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Sample records for energy varian medical

  1. Assessment of beam stability of high energy and low energy Varian medical linear accelerators

    International Nuclear Information System (INIS)

    Jayesh, K.; Mohan, R.; Joshi, R.C.; Ganesh, T.; Hegazy, M.; Oubaye, A.J.; AI Idrisi, Maha

    2008-01-01

    An accurate measurement of the dose delivered to the tumor in external beam radiotherapy is one of the primary responsibilities of a medical physicist. In general, such measurements have been based on the application of a dosimetry protocol and quality assurance procedures. Clinically one must be able to assess the beam quality, flatness and symmetry and variation in the output on daily basis. Flatness and symmetry are the main parameters for determining the pattern of a photon and electron beam produced by linear accelerators. The quality assurance in routine clinical practice of radiotherapy and consequently the treatment-outcome depends definitely on the physical parameters of treatment-delivery. Several recommendations from national and international associations are reported to define the limits for the beam parameters. The review of literature and various reports on quality assurance in radiotherapy show that for flatness, symmetry and output constancy the optimal level of deviation should be within ±3%

  2. Experimental validation of neutron activation simulation of a varian medical linear accelerator.

    Science.gov (United States)

    Morato, S; Juste, B; Miro, R; Verdu, G; Diez, S

    2016-08-01

    This work presents a Monte Carlo simulation using the last version of MCNP, v. 6.1.1, of a Varian CLinAc emitting a 15MeV photon beam. The main objective of the work is to estimate the photoneutron production and activated products inside the medical linear accelerator head. To that, the Varian LinAc head was modelled in detail using the manufacturer information, and the model was generated with a CAD software and exported as a mesh to be included in the particle transport simulation. The model includes the transport of photoneutrons generated by primary photons and the (n, γ) reactions which can result in activation products. The validation of this study was done using experimental measures. Activation products have been identified by in situ gamma spectroscopy placed at the jaws exit of the LinAc shortly after termination of a high energy photon beam irradiation. Comparison between experimental and simulation results shows good agreement.

  3. Morphological plasticity in the tropical sponge Anthosigmella varians: responses to predators and wave energy.

    Science.gov (United States)

    Hill, Malcolm S; Hill, April L

    2002-02-01

    The goal of the research presented here was to examine phenotypic plasticity exhibited by three morphotypes of the common Caribbean sponge Anthosigmella varians (Duchassaing & Michelotti). We were interested in examining the biotic (and, to a lesser extent, abiotic) factors responsible for branch production in this species. We also tested the hypothesis that the skeleton may serve an antipredator function in this sponge, focusing on vertebrate fish predators (i.e., angelfish) in this work. In transplant and caging experiments, unprotected forma varians replicates were immediately consumed by angelfish, while caged replicates persisted on the reef for several months. These findings support the hypothesis that predators (and not wave energy) restrict forma varians to lagoonal habitats. Branch production was not observed in A. varians forma incrustans when sponges were protected from predators or placed in predator-free, low-wave-energy environments. It is not clear from our work whether forma incrustans is capable of producing branches (i.e., whether branch production is a plastic trait in this morph). Additional field experiments demonstrated that A. varians forma varians increased spicule concentrations, compared to uninjured sponges, in response to artificial predation events, and A. varians forma rigida reduced spicule concentrations, compared to uncaged controls, when protected from predators. These findings indicate that spicule concentration is a plastic morphological trait that can be induced by damage, and that A. varians may be able to reduce spicule concentrations when environmental conditions change (e.g., in the absence of predators). The potential significance of inducible defenses and structural anti-predator defenses in sponges is discussed in relation to recent work on sponge chemical defenses.

  4. High energy medical accelerators

    International Nuclear Information System (INIS)

    Mandrillon, P.

    1990-01-01

    The treatment of tumours with charged particles, ranging from protons to 'light ions' (carbon, oxygen, neon), has many advantages, but up to now has been little used because of the absence of facilities. After the successful pioneering work carried out with accelerators built for physics research, machines dedicated to this new radiotherapy are planned or already in construction. These high energy medical accelerators are presented in this paper. (author) 15 refs.; 14 figs.; 8 tabs

  5. Collateral patient doses in the Varian 21iX radiotherapy Linac

    International Nuclear Information System (INIS)

    Barquero, R.; Castillo, A. del

    2008-01-01

    Full text: The radiotherapy aim is to irradiate the patient tumor cells while the doses in healthy tissue remains as low as possible. Nevertheless, when high photon energy accelerators are used, collateral undesired photon and neutron doses are always implied during the treatments and became more important with the new accelerators and techniques as IMRT. To assess secondary cancer risk outside the treatment volume as a long-term medical consequence of treatments, the total doses received by each patient outside the primary field during his treatment must be estimated. To achieve this purpose photon and neutron dose equivalents Hp(10) and H*(10) has been measured in a new Varian 21iX with maximum photon energy of 15 MV placed recently in our radiotherapy department. Three devices: 1) a neutron dose rate meter BERTHOLD LB 4111 calibrated recently in the German PTB laboratory, 2) a calibrated environmental pressurized photon ionization chamber (IC) VICTOREEN 450-PI n/s 1020, and 3) a calibrated personal electronic photon dosimeter GAMMACOM 4200M, were placed above the treatment couch outside the primary field while the Varian 21iX reference test were done. In particular the photon and neutron doses in the couch were measured while a water phantom was irradiated during automatic beam data acquisition for a 15 MV beam. A complete set of measurements changing field size are made. These 15 MV results are compared with data measured previously by thermoluminescence and bubble dosimeters in the same facility for an Elekta Precise and a Siemens KDS both with maximum photon energy of 18 MV. From this the benefits in the patient collateral doses of decreasing the maximum treatment photon energy are discussed. The patient doses obtained in the Varian 21iX had values that go from 80 to 800 uSv per treatment Gray. As the Varian 21iX therapy Linac is operated in pulsed mode with short pulse length the discussion of the results includes: 1. The correction of dead time in the GM

  6. Preliminary Determination of Activation Products for a Varian Truebeam Linear Accelerator.

    Science.gov (United States)

    Waller, Edward; Ram, Rohan; Steadman, Ian

    2017-09-01

    Medical linear accelerators used to treat various forms of cancers are operated at a number of different energies. A by-product of the high-energy photons produced by accelerators is activation of components within the machine itself and its surrounding bunker. The activation products pose radiological and regulatory challenges during the operation of the accelerator as well as when it is time for final decommissioning. The Varian TrueBeam is a new state-of-the-art linear accelerator now operating in the Canadian market. There is currently limited information on the production of its activation products and the resulting impacts on operation and decommissioning. In this paper, activation products in the Varian TrueBeam accelerator are experimentally determined by performing gamma spectroscopy using a portable high purity germanium detector. A total of 10 isotopes are identified for the conditions tested, which include Na, Al, Mn, Ni, Cu, Cu, Br, Sb, Sb, W. The half-lives of these isotopes range from 2.3 min to 60.2 d. These preliminary results indicate that a decommissioning case similar to other radiotherapy accelerators can be made.

  7. Neutron contamination of Varian Clinac iX 10 MV photon beam using Monte Carlo simulation

    International Nuclear Information System (INIS)

    Yani, S; Haryanto, F; Arif, I; Tursinah, R; Rhani, M F; Soh, R C X

    2016-01-01

    High energy medical accelerators are commonly used in radiotherapy to increase the effectiveness of treatments. As we know neutrons can be emitted from a medical accelerator if there is an incident of X-ray that hits any of its materials. This issue becomes a point of view of many researchers. The neutron contamination has caused many problems such as image resolution and radiation protection for patients and radio oncologists. This study concerns the simulation of neutron contamination emitted from Varian Clinac iX 10 MV using Monte Carlo code system. As neutron production process is very complex, Monte Carlo simulation with MCNPX code system was carried out to study this contamination. The design of this medical accelerator was modelled based on the actual materials and geometry. The maximum energy of photons and neutron in the scoring plane was 10.5 and 2.239 MeV, respectively. The number and energy of the particles produced depend on the depth and distance from beam axis. From these results, it is pointed out that the neutron produced by linac 10 MV photon beam in a typical treatment is not negligible. (paper)

  8. Kocuria varians infection associated with brain abscess: A case report

    Directory of Open Access Journals (Sweden)

    Tsai Tai-Hsin

    2010-04-01

    Full Text Available Abstract Background Kocuria, established by Stackebrandt et al., previously was classified into Micrococcus. Only two species, K. rosea and K. kristinae are reported to be associated as pathogenic and found with catheter-related bacteremia and acute cholecystitis. Case presentation We herein report the first case of brain abscess caused by Kocuria varians, a gram-positive microorganism, in a 52-year-old man. Hematogenous spread is the probable pathogenesis. Conclusions This report presents a case of Kocuria varians brain abscess successfully treated with surgical excision combined with antimicrobial therapy. In addition, Vitek 2 system has been used to identify and differentiate between coagulase-negative staphylococcus.

  9. Kocuria varians infection associated with brain abscess: a case report.

    Science.gov (United States)

    Tsai, Cheng-Yu; Su, Shou-hsin; Cheng, Yu-Hsin; Chou, Yu-lin; Tsai, Tai-Hsin; Lieu, Ann-Shung

    2010-04-27

    Kocuria, established by Stackebrandt et al., previously was classified into Micrococcus. Only two species, K. rosea and K. kristinae are reported to be associated as pathogenic and found with catheter-related bacteremia and acute cholecystitis. We herein report the first case of brain abscess caused by Kocuria varians, a gram-positive microorganism, in a 52-year-old man. Hematogenous spread is the probable pathogenesis. This report presents a case of Kocuria varians brain abscess successfully treated with surgical excision combined with antimicrobial therapy. In addition, Vitek 2 system has been used to identify and differentiate between coagulase-negative staphylococcus.

  10. SU-E-T-775: Use of Electronic Portal Imaging Device (EPID) for Quality Assurance (QA) of Electron Beams On Varian Truebeam System

    Energy Technology Data Exchange (ETDEWEB)

    Cai, B; Yaddanapudi, S; Sun, B; Li, H; Noel, C; Mutic, S; Goddu, S [Department of Radiation Oncology, Washington University in St Louis, St. Louis, MO (United States)

    2015-06-15

    Purpose: In a previous study we have demonstrated the feasibility of using EPID to QA electron beam parameters on a single Varian TrueBeam LINAC. This study aims to provide further investigation on (1) reproducibility of using EPID to detect electron beam energy changes on multiple machines and (2) evaluation of appropriate calibration methods to compare results from different EPIDs. Methods: Ad-hoc mode electron beam images were acquired in developer mode with XML code. Electron beam data were collected on a total of six machines from four institutions. A custom-designed double-wedge phantom was placed on the EPID detector. Two calibration methods - Pixel Sensitivity Map (PSM) and Large Source-to-Imager Distance Flood Field (LSID-FF) - were used. To test the sensitivity of EPID in detecting energy drifts, Bending Magnet Current (BMC) was detuned to invoke energy changes corresponding to ∼±1.5 mm change in R50% of PDD on two machines from two institutions. Percent depth ionization (PDI) curves were then analyzed and compared with the respective baseline images using LSID-FF calibration. For reproducibility testing, open field EPID images and images with a standard testing phantom were collected on multiple machines. Images with and without PSM correction for same energies on different machines were overlaid and compared. Results: Two pixel shifts were observed in PDI curve when energy changes exceeded the TG142 tolerance. PSM showed the potential to correct the differences in pixel response of different imagers. With PSM correction, the histogram of images differences obtained from different machines showed narrower distributions than those images without PSM correction. Conclusion: EPID is sensitive for electron energy changes and the results are reproducible on different machines. When overlaying images from different machines, PSM showed the ability to partially eliminate the intrinsic variation of various imagers. Research Funding from Varian Medical Systems

  11. Analysis of output trends from Varian 2100C/D and 600C/D accelerators

    International Nuclear Information System (INIS)

    Grattan, M W D; Hounsell, A R

    2011-01-01

    Analysis of Varian linear accelerator output trends is reported. Two groups, consisting of four matched Varian 2100C/D and four matched Varian 600C/D accelerators, with different designs of monitor chamber, have been investigated and the data acquired from regular calibrated ion chamber/electrometer measurements of the output performance of the eight accelerators analysed. The trend of machine output with time, having removed the effect of adjusting the monitor chamber response, was compared on a monthly and annual basis for monitor chambers with ages ranging between 1 year and 7 years. The results indicate that the response is generally consistent within each set of accelerators with different monitor chamber designs. Those used in a Varian 600C/D machine result in a reduction in measured output over time, with an average monthly reduction of 0.35 ± 0.09% over the course of the first 4 years of use. The chambers used in a 2100C/D accelerator result in an increase in measured output over time, with an average monthly increase of 0.26 ± 0.09% over the course of the first 4 years of use. The output increase then reduces towards the end of this period of time, with the average monthly change falling to -0.03 ± 0.02% for the following 3 years. The output response trend was similar for all clinical energies used on the 2100C/D accelerators--6, 15 MV x-ray beams, and 4, 6, 9, 12, 16 and 20 MeV electron beams. By tracking these changes it has been possible to predict the response over time to allow appropriate adjustments in monitor chamber response to maintain a measured accelerator output within tolerance and give confidence in performance. It has also provided data to indicate the need for planned preventative intervention and indicate if the monitor chamber response is behaving as expected. (note)

  12. Medical applications of the nuclear energy

    International Nuclear Information System (INIS)

    Ugarte, Valentin E.

    2001-01-01

    The Nuclear Medicine School Foundation, in Mendoza (Argentina) was created in 1986 by the National Atomic Energy Commission (CNEA) and is supported by the Government of the Mendoza Province, the CNEA, and the National University of Cuyo. The main activities of the school are medical diagnosis using nuclear techniques and the training of physicians and technicians in nuclear medicine. Teletherapy and brachytherapy are also performed. The use of the PET is described in some detail

  13. TU-AB-BRC-05: Creation of a Monte Carlo TrueBeam Model by Reproducing Varian Phase Space Data

    International Nuclear Information System (INIS)

    O’Grady, K; Davis, S; Seuntjens, J

    2016-01-01

    Purpose: To create a Varian TrueBeam 6 MV FFF Monte Carlo model using BEAMnrc/EGSnrc that accurately reproduces the Varian representative dataset, followed by tuning the model’s source parameters to accurately reproduce in-house measurements. Methods: A BEAMnrc TrueBeam model for 6 MV FFF has been created by modifying a validated 6 MV Varian CL21EX model. Geometric dimensions and materials were adjusted in a trial and error approach to match the fluence and spectra of TrueBeam phase spaces output by the Varian VirtuaLinac. Once the model’s phase space matched Varian’s counterpart using the default source parameters, it was validated to match 10 × 10 cm"2 Varian representative data obtained with the IBA CC13. The source parameters were then tuned to match in-house 5 × 5 cm"2 PTW microDiamond measurements. All dose to water simulations included detector models to include the effects of volume averaging and the non-water equivalence of the chamber materials, allowing for more accurate source parameter selection. Results: The Varian phase space spectra and fluence were matched with excellent agreement. The in-house model’s PDD agreement with CC13 TrueBeam representative data was within 0.9% local percent difference beyond the first 3 mm. Profile agreement at 10 cm depth was within 0.9% local percent difference and 1.3 mm distance-to-agreement in the central axis and penumbra regions, respectively. Once the source parameters were tuned, PDD agreement with microDiamond measurements was within 0.9% local percent difference beyond 2 mm. The microDiamond profile agreement at 10 cm depth was within 0.6% local percent difference and 0.4 mm distance-to-agreement in the central axis and penumbra regions, respectively. Conclusion: An accurate in-house Monte Carlo model of the Varian TrueBeam was achieved independently of the Varian phase space solution and was tuned to in-house measurements. KO acknowledges partial support by the CREATE Medical Physics Research

  14. The Varian MAT-250 mass spectrometer. Steady isotopes laboratory

    International Nuclear Information System (INIS)

    Hernandez M, V.; Tavera D, M.L.

