Main infrastructures in Korea are maintained according to the result from periodical in-depth inspection. The process is based on the ‘Special Act on the Safety Control of Public Structures’ and accompanied specific guide. The Act has mainly focused on the physical condition and safety of structures up to now. Recently we are faced with the threats coming from aging of structures and climate change. These interior/exterior changes are strong challenges to maintain expected performance of structures. What is more, convenience for people and functionality are came to the fore as important indices. In these circumstances, the government of the Republic of Korea is preparing for a paradigm shift to performance-based maintenance system which can evaluate integral condition of structures with regard to the various performances. In this study, performance indices, detailed inspection items and following inspection techniques are defined. The grade assigning method using the results from inspection and integral evaluation procedure are suggested. This can be used for establishing a improved and long-term maintenance strategy toward an appropriate goal considering various performance characteristics.

Neurokinin B (NKB) and neurokinin B related peptide (NKBRP) belong to tachykinin peptide family. They act as a neurotransmitter and/or neuromodulator. Mutation of NKB and/or its cognate receptor, NK3R resulted in hypogonadotropic hypogonadism in mammals, implying a strong involvement of NKB/NK3R system in controlling mammalian reproduction. Teleosts possess NKBRP as well as NKB, but their roles in fish reproduction need to be clarified. In this study, NKB and NKBRP coding gene (tac3) was cloned from Nile tilapia and sequenced. Based on the sequence, Nile tilapia NKB and NKBRP peptide were synthesized and their biological potencies were tested in vitro pituitary culture. The synthetic NKBRP showed direct inhibitory effect on the expression of GTH subunits at the pituitary level. This inhibitory effect was confirmed in vivo by means of intraperitoneal (ip) injection of synthetic NKB and NKBRP to mature female tilapia (20 pmol/g body weight [BW]). Both NKB and NKBRP had no effect on the plasma level of sex steroids, E2 and 11-KT. However, NKBRP caused declines of expression level of GnRH I, Kiss2 and tac3 mRNAs in the brain while NKB seemed to have no distinct effect. These results indicate some inhibitory roles of NKBRP in reproduction of mature female Nile tilapia, although their exact functions are not clear at the moment.

Acute myocardial infarction (AMI) involving two simultaneous vascular territories of acute transmural ischemia is known as a double or combined myocardial infarction. This well described but extremely rare phenomenon may be related to the fact that AMI with multiple vessel obstruction often causes extensive myocardial injury and death before hospitalization. We reported the first case of 45-year-old man with AMI occluded left anterior descending artery and right coronary artery simultaneously in Korea.

In here, we screened drought tolerant varieties with modified leaf water loss rate assay and visual drought tolerant phenotype in the greenhouse conditions with more than 800 varieties. Among these varieties, Samgang, Gumei4 and Apo showed the lowest of leaf water loss rate and strong drought tolerant phenotype. To identify drought QTLs with Samgang variety, we developed the doubled-haploid (DH) population consist of 101 lines derived from a cross the drought tolerant cultivar Samgang and the drought sensitive cultivar Nagdong. To score the drought phenotype degrees of this population, we withheld water for 6 weeks and treated the watering for 7 days. After watering, visual phenotype was observed 1 to 9 degree according to the standard evaluation system for rice, IRRI. Drought sensitive parent Nagdong was almost died and was scored as 9 degree, while tolerant parent Samgang showed slightly leaf tip drying phenotype and was scored as 3 degree in our experimental conditions. Three main QTLs were detected on chromosome 2, 6, and 11 with this visual phenotype. We also measured relative water contend of these population under drought stress conditions, and got one main QTL on chromosome 11. The QTL loci on chromosome 11 with flanking markers RM26755-RM287 has a function for visual phenotype and relative water content under drought conditions.

Research on salinity stress has strongly increased over the last decade, as salinity stress is a main key factor limiting the global crop production in many regions of the world. In recent years, it is possible to obtain a large amount of genotypic data in a short time due to a reduction in genotyping costs. This wave of genomic information has effected the development of new strategies for the integration of molecular information in breeding programs. However, phenotyping is still a manual activity, and different from each species, environment, and trait. It often generates high labor costs, and can be sensitive to environmental changes, and sometimes includes the individual biased assessments from different people. There is a strong demand for phenotypic data of high quality. The current objective of phenomics is phenotyping a large number of individuals for many traits in a nondestructive manner and with good accuracy. Here we described the image-based technology as applied to alleviate the bottleneck for the development of high-throughput phenotyping platforms. Several trials to measure stress responses of rice plantlets based on image data under the salinity condition are underway to develop automation for the next-level of phenotyping.

