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81.
84.
Abstract This study surveys the population genetic structure of Childers canegrub, Antitrogus parvulus , to elucidate its population dynamics and gene flow. Antitrogus parvulus is a pest of sugarcane in the Bundaberg region and this knowledge can be used to optimise integrated pest management practices. Here, base-pair differences in the cytochrome oxidase II gene ( COII ) were used to characterise haplotypic diversity, infer levels of gene flow, and phylogenetic relationships of alleles and their phylogeographical structure. There were 28 unique haplotypes among the 70 sequenced individuals from the seven locations. All three variance components (among regions, among populations, within populations) are highly significant, with highest genetic diversity among regions and lowest among populations within regions. A positive correlation between migration rates and geographical distance and significant phylogeographical structure between four main geographical regions. The main implication of these findings for pest management is that if a grower can eliminate an existing infestation within a field, then reinvasion will be slow and further outbreaks within that field are unlikely to occur. The low dispersal ability of females also means that any resistance to insecticides that develops is likely to remain localised, but will rapidly become dominant within the affected population. 相似文献
85.
Sarah L. Shammas Michael D. Crabtree Liza Dahal Basile I. M. Wicky Jane Clarke 《The Journal of biological chemistry》2016,291(13):6689-6695
Intrinsically disordered proteins (IDPs) are characterized by a lack of persistent structure. Since their identification more than a decade ago, many questions regarding their functional relevance and interaction mechanisms remain unanswered. Although most experiments have taken equilibrium and structural perspectives, fewer studies have investigated the kinetics of their interactions. Here we review and highlight the type of information that can be gained from kinetic studies. In particular, we show how kinetic studies of coupled folding and binding reactions, an important class of signaling event, are needed to determine mechanisms. 相似文献
86.
A genome-wide screen for modifiers of transgene variegation identifies genes with critical roles in development 下载免费PDF全文
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88.
Researchers can have unintentional, yet significant effects on their study systems. We tested for the effects of an intensive
tree census on seedling dynamics in a 50-ha permanent forest plot on Barro Colorado Island, Panama. At the community level,
and for different shade-tolerance guilds, we found no significant differences in seedling recruitment or survival inside compared
to controls outside the plot. However, among growth forms, canopy trees and lianas exhibited significantly lower seedling
survival inside the plot. Results suggest that intense researcher activity impacts short-term vegetation dynamics, but effects
do not accumulate over time. 相似文献
89.
Kate R. O’Brien Julien Ménaché Liza M. O’Moore 《The International Journal of Life Cycle Assessment》2009,14(7):621-629
Background, aim and scope
Fly ash, a by-product of coal-fired power stations, is substituted for Portland cement to improve the properties of concrete and reduce the embodied greenhouse gas (GHG) emissions. Much of the world’s fly ash is currently disposed of as a waste product. While replacing some Portland cement with fly ash can reduce production costs and the embodied emissions of concrete, the relationship between fly ash content and embodied GHG emissions in concrete has not been quantified. The impact of fly ash content on embodied water is also unknown. Furthermore, it is not known whether a global trade in fly ash for use in concrete is feasible from a carbon balance perspective, or if transport over long distances would eliminate any CO2 savings. This paper aims to quantify GHG emissions and water embodied in concrete (f′c = 32 MPa) as a function of fly ash content and to determine the critical fly ash transportation distance, beyond which use of fly ash in concrete increases embodied GHG emissions. 相似文献90.
James D. Swarbrick Liza Cubeddu Graham E. Ball Paul M. G. Curmi Andrew A. Gooley Keith L. Williams Bridget C. Mabbutt 《Biomolecular NMR assignments》2009,3(1):1-3
Presopore-specific antigen (PsA) is a cell surface glycoprotein of the cellular slime mould Dictyostelium discoidum implicated in cell adhesion. The 15N, 13C and 1H chemical shift assignments of PsA were determined from multidimensional, multinuclear NMR experiments. Resonance assignments
have been made for both the N-terminal globular domain and its attached O-glycosylated PTVT linker motif. 相似文献