Capim corrente: opção para criação animal a pasto no semiárido.

bitstream/item/115055/1/midia-Capim.pd

k-deformed Poincare algebras and quantum Clifford-Hopf algebras

The Minkowski spacetime quantum Clifford algebra structure associated with the conformal group and the Clifford-Hopf alternative k-deformed quantum Poincare algebra is investigated in the Atiyah-Bott-Shapiro mod 8 theorem context. The resulting algebra is equivalent to the deformed anti-de Sitter algebra U_q(so(3,2)), when the associated Clifford-Hopf algebra is taken into account, together with the associated quantum Clifford algebra and a (not braided) deformation of the periodicity Atiyah-Bott-Shapiro theorem.Comment: 10 pages, RevTeX, one Section and references added, improved content

Protocolo para desinsfestação de explantes foliares de Cissus verticillata (L) Nicolson & C. E. Jarvis para estabelecimento in vitro.

Este trabalho teve como objetivo avaliar diferentes tratamentos de desinfestação de explantes foliares de C.verticillata para o seu estabelecimento in vitro. A pré-limpeza consistiu na lavagem das folhas com esponja e água destilada com algumas gotas de detergente comercial

Calogênese em insulina vegetal (Cissus verticillata(L.) Nicolson & C. E. Jarvis).

O objetivo foi desenvolver um protocolo para a indução de calos em explantes foliares de Cissus verticillata (L.) Nicolson & C. E. Jarvis e quantificar a massa fresca obtida visando à produção de metabólitos secundários

Calogênese em explantes de foliares de pupunheira (Bactris gasipaes H.B.K.) submetidos a meio de cultivo com diferentes níveis de PH.

O objetivo deste trabalho foi desenvolver protocolos para indução de calos em explantes foliares de B. gasipaes submetidos a diferentes níveis de pH do meio de cultivo em combinações fatoriais com 2,4-D

Shelf-Ocean material exchange influencing the Atlantic chemical composition off NW Iberian margin since the last glaciation

Rivers are the main conduit of sediment to the shelf. The basin geology, the drainage area and the discharge rate are the major factors that determine their sediment load (Milliman and Syvistski, 1992). Besides suspended particles, dissolved components may also give some information on the eroded crust. Sr isotopes in carbonate shells of biological organisms have been used to study, in the geological record, the influence exerted by the chemical weathering of the continental crust on the seawater composition (Macdougall, 1991). In this work, Sr isotope ratios obtained in tests of foraminifera representing the last 40 ka are presented and discussed in the scope of the palaeogeographical evolution of NW Iberia. This work aims to present and discuss the results of Sr isotope analyses (performed, by TIMS, in the Isotope Geology Laboratory of the University of Aveiro) of tests of two species of foraminifera, from nine samples taken along the OMEX core KC 024-19 (181 cm; 42°08’98’’N, 10°29´96’’W, and 2765m), collected in the Galicia Bank area, off Galicia. Taking into account that Sr contained in the carbonate tests is usually considered as preserving the signature of the contemporaneous seawater, one planktonic species (Globigerina bulloides) and one benthic species (Cibicides wuellerstorfi) were selected in order to try to detect Sr isotope variations both through time and between two different levels of the water column. The core age model, which records the last 40 ka, is based on a combination of oxygen isotope stratigraphy, eight AMS 14C datings and the synchronisation of the last four Heinrich Events in the Iberian Margin sedimentary records. As a whole, the obtained 87Sr/86Sr ratios vary between 0.709209 and 0.709108, with a mean 2σ error of 0.000025. These values lie within the range of modern marine Sr isotope ratios (0.70910-0.70922), as previously defined using analyses of both seawater and marine carbonates (see compilation by Faure and Mensing, 2005). Despite their small variation, the 87Sr/86Sr ratios obtained in G. bulloides seem to indicate that Sr dissolved in seawater at the KC 024-19 core site became slightly less radiogenic after the Last Glacial Maximum (LGM). This decrease is concomitant with diminishing amounts of the detrital components in the sediments (Fig. 1). Therefore, both the composition of dissolved Sr, as revealed by results on tests of planktonic foraminifera, and the proportions of suspended terrigenous particulate material arriving at the KC 024-19 site point to a decreasing importance of the contribution of the erosion of the Iberian Variscan crust since the Last Glacial Maximum and in the Holocene. The 87Sr/86Sr ratios measured in tests of benthic foraminifera (C. wuellerstorfi) are more erratic and no correlation can be established with palaeogeographical/palaeoclimatic constraints. The difference between the behaviour of Sr compositions in G. bulloides and C. wuellerstorfi may indicate that whilst the planktonic foraminifera should reproduce very closely the seawater composition, the benthic organisms should, in addition to the major role of seawater, also be affected by some sort of interaction with the sediments. As such, planktonic foraminifera are probably more reliable indicators of seawater composition in studies involving very small periods and corresponding very slight variations of the 87Sr/86Sr ratios. Taking into account that G. bulloides is a common planktonic species (living mostly in the first 50m of the water column), whose tests seem to be in equilibrium with sea water composition, variations in its 87Sr/86Sr ratios can be related with changes in the chemical composition of the water of the Atlantic Ocean off NW Iberian Margin. The highest 87Sr/86Sr values are contemporaneous with a period of low sea level (about -140 m; Dias et al., 2000) during the LGM. According to Dias et al. (2000) at 18 ka BP the shoreline was close to the shelf break. The summital parts of the Gerês and Estrela mountains were covered by local glaciers and close to the coast freezing occurred frequently. The river catchments, which extended far to the shelf, received more rainfall due to a longer, compared to present day conditions, wet season, which promoted both physical and chemical weathering. Higher pluviosity combined with the effect of spring ice melting maintained high river discharge and consequently caused very important sediment supply to the coastal zone. The extremely narrow shelf was a very energetic environment due to sea bottom inclination and very limited long wave refraction. Therefore, at that time, a long wet season and very competent rivers should have caused important erosion of the Variscan basement in NW Iberia. Additionally, then, the shoreline was much closer to the KC 024-19 site. The combination of all these factors favoured an important deposition of terrigenous sediments and the local slight enrichment in radiogenic Sr of the seawater. With sea level rise, after the deglaciation and during the Holocene, the river estuaries became progressively far away from the shelf break. Their competence of transport also became progressively reduced and the offshore transport of detrital sediments became progressively lower. Conversely the biogenic carbonate proportion in the sediments increased, due to lower dilution by the terrigenous particles. Simultaneously, the values of 87Sr/86Sr in the seawater at the KC 024-19 site became lower, as a consequence of a complete homogenization with the ocean global composition, which was now more effective with the increasing distance towards shoreline

