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91.
A study was conducted to investigate the reduction and elimination of Escherichia coli O157:H7 by the effects of gamma irradiation and ozone treatment. Log phase cells were found to be more sensitive to gamma irradiation than stationary phase cells. E. coli O157:H7 was found to be considerably more resistant to irradiation at -18 degrees C than at 20 degrees C. The D values for this organism for treatment with ozone in tryptic soy agar were higher than those for treatment with ozone in phosphate buffer. Gamma irradiation at a dose of 1.5 kGy or ozone treatment at a concentration of 3 to 18 ppm for 20 to 50 min was required to assure the elimination of E. coli O157:H7. 相似文献
92.
T Byun T Uchida K Hirosawa F Mori H Oomori M Nagashima K Enta S Kodama S Kasahara K Iwade S Hosoda 《Canadian Metallurgical Quarterly》1997,29(5):243-250
No single musculoskeletal disorder has generated more passionate discussion than bone osteonecrosis. Surprisingly, its physiopathogenesis remains largely unknown despite in-depth studies. Its treatment is still debated, and its wide range of clinical manifestations which vary from totally asymptomatic to the catastrophic event of irreversible epiphyseal collapse remains a fascinating question for the clinicians (1-4). Magnetic Resonance (MR) imaging has given a large tribute to the discussion during the last decade by allowing detection of marrow infarcts at a presymptomatic period of the disease, thus providing data on its natural history. Unfortunately, MR imaging has also contributed to increase the confusion among various epiphyseal disorders. The aim of the current paper is to provide an overview of the current knowledge of imaging features by stressing accepted data and delineating blind areas. 相似文献
93.
The paper describes several improvements to a nonblocking copy network proposed previously for multicast packet switching. The improvements provide a complete solution to some system problems inherent in multicasting. The input fairness problem caused by overflow is solved by a cyclic running adder network (CRAN), which can calculate running sums of copy requests starting from any input port. The starting point can change adaptively in every time slot based on the overflow condition of the previous time slot. The CRAN also serves as a multicast traffic controller to regulate the overall copy requests. The throughput of a multicast switch can be improved substantially if partial service of copy request is implemented when overflow occurs. Call-splitting can also be implemented by the CRAN in a straightforward manner. Nonuniform distribution of replicated packets at outputs of the copy network may affect the performance of the following routing network. This output fairness problem due to underflow is solved by cyclically shifting the copy packets in every time slot. An approximate queueing model is developed to analyze the performance of this improved copy network. It shows that if the loading on each output of the copy network is maintained below 80%, the average packet delay in an input buffer would be less than two time slots 相似文献
94.
柔性有源OLED显示器制造几点技术方面的考虑 总被引:2,自引:0,他引:2
Juhn S. Yoo Nackbong Choi Yong-Chul Kim In-Hwan Kim Seung-Chan Byun Sang-Hoon Jung Jong-Moo Kim Soo-Young Yoon Chang-Dong Kim In-Byeong Kang In-Jae Chung 代永平 《现代显示》2009,20(2):21-24
AMOLED在柔性显示领域前途似锦。LG显示展示了一款全彩4in柔性AMOLED样机,衬底为80μm厚的不锈钢薄片,曲率达到5cm弯曲半径。本文就此项柔性显示技术所面临的挑战进行了探讨.包括柔性衬底衬底的传送、如何获得特性稳定可靠的TFT以使OLED的亮度和一致性适用于此项技术的商业化推广。 相似文献
95.
