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991.
Caulerpa lentillifera inhibits protein-tyrosine phosphatase 1B and protects pancreatic beta cell via its insulin mimetic effect 总被引:1,自引:0,他引:1
Food Science and Biotechnology - The aim of this study was to determine whether Caulerpa lentillifea extract (CLE) can protect pancreatic beta cells and enhance insulin signaling in adipocytes. We... 相似文献
992.
Sung Hee Han Bong Soo Ko So Hyun Ahn Dong Ouk Noh Hyung Joo Suh 《International Journal of Food Science & Technology》2017,52(6):1417-1424
We investigated the explosive process effect on antioxidant activities of coffee bean. The total polyphenol contents of powdered extract of explosive puffing coffee bean at 0.75 MPa (PEP 7.5) and powdered extract of explosive puffing coffee bean at 0.9 MPa (PEP 9.0) were at a significantly higher than that of the powdered extract of roasting coffee bean (PER) (P < 0.05). PEP 7.5 showed the highest levels of 3‐CQA (86.23 μg mg?1), 4‐CQA (43.71 μg mg?1), and 5‐CQA (31.66 μg mg?1), and PEP 9.0 had also similar levels of chlorogenic acids, with 3‐CQA (77.99 μg mg?1), 4‐CQA (43.71 μg mg?1), and 5‐CQA (30.32 μg mg?1). PEP 7.5 and PEP 9.0 showed relatively higher antioxidant capacities in DPPH, ABTS, taurine, FRAP, and β‐carotene/linoleic acid assays. PEPs partly recovered the HepG2 cell damage induced by t‐BOOH. These results suggest that puffed coffee has beneficial health effects, and could be used for the development of novel processed coffee products. 相似文献
993.
Gun Joo Jung Sung Ki Song Young Chull Ahn Geun Sug Oh Young Bin Im 《Journal of Mechanical Science and Technology》2011,25(2):503-512
This research has investigated physical variables affecting indoor thermal comfort and subjective responses of thermal comfort
of students in a university in Korea in which the weather is oceanic temperate climate, and has been performed to contribute
to the research fields of Sustainable Thermal Standard and Adaptive Thermal Comfort (ATC). This research is based on the ISO
7730-2005 standard and the ATC theories and 4 main variables of PMV such as dry bulb temperature (Ta), relative humidity (RH),
black bulb temperature (Tg), and air velocity (Va) are measured once a week during two regular semesters. A clothing insulation,
a thermal sensation vote (TSV), an acceptability of thermal environment, and a preference for cooling and heating are investigated
at the same time using a questionnaire. This study was carried out for 26 weeks during the spring season, from March to June
2009, and the autumn season, from September to December 2009. The main achievements of this study are as follows. Monthly
Mean Outdoor Temperature (MMOT) and Operative Temperature (OT) in the classroom during research periods are 7.4∼23.3°C and
17.5∼29.0°C, respectively. The acceptability ratio of thermal environment shows over 80% when the range of OT in the classroom
is 17∼25°C, and the range can be applicable to operative index of heating and cooling of classroom. The mean TSV of respondents
is almost “neutral (0)” when the PMV in the classroom moves to “neutral (0)” and “slightly cool (−1)”, and the TSV is almost
“+1.5” when the PMV moves to “slightly warm (+1)”. The acceptability ratio of thermal environment is slightly different from
ASHRAE Standard 55-2004. So it is necessary to more investigate standard range of acceptability of thermal environment in
oceanic temperate climate region using much more databases. 相似文献
994.
Won So Young-Hun Kim Chang Jun Lee Dongil Shin En Sup Yoon 《Korean Journal of Chemical Engineering》2011,28(3):656-666
Accidents involving domino effects are more serious than other type of accidents. Although there have been studies on such
accidents, it is still difficult to examine the actual factors and causes since the domino effect is influenced nonlinearly
by factors involving flame, overpressure, and flying objects. We considered the case of adding new facilities to an existing
system in a given site. The layout of new facilities suggests positions that minimize the domino effects, based on nonlinear
optimization taking domino factors into account. We quantitatively calculated the domino risk of each facility through the
concept of combined domino factors (flame, overpressure, and missile). Also, we identified variations of domino damage extent
of the target system through comparison of the impacts of domino effect when additional facilities were installed. Simulated
annealing was adopted for searching optimal positions. As a case study, we applied the proposed method to the case of adding
DME storage tanks in the existing LPG charging facilities. The presented framework of the quantitative assessment of domino
risk and safety standard for the layout of additional facilities would be useful for proper layout design for improved accident
prevention. 相似文献
995.
