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11.
We present the first assessment of the impact of land use change (LUC) to second‐generation (2G) bioenergy crops on ecosystem services (ES) resolved spatially for Great Britain (GB). A systematic approach was used to assess available evidence on the impacts of LUC from arable, semi‐improved grassland or woodland/forest, to 2G bioenergy crops, for which a quantitative ‘threat matrix’ was developed. The threat matrix was used to estimate potential impacts of transitions to either Miscanthus, short‐rotation coppice (SRC, willow and poplar) or short‐rotation forestry (SRF). The ES effects were found to be largely dependent on previous land uses rather than the choice of 2G crop when assessing the technical potential of available biomass with a transition from arable crops resulting in the most positive effect on ES. Combining these data with constraint masks and available land for SRC and Miscanthus (SRF omitted from this stage due to lack of data), south‐west and north‐west England were identified as areas where Miscanthus and SRC could be grown, respectively, with favourable combinations of economic viability, carbon sequestration, high yield and positive ES benefits. This study also suggests that not all prospective planting of Miscanthus and SRC can be allocated to agricultural land class (ALC) ALC 3 and ALC 4 and suitable areas of ALC 5 are only minimally available. Beneficial impacts were found on 146 583 and 71 890 ha when planting Miscanthus or SRC, respectively, under baseline planting conditions rising to 293 247 and 91 318 ha, respectively, under 2020 planting scenarios. The results provide an insight into the interplay between land availability, original land uses, bioenergy crop type and yield in determining overall positive or negative impacts of bioenergy cropping on ecosystems services and go some way towards developing a framework for quantifying wider ES impacts of this important LUC.  相似文献   
12.
The digestive tract of elephants is surprisingly short compared to other herbivorous mammals. However, measurements relating the length of the intestine to the body mass of the respective individual are rare. In this study, we report such data for an African elephant and an Asian elephant. Our data support the hypothesis that Asian elephants have a longer intestinal tract than their African counterparts. These findings are in accord with the observation of longer retention times and higher digestion coefficients in Asian as compared to African elephants. This difference between the species could be the reflection of slightly different ecological niches, with Asian elephants adapted to a natural diet with a higher proportion of grass.  相似文献   
13.
Avian species have developed a range of markers for transmitting information, among them ornamented plumage, behavioural patterns and conspicuous bill structures. Members of the marine subfamily Fraterculinae have some of the most visibly noticeable ornaments among seabirds, and some species have been recently found to possess fluorescent properties in seasonally acquired bill plates. We examined a member of this subfamily, the Rhinoceros Auklet Cerorhinca monocerata, for fluorescence in the upper and lower mandibles as well as the namesake horn grown in preparation for mate selection. Fluorescence was noted primarily in the horn of adults, with greater variation present among individuals than between the sexes.  相似文献   
14.
A series of 11-oxa prostaglandin analogs was evaluated for FP receptor binding and activation. Several compounds having aryloxy-terminated lower chains were found to be potent agonists. Topical ocular dosing of AL-12182, the isopropyl ester prodrug of the potent agonist 13, lowered intraocular pressure in the monkey by 40% accompanied by minimal conjunctival hyperemia in the rabbit. AL-12182 was synthesized on multigram scale starting with D-sorbitol.  相似文献   
15.
We present an ontology for describing genomes, genome comparisons, their evolution and biological function. This ontology will support the development of novel genome comparison algorithms and aid the community in discussing genomic evolution. It provides a framework for communication about comparative genomics, and a basis upon which further automated analysis can be built. The nomenclature defined by the ontology will foster clearer communication between biologists, and also standardize terms used by data publishers in the results of analysis programs. The overriding aim of this ontology is the facilitation of consistent annotation of genomes through computational methods, rather than human annotators. To this end, the ontology includes definitions that support computer analysis and automated transfer of annotations between genomes, rather than relying upon human mediation.  相似文献   
16.
Here we report on the discovery of a series of maleimides which have high potency and good selectivity for GSK-3β. The incorporation of polar groups afforded compounds with good bioavailability. The most potent compound 34 has an IC50 of 0.6 nM for GSK-3β, over 100-fold selectivity against a panel of other kinases, and shows efficacy in rat osteoporosis models. The X-ray structure of GSK-3β protein with 34 bound revealed the binding mode of the template and provided insights for future optimization opportunities.  相似文献   
17.
18.

