A new WRKY transcription factor gene was isolated by ESTs screening from a cDNA library of suspension cultured cells of Sweet potato (Ipomoea batatas). The 2,285 bp cDNA fragment, IbWRKY, was sequenced, from which a 505 amino acid residue protein was deduced. A search of the protein BLAST database identified significant similarity to other plant WRKY31 protein sequences. RT-PCR analysis showed expression patterns of IbWRKY31 in various intact tissues and suspension cultured cells of Sweet potato, and in leaves exposed to different stresses. The IbWRKY31 gene was highly expressed in suspension cultured cells. In leaf tissues, IbWRKY31 showed strong expression during salicylic acid and methyl jasmonate treatments. Expression of IbWRKY31 was also induced under various abiotic stress and pathogen infection conditions, such as wounding, H2O2, MV, PEG, NaCl, and bacterial pathogen infection. These results suggest that IbWRKY31 is involved in plant responses to various stress conditions, such as abiotic stresses and pathogen infection through a defense signaling pathway.

This study compares the differences in the gastrointestinal transit time between the conventional capsule endoscope and a minimized capsule endoscope model in normal dogs to verify whether the minimization of capsule endoscope can help relief retention in the gastrointestinal tract, especially in the pyloric passage. Three male beagles were used as the experimental group for which the minimized capsule endoscope model was orally administered and the control group consisted of three beagle dogs for which the conventional capsule endoscope was orally administered. Nine experiments were conducted with three experiments for each dog in each group. The results showed a significant difference in the gastric transit time (GTT) by the minimization of the capsule endoscope between the two groups (control group: 123.3 ± 80 min, experimental group: 63.3 ± 40.9 min, p=0.019). In contrast, the difference in the small bowel transit time (SBTT) by the minimization of the capsule endoscope between the two groups (control group: 86.6 ± 58.9 min, experimental group: 80 ± 33.5 min, p=0.863) was not significant. In this study, the capsule endoscopes reached the large intestine without retention in the small intestine in all subjects. The significant difference in the GTT between the control group using the conventional capsule endoscope and the experimental group using the minimized capsule endoscope model suggests that the smaller size of the capsule endoscope is helpful in resolving retention in the gastrointestinal tract, thus shorting the GTT.

Endoplasmic reticulum (ER) stress is well known as a suppressor in osteoblast differentiation and activating transcription factor 3 (ATF3) could be induced by a various extracellular signals including cytokines, hormones, DNA damage. Up to date, although the role of ATF3 have been studied, the function of ATF3 in osteoblast differentiation is still not clear yet. Our study showed that expression level of ATF3 could be incresed by tunicamycin which is ER stress inducer in preosteoblasts. BMPs, which are secreted by osteoblasts, can be important regulators in osteogenic differentiation. The stress-responsive transcription factor ATF3 is a negative regulator of osteoblast differentiation in MC3T3-E1 cells. In this study, we verified that BMP2-stimulated osteoblast differentiation could be inhibited by over-expressed ATF3 through regulating alkaline phosphatase (ALP) expression and activation.

CCD photometric observations of the globular cluster (GC), M53 (NGC 5024), are performed using the 1.8 m telescope at the Bohyunsan Optical Astronomy Observatory in Korea on the same nights (2002 April and 2003 May) as the observations of the GC M92 (NGC 6341) reported by Cho and Lee using the same instrumental setup. The data for M53 is reduced using the same method as used for M92 by Cho and Lee, including preprocessing, point-spread function fitting photometry, and standardization etc. Therefore, M53 and M92 are on the same photometric system defined by Landolt, and the photometry of M53 and M92 is tied together as closely as possible. After complete photometric reduction, the V versus B − V , V versus V − I, and V versus B − I color-magnitude diagrams (CMDs) of M53 are produced to derive the relative ages of M53 and M92 and derive the various characteristics of its CMDs in future analysis. From the present analysis, the relative ages of M53 and M92 are derived using the
(B − V ) method reported by VandenBerg et al. The relative age of M53 is found to be 1.6 ± 0.85 Gyr younger than that of M92 if the absolute age of M92 is taken to be 14 Gyr. This relative age difference between M53 and M92 causes slight differences in the horizontal-branch morphology of these two GCs.

A search for hot and bright white dwarfs (WDs) in the Milky Way globular clusters M13 (NGC 6205) and M22 (NGC 6656) is carried out using the deep and homogeneous V I photometric catalog of Anderson et al. and and Sarajedini et al., based on data taken with the ACS/WFC aboard the Hubble Space Telescope (HST). V versus V − I color-magnitude diagrams (CMDs) of M13 and M22 are constructed and numerous spurious detections are rejected according to their photometric quality parameters qfit(V ) and qfit(I). In the case of M13, further radial restriction is applied to reject central stars with higher photometric errors due to central crowding. From each resultant V versus V −I CMD, sixteen and thirteen WD candidates are identified in M13 and M22, respectively. They are identified as stellar objects in the accompanying ACS/WFC images and are found to be randomly distributed across the central regions of M13 and M22. Their positions in the CMDs are in the bright part of the DA WD cooling sequences indicating that they are true WDs. In order to confirm their nature, follow-up spectroscopic observations are needed.