Woo‐Seok Cheong Jeong‐Min Lee Jong‐Ho Lee Sang‐Hee Ko Park Sung Min Yoon Chun‐Won Byun Shinhyuk Yang Sung Mook Chung Kyoung Ik Cho Chi‐Sun Hwang 《ETRI Journal》2009,31(6):660-666
We investigate the effects of interfacial dielectric layers (IDLs) on the electrical properties of top‐gate In‐Ga‐Zn‐oxide (IGZO) thin film transistors (TFTs) fabricated at low temperatures below 200°C, using a target composition of In:Ga:Zn = 2:1:2 (atomic ratio). Using four types of TFT structures combined with such dielectric materials as Si3N4 and Al2O3, the electrical properties are analyzed. After post‐annealing at 200°C for 1 hour in an O2 ambient, the sub‐threshold swing is improved in all TFT types, which indicates a reduction of the interfacial trap sites. During negative‐bias stress tests on TFTs with a Si3N4 IDL, the degradation sources are closely related to unstable bond states, such as Si‐based broken bonds and hydrogen‐based bonds. From constant‐current stress tests of Id = 3 µA, an IGZO‐TFT with heat‐treated Si3N4 IDL shows a good stability performance, which is attributed to the compensation effect of the original charge‐injection and electron‐trapping behavior. 相似文献
96.
Eui-Baek Byun Ha-Yeon Song Woo Sik Kim Jeong Moo Han Ho Seong Seo Sang-Hyun Park Kwangwook Kim Eui-Hong Byun 《International journal of molecular sciences》2021,22(14)
Although cisplatin is one of most effective chemotherapeutic drugs that is widely used to treat various types of cancer, it can cause undesirable damage in immune cells and normal tissue because of its strong cytotoxicity and non-selectivity. This study was conducted to investigate the cytoprotective effects of Cudrania tricuspidata fruit-derived polysaccharides (CTPS) against cisplatin-induced cytotoxicity in macrophages, lung cancer cell lines, and a mouse model, and to explore the possibility of application of CTPS as a supplement for anticancer therapy. Both cisplatin alone and cisplatin with CTPS induced a significant cytotoxicity in A549 and H460 lung cancer cells, whereas cytotoxicity was suppressed by CTPS in cisplatin-treated RAW264.7 cells. CTPS significantly attenuated the apoptotic and necrotic population, as well as cell penetration in cisplatin-treated RAW264.7 cells, which ultimately inhibited the upregulation of Bcl-2-associated X protein (Bax), cytosolic cytochrome c, poly (adenosine diphosphateribose) polymerase (PARP) cleavage, and caspases-3, -8, and -9, and the downregulation of B cell lymphoma-2 (Bcl-2). The CTPS-induced cytoprotective action was mediated with a reduction in reactive oxygen species production and mitochondrial transmembrane potential loss in cisplatin-treated RAW264.7 cells. In agreement with the results obtained above, CTPS induced the attenuation of cell damage in cisplatin-treated bone marrow-derived macrophages (primary cells). In in vivo studies, CTPS significantly inhibited metastatic colonies and bodyweight loss as well as immunotoxicity in splenic T cells compared to the cisplatin-treated group in lung metastasis-induced mice. Furthermore, CTPS decreased the level of CRE and BUN in serum. In summation, these results suggest that CTPS-induced cytoprotective action may play a role in alleviating the side effects induced by chemotherapeutic drugs. 相似文献
97.
Sung Nak-Yun Choi Jong-il Yoon Yohan Lee Soo-Young Byun Myung-Woo Hwang Yeoung-Jung Koenari Zubaidah Irawati Lee Ju-Woon Kim Jae-Hun 《Food science and biotechnology》2011,20(3):841-844
This study evaluated the anti-allergic effect of low molecular weight β-glucan (25 kDa) degraded by λ-irradiation. Allergy
was induced in mouse models administrated with λ-irradiated low molecular weight and non-irradiated high molecular weight
β-glucan, respectively, for 7 days. However, only the mice treated with low molecular weight β-glucan had a significantly
decreased the total serum IgE and ovalbumin specific-IgE levels, and significantly increased Th 1 cytokine expression compared
to only allergy induced mice. The allergic responses could be reduced by low molecular weight β-glucan treated λ-irradiation
through the increased expression of Th 1 response and decreased expression of total IgE and antigen specific IgE. 相似文献
98.
