Aluminum (Al) is one of the most widely applied metals in various industries. Anthropogenic activities of industrial waste result in increased accumulation of Al in natural water resources and aqueous organisms, leading to increased heavy metal pollution in the environment. This will ultimately associate with health risks to all living beings including humans. The present study addresses the possible toxic effects of Al on the motility and regeneration of planarians, using Dugesia japonica as the experimental animal model. Planarians were exposed to varying concentrations of Al (50–1,200 mg/L) for 1 hr, and subsequently evaluated for their motility, seizure-like behaviors, regeneration and alterations of the cell-organelles in their body. Results of the study exhibit that increasing Al concentrations lead to decreased motility and increased seizure-like behaviors, especially the c-type and head bob behaviors in planarians (p<0.05). The regeneration ability in the tail segments was reduced by increased Al concentrations, and the eyespot and optic nerves were more clearly observed in the control groups than planarians exposed to Al. Organelle analysis revealed morphological abnormalities in the mitochondria, golgi apparatus, endoplasmic reticulum, and cilia in the head region of planarians, as compared to the control groups. Taken together, our results indicate that exposure to Al alters the behavior of planarians and delays the regeneration of amputated body parts. Therefore, we suggest that Al exposure adversely can affect the lives of aquatic organisms, and induce toxicity such as cell abnormalities in animals.

Lead (Pb) is a major heavy metal that augments environmental pollution and is a health risk to living organisms. This study was performed to investigate the effect of lead on characteristics of planarian, Dugesia japonica. Briefly, planarians were cultivated in water containing different concentrations (0–400 mg/L) of Pb, and incubated for varying durations (1, 3, and 5 hr). After termination of the incubation time, motility and seizure-like behaviors (c-like, head-bop, snake-like, and screw-like) of the planarians were counted in fresh water. Results showed that increasing Pb concentration and time resulted in decreased motility of the planarians (p<0.05). Increasing concentrations of Pb also resulted in significant increase in the seizure-like behavioral patterns, in particular the c-like and head-bop behaviors. In order to examine eye regeneration, the head region was cut, and rest of the body was incubated in water in the absence or presence of Pb, until emergence of the eye extrusion. Formation of eye spots was initiated in amputated fragments of the control group (without Pb) on day 4 after incubation, whereas appearance of the eye spots was delayed in planarian exposed to 200 mg/L Pb. Moreover, immunohistochemistry revealed that formation of the optic nerve was delayed in planarians exposed to Pb. Thus, our studies determined that planarians exposed to high concentrations of Pb resulted in decreasing motility and induction of seizure-like behaviors, as well as delayed eye regeneration. Results of the current study therefore validate that exposure to lead has a negative effect on the lifespan of aquatic organisms and can cause disturbance of the nervous system in animals, thereby implying the possibility of threatening health.

This study was undertaken to evaluate the toxic effect of cadmium sulfate (Cds) on planarians (Dugesia japonica), and the suitability of planarians as an alternative animal model for toxicity studies. Planarians were exposed to varying concentrations of experimental solutions containing 0.1–25 mg/L Cds, and incubated for 1, 3, and 5 hrs. Motility, seizure-like behaviors (c-like, head-bop, snake-like, and screw-like) and regeneration ability of the amputated fragment were subsequently evaluated. Results showed decreased motility with increasing concentrations of Cds (p<0.05), with the lowest motility being observed at the highest concentration of 25 mg/L Cds. Results also indicate that seizure-like behavior patterns were significantly affected by increments in the Cds concentrations, especially the c-like and head-bop behaviors were notably increased. Compared to the control, the regeneration ability of the planarians was decreased in the experimental solutions containing Cds. Planarians exposed to Cds showed either delayed eye formation or no eye regeneration during incubation. Moreover, increased concentrations of Cds resulted in failure to regenerate and death of the planarians. In conclusion, this study confirm that the heavy metal Cds exerts a toxic effect on planarians. Furthermore, the performances of the planarians in the experimental period exhibit their suitability as an alternative animal model for toxicity studies.

