• ALGAE
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• v.36 no.3
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• pp.175-193
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• 2021

This study provides the first report of the presence of Coolia malayensis in the Mediterranean Sea, co-occurring with C. monotis. Isolated strains from the Gulf of Gabès, Tunisia (South-eastern Mediterranean) were identified by morphological characterization and phylogenetic analysis. Examination by light and scanning electron microscopy revealed no significant morphological differences between the Tunisian isolates and other geographically distant strains of C. monotis and C. malayensis. Phylogenetic trees based on ITS1-5.8S-ITS2 and D1-D3/28S rDNA sequences showed that C. monotis strains clustered with others from the Mediterranean and Atlantic whereas the C. malayensis isolate branched with isolates from the Pacific and the Atlantic, therefore revealing no geographical trend among C. monotis and C. malayensis populations. Ultrastructural analyses by transmission electron microscopy revealed the presence of numerous vesicles containing spirally coiled fibers in both C. malayensis and C. monotis cells, which we speculate to be involved in mucus production.

• Nano
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• v.13 no.11
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• pp.1850136.1-1850136.12
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• 2018

Three-dimensional (3D) mixed phases NiSe nanoparticles growing on the nickel foam were synthesized via a simple one-step hydrothermal method. A series of experiments were carried out to control the morphology by adjusting the amount of selenium in the synthetic reaction. Meanwhile, the as-prepared novel column-acicular structure NiSe exist three advantages including ideal electrical conductivity, high specific capacity and high cycling stability. It delivered a high capacitance of $10.8F\;cm^{-2}$ at a current density- of $5mA\;cm^{-2}$. An electrochemical capacitor device operating at 1.6 V was then constructed using NiSe/NF and activated carbon (AC) as positive and negative electrodes. Moreover, the device showed high energy density of $31W\;h\;kg^{-1}$ at a power density of $0.81kW\;kg^{-1}$, as well as good cycling stability (77% retention after 1500 cycles).

• Natural Product Sciences
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• v.27 no.4
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• pp.234-239
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• 2021

Masclura tricuspidata, also called as Cudrania tricuspidata, is one of the most common Moraceae family plants in East Asia. Its trivial name follows mulberry due to the similar morphology. Investigation of the bioactive constituents of M. tricuspidata leaves yielded a new xanthone derivative along with twenty known compounds through various chromatographic techniques. A new compound was defined as mascluraxanthone (3), a prenylated xanthone glucoside on the basis of 1D and 2D NMR and MS data. Twenty known compounds were identified as four xanthone derivatives (1-2 and 4-5), two flavans (6-7), six flavanol derivatives (8-13), a flavonone (14) and seven flavonol derivatives (15-21). Among the isolated compounds, flavanol and flavonoid derivatives with 3',4'-OH groups showed antioxidant and anti-tyrosinase activities. Conclusively, the leaves of M. tricuspidata are rich in aromatic compounds including xanthones and flavonoids. In addition, these constituents showed antioxidant and anti-tyrosinase potentials, which might be useful for oxidative stress related diseases.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.35 no.4
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• pp.359-365
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• 2022

The development of efficient electron donor (or hole-transporting) molecules that can be used in various optoelectronic device fields is highly demanded. In this work, a novel class of triptycene-based three-dimensional (3D) triphenylamine (TI-TPA) derivatives with different end substituents was designed and prepared for transparent electron donor materials. Owing to the rigid 3D triptycene framework, the obtained TI-TPA derivatives had an amorphous morphology with high thermal decomposition temperature. The oxidation potential of these TI-TPA derivatives decreased as the electron donating strength of the end substituent increased. Among TI-TPA derivatives, TI-TPA-OMe exhibited the highest HOMO level (-5.31 eV) which is similar to that of Spiro-OMeTAD (-5.22 eV). In addition, TI-TPA-OMe was found to form a strong charge transfer complex with the triptycene-based acceptor TI-BQ, leading to a new absorption band at around 640 nm. These results can be applied for developing efficient electron donor materials that can mimic the advantages of the spiro-linked structure and TPA units of Spiro-OMeTAD.

