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41.
The stabilities of orange oil emulsions stabilized with various concentrations of two different types of corn fiber gum (CFG-1 and 2) isolated from coarse (pericarp) and fine (endosperm) fiber from corn wet milling have been studied. The emulsion stabilities in all these studies increased with increasing gum concentration up to a gum-to-oil ratio of 0.05, and after that it either levels off or changes very slightly. These results indicate that only 0.25% of CFG is required to make stable emulsion containing 5% orange oil under the experimental conditions used in this study. At this CFG concentration, CFG-2 from each fiber source was found to be a superior emulsifier relative to the corresponding CFG-1 from each source in a 10-day emulsion stability study at room temperature. The emulsion stability was also investigated by confocal laser scanning microscopy measurement, and it was found that CFG-1 and 2 from both coarse and fine fiber made stable emulsions with an average particle size of less than 1 mum for 10 days at room temperature. Sugar composition analysis of CFGs from both sources indicated that they were typical galactoglucuronoarabinoxylans containing mainly 55-59% xylose, 29-36% arabinose, and 4-6% galactose as neutral sugars and 3-5% glucuronic acid. Methylation analysis revealed a highly branched structure of all CFGs, in which only 16-25% of the 1--> 4-linked xylose residues were not substituted at O-2 and/or O-3. Arabinose is present both as a terminal residue and at branch points. 相似文献
42.
Ultrasensitive radars and uninstrumented jet aircraft in concert have probed regions of the clear atmosphere in search of clear-air turbulence. All sources of clear-air radar echoes above 6 kilometers that were probed simultaneously by the aircraft were found to be turbulent. 相似文献
43.
Large-scale copy number polymorphism in the human genome 总被引:1,自引:0,他引:1
Sebat J Lakshmi B Troge J Alexander J Young J Lundin P Månér S Massa H Walker M Chi M Navin N Lucito R Healy J Hicks J Ye K Reiner A Gilliam TC Trask B Patterson N Zetterberg A Wigler M 《Science (New York, N.Y.)》2004,305(5683):525-528
The extent to which large duplications and deletions contribute to human genetic variation and diversity is unknown. Here, we show that large-scale copy number polymorphisms (CNPs) (about 100 kilobases and greater) contribute substantially to genomic variation between normal humans. Representational oligonucleotide microarray analysis of 20 individuals revealed a total of 221 copy number differences representing 76 unique CNPs. On average, individuals differed by 11 CNPs, and the average length of a CNP interval was 465 kilobases. We observed copy number variation of 70 different genes within CNP intervals, including genes involved in neurological function, regulation of cell growth, regulation of metabolism, and several genes known to be associated with disease. 相似文献
44.
DN Basov SI Woods AS Katz EJ Singley RC Dynes M Xu DG Hinks CC Homes M Strongin 《Science (New York, N.Y.)》1999,283(5398):49-52
Analysis of the interlayer infrared conductivity of cuprate high-transition temperature superconductors reveals an anomalously large energy scale extending up to midinfrared frequencies that can be attributed to formation of the superconducting condensate. This unusual effect is observed in a va- riety of materials, including Tl2Ba2CuO6+x, La2-xSrxCuO4, and YBa2Cu3O6.6, which show an incoherent interlayer response in the normal state. Midinfrared range condensation was examined in the context of sum rules that can be formulated for the complex conductivity. One possible interpretation of these experiments is in terms of a kinetic energy change associated with the superconducting transition. 相似文献
45.
The degree of interaction of component waves making up a single electroencephalogram trace was strongly correlated with alpha activity, lead placement, and state of consciousness. Significant quadratic coupling of the waves was found only for awake subjects with high alpha activity. For these subjects about 50 percent of beta activity can be attributed to harmonic coupling with the alpha peak. During sleep, the degree of interaction was of borderline significance and did not follow a consistent pattern with respect to subject, frequency, state, or lead. 相似文献
46.
A 10-year-old, female Newfoundland-cross dog was presented for evaluation of chronic intermittent unilateral epistaxis, nasal stertor, and sneezing. Nasal magnetic resonance imaging revealed a 3 x 5-cm mass in the left nasal cavity. Histopathological evaluation of nasal biopsies determined that the mass was a malignant melanoma. The mass was surgically resected and treated with bilateral opposed photon-beam radiation. This is the first report to describe the presentation, diagnosis, and treatment of an intranasal malignant melanoma in a dog. 相似文献
47.
