歯根をトルク移動する際に生じる応力

舌側に転位した側切歯を歯体移動させるには，歯冠を唇側に傾斜移動した後，舌側にある歯根を唇側移動させる必要がある。その際，歯根およびその周囲組織にはトルク力が生じており，このトルクコントロールを適切に行うことが歯科矯正臨床上きわめて重要である。本研究では，舌側転位した右側上顎側切歯の歯根を唇側移動する際に側切歯および両隣在歯に生じる応力について有限要素解析を行った。上顎右側中切歯から犬歯の歯列モデルは頭蓋骨モデル（ニッシン）のCT 画像を，0.018”×0.025”スロットブラケットおよび0.018”×0.025”ステンレススチールワイヤーについては3 次元CAD データをもとに，3 次元有限要素モデルを構築した。荷重条件として，ワイヤーの側切歯部分に6°のリンガルクラウントルクを負荷した。その結果，側切歯に生じるvon Mises 相当応力の大きさは約11.0×10−3 MPa であり，唇側歯頸部および根尖部に集中していた。一方，両隣在歯には，最大で約4.5×10−3 MPa のvon Mises 相当応力が根尖部および舌側歯頸部に認められた。本研究結果より，舌側転位した上顎側切歯の歯根を唇側移動する際にはリンガルクラウントルク負荷によって当該歯ならびに隣在歯に生じる作用・反作用を考慮し，歯の移動を行う必要が示唆された。In case of lingual displacement of lateral incisor, we should apply labial root torque after labial tipping movement of lateral incisor. The torque moment generated by third order bend is one of the important keys for orthodontic tooth movement. The objective of this study was to investigate the stress distribution on root surface and in surround periodontal ligament (PDL) when labial root torque is applied to lingually displaced lateral incisor by finite element (FE) analysis. The FE models of maxillary incisors and canine were developed from three-dimensional (3 D) point data sets of CT-image. The models of 0.018” slot sizes stainless steel brackets and 0.018 x 0.025-inch stainless steel (SS) wires were constructed based on 3 D CAD data. As a loading condition, 6 degrees labial root torque moment was applied to the archwire at lateral incisor. The distribution of the von Mises equivalent stresses (equivalent stress) on the root surface and in surrounding PDL of incisors and canine was evaluated using an FE analysis. When applying labial root torque at lateral incisor, greater equivalent stress was observed at the labial cervical margin and root apex. The values of equivalent stresses on the root surface of lateral incisor were less than 11.0 × 10-3 MPa, while the maximum equivalent stress of the neighboring teeth (central incisor and canine) were 4.5 × 10-3 observed at the lingual cervical margin and root apex. These results indicate the neighboring teeth are considerably affected as a reaction force when the torque moment is applied to the targeted tooth

Heterogeneous Nucleation of Protein Crystals on Fluorinated Layered Silicate

Here, we describe an improved system for protein crystallization based on heterogeneous nucleation using fluorinated layered silicate. In addition, we also investigated the mechanism of nucleation on the silicate surface. Crystallization of lysozyme using silicates with different chemical compositions indicated that fluorosilicates promoted nucleation whereas the silicates without fluorine did not. The use of synthesized saponites for lysozyme crystallization confirmed that the substitution of hydroxyl groups contained in the lamellae structure for fluorine atoms is responsible for the nucleation-inducing property of the nucleant. Crystallization of twelve proteins with a wide range of pI values revealed that the nucleation promoting effect of the saponites tended to increase with increased substitution rate. Furthermore, the saponite with the highest fluorine content promoted nucleation in all the test proteins regardless of their overall net charge. Adsorption experiments of proteins on the saponites confirmed that the density of adsorbed molecules increased according to the substitution rate, thereby explaining the heterogeneous nucleation on the silicate surface

Sequential therapies after atezolizumab plus bevacizumab or lenvatinib first-line treatments in hepatocellular carcinoma patients

Introduction: The aim of this retrospective proof-of-concept study was to compare different second-line treatments for patients with hepatocellular carcinoma and progressive disease (PD) after first-line lenvatinib or atezolizumab plus bevacizumab.Materials and methods: A total of 1381 patients had PD at first-line therapy. 917 patients received lenvatinib as first-line treatment, and 464 patients atezolizumab plus bevacizumab as first-line.Results: 49.6% of PD patients received a second-line therapy without any statistical difference in overall survival (OS) between lenvatinib (20.6 months) and atezolizumab plus bev-acizumab first-line (15.7 months; p = 0.12; hazard ratio [HR] = 0.80). After lenvatinib first-line, there wasn't any statistical difference between second-line therapy subgroups (p = 0.27; sorafenib HR: 1; immunotherapy HR: 0.69; other therapies HR: 0.85). Patients who under-went trans-arterial chemo-embolization (TACE) had a significative longer OS than patients who received sorafenib (24.7 versus 15.8 months, p < 0.01; HR = 0.64). After atezolizumab plus bevacizumab first-line, there was a statistical difference between second-line therapy subgroups (p < 0.01; sorafenib HR: 1; lenvatinib HR: 0.50; cabozantinib HR: 1.29; other therapies HR: 0.54). Patients who received lenvatinib (17.0 months) and those who under-went TACE (15.9 months) had a significative longer OS than patients treated with sorafenib (14.2 months; respectively, p = 0.01; HR = 0.45, and p < 0.05; HR = 0.46).Conclusion: Approximately half of patients receiving first-line lenvatinib or atezolizumab plus bevacizumab access second-line treatment. Our data suggest that in patients progressed to atezolizumab plus bevacizumab, the systemic therapy able to achieve the longest survival is lenvatinib, while in patients progressed to lenvatinib, the systemic therapy able to achieve the longest survival is immunotherapy

