Photoisomerization of Azobenzenes and Spirocompounds in Nematic and in Twisted Nematic Liquid Crystals
Bossi, Mariano Luis; Murgida, Daniel Horacio; Aramendia, Pedro Francisco
Samples of a nematic mixture of ZLI1132 and of a twisted nematic mixture composed of ZLI1132 and chiral inductor S811, including 1%-10% (w/w) 4-N,N-dimethylaminoazobenzene (DAB), (4′-nitro)-4-N,Ndimethylaminoazobenzene (NDAB), spiropyran (SP), or spirooxazine (SO) were irradiated to produce the photochromic transformation of the dopant. The changes in the system were monitored by time-resolved transmission spectroscopy, time-resolved birefringence, or polarized Raman scattering. The medium sensitivity of the kinetics and spectroscopy of some of the probes was used to derive information on polarity of the medium. In the systems studied, apart from the changes in absorption spectrum, great changes in birefringence can be photoinduced and the order of the nematic phase can be changed in either direction, depending on the dopant. The open form of SP can discriminate orientation polarity. Although the polarity parallel to the mesogenic director is similar to that for acetone, the perpendicular orientation has a polarity similar to acetonitrile. In agreement with this observation, the kinetics of the Z f E isomerization of NDAB, oriented parallel to the mesogenic director, also experiences a polarity similar to that for acetone. The decay rate constant of the open form of SP displays a linear relationship between its Arrhenius parameters, which is universal in a great variety of homogeneous solvents, solvent mixtures, and liquid crystals, therefore validating the hypothesis that the same type of transformation is observed in all these cases, namely, the decay of the open form monomer. The dopants used have been proven to be adequate probes of bulklike properties in locally heterogeneous systems as liquid crystals.
Sea quark polarization and semi-inclusive DIS data
Jiang, X.; Navarro, Gabriela Alejandra; Sassot, Rodolfo
We investigate the potential impact of forthcoming Jefferson Lab semi-inclusive polarized deep inelastic scattering proton measurements in the determination of the sea quark polarization in the nucleons by means of a next to leading order global QCD analysis. Specifically, we estimate the resulting improvement in the constraints on polarized parton densities for different flavors, which is found to be significant for up and strange quarks, and the correlation between remaining uncertainty ranges for each of the parton species.
Spin-charge separation and topological phase transitions in Aharonov-Bohm rings of interacting electrons
Normand, B.; Hallberg, Karen Astrid; Aligia, Armando Ángel; Kampf, A. P.
We investigate the properties of strongly correlated electronic models on a flux-threaded ring connected to semi-infinite free-electron leads. The interference pattern of such an Aharonov-Bohm ring shows sharp dips at certain flux values, determined by the filling, which are a consequence of spin-charge separation in a nanoscopic system. The conductance through such a molecule or nanodevice is related directly to its spectroscopic properties, opening new experimental possibilities for probing the phenomenology of strongly interacting systems. As a further example, for a ring described by the half-filled ionic Hubbard model we show that the weight of the first conductance peak as a function of gate voltage or external flux allows one to identify the topological charge transition between a correlated insulator and a band insulator.
High level expression of bioactive recombinant human growth hormone in the milk of a cloned transgenic cow
Salamone, Daniel Felipe; Barañao, Jose Lino Salvador; Santos, Claudio; Bussmann, Leonardo Edmundo; Artuso, Jorge; Werning, Carlos; Prync, Aida; Carbonetto, Cesar; Dabsys, Susana; Munar, Carlos; Salaberry R; Berra, Guillermo; Berra, Ignacio; Fernández, Nahuel; Papouchado, Mariana; Foti, Marcelo; Judewicz, Norberto; Mujica, Ignacio; Muñoz, Luciana; Fernandez Alvarez, Silvina; González, Eliseo; Zimmermann, Juan; Criscuolo, Marcelo; Melo, Carlos
Transgenic farm animals have been proposed as an alternative to current bioreactors for large scale production of biopharmaceuticals. However, the efficiency of both methods in the production of the same protein has not yet been established. Here we report the production of recombinant human growth hormone (hGH) in the milk of a cloned transgenic cow at levels of up to 5 g l(-1). The hormone is identical to that currently produced by expression in E. coli. In addition, the hematological and somatometric parameters of the cloned transgenic cow are within the normal range for the breed and it is fertile and capable of producing normal offspring. These results demonstrate that transgenic cattle can be used as a cost-effective alternative for the production of this hormone.
