• 한국미생물·생명공학회지
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• 제47권3호
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• pp.372-380
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• 2019

Modern biotechnological industries have been attempting to improve the efficiency of bacterial strain cultivation. Millimeter wave electromagnetic radiation can have a varied influence on E. coli cultivation processes. The results of the study revealed that when a microwave radiation of low intensity is applied to positively adjust the conditions for the accumulation of bacterial culture biomass, a significant role is played not only by radiation parameters, but also by concomitant biological factors, which influence the reproducibility of the cultivation process and help obtain a useful biotechnological effect. The authors suggest a model that can be used to study the molecular mechanisms underlying the changes in the buildup of E. coli biomass under the influence of electromagnetic radiation.

• Geomechanics and Engineering
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• 제18권6호
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• pp.605-614
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• 2019

The present paper seeks to investigate propagation and reflection of waves at free surfaces of homogeneous, anisotropic and rotating micropolar fibre-reinforced medium with voids. It has been observed that, in particular when P-wave is incident on the free surface, there exist four coupled reflected plane waves traveling in the medium; quasi-longitudinal displacement (qLD) wave, quasi-transverse displacement (qTD) wave, quasi-transverse microrotational wave and a wave due to voids. Normal mode Analysis usually called harmonic solution method is adopted in concomitant with Snell's laws and appropriate boundary conditions in determination of solution to the micropolar fibre reinforced modelled problem. Amplitude ratios which correspond to reflected waves in vertical and horizontal components are presented analytically. Also, the Reflection Coefficients are presented using numerical simulated results in graphical form for a particular chosen material by the help of Mathematica software. We observed that the micropolar fibre-reinforced, voids and rotational parameters have various degrees of effects to the modulation, propagation and reflection of waves in the medium. The study would have impact to micropolar fibre-reinforecd rotational-acoustic machination fields and future works about behavior of seismic waves.

• Journal of the Korean Wood Science and Technology
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• 제50권6호
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• pp.436-447
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• 2022

Lignocellulose nanofibrils (LCNFs) were prepared using a two-step deep eutectic solvent (DES) and enzymatic pretreatment followed by mechanical defibrillation, and we examined the effects of enzymatic pretreatment conditions on different characteristics of the LCNFs thus obtained. The LCNFs yielded using the two-step DES pretreatment (Enz-LCNF) exhibited a well-defibrillated entangled web-like structure with an average fiber diameter ranging from 15.7 to 20.4 nm. Furthermore, we found that the average diameter and filtration time of the Enz-LCNFs decreased with an increase in enzyme concentration and enzymatic treatment time, whereas we detected a concomitant reduction in the tensile strength of the Enz-LCNF sheets. The Enz-LCNFs were characterized by a typical cellulose I structure, thereby indicating that the enzymatic treatment causes very little damage to the crystalline form.

• Journal of Forest and Environmental Science
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• 제38권4호
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• pp.290-301
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• 2022

Increasing life expectancy leads to a rise in the prevalence of aging-related mental diseases and a concomitant increase in the financial and societal pressures related to their prevention and management. This issue is attracting increasing attention from researchers. Therefore, this study aimed to determine whether a healing program in a forest environment is effective for improving cognitive function, depression, anxiety, and stress in elderly people. A nonequivalent control group pretest-posttest design was used. The experimental group consisted of 18 males and females aged 60 to 80 years who participated in a forest healing program for seven days, while the comparison group comprised 10 people with similar demographics. For the process of data analysis, this study performed a cross-analysis to determine the homogeneity of the data and carried out the Wilcoxon signed-rank test, a nonparametric statistical test, to verify the significance of each group. Participation in the forest healing program led to a significant improve-ment in cognitive function (p=0.030). The levels of depression decreased, but this result was not statistically significant. The levels of anxiety decreased significantly (p=0.004). The mean cortisol score, a measurement of stress, decreased, but it was not statistically significant. These findings confirmed the effectiveness of this program for improving certain mental conditions of elderly people, and affirmed that the use of long-term forest healing programs can be expected to alleviate national pressures created by aging societies.

