Nowadays micro-dust is a serious problem in Korea. In particular micro-dust contains heavy metals such as Pb (lead) and Cd (cadmium) which negatively effect on human health. In this study, we intended to isolate lactic acid bacteria which can scavenge the heavy metals. Firstly we isolated two lactic acid bacteria which were resistant to Ag, Cu, and Zn (30-100 mM AgNO3, CuSO4, ZnSO4 in MRS broth). The two lactic acid bacteria CJNU 1877 and JG 15 were identified Lactobacillus paracasei and Enterococcus faecium, respectively. Subsequently the strains were inoculated in MRS broth and agar plate where 100 ppm of Pb(NO3)2 and CdSO4 were added, respectively. They did grow in the conditions and we found aggregations from 24 h cultures, indicating the strains can absorb the heavy metals, which was further proved by scanning electron microscopy (SEM) and Inductively Coupled Plasma-Optical Emission Spectrometer. Therefore the isolated lactic acid bacteria can be used as a probiotics harboring heavy metal scavenging activity.

In order to investigate novel insect growth regulators (IGRs) from actinomycetes, 363 isolates of actinomycetes were tested for their IGR activities. Among them, Streptomyces sp. AN120537 showed the highest juvenile hormone antagonist (JHAN) activity and significant insecticidal activities against larvae of Aedes albopictus and Plutella xylostella. In addition, the dead larvae showed morphological deformities such as contraction of body segments or pigmentation of all body parts. Through liquid chromatography and bioassay-guided fractionation, 7 IGR compounds were identified from the crude hexane extract of AN120537. These results suggested that Streptomyces sp. AN120537 could be useful resources for development of eco-friendly insecticidal agents.

The objective of this study is to investigate the earthquake response for the design of 100m spanned single-layer lattice dome. The plastic hinge analysis and eigenvalue buckling analysis are performed to estimate the ultimate load of single-layered lattice domes under vertical loads. In order to ensure the stability of lattice domes, it is investigated for the plastic hinge progressive status by the pushover increment analysis considering the elasto-plastic connection. One of the most effective methods to reduce the earthquake response of large span domes is to install the LRB isolation system of a dome. The authors discuss the reducing effect for the earthquake dynamic response of 100m spanned single-layered lattice domes. The LRB seismic isolation system can greatly reduce the dynamic response of lattice domes for the horizontal and vertical earthquake ground motion.

To date, there are no protocols optimized to the effective separation of spermatogonial stem cells (SSCs) from testicular cells derived from mouse testes, thus hindering studies based on mouse SSCs. In this study, we aimed to determine the most efficient purification method for the isolation of SSCs from mouse testes among previously described techniques. Isolation of SSCs from testicular cells derived from mouse testes was conducted using four different techniques: differential plating (DP), magnetic-activated cell sorting (MACS) post-DP, MACS, and positive and negative selection double MACS. DP was performed for 1, 2, 4, 8, or 16 h, and MACS was performed using EpCAM (MACSEpCAM), Thy1 (MACSThy1), or GFR α1 (MACSGFRα1) antibodies. The purification efficiency of each method was analyzed by measuring the percentage of cells that stained positively for alkaline phosphatase. DP for 8 h, MACSThy1 post-DP for 8 h, MACSGFRα1, positive selection double MACSGFRα1/EpCAM, and negative selection double MACSGFRα1/α-SMA were identified as the optimal protocols for isolation of SSCs from mouse testicular cells. Comparison of the purification efficiencies of the optimized isolation protocols showed that, numerically, the highest purification efficiency was obtained using MACSGFRα1. Overall, our results indicate that MACSGFRα1 is an appropriate purification technique for the isolation of SSCs from mouse testicular cells.

Seismic isolation systems have typically been used in the form of base seams in mid-rise and low-rise buildings. In the case of high-rise buildings, it is difficult to apply the base isolation. In this study, the seismic response was analyzed by changing the installation position of the seismic isolation device in 3D high - rise model. To do this, we used 30-story and 40-story 3D buildings as example structures. Historic earthquakes such as Mexico (1985), Northridge (1994) and Rome Frieta (1989) were applied as earthquake loads. The installation position of the isolation device was changed from floor to floor to floor. The maximum deformation of the seismic isolation system was analyzed and the maximum interlaminar strain and maximum absolute acceleration were analyzed by comparing the LB model with seismic isolation device and the Fixed model, which is the base model without seismic isolation device. If an isolation device is installed on the lower layer, it is most effective in response reduction, but since the structure may become unstable, it is effective to apply it to an effective high-level part. Therefore, engineers must consider both structural efficiency and safety when designing a mid-level isolation system for high-rise buildings.

