Ciencia y Tecnología
El aporte de las cooperativas a las políticas públicas y el territorio: un análisis de las mediciones estadísticas en Argentina; Cooperatives’ contribution to public policies and territory: Analysis of Argentinian statistical measurements’; A contribuição das cooperativas para as políticas públicas e o território: uma análise das medidas estatísticas na Argentina
Castelao Caruana, Maria Eugenia
Introducción: en las últimas décadas, los poderes públicos nacionales y los organismos internacionales han incrementado su interés por la forma de organización cooperativa, y reconocen su capacidad de contribuir al abordaje de problemas sociales, económicos y ambientales. Metodología: la metodología de esta investigación se basa en el modelo analítico de políticas púbicas que propone comprender la lógica que encierra la acción de las instituciones políticas y de los actores involucrados en las intervenciones públicas desde el ángulo de su contribución a la solución de los problemas colectivos.Resultados: el trabajo estudia el papel de las cooperativas en las políticas públicas a partir del análisis de las intervenciones públicas de alcance nacional, vigentes en Argentina en el periodo 2003-2015. Por otra parte, se identifican y analizan las distintas fuentes de información disponibles en el país que podrían dar cuenta de las acciones que realizan estas entidades.Conclusiones: se plantea la necesidad de registrar y medir el peso económico y social de las coopera-tivas y el impacto de su participación en las políticas públicas a fin de producir un mejor conocimiento sobre la realidad del sector, fortalecer su imagen positiva y difundir esta forma de organización.; Introduction: In recent decades, national public authorities and international organizations have beco-me growingly interested in cooperative organization and recognize its possibility to contribute social, economic and environmental problems approach.Methodology: The methodology of this research is based on a public policies analytical model that aims to understand the logic that underlies political institutions and actors involved in public interventions’ actions with respect to their contribution to solve collective problems.Results: The paper studies the role of cooperatives in public policies based on the analysis of public interventions of national scope given in Argentina from 2003 to 2015. Also, the different sources of information available in the country that could disclose the actions carried out by these entities are identified and analyzed.Conclusions: There is a need to register and measure cooperatives’ economic and social importance and the impact of their participation in public policies in order to attain better understanding of the sector’s reality, strengthen its positive image and publicize this form of organization.; Introdução: nas últimas décadas, as autoridades públicas nacionais e as organizações internacionais aumentaram o seu interesse pela forma de organização cooperativa, e reconheceram a sua capacidade de contribuir para o tratamento de problemas sociais, económicos e ambientais.Metodologia: a metodologia da presente investigação baseia-se no modelo analítico de políticas públicas que propõe compreender a lógica em torno à ação das instituições políticas e os atores envolvidos em intervenções públicas, a partir do ângulo de sua contribuição para a solução de problemas coletivos.Resultados: o artigo estuda o papel das cooperativas nas políticas públicas a partir da análise de in-tervenções públicas de abrangência nacional, vigentes na Argentina no período 2003-2015. Por outro lado, identificam-se e analisam-se as diferentes fontes de informação disponíveis no país, que poderiam explicar as ações realizadas por essas entidades.Conclusões: expõe-se a necessidade de registrar e medir o peso econômico e social das cooperativas e o impacto de sua participação nas políticas públicas, a fim de melhor compreender a realidade do setor, fortalecer sua imagem positiva e disseminar essa forma de organização.
Positioning Latin America within the Southern Turn in Planning: Perspectives on an “Emerging Field”. Conclusion to the Special Issue on Latin America
Positioning Latin America within the Southern Turn in Planning: Perspectives on an “Emerging Field”. Conclusion to the Special Issue on Latin America
Galland, Daniel; Elinbaum, Pablo
The conclusion to this special issue on the state of planning in Latin America provides a series of critical reflections based on the cross-comparative analysis of its seven contributions. Rather than summarising the results embedded in the survey, we allude to the thematic questions posed in the introduction by responding with thought-provoking, argument-based counter-questions as revealed by each of the section headings comprising this conclusion. To make a contribution towards positioning planning in Latin America as an emerging “field” within the Southern turn in planning, the following sections suggest a series of research trajectories whose underlying rationales build on the exposed perceptions around significant planning problems across the region.
