• 한국식물병리학회:학술대회논문집
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• 한국식물병리학회 1995년도 Proceedings of special lectures on Molecular Biological Approaches to Plant Disease National Agricultural Science and Technology Institute Suwon, Korea
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• pp.55-75
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• 1995

Induction of HMG-Co A reductase (HMGR) is essential for the biosynthesis of sesquiterpenoid phytoalexins and steroid derivatives in Solanaceous plants following wounding and pathogen infection. To better understand this complex step in stress-responsive isoprenoid synthesis, three classes of cDNAs for HMGR (hmg1, hmg2, and hmg3) were isolated from a potato tuber library. The potato cDNAs had extensive homology in open reading frames but had low homology in the 3'-untranslated regions. RNA gel blot analysis using gene-specific probes revealed that hmg1 is induced by wounding but wound induction is strongly suppressed by arachidonic acid or by inoculation with Phytophthora infestants. In contrast, hmg2 and hmg3 are slightly induced by wounding and strongly enhanced by arachidonic acid or inoculation. The induction and suppression of HMGR genes parallel the suppression of steroid and stimulation of sesquiterpenoid accumulations observed in earlier investigations. Treatment of the tuber disks with a low concentration of methyl-jasmonate doubled the wound induced accumulation of hmg1 transcripts and steroid-glycoalkaloid accumulation, but did not affect the abundance of transcripts for hmg2 or hmg3 nor induce phytoalexins. High concentration of methyl-jasmonate suppressed hmg1 mRNA and steroid-glycoalkaloid accumulation, induced hmg3 mRNA, and did not elicit phytoalexins. Lipoxygenase inhibitors suppressed the accumulation of of hmg1 transcripts and steroid-glycoalkaloids, which were restored by exogeneous methyl-jasmonate. Methyl-jasmonate applied together with arachidonic acid enhanced the elicitor induced accumulation of sesquiterpenes and sustained steroid-glycoalkaloid levels with transcript levels for the various HMGR mRNAs equal to or greater than wound-only treatment. These results domonstrate that the consequences of wound- and pathogen-responses of plants are different at the levels of gene expression and associated secondary metabolism.

• Environmental Engineering Research
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• 제19권2호
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• pp.145-149
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• 2014

Arsenic (As) is one of the heavy metals which causes acute bio-toxicity even at low concentration and has disastrous effect on environment. In some countries, As contamination has become alarming and increasing day by day as consequences of unsustainable management practices. Many existing physical, chemical and biological processes for As removal from water system are not feasible due to techno-economic limitations. The present study highlights the scope of biological strategy for As removal through phytoextraction. Arsenic uptake and accumulation in the biomass of three plant species and their As tolerance abilities have been investigated to develop an efficient phytoextraction system in combination of these plant species. Three non-crop plant species, Pteris vittata; Mimosa pudica, and Eichhornia crassipus were treated with 0-200 mg/L As in liquid nutrient solution for 14 days. P. vittata accumulated total 9,082.2 mg (8,223 mg in fronds) As/kg biomass and Eichhornia total 6,969 mg (4,517 mg in fronds)/kg biomass at 200 mg/L As concentration, respectively. Bioaccumulation factor (BF) and translocation factor (TF) were estimated to differentiate between excluders, accumulators and accumulation in above ground biomass. Pteris and Eichhornia have highest BF (67 and 17) and TF (64 and 3), respectively. In contrast, Mimosa accumulated up to 174 mg As/kg plant biomass which is low in comparison with other two plants, and both BF and TF were ${\leq}1$. This study reveals that Pteris and Eichhornia are As hyperaccumulator, and potential candidates for As removal from water system.

