• International Journal of Oral Biology
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• 제30권1호
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• pp.23-30
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• 2005

Bone remodeling is a process controlled by the action of two major bone cells; the bone forming osteoblast and the bone resorbing osteoclast. In the process of osteoclastogenesis, stromal cells and osteoblast produce RANKL, OPG, and M-CSF, which in turn regulate the osteoclastogenesis. During the bone resorption by activated osteoclasts, extracellular $Ca^{2+}/{PO_4}^{2-}$ concentration and degraded organic materials goes up, providing the hypertonic microenvironment. In this study, we tested the effects of hypertonicity due to the degraded organic materials on osteoclastogenesis in co-culture system. It was examined the cellular response of osteoblastic cell in terms of osteoclastogenesis by applying the sucrose, and mannitol, as a substitute of degraded organic materials to co-culture system. Apart from the sucrose, mannitol, and NaCl was tested to be compared to the effect of organic osmotic particles. The addition of sucrose and mannitol (25, 50, 100, 150, or 200 mM) to co-culture medium inhibited the number of tartrate-resistant acid phosphatase (TRAP) positive multinucleated cells induced by 10 nM $1{\alpha},25(OH)_2vitaminD_3$ ($1{\alpha},25(OH)_2D_3$). However, NaCl did exert harmful effect upon the cells in this co-culture system, which is attributed to DNA damage in high concentration of NaCl. To further investigate the mechanism by which hypertonicity inhibits $1{\alpha},25(OH)_2D_3$-induced osteoclastogenesis, the mRNA expressions of receptor activator of nuclear factor (NF)-kB ligand (RANKL) and osteoprotegerin (OPG) were monitored by RT-PCR. In the presence of sucrose (50 mM), RANKL mRNA expression was decreased in a dose-dependent manner, while the change in OPG and M-CSF mRNA were not occurred in significantly. The RANKL mRNA expression was inhibited for 48 hours in the presence of sucrose (50 mM), but such a decrement recovered after 72 hours. However, there were no considerable changes in the expression of OPG and M-CSF mRNA. Conclusively, these findings strongly suggest that hypertonic stress down-regulates $1{\alpha},25(OH)_2D_3$-induced osteoclastogenesis via RANKL signal pathway in osteoblastic cell, and may playa pivotal role as a regulator that modulates osteoclastogenesis.

• Nuclear Engineering and Technology
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• 제55권2호
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• pp.681-689
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• 2023

Purpose: Muons are characterized by a strong penetrating ability and can travel through thousands of meters of rock, making them ideal to image large volumes and substances typically impenetrable to, for example, electrons and photons. The feasibility of 3D image reconstruction and material identification based on a cosmic ray muons tomography (MT) system with triangular bar plastic scintillator detectors has been verified in this paper. Our prototype shows potential application value and the authors wish to apply this prototype system to 3D imaging. In addition, an MT experiment with the same detector system is also in progress. Methods: A simulation based on GEANT4 was developed to study cosmic ray muons' physical processes and motion trails. The yield and transportation of optical photons scintillated in each triangular bar of the detector system were reproduced. An image reconstruction algorithm and correction method based on muon scattering, which differs from the conventional PoCA algorithm, has been developed based on simulation data and verified by experimental data. Results: According to the simulation result, the detector system's position resolution is below 1 ~ mm in simulation and 2 mm in the experiment. A relatively legible 3D image of lead bricks in size of 20 cm × 5 cm × 10 cm used our inversion algorithm can be presented below 1× 10⁴ effective events, which takes 16 h of acquisition time experimentally. Conclusion: The proposed method is a potential candidate to monitor the cosmic ray MT accurately. Monte Carlo simulations have been performed to discuss the application of the detector and the simulation results have indicated that the detector can be used in cosmic ray MT. The cosmic ray MT experiment is currently underway. Furthermore, the proposal also has the potential to scan the earth, buildings, and other structures of interest including for instance computerized imaging in an archaeological framework.

