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The Growth-Promoting Effect of Pomegranate Concentrates on Lactic Acid Bacteria and Their Application to Yogurt (석류 농축액의 유산균에 대한 성장촉진효과와 요구르트의 적용)

  • Yun Jeong Go;Woan Sub Kim
    • Journal of Dairy Science and Biotechnology
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    • v.41 no.2
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    • pp.76-85
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    • 2023
  • This study investigated the effect of the addition of pomegranate concentrate to yogurt on the growth of pathogenic and lactic acid bacteria. The concentration of the MRS broth was adjusted to one-half and used for an experiment. Pomegranate concentrate was added at concentrations of 4%, 2%, 1%, and 0.5%, which significantly promoted the growth of Lacto-coccus cremoris, Weissella cibaria, Weissella paramesenteroides, Lactobacillus plantarum, Lactobacillus acidophilus, Streptococcus thermophillus, Lactobacillus bulgaricus, and Lactobacillus lactis. The growth of lactic acid bacteria increased with higher concentrations of pomegranate. However, the addition of pomegranate concentrate inhibited the growth of Escherichia coli KCCM11587, E. coli KCCM11591, E. coli KCCM11596, and E. coliKCCM11600. Yogurt with added pomegranate concentrate demonstrated optimal conditions compared to that of the control without the addition. Particularly, the viable cell count of lactic acid bacteria was significantly higher in the yogurt with pomegranate concentrate. Furthermore, the viability of the lactic acid bacteria in the yogurt with pomegranate concentrate was higher than that of the control without the addition of concentrate during storage.

A Study on the Hazard Area of Bunkering for Ammonia Fueled Vessel (암모니아 연료추진 선박의 벙커링 누출 영향에 관한 연구)

  • Ilsup Shin;Jeongmin Cheon;Jihyun Lee
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.29 no.7
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    • pp.964-970
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    • 2023
  • As part of the International Maritime Organization ef orts to reduce greenhouse gas emissions, the maritime industry is exploring low-carbon fuels such as liquefied natural gas and methanol, as well as zero-carbon fuels such as hydrogen and ammonia, evaluating them as environmentally friendly alternatives. Particularly, ammonia has substantial operational experience as cargo on transport ships, and ammonia ship engines are expected to be available in the second half of 2024, making it relatively accessible for commercial use. However, overcoming the toxicity challenges associated with using ammonia as a fuel is imperative. Detection is possible at levels as low as 5 ppm through olfactory senses, and exposure to concentrations exceeding 300 ppm for more than 30 min can result in irreparable harm. Using the KORA program provided by the Chemical Safety Agency, an assessment of the potential risks arising from leaks during ammonia bunkering was conducted. A 1-min leak could lead to a 5 ppm impact within a radius of approximately 7.5 km, affecting key areas in Busan, a major city. Furthermore, the potentially lethal concentration of 300 ppm could have severe consequences in densely populated areas and schools near the bunkering site. Therefore, given the absence of regulations related to ammonia bunkering, the potential for widespread toxicity from even minor leaks highlights the requirement for the development of legislation. Establishing an integrated system involving local governments, fire departments, and environmental agencies is crucial for addressing the potential impacts and ensuring the safety of ammonia bunkering operations.

The experience of stress, coping, and social support of students and parents after the economic crisis: The indigenous psychology approach (IMF시대 이후 초, 중, 고, 대학생과 부모의 스트레스 경험과 대처양식 및 사회적 지원: 토착심리학적 접근)

  • Young-Shin Park;Uichol Kim;Myo-Sung Kim
    • Korean Journal of Culture and Social Issue
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    • v.8 no.2
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    • pp.105-135
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    • 2002
  • The purpose of this study is to examine the experience of stress, coping and social support among students and their parents after Korea recovered from the recent economic crisis. A total of 634 students(primary school=135, junior high school=118, senior high school=168, and university=213) and 842 parents (fathers=421, mothers= 421), for a total of 1,476 participants, completed an open-ended questionnaire developed by the present researchers. For students, the most painful experience was related to problems in academic life, followed by problems in relationship. For father, the most painful experience was financial problems and for mothers, it was conflicts in the family. In stress situations, self-regulation was the most frequently adopted coping style by both students and adults. The second most frequently reported coping style was avoidance. In terms of social support, students reported receiving most support from friends, and the importance of friends became greater for the older students. Parents reported receiving most social support from their spouse. As for the type of social support, around half of students and parents reported receiving emotional support. Emotional support was viewed as being very important in reducing the stress experience related to academic life, problems in relationships, family conflict, and financial difficulties. The results of the present study will be compared to similar studies conducted before and during the economic crisis and the implications of these studies, as well as the importance of the indigenous Korean psychology, will be discussed.

