• Title/Summary/Keyword: Laser Head

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Chitosan/hydroxyapatite composite coatings on porous Ti6Al4V titanium implants: in vitro and in vivo studies

  • Zhang, Ting;Zhang, Xinwei;Mao, Mengyun;Li, Jiayi;Wei, Ting;Sun, Huiqiang
    • Journal of Periodontal and Implant Science
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    • v.50 no.6
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    • pp.392-405
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    • 2020
  • Purpose: Titanium implants are widely used in the treatment of dentition defects; however, due to problems such as osseointegration failure, peri-implant bone resorption, and periimplant inflammation, their application is subject to certain restrictions. The surface modification of titanium implants can improve the implant success rate and meet the needs of clinical applications. The goal of this study was to evaluate the effect of the use of porous titanium with a chitosan/hydroxyapatite coating on osseointegration. Methods: Titanium implants with a dense core and a porous outer structure were prepared using a computer-aided design model and selective laser sintering technology, with a fabricated chitosan/hydroxyapatite composite coating on their surfaces. In vivo and in vitro experiments were used to assess osteogenesis. Results: The quasi-elastic gradient and compressive strength of porous titanium implants were observed to decrease as the porosity increased. The in vitro experiments demonstrated that, the porous titanium implants had no biological toxicity; additionally, the porous structure was shown to be superior to dense titanium with regard to facilitating the adhesion and proliferation of osteoblast-like MC3T3-E1 cells. The in vivo experimental results also showed that the porous structure was beneficial, as bone tissue could grow into the pores, thereby exhibiting good osseointegration. Conclusions: Porous titanium with a chitosan/hydroxyapatite coating promoted MC3T3-E1 cell proliferation and differentiation, and also improved osseointegration in vitro. This study has meaningful implications for research into ways of improving the surface structures of implants and promoting implant osseointegration.

A Study on a Mask R-CNN-Based Diagnostic System Measuring DDH Angles on Ultrasound Scans (다중 트레이닝 기법을 이용한 MASK R-CNN의 초음파 DDH 각도 측정 진단 시스템 연구)

  • Hwang, Seok-Min;Lee, Si-Wook;Lee, Jong-Ha
    • Journal of the Institute of Convergence Signal Processing
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    • v.21 no.4
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    • pp.183-194
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    • 2020
  • Recently, the number of hip dysplasia (DDH) that occurs during infant and child growth has been increasing. DDH should be detected and treated as early as possible because it hinders infant growth and causes many other side effects In this study, two modelling techniques were used for multiple training techniques. Based on the results after the first transformation, the training was designed to be possible even with a small amount of data. The vertical flip, rotation, width and height shift functions were used to improve the efficiency of the model. Adam optimization was applied for parameter learning with the learning parameter initially set at 2.0 x 10e-4. Training was stopped when the validation loss was at the minimum. respectively A novel image overlay system using 3D laser scanner and a non-rigid registration method is implemented and its accuracy is evaluated. By using the proposed system, we successfully related the preoperative images with an open organ in the operating room

A Study on Improvement of Submarine Attack Periscope Operation Performance using Installing Protector on Sail (잠수함 공격잠망경 함교 보호구조물 설치를 통한 장비 운용성능 향상에 관한 연구)

  • Choi, Woo-Seok;Chang, Ho-Seong;Lee, Young-Suk;Kim, Sang-Il
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.22 no.5
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    • pp.199-206
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    • 2021
  • This paper describes the feasibility and reliability verification of installing a protective structure to protect attack periscopes. The attack periscope is the critical equipment of a submarine to enable the user to monitor surface and air activity, collect navigational data, and detect and identify targets. The attack periscope provides target information acquired through TV, IR camera, and laser range finder to the combat system. In the product improvement program, the upper part of the masts was exposed to the outside of the sail because the existing attack periscope was replaced with a new one. On the other hand, the head sensor can be damaged by floating objects, such as fishing nets, during sea navigation. Therefore, the installation of a protective structure for an attack periscope improved the equipment operation performance. The feasibility and reliability of the installation of the protective structure were verified by examining the influence of URN.