• 한국토양비료학회지
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• 제27권4호
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• pp.247-254
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• 1994

인광석분말(燐鑛石粉末)의 화학(化學) 및 광물학적(鑛物學的) 특성(特性)을 구명하고 인광석분말(燐鑛石粉末)의 구용성(枸溶性) 인산함량(燐酸含量)을 증대시키기 위한 시험을 수행하여 인광석분말(燐鑛石粉末)의 직접시용(直接施用)을 위한 기초자료(基礎資料)를 얻기 위해 실시한 결과를 요약(要約)하면 다음과 같다. 1. 인광석(燐鑛石)의 주광물(主鑛物)은 인회석(燐灰石)(Apatite, $Ca_5(PO_4)_3$ OH, F, Cl) 중(中) Carbonate apatite이었으며 부광물(副鑛物)로는 방해석(方解石)과 석영(石英) 등(等)이 함유되어 있었고 시차열분석(示差熱分析)(DTA)결과를 보면 $1,000^{\circ}C$까지 뚜렷한 흡열(吸熱)이나 발열(發熱)peak를 볼 수 없었다. 2. 인광석분말(燐鑛石粉末)은 입도(粒度)가 가늘어질수록 구용성(枸溶性) 인산함량은 증가(增加)하나 수용성(水溶性) 인산함량은 입도(粒度)에 관계없이 증가(增加)하지 않았고, 소성(燒成)할 경우 소성시간(燒成時間)이 길어질수록 구용율(枸溶率)은 감소하였으며, 항온온도(恒溫溫度)가 높거나 항온시간(恒溫時間)이 길어질수록 구용율(枸溶率)이 증가하였다. 3. 인광석분말(燐鑛石粉末)을 퇴구비(堆廐肥)와 발효(醱酵)시키거나 산처리(酸處理)를 하면 인산구용율(燐酸枸溶率)이 증가하며 산농도(酸濃度)가 동일할 경우에는 황산(黃酸)이 질산(窒酸) 보다 우수하였다. 30% 황산처리(黃酸處理)는 기간이 진전될수록 구용성(枸溶性) 및 수용성(水溶性) 인산함량(燐酸含量)이 증가하였으나 당밀폐액(糖蜜廢液)처리는 크게 증가하지 않았고, 30% 황산처리(黃酸處理) 후 당밀폐액(糖蜜廢液)으로 제립(製粒)한 시험제품이 당밀폐액(糖蜜廢液)만 처리한 시험제품 보다 구용성(枸溶性) 및 수용성(水溶性) 인산함량(燐酸含量)이 높았다.

• 한국해양학회지
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• 제7권1호
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• pp.24-45
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• 1972

The Han River is an important water source in Seoul and neighbouring districts, for public and industrial supply, and for agriculture and fishery. Nowadays, more than six million inhabitants are supplied withe water from this river. The total length of the river is 470km, and has 17 10$\^$9/㎥ an average annual flow. The hydrographic characteristics at Seoul are 653㎥/sec in an average flow, 4,608㎥/sec in the maximum average flow, and 201㎥/sec in the minimum average flow. These are influenced in some degree by snowmelt in early spring, and greatly by the flood during summer. For the pollution problems, the periods of low flow are critical ones. As a rule they occur around the months November through June. Nowadays, most of the sewage from towns and industries is discharged untreated. Apart from domestic and industrial sewages, there are some discharges of mineral matter by mines in the upriver region. In general, water quality of the Han River is kept very clean and healthy until Kwangnaru of the upper region of Seoul. A large pollution, however, is received in the downstream by the domestic and industrial sewages of Seoul. It can be seen that dissolved oxygen, COD and BOD$\sub$5/ diminish markedly, and the intensity of almost every water parameter of the river continues to increase. Comparison of the figures for 1971 derived from a sampling point 40km downstream of Kwangnaru leads to the conclusion that hardness, Ca and Mg were no changed; alkalinity, Si and soluble- Fe were slightly increased; CO$\sub$2/, acidity, Cl, NO$\sub$2/-N, Cu, Zn and Al were increased in 2 and 3 times; total residue, total ignitious residue, COD, BOD$\sub$5/, NH$\sub$4/-N, PO$\sub$4/-P, Mn, Pb and total-Fe were increased in 4 to 7 times; and SO$\sub$4/, particulate-Fe and Cd were increased in 10 to 11 times. On the other hand, coliforms were increased in 650 times; fecal coliforms in 365 times; enterococci and total plate counts in 30 times, respectively. In view points of water quality standards, the down Han River water is now leveling out in Cd, coliforms and fecal coliforms for the agricultural use; in dissolved oxygen and some trace elements (Cu, Zn, Pb and Cd) for the fishery use; in ammonia, COD, BOD$\sub$5/, and Cd for the drinking use.

