• Title/Summary/Keyword: base-isolated

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Interference effects in a group of tall buildings closely arranged in an L- or T-shaped pattern

  • Zhao, J.G.;Lam, K.M.
    • Wind and Structures
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    • v.11 no.1
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    • pp.1-18
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    • 2008
  • Interference effects in five square tall buildings arranged in an L- or T-shaped pattern are investigated in the wind tunnel. Mean and fluctuating shear forces, overturning moments and torsional moment are measured on each building with a force balance mounted at its base. Results are obtained at two values of clear separation between adjacent buildings, at half and a quarter building breadth. It is found that strong interference effect exists on all member buildings, resulting in significant modifications of wind loads as compared with the isolated single building case. Sheltering effect is observed on wind loads acting along the direction of an arm of the "L" or "T" on the inner buildings. However, increase in these wind loads from the isolated single building case is found on the most upwind edge building in the arm when wind blows at a slight oblique angle to the arm. The corner formed by two arms of buildings results in some wind catchment effect leading to increased wind pressure on windward building faces. Interesting interference phenomena such as negative drag force are reported. Interference effects on wind load fluctuations, load spectra and dynamic building responses are also studied and discussed.

Draft genome sequence of oligosaccharide producing Leuconostoc lactis CCK940 isolated from kimchi in Korea (올리고당을 생산하는 Leuconostoc lactis CCK940 균주의 유전체 염기서열)

  • Lee, Sulhee;Park, Young-Seo
    • Korean Journal of Microbiology
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    • v.54 no.4
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    • pp.445-447
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    • 2018
  • Leuconostoc lactis CCK940, which was isolated from kimchi obtained from a Korean traditional market, produced an oligosaccharide with a degree of polymerization of more than 4. In this study, the draft genome sequence of L. lactis CCK940 was reported by using PacBio 20 kb platform. The genome of this strain was sequenced and the genome assembly revealed 2 contigs. The genome was 1,741,511 base pairs in size with a G + C content of 43.33%, containing 1,698 coding sequences, 12 rRNA genes, and 68 tRNA genes. L. lactis CCK940 contained genes encoding glycosyltransferase, sucrose phosphorylase, maltose phosphorylase, and ${\beta}$-galactosidase which could synthesize oligosaccharide.

Complete genome sequence of Limosilactobacillus fermentum JNU532 as a probiotic candidate for the functional food and feed supplements

  • Bogun Kim;Ziayo Meng;Xiaoyue Xu;Seungwoo Baek;Duleepa Pathiraja;In-Geol Choi;Sejong Oh
    • Journal of Animal Science and Technology
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    • v.65 no.1
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    • pp.271-274
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    • 2023
  • Lactic acid bacteria (LAB) have been reported to possess various beneficial properties and are commonly used as probiotics. LAB play a crucial role in milk fermentation, industrial lactic acid fermentation, and health and medicine. Limosilactobacillus fermentum isolated from fermented dairy and food products is considered as 'Generally Recognized as Safe' by FDA. Limosilactobacillus fermentum plays an important role in modulation of the intestinal microbiota, enhancing the host immune system and improving feed digestibility. We isolated a probiotic candidate that was identified and named Limosilactobacillus fermentum JNU532. In a previous report, cell-free culture of L. fermentum JNU532 exhibited anti-melanogenic and antioxidant activities. In this study, we present the complete genome assembly of the bacterial strain JNU532. The final genome consists of one circular chromosome (2,077,416 base pairs) with a guanine + cytosine (GC) ratio of 51.5%.

Seismic responses of structure isolated by FPB subject to pounding between the sliding interfaces considering soil-structure interaction

  • Yingna Li;Jingcai Zhang
    • Earthquakes and Structures
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    • v.26 no.6
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    • pp.463-475
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    • 2024
  • The study aims to investigate the pounding that occurs between the isolator's ring and slider of isolated structures resulting from excessive seismic excitation, while considering soil-structure interaction. The dynamic responses and poundings of structures subjected a series seismic records were comparatively analyzed for three different soil types and fixed-base structures. A series of parametric studies were conducted to thoroughly discuss the effects of the impact displacement ratio, the FPB friction coefficient ratio, and the radius ratio on the structural dynamic response when considering impact and SSI. It was found that the pounding is extremely brief, with an exceptionally large pounding force generated by impact, resulting in significant acceleration pulse. The acceleration and inter-story shear force of the structure experiencing pounding were greater than those without considering pounding. Sudden changes in the inter-story shear force between the first and second floors of the structure were also observed. The dynamic response of structures in soft ground was significantly lower than that of structures in other ground conditions under the same conditions, regardless of the earthquake wave exciting the structure. When the structure is influenced by pulse-type earthquake records, its dynamic response exhibits a trend of first intensifying and then weakening as the equivalent radius ratio and friction coefficient ratio increase. However, it increases with an increase in the pounding displacement ratio, equivalent radius ratio, friction coefficient ratio, and displacement ratio when the structures are subjected to non-pulse-type seismic record.

