bluuebunny/crossref_metadata_2025_split huggingface dataset:
Electronics and the Technology Gap—the Case of Numerically Controlled Machine Tools
Authors: Jacobsson Staffan 
Published: August 2010

SUMMARY This article is concerned with the introduction of electronic control devices (‘numerical controls’) in machine tools. This has provided substantial benefits to firms in that it saves both capital and labour, improves product quality and reduces the time required to bring new products onto the market. Whilst these advantages may appear to benefit developed countries disproportionately, the most significant benefit conferred is probably in relation to the saving of skilled labour. Since skilled labour is the major element in the developed countries' comparative advantage, it is likely that the diffusion ot these machine tools will move comparative advantage in favour of the newly industrialising countries (NICs). However, the article concludes with the warning that advances in automation technology will probably reduce this temporary shift.RESUME L'électronique et le fossé technologique: le cas des machines‐outils à commande numériqueCet article concerne l'introduction de dispositifs de commande numérique sur les machines‐outils. Les avantages: économies de capital et de main‐d'oeuvre, amélioration de la qualité et déduction des délais de production. Ils paraissent donner aux pays développés plusieurs longueurs d'avance, mais le principal est l'économie de main‐d'oeuvre qualifiée. Puisque cet élément est le plus important des avantages des pays développés, il est probable que la diffusion de ces machines‐outils profite surtout aux pays d'industrialisation récente. L'article conclut cependant que les progrès de l'automation finiront par compenser probablement cette évolution temporaire.RESUMEN La electrónica y las diferencias tecnológicas: el caso de las máquinas‐herramienta de control numéricoEste artículo se concentra en la introducción de los dispositivos de control electrónico (‘controles numéricos’) en las máquinas‐herramienta. Esto ha proporcionado beneficios importantes a las empresas porque ahorra tanto capital como mano de obra, mejora la calidad del producto y reduce el tiempo necesario para introducir nuevos productos en el mercado. Aunque estas ventajas parezcan beneficiar a los países desarrollados de una manera desproporcionada, el beneficio más importante que se obtiene está probablemente relacionado con el ahorro de mano de obra especializada. Como le mano de obra especializada es el elemento más importante en la ventaja comparativa de los países desarrollados, es probable que la divulgación de estas máquinas‐herramienta traslade esta ventaja comparativa en favor de los países recientemente industrializados. No obstante, el artículo concluye con un aviso de que los progresos realizados en la tecnología automatizada probablemente reducirá este cambio provisional.
Europe and the South in the 1980s: prospects for political change
Authors: Ramphal Shridath S. 
Published: August 2010

SUMMARY The USA may be withdrawing from active involvement in North‐South issues. Europe, too, has dragged its feet in the various North‐South fora. Yet the challenge of the South is growing, and is evident in figures on debt, deteriorating terms of trade and protectionism. The EEC has a major role to play in reversing the deterioration of North‐South relations. The Community, in particular, has more interest in the Third World than do some of the member states. It should build on the on the Lomé framework, and move out to other Third World countries.RESUMEN Europa y el Sur en la década 1980Estados Unidos puede retirarse del compromiso activo en los asuntos Norte‐Sur y también Europa ha perdido interés en los diversos foros sobre el tema. No obstante, el desafío del Sur está creciendo y se hace evidente en las cifras de la deuda, el deterioro de los términos de intercambio y el proteccionismo. La CEE tiene un importante rol que cumplir en revertir el deterioro de las relaciones Norte‐Sur. La Comunidad, en especial, tiene más interés en el Tercer Mundo que algunos de los estados miembros y debería basarse en el marco de Lomé y orientarse a otros países del Tercer Mundo.RÉSUMÉ L'Europe et le Sud dans les années 80Les Etats‐Unis envisageraient un retrait de leur participation active dans les problèmes Nord‐Sud. L'Europe aussi a été lente à réagir dans les divers forums Nord‐Sud. Cependant le défi du Sud s'accroît, et cela est évident dans les chiffres des dettes, détériorant les conditions du commerce et du protectionnisme. La CEE a un rôle majeur à jouer dans le retournement de la situation de détérioration des relations Nord‐Sud. La Communauté, en particulier, a plus d'intérêts dans le Tiers‐Monde que certains états‐membres. Elle devrait mettre en place le projet de Lomé, et se tourner vers d'autres pays du Tiers‐Monde.
SU‐BB‐201B‐03: The AAPM Resources for Continuing Education ‐ Increasing Effectiveness for the Future
Authors: Limmer J 
Published: August 2010

