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Volatile organic compounds emitted by Megaplatypus mutatus associated fungi: chemical identification and temperature-modulated responses by the ambrosial beetle

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Ecological Processes 2024年第2期13卷 3-15页

作者： esteban D.Ceriani-Nakamurakare Mariel Slodowicz Cecilia Carmarán Paola gonzalez-Audino Instituto de Micología y Botánica (INMi Bo) Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET ) Departamento de Ingeniería Agrícola y Uso de la Tierra Facultad de Agronomía Universidad de Buenos Aires (UBA) Centro de Investigaciones de Plagas e Insecticidas (CIPEIN) Unidad de Investigación y Desarrollo Estratégico Para la Defensa (UNIDEF) Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET ) Departamento de Biodiversidad y Biología Experimental (DBBE) Facultad de Ciencias Exactas y Naturales (FCEy N) Universidad de Buenos Aires (UBA)

Background In ambrosia and bark beetles–fungi interaction, volatile organic compounds(VOCs) play a central role in mediating various aspects of community dynamics of beetles and/or fungi. These functions include facilitating beetle habitat location, mate identification, and fungal partner differentiation. However, the understanding on this context remains limited, especially in the globally distributed subfamily Platypodinae, which comprises predomi-nantly ambrosia beetles. There is a lack of chemical data on ambrosia fungi from native South American species. This study addresses this gap by characterizing VOCs from twelve fungal species associated with Megaplatypus mutatus and assessing species-specific behavioral responses during *** Fungal VOCs were collected by gas chromatography–mass spectrometry combined with solid-phase microextraction and Y-olfactometry assays of males and females were performed at dispersal stage. Statistical analyses involved: non-metric multidimensional scaling multivariate plot and PERMANOVA test, a cluster analysis through unweighted pair group method with Jaccard index, and finally, a chi-square goodness-of-fit test for beetle behavioral *** We identified 72 VOCs from the fungal species isolated from M. mutatus galleries, exocuticle, and gut. The olfactory behavior of M. mutatus demonstrated its capacity to discriminate between volatile profiles, showing a pref-erence for either the fungus or the control source. Our results also enhance the understanding in a chemotaxonomic context and in the behavioral responses of M. mutatus revealing the beetle's remarkable low temperature toler-ance and its capability to maintain mobility and orientation toward volatile sources even after zero-degree Celsius *** This study presents a comprehensive insight into fungal VOC profiles, emphasizing the sources of isola-tion within pest associated fungi, as well as its symbiotic species from the Raffaelea genus. In

关键词： Ambrosia Raffoelea Fusorium Volatiles Platypodinae Megaplatypus Olfactory behavior Chemotaxonomic Freezing condition

Intersections between innate immune response and gastric cancer development

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World Journal of Gastroenterology 2023年第15期29卷 2222-2240页

作者： Franz Villarroel-Espindola Troy Ejsmentewicz Roxana gonzalez-Stegmaier Roddy A Jorquera esteban Salinas Translational Medicine Unit Instituto Oncologico Fundacion Arturo Lopez PerezSantiago 7500000Metropolitan regionChile

Worldwide,gastric cancer(GC)is the fifth most commonly diagnosed *** has a reduced prevalence but has maintained its poor prognosis being the fourth leading cause of deaths related to *** highest mortality rates occur in Asian and Latin American countries,where cases are usually diagnosed at advanced ***,GC is viewed as the consequence of a multifactorial process,involving the virulence of the Helicobacter pylori(***)strains,as well as some environmental factors,dietary habits,and host intrinsic *** tumor microenvironment in GC appears to be chronically inflamed which promotes tumor progression and reduces the therapeutic *** has been suggested that inflammation assessment needs to be measured qualitatively and quantitatively,considering cell-infiltration types,availability of receptors to detect damage and pathogens,and presence or absence of aggressive *** *** epithelial cells express several Toll-like receptors and determine the first defensive line against pathogens,and have been also described as mediators of ***,other molecules,such as cytokines related to inflammation and innate immunity,including immune checkpoint molecules,interferon-gamma pathway and NETosis have been associated with an increased risk of ***,this review will explore innate immune activation in the context of premalignant lesions of the gastric epithelium and established gastric tumors.

关键词： Gastric cancer Toll-like receptor Helicobacter pylori Nuclear factor kappa B Neutrophils

The nature of the frictional force at the macro-, micro-, and nano-scales

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Friction 2014年第1期2卷 40-46页

作者： esteban BROITMAN IFM Linköping UniversitySE 58183Sweden

Nowadays it is accepted that the friction force is a combined effect arising from various phenomena:adhesive forces,capillary forces,contact elasticity,topography,surface chemistry,and generation of a third body,*** of them can dominate depending on the experimental force and length scales of the *** forces in macro-tribology are in the Newtons,while are reduced to milli-/micro-Newtons,and nano-Newtons in micro-and nano-tribology,*** this paper,experimental friction results from fullerene like CNx films and single-crystal Si at the three scales will be *** complex and broad variety of processes and phenomena connected with the dry friction coefficient at the macro-,micro-,and nano-scale point of view will be highlighted.