Complete genome sequence of Treponema pedis GNW45 isolated from dairy cattle with active bovine digital dermatitis in Korea

  • Hector Espiritu;Lovelia Mamuad;Edeneil Jerome Valete;Sang-Suk Lee;Yong-Il Cho
    • Journal of Animal Science and Technology
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    • v.66 no.5
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    • pp.1079-1082
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    • 2024
  • Treponema pedis, a fastidious anaerobic spirochete, is one of the main pathogens involved in the development and progression of bovine digital dermatitis (BDD), a lameness-causing hoof infection in cattle. Here, the complete genome sequencing of T. pedis GNW45 isolated from a dairy cow infected with BDD, was presented. Libraries for long and short reads were sequenced using PacBioRSII and Illimuna HiSeqXTen platforms, respectively. De-novo assembly was done using the long reads, producing a circular contig, by which the short reads were aligned to generate a more accurate genome sequence. The genome has a total size of 3,077,465 base pairs, with 36.84% guanine-cytosine content. A total of 2,749 protein-coding sequences, seven ribosomal RNA's, and 45 transfer RNA's were annotated. Functional analysis revealed genes associated with pathogenicity and survivability in the complex pathobiome of BDD. This study provided novel insights into the survival and pathogenic mechanisms of T. pedis GNW45.

Base Isolation of the 1/3 Scaled RC Building with the Laminated Rubber Bearings (적층고무형 면진 장치를 갖는 철근콘크리트 건물의 면진 특성)

  • Chang Kug-Kwan;Chun Young-Soo;Kim Dong-Young
    • Journal of the Korea Concrete Institute
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    • v.17 no.6 s.90
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    • pp.975-982
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    • 2005
  • Scientific community agrees about the fact that base Isolation provides interesting solutions to minimize the seismic risk. Reliability of such a technique is nowadays proofed by a large number of applications like public buildings, nuclear plants, bridges, etc. This paper reports the results of performance verification tests of the base isolated RC building with the laminated rubber bearings which is manufactured by enterprise in Korea. The shaking table tests were performed using a three story model scaled to 1/3 of the prototype RC apartment building. Several major earthquake records were scaled to different peak ground accelerations and used as input base excitations. Especially in this study, effect of earthquake characteristics on response reduction and effect of the intensity of excitations are studied. Through the verification tests, the validity of the applied base isolaion device and the response reduction effect against earthquakes are confirmed.

Characterization of a Recombinant Thermostable Arylsulfatase from Deep-Sea Bacterium Flammeovirga pacifica

  • Gao, Chao;Jin, Min;Yi, Zhiwei;Zeng, Runying
    • Journal of Microbiology and Biotechnology
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    • v.25 no.11
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    • pp.1894-1901
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    • 2015
  • A novel sulfatase gene, ary423 (1,536 bp ORF), encoding a protein of 511 amino acids with a calculated molecular mass of 56 kDa, was identified from Flammeovirga pacifica, which was isolated from deep-sea sediments of west Pacific Ocean. Amino acid sequence analysis revealed that Ary423 possessed a conserved C-X-A-X-R motif, which was recognized as the sulfatase signature. Phylogenetic analysis suggested that Ary423 belonged to arylsulfatases. After heterologous expression in Escherichia coli cells, the recombinant Ary423 was purified with a Ni+ affinity column, and was shown to be highly active at a broad range of temperatures from 30° to 70℃, with maximum activity at 40℃. Furthermore, recombinant Ary423 retained more than 70% and 40% of its maximum activity after 12 h of incubation at 50℃ and 60℃, respectively, exhibiting good thermostability at high temperatures. The optimal pH for Ary423 was determined to be 8.0 and the activity of Ary423 could be slightly enhanced by Mg2+. The recombinant enzyme could hydrolyze sulfate ester bonds in p-nitrophenyl sulfate (NPS) and Asparagus crude polysaccharides with a specific activity of 64.8 U/mg and 25.4 U/mg, respectively. These favorable properties could make Ary423 attractive for application in the desulfating process of agar production.