24-hour rhythms of splenic mitogenic responses, lymphocyte subset populations and interferon γ release after calorie restriction or social isolation of rats
Cano, Pilar; Cardinali, Daniel Pedro; Fernández, Pilar; Reyes Toso, Carlos Felipe
To assess the effect of calorie restriction equivalent to a 66% food restriction or social isolation on splenic immune responses, calorie-restricted five week-old male Wistar rats, pair fed controls individually caged and pair fed controls caged in groups, were studied for four weeks. Calorie restricted and isolated rats showed increased splenic concanavalin A response with peak activity during the activity span. Mean 24 h values of splenic lipopolysaccharide response decreased in isolated rats compared to grouped rats. The highest values of T cells occurred in calorie restricted rats and those of B cells in isolated rats. Mean values of splenic CD4+ and CD8+ cells augmented in isolated or calorie restricted groups. The highest in vitro interferon-gamma production occurred in the isolated group and the lowest in the grouped rats, the differences among groups being significant. Both experimental procedures generally disrupted 24-h rhythmicity of splenic immune parameters. Mean values of plasma corticosterone were higher in calorie restricted rats than in isolated rats and both differed significantly from grouped rats. The results indicate that either calorie restriction or social isolation augmented cell-mediated immunity in rat spleen.
PROPAT: A study to improve the quality and reduce the cost of diabetes care
Gagliardino, Juan Jose; Olivera, E.; Etchegoyen, Graciela Susana; Guidi, Mabel Leticia; Caporale, J. E.; Martella, A.; De La Hera, M.; Siri, F.; Bonelli, P.
Objective: In PROPAT we implemented an integrated approach to diabetes care designed to improve the quality and reduce the cost of care. Study design and methods: PROPAT was a case-control study matching patients by age and gender (diabetes:control ratio 1:2) within IOMA, a public employment-based health maintenance organization (HMO) of the Province of Buenos Aires, Argentina. Costs were evaluated using prevalence data from an HMO perspective. We currently report clinical and biochemical data and costs from the first 297 patients enrolled who completed 1 year in PROPAT, and compare them with those derived from control patients. Results: All recommended practices recorded as care provided at baseline increased significantly 1 year after implementing PROPAT, with a parallel significant improvement in several clinical and biochemical parameters, and markedly lower total annual per capita costs. Conclusions: These results demonstrate that the implementation of a comprehensive diabetes care program can simultaneously improve quality while reducing costs.
Preferencia alimentaria de arañas Misumenops pallidus (Araneae: Thomisidae) sobre potenciales insectos presa de cultivos de alfalfa; Feeding preferences of the spider Misumenops pallidus (Araneae: Thomisidae) on potential prey insects from alfalfa crops
Cheli, German Horacio; Armendano, Andrea Viviana; Gonzalez, Alda
Feeding preferences of the spider Misumenops pallidus (Araneae: Thomisidae) on potential prey insects from alfalfa crops. The spider Misumenops pallidus (Thomisidae) is commonly found in alfalfa crops. We studied its predatory preferences on potential insect prey, particularly regarding agroecosystems pests. Two kinds of tests were done under normal laboratory conditions: simultaneous presentation of prey (n= 215) and alternative prey test (n= 45). The spiders preferred insects that were mobile, small, without defensive glands and with thin exoskeletons. According to the amount of prey consumed, we established four predation levels: high (> 55%, on adult Drosophila melanogaster flies); intermediate (30% -55% on the defoliator larvae of Rachiplusia nu and adult heteropterans: Horciasinus argentinus and Halticus spegazzinii); and low (10%- 30% on the chrysomelids Colapsis sp. and Diabrotica speciosa). The pentatomid Piezodorus guildinii, the curculionid Naupactus sp. and the aphid Acyrthosiphom pisum were not accepted as food. Once the spider captured a prey item it did not accept another, independently of prey item species (82% of trials).