• 한국수소및신에너지학회논문집
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• 제18권4호
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• pp.365-373
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• 2007

We optimized the compositions of electrolyte and additives for anode in Ni-MH battery to improve the electrode characteristics at ambient and low temperatures using response surface method(RSM). Among various additives for anode, PTFE exhibited the greatest influence on the discharge capacity of the anode. Through response optimization process, we found the optimum composition of the additives to exhibit the greatest discharge capacity. When the amount of additives was too small, the anode was degraded with time due to the low binding strength among alloy powders and the resultant separation of powders from the current collector. In contrast, the addition of large amount of the additives increased in the resistance of the electrode. In addition, the discharge capacity of the anode at $-18^{\circ}C$ increased with decreasing the concentration of KOH, NaOH and LiOH in design range of electrolyte. The resistance and viscosity of electrolyte appear to affect the discharge capacity of the anode at low temperature.

• Childhood Kidney Diseases
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• 제28권1호
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• pp.27-34
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• 2024

Purpose: The ability to concentrate urine becomes an important index in determining nocturnal enuresis (NE) treatment. The aim of our study was to investigate first-morning urine osmolality (Uosm) changes at the end of treatment compared to before treatment in children with NE. Methods: A total of 71 children with NE were divided into two groups according to the level of first-morning Uosm before treatment: high group (≥800 mOsm/kg) and low group (<800 mOsm/kg). Baseline parameters were obtained from uroflowmetry, frequency volume charts for at least 2 days, and a questionnaire for lower urinary tract symptoms. All patients were basically treated with standard urotherapy and medication. The first-morning Uosm was measured twice, before treatment and at the end of treatment. Results: The response rate was higher in the low group after 3 months of treatment than in the high group (P=0.041). However, there was no difference between the two groups at the end of the treatment. In the high group, the first-morning Uosm at the end of treatment did not show a significant change compared to before treatment. In contrast, the first-morning Uosm increased in the low group at the end of treatment (P<0.001). However, it was still lower than that of the high group (P=0.007). Conclusions: The ability to concentrate nocturnal urine improved at the end of treatment compared to before treatment in the low Uosm NE children. In addition, NE improved faster in the low Uosm group before treatment than in the high group.

• 생명과학회지
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• 제12권6호
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• pp.669-675
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• 2002

저가 수산물의 부가가치를 높이고 소비를 촉진시키기 위하여 이들을 이용한 인스턴트 생선회를 제조하여 산업화할 필요성이 대두되고 있다. 인스턴트 생선회를 제조할 때 생선회를 원인식으로 하는 식중독 세균의 제어가 필수적이므로 생선회 소스의 원료인 유기산을 대상으로 생선회 식중독 유발 세균의 생존에 미치는 영향을 실험하였다. 식초(총산도 6.0-7.0%)와 젖산(총산도 8.0-9.0%)은 낮은 농도에서도 Vibrio속에 대한 항균활성이 강하게 나타났으며 Vibrio vulnificus(V. vulnificus), V. cholerae non-O1, V. parahaemolyticus, V. mimicus 순이었고, Salmonella typhimurium(S. typhimurium)과 Escherichia coli O157:H7(E. coli O157:H7)은 비교적 높은 농도에서 항균활성이 약하게 나타났다. 최소생육저해농도(MIC)는 식초의 경우 V. vulnificus 16$\mu\textrm{g}$/$m\ell$, V. cholerae non-O1 18$\mu\textrm{g}$/$m\ell$, V. mimicus 16$\mu\textrm{g}$/$m\ell$, V. parahaemolyticus 12$\mu\textrm{g}$/$m\ell$, S. typhimurium 26$\mu\textrm{g}$/$m\ell$, E. coli O157:H7 20$\mu\textrm{g}$/$m\ell$를 나타내었고, 젖산의 경우 V. vulnificus 20$\mu\textrm{g}$/$m\ell$, V. cholerae non-O1 25$\mu\textrm{g}$/$m\ell$, V. mimicus 25$\mu\textrm{g}$/$m\ell$, V. parahaemolyticus 25$\mu\textrm{g}$/$m\ell$, S. typhimurium 40$\mu\textrm{g}$/$m\ell$, E. coli O157:H7 35$\mu\textrm{g}$/$m\ell$를 나타내었다. 순간 살균력 (10초)은 식초의 경우 V. vulnificus 8%, V. cholerae non-O1 14%, V. mimicus 10%, V. parahaemolyticus 4%, E. coli O157:H7 48%에서 증식되지 않았지만 S. typhimurium은 50%에서도 집락이 검출되었다. 젖산의 경우 V. vulnificus 2%, V. cholerae non-O1 3%, V. mimicus 4%, V. parahaemolyticus 3%, S. typhimurium 14%, E. coli O157:H7 17%에서 증식되지 않았다. 식초와 젖산은 낮은 농도에서 생선회 식중독 유발에 주 원인균이 되는 Vibrio 속의 생육을 억제하였고, S. typhimurium과 E. coli O157:H7의 생육은 비교적 약하게 나타났다.