Gonadotropin-inhibitory hormone (GnIH) has been found to inhibit the synthesis and release of gonadotropin (GTH) in avian and mammalian species. It was originally identified in the brain of a quail as a novel hypothalamic neuropeptide with a C-terminal Arg-Phe-NH2 motif (RFamide peptide). Homologs of this peptide have been identified in a couple of model fish species such as goldfish (Carassius auratus) and zebrafish (Danio rerio). Understanding GnIH system could be particularly useful in some aquaculture species with problems of frequent reproduction and/or precautious sexual maturation. However, GnIH system in such species has not been studied yet. In this study, we have identified a pupative GnIH gene in the Nile tilapia (Oreochromis niloticus). We also investigated the role of GnIH in the reproduction of this species. The full length sequence of putative tilapia GnIH gene coded for a protein (197 amino acids) containing two modified RFamides (MPLRF and LSQRF) and a LPQRF cDNA sequence of 594 bp. This putative GnIH gene showed high homology with the GnIH genes of Takifugu rubripes (72%) and Tetraodon nigroviridis (74%). PCR analysis showed that expression of this gene was ubiquitously distributed in the whole brain, ovary and testis as well as in the peripheral tissues examined in this study (liver, kidney, intestine, spleen, muscle and gill) except heart and eye. Expression level of this gene in sexually inactive group was significantly higher than the expression level in first gonadal development and sexually active groups (P<0.05). On the contrary, the expression level of LH-β gene was low in sexually inactive group but significantly higher in first gonadal development and sexually active groups (P<0.05). However, no significant difference was observed in the level of FSH-β gene expression between different reproductive phases in this species. In vitro studies revealed an inhibitory effect of GnIH on LH-β mRNA and FSH-β mRNA levels. No significant difference between GnIH and GnIH with LHRH-a treatments on LH-β and FSH-β mRNA expression in female tilapia pituitary cells.

Geneally, rice seeds regardless indica or japonica are showing low germination ratio or completely lost germination ability together with lost of good eating quality under high temperature and humidity conditions. Thus, this study was designed to evaluate a longevity for conservation of good eating quality during long term storage in rice. For the longevity evaluation, germination ability was studied after 5 days of high temperature and humidity stress (50℃/RH 95%). Dharial, originated from Bangladesh and showing weedy type with red pericarp, was selected as a good donor for longevity genes. A mutant was developed from Dharial through EMS mutagenesis and two populations of Dharial/4*Ilmibyeo and Dharial/4*Gopumbyeo were also developed for genetic study. In the 2-DE analysis followed by MALDI-TOF MS with wild and mutant lines, several candidate genes were identified. In the longevity test of two populations, a few lines showing good germination ability after high temperature and humidity stress were selected and subjected to confirm the relationships between longevity and conservation of good eating quality under long term storage.

Near-isogenic lines (NILs) carrying bacterial blight resistance genes (Xa4, xa5 and Xa21) were developed in japonica rice using Suweon345 as genetic background. NILs were selected by gene specific DNA markers and inoculation of K1 or K3a race. NILs conferring Xa4 were resistant to K1, K2, K3, and moderately resistant to K3a. NILs conferring xa5 were resistant to K1, K2, K3, and K3a. NILs having Xa21 were susceptible to K1, while resistant to K2, K3 and K3a. Target genes of NILs with the genetic background of Suweon345 were also confirmed by using eleven Philippines races and International Rice Bacterial Blight (IRBB) NILs carrying Xa4, xa5 and Xa21. All NILs had no significant difference from their recurrent parents in the major agronomic traits except for panicle length and brown rice 1,000 grain weight. Heading date of NILs ranged from Aug. 10 to Aug. 11, which was similar to that of recurrent parent, Suweon345. Culm length, number of grains per panicle and ratio of ripened grain of NILs were similar to those of Suweon345. Milled rice of NILs was ranged from 4.82 to 4.93MT/ha. These NILs will be useful for improving resistance to K3a race of bacterial blight pathogens in Korean japonica cultivars.

Apricot (Prunus armeniaca L.) cultivars show a gametophytic self-incompatibility (GSI) system, like other fruit species of Rosaceae family. Thus, it is necessary to determine their S-genotypes in order for stable fruit set in commercial cultivation. S-genotypes of apricots were determined by PCR and test crosses. Three sets of consensus primers designed from Prunus S-RNases were used to amplify fragments containing the first and second S-RNase intron, respectively. Through the results obtained from the 3 PCRs, we could identify SI genotypes of 33apricot cultivars. Several cultivars such as 'Heiwa', 'Yamagata No.3' and 'Shinsuoomi' had the self-compatible (Sc) allele. Self-pollination tests revealed that cultivars with Sc allele were self-compatible. Cross-pollination tests confirmed that there was cross-incompatibility between the cultivars with the same S-genotypes. These results might be very useful for growers for effective pollination and for breeders using these in cross breeding programs.