    1997-01-01

    This work treats over the performance and applications of the Varian Mat-250 mass spectrometer which is in the environmental isotope laboratory. It can be applied over topics such as: ions formation, acceleration and collimation, ions separation, ions detection, data transformation, sampling, δ notation. (Author)

  15. The Varian MAT-250 mass spectrometer. Steady isotopes laboratory; Espectrometro de masas Varian MAT-250. Laboratorio de isotopos estables

    Energy Technology Data Exchange (ETDEWEB)

    Hernandez M, V.; Tavera D, M.L. [Instituto Nacional de Investigaciones Nucleares, A.P. 18-1027, 11801 Mexico D.F. (Mexico)

    1997-07-01

    This work treats over the performance and applications of the Varian Mat-250 mass spectrometer which is in the environmental isotope laboratory. It can be applied over topics such as: ions formation, acceleration and collimation, ions separation, ions detection, data transformation, sampling, {delta} notation. (Author)

  16. Converting energy to medical progress [nuclear medicine

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-04-01

    For over 50 years the Office of Biological and Environmental Research (BER) of the United States Department of Energy (DOE) has been investing to advance environmental and biomedical knowledge connected to energy. The BER Medical Sciences program fosters research to develop beneficial applications of nuclear technologies for medical diagnosis and treatment of many diseases. Today, nuclear medicine helps millions of patients annually in the United States. Nearly every nuclear medicine scan or test used today was made possible by past BER-funded research on radiotracers, radiation detection devices, gamma cameras, PET and SPECT scanners, and computer science. The heart of biological research within BER has always been the pursuit of improved human health. The nuclear medicine of tomorrow will depend greatly on today's BER-supported research, particularly in the discovery of radiopharmaceuticals that seek specific molecular and genetic targets, the design of advanced scanners needed to create meaningful images with these future radiotracers, and the promise of new radiopharmaceutical treatments for cancers and genetic diseases.

  17. Converting energy to medical progress [nuclear medicine

    International Nuclear Information System (INIS)

    2001-01-01

    For over 50 years the Office of Biological and Environmental Research (BER) of the United States Department of Energy (DOE) has been investing to advance environmental and biomedical knowledge connected to energy. The BER Medical Sciences program fosters research to develop beneficial applications of nuclear technologies for medical diagnosis and treatment of many diseases. Today, nuclear medicine helps millions of patients annually in the United States. Nearly every nuclear medicine scan or test used today was made possible by past BER-funded research on radiotracers, radiation detection devices, gamma cameras, PET and SPECT scanners, and computer science. The heart of biological research within BER has always been the pursuit of improved human health. The nuclear medicine of tomorrow will depend greatly on today's BER-supported research, particularly in the discovery of radiopharmaceuticals that seek specific molecular and genetic targets, the design of advanced scanners needed to create meaningful images with these future radiotracers, and the promise of new radiopharmaceutical treatments for cancers and genetic diseases

  18. Halophilic Nuclease from a Moderately Halophilic Micrococcus varians

    Science.gov (United States)

    Kamekura, Masahiro; Onishi, Hiroshi

    1974-01-01

    The moderately halophilic bacterium Micrococcus varians, isolated from soy sauce mash, produced extracellular nuclease when cultivated aerobically in media containing 1 to 4 M NaCl or KCl. The enzyme, purified to an electrophoretically homogeneous state, had both ribonuclease and deoxyribonuclease activities. The nuclease had maximal activity in the presence of 2.9 M NaCl or 2.1 M KCl at 40 C. The enzymatic activity was lost by dialysis against low-salt buffer, whereas when the inactivated enzyme was dialyzed against 3.4 M NaCl buffer as much as 77% of the initial activity could be restored. Images PMID:4852218

  19. SU-E-T-362: Enhanced Dynamic Wedge Output Factors for Varian 2300CD and the Case for a Reference Database

    International Nuclear Information System (INIS)

    Njeh, C

    2015-01-01

    Purpose: Dose inhomogeneity in treatment planning can be compensated using physical wedges. Enhanced dynamic wedges (EDW) were introduced by Varian to overcome some of the short comings of physical wedges. The objectives of this study were to measure EDW output factors for 6 MV and 20 MV photon energies for a Varian 2300CD. Secondly to review the literature in terms of published enhanced dynamic wedge output factors (EDWOF) for different Varian models and thereby adding credence to the case of the validity of reference databases. Methods: The enhanced dynamic wedge output factors were measured for the Varian 2300CD for both 6 MV and 20 MV photon energies. Twelve papers with published EDWOF for different Varian Linac models were found in the literature. Results: The EDWOF for 6 MV varied from 0.980 for a 5×5 cm 10 degree wedge to 0.424 for 20×20 cm 60 degree wedge. Similarly for 20 MV, the EDWOF varied from 0.986 for 5×5 cm 10 degree wedge to 0.529 for 20×20 cm 60 degree wedge. EDWOF are highly dependent on field size. Comparing our results with the published mean, we found an excellent agreement for 6 MV EDWOF with the percentage differences ranging from 0.01% to 0.57% with a mean of 0.03%. The coefficient of variation of published EDWOF ranged from 0.17% to 0.85% and 0.1% to 0.9% for the for 6 MV and 18MV photon energies respectively. This paper provides the first published EDWOF for 20 MV photon energy. In addition, we have provided the first compendium of EDWOFs for different Varian linac models. Conclusion: The consistency of EDWOF across models and institution provide further support that, a standard data set of basic photon and electron dosimetry could be established, as a guide for future commissioning, beam modeling and quality assurance purposes

  20. Source to Skin Distance (SSD) Characteristics from Varian CX Linear Accelerator

    Science.gov (United States)

    Bahari Nurdin, Wira; Purnomo, Aji; Dewang, Syamsir

    2018-03-01

    This study aims to describe the characteristics of the source to skin distance (SSD) of Varian CX linear accelerator (LINAC) using the X-ray beam of 6 MV and 10 MV. The variation of the source to the SSD are 90, 100 and 110 cms; the depth of the water phantom used are 5, 10, 15, 20, and 25 cms, respectively. The depth of the water phantom was created for analysis of percentage depth dose (PDD) and profile dose. It can be concluded from the tests that from the measured SSD, SSD of 110 cm with the depth water phantom of 20-25 cm for energy beam of 6 MV and at all levels of depth for 10 MV energy corresponding tolerance limits to be used in clinical radiotherapy. For the SSD 90 and 100, the values beam symmetry and flatness obtained slightly beyond the limits of tolerance.

  1. Neutron dose measurements of Varian and Elekta linacs by TLD600 and TLD700 dosimeters and comparison with MCNP calculations.

    Science.gov (United States)

    Nedaie, Hassan Ali; Darestani, Hoda; Banaee, Nooshin; Shagholi, Negin; Mohammadi, Kheirollah; Shahvar, Arjang; Bayat, Esmaeel

    2014-01-01

    High-energy linacs produce secondary particles such as neutrons (photoneutron production). The neutrons have the important role during treatment with high energy photons in terms of protection and dose escalation. In this work, neutron dose equivalents of 18 MV Varian and Elekta accelerators are measured by thermoluminescent dosimeter (TLD) 600 and TLD700 detectors and compared with the Monte Carlo calculations. For neutron and photon dose discrimination, first TLDs were calibrated separately by gamma and neutron doses. Gamma calibration was carried out in two procedures; by standard 60Co source and by 18 MV linac photon beam. For neutron calibration by (241)Am-Be source, irradiations were performed in several different time intervals. The Varian and Elekta linac heads and the phantom were simulated by the MCNPX code (v. 2.5). Neutron dose equivalent was calculated in the central axis, on the phantom surface and depths of 1, 2, 3.3, 4, 5, and 6 cm. The maximum photoneutron dose equivalents which calculated by the MCNPX code were 7.06 and 2.37 mSv.Gy(-1) for Varian and Elekta accelerators, respectively, in comparison with 50 and 44 mSv.Gy(-1) achieved by TLDs. All the results showed more photoneutron production in Varian accelerator compared to Elekta. According to the results, it seems that TLD600 and TLD700 pairs are not suitable dosimeters for neutron dosimetry inside the linac field due to high photon flux, while MCNPX code is an appropriate alternative for studying photoneutron production.

  2. Energy functionals for medical image segmentation: choices and consequences

    OpenAIRE

    McIntosh, Christopher

    2011-01-01

    Medical imaging continues to permeate the practice of medicine, but automated yet accurate segmentation and labeling of anatomical structures continues to be a major obstacle to computerized medical image analysis. Though there exists numerous approaches for medical image segmentation, one in particular has gained increasing popularity: energy minimization-based techniques, and the large set of methods encompassed therein. With these techniques an energy function must be chosen, segmentations...

  3. Nuclear energy and its medical application

    International Nuclear Information System (INIS)

    Jain, S.K.

    2010-01-01

    Ionising radiation is used in radiotherapy to treat cancer and to sterilise medical equipment because it destroys cells. Radioactive tracers are used in nuclear medicine because the ionising radiation it emits is easy to detect. There are three main uses of ionising radiation in medicine: treatment, diagnosis and sterilisation. Radiotherapy is used to treat cancers by irradiating them with ionising radiation. Radioactive tracers are used to diagnose and investigate several medical conditions. Ionising radiation is used to sterilise medical equipment as it kills germs and/or bacteria

  4. [Porting Radiotherapy Software of Varian to Cloud Platform].

    Science.gov (United States)

    Zou, Lian; Zhang, Weisha; Liu, Xiangxiang; Xie, Zhao; Xie, Yaoqin

    2017-09-30

    To develop a low-cost private cloud platform of radiotherapy software. First, a private cloud platform which was based on OpenStack and the virtual GPU hardware was builded. Then on the private cloud platform, all the Varian radiotherapy software modules were installed to the virtual machine, and the corresponding function configuration was completed. Finally the software on the cloud was able to be accessed by virtual desktop client. The function test results of the cloud workstation show that a cloud workstation is equivalent to an isolated physical workstation, and any clients on the LAN can use the cloud workstation smoothly. The cloud platform transplantation in this study is economical and practical. The project not only improves the utilization rates of radiotherapy software, but also makes it possible that the cloud computing technology can expand its applications to the field of radiation oncology.

  5. Monte Carlo simulation of the Varian Clinac 600C accelerator using dynamic wedges; Simulacao Monte Carlo do acelerador Varian Clinac 600C utilizando cunhas dinamicas

    Energy Technology Data Exchange (ETDEWEB)

    Moreno, S. [Universidade da Beira Interior (UBI), Covilha (Portugal); Chaves, A.; Lopes, M.C. [Instituto Portugues de Oncologia Doutor Francisco Gentil (IPO), Coimbra (Portugal); Peralta, L. [Laboratorio de Instrumentacao e Fisica Experimental de Particulas (LIP), Lisboa (Portugal)]|[Universidade de Lisboa (Portugal). Faculdade de Ciencias

    2004-07-01

    The advent of linear accelerators (linac) with computer-controlled dynamic collimation systems and functional and anatomical imaging techniques allowed a more exact delimitation and localisation of the target volume. These advanced treatment techniques inevitably increase the complexity level of dose calculation because of the introduction of the temporal variable. On account of this, it is mandatory the usage of more accurate modelling techniques of the collimator components, as it is the case of Monte Carlo (MC) simulation, which has created an enormous interest in research and clinical practice. Because the patients bodies are not homogenous nor are their body surfaces plane and regular, the dose distribution may differ significantly from the standard distribution from the linac calibration. It is in the treatment planning systems, which include algorithms that are usually measured in homogeneous water phantoms specific for each correction that the dose distributions from each case are obtained. In a real treatment, exception made to superficial lesions, two or more radiation fields are used in order to obtain the recommended dose distributions. The simplest arrangement is made from two parallel and opposed fields that originate a homogeneous dose distribution in almost all the irradiated volume. The available resources are, for example, different types of energies and of radiation, the application of bolus, the protection of healthy structures, the usage of wedged filters and the application of dynamic wedges. A virtual or dynamic wedge, modelled through the movement of one of the jaws, when compared with a set of physical wedges offers an alternative calculation method of an arbitrary number of wedged fields, instead of the four traditional fields of 15 deg, 30 deg, 45 deg and 60 deg angle and obtained with physical wedges. The goal of this work consists in the study of the application of dynamic wedges in tailoring the radiation field by the Varian Clinac 600

  6. SU-F-T-66: Characteristics of Electron Beams From Varian Trubeam

    International Nuclear Information System (INIS)

    Dimofte, A; Kennedy, C; Zhu, T

    2016-01-01

    Purpose: The purpose of this study was to compare the electron beam data between Truebeam and 2300ix Varian accelerators for percent depth dose for broad beam and small circular cutouts, cone factors, head scatter factor as a function of cone size and SSD, phantom scatter factor, blocking factor, distance factor and virtual source position. Methods: Measurements were performed for Truebeam and 2300ix Varian accelerators. The main energies used were: 6, 9, 12, 16 and 20 MeV. PDD was measured at SSD = 100 cm for open beam and small circular cutouts (r = 0.5, 1.0, 1.5, 2.0, 3.0, 4.0 and 6.6cm) for different energies. Measurements to determine the head scatter factor (H) were done as a function of radius for six representative energies and five cone sizes (6, 10, 15, 20 and 25cm2). The phantom scatter factor (PSF) is defined as the ratio of blocking factor in water at reference depth and head scatter factor in air. PSF was measured as a function of radius and electron energy. Distance factor was measured for all energies and cones for three SSD’s (100, 110 and 120cm). Results: The percent depth dose (PDD) was measured for small cutouts of radius r = 0.5, 1.0, 1.5, 2.0, 3.0, 4.0, 5.0 and 5.6cm. Blocking factor (BF) was measured for Truebeam and 2300ix accelerators, for different circular cutouts and energies for a 10×10 cone. Cone factors were compared between the two accelerators for different energies and applicator sizes. Conclusion: Cone factors measured for the two accelerator types differ by up to 5% for the largest applicator size. Blocking factors differs by up to 3%, with the largest variation for the smallest field size (0.5cm). Distance factor for different SSD’s differ by up to 4.5%.

