• Bulletin of the Korean Chemical Society
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• v.24 no.6
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• pp.739-743
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• 2003

New quaternary compounds $ANb_2PS_{10}$ (A = Na, Ag) and $AuNb_4P_2S_{20}$ were synthesized and characterized. The structures of three compounds consist of one-dimensional infinite chains built by [$Nb_2S_{12}$] and [$PS_4$] units. Cation atoms are occupied within the van der Waals gap of sulfur atoms between infinite chains to make -S…$M^+$…S- contacts. There is only one Au atom site and so crystallographically a unit cell contains four equivalent Au atoms in $AuNb_4P_2S_{20}$. This is only the half of the numbers of Na or Ag atoms in $NaNb_2PS_{10}$ or $AgNb_2PS_{10}$. The ratio between $Nb_2PS_{10}$ matrix vs the cation is, therefore, 1 : 1 for Ag and Na, but it is 2 : 1 for Au. Mixed valency in Au or Nb was expected to balance the charge in the latter compound. The electronic structures calculated based on the extended Huckel tight-binding method show that $ANb_2PS_{10}$ (A = Ag, Na) are semiconducting, while $AuNb_4P_2S_{20}$ is metallic, which is not consistent with the experimental results of these three compounds that all exhibit semiconducting property. The result of calculation suggests that $AuNb_4P_2S_{20}$ might be a magnetic insulator. Magnetic measurement experiment exactly proved that the compound is a Slater antiferromagnetic material with the Neels' temperature of 45 K. It is recognized, therefore, that electronic structure analysis is very useful to understand the properties of compounds.

• Culinary science and hospitality research
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• v.18 no.1
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• pp.65-76
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• 2012

As pumpkin is gaining popularity as health functional food among people, this study purposed to prepare powder pumpkin soup of instant food style using ordinary pumpkin (Cucurbita moschata Duch.) that is an oriental pumpkin variety, and sweet pumpkin (Cucurbita maxima Duch.) that is a western pumpkin variety, and to examine its mechanical and sensory characteristics. The viscosity of powder pumpkin soup was higher when the addition ratio of ordinary pumpkin powder was higher than that of sweet pumpkin powder. On the contrary, sugar contents was higher when the addition ratio of sweet pumpkin powder was high. Color did not show any consistent tendency by the addition ratios of ordinary pumpkin powder and sweet pumpkin powder, and lightness was highest in PS2, redness in PS3, and yellowness in PS1. In the results of sensory evaluation through quantitative descriptive analysis, color, glossiness, and the intensity of pumpkin smell were highest in PS3, the intensity of sweetness in PS1, the intensity of saltiness in PS4. In the results of sensory evaluation through palatability test, PS3 showed the highest palatability in terms of appearance, flavor, color, taste, concentration, mouth feel, and overall palatability. Summing up these results, when powder pumpkin soup was prepared at different mixture ratios of ordinary pumpkin powder and sweet pumpkin powder, PS3 showed the most superior mechanical and sensory characteristics. Thus, it is considered most adequate to prepare powder pumpkin soup at the mixture ratio of ordinary pumpkin powder 75% and sweet pumpkin powder 25%.

• Journal of the Institute of Electronics and Information Engineers
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• v.51 no.9
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• pp.182-189
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• 2014

A tapped delay line time-to-digital converter (TDC) can be easily implemented using internal carry chains in a field-programmable gate array, and hence, its use is widespread. However, the tapped delay line TDC suffers from performance degradation because of differences in the delay times of dedicated carry chains. In this paper, a dual edge measurement method is proposed instead of a typical step signal to the delay cell to compensate for the performance degradation caused by wide-delay cells in carry chains. By applying a pulse of a fixed width as an input to the carry chains and using the time information between the up and down edges of the signal pulse, the timing accuracy can be increased. Two dedicated carry chain sites are required for the dual edge measurements. By adopting the proposed dual edge measurement method, the average delay widths of the two carry chains were improved by more than 35%, from 17.3 ps and 16.7 ps to 11.2 ps and 10.1 ps, respectively. In addition, the maximum delay times were improved from 41.4 ps and 42.1 ps to 20.1 ps and 20.8 ps, respectively.

