PURPOSES : This study uses deep learning image classification models and vehicle-mounted cameras to detect types of pavement distress — such as potholes, spalling, punch-outs, and patching damage — which require urgent maintenance. METHODS : For the automatic detection of pavement distress, the optimal mount location on a vehicle for a regular action camera was first determined. Using the orthogonal projection of obliquely captured surface images, morphological operations, and multi-blob image processing, candidate distressed pavement images were extracted from road surface images of a 16,036 km in-lane distance. Next, the distressed pavement images classified by experts were trained and tested for evaluation by three deep learning convolutional neural network (CNN) models: GoogLeNet, AlexNet, and VGGNet. The CNN models were image classification tools used to identify and extract the combined features of the target images via deep layers. Here, a data augmentation technique was applied to produce big distress data for training. Third, the dimensions of the detected distressed pavement patches were computed to estimate the quantity of repair materials needed. RESULTS : It was found that installing cameras 1.8 m above the ground on the exterior rear of the vehicle could provide clear pavement surface images with a resolution of 1 cm per pixel. The sensitivity analysis results of the trained GoogLeNet, AlexNet, and VGGNet models were 93 %, 86 %, and 72 %, respectively, compared to 62.7 % for the dimensional computation. Following readjustment of the image categories in the GoogLeNet model, distress detection sensitivity increased to 94.6 %. CONCLUSIONS : These findings support urgent maintenance by sending the detected distressed pavement images with the dimensions of the distressed patches and GPS coordinates to local maintenance offices in real-time.

Mesenchymal stem cells in the dental pulp exhibit a tendency for differentiation into various dental lineages and hold great potential as a major conduit for regenerative treatment in dentistry. Although they can be readily isolated from teeth, the exact characteristics of these stem cells have not been fully understood so far. When compared to twodimensional (2D) cultures, three-dimensional (3D) cultures have the advantage of enriching the stem cell population. Hence, 3D-organoid culture and 3D-sphere culture were applied to dental pulp cells in the current study. Although the establishment of the organoid culture proved unsuccessful, the 3D-sphere culture readily initiated the stable generation of cell aggregates, which continued to grow and could be passaged to the second round. Interestingly, a significant increase in SOX2 expression was detected in the 3D-spheroid culture compared to the 2D culture. These results indicate the enrichment of the stemness-high population in the 3D-sphere culture. Thus, 3D-sphere culture may act as a link between the conventional and 3D-organoid cultures and aid in understanding the characteristics of dental pulp stem cells.

목적 : 본 연구는 65세 미만 성인과 65세 이상 노인에서 삶의 질과 시각기능(VFQ-25)을 파악하기 위한 연구이다. 방법 : 복지관 방문자 79명을 대상으로 한국판 삶의 질 설문지와 시각기능 설문(NEI-VFQ-25)을 사용하여 연 령에 따른 시각기능과 삶의 질에 대한 독립표본 T-검증과 상관분석을 실시하였다. 결과 : 성인의 전체 삶의 질 점수는 3.33±0.65점이며, 노인의 전체 삶의 질 점수가3.59±0.73점으로 높게 나 타났다. 성인의 전체 시각기능의 점수는 67.56±14.46점이며, 노인의 전체 시각기능의 점수는 72.63±15.48로 노인이 성인보다 높게 나타났다. 연령과 삶의 질 간의 사회적 요인에서 유의한 차이를 보였으며 연령과 시각기능 에서는 시력과 관련된 역할의 제한에서만 유의한 차이가 나타났다. 두 요인에서 모두 노인이 성인보다 높게 나타 났다. 성인의 시각적 기능과 개인의 삶의 질의 관계는 높은 것으로 나타난 반면 노인의 시각적 기능과 개인의 삶 의 질은 관계성은 낮은 것으로 나타났다. 결론 : 시각기능과 삶의 질은 연령과 긍정적인 관계가 있는 것을 확인하였다. 이는 개인의 긍정적 삶의 질을 함 양하기 위해서는 단순 개인의 특성만을 강조하는 것보다는 문화 환경적 요소와 주기적인 시각기능 검사가 고려되 어야 할 필요성이 있다.

We investigated the cytotoxic potential of three different commercially available absorbent feminine hygiene products and one transdermal patch using direct contact and extract exposure methods. Two different cell lines were used – mouse fibroblast L929 and normal human skin fibroblast CCD-986sk cell lines. The test samples were extracted using three different methods in accordance to International Organization for Standardization (ISO). Viability of cells was analyzed using MTT assay and morphology of the cells were also observed using phase contrast microscopy. Overall, the direct contact method using L929 cells showed that all the test samples had no toxic effect when exposed to extracts for 1 h. For the exposure method, no toxic effect was observed in both L929 and CCD986sk cells incubated with all the test samples regardless of the extraction methods used.

The study investigates whether differences in metalinguistic information contained in written corrective feedback (CF) mediate its effectiveness for second language (L2) development. To address this, metalinguistic CF was distinguished into three types in terms of how specific its metalinguistic information was. They were then compared among themselves and with non-metalinguistic direct CF in their efficacy for short- and long-term development of explicit and implicit L2 knowledge. The target features for written CF were the English articles, and explicit and implicit knowledge were measured by the error correction test and dictogloss writings by 93 EFL learners respectively. The results suggest that, for both explicit and implicit L2 knowledge, metalinguistic CF was beneficial for short-term development only when it had high levels of specific information while it was effective for long-term development regardless of its type. The findings are discussed from the perspective of SLA theory, and their pedagogical implications and suggestions for future research are put forth.

본 연구는 원통형 종이포트를 활용한 토마토 육묘시, 염스트레스를 활용하여 고온기 도장 억제가능성을 검토하기 위하여 수행되었다. 시험구는 K2SO4, KCl과 KH2PO4을 각 5, 10 dS·m-1로 처리하였고, 또한, 토마토 모종에 고염도의 칼륨을 처리하여 수분 및 저온스트레스 환경에서의 적응성 및 생존성을 조사하였다. 조사결과, 처리 농도가 높아질수록 지상·지하부 건물중, 옆면적, 순동화율 (NAR)이 감소하고, 경경과 충실도는 증가하였다. 수분 스트레스 처리 이후, 대조구는 심한 위조현상을 보였지만, KCl처리구는 양호하였다. 상대수분함량은 대조구에서 23%, KCl처리구에서 8% 감소 하였다. 또한, 대조구에 비하여 KCl 처리구는 저장시(9, 12 및 15°C) 모종의 손상 비율이 낮았다. 이와 같은 결과로 보아, KCl과 같은 고농도의 칼륨 처리가 원통형 종이포트 토마토 육묘의 도장 억제에 효과적이며 환경 스트레스 내성을 향상시키는 것으로 판단된다.