• 한국자원식물학회지
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• 제16권3호
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• pp.238-244
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• 2003

더덕 뿌리에서 유래한 EST 라이브러리로부터 dehydrin 유전자와 높은 상동성 을 나타내는 full clone cDNA를 얻었다. 더덕의 dehydrin, ClDhn1은 893 bp의 cDNA로 159개의 아미노산을 코딩하는 480 bp의 ORF를 가지고 있다. ClDhn1의 아미노산을 분석해 보면, 전체적으로 높은 친수성을 나타내며, lysine이 풍부한 K 반복구간(KIKEKLPG)을 카르보닐기 쪽에 2개 가지고 있다. 또한, 여러 dehydrin들의 공통적인 특징인 7개의 연속적인 serine잔기가 첫 번째 K반복 구간 앞에 위치한다. 그러나, 아미노기쪽의 DEYGNP보존 구간은 변형(DEHGNP)되어 있다. ClDhn1 유전자는 전사 단계에서 더덕의 뿌리에서 가장 높은 발현 양상을 보이며, 줄기와 잎에서는 적은 양이 발현되었다.

• The Plant Pathology Journal
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• 제17권6호
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• pp.375.3-375
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• 2001

• Computers and Concrete
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• 제11권2호
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• pp.169-182
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• 2013

One of the major benefits of the pre-stressed concrete pavements is the omission of tension in concrete that results in a reduction of cracks in the concrete slabs. Therefore, the life of the pavement is increased as the thickness of the slabs is reduced. One of the most important issues in dealing with the prestressed concrete pavement is determination of the magnitude of the pre-stress. Three dimensional finite element analyses are conducted in this research to study the pre-stress under various load (Boeing 777) and thermal gradient combinations. The model was also analyzed under temperature gradients without the presence of traffic loading and the induced stresses were compared with those from theoretical relationships. It was seen that the theoretical relationships result in conservative values for the stress.

• Structural Engineering and Mechanics
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• 제39권3호
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• pp.303-316
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• 2011

Experimental tests have shown that glass exhibits very different strengths when tested under biaxial and uniaxial conditions. This paper presents a study on the effects of biaxial stresses on the notional ultimate strength of glass. The study involved applying the theory of elasticity and finite element analysis of the Griffith flaw in the micro scale. The strain intensity at the tip of the critical flaw is used as the main criterion for defining the limit state of fracture in glass. A simple and robust relationship between the maximum principal stress and the uniaxial stress to cause failure of the same glass specimen has been developed. The relationship has been used for evaluating the strength values of both new and old annealed glass panels. The characteristic strength values determined in accordance with the test results based on 5% of exceedance are compared with provisions in the ASTM standard.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2008년도 춘계 학술발표회 초청강연 및 논문집
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• pp.505-510
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• 2008

FBG Sensor, which is smaller than strain gauge and has better durability and does not have a noise from electromagnetic waves, was adapted to develope a smart anchor. A series of pullout tests were performed to verify the feasibility of smart anchor and find out the load transfer mechanism around the steel wire fixed to rock with grout. Distribution of shear stresses at steel wire-grout interface is assessed from the measured strain distribution by the optical fiber sensors and compared with stress distributions predicted by Farmer's and Aydan's formulas. It was found that present theoretical formulas may underestimate the failure depth and magnitude of shear stresses when the pullout loads increase.

• Journal of Microbiology and Biotechnology
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• 제33권9호
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• pp.1119-1129
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• 2023

Seeds are colonized by diverse microorganisms that can improve the growth and stress resistance of host plants. Although understanding the mechanisms of plant endophyte-host plant interactions is increasing, much of this knowledge does not come from seed endophytes, particularly under environmental stress that the plant host grows to face, including biotic (e.g., pathogens, herbivores and insects) and abiotic factors (e.g., drought, heavy metals and salt). In this article, we first provided a framework for the assembly and function of seed endophytes and discussed the sources and assembly process of seed endophytes. Following that, we reviewed the impact of environmental factors on the assembly of seed endophytes. Lastly, we explored recent advances in the growth promotion and stress resistance enhancement of plants, functioning by seed endophytes under various biotic and abiotic stressors.

