Osteoclasts are multinucleated cells with bone resorbing activity and differentiated from hematopoietic cell lineages of monocyte/macrophages in the presence of receptor activator of NF-xB ligand (RANKL) and M-CSF. However, the exact molecular mechanisms through which RANKL stimulates osteoclastogenesis remain to be elucidated. Here we report that activation of cAMP-response elementbinding protein (CREB) is not involved in osteoclastogenesis from osteoclast precursors in response to RANKL. RANKL induced CREB activation in osteoclast precursors. Using pharmacological inhibitors, we found that RANKL-induced CREB activation is dependent on p38 MAPK pathways. We also found that ectopic expressions of wild type and dominant negative forms of CREB in osteoclast precursors did not affect RANKL-induced osteoclast formation and bone resorbing activity. Furthermore, dominant negative forms of CREB did not alter the expression levels of osteoclast-specific marker genes. Taken together, these data suggest that CREB is dispensable for differentiation and resorbing activity of osteoclasts.

이 논문은 SnO2에 소량의 Pd를 첨가하여 이것을 Al2O3기판위에 진공증착시켜 가스소자를 제작한 후, 소자의 감지특성에 영향을 미치는 열처리 온도, 소자의 온도, Pd의 첨가량의 변화 효과를 조사한 것이다. 소자의 열처리 온도가 550˚C일때와 소자의 동작온도가 350˚C일때 ethanol gas에 접촉시 소자 저항이 가장 낮았다. Pd 1 wt%를 첨가한 경우 에탄올 가스에 대한 소자의 감지특성이 가장 양호하였으며, 저농도 영역에서 특히 우수하였다.

이 연구에서는 단일 활성화제로 활성화시킨 슬래그 기반 섬유보강 복합재료의 초기재령에서 인장거동을 조사하였다. 실험 결과, 활성화제 종류에 따라 재령 7일에서 균열강도, 인장강도, 인장변형성능에 차이가 있었으며, 규산나트륨을 활성화제로 사용한 배합이 가장 큰 인장변형성능을 나타내었다.

품질의 변동성이 많은 순환유동층 플라이 애시를 현장에서 혼화재로 사용하는 것 보다 수경성 시멘트의 초기강도 발현을 위한 자극제로 활용할 수 있는 가능성을 판단하고자 하였으며, 이를 위하여 다양한 조건의 시멘트 조합을 사용하여 강도특성을 실험적으로 분석하였다. 실험을 통하여 순환유동층 보일러 플라이애시의 free CaO와 반응성 CaO가 수경성 시멘트 품질에 미치는 영향을 분석하였으며, 석고를 대체할 수 있는 결합재로 활용이 가능함을 확인하였다.

This study is to perform experiment of concrete according to addition of blast furnace slag powder and sulfur activator dosages. Blast furnace slag powder used at 30, 50, 80% replacement by weight of cement, and liquid sulfur additives was chosen as the alkaline activator. As a result, it should be noted that the sulfur alkali-activators can not only solve the disadvantage of blast furnace slag concrete but also offer the chloride resistance of alkali-activated blast furnace slag concrete to blast furnace slag concrete.

In this study, the performance of the self-healing with the granulated alkali activator (Ca(OH)2) manufactured in seawater environment is investigated for crack healing under 300 μm of cracks. Specimens combined with GGBFS and OPC with and without the granulated alkali activator were manufactured and immersed in seawater. After that, crack recovery on the surface of the specimens with the granulated alkali activator (Ca(OH)2) was also evaluated by the ultrasonic pulse velocity test. From the results, it was verified that cementitious materials with the granulated alkali activator, exposed in marine environments, could be able to heal or seal inside cracks

Genetic variations of γ-/ω-gliadin and Spa (storage protein activator) in 40 Korean wheat cultivars were evaluated to provide genetic information for improving end-use quality in wheat breeding programs. Korean wheat cultivars were classified into 13 patterns at the Gli-1 locus based on the allelic variation using A-PAGE (acidic-polyacrylamide gel electrophoresis). Seven, five, and six alleles were identified at Gli-A1, Gli-B1, and Gli-D1 loci, respectively. Allele-specific PCR markers for γ-gliadin corresponded to specific allele at Gli-1 loci on A-PAGE, which Gli-A1f, Gli-A1h and Gli-A1l alleles corresponded to GliA1.2, Gli-B1h and Gli-B1f alleles corresponded to GliB1.2 and Gli-D1f, Gli-D1m and Gli-D1o alleles corresponded to GliD1.1. DNA markers for γ-45 and γ-42 also corresponded to the γ-gliadin patterns around 40kDa on A-PAGE, except in Sukang, Ol and Joongmo2003. However, allelic specific PCR markers for ω5-gliadin did not correspond to that of A-PAGE. Three alleles were identified at Spa-A1 locus, whereas there was no variation at Spa-B1 and Spa-D1 loci.

