• BMB Reports
• /
• v.50 no.1
• /
• pp.5-11
• /
• 2017

One of the characteristics of the neurons that distinguishes them from other cells is their complex and polarized structure consisting of dendrites, cell body, and axon. The complexity and diversity of dendrites are particularly well recognized, and accumulating evidences suggest that the alterations in the dendrite structure are associated with many neurodegenerative diseases. Given the importance of the proper dendritic structures for neuronal functions, the dendrite pathology appears to have crucial contribution to the pathogenesis of neurodegenerative diseases. Nonetheless, the cellular and molecular basis of dendritic changes in the neurodegenerative diseases remains largely elusive. Previous studies in normal condition have revealed that several cellular components, such as local cytoskeletal structures and organelles located locally in dendrites, play crucial roles in dendrite growth. By reviewing what has been unveiled to date regarding dendrite growth in terms of these local cellular components, we aim to provide an insight to categorize the potential cellular basis that can be applied to the dendrite pathology manifested in many neurodegenerative diseases.

• Macromolecular Research
• /
• v.14 no.6
• /
• pp.630-633
• /
• 2006

In heterojunction photovoltaic devices of $ITO/TiO_2/poly$(3-alkylthiophene)/Au, the photo current was characterized at different temperatures for different alkyl chain lengths and regioregularities: regiorandom, regioregular poly(3-hexylthiophene), and regioregular poly(3-dodecylthiophene). The regioregularity and alkyl chain length affected the photovoltaic characteristics due to differences in hole-carrier transportation. The drift charge mobilities of these devices were analyzed by the space-charge-limited current theory using the relation between the dark current and the bias voltage. The photocurrent in the devices based on poly(3-alkylthiophene)s decreased rapidly below the temperature at which the drift charge mobility was $10^{-5}\;cm^2/V{\cdot}s$.

• 한국정보디스플레이학회:학술대회논문집
• /
• 2002.08a
• /
• pp.819-821
• /
• 2002

Photoluminescenc (PL) and low-voltage cathodoluminescence (CL) characteristics of $[xSrTiO_3+(1-x)Li_2TiO_3]:Pr^{3+}$ and $[xSrTiO_3+(1-x)Na_2TiO_3]:Pr^{3+}$ systems were investigated. The red luminescence intensities of these compounds are enhanced remarkably by the incorporation of $Li^+$ or $Na^+$ ion as compared to that of $SrTiO_3:Pr^{3+}$. The enhanced luminescence is speculated to result from both the charge compensation of $Pr^{3+}$ site and oxygen vacancies generated in the lattices by $Li^+$ or $Na^+$ ion.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.45 no.5
• /
• pp.507-512
• /
• 2012

One leptocephalus (TL 59.9 mm) from the family Ophichthidae collected from Jeju Island, Korea, was identified using morphological and molecular methods. Our ophichthid leptocephalus was identified as belonging to the genus Muraenichthys based on morphological characters: 157 myomeres; the origin of the dorsal fin located a little in front of the anus; a distinct melanophore present on the opercle; and six gut swellings present. An analysis of 886 base pairs of the 12S rRNA mtDNA sequences showed that our leptocephalus must be Muraenichthys gymnopterus, because its sequences were concordant with those of an adult M. gymnopterus (d=0.001) and next to those of Muraenichthys sp. leptocephalus (d=0.034). Here, we are the first to describe the morphological characteristics of the M. gymnopterus leptocephalus.

• Journal of Microbiology and Biotechnology
• /
• v.23 no.12
• /
• pp.1645-1653
• /
• 2013

Archaea are prokaryotic organisms distinct from bacteria in the structural and molecular biological sense, and these microorganisms are known to thrive mostly at extreme environments. In particular, most studies on halophilic archaea have been focused on environmental and ecological researches. However, new species of halophilic archaea are being isolated and identified from high salt-fermented foods consumed by humans, and it has been found that various types of halophilic archaea exist in food products by culture-independent molecular biological methods. In addition, even if the numbers are not quite high, DNAs of various halophilic archaea are being detected in human intestines and much interest is given to their possible roles. This review aims to summarize the types and characteristics of halophilic archaea reported to be present in foods and human intestines and to discuss their application as well.

