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Most readers of Medical Physics are undoubtedly aware of the open-access movement that is growing in scientific publishing circles. This movement originated because librarians, administrators, and researchers became concerned about rapidly increasing subscription rates for scientific journals managed by commercial publishers. For several years these rates have been increasing at 2–3 times the general rate of inflation. Adding emphasis to the movement is the growing belief that research publications supported by taxpayer dollars should be accessible to the public without charge. Today, research funders such as the Howard Hughes Medical Institute and the Wellcome Foundation require that recipients of research funding must publish in open-access journals. Also, some institutions in the United States and elsewhere “strongly encourage” their faculty to publish only in open-access journals. Recipients of research funds from the National Institutes of Health are not required to publish in open-access journals. However, they must post their articles on PubMed Central, an open-access site maintained by the Library of Medicine, within 12 months of publication. For articles published in Medical Physics, this posting is done automatically when authors indicate that their research was performed with support from the NIH. Many scientific journals are managed by a professional organization rather than a commercial publisher. Medical Physics is an example. It is owned by the AAPM and its publisher is the American Institute of Physics, both nonprofit organizations. The AAPM benefits greatly by its ownership of Medical Physics, because the international stature of the Journal reflects favorably on the AAPM and its members. The AAPM benefits financially as well, because one-third of its annual revenue comes from advertising in and subscriptions to Medical Physics. This revenue is used to support the activities of the AAPM, including its scientific and educational outreach programs to medical physicists throughout the world. Finally, subscription to Medical Physics is provided automatically without extra charge as a benefit of membership in the AAPM. Many articles published in Medical Physics are open access and may be downloaded free of charge as soon as they are published electronically. Among these articles are AAPM Reports, Anniversary Papers, Vision 20/20 Articles, Review Articles, Editor's Pick Articles, Point/Counterpoint Debates, Award Papers, Special Focus Papers, Editorials and Ph.D. Abstracts. All of these open-access papers are labeled “free-open access” in the Journal's Table of Contents, and are accessible under the open-access tab at http://online.medphys.org. There are three categories of open-access journals. One category is referred to as “green” open access. Journals in this category permit authors to post their papers on their personal or their institution's website as soon as the article is published. Medical Physics has been a “green” open-access journal for several years. There is no fee and no embargo period for this type of open access to Medical Physics articles. The second category of open access is described as “gold” open access. Journals in this category publish all articles open access for a fee paid by the authors. A “gold” open-access journal contains only open-access articles. The third class of journals is referred to as “hybrid gold” open access. These journals offer authors the option to publish their articles open access for a fee, but authors are not obligated to exercise this option. They may still publish their articles in the journals without a fee, but these articles will not be open access. Until now, Medical Physics has not embraced either the “gold” or “hybrid gold” model of open-access publishing. Beginning as of January 1, 2013, the Journal's Editorial Board and the AAPM Journal Business Management Committee have agreed to add the “hybrid gold” open-access feature to the Journal. Any author who wishes to have his/her article published as open access may do so for a fee of $2500.00. The article will be labeled as open access and free in the Journal's Table of Contents and on the Journal's website as soon as it is published. Of course, articles in Medical Physics that are identified in the third paragraph of this editorial are published open access without a fee. The fraction of articles published in the Journal under the open-access option will be monitored and incorporated into future considerations of subscription rates. One might ask why a fee is necessary to publish an article open access in Medical Physics. The answer is that as Medical Physics publishes more of its content open access, the pricing model for Medical Physics subscriptions will have to change to more fairly reflect the residual value of a subscription. The fee, termed an “article processing charge,” is necessary to ensure the stability of revenue to the AAPM. Medical Physics is most fortunate to have a highly productive and responsive peer-review system that depends entirely on volunteers. The Journal has only one full-time employee, the Journal Manager. The Editor is paid part-time, as is his administrative assistant. This financial arrangement will likely change when a new editor takes over in 2014. All referees and associate editors for Medical Physics are volunteers who contribute to the peer-review process without reimbursement. Because these individuals are physicists engaged in research and clinical applications of medical physics, and because they are selected individually for their expertise related to the subject of an article, the peer-review process works very well for Medical Physics. Further, it is highly responsive. For the past several years, the time has averaged 35 days between selection of an associate editor for an article and receipt of the reviews from the referees. We will not allow the addition of “hybrid gold” open-access publishing to compromise the Journal's integrity or performance in any manner, including its stellar peer-review process. For example, all reviewers of Medical Physics articles, including the editor, will be blinded with regard to whether or not the authors have requested an article to be published “hybrid gold” open access. No one is able to predict just where the open-access movement in scientific publishing is headed. Many new open-access journals have appeared, and several readers of Medical Physics, including myself, have been invited to serve on the editorial boards of such journals. In the spirit of continuing to offer the medical physics community the highest-quality journal and services possible, the Medical Physics Editorial Board and I hope that the first loyalty of those receiving such invitations will continue to be to Medical Physics.

