• 한국어병학회지
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• 제20권3호
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• pp.257-267
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• 2007

The hypo-salinity effects on fertilized eggs, embryos and larvae were investigated in olive flounder (Paralichthys olivaceus) obtained from hatcheries in Cheju-Island, Yeosu and Chungnam. Those were treated to eight concentration; 0, 3.4, 6.7, 10.1, 13.4, 20.2, 27.4 and 33.6 ‰. It was not discrepancy in the survival rate and hatching success rate of fertilized embryos obtained from different regions. Also, in the larvae, the regional difference was not appeared. The survival rate and hatching ability of embryos significantly diminished in the lower groups than 13.4 ‰ compared to 33.6 ‰. After fertilization, namely embryos are tolerant of a wide range of salinity (13.4 - 33.6 ‰). Reduced salinity induced an increase of the malformed embryo and larvae including various deformities; irregular embryos membrane (or yolk sac depression), fin erosion and swim bladder inflation in the flounder embryo. The hatching success of embryos was significantly reduced in lower salinity than 13.4 ‰. Notably, the reduction of larval survival rate significantly was observed in ≤10.1 ‰ treated groups with the same manner of survival rates of the embryos. Additionally, olive flounder was found to be adequate model for measuring external impulses because there are no the regional differences.

• 한국동물번식학회:학술대회논문집
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• 한국동물번식학회 2001년도 발생공학 국제심포지움 및 학술대회 발표자료집
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• pp.47-47
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• 2001

One of the problems associated with in vitro culture of primordial germ cells (PGCs) is the large loss of cells during the initial period of culture. This study characterized the initial loss and determined the effectiveness of two classes of apoptosis inhibitors, protease inhibitors and antioxidants, on the ability of porcine PGCs to survive in culture. Results from electron microscopic analysis and in situ DNA fragmentation assay indicated that porcine PGCs rapidly undergo apoptosis when placed in culture. Additionally,？ 2-macroglobulin, a protease inhibitor and cytokine carrier, and N-acetylcysteine, an antioxidant, increased the survival of PGCs in vitro. While other protease inhibitors tested did not affect survival of PGCs, all antioxidants tested improved survival of PGCs (p〈0.05). Further results indicated that the beneficial effect of the antioxidants was critical only during the initial period of culture. Finally, it was determined that in short-term culture, in the absence of feeder layers, antioxidants could partially replace the effect(s) of growth factors and reduce apoptosis. Collectively, these results indicate that the addition of ？2-macroglobulin and antioxidants can increase the number of PGCs in vitro by suppressing apoptosis.

• 응용통계연구
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• 제35권1호
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• pp.35-47
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• 2022

Receiver operating characteristic (ROC) 곡선은 이항 반응 자료에 대한 마커의 분류 예측력을 측정하기 위해 널리 적용되어왔으며 최근에는 생존 분석에서도 매우 중요한 역할을 하고 있다. 여러 가지 유형의 중도 절단과 원인 불명 등 다양한 종류의 결측 자료를 포함한 생존 자료 분석에서 마커의 사건 발생 여부에 대한 예측력을 판단하기 위해 기존의 통계량을 확장하였다. 생존 분석 자료는 각 시점에서의 사건 발생 여부로 이해할 수 있으며, 따라서 시점마다 ROC 곡선과 AUC를 구할 수 있다. 본 논문에서는 우중도 절단과 경쟁 위험 모형하에서 사용되는 다양한 방법론과 관련 R 패키지를 소개하고 각 방법의 특성을 설명하고 비교하였으며 이를 검토하기 위해 간단한 모의실험을 시행하였다. 또한, 프랑스에서 수집된 치매 자료의 마커 분석을 시행하였다.

• Membrane and Water Treatment
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• 제14권3호
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• pp.141-146
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• 2023

Algal organic matters (AOMs) are challenging to remove using traditional water treatment methods. Additionally, they are recognized as disinfection by product (DBP) precursors during the chlorination process. These compounds have the potential to seriously harm aquatic creatures. Despite the fact that AOMs and DBPs formed from algae can harm aquatic species by impairing their cognitive function and causing behavioral problems, only a few studies on the effects of AOMs and associated DBPs have been conducted. To assess the impact of extracellular organic materials (EOMs) produced by three different hazardous algal species and the chlorinated EOMs on zebrafish, this study used fish acute embryo toxicity (FET) and cognitive function tests. With rising EOM concentrations, the embryo's survival rate and mental capacity both declined. Of the three algal species, the embryo exposed to Microcystis aeruginosa EOM exhibited the lowest survival rate. On the other hand, the embryo exposed to EOMs following chlorination demonstrated a drop in CT values in both the survival rate and cognitive ability. These findings imply that EOMs and EOMs treated with chlorine may have detrimental effects on aquatic life. Therefore, an effective EOM management is needed in aquatic environment.