  7. SU-F-T-66: Characteristics of Electron Beams From Varian Trubeam

    Energy Technology Data Exchange (ETDEWEB)

    Dimofte, A; Kennedy, C; Zhu, T [University Pennsylvania, Philadelphia, PA (United States)

    2016-06-15

    Purpose: The purpose of this study was to compare the electron beam data between Truebeam and 2300ix Varian accelerators for percent depth dose for broad beam and small circular cutouts, cone factors, head scatter factor as a function of cone size and SSD, phantom scatter factor, blocking factor, distance factor and virtual source position. Methods: Measurements were performed for Truebeam and 2300ix Varian accelerators. The main energies used were: 6, 9, 12, 16 and 20 MeV. PDD was measured at SSD = 100 cm for open beam and small circular cutouts (r = 0.5, 1.0, 1.5, 2.0, 3.0, 4.0 and 6.6cm) for different energies. Measurements to determine the head scatter factor (H) were done as a function of radius for six representative energies and five cone sizes (6, 10, 15, 20 and 25cm2). The phantom scatter factor (PSF) is defined as the ratio of blocking factor in water at reference depth and head scatter factor in air. PSF was measured as a function of radius and electron energy. Distance factor was measured for all energies and cones for three SSD’s (100, 110 and 120cm). Results: The percent depth dose (PDD) was measured for small cutouts of radius r = 0.5, 1.0, 1.5, 2.0, 3.0, 4.0, 5.0 and 5.6cm. Blocking factor (BF) was measured for Truebeam and 2300ix accelerators, for different circular cutouts and energies for a 10×10 cone. Cone factors were compared between the two accelerators for different energies and applicator sizes. Conclusion: Cone factors measured for the two accelerator types differ by up to 5% for the largest applicator size. Blocking factors differs by up to 3%, with the largest variation for the smallest field size (0.5cm). Distance factor for different SSD’s differ by up to 4.5%.

  8. Out‐of‐field doses and neutron dose equivalents for electron beams from modern Varian and Elekta linear accelerators

    Science.gov (United States)

    Cardenas, Carlos E.; Nitsch, Paige L.; Kudchadker, Rajat J.; Howell, Rebecca M.

    2016-01-01

    Out‐of‐field doses from radiotherapy can cause harmful side effects or eventually lead to secondary cancers. Scattered doses outside the applicator field, neutron source strength values, and neutron dose equivalents have not been broadly investigated for high‐energy electron beams. To better understand the extent of these exposures, we measured out‐of‐field dose characteristics of electron applicators for high‐energy electron beams on two Varian 21iXs, a Varian TrueBeam, and an Elekta Versa HD operating at various energy levels. Out‐of‐field dose profiles and percent depth‐dose curves were measured in a Wellhofer water phantom using a Farmer ion chamber. Neutron dose was assessed using a combination of moderator buckets and gold activation foils placed on the treatment couch at various locations in the patient plane on both the Varian 21iX and Elekta Versa HD linear accelerators. Our findings showed that out‐of‐field electron doses were highest for the highest electron energies. These doses typically decreased with increasing distance from the field edge but showed substantial increases over some distance ranges. The Elekta linear accelerator had higher electron out‐of‐field doses than the Varian units examined, and the Elekta dose profiles exhibited a second dose peak about 20 to 30 cm from central‐axis, which was found to be higher than typical out‐of‐field doses from photon beams. Electron doses decreased sharply with depth before becoming nearly constant; the dose was found to decrease to a depth of approximately E(MeV)/4 in cm. With respect to neutron dosimetry, Q values and neutron dose equivalents increased with electron beam energy. Neutron contamination from electron beams was found to be much lower than that from photon beams. Even though the neutron dose equivalent for electron beams represented a small portion of neutron doses observed under photon beams, neutron doses from electron beams may need to be considered for

  9. Out-of-field doses and neutron dose equivalents for electron beams from modern Varian and Elekta linear accelerators.

    Science.gov (United States)

    Cardenas, Carlos E; Nitsch, Paige L; Kudchadker, Rajat J; Howell, Rebecca M; Kry, Stephen F

    2016-07-08

    Out-of-field doses from radiotherapy can cause harmful side effects or eventually lead to secondary cancers. Scattered doses outside the applicator field, neutron source strength values, and neutron dose equivalents have not been broadly investigated for high-energy electron beams. To better understand the extent of these exposures, we measured out-of-field dose characteristics of electron applicators for high-energy electron beams on two Varian 21iXs, a Varian TrueBeam, and an Elekta Versa HD operating at various energy levels. Out-of-field dose profiles and percent depth-dose curves were measured in a Wellhofer water phantom using a Farmer ion chamber. Neutron dose was assessed using a combination of moderator buckets and gold activation foils placed on the treatment couch at various locations in the patient plane on both the Varian 21iX and Elekta Versa HD linear accelerators. Our findings showed that out-of-field electron doses were highest for the highest electron energies. These doses typically decreased with increasing distance from the field edge but showed substantial increases over some distance ranges. The Elekta linear accelerator had higher electron out-of-field doses than the Varian units examined, and the Elekta dose profiles exhibited a second dose peak about 20 to 30 cm from central-axis, which was found to be higher than typical out-of-field doses from photon beams. Electron doses decreased sharply with depth before becoming nearly constant; the dose was found to decrease to a depth of approximately E(MeV)/4 in cm. With respect to neutron dosimetry, Q values and neutron dose equivalents increased with electron beam energy. Neutron contamination from electron beams was found to be much lower than that from photon beams. Even though the neutron dose equivalent for electron beams represented a small portion of neutron doses observed under photon beams, neutron doses from electron beams may need to be considered for special cases.

  10. Spirogyra varians mutant generated by high dose gamma-irradiation shows increased antioxidant properties

    International Nuclear Information System (INIS)

    Lee, Hak-Jyung; Yoon, Minchul; Sung, Nak-Yun; Choi, Jong-il

    2012-01-01

    The aim of this study was to evaluate the antioxidant properties of a Spirogyra varians mutant (Mut) produced by gamma irradiation. Methanol extracts were prepared from Spirogyra varians wild-type and Mut plants, and their antioxidant activities and total phenolic content (TPC) were determined. Antioxidant parameters, including the 2-diphenyl-1-picrylhydrazyl radical-scavenging activity and ferric-reducing/antioxidant power, were higher in the Mut extract. Moreover, the TPC level was higher (P<0.05) in the Mut methanol extract. Therefore, these results suggest that gamma irradiation-induced S. varians Mut has superior antioxidant properties. - Highlights: ► The antioxidative properties of a Spirogyra varians mutant produced by gamma-irradiation was investiated. ► The antioxidant activities and total phenolic content levels were higher in mutant strain. ► These results suggest that gamma-irradiation induced algae mutant with superior antioxidant properties.

  11. SU-E-T-403: Evaluation of the Beam Performance of a Varian TrueBeam Linear Accelerator Under External Device-Based Gated Delivery Conditions

    International Nuclear Information System (INIS)

    Kobulnicky, K; Pawlak, D; Purwar, A

    2015-01-01

    Purpose: To examine the beam performance of a Varian TrueBeam linear accelerator under external device-based gated delivery conditions. Methods: Six gating cycles were used to evaluate the gating performance of a standard production TrueBeam system that was not specially tuned in any way. The system was equipped with a factory installed external gating interface (EXGI). An in-house EXGI tester box was used to simulate the input gating signals. The gating cycles were selected based on long beam-on and short beam-off times, short beam-on and long beam-off times, or equal beam on and off times to check linac performance. The beam latencies were measured as the time difference between the logic high gating signal and the first or last target pulses with an oscilloscope. Tissue-Phantom Ratio, beam flatness, and dose distributions from 5 different plans were measured using the 6 different gating durations and the un-gated irradiation. A PTW 729 2-D array was used to compare 5 plans versus the un-gated delivery with a 1%/1mm gamma index passing criteria. Results: The beam latencies of the linac were based off of 20 samples for beam-on and beam-off, for each gating cycle. The average beam-on delays were measured to be between 57 and 66msec, with a maximum of 88 msec. The beam off latencies averaged between 19 and 26msec, with a maximum of 48 msec. TPR20,10 measurements showed beam energy stability within 0.5% of the un-gated delivery. Beam flatness was better than 2.5% for all gated cycles. All but two deliveries, the open field with 4 seconds on, 1 second off, and a five field IMRT plan with 0.5 seconds on, 2.5 seconds off, had >90% passing rate. Conclusion: TrueBeam demonstrates excellent beam stability with minimal beam latencies under external device-based gated operations. Dosimetric measurements show minimal variation in beam energy, flatness, and plan delivery. Authors are employees of Varian Medical Systems, Inc

  12. SU-E-T-403: Evaluation of the Beam Performance of a Varian TrueBeam Linear Accelerator Under External Device-Based Gated Delivery Conditions

    Energy Technology Data Exchange (ETDEWEB)

    Kobulnicky, K; Pawlak, D; Purwar, A [Varian Medical Systems, Inc., Palo Alto, CA (United States)

    2015-06-15

    Purpose: To examine the beam performance of a Varian TrueBeam linear accelerator under external device-based gated delivery conditions. Methods: Six gating cycles were used to evaluate the gating performance of a standard production TrueBeam system that was not specially tuned in any way. The system was equipped with a factory installed external gating interface (EXGI). An in-house EXGI tester box was used to simulate the input gating signals. The gating cycles were selected based on long beam-on and short beam-off times, short beam-on and long beam-off times, or equal beam on and off times to check linac performance. The beam latencies were measured as the time difference between the logic high gating signal and the first or last target pulses with an oscilloscope. Tissue-Phantom Ratio, beam flatness, and dose distributions from 5 different plans were measured using the 6 different gating durations and the un-gated irradiation. A PTW 729 2-D array was used to compare 5 plans versus the un-gated delivery with a 1%/1mm gamma index passing criteria. Results: The beam latencies of the linac were based off of 20 samples for beam-on and beam-off, for each gating cycle. The average beam-on delays were measured to be between 57 and 66msec, with a maximum of 88 msec. The beam off latencies averaged between 19 and 26msec, with a maximum of 48 msec. TPR20,10 measurements showed beam energy stability within 0.5% of the un-gated delivery. Beam flatness was better than 2.5% for all gated cycles. All but two deliveries, the open field with 4 seconds on, 1 second off, and a five field IMRT plan with 0.5 seconds on, 2.5 seconds off, had >90% passing rate. Conclusion: TrueBeam demonstrates excellent beam stability with minimal beam latencies under external device-based gated operations. Dosimetric measurements show minimal variation in beam energy, flatness, and plan delivery. Authors are employees of Varian Medical Systems, Inc.

  13. Feasibility of energy harvesting techniques for wearable medical devices.

    Science.gov (United States)

    Voss, Thaddaeus J; Subbian, Vignesh; Beyette, Fred R

    2014-01-01

    Wearable devices are arguably one of the most rapidly growing technologies in the computing and health care industry. These systems provide improved means of monitoring health status of humans in real-time. In order to cope with continuous sensing and transmission of biological and health status data, it is desirable to move towards energy autonomous systems that can charge batteries using passive, ambient energy. This not only ensures uninterrupted data capturing, but could also eliminate the need to frequently remove, replace, and recharge batteries. To this end, energy harvesting is a promising area that can lead to extremely power-efficient portable medical devices. This paper presents an experimental prototype to study the feasibility of harvesting two energy sources, solar and thermoelectric energy, in the context of wearable devices. Preliminary results show that such devices can be powered by transducing ambient energy that constantly surrounds us.

  14. Determination of the dose equivalents due to neutrons produced during therapeutic irradiations with a Varian CLINAC 2500; Determinacion de la dosis equivalente debida a neutrones producidos durante irradiaciones terapeuticas con un Varian CLINAC 2500

    Energy Technology Data Exchange (ETDEWEB)

    Carrillo, Ricardo E [Centro de Investigacion y de Estudios Avanzados del IPN, Unidad Merida, Yucatan (Mexico)

    1991-07-01

    This experiment it was designed to quantify that so important it is the dose equivalent deposited by the neutron flow that is generated by photonuclear reactions during therapeutic irradiations with X rays of produced high-energy for an accelerator Varian CLINAC 2500. This accelerator type is routinely used in the Department of Radiotherapy of the Hospital of the University of Wisconsin, E.U. The equivalent dose was measured in diverse towns of the room of irradiations using the activation of thin sheets of gold put in the center of plastic recipients full with water. In general, the recipients were 1 m or more than the floor and at distances still bigger than the walls. The irradiations were made using photons with the highest energy that you can select with this team - 24 MeV. The due equivalent dose to neutrons taken place here by the energy photons used they were measured and reported. (author)

  15. Monte Carlo simulation of the Varian Clinac 600C accelerator using dynamic wedges

    International Nuclear Information System (INIS)

    Moreno, S.; Chaves, A.; Lopes, M.C.; Peralta, L.; Universidade de Lisboa

    2004-01-01

    The advent of linear accelerators (linac) with computer-controlled dynamic collimation systems and functional and anatomical imaging techniques allowed a more exact delimitation and localisation of the target volume. These advanced treatment techniques inevitably increase the complexity level of dose calculation because of the introduction of the temporal variable. On account of this, it is mandatory the usage of more accurate modelling techniques of the collimator components, as it is the case of Monte Carlo (MC) simulation, which has created an enormous interest in research and clinical practice. Because the patients bodies are not homogenous nor are their body surfaces plane and regular, the dose distribution may differ significantly from the standard distribution from the linac calibration. It is in the treatment planning systems, which include algorithms that are usually measured in homogeneous water phantoms specific for each correction that the dose distributions from each case are obtained. In a real treatment, exception made to superficial lesions, two or more radiation fields are used in order to obtain the recommended dose distributions. The simplest arrangement is made from two parallel and opposed fields that originate a homogeneous dose distribution in almost all the irradiated volume. The available resources are, for example, different types of energies and of radiation, the application of bolus, the protection of healthy structures, the usage of wedged filters and the application of dynamic wedges. A virtual or dynamic wedge, modelled through the movement of one of the jaws, when compared with a set of physical wedges offers an alternative calculation method of an arbitrary number of wedged fields, instead of the four traditional fields of 15 deg, 30 deg, 45 deg and 60 deg angle and obtained with physical wedges. The goal of this work consists in the study of the application of dynamic wedges in tailoring the radiation field by the Varian Clinac 600

  16. Wireless energy transfer platform for medical sensors and implantable devices.

    Science.gov (United States)

    Zhang, Fei; Hackworth, Steven A; Liu, Xiaoyu; Chen, Haiyan; Sclabassi, Robert J; Sun, Mingui

    2009-01-01

    Witricity is a newly developed technique for wireless energy transfer. This paper presents a frequency adjustable witricity system to power medical sensors and implantable devices. New witricity resonators are designed for both energy transmission and reception. A prototype platform is described, including an RF power source, two resonators with new structures, and inductively coupled input and output stages. In vitro experiments, both in open air and using a human head phantom consisting of simulated tissues, are employed to verify the feasibility of this platform. An animal model is utilized to evaluate in vivo energy transfer within the body of a laboratory pig. Our experiments indicate that witricity is an effective new tool for providing a variety of medical sensors and devices with power.

