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991.
Seung-Won Jung Gi Hyun Park Eunjung Kim Kang Min Yoo Hea Won Kim Jin Soo Lee Min Youl Chang Kyong-Oh Shin Kyungho Park Eung Ho Choi 《International journal of molecular sciences》2022,23(7)
Stratum corneum (SC) pH regulates skin barrier functions and elevated SC pH is an important factor in various inflammatory skin diseases. Acidic topical formulas have emerged as treatments for impaired skin barriers. Sodium proton exchanger 1 (NHE1) is an important factor in SC acidification. We investigated whether topical applications containing an NHE1 activator could improve skin barrier functions. We screened plant extracts to identify NHE1 activators in vitro and found Melissa officinalis leaf extract. Rosmarinic acid, a component of Melissa officinalis leaf extract, significantly increased NHE1 mRNA expression levels and NHE1 production. Immunofluorescence staining of NHE1 in 3D-cultured skin revealed greater upregulation of NHE1 expression by NHE1 activator cream, compared to vehicle cream. Epidermal lipid analysis revealed that the ceramide level was significantly higher upon application of the NHE1 activator cream on 3D-cultured skin, compared to application of a vehicle cream. In a clinical study of 50–60-year-old adult females (n = 21), application of the NHE1 activator-containing cream significantly improved skin barrier functions by reducing skin surface pH and transepidermal water loss and increasing skin hydration, compared to patients who applied vehicle cream and those receiving no treatment. Thus, creams containing NHE1 activators, such as rosmarinic acid, could help maintain or recover skin barrier functions. 相似文献
992.
OPC客户端程序开发及其在集散控制系统中的应用 总被引:4,自引:3,他引:1
介绍在OPC规范下,开发OPC客户端数据访问程序的方法,并将开发的OPC客户端程序成功用于与集散控制系统CENTUM CS3000和Experion PKS的数据访问. 相似文献
993.
基于OPCHDA技术的历史数据通讯系统的实现 总被引:1,自引:1,他引:0
针对过程控制系统中历史数据通讯接口复杂、数据量大等特点,以OPCHDA技术为基础,构建了一个三层的历史数据通讯系统,并以FPSO历史数据通讯系统为例,详细论述了整个系统的实现过程及其关键技术,为过程控制系统的历史数据通讯提供了一个可行的解决方案. 相似文献
994.
Zhongwei Tan Xingguo Xu Yu Wan Chengjun Kang Zhaoqiang Zhang Zhenxia Zhao Fang Shen Kungang Chai Hongbing Ji 《中国化学工程学报》2022,49(9):150-160
Adsorptive recovery of valuable components from industrial wastewater is highly desirable for avoiding resource wastage but remains a challenge. Herein, we develop an efficient continuous adsorption process for recovering aromatic compounds in wastewater from styrene monomer and propylene oxide coproduction(SMPO) plant. Based on our insight into the potential of bio-based porous materials for adsorption application, starch-graft-polystyrene(SPS) and aryl-modified β-cyclodextrin(ACD) were prepare... 相似文献
995.
Comparison of the Antimicrobial and Sanitizer Resistance of Salmonella Isolates from Chicken Slaughter Processes in Korea 下载免费PDF全文
So Youn Youn Ok Mi Jeong Byung Kook Choi Suk Chan Jung Min Su Kang 《Journal of food science》2017,82(3):711-717
Salmonella is a foodborne pathogen worldwide. Outbreaks of Salmonella are commonly associated with consumption of contaminated foods such as poultry products. Therefore, the objective of this study was to determine the occurrence, biofilm formation, antibiotic resistance, and sanitizer resistance of Salmonella enterica isolated from chicken carcasses. A total of 318 samples were collected from 15 chicken slaughterhouses in 8 provinces of Korea. They were then examined for Salmonella contamination. S. enterica isolates were tested for their susceptibilities to 15 antimicrobials by broth microdilution method. Their biofilm formation ability and resistance to sanitizers were also evaluated. Eighty‐two isolates of S. enterica were obtained from the 318 samples. There were 14 serotypes and 2 untypable isolates. Fifty‐seven (69.5%) isolates were resistant to at least one antibiotic while 30 (36.6%) isolates were resistant to 5 or more antibiotics. Two S. Senftenberg and 3 S. Montevideo isolates exhibited considerable biofilm formation ability (A600>0.2) following incubation in Luria‐Bertani (LB) broth for 48 h. Biofilm cell survival and recovery growth assay after sanitization showed that most isolates were highly susceptible to 2.5% lactic acid and 0.1% cetylpyridinium chloride. Therefore, lactic acid and cetylpyridinium chloride might be alternatively or additionally used in addition to chlorine‐based sanitizers that are frequently used to reduce Salmonella contamination of chicken carcasses. Our results provide basic information on the distribution of Salmonella serotypes in chicken slaughterhouses. This study also highlights the necessity to improve farming practices and use antimicrobial agents cautiously. This study also suggests that sanitization during the slaughtering process might be necessary to reduce Salmonella contamination of chicken carcasses. 相似文献
996.
