• 대한한의학회지
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• 제17권2호
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• pp.296-302
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• 1996

Pericarpium Citri Nobilis Viride, a traditional herb medicine, has been used in Korea and China for many centuries as a treatment for respiratory disease. The purpose of the present study was to determine the effect of Pericarpium Citri Nobilis Viride on histamine-induced tracheal smooth muscle contraction in rats. Guinea pigs(500g , female) were killed by $CO_2$ exposure and a segment (8-10mm) of the thoracic trachea from each guinea pig was cut into equal segments and mounted 'in pairs' in a tissue bath. Contractile force was measured with force displacement transducers under 0.5g loading tension. The dose of histamine which evoked 50% of maximal response $(ED_{50})$ was obtained from cumulative dose response curves for histamine $(10^{-7}-10^{-4}M)$. Contractions evoked by histamine ($ED_{50}$) were inhibited significantly by Pericarpium Citri Nobilis Viride. The mean percent inhibition was 53.7% (P<0.05) after 1.5mg／ml Pericarpium Citri Nobilis Viride, and 87.7% (P<0.01) after 5.0mg／ml Pericarpium Citri Nobilis Viride. Propranolol $(10^{-7}M)$ slightly but significantly attenuated the inhibitory effects of Pericarpium Citri Nobilis Viride. Following treatment with propranolol the mean present inhibition caused by 1.5 and 5.0mg／ml Pericarpium Citri Nobilis Viride. Indomethacin and methylene blue $(10^{-7}M)$ did not significantly alter the inhibitory effect of Pericarpium Citri Nobilis Viride These results indicate that Pericarpium Citri Nobilis Viride can relax histamine-induced contraction of guinea pig tracheal smooth muscle, and that this inhibition involves in part symphathetic nerve system.

• 한국응용과학기술학회지
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• 제20권4호
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• pp.289-295
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• 2003

Synthesis gas is produced commercially by a steam reforming process. However, the process is highly endothermic and energy intensive. Thus, this study was conducted to produce synthesis gas by the partial oxidation of methane to cut down the energy cost. Supported Ni catalysts were prepared by the impregnation method. To examine the activity of the catalysts, a differential fixed bed reactor was used, and the reaction was carried out at $750{\sim}850^{\circ}C$ and 1 atm. The fresh and used catalysts were characterized by XRD, XPS, TGA and AAS. The highest catalytic activity was obtained with the 13wt% Ni/MgO catalyst, with which methane conversion was 81%, and $H_2$ and CO selectivities were 94% and 93%, respectively. 13wt% Ni/MgO catalyst showed the best $MgNiO_2$ solid solution state, which can explain the highest catalytic activity of the 13wt% Ni/MgO catalyst.

• Applied Biological Chemistry
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• 제42권2호
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• pp.128-133
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• 1999

참치내장 중 유문수 조직에 내재되어 있는 단백질 분해효소를 부분정제하여 추출한 후 민태 frame 단백질의 효소적 가수분해에 이용하였으며, 제조된 가수분해물을 한외여과막을 이용하여 분자량 크기에 따라 분획한 후 기능성을 개선시킬 목적으로 cyclic sodium trimetaphosphate를 이용하여 인산화 민태 frame 단백질 가수분해 물을 제조하고, 용해도, 유화성 및 포말성 등과 같은 기능성을 검토하였다. 1 가수분해물의 기능성 개선을 목적으로 가수분해물에 STMP를 처리하여 인산화된 가수분해물을 제조하였으며, IR 스펙트럼으로 인산화를 확인한 결과, $1300\;cm^{-1}$에서 P=O의 흡수띠를, $1000{\sim}1100\;^{-1}$에서 P-O-C와 alkyl group에 결합된 P-O-C의 흡수띠를 확인하였다. 2. 민태 frame 단백질 가수분해물을 인산화시킴으로써 용해도는 물론 유화성 및 유화 안정성 그리고 포말 안정성 등 기능성의 개선에 크게 효과를 나타내었다. 특히 분자량이 가장 큰 획분인 P-30K 가수분해물은 모든 기능성 부분에서 좋은 결과를 나타내어 미이용자원으로부터 기능성이 부여된 새로운 가치의 물질로서 활용이 기대된다.

• Journal of Biosystems Engineering
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• 제42권2호
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• pp.80-85
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• 2017

Purpose: In this study, we attempted to analyze, by using a high-speed camera, the cutting shape as a function of cutting speed and feed rate. We compared the differences in cutting shape between domestic and foreign combines. Methods: Experiments were performed using plastic straws, and the results of two combine cutting blades, one from the Daedong Industry and one from Kuboda, were compared. The quality and performances of cutting were measured at three cutting positions: center and 68 cm to the left and right of the center. The feed rates were 0.6 m/s, 1.1 m/s, 1.6 m/s, and the cutting speeds were 600 RPM, 990 RPM, 1,380 RPM. For each speed, the cutting shape was measured three times, and the entire procedure was also repeated three times. Results: In the experiments, the domestic cutting blade achieved better results than the Japanese cutting blade. These results were obtained by studying the combination of feed rate and cutting speed, with the domestic combine attaining approximately 80% performance of the Japanese combine. We believe that additional data analysis is required, obtained from field experiments. Conclusions: The domestic cutting knives achieved better results than the Japanese cutting knives. These results are estimated from experiments conducted with different feed rates and cutting speeds; an in-depth analysis will require experiments in the real field with actual combines and a combination of multiple variables. Repeating the investigation on the length differences, broken and cut angle with various combinations of feed rate and cutting speed, will surely help to find the optimal cutting speed.

