• Polymer(Korea)
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• v.37 no.4
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• pp.500-506
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• 2013

The effect of compatibilizer types on the properties of polyphenylene sulfide (PPS)/polyethylene terephthalate (PET) blends was investigated. The blends were extruded by a single screw extruder attached with a Maddock mixing zone and their molded properties were examined. As a basic blend composition, a linear PPS/PET (40/60) blend was selected based on cost efficiency. Three types of compatibilizer, SEBS, modified SEBS, and modified PS were added to the basic blend to improve the properties. The thermal, rheological, mechanical properties and the morphology of the ternary blends were analyzed. The maximum mechanical properties of blends was found at 1 phr of m-SEBS or m-PS content, whose values were almost the same as the theoretical values of miscible blend system. It seemed to by the case that the partial reaction between compatibilizer and the basic blend caused the enhancement of compatibility between linear PPS and PET phases. These ternary blends would be applicable as economic linear PPS alloys.

• Journal of the Microelectronics and Packaging Society
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• v.25 no.4
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• pp.35-40
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• 2018

Simple and useful synthetic process to control the morphology of block copolymers (BCPs) is required for implementation in various device applications. However, the conventional method to use colloidal templates is not enough to realize the production of pure and massive core-shell nanoparticles due to the cost-intensive complex process. Here, we introduce a novel and facile synthesis method to realize the formation of core-shell $SiO_x$ nanoparticle power by employing an immersion annealing of a sphere-forming poly(styrene-b-dimethylsiloxane) (PS-b-PDMS) BCP. We successfully obtained a PS-encapsulated $SiO_x$ nanoparticle with a diameter of ~20 nm. In addition, we analyzed how the mixing ratio of heptane/ethanol affects the BCP morphology of self-assembled PS-b-PDMS nanoparticles, showing a worm-like structure under the optimum immersion conditions. This useful approach is expected to be extendable to other solvent-based BCP synthesis, providing a new guideline for unique BCP production.

• Herbal Formula Science
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• v.30 no.4
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• pp.269-280
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• 2022

Objectives : In this study, it was investigated the effects of solid-phase fermentation extraction with Phellinus linteus of discarded Schisandra chinensis extract (PS) and its action mechanism on dexamethasone-induced muscle atrophy in mice. Methods : In mice, muscle atrophy model was induced by dexamethasone (5 mg/kg, I.p) once daily for 2 weeks and with PS extract administration (100 and 300 mg/kg, p.o.) as treatment groups. The changes in body weights, grip strength, Treadmill test, muscle weights, and the expression of atrophy-related genes were measured in muscle atrophy mice. The histological changes of gastrocnemius tissues were also observed by H&E staining with measurement of myofiber size. Results : The administration of PS extract increased significantly body weights, grip strength, treadmill test and muscle weights in muscle atrophy mice. PS extract administration increased significantly the area of myofibers and inhibited structural damages of muscle and increased significantly the expression of myogenin and decreased significantly the expression of MuRF1, Atrogin1 and phosphorylation of AMPK and PGC1α in muscle tissues of muscle atrophy mice. Conclusions : These results indicate that PS extract has a improvement effects on muscle atrophy with stimulation of myogenic differentiation and inhibition of mRNA degradation that could be related with the activation of AMPK and PGC1α signaling pathways in muscle. This suggests that PS extract can apply to treat muscle atrophy in clinics.

• Asian Journal of Turfgrass Science
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• v.17 no.1
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• pp.19-33
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• 2003