최근에는 다양한 중량의 구조물을 지진으로부터 보호하기 위해 지반으로부터 분리하는 면진장치로써 지반 격리용 받침이 활용된다. 지진의 피해를 저감시키는 설계방법 중에서 면진 설계는 구조물과 지반이 만나는 부분에 면진받침을 사용하는 방식으로 다른 내진/제진 설계 방법과 비교하면 가격대비 효율과 성능이 가장 우수하다. 본 연구에서는 지진 발생 이후 지속적으로 사용 가능한 새로운 개념의 자동복원 면진받침 시스템을 제안하고자 한다. 이러한 면진받침에 대한 성능을 검증하기 위하여 이론 적립 및 설계를 수행하고 실험체를 제작하여 실제 지진 데이터가 적용된 진동대 실험을 수행하였다. 기본특성실험, 면압의존성 실험, 속도의존성 실험, 변위의존성 실험에서 강도하중이 설계 목표치와 유사하였고, 거동 또한 설계값과 유사함을 확인하였고 이를 바탕으로 면진받침의 성능 검증을 분석하였다.

Because the pig is a valuable candidate for a preclinical model of human cell therapy as well as an important food source, understanding a physiology of pig myogenic progenitors such as skeletal muscle satellite cells and myoblasts is required for cure of muscular diseases and improvement of meat production. For these reasons, we tried to isolate and culture the pig progenitor cells from skeletal muscle. Pig satellite cells, known as muscle stem cells, were isolated from biceps femoris of neonatal pigs by enzymatic digestion method. Muscle satellite cells are quiescent in uninjured muscle. Upon injury, they are activated into proliferating state, known as myoblasts, by growth factors and, in turn, differentiated forward to myocytes and myotubes. To trigger proliferation in vitro, the isolated satellite cells were cultured with epidermal growth factor (EGF) and dexamethasone (BMP4 inhibitor). As a result, the pig satellite cells were efficiently converted into proliferating myoblasts and stably maintained over an extended period. The myoblasts were confirmed by markers of PAX7, MYF5, and MYOD1. Our finding showed that modulating EGF and BMP4 signaling are essential for maintaining muscle stem cells. This culture method could be applied for a production of cultured meat and further basic research of muscle development. This work was supported by the Korea Institute of Planning and Evaluation for Technology in food, agriculture, forestry, and fisheries (IPET) through the Development of High Value-Added Food Technology Program funded by the Ministry of Agriculture, Food, and Rural Affairs (MAFRA; 118042-03-1-HD020).

블루베리혹파리(Dasineura oxycoccana)는 우리나라에서 2010년에 처음 발견된 이래로 지금은 전국의 블루베리 재배지에서 발견되고 있는 외래해충이다. 이 해충의 생태 조사와 방제 연구를 위해 효과적인 유인제 개발이 필요한 실정이다. 비록 캐나다 개체군으로부터 이 해충의 암컷 성페로몬이 이미 보고되었을지라도, 캐나다 연구자들은 이 물질의 질량 스펙트럼이 아닌 기체크로마토그래피의 머무름 시간 비교를 통해 성페로몬을 동정하고 야외 유인시험을 통해 확인하였다. 우리는 블루베리혹파리 유인제 개발의 첫 단계로서 이 종의 성페로몬을 암컷으로부터 분리하여 천연 물질의 질량 스펙트럼을 확인하는 것을 목표로 하였다. 암컷 성충 21마리의 복부 추출물을 농축한 시료 속에서 이 종의 성페로몬으로 알려진 ‘2,14-diacetoxy heptadecane’을 성공적으로 분리하였다. 한편, 암컷 성페로몬의 부성분으로 추정할 수 있는 추가적인 유사물질은 발견되지 않았다

The objective of this study is to investigate the response reducing effect of a seismic isolation system installed between 300m dome and supports under both horizontal and vertical seismic ground motion. The time history analysis is performed to investigate the dynamic behavior of single layer lattice domes with and without a lead rubber bearing seismic isolation system. In order to ensure the seismic performance of lattice domes against strong earthquakes, it is important to investigate the mechanical characteristics of dynamic response. Horizontal and vertical seismic ground motions cause a large asymmetric vertical response of large span domes. One of the most effective methods to reduce the dynamic response is to install a seismic isolation system for observing seismic ground motion at the base of the dome. This paper discusses the dynamic response characteristics of 300m single layer lattice domes supported on a lead rubber seismic isolation device under horizontal and vertical seismic ground motions.

