• 한국패류학회지
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• 제27권3호
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• pp.181-190
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• 2011

본 연구는 백합과 이매패류인 바지락, Ruditapes philippinarum을 노닐페놀에 노출시켰을 때, 생식 및 조직학적 지표 변화에 대해서 조사하였다. 실험기간은 16주였다. 실험구는 1개의 대조구와 3개의 노닐페놀 노출구인 0.05, 0.1, $0.2 mg\;NP\;L^{-1}$였다. 생식소지수는 암컷의 경우, 대조구보다 노출구에서 더 높았으며, 수컷의 경우, 대조구보다 노출구에서 더 낮았다. 이성생식세포 발현율은 14.56%였으며, 수컷에서의 발현율이 더 높았다. 기관계 가운데 외투막에서 혈림프동의 확장, 내부상피층 자유면에 발달하는 선조연의 탈락과 박리, 점액세포의 변성이 관찰되었다. 아가미에서는 정단섬모와 측면섬모의 부분적 소실, interlamella junction 붕괴, 점액세포의 변성이 확인되었다. 발에서는 상피세포의 증식, 선조연의 소실 및 섬모가 탈락되었다. 지방갈색소 축적은 노닐페놀에 농도 의존적으로 높았다. 본 연구결과 노닐페놀은 바지락의 낮은 생존율과 조직병리학적 변화 및 이성생식세포 발현을 유도하며, 더욱이 생식과 관련하여 estrogenic effector로서 가능성을 확인하였다.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제14권1_2호
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• pp.146-153
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• 1992

In the outpatient clinic, we have many patients who suffer from temporomandibular joint disorders. These vary from MPD syndrome to osteoarthrosis, and many cases have tender spots or areas on the temporomandibular joint region and/or masticatory muscles. Further, they frequently have masticatory muscle pain when opening the jaw. This paper presents the results of our research on the differential diagnosis for tendernesses and pain on opening the jaw in the temporomandibular joint region and the masticatory muscles by joint cavity pumping with local anesthestic. The areas of tenderness and jae-opening paw in 65 patient suffering from temporomandibular joint disorder were examined and recorded before and after anesthetizing the upper joint cavity with 2% lidocaine. Maximum interincisal distance was similarly recorded. The results were as follows : In the area surrounding the upper joint cavity including the lateral pterygoid muscle, the tenderness and jaw-opening pain vanished almost entirely after anesthesia. This was considered a direct infiltrative effect of the local anesthesia. After the anesthesia, 86% of the tendernesses on the sternocleidomastoid muscles, and 66% of those on the posterior belly of the diagstric muscles vanished, while the disappearance rates on the masseter, temporal, and medial pterygoid muscles were 50~60%. Apart from the temporomandibular region, pain on opening the jaw was found on the masseter, temporal, posterior belly of the digastric muscles, and medial pterygoid muscles before anesthesia. The disappearance rates after anesthesia were 90~100% except for the pain of the posterior belly of the digastric muscles, for which the rate was 66%. These results suggest that more than 88% of the tendernesses on the sternocleidomastoid muscle, more than 60% of the tendernesses and jaw-opening pains on the digastric muscle, and more than half of the tendernesses and almost all of the jaw-opening pains in the jaw-closing muscles are referred pains from the temporomandibular joint. The tendernesses that had no change after anesthesia were considered to be derived from spasms of the muscles proper. Generally, maximum interincisal distance increased after anesthesia. The average distance was 34mm before anesthesia, but increased to 41mm after anesthesia. In a few cases, however little or no change was found in those distances. In these cases, pathological changes were found in the joint cavities arthrographically or arthroscopically.

