Object Classification and Segmentation Based on Deep Learning Using Underwater Mapping Data

This paper presents a fast and accurate classification method for underwater objects using underwater mapping data obtained by a small Autonomous Underwater Vehicle (AUV) and autonomous surface vehicle (ASV). For the mapping data, in addition to underwater acoustic reflection intensity images, water depth data, point cloud data and backscattering reflection intensity data are employed. We propose the automatic classification and semantic segmentation method on deep learning using a convolutional neural network (CNN) and PointNet++. In order to verify the effectiveness of the present method, we applied it to the measured several underwater mapping data

歯の機械的刺激による神経興奮を放射断層撮影法を用いて検討した予備研究

Dentists often cannot objectively find abnormalities in patients who complain of discomfort or abnormal sensation in their dental occlusion. We hypothesized that abnormal neural transmission from the tooth is related to this occlusal discomfort sensation. Chronic tooth contact habits may induce neural excitation from the tooth to the central nervous system, and may aggravate the sensation of discomfort in the central nervous system. However, the details of neural transmission from the tooth to the central nervous system are still unclear. In this study, we stimulated a rat premolar mechanically and observed activated bran sites using positron emission tomography (PET) and 18F-2-fluoro-2-deoxy-D-glucose (FDG). We anesthetized 5-7-week-old male rats using isoflurane inhalation anesthesia and stimulated the upper right premolar mechanically with an electric von Frey system (Model 1601C, IITC Instruments) by measuring mechanical pressure. Before the tooth mechanical stimulation, we injected FDG through the rat’s caudal vein and then used a stimulation intensity of 100, 200 or 300 g. We recorded FDG accumulation with PET. The PET brain images were separated into four parts (right higher, left higher, right lower and left lower) for analysis and the peak value of striatal uptake (SUV) in each part was analyzed. The PET images showed that the accumulated FDG in the right lower part of the brain was higher with 300 g tooth stimulation than with 100 or 200 g. The data showed that the tooth stimulation site in the lower part of the brain was activated with tooth stimulation by comparing it with the other parts. We also measured SUV in the right and left sensory areas, motor area, hippocampus, trigeminal ganglia (TG) and spinal cord. The TG and sensory area showed more FDG accumulation compared with mouth opening.咬合違和感を訴えて来院した患者に対して，歯科医師は咬合状態に客観的な異常を見つけることができないこともよくある．我々は歯からの神経伝達が咬合違和感と何らかの関連をしているのではないかと仮説を立てて研究を行っている．慢性的な歯への刺激が歯から中枢における神経興奮に関連しており，中枢での咬合違和感を悪化させるのかもしれないと考えられる．しかしながら，歯から中枢への神経伝達の詳細は不明である．この研究ではラットの小臼歯を機械的に刺激して，脳の活動部位を18F-2-フルオロ-2-デオキシ-D-グルコース （FDG）を用いて放射断層撮影法（PET）により計測した．5〜7 週齢のラットをイソフルレンを用いて全身麻酔し，電気的フォンフレイ刺激装置を用いて刺激圧を計測しながら上顎右側小臼歯を刺激した．歯の刺激前にFDG を尾静脈から注射し，100，200，300g の刺激力を用いて刺激した． 脳PET 画像は脳を4 分割（右上，左上，右下，左下）して，ピーク値を計測したところ，右下部においては300g の刺激力は100，200g よりもFDG の集積が観察された．この結果は歯の刺激により脳の右下部位が活動することを示していると考えられる．また，知覚部位，運動部位，海馬，三叉神経節，脊髄に分類して観察したところ，三叉神経節と知覚部位においてFDG の集積が観察された