  17. Determination of the dose equivalents due to neutrons produced during therapeutic irradiations with a Varian CLINAC 2500

    International Nuclear Information System (INIS)

    Carrillo, Ricardo E.

    1991-01-01

    This experiment it was designed to quantify that so important it is the dose equivalent deposited by the neutron flow that is generated by photonuclear reactions during therapeutic irradiations with X rays of produced high-energy for an accelerator Varian CLINAC 2500. This accelerator type is routinely used in the Department of Radiotherapy of the Hospital of the University of Wisconsin, E.U. The equivalent dose was measured in diverse towns of the room of irradiations using the activation of thin sheets of gold put in the center of plastic recipients full with water. In general, the recipients were 1 m or more than the floor and at distances still bigger than the walls. The irradiations were made using photons with the highest energy that you can select with this team - 24 MeV. The due equivalent dose to neutrons taken place here by the energy photons used they were measured and reported. (author)

  18. Monte Carlo simulation of Varian Linac for 6 MV photon beam with BEAMnrc code

    Science.gov (United States)

    Mohammed, Maged; El Bardouni, T.; Chakir, E.; Boukhal, H.; Saeed, M.; Ahmed, Abdul-Aziz

    2018-03-01

    The purpose of this study is to investigate the effects of the initial electron beam parameters on the absorbed dose distribution calculated with EGSnrc Monte Carlo code, for 6 MV photon beam. A proposed methodology for benchmarking the BEAMnrc model of Varian Linac has been used. Also, a new photon cross section data based on ENDF/B-VII release 8 evaluation has been employed. The parameters tested include mean energy, radial intensity distribution and angular spread of the initial electron beam. Mean energy and angular spread were tested for a square irradiation field 10 × 10 cm2, whereas beam width of the electron beam was studied for 10 × 10 cm2 at different depths and 30 × 30 cm2 at depth of 10 cm. The results obtained are compared with measurement data to select the optimal electron beam parameters. The differences between MC calculation and measurements data are analyzed using gamma index criteria which fixed within 1% -1 mm accuracy. The obtained results indicated that the depth-dose and dose-profile curves were considerably influenced by the mean energy of the electron beam. The depth-dose curves were unaffected by the beam width of the electron beam, for both irradiation fields. On the contrary, lateral dose-profile curves were affected by the beam width of initial electron beam. Both dose-profile and depth-dose curves were unaffected to the angular spread of the electron beam. A deep depth of 10 × 10 cm2 is very accurate to tune the beam width. Mean energy and beam width must be tuned precisely, to get the MC does distribution with acceptable accuracy.

  19. Monte Carlo simulation of the Varian Clinac 600C accelerator dynamic and physical wedges

    Energy Technology Data Exchange (ETDEWEB)

    Soares, S [Universidade da Beira Interior, Av. Marques d' Avila e Bolama, Covilha 6201-001 (Portugal); Chaves, A [Instituto Portugues de Oncologia Doutor Francisco Gentil (IPO), Av. Bissaya Barreto, Coimbra 3000-075 (Portugal); Peralta, L [Laboratorio de Instrumentacao e Fisica Experimental de PartIculas (LIP), Av. Elias Garcia no14 1o, Lisbon 1000-149 (Portugal); Lopes, Mc [Faculdade de Ciencias da Universidade de Lisboa, Campo Grande EdifIcio C5, Lisbon 1149-016 (Portugal)

    2007-06-15

    The present paper describes the study done on the dosimetric characteristics of the Varian Clinac 600C dynamic wedges (DW) and their comparison with the physical wedges (PW) in terms of the differences affecting the dose distributions, beam spectra, energy fluence and angular distributions. The geometry of the 4 MV photon beam and the dose distributions in a water phantom were simulated with GEANT3 and DPM Monte Carlo code systems. The DW was modelled through the constant movement of the upper jaws. The depth dose distributions and lateral profiles for the DW, PW and open fields were measured and compared with the Monte Carlo simulations and the global agreement was found to be within 3%. It was also found that the effects of a DW on beam spectral and angular distributions are much less significant than those produced by a PW. For example, in our study we found out that the 45{sup 0}PW, when compared with the corresponding open field, can introduce a 30% increase in the mean photon energy due to the beam hardening effect and that it can also introduce a 4.5% dose reduction in the build-up region because of the reduction of the contaminated electrons by the PW. For the DW neither this mean-energy increase nor such dose reduction was found. The PW, when compared to the DW, significantly alters the photon-beam spectrum and these dosimetric differences are significant and further investigation must be performed to quantify the impact in clinical use of these beams.

  20. On variation in Schloenbachia varians (J. Sowerby, 1817) from the Lower Cenomanian of western Kazakhstan

    Science.gov (United States)

    Kennedy, William James

    2013-12-01

    Kennedy, W.J. 2013. On variation in Schloenbachia varians (J. Sowerby, 1817) from the Lower Cenomanian of western Kazakhstan Acta Geologica Polonica, 63(4), 443-468. Warszawa. An assemblage of 94 specimens of Schloenbachia varians (J. Sowerby, 1817) from the Lower Cenomanian Sharpeiceras schlueteri Subzone of the Mantelliceras mantelli Zone of the Besakty section in the Mangyshlak Mountains of western Kazakhstan includes 26 complete adults that range from to 59-174 mm in diameter. No size-related dimorphism was detected in the assemblage, which shows wide, continuous intraspecific variation. This is described in terms of five formae; from robust to gracile these are: ventriosa, varians sensu stricto, subtuberculata , intermedia, and subplana. The ratio of robust (ventriosa + varians sensu stricto) to gracile (subtuberculata + intermedia + subplana) individuals is 34% to 66%. The reference specimens of the formae and their synonyms are described and illustrated, and related to the Besakty material. The modification of adult body chamber ornament of all formae is documented, and Jakeiceras Cooper and Owen, 2011 is shown to be based on an adult of a passage form between forma subtuberculata and forma intermedia. The differences between Lower Cenomanian S. varians, lower Middle Cenomanian S. coupei (Brongniart, 1822), and upper Middle and lower Upper Cenomanian S. lymensis Spath, 1926b are described and illustrated.

  1. Energy, emissions and emergency medical services: Policy matters

    International Nuclear Information System (INIS)

    Brown, Lawrence H.; Blanchard, Ian E.

    2012-01-01

    Understanding the energy consumption and emissions associated with health services is important for minimizing their environmental impact and guiding their adaptation to a low-carbon economy. In this post-hoc analysis, we characterize the energy burden of North American emergency medical services (EMS) agencies and estimate the potential marginal damage costs arising from their emissions as an example of how and why health services matter in environmental and energy policy, and how and why environmental and energy policy matter to health services. We demonstrate EMS systems are energy intensive, and that vehicle fuels represent 80% of their energy burden while electricity and natural gas represent 20%. We also demonstrate that emissions from EMS operations represent only a small fraction of estimated health sector emissions, but for EMS systems in the United States the associated marginal damage costs are likely between $2.7 million and $9.7 million annually. Significant changes in the supply or price of energy, including changes that arise from environmental and energy policy initiatives designed to constrain fossil fuel consumption, could potentially affect EMS agencies and other health services. We encourage cross disciplinary research to proactively facilitate the health system's adaptation to a low-carbon economy. - Highlights: ► Estimated EMS-related emissions less than 1% of health sector emissions. ► Damage costs of U.S. EMS-related emissions estimated at $2.7 to $9.7 million. ► EMS energy burden is approximately 442 MJ per ambulance response. ► Approximately 80% of EMS energy burden is vehicle fuels. ► Energy supply, price and policy could impact EMS (and other health) services. ► Research needed to facilitate health services’ adaptation to a low carbon economy.

  2. SU-E-T-405: Evaluation of the Raystation Electron Monte Carlo Algorithm for Varian Linear Accelerators

    Energy Technology Data Exchange (ETDEWEB)

    Sansourekidou, P; Allen, C [Health Quest, Poughkeepsie, NY (United States)

    2015-06-15

    Purpose: To evaluate the Raystation v4.51 Electron Monte Carlo algorithm for Varian Trilogy, IX and 2100 series linear accelerators and commission for clinical use. Methods: Seventy two water and forty air scans were acquired with a water tank in the form of profiles and depth doses, as requested by vendor. Data was imported into Rayphysics beam modeling module. Energy spectrum was modeled using seven parameters. Contamination photons were modeled using five parameters. Source phase space was modeled using six parameters. Calculations were performed in clinical version 4.51 and percent depth dose curves and profiles were extracted to be compared to water tank measurements. Sensitivity tests were performed for all parameters. Grid size and particle histories were evaluated per energy for statistical uncertainty performance. Results: Model accuracy for air profiles is poor in the shoulder and penumbra region. However, model accuracy for water scans is acceptable. All energies and cones are within 2%/2mm for 90% of the points evaluated. Source phase space parameters have a cumulative effect. To achieve distributions with satisfactory smoothness level a 0.1cm grid and 3,000,000 particle histories were used for commissioning calculations. Calculation time was approximately 3 hours per energy. Conclusion: Raystation electron Monte Carlo is acceptable for clinical use for the Varian accelerators listed. Results are inferior to Elekta Electron Monte Carlo modeling. Known issues were reported to Raysearch and will be resolved in upcoming releases. Auto-modeling is limited to open cone depth dose curves and needs expansion.

  3. Clinical application of image-guided radiotherapy, IGRT (on the Varian OBI platform)

    International Nuclear Information System (INIS)

    Sorcini, B.; Tilikidis, A.

    2006-01-01

    Image-guided radiation therapy (IGRT) can be used to measure and correct positional errors for target and critical structures immediately prior to or during treatment delivery. Some of the most recent available methods applied for target localization are: trans-abdominal ultrasound, implanted markers with in room MV or kV X-rays, optical surface tracking systems, implantable electromagnetic markers, in room CT such as kVCT on rail, kilo-voltage or mega-voltage cone-beam CT (CBCT) and helical megavoltage CT. The verification of the accurate treatment position in conjunction with detailed anatomical information before every fraction can be essential for the outcome of the treatment. In this paper we present the on-board imager (OBI, Varian Medical Systems, Palo Alto, CA) that has been in routine clinical use at the Karolinska University Hospital since June 2004. The OBI has been used for on-line set-up correction of prostate patients using internal gold markers. Displacements of these markers can be monitored radiographically during the treatment course and the registered marker shifts act as a surrogate for prostate motion. For this purpose, on-board kV-kV seems to be an ideal system in terms of image quality. The CBCT function of OBI was installed in March 2005 at our department. It focuses on localizing tumors based on internal anatomy, not just on the conventional external marks or tattoos. The CBCT system provides the capacity for soft tissue imaging in the treatment position and real-time radiographic monitoring during treatment delivery. (authors)

  4. SU-E-T-370: Measurement of Conical Cone Output Factors for the Varian Edge Linear Accelerator

    International Nuclear Information System (INIS)

    Li, H; Kim, J; Gordon, J; Chetty, I; Wang, S; Zhong, H; Wen, N

    2014-01-01

    Purpose: To quantify the impact of detector type, SSD/depth, and intermediate reference on conical cone output factor (OF) measurements for the Varian Edge linac. Methods: OF's for 4, 5, 7.5, 10, 12.5, 15, and 17.5 mm diameter cones relative to 10cmx10cm field were measured for the 6X FFF and 10X FFF energies, with jaws set to 5cmx5cm. Measurements were performed with an Edge diode (0.8mmx0.8mmx0.03mm WxLxT), stereotatic diode SFD, photon diode, CC01 and pinpoint chambers (2mm diameter for both). 95cm SSD/5cm depth were used in a water tank. For the measurement with diodes, OF's were cross-referred to CC13 ion chamber measurements with 3cmx3cm field, as recommended, to help mitigate the energy variation in diode response with field size. Results were compared to the representative data from Varian measured with Edge detector. With SFD, OF's at 98.5cm SSD/1.5cm depth and 90cm SSD/10cm depth were also measured. Results: OF's measured with the Edge detector matched within 1.3% (max diff) with the representative data from Varian. For the SFD, OF's matched within 1.3% for the 4, 5 and 17.5 mm cones and within 3.7% for the other cones. OF's with photon diode were within 1.3% except for the 4 and 5 mm cones where they were 8.1% and 3.7%, respectively. OF's for the CC01 and pinpoint chamber deviated up to 36% and 44%, respectively for the 4 mm cone. OF's after intermediate reference with 3cmx3cm field changed by 3.7% for SFD, 0.8% for photon diode, and 0.6% for Edge detector. OF's at 98.5cm SSD/1.5cm depth were 10.8% higher than that at 95cm SSD/5cm depth, and OF's at 90cm SSD/1.5cm depth were 7.5% lower. Conclusion: OF's measured with the Edge detector appear to be reliable. CC01 and pinpoint chambers do not appear suitable for measuring the small cone OF's. SSD/depth affects OF measurements significantly

  5. Bluetooth low energy: wireless connectivity for medical monitoring.

    Science.gov (United States)

    Omre, Alf Helge

    2010-03-01

    Electronic wireless sensors could cut medical costs by enabling physicians to remotely monitor vital signs such as blood pressure, blood glucose, and blood oxygenation while patients remain at home. According to the IDC report "Worldwide Bluetooth Semiconductor 2008-2012 Forecast," published November 2008, a forthcoming radio frequency communication ("wireless connectivity") standard, Bluetooth low energy, will link wireless sensors via radio signals to the 70% of cell phones and computers likely to be fitted with the next generation of Bluetooth wireless technology, leveraging a ready-built infrastructure for data transmission. Analysis of trends indicated by this data can help physicians better manage diseases such as diabetes. The technology also addresses the concerns of cost, compatibility, and interoperability that have previously stalled widespread adoption of wireless technology in medical applications. (c) 2010 Diabetes Technology Society.

  6. Acute effects of energy drinks in medical students.

    Science.gov (United States)

    García, Andrés; Romero, César; Arroyave, Cristhian; Giraldo, Fabián; Sánchez, Leidy; Sánchez, Julio

    2017-09-01

    To determine the acute effects of a variety of recognized energy drinks on medical students, based on the hypothesis that these beverages may affect negatively cardiovascular parameters, stress levels and working memory. Eighty young healthy medical students were included in the study. 62.5 % of the participants were male, and the age mean was 21.45 years. Each person was evaluated via measurement of systolic and diastolic blood pressure, electrocardiogram (ECG), heart rate, oxygen saturation, breath rate, temperature, STAI score (to assess anxiety state), salivary cortisol and N-back task score (to determine cognitive enhancement). These evaluations were performed before and following the intake of either carbonated water or one of three energy drinks containing caffeine in similar concentrations and an undetermined energy blend; A contained less sugar and no taurine. Thirty-minute SBP increased significantly in the A and C groups. The B group exhibited a diminution of the percentage of the 1-h SBP increase, an increase of 1-h DBP and QTc shortening. HR showed an increase in the percent change in the A and C groups. Cortisol salivary levels increased in the B group. The STAI test score decreased in the C group. The percent change in N-back scores increased in the A group. The data reinforce the need for further research on the acute and chronic effects of energy drinks to determine the actual risks and benefits. Consumers need to be more informed about the safety of these energy drinks, especially the young student population.