• 대한한의학방제학회지
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• 제10권2호
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• pp.143-158
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• 2002

The purpose of the present study is to determine the effect of Jakyakgamchotang on histamine or acetylcholine induced tracheal smooth muscle contraction in rats and guinea pigs. Guinea pig(500g, male) and Sprague Dawley rats(250g, male) were killed by $CO_2$ exposure and a segment (4-5mm) of the thoracic trachea from each rat and guinea pig was cut into equal segments and mounted 'in pairs' in a tissue bath. Contractile force was measured with force displacement transducers under 0.5g loading tension. The dose of histamine(His) which evoked 50% of maximal response($ED_{50}$) was obtained from cumulative dose response curves for histamine($10^{-7}{\sim}10^{-4}M$). Contractions evoked by His($ED_{50}$) were inhibited significantly by Jakyakgamchotang. In guinea pig tracheal smooth muscle, the mean percent inhibition of histamine induced contraction was 90.8% (p〈0.001) after $100{\mu}l/ml$ Jakyakgamchotang. In rat tracheal smooth muscle, the mean percent inhibition of acetylcholine induced contraction was 22.1% (p〈0.05) after $100{\mu}l/ml$ Jakyakgamchotang. Propranolol indomethacin and methylene blue($10^{-7}M$) slightly but significantly attenuated the inhibitory effects of Jakyakgamchotang. These results indicate that Jakyakgamchotang can relax histamine or acetylcholine induced contraction of guinea pig and rat tracheal smooth muscle.

• Korean Journal of Acupuncture
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• 제17권1호
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• pp.67-73
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• 2000

The purpose of the present study is to determine the effect of Radix Stemonae on histamine induced tracheal smooth muscle contraction in guinea pigs. Guinea pig(500g, male) were killed by $CO_2$ exposure and a segment (8-10mm) of the thoracic trachea from guinea pig was cut into equal segments and mounted 'in pairs' in a tissue bath. Contractile force was measured with force displacement transducers under 0.5g loading tension. The dose of histamine (His) which evoked 50% of maximal response ($ED_{50}$) was obtained from cumulative dose response curves for histamine ($10^{-7}∼10^{-4}M$). Contractions evoked by His ($ED_{50}$) were inhibited significantly by Radix Stemonae. In guinea pig tracheal smooth muscle, the mean percent inhibition of histamine induced contraction was 87.4% (p<0.01) after $100{\mu}l/ml$ Radix Stemonae. Following treatment with propranolol, the mean percent inhibition caused by $100{\mu}l/ml$ Radix Stemonae fell to 16.2% in guinea pig induced by histamine contraction. Indomethacin and methylene blue($10^{-7}M$) did not significantly alter the inhibitory effect of Radix Stemonae. These results indicate that Radix Stemonae can relax histamine induced contraction of guinea pig tracheal smooth muscle, and that this inhibition involves sympathetic effects.

• 한국운동역학회지
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• 제26권4호
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• pp.333-341
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• 2016

Objective: The purpose of this study was to assess the consistency of the gliding and push-off motion for single leg skating from the first to fourteenth steps. We hypothesized that: 1) there would be no difference in stroke trajectory, step rate, and cycle rate between the left and right steps of gliding; and 2) there would be a difference in the resultant velocity of toe push-off and the horizontal velocity of the center of mass after six step push-offs. Method: The study included five male 500-m speed skaters (mean height, $1.80{\pm}0.02m$; mean weight, $76.8{\pm}3.96kg$; record, $35.83{\pm}0.30sec$; 100-m record, <9.97 sec). Data were collected from the first to fourteenth steps (40 m) and recorded using five digital JVC GR-HD1KR video cameras (Victor Co., Japan) operating at a sampling frequency of 60 fields/sec and shutter speed of 1/500 sec. For each film frame, the joint positions were digitized using the KWON3D motion analyzer. Position data were filtered with low-pass Butterworth $4^{th}$ order at the cut-off frequency of 7.4 Hz. Results: The right toe of the skating trajectories at $2^{nd}$, $5^{th}$, and $7^{th}$ strokes differed from those of the left toe. The angles of the right and left knee demonstrated unbalanced patterns from the flexion and extension legs. The step and cycle rates of the right and left leg differed from the start until 20 m. The resultant velocities of the toe at the push-off phase and of the body mass center diverged before the six push-offs. Conclusion: This study's findings indicate that the toe of skating trajectory on left and right sliding after push-off should maintain a symmetrical trajectory. The resultant velocity of toe push-off and horizontal velocity from the center of body need to be separated after about six step push-offs.

