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991.
Suk Ho Bhang Woo Soon Jang Jin Han Jeong‐Kee Yoon Wan‐Geun La Eungkyu Lee Youn Sang Kim Jung‐Youn Shin Tae‐Jin Lee Hong Koo Baik Byung‐Soo Kim 《Advanced functional materials》2017,27(1)
Current treatments for wound healing engage in passive healing processes and rarely participate in stimulating skin cell behaviors for active wound healing. Electric potential difference‐derived electrical fields (EFs) are known to modulate skin cell behaviors. Here, a piezoelectric dermal patch is developed that can be applied on skin wound site and EF is generated to promote wound healing. The one‐directionally aligned zinc oxide nanorod‐based piezoelectric patch generates piezoelectric potential upon mechanical deformations induced by animal motion, and induces EF at the wound bed. In vitro and in vivo data demonstrate that the piezoelectric patch promotes the wound healing process through enhanced cellular metabolism, migration, and protein synthesis. This modality may lead to a clinically relevant piezoelectric dermal patch therapy for active wound healing. 相似文献
992.
Jaehoon Park Lu J.W. Boesch D.S. Stemmer S. York R.A. 《Microwave and Wireless Components Letters, IEEE》2006,16(5):264-266
A monolithic Ku-band phase shifter employing voltage tunable Bi/sub 1.5/Zn/sub 1.0/Nb/sub 1.5/O/sub 7/ (BZN) thin film parallel plate capacitors is reported. BZN films were deposited by radio frequency magnetron sputtering on single-crystal sapphire substrates. A nine-section distributed coplanar waveguide loaded-line phase-shifter structure was designed. A differential phase shift of 175/spl deg/ was achieved with a maximum insertion loss of 3.5 dB at 15 GHz, giving a figure of merit /spl sim/50/spl deg//dB. To the best of our knowledge, this is the first demonstration of a monolithic tunable microwave circuit using BZN thin films. 相似文献
993.
The objective of this study was to investigate the effect of mungbean protein isolate (MPI) on the potential possibility of water binding agent and as a substrate for the microbial transglutaminase (MTGase) in myofibrillar protein. Cooking loss (CL,%), gel strength (GS, gf), sodium dodecyl sulphate‐polyacrylamide gel electrophoresis (SDS‐PAGE), differential scanning calorimetry (DSC) and scanning electron microscopy (SEM) were measured. The addition of MPI reduced CL, indicating that it has a water binding capacity during cooking. The major protein band (53 kDa) of MPI appeared when MPI was mixed with MP, but it disappeared when MTGase was incorporated. MPI treatment changed the endothermic peaks as compared with those of CTL. MTGase (1%) mediated pork MP increased CL and GS (P < 0.05), and reduced peak temperatures with vanishing of endothermic intensity at 1st and 3rd peaks, suggesting the structural changes of protein gelation. In microstructures, MTGase treatment showed a finely stranded structure in MP gels, while MPI showed a conglomerated surface in MTGase‐mediated MP gels. These results indicated that MPI appears to be a water binding agent during cooking and function as a substrate for MTGase in MP gelation. 相似文献
994.
The objective of this study was to evaluate the gelling properties of pork myofibrillar protein (MP) gels at various salt concentrations with or without curdlan, and its application to model sausages with reduced salt levels. When curdlan was incorporated into MP mixtures, cooking yield (CY) at 0.15 m salt was similar to that of 0.45 m salt (P > 0.05). Gel strength of MPs at 0.45 m salt was highest among other salt concentrations. Increased salt concentration tended to be high shear stress values, regardless of the presence of curdlan (P < 0.05). MP gels with increasing salt concentration showed fewer pores and swollen structures. Addition of curdlan improved CY and expressible moisture of low-fat model sausage with increased salt levels. The addition of curdlan at 1.0% salt reduced the hardness and gumminess, and similar to those at 1.5% without curdlan. These results indicated that curdlan improved the water-holding capacity and textural properties of low-fat and low-salt sausage. 相似文献
995.
996.
Toxigenic Staphylococcus aureus contamination in ready-to-eat (RTE) food is a leading cause of foodborne illness in Korea. To monitor food contamination by S. aureus, a total of 3332 RTE food samples were selected from nationwide wholesale marts between 2003 and 2004 and examined. A total of 285 (8.6%) of the overall samples were contaminated by S. aureus. According to the analysis, 31.6% of the tested cream-cakes, 19.8% of the raw fish, and 19.3% of the rice cakes with filling were contaminated with S. aureus. Forty-seven percent of the strains isolated from the contaminated food were enterotoxigenic S. aureus. The phenotypic result of the strain isolated from food showed that 48% of the strains produced one or more toxins, such as staphylococcal enterotoxins A, B, and C (SEA, SEB, and SEC). At least one SEA was produced by over 90% of the toxigenic strains. Other toxins, such as SEB, SEC, SED, SEA+SEC, and SEC+SED, were each detected. Toxic shock syndrome toxin 1 (TSST-1), a causative agent of toxic shock syndrome, was detected in 13 strains of the toxigenic isolates from the food. As the result of genotyping, 22 strains with a toxin gene that was not detected in the phenotypic analysis were also detected. Sixty-nine percent of the toxigenic strains had at least one sea gene, and the most prevalent genotype was sea+seh (34.4%), followed by sea (18.8%) and sea+seg+sei (15.6%). The tst gene encoding TSST-1 was found in 13 strains (13.5%). The genes (eta and etb) encoding exfoliative toxins A and B were not detected in any of the samples. 相似文献
997.