A rare endemic land-snail from Argentina: Plagiodontes rocae Doering 1881 (Gastropoda: Orthalicidae: Odontostominae)
Piza, Julia; Ghezzi, Natalia S; Cazzaniga, Néstor Jorge
Plagiodontes rocae Doering 1881 is a strictly endemic species from the Paleozoic mountains of southern Buenos Aires province (Argentina). Its identity has been never controversial, but its description and discrimination from related species was still incomplete. A quantitative analysis of its measurements was advisable to locate the species in the frame of a morphological re-analysis of all species in genus Plagiodontes Doering1876. In this study, Protoconch sculpture is illustrated by SEM micrographs to rectify previous descriptions. Shell measurements and angles are studied by Multivariate Discriminant Analysis to discriminate it from other small-sized species. Genital anatomy of P. rocae is described for the first time, its quantitative data being discriminated by multivariate methods from those of the only co-existing Odontostominae, i.e., Plagiodontes pat-agonicus.; Plagiodontes rocae Doering 1881 ist eine endemische Art des paläozoischen Berglandes im Süden der Provinz Buenos Aires, Argentinien. Ihr Status als eigenständige Art ist nie in Frage gestellt worden, doch ist ihre Beschreibung und Differenzierung von nahestehenden Arten nicht abgeschlossen. Im Rahmen der Revision aller Plagiodontes-Arten, die wir derzeit durchführen, ist daher eine morphometrische Analyse angebracht, um die Art korrekt einzuordnen. Die Skulptur des Embryonalgehäuses wird mittels SEM-Mikrographie dargestellt. Gehäusemaße und -winkel werden mit Hilfe der Multivariaten Diskriminanzanalyse mit denen anderer kleingehäusiger Arten verglichen. Die Genitalanatomie von P. rocae wird hier zum ersten Mal beschrieben; ihre morphometrischen Daten werden mit Hilfe der Multivarianzanalyse mit P. patagonicus, des einzigen sympatrischen Vertreters der Odontostominae, verglichen.
Los cerraminetos verticales en tierra y su eficiencia economico-tecnologico-termico-energetica
Garzon, Beatriz Silvia
Se describe la adecuación bioambiental de las soluciones autóctonas de disposiciones tecnológicas de cerramientos verticales y las características económico-tecnológico-constructivas, consumo energético de producción, y la determinación de la eficiencia ecológica-térmico-energética de las alternativas planteadas(mampostería de adobe y paneles de madera, caña y barro), la verificación según normas de comportamiento térmico y su comparación con relación a los sistemas tecnológicos convencionales con los cuales se resuelven, en la mayoría de los casos, las viviendas de interés social, planteadas para estas comunidades desde otros sectores (oficial, privado, etc.).
Fully differential cross sections for C6+ single ionization of helium: The role of nucleus-nucleus interaction
Ciappina, Marcelo Fabián; Cravero, Walter Ruben
In this work, we present fully differential cross section (FDCS) calculations using distorted wave theories for helium single ionization by 2 MeV amu-1 C6+ ions. We study the influence of internuclear interaction on low-energy electron emission in the scattering plane. It is shown that by incorporating an internuclear effective charge which depends on the collision momentum transfer and taking into account its interplay with passive electron screening we obtain better agreement with experiments in most cases under consideration. Comparisons are made with absolute experimental measurements and with other theories. We found that for ejected-electron momentum similar to transferred momentum, internuclear potential effects have little contribution to FDCSs.
