasmin BOBADILLA Veronica V, BENITEZ M. Laura GUICHON Ecologia de Mamiferos Introducidos Departamento de Ciencias Basicas Instituto de Ecologia y Desarrollo Sustentable (INEDES) Universidad Nacional de Lujan Ruta 5 y 7 Lujan (6700) Buenos Aires Argentina

Seed dispersal by exotic mammals exemplifies mutualistic interactions that can modify the habitat by facilitating the establishment of certain species. We examined the potential for endozoochoric dispersal of exotic plants by Callosciurus erythraeus introduced in the Pampas Region of Argentina. We identified and characterized entire and damaged seeds found in squirrel faeces and evaluated the germination capacity and viability of entire seeds in laboratory assays. We collected 120 samples of squirrel faeces that contained 883 pellets in seasonal surveys conducted between July 2011 and June 2012 at 3 study sites within the main invasion focus of C. erythraeus in Argentina. We found 226 entire seeds in 21% of the samples belonging to 4 species of exotic trees and shrubs. Germination in laboratory assays was recorded for Morus alba and Casuarina sp.; however, germination percentage and rate was higher for seeds obtained from the fruits than for seeds obtained from the faeces. The largest size of entire seeds found in the faeces was 4.2 ~ 4.0 ram, whereas the damaged seeds had at least 1 dimension ≥ 4.7 ram. Our results indi- cated that C. erythraeus can disperse viable seeds of at least 2 species of exotic trees. C. erythraeus predated seeds of other naturalized species in the region. The morphometric description suggested a restriction on the maximum size for the passage of entire seeds through the digestive tract of squirrels, which provides useful information to predict its role as a potential disperser or predator of other species in other invaded communities.

关键词： Argentina Callosciurus erythraeus endozoochory invasive species mutualism.

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Nano-synthesis and nano-mechanics of diamond composites and its petroleum drilling applications

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化工新型材料 2010年第S1期38卷 18-18页

作者： Alan J. Hurd LANSCE-lujan Center Los Alamos National Laboratory

We perform synthesis, characterization, and application of nanostructured diamond composites. The enhancements of the thermomechanical performance of bulk diamond compacts in terms of hardness, fracture toughness, wear resistance, impact strength, and thermal stability are our project objectives. It is to aim at applying an advanced nanosynthesis process for the manufac-turing of superhard and ultratough diamond/SiC nanocomposites with the implementation of nanofiber reinforcement. The R&D re-sults can be used in multi-industrial applications, particularly, for drill bits designed to encounter dynamic impacts for high speed oil/gas drillings, thus to achieve high efficiency and energy saving. Science and technology (S&T) researches on precursors, cata-lyst, reactive sintering, and in-situ/real-time characterization of high P-T neutron/X-ray diffraction studies on phase stability, syn-thesis kinetics, residual strain, and yield strength have been applied to help optimizing the nanomanufacturing process. Our R&D ef-fort in high P-T nanosynthesis of TSP diamond/SiC composites is to achieve superior performance of nanomechanics in resisting dy-namic impact and thermal degradation, while still maintaining the super-hardness and super-abrasiveness of diamond and silicon-car-bide. The improved polycrystalline diamond compact (PDC) bit inserts for drilling, boring, and cutting will be applied in harsh envi-ronments so as to meet the demands of the mining, petroleum, and machinery industries. With success of the proposed project, the expected energy savings and reduction of CO2 emission will be significant and the economic advantages are going to be enormous.

关键词： Nano-synthesis and nano-mechanics of diamond composites and its petroleum drilling applications

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Temperature effect on the sensitivity of the copepod Eucyclops serrulatus （Crustacea, Copepoda, Cyclopoida） to agricultural pollutants in the hyporheic zone

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Current Zoology 2015年第4期61卷 629-640页

作者： Tiziana DI LORENZO Walter D. DI MARZIO Marco CIFONI Barbara FIASCA M. BARATTI Maria E. SAENZ Diana M.P. GALASSI Institute of Ecosystem Study - CNR - National Research Council of Italy Via Madonna del Piano 10 50019 Sesto Fiorentino Florence Italy Programa de Investigacion en Ecotoxicologia Departamento de Ciencias Basicas Universidad Nacional de Lujan - Comision National de Investigaciones Cientificas y Tecnicas CONICET Argentina Department of Life Health and Environmental Sciences University of L'Aquila Via Vetoio 1 Coppito 67100 L'Aquila Italy

The sensitivity of freshwater invertebrates to agricultural pollutants is supposed to increase with rising temperature due to global warming. The aim of this study was to measure the effect of temperature on the lethal toxicity of ammonia-N, the herbicide Imazamox and the mixture of the two chemicals, in the adults and the juveniles of a population of the copepod Eucyc- lops serrulatus. This is a widely distributed species found in surface waters, in transitional habitats between surface water and groundwater, and in genuine groundwater environments. We tested the sensitivity by short-term bioassays （96 h） at 15℃ and 18℃, respectively. Our results highlighted the following：（1） increasing temperature affected the sensitivity of the adults to am- monia-N and of the juveniles to the mixture, all of which were more sensitive to its detrimental effects at 18~C; （2） the juvenile stages were more sensitive than the adults to all toxicants, and （3） for all combinations of chemicals and temperatures, the effects were synergistic and approximately one order of magnitude greater than those expected according to a concentration addition model when comparing the LC50 for each chemical in the mixture with the LC50s of chemicals individually assayed. Overall, in a context of global change, ammonia-N and mixtures of agricultural pollutants may affect the survival rate of species that spend a part or the whole life-cycle in the hyporheic habitat, with detrimental effects to biodiversity and ecosystem services provided by the hyporheic biota [Current Zoology 61 （4）： 629~540, 2015].

