Construction of plant transformation vectors carrying beet necrotic yellow vein virus coat protein gene (ii)- plant transformation

Fragments containing the coat protein gene of beet necrotic yellow vein virus were cloned in two plant transformation vectors: pCAMBIA3301M with the bar gene as selectable marker, and pCAMBIA1304M, with resistance to hygromycin. Three constructs were made of each vector: CPL, containing coat protein gene with leader sequence; CPS with coat protein gene, and CPSas with coat protein gene in antisense orientation. Vectors pC3301MCPL, pC3301MCPS. and pC3301MCPSas were used in Agrobacterium—mediated transformation of Nicotiana tabacum (tobacco), Nicotiana excelsior and Nicotiana benthamiana. Regenerants that developed roots on selective media were tested for the presence of CP fragments and the bar gene, but most regenerants were nontransformed (50-83% escapes). After all rooted plants had been selfed, and T1 seed germinated on selective media, only plants descending from one N. excelsior regenerant transformed with pC3301MCPS were positive for presence of bar gene and CPS fragment. Tobacco and Nicotiana benthamiana were transformed with constructs pC1304MCPS and pC1304MCPSas. Transformation efficiency was much higher and approximately 50% of regenerants that rooted on media with 20 mg l−1 hygromycin were positive for the presence of CP fragments. All T1 plants were positive for presence of CP fragments

Early Jurassic palaeoenvironments in the Surat Basin, Australia - marine incursion into eastern Gondwana

Interpretations of palaeodepositional environments are important for reconstructing Earth history. Only a few maps showing the Jurassic depositional environments in eastern Australia currently exist. Consequently, a detailed understanding of the setting of Australia in Gondwana is lacking. Core, wireline logs, two‐dimensional and three‐dimensional seismic from the Precipice Sandstone and Evergreen Formation in the Surat Basin have been used to construct maps showing the evolution of depositional environments through the Early Jurassic. The results indicate the succession consists of three third‐order sequences (Sequence 1 to Sequence 3) that were controlled by eustatic sea level. The lowstand systems tract in Sequence 1 comprises braidplain deposits, confined to a fairway that parallels the basin centre. The strata were initially deposited in two sub‐basins, with rivers flowing in different orientations in each sub‐basin. The transgressive systems tract of Sequence 1 to lowstand systems tract of Sequence 3 is dominated by fluvio–deltaic systems infilling a single merged basin centre. Finally, the transgressive and highstand systems tracts of Sequence 3 show nearshore environments depositing sediment into a shallow marine basin. In the youngest part of this interval, ironstone shoals are the most conspicuous facies, the thickness and number of which increase towards the north and east. This study interprets a corridor to the open ocean through the Clarence–Moreton Basin, or the Carpentaria and Papuan basins, evidence of which has been eroded. These results challenge a commonly held view that eastern Australia was not influenced by eustasy, and propose a more dynamic palaeogeographic setting comprising a mixture of fluvial, deltaic and shallow marine sedimentary environments. This work can be used to unravel the stratigraphic relationships between Mesozoic eastern Australian basins, or in other basins globally as an analogue for understanding the complex interplay of paralic depositional systems in data poor areas

Grain size, composition, porosity and permeability contrasts within cross-bedded sandstones in Tertiary fluvial deposits, central Spain

Permeability measured with a portable probe pcrmcflmeter on outcrops of cross·bcdded sandstones ranges betwecn 0·9 and 19 O. The highest pcrmeability (2-19 0 with an avcrage of8·5 D) occurs in thc coarsest grained foresct laminae (CFL). intermediate values (2-120 with an average of 5·3 D) occur in fincr grained foreset laminac (FFL) and thc lowest values (0·9-1 0 0 with un avcrage of 4·8 D) occur in boltomsct laycrs (BL). In the cross·bcds the uverage grain sizc rangcs from medium graincd sand in the CFL to finc grained s,lnd in thc FFL and BL. In all three subf'lcies. the average size of the primary pores is approximately It/> unit smaller than the averagc grain size. The abundance of unstablc carbonatc clasts correlatcs with incrcasing avcrage grain size, micritic clasts being most abundant in the CFL. Converscly. quartz content incrcascs with decreasing grain size and is highest in the FFL and BL. Oiagenetic destruction of primary porosity by compact ion and cementation. as well �IS generation of sccondary porosity through dissolution, were controlled by the original mineralogical composition of the sand. Contrasts in grain size detcrmine the primary pore size contrasts and differences in composition bctwecn CFL. FFL and BL. Permeability contrasts reflect variations in averagc primary pore size rather than differenccs in total porosity. Probe permeability contrasts between eFL. FFL and BL depend on contrasts in llverage pore size and contrasts in mineralogical composition between the subfacies

A model of discontinuous interest rate behavior, yield curves, and volatility

Interest rates, Yield curve, Levy process,