Bacterioterapia con lactobacilos probióticos para la prevención de infecciones urogenitales
Nader, Maria Elena Fatima
Los lactobacilos son los microorganismos predominantes en el tracto gastrointestinal y urogenital del hombre y los animales homeotermos. También se emplean en la elaboración de diferentes alimentos, lo que los categoriza como GRAS (generally regarded as safe). Si bien están disponibles en productos vaginales en el mercado farmacéutico, hay escasas evidencias de su efectividad para la prevención de infecciones urogenitales. Nuestro grupo de trabajo ha aislado lactobacilos vaginales humanos, seleccionando aquellos con propiedades benéficas o probióticas. Se han estudiado las características tecnológicas para obtener el mayor número de microorganismos vivos (biomasa) y las condiciones para la producción óptima de sustancias antagónicas frente a patógenos urogenitales (ácidos orgánicos, peróxido de hidrógeno, bacteriocinas). Se ha demostrado en animales de experimentación (ratones BALB/c hembra endocriados) que la administración intrauretral de lactobacilos no produce efectos adversos ni modificaciones estructurales o ultraestructurales, previniendo eficazmente las infecciones urinarias. Es necesaria la complementación de estos resultados con estudios en pacientes para demostrar la efectividad de la administración intravaginal de los lactobacilos probióticos seleccionados en la recolonización de la microbiota urogenital, la prevención o la terapia de los diferentes síndromes y cuadros clínicos que afectan al tracto, su efecto sobre las embarazadas, etc., que permitan proponer la bacterioterapia con lactobacilos como alternativa válida a la terapia con otras drogas.; Lactobacilli are the predominant microorganisms in the gastrointestinal and urogenital tracts of human beings and homeotermic animals. They are also used for the elaboration of different fermented foods being categorized as GRAS (generally regarded as safe). Even though they are included into different vaginal products in the pharmaceutical market, there are small amount of evidences of their effectivity in the prevention of urogenital infections. Our research group have isolated human vaginal lactobacilli, selecting those with beneficial or probiotic properties. The technological characteristics to obtain the higher number of viable (biomass) microorganisms and the conditions for the optimal production of antagonistic substances against pathogenic microorganisms (organic acid, hydrogen peroxide, bacteriocins) were determined. In experimental animals (inbreed female BALB/c mice) we demonstrated that the intraurethral administration of lactobacilli does not produce adverse effects or structural or ultra structural modifications in the urogenital tract, preventing effectively the urinary tract infections. The complementation of these results with human assays is necessary to demonstrate effectively the intravaginal administration of selected probiotic lactobacilli on the recolonization of the urogenital microbiota, the prevention or therapy of different clinical syndromes, their effect on pregnant women, etc, that will allow the proposal of the bacteriotherapy with lactobacilli as a valid alternative to the other drugs therapies.
Compensatory renal growth protects mice against Shiga toxin 2-induced toxicity
Camerano, Gabriela Veronica; Bustuoabad, Oscar David; Meiss, Roberto Pablo; Gómez, Sonia Alejandra; Fernández, Gabriela Cristina; Isturiz, Martín Amadeo; Palermo, Marina Sandra; Dran, Graciela Isabel
Uninephrectomy (Unx) is followed by the compensatory renal growth (CRG) of the remaining kidney. Previous evidence has shown that during CRG, renal tissue is resistant to a variety of pathologies. We tested the hypothesis that the functional changes that take place during CRG could attenuate Shiga toxin (Stx) toxicity in a mouse model of Stx2-induced hemolytic uremic syndrome (HUS). The participation of nitric oxide (NO) was analyzed. After CRG induction with Unx, mice were exposed to a lethal dose of Stx2, and the degree of renal damage and mortality was measured. Stx2 effects on the growth, renal blood flow (RBF) and NO synthase (NOS) intrarenal expression in the remaining kidney were then studied. The induction of CRG strongly prevented Stx2-mediated mortality and renal damage. Administration of the NOS inhibitor NG-nitro-L-arginine methyl ester (L-NAME) during CRG partially impaired the protection. Both Stx2 and L-NAME interfered with the hypertrophic and hyperplastic responses to Unx, as well as with the increase in RBF. In intact mice, Stx2 decreased renal perfusion, inhibited endothelial NOS basal expression and enhanced inducible NOS expression; all of these effects were attenuated by prior Unx. It is concluded that during CRG mice are highly protected against Stx2 toxicity and lethality. The protective capacity of CRG could be related to the enhancement of renal perfusion and preservation of eNOS renal expression, counterbalancing two major pathogenic mechanisms of Stx2.