• Journal of Electrochemical Science and Technology
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• v.7 no.3
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• pp.190-198
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• 2016

Application of fuel cell to produce renewable energy for commercial purpose is limited by the high cost of Pt based electrode materials. Development of inexpensive, high energetic electrode is the need of the hour to produce pollution free energy using bio-fuel through a fuel cell. Ni-Cu and Ni-CeO₂-Cu electrode materials, electro synthesized by pulse current have been developed. The surface morphology of the electrode materials is controlled by different deposition parameters in order to produce a high current from the electro-oxidation of the fuel, the ethanol. The developed materials are electrochemically characterized by Cyclic Voltammetry (CV), Chronoamperometry (CA) and Potentiodynamic polarization tests. The results confirm that the high current is due to their enhanced catalytic properties viz. high exchange current density (i₀), low polarization resistance (R_p) and low impedance. It is worthwhile to mention here that the addition of CeO₂ to Ni-Cu has outperformed Pt as far as the high electro catalytic properties are concerned; the exchange current density is about eight times higher than the same on Pt surface. The morphology of the electrode surface examined by SEM and FESEM exhibits that the grains are narrow and sub spherical with 3D surface, containing vacancies in between the elongated grains. The fact has enhanced more surface area for electro oxidation of the fuel, giving rise to an increase in current. Presence of Ni, CeO₂, and Cu is confirmed by the XRD and EDXS. Fuel cell fabricated with Ni-CeO₂-Cu material electrode is expected to produce clean electrical energy at cheaper rates than conventional one, using bio fuel the derived from biomass.

• The Korean Journal of Zoology
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• v.6 no.2
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• pp.21-27
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• 1963

This study is concerned with alterations in chromosomes (numbers and morphology) when the culture of Chinese hamster cells (FAF-28 strain) was treated by steroids, testosterone and DOC. 1. In 200 cells of normal untreated cells as control population the chromosome of stemline was decided as which was contained in 158 cells ; that is , in 79 percent of the population. The average chromosome number in above 20 cells observed was calculated as 23.95 with minimum limit at 20 and maximum limit at 70. 2. Many different chromosome numbers, ranging from 19 to 352 were observed in the 200 cells treated by testosterone. The diploid number of 22 showed the peak of variation curve was counted in 71 cells (35.5%) and an average chromosome number of stemline was 22 which was counted in 74 cells (37%). While all of the chromosome number of stemline was 22 which was counted in 74 cells (37%). While all of the chromosome numbers in the 200 cells observed ranged from 20 to 181 , an average chromosome number was also found to be 30.09. 4. The chromosome component in the cultured normal FAF-28 cells with 22 diploid chromosomeswas as follows ; 9a) 2 paris were long and metacentric (LM), (b) 3 pairs were medium length and metacentric (MM), (c) 3 pairs were small and subtelocentric (SS) and (d) 3 pairs were small and metacentric (SM). 5. The twenty cells with 44 chromosomes were selected at random from each cell population treated with testosterone and DOC , so that chromosome idiogram and morphology could be studies. In the twenty cells of the testosterone treated population the average ratio of above four groups, LM ; MM;Ss:SM, was found to be 8.6 : 10.8:13.5:10.7. On the other hand, the average ratio in the same number of cells of the DOC treated one was 7.7 :11.4:12.5:12.7. 6. The five types of the altered chromosomes morphologically in the hundred cells selected at random from each cell population treated by testosterone and DOC were observed (Type I-V). The thirty-one altered chromosomes were found to be in the testosterone treated cell population and the sixteen in DOC treated.

• Reproductive and Developmental Biology
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• v.28 no.1
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• pp.7-12
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• 2004

This study was performed to establish the effective culture condition for the establishment of clonal lines from porcine fetal fibroblast cells. Fibroblasts derived from a pig fetus (Day 50) were cultured and passaged two times before use. A single cell was seeded in 96-well plates, cultured in medium supplemented with different concentrations of FBS, catalase or $\beta$-mercaptoethanol ($\beta$ME), and classified by cell size and morphology. Cells were passaged two times into 4-well dish before freezing. The establishment efficiencies were not different among different concentrations of FBS (0.3 to 5.1%). However, population doubling time (PDT) was significantly decreased by increasing the FBS concentration (P＜0.05). The establishment efficiency of $\beta$ME-added group (10.4%) was significantly higher than those of catalase-added and control groups (3.5%, and 3.5%, respectively, p＜0.05), and PDT was significantly decreased (23.6 vs 28.1, and 25.5 h, respectively, p＜0.05). However, catalase did not show a positive effect on the establishment efficiency. Cell size and morphology did not affect the establishment efficiency and PDT of clonal lines. The result of present study shows that the establishment efficiency of clonal cell lines can be enhanced by the culture in media supplemented with 30% FBS and $\beta$ME.