• 분석과학
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• 제20권1호
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• pp.55-60
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• 2007

A sensitive technique for the determination of trace Cu(II) in various samples after the column preconcentration by adsorbing its N-benzoylphenylhydroxylamine (BPHA) onto benzophenone was developed. Several experimental conditions such as the pH of the sample solution, the amount of chelating agent, the amount of benzophenone, and the flowrate of sample solution and so forth were optimized. The interfering effects of diverse concomitant ions were investigated. Fe(III) and $CN^-$ interfered with more seriously than any other ions. However, the interference by these ions could be overcome sufficiently by adjusting the added volume of 0.01M BPHA to 10 mL. The dynamic range, the correlation coefficient ($r^2$) and the detection limit obtained by this proposed technique were 5.0~120 ng/mL, 0.9974, and 2.1 ng/mL, respectively. For validating this proposed technique, the aqueous samples (stream water, reservoir water, and wastewater), the plastic sample and the diluted brass sample were used. Recovery yields of 93~102% were obtained. These measured data were not different from ICP-MS data at 95% confidence level. This method was also validated by the rice flour CRM (normal, fortified) samples. Based on the results from the experiment, it was found that this proposed technique could be applied to the determination of Cu(II) in various real samples.

• Journal of Digestive Cancer Research
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• 제5권1호
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• pp.37-43
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• 2017

Laparoscopic cholecystectomy is of one the most common general surgical operations performed today. Concomitant choledocholithiasis occurs in roughly 10-20% of patients with symptomatic gallstones. Laparoscopic bile duct exploration (LBDE) offers a single-stage minimally-invasive solution to the management of choledocholithiasis. LBDE may be performed either via the transcystic route or via laparoscopic choledochotomy. A number of strategies to improve success are available to the surgeon to help in the problem of complicated choledocholithiasis, these range from simple maneuvers to the use of laser or mechanical lithotriptors. With the advances in laparoscopic surgery, it is also possible to handle complex surgical conditions such as Mirizzi syndrome or recurrent pyogenic cholangitis laparoscopically, even though these have yet to be accepted as standard of care. Following laparoscopic choledochotomy, options for closure include: primary closure, closure over a T-tube, and closure over an endobiliary stent. T-tube placement has been associated with increased operating time and hospital length of stay compared to primary closure, with no significant differences in morbidity. Based on the available literature, LBDE appears comparable to ERCP with regards to procedural efficacy and morbidity. LBDE remains relevant to the general surgeon and is best viewed as being complementary to endoscopic therapy in the management of choledocholithiasis.

• Journal of Microbiology and Biotechnology
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• 제25권7호
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• pp.1093-1100
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• 2015

Acetate and lactate in growth media are detrimental to the production of Thermus maltogenic amylase (ThMA), a heterologous protein, as well as to the growth of recombinant Escherichia coli. Only 50 mM of acetate or 10 mM of lactate reduced 90% of specific ThMA activity. In this study, mutant E. coli strains blocked in the ackA-pta or ackA-pta and ldh pathways were created, characterized, and assessed for their culture performace in 300 L-scale fermentation. The ackApta and ldh double-mutant strain formed significantly less lactate and acetate, and produced a concomitant increase in the excretion of pyruvate (17.8 mM) under anaerobic conditions. The ackA-pta mutant strain accumulated significant acetate but had an approximately 2-fold increase in the formation of lactate. The ackA-pta and ldh double-mutant strain had superior overall performance in large-scale culture under suboptimal conditions, giving 67% higher cell density and 66% higher ThMA activity compared with those of the control strain. The doublemutant strain also achieved a 179% improvement in volumetric ThMA production.

