• 한국수산과학회지
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• 제54권2호
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• pp.218-223
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• 2021

In this study, the possibility of use as a cartridge for 3D printing was confirmed by adding calcium to the alginic acid-added surimi mixture. The Alaska pollack Gadus chalcogrammus surimi added with alginic acid was immersed in a calcium solution (1 M calcium carbonate, 1 M calcium chloride, 1 M calcium sulfate, and 0.1 M calcium lactate) to evaluate the physical properties, color differences, and sensory properties of Alaska pollack surimi according to calcium types. As the results, in the case of surimi paste to which 1 M calcium carbonate was added, physical properties were weaker than that of 1 M calcium chloride, but gelation was appropriate and sensory properties was excellent. Addition of 1 M calcium chloride has the best physical properties, but it has a problem of bitter taste. With the addition of 1 M calcium sulfate, it has low solubility and poor physical properties as well as poor elasticity and bad taste. Addition of 0.1 M calcium lactate has weak physical properties but good sensory properties. From these results, 1 M calcium chloride has the best physical properties, but there is a decisive problem in sensory properties, so 1 M calcium carbonate is most suitable for commercial use.

• 상하수도학회지
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• 제36권2호
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• pp.81-95
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• 2022

The present study was performed to investigate the effects of NH₃-N and nitrifying microorganisms on the increased BOD of downstream of the Yeongsan river in Gwangju. Water samples were collected periodically from the 13 sampling sites of rivers from April to October 2021 to monitor water qualities. In addition, the trends of nitrogenous biochemical oxygen demand (NBOD) and microbial clusters were analyzed by adding different NH₃-N concentrations to the water samples. The monitoring results showed that NH₃-N concentration in the Yeongsan river was 22 times increased after the inflow of discharged water from the Gwangju 1st public sewage treatment plant (G-1-PSTP). Increased NH₃-N elevated NBOD levels through the nitrification process in the river, consequently, it would attribute to the increase of BOD in the Yeongsan river. Meanwhile, there was no proportional relation between NBOD and NH₃-N concentrations. However, there was a significant difference in NBOD occurrence by sampling sites. Specifically, when 5 mg/L NH₃-N was added, NBOD of the river sample showed 2-4 times higher values after the inflow of discharged water from G-1-PSTP. Therefore, it could be thought other factors such as microorganisms influence the elevated NBOD levels. Through next-generation sequencing analysis, nitrifying microorganisms such as Nitrosomonas, Nitroga, and Nitrospira (Genus) were detected in rivers samples, especially, the proportion of them was the highest in river samples after the inflow of discharged water from G-1-PSTP. These results indicated the effects of nitrifying microorganisms and NH₃-N concentrations as important limiting factors on the increased NBOD levels in the rivers. Taken together, comprehensive strategies are needed not only to reduce the NH₃-N concentration of discharged water but also to control discharged nitrifying microorganisms to effectively reduce the NBOD levels in the downstream of the Yeongsan river where discharged water from G-1-PSTP flows.

• 한국가금학회지
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• 제49권2호
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• pp.109-114
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• 2022

메추리 근육세포주인 QM7 세포는 다양한 연구에서 이용되고 있다. 세포배양에 있어서, 배양액의 조건은 세포의 성장과 분열에 많은 영향을 미친다고 알려져 있다. 본 연구는 QM7 근육세포 배양에 좀더 적절한 배양액 조성을 맞추어 나가기 위해 진행되었다. 이를 위해 세포배양 시, 기존에 사용하던 배양액에서 10% tryptose phosphate broth(TPB) 대신 2% chicken serum(CS)를 넣어 만든 배양액을 기존 배양액을 사용하는 경우와 비교하였다. CS를 넣어 만든 배양액에서 QM7 근육세포는 가늘고 뾰족한 모양에서 좀더 넓어지는 모양으로 바뀌었다. 또한, 기존 배양액에서보다 CS를 넣어 만든 배양액에서 더 빠르게 성장하고 분열하였다. 이는 세포 계대 후 2일차부터 증가하기 시작하여 3일차부터는 세포수가 유의적으로 많았다. CS를 넣은 배양액에서 유지한 근육세포는 분화 전에는 그 미분화 상태를 잘 유지하고 있다가, 분화를 유도하면 근관 형성이 잘 일어나 길이가 좀더 길고 일정하게 분화되는 것을 확인하였다. 이상의 결과에 따라, QM7 근육세포를 배양하는데 있어서 TPB를 이용하는 것보다 CS를 이용하면, 세포의 유지 및 분화에 있어 더 좋은 결과를 얻을 수 있을 것으로 사료된다.