Mandibular movement during sleep bruxism associated with current tooth attrition

Patient: Observation of attrition patterns suggests that mandibular movement in sleep bruxism (SB) may be associated with current tooth attrition. The aim of this study was to confirm this phenomenon by investigating mandibular movement and masseter muscle activity. The subject was a healthy 21-year-old Japanese male. We recorded biological signals including mandibular movement and masseter electromyograms (EMGs) with a polysomnograph. Based on the EMG using Okura’s criteria, SB events were classified into clenching, grinding and mixed types according to mandibular movement criteria. The close-open mandibular movement cycles (CO-cycles) during grinding and mixed type events were selected based on mandibular movement trajectories. Discussion: Fifty-eight CO-cycles were selected in seven grinding and three mixed types. We found that SB mandibular movements associated with current tooth attrition. Excessive lateral movements (ELM) beyond the canine edge-to-edge position were observed in the closing (10.3%) and opening (13.8%) phases of the CO-cycle. Total masseter muscle activity was significantly higher during voluntary grinding (VGR) than during CO-cycle including ELM (working side: P = 0.036, balancing side: P = 0.025). However, in the middle and late parts of the opening phase, working side masseter muscle activity was significantly higher during CO-cycle including ELM than during VGR (P = 0.012). In the early part of the closing phase, balancing side masseter muscle activity was significantly higher during CO-cycle including ELM than during VGR (P = 0.017). Conclusion: These findings suggest that excessive forceful grinding during ongoing SB events may have caused canine attrition in this patient

シカ ホテツガク ジュギョウ ニオケル Team-Based Learning ノ ドウニュウ ト ソノ コウカ

Team-Based Learning (TBL) was introduced into our prosthodontic education for thirdyear dental school students. Forty students (26 males and 14 females) of Tokushima University School of Dentistry attended the TBL-style fixed prosthodontic course. A total of fifteen classes (60 minutes each), which started with six conventional lecture-style classes followed by 8 TBL-style classes, were held. The effectiveness of TBL was evaluated with student questionnaires at the end of each class and with the results of the term-end examination. The results of the questionnaire on some questions and term-end examination exhibited higher score for the TBL. The results of this study showed that TBL-style classes were more effective than that of the conventional lecture-style classes for the fixed prosthodontic course

Comparison between flipped classroom and team-based learning

Purpose: We previously investigated the effects of team-based learning (TBL) on fixed prosthodontic education and reported that TBL could have higher efficiency with high student satisfaction than traditional lecture. In the current report, we introduced flipped classroom to the fixed prosthodontic education and compared their effectiveness based on the final examination score in addition to TBL. Methods: Participants were forty-one students from XXXXXX University School of Dentistry who attended a fixed prosthodontics course. The first six classes adopted the flipped classroom style while the latter eight classes adopted TBL. To evaluate the relationship between learning styles and their effectiveness, we compared results from the term-end examination between the curriculum covered by flipped classroom and TBL-style classes. To draw comparisons, a referential examination with the same questions was conducted to eight faculty members who had not attended any of these classes. Results: Term-end examination results showed that TBL classes had slightly higher scores than flipped classroom classes. Referential examination results also showed higher scores for the same curriculum and no significant interaction was found between class formats and the term-end and referential examination scores. Analysis revealed no noticeable difference in the effectiveness of the class formats. Conclusion: Our previous study reported that TBL had higher efficiency than traditional style lecture. In the current study, there was no statistical difference in the examination score between flipped classroom and TBL. Therefore, we conclude that both styles are highly effective than traditional style lecture and constitute valid formats for clinical dental education

Validity of Peer Evaluation for Team-Based Learning in a Dental School in Japan

The aim of this study was to determine the validity of peer evaluation for team-based learning (TBL) classes in dental education in comparison with the term-end examination records and TBL class scores. Examination and TBL class records of 256 third- and fourth-year dental students in six fixed prosthodontics courses from 2013 to 2015 in one dental school in Japan were investigated. Results of the term-end examination during those courses, individual readiness assurance test (IRAT), group readiness assurance test (GRAT), group assignment projects (GAP), and peer evaluation of group members in TBL classes were collected. Significant positive correlations were found between all combinations of peer evaluation, IRAT, and term-end examination. Individual scores also showed a positive correlation with group score (total of GRAT and GAP). From the investigation of the correlations in the six courses, significant positive correlations between peer evaluation and individual score were found in four of the six courses. In this study, peer evaluation seemed to be a valid index for learning performance in TBL classes. To verify the effectiveness of peer evaluation, all students have to realize the significance of scoring the team member’s performance. Clear criteria and detailed instruction for appropriate evaluation are also required