• 한국의류학회지
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• 제32권6호
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• pp.991-998
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• 2008

본 연구는 상변화물질의 농도가 의복내 공기충의 온도변화에 미치는 영향을 연구하고자 하였다. 상변화물질로는 노나데칸을 사용하였으며 농도는 아크릴 바인더 대비 10%, 20%, 30%로 조절하여 면직물에 코팅처리하였다. 동적 열전달 측정장치인 Human-Clothing-Environment Simulator을 사용하여 고온에서 저온 이동시 다시 고온이동시의 의복내 온도변화를 측정하였다. 외부 환경온도는 고온은 34도, 저온은 5도와 10도를 하였으며 먼저 34도에서 한시간 동안 컨디셔닝한 후에 5도 또는 10도에 30분 동안 노출시켜 의복내 온도변화를 측정하였고 다시 34도에 노출시켜 30분동안 의복내 공기층에서의 상변화물질의 열적거동을 살펴보았다. 그 결과 상변화물질처리된 직물로 이루어진 의복내 공기층은 고온에서 저온이동시 상변화물질의 발열효과로 인해 미처리 직물보다 높은 온도를 나타내었으며, 저온에서 고온이동시에는 흡열효과로 인해 미처리 직물보다 온도상승이 느리게 나타났다. 농도가 증가할수록 상변화물질에 의한 발열효과는 증가하는 것으로 나타났으며 흡열효과의 경우에는 20%에서 큰 변화를 갖는 것으로 나타났다. 농도변화에 따른 미처리와 처리직물 사이의 차이를 보면, 10%에서 20% 증가시에 나타난 차이가 20%에서 30% 농도변화시에 나타난 차이보다 크게 나타났다. PCM 처리된 모든 직물들이 상변화를 겪는 것은 아니었으며 직물층에 따라 상변화를 하였고 최외곽층의 경우에는 상변화물질에 의한 흡열발열현상외에도 외부로의 열손실을 겪기 때문에 이에 대한고찰이 있어야하는 것을 알 수 있었다.

• 지질공학
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• 제33권4호
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• pp.587-598
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• 2023

지하수의 라돈 함량이 높은 것으로 알려진 연구지역 지하수의 라돈 함량분포와 시기별 함량변화를 파악하기 위하여 10개 지하수공과 1개 하천수를 대상으로 2개월 간격으로 12회에 걸쳐서 라돈 함량 분석과 DTW(Depth to water table)를 측정하였다. 연구지역 중앙에 위치한 지하수의 라돈 함량은 37.0~2,675.2 Bq/L로 높았으나 연구지역 외곽에서는 10.6~37.9 Bq/L로 낮았다. 연구지역 중앙에 위치한 지하수의 라돈 함량이 높은 것은 옥천층군을 관입한 화강반암과 이에 따른 파쇄대가 발달하였기 때문으로 해석된다. 연구지역 외곽에 위치한 지하수의 라돈 함량이 낮은 것은 화강반암 관입부로부터 떨어진 옥천층군에 위치하고 있기 때문으로 해석된다. 연구지역 중앙에 위치한 지하수의 라돈 함량 변화가 크게 일어나는 것은 연구지역 중앙이 저지대일 뿐만 아니라 계절별 지하수위 변화가 크게 일어나며 이로 인해 천부의 저 함량 라돈 지하수가 고 함량 라돈 지하수에 유입되기 때문으로 보인다.

