In order to promote the prevention of microbial and enzymatic spoilage and to retain the freshness, sweet persimmons harvested in Gyeongsangnam-do were treated with grapefruit seed extract(GFSE)-CaCO₃ mixture and stored in the proper packaging conditions. A low concentration of GFSE showed effective growth inhibition of plant pathological bacteria and fungi, Enterobacter pyrinus and Fusarium sp., which were involved in the decay of fruits and vegetables. GFSE was stable to heat treatment; its antimicrobial activity was not changed by heat treatment upto 100℃. However, when the temperature was raised to 120℃, about 90% of total activity was retained within 30 min. GFSE was also highly stable to broad pH changes; its activity was not changed in the range of pH 2.0 to pH 12.0. The physiological function of cell membrane in the spores of Bacillus cereus and the hyphae of Fusarium sp. was destroyed by treating with GFSE. It was observed that treating sweet persimmons with GFSE mixture and storing them in strech-wrapped packages could prolong the freshness of sweet persimmons and reduce quality deterioration.

The purpose of this study was to determine whether the vastus medialis oblique muscle(VMO) had greater electrical activity than the vastus lateralis muscle(VL) when hip adduction and knee extension exercise were performed. Electrical activity of the VMO and VL was measured on 42 healthy subjects (28 men, 14 women) during maximal voluntary isometric contractions of hip adduction and knee extension by an EMG-BIOFEEDBACK. The results showed that the electromyographic activity of the VMO was significantly greater than that of the VL during the hip adduction exercise. Differences noted with knee extension by performing hip adduction exercises. Isometric hip adduction exercises, therefore, may be advisable in the treatment of patients with patellofemoral pain.

본 논문은 철근콘크리트 보-기둥 접합부에서 기계적 정착되어진 보의 SD700 고강도 인장철근에 대한 정착성능을 평가하기 위하여 진행되어진 실험의 일부결과를 나타낸 것이다. 보통모멘트 골조에 적용되는 보-기둥 접합부 배근 설계를 하였으며, 실험체는 기둥에 접합되는 보를 제작하지 않고 보 인장철근에 인장을 주고 보 압축응력은 등가면적에 해당하는 압축판 을 이용하여 단순화하여 시험하였다. 실험결과로부터 기계적 정착된 고강도철근의 정착강도, 접합부 전단강도, 철근의 분담 응력, 파괴모드 등이 분석 비교되어진다.

확대머리 SD600 고강도 인장철근으로 단부 정착된 SFRC 깊은보의 전단성능을 평가하기 위해 전단 실험을 수행하였다. 실험 변수는 주인장 철근의 단부 정착방법(확대머리 철근, 일자형 철근), 단부 정착길이, 전단보강근 유무 등이다. 전단경간비는 1을 가지는 실험체에 대한 전단실험결과, 모든 실험체는 초기 휨 균열이 발생한 후 경사균열이 진행되면서 최종적으로 압축전단파괴되었다. 확대머리 철근으로 기계적 정착된 실험체들이 일자형 철근 정착에 비하여 5.6∼22.4% 더 큰 전단강도를 나타내었다. 확대머리 철근으로 기계적 정착된 실험체들에 대하여 최대하중의 75%까지는 지압응력이 전체 정착응력의 0.9~17.2%에 도달하였으나, 최대하중 시점에서 지압응력이 전체 정착응력의 22.4%~46%에 도달하여 큰 응력 부담률을 나타내었다. 이를 통하여 확대머리 지압응력에 의한 정착응력 증가가 전단강도에 큰 영향을 미침을 알 수 있다. 실험 전단강도가 실용식에 의한 전단강도의 2.68~4.65 배로 평가되어, 실용식이 전단내력을 안전측으로 평가하였다.

In this study, we investigated the in vitro anti-biofilm activities of plant extracts of chives (Allium tuberosum), garlic (Allium sativum), and radish (Raphanus sativus L.) against environment harmful bacteria (gram-positive Staphylococcus aureus and, gram-negative Salmonella typhimurium and Escherichia coli O157:H7). In the paper disc assay, garlic extracts exhibited the highest anti-biofilm activity. The Minimal Inhibitory Concentration (MIC) of all plant extracts was generally higher for gram-negative bacteria than it was for gram-positive bacteria. Gram-negative bacteria were more resistant to plant extracts. The tetrazolium dye (XTT) assay revealed that, each plant extract exhibited a different anti-biofilm activity at the MIC value depending on the pathogen involved. Among the plant extracts tested, garlic extracts (fresh juice and powder) effectively reduced the metabolic activity of the cells of food-poisoning bacteria in biofilms. These anti-biofilm activities were consistent with the results obtained through light microscopic observation. Though the garlic extract reduced biofilm formation for all pathogens tested, to elucidate whether this reduction was due to antimicrobial effects or anti-biofilm effects, we counted the colony forming units of pathogens in the presence of the garlic extract and a control antimicrobial drug. The garlic extract inhibited the E. coli O157:H7 biofilm effectively compared to the control antimicrobial drug ciprofloxacin; however, it did not inhibit S. aureus biofilm significantly compared to ciprofloxacin. In conclusion, garlic extracts could be used as natural food preservatives to prevent the growth of foodborne pathogens and elongater the shelf life of processed foods.

In this paper, the shear performance of the deep beams with high strength headed reinforcement was evaluated. The experimental parameters are high strength headed bar a gunboat. The shear span-depth ratio (a/d) of specimens was 1. The development length of headed reinforcement was evaluated to have a great influence on the shear strength of the deep beam.