Seok-Chun Ko Min Cheol Kang Jung-Kwon Lee Hee-Guk Byun Se-Kwon Kim Seung-Cheol Lee Byong-Tae Jeon Pyo-Jam Park Won-Kyo Jung You-Jin Jeon 《European Food Research and Technology》2011,233(6):915-922
Angiotensin I-converting enzyme (ACE) inhibitory peptide was isolated from Styela plicata. The S. plicata was hydrolyzed with various proteases including Protamex, Kojizyme, Neutrase, Flavourzyme, Alcalase, trypsin, α-chymotrypsin,
pepsin, and papain. The hydrolysate prepared with Protamex had the highest ACE inhibitory activity compared to the other hydrolysates.
We attempted to isolate ACE inhibitory peptides from hydrolysate prepared with Protamex using ultra-filtration, gel filtration
on a Sephadex G-25 column and reversed-phase high-performance liquid chromatography (RP-HPLC) on an ODS column. IC50 value of the purified ACE inhibitory peptide was 24.7 μM, and Lineweaver–Burk plots suggest that the purified peptide from
S. plicata acts as mixed-type inhibitor against ACE. Amino acid sequence of the purified peptide was identified as Met-Leu-Leu-Cys-Ser,
with a molecular weight 566.4 Da. The results of this study suggest that peptides derived from S. plicata may be beneficial as anti-hypertension compounds in functional foods resource. 相似文献
99.
Bioactive properties of enzymatic hydrolysates from abdominal skin gelatin of yellowfin tuna (Thunnus albacares) 下载免费PDF全文
Yuna Han Sang‐Hun Byun Joung‐Hyun Park Seon‐Bong Kim 《International Journal of Food Science & Technology》2015,50(9):1996-2003
Gelatin (90.6 ± 0.1%) was optimally prepared by response surface methodology from yellowfin tuna (Thunnus albacares, YT) abdominal skin. To investigate bioactive properties of enzymatic hydrolysates from the abdominal skin gelatin (ASG), ASG was hydrolysed with alcalase, protamex, neutrase and flavourzyme as affected by hydrolysis time. Antioxidant, nitrite scavenging and angiotensin‐I converting enzyme (ACE) inhibitory activities of the hydrolysates were determined. Antioxidant activities of the hydrolysates were found through linoleic acid peroxidation inhibitory effects. Alcalase‐derived hydrolysates (AHs) were more effective than others in metal ions chelating, superoxide anion scavenging and hydroxyl radical scavenging activities (P < 0.05). AHs showed significantly stronger nitrite scavenging activities (44.4–60.7%) than others (P < 0.05). Fraction A from AH showed strong ACE inhibitory activity (IC50 of 0.75 mg mL?1). These results suggest that YT ASG and its enzymatic hydrolysates could be functional food and/or pharmaceutical ingredients with potent antioxidant, anticarcinogenic and antihypertensive benefits. 相似文献
100.
A resilient buffer allocation scheme in active queue management: a stochastic cooperative game theoretic approach 下载免费PDF全文
During the last decade, a plentiful number of active queue management schemes have been proposed, but their main objectives are simply allocating the buffer resource to all flows evenly, or protecting responsive flows from being degraded by unresponsive flows. However, the sending rates of the responsive flows can be determined diversely, and not all unresponsive flows have aggressively high sending rates. Furthermore, it is rational to reserve a portion of the buffer resource for certain privileged traffic. Grounded by these evidences, in this paper, we present a resilient active queue management algorithm, named Prior‐Core‐based Buffer Allocation considering diverse congestion control algorithms, fair‐unresponsive flows, and some privileged traffic. Our approach is based on stochastic cooperative game theory, where the payoffs yielded by cooperation are described by random variables, and the core is defined only over the distribution of these random payoffs; the core in this situation is called the prior‐core. As a result, it is shown that our buffer allocation, yielded by the prior‐core, achieves completely fair allocation for those flows whose requirement does not exceed the fair‐share regardless of the responsiveness, whereas aggressive flows are restricted according to availability of the buffer; all these are verified through ns‐2 simulation experiments. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献