We confirm whether Zr powders can restrain a rapid nitrification reaction and offer a stable oxidation reaction according to temperatures in nitrogen gas purification. A pellet-type, porous Zr getter is prepared (diameter: 10 and thickness: 3 mm) using Zr powder with an average particle size of 45 μm. While maintaining the whole system, the Zr getter reaction is confirmed with an increase in temperature from 150 to 550 oC at increments of 100 oC under 99.999 % purity nitrogen atmosphere comprising of 10 ppm of impurity. Surface color, pore size, stabilized layer, and phase change are confirmed with optical microscopy, SEM-EDS, Micro-Raman, and X-ray diffraction (XRD) according to the Zr getter temperature. The surface color of the Zr getter changes from metallic silver to dark gray as temperature increases. In the EDS results, the nitrogen component is not observed, and oxygen content increases from each surface at elevated temperatures. The Raman and XRD results show the oxidation layer as a result of 350 oC annealing. Therefore, the Zr getter can be applied as a nitrogen getter under 5-nine purity nitrogen atmosphere after appropriate oxidized pre-stabilization process to prevent rapid nitrification reaction.

우간다에서 쌀은 식량, 농가소득 및 안보를 위한 전략적 작물로 목화, 커피, 옥수수에 이어 우간다의 농업 전략 계획 (ASSP)에서 우선순위12개 작물 중 4번째로 선정될 정도로 매우 중요한 작물이다. 쌀은 생산 측면에서 옥수수에 이어 두 번째로 중요한 곡물이다. 최근 우간다에서는 쌀 소비가 빠르게 증가함과 동시에 매년 쌀 수입 또한 비례적으로 빠르게 증가하고 있다. 쌀의 소비 증가는 우간다 쌀 생산량의 90%를 차지하는 소규모 재배 농민들에게 엄청난 경제적 기회를 제공하고 있는데 이는 쌀은 다른 곡물에 비해 상대적으로 훨씬 높은 금액으로 판매되고 이익 또한 높기 때문에 현금 작물로서 벼 재배 면적이 빠르게 증가하고 있는 실정이다. 그러나 벼 생산성은 여전히 낮은 수준인데, 이는 주로 수확량이 적은 쌀 품종의 사용, 개선 된 품종의 종자에 대한 농부의 접근 제한, 낙후된 재배 기술, 비료 및 농약 사용이 매우 저조하기 때문이다. 우간다의 쌀 재배 현황과 여건에 대하여 조사한 바는 아래와 같이 정리할 수 있다. 1. 쌀 생산을 위한 기후적 여건: 연평균 강수량은 1,180 mm 정도이고 연평균 기온은18도에서 35도 사이로 벼 재배에 좋은 기후적 여건이다. 2. 주요 재배 지역: 우간다에는 3곳의 주요 벼 재배 중심지역이 있다. 동쪽 지역은 주로 관개시설과 강수에 의존하는 밭 벼를 재배하고 있으며, 북쪽과 중서부 지역은 논벼를 주로 재배하고 있다. 우간다 쌀 생산량의 90%를 차지하는 소규모 재배 농민들은 주로 위의 3지역에서 벼를 생산하고 있다. 3. 벼 생산성에 영향을 미치는 요소들: 제한적 관개시설과 기계화, 그리고 양질의 종자 부족과 낮은 수준의 농업기술 등이 낮은 생산성의 주요 요소들이며, 수확 후 관리 기술과 저 장 시설 부족, 충분하지 못한 재정적 지원 그리고 병해충 등의 요소들이 있다. 4. 주요 벼 품종: 우간다 현지에서 주로 재배되는 벼 품종은 9종으로서 다음과 같다. Namche, Komboka, Kaiso, Wita 9, Basmat 370, IR 64, Supa, Buyu 및 NERICA 품종이다. 5. 농촌진흥청 한-아프리카 농식품 기술협력 협의(KAFACI)를 통해 높은 생산성과 질병 저항성을 목적으로 개발 후 육종 된 두 한국 품종(KAF-172-67과 KAF-304-287)은 우간다에서 등록절차가 진행될 예정이다.

Various biometric and geometric measures were used to discriminate between the morphologically similar river puffer, Takifugu obscurus, tiger puffer, T. rubripes, their hybrids, and their triploid hybrids. The hybrids and triploid hybrids had greater anal fin width, nostril width, and snout length than the parental species (p<0.05). However, they had less caudal peduncle depth, inter-orbital width, head length, and head width (p<0.05). The morphometric and meristic characteristics of the hybrids and triploid hybrids were either intermediate between the parental species or more similar to those of one parental species. However, the external morphology of the hybrids and triploid hybrids was predominantly maternal. The triploid hybrids had asymmetry in the fin rays and gill raker numbers. This study identified phenotypic characteristics by distinguishing the morphological variables of river puffer, tiger puffer, their hybrids, and their triploid hybrids.