• 한국초지조사료학회지
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• 제34권1호
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• pp.60-67
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• 2014

본 연구는 조사료의 반추위 발효가 진행됨에 따른 볏짚표면에 부착된 섬유소 분해 박테리아의 군집변화와 섬유소 소화율을 비교 관측하기 위하여 볏짚의 in situ 반추 발효를 실시하였다. 그리고 부착 박테리아의 군집 변화를 측정하기 위하여 RT-PCR 기법을 이용하여 F. succinogenes. R. albus와 R. flavefaciens의 군집을 모니터링 하였다. 본 연구를 수행하기 위하여 in situ 볏짚 발효를 0. 2, 4, 8, 12, 24시간 실시하였을 때 반추위내 볏짚의 in situ 분해는 발효 시간이 진행됨에 따라 가속화되어 발효 8~12시간 사이에 최고 분해 속도를 나타내었으나, F. succinogenes, R. flavefaciens과 R. albus는 모두 발효 0~1시간 사이에 볏짚 표면에 부착이 80% 이상 완료되어 이후 발효가 계속 진행되는 동안 일정 수준의 군락을 유지하는 것이 발견되었다. 그리고 반추위내 유입된 조사료의 표면에 초기 부착과정을 관찰하기 위하여 0, 5, 10, 30 및 60분 간격으로 볏짚의 in situ 샘플을 채취하여 조사하였을 때 F. succinogenes, R. flavefaciens 및 R. albus의 군락 모두 볏짚이 반추위 유입 후 5분 내에 상당량의 수가 부착함을 발견하였다. 또한 조사료의 반추위 발효 용이성에 따른 섬유소 분해 박테리아의 부착 정도를 관찰하기 위하여 0, 2, 4 및 8% NaOH를 처리한 볏짚을 12 및 24시간 in situ 배양 볏짚의 소화율과 부착 박테리아의 군집 변화를 관측하였을 때, 볏짚의 NaOH 처리 농도가 높아짐에 따라 in situ 소화율이 증가하였으며, 동시에 부착된 박테리아 군집의 증가 경향이 F. succinogenes, R. flavefaciens 및 R. albus의 3균주 모두 배양 12시간에 나타났으나 배양 24시간에서는 각기 다른 양상을 나타냈다. 따라서 본 연구결과는 반추위내 섬유소 발효과정에서 섬유소 분해 박테리아의 부착은 조사료의 반추위 유입 초기에 반드시 이루어지고, 발효 시간이 진행됨에 따라 조사료 표면에 안정된 군락을 형성하며, 섬유소 분해가 가속화된다는 사실을 보여 주었다.

• Asian-Australasian Journal of Animal Sciences
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• 제19권11호
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• pp.1610-1616
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• 2006

Influence of different levels of corn steep liquor (CSL) on chemical composition of urea treated wheat straw (UTWS), ruminal characteristics, digestion kinetics, nitrogen (N) utilization, and nutrient digestibility by ruminally-cannulated buffalo bulls was studied in a $4{\times}4$ Latin Square Design. The CSL was used to ensile 5% UTWS at the rate of 0, 3, 6, and 9% on a dry matter (DM) basis. Total N and neutral detergent fibre (NDF) were increased with increasing level of CSL. Increased NDF content was attributable to increased neutral detergent insoluble nitrogen. Four diets were formulated to contain 20% concentrate and 80% UTWS ensiled with 0, (control), 3 (CSL3), 6 (CSL6), and 9% CSL (CSL9). All diets were mixed daily and fed at 1.5% of body weight twice daily. Ruminal NH3 concentration decreased with level of CSL used to ensile UTWS at 3 and 6 h post prandial, however, at 9 h post parandial it was similar across all diets and at 12 h post prandial was higher with diets containing UTWS ensiled with CSL. Concentrations of total ruminal volatile fatty acid and acetate were increased with the CSL level used to ensile UTWS. Increased rate of disappearance and reduction in lag time of DM and NDF was recorded with diets containing UTWS ensiled with CSL. Dry matter and NDF digestibilities were higher with CSL diets than on the control diet. Buffalo bulls retained more N with diets containing UTWS ensiled with CSL. The present results indicated that UTWS could be ensiled with CSL to improve its nutritive value and N utilization by ruminants.