• Journal of Microbiology and Biotechnology
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• 제21권8호
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• pp.830-837
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• 2011

A genomic DNA fragment encoding a putative maltooligosyltrehalose trehalohydrolase (NfMTH) for trehalose biosynthesis was cloned by the degenerate primer- PCR from cyanobacterium Nostoc flagelliforme. The ORF of NfMTH is 1,848 bp in length and encodes 615 amino acid residues, constituting a 70 kDa protein. The deduced amino acid sequence of NfMTH contains 4 regions highly conserved for MTHs. By expression of NfMTH in E. coli, the function of this protein was demonstrated, where the recombinant protein catalyzed the hydrolysis of maltooligosyl trehalose to trehalose. The expressions of MTH and maltooligosyltrehalose synthase in the filaments of N. flagelliforme were upregulated significantly under dehydration stress, NaCl stress, and high temperature-drought stress. The accumulations of both trehalose and sucrose in the filaments of N. flagelliforme were also improved significantly under the above stresses. Furthermore, trehalose accumulated in smaller quantities than sucrose did when under NaCl stress, but accumulated in higher quantities than sucrose did when under temperature-drought stress, indicating that both trehalose and sucrose were involved in N. flagelliforme adapted to stresses and different strategies conducted in response to various stress conditions.

• Structural Engineering and Mechanics
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• 제86권2호
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• pp.167-180
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• 2023

This work applies a four-known quasi-3D shear deformation theory to investigate the bending behavior of a functionally graded plate resting on a viscoelastic foundation and subjected to hygro-thermo-mechanical loading. The theory utilizes a hyperbolic shape function to predict the transverse shear stress, and the transverse stretching effect of the plate is considered. The principle of virtual displacement is applied to obtain the governing differential equations, and the Navier method, which comprises an exponential term, is used to obtain the solution. Novel to the current study, the impact of the viscoelastic foundation model, which includes a time-dependent viscosity parameter in addition to Winkler's and Pasternak parameters, is carefully investigated. Numerical examples are presented to validate the theory. A parametric study is conducted to study the effect of the damping coefficient, the linear and nonlinear loadings, the power-law index, and the plate width-tothickness ratio on the plate bending response. The results show that the presence of the viscoelastic foundation causes an 18% decrease in the plate deflection and about a 10% increase in transverse shear stresses under both linear and nonlinear loading conditions. Additionally, nonlinear loading causes a one-and-a-half times increase in horizontal stresses and a nearly two-times increase in normal transverse stresses compared to linear loading. Based on the article's findings, it can be concluded that the viscosity effect plays a significant role in the bending response of plates in hygrothermal environments. Hence it shall be considered in the design.

• 미생물과산업
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• 제26권2호
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• pp.32-40
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• 2000

• Asian-Australasian Journal of Animal Sciences
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• 제5권3호
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• pp.401-409
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• 1992

Genotype $\times$ environment (G $\times$ E) interactions must be understood if they are to be exploited to improve animal production, particularly in production systems associated with large environmental variations. The measurement and evaluation of G $\times$ E are discussed. Examples are presented that demonstrate G $\times$ E in different breeds of beef cattle for high temperatures, internal and external parasites and changes in quantity and quality of nutrition. It is demonstrated that productivity differences between genotypes or breeds under grazing conditions arise because of differences between genotypes in the combination of production potential and resistance to environmental stresses in relation to the levels of the relevant environmental stresses that are operating at the time. The $F_1$ cross between genotypes with high production potential (e.g. European Bos Taurus breeds) and those with high resistance to environmental stress (e.g. Asian and African Bos indicus and sanga breeds) is an exceptional genotype with a unique combination of these two sets of attributes. The principles for G $\times$ E developed for beef cattle are briefly discussed in relation to dairy cattle, pigs, poultry and buffalo.