• Tribology and Lubricants
• /
• v.25 no.4
• /
• pp.236-242
• /
• 2009

Oil viscosity is one of the important parameters for machinery condition monitoring. Basically, it is expressed as kinematic viscosity measured by capillary flow and dynamic or absolute viscosity measured by rotary shear viscometry. Recently, acoustic wave techniques appear in the market, measuring viscosity as the product of dynamic viscosity and density. For Newtonian fluids, knowledge of density allows conversion from one viscosity parameter to the other at a specific shear rate and temperature. In this work, oil samples with different chain lengths of viscosity index (VI) improvers and concentrations were examined by different viscometric techniques. Results showed that acoustic viscosity measurements give misleading results for oil samples with high molecular weight VI improvers and at low temperatures ${\leq}40^{\circ}C$.

• Applied Microscopy
• /
• v.25 no.1
• /
• pp.15-29
• /
• 1995

Legumin was purified from the endosperm cells of the ginseng seed and analyzed its characteristics. Distributional patterns of the legumin in the endosperm cells were identified using the immunocytochemical method. Legumin was glycoprotein composed of two subunits, molecular weights about 33,000 and 25,000 respectively. The molecular shape of purified legumin stained negatively seems to have hexagonal structure about 10 nm in size. It was localized at the rER, dictyosomes, and in the vacuoles at the early developing stage. Legumin was glycosylated in the dictyosomes and transported from the dictyosomes to the vacuoles. Legumin was accumulated into the central vacuole via the dictyosomes while the endosperm cells were developing. The armorphous proteins containing legumin were scattered randomly within the central vacuoles, which were aggregated together and became gradually spherical shape. Legumin was distributed within the globular protein bodies in the endosperm cells of matured seed. However legumin was not found in the globoids located in the protein bodies.

• Proceedings of the KAIS Fall Conference
• /
• 2010.05b
• /
• pp.961-964
• /
• 2010

A semi-empirical fluctuation term is presented to improve a classical equation of state (EOS) for volumetric properties in the critical region. The term is based on the two assumptions: (1) The Helmholtz energy is individually divided into classical and long-range density fluctuation contribution (2) All molecules form cluster near the critical region due to long-range density fluctuation. To formulate such molecular cluster, we extended the Veytsman statistics originally developed for the cluster due to hydrogen bonding. The probability function in the statistics is modified to represent the characteristics of long-range density fluctuation vanishing far from critical region. The proposed fluctuation contribution was incorporated into the Sanchez-Lacombe EOS and the combined model with 6 adjustable parameters has been tested against experimental VLE data. The combined model is found to well represent flatten critical isotherm for methane and top of the coexistence curve for the tested components. The prediction results for caloric data are in good agreement with the experimental data.

• Applied Chemistry for Engineering
• /
• v.1 no.1
• /
• pp.1-10
• /
• 1990

Polysilane derivatives are attracting considerable attention as a new class of material since 1980. The preparation methods of low molecular weight, cyclic, and high molecular weight polysilane derivatives are described, and also photochemistry characteristics for silicon-silicon single bond and for the nature of the substituent on silicon backbone are discussed. Polysilanes may be used as a precursors to silicon carbide fiber, as photoresist in microelectronics, as photoconductor, and as photoinitatior for free radical polymerization.

• Proceedings of the KIEE Conference
• /
• 2000.11c
• /
• pp.443-445
• /
• 2000

The high mobilitie sallow larger current to be reached under operation in the space charge limited conduction region, hence facilitate access to higher luminance as required for passive matrix panel. In this work, we have investigated the molecular alignment control effect of organic electroluminescent devices. we aligned the p-sexiphenyl(6p) using a simple rubbing treatment. We studied the anisotropic optical properties and electrical characteristics.