  7. Some advances in medical applications of low energy accelerators

    Science.gov (United States)

    Valković, V.; Moschini, G.

    1991-05-01

    Medical applications of low energy accelerators include: the use of nuclear analytical methods and procedures for laboratory studies and routine measurements; material productions and modifications to meet special requirements; radioisotope productions and their applications in radiopharmaceuticals as well as in positron emission tomography; and radiotherapy with ions, based on improved understanding of the interaction of charged particles with living tissue. Some of the recent advances in these fields are critically summarized. The plan for an improved charged particle facility in a hospital environment dedicated to applications in biology and medicine is presented.

  8. Medical radiation dosimetry theory of charged particle collision energy loss

    CERN Document Server

    McParland, Brian J

    2014-01-01

    Accurate radiation dosimetry is a requirement of radiation oncology, diagnostic radiology and nuclear medicine. It is necessary so as to satisfy the needs of patient safety, therapeutic and diagnostic optimisation, and retrospective epidemiological studies of the biological effects resulting from low absorbed doses of ionising radiation. The radiation absorbed dose received by the patient is the ultimate consequence of the transfer of kinetic energy through collisions between energetic charged particles and atoms of the tissue being traversed. Thus, the ability of the medical physicist to both measure and calculate accurately patient dosimetry demands a deep understanding of the physics of charged particle interactions with matter. Interestingly, the physics of charged particle energy loss has an almost exclusively theoretical basis, thus necessitating an advanced theoretical understanding of the subject in order to apply it appropriately to the clinical regime. ​ Each year, about one-third of the worl...

  9. Analysis of daily quality assurance tests for tomotherapy and two Varian linear accelerators - three months review

    International Nuclear Information System (INIS)

    Kushwaha, Pratishtha; Jaiswal, Deeksha; Dheera, A.; Upreti, Udita; Chaudhari, Suresh; Kinhikar, Rajesh; Deshpande, Deepak; Shrivastava, Shyam

    2016-01-01

    Daily quality assurance (QA) for high precision radiotherapy equipments is very important to maintain the mechanical and dosimetric accuracy for patient treatments. Gross deviations in these parameters may have an adverse impact on the delivery of the treatments to patients. We report the results of daily QA tests performed over a period of three months for two Varian linear accelerators and a Tomotherapy machine

  10. Active heater control and regulation for the Varian VGT-8011 gyrotron

    International Nuclear Information System (INIS)

    Harris, T.E.

    1991-10-01

    The Varian VGT-8011 gyrotron is currently being used in the new 110 GHz 2 MW ECH system installed on D3-D. This new ECH system augments the 60 GHz system which uses Varian VA-8060 gyrotrons. The new 110 GHz system will be used for ECH experiments on D3-D with a pulse width capability of 10 sec. In order to maintain a constant RF outpower level during long pulse operation, active filament-heater control and regulation is required to maintain a constant cathode current. On past D3-D experiments involving the use of Varian VA-8060 gyrotrons for ECH power, significant gyrotron heater-emission depletion was experienced for pulse widths > 300 msec. This decline in heater-emission directly results in gyrotron-cathode current droop. Since RF power from gyrotrons decreases as cathode current decreases, it is necessary to maintain a constant cathode current level during gyrotron pulses for efficient gyrotron operation. Therefore, it was determined that a filament-heater control system should be developed for the Varian VGT-8011 gyrotron which will include cathode-current feed-back. This paper discusses the mechanisms used to regulate gyrotron filament-heater voltage by using cathode-current feed-back. 1 fig

  11. SU-E-T-781: Using An Electronic Portal Imaging Device (EPID) for Correlating Linac Photon Beam Energies

    Energy Technology Data Exchange (ETDEWEB)

    Yaddanapudi, S; Cai, B; Sun, B; Noel, C; Goddu, S; Mutic, S [Washington University School of Medicine, Saint Louis, MO (United States)

    2015-06-15

    Purpose: Electronic portal imaging devices (EPIDs) have proven to be useful for measuring several parameters of interest in linear accelerator (linac) quality assurance (QA). The purpose of this project was to evaluate the feasibility of using EPIDs for determining linac photon beam energies. Methods: Two non-clinical Varian TrueBeam linacs (Varian Medical Systems, Palo Alto, CA) with 6MV and 10MV photon beams were used to perform the measurements. The linacs were equipped with an amorphous silicon based EPIDs (aSi1000) that were used for the measurements. We compared the use of flatness versus percent depth dose (PDD) for predicting changes in linac photon beam energy. PDD was measured in 1D water tank (Sun Nuclear Corporation, Melbourne FL) and the profiles were measured using 2D ion-chamber array (IC-Profiler, Sun Nuclear) and the EPID. Energy changes were accomplished by varying the bending magnet current (BMC). The evaluated energies conformed with the AAPM TG142 tolerance of ±1% change in PDD. Results: BMC changes correlating with a ±1% change in PDD corresponded with a change in flatness of ∼1% to 2% from baseline values on the EPID. IC Profiler flatness values had the same correlation. We observed a similar trend for the 10MV beam energy changes. Our measurements indicated a strong correlation between changes in linac photon beam energy and changes in flatness. For all machines and energies, beam energy changes produced change in the uniformity (AAPM TG-142), varying from ∼1% to 2.5%. Conclusions: EPID image analysis of beam profiles can be used to determine linac photon beam energy changes. Flatness-based metrics or uniformity as defined by AAPM TG-142 were found to be more sensitive to linac photon beam energy changes than PDD. Research funding provided by Varian Medical Systems. Dr. Sasa Mutic receives compensation for providing patient safety training services from Varian Medical Systems, the sponsor of this study.

  12. Energy efficiency improvement of medical electric tools and devices

    Directory of Open Access Journals (Sweden)

    Meshkov Aleksandr S.

    2014-01-01

    Full Text Available With the ever-increasing volume of applications of various kinds of electric drives in all spheres of human activity, the issues in improving the efficiency of the electromechanical converters of electric energy, one of the most important components of the electric drive (ED, are becoming increasingly important. Such issues include reducing their weight and size, improving the functional characteristics of these devices to increase their operational life and reducing the cost of manufacture. Taking full advantage of these opportunities relates to the AC and DC single-phase commutator motor (SCM, which is widely used in regulated and high-speed motor drives in medical electric hand tools. The SCM is used in machinery where the load torque has a hyperbolic dependence on the rotational speed and the need to work with a large motor overload due to the “soft” mechanical characteristics of such motors.

  13. Energy minimization in medical image analysis: Methodologies and applications.

    Science.gov (United States)

    Zhao, Feng; Xie, Xianghua

    2016-02-01

    Energy minimization is of particular interest in medical image analysis. In the past two decades, a variety of optimization schemes have been developed. In this paper, we present a comprehensive survey of the state-of-the-art optimization approaches. These algorithms are mainly classified into two categories: continuous method and discrete method. The former includes Newton-Raphson method, gradient descent method, conjugate gradient method, proximal gradient method, coordinate descent method, and genetic algorithm-based method, while the latter covers graph cuts method, belief propagation method, tree-reweighted message passing method, linear programming method, maximum margin learning method, simulated annealing method, and iterated conditional modes method. We also discuss the minimal surface method, primal-dual method, and the multi-objective optimization method. In addition, we review several comparative studies that evaluate the performance of different minimization techniques in terms of accuracy, efficiency, or complexity. These optimization techniques are widely used in many medical applications, for example, image segmentation, registration, reconstruction, motion tracking, and compressed sensing. We thus give an overview on those applications as well. Copyright © 2015 John Wiley & Sons, Ltd.

  14. PERBEDAAN MUSIM TANAM TERHADAP PERFORMA BUDIDAYA EMPAT VARIAN RUMPUT LAUT EUCHEUMATOIDS DI TELUK GERUPUK, NUSA TENGGARA BARAT

    Directory of Open Access Journals (Sweden)

    Erlania Erlania

    2014-08-01

    Full Text Available Musim tanam rumput laut di perairan Teluk Gerupuk dikelompokkan menjadi musim produktif dan non-produktif. Penelitian ini bertujuan untuk menganalisis perbedaan performa budidaya dari empat varian rumput laut: Kappaphycus alvarezii varian Tambalang dan Maumere, Eucheuma denticulatum, dan K. striatum yang dibudidayakan di perairan Teluk Gerupuk dengan metode long line pada musim tanam yang berbeda. Pengamatan terhadap parameter performa budidaya meliputi laju pertumbuhan harian, pertambahan biomassa, dan produksi rumput laut, yang dilakukan setiap 15 hari sekali selama masa budidaya yaitu 45 hari per siklus. Pengamatan dilakukan selama tiga siklus tanam dari bulan Juli-Desember. Analisis ragam (ANOVA dengan rancangan acak lengkap faktorial dan uji lanjut Tukey Test dilakukan untuk mengetahui pengaruh perbedaan varian rumput laut dan periode musim tanam terhadap parameter yang diamati. Hasil penelitian menunjukkan bahwa musim tanam (produktif dan non-produktif merupakan salah satu aspek penting yang berpengaruh nyata terhadap performa budidaya rumput laut (P<0,05. Dari keempat varian yang dibudidayakan, E. denticulatum merupakan varian yang memiliki performa terbaik yang berbeda nyata dengan ketiga varian lainnya (P<0,05, baik pada musim produktif maupun musim non-produktif. Pemilihan varian rumput laut yang tepat dengan tingkat pertumbuhan dan daya adaptasi yang lebih baik terhadap perbedaan kondisi lingkungan merupakan salah satu kunci keberhasilan dan keberlanjutan budidaya rumput laut.

  15. TU-F-CAMPUS-T-04: An Evaluation of Out-Of-Field Doses for Electron Beams From Modern Varian and Elekta Linear Accelerators

    Energy Technology Data Exchange (ETDEWEB)

    Cardenas, C; Nitsch, P; Kudchadker, R; Howell, R; Kry, S [UT MD Anderson Cancer Center, Houston, TX (United States)

    2015-06-15

    Purpose: Accurately determining out-of-field doses when using electron beam radiotherapy is of importance when treating pregnant patients or patients with implanted electronic devices. Scattered doses outside of the applicator field in electron beams have not been broadly investigated, especially since manufacturers have taken different approaches in applicator designs. Methods: In this study, doses outside of the applicator field were measured for electron beams produced by a 10×10 applicator on two Varian 21iXs operating at 6, 9, 12, 16, and 20 MeV, a Varian TrueBeam operating at 6, 9, 12, 16, and 20 MeV, and an Elekta Versa HD operating at 6, 9, 12 and 15 MeV. Peripheral dose profiles and percent depth doses were measured in a Wellhofer water phantom at 100 cm SSD with a Farmer ion chamber. Doses were compared to peripheral photon doses from AAPM’s Task Group #36 report. Results: Doses were highest for the highest electron energies. Doses typically decreased with increasing distance from the field edge but showed substantial increases over some distance ranges. Substantial dose differences were observed between different accelerators; the Elekta accelerator had much higher doses than any Varian unit examined. Surprisingly, doses were often similar to, and could be much higher than, doses from photon therapy. Doses decreased sharply with depth before becoming nearly constant; the dose was found to decrease to a depth of approximately E(MeV)/4 in cm. Conclusion: The results of this study indicate that proper shielding may be very important when utilizing electron beams, particularly on a Versa HD, while treating pregnant patients or those with implanted electronic devices. Applying a water equivalent bolus of Emax(MeV)/4 thickness (cm) on the patient would reduce fetal dose drastically for all clinical energies and is a practical solution to manage the potentially high peripheral doses seen from modern electron beams. Funding from NIH Grant number: #CA180803.

  16. SU-F-T-262: Commissioning Varian Portal Dosimetry for EPID-Based Patient Specific QA in a Non-Aria Environment

    Energy Technology Data Exchange (ETDEWEB)

    Schmidt, M; Knutson, N [Rhode Island Hospital, Providence RI (United States); University of Rhode Island, Kingston, RI (United States); University of Massachusetts Lowell, Lowell, MA (United States); Herrington, J [University of Rhode Island, Kingston, RI (United States); Price, M [Rhode Island Hospital, Providence RI (United States); University of Rhode Island, Kingston, RI (United States); Alpert Medical School of Brown University, Providence, RI (United States)

    2016-06-15

    Purpose: Development of an in-house program facilitates a workflow that allows Electronic Portal Imaging Device (EPID) patient specific quality assurance (QA) measurements to be acquired and analyzed in the Portal Dosimetry Application (Varian Medical Systems, Palo Alto, CA) using a non-Aria Record and Verify (R&V) system (MOSAIQ, Elekta, Crawley, UK) to deliver beams in standard clinical treatment mode. Methods: Initial calibration of an in-house software tool includes characterization of EPID dosimetry parameters by importing DICOM images of varying delivered MUs to determine linear mapping factors in order to convert image pixel values to Varian-defined Calibrated Units (CU). Using this information, the Portal Dose Image Prediction (PDIP) algorithm was commissioned by converting images of various field sizes to output factors using the Eclipse Scripting Application Programming Interface (ESAPI) and converting a delivered configuration fluence to absolute dose units. To verify the algorithm configuration, an integrated image was acquired, exported directly from the R&V client, automatically converted to a compatible, calibrated dosimetric image, and compared to a PDIP calculated image using Varian’s Portal Dosimetry Application. Results: For two C-Series and one TrueBeam Varian linear accelerators, gamma comparisons (global 3% / 3mm) of PDIP algorithm predicted dosimetric images and images converted via the inhouse system demonstrated agreement for ≥99% of all pixels, exceeding vendor-recommended commissioning guidelines. Conclusion: Combinations of a programmatic image conversion tool and ESAPI allow for an efficient and accurate method of patient IMRT QA incorporating a 3rd party R&V system.

  17. A Monte Carlo simulation framework for electron beam dose calculations using Varian phase space files for TrueBeam Linacs.