A “Field” Under Construction: The State of Planning in Latin America and the Southern Turn in Planning. Introduction to the Special Issue on Latin America
A “Field” Under Construction: The State of Planning in Latin America and the Southern Turn in Planning. Introduction to the Special Issue on Latin America
Galland, Daniel; Elinbaum, Pablo
This special issue takes a point of departure on the “southern turn in planning” with an emphasis on Latin America and seeks to contribute to the current wave of debates around international comparative planning. Its objective is to target the “state of the art” of planning interventions as well as contemporary forms of planning knowledge and academic scholarship across the region. In doing so, a number of key themes are identified through rationales ranging from the emergence of planning policies, practices and discourses to gaps between theory and practice, and then moving on to the state of planning education and the exchange of planning knowledge across different countries within the region. Based on these themes, the substance of the issue embraces inputs by academics with planning knowledge and expertise from Argentina, Mexico, Chile, Colombia, Uruguay, Brazil and Peru. The conclusion to the issue presents a cross-comparative analysis and synthesises a series of research axes aimed at designing a research agenda concerning planning in Latin America.
Natural resources and primary sector-dependent territories in Latin America
Natural resources and primary sector-dependent territories in Latin America
Gorenstein, Silvia Mirta; Ortiz, Ricardo
Recursos naturales y territorios primarizados en Latinoamérica. Area Development and Policy. La renovada discusión acerca de los problemas asociados con la especialización productiva y comercial de los países latinoamericanos en la exportación de productos básicos (agricultura, minería y energía) y materias primas a los países desarrollados se vuelve relevante debido a ciertas características de la era contemporánea: la deslocalización de las grandes corporaciones industriales y la lógica asociada al ‘capital mariposa’; el ascenso del capitalismo financiero y sus crisis; la revolución científico-tecnológica basada en tecnologías de información y comunicación; el liderazgo de nuevos jugadores en el comercio mundial con la expansión de la demanda de los países asiáticos y particularmente de China; y el aumento en los precios de los productos básicos.; A renewed discussion about the problems associated with the productive and commercial specialization of Latin American countries in the export of commodities (agricultural, mining and energy) and raw materials to developed countries is important due to certain characteristics of the contemporary era, namely: the productive offshoring of large industrial corporations and the associated logic of ‘butterfly capital’; the rise and crisis in particular of financialized capitalism; the scientific–technological revolution based on information and communications technologies; the leadership of new players in world trade with the expansion of demand from Asian countries and particularly from China; and the rise in commodity prices.; 南美洲自然资源和主要行业依赖地区]. Area Development and Policy. 由于当今世界呈现出新的发展特征,对拉丁美洲国家向发达国家出口(农业、矿产、能源)商品和原材料的过程中存在的生产和商业专业分工问题进行重新探讨具有重要意义。这些新的发展特征包括:大型工业企业的生产外包以及相关的“蝴蝶资本”逻辑;金融化资本主义的兴衰;基于信息与通信技术的科技革命;随着亚洲国家尤其是中国需求的扩大而出现的世界贸易新的领导者;以及商品价格的上涨。; Природные ресурсы и территории, зависимые от первичного сектора, в Южной Америке. Area Development and Policy. Возобновленное обсуждение проблем, связанных с производственной и коммерческой специализацией латиноамериканских стран в экспорте сырьевых товаров (сельскохозяйственных, минеральных и энергетических) в развитые страны, имеет важное значение в связи с определенными особенностями современной эпохи, а именно: производственным офшорингом крупных промышленных корпораций и связанной с этим логикой ‘капитала-бабочки’; подъемом и падением, в частности, финансового капитализма; научно-технической революцией, основанной на информационно-коммуникационных технологиях; лидерством новых игроков в мировой торговле с расширением спроса со стороны азиатских стран и особенно со стороны Китая; ростом цен на сырьевые товары.
