A gynandromorph of Xylocopa augusti and an unusual record of X. iris from Brazil (Hymenoptera: Apidae: Xylocopini)

We describe and illustrate for the first time a mixed gynandromorph of Xylocopa(Neoxylocopa) augusti Lepeletier de Saint Fargeau from Buenos Aires, Argentina. Also, we document and discuss a historical specimen of the Old World carpenter bee X. (Copoxyla) iris (Christ) possibly collected in Brazil.Fil: Lucia, Mariano. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. División Entomología; ArgentinaFil: Villamil, Soledad Camila. Universidad Nacional del Sur. Departamento de Agronomía. Laboratorio de Estudios Apícolas; ArgentinaFil: Gonzalez, Victor H.. University of Kansas; Estados Unido

El paso de Joan Corominas por Argentina

El presente artículo apunta a rescatar los hechos más importantes relacionados con el paso de Joan Corominas por Mendoza (Argentina), adonde se exilió al término de la Guerra Civil española. Desde una metodología historiográfica basada en el rastreo de fuentes y su interpretación contextualizada, se toman en consideración los siguientes puntos: su desempeño como docente en la Universidad Nacional de Cuyo, la fundación del Instituto de Lingüística, la creación de la revista Anales del Instituto de Lingüística (en el año 1940) y la publicación de un amplio abanico de artículos científicos y de divulgación científica. Además, se destaca que el filólogo catalán elaboró en Mendoza su Diccionario Crítico Etimológico de la Lengua Castellana (1954-1957). Se insistirá sobre todo en las publicaciones del autor, principalmente en las de divulgación, que constituyen el aspecto menos revisado de la etapa mendocina de Corominas.Fil: Gonzalez, Daniela Soledad. Universidad Nacional de Cuyo; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Life cycle analysis of Jatropha curcas as a sustainable biodiesel feedstock in Argentina

Despite constant changes to the industry in recent years, Argentina remains one of the most important producers of biodiesel in the world. Approximately 90% of the biodiesel produced in Argentina is from soybean, a fact which has raised concern over the fuel´s sustainability. For this reason, alternative crops such as Jatropha curcas are being explored. The aim of this study is to assess the environmental impact of Jatropha-based biodiesel for the specific case of Argentina through life cycle assessment (LCA). The processes considered in this study include Jatropha seed cultivation, seed transportation, oil extraction, and transesterification. Two cultivation scenarios are examined in order to explore trade-offs between land use type and agricultural inputs. This study also incorporates land and water use, which are typically omitted from LCA due to complexity and lack of available information. Inventory data for the system were collected and analyzed using the ReCiPe impact assessment method. The results show a 21% reduction of kg CO2 equivalent for the overall Jatropha biodiesel production process when using fertile land with low-input agriculture instead of marginal land use with fertilizer and irrigation.Fil: Beaver, Alexa. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Planta Piloto de Ingeniería Química. Universidad Nacional del Sur. Planta Piloto de Ingeniería Química; ArgentinaFil: Gonzalez Castaño, Fabio Antonio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Planta Piloto de Ingeniería Química. Universidad Nacional del Sur. Planta Piloto de Ingeniería Química; ArgentinaFil: Díaz, María Soledad. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Planta Piloto de Ingeniería Química. Universidad Nacional del Sur. Planta Piloto de Ingeniería Química; Argentin

Synthesis of fused tetrazolo iminosugars from azido monosaccharide derivatives

Synthesis of fused tetrazolo iminosugars from azido monosaccharide derivativesUniversidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Development of type II superlattice infrared detectors monolithically integrated on silicon substrates

The project’s objective is the development of an InAs/GaSb type II superlattice (T2SL) medium wavelength infrared photodiode directly grown on Si substrate for the use of an infrared single pixel photodiode. The T2SL has been selected as the replacement for the state-of-the-art CdHgTe (CMT). The use of Si substrate will help with the integration into the Si-based technology by reducing the fabrication process and costs. The T2SL is a photon detector with overlapping multiple quantum well structure and a type 2 bandgap alignment. The T2SL are fabricated using a combination of materials from the group III-V in order to achieve a well-controlled ultra-thin heterostructures using molecular beam epitaxy as a growth technique. The structure within the active region is designed to enhance the performance of the T2SL architecture by manipulating the thickness and doping of each layer. The direct growth of a T2SL structure on the Si substrate has achieved similar structural and optical properties when compared to that grown on the GaAs substrate. The Si architecture has an absorption edge of 5.365μm when measured at 70K: dark current density at -1V is 4x101A/cm2; responsivity (R) peak is 1.2A/W; quantum efficiency (QE) at -0.1V is 32.5%; and specific detectivity (D*) peak is 1x109cmHz½/W. The pπBn has best architecture over GaAs substrate due to the wide bandgap unipolar barrier. The pπBn has an absorption edge of 6.5 μm when measured at 77K: dark current density under -0.6V is 5x10-3A/cm2; R peak is 0.6A/W; QE at 0V and 3.25μm is 23%; and D* peak is 1x1011cmHz½/W. These results demonstrate that the D* of the pπBn structure is just one order of magnitude smaller than the state-of-the-art CMT detector which is 2x1012cmHz1/2W

