The formation of CaCO3 in microalgal culture is investigated and applied for effective separation of microalgae. The presence of several cationic ions in the culture medium mediates the formation of 3 types of mineral precipitates depending on the concentration of mineral precursors, Ca2+ and CO3 2−, amorphous nano-flakes, rhombohedral calcites, and spherical vaterites. While amorphous phased precipitates are formed for all concentrations of mineral precursor, only calcites are formed for 30 mM solutions of mineral precursor, and mixtures of calcites and vaterites are formed for 50 and 100 mM solutions of mineral precursor. The harvesting efficiency is also dependent on the concentration of the mineral precursor: from 90 % for 10 mM to 99 % for 100 mM after 60 mins’ of gravitational sedimentation. The formation of nano-flakes on the surface of microalgal cells induces the flocculation of microalgae by breaking the stable dispersion. The negatively charged surface of the microalgal cell is compatible not only with nano-flake attachment but also with the growth of calcitic crystals in which microalgal cells are embedded.

This study was conducted to assess the effect of acidification of pig slurry on nitrogen (N) mineralization and its environmental impacts during pig slurry fermentation. Different inorganic and organic acids were used to acidify pig slurry. Four treatments including non-acidified pig slurry (control), pig slurry acidified with sulfuric acid, lactic acid, and citric acid were allocated with three replications. The total N content in the acidified pig slurry was higher than non-acidified pig slurry after fermentation. Acidification tended to increase total N content in pig slurry. Ammonium N (NH4 +-N) released from pig slurry was obviously increased at 7 days after incubation, representing 61.4%, 36.8%, and 37.4% increase in the acidified pig slurry with sulfuric acid, lactic acid, and citric acid, respectively. Nitrate N (NO3 --N) in the acidified pig slurry with sulfuric acid was the highest throughout the experiment period, but non-significant effect of organic acid. A large portion of ammonia (NH3) emission occurred within 10 days, corresponding to more than 55% of total NH3 emission. Total cumulative NH3 emission during the experimental period was lower 91% (2.9 mg N kg-1), 78% (7.3 mg N kg-1), and 81% (6.2 mg N kg-1) in the acidified pig slurry with sulfuric acid, lactic acid, and citric acid, respectively, than non-acidified pig slurry (32.7 mg N kg-1). These results suggest that acidification of pig slurry (particularly with sulfuric acid) can be faced as a good strategy to reduce NH3 emission without depressing the mineralization process.

멕시코 중부 산 루이스 포토시주의 기반암은 상부 고생대 변성암으로 구성되어있으며, 산 루이스 포토시주의 북 동쪽에 위치한 시에라 데 카토르세 중심부에 노출되어있다. 고생대 기반암을 부정합으로 덮고 있는 퇴적층은 상부 쥬라기 해성층으로 구성되며, 자카테카스층과 상부 트라이아스기 육성 우이자찰층의 적색층준과 일치한다. 이들 층은 쥬라기 라 호야 적색층 또는 상부 쥬라기 해성층에 의해 부정합으로 덮혀있다. 산 루이스 포토시주에서, 이 층위에는 백악기 석회질 해성층이 정합으로 놓여있다. 신생대층들은 상기한 암석들중 일부를 부정합으로 덮고 있으며, 해성 쇄설암 뿐만아니라 미분화된 화산암들로 구성된다. 현존하는 관입 화성암들은 산성 내지 중성 조성이며 변성 기반암 및 퇴적암을 관입한다. 플라이스토세에 증발성 퇴적물을 수반한 역암들이 퇴적되었다. 제4기 지질은 현무암류, 산록퇴적물, 충적층, 증발암 및 염류 피각층으로 구성되어있다. 산 루이스 포토시 주에는, 매우 다양한 금속 및 비금속 광상유형이 알려져있다. 이들 광상의 모암은 매우 다양하며 고생대부터 제3기까지를 구성하는 층들을 포함한다. 광화연령은 약 75%가 제3기이며 주로 후생성 광상이다. 결론적으로, 멕시코 산 루이스 포토시주의 지질-자원 정보는 향후 국내기업이 멕시코 의 광업분야 진출시 금속 및 비금속 광화대 부존지 예측 및 유망광화대 선정에 활용될 것으로 판단된다.