Patient Setup Aid with Wireless CCTV System in Radiation Therapy (무선 CCTV 시스템을 이용한 환자 고정 보조기술의 개발)

  • Park, Yang-Kyun;Ha, Sung-Whan;Ye, Sung-Joon;Cho, Woong;Park, Jong-Min;Park, Suk-Won;Huh, Soon-Nyung
    • Radiation Oncology Journal
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    • v.24 no.4
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    • pp.300-308
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    • 2006
  • $\underline{Purpose}$: To develop a wireless CCTV system in semi-beam's eye view (BEV) to monitor daily patient setup in radiation therapy. $\underline{Materials\;and\;Methods}$: In order to get patient images in semi-BEV, CCTV cameras are installed in a custom-made acrylic applicator below the treatment head of a linear accelerator. The images from the cameras are transmitted via radio frequency signal (${\sim}2.4\;GHz$ and 10 mW RF output). An expected problem with this system is radio frequency interference, which is solved utilizing RF shielding with Cu foils and median filtering software. The images are analyzed by our custom-made software. In the software, three anatomical landmarks in the patient surface are indicated by a user, then automatically the 3 dimensional structures are obtained and registered by utilizing a localization procedure consisting mainly of stereo matching algorithm and Gauss-Newton optimization. This algorithm is applied to phantom images to investigate the setup accuracy. Respiratory gating system is also researched with real-time image processing. A line-laser marker projected on a patient's surface is extracted by binary image processing and the breath pattern is calculated and displayed in real-time. $\underline{Results}$: More than 80% of the camera noises from the linear accelerator are eliminated by wrapping the camera with copper foils. The accuracy of the localization procedure is found to be on the order of $1.5{\pm}0.7\;mm$ with a point phantom and sub-millimeters and degrees with a custom-made head/neck phantom. With line-laser marker, real-time respiratory monitoring is possible in the delay time of ${\sim}0.17\;sec$. $\underline{Conclusion}$: The wireless CCTV camera system is the novel tool which can monitor daily patient setups. The feasibility of respiratory gating system with the wireless CCTV is hopeful.

Verification of Target Position in Stereotactic Radiosurgery Based on Photon Knife System (Photon Knife 시스템에 근거한 뇌정위 방사선수술에서 표적위치 확인)

  • 최태진;김진희;김옥배
    • Progress in Medical Physics
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    • v.14 no.2
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    • pp.99-107
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    • 2003
  • This study was performed to prepare the verification film for localizing beam-target position with the Photon Knife radiosurgery system (PKRS) using linear accelerator(Mitsubishi, Model ML-15MDX). We developed a laser calibration system using a reticle of transparent lucite to detect Inlet and outlet beams. We verified fixation of the second collimator with film mounted on a holder in the shape of an octagon block 5cm apart from the isocenter. The film was exposed to photon beams of linear accelerator at an interval of 45 degrees during the gantry movement. There were no shifts in the beam of the second collimator during gantry movement. We used a position marker which is designed a head-shaped small lead block and a 10 mm in diameter of steel bead in the plastic tube. The position marker helped to verify the beam directions with patient position in multi-arc and trans-multi-arc of PKRS The verification of beam alignments showed an average 0.8$\pm$0.26 mm discrepancy in LINAC-gram images of PKRS. In our study, the couch movement was $\pm$5 mm laterally, while it shook $\pm$ 2 mm toward the couch axis. The couch, however, was immediately returned to the initial site after shaking. Thus, we postulate that the beam-target position(s) should be verified with LINAC-gram in a stereotactic radiosurgery system to achieve the accuracy of beam-target alignment.

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Sclerotherapy of Multiple Intraoral Venous Malformations with Use of Ethanolamine Oleate: A Case Report (구강내 발생한 다발성 정맥기형 병소에의 Ethanolamine Oleate 경화제 주사 후 치험례)

  • Kim, Tae-Kwang;Yang, Jae-Young;Choi, Seok-Tai;Jeon, Hee-Kyung;Leem, Dae-Ho;Baek, Jin-A;Shin, Hyo-Keun;Ko, Seung-O
    • Maxillofacial Plastic and Reconstructive Surgery
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    • v.34 no.6
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    • pp.488-493
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    • 2012
  • Hemangioma and vascular malformation are the most common benign tumors that are caused by congenitally or traumatic events. Theses tumors represent approximately 1/3~1/4 of all hemangiomas and vascular malformations in the head and neck. There are many forms of treatment for hemangioma and vascular malformation including closed observation, surgery, radiotherapy, laser therapy, steroid therapy, compression, embolization, and sclerotherapy. Ethanolamine oleate is an unsaturated fatty acid salt that has been used as a sclerosing agent because of its excellent thrombosing properties. This paper presents 1 case of intraoral multiple venous malformations treatment with 1.25% ethanolamine oleate (3.6~9.6 mg dose) intralesionally injected for 6 to 14 weeks over 2 week intervals. After the sclerotherapy, lesions almost completely disappeared without side effects. In conclusion, sclerotherapy using ethanolamine oleate is very effective against venous malformations, and sufficiently provides alternative support for surgical and other methods.

Effect of Tinnitus after Bleeding, Acupuncture, Moxa, and Laser treatment (부황, 뜸, 침 레이저요법 시술이 耳鳴에 미치는 영향)

  • Park, Gyung-hwa;Han, Young-mok;Ahn, Soo-Hyun;Hwang, Chung-yeon
    • The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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    • v.12 no.1
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    • pp.396-407
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    • 1999
  • Although tinnitus is a common disease, it's reason, pathogenesis and treatment are not examined clearly. As tinnitus is a subjective complaint, it is not easy to evaluate objectively and to compare with another. In this study, we intend to estimate the effect of a variety of oriental medical treatments to tinnitus. We inquired about 30cases of tinnitus patients visited the Kwang-ju Oriental Medical Hospital of Wonkwang University from Apr. 1998 to Sep. 1998. We examined the 30cases in the view of sex, age, occupation, duration, etiologic factors, past history, associating symptoms, quality of tinnitus, and recovery rate after treatments. The results were as follows: 1. In distribution of sex, the ratio of male was $63.3\%$(19cases)and\;female\;was\;36.6\%$(11cases). 2. In distribution of age, the ratio of the 2th decade was $6.6\%(2cases),\;the\;3th\;decade\;was\;20.0\%(6cases),\;the\;4th\;decade\;was\;16.6\%(5cases),\;the\;5th\;decade\;was\;23.3\%(7cases),\;the\;6th\;decade\;was\;30.0\%\;(9cases),and\;the\;7th\;decade\;was\;3.3\%(1case)$. 3. In distribution of occupation, the ratio of employee was $23.3\%$(7cases), house-keeper was $63.3\%(11cases),\;farmer\;was\;16.6\%(5cases),\;teacher\;was\;13.3\%$ (4cases), and student, merchant, soldier was each $3.3\%$(1case). 4. In distribution of duration, the ratio of under 1month was $6.6\%$ (2cases), 1 month -6 months was $20.0\%$(6cases), 6 months- 12months was $30.0\%$(9cases), 12months-36months was $23.3\%$(7cases), and over 36months was $20.0\%$(6cases). 5. In etiologic factor of tinnitus, the ratio of unknown reason was $40.0\%$ (12cases), overwork was $16.6\%$(5cases), emotional stress was $10.0\%$(3cases), noise was $6.6\%$(2cases), cases of laying overwork upon stress was $13.3\%$(4cases), head trauma was $3.3\%$(1case), gun report was $3.3\%$ (1case), and after sickness was $6.6\%$(2cases). 6. 9 cases had experienced such a disease as meniere's disease, tympanitis, labyrinthitis, trauma of tympanum, hypertension, etc. 7. Commonly associated symptoms were dizziness, deafness, uneasiness, headache, ear fullness, fatigue, insomnia, nausea, vomiting, and forgetfulness. 8. Most frequent quality of tinnitus were buzzing, whistling, humming etc. 9. In $76.6\%$(23cases) of tinnitus patients, it was improved, but in $23.3%$(7cases) of them, not improved. Total recovery rate was $42.2\%$.

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Relationship between Breathing Pattern Disorder and Joint Position Sense in Patients with Chronic Low Back Pain (만성요통환자의 호흡패턴이상과 관절위치감각의 관계)

  • Cho, Byungyun;Yoon, Junggyu
    • Journal of The Korean Society of Integrative Medicine
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    • v.7 no.2
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    • pp.1-10
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    • 2019
  • Purpose : To investigate the relationship between breathing pattern disorder and joint position error (JPE) in patients with chronic low back pain (CLBP). Methods : Thirty nine patients with CLBP participated. End-tidal $CO_2$ and respiration rate (RR) were measured using a capnography. Breathing-hold time (BHT) and Nijmegen Questionnaire (NQ) were investigated. Thoracic excursion was measured with a cloth tape measurement technique. Joint position error were measured using a small laser point mounted on a lightweight headband. they were asked to relocate the head, after the neck movement on the horizontal plane. Pearson 's test was used for correlation analysis between respiratory variables and JPE in patients with CLBP. Independent t-test was used to verify the difference between thoracic and diaphragm breathing pattern in patients with CLBP. The significance level was set at 0.05. Results : There was a significant correlation between JPE (LR) and JPE (RR, EX) (r=.639, r=.813) (p<.001) and a low negative correlation with end-tidal $CO_2$ (r=-.357) (p<.05). There was a significant correlation between RR and JPE (EX) (r=.750) (p<.001). There was a low correlation between JPE (EX) and NQ (r=.333) (p<.05). There was a somewhat high negative correlation between NQ and thoracic excursion (r=-.528) (p<.001). There was a somewhat high negative correlation between thoracic excursion and JPE (LR, RR, EX) (r=-.470, r=-.484, r=-.602) (p<.001). There were no significant differences in the RR, BHT, NQ, and thoracic excursion between the thoracic and diaphragmatic breathing (p>.05). There was a significant difference in the JPE (EX), end - tidal $CO_2$, and VAS values between the thoracic and diaphragm breathing (p<.05). Conclusion : There was a correlation between JPE (EX) and NQ in patients with CLBP, and correlation between thoracic excursion and JPE (LR, RR, EX) and NQ. There was a significant difference in the JPE (EX), end-tidal $CO_2$ level, and VAS value in the comparison of thoracic breathing and diaphragm breathing. The results showed that breathing patterns and JPE were related to each other.

