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91.
Signatures of adaptation to obligate biotrophy in the Hyaloperonospora arabidopsidis genome 总被引:2,自引:0,他引:2
Baxter L Tripathy S Ishaque N Boot N Cabral A Kemen E Thines M Ah-Fong A Anderson R Badejoko W Bittner-Eddy P Boore JL Chibucos MC Coates M Dehal P Delehaunty K Dong S Downton P Dumas B Fabro G Fronick C Fuerstenberg SI Fulton L Gaulin E Govers F Hughes L Humphray S Jiang RH Judelson H Kamoun S Kyung K Meijer H Minx P Morris P Nelson J Phuntumart V Qutob D Rehmany A Rougon-Cardoso A Ryden P Torto-Alalibo T Studholme D Wang Y Win J Wood J Clifton SW Rogers J Van den Ackerveken G Jones JD 《Science (New York, N.Y.)》2010,330(6010):1549-1551
Many oomycete and fungal plant pathogens are obligate biotrophs, which extract nutrients only from living plant tissue and cannot grow apart from their hosts. Although these pathogens cause substantial crop losses, little is known about the molecular basis or evolution of obligate biotrophy. Here, we report the genome sequence of the oomycete Hyaloperonospora arabidopsidis (Hpa), an obligate biotroph and natural pathogen of Arabidopsis thaliana. In comparison with genomes of related, hemibiotrophic Phytophthora species, the Hpa genome exhibits dramatic reductions in genes encoding (i) RXLR effectors and other secreted pathogenicity proteins, (ii) enzymes for assimilation of inorganic nitrogen and sulfur, and (iii) proteins associated with zoospore formation and motility. These attributes comprise a genomic signature of evolution toward obligate biotrophy. 相似文献
92.
Widespread divergence between incipient Anopheles gambiae species revealed by whole genome sequences
Lawniczak MK Emrich SJ Holloway AK Regier AP Olson M White B Redmond S Fulton L Appelbaum E Godfrey J Farmer C Chinwalla A Yang SP Minx P Nelson J Kyung K Walenz BP Garcia-Hernandez E Aguiar M Viswanathan LD Rogers YH Strausberg RL Saski CA Lawson D Collins FH Kafatos FC Christophides GK Clifton SW Kirkness EF Besansky NJ 《Science (New York, N.Y.)》2010,330(6003):512-514
The Afrotropical mosquito Anopheles gambiae sensu stricto, a major vector of malaria, is currently undergoing speciation into the M and S molecular forms. These forms have diverged in larval ecology and reproductive behavior through unknown genetic mechanisms, despite considerable levels of hybridization. Previous genome-wide scans using gene-based microarrays uncovered divergence between M and S that was largely confined to gene-poor pericentromeric regions, prompting a speciation-with-ongoing-gene-flow model that implicated only about 3% of the genome near centromeres in the speciation process. Here, based on the complete M and S genome sequences, we report widespread and heterogeneous genomic divergence inconsistent with appreciable levels of interform gene flow, suggesting a more advanced speciation process and greater challenges to identify genes critical to initiating that process. 相似文献
93.
Seungkeun Lee So-Jeong Nam Changbaig Hyun 《Veterinary journal (London, England : 1997)》2010,183(2):196-200
Transcutaneous cardiac pacing (TCP) can be used in dogs with a high risk for bradyarrhythmias prior to anesthesia, either in an emergency room or intensive care unit setting. Furthermore, TCP can also be used on patients diagnosed with bradyarrhythmias that require temporary pacing at the induction of anesthesia for the implantation of a permanent pacemaker. Despite the importance of TCP in emergency medicine, no studies have evaluated the optimal size and placement of the transdermal electrodes crucial for the efficacy of TCP in dogs.This study evaluated four different sizes of electrodes (10.5, 20, 30 and 40 cm2), and four different anatomical sites (anterior–posterior, left–right, apex–base, modified left–right) in order to optimize the efficacy of TCP in dogs. Electrodes with a surface area of 20 cm2 and a modified left–right placement minimized the pacing current and involuntary skeletal muscular contraction (muscular twitching) and so achieved the most optimal effect of TCP in dogs. 相似文献
94.