• 의료법학
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• 제22권2호
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• pp.3-48
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• 2021

2020년에 선고된 주요 판결들 중에는, 독감 및 코로나 백신 접종 부작용으로 시의성이 있는 아나필락시스와 관련하여 의료진의 과실을 인정한 사례와 부정한 사례가 있었고, 기존에도 판례를 통해 인정된 적은 있지만 드문 사례로서 수인한도를 넘어설 만큼 불성실하게 진료를 한 경우 그러한 과실을 별도의 불법행위로 인정하여 위자료 지급을 인정한 판결이 선고되었다. 또한, 손해배상 범위 산정과 관련하여, 맥브라이드를 기준으로 노동능력상실률을 산정해온 관행을 깨고 항소심에서 대한의학회 장애평가기준에 따라 장해율을 산정한 판결이 있었으며, 전화 진료를 비롯한 원격의료는 의료법상 허용되지 않는다는 대법원의 입장을 명확히 하였다는 점에서 의미 있는 판결이 있었다. 설명의무에 관하여는 확립된 법리 위에 개별 사건에서 설명의무 이행 여부를 판단하는 구체적 기준에 관한 세부적인 내용이 더해지는 과정으로 보이며, 진료기록 기재와 관련하여서는 사후기재의 의심이 강하게 들더라도 증명방해에 해당하지 않는다고 판단하였다. 그 외에도, 사실관계가 동일함에도 심급에 따라 과실 및 인과관계 판단이 달라진 판결들에서 원심판결과 대상판결의 차이점을 비교하였으며, 최근 의사의 업무상과실치사상에 대하여 실형이 선고되는 사례가 늘고 있는 상황에서 1심에서 실형을 선고하면서 구체적으로 그 이유에 관하여 설명한 판결을 다루었다.

• 문화기술의 융합
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• 제8권2호
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• pp.399-408
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• 2022

녹용 기능성 소재 개발 연구의 일환으로 녹용 추출물의 유산균 발효를 수행하였다. 총 폴리페놀과 플라보노이드 함량이 증가하고 항산화 활성이 강화된 기능성 소재를 개발하고자 하였다. 유산균 발효중 증식수, 총 폴리페놀 및 총 플라보노이드 함량, DPPH 라디칼 소거 및 항산화 활성을 평가하였다. 녹용 추출물 기질에 이들 4종의 유산균을 첨가한 결과, 측정된 유산균 수는 2.04~5.00×10⁷이었다. 한편, 녹용 추출물에 프로테아제(Baciullus amyloliquefaciens culture: Ma×azyme NNP DS)를 첨가하여 함유된 단백질의 펩타이드 결합을 분해하였다. 그런 다음 이들 4종의 유산균을 첨가하여 배양한 결과 유산균의 수는 2.84107~2.21108로 증가하였다. 총 폴리페놀 함량은 유산균 발효추출물에서 4.82~6.26g/mL이었으며, 프로테아제 효소와 젖산발효 반응 후 14.27~20.58g/mL로 증가하였다. 총 플라보노이드 함량은 유산균 발효추출물에서 1.52~2.21 g/ml이었고, 프로테아제 반응 및 발효 후에는 5.59 ~ 8.11 mg/mL로 증가하였다. 유산균 발효 추출물의 DPPH 라디칼 소거능은 17.03~22.75%였으나, protease 반응과 발효 후에는 32.82~42.90%로 현저히 증가하였다.

• Geomechanics and Engineering
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• 제25권3호
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• pp.207-219
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• 2021

