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Bioerosion on Late Pleistocene Marine Mollusks:A Paleoclimatological and Paleoecological Comparison of MIS 7 and MIS 5e with Modern Beaches(Río Negro,Argentina)

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Acta Geologica Sinica(English Edition) 2022年第4期96卷 1181-1198页

作者： Melisa P.CHARO Gisela D.CHARÓ guillermo ACEÑOLAZA Jose L.CAVALLOTTO Instituto Superior de Correlación Geológica(INSUGEO/CONICET-UNT)Miguel Lillo 205 4000 TucumánArgentina Laboratorio de Fluidodinámica Departamento de Ingeniería MecánicaFacultad de IngenieríaUniversidad de Buenos AiresPaseo Colón 850C1063ACVCiudad Autónoma de Buenos AiresArgentina Servicio de Hidrografía Naval Av.Montes de Oca 2124C1270ABW Buenos AiresArgentina

The Late Pleistocene littoral ridges of southern South America,especially those of the north of Argentinean Patagonia,contain remains of mollusk shells with bioerosion *** sites from marine isotope stages(2 from MIS 7,4 from MIS 5 e)and five sites from modern beaches from northern Río Negro Province,with 40 taxa(17 bivalves and 23 gastropods)were analyzed,in the area between west of Baliza San Matías and Las Grutas(41°S).Three ichnogenera were identified in deposits of MIS 7:Entobia,Gastrochaenolites(Domichnia)and Oichnus(Praedichnia)with one ichnospecies(***).Six ichnogenera were identified in deposits of MIS 5 e:Entobia,Meandropolydora,Pinaceocladichnus,Iramena,Caulostrepsis and Oichnus with one ichnospecies(***).Seven ichnogenera were identified from modern beaches:Entobia,Meandropolydora,Iramena,Caulostrepsis,Pinaceocladichnus,Gastrochaenolites(Domichnia)and Oichnus(Praedicnia),with two ichnospecies(*** and ***).On this basis,it is inferred that Pleistocene benthic communities were constituted from cheilostome bryzoans and polychaete annelids,together with drilling bivalves,predatory gastropods and overall warm-water species of *** these,Chama iudicai was found on Plicatula gibbosa from MIS 7 and MIS 5 *** record of warm temperature species suggests a higher sea surface temperature(SST)than the present one and/or the influence of the warm southward Brazilian Current affecting the waters of Golfo San Matí*** the modern beaches surveyed,there is an increase in polychaete annelids,cheilostome bryzoans,temperate-cold species and drilling bivalves,as well as sandy substrate species,which together with an increase of Gastrochaenolites and Caulostrepsis,suggest a colder climate due to the greater influence of the Malvinas Current during the Holocene.

关键词： invertebrate paleontology ichnology Bivalvia Gastropoda Polyplacophora bioerosion paleoclimatology paleoecology Quaternary/Holocene Argentina

Site index for teak in Colombia

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Journal of Forestry Research 2012年第3期23卷 405-411页

作者： Danny A.Torres Jorge I.del Valle guillermo Restrepo Office National de Forêts International 2av.de Saint-Mandé75570 Paris Cedex 12France Universidad Nacional de Colombia sede Medellín Apartado Aéreo 568MedellínColombia Independent consultant

Determination of site quality is a basic tool for proper selection of locations and species, in management of forest plantations. Throughout the Caribbean studies of site quality are few and are hampered by statistical limitations, inappropriate growth models, and limited data. We fitted growth curves for dominant height to evaluate and clas- sify site quality ofteak （Tectona grandis） plantations by using data from 44 permanent sample plots established since 1990 in 3--22 years old teak plantations in the Colombian Caribbean region. We used Korf＇s and yon Bertalanffy＇s models to fit curves as non-linear effects models. Both models, with a single random parameter, were considered as adequate for dominant height growth modelling, but Korf＇s model was superior. The resulting curves were anamorphic and closely reflected high variability in site quality. Five site classes were clarified： at a base age of 12 years old, teak reached a mean dominant height of 24.8 m on the best sites, 9.8 m in the worst sites, and in the averages sites, 15.8-18.8 m. Using this model, we identified the best and the worst sites for teak plantations in the Caribbean region. This model proved a useful tool, not only for site quality evaluation, but also for improved teak plantation planning and management.