The American Association of Physicists in Medicine (AAPM) is a nonprofit professional society whose primary purposes are to advance the science, education and professional practice of medical physics. The AAPM has more than 8,000 members and is the principal organization of medical physicists in the United States. The AAPM will periodically define new practice guidelines for medical physics practice to help advance the science of medical physics and to improve the quality of service to patients throughout the United States. Existing medical physics practice guidelines will be reviewed for the purpose of revision or renewal, as appropriate, on their fifth anniversary or sooner. Each medical physics practice guideline represents a policy statement by the AAPM, has undergone a thorough consensus process in which it has been subjected to extensive review, and requires the approval of the Professional Council. The medical physics practice guidelines recognize that the safe and effective use of diagnostic and therapeutic radiology requires specific training, skills, and techniques, as described in each document. Reproduction or modification of the published practice guidelines and technical standards by those entities not providing these services is not authorized. The following terms are used in the AAPM practice guidelines:• Must and Must Not: Used to indicate that adherence to the recommendation is considered necessary to conform to this practice guideline.• Should and Should Not: Used to indicate a prudent practice to which exceptions may occasionally be made in appropriate circumstances.

BACKGROUND: Geant4 is a Monte Carlo code extensively used in medical physics for a wide range of applications, such as dosimetry, micro- and nanodosimetry, imaging, radiation protection, and nuclear medicine. Geant4 is continuously evolving, so it is crucial to have a system that benchmarks this Monte Carlo code for medical physics against reference data and to perform regression testing. AIMS: To respond to these needs, we developed G4-Med, a benchmarking and regression testing system of Geant4 for medical physics. MATERIALS AND METHODS: G4-Med currently includes 18 tests. They range from the benchmarking of fundamental physics quantities to the testing of Monte Carlo simulation setups typical of medical physics applications. Both electromagnetic and hadronic physics processes and models within the prebuilt Geant4 physics lists are tested. The tests included in G4-Med are executed on the CERN computing infrastructure via the use of the geant-val web application, developed at CERN for Geant4 testing. The physical observables can be compared to reference data for benchmarking and to results of previous Geant4 versions for regression testing purposes. RESULTS: This paper describes the tests included in G4-Med and shows the results derived from the benchmarking of Geant4 10.5 against reference data. DISCUSSION: Our results indicate that the Geant4 electromagnetic physics constructor G4EmStandardPhysics_option4 gives a good agreement with the reference data for all the tests. The QGSP_BIC_HP physics list provided an overall adequate description of the physics involved in hadron therapy, including proton and carbon ion therapy. New tests should be included in the next stage of the project to extend the benchmarking to other physical quantities and application scenarios of interest for medical physics. CONCLUSION: The results presented and discussed in this paper will aid users in tailoring physics lists to their particular application.

