• 한국식품과학회지
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• 제54권2호
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• pp.179-184
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• 2022

본 연구에서는 열 압착 공정을 이용하여 생고분자 가식성 FG 필름과 MG 필름을 제작하였고, 제조 공정 차이에 따른 필름의 형성, 표면 미세구조, 그리고 빛 투과도를 비교하기 위해 캐스팅 방법을 이용해서도 FG 필름을 제작하였다. 열 압착을 이용하여 FG와 MG로부터 연속적이고, 균일하며, 투명하고, 그리고 매끄러운 표면을 가진 필름을 제작할 수 있었다. 열 압착된 FG 필름은 열 압착된 MG 필름보다 빛 투과도와 인장 강도가 낮았으나, 육안 관찰 및 현미경을 이용한 표면 미세구조를 관찰 시 큰 차이를 확인할 수 없었으며, 수분 투과도와 필름의 명도 및 붉은 정도에서도 유의적인 차이가 보이지 않았다. 또한, 열 압착된 FG 필름이 캐스팅된 FG 필름보다 육안으로 보았을 때 더욱 투명하고 균일한 표면을 가진 것을 확인할 수 있었고, 투명도도 캐스팅 된 FG 필름보다 높음을 알 수 있었다. 열 압착된 FG 필름이 캐스팅된 FG 필름보다 낮은 인장 강도와 높은 수분 차단 능력을 갖췄다. 열 압착된 FG 필름은 캐스팅된 FG 필름과 색도의 차이가 있었고, 캐스팅된 FG 필름보다 매끄럽고 균일한 표면 미세구조를 가진 것을 알 수 있었다. 본 연구의 결과는 열 압착 공정을 사용하는 산업적 생고분자 생산 시스템을 사용하여 우수한 수분 차단 능력을 갖춘 가식성 필름을 MG과 생선껍질로부터 얻어지는 FG을 이용해 제작할 수 있음을 보여주었다.

• Structural Engineering and Mechanics
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• 제64권1호
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• pp.121-133
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• 2017

This paper proposes an analytical solution method for free vibration of curved functionally graded (FG) nonlocal beam supposed to different thermal loadings, by considering porosity distribution via nonlocal elasticity theory for the first time. Material properties of curved FG beam are assumed to be temperature-dependent. Thermo-mechanical properties of porous FG curved beam are supposed to vary through the thickness direction of beam and are assumed to be temperature-dependent. Since variation of pores along the thickness direction influences the mechanical and physical properties, porosity play a key role in the mechanical response of curved FG structures. The rule of power-law is modified to consider influence of porosity according to even distribution. The governing equations of curved FG porous nanobeam under temperature field are derived via the energy method based on Timoshenko beam theory. An analytical Navier solution procedure is used to achieve the natural frequencies of porous FG curved nanobeam supposed to thermal loadings with simply supported boundary condition. The results for simpler states are confirmed with known data in the literature. The effects of various parameters such as nonlocality, porosity volume fractions, type of temperature rising, gradient index, opening angle and aspect ratio of curved FG porous nanobeam on the natural frequency are successfully discussed. It is concluded that these parameters play key roles on the dynamic behavior of porous FG curved nanobeam. Presented numerical results can serve as benchmarks for future analyses of curve FG nanobeam with porosity phases.

• Food Science and Biotechnology
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• 제16권6호
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• pp.999-1005
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• 2007

An oil-in-water (O/W) emulsion [20 wt% com oil, 0.5-6.0 wt% fish gelatin (FG), pH 3.0] was produced by high pressure homogenization, and the influence of pH, protein concentration, and homogenization condition on the formation of FG-stabilized emulsions was assessed by measuring particle size distribution, electrical charge, creaming stability, microstructure, and free FG concentration in the emulsions. Optical microscopy indicated that there were some large droplets ($d>10\;{\mu}m$) in all FG-emulsions, nevertheless, the amount of large droplets tended to decrease with increasing FG concentration. More than 90% of FG was present free in the continuous phase of the emulsions. To facilitate droplet disruption and prevent droplet coalescence within the homogenizer, homogenization time was adjusted in O/W emulsions stabilized by 2.0 or 4.0 wt% FG. However, the increase in the number of pass rather promoted droplet coalescence. This study has shown that the FG may have some limited use as a protein emulsifier in O/W emulsions.