The objective of this study was to evaluate the effects of crumb rubber recycled from used tires as a soil incorporation and topdressing materials on a trafficked Korean lawngrass‘Zenith’(Zoysia japonica). In Exp 1, incorporation treatments included three particle sizes (PS: coarse =4∼6.35 mm, medium =2∼4 mm, and One : less than 2 mm in diameter) and two incorporation rate (IR: 10 and 20%). Wear treatments were applied 30 passes per day by compactor weights being 60 kg with soccer shoes. Topdressing treatments included three PS and two topdressing depth (TD: 5 and 10 mm). Wear treatments were the same as described in Exp 1. In Exp 1, the treatment with medium PS+IR 20 resulted in the tendency to have high total clipping yield. There was no significant difference in clipping yield, turfgrass visual color, coverage, and root length among the treatments. Compared to control, tissue Zn levels increased about 6.5-fold by the treatments. The treatment with fine PS +IR 20 caused a less peak deceleration than coarse PS +IR 10. Total porosity, air-filled porosity, and capillary porosity increased with fine PS +IR 20. In Exp 2, compared to controls, however, there was a difference in turfgrass visual color after the termination of traffic treatment. There was no difference in root length. The treatment with fine PS + TD 10 resulted in the highest total clipping yield. As a result of soil physical analysis, soil penetration resistance was reduced by the treatments. The treatment with coarse PS resulted in a less peak deceleration than fine PS. In conclusion, turfgrass growth was increased by crumb rubber incorporation which enhanced soil physical properties. The crumb rubber topdressing was able to cushion the crown tissue area while still providing a smooth and uniform surface, improve overall turfgrass quality, and reduce compaction.

• The Korea Journal of Herbology
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• v.33 no.4
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• pp.77-85
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• 2018

Objective : This study was intended to examine the effects of water extract of Prunellae Spica (PS), which is a herb with 'cold' nature based on hot and cold theory of traditional Korean medicine. Methods : Hyperthyroidism was induced in SD rats by LT4 (0.5 mg/kg, i.p.) daily for four weeks. After 2 weeks of LT4 injection, rats were divided randomly into four groups; normal, LT4-induced hyperthyroid control, PS extract (500 mg/kg, p.o.)-treated group, and propylthiouracil (PTU, 10 mg/kg, s.c.)-treated positive group. After 2 weeks of drug treatment, all rats were sacrificed and harvested blood samples and thyroid tissues. The changes of body weight, food and water intake, and body temperature were measured weekly. Serological markers were analyzed in sera using an enzyme-based assay, and thyroid tissues were stained with Hematoxylin & Eosin (H&E). Brain and dorsal root ganglion (DRG) tissues were isolated and analyzed the expression of transient receptor potential (TRP) channels by Western blot. Results : PS extract administration attenuated the loss of body weight and the increase of body temperature in LT4-induced hyperthyroidism rats. PS extract increased the level of thyroid stimulating hormone (TSH) and decreased tiiodothyronine (T3) and tetraiodothyronine (T4). In action mechanism, PS extract regulated the expression of transient receptor potential channel subfamily V member 1 (TRPV1) and transient Receptor Potential channel subfamily M member 8 (TRPM8), the thermoregulators. Conclusion : To conclude, PS extract can improve the symptoms of hyperthyroidism through regulation of the thyroid hormones imbalance and thermoregulation via TRP channels.

• Microbiology and Biotechnology Letters
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• v.37 no.2
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• pp.170-175
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• 2009

The extract of Platycarya strobilacea is known to possess a wide range of pharmacological activities including anti-inflammatory, anti-fungal, and anti-cancer properties. We have reported that the ethyl acetate fraction of Platycarya strobilacea (PS-ET fraction) has high potential as an antioxidant agent (J. Soc. Cosmet. Scientists Korea 34(4) 275, 2008). In this study, antibacterial activity of the fraction and stability of the cream containing 0.2% PS-ET fraction were investigated for the application to cosmetics. Antibacterial activity of PS-ET fraction against various skin pathogenic bacteria (Propionibacterium acnes, Staphylococcus aureus, and Pityrosporum ovale) was measured by minimum inhibitory concentration (MIC). MIC values of PS-ET fraction on P. acnes, S. aureus, and P. ovale were 0.13%, 0.06% and 0.25%, respectively. The results showed that the antibacterial activity of the fraction was the highest in the S. aureus. For the stability evaluation, pH and viscosity of the cream containing 0.2% PS-ET fraction were measured. The results showed that pH changes of the cream containing PS-ET fraction was lower than the control cream without PS-ET fraction. And the PS-ET fraction could repress the decrease of viscosity of the cream against sunlight treatment. These results suggest that the fraction of Platycarya strobilacea has high potential as bactericide against the skin pathogenic bacteria and could be added to improve the stability of cosmetic products.