• 멤브레인
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• 제19권1호
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• pp.63-71
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• 2009

본 연구에서는 연료전지용 전해질 복합체용 지지체 막을 저가의 우수한 기계적 열적 안정성을 가지는 Polysulfone으로 상전이 법을 이용하여 제조하였다. 제조된 막을 이용하여 농도변화와 노출시간의 변화에 따른 열 수축율, 통기도, 모폴로지, 기계적 물성 및 다공도를 측정하였다. 모폴로지를 조절하기 위해 공기 중 노출 시간과 고분자 농도가 제어되었으며, 제조된 막은 고분자 농도 변화에 관계없이 모두 스폰지 구조를 나타내었다. 고분자의 농도가 증가함에 따라 기계적 열적 안정성은 증가하였지만, 다공도는 감소하는 결과를 보였다. 실험결과 20 wt%의 PSf 고분자 용액을 사용하여 2분의 노출시간을 두고 제조된 고분자 막에서 연료전지용 복합막으로 사용되기 위한 충분한 다공도(80%)와 기계적(tensile : 1.3 MPa), 열적(MD, TD shrinkgage < 1%) 안정성을 나타내었다.

• Ocean and Polar Research
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• 제33권4호
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• pp.457-472
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• 2011

To elucidate the trophic role of heterotrophic nano- and microplankton (HNMP), we investigated their biomass, community structure, and herbivory in three different water masses, namely, south of Polar Front (SPF), Polar Front Zone (PFZ), the Sub-Antarcitc Front (SAF) in the Drake Passage in the Southern Ocean, during the austral summer in 2002. We observed a spatial difference in the relative importance of the dominant HNMP community in these water masses. Ciliates accounted for 34.7% of the total biomass on an average in the SPF where the concentration of chlorophyll-a was low with the dominance of pico- and nanophytoplankton. Moreover, the importance of ciliates declined from the SPF to the SAF. In contrast, heterotrophic dinoflagellates (HDFs) were the most dominant grazers in the PFZ where the concentration of chlorophyll-a was high with the dominance of net phytoplankton. HNMP biomass ranged from 321.9 to 751.4 $mgCm^{-2}$ and was highest in the PFZ and lowest in the SPF. This result implies that the spatial dynamic of HNMP biomass and community was significantly influenced by the composition and concentration of phytoplankton as a food source. On an average, 75.6%, 94.5%, and 78.9% of the phytoplankton production were consumed by HNMP in the SPF, PFZ, and SAF, respectively. The proportion of phytoplankton grazed by HNMP was largely determined by the composition and biomass of HNMP, as well as the composition of phytoplankton. However, the herbivory of HNMP was one of the most important loss processes affecting the biomass and composition of phytoplankton particularly in the PFZ. Our results suggest that the bulk of the photosynthetically fixed carbon was likely reprocessed by HNMP rather than contributing to the vertical flux in Drake Passage during the austral summer in 2002.

• 한국동물학회지
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• 제11권3호
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• pp.85-91
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• 1968

1963年에서 1967年에 걸쳐 서울地區의 人工放射能과 自然放射能을 全放射能의 測定과 放射性核種의 分析을 통하여 硏究하였다. 核分裂生成物의 濃度가 적을때는 \ulcorner은 半減期를 갖는 라듐이나 토리음의 崩壞生成物이 浮游塵의 大部分을 차지하고 있었으며 核分裂生成物에 依한 放射能은 試料 採取후 며칠 지나야 正確히 評價할수 있었다. 7次에 걸친 中共의 核實驗의 結果 두차례의 强放射能이 爆發후 30時間을 前後하여 서울地區에 나타났으며 이들은 1956年에서 1962年 사이에 美國과 蘇聯에서 행한 實驗과 比較할 때 높은 比放射能을 보였으나 持續時間은 아주 짧아서 1週內에 急激히 減少하였다. 이로 보아서 서울地區의 放射能汚染은 中共의 核實驗인 境遇 核實驗의 規模와 實驗高度 및 爆發前後의 氣象條件, 特히 高層對流圈의 제트氣流에 依해서 많은 影響을 받음을 알았다.