Effects of Team-Based Learning on Fixed Prosthodontic Education in a Japanese School of Dentistry

The aims of this study were to evaluate the quality of team-based learning (TBL) in prosthodontics education for fourth-year dental students at Tokushima University School of Dentistry and to compare this teaching method with traditional lecture-based delivery. Participants in the study were 36 students (22 males and 14 females) who attended the TBL-style fixed prosthodontics course. Ten 60-minute classes were held. The first three were traditional lecture-style classes and were followed by one class introducing the TBL style. The remaining six classes constituted the TBL-format fixed prosthodontics course. The effectiveness of TBL was evaluated through student questionnaires at the end of each class and the results of the term-end examination. The questionnaire revealed high student approval for TBL-style learning, and active group discussion among students during TBL was a key factor in these ratings. In the results of the term-end examination, there were significantly higher scores on the questions that covered TBL-taught material than those covering traditional lecture-taught topics. The results of this study suggest that TBL-style lecture was more effective than traditional-style lecture for teaching fixed prosthodontics and that TBL was a more efficient mode of delivering dental education than traditional lecture-based teaching

Performance of Air Curtain located at the top of entrance opening - Difference among indoor/outdoor/double-sided installation

Large openings of buildings are often used open, which results in heat loss due to intrusion of outdoor airflow and leakage of indoor air through the opening. To reduce air-conditioning load and to improve thermal environment in such a building, installing an air curtain at the opening can be a beneficial technique. The airflow blowing out of the device suppresses the heat exchange by buoyancy-induced convection through the opening. The impact of temperature difference, blowing speed, and installation position of the air curtain on temperature distribution and invasion flow rate of outdoor air was investigated by full-scale experiment under heating operation. Thermocouples were installed to measure vertical temperature distribution. Outdoor air infiltration was measured using tracer-gas method. The amount of outdoor air infiltration was evaluated based on both temperature difference and CO2 concentration. Comparing the results, it was found that the indoor air curtain was able to suppress the airflow through the opening. The indoor-outdoor temperature difference and CO2 concentration were highest when the air velocity was 4 m/s, suggesting that there is an optimal air velocity at which the air curtain can effectively suppress the airflow through the opening

The use of human mesenchymal stem cell-derived feeder cells for the cultivation of transplantable epithelial sheets. Investigative Ophthalmology and Visual

PURPOSE. To report the efficacy of human bone marrow-derived mesenchymal stem cells as a source of feeder cells for the cultivation of transplantable corneal epithelial cell sheets. METHODS. Human mesenchymal stem cells (marrow adherent stem cells; MASCs) were cultured in ␣-modified Eagle's medium with 10% serum and were treated with mitomycin C. Expression of cytokines in MASCs was confirmed by reverse transcription-polymerase chain reaction. Human limbal epithelial cells were cocultured with MASCs or 3T3 feeder cells to compare colony-forming efficiency (CFE). Limbal epithelial cells were cultured on MASCs or 3T3 feeder cells at the airliquid interface to allow stratification, and stratified epithelial sheets were analyzed by immunohistochemistry against cytokeratin 3 (K3), K15, p63␣, and ABCG2. Rabbit limbal epithelial cell sheets were cultivated with MASC feeder cells and transplanted to the ocular surface of the limbal-deficient rabbits. Epithelial grafts were observed by slit lamp microscopy for 4 weeks and then evaluated by histology and immunohistochemistry against K3 and K4. RESULTS. MASC feeder cells expressed keratinocyte growth factor, hepatocyte growth factor, and N-cadherin. The CFE of human limbal epithelial cells was similar in MASC and 3T3 feeder groups. Stratified cell sheets were successfully cultivated with MASC feeder cells expressing K3, K15, p63␣, and ABCG2. Transplanted epithelial sheets regenerated the corneal phenotype in limbal-deficient rabbits. CONCLUSIONS. MASC-derived feeder cells are suitable for the engineering of epithelial sheets, avoiding the use of potentially hazardous xenologic feeder cells. (Invest Ophthalmol Vis Sci