Soil is the main nitrogen (N) provider for plants but N in soil is not all available to advanced plants. Mineralization is a critical biological process for transferring organic N to inorganic N that can be used by plants directly. To investigate the effect of different levels of soil temperature and water content to soil mineralization, a field experiment was established on three different sites (A, B and C). We measured soil temperature, moisture and electrical conductivity once daily after swine slurry application. Average soil moisture and temperature in site A is the highest among three sites (40.9% and 9.7°C, respectively). Following is in site C (37.3% and 9.6°C) and the lowest is in site B (28.0% and 9.0°C). Ammonium N (NH4+-N) and nitrate N (NO3--N) were determined on the first and fifth day after treatment. Compared with site B and C, site A always had the highest soil total N content (1.54 g N kg-1 on day one; 1.22 g N kg-1 on day five) and highest NO3-- N content (93.18 mg N kg-1 on day one; 16.22 mg N kg-1 on day five) and a significant decrease on day five. Content of NH4+-N in site B and C reduced while in site A, it increased by 6.7%. Results revealed that net N mineralization positively correlated with soil temperature (P<0.5, r=0.675*) and moisture (P<0.01, r=0.770**), suggesting that to some extent, higher soil moisture and temperature contribute more to inorganic N that can be used by plants.

Resveratrol (3,4',5,-trihydroxystilbene), a phytoalexin present in grapes, exerts a variety of actions to reduce superoxides, prevents diabetes mellitus, and inhibits inflammation. Resveratrol acts as a chemo-preventive agent and induces apoptotic cell death in various cancer cells. However, the role of resveratrol in odontoblastic cell differentiation is unclear. In this study, the effect of resveratrol on regulating odontoblast differentiation was examined in MDPC-23 mouse odontoblastic cells derived from mouse dental papilla cells. Resveratrol significantly accelerated mineralization as compared with the control culture in differentiation of MDPC-23 cells. Resveratrol significantly increased expression of ALP mRNA as compared with the control in differentiation of MDPC-23 cells. Resveratrol significantly accelerated expression of ColⅠmRNA as compared with the control in differentiation of MDPC-23 cells. Resveratrol significantly increased expressions of DSPP and DMP-1 mRNAs as compared with the control in differentiation of MDPC-23 cells. Treatment of resveratrol did not significantly affect cell proliferation in MDPC-23 cells. Results suggest resveratrol facilitates odontoblast differentiation and mineralization in differentiation of MDPC-23 cells, and may have potential properties for development and clinical application of dentin regeneration materials.

In this study, we investigated the effect of bisphosphonate on the osteoblastic differentiation of human dental stem cells (hDPSCs). In the first experiment, we evaluated the effect of bisphosphonate on the differentiation of hDPSCs into osteoblasts by alkaline phosphatase staining after culturing hDPSCs. As a result, on day 13, the osteogenic differentiation of hDPSC was suppressed at 5 μM in clodronate and 2 μM in zolendronate. In NBP, osteogenic differentiation is more suppressed. In second experiment, cytotoxicity and proliferation test, the cell proliferation (examined by MTT assay) was more suppressed as the concentrations of zolendronate were larger than those of alendronate and clodronate. Western blotting, a third experiment, was found that AKT phosphorylation was inhibited in cell signaling proteins involved in cell proliferation inhibition and death by bisphosphonate concentration. In human dental stem cells, bisphosphonates inhibit osteoblast differentiation, and this phenomenon is clearly observed in NBPs (zolendronate), and it has been found that it is related to AKT phosphorylation of cell signaling proteins.

