1,341 research outputs found

    High Energy Secondaries for the Quantitative Secondary Ion Mass Spectrometric Analysis of Minerals

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    The major hurdle in quantitative analysis by SIMS is the inconsistency and non-predictability of ion yields, particularly their sensitivity to sample matrix. High energy (100-500 eV) secondary ions have been shown to be considerably less susceptible to matrix effects than low energy secondary ions, particularly in mineral analysis. Therefore ion yields of some sixty elements were measured utilizing very high energy secondaries (~ 500 eV), from a standard silicate glass. They show a broad ionization potential dependence and a mass (or velocity) dependency which is not removed by the application of a M½ or M factor. The modification of yields with conventional thermodynamic partition functions, improves but does not clearly define agreement with the inverse exponential relationship observed by others, for low energy secondaries sputtered from oxygen rich matrices. The reproducibility of ion yields of high energy secondaries suggests empirical approaches to quantitative analysis are well justified; however the poor agreement of ion yields with an inverse exponential relationship, suggests that ion yielding mechanisms are somewhat different to those proposed in the low energy regime

    Sport fan attitudes on alcohol:Insights from a survey of football supporters in Scotland and England

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    Availability of alcohol at football matches in the UK is much debated and subject to multiple restrictions, yet there is little understanding of supporters’ attitudes. A cross-sectional survey of football supporters in Scotland and England (n  =  1750) was conducted April–June 2019. Most supporters viewed drinking at matches as acceptable (74.4%) and thought alcohol should be available at grounds (76.0%); around two-fifths thought most supporters consumed alcohol before matches (44.1%); but only a quarter (26.6%) thought disorder at matches was due to alcohol. Attitudes varied by supporter characteristics: supporters who were younger, in England, or more regular match-goers were more favourable towards alcohol consumption and availability at matches. We conclude that alcohol regulations in some nations and sports – where restrictions are based on historical disorder – may no longer be appropriate

    The rise of pinnacle reefs : a step change in marine evolution triggered by perturbation of the global carbon cycle

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    The first appearance of pinnacle reef tracts, composed of hundreds to thousands of localized biogenic structures protruding tens to hundreds of meters above the surrounding mid-Silurian seafloor, represents a step change in the evolution of the marine biosphere. This change in seafloor morphology opened a host of new ecological niches that served as "evolutionary cradles" for organism diversification. However, the exact timing and driver's of this event remain poorly understood. These uncertainties remain, in large part, due to a paucity of index fossils in the reef facies, the difficulty of correlating between the offshore pinnacle reefs and more temporally well-constrained shallow marine fades, and cryptic unconformities that separate amalgamated reefs. Here we use delta C-13(carb) stratigraphy within a sequence stratigraphic framework to unravel these complex relationships and constrain the origination of Silurian pinnacle reef tracts in the North American midcontinent to near the Pt. celloni Superzone-Pt. am. amorphognathoides Zonal Group boundary of the mid-Telychian Stage. In addition, we identify a striking relationship between pulses of reef development and changes in global delta C-13(carb) values and sea level. Viewed through this new perspective, we correlate prolific periods of reef development with short-lived carbon isotope (delta C-13(carb)) excursions and eustatic sea level change that, ultimately, reflect perturbations to the global carbon cycle. From changes in the dominance of microbial reefs of the Cambrian to metazoan colonization of reefs in the Middle Ordovician, through the subsequent collapse of metazoan diversity with the Late Ordovician mass extinction, and the first appearance of early Silurian (Llandovery) pinnacle reef tracts and their proliferation during the late Silurian (Wenlock-Pridoli) and Devonian, major reef formation intervals increasingly coincide with delta C-13(carb) excursions. These patterns suggest that Paleozoic reef evolution was the product of environmental forcing by perturbations of the global carbon cycle

    Stakeholder views of current laws surrounding alcohol at UK football matches:Is it a case of using a “sledgehammer to crack a nut”?

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    Background: In 2021, a fan-led review of football governance in England recommended that legislation surrounding alcohol and football be reviewed to determine whether it is still fit for purpose, the first such review since the mid-1980s. Restricting football fans’ alcohol consumption has been debated in the UK for over 40 years. However, more research is needed into the current attitudes of fans and influential stakeholders on this matter. Methods: Focus groups with football supporters (n=79) and semi-structured interviews (n=15) with key organisational stakeholders were conducted between November 2019 and February 2021. Focus groups included fans who regularly attended matches and supported various teams from professional leagues in Scotland and England, casual fans who usually watched games at home or in bars, and fans who followed the Scotland and England national teams. Stakeholders were selected to represent organisations likely to be instrumental in any regulatory change, such as the UK and Scottish Governments, Police, football supporters’ groups and safety organisations. Results: The current law does not allow for alcohol to be consumed within view of the pitch. Participants from England suggested this could be changed. While in Scotland, where the legislation only allows alcohol to be sold in hospitality, most participants were in favour of allowing the general sale of alcohol at football stadia via a pilot scheme. The reasons for these changes included: reducing unhealthy drinking behaviours; minimising the health and safety risk of fans arriving at the stadium just before kick-off; and a potential increase in much needed revenue for clubs. Conclusion: Our data suggests an evidence-based review of current laws regarding alcohol and football may be appropriate. However, any discussion regarding changes to the law regarding alcohol at football stadia, including potential pilot schemes, should be evaluated and monitored in terms of both financial impact and the impact on public health and safety

    Seedling development traits in Brassica napus examined by gene expression analysis and association mapping

