구조물 환기성능 평가에서 기존 사용된 환기 지표 (ACH: Air Change per Hour)는 유체가 거동하는 구조물 내 유량의 흡·배기량과 전체 볼륨에 의해 결정된다. 이는 구조물 내 유체 유동 중 국부적으로 정체된 흐름을 평가하는 지표로 사용하기 부적합하다. 본 논문에서는 구조물에서 국부적으로 정체된 흐름을 정량적으로 나타내기 위해 역류량을 이용하여 새로운 지표 (κ: 역류량 지수)를 제안 하고, 구조형상 변수에 의해 국부적으로 정체된 유체 흐름을 평가한다. 유체 흐름 영향인자로 구조형상 변수는 공극비 (ρ), 공극 개수 (N)로 선정한다. 전산 유체 역학 (CFD)에 의한 해석 결과, 구조형상 변수에 의한 자연 환기 성능은 유사하지만, 공극의 유무에 의한 국부 정체 기류의 크기에는 차이가 발생함이 나타난다. 또한, 역류량 지수는 구조형상 변수 각각 감소함에 따라 값이 증가하는 경향이 나타난다. 본 결과를 바탕으로 회귀분석을 통해 공극비과 공극 개수 변수에 의한 역류량과 역류량 지수의 근사값이 제시된다.

In this study, we investigated the effects of cooling rate during storage on spring kimchi cabbage from an economic perspective. For long-term storage, kimchi cabbage (KC) should be maintained at a low temperature immediately after harvest; however, a sudden change in temperature during storage may lead to chilling injury in KC. The optimal cooling rate is important for the long-term storage of KC. To identify the optimal cooling rate, KC was cooled at different cooling rates (1oC, 2oC, 4oC, 6oC, 8oC, and 24 oC/day), and then stored at 1oC for 90 days. Thereafter, weight, trimming, total loss, pH, free sugar content, and total bacterial count changes were measured. Spring KC stored at the cooling rate of 6 oC/day presented a lower total loss and better sensory properties than KC stored at other cooling rates; thus, 6 oC/day is an appropriate cooling rate for long-term storage of KC.

통영 LNG 기지에서 방류되는 냉배수가 진해만에 미치는 영향을 알아보고, 냉배수의 활용 방안 모색을 위해 총 4개의 냉배수 방류량에 대한 진해만의 환경변화를 1년간(2018년) 모의하였다. 실제 냉배수 방류량인 Case1(10 m3 sec-1)의 모의 결과, 모든 분기에서 냉배 수에 의한 진해만의 환경변화는 매우 미미하게 나타났다. 모의 방류량인 Case2(100 m3 sec-1)의 경우 방류구 반경 5 km 범위에서 1 ~ 3℃의 수온 감소를 보였으며, Case3(1000 m3 sec-1)에서는 방류구 반경 8 km 범위에서 최대 4 ~ 5℃의 수온이 감소하였고 진해만 전 해역에 걸쳐 냉 배수가 확산하는 결과를 보였다. 플랑크톤의 성장 속도는 최대 15% 감소하였으며(11월), 대형조류의 성장 속도는 행암만 부근에서 최대 6 % 증가하는 결과를 보였다. 상기 결과로부터 통영 LNG 기지에서 방류되는 냉배수에 의한 진해만의 환경변화는 미미한 것을 확인하였 다. 또한 Case3 결과로부터 국소지역의 ‘적조 방재’, ‘해조류 성장’을 목적으로 냉배수의 활용이 가능할 것으로 기대된다.