Low Density Wood Impregnation with Water-Repellent Organosilicic Compounds
Low Density Wood Impregnation with Water-Repellent Organosilicic Compounds
Canosa, Guadalupe; Alfieri, Paula Vanesa; Giudice, Carlos Alberto
Many protective treatments for low density wood are applied by impregnationto give water-repellency and to control pathologies that usually have this substrate.The properties of Araucaria angustifolia , chemically modified by impregnationwith methyltriethoxysilane, n-octyltriethoxysilane and mixtures ofboth in several ratios, were investigated to achieve mainly high dimensionalstability, low capillary water absorption as well as satisfactory water vaporpermeability. The aforementioned impregnants produce the wood chemicalmodification, involving the reaction of hydroxyl groups of the wood with thehydrolysis products of alcoxysilanes. It is concluded that the organosiliconpolymers allow improving important characteristics of wood: 1) the non-occlusivecoating keeps the water vapor permeability unaltered; 2) the alkoxysilane type definesthe hydrophobicity and the continuity of coating formed on the porewall and finally; 3) the polymeric structure formed after finishing sol-gelprocess incises both on the capillary water absorption and the dimensionalstability. In addition, the studied treatments have the advantage of allowingthat the water vapor, which permeates through the organosilicon coatingplaced on cell wall, can exit by hydrophobic repulsion and thus, prevent faultsappearance generated by the condensed water inside of wood.
Fabrication of folic acid magnetic nanotheranostics: An insight on the formation mechanism, physicochemical properties and stability in simulated physiological media
Fabrication of folic acid magnetic nanotheranostics: An insight on the formation mechanism, physicochemical properties and stability in simulated physiological media
Azcona, Pamela Liliana; López Corral, Ignacio; Lassalle, Verónica Leticia
Nanodevices based on magnetite functionalized with folic acid (FA) with improved properties to be employed as theranostics in various types of cancer are here proposed. Two methodologies for FA incorporation were explored aiming to reach suitable loading efficiency as well as adequate stability of nanosystems in physiological media. To this end, simple adsorption and covalent binding of FA and some experimental conditions derived from both procedures were studied. A thorough physicochemical characterization was performed using all the formulations. The mechanism of the interaction between FA and magnetite nanoparticles (MNPs) was elucidated from characterization results supported by theoretical studies using spin-polarized density functional theory (DFT). Both data coincide in that the selective functional group of FA (pteridine group) remained available after FA binding MNPs. Such studies also demonstrated that any of FA carboxylate groups could be available to potentially link other molecule (i.e therapeutic agents). Besides, other issues that are not normally accomplished in reported articles were included; i.e the stability according to two different criteria: size evolution (expressed as hydrodynamic diameter) as a function of time in aqueous media; and the capacity FA retention in PBS, pH = 7.4. Recovered data indicated that the samples are stable at least 15 days in water and 4 h in buffer without significant modifications of their properties. The feasibility of these formulations to interact with simulated physiological fluid was also assayed. The results revealed that protein corona was formed around all the tested formulations leading to more stable nanodevices in terms of their hydrodynamic sizes and size evolution along the time. To complete the theranostic characteristic, Doxorubicin was added to the MNPs@FA by physical adsorption, to provide the therapeutic function. The satisfactory incorporation was verified by FTIR spectroscopy.
Plasma total cell-free DNA (cfDNA) is a surrogate biomarker for tumour burden and a prognostic biomarker for survival in metastatic melanoma patients
Plasma total cell-free DNA (cfDNA) is a surrogate biomarker for tumour burden and a prognostic biomarker for survival in metastatic melanoma patients
Valpione, S.; Gremel, G.; Mundra, P.; Middlehurst, P.; Galvani, E.; Girotti, Maria Romina; Lee, R.J.; Garner, G.; Dhomen, N.; Lorigan, P.C.; Marais, R.
