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31.
32.
Background
In this paper we present a novel scene retargeting technique to reduce the visual scene while maintaining the size of the key features. The algorithm is scalable to implementation onto portable devices, and thus, has potential for augmented reality systems to provide visual support for those with tunnel vision. We therefore test the efficacy of our algorithm on shrinking the visual scene into the remaining field of view for those patients. 相似文献33.
34.
Cereal-legume intercropping plays a vital role in the subsistence food production system that prevails in the arid regions. It not only provides profitable crop productivity for agricultural communities but also plays an important role in improving soil fertility. Therefore, the present research was conducted to assess the effect of the organic and mineral fertilizers on the forage yield and nutritional value in barley-pea intercropping system. The results revealed that the quality of forage grass is significantly influenced by both organic and inorganic fertilizer. Thus, organic fertilizer application has significantly influenced the dry matter (DM), crude ash (CA), crude protein (CP), neutral detergent fiber (NDF), and acid detergent fiber (ADF). Among the treatments, organic fertilizer added at rate of 35 m−3 ha−1 produced the maximum fresh and dry matter in barley and peas. In addition, the same level of organic fertilizer also improved silage composition by significantly increasing the protein and fiber content and showed highest the values. Based on overall results, it is concluded that organic fertilizer treatment (35 m−3 ha−1) has the potential as an effective strategy to improve the productivity and nutritional quality of the barley-pea intercropping system in arid areas. The results revealed that organic fertilizer can be utilized in sustainable agricultural as a source of nutrients for numerous various crops under arid conditions. 相似文献
35.
Walid Nosir Jim McDonald Steve Woodward 《Journal of industrial microbiology & biotechnology》2011,38(1):21-27
Fusaric acid (FA) (5-n-butylpuridine 2-carboxyl acid), a highly toxic secondary metabolite produced by Fusarium oxysporum strains, plays a significant role in disease development. The abilities of three F. oxysporum f. sp. gladioli (Massey) Snyder and Hansen isolates (G010; 649-91; and 160-57) to produce FA in infected Gladiolus corm tissues was evaluated in vitro in relation to the presence of two biological control agents, Trichoderma harzianum T22, and Aneurinobacillus migulanus. Pathogenicity tests were used to differentiate between the abilities of the F. oxysporum strains to secrete FA. FA was identified using LC/MS and quantified using HPLC. Isolate G010 was significantly more virulent
(P < 0.01) on Gladiolus grandiflorus corms; it secretes 1.8 μM FA/g fresh weight corm into inoculated Gladiolus. Moreover, G010 was the only isolate that produced FA among the three examined isolates. There was a correlation between
the corm lesion area and the FA secretion ability of F. oxysporum f. sp. gladioli (P < 0.001; r
2 = 0.96). No FA was detected in PDA cultures of F.oxysporum f. sp. gladioli isolates. The presence of T. harzianum T22 appeared to prevent FA secretion into the corms. In the presence of A. migulanus, however, the amount of FA secreted into the corm tissues increased. These results support the use of T. harzianum as an effective biological control agent against F. oxysporum f. sp. gladioli. 相似文献
36.
Plant Zn/Cd/Pb/Co P1B-ATPases (HMAs) play different roles, among which are the control of metal transport from the roots to the shoot and/or from the cytoplasm into the cell vacuole. Transferring the knowledge acquired on HMAs from model species to HMAs from other species requires one to identify orthologues in these other species. Through an extensive screening of the public sequence databases, 96 plant P1B-ATPases showing orthology to any of the AtHMA1, AtHMA2, AtHMA3 or AtHMA4 isoforms were identified from 32 plant species belonging to 15 botanical families. The number of paralogues within a species varied greatly from species to species, even within a specific botanical family, suggesting that gene duplication events occurred after speciation. The phylogenetic tree gathering the Zn/Cd/Pb/Co P1B-ATPases was strongly structured according to the botanical family to which the sequences could be related to. In particular, no strict orthology relationship links the Brassicaceae HMAs to the non-Brassicaceae or the Poaceae ones. Recent data showed that the sole rice HMA characterised to date displays different functional properties from the Arabidopsis HMAs. Altogether, data suggest that it might be risky to directly transfer the knowledge acquired through the study of HMAs in model plant species to HMAs from other species. 相似文献
37.
