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771.
Interfacial interactions underpin phenomena ranging from adhesion to surface wetting. Here, we describe a simple, rapid, and robust approach to modifying solid surfaces, based on an ultrathin cross-linkable film of a random copolymer, which does not rely on specific surface chemistries. Specifically, thin films of benzocyclobutene-functionalized random copolymers of styrene and methyl methacrylate were spin coated or transferred, then thermally cross-linked on a wide variety of metal, metal oxide, semiconductor, and polymeric surfaces, producing a coating with a controlled thickness and well-defined surface energy. The process described can be easily implemented and adapted to other systems. 相似文献
772.
773.
Lee Wonoh Kim Ji Hoon Shin Heon-Jung Chung Kwansoo Kang Tae Jin Youn Jae Ryoun 《Fibers and Polymers》2003,4(2):77-83
The cell modeling homogenization method to derive the constitutive equation considering the microstructures of the fiber reinforced
composites has been previously developed for composites with simple microstructures such as 2D plane composites and 3D rectangular
shaped composites. Here, the method has been further extended for 3D circular braided composites, utilizing B-spline curves
to properly describe the more complex geometry of 3D braided composites. For verification purposes, the method has been applied
for orthotropic elastic properties of the 3D circular braided glass fiber reinforced composite, in particular for the tensile
property. Prepregs of the specimen have been fabricated using the 3D braiding machine through RTM (resin transfer molding)
with epoxy as a matrix. Experimentally measured uniaxial tensile properties agreed well with predicted values obtained for
two volume fractions. 相似文献
774.
Abiotic stress confers serious damage to the photosynthetic machinery, often resulting in plant growth inhibition. Hypothetical chloroplast open reading frame 3 (Ycf3)-interacting protein 1 (Y3IP1) is a nucleus-encoded thylakoid protein and plays an essential role in the assembly of photosystem I. The full-length cDNA over-expresser (FOX) gene-hunting system is an approach using systemically generated gain-of-function mutants. Among the FOX-rice lines, a line CE175 overexpressing rice Y3IP1 gene (OsY3IP1) displayed less inhibition of root growth under saline (NaCl) stress. The expression of OsY3IP1 was up-regulated under saline and alkaline (Na2CO3) stresses in the rice variety Kitaake. After saline and alkaline treatments, transgenic Kitaake overexpressing OsY3IP1-GFP (OsY3IP1-GFPox/Kit) displayed higher levels of chlorophyll content compared to Kitaake. Under the stress conditions, the maximum quantum yield of photosystem II photochemistry levels was higher in OsY3IP1-GFPox/Kit than in Kitaake. The increased tolerance conferred by OsY3IP1 overexpression correlated with reduced reactive oxygen species accumulation. Our data provide new insights into the possible role of OsY3IP1 in the pathway suppressing photooxidative damage under stress conditions. These features can be further exploited to improve saline and alkaline tolerances of rice plants in future. 相似文献
775.
776.
Fakir Shahidullah Tareq Min Ah Lee Hyi-Seung Lee Jong-Seok Lee Yeon-Ju Lee Hee Jae Shin 《Marine drugs》2014,12(2):871-885
Concerning the requirements of effective drug candidates to combat against high rising multidrug resistant pathogens, we isolated three new linear lipopeptides, gageostatins A–C (1–3), consisting of hepta-peptides and new 3-β-hydroxy fatty acids from the fermentation broth of a marine-derived bacterium Bacillus subtilis. Their structures were elucidated by analyzing a combination of extensive 1D, 2D NMR spectroscopic data and high resolution ESIMS data. Fatty acids, namely 3-β-hydroxy-11-methyltridecanoic and 3-β-hydroxy-9,11-dimethyltridecanoic acids were characterized in lipopeptides 1 and 2, respectively, whereas an unsaturated fatty acid (E)-7,9-dimethylundec-2-enoic acid was assigned in 3. The 3R configuration of the stereocenter of 3-β-hydroxy fatty acids in 1 and 2 was established by Mosher’s MTPA method. The absolute stereochemistry of amino acid residues in 1–3 was ascertained by acid hydrolysis followed by Marfey’s derivatization studies. Gageostatins 1–3 exhibited good antifungal activities with MICs values of 4–32 µg/mL when tested against pathogenic fungi (R. solani, B. cinerea and C. acutatum) and moderate antibacterial activity against bacteria (B. subtilis, S. aeureus, S. typhi and P. aeruginosa) with MICs values of 8–64 µg/mL. Futhermore, gageostatins 1–3 displayed cytotoxicity against six human cancer cell lines with GI50 values of 4.6–19.6 µg/mL. It is also noteworthy that mixed compounds 1+2 displayed better antifungal and cytotoxic activities than individuals. 相似文献
777.