This presentation will include a discussion of the resources available in the Virtual Library, the opportunities for Continuing Education and SAMs credits on‐line, and actions planed or underway to increase the overall effectiveness in meeting the CE/SAMs needs of the membership.Learning Objectives:1. The existing resources in the AAPM Virtual Library2. The current opportunities for CE and SAMs on line through AAPM3. The plans for future developments in meeting the CE needs of membership through on‐line educational experiences.
SU‐GG‐J‐24: Retrospective Clinical Data Analysis of Fiducial‐Free Lung Tracking
Authors: Jordan P , West J , Sharda A , Maurer C 
Published: August 2010

Purpose: To present the algorithmic approach used in the Xsight® Lung Tracking System (XLT; Accuray Incorporated, Sunnyvale, CA) of the CyberKnife® Robotic Radiosurgery System (Accuray Incorporated) and to quantify the expected proportion of lung radiosurgery candidates suitable for fiducial‐free motion‐compensated treatment using orthogonal kV imaging. Method and Materials: The XLT system was recently enhanced with the goal of increasing the proportion of lung lesions that can be tracked in orthogonal kV x‐ray image pairs without fiducials. These enhancements include digitally reconstructed radiographs generated from local tumor neighborhoods, an automatic preferred projection epipolar constraint, tumor template matching allowing for in‐plane rotations, and automatic x‐ray image enhancement. An extensive multi‐institutional (M=5) cohort of patients (N=103) was retrospectively analyzed to quantify fiducial‐free target localization performance for lung tumors spanning a broad range of anatomical locations and sizes (largest dimension ranged from 10 to 100 mm). This analysis evaluated 7,565 x‐ray image pairs to quantify the localization performance of the XLT system in comparison to fiducial localization as a gold standard. Clinical cases were categorized as “fiducial‐free candidates” when XLT localization satisfied preset accuracy, quality assurance and detection confidence metrics in over 75% of the tested image pairs. Results: A total of 57 out of 103 cases (55.3%) were found to be suitable candidates for fiducial‐free treatment. The site‐specific fiducial‐free candidate ratios ranged from 40% to 78% of all lung radiosurgery candidates, reflecting variability in patient population, tumor locations and sizes (algorithm works best for tumors larger than 15 mm in diameter), and x‐ray imaging technique. Conclusion: This study demonstrates that fiducial‐free localization and motion compensation can be achieved in over half of lung radiosurgery candidates using the recently enhanced XLT system, while maintaining tracking accuracy comparable to that obtained using implanted fiducial markers.Conflict of Interest: The authors are employed by Accuray Incorporated.
SU‐GG‐T‐338: Accuracy of Superficial Dose Calculation for Breast Cancer Treatments on Tomotherapy
Authors: Green O Pechenaya , Goddu S , Rodriguez V , Cates J , Michaletz‐Lorenz M , Zoberi I 
Published: August 2010

Purpose: To evaluate the effect of breathing motion and setup error on the accuracy of treatment planning surface dose calculation for breast cancer treatments on helical Tomotherapy. Method and Materials: In‐vivo dosimetry with MOSFET detectors was performed on a cohort of patients treated for breast cancer on helical Tomotherapy. The detectors were placed under the 0.5‐cm tissue‐equivalent bolus used for patient treatments. The pre‐treatment MVCT images were used to localize the MOSFET detectors. Tomotherapy's Planned Adaptive software was used to compare the measurements against both the planned surface doses at the locations of the dosimeters as well as the recalculated doses based on the MVCT scan. This allowed for evaluation of the combined impact of breathing and setup error on the surface dose contribution, and the quantification of dosimetric accuracy of the Tomotherapy treatment planning system for breast cancer patients. Results: The differences between dose values at the locations of the dosimeters from the plan and those calculated from the MVCT image were on average within 1% of each other. The average dosimetric differences between measured and calculated doses were 7.8 and 8 percent for the planned and adaptive calculated doses, respectively. Overall, the treatment planning system overestimated the dose at the skin/bolus interface. Conclusion: The treatment planning system was previously shown to overestimate dose at a 5‐mm depth by about 4%. The possible setup error is taken into account by the adaptive software since it recalculates the dose distribution based on the MVCT image associated with the treatment for which the measurement was made. Since the setup error was shown to be within 1%, it is therefore estimated that the dosimetric consequence of breathing motion may be as high as 3%.Conflict of Interest: This work was partially supported by a grant from Tomotherapy, Inc.
SU‐GG‐T‐427: Development of Monte Carlo Dose Verification System for MHI‐TM2000
Authors: Ishihara Y , Sawada A , Nakamura M , Kaneko S , Takayama K , Mizowaki T , Kokubo M , Hiraoka M 
Published: August 2010