Response to Comment on "Cathepsin-L Influences the Expression of Extracellular Matrix in Lymphoid Organs and Plays a Role in the Regulation of Thymic Output and of Peripheral T Cell Number"
Lombardi, Gabriela; Burzyn, Dalia; Mundiñano, Juliana; Berguer, Paula Mercedes; Costa, Hector Luis; Goldman, Alejandra; Piazzon, Margarita Isabel; Nepomnaschy, Irene
In our article published in The Journal of Immunology in June 1, 2005 (1), we reported that lymph nodes from nackt mice (CTSLnkt/CTSLnkt) are hypertrophied, showing a normal absolute number of CD4+ T cells and a marked increase in the number of CD8+ T lymphocytes. Correlatively, extracellular matrix (ECM) components were found to be increased. Contrarily, in nackt thymus, laminin, fibronectin, and collagen I and IV are markedly decreased, with an augmented output of CD8+ cells. We also reported that a mutated form of cathepsin L can be detected in different organs in nackt mice. These results demonstrate that the nackt mutation in the Ctsl gene influences the levels of ECM components in lymphoid organs, the thymic output, and the number of T cells in the periphery, thus broadly affecting the immune system.
Environmental control of phenological development in two Lesquerella species
Windauer, Liliana; Slafer, Gustavo Ariel; Ravetta, Damián Andrés; Benech-Arnold, Roberto Luis
Lesquerella fendleri and Lesquerella mendocina are two species with potential for domestication as crops for semiarid regions. Understanding the environmental influences on development is a critical step for the introduction of a wild species into cultivation. Under controlled conditions these species responded differently to temperature: L. fendleri phenological approach toward flowering responded linearly to temperature, whereas initiation of flowering in L. mendocina was relatively insensitive to temperature. L. fendleri exhibited a quantitative response to supra-optimal temperatures (with rate of development reduced with further increases in temperature) whereas L. mendocina showed a qualitative response, no flower development at supra-optimal temperatures. In this work undertaken in the field we studied phenological development in L. fendleri and L. mendocina as a function of planting date, quantified the time required to reach particular phenological stages under the various thermal environments, and compared these results with those previously obtained with controlled conditions. We also studied the influence of photoperiod on plant phenology in field situations and through experiments done under controlled conditions. Development rate for both species varied with sowing date with plant cycles shorter in spring sown plants, even if measured in thermal time. L. mendocina plants sown in late spring displayed a biennial cycle. These results are consistent with those obtained under controlled conditions. However, cycle shortening in thermal time with delays in sowing date suggested that factors other than temperature also influenced phenology of these two species. Further studies under controlled conditions showed that phenological development of L. fendleri plants was also altered by photoperiod, with plants displaying a typical long-day response. At the highest temperatures used in these studies L. mendocina plants did not respond to photoperiod. The possibility that incident radiation is involved in L. mendocina response to sowing date is discussed.
Oblique projections and frames
Antezana, Jorge Abel; Corach, Gustavo; Ruiz, Mariano Andres; Stojanoff, Demetrio
We characterize those frames on a Hilbert space H which can be represented as the image of an orthonormal basis by an oblique projection defined on an extension K of H. We show that all frames with infinite excess, and frame bounds 1 ≤ A ≤ B,are of this type. This gives a generalization of a result of Han and Larson which only holds for normalized tight frames.