Introduction Tumour burden is a prognostic biomarker in metastatic melanoma. However, tumour burden is difficult to measure and there are currently no reliable surrogate biomarkers to easily and reliably determine it. The aim of this study was to assess the potential of plasma total cell free DNA as biomarker of tumour burden and prognosis in metastatic melanoma patients. Materials and methods A prospective biomarker cohort study for total plasma circulating cell-free DNA (cfDNA) concentration was performed in 43 metastatic melanoma patients. For 38 patients, paired blood collections and scan assessments were available before treatment and at first response evaluation. Tumour burden was calculated as the sum of volumes from three-dimensional radiological measurements of all metastatic lesions in individual patients. Results Baseline cfDNA concentration correlated with pre-treatment tumour burden (ρ = 0.52, P < 0.001). Baseline cfDNA levels correlated significantly with hazard of death and overall survival, and a cut off value of 89 pg/μl identified two distinct prognostic groups (HR = 2.22 for high cfDNA, P = 0.004). Patients with cfDNA ≥89 pg/μl had shorter OS (10.0 versus 22.7 months, P = 0.009; HR = 2.22 for high cfDNA, P = 0.004) and the significance was maintained when compared with lactic dehydrogenase (LDH) in a multivariate analysis. We also found a correlation between the changes of cfDNA and treatment-related changes in tumour burden (ρ = 0.49, P = 0.002). In addition, the ratio between baseline cfDNA and tumour burden was prognostic (HR = 2.7 for cfDNA/tumour volume ≥8 pg/(μl*cm3), P = 0.024). Conclusions We have demonstrated that cfDNA is a surrogate marker of tumour burden in metastatic melanoma patients, and that it is prognostic for overall survival.
Landslide change detection based on Multi-Temporal airborne LIDAR-derived DEMs
Landslide change detection based on Multi-Temporal airborne LIDAR-derived DEMs
Mora, Omar E.; Lenzano, María Gabriela; Toth, Charles Karoly; Grejner-Brzezinska, Dorota A.; Fayne, Jessica V.
Remote sensing technologies have seen extraordinary improvements in both spatial resolution and accuracy recently. In particular, airborne laser scanning systems can now provide data for surface modeling with unprecedented resolution and accuracy, which can effectively support the detection of sub-meter surface features, vital for landslide mapping. Also, the easy repeatability of data acquisition offers the opportunity to monitor temporal surface changes, which are essential to identifying developing or active slides. Specific methods are needed to detect and map surface changes due to landslide activities. In this paper, we present a methodology that is based on fusing probabilistic change detection and landslide surface feature extraction utilizing multi-temporal Light Detection and Ranging (LiDAR) derived Digital Elevation Models (DEMs) to map surface changes demonstrating landslide activity. The proposed method was tested in an area with numerous slides ranging from 200 m2 to 27,000 m2 in area under low vegetation and tree cover, Zanesville, Ohio, USA. The surface changes observed are probabilistically evaluated to determine the likelihood of the changes being landslide activity related. Next, based on surface features, a Support Vector Machine (SVM) quantifies and maps the topographic signatures of landslides in the entire area. Finally, these two processes are fused to detect landslide prone changes. The results demonstrate that 53 out of 80 inventory mapped landslides were identified using this method. Additionally, some areas that were not mapped in the inventory map displayed changes that are likely to be developing landslides.
Sequential Bayesian Experimental Design for Process Optimization with Stochastic Binary Outcomes
Sequential Bayesian Experimental Design for Process Optimization with Stochastic Binary Outcomes
Luna, Martín Francisco; Martínez, Ernesto Carlos
For innovative products, the issue of reproducibly obtaining their desired end-use properties at industrial scale is the main problem to be addressed and solved in process development. Lacking a reliable first-principles process model, a Bayesian optimization algorithm is proposed. On this basis, a short of sequence of experimental runs for pinpointing operating conditions that maximize the probability of successfully complying with end-use product properties is defined. Bayesian optimization is able to take advantage of the full information provided by the sequence of experiments made using a probabilistic model (Gaussian process) of the probability of success based on a one-class classification method. The metric which is maximized to decide the conditions for the next experiment is designed around the expected improvement for a binary response. The proposed algorithm's performance is demonstrated using simulation data from a fed-batch reactor for emulsion polymerization of styrene.