关键词： Tectona grandis site index growth modelling permanentsample plots Colombia

Analysis of Operating Variables in the Catalytic Purification of Butene-1 in a Trickle Bed

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Chinese Journal of Chemical Engineering 1998年第2期6卷 13-25页

作者： Sergio P.Bressa Néstor O.Ardiaca Osvaldo M.Martinez guillermo F.Barreto Depto.de Ing.Qca. Fac.de Ing.U.N.L.P.l esq.47(1900)La Plata-Argentina Centro de Investigacion y Dcysarrollo en Procesos Cataliticos(CINDECA)Calle 47 N°257CC59(1900)Plata-ArgentinaDepto.de Ing.Qca.Fac.de Ing.U.N.L.P.l esq.47(1900)La Plata-Argentina Centro de Investigacion y Dcysarrollo en Procesos Cataliticos(CINDECA)Calle 47 N°257CC59(1900)Plata-ArgentinaDepto.de Ing.Qca.Fac.de Ing.U.N.L.P.l esq.47(1900)La Plata-Argentina Centro de Investigacion y Dcysarrollo en Procesos Cataliticos(CINDECA)Calle 47 N°257CC59(1900)Plata-ArgentinaDepto.de Ing.Qca.Fac.de Ing.U.N.L.P.l esq.47(1900)La Plata-Argentina Centro de Investigacion y Dcysarrollo en Procesos Cataliticos(CINDECA)Calle 47 N°257CC59(1900)Plata-Argentina

A mathematical model for analyzing and simulating selective hydrogenation of butyne-1 and 1,3-bu-tadiene in industrial trickle bed reactors operated to obtain high purity butene-1 is presented in this *** analysis of typical operating conditions,only the relevant phenomena are finally retained in the model *** model is then employed to analyze the effect of operating variables and catalyst selectivity in *** particular,the search for the minimum hydrogen flow rate necessary to fulfil butene-1 purityspecifications is undertaken.

关键词： selective hydrogenation butene-1 1 3-butadiene trickle bed reactor

Mode-localized accelerometer in the nonlinear Duffing regime with 75 ng bias instability and 95 ng/√Hz noise floor

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Microsystems & Nanoengineering 2022年第1期8卷 237-247页

作者： Hemin Zhang Milind Pandit guillermo Sobreviela Madan Parajuli Dongyang Chen Jiangkun Sun Chun Zhao Ashwin A.Seshia The Nanoscience Centre University of CambridgeCambridge CB30FFUK Silicon Microgravity Ltd. Cambridge Innovation ParkCambridge CB259PBUK MOE Key Laboratory of Fundamental Physical Quantities Measurement and Hubei Key Laboratory of Gravitation and Quantum Physics PGMF and School of PhysicsHuazhong University of Science and Technology430074 WuhanChina

Mode-localized sensors have attracted attention because of their high parametric sensitivity and first-order common-mode rejection to temperature *** high-fidelity detection of resonator amplitude is critical to determining the resolution of mode-localized sensors where the measured amplitude ratio in a system of coupled resonators represents the output *** at specific bifurcation points in a nonlinear regime can potentially improve the amplitude bias stability;however,the amplitude ratio scale factor to the input measurand in a nonlinear regime has not been fully *** paper theoretically and experimentally elucidates the operation of mode-localized sensors with respect to stiffness perturbations(or an external acceleration field)in a nonlinear Duffing *** operation of a mode-localized accelerometer is optimized with the benefit of the insights gained from theoretical analysis with operation in the nonlinear regime close to the top critical bifurcation *** phase portraits of the amplitudes of the two resonators under different drive forces are recorded to support the experimentally observed improvements for velocity random *** temperature control to suppress the phase and amplitude variations induced by the temperature drift,1/f noise at the operation frequency is significantly reduced.A prototype accelerometer device demonstrates a noise floor of 95 ng/√Hz and a bias instability of 75 ng,establishing a new benchmark for accelerometers employing vibration mode localization as a sensing paradigm.A mode-localized accelerometer is first employed to record microseismic noise in a university laboratory environment.