Effects of pH and electrolyte concentration on the binding between a humic acid and an oxazine dye
Zanini, Graciela Pilar; Avena, Marcelo Javier; Fiol, Sarah; Arce, Florencio
The binding between an oxazine dye and a humic acid was studied in aqueous solutions in the pH range 4-10 and in the supporting electrolyte (KCl) range 0.001-0.1 M. A rather simple spectrophotometric method was developed to construct binding isotherms under conditions were traditional centrifugation or filtration methods fail. The use of this method is possible because humic acid molecules have the ability of changing the spectrum of dye molecules, and this ability is used to quantify the isotherms. All binding isotherms have a Langmuirian shape. The amount of bound dye is strongly dependent on the ionic strength and less dependent on the pH of the solution. The binding is rather strong and mainly driven by non-electrostatic forces. Whereas the Langmuir binding constant is independent of the pH and electrolyte concentration, the number of assessable sites in humic acid for binding oxazine increases by increasing pH and decreasing electrolyte concentration. These results can be directly related to the flexibility of humic acid molecules, which can swell at high pH and low ionic strength, increasing consequently the availability of binding sites. The results also indicate that humic substances may strongly affect the mobility and fate of dyes and related pollutants in the environment.
A proposed Global Boundary Stratotype Section and Point for the base of the Middle Ordovician Series: The Niquivil section, Precordillera of San Juan, Argentina
Albanesi, Guillermo Luis; Carrera, Marcelo Gabriel; Cañas, Fernando Luis; Saltzman, Matthew
The Niquivil section, Argentine Precordillera, fulfills most of the requirements for a Global Stratotype Section and Point (GSSP) for the base of the Middle Ordovician Series. It has excellent conodont biostratigraphy in a continuous succession of uniform lithology, is readily accessible, and the critical interval is not tectonically affected. The position of the Lower/Middle Ordovician Series boundary in the Central Precordillera is placed at the middle part of the San Juan Formation, an open-platform carbonate unit. The Niquivil section is proposed as a GSSP for the base of the Middle Ordovician, which is marked by the FAD of the conodont Cooperignathus aranda (Cooper). It occurs in level NCA, at the upper part of the Oepikodus evae Zone (overlapping uppermost records of O. evae in association with other guide species); i.e., 100.15 m above the base of the reference section. The auxiliary Peña Sombría section from northern Precordillera records graptolites of the lower (but not lowest) Middle Ordovician in the Isograptus victoriae maximus Zone, few meters above the proposed boundary biohorizon. The range of C. aranda can be correlated with the I. victoriae lunatus Zone up to the lower part of the Undulograptus austrodentatus Zone in diverse sections of the world. C. aranda presents cosmopolitan distribution and occurs in virtually all environments. The proposed GSSP preserves a carbon-isotope record that provides an auxiliary marker of potential global application. Radiometric dating of K-bentonite samples, interbedded with carbonate strata yielding lower records of C. aranda, were recovered from the auxiliary Talacasto section in Central Precordillera (469.8 ± 2.3 Ma, U–Pb SHRIMP dating).Cooperignathus aranda (Cooper). It occurs in level NCA, at the upper part of the Oepikodus evae Zone (overlapping uppermost records of O. evae in association with other guide species); i.e., 100.15 m above the base of the reference section. The auxiliary Peña Sombría section from northern Precordillera records graptolites of the lower (but not lowest) Middle Ordovician in the Isograptus victoriae maximus Zone, few meters above the proposed boundary biohorizon. The range of C. aranda can be correlated with the I. victoriae lunatus Zone up to the lower part of the Undulograptus austrodentatus Zone in diverse sections of the world. C. aranda presents cosmopolitan distribution and occurs in virtually all environments. The proposed GSSP preserves a carbon-isotope record that provides an auxiliary marker of potential global application. Radiometric dating of K-bentonite samples, interbedded with carbonate strata yielding lower records of C. aranda, were recovered from the auxiliary Talacasto section in Central Precordillera (469.8 ± 2.3 Ma, U–Pb SHRIMP dating).