In order to compare greenhouse gases emission from different animal manures and to explore how different animal manures effect on soil mineralization, three kinds of materials, cattle, goat and chicken manure were amended to soil for 14 days incubation as CtS (cattle manure-amended soil), GS (goat manure-amended soil) and ChS (chicken manure-amended soil). Cumulative NH3 emissions in all treatments were rapidly increased until day 7 and then it was slightly increased in three manure-amended soils but maintained in control until day 14. GS had the highest NH3 emission at 0.14 mg kg-1 during the entire experimental period. Emissions of CO2 were highly increased by 7.8-, 9.0- and 12.4-fold in CtS, GS and ChS, respectively, compared to control at day 14. A significant increase of N2O emission in all treatments occurred within 5 days and then it was slightly increased until day 14. N2O emission was 2-fold higher in all manure-amended soils than that of control. Compared to day 1, inorganic N (NH4 + plus NO3 --N) content was highly increased in all four treatments at day 14. The increase rate was the highest in CtS treatment. Net N mineralization was increased by 4.0-, 2.4- and 2.9-fold in CtS, GS and ChS, respectively, compared to control. These results indicate that increase of NH3, CO2 and N2O gas emissions was positively related to high N mineralization.

Osteocalcin (OC) is the most abundant noncollagenous protein of extracellular matrix in the bone. In an OC deficient mouse, bone formation rates are increased in cancellous and cortical bones. OC is known as a negative regulator of mineral apposition. OC is also expressed in the tooth of the rat, bovine, and human. However, little is known about OC during tooth development in Xenopus. The purpose of this study is to compare the expression of OC with mineralization in the developing tooth of Xenopus, by using von Kossa staining and in situ hybridization. At stage 56, the developmental stage of tooth germ corresponds to the cap stage, and an acellular zone was apparent between the dental papilla and the enamel organ. From stage 57, calcium deposition was revealed by von Kossa staining prior to OC expression, and the differentiated odontoblasts forming predentin were located at adjoining predentin. At stage 58, OC transcripts were detected in the differentiated odontoblasts. At stage 66, OC mRNA was expressed in the odontoblasts, which was aligned in a single layer at the periphery of the pulp. These findings suggest that OC may play a role in mineralization and odontogenesis of tooth development in Xenopus.

유기농업에 자주 이용되는 축분퇴비와 작물잔사를 이용하여 질소무기화율을 추정하기 위한 항온실험을 수행하였다. 순무기화량은 유기자재 처리시 토양중 무기화된 질소(NH4-N + NO3-N)에서유기자재를 처리하지 않은 토양의 무기화된 질소량을 빼서 계산하였다. 담수 조건(논토양조건)에서 용출법을 이용하여 25oC에서 0, 1, 2, 3, 4, 6, 8, 16, 21주차에 무기화량을 조사하였다. 담수조건의 토양에 유기자재를 혼합한 후 지속적으로 물로 무기화된 질소를 용출하고 용출된 무기질소의 합을 이용한 무기화량을 추정하였다. 투입된 자재는 옥수수잔사, 알팔파, 수단그라스, 수수, 들깨잔사, 볏짚, 배추, 별꽃, 네마장황, 퇴비I, 퇴비II, 퇴비III, 유박, 토마토잔사, 수박잔사, 피마자박, 요소 이었고, 수행된 결과를 요약하면 다음과 같다. 1. 알팔파는 가장 높은 질소용출량을 나타내었다. 2. 자재 투입으로 토양 중 질산태 질소는 축적되지 않았다. 3. 침출수 중 암모니아태 질소의 누적량은 대부분의 유기자재에서 탄질비가 낮을수록 높은 무기화량을 보였다. 4. 볏짚과 퇴비I과 II를 제외한 대부분의 유기자재는 인산의 무기화를 증가시키지는 못하였다.