Purpose: MHI‐TM2000 is an innovative image‐guided radiotherapy system with a C‐band X‐ray head on an O‐ring shaped gantry. We are developing an integrated Monte Carlo (MC) dose calculation system for four‐dimensional radiotherapy using MHI‐TM2000. The purposes of this study were to propose specific MC models of the X‐ray head and the multi‐leaf collimator (MLC) for MHI‐TM2000 and to validate their accuracy. Methods and Materials: 6 MV photon beam delivered by the MHI‐TM2000 unit was implemented by EGSnrc/BEAMnrc and EGSnrc/DOSXYZnrc. Subsequently, the X‐ray head composed of a target, a primary collimator, a flattening filter, a monitor chamber, a fixed secondary collimator, and a MLC was simulated based on the specification. Next, the central axis depth doses and the lateral doses at 15, 100, and 200 mm depth were simulated under the source to surface distance (SSD) of 900 mm. Then, Each of them was compared with the corresponding measurements using a CC06 ionization chamber and a water phantom. For the MLC model, Tongue‐and‐Groove (100 mm depth, SSD 900 mm), leaf leakage (50 mm depth, SSD 950 mm), and round leaf effects (100 mm depth, SSD 900 mm) were simulated. Meanwhile film measurements were performed using EDR2 film and a solid water phantom under similar conditions. These doses were normalized to the corresponding doses for the open field at the isocenter. The differences between simulated and measured doses were calculated. Results: For the X‐ray head, depth doses beyond the buildup region and lateral doses within the region of flatness showed agreement of within 1.3%. For each MLC test, the simulated and measured doses agreed less than 3.0%, respectively. Conclusions: We have demonstrated that the proposed MC models of the X‐ray head and the MLC for MHI‐TM2000 have reasonable accuracy.Conflicts of Interest: Research sponsored in part by Mitsubishi Heavy Industries, Ltd.
MO‐A‐204C‐01: Pulse Sequences and Acquisition Techniques for Breast MRI
Authors: Price R 
Published: August 2010

Dynamic contrast enhanced MRI (DCE‐MRI) of the breast using a gadolinium contrast agent has become an important diagnostic tool for evaluating disease extent, monitoring therapy response and for screening women that are at high risk for breast cancer.The sensitivity of DCE‐MRI for detecting cancerous lesions is primarily determined by the degree of contrast enhancement that can be achieved relative to the surrounding normal tissues. The specificity of DCE‐MRI, for distinguishing malignant from benign lesions, often relies upon the DCE‐MRI kinetic data. Malignant lesions generally exhibit rapid uptake and washout while benign lesions typically have a slower uptake that gradually increases with time.In an effort to achieve both the high sensitivity and specifically, breast MRI pulse sequences should be optimized to achieve high gadolinium contrast enhancement, high three‐dimensional spatial resolution (< 1 mm in‐plane) as well as adequate temporal resolution. The evolution of breast MR imaging has lead to the general use of fat‐suppressed, 3D T1‐weighted gradient‐echo pulse sequences that can be acquired with a temporal resolution of approximately 60 seconds.Learning Objectives:1. Review protocols and pulse sequences used for breast MR imaging.2. Review the MRI timing diagram used for T1‐weighted, fat‐suppressed, 3D gradient echo‐pulse sequences.3. Understand how k‐space sampling affects temporal resolution.4. Review how parallel imaging can be used to help achieve the temporal resolution needed for breast DCE‐MRI.5. Discuss issues related to data acquisition and post‐acquisition image processing.
MO‐B‐204C‐01: Practical Aspects of Medical Physics Surveys of Mammography Equipment and Facilities
Authors: Martin M 
Published: August 2010

Some of the practical aspects of performing the required medical physics evaluations of both digital and film/screen mammography equipment and facilities will be presented and discussed based on the experience of surveying all brands of mammography equipment for the past 15 years. A complete list of the required tests for both digital and film/screen systems will be covered with tips for completing these tests in an efficient and practical manner to minimize the time required for the facility to be without access to their equipment. Facility evaluation not only includes the mammography equipment but also the viewing conditions for the radiologists and technologists workstations for digital systems as well as the viewboxes in clinical use for film/screen systems. A review process of the printers and processors as appropriate is required for a complete facility evaluation. The mammography physicist must be familiar with all of the tests required to be performed by the mammography technologist as part of the MQSA required Quality Control Program. At each annual review, the physicist must perform a complete review of the QC program and should make any suggestions appropriate to improve the images obtained at the facility.Learning Objectives:1. Attendees will know the Annual Tests required to be performed by the medical physicist to meet MQSA and ACR accreditation requirements for both Digital and Film/Screen Mammography Equipment.2. Attendees will be aware of efficient methods to be used to perform the required tests to meet accreditation requirements.3. Attendees will made familiar with the required tests for laser printers and monitors for digital systems and for film processors and viewboxes for film/screen systems.
TU‐B‐201C‐01: Gamma Camera and SPECT Routine Quality Assurance Testing
Authors: White S 
Published: August 2010