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When do science lessons appeal to students? - Secondary school students' views on the value of school science and the appealing aspects of science lessons to students - (학생들은 어떤 과학수업에 호응하는가?: 학교 과학에 대한 중고등학생들의 가치 인식과 호응 양상)

  • Park, Doo-Chan;Song, Jin-Woong
    • Journal of The Korean Association For Science Education
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    • v.29 no.6
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    • pp.593-610
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    • 2009
  • The purpose of this study was to investigate students' views on the value of school science lessons and the aspects of science lessons that appeal to students. For the investigation, semi-structured in-depth interviews with 16 secondary school students were conducted. The results showed that about half of the participants thought that science lessons are important, but not all students have to learn science. And they considered only intrinsic interest and career hopes as critical elements in judging the necessity of science education for all. To appeal to students: first, science lessons should have relevance to students' career hopes, interest, curiosity, abilities, real life, experiences, and test scores. Second, they should acquire students' understanding. Third, they should include more experiments. Finally, they should be related to real life, reflect students' interest and concerns, and link new things with what students already know in terms of contexts and contents. Students thought that science lessons are not suitable for students who don't desire to pursue a science-related career. This suggests that present science curriculum perceived by students doesn't match well with the idea of science education for all. To overcome this problem, students need to be included in the debate about the relevance of science curriculum.

Education of Humanistic Tendency of Kerschensteiner (케어션스타이너 교육사상의 인문적 전통)

  • Kim, Deok-Chill
    • Journal of Fisheries and Marine Sciences Education
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    • v.13 no.1
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    • pp.117-131
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    • 2001
  • The character of the educational tradition of Germany could be divided into two aspects. One is the humanistic liberal tendency and the other is vocational. From the beginning of the Twentieth Century, however, there has been an attempt to unify these two trends by the . Georg Kerschensteiner is the first of importance to make some comprehensive curriculum for this goal. In Kerschensteiner, the genuine education makes the individual assume his work and role in society, and to develop them by cultivating insight, will and power. His view is well expressed in the slogn "The vocational education is the beginning of the humanistic education." His goal is to make men of independence and autonomy through vocational education. The theory of Kerschensteiner's education is called 'general vocational education'. The reason why is that his vocational education concerns not just technical training for industry, but also general liberal arts. In this point, Kerschensteiner's point of view goes back to Wilhelm von Humboldt, neo-humanist afar in the first half of the Ninteenth Century, and to John Dewey, pragmatist in the contemporary age of Kerschensteiner. Kerschensteiner was much influenced by Humboldt's concepts of power and individuality. These concepts came to be embodied as a principle of vocational education in Kerschensteiner. Furthermore, Humboldt's concept of power could be associated with Dewey's theory of reflexive thinking. The power in Humboldt is to create spirit, which is connected with the world outside through language. The reflexive thinking of Dewey is a process that examines and selects some alternative thinking in the consciousness before acting. This process makes one find the method of problem-solving which results in behaviour. That is the experimental spirit or pragmatic behaviourism. These theories are reduced to the concept of 'work' in Kerschensteiner. And Kerschensteiner's theory of education that has both sides, humanistic and vocational, is similar to that of John Dewey. Dewey brings forward the idea that the vocational education is the best way to cultivate intelligence and emotion, as intelligence operates best in the life. The position of Dewey is in accord with that of Kerschensteiner who intends to cover experiences of various fields of society through practice-learning, and to have knowledge got from outside of school, refuting the misled trend of education isolated from real life. However, there is some difference between Kerschensteiner and Humbolt or Dewey. While the Neo-humanism of Humbolt and the pragmatic education of Dewey put emphasis rather on the liberal arts and culture of individuality, Kerschensteiner is concerned more with the work and life of the reality of society as a group. Kerschensteiner's concept of utility is related to education for the whole man and to the work of the individual and the nation as well as the will and power to practice it. The ideal man of utility of Kerschensteiner is to learn perfectly the value and behaviour of society through vocational life and to have right view of the state establishing a sound mutual relation between individual and state. Kerschensteiner is regarded as a devotee of 'the state of harmony' or 'the ideal of the state', as he makes the state as the criterion for defining the role of the individual. It can be said that Kerschensteiner is not a democrat of the American style as Dewey is, as he makes much of the value of the nation and state. However, he is a humanist and democrat in the point of vocational education. His purpose of education is to make whole men through work and vocational education.