Effect of hydrogen peroxide exposures on mucous cells and lysozymes of gill tissues of olive flounder Paralichthys olivaeceus
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We investigated the effects of hydrogen peroxide on mucous cells and lysozymes in gill tissue of olive flounder. Morphological analysis revealed significant changes in the number of mucous cells after exposure to 300 and 500 mg L ? 1 hydrogen peroxide; however, there was no detectable difference in the 100 mg L ? 1 group. Lysozyme activities declined gradually in the gill mucus, but in contrast activities in serum increased significantly following the completion of treatment. The hepatic c‐ and g‐type lysozyme levels showed significant responses, indicating that the liver is a major lysozyme producer in response to stress condition; however, in the head kidney, there were no significant changes in the g‐type lysozyme level in all the groups, while the only detectable difference with the c‐type gene in the 300 mg L ? 1. While the treatments showed no significant changes compared with the control for either branchial lysozyme, there were significant differences in c‐type lysozyme between the 3rd treatment and 5 day. Taken together, our data indicate that hydrogen peroxide treatment may lead to modulation of the innate immune response of olive flounder; therefore, the application of hydrogen peroxide in a field system will require more attention to dose and timing effects. 相似文献
95.
MH Chen SH Choi N Kozukue HJ Kim M Friedman 《Journal of agricultural and food chemistry》2012,60(36):9151-9161
We determined the phenolic, anthocyanin, and proanthocyanidin content of three brown, purple, and red rice brans isolated from different rice varieties using HPLC-PDA with the aid of 27 standards of known structure and matching unknown peaks to a spectral library of known compounds. Antioxidative capacities were determined by DPPH and ORAC and cell-inhibiting effects using an MTT assay. Based on the calculated IC(50) values, the light-brown bran had no effect, the purple bran exhibited a minor effect on leukemia and cervical cancer cells, and the red bran exhibited strong inhibitory effects on leukemia, cervical, and stomach cancer cells. High concentrations of protocatechuic acid and anthocyanins in purple bran and proanthocyanidins in red bran were identified. The red bran was further fractionated on a Sephadex column. Fraction 3 rich in proanthocyanidin oligomers and polymers had the greatest activity. Red bran has the potential to serve as a functional food supplement for human consumption. 相似文献
96.
The sponge cake baking test is accepted and routinely used as a standard quality evaluation tool of soft white wheat for Asian markets, but its lengthy and laborious procedure makes it unsuitable for the routine evaluation of a large number of wheat breeding lines. We simplified the sponge cake baking procedure in the egg‐whipping step and improved its consistency by replacement of the hand mixing of cake batter with mechanical mixing, using a wire whisk or a BeaterBlade paddle. Egg whipping and mechanical batter mixing conditions were optimized by comparing foam density, sponge cake volume, and crumb grain to those obtained by the conventional procedure. Foam density, sponge cake volume, and crumb grain comparable to the conventional 100 g flour procedure were obtained with modifications, including extension of whipping time without heat input using a 5 L KitchenAid mixer, one‐time water addition at 3 min before the completion of egg whipping instead of twice, as in the conventional procedure, and cake batter mixing with a KitchenAid wire whisk or a BeaterBlade paddle. For baking a 50 g flour cake, egg foam of appropriate density was obtained with increased whipping speed and shortened egg‐whipping time (8 min). The modified sponge cake baking procedure yielded egg‐foam density, cake volume, and crumb grain similar to the conventional procedure and effectively differentiated soft wheat flours of different quality. Sponge cake volume of 14 soft white wheat flours ranged from 1,134 to 1,426 mL with the conventional procedure, from 1,113 to 1,333 mL with the modified procedure of batter mixing with a wire whisk, from 1,108 to 1,360 mL with the modified procedure of batter mixing with a BeaterBlade paddle, and from 577 to 719 mL with the modified method of 50 g of flour and batter mixing with a wire whisk. The modified methods with the BeaterBlade paddle and wire whisk exhibited significant correlation in cake volume with a conventional procedure (r = 0.931, P < 0.001 and r = 0.925, P < 0.001, respectively). 相似文献
97.