关键词： nonlinear bifurcation gained

Modeling of potential habitat suitability of Hippocamelus bisulcus: effectiveness of a protected areas network in Southern Patagonia

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Ecological Processes 2017年第1期6卷 296-309页

作者： Yamina Micaela Rosas Pablo LPeri Alejandro Huertas Herrera Hernán Pastore guillermo Martínez Pastur Laboratorio de Recursos Agroforestales Centro Austral de Investigaciones Científicas(CONICET)Houssay 200Ushuaia 9410Tierra del FuegoArgentina UNPA-INTA-CONICET.CC 332 Río Gallegos 9400Santa CruzArgentina Delegación Regional Patagonia Norte Administración de Parques NacionalesVicealmirante O’Connor 1188San Carlos de Bariloche 8400Río NegroArgentina

Introduction:Huemul(Hippocamelus bisulcus Molina)is the most threatened flag species of Southern Patagonia,where conservation efforts were not effective to avoid the retraction of its distribution *** quality modeling can assist to design better management strategies for regional conservation *** objective was to elaborate one habitat suitability map for huemul,defining the environmental characteristics at landscape level,and determining the distribution of the suitable habitat inside the current natural reserve ***:We used a database of 453 records and explored 40 potential explanatory variables(climate,topographic,and landscape variables including human-related ones)to develop one habitat suitability map using the Environmental Niche Factor Analysis(ENFA)for Santa Cruz province(Argentina).We combined the outputs in a GIS project using different shapes,including the current natural reserve ***:We defined the potential habitat for huemul,where forest edges and ecotone zones(e.g.,mainly alpine environments)were the most important environmental variables,as well as some forest types(e.g.,Nothofagus pumilio).Habitat losses were found in the extreme potential distribution areas(northern and southern areas),probably related to the increasing ranch *** current natural reserve network maintains approximately half of the huemul potential habitat in Santa Cruz province,where National Parks presented the similar conservation importance than the Provincial natural ***:Habitat suitability model for huemul can be used as a decision support system for new management strategies at different landscape levels to improve the current conservation efforts.

关键词： Nothofagus forests ENFA Habitat loss Conservation Species requirements

Optimal diet strategy of a large-bodied psittacine: food resource abundance and nutritional content enable facultative dietary specialization by the Military Macaw

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Avian Research 2019年第4期10卷 469-477页

作者： Sylvia Margarita de la Parra‑Martinez Luis guillermo Munoz‑Lacy Alejandro Salinas‑Melgoza Katherine Renton Departamento de Ciencias Biologicas Centro Universitario de la CostaUniversidad de GuadalajaraAv.Universidad No.203Delegacion IxtapaC.P.48280 Puerto VallartaJaliscoMexico Comision Nacional Para el Conocimiento y Uso para la Biodiversidad Liga Periferico‑Insurgentes Sur 4903Delegacion Tlalpan14010 Mexico CityMexico Facultad de Biologia Universidad Michoacana de San Nicolas de HidalgoCiudad UniversitariaMoreliaMichoacanMexico Estacion de Biologia Chamela Instituto de BiologiaUniversidad Nacional Autonoma de MexicoApartado Postal 21San Patricio‑MelaqueJaliscoMexico

Background:Dietary specialization should arise when there is a relatively high abundance of a particular resource,where animals may select food items to obtain an optimal diet that maximizes energy ***‑bodied psittacines frequently exhibit a narrow dietary niche with specific habitat use,but few studies have determined whether psittacines select food resources,and how this influences habitat ***:We established fruiting phenology transects to evaluate food resource availability for the large‑bodied Military Macaw(Ara militaris)in semi‑deciduous,deciduous,and pine‑oak forest at two sites along the coast of Jalisco,during the dry season when macaws are *** also determined Military Macaw diet by observations of foraging macaws along transect routes,and conducted bromatological analysis of the nutritional content of the most consumed ***:Military Macaws used six plant species as food items during the dry season,and had a narrow dietary niche(Levins’B=0.28),with 56%of foraging macaws consuming the seeds of Hura *** food resources were recorded in pine‑oak forest during the dry season,with food resources and foraging by macaws concentrated in tropical deciduous and semi‑deciduous forest,where *** was the most abundant fruiting tree *** considering the proportional availability of food resources,we determined a broad Hurlbert dietary niche breadth of H=0.67,indicating that Military Macaws consumed food resources according to their ***,the seeds of *** were an important source of protein,carbohydrates,minerals and moisture,and the hard fruitcasing means that these seeds are exclusively available for ***:By concentrating their diet on the most abundant resources,Military Macaws may increase foraging efficiency in the dry *** high nutrient content also means that concentrating the diet on seeds of *** may be an optimal foraging strategy for Military Macaws

关键词： Ara militaris Bromatological analysis Diet composition Food resource selection Fruiting phenology Hura polyandra Psittacidae Tropical dry forest

Asymmetry in genitalia is in sync with lateralized mating behavior but not with the lateralization of other behaviors

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Current Zoology 2020年第1期66卷 71-81页