    Science.gov (United States)

    Rodrigues, Anna; Sawkey, Daren; Yin, Fang-Fang; Wu, Qiuwen

    2015-05-01

    To develop a framework for accurate electron Monte Carlo dose calculation. In this study, comprehensive validations of vendor provided electron beam phase space files for Varian TrueBeam Linacs against measurement data are presented. In this framework, the Monte Carlo generated phase space files were provided by the vendor and used as input to the downstream plan-specific simulations including jaws, electron applicators, and water phantom computed in the EGSnrc environment. The phase space files were generated based on open field commissioning data. A subset of electron energies of 6, 9, 12, 16, and 20 MeV and open and collimated field sizes 3 × 3, 4 × 4, 5 × 5, 6 × 6, 10 × 10, 15 × 15, 20 × 20, and 25 × 25 cm(2) were evaluated. Measurements acquired with a CC13 cylindrical ionization chamber and electron diode detector and simulations from this framework were compared for a water phantom geometry. The evaluation metrics include percent depth dose, orthogonal and diagonal profiles at depths R100, R50, Rp, and Rp+ for standard and extended source-to-surface distances (SSD), as well as cone and cut-out output factors. Agreement for the percent depth dose and orthogonal profiles between measurement and Monte Carlo was generally within 2% or 1 mm. The largest discrepancies were observed within depths of 5 mm from phantom surface. Differences in field size, penumbra, and flatness for the orthogonal profiles at depths R100, R50, and Rp were within 1 mm, 1 mm, and 2%, respectively. Orthogonal profiles at SSDs of 100 and 120 cm showed the same level of agreement. Cone and cut-out output factors agreed well with maximum differences within 2.5% for 6 MeV and 1% for all other energies. Cone output factors at extended SSDs of 105, 110, 115, and 120 cm exhibited similar levels of agreement. We have presented a Monte Carlo simulation framework for electron beam dose calculations for Varian TrueBeam Linacs. Electron beam energies of 6 to 20 MeV for open and collimated

  18. Technical Report: Reference photon dosimetry data for Varian accelerators based on IROC-Houston site visit data

    Energy Technology Data Exchange (ETDEWEB)

    Kerns, James R.; Followill, David S.; Kry, Stephen F., E-mail: sfkry@mdanderson.org [Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, Texas 77030 (United States); Imaging and Radiation Oncology Core-Houston, The University of Texas MD Anderson Cancer Center, Houston, Texas 77030 (United States); Graduate School of Biomedical Sciences, The University of Texas Health Science Center-Houston, Houston, Texas 77030 (United States); Lowenstein, Jessica; Molineu, Andrea; Alvarez, Paola; Taylor, Paige A. [Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, Texas 77030 (United States); Imaging and Radiation Oncology Core-Houston, The University of Texas MD Anderson Cancer Center, Houston, Texas 77030 (United States); Stingo, Francesco C. [Department of Biostatistics, The University of Texas MD Anderson Cancer Center, Houston, Texas 77030 (United States)

    2016-05-15

    Purpose: Accurate data regarding linear accelerator (Linac) radiation characteristics are important for treatment planning system modeling as well as regular quality assurance of the machine. The Imaging and Radiation Oncology Core-Houston (IROC-H) has measured the dosimetric characteristics of numerous machines through their on-site dosimetry review protocols. Photon data are presented and can be used as a secondary check of acquired values, as a means to verify commissioning a new machine, or in preparation for an IROC-H site visit. Methods: Photon data from IROC-H on-site reviews from 2000 to 2014 were compiled and analyzed. Specifically, data from approximately 500 Varian machines were analyzed. Each dataset consisted of point measurements of several dosimetric parameters at various locations in a water phantom to assess the percentage depth dose, jaw output factors, multileaf collimator small field output factors, off-axis factors, and wedge factors. The data were analyzed by energy and parameter, with similarly performing machine models being assimilated into classes. Common statistical metrics are presented for each machine class. Measurement data were compared against other reference data where applicable. Results: Distributions of the parameter data were shown to be robust and derive from a student’s t distribution. Based on statistical and clinical criteria, all machine models were able to be classified into two or three classes for each energy, except for 6 MV for which there were eight classes. Quantitative analysis of the measurements for 6, 10, 15, and 18 MV photon beams is presented for each parameter; supplementary material has also been made available which contains further statistical information. Conclusions: IROC-H has collected numerous data on Varian Linacs and the results of photon measurements from the past 15 years are presented. The data can be used as a comparison check of a physicist’s acquired values. Acquired values that are well

  19. Technical Report: Reference photon dosimetry data for Varian accelerators based on IROC-Houston site visit data

    International Nuclear Information System (INIS)

    Kerns, James R.; Followill, David S.; Kry, Stephen F.; Lowenstein, Jessica; Molineu, Andrea; Alvarez, Paola; Taylor, Paige A.; Stingo, Francesco C.

    2016-01-01

    Purpose: Accurate data regarding linear accelerator (Linac) radiation characteristics are important for treatment planning system modeling as well as regular quality assurance of the machine. The Imaging and Radiation Oncology Core-Houston (IROC-H) has measured the dosimetric characteristics of numerous machines through their on-site dosimetry review protocols. Photon data are presented and can be used as a secondary check of acquired values, as a means to verify commissioning a new machine, or in preparation for an IROC-H site visit. Methods: Photon data from IROC-H on-site reviews from 2000 to 2014 were compiled and analyzed. Specifically, data from approximately 500 Varian machines were analyzed. Each dataset consisted of point measurements of several dosimetric parameters at various locations in a water phantom to assess the percentage depth dose, jaw output factors, multileaf collimator small field output factors, off-axis factors, and wedge factors. The data were analyzed by energy and parameter, with similarly performing machine models being assimilated into classes. Common statistical metrics are presented for each machine class. Measurement data were compared against other reference data where applicable. Results: Distributions of the parameter data were shown to be robust and derive from a student’s t distribution. Based on statistical and clinical criteria, all machine models were able to be classified into two or three classes for each energy, except for 6 MV for which there were eight classes. Quantitative analysis of the measurements for 6, 10, 15, and 18 MV photon beams is presented for each parameter; supplementary material has also been made available which contains further statistical information. Conclusions: IROC-H has collected numerous data on Varian Linacs and the results of photon measurements from the past 15 years are presented. The data can be used as a comparison check of a physicist’s acquired values. Acquired values that are well

  20. Recent operating experience with Varian 70 GHz and 140 GHz gyrotrons

    International Nuclear Information System (INIS)

    Felch, K.; Bier, R.; Fox, L.; Huey, H.; Ives, L.; Jory, H.; Lopez, N.; Shively, J.; Spang, S.

    1985-01-01

    The design features and initial test results of Varian 70 GHz and 140 GHz CW gyrotrons are presented. The first experimental 140 GHz tube has achieved an output power of 102 kW at 24% efficiency under pulsed conditions in the desired TE 031 0 cavity mode. Further tests aimed at achieving the design goal of 100 kW CW are currently underway. The 70 GHz tube has achieved an output power of 200 kW under pulsed conditions and possesses a wide dynamic range for output power variations. 6 refs., 8 figs

  1. Studying the induced radioactivity of a varian clinac 2100C/D accelerator

    International Nuclear Information System (INIS)

    Lu Feng; Li Hailiang; Deng Daping; Shang Yunying; Jing Zhongjun

    2008-01-01

    Objective: To Study the influences of dose, time, distance and irradiation mode on induced radioactivity by measuring a Varian Clinac 2100C/D accelerator. Methods: The induced radioactivity was measured in different dose, time, distance and irradiation mode by using of 450P model dosemeter. The results was analysed. Results: The induced radioactivity is direct ratio with dose, inverse ratio with time and distance. In different irradiation mode, the induced radioactivity is different. Conclusion: The induced radioactivity level of accelerator is related with dose, time, distance and irradiation mode. (authors)

  2. Characterization of the radiation environment at the UNLV accelerator facility during operation of the Varian M6 linac

    International Nuclear Information System (INIS)

    Hodges, M.; Barzilov, A.; Chen, Y.; Lowe, D.

    2016-01-01

    The bremsstrahlung photon flux from the UNLV particle accelerator (Varian M6 model) was determined using MCNP5 code for 3 MeV and 6 MeV incident electrons. Human biological equivalent dose rates due to accelerator operation were evaluated using the photon flux with the flux-to-dose conversion factors. Dose rates were computed for the accelerator facility for M6 linac use under different operating conditions. The results showed that the use of collimators and linac internal shielding significantly reduced the dose rates throughout the facility. It was shown that the walls of the facility, in addition to the earthen berm enveloping the building, provide equivalent shielding to reduce dose rates outside to below the 2 mrem/h limit. - Highlights: • A 3/6 MeV electron accelerator equipped with a high energy x-ray target was studied. • Monte Carlo modeling of photon flux was carried out for three accelerator configurations. • Human biological equivalent doses were evaluated within the accelerator facility building.

  3. The growth of Micrococcus varians by utilizing sugar cane blackstrap molasses as substrate

    Directory of Open Access Journals (Sweden)

    Miranda Luís A. S.

    1999-01-01

    Full Text Available Comparative studies on the growth of Micrococcus varians were carried out in BHI culture medium (control as well as in a culture medium with 2% diluted sugar cane blackstrap molasses, enriched with 0.1% yeast extract. The experiment was conducted with three samples of the experimental and control media in a 5 liter fermentor with working volume of 3.5 liters, continuous agitation (150 rpm, 35 ± 0.1°C temperature, 0.7 L air. l-1 medium. min -1, initial pH 7.0 ± 0.2, 24 hour fermentation period, and approximate inoculum of 6.0 log10 CFU/ml. Samples were collected at 2-hour intervals. Micrococcus varians grew in the two culture media studied, which confirms the experimental medium viability for the growth of this species. The final average concentration of biomass was higher in the control medium than in the experimental medium: 0.99 g.l-1 and 0.78 g.l-1, respectively. The final number of viable cells at the end of fermentation was 20.65 log10 CFU/ml for the control medium (BHI, while in the experimental medium the number of viable cells was 19.43 log10 CFU/ml. The consumption of total sugars was higher for the biomass in the control medium (79.78%, while only 50.53% was consumed for the experimental medium.

  4. Uptake and depuration of PCB-153 in edible shrimp Palaemonetes varians and human health risk assessment.

    Science.gov (United States)

    Grilo, T F; Cardoso, P G; Pato, P; Duarte, A C; Pardal, M A

    2014-03-01

    A medium-term mesocosm exposure study was conducted to elucidate bioaccumulation and depuration of polychlorinated biphenyl congener 153 (PCB-153) in edible shrimp Palaemonetes varians. Over the 15-day exposure period, shrimp under different exposure concentrations exhibited a significant increase in PCB-153 concentration compared with control organisms. Distinct bioaccumulation patterns and uptake rates were observed depending on the exposure concentrations. For low PCB-153 exposure levels (0.25μgL(-1)), accumulation followed a saturation model, reaching an apparent steady state after fifteen days exposure. For intermediate (2.5μgL(-1)) and high PCB-153 levels (25μgL(-1)), accumulation was faster and linear. In addition, the bioaccumulation rate was not proportional to PCB-153 concentration, and the bioaccumulation was higher at intermediate exposure concentrations. Regarding the depuration phase, P. varians lost up to 30% of PCB-153 after 72h and levels continued slowly to decrease until the end of the 30-d experimental period. However, PCB-153 levels in shrimp did not reach background values, and those exposed to moderate and high PCB-153 concentrations presented contamination levels much higher than the regulatory limit for human food consumption (75ngg(-1) ww for Σ6 PCB). Copyright © 2013 Elsevier Inc. All rights reserved.

  5. Dual energy CT: New horizon in medical imaging

    Energy Technology Data Exchange (ETDEWEB)

    Goo, Hyun Woo [Dept. of Radiology and Research Institute of Radiology, Asan Medical Center, University of Ulsan College of Medicine, Seoul (Korea, Republic of); Goo, Jin Mo [Dept. of Radiology, Seoul National University College of Medicine, Seoul (Korea, Republic of)

    2017-08-01

    Dual-energy CT has remained underutilized over the past decade probably due to a cumbersome workflow issue and current technical limitations. Clinical radiologists should be made aware of the potential clinical benefits of dual-energy CT over single-energy CT. To accomplish this aim, the basic principle, current acquisition methods with advantages and disadvantages, and various material-specific imaging methods as clinical applications of dual-energy CT should be addressed in detail. Current dual-energy CT acquisition methods include dual tubes with or without beam filtration, rapid voltage switching, dual-layer detector, split filter technique, and sequential scanning. Dual-energy material-specific imaging methods include virtual monoenergetic or monochromatic imaging, effective atomic number map, virtual non-contrast or unenhanced imaging, virtual non-calcium imaging, iodine map, inhaled xenon map, uric acid imaging, automatic bone removal, and lung vessels analysis. In this review, we focus on dual-energy CT imaging including related issues of radiation exposure to patients, scanning and post-processing options, and potential clinical benefits mainly to improve the understanding of clinical radiologists and thus, expand the clinical use of dual-energy CT; in addition, we briefly describe the current technical limitations of dual-energy CT and the current developments of photon-counting detector.

  6. Dual-Energy CT: New Horizon in Medical Imaging.

    Science.gov (United States)

    Goo, Hyun Woo; Goo, Jin Mo

    2017-01-01

    Dual-energy CT has remained underutilized over the past decade probably due to a cumbersome workflow issue and current technical limitations. Clinical radiologists should be made aware of the potential clinical benefits of dual-energy CT over single-energy CT. To accomplish this aim, the basic principle, current acquisition methods with advantages and disadvantages, and various material-specific imaging methods as clinical applications of dual-energy CT should be addressed in detail. Current dual-energy CT acquisition methods include dual tubes with or without beam filtration, rapid voltage switching, dual-layer detector, split filter technique, and sequential scanning. Dual-energy material-specific imaging methods include virtual monoenergetic or monochromatic imaging, effective atomic number map, virtual non-contrast or unenhanced imaging, virtual non-calcium imaging, iodine map, inhaled xenon map, uric acid imaging, automatic bone removal, and lung vessels analysis. In this review, we focus on dual-energy CT imaging including related issues of radiation exposure to patients, scanning and post-processing options, and potential clinical benefits mainly to improve the understanding of clinical radiologists and thus, expand the clinical use of dual-energy CT; in addition, we briefly describe the current technical limitations of dual-energy CT and the current developments of photon-counting detector.

  7. Treatment-Planning Study of Prostate Cancer Intensity-Modulated Radiotherapy With a Varian Clinac Operated Without a Flattening Filter

    International Nuclear Information System (INIS)

    Vassiliev, Oleg N.; Kry, Stephen F.; Kuban, Deborah A.; Salehpour, Mohammad; Mohan, Radhe; Titt, Uwe

    2007-01-01

    Purpose: To assess the feasibility of intensity-modulated radiotherapy for prostate cancer using photon beams from an accelerator operated without a flattening filter; and to determine potential benefits and drawbacks of using unflattened beams for this type of treatment. Methods and Materials: Intensity-modulated radiotherapy plans were generated for 10 patients with early-stage prostate cancer. For each patient, four plans were generated: with and without the flattening filter, at 6 and 18 MV. The prescription dose was 75.6 Gy to 98% of the planning target volume. The number of beams, their orientations, and optimization constraints were the same for all plans. Plans were generated with Eclipse 8.0 (Varian Medical Systems). Results: All the plans developed with unflattened beams were clinically acceptable. In terms of patient dose distributions, plans with unflattened beams were similar to the corresponding plans with flattened beams. Plans with unflattened beams required fewer monitor units (MUs) per plan: on average, by a factor of 2.0 at 6 MV and 2.6 at 18 MV, assuming that removal of the flattening filter was not followed by recalibration of MUs. Conclusions: Clinically acceptable intensity-modulated radiotherapy plans for prostate cancer can be developed with unflattened beams at both 6 and 18 MV. Dosimetrically, flattened and unflattened beams generated similar treatment plans. The plans with unflattened beams required substantially fewer MUs. The reduction in the number of MUs indicates corresponding reduction in beam-on time and in the amount of radiation outside the target

  8. Energy Survey of Eisenhower Army Medical Center, Fort Gordon, Augusta, Georgia. Volume 2. Appendices

    National Research Council Canada - National Science Library

    1996-01-01

    ...) including low cost/no cost ECO's and perform complete evaluations of each. Energy equipment replacement projects already underway, approved, or planned by the Medical Center staff will be factored into the evaluations...