The content of harmful materials was investigated for coffee beans sold in Daejeon. Total 79 samples were analysed and 213 residual pesticides and 2 heavy metals were analysed simultaneously by GC-MS/MS, GC-NPD, GC-ECD, LC-MS/MS and ICP-MS. The instrumental method was validated with limit of detection (LOD), limit of quantification (LOQ), the linearity of standard curves. LOD of the residual pesticides was between 0.0003 to 0.0021 mg/kg, LOQ of the residual pesticides was between 0.0008 to 0.0064 mg/kg. LOD of the heavy metals was between 0.0077 to 0.0079 μg/kg, LOQ of the heavy metals was between 0.0233 to 0.0239 μg/kg. The linearity correlation coefficient for the calibration curve was between 0.9929 to 0.9999 and the recovery rate was between 95.4% to 106.1%. According to the monitoring of residual pesticides and heavy metals, no pesticide was detected in all coffee bean samples. 88.6% (70 samples) of analysed total 79 coffee beans contained at least 1 heavy metal but there was no sample which exceeded the maximum residual limit. Risk assessment was also carried out based on the content of heavy metals detected in coffee beans. The carcinogenic risk assessment to heavy metals showed that all cancer-risk (CR) values were below 10–6 and it meant that the CR due to heavy metals intake was evaluated as safe. The non-carcinogenic risk assessment to heavy metals showed that all hazard index (HI) were below 1, which was considered acceptable at the current level of exposure. The %PTWI values of lead and cadmium for 55 roasted coffee bean samples were 0.09% and 0.04% respectively, compared with the reference values. This results indicate that there is almost no health risk from heavy metal intake through the consumption of coffee beans in circulation in Daejeon.

Spermatogonial stem cells are self-renewal and differentiate into sperm in post-pubertal mammals. There exists a balance between the self-renewal and differentiation in the testes. Spermatogonial stem cells make up only 0.03% of testicular cells in adult mice. These cells maintain sperm production by differentiating after puberty. Therefore, analyzing the expression of genes associated with spermatogenesis is critical for understanding differentiation. The present study aimed to establish the postnatal period of cells in relation to spermatogenesis. To study the expression of differentiated and undifferentiated marker genes in enriched spermatogonial stem cells, in vitro culture was performed and cells from pup (6–8-day-old) and adult (4-months-old) testicular tissues were isolated. As a result, undifferentiated genes, Pax7, Plzf, GFRa1, Etv5 and Bcl6b , were highly increased in cultured spermaotogonial stem cells compared with pup and adult testicular cells. On the other hands, differentiated gene, c-kit was highly increased in adult testicular cells, Also Stra8 gene was highly increased in pup and adult testicular cells. This study provides a better understanding of spermatogenesis-associated gene expression during postnatal periods.

Several factors, including genetic and environmental insults, impede protein folding and secretion in the endoplasmic reticulum (ER). Accumulation of unfolded or mis-folded protein in the ER manifests as ER stress. To cope with this morbid condition of the ER, recent data has suggested that the intracellular event of an unfolded protein response plays a critical role in managing the secretory load and maintaining proteostasis in the ER. Tauroursodeoxycholic acid (TUDCA) is a chemical chaperone and hydrophilic bile acid that is known to inhibit apoptosis by attenuating ER stress. Numerous studies have revealed that TUDCA affects hepatic diseases, obesity, and inflammatory illnesses. Recently, molecular regulation of ER stress in tooth development, especially during the secretory stage, has been studied. Therefore, in this study, we examined the developmental role of ER stress regulation in tooth morphogenesis using in vitro organ cultivation methods with a chemical chaperone treatment, TUDCA. Altered cellular events including proliferation, apoptosis, and dentinogenesis were examined using immunostaining and terminal deoxynucleotidyl transferase dUTP nick end labeling assay. In addition, altered localization patterns of the formation of hard tissue matrices related to molecules, including amelogenin and nestin, were examined to assess their morphological changes. Based on our findings, modulating the role of the chemical chaperone TUDCA in tooth morphogenesis, especially through the modulation of cellular proliferation and apoptosis, could be applied as a supporting data for tooth regeneration for future studies.