With the advent of the Heliophysics/Geospace System Observatory (H/GSO), a complement of multi-spacecraft missions and ground-based observatories to study the space environment, data retrieval, analysis, and visualization of space physics data can be daunting. The Space Physics Environment Data Analysis System (SPEDAS), a grass-roots software development platform (www.spedas.org), is now officially supported by NASA Heliophysics as part of its data environment infrastructure. It serves more than a dozen space missions and ground observatories and can integrate the full complement of past and upcoming space physics missions with minimal resources, following clear, simple, and well-proven guidelines. Free, modular and configurable to the needs of individual missions, it works in both command-line (ideal for experienced users) and Graphical User Interface (GUI) mode (reducing the learning curve for first-time users). Both options have "crib-sheets," user-command sequences in ASCII format that can facilitate record-and-repeat actions, especially for complex operations and plotting. Crib-sheets enhance scientific interactions, as users can move rapidly and accurately from exchanges of technical information on data processing to efficient discussions regarding data interpretation and science. SPEDAS can readily query and ingest all International Solar Terrestrial Physics (ISTP)-compatible products from the Space Physics Data Facility (SPDF), enabling access to a vast collection of historic and current mission data. The planned incorporation of Heliophysics Application Programmer's Interface (HAPI) standards will facilitate data ingestion from distributed datasets that adhere to these standards. Although SPEDAS is currently Interactive Data Language (IDL)-based (and interfaces to Java-based tools such as Autoplot), efforts are under-way to expand it further to work with python (first as an interface tool and potentially even receiving an under-the-hood replacement). We review the SPEDAS development history, goals, and current implementation. We explain its "modes of use" with examples geared for users and outline its technical implementation and requirements with software developers in mind. We also describe SPEDAS personnel and software management, interfaces with other organizations, resources and support structure available to the community, and future development plans. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1007/s11214-018-0576-4) contains supplementary material, which is available to authorized users.

Monte Carlo techniques have become ubiquitous in medical physics over the last 50 years with a doubling of papers on the subject every 5 years between the first PMB paper in 1967 and 2000 when the numbers levelled off. While recognizing the many other roles that Monte Carlo techniques have played in medical physics, this review emphasizes techniques for electron-photon transport simulations. The broad range of codes available is mentioned but there is special emphasis on the EGS4/EGSnrc code system which the author has helped develop for 25 years. The importance of the 1987 Erice Summer School on Monte Carlo techniques is highlighted. As an illustrative example of the role Monte Carlo techniques have played, the history of the correction for wall attenuation and scatter in an ion chamber is presented as it demonstrates the interplay between a specific problem and the development of tools to solve the problem which in turn leads to applications in other areas.

The consolidation of the scientific publishing industry has been the topic of much debate within and outside the scientific community, especially in relation to major publishers' high profit margins. However, the share of scientific output published in the journals of these major publishers, as well as its evolution over time and across various disciplines, has not yet been analyzed. This paper provides such analysis, based on 45 million documents indexed in the Web of Science over the period 1973-2013. It shows that in both natural and medical sciences (NMS) and social sciences and humanities (SSH), Reed-Elsevier, Wiley-Blackwell, Springer, and Taylor & Francis increased their share of the published output, especially since the advent of the digital era (mid-1990s). Combined, the top five most prolific publishers account for more than 50% of all papers published in 2013. Disciplines of the social sciences have the highest level of concentration (70% of papers from the top five publishers), while the humanities have remained relatively independent (20% from top five publishers). NMS disciplines are in between, mainly because of the strength of their scientific societies, such as the ACS in chemistry or APS in physics. The paper also examines the migration of journals between small and big publishing houses and explores the effect of publisher change on citation impact. It concludes with a discussion on the economics of scholarly publishing.

The production of metal parts via laser powder bed fusion additive manufacturing is growing exponentially. However, the transition of this technology from production of prototypes to production of critical parts is hindered by a lack of confidence in the quality of the part. Confidence can be established via a fundamental understanding of the physics of the process. It is generally accepted that this understanding will be increasingly achieved through modeling and simulation. However, there are significant physics, computational, and materials challenges stemming from the broad range of length and time scales and temperature ranges associated with the process. In this paper, we review the current state of the art and describe the challenges that need to be met to achieve the desired fundamental understanding of the physics of the process.