Routine quality control, calibration and performance testing of gamma cameras are necessary in order to consistently acquire good quality images without artifacts. This lecture will briefly cover the basics of gamma camera image formation and performance characteristics. The lecture will primarily focus on routine quality assurance tests for gamma cameras.It is increasingly common for providers of nuclear medicine imaging services to seek accreditation, either from the American College of Radiology (ACR) or the Intersocietal Commission for Accreditation of Nuclear Medicine Laboratories (ICANL). Both accrediting bodies recommend routine quality control tests and these tests will be discussed.Common problems and image artifacts will be discussed as well as how to correct these problems. Calibration procedures such as center of rotation and uniformity calibration will be discussed.Learning Objectives:1. Learn the basics of gamma camera and SPECT performance measurements and quality assurance test procedures.2. Become familiar with routine quality control tests recommended by accreditation programs.3. Be able to identify and correct common problems and image artifacts in gamma camera and SPECT imaging.
TU‐D‐204C‐03: Machine Learning for Medical Image Processing and Pattern Recognition
Authors: Suzuki K 
Published: August 2010

Machine learning plays an essential role in medical image analysis, because objects such as lesions and organs in medical images cannot be modeled accurately by simple equations; thus, tasks in medical image analysis require essentially “learning from examples.” One of the most popular uses of machine learning in medical image analysis is the classification of objects such as lesions into certain categories (e.g., abnormal or normal, lesions or non‐lesions). This class of machine leaning uses features (e.g., diameter, contrast, and circularity) extracted from segmented objects as information for classifying the objects. Machine learning techniques in this class include linear discriminant analysis, a k‐nearest neighbor classifier, an artificial neural network, and a support vector machine.Recently, as available computational power increased dramatically, a new class of machine learning called pixel/voxel‐based machine learning emerged in medical image processing and analysis, which uses pixel/voxel values in images directly instead of calculated features as input information; thus, feature calculation is not required. Because pixel/voxel‐based machine learning can avoid errors caused by inaccurate segmentation and feature calculation, the performance of the pixel/voxel‐based machine learning can be better than common feature‐based machine learning. Such advanced machine‐learning techniques in this class include neural filters, neural edge enhancers, massive‐training artificial neural networks, convolution neural networks, and shift‐invariant neural networks. This lecture will provide an overview of techniques, methodologies, and applications of machine learning used in medical image processing and pattern recognition, which have been developed and advanced mainly in the field of diagnostic radiology in the past two decades or so. The applications of these machine‐learning techniques include quantum noise reduction, enhancement of the boundary of an organ, lesion enhancement, classification of lesions, and computer‐aided diagnosis. Once we have learned such machine‐learning techniques and methodologies, they can be translated quickly into new techniques for solution of problems in radiation therapy.Learning Objectives:1. Understand the basic principle of machine‐learning techniques2. Learn various techniques in the two major classes of feature‐based and mitationsof machine learning3. Understand the advantages and limitations of machine‐learning techniques4. Learn applications of machine‐learning techniques in medical image processing and pattern recognition5. Consider applications of machine‐learning techniques and methodologies in the field of radiation therapy
WE‐A‐204C‐01: Magnetic Resonance Safety and Compatibility Issues at High Magnetic Fields
Authors: Clarke G 
Published: August 2010

This review address a number of areas of safety concern in MRI, emphasizing those that gain increased importance for high‐field (≥ 3 Tesla) MRI systems. First, the effects of magnetic fields on the patient will be discussed, including the main, Bo magnetic fields. Topics shall include physiological concerns and regulatory guidelines applicable to the magnitude of the magnetic field strength. Second, the biological effects of radiofrequency (RF) magnetic fields will be addressed, introducing the concepts of eddy currents, specific absorption rate (SAR) and the Food and Drug Administration's (FDA) guidelines that deal with this topic. Finally, physiological consequences of pulsed gradient fields will be covered, including the audible noise generated by the gradient coils, nerve stimulation experienced in gradient‐intense pulse sequences and the FDA's guidelines regarding limitations and control of dB/dt. This presentation will also include a discussion on approaches to managing the MRI system's magnetic fields effects on the environment, including unanticipated flying objects (UFOs), the ACR Zone system for MRI suite plans and a detailed review of patient contraindications for MRI studies. Patient safety issues also include the description of the risks of using gadolinium (Gd)‐based and superparamagnetic iron oxide (SPIO) contrast agents. A brief discussion of the risks to pregnant patients and clinical MRI workers will also be included. Finally, the causes and dangers of superconducting magnet malfunction, focusing on cryogen boil‐off, safety switch design, spontaneous quenches and controlled quenches will be undertaken.At the end of this presentation the attendee should be able to:▪ discuss the major biological effects that can be arise from the magnetic fields produced by high‐field MRI systems.▪ enumerate the safety concerns engendered by the used of exogenous contrast agents in MRI.▪ explain the safety features that should be incorporated in the design of the MRI suite to reduced adverse events due to UFOs, patient heating and magnet quenches.