A base isolation system is widely used to reduce seismic responses of low-rise buildings. This system cannot be effectively applied to high-rise buildings because the initial stiffness of the high-rise building with the base isolation system maintains almost the same as the building without the base isolation system to set the yield shear force of the base isolation system larger than the design wind load. To solve this problem, the mid-story isolation system was proposed and applied to many buildings. The mid-story isolation system has two major objectives; first to reduce peak story drift and second to reduce peak drift of the isolation story. Usually, these two objectives are in conflict. In this study, a hybrid mid-story isolation system for a tall building is proposed. A MR (magnetorheological) damper was used to develop the hybrid mid-story isolation system. An existing building with mid-story isolation system, that is “Shiodome Sumitomo Building” a high rise building having a large atrium in the lower levels, was used for control performance evaluation of the hybrid mid-story isolation system. Fuzzy logic controller and genetic algorithm were used to develop the control algorithm for the hybrid mid-story isolation system. It can be seen from analytical results that the hybrid mid-story isolation system can provide better control performance than the ordinary mid-story isolation system and the design process developed in this study is useful for preliminary design of the hybrid mid-story isolation system for a tall building.

Mycoplasma spp. are extracellular bacteria that colonize on the respiratory epithelium of humans and animals. It is a causative agent of pneumonia commonly complicated by opportunistic infectious bacteria. Mycoplasma spp. infection cause relatively mild disease in the absence of environmental stressors, but when complicated by secondary bacterial invaders the resultant disease can cause obvious clinical disease and severe production losses in intensively reared pigs Mycoplasma spp. are highly fastidious bacteria, difficult to culture and slow growing. Many species of Mycoplasma spp. are important pathogens causing respiratory infection in animals and known to induce huge economic losses. The aims of the present study were to develop a rapid isolation and culture method of wild type Mycoplasma spp. in pigs. We used Mycoplasma spp. genus specific direct PCR without DNA extraction procedure using PhireⓇ Animal Tissue Direct PCR Kit from the lung tissues with pneumonia lesions. Therefore, we could save the time for tissue processing and increase the accuracy of Mycoplasma spp. inclusion prediction in lung tissues. Thereafter, we used the optimized media to isolate and culture Mycoplasma spp. As the results, Mycoplasma spp. could be isolated and cultured quickly and efficiently. These results could provide an efficient strategy and method for the rapid and accurate isolation and culture of wild type Mycoplasma spp. in pigs.

Since the 2010 year, an occurring number of grand scale earthquakes which above magnitude 5.0 have increased in the world. Many types of research that deal with reducing the damage to the structure from a large-scale earthquake have proceeded. A system which could mitigate strong vertical earthquake's acceleration might apply to structure, since big earthquake cases that occurred lots of loss in Tokyo and Kobe of Japan. A plenty of bearings have installed to mitigate vibration but many parts of these lack efficient ability what we want. In addition, former vertical isolation bearings to apply for the structure have both price and size limits according to material characteristics. Therefore, this paper proposes a new type of device that is made by utilized engineering plastic and improves hitherto used vertical isolation bearing's fault.

As the number of high-rise buildings increases, a mid-story isolation system has been proposed for high-rise buildings. Due to structural problems, an appropriate isolation layer displacement is required for an isolation system. In this study, the mid-story isolation system was designed and the seismic response of the structure was investigated by varying the yield strength and the horizontal stiffness of the seismic isolation system. To do this, a model with an isolation layer at the bottom of 15th floor of a 20-story building was used as an example structure. Kobe(1995) and Nihonkai-Chubu(1983) earthquake are used as earthquake excitations. The yield strength and the horizontal stiffness of the seismic isolation system were varied to determine the seismic displacement and the story drift ratio of the structure. Based on the analytical results, as the yield strength and horizontal stiffness increase, the displacement of the isolation layer decreases. The story drift ratio decreases and then increases. The displacement of the isolation layer and the story drift ratio are inversely proportional. Increasing the displacement of the isolation layer to reduce the story drift ratio can cause the structure to become unstable. Therefore, an engineer should choose the appropriate yield strength and horizontal stiffness in consideration of the safety and efficiency of the structure when a mid-story isolation system for a high-rise building is designed.

In order to reduce the seismic response of the spatial structure, a seismic isolation system with sufficient flexibility is used. The natural period of structure with seismic isolation system got be long to avoid prominent period. In this study, The seismic response of the truss-arch structure, which is modeled in three types according to the rise-span ratio is analyzed on El-centro, Northridge and Artificial Earthquake and compared with the seismic response of the truss-arch structure with lead rubber bearing(LRB). When seismic load is applied to the truss arch with isolation system, the horizontal acceleration response of the truss arch is reduced and vertical seismic response is also reduced. The application of the seismic isolation system is effective in controlling the seismic response.