  9. Validation of FORTRAN emulators for the G2 varian control programs

    International Nuclear Information System (INIS)

    Delorme, G.

    1996-01-01

    The extensive use of the Gentilly full scope simulator for training and verification of plant procedures, forced the development of a reliable desktop simulator for software maintenance purposes. For that we needed emulators for the control programs which run on the DCC Varian computers in the full scope simulator. This paper presents the validation results for the Reactor Regulating System (RRS) program. This emulator was programmed in a modular fashion providing ease of maintenance and of transportation to another environment. The results obtained with specific tests or with integrated testing involving complex control rule interactions, compared favorably with the ones obtained using the actual plant control programs running on the full scope simulator, which constitutes an irrefutable validation procedure. This RRS package along with the other emulators being validated In this manner could be used in safety codes with confidence. (author)

  10. TU-FG-201-05: Varian MPC as a Statistical Process Control Tool

    International Nuclear Information System (INIS)

    Carver, A; Rowbottom, C

    2016-01-01

    Purpose: Quality assurance in radiotherapy requires the measurement of various machine parameters to ensure they remain within permitted values over time. In Truebeam release 2.0 the Machine Performance Check (MPC) was released allowing beam output and machine axis movements to be assessed in a single test. We aim to evaluate the Varian Machine Performance Check (MPC) as a tool for Statistical Process Control (SPC). Methods: Varian’s MPC tool was used on three Truebeam and one EDGE linac for a period of approximately one year. MPC was commissioned against independent systems. After this period the data were reviewed to determine whether or not the MPC was useful as a process control tool. Analyses on individual tests were analysed using Shewhart control plots, using Matlab for analysis. Principal component analysis was used to determine if a multivariate model was of any benefit in analysing the data. Results: Control charts were found to be useful to detect beam output changes, worn T-nuts and jaw calibration issues. Upper and lower control limits were defined at the 95% level. Multivariate SPC was performed using Principal Component Analysis. We found little evidence of clustering beyond that which might be naively expected such as beam uniformity and beam output. Whilst this makes multivariate analysis of little use it suggests that each test is giving independent information. Conclusion: The variety of independent parameters tested in MPC makes it a sensitive tool for routine machine QA. We have determined that using control charts in our QA programme would rapidly detect changes in machine performance. The use of control charts allows large quantities of tests to be performed on all linacs without visual inspection of all results. The use of control limits alerts users when data are inconsistent with previous measurements before they become out of specification. A. Carver has received a speaker’s honorarium from Varian

  11. Recent topical research on global, energy, health & medical, and tourism economics, and global software: An overview

    OpenAIRE

    Chang, Chia-Lin; McAleer, Michael

    2017-01-01

    textabstractThe paper presents an overview of recent topical research on global, energy, health & medical, and tourism economics, and global software. We have interpreted "global" in the title of the Journal of Reviews on Global Economics to cover contributions that have a global impact on economics, thereby making it "global economics". In this sense, the paper is concerned with papers on global, energy, health & medical, and tourism economics, as well as global software algorithms that have...

  12. Recent Topical Research on Global, Energy, Health & Medical, and Tourism Economics, and Global Software

    OpenAIRE

    Chang, Chia-Lin; McAleer, Michael

    2017-01-01

    textabstractThe paper presents an overview of recent topical research on global, energy, health & medical, and tourism economics, and global software. We have interpreted “global” in the title of the Journal of Reviews on Global Economics to cover contributions that have a global impact on economics, thereby making it “global economics”. In this sense, the paper is concerned with papers on global, energy, health & medical, and tourism economics, as well as global software algorithms that have...

  13. Implementation of the program of quality control of the system on-board imager of varian: initial assessment; Puesta en marcha del programa de control de calidad del sistema on-board imager de varian: evaluacion inicial

    Energy Technology Data Exchange (ETDEWEB)

    Ortega Martin, I.; Ruiz Morales, C.; Lopez Sanchez, F.; Tobarra Gonzalez, B. M.

    2013-07-01

    This work aims to present evidence that are part of our quality control system on-board Imager of Varian, elaborated from recommendations and national and international protocols, as well as a first assessment of the results obtained to date. (Author)

  14. Additive, control, energy, medical and other hot topics

    NARCIS (Netherlands)

    Brouwer, Dannis Michel

    2014-01-01

    The 14th International Conference of the European Society for Precision Engineering and Nanotechnology (euspen) was held in Dubrovnik, Croatia, on 2-6 June 2014. Among the hot topics discussed were additive manufacturing (AM), motion control in precision systems, renewable energy technologies, and

  15. Modelling of a linear accelerator VARIAN 600 C/D for dosimetric study using the Monte Carlo Method

    International Nuclear Information System (INIS)

    Cancino, Jorge Luis Batista

    2016-01-01

    Based on the high availability of low energy linear accelerators in Brazil and with the goal of developing a reliable tool for dose distribution calculations in radiotherapy; this research aims to validate a linear accelerator head model using MCNP Monte Carlo code. The Varian 600 C/D linear accelerator installed at the Hospital São João de is taken as reference. The main components of the linear accelerator head were simulated based on detailed information of the manufacturer. In order to calculate dose distribution, a water phantom with dimensions of 30 x 30 x 30 cm 3 was simulated and placed at 100 cm of source-surface distance. A monoenergetic electron beam of 6,3 MeV was considered as a source. The number of primary particles used in the simulation was 10 8 . A Phase-Space Surface was used to scoring the photon spectrum below the tungsten target. Others two were placed in the model in order to reduce computational time and improve statistical accuracy. In order to validate the developed model, the X-ray spectrum generated by Bremsstrahlung was calculated and analyzed. Furthermore, the results of percentage depth doses and beam profiles calculations were compared with available measurements. The MCNP calculations results were compared to measurement showing good agreement between them. The comparison between MCNP calculations and measurement of PDD showed reasonable coherence at build-up region. The results were in an acceptable interval of confidence at the flat region of beam profiles comparison for three different field sizes. In this work, we compared MCNP calculations to experimental data in order to validate the developed LINAC head model. The results showed a good agreement according to the recommended criteria. The developed model was validated as an accurate tool for LINAC quality control procedures. (author)

  16. Medical risks presented by different types of energy

    Energy Technology Data Exchange (ETDEWEB)

    1980-03-01

    This article reports on discussions held during the conference which took place in Paris from 24th to 28th January 1980 and covered the following topics:- The risk concept from the point of view of the epidemiologist and the engineer - perception of the risk. The gulf which exists between the objective risk and that perceived by the public. The need to realize this phenomenon. The particular problems of each type of energy: coal (industrial diseases) - oil - gas - nuclear power (irradiation). Long-term effects and problems: air pollution and effects on health, the growth effect on stocks of atmospheric carbon, water pollution. The methodology of comparative studies of the risks presented by different types of energy. (In French)

  17. Sustainable emergency medical service systems: how much energy do we need?

    Science.gov (United States)

    Brown, Lawrence H; Blanchard, Ian E

    2015-02-01

    Modern emergency medical service (EMS) systems are vulnerable to both rising energy prices and potential energy shortages. Ensuring the sustainability of EMS systems requires an empirical understanding of the total energy requirements of EMS operations. This study was undertaken to determine the life cycle energy requirements of US EMS systems. Input-output-based energy requirement multipliers for the US economy were applied to the annual budgets for a random sample of 19 metropolitan or county-wide EMS systems. Calculated per capita energy requirements of the EMS systems were used to estimate nationwide EMS energy requirements, and the leading energy sinks of the EMS supply chain were determined. Total US EMS-related energy requirements are estimated at 30 to 60 petajoules (10(15) J) annually. Direct ("scope 1") energy consumption, primarily in the form of vehicle fuels but also in the form of natural gas and heating oil, accounts for 49% of all EMS-related energy requirements. The energy supply chain-including system electricity consumption ("scope 2") as well as the upstream ("scope 3") energy required to generate and distribute liquid fuels and natural gas-accounts for 18% of EMS energy requirements. Scope 3 energy consumption in the materials supply chain accounts for 33% of EMS energy requirements. Vehicle purchases, leases, maintenance, and repair are the most energy-intense components of the non-energy EMS supply chain (23%), followed by medical supplies and equipment (21%). Although less energy intense than other aspects of the US healthcare system, ground EMS systems require substantial amounts of energy each year. Copyright © 2014 Elsevier Inc. All rights reserved.

  18. Application of halophilic nuclease H of Micrococcus varians subsp. halophilus to commercial production of flavoring agent 5'-GMP.

    Science.gov (United States)

    Kamekura, M; Hamakawa, T; Onishi, H

    1982-01-01

    RNA was degraded at 60 degrees C for 24 h by halophilic nuclease H in supernatants from broth cultures of Micrococcus varians subsp. halophilus containing 12% NaCl. Since contaminating 5'-nucleotidase exhibited almost no activity under these conditions, the 5'-GMP formed could be recovered from the reaction mixture, and the yield was 805 mg from 5 g of RNA. PMID:6184020

  19. Implementation of the program of quality control of the system on-board imager of varian: initial assessment

    International Nuclear Information System (INIS)

    Ortega Martin, I.; Ruiz Morales, C.; Lopez Sanchez, F.; Tobarra Gonzalez, B. M.

    2013-01-01

    This work aims to present evidence that are part of our quality control system on-board Imager of Varian, elaborated from recommendations and national and international protocols, as well as a first assessment of the results obtained to date. (Author)

  20. Intermittent energy restriction in type 2 diabetes: A short discussion of medication management.

    Science.gov (United States)

    Carter, Sharayah; Clifton, Peter M; Keogh, Jennifer B

    2016-12-15

    To discuss type 2 diabetes mellitus (T2DM) medication changes required during the popular 5:2 intermittent energy restriction (IER) diet. A search was conducted in MEDLINE, EMBASE, AMED, CINAHL and Cochrane library for original research articles investigating the use of very low calorie diets (VLCD) in people with T2DM. The search terms used included "VLCD" or "very low energy diet" or "very low energy restriction" or "IER" or "intermittent fasting" or "calorie restriction" or "diabetes mellitus type 2" and "type 2 diabetes". Reference lists of selected articles were also screened for relevant publications. Only research articles written in English, which also included an explanation of medication changes were included. A recent pilot trial using the 5:2 IER method, conducted by our research group, will also be summarized. A total of 8 studies were found that investigated the use of VLCD in T2DM and discussed medication management. Overall these studies indicate that the use of a VLCD for people with T2DM usually require the cessation of medication to prevent hypoglycemia. Therefore, the 5:2 IER method will also require medication changes, but as seen in our pilot trial, may not require total cessation of medication, rather a cessation on the 2 IER days only. Guidelines outlined here can be used in the initial stages of a 2-d IER diet, but extensive blood glucose monitoring is still required to make the necessary individual reductions to medications in response to weight loss.

  1. Mechanical characterization of the Varian Exact-arm and R-arm support systems for eight aS500 electronic portal imaging devices

    International Nuclear Information System (INIS)

    Grattan, Mark W. D.; McGarry, Conor K.

    2010-01-01

    Purpose: The aim of this study is to compare the positioning accuracy at different gantry angles of two electronic portal imaging devices (EPIDs) support arm systems by using EPID difference images as a measure for displacement. This work presents a comparison of the mechanical performance of eight Varian aS500 (Varian Medical Systems, Palo Alto, CA) EPIDs, mounted using either the Varian Exact-arm or R-arm. Methods: The mechanical performance of the two arm systems was compared by investigating the variation in sensitivity with gantry angle, both before and after the EPID position was adjusted after gantry rotation. Positional errors were investigated by subtracting images from a reference image taken at gantry 0 deg., and the amplitude of the peaks and troughs at the field edges for longitudinal (radial) and lateral (transverse) profiles across the resulting image was related to the distance of displacement. Calibration curves based on a pixel-by-pixel shift were generated for each EPID and the Varian hand pendant accuracy was compared to the calibration data. Results: The response of the EPIDs was found to change with gantry rotation, with the largest difference at 180 deg. The Exact-arm was found to correct well for any displacement, while the R-arm tended to overcorrect following repositioning using the hand pendant. The calibration curves were consistent within each set of matched linacs, and the hand pendant accuracy was similar for both arm systems, although generally in different directions. With respect to gantry rotation effects, the mechanical performance of the Exact-arm systems was found to be much better than that of the R-arm systems. At gantry positions 90 deg., 270 deg., and 180 deg. the average misalignment in the longitudinal direction was +4.2±0.2, +1.8±1.6, and +7.4±0.5 mm for the R-arms, and +2.9±0.2, +2.1±0.8, and +4.9±0.7 mm for the Exact-arms. In the lateral direction the average positional errors were +2.1±0.4, -4.7±0.4, and -2.5

  2. The evaluation for the usability of the Varian Standard Couch modelingusing Treatment Planning System

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Yong Mo; Song, Yong Min; Kim, Jin Man; Choi, Ji Min; Choi, Byeung Gi [Dept. of Radiation Oncology, Samsung Medical Center, Seoul (Korea, Republic of)

    2016-06-15

    When a radiation treatment, there is an attenuation by Carbon Fiber Couch. In this study, we tried to evaluate the usability of the Varian Standard Couch(VSC) by modeling with Treatment Planning System (TPS) VSC was scanned by CBCT(Cone Beam Computed Tomography) of the Linac(Clinac IX, VARIAN, USA), following the three conditions of VSC, Side Rail OutGrid(SROG), Side Rail InGrid(SRIG), Side Rail In OutSpine Down Bar(SRIOS). After scan, the data was transferred to TPS and modeled by contouring Side Rail, Side Bar Upper, Side Bar Lower, Spine Down Bar automatically. We scanned the Cheese Phantom(Middelton, USA) using Computed Tomography(Light Speed RT 16, GE, USA) and transfer the data to TPS, and apply VSC modeled previously with TPS to it. Dose was measured at the isocenter of Ion Chamber(A1SL, Standard imaging, USA) in Cheese Phantom using 4 and 10 MV radiation for every 5° gantry angle in a different filed size(3 X 3 cm{sup 2},10 X 10cm{sup 2}) without any change of MU(=100), and then we compared the calculated dose and measured dose. Also we included dose at the 127° in SRIG to compare the attenuation by Side Bar Upper. Results : The density of VSC by CBCT in TPS was 0.9g/cm{sup 3}, and in the case of Spine Down Bar, it was 0.7g/cm{sup 3}. The radiation was attenuated by 17.49%, 16.49%, 8.54%, and 7.59% at the Side Rail, Side Bar Upper, Side Bar Lower, and Spine Down Bar. For the accuracy of modeling, calculated dose and measured dose were compared. The average error was 1.13% and the maximum error was 1.98% at the 170° beam crossing the Spine Down Bar. To evaluate the usability for the VSC modeled by TPS, the maximum error was 1.98% as a result of compassion between calculated dose and measured dose. We found out that VSC modeling helped expect the dose, so we think that it will be helpful for the more accurate treatment.