It is not yet clear to know how normal human osteoblasts(NHost) from oral and maxillofacial area deposit, stabilize, and configure their extracellular matrix on dental biomaterial surfaces. Therefore it is necessary to design biomaterials with improved biocompatibility that will promote earlier bone differentiation and mineralization. There is now increasing evidence that TGase 2 may play a role in the initiation and regulation of the mineralization processes and serves to cross-link osteocalcin and osteopontin, which are predominant substrates for TGase 2 expressed during bone mineralization. But it is still unclear as to which TGase 2 is expressed by NHost in vitro bone formation. The purpose of this s tudy was t o determine the level of TGase 2 expression associated with collagen I , osteopontin and osteocalcin in NHost cell lines from oral and maxillofacial area in vitro. We will investigate whether TGase 2 has an active role in the biocompatibility of dental biomaterials during differentiation and mineralization of NHost. NHost cell lines were cultured under DMEM with 10% FBS at 37ﾟC and 5% CO2. Collagen quantification, mineralization and calcium assay, ALP activity assay, and RT-PCR analysis during bone differentiation and mineralization were done. ALP levels showed higher activity under AA+hGP t han under AA. I nhibition o f T Gase 2 by cystamine showed d ecreased Ca++ concentration, c ollagen I deposition and ALP level during 11 days of differentiation. TGase 2 mRNA expression of NHost was constant during mineralization stage. TGase 2 enzyme activity was increased during differentiation. Osteopontin mRNA expression during mineralization was higher than that of osteocalcin and collagen I . It suggested that TGase 2 associated with collagen I, osteocalcin and osteonectin might play a role in the differentiation of NHost from oral and maxillofacial area, but a little involved in mineralization.

Substance P (SP) is known to be expressed in the nerve fibers of dental pulp and periodontal tissues. It was recently reported that SP expression increased in response to orthodontic force. In the present study, we investigated the effect of SP on expression of mineralization markers and heme oxygenase-1 (HO-1) in human immortalized periodontal ligament (IPDL) cells. Cell viability was measured using a 3,4,5-dimethylthiazol-2-yl-2,5-diphenyl tetrazolium bromide (MTT) assay. The expression of mineralization markers, including alkaline phosphatase (ALP), osteonectin (ON) and bone sialoprotein (BSP), and heme oxygenase-1 (HO-1) was assessed by reverse transcription-polymerase chain reaction (RT-PCR) and Western blot analysis. SP did not significantly change human IPDL cell viability, with the exception of the 24 hour treatment group. Treatment of human IPDL cells with 10-10 to 10-⁴M SP upregulated mineralization marker and HO-1 expression in a time- and concentration-dependent manner. Our results suggest that SP may modulate osteoblastic cell differentiation of human IPDL cells through a mechanism involving HO-1 expression.

Cementum is a hard connective tissue, produced by cementoblasts during tooth root formation, which provides for the attachment of the periodontal ligament to the roots and surrounding alveolar bone. Establishment of this attachment is an important event in the regeneration of lost periodontal tissues. We examined whether or not odontoblast conditioned media(CM) have a regulatory influence on the differentiation and mineralization of cementoblasts(murine cementoblastic cell line, OCCM-30) in vitro. To identify the effect of odontoblast conditioned media and dentin non collagenous proteins (dNCPs) on cementoblast differentiation and mineralization, we treated CM and dNCPs to cementoblast then differentiated the cells for 14 days. To evaluate the formation of mineralized nodules alizarin-red S staining was performed at 0,4,7 and 14 days. Expression of cementum matrix genes was measured by RT-PCR. Mineralization of cementoblasts was accelerated with CM from odontoblastic MDPC-23 and OD-11. The expression of BSP, ALP, and OC mRNA in cementoblastic OCCM-30 cells was facilitated by the MDPC-23 and OD-11 cells. The extracted dNCPs had little influence on the proliferation, cell cycle modification, and chemotaxis of OCCM-30 cells. Although the dNCPs did not exhibit chemotactic activities for cementoblasts, the dNCPs promoted the differentiation and mineralization of cementoblasts. In conclusion, the dentin matrix protein, or the secreted products of odontoblast, facilitates cementoblast differentiation and mineralization. This represents a new approach and suggests another avenue for cementum regeneration.