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Microtubule-damaging Chemotherapeutic Agent-mediated Mitotic Arrest and Apoptosis Induction in Tumor Cells (미세소관-손상 항암제 처리에 의한 세포주기의 정지 및 에폽토시스 유도)

  • Jun, Do Youn;Kim, Young Ho
    • Journal of Life Science
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    • v.26 no.3
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    • pp.376-386
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    • 2016
  • Apoptosis induction has been proposed as an efficient mechanism by which malignant tumor cells can be removed following chemotherapy. The intrinsic mitochondria-dependent apoptotic pathway is frequently implicated in chemotherapy-induced tumor cell apoptosis. Since DNA-damaging agent (DDA)-induced apoptosis is mainly regulated by the tumor suppressor protein p53, and since more than half of clinical cancers possess inactive p53 mutants, microtubule-damaging agents (MDAs), of which apoptotic effect is mainly exerted via p53-independent routes, can be promising choice for cancer chemotherapy. Recently, we found that the apoptotic signaling pathway induced by MDAs (nocodazole, 17α-estradiol, or 2-methoxyestradiol) commonly proceeded through mitotic spindle defect-mediated prometaphase arrest, prolonged Cdk1 activation, and subsequent phosphorylation of Bcl-2, Mcl-1, and Bim in human acute leukemia Jurkat T cells. These microtubule damage-mediated alterations could render the cellular context susceptible to the onset of mitochondria-dependent apoptosis by triggering Bak activation, Δψm loss, and resultant caspase cascade activation. In contrast, when the MDA-induced Bak activation was inhibited by overexpression of anti-apoptotic Bcl-2 family proteins (Bcl-2 or Bcl-xL), the cells in prometaphase arrest failed to induce apoptosis, and instead underwent mitotic slippage and endoreduplication cycle, leading to formation of populations with 8N and 16N DNA content. These data indicate that cellular apoptogenic mechanism is critical for preventing polyploid formation following MDA treatment. Since the formation of polyploid cells, which are genetically unstable, may cause acquisition of therapy resistance and disease relapse, there is a growing interest in developing new combination chemotherapies to prevent polyploidization in tumors after MDA treatment.

Enhancement of the Thermostability of a Fibrinolytic Enzyme from Bacillus amyloliquefaciens CH51 (Bacillus amyloliquefaciens CH51이 생산하는 혈전용해효소의 열안정성 개선)

  • Kim, Jieun;Choi, Kyoung-Hwa;Kim, Jeong Hwan;Song, Young-Sun;Cha, Jaeho
    • Journal of Life Science
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    • v.23 no.1
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    • pp.15-23
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    • 2013
  • AprE51 from Bacillus amyloliquefaciens CH51 is a 27 kDa subtilisin-like protease with fibrinolytic activity. AprE51-6 showing increased catalytic activity was produced previously. To enhance the thermostability of AprE51-6, 2 residues, Gly-166 and Asn-218 based on B. subtilis subtilisin E were mutated by site-directed mutagenesis. The results of the mutational analysis showed that substitution of arginine for Gly-166 (AprE51-7) increased the fibrinolytic activity 1.8-fold. An N218S mutant (AprE51-8) also increased the fibrinolytic activity up to 4.5-fold in a fibrin plate assay. Purified AprE51-7 and AprE51-8 mutants had a 1.9- and a 2.5-fold higher $k_{cat}$, respectively, and a 2.1-1.9-fold lower $K_m$, respectively. This resulted in a 3.8- and a 4.7-fold increase in catalytic efficiency ($k_{cat}/K_m$), respectively, relative to that of wild-type AprE51. AprE51-8 had a broader pH range than AprE51-6 and nattokinase, especially at an alkaline pH value. In addition, AprE51-8 showed higher thermostability than AprE51-6 at $60^{\circ}C$. The half-lives of AprE51-7 and AprE51-8 at $50^{\circ}C$ were 21.5 and 27.3 min, respectively, which are 2.0 and 2.6 times longer, respectively, than that of the wild-type AprE51.