Several additives are used to enhance the geotechnical properties (e.g., shear wave velocity, shear modulus) of soils to provide sustainable, economical and eco-friendly solutions in geotechnical and geo-environmental engineering. In this study, piezoelectric ring actuators are used to measure the shear wave velocity of unreinforced, fiber, cemented, and fiber reinforced cemented Toyoura sand. One dimensional oedometer tests are performed on medium dense specimens of Toyoura sand-cement-fiber-silica flour mixtures with different percentages of silica flour (0-42%), fiber and cement (e.g., 0-3%) additives. The experimental results indicate that behavior of the mixtures is significantly affected by the concentration of silica flour, fiber and cement additives. Results show that with the addition of 1-3% of PVA fibers, the shear wave velocity increases by only 1-3%. However, the addition of 1-4% of cement increases the shear wave velocity by 8-35%. 10.5-21% increase of silica flour reduces the shear wave velocity by 2-5% but adding 28-42% silica flour significantly reduces the shear wave velocity by 12-31%. In addition, the combined effect of cement and fibers was also found and with only 2% cement and 1% fiber, the shear wave velocity increase was found to be approximately 24% and with only 3% cement and 3% fibers this increased to 35%. The results from this study for the normalized shear modulus and normalized mean effective stress agree well with previous findings on pure Toyoura sand, Toyoura silty sand, fiber reinforced, fiber reinforced cemented Toyoura sand. Any variations are likely due to the difference in stress history (i.e., isotropic versus anisotropic consolidation) and the measurement method. In addition, these small discrepancies could be attributed to several other factors. The potential factors include the difference in specimen sizes, test devices, methods of analysis for the measurement of arrival time, the use of an appropriate Ko to convert the vertical stresses into mean effective stress, and sample preparation techniques. Lastly, it was investigated that there is a robust inverse relationship between α factor and 𝞫₀ exponent. It was found that less compressible soils exhibit higher 𝜶 factors and lower 𝞫₀ exponents.

• 한국포장학회지
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• 제28권3호
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• pp.165-170
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• 2022

최근 지구온난화 심화와 환경재난 등으로 석유유래 플라스틱의 분해에 대한 관심이 높아지고 있다. 플라스틱의 분해를 촉진하는 산화촉진제로 ferric ion(Fe²⁺)을 농도별로 첨가하여 필름을 제조하였다. 대조군으로 LLDPE필름과 산화촉진제를 농도별로 첨가한 필름에 UV를 시간별로 조사하여 인장강도, 신장율과 분자량변화를 조사하였다. 수지에 ferric ion 첨가량이 많아질수록 물성저하가 컸으며, 분자량 변화도 큰 것으로 나타났다. 인장강도는 대조군에 비해 산화촉진제 첨가필름이 조사시간 100시간 후 부터는 현저하게 저하되었으며, 이러한 현상은 신장율에서도 비슷한 것으로 나타났다. 분자량은 산화촉진제 첨가에 따른 결과로 UV 조사 50시간 후 63.6%, 100시간 후에는 73.8% 분자량이 감소한 것으로 나타났다. 이상의 결과에서 플라스틱 필름에 산화촉진제인 ferric ion(Fe²⁺)을 첨가함에 따라서 필름의 강도와 분자량이 저하되는 결과와 김 등 등의 보고를 바탕으로 필름의 분자량이 저하되면 그만큼 필름이 분해되고 있다고 판단할 수 있을 것으로 사료되었다.

• Journal of Korean Neurosurgical Society
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• 제65권5호
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• pp.719-729
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• 2022

Objective : The ossification of the ligamentum flavum (OLF) is one of the major causes of thoracic myelopathy. Surgical decompression with or without instrumented fusion is the mainstay of treatment. However, few studies have reported on the added effect of instrumented fusion. The objective of this study was to compare clinical and radiological outcomes between surgical decompression without instrumented fusion (D-group) and that with instrumented fusion (F-group). Methods : A retrospective review was performed on 28 patients (D-group, n=17; F-group, n=11) with thoracic myelopathy due to OLF. The clinical parameters compared included scores of the Japanese Orthopedic Association (JOA), the Visual analogue scale of the back and leg (VAS-B and VAS-L), and the Korean version of the Oswestry disability index (K-ODI). Radiological parameters included the sagittal vertical axis (SVA), the pelvic tilt (PT), the sacral slope (SS), the thoracic kyphosis angle (TKA), the segmental kyphosis angle (SKA) at the operated level, and the lumbar lordosis angle (LLA; a negative value implying lordosis). These parameters were measured preoperatively, 1 year postoperatively, and 2 years postoperatively, and were compared with a linear mixed model. Results : After surgery, all clinical parameters were significantly improved in both groups, while VAS-L was more improved in the F-group than in the D-group (-3.4±2.5 vs. -1.3±2.2, p=0.008). Radiological outcomes were significantly different in terms of changes in TKA, SKA, and LLA. Changes in TKA, SKA, and LLA were 2.3°±4.7°, -0.1°±1.4°, and -1.3°±5.6° in the F-group, which were significantly lower than 6.8°±6.1°, 3.0°±2.8°, and 2.2°±5.3° in the D-group, respectively (p=0.013, p<0.0001, and p=0.037). Symptomatic recurrence of OLF occurred in one patient of the D-group at postoperative 24 months. Conclusion : Clinical improvement was achieved after decompression surgery for OLF regardless of whether instrumented fusion was added. However, adding instrumented fusion resulted in better outcomes in terms of lessening the progression of local and regional kyphosis and improving leg pain. Decompression with instrumented fusion may be a better surgical option for thoracic OLF.