Sung Joon Shin Jae Hyup Lee Jungwon So Kyungdan Min 《Journal of materials science. Materials in medicine》2016,27(11):162
Poloxamer-based thermo-sensitive sol-gel has been developed to reduce the incidence of postoperative scar formation at the laminectomy site. The purpose of this study was to evaluate the anti-adhesive effect of poloxamer based thermo-sensitive sol-gel compared to hyaluronate based solution after laminectomy, using a rabbit model. A thermo-sensitive anti-adhesive with a property of sol-gel transition was manufactured by a physical mixture of Poloxamer188/407, Chitosan and Gelatin. The viscosity in different temperatures was assessed. 72 adult New Zealand rabbits underwent lumbar laminectomy and were randomly divided into experimental (treated with the newly developed agent), positive (treated with hyaluronate based solution), and negative control groups. Each group was subdivided into 1 and 4-week subgroups. Gross and histological evaluations were performed to assess the extent of epidural adhesion. The experimental group showed significantly higher viscosity compared to the positive control group and showed a significant increase of viscosity as the temperature increased. Gross evaluation showed no statistically significant differences between the 1- and 4-week subgroups. However, histologic evaluation showed significant differences both in 1- and 4-week subgroups. Although the 4-week histologic results of the experimental and the positive control subgroups showed no significant difference, both subgroups revealed higher value compared to the negative control subgroup with regard to the ratio of adhesion less than 50?%. The new poloxamer based thermo-sensitive agent showed superior efficacy over the hyaluronate based agent at 1?week postoperatively. At 4?weeks postoperatively, there were no statistically significant differences between the two agents, although both showed efficacy over the sham group. 相似文献
996.
Sung Woong Choi 《Numerical Heat Transfer, Part A: Applications》2017,71(4):402-422
In this study, the liquid–vapor mixture model was used for a numerical study of natural convective flow in a cryogenic tank with a capacity of 4.9?m3 under various conditions of heat flux and filling level to understand the early stages of convective flow phenomena and the consequent thermal stratification of cryogenic liquid. Two cryogens—liquefied natural gas (LNG) and liquefied nitrogen (LN2)—were compared to observe their effects. LN2 exhibited faster vaporization owing to its lower heat of vaporization. It was observed that higher heat flux and lower filling level led to faster vaporization and relatively vigorous heat transfer, showing early thermal stratification. 相似文献
997.
998.
In this paper, new in‐core self‐powered neutron detector emitter candidate materials, ie, vanadium, cobalt, and silver, have been examined in their lifetimes compared with the commonly used rhodium emitter. Using a new quantitative lifetime evaluation model, the lifetimes of vanadium and cobalt were determined to be longer than that of rhodium, but these materials were also shown to have the disadvantage of low signal intensities. Under normal operating conditions, we showed that rhodium emitter can be used for 2 cycles of pressurized water reactors (PWRs) with lifetime of 4.35 years, whereas silver can be used for 5 cycles of PWRs with lifetime of 8.04 years. Three sensitivity tests were performed for rhodium and silver about (1) the emitter size, (2) the fuel assembly burnup, and (3) the emitter temperature variations. From the test results, we observed that the lifetimes of rhodium and silver emitters remained 2 and 5 cycles long, respectively. We concluded that silver can significantly extend the in‐core detector's lifetime in PWR operation. 相似文献
999.
Kwonwoo Shin Rak-Kyung Park Lan Yu Chong-Yun Park Young Sil Lee Yun-Soo Lim Jong Hun Han 《Synthetic Metals》2011,161(15-16):1596-1599
This study sought to improve the characteristics of single-walled carbon nanotube (SWCNT) transparent conductive films (TCFs), such as their sheet resistance and transparency, by applying pre-treatments to their PET substrates. Oxygen–argon plasma pretreatment was found to increase the surface energies of the PET substrates from 33.9 to 74.2 mJ/m2, which improves the electric conductivity of the SWCNT-TCFs and provides a lower sheet resistance at a given light transmittance. Polymer electrolyte solution pretreatment was used to vary the surface functionality and modulate the surface charges quantitatively, as confirmed by the measurement of the resulting substrate zeta potentials, which varied between ?45.8 and 18.2 mV. When the surfaces became negatively charged through pretreatment, the electric conductivities of the SWCNT-TCFs were increased. Both pre-treatments also improve the adsorption of SWCNTs onto the PET substrates and reduce the loss of coating solution during the spray deposition of SWCNTs. 相似文献
1000.
Hee Mun Park Ji Young Choi Hyun Jong Lee Eui Yoon Hwang 《Construction and Building Materials》2009,23(1):219-225
This paper describes the results of laboratory and full-scale performance tests for a high durability asphalt binder (HDAB) and high durability asphalt mixture (HDAM) applicable to the wearing course in a bridge deck system. The HDAB was developed using a styrene–butadiene–styrene (SBS) modifier and hydrocarbon for improving construction workability and resistance to fatigue cracking. Various binder tests were conducted on the HDAB, and test results showed that the resistance to fatigue and low temperature cracking of the HDAB increased significantly compared to that of the PG 64-22 and PG 76-22 binders. For the mixtures, the fatigue test results showed that the HDAM has a three times longer fatigue life than the SBS-modified asphalt mixture. It was also found that the HDAM has a higher resistance against moisture-induced damage. Results from full-scale accelerated testing on the bridge deck pavement system proved that the HDAM can significantly improve pavement performance. 相似文献