• Journal of Microbiology and Biotechnology
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• v.19 no.11
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• pp.1482-1489
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• 2009

In this study, we investigated the anti-proliferative effect of polysaccharides from Salicornia herbacea on HT-29 human colon cancer cells. Crude polysaccharides from S. herbacea (CS) were prepared by extraction with hot steam water, and fine polysaccharides from S. herbacea (PS) were obtained through further size exclusion chromatography. The anti-proliferative effect of CS and PS were measured using the MTS assay, apoptosis analysis, cell cycle analysis, and RT-PCR. HT-29 cells were treated with CS or PS at different dosages (0.5, 1, 2, 4 mg $ml^{-1}$) for 24 or 48 h. CS and PS inhibited proliferation and stimulated apoptosis of cells in a dose-dependent manner. Flow cytometric analysis after Annexin V-FITC and PI staining revealed that treatment with CS or PS increased total apoptotic death of cells to 24.99% or 91.59%, respectively, in comparison with the control (13.51 %). PS increased early apoptotic death substantially - up to 12 times more than the control. Treatment with CS or PS resulted in a concentration-dependent increase of the G2/M cell population of the cell cycle as determined by flow cytometry. G2/M arrest was induced significantly with the highest concentration (4 mg $ml^{-1}$) of PS. RT-PCR was performed to study the correlation between G2/M arrest and transcription of cell cycle control genes. The anti-proliferative activity of CS and PS was accompanied by inhibition of cyclin B1, and Cdc 2 mRNA. Moreover, both CS and PS induced expression of the p53 tumor suppressor gene and the Cdk inhibitor p21. These results suggest that polysaccharides from S. herbacea have anti-cancer activity in human colon cancer cells.

• Journal of Nutrition and Health
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• v.57 no.2
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• pp.261-274
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• 2024

Purpose: Recently, high-protein diets have become highly popular, and the market for protein products has steadily increased in Korea together with the development of various types of such products. However, there is limited information on the consumption of protein supplements (PS) or protein-fortified foods (PF). Thus, this study aimed to evaluate the use of PS/PF among young adults in Jeju. Methods: A total of 350 adults (140 men and 210 women) aged 19-39 years voluntarily participated in this study from June 2022 to May 2023. PS/PF use was measured using a questionnaire. Dietary intake was assessed using a 24-hour dietary recall. Results: Approximately 31.4% of the participants (n = 110) had consumed PS/PF for more than 2 weeks during the past year and 71.8% of them (n = 79) were still consuming these products (PS/PF consumers). The PS/PF consumers tended to be male and physically active (p < 0.05 for all). The most frequent reason for PS/PF use was muscle gain (59.5%), followed by protein supplementation (19.0%) and body fat loss (13.9%), and the most frequent type of PS/PF consumed was powders (70.6%), followed by drinks (17.7%) and bars (8.8%). The PS/PF consumers tended to consume a high-protein low-carbohydrate diet compared to the non-consumers. The prevalence of consuming dietary protein less than the estimated average requirement (EAR) was significantly lower in PS/PF consumers (13.9%) compared to non-consumers (25.4%; p = 0.0316). Conclusion: These findings indicate that the necessity of protein supplementation should be determined based on the current dietary protein intake and individual requirements. The study also provides the basic information for establishing guidelines for appropriate protein intake.

• Biomolecules & Therapeutics
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• v.5 no.2
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• pp.194-201
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• 1997

The hepatoprotective activity of six extracts (BE, EE, HH, PS-1, PS-2, KP) from Artimisia iwayomogi was investigated against experimentally produced hepatic damages. Silymarin, DDB and UDCA were used as reference compounds. Treatment with PS-1 extract reduced hepatic demages induced by $CCl_4$, acetaminophen and ANIT but it did not alter ethionine-induced hepatotoxicity In addition, PS-1 extract showed a protective effect against chronic $CCl_4$-induced hepatotoxicity as well as liver regeneration. PS-2 and KP extracts exhibited significant antihepatotoxic effects on D-galactosamine-induced hepatitis. Treatment with EE extract inhibited ethionine-induced fatty liver. These data indicate that the PS-1 extract is the roost hepato-protective constituent and rationalize the traditional use of this plant in hepatobiliary disorders.