• Journal of Ginseng Research
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• v.22 no.4
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• pp.267-273
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• 1998

Pretreatment of acidic polysaccharide of Korean red ginseng (AcPS) for two weeks remarkably lowered the elevated content of lipid peroxide and levels of aminotransferases, sorbitol dehydrogenase, ${\gamma}$-glutamyltransferase, alkaline phosphatase and lactate dehydrogenase in liver intoxicated by acetaminophen (AA) . Pretreatments of AcPS also strengthen the liver function of glutathione related detoxication system indicated by glutathione contents and activities of glutathione S-transferase and glutathione reeducates which were affected by AA treatments. Activity of ${\gamma}$-glutamylcysteine syntheses was not changed by AcPS pretreatment whereas the activity of flu tathione reeducates was increased significantly. These results collectively indicate that the treatments of AcPS can promote the metabolism of lipid and reduce the production of peroxide in acetaminophen-intoxicated animals.

• Journal of Chest Surgery
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• v.19 no.2
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• pp.238-242
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• 1986

The prognosis of patients with VSD and pulmonary hypertension is at least partially related to the reversibility of pulmonary hypertension after surgery. To predict postoperative pulmonary arterial pressure, immediate postbypass values were compared with preoperative hemodynamic data in 18 surgically closed VSD patients aged 6 to 80 months. The following results were obtained. 2] There was a good correlation between preoperative PP/PS and postoperative PP/PS in patients aged over 24 months [r=0.685, p<0.05], and in patients whose QP/QS were over 2.0 [r=0.686, p<0.01]. 3] There was also a good correlation between pump time and postoperative PP in total patients [r=0.697, p<0.005]. 4] Direct correlations were found between preoperative PP/PS and immediate postbypass PP/PS in patients aged over 24 months and in patients whose QP/QS>2.0, but the effect of CPB would participate in some degree. So it may be necessary to reevaluate their relationship after the effect of CPB have been disappeared.

• The Korean Journal of Ceramics
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• v.4 no.1
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• pp.28-32
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• 1998

This paper reports on photoluminescence (PL), luminescence decay curves, and compositional analysis of porous silicon(PS) which is aged under air ambient by Fourier transform infrared vibrational spectroscopy (FTIR) and by Auger electron spectroscopy (AES). Porous silicos which has been aged under air ambient yields two PL band structures, i.e. blue/violet PL and red PL. The evolution of a blue/violet band is pronounced, especially for thin PS film which is prepared in dilute HF solution. The blue/violet PL band has been observed initially to increrase rapidly with aging, then saturated with further atmospheric aging. The ambient air aged PS exhibits a fast decay time of sub-nanosecond at room temperature and shows appreciably faster decay time than that at 20K. Atmospheric aging of this thin blue/violet luminescing PS yield non-stoichiometric oxide judging from the vibrational spectra of Si-O and AES analysis.

• Progress in Superconductivity
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• v.9 no.2
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• pp.157-161
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• 2008

Due to high speed operations and ultra low power consumptions RSFQ logic circuit is a very good candidate for future electronic device. The focus of the RSFQ circuit development has been on the advancement of analog-to-digital converters and microprocessors. Recent works on RSFQ ALU development showed the successful operation of an 1-bit block of ALU at 40 GHz. Recently, the study of an RSFQ analog-to-digital converter has been extended to the development of a single chip RF digital receiver. Compared to the voltage logic circuits, RSFQ circuits operate based on the pulse logic. This naturally leads the circuit structure of RSFQ circuit to be pipelined. Delay time on each pipelined stage determines the ultimate operating speed of the circuit. In simulations, a two junction Josephson transmission line's delay time was about 10 ps, a splitter's 14.5 ps, a switch's 13 ps, a half adder's 67 ps. Optimization of the 4-bit ALU circuit has been made with delay time consideration to operate comfortably at 10 GHz or above.