Nicotine is a component of tobacco products and is one of the most commonly abused substances that leads to addiction. Therefore, the present study was performed to investigate the behavioral pattern and toxicity by nicotine exposure in planarians. Basically, planarians were exposed to different concentration of nicotine for 5 min. To investigate detoxification effect, planarians were exposed to nicotine for 5 min, and treated glycyrrhizin for 5 min, then motility and seizure-like behavior were observed for 5 min. As a result, the motility of nicotine-exposed planarians decreased approximately more than 50% compared to freshwater control. However, the motility of glycyrrhizin-exposed planarians recovered than nicotineexposed planarians. In the assessment of seizure-like behavioral pattern, planarians exposed to nicotine showed head-bop or c-like type rather than screw-like or snake-like patterns. However, planarians exposed to glycyrrhizin showed no seizure-like behavior. To examine the oxidative stress response, planarians were cultured in fresh water containing 1 mM nicotine for 1 day. Planarians were homogenized and extracted to assay the contents of reactive oxygen species (ROS), lipid hydroperoxides (LH), glutathione (GSH), catalase (CAT), and superoxide dismutase (SOD). The result showed that a significantly higher level of ROS, LH indicated in planarians exposed to nicotine, on the other hand, glycyrrhizin-exposed planarians were significantly decreased ROS, LH levels. In conclusion, the motility decreased when planarians were exposed to nicotine, in a dose-dependent manner, whereas seizurelike behavior increased. Nicotine induced behavioral disturbances and cell toxicity in planarians were recovered by glycyrrhizin, suggesting a candidate substance for nicotine addiction treatment.

Background: Rasch analysis has the advantage of placing both the items and the person along a single ratio scale and calibrates person ability and item difficulty onto an interval scale by logits. Therefore, Rasch analysis has been recommended as a better method for evaluating functional outcome questionnaires than traditional analyses. Objects: The aim of current study was to investigate item fit, item difficulty, rating scale, and separation index of the Korean version of the Fullerton Advanced Balance (KFAB) scale using Rasch analysis. Methods: In total, 93 patients with stroke (male=58, female=35) participated in this study. To investigate the item fit, difficulty, rating scale, and separation index of the KFAB scale, Rasch analysis was completed by the Winsteps software program. Results: In this study, all items of the KFAB scale were included in the Rasch model. The most difficult item was ‘standing with feet together and eyes closed’, and the easiest item was ‘two-footed jump’. The rating scale was a 4-point scale instead of the original 5-point scale. Person and item separation indices showed high values that can identify a person with a wide range of balance ability. Conclusion: The KFAB scale appears to be a reliable and valid tool to assess balance function in patients with stroke. Furthermore, the scale was found to discriminate among stroke patients of varying balance abilities.

Dry sliding wear behavior of electro-pressure sintered Co-Fe, Co-Ni and Co-Fe-Ni compacts was investigated. Pin-on-disk wear tests were performed on the sintered compacts disk specimens against alumina and silica ball counterparts at various loads ranging from 3N to 12N. Two sliding speeds of 0.1m/sec and 0.2m/sec and a fixed sliding distance of 1,000m were employed. Worn surfaces and cross sections of them were examined by a scanning electron microscopy, and wear mechanism of the compacts was investigated. Effects of the oxide layer that was formed on wearing surface of the compacts on the wear were also studied.

Bulk amorphous materials have been intensively studied to apply for various advanced industry fields due to their high mechanical, chemical and electrical properties. These materials have been produced by several techniques such as mechanical alloying, melt spinning and gas atomization, etc. Among them, the atomization is the most potential technique for commercialization due to high cooling rate during solidification of the melt and mass productivity. However, the amorphous powders still have some limitations because of their low ductility and toughness. Therefore, intensive efforts have to be carried out to increase the ductility and toughness. In this study, the Ni-based amorphous powder was produced by the gas atomization process. And in order to increase the ductile toughness, ductile Cu phase was coated on the Ni amorphous powder by spray drying process. The characteristics of the as-synthesis powders have been examined and briefly mentioned. The master alloy with Ni57Zr20Ti16Si2Sn3 was prepared by vacum induction melting furnace with graphite crucible and mold. The atomization was conducted at 1450oC under the vacuum of 10-2 torr. The gas pressure during atomization was varied from 35 to 50 bars. After making the Ni amorphous powders, the spray drying was processed to produce the Cu -coated Ni amorphous composite powder. The amorphous powder and Cu nitrate solution were mixed together with a small amount of binder and then it was sprayed at temperature of 130oC and rotating speed of 15,000 R.P.M..

The microstructure and mechanical properties of the hypereutectic prealloyed Al-Si powders prepared by the gas atomization process were described in this paper. With increasing the gas pressure of the atomization, the average powder size was decreased from about . The primary eutectic Si particles were uniformly distributed in the Al matrix and their size varied in the range of . The high densified specimens with above 96% of the theoretical density were fabricated the hot pressing process. The UTS mechanical properties of VN1 specimens were much higher than that of conventional hypoeutectic Al-Si alloys.