• The Korean Journal of Physiology and Pharmacology
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• v.16 no.6
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• pp.423-429
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• 2012

Brain ischemia leads to overstimulation of N-methyl-D-aspartate (NMDA) receptors, referred as excitotoxicity, which mediates neuronal cell death. However, less attention has been paid to changes in synaptic activity and morphology that could have an important impact on cell function and survival following ischemic insult. In this study, we investigated the effects of reperfusion after oxygen/glucose deprivation (OGD) not only upon neuronal cell death, but also on ultrastructural and biochemical characteristics of postsynaptic density (PSD) protein, in the stratum lucidum of the CA3 area in organotypic hippocampal slice cultures. After OGD/reperfusion, neurons were found to be damaged; the organelles such as mitochondria, endoplasmic reticulum, dendrites, and synaptic terminals were swollen; and the PSD became thicker and irregular. Ethanolic phosphotungstic acid staining showed that the density of PSD was significantly decreased, and the thickness and length of the PSD were significantly increased in the OGD/reperfusion group compared to the control. The levels of PSD proteins, including PSD-95, NMDA receptor 1, NMDA receptor 2B, and calcium/calmodulin-dependent protein kinase II, were significantly decreased following OGD/reperfusion. These results suggest that OGD/reperfusion induces significant modifications to PSDs in the CA3 area of organotypic hippocampal slice cultures, both morphologically and biochemically, and this may contribute to neuronal cell death and synaptic dysfunction after OGD/reperfusion.

• Journal of Plant Biology
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• v.36 no.4
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• pp.399-406
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• 1993

유채(Brassica napus L. cv. Topas) 소포자 배양에 의한 기내 배발생 과정을 관찰하고 발생과정에 따른 총단백질의 변화 양상을 이차원 전기영동을 통하여 분석하였다. 배양에 적합한 소포자의 발달 단계는 4,6-diamidino-2-phenylindole (DAPI) 형광염색으로 핵상관찰을 통하여 결정하였다. 최초의 소포자 생존율은 63.9%였으며 이러한 생존율의 차이로 배양초기에 소포자의 이형성이 나타났다. 배 발달 경로에 따른 최초의 세포분열은 화분벽 안에서 균등분열로 시작되어 배병의 발달이 선행된 후 배 발생이 일어났으며, 구형, 심장형, 어뢰형으로의 배 발달은 여러 조직의 분화와 더불어 빠르게 진행되었다. 소포자배 발달과정을 치상단계의 소포자, 배양 3일째의 초기 분열세포, 구형 및 심장형배, 어뢰형배, 성숙한 자엽단계의 배 등의 5단계로 나누어 각각 2차원 전기영동을 수행한 결과, 최초 소포자 단계에서 나타났던 23개의 단백질들은 배 달달 경로로 진행됨에 따라 사라지고, 배양 3일째에는 8개의 단백질이 특이적 또는 지속적으로 발현되었다. 배의 발달과 더불어 20∼50 kD 사이에서 총 42개의 단백질이 급격히 나타나거나 또는 후기 배로 진행하면서 점차적으로 발현되었다.

• BMB Reports
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• v.36 no.3
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• pp.269-274
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• 2003

In the fight against cancer, novel chemotherapeutic agents are constantly being sought to complement existing drugs. Various studies have presented evidence that the apoptosis that is induced by these anticancer agents is implicated in tumor regression, and Bcl-2 family genes play a part in apoptosis following treatment with various stimuli. Here, we present data that a styrylpyrone derivative (SPD) that is extracted from the plant Goniothalamus sp. showed cytotoxic effects on the human breast cancer cell line MCF-7. SPD significantly increased apoptosis in MCF-7 cells, as visualized by phase contrast microscopy and evaluated by the Tdt-mediated dUTP nick end-labeling assay and nuclear morphology. Western blotting and immunostaining revealed up-regulation of the proapoptotic Bax protein expression. SPD, however, did not affect the expression of the anti-apoptotic protein, Bcl-2. These results, therefore, suggest SPD as a potent cytotoxic agent on MCF-7 cells by inducing apoptosis through the modulation of Bax levels.