The Cross of Snow

The Cross of Snow” is an original choral composition based on a poem of the same name by Henry Wadsworth Longfellow. Longfellow was an internationally renowned American poet in his lifetime. The poem was written eighteen years after the death of his wife whose dress accidentally caught on fire. He unsuccessfully attempted to extinguish the flames with his own body. The first part of the poem describes his sleepless nights where the image of a dead loved one’s face stares at him from a wall. Longfellow’s mention of martyrdom and its inability to lead fire to its “repose” references his futile attempts to extinguish the flames that engulfed his wife with his own body. His failed attempts to save his wife is then contrasted with the unimaginably blessed story that was his wife’s life. The final lines of the poem then invoke the title as a metaphor for carrying the guilt from her death and the loss of the ability to see beauty in the world. Through the use of text painting, I portray the haunting guilt that comes with the loss of a spouse, but also the love and joy that comes with celebrating their life. Repetition of the line “long dead” emphasizes this lingering guilt that is brought to a musical climax as he remembers his failed attempt to save her. The lines which recall her life are portrayed by a soaring lyrical melody and dense harmonic texture. The piece ends the same way it began to show that the emotional wounds from his spouse\u27s death never truly healed. The combination of the contemporary American choral style with the text of an iconic American poet makes work a significant contribution to the contemporary American choral repertoire. Copyrigh

Revisiting the mechanism of the mono nuclear copper-catalyzed cycloaddition of azide and alkynes (CuAAC) by the topology of ....

Comunicación presentada y aceptada en el CHITEL2013, XXXIX International Conference THEORETICAL CHEMISTS OF LATIN EXPRESSION (XXXIX Congreso Internacional de Químicos de Expresión Latina).Se analiza el mecanismo de la reacción de cicloadición, catalizada por Cu(I), de azidas a alquinos (CuAAC), haciendo uso de métodos DFT y de herramientas de análisis de la densidad electrónica basadas en la topología de su laplaciana

Structure, kinetic characterization and subcellular localization of the two ribulose 5-phosphate epimerase isoenzymes from Trypanosoma cruzi

The enzyme of the pentose phosphate pathway (PPP) ribulose-5-phosphate-epimerase (RPE) is encoded by two genes present in the genome of Trypanosoma cruzi CL Brener clone: TcRPE1 and TcRPE2. Despite high sequence similarity at the amino acid residue level, the recombinant isoenzymes show a strikingly different kinetics. Whereas TcRPE2 follows a typical michaelian behavior, TcRPE1 shows a complex kinetic pattern, displaying a biphasic curve, suggesting the coexistence of -at least-two kinetically different molecular forms. Regarding the subcellular localization in epimastigotes, whereas TcRPE1 is a cytosolic enzyme, TcRPE2 is localized in glycosomes. To our knowledge, TcRPE2 is the first PPP isoenzyme that is exclusively localized in glycosomes. Over-expression of TcRPE1, but not of TcRPE2, significantly reduces the parasite doubling time in vitro, as compared with wild type epimastigotes. Both TcRPEs represent single domain proteins exhibiting the classical α/β TIM-barrel fold, as expected for enzymes with this activity. With regard to the architecture of the active site, all the important amino acid residues for catalysis -with the exception of M58- are also present in both TcRPEs models. The superimposition of the binding pocket of both isoenzyme models shows that they adopt essentially identical positions in the active site with a residue specific RMSD < 2Å, with the sole exception of S12, which displays a large deviation (residue specific RMSD: 11.07 A). Studies on the quaternary arrangement of these isoenzymes reveal that both are present in a mixture of various oligomeric species made up of an even number of molecules, probably pointing to the dimer as their minimal functional unit. This multiplicity of oligomeric species has not been reported for any of the other RPEs studied so far and it might bear implications for the regulation of TcRPEs activity, although further investigation will be necessary to unravel the physiological significance of these structural findings.Fil: Gonzalez, Soledad Natalia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Biotecnológicas. Instituto de Investigaciones Biotecnológicas "Dr. Raúl Alfonsín" (sede Chascomús). Universidad Nacional de San Martín. Instituto de Investigaciones Biotecnológicas. Instituto de Investigaciones Biotecnológicas "Dr. Raúl Alfonsín" (sede Chascomús); ArgentinaFil: Valsecchi, Wanda Mariela. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Química y Físico-Química Biológicas "Prof. Alejandro C. Paladini". Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Instituto de Química y Físico-Química Biológicas; ArgentinaFil: Maugeri, Dante. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Biotecnológicas. Instituto de Investigaciones Biotecnológicas "Dr. Raúl Alfonsín" (sede Chascomús). Universidad Nacional de San Martín. Instituto de Investigaciones Biotecnológicas. Instituto de Investigaciones Biotecnológicas "Dr. Raúl Alfonsín" (sede Chascomús); ArgentinaFil: Delfino, Jose Maria. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Química y Físico-Química Biológicas "Prof. Alejandro C. Paladini". Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Instituto de Química y Físico-Química Biológicas; ArgentinaFil: Cazzulo, Juan Jose. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Biotecnológicas. Instituto de Investigaciones Biotecnológicas "Dr. Raúl Alfonsín" (sede Chascomús). Universidad Nacional de San Martín. Instituto de Investigaciones Biotecnológicas. Instituto de Investigaciones Biotecnológicas "Dr. Raúl Alfonsín" (sede Chascomús); Argentin

Intramolecular [3+2] Cycloaddition of Fused Azolo-Azepanes from Azido Monosaccharides Derivatives

Síntesis de bicíclicos compuestos empleando epoxiamidas como material de partida. Obtención de tetrazolo azepanos con posible actividad biológica.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech