An Outdoor Navigation Platform with a 3D Scanner and Gyro-assisted Odometry
NASA Astrophysics Data System (ADS)
Yoshida, Tomoaki; Irie, Kiyoshi; Koyanagi, Eiji; Tomono, Masahiro
This paper proposes a light-weight navigation platform that consists of gyro-assisted odometry, a 3D laser scanner and map-based localization for human-scale robots. The gyro-assisted odometry provides highly accurate positioning only by dead-reckoning. The 3D laser scanner has a wide field of view and uniform measuring-point distribution. The map-based localization is robust and computationally inexpensive by utilizing a particle filter on a 2D grid map generated by projecting 3D points on to the ground. The system uses small and low-cost sensors, and can be applied to a variety of mobile robots in human-scale environments. Outdoor navigation experiments were conducted at the Tsukuba Challenge held in 2009 and 2010, which is an open proving ground for human-scale robots. Our robot successfully navigated the assigned 1-km courses in a fully autonomous mode multiple times.
NASA Astrophysics Data System (ADS)
Antony, R.; Moliton, A.; Ratier, B.
1998-06-01
Light emitting diode based on the structure ITO/Alq3/Ca-Al lead to enhanced quantum efficiency when the Alq3 active layer is obtained by IBAD (Ion Beam Assisted Deposition): with Iodine ions, the optimization (quantum efficiency multiplied by a factor10) is obtained for an ion energy equal to 100eV. La réalisation de diodes électroluminescentes basées sur la structure ITO/Alq3/Ca-Al conduit à des performances améliorées lorsque le dépôt de la couche active Alq3 est effectué avec l'assistance d'un faisceau d'ions; l'optimisation (rendement quantique interne accru d'un ordre de grandeur) correspond à des ions Iode d'énergie 100eV.
Cabri 3D - assisted collaborative learning to enhance junior high school students’ spatial ability
NASA Astrophysics Data System (ADS)
Muntazhimah; Miatun, A.
2018-01-01
The main purpose of this quasi-experimental study was to determine the enhancement of spatial ability of junior high school students who learned through Cabri-3D assisted collaborative learning. The methodology of this study was the nonequivalent group that was conducted to students of the eighth grade in a junior high school as a population. Samples consisted one class of the experimental group who studied with Cabri-3D assisted collaborative learning and one class as a control group who got regular learning activity. The instrument used in this study was a spatial ability test. Analyzing normalized gain of students’ spatial ability based on mathemathical prior knowledge (MPK) and its interactions was tested by two-way ANOVA at a significance level of 5% then continued with using Post Hoc Scheffe test. The research results showed that there was significant difference in enhancement of the spatial ability between students who learnt with Cabri 3D assisted collaborative learning and students who got regular learning, there was significant difference in enhancement of the spatial ability between students who learnt with cabri 3D assisted collaborative learning and students who got regular learning in terms of MPK and there is no significant interaction between learning (Cabri-3D assisted collaborative learning and regular learning) with students’ MPK (high, medium, and low) toward the enhancement of students’ spatial abilities. From the above findings, it can be seen that cabri-3D assisted collaborative learning could enhance spatial ability of junior high school students.
Actuator-Assisted Calibration of Freehand 3D Ultrasound System.
Koo, Terry K; Silvia, Nathaniel
2018-01-01
Freehand three-dimensional (3D) ultrasound has been used independently of other technologies to analyze complex geometries or registered with other imaging modalities to aid surgical and radiotherapy planning. A fundamental requirement for all freehand 3D ultrasound systems is probe calibration. The purpose of this study was to develop an actuator-assisted approach to facilitate freehand 3D ultrasound calibration using point-based phantoms. We modified the mathematical formulation of the calibration problem to eliminate the need of imaging the point targets at different viewing angles and developed an actuator-assisted approach/setup to facilitate quick and consistent collection of point targets spanning the entire image field of view. The actuator-assisted approach was applied to a commonly used cross wire phantom as well as two custom-made point-based phantoms (original and modified), each containing 7 collinear point targets, and compared the results with the traditional freehand cross wire phantom calibration in terms of calibration reproducibility, point reconstruction precision, point reconstruction accuracy, distance reconstruction accuracy, and data acquisition time. Results demonstrated that the actuator-assisted single cross wire phantom calibration significantly improved the calibration reproducibility and offered similar point reconstruction precision, point reconstruction accuracy, distance reconstruction accuracy, and data acquisition time with respect to the freehand cross wire phantom calibration. On the other hand, the actuator-assisted modified "collinear point target" phantom calibration offered similar precision and accuracy when compared to the freehand cross wire phantom calibration, but it reduced the data acquisition time by 57%. It appears that both actuator-assisted cross wire phantom and modified collinear point target phantom calibration approaches are viable options for freehand 3D ultrasound calibration.
Actuator-Assisted Calibration of Freehand 3D Ultrasound System
2018-01-01
Freehand three-dimensional (3D) ultrasound has been used independently of other technologies to analyze complex geometries or registered with other imaging modalities to aid surgical and radiotherapy planning. A fundamental requirement for all freehand 3D ultrasound systems is probe calibration. The purpose of this study was to develop an actuator-assisted approach to facilitate freehand 3D ultrasound calibration using point-based phantoms. We modified the mathematical formulation of the calibration problem to eliminate the need of imaging the point targets at different viewing angles and developed an actuator-assisted approach/setup to facilitate quick and consistent collection of point targets spanning the entire image field of view. The actuator-assisted approach was applied to a commonly used cross wire phantom as well as two custom-made point-based phantoms (original and modified), each containing 7 collinear point targets, and compared the results with the traditional freehand cross wire phantom calibration in terms of calibration reproducibility, point reconstruction precision, point reconstruction accuracy, distance reconstruction accuracy, and data acquisition time. Results demonstrated that the actuator-assisted single cross wire phantom calibration significantly improved the calibration reproducibility and offered similar point reconstruction precision, point reconstruction accuracy, distance reconstruction accuracy, and data acquisition time with respect to the freehand cross wire phantom calibration. On the other hand, the actuator-assisted modified “collinear point target” phantom calibration offered similar precision and accuracy when compared to the freehand cross wire phantom calibration, but it reduced the data acquisition time by 57%. It appears that both actuator-assisted cross wire phantom and modified collinear point target phantom calibration approaches are viable options for freehand 3D ultrasound calibration. PMID:29854371
Fabrication of tough epoxy with shape memory effects by UV-assisted direct-ink write printing.
Chen, Kaijuan; Kuang, Xiao; Li, Vincent; Kang, Guozheng; Qi, H Jerry
2018-03-07
3D printing of epoxy-based shape memory polymers with high mechanical strength, excellent thermal stability and chemical resistance is highly desirable for practical applications. However, thermally cured epoxy in general is difficult to print directly. There have been limited numbers of successes in printing epoxy but they suffer from relatively poor mechanical properties. Here, we present an ultraviolet (UV)-assisted 3D printing of thermally cured epoxy composites with high tensile toughness via a two-stage curing approach. The ink containing UV curable resin and epoxy oligomer is used for UV-assisted direct-ink write (DIW)-based 3D printing followed by thermal curing of the part containing the epoxy oligomer. The UV curable resin forms a network by photo polymerization after the 1st stage of UV curing, which can maintain the printed architecture at an elevated temperature. The 2nd stage thermal curing of the epoxy oligomer yields an interpenetrating polymer network (IPN) composite with highly enhanced mechanical properties. It is found that the printed IPN epoxy composites enabled by the two-stage curing show isotropic mechanical properties and high tensile toughness. We demonstrated that the 3D-printed high-toughness epoxy composites show good shape memory properties. This UV-assisted DIW 3D printing via a two-stage curing method can broaden the application of 3D printing to fabricate thermoset materials with enhanced tensile toughness and tunable properties for high-performance and functional applications.
3D Game-Based Learning System for Improving Learning Achievement in Software Engineering Curriculum
ERIC Educational Resources Information Center
Su,Chung-Ho; Cheng, Ching-Hsue
2013-01-01
The advancement of game-based learning has encouraged many related studies, such that students could better learn curriculum by 3-dimension virtual reality. To enhance software engineering learning, this paper develops a 3D game-based learning system to assist teaching and assess the students' motivation, satisfaction and learning achievement. A…
Matrix-Assisted Three-Dimensional Printing of Cellulose Nanofibers for Paper Microfluidics.
Shin, Sungchul; Hyun, Jinho
2017-08-09
A cellulose nanofiber (CNF), one of the most attractive green bioresources, was adopted for construction of microfluidic devices using matrix-assisted three-dimensional (3D) printing. CNF hydrogels can support structures printed using CAD design in a 3D hydrogel environment with the appropriate combination of rheological properties between the CNF hydrogel and ink materials. Amazingly, the structure printed freely in the bulky CNF hydrogels was able to retain its highly resolved 3D features in an ultrathin two-dimensional (2D) paper using a simple drying process. The dimensional change in the CNF hydrogels from 3D to 2D resulted from simple dehydration of the CNFs and provided transparent, stackable paper-based 3D channel devices. As a proof of principle, the rheological properties of the CNF hydrogels, the 3D structure of the ink, the formation of channels by evacuation of the ink, and the highly localized selectivity of the devices are described.
UV-Assisted 3D Printing of Glass and Carbon Fiber-Reinforced Dual-Cure Polymer Composites
Invernizzi, Marta; Natale, Gabriele; Levi, Marinella; Turri, Stefano; Griffini, Gianmarco
2016-01-01
Glass (GFR) and carbon fiber-reinforced (CFR) dual-cure polymer composites fabricated by UV-assisted three-dimensional (UV-3D) printing are presented. The resin material combines an acrylic-based photocurable resin with a low temperature (140 °C) thermally-curable resin system based on bisphenol A diglycidyl ether as base component, an aliphatic anhydride (hexahydro-4-methylphthalic anhydride) as hardener and (2,4,6,-tris(dimethylaminomethyl)phenol) as catalyst. A thorough rheological characterization of these formulations allowed us to define their 3D printability window. UV-3D printed macrostructures were successfully demonstrated, giving a clear indication of their potential use in real-life structural applications. Differential scanning calorimetry and dynamic mechanical analysis highlighted the good thermal stability and mechanical properties of the printed parts. In addition, uniaxial tensile tests were used to assess the fiber reinforcing effect on the UV-3D printed objects. Finally, an initial study was conducted on the use of a sizing treatment on carbon fibers to improve the fiber/matrix interfacial adhesion, giving preliminary indications on the potential of this approach to improve the mechanical properties of the 3D printed CFR components. PMID:28773704
UV-Assisted 3D Printing of Glass and Carbon Fiber-Reinforced Dual-Cure Polymer Composites.
Invernizzi, Marta; Natale, Gabriele; Levi, Marinella; Turri, Stefano; Griffini, Gianmarco
2016-07-16
Glass (GFR) and carbon fiber-reinforced (CFR) dual-cure polymer composites fabricated by UV-assisted three-dimensional (UV-3D) printing are presented. The resin material combines an acrylic-based photocurable resin with a low temperature (140 °C) thermally-curable resin system based on bisphenol A diglycidyl ether as base component, an aliphatic anhydride (hexahydro-4-methylphthalic anhydride) as hardener and (2,4,6,-tris(dimethylaminomethyl)phenol) as catalyst. A thorough rheological characterization of these formulations allowed us to define their 3D printability window. UV-3D printed macrostructures were successfully demonstrated, giving a clear indication of their potential use in real-life structural applications. Differential scanning calorimetry and dynamic mechanical analysis highlighted the good thermal stability and mechanical properties of the printed parts. In addition, uniaxial tensile tests were used to assess the fiber reinforcing effect on the UV-3D printed objects. Finally, an initial study was conducted on the use of a sizing treatment on carbon fibers to improve the fiber/matrix interfacial adhesion, giving preliminary indications on the potential of this approach to improve the mechanical properties of the 3D printed CFR components.
3D force control for robotic-assisted beating heart surgery based on viscoelastic tissue model.
Liu, Chao; Moreira, Pedro; Zemiti, Nabil; Poignet, Philippe
2011-01-01
Current cardiac surgery faces the challenging problem of heart beating motion even with the help of mechanical stabilizer which makes delicate operation on the heart surface difficult. Motion compensation methods for robotic-assisted beating heart surgery have been proposed recently in literature, but research on force control for such kind of surgery has hardly been reported. Moreover, the viscoelasticity property of the interaction between organ tissue and robotic instrument further complicates the force control design which is much easier in other applications by assuming the interaction model to be elastic (industry, stiff object manipulation, etc.). In this work, we present a three-dimensional force control method for robotic-assisted beating heart surgery taking into consideration of the viscoelastic interaction property. Performance studies based on our D2M2 robot and 3D heart beating motion information obtained through Da Vinci™ system are provided.
Ma, Fangwei; Ma, Di; Wu, Guang; Geng, Weidan; Shao, Jinqiu; Song, Shijiao; Wan, Jiafeng; Qiu, Jieshan
2016-05-10
A smart and sustainable strategy based on charge-induced self-assembly and nanocrystal-assisted catalytic graphitization is explored for the efficient construction of 3D nanostructure hierarchical porous graphitic carbons from the pectin biopolymer. The electrostatic interaction between the negatively charged pectin chains and magnesium ions plays a crucial role in the formation of 3D architectures. The 3D HPGCs possess a three-dimensional carbon framework with a hierarchical porous structure, flake-like graphitic carbon walls and high surface area (1320 m(2) g(-1)). The 3D HPGCs show an outstanding specific capacitance of 274 F g(-1) and excellent rate capability with a high capacitance retention of 85% at a high current density of 50 A g(-1) for supercapacitor electrodes. This strategy provided a novel approach to effectively construct 3D porous carbon nanostructures from biopolymers.
Fu, Xi; Qiao, Jia; Girod, Sabine; Niu, Feng; Liu, Jian Feng; Lee, Gordon K; Gui, Lai
2017-09-01
Mandible contour surgery, including reduction gonioplasty and genioplasty, has become increasingly popular in East Asia. However, it is technically challenging and, hence, leads to a long learning curve and high complication rates and often needs secondary revisions. The increasing use of 3-dimensional (3D) technology makes accurate single-stage mandible contour surgery with minimum complication rates possible with a virtual surgical plan (VSP) and 3-D surgical templates. This study is to establish a standardized protocol for VSP and 3-D surgical templates-assisted mandible contour surgery and evaluate the accuracy of the protocol. In this study, we enrolled 20 patients for mandible contour surgery. Our protocol is to perform VSP based on 3-D computed tomography data. Then, design and 3-D print surgical templates based on preoperative VSP. The accuracy of the method was analyzed by 3-D comparison of VSP and postoperative results using detailed computer analysis. All patients had symmetric, natural osteotomy lines and satisfactory facial ratios in a single-stage operation. The average relative error of VSP and postoperative result on the entire skull was 0.41 ± 0.13 mm. The average new left gonial error was 0.43 ± 0.77 mm. The average new right gonial error was 0.45 ± 0.69 mm. The average pognion error was 0.79 ± 1.21 mm. Patients were very satisfied with the aesthetic results. Surgeons were very satisfied with the performance of surgical templates to facilitate the operation. Our standardized protocol of VSP and 3-D printed surgical templates-assisted single-stage mandible contour surgery results in accurate, safe, and predictable outcome in a single stage.
Günther, P; Tröger, J; Holland-Cunz, S; Waag, K L; Schenk, J P
2006-08-01
Exact surgical planning is necessary for complex operations of pathological changes in anatomical structures of the pediatric abdomen. 3D visualization and computer-assisted operational planning based on CT data are being increasingly used for difficult operations in adults. To minimize radiation exposure and for better soft tissue contrast, sonography and MRI are the preferred diagnostic methods in pediatric patients. Because of manifold difficulties 3D visualization of these MRI data has not been realized so far, even though the field of embryonal malformations and tumors could benefit from this.A newly developed and modified raycasting-based powerful 3D volume rendering software (VG Studio Max 1.2) for the planning of pediatric abdominal surgery is presented. With the help of specifically developed algorithms, a useful surgical planning system is demonstrated. Thanks to the easy handling and high-quality visualization with enormous gain of information, the presented system is now an established part of routine surgical planning.
Indoor Navigation from Point Clouds: 3d Modelling and Obstacle Detection
NASA Astrophysics Data System (ADS)
Díaz-Vilariño, L.; Boguslawski, P.; Khoshelham, K.; Lorenzo, H.; Mahdjoubi, L.
2016-06-01
In the recent years, indoor modelling and navigation has become a research of interest because many stakeholders require navigation assistance in various application scenarios. The navigational assistance for blind or wheelchair people, building crisis management such as fire protection, augmented reality for gaming, tourism or training emergency assistance units are just some of the direct applications of indoor modelling and navigation. Navigational information is traditionally extracted from 2D drawings or layouts. Real state of indoors, including opening position and geometry for both windows and doors, and the presence of obstacles is commonly ignored. In this work, a real indoor-path planning methodology based on 3D point clouds is developed. The value and originality of the approach consist on considering point clouds not only for reconstructing semantically-rich 3D indoor models, but also for detecting potential obstacles in the route planning and using these for readapting the routes according to the real state of the indoor depictured by the laser scanner.
3D printing of functional biomaterials for tissue engineering.
Zhu, Wei; Ma, Xuanyi; Gou, Maling; Mei, Deqing; Zhang, Kang; Chen, Shaochen
2016-08-01
3D printing is emerging as a powerful tool for tissue engineering by enabling 3D cell culture within complex 3D biomimetic architectures. This review discusses the prevailing 3D printing techniques and their most recent applications in building tissue constructs. The work associated with relatively well-known inkjet and extrusion-based bioprinting is presented with the latest advances in the fields. Emphasis is put on introducing two relatively new light-assisted bioprinting techniques, including digital light processing (DLP)-based bioprinting and laser based two photon polymerization (TPP) bioprinting. 3D bioprinting of vasculature network is particularly discussed for its foremost significance in maintaining tissue viability and promoting functional maturation. Limitations to current bioprinting approaches, as well as future directions of bioprinting functional tissues are also discussed. Copyright © 2016 Elsevier Ltd. All rights reserved.
3D Visualization as a Communicative Aid in Pharmaceutical Advice-Giving over Distance
Dahlbäck, Nils; Petersson, Göran Ingemar
2011-01-01
Background Medication misuse results in considerable problems for both patient and society. It is a complex problem with many contributing factors, including timely access to product information. Objective To investigate the value of 3-dimensional (3D) visualization paired with video conferencing as a tool for pharmaceutical advice over distance in terms of accessibility and ease of use for the advice seeker. Methods We created a Web-based communication service called AssistancePlus that allows an advisor to demonstrate the physical handling of a complex pharmaceutical product to an advice seeker with the aid of 3D visualization and audio/video conferencing. AssistancePlus was tested in 2 separate user studies performed in a usability lab, under realistic settings and emulating a real usage situation. In the first study, 10 pharmacy students were assisted by 2 advisors from the Swedish National Co-operation of Pharmacies’ call centre on the use of an asthma inhaler. The student-advisor interview sessions were filmed on video to qualitatively explore their experience of giving and receiving advice with the aid of 3D visualization. In the second study, 3 advisors from the same call centre instructed 23 participants recruited from the general public on the use of 2 products: (1) an insulin injection pen, and (2) a growth hormone injection syringe. First, participants received advice on one product in an audio-recorded telephone call and for the other product in a video-recorded AssistancePlus session (product order balanced). In conjunction with the AssistancePlus session, participants answered a questionnaire regarding accessibility, perceived expressiveness, and general usefulness of 3D visualization for advice-giving over distance compared with the telephone and were given a short interview focusing on their experience of the 3D features. Results In both studies, participants found the AssistancePlus service helpful in providing clear and exact instructions. In the second study, directly comparing AssistancePlus and the telephone, AssistancePlus was judged positively for ease of communication (P = .001), personal contact (P = .001), explanatory power (P < .001), and efficiency (P < .001). Participants in both studies said that they would welcome this type of service as an alternative to the telephone and to face-to-face interaction when a physical meeting is not possible or not convenient. However, although AssistancePlus was considered as easy to use as the telephone, they would choose AssistancePlus over the telephone only when the complexity of the question demanded the higher level of expressiveness it offers. For simpler questions, a simpler service was preferred. Conclusions 3D visualization paired with video conferencing can be useful for advice-giving over distance, specifically for issues that require a higher level of communicative expressiveness than the telephone can offer. 3D-supported advice-giving can increase the range of issues that can be handled over distance and thus improve access to product information. PMID:21771714
Stereoscopic Vascular Models of the Head and Neck: A Computed Tomography Angiography Visualization
ERIC Educational Resources Information Center
Cui, Dongmei; Lynch, James C.; Smith, Andrew D.; Wilson, Timothy D.; Lehman, Michael N.
2016-01-01
Computer-assisted 3D models are used in some medical and allied health science schools; however, they are often limited to online use and 2D flat screen-based imaging. Few schools take advantage of 3D stereoscopic learning tools in anatomy education and clinically relevant anatomical variations when teaching anatomy. A new approach to teaching…
Kobayashi, Hiroshi; Akiyama, Toru; Okuma, Tomotake; Shinoda, Yusuke; Oka, Hiroyuki; Ito, Nobuaki; Fukumoto, Seiji; Tanaka, Sakae; Kawano, Hirotaka
2017-12-01
Tumor-induced osteomalacia (TIO) is a rare paraneoplastic syndrome usually caused by phosphaturic mesenchymal tumors. Segmental resection has been recommended for these tumors in the bones because curettage was found to be associated with a high local recurrence rate. Navigation-assisted surgery provides radiological information to guide the surgeon during surgery. No previous study has reported on the efficacy of navigation-assisted surgery for tumors in patients with TIO. Therefore, the present study aimed to evaluate the efficacy of navigation-assisted surgery for tumors in patients with TIO. The study included seven patients with TIO who were treated between January 2003 and December 2014 at our hospital. All patients underwent surgical treatment with or without the use of a 3-dimensional (3D) fluoroscopy-based navigation system. The laboratory data and oncological outcomes were evaluated. The follow-up period was 8-128 months. The tumors were located at the femur (n = 4), ischium, spine and ilium (n = 1). Of the seven patients, five underwent navigation-assisted surgery and two underwent surgery without navigation assistance. In the two patients who underwent surgery without navigation assistance, a complete cure was not obtained and osteomalacia did not resolve. One of these two patients and the other five patients who underwent navigation-assisted surgery, one patient had incomplete resection due to massive invasion of the tumor into the spinal canal, but five patients achieved complete excision and recovered from osteomalacia. Navigation-assisted surgery using a 3D fluoroscopy-based navigation system is effective for tumors in patients with TIO.
A Markerless 3D Computerized Motion Capture System Incorporating a Skeleton Model for Monkeys.
Nakamura, Tomoya; Matsumoto, Jumpei; Nishimaru, Hiroshi; Bretas, Rafael Vieira; Takamura, Yusaku; Hori, Etsuro; Ono, Taketoshi; Nishijo, Hisao
2016-01-01
In this study, we propose a novel markerless motion capture system (MCS) for monkeys, in which 3D surface images of monkeys were reconstructed by integrating data from four depth cameras, and a skeleton model of the monkey was fitted onto 3D images of monkeys in each frame of the video. To validate the MCS, first, estimated 3D positions of body parts were compared between the 3D MCS-assisted estimation and manual estimation based on visual inspection when a monkey performed a shuttling behavior in which it had to avoid obstacles in various positions. The mean estimation error of the positions of body parts (3-14 cm) and of head rotation (35-43°) between the 3D MCS-assisted and manual estimation were comparable to the errors between two different experimenters performing manual estimation. Furthermore, the MCS could identify specific monkey actions, and there was no false positive nor false negative detection of actions compared with those in manual estimation. Second, to check the reproducibility of MCS-assisted estimation, the same analyses of the above experiments were repeated by a different user. The estimation errors of positions of most body parts between the two experimenters were significantly smaller in the MCS-assisted estimation than in the manual estimation. Third, effects of methamphetamine (MAP) administration on the spontaneous behaviors of four monkeys were analyzed using the MCS. MAP significantly increased head movements, tended to decrease locomotion speed, and had no significant effect on total path length. The results were comparable to previous human clinical data. Furthermore, estimated data following MAP injection (total path length, walking speed, and speed of head rotation) correlated significantly between the two experimenters in the MCS-assisted estimation (r = 0.863 to 0.999). The results suggest that the presented MCS in monkeys is useful in investigating neural mechanisms underlying various psychiatric disorders and developing pharmacological interventions.
Synchronous exfoliation and assembly of graphene on 3D Ni(OH)2 for supercapacitors.
Ma, Liguo; Zheng, Maojun; Liu, Shaohua; Li, Qiang; You, Yuxiu; Wang, Faze; Ma, Li; Shen, Wenzhong
2016-11-08
Nowadays, new approaches to fabricate high-performance electrode materials are of vital importance in the renewable energy field. Here, we present a facile synthesis procedure of 3D Ni(OH) 2 /graphene hybrids for supercapacitors via synchronous electrochemical-assisted exfoliation and assembly of graphene on 3D Ni(OH) 2 networks. With the assistance of an electric field, the electrochemically exfoliated high-quality graphene can be readily, uniformly assembled on the surfaces of 3D Ni(OH) 2 . When serving as electrode materials for supercapacitors, the resulting 3D Ni(OH) 2 /graphene composites exhibited excellent specific capacitance (263 mF cm -2 at 2 mA cm -2 ), remarkable rate capability and super-long cycle life (retention of 94.1% even after 10 000 continuous charge-discharge cycles), which may be attributed to their highly porous, stable 3D architecture as well as uniform, firm anchoring of ultrathin graphene on their surfaces. Therefore, our approach provides a facile strategy for the large-scale synthesis of high-quality graphene based composites towards various applications.
Improving Assistive Technology Service by Using 3D Printing: Three Case Studies.
Watanabe, Takashi; Hatakeyama, Takuro; Tomiita, Mitsuru
2015-01-01
Assistive technology services are essential for adapting assistive devices to the individual needs of users with disabilities. In this study, we attempted to apply three-dimensional (3D) printing technology to three actual cases, and to study its use, effectiveness, and future applications. We assessed the usefulness of 3D printing technology by categorizing its utilization after reviewing the outcomes of these case studies. In future work, we aim to gather additional case studies and derive information on using 3D printing technology that will enable its effective application in the process of assistive technology services.
Design & control of a 3D stroke rehabilitation platform.
Cai, Z; Tong, D; Meadmore, K L; Freeman, C T; Hughes, A M; Rogers, E; Burridge, J H
2011-01-01
An upper limb stroke rehabilitation system is developed which combines electrical stimulation with mechanical arm support, to assist patients performing 3D reaching tasks in a virtual reality environment. The Stimulation Assistance through Iterative Learning (SAIL) platform applies electrical stimulation to two muscles in the arm using model-based control schemes which learn from previous trials of the task. This results in accurate movement which maximises the therapeutic effect of treatment. The principal components of the system are described and experimental results confirm its efficacy for clinical use in upper limb stroke rehabilitation. © 2011 IEEE
NASA Astrophysics Data System (ADS)
Fukuzawa, M.; Kawata, K.; Nakamori, N.; Kitsunezuka, Y.
2011-03-01
By real-time visual feedback of 3D scatter diagram of pulsatile tissue-motion, freehand ultrasonic diagnosis of neonatal ischemic diseases has been assisted at the bedside. The 2D ultrasonic movie was taken with a conventional ultrasonic apparatus (ATL HDI5000) and ultrasonic probes of 5-7 MHz with the compact tilt-sensor to measure the probe orientation. The real-time 3D visualization was realized by developing an extended version of the PC-based visualization system. The software was originally developed on the DirectX platform and optimized with the streaming SIMD extensions. The 3D scatter diagram of the latest pulsatile tissues has been continuously generated and visualized as projection image with the ultrasonic movie in the current section more than 15 fps. It revealed the 3D structure of pulsatile tissues such as middle and posterior cerebral arteries, Willis ring and cerebellar arteries, in which pediatricians have great interests in the blood flow because asphyxiated and/or low-birth-weight neonates have a high risk of ischemic diseases such as hypoxic-ischemic encephalopathy and periventricular leukomalacia. Since the pulsatile tissue-motion is due to local blood flow, it can be concluded that the system developed in this work is very useful to assist freehand ultrasonic diagnosis of ischemic diseases in the neonatal cranium.
Proteopedia: 3D Visualization and Annotation of Transcription Factor-DNA Readout Modes
ERIC Educational Resources Information Center
Dantas Machado, Ana Carolina; Saleebyan, Skyler B.; Holmes, Bailey T.; Karelina, Maria; Tam, Julia; Kim, Sharon Y.; Kim, Keziah H.; Dror, Iris; Hodis, Eran; Martz, Eric; Compeau, Patricia A.; Rohs, Remo
2012-01-01
3D visualization assists in identifying diverse mechanisms of protein-DNA recognition that can be observed for transcription factors and other DNA binding proteins. We used Proteopedia to illustrate transcription factor-DNA readout modes with a focus on DNA shape, which can be a function of either nucleotide sequence (Hox proteins) or base pairing…
Rodriguez-Florez, Naiara; Bruse, Jan L; Borghi, Alessandro; Vercruysse, Herman; Ong, Juling; James, Greg; Pennec, Xavier; Dunaway, David J; Jeelani, N U Owase; Schievano, Silvia
2017-10-01
Spring-assisted cranioplasty is performed to correct the long and narrow head shape of children with sagittal synostosis. Such corrective surgery involves osteotomies and the placement of spring-like distractors, which gradually expand to widen the skull until removal about 4 months later. Due to its dynamic nature, associations between surgical parameters and post-operative 3D head shape features are difficult to comprehend. The current study aimed at applying population-based statistical shape modelling to gain insight into how the choice of surgical parameters such as craniotomy size and spring positioning affects post-surgical head shape. Twenty consecutive patients with sagittal synostosis who underwent spring-assisted cranioplasty at Great Ormond Street Hospital for Children (London, UK) were prospectively recruited. Using a nonparametric statistical modelling technique based on mathematical currents, a 3D head shape template was computed from surface head scans of sagittal patients after spring removal. Partial least squares (PLS) regression was employed to quantify and visualise trends of localised head shape changes associated with the surgical parameters recorded during spring insertion: anterior-posterior and lateral craniotomy dimensions, anterior spring position and distance between anterior and posterior springs. Bivariate correlations between surgical parameters and corresponding PLS shape vectors demonstrated that anterior-posterior (Pearson's [Formula: see text]) and lateral craniotomy dimensions (Spearman's [Formula: see text]), as well as the position of the anterior spring ([Formula: see text]) and the distance between both springs ([Formula: see text]) on average had significant effects on head shapes at the time of spring removal. Such effects were visualised on 3D models. Population-based analysis of 3D post-operative medical images via computational statistical modelling tools allowed for detection of novel associations between surgical parameters and head shape features achieved following spring-assisted cranioplasty. The techniques described here could be extended to other cranio-maxillofacial procedures in order to assess post-operative outcomes and ultimately facilitate surgical decision making.
Currie, Maria E; Trejos, Ana Luisa; Rayman, Reiza; Chu, Michael W A; Patel, Rajni; Peters, Terry; Kiaii, Bob B
2013-01-01
The purpose of this study was to determine the effect of three-dimensional (3D) binocular, stereoscopic, and two-dimensional (2D) monocular visualization on robotics-assisted mitral valve annuloplasty versus conventional techniques in an ex vivo animal model. In addition, we sought to determine whether these effects were consistent between novices and experts in robotics-assisted cardiac surgery. A cardiac surgery test-bed was constructed to measure forces applied during mitral valve annuloplasty. Sutures were passed through the porcine mitral valve annulus by the participants with different levels of experience in robotics-assisted surgery and tied in place using both robotics-assisted and conventional surgery techniques. The mean time for both the experts and the novices using 3D visualization was significantly less than that required using 2D vision (P < 0.001). However, there was no significant difference in the maximum force applied by the novices to the mitral valve during suturing (P = 0.7) and suture tying (P = 0.6) using either 2D or 3D visualization. The mean time required and forces applied by both the experts and the novices were significantly less using the conventional surgical technique than when using the robotic system with either 2D or 3D vision (P < 0.001). Despite high-quality binocular images, both the experts and the novices applied significantly more force to the cardiac tissue during 3D robotics-assisted mitral valve annuloplasty than during conventional open mitral valve annuloplasty. This finding suggests that 3D visualization does not fully compensate for the absence of haptic feedback in robotics-assisted cardiac surgery.
Effective 2D-3D medical image registration using Support Vector Machine.
Qi, Wenyuan; Gu, Lixu; Zhao, Qiang
2008-01-01
Registration of pre-operative 3D volume dataset and intra-operative 2D images gradually becomes an important technique to assist radiologists in diagnosing complicated diseases easily and quickly. In this paper, we proposed a novel 2D/3D registration framework based on Support Vector Machine (SVM) to compensate the disadvantages of generating large number of DRR images in the stage of intra-operation. Estimated similarity metric distribution could be built up from the relationship between parameters of transform and prior sparse target metric values by means of SVR method. Based on which, global optimal parameters of transform are finally searched out by an optimizer in order to guide 3D volume dataset to match intra-operative 2D image. Experiments reveal that our proposed registration method improved performance compared to conventional registration method and also provided a precise registration result efficiently.
Rose, Jessica; Cahill-Rowley, Katelyn; Butler, Erin E
2017-11-01
Cerebral palsy (CP) is the most common childhood motor disability and often results in debilitating walking abnormalities, such as flexed-knee and stiff-knee gait. Current medical and surgical treatments are only partially effective in improving gait abnormalities and may cause significant muscle weakness. However, emerging artificial walking technologies, such as step-initiated, multichannel neuromuscular electrical stimulation (NMES), can substantially improve gait patterns and promote muscle strength in children with spastic CP. NMES may also be applied to specific lumbar-sacral sensory roots to reduce spasticity. Development of tablet computer-based multichannel NMES can leverage lightweight, wearable wireless stimulators, advanced control design, and surface electrodes to activate lower-limb muscles. Musculoskeletal models have been used to characterize muscle contributions to unimpaired gait and identify high muscle demands, which can help guide multichannel NMES-assisted gait protocols. In addition, patient-specific NMES-assisted gait protocols based on 3D gait analysis can facilitate the appropriate activation of lower-limb muscles to achieve a more functional gait: stance-phase hip and knee extension and swing-phase sequence of hip and knee flexion followed by rapid knee extension. NMES-assisted gait treatment can be conducted as either clinic-based or home-based programs. Rigorous testing of multichannel NMES-assisted gait training protocols will determine optimal treatment dosage for future clinical trials. Evidence-based outcome evaluation using 3D kinematics or temporal-spatial gait parameters will help determine immediate neuroprosthetic effects and longer term neurotherapeutic effects of step-initiated, multichannel NMES-assisted gait in children with spastic CP. Multichannel NMES is a promising assistive technology to help children with spastic CP achieve a more upright, functional gait. © 2017 International Center for Artificial Organs and Transplantation and Wiley Periodicals, Inc.
Ionic liquid-assisted hydrothermal synthesis of dendrite-like NaY(MoO4)2:Tb3+ phosphor
NASA Astrophysics Data System (ADS)
Tian, Yue; Chen, Baojiu; Tian, Bining; Sun, Jiashi; Li, Xiangping; Zhang, Jinsu; Cheng, Lihong; Zhong, Haiyang; Zhong, Hua; Meng, Qingyu; Hua, Ruinian
2012-07-01
Micro-sized NaY(MoO4)2:Tb3+ phosphors with dendritic morphology was synthesized by a ionic liquid-assisted hydrothermal process. X-ray diffraction (XRD) indicated that the as-prepared product is pure tetragonal phase of NaY(MoO4)2. Field emission scanning electron microscopy (FE-SEM) images showed that the as-prepared NaY(MoO4)2:Tb3+ phosphors have dendritic morphology. The photoluminescent (PL) spectra displayed that the as-prepared NaY(MoO4)2:Tb3+ phosphors show a stronger green emission with main emission wavelength 545 nm corresponding to the 5D4→7F5 transition of Tb3+ ion, and the optimal Tb3+ doping concentration for obtaining maximum emission intensity was confirmed to be 10 mol%. Based on Van Uitert's and Dexter's models the electric dipole-dipole (D-D) interaction was confirmed to be responsible for the concentration quenching of 5D4 fluorescence of Tb3+ in the NaY(MoO4)2:Tb3+ phosphors. The intrinsic radiative transition lifetime of 5D4 level is found to be 0.703 ms.
Optical and Photothermal Behaviors of Colloidal and Self-Assembled Magnetic-Plasmonic Nanostructures
NASA Astrophysics Data System (ADS)
Liu, Kai
This dissertation is based on numerous efforts in exploring the capabilties of numerical simulation for investigating novel optical phenomena in different colloidal plasmonic systems. The dissertation includes five chapters. Chapter 1 contains a general introduction to the fundamentals of plasmonic behaviors in colloidal clusters and bottom-up self-assembly methods for manufacturing colloidal clusters which include magnetic based and DNA-assisted pathways. Chapter 2 presents a systematic comparison of optical and thermodynamic properties of near-infrared colloidal nanoparticles, including SiO2 Au core-shell, Au nanocage and Au nanorod, and an example of the nanobubble-based photothermal therapy application. In Chapter 3, a optical phenomenon named Fano resonance is demonstrated in a colloidal heptamer design which consists of seven Fe 3O4 Au core-shell nanoparticles. The incorporation of the magnetic core enables a magnetic-assisted self-assembly process which will be discussed after the photonic analysis. In Chapter 4, the optical behaviors in a 1D magnetic-plasmonic chain are explored. A demonstration of the magnetic-based self-assembly of this 1D chain is given. Chapter 5 is focused on the study of the chiral optical responses in a helical nanoscale system which follows a 3D helical arrangement of Fe3O4 Au core-shell nanoparticles.
[Constructing 3-dimensional colorized digital dental model assisted by digital photography].
Ye, Hong-qiang; Liu, Yu-shu; Liu, Yun-song; Ning, Jing; Zhao, Yi-jiao; Zhou, Yong-sheng
2016-02-18
To explore a method of constructing universal 3-dimensional (3D) colorized digital dental model which can be displayed and edited in common 3D software (such as Geomagic series), in order to improve the visual effect of digital dental model in 3D software. The morphological data of teeth and gingivae were obtained by intra-oral scanning system (3Shape TRIOS), constructing 3D digital dental models. The 3D digital dental models were exported as STL files. Meanwhile, referring to the accredited photography guide of American Academy of Cosmetic Dentistry (AACD), five selected digital photographs of patients'teeth and gingivae were taken by digital single lens reflex camera (DSLR) with the same exposure parameters (except occlusal views) to capture the color data. In Geomagic Studio 2013, after STL file of 3D digital dental model being imported, digital photographs were projected on 3D digital dental model with corresponding position and angle. The junctions of different photos were carefully trimmed to get continuous and natural color transitions. Then the 3D colorized digital dental model was constructed, which was exported as OBJ file or WRP file which was a special file for software of Geomagic series. For the purpose of evaluating the visual effect of the 3D colorized digital model, a rating scale on color simulation effect in views of patients'evaluation was used. Sixteen patients were recruited and their scores on colored and non-colored digital dental models were recorded. The data were analyzed using McNemar-Bowker test in SPSS 20. Universal 3D colorized digital dental model with better color simulation was constructed based on intra-oral scanning and digital photography. For clinical application, the 3D colorized digital dental models, combined with 3D face images, were introduced into 3D smile design of aesthetic rehabilitation, which could improve the patients' cognition for the esthetic digital design and virtual prosthetic effect. Universal 3D colorized digital dental model with better color simulation can be constructed assisted by 3D dental scanning system and digital photography. In clinical practice, the communication between dentist and patients could be improved assisted by the better visual perception since the colorized 3D digital dental models with better color simulation effect.
Semi-autonomous wheelchair system using stereoscopic cameras.
Nguyen, Jordan S; Nguyen, Thanh H; Nguyen, Hung T
2009-01-01
This paper is concerned with the design and development of a semi-autonomous wheelchair system using stereoscopic cameras to assist hands-free control technologies for severely disabled people. The stereoscopic cameras capture an image from both the left and right cameras, which are then processed with a Sum of Absolute Differences (SAD) correlation algorithm to establish correspondence between image features in the different views of the scene. This is used to produce a stereo disparity image containing information about the depth of objects away from the camera in the image. A geometric projection algorithm is then used to generate a 3-Dimensional (3D) point map, placing pixels of the disparity image in 3D space. This is then converted to a 2-Dimensional (2D) depth map allowing objects in the scene to be viewed and a safe travel path for the wheelchair to be planned and followed based on the user's commands. This assistive technology utilising stereoscopic cameras has the purpose of automated obstacle detection, path planning and following, and collision avoidance during navigation. Experimental results obtained in an indoor environment displayed the effectiveness of this assistive technology.
The role of three-dimensional visualization in robotics-assisted cardiac surgery
NASA Astrophysics Data System (ADS)
Currie, Maria; Trejos, Ana Luisa; Rayman, Reiza; Chu, Michael W. A.; Patel, Rajni; Peters, Terry; Kiaii, Bob
2012-02-01
Objectives: The purpose of this study was to determine the effect of three-dimensional (3D) versus two-dimensional (2D) visualization on the amount of force applied to mitral valve tissue during robotics-assisted mitral valve annuloplasty, and the time to perform the procedure in an ex vivo animal model. In addition, we examined whether these effects are consistent between novices and experts in robotics-assisted cardiac surgery. Methods: A cardiac surgery test-bed was constructed to measure forces applied by the da Vinci surgical system (Intuitive Surgical, Sunnyvale, CA) during mitral valve annuloplasty. Both experts and novices completed roboticsassisted mitral valve annuloplasty with 2D and 3D visualization. Results: The mean time for both experts and novices to suture the mitral valve annulus and to tie sutures using 3D visualization was significantly less than that required to suture the mitral valve annulus and to tie sutures using 2D vision (p∠0.01). However, there was no significant difference in the maximum force applied by novices to the mitral valve during suturing (p = 0.3) and suture tying (p = 0.6) using either 2D or 3D visualization. Conclusion: This finding suggests that 3D visualization does not fully compensate for the absence of haptic feedback in robotics-assisted cardiac surgery. Keywords: Robotics-assisted surgery, visualization, cardiac surgery
3D-Structured Stretchable Strain Sensors for Out-of-Plane Force Detection.
Liu, Zhiyuan; Qi, Dianpeng; Leow, Wan Ru; Yu, Jiancan; Xiloyannnis, Michele; Cappello, Leonardo; Liu, Yaqing; Zhu, Bowen; Jiang, Ying; Chen, Geng; Masia, Lorenzo; Liedberg, Bo; Chen, Xiaodong
2018-05-17
Stretchable strain sensors, as the soft mechanical interface, provide the key mechanical information of the systems for healthcare monitoring, rehabilitation assistance, soft exoskeletal devices, and soft robotics. Stretchable strain sensors based on 2D flat film have been widely developed to monitor the in-plane force applied within the plane where the sensor is placed. However, to comprehensively obtain the mechanical feedback, the capability to detect the out-of-plane force, caused by the interaction outside of the plane where the senor is located, is needed. Herein, a 3D-structured stretchable strain sensor is reported to monitor the out-of-plane force by employing 3D printing in conjunction with out-of-plane capillary force-assisted self-pinning of carbon nanotubes. The 3D-structured sensor possesses large stretchability, multistrain detection, and strain-direction recognition by one single sensor. It is demonstrated that out-of-plane forces induced by the air/fluid flow are reliably monitored and intricate flow details are clearly recorded. The development opens up for the exploration of next-generation 3D stretchable sensors for electronic skin and soft robotics. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Rabattu, Pierre-Yves; Massé, Benoit; Ulliana, Federico; Rousset, Marie-Christine; Rohmer, Damien; Léon, Jean-Claude; Palombi, Olivier
2015-01-01
Embryology is a complex morphologic discipline involving a set of entangled mechanisms, sometime difficult to understand and to visualize. Recent computer based techniques ranging from geometrical to physically based modeling are used to assist the visualization and the simulation of virtual humans for numerous domains such as surgical simulation and learning. On the other side, the ontology-based approach applied to knowledge representation is more and more successfully adopted in the life-science domains to formalize biological entities and phenomena, thanks to a declarative approach for expressing and reasoning over symbolic information. 3D models and ontologies are two complementary ways to describe biological entities that remain largely separated. Indeed, while many ontologies providing a unified formalization of anatomy and embryology exist, they remain only descriptive and make the access to anatomical content of complex 3D embryology models and simulations difficult. In this work, we present a novel ontology describing the development of the human embryology deforming 3D models. Beyond describing how organs and structures are composed, our ontology integrates a procedural description of their 3D representations, temporal deformation and relations with respect to their developments. We also created inferences rules to express complex connections between entities. It results in a unified description of both the knowledge of the organs deformation and their 3D representations enabling to visualize dynamically the embryo deformation during the Carnegie stages. Through a simplified ontology, containing representative entities which are linked to spatial position and temporal process information, we illustrate the added-value of such a declarative approach for interactive simulation and visualization of 3D embryos. Combining ontologies and 3D models enables a declarative description of different embryological models that capture the complexity of human developmental anatomy. Visualizing embryos with 3D geometric models and their animated deformations perhaps paves the way towards some kind of hypothesis-driven application. These can also be used to assist the learning process of this complex knowledge. http://www.mycorporisfabrica.org/.
75 FR 15693 - Extension of Web-Based TRICARE Assistance Program Demonstration Project
Federal Register 2010, 2011, 2012, 2013, 2014
2010-03-30
... DEPARTMENT OF DEFENSE Office of the Secretary Extension of Web-Based TRICARE Assistance Program Demonstration Project AGENCY: Department of Defense (DoD). ACTION: Notice of a Web-Based TRICARE Assistance... States Code, Section 1092, entitled Web-Based TRICARE Assistance Program. This demonstration was...
NASA Astrophysics Data System (ADS)
Xie, Nanjie; Zhang, Hao; Liu, Bo; Wu, Jixuan; Song, Binbin; Han, Tingting
2017-11-01
A highly sensitive microfluidic sensor based on a microfiber-assisted Mach-Zehnder interferometer (MAMZI) is proposed and experimentally demonstrated for the detection of low-concentration glucose solution. A segment of microfiber tapered from standard single-mode fiber (SMF) is spliced between two SMFs with pre-designed lateral offset to constitute the miniaturized MAMZI probe. The transmission spectral response to environmental refractive index variation has been experimentally investigated for glucose concentration ranges of 300 mg dL-1 to 3000 mg dL-1 and 0 to 270 mg dL-1 and the glucose concentration detection limit is 3 mg dL-1, and the experimentally observed transmission spectral responses are in accordance with our theoretical simulation results. Owing to its high sensitivity, non-enzymatic operation method, ease of fabrication and compact size, our proposed MAMZI for glucose sensing is anticipated to be employed in biomedical applications.
[Application of computer-assisted 3D imaging simulation for surgery].
Matsushita, S; Suzuki, N
1994-03-01
This article describes trends in application of various imaging technology in surgical planning, navigation, and computer aided surgery. Imaging information is essential factor for simulation in medicine. It includes three dimensional (3D) image reconstruction, neuro-surgical navigation, creating substantial model based on 3D imaging data and etc. These developments depend mostly on 3D imaging technique, which is much contributed by recent computer technology. 3D imaging can offer new intuitive information to physician and surgeon, and this method is suitable for mechanical control. By utilizing simulated results, we can obtain more precise surgical orientation, estimation, and operation. For more advancement, automatic and high speed recognition of medical imaging is being developed.
A GIS Based 3D Online Decision Assistance System for Underground Energy Storage in Northern Germany
NASA Astrophysics Data System (ADS)
Nolde, M.; Schwanebeck, M.; Biniyaz, E.; Duttmann, R.
2014-12-01
We would like to present a GIS-based 3D online decision assistance system for underground energy storage. Its aim is to support the local land use planning authorities through pre-selection of possible sites for thermal, electrical and substantial underground energy storages. Since the extension of renewable energies has become legal requirement in Germany, the underground storing of superfluously produced green energy (such as during a heavy wind event) in the form of compressed air, gas or heated water has become increasingly important. However, the selection of suitable sites is a complex task. The assistance system uses data of geological features such as rock layers, salt caverns and faults enriched with attribute data such as rock porosity and permeability. This information is combined with surface data of the existing energy infrastructure, such as locations of wind and biogas stations, power line arrangement and cable capacity, and energy distribution stations. Furthermore, legal obligations such as protected areas on the surface and current underground mining permissions are used for the decision finding process. Not only the current situation but also prospective scenarios, such as expected growth in produced amount of energy are incorporated in the system. The decision process is carried out via the 'Analytic Hierarchy Process' (AHP) methodology of the 'Multi Object Decision Making' (MODM) approach. While the process itself is completely automated, the user has full control of the weighting of the different factors via the web interface. The system is implemented as an online 3D server GIS environment, with no software needed to be installed on the user side. The results are visualized as interactive 3d graphics. The implementation of the assistance system is based exclusively on free and open source software, and utilizes the 'Python' programming language in combination with current web technologies, such as 'HTML5', 'CSS3' and 'JavaScript'. It is developed at Kiel University for the federal state of Schleswig-Holstein in northern Germany. This work is part of project 'ANGUS+', lead by Prof. Dr. Sebastian Bauer and funded by the German Ministry for Education and Research (BMBF).
Atlas-based system for functional neurosurgery
NASA Astrophysics Data System (ADS)
Nowinski, Wieslaw L.; Yeo, Tseng T.; Yang, Guo L.; Dow, Douglas E.
1997-05-01
This paper addresses the development of an atlas-based system for preoperative functional neurosurgery planning and training, intraoperative support and postoperative analysis. The system is based on Atlas of Stereotaxy of the Human Brain by Schaltenbrand and Wahren used for interactive segmentation and labeling of clinical data in 2D/3D, and for assisting stereotactic targeting. The atlas microseries are digitized, enhanced, segmented, labeled, aligned and organized into mutually preregistered atlas volumes 3D models of the structures are also constructed. The atlas may be interactively registered with the actual patient's data. Several other features are also provided including data reformatting, visualization, navigation, mensuration, and stereotactic path display and editing in 2D/3D. The system increases the accuracy of target definition, reduces the time of planning and time of the procedure itself. It also constitutes a research platform for the construction of more advanced neurosurgery supporting tools and brain atlases.
NASA Astrophysics Data System (ADS)
Hu, Lijiao; Ju, Yang; Hosoi, Atsushi
2014-03-01
Cu2O grass-like and ZnO flower-like nanoarchitectures were fabricated directly on Cu powders and Zn powders using a novel thermal oxidation stress-induced (TOS) method based on catalyst assistance at a low temperature of 150°C under moderate humid atmosphere. The experiments of Al powder were also carried out based on TOS method. Overlapping migration (OLM) of Cu and Zn atoms and toothpaste squeezing migration (TSM) of Al atoms caused by different atom densities in metal oxide materials were studied.
Intelligent web agents for a 3D virtual community
NASA Astrophysics Data System (ADS)
Dave, T. M.; Zhang, Yanqing; Owen, G. S. S.; Sunderraman, Rajshekhar
2003-08-01
In this paper, we propose an Avatar-based intelligent agent technique for 3D Web based Virtual Communities based on distributed artificial intelligence, intelligent agent techniques, and databases and knowledge bases in a digital library. One of the goals of this joint NSF (IIS-9980130) and ACM SIGGRAPH Education Committee (ASEC) project is to create a virtual community of educators and students who have a common interest in comptuer graphics, visualization, and interactive techniqeus. In this virtual community (ASEC World) Avatars will represent the educators, students, and other visitors to the world. Intelligent agents represented as specially dressed Avatars will be available to assist the visitors to ASEC World. The basic Web client-server architecture of the intelligent knowledge-based avatars is given. Importantly, the intelligent Web agent software system for the 3D virtual community is implemented successfully.
NASA Astrophysics Data System (ADS)
Rajabzadeh-Oghaz, Hamidreza; Varble, Nicole; Davies, Jason M.; Mowla, Ashkan; Shakir, Hakeem J.; Sonig, Ashish; Shallwani, Hussain; Snyder, Kenneth V.; Levy, Elad I.; Siddiqui, Adnan H.; Meng, Hui
2017-03-01
Neurosurgeons currently base most of their treatment decisions for intracranial aneurysms (IAs) on morphological measurements made manually from 2D angiographic images. These measurements tend to be inaccurate because 2D measurements cannot capture the complex geometry of IAs and because manual measurements are variable depending on the clinician's experience and opinion. Incorrect morphological measurements may lead to inappropriate treatment strategies. In order to improve the accuracy and consistency of morphological analysis of IAs, we have developed an image-based computational tool, AView. In this study, we quantified the accuracy of computer-assisted adjuncts of AView for aneurysmal morphologic assessment by performing measurement on spheres of known size and anatomical IA models. AView has an average morphological error of 0.56% in size and 2.1% in volume measurement. We also investigate the clinical utility of this tool on a retrospective clinical dataset and compare size and neck diameter measurement between 2D manual and 3D computer-assisted measurement. The average error was 22% and 30% in the manual measurement of size and aneurysm neck diameter, respectively. Inaccuracies due to manual measurements could therefore lead to wrong treatment decisions in 44% and inappropriate treatment strategies in 33% of the IAs. Furthermore, computer-assisted analysis of IAs improves the consistency in measurement among clinicians by 62% in size and 82% in neck diameter measurement. We conclude that AView dramatically improves accuracy for morphological analysis. These results illustrate the necessity of a computer-assisted approach for the morphological analysis of IAs.
Driver head pose tracking with thermal camera
NASA Astrophysics Data System (ADS)
Bole, S.; Fournier, C.; Lavergne, C.; Druart, G.; Lépine, T.
2016-09-01
Head pose can be seen as a coarse estimation of gaze direction. In automotive industry, knowledge about gaze direction could optimize Human-Machine Interface (HMI) and Advanced Driver Assistance Systems (ADAS). Pose estimation systems are often based on camera when applications have to be contactless. In this paper, we explore uncooled thermal imagery (8-14μm) for its intrinsic night vision capabilities and for its invariance versus lighting variations. Two methods are implemented and compared, both are aided by a 3D model of the head. The 3D model, mapped with thermal texture, allows to synthesize a base of 2D projected models, differently oriented and labeled in yaw and pitch. The first method is based on keypoints. Keypoints of models are matched with those of the query image. These sets of matchings, aided with the 3D shape of the model, allow to estimate 3D pose. The second method is a global appearance approach. Among all 2D models of the base, algorithm searches the one which is the closest to the query image thanks to a weighted least squares difference.
Ahmed, Sameer; VanKoevering, Kyle K; Kline, Stephanie; Green, Glenn E; Arts, H Alexander
2017-10-01
To explore the perioperative utility of three-dimensionally (3D)-printed temporal bone models of patients undergoing repair of lateral skull base defects and spontaneous cerebrospinal fluid leaks with the middle cranial fossa approach. Case series. 3D-printed temporal bone models-based on patient-specific, high-resolution computed tomographic imaging-were constructed using inexpensive polymer materials. Preoperatively, the models demonstrated the extent of temporal lobe retraction necessary to visualize the proposed defects in the lateral skull base. Also preoperatively, Silastic sheeting was arranged across the modeled tegmen, marked, and cut to cover all of the proposed defect sites. The Silastic sheeting was then sterilized and subsequently served as a precise intraoperative template for a synthetic dural replacement graft. Of note, these grafts were customized without needing to retract the temporal lobe. Five patients underwent the middle cranial fossa approach assisted by 3D-printed temporal bone models to repair tegmen defects and spontaneous cerebrospinal fluid leaks. No complications were encountered. The prefabricated dural repair grafts were easily placed and fit precisely onto the middle fossa floor without any additional modifications. All defects were covered as predicted by the 3D temporal bone models. At their postoperative visits, all five patients maintained resolution of their spontaneous cerebrospinal fluid leaks. Inexpensive 3D-printed temporal bone models of tegmen defects can serve as beneficial adjuncts during lateral skull base repair. The models provide a panoramic preoperative view of all tegmen defects and allow for custom templating of dural grafts without temporal lobe retraction. 4 Laryngoscope, 127:2347-2351, 2017. © 2016 The American Laryngological, Rhinological and Otological Society, Inc.
Zhou, Jiayu; Pan, Bo; Yang, Qinghua; Zhao, Yanyong; He, Leren; Lin, Lin; Sun, Hengyun; Song, Yupeng; Yu, Xiaobo; Sun, Zhongyang; Jiang, Haiyue
2016-10-01
During microtia reconstruction, the intraoperative design of the cartilage framework is important for the appearance and symmetry of the bilateral auricles. Templates (traditionally, the X-ray film template) are usually utilized to complete the task, which can provide cues regarding size, cranioauricular angle and positioning to the surgeons. With a combination of three-dimensional (3D) scanning and additive manufacturing (AM) techniques, we utilized two different ear-shaped templates (sheet moulding and 3D templates) during the fabrication of 3D-customized autologous cartilage frameworks for auricle reconstruction. Forty unilateral microtia patients were included in the study. All the patients underwent auricle reconstruction using the tissue-expanding technique assisted by the new AM templates. Images were processed using computer-aided design software and exported to print two different AM ear-shaped templates: sheet moulding and 3D. Both templates were assisted by the 3D framework fabrication. The 3D images of each patient's head were captured preoperatively using a 3D scanner. X-ray film templates were also made for the patients. The lengths and widths of the contralateral auricles, X-ray film and sheet moulding templates were measured in triplicate. The error of the template and the contralateral auricle were used to compare the accuracy between the two templates. Between January and May 2014, 40 unilateral microtia patients aged 6-29 years were included in this study. All patients underwent auricle reconstruction using autogenous costal cartilage. The sterilized AM templates were used to assist in the framework fabrication. The operative time was decreased by an average of 15 min compared with the method assisted by the X-ray film template. Postoperative appearance evaluation (based on five indexes: symmetry, length, width, cranioauricular angle and the substructure of the reconstructed ear) was performed by both the doctors and the patients (or their parents). Follow-up (ranging from 9 to 18 months) showed that all of the patients obtained satisfactory results with life-like 3D configuration and symmetric cranioauricular angle. The follow-up showed that no surgery-related complications occurred. Comparing the accuracy of the X-ray film and sheet moulding templates, the average errors of length were 1.8 mm ± 1.44 mm and 0.39 mm ± 0.35 mm, respectively, and the average width errors were 1.32 mm ± 0.88 mm and 0.3 mm ± 0.47 mm, respectively. The new sheet moulding template was more accurate than the X-ray template. The new sheet-moulding template is much more accurate than the traditional X-ray film template. Framework fabrication assisted by accurate 3D and informative AM templates contributed to individualized cartilage framework fabrication and satisfactory results. Copyright © 2016 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved.
Computer-Vision-Assisted Palm Rehabilitation With Supervised Learning.
Vamsikrishna, K M; Dogra, Debi Prosad; Desarkar, Maunendra Sankar
2016-05-01
Physical rehabilitation supported by the computer-assisted-interface is gaining popularity among health-care fraternity. In this paper, we have proposed a computer-vision-assisted contactless methodology to facilitate palm and finger rehabilitation. Leap motion controller has been interfaced with a computing device to record parameters describing 3-D movements of the palm of a user undergoing rehabilitation. We have proposed an interface using Unity3D development platform. Our interface is capable of analyzing intermediate steps of rehabilitation without the help of an expert, and it can provide online feedback to the user. Isolated gestures are classified using linear discriminant analysis (DA) and support vector machines (SVM). Finally, a set of discrete hidden Markov models (HMM) have been used to classify gesture sequence performed during rehabilitation. Experimental validation using a large number of samples collected from healthy volunteers reveals that DA and SVM perform similarly while applied on isolated gesture recognition. We have compared the results of HMM-based sequence classification with CRF-based techniques. Our results confirm that both HMM and CRF perform quite similarly when tested on gesture sequences. The proposed system can be used for home-based palm or finger rehabilitation in the absence of experts.
Intensity-based 2D 3D registration for lead localization in robot guided deep brain stimulation
NASA Astrophysics Data System (ADS)
Hunsche, Stefan; Sauner, Dieter; El Majdoub, Faycal; Neudorfer, Clemens; Poggenborg, Jörg; Goßmann, Axel; Maarouf, Mohammad
2017-03-01
Intraoperative assessment of lead localization has become a standard procedure during deep brain stimulation surgery in many centers, allowing immediate verification of targeting accuracy and, if necessary, adjustment of the trajectory. The most suitable imaging modality to determine lead positioning, however, remains controversially discussed. Current approaches entail the implementation of computed tomography and magnetic resonance imaging. In the present study, we adopted the technique of intensity-based 2D 3D registration that is commonly employed in stereotactic radiotherapy and spinal surgery. For this purpose, intraoperatively acquired 2D x-ray images were fused with preoperative 3D computed tomography (CT) data to verify lead placement during stereotactic robot assisted surgery. Accuracy of lead localization determined from 2D 3D registration was compared to conventional 3D 3D registration in a subsequent patient study. The mean Euclidian distance of lead coordinates estimated from intensity-based 2D 3D registration versus flat-panel detector CT 3D 3D registration was 0.7 mm ± 0.2 mm. Maximum values of these distances amounted to 1.2 mm. To further investigate 2D 3D registration a simulation study was conducted, challenging two observers to visually assess artificially generated 2D 3D registration errors. 95% of deviation simulations, which were visually assessed as sufficient, had a registration error below 0.7 mm. In conclusion, 2D 3D intensity-based registration revealed high accuracy and reliability during robot guided stereotactic neurosurgery and holds great potential as a low dose, cost effective means for intraoperative lead localization.
DoD Civilian Drug Abuse Testing Program
1988-08-23
employee assistance programs ( EAPs ). DoD Components must obtain approval of the ASD(HA) for specimen collection and laboratory testing... Employee . A DoD employee paid from appropriated funds. 2. Employee Assistance Programs ( EAPs ). DoD Component-based counseling programs that offer...Renumber Ś." to ř." Subparagraph E.5.a.(2), line 1. After "(2)" insert " Employee Assistance Programs " and enclose "
Tang, Rui; Ma, Longfei; Xiang, Canhong; Wang, Xuedong; Li, Ang; Liao, Hongen; Dong, Jiahong
2017-09-01
Patients who undergo hilar cholangiocarcinoma (HCAC) resection with concomitant hepatectomy have a high risk of postoperative morbidity and mortality due to surgical trauma to the hepatic and biliary vasculature. A 58-year-old Chinese man with yellowing skin and sclera, abdominal distension, pruritus, and anorexia for approximately 3 weeks. Magnetic resonance cholangiopancreatography and enhanced computed tomography (CT) scanning revealed a mass over the biliary tree at the porta hepatis, which diagnosed to be s a hilar cholangiocarcinoma. Three-dimensional (3D) images of the patient's hepatic and biliary structures were reconstructed preoperatively from CT data, and the 3D images were used for preoperative planning and augmented reality (AR)-assisted intraoperative navigation during open HCAC resection with hemihepatectomy. A 3D-printed model of the patient's biliary structures was also used intraoperatively as a visual reference. No serious postoperative complications occurred, and the patient was tumor-free at the 9-month follow-up examination based on CT results. AR-assisted preoperative planning and intraoperative navigation might be beneficial in other patients with HCAC patients to reduce postoperative complications and ensure disease-free survival. In our postoperative analysis, we also found that, when the3D images were superimposed 3D-printed model using a see-through integral video graphy display device, our senses of depth perception and motion parallax were improved, compared with that which we had experienced intraoperatively using the videobased AR display system.
Application of a GPU-Assisted Maxwell Code to Electromagnetic Wave Propagation in ITER
NASA Astrophysics Data System (ADS)
Kubota, S.; Peebles, W. A.; Woodbury, D.; Johnson, I.; Zolfaghari, A.
2014-10-01
The Low Field Side Reflectometer (LSFR) on ITER is envisioned to provide capabilities for electron density profile and fluctuations measurements in both the plasma core and edge. The current design for the Equatorial Port Plug 11 (EPP11) employs seven monostatic antennas for use with both fixed-frequency and swept-frequency systems. The present work examines the characteristics of this layout using the 3-D version of the GPU-Assisted Maxwell Code (GAMC-3D). Previous studies in this area were performed with either 2-D full wave codes or 3-D ray- and beam-tracing. GAMC-3D is based on the FDTD method and can be run with either a fixed-frequency or modulated (e.g. FMCW) source, and with either a stationary or moving target (e.g. Doppler backscattering). The code is designed to run on a single NVIDIA Tesla GPU accelerator, and utilizes a technique based on the moving window method to overcome the size limitation of the onboard memory. Effects such as beam drift, linear mode conversion, and diffraction/scattering will be examined. Comparisons will be made with beam-tracing calculations using the complex eikonal method. Supported by U.S. DoE Grants DE-FG02-99ER54527 and DE-AC02-09CH11466, and the DoE SULI Program at PPPL.
Jin, Cheng; Feng, Jianjiang; Wang, Lei; Yu, Heng; Liu, Jiang; Lu, Jiwen; Zhou, Jie
2018-05-01
In this paper, we present an approach for left atrial appendage (LAA) multi-phase fast segmentation and quantitative assisted diagnosis of atrial fibrillation (AF) based on 4D-CT data. We take full advantage of the temporal dimension information to segment the living, flailed LAA based on a parametric max-flow method and graph-cut approach to build 3-D model of each phase. To assist the diagnosis of AF, we calculate the volumes of 3-D models, and then generate a "volume-phase" curve to calculate the important dynamic metrics: ejection fraction, filling flux, and emptying flux of the LAA's blood by volume. This approach demonstrates more precise results than the conventional approaches that calculate metrics by area, and allows for the quick analysis of LAA-volume pattern changes of in a cardiac cycle. It may also provide insight into the individual differences in the lesions of the LAA. Furthermore, we apply support vector machines (SVMs) to achieve a quantitative auto-diagnosis of the AF by exploiting seven features from volume change ratios of the LAA, and perform multivariate logistic regression analysis for the risk of LAA thrombosis. The 100 cases utilized in this research were taken from the Philips 256-iCT. The experimental results demonstrate that our approach can construct the 3-D LAA geometries robustly compared to manual annotations, and reasonably infer that the LAA undergoes filling, emptying and re-filling, re-emptying in a cardiac cycle. This research provides a potential for exploring various physiological functions of the LAA and quantitatively estimating the risk of stroke in patients with AF. Copyright © 2018 Elsevier Ltd. All rights reserved.
Park, Hoo Keun; Oh, Ji Hye; Kang, Heejoon; Zhang, Jian; Do, Young Rag
2015-03-04
This paper reports the combined optical effects of a two-dimensional (2D) SiNx photonic crystal layer (PCL)-assisted Lu3Al5O12:Ce (LuAG:Ce) green ceramic-plate phosphor (CPP) and a free-standing (Sr,Ca)AlSiN3:Eu red film phosphor to enhance luminous efficacy, color rendering index (CRI), and special CRI (R9) of LuAG:Ce CPP-capped white light-emitting diodes (LEDs) for high-power white LEDs at 350 mA. By introducing the 2D SiNx PCL, the luminous efficacy was improved by a factor of 1.25 and 1.15 compared to that of the conventional flat CPP-capped LED and the thickness-increased CPP-capped LED (with a thickness of 0.15 mm), respectively, while maintaining low color-rendering properties. The combining of the free-standing red film phosphor in the flat CPP-capped, the 2D PCL-assisted CPP-capped, and the thickness-increased CPP-capped LEDs led to enhancement of the CRI and the special CRI (R9); it also led to a decrease of the correlated color temperature (CCT) due to broad wavelength coverage via the addition of red emission. High CRI (94), natural white CCT (4450 K), and acceptable luminous efficacy (71.1 lm/W) were attained from the 2D PCL-assisted LuAG:Ce CPP/free-standing red film phosphor-based LED using a red phosphor concentration of 7.5 wt %. It is expected that the combination of the 2D PCL and the free-standing red film phosphor will be a good candidate for achieving a high-power white CPP-capped LED with excellent CRI.
Wang, Jian-Li; Yuan, Zi-Gang; Qian, Guo-Liang; Bao, Wu-Qiao; Jin, Guo-Liang
2018-06-01
The study aimed to develop simulation models including intracranial aneurysmal and parent vessel geometries, as well as vascular branches, through 3D printing technology. The simulation models focused on the benefits of aneurysmal treatments and clinical education. This prospective study included 13 consecutive patients who suffered from intracranial aneurysms confirmed by digital subtraction angiography (DSA) in the Neurosurgery Department of Shaoxing People's Hospital. The original 3D-DSA image data were extracted through the picture archiving and communication system and imported into Mimics. After reconstructing and transforming to Binary STL format, the simulation models of the hollow vascular tree were printed using 3D devices. The intracranial aneurysm 3D printing simulation model was developed based on DSA to assist neurosurgeons in aneurysmal treatments and residency training. Seven neurosurgical residents and 15 standardization training residents received their simulation model training and gave high assessments for the educational course with the follow-up qualitative questionnaire. 3D printed simulation models based on DSA can perfectly reveal target aneurysms and help neurosurgeons select therapeutic strategies precisely. As an educational tool, the 3D aneurysm vascular simulation model is useful for training residents.
Parallax barrier engineering for image quality improvement in an autostereoscopic 3D display.
Kim, Sung-Kyu; Yoon, Ki-Hyuk; Yoon, Seon Kyu; Ju, Heongkyu
2015-05-18
We present a image quality improvement in a parallax barrier (PB)-based multiview autostereoscopic 3D display system under a real-time tracking of positions of a viewer's eyes. The system presented exploits a parallax barrier engineered to offer significantly improved quality of three-dimensional images for a moving viewer without an eyewear under the dynamic eye tracking. The improved image quality includes enhanced uniformity of image brightness, reduced point crosstalk, and no pseudoscopic effects. We control the relative ratio between two parameters i.e., a pixel size and the aperture of a parallax barrier slit to improve uniformity of image brightness at a viewing zone. The eye tracking that monitors positions of a viewer's eyes enables pixel data control software to turn on only pixels for view images near the viewer's eyes (the other pixels turned off), thus reducing point crosstalk. The eye tracking combined software provides right images for the respective eyes, therefore producing no pseudoscopic effects at its zone boundaries. The viewing zone can be spanned over area larger than the central viewing zone offered by a conventional PB-based multiview autostereoscopic 3D display (no eye tracking). Our 3D display system also provides multiviews for motion parallax under eye tracking. More importantly, we demonstrate substantial reduction of point crosstalk of images at the viewing zone, its level being comparable to that of a commercialized eyewear-assisted 3D display system. The multiview autostereoscopic 3D display presented can greatly resolve the point crosstalk problem, which is one of the critical factors that make it difficult for previous technologies for a multiview autostereoscopic 3D display to replace an eyewear-assisted counterpart.
CRAVAT is an easy to use web-based tool for analysis of cancer variants (missense, nonsense, in-frame indel, frameshift indel, splice site). CRAVAT provides scores and a variety of annotations that assist in identification of important variants. Results are provided in an interactive, highly graphical webpage and include annotated 3D structure visualization. CRAVAT is also available for local or cloud-based installation as a Docker container. MuPIT provides 3D visualization of mutation clusters and functional annotation and is now integrated with CRAVAT.
Phan, Philippe; Mezghani, Neila; Aubin, Carl-Éric; de Guise, Jacques A; Labelle, Hubert
2011-07-01
Adolescent idiopathic scoliosis (AIS) is a complex spinal deformity whose assessment and treatment present many challenges. Computer applications have been developed to assist clinicians. A literature review on computer applications used in AIS evaluation and treatment has been undertaken. The algorithms used, their accuracy and clinical usability were analyzed. Computer applications have been used to create new classifications for AIS based on 2D and 3D features, assess scoliosis severity or risk of progression and assist bracing and surgical treatment. It was found that classification accuracy could be improved using computer algorithms that AIS patient follow-up and screening could be done using surface topography thereby limiting radiation and that bracing and surgical treatment could be optimized using simulations. Yet few computer applications are routinely used in clinics. With the development of 3D imaging and databases, huge amounts of clinical and geometrical data need to be taken into consideration when researching and managing AIS. Computer applications based on advanced algorithms will be able to handle tasks that could otherwise not be done which can possibly improve AIS patients' management. Clinically oriented applications and evidence that they can improve current care will be required for their integration in the clinical setting.
NASA Astrophysics Data System (ADS)
Rudolph, Tobias; Ebert, Lars; Kowal, Jens
2006-03-01
Supporting surgeons in performing minimally invasive surgeries can be considered as one of the major goals of computer assisted surgery. Excellent intraoperative visualization is a prerequisite to achieve this aim. The Siremobil Iso-C 3D has become a widely used imaging device, which, in combination with a navigation system, enables the surgeon to directly navigate within the acquired 3D image volume without any extra registration steps. However, the image quality is rather low compared to a CT scan and the volume size (approx. 12 cm 3) limits its application. A regularly used alternative in computer assisted orthopedic surgery is to use of a preoperatively acquired CT scan to visualize the operating field. But, the additional registration step, necessary in order to use CT stacks for navigation is quite invasive. Therefore the objective of this work is to develop a noninvasive registration technique. In this article a solution is being proposed that registers a preoperatively acquired CT scan to the intraoperatively acquired Iso-C 3D image volume, thereby registering the CT to the tracked anatomy. The procedure aligns both image volumes by maximizing the mutual information, an algorithm that has already been applied to similar registration problems and demonstrated good results. Furthermore the accuracy of such a registration method was investigated in a clinical setup, integrating a navigated Iso-C 3D in combination with an tracking system. Initial tests based on cadaveric animal bone resulted in an accuracy ranging from 0.63mm to 1.55mm mean error.
HÖHN, K.; FUCHS, J.; FRÖBER, A.; KIRMSE, R.; GLASS, B.; ANDERS‐ÖSSWEIN, M.; WALTHER, P.; KRÄUSSLICH, H.‐G.
2015-01-01
Summary In this study, we present a correlative microscopy workflow to combine detailed 3D fluorescence light microscopy data with ultrastructural information gained by 3D focused ion beam assisted scanning electron microscopy. The workflow is based on an optimized high pressure freezing/freeze substitution protocol that preserves good ultrastructural detail along with retaining the fluorescence signal in the resin embedded specimens. Consequently, cellular structures of interest can readily be identified and imaged by state of the art 3D confocal fluorescence microscopy and are precisely referenced with respect to an imprinted coordinate system on the surface of the resin block. This allows precise guidance of the focused ion beam assisted scanning electron microscopy and limits the volume to be imaged to the structure of interest. This, in turn, minimizes the total acquisition time necessary to conduct the time consuming ultrastructural scanning electron microscope imaging while eliminating the risk to miss parts of the target structure. We illustrate the value of this workflow for targeting virus compartments, which are formed in HIV‐pulsed mature human dendritic cells. PMID:25786567
NASA Astrophysics Data System (ADS)
Qi, Yulin; Müller, Miriam; Stokes, Caroline S.; Volmer, Dietrich A.
2018-04-01
LC-MS/MS is widely utilized today for quantification of vitamin D in biological fluids. Mass spectrometric assays for vitamin D require very careful method optimization for precise and interference-free, accurate analyses however. Here, we explore chemical derivatization and matrix-assisted laser desorption/ionization (MALDI) as a rapid alternative for quantitative measurement of 25-hydroxyvitamin D3 in human serum, and compare it to results from LC-MS/MS. The method implemented an automated imaging step of each MALDI spot, to locate areas of high intensity, avoid sweet spot phenomena, and thus improve precision. There was no statistically significant difference in vitamin D quantification between the MALDI-MS/MS and LC-MS/MS: mean ± standard deviation for MALDI-MS—29.4 ± 10.3 ng/mL—versus LC-MS/MS—30.3 ± 11.2 ng/mL (P = 0.128)—for the sum of the 25-hydroxyvitamin D epimers. The MALDI-based assay avoided time-consuming chromatographic separation steps and was thus much faster than the LC-MS/MS assay. It also consumed less sample, required no organic solvents, and was readily automated. In this proof-of-concept study, MALDI-MS readily demonstrated its potential for mass spectrometric quantification of vitamin D compounds in biological fluids.
3D Printing of Plant Golgi Stacks from Their Electron Tomographic Models.
Mai, Keith Ka Ki; Kang, Madison J; Kang, Byung-Ho
2017-01-01
Three-dimensional (3D) printing is an effective tool for preparing tangible 3D models from computer visualizations to assist in scientific research and education. With the recent popularization of 3D printing processes, it is now possible for individual laboratories to convert their scientific data into a physical form suitable for presentation or teaching purposes. Electron tomography is an electron microscopy method by which 3D structures of subcellular organelles or macromolecular complexes are determined at nanometer-level resolutions. Electron tomography analyses have revealed the convoluted membrane architectures of Golgi stacks, chloroplasts, and mitochondria. But the intricacy of their 3D organizations is difficult to grasp from tomographic models illustrated on computer screens. Despite the rapid development of 3D printing technologies, production of organelle models based on experimental data with 3D printing has rarely been documented. In this chapter, we present a simple guide to creating 3D prints of electron tomographic models of plant Golgi stacks using the two most accessible 3D printing technologies.
Testing of a novel pin array guide for accurate three-dimensional glenoid component positioning.
Lewis, Gregory S; Stevens, Nicole M; Armstrong, April D
2015-12-01
A substantial challenge in total shoulder replacement is accurate positioning and alignment of the glenoid component. This challenge arises from limited intraoperative exposure and complex arthritic-driven deformity. We describe a novel pin array guide and method for patient-specific guiding of the glenoid central drill hole. We also experimentally tested the hypothesis that this method would reduce errors in version and inclination compared with 2 traditional methods. Polymer models of glenoids were created from computed tomography scans from 9 arthritic patients. Each 3-dimensional (3D) printed scapula was shrouded to simulate the operative situation. Three different methods for central drill alignment were tested, all with the target orientation of 5° retroversion and 0° inclination: no assistance, assistance by preoperative 3D imaging, and assistance by the pin array guide. Version and inclination errors of the drill line were compared. Version errors using the pin array guide (3° ± 2°) were significantly lower than version errors associated with no assistance (9° ± 7°) and preoperative 3D imaging (8° ± 6°). Inclination errors were also significantly lower using the pin array guide compared with no assistance. The new pin array guide substantially reduced errors in orientation of the central drill line. The guide method is patient specific but does not require rapid prototyping and instead uses adjustments to an array of pins based on automated software calculations. This method may ultimately provide a cost-effective solution enabling surgeons to obtain accurate orientation of the glenoid. Copyright © 2015 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.
Three-dimensional simulation, surgical navigation and thoracoscopic lung resection
Kanzaki, Masato; Kikkawa, Takuma; Sakamoto, Kei; Maeda, Hideyuki; Wachi, Naoko; Komine, Hiroshi; Oyama, Kunihiro; Murasugi, Masahide; Onuki, Takamasa
2013-01-01
This report describes a 3-dimensional (3-D) video-assisted thoracoscopic lung resection guided by a 3-D video navigation system having a patient-specific 3-D reconstructed pulmonary model obtained by preoperative simulation. A 78-year-old man was found to have a small solitary pulmonary nodule in the left upper lobe in chest computed tomography. By a virtual 3-D pulmonary model the tumor was found to be involved in two subsegments (S1 + 2c and S3a). Complete video-assisted thoracoscopic surgery bi-subsegmentectomy was selected in simulation and was performed with lymph node dissection. A 3-D digital vision system was used for 3-D thoracoscopic performance. Wearing 3-D glasses, the patient's actual reconstructed 3-D model on 3-D liquid-crystal displays was observed, and the 3-D intraoperative field and the picture of 3-D reconstructed pulmonary model were compared. PMID:24964426
NASA Astrophysics Data System (ADS)
Wu, Shide; Su, Fangfang; Dong, Xiaodong; Ma, Chuang; Pang, Long; Peng, Donglai; Wang, Minghua; He, Linghao; Zhang, Zhihong
2017-04-01
A biosensor based on the plasma polyaniline (pPANI)-modified tin oxide and 3D reduced graphene oxide (SnO2@3D-rGO) nanocomposite was fabricated to detect glucose. The SnO2@3D-rGO nanocomposite was synthesized by simultaneously reducing 3D graphene oxide (3D-GO) and translating SnCl4 into SnO2, followed by pPANI modification. The content of amino groups in the SnO2@3D-rGO@pPANI nanocomposites depended on the plasma input powers used in plasma deposition. The SnO2@3D-rGO nanocomposite was important in the electrochemical biosensor to detect glucose. The fabricated biosensor exhibited a much higher sensitivity than that formed from individual components, namely, SnO2@3D-rGO and pPANI. This biosensor demonstrated a low detection limit of 0.047 ng mL-1 (0.26 nM) (S/N = 3) within the concentration range of 0.1 ng mL-1 to 5 μg mL-1. The selectivity, stability, and practicality of the SnO2@3D-rGO@pPANI-based biosensor were observed. In conclusion, the plasma surface-modified nanocomposite is a promising candidate as biosensor for glucose detection and biological diagnosis.
Additive manufacturing: From implants to organs.
Douglas, Tania S
2014-05-12
Additive manufacturing (AM) constructs 3D objects layer by layer under computer control from 3D models. 3D printing is one example of this kind of technology. AM offers geometric flexibility in its products and therefore allows customisation to suit individual needs. Clinical success has been shown with models for surgical planning, implants, assistive devices and scaffold-based tissue engineering. The use of AM to print tissues and organs that mimic nature in structure and function remains an elusive goal, but has the potential to transform personalised medicine, drug development and scientific understanding of the mechanisms of disease.
3D Fiber Orientation Simulation for Plastic Injection Molding
NASA Astrophysics Data System (ADS)
Lin, Baojiu; Jin, Xiaoshi; Zheng, Rong; Costa, Franco S.; Fan, Zhiliang
2004-06-01
Glass fiber reinforced polymer is widely used in the products made using injection molding processing. The distribution of fiber orientation inside plastic parts has direct effects on quality of molded parts. Using computer simulation to predict fiber orientation distribution is one of most efficient ways to assist engineers to do warpage analysis and to find a good design solution to produce high quality plastic parts. Fiber orientation simulation software based on 2-1/2D (midplane /Dual domain mesh) techniques has been used in industry for a decade. However, the 2-1/2D technique is based on the planar Hele-Shaw approximation and it is not suitable when the geometry has complex three-dimensional features which cannot be well approximated by 2D shells. Recently, a full 3D simulation software for fiber orientation has been developed and integrated into Moldflow Plastics Insight 3D simulation software. The theory for this new 3D fiber orientation calculation module is described in this paper. Several examples are also presented to show the benefit in using 3D fiber orientation simulation.
Zhou, Wen; Li, Xinying; Yu, Jianjun
2017-10-30
We propose QPSK millimeter-wave (mm-wave) vector signal generation for D-band based on balanced precoding-assisted photonic frequency quadrupling technology employing a single intensity modulator without an optical filter. The intensity MZM is driven by a balanced pre-coding 37-GHz QPSK RF signal. The modulated optical subcarriers are directly sent into the single ended photodiode to generate 148-GHz QPSK vector signal. We experimentally demonstrate 1-Gbaud 148-GHz QPSK mm-wave vector signal generation, and investigate the bit-error-rate (BER) performance of the vector signals at 148-GHz. The experimental results show that the BER value can be achieved as low as 1.448 × 10 -3 when the optical power into photodiode is 8.8dBm. To the best of our knowledge, it is the first time to realize the frequency-quadrupling vector mm-wave signal generation at D-band based on only one MZM without an optical filter.
Muratov, Eugene; Lewis, Margaret; Fourches, Denis; Tropsha, Alexander; Cox, Wendy C
2017-04-01
Objective. To develop predictive computational models forecasting the academic performance of students in the didactic-rich portion of a doctor of pharmacy (PharmD) curriculum as admission-assisting tools. Methods. All PharmD candidates over three admission cycles were divided into two groups: those who completed the PharmD program with a GPA ≥ 3; and the remaining candidates. Random Forest machine learning technique was used to develop a binary classification model based on 11 pre-admission parameters. Results. Robust and externally predictive models were developed that had particularly high overall accuracy of 77% for candidates with high or low academic performance. These multivariate models were highly accurate in predicting these groups to those obtained using undergraduate GPA and composite PCAT scores only. Conclusion. The models developed in this study can be used to improve the admission process as preliminary filters and thus quickly identify candidates who are likely to be successful in the PharmD curriculum.
Final Progress Report: Developing Ethical Practices for Genetics Testing in the Workplace
DOE Office of Scientific and Technical Information (OSTI.GOV)
Laura Roberts, MD; Teddy Warner, PhD
Our multidisciplinary research team for this project involved collaboration between the Department of Psychiatry and Behavioral Medicine at the Medical College of Wisconsin (MCW) and the Department of Family and Community Medicine at the University of New Mexico Health Sciences Center (UNM HSC). Our research team in Wisconsin was led by Laura Roberts, M.D., Principal Investigator, and included Scott Helberg, MLS (Project Coordinator), Kate Green Hammond, Ph.D. (Consultant), Krisy Edenharder (Research Coordinator), and Mark Talatzko (Research Assistant). Our New Mexico-based team was led by Teddy Warner, Ph.D., Co-Principal Investigator and UNM Site Principal Investigator, and included Suzanne Roybal (Project Assistant),more » Darlyn Mabon (Project Assistant), Kate Green Hammond, PhD (Senior Research Scientist on the UNM team from 2004 until January, 2007), and Paulette Christopher (Research Assistant). In addition, computer technical and web support for the web-based survey conducted on a secure server at the University of New Mexico was provided by Kevin Wiley and Kim Hagen of the Systems and Programming Team of the Health Sciences Center Library and Information Center. We stated 3 aims in the grant proposal: (1) To collect web survey reports of the ethical perspectives, concerns, preferences and decision-making related to genetic testing using surveys from employees at: (a) Los Alamos National Laboratory (LANL); (b) Sandia National Laboratories (SNL); and (c) the University of New Mexico Health Sciences Center (UNMHSC); (2) To perform an extensive literature search and the extant survey data to develop evidence-based policy recommendations for ethically sound genetic testing associated with research and occupational health activities in the workplace; and, (3) To host a conference at the Medical College of Wisconsin to provide employers, workers, health professionals, researchers, the public, and the media an opportunity to consider ethical issues involved in genetic testing in the context of the workplace.« less
Tang, Rui; Ma, Longfei; Xiang, Canhong; Wang, Xuedong; Li, Ang; Liao, Hongen; Dong, Jiahong
2017-01-01
Abstract Rationale: Patients who undergo hilar cholangiocarcinoma (HCAC) resection with concomitant hepatectomy have a high risk of postoperative morbidity and mortality due to surgical trauma to the hepatic and biliary vasculature. Patient concerns: A 58-year-old Chinese man with yellowing skin and sclera, abdominal distension, pruritus, and anorexia for approximately 3 weeks. Diagnoses: Magnetic resonance cholangiopancreatography and enhanced computed tomography (CT) scanning revealed a mass over the biliary tree at the porta hepatis, which diagnosed to be s a hilar cholangiocarcinoma. Intervention: Three-dimensional (3D) images of the patient's hepatic and biliary structures were reconstructed preoperatively from CT data, and the 3D images were used for preoperative planning and augmented reality (AR)-assisted intraoperative navigation during open HCAC resection with hemihepatectomy. A 3D-printed model of the patient's biliary structures was also used intraoperatively as a visual reference. Outcomes: No serious postoperative complications occurred, and the patient was tumor-free at the 9-month follow-up examination based on CT results. Lessons: AR-assisted preoperative planning and intraoperative navigation might be beneficial in other patients with HCAC patients to reduce postoperative complications and ensure disease-free survival. In our postoperative analysis, we also found that, when the3D images were superimposed 3D-printed model using a see-through integral video graphy display device, our senses of depth perception and motion parallax were improved, compared with that which we had experienced intraoperatively using the videobased AR display system. PMID:28906410
3D Nanofabrication Using AFM-Based Ultrasonic Vibration Assisted Nanomachining
NASA Astrophysics Data System (ADS)
Deng, Jia
Nanolithography and nanofabrication processes have significant impact on the recent development of fundamental research areas such as physics, chemistry and biology, as well as the modern electronic devices that have reached nanoscale domain such as optoelectronic devices. Many advanced nanofabrication techniques have been developed and reported to satisfy different requirements in both research areas and applications such as electron-beam lithography. However, it is expensive to use and maintain the equipment. Atomic Force Microscope (AFM) based nanolithography processes provide an alternative approach to nanopatterning with significantly lower cost. Recently, three dimensional nanostructures have attracted a lot of attention, motivated by many applications in various fields including optics, plasmonics and nanoelectromechanical systems. AFM nanolithography processes are able to create not only two dimensional nanopatterns but also have the great potential to fabricate three dimensional nanostructures. The objectives of this research proposal are to investigate the capability of AFM-based three dimensional nanofabrication processes, to transfer the three dimensional nanostructures from resists to silicon surfaces and to use the three dimensional nanostructures on silicon in applications. Based on the understanding of literature, a novel AFM-based ultrasonic vibration assisted nanomachining system is utilized to develop three dimensional nanofabrication processes. In the system, high-frequency in plane circular xy-vibration was introduced to create a virtual tool, whose diameter is controlled by the amplitude of xy-vibration and is larger than that of a regular AFM tip. Therefore, the feature width of a single trench is tunable. Ultrasonic vibration of sample in z-direction was introduced to control the depth of single trenches, creating a high-rate 3D nanomachining process. Complicated 3D nanostructures on PMMA are fabricated under both the setpoint force and z-height control modes. Complex contours and both discrete and continuous height changes are able to be fabricated by the novel 3D nanofabrication processes. Results are imaged clearly after cleaning the debris covering on the 3D nanostructures after nanomachining process. The process is validated by fabricating various 3D nanostructures. The advantages and disadvantages are compared between these two control modes. Furthermore, the 3D nanostructures were further transferred from PMMA surfaces onto silicon surfaces using reactive ion etching (RIE) process. Recipes are developed based on the functionality of the etching gas in the transfer process. Tunable selectivity and controllable surface finishes are achieved by varying the flow rate of oxygen. The developed 3D nanofabrication process is used as a novel technique in two applications, master fabrication for soft lithography and SERS substrates fabrication. 3D nanostructures were reversely molded on PDMS and then duplicated on new PMMA substrates. 3D nanostructures are fabricated, which can be either directly used or transferred on silicon as SERS substrates after coating 80 nm gold layers. They greatly enhanced the intensity of Raman scattering with the enhancement factor of 3.11x103. These applications demonstrate the capability of the novel process of AFM-based 3D nanomachining.
Wieringa, Fokko P.; Bouma, Henri; Eendebak, Pieter T.; van Basten, Jean-Paul A.; Beerlage, Harrie P.; Smits, Geert A. H. J.; Bos, Jelte E.
2014-01-01
Abstract. In comparison to open surgery, endoscopic surgery offers impaired depth perception and narrower field-of-view. To improve depth perception, the Da Vinci robot offers three-dimensional (3-D) video on the console for the surgeon but not for assistants, although both must collaborate. We improved the shared perception of the whole surgical team by connecting live 3-D monitors to all three available Da Vinci generations, probed user experience after two years by questionnaire, and compared time measurements of a predefined complex interaction task performed with a 3-D monitor versus two-dimensional. Additionally, we investigated whether the complex mental task of reconstructing a 3-D overview from an endoscopic video can be performed by a computer and shared among users. During the study, 925 robot-assisted laparoscopic procedures were performed in three hospitals, including prostatectomies, cystectomies, and nephrectomies. Thirty-one users participated in our questionnaire. Eighty-four percent preferred 3-D monitors and 100% reported spatial-perception improvement. All participating urologists indicated quicker performance of tasks requiring delicate collaboration (e.g., clip placement) when assistants used 3-D monitors. Eighteen users participated in a timing experiment during a delicate cooperation task in vitro. Teamwork was significantly (40%) faster with the 3-D monitor. Computer-generated 3-D reconstructions from recordings offered very wide interactive panoramas with educational value, although the present embodiment is vulnerable to movement artifacts. PMID:26158026
Image-based computer-assisted diagnosis system for benign paroxysmal positional vertigo
NASA Astrophysics Data System (ADS)
Kohigashi, Satoru; Nakamae, Koji; Fujioka, Hiromu
2005-04-01
We develop the image based computer assisted diagnosis system for benign paroxysmal positional vertigo (BPPV) that consists of the balance control system simulator, the 3D eye movement simulator, and the extraction method of nystagmus response directly from an eye movement image sequence. In the system, the causes and conditions of BPPV are estimated by searching the database for record matching with the nystagmus response for the observed eye image sequence of the patient with BPPV. The database includes the nystagmus responses for simulated eye movement sequences. The eye movement velocity is obtained by using the balance control system simulator that allows us to simulate BPPV under various conditions such as canalithiasis, cupulolithiasis, number of otoconia, otoconium size, and so on. Then the eye movement image sequence is displayed on the CRT by the 3D eye movement simulator. The nystagmus responses are extracted from the image sequence by the proposed method and are stored in the database. In order to enhance the diagnosis accuracy, the nystagmus response for a newly simulated sequence is matched with that for the observed sequence. From the matched simulation conditions, the causes and conditions of BPPV are estimated. We apply our image based computer assisted diagnosis system to two real eye movement image sequences for patients with BPPV to show its validity.
NASA Astrophysics Data System (ADS)
Liu, Zhi; Zhou, Baotong; Zhang, Changnian
2017-03-01
Vehicle-mounted panoramic system is important safety assistant equipment for driving. However, traditional systems only render fixed top-down perspective view of limited view field, which may have potential safety hazard. In this paper, a texture mapping algorithm for 3D vehicle-mounted panoramic system is introduced, and an implementation of the algorithm utilizing OpenGL ES library based on Android smart platform is presented. Initial experiment results show that the proposed algorithm can render a good 3D panorama, and has the ability to change view point freely.
Liu, Xin; Zeng, Can-Jun; Lu, Jian-Sen; Lin, Xu-Chen; Huang, Hua-Jun; Tan, Xin-Yu; Cai, Dao-Zhang
2017-03-20
To evaluate the feasibility and effectiveness of using 3D printing and computer-assisted surgical simulation in preoperative planning for acetabular fractures. A retrospective analysis was performed in 53 patients with pelvic fracture, who underwent surgical treatment between September, 2013 and December, 2015 with complete follow-up data. Among them, 19 patients were treated with CT three-dimensional reconstruction, computer-assisted virtual reset internal fixation, 3D model printing, and personalized surgery simulation before surgery (3D group), and 34 patients underwent routine preoperative examination (conventional group). The intraoperative blood loss, transfusion volume, times of intraoperative X-ray, operation time, Matta score and Merle D' Aubigne & Postel score were recorded in the 2 groups. Preoperative planning and postoperative outcomes in the two groups were compared. All the operations were completed successfully. In 3D group, significantly less intraoperative blood loss, transfusion volume, fewer times of X-ray, and shortened operation time were recorded compared with those in the conventional group (P<0.05). According to the Matta scores, excellent or good fracture reduction was achieved in 94.7% (18/19) of the patients in 3D group and in 82.4% (28/34) of the patients in conventional group; the rates of excellent and good hip function at the final follow-up were 89.5% (17/19) in the 3D group and 85.3% (29/34) in the conventional group (P>0.05). In the 3D group, the actual internal fixation well matched the preoperative design. 3D printing and computer-assisted surgical simulation for preoperative planning is feasible and accurate for management of acetabular fracture and can effectively improve the operation efficiency.
Computer-assisted spinal osteotomy: a technical note and report of four cases.
Fujibayashi, Shunsuke; Neo, Masashi; Takemoto, Mitsuru; Ota, Masato; Nakayama, Tomitaka; Toguchida, Junya; Nakamura, Takashi
2010-08-15
A report of 4 cases of spinal osteotomy performed under the guidance of a computer-assisted navigation system and a technical note about the use of the navigation system for spinal osteotomy. To document the surgical technique and usefulness of computer-assisted surgery for spinal osteotomy. A computer-assisted navigation system provides accurate 3-dimensional (3D) real-time surgical information during the operation. Although there are many reports on the accuracy and usefulness of a navigation system for pedicle screw placement, there are few reports on the application for spinal osteotomy. We report on 4 complex cases including 3 solitary malignant spinal tumors and 1 spinal kyphotic deformity of ankylosing spondylitis, which were treated surgically using a computer-assisted spinal osteotomy. The surgical technique and postoperative clinical and radiologic results are presented. 3D spinal osteotomy under the guidance of a computer-assisted navigation system was performed successfully in 4 patients. All malignant tumors were resected en bloc, and the spinal deformity was corrected precisely according to the preoperative plan. Pathologic analysis confirmed the en bloc resection without tumor exposure in the 3 patients with a spinal tumor. The use of a computer-assisted navigation system will help ensure the safety and efficacy of a complex 3D spinal osteotomy.
Sorkio, Anni; Koch, Lothar; Koivusalo, Laura; Deiwick, Andrea; Miettinen, Susanna; Chichkov, Boris; Skottman, Heli
2018-07-01
There is a high demand for developing methods to produce more native-like 3D corneal structures. In the present study, we produced 3D cornea-mimicking tissues using human stem cells and laser-assisted bioprinting (LaBP). Human embryonic stem cell derived limbal epithelial stem cells (hESC-LESC) were used as a cell source for printing epithelium-mimicking structures, whereas human adipose tissue derived stem cells (hASCs) were used for constructing layered stroma-mimicking structures. The development and optimization of functional bioinks was a crucial step towards successful bioprinting of 3D corneal structures. Recombinant human laminin and human sourced collagen I served as the bases for the functional bioinks. We used two previously established LaBP setups based on laser induced forward transfer, with different laser wavelengths and appropriate absorption layers. We bioprinted three types of corneal structures: stratified corneal epithelium using hESC-LESCs, lamellar corneal stroma using alternating acellular layers of bioink and layers with hASCs, and finally structures with both a stromal and epithelial part. The printed constructs were evaluated for their microstructure, cell viability and proliferation, and key protein expression (Ki67, p63α, p40, CK3, CK15, collagen type I, VWF). The 3D printed stromal constructs were also implanted into porcine corneal organ cultures. Both cell types maintained good viability after printing. Laser-printed hESC-LESCs showed epithelial cell morphology, expression of Ki67 proliferation marker and co-expression of corneal progenitor markers p63α and p40. Importantly, the printed hESC-LESCs formed a stratified epithelium with apical expression of CK3 and basal expression of the progenitor markers. The structure of the 3D bioprinted stroma demonstrated that the hASCs had organized horizontally as in the native corneal stroma and showed positive labeling for collagen I. After 7 days in porcine organ cultures, the 3D bioprinted stromal structures attached to the host tissue with signs of hASCs migration from the printed structure. This is the first study to demonstrate the feasibility of 3D LaBP for corneal applications using human stem cells and successful fabrication of layered 3D bioprinted tissues mimicking the structure of the native corneal tissue. Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.
Archavlis, Eleftherios; Schwandt, Eike; Kosterhon, Michael; Gutenberg, Angelika; Ulrich, Peter; Nimer, Amr; Giese, Alf; Kantelhardt, Sven Rainer
2016-07-01
The main difficulties of transpedicular corpectomies are lack of space for vertebral body replacement in the neighborhood of critical structures, the necessity for sacrifice of nerve roots in the thoracic spine. and the extent of hemorrhage due to venous epidural bleeding. We present a modified technique of transpedicular corpectomy by using an endoscopic-assisted microsurgical technique performed through a single posterior approach. A 3-dimensional (3D) preoperative reconstruction could be helpful in the planning for this complex anatomic region. Surface and volume 3D reconstruction were performed by Amira or the Dextroscope. The clinical experience of this study includes 7 cases, 2 with an unstable burst fracture and 5 with metastatic destructive vertebral body disease, all with significant retropulsion and obstruction of the spinal canal. We performed a comparison with a conventional cohort of transpedicular thoracic corpectomies. Qualitative parameters of the 3D virtual reality planning included degree of bone removal and distance from critical structures such as myelon and implant diameter. Parameters were met in each case, with demonstration of optimal positioning of the implant without neurological complications. In all patients, the endoscope was a significant help in identifying the origins of active bleeding, residual tumor, extent of bone removal, facilitating cage insertion in a minimally invasive way, and helping to avoid root sacrifice on both sides. Microsurgical endoscopic-assisted transpedicular corpectomy may prove valuable in enhancing the safety of corpectomy in destructive vertebral body disease. The 3D virtual anatomic model greatly facilitated the preoperative planning. Copyright © 2016 Elsevier Inc. All rights reserved.
Liu, Hongwei; Weng, Yiping; Zhang, Yunkun; Xu, Nanwei; Tong, Jing; Wang, Caimei
2015-09-01
To study the feasibility of preparation of the individualized femoral prosthesis through computer assisted design and electron beammelting rapid prototyping (EBM-RP) metal three-dimensional (3D) printing technology. One adult male left femur specimen was used for scanning with 64-slice spiral CT; tomographic image data were imported into Mimics15.0 software to reconstruct femoral 3D model, then the 3D model of individualized femoral prosthesis was designed through UG8.0 software. Finally the 3D model data were imported into EBM-RP metal 3D printer to print the individualized sleeve. According to the 3D model of individualized prosthesis, customized sleeve was successfully prepared through the EBM-RP metal 3D printing technology, assembled with the standard handle component of SR modular femoral prosthesis to make the individualized femoral prosthesis. Customized femoral prosthesis accurately matching with metaphyseal cavity can be designed through the thin slice CT scanning and computer assisted design technology. Titanium alloy personalized prosthesis with complex 3D shape, pore surface, and good matching with metaphyseal cavity can be manufactured by the technology of EBM-RP metal 3D printing, and the technology has convenient, rapid, and accurate advantages.
Augmented reality and haptic interfaces for robot-assisted surgery.
Yamamoto, Tomonori; Abolhassani, Niki; Jung, Sung; Okamura, Allison M; Judkins, Timothy N
2012-03-01
Current teleoperated robot-assisted minimally invasive surgical systems do not take full advantage of the potential performance enhancements offered by various forms of haptic feedback to the surgeon. Direct and graphical haptic feedback systems can be integrated with vision and robot control systems in order to provide haptic feedback to improve safety and tissue mechanical property identification. An interoperable interface for teleoperated robot-assisted minimally invasive surgery was developed to provide haptic feedback and augmented visual feedback using three-dimensional (3D) graphical overlays. The software framework consists of control and command software, robot plug-ins, image processing plug-ins and 3D surface reconstructions. The feasibility of the interface was demonstrated in two tasks performed with artificial tissue: palpation to detect hard lumps and surface tracing, using vision-based forbidden-region virtual fixtures to prevent the patient-side manipulator from entering unwanted regions of the workspace. The interoperable interface enables fast development and successful implementation of effective haptic feedback methods in teleoperation. Copyright © 2011 John Wiley & Sons, Ltd.
Plancoulaine, Benoît; Laurinaviciene, Aida; Meskauskas, Raimundas; Baltrusaityte, Indra; Besusparis, Justinas; Herlin, Paulette; Laurinavicius, Arvydas
2014-01-01
Digital image analysis (DIA) enables better reproducibility of immunohistochemistry (IHC) studies. Nevertheless, accuracy of the DIA methods needs to be ensured, demanding production of reference data sets. We have reported on methodology to calibrate DIA for Ki67 IHC in breast cancer tissue based on reference data obtained by stereology grid count. To produce the reference data more efficiently, we propose digital IHC wizard generating initial cell marks to be verified by experts. Digital images of proliferation marker Ki67 IHC from 158 patients (one tissue microarray spot per patient) with an invasive ductal carcinoma of the breast were used. Manual data (mD) were obtained by marking Ki67-positive and negative tumour cells, using a stereological method for 2D object enumeration. DIA was used as an initial step in stereology grid count to generate the digital data (dD) marks by Aperio Genie and Nuclear algorithms. The dD were collected into XML files from the DIA markup images and overlaid on the original spots along with the stereology grid. The expert correction of the dD marks resulted in corrected data (cD). The percentages of Ki67 positive tumour cells per spot in the mD, dD, and cD sets were compared by single linear regression analysis. Efficiency of cD production was estimated based on manual editing effort. The percentage of Ki67-positive tumor cells was in very good agreement in the mD, dD, and cD sets: regression of cD from dD (R2=0.92) reflects the impact of the expert editing the dD as well as accuracy of the DIA used; regression of the cD from the mD (R2=0.94) represents the consistency of the DIA-assisted ground truth (cD) with the manual procedure. Nevertheless, the accuracy of detection of individual tumour cells was much lower: in average, 18 and 219 marks per spot were edited due to the Genie and Nuclear algorithm errors, respectively. The DIA-assisted cD production in our experiment saved approximately 2/3 of manual marking. Digital IHC wizard enabled DIA-assisted stereology to produce reference data in a consistent and efficient way. It can provide quality control measure for appraising accuracy of the DIA steps.
2014-01-01
Background Digital image analysis (DIA) enables better reproducibility of immunohistochemistry (IHC) studies. Nevertheless, accuracy of the DIA methods needs to be ensured, demanding production of reference data sets. We have reported on methodology to calibrate DIA for Ki67 IHC in breast cancer tissue based on reference data obtained by stereology grid count. To produce the reference data more efficiently, we propose digital IHC wizard generating initial cell marks to be verified by experts. Methods Digital images of proliferation marker Ki67 IHC from 158 patients (one tissue microarray spot per patient) with an invasive ductal carcinoma of the breast were used. Manual data (mD) were obtained by marking Ki67-positive and negative tumour cells, using a stereological method for 2D object enumeration. DIA was used as an initial step in stereology grid count to generate the digital data (dD) marks by Aperio Genie and Nuclear algorithms. The dD were collected into XML files from the DIA markup images and overlaid on the original spots along with the stereology grid. The expert correction of the dD marks resulted in corrected data (cD). The percentages of Ki67 positive tumour cells per spot in the mD, dD, and cD sets were compared by single linear regression analysis. Efficiency of cD production was estimated based on manual editing effort. Results The percentage of Ki67-positive tumor cells was in very good agreement in the mD, dD, and cD sets: regression of cD from dD (R2=0.92) reflects the impact of the expert editing the dD as well as accuracy of the DIA used; regression of the cD from the mD (R2=0.94) represents the consistency of the DIA-assisted ground truth (cD) with the manual procedure. Nevertheless, the accuracy of detection of individual tumour cells was much lower: in average, 18 and 219 marks per spot were edited due to the Genie and Nuclear algorithm errors, respectively. The DIA-assisted cD production in our experiment saved approximately 2/3 of manual marking. Conclusions Digital IHC wizard enabled DIA-assisted stereology to produce reference data in a consistent and efficient way. It can provide quality control measure for appraising accuracy of the DIA steps. PMID:25565221
Anssari Moin, David; Derksen, Wiebe; Waars, Hugo; Hassan, Bassam; Wismeijer, Daniel
2017-05-01
The aim of this study was to introduce a new concept for computer-assisted template-guided placement of a custom 3D-designed/3D-printed implant with congruent custom 3D-designed/3D-printed surgical tooling and to test the feasibility and accuracy of this method in-vitro. One partially edentulous human mandibular cadaver was scanned with a cone-beam computed tomography (CBCT) system and intra-oral scan system. The 3D data of this cadaver were imported in specialized software and used to analyse the region of a missing tooth. Based on the functional and anatomical parameters, an individual implant with congruent surgical tooling and surgical guided template was designed and 3D-printed. The guided osteotomy was performed, and the custom implant inserted. To evaluate the planned implant position in comparison with the placed implant position, the mandible with implant was scanned again with the CBCT system and software matching was applied to measure the accuracy of the procedure. The angular deflection with the planned implant position was 0.40°. When comparing the 3D positions of the shoulder, there is a deviation of 0.72 mm resulting in an apical deviation of 0.72 mm. With the use of currently available technology, it is very well feasible to create in a virtual simulation a custom implant with congruent custom surgical tooling and to transfer this to a clinical setting. However, further research on multiple levels is needed to explore this novel approach. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
Marciano, David; Soize, Sébastien; Metaxas, Georgios; Portefaix, Christophe; Pierot, Laurent
2017-02-01
Data about non-invasive follow-up of aneurysm after stent-assisted coiling is scarce. We aimed to compare time-of-flight (TOF) magnetic resonance angiography (MRA) (3D-TOF-MRA) and contrast-enhanced MRA (CE-MRA) at 3-Tesla, with digital subtraction angiography (DSA) for evaluating aneurysm occlusion and parent artery patency after stent-assisted coiling. In this retrospective single-center study, patients were included if they had an intracranial aneurysm treated by stent-assisted coiling between March 2008 and June 2015, followed with both MRA sequences (3D-TOF-MRA and CE-MRA) at 3-Tesla and DSA, performed in an interval<48hours. Thirty-five aneurysms were included. Regarding aneurysm occlusion evaluation, agreement with DSA was better for CE-MRA (K=0.53) than 3D-TOF-MRA (K=0.28). Diagnostic accuracies for aneurysm remnant depiction were similar for 3D-TOF-MRA and CE-MRA (P=1). Both 3D-TOF-MRA (K=0.05) and CE-MRA (K=-0.04) were unable to detect pathological vessel compared to DSA, without difference in accuracy (P=0.68). For parent artery occlusion detection, agreement with DSA was substantial for 3D-TOF-MRA (K=0.64) and moderate for CE-MRA (K=0.45), with similar good diagnostic accuracies (P=1). After stent-assisted coiling treatment, 3D-TOF-MRA and CE-MRA demonstrated good accuracy to detect aneurysm remnant (but tended to overestimation). Although CE-MRA agreement with DSA was better, there was no statistical difference between 3D-TOF-MRA and CE-MRA accuracies. Both MRAs were unable to provide a precise evaluation of in-stent status but could detect parent vessel occlusion. Copyright © 2016 Elsevier Masson SAS. All rights reserved.
Höhn, K; Fuchs, J; Fröber, A; Kirmse, R; Glass, B; Anders-Össwein, M; Walther, P; Kräusslich, H-G; Dietrich, C
2015-08-01
In this study, we present a correlative microscopy workflow to combine detailed 3D fluorescence light microscopy data with ultrastructural information gained by 3D focused ion beam assisted scanning electron microscopy. The workflow is based on an optimized high pressure freezing/freeze substitution protocol that preserves good ultrastructural detail along with retaining the fluorescence signal in the resin embedded specimens. Consequently, cellular structures of interest can readily be identified and imaged by state of the art 3D confocal fluorescence microscopy and are precisely referenced with respect to an imprinted coordinate system on the surface of the resin block. This allows precise guidance of the focused ion beam assisted scanning electron microscopy and limits the volume to be imaged to the structure of interest. This, in turn, minimizes the total acquisition time necessary to conduct the time consuming ultrastructural scanning electron microscope imaging while eliminating the risk to miss parts of the target structure. We illustrate the value of this workflow for targeting virus compartments, which are formed in HIV-pulsed mature human dendritic cells. © 2015 The Authors Journal of Microscopy © 2015 Royal Microscopical Society.
FPCAS3D User's guide: A three dimensional full potential aeroelastic program, version 1
NASA Technical Reports Server (NTRS)
Bakhle, Milind A.
1995-01-01
The FPCAS3D computer code has been developed for aeroelastic stability analysis of bladed disks such as those in fans, compressors, turbines, propellers, or propfans. The aerodynamic analysis used in this code is based on the unsteady three-dimensional full potential equation which is solved for a blade row. The structural analysis is based on a finite-element model for each blade. Detailed explanations of the aerodynamic analysis, the numerical algorithms, and the aeroelastic analysis are not given in this report. This guide can be used to assist in the preparation of the input data required by the FPCAS3D code. A complete description of the input data is provided in this report. In addition, six examples, including inputs and outputs, are provided.
Zeng, Canjun; Xing, Weirong; Wu, Zhanglin; Huang, Huajun; Huang, Wenhua
2016-10-01
Treatment of acetabular fractures remains one of the most challenging tasks that orthopaedic surgeons face. An accurate assessment of the injuries and preoperative planning are essential for an excellent reduction. The purpose of this study was to evaluate the feasibility, accuracy and effectiveness of performing 3D printing technology and computer-assisted virtual surgical procedures for preoperative planning in acetabular fractures. We hypothesised that more accurate preoperative planning using 3D printing models will reduce the operation time and significantly improve the outcome of acetabular fracture repair. Ten patients with acetabular fractures were recruited prospectively and examined by CT scanning. A 3-D model of each acetabular fracture was reconstructed with MIMICS14.0 software from the DICOM file of the CT data. Bone fragments were moved and rotated to simulate fracture reduction and restore the pelvic integrity with virtual fixation. The computer-assisted 3D image of the reduced acetabula was printed for surgery simulation and plate pre-bending. The postoperative CT scan was performed to compare the consistency of the preoperative planning with the surgical implants by 3D-superimposition in MIMICS14.0, and evaluated by Matta's method. Computer-based pre-operations were precisely mimicked and consistent with the actual operations in all cases. The pre-bent fixation plates had an anatomical shape specifically fit to the individual pelvis without further bending or adjustment at the time of surgery and fracture reductions were significantly improved. Seven out of 10 patients had a displacement of fracture reduction of less than 1mm; 3 cases had a displacement of fracture reduction between 1 and 2mm. The 3D printing technology combined with virtual surgery for acetabular fractures is feasible, accurate, and effective leading to improved patient-specific preoperative planning and outcome of real surgery. The results provide useful technical tips in planning pelvic surgeries. Copyright © 2016 Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Zhao, Ruitu; Wang, Mu; Chen, Baojie; Liu, Ke; Pun, Edwin Yue-Bun; Lin, Hai
2011-04-01
Bent waveguide structures (S-, U-, and F-bend) based on buried Er3+/Yb3+ codoped phosphate glass waveguide channel fabricated by field-assisted annealing have been designed to achieve high-gain C-band integrated amplification. Using a simulated-bend method, the optimal radius for the curved structure is derived to be 0.90 cm with loss coefficient of 0.02 dB/cm, as the substrate size is schemed to be 4×3 cm2. In the wavelength range of 1520 to 1575 nm, obvious gain enhancement for the bent structure waveguides is anticipated, and for the F-bend waveguide, the internal gain at 1534-nm wavelength is derived to be 41.61 dB, which is much higher than the value of 26.22 and 13.81 dB in the U- and S-bend waveguides, respectively, and over three times higher than that of the straight one. The simulation results indicate that the bent structure design is beneficial in obtaining high signal gain in buried Er3+/Yb3+ codoped phosphate glass waveguides, which lays the foundation for further design and fabrication of integrated devices.
Li, Yongshen; Song, Yunna; Ma, Zheng; Niu, Shuai; Li, Jihui; Li, Ning
2018-06-01
In this article, phosphonic acid silver-graphene oxide nanomaterials (Nano-PAS-GO) was synthesized from silver nitrate (AgNO 3 ) solution and phosphoric graphene oxide (PGO) via the convenient ultrasonic-assisted method, and the structure and morphology were characterized, and the photocatalytic activity and recyclability were evaluated through photocatalyzing degradation of Rhodamin B (RhB) aqueous solution, and the possible photocatalytic mechanism was also discussed. Based on those, it was confirmed that Nano-PAS-GO has been synthesized from AgNO 3 solution and PGO colloidal suspension under ultrasonic-assisted condition, and Nano-PAS-GO has consisted of phosphoric acid silver nanoparticles and GO with 2D lattice (2D GO lattice) connected in the form of C-P bonds, and the photodegradation rate of Nano-PAS-GO for RhB aqueous solution has reached 93.99%, and Nano-PAS-GO has possessed the nicer recyclability when the photocatalytic time was 50 min. From those results, the strong and stable interface . between PAS nanoparticles and 2D GO lattice connected in the form of the covalent bonds has effectively inhibited the occurrence of the photocorrosion phenomenon. Copyright © 2018 Elsevier B.V. All rights reserved.
ERIC Educational Resources Information Center
San Mateo County Office of Education, Redwood City, CA. Career Preparation Centers.
This first of fifteen sets of Adult Competency Education (ACE) Based Job Descriptions in the ACE kit contains job descriptions for Child Care Attendent, Guard, and Medical Assistant. Each begins with a fact sheet that includes this information: occupational title, D.O.T. code, ACE number, career ladder, D.O.T. general educational developmental…
2D/3D facial feature extraction
NASA Astrophysics Data System (ADS)
Çinar Akakin, Hatice; Ali Salah, Albert; Akarun, Lale; Sankur, Bülent
2006-02-01
We propose and compare three different automatic landmarking methods for near-frontal faces. The face information is provided as 480x640 gray-level images in addition to the corresponding 3D scene depth information. All three methods follow a coarse-to-fine suite and use the 3D information in an assist role. The first method employs a combination of principal component analysis (PCA) and independent component analysis (ICA) features to analyze the Gabor feature set. The second method uses a subset of DCT coefficients for template-based matching. These two methods employ SVM classifiers with polynomial kernel functions. The third method uses a mixture of factor analyzers to learn Gabor filter outputs. We contrast the localization performance separately with 2D texture and 3D depth information. Although the 3D depth information per se does not perform as well as texture images in landmark localization, the 3D information has still a beneficial role in eliminating the background and the false alarms.
CH-47D Rotating System Fault Sensing for Condition Based Maintenance
2011-03-01
replacement. This research seeks to create an analytical model in the Rotorcraft Comprehensive Analysis System which will enable the identifica- tion of...answer my many questions. Without your assistance and that of Dr. Jon Keller and Mr. Clayton Kachelle at AMRDEC, the Rotorcraft Comprehensive Analysis...20 3.1 Overview . . . . . . . . . . . . . . . . . . . . . . . . . . 20 3.2 Rotorcraft Comprehensive Analysis
Wang, Tsung-Jen; Lin, Yu-Huang; Chang, David C-K; Chou, Hsiu-Chu; Wang, I-Jong
2012-04-01
To analyse the magnitude of cylindrical corrections over which cyclotorsion compensation with iris recognition (IR) technology is beneficial during wavefront laser-assisted in situ keratomileusis. A retrospectively comparative case series. Fifty-four eyes that underwent wavefront laser-assisted in situ keratomileusis without IR (non-IR group) and 53 eyes that underwent wavefront laser-assisted in situ keratomileusis with IR (IR group) were recruited. Subgroup analysis based on baseline astigmatism were: a low degree of astigmatism (≥1.00 D to <2.00 D), a moderate degree of astigmatism (≥2.00 D to <3.00 D) and a high degree of astigmatism (≥3.00 D). Vector and non-vector analyses were used for comparison. The mean cylinder was -1.89 ± 0.76 D in the non-IR group and -2.00 ± 0.77 D in the IR group. Postoperatively, 38 eyes (74.50%) in the IR group and 31 eyes (57.50%) in the non-IR group were within ± 0.50 D of the target induced astigmatism vector (P = 0.063). The difference vector was 0.49 ± 0.28 in the IR group and 0.63 ± 0.40 in the non-IR group (P = 0.031). In the analysis of subgroups, the magnitude of error was significantly lower in the moderate IR subgroup than that of the moderate non-IR subgroup (P = 0.034). Furthermore, the moderate IR subgroup had a lower mean difference vector (P = 0.0078) and a greater surgically induced astigmatism (P = 0.036) than those of the moderate non-IR group. Wavefront laser-assisted in situ keratomileusis for the treatment of astigmatism using IR technology was effective and accurate for the treatment of myopic astigmatism. © 2011 The Authors. Clinical and Experimental Ophthalmology © 2011 Royal Australian and New Zealand College of Ophthalmologists.
SPADAS: a high-speed 3D single-photon camera for advanced driver assistance systems
NASA Astrophysics Data System (ADS)
Bronzi, D.; Zou, Y.; Bellisai, S.; Villa, F.; Tisa, S.; Tosi, A.; Zappa, F.
2015-02-01
Advanced Driver Assistance Systems (ADAS) are the most advanced technologies to fight road accidents. Within ADAS, an important role is played by radar- and lidar-based sensors, which are mostly employed for collision avoidance and adaptive cruise control. Nonetheless, they have a narrow field-of-view and a limited ability to detect and differentiate objects. Standard camera-based technologies (e.g. stereovision) could balance these weaknesses, but they are currently not able to fulfill all automotive requirements (distance range, accuracy, acquisition speed, and frame-rate). To this purpose, we developed an automotive-oriented CMOS single-photon camera for optical 3D ranging based on indirect time-of-flight (iTOF) measurements. Imagers based on Single-photon avalanche diode (SPAD) arrays offer higher sensitivity with respect to CCD/CMOS rangefinders, have inherent better time resolution, higher accuracy and better linearity. Moreover, iTOF requires neither high bandwidth electronics nor short-pulsed lasers, hence allowing the development of cost-effective systems. The CMOS SPAD sensor is based on 64 × 32 pixels, each able to process both 2D intensity-data and 3D depth-ranging information, with background suppression. Pixel-level memories allow fully parallel imaging and prevents motion artefacts (skew, wobble, motion blur) and partial exposure effects, which otherwise would hinder the detection of fast moving objects. The camera is housed in an aluminum case supporting a 12 mm F/1.4 C-mount imaging lens, with a 40°×20° field-of-view. The whole system is very rugged and compact and a perfect solution for vehicle's cockpit, with dimensions of 80 mm × 45 mm × 70 mm, and less that 1 W consumption. To provide the required optical power (1.5 W, eye safe) and to allow fast (up to 25 MHz) modulation of the active illumination, we developed a modular laser source, based on five laser driver cards, with three 808 nm lasers each. We present the full characterization of the 3D automotive system, operated both at night and during daytime, in both indoor and outdoor, in real traffic, scenario. The achieved long-range (up to 45m), high dynamic-range (118 dB), highspeed (over 200 fps) 3D depth measurement, and high precision (better than 90 cm at 45 m), highlight the excellent performance of this CMOS SPAD camera for automotive applications.
Ross, James D.; Cullen, D. Kacy; Harris, James P.; LaPlaca, Michelle C.; DeWeerth, Stephen P.
2015-01-01
Three-dimensional (3-D) image analysis techniques provide a powerful means to rapidly and accurately assess complex morphological and functional interactions between neural cells. Current software-based identification methods of neural cells generally fall into two applications: (1) segmentation of cell nuclei in high-density constructs or (2) tracing of cell neurites in single cell investigations. We have developed novel methodologies to permit the systematic identification of populations of neuronal somata possessing rich morphological detail and dense neurite arborization throughout thick tissue or 3-D in vitro constructs. The image analysis incorporates several novel automated features for the discrimination of neurites and somata by initially classifying features in 2-D and merging these classifications into 3-D objects; the 3-D reconstructions automatically identify and adjust for over and under segmentation errors. Additionally, the platform provides for software-assisted error corrections to further minimize error. These features attain very accurate cell boundary identifications to handle a wide range of morphological complexities. We validated these tools using confocal z-stacks from thick 3-D neural constructs where neuronal somata had varying degrees of neurite arborization and complexity, achieving an accuracy of ≥95%. We demonstrated the robustness of these algorithms in a more complex arena through the automated segmentation of neural cells in ex vivo brain slices. These novel methods surpass previous techniques by improving the robustness and accuracy by: (1) the ability to process neurites and somata, (2) bidirectional segmentation correction, and (3) validation via software-assisted user input. This 3-D image analysis platform provides valuable tools for the unbiased analysis of neural tissue or tissue surrogates within a 3-D context, appropriate for the study of multi-dimensional cell-cell and cell-extracellular matrix interactions. PMID:26257609
Knowledge-Based Object Detection in Laser Scanning Point Clouds
NASA Astrophysics Data System (ADS)
Boochs, F.; Karmacharya, A.; Marbs, A.
2012-07-01
Object identification and object processing in 3D point clouds have always posed challenges in terms of effectiveness and efficiency. In practice, this process is highly dependent on human interpretation of the scene represented by the point cloud data, as well as the set of modeling tools available for use. Such modeling algorithms are data-driven and concentrate on specific features of the objects, being accessible to numerical models. We present an approach that brings the human expert knowledge about the scene, the objects inside, and their representation by the data and the behavior of algorithms to the machine. This "understanding" enables the machine to assist human interpretation of the scene inside the point cloud. Furthermore, it allows the machine to understand possibilities and limitations of algorithms and to take this into account within the processing chain. This not only assists the researchers in defining optimal processing steps, but also provides suggestions when certain changes or new details emerge from the point cloud. Our approach benefits from the advancement in knowledge technologies within the Semantic Web framework. This advancement has provided a strong base for applications based on knowledge management. In the article we will present and describe the knowledge technologies used for our approach such as Web Ontology Language (OWL), used for formulating the knowledge base and the Semantic Web Rule Language (SWRL) with 3D processing and topologic built-ins, aiming to combine geometrical analysis of 3D point clouds, and specialists' knowledge of the scene and algorithmic processing.
Wang, Jing; Qi, Minghao; Xuan, Yi; Huang, Haiyang; Li, You; Li, Ming; Chen, Xin; Jia, Qi; Sheng, Zhen; Wu, Aimin; Li, Wei; Wang, Xi; Zou, Shichang; Gan, Fuwan
2014-01-01
A novel silicon-on-insulator (SOI) polarization splitter-rotator (PSR) with a large fabrication tolerance is proposed based on cascaded multimode interference (MMI) couplers and an assisted mode-evolution taper. The tapers are designed to adiabatically convert the input TM0 mode into the TE1 mode, which will output as the TE0 mode after processed by the subsequent MMI mode converter, 90-degree phase shifter (PS) and MMI 3 dB coupler. The numerical simulation results show that the proposed device has a < 0.5 dB insertion loss with < −17 dB crosstalk in C optical communication band. Fabrication tolerance analysis is also performed with respect to the deviations of MMI coupler width, PS width, slab height and upper-cladding refractive index, showing that this device could work well even when affected by considerable fabrication errors. With such a robust performance with a large bandwidth, this device offers potential applications for CMOS-compatible polarization diversity, especially in the booming 100 Gb/s coherent optical communications based on silicon photonics technology. PMID:25402029
Wang, Jing; Qi, Minghao; Xuan, Yi; Huang, Haiyang; Li, You; Li, Ming; Chen, Xin; Jia, Qi; Sheng, Zhen; Wu, Aimin; Li, Wei; Wang, Xi; Zou, Shichang; Gan, Fuwan
2014-11-17
A novel silicon-on-insulator (SOI) polarization splitter-rotator (PSR) with a large fabrication tolerance is proposed based on cascaded multimode interference (MMI) couplers and an assisted mode-evolution taper. The tapers are designed to adiabatically convert the input TM(0) mode into the TE(1) mode, which will output as the TE(0) mode after processed by the subsequent MMI mode converter, 90-degree phase shifter (PS) and MMI 3 dB coupler. The numerical simulation results show that the proposed device has a < 0.5 dB insertion loss with < -17 dB crosstalk in C optical communication band. Fabrication tolerance analysis is also performed with respect to the deviations of MMI coupler width, PS width, slab height and upper-cladding refractive index, showing that this device could work well even when affected by considerable fabrication errors. With such a robust performance with a large bandwidth, this device offers potential applications for CMOS-compatible polarization diversity, especially in the booming 100 Gb/s coherent optical communications based on silicon photonics technology.
KleinJan, Gijs H; van den Berg, Nynke S; Brouwer, Oscar R; de Jong, Jeroen; Acar, Cenk; Wit, Esther M; Vegt, Erik; van der Noort, Vincent; Valdés Olmos, Renato A; van Leeuwen, Fijs W B; van der Poel, Henk G
2014-12-01
The hybrid tracer was introduced to complement intraoperative radiotracing towards the sentinel nodes (SNs) with fluorescence guidance. Improve in vivo fluorescence-based SN identification for prostate cancer by optimising hybrid tracer preparation, injection technique, and fluorescence imaging hardware. Forty patients with a Briganti nomogram-based risk >10% of lymph node (LN) metastases were included. After intraprostatic tracer injection, SN mapping was performed (lymphoscintigraphy and single-photon emission computed tomography with computed tomography (SPECT-CT)). In groups 1 and 2, SNs were pursued intraoperatively using a laparoscopic gamma probe followed by fluorescence imaging (FI). In group 3, SNs were initially located via FI. Compared with group 1, in groups 2 and 3, a new tracer formulation was introduced that had a reduced total injected volume (2.0 ml vs. 3.2 ml) but increased particle concentration. For groups 1 and 2, the Tricam SLII with D-Light C laparoscopic FI (LFI) system was used. In group 3, the LFI system was upgraded to an Image 1 HUB HD with D-Light P system. Hybrid tracer-based SN biopsy, extended pelvic lymph node dissection, and robot-assisted radical prostatectomy. Number and location of the preoperatively identified SNs, in vivo fluorescence-based SN identification rate, tumour status of SNs and LNs, postoperative complications, and biochemical recurrence (BCR). Mean fluorescence-based SN identification improved from 63.7% (group 1) to 85.2% and 93.5% for groups 2 and 3, respectively (p=0.012). No differences in postoperative complications were found. BCR occurred in three pN0 patients. Stepwise optimisation of the hybrid tracer formulation and the LFI system led to a significant improvement in fluorescence-assisted SN identification. Preoperative SPECT-CT remained essential for guiding intraoperative SN localisation. Intraoperative fluorescence-based SN visualisation can be improved by enhancing the hybrid tracer formulation and laparoscopic fluorescence imaging system. Copyright © 2014 European Association of Urology. Published by Elsevier B.V. All rights reserved.
NASA Astrophysics Data System (ADS)
Sierra, Heidy; Brooks, Dana; Dimarzio, Charles
2010-07-01
The extraction of 3-D morphological information about thick objects is explored in this work. We extract this information from 3-D differential interference contrast (DIC) images by applying a texture detection method. Texture extraction methods have been successfully used in different applications to study biological samples. A 3-D texture image is obtained by applying a local entropy-based texture extraction method. The use of this method to detect regions of blastocyst mouse embryos that are used in assisted reproduction techniques such as in vitro fertilization is presented as an example. Results demonstrate the potential of using texture detection methods to improve morphological analysis of thick samples, which is relevant to many biomedical and biological studies. Fluorescence and optical quadrature microscope phase images are used for validation.
Automated detection and segmentation of follicles in 3D ultrasound for assisted reproduction
NASA Astrophysics Data System (ADS)
Narayan, Nikhil S.; Sivanandan, Srinivasan; Kudavelly, Srinivas; Patwardhan, Kedar A.; Ramaraju, G. A.
2018-02-01
Follicle quantification refers to the computation of the number and size of follicles in 3D ultrasound volumes of the ovary. This is one of the key factors in determining hormonal dosage during female infertility treatments. In this paper, we propose an automated algorithm to detect and segment follicles in 3D ultrasound volumes of the ovary for quantification. In a first of its kind attempt, we employ noise-robust phase symmetry feature maps as likelihood function to perform mean-shift based follicle center detection. Max-flow algorithm is used for segmentation and gray weighted distance transform is employed for post-processing the results. We have obtained state-of-the-art results with a true positive detection rate of >90% on 26 3D volumes with 323 follicles.
A streaming-based solution for remote visualization of 3D graphics on mobile devices.
Lamberti, Fabrizio; Sanna, Andrea
2007-01-01
Mobile devices such as Personal Digital Assistants, Tablet PCs, and cellular phones have greatly enhanced user capability to connect to remote resources. Although a large set of applications are now available bridging the gap between desktop and mobile devices, visualization of complex 3D models is still a task hard to accomplish without specialized hardware. This paper proposes a system where a cluster of PCs, equipped with accelerated graphics cards managed by the Chromium software, is able to handle remote visualization sessions based on MPEG video streaming involving complex 3D models. The proposed framework allows mobile devices such as smart phones, Personal Digital Assistants (PDAs), and Tablet PCs to visualize objects consisting of millions of textured polygons and voxels at a frame rate of 30 fps or more depending on hardware resources at the server side and on multimedia capabilities at the client side. The server is able to concurrently manage multiple clients computing a video stream for each one; resolution and quality of each stream is tailored according to screen resolution and bandwidth of the client. The paper investigates in depth issues related to latency time, bit rate and quality of the generated stream, screen resolutions, as well as frames per second displayed.
Schwein, Adeline; Kramer, Benjamin; Chinnadurai, Ponraj; Virmani, Neha; Walker, Sean; O'Malley, Marcia; Lumsden, Alan B; Bismuth, Jean
2018-04-01
Combining three-dimensional (3D) catheter control with electromagnetic (EM) tracking-based navigation significantly reduced fluoroscopy time and improved robotic catheter movement quality in a previous in vitro pilot study. The aim of this study was to expound on previous results and to expand the value of EM tracking with a novel feature, assistednavigation, allowing automatic catheter orientation and semiautomatic vessel cannulation. Eighteen users navigated a robotic catheter in an aortic aneurysm phantom using an EM guidewire and a modified 9F robotic catheter with EM sensors at the tip of both leader and sheath. All users cannulated two targets, the left renal artery and posterior gate, using four visualization modes: (1) Standard fluoroscopy (control). (2) 2D biplane fluoroscopy showing real-time virtual catheter localization and orientation from EM tracking. (3) 2D biplane fluoroscopy with novel EM assisted navigation allowing the user to define the target vessel. The robotic catheter orients itself automatically toward the target; the user then only needs to advance the guidewire following this predefined optimized path to catheterize the vessel. Then, while advancing the catheter over the wire, the assisted navigation automatically modifies catheter bending and rotation in order to ensure smooth progression, avoiding loss of wire access. (4) Virtual 3D representation of the phantom showing real-time virtual catheter localization and orientation. Standard fluoroscopy was always available; cannulation and fluoroscopy times were noted for every mode and target cannulation. Quality of catheter movement was assessed by measuring the number of submovements of the catheter using the 3D coordinates of the EM sensors. A t-test was used to compare the standard fluoroscopy mode against EM tracking modes. EM tracking significantly reduced the mean fluoroscopy time (P < .001) and the number of submovements (P < .02) for both cannulation tasks. For the posterior gate, mean cannulation time was also significantly reduced when using EM tracking (P < .001). The use of novel EM assisted navigation feature (mode 3) showed further reduced cannulation time for the posterior gate (P = .002) and improved quality of catheter movement for the left renal artery cannulation (P = .021). These results confirmed the findings of a prior study that highlighted the value of combining 3D robotic catheter control and 3D navigation to improve safety and efficiency of endovascular procedures. The novel EM assisted navigation feature augments the robotic master/slave concept with automated catheter orientation toward the target and shows promising results in reducing procedure time and improving catheter motion quality. Copyright © 2017 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.
Wang, H; Wang, J J; Jiang, Y L; Tian, S Q; Ji, Z; Guo, F X; Sun, H T; Fan, J H; Xu, Y P
2016-12-20
Objective: To analyze the difference of dosimetric parameters between pre-plan and post-plan of 125 I radioactive seed implantation assisted by 3D printing individual non-coplanar template (3D printing template) for locally recurrent rectal cancer (LRRC). Methods: From February 2016 to April 2016, a total of 10 patients with locally recurrent rectal cancer received 125 I seeds implantation under CT guidance assisted by 3D printing template in Department of Radiation Oncology, Peking University Third Hospital.Each patient underwent CT simulation, three-dimentional treatment planning pre-implantation, 3D printing template design, radioactive seed implantation assisted by 3D printing template and dosimetric verification post implantation. The median activity of seed was 0.63 mCi (0.58 to 0.7 mCi) (2.15- 2.59×10 7 Bq), and the median number of seeds was 80 (19 to 192). D 90 , D 100 , V 100 , V 150 , CI, EI, HI, D 5cc , D 2cc of bladder and bowel of pre-plan and post-plan were calculated, respectively.Paired t test was used to evaluate the difference of dosimetric parameters between pre-plan and post-plan. Results: The median D 90 of pre-plan and post-plan were 13 761.0 and 12 798.8 cGy, respectively.The median D 100 of pre-plan and post-plan were 5 293.6 and 5 397.9 cGy, respectively.The median V 100 of pre-plan and post-plan were 90.0% and 90.0%, respectively.The median V 150 of pre-plan and post-plan were 63.8% and 62.4%, respectively.The median CI of pre-plan and post-plan were 0.73 and 0.67.The median EI of pre-plan and post-plan were 0.22 and 0.30, respectively. The median HI of pre-plan and post-plan were 0.29 and 0.31.The median bladder D 2cc of pre-plan and post-plan were 3 088.8 and 4 240.4 cGy, respectively.The median bowel D 2cc of pre-plan and post-plan were 7 051.6 and 7 903.9 cGy, respectively. Conclusions: 3D printing template might be helpful for locally recurrent rectal cancer patients who received 125 I radioactive seed implantation assisted by 3D printing individual template.Seed implantation might have more chances to achieve prescription dose and dose limitation of organs at risk of pre-plan, which is important for precise implantation and quality control.
Capillary-Force-Assisted Clean-Stamp Transfer of Two-Dimensional Materials.
Ma, Xuezhi; Liu, Qiushi; Xu, Da; Zhu, Yangzhi; Kim, Sanggon; Cui, Yongtao; Zhong, Lanlan; Liu, Ming
2017-11-08
A simple and clean method of transferring two-dimensional (2D) materials plays a critical role in the fabrication of 2D electronics, particularly the heterostructure devices based on the artificial vertical stacking of various 2D crystals. Currently, clean transfer techniques rely on sacrificial layers or bulky crystal flakes (e.g., hexagonal boron nitride) to pick up the 2D materials. Here, we develop a capillary-force-assisted clean-stamp technique that uses a thin layer of evaporative liquid (e.g., water) as an instant glue to increase the adhesion energy between 2D crystals and polydimethylsiloxane (PDMS) for the pick-up step. After the liquid evaporates, the adhesion energy decreases, and the 2D crystal can be released. The thin liquid layer is condensed to the PDMS surface from its vapor phase, which ensures the low contamination level on the 2D materials and largely remains their chemical and electrical properties. Using this method, we prepared graphene-based transistors with low charge-neutral concentration (3 × 10 10 cm -2 ) and high carrier mobility (up to 48 820 cm 2 V -1 s -1 at room temperature) and heterostructure optoelectronics with high operation speed. Finally, a capillary-force model is developed to explain the experiment.
Zhang, Dongxia; Gan, Yangzhou; Xiong, Jing; Xia, Zeyang
2017-02-01
Complete three-dimensional(3D) tooth model provides essential information to assist orthodontists for diagnosis and treatment planning. Currently, 3D tooth model is mainly obtained by segmentation and reconstruction from dental computed tomography(CT) images. However, the accuracy of 3D tooth model reconstructed from dental CT images is low and not applicable for invisalign design. And another serious problem also occurs, i.e. frequentative dental CT scan during different intervals of orthodontic treatment often leads to radiation to the patients. Hence, this paper proposed a method to reconstruct tooth model based on fusion of dental CT images and laser-scanned images. A complete3 D tooth model was reconstructed with the registration and fusion between the root reconstructed from dental CT images and the crown reconstructed from laser-scanned images. The crown of the complete 3D tooth model reconstructed with the proposed method has higher accuracy. Moreover, in order to reconstruct complete 3D tooth model of each orthodontic treatment interval, only one pre-treatment CT scan is needed and in the orthodontic treatment process only the laser-scan is required. Therefore, radiation to the patients can be reduced significantly.
Schooley, Benjamin; San Nicolas-Rocca, Tonia; Burkhard, Richard
2015-01-12
Many studies have provided evidence of the importance of quality provider-patient communications and have suggested improvements to patient understanding by using video-based instruction. The objective of this study was to understand how mobile information technology assisted video and three-dimensional (3D) image instruction, provided by a health care worker, influences two categories of outcome: (1) patient understanding of information about their condition and detailed medical discharge instructions; and (2) patient perceptions and attitudes toward their health care providers, which included physicians, nurses, and staff. We hypothesize that video and 3D image instruction, provided on a mobile, tablet hardware platform, will improve patient understanding about the diagnostic testing, diagnoses, procedures, medications, and health topics provided to them. We also propose that use of the tablet/video combination will result in improved attitudinal evaluation by patients of their providers and the treatment plan. This study evaluated a hospital clinic-based trial (patient N=284) of video and 3D image instruction, provided on a mobile, tablet hardware platform, and its potential to improve patient understanding about the diagnostic testing, diagnoses, procedures, medications, and health topics provided to them. Results showed strong evidence that the system was perceived as helpful for improving patient understanding, and that it improved communication between physicians and patients (P<.001). The advanced age of some patients had no effect on their perceptions of the tablet-based mediation. Physician comments provided useful insights on effective use of such systems in the future. Implications for further development and future research are discussed. This study added to the body of evidence that computer-assisted video instructional systems for patients can improve patient understanding of medical instructions from their health care providers and assist with patient compliance. In addition, such systems can be appealing to both patient and provider.
Schooley, Benjamin; San Nicolas-Rocca, Tonia
2015-01-01
Background Many studies have provided evidence of the importance of quality provider-patient communications and have suggested improvements to patient understanding by using video-based instruction. Objective The objective of this study was to understand how mobile information technology assisted video and three-dimensional (3D) image instruction, provided by a health care worker, influences two categories of outcome: (1) patient understanding of information about their condition and detailed medical discharge instructions; and (2) patient perceptions and attitudes toward their health care providers, which included physicians, nurses, and staff. We hypothesize that video and 3D image instruction, provided on a mobile, tablet hardware platform, will improve patient understanding about the diagnostic testing, diagnoses, procedures, medications, and health topics provided to them. We also propose that use of the tablet/video combination will result in improved attitudinal evaluation by patients of their providers and the treatment plan. Methods This study evaluated a hospital clinic-based trial (patient N=284) of video and 3D image instruction, provided on a mobile, tablet hardware platform, and its potential to improve patient understanding about the diagnostic testing, diagnoses, procedures, medications, and health topics provided to them. Results Results showed strong evidence that the system was perceived as helpful for improving patient understanding, and that it improved communication between physicians and patients (P<.001). The advanced age of some patients had no effect on their perceptions of the tablet-based mediation. Physician comments provided useful insights on effective use of such systems in the future. Implications for further development and future research are discussed. Conclusions This study added to the body of evidence that computer-assisted video instructional systems for patients can improve patient understanding of medical instructions from their health care providers and assist with patient compliance. In addition, such systems can be appealing to both patient and provider. PMID:25583145
Learner Autonomy in a Task-Based 3D World and Production
ERIC Educational Resources Information Center
Collentine, Karina
2011-01-01
This study contributes to the research on learner autonomy by examining the relationship between Little's (1991) notions of "independent action" and "decision-making", input, and L2 production in computer-assisted language learning (CALL). Operationalizing "independent action" and "decision-making" with Dam's (1995) definition that focuses on…
Zhao, Li; Dong, Biliang; Li, Shaozhou; Zhou, Lijun; Lai, Linfei; Wang, Zhiwei; Zhao, Shulin; Han, Min; Gao, Kai; Lu, Min; Xie, Xiaoji; Chen, Bo; Liu, Zhengdong; Wang, Xiangjing; Zhang, Hao; Li, Hai; Liu, Juqing; Zhang, Hua; Huang, Xiao; Huang, Wei
2017-06-27
Two-dimensional (2D) metal-organic framework (MOF) nanosheets have been recently regarded as the model electrocatalysts due to their porous structure, fast mass and ion transfer through the thickness, and large portion of exposed active metal centers. Combining them with electrically conductive 2D nanosheets is anticipated to achieve further improved performance in electrocatalysis. In this work, we in situ hybridized 2D cobalt 1,4-benzenedicarboxylate (CoBDC) with Ti 3 C 2 T x (the MXene phase) nanosheets via an interdiffusion reaction-assisted process. The resulting hybrid material was applied in the oxygen evolution reaction and achieved a current density of 10 mA cm -2 at a potential of 1.64 V vs reversible hydrogen electrode and a Tafel slope of 48.2 mV dec -1 in 0.1 M KOH. These results outperform those obtained by the standard IrO 2 -based catalyst and are comparable with or even better than those achieved by the previously reported state-of-the-art transition-metal-based catalysts. While the CoBDC layer provided the highly porous structure and large active surface area, the electrically conductive and hydrophilic Ti 3 C 2 T x nanosheets enabled the rapid charge and ion transfer across the well-defined Ti 3 C 2 T x -CoBDC interface and facilitated the access of aqueous electrolyte to the catalytically active CoBDC surfaces. The hybrid nanosheets were further fabricated into an air cathode for a rechargeable zinc-air battery, which was successfully used to power a light-emitting diode. We believe that the in situ hybridization of MXenes and 2D MOFs with interface control will provide more opportunities for their use in energy-based applications.
Recent development on computer aided tissue engineering--a review.
Sun, Wei; Lal, Pallavi
2002-02-01
The utilization of computer-aided technologies in tissue engineering has evolved in the development of a new field of computer-aided tissue engineering (CATE). This article reviews recent development and application of enabling computer technology, imaging technology, computer-aided design and computer-aided manufacturing (CAD and CAM), and rapid prototyping (RP) technology in tissue engineering, particularly, in computer-aided tissue anatomical modeling, three-dimensional (3-D) anatomy visualization and 3-D reconstruction, CAD-based anatomical modeling, computer-aided tissue classification, computer-aided tissue implantation and prototype modeling assisted surgical planning and reconstruction.
NASA Astrophysics Data System (ADS)
Imayoshi, Takahiro; Oigawa, Haruhiro; Shigekawa, Hidemi; Tokumoto, Hiroshi
2003-08-01
Under the controlled As partial pressure, the nitridation process of GaAs(0 0 1)-(2 × 4) surface was studied using a scanning tunneling microscope (STM) combined with an electron cyclotron resonance plasma-assisted molecular beam epitaxy system. With either prolonging the nitridation time or decreasing the As partial pressure, the previously reported (3 × 3) structure with two dimers per surface cell ((3 × 3)-2D) was found to progressively convert into a new (3 × 3) structure characterized by one dimer per surface cell ((3 × 3)-1D). Reversely the exposure to arsenic transformed the structure from (3 × 3)-1D to (3 × 3)-2D, suggesting that the topmost layer is composed of As 2-dimers. Based on these STM images together with the X-ray photoelectron spectroscopy data, we propose the new As 2-dimer coverage models to explain both (3 × 3)-1D and -2D structures involving the exchange reaction of arsenic with nitrogen in the subsurface region of GaAs.
3D surface-based registration of ultrasound and histology in prostate cancer imaging.
Schalk, Stefan G; Postema, Arnoud; Saidov, Tamerlan A; Demi, Libertario; Smeenge, Martijn; de la Rosette, Jean J M C H; Wijkstra, Hessel; Mischi, Massimo
2016-01-01
Several transrectal ultrasound (TRUS)-based techniques aiming at accurate localization of prostate cancer are emerging to improve diagnostics or to assist with focal therapy. However, precise validation prior to introduction into clinical practice is required. Histopathology after radical prostatectomy provides an excellent ground truth, but needs accurate registration with imaging. In this work, a 3D, surface-based, elastic registration method was developed to fuse TRUS images with histopathologic results. To maximize the applicability in clinical practice, no auxiliary sensors or dedicated hardware were used for the registration. The mean registration errors, measured in vitro and in vivo, were 1.5±0.2 and 2.1±0.5mm, respectively. Copyright © 2015 Elsevier Ltd. All rights reserved.
Vlachopoulos, Lazaros; Schweizer, Andreas; Meyer, Dominik C; Gerber, Christian; Fürnstahl, Philipp
2017-08-01
The surgical treatment of malunions after midshaft clavicle fractures is associated with a number of potential complications and the surgical procedure is challenging. However, with appropriate and meticulous preoperative surgical planning, the surgical correction yields satisfactory results. The purpose of this study was to provide a guideline and detailed overview for the computer-assisted planning and 3-dimensional (3D) correction of malunions of the clavicle. The 3D bone surface models of the pathologic and contralateral sides were created on the basis of computed tomography data. The computer-assisted assessment of the deformity, the preoperative plan, and the design of patient-specific guides enabling compression plating are described. We demonstrate the benefit and versatility of computer-assisted planning for corrective osteotomies of malunions of the midshaft clavicle. In combination with patient-specific guides and compression plating technique, the correction can be performed in a more standardized fashion. We describe the determination of the contact-optimized osteotomy plane. An osteotomy along this plane facilitates the correction and enlarges the contact between the fragments at once. We further developed a technique of a stepped osteotomy that is based on the calculation of the contact-optimized osteotomy plane. The stepped osteotomy enables the length to be restored without the need of structural bone graft. The application of the stepped osteotomy is presented for malunions of the clavicle with shortening and excessive callus formation. The 3D preoperative planning and patient-specific guides for corrective osteotomies of the clavicle may help reduce the number of potential complications and yield results that are more predictable. Copyright © 2017 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.
Tsauo, Jiaywei; Luo, Xuefeng; Ye, Linchao; Li, Xiao
2015-06-01
This study was designed to report our results with a modified technique of three-dimensional (3D) path planning software assisted transjugular intrahepatic portosystemic shunt (TIPS). 3D path planning software was recently developed to facilitate TIPS creation by using two carbon dioxide portograms acquired at least 20° apart to generate a 3D path for overlay needle guidance. However, one shortcoming is that puncturing along the overlay would be technically impossible if the angle of the liver access set and the angle of the 3D path are not the same. To solve this problem, a prototype 3D path planning software was fitted with a utility to calculate the angle of the 3D path. Using this, we modified the angle of the liver access set accordingly during the procedure in ten patients. Failure for technical reasons occurred in three patients (unsuccessful wedged hepatic venography in two cases, software technical failure in one case). The procedure was successful in the remaining seven patients, and only one needle pass was required to obtain portal vein access in each case. The course of puncture was comparable to the 3D path in all patients. No procedure-related complication occurred following the procedures. Adjusting the angle of the liver access set to match the angle of the 3D path determined by the software appears to be a favorable modification to the technique of 3D path planning software assisted TIPS.
Yao, William C; Regone, Rachel M; Huyhn, Nancy; Butler, E Brian; Takashima, Masayoshi
2014-03-01
Develop a novel three-dimensional (3-D) anatomical model to assist in improving spatial knowledge of the skull base, paranasal sinuses, and adjacent structures, and validate the utilization of 3-D reconstruction to augment two-dimensional (2-D) computed tomography (CT) for the training of medical students and otolaryngology-head and neck surgery residents. Prospective study. A study of 18 subjects studying sinus anatomy was conducted at a tertiary academic center during the 2011 to 2012 academic year. An image processing and 3-D modeling program was used to create a color coded 3-D scalable/layerable/rotatable model of key paranasal and skull base structures from a 2-D high-resolution sinus CT scan. Subjects received instruction of the sinus anatomy in two sessions, first through review of a 2-D CT sinus scan, followed by an educational module of the 3-D reconstruction. After each session, subjects rated their knowledge of the sinus and adjacent structures on a self-assessment questionnaire. Significant improvement in the perceived understanding of the anatomy was noted after the 3-D educational module session when compared to the 2-D CT session alone (P < .01). Every subject believed the addition of 3-D imaging accelerated their education of sinus anatomy and recommended its use to others. The impression of the learners was that a 3-D educational module, highlighting key structures, is a highly effective tool to enhance the education of medical students and otolaryngology residents in sinus and skull base anatomy and its adjacent structures, specifically in conceptualizing the spatial orientation of these structures. © 2013 The American Laryngological, Rhinological and Otological Society, Inc.
CT-based manual segmentation and evaluation of paranasal sinuses.
Pirner, S; Tingelhoff, K; Wagner, I; Westphal, R; Rilk, M; Wahl, F M; Bootz, F; Eichhorn, Klaus W G
2009-04-01
Manual segmentation of computed tomography (CT) datasets was performed for robot-assisted endoscope movement during functional endoscopic sinus surgery (FESS). Segmented 3D models are needed for the robots' workspace definition. A total of 50 preselected CT datasets were each segmented in 150-200 coronal slices with 24 landmarks being set. Three different colors for segmentation represent diverse risk areas. Extension and volumetric measurements were performed. Three-dimensional reconstruction was generated after segmentation. Manual segmentation took 8-10 h for each CT dataset. The mean volumes were: right maxillary sinus 17.4 cm(3), left side 17.9 cm(3), right frontal sinus 4.2 cm(3), left side 4.0 cm(3), total frontal sinuses 7.9 cm(3), sphenoid sinus right side 5.3 cm(3), left side 5.5 cm(3), total sphenoid sinus volume 11.2 cm(3). Our manually segmented 3D-models present the patient's individual anatomy with a special focus on structures in danger according to the diverse colored risk areas. For safe robot assistance, the high-accuracy models represent an average of the population for anatomical variations, extension and volumetric measurements. They can be used as a database for automatic model-based segmentation. None of the segmentation methods so far described provide risk segmentation. The robot's maximum distance to the segmented border can be adjusted according to the differently colored areas.
NASA Astrophysics Data System (ADS)
Sadeghi Neshat, Hamid; Bax, Jeffery; Barker, Kevin; Gardi, Lori; Chedalavada, Jason; Kakani, Nirmal; Fenster, Aaron
2014-03-01
Image-guided percutaneous ablation is the standard treatment for focal liver tumors deemed inoperable and is commonly used to maintain eligibility for patients on transplant waitlists. Radiofrequency (RFA), microwave (MWA) and cryoablation technologies are all delivered via one or a number of needle-shaped probes inserted directly into the tumor. Planning is mostly based on contrast CT/MRI. While intra-procedural CT is commonly used to confirm the intended probe placement, 2D ultrasound (US) remains the main, and in some centers the only imaging modality used for needle guidance. Corresponding intraoperative 2D US with planning and other intra-procedural imaging modalities is essential for accurate needle placement. However, identification of matching features of interest among these images is often challenging given the limited field-of-view (FOV) and low quality of 2D US images. We have developed a passive tracking arm with a motorized scan-head and software tools to improve guiding capabilities of conventional US by large FOV 3D US scans that provides more anatomical landmarks that can facilitate registration of US with both planning and intra-procedural images. The tracker arm is used to scan the whole liver with a high geometrical accuracy that facilitates multi-modality landmark based image registration. Software tools are provided to assist with the segmentation of the ablation probes and tumors, find the 2D view that best shows the probe(s) from a 3D US image, and to identify the corresponding image from planning CT scans. In this paper, evaluation results from laboratory testing and a phase 1 clinical trial for planning and guiding RFA and MWA procedures using the developed system will be presented. Early clinical results show a comparable performance to intra-procedural CT that suggests 3D US as a cost-effective alternative with no side-effects in centers where CT is not available.
3D printing strategies for peripheral nerve regeneration.
Petcu, Eugen B; Midha, Rajiv; McColl, Erin; Popa-Wagner, Aurel; Chirila, Traian V; Dalton, Paul D
2018-03-23
After many decades of biomaterials research for peripheral nerve regeneration, a clinical product (the nerve guide), is emerging as a proven alternative for relatively short injury gaps. This review identifies aspects where 3D printing can assist in improving long-distance nerve guide regeneration strategies. These include (1) 3D printing of the customizable nerve guides, (2) fabrication of scaffolds that fill nerve guides, (3) 3D bioprinting of cells within a matrix/bioink into the nerve guide lumen and the (4) establishment of growth factor gradients along the length a nerve guide. The improving resolution of 3D printing technologies will be an important factor for peripheral nerve regeneration, as fascicular-like guiding structures provide one path to improved nerve guidance. The capability of 3D printing to manufacture complex structures from patient data based on existing medical imaging technologies is an exciting aspect that could eventually be applied to treating peripheral nerve injury. Ultimately, the goal of 3D printing in peripheral nerve regeneration is the automated fabrication, potentially customized for the patient, of structures within the nerve guide that significantly outperform the nerve autograft over large gap injuries.
Wang, Dongwen; Zhang, Bin; Yuan, Xiaobin; Zhang, Xuhui; Liu, Chen
2015-09-01
To evaluate the feasibility and effectiveness of preoperative planning and real-time assisted surgical navigation for three-dimensional laparoscopic partial nephrectomy under the guidance of three-dimensional individual digital model (3D-IDM) created using three-dimensional medical image reconstructing and guiding system (3D-MIRGS). Between May 2012 and February 2014, 44 patients with cT1 renal tumors underwent retroperitoneal laparoscopic partial nephrectomy (LPN) using a three-dimensional laparoscopic system. The 3D-IDMs were created using the 3D-MIRGS in 21 patients (3D-MIRGS group) between February 2013 and February 2014. After preoperative planning, operations were real-time assisted using composite 3D-IDMs, which were fused with two-dimensional retrolaparoscopic images. The remaining 23 patients underwent surgery without 3D-MIRGS between May 2012 and February 2013; 14 of these patients were selected as a control group. Preoperative aspects and dimensions used for an anatomical score, "radius; exophytic/endophytic; nearness; anterior/posterior; location" nephrometry score, tumor size, operative time (OT), segmental renal artery clamping (SRAC) time, estimated blood loss (EBL), postoperative hospitalization, the preoperative serum creatinine level and ipsilateral glomerular filtration rate (GFR), as well as postoperative 6-month data were compared between groups. All the SRAC procedures were technically successful, and each targeted tumor was excised completely; final pathological margin results were negative. The OT was shorter (159.0 vs. 193.2 min; p < 0.001), and EBL (148.1 vs. 176.1 mL; p < 0.001) was reduced in the 3D-MIRGS group compared with controls. No statistically significant differences in SRAC time or postoperative hospitalization were found between the groups. Neither group showed any statistically significant increases in serum creatinine level or decreases in ipsilateral GFR postoperatively. Preoperative planning and real-time assisted surgical navigation using the 3D-IDM reconstructed from 3D-MIRGS and combined with the 3D laparoscopic system can facilitate LPN and result in precise SRAC and accurate excision of tumor that is both effective and safe.
Gibbs, Kenneth D; Basson, Jacob; Xierali, Imam M; Broniatowski, David A
2016-11-17
Faculty diversity is a longstanding challenge in the US. However, we lack a quantitative and systemic understanding of how the career transitions into assistant professor positions of PhD scientists from underrepresented minority (URM) and well-represented (WR) racial/ethnic backgrounds compare. Between 1980 and 2013, the number of PhD graduates from URM backgrounds increased by a factor of 9.3, compared with a 2.6-fold increase in the number of PhD graduates from WR groups. However, the number of scientists from URM backgrounds hired as assistant professors in medical school basic science departments was not related to the number of potential candidates (R 2 =0.12, p>0.07), whereas there was a strong correlation between these two numbers for scientists from WR backgrounds (R 2 =0.48, p<0.0001). We built and validated a conceptual system dynamics model based on these data that explained 79% of the variance in the hiring of assistant professors and posited no hiring discrimination. Simulations show that, given current transition rates of scientists from URM backgrounds to faculty positions, faculty diversity would not increase significantly through the year 2080 even in the context of an exponential growth in the population of PhD graduates from URM backgrounds, or significant increases in the number of faculty positions. Instead, the simulations showed that diversity increased as more postdoctoral candidates from URM backgrounds transitioned onto the market and were hired.
Acoustic Parametric Array for Identifying Standoff Targets
NASA Astrophysics Data System (ADS)
Hinders, M. K.; Rudd, K. E.
2010-02-01
An integrated simulation method for investigating nonlinear sound beams and 3D acoustic scattering from any combination of complicated objects is presented. A standard finite-difference simulation method is used to model pulsed nonlinear sound propagation from a source to a scattering target via the KZK equation. Then, a parallel 3D acoustic simulation method based on the finite integration technique is used to model the acoustic wave interaction with the target. Any combination of objects and material layers can be placed into the 3D simulation space to study the resulting interaction. Several example simulations are presented to demonstrate the simulation method and 3D visualization techniques. The combined simulation method is validated by comparing experimental and simulation data and a demonstration of how this combined simulation method assisted in the development of a nonlinear acoustic concealed weapons detector is also presented.
3D Segmentation with an application of level set-method using MRI volumes for image guided surgery.
Bosnjak, A; Montilla, G; Villegas, R; Jara, I
2007-01-01
This paper proposes an innovation in the application for image guided surgery using a comparative study of three different method of segmentation. This segmentation method is faster than the manual segmentation of images, with the advantage that it allows to use the same patient as anatomical reference, which has more precision than a generic atlas. This new methodology for 3D information extraction is based on a processing chain structured of the following modules: 1) 3D Filtering: the purpose is to preserve the contours of the structures and to smooth the homogeneous areas; several filters were tested and finally an anisotropic diffusion filter was used. 2) 3D Segmentation. This module compares three different methods: Region growing Algorithm, Cubic spline hand assisted, and Level Set Method. It then proposes a Level Set-based on the front propagation method that allows the making of the reconstruction of the internal walls of the anatomical structures of the brain. 3) 3D visualization. The new contribution of this work consists on the visualization of the segmented model and its use in the pre-surgery planning.
Amoli-Diva, Mitra; Taherimaslak, Zohreh; Allahyari, Mehdi; Pourghazi, Kamyar; Manafi, Mohammad Hanif
2015-03-01
An efficient, simple and fast low-density solvent based dispersive liquid-liquid microextraction (LDS-DLLME) followed by vortex-assisted dispersive solid phase extraction (VA-D-SPE) has been developed as a new approach for extraction and preconcentration of aflatoxin M1 in milk samples prior to its micelle enhanced spectrofluorimetic determination. In this LDS-DLLME coupled VA-D-SPE method, milk samples were first treated with methanol/water (80:20, v/v) after removing the fat layer. This solvent was directly used as the dispersing solvent in DLLME along with using 1-heptanol (as a low-density solvent with respect to water) as the extracting solvent. In VA-D-SPE approach, hydrophobic oleic acid modified Fe3O4 nanoparticles were used to retrieve the analyte from the DLLME step. It is considerably that the target of VA-D-SPE was 1-heptanol rather than the aflatoxin M1 directly. The main parameters affecting the efficiency of LDS-DLLME and VA-D-SPE procedures and signal enhancement of aflatoxin M1 were investigated and optimized. Under the optimum conditions, the method was linear in the range from 0.02 to 200 µg L(-1) with the correlation coefficient (R(2)) of 0.9989 and detection limit of 13 ng L(-1). The intra-day precision was 2.9 and 4.3% and the inter-day precision was 2.1 and 3.3% for concentration of 2 and 50 µg L(-1) respectively. The developed method was applied for extraction and preconcentration of AFM1 in three commercially available milk samples and the results were compared with the official AOAC method. Copyright © 2014 Elsevier B.V. All rights reserved.
Five-dimensional ultrasound system for soft tissue visualization.
Deshmukh, Nishikant P; Caban, Jesus J; Taylor, Russell H; Hager, Gregory D; Boctor, Emad M
2015-12-01
A five-dimensional ultrasound (US) system is proposed as a real-time pipeline involving fusion of 3D B-mode data with the 3D ultrasound elastography (USE) data as well as visualization of these fused data and a real-time update capability over time for each consecutive scan. 3D B-mode data assist in visualizing the anatomy of the target organ, and 3D elastography data adds strain information. We investigate the feasibility of such a system and show that an end-to-end real-time system, from acquisition to visualization, can be developed. We present a system that consists of (a) a real-time 3D elastography algorithm based on a normalized cross-correlation (NCC) computation on a GPU; (b) real-time 3D B-mode acquisition and network transfer; (c) scan conversion of 3D elastography and B-mode volumes (if acquired by 4D wobbler probe); and (d) visualization software that fuses, visualizes, and updates 3D B-mode and 3D elastography data in real time. We achieved a speed improvement of 4.45-fold for the threaded version of the NCC-based 3D USE versus the non-threaded version. The maximum speed was 79 volumes/s for 3D scan conversion. In a phantom, we validated the dimensions of a 2.2-cm-diameter sphere scan-converted to B-mode volume. Also, we validated the 5D US system visualization transfer function and detected 1- and 2-cm spherical objects (phantom lesion). Finally, we applied the system to a phantom consisting of three lesions to delineate the lesions from the surrounding background regions of the phantom. A 5D US system is achievable with real-time performance. We can distinguish between hard and soft areas in a phantom using the transfer functions.
Govsa, Figen; Yagdi, Tahir; Ozer, Mehmet Asim; Eraslan, Cenk; Alagoz, Ahmet Kemal
2017-02-01
The purpose of this study is to recreate live patient arterial anomalies using new recent application of three-dimensional (3D) printed anatomical models. Another purpose of building such models is to evaluate the effectiveness of angiographic data. With the help of the DICOM files from computed tomographic angiography (CT-A), we were able to build a printed model of variant course of the internal carotid artery (ICA). Images of coiling of the ICA taken by CT-A, were then converted into 3D images using Google SketchUp free software, and the images were saved in stereolithography format. Imaging helped us conduct the examination in details with reference to geometrical features of ICA, degree of curve, its extension, location and presence of loop. Challenging vascular anatomy was exposed with models of adverse curve of carotid anatomy, including highly angulated necks, conical necks, short necks, tortuous carotid arteries, and narrowed carotid lumens. It assisted us to comprehend spatial anatomy configuration of life-like models. 3D model can be very effective in cases when anatomical difficulties are detected through the CT-A, and therefore, a tactile approach is demanded preoperatively. 3D life-like models serve as an essential office-based tool in vascular surgery as they assist surgeons in preoperative planning, develop intraoperative guidance, teach both the patients and the surgical trainees, and simulate to show patient-specific procedures in medical field.
Computer Assisted Virtual Environment - CAVE
DOE Office of Scientific and Technical Information (OSTI.GOV)
Erickson, Phillip; Podgorney, Robert; Weingartner,
Research at the Center for Advanced Energy Studies is taking on another dimension with a 3-D device known as a Computer Assisted Virtual Environment. The CAVE uses projection to display high-end computer graphics on three walls and the floor. By wearing 3-D glasses to create depth perception and holding a wand to move and rotate images, users can delve into data.
Computer Assisted Virtual Environment - CAVE
Erickson, Phillip; Podgorney, Robert; Weingartner,
2018-05-30
Research at the Center for Advanced Energy Studies is taking on another dimension with a 3-D device known as a Computer Assisted Virtual Environment. The CAVE uses projection to display high-end computer graphics on three walls and the floor. By wearing 3-D glasses to create depth perception and holding a wand to move and rotate images, users can delve into data.
LoPresti, Melissa; Daniels, Bradley; Buchanan, Edward P; Monson, Laura; Lam, Sandi
2017-04-01
Repeat surgery for restenosis after initial nonsyndromic craniosynostosis intervention is sometimes needed. Calvarial vault reconstruction through a healed surgical bed adds a level of intraoperative complexity and may benefit from preoperative and intraoperative definitions of biometric and aesthetic norms. Computer-assisted design and manufacturing using 3D imaging allows the precise formulation of operative plans in anticipation of surgical intervention. 3D printing turns virtual plans into anatomical replicas, templates, or customized implants by using a variety of materials. The authors present a technical note illustrating the use of this technology: a repeat calvarial vault reconstruction that was planned and executed using computer-assisted design and 3D printed intraoperative guides.
Choi, Jin Woo; Roh, Hong Gee; Moon, Won-Jin; Kim, Na Ra; Moon, Sung Gyu; Kang, Chung Hwan; Chun, Young Il; Kang, Hyun-Seung
2011-01-01
To evaluate the usefulness of time-resolved contrast enhanced magnetic resonance angiography (4D MRA) after stent-assisted coil embolization by comparing it with time of flight (TOF)-MRA. TOF-MRA and 4D MRA were obtained by 3T MRI in 26 patients treated with stent-assisted coil embolization (Enterprise:Neuroform = 7:19). The qualities of the MRA were rated on a graded scale of 0 to 4. We classified completeness of endovascular treatment into three categories. The degree of quality of visualization of the stented artery was compared between TOF and 4D MRA by the Wilcoxon signed rank test. We used the Mann-Whitney U test for comparing the quality of the visualization of the stented artery according to the stent type in each MRA method. The quality in terms of the visualization of the stented arteries in 4D MRA was significantly superior to that in 3D TOF-MRA, regardless of type of the stent (p < 0.001). The quality of the arteries which were stented with Neuroform was superior to that of the arteries stented with Enterprise in 3D TOF (p < 0.001) and 4D MRA (p = 0.008), respectively. 4D MRA provides a higher quality view of the stented parent arteries when compared with TOF.
Implementation of 3D virtual learning environment to improve students’ cognitive achievement
NASA Astrophysics Data System (ADS)
Rasim; Langi, A. Z. R.; Rosmansyah, Y.; Munir
2018-05-01
Virtual Learning Environment (VLE) has been widely used in assisting learning. This study aims to implement VLE-based learning in software engineering course. VLE provides many facilities for learning. In this research, VLE components used were presenter and quiz chair components. Evaluation results showed a significant difference from classical learning.
45 CFR 201.14 - Reconsideration under section 1116(d) of the Act.
Code of Federal Regulations, 2010 CFR
2010-10-01
... SERVICES GRANTS TO STATES FOR PUBLIC ASSISTANCE PROGRAMS Review and Audits § 201.14 Reconsideration under... audit) which contain the findings of fact on which the disallowance determination is based; (vi... reports of audit or review which were the basis for his decision. (3) The Administrator shall promptly...
45 CFR 201.14 - Reconsideration under section 1116(d) of the Act.
Code of Federal Regulations, 2011 CFR
2011-10-01
... SERVICES GRANTS TO STATES FOR PUBLIC ASSISTANCE PROGRAMS Review and Audits § 201.14 Reconsideration under... audit) which contain the findings of fact on which the disallowance determination is based; (vi... reports of audit or review which were the basis for his decision. (3) The Administrator shall promptly...
Techniques for the rapid display and manipulation of 3-D biomedical data.
Goldwasser, S M; Reynolds, R A; Talton, D A; Walsh, E S
1988-01-01
The use of fully interactive 3-D workstations with true real-time performance will become increasingly common as technology matures and economical commercial systems become available. This paper provides a comprehensive introduction to high speed approaches to the display and manipulation of 3-D medical objects obtained from tomographic data acquisition systems such as CT, MR, and PET. A variety of techniques are outlined including the use of software on conventional minicomputers, hardware assist devices such as array processors and programmable frame buffers, and special purpose computer architecture for dedicated high performance systems. While both algorithms and architectures are addressed, the major theme centers around the utilization of hardware-based approaches including parallel processors for the implementation of true real-time systems.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Tsauo, Jiaywei, E-mail: 80732059@qq.com; Luo, Xuefeng, E-mail: luobo-913@126.com; Ye, Linchao, E-mail: linchao.ye@siemens.com
2015-06-15
PurposeThis study was designed to report our results with a modified technique of three-dimensional (3D) path planning software assisted transjugular intrahepatic portosystemic shunt (TIPS).Methods3D path planning software was recently developed to facilitate TIPS creation by using two carbon dioxide portograms acquired at least 20° apart to generate a 3D path for overlay needle guidance. However, one shortcoming is that puncturing along the overlay would be technically impossible if the angle of the liver access set and the angle of the 3D path are not the same. To solve this problem, a prototype 3D path planning software was fitted with a utility to calculate themore » angle of the 3D path. Using this, we modified the angle of the liver access set accordingly during the procedure in ten patients.ResultsFailure for technical reasons occurred in three patients (unsuccessful wedged hepatic venography in two cases, software technical failure in one case). The procedure was successful in the remaining seven patients, and only one needle pass was required to obtain portal vein access in each case. The course of puncture was comparable to the 3D path in all patients. No procedure-related complication occurred following the procedures.ConclusionsAdjusting the angle of the liver access set to match the angle of the 3D path determined by the software appears to be a favorable modification to the technique of 3D path planning software assisted TIPS.« less
Asfaram, Arash; Ghaedi, Mehrorang; Abidi, Hassan; Javadian, Hamedreza; Zoladl, Mohammad; Sadeghfar, Fardin
2018-06-01
A simple procedure based on ultrasound-assisted (UA) dispersive micro solid phase extraction (D-μ-SPE) was applied for sorption of trace amount Allura Red (AR) in fruit juice and water samples. After loading process by UA-D-μ-SPE, the concentrated AR was eluted and monitored using high-performance liquid chromatography-ultraviolet -visible detector (HPLC-UV). The best operational conditions were obtained as follows: pH = 3.0, 8 mg of the sorbent, sonication time of 4.5 min and 0.16 mL of THF as elution solvent. Under the optimum operational conditions, the present method was acceptable for AR quantification in the range of 1.0-5000 ng mL -1 . The repeatability based on RSD with the amount of 1.67-3.18%, low LOD (0.198 ng mL -1 ) and LOQ (0.659 ng mL -1 ) were obtained. The UA-D-μ-SPE-HPLC-UV method was successfully applied for trace quantification of AR from water and commercial fruit juice samples supplied from local supermarkets, and acceptable relative recoveries over the range of 97.7-105.4% with RSDs ≤5.50% were obtained. Copyright © 2018 Elsevier B.V. All rights reserved.
3D printable highly conductive and mechanically strong thermoplastic-based nanocomposites
NASA Astrophysics Data System (ADS)
Tabiai, Ilyass; Therriault, Daniel
Highly conductive 3D printable inks can be used to design electrical devices with various functionalities and geometries. We use the solvent evaporation assisted 3D-printing method to create high resolution structures made of poly(lactid) acid (PLA) reinforced with multi-walled carbon nanotube (MWCNTs). We characterize fibers with diameters ranging between 100 μm to 330 μm and reinforced with MWCNTs from 0.5 up to 40wt% here. Tensile test, shrinkage ratio, density and electrical conductivity measurements of the printed nanocomposite are presented. The material's electrical conductivity is strongly improved by adding MWCNTs (up to 3000S/m), this value was found to be higher than any 3D-printable carbon based material available in the literature. It is observed that MWCNTs significantly increase the material's strength and stiffness while reducing its ductility. The ink's density was also higher while still being in the range of polymers' densities. The presented nanocomposite is light weight, highly conductive, has good mechanical properties and can be printed in a freeform fashion at the micro scale. A myriad of low power consumption with less resistive heating sensors and devices can potentially be designed using it and integrated into other 3D printable products.
Li, Meng; Wang, Jun; Yang, Yuezhou; Xie, Guanghui
2016-05-01
Jerusalem artichoke (JA) has been known as a potential nonfood feedstock for biofuels. Based on systems analysis of total 59 accessions, both soluble sugar and ash could positively affect biomass digestibility after dilute sodium hydroxide pretreatment (A). In this study, one representative accession (HEN-3) was used to illustrate its enzymatic digestibility with pretreatments of ultrasonic-assisted dilute sodium hydroxide (B), alkaline peroxide (C), and ultrasonic-assisted alkaline peroxide (D). Pretreatment D exhibited the highest hexose release rate (79.4%) and total sugar yield (10.4 g/L), which were 2.4 and 2.6 times higher, respectively, than those of the control. The analysis of cellulose crystalline index (CrI), cellulose degree of polymerization (DP), thermal behavior and SEM suggested that alkali-based pretreatments could distinctively extract lignin and pectin polymers, leading to significant alterations of cellulose CrI and DP for high biomass saccharification. Additionally, hydrogen peroxide (H2O2) could significant reduce the generation of fermentation inhibitors during alkali-based pretreatments. Copyright © 2016 Elsevier Ltd. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Dai, Wubin; Lei, Yifeng; Zhou, Jia
In this work, we have succeeded in obtaining high quality warm w-light-emitting-diodes (LEDs) by adopting hybrid two-dimensional (2D) structure of SiNx photonic crystal layer (PCL) assisted cyan-emitting ceramic-plate thiosilicate SrLa2Si2S8:Ce3+ with red-emitting film SrLiAl3N4:Eu2+ phosphor on a 430 nm blue LED chip at 350 mA. 2D SiNx PCL was capped with thiosilicate is because it can enhance the luminous efficacy and maintain the low correlated color temperature (CCT) and high color-rendering index (CRI). High luminous efficacy (82.3 lm/W), high special CRI (R9=75) as well as the low CCT (5431 K) of the optimal w-LED was obtained due to the assistancesmore » of 2D SiNx PCL and narrow-band red-emitting phosphor with the doping percentage at 10 wt%. The synthesis processes, structural analysis, optical properties and LED device performances were detailed investigated to find out the relationship between the optimum composition and good optical properties. Based on intriguing luminescence properties by the 2D SiNx PCL and red-emitting film phosphor introducing, we proclaim this method could also have high potential application in other phosphor-converted w-LEDs.« less
Song, Hongning; Zhou, Qing; Zhang, Lan; Deng, Qing; Wang, Yijia; Hu, Bo; Tan, Tuantuan; Chen, Jinling; Pan, Yiteng; He, Fazhi
2017-01-01
Abstract The novel 3-dimensional printing (3DP) technique has shown its ability to assist personalized cardiac intervention therapy. This study aimed to determine the feasibility of 3D-printed left atrial appendage (LAA) models based on 3D transesophageal echocardiography (3D TEE) data and their application value in treating LAA occlusions. Eighteen patients with transcatheter LAA occlusion, and preprocedure 3D TEE and cardiac computed tomography were enrolled. 3D TEE volumetric data of the LAA were acquired and postprocessed for 3DP. Two types of 3D models of the LAA (ie, hard chamber model and flexible wall model) were printed by a 3D printer. The morphological classification and lobe identification of the LAA were assessed by the 3D chamber model, and LAA dimensions were measured via the 3D wall model. Additionally, a simulation operative rehearsal was performed on the 3D models in cases of challenging LAA morphology for the purpose of understanding the interactions between the device and the model. Three-dimensional TEE volumetric data of the LAA were successfully reprocessed and printed as 3D LAA chamber models and 3D LAA wall models in all patients. The consistency of the morphological classifications of the LAA based on 3D models and cardiac computed tomography was 0.92 (P < .01). The differences between the LAA ostium dimensions and depth measured using the 3D models were not significant from those measured on 3D TEE (P > .05). A simulation occlusion was successfully performed on the 3D model of the 2 challenging cases and compared with the real procedure. The echocardiographic 3DP technique is feasible and accurate in reflecting the spatial morphology of the LAA, which may be promising for the personalized planning of transcatheter LAA occlusion. PMID:28930824
Lewis, Brett B.; Winkler, Robert; Sang, Xiahan; ...
2017-04-07
Here, we investigate the growth, purity, grain structure/morphology, and electrical resistivity of 3D platinum nanowires synthesized via electron beam induced deposition with and without an in situ pulsed laser assist process which photothermally couples to the growing Pt–C deposits. Notably, we demonstrate: 1) higher platinum concentration and a coalescence of the otherwise Pt–C nanogranular material, 2) a slight enhancement in the deposit resolution and 3) a 100-fold improvement in the conductivity of suspended nanowires grown with the in situ photothermal assist process, while retaining a high degree of shape fidelity.
A three-dimensional digital atlas of the dura mater based on human head MRI.
Yang, Zhirong; Guo, Zhilin
2015-03-30
The goal of this paper was to design a three-dimensional (3D) digital dural atlas of the human brain for assisting neurosurgeons during the planning of an operation, medical research and teaching activities in neurosurgical anatomy. The 176 sagittal head magnetic resonance(MR) images of a 54-year-old female who suffered from the left posterior fossa tumor were processed and outlined, based on which a 3D dural model was created using the softwares of 3ds-max and Mimics. Then the model and images/anatomy photos were matched using the softwares of Z-brush and Photoshop to form the 3-D dural atlas. Dural anatomic photographs were needed to produce the 3D atlas in dural vault and skull base areas. The 3D dural atlas of the brain and related structures was successfully constructed using 73 dural delineations, the contours of dural model match very well on the dural structures of the original images in three orthogonal (axial, coronal and sagittal view) MR cross-sections. The atlas can be arbitrarily rotated and viewed from any direction. It can also be zoomed in and out directly using the zoom function. We successfully generated a 3D dural atlas of human brain, which can be used for repeated observation and research without limitations of time and shortage of corpses. In addition, the atlas has many potential applications in operative planning, surgical training, teaching activities, and so on. Copyright © 2014 Elsevier B.V. All rights reserved.
Shape‐Controlled, Self‐Wrapped Carbon Nanotube 3D Electronics
Wang, Huiliang; Wang, Yanming; Tee, Benjamin C.‐K.; Kim, Kwanpyo; Lopez, Jeffrey; Cai, Wei
2015-01-01
The mechanical flexibility and structural softness of ultrathin devices based on organic thin films and low‐dimensional nanomaterials have enabled a wide range of applications including flexible display, artificial skin, and health monitoring devices. However, both living systems and inanimate systems that are encountered in daily lives are all 3D. It is therefore desirable to either create freestanding electronics in a 3D form or to incorporate electronics onto 3D objects. Here, a technique is reported to utilize shape‐memory polymers together with carbon nanotube flexible electronics to achieve this goal. Temperature‐assisted shape control of these freestanding electronics in a programmable manner is demonstrated, with theoretical analysis for understanding the shape evolution. The shape control process can be executed with prepatterned heaters, desirable for 3D shape formation in an enclosed environment. The incorporation of carbon nanotube transistors, gas sensors, temperature sensors, and memory devices that are capable of self‐wrapping onto any irregular shaped‐objects without degradations in device performance is demonstrated. PMID:27980972
Real-time advanced spinal surgery via visible patient model and augmented reality system.
Wu, Jing-Ren; Wang, Min-Liang; Liu, Kai-Che; Hu, Ming-Hsien; Lee, Pei-Yuan
2014-03-01
This paper presents an advanced augmented reality system for spinal surgery assistance, and develops entry-point guidance prior to vertebroplasty spinal surgery. Based on image-based marker detection and tracking, the proposed camera-projector system superimposes pre-operative 3-D images onto patients. The patients' preoperative 3-D image model is registered by projecting it onto the patient such that the synthetic 3-D model merges with the real patient image, enabling the surgeon to see through the patients' anatomy. The proposed method is much simpler than heavy and computationally challenging navigation systems, and also reduces radiation exposure. The system is experimentally tested on a preoperative 3D model, dummy patient model and animal cadaver model. The feasibility and accuracy of the proposed system is verified on three patients undergoing spinal surgery in the operating theater. The results of these clinical trials are extremely promising, with surgeons reporting favorably on the reduced time of finding a suitable entry point and reduced radiation dose to patients. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.
October 2003 Status of Forces Survey of DoD Civilians: Tabulations of Responses
2004-03-01
182 e. Employee assistance programs .............................................................. 184 f. Support groups...202 60. Mark your level of satisfaction with employee assistance programs ..............204 61. Mark your level of satisfaction...services provided by your organization? e. Employee assistance programs 1. Yes 2. No 3. Not available Percentages Percent Responding 1 2 3 Max
An automated method for accurate vessel segmentation.
Yang, Xin; Liu, Chaoyue; Le Minh, Hung; Wang, Zhiwei; Chien, Aichi; Cheng, Kwang-Ting Tim
2017-05-07
Vessel segmentation is a critical task for various medical applications, such as diagnosis assistance of diabetic retinopathy, quantification of cerebral aneurysm's growth, and guiding surgery in neurosurgical procedures. Despite technology advances in image segmentation, existing methods still suffer from low accuracy for vessel segmentation in the two challenging while common scenarios in clinical usage: (1) regions with a low signal-to-noise-ratio (SNR), and (2) at vessel boundaries disturbed by adjacent non-vessel pixels. In this paper, we present an automated system which can achieve highly accurate vessel segmentation for both 2D and 3D images even under these challenging scenarios. Three key contributions achieved by our system are: (1) a progressive contrast enhancement method to adaptively enhance contrast of challenging pixels that were otherwise indistinguishable, (2) a boundary refinement method to effectively improve segmentation accuracy at vessel borders based on Canny edge detection, and (3) a content-aware region-of-interests (ROI) adjustment method to automatically determine the locations and sizes of ROIs which contain ambiguous pixels and demand further verification. Extensive evaluation of our method is conducted on both 2D and 3D datasets. On a public 2D retinal dataset (named DRIVE (Staal 2004 IEEE Trans. Med. Imaging 23 501-9)) and our 2D clinical cerebral dataset, our approach achieves superior performance to the state-of-the-art methods including a vesselness based method (Frangi 1998 Int. Conf. on Medical Image Computing and Computer-Assisted Intervention) and an optimally oriented flux (OOF) based method (Law and Chung 2008 European Conf. on Computer Vision). An evaluation on 11 clinical 3D CTA cerebral datasets shows that our method can achieve 94% average accuracy with respect to the manual segmentation reference, which is 23% to 33% better than the five baseline methods (Yushkevich 2006 Neuroimage 31 1116-28; Law and Chung 2008 European Conf. on Computer Vision; Law and Chung 2009 IEEE Trans. Image Process. 18 596-612; Wang 2015 J. Neurosci. Methods 241 30-6) with manually optimized parameters. Our system has also been applied clinically for cerebral aneurysm development analysis. Experimental results on 10 patients' data, with two 3D CT scans per patient, show that our system's automatic diagnosis outcomes are consistent with clinicians' manual measurements.
An automated method for accurate vessel segmentation
NASA Astrophysics Data System (ADS)
Yang, Xin; Liu, Chaoyue; Le Minh, Hung; Wang, Zhiwei; Chien, Aichi; (Tim Cheng, Kwang-Ting
2017-05-01
Vessel segmentation is a critical task for various medical applications, such as diagnosis assistance of diabetic retinopathy, quantification of cerebral aneurysm’s growth, and guiding surgery in neurosurgical procedures. Despite technology advances in image segmentation, existing methods still suffer from low accuracy for vessel segmentation in the two challenging while common scenarios in clinical usage: (1) regions with a low signal-to-noise-ratio (SNR), and (2) at vessel boundaries disturbed by adjacent non-vessel pixels. In this paper, we present an automated system which can achieve highly accurate vessel segmentation for both 2D and 3D images even under these challenging scenarios. Three key contributions achieved by our system are: (1) a progressive contrast enhancement method to adaptively enhance contrast of challenging pixels that were otherwise indistinguishable, (2) a boundary refinement method to effectively improve segmentation accuracy at vessel borders based on Canny edge detection, and (3) a content-aware region-of-interests (ROI) adjustment method to automatically determine the locations and sizes of ROIs which contain ambiguous pixels and demand further verification. Extensive evaluation of our method is conducted on both 2D and 3D datasets. On a public 2D retinal dataset (named DRIVE (Staal 2004 IEEE Trans. Med. Imaging 23 501-9)) and our 2D clinical cerebral dataset, our approach achieves superior performance to the state-of-the-art methods including a vesselness based method (Frangi 1998 Int. Conf. on Medical Image Computing and Computer-Assisted Intervention) and an optimally oriented flux (OOF) based method (Law and Chung 2008 European Conf. on Computer Vision). An evaluation on 11 clinical 3D CTA cerebral datasets shows that our method can achieve 94% average accuracy with respect to the manual segmentation reference, which is 23% to 33% better than the five baseline methods (Yushkevich 2006 Neuroimage 31 1116-28; Law and Chung 2008 European Conf. on Computer Vision; Law and Chung 2009 IEEE Trans. Image Process. 18 596-612; Wang 2015 J. Neurosci. Methods 241 30-6) with manually optimized parameters. Our system has also been applied clinically for cerebral aneurysm development analysis. Experimental results on 10 patients’ data, with two 3D CT scans per patient, show that our system’s automatic diagnosis outcomes are consistent with clinicians’ manual measurements.
NASA Astrophysics Data System (ADS)
Liang, Liying; Xu, Yimeng; Lei, Yong; Liu, Haimei
2014-03-01
Three-dimensional (3D) porous composite aerogels have been synthesized via an innovative in situ hydrothermal method assisted by a freeze-drying process. In this hybrid structure, one-dimensional (1D) AgVO3 nanowires are uniformly dispersed on two-dimensional (2D) graphene nanosheet surfaces and/or are penetrated through the graphene sheets, forming 3D porous composite aerogels. As cathode materials for lithium-ion batteries, the composite aerogels exhibit high discharge capacity, excellent rate capability, and good cycling stability.Three-dimensional (3D) porous composite aerogels have been synthesized via an innovative in situ hydrothermal method assisted by a freeze-drying process. In this hybrid structure, one-dimensional (1D) AgVO3 nanowires are uniformly dispersed on two-dimensional (2D) graphene nanosheet surfaces and/or are penetrated through the graphene sheets, forming 3D porous composite aerogels. As cathode materials for lithium-ion batteries, the composite aerogels exhibit high discharge capacity, excellent rate capability, and good cycling stability. Electronic supplementary information (ESI) available: Preparation, characterization, SEM images, XRD patterns, and XPS of AgVO3/GAs. See DOI: 10.1039/c3nr06899d
Hung, Chun-Chi; Li, Yuan-Ta; Chou, Yu-Ching; Chen, Jia-En; Wu, Chia-Chun; Shen, Hsain-Chung; Yeh, Tsu-Te
2018-05-03
Treating pelvic fractures remains a challenging task for orthopaedic surgeons. We aimed to evaluate the feasibility, accuracy, and effectiveness of three-dimensional (3D) printing technology and computer-assisted virtual surgery for pre-operative planning in anterior ring fractures of the pelvis. We hypothesized that using 3D printing models would reduce operation time and significantly improve the surgical outcomes of pelvic fracture repair. We retrospectively reviewed the records of 30 patients with pelvic fractures treated by anterior pelvic fixation with locking plates (14 patients, conventional locking plate fixation; 16 patients, pre-operative virtual simulation with 3D, printing-assisted, pre-contoured, locking plate fixation). We compared operative time, instrumentation time, blood loss, and post-surgical residual displacements, as evaluated on X-ray films, among groups. Statistical analyses evaluated significant differences between the groups for each of these variables. The patients treated with the virtual simulation and 3D printing-assisted technique had significantly shorter internal fixation times, shorter surgery duration, and less blood loss (- 57 minutes, - 70 minutes, and - 274 ml, respectively; P < 0.05) than patients in the conventional surgery group. However, the post-operative radiological result was similar between groups (P > 0.05). The complication rate was less in the 3D printing group (1/16 patients) than in the conventional surgery group (3/14 patients). The 3D simulation and printing technique is an effective and reliable method for treating anterior pelvic ring fractures. With precise pre-operative planning and accurate execution of the procedures, this time-saving approach can provide a more personalized treatment plan, allowing for a safer orthopaedic surgery.
Automated 3D ultrasound image segmentation for assistant diagnosis of breast cancer
NASA Astrophysics Data System (ADS)
Wang, Yuxin; Gu, Peng; Lee, Won-Mean; Roubidoux, Marilyn A.; Du, Sidan; Yuan, Jie; Wang, Xueding; Carson, Paul L.
2016-04-01
Segmentation of an ultrasound image into functional tissues is of great importance to clinical diagnosis of breast cancer. However, many studies are found to segment only the mass of interest and not all major tissues. Differences and inconsistencies in ultrasound interpretation call for an automated segmentation method to make results operator-independent. Furthermore, manual segmentation of entire three-dimensional (3D) ultrasound volumes is time-consuming, resource-intensive, and clinically impractical. Here, we propose an automated algorithm to segment 3D ultrasound volumes into three major tissue types: cyst/mass, fatty tissue, and fibro-glandular tissue. To test its efficacy and consistency, the proposed automated method was employed on a database of 21 cases of whole breast ultrasound. Experimental results show that our proposed method not only distinguishes fat and non-fat tissues correctly, but performs well in classifying cyst/mass. Comparison of density assessment between the automated method and manual segmentation demonstrates good consistency with an accuracy of 85.7%. Quantitative comparison of corresponding tissue volumes, which uses overlap ratio, gives an average similarity of 74.54%, consistent with values seen in MRI brain segmentations. Thus, our proposed method exhibits great potential as an automated approach to segment 3D whole breast ultrasound volumes into functionally distinct tissues that may help to correct ultrasound speed of sound aberrations and assist in density based prognosis of breast cancer.
On Wings: Aerodynamics of Eagles.
ERIC Educational Resources Information Center
Millson, David
2000-01-01
The Aerodynamics Wing Curriculum is a high school program that combines basic physics, aerodynamics, pre-engineering, 3D visualization, computer-assisted drafting, computer-assisted manufacturing, production, reengineering, and success in a 15-hour, 3-week classroom module. (JOW)
Wen, Guodao; Cong, ZiXiang; Liu, KaiDong; Tang, Chao; Zhong, Chunyu; Li, Liwen; Dai, XuJie; Ma, Chiyuan
2016-06-01
We aimed to present a practical three-dimensional (3D) printed simulator to comprehensively and effectively accelerate the learning curve of endoscopic endonasal transsphenoidal surgery (EETS). The 3D printed simulator consists of three parts: (1) skull frame, (2) the nasal passage and the nasal alar of the face, and (3) a modified sella turcica. We aimed to improve three basic operational skills of surgeons: drilling, curetting, and aspirating. Eighteen neurosurgeons and five post-graduates were recruited and consented for the training. For trainees, (1) as the training progressed, the scores increased gradually, (2) a significant increase in the average scores was observed in the tenth training compared to the first training, and (3) there is a significant decrease in trainee variability in the shortening of the gap. The 18 neurosurgeons were divided into three groups: experts, assistants, and observers. For all three basic operations, (1) the average score of experts was obviously higher than that of the assistants, observers, and trainees' tenth training and (2) the average scores of assistants and observers were obviously higher than that of trainees' first training. A significant high in the average score between the assistants and the observers was seen for aspirating, but not for drilling or curetting. For curetting and aspirating, the tenth training average score of trainees was obviously higher than that of assistants and observers. This 3D printed simulator allows different endoscopic basic operations to be simulated and improves the EETS techniques of surgeons. We believed it to be a practical, simple, and low-cost simulator.
Evaluation of targeting errors in ultrasound-assisted radiotherapy
Wang, Michael; Rohling, Robert; Duzenli, Cheryl; Clark, Brenda; Archip, Neculai
2014-01-01
A method for validating the start-to-end accuracy of a 3D ultrasound-based patient positioning system for radiotherapy is described. A radiosensitive polymer gel is used to record the actual dose delivered to a rigid phantom after being positioned using 3D ultrasound guidance. Comparison of the delivered dose with the treatment plan allows accuracy of the entire radiotherapy treatment process, from simulation to 3D ultrasound guidance, and finally delivery of radiation, to be evaluated. The 3D ultrasound patient positioning system has a number of features for achieving high accuracy and reducing operator dependence. These include using tracked 3D ultrasound scans of the target anatomy acquired using a dedicated 3D ultrasound probe during both the simulation and treatment sessions, automatic 3D ultrasound-to-ultrasound registration, and use of infra-red LED (IRED) markers of the optical position sensing system for registering simulation CT to ultrasound data. The mean target localization accuracy of this system was 2.5mm for four target locations inside the phantom, compared to 1.6mm obtained using the conventional patient positioning method of laser alignment. Since the phantom is rigid, this represents the best possible set-up accuracy of the system. Thus, these results suggest that 3D ultrasound-based target localization is practically feasible and potentially capable of increasing the accuracy of patient positioning for radiotherapy in sites where day-to-day organ shifts are greater than 1mm in magnitude. PMID:18723271
Kuang, Xiao; Chen, Kaijuan; Dunn, Conner K; Wu, Jiangtao; Li, Vincent C F; Qi, H Jerry
2018-02-28
The three-dimensional (3D) printing of flexible and stretchable materials with smart functions such as shape memory (SM) and self-healing (SH) is highly desirable for the development of future 4D printing technology for myriad applications, such as soft actuators, deployable smart medical devices, and flexible electronics. Here, we report a novel ink that can be used for the 3D printing of highly stretchable, SM, and SH elastomer via UV-light-assisted direct-ink-write printing. An ink containing urethane diacrylate and a linear semicrystalline polymer is developed for the 3D printing of a semi-interpenetrating polymer network elastomer that can be stretched by up to 600%. The 3D-printed complex structures show interesting functional properties, such as high strain SM and SM -assisted SH capability. We demonstrate that such a 3D-printed SM elastomer has the potential application for biomedical devices, such as vascular repair devices. This research paves a new way for the further development of novel 4D printing, soft robotics, and biomedical devices.
A web-based instruction module for interpretation of craniofacial cone beam CT anatomy.
Hassan, B A; Jacobs, R; Scarfe, W C; Al-Rawi, W T
2007-09-01
To develop a web-based module for learner instruction in the interpretation and recognition of osseous anatomy on craniofacial cone-beam CT (CBCT) images. Volumetric datasets from three CBCT systems were acquired (i-CAT, NewTom 3G and AccuiTomo FPD) for various subjects using equipment-specific scanning protocols. The datasets were processed using multiple software to provide two-dimensional (2D) multiplanar reformatted (MPR) images (e.g. sagittal, coronal and axial) and three-dimensional (3D) visual representations (e.g. maximum intensity projection, minimum intensity projection, ray sum, surface and volume rendering). Distinct didactic modules which illustrate the principles of CBCT systems, guided navigation of the volumetric dataset, and anatomic correlation of 3D models and 2D MPR graphics were developed using a hybrid combination of web authoring and image analysis techniques. Interactive web multimedia instruction was facilitated by the use of dynamic highlighting and labelling, and rendered video illustrations, supplemented with didactic textual material. HTML coding and Java scripting were heavily implemented for the blending of the educational modules. An interactive, multimedia educational tool for visualizing the morphology and interrelationships of osseous craniofacial anatomy, as depicted on CBCT MPR and 3D images, was designed and implemented. The present design of a web-based instruction module may assist radiologists and clinicians in learning how to recognize and interpret the craniofacial anatomy of CBCT based images more efficiently.
Real-time 3D image reconstruction guidance in liver resection surgery.
Soler, Luc; Nicolau, Stephane; Pessaux, Patrick; Mutter, Didier; Marescaux, Jacques
2014-04-01
Minimally invasive surgery represents one of the main evolutions of surgical techniques. However, minimally invasive surgery adds difficulty that can be reduced through computer technology. From a patient's medical image [US, computed tomography (CT) or MRI], we have developed an Augmented Reality (AR) system that increases the surgeon's intraoperative vision by providing a virtual transparency of the patient. AR is based on two major processes: 3D modeling and visualization of anatomical or pathological structures appearing in the medical image, and the registration of this visualization onto the real patient. We have thus developed a new online service, named Visible Patient, providing efficient 3D modeling of patients. We have then developed several 3D visualization and surgical planning software tools to combine direct volume rendering and surface rendering. Finally, we have developed two registration techniques, one interactive and one automatic providing intraoperative augmented reality view. From January 2009 to June 2013, 769 clinical cases have been modeled by the Visible Patient service. Moreover, three clinical validations have been realized demonstrating the accuracy of 3D models and their great benefit, potentially increasing surgical eligibility in liver surgery (20% of cases). From these 3D models, more than 50 interactive AR-assisted surgical procedures have been realized illustrating the potential clinical benefit of such assistance to gain safety, but also current limits that automatic augmented reality will overcome. Virtual patient modeling should be mandatory for certain interventions that have now to be defined, such as liver surgery. Augmented reality is clearly the next step of the new surgical instrumentation but remains currently limited due to the complexity of organ deformations during surgery. Intraoperative medical imaging used in new generation of automated augmented reality should solve this issue thanks to the development of Hybrid OR.
Ahanhanzo, Y Glèlè; Palenfo, D; Saussier, C; Gbèdonou, P; Tonda, A; Da Silva, A; Aplogan, A
2016-08-01
Within the framework of its strategic goal of vaccine coverage (VC) improvement, GAVI, The Vaccine Alliance has entrusted the Agence de médecine préventive (agency for preventive medicine, AMP) with technical assistance services to Cameroon, Cote d'Ivoire (Ivory Coast), and Mauritania. This support was provided to selected priority districts (PDs) with the worst Penta3 coverage performances. In 2014, PDs benefited from technical and management capacities in vaccinology strengthening for district medical officers, supportive supervisions and technical assistance in health logistics, data management and quality. We analyzed the effects of the AMP technical assistance on the improvement of the cumulative Penta3 coverage, which is the key performance indicator of the expanded programme on immunization (EPI) performance. We compared Penta3 coverage between PDs and other non-priority districts (NPDs), Penta3 coverage evolution within each PD, and the distribution of PDs and NPDs according to Penta3 coverage category between January and December 2014. Technical assistance had a positive effect on the EPI performance. Indeed Penta3 coverage progression was higher in PDs than in NPDs throughout the period. Besides, between January and December 2014, the Penta3 VC increased in 70%, 100% and 86% of DPs in Cameroon, Côte d'Ivoire and Mauritania, respectively. Furthermore, the increase in the number of PDs with a Penta3 coverage over 80% was higher in DPs than in NPDs: 20% versus 8% for Cameroon, 58% versus 29% for Côte d'Ivoire and 17% versus 8% for Mauritania. Despite positive and encouraging results, this technical assistance service can be improved and efforts are needed to ensure that all health districts have a VC above 80% for all EPI vaccines. The current challenge is for African countries to mobilize resources for maintaining the knowledge and benefits and scaling such interventions in the public health area.
Gibbs, Kenneth D; Basson, Jacob; Xierali, Imam M; Broniatowski, David A
2016-01-01
Faculty diversity is a longstanding challenge in the US. However, we lack a quantitative and systemic understanding of how the career transitions into assistant professor positions of PhD scientists from underrepresented minority (URM) and well-represented (WR) racial/ethnic backgrounds compare. Between 1980 and 2013, the number of PhD graduates from URM backgrounds increased by a factor of 9.3, compared with a 2.6-fold increase in the number of PhD graduates from WR groups. However, the number of scientists from URM backgrounds hired as assistant professors in medical school basic science departments was not related to the number of potential candidates (R2=0.12, p>0.07), whereas there was a strong correlation between these two numbers for scientists from WR backgrounds (R2=0.48, p<0.0001). We built and validated a conceptual system dynamics model based on these data that explained 79% of the variance in the hiring of assistant professors and posited no hiring discrimination. Simulations show that, given current transition rates of scientists from URM backgrounds to faculty positions, faculty diversity would not increase significantly through the year 2080 even in the context of an exponential growth in the population of PhD graduates from URM backgrounds, or significant increases in the number of faculty positions. Instead, the simulations showed that diversity increased as more postdoctoral candidates from URM backgrounds transitioned onto the market and were hired. DOI: http://dx.doi.org/10.7554/eLife.21393.001 PMID:27852433
A university/industry panel will report on the progress and findings of a fivesteve-year project funded by the US Environmental Protection Agency. The project's end product will be a Web-based, 3D computer-simulated residential environment with a decision support system to assist...
Nomura, Yukihiro; Higaki, Toru; Fujita, Masayo; Miki, Soichiro; Awaya, Yoshikazu; Nakanishi, Toshio; Yoshikawa, Takeharu; Hayashi, Naoto; Awai, Kazuo
2017-02-01
This study aimed to evaluate the effects of iterative reconstruction (IR) algorithms on computer-assisted detection (CAD) software for lung nodules in ultra-low-dose computed tomography (ULD-CT) for lung cancer screening. We selected 85 subjects who underwent both a low-dose CT (LD-CT) scan and an additional ULD-CT scan in our lung cancer screening program for high-risk populations. The LD-CT scans were reconstructed with filtered back projection (FBP; LD-FBP). The ULD-CT scans were reconstructed with FBP (ULD-FBP), adaptive iterative dose reduction 3D (AIDR 3D; ULD-AIDR 3D), and forward projected model-based IR solution (FIRST; ULD-FIRST). CAD software for lung nodules was applied to each image dataset, and the performance of the CAD software was compared among the different IR algorithms. The mean volume CT dose indexes were 3.02 mGy (LD-CT) and 0.30 mGy (ULD-CT). For overall nodules, the sensitivities of CAD software at 3.0 false positives per case were 78.7% (LD-FBP), 9.3% (ULD-FBP), 69.4% (ULD-AIDR 3D), and 77.8% (ULD-FIRST). Statistical analysis showed that the sensitivities of ULD-AIDR 3D and ULD-FIRST were significantly higher than that of ULD-FBP (P < .001). The performance of CAD software in ULD-CT was improved by using IR algorithms. In particular, the performance of CAD in ULD-FIRST was almost equivalent to that in LD-FBP. Copyright © 2017 The Association of University Radiologists. Published by Elsevier Inc. All rights reserved.
Synthesis and luminescent properties of spindle-like CaWO{sub 4}:Sm{sup 3+} phosphors
DOE Office of Scientific and Technical Information (OSTI.GOV)
Tian, Yue; Department of Physics, Dalian Maritime University, Dalian, Liaoning 116026; Liu, Yu
2012-01-15
Graphical abstract: In this paper, spindle-like CaWO{sub 4}:Sm{sup 3+} phosphors were prepared via a polyvinylpyrrolidone (PVP)-assisted sonochemical process. Dependence of emission intensity on Sm{sup 3+} ions concentration in the CaWO{sub 4}:Sm{sup 3+} phosphor were also calculated via a nonlinear fitting by using the formula y = ax/(1 + bx{sup c}). Highlights: Black-Right-Pointing-Pointer The samples were prepared via a PVP assisted sonochemical process. Black-Right-Pointing-Pointer The color coordinates for 1 mol% Sm{sup 3+} doped CaWO{sub 4} phosphor were calculated. Black-Right-Pointing-Pointer The D-D interaction is responsible for concentration quenching between Sm{sup 3+} ions. Black-Right-Pointing-Pointer The critical energy transfer distances (R{sub c}) were obtained.more » -- Abstract: Spindle-like CaWO{sub 4}:Sm{sup 3+} phosphors were prepared via a Polyvinylpyrrolidone (PVP)-assisted sonochemical process, and characterized by using X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM) and photoluminescence spectroscopy (PL). The XRD results suggested that the prepared samples are single-phase. The FE-SEM images indicated that the prepared CaWO{sub 4}:Sm{sup 3+} phosphors are composed of many spindles with maximum average diameter of 150 nm and maximum average length of 500 nm. Under 404 nm excitation, the characteristic emissions corresponding to {sup 4}G{sub 5/2} {yields} {sup 6}H{sub J} (J = 5/2, 7/2, 9/2 and 11/2) transitions of Sm{sup 3+} in CaWO{sub 4} phosphors were observed. The color coordinates for 1 mol% Sm{sup 3+} doped CaWO{sub 4} phosphor were calculated to be (0.595, 0.404). The fluorescent concentration quenching of Sm{sup 3+} doped spindle-like phosphors was studied based on the Van Uitert's model, and it was found that the electric dipole-dipole (D-D) interaction is the dominant energy transfer mechanism between Sm{sup 3+} ions in the CaWO{sub 4}:Sm{sup 3+} phosphors. The critical energy transfer distance was estimated.« less
[Basic concept in computer assisted surgery].
Merloz, Philippe; Wu, Hao
2006-03-01
To investigate application of medical digital imaging systems and computer technologies in orthopedics. The main computer-assisted surgery systems comprise the four following subcategories. (1) A collection and recording process for digital data on each patient, including preoperative images (CT scans, MRI, standard X-rays), intraoperative visualization (fluoroscopy, ultrasound), and intraoperative position and orientation of surgical instruments or bone sections (using 3D localises). Data merging based on the matching of preoperative imaging (CT scans, MRI, standard X-rays) and intraoperative visualization (anatomical landmarks, or bone surfaces digitized intraoperatively via 3D localiser; intraoperative ultrasound images processed for delineation of bone contours). (2) In cases where only intraoperative images are used for computer-assisted surgical navigation, the calibration of the intraoperative imaging system replaces the merged data system, which is then no longer necessary. (3) A system that provides aid in decision-making, so that the surgical approach is planned on basis of multimodal information: the interactive positioning of surgical instruments or bone sections transmitted via pre- or intraoperative images, display of elements to guide surgical navigation (direction, axis, orientation, length and diameter of a surgical instrument, impingement, etc. ). And (4) A system that monitors the surgical procedure, thereby ensuring that the optimal strategy defined at the preoperative stage is taken into account. It is possible that computer-assisted orthopedic surgery systems will enable surgeons to better assess the accuracy and reliability of the various operative techniques, an indispensable stage in the optimization of surgery.
Three-dimensional spatiotemporal features for fast content-based retrieval of focal liver lesions.
Roy, Sharmili; Chi, Yanling; Liu, Jimin; Venkatesh, Sudhakar K; Brown, Michael S
2014-11-01
Content-based image retrieval systems for 3-D medical datasets still largely rely on 2-D image-based features extracted from a few representative slices of the image stack. Most 2 -D features that are currently used in the literature not only model a 3-D tumor incompletely but are also highly expensive in terms of computation time, especially for high-resolution datasets. Radiologist-specified semantic labels are sometimes used along with image-based 2-D features to improve the retrieval performance. Since radiological labels show large interuser variability, are often unstructured, and require user interaction, their use as lesion characterizing features is highly subjective, tedious, and slow. In this paper, we propose a 3-D image-based spatiotemporal feature extraction framework for fast content-based retrieval of focal liver lesions. All the features are computer generated and are extracted from four-phase abdominal CT images. Retrieval performance and query processing times for the proposed framework is evaluated on a database of 44 hepatic lesions comprising of five pathological types. Bull's eye percentage score above 85% is achieved for three out of the five lesion pathologies and for 98% of query lesions, at least one same type of lesion is ranked among the top two retrieved results. Experiments show that the proposed system's query processing is more than 20 times faster than other already published systems that use 2-D features. With fast computation time and high retrieval accuracy, the proposed system has the potential to be used as an assistant to radiologists for routine hepatic tumor diagnosis.
3-D Technology Approaches for Biological Ecologies
NASA Astrophysics Data System (ADS)
Liu, Liyu; Austin, Robert; U. S-China Physical-Oncology Sciences Alliance (PS-OA) Team
Constructing three dimensional (3-D) landscapes is an inevitable issue in deep study of biological ecologies, because in whatever scales in nature, all of the ecosystems are composed by complex 3-D environments and biological behaviors. Just imagine if a 3-D technology could help complex ecosystems be built easily and mimic in vivo microenvironment realistically with flexible environmental controls, it will be a fantastic and powerful thrust to assist researchers for explorations. For years, we have been utilizing and developing different technologies for constructing 3-D micro landscapes for biophysics studies in in vitro. Here, I will review our past efforts, including probing cancer cell invasiveness with 3-D silicon based Tepuis, constructing 3-D microenvironment for cell invasion and metastasis through polydimethylsiloxane (PDMS) soft lithography, as well as explorations of optimized stenting positions for coronary bifurcation disease with 3-D wax printing and the latest home designed 3-D bio-printer. Although 3-D technologies is currently considered not mature enough for arbitrary 3-D micro-ecological models with easy design and fabrication, I hope through my talk, the audiences will be able to sense its significance and predictable breakthroughs in the near future. This work was supported by the State Key Development Program for Basic Research of China (Grant No. 2013CB837200), the National Natural Science Foundation of China (Grant No. 11474345) and the Beijing Natural Science Foundation (Grant No. 7154221).
Abe, Yuichiro; Ito, Manabu; Abumi, Kuniyoshi; Kotani, Yoshihisa; Sudo, Hideki; Minami, Akio
2011-11-01
Use of computer-assisted spine surgery (CASS) technologies, such as navigation systems, to improve the accuracy of pedicle screw (PS) placement is increasingly popular. Despite of their benefits, previous CASS systems are too expensive to be ubiquitously employed, and more affordable and portable systems are desirable. The aim of this study was to introduce a novel and affordable computer-assisted technique that 3-dimensionally visualizes anatomical features of the pedicles and assists in PS insertion. The authors have termed this the 3D-visual guidance technique for inserting pedicle screws (3D-VG TIPS). The 3D-VG technique for placing PSs requires only a consumer-class computer with an inexpensive 3D DICOM viewer; other special equipment is unnecessary. Preoperative CT data of the spine were collected for each patient using the 3D-VG TIPS. In this technique, the anatomical axis of each pedicle can be analyzed by volume-rendered 3D models, as with existing navigation systems, and both the ideal entry point and the trajectory of each PS can be visualized on the surface of 3D-rendered images. Intraoperative guidance slides are made from these images and displayed on a TV monitor in the operating room. The surgeon can insert PSs according to these guidance slides. The authors enrolled 30 patients with adolescent idiopathic scoliosis (AIS) who underwent posterior fusion with segmental screw fixation for validation of this technique. The novel technique allowed surgeons, from office or home, to evaluate the precise anatomy of each pedicle and the risks of screw misplacement, and to perform 3D preoperative planning for screw placement on their own computer. Looking at both 3D guidance images on a TV monitor and the bony structures of the posterior elements in each patient in the operating theater, surgeons were able to determine the best entry point for each PS with ease and confidence. Using the current technique, the screw malposition rate was 4.5% in the thoracic region in corrective surgery for AIS. The authors found that 3D-VG TIPS worked on a consumer-class computer and easily visualized the ideal entry point and trajectory of PSs in any operating theater without costly special equipment. This new technique is suitable for preoperative planning and intraoperative guidance when performing reconstructive surgery with PSs.
Ripley, Beth; Kelil, Tatiana; Cheezum, Michael K.; Goncalves, Alexandra; Di Carli, Marcelo F.; Rybicki, Frank J.; Steigner, Mike; Mitsouras, Dimitrios; Blankstein, Ron
2017-01-01
Background 3D printing is a promising technique that may have applications in medicine, and there is expanding interest in the use of patient-specific 3D models to guide surgical interventions. Objective To determine the feasibility of using cardiac CT to print individual models of the aortic root complex for transcatheter aortic valve replacement (TAVR) planning as well as to determine the ability to predict paravalvular aortic regurgitation (PAR). Methods This retrospective study included 16 patients (9 with PAR identified on blinded interpretation of post-procedure trans-thoracic echocardiography and 7 age, sex, and valve size-matched controls with no PAR). 3D printed models of the aortic root were created from pre-TAVR cardiac computed tomography data. These models were fitted with printed valves and predictions regarding post-implant PAR were made using a light transmission test. Results Aortic root 3D models were highly accurate, with excellent agreement between annulus measurements made on 3D models and those made on corresponding 2D data (mean difference of −0.34 mm, 95% limits of agreement: ± 1.3 mm). The 3D printed valve models were within 0.1 mm of their designed dimensions. Examination of the fit of valves within patient-specific aortic root models correctly predicted PAR in 6 of 9 patients (6 true positive, 3 false negative) and absence of PAR in 5 of 7 patients (5 true negative, 2 false positive). Conclusions Pre-TAVR 3D-printing based on cardiac CT provides a unique patient-specific method to assess the physical interplay of the aortic root and implanted valves. With additional optimization, 3D models may complement traditional techniques used for predicting which patients are more likely to develop PAR. PMID:26732862
Yu, You; Yan, Casey; Zheng, Zijian
2014-08-20
Metal interconnects, contacts, and electrodes are indispensable elements for most applications of flexible, stretchable, and wearable electronics. Current fabrication methods for these metal conductors are mainly based on conventional microfabrication procedures that have been migrated from Si semiconductor industries, which face significant challenges for organic-based compliant substrates. This Research News highlights a recently developed full-solution processing strategy, polymer-assisted metal deposition (PAMD), which is particularly suitable for the roll-to-roll, low-cost fabrication of high-performance compliant metal conductors (Cu, Ni, Ag, and Au) on a wide variety of organic substrates including plastics, elastomers, papers, and textiles. This paper presents i) the principles of PAMD, and how to use it for making ii) flexible, stretchable, and wearable conductive metal electrodes, iii) patterned metal interconnects, and d) 3D stretchable and compressible metal sponges. A critical perspective on this emerging strategy is also provided. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Liluashvili, Vaja; Kalayci, Selim; Fluder, Eugene; Wilson, Manda; Gabow, Aaron
2017-01-01
Abstract Visualizations of biomolecular networks assist in systems-level data exploration in many cellular processes. Data generated from high-throughput experiments increasingly inform these networks, yet current tools do not adequately scale with concomitant increase in their size and complexity. We present an open source software platform, interactome-CAVE (iCAVE), for visualizing large and complex biomolecular interaction networks in 3D. Users can explore networks (i) in 3D using a desktop, (ii) in stereoscopic 3D using 3D-vision glasses and a desktop, or (iii) in immersive 3D within a CAVE environment. iCAVE introduces 3D extensions of known 2D network layout, clustering, and edge-bundling algorithms, as well as new 3D network layout algorithms. Furthermore, users can simultaneously query several built-in databases within iCAVE for network generation or visualize their own networks (e.g., disease, drug, protein, metabolite). iCAVE has modular structure that allows rapid development by addition of algorithms, datasets, or features without affecting other parts of the code. Overall, iCAVE is the first freely available open source tool that enables 3D (optionally stereoscopic or immersive) visualizations of complex, dense, or multi-layered biomolecular networks. While primarily designed for researchers utilizing biomolecular networks, iCAVE can assist researchers in any field. PMID:28814063
Liluashvili, Vaja; Kalayci, Selim; Fluder, Eugene; Wilson, Manda; Gabow, Aaron; Gümüs, Zeynep H
2017-08-01
Visualizations of biomolecular networks assist in systems-level data exploration in many cellular processes. Data generated from high-throughput experiments increasingly inform these networks, yet current tools do not adequately scale with concomitant increase in their size and complexity. We present an open source software platform, interactome-CAVE (iCAVE), for visualizing large and complex biomolecular interaction networks in 3D. Users can explore networks (i) in 3D using a desktop, (ii) in stereoscopic 3D using 3D-vision glasses and a desktop, or (iii) in immersive 3D within a CAVE environment. iCAVE introduces 3D extensions of known 2D network layout, clustering, and edge-bundling algorithms, as well as new 3D network layout algorithms. Furthermore, users can simultaneously query several built-in databases within iCAVE for network generation or visualize their own networks (e.g., disease, drug, protein, metabolite). iCAVE has modular structure that allows rapid development by addition of algorithms, datasets, or features without affecting other parts of the code. Overall, iCAVE is the first freely available open source tool that enables 3D (optionally stereoscopic or immersive) visualizations of complex, dense, or multi-layered biomolecular networks. While primarily designed for researchers utilizing biomolecular networks, iCAVE can assist researchers in any field. © The Authors 2017. Published by Oxford University Press.
Er 3+-Yb 3+ co-doped glass waveguide amplifiers using ion exchange and field-assisted annealing
NASA Astrophysics Data System (ADS)
Zhang, X. Z.; Liu, K.; Mu, S. K.; Tan, C. Z.; Zhang, D.; Pun, E. Y. B.; Zhang, D. M.
2006-12-01
Er 3+-Yb 3+ co-doped waveguide amplifiers fabricated using thermal two-step ion-exchange are demonstrated. K +-Na + ion-exchange process was first carried out in pure KNO 3 molten bath, and then field-assisted annealing (FAA) was used to make the buried waveguides. The effective buried depth is estimated to be ˜3.4 μm for the buried FAA waveguides. With the use of cut-back method, the fiber-to-guide coupling loss of ˜4.38 dB, the waveguide loss of ˜2.27 dB/cm, and Er 3+ absorption loss ˜5.7 dB were measured for a ˜1.24-cm-long waveguide. Peak relative gain of ˜7.0 dB is obtained for a ˜1.24-cm-long waveguide. The potential for the fabrication of compact optical amplifiers operating in the range of 1520-1580 nm is also demonstrated.
Chen, Hui; Lowe, Alan A; de Almeida, Fernanda Riberiro; Wong, Mary; Fleetham, John A; Wang, Bangkang
2008-09-01
The aim of this study was to test a 3-dimensional (3D) computer-assisted dental model analysis system that uses selected landmarks to describe tooth movement during treatment with an oral appliance. Dental casts of 70 patients diagnosed with obstructive sleep apnea and treated with oral appliances for a mean time of 7 years 4 months were evaluated with a 3D digitizer (MicroScribe-3DX, Immersion, San Jose, Calif) compatible with the Rhinoceros modeling program (version 3.0 SR3c, Robert McNeel & Associates, Seattle, Wash). A total of 86 landmarks on each model were digitized, and 156 variables were calculated as either the linear distance between points or the distance from points to reference planes. Four study models for each patient (maxillary baseline, mandibular baseline, maxillary follow-up, and mandibular follow-up) were superimposed on 2 sets of reference points: 3 points on the palatal rugae for maxillary model superimposition, and 3 occlusal contact points for the same set of maxillary and mandibular model superimpositions. The patients were divided into 3 evaluation groups by 5 orthodontists based on the changes between baseline and follow-up study models. Digital dental measurements could be analyzed, including arch width, arch length, curve of Spee, overbite, overjet, and the anteroposterior relationship between the maxillary and mandibular arches. A method error within 0.23 mm in 14 selected variables was found for the 3D system. The statistical differences in the 3 evaluation groups verified the division criteria determined by the orthodontists. The system provides a method to record 3D measurements of study models that permits computer visualization of tooth position and movement from various perspectives.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wang, Ruixue; Yang, Bin, E-mail: binyang@hit.edu.cn; Sun, Enwei
The crystalline phases and domain configuration in the morphotropic phase boundary composition Pb(Mg{sub 1/3}Nb{sub 2/3})O{sub 3}-0.34PbTiO{sub 3} (PMN-0.34PT) single crystal have been investigated by synchrotron-based X-ray 3D Reciprocal Space Mapping (3D-RSM) and Piezoresponse Force Microscopy. The coexistence of tetragonal (T) and monoclinic M{sub C} phases in this PMN-0.34PT single crystal is confirmed. The affiliation of each diffraction spot in the 3D-RSM was identified with the assistance of qualitative simulation. Most importantly, the twinning structure between different domains in such a mixed phase PMN-PT crystal is firmly clarified, and the spatial distribution of different twin domains is demonstrated. In addition, themore » lattice parameters of T and M{sub C} phases in PMN-0.34PT single crystal as well as the tilting angles of crystal lattices caused by the interfacial lattice mismatch are determined.« less
Balling, Horst
2018-05-01
Prospective single-center cohort study to record additional time requirements and radiation dose in navigation-assisted O-arm-controlled pedicle screw (PS) instrumentations. The aim of this study was to evaluate amount of extra-time and radiation dose for navigation-assisted PS instrumentations of the thoracolumbosacral spine using O-arm 3D-real-time-navigation (O3DN) compared to non-navigated spinal procedures (NNSPs) with a single C-arm and postoperative computed tomography (CT) scan for controlling PS positions. 3D-navigation is reported to enhance PS insertion accuracy. But time-consuming navigational steps and considerable additional radiation doses seem to limit this modern technique's attraction. A detailed analysis of additional time demand and extra-radiation dose in 3D-navigated spine surgery is not provided in literature, yet. From February 2011 through July 2015, 306 consecutive posterior instrumentations were performed in vertebral levels T10-S1 using O3DN for PS insertion. The duration of procedure-specific navigational steps of the overall collective (I) and the last cohort of 50 consecutive O3DN-surgeries (II) was compared to the average duration of analogous surgical steps in 100 consecutive NNSP using a single C-arm. 3D-radiation dose (dose-length-product, DLP) of navigational and postinstrumentation O-arm scans in group I and II was compared to the average DLP of 100 diagnostic lumbar CT scans. The average presurgical time from patient positioning on the operating table to skin incision was 46.2 ± 10.1 minutes (O3DN, I) and 40.6 ± 9.8 minutes (O3DN, II) versus 30.6 ± 8.3 minutes (NNSP) (P < 0.001, each). Intraoperative interruptions for scanning and data processing took 3.0 ± 0.6 minutes. DLPs averaged 865.1 ± 360.8 mGycm (O3DN, I) and 562.1 ± 352.6 mGycm (O3DN, II) compared to 575.5 ± 316.5 mGycm in diagnostic lumbar CT scans (P < 0.001 (I), P ≈ 0.81 [II]). After procedural experience, navigated surgeries can be performed with an additional time demand of 13.0 minutes compared to NNSP, and with a total DLP below that of a diagnostic lumbar CT scan (P ≈ 0.81). 4.
Numerical, analytical, experimental study of fluid dynamic forces in seals
NASA Technical Reports Server (NTRS)
Shapiro, William; Artiles, Antonio; Aggarwal, Bharat; Walowit, Jed; Athavale, Mahesh M.; Preskwas, Andrzej J.
1992-01-01
NASA/Lewis Research Center is sponsoring a program for providing computer codes for analyzing and designing turbomachinery seals for future aerospace and engine systems. The program is made up of three principal components: (1) the development of advanced three dimensional (3-D) computational fluid dynamics codes, (2) the production of simpler two dimensional (2-D) industrial codes, and (3) the development of a knowledge based system (KBS) that contains an expert system to assist in seal selection and design. The first task has been to concentrate on cylindrical geometries with straight, tapered, and stepped bores. Improvements have been made by adoption of a colocated grid formulation, incorporation of higher order, time accurate schemes for transient analysis and high order discretization schemes for spatial derivatives. This report describes the mathematical formulations and presents a variety of 2-D results, including labyrinth and brush seal flows. Extensions of 3-D are presently in progress.
Generic Dynamic Environment Perception Using Smart Mobile Devices.
Danescu, Radu; Itu, Razvan; Petrovai, Andra
2016-10-17
The driving environment is complex and dynamic, and the attention of the driver is continuously challenged, therefore computer based assistance achieved by processing image and sensor data may increase traffic safety. While active sensors and stereovision have the advantage of obtaining 3D data directly, monocular vision is easy to set up, and can benefit from the increasing computational power of smart mobile devices, and from the fact that almost all of them come with an embedded camera. Several driving assistance application are available for mobile devices, but they are mostly targeted for simple scenarios and a limited range of obstacle shapes and poses. This paper presents a technique for generic, shape independent real-time obstacle detection for mobile devices, based on a dynamic, free form 3D representation of the environment: the particle based occupancy grid. Images acquired in real time from the smart mobile device's camera are processed by removing the perspective effect and segmenting the resulted bird-eye view image to identify candidate obstacle areas, which are then used to update the occupancy grid. The occupancy grid tracked cells are grouped into obstacles depicted as cuboids having position, size, orientation and speed. The easy to set up system is able to reliably detect most obstacles in urban traffic, and its measurement accuracy is comparable to a stereovision system.
Yang, Long; Shang, Xian-Wen; Fan, Jian-Nan; He, Zhi-Xu; Wang, Jian-Ji; Liu, Miao; Zhuang, Yong; Ye, Chuan
2016-01-01
To evaluate the effect of 3D printing in treating trimalleolar fractures and its roles in physician-patient communication, thirty patients with trimalleolar fractures were randomly divided into the 3D printing assisted-design operation group (Group A) and the no-3D printing assisted-design group (Group B). In Group A, 3D printing was used by the surgeons to produce a prototype of the actual fracture to guide the surgical treatment. All patients underwent open reduction and internal fixation. A questionnaire was designed for doctors and patients to verify the verisimilitude and effectiveness of the 3D-printed prototype. Meanwhile, the operation time and the intraoperative blood loss were compared between the two groups. The fracture prototypes were accurately printed, and the average overall score of the verisimilitude and effectiveness of the 3D-printed prototypes was relatively high. Both the operation time and the intraoperative blood loss in Group A were less than those in Group B (P < 0.05). Patient satisfaction using the 3D-printed prototype and the communication score were 9.3 ± 0.6 points. A 3D-printed prototype can faithfully reflect the anatomy of the fracture site; it can effectively help the doctors plan the operation and represent an effective tool for physician-patient communication.
NASA Astrophysics Data System (ADS)
Zhang, Yu; Jin, Lei; Jiang, Dandan; Zou, Xingqi; Zhao, Zhiguo; Gao, Jing; Zeng, Ming; Zhou, Wenbin; Tang, Zhaoyun; Huo, Zongliang
2018-03-01
In order to optimize program disturbance characteristics effectively, a characterization approach that measures top select transistor (TSG) leakage from bit-line is proposed to quantify TSG leakage under program inhibit condition in 3D NAND flash memory. Based on this approach, the effect of Vth modulation of two-cell TSG on leakage is evaluated. By checking the dependence of leakage and corresponding program disturbance on upper and lower TSG Vth, this approach is validated. The optimal Vth pattern with high upper TSG Vth and low lower TSG Vth has been suggested for low leakage current and high boosted channel potential. It is found that upper TSG plays dominant role in preventing drain induced barrier lowering (DIBL) leakage from boosted channel to bit-line, while lower TSG assists to further suppress TSG leakage by providing smooth potential drop from dummy WL to edge of TSG, consequently suppressing trap assisted band-to-band tunneling current (BTBT) between dummy WL and TSG.
Stereo camera based virtual cane system with identifiable distance tactile feedback for the blind.
Kim, Donghun; Kim, Kwangtaek; Lee, Sangyoun
2014-06-13
In this paper, we propose a new haptic-assisted virtual cane system operated by a simple finger pointing gesture. The system is developed by two stages: development of visual information delivery assistant (VIDA) with a stereo camera and adding a tactile feedback interface with dual actuators for guidance and distance feedbacks. In the first stage, user's pointing finger is automatically detected using color and disparity data from stereo images and then a 3D pointing direction of the finger is estimated with its geometric and textural features. Finally, any object within the estimated pointing trajectory in 3D space is detected and the distance is then estimated in real time. For the second stage, identifiable tactile signals are designed through a series of identification experiments, and an identifiable tactile feedback interface is developed and integrated into the VIDA system. Our approach differs in that navigation guidance is provided by a simple finger pointing gesture and tactile distance feedbacks are perfectly identifiable to the blind.
Stereo Camera Based Virtual Cane System with Identifiable Distance Tactile Feedback for the Blind
Kim, Donghun; Kim, Kwangtaek; Lee, Sangyoun
2014-01-01
In this paper, we propose a new haptic-assisted virtual cane system operated by a simple finger pointing gesture. The system is developed by two stages: development of visual information delivery assistant (VIDA) with a stereo camera and adding a tactile feedback interface with dual actuators for guidance and distance feedbacks. In the first stage, user's pointing finger is automatically detected using color and disparity data from stereo images and then a 3D pointing direction of the finger is estimated with its geometric and textural features. Finally, any object within the estimated pointing trajectory in 3D space is detected and the distance is then estimated in real time. For the second stage, identifiable tactile signals are designed through a series of identification experiments, and an identifiable tactile feedback interface is developed and integrated into the VIDA system. Our approach differs in that navigation guidance is provided by a simple finger pointing gesture and tactile distance feedbacks are perfectly identifiable to the blind. PMID:24932864
Sadasivan, Chander; Brownstein, Jeremy; Patel, Bhumika; Dholakia, Ronak; Santore, Joseph; Al-Mufti, Fawaz; Puig, Enrique; Rakian, Audrey; Fernandez-Prada, Kenneth D; Elhammady, Mohamed S; Farhat, Hamad; Fiorella, David J; Woo, Henry H; Aziz-Sultan, Mohammad A; Lieber, Baruch B
2013-03-01
Endovascular coiling of cerebral aneurysms remains limited by coil compaction and associated recanalization. Recent coil designs which effect higher packing densities may be far from optimal because hemodynamic forces causing compaction are not well understood since detailed data regarding the location and distribution of coil masses are unavailable. We present an in vitro methodology to characterize coil masses deployed within aneurysms by quantifying intra-aneurysmal void spaces. Eight identical aneurysms were packed with coils by both balloon- and stent-assist techniques. The samples were embedded, sequentially sectioned and imaged. Empty spaces between the coils were numerically filled with circles (2D) in the planar images and with spheres (3D) in the three-dimensional composite images. The 2D and 3D void size histograms were analyzed for local variations and by fitting theoretical probability distribution functions. Balloon-assist packing densities (31±2%) were lower ( p =0.04) than the stent-assist group (40±7%). The maximum and average 2D and 3D void sizes were higher ( p =0.03 to 0.05) in the balloon-assist group as compared to the stent-assist group. None of the void size histograms were normally distributed; theoretical probability distribution fits suggest that the histograms are most probably exponentially distributed with decay constants of 6-10 mm. Significant ( p <=0.001 to p =0.03) spatial trends were noted with the void sizes but correlation coefficients were generally low (absolute r <=0.35). The methodology we present can provide valuable input data for numerical calculations of hemodynamic forces impinging on intra-aneurysmal coil masses and be used to compare and optimize coil configurations as well as coiling techniques.
Synthesis of C-glycosyl-bis-1,2,3-triazole derivatives from 3,4,6-tri-O-acetyl-D-glucal.
Shamim, Anwar; Souza, Frederico B; Trossini, Gustavo H G; Gatti, Fernando M; Stefani, Hélio A
2015-08-01
We have developed an efficient, CuI-catalyzed, microwave-assisted method for the synthesis of bis-1,2,3-triazole derivatives starting from a 3,4,6-tri-O-acetyl-D-glucal-derived mesylate. This mesylate was obtained from 3,4,6-tri-O-acetyl-D-glucal through C-glycosidation, deprotection of acetate groups to alcohols, and selective mesylation of the primary alcohol. This mesylate moiety was then converted to an azide through a microwave-assisted method with good yield. The azide, once synthesized, was then treated with different terminal alkynes in the presence of CuI to synthesize various bis-triazoles in high yields and short reaction times.
Song, Wei-Li; Zhou, Zhili; Wang, Li-Chen; Cheng, Xiao-Dong; Chen, Mingji; He, Rujie; Chen, Haosen; Yang, Yazheng; Fang, Daining
2017-12-13
Ultra-broad-band electromagnetic absorption materials and structures are increasingly attractive for their critical role in competing with the advanced broad-band electromagnetic detection systems. Mechanically soft and weak wax-based materials composites are known to be insufficient to serve in practical electromagnetic absorption applications. To break through such barriers, here we developed an innovative strategy to enable the wax-based composites to be robust and repairable meta-structures by employing a three-dimensional (3D) printed polymeric patterned shell. Because of the integrated merits from both the dielectric loss wax-based composites and mechanically robust 3D printed shells, the as-fabricated meta-structures enable bear mechanical collision and compression, coupled with ultra-broad-band absorption (7-40 and 75-110 GHz, reflection loss smaller than -10 dB) approaching state-of-the-art electromagnetic absorption materials. With the assistance of experiment and simulation methods, the design advantages and mechanism of employing such 3D printed shells for substantially promoting the electromagnetic absorption performance have been demonstrated. Therefore, such universal strategy that could be widely extended to other categories of wax-based composites highlights a smart stage on which high-performance practical multifunction meta-structures with ultra-broad-band electromagnetic absorption could be envisaged.
One-Step Solvent Evaporation-Assisted 3D Printing of Piezoelectric PVDF Nanocomposite Structures.
Bodkhe, Sampada; Turcot, Gabrielle; Gosselin, Frederick P; Therriault, Daniel
2017-06-21
Development of a 3D printable material system possessing inherent piezoelectric properties to fabricate integrable sensors in a single-step printing process without poling is of importance to the creation of a wide variety of smart structures. Here, we study the effect of addition of barium titanate nanoparticles in nucleating piezoelectric β-polymorph in 3D printable polyvinylidene fluoride (PVDF) and fabrication of the layer-by-layer and self-supporting piezoelectric structures on a micro- to millimeter scale by solvent evaporation-assisted 3D printing at room temperature. The nanocomposite formulation obtained after a comprehensive investigation of composition and processing techniques possesses a piezoelectric coefficient, d 31 , of 18 pC N -1 , which is comparable to that of typical poled and stretched commercial PVDF film sensors. A 3D contact sensor that generates up to 4 V upon gentle finger taps demonstrates the efficacy of the fabrication technique. Our one-step 3D printing of piezoelectric nanocomposites can form ready-to-use, complex-shaped, flexible, and lightweight piezoelectric devices. When combined with other 3D printable materials, they could serve as stand-alone or embedded sensors in aerospace, biomedicine, and robotic applications.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Abdel-Khalik, Jonas, E-mail: J.A.F.A.ABDEL-KHALIK.744116@swansea.ac.uk; Crick, Peter J.; Carter, Graham D.
2014-04-11
Highlights: • New method for the analysis of 25-hydroxyvitamin D{sub 3} exploiting Girard P derivatisation. • Method also applicable to vitamin D{sub 3}, 1α,25- and 24,25-dihydroxyvitamin D{sub 3}. • By modification of the method 3-epi-25-hydroxyvitamin D{sub 3} can also be analysed. - Abstract: The total serum concentration of 25-hydroxyvitamins D (25-hydroxyvitamin D{sub 3} and 25-hydroxyvitamin D{sub 2}) is currently used as an indicator of vitamins D status. Vitamins D insufficiency is claimed to be associated with multiple diseases, thus accurate and precise reference methods for the quantification of 25-hydroxyvitamins D are needed. Here we present a novel enzyme-assisted derivatisation methodmore » for the analysis of vitamins D metabolites in adult serum utilising 25-[26,26,26,27,27,27-{sup 2}H{sub 6}]hydroxyvitamin D{sub 3} as the internal standard. Extraction of 25-hydroxyvitamins D from serum is performed with acetonitrile, which is shown to be more efficient than ethanol. Cholesterol oxidase is used to oxidize the 3β-hydroxy group in the vitamins D metabolites followed by derivatisation of the newly formed 3-oxo group with Girard P reagent. 17β-Hydroxysteroid dehydrogenase type 10 is shown to oxidize selectively the 3α-hydroxy group in the 3α-hydroxy epimer of 25-hydroxyvitamin D{sub 3}. Quantification is achieved by isotope-dilution liquid chromatography–tandem mass spectrometry. Recovery experiments for 25-hydroxyvitamin D{sub 3} performed on adult human serum give recovery of 102–106%. Furthermore in addition to 25-hydroxyvitamin D{sub 3}, 24,25-dihydroxyvitamin D{sub 3} and other uncharacterised dihydroxy metabolites, were detected in adult human serum.« less
Zhang, Wang; Qiu, Ling-Guang; Yuan, Yu-Peng; Xie, An-Jian; Shen, Yu-Hua; Zhu, Jun-Fa
2012-06-30
Covalent organic frameworks (COFs) are a new generation of porous materials constructed from light elements linked by strong covalent bonds. Herein we present rapid preparation of highly fluorescent nanoparticles of a new type of COF, i.e. melamine-based porous polymeric network SNW-1, by a microwave-assisted synthesis route. Although the synthesis of SNW-1 has to be carried out at 180°C for 3d under conventional reflux conditions, SNW-1 nanoparticles could be obtained in 6h by using such a microwave-assisted method. The results obtained have clearly demonstrated that microwave-assisted synthesis is a simple yet highly efficient approach to nanoscale COFs or other porous polymeric materials. Remarkably, the as-synthesized SNW-1 nanoparticles exhibit extremely high sensitivity and selectivity, as well as fast response to nitroaromatic explosives such as 2,4,6-trinitrotoluene (TNT), 2,4,6-trinitrophenylmethylnitramine (Tetryl) and picric acid (PA) without interference by common organic solvents, which is due to the nanoscaled size and unique hierarchical porosity of such fluorescence-based sensing material. Copyright © 2012 Elsevier B.V. All rights reserved.
Qian, Dan; Zhang, Anfeng; Zhu, Jianxue; ...
2016-09-09
Here in this letter, microstructural and mechanical inhomogeneities, a great concern for single crystal Ni-based superalloys repaired by laser assisted 3D printing, have been probed near the epitaxial interface. Nanoindentation tests show the hardness to be uniformly lower in the bulk of the substrate and constantly higher in the epitaxial cladding layer. A gradient of hardness through the heat affected zone is also observed, resulting from an increase in dislocation density, as indicated by the broadening of the synchrotron X-ray Laue microdiffraction reflections. Lastly, the hardening mechanism of the claddin g region, on the other hand, is shown to originatemore » not only from high dislocation density but also and more importantly from the fine γ/γ' microstructure.« less
NASA Astrophysics Data System (ADS)
Lin, Pei-Chun; Yu, Chun-Chang; Chen, Charlie Chung-Ping
2015-01-01
As one of the critical stages of a very large scale integration fabrication process, postexposure bake (PEB) plays a crucial role in determining the final three-dimensional (3-D) profiles and lessening the standing wave effects. However, the full 3-D chemically amplified resist simulation is not widely adopted during the postlayout optimization due to the long run-time and huge memory usage. An efficient simulation method is proposed to simulate the PEB while considering standing wave effects and resolution enhancement techniques, such as source mask optimization and subresolution assist features based on the Sylvester equation and Abbe-principal component analysis method. Simulation results show that our algorithm is 20× faster than the conventional Gaussian convolution method.
Graphene-assisted multiple-input high-base optical computing
Hu, Xiao; Wang, Andong; Zeng, Mengqi; Long, Yun; Zhu, Long; Fu, Lei; Wang, Jian
2016-01-01
We propose graphene-assisted multiple-input high-base optical computing. We fabricate a nonlinear optical device based on a fiber pigtail cross-section coated with a single-layer graphene grown by chemical vapor deposition (CVD) method. An approach to implementing modulo 4 operations of three-input hybrid addition and subtraction of quaternary base numbers in the optical domain using multiple non-degenerate four-wave mixing (FWM) processes in graphene coated optical fiber device and (differential) quadrature phase-shift keying ((D)QPSK) signals is presented. We demonstrate 10-Gbaud modulo 4 operations of three-input quaternary hybrid addition and subtraction (A + B − C, A + C − B, B + C − A) in the experiment. The measured optical signal-to-noise ratio (OSNR) penalties for modulo 4 operations of three-input quaternary hybrid addition and subtraction (A + B − C, A + C − B, B + C − A) are measured to be less than 7 dB at a bit-error rate (BER) of 2 × 10−3. The BER performance as a function of the relative time offset between three signals (signal offset) is also evaluated showing favorable performance. PMID:27604866
Lessons From Bosnia: The IFOR Experience
1998-01-01
OSD under the direc- tion of ASD (C3I). DoD Command and Control Research Program Assistant Secretary of Defense (C3I) Mr. Anthony Valletta (Acting...Anthony M. Valletta (Acting) Assistant Secretary of Defense C3I xiii Acknowledgments The Honorable Emmett Paige, Jr., Assistant Secretary of Defense... Valletta ; and the Di- rectors J6, the Joint Staff, Admiral Walt Cebrowski, USN, and LTG Doug Buchholz, USA, for their continued interest and support
PC software package to confront multimodality images and a stereotactic atlas in neurosurgery
NASA Astrophysics Data System (ADS)
Barillot, Christian; Lemoine, Didier; Gibaud, Bernard; Toulemont, P. J.; Scarabin, Jean-Marie
1990-07-01
The aim of this application is to interactively transfer information between CT, MRI or DSA data and a 3D stereotactic atlas digitized on a C. Based on a 3D organization of data, this system is devoted to assist a neurosurgeon in surgical planning by numerically cross-assigning information between heterogeneous data (in-vivo or atlas). All these images can be retrieved in digital form from the PACS central archive (SIRENE PACS system). The basic feature of this confrontation is the Talairach's proportional squaring which consists in dividing the 3D cerebral space in independently deformable sub-parts. This 3D model is based on anatomical structures such as the AC-PC line and its two associated vertical lines VAC and VPC. Based on this proportional squaring, the atlas has been digitized in order to get atlas plates along the three orthogonal directions of this geometrical reference (axial, coronal, sagittal). The registration of in-vivo data to the proportional squaring is done by extracting either external framework landmarks or anatomical reference structures (i.e. AC and PC structures on the MRI sagittal mid-plane image). Geometrical transformations and scaling are then recorded for each modality or acquisition according to the proportional squaring. These transformations make for instance possible the transfer of a 3D point of a MRI examination to its 3D location within the proportional squaring and furthermore to its 3D location within another data set (in-vivo or atlas). From that stage, the application gives the choice to the neurosurgeon to select any confrontation between input data (in-vivo images or atlas) and output data (id).
NASA Astrophysics Data System (ADS)
Rodgers, J.; Tessier, D.; D'Souza, D.; Leung, E.; Hajdok, G.; Fenster, A.
2016-04-01
High-dose-rate (HDR) interstitial brachytherapy is often included in standard-of-care for gynaecological cancers. Needles are currently inserted through a perineal template without any standard real-time imaging modality to assist needle guidance, causing physicians to rely on pre-operative imaging, clinical examination, and experience. While two-dimensional (2D) ultrasound (US) is sometimes used for real-time guidance, visualization of needle placement and depth is difficult and subject to variability and inaccuracy in 2D images. The close proximity to critical organs, in particular the rectum and bladder, can lead to serious complications. We have developed a three-dimensional (3D) transrectal US system and are investigating its use for intra-operative visualization of needle positions used in HDR gynaecological brachytherapy. As a proof-of-concept, four patients were imaged with post-insertion 3D US and x-ray CT. Using software developed in our laboratory, manual rigid registration of the two modalities was performed based on the perineal template's vaginal cylinder. The needle tip and a second point along the needle path were identified for each needle visible in US. The difference between modalities in the needle trajectory and needle tip position was calculated for each identified needle. For the 60 needles placed, the mean trajectory difference was 3.23 +/- 1.65° across the 53 visible needle paths and the mean difference in needle tip position was 3.89 +/- 1.92 mm across the 48 visible needles tips. Based on the preliminary results, 3D transrectal US shows potential for the development of a 3D US-based needle guidance system for interstitial gynaecological brachytherapy.
Development of a precision multimodal surgical navigation system for lung robotic segmentectomy
Soldea, Valentin; Lachkar, Samy; Rinieri, Philippe; Sarsam, Mathieu; Bottet, Benjamin; Peillon, Christophe
2018-01-01
Minimally invasive sublobar anatomical resection is becoming more and more popular to manage early lung lesions. Robotic-assisted thoracic surgery (RATS) is unique in comparison with other minimally invasive techniques. Indeed, RATS is able to better integrate multiple streams of information including advanced imaging techniques, in an immersive experience at the level of the robotic console. Our aim was to describe three-dimensional (3D) imaging throughout the surgical procedure from preoperative planning to intraoperative assistance and complementary investigations such as radial endobronchial ultrasound (R-EBUS) and virtual bronchoscopy for pleural dye marking. All cases were operated using the DaVinci SystemTM. Modelisation was provided by Visible Patient™ (Strasbourg, France). Image integration in the operative field was achieved using the Tile Pro multi display input of the DaVinci console. Our experience was based on 114 robotic segmentectomies performed between January 2012 and October 2017. The clinical value of 3D imaging integration was evaluated in 2014 in a pilot study. Progressively, we have reached the conclusion that the use of such an anatomic model improves the safety and reliability of procedures. The multimodal system including 3D imaging has been used in more than 40 patients so far and demonstrated a perfect operative anatomic accuracy. Currently, we are developing an original virtual reality experience by exploring 3D imaging models at the robotic console level. The act of operating is being transformed and the surgeon now oversees a complex system that improves decision making. PMID:29785294
Development of a precision multimodal surgical navigation system for lung robotic segmentectomy.
Baste, Jean Marc; Soldea, Valentin; Lachkar, Samy; Rinieri, Philippe; Sarsam, Mathieu; Bottet, Benjamin; Peillon, Christophe
2018-04-01
Minimally invasive sublobar anatomical resection is becoming more and more popular to manage early lung lesions. Robotic-assisted thoracic surgery (RATS) is unique in comparison with other minimally invasive techniques. Indeed, RATS is able to better integrate multiple streams of information including advanced imaging techniques, in an immersive experience at the level of the robotic console. Our aim was to describe three-dimensional (3D) imaging throughout the surgical procedure from preoperative planning to intraoperative assistance and complementary investigations such as radial endobronchial ultrasound (R-EBUS) and virtual bronchoscopy for pleural dye marking. All cases were operated using the DaVinci System TM . Modelisation was provided by Visible Patient™ (Strasbourg, France). Image integration in the operative field was achieved using the Tile Pro multi display input of the DaVinci console. Our experience was based on 114 robotic segmentectomies performed between January 2012 and October 2017. The clinical value of 3D imaging integration was evaluated in 2014 in a pilot study. Progressively, we have reached the conclusion that the use of such an anatomic model improves the safety and reliability of procedures. The multimodal system including 3D imaging has been used in more than 40 patients so far and demonstrated a perfect operative anatomic accuracy. Currently, we are developing an original virtual reality experience by exploring 3D imaging models at the robotic console level. The act of operating is being transformed and the surgeon now oversees a complex system that improves decision making.
Feng, Zhi-hong; Dong, Yan; Bai, Shi-zhu; Wu, Guo-feng; Bi, Yun-peng; Wang, Bo; Zhao, Yi-min
2010-01-01
The aim of this article was to demonstrate a novel approach to designing facial prostheses using the transplantation concept and computer-assisted technology for extensive, large, maxillofacial defects that cross the facial midline. The three-dimensional (3D) facial surface images of a patient and his relative were reconstructed using data obtained through optical scanning. Based on these images, the corresponding portion of the relative's face was transplanted to the patient's where the defect was located, which could not be rehabilitated using mirror projection, to design the virtual facial prosthesis without the eye. A 3D model of an artificial eye that mimicked the patient's remaining one was developed, transplanted, and fit onto the virtual prosthesis. A personalized retention structure for the artificial eye was designed on the virtual facial prosthesis. The wax prosthesis was manufactured through rapid prototyping, and the definitive silicone prosthesis was completed. The size, shape, and cosmetic appearance of the prosthesis were satisfactory and matched the defect area well. The patient's facial appearance was recovered perfectly with the prosthesis, as determined through clinical evaluation. The optical 3D imaging and computer-aided design/computer-assisted manufacturing system used in this study can design and fabricate facial prostheses more precisely than conventional manual sculpturing techniques. The discomfort generally associated with such conventional methods was decreased greatly. The virtual transplantation used to design the facial prosthesis for the maxillofacial defect, which crossed the facial midline, and the development of the retention structure for the eye were both feasible.
Stereoscopic vascular models of the head and neck: A computed tomography angiography visualization.
Cui, Dongmei; Lynch, James C; Smith, Andrew D; Wilson, Timothy D; Lehman, Michael N
2016-01-01
Computer-assisted 3D models are used in some medical and allied health science schools; however, they are often limited to online use and 2D flat screen-based imaging. Few schools take advantage of 3D stereoscopic learning tools in anatomy education and clinically relevant anatomical variations when teaching anatomy. A new approach to teaching anatomy includes use of computed tomography angiography (CTA) images of the head and neck to create clinically relevant 3D stereoscopic virtual models. These high resolution images of the arteries can be used in unique and innovative ways to create 3D virtual models of the vasculature as a tool for teaching anatomy. Blood vessel 3D models are presented stereoscopically in a virtual reality environment, can be rotated 360° in all axes, and magnified according to need. In addition, flexible views of internal structures are possible. Images are displayed in a stereoscopic mode, and students view images in a small theater-like classroom while wearing polarized 3D glasses. Reconstructed 3D models enable students to visualize vascular structures with clinically relevant anatomical variations in the head and neck and appreciate spatial relationships among the blood vessels, the skull and the skin. © 2015 American Association of Anatomists.
24 CFR 586.45 - Disposal of buildings and property.
Code of Federal Regulations, 2010 CFR
2010-04-01
... 24 Housing and Urban Development 3 2010-04-01 2010-04-01 false Disposal of buildings and property... ASSISTANCE-COMMUNITY REDEVELOPMENT AND HOMELESS ASSISTANCE § 586.45 Disposal of buildings and property. (a... from HUD under § 586.35(c)(1) or § 586.35(d)(2), DoD shall dispose of buildings and property in...
Han, Ding-Pei; Lu, Ai-Guo; Feng, Hao; Wang, Pu-Xiong-Zhi; Cao, Qi-Feng; Zong, Ya-Ping; Feng, Bo; Zheng, Min-Hua
2013-05-01
To study the feasibility, safety, and short-/long-term outcomes of laparoscopy-assisted right hemicolectomy with D3 lymphadenectomy for colon cancer. The clinical data of 177 cases that underwent laparoscopy-assisted radical right hemicolectomy with D3 lymphadenectomy for colon cancer between Jun 2003 and Sep 2010 was collected; the safety of operation, status of recovery, complication, oncological outcomes, and results of short-/long-term follow-up were analyzed. No case died in this study; five cases (2.82 %) were converted to open surgery. Four cases (2.26 %) underwent hand-assisted laparoscopic right hemicolectomy. The average operation time was 133 ± 36 min, and the blood loss was 94 ± 34 ml. The average time for passage of flatus, liquid food eating, and hospitalization were 2.1 ± 0.7, 3.2 ± 0.5, and 10.4 ± 2.7 day, respectively. The total number of lymph nodes removed was 15.2 ± 10.1. Postoperative complications were observed in 23 of 177 patients (12.99 %). The median follow-up period was 54 months; port-site recurrence was observed in one patient; local recurrence was found in five cases (2.82 %); distant metastasis was found in 21 cases (11.86 %). The cumulative overall survival of all stages at 12, 36, 60, and 72 months was 97.18 %, 83.73 %, 70.37 %, and 68.99 %, respectively. The cancer-specific survival was 98.73 % (12 months), 87.81 % (36 months), and 80.17 % (60 months). Laparoscopy-assisted right hemicolectomy with D3 lymphadenectomy can be successfully performed for right colon cancer with the advantages of minimally invasive surgery. Moreover, the results implied appropriate short- and long-term outcomes.
Advanced 3D image processing techniques for liver and hepatic tumor location and volumetry
NASA Astrophysics Data System (ADS)
Chemouny, Stephane; Joyeux, Henri; Masson, Bruno; Borne, Frederic; Jaeger, Marc; Monga, Olivier
1999-05-01
To assist radiologists and physicians in diagnosing, and in treatment planning and evaluating in liver oncology, we have developed a fast and accurate segmentation of the liver and its lesions within CT-scan exams. The first step of our method is to reduce spatial resolution of CT images. This will have two effects: obtain near isotropic 3D data space and drastically decrease computational time for further processing. On a second step a 3D non-linear `edge- preserving' smoothing filtering is performed throughout the entire exam. On a third step the 3D regions coming out from the second step are homogeneous enough to allow a quite simple segmentation process, based on morphological operations, under supervisor control, ending up with accurate 3D regions of interest (ROI) of the liver and all the hepatic tumors. On a fourth step the ROIs are eventually set back into the original images, features like volume and location are immediately computed and displayed. The segmentation we get is as precise as a manual one but is much faster.
3D-CAD Effects on Creative Design Performance of Different Spatial Abilities Students
ERIC Educational Resources Information Center
Chang, Y.
2014-01-01
Students' creativity is an important focus globally and is interrelated with students' spatial abilities. Additionally, three-dimensional computer-assisted drawing (3D-CAD) overcomes barriers to spatial expression during the creative design process. Does 3D-CAD affect students' creative abilities? The purpose of this study was to explore the…
Ha, Kyungyeon; Choi, Hoseop; Jung, Kinam; Han, Kyuhee; Lee, Jong-Kwon; Ahn, KwangJun; Choi, Mansoo
2014-06-06
We present an approach utilizing ion assisted aerosol lithography (IAAL) with a newly designed multi-pin spark discharge generator (SDG) for fabricating large-area three-dimensional (3D) nanoparticle-structure (NPS) arrays. The design of the multi-pin SDG allows us to uniformly construct 3D NPSs on a large area of 50 mm × 50 mm in a parallel fashion at atmospheric pressure. The ion-induced focusing capability of IAAL significantly reduces the feature size of 3D NPSs compared to that of the original pre-patterns formed on a substrate. The spatial uniformity of 3D NPSs is above 95% using the present multi-pin SDG, which is far superior to that of the previous single-pin SDG with less than 32% uniformity. The effect of size distributions of nanoparticles generated via the multi-pin SDG on the 3D NPSs also has been studied. In addition, we measured spectral reflectance for the present 3D NPSs coated with Ag, demonstrating enhanced diffuse reflectance.
NASA Astrophysics Data System (ADS)
Ha, Kyungyeon; Choi, Hoseop; Jung, Kinam; Han, Kyuhee; Lee, Jong-Kwon; Ahn, KwangJun; Choi, Mansoo
2014-06-01
We present an approach utilizing ion assisted aerosol lithography (IAAL) with a newly designed multi-pin spark discharge generator (SDG) for fabricating large-area three-dimensional (3D) nanoparticle-structure (NPS) arrays. The design of the multi-pin SDG allows us to uniformly construct 3D NPSs on a large area of 50 mm × 50 mm in a parallel fashion at atmospheric pressure. The ion-induced focusing capability of IAAL significantly reduces the feature size of 3D NPSs compared to that of the original pre-patterns formed on a substrate. The spatial uniformity of 3D NPSs is above 95% using the present multi-pin SDG, which is far superior to that of the previous single-pin SDG with less than 32% uniformity. The effect of size distributions of nanoparticles generated via the multi-pin SDG on the 3D NPSs also has been studied. In addition, we measured spectral reflectance for the present 3D NPSs coated with Ag, demonstrating enhanced diffuse reflectance.
Integrated Cancer Research in Five Thematic Areas in Interest
2005-07-01
Professor of Urology (on-going RSU), Howard Crawford, PhD, Assistant Professor of Pharmacological Sciences (on-going RSU), Marjana Maletic- Savatic ...young scientists. Drs. Adler, Crawford, Maletic- Savatic received base support from this mechanism as they further develop their research programs...Mirjana Maletic- Savatic , MD-PhD, Assistant Professor Neurology: Human Neural Stem Cells - In Vivo Models for Cerebral Carcinoma The study of human
Neochoritis, Constantinos G; Zarganes-Tzitzikas, Tryfon; Tsoleridis, Constantinos A; Stephanidou-Stephanatou, Julia; Kontogiorgis, Christos A; Hadjipavlou-Litina, Dimitra J; Choli-Papadopoulou, Theodora
2011-01-01
The synthesis of a number of benzimidazole Schiff bases 3 and 3-oxo-pyrimido[1,2-a]benzimidazoles 4 in excellent yields by a one-step sequence from the reaction of 2-aminobenzimidazole under green chemistry conditions is described. Structural assignments of the new compounds as well as complete assignment of (1)H and (13)C NMR signals have been unambiguously achieved based on the analysis of their (1)H and (13)C NMR (1D and 2D), IR, MS and elemental analysis data. To the synthesized Schiff bases the E-configuration was assigned on the basis of comparison of experimental and calculated (DFT) (13)C NMR chemical shifts. Compounds 3 and 4 were evaluated as inhibitors of lipoxygenase (LOX) and of lipid peroxidation (LPO). All the tested derivatives showed inhibition of lipid peroxidation, whereas most of them were found to have higher activation than the reference compound trolox; The Schiff bases 3e, 3h, and 3i, and the pyrimidobenzimidazoles 4a, 4e and 4f were found to be the most potent. The most potent LOX inhibitor within the subset of Schiff bases was found compound 3i, followed by 3f, whereas compounds 4a and 4g were found the most potent of the 3-oxo-pyrimido[1,2-a]benzimidazole group. Moreover, some cytotoxicity assessments were undertaken, whereupon it was found that Schiff base 3i and pyrimidobenzimidazoles 4e and 4f did not exhibit cytotoxicity at similar concentrations resembling thus the inhibitory activity of lipid peroxidation. The most cytotoxic Schiff base and pyrimidobenzimidazole were found to be 3d and 4c, respectively. Copyright © 2010 Elsevier Masson SAS. All rights reserved.
Kim, Myungjoon; Lee, Chiwon; Park, Woo Jung; Suh, Yun Suhk; Yang, Han Kwang; Kim, H Jin; Kim, Sungwan
2016-05-20
Robot-assisted laparoscopic surgery offers several advantages compared with open surgery and conventional minimally invasive surgery. However, one issue that needs to be resolved is a collision between the robot arm and the assistant instrument. This is mostly caused by miscommunication between the surgeon and the assistant. To resolve this limitation, an assistant surgical robot system that can be simultaneously manipulated via a wireless controller is proposed to allow the surgeon to control the assistant instrument. The system comprises two novel master interfaces (NMIs), a surgical instrument with a gripper actuated by a micromotor, and 6-axis robot arm. Two NMIs are attached to master tool manipulators of da Vinci research kit (dVRK) to control the proposed system simultaneously with patient side manipulators of dVRK. The developments of the surgical instrument and NMI are based on surgical-operation-by-wire concept and hands-on-throttle-and-stick concept from the earlier research, respectively. Tests for checking the accuracy, latency, and power consumption of the NMI are performed. The gripping force, reaction time, and durability are assessed to validate the surgical instrument. The workspace is calculated for estimating the clinical applicability. A simple peg task using the fundamentals of laparoscopic surgery board and an in vitro test are executed with three novice volunteers. The NMI was operated for 185 min and reflected the surgeon's decision successfully with a mean latency of 132 ms. The gripping force of the surgical instrument was comparable to that of conventional systems and was consistent even after 1000 times of gripping motion. The reaction time was 0.4 s. The workspace was calculated to be 8397.4 cm(3). Recruited volunteers were able to execute the simple peg task within the cut-off time and successfully performed the in vitro test without any collision. Various experiments were conducted and it is verified that the proposed assistant surgical robot system enables collision-free and simultaneous operation of the dVRK's robot arm and the proposed assistant robot arm. The workspace is appropriate for the performance of various kinds of surgeries. Therefore, the proposed system is expected to provide higher safety and effectiveness for the current surgical robot system.
NASA Astrophysics Data System (ADS)
Hong, Wei; Wang, Jinqing; Gong, Peiwei; Sun, Jinfeng; Niu, Lengyuan; Yang, Zhigang; Wang, Zhaofeng; Yang, Shengrong
2014-12-01
Electrodes with rationally designed hybrid nanostructures can offer many opportunities for the enhanced performance in electrochemical energy storage. In this work, the uniform 2D Co3O4-based building blocks have been prepared through a facile chemical etching assistant approach and a following treatment of thermal annealing. The obtained nanosheets array has been directly employed as 2D backbone for the subsequent construction of hybrid nanostructure of Co3O4@NiMoO4 by a simple hydrothermal synthesis. As a binder-free electrode, the constructed 3D hybrid nanostructures exhibit a high specific capacitance of 1526 F g-1 at a current density of 3 mA cm-2 and a capacitance retention of 72% with the increase of current density from 3 mA cm-2 to 30 mA cm-2. Moreover, an asymmetric supercapacitor based on this hybrid Co3O4@NiMoO4 and activated carbon can deliver a maximum energy density of 37.8 Wh kg-1 at a power density of 482 W kg-1. The outstanding electrochemical behaviors presented here suggest that this hybrid nanostructured material has potential applications in energy storage.
Chen, Yuan-Chang; Sun, Zhen-Kui; Li, Ming-Hua; Li, Yong-Dong; Wang, Wu; Tan, Hua-Qiao; Gu, Bin-Xian; Chen, Shi-Wen
2012-07-01
To evaluate the clinical value of unenhanced magnetic resonance angiography (MRA) at 3.0 T for the diagnosis and therapeutic planning of patients with subarachnoid haemorrhage (SAH). A total of 165 patients with SAH were referred for three-dimensional time-of-flight MRA (3D-TOF-MRA) before digital subtraction angiography (DSA). For each aneurysm, 3D-TOF-MRA was used to determine whether the aneurysm was suitable for coil placement with or without balloon/stent-assisted coiling, surgical clipping or conservative treatment. Treatment planning with 3D-TOF-MRA was compared with actual treatment decisions or treatment that had been carried out in each aneurysm decided using DSA. The aneurysm-based evaluation yielded accuracy of 96.9%, sensitivity of 97.6%, specificity of 93.1%, positive predictive value (PPV) of 98.8% and negative predictive value (NPV) of 87.1%, in the detection of intracranial aneurysms. Treatment planning could be correctly made on the basis of aneurysm anatomy and working view by volume rendering (VR) 3D-TOF-MRA with accuracy, sensitivity, specificity, PPV and NPV of 94.9%, 94.0%, 100%, 100% and 74.4%, respectively, on a per aneurysm-based evaluation. VR 3D-TOF-MRA offers high diagnostic accuracy in the detection of ruptured intracranial aneurysms, and appears to be an effective treatment planning tool for most patients with SAH. VR 3D-TOF-MRA offers high diagnostic accuracy for detecting ruptured intracranial aneurysms. • VR 3D-TOF-MRA helps treatment planning for patients with subarachnoid haemorrhage. • 3D-TOF-MRA is non-invasive and avoids using ionising radiation or contrast agents.
Using x-ray mammograms to assist in microwave breast image interpretation.
Curtis, Charlotte; Frayne, Richard; Fear, Elise
2012-01-01
Current clinical breast imaging modalities include ultrasound, magnetic resonance (MR) imaging, and the ubiquitous X-ray mammography. Microwave imaging, which takes advantage of differing electromagnetic properties to obtain image contrast, shows potential as a complementary imaging technique. As an emerging modality, interpretation of 3D microwave images poses a significant challenge. MR images are often used to assist in this task, and X-ray mammograms are readily available. However, X-ray mammograms provide 2D images of a breast under compression, resulting in significant geometric distortion. This paper presents a method to estimate the 3D shape of the breast and locations of regions of interest from standard clinical mammograms. The technique was developed using MR images as the reference 3D shape with the future intention of using microwave images. Twelve breast shapes were estimated and compared to ground truth MR images, resulting in a skin surface estimation accurate to within an average Euclidean distance of 10 mm. The 3D locations of regions of interest were estimated to be within the same clinical area of the breast as corresponding regions seen on MR imaging. These results encourage investigation into the use of mammography as a source of information to assist with microwave image interpretation as well as validation of microwave imaging techniques.
Stereoselective virtual screening of the ZINC database using atom pair 3D-fingerprints.
Awale, Mahendra; Jin, Xian; Reymond, Jean-Louis
2015-01-01
Tools to explore large compound databases in search for analogs of query molecules provide a strategically important support in drug discovery to help identify available analogs of any given reference or hit compound by ligand based virtual screening (LBVS). We recently showed that large databases can be formatted for very fast searching with various 2D-fingerprints using the city-block distance as similarity measure, in particular a 2D-atom pair fingerprint (APfp) and the related category extended atom pair fingerprint (Xfp) which efficiently encode molecular shape and pharmacophores, but do not perceive stereochemistry. Here we investigated related 3D-atom pair fingerprints to enable rapid stereoselective searches in the ZINC database (23.2 million 3D structures). Molecular fingerprints counting atom pairs at increasing through-space distance intervals were designed using either all atoms (16-bit 3DAPfp) or different atom categories (80-bit 3DXfp). These 3D-fingerprints retrieved molecular shape and pharmacophore analogs (defined by OpenEye ROCS scoring functions) of 110,000 compounds from the Cambridge Structural Database with equal or better accuracy than the 2D-fingerprints APfp and Xfp, and showed comparable performance in recovering actives from decoys in the DUD database. LBVS by 3DXfp or 3DAPfp similarity was stereoselective and gave very different analogs when starting from different diastereomers of the same chiral drug. Results were also different from LBVS with the parent 2D-fingerprints Xfp or APfp. 3D- and 2D-fingerprints also gave very different results in LBVS of folded molecules where through-space distances between atom pairs are much shorter than topological distances. 3DAPfp and 3DXfp are suitable for stereoselective searches for shape and pharmacophore analogs of query molecules in large databases. Web-browsers for searching ZINC by 3DAPfp and 3DXfp similarity are accessible at www.gdb.unibe.ch and should provide useful assistance to drug discovery projects. Graphical abstractAtom pair fingerprints based on through-space distances (3DAPfp) provide better shape encoding than atom pair fingerprints based on topological distances (APfp) as measured by the recovery of ROCS shape analogs by fp similarity.
NASA Astrophysics Data System (ADS)
Li, Zhenwei; Sun, Jianyong; Zhang, Jianguo
2012-02-01
As more and more CT/MR studies are scanning with larger volume of data sets, more and more radiologists and clinician would like using PACS WS to display and manipulate these larger data sets of images with 3D rendering features. In this paper, we proposed a design method and implantation strategy to develop 3D image display component not only with normal 3D display functions but also with multi-modal medical image fusion as well as compute-assisted diagnosis of coronary heart diseases. The 3D component has been integrated into the PACS display workstation of Shanghai Huadong Hospital, and the clinical practice showed that it is easy for radiologists and physicians to use these 3D functions such as multi-modalities' (e.g. CT, MRI, PET, SPECT) visualization, registration and fusion, and the lesion quantitative measurements. The users were satisfying with the rendering speeds and quality of 3D reconstruction. The advantages of the component include low requirements for computer hardware, easy integration, reliable performance and comfortable application experience. With this system, the radiologists and the clinicians can manipulate with 3D images easily, and use the advanced visualization tools to facilitate their work with a PACS display workstation at any time.
A Program of Ground-Based Astronomy to Complement Einstein Observations.
1982-11-30
Astronomy D T I C i CO-,,, Uv I,. WA TOPE: -. Gary A. Cbanan Assistant Professor of Phy.3[cs i t0V.l.., 1982 %30 0 ii CONTENTS Page A. REPORT DOCUMENTATION...block number) A total of eight ground-based astronomical observing programs were carried out in pursuit of a multiwavelength approach to a number of...astro- physical problems. Synthesis of these results with existing X-ray data led to considerable progress on problems of the emission mechanisms and
Li, Yao; Qian, Dan; Xue, Jiawei; ...
2015-11-02
Synchrotron X-ray microdiffraction was employed to investigate the inhomogeneous distribution of defect and residual strain in the transitional region between the dendritic and stray grains in a laser-assisted 3D printed Ni-based superalloy. The dendritic region was found to be under tensile strain transversely to the primary dendrite arm directions. The dendrite edges, where high level of strains and geometrically necessary dislocations were detected, were discerned as low angle grain boundaries. Lastly, high angle grain boundaries were observed in the stray grain region, and the orientation of the strain tensor in this region varied dramatically at the micron scale, in contrastmore » with the more or less homogeneous distribution in the dendritic region.« less
Raman Spectroscopy of 3-D Printed Polymers
NASA Astrophysics Data System (ADS)
Espinoza, Vanessa; Wood, Erin; Hight Walker, Angela; Seppala, Jonathan; Kotula, Anthony
Additive manufacturing (AM) techniques, such as 3-D printing are becoming an innovative and efficient way to produce highly customized parts for applications ranging from automotive to biomedical. Polymer-based AM parts can be produced from a myriad of materials and processing conditions to enable application-specific products. However, bringing 3-D printing from prototype to production relies on understanding the effect of processing conditions on the final product. Raman spectroscopy is a powerful and non-destructive characterization technique that can assist in determining the chemical homogeneity and physical alignment of polymer chains in 3-D printed materials. Two polymers commonly used in 3-D printing, acrylonitrile butadiene styrene (ABS) and polycarbonate (PC), were investigated using 1- and 2-D hyperspectral Raman imaging. In the case of ABS, a complex thermoplastic, the homogeneity of the material through the weld zone was investigated by comparing Raman peaks from each of the three components. In order to investigate the effect of processing conditions on polymer chain alignment, polarized Raman spectroscopy was used. In particular, the print speed or shear rate and effect of strain on PC filaments was investigated with perpendicular and parallel polarizations. National Institute of Standards and Technology Gaithersburg, MD ; Society of Physics Students.
Making the Best of It? Exploring the Realities of 3D Printing in School
ERIC Educational Resources Information Center
Nemorin, Selena; Selwyn, Neil
2017-01-01
Digital fabrication and "3D Making" are prominent recent additions to school curricula, hastened by the increased affordability of Computer Assisted Design software and devices such as 3D printers. It is increasingly argued that classroom use of these technologies can re-orientate schools towards forms of skills and knowledge appropriate…
Multimaterial magnetically assisted 3D printing of composite materials.
Kokkinis, Dimitri; Schaffner, Manuel; Studart, André R
2015-10-23
3D printing has become commonplace for the manufacturing of objects with unusual geometries. Recent developments that enabled printing of multiple materials indicate that the technology can potentially offer a much wider design space beyond unusual shaping. Here we show that a new dimension in this design space can be exploited through the control of the orientation of anisotropic particles used as building blocks during a direct ink-writing process. Particle orientation control is demonstrated by applying low magnetic fields on deposited inks pre-loaded with magnetized stiff platelets. Multimaterial dispensers and a two-component mixing unit provide additional control over the local composition of the printed material. The five-dimensional design space covered by the proposed multimaterial magnetically assisted 3D printing platform (MM-3D printing) opens the way towards the manufacturing of functional heterogeneous materials with exquisite microstructural features thus far only accessible by biological materials grown in nature.
Akiba, Tadashi; Marushima, Hideki; Harada, Junta; Kobayashi, Susumu; Morikawa, Toshiaki
2009-01-01
Video-assisted thoracic surgery (VATS) has recently been adopted for complicated anatomical lung resections. During these thoracoscopic procedures, surgeons view the operative field on a two-dimensional (2-D) video monitor and cannot palpate the organ directly, thus frequently encountering anatomical difficulties. This study aimed to estimate the usefulness of preoperative three-dimensional (3-D) imaging of thoracic organs. We compared the preoperative 64-row three-dimensional multidetector computed tomography (3DMDCT) findings of lung cancer-affected thoracic organs to the operative findings. In comparison to the operative findings, the branches of pulmonary arteries, veins, and bronchi were well defined in the 3D-MDCT images of 27 patients. 3D-MDCT imaging is useful for preoperatively understanding the individual thoracic anatomy in lung cancer surgery. This modality can therefore contribute to safer anatomical pulmonary operations, especially in VATS.
Multimaterial magnetically assisted 3D printing of composite materials
NASA Astrophysics Data System (ADS)
Kokkinis, Dimitri; Schaffner, Manuel; Studart, André R.
2015-10-01
3D printing has become commonplace for the manufacturing of objects with unusual geometries. Recent developments that enabled printing of multiple materials indicate that the technology can potentially offer a much wider design space beyond unusual shaping. Here we show that a new dimension in this design space can be exploited through the control of the orientation of anisotropic particles used as building blocks during a direct ink-writing process. Particle orientation control is demonstrated by applying low magnetic fields on deposited inks pre-loaded with magnetized stiff platelets. Multimaterial dispensers and a two-component mixing unit provide additional control over the local composition of the printed material. The five-dimensional design space covered by the proposed multimaterial magnetically assisted 3D printing platform (MM-3D printing) opens the way towards the manufacturing of functional heterogeneous materials with exquisite microstructural features thus far only accessible by biological materials grown in nature.
DOE Office of Scientific and Technical Information (OSTI.GOV)
De Silva, T; Ketcha, M; Siewerdsen, J H
Purpose: In image-guided spine surgery, mapping 3D preoperative images to 2D intraoperative images via 3D-2D registration can provide valuable assistance in target localization. However, the presence of surgical instrumentation, hardware implants, and soft-tissue resection/displacement causes mismatches in image content, confounding existing registration methods. Manual/semi-automatic methods to mask such extraneous content is time consuming, user-dependent, error prone, and disruptive to clinical workflow. We developed and evaluated 2 novel similarity metrics within a robust registration framework to overcome such challenges in target localization. Methods: An IRB-approved retrospective study in 19 spine surgery patients included 19 preoperative 3D CT images and 50 intraoperativemore » mobile radiographs in cervical, thoracic, and lumbar spine regions. A neuroradiologist provided truth definition of vertebral positions in CT and radiography. 3D-2D registration was performed using the CMA-ES optimizer with 4 gradient-based image similarity metrics: (1) gradient information (GI); (2) gradient correlation (GC); (3) a novel variant referred to as gradient orientation (GO); and (4) a second variant referred to as truncated gradient correlation (TGC). Registration accuracy was evaluated in terms of the projection distance error (PDE) of the vertebral levels. Results: Conventional similarity metrics were susceptible to gross registration error and failure modes associated with the presence of surgical instrumentation: for GI, the median PDE and interquartile range was 33.0±43.6 mm; similarly for GC, PDE = 23.0±92.6 mm respectively. The robust metrics GO and TGC, on the other hand, demonstrated major improvement in PDE (7.6 ±9.4 mm and 8.1± 18.1 mm, respectively) and elimination of gross failure modes. Conclusion: The proposed GO and TGC similarity measures improve registration accuracy and robustness to gross failure in the presence of strong image content mismatch. Such registration capability could offer valuable assistance in target localization without disruption of clinical workflow. G. Kleinszig and S. Vogt are employees of Siemens Healthcare.« less
Using a wireless motion controller for 3D medical image catheter interactions
NASA Astrophysics Data System (ADS)
Vitanovski, Dime; Hahn, Dieter; Daum, Volker; Hornegger, Joachim
2009-02-01
State-of-the-art morphological imaging techniques usually provide high resolution 3D images with a huge number of slices. In clinical practice, however, 2D slice-based examinations are still the method of choice even for these large amounts of data. Providing intuitive interaction methods for specific 3D medical visualization applications is therefore a critical feature for clinical imaging applications. For the domain of catheter navigation and surgery planning, it is crucial to assist the physician with appropriate visualization techniques, such as 3D segmentation maps, fly-through cameras or virtual interaction approaches. There has been an ongoing development and improvement for controllers that help to interact with 3D environments in the domain of computer games. These controllers are based on both motion and infrared sensors and are typically used to detect 3D position and orientation. We have investigated how a state-of-the-art wireless motion sensor controller (Wiimote), developed by Nintendo, can be used for catheter navigation and planning purposes. By default the Wiimote controller only measure rough acceleration over a range of +/- 3g with 10% sensitivity and orientation. Therefore, a pose estimation algorithm was developed for computing accurate position and orientation in 3D space regarding 4 Infrared LEDs. Current results show that for the translation it is possible to obtain a mean error of (0.38cm, 0.41cm, 4.94cm) and for the rotation (0.16, 0.28) respectively. Within this paper we introduce a clinical prototype that allows steering of a virtual fly-through camera attached to the catheter tip by the Wii controller on basis of a segmented vessel tree.
Automatic 3D liver segmentation based on deep learning and globally optimized surface evolution
NASA Astrophysics Data System (ADS)
Hu, Peijun; Wu, Fa; Peng, Jialin; Liang, Ping; Kong, Dexing
2016-12-01
The detection and delineation of the liver from abdominal 3D computed tomography (CT) images are fundamental tasks in computer-assisted liver surgery planning. However, automatic and accurate segmentation, especially liver detection, remains challenging due to complex backgrounds, ambiguous boundaries, heterogeneous appearances and highly varied shapes of the liver. To address these difficulties, we propose an automatic segmentation framework based on 3D convolutional neural network (CNN) and globally optimized surface evolution. First, a deep 3D CNN is trained to learn a subject-specific probability map of the liver, which gives the initial surface and acts as a shape prior in the following segmentation step. Then, both global and local appearance information from the prior segmentation are adaptively incorporated into a segmentation model, which is globally optimized in a surface evolution way. The proposed method has been validated on 42 CT images from the public Sliver07 database and local hospitals. On the Sliver07 online testing set, the proposed method can achieve an overall score of 80.3+/- 4.5 , yielding a mean Dice similarity coefficient of 97.25+/- 0.65 % , and an average symmetric surface distance of 0.84+/- 0.25 mm. The quantitative validations and comparisons show that the proposed method is accurate and effective for clinical application.
Real-time 3D image reconstruction guidance in liver resection surgery
Nicolau, Stephane; Pessaux, Patrick; Mutter, Didier; Marescaux, Jacques
2014-01-01
Background Minimally invasive surgery represents one of the main evolutions of surgical techniques. However, minimally invasive surgery adds difficulty that can be reduced through computer technology. Methods From a patient’s medical image [US, computed tomography (CT) or MRI], we have developed an Augmented Reality (AR) system that increases the surgeon’s intraoperative vision by providing a virtual transparency of the patient. AR is based on two major processes: 3D modeling and visualization of anatomical or pathological structures appearing in the medical image, and the registration of this visualization onto the real patient. We have thus developed a new online service, named Visible Patient, providing efficient 3D modeling of patients. We have then developed several 3D visualization and surgical planning software tools to combine direct volume rendering and surface rendering. Finally, we have developed two registration techniques, one interactive and one automatic providing intraoperative augmented reality view. Results From January 2009 to June 2013, 769 clinical cases have been modeled by the Visible Patient service. Moreover, three clinical validations have been realized demonstrating the accuracy of 3D models and their great benefit, potentially increasing surgical eligibility in liver surgery (20% of cases). From these 3D models, more than 50 interactive AR-assisted surgical procedures have been realized illustrating the potential clinical benefit of such assistance to gain safety, but also current limits that automatic augmented reality will overcome. Conclusions Virtual patient modeling should be mandatory for certain interventions that have now to be defined, such as liver surgery. Augmented reality is clearly the next step of the new surgical instrumentation but remains currently limited due to the complexity of organ deformations during surgery. Intraoperative medical imaging used in new generation of automated augmented reality should solve this issue thanks to the development of Hybrid OR. PMID:24812598
NASA Astrophysics Data System (ADS)
Gwamuri, J.; Pearce, Joshua M.
2017-08-01
The recent introduction of RepRap (self-replicating rapid prototyper) 3-D printers and the resultant open source technological improvements have resulted in affordable 3-D printing, enabling low-cost distributed manufacturing for individuals. This development and others such as the rise of open source-appropriate technology (OSAT) and solar powered 3-D printing are moving 3-D printing from an industry based technology to one that could be used in the developing world for sustainable development. In this paper, we explore some specific technological improvements and how distributed manufacturing with open-source 3-D printing can be used to provide open-source 3-D printable optics components for developing world communities through the ability to print less expensive and customized products. This paper presents an open-source low cost optical equipment library which enables relatively easily adapted customizable designs with the potential of changing the way optics is taught in resource constraint communities. The study shows that this method of scientific hardware development has a potential to enables a much broader audience to participate in optical experimentation both as research and teaching platforms. Conclusions on the technical viability of 3-D printing to assist in development and recommendations on how developing communities can fully exploit this technology to improve the learning of optics through hands-on methods have been outlined.
Gao, Peng; Liu, Peng; Su, Hongsen; Qiao, Liang
2015-04-01
Integrating visualization toolkit and the capability of interaction, bidirectional communication and graphics rendering which provided by HTML5, we explored and experimented on the feasibility of remote medical image reconstruction and interaction in pure Web. We prompted server-centric method which did not need to download the big medical data to local connections and avoided considering network transmission pressure and the three-dimensional (3D) rendering capability of client hardware. The method integrated remote medical image reconstruction and interaction into Web seamlessly, which was applicable to lower-end computers and mobile devices. Finally, we tested this method in the Internet and achieved real-time effects. This Web-based 3D reconstruction and interaction method, which crosses over internet terminals and performance limited devices, may be useful for remote medical assistant.
Yang, Chengliang; Mo, Lili; Ma, Yegang; Peng, Guilin; Ren, Yi; Wang, Wei; Liu, Yongyu
2015-01-01
Background Three-dimensional (3D) vision systems are now available for thoracic surgery. It is unclear whether 3D video-assisted thoracic surgery (VATS) is superior to 2D VATS systems. This study aimed to compare the operative and perioperative data between 2D and 3D VATS lobectomy (VTL) and to identify the actual role of 3D VTL in thoracic surgery. Methods A two-institutional comparative study was conducted from November 2013 to November 2014 at Liaoning Cancer Hospital & Institute and the First Affiliated Hospital of Guangzhou Medical University, China, of 300 patients with resectable non-small cell lung cancer (NSCLC). Patients were assigned to receive either the 3D VATS (n=150) or 2D VATS (n=150) lobectomy. The operative and perioperative data between 2D VATS and 3D VATS were compared. Results Although there was no significant difference between the two groups regarding the incidence of each single complication, a significantly less operative time was found in the 3D VATS group (145 min) than in the 2D VATS group (176 min) (P=0.006). Postoperative mortality rates in 3D VATS and 2D VATS groups were both 0%.No significant difference was found between groups for estimated blood loss (P=0.893), chest drainage tube placement time (P=0.397), length of hospital stay (P=0.199), number of lymph nodes resected (P=0.397), postoperative complications (P=0.882) and cost of care (P=0.913). Conclusions Early results of this study demonstrate that the 3D VATS lobectomy procedure can be performed with less operative time. 3D VATS and 2D VATS lobectomy are both safe procedures in first-line surgical treatment of NSCLC. PMID:26623103
Three-dimensional choroidal segmentation in spectral OCT volumes using optic disc prior information
NASA Astrophysics Data System (ADS)
Hu, Zhihong; Girkin, Christopher A.; Hariri, Amirhossein; Sadda, SriniVas R.
2016-03-01
Recently, much attention has been focused on determining the role of the peripapillary choroid - the layer between the outer retinal pigment epithelium (RPE)/Bruchs membrane (BM) and choroid-sclera (C-S) junction, whether primary or secondary in the pathogenesis of glaucoma. However, the automated choroidal segmentation in spectral-domain optical coherence tomography (SD-OCT) images of optic nerve head (ONH) has not been reported probably due to the fact that the presence of the BM opening (BMO, corresponding to the optic disc) can deflect the choroidal segmentation from its correct position. The purpose of this study is to develop a 3D graph-based approach to identify the 3D choroidal layer in ONH-centered SD-OCT images using the BMO prior information. More specifically, an initial 3D choroidal segmentation was first performed using the 3D graph search algorithm. Note that varying surface interaction constraints based on the choroidal morphological model were applied. To assist the choroidal segmentation, two other surfaces of internal limiting membrane and innerouter segment junction were also segmented. Based on the segmented layer between the RPE/BM and C-S junction, a 2D projection map was created. The BMO in the projection map was detected by a 2D graph search. The pre-defined BMO information was then incorporated into the surface interaction constraints of the 3D graph search to obtain more accurate choroidal segmentation. Twenty SD-OCT images from 20 healthy subjects were used. The mean differences of the choroidal borders between the algorithm and manual segmentation were at a sub-voxel level, indicating a high level segmentation accuracy.
RNA2D3D: a program for generating, viewing, and comparing 3-dimensional models of RNA.
Martinez, Hugo M; Maizel, Jacob V; Shapiro, Bruce A
2008-06-01
Using primary and secondary structure information of an RNA molecule, the program RNA2D3D automatically and rapidly produces a first-order approximation of a 3-dimensional conformation consistent with this information. Applicable to structures of arbitrary branching complexity and pseudoknot content, it features efficient interactive graphical editing for the removal of any overlaps introduced by the initial generating procedure and for making conformational changes favorable to targeted features and subsequent refinement. With emphasis on fast exploration of alternative 3D conformations, one may interactively add or delete base-pairs, adjacent stems can be coaxially stacked or unstacked, single strands can be shaped to accommodate special constraints, and arbitrary subsets can be defined and manipulated as rigid bodies. Compaction, whereby base stacking within stems is optimally extended into connecting single strands, is also available as a means of strategically making the structures more compact and revealing folding motifs. Subsequent refinement of the first-order approximation, of modifications, and for the imposing of tertiary constraints is assisted with standard energy refinement techniques. Previously determined coordinates for any part of the molecule are readily incorporated, and any part of the modeled structure can be output as a PDB or XYZ file. Illustrative applications in the areas of ribozymes, viral kissing loops, viral internal ribosome entry sites, and nanobiology are presented.
Generic Dynamic Environment Perception Using Smart Mobile Devices
Danescu, Radu; Itu, Razvan; Petrovai, Andra
2016-01-01
The driving environment is complex and dynamic, and the attention of the driver is continuously challenged, therefore computer based assistance achieved by processing image and sensor data may increase traffic safety. While active sensors and stereovision have the advantage of obtaining 3D data directly, monocular vision is easy to set up, and can benefit from the increasing computational power of smart mobile devices, and from the fact that almost all of them come with an embedded camera. Several driving assistance application are available for mobile devices, but they are mostly targeted for simple scenarios and a limited range of obstacle shapes and poses. This paper presents a technique for generic, shape independent real-time obstacle detection for mobile devices, based on a dynamic, free form 3D representation of the environment: the particle based occupancy grid. Images acquired in real time from the smart mobile device’s camera are processed by removing the perspective effect and segmenting the resulted bird-eye view image to identify candidate obstacle areas, which are then used to update the occupancy grid. The occupancy grid tracked cells are grouped into obstacles depicted as cuboids having position, size, orientation and speed. The easy to set up system is able to reliably detect most obstacles in urban traffic, and its measurement accuracy is comparable to a stereovision system. PMID:27763501
Study on Gap Flow Field Simulation in Small Hole Machining of Ultrasonic Assisted EDM
NASA Astrophysics Data System (ADS)
Liu, Yu; Chang, Hao; Zhang, Wenchao; Ma, Fujian; Sha, Zhihua; Zhang, Shengfang
2017-12-01
When machining a small hole with high aspect ratio in EDM, it is hard for the flushing liquid entering the bottom gap and the debris could hardly be removed, which results in the accumulation of debris and affects the machining efficiency and machining accuracy. The assisted ultrasonic vibration can improve the removal of debris in the gap. Based on dynamics simulation software Fluent, a 3D model of debris movement in the gap flow field of EDM small hole machining assisted with side flushing and ultrasonic vibration is established in this paper. When depth to ratio is 3, the laws of different amplitudes and frequencies on debris distribution and removal are quantitatively analysed. The research results show that periodic ultrasonic vibration can promote the movement of debris, which is beneficial to the removal of debris in the machining gap. Compared to traditional small hole machining in EDM, the debris in the machining gap is greatly reduced, which ensures the stability of machining process and improves the machining efficiency.
Diamond knife-assisted deep anterior lamellar keratoplasty to manage keratoconus.
Vajpayee, Rasik B; Maharana, Prafulla K; Sharma, Namrata; Agarwal, Tushar; Jhanji, Vishal
2014-02-01
To evaluate the outcomes of a new surgical technique, diamond knife-assisted deep anterior lamellar keratoplasty (DALK), and compare its visual and refractive results with big-bubble DALK in cases of keratoconus. Tertiary eyecare hospital. Comparative case series. The visual and surgical outcomes of diamond knife-assisted DALK were compared with those of successful big-bubble DALK. Diamond knife-assisted DALK was performed in 19 eyes and big-bubble DALK, in 11 eyes. All surgeries were completed successfully. No intraoperative or postoperative complications occurred with diamond knife-assisted DALK. Six months after diamond knife-assisted DALK, the mean corrected distance visual acuity (CDVA) improved significantly from 1.87 logMAR ± 0.22 (SD) to 0.23 ± 0.06 logMAR, the mean keratometry improved from 65.99 ± 8.86 diopters (D) to 45.13 ± 1.16 D, and the mean keratometric cylinder improved from 7.99 ± 3.81 D to 2.87 ± 0.59 D (all P=.005). Postoperatively, the mean refractive astigmatism was 2.55 ± 0.49 D and the mean spherical equivalent was -1.97 ± 0.56 D. The mean logMAR CDVA (P = .06), postoperative keratometry (P=.64), refractive cylinder (P=.63), and endothelial cell loss (P=.11) were comparable between diamond knife-assisted DALK and big-bubble DALK. Diamond knife-assisted DALK was effective and predictable as a surgical technique for management of keratoconus cases. This technique has the potential to offer visual and refractive outcomes comparable to those of big-bubble DALK. No author has a financial or proprietary interest in any material or method mentioned. Copyright © 2013 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.
Ripley, Beth; Kelil, Tatiana; Cheezum, Michael K; Goncalves, Alexandra; Di Carli, Marcelo F; Rybicki, Frank J; Steigner, Mike; Mitsouras, Dimitrios; Blankstein, Ron
2016-01-01
3D printing is a promising technique that may have applications in medicine, and there is expanding interest in the use of patient-specific 3D models to guide surgical interventions. To determine the feasibility of using cardiac CT to print individual models of the aortic root complex for transcatheter aortic valve replacement (TAVR) planning as well as to determine the ability to predict paravalvular aortic regurgitation (PAR). This retrospective study included 16 patients (9 with PAR identified on blinded interpretation of post-procedure trans-thoracic echocardiography and 7 age, sex, and valve size-matched controls with no PAR). 3D printed models of the aortic root were created from pre-TAVR cardiac computed tomography data. These models were fitted with printed valves and predictions regarding post-implant PAR were made using a light transmission test. Aortic root 3D models were highly accurate, with excellent agreement between annulus measurements made on 3D models and those made on corresponding 2D data (mean difference of -0.34 mm, 95% limits of agreement: ± 1.3 mm). The 3D printed valve models were within 0.1 mm of their designed dimensions. Examination of the fit of valves within patient-specific aortic root models correctly predicted PAR in 6 of 9 patients (6 true positive, 3 false negative) and absence of PAR in 5 of 7 patients (5 true negative, 2 false positive). Pre-TAVR 3D-printing based on cardiac CT provides a unique patient-specific method to assess the physical interplay of the aortic root and implanted valves. With additional optimization, 3D models may complement traditional techniques used for predicting which patients are more likely to develop PAR. Copyright © 2016 Society of Cardiovascular Computed Tomography. Published by Elsevier Inc. All rights reserved.
She, Xiao-Wei; Gu, Yun-Bin; Xu, Chun; Li, Chang; Ding, Cheng; Chen, Jun; Zhao, Jun
2018-02-01
Compared to the pulmonary lobe, the anatomical structure of the pulmonary segment is relatively complex and prone to variation, thus the risk and difficulty of segmentectomy is increased. We compared three-dimensional computed tomography bronchography and angiography (3D-CTBA) combined with 3D video-assisted thoracic surgery (3D-VATS) to perform segmentectomy to conventional two-dimensional (2D)-VATS for the treatment of non-small cell lung cancer (NSCLC). We retrospectively reviewed the data of randomly selected patients who underwent 3D-CTBA combined with 3D-VATS (3D-CTBA-VATS) or 2D-VATS at the Department of Thoracic Surgery, The First Affiliated Hospital of Soochow University Hospital, from January 2014 to May 2017. The operative duration of 3D group was significantly shorter than the 2D group (P < 0.05). There was no significant difference in the number of dissected lymph nodes between the two groups (P > 0.05). The extent of intraoperative bleeding and postoperative drainage in the 3D group was significantly lower than in the 2D group (P < 0.05). Chest tube duration in the 3D group was shorter than in the 2D group (P < 0.05). Incidences of pulmonary infection, atelectasis, and arrhythmia were not statistically different between the two groups (P > 0.05). However, hemoptysis and pulmonary air leakage (>3d) occurred significantly less frequently in the 3D than in the 2D group (P < 0.05). 3D-CTBA-VATS is a more accurate and smooth technique and leads to reduced intraoperative and postoperative complications. © 2018 The Authors. Thoracic Cancer published by China Lung Oncology Group and John Wiley & Sons Australia, Ltd.
42 CFR 423.464 - Coordination of benefits with other providers of prescription drug coverage.
Code of Federal Regulations, 2010 CFR
2010-10-01
... per capita basis) for Part D eligible individuals enrolled in the Part D plan and the SPAP or entity... Part D eligible individuals; (ii) Provides assistance to Part D eligible individuals in all Part D plans without discriminating based upon the Part D plan in which an individual enrolls; (iii) Meets the...
Zeng, Canjun; Xiao, Jidong; Wu, Zhanglin; Huang, Wenhua
2015-01-01
The aim of this study is to evaluate the efficacy and feasibility of three-dimensional printing (3D printing) assisted internal fixation of unstable pelvic fracture from minimal invasive para-rectus abdominis approach. A total of 38 patients with unstable pelvic fractures were analyzed retrospectively from August 2012 to February 2014. All cases were treated operatively with internal fixation assisted by three-dimensional printing from minimal invasive para-rectus abdominis approach. Both preoperative CT and three-dimensional reconstruction were performed. Pelvic model was created by 3D printing. Data including the best entry points, plate position and direction and length of screw were obtained from simulated operation based on 3D printing pelvic model. The diaplasis and internal fixation were performed by minimal invasive para-rectus abdominis approach according to the optimized dada in real surgical procedure. Matta and Majeed score were used to evaluate currative effects after operation. According to the Matta standard, the outcome of the diaplasis achieved 97.37% with excellent and good. Majeed assessment showed 94.4% with excellent and good. The imageological examination showed consistency of internal fixation and simulated operation. The mean operation time was 110 minutes, mean intraoperative blood loss 320 ml, and mean incision length 6.5 cm. All patients have achieved clinical healing, with mean healing time of 8 weeks. Three-dimensional printing assisted internal fixation of unstable pelvic fracture from minimal invasive para-rectus abdominis approach is feasible and effective. This method has the advantages of trauma minimally, bleeding less, healing rapidly and satisfactory reduction, and worthwhile for spreading in clinical practice.
Ming, Xing; Li, Anan; Wu, Jingpeng; Yan, Cheng; Ding, Wenxiang; Gong, Hui; Zeng, Shaoqun; Liu, Qian
2013-01-01
Digital reconstruction of three-dimensional (3D) neuronal morphology from light microscopy images provides a powerful technique for analysis of neural circuits. It is time-consuming to manually perform this process. Thus, efficient computer-assisted approaches are preferable. In this paper, we present an innovative method for the tracing and reconstruction of 3D neuronal morphology from light microscopy images. The method uses a prediction and refinement strategy that is based on exploration of local neuron structural features. We extended the rayburst sampling algorithm to a marching fashion, which starts from a single or a few seed points and marches recursively forward along neurite branches to trace and reconstruct the whole tree-like structure. A local radius-related but size-independent hemispherical sampling was used to predict the neurite centerline and detect branches. Iterative rayburst sampling was performed in the orthogonal plane, to refine the centerline location and to estimate the local radius. We implemented the method in a cooperative 3D interactive visualization-assisted system named flNeuronTool. The source code in C++ and the binaries are freely available at http://sourceforge.net/projects/flneurontool/. We validated and evaluated the proposed method using synthetic data and real datasets from the Digital Reconstruction of Axonal and Dendritic Morphology (DIADEM) challenge. Then, flNeuronTool was applied to mouse brain images acquired with the Micro-Optical Sectioning Tomography (MOST) system, to reconstruct single neurons and local neural circuits. The results showed that the system achieves a reasonable balance between fast speed and acceptable accuracy, which is promising for interactive applications in neuronal image analysis.
Computer assisted optical biopsy for colorectal polyps
NASA Astrophysics Data System (ADS)
Navarro-Avila, Fernando J.; Saint-Hill-Febles, Yadira; Renner, Janis; Klare, Peter; von Delius, Stefan; Navab, Nassir; Mateus, Diana
2017-03-01
We propose a method for computer-assisted optical biopsy for colorectal polyps, with the final goal of assisting the medical expert during the colonoscopy. In particular, we target the problem of automatic classification of polyp images in two classes: adenomatous vs non-adenoma. Our approach is based on recent advancements in convolutional neural networks (CNN) for image representation. In the paper, we describe and compare four different methodologies to address the binary classification task: a baseline with classical features and a Random Forest classifier, two methods based on features obtained from a pre-trained network, and finally, the end-to-end training of a CNN. With the pre-trained network, we show the feasibility of transferring a feature extraction mechanism trained on millions of natural images, to the task of classifying adenomatous polyps. We then demonstrate further performance improvements when training the CNN for our specific classification task. In our study, 776 polyp images were acquired and histologically analyzed after polyp resection. We report a performance increase of the CNN-based approaches with respect to both, the conventional engineered features and to a state-of-the-art method based on videos and 3D shape features.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wang, Ruixue; Xu, Han; Yang, Bin
The crystalline phases and domain configuration in the morphotropic phase boundary composition Pb(Mg1/3Nb2/3)O3-0.34PbTiO3 (PMN-0.34PT) single crystal have been investigated by synchrotronbased X-ray 3D Reciprocal Space Mapping (3D-RSM) and Piezoresponse Force Microscopy. The coexistence of tetragonal (T) and monoclinic MC phases in this PMN-0.34PT single crystal is confirmed. The affiliation of each diffraction spot in the 3D-RSM was identified with the assistance of qualitative simulation. Most importantly, the twinning structure between different domains in such a mixed phase PMN-PT crystal is firmly clarified, and the spatial distribution of different twin domains is demonstrated. In addition, the lattice parameters of T andmore » MC phases in PMN-0.34PT single crystal as well as the tilting angles of crystal lattices caused by the interfacial lattice mismatch are determined.« less
ERIC Educational Resources Information Center
Kuo, Ming-Shiou; Chuang, Tsung-Yen
2013-01-01
The teaching of 3D digital game design requires the development of students' meta-skills, from story creativity to 3D model construction, and even the visualization process in design thinking. The characteristics a good game designer should possess have been identified as including redesign things, creativity thinking and the ability to…
Effects of Verbal Components in 3D Talking-Head on Pronunciation Learning among Non-Native Speakers
ERIC Educational Resources Information Center
Ali, Ahmad Zamzuri Mohamad; Segaran, Kogilathah; Hoe, Tan Wee
2015-01-01
This study was designed to investigate the benefit of inclusion of various verbal elements in 3D talking-head on pronunciation learning among non-native speakers. In particular, the study examines the effects of three different multimedia presentation strategies in 3D talking-head Mobile-Assisted-Language-Learning (MALL) on the learning…
Le Moal, Julien; Peillon, Christophe; Dacher, Jean-Nicolas
2018-01-01
Background The objective of our pilot study was to assess if three-dimensional (3D) reconstruction performed by Visible Patient™ could be helpful for the operative planning, efficiency and safety of robot-assisted segmentectomy. Methods Between 2014 and 2015, 3D reconstructions were provided by the Visible Patient™ online service and used for the operative planning of robotic segmentectomy. To obtain 3D reconstruction, the surgeon uploaded the anonymized computed tomography (CT) image of the patient to the secured Visible Patient™ server and then downloaded the model after completion. Results Nine segmentectomies were performed between 2014 and 2015 using a pre-operative 3D model. All 3D reconstructions met our expectations: anatomical accuracy (bronchi, arteries, veins, tumor, and the thoracic wall with intercostal spaces), accurate delimitation of each segment in the lobe of interest, margin resection, free space rotation, portability (smartphone, tablet) and time saving technique. Conclusions We have shown that operative planning by 3D CT using Visible Patient™ reconstruction is useful in our practice of robot-assisted segmentectomy. The main disadvantage is the high cost. Its impact on reducing complications and improving surgical efficiency is the object of an ongoing study. PMID:29600049
Le Moal, Julien; Peillon, Christophe; Dacher, Jean-Nicolas; Baste, Jean-Marc
2018-01-01
The objective of our pilot study was to assess if three-dimensional (3D) reconstruction performed by Visible Patient™ could be helpful for the operative planning, efficiency and safety of robot-assisted segmentectomy. Between 2014 and 2015, 3D reconstructions were provided by the Visible Patient™ online service and used for the operative planning of robotic segmentectomy. To obtain 3D reconstruction, the surgeon uploaded the anonymized computed tomography (CT) image of the patient to the secured Visible Patient™ server and then downloaded the model after completion. Nine segmentectomies were performed between 2014 and 2015 using a pre-operative 3D model. All 3D reconstructions met our expectations: anatomical accuracy (bronchi, arteries, veins, tumor, and the thoracic wall with intercostal spaces), accurate delimitation of each segment in the lobe of interest, margin resection, free space rotation, portability (smartphone, tablet) and time saving technique. We have shown that operative planning by 3D CT using Visible Patient™ reconstruction is useful in our practice of robot-assisted segmentectomy. The main disadvantage is the high cost. Its impact on reducing complications and improving surgical efficiency is the object of an ongoing study.
Bertholet, Nicolas; Cheng, Debbie M; Palfai, Tibor P; Lloyd-Travaglini, Christine; Samet, Jeffrey H; Saitz, Richard
This exploratory study aims to investigate whether anxiety, depression, and pain are associated with changes in marijuana use and drug use consequences among primary care patients. In all, 331 adult primary care patients with marijuana as the only drug used were followed prospectively to investigate associations between anxiety/depression symptoms (no/minimal symptoms; anxiety or depression symptoms; symptoms of both) and pain (1-10 scale: none [0]; low [1-3]; medium [4-6]; high [7-10]) (independent variables) and substance use outcomes in regression models. These outcomes were changes (over 6 months) in primary outcomes: marijuana use days (past 30); and drug use consequences (Short Inventory of Problems-Drugs [SIP-D]); secondary outcomes-drug use risk (Alcohol, Smoking, and Substance Involvement Screening Test [ASSIST] score for drugs). At baseline, 67% reported no/minimal anxiety/depression symptoms, 16% anxiety or depression symptoms, 17% both; 14% reported no pain, 16% low, 23% medium, 47% high pain level. Mean (SD) number of marijuana use days was 16.4 (11.6), mean SIP-D 5.9 (9.0), mean ASSIST 12.5 (7.8); no significant association was found between anxiety/depression and marijuana use changes. Given the same baseline status for SIP-D and ASSIST, respectively, those with anxiety or depression had greater increases in SIP-D (adjusted mean difference [95% confidence interval] +3.26 [1.20; 5.32], P = 0.004) and borderline significant increases in ASSIST (+3.27 [-0.12; 6.65], P = 0.06) compared with those without anxiety or depression; those with both anxiety and depression had greater increases in ASSIST (+5.42 [2.05; 8.79], P = 0.003), but not SIP-D (+1.80 [-0.46; 4.06], P = 0.12). There was no significant association between pain and marijuana use and SIP-D changes. Given the same baseline ASSIST level, those with high pain level had greater increases in ASSIST (+4.89 [1.05; 8.72], P = 0.04) compared with those with no pain. In these exploratory analyses, anxiety, depression, and high pain level appear to be associated with increases in drug-related harm among primary care patients using marijuana.
Three-dimensional printing of freeform helical microstructures: a review.
Farahani, R D; Chizari, K; Therriault, D
2014-09-21
Three-dimensional (3D) printing is a fabrication method that enables creation of structures from digital models. Among the different structures fabricated by 3D printing methods, helical microstructures attracted the attention of the researchers due to their potential in different fields such as MEMS, lab-on-a-chip systems, microelectronics and telecommunications. Here we review different types of 3D printing methods capable of fabricating 3D freeform helical microstructures. The techniques including two more common microfabrication methods (i.e., focused ion beam chemical vapour deposition and microstereolithography) and also five methods based on computer-controlled robotic direct deposition of ink filament (i.e., fused deposition modeling, meniscus-confined electrodeposition, conformal printing on a rotating mandrel, UV-assisted and solvent-cast 3D printings) and their advantages and disadvantages regarding their utilization for the fabrication of helical microstructures are discussed. Focused ion beam chemical vapour deposition and microstereolithography techniques enable the fabrication of very precise shapes with a resolution down to ∼100 nm. However, these techniques may have material constraints (e.g., low viscosity) and/or may need special process conditions (e.g., vacuum chamber) and expensive equipment. The five other techniques based on robotic extrusion of materials through a nozzle are relatively cost-effective, however show lower resolution and less precise features. The popular fused deposition modeling method offers a wide variety of printable materials but the helical microstructures manufactured featured a less precise geometry compared to the other printing methods discussed in this review. The UV-assisted and the solvent-cast 3D printing methods both demonstrated high performance for the printing of 3D freeform structures such as the helix shape. However, the compatible materials used in these methods were limited to UV-curable polymers and polylactic acid (PLA), respectively. Meniscus-confined electrodeposition is a flexible, low cost technique that is capable of fabricating 3D structures both in nano- and microscales including freeform helical microstructures (down to few microns) under room conditions using metals. However, the metals suitable for this technique are limited to those that can be electrochemically deposited with the use of an electrolyte solution. The highest precision on the helix geometry was achieved using the conformal printing on a rotating mandrel. This method offers the lowest shape deformation after printing but requires more tools (e.g., mandrel, motor) and the printed structure must be separated from the mandrel. Helical microstructures made of multifunctional materials (e.g., carbon nanotube nanocomposites, metallic coated polymer template) were used in different technological applications such as strain/load sensors, cell separators and micro-antennas. These innovative 3D microsystems exploiting the unique helix shape demonstrated their potential for better performance and more compact microsystems.
Gas Hydrate Petroleum System Modeling in western Nankai Trough Area
NASA Astrophysics Data System (ADS)
Tanaka, M.; Aung, T. T.; Fujii, T.; Wada, N.; Komatsu, Y.
2017-12-01
Since 2003, we have been conducting Gas Hydrate (GH) petroleum system models covering the eastern Nankai Trough, Japan, and results of resource potential from regional model shows good match with the value depicted from seismic and log data. In this year, we have applied this method to explore GH potential in study area. In our study area, GH prospects have been identified with aid of bottom simulating reflector (BSR) and presence of high velocity anomalies above the BSR interpreted based on 3D migration seismic and high density velocity cubes. In order to understand the pathway of biogenic methane from source to GH prospects 1D-2D-3D GH petroleum system models are built and investigated. This study comprises lower Miocene to Pleistocene, deep to shallow marine sedimentary successions of Pliocene and Pleistocene layers overlain the basement. The BSR were interpreted in Pliocene and Pleistocene layers. Based on 6 interpreted sequence boundaries from 3D migration seismic and velocity data, construction of a depth 3D framework model is made and distributed by a conceptual submarine fan depositional facies model derived from seismic facies analysis and referring existing geological report. 1D models are created to analyze lithology sensitivity to temperature and vitrinite data from an exploratory well drilled in the vicinity of study area. The PSM parameters are applied in 2D and 3D modeling and simulation. Existing report of the explanatory well reveals that thermogenic origin are considered to exist. For this reason, simulation scenarios including source formations for both biogenic and thermogenic reaction models are also investigated. Simulation results reveal lower boundary of GH saturation zone at pseudo wells has been simulated with sensitivity of a few tens of meters in comparing with interpreted BSR. From sensitivity analysis, simulated temperature was controlled by different peak generation temperature models and geochemical parameters. Progressive folding and updipping layers including paleostructure can effectively assist biogenic gas migration to upward. Biogenic and Thermogenic mixing model shows that kitchen center only has a potential for generating thermogenic hydrocarbon. Our Prospect based on seismic interpretation is consistent with high GH saturation area based on 3D modeling results.
A novel 3D-printed hybrid simulation model for robotic-assisted kidney transplantation (RAKT).
Uwechue, Raphael; Gogalniceanu, Petrut; Kessaris, Nicos; Byrne, Nick; Chandak, Pankaj; Olsburgh, Jonathon; Ahmed, Kamran; Mamode, Nizam; Loukopoulos, Ioannis
2018-01-27
Robotic-assisted kidney transplantation (RAKT) offers key benefits for patients that have been demonstrated in several studies. A barrier to the wider uptake of RAKT is surgical skill acquisition. This is exacerbated by the challenges of modern surgery with reduced surgical training time, patient safety concerns and financial pressures. Simulation is a well-established method of developing surgical skill in a safe and controlled environment away from the patient. We have developed a 3D printed simulation model for the key step of the kidney transplant operation which is the vascular anastomosis. The model is anatomically accurate, based on the CT scans of patients and it incorporates deceased donor vascular tissue. Crucially, it was developed to be used in the robotic operating theatre with the operating robot to enhance its fidelity. It is portable and relatively inexpensive when compared with other forms of simulation such as virtual reality or animal lab training. It thus has the potential of being more accessible as a training tool for the safe acquisition of RAKT specific skills. We demonstrate this model here.
24 CFR 35.300 - Purpose and applicability.
Code of Federal Regulations, 2010 CFR
2010-04-01
... Development LEAD-BASED PAINT POISONING PREVENTION IN CERTAIN RESIDENTIAL STRUCTURES Project-Based Assistance... D is to establish procedures to eliminate as far as practicable lead-based paint hazards in a...
24 CFR 35.300 - Purpose and applicability.
Code of Federal Regulations, 2011 CFR
2011-04-01
... Development LEAD-BASED PAINT POISONING PREVENTION IN CERTAIN RESIDENTIAL STRUCTURES Project-Based Assistance... D is to establish procedures to eliminate as far as practicable lead-based paint hazards in a...
24 CFR 35.300 - Purpose and applicability.
Code of Federal Regulations, 2014 CFR
2014-04-01
... Development LEAD-BASED PAINT POISONING PREVENTION IN CERTAIN RESIDENTIAL STRUCTURES Project-Based Assistance... D is to establish procedures to eliminate as far as practicable lead-based paint hazards in a...
24 CFR 35.300 - Purpose and applicability.
Code of Federal Regulations, 2013 CFR
2013-04-01
... Development LEAD-BASED PAINT POISONING PREVENTION IN CERTAIN RESIDENTIAL STRUCTURES Project-Based Assistance... D is to establish procedures to eliminate as far as practicable lead-based paint hazards in a...
24 CFR 35.300 - Purpose and applicability.
Code of Federal Regulations, 2012 CFR
2012-04-01
... Development LEAD-BASED PAINT POISONING PREVENTION IN CERTAIN RESIDENTIAL STRUCTURES Project-Based Assistance... D is to establish procedures to eliminate as far as practicable lead-based paint hazards in a...
Technical Note: A 3-D rendering algorithm for electromechanical wave imaging of a beating heart.
Nauleau, Pierre; Melki, Lea; Wan, Elaine; Konofagou, Elisa
2017-09-01
Arrhythmias can be treated by ablating the heart tissue in the regions of abnormal contraction. The current clinical standard provides electroanatomic 3-D maps to visualize the electrical activation and locate the arrhythmogenic sources. However, the procedure is time-consuming and invasive. Electromechanical wave imaging is an ultrasound-based noninvasive technique that can provide 2-D maps of the electromechanical activation of the heart. In order to fully visualize the complex 3-D pattern of activation, several 2-D views are acquired and processed separately. They are then manually registered with a 3-D rendering software to generate a pseudo-3-D map. However, this last step is operator-dependent and time-consuming. This paper presents a method to generate a full 3-D map of the electromechanical activation using multiple 2-D images. Two canine models were considered to illustrate the method: one in normal sinus rhythm and one paced from the lateral region of the heart. Four standard echographic views of each canine heart were acquired. Electromechanical wave imaging was applied to generate four 2-D activation maps of the left ventricle. The radial positions and activation timings of the walls were automatically extracted from those maps. In each slice, from apex to base, these values were interpolated around the circumference to generate a full 3-D map. In both cases, a 3-D activation map and a cine-loop of the propagation of the electromechanical wave were automatically generated. The 3-D map showing the electromechanical activation timings overlaid on realistic anatomy assists with the visualization of the sources of earlier activation (which are potential arrhythmogenic sources). The earliest sources of activation corresponded to the expected ones: septum for the normal rhythm and lateral for the pacing case. The proposed technique provides, automatically, a 3-D electromechanical activation map with a realistic anatomy. This represents a step towards a noninvasive tool to efficiently localize arrhythmias in 3-D. © 2017 American Association of Physicists in Medicine.
Somoskeöy, Szabolcs; Tunyogi-Csapó, Miklós; Bogyó, Csaba; Illés, Tamás
2012-10-01
For many decades, visualization and evaluation of three-dimensional (3D) spinal deformities have only been possible by two-dimensional (2D) radiodiagnostic methods, and as a result, characterization and classification were based on 2D terminologies. Recent developments in medical digital imaging and 3D visualization techniques including surface 3D reconstructions opened a chance for a long-sought change in this field. Supported by a 3D Terminology on Spinal Deformities of the Scoliosis Research Society, an approach for 3D measurements and a new 3D classification of scoliosis yielded several compelling concepts on 3D visualization and new proposals for 3D classification in recent years. More recently, a new proposal for visualization and complete 3D evaluation of the spine by 3D vertebra vectors has been introduced by our workgroup, a concept, based on EOS 2D/3D, a groundbreaking new ultralow radiation dose integrated orthopedic imaging device with sterEOS 3D spine reconstruction software. Comparison of accuracy, correlation of measurement values, intraobserver and interrater reliability of methods by conventional manual 2D and vertebra vector-based 3D measurements in a routine clinical setting. Retrospective, nonrandomized study of diagnostic X-ray images created as part of a routine clinical protocol of eligible patients examined at our clinic during a 30-month period between July 2007 and December 2009. In total, 201 individuals (170 females, 31 males; mean age, 19.88 years) including 10 healthy athletes with normal spine and patients with adolescent idiopathic scoliosis (175 cases), adult degenerative scoliosis (11 cases), and Scheuermann hyperkyphosis (5 cases). Overall range of coronal curves was between 2.4 and 117.5°. Analysis of accuracy and reliability of measurements was carried out on a group of all patients and in subgroups based on coronal plane deviation: 0 to 10° (Group 1; n=36), 10 to 25° (Group 2; n=25), 25 to 50° (Group 3; n=69), 50 to 75° (Group 4; n=49), and above 75° (Group 5; n=22). All study subjects were examined by EOS 2D imaging, resulting in anteroposterior (AP) and lateral (LAT) full spine, orthogonal digital X-ray images, in standing position. Conventional coronal and sagittal curvature measurements including sagittal L5 vertebra wedges were determined by 3 experienced examiners, using traditional Cobb methods on EOS 2D AP and LAT images. Vertebra vector-based measurements were performed as published earlier, based on computer-assisted calculations of corresponding spinal curvature. Vertebra vectors were generated by dedicated software from sterEOS 3D spine models reconstructed from EOS 2D images by the same three examiners. Manual measurements were performed by each examiner, thrice for sterEOS 3D reconstructions and twice for vertebra vector-based measurements. Means comparison t test, Pearson bivariate correlation analysis, reliability analysis by intraclass correlation coefficients for intraobserver reproducibility and interrater reliability were performed using SPSS v16.0 software. In comparison with manual 2D methods, only small and nonsignificant differences were detectable in vertebra vector-based curvature data for coronal curves and thoracic kyphosis, whereas the found difference in L1-L5 lordosis values was shown to be strongly related to the magnitude of corresponding L5 wedge. Intraobserver reliability was excellent for both methods, and interrater reproducibility was consistently higher for vertebra vector-based methods that was also found to be unaffected by the magnitude of coronal curves or sagittal plane deviations. Vertebra vector-based angulation measurements could fully substitute conventional manual 2D measurements, with similar accuracy and higher intraobserver reliability and interrater reproducibility. Vertebra vectors represent a truly 3D solution for clear and comprehensible 3D visualization of spinal deformities while preserving crucial parametric information for vertebral size, 3D position, orientation, and rotation. The concept of vertebra vectors may serve as a starting point to a valid and clinically useful alternative for a new 3D classification of scoliosis. Copyright © 2012 Elsevier Inc. All rights reserved.
Computer Vision Assisted Virtual Reality Calibration
NASA Technical Reports Server (NTRS)
Kim, W.
1999-01-01
A computer vision assisted semi-automatic virtual reality (VR) calibration technology has been developed that can accurately match a virtual environment of graphically simulated three-dimensional (3-D) models to the video images of the real task environment.
Tsai, Tsung-Yuan; Li, Jing-Sheng; Wang, Shaobai; Li, Pingyue; Kwon, Young-Min; Li, Guoan
2013-01-01
The statistical shape model (SSM) method that uses 2D images of the knee joint to predict the 3D joint surface model has been reported in literature. In this study, we constructed a SSM database using 152 human CT knee joint models, including the femur, tibia and patella and analyzed the characteristics of each principal component of the SSM. The surface models of two in vivo knees were predicted using the SSM and their 2D bi-plane fluoroscopic images. The predicted models were compared to their CT joint models. The differences between the predicted 3D knee joint surfaces and the CT image-based surfaces were 0.30 ± 0.81 mm, 0.34 ± 0.79 mm and 0.36 ± 0.59 mm for the femur, tibia and patella, respectively (average ± standard deviation). The computational time for each bone of the knee joint was within 30 seconds using a personal computer. The analysis of this study indicated that the SSM method could be a useful tool to construct 3D surface models of the knee with sub-millimeter accuracy in real time. Thus it may have a broad application in computer assisted knee surgeries that require 3D surface models of the knee. PMID:24156375
Lledó, Luis D.; Díez, Jorge A.; Bertomeu-Motos, Arturo; Ezquerro, Santiago; Badesa, Francisco J.; Sabater-Navarro, José M.; García-Aracil, Nicolás
2016-01-01
Post-stroke neurorehabilitation based on virtual therapies are performed completing repetitive exercises shown in visual electronic devices, whose content represents imaginary or daily life tasks. Currently, there are two ways of visualization of these task. 3D virtual environments are used to get a three dimensional space that represents the real world with a high level of detail, whose realism is determinated by the resolucion and fidelity of the objects of the task. Furthermore, 2D virtual environments are used to represent the tasks with a low degree of realism using techniques of bidimensional graphics. However, the type of visualization can influence the quality of perception of the task, affecting the patient's sensorimotor performance. The purpose of this paper was to evaluate if there were differences in patterns of kinematic movements when post-stroke patients performed a reach task viewing a virtual therapeutic game with two different type of visualization of virtual environment: 2D and 3D. Nine post-stroke patients have participated in the study receiving a virtual therapy assisted by PUPArm rehabilitation robot. Horizontal movements of the upper limb were performed to complete the aim of the tasks, which consist in reaching peripheral or perspective targets depending on the virtual environment shown. Various parameter types such as the maximum speed, reaction time, path length, or initial movement are analyzed from the data acquired objectively by the robotic device to evaluate the influence of the task visualization. At the end of the study, a usability survey was provided to each patient to analysis his/her satisfaction level. For all patients, the movement trajectories were enhanced when they completed the therapy. This fact suggests that patient's motor recovery was increased. Despite of the similarity in majority of the kinematic parameters, differences in reaction time and path length were higher using the 3D task. Regarding the success rates were very similar. In conclusion, the using of 2D environments in virtual therapy may be a more appropriate and comfortable way to perform tasks for upper limb rehabilitation of post-stroke patients, in terms of accuracy in order to effectuate optimal kinematic trajectories. PMID:27616992
Registration of MRI to Intraoperative Radiographs for Target Localization in Spinal Interventions
De Silva, T; Uneri, A; Ketcha, M D; Reaungamornrat, S; Goerres, J; Jacobson, M W; Vogt, S; Kleinszig, G; Khanna, A J; Wolinsky, J-P; Siewerdsen, J H
2017-01-01
Purpose Decision support to assist in target vertebra localization could provide a useful aid to safe and effective spine surgery. Previous solutions have shown 3D-2D registration of preoperative CT to intraoperative radiographs to reliably annotate vertebral labels for assistance during level localization. We present an algorithm (referred to as MR-LevelCheck) to perform 3D-2D registration based on a preoperative MRI to accommodate the increasingly common clinical scenario in which MRI is used instead of CT for preoperative planning. Methods Straightforward adaptation of gradient/intensity-based methods appropriate to CT-to-radiograph registration is confounded by large mismatch and noncorrespondence in image intensity between MRI and radiographs. The proposed method overcomes such challenges with a simple vertebrae segmentation step using vertebra centroids as seed points (automatically defined within existing workflow). Forwards projections are computed using segmented MRI and registered to radiographs via gradient orientation (GO) similarity and the CMA-ES (Covariance-Matrix-Adaptation Evolutionary-Strategy) optimizer. The method was tested in an IRB-approved study involving 10 patients undergoing cervical, thoracic, or lumbar spine surgery following preoperative MRI. Results The method successfully registered each preoperative MRI to intraoperative radiographs and maintained desirable properties of robustness against image content mismatch and large capture range. Robust registration performance was achieved with projection distance error (PDE) (median ± iqr) = 4.3 ± 2.6 mm (median ± iqr) and 0% failure rate. Segmentation accuracy for the continuous max-flow method yielded Dice coefficient = 88.1 ± 5.2, Accuracy = 90.6 ± 5.7, RMSE = 1.8 ± 0.6 mm, and contour affinity ratio (CAR) = 0.82 ± 0.08. Registration performance was found to be robust for segmentation methods exhibiting RMSE < 3 mm and CAR > 0.50. Conclusion The MR-LevelCheck method provides a potentially valuable extension to a previously developed decision support tool for spine surgery target localization by extending its utility to preoperative MRI while maintaining characteristics of accuracy and robustness. PMID:28050972
Mansfield, Robert T; Lin, Kimberly Y; Zaoutis, Theoklis; Mott, Antonio R; Mohamad, Zeinab; Luan, Xianqun; Kaufman, Beth D; Ravishankar, Chitra; Gaynor, J William; Shaddy, Robert E; Rossano, Joseph W
2015-07-01
The use of ventricular assist devices has increased dramatically in adult heart failure patients. However, the overall use, outcome, comorbidities, and resource utilization of ventricular assist devices in pediatric patients have not been well described. We sought to demonstrate that the use of ventricular assist devices in pediatric patients has increased over time and that mortality has decreased. A retrospective study of the Pediatric Health Information System database was performed for patients 20 years old or younger undergoing ventricular assist device placement from 2000 to 2010. None. Four hundred seventy-five pediatric patients were implanted with ventricular assist devices during the study period: 69 in 2000-2003 (era 1), 135 in 2004-2006 (era 2), and 271 in 2007-2010 (era 3). Median age at ventricular assist device implantation was 6.0 years (interquartile range, 0.5-13.8), and the proportion of children who were 1-12 years old increased from 29% in era 1 to 47% in era 3 (p = 0.002). The majority of patients had a diagnosis of cardiomyopathy; this increased from 52% in era 1 to 72% in era 3 (p = 0.003). Comorbidities included arrhythmias (48%), pulmonary hypertension (16%), acute renal failure (34%), cerebrovascular disease (28%), and sepsis/systemic inflammatory response syndrome (34%). Two hundred forty-seven patients (52%) underwent heart transplantation and 327 (69%) survived to hospital discharge. Hospital mortality decreased from 42% in era 1 to 25% in era 3 (p = 0.004). Median hospital length of stay increased (37 d [interquartile range, 12-64 d] in era 1 vs 69 d [interquartile range, 35-130] in era 3; p < 0.001) and median adjusted hospital charges increased ($630,630 [interquartile range, $227,052-$853,318] in era 1 vs $1,577,983 [interquartile range, $874,463-$2,280,435] in era 3; p < 0.001). Factors associated with increased mortality include age less than 1 year (odds ratio, 2.04; 95% CI, 1.01-3.83), acute renal failure (odds ratio, 2.1; 95% CI, 1.26-3.65), cerebrovascular disease (odds ratio, 2.1; 95% CI, 1.25-3.62), and extracorporeal membrane oxygenation (odds ratio, 3.16; 95% CI, 1.79-5.60). Ventricular assist device placement in era 3 (odds ratio, 0.3; 95% CI, 0.15-0.57) and a diagnosis of cardiomyopathy (odds ratio, 0.5; 95% CI, 0.32-0.84), were associated with decreased mortality. Large-volume centers had lower mortality (odds ratio, 0.55; 95% CI, 0.34-0.88), lower use of extracorporeal membrane oxygenation, and higher charges. The use of ventricular assist devices and survival after ventricular assist device placement in pediatric patients have increased over time, with a concomitant increase in resource utilization. Age under 1 year, certain noncardiac morbidities, and the use of extracorporeal membrane oxygenation are associated with worse outcomes. Lower mortality was seen at larger volume ventricular assist device centers.
Haptic computer-assisted patient-specific preoperative planning for orthopedic fractures surgery.
Kovler, I; Joskowicz, L; Weil, Y A; Khoury, A; Kronman, A; Mosheiff, R; Liebergall, M; Salavarrieta, J
2015-10-01
The aim of orthopedic trauma surgery is to restore the anatomy and function of displaced bone fragments to support osteosynthesis. For complex cases, including pelvic bone and multi-fragment femoral neck and distal radius fractures, preoperative planning with a CT scan is indicated. The planning consists of (1) fracture reduction-determining the locations and anatomical sites of origin of the fractured bone fragments and (2) fracture fixation-selecting and placing fixation screws and plates. The current bone fragment manipulation, hardware selection, and positioning processes based on 2D slices and a computer mouse are time-consuming and require a technician. We present a novel 3D haptic-based system for patient-specific preoperative planning of orthopedic fracture surgery based on CT scans. The system provides the surgeon with an interactive, intuitive, and comprehensive, planning tool that supports fracture reduction and fixation. Its unique features include: (1) two-hand haptic manipulation of 3D bone fragments and fixation hardware models; (2) 3D stereoscopic visualization and multiple viewing modes; (3) ligaments and pivot motion constraints to facilitate fracture reduction; (4) semiautomatic and automatic fracture reduction modes; and (5) interactive custom fixation plate creation to fit the bone morphology. We evaluate our system with two experimental studies: (1) accuracy and repeatability of manual fracture reduction and (2) accuracy of our automatic virtual bone fracture reduction method. The surgeons achieved a mean accuracy of less than 1 mm for the manual reduction and 1.8 mm (std [Formula: see text] 1.1 mm) for the automatic reduction. 3D haptic-based patient-specific preoperative planning of orthopedic fracture surgery from CT scans is useful and accurate and may have significant advantages for evaluating and planning complex fractures surgery.
Gas Sensors Based on One Dimensional Nanostructured Metal-Oxides: A Review
Arafat, M. M.; Dinan, B.; Akbar, Sheikh A.; Haseeb, A. S. M. A.
2012-01-01
Recently one dimensional (1-D) nanostructured metal-oxides have attracted much attention because of their potential applications in gas sensors. 1-D nanostructured metal-oxides provide high surface to volume ratio, while maintaining good chemical and thermal stabilities with minimal power consumption and low weight. In recent years, various processing routes have been developed for the synthesis of 1-D nanostructured metal-oxides such as hydrothermal, ultrasonic irradiation, electrospinning, anodization, sol-gel, molten-salt, carbothermal reduction, solid-state chemical reaction, thermal evaporation, vapor-phase transport, aerosol, RF sputtering, molecular beam epitaxy, chemical vapor deposition, gas-phase assisted nanocarving, UV lithography and dry plasma etching. A variety of sensor fabrication processing routes have also been developed. Depending on the materials, morphology and fabrication process the performance of the sensor towards a specific gas shows a varying degree of success. This article reviews and evaluates the performance of 1-D nanostructured metal-oxide gas sensors based on ZnO, SnO2, TiO2, In2O3, WOx, AgVO3, CdO, MoO3, CuO, TeO2 and Fe2O3. Advantages and disadvantages of each sensor are summarized, along with the associated sensing mechanism. Finally, the article concludes with some future directions of research. PMID:22969344
Design Mining Interacting Wind Turbines.
Preen, Richard J; Bull, Larry
2016-01-01
An initial study has recently been presented of surrogate-assisted evolutionary algorithms used to design vertical-axis wind turbines wherein candidate prototypes are evaluated under fan-generated wind conditions after being physically instantiated by a 3D printer. Unlike other approaches, such as computational fluid dynamics simulations, no mathematical formulations were used and no model assumptions were made. This paper extends that work by exploring alternative surrogate modelling and evolutionary techniques. The accuracy of various modelling algorithms used to estimate the fitness of evaluated individuals from the initial experiments is compared. The effect of temporally windowing surrogate model training samples is explored. A surrogate-assisted approach based on an enhanced local search is introduced; and alternative coevolution collaboration schemes are examined.
[Virtual reality in video-assisted thoracoscopic lung segmentectomy].
Onuki, Takamasa
2009-07-01
The branching patterns of pulmonary arteries and veins vary greatly in the pulmonary hilar region and are very complicated. We attempted to reconstruct anatomically correct images using a freeware program. After uploading the images to a personal computer, bronchi, pulmonary arteries and veins were traced by moving up and down in the images and the location and thickness of the bronchi and pulmonary vasculture were indicated as different-sized cylinders. Next, based on the resulting numerical data, a 3D image was reconstructed using Metasequoia shareware. The reconstructed images can be manipulated by virtual surgical procedures such as reshaping, cutting and moving. These system would be very helpful in complicated video-assisted thoracic surgery such as lung segmentectomy.
Reversible Shape Memory Polymers and Composites: Synthesis, Modeling and Design
2013-03-01
Polymer; and (iii) Development of a Shape Memory Assisted Self - Healing Polymer. Page 3 of 19 Mather/FA9550-09-1-0195 IV(i) Modeling and Model...0195 IV(iii) Development of a Shape Memory Assisted Self - Healing Polymer Erika D. Rodriguez, X. Luo, and P.T. Mather, “Linear and Crosslinked...Poly (ε- Caprolactone) Polymers for Shape Memory Assisted Self - Healing (SMASH),” ACS Applied Materials and Interfaces 3 152-161 (2011). Self
NASA Astrophysics Data System (ADS)
Zhang, Xiang; Shi, Chunsheng; Liu, Enzuo; Li, Jiajun; Zhao, Naiqin; He, Chunnian
2015-10-01
In this study, we demonstrated nitrogen-doped graphene network supported few-layered graphene shell encapsulated Cu nanoparticles (NPs) (Cu@G-NGNs) as a sensing platform, which were constructed by a simple and scalable in situ chemical vapor deposition (CVD) technique with the assistance of a self-assembled three-dimensional (3D) NaCl template. Compared with pure Cu NPs and graphene decorated Cu NPs, the graphene shells can strengthen the plasmonic coupling between graphene and Cu, thereby contributing to an obvious improvement in the local electromagnetic field that was validated by finite element numerical simulations, while the 3D nitrogen-doped graphene walls with a large surface area facilitated molecule adsorption and the doped nitrogen atoms embedded in the graphene lattice can reduce the surface energy of the system. With these merits, a good surface enhanced Raman spectroscopy (SERS) activity of the 3D Cu@G-NGN painting film on glass was demonstrated using rhodamine 6G and crystal violet as model analytes, exhibiting a satisfactory sensitivity, reproducibility and stability. As far as we know, this is the first report on the in situ synthesis of nitrogen-doped graphene/copper nanocomposites and this facile and low-cost Cu-based strategy tends to be a good supplement to Ag and Au based substrates for SERS applications.In this study, we demonstrated nitrogen-doped graphene network supported few-layered graphene shell encapsulated Cu nanoparticles (NPs) (Cu@G-NGNs) as a sensing platform, which were constructed by a simple and scalable in situ chemical vapor deposition (CVD) technique with the assistance of a self-assembled three-dimensional (3D) NaCl template. Compared with pure Cu NPs and graphene decorated Cu NPs, the graphene shells can strengthen the plasmonic coupling between graphene and Cu, thereby contributing to an obvious improvement in the local electromagnetic field that was validated by finite element numerical simulations, while the 3D nitrogen-doped graphene walls with a large surface area facilitated molecule adsorption and the doped nitrogen atoms embedded in the graphene lattice can reduce the surface energy of the system. With these merits, a good surface enhanced Raman spectroscopy (SERS) activity of the 3D Cu@G-NGN painting film on glass was demonstrated using rhodamine 6G and crystal violet as model analytes, exhibiting a satisfactory sensitivity, reproducibility and stability. As far as we know, this is the first report on the in situ synthesis of nitrogen-doped graphene/copper nanocomposites and this facile and low-cost Cu-based strategy tends to be a good supplement to Ag and Au based substrates for SERS applications. Electronic supplementary information (ESI) available. See DOI: 10.1039/c5nr04259c
Parchi, Paolo Domenico; Ferrari, Vincenzo; Piolanti, Nicola; Andreani, Lorenzo; Condino, Sara; Evangelisti, Gisberto; Lisanti, Michele
2013-09-01
Each year approximately 1 million total hip replacements (THR) are performed worldwide. A percentage of failure due to surgical approach and imprecise implant placement still exists. These result in several serious complications. We propose an approach to plan, to simulate, and to assist prosthesis implantation for difficult cases of THR based on 3-D virtual models, generated by segmenting patients' CT images, 3-D solid models, obtained by rapid prototyping (RP), and virtual procedure simulation. We carried out 8 THR with the aid of 3-D reconstruction and RP. After each procedure a questionnaire was submitted to the surgeon to assess the perceived added value of the technology. In all cases, the surgeon evaluated the 3-D model as useful in order to perform the planning. The clinical results showed a mean increase in the Harris Hip Score of about 42.5 points. The mean time of prototyping was 7.3 hours, (min 3.5 hours, max 9.3 hours). The mean surgery time was 65 minutes (min 50 minutes, max 88 minutes). Our study suggests that meticulous preoperative planning is necessary in front of a great aberration of the joint and in absence of normal anatomical landmarks, CT scan is mandatory, and 3-D reconstruction with solid model is useful.
Customized Fabrication of Osteochondral Tissue for Articular Joint Surface Repair
2016-09-01
differentiation cues for chondrogenesis and osteogenesis, by the 3D printing method of projection stereolithography (PSL). We further test the...military medical care costs. Post Traumatic Osteoarthritis, Injury, Articular Cartilage, tissue-engineered, 3D printing , Osteochondral constructs. Major...tissue with the stem cells used. He will also be assisting with the 3D printing of the material. Funding Support: Supported by internal University
NASA Astrophysics Data System (ADS)
Zuhrie, M. S.; Basuki, I.; Asto B, I. G. P.; Anifah, L.
2018-01-01
The focus of the research is the teaching module which incorporates manufacturing, planning mechanical designing, controlling system through microprocessor technology and maneuverability of the robot. Computer interactive and computer-assisted learning is strategies that emphasize the use of computers and learning aids (computer assisted learning) in teaching and learning activity. This research applied the 4-D model research and development. The model is suggested by Thiagarajan, et.al (1974). 4-D Model consists of four stages: Define Stage, Design Stage, Develop Stage, and Disseminate Stage. This research was conducted by applying the research design development with an objective to produce a tool of learning in the form of intelligent robot modules and kit based on Computer Interactive Learning and Computer Assisted Learning. From the data of the Indonesia Robot Contest during the period of 2009-2015, it can be seen that the modules that have been developed confirm the fourth stage of the research methods of development; disseminate method. The modules which have been developed for students guide students to produce Intelligent Robot Tool for Teaching Based on Computer Interactive Learning and Computer Assisted Learning. Results of students’ responses also showed a positive feedback to relate to the module of robotics and computer-based interactive learning.
Campos, M; Perruchon, C; Karas, P A; Karavasilis, D; Diez, M C; Karpouzas, D G
2017-02-01
Biobeds are on-farm biodepuration systems whose efficiency rely on their high pesticide biodegradation capacity. We evaluated two optimization strategies, bioaugmentation and/or rhizosphere-assisted biodegradation, to maximize the dissipation capacity of biobeds. Iprodione was used as a model pesticide. Its dissipation and metabolism was determined in a biobed packing material inoculated with an iprodione-degrading Arthrobacter strain C1 (bioaugmentation, treatments B+C1) and/or seeded with ryegrass (rhizosphere-assisted biodegradation, treatments B+P). The impact of those strategies on the activity and composition of the microbial community was determined. Bioaugmentation accelerated the dissipation of iprodione which was further enhanced in the bioaugmented, rhizosphere-assisted treatment (treatment B+P+C1, Half-life (DT 50 ) = 3.4 d), compared to the non-bioaugmented, non rhizosphere-assisted control (DT 50 = 9.5 d, treatment B). Bioaugmentation resulted in the earlier formation of intermediate formation of metabolites I (3,5-dichlorophenyl-carboxamide), II (3,5-dichlorophenylurea acetate) and 3,5-dichloroaniline (3,5-DCA). The latter was further dissipated by the indigenous microbial community. Acid phosphatase (AP) and β-glucosidase (GLU) were temporarily stimulated in rhizosphere-assisted treatments, whereas a stimulation of the fluorescein diacetate (FDA) hydrolytic activity in the bioaugmented treatments coincided with the hydrolysis of iprodione. q-PCR showed that changes in the abundance of alpha-proteobacteria and firmicutes was driven by the presence of rhizosphere while bioaugmentation had no significant effect. Copyright © 2016 Elsevier Ltd. All rights reserved.
Li, Wei Zhong; Zhang, Mei Chao; Li, Shao Ping; Zhang, Lei Tao; Huang, Yu
2009-06-01
With the advent of CAD/CAM and rapid prototyping (RP), a technical revolution in oral and maxillofacial trauma was promoted to benefit treatment, repair of maxillofacial fractures and reconstruction of maxillofacial defects. For a patient with zygomatico-facial collapse deformity resulting from a zygomatico-orbito-maxillary complex (ZOMC) fracture, CT scan data were processed by using Mimics 10.0 for three-dimensional (3D) reconstruction. The reduction design was aided by 3D virtual imaging and the 3D skull model was reproduced using the RP technique. In line with the design by Mimics, presurgery was performed on the 3D skull model and the semi-coronal incision was taken for reduction of ZOMC fracture, based on the outcome from the presurgery. Postoperative CT and images revealed significantly modified zygomatic collapse and zygomatic arch rise and well-modified facial symmetry. The CAD/CAM and RP technique is a relatively useful tool that can assist surgeons with reconstruction of the maxillofacial skeleton, especially in repairs of ZOMC fracture.
Gelatin methacrylamide hydrogel with graphene nanoplatelets for neural cell-laden 3D bioprinting.
Wei Zhu; Harris, Brent T; Zhang, Lijie Grace
2016-08-01
Nervous system is extremely complex which leads to rare regrowth of nerves once injury or disease occurs. Advanced 3D bioprinting strategy, which could simultaneously deposit biocompatible materials, cells and supporting components in a layer-by-layer manner, may be a promising solution to address neural damages. Here we presented a printable nano-bioink composed of gelatin methacrylamide (GelMA), neural stem cells, and bioactive graphene nanoplatelets to target nerve tissue regeneration in the assist of stereolithography based 3D bioprinting technique. We found the resultant GelMA hydrogel has a higher compressive modulus with an increase of GelMA concentration. The porous GelMA hydrogel can provide a biocompatible microenvironment for the survival and growth of neural stem cells. The cells encapsulated in the hydrogel presented good cell viability at the low GelMA concentration. Printed neural construct exhibited well-defined architecture and homogenous cell distribution. In addition, neural stem cells showed neuron differentiation and neurites elongation within the printed construct after two weeks of culture. These findings indicate the 3D bioprinted neural construct has great potential for neural tissue regeneration.
Dolati, Parviz; Eichberg, Daniel; Golby, Alexandra; Zamani, Amir; Laws, Edward
2016-01-01
Introduction Transsphenoidal surgery (TSS) is a well-known approach for the treatment of pituitary tumors. However, lateral misdirection and vascular damage, intraoperative CSF leakage, and optic nerve and vascular injuries are all well-known complications, and the risk of adverse events is more likely in less experienced hands. This prospective study was conducted to validate the accuracy of image-based segmentation in localization of neurovascular structures during TSS. Methods Twenty-five patients with pituitary tumors underwent preoperative 3TMRI, which included thin-sectioned 3D space T2, 3D Time of Flight and MPRAGE sequences. Images were reviewed by an expert independent neuroradiologist. Imaging sequences were loaded in BrainLab iPlanNet (16/25 cases) or Stryker (9/25 cases) image guidance platforms for segmentation and pre-operative planning. After patient registration into the neuronavigation system and subsequent surgical exposure, each segmented neural or vascular element was validated by manual placement of the navigation probe on or as close as possible to the target. The audible pulsations of the bilateral ICA were confirmed using a micro-Doppler probe. Results Pre-operative segmentation of the ICA and cavernous sinus matched with the intra-operative endoscopic and micro-Doppler findings in all cases (Dice Similarity Coefficient =1). This information reassured the surgeons with regard to the lateral extent of bone removal at the sellar floor and the limits of lateral exploration. Excellent correspondence between image-based segmentation and the endoscopic view was also evident at the surface of the tumor and at the tumor-normal gland interfaces. This assisted in preventing unnecessary removal of the normal pituitary gland. Image-guidance assisted the surgeons in localizing the optic nerve and chiasm in 64% of the cases and the diaphragma sella in 52% of cases, which helped to determine the limits of upward exploration and to decrease the risk of CSF leakage. The accuracy of the measurements was 1.20 + 0.21 mm (mean +/−SD). Conclusion Image-based pre-operative vascular and neural element segmentation, especially with 3D reconstruction, is highly informative preoperatively and potentially could assist less experienced neurosurgeons in preventing vascular and neural injury during TSS. Additionally, the accuracy found in this study is comparable to previously reported neuronavigation measurements. This novel preliminary study is encouraging for future prospective intraoperative validation with larger numbers of patients. PMID:27302558
Kim, Myeong-Seong; Kim, Hyun-Kyung; Lee, Suk-Woo; Kim, Dong-Hyun; Ruan, Dianbo; Chung, Kyung Yoon; Lee, Sang Hyun; Roh, Kwang Chul; Kim, Kwang-Bum
2016-01-01
Microsized, spherical, three-dimensional (3D) graphene-based composites as electrode materials exhibit improved tap density and electrochemical properties. In this study, we report 3D LiMn0.75Fe0.25PO4/reduced graphene oxide microspheres synthesized by one-step salt-assisted spray drying using a mixed solution containing a precursor salt and graphene oxide and a subsequent heat treatment. During this process, it was found that the type of metal salt used has significant effects on the morphology, phase purity, and electrochemical properties of the synthesized samples. Furthermore, the amount of the chelating agent used also affects the phase purity and electrochemical properties of the samples. The composite exhibited a high tap density (1.1 g cm−3) as well as a gravimetric capacity of 161 mA h g−1 and volumetric capacity of 281 mA h cm−3 at 0.05 C-rate. It also exhibited excellent rate capability, delivering a discharge capacity of 90 mA h g−1 at 60 C-rate. Furthermore, the microspheres exhibited high energy efficiency and good cyclability, showing a capacity retention rate of 93% after 1000 cycles at 10 C-rate. PMID:27220812
13 CFR 125.3 - What types of subcontracting assistance are available to small businesses?
Code of Federal Regulations, 2014 CFR
2014-01-01
... controlled by women. The subcontracting assistance program implements section 8(d) of the Small Business Act... percentage of total contract dollars. (3) A prime contractor has a history of unjustified untimely or reduced... disadvantaged business, or women-owned small business; and (ix) As a best practice, the contractor may provide...
7 CFR 3570.61 - Eligibility for grant assistance
Code of Federal Regulations, 2010 CFR
2010-01-01
... grant assistance The essential community facility must primarily serve rural areas, be located in a.... Essential community facilities must be: (1) Located in rural areas, except for utility-type services, such.... (d) Economic feasibility. All projects financed under the provisions of this section must be based on...
Frequency Comb Assisted IR Measurements of H_3^+, H_2D^+ and D_2H^+ Transitions
NASA Astrophysics Data System (ADS)
Jusko, Pavol; Asvany, Oskar; Schlemmer, Stephan
2016-06-01
We present recent measurements of the fundamental transitions of H_3^+, H_2D^+ and D_2H^+ in a 4 K 22-pole trap by action spectroscopic techniques. Either Laser Induced Inhibition of Cluster Growth (He attachment at T≈4 K), endothermic reaction of H_3^+ with O_2, or deuterium exchange has been used as measurement scheme. We used a 3 μm optical parametric oscillator coupled to a frequency comb in order to achieve accuracy generally below 1 MHz. Five transitions of H_3^+, eleven of H_2D^+ and ten of D_2H^+ were recorder in our spectral range. We compare our H_3^+ results with two previous frequency comb assisted works. Moreover, accurate determination of the frequency allows us to predict pure rotational transitions for H_2D^+ and D_2H^+ in the THz range. P. Jusko, C. Konietzko, S. Schlemmer, O. Asvany, J. Mol. Spec. 319 (2016) 55 O. Asvany, S. Brünken, L. Kluge, S. Schlemmer, Appl. Phys. B 114 (2014) 203 O. Asvany, J. Krieg, S. Schlemmer, Rev. Sci. Instr. 83 (2012) 093110 J.N. Hodges, A.J. Perry, P.A. Jenkins, B.M. Siller, B.J. McCall, J. Chem. Phys. 139 (2013) 164201 H.-C. Chen, C.-Y. Hsiao, J.-L. Peng, T. Amano, J.-T. Shy, Phys. Rev. Lett. 109 (2012) 263002
Kim, Soodong; Sung, Gyung Tak
2018-03-27
Although nerve-sparing robot-assisted radical prostatectomy (NS-RALP) is performed, a large number of patients still experience erectile dysfunction (ED) after surgery. To evaluate the efficacy and safety of tadalafil 5 mg once daily (OaD) in ED treatment over 2 years and investigate the cause of vascular ED after NS-RARP. We retrospectively evaluated 95 men who underwent NS-RARP and had a penile rehabilitation treatment with tadalafil 5 mg OaD. They were classified into 3 groups: tadalafil 5 mg OaD for 2 years (group I), tadalafil 5 mg OaD for 1 year (group II), and no tadalafil (group III). All patients in group I underwent penile color duplex ultrasound to evaluate the cause of vascular ED. Patients were surveyed using the abridged 5-item International Index of Erectile Function (IIEF-5). Statistically significant improvements were observed in group I for all IIEF-5 domain scores (P = .000). There was no statistically significant difference in recovery of erectile function (EF) the 2-year follow-up between groups I and II. Sub-analysis based on NS status showed no difference in recovery of EF. However, group I showed better trends in EF improvement. Those with venogenic ED had poor responses compared with those with arteriogenic ED or unremarkable findings with tadalafil 5-mg OaD treatment (14.2% vs 55.0% vs 53.3%). The overall side effects included hot flushing in 9.5%, headache in 7.1%, and dizziness in 2.3% of patients. Long-term usage of tadalafil 5 mg OaD after RARP can be an effective option for penile rehabilitation. The present study is a retrospective study with a relatively small sample. Although the responses of patients with venogenic ED were limited compared with those with arteriogenic ED, tadalafil 5-mg OaD treatment was well tolerated and significantly improved EF up to 2 years after NS-RARP. Kim S, Sung GT. Efficacy and Safety of Tadalafil 5 mg Once Daily for the Treatment of Erectile Dysfunction After Robot-Assisted Laparoscopic Radical Prostatectomy: A 2-Year Follow-Up. Sex Med 2018;X:XXX-XXX. Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.
Caimmi, Marco; Chiavenna, Andrea; Scano, Alessandro; Gasperini, Giulio; Giovanzana, Chiara; Molinari Tosatti, Lorenzo; Molteni, Franco
2017-06-01
Robotic rehabilitation is promising to promote function in stroke patients. The assist as needed training paradigm has shown to stimulate neuroplasticity but often cannot be used because stroke patients are too impaired to actively control the robot against gravity. To verify whether a rehabilitation intervention based on robot fully assisted reaching against gravity (RCH) and hand-to-mouth (HTM) can promote upper-limb function in chronic stroke. Cohort study. Chronic stroke outpatients referring to the robotic rehabilitation lab of a rehabilitation centre. Ten chronic stroke patients with mild to moderate upper-limb hemiparesis. Patients underwent 12 sessions (3 per week) of robotic treatment using an end-effector robot Every session consisted of 20 minutes each of RCH and HtM; movements were fully assisted, but patients were asked to try to actively participate. The Fugl-Meyer Assessment (FMA) was the primary outcome measure; Medical Research Council and Modified Ashworth Scale were the secondary outcome measures. All patients, but one, show functional improvements (FMA section A-D, mean increment 7.2±3.9 points, P<0.008). This preliminary study shows that a robotic intervention based on functional movements, fully assisted, can be effective in promoting function in chronic stroke patients. These results are promising considering the short time of the intervention (1 month) and the time from the stroke event, which was large (27±20 months). A larger study, comprehensive of objective instrumental measures, is necessary to confirm the results. This intervention could be extended even to subacute stroke and other neurological disorders.
ArchE - An Architecture Design Assistant
2007-08-02
Architecture Design Assistant Len Bass August 2, 2007 Report Documentation Page Form ApprovedOMB No. 0704-0188 Public reporting burden for the...ArchE - An Architecture Design Assistant 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d. PROJECT NUMBER 5e. TASK...X, Module X 3 Author / Presenter, Date if Needed What is ArchE? ArchE is a software architecture design assistant, which: • Takes quality and
Low lift-to-drag aero-assisted orbit transfer vehicles
NASA Technical Reports Server (NTRS)
Andrews, D. G.; Savage, R. T.
1984-01-01
The results of systems analysis conducted on low life drag ratio (L/D) aero-assisted orbit transfer vehicle (AOTV's) are presented. The objectives for this class of vehicle and formulate technology development plans and funding levels to bring the required technologies to readiness levels, as well as develop a credible decision data base encompassing the entire range of low L/D concepts for use in future NASA Aeroassist Orbit Transfer Vehicles studies. Each candidate low L/D concept, the aerobrake, the lifting brake, and the aeromaneuvering concept could be made to work with technologies achievable by the early 1990's. All concepts require flexible structure with flexible thermal protection system (TPS) to be successfully integrated into the shuttle orbiter for launch, all required improvements in guidance and control to fly the dispersed atmospheres at high altitude, and all concepts had potential to evolve from ground-based to space-based operations.
3-D periodic mesoporous nickel oxide for nonenzymatic uric acid sensors with improved sensitivity
NASA Astrophysics Data System (ADS)
Huang, Wei; Cao, Yang; Chen, Yong; Zhou, Yang; Huang, Qingyou
2015-12-01
3-D periodic mesoporous nickel oxide (NiO) particles with crystalline walls have been synthesized through the microwave-assisted hard template route toward the KIT-6 silica. It was investigated as a nonenzymatic amperometric sensor for the detection of uric acid. 3-D periodic nickel oxide matrix has been obtained by the hard template route from the KIT-6 silica template. The crystalline nickel oxide belonged to the Ia3d space group, and its structure was characterized by X-ray diffraction (XRD), N2 adsorption-desorption, and transmission electron microscopy (TEM). The analysis results showed that the microwave-assisted mesoporous NiO materials were more appropriate to be electrochemical sensors than the traditional mesoporous NiO. Cyclic voltammetry (CV) revealed that 3-D periodic NiO exhibited a direct electrocatalytic activity for the oxidation of uric acid in sodium hydroxide solution. The enzyme-less amperometric sensor used in the detection of uric acid with detection limit of 0.005 μM (S/N = 3) over wide linear detection ranges up to 0.374 mM and with a high sensitivity of 756.26 μA mM-1 cm-2, and a possible mechanism was also given in the paper.
Nie, Yan-Mei; Liang, Shuang; Yu, Wei-Dong; Yuan, Hao; Yan, Jun
2018-05-04
A pure inorganic 2D network molybdophosphate, [Mn 3 Mo 12 O 24 (OH) 6 (HPO 3 ) 8 (H 2 O) 6 ] 4- (1 a), synthesized through microwave irradiation with the existence of Mn 2+ and organic cations and isolated as [(CH 3 ) 2 NH 2 ] 3 Na[Mn 3 Mo 12 O 24 (OH) 6 (HPO 3 ) 8 (H 2 O) 6 ]⋅12 H 2 O (1), is found to possess highly enhanced performance in lithium-ion batteries' anode materials. The molecule shows multielectron redox properties suitable for producing anode materials with a specific capacity of 602 mA h g -1 at 100 mA g -1 after 50 cycles in lithium-ion batteries, although its specific capacity is the highest among all the reported pure inorganic 2D polyoxometalates to date, the cyclic stability is not that satisfactory. A hybrid nanocomposite of this 2D network and polypyrrole cations effectively reduces the capacity fading in initial cycles, and increases the stability and improves the electrochemical performance of lithium-ion batteries as well. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.
Liatis, S; Mylona, M; Kalopita, S; Papazafiropoulou, A; Karamagkiolis, S; Melidonis, A; Xilomenos, A; Ioannidis, I; Kaltsas, G; Lanaras, L; Papas, S; Basagiannis, C; Kokkinos, A
2015-04-01
Hypoglycaemia is considered a factor contributing to morbidity and mortality in patients with diabetes. The aim of the present study was to examine the frequency, clinical characteristics, predisposing factors and outcomes of iatrogenic hypoglycaemia requiring medical assistance. Eight hospitals participated in this prospective survey of documented iatrogenic hypoglycaemia at their emergency departments. Cases with type 2 diabetes (T2D) were compared with a control group, consisting of patients visiting the outpatients' diabetes clinics of the same hospitals during the same time period. Median survey duration was 16.5 months, and 295 episodes of iatrogenic hypoglycaemia were recorded. Frequency varied across centres from 0.25 to 0.78 cases per 100 presenting patients. Most cases (90.8%) were observed in patients with T2D (mean age: 76.7±10.1 years), while 8.1% of events were recorded in patients with type 1 diabetes (mean age: 42.7±18.3 years). Total in-hospital mortality was 3.4%, and all involved patients with T2D. In T2D patients, advanced age (OR: 1.3 [1.20-1.45] for 5-year increase), use of sulphonylureas (OR: 4.0 [2.5-6.36]), use of insulin (OR: 2.35 [1.42-3.95]), lower estimated GFR (OR: 1.15 [1.07-1.23] at 10mL/min) and number of comorbidities (OR: 1.74 [1.34-2.27]) were each independently associated with hypoglycaemia requiring medical assistance. Hypoglycaemia requiring medical assistance in patients with diabetes is a moderately common condition seen in emergency departments and has a mortality rate of 3.4%. The majority of cases involve elderly individuals with T2D who are suffering from serious comorbidities and treated with insulin and/or sulphonylureas. Copyright © 2014 Elsevier Masson SAS. All rights reserved.
Balbale, Salva N; Hill, Jennifer N; Guihan, Marylou; Hogan, Timothy P; Cameron, Kenzie A; Goldstein, Barry; Evans, Charlesnika T
2015-09-09
To prevent methicillin-resistant Staphylococcus aureus (MRSA) in Spinal Cord Injury and Disorder (SCI/D) Centers, the "Guidelines for Implementation of MRSA Prevention Initiative in the Spinal Cord Injury Centers" were released in July 2008 in the Veterans Affairs (VA) Health Care System. The purpose of this study was to use the Promoting Action on Research Implementation in Health Systems (PARiHS) framework to evaluate the experiences of implementation of SCI/D MRSA prevention guidelines in VA SCI/D Centers approximately 2-3 years after the guidelines were released. Mixed methods were used across two phases in this study. The first phase included an anonymous, web-based cross-sectional survey administered to providers at all 24 VA SCI/D Centers. The second phase included semi-structured telephone interviews with providers at 9 SCI/D Centers. The PARiHS framework was used as the foundation of both the survey questions and semi-structured interview guide. The survey was completed by 295 SCI/D providers (43.8 % response rate) from 22 of the 24 SCI/D Centers (91.7 % participation rate). Respondents included nurses (57.3 %), therapists (24.4 %), physicians (11.1 %), physician assistants (3.4 %), and other health care professionals (3.8 %). Approximately 36 % of the SCI/D providers surveyed had not seen, did not remember seeing, or had never heard of the MRSA SCI/D guidelines, whereas 42.3 % of providers reported that the MRSA SCI/D guidelines were fully implemented in their SCI/D Center. Data revealed numerous barriers and facilitators to guideline implementation. Facilitators included enhanced leadership support and provider education, focused guideline dissemination to reach SCI/D providers, and strong perceived evidence supporting the guidelines. Barriers included lack of awareness of the guidelines among physical therapists and physician assistants and challenges in cohorting/isolating MRSA-positive patients and following contact precautions. Successful implementation of MRSA infection prevention guidelines in SCI/D settings requires (1) guideline dissemination that reaches the full range of SCI/D providers working in inpatient, outpatient, and other care settings, (2) provider education that is frequent and systematic, (3) strong leadership support, and (4) that barriers unique to the recommendations are addressed. These findings may be used to inform selection of implementation strategies and optimize infection prevention beyond MRSA as well as in other specialty care populations.
Fisheye camera around view monitoring system
NASA Astrophysics Data System (ADS)
Feng, Cong; Ma, Xinjun; Li, Yuanyuan; Wu, Chenchen
2018-04-01
360 degree around view monitoring system is the key technology of the advanced driver assistance system, which is used to assist the driver to clear the blind area, and has high application value. In this paper, we study the transformation relationship between multi coordinate system to generate panoramic image in the unified car coordinate system. Firstly, the panoramic image is divided into four regions. By using the parameters obtained by calibration, four fisheye images pixel corresponding to the four sub regions are mapped to the constructed panoramic image. On the basis of 2D around view monitoring system, 3D version is realized by reconstructing the projection surface. Then, we compare 2D around view scheme and 3D around view scheme in unified coordinate system, 3D around view scheme solves the shortcomings of the traditional 2D scheme, such as small visual field, prominent ground object deformation and so on. Finally, the image collected by a fisheye camera installed around the car body can be spliced into a 360 degree panoramic image. So it has very high application value.
Harder, Stine; Paulsen, Rasmus R.; Larsen, Martin; Laugesen, Søren; Mihocic, Michael; Majdak, Piotr
2017-01-01
Individual head-related transfer functions (HRTFs) are essential in applications like fitting hearing-assistive devices (HADs) for providing accurate sound localization performance. Individual HRTFs are usually obtained through intricate acoustic measurements. This paper investigates the use of a three-dimensional (3D) head model for acquisition of individual HRTFs. Two aspects were investigated; whether a 3D-printed model can replace measurements on a human listener and whether numerical simulations can replace acoustic measurements. For this purpose, HRTFs were acoustically measured for four human listeners and for a 3D printed head model of one of these listeners. Further, HRTFs were simulated by applying the finite element method to the 3D head model. The monaural spectral features and spectral distortions were very similar between re-measurements and between human and printed measurements, however larger deviations were observed between measurement and simulation. The binaural cues were in agreement among all HRTFs of the same listener, indicating that the 3D model is able to provide localization cues potentially accessible to HAD users. Hence, the pipeline of geometry acquisition, printing, and acoustic measurements or simulations, seems to be a promising step forward towards in-silico design of HADs. PMID:28239188
Yap, Hong Kai; Sebastian, Frederick; Wiedeman, Christopher; Yeow, Chen-Hua
2017-07-01
We present the design of low-cost fabric-based Hat pneumatic actuators for soft assistive glove application. The soft assistive glove is designed to assist hand impaired patients in performing activities of daily living and rehabilitation. The actuators consist of flexible materials such as fabric and latex bladder. Using zero volume actuation concept, the 2D configuration of the actuators simplifies the manufacturing process and allows the actuators to be more compact. The actuators achieve bi-directional flexion and extension motions. Compared to previously developed inflatable soft actuators, the actuators generate sufficient force and torque to assist in both finger flexion and extension at lower air pressure. Preliminary evaluation results show that the glove is able to provide both active finger flexion and extension assistance for activities of daily living and rehabilitative training.
Navigation system for robot-assisted intra-articular lower-limb fracture surgery.
Dagnino, Giulio; Georgilas, Ioannis; Köhler, Paul; Morad, Samir; Atkins, Roger; Dogramadzi, Sanja
2016-10-01
In the surgical treatment for lower-leg intra-articular fractures, the fragments have to be positioned and aligned to reconstruct the fractured bone as precisely as possible, to allow the joint to function correctly again. Standard procedures use 2D radiographs to estimate the desired reduction position of bone fragments. However, optimal correction in a 3D space requires 3D imaging. This paper introduces a new navigation system that uses pre-operative planning based on 3D CT data and intra-operative 3D guidance to virtually reduce lower-limb intra-articular fractures. Physical reduction in the fractures is then performed by our robotic system based on the virtual reduction. 3D models of bone fragments are segmented from CT scan. Fragments are pre-operatively visualized on the screen and virtually manipulated by the surgeon through a dedicated GUI to achieve the virtual reduction in the fracture. Intra-operatively, the actual position of the bone fragments is provided by an optical tracker enabling real-time 3D guidance. The motion commands for the robot connected to the bone fragment are generated, and the fracture physically reduced based on the surgeon's virtual reduction. To test the system, four femur models were fractured to obtain four different distal femur fracture types. Each one of them was subsequently reduced 20 times by a surgeon using our system. The navigation system allowed an orthopaedic surgeon to virtually reduce the fracture with a maximum residual positioning error of [Formula: see text] (translational) and [Formula: see text] (rotational). Correspondent physical reductions resulted in an accuracy of 1.03 ± 0.2 mm and [Formula: see text], when the robot reduced the fracture. Experimental outcome demonstrates the accuracy and effectiveness of the proposed navigation system, presenting a fracture reduction accuracy of about 1 mm and [Formula: see text], and meeting the clinical requirements for distal femur fracture reduction procedures.
1982-12-01
Table A-3. Data on seasonal snowpack is not available for Revere. However, snow surveys by the Corps of Engineers in the Blackstone River basin, about 20...described previously, with less impact on the study area. Another consisted of the stabilization of existing facilities with a rock berm sloping 1 on 3... Tax Loss D-7 22. Acquisition Costs D-7 23. Relocations Assistance Costs D-7 24. Evaluation D-8 25. Summary of Real Estate Costs D-9 D-i V ..... F
Xu, Wei; Zhang, Xuming; Ke, Tie; Cai, Hongru; Gao, Xiang
2017-08-11
This study aimed to evaluate the application of 3D printing in assisting preoperative plan of pedicle screw placement for treating middle-upper thoracic trauma. A preoperative plan was implemented in seven patients suffering from middle-upper thoracic (T3-T7) trauma between March 2013 and February 2016. In the 3D printing models, entry points of 56 pedicle screws (Magerl method) and 4 important parameters of the pedicle screws were measured, including optimal diameter (ϕ, mm), length (L, mm), inclined angle (α), head-tilting angle (+β), and tail-tilting angle (-β). In the surgery, bare-hands fixation of pedicle screws was performed using 3D printing models and the measured parameters as guidance. A total of seven patients were enrolled, including five men and two women, with the age of 21-62 years (mean age of 37.7 years). The position of the pedicle screw was evaluated postoperatively using a computerized tomography scan. Totally, 56 pedicle screws were placed, including 33 pieces of level 0, 18 pieces of level 1, 4 pieces of level 2 (pierced lateral wall), and 1 piece of level 3 (pierced lateral wall, no adverse consequences), with a fine rate of 91.0%. 3D printing technique is an intuitive and effective assistive technology to pedicle screw fixation for treating middle-upper thoracic vertebrae, which improve the accuracy of bare-hands screw placement and reduce empirical errors. The trial was approved by the Ethics Committee of the Fujian Provincial Hospital. It was registered on March 1st, 2013, and the registration number was K2013-03-001.
Corona-Martínez, David Octavio; Gomez-Tagle, Paola; Yatsimirsky, Anatoly K
2012-10-19
Kinetics of transesterification of the RNA model substrate 2-hydroxypropyl 4-nitrophenyl phosphate promoted by Mg(2+) and Ca(2+), the most common biological metals acting as cofactors for nuclease enzymes and ribozymes, as well as by Co(NH(3))(6)(3+), Co(en)(3)(3+), Li(+), and Na(+) cations, often employed as mechanistic probes, was studied in 80% v/v (50 mol %) aqueous DMSO, a medium that allows one to discriminate easily specific base (OH(-)-catalyzed) and general base (buffer-catalyzed) reaction paths. All cations assist the specific base reaction, but only Mg(2+) and Na(+) assist the general base reaction. For Mg(2+)-assisted reactions, the solvent deuterium isotope effects are 1.23 and 0.25 for general base and specific base mechanisms, respectively. Rate constants for Mg(2+)-assisted general base reactions measured with different bases fit the Brønsted correlation with a slope of 0.38, significantly lower than the slope for the unassisted general base reaction (0.77). Transition state binding constants for catalysts in the specific base reaction (K(‡)(OH)) both in aqueous DMSO and pure water correlate with their binding constants to 4-nitrophenyl phosphate dianion (K(NPP)) used as a minimalist transition state model. It was found that K(‡)(OH) ≈ K(NPP) for "protic" catalysts (Co(NH(3))(6)(3+), Co(en)(3)(3+), guanidinium), but K(‡)(OH) ≫ K(NPP) for Mg(2+) and Ca(2+) acting as Lewis acids. It appears from results of this study that Mg(2+) is unique in its ability to assist efficiently the general base-catalyzed transesterification often occurring in active sites of nuclease enzymes and ribozymes.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Li, X.; Guo, F.; Wang, X.
One-dimensional (1D) nanotubes of Nd{sub 0.1}Bi{sub 0.9}FeO{sub 3} (NBFO) with an inner diameter of ∼50 nm were synthesized via sol-gel based electrospinning without template assistant. The phases, morphologies, crystalline structures, and magnetic properties of these 1D nanostructures were characterized by means of X-ray diffraction, scanning electron microscopy, transmission electron microscopy and SQUID, respectively. It was found that the calcination condition plays a crucial role in determining the morphologies and the magnetic properties. Interestingly, these 1D NBFO nanotubes exhibit wasp-waisted magnetic hysteresis with a lower coercivity and larger saturation magnetization, which were prevalent in natural rocks and artificial composite materials. The originmore » of these wasp-waisted hysteresis loops was discussed.« less
McMillan, Kathryn Anne; Kirk, Alison; Hewitt, Allan; MacRury, Sandra
2017-03-01
The aim was to review studies examining the effectiveness, acceptability, and feasibility of mobile-based technology for promoting active lifestyles in people with type 2 diabetes (T2D). Benefits of leading an active lifestyle following a diagnosis of T2D, including improved glycemic control, have been reported. Studies examining the specific use of mobile-based technologies to promote an active lifestyle in T2D have not previously been reviewed. Research studies examining effectiveness, feasibility or acceptability of mobile-based technology for active lifestyle promotion for T2D management were included (n = 9). The databases searched included PubMed, Medline, ScienceDirect, and ACM Digital Library (January 2005 to October 2015). Studies were categorized as (1) informing, (2) monitoring, (3) provoking, or (4) sustaining behavior change. Technologies used included smartphone or tablet apps, diabetes personal digital assistant, continuous glucose monitor and accelerometer, pedometer, and a website delivered by a smartphone. No articles examined the effectiveness of mobile-based technology in monitoring health behaviors and behavior change. Four of the studies found mobile-based technology to be motivational and supportive for behavior change. The visual reinforcement was identified as motivational. The feasibility and acceptability of using mobile-based technology to provide sustained lifestyle change and the effectiveness of mobile-based technology in monitoring health behaviors and behavior change have not been investigated. No studies examined all 3 of the outcomes or focused decreasing the participants' sedentary behavior. Limited research has examined the feasibility, acceptability, and effectiveness of mobile-based technology to promote active lifestyles and subsequently good diabetes management in people with T2D.
Emerging Applications of Bedside 3D Printing in Plastic Surgery
Chae, Michael P.; Rozen, Warren M.; McMenamin, Paul G.; Findlay, Michael W.; Spychal, Robert T.; Hunter-Smith, David J.
2015-01-01
Modern imaging techniques are an essential component of preoperative planning in plastic and reconstructive surgery. However, conventional modalities, including three-dimensional (3D) reconstructions, are limited by their representation on 2D workstations. 3D printing, also known as rapid prototyping or additive manufacturing, was once the province of industry to fabricate models from a computer-aided design (CAD) in a layer-by-layer manner. The early adopters in clinical practice have embraced the medical imaging-guided 3D-printed biomodels for their ability to provide tactile feedback and a superior appreciation of visuospatial relationship between anatomical structures. With increasing accessibility, investigators are able to convert standard imaging data into a CAD file using various 3D reconstruction softwares and ultimately fabricate 3D models using 3D printing techniques, such as stereolithography, multijet modeling, selective laser sintering, binder jet technique, and fused deposition modeling. However, many clinicians have questioned whether the cost-to-benefit ratio justifies its ongoing use. The cost and size of 3D printers have rapidly decreased over the past decade in parallel with the expiration of key 3D printing patents. Significant improvements in clinical imaging and user-friendly 3D software have permitted computer-aided 3D modeling of anatomical structures and implants without outsourcing in many cases. These developments offer immense potential for the application of 3D printing at the bedside for a variety of clinical applications. In this review, existing uses of 3D printing in plastic surgery practice spanning the spectrum from templates for facial transplantation surgery through to the formation of bespoke craniofacial implants to optimize post-operative esthetics are described. Furthermore, we discuss the potential of 3D printing to become an essential office-based tool in plastic surgery to assist in preoperative planning, developing intraoperative guidance tools, teaching patients and surgical trainees, and producing patient-specific prosthetics in everyday surgical practice. PMID:26137465
Emerging Applications of Bedside 3D Printing in Plastic Surgery.
Chae, Michael P; Rozen, Warren M; McMenamin, Paul G; Findlay, Michael W; Spychal, Robert T; Hunter-Smith, David J
2015-01-01
Modern imaging techniques are an essential component of preoperative planning in plastic and reconstructive surgery. However, conventional modalities, including three-dimensional (3D) reconstructions, are limited by their representation on 2D workstations. 3D printing, also known as rapid prototyping or additive manufacturing, was once the province of industry to fabricate models from a computer-aided design (CAD) in a layer-by-layer manner. The early adopters in clinical practice have embraced the medical imaging-guided 3D-printed biomodels for their ability to provide tactile feedback and a superior appreciation of visuospatial relationship between anatomical structures. With increasing accessibility, investigators are able to convert standard imaging data into a CAD file using various 3D reconstruction softwares and ultimately fabricate 3D models using 3D printing techniques, such as stereolithography, multijet modeling, selective laser sintering, binder jet technique, and fused deposition modeling. However, many clinicians have questioned whether the cost-to-benefit ratio justifies its ongoing use. The cost and size of 3D printers have rapidly decreased over the past decade in parallel with the expiration of key 3D printing patents. Significant improvements in clinical imaging and user-friendly 3D software have permitted computer-aided 3D modeling of anatomical structures and implants without outsourcing in many cases. These developments offer immense potential for the application of 3D printing at the bedside for a variety of clinical applications. In this review, existing uses of 3D printing in plastic surgery practice spanning the spectrum from templates for facial transplantation surgery through to the formation of bespoke craniofacial implants to optimize post-operative esthetics are described. Furthermore, we discuss the potential of 3D printing to become an essential office-based tool in plastic surgery to assist in preoperative planning, developing intraoperative guidance tools, teaching patients and surgical trainees, and producing patient-specific prosthetics in everyday surgical practice.
Kappanayil, Mahesh; Koneti, Nageshwara Rao; Kannan, Rajesh R; Kottayil, Brijesh P; Kumar, Krishna
2017-01-01
Three-dimensional. (3D) printing is an innovative manufacturing process that allows computer-assisted conversion of 3D imaging data into physical "printouts" Healthcare applications are currently in evolution. The objective of this study was to explore the feasibility and impact of using patient-specific 3D-printed cardiac prototypes derived from high-resolution medical imaging data (cardiac magnetic resonance imaging/computed tomography [MRI/CT]) on surgical decision-making and preoperative planning in selected cases of complex congenital heart diseases (CHDs). Five patients with complex CHD with previously unresolved management decisions were chosen. These included two patients with complex double-outlet right ventricle, two patients with criss-cross atrioventricular connections, and one patient with congenitally corrected transposition of great arteries with pulmonary atresia. Cardiac MRI was done for all patients, cardiac CT for one; specific surgical challenges were identified. Volumetric data were used to generate patient-specific 3D models. All cases were reviewed along with their 3D models, and the impact on surgical decision-making and preoperative planning was assessed. Accurate life-sized 3D cardiac prototypes were successfully created for all patients. The models enabled radically improved 3D understanding of anatomy, identification of specific technical challenges, and precise surgical planning. Augmentation of existing clinical and imaging data by 3D prototypes allowed successful execution of complex surgeries for all five patients, in accordance with the preoperative planning. 3D-printed cardiac prototypes can radically assist decision-making, planning, and safe execution of complex congenital heart surgery by improving understanding of 3D anatomy and allowing anticipation of technical challenges.
Integrated bronchoscopic video tracking and 3D CT registration for virtual bronchoscopy
NASA Astrophysics Data System (ADS)
Higgins, William E.; Helferty, James P.; Padfield, Dirk R.
2003-05-01
Lung cancer assessment involves an initial evaluation of 3D CT image data followed by interventional bronchoscopy. The physician, with only a mental image inferred from the 3D CT data, must guide the bronchoscope through the bronchial tree to sites of interest. Unfortunately, this procedure depends heavily on the physician's ability to mentally reconstruct the 3D position of the bronchoscope within the airways. In order to assist physicians in performing biopsies of interest, we have developed a method that integrates live bronchoscopic video tracking and 3D CT registration. The proposed method is integrated into a system we have been devising for virtual-bronchoscopic analysis and guidance for lung-cancer assessment. Previously, the system relied on a method that only used registration of the live bronchoscopic video to corresponding virtual endoluminal views derived from the 3D CT data. This procedure only performs the registration at manually selected sites; it does not draw upon the motion information inherent in the bronchoscopic video. Further, the registration procedure is slow. The proposed method has the following advantages: (1) it tracks the 3D motion of the bronchoscope using the bronchoscopic video; (2) it uses the tracked 3D trajectory of the bronchoscope to assist in locating sites in the 3D CT "virtual world" to perform the registration. In addition, the method incorporates techniques to: (1) detect and exclude corrupted video frames (to help make the video tracking more robust); (2) accelerate the computation of the many 3D virtual endoluminal renderings (thus, speeding up the registration process). We have tested the integrated tracking-registration method on a human airway-tree phantom and on real human data.
Qi, Jin; Yang, Zhiyong
2014-01-01
Real-time human activity recognition is essential for human-robot interactions for assisted healthy independent living. Most previous work in this area is performed on traditional two-dimensional (2D) videos and both global and local methods have been used. Since 2D videos are sensitive to changes of lighting condition, view angle, and scale, researchers begun to explore applications of 3D information in human activity understanding in recently years. Unfortunately, features that work well on 2D videos usually don't perform well on 3D videos and there is no consensus on what 3D features should be used. Here we propose a model of human activity recognition based on 3D movements of body joints. Our method has three steps, learning dictionaries of sparse codes of 3D movements of joints, sparse coding, and classification. In the first step, space-time volumes of 3D movements of body joints are obtained via dense sampling and independent component analysis is then performed to construct a dictionary of sparse codes for each activity. In the second step, the space-time volumes are projected to the dictionaries and a set of sparse histograms of the projection coefficients are constructed as feature representations of the activities. Finally, the sparse histograms are used as inputs to a support vector machine to recognize human activities. We tested this model on three databases of human activities and found that it outperforms the state-of-the-art algorithms. Thus, this model can be used for real-time human activity recognition in many applications.
Towards free 3D end-point control for robotic-assisted human reaching using binocular eye tracking.
Maimon-Dror, Roni O; Fernandez-Quesada, Jorge; Zito, Giuseppe A; Konnaris, Charalambos; Dziemian, Sabine; Faisal, A Aldo
2017-07-01
Eye-movements are the only directly observable behavioural signals that are highly correlated with actions at the task level, and proactive of body movements and thus reflect action intentions. Moreover, eye movements are preserved in many movement disorders leading to paralysis (or amputees) from stroke, spinal cord injury, Parkinson's disease, multiple sclerosis, and muscular dystrophy among others. Despite this benefit, eye tracking is not widely used as control interface for robotic interfaces in movement impaired patients due to poor human-robot interfaces. We demonstrate here how combining 3D gaze tracking using our GT3D binocular eye tracker with custom designed 3D head tracking system and calibration method enables continuous 3D end-point control of a robotic arm support system. The users can move their own hand to any location of the workspace by simple looking at the target and winking once. This purely eye tracking based system enables the end-user to retain free head movement and yet achieves high spatial end point accuracy in the order of 6 cm RMSE error in each dimension and standard deviation of 4 cm. 3D calibration is achieved by moving the robot along a 3 dimensional space filling Peano curve while the user is tracking it with their eyes. This results in a fully automated calibration procedure that yields several thousand calibration points versus standard approaches using a dozen points, resulting in beyond state-of-the-art 3D accuracy and precision.
Design and fabrication of a foldable 3D silicon based package for solid state lighting applications
NASA Astrophysics Data System (ADS)
Sokolovskij, R.; Liu, P.; van Zeijl, H. W.; Mimoun, B.; Zhang, G. Q.
2015-05-01
Miniaturization of solid state lighting (SSL) luminaires as well as reduction of packaging and assembly costs are of prime interest for the SSL lighting industry. A novel silicon based LED package for lighting applications is presented in this paper. The proposed design consists of 5 rigid Si tiles connected by flexible polyimide hinges with embedded interconnects (ICs). Electrical, optical and thermal characteristics were taken into consideration during design. The fabrication process involved polyimide (PI) application and patterning, aluminium interconnect integration in the flexible hinge, LED reflector cavity formation and metalization followed by through wafer DRIE etching for chip formation and release. A method to connect chip front to backside without TSVs was also integrated into the process. Post-fabrication wafer level assembly included LED mounting and wirebond, phosphor-based colour conversion and silicone encapsulation. The package formation was finalized by vacuum assisted wrapping around an assembly structure to form a 3D geometry, which is beneficial for omnidirectional lighting. Bending tests were performed on the flexible ICs and optical performance at different temperatures was evaluated. It is suggested that 3D packages can be expanded to platforms for miniaturized luminaire applications by combining monolithic silicon integration and system-in-package (SiP) technologies.
Preliminary results in large bone segmentation from 3D freehand ultrasound
NASA Astrophysics Data System (ADS)
Fanti, Zian; Torres, Fabian; Arámbula Cosío, Fernando
2013-11-01
Computer Assisted Orthopedic Surgery (CAOS) requires a correct registration between the patient in the operating room and the virtual models representing the patient in the computer. In order to increase the precision and accuracy of the registration a set of new techniques that eliminated the need to use fiducial markers have been developed. The majority of these newly developed registration systems are based on costly intraoperative imaging systems like Computed Tomography (CT scan) or Magnetic resonance imaging (MRI). An alternative to these methods is the use of an Ultrasound (US) imaging system for the implementation of a more cost efficient intraoperative registration solution. In order to develop the registration solution with the US imaging system, the bone surface is segmented in both preoperative and intraoperative images, and the registration is done using the acquire surface. In this paper, we present the a preliminary results of a new approach to segment bone surface from ultrasound volumes acquired by means 3D freehand ultrasound. The method is based on the enhancement of the voxels that belongs to surface and its posterior segmentation. The enhancement process is based on the information provided by eigenanalisis of the multiscale 3D Hessian matrix. The preliminary results shows that from the enhance volume the final bone surfaces can be extracted using a singular value thresholding.
Medical three-dimensional printing opens up new opportunities in cardiology and cardiac surgery.
Bartel, Thomas; Rivard, Andrew; Jimenez, Alejandro; Mestres, Carlos A; Müller, Silvana
2018-04-14
Advanced percutaneous and surgical procedures in structural and congenital heart disease require precise pre-procedural planning and continuous quality control. Although current imaging modalities and post-processing software assists with peri-procedural guidance, their capabilities for spatial conceptualization remain limited in two- and three-dimensional representations. In contrast, 3D printing offers not only improved visualization for procedural planning, but provides substantial information on the accuracy of surgical reconstruction and device implantations. Peri-procedural 3D printing has the potential to set standards of quality assurance and individualized healthcare in cardiovascular medicine and surgery. Nowadays, a variety of clinical applications are available showing how accurate 3D computer reformatting and physical 3D printouts of native anatomy, embedded pathology, and implants are and how they may assist in the development of innovative therapies. Accurate imaging of pathology including target region for intervention, its anatomic features and spatial relation to the surrounding structures is critical for selecting optimal approach and evaluation of procedural results. This review describes clinical applications of 3D printing, outlines current limitations, and highlights future implications for quality control, advanced medical education and training.
Zhan, Hualin; Garrett, David J.; Apollo, Nicholas V.; Ganesan, Kumaravelu; Lau, Desmond; Prawer, Steven; Cervenka, Jiri
2016-01-01
High surface area electrode materials are of interest for a wide range of potential applications such as super-capacitors and electrochemical cells. This paper describes a fabrication method of three-dimensional (3D) graphene conformally coated on nanoporous insulating substrate with uniform nanopore size. 3D graphene films were formed by controlled graphitization of diamond-like amorphous carbon precursor films, deposited by plasma-enhanced chemical vapour deposition (PECVD). Plasma-assisted graphitization was found to produce better quality graphene than a simple thermal graphitization process. The resulting 3D graphene/amorphous carbon/alumina structure has a very high surface area, good electrical conductivity and exhibits excellent chemically stability, providing a good material platform for electrochemical applications. Consequently very large electrochemical capacitance values, as high as 2.1 mF for a sample of 10 mm3, were achieved. The electrochemical capacitance of the material exhibits a dependence on bias voltage, a phenomenon observed by other groups when studying graphene quantum capacitance. The plasma-assisted graphitization, which dominates the graphitization process, is analyzed and discussed in detail. PMID:26805546
Zhan, Hualin; Garrett, David J; Apollo, Nicholas V; Ganesan, Kumaravelu; Lau, Desmond; Prawer, Steven; Cervenka, Jiri
2016-01-25
High surface area electrode materials are of interest for a wide range of potential applications such as super-capacitors and electrochemical cells. This paper describes a fabrication method of three-dimensional (3D) graphene conformally coated on nanoporous insulating substrate with uniform nanopore size. 3D graphene films were formed by controlled graphitization of diamond-like amorphous carbon precursor films, deposited by plasma-enhanced chemical vapour deposition (PECVD). Plasma-assisted graphitization was found to produce better quality graphene than a simple thermal graphitization process. The resulting 3D graphene/amorphous carbon/alumina structure has a very high surface area, good electrical conductivity and exhibits excellent chemically stability, providing a good material platform for electrochemical applications. Consequently very large electrochemical capacitance values, as high as 2.1 mF for a sample of 10 mm(3), were achieved. The electrochemical capacitance of the material exhibits a dependence on bias voltage, a phenomenon observed by other groups when studying graphene quantum capacitance. The plasma-assisted graphitization, which dominates the graphitization process, is analyzed and discussed in detail.
Code of Federal Regulations, 2010 CFR
2010-10-01
... DEFENSE SOCIOECONOMIC PROGRAMS OTHER SOCIOECONOMIC PROGRAMS Historically Black Colleges and Universities and Minority Institutions 226.370-3 Policy. DoD will use outreach efforts, technical assistance...
Tsai, Tsung-Yuan; Li, Jing-Sheng; Wang, Shaobai; Li, Pingyue; Kwon, Young-Min; Li, Guoan
2015-01-01
The statistical shape model (SSM) method that uses 2D images of the knee joint to predict the three-dimensional (3D) joint surface model has been reported in the literature. In this study, we constructed a SSM database using 152 human computed tomography (CT) knee joint models, including the femur, tibia and patella and analysed the characteristics of each principal component of the SSM. The surface models of two in vivo knees were predicted using the SSM and their 2D bi-plane fluoroscopic images. The predicted models were compared to their CT joint models. The differences between the predicted 3D knee joint surfaces and the CT image-based surfaces were 0.30 ± 0.81 mm, 0.34 ± 0.79 mm and 0.36 ± 0.59 mm for the femur, tibia and patella, respectively (average ± standard deviation). The computational time for each bone of the knee joint was within 30 s using a personal computer. The analysis of this study indicated that the SSM method could be a useful tool to construct 3D surface models of the knee with sub-millimeter accuracy in real time. Thus, it may have a broad application in computer-assisted knee surgeries that require 3D surface models of the knee.
44 CFR 321.3 - Maintaining the mobilization base.
Code of Federal Regulations, 2010 CFR
2010-10-01
... 44 Emergency Management and Assistance 1 2010-10-01 2010-10-01 false Maintaining the mobilization base. 321.3 Section 321.3 Emergency Management and Assistance FEDERAL EMERGENCY MANAGEMENT AGENCY, DEPARTMENT OF HOMELAND SECURITY PREPAREDNESS MAINTENANCE OF THE MOBILIZATION BASE (DEPARTMENT OF DEFENSE...
Scano, A; Chiavenna, A; Caimmi, M; Malosio, M; Tosatti, L M; Molteni, F
2017-07-01
Robot-assisted training is a widely used technique to promote motor re-learning on post-stroke patients that suffer from motor impairment. While it is commonly accepted that robot-based therapies are potentially helpful, strong insights about their efficacy are still lacking. The motor re-learning process may act on muscular synergies, which are groups of co-activating muscles that, being controlled as a synergic group, allow simplifying the problem of motor control. In fact, by coordinating a reduced amount of neural signals, complex motor patterns can be elicited. This paper aims at analyzing the effects of robot assistance during 3D-reaching movements in the framework of muscular synergies. 5 healthy people and 3 neurological patients performed free and robot-assisted reaching movements at 2 different speeds (slow and quasi-physiological). EMG recordings were used to extract muscular synergies. Results indicate that the interaction with the robot very slightly alters healthy people patterns but, on the contrary, it may promote the emergency of physiological-like synergies on neurological patients.
Zeng, Yang; Feng, Siyu; Liu, Wei; Fu, Qinyouen; Li, Yaqian; Li, Xiaokang; Chen, Chun; Huang, Chenyu; Ge, Zigang; Du, Yanan
2017-04-01
To precondition mesenchymal stromal/stem cells (MSCs) with mechanical stimulation may enhance cell survival and functions following implantation in load bearing environment such as nucleus pulposus (NP) in intervertebral disc (IVD). In this study, preconditioning of MSCs toward NP-like cells was achieved in previously developed poly (ethylene glycol) diacrylate (PEGDA) microcryogels (PMs) within a syringe-based three-dimensional (3D) culture system which provided a facile and cost-effective pressure loading approach. PMs loaded with alginate and MSCs could be incubated in a sealable syringe which could be air-compressed to apply pressure loading through a programmable syringe pump. Expression levels of chondrogenic marker genes SOX9, COL II, and ACAN were significantly upregulated in MSCs when pressure loading of 0.2 MPa or 0.8 MPa was implemented. Expression levels of COL I and COL X were downregulated when pressure loading was applied. In a nude mouse model, MSCs loaded in PMs mechanically stimulated for three days were subcutaneously injected using the same culture syringe. Three weeks postinjection, more proteoglycans (PGs) were deposited and more SOX9 and COL II but less COL I and COL X were stained in 0.2 MPa group. Furthermore, injectable MSCs-loaded PMs were utilized in an ex vivo rabbit IVD organ culture model that demonstrated the leak-proof function and enhanced cell retention of PMs assisted cell delivery to a load bearing environment for potential NP regeneration. This microcryogels-based 3D cell culture and syringe-based pressure loading system represents a novel method for 3D cell culture with mechanical stimulation for better function. © 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 507-520, 2017. © 2015 Wiley Periodicals, Inc.
Balaya, V; Uhl, J-F; Lanore, A; Salachas, C; Samoyeau, T; Ngo, C; Bensaid, C; Cornou, C; Rossi, L; Douard, R; Bats, A-S; Lecuru, F; Delmas, V
2016-05-01
To achieve a 3D vectorial model of a female pelvis by Computer-Assisted Anatomical Dissection and to assess educationnal and surgical applications. From the database of "visible female" of Visible Human Project(®) (VHP) of the "national library of medicine" NLM (United States), we used 739 transverse anatomical slices of 0.33mm thickness going from L4 to the trochanters. The manual segmentation of each anatomical structures was done with Winsurf(®) software version 4.3. Each anatomical element was built as a separate vectorial object. The whole colored-rendered vectorial model with realistic textures was exported in 3Dpdf format to allow a real time interactive manipulation with Acrobat(®) pro version 11 software. Each element can be handled separately at any transparency, which allows an anatomical learning by systems: skeleton, pelvic organs, urogenital system, arterial and venous vascularization. This 3D anatomical model can be used as data bank to teach of the fundamental anatomy. This 3D vectorial model, realistic and interactive constitutes an efficient educational tool for the teaching of the anatomy of the pelvis. 3D printing of the pelvis is possible with the new printers. Copyright © 2016 Elsevier Masson SAS. All rights reserved.
A New Methodology for 3D Target Detection in Automotive Radar Applications
Baselice, Fabio; Ferraioli, Giampaolo; Lukin, Sergyi; Matuozzo, Gianfranco; Pascazio, Vito; Schirinzi, Gilda
2016-01-01
Today there is a growing interest in automotive sensor monitoring systems. One of the main challenges is to make them an effective and valuable aid in dangerous situations, improving transportation safety. The main limitation of visual aid systems is that they do not produce accurate results in critical visibility conditions, such as in presence of rain, fog or smoke. Radar systems can greatly help in overcoming such limitations. In particular, imaging radar is gaining interest in the framework of Driver Assistance Systems (DAS). In this manuscript, a new methodology able to reconstruct the 3D imaged scene and to detect the presence of multiple targets within each line of sight is proposed. The technique is based on the use of Compressive Sensing (CS) theory and produces the estimation of multiple targets for each line of sight, their range distance and their reflectivities. Moreover, a fast approach for 2D focus based on the FFT algorithm is proposed. After the description of the proposed methodology, different simulated case studies are reported in order to evaluate the performances of the proposed approach. PMID:27136558
Plasma jet printing of electronic materials on flexible and nonconformal objects.
Gandhiraman, Ram P; Jayan, Vivek; Han, Jin-Woo; Chen, Bin; Koehne, Jessica E; Meyyappan, M
2014-12-10
We present a novel approach for the room-temperature fabrication of conductive traces and their subsequent site-selective dielectric encapsulation for use in flexible electronics. We have developed an aerosol-assisted atmospheric pressure plasma-based deposition process for efficiently depositing materials on flexible substrates. Silver nanowire conductive traces and silicon dioxide dielectric coatings for encapsulation were deposited using this approach as a demonstration. The paper substrate with silver nanowires exhibited a very low change in resistance upon 50 cycles of systematic deformation, exhibiting high mechanical flexibility. The applicability of this process to print conductive traces on nonconformal 3D objects was also demonstrated through deposition on a 3D-printed thermoplastic object, indicating the potential to combine plasma printing with 3D printing technology. The role of plasma here includes activation of the material present in the aerosol for deposition, increasing the deposition rate, and plasma polymerization in the case of inorganic coatings. The demonstration here establishes a low-cost, high-throughput, and facile process for printing electronic components on nonconventional platforms.
Classification of kidney and liver tissue using ultrasound backscatter data
NASA Astrophysics Data System (ADS)
Aalamifar, Fereshteh; Rivaz, Hassan; Cerrolaza, Juan J.; Jago, James; Safdar, Nabile; Boctor, Emad M.; Linguraru, Marius G.
2015-03-01
Ultrasound (US) tissue characterization provides valuable information for the initialization of automatic segmentation algorithms, and can further provide complementary information for diagnosis of pathologies. US tissue characterization is challenging due to the presence of various types of image artifacts and dependence on the sonographer's skills. One way of overcoming this challenge is by characterizing images based on the distribution of the backscatter data derived from the interaction between US waves and tissue. The goal of this work is to classify liver versus kidney tissue in 3D volumetric US data using the distribution of backscatter US data recovered from end-user displayed Bmode image available in clinical systems. To this end, we first propose the computation of a large set of features based on the homodyned-K distribution of the speckle as well as the correlation coefficients between small patches in 3D images. We then utilize the random forests framework to select the most important features for classification. Experiments on in-vivo 3D US data from nine pediatric patients with hydronephrosis showed an average accuracy of 94% for the classification of liver and kidney tissues showing a good potential of this work to assist in the classification and segmentation of abdominal soft tissue.
NASA Astrophysics Data System (ADS)
Shahedi, Maysam; Fenster, Aaron; Cool, Derek W.; Romagnoli, Cesare; Ward, Aaron D.
2013-03-01
3D segmentation of the prostate in medical images is useful to prostate cancer diagnosis and therapy guidance, but is time-consuming to perform manually. Clinical translation of computer-assisted segmentation algorithms for this purpose requires a comprehensive and complementary set of evaluation metrics that are informative to the clinical end user. We have developed an interactive 3D prostate segmentation method for 1.5T and 3.0T T2-weighted magnetic resonance imaging (T2W MRI) acquired using an endorectal coil. We evaluated our method against manual segmentations of 36 3D images using complementary boundary-based (mean absolute distance; MAD), regional overlap (Dice similarity coefficient; DSC) and volume difference (ΔV) metrics. Our technique is based on inter-subject prostate shape and local boundary appearance similarity. In the training phase, we calculated a point distribution model (PDM) and a set of local mean intensity patches centered on the prostate border to capture shape and appearance variability. To segment an unseen image, we defined a set of rays - one corresponding to each of the mean intensity patches computed in training - emanating from the prostate centre. We used a radial-based search strategy and translated each mean intensity patch along its corresponding ray, selecting as a candidate the boundary point with the highest normalized cross correlation along each ray. These boundary points were then regularized using the PDM. For the whole gland, we measured a mean+/-std MAD of 2.5+/-0.7 mm, DSC of 80+/-4%, and ΔV of 1.1+/-8.8 cc. We also provided an anatomic breakdown of these metrics within the prostatic base, mid-gland, and apex.
76 FR 18231 - Federal Property Suitable as Facilities To Assist the Homeless
Federal Register 2010, 2011, 2012, 2013, 2014
2011-04-01
...-101 and 15-115 Olympic Nat'l Park Lake Crescent WA 98362 Landholding Agency: Interior Property Number... National Coalition for the Homeless v. Veterans Administration, No. 88-2503-OG (D.D.C.). Properties...-based paint [[Page 18232
Li, Guoqiang; Li, Jiawen; Zhang, Chenchu; Hu, Yanlei; Li, Xiaohong; Chu, Jiaru; Huang, Wenhao; Wu, Dong
2015-01-14
The capability to realize 2D-3D controllable metallic micro/nanostructures is of key importance for various fields such as plasmonics, electronics, bioscience, and chemistry due to unique properties such as electromagnetic field enhancement, catalysis, photoemission, and conductivity. However, most of the present techniques are limited to low-dimension (1D-2D), small area, or single function. Here we report the assembly of self-organized three-dimensional (3D) porous metal micro/nanocages arrays on nickel surface by ethanol-assisted femtosecond laser irradiation. The underlying formation mechanism was investigated by a series of femtosecond laser irradiation under exposure time from 5 to 30 ms. We also demonstrate the ability to control the size of micro/nanocage arrays from 0.8 to 2 μm by different laser pulse energy. This method features rapidness (∼10 min), simplicity (one-step process), and ease of large-area (4 cm(2) or more) fabrication. The 3D cagelike micro/nanostructures exhibit not only improved antireflection from 80% to 7% but also enhanced hydrophobicity from 98.5° to 142° without surface modification. This simple technique for 3D large-area controllable metal microstructures will find great potential applications in optoelectronics, physics, and chemistry.
NASA Astrophysics Data System (ADS)
Irwansyah; Sinh, N. P.; Lai, J. Y.; Essomba, T.; Asbar, R.; Lee, P. Y.
2018-02-01
In this paper, we present study to integrate virtual fracture bone reduction simulation tool with a novel hybrid 3-DOF-RPS external fixator to relocate back bone fragments into their anatomically original position. A 3D model of fractured bone was reconstructed and manipulated using 3D design and modeling software, PhysiGuide. The virtual reduction system was applied to reduce a bilateral femoral shaft fracture type 32-A3. Measurement data from fracture reduction and fixation stages were implemented to manipulate the manipulator pose in patient’s clinical case. The experimental result presents that by merging both of those techniques will give more possibilities to reduce virtual bone reduction time, improve facial and shortest healing treatment.
NASA Astrophysics Data System (ADS)
Zheng, Guoyan
2007-03-01
Surgical navigation systems visualize the positions and orientations of surgical instruments and implants as graphical overlays onto a medical image of the operated anatomy on a computer monitor. The orthopaedic surgical navigation systems could be categorized according to the image modalities that are used for the visualization of surgical action. In the so-called CT-based systems or 'surgeon-defined anatomy' based systems, where a 3D volume or surface representation of the operated anatomy could be constructed from the preoperatively acquired tomographic data or through intraoperatively digitized anatomy landmarks, a photorealistic rendering of the surgical action has been identified to greatly improve usability of these navigation systems. However, this may not hold true when the virtual representation of surgical instruments and implants is superimposed onto 2D projection images in a fluoroscopy-based navigation system due to the so-called image occlusion problem. Image occlusion occurs when the field of view of the fluoroscopic image is occupied by the virtual representation of surgical implants or instruments. In these situations, the surgeon may miss part of the image details, even if transparency and/or wire-frame rendering is used. In this paper, we propose to use non-photorealistic rendering to overcome this difficulty. Laboratory testing results on foamed plastic bones during various computer-assisted fluoroscopybased surgical procedures including total hip arthroplasty and long bone fracture reduction and osteosynthesis are shown.
Lü, Xing-Qiang; Jiang, Ji-Jun; Chen, Chun-Long; Kang, Bei-Sheng; Su, Cheng-Yong
2005-06-27
The reactions of Cu(II) with the mixed nitrilotriacetic acid (H3NTA) and 4,4'-bipyridyl (4,4'-bpy) ligands in different metal-to-ligand ratios in the presence of NaOH and NaClO4 afforded two complexes, Na3[Cu2(NTA)2(4,4'-bpy)]ClO4 x 5H2O (1) and [Cu2(NTA) (4,4'-bpy)2]ClO4 x 4H2O (2). The two complexes have been characterized by elemental analysis, IR, XRD, and single-crystal X-ray diffraction. 1 contains a basic doubly negatively charged [Cu2(NTA)2(4,4'-bpy)]2- dinuclear unit which was further assembled via multiple Na-O and O-H...O interactions into a three-dimensional (3D) pillared-layer structure. 2 features a two-dimensional (2D) undulated brick-wall architecture containing a basic doubly positively charged [Cu4(NTA)2(4,4'-bpy)2]2+ tetranuclear unit. The 2D network possesses large cavities hosting guest molecules and was further assembled via O-H...O hydrogen bonds into a 3D structure with several channels running in different directions.
3D automatic anatomy recognition based on iterative graph-cut-ASM
NASA Astrophysics Data System (ADS)
Chen, Xinjian; Udupa, Jayaram K.; Bagci, Ulas; Alavi, Abass; Torigian, Drew A.
2010-02-01
We call the computerized assistive process of recognizing, delineating, and quantifying organs and tissue regions in medical imaging, occurring automatically during clinical image interpretation, automatic anatomy recognition (AAR). The AAR system we are developing includes five main parts: model building, object recognition, object delineation, pathology detection, and organ system quantification. In this paper, we focus on the delineation part. For the modeling part, we employ the active shape model (ASM) strategy. For recognition and delineation, we integrate several hybrid strategies of combining purely image based methods with ASM. In this paper, an iterative Graph-Cut ASM (IGCASM) method is proposed for object delineation. An algorithm called GC-ASM was presented at this symposium last year for object delineation in 2D images which attempted to combine synergistically ASM and GC. Here, we extend this method to 3D medical image delineation. The IGCASM method effectively combines the rich statistical shape information embodied in ASM with the globally optimal delineation capability of the GC method. We propose a new GC cost function, which effectively integrates the specific image information with the ASM shape model information. The proposed methods are tested on a clinical abdominal CT data set. The preliminary results show that: (a) it is feasible to explicitly bring prior 3D statistical shape information into the GC framework; (b) the 3D IGCASM delineation method improves on ASM and GC and can provide practical operational time on clinical images.
Paranasal sinuses and nasopharynx CT and MRI.
Sievers, K W; Greess, H; Baum, U; Dobritz, M; Lenz, M
2000-03-01
Neoplastic disease of the nose, paranasal sinuses, the nasopharynx and the parapharyngeal space requires thorough assessment of location and extent in order to plan appropriate treatment. CT allows the deep soft tissue planes to be evaluated and provides a complement to the physical examination. It is especially helpful in regions involving thin bony structures (paranasal sinuses, orbita); here CT performs better than MRI. MRI possesses many advantages over other imaging modalities caused by its excellent tissue contrast. In evaluating regions involving predominantly soft tissue structures (ec nasopharynx and parapharyngeal space) MRI is superior to CT. The possibility to obtain strictly consecutive volume data sets with spiral CT or 3D MRI offer excellent perspectives to visualize the data via 2D or 3D postprocessing. Because head and neck tumors reside in a complex area, having a 3D model of the anatomical features may assist in the delineation of pathology. Data sets may be transferred directly into computer systems and thus be used in computer assisted surgery.
NASA Astrophysics Data System (ADS)
Choi, Jae Hyung; Kuk, Jung Gap; Kim, Young Il; Cho, Nam Ik
2012-01-01
This paper proposes an algorithm for the detection of pillars or posts in the video captured by a single camera implemented on the fore side of a room mirror in a car. The main purpose of this algorithm is to complement the weakness of current ultrasonic parking assist system, which does not well find the exact position of pillars or does not recognize narrow posts. The proposed algorithm is consisted of three steps: straight line detection, line tracking, and the estimation of 3D position of pillars. In the first step, the strong lines are found by the Hough transform. Second step is the combination of detection and tracking, and the third is the calculation of 3D position of the line by the analysis of trajectory of relative positions and the parameters of camera. Experiments on synthetic and real images show that the proposed method successfully locates and tracks the position of pillars, which helps the ultrasonic system to correctly locate the edges of pillars. It is believed that the proposed algorithm can also be employed as a basic element for vision based autonomous driving system.
3D-Monitoring Big Geo Data on a seaport infrastructure based on FIWARE
NASA Astrophysics Data System (ADS)
Fernández, Pablo; Suárez, José Pablo; Trujillo, Agustín; Domínguez, Conrado; Santana, José Miguel
2018-04-01
Many organizations of all kinds are using new technologies to assist the acquisition and analysis of data. Seaports are a good example of this trend. Seaports generate data regarding the management of marine traffic and other elements, as well as environmental conditions given by meteorological sensors and buoys. However, this enormous amount of data, also known as Big Data, is useless without a proper system to organize, analyze and visualize it. SmartPort is an online platform for the visualization and management of a seaport data that has been built as a GIS application. This work offers a Rich Internet Application that allows the user to visualize and manage the different sources of information produced in a port environment. The Big Data management is based on the FIWARE platform, as well as "The Internet of Things" solutions for the data acquisition. At the same time, Glob3 Mobile (G3M) framework has been used for the development of map requirements. In this way, SmartPort supports 3D visualization of the ports scenery and its data sources.
3D-Monitoring Big Geo Data on a seaport infrastructure based on FIWARE
NASA Astrophysics Data System (ADS)
Fernández, Pablo; Suárez, José Pablo; Trujillo, Agustín; Domínguez, Conrado; Santana, José Miguel
2018-03-01
Many organizations of all kinds are using new technologies to assist the acquisition and analysis of data. Seaports are a good example of this trend. Seaports generate data regarding the management of marine traffic and other elements, as well as environmental conditions given by meteorological sensors and buoys. However, this enormous amount of data, also known as Big Data, is useless without a proper system to organize, analyze and visualize it. SmartPort is an online platform for the visualization and management of a seaport data that has been built as a GIS application. This work offers a Rich Internet Application that allows the user to visualize and manage the different sources of information produced in a port environment. The Big Data management is based on the FIWARE platform, as well as "The Internet of Things" solutions for the data acquisition. At the same time, Glob3 Mobile (G3M) framework has been used for the development of map requirements. In this way, SmartPort supports 3D visualization of the ports scenery and its data sources.
Three-dimensional printing in congenital heart disease: A systematic review.
Lau, Ivan; Sun, Zhonghua
2018-02-17
Three-dimensional (3D) printing has shown great promise in medicine with increasing reports in congenital heart disease (CHD). This systematic review aims to analyse the main clinical applications and accuracy of 3D printing in CHD, as well as to provide an overview of the software tools, time and costs associated with the generation of 3D printed heart models. A search of different databases was conducted to identify studies investigating the application of 3D printing in CHD. Studies based on patient's medical imaging datasets were included for analysis, while reports on in vitro phantom or review articles were excluded from the analysis. A total of 28 studies met selection criteria for inclusion in the review. More than half of the studies were based on isolated case reports with inclusion of 1-12 cases (61%), while 10 studies (36%) focused on the survey of opinion on the usefulness of 3D printing by healthcare professionals, patients, parents of patients and medical students, and the remaining one involved a multicentre study about the clinical value of 3D printed models in surgical planning of CHD. The analysis shows that patient-specific 3D printed models accurately replicate complex cardiac anatomy, improve understanding and knowledge about congenital heart diseases and demonstrate value in preoperative planning and simulation of cardiac or interventional procedures, assist surgical decision-making and intra-operative orientation, and improve patient-doctor communication and medical education. The cost of 3D printing ranges from USD 55 to USD 810. This systematic review shows the usefulness of 3D printed models in congenital heart disease with applications ranging from accurate replication of complex cardiac anatomy and pathology to medical education, preoperative planning and simulation. The additional cost and time required to manufacture the 3D printed models represent the limitations which need to be addressed in future studies. © 2018 The Authors. Journal of Medical Radiation Sciences published by John Wiley & Sons Australia, Ltd on behalf of Australian Society of Medical Imaging and Radiation Therapy and New Zealand Institute of Medical Radiation Technology.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lei, Xiao-Ping; Lian, Ting-Ting; Chen, Shu-Mei, E-mail: csm@fzu.edu.cn
Seven new metal-1,3,5-benzenetricarboxylate coordination polymers have been synthesized by modification of auxiliary components during the assembly reactions. Their structures have been determined by single-crystal X-ray diffraction analyses and further characterized by XRD and TGA. Interestingly, they show fascinating topological structures. Compounds 1 and 2 possess the undulating layer structure with 3-connected hcb network and (3,6)-connected kgd network. Compound 3 possesses three-dimensional (3D) pillared-layer structure with 3-connected 2-fold interpenetrating srs net. Compound 4 also has the 3D 2-fold interpenetrating pillared-layer structure; however, it has (3,5)-connected hms topology because the Cd(II) center is 5-connected. Compound 5 possess 3D structure through hydrogen bondingmore » interactions between ladder-like layers. Compounds 6 and 7 have the similar 3D frameworks with 4-connected umc net and (3,7)-connected (3.4.5)(3{sup 2}.4{sup 6}.5{sup 5}.6{sup 8}) topology, respectively. The photoluminescent properties of compounds 2–7 were also investigated. - Graphical abstract: Presented here are seven new metal-1,3,5-benzenetricarboxylate coordination polymers with diverse structures from 2D layers to 3D open frameworks. The synthesis and structural diversity of these compounds are determined by the additional amino acids as unusual buffering agents. - Highlights: • Structural diversity of metal-1,3,5-benzenetricarboxylate frameworks. • Tuning structural topologies of MOFs via the assistance of amino acids. • Amino acids as unusual buffering agents for the synthesis of MOFs.« less
3-D loaded scaffolds obtained by supercritical CO2 assisted process
NASA Astrophysics Data System (ADS)
Cardea, S.; Reverchon, E.
2014-08-01
In this work, a supercritical CO2 (SC-CO2) drying process for the formation of 3-D PVDF-HFP loaded scaffolds was tested. Experiments at pressures ranging between 150 and 250 bar and at temperatures ranging between 35 and 55°C were performed. The PVDF-HFP- acetone-ethanol solution at 15% w/w polymer was selected as the base case. The drug (amoxicillin) concentration was varied from 20 to 30% w/w with respect to PVDF-HFP. SC- CO2 drying process was confirmed to be a valid alternative to generate loaded structures; indeed, scaffolds characterized by nanometric networks (with mean pore diameter of about 300 nm) with a homogeneous drug distribution were obtained. Drug controlled release experiments were also performed and a quasi-zero order release kinetic was observed.
NASA Astrophysics Data System (ADS)
Homainejad, Amir S.; Satari, Mehran
2000-05-01
VR is possible which brings users to the reality by computer and VE is a simulated world which takes users to any points and directions of the object. VR and VE can be very useful if accurate and precise data are sued, and allows users to work with realistic model. Photogrammetry is a technique which is able to collect and provide accurate and precise data for building 3D model in a computer. Data can be collected from various sensor and cameras, and methods of data collector are vary based on the method of image acquiring. Indeed VR includes real-time graphics, 3D model, and display and it has application in the entertainment industry, flight simulators, industrial design.
Ding, Xueqin; Li, Li; Wang, Yuzhi; Chen, Jing; Huang, Yanhua; Xu, Kaijia
2014-12-01
A series of novel tetramethylguanidinium ionic liquids and hexaalkylguanidinium ionic liquids have been synthesized based on 1,1,3,3-tetramethylguanidine. The structures of the ionic liquids were confirmed by (1)H NMR spectroscopy and mass spectrometry. A green guanidinium ionic liquid based microwave-assisted extraction method has been developed with these guanidinium ionic liquids for the effective extraction of Praeruptorin A from Radix peucedani. After extraction, reversed-phase high-performance liquid chromatography with UV detection was employed for the analysis of Praeruptorin A. Several significant operating parameters were systematically optimized by single-factor and L9 (3(4)) orthogonal array experiments. The amount of Praeruptorin A extracted by [1,1,3,3-tetramethylguanidine]CH2CH(OH)COOH is the highest, reaching 11.05 ± 0.13 mg/g. Guanidinium ionic liquid based microwave-assisted extraction presents unique advantages in Praeruptorin A extraction compared with guanidinium ionic liquid based maceration extraction, guanidinium ionic liquid based heat reflux extraction and guanidinium ionic liquid based ultrasound-assisted extraction. The precision, stability, and repeatability of the process were investigated. The mechanisms of guanidinium ionic liquid based microwave-assisted extraction were researched by scanning electron microscopy and IR spectroscopy. All the results show that guanidinium ionic liquid based microwave-assisted extraction has a huge potential in the extraction of bioactive compounds from complex samples. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Visual tracking of da Vinci instruments for laparoscopic surgery
NASA Astrophysics Data System (ADS)
Speidel, S.; Kuhn, E.; Bodenstedt, S.; Röhl, S.; Kenngott, H.; Müller-Stich, B.; Dillmann, R.
2014-03-01
Intraoperative tracking of laparoscopic instruments is a prerequisite to realize further assistance functions. Since endoscopic images are always available, this sensor input can be used to localize the instruments without special devices or robot kinematics. In this paper, we present an image-based markerless 3D tracking of different da Vinci instruments in near real-time without an explicit model. The method is based on different visual cues to segment the instrument tip, calculates a tip point and uses a multiple object particle filter for tracking. The accuracy and robustness is evaluated with in vivo data.
a Web-Based Interactive Tool for Multi-Resolution 3d Models of a Maya Archaeological Site
NASA Astrophysics Data System (ADS)
Agugiaro, G.; Remondino, F.; Girardi, G.; von Schwerin, J.; Richards-Rissetto, H.; De Amicis, R.
2011-09-01
Continuous technological advances in surveying, computing and digital-content delivery are strongly contributing to a change in the way Cultural Heritage is "perceived": new tools and methodologies for documentation, reconstruction and research are being created to assist not only scholars, but also to reach more potential users (e.g. students and tourists) willing to access more detailed information about art history and archaeology. 3D computer-simulated models, sometimes set in virtual landscapes, offer for example the chance to explore possible hypothetical reconstructions, while on-line GIS resources can help interactive analyses of relationships and change over space and time. While for some research purposes a traditional 2D approach may suffice, this is not the case for more complex analyses concerning spatial and temporal features of architecture, like for example the relationship of architecture and landscape, visibility studies etc. The project aims therefore at creating a tool, called "QueryArch3D" tool, which enables the web-based visualisation and queries of an interactive, multi-resolution 3D model in the framework of Cultural Heritage. More specifically, a complete Maya archaeological site, located in Copan (Honduras), has been chosen as case study to test and demonstrate the platform's capabilities. Much of the site has been surveyed and modelled at different levels of detail (LoD) and the geometric model has been semantically segmented and integrated with attribute data gathered from several external data sources. The paper describes the characteristics of the research work, along with its implementation issues and the initial results of the developed prototype.
Highlighting the medical applications of 3D printing in Egypt
Abdelghany, Khaled; Hamza, Hosamuddin
2015-01-01
Computer-assisted designing/computer-assisted manufacturing (CAD/CAM) technology has enabled medical practitioners to tailor physical models in a patient and purpose-specific fashion. It allows the designing and manufacturing of templates, appliances and devices with a high range of accuracy using biocompatible materials. The technique, nevertheless, relies on digital scanning (e.g., using intraoral scanners) and/or digital imaging (e.g., CT and MRI). In developing countries, there are some technical and financial limitations of implementing such advanced tools as an essential portion of medical applications. This paper focuses on the surgical and dental use of 3D printing technology in Egypt as a developing country. PMID:26807414
3D endoscopic imaging using structured illumination technique (Conference Presentation)
NASA Astrophysics Data System (ADS)
Le, Hanh N. D.; Nguyen, Hieu; Wang, Zhaoyang; Kang, Jin U.
2017-02-01
Surgeons have been increasingly relying on minimally invasive surgical guidance techniques not only to reduce surgical trauma but also to achieve accurate and objective surgical risk evaluations. A typical minimally invasive surgical guidance system provides visual assistance in two-dimensional anatomy and pathology of internal organ within a limited field of view. In this work, we propose and implement a structure illumination endoscope to provide a simple, inexpensive 3D endoscopic imaging to conduct high resolution 3D imagery for use in surgical guidance system. The system is calibrated and validated for quantitative depth measurement in both calibrated target and human subject. The system exhibits a depth of field of 20 mm, depth resolution of 0.2mm and a relative accuracy of 0.1%. The demonstrated setup affirms the feasibility of using the structured illumination endoscope for depth quantization and assisting medical diagnostic assessments
Perrotta, Alberto; Fuentes-Hernandez, Canek; Khan, Talha M.; ...
2016-12-02
Plasma-assisted atomic layer deposition (ALD) is used for the deposition of environmental barriers directly onto organic photovoltaic devices (OPVs) at near room temperature (30 °C). To study the effect of the ALD process on the organic materials forming the device, the precursor diffusion and intermixing at the interface during the growth of different plasma- assisted ALD inorganic barriers (i.e. Al2O3 and TiO2) onto the organic photoactive layer (P3HT:ICBA) was investigated. Depth profile x-ray photoelectron spectroscopy was used to analyze the composition of the organic/inorganic interface to investigate the infiltration of the plasma-assisted ALD precursors into the photoactive layer as amore » function of the precursor dimension, the process temperature, and organic layer morphology. The free volume in the photoactive layer accessible to the ALD precursor was characterized by means of ellipsometric porosimetry (EP) and spectroscopic ellipsometry as a function of temperature. The organic layer is shown to exhibit free volume broadening at high temperatures, increasing the infiltration depth of the ALD precursor into the photoactive layer. Furthermore, based on previous investigations, the intrinsic permeation properties of the inorganic layers deposited by plasma-assisted ALD were predicted from the nano-porosity content as measured by EP and found to be in the 10-6 gm-2 d-1 range. Insight from our studies was used to design and fabricate multilayer barriers synthesized at near-room temperature by plasma-assisted ALD in combination with plasma-enhanced CVD onto organic photovoltaic (OPVs) devices. Encapsulated OPVs displayed shelf-lifetimes up to 1400 h at ambient conditions.« less
78 FR 73202 - Exercise of Authority Under the Immigration and Nationality Act; Correction
Federal Register 2010, 2011, 2012, 2013, 2014
2013-12-05
... Immigration and Nationality Act; Correction AGENCY: Office of the Secretary, DHS. ACTION: Notice; correction... determination under section 212(d)(3)(B)(i) of the Immigration and Nationality Act, 8 U.S.C. 1182(d)(3)(B)(i... FURTHER INFORMATION CONTACT: Nicholas J. Perry, Assistant General Counsel for Immigration Enforcement...
Endocavity Ultrasound Probe Manipulators
Stoianovici, Dan; Kim, Chunwoo; Schäfer, Felix; Huang, Chien-Ming; Zuo, Yihe; Petrisor, Doru; Han, Misop
2014-01-01
We developed two similar structure manipulators for medical endocavity ultrasound probes with 3 and 4 degrees of freedom (DoF). These robots allow scanning with ultrasound for 3-D imaging and enable robot-assisted image-guided procedures. Both robots use remote center of motion kinematics, characteristic of medical robots. The 4-DoF robot provides unrestricted manipulation of the endocavity probe. With the 3-DoF robot the insertion motion of the probe must be adjusted manually, but the device is simpler and may also be used to manipulate external-body probes. The robots enabled a novel surgical approach of using intraoperative image-based navigation during robot-assisted laparoscopic prostatectomy (RALP), performed with concurrent use of two robotic systems (Tandem, T-RALP). Thus far, a clinical trial for evaluation of safety and feasibility has been performed successfully on 46 patients. This paper describes the architecture and design of the robots, the two prototypes, control features related to safety, preclinical experiments, and the T-RALP procedure. PMID:24795525
Nano-soldering of magnetically aligned three-dimensional nanowire networks.
Gao, Fan; Gu, Zhiyong
2010-03-19
It is extremely challenging to fabricate 3D integrated nanostructures and hybrid nanoelectronic devices. In this paper, we report a simple and efficient method to simultaneously assemble and solder nanowires into ordered 3D and electrically conductive nanowire networks. Nano-solders such as tin were fabricated onto both ends of multi-segmented nanowires by a template-assisted electrodeposition method. These nanowires were then self-assembled and soldered into large-scale 3D network structures by magnetic field assisted assembly in a liquid medium with a high boiling point. The formation of junctions/interconnects between the nanowires and the scale of the assembly were dependent on the solder reflow temperature and the strength of the magnetic field. The size of the assembled nanowire networks ranged from tens of microns to millimeters. The electrical characteristics of the 3D nanowire networks were measured by regular current-voltage (I-V) measurements using a probe station with micropositioners. Nano-solders, when combined with assembling techniques, can be used to efficiently connect and join nanowires with low contact resistance, which are very well suited for sensor integration as well as nanoelectronic device fabrication.
Klapan, Ivica; Vranjes, Zeljko; Prgomet, Drago; Lukinović, Juraj
2008-03-01
The real-time requirement means that the simulation should be able to follow the actions of the user that may be moving in the virtual environment. The computer system should also store in its memory a three-dimensional (3D) model of the virtual environment. In that case a real-time virtual reality system will update the 3D graphic visualization as the user moves, so that up-to-date visualization is always shown on the computer screen. Upon completion of the tele-operation, the surgeon compares the preoperative and postoperative images and models of the operative field, and studies video records of the procedure itself Using intraoperative records, animated images of the real tele-procedure performed can be designed. Virtual surgery offers the possibility of preoperative planning in rhinology. The intraoperative use of computer in real time requires development of appropriate hardware and software to connect medical instrumentarium with the computer and to operate the computer by thus connected instrumentarium and sophisticated multimedia interfaces.
Tu, Zhengyuan; Wu, Menghao; Zeng, Xiao Cheng
2017-05-04
Coexistence of ferromagnetism and ferroelectricity in a single 2D material is highly desirable for integration of multifunctional units in 2D material-based circuits. We report theoretical evidence of C 6 N 8 H organic network as being the first 2D organic multiferroic material with coexisting ferromagnetic and ferroelectric properties. The ferroelectricity stems from multimode proton-transfer within the 2D C 6 N 8 H network, in which a long-range proton-transfer mode is enabled by the facilitation of oxygen molecule when the network is exposed to the air. Such oxygen-assisted ferroelectricity also leads to a high Curie temperature and coupling between ferroelectricity and ferromagnetism. We also find that hydrogenation and carbon doping can transform the 2D g-C 3 N 4 network from an insulator to an n-type/p-type magnetic semiconductor with modest bandgap. Akin to the dopant induced n/p channels in silicon wafer, a variety of dopant created functional units can be integrated into the g-C 3 N 4 wafer by design for nanoelectronic applications.
22 CFR 141.3 - Discrimination prohibited.
Code of Federal Regulations, 2010 CFR
2010-04-01
...) Where a primary objective of the Federal financial assistance to a program to which this part applies is... facilities), including programs where a primary objective of the Federal financial assistance is: (i) To... program as an employee in accordance with paragraph (d) of this section. (vii) Deny a person the...
Strategic Studies Quarterly. Volume 2, Number 3, Fall 2008
2008-01-01
Managing Editor Betty R. Littlejohn, Editorial Assistant Jerry L. Gantt, Content Editor Sherry Terrell , Editorial Assistant Steven C. Garst...factsheet.asp?id=107 . Ibid. 9. Lt Col Sebastian M. Convertino II, CDR Lou Anne DeMattei, and Lt Col Tammy Knierim, Flying and Fighting in...PhD, Editor-in-Chief L. Tawanda Eaves, Managing Editor Betty R. Littlejohn, Editorial Assistant Jerry L. Gantt, Content Editor Sherry Terrell
Housing Assistance and Blood Lead Levels: Children in the United States, 2005-2012.
Ahrens, Katherine A; Haley, Barbara A; Rossen, Lauren M; Lloyd, Patricia C; Aoki, Yutaka
2016-11-01
To compare blood lead levels (BLLs) among US children aged 1 to 5 years according to receipt of federal housing assistance. In our analyses, we used 2005 to 2012 data for National Health and Nutrition Examination Survey (NHANES) respondents that were linked to 1999 to 2014 administrative records from the US Department of Housing and Urban Development (HUD). After we restricted the analysis to children with family income-to-poverty ratios below 200%, we compared geometric mean BLLs and the prevalence of BLLs of 3 micrograms per deciliter or higher among children who were living in assisted housing at the time of their NHANES blood draw (n = 151) with data for children who did not receive housing assistance (n = 1099). After adjustment, children living in assisted housing had a significantly lower geometric mean BLL (1.44 µg/dL; 95% confidence interval [CI] = 1.31, 1.57) than comparable children who did not receive housing assistance (1.79 µg/dL; 95% CI = 1.59, 2.01; P < .01). The prevalence ratio for BLLs of 3 micrograms per deciliter or higher was 0.51 (95% CI = 0.33, 0.81; P < .01). Children aged 1 to 5 years during 2005 to 2012 who were living in HUD-assisted housing had lower BLLs than expected given their demographic, socioeconomic, and family characteristics.
Application requirements for Robotic Nursing Assistants in hospital environments
NASA Astrophysics Data System (ADS)
Cremer, Sven; Doelling, Kris; Lundberg, Cody L.; McNair, Mike; Shin, Jeongsik; Popa, Dan
2016-05-01
In this paper we report on analysis toward identifying design requirements for an Adaptive Robotic Nursing Assistant (ARNA). Specifically, the paper focuses on application requirements for ARNA, envisioned as a mobile assistive robot that can navigate hospital environments to perform chores in roles such as patient sitter and patient walker. The role of a sitter is primarily related to patient observation from a distance, and fetching objects at the patient's request, while a walker provides physical assistance for ambulation and rehabilitation. The robot will be expected to not only understand nurse and patient intent but also close the decision loop by automating several routine tasks. As a result, the robot will be equipped with sensors such as distributed pressure sensitive skins, 3D range sensors, and so on. Modular sensor and actuator hardware configured in the form of several multi-degree-of-freedom manipulators, and a mobile base are expected to be deployed in reconfigurable platforms for physical assistance tasks. Furthermore, adaptive human-machine interfaces are expected to play a key role, as they directly impact the ability of robots to assist nurses in a dynamic and unstructured environment. This paper discusses required tasks for the ARNA robot, as well as sensors and software infrastructure to carry out those tasks in the aspects of technical resource availability, gaps, and needed experimental studies.
Yao, Fei; Wang, Jian; Yao, Ju; Hang, Fangrong; Lei, Xu; Cao, Yongke
2017-03-01
The aim of this retrospective study was to evaluate the practice and the feasibility of Osirix, a free and open-source medical imaging software, in performing accurate video-assisted thoracoscopic lobectomy and segmentectomy. From July 2014 to April 2016, 63 patients received anatomical video-assisted thoracoscopic surgery (VATS), either lobectomy or segmentectomy, in our department. Three-dimensional (3D) reconstruction images of 61 (96.8%) patients were preoperatively obtained with contrast-enhanced computed tomography (CT). Preoperative resection simulations were accomplished with patient-individual reconstructed 3D images. For lobectomy, pulmonary lobar veins, arteries and bronchi were identified meticulously by carefully reviewing the 3D images on the display. For segmentectomy, the intrasegmental veins in the affected segment for division and the intersegmental veins to be preserved were identified on the 3D images. Patient preoperative characteristics, surgical outcomes and postoperative data were reviewed from a prospective database. The study cohort of 63 patients included 33 (52.4%) men and 30 (47.6%) women, of whom 46 (73.0%) underwent VATS lobectomy and 17 (27.0%) underwent VATS segmentectomy. There was 1 conversion from VATS lobectomy to open thoracotomy because of fibrocalcified lymph nodes. A VATS lobectomy was performed in 1 case after completing the segmentectomy because invasive adenocarcinoma was detected by intraoperative frozen-section analysis. There were no 30-day or 90-day operative mortalities CONCLUSIONS: The free, simple, and user-friendly software program Osirix can provide a 3D anatomic structure of pulmonary vessels and a clear vision into the space between the lesion and adjacent tissues, which allows surgeons to make preoperative simulations and improve the accuracy and safety of actual surgery. Copyright © 2017 IJS Publishing Group Ltd. Published by Elsevier Ltd. All rights reserved.
Situation Model for Situation-Aware Assistance of Dementia Patients in Outdoor Mobility
Yordanova, Kristina; Koldrack, Philipp; Heine, Christina; Henkel, Ron; Martin, Mike; Teipel, Stefan; Kirste, Thomas
2017-01-01
Background: Dementia impairs spatial orientation and route planning, thus often affecting the patient’s ability to move outdoors and maintain social activities. Situation-aware deliberative assistive technology devices (ATD) can substitute impaired cognitive function in order to maintain one’s level of social activity. To build such a system, one needs domain knowledge about the patient’s situation and needs. We call this collection of knowledge situation model. Objective: To construct a situation model for the outdoor mobility of people with dementia (PwD). The model serves two purposes: 1) as a knowledge base from which to build an ATD describing the mobility of PwD; and 2) as a codebook for the annotation of the recorded behavior. Methods: We perform systematic knowledge elicitation to obtain the relevant knowledge. The OBO Edit tool is used for implementing and validating the situation model. The model is evaluated by using it as a codebook for annotating the behavior of PwD during a mobility study and interrater agreement is computed. In addition, clinical experts perform manual evaluation and curation of the model. Results: The situation model consists of 101 concepts with 11 relation types between them. The results from the annotation showed substantial overlapping between two annotators (Cohen’s kappa of 0.61). Conclusion: The situation model is a first attempt to systematically collect and organize information related to the outdoor mobility of PwD for the purposes of situation-aware assistance. The model is the base for building an ATD able to provide situation-aware assistance and to potentially improve the quality of life of PwD. PMID:29060937
Accurate 3D kinematic measurement of temporomandibular joint using X-ray fluoroscopic images
NASA Astrophysics Data System (ADS)
Yamazaki, Takaharu; Matsumoto, Akiko; Sugamoto, Kazuomi; Matsumoto, Ken; Kakimoto, Naoya; Yura, Yoshiaki
2014-04-01
Accurate measurement and analysis of 3D kinematics of temporomandibular joint (TMJ) is very important for assisting clinical diagnosis and treatment of prosthodontics and orthodontics, and oral surgery. This study presents a new 3D kinematic measurement technique of the TMJ using X-ray fluoroscopic images, which can easily obtain the TMJ kinematic data in natural motion. In vivo kinematics of the TMJ (maxilla and mandibular bone) is determined using a feature-based 2D/3D registration, which uses beads silhouette on fluoroscopic images and 3D surface bone models with beads. The 3D surface models of maxilla and mandibular bone with beads were created from CT scans data of the subject using the mouthpiece with the seven strategically placed beads. In order to validate the accuracy of pose estimation for the maxilla and mandibular bone, computer simulation test was performed using five patterns of synthetic tantalum beads silhouette images. In the clinical applications, dynamic movement during jaw opening and closing was conducted, and the relative pose of the mandibular bone with respect to the maxilla bone was determined. The results of computer simulation test showed that the root mean square errors were sufficiently smaller than 1.0 mm and 1.0 degree. In the results of clinical application, during jaw opening from 0.0 to 36.8 degree of rotation, mandibular condyle exhibited 19.8 mm of anterior sliding relative to maxillary articular fossa, and these measurement values were clinically similar to the previous reports. Consequently, present technique was thought to be suitable for the 3D TMJ kinematic analysis.
A Neural Network Based Workstation for Automated Cell Proliferation Analysis
2001-10-25
work was supported by the Programa de Apoyo a Proyectos de Desarrollo e Investigacíon en Informática REDII 2000. We thank Blanca Itzel Taboada for...Meléndez1, G. Corkidi.2 1Centro de Instrumentos, UNAM. P.O. Box 70-186, México 04510, D.F. 2Instituto de Biotecnología, UNAM. P.O. Box 510-3, 62250...proliferation analysis, of cytological microscope images. The software of the system assists the expert biotechnologist during cell proliferation and
Quantitative 3-D imaging topogrammetry for telemedicine applications
NASA Technical Reports Server (NTRS)
Altschuler, Bruce R.
1994-01-01
The technology to reliably transmit high-resolution visual imagery over short to medium distances in real time has led to the serious considerations of the use of telemedicine, telepresence, and telerobotics in the delivery of health care. These concepts may involve, and evolve toward: consultation from remote expert teaching centers; diagnosis; triage; real-time remote advice to the surgeon; and real-time remote surgical instrument manipulation (telerobotics with virtual reality). Further extrapolation leads to teledesign and telereplication of spare surgical parts through quantitative teleimaging of 3-D surfaces tied to CAD/CAM devices and an artificially intelligent archival data base of 'normal' shapes. The ability to generate 'topogrames' or 3-D surface numerical tables of coordinate values capable of creating computer-generated virtual holographic-like displays, machine part replication, and statistical diagnostic shape assessment is critical to the progression of telemedicine. Any virtual reality simulation will remain in 'video-game' realm until realistic dimensional and spatial relational inputs from real measurements in vivo during surgeries are added to an ever-growing statistical data archive. The challenges of managing and interpreting this 3-D data base, which would include radiographic and surface quantitative data, are considerable. As technology drives toward dynamic and continuous 3-D surface measurements, presenting millions of X, Y, Z data points per second of flexing, stretching, moving human organs, the knowledge base and interpretive capabilities of 'brilliant robots' to work as a surgeon's tireless assistants becomes imaginable. The brilliant robot would 'see' what the surgeon sees--and more, for the robot could quantify its 3-D sensing and would 'see' in a wider spectral range than humans, and could zoom its 'eyes' from the macro world to long-distance microscopy. Unerring robot hands could rapidly perform machine-aided suturing with precision micro-sewing machines, splice neural connections with laser welds, micro-bore through constricted vessels, and computer combine ultrasound, microradiography, and 3-D mini-borescopes to quickly assess and trace vascular problems in situ. The spatial relationships between organs, robotic arms, and end-effector diagnostic, manipulative, and surgical instruments would be constantly monitored by the robot 'brain' using inputs from its multiple 3-D quantitative 'eyes' remote sensing, as well as by contact and proximity force measuring devices. Methods to create accurate and quantitative 3-D topograms at continuous video data rates are described.
32 CFR 21.510 - Why does the DoD report information to the CFDA?
Code of Federal Regulations, 2011 CFR
2011-07-01
... maintaining the Federal Assistance Programs Retrieval System, a computerized data base of the information. 4... 32 National Defense 1 2011-07-01 2011-07-01 false Why does the DoD report information to the CFDA... GRANT AND AGREEMENT REGULATIONS DoD GRANTS AND AGREEMENTS-GENERAL MATTERS Information Reporting on...
32 CFR 21.510 - Why does the DoD report information to the CFDA?
Code of Federal Regulations, 2010 CFR
2010-07-01
... maintaining the Federal Assistance Programs Retrieval System, a computerized data base of the information. 4... 32 National Defense 1 2010-07-01 2010-07-01 false Why does the DoD report information to the CFDA... GRANT AND AGREEMENT REGULATIONS DoD GRANTS AND AGREEMENTS-GENERAL MATTERS Information Reporting on...
32 CFR 21.510 - Why does the DoD report information to the CFDA?
Code of Federal Regulations, 2013 CFR
2013-07-01
... maintaining the Federal Assistance Programs Retrieval System, a computerized data base of the information. 4... 32 National Defense 1 2013-07-01 2013-07-01 false Why does the DoD report information to the CFDA... GRANT AND AGREEMENT REGULATIONS DoD GRANTS AND AGREEMENTS-GENERAL MATTERS Information Reporting on...
32 CFR 21.510 - Why does the DoD report information to the CFDA?
Code of Federal Regulations, 2014 CFR
2014-07-01
... maintaining the Federal Assistance Programs Retrieval System, a computerized data base of the information. 4... 32 National Defense 1 2014-07-01 2014-07-01 false Why does the DoD report information to the CFDA... GRANT AND AGREEMENT REGULATIONS DoD GRANTS AND AGREEMENTS-GENERAL MATTERS Information Reporting on...
32 CFR 21.510 - Why does the DoD report information to the CFDA?
Code of Federal Regulations, 2012 CFR
2012-07-01
... maintaining the Federal Assistance Programs Retrieval System, a computerized data base of the information. 4... 32 National Defense 1 2012-07-01 2012-07-01 false Why does the DoD report information to the CFDA... GRANT AND AGREEMENT REGULATIONS DoD GRANTS AND AGREEMENTS-GENERAL MATTERS Information Reporting on...
3D visualization of movements can amplify motor cortex activation during subsequent motor imagery
Sollfrank, Teresa; Hart, Daniel; Goodsell, Rachel; Foster, Jonathan; Tan, Tele
2015-01-01
A repetitive movement practice by motor imagery (MI) can influence motor cortical excitability in the electroencephalogram (EEG). This study investigated if a realistic visualization in 3D of upper and lower limb movements can amplify motor related potentials during subsequent MI. We hypothesized that a richer sensory visualization might be more effective during instrumental conditioning, resulting in a more pronounced event related desynchronization (ERD) of the upper alpha band (10–12 Hz) over the sensorimotor cortices thereby potentially improving MI based brain-computer interface (BCI) protocols for motor rehabilitation. The results show a strong increase of the characteristic patterns of ERD of the upper alpha band components for left and right limb MI present over the sensorimotor areas in both visualization conditions. Overall, significant differences were observed as a function of visualization modality (VM; 2D vs. 3D). The largest upper alpha band power decrease was obtained during MI after a 3-dimensional visualization. In total in 12 out of 20 tasks the end-user of the 3D visualization group showed an enhanced upper alpha ERD relative to 2D VM group, with statistical significance in nine tasks.With a realistic visualization of the limb movements, we tried to increase motor cortex activation during subsequent MI. The feedback and the feedback environment should be inherently motivating and relevant for the learner and should have an appeal of novelty, real-world relevance or aesthetic value (Ryan and Deci, 2000; Merrill, 2007). Realistic visual feedback, consistent with the participant’s MI, might be helpful for accomplishing successful MI and the use of such feedback may assist in making BCI a more natural interface for MI based BCI rehabilitation. PMID:26347642
3D visualization of movements can amplify motor cortex activation during subsequent motor imagery.
Sollfrank, Teresa; Hart, Daniel; Goodsell, Rachel; Foster, Jonathan; Tan, Tele
2015-01-01
A repetitive movement practice by motor imagery (MI) can influence motor cortical excitability in the electroencephalogram (EEG). This study investigated if a realistic visualization in 3D of upper and lower limb movements can amplify motor related potentials during subsequent MI. We hypothesized that a richer sensory visualization might be more effective during instrumental conditioning, resulting in a more pronounced event related desynchronization (ERD) of the upper alpha band (10-12 Hz) over the sensorimotor cortices thereby potentially improving MI based brain-computer interface (BCI) protocols for motor rehabilitation. The results show a strong increase of the characteristic patterns of ERD of the upper alpha band components for left and right limb MI present over the sensorimotor areas in both visualization conditions. Overall, significant differences were observed as a function of visualization modality (VM; 2D vs. 3D). The largest upper alpha band power decrease was obtained during MI after a 3-dimensional visualization. In total in 12 out of 20 tasks the end-user of the 3D visualization group showed an enhanced upper alpha ERD relative to 2D VM group, with statistical significance in nine tasks.With a realistic visualization of the limb movements, we tried to increase motor cortex activation during subsequent MI. The feedback and the feedback environment should be inherently motivating and relevant for the learner and should have an appeal of novelty, real-world relevance or aesthetic value (Ryan and Deci, 2000; Merrill, 2007). Realistic visual feedback, consistent with the participant's MI, might be helpful for accomplishing successful MI and the use of such feedback may assist in making BCI a more natural interface for MI based BCI rehabilitation.
Attribute classification for generating GPR facies models
NASA Astrophysics Data System (ADS)
Tronicke, Jens; Allroggen, Niklas
2017-04-01
Ground-penetrating radar (GPR) is an established geophysical tool to explore near-surface sedimentary environments. It has been successfully used, for example, to reconstruct past depositional environments, to investigate sedimentary processes, to aid hydrogeological investigations, and to assist in hydrocarbon reservoir analog studies. Interpreting such 2D/3D GPR data, usually relies on concepts known as GPR facies analysis, in which GPR facies are defined as units composed of characteristic reflection patterns (in terms of reflection amplitude, continuity, geometry, and internal configuration). The resulting facies models are then interpreted in terms of depositional processes, sedimentary environments, litho-, and hydrofacies. Typically, such GPR facies analyses are implemented in a manual workflow being laborious and rather inefficient especially for 3D data sets. In addition, such a subjective strategy bears the potential of inconsistency because the outcome depends on the expertise and experience of the interpreter. In this presentation, we investigate the feasibility of delineating GPR facies in an objective and largely automated manner. Our proposed workflow relies on a three-step procedure. First, we calculate a variety of geometrical and physical attributes from processed 2D and 3D GPR data sets. Then, we analyze and evaluate this attribute data base (e.g., using statistical tools such as principal component analysis) to reduce its dimensionality and to avoid redundant information, respectively. Finally, we integrate the reduced data base using tools such as composite imaging, cluster analysis, and neural networks. Using field examples that have been acquired across different depositional environments, we demonstrate that the resulting 2D/3D facies models ease and improve the interpretation of GPR data. We conclude that our interpretation strategy allows to generate GPR facies models in a consistent and largely automated manner and might be helpful in variety near-surface applications.
Posterior tibial slope in medial opening-wedge high tibial osteotomy: 2-D versus 3-D navigation.
Yim, Ji Hyeon; Seon, Jong Keun; Song, Eun Kyoo
2012-10-01
Although opening-wedge high tibial osteotomy (HTO) is used to correct deformities, it can simultaneously alter tibial slope in the sagittal plane because of the triangular configuration of the proximal tibia, and this undesired change in tibial slope can influence knee kinematics, stability, and joint contact pressure. Therefore, medial opening-wedge HTO is a technically demanding procedure despite the use of 2-dimensional (2-D) navigation. The authors evaluated the posterior tibial slope pre- and postoperatively in patients who underwent navigation-assisted opening-wedge HTO and compared posterior slope changes for 2-D and 3-dimensional (3-D) navigation versions. Patients were randomly divided into 2 groups based on the navigation system used: group A (2-D guidance for coronal alignment; 17 patients) and group B (3-D guidance for coronal and sagittal alignments; 17 patients). Postoperatively, the mechanical axis was corrected to a mean valgus of 2.81° (range, 1°-5.4°) in group A and 3.15° (range, 1.5°-5.6°) in group B. A significant intergroup difference existed for the amount of posterior tibial slope change (Δ slope) pre- and postoperatively (P=.04).Opening-wedge HTO using navigation offers accurate alignment of the lower limb. In particular, the use of 3-D navigation results in significantly less change in the posterior tibial slope postoperatively than does the use of 2-D navigation. Accordingly, the authors recommend the use of 3-D navigation systems because they provide real-time intraoperative information about coronal, sagittal, and transverse axes and guide the maintenance of the native posterior tibial slope. Copyright 2012, SLACK Incorporated.
Anchorage in Orthodontics: Three-dimensional Scanner Input.
Nabbout, Fidele; Baron, Pascal
2018-01-01
The aim of this article is to re-evaluate anchorage coefficient values in orthodontics and their influence in the treatment decision through the usage of three-dimensional (3D) scanner. A sample of 80 patients was analyzed with the 3D scanner using the C2000 and Cepha 3DT softwares (CIRAD Montpellier, France). Tooth anatomy parameters (linear measurements, root, and crown volumes) were then calculated to determine new anchorage coefficients based on root volume. Data were collected and statistically evaluated with the StatView software (version 5.0). The anchorage coefficient values found in this study are compared to those established in previous studies. These new values affect and modify our approach in orthodontic treatment from the standpoint of anchorage. The use of new anchorage coefficient values has significant clinical implications in conventional and in microimplants-assisted orthodontic mechanics through the selection and delivery of the optimal force system (magnitude and moment) for an adequate biological response.
Wu, Longkun; Wang, Limin; Qi, Baokun; Zhang, Xiaonan; Chen, Fusheng; Li, Yang; Sui, Xiaonan; Jiang, Lianzhou
2018-05-30
The understanding of the structure morphology of oil-rich emulsion from enzyme-assisted extraction processing (EAEP) was a critical step to break the oil-rich emulsion structure in order to recover oil. Albeit EAEP method has been applied as an alternative way to conventional solvent extraction method, the structure morphology of oil-rich emulsion was still unclear. The current study aimed to investigate the structure morphology of oil-rich emulsion from EAEP using 3D confocal Raman imaging technique. With increasing the enzymatic hydrolysis duration from 1 to 3 h, the stability of oil-rich emulsion was decreased as visualized in the 3D confocal Raman images that the protein and oil were mixed together. The subsequent Raman spectrum analysis further revealed that the decreased stability of oil-rich emulsion was due to the protein aggregations via SS bonds or protein-lipid interactions. The conformational transfer in protein indicated the formation of a compact structure. Copyright © 2017 Elsevier Ltd. All rights reserved.
Baronio, Gabriele; Volonghi, Paola; Signoroni, Alberto
2017-01-01
In the rehabilitation field, the use of additive manufacturing techniques to realize customized orthoses is increasingly widespread. Obtaining a 3D model for the 3D printing phase can be done following different methodologies. We consider the creation of personalized upper limb orthoses, also including fingers, starting from the acquisition of the hand geometry through accurate 3D scanning. However, hand scanning procedure presents differences between healthy subjects and patients affected by pathologies that compromise upper limb functionality. In this work, we present the concept and design of a 3D printed support to assist hand scanning of such patients. The device, realized with FDM additive manufacturing techniques in ABS material, allows palmar acquisitions, and its design and test are motivated by the following needs: (1) immobilizing the hand of patients during the palmar scanning to reduce involuntary movements affecting the scanning quality and (2) keeping hands open and in a correct position, especially to contrast the high degree of hypertonicity of spastic subjects. The resulting device can be used indifferently for the right and the left hand; it is provided in four-dimensional sizes and may be also suitable as a palmar support for the acquisition of the dorsal side of the hand.
Volonghi, Paola
2017-01-01
In the rehabilitation field, the use of additive manufacturing techniques to realize customized orthoses is increasingly widespread. Obtaining a 3D model for the 3D printing phase can be done following different methodologies. We consider the creation of personalized upper limb orthoses, also including fingers, starting from the acquisition of the hand geometry through accurate 3D scanning. However, hand scanning procedure presents differences between healthy subjects and patients affected by pathologies that compromise upper limb functionality. In this work, we present the concept and design of a 3D printed support to assist hand scanning of such patients. The device, realized with FDM additive manufacturing techniques in ABS material, allows palmar acquisitions, and its design and test are motivated by the following needs: (1) immobilizing the hand of patients during the palmar scanning to reduce involuntary movements affecting the scanning quality and (2) keeping hands open and in a correct position, especially to contrast the high degree of hypertonicity of spastic subjects. The resulting device can be used indifferently for the right and the left hand; it is provided in four-dimensional sizes and may be also suitable as a palmar support for the acquisition of the dorsal side of the hand. PMID:29234219
Alió Del Barrio, Jorge L; Tiveron, Mauro; Plaza-Puche, Ana B; Amesty, María A; Casanova, Laura; García, María J; Alió, Jorge L
2017-10-18
To evaluate the visual outcomes after femtosecond laser-assisted laser in situ keratomileusis (LASIK) surgery to correct primary compound hyperopic astigmatism with high cylinder using a fast repetition rate excimer laser platform with optimized aspheric profiles and cyclotorsion control. Eyes with primary simple or compound hyperopic astigmatism and a cylinder power ≥3.00 D had uneventful femtosecond laser-assisted LASIK with a fast repetition rate excimer laser ablation, aspheric profiles, and cyclotorsion control. Visual, refractive, and aberrometric results were evaluated at the 3- and 6-month follow-up. The astigmatic outcome was evaluated using the Alpins method and ASSORT software. This study enrolled 80 eyes at 3 months and 50 eyes at 6 months. The significant reduction in refractive sphere and cylinder 3 and 6 months postoperatively (p<0.01) was associated with an improved uncorrected distance visual acuity (p<0.01). A total of 23.75% required retreatment 3 months after surgery. Efficacy and safety indices at 6 months were 0.90 and 1.00, respectively. At 6 months, 80% of eyes had an SE within ±0.50 D and 96% within ±1.00 D. No significant differences were detected between the third and the sixth postoperative months in refractive parameters. A significant increase in the spherical aberration was detected, but not in coma. The correction index was 0.94 at 3 months. Laser in situ keratomileusis for primary compound hyperopic astigmatism with high cylinder (>3.00 D) using the latest excimer platforms with cyclotorsion control, fast repetition rate, and optimized aspheric profiles is safe, moderately effective, and predictable.
Computational fluid dynamics (CFD) study on the fetal aortic coarctation
NASA Astrophysics Data System (ADS)
Zhou, Yue; Zhang, Yutao; Wang, Jingying
2018-03-01
Blood flows in normal and coarctate fetal aortas are simulated by the CFD technique using T-rex grids. The three-dimensional (3-D) digital model of the fetal arota is reconstructed by the computer-aided design (CAD) software based on two-dimensional (2-D) ultrasono tomographic images. Simulation results displays the development and enhancement of the secondary flow structure in the coarctate fetal arota. As the diameter narrow ratio rises greater than 45%, the pressure and wall shear stress (WSS) of the aorta arch increase exponentially, which is consistent with the conventional clinical concept. The present study also demonstrates that CFD is a very promising assistant technique to investigate human cardiovascular diseases.
Li, M Y; Yang, H F; Zhang, Z H; Gu, J H; Yang, S H
2016-06-08
A universally applicable method for promoting the fast formation and growth of high-density Sn whiskers on solders was developed by fabricating Mg/Sn-based solder/Mg joints using ultrasonic-assisted soldering at 250 °C for 6 s and then subjected to thermal aging at 25 °C for 7 d. The results showed that the use of the ultrasonic-assisted soldering could produce the supersaturated dissolution of Mg in the liquid Sn and lead to the existence of two forms of Mg in Sn after solidification. Moreover, the formation and growth of the high-density whiskers were facilitated by the specific contributions of both of the Mg forms in the solid Sn. Specifically, interstitial Mg can provide the persistent driving force for Sn whisker growth, whereas the Mg2Sn phase can increase the formation probability of Sn whiskers. In addition, we presented that the formation and growth of Sn whiskers in the Sn-based solders can be significantly restricted by a small amount of Zn addition (≥3 wt.%), and the prevention mechanisms are attributed to the segregation of Zn atoms at grain or phase boundaries and the formation of the lamellar-type Zn-rich structures in the solder.
Finelle, Gary; Lee, Sang J
Digital technology has been widely used in the field of implant dentistry. From a surgical standpoint, computer-guided surgery can be utilized to enhance primary implant stability and to improve the precision of implant placement. From a prosthetic standpoint, computer-aided design/computer-assisted manufacture (CAD/CAM) technology has brought about various restorative options, including the fabrication of customized abutments through a virtual design based on computer-guided surgical planning. This case report describes a novel technique combining the use of a three-dimensional (3D) printed surgical template for the immediate placement of an implant, with CAD/CAM technology to optimize hard and soft tissue healing after bone grafting with the use of a socket sealing abutment.
3D imaging, 3D printing and 3D virtual planning in endodontics.
Shah, Pratik; Chong, B S
2018-03-01
The adoption and adaptation of recent advances in digital technology, such as three-dimensional (3D) printed objects and haptic simulators, in dentistry have influenced teaching and/or management of cases involving implant, craniofacial, maxillofacial, orthognathic and periodontal treatments. 3D printed models and guides may help operators plan and tackle complicated non-surgical and surgical endodontic treatment and may aid skill acquisition. Haptic simulators may assist in the development of competency in endodontic procedures through the acquisition of psycho-motor skills. This review explores and discusses the potential applications of 3D printed models and guides, and haptic simulators in the teaching and management of endodontic procedures. An understanding of the pertinent technology related to the production of 3D printed objects and the operation of haptic simulators are also presented.
Quasi-three-dimensional flow solution by meridional plane analysis
NASA Technical Reports Server (NTRS)
Katsanis, T.; Mcnally, W. D.
1974-01-01
A computer program has been developed to obtain subsonic or shockfree transonic, nonviscous flow analysis on the hub-shroud mid-channel flow surface of a turbomachine. The analysis may be for any annular passage, with or without blades. The blades may be fixed or rotating and may be twisted and leaned. The flow may be axial, radial or mixed. Blade surface velocities over the entire blade are approximated based on the rate of change of angular momentum. This gives a 3-D flow picture based on a 2-D analysis. The paper discusses the method used for the program and shows examples of the type of passages and blade rows which can be analyzed. Also, some numerical examples are given to show how the program can be used for practical assistance in design of blading, annular passages, and annular diffusers.
48 CFR 27.201-2 - Contract clauses.
Code of Federal Regulations, 2010 CFR
2010-10-01
... all R&D solicitations and contracts for which the primary purpose is R&D work, except that this... exclusively for R&D work. (3) Use the clause with its Alternate II in solicitations and contracts for... schedule set by a regulatory body. (b) Insert the clause at 52.227-2, Notice and Assistance Regarding...
Structure and ligand-based design of P-glycoprotein inhibitors: a historical perspective.
Palmeira, Andreia; Sousa, Emilia; Vasconcelos, M Helena; Pinto, Madalena; Fernandes, Miguel X
2012-01-01
Computer-assisted drug design (CADD) is a valuable approach for the discovery of new chemical entities in the field of cancer therapy. There is a pressing need to design and develop new, selective, and safe drugs for the treatment of multidrug resistance (MDR) cancer forms, specifically active against P-glycoprotein (P-gp). Recently, a crystallographic structure for mouse P-gp was obtained. However, for decades the design of new P-gp inhibitors employed mainly ligand-based approaches (SAR, QSAR, 3D-QSAR and pharmacophore studies), and structure-based studies used P-gp homology models. However, some of those results are still the pillars used as a starting point for the design of potential P-gp inhibitors. Here, pharmacophore mapping, (Q)SAR, 3D-QSAR and homology modeling, for the discovery of P-gp inhibitors are reviewed. The importance of these methods for understanding mechanisms of drug resistance at a molecular level, and design P-gp inhibitors drug candidates are discussed. The examples mentioned in the review could provide insights into the wide range of possibilities of using CADD methodologies for the discovery of efficient P-gp inhibitors.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lim, T; Wang, J; Frank, S
Purpose: The current CT-based post-implant dosimetry allows precise seed localization but limited anatomical delineation. Switching to MR-based post-implant dosimetry is confounded by imprecise seed localization. One approach is to place positive-contrast markers (Sirius) adjacent to the negative-contrast seeds. This patient study aims to assess the utility of a 3D fast spoiled gradient-recalled echo (FSPGR) sequence to visualize Sirius markers for post-implant dosimetry. Methods: MRI images were acquired in prostate implant patients (n=10) on Day 0 (day-of-implant) and Day 30. The post-implant MR protocol consisted of 3D T2-weighted fast-spin-echo (FSE), T2-weighted 2D-FSE (axial) and T1-weighted 2D-FSE (axial/sagittal/coronal). We incorporated a 3D-FSPGRmore » sequence into the post-implant MR protocol to visualize the Sirius markers. Patients were scanned with different number-of-excitations (6, 8, 10), field-of-view (10cm, 14cm, 18cm), slice thickness (1mm, 0.8mm), flip angle (14 degrees, 20 degrees), bandwidth (122.070 Hz/pixel, 325.508 Hz/pixel, 390.625 Hz/pixel), phase encoding steps (160, 192, 224, 256), frequency-encoding direction (right/left, anterior/posterior), echo-time type (minimum-full, out-of-phase), field strength (1.5T, 3T), contrast (with, without), scanner vendor (Siemens, GE), coil (endorectal-coil only, endorectal-and-torso-coil, torsocoil only), endorectal-coil filling (30cc, 50cc) and endorectal-coil filling type (air, perfluorocarbon [PFC]). For post-implant dosimetric evaluation with greater anatomical detail, 3D-FSE images were fused with 3D-FSPGR images. For comparison with CT-based post-implant dosimetry, CT images were fused with 3D-FSPGR images. Results: The 3D-FSPGR sequence facilitated visualization of markers in patients. Marker visualization helped distinguish signal voids as seeds versus needle tracks for more definitive MR-based post-implant dosimetry. On the CT-MR fused images, the distance between the seed on CT to MR images was 3.2±1.6mm in patients with no endorectal coil, 2.3±0.8mm in patients with 30cc-PFC-filled endorectal-coil and 5.0±1.8mm in patients with 50cc-PFC-filled endorectal-coil. Conclusion: An MR protocol to visualize positive-contrast Sirius markers to assist in the identification of negative-contrast seeds was demonstrated. S Frank is a co-founder of C4 Imaging LLC, the manufacturer of the MRI markers.« less
Population norms for the EQ-5D-3L: a cross-country analysis of population surveys for 20 countries.
Janssen, M F; Szende, A; Cabases, J; Ramos-Goñi, J M; Vilagut, G; König, H H
2018-02-14
This study provides EQ-5D population norms for 20 countries (N = 163,838), which can be used to compare profiles for patients with specific conditions with data for the average person in the general population in a similar age and/or gender group. Descriptive EQ-5D data are provided for the total population, by gender and by seven age groups. Provided index values are based on European VAS for all countries, based on TTO for 11 countries and based on VAS for 10 countries. Important differences exist in EQ-5D reported health status across countries after standardizing for population structure. Self-reported health according to all five dimensions and EQ VAS generally decreased with increasing age and was lower for females. Mean self-rated EQ VAS scores varied from 70.4 to 83.3 in the total population by country. The prior living standards (GDP per capita) in the countries studied are correlated most with the EQ VAS scores (0.58), while unemployment appeared to be significantly correlated in people over the age of 45 only. A country's expenditure on health care correlated moderately with higher ratings on the EQ VAS (0.55). EQ-5D norms can be used as reference data to assess the burden of disease of patients with specific conditions. Such information, in turn, can inform policy-making and assist in setting priorities in health care.
Hybrid helical magnetic microrobots obtained by 3D template-assisted electrodeposition.
Zeeshan, Muhammad A; Grisch, Roman; Pellicer, Eva; Sivaraman, Kartik M; Peyer, Kathrin E; Sort, Jordi; Özkale, Berna; Sakar, Mahmut S; Nelson, Bradley J; Pané, Salvador
2014-04-09
Hybrid helical magnetic microrobots are achieved by sequential electrodeposition of a CoNi alloy and PPy inside a photoresist template patterned by 3D laser lithography. A controlled actuation of the microrobots by a rotating magnetic field is demonstrated in a fluidic environment. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
ICCE/ICCAI 2000 Full & Short Papers (Virtual Reality in Education).
ERIC Educational Resources Information Center
2000
This document contains the full text of the following full and short papers on virtual reality in education from ICCE/ICCAI 2000 (International Conference on Computers in Education/International Conference on Computer-Assisted Instruction): (1) "A CAL System for Appreciation of 3D Shapes by Surface Development (C3D-SD)" (Stephen C. F. Chan, Andy…
32 CFR Appendix A to Part 555 - Director of Defense Research and Engineering
Code of Federal Regulations, 2013 CFR
2013-07-01
... 32 National Defense 3 2013-07-01 2013-07-01 false Director of Defense Research and Engineering A... Engineering June 14, 1974. Memorandum for Assistant Secretaries of the Military Departments (R&D) Subject: Non... Engineering Assistant Secretary of Defense (Comptroller). Subject: Non-Defense Work in DOD Laboratories and R...
32 CFR Appendix A to Part 555 - Director of Defense Research and Engineering
Code of Federal Regulations, 2010 CFR
2010-07-01
... 32 National Defense 3 2010-07-01 2010-07-01 true Director of Defense Research and Engineering A... Engineering June 14, 1974. Memorandum for Assistant Secretaries of the Military Departments (R&D) Subject: Non... Engineering Assistant Secretary of Defense (Comptroller). Subject: Non-Defense Work in DOD Laboratories and R...
32 CFR Appendix A to Part 555 - Director of Defense Research and Engineering
Code of Federal Regulations, 2014 CFR
2014-07-01
... 32 National Defense 3 2014-07-01 2014-07-01 false Director of Defense Research and Engineering A... Engineering June 14, 1974. Memorandum for Assistant Secretaries of the Military Departments (R&D) Subject: Non... Engineering Assistant Secretary of Defense (Comptroller). Subject: Non-Defense Work in DOD Laboratories and R...
32 CFR Appendix A to Part 555 - Director of Defense Research and Engineering
Code of Federal Regulations, 2011 CFR
2011-07-01
... 32 National Defense 3 2011-07-01 2009-07-01 true Director of Defense Research and Engineering A... Engineering June 14, 1974. Memorandum for Assistant Secretaries of the Military Departments (R&D) Subject: Non... Engineering Assistant Secretary of Defense (Comptroller). Subject: Non-Defense Work in DOD Laboratories and R...
32 CFR Appendix A to Part 555 - Director of Defense Research and Engineering
Code of Federal Regulations, 2012 CFR
2012-07-01
... 32 National Defense 3 2012-07-01 2009-07-01 true Director of Defense Research and Engineering A... Engineering June 14, 1974. Memorandum for Assistant Secretaries of the Military Departments (R&D) Subject: Non... Engineering Assistant Secretary of Defense (Comptroller). Subject: Non-Defense Work in DOD Laboratories and R...
Threshold Tear Strength of Elastomers.
1982-04-01
O 0 0 C~j C-J C7,) 0DY 122 DISTRIBUTION LIST No. Cooes No. Cooies Dr. L.V. Schmidt I Dr. F. Roberto 1 ’Assistant Secretary of the Navy Code AFRPL MKPA...Research Scientific Advisor Directorate of Aerospace Sciences Commandant of the Marine Corps Bolling Air Force Base Code RD-i Washington, D.C. 20332...Directorate of Chemical Sciences Arlington, VA 22217 Bolling Air Force Base Washington, D.C. 20332 Mr. David Siegel D Office of Naval Research Dr. John S
Zheng, Sheng-Nai; Yao, Qing-Qiang; Mao, Feng-Yong; Zheng, Peng-Fei; Tian, Shu-Chang; Li, Jia-Yi; Yu, Yi-Fan; Liu, Shuai; Zhou, Jin; Hu, Jun; Xu, Yan; Tang, Kai; Lou, Yue; Wang, Li-Ming
2017-10-01
The aim of the present study was to investigate the application of 3D printing (3DP) rapid prototyping (RP) technique-assisted percutaneous fixation in the treatment of femoral intertrochanteric fracture (ITF) using proximal femoral nail anti-rotation (PFNA). A total of 39 patients with unstable ITF were included in the current study. Patients were divided into two groups: 19 patients were examined using computed tomography scanning and underwent PFNA with SDP-RP whereas the other 20 patients underwent conventional PFNA treatment. Anatomical data were converted from the Digital Imaging and Communications in Medicine format to the stereolithography format using M3D software. The 3DP-RP model was established using the fused deposition modeling technique and the length and diameter of the main screw blade was measured during the simulation. The postoperative femoral neck-shaft angle (NSA), surgery duration, intraoperative and postoperative blood loss, and the duration of hospital stay were recorded and compared with the corresponding values in conventional surgery. No significant differences were observed in mean PFNA size between the implants used and the preoperative planning estimates. It was demonstrated that the 3DP-RP assisted procedure resulted in more effective reduction of the NSA. Furthermore, patients undergoing 3DP-RP experienced a significant reduction in duration of surgery (P<0.01), as well as reductions in intraoperative (P=0.02) and postoperative (P=0.03) blood loss, compared with conventional surgery. At 6 months post-surgery, no cases of hip varus/vague deformities or implant failure were observed in patients that underwent either the 3DP-RP-assisted or conventional procedure. The results of the present study suggest that the 3DP-RP technique is able to create an accurate model of the ITF, which facilitates surgical planning and fracture reduction, thus improving the efficiency of PFNA surgery for ITFs.
Assisting the visually impaired: obstacle detection and warning system by acoustic feedback.
Rodríguez, Alberto; Yebes, J Javier; Alcantarilla, Pablo F; Bergasa, Luis M; Almazán, Javier; Cela, Andrés
2012-12-17
The aim of this article is focused on the design of an obstacle detection system for assisting visually impaired people. A dense disparity map is computed from the images of a stereo camera carried by the user. By using the dense disparity map, potential obstacles can be detected in 3D in indoor and outdoor scenarios. A ground plane estimation algorithm based on RANSAC plus filtering techniques allows the robust detection of the ground in every frame. A polar grid representation is proposed to account for the potential obstacles in the scene. The design is completed with acoustic feedback to assist visually impaired users while approaching obstacles. Beep sounds with different frequencies and repetitions inform the user about the presence of obstacles. Audio bone conducting technology is employed to play these sounds without interrupting the visually impaired user from hearing other important sounds from its local environment. A user study participated by four visually impaired volunteers supports the proposed system.
Super-resolved microsphere-assisted Mirau digital holography by oblique illumination
NASA Astrophysics Data System (ADS)
Abbasian, Vahid; Ganjkhani, Yasaman; Akhlaghi, Ehsan A.; Anand, Arun; Javidi, Bahram; Moradi, Ali-Reza
2018-06-01
In this paper, oblique illumination is used to improve the lateral resolution and edge sharpness in microsphere (MS)-assisted Mirau digital holographic microscopy (Mirau-DHM). Abbe showed that tilting the illumination light allows entrance of higher spatial frequencies into the imaging system thus increasing the resolution power. We extended the idea to common-path DHM, based on Mirau objective, toward super-resolved 3D imaging. High magnification Mirau objectives are very expensive and low-magnification ones suffer from low resolution, therefore, any attempt to increase the effective resolution of the system may be of a great interest. We have already demonstrated the effective resolution increasing of a Mirau-DHM system by incorporating a transparent MS within the working distance of the objective. Here, we show that by integrating a MS-assisted Mirau-DHM with the oblique illumination even higher resolutions can be achieved. We have applied the technique for various samples and have shown the increase in the lateral resolution for the both cases of Mirau-DHM with and without the MS.
Assisting the Visually Impaired: Obstacle Detection and Warning System by Acoustic Feedback
Rodríguez, Alberto; Yebes, J. Javier; Alcantarilla, Pablo F.; Bergasa, Luis M.; Almazán, Javier; Cela, Andrés
2012-01-01
The aim of this article is focused on the design of an obstacle detection system for assisting visually impaired people. A dense disparity map is computed from the images of a stereo camera carried by the user. By using the dense disparity map, potential obstacles can be detected in 3D in indoor and outdoor scenarios. A ground plane estimation algorithm based on RANSAC plus filtering techniques allows the robust detection of the ground in every frame. A polar grid representation is proposed to account for the potential obstacles in the scene. The design is completed with acoustic feedback to assist visually impaired users while approaching obstacles. Beep sounds with different frequencies and repetitions inform the user about the presence of obstacles. Audio bone conducting technology is employed to play these sounds without interrupting the visually impaired user from hearing other important sounds from its local environment. A user study participated by four visually impaired volunteers supports the proposed system. PMID:23247413
ABS 3D printed solutions for cryogenic applications
NASA Astrophysics Data System (ADS)
Bartolomé, E.; Bozzo, B.; Sevilla, P.; Martínez-Pasarell, O.; Puig, T.; Granados, X.
2017-03-01
3D printing has become a common, inexpensive and rapid prototyping technique, enabling the ad hoc fabrication of complex shapes. In this paper, we demonstrate that 3D printed objects in ABS can be used at cryogenic temperatures, offering flexible solutions in different fields. Firstly, a thermo-mechanical characterization of ABS 3D printed specimens at 77 K is reported, which allowed us to delimit the type of cryogenic uses where 3D printed pieces may be implemented. Secondly, we present three different examples where ABS 3D printed objects working at low temperatures have provided specific solutions: (i) SQUID inserts for angular magnetometry (low temperature material characterization field); (ii) a cage support for a metamaterial ;magnetic concentrator; (superconductivity application), and (iii) dedicated tools for cryopreservation in assisted reproductive techniques (medicine field).
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zhang, Wen; Wong, Ping Kwan Johnny; Zhang, Dong
Quasi-1D nanochains of spherical magnetic ferrite particles with a homogeneous particle size of ≈200 nm and a micrometer-sized chain length are fabricated in this paper via a self-assembly method under an external magnetic field. This assisting magnetic field (H assist), applied during synthesis, significantly modifies the distribution of the Fe 2+O h, Fe 3+T d, and Fe 3+O h cations in the chains, as demonstrated by X-ray magnetic circular dichroism (XMCD) combined with theoretical analysis. This provides direct evidence of the nontrivial role of external synthetic conditions for defining the crystal chemistry of nanoscale ferrites and in turn their magneticmore » properties, providing an extra degree of freedom for intentional control over the performances of 1D magnetic nanodevices for various applications. Magnetic imaging, performed via XMCD in photoemission electron microscopy, further shows the possibility of creating and trapping a series of adjacent magnetic domain walls in a single chain, suggesting that there is great application potential for these nanochains in 1D magnetic nanodevices, as determined by field- or current-driven domain wall motions. Finally, practical control over the magnetic properties of the nanochains is also achieved by extrinsic dopants of cobalt and zinc, which are observed to occupy the ferrite ionic sites in a selective manner.« less
Zhang, Wen; Wong, Ping Kwan Johnny; Zhang, Dong; ...
2017-05-30
Quasi-1D nanochains of spherical magnetic ferrite particles with a homogeneous particle size of ≈200 nm and a micrometer-sized chain length are fabricated in this paper via a self-assembly method under an external magnetic field. This assisting magnetic field (H assist), applied during synthesis, significantly modifies the distribution of the Fe 2+O h, Fe 3+T d, and Fe 3+O h cations in the chains, as demonstrated by X-ray magnetic circular dichroism (XMCD) combined with theoretical analysis. This provides direct evidence of the nontrivial role of external synthetic conditions for defining the crystal chemistry of nanoscale ferrites and in turn their magneticmore » properties, providing an extra degree of freedom for intentional control over the performances of 1D magnetic nanodevices for various applications. Magnetic imaging, performed via XMCD in photoemission electron microscopy, further shows the possibility of creating and trapping a series of adjacent magnetic domain walls in a single chain, suggesting that there is great application potential for these nanochains in 1D magnetic nanodevices, as determined by field- or current-driven domain wall motions. Finally, practical control over the magnetic properties of the nanochains is also achieved by extrinsic dopants of cobalt and zinc, which are observed to occupy the ferrite ionic sites in a selective manner.« less
Lattice engineering through nanoparticle–DNA frameworks
Tian, Ye; Zhang, Yugang; Wang, Tong; ...
2016-02-22
Advances in self-assembly over the past decade have demonstrated that nano- and microscale particles can be organized into a large diversity of ordered three-dimensional (3D) lattices. However, the ability to generate different desired lattice types from the same set of particles remains challenging. Here, we show that nanoparticles can be assembled into crystalline and open 3D frameworks by connecting them through designed DNA-based polyhedral frames. The geometrical shapes of the frames, combined with the DNA-assisted binding properties of their vertices, facilitate the well-defined topological connections between particles in accordance with frame geometry. With this strategy, different crystallographic lattices using themore » same particles can be assembled by introduction of the corresponding DNA polyhedral frames. As a result, this approach should facilitate the rational assembly of nanoscale lattices through the design of the unit cell.« less
Making physiology learning memorable: a mobile phone-assisted case-based instructional strategy.
Kukolja Taradi, S; Taradi, M
2016-09-01
The goal of the present study was to determine whether an active learning/teaching strategy facilitated with mobile technologies can improve students' levels of memory retention of key physiological concepts. We used a quasiexperimental pretest/posttest nonequivalent group design to compare the test performances of second-year medical students (n = 311) taught by conventional didactic methods (traditional group) with those involved in a case-based problem-solving learning approach facilitated with mobile phones as web-based "clickers" (experimental group). Using their cell phones, students answered the same questions about the key physiological concepts three times. A pretest to determine their baseline knowledge was followed by two followup tests after 1 wk and 2 mo, respectively. The experimental group scored a mean of 93.2% correct items after 1 wk and 84.8% correct items after 2 mo [95% confidence intervals: (89.4, 97.0) and (79.4, 90.3), respectively]. Compared with their colleagues in the traditional group who scored 33.3% [95% confidence interval: (18.9, 47.8)] and 38.5% [95% confidence interval: (23.6, 53.4)] correct items, respectively, this was a significant increase of ∼50% (P < 0.0001). Furthermore, for the experimental group, Cohen's effect size (d) values of d = 1.67 (1-wk posttest) and d = 1.38 (2-mo posttest) suggested a very high practical significance. In contrast, in the traditional group, Cohen's d values of d = 0.04 (1-wk posttest) and d = 0.15 (2-mo posttest) assumed a very low practical significance. Copyright © 2016 The American Physiological Society.
3D-WOVEN FIBER-REINFORCED COMPOSITE FOR CAD/CAM DENTAL APPLICATION
Petersen, Richard; Liu, Perng-Ru
2016-01-01
Three-dimensional (3D)-woven noncrimp fiber-reinforced composite (FRC) was tested for mechanical properties in the two principal directions of the main XY plane and compared to different Computer-Aided-Design/Computer-Aided-Machining (CAD/CAM) Dental Materials. The Dental Materials included ceramic with Vitablock Mark II®, ProCAD®, InCeram® Spinel, InCeram® Alumina and InCeram® Zirconia in addition to a resin-based 3M Corp. Paradigm® particulate-filled composite. Alternate material controls included Coors 300 Alumina Ceramic and a tungsten carbide 22% cobalt cermet. The 3D-woven FRC was vacuum assisted resin transfer molding processed as a one-depth-thickness ~19-mm preform with a vinyl-ester resin and cut into blocks similar to the commercial CAD/CAM Dental Materials. Mechanical test samples prepared for a flexural three-point span length of 10.0 mm were sectioned for minimum-depth cuts to compare machinability and fracture resistance between groups. 3D-woven FRC improved mechanical properties with significant statistical differences over all CAD/CAM Dental Materials and Coors Alumina Ceramic for flexural strength (p<0.001), resilience (p<0.05), work of fracture (p<0.001), strain energy release (p<0.05), critical stress intensity factor (p<0.001) and strain (p<0.001). PMID:27642198
Depth assisted compression of full parallax light fields
NASA Astrophysics Data System (ADS)
Graziosi, Danillo B.; Alpaslan, Zahir Y.; El-Ghoroury, Hussein S.
2015-03-01
Full parallax light field displays require high pixel density and huge amounts of data. Compression is a necessary tool used by 3D display systems to cope with the high bandwidth requirements. One of the formats adopted by MPEG for 3D video coding standards is the use of multiple views with associated depth maps. Depth maps enable the coding of a reduced number of views, and are used by compression and synthesis software to reconstruct the light field. However, most of the developed coding and synthesis tools target linearly arranged cameras with small baselines. Here we propose to use the 3D video coding format for full parallax light field coding. We introduce a view selection method inspired by plenoptic sampling followed by transform-based view coding and view synthesis prediction to code residual views. We determine the minimal requirements for view sub-sampling and present the rate-distortion performance of our proposal. We also compare our method with established video compression techniques, such as H.264/AVC, H.264/MVC, and the new 3D video coding algorithm, 3DV-ATM. Our results show that our method not only has an improved rate-distortion performance, it also preserves the structure of the perceived light fields better.
3D-WOVEN FIBER-REINFORCED COMPOSITE FOR CAD/CAM DENTAL APPLICATION.
Petersen, Richard; Liu, Perng-Ru
2016-05-01
Three-dimensional (3D)-woven noncrimp fiber-reinforced composite (FRC) was tested for mechanical properties in the two principal directions of the main XY plane and compared to different Computer-Aided-Design/Computer-Aided-Machining (CAD/CAM) Dental Materials. The Dental Materials included ceramic with Vitablock Mark II®, ProCAD®, InCeram® Spinel, InCeram® Alumina and InCeram® Zirconia in addition to a resin-based 3M Corp. Paradigm® particulate-filled composite. Alternate material controls included Coors 300 Alumina Ceramic and a tungsten carbide 22% cobalt cermet. The 3D-woven FRC was vacuum assisted resin transfer molding processed as a one-depth-thickness ~19-mm preform with a vinyl-ester resin and cut into blocks similar to the commercial CAD/CAM Dental Materials. Mechanical test samples prepared for a flexural three-point span length of 10.0 mm were sectioned for minimum-depth cuts to compare machinability and fracture resistance between groups. 3D-woven FRC improved mechanical properties with significant statistical differences over all CAD/CAM Dental Materials and Coors Alumina Ceramic for flexural strength (p<0.001), resilience (p<0.05), work of fracture (p<0.001), strain energy release (p<0.05), critical stress intensity factor (p<0.001) and strain (p<0.001).
NASA Astrophysics Data System (ADS)
Groch, A.; Seitel, A.; Hempel, S.; Speidel, S.; Engelbrecht, R.; Penne, J.; Höller, K.; Röhl, S.; Yung, K.; Bodenstedt, S.; Pflaum, F.; dos Santos, T. R.; Mersmann, S.; Meinzer, H.-P.; Hornegger, J.; Maier-Hein, L.
2011-03-01
One of the main challenges related to computer-assisted laparoscopic surgery is the accurate registration of pre-operative planning images with patient's anatomy. One popular approach for achieving this involves intraoperative 3D reconstruction of the target organ's surface with methods based on multiple view geometry. The latter, however, require robust and fast algorithms for establishing correspondences between multiple images of the same scene. Recently, the first endoscope based on Time-of-Flight (ToF) camera technique was introduced. It generates dense range images with high update rates by continuously measuring the run-time of intensity modulated light. While this approach yielded promising results in initial experiments, the endoscopic ToF camera has not yet been evaluated in the context of related work. The aim of this paper was therefore to compare its performance with different state-of-the-art surface reconstruction methods on identical objects. For this purpose, surface data from a set of porcine organs as well as organ phantoms was acquired with four different cameras: a novel Time-of-Flight (ToF) endoscope, a standard ToF camera, a stereoscope, and a High Definition Television (HDTV) endoscope. The resulting reconstructed partial organ surfaces were then compared to corresponding ground truth shapes extracted from computed tomography (CT) data using a set of local and global distance metrics. The evaluation suggests that the ToF technique has high potential as means for intraoperative endoscopic surface registration.
NASA Astrophysics Data System (ADS)
Mailfert, Julien; Van de Kerkhove, Jeroen; De Bisschop, Peter; De Meyer, Kristin
2014-03-01
A Metal1-layer (M1) patterning study is conducted on 20nm node (N20) for random-logic applications. We quantified the printability performance on our test vehicle for N20, corresponding to Poly/M1 pitches of 90/64nm, and with a selected minimum M1 gap size of 70nm. The Metal1 layer is patterned with 193nm immersion lithography (193i) using Negative Tone Developer (NTD) resist, and a double-patterning Litho-Etch-Litho-Etch (LELE) process. Our study is based on Logic test blocks that we OPCed with a combination of calibrated models for litho and for etch. We report the Overlapping Process Window (OPW), based on a selection of test structures measured after-etch. We find that most of the OPW limiting structures are EOL (End-of-Line) configurations. Further analysis of these individual OPW limiters will reveal that they belong to different types, such as Resist 3D (R3D) and Mask 3D (M3D) sensitive structures, limiters related to OPC (Optical Proximity Corrections) options such as assist placement, or the choice of CD metrics and tolerances for calculation of the process windows itself. To guide this investigation, we will consider a `reference OPC' case to be compared with other solutions. In addition, rigorous simulations and OPC verifications will complete the after-etch measurements to help us to validate our experimental findings.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Racine, E; Hautvast, G; Binnekamp, D
Purpose: To report on the results of a complete permanent implant brachytherapy procedure assisted by an electromagnetic (EM) hollow needle possessing both 3D tracking and seed drop detection abilities. Methods: End-to-end in-phantom EM-assisted LDR procedures were conducted. The novel system consisted of an EM tracking apparatus (NDI Aurora V2, Planar Field Generator), a 3D US scanner (Philips CX50), a hollow needle prototype allowing 3D tracking and seed drop detection and a specially designed treatment planning software (Philips Healthcare). A tungsten-doped 30 cc spherical agarose prostate immersed in gelatin was used for the treatment. A cylindrical shape of 0.8 cc wasmore » carved along its diameter to mimic the urethra. An initial plan of 26 needles and 47 seeds was established with the system. The plan was delivered with the EM-tracked hollow needle, and individual seed drop locations were recorded on the fly. The phantom was subsequently imaged with a CT scanner from which seed positions and contour definitions were obtained. The DVHs were then independently recomputed and compared with those produced by the planning system, both before and after the treatment. Results: Of the 47 seeds, 45 (96%) were detected by the EM technology embedded in the hollow needle design. The executed plan (from CT analysis) differed from the initial plan by 2%, 14% and 8% respectively in terms of V100, D90 and V150 for the prostate, and by 8%, 7% and 10% respectively in terms of D5, V100 and V120 for the urethra. Conclusion: The average DVH deviations between initial and executed plans were within a 5% tolerance imposed for this proof-of-concept assessment. This relatively good concordance demonstrates the feasibility and potential benefits of combining EM tracking and seed drop detection for real-time dosimetry validation and assistance in permanent implant brachytherapy procedures. This project has been entirely funded by Philips Healthcare.« less
Danti, Serena; Ciofani, Gianni; Pertici, Gianni; Moscato, Stefania; D'Alessandro, Delfo; Ciabatti, Elena; Chiellini, Federica; D'Acunto, Mario; Mattoli, Virgilio; Berrettini, Stefano
2015-07-01
In this communication, we introduce boron nitride nanotube (BNNT)-functionalised muscle cell/microfibre mesh constructs, obtained via tissue engineering, as a three-dimensional (3D) platform to study a wireless stimulation system for electrically responsive cells and tissues. Our stimulation strategy exploits the piezoelectric behaviour of some classes of ceramic nanoparticles, such as BNNTs, able to polarize under mechanical stress, e.g. using low-frequency ultrasound (US). In the microfibre scaffolds, C2C12 myoblasts were able to differentiate into viable myotubes and to internalize BNNTs, also upon US irradiation, so as to obtain a nanotech-assisted 3D in vitro model. We then tested our stimulatory system on 2D and 3D cellular models by investigating the expression of connexin 43 (Cx43), as a molecule involved in cell crosstalk and mechanotransduction, and myosin, as a myogenic differentiation marker. Cx43 gene expression revealed a marked model dependency. In control samples (without US and/or BNNTs), Cx43 was upregulated under 2D culture conditions (10.78 ± 1.05-fold difference). Interactions with BNNTs increased Cx43 expression in 3D samples. Cx43 mRNA dropped in 2D under the 'BNNTs + US' regimen, while it was best enhanced in 3D samples (3.58 ± 1.05 vs 13.74 ± 1.42-fold difference, p = 0.0001). At the protein level, the maximal expressions of Cx43 and myosin were detected in the 3D model. In contrast with the 3D model, in 2D cultures, BNNTs and US exerted a synergistic depletive effect upon myosin synthesis. These findings indicate that model dimensionality and stimulatory regimens can strongly affect the responses of signalling and differentiation molecules, proving the importance of developing proper in vitro platforms for biological modelling. Copyright © 2014 John Wiley & Sons, Ltd.
NASA Astrophysics Data System (ADS)
Amurisana, Bao.; Zhiqiang, Song.; Haschaolu, O.; Yi, Chen; Tegus, O.
2018-02-01
3D hierarchical GdPO4·H2O:Ln3+ (Ln3+ = Eu3+, Ce3+, Tb3+) flower clusters were successfully prepared on glass slide substrate by a simple, economical hydrothermal process with the assistance of disodium ethylenediaminetetraacetic acid (Na2H2L, where L4- = (CH2COO)2N(CH2)2N(CH2COO)24-). In this process, Na2H2L was used as both a chelating agent and a structure-director. The hierarchical flower clusters have an average diameter of 7-12 μm and are composed of well-aligned microrods. The influence of the molar ratio of Na2H2L/Gd3+ and reaction time on the morphology was systematically studied. A possible crystal growth and formation mechanism of hierarchical flower clusters is proposed based on the evolution of morphology as a function of reaction time. The self-assembled GdPO4·H2O:Ln3+ superstructures exhibit strong orange-red (Eu3+, 5D0 → 7F1), green (Tb3+, 5D4 → 7F5) and near ultraviolet emissions (Ce3+, 5d → 7F5/2) under ultraviolet excitation, respectively. This study may provide a new channel for building hierarchically superstructued oxide micro/nanomaterials with optical and new properties.
Bagan, Patrick; De Dominicis, Florence; Hernigou, Jacques; Dakhil, Bassel; Zaimi, Rym; Pricopi, Ciprian; Le Pimpec Barthes, Françoise; Berna, Pascal
2015-06-01
Common video systems for video-assisted thoracic surgery (VATS) provide the surgeon a two-dimensional (2D) image. This study aimed to evaluate performances of a new three-dimensional high definition (3D-HD) system in comparison with a two-dimensional high definition (2D-HD) system when conducting a complete thoracoscopic lobectomy (CTL). This multi-institutional comparative study trialled two video systems: 2D-HD and 3D-HD video systems used to conduct the same type of CTL. The inclusion criteria were T1N0M0 non-small-cell lung carcinoma (NSCLC) in the left lower lobe and suitable for thoracoscopic resection. The CTL was performed by the same surgeon using either a 3D-HD or 2D-HD system. Eighteen patients with NSCLC were included in the study between January and December 2013: 14 males, 4 females, with a median age of 65.6 years (range: 49-81). The patients were randomized before inclusion into two groups: to undergo surgery with the use of a 2D-HD or 3D-HD system. We compared operating time, the drainage duration, hospital stay and the N upstaging rate from the definitive histology. The use of the 3D-HD system significantly reduced the surgical time (by 17%). However, chest-tube drainage, hospital stay, the number of lymph-node stations and upstaging were similar in both groups. The main finding was that 3D-HD system significantly reduced the surgical time needed to complete the lobectomy. Thus, future integration of 3D-HD systems should improve thoracoscopic surgery, and enable more complex resections to be performed. It will also help advance the field of endoscopically assisted surgery. © The Author 2015. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.
A comparative analysis and guide to virtual reality robotic surgical simulators.
Julian, Danielle; Tanaka, Alyssa; Mattingly, Patricia; Truong, Mireille; Perez, Manuela; Smith, Roger
2018-02-01
Since the US Food and Drug Administration approved robotically assisted surgical devices for human surgery in 2000, the number of surgeries utilizing this innovative technology has risen. In 2015, approximately 650 000 robot-assisted procedures were performed worldwide. Surgeons must be properly trained to safely transition to using such innovative technology. Multiple virtual reality robotic simulators are now commercially available for educational and training purposes. There is a need for comparative evaluations of these simulators to aid users in selecting an appropriate device for their purposes. We conducted a comparison of the design and capabilities of all dedicated simulators of the da Vinci robot - the da Vinci Skills Simulator (dVSS), dV-Trainer (dVT), Robotic Skills Simulators (RoSS) and the RobotiX Mentor. This paper provides the base specifications of the hardware and software, with an emphasis on the training capabilities of each system. Each simulator contains a large number of training exercises for skills development: dVSS n = 40, dVT n = 65, RoSS n = 52, RobotiX Mentor n = 31. All four offer 3D visual images but use different display technologies. The dVSS leverages the real robotic surgical console to provide visualization, hand controls and foot pedals. The dVT, RoSS and RobotiX Mentor created simulated versions of all of these control systems. Each includes systems management services that allow instructors to collect, export and analyze the scores of students using the simulators. This study provides comparative information on the four simulators' functional capabilities. Each device offers unique advantages and capabilities for training robotic surgeons. Each has been the subject of validation experiments, which have been published in the literature. But those do not provide specific details on the capabilities of the simulators, which are necessary for an understanding sufficient to select the one best suited for an organization's needs. This article provides comparative information to assist with that type of selection. Copyright © 2017 John Wiley & Sons, Ltd.
Liu, Wei; Xu, Qun
2018-04-20
Localized surface plasmon resonances (LSPRs) of ultra-thin two-dimensional (2D) nanomaterials opened a new regime in plasmonics in the last several years. 2D plasmonic materials are yet concentrated on the crystal structure, amorphous materials are hardly reported because of their limited preparation methods rather than undesired plasmonic properties. Taking molybdenum oxides as an example, herein, we elaborate the 2D amorphous plasmons prepared with the assistance of supercritical CO2. In brief, we examine the reported characteristic plasmonic properties of molybdenum oxides, and applications of supercritical CO2 in formations of 2D layer materials as well as introduced phase and disorder engineering based on our researchs. Furthermore, we propose our perspective on the development of 2D plasmons, especially for amorphous layer materials in the future. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
TMSOTf assisted synthesis of 2'-deoxy-2'-[18F]fluoro-β-D-arabinofuranosylcytosine ([18F]FAC).
Gangangari, Kishore K; Humm, John L; Larson, Steven M; Pillarsetty, Naga Vara Kishore
2018-01-01
[18F]FAC (2'-deoxy-2'-[18F]fluoro-β-D-arabinofuranosylcytosine, 1) is a versatile probe for imaging deoxycytidine kinase (dCK) expression levels in vivo. dCK is responsible for phosphorylation of deoxycytidine (dC, 2) and other nucleoside analogs, plays a key role in immune activation and has demonstrated to be one of the key enzymes in activating nucleoside based drugs including gemcitabine. Reported synthesis of [18F]FAC is high yielding but is quite challenging requiring bromination using HBr and careful drying of excess HBr which is critical for successful synthesis. Here in we report a simplified trimethylsilyl trifluoromethanesulfonate (TMSOTf) assisted synthesis of [18F]FAC eliminating the need of bromination and drying. [18F]FAC (β-anomer) was synthesized with average isolated decay corrected yield of 10.59 + 4.2% (n = 6) with radiochemical purity of >98% and total synthesis time of 158 + 19 min.
Zhang, Xiang; Shi, Chunsheng; Liu, Enzuo; Li, Jiajun; Zhao, Naiqin; He, Chunnian
2015-10-28
In this study, we demonstrated nitrogen-doped graphene network supported few-layered graphene shell encapsulated Cu nanoparticles (NPs) (Cu@G-NGNs) as a sensing platform, which were constructed by a simple and scalable in situ chemical vapor deposition (CVD) technique with the assistance of a self-assembled three-dimensional (3D) NaCl template. Compared with pure Cu NPs and graphene decorated Cu NPs, the graphene shells can strengthen the plasmonic coupling between graphene and Cu, thereby contributing to an obvious improvement in the local electromagnetic field that was validated by finite element numerical simulations, while the 3D nitrogen-doped graphene walls with a large surface area facilitated molecule adsorption and the doped nitrogen atoms embedded in the graphene lattice can reduce the surface energy of the system. With these merits, a good surface enhanced Raman spectroscopy (SERS) activity of the 3D Cu@G-NGN painting film on glass was demonstrated using rhodamine 6G and crystal violet as model analytes, exhibiting a satisfactory sensitivity, reproducibility and stability. As far as we know, this is the first report on the in situ synthesis of nitrogen-doped graphene/copper nanocomposites and this facile and low-cost Cu-based strategy tends to be a good supplement to Ag and Au based substrates for SERS applications.
NASA Astrophysics Data System (ADS)
Chaisaowong, Kraisorn; Jiang, Mingze; Faltin, Peter; Merhof, Dorit; Eisenhawer, Christian; Gube, Monika; Kraus, Thomas
2016-03-01
Pleural thickenings are caused by asbestos exposure and may evolve into malignant pleural mesothelioma. An early diagnosis plays a key role towards an early treatment and an increased survival rate. Today, pleural thickenings are detected by visual inspection of CT data, which is time-consuming and underlies the physician's subjective judgment. A computer-assisted diagnosis system to automatically assess pleural thickenings has been developed, which includes not only a quantitative assessment with respect to size and location, but also enhances this information with an anatomical description, i.e. lung side (left, right), part of pleura (pars costalis, mediastinalis, diaphragmatica, spinalis), as well as vertical (upper, middle, lower) and horizontal (ventral, dorsal) position. For this purpose, a 3D anatomical model of the lung surface has been manually constructed as a 3D atlas. Three registration sub-steps including rigid, affine, and nonrigid registration align the input patient lung to the 3D anatomical atlas model of the lung surface. Finally, each detected pleural thickening is assigned a set of labels describing its anatomical properties. Through this added information, an enhancement to the existing computer-assisted diagnosis system is presented in order to assure a higher precision and reproducible assessment of pleural thickenings, aiming at the diagnosis of the pleural mesothelioma in its early stage.
Wei, Lang; Yao, Jiannian; Fu, Hongbing
2013-09-24
The size, shape, and crystallinity of organic nanostructures play an important role in their physical properties and are mainly determined by the self-assembling kinetics of molecular components often involving the solvent conditions. Here, we reported a kinetically controlled self-assembly of C60 assisted by the solvent carbon bisulfide (CS2) into single-crystal ultrathin microribbons of 2C60·3CS2, upon mixing the poor solvent isopropyl alcohol with a C60/CS2 stock solution. Surface energy calculations reveal that these microribbons represent a kinetically favored high-energy state as compared with the thermodynamically stable shape of prismatic rods. High-resolution transmission electron microscopy observations clarify that association of CS2 at the nucleation stage helps to guide and rigidify the formation of π-π stacking 1D chains of C60 through the surrounding CS2 cage-like structures, which further act as glue, boosting lateral assembly of as-formed 1D chains into untrathin 2D microribbon single crystals. Precise control over the thickness, width, and length of 2C60·3CS2 microribbons was achieved by manipulation of the growth kinetics through adjusting the solvent conditions. Upon heating to 120 °C, sublimation of CS2 components results in fcc C60 microribbons. We found that both microribbons of solvated monoclinic 2C60·3CS2 and pure fcc C60 exhibit highly sensitive photoconductivity properties with a spectral response range covering UV to visible. The highest on/off ratio of two-terminal photodetectors based on single ribbons reaches around 250, while the responsitivity is about 75.3 A W(-1) in the UV region and 90.4 A W(-1) in the visible region.
Suzuki, Hideaki; Yu, Jiwen; Wang, Fei; Zhang, Jinfa
2013-06-01
Cytoplasmic male sterility (CMS), which is a maternally inherited trait and controlled by novel chimeric genes in the mitochondrial genome, plays a pivotal role in the production of hybrid seed. In cotton, no PCR-based marker has been developed to discriminate CMS-D8 (from Gossypium trilobum) from its normal Upland cotton (AD1, Gossypium hirsutum) cytoplasm. The objective of the current study was to develop PCR-based single nucleotide polymorphic (SNP) markers from mitochondrial genes for the CMS-D8 cytoplasm. DNA sequence variation in mitochondrial genes involved in the oxidative phosphorylation chain including ATP synthase subunit 1, 4, 6, 8 and 9, and cytochrome c oxidase 1, 2 and 3 subunits were identified by comparing CMS-D8, its isogenic maintainer and restorer lines on the same nuclear genetic background. An allelic specific PCR (AS-PCR) was utilized for SNP typing by incorporating artificial mismatched nucleotides into the third or fourth base from the 3' terminus in both the specific and nonspecific primers. The result indicated that the method modifying allele-specific primers was successful in obtaining eight SNP markers out of eight SNPs using eight primer pairs to discriminate two alleles between AD1 and CMS-D8 cytoplasms. Two of the SNPs for atp1 and cox1 could also be used in combination to discriminate between CMS-D8 and CMS-D2 cytoplasms. Additionally, a PCR-based marker from a nine nucleotide insertion-deletion (InDel) sequence (AATTGTTTT) at the 59-67 bp positions from the start codon of atp6, which is present in the CMS and restorer lines with the D8 cytoplasm but absent in the maintainer line with the AD1 cytoplasm, was also developed. A SNP marker for two nucleotide substitutions (AA in AD1 cytoplasm to CT in CMS-D8 cytoplasm) in the intron (1,506 bp) of cox2 gene was also developed. These PCR-based SNP markers should be useful in discriminating CMS-D8 and AD1 cytoplasms, or those with CMS-D2 cytoplasm as a rapid, simple, inexpensive, and reliable genotyping tool to assist hybrid cotton breeding.
3D tracking of laparoscopic instruments using statistical and geometric modeling.
Wolf, Rémi; Duchateau, Josselin; Cinquin, Philippe; Voros, Sandrine
2011-01-01
During a laparoscopic surgery, the endoscope can be manipulated by an assistant or a robot. Several teams have worked on the tracking of surgical instruments, based on methods ranging from the development of specific devices to image processing methods. We propose to exploit the instruments' insertion points, which are fixed on the patients abdominal cavity, as a geometric constraint for the localization of the instruments. A simple geometric model of a laparoscopic instrument is described, as well as a parametrization that exploits a spherical geometric grid, which offers attracting homogeneity and isotropy properties. The general architecture of our proposed approach is based on the probabilistic Condensation algorithm.
Developing and Testing a 3d Cadastral Data Model a Case Study in Australia
NASA Astrophysics Data System (ADS)
Aien, A.; Kalantari, M.; Rajabifard, A.; Williamson, I. P.; Shojaei, D.
2012-07-01
Population growth, urbanization and industrialization place more pressure on land use with the need for increased space. To extend the use and functionality of the land, complex infrastructures are being built, both vertically and horizontally, layered and stacked. These three-dimensional (3D) developments affect the interests (Rights, Restrictions, and Responsibilities (RRRs)) attached to the underlying land. A 3D cadastre will assist in managing the effects of 3D development on a particular extent of land. There are many elements that contribute to developing a 3D cadastre, such as existing of 3D property legislations, 3D DBMS, 3D visualization. However, data modelling is one of the most important elements of a successful 3D cadastre. As architectural models of houses and high rise buildings help their users visualize the final product, 3D cadastre data model supports 3D cadastre users to understand the structure or behavior of the system and has a template that guides them to construct and implement the 3D cadastre. Many jurisdictions, organizations and software developers have built their own cadastral data model. Land Administration Domain Model (DIS-ISO 19152, The Netherlands) and ePlan (Intergovernmental Committee on Surveying and Mapping, Australia) are examples of existing data models. The variation between these data models is the result of different attitudes towards cadastres. However, there is a basic common thread among them all. Current cadastral data models use a 2D land-parcel concept and extend it to support 3D requirements. These data models cannot adequately manage and represent the spatial extent of 3D RRRs. Most of the current cadastral data models have been influenced by a very broad understanding of 3D cadastral concepts because better clarity in what needs to be represented and analysed in the cadastre needs to be established. This paper presents the first version of a 3D Cadastral Data Model (3DCDM_Version 1.0). 3DCDM models both the legal and physical extent of 3D properties and associated interests. The data model extends the traditional cadastral requirements to cover other applications such as urban planning and land valuation and taxation. A demonstration of a test system on the proposed data model is also presented. The test is based on a case study in Victoria, Australia to evaluate the effectiveness of the data model.
ERIC Educational Resources Information Center
Porter, Lon A., Jr.; Chapman, Cole A.; Alaniz, Jacob A.
2017-01-01
In this work, a versatile and user-friendly selection of stereolithography (STL) files and computer-aided design (CAD) models are shared to assist educators and students in the production of simple and inexpensive 3D printed filter fluorometer instruments. These devices are effective resources for supporting active learners in the exploration of…
DOE Office of Scientific and Technical Information (OSTI.GOV)
Du Haijuan; Zunzhe Shu; Niu Yunyin, E-mail: niuyy@zzu.edu.cn
2012-06-15
Abstrct: Four novel organic-inorganic hybrid materials based on Mo-POMs and organic templates, namely [DEB] [{beta}-Mo{sub 8}O{sub 26}] [NH{sub 4}]{sub 2} (1), [BMIM] [{beta}-Mo{sub 8}O{sub 26}]{sub 0.5}{center_dot}H{sub 2}O (2), [BMIM] [1D-Mo{sub 8}O{sub 26}]{sub 0.5} (3) and {l_brace}3D-[Cu(DIE){sub 2}] [1D-Mo{sub 8}O{sub 26}]{sub 0.5}{r_brace}{sub {infinity}} (4) [DEB= 1,1 Prime -diethyl-4,4 Prime -bipyridinium, BMIM=1,1 Prime -bis(1-methylimidazolium)methylene, DIE=1,2-diimidazoloethane] have been hydrothermally synthesized and characterized by elemental analyses, IR spectroscopy, thermal gravimetric analysis(TGA) and single-crystal X-ray diffraction. Both compounds 1 and 2 are POMs-based supramolecular compounds consisted of independent [{beta}-Mo{sub 8}O{sub 26}]{sup 4-} anions and [DEB]{sup 2+} or [BMIM]{sup 2+} organic cations. Compound 3 is themore » first external template example of Mo-POMs-based supramolecular network incorporated with novel {sup 1}/{sub {infinity}}[{beta}-Mo{sub 8}O{sub 26}]{sup 4-} polymeric chains. Compound 4 is a rare supramolecular structure that contains octamolybdate {sup 1}/{sub {infinity}}[{beta}-Mo{sub 8}O{sub 26}]{sup 4-} polymeric chains interconnected via DIE ligands to form a 3D net. Moreover, it was indicated that these polyacid compounds had definite catalytic activities on the probe reaction of acetaldehyde oxidation to acetic acid with H{sub 2}O{sub 2}. - Graphical abstract: Four novel organic templated polyoxometalates comprising of 0D, 1D and 3D supramolecular frameworks together with the catalytic activities on the acetaldehyde oxidation to acetic acid were reported. Highlights: Using cation templated self-assembly four novel polyoxometalates were prepared. Compounds 1 and 2 consisted of independent [{beta}-Mo{sub 8}O{sub 26}]{sup 4-} anions and organic cations. Compound 3 is the first external template-assisted POMs with {sup 1}/{sub {infinity}}[{beta}-Mo{sub 8}O{sub 26}]{sup 4-} chain. Compound 4 is a rare 3D net containing {sup 1}/{sub {infinity}}[{beta}-Mo{sub 8}O{sub 26}]{sup 4-} 1D chain and DIE ligands. These compounds had definite catalytic activities on the acetaldehyde oxidation.« less
24 CFR 578.37 - Program components and uses of assistance.
Code of Federal Regulations, 2013 CFR
2013-04-01
...-term (up to 3 months) and/or medium-term (for 3 to 24 months) tenant-based rental assistance, as set... providing short-term and/or medium-term rental assistance to program participants, the rental assistance is... ensuring long-term housing stability. The project is exempt from this requirement if the Violence Against...
24 CFR 578.37 - Program components and uses of assistance.
Code of Federal Regulations, 2014 CFR
2014-04-01
...-term (up to 3 months) and/or medium-term (for 3 to 24 months) tenant-based rental assistance, as set... providing short-term and/or medium-term rental assistance to program participants, the rental assistance is... ensuring long-term housing stability. The project is exempt from this requirement if the Violence Against...
Whitcomb, Mary Beth; Doval, John; Peters, Jason
2011-01-01
Ultrasonography has gained increased utility to diagnose pelvic fractures in horses; however, internal pelvic contours can be difficult to appreciate from external palpable landmarks. We developed three-dimensional (3D) simulations of the pelvic ultrasonographic examination to assist with translation of pelvic contours into two-dimensional (2D) images. Contiguous 1mm transverse computed tomography (CT) images were acquired through an equine femur and hemipelvis using a single slice helical scanner. 3D surface models were created using a DICOM reader and imported into a 3D modeling and animation program. The bone models were combined with a purchased 3D horse model and the skin made translucent to visualize pelvic surface contours. 3D models of ultrasound transducers were made from reference photos, and a thin sector shape was created to depict the ultrasound beam. Ultrasonographic examinations were simulated by moving transducers on the skin surface and rectally to produce images of pelvic structures. Camera angles were manipulated to best illustrate the transducer-beam-bone interface. Fractures were created in multiple configurations. Animations were exported as QuickTime movie files for use in presentations coupled with corresponding ultrasound videoclips. 3D models provide a link between ultrasonographic technique and image generation by depicting the interaction of the transducer, ultrasound beam, and structure of interest. The horse model was important to facilitate understanding of the location of pelvic structures relative to the skin surface. While CT acquisition time was brief, manipulation within the 3D software program was time intensive. Results were worthwhile from an instructional standpoint based on user feedback. © 2011 Veterinary Radiology & Ultrasound.
Kajiwara, Naohiro; Patrick Barron, James; Kato, Yasufumi; Kakihana, Masatoshi; Ohira, Tatsuo; Kawate, Norihiko; Ikeda, Norihiko
2015-01-01
Medical economics have significant impact on the entire country. The explosion in surgical techniques has been accompanied by questions regarding actual improvements in outcome and cost-effectiveness, such as the da Vinci(®) Surgical System (dVS) compared with conventional video-assisted thoracic surgery (VATS). To establish a medical fee system for robot-assisted thoracic surgery (RATS), which is a system not yet firmly established in Japan. This study examines the cost benefit performance (CBP) based on medical fees compared with VATS and RATS under the Japanese National Health Insurance System (JNHIS) introduced in 2012. The projected (but as yet undecided) price in the JNHIS would be insufficient if institutions have less than even 200 dVS cases per year. Only institutions which perform more than 300 dVS operations per year would obtain a positive CBP with the projected JNHIS reimbursement. Thus, under the present conditions, it is necessary to perform at least 300 dVS operations per year in each institution with a dVS system to avoid financial deficit with current robotic surgical management. This may hopefully encourage a downward price revision of the dVS equipment by the manufacture which would result in a decrease in the cost per procedure.
Hamm, Julian; Atwal, Anita
2017-01-01
Background In the field of occupational therapy, the assistive equipment provision process (AEPP) is a prominent preventive strategy used to promote independent living and to identify and alleviate fall risk factors via the provision of assistive equipment within the home environment. Current practice involves the use of paper-based forms that include 2D measurement guidance diagrams that aim to communicate the precise points and dimensions that must be measured in order to make AEPP assessments. There are, however, issues such as “poor fit” of equipment due to inaccurate measurements taken and recorded, resulting in more than 50% of equipment installed within the home being abandoned by patients. This paper presents a novel 3D measurement aid prototype (3D-MAP) that provides enhanced measurement and assessment guidance to patients via the use of 3D visualization technologies. Objective The purpose of this study was to explore the perceptions of older adults with regard to the barriers and opportunities of using the 3D-MAP application as a tool that enables patient self-delivery of the AEPP. Methods Thirty-three community-dwelling older adults participated in interactive sessions with a bespoke 3D-MAP application utilizing the retrospective think-aloud protocol and semistructured focus group discussions. The system usability scale (SUS) questionnaire was used to evaluate the application’s usability. Thematic template analysis was carried out on the SUS item discussions, think-aloud, and semistructured focus group data. Results The quantitative SUS results revealed that the application may be described as having “marginal-high” and “good” levels of usability, along with strong agreement with items relating to the usability (P=.004) and learnability (P<.001) of the application. Four high-level themes emerged from think-aloud and focus groups discussions: (1) perceived usefulness (PU), (2) perceived ease of use (PEOU), (3) application use (AU) and (4) self-assessment (SA). The application was seen as a useful tool to enhance visualization of measurement guidance and also to promote independent living, ownership of care, and potentially reduce waiting times. Several design and functionality recommendations emerged from the study, such as a need to manipulate the view and position of the 3D furniture models, and a need for clearer visual prompts and alternative keyboard interface for measurement entry. Conclusions Participants perceived the 3D-MAP application as a useful tool that has the potential to make significant improvements to the AEPP, not only in terms of accuracy of measurement, but also by potentially enabling older adult patients to carry out the data collection element of the AEPP themselves. Further research is needed to further adapt the 3D-MAP application in line with the study outcomes and to establish its clinical utility with regards to effectiveness, efficiency, accuracy, and reliability of measurements that are recorded using the application and to compare it with 2D measurement guidance leaflets. PMID:28630034
Wang, Xue-Dong; Wang, Hong-Guang; Shi, Jun; Duan, Wei-Dong; Luo, Ying; Ji, Wen-Bin; Zhang, Ning; Dong, Jia-Hong
2017-06-01
Decision making and surgical planning are to achieve the precise balance of maximal removal of target lesion, maximal sparing of functional liver remnant volume, and minimal surgical invasiveness and therefore, crucial in liver surgery. The aim of this prospective study was to validate the accuracy and predictability of 3D interactive quantitative surgical planning approach (IQSP), and to evaluate the impact of IQSP on traditional surgical plans based on 2D images. A total of 305 consecutive patients undergoing hepatectomy were included in this study. Surgical plans were created by traditional 2D approach using picture archiving and communication system (PACS) and 3D approach using IQSP respectively by two groups of physicians who did not know the surgical plans of the other group. The two surgical plans were submitted to the chief surgeon for selection before operation. The specimens were weighed. The two surgical plans were compared and analyzed retrospectively based on the operation results. The two surgical plans were successfully developed in all 305 patients and all the 3D IQSP surgical plans were selected as the final decision. Total 278 patients successfully underwent surgery, including 147 uncomplex hepatectomy and 131 complex hepatectomy. Twenty-seven patients were withdrawn from hepatectomy. In the uncomplex group, the two surgical plans were the same in all 147 patients and no statistically significant difference was found among 2D calculated resection volume (2D-RV), 3D IQSP calculated resection volume (IQSP-RV) and the specimen volume. In the complex group, the two surgical plans were different in 49 patients (49/131, 37.4%). According to the significance of differences, the 49 different patients were classified into three grades. No statistically significant difference was found between IQSP-RV and specimen volume. The coincidence rate of territory analysis of IQSP with operation was 92.1% (93/101) for 101 patients of anatomic hepatectomy. The accuracy and predictability of 3D IQSP were validated. Compared with traditional surgical planning, 3D IQSP can provide more quantitative information of anatomic structure. With the assistance of 3D IQSP, traditional surgical plans were modified to be more radical and safe.
Neurosurgical robotic arm drilling navigation system.
Lin, Chung-Chih; Lin, Hsin-Cheng; Lee, Wen-Yo; Lee, Shih-Tseng; Wu, Chieh-Tsai
2017-09-01
The aim of this work was to develop a neurosurgical robotic arm drilling navigation system that provides assistance throughout the complete bone drilling process. The system comprised neurosurgical robotic arm navigation combining robotic and surgical navigation, 3D medical imaging based surgical planning that could identify lesion location and plan the surgical path on 3D images, and automatic bone drilling control that would stop drilling when the bone was to be drilled-through. Three kinds of experiment were designed. The average positioning error deduced from 3D images of the robotic arm was 0.502 ± 0.069 mm. The correlation between automatically and manually planned paths was 0.975. The average distance error between automatically planned paths and risky zones was 0.279 ± 0.401 mm. The drilling auto-stopping algorithm had 0.00% unstopped cases (26.32% in control group 1) and 70.53% non-drilled-through cases (8.42% and 4.21% in control groups 1 and 2). The system may be useful for neurosurgical robotic arm drilling navigation. Copyright © 2016 John Wiley & Sons, Ltd.
Pre-operative segmentation of neck CT datasets for the planning of neck dissections
NASA Astrophysics Data System (ADS)
Cordes, Jeanette; Dornheim, Jana; Preim, Bernhard; Hertel, Ilka; Strauss, Gero
2006-03-01
For the pre-operative segmentation of CT neck datasets, we developed the software assistant NeckVision. The relevant anatomical structures for neck dissection planning can be segmented and the resulting patient-specific 3D-models are visualized afterwards in another software system for intervention planning. As a first step, we examined the appropriateness of elementary segmentation techniques based on gray values and contour information to extract the structures in the neck region from CT data. Region growing, interactive watershed transformation and live-wire are employed for segmentation of different target structures. It is also examined, which of the segmentation tasks can be automated. Based on this analysis, the software assistant NeckVision was developed to optimally support the workflow of image analysis for clinicians. The usability of NeckVision was tested within a first evaluation with four otorhinolaryngologists from the university hospital of Leipzig, four computer scientists from the university of Magdeburg and two laymen in both fields.
NASA Astrophysics Data System (ADS)
Yu, Yang; Zeng, Zheng
2009-10-01
By discussing the causes behind the high amendments ratio in the implementation of urban regulatory detailed plans in China despite its law-ensured status, the study aims to reconcile conflict between the legal authority of regulatory detailed planning and the insufficient scientific support in its decision-making and compilation by introducing into the process spatial analysis based on GIS technology and 3D modeling thus present a more scientific and flexible approach to regulatory detailed planning in China. The study first points out that the current compilation process of urban regulatory detailed plan in China employs mainly an empirical approach which renders it constantly subjected to amendments; the study then discusses the need and current utilization of GIS in the Chinese system and proposes the framework of a GIS-assisted 3D spatial analysis process from the designer's perspective which can be regarded as an alternating processes between the descriptive codes and physical design in the compilation of regulatory detailed planning. With a case study of the processes and results from the application of the framework, the paper concludes that the proposed framework can be an effective instrument which provides more rationality, flexibility and thus more efficiency to the compilation and decision-making process of urban regulatory detailed plan in China.
Spring assisted cranioplasty: A patient specific computational model.
Borghi, Alessandro; Rodriguez-Florez, Naiara; Rodgers, Will; James, Gregory; Hayward, Richard; Dunaway, David; Jeelani, Owase; Schievano, Silvia
2018-03-01
Implantation of spring-like distractors in the treatment of sagittal craniosynostosis is a novel technique that has proven functionally and aesthetically effective in correcting skull deformities; however, final shape outcomes remain moderately unpredictable due to an incomplete understanding of the skull-distractor interaction. The aim of this study was to create a patient specific computational model of spring assisted cranioplasty (SAC) that can help predict the individual overall final head shape. Pre-operative computed tomography images of a SAC patient were processed to extract a 3D model of the infant skull anatomy and simulate spring implantation. The distractors were modeled based on mechanical experimental data. Viscoelastic bone properties from the literature were tuned using the specific patient procedural information recorded during surgery and from x-ray measurements at follow-up. The model accurately captured spring expansion on-table (within 9% of the measured values), as well as at first and second follow-ups (within 8% of the measured values). Comparison between immediate post-operative 3D head scanning and numerical results for this patient proved that the model could successfully predict the final overall head shape. This preliminary work showed the potential application of computational modeling to study SAC, to support pre-operative planning and guide novel distractor design. Copyright © 2018 IPEM. Published by Elsevier Ltd. All rights reserved.
Bagley, James R; Galpin, Andrew J
2015-01-01
Interdisciplinary exploration is vital to education in the 21st century. This manuscript outlines an innovative laboratory-based teaching method that combines elements of biochemistry/molecular biology, kinesiology/health science, computer science, and manufacturing engineering to give students the ability to better conceptualize complex biological systems. Here, we utilize technology available at most universities to print three-dimensional (3D) scale models of actual human muscle cells (myofibers) out of bioplastic materials. The same methodological approach could be applied to nearly any cell type or molecular structure. This advancement is significant because historically, two-dimensional (2D) myocellular images have proven insufficient for detailed analysis of organelle organization and morphology. 3D imaging fills this void by providing accurate and quantifiable myofiber structural data. Manipulating tangible 3D models combats 2D limitation and gives students new perspectives and alternative learning experiences that may assist their understanding. This approach also exposes learners to 1) human muscle cell extraction and isolation, 2) targeted fluorescence labeling, 3) confocal microscopy, 4) image processing (via open-source software), and 5) 3D printing bioplastic scale-models (×500 larger than the actual cells). Creating these physical models may further student's interest in the invisible world of molecular and cellular biology. Furthermore, this interdisciplinary laboratory project gives instructors of all biological disciplines a new teaching tool to foster integrative thinking. © 2015 The International Union of Biochemistry and Molecular Biology.
Sensor supported pilot assistance for helicopter flight in DVE
NASA Astrophysics Data System (ADS)
Waanders, Tim; Münsterer, T.; Kress, M.
2013-05-01
Helicopter operations at low altitude are to this day only performed under VFR conditions in which safe piloting of the aircraft relies on the pilot's visual perception of the outside environment. However, there are situations in which a deterioration of visibility conditions may cause the pilot to lose important visual cues thereby increasing workload and compromising flight safety and mission effectiveness. This paper reports on a pilot assistance system for all phases of flight which is intended to: • Provide navigational support and mission management • Support landings/take-offs in unknown environment and in DVE • Enhance situational awareness in DVE • Provide obstacle and terrain surface detection and warning • Provide upload, sensor based update and download of database information for debriefing and later missions. The system comprises a digital terrain and obstacle database, tactical information, flight plan management combined with an active 3D sensor enabling the above mentioned functionalities. To support pilots during operations in DVE, an intuitive 3D/2D cueing through both head-up and head-down means is proposed to retain situational awareness. This paper further describes the system concept and will elaborate on results of simulator trials in which the functionality was evaluated by operational pilots in realistic and demanding scenarios such as a SAR mission to be performed in mountainous area under different visual conditions. The objective of the simulator trials was to evaluate the functional integration and HMI definition for the NH90 Tactical Transport Helicopter.
Gu, X Y; Chen, X B; Jiao, T; Zhang, F Q; Jiang, X Q
2017-06-09
Objective: To explore a digital negative molds technique based on three-dimensional (3D) printing to assist in the manufacture of maxillofacial prostheses, and to improve the deficiency of the current clinical treatment. Methods: Seventeen patients with maxillofacial defects (including nasal defects, orbital defects, cheek defects, auricle defect) were scanned by means of facial optical scanning and computer tomography (CT). The 3D models were then reconstructed and global registration was made to merge the reconstructed models into a new digital model for 3D design. The 3D design of the prostheses was implemented in software. The mechanical connection structure was designed by forward engineering technology for 3 patients with intra-oral defects in maxilla who needed to make removable partial dentures, so that the silicone prostheses and removable partial denture could be combined. The removable partial dentures were made by conventional method and connected with the prostheses. According to the 3D data of the prostheses, the digital negative molds were designed, and the 3D printing technology was used to finish the processing of the resin molds. Silicone for prostheses were filled and cured in the resin molds to fabricate the clinical restorations for the patients. The margin adaptation and retention of the prostheses was detected. Results: Twenty patients with varying degrees of maxillofacial defects were rehabilitated using the courses developed in the study. All patients reported no pain or discomfort during the treatment; and they were satisfied with the final prostheses of the shape, color, retention, stability, etc. Eighteen of the prostheses showed good marginal adaptation, and sixteen of the prostheses showed good retention effect. Conclusions: The digital negative molds technique used in this study could greatly reduce the intensity of manual operation and provided a good therapeutic effect for patients with maxillofacial defects.
O'Brien, Travis J; LeLacheur, Susan; Ward, Caitlin; Lee, Norman H; Callier, Shawneequa; Harralson, Arthur F
2016-03-01
We assessed the impact of personal CYP2D6 testing on physician assistant student competency in, and attitudes toward, pharmacogenetics (PGx). Buccal samples were genotyped for CYP2D6 polymorphisms. Results were discussed during a 3-h PGx workshop. PGx knowledge was assessed by pre- and post-tests. Focus groups assessed the impact of the workshop on attitudes toward the clinical utility of PGx. Both student knowledge of PGx, and its perceived clinical utility, increased immediately following the workshop. However, exposure to PGx on clinical rotations following the workshop seemed to influence student attitudes toward PGx utility. Personal CYP2D6 testing improves both knowledge and comfort with PGx. Continued exposure to PGx concepts is important for transfer of learning.
Luites, J W H; Wymenga, A B; Blankevoort, L; Kooloos, J M G; Verdonschot, N
2011-01-01
Femoral graft placement is an important factor in the success of anterior cruciate ligament (ACL) reconstruction. In addition to improving the accuracy of femoral tunnel placement, Computer Assisted Surgery (CAS) can be used to determine the anatomic location. This is achieved by using a 3D femoral template which indicates the position of the anatomical ACL center based on endoscopically measurable landmarks. This study describes the development and application of this method. The template is generated through statistical shape analysis of the ACL insertion, with respect to the anteromedial (AM) and posterolateral (PL) bundles. The ligament insertion data, together with the osteocartilage edge on the lateral notch, were mapped onto a cylinder fitted to the intercondylar notch surface (n = 33). Anatomic variation, in terms of standard variation of the positions of the ligament centers in the template, was within 2.2 mm. The resulting template was programmed in a computer-assisted navigation system for ACL replacement and its accuracy and precision were determined on 31 femora. It was found that with the navigation system the AM and PL tunnels could be positioned with an accuracy of 2.5 mm relative to the anatomic insertion centers; the precision was 2.4 mm. This system consists of a template that can easily be implemented in 3D computer navigation software. Requiring no preoperative images and planning, the system provides adequate accuracy and precision to position the entrance of the femoral tunnels for anatomical single- or double-bundle ACL reconstruction.
Verdijk, Noortje A; Kasteleyn, Marise J; Harmans, Lara M; Talboom, Irvin JSH; Numans, Mattijs E; Chavannes, Niels H
2017-01-01
Background Worldwide, nearly 3 million people die of chronic obstructive pulmonary disease (COPD) every year. Integrated disease management (IDM) improves disease-specific quality of life and exercise capacity for people with COPD, but can also reduce hospital admissions and hospital days. Self-management of COPD through eHealth interventions has shown to be an effective method to improve the quality and efficiency of IDM in several settings, but it remains unknown which factors influence usage of eHealth and change in behavior of patients. Objective Our study, e-Vita COPD, compares different levels of integration of Web-based self-management platforms in IDM in three primary care settings. The main aim of this study is to analyze the factors that successfully promote the use of a self-management platform for COPD patients. Methods The e-Vita COPD study compares three different approaches to incorporating eHealth via Web-based self-management platforms into IDM of COPD using a parallel cohort design. Three groups integrated the platforms to different levels. In groups 1 (high integration) and 2 (medium integration), randomization was performed to two levels of personal assistance for patients (high and low assistance); in group 3 there was no integration into disease management (none integration). Every visit to the e-Vita and Zorgdraad COPD Web platforms was tracked objectively by collecting log data (sessions and services). At the first log-in, patients completed a baseline questionnaire. Baseline characteristics were automatically extracted from the log files including age, gender, education level, scores on the Clinical COPD Questionnaire (CCQ), dyspnea scale (MRC), and quality of life questionnaire (EQ5D). To predict the use of the platforms, multiple linear regression analyses for the different independent variables were performed: integration in IDM (high, medium, none), personal assistance for the participants (high vs low), educational level, and self-efficacy level (General Self-Efficacy Scale [GSES]). All analyses were adjusted for age and gender. Results Of the 702 invited COPD patients, 215 (30.6%) registered to a platform. Of the 82 patients in group 1 (high integration IDM), 36 were in group 1A (personal assistance) and 46 in group 1B (low assistance). Of the 96 patients in group 2 (medium integration IDM), 44 were in group 2A (telephone assistance) and 52 in group 2B (low assistance). A total of 37 patients participated in group 3 (no integration IDM). In all, 107 users (49.8%) visited the platform at least once in the 15-month period. The mean number of sessions differed between the three groups (group 1: mean 10.5, SD 1.3; group 2: mean 8.8, SD 1.4; group 3: mean 3.7, SD 1.8; P=.01). The mean number of sessions differed between the high-assistance and low-assistance groups in groups 1 and 2 (high: mean 11.8, SD 1.3; low: mean 6.7, SD 1.4; F1,80=6.55, P=.01). High-assistance participants used more services (mean 45.4, SD 6.2) than low-assistance participants (mean 21.2, SD 6.8; F1,80=6.82, P=.01). No association was found between educational level and usage and between GSES and usage. Conclusions Use of a self-management platform is higher when participants receive adequate personal assistance about how to use the platform. Blended care, where digital health and usual care are integrated, will likely lead to increased use of the online program. Future research should provide additional insights into the preferences of different patient groups. Trial Registration Nederlands Trial Register NTR4098; http://www.trialregister.nl/trialreg/admin/rctview.asp?TC=4098 (Archived by WebCite at http://www.webcitation.org/6qO1hqiJ1) PMID:28566268
Code of Federal Regulations, 2013 CFR
2013-04-01
... 23 Highways 1 2013-04-01 2013-04-01 false Policy. 656.3 Section 656.3 Highways FEDERAL HIGHWAY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION ENGINEERING AND TRAFFIC OPERATIONS CARPOOL AND VANPOOL PROJECTS § 656.3 Policy. Section 126(d) of the Surface Transportation Assistance Act of 1978 declares that...
Code of Federal Regulations, 2012 CFR
2012-04-01
... 23 Highways 1 2012-04-01 2012-04-01 false Policy. 656.3 Section 656.3 Highways FEDERAL HIGHWAY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION ENGINEERING AND TRAFFIC OPERATIONS CARPOOL AND VANPOOL PROJECTS § 656.3 Policy. Section 126(d) of the Surface Transportation Assistance Act of 1978 declares that...
Code of Federal Regulations, 2014 CFR
2014-04-01
... 23 Highways 1 2014-04-01 2014-04-01 false Policy. 656.3 Section 656.3 Highways FEDERAL HIGHWAY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION ENGINEERING AND TRAFFIC OPERATIONS CARPOOL AND VANPOOL PROJECTS § 656.3 Policy. Section 126(d) of the Surface Transportation Assistance Act of 1978 declares that...
Code of Federal Regulations, 2010 CFR
2010-04-01
... 23 Highways 1 2010-04-01 2010-04-01 false Policy. 656.3 Section 656.3 Highways FEDERAL HIGHWAY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION ENGINEERING AND TRAFFIC OPERATIONS CARPOOL AND VANPOOL PROJECTS § 656.3 Policy. Section 126(d) of the Surface Transportation Assistance Act of 1978 declares that...
Code of Federal Regulations, 2011 CFR
2011-04-01
... 23 Highways 1 2011-04-01 2011-04-01 false Policy. 656.3 Section 656.3 Highways FEDERAL HIGHWAY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION ENGINEERING AND TRAFFIC OPERATIONS CARPOOL AND VANPOOL PROJECTS § 656.3 Policy. Section 126(d) of the Surface Transportation Assistance Act of 1978 declares that...
Zheng, Wenhao; Tao, Zhenyu; Lou, Yiting; Feng, Zhenhua; Li, Hang; Cheng, Liang; Zhang, Hui; Wang, Jianshun; Guo, Xiaoshan; Chen, Hua
2017-09-19
This study was aimed to compare conventional surgery and surgery assisted by 3D printing technology in the treatment of calcaneal fractures. In addition, we also investigated the effect of 3D printing technology on the communication between doctors and patients. we enrolled 75 patients with calcaneal fracture from April 2014 to August 2016. They were divided randomly into two groups: 35 cases of 3D printing group, 40 cases of conventional group. The individual models were used to simulate the surgical procedures and carry out the surgery according to plan in 3D printing group. Operation duration, blood loss volume during the surgery, number of intraoperative fluoroscopy and fracture union time were recorded. The radiographic outcomes Böhler angle, Gissane angle, calcaneal width and calcaneal height and final functional outcomes including VAS and AOFAS score as well as the complications were also evaluated. Besides, we made a simple questionnaire to verify the effectiveness of the 3D-printed model for both doctors and patients. The operation duration, blood loss volume and number of intraoperative fluoroscopy for 3D printing group was 71.4 ± 6.8 minutes, 226.1 ± 22.6 ml and 5.6 ± 1.9 times, and for conventional group was 91.3 ± 11.2 minutes, 288.7 ± 34.8 ml and 8.6 ± 2.7 times respectively. There was statistically significant difference between the conventional group and 3D printing group (p < 0.05). Additionally, 3D printing group achieved significantly better radiographic results than conventional group both postoperatively and at the final follow-up (p < 0.05). However, No significant difference was noted in the final functional outcomes between the two groups. As for complications, there was no significant difference between the two groups. Furthermore, the questionnaire showed that both doctors and patients exhibited high scores of overall satisfaction with the use of a 3D printing model. This study suggested the clinical feasibility of 3D printing technology in treatment of calcaneal fractures.
Baez, E; Huber, A; Vetter, M; Hackelöer, B-J
2003-03-01
The aim of this study was to evaluate the use of three-dimensional (3D) ultrasonography in the complete excision of benign breast tumors using ultrasound-guided vacuum-assisted core-needle biopsy (Mammotome). A protocol for the management of benign breast tumors is proposed. Twenty consecutive patients with sonographically benign breast lesions underwent 3D ultrasound-guided mammotome biopsy under local anesthesia. The indication for surgical biopsy was a solid lesion with benign characteristics on both two-dimensional (2D) and 3D ultrasound imaging, increasing in size over time or causing pain or irritation. Preoperatively, the size of the lesion was assessed using 2D and 3D volumetry. During vacuum biopsy the needle was visualized sonographically in all three dimensions, including the coronal plane. Excisional biopsy was considered complete when no residual tumor tissue could be seen sonographically. Ultrasonographic follow-up examinations were performed on the following day and 3-6 months later to assess residual tissue and scarring. All lesions were histologically benign. Follow-up examinations revealed complete excision of all lesions of < 1.5 mL in volume as assessed by 3D volumetry. 3D ultrasonographic volume assessment was more accurate than 2D using the ellipsoid formula or assessment of the maximum diameter for the prediction of complete excision of the tumor. No bleeding or infections occurred postoperatively and no scarring was seen ultrasonographically on follow-up examinations. Ultrasound-guided vacuum-assisted biopsy allows complete excision of benign breast lesions that are =1.5 mL in volume (calculated by 3D volumetry), and thus avoids open surgery and postoperative scarring. Under local anesthesia it is a safe procedure with optimal compliance. 3D ultrasound offers the advantage of better preoperative demonstration of the lesions' margins, resulting in better assessment of volumetry, improved intraoperative needle location and perioperative identification of residual tumor tissue. 3D sonographically guided biopsy should be integrated into breast cancer screening programs as a safe therapeutic option for breast lesions presumed to be benign. Copyright 2003 ISUOG. Published by John Wiley & Sons, Ltd.
Code of Federal Regulations, 2012 CFR
2012-01-01
... 7 Agriculture 13 2012-01-01 2012-01-01 false Amendment to Technical and Supervisory Assistance Grant Agreement D Exhibit D to Subpart K of Part 1944 Agriculture Regulations of the Department of... Technical and Supervisory Assistance Grants Pt. 1944, Subpt. K, Exh. D Exhibit D to Subpart K of Part 1944...
Code of Federal Regulations, 2013 CFR
2013-01-01
... 7 Agriculture 13 2013-01-01 2013-01-01 false Amendment to Technical and Supervisory Assistance Grant Agreement D Exhibit D to Subpart K of Part 1944 Agriculture Regulations of the Department of... Technical and Supervisory Assistance Grants Pt. 1944, Subpt. K, Exh. D Exhibit D to Subpart K of Part 1944...
Code of Federal Regulations, 2014 CFR
2014-01-01
... 7 Agriculture 13 2014-01-01 2013-01-01 true Amendment to Technical and Supervisory Assistance Grant Agreement D Exhibit D to Subpart K of Part 1944 Agriculture Regulations of the Department of... Technical and Supervisory Assistance Grants Pt. 1944, Subpt. K, Exh. D Exhibit D to Subpart K of Part 1944...
Code of Federal Regulations, 2011 CFR
2011-01-01
... 7 Agriculture 13 2011-01-01 2009-01-01 true Amendment to Technical and Supervisory Assistance Grant Agreement D Exhibit D to Subpart K of Part 1944 Agriculture Regulations of the Department of... Technical and Supervisory Assistance Grants Pt. 1944, Subpt. K, Exh. D Exhibit D to Subpart K of Part 1944...
Code of Federal Regulations, 2010 CFR
2010-01-01
... 7 Agriculture 13 2010-01-01 2009-01-01 true Amendment to Technical and Supervisory Assistance Grant Agreement D Exhibit D to Subpart K of Part 1944 Agriculture Regulations of the Department of... Technical and Supervisory Assistance Grants Pt. 1944, Subpt. K, Exh. D Exhibit D to Subpart K of Part 1944...
Zhou, Peng; Wang, Na; Ma, Yang
2018-01-01
The weak photon absorption and high recombination rate of electron-hole pairs in disordered zinc oxide nanowires (ZNWs) limit its application in UV photodetection. This limitation can be overcome by introducing graphene sheets to the ZNWs. Herein we report a high-performance photodetector based on one-dimensional (1D) wide band-gap semiconductor disordered ZNWs composited with reduced graphene oxide (RGO) for ultraviolet (UV) photoresponse enhancement. The RGO/ZNWs composites have been successfully synthetized through UV-assisted photochemical reduction of GO in ZNWs suspension. The material characterizations in morphology, Raman scattering, and Ultraviolet-visible light absorption verified the formation of graphene sheets attached in ZNWs network and the enhancement of UV absorption due to the introduction of graphene. In comparison with photodetectors based on pure ZNWs, the photodetectors based on RGO/ZNWs composite exhibit enhanced photoresponse with photocurrent density of 5.87 mA·cm−2, on/off current ratio of 3.01 × 104, and responsivity of 1.83 A·W−1 when a UV irradiation of 3.26 mW·cm−2 and 1.0 V bias were used. Theory analysis is also presented to get insight into the inherent mechanisms of separation and transportation of photo-excited carriers in RGO/ZNWs composite. PMID:29303994
Chen, Changsong; Zhou, Peng; Wang, Na; Ma, Yang; San, Haisheng
2018-01-05
The weak photon absorption and high recombination rate of electron-hole pairs in disordered zinc oxide nanowires (ZNWs) limit its application in UV photodetection. This limitation can be overcome by introducing graphene sheets to the ZNWs. Herein we report a high-performance photodetector based on one-dimensional (1D) wide band-gap semiconductor disordered ZNWs composited with reduced graphene oxide (RGO) for ultraviolet (UV) photoresponse enhancement. The RGO/ZNWs composites have been successfully synthetized through UV-assisted photochemical reduction of GO in ZNWs suspension. The material characterizations in morphology, Raman scattering, and Ultraviolet-visible light absorption verified the formation of graphene sheets attached in ZNWs network and the enhancement of UV absorption due to the introduction of graphene. In comparison with photodetectors based on pure ZNWs, the photodetectors based on RGO/ZNWs composite exhibit enhanced photoresponse with photocurrent density of 5.87 mA·cm -2 , on/off current ratio of 3.01 × 10⁴, and responsivity of 1.83 A·W -1 when a UV irradiation of 3.26 mW·cm -2 and 1.0 V bias were used. Theory analysis is also presented to get insight into the inherent mechanisms of separation and transportation of photo-excited carriers in RGO/ZNWs composite.
Crossingham, Jodi L; Jenkinson, Jodie; Woolridge, Nick; Gallinger, Steven; Tait, Gordon A; Moulton, Carol-Anne E
2009-01-01
Background: Given the increasing number of indications for liver surgery and the growing complexity of operations, many trainees in surgical, imaging and related subspecialties require a good working knowledge of the complex intrahepatic anatomy. Computed tomography (CT), the most commonly used liver imaging modality, enhances our understanding of liver anatomy, but comprises a two-dimensional (2D) representation of a complex 3D organ. It is challenging for trainees to acquire the necessary skills for converting these 2D images into 3D mental reconstructions because learning opportunities are limited and internal hepatic anatomy is complicated, asymmetrical and variable. We have created a website that uses interactive 3D models of the liver to assist trainees in understanding the complex spatial anatomy of the liver and to help them create a 3D mental interpretation of this anatomy when viewing CT scans. Methods: Computed tomography scans were imported into DICOM imaging software (OsiriX™) to obtain 3D surface renderings of the liver and its internal structures. Using these 3D renderings as a reference, 3D models of the liver surface and the intrahepatic structures, portal veins, hepatic veins, hepatic arteries and the biliary system were created using 3D modelling software (Cinema 4D™). Results: Using current best practices for creating multimedia tools, a unique, freely available, online learning resource has been developed, entitled Visual Interactive Resource for Teaching, Understanding And Learning Liver Anatomy (VIRTUAL Liver) (http://pie.med.utoronto.ca/VLiver). This website uses interactive 3D models to provide trainees with a constructive resource for learning common liver anatomy and liver segmentation, and facilitates the development of the skills required to mentally reconstruct a 3D version of this anatomy from 2D CT scans. Discussion: Although the intended audience for VIRTUAL Liver consists of residents in various medical and surgical specialties, the website will also be useful for other health care professionals (i.e. radiologists, nurses, hepatologists, radiation oncologists, family doctors) and educators because it provides a comprehensive resource for teaching liver anatomy. PMID:19816618
Diffractive optical devices produced by light-assisted trapping of nanoparticles.
Muñoz-Martínez, J F; Jubera, M; Matarrubia, J; García-Cabañes, A; Agulló-López, F; Carrascosa, M
2016-01-15
One- and two-dimensional diffractive optical devices have been fabricated by light-assisted trapping and patterning of nanoparticles. The method is based on the dielectrophoretic forces appearing in the vicinity of a photovoltaic crystal, such as Fe:LiNbO3, during or after illumination. By illumination with the appropriate light distribution, the nanoparticles are organized along patterns designed at will. One- and two-dimensional diffractive components have been achieved on X- and Z-cut Fe:LiNbO3 crystals, with their polar axes parallel and perpendicular to the crystal surface, respectively. Diffraction gratings with periods down to around a few micrometers have been produced using metal (Al, Ag) nanoparticles with radii in the range of 70-100 nm. Moreover, several 2D devices, such as Fresnel zone plates, have been also produced showing the potential of the method. The diffractive particle patterns remain stable when light is removed. A method to transfer the diffractive patterns to other nonphotovoltaic substrates, such as silica glass, has been also reported.
MBE Growth of InN/GaN(0001) and Shape Transitions of InN islands
NASA Astrophysics Data System (ADS)
Cao, Yongge; Xie, Maohai; Liu, Ying; Ng, Y. F.
2003-03-01
Plasma-assisted molecular-beam epitaxial growth of InN on GaN(0001) is investigated. Both layer-by-layer and Stranski-Krastanov (SK) growth modes are observed under different growth windows. Strain relaxation is studied by real-time recording of the in-plane lattice spacing evolutions on RHEED pattern, which suggest a gradual relaxation of the strain in InN film commenced during the first bilayer (BL) deposition and almost completed after 2-4 BLs. For SK growth, 3D islanding initiates after the strain has mostly been relieved, presumably by dislocations. Based on statistical analysis, the shape transitions of 3D islands are firstly observed in the III-nitrides system. The InN islands transform gradually from pyramids to platelets with increasing of In flux. Under In-rich growth condition, the reverse trend of island shape evolution dependence on volume size, compared with Equilibrium Crystal Shape (ECS) theory, is induced by the Indium self-surfactant effects, in which Indium adlayer on the top surface of InN islands will depress the thermodynamic driving force for the vertical growth of 3D islands. Lateral growth of 3D islands is not only the result of kinetic process but also favored by thermodynamics while Indium self-surfactant exist.
Federal Register 2010, 2011, 2012, 2013, 2014
2010-12-29
... necessary to ensure that DoD has continued access to advice on systems architecture and systems engineering..., not just those aspects unique to MDAPs and systems engineering and technical assistance (SETA... industrial base. Response: This comment is now moot, since DoD decided to remove the comprehensive coverage...
Plontke, Stefan K; Siedow, Norbert; Wegener, Raimund; Zenner, Hans-Peter; Salt, Alec N
2007-01-01
Cochlear fluid pharmacokinetics can be better represented by three-dimensional (3D) finite-element simulations of drug dispersal. Local drug deliveries to the round window membrane are increasingly being used to treat inner ear disorders. Crucial to the development of safe therapies is knowledge of drug distribution in the inner ear with different delivery methods. Computer simulations allow application protocols and drug delivery systems to be evaluated, and may permit animal studies to be extrapolated to the larger cochlea of the human. A finite-element 3D model of the cochlea was constructed based on geometric dimensions of the guinea pig cochlea. Drug propagation along and between compartments was described by passive diffusion. To demonstrate the potential value of the model, methylprednisolone distribution in the cochlea was calculated for two clinically relevant application protocols using pharmacokinetic parameters derived from a prior one-dimensional (1D) model. In addition, a simplified geometry was used to compare results from 3D with 1D simulations. For the simplified geometry, calculated concentration profiles with distance were in excellent agreement between the 1D and the 3D models. Different drug delivery strategies produce very different concentration time courses, peak concentrations and basal-apical concentration gradients of drug. In addition, 3D computations demonstrate the existence of substantial gradients across the scalae in the basal turn. The 3D model clearly shows the presence of drug gradients across the basal scalae of guinea pigs, demonstrating the necessity of a 3D approach to predict drug movements across and between scalae with larger cross-sectional areas, such as the human, with accuracy. This is the first model to incorporate the volume of the spiral ligament and to calculate diffusion through this structure. Further development of the 3D model will have to incorporate a more accurate geometry of the entire inner ear and incorporate more of the specific processes that contribute to drug removal from the inner ear fluids. Appropriate computer models may assist in both drug and drug delivery system design and can thus accelerate the development of a rationale-based local drug delivery to the inner ear and its successful establishment in clinical practice. Copyright 2007 S. Karger AG, Basel.
Plontke, Stefan K.; Siedow, Norbert; Wegener, Raimund; Zenner, Hans-Peter; Salt, Alec N.
2006-01-01
Hypothesis: Cochlear fluid pharmacokinetics can be better represented by three-dimensional (3D) finite-element simulations of drug dispersal. Background: Local drug deliveries to the round window membrane are increasingly being used to treat inner ear disorders. Crucial to the development of safe therapies is knowledge of drug distribution in the inner ear with different delivery methods. Computer simulations allow application protocols and drug delivery systems to be evaluated, and may permit animal studies to be extrapolated to the larger cochlea of the human. Methods: A finite-element 3D model of the cochlea was constructed based on geometric dimensions of the guinea pig cochlea. Drug propagation along and between compartments was described by passive diffusion. To demonstrate the potential value of the model, methylprednisolone distribution in the cochlea was calculated for two clinically relevant application protocols using pharmacokinetic parameters derived from a prior one-dimensional (1D) model. In addition, a simplified geometry was used to compare results from 3D with 1D simulations. Results: For the simplified geometry, calculated concentration profiles with distance were in excellent agreement between the 1D and the 3D models. Different drug delivery strategies produce very different concentration time courses, peak concentrations and basal-apical concentration gradients of drug. In addition, 3D computations demonstrate the existence of substantial gradients across the scalae in the basal turn. Conclusion: The 3D model clearly shows the presence of drug gradients across the basal scalae of guinea pigs, demonstrating the necessity of a 3D approach to predict drug movements across and between scalae with larger cross-sectional areas, such as the human, with accuracy. This is the first model to incorporate the volume of the spiral ligament and to calculate diffusion through this structure. Further development of the 3D model will have to incorporate a more accurate geometry of the entire inner ear and incorporate more of the specific processes that contribute to drug removal from the inner ear fluids. Appropriate computer models may assist in both drug and drug delivery system design and can thus accelerate the development of a rationale-based local drug delivery to the inner ear and its successful establishment in clinical practice. PMID:17119332
An approach for representing sensor data to validate alerts in Ambient Assisted Living.
Muñoz, Andrés; Serrano, Emilio; Villa, Ana; Valdés, Mercedes; Botía, Juan A
2012-01-01
The mainstream of research in Ambient Assisted Living (AAL) is devoted to developing intelligent systems for processing the data collected through artificial sensing. Besides, there are other elements that must be considered to foster the adoption of AAL solutions in real environments. In this paper we focus on the problem of designing interfaces among caregivers and AAL systems. We present an alert management tool that supports carers in their task of validating alarms raised by the system. It generates text-based explanations--obtained through an argumentation process--of the causes leading to alarm activation along with graphical sensor information and 3D models, thus offering complementary types of information. Moreover, a guideline to use the tool when validating alerts is also provided. Finally, the functionality of the proposed tool is demonstrated through two real cases of alert.
Mechatronics Interface for Computer Assisted Prostate Surgery Training
NASA Astrophysics Data System (ADS)
Altamirano del Monte, Felipe; Padilla Castañeda, Miguel A.; Arámbula Cosío, Fernando
2006-09-01
In this work is presented the development of a mechatronics device to simulate the interaction of the surgeon with the surgical instrument (resectoscope) used during a Transurethral Resection of the Prostate (TURP). Our mechatronics interface is part of a computer assisted system for training in TURP, which is based on a 3D graphics model of the prostate which can be deformed and resected interactively by the user. The mechatronics interface, is the device that the urology residents will manipulate to simulate the movements performed during surgery. Our current prototype has five degrees of freedom, which are enough to have a realistic simulation of the surgery movements. Two of these degrees of freedom are linear, to determinate the linear displacement of the resecting loop and the other three are rotational to determinate three directions and amounts of rotation.
NASA Astrophysics Data System (ADS)
Shariati, Mohsen; Khosravinejad, Fariba
The gas nanosensor of indium oxide nanowires in laser assisted approach, doped with tin and zinc for gas sensing and 1D growth purposes respectively, was reported. The nanowires were very sensitive to H2S gas in low concentration of 20ppb gas at room temperature. The fast dynamic intensive and sensitive response to gas was in a few seconds with an on/off sensitivity ratio of around 10. The square cross-section indium oxide nanowires were fabricated through physical vapor deposition (PVD) mechanism and annealing approach. The field emission scanning electron microscopy (FESEM) observations indicated that the annealing temperature was vital in nanostructures’ morphology. The fabricated nanowires for the optimized annealing temperature in applied growth technique were around 60nm in diameter.
Hoganson, David M; Pryor, Howard I; Bassett, Erik K; Spool, Ira D; Vacanti, Joseph P
2011-02-21
There is no technology available to support failing lung function for patients outside the hospital. An implantable lung assist device would augment lung function as a bridge to transplant or possible destination therapy. Utilizing biomimetic design principles, a microfluidic vascular network was developed for blood inflow from the pulmonary artery and blood return to the left atrium. Computational fluid dynamics analysis was used to optimize blood flow within the vascular network. A micro milled variable depth mold with 3D features was created to achieve both physiologic blood flow and shear stress. Gas exchange occurs across a thin silicone membrane between the vascular network and adjacent alveolar chamber with flowing oxygen. The device had a surface area of 23.1 cm(2) and respiratory membrane thickness of 8.7 ± 1.2 μm. Carbon dioxide transfer within the device was 156 ml min(-1) m(-2) and the oxygen transfer was 34 ml min(-1) m(-2). A lung assist device based on tissue engineering architecture achieves gas exchange comparable to hollow fiber oxygenators yet does so while maintaining physiologic blood flow. This device may be scaled up to create an implantable ambulatory lung assist device.
Renkawitz, Tobias; Tingart, Markus; Grifka, Joachim; Sendtner, Ernst; Kalteis, Thomas
2009-09-01
This article outlines the scientific basis and a state-of-the-art application of computer-assisted orthopedic surgery in total hip arthroplasty (THA) and provides a future perspective on this technology. Computer-assisted orthopedic surgery in primary THA has the potential to couple 3D simulations with real-time evaluations of surgical performance, which has brought these developments from the research laboratory all the way to clinical use. Nonimage- or imageless-based navigation systems without the need for additional pre- or intra-operative image acquisition have stood the test to significantly reduce the variability in positioning the acetabular component and have shown precise measurement of leg length and offset changes during THA. More recently, computer-assisted orthopedic surgery systems have opened a new frontier for accurate surgical practice in minimally invasive, tissue-preserving THA. The future generation of imageless navigation systems will switch from simple measurement tasks to real navigation tools. These software algorithms will consider the cup and stem as components of a coupled biomechanical system, navigating the orthopedic surgeon to find an optimized complementary component orientation rather than target values intraoperatively, and are expected to have a high impact on clinical practice and postoperative functionality in modern THA.
1979-03-01
0. E. Macha contributed greatly as co— researchers and their efforts are sincerely appreciated . The abl e laboratory assistance of Mr. Charl es Bel l...the author ’s colleagues at the AIr Force Materials Laboratory . P0~ values were determined along the crack line behind the crack tip by D. E. Macha ...m t . J. of Fracture Mech., 7 (1971), 487-490. 31. W. El ber, Engineering Fracture Mechanics , 2 (1970), 37-45. ¶ 32. 3. W. Jones , 0. E. Macha
2011-05-04
Linton, Walker Hardy, Vinay Gupta , and Daniel Noon. “STAR–TIDES and Starfish Networks: Supporting Stressed Populations with Distributed Talent...42 Jatinder Gupta , Sushil K. Sharma, and Jeffery Hsu, “An Overview of Knowledge Management,” in Creating Knowledge Based Organizations, ed...Jatinder N. D. Gupta et al. (Hershey, PA: Idea Group Publishing, 2004), 3-5. 43 Ibid, 15. 44 Ibid, 16. 45 Dwyer, Wells, “STAR-TIDES: Haiti earthquake
Stereoconversion of amino acids and peptides in uryl-pendant binol schiff bases.
Park, Hyunjung; Nandhakumar, Raju; Hong, Jooyeon; Ham, Sihyun; Chin, Jik; Kim, Kwan Mook
2008-01-01
(S)-2-Hydroxy-2'-(3-phenyluryl-benzyl)-1,1'-binaphthyl-3-carboxaldehyde (1) forms Schiff bases with a wide range of nonderivatized amino acids, including unnatural ones. Multiple hydrogen bonds, including resonance-assisted ones, fix the whole orientation of the imine and provoke structural rigidity around the imine C==N bond. Due to the structural difference and the increase in acidity of the alpha proton of the amino acid, the imine formed with an L-amino acid (1-l-aa) is converted into the imine of the D-amino acid (1-D-aa), with a D/L ratio of more than 10 for most amino acids at equilibrium. N-terminal amino acids in dipeptides are also predominantly epimerized to the D form upon imine formation with 1. Density functional theory calculations show that 1-D-Ala is more stable than 1-L-Ala by 1.64 kcal mol(-1), a value that is in qualitative agreement with the experimental result. Deuterium exchange of the alpha proton of alanine in the imine form was studied by (1)H NMR spectroscopy and the results support a stepwise mechanism in the L-into-D conversion rather than a concerted one; that is, deprotonation and protonation take place in a sequential manner. The deprotonation rate of L-Ala is approximately 16 times faster than that of D-Ala. The protonation step, however, appears to favor L-amino acid production, which prevents a much higher predominance of the D form in the imine. Receptor 1 and the predominantly D-form amino acid can be recovered from the imine by simple extraction under acidic conditions. Hence, 1 is a useful auxiliary to produce D-amino acids of industrial interest by the conversion of naturally occurring L-amino acids or relatively easily obtainable racemic amino acids.
Xiao, Yanju; Sun, Xiumei; Wang, Lin; Zhang, Yaoyao; Chen, Kai; Wu, Guomin
2017-12-01
Because of the limitation of specific preoperative design and surgical templates, orthognathic surgery and mandibular contour osteoplasty are generally performed in two stages. Three-dimensional printing technology has improved the accuracy of the surgery and results in good surgical predictability easily. This study aims to confirm the effectiveness, feasibility and precision of simultaneous mandibular contour osteoplasty and orthognathic surgery with the assistance of 3D printing technology. Ten patients, who were diagnosed with mandibular hypertrophy and bimaxillary deformities, were included in the study. In addition to conventional orthognathic surgery, mandibular angle ostectomy, mandibular outer cortex grinding or mandibular border ostectomy was designed for mandibular hypertrophy. Optimal osteotomy lines and simulated surgeries were designed according the 3D printing model of the mandible. Then, surgical templates were made on the 3D printing model. No muscle excision was performed in any patient. Preoperative, predicted and postoperative measurements were taken, including the gonial angle (Ar-Go-Me) and the mandibular width (Go-Go). All the patients had a reposeful postoperative recovery, with no indication of obvious infection, facial paralysis, osteonecrosis or bone displacement. The gonial angle was improved from 110.3° ± 11.1 to 121.3° ± 2.9, and the mandibular width was improved from 117.5 mm ± 6.8 to 111.9 mm ± 4.2. The discrepancies between simulation and postoperation of the left gonial angle, the right gonial angle and the mandibular width were 0.56° ± 0.22, 0.65° ± 0.3 and 0.49 mm ± 0.43, respectively. The results of our study illustrated the predictability, feasibility and reliability of simultaneous mandibular contour osteoplasty and orthognathic surgery with the assistance of 3D printing technology. Our technique could achieve functional improvement and an aesthetic profile at the same time. This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .
Oshiro, Yukio; Ohkohchi, Nobuhiro
2017-06-01
To perform accurate hepatectomy without injury, it is necessary to understand the anatomical relationship among the branches of Glisson's sheath, hepatic veins, and tumor. In Japan, three-dimensional (3D) preoperative simulation for liver surgery is becoming increasingly common, and liver 3D modeling and 3D hepatectomy simulation by 3D analysis software for liver surgery have been covered by universal healthcare insurance since 2012. Herein, we review the history of virtual hepatectomy using computer-assisted surgery (CAS) and our research to date, and we discuss the future prospects of CAS. We have used the SYNAPSE VINCENT medical imaging system (Fujifilm Medical, Tokyo, Japan) for 3D visualization and virtual resection of the liver since 2010. We developed a novel fusion imaging technique combining 3D computed tomography (CT) with magnetic resonance imaging (MRI). The fusion image enables us to easily visualize anatomic relationships among the hepatic arteries, portal veins, bile duct, and tumor in the hepatic hilum. In 2013, we developed an original software, called Liversim, which enables real-time deformation of the liver using physical simulation, and a randomized control trial has recently been conducted to evaluate the use of Liversim and SYNAPSE VINCENT for preoperative simulation and planning. Furthermore, we developed a novel hollow 3D-printed liver model whose surface is covered with frames. This model is useful for safe liver resection, has better visibility, and the production cost is reduced to one-third of a previous model. Preoperative simulation and navigation with CAS in liver resection are expected to help planning and conducting a surgery and surgical education. Thus, a novel CAS system will contribute to not only the performance of reliable hepatectomy but also to surgical education.
44 CFR 361.3 - Project description.
Code of Federal Regulations, 2014 CFR
2014-10-01
... Section 361.3 Emergency Management and Assistance FEDERAL EMERGENCY MANAGEMENT AGENCY, DEPARTMENT OF... centers and national defense facilities. (d) Each fiscal year, FEMA will establish a target allocation of... to those hazards; (2) Earthquake hazards reduction accomplishments of the State to date; (3) State...
44 CFR 361.3 - Project description.
Code of Federal Regulations, 2013 CFR
2013-10-01
... Section 361.3 Emergency Management and Assistance FEDERAL EMERGENCY MANAGEMENT AGENCY, DEPARTMENT OF... centers and national defense facilities. (d) Each fiscal year, FEMA will establish a target allocation of... to those hazards; (2) Earthquake hazards reduction accomplishments of the State to date; (3) State...
44 CFR 361.3 - Project description.
Code of Federal Regulations, 2012 CFR
2012-10-01
... Section 361.3 Emergency Management and Assistance FEDERAL EMERGENCY MANAGEMENT AGENCY, DEPARTMENT OF... centers and national defense facilities. (d) Each fiscal year, FEMA will establish a target allocation of... to those hazards; (2) Earthquake hazards reduction accomplishments of the State to date; (3) State...
Hubert, Jane; Chollet, Sébastien; Purson, Sylvain; Reynaud, Romain; Harakat, Dominique; Martinez, Agathe; Nuzillard, Jean-Marc; Renault, Jean-Hugues
2015-07-24
The aqueous-ethanolic extract of Tephrosia purpurea seeds is currently exploited in the cosmetic industry as a natural ingredient of skin lotions. The aim of this study was to chemically characterize this ingredient by combining centrifugal partition extraction (CPE) as a fractionation tool with two complementary identification approaches involving dereplication and computer-assisted structure elucidation. Following two rapid fractionations of the crude extract (2 g), seven major compounds namely, caffeic acid, quercetin-3-O-rutinoside, ethyl galactoside, ciceritol, stachyose, saccharose, and citric acid, were unambiguously identified within the CPE-generated simplified mixtures by a recently developed (13)C NMR-based dereplication method. The structures of four additional compounds, patuletin-3-O-rutinoside, kaempferol-3-O-rutinoside, guaiacylglycerol 8-vanillic acid ether, and 2-methyl-2-glucopyranosyloxypropanoic acid, were automatically elucidated by using the Logic for Structure Determination program based on the interpretation of 2D NMR (HSQC, HMBC, and COSY) connectivity data. As more than 80% of the crude extract mass was characterized without need for tedious and labor-intensive multistep purification procedures, the identification tools involved in this work constitute a promising strategy for an efficient and time-saving chemical profiling of natural extracts.
Interprofessional Peer-Assisted Learning as a Model of Instruction in Doctor of Audiology Programs.
Serpanos, Yula C; Senzer, Deborah; Gordon, Daryl M
2017-09-18
This study reports on interprofessional peer-assisted learning (PAL) as a model of instruction in the preparation of doctoral audiology students. Ten Doctor of Audiology (AuD) students provided training in audiologic screening for 53 graduate speech-language pathology students in 9 individual PAL sessions. Pre- and post-surveys assessed the peer teaching experience for AuD students in 5 areas of their confidence in audiologic screening: knowledge, skill, making a referral based on outcomes, teaching, and supervising. Pre- and post-learning outcomes in audiologic screening for the speech-language pathology student trainees determined the effectiveness of training by their AuD student peers. Survey outcomes revealed significant (p < .001) improvement in the overall confidence of AuD student peer instructors. Speech-language pathology students trained by their AuD peers exhibited significant (p = .003) improvements in their knowledge and skill and making outcome-based referrals in audiologic screening, supporting the effectiveness of the PAL paradigm. In addition to meeting required accreditation and professional certification competency standards, the PAL instructional model offers an innovative curricular approach in interprofessional education and in the teaching and supervisory preparation of students in doctoral audiology programs.
View of the SBS-4 communications satellite in orbit above the earth
1984-08-30
41D-39-068 (1 Sept 1984) --- Quickly moving away from the Space Shuttle Discovery is the Telstar 3 communications satellite, deployed September 1, 1984. The 41-D crew successfully completed three satellite placements, of which this was the last. Telstar was the second 41-D deployed satellite to be equipped with a payload assist module (PAM-D). The frame was exposed with a 70mm camera.
Visual Object Recognition with 3D-Aware Features in KITTI Urban Scenes
Yebes, J. Javier; Bergasa, Luis M.; García-Garrido, Miguel Ángel
2015-01-01
Driver assistance systems and autonomous robotics rely on the deployment of several sensors for environment perception. Compared to LiDAR systems, the inexpensive vision sensors can capture the 3D scene as perceived by a driver in terms of appearance and depth cues. Indeed, providing 3D image understanding capabilities to vehicles is an essential target in order to infer scene semantics in urban environments. One of the challenges that arises from the navigation task in naturalistic urban scenarios is the detection of road participants (e.g., cyclists, pedestrians and vehicles). In this regard, this paper tackles the detection and orientation estimation of cars, pedestrians and cyclists, employing the challenging and naturalistic KITTI images. This work proposes 3D-aware features computed from stereo color images in order to capture the appearance and depth peculiarities of the objects in road scenes. The successful part-based object detector, known as DPM, is extended to learn richer models from the 2.5D data (color and disparity), while also carrying out a detailed analysis of the training pipeline. A large set of experiments evaluate the proposals, and the best performing approach is ranked on the KITTI website. Indeed, this is the first work that reports results with stereo data for the KITTI object challenge, achieving increased detection ratios for the classes car and cyclist compared to a baseline DPM. PMID:25903553
Visual Object Recognition with 3D-Aware Features in KITTI Urban Scenes.
Yebes, J Javier; Bergasa, Luis M; García-Garrido, Miguel Ángel
2015-04-20
Driver assistance systems and autonomous robotics rely on the deployment of several sensors for environment perception. Compared to LiDAR systems, the inexpensive vision sensors can capture the 3D scene as perceived by a driver in terms of appearance and depth cues. Indeed, providing 3D image understanding capabilities to vehicles is an essential target in order to infer scene semantics in urban environments. One of the challenges that arises from the navigation task in naturalistic urban scenarios is the detection of road participants (e.g., cyclists, pedestrians and vehicles). In this regard, this paper tackles the detection and orientation estimation of cars, pedestrians and cyclists, employing the challenging and naturalistic KITTI images. This work proposes 3D-aware features computed from stereo color images in order to capture the appearance and depth peculiarities of the objects in road scenes. The successful part-based object detector, known as DPM, is extended to learn richer models from the 2.5D data (color and disparity), while also carrying out a detailed analysis of the training pipeline. A large set of experiments evaluate the proposals, and the best performing approach is ranked on the KITTI website. Indeed, this is the first work that reports results with stereo data for the KITTI object challenge, achieving increased detection ratios for the classes car and cyclist compared to a baseline DPM.
Automatic 2D and 3D segmentation of liver from Computerised Tomography
NASA Astrophysics Data System (ADS)
Evans, Alun
As part of the diagnosis of liver disease, a Computerised Tomography (CT) scan is taken of the patient, which the clinician then uses for assistance in determining the presence and extent of the disease. This thesis presents the background, methodology, results and future work of a project that employs automated methods to segment liver tissue. The clinical motivation behind this work is the desire to facilitate the diagnosis of liver disease such as cirrhosis or cancer, assist in volume determination for liver transplantation, and possibly assist in measuring the effect of any treatment given to the liver. Previous attempts at automatic segmentation of liver tissue have relied on 2D, low-level segmentation techniques, such as thresholding and mathematical morphology, to obtain the basic liver structure. The derived boundary can then be smoothed or refined using more advanced methods. The 2D results presented in this thesis improve greatly on this previous work by using a topology adaptive active contour model to accurately segment liver tissue from CT images. The use of conventional snakes for liver segmentation is difficult due to the presence of other organs closely surrounding the liver this new technique avoids this problem by adding an inflationary force to the basic snake equation, and initialising the snake inside the liver. The concepts underlying the 2D technique are extended to 3D, and results of full 3D segmentation of the liver are presented. The 3D technique makes use of an inflationary active surface model which is adaptively reparameterised, according to its size and local curvature, in order that it may more accurately segment the organ. Statistical analysis of the accuracy of the segmentation is presented for 18 healthy liver datasets, and results of the segmentation of unhealthy livers are also shown. The novel work developed during the course of this project has possibilities for use in other areas of medical imaging research, for example the segmentation of internal liver structures, and the segmentation and classification of unhealthy tissue. The possibilities of this future work are discussed towards the end of the report.
Deprest, Jan; Vercauteren, Tom; Ourselin, Sebastien; David, Anna L.
2015-01-01
Abstract Fetal surgery has become a clinical reality, with interventions for twin‐to‐twin transfusion syndrome (TTTS) and spina bifida demonstrated to improve outcome. Fetal imaging is evolving, with the use of 3D ultrasound and fetal MRI becoming more common in clinical practise. Medical imaging analysis is also changing, with technology being developed to assist surgeons by creating 3D virtual models that improve understanding of complex anatomy, and prove powerful tools in surgical planning and intraoperative guidance. We introduce the concept of computer‐assisted surgical planning, and present the results of a systematic review of image reconstruction for fetal surgical planning that identified six articles using such technology. Indications from other specialities suggest a benefit of surgical planning and guidance to improve outcomes. There is therefore an urgent need to develop fetal‐specific technology in order to improve fetal surgical outcome. © 2015 The Authors. Prenatal Diagnosis published by John Wiley & Sons Ltd. PMID:26235960
2D and 3D visualization methods of endoscopic panoramic bladder images
NASA Astrophysics Data System (ADS)
Behrens, Alexander; Heisterklaus, Iris; Müller, Yannick; Stehle, Thomas; Gross, Sebastian; Aach, Til
2011-03-01
While several mosaicking algorithms have been developed to compose endoscopic images of the internal urinary bladder wall into panoramic images, the quantitative evaluation of these output images in terms of geometrical distortions have often not been discussed. However, the visualization of the distortion level is highly desired for an objective image-based medical diagnosis. Thus, we present in this paper a method to create quality maps from the characteristics of transformation parameters, which were applied to the endoscopic images during the registration process of the mosaicking algorithm. For a global first view impression, the quality maps are laid over the panoramic image and highlight image regions in pseudo-colors according to their local distortions. This illustration supports then surgeons to identify geometrically distorted structures easily in the panoramic image, which allow more objective medical interpretations of tumor tissue in shape and size. Aside from introducing quality maps in 2-D, we also discuss a visualization method to map panoramic images onto a 3-D spherical bladder model. Reference points are manually selected by the surgeon in the panoramic image and the 3-D model. Then the panoramic image is mapped by the Hammer-Aitoff equal-area projection onto the 3-D surface using texture mapping. Finally the textured bladder model can be freely moved in a virtual environment for inspection. Using a two-hemisphere bladder representation, references between panoramic image regions and their corresponding space coordinates within the bladder model are reconstructed. This additional spatial 3-D information thus assists the surgeon in navigation, documentation, as well as surgical planning.
An Automatic Registration Algorithm for 3D Maxillofacial Model
NASA Astrophysics Data System (ADS)
Qiu, Luwen; Zhou, Zhongwei; Guo, Jixiang; Lv, Jiancheng
2016-09-01
3D image registration aims at aligning two 3D data sets in a common coordinate system, which has been widely used in computer vision, pattern recognition and computer assisted surgery. One challenging problem in 3D registration is that point-wise correspondences between two point sets are often unknown apriori. In this work, we develop an automatic algorithm for 3D maxillofacial models registration including facial surface model and skull model. Our proposed registration algorithm can achieve a good alignment result between partial and whole maxillofacial model in spite of ambiguous matching, which has a potential application in the oral and maxillofacial reparative and reconstructive surgery. The proposed algorithm includes three steps: (1) 3D-SIFT features extraction and FPFH descriptors construction; (2) feature matching using SAC-IA; (3) coarse rigid alignment and refinement by ICP. Experiments on facial surfaces and mandible skull models demonstrate the efficiency and robustness of our algorithm.
Wu, Xin; Lin, Guole; Qiu, Huizhong; Xiao, Yi; Wu, Bin
2017-06-25
To analyze the clinical features, possible reasons and management of anastomotic leakage after laparoscopic-assisted radical right hemicolectomy. Clinical data of 546 patients undergoing laparoscopic-assisted radical right hemicolectomy in Peking Union Medical College Hospital from October 2010 to September 2016 were retrospectively analyzed. The occurrence of anastomotic leakage and its countermeasures were evaluated. Among 546 patients, 8(1.5%) cases developed anastomotic leakage, including 7 males and 1 female with mean age of (54.3±10.3) years. Six cases of ascending colon cancer, 1 case of phlegmon and 1 case of arterior-venous malformation were confirmed after operation. The incidence of anastomotic leakage after D3 and D2 lymphadenectomy was 2.1%(6/290) and 0.8%(2/256). The time from operation to the diagnosis of anastomotic leakage was (6.6±3.6) days. The clinical manifestation of anastomotic leakage were stool-like drainage in 7 patients, fever in 4 and abdominal pain in 3. Amylase and bilirubin in drainage of 4 patients increased obviously. All the 8 patients underwent secondary ileostomy, including 4 with laparoscopy and 4 with laparotomy. One patient suffered from respiratory failure after re-operation because of severe abdominal infection and was cured by ventilator support treatment. Another one had pelvic encapsulated effusion and was treated by puncture drainage. All the patients discharged from hospital smoothly. Anastomotic leakage after laparoscopic-assisted right hemicolectomy is a quite rare but serious complication, which may be associated with over-cleaning of lymph fatty tissues. Ileostomy should be the first choice of anastomotic leakage after laparoscopy-assisted right hemicolectomy and its efficacy is satisfactory.
Compiler-Assisted Multiple Instruction Rollback Recovery Using a Read Buffer. Ph.D. Thesis
NASA Technical Reports Server (NTRS)
Alewine, Neal Jon
1993-01-01
Multiple instruction rollback (MIR) is a technique to provide rapid recovery from transient processor failures and was implemented in hardware by researchers and slow in mainframe computers. Hardware-based MIR designs eliminate rollback data hazards by providing data redundancy implemented in hardware. Compiler-based MIR designs were also developed which remove rollback data hazards directly with data flow manipulations, thus eliminating the need for most data redundancy hardware. Compiler-assisted techniques to achieve multiple instruction rollback recovery are addressed. It is observed that data some hazards resulting from instruction rollback can be resolved more efficiently by providing hardware redundancy while others are resolved more efficiently with compiler transformations. A compiler-assisted multiple instruction rollback scheme is developed which combines hardware-implemented data redundancy with compiler-driven hazard removal transformations. Experimental performance evaluations were conducted which indicate improved efficiency over previous hardware-based and compiler-based schemes. Various enhancements to the compiler transformations and to the data redundancy hardware developed for the compiler-assisted MIR scheme are described and evaluated. The final topic deals with the application of compiler-assisted MIR techniques to aid in exception repair and branch repair in a speculative execution architecture.
Practical 3D Printing of Antennas and RF Electronics
2017-03-01
Passive RF; Combiners Introduction Additive manufacturing can reduce the time and material costs in a design cycle and enable the on-demand printing of...performance, and create Computer Assisted Manufacturing (CAM) files. By intelligently leveraging this process, the design can be readily updated or...advances in 3D printing technology now enable antennas and RF electronics to be designed and prototyped significantly faster than conventional
Jost, Gregory F; Walti, Jonas; Mariani, Luigi; Schaeren, Stefan; Cattin, Philippe
2018-05-30
Inertial measurement units (IMUs) are microelectromechanical systems used to track orientation and motion. To use instruments mounted with IMUs in combination with a 3- and 2-dimensional (3D/2D) rendering of the computed-tomography scan (CT) to guide implantation of pedicle screws. Pedicle screws were implanted from T1 to S1 in 2 human cadavers. A software application enabled the surgeon to select the starting points and trajectories on a 3D/2D image of the spine, then locate these starting points on the exposed spine and apply the IMU-mounted instruments to reproduce the trajectories. The position of the screws was evaluated on the postoperative CT scan. A total of 72 pedicle screws were implanted. Thirty-seven (77%) of the thoracic screws were within the pedicle (Heary I), 7 (15%) showed a lateral breach of the pedicle, and 4 (8%) violated the anterior or lateral vertebral body (Heary III). In the lumbar spine and S1, 21 screws (88%) were within the pedicle (Gertzbein 0), 2 (8%) screws had a pedicle wall breach < 2 mm (Gertzbein 1), and 1 > 2 to < 4 mm (Gertzbein 2). In the second cadaver, the position was compared to the intraoperatively shown virtual position. The median offset was 3°(mean 3° ± 2°, variance 5, range 0°-9°) in the sagittal plane and 3° (mean 4° ± 3°, variance 9, range 0°-12°) in the axial plane. IMU-assisted implantation of pedicle screws combined with an intraoperative 3D/2D visualization of the spine enabled the surgeon to precisely implant pedicle screws on the exposed spine.
1980-01-01
economic equity among the participants. Dr. Walter B. LaBerge , former Assistant Secretary General for Defense Sup- port, NATO, and now Deputy Under...1977. 34. Thomas A. Callaghan, President, Export-Import Technology, Inc., Washington, D.C. 35. Dr. Walter B. LaBerge , "A Concept of a Two-Way Street...one single activity-the production and acquisition : ’. 1. Steven Rosen, Testing the Theory of the Military-Industrial Complex (Lexington, Mass.: D. C
Automatic 2.5-D Facial Landmarking and Emotion Annotation for Social Interaction Assistance.
Zhao, Xi; Zou, Jianhua; Li, Huibin; Dellandrea, Emmanuel; Kakadiaris, Ioannis A; Chen, Liming
2016-09-01
People with low vision, Alzheimer's disease, and autism spectrum disorder experience difficulties in perceiving or interpreting facial expression of emotion in their social lives. Though automatic facial expression recognition (FER) methods on 2-D videos have been extensively investigated, their performance was constrained by challenges in head pose and lighting conditions. The shape information in 3-D facial data can reduce or even overcome these challenges. However, high expenses of 3-D cameras prevent their widespread use. Fortunately, 2.5-D facial data from emerging portable RGB-D cameras provide a good balance for this dilemma. In this paper, we propose an automatic emotion annotation solution on 2.5-D facial data collected from RGB-D cameras. The solution consists of a facial landmarking method and a FER method. Specifically, we propose building a deformable partial face model and fit the model to a 2.5-D face for localizing facial landmarks automatically. In FER, a novel action unit (AU) space-based FER method has been proposed. Facial features are extracted using landmarks and further represented as coordinates in the AU space, which are classified into facial expressions. Evaluated on three publicly accessible facial databases, namely EURECOM, FRGC, and Bosphorus databases, the proposed facial landmarking and expression recognition methods have achieved satisfactory results. Possible real-world applications using our algorithms have also been discussed.
Computer-aided analysis for the Mechanics of Granular Materials (MGM) experiment, part 2
NASA Technical Reports Server (NTRS)
Parker, Joey K.
1987-01-01
Computer vision based analysis for the MGM experiment is continued and expanded into new areas. Volumetric strains of granular material triaxial test specimens have been measured from digitized images. A computer-assisted procedure is used to identify the edges of the specimen, and the edges are used in a 3-D model to estimate specimen volume. The results of this technique compare favorably to conventional measurements. A simplified model of the magnification caused by diffraction of light within the water of the test apparatus was also developed. This model yields good results when the distance between the camera and the test specimen is large compared to the specimen height. An algorithm for a more accurate 3-D magnification correction is also presented. The use of composite and RGB (red-green-blue) color cameras is discussed and potentially significant benefits from using an RGB camera are presented.
Automated branching pattern report generation for laparoscopic surgery assistance
NASA Astrophysics Data System (ADS)
Oda, Masahiro; Matsuzaki, Tetsuro; Hayashi, Yuichiro; Kitasaka, Takayuki; Misawa, Kazunari; Mori, Kensaku
2015-05-01
This paper presents a method for generating branching pattern reports of abdominal blood vessels for laparoscopic gastrectomy. In gastrectomy, it is very important to understand branching structure of abdominal arteries and veins, which feed and drain specific abdominal organs including the stomach, the liver and the pancreas. In the real clinical stage, a surgeon creates a diagnostic report of the patient anatomy. This report summarizes the branching patterns of the blood vessels related to the stomach. The surgeon decides actual operative procedure. This paper shows an automated method to generate a branching pattern report for abdominal blood vessels based on automated anatomical labeling. The report contains 3D rendering showing important blood vessels and descriptions of branching patterns of each vessel. We have applied this method for fifty cases of 3D abdominal CT scans and confirmed the proposed method can automatically generate branching pattern reports of abdominal arteries.
Bone suppression in CT angiography data by region-based multiresolution segmentation
NASA Astrophysics Data System (ADS)
Blaffert, Thomas; Wiemker, Rafael; Lin, Zhong Min
2003-05-01
Multi slice CT (MSCT) scanners have the advantage of high and isotropic image resolution, which broadens the range of examinations for CT angiography (CTA). A very important method to present the large amount of high-resolution 3D data is the visualization by maximum intensity projections (MIP). A problem with MIP projections in angiography is that bones often hide the vessels of interest, especially the scull and vertebral column. Software tools for a manual selection of bone regions and their suppression in the MIP are available, but processing is time-consuming and tedious. A highly computer-assisted of even fully automated suppression of bones would considerably speed up the examination and probably increase the number of examined cases. In this paper we investigate the suppression (or removal) of bone regions in 3D CT data sets for vascular examinations of the head with a visualization of the carotids and the circle of Willis.
Benítez, Almudena; Di Lecce, Daniele; Elia, Giuseppe Antonio; Caballero, Álvaro; Morales, Julián; Hassoun, Jusef
2018-05-09
An efficient lithium-ion battery was assembled by using an enhanced sulfur-based cathode and a silicon oxide-based anode and proposed as an innovative energy-storage system. The sulfur-carbon composite, which exploits graphene carbon with a 3 D array (3DG-S), was synthesized by a reduction step through a microwave-assisted solvothermal technique and was fully characterized in terms of structure and morphology, thereby revealing suitable features for lithium-cell application. Electrochemical tests of the 3DG-S electrode in a lithium half-cell indicated a capacity ranging from 1200 to 1000 mAh g -1 at currents of C/10 and 1 C, respectively. Remarkably, the Li-alloyed anode, namely, Li y SiO x -C prepared by the sol-gel method and lithiated by surface treatment, showed suitable performance in a lithium half-cell by using an electrolyte designed for lithium-sulfur batteries. The Li y SiO x -C/3DG-S battery was found to exhibit very promising properties with a capacity of approximately 460 mAh g S -1 delivered at an average voltage of approximately 1.5 V over 200 cycles, suggesting that the characterized materials would be suitable candidates for low-cost and high-energy-storage applications. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.
Cleared DoD Employees at Risk - Report 2 A Study of Barriers to Seeking Help
2002-01-01
PERSEREC examined the relationship between DoD security policy and federally mandated employee assistance programs ( EAPs ) for civilians and...counseling/referral services for military personnel to identify any barriers for cleared DoD employees to using these programs . The study, based largely on...appendices that provides background information for the interested reader on such topics as the EAP movement, military counseling/referral programs , and DoD personnel security policies and programs .
1981-09-01
Measurement/Adult El FI~ [El 1:11] II PIES Form 326e (OT) 1 Novembeti 1978 A-3 sfti= 237 Saline IrrigatioD (Gastric)W uli il 111 Enema: Cleansing Mi...U lIED Dilatation and -Curettage/Assisting Physician ii) El Do~ EI M.1 L or Evacuation Vaginal /Pelvic Examinrations/Assisting Physician ElU L. IE l2...ADMINISTRATION: Oral -QB E ED EE ElE Suppositories Rectal/ Vaginal 1E El El El I ElD Topical MI~II iE Sublingual III ol El El El DIAGNOSTIC TESTS: Bone
Development and validation of technique for in-vivo 3D analysis of cranial bone graft survival
NASA Astrophysics Data System (ADS)
Bernstein, Mark P.; Caldwell, Curtis B.; Antonyshyn, Oleh M.; Ma, Karen; Cooper, Perry W.; Ehrlich, Lisa E.
1997-05-01
Bone autografts are routinely employed in the reconstruction of facial deformities resulting from trauma, tumor ablation or congenital malformations. The combined use of post- operative 3D CT and SPECT imaging provides a means for quantitative in vivo evaluation of bone graft volume and osteoblastic activity. The specific objectives of this study were: (1) Determine the reliability and accuracy of interactive computer-assisted analysis of bone graft volumes based on 3D CT scans; (2) Determine the error in CT/SPECT multimodality image registration; (3) Determine the error in SPECT/SPECT image registration; and (4) Determine the reliability and accuracy of CT-guided SPECT uptake measurements in cranial bone grafts. Five human cadaver heads served as anthropomorphic models for all experiments. Four cranial defects were created in each specimen with inlay and onlay split skull bone grafts and reconstructed to skull and malar recipient sites. To acquire all images, each specimen was CT scanned and coated with Technetium doped paint. For purposes of validation, skulls were landmarked with 1/16-inch ball-bearings and Indium. This study provides a new technique relating anatomy and physiology for the analysis of cranial bone graft survival.
Algorithm of pulmonary emphysema extraction using thoracic 3D CT images
NASA Astrophysics Data System (ADS)
Saita, Shinsuke; Kubo, Mitsuru; Kawata, Yoshiki; Niki, Noboru; Nakano, Yasutaka; Ohmatsu, Hironobu; Tominaga, Keigo; Eguchi, Kenji; Moriyama, Noriyuki
2007-03-01
Recently, due to aging and smoking, emphysema patients are increasing. The restoration of alveolus which was destroyed by emphysema is not possible, thus early detection of emphysema is desired. We describe a quantitative algorithm for extracting emphysematous lesions and quantitatively evaluate their distribution patterns using low dose thoracic 3-D CT images. The algorithm identified lung anatomies, and extracted low attenuation area (LAA) as emphysematous lesion candidates. Applying the algorithm to thoracic 3-D CT images and then by follow-up 3-D CT images, we demonstrate its potential effectiveness to assist radiologists and physicians to quantitatively evaluate the emphysematous lesions distribution and their evolution in time interval changes.
Algorithm of pulmonary emphysema extraction using low dose thoracic 3D CT images
NASA Astrophysics Data System (ADS)
Saita, S.; Kubo, M.; Kawata, Y.; Niki, N.; Nakano, Y.; Omatsu, H.; Tominaga, K.; Eguchi, K.; Moriyama, N.
2006-03-01
Recently, due to aging and smoking, emphysema patients are increasing. The restoration of alveolus which was destroyed by emphysema is not possible, thus early detection of emphysema is desired. We describe a quantitative algorithm for extracting emphysematous lesions and quantitatively evaluate their distribution patterns using low dose thoracic 3-D CT images. The algorithm identified lung anatomies, and extracted low attenuation area (LAA) as emphysematous lesion candidates. Applying the algorithm to 100 thoracic 3-D CT images and then by follow-up 3-D CT images, we demonstrate its potential effectiveness to assist radiologists and physicians to quantitatively evaluate the emphysematous lesions distribution and their evolution in time interval changes.
Karbalaei Akbari, Mohammad; Hai, Zhenyin; Wei, Zihan; Detavernier, Christophe; Solano, Eduardo; Verpoort, Francis; Zhuiykov, Serge
2018-03-28
Electrically responsive plasmonic devices, which benefit from the privilege of surface plasmon excited hot carries, have supported fascinating applications in the visible-light-assisted technologies. The properties of plasmonic devices can be tuned by controlling charge transfer. It can be attained by intentional architecturing of the metal-semiconductor (MS) interfaces. In this study, the wafer-scaled fabrication of two-dimensional (2D) TiO 2 semiconductors on the granular Au metal substrate is achieved using the atomic layer deposition (ALD) technique. The ALD-developed 2D MS heterojunctions exhibited substantial enhancement of the photoresponsivity and demonstrated the improvement of response time for 2D Au-TiO 2 -based plasmonic devices under visible light illumination. To circumvent the undesired dark current in the plasmonic devices, a 2D WO 3 nanofilm (∼0.7 nm) was employed as the intermediate layer on the MS interface to develop the metal-insulator-semiconductor (MIS) 2D heterostructure. As a result, 13.4% improvement of the external quantum efficiency was obtained for fabricated 2D Au-WO 3 -TiO 2 heterojunctions. The impedancometry measurements confirmed the modulation of charge transfer at the 2D MS interface using MIS architectonics. Broadband photoresponsivity from the UV to the visible light region was observed for Au-TiO 2 and Au-WO 3 -TiO 2 heterostructures, whereas near-infrared responsivity was not observed. Consequently, considering the versatile nature of the ALD technique, this approach can facilitate the architecturing and design of novel 2D MS and MIS heterojunctions for efficient plasmonic devices.
Li, Ming-Hsien; Yeh, Hung-Hsiang; Chiang, Yu-Hsien; Jeng, U-Ser; Su, Chun-Jen; Shiu, Hung-Wei; Hsu, Yao-Jane; Kosugi, Nobuhiro; Ohigashi, Takuji; Chen, Yu-An; Shen, Po-Shen; Chen, Peter; Guo, Tzung-Fang
2018-06-08
The fabrication of multidimensional organometallic halide perovskite via a low-pressure vapor-assisted solution process is demonstrated for the first time. Phenyl ethyl-ammonium iodide (PEAI)-doped lead iodide (PbI 2 ) is first spin-coated onto the substrate and subsequently reacts with methyl-ammonium iodide (MAI) vapor in a low-pressure heating oven. The doping ratio of PEAI in MAI-vapor-treated perovskite has significant impact on the crystalline structure, surface morphology, grain size, UV-vis absorption and photoluminescence spectra, and the resultant device performance. Multiple photoluminescence spectra are observed in the perovskite film starting with high PEAI/PbI 2 ratio, which suggests the coexistence of low-dimensional perovskite (PEA 2 MA n -1 Pb n I 3 n +1 ) with various values of n after vapor reaction. The dimensionality of the as-fabricated perovskite film reveals an evolution from 2D, hybrid 2D/3D to 3D structure when the doping level of PEAI/PbI 2 ratio varies from 2 to 0. Scanning electron microscopy images and Kelvin probe force microscopy mapping show that the PEAI-containing perovskite grain is presumably formed around the MAPbI 3 perovskite grain to benefit MAPbI 3 grain growth. The device employing perovskite with PEAI/PbI 2 = 0.05 achieves a champion power conversion efficiency of 19.10% with an open-circuit voltage of 1.08 V, a current density of 21.91 mA cm -2 , and a remarkable fill factor of 80.36%. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Li, M. Y.; Yang, H. F.; Zhang, Z. H.; Gu, J. H.; Yang, S. H.
2016-01-01
A universally applicable method for promoting the fast formation and growth of high-density Sn whiskers on solders was developed by fabricating Mg/Sn-based solder/Mg joints using ultrasonic-assisted soldering at 250 °C for 6 s and then subjected to thermal aging at 25 °C for 7 d. The results showed that the use of the ultrasonic-assisted soldering could produce the supersaturated dissolution of Mg in the liquid Sn and lead to the existence of two forms of Mg in Sn after solidification. Moreover, the formation and growth of the high-density whiskers were facilitated by the specific contributions of both of the Mg forms in the solid Sn. Specifically, interstitial Mg can provide the persistent driving force for Sn whisker growth, whereas the Mg2Sn phase can increase the formation probability of Sn whiskers. In addition, we presented that the formation and growth of Sn whiskers in the Sn-based solders can be significantly restricted by a small amount of Zn addition (≥3 wt.%), and the prevention mechanisms are attributed to the segregation of Zn atoms at grain or phase boundaries and the formation of the lamellar-type Zn-rich structures in the solder. PMID:27273421
Zhang, Yaqing; Wen, Lianjiang; Zhang, Jun; Yan, Guoliang; Zhou, Yue; Huang, Bo
2017-01-01
Abstract Rationale: Three-dimensional (3D) printed templates can be designed to match an individual's anatomy, allowing surgeons to refine preoperative planning. In addition, the use of computer navigation (NAV) is gaining popularity to improve surgical accuracy in the resection of pelvic tumors. However, its use in combination with 3D printing to assist complex pelvic tumor resection has not been reported. Patient concerns: A 36-year-old man presented with left-sided pelvic pain and a fast-growing mass. He also complained of a 3-month history of radiating pain and numbness in the lower left extremity. Diagnoses: A biopsy revealed an osteochondroma with malignant potential. This osteochondroma arises from the ilium and involves the sacrum and lower lumbar vertebrae. Interventions: Here, we describe a novel combined application of 3D printing and intraoperative NAV systems to guide hemipelvectomy for en-bloc resection of the osteochondroma. The 3D printed template is analyzed during surgical planning and guides the initial intraoperative bone work to improve surgical accuracy and efficiency, while a computer NAV system provides real-time imaging during the tumor removal to achieve adequate resection margins and minimize the likelihood of injury to adjacent critical structures. Outcomes: The tumor mass and the invaded spinal structures were removed en bloc. Lessons: The combined application of 3D printing and computer NAV may be useful for tumor targeting and safe osteotomies in pelvic tumor surgery. PMID:28328842
Context-Based Mobile Security Enclave
2012-09-01
29 c. Change IMSI .............................30 d. Change CellID ...........................31 e. Change Geolocation ...Assisted Global Positioning System ADB Android Debugger API Application Programming Interface APK Android Application Package BSC Base Station...Programming Interfaces ( APIs ), which use Java compatible libraries based on Apache Harmony (an open source Java implementation developed by the Apache
NASA Astrophysics Data System (ADS)
Stylianidis, E.; Valaria, E.; Smagas, K.; Pagani, A.; Henriques, J.; Garca, A.; Jimeno, E.; Carrillo, I.; Patias, P.; Georgiadis, C.; Kounoudes, A.; Michail, K.
2016-06-01
There is a continuous and increasing demand for solutions, both software and hardware-based, that are able to productively handle underground utilities geospatial data. Innovative approaches that are based on the use of the European GNSS, Galileo and EGNOS, sensor technologies and LBS, are able to monitor, document and manage utility infrastructures' data with an intuitive 3D augmented visualisation and navigation/positioning technology. A software and hardware-based system called LARA, currently under develop- ment through a H2020 co-funded project, aims at meeting that demand. The concept of LARA is to integrate the different innovative components of existing technologies in order to design and develop an integrated navigation/positioning and information system which coordinates GNSS, AR, 3D GIS and geodatabases on a mobile platform for monitoring, documenting and managing utility infrastruc- tures on-site. The LARA system will guide utility field workers to locate the working area by helping them see beneath the ground, rendering the complexity of the 3D models of the underground grid such as water, gas and electricity. The capacity and benefits of LARA are scheduled to be tested in two case studies located in Greece and the United Kingdom with various underground utilities. The paper aspires to present the first results from this initiative. The project leading to this application has received funding from the European GNSS Agency under the European Union's Horizon 2020 research and innovation programme under grant agreement No 641460.
NASA Astrophysics Data System (ADS)
McConnell, William J.
Due to the call of current science education reform for the integration of engineering practices within science classrooms, design-based instruction is receiving much attention in science education literature. Although some aspect of modeling is often included in well-known design-based instructional methods, it is not always a primary focus. The purpose of this study was to better understand how design-based instruction with an emphasis on scientific modeling might impact students' spatial abilities and their model-based argumentation abilities. In the following mixed-method multiple case study, seven seventh grade students attending a secular private school in the Mid-Atlantic region of the United States underwent an instructional intervention involving design-based instruction, modeling and argumentation. Through the course of a lesson involving students in exploring the interrelatedness of the environment and an animal's form and function, students created and used multiple forms of expressed models to assist them in model-based scientific argument. Pre/post data were collected through the use of The Purdue Spatial Visualization Test: Rotation, the Mental Rotation Test and interviews. Other data included a spatial activities survey, student artifacts in the form of models, notes, exit tickets, and video recordings of students throughout the intervention. Spatial abilities tests were analyzed using descriptive statistics while students' arguments were analyzed using the Instrument for the Analysis of Scientific Curricular Arguments and a behavior protocol. Models were analyzed using content analysis and interviews and all other data were coded and analyzed for emergent themes. Findings in the area of spatial abilities included increases in spatial reasoning for six out of seven participants, and an immense difference in the spatial challenges encountered by students when using CAD software instead of paper drawings to create models. Students perceived 3D printed models to better assist them in scientific argumentation over paper drawing models. In fact, when given a choice, students rarely used paper drawing to assist in argument. There was also a difference in model utility between the two different model types. Participants explicitly used 3D printed models to complete gestural modeling, while participants rarely looked at 2D models when involved in gestural modeling. This study's findings added to current theory dealing with the varied spatial challenges involved in different modes of expressed models. This study found that depth, symmetry and the manipulation of perspectives are typically spatial challenges students will attend to using CAD while they will typically ignore them when drawing using paper and pencil. This study also revealed a major difference in model-based argument in a design-based instruction context as opposed to model-based argument in a typical science classroom context. In the context of design-based instruction, data revealed that design process is an important part of model-based argument. Due to the importance of design process in model-based argumentation in this context, trusted methods of argument analysis, like the coding system of the IASCA, was found lacking in many respects. Limitations and recommendations for further research were also presented.
Liang, Shih-Shin; Wang, Tsu-Nai; Chiu, Chien-Chih; Kuo, Po-Lin; Huang, Mei-Fang; Liu, Meng-Chieh; Tsai, Eing-Mei
2016-02-19
Tamoxifen, a hormonal therapy drug against estrogen receptor-positive breast cancer, can be metabolized by cytochrome P450 enzymes such as CYP3A4 and CYP3A5, and converted to N-desmethyltamoxifen, which is subsequently, metabolized by CYP2D6 and inverted to form 4-hydroxy-N-desmethyltamoxifen (endoxifen). Conventional mass spectrometry (MS) analyses of tamoxifen and its metabolites require isotopic internal standards (ISs). In this study, endoxifen and N-desmethyltamoxifen amine groups were modified by reductive amination with formaldehyde-D2 to produce new metabolite molecules. Both endoxifen and N-desmethyltamoxifen generated their corresponding D2-methyl modified analogs. This method is expected to simplify MS detection and overcome the difficulty in selecting adequate ISs when tamoxifen metabolites are analyzed by absolute quantification. It identified tamoxifen, D2-methyl modified endoxifen, and D2-methyl modified N-desmethyltamoxifen with a linearity ranging from 2 to 5000 ng/mL with correlation coefficient (R(2)) values of 0.9868, 0.9849, and 0.9880, respectively. Furthermore, this reductive amination-based method may enhance the signal intensities of D2-methyl modified N-desmethyltamoxifen and endoxifen, thus facilitating the MS detection. Copyright © 2016 Elsevier B.V. All rights reserved.
Zuo, Yi; Wan, Xiangjian; Long, Guankui; Kan, Bin; Ni, Wang; Zhang, Hongtao; Chen, Yongsheng
2015-07-15
In order to understand the photovoltaic performance differences between the recently reported DR3TBTT-HD and DR3TBDT2T based solar cells, a modified two-diode model with Hecht equation was built to simulate the corresponding current-voltage characteristics. The simulation results reveal that the poor device performance of the DR3TBDTT-HD based device mainly originated from its insufficient charge transport ability, where an average current of 5.79 mA cm(-2) was lost through this pathway at the maximum power point for the DR3TBDTT-HD device, nearly three times as large as that of the DR3TBDT2T based device under the same device fabrication conditions. The morphology studies support these simulation results, in which both Raman and 2D-GIXD data reveal that DR3TBTT-HD based blend films exhibit lower crystallinity. Spin coating at low temperature was used to increase the crystallinity of DR3TBDTT-HD based blend films, and the average current loss through insufficient charge transport at maximum power point was suppressed to 2.08 mA cm(-2). As a result, the average experimental power conversion efficiency of DR3TBDTT-HD based solar cells increased by over 40%.
Percolation of light through whispering gallery modes in 3D lattices of coupled microspheres.
Astratov, Vasily N; Ashili, Shashanka P
2007-12-10
Using techniques of flow-assisted self-assembly we synthesized three-dimensional (3D) lattices of dye-doped fluorescent (FL) 5 mum polystyrene spheres with 3% size dispersion with well controlled thickness from one monolayer up to 43 monolayers. In FL transmission spectra of such lattices we observed signatures of coupling between multiple spheres with nearly resonant whispering gallery modes (WGMs). These include (i) splitting of the WGM-related peaks with the magnitude 4.0-5.3 nm at the average wavelength 535 nm, (ii) pump dependence of FL transmission showing that the splitting is seen only above the threshold for lasing WGMs, and (iii) anomalously high transmission at the WGM peak wavelengths compared to the background for samples with thickness around 25 mum. We propose a qualitative interpretation of the observed WGM transport based on an analogy with percolation theory where the sites of the lattice (spheres) are connected with optical "bonds" which are present with probability depending on the spheres' size dispersion. We predict that the WGM percolation threshold should be achievable in close packed 3D lattices formed by cavities with ~10(3) quality factors of WGMs and with ~1% size dispersion. Such systems can be used for developing next generation of resonant sensors and arrayed-resonator light emitting devices.
Targeting of deep-brain structures in nonhuman primates using MR and CT Images
NASA Astrophysics Data System (ADS)
Chen, Antong; Hines, Catherine; Dogdas, Belma; Bone, Ashleigh; Lodge, Kenneth; O'Malley, Stacey; Connolly, Brett; Winkelmann, Christopher T.; Bagchi, Ansuman; Lubbers, Laura S.; Uslaner, Jason M.; Johnson, Colena; Renger, John; Zariwala, Hatim A.
2015-03-01
In vivo gene delivery in central nervous systems of nonhuman primates (NHP) is an important approach for gene therapy and animal model development of human disease. To achieve a more accurate delivery of genetic probes, precise stereotactic targeting of brain structures is required. However, even with assistance from multi-modality 3D imaging techniques (e.g. MR and CT), the precision of targeting is often challenging due to difficulties in identification of deep brain structures, e.g. the striatum which consists of multiple substructures, and the nucleus basalis of meynert (NBM), which often lack clear boundaries to supporting anatomical landmarks. Here we demonstrate a 3D-image-based intracranial stereotactic approach applied toward reproducible intracranial targeting of bilateral NBM and striatum of rhesus. For the targeting we discuss the feasibility of an atlas-based automatic approach. Delineated originally on a high resolution 3D histology-MR atlas set, the NBM and the striatum could be located on the MR image of a rhesus subject through affine and nonrigid registrations. The atlas-based targeting of NBM was compared with the targeting conducted manually by an experienced neuroscientist. Based on the targeting, the trajectories and entry points for delivering the genetic probes to the targets could be established on the CT images of the subject after rigid registration. The accuracy of the targeting was assessed quantitatively by comparison between NBM locations obtained automatically and manually, and finally demonstrated qualitatively via post mortem analysis of slices that had been labelled via Evan Blue infusion and immunohistochemistry.
NASA Astrophysics Data System (ADS)
Tronganh, Nguyen; Gao, Yang; Jiang, Wei; Tao, Haihua; Wang, Shanshan; Zhao, Bing; Jiang, Yong; Chen, Zhiwen; Jiao, Zheng
2018-05-01
Constructing heterostructure can endow composites with many novel physical and electrochemical properties due to the built-in specific charge transfer dynamics. However, controllable fabrication route to heterostructures is still a great challenge up to now. In this work, a SiO2-assisted hydrothermal method is developed to fabricate heterostructured nickel sulfides/reduced graphene oxide (NiSx/rGO) composite. The SiO2 particles hydrolyzed from tetraethyl orthosilicate could assist the surface controllable co-growth of 3D nanoflowers and 0D nanoparticles of Ni3S2/NiS decorated on reduced graphene oxide, and the possible co-growth mechanism is discussed in detail. In this composite, the heterostructured nanocomposite with different morphologies, chemical compositions and crystal structures, along with varied electronic states and band structure, can promote the interface charge transfer kinetics and lead to excellent lithium storage performances. Electrochemical measurements reveal that the NiSx/rGO composite presents 1187.0 mA h g-1 at 100 mA g-1 and achieves a highly stable capacity of 561.2 mA h g-1 even when the current density is up to 5 A g-1.
NASA Astrophysics Data System (ADS)
Ota, Shunsuke; Deguchi, Daisuke; Kitasaka, Takayuki; Mori, Kensaku; Suenaga, Yasuhito; Hasegawa, Yoshinori; Imaizumi, Kazuyoshi; Takabatake, Hirotsugu; Mori, Masaki; Natori, Hiroshi
2008-03-01
This paper presents a method for automated anatomical labeling of bronchial branches (ALBB) extracted from 3D CT datasets. The proposed method constructs classifiers that output anatomical names of bronchial branches by employing the machine-learning approach. We also present its application to a bronchoscopy guidance system. Since the bronchus has a complex tree structure, bronchoscopists easily tend to get disoriented and lose the way to a target location. A bronchoscopy guidance system is strongly expected to be developed to assist bronchoscopists. In such guidance system, automated presentation of anatomical names is quite useful information for bronchoscopy. Although several methods for automated ALBB were reported, most of them constructed models taking only variations of branching patterns into account and did not consider those of running directions. Since the running directions of bronchial branches differ greatly in individuals, they could not perform ALBB accurately when running directions of bronchial branches were different from those of models. Our method tries to solve such problems by utilizing the machine-learning approach. Actual procedure consists of three steps: (a) extraction of bronchial tree structures from 3D CT datasets, (b) construction of classifiers using the multi-class AdaBoost technique, and (c) automated classification of bronchial branches by using the constructed classifiers. We applied the proposed method to 51 cases of 3D CT datasets. The constructed classifiers were evaluated by leave-one-out scheme. The experimental results showed that the proposed method could assign correct anatomical names to bronchial branches of 89.1% up to segmental lobe branches. Also, we confirmed that it was quite useful to assist the bronchoscopy by presenting anatomical names of bronchial branches on real bronchoscopic views.
Automatic localization of the da Vinci surgical instrument tips in 3-D transrectal ultrasound.
Mohareri, Omid; Ramezani, Mahdi; Adebar, Troy K; Abolmaesumi, Purang; Salcudean, Septimiu E
2013-09-01
Robot-assisted laparoscopic radical prostatectomy (RALRP) using the da Vinci surgical system is the current state-of-the-art treatment option for clinically confined prostate cancer. Given the limited field of view of the surgical site in RALRP, several groups have proposed the integration of transrectal ultrasound (TRUS) imaging in the surgical workflow to assist with accurate resection of the prostate and the sparing of the neurovascular bundles (NVBs). We previously introduced a robotic TRUS manipulator and a method for automatically tracking da Vinci surgical instruments with the TRUS imaging plane, in order to facilitate the integration of intraoperative TRUS in RALRP. Rapid and automatic registration of the kinematic frames of the da Vinci surgical system and the robotic TRUS probe manipulator is a critical component of the instrument tracking system. In this paper, we propose a fully automatic registration technique based on automatic 3-D TRUS localization of robot instrument tips pressed against the air-tissue boundary anterior to the prostate. The detection approach uses a multiscale filtering technique to identify and localize surgical instrument tips in the TRUS volume, and could also be used to detect other surface fiducials in 3-D ultrasound. Experiments have been performed using a tissue phantom and two ex vivo tissue samples to show the feasibility of the proposed methods. Also, an initial in vivo evaluation of the system has been carried out on a live anaesthetized dog with a da Vinci Si surgical system and a target registration error (defined as the root mean square distance of corresponding points after registration) of 2.68 mm has been achieved. Results show this method's accuracy and consistency for automatic registration of TRUS images to the da Vinci surgical system.
Anchorage in Orthodontics: Three-dimensional Scanner Input
Nabbout, Fidele; Baron, Pascal
2018-01-01
Aims and Objectives: The aim of this article is to re-evaluate anchorage coefficient values in orthodontics and their influence in the treatment decision through the usage of three-dimensional (3D) scanner. Materials and Methods: A sample of 80 patients was analyzed with the 3D scanner using the C2000 and Cepha 3DT softwares (CIRAD Montpellier, France). Tooth anatomy parameters (linear measurements, root, and crown volumes) were then calculated to determine new anchorage coefficients based on root volume. Data were collected and statistically evaluated with the StatView software (version 5.0). Results: The anchorage coefficient values found in this study are compared to those established in previous studies. These new values affect and modify our approach in orthodontic treatment from the standpoint of anchorage. Conclusion: The use of new anchorage coefficient values has significant clinical implications in conventional and in microimplants-assisted orthodontic mechanics through the selection and delivery of the optimal force system (magnitude and moment) for an adequate biological response. PMID:29629323
1999-07-01
a novel mechanism. Work from the Gumbiner lab has shown that B-catenin can import itself without assistance from the standard importin- based nuclear...Cavallo, D. Dooijes, M. van Beest , J. van Es, J. Loureiro, A. Ypma, D. Hursh, T. Jones, A. Bejsovec, M. Peifer, M. Mortin and H. Clevers. 1997
Robust Spacecraft Component Detection in Point Clouds.
Wei, Quanmao; Jiang, Zhiguo; Zhang, Haopeng
2018-03-21
Automatic component detection of spacecraft can assist in on-orbit operation and space situational awareness. Spacecraft are generally composed of solar panels and cuboidal or cylindrical modules. These components can be simply represented by geometric primitives like plane, cuboid and cylinder. Based on this prior, we propose a robust automatic detection scheme to automatically detect such basic components of spacecraft in three-dimensional (3D) point clouds. In the proposed scheme, cylinders are first detected in the iteration of the energy-based geometric model fitting and cylinder parameter estimation. Then, planes are detected by Hough transform and further described as bounded patches with their minimum bounding rectangles. Finally, the cuboids are detected with pair-wise geometry relations from the detected patches. After successive detection of cylinders, planar patches and cuboids, a mid-level geometry representation of the spacecraft can be delivered. We tested the proposed component detection scheme on spacecraft 3D point clouds synthesized by computer-aided design (CAD) models and those recovered by image-based reconstruction, respectively. Experimental results illustrate that the proposed scheme can detect the basic geometric components effectively and has fine robustness against noise and point distribution density.
Robust Spacecraft Component Detection in Point Clouds
Wei, Quanmao; Jiang, Zhiguo
2018-01-01
Automatic component detection of spacecraft can assist in on-orbit operation and space situational awareness. Spacecraft are generally composed of solar panels and cuboidal or cylindrical modules. These components can be simply represented by geometric primitives like plane, cuboid and cylinder. Based on this prior, we propose a robust automatic detection scheme to automatically detect such basic components of spacecraft in three-dimensional (3D) point clouds. In the proposed scheme, cylinders are first detected in the iteration of the energy-based geometric model fitting and cylinder parameter estimation. Then, planes are detected by Hough transform and further described as bounded patches with their minimum bounding rectangles. Finally, the cuboids are detected with pair-wise geometry relations from the detected patches. After successive detection of cylinders, planar patches and cuboids, a mid-level geometry representation of the spacecraft can be delivered. We tested the proposed component detection scheme on spacecraft 3D point clouds synthesized by computer-aided design (CAD) models and those recovered by image-based reconstruction, respectively. Experimental results illustrate that the proposed scheme can detect the basic geometric components effectively and has fine robustness against noise and point distribution density. PMID:29561828
Zhou, Guangni; Zhu, Wenxin; Shen, Hao; ...
2016-06-15
Synchrotron-based Laue microdiffraction has been widely applied to characterize the local crystal structure, orientation, and defects of inhomogeneous polycrystalline solids by raster scanning them under a micro/nano focused polychromatic X-ray probe. In a typical experiment, a large number of Laue diffraction patterns are collected, requiring novel data reduction and analysis approaches, especially for researchers who do not have access to fast parallel computing capabilities. In this article, a novel approach is developed by plotting the distributions of the average recorded intensity and the average filtered intensity of the Laue patterns. Visualization of the characteristic microstructural features is realized in realmore » time during data collection. As an example, this method is applied to image key features such as microcracks, carbides, heat affected zone, and dendrites in a laser assisted 3D printed Ni-based superalloy, at a speed much faster than data collection. Such analytical approach remains valid for a wide range of crystalline solids, and therefore extends the application range of the Laue microdiffraction technique to problems where real-time decision-making during experiment is crucial (for instance time-resolved non-reversible experiments).« less
Zhou, Guangni; Zhu, Wenxin; Shen, Hao; Li, Yao; Zhang, Anfeng; Tamura, Nobumichi; Chen, Kai
2016-01-01
Synchrotron-based Laue microdiffraction has been widely applied to characterize the local crystal structure, orientation, and defects of inhomogeneous polycrystalline solids by raster scanning them under a micro/nano focused polychromatic X-ray probe. In a typical experiment, a large number of Laue diffraction patterns are collected, requiring novel data reduction and analysis approaches, especially for researchers who do not have access to fast parallel computing capabilities. In this article, a novel approach is developed by plotting the distributions of the average recorded intensity and the average filtered intensity of the Laue patterns. Visualization of the characteristic microstructural features is realized in real time during data collection. As an example, this method is applied to image key features such as microcracks, carbides, heat affected zone, and dendrites in a laser assisted 3D printed Ni-based superalloy, at a speed much faster than data collection. Such analytical approach remains valid for a wide range of crystalline solids, and therefore extends the application range of the Laue microdiffraction technique to problems where real-time decision-making during experiment is crucial (for instance time-resolved non-reversible experiments). PMID:27302087
32 CFR 37.1285 - Expenditure-based award.
Code of Federal Regulations, 2010 CFR
2010-07-01
... purposes for which the award was made. Most Federal Government grants and cooperative agreements are... National Defense Department of Defense OFFICE OF THE SECRETARY OF DEFENSE DoD GRANT AND AGREEMENT...-based award. A Federal Government contract or assistance award for which the amounts of interim payments...
Code of Federal Regulations, 2013 CFR
2013-01-01
.... (c) Weather and climate. (1) Serve as a focal point within the Department for coordination of weather, climate, and related crop monitoring activities. (d) Remote sensing. (1) Provide technical assistance...