• 유기물자원화
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• 제29권4호
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• pp.5-13
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• 2021

가축분뇨의 요소에서 유래하는 암모니아는 미세먼지(PM2.5) 생성의 주요 전구체로 작용하여 대기질을 저하시키고 공중 보건에 유해한 영향을 미치는 것으로 알려져 있다. 본 연구의 목적은 Acetohydroxamic acid(AHA)의 주입에 따른 요소로부터 암모니아 전환의 억제에 대한 효과를 평가하는 것이었다. 실험은 다양한 요소 농도(500-4,000 mg Urea-N/L), AHA 농도(0-4,000 mg AHA/L), pH(pH 6-10) 및 온도(10-35℃)범위에서 수행되었다. 그 결과 AHA 농도가 높을수록 Urease 억제 효율이 증가함을 보여주었다. 그러나 특정 Urease 억제 활성은 pH가 높을수록 감소하여 pH 6에서 867.1±6.7 Unit/g AHA, pH 10에서 1,167.9±17.4 Unit/g AHA를 나타냈다. AHA와 대조군 모두에서 높은 온도에서 요소분해효소 억제 효율이 감소됨을 확인하였다. 본 연구결과를 통해 AHA가 가축분뇨 관리에서 암모니아 배출을 줄이기 위한 요소분해효소 억제제로 사용될 수 있음을 확인하였다.

• 한국발생생물학회:학술대회논문집
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• 한국발생생물학회 2003년도 제3회 국제심포지움 및 학술대회
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• pp.124-124
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• 2003

The successful development of embryos cloned by nuclear transfer (NT)have been dependent on a wide range of known factors including cell cycle of donor and recipient ooplast, oocyte quality, NT procedure and oocyte activation. The present study compared the development of cloned porcine embryos following different activation treatments. Cumulus-oocyte complexes (COCs) were aspirated from 26 mm follicles of slaughterhouse ovaries and cultured for 22 h in NCSU #23 medium supplemented with 10% porcine follicular fluid, 0.57 mM cysteine, 0.5 g/mL LH, 0.5 g/mL FSH and 10 ng/mL EGF. The COCs were further cultured for an additional 22 h in the same medium at $39{\cird}C$ in an atmosphere of 5% $CO_2$ in air, without hormonal supplements. Primary cultures of fibroblasts isolated from a female fetus on day 40 of gestation were established in DMEM + 15% FCS. For nuclear donation, cells at the 5th-6th passage were cultured in DMEM +0.5% FCS for 5 days in order to arrest the cells in G0/Gl. After enucleation, oocytes were reconstructed by transfer of donor cells and fusion with three DC pulses (1.4 KV/cm, 30 sec) in 0.28 M mannitol containing 0.01 mM $CaCl_2$ and 0.01 mM $MgCl_2$. Eggs were then divided into three treatment groups, control (without further treatment, Group 1), eggs cultured in 10 g/ml cycloheximide (CHX) for 5 h (Group 2), and eggs cultured in 1.9 mM 6-dimethylaminopurine (6-DMAP) for 5 h (Group 3). The eggs were then cultured in sets of 30 in 60 I drops of NCSU#23 supplemented with 4mg/ml BSA (essentially fatty acid free) until day 7 at $39{\circ}C$ in a humidified atmosphere of 5% $CO_2$. On day 4 the culture were fed by adding 20 I NCSU #23 supplemented with 10% FBS. Development rates into blastocysts were significantly higher (P<0.05) in Group 3 embryos compared to Group 1 controls ($27.6 \mu 2.7% vs. 20.1 \mu 4.1%$, respectively), but rates did not differ in Group 2 compared to control ($23.8 \mu 5.7%$). Total cell number in Group 3 blastocysts was however significantly higher (P<0.05) than in Groups 1 and 2 ($44.6 \mu 2.4 vs. 19.9 \mu 1.9 and 21.9 \mu 2.1$, respectively). These results suggest that 6-DMAP is more efficient than cycloheximide in the activation of electrically fused NT oocytes during in vitro production of cloned porcine embryos.