• The Plant Pathology Journal
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• 제32권4호
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• pp.281-289
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• 2016

The transcription cofactor Swi6 plays important roles in regulating vegetative growth and meiosis in Saccharomyces cerevisiae. Functions of Swi6 ortholog were also characterized in Fusarium graminearum which is one of the devastating plant pathogenic fungi. Here, we report possible role of FgSwi6 in the interaction between F. graminearum and Fusarium graminearum virus 1 (FgV1) strain DK21. FgV1 perturbs biological characteristics of host fungi such as vegetative growth, sporulation, pigmentation, and reduction of the virulence (hypovirulence) of its fungal host. To characterize function(s) of FgSWI6 gene during FgV1 infection, targeted deletion, over-expression, and complementation mutants were generated and further infected successfully with FgV1. Deletion of FgSwi6 led to severe reduction of vegetative growth even aerial mycelia while over-expression did not affect any remarkable alteration of phenotype in virus-free isolates. Virus-infected (VI) FgSWI6 deletion isolate exhibited completely delayed vegetative growth. However, VI FgSWI6 over-expression mutant grew faster than any other VI isolates. To verify whether these different growth patterns in VI isolates, viral RNA quantification was carried out using qRT-PCR. Surprisingly, viral RNA accumulations in VI isolates were similar regardless of introduced mutations. These results provide evidence that FgSWI6 might play important role(s) in FgV1 induced phenotype alteration such as delayed vegetative growth.

• Steel and Composite Structures
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• 제44권4호
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• pp.451-471
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• 2022

In the present paper, the static bending and buckling responses of functionally graded carbon nanotubes-reinforced composite (FG-CNTRC) beam under various boundary conditions are investigated within the framework of higher shear deformation theory. The significant feature of the proposed theory is that it provides an accurate parabolic distribution of transverse shear stress through the thickness satisfying the traction-free boundary conditions needless of any shear correction factor. Uniform (UD) and four graded distributions of CNTs which are FG-O, FG-X, FG- and FG-V are selected here for the analysis. The effective material properties of FG-CNTRC beams are estimated according to the rule of mixture. To model the FG-CNTRC beam realistically, an efficient Hermite-Lagrangian finite element formulation is successfully developed. The accuracy and efficiency of the present model are demonstrated by comparison with published benchmark results. Moreover, comprehensive numerical results are presented and discussed in detail to investigate the effects of CNTs volume fraction, distribution patterns of CNTs, boundary conditions, and length-to-thickness ratio on the bending and buckling responses of FG-CNTRC beam. Several new referential results are also reported for the first time which will serve as a benchmark for future studies in a similar direction. It is concluded that the FG-X-CNTRC beam is the strongest beam that carries the lowest central deflection and is followed by the UD, V, Λ, and FG-O-CNTRC beam. Besides, the critical buckling load belonging to the FG-X-CNTRC beam is the highest, followed by UD and FG-O.

• Structural Engineering and Mechanics
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• 제78권2호
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• pp.135-143
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• 2021

In this study, continuous contact problem in the functionally graded (FG) layer loaded with a FG flat punch resting on the elastic semi-infinite plane was analyzed by the finite element method (FEM). It was assumed that the shear modulus and density of the layer and punch varied according to exponentially throughout their depth. FG layer's weight was included to the problem and additionally all surfaces were considered as frictionless. Analysis of FG materials was performed with a special macro which was added to the ANSYS program. Firstly, the shear modulus of the punch was considered to be very rigid and the results of initial separation load (λcr) and distance (xcr) were compared with the analytical solution. Afterwards, results obtained from the contact analysis made according to the inhomogeneity parameters (β, γ) between FG punch-FG layer which had been unprecedented in the literature were discussed. As a result, FG punch's stress values at the punch edges where stress accumulations occurred were found to be smaller than the rigid punch. The security of the structure, longer life of the material and ease of production are directly related to the reduction of the stress values. The results obtained in this study are important in this respect. Also this work is the first study that investigates the effect of FG punch on the FG layer.

• The Plant Pathology Journal
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• 제35권5호
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• pp.393-405
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• 2019

Survival factor 1 (Svf1) is a protein involved in cell survival pathways. In Saccharomyces cerevisiae, Svf1 is required for the diauxic growth shift and survival under stress conditions. In this study, we characterized the role of FgSvf1, the Svf1 homolog in the homothallic ascomycete fungus Fusarium graminearum. In the FgSvf1 deletion mutant, conidial germination was delayed, vegetative growth was reduced, and pathogenicity was completely abolished. Although the FgSvf1 deletion mutant produced perithecia, the normal maturation of ascospore was dismissed in deletion mutant. The FgSvf1 deletion mutant also showed reduced resistance to osmotic, fungicide, and cold stress and reduced sensitivity to oxidative stress when compared to the wild-type strain. In addition, we showed that FgSvf1 affects glycolysis, which results in the abnormal vegetative growth in the FgSvf1 deletion mutant. Further, intracellular reactive oxygen species (ROS) accumulated in the FgSvf1 deletion mutant, and this accumulated ROS might be related to the reduced sensitivity to oxidative stress and the reduced resistance to cold stress and fungicide stress. Overall, understanding the role of FgSvf1 in F. graminearum provides a new target to control F. graminearum infections in fields.

