1,748 research outputs found
Avis DeVoto, George Homans, Al Delacey at a picnic on Lake Memphremagog, Quebec.
No full textScan of a black and white photograph of (l. to r.) Avis DeVoto, George Homans, and Al Delacey enjoying a picnic among the trees at Lake Memphremagog, Quebec in 1931
Avis DeVoto with her young children Mark and Gordon DeVoto.
No full textScan of a black and white photograph of the young sons and wife of Bernard DeVoto (l. to r.) Gordon DeVoto, Mark DeVoto, and Avis DeVoto, their mother, on a blanket that is on a lawn
Una revisión de la evidencia de la dependencia de la soja [Glycine max (L.) Merr.] de la polinización por insectos
No full textLa comprensión de los servicios ecosistémicos, con toda la complejidad que implica, es necesaria para un manejo adecuado de los ecosistemas, y los científicos deben generar esa información para que sea utilizada en la toma de decisiones. Las recomendaciones de manejo se basan en evidencia científica que puede ser de calidad variable. La importancia de la polinización de cultivos es un ejemplo de un servicio ecosistémico para el cual se ha acumulado un volumen de evidencia creciente. En particular para soja hay varios trabajos que sugieren que el rendimiento del cultivo depende de la acción de polinizadores. Sin embargo, esto contradice lo que tradicionalmente se asume del cultivo. En este contexto, es necesario revisar críticamente la evidencia disponible para decidir si es necesario un cambio en las recomendaciones de manejo del servicio de polinización de este cultivo.Fil: Palacios, Tania Paula. Universidad de Buenos Aires. Facultad de Agronomía. Cátedra de Botánica General; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Devoto, Mariano. Universidad de Buenos Aires. Facultad de Agronomía. Cátedra de Botánica General; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaPrimera reunión de la red de investigadores en biología de la polinización de ArgentinaCiudad Autónoma de Buenos AiresArgentinaUniversidad de Buenos Aires. Facultad de Agronomí
Estudio del caso Fandango como intermediario digital de la industria audiovisual argentina : ¿innovación o thriller?
No full textFil: Devoto Borrelli, María C.. Universidad de San Andrés. Departamento de Derecho; Argentina
Avis DeVoto and Robert Frost at the Bread Loaf School of English.
No full textScan of a black and white photograph of Avis DeVoto and Robert Frost sitting on a porch on the site of the Bread Loaf School of English at Middlebury College in Vermont. Avis DeVoto is the wife of author Bernard DeVoto
Why is the cystic fibrosis gene so frequent?
No full textThe high incidence of cystic fibrosis (CF) in most European populations (and populations of European descent) can be explained by different hypotheses that can be tested using the available data concerning this disorder. Among the five hypotheses discussed (genetic heterogeneity, high rate of mutation, meiotic drive, drift and heterozygote advantage), only the last is supported by experimental data. The following conclusions can be drawn from the evidence that we have reviewed: (1) CF is a single gene disorder (genetically homogeneous). (2) Haplotypes associated with the CF gene suggest that only a few mutations (the same gene located in 7q13 is always affected) are responsible for the disorder. (3) CF with pancreatic insufficiency is mainly associated with a single haplotype, whereas CF with pancreatic sufficiency is more frequently associated with different haplotypes. (4) A selective advantage consisting of higher resistance to Cl- -secreting diarrhoeas might have favored, in the past, survival of infants heterozygous for the CF gene
Evidence for co-release of noradrenaline and dopamine from noradrenergic neurons in the cerebral cortex
No full textThe aim of this study was to determine whether extracellular dopamine (DA) in the prefrontal cortex (PFC) might originate other than from DA neurons, also from noradrenergic (NA) ones. To this aim, we compared the levels of DA and NA in the dialysates from the PFC, a cortical area innervated by NA and DA neurons, and cortices that receive NA but minor or no DA projections such as the primary motor, the occipital-retrosplenial, and the cerebellar cortex. Moreover, the effect of α2-ligands and D2-ligands that distinctly modify NA and DA neuronal activity on extracellular NA and DA in these areas was studied. Extracellular NA concentrations were found to be similar in the different cortices, as expected from the homogeneous NA innervation, however, unexpectedly, also DA concentrations in the PFC were not significantly different from those in the other cortices. The α2-adrenoceptor agonist clonidine, intraperitoneally (i.p.) injected or locally perfused into the PFC, reduced not only extracellular NA levels, as expected from its ability to inhibit NA neuron activity, but also markedly reduced extracellular DA levels. Conversely, the α2-adrenoceptor antagonist idazoxan, i.p. injected or locally perfused into the PFC, not only increased extracellular NA levels, in line with its ability to activate NA neuron activity, but also increased those of DA. Conversely, in contrast to its ability to inhibit DA neuronal activity, the D2 receptor agonist quinpirole only modestly and transiently reduced extracellular DA levels, while γ-butyrolactone failed to modify DA levels in the PFC; conversely, haloperidol, at variance from its ability to activate DA neurons, failed to significantly modify extracellular DA levels in the PFC. Both haloperidol and quinpirole were totally ineffective after local perfusion into the PFC. Systemically injected or locally perfused, clonidine and idazoxan also modified both DA and NA concentrations in dialysates from primary motor, occipital-retrosplenial and cerebellar cortices as observed in the PFC. Finally, i.p. injected or locally perfused, clonidine reduced and idazoxan increased extracellular NA levels in the caudate nucleus, but neither α2-ligand significantly modified extracellular DA levels. Our results suggest that extracellular DA in the PFC, as well as in the other cortices, may depend on NA rather than DA innervation and activity. They suggest that dialysate DA reflects the amine released from NA neurons as well, where DA acts not only as NA precursor but also as co-transmitter. The co-release of NA and DA seems to be controlled by α2-receptors located on NA nerve terminals
Inhibition of [3H] dopamine uptake by flunarizine
No full textThe effect of different calcium channel blockers was studied on basal and cocaine-inhibited [3H]dopamine uptake in rat striatal synaptosomes. Isradipine (dihydropyridine calcium antagonist) and diltiazem (L-type calcium antagonist) were devoid of effect on [3H]dopamine uptake, while flunarizine (T-type calcium antagonist) inhibited [3H]dopamine uptake. Flunarizine inhibition was competitive and the inhibitory curve was biphasic with a Hill coefficient of 2.1. The high Hill number suggested a mechanism of positive cooperativity between two sites. Flunarizine inhibition showed a complex interaction with cocaine inhibition. While flunarizine at low concentrations interacts with a distinct site, at higher concentrations it interacts with the same site as cocaine. The relevance of this finding for the potentiation by flunarizine of cocaine-induced dopamine release in vivo is discussed
Inhibition of [3H]dopamine uptake by flunarizine
No full textThe effect of different calcium channel blockers was studied on basal and cocaine-inhibited [3H]dopamine uptake in rat striatal synaptosomes. Isradipine (dihydropyridine calcium antagonist) and diltiazem (L-type calaium antagonist) were devoid of effect on [3H]dopamine uptake, while flunarizine (T-type calcium antagonist) inhibited [3H]dopamine uptake. Flunarizine inhibition was competitive and the inhibitory curve was biphasic with a Hill coefficient of 2.1. The high Hill number suggested a mechanism of positive cooperativity between two sites. Flunarizine inhibition showed a complex interaction with cocaine inhibition. While flunarizine at low concentrations interacts with a distinct site, at higher concentrations it interacts with the same site as cocaine. The relevance of this finding for the potentiation by flunarizine of cocaine-induced dopamine release in vivo is discussed. © 1991
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