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Gastropods Associated with Fossil Traces from Yacoraite Formation(Maastrichtian-Danian),and its Paleoenvironmental Significance,Jujuy,Northwestern argentina

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Acta Geologica Sinica(English Edition) 2009年第5期83卷 860-867页

作者： Carlos A.CóNSOLE GONELla Miguel GRIFFIN Florencio G.ACENOlaZA Instituto Superior de Correlacion Geologica(INSUGEO-CONICET) TucumanArgentina Division Paleozoologia de Invertebrados Facultad de Ciencias Naturales y MuseoUniversidad Nacional de la Plata(UNLP-CONICET)Buenos AiresArgentina

We present results tending to characterize the new records of invertebrates from the Yacoraite Formation （Maastrichtian-Danian）. The fossils reported come from two stratigraphic sections exposed in the surroundings of Maimara and Jueya, province of Jujuy, northwestern argentina. The selection was based on geological and paleontological evidence. The recovered fossils include gastropods and invertebrate fossil traces, including Planolites, Skolithos and Gastrochanoelites ichnogenus. As result of our review, we discussed the possibility of assigning the analyzed gastropods to the family Zygopleuridae （gene. et. sp. indet.）, as an approximation to the taxonomic resolution of this fossil fauna. The trace fossils were assigned to the archetypical Glossifungites ichnofacies. The study of the fossil assemblage allowed us to define a shallow depositional environment, characteristic of a marine context with high-energy conditions.

关键词： gastropod Glossifungites Yacoraite Formation

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

Human umbilical artery smooth muscle exhibits a 2-APBsensitive capacitative contractile response evoked by vasoactive substances and expresses mRNAs for STIM, Orai and TRPC channels

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BIOCELL 2012年第2期36卷 73-81页

作者： ANA ROCÍO ROLDÁN PALOMO PEDRO MARTIN ALEJANDRO REBOLLEDO NICOLÁS ENRIQUE LUIS E.FLORES VERÓNICA MILESI GINFIV–Grupo de Investigación en Fisiología Vascular Facultad de Ciencias ExactasUniversidad Nacional de La Plata.Argentina CENEXA–Centro de Endocrinología Experimental y Aplicada (UNLP-CONICET La PlataCentro Colaborador OPS/OMS)Facultad de Ciencias MédicasUniversidad Nacional de La Plata.Argentina

After depletion of intracellular Ca^(2+)stores the capacitative response triggers an extracellular Ca^(2+)influx through store-operated channels(SOCs)which refills these *** objective was to explore if human umbilical artery smooth muscle presented this response and if it was involved in the mechanism of serotonin-and histamine-induced *** Ca^(2+)depletion by a Ca^(2+)-free extracellular solution followed by Ca^(2+)readdition produced a contraction in artery rings which was inhibited by the blocker of Orai and TRPC channels 2-aminoethoxydiphenyl borate(2-APB),suggesting a capacitative *** presence of 2-APB the magnitude of a second paired contraction by serotonin or histamine was significantly less than a first one,likely because 2-APB inhibited store refilling by capacitative Ca^(2+)entry.2-APB inhibition of sarcoplasmic reticulum Ca^(2+)release was excluded because this blocker did not affect serotonin force development in a Ca^(2+)-free *** PCR technique showed the presence of mRNAs for STIM proteins(1 and 2),for Orai proteins(1,2 and 3)and for TRPC channels(subtypes 1,3,4 and 6)in the smooth muscle of the human umbilical ***,this artery presents a capacitative contractile response triggered by stimulation with physiological vasoconstrictors and expresses mRNAs for proteins and channels previously identified as SOCs.

关键词： human umbilical artery capacitative response TRPC channels serotonin histamine

Extraterrestrial microspherules from Bajada del Diablo,Chubut,argentina

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Geoscience Frontiers 2017年第1期8卷 137-149页

作者： M.J.Orgeira L.N.Castro G.A.Goldmann C.B.Prezzi E.Sileo D.R.Vega C.Franzosi R.D.Acevedo O.Martinez J.Rabassa J.F.Ponce O.R.Tofalo departamento de Ciencias Geologicas-lGEBA Facultaci de Ciencias Exactas y NaturalesOniversidad de Buenos AiresCiudad UniversitariaPabelldn 11C1428EHABuenos AiresArgentina Consejo Nacional de lnvestigaciones Cientificas y Tecnicas de argentina CONICEE Argentina departamento de lngenierfa Agrfcola y Uso de la Tierra Facultad de AgronomiaUniversidad de Buenos AiresAv.San Martin 4453CI417DSEBuenos AiresArgentina INQUIMAE Departamento de Qufmica Inorganica.Analitica y Quimica Fisica.Facultad de Ciencias Exactas y Naturales.Universidad de Buenos AiresPabellon IICiudad Universitaria.C1428EHABuenos Aires.Argentina Gerencia de lnvestigacion y Aplicaciones Comision Nacional de Energfa AtomicaUniversidad Nacional General San MartinBuenos AiresArgentina Centro Austral de lnvestigaciones Cientificas CADIC-ConicetUshuaiaArgentina universidad Nacional de la Patagonia"San Juan Bosco"Sede Esquel ChubutArgentina universidad Nacional de la Patagonia"San Juan Bosco"Sede Ushuaia UshuaiaArgentina