본 연구는 혼합 활성화제에 의한 알칼리 활성화 슬래그 시멘트(AASC)의 역학적 특성에 관한 연구이다. 사용된 활성화제는 황산칼슘(CaSO4, 이하 CS), 황산나트륨(Na2SO4, 이하 SS) 및 수산화나트륨(NaOH)이다. 황산염은 슬래그 중량의 2.5, 5.0, 7.5 및 10.0%로 치환하여 사용하였으며, NaOH는 2M 및 4M 농도의 수용액으로 사용하였다. 본 연구에서는 황산염(CS 및 SS) 치환율에 따른 배합(4가지 배합)과 2M 및 4M의 각각의 NaOH 수용액에 치환된 황산염을 혼합하여 시험체를 제작하였다. 시험체는 총 24가지의 배합에 따라 페이스트로 제작되었으며, 물－결합재 비는 0.5로 하였다. 경화된 시험체에 대해서 압축강도, 휨강도, 초음파속도(UPV), 흡수율 및 XRD 분석을 수행하였다. CS의 활성화제를 사용한 경우는 7.5% CS 치환율, 2M NaOH 수용액+ 5.0% CS 치환율 및 4M NaOH 수용액+ 5.0% CS 치환율의 시험체에서 최고의 압축강도를 나타내었다. 또한, SS의 활성화제를 사용한 경우는 10.0% SS 치환율, 2M NaOH + 7.5% SS 치환율 및 4M NaOH + 2.5% SS 치환율에서 최고의 압축강도 발현을 나타내었다. 휨강도, UPV 및 흡수율은 압축강도 발현 결과와 유사한 경향을 나타내는 것을 알 수 있었으며, XRD 분석결과 시험체 내에 생성된 반응물질은 ettringite, CSH 및 실리케이트계 수화물인 것으로 나타났다. AASC에서 황산염과 NaOH의 혼합 사용은 황산염의 단독 사용의 경우와 비교하여 일정 수준의 농도 범위에서 강도를 향상시키고 조직을 치밀화 시키는 등의 긍정적인 영향을 미치는 것으로 판단된다.

In this study, it was developed eco-friendly alkali-activated slag fiber reinforced concrete using ground granulated blast furnace slag, alkali activator (water glass, sodium hydroxides), and steel fiber. Eight reinforced concrete beam using alkali-activated slag concrete were constructed and tested under monotonic loading. The major variables were mixture ratio of alkali activator, mixed/without of steel fiber. Experimental programs were carried out to improve and evaluate the flexural performance of such test specimens, such as the load-displacement, the failure mode, the maximum load carrying capacity, and ductility capacity. All the specimens were modeled in scale-down size. The reinforced concrete beams using the eco-friendly alkali-activated slag fiber reinforced concrete was failed by the flexure or flexure-shear in general. In addition, the maximum strength increased with the adding the mol of sodium hydroxide, and the specimen reinforced the steel fiber showed the value of maximum strength which is increased by 15.8% through 25.9%. It is thought that eco-friendly alkali-activated slag fiber reinforced concrete can be used with construction material and product to replace normal concrete. If there is applied to structures such as precast concrete member and production of 2nd concrete product, it could be improved the productivity and reduction of construction duration etc.

Proportion of elderly patients is gradually increasing in the republic of Korea. However, intravenous recombinant tissue plasminogen activator (rt-PA) therapy is recently not recommended in elderly acute ischemic stroke patients, although old age is not a proven contraindication to intravenous rt-PA. The purpose of this study was to investigate the safety and prognosis of intravenous thrombolysis in elderly patients.

This study is based on developing a free-cement. The Setting time of 100% GGBS(Ground Granulated Blast furnace Slag) admixed alkali-activators is measured, the influence of cation of alkali-activators on setting time is assessed. As a result, in case of mixing KOH or NaOH, setting time is getting shorter, although, GGBS admixed Ca(OH)2 has similar setting times regardless of concentration of alkali-activators.

This paper reported the effect of blended activator on the compressive strength of alkali-activated slag cement(AASC) mortar. The alkalis combinations made using sodium hydroxide(NaOH), calcium hydroxide(Ca(OH)2) and potassium hydroxide(KOH) with calcium carbonate(CaCO3). The compressive strength was increase as the dosage of caustic alkali increase.