作者： Julian TORRES-DOWDALL Sina J.ROMETSCH Gaston AGUILERA guillermo GOYENOLA Axel MEYER Department of Biology University of KonstanzKonstanzGermany Zukunftskolleg University of KonstanzKonstanzGermany Hector Fellow Academy KarlsruheGermany Unidad Ejecutora Lillo(CONICET) Fundacion Miguel LilloTucumanArgentina Departamento de Ecologia y Gestion Ambiental Centro Universitario Regional Del EsteUniversidad de la RepublicaUruguay

Asymmetries in bilateral organisms attract a lot of curiosity given that they are conspicuous departures from the *** allow the investigation of the integration at different levels of biological *** we study whether and how behavioral and asymmetrical anatomical traits coevolved and work *** ask if asymmetry is determined locally for each trait or at a whole individual level in a species bearing conspicuous asymmetrical *** genitalia evolved in many species;however,in most cases the direction of asymmetry is ***,it has been rarely determined if there is an association between the direction of asymmetry in genitalia and other *** onesided livebearer fish of the genus Jenynsia(Cyprinodontiformes,Anablepidae),the anal fin of males is modified into a gonopodium,an intromittent organ that serves to inseminate *** gonopodium shows a conspicuous asymmetry,with its tip bending either to the left or the *** surveying 13 natural populations of Jenynsia lineata,we found that both genital morphs are equally common in wild *** a series of experiments in a laboratory population,we discovered asymmetry and lateralization for multiple other traits;yet,the degree of integration varied highly among *** in exploratory behavior in response to different stimuli was not associated with genital ***,the direction of genital asymmetry was positively correlated with sidedness of mating preference and the number of neuromasts in the lateral *** suggests integration of functionally linked asymmetric traits;however,there is no evidence that asymmetry is determined at the whole individual level in our study species.

关键词： antisymmetry behavioral lateralization Jenynsia iineata Jenynsia multidentata phenotypic integration

The value of the World Conferences on Research Integrity:perspectives from Peru

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Forensic Sciences Research 2021年第3期6卷 347-349页

作者： Mariela DejoVásquez Roxana Lescano Juan guillermo PérezCarreño Universidad de Lima LimaPeru Asociación Peruana para el empleo y bienestar de animales en investigación y docencia(ASOPEBAID) LimaPeru Universidad del Rosario BogotáColombia

“The World Conferences on Research Integrity(WCRIs),six to date,were initiated at a time when researchers in various countries were at quite different stages in their thinking about research *** the course of the past decade,the global conferences have reflected and documented significant changes in the way research integrity is viewed and supported”[1].

关键词： quite World initiated

Ecological perspectives on variable retention forestry

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Ecological Processes 2020年第1期9卷 139-144页

作者： guillermo J.Martínez Pastur Ilkka Vanha-Majamaa Jerry F.Franklin Centro Austral de Investigaciones Científicas(CADIC) Consejo Nacional de Investigaciones Científicas y Técnicas(CONICET)Houssay 200(9410)UshuaiaTierra del FuegoArgentina Natural Resources Institute Finland(Luke) Latokartanonkaari 9FI-00790 HelsinkiFinland School of Environmental and Forest Science University of WashingtonSeattleWA 98195USA

Forest management globally affects the ecosystem services,especially those related to ecosystem functioning and biodiversity conservation,by altering forest structure and *** degree of alteration was related to the intensity and type of harvesting;therefore,the major silvicultural challenge is to develop alternatives to mitigate climate change and maintain forest functions and biodiversity while also providing acceptable levels of timber *** retention forestry(VRF)is a highly flexible concept,with continuity of forest cover,structure,function,and species composition,thereby supporting multiple economic,environmental,and cultural *** special issue provides an overview of the concepts and applications related to VRF implementation around the *** shows that VRF has been applied globally for several decades,with varying levels and retention types,depending on local conditions and the economic importance of *** challenges of VRF seem to differ to some extent on different continents,yet the general aims have been accepted in most of the *** has been successful in mitigating many effects of intensive harvesting,though in some forests of the world,the retention levels are too low to maintain acceptable levels of biodiversity and ecosystem *** conclude that an active collaboration between scientists and forest practitioners is needed to realize all of the opportunities provided by VRF in solving global forestry-related issues.

关键词： Sustainable forestry Biodiversity conservation Timber production Aggregated retention Dispersed retention Forest certification Prescribed burning Synergies and trade-offs