Calogênese em explantes foliares de pupunheira (Bactris gasipaes H.B.K.) submetidos a diferentes concentrações de nitrato de amônio.

O objetivo deste trabalho foi desenvolver protocolos para indução de calos em explantes foliares de B. gasipaes submetidos a diferentes concentrações de nitrato de amônio em combinação fatorial com 2,4-D

Leucena.

O que é? Para que serve? Como plantar? Como manejar? Quais as vantagens? Quais os cuidados.bitstream/item/119851/1/CNPC-2014-Leucena.pd

Palma forrageira no Nordeste do Brasil: estado da arte.

bitstream/item/96744/1/DOC-106.pd

Melhoramento vegetal e recursos genéticos forrageiros.

A criação animal no Brasil é predominantemente extensiva em pastos cultivados ou nativos a depender da região. No semiárido a limitação de precipitação pluviométrica dificulta a manutenção de pastos cultivados, e a dependência pela vegetação nativa se torna maior. Embora exista inúmeras opções de gramíneas e leguminosas forrageiras que podem enriquecer a pastagem nativa, na região semiárida as opções disponíveis nos mercados formais são restritas e muitas vezes as sementes comercializadas não são validadas para a região. Para disponibilizar aos produtores forrageiras adaptadas às condições de manejo e clima, programas de melhoramento genético de forrageiras devem avaliar os acessos presentes em Banco Ativo de Germoplasma da Embrapa e de instituições parceiras para identificar material que produza em condições de estresse hídrico. Pela diversidade de espécies passíveis de melhoramento, as redes de pesquisa devem concentrar esforços em coleções representativas da diversidade, com histórico de adoção pelos produtores e que atendam a mais de um sistema de produção. Assim, a pesquisa será capaz de ofertar soluções em diferentes marcos temporais.O mercado está ávido por plantas mais resistentes à seca, considerando que as mudanças climáticas demandarão mais opções de plantas tolerantes a falta de água. Além disso, há uma crescente expansão da pecuária para a região Nordeste. Este documento reúne, em sua primeira parte, o estado da arte do melhoramento genético forrageiro no semiárido com as principais espécies gramíneas e leguminosas. A segunda parte se dedica aos recursos genéticos forrageiros armazenados em bancos ativos de germoplasma da Embrapa nas diferentes unidades da federação, mostrando a importância da conservação da formação de redes de pesquisa e uso desses materiais para a pesquisa agropecuária nacional e mundial.bitstream/item/117062/1/CNPC-2014-Melhoramento.pd