The estimation of the postmortem interval (PMI, the time that has elapsed since the death) is a critical issue for the biosecurity enforcement officers who implement to the timely establishment of biosecurity zone for preventing susceptible animals from disease transmission given the rapid occurrence of an infectious disease. Increasing attention has been paid to PMI of wild boar (Sus scrofa) carcasses associated with African swine fever epidemics in Korea since October 2019 to explain the geographical transmission of the disease, as well as to provide potential target animals for prevention measures in terms of farm biosecurity. This study is, to the best of our knowledge, the first to describe the decomposition process of wild boars in different microhabitats in the country. In the present comparative study, we obtained field data from the decomposition process of the wild boar and domestic pig carcasses continuously exposed aboveground in natural environment settings allowing animal scavenging. This study compared the pattern of decomposition in 16 wild boar carrion and 10 domestic pig carcasses placed between August and November 2019. Quite differences in decomposition rate measured by total body score and tissue's gross morphology over time were observed between wild boars and domestic pigs. Overall, the wild boar decomposed much more slowly than the domestic pig throughout the end of the experimental period. In addition, color changes to the skin were easily seen in domestic pigs, whereas there is much variation in the wild boar, especially carcasses placed in late autumn. Moreover, some wild boar carcasses did not show any sign of bloating. These results indicate that decomposition rates derived from forensic taphonomic studies on domestic pigs may be not directly applicable to the wild boar, hence there is a need to develop regional decomposition models to be employed in different geographical situations to increase the accuracy of PMI of wild boar carcasses.

This experiment was conducted to compare the seed productivity of Spring sown Italian ryegrass(Lolium multiflorum Lam.) depending on the seeding rates(20kg/ha, 30kg/ha, 40kg/ha) in Gangwon region. The experiment was a randomized block design with three replications. The test plots were located in alpine areas of about 600 m above sea level in Gangwon province. The tested Italian ryegrass variety was ‘Greencall’ developed by the National Institute of Animal Science, RDA. Italian Ryegrass was sown on March 26, 2020, and the seed harvesting was on the 60th day(2 July) from heading date. The heading date was May 8 with no difference, There were no significant differences in the agronomic characteristics including plant height. 30kg/ha seed rate was the highest at 146.8 seed/spike and 40kg/ha seed rate was the lowest at 114.7 seed/spike for the number of seeds per spike. The number of spikes per unit area was the highest in 40kg/ha at 886/m2 and the lowest in 20kg/ha at 750/m2. The yield of seed and straw was the highest in 40kg/ha at 1,288kg/ha and 2,970kg/ha respectively, but there was no difference. From the above results, the production of Italian ryegrass seeds through spring sowing in the Gangwon region is not much than autumn seeding, requiring the input of various technologies to increase productivity in the future, and it is desirable to determine the production cost through economic analysis was evaluated.

This study evaluates the radioactivity of concrete waste that occurs due to large amounts of decommissioned nuclear wastes and then determines the surface dose rate when the waste is packaged in a disposal container. The radiation assessment was conducted under the presumption that impurities included in the bio-shielded concrete contain the highest amount of radioactivity among all the concrete wastes. Neutron flux was applied using the simplified model approach in a sample containing the most Co and Eu impurities, and a maximum of 9.8×104 Bq·g−1 60Co and 2.63×105 Bq·g−1 152Eu was determined. Subsequently, the surface dose rate of the container was measured assuming that the bio-shield concrete waste would be packaged in a newly developed disposal container. Results showed that most of the concrete wastes with a depth of 20 cm or higher from the concrete surface was found to have less than 1.8 mSv·hr−1 in the surface dose of the new-type disposal container. Hence, when bio-shielded concrete wastes, having the highest radioactivity, is disposed in the new disposal container, it satisfies the limit of the surface dose rate (i.e., 2 mSv·hr−1) as per global standards.

본 연구에서는 2020년 6월에서 9월까지 4개월 동안 우리나라 하천 중 금강 백제보에 주로 서식하는 말조개, 펄조개와 대칭이를 채집하여 서식처 특성을 살펴보았고, 이들의 여과율을 실내 실험을 통하여 측정하여 검량선을 산출하였다. 백제보에서 채집된 말조개, 펄조개, 대칭이는 24시간 동안 평균 154.84 μg L-1의 Chl-a를 제거하였으며, 이는 실내 수조 (2 L) 내의 식물플랑크톤 C. vulgaris (초기 Chl-a=168.34 μg L-1)를 약 24시간 만에 제거할 수 있는 것으로 나타났다. 따라서, 본 연구에서 사용한 말조개, 펄조개, 대칭이가 연평균 4 만 마리가 서식할 경우 (Lee et al., 2020), 6월 한달 동안 예상되는 Chl-a의 저감 효과는 10.55%으로 예측되고 7월의 경우 34.88%, 8월의 경우 20.14%, 9월의 경우 46.21%로 평균 27.94%의 저감 효과를 예상할 수 있다. 이러한 결과는 간접적으로 이매패류가 서식지에서 효과적으로 Chl-a를 제거 할 수 있을 가능성을 제시한다. 실제로 이매패류를 통하여 수생태계의 조류 제어능력을 평가하기 위해서는 이매패류뿐만 아니라 식물플랑크톤, 수생식물, 저서생물, 퇴적물, 유속 등의 작용들을 종합적으로 고려해야 하지만 본 연구에서는 이매패류의 여과율과 이에 따른 Chl-a에 저감율에 기반하여 수생 태계 조류 제어능력을 산정하였다. 본 연구 결과들은 차후 다양한 요인과 관점에서의 통합된 연구에 기초적인 정보를 제공할 것으로 사료된다.