July 01 1996 Dynamic Patterns: The Self-Organization of Brain and Behavior In Special Collection: CogNet J. A. ScottKelso, Cambridge, MA: The MIT Press, 1995, Hardbound, 334 pages, $49.95. ISBN 0-262-11200-0 A. J. van Opstal A. J. van Opstal Department of Medical Physics and Biophysics, University of Nijmegen, Nijmegen, The Netherlands. Search for other works by this author on: This Site Google Scholar Author and Article Information A. J. van Opstal Department of Medical Physics and Biophysics, University of Nijmegen, Nijmegen, The Netherlands. Online ISSN: 1530-8898 Print ISSN: 0898-929X © 1996 by the Massachusetts Institute of Technology1996 Journal of Cognitive Neuroscience (1996) 8 (4): 385–386. https://doi.org/10.1162/jocn.1996.8.4.385 Cite Icon Cite Permissions Share Icon Share Facebook Twitter LinkedIn MailTo Views Icon Views Article contents Figures & tables Video Audio Supplementary Data Peer Review Search Site Citation A. J. van Opstal; Dynamic Patterns: The Self-Organization of Brain and Behavior. J Cogn Neurosci 1996; 8 (4): 385–386. doi: https://doi.org/10.1162/jocn.1996.8.4.385 Download citation file: Ris (Zotero) Reference Manager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentAll JournalsJournal of Cognitive Neuroscience Search Advanced Search This content is only available as a PDF. © 1996 by the Massachusetts Institute of Technology1996 Article PDF first page preview Close Modal You do not currently have access to this content.

Studies involving Monte Carlo simulations are common in both diagnostic and therapy medical physics research, as well as other fields of basic and applied science. As with all experimental studies, the conditions and parameters used for Monte Carlo simulations impact their scope, validity, limitations, and generalizability. Unfortunately, many published peer-reviewed articles involving Monte Carlo simulations do not provide the level of detail needed for the reader to be able to properly assess the quality of the simulations. The American Association of Physicists in Medicine Task Group #268 developed guidelines to improve reporting of Monte Carlo studies in medical physics research. By following these guidelines, manuscripts submitted for peer-review will include a level of relevant detail that will increase the transparency, the ability to reproduce results, and the overall scientific value of these studies. The guidelines include a checklist of the items that should be included in the Methods, Results, and Discussion sections of manuscripts submitted for peer-review. These guidelines do not attempt to replace the journal reviewer, but rather to be a tool during the writing and review process. Given the varied nature of Monte Carlo studies, it is up to the authors and the reviewers to use this checklist appropriately, being conscious of how the different items apply to each particular scenario. It is envisioned that this list will be useful both for authors and for reviewers, to help ensure the adequate description of Monte Carlo studies in the medical physics literature.

Graves' orbitopathy (GO) is the main extrathyroidal manifestation of Graves' disease (GD). Choice of treatment should be based on the assessment of clinical activity and severity of GO. Early referral to specialized centers is fundamental for most patients with GO. Risk factors include smoking, thyroid dysfunction, high serum level of thyrotropin receptor antibodies, radioactive iodine (RAI) treatment, and hypercholesterolemia. In mild and active GO, control of risk factors, local treatments, and selenium (selenium-deficient areas) are usually sufficient; if RAI treatment is selected to manage GD, low-dose oral prednisone prophylaxis is needed, especially if risk factors coexist. For both active moderate-to-severe and sight-threatening GO, antithyroid drugs are preferred when managing Graves' hyperthyroidism. In moderate-to-severe and active GO i.v. glucocorticoids are more effective and better tolerated than oral glucocorticoids. Based on current evidence and efficacy/safety profile, costs and reimbursement, drug availability, long-term effectiveness, and patient choice after extensive counseling, a combination of i.v. methylprednisolone and mycophenolate sodium is recommended as first-line treatment. A cumulative dose of 4.5 g of i.v. methylprednisolone in 12 weekly infusions is the optimal regimen. Alternatively, higher cumulative doses not exceeding 8 g can be used as monotherapy in most severe cases and constant/inconstant diplopia. Second-line treatments for moderate-to-severe and active GO include (a) the second course of i.v. methylprednisolone (7.5 g) subsequent to careful ophthalmic and biochemical evaluation, (b) oral prednisone/prednisolone combined with either cyclosporine or azathioprine; (c) orbital radiotherapy combined with oral or i.v. glucocorticoids, (d) teprotumumab; (e) rituximab and (f) tocilizumab. Sight-threatening GO is treated with several high single doses of i.v. methylprednisolone per week and, if unresponsive, with urgent orbital decompression. Rehabilitative surgery (orbital decompression, squint, and eyelid surgery) is indicated for inactive residual GO manifestations.