Goal-directed Design of Dynamic Experiments for Cybernetic Models of Bioreactors
Goal-directed Design of Dynamic Experiments for Cybernetic Models of Bioreactors
Luna, Martín Francisco; Martínez, Ernesto Carlos
The distinctive feature of cybernetic models of bioreactors is their capacity to account for regulatory mechanisms in a cell metabolism by modeling the synthesis of enzymes and their activities. From a process engineering viewpoint, to guarantee its predictive capabilities regarding one or more process objective or goals (e.g. optimization, controllability, etc.), experimental data used to fit a cybernetic model parameters should be the most informative bearing in mind the adequacy of the resulting model to describe the specific objective of interest. To excite the most relevant metabolic modes in the cybernetic model, a dynamic experiment is optimally designed by accounting for the sensitivity of the chosen objective to operating conditions. The bioreactor feeding profile and sampling times are selected to maximize a global sensitivity index. As a case study, biomass production or fermentation to ethanol conversion in the fed-batch cultivation of Saccharomyces Cerevisiae are considered as alternative objectives.
Visualization of the Diffusion Pathway of Protons in (NH4)2Si0.5Ti0.5P4O13 as an Electrolyte for Intermediate-Temperature Fuel Cells
Visualization of the Diffusion Pathway of Protons in (NH4)2Si0.5Ti0.5P4O13 as an Electrolyte for Intermediate-Temperature Fuel Cells
Sun, Chunwen; Chen, Lanli; Shi, Siqi; Reeb, Berthold; Lopez, Carlos Alberto; Alonso, José Antonio; Stimming, Ulrich
We demonstrate that (NH4)2Si0.5Ti0.5P4O13 is an excellent proton conductor. The crystallographic information concerning the hydrogen positions is unraveled from neutron-powder-diffraction (NPD) data for the first time. This study shows that all the hydrogen atoms are connected though H bonds, establishing a two-dimensional path between the [(Si0.5Ti0.5)P4O132-]n layers for proton diffusion across the crystal structure by breaking and reconstructing intermediate H-O=P bonds. This transient species probably reduces the potential energy of the H jump from an ammonium unit to the next neighboring NH4+ unit. Both theoretical and experimental results support an interstitial-proton-conduction mechanism. The proton conductivities of (NH4)2Si0.5Ti0.5P4O13 reach 0.0061 and 0.024 S cm-1 in humid air at 125 and 250 °C, respectively. This finding demonstrates that (NH4)2Si0.5Ti0.5P4O13 is a promising electrolyte material operating at 150-250 °C. This work opens up a new avenue for designing and fabricating high-performance inorganic electrolytes.
Políticas Estéticas: El caso Saer y la persistencia de la autonomía
Políticas Estéticas: El caso Saer y la persistencia de la autonomía
Abbate, Florencia
El objetivo de es artículo será la revisión del concepto de autonomía del arte y su puesta en relación con la obra narrativa y ensayística de Juan José Saer. Se examinan de modo crítico aquellas lecturas que implícitamente han tendido a interpretarlo retomando de modo epigonal dicotomías como arte por el arte vs. arte comprometido o formalismo vs. realismo. Sostenemos que en este autor la defensa del pilar moderno de la autonomía estética no se opone a aquellas visiones que le atribuyen al arte una función social sino que, por el contrario, asume en su obra un valor político. Para ello, nos basamos en algunas nociones de J. Ranciére, cuya filosofía redefine la estética como algo no sólo perteneciente al campo de las formas sensibles sino también de lo social y lo político, y pensamos lo político como una "redistribución de lo sensible".