• 한국환경보건학회지
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• 제21권4호
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• pp.1-9
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• 1995

This study was carried to investigate the biodegradability of phenol in the wastewater with the two sludge blanket-packed bed reactor in series. Each reactor had a dimension of 0.09 m i.d. and 1.5 m height and consisted of two regions. The lower region was a sludge blanket of 0.5 m height and the upper region was a packed-bed of 1 m height. The packed bed region was charged with ceramic raschig rings of 10 mm i.d., 15 mm o.d. and 20 mm length. The reactors were operated at 35$\circ$C and the hydraulic retention time(HRT) was maintained 24 hours. The synthetic wastewater composed of glucose and phenol as major components was fed into the reactor in a continuous mode with incereasing phenol concentration. In addition, the nutrient trace metals($Na^+, Mg^{2+}, Ca^{2+}, PO_4^{3-}, NH_4^+, Co^{2+}, Fe^{2+}$ etc.) were added for growing anaerobes. The phenol concentration of the effluent, the overall gas production, the composition of product gas, the efficiency of COD reduction and the duration of acclimation period were measured to determine the performance of the anaerobic wastewater treatment system as the phenol concentration of the influent was increased from 600 to 2400 mg//l. Successfully stable biodegradation of phenol could be achieved with the anaerobic treatment system from 600 to 1, 800 mg/l of the influent phenol concentration. The upper level of influent phenol loading was high enough to meet most of the practical requirement. The duration of acclimation increased with the phenol loading. At steady state of the influent phenol concentration of 1800 mg/l, the treatment performance indicated the phenol reduction efficiency of 99%, the COD reduction efficiency of 99% and the gas production rate of 37 l/day. At the influent phenol concentration of 2400 mg/l, however, the operation of the treatment system was noted unstable. While the concentration of methane in biogas decreased with increasing the influent phenol loading, the carbon dioxide was increased. However, the concentration of hydrogen was varied negligibly. The concentration of methane was high enough to be used as a fuel. As a result, it is suggested that anaerobic phenol wastewater treament was economical in the sense of energy recovery and wastewater treatment.

• Applied Biological Chemistry
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• 제14권1호
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• pp.9-18
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• 1971

