1,469 research outputs found

    Expanding Directions, Exploding Parameters: Culture and Nation in LatCrit Coalitional Imagination

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    The articles and commentaries in this Symposium are excellent points of departure for reflecting upon the advances thus far achieved in the evolution of this still very young community of scholars. The articles and commentaries that follow this brief Introduction comprise the second free-standing law review Symposium on LatCrit theory organized specifically in response to student interests and initiatives. The timing is fitting, for this Symposium also coincides with the fifth anniversary of LatCrit theory\u27s emergence in the American legal academy. Since then, five annual conferences and four additional colloquia have produced, in total, nine published symposia in both mainstream and of color law journals. This record reflects and affirms LatCrit theory\u27s original commitment to collaboration with student law review editors, especially those of color, in the production of this new critical legal discourse on Latinas/os, policy, and society. This textual recordincluding this very Symposium-also attests to LatCrit theory\u27s expanding directions and exploding parameters. Indeed, this Symposium effectively celebrates and continues the LatCrit experiment that, in 1995, was, like Carlos\u27 dreams, little more than a will to imagine and believe

    Expanding Directions, Exploding Parameters: Culture and Nation in LatCrit Coalitional Imagination

    Get PDF
    The articles and commentaries in this Symposium are excellent points of departure for reflecting upon the advances thus far achieved in the evolution of this still very young community of scholars. The articles and commentaries that follow this brief Introduction comprise the second free-standing law review Symposium on LatCrit theory organized specifically in response to student interests and initiatives. The timing is fitting, for this Symposium also coincides with the fifth anniversary of LatCrit theory\u27s emergence in the American legal academy. Since then, five annual conferences and four additional colloquia have produced, in total, nine published symposia in both mainstream and of color law journals. This record reflects and affirms LatCrit theory\u27s original commitment to collaboration with student law review editors, especially those of color, in the production of this new critical legal discourse on Latinas/os, policy, and society. This textual recordincluding this very Symposium-also attests to LatCrit theory\u27s expanding directions and exploding parameters. Indeed, this Symposium effectively celebrates and continues the LatCrit experiment that, in 1995, was, like Carlos\u27 dreams, little more than a will to imagine and believe

    Changes in seed weight in response to different sources: sink ratio in oilseed rape

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    Little knowledge exists about the degree of source, sink and source: sink limitations on mean seed weight in oilseed rape (Brassica napus L.). The objective of this work was to analyze the nature and magnitude on seed weight response to assimilate availability during the effective seed-filling period in oilseed rape. Three Argentinean varieties, Eclipse, Impulse, and Master, were grown under field conditions, and at the beginning of the effective seed filling period, a broad range of source: sink manipulation combinations were produced. Source manipulations consisted of two incoming radiation (R) level reductions: 0% (Rn) and ~50% (Rs) combined with three different sources: sink treatments were applied: C, control; PR, ~50% pod removal, and D, 100% defoliation. Rs significantly reduced yield (15%) and MSW (12%) with respect to Rn, without significant effects on the rest of the sub yield components. Source:sink manipulation treatments significantly affected all yield components. PR diminished yield by 29%, reducing ca. 40% seeds pl-1 by reductions pods pl-1 (41%) with respect to Rn, whereas PR increased MSW by 19%, counterbalancing the reduction in seeds pl-1 and thereby in yield. When considering different seed positions along the main raceme, Rs reduced MSW by 12% independently of seed positions onto the raceme. On the contrary, PR increased MSW in average 17% with respect to C. Results reported here suggest that oilseed rape has source: sink co-limitation during the effective seed filling period, which is apparently higher than wheat and lower than maize. DOI: http://dx.doi.org/10.3329/ijarit.v4i1.21091 Int. J. Agril. Res. Innov. & Tech. 4 (1): 44-52, June, 201

    Depósitos de glaciares rocosos en Sierra Nevada (Granada)

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    En las cumbres de Sierra Nevada aparecen depósitos de morfologia acordonada que están constituidos por acumulaciones de cantos angulosos de gran tamaño y una pequeña o nula proporción en matriz. Estos han sido interpretados como depósitos de glaciares rocosos, generados en una última crisis climatica acontecida entre los 13.000 y 10.000 años B.PAmong the variety of deposits in the high mountain zone of Sierra Nevada, some coarse-grained detritic acumulations are worthy to remark. These appear related to glacial scarps and have been interpreted as ancien rock glaciers deposits. Two types have been distinguished: the first has a string-like morfology, the matrix is very scarce and hollow can be found between the pebbles; the second tends to show lobulate forms and higher contents of matrix. In both cases the pebbles are extremely angular and heterometric. The mechanism which probably originated these depositional forms has been gravitational displacing of a rock fragments mass with interstitial ice, wich confered a plastic behaviour to the assemblage. The age for these processes is estimate between 13.000 and 10.000 years B.