Galectins: key players at the frontiers of innate and adaptive immunity
Galectins: key players at the frontiers of innate and adaptive immunity
Martínez Allo, Verónica Candela; Toscano, Marta Alicia; Pinto, Nicolás Alejandro; Rabinovich, Gabriel Adrián
The proper function of the immune system entails multiple regulatory pathways aimed at modulating immunogenic and tolero-genic functions of immune cells. Galectins, a family of carbohydrate-binding proteins, control a variety of biological processes involved in activation, differentiation, trafficking and survival of immune cells. In this review we summarize pioneer work and emerging findings highlighting selected functions of galectins as regulatory checkpoints that control innate and adaptive immune cell programs.
CSDC2, a cold shock domain RNA-binding protein in decidualization
CSDC2, a cold shock domain RNA-binding protein in decidualization
Vallejo, Griselda; Mestre Citrinovitz, Ana Cecilia; Winterhager, Elke; Saragueta, Patricia Esther
RNA-binding proteins (RBPs) have been described for cancer cell progression and differentiation, although there is still much to learn about their mechanisms. Here, using in vivo decidualization as a model, we describe the role of RBP cold shock domain containing C2 (CSDC2) in the endometrium. Csdc2 messenger RNA expression was differentially regulated depending on time and areas of decidua development, with the most variation in antimesometrium (AM) and, to a lesser degree, in the junctional zone (JZ). Immunohistochemistry of CSDC2 showed a preferentially cytoplasmic localization at AM and JZ, and nuclear localization in underneath myometrium and mesometrium (M). Cytoplasmic localization coincided with differentiated, DESMIN-marked areas, while nuclear localization coincides with proliferative zones. Uterine suppression of CSDC2 through intrauterine-injected-specific small interfering RNA (siRNA) led to abnormal decidualization in early pregnancy, with more extended antimesometrial area and with poor M development if compared with control siRNA-injected animals. These results suggest that CSDC2 could be a regulator during decidua development.
Estudio de los mecanismos moleculares y celulares de la entrada y propagación del Virus de la Diarrea Viral Bovina
Estudio de los mecanismos moleculares y celulares de la entrada y propagación del Virus de la Diarrea Viral Bovina
Merwaiss, Fernando; Alvarez, Diego Ezequiel; Czibener, Cecilia
El virus de la diarrea viral bovina (BVDV) es un pestivirus patógeno del ganado vacuno cercanamente relacionado al virus de la hepatitis C (HCV) dentro de la familia Flaviviridae. La infección con BVDV reduce la productividad causando pérdidas económicas para la industria ganadera. La partícula viral comprende una membrana lipídica asociada a las glicoproteínas de envoltura Erns, E1 y E2, que rodean a la nucleocápside que contiene el genoma viral, el cual consiste en una única molécula de ARN simple cadena de polaridad positiva. E2 es el principal determinante antigénico en el animal infectado y produce una respuesta inmune con anticuerpos neutralizantes contra BVDV. A su vez cumple un rolfundamental para la entrada del virus a la célula huésped dado que interacciona con receptores en la superficie de la célula que median la endocitosis de la partícula viral, y forma un complejo con E1 que es esencial en la fusión de la envoltura del virus con la membrana del endosoma en medio ácido para liberar el genoma de ARN en el citoplasmade la célula infectada. La reciente determinación de la estructura cristalina de E2 ha abierto nuevas perspectivas en el estudio del mecanismo molecular de la entrada de BVDV. En este trabajo de tesis se desarrollaron nuevas herramientas genéticas y moleculares con elobjetivo de estudiar el mecanismo de entrada y propagación de BVDV, haciendo foco fundamentalmente en el rol protagónico de la glicoproteína de envoltura E2.En la primera parte de este trabajo se empleo genética invesa para producir una versión recombinante de BVDV que expresa GFP en el citoplasma de células infectadas. Utilizando este virus desarrollamos ensayos basados en la detección de GFP por microscopia de fluorescenica y citometría de flujo mediante los que pudimos demostrar que la expresión de dicha proteina funciona como reportero de la replicación de BVDV. Por otro lado se desarrolló un sistema de expresión y marcación sitio específica con biotina in