• 열처리공학회지
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• 제17권4호
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• pp.223-229
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• 2004

The effects of the cooling and annealing conditions on the microstructures and corrosion properties were investigated for the Cu-contained Zr-Nb alloy (Zr-1.1Nb-0.07Cu). After annealing at $1050^{\circ}C$ for 15 min, the specimens were cooled by three methods of water quenching, air cooling, and furnace cooling. Widmanstatten structures were developed in both air- and furnace-cooled specimens, and the Widmanstatten plate width of the furnace-cooled specimens was wider than that of the air-cooled ones. The weight gain in the furnace-cooling case was higher than that in the air-cooling case. This could be the reason why the diffusion time was more enough during the furnace cooling than the air cooling. The oxide of the furnace-cooled specimen was nonunformly formed just beneath the Widmanstatten plate boundaries, where ${\beta}_{Zr}$ phases were exised concentrately. Compared with the $640^{\circ}C$ annealing after the water quenching, the $570^{\circ}C$ annealing could make the ${\beta}_{Nb}$ phases and a concomitant reduction of the Nb in the matrix, and then it could improve the corrosion resistance with the increase of the annealing time. It would be concluded that the corrosion resistance of the Zr-1.1Nb-0.07Cu was good when the Nb concentration in the matrix was reached at an equilibrium level and then the ${\beta}_{Nb}$ phase was formed.

• 문화기술의 융합
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• 제7권2호
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• pp.49-60
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• 2021

본 연구는 덕성여자대학교 비교과프로그램 품질관리를 위한 인증평가제의 도입을 검토하는 데에 목적을 두어 실시되었다. 연구 방법은 문헌 분석과 전문가 회의와 같이 두 가지의 절차를 병행하여 구성되었다. 연구 내용은 덕성여자대학교에서 학생들의 학습역량 강화 지원을 위하여 다양하게 운영되고 있는 비교과프로그램의 품질관리를 보다 공식화된 수준과 체계화된 흐름에 따라 시행하기 위한 인증평가제의 도입 관련 수반조건이 구성되었다. 연구 결과, 「비교과인증평가에관한내규」는 비교과프로그램의 상시 모니터링과 연차 성과평가 간 연계적 흐름을 실제화하는 데 주요한 시행 기반이 될 뿐 아니라, 덕성여자대학교를 비롯한 비교과통합관리 지원체계를 구축하고 있는 각 대학별로 공통 사항에 해당된다는 측면을 분석할 수 있었다.

• 대한한방내과학회지
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• 제21권5호
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• pp.747-763
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• 2000

through a literal study upon Arrhythmia between east and west medicine, the results were as follows 1. Arrhythmia is not only irregular cardiac beat but disorder of cardiac impulse making and conduction disturbance. it means almost irregularity of interval between two beat 2. In the east medicine, arrhythmia is represented various category as palpitation, continuous palpitation, dizziness, consumption which give the first consideration by the accompanied symptoms. A separate way in a diagnostics it become a base of diagnosis of diseases and decision of prognosis by the examination of pulse 3. In the west medicine, Arrhythmia is classified as disorder of heart rate, rhythm, conduction disturbance or tachycardia, bradycardia and it is concomitant with fatigue, palpitation, dyspnoea, syncope, chest discomfort 4. The diagnostic study of pulse condition which represent arrhythmia was started from $\mathbb{<}$Nae-Kyung$\mathbb{>}$ and it was revealed as pulse condition of rapid pulse, slow pulse, swift pulse, running pulse, knotted pulse, intermittent pulse etc. Out of them running pulse, knotted pulse, intermittent pulse which obviously are concomitant with irregularity of interval are clinically meaningful in a conditions of disease and decision of prognosis. and the significance of these pulse condition are transformed through the changes of the times 5. According to cause of disease it is classified by Arrhythmia(running pulse, knotted pulse, intermittent pulse) due to heat, cold, phlegm, deficiency(or insufficiency) and There are three categories of etiological factor that is, endogenous, exogenous and non-exo-endogenous factor. the endogenous factor is insufficiency of the heart Ki, deficiency of both Ki and blood, intemal stagnation of phlegm and fluid, stagnation of seven emotions. the exogenous factor is caused by stagnation of Ki and blood by six exogenous pathogenic factor and the non-exo-endgenous factors are improper diet, overstrain, traumatic injury. A cause of arrhythmia in western medicine are a organic and pathological change of the heart itself and malfunction of the autonomic nervous system.