• Korean Journal of Radiology
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• 제22권10호
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• pp.1697-1707
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• 2021

The recent introduction of various high-dimensional modeling methods, such as radiomics and deep learning, has created a much greater diversity in modeling approaches for survival prediction (or, more generally, time-to-event prediction). The newness of the recent modeling approaches and unfamiliarity with the model outputs may confuse some researchers and practitioners about the evaluation of the performance of such models. Methodological literacy to critically appraise the performance evaluation of the models and, ideally, the ability to conduct such an evaluation would be needed for those who want to develop models or apply them in practice. This article intends to provide intuitive, conceptual, and practical explanations of the statistical methods for evaluating the performance of survival prediction models with minimal usage of mathematical descriptions. It covers from conventional to deep learning methods, and emphasis has been placed on recent modeling approaches. This review article includes straightforward explanations of C indices (Harrell's C index, etc.), time-dependent receiver operating characteristic curve analysis, calibration plot, other methods for evaluating the calibration performance, and Brier score.

• Journal of Microbiology
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• 제43권spc1호
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• pp.93-100
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• 2005

It had long been assumed that a bacterial cell was dead when it was no longer able to grow on routine culture media. We now know that this assumption is simplistic, and that there are many situations where a cell loses culturability but remains viable and potentially able to regrow. This mini-review defines what the 'viable but nonculturable' (VBNC) state is, and illustrates the methods that can be used to show that a bacterial cell is in this physiological state. The diverse environmental factors which induce this state, and the variety of bacteria which have been shown to enter into the VBNC state, are listed. In recent years, a great amount of research has revealed what occurs in cells as they enter and exist in this state, and these studies are also detailed. The ability of cells to resuscitate from the VBNC state and return to an actively metabolizing and culturable form is described, as well as the ability of these cells to retain virulence. Finally, the question of why cells become nonculturable is addressed. It is hoped that this mini-review will encourage researchers to consider this survival state in their studies as an alternative to the conclusion that a lack of culturability indicates the cells they are examining are dead.

• 한국가금학회지
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• 제44권3호
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• pp.189-198
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• 2017

본 연구는 국산 신품종 토종닭 개발을 위하여 국내 보유중인 원종계 5계통을 대상으로 $5{\times}5$ 이면교잡을 통해 생산된 교배조합종 암컷 1,157수를 대상으로 조합별 능력을 검정하고, 이를 이용하여 결합능력 및 상반교잡효과를 추정하였다. 생산능력에 대한 검정형질로는 체중, 생존율, 시산일령, 난중 및 산란율을 대상으로 하였다. 분석 결과, 일반결합능력에 있어 생존율은 -9.6~11.1의 범위를 보이며 W계통이 가장 높았고, 12주 체중에서는 F계통이 가장 높은 추정치를 보이며, -209.7~162.2의 범위로 추정되었다. 산란형질에 대한 일반결합능력의 추정치는 시산일령에서 -2.8~3.7, 난중은 -0.91~0.96, 일계산란율은 -4.9~6.0의 범위를 보이며, W계통이 가장 높은 산란율을 나타내었다. 특정결합능력의 추정 결과, 생존율은 Y와 W계통 간의 조합이, 12주 체중은 F와 W계통 간의 조합이 가장 높았으며, 일계산란율은 G와 W간의 조합이 가장 높게 추정되었다. 상반교잡효과의 분석 결과, 거의 모든 형질에서 유의한 차이를 보이며, 동일한 교배조합이라 할지라도 어느 쪽을 부모계로 이용하느냐에 따라 상이한 능력의 차이를 보였다. 결합능력을 근거로 한 조합가의 추정치로 생존율은 WY, WF, GW 순으로 높았고, 12주 체중에서는 GF, HG, HF 순으로 높았으며, 일계 산란율은 GW, YW, FW 순으로 높은 추정치를 나타내었다. 이상의 결과를 바탕으로 우수한 실용계(commercial chicken)를 작출하기 위한 최적의 종계(parents stock) 조합의 선정은 부 계통으로는 체중이 우수하면서 상대적으로 생존율이 양호한 GF나 HF조합이 적합할 것으로 사료되고, 모 계통은 산란능력이 우수하며 적절한 체중을 지닌 GW나 FW조합이 가장 바람직 할 것이라 사료된다.