석유에 효모를 길러 식량 내지 사료로 이용할것을 목적으로 전국 각지의 100여점의 토양시료로부터 400여주의 탄화수소이용 효모균주를 분리하고 그 중 가장 균체수율이 좋은 균주를 선정하여 동정 하였다. 그 균주의 석유탄화수소 배지에서의 배양최적조건, 생육경과 및 균체조성을 조사하여 다음과 같은 결과를 얻었다. 1. 우수균주로 신정된 효모는 Candida curvata-SNU 70으로 동정되었다. 2. 선정호모의 적정 증식배지조성은 다음과같다 Light Gas Oil 30ml, $(NH_2)_2CO$ 400mg, $(NH_4)_2\;SO_4$ 100mg, $KH_2PO_4$ 670mg, $Na_2HPO_4{\cdot} 12H_2O$ 330mg. $MgSO_4{\cdot}7H_2O$ 500mg, $CaCO_3$ 3g, Yeast Extract 50mg, Tween 20 0.05ml, Tap Water 1000ml. 3. 선정효모의 배양조건은 pH $5.5{\sim}7.0,\;30^{\circ}C$, 및 충분한 통기조건이 적당함을 알았다. 4. 유가법은 특히 10% 이상의 고농도배양에서 효과를 보였다. 5. 선정효모, Candida curvata-SNU 70는 lag phase가 16시간 까지이고 다음 28시간까지가 대수기임을 알 수 있었으며, 대수기에서 비증식율, ${\mu}x$는 $0.22hr^{-1}$이고 doubling time은 3.2시간이었다. 6. 얻어진 최적조건에서 2일간 배양시켜 Light Gas Oil에 대한 균체수율 16.1%를 얻었으며 건조세포의 단백질함량은 48.4%였다.

• 생물환경조절학회지
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• 제20권3호
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• pp.189-196
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• 2011

Ebb and flow 시스템을 사용한 분화 칼랑코에 재배에서 광도와 양액 농도가 생육, 양분 흡수율 및 배지 내 무기 이온의 집적에 미치는 영향을 구명하기 위하여 본 연구를 수행하였다. 연구 목적을 달성하기 위하여 광도 3수준(PPF 4.26, 5.51, $9.75mol{\cdot}m^{-2}{\cdot}d^{-1}$)과 양액 농도 3수준(EC 1.2, 1.8, $2.4dS{\cdot}m^{-1}$)을 조합하여 요인실험으로 수행하였다. 분화 재배한 칼랑코에의 생육은 광도와 양액 농도에 뚜렷하게 영향을 받았으며, 광도가 높아질수록 생육이 양호하였다. 각 광도 내에서는 양액의 EC를 $1.8\sim2.4dS{\cdot}m^{-1}$의 범위로 조절할 경우 칼랑코에 지상부 생육이 비교적 양호하였지만, EC를 $2.4dS{\cdot}m^{-1}$로 조절한 처리의 생체중, 건물중 및 엽면적이 가장 크게 나타났다. 광도와 양액 농도는 ebb and flow 시스템의 양액 탱크로부터 양분 및 수분 흡수량과 배지 내 무기 이온의 집적에 유의하게 영향을 미쳤지만, 식물체의 무기물 함량에는 뚜렷한 영향을 미치지 않았다. 광도는 양액의 EC에 비해 이온의 흡수율에 미치는 영향이 상대적으로 적었으며, 양액 EC가 높을 수록 $NO_3^-$, P, K, Mg 이온의 흡수율은 높았다. 이상의 연구결과를 고려할 때 ebb and flow 저면 관수 시스템에서 배지 내 무기 이온 집적에 영향을 주는 주 요인은 양액 농도임을 확인하였으며, 광도와 양액의 EC를 이용하여 배지 내 무기 이온의 집적량을 예측하기 위한 회귀식을 제시하였다.

• Applied Biological Chemistry
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• 제18권1호
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• pp.16-22
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• 1975