Base Isolation Performance of Friction Pendulum System using Magnetic Force (자력을 이용한 마찰진자 베어링의 면진성능)

  • Hwang, In-Ho;Shin, Ho-Jae;Lee, Jong-Seh
    • Journal of the Earthquake Engineering Society of Korea
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    • v.12 no.4
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    • pp.55-61
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    • 2008
  • One of the most recent base-isolation systems to improve the earthquake resistance of structures is the Friction Pendulum System(FPS). Simple in design but with versatile properties, the FPS has been used in some of the world s largest seismically isolated buildings, bridges and chemical tanks. FPS using PTFE(Polytetrafl-uoroethylene) based material has been developed to provide a simple and effective way for structures to achieve earthquake resistance. PTFE materials are soft, and are apt to become deformed easily after a few working cycles. In this study, magnetic force is used rather than the usual PTFE materials to improve the material shortcomings. A MF-FPS(Magnetic force-Friction Pendulum System) is proposed, and us shown to effectively protect structures against earthquakes. To demonstrate the advantages of this new system, the MF-FPS is compared with FPS as an attempt to prove its performance. A six-degree-of-freedom model is considered as a numerical example. The ground acceleration data of El Centro, Mexico and Gebze earthquakes are used as seismic excitations. The results showed that MF-FPS improved performance compared with FPS.

Variability of Stem-Base Infestation and Coexistence of Fusarium spp. Causing Crown Rot of Winter Wheat in Serbia

  • Jevtic, Radivoje;Stosic, Nemanja;Zupunski, Vesna;Lalosevic, Mirjana;Orbovic, Branka
    • The Plant Pathology Journal
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    • v.35 no.6
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    • pp.553-563
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    • 2019
  • Investigations related with factors influencing root and crown rot are rare and mainly related to farming practice and soil management. The main objective of this study was to examine broader range of factors influencing stem-base infestation of winter wheat in the field conditions. The effect of spatial distribution of infected plants on disease index (DIs) assessments was also investigated. Analysis of factors influencing DIs of crown rot of wheat demonstrated significant influence of the growing seasons (P < 0.001) and extreme fluctuations in winter temperatures (P < 0.001). In addition to that, localities together with their interaction with the growing season also significantly influenced DIs (P < 0.001). Aggregation of infected plants influenced variability of DI estimations, and it was pointed out that more extensive investigation should be conducted on broad range of DI in order to establish sampling method giving uniform sampling precision. Fusarium graminearum was shown to be predominant Fusarium species in Serbia (72.6%) using sequence-characterized amplified region analysis. Interestingly F. oxysporum was isolated in higher frequencies (27.4%) than it was reported in the literature. Given that there were no reports on the diversity of Fusarium species causing crown rot of wheat in Serbia, this study presents first report on this important subject. It also indicated that more attention should be focused on combined effects of abiotic and biotic factors influencing stem-base infestation of winter wheat. This knowledge will contribute to better understanding of factors influencing root and crown rot of wheat which would ensure sustainable disease management in the future.

Seismic Fragility Analysis of Base Isolated NPP Piping Systems (지진격리된 원전배관의 지진취약도 분석)

  • Jeon, Bub Gyu;Choi, Hyoung Suk;Hahm, Dae Gi;Kim, Nam Sik
    • Journal of the Earthquake Engineering Society of Korea
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    • v.19 no.1
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    • pp.29-36
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    • 2015
  • Base isolation is considered as a seismic protective system in the design of next generation Nuclear Power Plants (NPPs). If seismic isolation devices are installed in nuclear power plants then the safety under a seismic load of the power plant may be improved. However, with respect to some equipment, seismic risk may increase because displacement may become greater than before the installation of a seismic isolation device. Therefore, it is estimated to be necessary to select equipment in which the seismic risk increases due to an increase in the displacement by the installation of a seismic isolation device, and to perform research on the seismic performance of each piece of equipment. In this study, modified NRC-BNL benchmark models were used for seismic analysis. The numerical models include representations of isolation devices. In order to validate the numerical piping system model and to define the failure mode, a quasi-static loading test was conducted on the piping components before the analysis procedures. The fragility analysis was performed by using the results of the inelastic seismic response analysis. Inelastic seismic response analysis was carried out by using the shell finite element model of a piping system considering internal pressure. The implicit method was used for the direct integration time history analysis. In addition, the collapse load point was used for the failure mode for the fragility analysis.