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    BACKGROUND: An optimal seedling development of Brassica napus plants leads to a higher yield stability even under suboptimal growing conditions and has therefore a high importance for plant breeders. The objectives of our study were to (i) examine the expression levels of candidate genes in seedling leaves of B. napus and correlate these with seedling development as well as (ii) detect genome regions associated with gene expression levels and seedling development traits in B. napus by genome-wide association mapping. RESULTS: The expression levels of the 15 candidate genes examined in the 509 B. napus inbreds showed an averaged standard deviation of 5.6 across all inbreds and ranged from 3.2 to 8.8. The gene expression differences between the 509 B. napus inbreds were more than adequate for the correlation with phenotypic variation of seedling development. The average of the absolute value correlations of the correlation coefficients of 0.11 were observed with a range from 0.00 to 0.39. The candidate genes GER1, AILP1, PECT, and FBP were strongly correlated with the seedling development traits. In a genome-wide association study, we detected a total of 63 associations between single nucleotide polymorphisms (SNPs) and the seedling development traits and 31 SNP-gene associations for the candidate genes with a P-value < 0.0001. For the projected leaf area traits we identified five different association hot spots on the chromosomes A2, A7, C3, C6, and C7. CONCLUSION: A total of 99.4% of the adjacent SNPs on the A genome and 93.0% of the adjacent SNPs on the C genome had a distance smaller than the average range of linkage disequilibrium. Therefore, this genome-wide association study is expected to result on average in 14.7% of the possible power. Compared to previous studies in B. napus, the SNP marker density of our study is expected to provide a higher power to detect SNP-trait/-gene associations in the B. napus diversity set. The large number of associations detected for the examined 14 seedling development traits indicated that these are genetically complex inherited. The results of our analyses suggested that the studied genes ribulose 1,5-bisphosphate carboxylase/oxygenase small subunit (RBC) on the chromosomes A4 and C4 and fructose-1,6-bisphosphatase precursor (FBP) on the chromosomes A9 and C8 are cis-regulated. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s12870-015-0496-3) contains supplementary material, which is available to authorized users

    Cucurbit[n]uril binding of platinum anticancer complexes

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    The encapsulation of cisplatin by cucurbit[7]uril (Q[7]) and multinuclear platinum complexes linked via a 4,4′-dipyrazolylmethane (dpzm) ligand by Q[7] and cucurbit[8]uril (Q[8]) has been studied by NMR spectroscopy and molecular modelling. The NMR studies suggest that some cisplatin binds in the cucurbituril cavity, while cis-[PtCl(NH3)2(H2O)]+ only binds at the portals. Alternatively, the dpzm-linked multinuclear platinum complexes are quantitatively encapsulated within the cavities of both Q[7] and Q[8]. Upon encapsulation, the non-exchangeable proton resonances of the multinuclear platinum complexes show significant upfield shifts in 1H NMR spectra. The H3/H3* resonances shift upfield by 0.08 to 0.55 ppm, the H5/H5* shift by 0.9 to 1.6 ppm, while the methylene resonances shift by 0.74 to 0.88 ppm. The size of the resonance shift is dependent on the cavity size of the encapsulating cucurbituril, with Q[7] encapsulation producing larger shifts than Q[8]. The upfield shifts of the dpzm resonances observed upon cucurbituril encapsulation indicate that the Q[7] or Q[8] is positioned directly over the dpzm linking ligand. The terminal platinum groups of trans-[{PtCl(NH3)2}2μ-dpzm]2+ (di-Pt) and trans-[trans-{PtCl(NH3)2}2-trans-{Pt(dpzm)2(NH3)2}]4+ (tri-Pt) provide a barrier to the on and off movement of cucurbituril, resulting in binding kinetics that are slow on the NMR timescale for the metal complex. Although the dpzm ligand has relatively few rotamers, encapsulation by the larger Q[8] resulted in a more compact di-Pt conformation with each platinum centre retracted further into each Q[8] portal. Encapsulation of the hydrolysed forms of di-Pt and tri-Pt is considerably slower than for the corresponding Cl forms, presumably due to the high-energy cost of passing the +2 platinum centres through the cucurbituril portals. The results of this study suggest that cucurbiturils could be suitable hosts for the pharmacological delivery of multinuclear platinum complexe

    Oleaginous crops as integrated production platforms for food, feed, fuel and renewable industrial feedstock

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    The world faces considerable challenges including how to produce more biomass for food, feed, fuel and industrial feedstock without significantly impacting on our environment or increasing our consumption of limited resources such as water or petroleum-derived carbon. This has been described as sustainable intensification. Oleaginous crops have the potential to provide renewable resources for all these commodities, provided they can be engineered to meet end-use requirements, and that they can be produced on sufficient scale to meet current growing world population and industrial demand. Although traditional breeding methods have been used successfully to modify the fatty acid composition of oils, metabolic engineering provides a more rapid and direct method for manipulating plant lipid composition. Recent advances in our understanding of the biochemical mechanisms of seed oil biogenesis and the cloning of genes involved in fatty acid and oil metabolic pathways, have allowed the generation of oilseed crops that produce ‘designer oils’ tailored for specific applications and the conversion of high biomass crops into novel oleaginous crops. However, improvement of complex quantitative traits in oilseed crops remains more challenging as the underlying genetic determinants are still poorly understood. Technological advances in sequencing and computing have allowed the development of an association genetics method applicable to crops with complex genomes. Associative transcriptomics approaches and high throughput lipidomic profiling can be used to identify the genetic components controlling quantitative variation for lipid related traits in polyploid crops like oilseed rape and provide molecular tools for marker assisted breeding. In this review we are citing examples of traits with potential for bio-refining that can be harvested as co-products in seeds, but also in non-harvested biomass
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