• International Journal of Industrial Entomology and Biomaterials
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• 제24권1호
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• pp.7-16
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• 2012

To meet the local requirement i.e. the tropical stress of Andhra Pradesh and marginal farmers, twenty four new hybrid combinations were tested in Line x Tester method involving eight newly developed polyvoltine oval lines viz., MSO1, MSO2, MSO3, MSO4, MSO5, MSO6, MSO7 and MSO8 and three bivoltine silkworm breeds viz., APS12, APS45 and APS8 as testers. These hybrids were reared to evaluate their performance. Data for eight economically important metric traits viz., fecundity, cocoon yield per 10,000 larvae by number, cocoon yield per 10,000 larvae by weight, survival rate, cocoon weight, cocoon shell weight, cocoon shell ratio and filament length was recorded. General combining ability (gca), specific combining ability (sca) and heterosis were analyzed. Further, the relative merit of the hybrids for all the traits under study was also assessed adopting Evaluation Index method. Based on combining ability effects, heterosis and evaluation index, five hybrid combinations viz., MSO3 $\times$ APS45, MSO1 $\times$ APS12, MSO7 $\times$ APS8, MSO2 $\times$ APS45 and MSO1 $\times$ APS45 were selected for further evaluation in different seasons.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제42권5호
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• pp.243-250
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• 2016

Objectives: Many studies have examined histopathological factors and various prognostic scores related to inflammation to predict outcomes. Here, we examined the prognostic value of the C-reactive protein/albumin (CRP/alb) ratio in oral squamous cell carcinoma (OSCC). Materials and Methods: This retrospective study included 40 patients with OSCC. Using univariate and multivariate analyses, we focused on the correlation of the CRP/alb ratio with clinicopathological characteristics and with overall survival. We then compared five inflammation-based prognostic scores, CRP/alb ratio, modified Glasgow Prognostic Score (mGPS), neutrophil-lymphocyte ratio (NLR), platelet-lymphocyte ratio (PLR), and prognostic nutritional index (PNI), based on receiver operating characteristic (ROC) curves. Results: The optimal cut-off value for the CRP/alb ratio was 0.085. The group with a high CRP/alb ratio had a high TNM clinical stage (P=0.002) and larger primary tumors (P=0.029), with statistically significant differences in lymph node metastasis and distant metastasis. In addition, when the CRP/alb ratio was high, multivariate analysis showed a lower survival rate (P=0.002; hazard ratio=6.078), and the ROC curve showed more outstanding discriminatory ability regarding overall survival compared to other inflammation-based prognostic scores. Conclusion: The CRP/alb ratio can be an independent prognostic factor when predicting prognosis in OSCC and has good prognostic ability.

• 한국양식학회지
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• 제11권4호
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• pp.521-528
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• 1998

자주복 Takifugu rubripes 자어의 섭이상태에 관한 기초 지식을 얻기 위하여 수온 16.5~18.5${\circ}C$ 범위의 급이와 무급이 조건하에서 초기자어의 성장, 생존율 그리고 섭이율 등을 비교, 조사하였다. 자주복 자어는 부화후 5일 전후에서 난황흡수의 내부영양에서 외부영양으로의 전환이 시작되고, 이 시기에 있어 섭이의 유무는 그후 자어의 성장, 생존율에 큰 영향을 미치는 것이 사육실험 결과 밝혀졌다. 무급이 자어는 부화후 16일에 전 개체가 사망하나, 초기사망의 출발점은 유구가 흡수되는 부화후 9일(기아 5일)경부터 추측된다. 급이구와 무급이구 자어의 성장을 비교한 결과, 무급이구에서는 부화후 4일경부터 성장이 정지되고, 부화후 7일이후는 성장 감소를 보였다. 기아상태에 놓여있는 자어의 섭이율 변화는 기아일수 경과에 따른 자어의 유영력과 깊은 관계가 있는 것으로 생각된다. 따라서 자주복 종묘생산시급이 개시시기는 가능한 빨리 결정하는 것이 건강한 종묘의 생산과 높은 생존율을 향상시킬 수 있다.