vivo para la proteína de envoltura viral E2 que permitió producir una proteína recombinante marcada homogéneamente. La unión especifica de esta proteína recombinante a células susceptibles y su capacidad de bloquear la entrada de BVDV,sugieren que la misma mantiene un plegamiento y funcionalidad correctos.A partir de la bibliografía referida a las funciones de E2 y basándose en un análisis de conservación de secuencias se identificaron en la estructura de la proteína posibles motivos funcionales. En particular, analizamos el rol de un motivo de estructura tipo β-hairpin expuesto al solvente como posible responsable de la interacción con receptores. Sediseñaron mutaciones en dicha region, las cuales en el contexto de la proteína soluble resultaron en una disminucion de su capacidad de bloquear la entrada de BVDV. A continuación, se generó un virus recombinante portando las mutaciones en el β-hairpin y se observó que la infectividad de dicho virus está severamente disminuida con respecto alvirus, indicando que dicha región está involucrada en la interacción con receptores celulares.En la segunda parte de este trabajo se construyó una pareja de virus recombinantes citopático y no citopático que expresa una versión de E2 en fase con la proteína fluorescente mCherry en su extremo amino terminal. A través de la detección de mCherry se pudieron identificar células infectadas y seguir así la propagación de la infección en células vivas. Empleando esta herramienta nos propusimos estudiar si BVDV tiene la capacidad de propagar en forma directa de célula a célula. Para esto se diseñaron ensayos de co-cultivo, donde se pudo observar la propagación de la infección viral desde células productoras de virus hacia células blanco aun en presencia de suero neutralizante en el medio. De esta forma demostramos por primera vez la existencia de propagación célula a célula en pestivirus. Con estas mismas herramientas comenzamos a estudiar cuales son los factores virales y celulares que median este tipo de propagación, hallando que la misma depende de la interacción de E2 con receptores específicos.
Theoretical modelling of chiral modifier/substrate interaction for Enantioselective Hydrogenation of p-Isobutylacetophenone
Theoretical modelling of chiral modifier/substrate interaction for Enantioselective Hydrogenation of p-Isobutylacetophenone
Recupero, Francisco; Casella, Mónica Laura; Ruggera, José Fernando
Se estudió a nivel DFT la interacción entre el modificador quiral y el sustrato para la reacción de hidrogenación enantioselectiva del tipo de Orito. Se realizó el modelado molecular a nivel DFT para estudiar la interacción entre el (R)-(-)-1-aminoindano y (S)-(+)-1-aminoindano como modificadores quirales y la p-isobutilacetofenona (intermediario en la síntesis del ibuprofeno). A partir de los cálculos teóricos e implementando un análisis de interacciones no covalentes, se demostró que la interacción responsable de la formación del complejo entre el modificador quiral y el sustrato es un enlace tipo puente de hidrógeno. Teniendo en cuenta las energías libres para la formación de cada complejo se calculó de forma teórica los excesos enantioméricos utilizando cada modificador quiral, encontrándose un exceso de alrededor del 30% del enantiómero R del producto cuando se utiliza el (R)-(-)-1-aminoindano, mientras que el exceso sería 30% pero para el enantiómero S del producto cuando se utiliza como modificador el (S)-(+)-1-aminoindano.; DFT level calculations were carried out to study the interaction between chiral modifier and substrate for Orito type enantioselective hydrogenation. Molecular modelling on a DFT level was developed to study the interaction between (R)-(-)-1-aminoindane and (S)-(+)-1-aminoindane as chiral modifiers and pisobutylacetophenone(intermediary the synthesis of Ibuprofen). Judging from theoretical calculations and implementing a non-covalent interaction analysis, it was shown that the interaction responsible for the formation of a complex between chiral modifier and substrate is a hydrogen bond. Taking into account the free energies of formation for each complex, a theoretical calculation was performed for the enantiomeric excess obtained from either chiral modifier, finding an excess of about 30% of the R enantiomer product when using (R)-(-)-1-aminoindane, while the excess would be of 30% for the S enantiomer product if the modifier is (S)-(+)-1-aminoindane.
