The mechanical properties and microstructures of Aluminum 6056 alloys were investigated for their use in the fabrication of a piton block. The EN-AW6056 alloys exhibited a tensile strength of 375 MPa for a solution treatment temperature of 550 oC for 2 h followed by an aging treatment at 190 oC for 4 h. The microstructures of the heat treated specimen showed that the Mg2Si phase with a size of 3~5 um was dispersed throughout the aluminum matrix when the heat treatment was done. Moreover, in order to identify the forgeability of the specimen, upsetting tests were done. For up to 80 % of the upsetting ratio, the specimen maintained its original shape, and at above 80 % of the upsetting ratio, the specimen underwent crack development. The specimen was successfully forged without any defects with the examined material conditions. The material conditions together with the forging conditions are discussed in terms of the microstructures and mechanical properties.

We sequenced the complete mitochondrial (mt) genome of Camponotus atrox (Hymenoptera: Formicidae) that is distributed only in Korea. This genome is 16,540 bp in size, contains typical sets of genes (13 protein-coding genes, 22 tRNAs, and two rRNAs). The C. atrox A+T-rich region is the longest in the sequenced ants as 1,402 bp and is comprised of an identical tandem repeat consisting of six 100-bp copies and one 96-bp copy. A total of 315 bp of intergenic-spacer sequences were spread over 23 regions. An attempt to align spacer sequences in ants turned out that alignment was mostly feasible among congeneric species, with a substantial sequence divergence, indicating the potential of these sequences as congeneric molecular markers. The A/T content in first and second codon positions of PCGs are similar in ants including C. atrox (73.9 vs. 72.3% on average). Estimation of degree of genetic divergence (e.g. non-synonymous substitution rate) with an increased taxon sampling among hymenopteran superfamilies indicated the presence of different rates of divergence between the suborders Symphyta and Apocrita as has previously been reported. The C. atrox mt genome has a unique gene arrangement, trnI-trnM-trnQ at the A+T-rich region and ND2 junction (underline for inverted gene), possibly originated from tandem duplication of trnM-trnI, resulting in trnM-trnI-trnM-trnI-trnQ and loss of first trnM and second trnI, resulting in trnI-trnM-trnQ.

Multiple starters consisting of two Bacillus amyloliquefaciens strains (MJ1-4 and EMD17), Pichiafarinosa SY80, and Rhizopus oryzae were used for Doenjang making. Bacillus strains were selected based on their abilities to inhibit toxinogenic fungi and Bacillus cereus, fibrinolytic activity, and their ability to confer good flavor to Cheonggukjang. P. farinosa SY80 and R. oryzae, previously isolated from soy sauce, were selected because they were not inhibited by two bacilli. Doenjang was prepared by inoculation of multiple starters (A1 Doenjang). Control Doenjang was prepared by inoculation of B. subtilis KACC 16750 (Natto strain) and Aspergillus oryzae KCCM 60166 (A2 Doenjang). Another control (A3 Doenjang) was prepared by inoculation of microorganisms present in rice straw. Doenjang samples were fermented for 70 days at 20℃. pH of 3 samples decreased from the initial value of 6.4 to 5.8~6.0 and titratable acidity (TA) increased from 0.6 to 1.1~1.3. The amount of amino-type nitrogen increased during fermentation. There were slight differences in moisture, crude-protein, and crude-fat contents after 70 days. Contamination of fungi was observed only in A3 Doenjang and B. cereus was not detected from all 3 samples. A1 Doenjang showed the highest fibrinolytic activity and A2 Doenjang the second. These results indicate that Doenjang made with carefully selected starters was functionally improved and microbially more safe.

Seed color is an important factor affecting physiological and developmental process in wheat. One of the plant pigments, anthocyanins are a group of flavonoid compounds well known as pigments responsible for blue, purple, red, or yellow coloration of plant tissues. In this study, we investigated the pigmentation of purple and yellow color seed according to wheat grain developmental stages. The contents of anthocyanin and chlorophyll in the purple and yellow seeds were measured. Chlorophyll contents were changed similarly in both purple and yellow color seed, and no significant difference was observed between them. In purple color seed, the content of anthocyanin was significantly induced compared with yellow color seed. The individual anthocyanin components were investigated by ultra performance liquid chromatography (UPLC). Cyanidine-3-glucoside (C3G) and peonidine-3-glucoside (P3G) were detected as predominant anthocyanin in purple color wheat. To investigate whether structural genes in anthocyanin biosynthesis were involved in the trait differences between purple and yellow color seed, we examined the expression of anthocyanin biosynthesis-related genes (CHS, CHI, F3H, DFR, ANS, UFGT) and MYB transcription factor in developing wheat grains by using qRT-PCR. This study indicates that the expression of anthocyanin biosynthesis-related genes and MYB transcription factors correlate with anthocyanin levels of grain.

Gamma irradiation has been used as a tool for plant mutation breeding to select new cultivar with improved characteristics. Generally, the irradiation of seeds with high doses of gamma rays disturbs the synthesis of protein, hormone balance, and enzyme activity. And also, high dose of gamma rays to reduce plant height, number of tiller, and root length, although the effect of gamma-irradiated plants may depend on the species and cultivar or stress conditions. Biological effects of radiations can be divided into two types according to dose range and periods of exposure. Acute irradiation represents exposure to high-dose of irradiation over short period time, whereas the chronic irradiation is comprised of exposure to low doses of radiation over extended period of time. To compare the effects of acute and chronic exposure to ionizing radiation on two wheat cultivars (K4191 and Geumgangmil), we measured their germination rate, seedling height, and root length. In order to understand the influence of antioxidant-related genes and DNA repair-related genes, we used qRT-PCR methods to identify their expression levels. To study the behavior of a radiation-induced free radical, gamma-irradiated seeds were used for ESR spectroscopy. Plant growth pattern was showed positive correlation with ESR results. This study indicates that low level chronic radiation exposure is even more serious effects than short doses of high level radiation according to different wheat cultivar.