<所内学術研究成果報告>H. 「環境保全・地球環境温暖化防止をターゲットとする新パルプ資源ケナフの栽培と利用に関する研究」

本研究は, エコマテリアルとしての非木材繊維資源に最も適切である一年生植物ケナフ(Hibiscus cannabinus L.)の栽培とその利用を目的に, 1993年より開始した研究である。従来の成果は, すでに本年報1992,\u2794,\u2795,\u2796,\u2797,\u2798,および\u2799年に報告した。特に従来のケナフ栽培の成果の総決算として, 1998年より平塚市および平塚ケナフ普及協会との共同研究が行われてきた。特に, 平塚市では休耕田対策としてケナフの栽培を推奨し, 現在, 栽培したケナフのパルプ化と紙製造を行って市政に還元している。この現状はさらに展開し, 平塚市のみならず日本全国にその輪が広がり大きな活動となっている。これらの栽培や利用は最も基礎的な指導と, より学術的な研究成果の提供が常に必要であり, この点を最も重要な課題としている。さらに, 環境教育に対する展開を学校, 公民館などを中心に行い, 2000年度は, 平塚キャンパスで市内6小学校の生徒28名のケナフ教育を行った。まお, 研究室内では, 栽培研究の他に, a)種子の発芽阻害実験, b)海水による阻害実験, c)生長に伴うクロロフィル量および水分量の測定実験, d)光合成測定実験, e)花の成分(色素)研究, f)葉など各器官の成分研究などを行っている。取り扱った種類も, ローゼル(H. sabdariffa L.)類も加えると30種に近い

First Fabrication of GaInAs/InP Buried Metal Heterojunction Bipolar Transistor and Reduction of Base-Collector Capacitance

We report a novel approach for improving the performance of InP-based heterojunction bipolar transistors (HBTs). A buried-metal heterojunction bipolar transistor (BM-HBT), in which tungsten stripes of the same area as the emitter metal were buried in an i-InP collector layer, was fabricated for the first time. The aim in fabricating this structure is to realize a reduction in the total base-collector capacitance (C BCT ). In the measurement of microwave S-parameters, C BCT of 10.3 fF was evaluated. The effective base-collector junction area of the BM-HBT was estimated to be 22% that of conventional-HBT considering the difference in collector thickness

Planning Walking Patterns for a Biped Robot

Biped robots have better mobility than conventional wheeled robots, but they tend to tip over easily. To be able to walk stably in various environments, such as on rough terrain, up and down slopes, or in regions containing obstacles, it is necessary for the robot to adapt to the ground conditions with a foot motion, and maintain its stability with a torso motion. When the ground conditions and stability constraint are satisfied, it is desirable to select a walking pattern that requires small torque and velocity of the joint actuators. In this paper, we first formulate the constraints of the foot motion parameters. By varying the values of the constraint parameters, we can produce different types of foot motion to adapt to ground conditions. We then propose a method for formulating the problem of the smooth hip motion with the largest stability margin using only two parameters, and derive the hip trajectory by iterative computation. Finally, the correlation between the actuator specifications and the walking patterns is described through simulation studies, and the effectiveness of the proposed methods is confirmed by simulation examples and experimental results

Photodynamic Diagnosis Using 5-Aminolevulinic Acid with a Novel Compact System and Chromaticity Analysis for the Detection of Oral Cancer and High-Risk Potentially Malignant Oral Disorders

Detecting early-stage oral cancer and precancerous lesions are critical to improving patient prognosis and quality of life after treatment. Photodynamic diagnosis using 5-aminolevulinic acid enables the detection of malignant lesions. This study aimed to improve the diagnostic accuracy of photodynamic diagnosis using an objective chromaticity analysis of fluorescence emitted from oral lesions. Sixty-seven patients with clinically suspicious oral cavity lesions underwent photodynamic diagnosis after topical application of 5-aminolevulinic acid solution, followed by imaging and histological evaluation of the lesions. Chromaticity red and green values were measured from the fluorescence images on the lesion, and the red-to-green ratio was calculated. The photodynamic diagnosis allowed for the visualization of oral cancer and high-risk dysplasia as red fluorescence. Compared to low-risk dysplasia and benign lesions, oral cancer and high-risk dysplasia areas had a significantly higher red value and red-to-green ratio. After setting the cutoff value, sensitivity and specificity were 83.3–88.7% and 83.3–83.9%, respectively, when discriminating between oral cancer or high-risk dysplasia and low-risk dysplasia or benign lesions. Photodynamic diagnosis combined with chromaticity analysis may be a valuable diagnostic tool for detecting oral lesions, with a high likelihood of malignant transformation