수왕금은광상은 백악기 중기의 반상화강암이나 선캠브리아기의 소백산 편마암 복합체에 발달한 열극을 충진한 석역맥에서 산출된다. 광물공생군에 대한 연구결과 광화작용은 4시기에 걸쳐서 일어났다. 광화 띠는 주요황화광물과 소량의 에렉트럼, 광화 II기는 에렉트럼, 광화 III기는 함은황화염광물과 소량의 에렉트럼, 그리고 광화IV기는 광석광물정출과 무관한 시기이다. 광물학적 연구 및 유체포유물 연구결과 수왕광상의 광석광물은 초기에는 고온(300˚C)에서 정출하여 후기로 가면서 온도가 150˚C까지 하강하는 경향을 보이고, 염농도는 섬아연석의 10.4wt.%에서 중정석의3.1wt.%의 영역을 보여준다. 수왕광상의 금은 광화작용은 140∼250˚C의 온도와 황분압이 10-12∼10-18 atm을 갖는 광화유체에서 일어났다. 유체포유물의 비등증거로부터 광화작용이 진행되는 동안의 압력 조건은 정암압 환경에서 약 210bars 정도로 추정되며, 이는 대략 약 800m의 심도에서 광화작용이 일어났음을 시사한다.

설화 광산의 중열수(中熱水) 금광상은 경기육괴의 화강암류내에 발달된 북동방향 단층 전단대를 충진한 괴상의 단성 석영맥내에 배태되어 있다. 설화 중열수 금광화작용(金鑛化作用)은 쥬라기 화강암류(161Ma)와 공간적으로 관련되어 있다. 맥상 석영은 3개유형의 유체포유물(流體包有物)을 포함하고 있다: 1) 저염농도(〈5wt.% NaCl)의 액상 CO2를 배태한 type IV 유체포유물; 2) 가스가 풍부(〉70vol.%)하고, 기상으로 균질화하는 type II 유체포유물; 3) 소량의 CO2를 포함하는 저내지 중염농도(0∼15 wt.% NaCl)의 type I 유체포유물. H2O-CO2-CH4-N2-NaCl계 유체포유물은 250˚ ∼430˚C 온도와 1kbar 압력에 해당되는 액상선을 따라 초기에 포획된 불혼화 유체를 지시한다. 정밀 유체포유물 연구에의하면, 함금 광화작용중 점진적인 압력감소가 발생했음을 알 수 있다. 수용성 포유물의 유체는 온도 및 압력감소로 인한 균질한 H2O-CO2-CH4-N2-NaCl계 유체로부터 광역적인 유체의 불혼화(CO2-CH4 비등)작용을 거쳐 진화된 후기 유체이거나, 광화지역의 융기 및 삭박과 관련된 심부순환천수의 영향을 받았던 것으로 추정된다. 초기 유체는 균질한 H2O-CO2-CH4-N2-NaCl계 유체로서 다음과 같은 특성을 보인다: 〉250˚∼430˚C, 0.16∼0.62의 XCO 2, 5∼14mole% CH4, 0.06∼0.31mole% N2, 0.4∼4.9wt.% NaCl의 염농도. 설화 금광산의 온도-조성 자료는 설화 함금열수계가 화강암질 용융체와 인접한 부분에 정치되어 있었음을 지시한다. 이러한 화강암질 용융체는 CH4 형성을 촉진시켜 유체를 환원상태로 변환시킨 것으로 추정된다. 철황화물중 자류철석이 지배적으로 산출됨은 환원유체 상태를 지시하고 있다. 황화광물의 δ 34S값(-0.6 ∼ 1.4%o)은 황의 심부 화성기원을 지시하고 있다.