The Quaternary infilling of a circular structure located in Bajada del Diablo,Chubut Province,argentina has been proposed as a crater strewn field in previous *** we report the finding of about 65 microspherules collected in a trench excavated in the center of the *** majority of handpicked specimens are single,but some of them exhibit compound *** single specimens are spherical with a mean size of 137 nm,whereas the more complex samples show peduncles and drop *** crystal growth is recognized in the internal structure of some broken *** chemical composition from the surface and center of microspherules was determined by energy dispersive spectrometry employing *** EMPA and XRD analysis indicate that the microspherules are mainly composed of Fe and O with magnetite,Fe0with subordinate *** consideration of possible anthropogenic and volcanic origins,these spherulites are ascribed to an extraterrestrial *** accumulation rate of 47 microspherules per m2/yr is estimated for the studied *** value is two orders of magnitude higher than the reference flux for cosmic dust estimated for the last 1 Ma in the Transantarctic *** microspherules might have been generated as a byproduct of asteroid entry in the atmosphere.

关键词： Extraterrestrial microspherules Chemistry Bajada del Diablo Chubut Patagonia-argentina

Male age and strain affect ejaculate quality in the Mexican fruit fly

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Insect Science 2018年第4期25卷 703-711页

作者： Mariana Herrera-Cruz Solana Abraham Nicolas NuSez-Beverido Norma Flores-Estevez Martha Reyes-Hernandez Mayvi Alvarado Diana P6rez-Staples Catedra CONACYT- Facultad de Medicina y Cirugia Universidad Autonoma 'Benito Juarez' de Oaxaca Oaxaca Mexico laboratorio de Investigaciones Ecoetologicas de Moscas de la Fruta y sus Enemigos Naturales (LIEMEN) PROIMI Tucuman Argentina CONICET Argentina INBIO TECA Universidad Veracruzana Xalapa Veracruz Mexico Instituto de Neuroetologia Universidad Veracruzana Xalapa Veracruz Mexico

Aging in all organisms is inevitable. Male age can have profound effects on mating success and female reproduction, yet relatively little is known on the effects of male age on different components of the ejaculate. Furthermore, in mass-reared insects used for the Sterile Insect Technique, there are often behavioral differences between mass-reared and wild males, while differences in the ejaculate have been less studied. The ejaculate in insects is composed mainly of sperm and accessory gland proteins. Here, we studied how male age and strain affected （i） protein quantity of testes and accessory glands, （ii） the biological activity of accessory gland products injected into females, （iii） sperm viability, and （iv） sperm quantity stored by females in wild and mass-reared Anastrepha ludens （Diptera： Tephritidae）. We found lower protein content in testes of old wild males and lower sperm viability in females mated with old wild males. Females stored more sperm when mated to young wild males than with young mass-reared males. Accessory gland injections of old or young males did not inhibit female remating. Knowledge of how male age affects different ejaculate components will aid our understanding on investment of the ejaculate and possible postcopulatory consequences on female behavior.

关键词： accessory glands age Anastrepha ludens mass-rearing sperm Tephritidae

The best of both worlds:mastering nerve regeneration combining biological and nanotechnological tools

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Neural Regeneration Research 2023年第3期18卷 556-557页

作者： Paula A.Soto Marcela B.Fernández van Raap C.Patricia Setton-Avruj departamento de Química Biológica Cátedra de Química Biológica PatológicaUniversidad de Buenos AiresFacultad de Farmacia y BioquímicaInstituto de Química y Fisicoquímica Biológicas(IQUIFIB)Universidad de Buenos AiresBuenos AiresArgentina departamento de Física Universidad Nacional de La Plata(UNLP)Facultad de Ciencias ExactasLa PlataArgentinaLaboratorio de BiotecnologíaUniversidad ORT UruguayMontevideoUruguay

Over the last decade,remarkable developments in nanotechnology have powered medical research,unveiling new approaches for the solution of public health issues such as the treatment of traumatic peripheral neuropathies.