• 대한의용생체공학회:의공학회지
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• 제16권3호
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• pp.367-375
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• 1995

광범위 항생물질인 Ampicillin sodium(AMP-Na)을 두가지 방법 즉, 단순섞임과 bovine serum albumin(BSA)으로 microsphere화한 후 loading 하는 방법으로 fibrin glue(FG)를 제조하였고 이 FG로부터 AMP-Na의 서방성 시험을 시도하였다. 단순섞임의 경우 fibrinogen(FBNG)의 농도를 조적함으로서 FG로부터 AMP-Na의 지속적 방출을 달성할 수 있었으며 특히 이 microsphere를 glutaraldehyde로 가교화시킴으로서 용출속도를 더욱 늦출 수 있었다.(tO.9 : 33hr). FG의 rat perironeum에 대한 접착력은 FBNG과 thrombin의 농도가 각각 5.0%, 25~50 NIHU/ml에서 최대로 나타났다. Factor XIII의 농도는 0~500 U/1g of FBNG의 범위내에서 접착력에 거의 영향을 미치지 않았으며 incubation time은 60분일 때 최대로 나타났다. FG에 AMP-Na 및 BSA micorsphere를 loading하여도 접착력에는 큰 영향을 미치지 않았다.

• Asian-Australasian Journal of Animal Sciences
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• 제17권2호
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• pp.203-206
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• 2004

Fodder supply condition was studied at 41 nomadic families in Gobi, Southern Semi-Desert area in Mongolia, from Dec. 1994 to Apr. 1995 to determine problems in cold, feed deficient season for establishment of sustainable livestock production system. The conditions of two family groups: those located in sparse vegetation (FG1), and those in comparably dense (FG2), were also compared. Commercial concentrate feed (concentrate), hay and Zoodoi were prepared for supplementation. Zoodoi was hand-made feed made mainly of Allium mongolicum and Allium polyrrhizum. Allium mongolicum tended to be used at FG1 frequently, and Allium polyrrhizum at FG2 depend on differences of micro vegetation. 44%, 90% and 39% of families prepared 165.6 kg of concentrate, 301.6 kg of hay and 6.8 kg of Zoodoi per sheep and goat (small livestock) on the average, respectively. The ratio of families that used concentrate at FG1 was smaller than those at FG2, though there were no significant differences on the amount. More hay was fed at FG1 than at FG2, and Zoodoi tended to be fed more in the FG1 group. Recipients were mostly restricted to young, female and sick small livestock that use the feeds effectively. More families gave concentrate and hay to the young than to the females and sick. They also gave more Zoodoi to young and sick animals than to females in this area. In the FG1 group, no differences were found between recipients on the concentrate supply. More families supplied hay to young animals than to sick ones, and Zoodoi was fed more to sick animals than to young and females. On the other hand, those in the FG2 found, more families fed fodders to young than to female and sick regardless of the kinds of feeds. The amount of fodder supplementation in the studied area was restricted, but accurate techniques of nomads to adapt the situation were clarified.

• Animal Bioscience
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• 제34권4호
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• pp.584-593
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• 2021

Objective: The objective of this study was to compare fenugreek (FG) with alfalfa (Alf) in ruminal fermentation and methane (CH4) production in vitro. Methods: Whole-plant FG harvested at 11- and 15-wk and Alf harvested at early and mid-bloom maturities, alone or as 50:50 mixture of FG and Alf at the respective maturity, were assessed in a series of 48-h in vitro batch culture incubations. Total fermentation gas and methane gas production, dry matter (DM) disappearance, volatile fatty acids, microbial protein and 16S RNA gene copy numbers of total bacteria and methanogens were determined. Results: Compared to early bloom Alf, FG harvested at 11-wk exhibited higher (p<0.05) in vitro DM and neutral detergent fibre disappearance, but this difference was not observed between the mid-bloom Alf and 15-wk FG. Regardless plant maturity, in vitro ruminal fermentation of FG produced less (p<0.001) CH4 either on DM incubated or on DM disappeared basis than that of Alf during 48-h incubation. In vitro ruminal fermentation of FG yielded similar amount of total volatile fatty acids with higher (p<0.05) propionate percentage as compared to fermentation of Alf irrespective of plant maturity. Microbial protein synthesis was greater (p<0.001) with 11-wk FG than early bloom Alf as substrate and 16S RNA gene copies of total bacteria was higher (p<0.01) with 15-wk FG than mid-bloom Alf as substrate. Compared to mid-bloom Alf, 15-wk FG had lower (p<0.05 to 0.001) amount of 16S RNA methanogen gene copies in the whole culture during 48-h incubation. Conclusion: In comparison to Alf, FG emerges as a high quality forage that can not only improve rumen fermentation in vitro, but can also remarkably mitigate CH4 emissions likely due to being rich in saponins.