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681.
682.
Life-cycle analyses, energy analyses, and a range of utilization efficiencies were developed to determine the carbon dioxide (CO2) and fossil fuel (FF) saved by various solid wood products, wood energy, and unharvested forests. Some products proved very efficient in CO2 and FF savings, while others did not. Not considering forest regrowth after harvest or burning if not harvested, efficient products save much more CO2 than the standing forest; but wood used only for energy generally saves slightly less. Avoided emissions (using wood in place of steel and concrete) contributes the most to CO2 and FF savings compared to the product and wood energy contributions. Burning parts of the harvested logs that are not used for products creates an additional CO2 and FF savings. Using wood substitutes could save 14 to 31% of global CO2 emissions and 12 to 19% of global FF consumption by using 34 to 100% of the world’s sustainable wood growth. Maximizing forest CO2 sequestration may not be compatible with biodiversity. More CO2 can be sequestered synergistically in the products or wood energy and landscape together than in the unharvested landscape. Harvesting sustainably at an optimum stand age will sequester more carbon in the combined products, wood energy, and forest than harvesting sustainably at other ages.  相似文献   
683.

Background

It is generally accepted that controlled vocabularies are necessary to systematically integrate data from various sources. During the last decade, several plant ontologies have been developed, some of which are community specific or were developed for a particular purpose. In most cases, the practical application of these ontologies has been limited to systematically storing experimental data. Due to technical constraints, complex data structures and term redundancies, it has been difficult to apply them directly into analysis tools.

Results

Here, we describe a simplified and cross-species compatible set of controlled vocabularies for plant anatomy, focussing mainly on monocotypledonous and dicotyledonous crop and model plants. Their content was designed primarily for their direct use in graphical visualization tools. Specifically, we created annotation vocabularies that can be understood by non-specialists, are minimally redundant, simply structured, have low tree depth, and we tested them practically in the frame of Genevestigator.

