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Perspective texture synthesis has great significance in many fields like video editing, scene capturing etc., due to its ability to read and control global feature information. In this paper, we present a novel example-based, specifically energy optimization-based algorithm, to synthesize perspective textures. Energy optimization technique is a pixel-based approach, so it’s time-consuming. We improve it from two aspects with the purpose of achieving faster synthesis and high quality. Firstly, we change this pixel-based technique by replacing the pixel computation with a little patch. Secondly, we present a novel technique to accelerate searching nearest neighborhoods in energy optimization. Using k- means clustering technique to build a search tree to accelerate the search. Hence, we make use of principal component analysis (PCA) technique to reduce dimensions of input vectors. The high quality results prove that our approach is feasible. Besides, our proposed algorithm needs shorter time relative to other similar methods. 相似文献
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Structural Insight of a Trimodular Halophilic Cellulase with a Family 46 Carbohydrate-Binding Module
Huaidong Zhang Guimin Zhang Chaoxiang Yao Muhammad Junaid Zhenghui Lu Houjin Zhang Yanhe Ma 《PloS one》2015,10(11)
Cellulases are the key enzymes used in the biofuel industry. A typical cellulase contains a catalytic domain connected to a carbohydrate-binding module (CBM) through a flexible linker. Here we report the structure of an atypical trimodular cellulase which harbors a catalytic domain, a CBM46 domain and a rigid CBM_X domain between them. The catalytic domain shows the features of GH5 family, while the CBM46 domain has a sandwich-like structure. The catalytic domain and the CBM46 domain form an extended substrate binding cleft, within which several tryptophan residues are well exposed. Mutagenesis assays indicate that these residues are essential for the enzymatic activities. Gel affinity electrophoresis shows that these tryptophan residues are involved in the polysaccharide substrate binding. Also, electrostatic potential analysis indicates that almost the entire solvent accessible surface of CelB is negatively charged, which is consistent with the halophilic nature of this enzyme. 相似文献
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Martin Bundi Mohammad Monir Shah Eric Odoyo Cyrus Kathiiko Ernest Wandera Gabriel Miring'u Sora Guyo Daniel Langat Kouichi Morita Yoshio Ichinose 《Microbiology and immunology》2019,63(9):350-358
Kenya is endemic for cholera with different waves of outbreaks having been documented since 1971. In recent years, new variants of Vibrio cholerae O1 have emerged and have replaced most of the traditional El Tor biotype globally. These strains also appear to have increased virulence, and it is important to describe and document their phenotypic and genotypic traits. This study characterized 146 V. cholerae O1 isolates from cholera outbreaks that occurred in Kenya between 1975 and 2017. Our study reports that the 1975–1984 strains had typical classical or El Tor biotype characters. New variants of V. cholerae O1 having traits of both classical and El Tor biotypes were observed from 2007 with all strains isolated between 2015 and 2017 being sensitive to polymyxin B and carrying both classical and El Tor type ctxB. All strains were resistant to Phage IV and harbored rstR, rtxC, hlyA, rtxA and tcpA genes specific for El Tor biotype indicating that the strains had an El Tor backbone. Pulsed field gel electrophoresis (PFGE) genotyping differentiated the isolates into 14 pulsotypes. The clustering also corresponded with the year of isolation signifying that the cholera outbreaks occurred as separate waves of different genetic fingerprints exhibiting different genotypic and phenotypic characteristics. The emergence and prevalence of V. cholerae O1 strains carrying El Tor type and classical type ctxB in Kenya are reported. These strains have replaced the typical El Tor biotype in Kenya and are potentially more virulent and easily transmitted within the population. 相似文献
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The formation of R-prime plasmids was selected in crosses involving soybean microsymbionts with genomic Tn5 insertions and carrying plasmid pJB3JI (with one IS2) copy as donors and Escherichia coli HB101 as recipient. Whereas the parent plasmid was 60 kb, recombinant plasmids between 76 kb and 121 kb were obtained. Restriction and Southern analyses confirmed the mobilization of Tn5 on four R-primes from Bradyrhizobium japonicum I-110 and on an R-prime plasmid from Rhizobium fredii HH303. The largest R-prime plasmid was obtained from the rescue of two symbiotically defective R. fredii mutant strains that required adenosine.Non-standard abbreviation TDP
transposon donor pool
Scientific article number A-4728 and contribution number 7724 of the Maryland Agricultural Experiment Station 相似文献
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Alkaline sucrose solution was demonstrated to be a good solvent for the solubilization of water-insoluble drugs. At high concentration
and alkaline pH, sucrose solubilizes water-insoluble molecules through intramolecular conformations. Tetracyline and chloramphenicol,
when dissolved in alkaline sucrose solution, retained their bactericidal activity. Gel permeation-chromatography analysis
and atomic-force-microscopy studies confirmed the formation of sucrose-antibiotics complex. 相似文献
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Receptors for estradiol, progesterone and dihydrotestosterone have been demonstrated in normal growing breasts of young females below 25 years. 相似文献