Eun Jung Cho Xiang Lan Piao Moon Hee Jang Seung Hoon Baek Hyun Young Kim Ki Sung Kang Sung Won Kwon Jeong Hill Park 《Food chemistry》2008
This study was carried out to investigate changes in the free amino acid contents and antioxidant activity of Panax ginseng induced by steaming at different temperatures. For this purpose, white ginseng (WG), red ginseng (RG, ginseng steamed at 100 °C) and ginseng steamed at 120 °C (SG) were prepared using an autoclave. Most free amino acids were decreased significantly by steam treatment, with the greatest reduction observed in SG. Total content of free amino acids, 17.9 mg/g in WG was reduced to 12.2 mg/g in RG and 2.79 mg/g in SG. As for Arg which is the most predominant amino acid in ginseng, the content, 10.4 mg/g in WG, decreased significantly to 1.38 mg/g in SG. In particular, β-N-oxalyl-L-α,β-diaminopropionic acid (β-ODAP), a well-known neurotoxin, was reduced by 92.9% in SG. In contrast, the level of Maillard reaction products (MRPs) increased with steam treatment, which indicates that the reduction of most amino acids is attributed to the extent of the Maillard reaction. Based on MRPs being useful antioxidants, we assayed the scavenging activity against free radicals produced by 2,2′-azobis-(2-amidinopropane) dihydrochloride (AAPH). The radical scavenging activity of a ginseng extract increased with steam treatment, with the most potent activity in SG. Further, MRPs-rich fraction in SG showed powerful antioxidant activity, which indicates MRPs are major contributors to antioxidant activity enhanced by steam treatment. 相似文献
997.
针对基于RFID(射频识别)的稻米质量安全追溯系统这一复杂系统过程。用系统分析的方法将其划分为3个逻辑上个独立的流程和7个互有联系的功能环节(节点)。对该7个环节进行了FMECA(故障模式影响及危害性分析)分析。在确定FMECA风险模式的危害度时采用的是危险顺序数法(Risk Priority Number)。考虑到基于RFID的稻米质量安全追溯过程的特殊性,引入模糊综合评价方法并参照调查和历史数据分别计算了7个功能环节的RPN值。通过确定RPN,明确了稻米质量安全追溯过程中各环节出现风险的种类和发生概率,并提出预防的措施;量化了基于RFID稻米质量追溯过程的风险,使风险控制具有可操作性。 相似文献
998.
Sung Ho Oh Jae Gun Han Young Kim Ji Hye Ha Seung Seop Kim Myoung Hoon Jeong Hyang Suk Jeong Na Young Kim Jeong Sub Cho Won Byong Yoon Shin Young Lee Do Hyung Kang Hyeon Yong Lee 《Journal of Bioscience and Bioengineering》2009,108(5):429-434
Autotrophic growth of Porphyridium cruentum under 18:12 h and 12:12 h light:dark cycles showed the maximum cell concentration of 2.1 g-dry wt./L, whereas the specific growth rate, 0.042 (1/h), at 18:6 h is faster than that of 12:12 h, 0.031 (1/h), respectively. The highest lipid accumulation level, 19.3 (%, w/w), was achieved at 12:12 h cycle. Under dark cultivation condition with 10 g/L of glucose, the lipid accumulation in the cell was 10.9 (%, w/w), whereas the heterotrophic growth with glycerol as the carbon resource showed low level of cell concentration and lipid production, compared to that of glucose. The glucose was decided to be a suitable carbon resource for the heterotrophic growth of P. cruentum. The lipids from P. cruentum seemed be feasible for biodiesel production, because over 30% of the lipid was C16–C18:1. The cultivation time and temperature were important factors to increase the maximum cell concentration. Extending the cultivation time helps maintain the maximum cell concentration, and higher lipid accumulation was achieved at 25 °C, compared to 35 °C. The fed-batch cultures showed that, under the light condition, the specific production rate was slightly decreased to 0.4% lipid/g-dry wt./day at the later stage, whereas, under the dark condition, the specific production rate was maintained to be a maximum value of 1.1% lipid/g-dry wt./day, even in the later stage of cultivation. The results indicate that the heterotrophic or 12:12 h cyclic mixotrophic growth of P. cruentum could be used for the production of biodiesel in long-term fed-batch cultivation of P. cruentum. 相似文献
999.
热死环丝菌生长预测模型的建立 总被引:6,自引:0,他引:6
针对引起冷却肉腐败的优势微生物热死环丝菌,以分离得到的S-8菌株作为受试菌株,研究了0~10℃低温条件下热死环丝菌S-8的生长情况。利用SAS程序拟和不同温度条件下的生长情况,经过比较发现,Gompertz模型比线性模型能更好地拟合热死环丝菌的生长,从而得到了其生长的Gompertz模型参数;利用平方根模型对其的最大比生长速率平方根-温度(U(1/2)-T)进行拟合,得到热死环丝菌S-8生长的二级模型:U(1/2)=0.1192(T+6.00),T∈[0,10];利用培养基数据,冷却肉产品数据和温度波动条件下的数据对所得到的二级模型进行验证,计算得到总的偏差因子和准确因子分别为0.982和1.223,结果表明二级模型能真实快速有效地预测冷链条件下冷却肉中热死环丝菌的生长。 相似文献
1000.
Yan Kang Long Li Wanchao Chen Feiyu Zhang Yiping Du Ting Wu 《Food Analytical Methods》2018,11(11):3161-3169
A structure of polyurethane micelle/Ag nanoparticle (Ag NP) cluster was fabricated as surface-enhanced Raman scattering (SERS) substrate for in situ extracting organic compounds on the surface of different matrixes, in which polyurethane micelles acted as the host material to capture target molecules and stabilize nanoparticle cluster. This method provided stable aqueous suspensions of Ag NP cluster due to the amphiphilic properties of polyurethane. We demonstrated SERS-based in situ detection of pesticides on vegetables and fruit skin, by simply dropping polyurethane micelle/Ag NPs substrate on the sample surface where the target molecules could be detected without a previous elution and extracting. The obtained results showed that this polyurethane micelle/Ag NP cluster substrate had excellent SERS performance for pesticide molecules with ideal stability and reproducibility. With further optimization, the limit of detection of 0.03 μg/mL acetamiprid, 0.08 μg/mL phosmet, and 0.002 μg/mL thiabendazole was obtained, respectively. 相似文献