우량탁주효모(優良濁酒酵母)로서 선정(選定)한 2모균주(母菌株)와 모균주(母菌株)에 자외선조사(紫外線照射)로서 얻은 3변이주(變異株)의 생리적(生理的) 성질(性質)을 검토(檢討)한 결과(結果)는 다음과 같다. 1) Alcohol 내성(耐性)은 모균(母菌)에 비(比)하여 3변이주(變異株)들이 약(弱)하였다. 2) 구연산 및 젖산내성(耐性)은 모균(母菌)에 비(比)하여 변이주(變異株) 인 30-81균주(菌株)는 강(强)하였으나 기타(其他) 2변이주(變異株)는 비슷 하였다. 3) 아질산염(亞窒酸鹽)의 내성(耐性)은 30-81균주(菌株)는 0.01%에서 생육(生育)하였으나 다른 2변이주(變異株)와 모균주(母菌株)는 0.1%에서 생육(生育)하였다. 4) Vitamin 요구성(要求性)에 있어서 2모균주(母菌株)와 3변이주(變異洙)는 Ca-pantothenate를 필수적(必須的)인 생육인자(生育因子)로 요구(要求)하였으며 변이주(變異洙)인 30-24균주(菌株)를 제외(除外)한 2변이주(變異株)와 2모균주(母菌株)들은 biotin을 자격적(刺激的) 생육인자(生育因子)로 요구(要求)하였다. 5) 변이주(變異株)의 번식력(繁殖力)은 모균(母菌)에 비(比)하여 약(弱)하여졌으며 특(特)히 30-81균주(菌株)가 약(弱)하였다. 6) 발효적온(醱酵適溫)은 2모균주(母菌株)는 $30-35^{\circ}C$였고 3변이주(變異株)는 $25{\sim}30^{\circ}C$ 였다. 7) 발효최적(醱酵最適) pH는 $5{\sim}6$으로 모균(母菌)과 변이주(變異株)간에 별차이(別差異)가 없었으며 30-81균주(菌株)는 중성(中性)으로 됨에 따라 타균주(他菌株)에 비(比)하여 발효력(醱酵力)이 저하(低下)되었다. 8) 20%이상(以上)의 당농도(糖濃度)에 대한 감수성(感受性)은 더욱 강(强)하였다._4H_2PO_4,\;(NH_4)_2SO_4$등이 량호(良好)하고 특히 유기질소원(有機窒素源)을 가(加)함으로써 Basal meaia에서 Inulase생산(生産)을 증가(增加)시켰다. 7. 당원(糖源)의 이용(利用)으로써는 Inulin이외(以外)의 제당(諸糖)은 Inulase생산(生産)에 영향(影響)을 미치지 않았다. 8. 금속(金屬) 염류(鹽類)의 이용(利用)은 KCI. $MgSO_4,\;FeSO_4$등이 Inulase생산(生産)을 증가(增加)시켰다.位間) 활성철함량(活性鐵含量)만으로는 불충분(不充分)하며 전철(全鐵) 대(對) 활성철(活性鐵)의 비(比) 그리고 점토(粘土) 및 미사함량(微砂含量)으로 측정(推定)한 활성철함량(活性鐵含量)을 기초(基礎)로 하여야 하며 망간의 집적층(集積層)은 전(全)망간 및 역환원성(易還元性) 망간 함량(含量)과 그들의 비(比)로 추정(推定)하여야 할 것이다.(酸) P은 후기수확(後期收穫)의 것에서 약간 높았다. 양송이중의 유리(遊離)아미노산(酸)으로는 alanine, serine, threonine glutamic acid를 위시(爲始)하여 12종(種)이 검출(檢出)되었다. 9) 본실험(本實驗)으로 재배상(栽培床) 퇴비(堆肥)의 숙성(熟成) 과정은 중온균(中溫菌)에 의한 암모니아의 생성(生成)과 탄수물화(炭水物化)의 분해에 이어 고온균(高溫菌)에 의한 단백질합성(蛋白質合成), 균경형성(菌經形成) 그리고 다실소(多室素) lignin 부식복합기(腐植複合畿)를 형성(形成)하고 이들 성분(成分)이 잔류(殘留)하는 탄수화물(炭水化物)과 함께 양송이의 영양원(營養源)을 이루게 되는 숙성기작(熟成機作)을 뒷받침 할 수 있었다.지 않았으나 ABA 처리(處理)는 이를 현저히 감소(減少)시켰다. 9) 초엽에 있어서 GA 처리(處理)는 초엽의 생장(生長) 및 chlorophyll 함량(含量)

• Journal of Periodontal and Implant Science
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• 제33권1호
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• pp.13-26
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• 2003