Detoxicating Effects of Oriental Herb Extract Mixtures on Nicotine and Dioxin (생약재 추출물의 nicotine 및 dioxin 해독효과)

  • Park, Ki-Moon;Hwang, Jin-Kook;Shin, Kyoung-Min;Kim, Hyun-Suck;Song, Jae-Hwan
    • Korean Journal of Food Science and Technology
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    • v.35 no.5
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    • pp.980-987
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    • 2003
  • In this report, we investigated the detoxication effects of Saururus chinenis, Geranium nepalense, Lonicera japonica, Cassia obtusifolia, Glycyrrhiza uralensis, or their mixtures by employing acute toxicity tests for nicotine and dioxin. When fatal doses $(LD_{100}\;=\;42\;mg/kg)$ of nicotine were injected into the abdominal cavities of ICR mice, those treated with OHEM showed delayed paralysis, half the duration of hyperactivity, and a 73 % survival rate. The results revealed the strong detoxicating effects of the mixtures. We also measured the amount of the degradation product of nicotine and cotinine in humans. Consumption of OHEM promoted (he more specific) the metabolic pathways of nicotine, increasing continine excretion by 1.5 times. As a result the amount of cotinine in urine was reduced to less than 5% after treatment with OHEM. In order to test the toxicity of dioxin, we used TcnN(SD)BR rats exposed to TCDD. While TCDD treatment reduced the blood levels of hemoglobin and platelet, OHEM consumption relieved these effects and, furthermore, helped to recover the number of platelet to the normal level (p<0.05). Moreover, neutrophils (%) and monocytes (%), which were reduced by the injection of TCDD, recovered to normal levels upon treatment with OHEM. The amount albumin reduced by TCDD (p<0.05) normalized, while the activities of GOT and GTP increased by TCDD were reduced. Increases in total cholesterol and neutral fatty acids induced by TCDD were also reduced by OHEM injection (p<0.05). In the kidney, TCDD-induced rises in creatinine were suppressed by OHEM treatment, while decreases in iron levels from TCDD were raised to normal. The treatment of TCDD had more toxic effects in the blood and pancreas than on the liver, kidney and heart. On the other hand, the detoxication of OHEM had significant effects on the liver and pancreas. The normalization by OHEM of various clinical abnormalities induced by TCDD demonstrates the detoxicating effect of OHEM that ameliorates systemic metabolism not properly functioning.

Report for Development of Korean Portable Cardiopulmonary Bypass Machine (한국형 이동식 심폐소생기 개발 보고 I. 실험견을 이용한 개흉식과 폐쇄식 심폐소생술 비교)

  • Kim, Hyoung-Mook;Lee, In-Sung;Baek, Man-Jong;Sun, Kyung;Kim, Kwang-Taik;Kim, Yeon-Soo;Kim, Maeng-Ho;Lee, Hye-Won;Lee, Kyu-Back;Kim, Hark-Jei
    • Journal of Chest Surgery
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    • v.31 no.9
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    • pp.827-836
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    • 1998
  • Background: Effective cardiopulmonary resuscitation (CPR) should provide acceptable hemodynamics for the vital organs during cardiac arrest and early restoration of spontaneous circulation that guarantees long-term, neurologically intact survival. CPR using heart-lung bypass has been suggested as an option for that use. This study was designed to determine the effectiveness of standard CPR techniques, closed-vs. open-chest CPR, which could be used in the future study verifying the role of heart-lung bypass CPR. Material and Method: By using adult mongrel dogs, closed-chest CPR (CCCPR, n=4) and open-chest CPR (OCCPR, n=5) were compared with respects to hemodynamics, restoration of spontaneous circulation(ROSC), and survival. Ventricular fibrillation-cardiac arrest (VF-CA) was induced by electrical shock in all animals. After 4 minutes of cardiac arrest, basic life support (BLS) was applied for 15 minutes and followed by advanced life support (ALS). ALS was maintained until achi ving ROSC but not longer than 30 minutes regardless of the recovery. Resuscitation procedures in either group were standardized by adopting the protocol of American Heart Association. Result: Prearrest baseline hemodynamic data was not different between two groups. During resuscitation, substantially higher systolic pressure was maintained in OCCPR group than in CCCPR group (45$\pm$15 vs. 33$\pm$11 mmHg during BLS, 83$\pm$36 vs. 44$\pm$15 mmHg during ALS; p=NS). Mean pulmonary arterial pressure went up to the level of mean systemic arterial pressures in CCCPR group and to half of that in OCCPR group, and had kept higher in CCCPR group throughout CPR (32$\pm$10 vs. 22$\pm$4 mmHg during BLS and 32$\pm$15 vs. 24$\pm$10 mmHg during ALS; p=NS). ROSC was obtained in 4 of 5 dogs receiving open-chest CPR and 2 of 4 closed-chest CPR. Prolonged survival was noted in all dogs in OCCPR group (6 to 1440 hours) but not in CCPR group (p<.05). Conclusion: These findings indicate that open-chest CPR can be more effective t maintain hemodynamics during cardiac arrest and to obtain restoration of spontaneous circulation and survival. Further experiment will be designed to compare heart-lung bypass CPR with open-chest CPR.