Kyung?Min?Yoo Seok?Won?Lee Jae?Ryoun?YounEmail author Do?Heum?Yoon Young?Eun?Cho Jae-Pil?Yu Hyung?Sang?Park 《Fibers and Polymers》2003,4(2):89-96
A vertebral cage is a hollow medical device which is used in spine surgery. By implanting the cage into the spine column,
it is possible to restore disc and relieve pressure on the nerve roots. Most cages have been made of titanium alloys but they
detract the biocompatibility. Currently PEEK (polyether ether ketone) is applied to various implants because it has good properties
like heat resistance, chemical resistance, strength, and especially biocompatibility. A new shape of vertebral cage is designed
and injection molding of PEEK is considered for production. Before injection molding of the cage, it is needed to evaluate
process conditions and properties of the final product. Variables affecting the shrinkage of the cage are considered, e.g.,
injection time, packing pressure, mold temperature, and melt temperature. By using the numerical simulation program, MOLDFLOW,
several cases are studied. Data files obtained by MOLDFLOW analysis are used for stress analysis with ABAQUS, and shrinkage
and residual stress fields are predicted. With these results, optimum process conditions are determined. 相似文献
98.
Electrospun web may possibly be widely applied to protective garments or specialty textiles due to its high level of protection
as well as comfort. Of particular interest in this study is to develop waterproof-breathable fabric by applying electrospun
web of polyurethane directly onto the substrate fabric. The optimal electrospinning condition was examined with regards to
the concentration, applied voltage and tip-to-collector distance. Solvent-electospinning of polyurethane was performed at
the optimum condition, using N,N-dimethylacetamide as solvent. The thickness of 0.02 mm of electrospun web was applied onto
the polyester/nylon blended fabric. For comparison, the polyester/nylon fabrics were coated with 0.02 mm thickness of polyurethane
resin membranes adopting four different conditions. The electrospun PU web/fabric was compared to resin coated fabrics in
terms of water-proof and breathable properties. The electrospun web applied fabric showed higher air permeability, vapor transmission,
and thermal insulation properties than resin coated fabrics, which can be translated as greater comfort sensation of electrospun
applied fabrics. However, water resistance value of electrospun web applied fabric did not reach that of resin coated fabrics. 相似文献
99.
Sung Ok Sohn So Min Lee Yun Mi Kim Jeong Hyun Yeum Jin Hyun Choi Han Do Ghim 《Fibers and Polymers》2007,8(2):163-167
A durable aroma finishing for PET fabric was carried out by adopting poly(vinyl acetate) (PVAc) nanoparticles containing lavender
oil (LO) in core. Relatively small size of PVAc nanoparticles (ca. 244 nm of mean particle diameter) was expected to resist
the frictional destruction of the particles, which is frequently observed in cases of microcapsules. PVAc nanoparticles containing
LO in core were prepared by emulsification-diffusion method and their application as an aroma releasing agent for PET fabrics
was assessed through the observation of releasing profiles of LO in ethanol for experimental acceleration. Melamine-formaldehyde
(MF) microcapsules containing LO were also prepared and treated on fabrics for comparison. PVAc nanoparticles treated on PET
fabric showed higher initial releasing amount, which was ascribed to the enhanced surface area. After 2 days of releasing,
PET fabric treated with PVAc nanoparticles showed slower and more stable releasing profile and reached about 12 ppm of cumulative
release after 16 days, which was under two thirds of that with MF microcapsules. PVAc nanoparticles can be used as an agent
for durable aroma finishing of PET fabrics. 相似文献
100.
Ionic conductivity and mechanical properties of a mixed polymer matrix consisting of poly(ethylene glycol) (PEG) and cyanoresin
type M (CRM) with various lithium salts and plasticizer were examined. The CRM used was a copolymer of cyanoethyl pullulan
and cyanoethyl poly(vinyl alcohol) with a molar ratio of 1:1, mixed plasticizer was ethylene carbonate (EC) and propylene
carbonate (PC) at a volume ratio of 1:1. The conductive behavior of polymer electrolytes in the temperature range of 298∼338
K was investigated. The PEG/LiClO4 complexes exhibited the highest ionic conductivity of ∼10−5 S/cm at 25°C with the salt concentration of 1.5 M. In addition, the plasticized PEG/LiClO4 complexes exhibited improvement of ionic conductivity. However, their complexes showed decreased mechanical properties. The
improvement of ionic conductivity and mechanical properties could be obtained from the polymer electrolytes by using CRM.
The highest ionic conductivity of PEG/CRM/LiClO4/(EC-PC) was 5.33×10−4 S/cm at 25°C. 相似文献