Common wheat has complex genome composition of homoeologous hexaploid (AABBDD, 2n = 6x = 42) and each homoeologous genome has high similarity. Due to these complexity, wheat genome study is a large challenge to researchers for genomic and genetic study. We analyzed expressions of individual wheat genome and rye genome specific transcripts using custom array with 2BS.2RL wheat-rye translcoation. Genomic probes were synthesized within each diploid progenitors (AA, BB, DD, 2n = 14, respectively) of wheat, common wheat, and rye (RR, 2n = 14). Total RNA isolated from seedlings of T. urartu, Ae. speltoides, Ae. squarrosa, ‘Chinese Spring’, ‘Chaupon’, and 2BS.2RL were hybridized on arrays. Each homoeologous gene differentially expressed in hexaploid wheat and rye were identified on the custom array and the transcripts were clustered based on hybridization values. qRT-PCR was performed to verify the custom array result with a set of five genes by highly replicated experiments (three biological and three technical replications). The qRT-PCR results demonstrated genome specific expression of five genes in sympathy with array results. Here we provide information of each individual genome specific transcripts and it will we a useful data to study complex wheat genome compositions.

In order to breakthrough upcoming challenges for the food production, the efficient use of rice germplasm would be a indispensible. These rice germplasm, adapted from diverse eco-systems, are undiscovered treasures for rice breeders/researchers, potentially providing a broad array of useful alleles that enrich gene pools of current cultivated rice varieties. Although growing ex-situ conservation efforts are an important for preserving diverse rice genetic resources, the activity on finding the novel and favorable genetic variants from the vast genebank collection is greatly challenging, requiring extensive screening processes. Therefore, rice core collection is a powerful solution to accelerate utilizations of the exotic germplasm of the entire population. In addition, The application of whole genome re-sequencing technology would establish a potent platform for fast forward genetic study, such as genome wide association study (GWAS). The GWAS has been implemented to efficiently identify candidate genes related to various useful agricultural traits in many crop species including rice. Given the significant associations between genetic variations and phenotypic diversity does not require prior knowledge, GWAS using high genome coverage of SNP markers provides a genomics platform to dissect previously unknown adaptive or other useful genetic variation accumulated in plant germplasm resources over the times. Once pinpointing candidate genes, GWAS allows informed choice of parents for QTL analysis based on the haplotype information, along with suggesting targets for following mutagenesis and transgenics. Here, we are to report our current achievements and perspectives from GWAS and post-GWAS undertaken to dissect and exploit useful alleles underlying many agricultural traits from Rice core set, including PHS (Pre-Harvest Sprouting), salt tolerance and disease resistance and so forth. Also, we will introduce the integrated Omics based GWAS case study using transcriptomes, proteomes, metabolomes and ionomes of our rice core set.

Genetic resources play a great role in crop breeding because of containing a broad array of useful genes. Currently, the harder are rice breeders trying to develop new rice cultivars with the improved traits, they are more often handicapped by the limited availability of germplasm resources. Thus, a desirable core or heuristic (HS) set of germplasm with maximum genetic diversity can be usefully exploited to breakthrough the present and future challenges of the rice breeding. As such we previously developed the rice HS sets of 166 diverse accessions out of a total 24,368 rice germplasms. Here, we report a large-scale analysis of the patterns of genome-wide genetic variations accumulated in the HS as well as Korean rice over the time. We characterized a total of about 11.8 millions of single nucleotide polymorphisms (SNPs) across the rice genome from resequencing a total of 295 rice genomes including 137 HS and 158 KB rice sets, with an average of approximately 10x depth and > 90% coverage. Using about 460,000 high-quality SNPs (HQSNPs), we specified the population structure, confirming our HS set covers all the rice sub-populations. We further traced the relative nucleotide variabilities of HQSNPs and found the level of the diversity was dynamically changing across the KB genome, which reveals the selection history of KB lines in the past and present. In addition, the results of our genome wide association study (GWAS) suggests that our HS can be also a good reservoir of valuable alleles, pinpointing those alleles underlying the important rice agronomical traits. Overall, the resequencing of our HS set re-illuminates the past, present of the germplasm utilization, which will support the Korean rice breeding in the future.

Sequence-tagged site (STS) markers tightly linked to the bacterial leaf blight (BLB) resistance genes, xa5, xa13 and Xa21, were used in this study. A survey was conducted to find polymorphisms between the resistant and susceptible germplasm in rice. 500 of Korean varieties and 100 of landraces were evaluated in this study. STS marker, RG207 was used to having xa5 resistance gene of rice germplasm. 27 varieties of Korean germplasm showed resistant for xa5 gene. The RG136 an xa-13 marker resulted in a single band of approximately 1kb in all the rice accessions studied. In order to detect polymorphism, digestion of the polymerase chain reaction (PCR) product was performed using a restriction enzyme Hinf Ⅰ. The resistant lines resulted in two bands 0.5kb on digestion with Hinf Ⅰ, while the same enzyme did not digest the PCR product of susceptible lines. No polymorphism was detected in Korean varieties and landraces, indicating that they probably do not contain xa13 gene. pTA248 an Xa-21 marker detected a band of 1kb in the resistant lines and bands of either 750bp or 700bp in the susceptible lines. Among germplasm tested, there are no varieties and landraces with Xa21 resistant gene. The results of the germplasm survey will be useful for the selection of parents in breeding programs aimed at transferring these bacterial blight resistance genes from one varietal background to another.