(Cooper). It occurs in level NCA, at the upper part of the Oepikodus evae Zone (overlapping uppermost records of O. evae in association with other guide species); i.e., 100.15 m above the base of the reference section. The auxiliary Peña Sombría section from northern Precordillera records graptolites of the lower (but not lowest) Middle Ordovician in the Isograptus victoriae maximus Zone, few meters above the proposed boundary biohorizon. The range of C. aranda can be correlated with the I. victoriae lunatus Zone up to the lower part of the Undulograptus austrodentatus Zone in diverse sections of the world. C. aranda presents cosmopolitan distribution and occurs in virtually all environments. The proposed GSSP preserves a carbon-isotope record that provides an auxiliary marker of potential global application. Radiometric dating of K-bentonite samples, interbedded with carbonate strata yielding lower records of C. aranda, were recovered from the auxiliary Talacasto section in Central Precordillera (469.8 ± 2.3 Ma, U–Pb SHRIMP dating).Oepikodus evae Zone (overlapping uppermost records of O. evae in association with other guide species); i.e., 100.15 m above the base of the reference section. The auxiliary Peña Sombría section from northern Precordillera records graptolites of the lower (but not lowest) Middle Ordovician in the Isograptus victoriae maximus Zone, few meters above the proposed boundary biohorizon. The range of C. aranda can be correlated with the I. victoriae lunatus Zone up to the lower part of the Undulograptus austrodentatus Zone in diverse sections of the world. C. aranda presents cosmopolitan distribution and occurs in virtually all environments. The proposed GSSP preserves a carbon-isotope record that provides an auxiliary marker of potential global application. Radiometric dating of K-bentonite samples, interbedded with carbonate strata yielding lower records of C. aranda, were recovered from the auxiliary Talacasto section in Central Precordillera (469.8 ± 2.3 Ma, U–Pb SHRIMP dating).O. evae in association with other guide species); i.e., 100.15 m above the base of the reference section. The auxiliary Peña Sombría section from northern Precordillera records graptolites of the lower (but not lowest) Middle Ordovician in the Isograptus victoriae maximus Zone, few meters above the proposed boundary biohorizon. The range of C. aranda can be correlated with the I. victoriae lunatus Zone up to the lower part of the Undulograptus austrodentatus Zone in diverse sections of the world. C. aranda presents cosmopolitan distribution and occurs in virtually all environments. The proposed GSSP preserves a carbon-isotope record that provides an auxiliary marker of potential global application. Radiometric dating of K-bentonite samples, interbedded with carbonate strata yielding lower records of C. aranda, were recovered from the auxiliary Talacasto section in Central Precordillera (469.8 ± 2.3 Ma, U–Pb SHRIMP dating).Isograptus victoriae maximus Zone, few meters above the proposed boundary biohorizon. The range of C. aranda can be correlated with the I. victoriae lunatus Zone up to the lower part of the Undulograptus austrodentatus Zone in diverse sections of the world. C. aranda presents cosmopolitan distribution and occurs in virtually all environments. The proposed GSSP preserves a carbon-isotope record that provides an auxiliary marker of potential global application. Radiometric dating of K-bentonite samples, interbedded with carbonate strata yielding lower records of C. aranda, were recovered from the auxiliary Talacasto section in Central Precordillera (469.8 ± 2.3 Ma, U–Pb SHRIMP dating).Zone, few meters above the proposed boundary biohorizon. The range of C. aranda can be correlated with the I. victoriae lunatus Zone up to the lower part of the Undulograptus austrodentatus Zone in diverse sections of the world. C. aranda presents cosmopolitan distribution and occurs in virtually all environments. The proposed GSSP preserves a carbon-isotope record that provides an auxiliary marker of potential global application. Radiometric dating of K-bentonite samples, interbedded with carbonate strata yielding lower records of C. aranda, were recovered from the auxiliary Talacasto section in Central Precordillera (469.8 ± 2.3 Ma, U–Pb SHRIMP dating).C. aranda can be correlated with the I. victoriae lunatus