본 연구는 갈색날개매미충의 기계유유제 처리 방법별 부화율과 산란에 의한 사과 열매의 품질 변화에 대해 조사하였다. 기계유유제 처리 효과를 보면 기계유유제 20배를 도포한 것이 평균 0.57%로 가장 적은 부화율을 보였고, 분무한 가지에서는 평균 1%의 부화율을 보였다. 기계유유제를 50배 도포 처리시 부화율이 약 35%를 보인반면 분무처리는 약 77%를 보여 편차를 고려하면 무처리와 차이가 없는 것으로 보인다. 홍로와 후지 품종에서 갈색날개매미충이 산란한 결과지와 산란되지 않은 결과지에 이듬해 사과 열매가 결실되어도 과실의 품질 차이는 통계적 유의성은 없었다. 또한 갈색날개매미충의 산란에 의한 가지의 부러짐도 없었고, 결과지 생육도 통계적 유의성은 없었다.

Autophagy is a cell survival mechanism that works for the survival of cells under various physiological and pathological conditions. ATG5 is a key protein in the process of autophagy propagation and is involved in tumor development and progression. Chemotherapeutic agents targeting ATG5 enhance the host's immune response in various human cancers and intensify the effectiveness of chemotherapy. However, the physiological role of ATG5 protein in oral squamous cell carcinoma (OSCC) has not been fully recognized. The purpose of this study was to examine the correlation between clinico-pathological factors of OSCC patients and ATG5 immunoexpression through immunohistochemistry (IHC) in the tissues of OSCC patients treated at our hospital, and to analyze the regarding influences and their mechanisms. The authors analyzed 20 OSCC patients from National University Dental Hospital, at Pusan National University from January 2002 to December 2007, which were eligible for the study. Data were obtained by reviewing the medical records of the OSCC patients, and ATG5 immunoexpression was obtained using IHC staining in the tissue samples of the OSCC patients. In the tissue sample of OSCC patients, the immunoexpression of ATG5 elevated, in comparison to the normal oral mucosa, and there was a significant correlation with Drinking, Pathological Stage. In regards to Cox regression analysis, Clinical stage, Tumor size, Histopathologic grade, Cervical nodal metastasis, Loco-regional recurrence, and ATG5 expression have statistically significant correlations. These results imply that the changes in the expression of ATG5 proteins in OSCC can be a prominent factor in the OSCC progression and the prognosis of OSCC patients.

Background/Aim: Endoscopic retrograde cholangiopancreatography (ERCP) training requires varying degrees of staff assistance regarding operation of the fluoroscopy machine via a foot pedal. Efficiency is important to acquire during this training due to radiation risks. In this study, we evaluate the effect of controlling endoscopy and fluoroscopy unit on duct cannulation rates (CRs) and total fluoroscopy time (FT) for fellows in training. Methods: 204 patients undergoing ERCP were randomized to one of two groups: 1) “Endoscopist Driven” group in which the endoscopist controlled the foot pedal for fluoroscopy, and 2) “Assistant Driven” group in which attending or fellow controlled the foot pedal while the other team member controlled the endoscope. Various measures including selective duct CR and total FT were recorded. Results: There was no significant difference in mean procedure duration between the two groups (32 minutes vs. 33 minutes, p=0.70). There was also no statistically significant difference in CR (83.7% vs. 77.4%, p=0.25) or FT (3.27 minutes vs. 3.54 minutes, p=0.48). Conclusions: ERCP is a technically challenging procedure which requires extensive supervision. This study demonstrates that CR and FT are not affected by who controls the fluoroscopy.