关键词： Hyporheie Global wanning Copepods Ammonia Herbicide Mixtures

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Neutron scattering and computational studies of the structure and dynamics of NaMgH3

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材料科学与工程（中英文版） 2009年第10期3卷 35-46,75页

作者： Ashley C. Stowe Ragaiy Zidan Alice I. Acatrinei Monika A. Hartl Luke L. Daemen Energy Security Directorate Savannah River National Laboratory Aiken SC 29808 USA Manuel lujan Jr. Neutron Scattering Center Los Alamos National Laboratory Los Alamos NM87545 USA

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Mn＋1AXn Phonon Density of States： Ti3AlC2 and Ti3SiC2 Simulation and Experimentation Results

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Journal of Chemistry and Chemical Engineering 2015年第4期9卷 253-261页

作者： Veronica Gray Gordon J Kearley Oliver Kirstein Ramzi Kutteh Erich H Kisi Daniel P. Riley Frans Trouw School of Engineering University of Newcastle Callaghan NSW 2308 Australia Bragg Institute Australian Nuclear Science & Technology Organisation Lucas Heights NEW 2234 Australia European Spallation Source ESS AB Lund 22100 Sweden School of Physics University of Sydney Sydney NEW2006 Australia Institute of Materials Engineering Australian Nuclear Science & Technology Organisation Lucas Heights NEW2234 Australia lujan centre Los Alamos Neutron Science Center Los Alamos National Laboratory Los Alamos NM 87545 USA

For the first time detailed measurements of the DOS （density of states） for Ti3AIC2 and Ti3SiC2 are presented at temperatures between T = 10 and 100 K. For Ti3AIC2 a DFT （density functional theory） simulation of lattice dynamics is compared to experimental data demonstrating a noticeable difference between the spectra especially below 40 meV. In the case of Ti3SiC2 the DFT model is augmented with MD （molecular dynamics） simulations resulting in the measured and simulated spectra resembling one another more closely but still having significant differences below 40 meV. Within the experimental spectra, there are features up to and including 20 meV which are unaccounted for by the simulation. Tracing individual atoms generated by the computer models suggests anharmonic motion of Si within the Ti3SiC2. The results presented could explain differences between calculated elastic moduli using DFT harmonic lattice dynamics simulations and results from recent experiments.

关键词： Anharmonic anisotropic lattice dynamics Mn+1AXn phase ceramics ab initio molecular dynamics.

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Effect of Aspergillus niger prolyl endopeptidase in patients with celiac disease on a long-term gluten-free diet

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World Journal of Gastroenterology 2024年第11期30卷 1545-1555页

作者： Juan Pablo Stefanolo Verónica Segura Martina Grizzuti Abel Heredia Isabel Comino Ana Florencia Costa Roberto Puebla María Paz Temprano Sonia Isabel Niveloni Gabriel de Diego María E Oregui Edgardo Gustavo Smecuol Mauricio C de Marzi Elena F Verdú Carolina Sousa Julio César Bai Small Bowel Section Department of MedicineGastroenterology Hospital of Buenos Aires“Dr.C.Bonorino Udaondo”Buenos Aires 1264Argentina Department of Microbiology and Parasitology Faculty of PharmacyUniversity of SevilleSeville 41080Spain Department of Medicine Dr.C.Bonorino Udaondo Gastroenterology HospitalBuenos Aires 1264Argentina Basic and Applied Research Group in Immunology and Bioactives(GIBAIB) Institute of Ecology and Sustainable Development(INEDES)National University of LujanLuján 6700Buenos AiresArgentina Department of Medicine Farncombe Family Digestive Health Research InstituteMcMaster UniversityHamilton L8S 4L8OntarioCanada Facultad de Medicina Universidad del SalvadorBuenos Aires C1051ABBArgentina

BACKGROUND The gluten-free diet(GFD)has limitations,and there is intense research in the development of adjuvant *** To examine the effects of orally administered Aspergillus niger prolyl endopeptidase protease(AN-PEP)on inadvertent gluten exposure and symptom prevention in adult celiac disease(CeD)patients following their usual *** This was an exploratory,double-blind,randomized,placebo-controlled trial that enrolled CeD patients on a long-term *** a 4-wk run-in period,patients were randomized to 4 wk of two AN-PEP capsules(GliadinX;AVI Research,LLC,United States)at each of three meals per day or *** endpoints were:(1)Average weekly stool gluten immunogenic peptides(GIP)between the run-in and end of treatments and between AN-PEP and placebo;(2)celiac symptom index(CSI);(3)CeD-specific serology;and(4)quality of *** samples were collected for GIP testing by ELISA every Tuesday and Friday during run-ins and *** Forty patients were randomized for the intention-to-treat analysis,and three were excluded from the per-protocol ***,628/640(98.1%)stool samples were *** was undetectable(0.32μg/g)to potentially cause mucosal *** GIP concentration in the AN-PEP arm was 44.7%lower than in the run-in ***-third of patients exhibiting GIP>0.08μg/g during run-in had lower or undetectable GIP after AN-PEP *** with the run-in period,the proportion of symptomatic patients(CSI>38)in the AN-PEP arm was significantly lower(P<0.03).AN-PEP did not result in changes in specific *** This exploratory study conducted in a real-life setting revealed high adherence to the *** AN-PEP treatment did not significantly reduce the overall GIP stool ***,given the observation of a significantly lower prevale

关键词： Celiac disease Aspergillus niger prolyl endoprotease Gluten immunogenic peptides Trial Symptoms Real-life trial

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