Kowarik M Numao S Feldman MF Schulz BL Callewaert N Kiermaier E Catrein I Aebi M 《Science (New York, N.Y.)》2006,314(5802):1148-1150
N-linked protein glycosylation is found in all domains of life. In eukaryotes, it is the most abundant protein modification of secretory and membrane proteins, and the process is coupled to protein translocation and folding. We found that in bacteria, N-glycosylation can occur independently of the protein translocation machinery. In an in vitro assay, bacterial oligosaccharyltransferase glycosylated a folded endogenous substrate protein with high efficiency and folded bovine ribonuclease A with low efficiency. Unfolding the eukaryotic substrate greatly increased glycosylation. We propose that in the bacterial system, glycosylation sites are located in flexible parts of folded proteins, whereas the eukaryotic cotranslational glycosylation evolved to a mechanism presenting the substrate in a flexible form before folding. 相似文献
778.
779.
The effect of pelleting on in situ rumen degradability of compound feed containing brown rice for dairy cows
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Shin‐ichi Tagawa Norio Yoshida Yukihiro Iino Ken‐ichi Horiguchi Toshiyoshi Takahashi Maria Watanabe Kei Takemura Syuhei Ito Toyoji Mikami 《Animal Science Journal》2017,88(1):185-189
This study was conducted to determine the effect of pelleting on in situ dry matter degradability of pelleted compound feed containing brown rice for dairy cows. Mash feed of the same composition was used as a control and the in situ study was conducted using three non‐lactating Holstein steers fitted with a rumen cannula. The feeds contained 32.3% brown rice, 19.4% rapeseed meal, 11.4% wheat bran and 10.6% soybean meal (fresh weight basis). Except for moisture content, the chemical composition of the feed was not affected by pelleting. In situ dry matter disappearance of the feed increased from 0 to 2 h and after 72 h of incubation with pellet processing. Integration of the dry matter disappearance values over time revealed that degradability parameter a (soluble fraction) increased with pellet processing, whereas parameter b (potentially degradable fraction) decreased. Parameter c (fractional rate of degradation) and effective degradability (5% passage rate) were not affected by pellet processing. We concluded that pellet processing promotes rumen degradability at early incubation hours when the pelleted feed contains brown rice. 相似文献
780.
Development of an in vitro oviduct epithelial explants model for studying sperm–oviduct binding in the buffalo
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KK Saraf A Kumaresan S Nayak S Chhillar L Sreela S Kumar UK Tripathi TK Datta TK Mohanty 《Reproduction in domestic animals》2017,52(4):687-691
In this study, we developed an in vitro model for studying sperm–oviduct binding in the buffalo. Oviduct explants were prepared by overnight culture of epithelial cells in TCM‐199 medium under 5% CO2 at 38.5 °C. Cryopreserved spermatozoa from buffalo bulls (n = 4) were incubated with the oviduct explants, and the sperm–oviduct explants complex was stained with JC‐1. The effect of sperm concentration (2, 3 and 4 million), size of the oviduct explants (<0.2, 0.2–0.3, 0.3–0.4 and >0.4 mm2) and time of incubation (1 hr and 4 hr) on binding index (BI—number of sperm bound to unit area of explants) was studied. No significant difference was observed in the BI among <0.2, 0.2–0.3 and 0.3–0.4 mm2 size of explants; however, the BI decreased significantly (p < .05) when the size of explants exceeded 0.4 mm2. The BI decreased significantly (p < .05) when the sperm concentration was increased to 4 million, while the duration of incubation did not have any significant effect on the BI. The interaction of bulls with explants size, sperm concentration and incubation time was not significant. The developed assay has the potential to be used as an in vitro model for studying sperm–oviduct binding in the buffalo. 相似文献