关键词： macrotribology microtribology nanotribology carbon nitride silicon

Induced pluripotent stem cell (iPS) technology:promises and challenges

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Chinese Science Bulletin 2009年第1期54卷 2-8页

作者： MIGUEL A esteban Laboratory of Regenerative Biology South China Institute for Stem Cell Biology and Regenerative MedicineGuangzhou Institute of Biomedicine and HealthChinese Academy of Sciences

In 2006,an article published in Cell by Shinya Yamanaka took by surprise the stem cell research community. By performing systematic retroviral transduction of factors enriched in embryonic stem (ES) cells,the authors demonstrated the reprogramming of mouse fibroblasts into an ES cell-like state. These cells,baptized iPS (induced pluripotent stem) cells,were immediately recognized as a ground-breaking discovery. Subsequently,the same authors and other groups reported a similar achievement with human fibroblasts. Two years later,the number of top quality papers on iPS is astonishing,and interest in the scientific community has risen to a fever pitch. But although iPS has the potential to revolutionize Regenerative Medicine,important questions still remain unanswered. Work from multiple laboratories worldwide including ours is focused on deciphering the molecular mechanisms of iPS,and trying to improve the technique to make it suitable for the clinic. In this review article we briefly discuss the past,present and future of iPS,with emphasis on urgent issues to be solved.

关键词：自身更新多能性胚胎干细胞多能干细胞

Frozen ground and periglacial processes relationship in temperate high mountains: a case study at Monte Perdido-Tucarroya area(The Pyrenees, Spain)

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Journal of Mountain Science 2020年第5期17卷 1013-1031页

作者： SERRANO Enrique LóPEZ-MORENO Juan Ignacio GóMEZ-LENDE Manuel PISABARRO Alfonso MARTíN-MORENO Raúl RICO Ibai alonso-GONZáLEZ esteban Dept of GeographyUniversity of ValladolidValladolid 47011Spain Dept of Geoenvironmental Processes and Global ChangePyrenean Institute of EcologyZaragoza 50.080Spain Dept.Specific Didactics.Autonom University of Madrid.Madrid 28049Spain Dept of GeographyPrehistory and ArcheologyUniversity of the Basque CountryVitoria 01006Spain

Seasonally frozen ground,mountain permafrost and cryogenic geomorphological processes are important components of the Pyrenean high *** work presents the results of a study on the distribution of frozen ground in a marginal and paraglacial environment of temperate *** inventory was made of landforms and indicators of frozen ground,and frozen ground was mapped *** 2014 and 2016 ground temperatures and thermal regimes were monitored,basal temperatures of snow-cover(BTS)were measured and a thermal map was *** thermal behaviours were detected among different elevations and slope *** processes are the most widespread,in which frost weathering and nivation,together with gelifluction and cryoturbation,are the most efficient processes;the latter two are generally linked to the presence of frozen *** fall in air and ground temperatures with altitude,slope orientations,and snowpack thickness and evolution determine ground thermal *** the study area,three types of thermal regimes were established:climate-controlled,snowcover-controlled,and frozen *** frozen ground occurs across a broad range of elevation between 2650 and 3075 m asl,whereas possible permafrost only occurs above 2750 m asl.

关键词： Geomorphology Periglacial Seasonally frozen ground Mountain permafrost Pyrenees

Short-term effects of post-fire mulching with straw or wood chips on soil properties of semi-arid forests

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Journal of Forestry Research 2023年第6期34卷 1777-1790页

作者： Manuel esteban Lucas Borja Demetrio Antonio Zema Department of Agroforestry Technology Science and GeneticsSchool of Advanced Agricultural and Forestry EngineeringCampus Universitario s/nCastilla La Mancha UniversityE-02071 Castilla La ManchaAlbaceteSpain Department AGRARIA “Mediterranea”University of Reggio CalabriaLocalitàFeo di VitoI-89122 Reggio CalabriaItaly

Few studies have compared the variability of soil properties using different types of mulches in semi-arid *** study evaluated the changes in physico-chemical soil properties in a semi-arid forest of Central Eastern Spain,where straw and pine wood chips were distributed as mulch three months after a *** were sampled under burned and unmulched and burned and mulched plots three and nine months after the *** data was processed using Principal Component Analysis(PCA)and Analytical Hierarchical Cluster Analysis(AHCA).Mulching with straw or wood chips did not have any significant effects on the texture and chemical properties of burned sites few months after the *** contrast,significant changes are expected over time in organic matter,nutrients and many *** were no significant differences in soil properties between the two *** low changes were confirmed by PCA coupled with AHCA,which did not show a clear distinction among the three soil ***,a noticeable and significant variability of many of these properties over time was *** study shows that mulching does not degrade of soil properties in the short-term after a wildfire and after post-fire treatments,and thus helps protect semi-arid forest ecosystems against the negative impacts of high-severity fires.