Xiang Study: an association of breastmilk composition with maternal body mass index and infant growth during the first 3 month of life

  • Peng, Xuyi;Li, Jie;Yan, Shuyuan;Chen, Juchun;Lane, Jonathan;Malard, Patrice;Liu, Feitong
    • Nutrition Research and Practice
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    • v.15 no.3
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    • pp.367-381
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    • 2021
  • BACKGROUND/OBJECTIVES: This study aimed to establish a mother and child cohort in the Chinese population, and investigate human breastmilk (HBM) composition and its relationship with maternal body mass index (BMI) and infant growth during the first 3 mon of life. SUBJECTS/METHODS: A total of 101 Chinese mother and infant pairs were included in this prospective cohort. Alterations in the milk macronutrients of Chinese mothers at 1 mon (T1), 2 mon (T2), and 3 mon (T3) lactation were analyzed. HBM fatty acid (FA) profiles were measured by gas chromatography (GC), and HBM proteomic profiling was achieved by matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry (MS). RESULTS: During the first 3 mon of lactation (P < 0.05), significant decreases were determined in the levels of total energy, fat, protein, and osteopontin (OPN), as well as ratios of long-chain saturated FA (including C16:0, C22:0 and C24:0), monounsaturated FA (including C16:1), and n-6 poly unsaturated FA (PUFA) (including C20:3n-6 and C20:4n-6, and n-6/n-3). Conversely, butyrate, C6:0 and n-3 PUFA C18:3n-3 (α-linolenic acid, ALA) were significantly increased during the first 3 mon (P < 0.05). HBM proteomic analyses distinguished compositional protein differences over time (P = 0.001). Personalized motherinfant analyses demonstrated that HBM from high BMI mothers presented increased total energy, fat, protein and OPN, and increased content of n-6 PUFA (including C18:3n-6, C20:3n-6 and n-6/n-3 ratio) as compared with low BMI mothers (P < 0.05). Furthermore, BMI of the mothers positively correlated with the head circumference (HC) of infants as well as the specific n-6 PUFA C20:3n-6 over the 3 time points examined. Infant HC was negatively associated with C18:0. CONCLUSION: This study provides additional evidence to the Chinese HBM database, and further knowledge of FA function. It also helps to establish future maternal strategies that support the healthy growth and development of Chinese infants.

GafChromic Film Dosimetry for Stereotactic Radiosurgery with a Linear Accelerator (선형가속기를 이용한 정위방사선 치료 시 GafChromic Film을 이용한 선량측정)

  • Han Seung Hee;Cho Byung Chul;Park Suk Won;Oh Do Hoon;Park Hee Chul;Bae Hoon Sik
    • Radiation Oncology Journal
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    • v.21 no.2
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    • pp.167-173
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    • 2003
  • Purpose: The purpose of this study was to evaluate whether a GafChromic film applied to stereotactic radiosurgery with a linear accelerator could provide information on the value for acceptance testing and quality control on the absolute dose and relative dose measurements and/or calculation of treatment planning system. Materials and methods: A spherical acrylic phantom, simulating a patient's head, was constructed from three points. The absolute and relative dose distributions could be measured by inserting a GafChromic film into the phantom. We tested the use of a calibrated GafChromic film (MD-55-2, Nuclear Associate, USA) for measuring the optical density. These measurements were achieved by irradiating the films with a dose of 0-112 Gy employing 6 MV photon. To verify the accuracy of the prescribed dose delivery to a target isocenter using a five arc beams (irradiated in 3 Gy per one beam) setup, calculated by the Linapel planning system the absolute dose and relative dose distribution using a GafChromic film were measured. All the irradiated films were digitized with a Lumiscan 75 laser digitizer and processed with the RIT113 film dosimetry system. Results: We verified the linearity of the Optical Density of a MD-55-2 GafChromic film, and measured the depth dose profile of the beam. The absolute dose delivered to the target was close to the prescribed dose of Linapel within an accuracy for the GafChromic film dosimetry (of $\pm$3$\%$), with a measurement uncertainty of $\pm$1 mm for the 50$\~$90$\%$ isodose lines. Conclusion: Our results have shown that the absolute dose and relative dose distribution curves obtained from a GafChromic film can provide information on the value for acceptance. To conclude the GafChromic flim is a convenient and useful dosimetry tool for linac based radiosurgery.