Search results for "blocks"
showing 10 items of 23 documents
Representations of finite groups: Blocks relative to a normal subgroup
2019
Algunes de les principals conjectures en Teoria de Representacions de Grups Finits admeten refinaments en termes de p-blocs de Brauer. Actualment només es veu un camí per a atacar aquest tipus de conjectures: reduir-les a problemes de grups simples i utilitzar la Classificació dels Grups Finits Simples per a resoldre-les. Entenem per reduir a un problema de grups simples que el problema té solució sempre que es comproven una sèrie de condicions per a tots els grups finits simples. Per descomptat, els subgrups normals (i els seus caracters irreductibles) juguen un paper fonamental en aquest procés. Una de las tècniques principals utilitzades en la reducció de certs problemes de teoria de car…
Ring splitting of azetidin-2-ones via radical anions
2012
The radical anions of azetidin-2-ones, generated by UV-irradiation in the presence of triethylamine, undergo ring-splitting via N-C4 or C3-C4 bond breaking, leading to open-chain amides. This reactivity diverges from that found for the neutral excited states, which is characterised by alpha-cleavage. The preference for beta-cleavage is supported by DFT theoretical calculations on the energy barriers associated with the involved transition states. Thus, injection of one electron into the azetidin-2-one moiety constitutes a complementary activation strategy which may be exploited to produce new chemistry.
Synthesis of the new ring system 6,8-dihydro-5H-pyrrolo[3,4-h]quinazoline
2009
Abstract A convenient synthesis of the pyrrolo[3,4- h ]quinazoline ring system is reported. Our synthetic approach consisted of the annelation of a pyrimidine ring to an isoindole moiety using tetrahydroisoindole-4-ones as building blocks. The antiproliferative activity of the new compounds was investigated and one of them showed antitumor activity against all the 59 tested cell lines at micromolar concentrations (1.46–18.4 μM).
Integrating miniMin-HSP agents in a dynamic simulation framework
2004
In this paper, we describe the framework created for implementing AI-based animations for artificial actors in the context of IVE (Intelligent Virtual Environments). The minMin-HSP (Heuristic Search Planner) planner presented in [12] has been updated to deal with 3D dynamic simulation environments, using the sensory/actuator system fully implemented in UnrealTM and presented in [10]. Here, we show how we have integrated these systems to handle the necessary balance between the reactive and deliberative skills for 3D Intelligent Virtual Agents (3DIVAs). We have carried out experiments in a multi-agent 3D blocks world, where 3DIVAs will have to interleave sensing, planning and execution to be…
Efficient microwave-assisted synthesis of glycerol monodecanoate
2017
International audience; Solvent-free microwave-assisted synthesis was carried out to prepare 2,3-dihydroxypropyl decanoate, by esterification of decanoic acid in the presence of two distinct glycerol derivatives, glycidol, and glycerol carbonate, respectively. The process described is based on microwaves heating source with electrical power in the range of 200–400 W, involving stoichiometric proportions of decanoic acid and glycerol derivatives, and using catalytic amounts of TBAI used as organocatalyst. Conversion and selectivity rates of esterification reactions were monitored by 1H and 13C{1H} NMR spectroscopy. The predominantly formed ester, 2,3-dihydroxypropyl decanoate was fully chara…
Structure and function of the vacuolar Ccc1/VIT1 family of iron transporters and its regulation in fungi
2020
Iron is an essential micronutrient for most living beings since it participates as a redox active cofactor in many biological processes including cellular respiration, lipid biosynthesis, DNA replication and repair, and ribosome biogenesis and recycling. However, when present in excess, iron can participate in Fenton reactions and generate reactive oxygen species that damage cells at the level of proteins, lipids and nucleic acids. Organisms have developed different molecular strategies to protect themselves against the harmful effects of high concentrations of iron. In the case of fungi and plants, detoxification mainly occurs by importing cytosolic iron into the vacuole through the Ccc1/V…
Rinnakkaislaskentamallien arviointi : Intel Threading Building Blocks
2013
Moniydinprosessoreiden ollessa jo normi on rinnakkaislaskennasta tullut arkipäivää yhä useammalle ohjelmoijalle. Rinnakkaislaskenta on hankalaa hahmottaa ja toteuttaa, joten tarvitaan uusia korkeamman abstraktiotason rinnakkaislaskentamalleja tukemaan rinnakkaislaskennan yleistymistä. Tässä tutkielmassa luomme mallin rinnakkaislaskentamallien arviointiin kahdeksasta eri näkökulmasta. Sen jälkeen tutustumme Intel Threading Building Blocks (TBB) -rinnakkaistuskirjastoon, joka lupaa tehdä rinnakkaislaskennan toteuttamisesta helpompaa siirtämällä rinnakkaistuksen perusmekanismeja pois ohjelmoijan vastuulta. Lopuksi arvioimme TBB:tä aiemmin luomamme mallin pohjalta. Toteamme, että TBB täyttää hy…
Isolation and Characterization of High-Efficiency Rhizobia From Western Kenya Nodulating With Common Bean.
2021
Common bean is one of the primary protein sources in third-world countries. They form nodules with nitrogen-fixing rhizobia, which have to be adapted to the local soils. Commercial rhizobial strains such as Rhizobium tropici CIAT899 are often used in agriculture. However, this strain failed to significantly increase the common bean yield in many places, including Kenya, due to the local soils’ low pH. We isolated two indigenous rhizobial strains from the nodules of common bean from two fields in Western Kenya that have never been exposed to commercial inocula. We then determined their ability to fix nitrogen in common beans, solubilize phosphorus, and produce indole acetic acid. In greenhou…
Direct catalytic cross-coupling of alkenyllithium compounds
2015
A catalytic method for the direct cross-coupling of alkenyllithium reagents with aryl and alkenyl halides is described. The use of a catalyst comprising Pd-2(dba)(3)/XPhos allows for the stereoselective preparation of a wide variety of substituted alkenes in high yields under mild conditions. In addition (1-ethoxyvinyl) lithium can be efficiently converted into substituted vinyl ethers which, after hydrolysis, give readily access to the corresponding methyl ketones in a one pot procedure.
The neurobiological bases for the pharmacotherapy of nicotine addiction.
2007
Nicotine, the major psychoactive agent present in tobacco, acts as a potent addictive drug both in humans and laboratory animals, whose locomotor activity is also stimulated. A large body of evidence indicates that the locomotor activation and the reinforcing effects of nicotine may be related to its stimulatory effects on the mesolimbic dopaminergic function. Thus, it is now well established that nicotine can increase in vivo DA outflow in the nucleus accumbens and the corpus striatum. The stimulatory effect of nicotine on DA release most probably results from its ability to excite the neuronal firing rate and to increase the bursting activity of DA neurons in the substantia nigra pars com…