• 한국정보전자통신기술학회논문지
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• 제15권5호
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• pp.387-395
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• 2022

PDRN(Polydeoxyribonucleotide)은 조직재생 활성물질로 손상된 세포 및 조직의 자가 재생을 촉진하는 DNA 유래의 중합물질이다. PDRN은 DNA를 다양한 물리적 또는 화학적 방법으로 작은 크기로 절단한 DNA 조각으로 체내 투여시 조직세포 표면의 adenosine A2A receptor 수용체를 자극하여 세포 재생을 촉진하며 상처를 빠르게 회복시키고, 통증도 감소시키는 효과가 있다. 보통 어류의 정소나 정액으로부터 PDRN 추출을 하지만 본 연구에서는 다양한 식물에서 PDRN 추출 실험을 진행하였다. 실험 결과, 7종의 식물에서 PDRN 수율과 순수도는 단위 식물 중량 당 쑥갓이 가장 높았고, 브로콜리가 그 다음으로 우수했다. 이 두 식물의 PDRN을 대상으로 시험관에서 wound healing assay를 진행하여 PDRN의 효능을 분석한 결과, ㎍/ml 수준의 쑥갓과 브로콜리의 PDRN가 유의하게 wound healing 활성이 높음을 확인하였다. 본 연구의 결과는 이들 식물 유래 PDRN이 연어와 같은 어류 유래의 PDRN의 대체제로 사용할 수 있음을 의미한다.

• 한국컴퓨터정보학회논문지
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• 제27권11호
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• pp.115-121
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• 2022

표면실장기술(SMT)에서 솔더 크림을 바르는 장비인 스크린 프린터는 패드가 작아지면서 도포 불량이 많이 발생한다. 이를 해결하기 위해 최근에는 젯 프린터를 사용하고 있다. 그런데 젯 프린터 헤드에 적용하는 밸브의 끝단 노즐을 깨끗하게 청소하지 않으면 과납이나 오도포가 발생한다. 이를 방지하기 위해서는 노즐을 주기적으로 청소해줘야 한다. 본 논문에서는 젯 프린터의 안정적인 솔더 크림 도포를 위하여 기존 기술보다 더욱 안정적으로 청소하는 방법을 제시하였다. 이 방법은 35mm 폭의 무진천을 재단하여 롤 형태로 감아 놓고, 반대쪽에 DC 기어드 모터로 회전시켜 닦는다. 그 결과 약 2,000회 도팅 주기로 청소를 했을 때 노즐 표면에 솔더 페이스트가 남지 않고 잘 닦이는 것을 확인하였다.

• ALGAE
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• 제38권2호
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• pp.127-139
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• 2023

Cryptic stages of diverse macroalgae present in natural substrata, "the bank of microscopic forms", were isolated into clonal cultures and identified based on both morphological characteristics and DNA barcoding. Approximately 120 clonal isolates from 308 natural substratum samples were collected from the entire coastline of Kuwait. Amongst these isolates, 77 (64%) were identified through DNA barcoding using the nuclear ribosomal small subunit, RuBisCO spacer (ITS2, tufa, rbcL, psaA, and psbA) and sequencing. Twenty-six isolates (34%) were identified in the division Chlorophyta, 18 (23%) as Phaeophyceae, and 33 (43%) as Rhodophyta. For all DNA sequences in this study, species-level cut off applied was ≥98% homology which depend entirely on the markers used. Three putative new records of Chlorophyta new for the Arabian Gulf were made: Cladophora laetevirens (Dillwyn) Kützing, Ulva torta (Mertens) Trevisan and Ulvella leptochaete (Huber) R. Nielsen, C. J. O'Kelly & B. Wysor in Nielsen, while Cladophora gracilis Kützing and Ulva ohnoi M. Hiraoka & S. Shimada are new records for Kuwait. For Phaeophyceae, Ectocarpus subulatus Kützing and Elachista stellaris Areschoug were new records for the Gulf and Kuwait. In the Rhodophyta, Acrochaetium secundatum (Lyngbye) Nägeli in Nägeli & Cramer, Ceramium affine Setchell & N. L. Gardner, Gelidium pusillum var. pakistanicum Afaq-Husain & Shameel and Dasya caraibica Børgesen are new records for the Gulf and Kuwait, while the red alga Stylonema alsidii (Zanardini) K. Drew is a new record for Kuwait. Several isolates identified corresponded to genera not previously reported in Kuwait and / or the Arabian Gulf, such as Porphyrostromium Trevisan, a new genus from the Bangiales, and two unidentified species for the Planophilaceae Škaloud & Leliaert. The isolates cultivated from substrata enhance understanding of the marine macroalgal diversity in the region and confirmed that the Germling Emergence Method is suitable for determining the actual diversity of a given study area through isolation from cryptic life-history phases.