• The Korean Journal of Rheology
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• v.9 no.3
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• pp.89-96
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• 1997

PS/PPO 블렌등의 동적 탄성율 E*($\omega$)와 동적 스트레인-광학계수 O*($\omega$)을 유리전이 영역에서 동시에 측정하여, PS/PPO 3종류조성블렌드의 E*($\omega$)와 O*($\omega$)완화거동을 조성 단 일 중합체와 비교고찰하였다. PS/PPO 블렌드의 $\alpha$-분산 점탄성 거동은 조성에 관계없이 거 의 유사하여 조성 고분자가 상호 협동적으로 완화하는 것을 알수 있었다. 그러나 광학적 완 화 스펙트럼 O*($\omega$)는 정성적으로 명확히 다른 거동을 보였다. 단일 PS와 PPO의 O*($\omega$)는 전 영역에 걸쳐 상반된 부로를 나타냈으며 두 고분자의 블렌드는 조성고분자의 반대부호를 상호보상으로 인하여 복굴절이 감소하였다. 3종류블렌드는 PPO의 조성이 증가함에 따라 상 호보상에 의해 O*($\omega$)의부호가 순차적으로 변하여 반전하였으며, 저 복굴절 PS/PPO 블렌드 의 PS조성이 65-80wt% 범위내에 있음을 추정할수 있었다. 상이한 부호를 갖는 복굴절 특 성으로 인하여 블렌드 내에서 각 성분 고분자의 완화 기여를 다순 가성법칙에 의해 정량적 으로 계산하는 것이 가능하였다. 또한 PS/PPO 블렌드의 상용성을 광학적 부분 기여 파라메 터를 사용하여 고찰하였다.

• Journal of Powder Materials
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• v.23 no.4
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• pp.276-281
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• 2016

Carbonyl iron (CI) is successfully incorporated as an additive into a polystyrene (PS) matrix via a highenergy ball milling method, under an n-hexane medium with volume fractions between 1% and 5% for electromagnetic interference shielding applications by the combination of magnetic CI and an insulating PS matrix. The morphology and the dispersion of CI are investigated by field emission scanning electron microscopy, which indicates a uniform distribution of CI in the PS matrix after 2 h of milling. The thermal behavior results indicate no significant degradation of the PS when there is a slight increase in the onset temperature with the addition of CI powder, when compared to the as-received PS pellet. After milling, there are no interactions between the CI and the PS matrix, as confirmed by Fourier transformed infrared spectroscopy. In this study, the milled CI-PS powder is extruded to make filaments, and can have potential applications in the 3-D printing industry.

• Journal of Soil and Groundwater Environment
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• v.26 no.1
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• pp.45-53
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• 2021

The removal of 2,4-dichlorophenoxyacetic acid (2,4-D) in aqueous solution by coupled electro-oxidation and Fe(II) activated persulfate oxidation process was investigated. The electrochemical oxidation was performed using carbon sheet electrode and persulfate using Fe(II) ion as an activator. The oxidation efficiency was investigated by varying current density (2 - 10 mA/㎠), electrolyte (Na2SO4) concentration (10 - 100 mM), persulfate concentration (5 - 20 mM), and Fe(II) concentration (10 - 20 mM). The 2,4-D removal efficiency was in the order of Fe(II) activated persulfate-assisted electrochemical oxidation (Fe(II)/PS/ECO, 91%) > persulfate-electrochemical oxidation (PS/ECO, 51%) > electro-oxidation (EO, 36%). The persulfate can be activated by electron transfer in PS/ECO system, however, the addition of Fe(II) as an activator enhanced 2,4-D degradation in the Fe(II)/PS/ECO system. The 2,4-D removal efficiency was not affected by the initial pHs (3 - 9). The presence of anions (Cl- and HCO3-) inhibited the 2,4-D removal in Fe(II)/PS/ECO system due to scavenging of sulfate radical. Scavenger experiment using tert-butyl alcohol (TBA) and methanol (MeOH) confirmed that although both sulfate (SO4•-) and hydroxyl (•OH) radicals existed in Fe(II)/PS/ECO system, hydroxyl radical (SO4•-) was the predominant radical.

• Journal of Environmental Science International
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• v.6 no.4
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• pp.369-378
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• 1997

The effects of various intensity of W-B on barley seeding were investigated by PS I and II activities and chlorophyll fluorescence. The Inhibitory effect of UV-B radiation on electron transport activity was Increased as the intensity of UV-B Irradiation was increased. Especially, PS I is more sensitive to UV-B radiation than PS I is. By the addition of uncle electron donor, DPC, to the chloroplasts of the barley seedlings treated with UV-B, the photoreduction of DCPIP was recovered by only 1 IBI on electron transport activity. However, the activity of PS II was Inhibited by 45% by the treatment with UV-B, but recovered it only 11% by the addition of DPC. These suggest that other sites besides the oxidation site of PS II may be affected more by UV-B Irradiation. As the intensify of UV-B was Increased, Fo was Increased while Fv was decreased, and thus Fv/Fm was decreased. This means that photochemical efficiency was reduced. With this parameters, it might be that UV-B radiation affected adversely to around PS II.