关键词： traumatic technological treatment

OSCILlaTION AND VARIATION OF THE laGUERRE HEAT AND POISSON SEMIGROUPS AND RIESZ TRANSFORMS

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Acta Mathematica Scientia 2012年第3期32卷 907-928页

作者： J.J.Betancor R.Crescimbeni J.L.Torrea departamento de An'aisis Matema'ico Universidad de La Laguna38271-La LagunaTenerifeIslas CanariasSpain departamento de Matema'ica Universidad Nacional del ComahueBuenos Aires 14008300 Neuqu'enArgentina departamento de Matem'aticas Facultad de CienciasUniversidad Auto'noma de Madrid28049 MadridSpain

In this article, we study LP-boundedness properties of the oscillation and vari- ation operators for the heat and Poissson semigroup and Riesz transforms in the laguerre settings. Also, we characterize Hardy spaces as... 详细信息

关键词： Oscillation variation heat laguerre semigroup Riesz transforms

The Rhyacian El Cortijo suture zone: Aeromagnetic signature and insights for the geodynamic evolution of the southwestern Rio de la Plata craton, argentina

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Geoscience Frontiers 2014年第1期5卷 43-52页

作者： Carlos J.Chernicoff Eduardo O.Zappettini Javier Peroni Council for Scientifc and Technical Research (CONICET) Argentina Argentine Geological-Mining Survey (SEGEMAR) Argentina

The amalgamation of the southern Rio de la Plata craton involves two possibly coeval Rhyacian sutures associated with the Transamazonian orogeny, rather than a single one as previously envisaged, i.e. the El Cortijo suture zone and the Salado suture. We circumscribe the Tandilia terrane to the region between these two sutures. The E1 Cortijo suture zone runs along a roughly WNW oriented magnetic low aligned along the southern boundary of the Tandilia terrane, i.e. boundary between the Tandilia and Balcarce terranes. This extensive magnetic low, ca. 300 km long, and ca. 90 km wide, would be caused by demagnetization associated with shearing. At a more local scale, the trend of the El Cortijo suture zone often turns toward the E-W. At this scale, WNW trending tholeiitic dykes of Statherian age are seen to cut the Rhyacian E1 Cortijo suture zone. Spatially associated with the El Corti]o suture zone, there are small magnetic highs interpreted to be related to unexposed basic bodies of ophiolitic nature related to those forming part of the El Cortijo Formation. We envisage the pre-Neoproterozoic evolution of the Tandilia belt to have been initiated by the extension of Neoarchean （ - 2650 Ma） crust occurred during Siderian times （2500-2300 Ma）, causing the separation between the Balcarce, Tandilia and Buenos Aires terranes, and the development of narrow oceans at both north and south sides of the Tandilia terrane, accompanied by -2300-2200 Ma sedi- mentation over transitional -continental to oceanic- crust, and arc magmatism developed in the Tan- dilia terrane. The island arc represented by the El Cortijo Formation was also developed at this time. At late Rhyacian times, it occurred in both the closure of the narrow oceans developed previously, the entrapment of the El Cortijo island arc, as well as anatectic magmatism in the Balcarce terrane.

关键词： El Cortijo suture zone Rhyacian Rio de la Plata craton Aeromagnetics

Indentation Size Effect inβCuAlBe and Cu-2Be Alloys

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Acta Metallurgica Sinica(English Letters) 2021年第12期34卷 1669-1678页

作者： Susana Montecinos Sebastian Tognana Walter Salgueiro IFIMAT Facultad de Ciencias ExactasUniversidad Nacional del Centro de La Provincia de Buenos AiresPinto 3997000 TandilArgentina Consejo Nacional de Investigaciones Científicas y Técnicas CONICET Av.Rivadavia 1917C1033AAJ Buenos AiresArgentina CIFICEN(UNCPBA-CICPBA-CONICET) Pinto 3997000 TandilArgentina Comisión de Investigaciones Científicas de la Provincia de Bs.As Calle 526 entre 10 y 111900 La PlataArgentina

The indentation size effect(ISE)was studied by instrumented nanoindentation and Vickers hardness measurements on polycrystalline copper,βCuAlBe pseudoelastic and age-hardenable CuBe *** in the load-depth curves at different loads would suggest a change in the behavior of the materials as the load *** was estimated at different loads taking into account the pile-up in each case,which was estimated from the images of the topography obtained by atomic force microscopy(AFM).The effect of the microstructure of Cu-2Be(wt%)samples on the ISE was also *** each copper alloy,the Nix and Gao model was applied to the hardness-depth curves,and significant differences were found for the parameters *** is in the constant nanohardness regime for depths below 500 nm,while microhardness exhibits the ISE *** behavior of the nanohardness and the plastic strain with the depth is almost *** presents the lowest values of plastic strains due to the pseudoelastic effect,while Cu presents an almost constant value around 8%,which corresponds to the highest plastic strain obtained.

关键词： Hardness Pseudoelasticity Copper alloys Plasticity Indentation size effect