    Synthesis of IAN-type N,N-Ligands via Dynamic Kinetic Asymmetric Buchwald-Hartwig Amination

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    The Pd-catalyzed coupling of racemic heterobiaryl bromides, triflates, or nonaflates with aryl/alkyl primary amines using QUINAP as the ligand provides the corresponding axially chiral heterobiaryl amines with excellent yields and enantioselectivities. Reactivity and structural studies of neutral and cationic oxidative addition intermediates support a dynamic kinetic asymmetric amination mechanism based on the labilization of the stereogenic axis in the latter and suggest that coordination of the amine to the Pd center is the stereodetermining step.Ministerio de Ciencia e Innovación CTQ2013-48164-C2-1-P, CTQ2013-48164-C2-2-P, RYC-2013-12585 for A.R.European FEDER FundsJunta de Andalucía 2012/FQM 1078

    Dynamic Kinetic Resolution of Hetero biaryl Ketones by Zinc- Catalyzed Asymmetr ic Hydrosil ylation

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    Adiastereo- and highly enantioselective dynamic kinetic resolution (DKR) of configurationally labile hetero- biaryl ketones is described. The DKR proceeds by zinc- catalyze dhydrosilylation of the carbonyl group ,thus leading to secondary alcohols bearing axial and central chirality .The strategy relies on the labilization of the stereogenic axis that takes place thanks to aLewis acid–base interaction between anitrogen atom in the heterocycle and the ketone carbonyl group .The synthetic utility of the methodology is demonstrated through stereospecific transformations into either N,N-ligands or appealing axially chiral, bifunctional thiourea organocata- lysts.Ministerio de Ciencia e Innovación (Grants CTQ2016-76908-C2-1-P, CTQ2016-76908-C2-2-P, contract RYC-2013-12585)European FEDER FundsJunta de Andalucía (Grant 2012/FQM 10787)European Union - Marie Skłodowska-Curie (COFUND—Grant Agreement n 8 8 291780

    A Dynamic Kinetic Asymmetric Heck Reaction for the Simultaneous Generation of Central and Axial Chirality

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    A highly diastereo- and enantioselective, scalable Pd-catalyzed dynamic kinetic asymmetric Heck reaction of heterobiaryl sulfonates with electron-rich olefins is described. The coupling of 2,3-dihydrofuran or N-boc protected 2,3-dihydropyrrole with a variety of quinoline, quinazoline, phthalazine, and picoline derivatives takes place with simultaneous installation of central and axial chirality, reaching excellent diastereo- and enantiomeric excesses when in situ formed [Pd0/DM-BINAP] was used as the catalyst, with loadings reduced down to 2 mol % in large scale reactions. The coupling of acyclic, electron-rich alkenes can also be performed using a [Pd0/Josiphos ligand] to obtain axially chiral heterobiaryl α-substituted alkenes in high yields and enantioselectivities. Products from Boc-protected 2,3-dihydropyrrole can be easily transformed into N,N ligands or appealing axially chiral, bifunctional proline-type organocatalysts. Computational studies suggest that a β-hydride elimination is the stereocontrolling step, in agreement with the observed stereochemical outcome of the reaction.Ministerio de Ciencia e Innovación (Grants CTQ2016-76908-C2-1-P; CTQ2016-76908-C2-2-P; CTQ2016-78083-P; RYC-2013-12585)European Commission (FEDER Programme)Junta de Andalucía (Grant 2012/FQM 10787)Universidad de Sevilla (Grant No. 1800511201)European Union - Marie Skłodowska-Curie (COFUND—Grant Agreement nº 291780

    Role of early experience in the development of preference for low-quality food in sheep

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    Domestic ruminant selectivity induces floristic changes in pasturelands, risking sustainability and limiting the subsequent availability of susceptible plant species. Development of preferences for species of lower nutritional quality may help to overcome those problems. In this study, we tested the hypothesis that early experience of sheep with a low-quality food (LQF) in a nutritional enriched context increases preference for LQF in adulthood. We predicted a higher proportional consumption of LQF in experienced lambs (EL) than in inexperienced lambs (IL) in choice situations involving LQF and alternative foods. Additionally, we determined intake of LQF by EL and IL at different levels of high-quality food (HQF) availability. From 60 to 210 days of age, EL were fed in separated feed bunks mature oat hay (LQF) simultaneously with sunflower meal (SM) and corn grain (CG), whereas IL were fed alfalfa hay (HQF) simultaneously with SM and CG. After exposure, EL and IL were offered LQF in free choice situations involving alternative foods, and also at five levels of HQF availability (100%, 75%, 50%, 25% and 0% of ad libitum intake). Proportional consumption of LQF was lower or similar in EL than IL. Intake of LQF was also lower or similar in EL than IL at all levels of HQF availability, except when the LQF was the only food available. Our results did not support the hypothesis that early experience with a LQF in a nutritional enriched context increases preference for LQF in adulthood. On the contrary, experience with LQF diminished subsequent preference for LQF in adulthood. It is proposed that, in the conditions of our study, continuous comparison between the LQF and the high-quality supplements (CG and SM) during the early exposure period lead to devaluation of LQF by EL through a simultaneous negative contrast effect.Fil: Catanese, Francisco Hernan. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Centro de Recursos Naturales Renovables de la Zona Semiárida. Universidad Nacional del Sur. Centro de Recursos Naturales Renovables de la Zona Semiárida; Argentina. Universidad Nacional del Sur. Departamento de Agronomía; ArgentinaFil: Distel, Roberto Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Centro de Recursos Naturales Renovables de la Zona Semiárida. Universidad Nacional del Sur. Centro de Recursos Naturales Renovables de la Zona Semiárida; Argentina. Universidad Nacional del Sur. Departamento de Agronomía; ArgentinaFil: Rodriguez Iglesias, R. M.. Universidad Nacional del Sur. Departamento de Agronomía; ArgentinaFil: Villalba, J. J.. State University of Utah; Estados Unido
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