• 한국세라믹학회지
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• 제41권9호
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• pp.657-662
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• 2004

마그카본계 내화물의 산화저항성을 증대시키기 위하여 섭씨 100$0^{\circ}C$에서 120$0^{\circ}C$에서 산화기구를 조사하고, TiC를 첨가하여 산화저항성 증가에 대한 효과를 관찰하였다. 산소공급을 위해 공기를 분당 0.2리터의 속도로 흘려주었으며 열천칭으로 무게변화가 없어질 때까지 매 30초 간격마다 무게감소를 측정하였다 본 실험에서 사용된 마그카본계 시편의 산화거동과 관련한 유효확산 계수는 1.39${\times}$$10^{-4}$ $m^2$/sec이다. 이러한 실험조건에서 총체적인 산화공정은 산화된 기공층을 통하여 내부로 향하는 산소의 확산에 의해 지배되는 반응으로 해석할 수 있다. TiC를 첨가한 시편은 마그카본계 내화물의 산화 저항성을 증대시켰다.

• 한국환경과학회지
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• 제19권12호
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• pp.1431-1445
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• 2010

In order to clarify the impact of regional warming on the meteorological field and air quality over southeastern part of Korean Peninsula, several numerical experiment were carried out. Numerical models used in this study are WRF for the estimate the meteorological elements and CMAQ for assessment of ozone concentration. According to the global warming impact, initial air temperature were changed and its warming rate reach at 2 degree which was based on the global warming scenarios provided by IPCC. The experiments considering the global warming at initial stage were presented as case T_UP. Air temperature over inland area during night time for case T_UP is higher than that for Base case. During time since the higher temperature over inland area is maintained during daytime more intensified sea breeze should be induced and also decrease the air temperature in vicinity of coast area. In case of T_UP, high level concentrations ozone distribution area was narrowed and their disappearance were faster after 1800LST. As a results, wind and temperature fields due to the global warming at initial stage mainly results in the pattern of ozone concentration and its temporal variation at South-Eastern Part of the Korean Peninsula.

• Bulletin of the Korean Chemical Society
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• 제23권9호
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• pp.1229-1258
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• 2002

This paper reports the photochemical reduction of benzil 1 to benzoin 2 and the reduction of 2 to hydrobenzoin 4 in deoxygenated solvents in the presence of triethylamine (TEA) and/or TiO2. Without TEA or TiO2, the photolysis of 1 resulted in very low yield of 2. The presence of TEA or TiO2 increased the rate of disappearance of 1 and the yield of 2, which were further increased considerably by the presence of water. The photoreduction of 1 to 2 proceeds through an electron transfer to 1 from TEA or hole-scavenged excited TiO2 followed by protonation. In the reaction medium of 88 : 7 : 2 : 3 CH3CN/CH3OH/H2O/TEA with 2.5 $㎎/m{\ell}$ of TiO2, the yield of 2 was as high as 85 % at 50 % conversion of 1. The photolysis of 2 in homogeneous media resulted in photo-cleavage to benzoyl and hydroxybenzyl radicals, which are mostly converted to benzaldehyde. The reduction product 4 is formed in low yield through the dimerization of hydroxybenzyl radicals. The addition of TEA increased the conversion rate of 2 and the yield of 4 significantly. This was attributed to the scavenging effect of TEA for benzoyl radical to produce N,N-diethylbenzamide and the photoreduction of benzaldehyde in the presence of TEA. The ratio of $(\pm)$ and meso isomers of 4 obtained from the photochemical reaction is about 1.1. This ratio is the same as that from the photochemical reduction of benzaldehyde in the presence of TEA. In the TiO2-sensitized photochemical reduction of 2, meso-4 was obtained in moderate yield. The reduction of 2 to 4 proceeds through two consecutive electron/proton transfer processes on the surface of the photocatalyst without involvement of ${\alpha}-cleavage$. The radical 11 initially formed from 2 by one electron/proton process can also combine with hydroxy methyl radical, which is generated after hole trapping of excited TiO2 by methanol, to produce 1,2-diphenylpropenone after dehydration reaction.