Zone up to the lower part of the Undulograptus austrodentatus Zone in diverse sections of the world. C. aranda presents cosmopolitan distribution and occurs in virtually all environments. The proposed GSSP preserves a carbon-isotope record that provides an auxiliary marker of potential global application. Radiometric dating of K-bentonite samples, interbedded with carbonate strata yielding lower records of C. aranda, were recovered from the auxiliary Talacasto section in Central Precordillera (469.8 ± 2.3 Ma, U–Pb SHRIMP dating).I. victoriae lunatus Zone up to the lower part of the Undulograptus austrodentatus Zone in diverse sections of the world. C. aranda presents cosmopolitan distribution and occurs in virtually all environments. The proposed GSSP preserves a carbon-isotope record that provides an auxiliary marker of potential global application. Radiometric dating of K-bentonite samples, interbedded with carbonate strata yielding lower records of C. aranda, were recovered from the auxiliary Talacasto section in Central Precordillera (469.8 ± 2.3 Ma, U–Pb SHRIMP dating).Undulograptus austrodentatus Zone in diverse sections of the world. C. aranda presents cosmopolitan distribution and occurs in virtually all environments. The proposed GSSP preserves a carbon-isotope record that provides an auxiliary marker of potential global application. Radiometric dating of K-bentonite samples, interbedded with carbonate strata yielding lower records of C. aranda, were recovered from the auxiliary Talacasto section in Central Precordillera (469.8 ± 2.3 Ma, U–Pb SHRIMP dating).C. aranda presents cosmopolitan distribution and occurs in virtually all environments. The proposed GSSP preserves a carbon-isotope record that provides an auxiliary marker of potential global application. Radiometric dating of K-bentonite samples, interbedded with carbonate strata yielding lower records of C. aranda, were recovered from the auxiliary Talacasto section in Central Precordillera (469.8 ± 2.3 Ma, U–Pb SHRIMP dating).C. aranda, were recovered from the auxiliary Talacasto section in Central Precordillera (469.8 ± 2.3 Ma, U–Pb SHRIMP dating).
Herramientas para la gestión del uso público en espacios naturales: Procesos participativos; Tools for the management of public use4n wetlands: Public participation
De Paula, Malena; Huwiler, Cristina; Viñals, María José; Morant González, Maryland; Ferrer, Carlos; Cabrelles, Gemma; Rigoberto, Noelia; Quintana, Ruben Dario
La gestion del uso publico en areas naturales y especialmente en Humedales de Importancia Internacional(Sitios Ramsar), representa un importante reto para planificadores y gestores del territorio que tratan deconjugar la conservation de los valores ecologicos y culturales con la utilidad publica, en areas que se caracterizan por una gran fragilidad ecosistemica.El trabajo parte de la premisa de que la participation de las comunidades locales involucradas en laplanificacion y gestion del uso publico en humedales es la via para asegurar que la mayor parte de los beneficiosque se generen permanezcan en la comunidad y para que se garantice la conservation y restauracion de laintegridad ecologica de los humedales.En este documento se expone el diseño e implementation de herramientas metodologicas de una EstrategiaParticipativa. Se analizan a traves de diferentes casos de estudio los resultados de la aplicacion de dicha metodologia, a distintas situaciones de las comunidades locales respecto a los procesos participativos, en relationcon la planificacion de los humedales y el uso publico.; Community involvement and participation in management decision making for public use of natural areas, and particularly in Wetlands of International Importance (Ram sarsites) and other wetlands, have been recognized as the best way compatible with the maintenance of the cultural values and the natural properties of the ecosystem . This paper was conceived with the premise that local people involvement in wetlands management encouraged by a participative strategic can substantially contribute significantly to maintaining or restoring the ecological integrity of wetlands, as well as contributing to community well being and more equitable access to resources. Through the case studies presented here, the methodology is analyzed in different local communities situations from the point of view of participatory processes for the management of wetlands and the public use.