Kee Young Koo Min Guk Park Un Ho Jung Sung Hyun Kim Wang Lai Yoon 《International Journal of Hydrogen Energy》2014
A highly dispersed 50 wt% Ni/MgO–Al2O3 catalyst was prepared by deposition–precipitation (DP) method for the diesel pre-reforming reaction. The pH of the precursor solution was controlled from pH 9.5 to 12.0 to examine the effects on NiO crystallite size and metal dispersion. The increase of pH of the precursor solution causes an increase of specific surface area and metal dispersion, and reduces NiO crystallite size. The pre-reforming reaction was carried out using n-tetradecane as surrogate compound of diesel. The coke formation of used catalysts was examined by TGA, TEM, SEM, and Raman analysis. The 50 wt% Ni/MgO–Al2O3 catalyst prepared at pH 11.5 showed a high catalytic activity and excellent coke resistance due to high metal dispersion (8.71%), small NiO crystallite size (3.5 nm), and strong interaction between Ni and support. Furthermore, this catalyst showed a good stability in the pre-reforming reaction at S/C ratio of 3.5 and 450 °C for 88 h. 相似文献
998.
Effects of graphene counter electrode and CdSe quantum dots in TiO2 and ZnO on dye‐sensitized solar cell performance 下载免费PDF全文
Fabrication and performance study of dye‐sensitized solar cells using different counter electrodes and photoanodes is reported. Spin coated, E‐beam coated platinum, and graphene electrodes were used as counter electrodes. Different combinations of TiO2 nanoparticle and ZnO nanorods (NRs) with CdSe quantum dots were prepared and used as photoanodes. The photoanodes comprising of both ZnO NRs and TiO2 nanoparticles have shown improved performances in short‐circuit current density and open‐circuit voltage comparing the devices fabricated using only ZnO NR or TiO2 nanoparticles. The inclusion of CdSe quantum dots has been found to increase the performance of dye‐sensitized solar cell for all the photoanodes. In case of counter electrodes, the cells fabricated with graphene showed improved performance. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
999.
Sang Gil Lee Terrence M. Vance Tae-Gyu Nam Dae-Ok Kim Sung I. Koo Ock K. Chun 《Sensing and Instrumentation for Food Quality and Safety》2016,10(3):562-568
The present study evaluated the accuracy of pH differential (PD) method and HPLC method expressed as cyanidin-3-glucoside equivalent (CGE) for measuring total anthocyanin (TA) contents of five berries. Major anthocyanins of blueberry, blackberry, black currant, raspberry, and cranberry were analyzed with quantitative HPLC (q-HPLC) method using individual anthocyanin standards and used as a standard reference of comparison. PD method and HPLC method showed similar trend, although absolute amounts of TA differed in blueberry and cranberry. However, data showed that the TA of black currant and raspberry expressed as CGE considerably deviated from those obtained by q-HPLC. This discrepancy was due to underestimating TA of these two berries which contain disaccharides as major glycones, when expressed as CGE. On the other hand, when expressed as their major anthocyanin equivalents, TA of these two berries showed better approximate values with those by q-HPLC method. In addition, this finding was confirmed by Bland–Altman analysis. Our findings demonstrated that the type of glycone in berries is a critical factor to cause discrepancy between TA as CGE and actual TA and should be considered for measuring TA contents. 相似文献
1000.
Jung WK Lim JY Kwon NH Kim JM Hong SK Koo HC Kim SH Park YH 《International journal of food microbiology》2007,113(1):102-107
Enterococci for which the minimum inhibitory concentration (MIC) of vancomycin was >/=8 mg/l were isolated from meat, feces, and raw milk samples collected in Korea from March to November 2003. Among the 243 vancomycin-resistant enterococci (VRE) that were identified the vanA vancomycin resistance gene was carried by 51 Enterococcus faecium and one Enterococcus sp., vanC1 was carried by 151 Enterococcus gallinarum, vanC2 was carried by 39 Enterococcus casseliflavus, and one Enterococcus sp. carried no van genes. Of the isolated enterococci carrying vanA, 4% were found to be highly resistant to gentamicin and 11% were resistant to ampicillin. Further genotyping of the E. faecium isolates carrying vanA using pulsed-field gel electrophoresis (PFGE) revealed extensive heterogeneity. The vancomycin resistance transferability test revealed that only two of the 52 enterococci carrying the vanA gene were able to transfer vancomycin resistance to other enterococci. The VRE were recovered from various animal sources with a particularly high prevalence of E. faecium carrying the vanA gene being found in poultry meat. 相似文献