This paper reviews the ecosystem of GATE, an open-source Monte Carlo toolkit for medical physics. Based on the shoulders of Geant4, the principal modules (geometry, physics, scorers) are described with brief descriptions of some key concepts (Volume, Actors, Digitizer). The main source code repositories are detailed together with the automated compilation and tests processes (Continuous Integration). We then described how the OpenGATE collaboration managed the collaborative development of about one hundred developers during almost 20 years. The impact of GATE on medical physics and cancer research is then summarized, and examples of a few key applications are given. Finally, future development perspectives are indicated.

As one of the most popular approaches in artificial intelligence, deep learning (DL) has attracted a lot of attention in the medical physics field over the past few years. The goals of this topical review article are twofold. First, we will provide an overview of the method to medical physics researchers interested in DL to help them start the endeavor. Second, we will give in-depth discussions on the DL technology to make researchers aware of its potential challenges and possible solutions. As such, we divide the article into two major parts. The first part introduces general concepts and principles of DL and summarizes major research resources, such as computational tools and databases. The second part discusses challenges faced by DL, present available methods to mitigate some of these challenges, as well as our recommendations.

Photodynamic therapy (PDT) uses light-activated drugs to treat diseases ranging from cancer to age-related macular degeneration and antibiotic-resistant infections. This paper reviews the current status of PDT with an emphasis on the contributions of physics, biophysics and technology, and the challenges remaining in the optimization and adoption of this treatment modality. A theme of the review is the complexity of PDT dosimetry due to the dynamic nature of the three essential components -- light, photosensitizer and oxygen. Considerable progress has been made in understanding the problem and in developing instruments to measure all three, so that optimization of individual PDT treatments is becoming a feasible target. The final section of the review introduces some new frontiers of research including low dose rate (metronomic) PDT, two-photon PDT, activatable PDT molecular beacons and nanoparticle-based PDT.

Three-dimensional (3D) printing refers to a number of manufacturing technologies that generate a physical model from digital information. Medical 3D printing was once an ambitious pipe dream. However, time and investment made it real. Nowadays, the 3D printing technology represents a big opportunity to help pharmaceutical and medical companies to create more specific drugs, enabling a rapid production of medical implants, and changing the way that doctors and surgeons plan procedures. Patient-specific 3D-printed anatomical models are becoming increasingly useful tools in today's practice of precision medicine and for personalized treatments. In the future, 3D-printed implantable organs will probably be available, reducing the waiting lists and increasing the number of lives saved. Additive manufacturing for healthcare is still very much a work in progress, but it is already applied in many different ways in medical field that, already reeling under immense pressure with regards to optimal performance and reduced costs, will stand to gain unprecedented benefits from this good-as-gold technology. The goal of this analysis is to demonstrate by a deep research of the 3D-printing applications in medical field the usefulness and drawbacks and how powerful technology it is.

For a long time the discovery of new scintillators has been more serendipitous than driven by a deep understanding of the mechanisms at the origin of the scintillation process. This situation has dramatically changed since the 1990's with an increased demand for scintillators of better performance for large particle physics experiments as well as for medical imaging. It is now possible to design a scintillator for a specific purpose. The bandgap can be adjusted, the traps energy levels and their concentration can be finely tuned and their influence can be damped or on the contrary enhanced by specific doping for an optimization of the performance of the scintillator. Several examples are given in this paper of such crystal engineering attempts to improve the performance of crystal scintillators used in medical imaging devices. An attention is also given to spectacular progress in crystal production technologies, which open new perspectives for large scale and cost effective crystal production with consistent quality.