Farrar CT Kamoun WS Ley CD Kim YR Catana C Kwon SJ Rosen BR Jain RK Sorensen AG 《PloS one》2011,6(3):e17228
MRI biomarkers of tumor edema, vascular permeability, blood volume, and average vessel caliber are increasingly being employed to assess the efficacy of tumor therapies. However, the dependence of these biomarkers on a number of physiological factors can compromise their sensitivity and complicate the assessment of therapeutic efficacy. Here we examine the response of these MRI tumor biomarkers to cediranib, a potent vascular endothelial growth factor receptor (VEGFR) inhibitor, in an orthotopic mouse glioma model. A significant increase in the tumor volume and relative vessel caliber index (rVCI) and a slight decrease in the water apparent diffusion coefficient (ADC) were observed for both control and cediranib treated animals. This contrasts with a clinical study that observed a significant decrease in tumor rVCI, ADC and volume with cediranib therapy. While the lack of a difference between control and cediranib treated animals in these biomarker responses might suggest that cediranib has no therapeutic benefit, cediranib treated mice had a significantly increased survival. The increased survival benefit of cediranib treated animals is consistent with the significant decrease observed for cediranib treated animals in the relative cerebral blood volume (rCBV), relative microvascular blood volume (rMBV), transverse relaxation time (T2), blood vessel permeability (K(trans)), and extravascular-extracellular space (ν(e)). The differential response of pre-clinical and clinical tumors to cediranib therapy, along with the lack of a positive response for some biomarkers, indicates the importance of evaluating the whole spectrum of different tumor biomarkers to properly assess the therapeutic response and identify and interpret the therapy-induced changes in the tumor physiology. 相似文献
38.
Mohan Babu Roland Arnold Cedoljub Bundalovic-Torma Alla Gagarinova Keith S. Wong Ashwani Kumar Geordie Stewart Bahram Samanfar Hiroyuki Aoki Omar Wagih James Vlasblom Sadhna Phanse Krunal Lad Angela Yeou Hsiung Yu Christopher Graham Ke Jin Eric Brown Ashkan Golshani Philip Kim Gabriel Moreno-Hagelsieb Jack Greenblatt Walid A. Houry John Parkinson Andrew Emili 《PLoS genetics》2014,10(2)
Large-scale proteomic analyses in Escherichia coli have documented the composition and physical relationships of multiprotein complexes, but not their functional organization into biological pathways and processes. Conversely, genetic interaction (GI) screens can provide insights into the biological role(s) of individual gene and higher order associations. Combining the information from both approaches should elucidate how complexes and pathways intersect functionally at a systems level. However, such integrative analysis has been hindered due to the lack of relevant GI data. Here we present a systematic, unbiased, and quantitative synthetic genetic array screen in E. coli describing the genetic dependencies and functional cross-talk among over 600,000 digenic mutant combinations. Combining this epistasis information with putative functional modules derived from previous proteomic data and genomic context-based methods revealed unexpected associations, including new components required for the biogenesis of iron-sulphur and ribosome integrity, and the interplay between molecular chaperones and proteases. We find that functionally-linked genes co-conserved among γ-proteobacteria are far more likely to have correlated GI profiles than genes with divergent patterns of evolution. Overall, examining bacterial GIs in the context of protein complexes provides avenues for a deeper mechanistic understanding of core microbial systems. 相似文献
39.
Expression of the gene encoding ribosome modulation factor (RMF), as measured using an rmf-lacZ gene fusion, increased with decreasing pH in exponential phase cultures of Escherichia coli. Expression was inversely proportional to the growth rate and independent of the acidifying agent used and it was concluded
that expression of rmf was growth rate controlled in exponential phase under acid conditions. Increased rmf expression during exponential phase was not accompanied by the formation of ribosome dimers as occurs during stationary phase.
Nor did it appear to have a significant effect on cell survival under acid stress since the vulnerability of an RMF-deficient
mutant strain was similar to that of the parent strain. Ribosome degradation was increased in the mutant strain compared to
the parent strain at pH 3.75. Also, the peptide elongation rate was reduced in the mutant strain but not the parent during
growth under acid conditions. It is speculated that the function of RMF during stress-induced reduction in growth rate is
two-fold: firstly to prevent reduced elongation efficiency by inactivating surplus ribosomes and thus limiting competition
for available protein synthesis factors, and secondly to protect inactivated ribosomes from degradation. 相似文献
40.
Gribun A Kimber MS Ching R Sprangers R Fiebig KM Houry WA 《The Journal of biological chemistry》2005,280(16):16185-16196
ClpP is a conserved serine-protease with two heptameric rings that enclose a large chamber containing the protease active sites. Each ClpP subunit can be divided into a handle region, which mediates ring-ring interactions, and a head domain. ClpP associates with the hexameric ATPases ClpX and ClpA, which can unfold and translocate substrate proteins through the ClpP axial pores into the protease lumen for degradation. We have determined the x-ray structure of Streptococcus pneumoniae ClpP(A153P) at 2.5 A resolution. The structure revealed two novel features of ClpP which are essential for ClpXP and ClpAP functional activities. First, the Ala --> Pro mutation disrupts the handle region, resulting in an altered ring-ring dimerization interface, which, in conjunction with biochemical data, demonstrates the unusual plasticity of this region. Second, the structure shows the existence of a flexible N-terminal loop in each ClpP subunit. The loops line the axial pores in the ClpP tetradecamer and then protrude from the protease apical surface. The sequence of the N-terminal loop is highly conserved in ClpP across all kingdoms of life. These loops are essential determinants for complex formation between ClpP and ClpX/ClpA. Mutation of several amino acid residues in this loop or the truncation of the loop impairs ClpXP and ClpAP complex formation and prevents the coupling between ClpX/ClpA and ClpP activities. 相似文献