Nuevos territorios: vida, literatura y subjetivación
Nuevos territorios: vida, literatura y subjetivación
Cámara, Mario Cesar
El trabajo aborda textos de Clarice Lispector, La hora de la estrella, de Mario Bellatín, Salón de Belleza, y de Joao Gilberto Noll, Lorde, a partir del concepto de "vidas precarias" desarrollado por Judith Butler en su libro homónimo. El recorrido plantea una breve historización del realismo literario y luego plantea las diferencias que estarían estableciendo con aquella tradición los textos literarios mencionados.
Nuevos territorios: vida, literatura y subjetivación
Nuevos territorios: vida, literatura y subjetivación
Cámara, Mario Cesar
El trabajo aborda textos de Clarice Lispector, La hora de la estrella, de Mario Bellatín, Salón de Belleza, y de Joao Gilberto Noll, Lorde, a partir del concepto de "vidas precarias" desarrollado por Judith Butler en su libro homónimo. El recorrido plantea una breve historización del realismo literario y luego plantea las diferencias que estarían estableciendo con aquella tradición los textos literarios mencionados.
A crustacean lobula plate: Morphology, connections, and retinotopic organization
A crustacean lobula plate: Morphology, connections, and retinotopic organization
Bengochea, Mercedes; Berón de Astrada, Martín; Tomsic, Daniel; Sztarker, Julieta
The lobula plate is part of the lobula complex, the third optic neuropil, in the optic lobes of insects. It has been extensively studied in dipterous insects, where its role in processing flow-field motion information used for controlling optomotor responses was discovered early. Recently, a lobula plate was also found in malacostracan crustaceans. Here, we provide the first detailed description of the neuroarchitecture, the input and output connections and the retinotopic organization of the lobula plate in a crustacean, the crab Neohelice granulata using a variety of histological methods that include silver reduced staining and mass staining with dextran-conjugated dyes. The lobula plate of this crab is a small elongated neuropil. It receives separated retinotopic inputs from columnar neurons of the medulla and the lobula. In the anteroposterior plane, the neuropil possesses four layers defined by the arborizations of such columnar inputs. Medulla projecting neurons arborize mainly in two of these layers, one on each side, while input neurons arriving from the lobula branch only in one. The neuropil contains at least two classes of tangential elements, one connecting with the lateral protocerebrum and the other that exits the optic lobes toward the supraesophageal ganglion. The number of layers in the crab's lobula plate, the retinotopic connections received from the medulla and from the lobula, and the presence of large tangential neurons exiting the neuropil, reflect the general structure of the insect lobula plate and, hence, provide support to the notion of an evolutionary conserved function for this neuropil.
First case of bacteraemia due to Acinetobacter schindleri harbouring blaNDM-1 in an immunocompromised patient
First case of bacteraemia due to Acinetobacter schindleri harbouring blaNDM-1 in an immunocompromised patient
Montaña, Sabrina Daiana; Palombarani, Susana; Carulla, M.; Kunst, A.; Rodriguez, C.H.; Nastro, Marcela; Vay, C.; Ramirez, M.S.; Almuzara, Marisa
Clinically significant NDM-1-producing Acinetobacter schindleri has not yet been described in the literature. We report the first case of bacteraemia due to an A. schindleri strain harbouring blaNDM-1 recovered from an immunocompromised patient. Our report reinforces the fact that NDM-1 can easily be acquired by Acinetobacter species.
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