Genetic background and phylogenetic relationships among 20 Korean wheat cultivars were assessed using microsatellites after amplifying with 13 SSR primer pairs. Average allele number per primer pair was 3.36. Genetic similarities for every pair of cultivars ranged from 0.42 to 0.97, with 0.69 of overall average. Korean cultivars were divided into two major groups based on microsatellite DNA polymorphisms. Group I consisted of relatively old cultivars developed until 1970s, and group II contained the recent cultivars developed during 1980s and 1990s. Amongst old elite cultivars/lines, ‘Yukseung 3’, ‘Norin 12’ and ‘Norin 72’ contributed most to the genetic background of cultivars belonging to group I, and ‘Norin 4’, ‘Norin 12’, ‘Norin 43’ and ‘Norin 72’ to group II, respectively. The phylogenetic relationship of Korean wheat cultivars was in accordance with the genealogical data of each cultivar. The genetic background of each cultivar was assessed from the point of breeding and germplasm management such as variety identification and duplicated accessions for assisting in developing a system for the registration of new variety based on the molecular characterization in future.

운동학습에서 실험적 연구를 통한 무작위 연습의 효과가 파지검사와 전이검사에서 입증되고 있지만 스포츠 현장에 적용되어 연구된 사례는 제한적이다. 맥락간섭의 효과가 스포츠 현장에 적용되어 연구되고 일반화된 분야로는 라이플 사격, 배드민턴 서브, 배구기술, 카약의 롤 기술, 스노우보드 기술, 그리고 야구기술 등이 있다. 본 연구는 맥락간섭의 효과가 골프의 퍼팅기술에 적용될 수 있는지를 검증하고자 하였다. 골프의 퍼팅은 지속적으로 정확한 수행을 요구하는 동작으로 골프 경기의 점수를 줄이는데 기여할 수 있는 매우 중요한 기술이다. 또한, 골프의 퍼팅은 수행시마다 조건이 다른 수행간의 가변성을 지니고 있음에도 불구하고 대부분의 골퍼들은 분단적 연습이라고 불리는 형식의 방법으로 퍼팅연습을 하고 있기 때문에 분단적 연습 보다는 무작위 연습이 더 효과적이라는 가정을 가지고 연구를 수행하였다. 또한, 다양한 운동경험과 관련한 피험자의 숙련도가 퍼팅의 분단적 연습과 무작위 연습에 어떤 영향을 미치는지 고찰하여보고자 하였다. 그러므로 본 연구의 목적은 골프의 퍼팅수행에 무작위 연습이 학습효과가 있는지와 피험자의 숙련도가 다양한 연습에 미치는 영향을 검증하는데 있다. 본 연구의 대상은 32명의 피험자를 다음과 같은 네 개의 실험집단에 무작위로 배정하여 실시하였다; 1) 분단적 연습의 숙련자 집단, 2) 분단적 연습의 초보자 집단, 3) 무작위 연습의 숙련자 집단, 4) 무작위 연습의 초보자 집단, 종속변인에는 항상오차, 절대오차, 그리고 가변오차가 사용되었다. 모든 피험자는 3개의 분단으로 나뉜 54회의 연습과 6회의 파지검사와 전이검사를 수행하였다. 연구 디자인은 2(연습방법) X 2(숙련정도) X 3(분단 횟수)이고 마지막 요인에 반복설계된분산분석을 실시하였다. 파지단계와 전이단계는 2(연습방법) X 2(숙련정도)의 디자인으로 분산분석을 실시하였다. 결과는 무작위 연습의 피험자가 연습의 단계에는 낮은 수행을 보였지만 파지검사에서는 높은 수행을 보여 맥락간섭의 효과가 골프의 퍼팅 연습에 적용될 수 있음을 보여주었다. 또한, 숙련자 집단이 초보자 집단에 비하여 모든 단계(연습, 파지, 전이)의 수행에서 더 정확하고 일관성 있는 결과를 보여 숙련자의 효과적인 적응성을 보였지만 연습방법과의 상호관계는 나타나지 않았다. 결론적으로 본 연구의 결과는 퍼팅의 과제에서 무작위 연습의 효과를 입증하였으며 이 결과는 골프의 퍼팅을 연습하는 과정에서 무작위 연습의 방법이 활용되어야 함을 제언하고 있다.