Periodontal regeneration therapy with bone-substituting materials has gained favorable clinical efficacy by enhancing osseous regeneration in periodontal bony defect. As bone-substituting materials, bone powder, calcium phosphate ceramic, modified forms of hydroxyapatite, and hard tissue replacement polymer have demonstrated their periodontal bony regenerative potency. Bone-substituting materials should fulfill several requirements such as biocompatibility, osteogenecity, malleability, biodegradability. The purpose of this study was to investigate biocompatibility, osteo-conduction capacity and biodegradability of $Na_2O$, $K_2O$ added calcium metaphosphate(CMP). Beta CMP was obtained by thermal treatment of anhydrous $Ca_2(H_2PO_4)_2$. $Na_2O$ and $K_2O$ were added to CMP. The change of weight of pure CMP, $Na_2O$-CMP, and $K_2O$-CMP in Tris-buffer solution and simulated body fluid for 30 days was measured. Twenty four Newzealand white rabbits were used in negative control, positive control(Bio-Oss), pure CMP group, 5% $Na_2$-CMP group, 10% $Na_2O$-CMP goup, and 5% $K_2O$-CMP group. In each group, graft materials were placed in right and left parietal bone defects(diameter 10mm) of rabbit. The animals were sacrificed at 3 months and 6 months after implantation of the graft materials. Degree of biodegradability of $K_2O$ or $Na_2O$ added CMP was greater than that of pure CMP in experimental condition. All experimental sites were healed with no clinical evidence of inflammatory response to all CMP implants. Histologic observations revealed that all CMP grafts were very biocompatible and osseous conductive, and that in $K_2O$-CMP or $Na_2O$-CMP implanted sites, there was biodegradable pattern, and that in site of new bone formation, there was no significant difference between all CMP group and DPBB(Bio-Oss) group. From this result, it was suggested that all experimental CMP group graft materials were able to use as an available bone substitution.

• 한국균학회지
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• 제23권3호통권74호
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• pp.226-231
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• 1995

팽이버섯은 최근(最近)에 생산(生産)과 소비(消費)가 촉진(促進)되어 재배면적(栽培面積)이 급증(急增)하고 있는데 이에 소요되는 재배용(栽培用) 톱밥배지(培地) 제조시(製造時)에 부화장(孵化場) 부산물(副産物)인 계란껍질의 첨가효과(添加效果)를 구명(究明)하기 위하여 몇 가지 시험(試驗)을 수행한 결과(結果)를 요약(要約)하면 다음과 같다. 1. 배지재료(培地材料)의 화학적(化學的) 성질 중 계란껍질은 전탄소(全炭素) 20.7%, 전질소(全窒素) 0.81%이고 인과 칼슘함량은 2,530 ppm과 44.37%로 톱밥보다 많았다. 2. 배지재료 배합시 계란껍질을 첨가하면 균사생장(菌絲生長) 및 초발용소요일수(初發茸所要日數)는 무처리구(無處理區)와 차이가 없었으나 수량(收量)이 증수(增收)되는 경향이었으며 특히 계란껍질을 15% 첨가할 때 자실체(子實體) 수량(收量)이 23% 정도 증수(增收)되었다. 그러나 20% 이상 첨가시는 수량이 감소되는 경향이 있다. 3. 팽이버섯 품질(品質)은 계란껍질 $5{\sim}15%$ 첨가시 버섯 대길이 12.8 cm, 대직경 3 mm, 갓직경 9 mm로 무처리구(無處理區)와 비슷하였으나 유효경수(有效莖數)는 무처리구(無處理區)보다 11% 많았다. 4. 톱밥배지 제조시(製造時) 계란껍질을 15%까지 첨가(添加)하면 배지(培地)의 물리성(物理性)이 개선(改善)되고 인과 칼슘함량이 높아 자실체(子實體) 수량(收量)과 품질(品質)이 향상(向上)되었다.