Background

Smoking and passive smoking are collectively the biggest preventable cause of death in Bangladesh, with major public health burden of morbidity, disability, mortality and community costs. The available studies of tobacco use in Bangladesh, however, do not necessarily employ nationally representative samples needed to monitor the problem at a national scale. This paper examines the prevalence and patterns of tobacco use among adults in Bangladesh and the changes over time using large nationally representative comparable surveys.

Methods

Using data from two enumerations of the International Tobacco Control (ITC) Bangladesh Project conducted in 2009 and 2012, prevalence estimates are obtained for all tobacco products by socio-economic determinants and sample types of over 90,000 individuals drawn from over 30,000 households. Household level sample weights are used to obtain nationally representative prevalence estimates and standard errors. Statistical tests of difference in the estimates between two time periods are based on a logistic regression model that accounts for the complex sampling design. Using a multinomial logit model, the time trend in tobacco use status is identified to capture the effects of macro level determinants including changes in tobacco control policies.

Results

Between 2009 and 2012, overall tobacco use went down from 42.4% to 36.3%. The decline is more pronounced with respect to smokeless tobacco use than smoking. The prevalence of exclusive cigarette smoking went up from 7.2% to 10.6%; exclusive bidi smoking remained stable at around 2%; while smoking both cigarette and bidi went down from 4.6% to 1.8%; exclusive smokeless tobacco use went down from 20.2% to 16.9%; and both smokeless tobacco use and smoking went down from 8.4% to 5.1%. In general, the prevalence of tobacco use is higher among men, increases from younger to older age groups, and is higher among poorer people. Smoking prevalence is the highest among the slum population, followed by the tribal population, the national population and the border area population, suggesting greater burden of tobacco use among the disadvantaged groups.

Conclusions

The overall decline in tobacco use can be viewed as a structural shift in the tobacco market in Bangladesh from low value products such as bidi and smokeless tobacco to high value cigarettes, which is expected with the growth in income and purchasing power of the general population. Despite the reduction in overall tobacco use, the male smoking prevalence in Bangladesh is still high at 37%. The world average of daily smoking among men is 31.1%. The Tobacco Control Act 2005 and the Amendment have yet to make a significant impact in curbing tobacco usage in Bangladesh. The findings in this paper further suggest that the tobacco control policies in Bangladesh need to include targeted interventions to restrain the use of particular types of tobacco products among specific demographic and socio-economic groups of the population, such as smoked tobacco among men, smokeless tobacco among women, and both smoked and smokeless tobacco among those living in rural areas, those in low socio-economic status and those belonging to the tribal and the slum population.  相似文献   
19.
Parker ET  Lollar P 《Biochemistry》2007,46(34):9737-9742
Blood coagulation factor VIII (fVIII) is activated by thrombin to form an A1/A2/A3-C1-C2 heterotrimer, which functions as a cofactor for factor IXa during intrinsic pathway factor X activation. Human thrombin-activated fVIII (fVIIIa) decays rapidly because of first-order dissociation of the A2 subunit, which may function to regulate the coagulation mechanism. The three fVIII A domains each consist of two cupredoxin-like subdomains. Substitution of the COOH-terminal A1 subdomain of porcine fVIIIa, which decays more slowly than human fVIIIa, reduces the dissociation rate constant for fVIIIa decay. Examination of a human fVIII A1-A2-A3 homology model [Pemberton, S., et al. (1997) Blood 89, 2413-2421) revealed a possible interaction between Q316 in the FG helix of the COOH-terminal A1 subdomain and M539 in the FG helix of the NH2-terminal A2 subdomain, which are sites where human and porcine fVIII differ. Decays of purified recombinant human and porcine fVIIIa and the human fVIIIa mutants Q316H, M539L and Q316H/M539L were compared at 23 and 37 degrees C. The decay rates of the Q316H and Q316H/M539L mutants, but not the M539L mutant, were significantly slower than human fVIIIa. These results indicate that the FG helix of the COOH-terminal A1 cupredoxin-like subdomain of fVIII may be under selective pressure by the requirements of hemostatic balance.  相似文献   
20.
New modifications on the C-8 4-aminobenzyl unit of the previously reported 3-alkyl-1,8-dibenzylxanthine inhibitors of cPEPCK are presented. The most active compound reported here is the 5-chloro-1,3-dimethyl-1H-pyrazole-4-sulfonic acid amide derivative 2 with an IC(50) of 0.29+/-0.08 microM. An X-ray analysis of a heteroaromatic sulfonamide is presented showing a new pi-pi interaction.  相似文献   
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