Reddy V Nathues A Le Corre L Sierks H Li JY Gaskell R McCoy T Beck AW Schröder SE Pieters CM Becker KJ Buratti BJ Denevi B Blewett DT Christensen U Gaffey MJ Gutierrez-Marques P Hicks M Keller HU Maue T Mottola S McFadden LA McSween HY Mittlefehldt D O'Brien DP Raymond C Russell C 《Science (New York, N.Y.)》2012,336(6082):700-704
Multispectral images (0.44 to 0.98 μm) of asteroid (4) Vesta obtained by the Dawn Framing Cameras reveal global color variations that uncover and help understand the north-south hemispherical dichotomy. The signature of deep lithologies excavated during the formation of the Rheasilvia basin on the south pole has been preserved on the surface. Color variations (band depth, spectral slope, and eucrite-diogenite abundance) clearly correlate with distinct compositional units. Vesta displays the greatest variation of geometric albedo (0.10 to 0.67) of any asteroid yet observed. Four distinct color units are recognized that chronicle processes--including impact excavation, mass wasting, and space weathering--that shaped the asteroid's surface. Vesta's color and photometric diversity are indicative of its status as a preserved, differentiated protoplanet. 相似文献
48.
Simultaneously mitigating near-term climate change and improving human health and food security 总被引:3,自引:0,他引:3
Shindell D Kuylenstierna JC Vignati E van Dingenen R Amann M Klimont Z Anenberg SC Muller N Janssens-Maenhout G Raes F Schwartz J Faluvegi G Pozzoli L Kupiainen K Höglund-Isaksson L Emberson L Streets D Ramanathan V Hicks K Oanh NT Milly G Williams M Demkine V Fowler D 《Science (New York, N.Y.)》2012,335(6065):183-189
Tropospheric ozone and black carbon (BC) contribute to both degraded air quality and global warming. We considered ~400 emission control measures to reduce these pollutants by using current technology and experience. We identified 14 measures targeting methane and BC emissions that reduce projected global mean warming ~0.5°C by 2050. This strategy avoids 0.7 to 4.7 million annual premature deaths from outdoor air pollution and increases annual crop yields by 30 to 135 million metric tons due to ozone reductions in 2030 and beyond. Benefits of methane emissions reductions are valued at $700 to $5000 per metric ton, which is well above typical marginal abatement costs (less than $250). The selected controls target different sources and influence climate on shorter time scales than those of carbon dioxide-reduction measures. Implementing both substantially reduces the risks of crossing the 2°C threshold. 相似文献
49.
Two different extraction methods for extracting sorghum (Sorghum bicolor L. Moench.) storage proteins for free zone capillary electrophoresis (FZCE) analysis were compared. A traditional solvent based on 60% t‐butanol was compared with a pH 10 borate buffer containing the anionic detergent SDS followed by precipitation of nonkafirins using 60% t‐butanol. FZCE analysis of both types of extracts showed identical patterns, despite the fact that the SDS should have given all proteins equal charge‐to‐mass ratios. This methodology was also successfully applied to maize proteins. The use of t‐butanol to precipitate nonkafirins, combined with electrophoresis at low pH, is thought to have removed the SDS from the storage proteins. The SDS extraction procedure produced more stable extracts for FZCE analysis. These extracts could also be used directly for SDS capillary electrophoresis (SDS‐CE) separations. Kafirins from 15 genotypes were extracted with this procedure and analyzed by FZCE and SDS‐CE. Resolution of the kafirins by FZCE was much higher than the SDS‐CE, demonstrating that the kafirin proteins possessed a high level of charge density variability within a relatively small molecular size distribution. Two distinct groups of α‐kafirins could be seen in the FZCE electropherograms. 相似文献
50.
The landscape scale distributions of adult male click beetles of the species Agriotes lineatus, A. obscurus and A. sputator, and the cranefly Tipula paludosa were studied using traps along transects over 2 years. The transects (0.7–1.7 km with either sex pheromone (Agriotes) or water (T. paludosa) traps at 100 m spacings) were in an area of mixed organic land use. Agriotes lineatus was the most numerous click beetle caught even though its larvae were absent from these fields. Greater trap counts were found for all taxa except A. obscurus in grassland. The number of click beetles were influenced by the sampling year, crop type and the species, and interactions of other variables, suggesting that sex pheromone trap counts exhibit variability because of the complexity of the environment. Trap catches were spatially clustered with the exception of A. lineatus in 2005 which had a random distribution. Only A. sputator showed a significant, positive relationship between counts in 2005 and 2006. Variation in catch count of crane flies was largely determined by crop type. We conclude that Agriotes spp. disperse widely and may be recruited from outside the field which makes the interpretation of sex pheromone trap counts scientifically challenging. 相似文献