In this paper, the shear performance of the deep beams with high strength headed reinforcement was evaluated. The experimental parameters are horizontal stiffener and fusing length. The shear span-depth ratio (a/d) of specimens was 1. The development length of headed reinforcement was evaluated to have a great influence on the shear strength of the deep beam.

The goal of this experimental works is to evaluate the influence of shear strength according to shear span to depth ratio of RC deep beam with high-strength hooked bars. A total of 3 specimens were constructed and tested in three-point bending up to failure. The test variables included the shear span to depth ratio (0.75, 1.0, 1.25). Specimens had a failure mode of shear fracture. For specimen with shorter shear span to depth ratio, it showed that maximum shear strength was higher and that more brittle behavior occurred.

이 연구의 목적은 대학 글쓰기 교육의 성공적 요인으로 중시하는 ‘글쓰기 교과 교수 개발 프로그램’의 내용과 효과를 경험적으로 분석하여, ‘글쓰기 교과 교수 개발 프로그램’의 발전 방안을 모색하는 데 있다. 전남대학교에서 지난 4년 동안(2005-2008) 개발하여 운영한 교수 개발 프로그램의 내용 분석 결과, 글쓰기 교과 교수 개발 프로그램의 유형은 ‘글쓰기 강사 워크숍’, ‘특별 연수 프로그램’, ‘더 나은 가르침을 위한 교수공동체’ 등으로 세분화되어 있었다. ‘글쓰기 강사 워크숍’의 주제는 교재 분석, 강의안 개발, 피드백 사례 공유 등이었다. ‘글쓰기 강사 워크숍’의 효과 분석을 위해 9차 워크숍에 참여한 43명의 강사들을 대상으로 한 설문 분석 결과, 워크숍은 실제 강의에 도움이 되며, 워크숍에 많이 참석한 강사들이 적게 참석한 강사들보다 강의에 어려움을 덜 겪는 것으로 나타났다. 결론에서는 교과 개선을 위한 교수 개발 프로그램 개발 및 운영과 관련하여 유념해야 사항을 ‘프로그램 목적의 명료화’, ‘워크숍 참여의 의무화’ ‘평가의 중요성’ 등 세 가지로 나눠 논의했다.

황금의 천연항균제 개발을 위하여 황금의 일반성분 및 미량물질들을 분석하였으며 항균활성물질의 검색을 위하여 LC-MS를 이용하였고 검색되어진 성분들에 대해서는 항균력 비교시험을 하였으며 항균활성물질들에 대해서는 HPLC를 이용하여 그 양을 정량하였다. 황금의 일반성분으로는 수분 , 탄수화물 , 조회분 , 조단백질 및 조지방 이었고 미량성분에 있어서는 칼륨 12,050mg/kg과 마그네슘4,296 mg/kg의 함량이 현저하게 높았다. LC-MS

To develop natural antimicrobial agents for keeping qualities of postharvested greenhouse produce the antimiocrobial actions of Polygonum cuspidatum Sieb. et Zucc. extract , which showed remarkable antimicrobial effects against microorganism causing the postharvest decay of greenhouse produce, were investigate. In the inhibitory experiment of enzymes related to energy production metabolism hexokinase activities decreased to 73% and 68% by treating with Polygonum cuspidatum Sieb. et.Zucc. extract and Eugenia caryophyllata Thumnberg extract in comparison with control, respectively. Direct visualization of microbial cells by using both transmission electron microscope and scanning electron microscope showed that microbial cell membrane was destroyed by treating with the dilute extract solution. this change of celluloar membrane permeability could be identified in the experiment that 0-nitrophenyl--D-galactopyrano-side(ONPG), the artificial substrate of -galactosidase, was hydrolyzed in the presence of the extract, indicating that the membrane was perturbed. The separation and identification of the most antimicrobialo substances isolated from Polygonum cuspidatum Sieb et. Zucc. extract and Eugenia caryophyllata Thunberg extract were carried out by using gas chromatography and mass spectrometry 9GC/MSD), which were identified as eugenol. As a result, the functionality of Polygonum cuspidatum Sieb. et Zucc. extract and Eugenia caryophyllata Thunberg extract as antimicrobial agents for keeping qualities of postharvested greenhouse produce may be recommended.

약용식물로부터 항균활성소재를 ethanol로 추출하고, 각 추출물의 시설원예산물에 대한 선도유지제로서의 기능과 효능을 입증하기 위하여, 변패된 시설원예산물에서 분리된 Bacillus cereus, Corynebacterium xerosis, Pseudomonas syringae 및 Enterobacter aerogenes를 공시균주로 사용하여 항균성을 실험한 결과, 호장, 정향, 치자, 황금, 적작약, 결명자 등에서 항균성을 확인하였고, 여기에서

To investigate the antimicrobial activities and effect of grapefruit seed extract(GFSE) on the physiological function of microorganism, antimicrobial activity, fatty acids of bacterial cell lipid and amino acids of bacterial cell protein were measured. The change of cell morphotype was observed by transmission electron microscope. GFSE was very stable on the wide range temperture and pH. The growth rate of E. coli and B. suvtilis were decreased above 40ppm GFSE There fore, minimum inhibitory concentration (MIC) of the E. coli and B. subtilis to GFSE were determined around 40ppm. In the change of fatty acids quantities, hexadecanoate was significantly decreased on the treatment compared with control in case of E. coli, whereas tridecanoate was not detected in case of B. subtilis. In the change of amino acids quantities, alanine, glutamic acid, glycine, lysine were decreased on the treatment compared with control in case of E. coli and B. subtilis Transmission electron microsgraphs(TEM) showed the microbial cells were destroyed by GFSE.