Fish reproduction is influenced by various external environmental factors. Among these factors, changes of photic conditions are thought be most closely related to the reproduction of many fish species. In recent studies, melatonin that mediates the changes of photic condition outside has been used in an attempt to get a similar effect to photoperiod manipulation without changing photoperiod. However, the effects of exogenous melatonin vary depending on life stages. We have previously investigated the effect of melatonin on reproductive activity in mature Nile tilapia (Oreochromis niloticus). In this study, effects of exogenous melatonin on the spawning activity, the rate of mouth brooding success rate and early survival rate of lavae produced from melatonin treated Nile tilapia were investigated. Nile tilapia at the time of puberty were randomly divided into three groups and fed on control (0 ㎍/g), low-dose melatonin (2.5 ㎍/g BW) or high-dose melatonin (25 ㎍/g BW) diet. Fish were reared indoor tanks at 27～28℃ under natural-photoperiod and fed twice a day at 10:00 and16:00 during the experiment (120 days). Fish were sampled to examine growth and gonadal development on Day 30, 60, 90 and 120. There were no significant differences of somatic growth between control (no melatonin) and melatonin-treated groups, indicating that melatonin administration did not cause any negative effects on the growth of experimental fish. The patterns of gonadal development were almost the same between control and melatonin-treated groups. In juvenile tilapia, treatment with low-dose melatonin resulted in the increase of spawning rate, the rate of mouth brooding success and early survival rate of laval tilapia. However, high-dose melatonin resulted in the decrease of spawning rate, the rate of mouth brooding success and early survival rate of laval tilapia, although the earliest spawning occurred in one of the high-dose group fish. Fish in high-dose melatonin group failed to recover from reproductively suppressed state even after the cease of melatonin treatment, indicating that too much melatonin might act negatively on spawning activities and gonadal maturation in Nile tilapia. In conclusion, the results from this study suggest the possibility that a pertinent dose of melatonin treatment can effectively accelerate the spawning rate and the rate of mouth brooding success, and bring positive effects on early survival rate of tilapia lavae.

Photoperiod is known to be the most potent environmental stimulus for reproduction in many lower vertebrates, and it exerts an endogenous effect by causing a rhythmic change in melatonin level, which increases during the dark phase and decreases during the light phase. In recent studies, melatonin administration was capable of changing seasonal reproductive activities in several fish species, and also resulted in modulating the timing of smoltification in a salmonid fish (Amano et al., 2004; Ligo et al., 2005). In this study, we have investigated the changes of spawning activities (number of eggs, frequency of spawning) by oral administration of melatonin in the Nile tilapia, Oreochromis niloticus. Fish were obtained from a local fish farm (Chungju, Chung Buk) and acclimatized in fish rearing facilities in Sunmoon University (Asan, Chung Nam). Randomly selected 24 fishes (12 males, 12 females; 200～400 g in body weight, BW) were divided into three groups and each fish was accommodated into glass aquarium individually. Fish were fed either with control diet (0 ㎎ melatonin) or low-dose melatonin diet (0.3 ㎎ melatonin/㎏, BW) or high-dose melatonin diet (3 ㎎/㎏, BW). Fish were individually checked everyday for the presence of eggs in their mouths, and the eggs were removed and counted when found. Fish were fed twice a day, but melatonin treated diet was given only once a day at 10:00a.m.. The daily feeding ration was set at 2% of the body weight so that the fish ate all the pellets provided. Fish were sampled for blood parameters (Hb, Glu, GOT, GPT) on March 2 (Day 30), April 2 (Day 60), May 3 (Day 90), June 3 (Day 120) and July 14 (Day 160). The sampling was done between 14:00 and 16:00 p.m.. For the sampling, fish were anesthetized in 50 ppm benzocaine, and body length (BL) and BW were measured. Blood sample was collected using a heparinized syringe from the caudal blood vessel. Melatonin affects several photoperiodic signals including reproductive activities in fish. Low-dose melatonin administration appeared to disturb spawning and sexual maturation in Nile tilapia in this study. Fish treated with low-dose melatonin spawned less numbers of egg than the fish treated with high-dose. In contrast, high-dose melatonin administration caused more frequent spawning than low-dose melatonin. On the other hand, somatic growth and blood parameter were not affected by melatonin treatments. These results suggest that pertinent melatonin could be involved in providing photoperiodic information as short day photoperiod. Fish treated with over dose melatonin seemed to have no melatonin-free interval. In that circumstance the melatonin message might have not been conveyed as a proper signal.

A new yellow waxy corn hybrid "Daehakchal Gold 1" was developed from single cross between Yeongdeok Jaera and Okchen Jaera at Chungnam National University in 2007. Inbred CNU57 derived from Yeongdeok Jaera was used as the seed parent of Daehakchal Gold 1, and inbred CNU 27 derived from Okchen Jaera as the pollen parent. Tasseling date of this hybrid was seven day later than that of check hybrid, Chalok 1. Daehakchal Gold 1 was 19.7cm in ear length and 4.5cm in ear diameter. The yield of Daehakchal Gold 1 and check hybrid in dry matter were 146.5g and 113.9g per plant, respectively. On yield trial, which were increased 29.7% compared with a check hybrid, Chalok 1. Especially, Daehakchal Gold 1 had yellow kernels and good eating quality. The ratio of kernel set length/ear length was similar to Chalok 1. It is moderately resistant to Bioporalis maydis and corn borer. The yields of Daehakchal Gold 1 in fresh ear weight and in number of fresh ear were 16% and 8%, respectively, higher than those of a check hybrid in regional yield trials for three years. Seed production of this hybrid has gone well due to good match during crossing between seed and pollen parents.