Conclusions

The application of the proposed ontologies enabled the aggregation of data from hundreds of experiments to visualize gene expression across tissue types. It also facilitated the comparison of expression across species. The described controlled vocabularies are maintained by a dedicated curation team and are available upon request.
  相似文献   
684.
Ozonolysis is a major tropospheric removal mechanism for unsaturated hydrocarbons and proceeds via "Criegee intermediates"--carbonyl oxides--that play a key role in tropospheric oxidation models. However, until recently no gas-phase Criegee intermediate had been observed, and indirect determinations of their reaction kinetics gave derived rate coefficients spanning orders of magnitude. Here, we report direct photoionization mass spectrometric detection of formaldehyde oxide (CH(2)OO) as a product of the reaction of CH(2)I with O(2). This reaction enabled direct laboratory determinations of CH(2)OO kinetics. Upper limits were extracted for reaction rate coefficients with NO and H(2)O. The CH(2)OO reactions with SO(2) and NO(2) proved unexpectedly rapid and imply a substantially greater role of carbonyl oxides in models of tropospheric sulfate and nitrate chemistry than previously assumed.  相似文献   
685.
This study investigates the sensitivity of local synchrony to movement patterns of the Ringlet butterfly (Aphantopus hyperantus). We examine whether population synchrony, describing the correlated fluctuations of conspecific populations, may prove an effective surrogate measure for monitoring functional connectivity in this species without the requirement of exhaustive sampling. We compared the effect on population synchrony of two different distance measures, direct (Euclidean) distance and distance via woodland rides and edges, and also of habitat matrix composition. Population synchrony of A. hyperantus was calculated as the pairwise correlation between population time-series using 20?years of data from UK butterfly monitoring scheme transects. Local population synchrony was better explained by distance via woodland edges than direct distance, especially for woodland-dominated transects. These results are consistent with mark-recapture data previously collected on the Ringlet butterfly. The results indicate a sensitivity of population synchrony to butterfly local dispersal behaviour, particularly, to the use of habitat corridors and other functional dispersal routes. Population synchrony is considered to have potential as a surrogate measure of functional connectivity. With development, this method could become a valuable conservation tool for identifying important landscape features which promote species?? connectivity.  相似文献   
686.
One-hundred and seventy-five labradoodles underwent slit-lamp biomicroscopy and direct and indirect ophthalmoscopy between January 2008 and December 2009. These examinations were performed at shows by the first author. In addition, labradoodle eye certificates from the 2008 and 2009 British Veterinary Association/Kennel Club/International Sheep Dog Society (BVA/KC/ISDS) Eye Scheme were analysed (n=260). The results of the examinations were reviewed, and all ophthalmic abnormalities were recorded. The prevalence of any abnormality was compared with that reported by the Eye Scheme and the KC during 2009 for the labrador retriever, miniature, toy and standard poodles. Multifocal retinal dysplasia (MRD) was identified in 20 labradoodles (4.6 per cent), and cataracts were identified in 16 labradoodles (3.7 per cent). The prevalence of MRD in labradoodles was significantly greater than in labrador retrievers (P<0.0001). There was no difference in the prevalence of cataract between labradoodles and labrador retrievers (P=0.4866). The results of this study suggest that MRD is a relatively common finding in the labradoodle population in the UK. Given such an apparent high prevalence of MRD, routine screening for hereditary eye disease before breeding is advised for this increasingly popular new crossbreed.  相似文献   
687.
Inflammatory bowel disease (IBD) is a common cause of chronic diarrhoea in dogs. In people, specific cytokine patterns attributed to T cell subsets, especially T helper cell [Th]1, Th17 and regulatory T(reg) cells have emerged in IBD. In contrast, no specific involvement of a distinct T cell subset has been described so far in canine IBD. Thus, the aim of the present study was to assess gene expression of signature cytokines in duodenal tissues from 18 German shepherd dogs with IBD (group 1), 33 dogs of other breeds with IBD (group 2) and 15 control dogs (group 3). Relative quantification of IL-17A, IL-22, IL-10, IFNy and TGFβ was performed. Expression of IL-17A was significantly lower in groups 1 and 2 compared to group 3 (p=0.014), but no difference in the expression of IL-22 (p=0.839), IFNγ (p=0.359), IL-10 (p=0.085) or TGFβ (p=0.551) across groups was detected. Thus, no clear evidence for the involvement of Th-17 signature cytokines in canine IBD at the mRNA level could be shown. The contribution of specific T cell subsets to the pathogenesis of canine IBD warrants further investigation.  相似文献   
688.
Eating inappropriately prepared poultry meat is a major cause of foodborne salmonellosis. Our objectives were to determine the efficacy of feed and water additives (other than competitive exclusion and antimicrobials) on reducing Salmonella prevalence or concentration in broiler chickens using systematic review-meta-analysis and to explore sources of heterogeneity found in the meta-analysis through meta-regression. Six electronic databases were searched (Current Contents (1999-2009), Agricola (1924-2009), MEDLINE (1860-2009), Scopus (1960-2009), Centre for Agricultural Bioscience (CAB) (1913-2009), and CAB Global Health (1971-2009)), five topic experts were contacted, and the bibliographies of review articles and a topic-relevant textbook were manually searched to identify all relevant research. Study inclusion criteria comprised: English-language primary research investigating the effects of feed and water additives on the Salmonella prevalence or concentration in broiler chickens. Data extraction and study methodological assessment were conducted by two reviewers independently using pretested forms. Seventy challenge studies (n=910 unique treatment-control comparisons), seven controlled studies (n=154), and one quasi-experiment (n=1) met the inclusion criteria. Compared to an assumed control group prevalence of 44 of 1000 broilers, random-effects meta-analysis indicated that the Salmonella cecal colonization in groups with prebiotics (fructooligosaccharide, lactose, whey, dried milk, lactulose, lactosucrose, sucrose, maltose, mannanoligosaccharide) added to feed or water was 15 out of 1000 broilers; with lactose added to feed or water it was 10 out of 1000 broilers; with experimental chlorate product (ECP) added to feed or water it was 21 out of 1000. For ECP the concentration of Salmonella in the ceca was decreased by 0.61log(10)cfu/g in the treated group compared to the control group. Significant heterogeneity (Cochran's Q-statistic p≤0.10) was observed among studies examining all organic acids (controlled or challenge experiments), butyric acid, formic acid, a formic/propionic acid mixture, fermented liquid feed, and D-mannose. Meta-regressions were conducted to examine the source of heterogeneity among studies. For prevalence outcomes, 36% and 60% of the total variance was within and between studies, respectively. For concentration outcomes, 39% and 33% of the total variance was within and between studies, respectively. Inadequate blinding and randomization was common, and no studies undergoing meta-analysis or meta-regression were conducted on a commercial farm. The strength of evidence of the effect of these additives was very low. Studies conducted under commercial conditions are needed to understand the potential benefit of these interventions for the poultry industry and to improve the strength of evidence of the effectiveness of these additives.  相似文献   
689.
Monitoring of the pathogen spectrum in grain peas (Pisum sativum L.) was conducted in Germany between 2005 and 2007. The outcome of this study implies that the infections of pathogens depend on the annual weather condition and the geographic area.Ascochyta pinodes, which infects aerial plant organs, was the pathogen found most frequently (on average 61, 8%). Especially in years with moist weather conditions a more severe spreading of the pathogen could be observed. Similarly, the occurrence ofBotrytis cinerea depends on the weather conditions. In 2007 were optimal conditions for infections and consequentlyB. cinerea was found with a high frequency of about 70%. Regarding diseases on root and stem base, this study clearly shows that infection of less prominent Fusarium species, such asF. redolens andF. avenaceum was significantly higher compared toF. oxysporum andF. solani.  相似文献   
690.
A 2-year study of host association, molecular characterisation and vector transmission of a phytoplasma related to the 16SrII group in a vineyard of south-eastern Serbia was conducted. Grapevine, eight common weeds and 31 Auchenorrhyncha species were collected and analysed for phytoplasma presence. PCR-RFLP analyses of the 16S rRNA gene identified the presence of a new strain of phytoplasma related to the 16SrII group in P. hieracioides with symptoms of stunting or bushy stunting. Grapevine samples, all without symptoms, were negative for phytoplasma presence. Plants of Erigeron annuus, Cynodon dactylon, Daucus carota and P. hieracioides, either exhibiting symptoms of yellowing or without symptoms, were positive for the presence of stolbur phytoplasma. Among the tested cicada species, seven were infected with phytoplasmas from the aster yellows group, two with stolbur phytoplasma, two with 16SrII phytoplasma, and one with the 16SrV-C phytoplasma subgroup. The phytoplasma strain of the 16SrII group was recorded in approximately 50?% of the collected leafhopper species Neoaliturus fenestratus and in a few specimens of the planthopper Dictyophara europaea. The vector status of N. fenestratus was tested using the second generation of the planthopper in two separate transmission trials with P. hieracioides and periwinkle seedlings. In both tests, the leafhopper successfully transmitted 16SrII phytoplasma to exposed plants, proving its role as a natural vector of this phytoplasma in Europe. A finer molecular characterisation and phylogenetic relatedness of the 16SrII phytoplasma strain by sequence analyses of the 16S rRNA and ribosomal protein genes rpl22-rps3 indicated that it was most closely related to the 16SrII-E subgroup.  相似文献   
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