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Performance Characteristics of 3D GSO PET/CT Scanner (Philips GEMINI PET/DT) (3차원 GSO PET/CT 스캐너(Philips GEMINI PET/CT의 특성 평가)

  • Kim, Jin-Su;Lee, Jae-Sung;Lee, Byeong-Il;Lee, Dong-Soo;Chung, June-Key;Lee, Myung-Chul
    • The Korean Journal of Nuclear Medicine
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    • v.38 no.4
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    • pp.318-324
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    • 2004
  • Purpose: Philips GEMINI is a newly introduced whole-body GSO PET/CT scanner. In this study, performance of the scanner including spatial resolution, sensitivity, scatter fraction, noise equivalent count ratio (NECR) was measured utilizing NEMA NU2-2001 standard protocol and compared with performance of LSO, BGO crystal scanner. Methods: GEMINI is composed of the Philips ALLEGRO PET and MX8000 D multi-slice CT scanners. The PET scanner has 28 detector segments which have an array of 29 by 22 GSO crystals ($4{\times}6{\times}20$ mm), covering axial FOV of 18 cm. PET data to measure spatial resolution, sensitivity, scatter fraction, and NECR were acquired in 3D mode according to the NEMA NU2 protocols (coincidence window: 8 ns, energy window: $409[\sim}664$ keV). For the measurement of spatial resolution, images were reconstructed with FBP using ramp filter and an iterative reconstruction algorithm, 3D RAMLA. Data for sensitivity measurement were acquired using NEMA sensitivity phantom filled with F-18 solution and surrounded by $1{\sim}5$ aluminum sleeves after we confirmed that dead time loss did not exceed 1%. To measure NECR and scatter fraction, 1110 MBq of F-18 solution was injected into a NEMA scatter phantom with a length of 70 cm and dynamic scan with 20-min frame duration was acquired for 7 half-lives. Oblique sinograms were collapsed into transaxial slices using single slice rebinning method, and true to background (scatter+random) ratio for each slice and frame was estimated. Scatter fraction was determined by averaging the true to background ratio of last 3 frames in which the dead time loss was below 1%. Results: Transverse and axial resolutions at 1cm radius were (1) 5.3 and 6.5 mm (FBP), (2) 5.1 and 5.9 mm (3D RAMLA). Transverse radial, transverse tangential, and axial resolution at 10 cm were (1) 5.7, 5.7, and 7.0 mm (FBP), (2) 5.4, 5.4, and 6.4 mm (3D RAMLA). Attenuation free values of sensitivity were 3,620 counts/sec/MBq at the center of transaxial FOV and 4,324 counts/sec/MBq at 10 cm offset from the center. Scatter fraction was 40.6%, and peak true count rate and NECR were 88.9 kcps @ 12.9 kBq/mL and 34.3 kcps @ 8.84 kBq/mL. These characteristics are better than that of ECAT EXACT PET scanner with BGO crystal. Conclusion: The results of this field test demonstrate high resolution, sensitivity and count rate performance of the 3D PET/CT scanner with GSO crystal. The data provided here will be useful for the comparative study with other 3D PET/CT scanners using BGO or LSO crystals.