• 대한화학회지
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• 제39권5호
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• pp.350-355
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• 1995

요오드와 테트라메틸주석간의 전하이동에 따른 상호작용을 사염화탄소 용매내에서 분광학적 방법으로 연구하였다. 이들의 결과로부터 일시적인 전하이동 착물의 흡수 스펙트 럼(${\lambda}_{max}=270nm$)이 관찰되었으며, 흡수스펙트럼의 후속적인 감소현상으로 요오드에 의한 테트라메틸주석의 분해반응임을 알았다(iodoedestannylation). 따라서 Iodoedestannylation에 대한 속도 상수를 온도 10, 25 및 $35^{\circ}C$ 압력을 1200 bar까지 변화 시켜가면서 측정하였으며, 이때의 반응속도상수는 온도와 압력에 따라 증가함을 알았다. 이 반응속도 상수로부터 ${\Delta}V^{\neq},\;{\Delta}{\beta}^{\neq},\;{\Delta}H^{\neq}$ 및 ${\Delta}S^{\neq}$의 값을 구했으며 이들 값으로부터 전이상태의 용매구조 변 화 및 메카니즘을 규명하였다. 이러한 사실로부터 본 반응은 $S_F2$ 메카니즘이 지배적 이며 압력이 증가함에 따라 $S_F2$의 성격이 약화됨을 알았다.

• Asian-Australasian Journal of Animal Sciences
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• 제18권6호
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• pp.816-824
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• 2005

The effects of the nonionic surfactant Tween 80 and a mixture of fibrolytic enzymes on total tract digestion, in situ disappearance (ISD) and ruminal fermentation characteristics of orchardgrass hay and barley grain were investigated in a 4${\times}$4 Latin square experiment with 4 non-lactating Holstein cows and 4 diets in 4 periods. Cows were offered a total mixed ration of 50% rolled barley grain and 50% orchardgrass hay treated with either 1) water (control), 2) 0.2% (vol/wt) Tween 80, 3) 0.2% (vol/wt) hydrolytic enzyme, or 4) 0.2% hydrolytic enzyme plus 0.2% Tween 80. Total tract digestibility coefficients of DM, nitrogen, NDF and ADF were not affected (p>0.05) by dietary treatment. Compared to the control, the rate of ISD of DM from orchardgrass hay was faster (p<0.05) in cows receiving diets treated with the enzyme alone or with enzyme plus Tween 80 (0.06/h vs. 0.076 and 0.069/h). The rate of digestion was lower (p<0.05) as compared to control when barley grain was treated with these additives. Ruminal fluid pH and concentrations of total VFA, acetate, isobutyrate and butyrate were not affected (p>0.05) by treatments. Cows that consumed diets treated with enzyme plus Tween 80 had higher (p<0.05) ruminal concentrations of propionate and isovalerate, and lower (p<0.05) acetate:propionate ratios. Compared to the control, microbial protein synthesis tended (p = 0.13) to increase with the addition of enzyme to the diet while nonammonia nitrogen flow to the duodenum increased (p<0.05) with both enzyme and Tween 80 treatments. The study indicated that fibrolytic enzymes alone or in combination with Tween 80 could enhance ISD of orchardgrass hay and ruminal concentrations of propionate, valerate and iso-valerate, but do not affect total tract digestibility.

• Asian-Australasian Journal of Animal Sciences
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• 제20권9호
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• pp.1424-1432
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• 2007

Two male, rumen fistulated crossbred Brahman-Thai native beef cattle (body weight = $400{\pm}50$ kg), fed on rice straw as a source of roughage, were used as rumen fluid sources. The treatments were $2{\times}3$ factorial arrangements; two roughages (fresh cassava foliage and cassava hay) and three sulfur levels (elemental sulfur) at 0.2 (control), 0.5 and 1% of DM, respectively. The experiment revealed that the rates (c) of gas production, ammonia-nitrogen concentration, true digestibility, total concentration or molar proportions of VFA and microbial biomass were not significantly different between cassava hay and fresh cassava foliage. However, all parameters for cassava hay were higher than for fresh cassava foliage. The supplementation of 0.5% sulfur to fresh cassava foliage resulted in a significant increase in the rate of gas production, true digestibility, total concentration of VFA, microbial biomass, rate of HCN disappearance, thiocyanate appearance and cyanide percentage conversion into thiocyanate. However, there were no effects of sulfur supplementation at 0.2, 0.5 and 1% to cassava hay. The finding suggests the utilization of cassava foliage for rumen microorganisms in terms of fermentation and HCN detoxification could be improved by sulfur supplementation of 0.5% of DM.