A search for luminous white dwarfs (WDs) in several nearby Galactic globular clusters (GCs) was carried out using the deep and homogeneous photometric catalog of Galactic GCs taken with the ACS/WFC aboard the Hubble Space Telescope (HST) by Sarajedini et al. and Anderson et al.. It resulted in the identification of luminous WD candidates in the GCs M13 (NGC 6205) and M22 (NGC 6656). The purpose of the present study is to identify luminous WDs in the deep and homogeneous V versus V - I color-magnitude diagrams (CMDs) of several nearby Galactic GCs taken with the ACS/WFC aboard the HST. Using photometric data for the GCs M13 and M22 that are now in the public domain, the V versus V - I CMDs of the GCs M13 and M22 were constructed. Many spurious detections in the CMDs were removed using the photometric quality parameters qfit(V ) and qfit(I), and a radial restriction was applied to the CMDs to remove the central stars with higher photometric errors due to central crowding. From each resultant V versus V - I CMD of the GCs M13 and M22, a dozen or so luminous WD candidates were identified. They were confirmed as stellar objects in the accompanying ACS/WFC images and their positions in the CMDs were in the bright part of the DA WD cooling curve. Therefore, the luminous WD candidates in the GCs M13 and M22 seem to be true luminous WDs, and spectroscopic observations are needed to confirm their true identity.

Intermediate disturbance hypothesis is one of important hypotheses for presenting the diversity patterns under disturbances. To investigate the diversity patterns of benthic macroinvertebrate communities under various disturbances, we collected macroinvertebrates in 47 sites representing various habitat types as well as pollution gradients in Southeastern Korea in summer and winter. Environmental variables such as depth, velocity, substrate and conductivity, and biological water quality indices (e.g., BWMP) were measured to show the intensity of disturbance in each site. Species abundance distributions (SADs) which are one of the efficient ways to assess community structure states based on macroecology were also considered to represent the pollution status based on the community patterns along an established pollution gradient. The community patterns were broadly divided into log-normal distribution and geometric series groups according to SAD models with weak and strong disturbance, respectively. According to the application of physicochemical water quality variable (conductivity), the gradient of community indices showed higher values on the intermediate disturbance state. Higher values of community indices, however, were presented on the low disturbance state with the gradient from BMWP. The parameters of SAD models, log-normal distribution, γ, and geometric series, k, were additionally calculated and compared with the traditional community indices.

In the present work, exfoliated graphite nanoplatelets (EGN) of 1 μm in average particle size, which were prepared by heating at 900℃ and then subjected to ultrasonic, ball-milling, and vibratory ball-milling techniques, were uniformly incorporated into phenylethynyl-terminated polyimide (PETI-5) resin. The fracture surface morphology and the electrical resistivity of the EGN/PETI-5 composites were investigated. The results showed that the fracture surfaces and the electrical resistivity strongly depended on the EGN content. The fracture surfaces became more ductile and roughened with increasing EGN and the electrical resistivity was gradually decreased with increased EGN loading, indicating the percolation threshold at 5 wt% EGN.

In this present work, the effect of additional heat-treatment (AHT) in the range from 1800℃ to 2400℃ on the chemical composition, morphology, microstructure, tensile properties, electrical resistivity, and thermal stability of commercial polyacrylonitrile (PAN)-based carbon fibers was explored by means of elemental analysis, electron microscopy, X-ray diffraction analysis, single fiber tensile testing, two-probe electrical resistivity testing, and thermogravimetric analysis (TGA). The characterization results were in agreement with each other. The results clearly demonstrated that AHTs up to 2400℃ played a significant role in further contributing not only to the enhancement of carbon content, fiber morphology, and tensile modulus, but also to the reduction of fiber diameter, inter-graphene layer distance, and electrical resistivity of "as-received" carbon fibers without AHT. The present study suggests that key properties of commercial PAN-based carbon fibers of an intermediate grade can be further improved by proprietarily adding heat-treatment without applying tension in a batch process.

Benthic macroinvertebrates are considered as a representative group in presenting ecological states and water quality in freshwater ecosystems. Although much study has been not conducted in stream, relatively few cases were comparatively reported in community responses to disturbances in lake and stream. Benthic macroinvertebrate were sampled in 12 lakes and 8 streams in different trophic and saprobic state. The sampled communities were accordingly grouped according to degree of disturbance. Species abundance distribution (SAD) was used for illustrating ecological states, and the fitness was accordingly checked with the proposed models. SADs were divided according to saprobic states in stream while SADs were clearly separated based on trophic levels