关键词： Post-fire management High-severity fire Aridisols Erosion Vegetal residues incorporation Soil degradation

Origin of light emission and enhanced Eu^(3+) photoluminescence in tin-containing glass

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Journal of Rare Earths 2015年第1期33卷 27-32页

作者： José A.Jiménez esteban Rosim Fachini Department of Chemistry University of North FloridaJacksonville FL 32224 USA Department of Physical Sciences General Studies Faculty University of Puerto RicoRío Piedras PR 00931 USA

A barium-phosphate glass matrix was co-doped with Sn O and Eu2O3 for investigating on material luminescent properties. Optical absorption and X-ray photoelectron spectroscopy（XPS） were employed in the characterization of tin species. The prevalence of divalent tin was indicated by the XPS data in accord with a conspicuous absorption band detected around 285 nm ascribed to twofold-coordinated Sn centers（isoelectronic with Sn^2＋）. Photoluminescence（PL） excitation spectra obtained by monitoring Eu^3＋ emission from the 5D0 state revealed a broad excitation band from about 250 to 340 nm, characteristic of donor/acceptor energy transfer. Under excitation of such at 290 nm, the co-doped material exhibited a bright whitish luminescence, and a four-fold enhanced Eu3＋ emission relative to a purely Eu-doped reference. Time-resolved PL spectra recorded under the excitation at 290 nm exposed a broad band characteristic of the twofold-coordinated Sn centers and emission bands of Eu^3＋ ions, which appeared well separated in time in accord with their emission decay dynamics. The data suggested that light absorption took place at the Sn centers（donors） followed by energy transfer to Eu^3＋ ions（acceptors） which resulted in populating the 5D0 emitting state. Energy transfer pathways likely resulting in the enhanced Eu3＋ photoluminescence and the consequential light emission were discussed.

关键词： energy transfer glasses luminescence optical materials rare earths

Numerical modeling of cracking pattern's influence on the dynamic response of thickened tailings disposals: a periodic approach

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Earthquake Engineering and Engineering Vibration 2018年第1期17卷 179-190页

作者： Gabriel Ferrer esteban Sáez Christian Ledezma School of Engineering Pontificia Universidad Católica de Chile National Research Center for Integrated Natural Disaster Management

Copper production is an essential component of the Chilean economy. During the extraction process of copper, large quantities of waste materials（tailings） are produced, which are typically stored in large tailing ponds. Thickened Tailings Disposal（TTD） is an alternative to conventional tailings ponds. In TTD, a considerable amount of water is extracted from the tailings before their deposition. Once a thickened tailings layer is deposited, it loses water and it shrinks, forming a relatively regular structure of tailings blocks with vertical cracks in between, which are then filled up with ＂fresh＂ tailings once the new upper layer is deposited. The dynamic response of a representative column of this complex structure made out of tailings blocks with softer material in between was analyzed using a periodic half-space finite element model. The tailings＇ behavior was modeled using an elasto-plastic multi-yielding constitutive model, and Chilean earthquake records were used for the seismic analyses. Special attention was given to the liquefaction potential evaluation of TTD.

关键词： Thickened tailings Liquefaction Periodic modeling

The impact of cultural assumptions on simulated energy, comfort, and investment returns of design decisions in two desert climates

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Building Simulation 2021年第4期14卷 931-944页

作者： esteban Estrella Guillen Holly W.Samuelson Christine Vohringer Harvard Graduate School of Design 48 Quincy St.CambridgeMAUSA Universidad de Monterrey Av.Ignacio Morones Prieto 4500San Pedro Garza GarcíaNLMexico

In Latin America, default assumptions and borrowed templates and methodologies are often used in energy modeling, resulting in models that might not represent their cultural context and leading to policies awkwardly fit to local practices. Policy-driving low-income housing studies in Mexico, for example, activated both heating and cooling in energy models even though less than 5% of the homes in the country have heating systems. This paper illustrates the importance of modeling local sociocultural habits and practices, and how this can affect design outcomes. Here, we modeled low-income housing representative of typical residences in two desert climates-Hermosillo, Mexico, and Copiapo, Chile-using EnergyPlus. Settings representing local practices in each region were tested against default values, including occupancy settings, regional construction systems, and importantly, HVAC settings related to partial conditioning. Their impacts were measured via variation in energy use, comfort conditions, and the payback period of design upgrades. Results demonstrated how certain assumptions can have a high “design significance”, a term we propose for inputs that completely change optimal design decisions, as well as the importance of considering thermal comfort in such decisions. Including partial conditioning, for example, resulted in at least double the payback period and discomfort degrees for design upgrades in 16 of 24 instances.

关键词： performance simulation energy model low-cost housing housing policy thermal comfort culture