  3. Energy expenditure, aerodynamics and medical problems in cycling. An update.

    Science.gov (United States)

    Faria, I E

    1992-07-01

    The cyclist's ability to maintain an extremely high rate of energy expenditure for long durations at a high economy of effort is dependent upon such factors as the individual's anaerobic threshold, muscle fibre type, muscle myoglobin concentration, muscle capillary density and certain anthropometric dimensions. Although laboratory tests have had some success predicting cycling potential, their validity has yet to be established for trained cyclists. Even in analysing the forces producing propulsive torque, cycling effectiveness cannot be based solely on the orientation of applied forces. Innovations of shoe and pedal design continue to have a positive influence on the biomechanics of pedalling. Although muscle involvement during a complete pedal revolution may be similar, economical pedalling rate appears to differ significantly between the novice and racing cyclist. This difference emanates, perhaps, from long term adaptation. Air resistance is by far the greatest retarding force affecting cycling. The aerodynamics of the rider and the bicycle and its components are major contributors to cycling economy. Correct body posture and spacing between riders can significantly enhance speed and efficiency. Acute and chronic responses to cycling and training are complex. To protect the safety and health of the cyclist there must be close monitoring and cooperation between the cyclist, coach, exercise scientist and physician.

  4. Experimental study of the energy efficiency of an incinerator for medical waste

    International Nuclear Information System (INIS)

    Bujak, J.

    2009-01-01

    The aim of this paper is to explore the flux of usable energy and the coefficient of energy efficiency of an incinerator for medical waste combustion. The incineration facility incorporates a heat recovery system. The installation consists of a loading unit, a combustion chamber, a thermoreactor chamber, and a recovery boiler. The analysis was carried out in the Oncological Hospital in Bydgoszcz (Poland). The primary fuel was comprised of medical waste, with natural gas used as a secondary fuel. The study shows that one can obtain about 660-800 kW of usable energy from 100 kg of medical waste. This amount corresponds to 1000-1200 kg of saturated steam, assuming that the incinerator operates at a heat load above φ > 65%. The average heat flux in additional fuel used for incinerating 100 kg of waste was 415 kW. The coefficient of energy efficiency was set within the range of 47% and 62% depending on the incinerator load. The tests revealed that the flux of usable energy and the coefficient of energy efficiency depend on the incinerator load. In the investigated range of the heat load, this dependence is significant. When the heat load of the incinerator increases, the flux of usable energy and the coefficient of energy efficiency also increase.

  5. Generalized monitor unit calculation for the Varian enhanced dynamic wedge field

    International Nuclear Information System (INIS)

    Liu Chihray; Kim, Siyong; Kahler, Darren L.; Palta, Jatinder R.

    2003-01-01

    The generalized monitor unit (MU) calculation equation for the Varian enhanced dynamic wedge (EDW) is derived. The assumption of this MU calculation method is that the wedge factor of the EDW at the center of the field is a function of field size, the position of the center of the field in the wedge direction, and the final position of the moving jaw. The wedge factors at the center of the field in both symmetric and asymmetric fields are examined. The difference between calculated and measured wedge factors is within 1.0%. The method developed here is easy to implement. The only datum required in addition to the standard set of conventional physical wedge implementation data is the off-axis output factor for the open field in the reference condition. The off-center point calculation is also examined. For the off-center point calculation, the dose profile in the wedge direction for the largest EDW field is used to obtain the relative off-center ratio in any smaller wedge field. The accuracy of the off-center point calculation decreases when the point of calculation is too close to the field edge

  6. Assessment of pattern for consumption and awareness regarding energy drinks among medical students.

    Science.gov (United States)

    Aslam, Hafiz Muhammad; Mughal, Anum; Edhi, Muhammad Muzzammil; Saleem, Shafaq; Rao, Masood Hussain; Aftab, Anum; Hanif, Maliha; Ahmed, Alina; Khan, Agha Muhammad Hammad

    2013-01-01

    Energy drink is a type of beverage which contains stimulant drugs chiefly caffeine and marketed as mental and physical stimulator. Coffee, tea, soft drinks and other caffeinated beverages are not considered as energy drinks. Purpose of our study was to evaluate the awareness of medical students regarding energy drinks and their pattern and reason of energy drinks consumption. This was a cross sectional and observational study conducted during the period of January - December 2012 at four Medical Colleges (Dow Medical College, Sindh Medical College, Jinnah Medical College and Liaquat National Medical College) of Karachi, Pakistan. Over all 900 M.B.B.S students were invited to participate after taking written consent but viable questionnaire was submitted by 866 students, estimated response rate of 96%. All data was entered and analyzed through SPSS version 19. Out of 866 participants, majority were females 614 (70.9%) and only 252 (28.5%) were males, with a mean age of 21.43 ± 1.51 years. Energy drinks users were 350 (42.89%) and non users were 516 (59.58%). Only 102 (29.3%) users and 159 (30.7%) non users know the correct definition of Energy drinks. Regarding awareness, mostly user and non users thought that usage of energy drinks had been on rise due to its usefulness in reducing sleep hours [users193 (43.9%), nonusers 247 (56.1%) (p energy drinks by non-users were "awareness from its side effects" 247 (47.8%) and "have no specific reason" 265 (51.3%). Most common side effects reported by users were fatigue 111 (31.7%) and weight gain 102 (29.4%). In sum, the fact that despite serious side effects of weight gaining and fatigue, practice of consuming energy drinks is highly prevalent among medical students, particularly because they are ever ready to boost their energy level and reduce sleep hours due to stress of exams and projects. This warrants the creation of continued public health awareness about the appropriate use of caffeinated beverages, their

  7. Medical physics in Europe following recommendations of the International Atomic Energy Agency

    International Nuclear Information System (INIS)

    Casar, Bozidar; Lopes, Maria do Carmo; Drljević, Advan; Gershkevitsh, Eduard; Pesznyak, Csilla

    2016-01-01

    Medical physics is a health profession where principles of applied physics are mostly directed towards the application of ionizing radiation in medicine. The key role of the medical physics expert in safe and effective use of ionizing radiation in medicine was widely recognized in recent European reference documents like the European Union Council Directive 2013/59/EURATOM (2014), and European Commission Radiation Protection No. 174, European Guidelines on Medical Physics Expert (2014). Also the International Atomic Energy Agency (IAEA) has been outspoken in supporting and fostering the status of medical physics in radiation medicine through multiple initiatives as technical and cooperation projects and important documents like IAEA Human Health Series No. 25, Roles and Responsibilities, and Education and Training Requirements for Clinically Qualified Medical Physicists (2013) and the International Basic Safety Standards, General Safety Requirements Part 3 (2014). The significance of these documents and the recognition of the present insufficient fulfilment of the requirements and recommendations in many European countries have led the IAEA to organize in 2015 the Regional Meeting on Medical Physics in Europe, where major issues in medical physics in Europe were discussed. Most important outcomes of the meeting were the recommendations addressed to European member states and the survey on medical physics status in Europe conducted by the IAEA and European Federation of Organizations for Medical Physics. Published recommendations of IAEA Regional Meeting on Medical Physics in Europe shall be followed and enforced in all European states. Appropriate qualification framework including education, clinical specialization, certification and registration of medical physicists shall be established and international recommendation regarding staffing levels in the field of medical physics shall be fulfilled in particular. European states have clear legal and moral

  8. Medical physics in Europe following recommendations of the International Atomic Energy Agency.

    Science.gov (United States)

    Casar, Bozidar; Lopes, Maria do Carmo; Drljević, Advan; Gershkevitsh, Eduard; Pesznyak, Csilla

    2016-03-01

    Medical physics is a health profession where principles of applied physics are mostly directed towards the application of ionizing radiation in medicine. The key role of the medical physics expert in safe and effective use of ionizing radiation in medicine was widely recognized in recent European reference documents like the European Union Council Directive 2013/59/EURATOM (2014), and European Commission Radiation Protection No. 174, European Guidelines on Medical Physics Expert (2014). Also the International Atomic Energy Agency (IAEA) has been outspoken in supporting and fostering the status of medical physics in radiation medicine through multiple initiatives as technical and cooperation projects and important documents like IAEA Human Health Series No. 25, Roles and Responsibilities, and Education and Training Requirements for Clinically Qualified Medical Physicists (2013) and the International Basic Safety Standards, General Safety Requirements Part 3 (2014). The significance of these documents and the recognition of the present insufficient fulfilment of the requirements and recommendations in many European countries have led the IAEA to organize in 2015 the Regional Meeting on Medical Physics in Europe, where major issues in medical physics in Europe were discussed. Most important outcomes of the meeting were the recommendations addressed to European member states and the survey on medical physics status in Europe conducted by the IAEA and European Federation of Organizations for Medical Physics. Published recommendations of IAEA Regional Meeting on Medical Physics in Europe shall be followed and enforced in all European states. Appropriate qualification framework including education, clinical specialization, certification and registration of medical physicists shall be established and international recommendation regarding staffing levels in the field of medical physics shall be fulfilled in particular. European states have clear legal and moral

  9. Medical physics in Europe following recommendations of the International Atomic Energy Agency

    Science.gov (United States)

    Lopes, Maria do Carmo; Drljević, Advan; Gershkevitsh, Eduard; Pesznyak, Csilla

    2016-01-01

    Background Medical physics is a health profession where principles of applied physics are mostly directed towards the application of ionizing radiation in medicine. The key role of the medical physics expert in safe and effective use of ionizing radiation in medicine was widely recognized in recent European reference documents like the European Union Council Directive 2013/59/EURATOM (2014), and European Commission Radiation Protection No. 174, European Guidelines on Medical Physics Expert (2014). Also the International Atomic Energy Agency (IAEA) has been outspoken in supporting and fostering the status of medical physics in radiation medicine through multiple initiatives as technical and cooperation projects and important documents like IAEA Human Health Series No. 25, Roles and Responsibilities, and Education and Training Requirements for Clinically Qualified Medical Physicists (2013) and the International Basic Safety Standards, General Safety Requirements Part 3 (2014). The significance of these documents and the recognition of the present insufficient fulfilment of the requirements and recommendations in many European countries have led the IAEA to organize in 2015 the Regional Meeting on Medical Physics in Europe, where major issues in medical physics in Europe were discussed. Most important outcomes of the meeting were the recommendations addressed to European member states and the survey on medical physics status in Europe conducted by the IAEA and European Federation of Organizations for Medical Physics. Conclusions Published recommendations of IAEA Regional Meeting on Medical Physics in Europe shall be followed and enforced in all European states. Appropriate qualification framework including education, clinical specialization, certification and registration of medical physicists shall be established and international recommendation regarding staffing levels in the field of medical physics shall be fulfilled in particular. European states have clear

  10. Energy drinks consumption practices among medical students of a Private sector University of Karachi, Pakistan.

    Science.gov (United States)

    Usman, Asma; Bhombal, Swaleha Tariq; Jawaid, Ambreen; Zaki, Samar

    2015-09-01

    Consumption of energy drinks has become popular among students and athletes over the past few years. To explore the phenomenon, a cross-sectional survey was conducted through a self-administered pilot-tested questionnaire. Frequency of energy drinks consumption was found to be 121(52%) in a sample of 233 medical students. Red bull was the most common brand consumed 101(43%). The major reasons reported for its usage were to gain/replenish energy by 36(15.4%), and studying for examination by 34(14.6%). Television was reported as the major source of information 153(66%) followed by friends 113(48%). There was a high frequency of energy drinks' consumption among medical students of a private university. There is a strong need to create awareness regarding these drinks, especially among adolescents and teenagers.

  11. Performance studies of varian VPM-154D.6D VPM-154A/1.6L static crossed field photomultipliers

    International Nuclear Information System (INIS)

    Lo, C.C.; Leskovar, B.

    1977-01-01

    Characteristics have been measured for the Varian VPM-154D.6D and VPM-154A/1.6L Static Crossed Field Photomultipliers. Some typical photomultiplier characteristics such as: gain, dark current, quantum efficiency, and rise-time--are compared with data provided by the manufacturer. Photomultiplier characteristics generally not available from the manufacturer, such as: transit time, FWHM of the output pulse, peak output current measurement and multiphotoelectron time resolution were measured and are discussed

  12. Assessment of dosimetrical performance in 11 Varian a-Si500 electronic portal imaging devices

    International Nuclear Information System (INIS)

    Kavuma, Awusi; Glegg, Martin; Currie, Garry; Elliott, Alex

    2008-01-01

    Dosimetrical characteristics of 11 Varian a-Si-500 electronic portal imaging devices (EPIDs) in clinical use for periods ranging between 10 and 86 months were investigated for consistency of performance and portal dosimetry implications. Properties studied include short-term reproducibility, signal linearity with monitor units, response to reference beam, signal uniformity across the detector panel, signal dependence on field size, dose-rate influence, memory effects and image profiles as a function of monitor units. The EPID measurements were also compared with those of the ionization chambers' to ensure stability of the linear accelerators. Depending on their clinical installation date, the EPIDs were interfaced with one of the two different acquisition control software packages, IAS2/IDU-II or IAS3/IDU-20. Both the EPID age and image acquisition system influenced the dosimetric characteristics with the newer version (IAS3 with IDU-20) giving better data reproducibility and linearity fit than the older version (IAS2 with IDU-II). The relative signal response (uniformity) after 50 MU was better than 95% of the central value and independent of detector. Sensitivity for all EPIDs reduced continuously with increasing dose rates for the newer image acquisition software. In the dose-rate range 100-600 MU min -1 , the maximum variation in sensitivity ranged between 1 and 1.8% for different EPIDs. For memory effects, the increase in the measured signal at the centre of the irradiated field for successive images was within 1.8% and 1.0% for the older and newer acquisition systems, respectively. Image profiles acquired at a lower MU in the radial plane (gun-target) had gradients in measured pixel values of up to 25% for the older system. Detectors with software/hardware versions IAS3/IDU-20 have a high degree of accuracy and are more suitable for routine quantitative IMRT dosimetrical verification.

  13. Recent topical research on global, energy, health & medical, and tourism economics, and global software: An overview

    NARCIS (Netherlands)

    C-L. Chang (Chia-Lin); M.J. McAleer (Michael)

    2017-01-01

    textabstractThe paper presents an overview of recent topical research on global, energy, health & medical, and tourism economics, and global software. We have interpreted "global" in the title of the Journal of Reviews on Global Economics to cover contributions that have a global impact on

  14. Recent Topical Research on Global, Energy, Health & Medical, and Tourism Economics, and Global Software

    NARCIS (Netherlands)

    C-L. Chang (Chia-Lin); M.J. McAleer (Michael)

    2017-01-01

    textabstractThe paper presents an overview of recent topical research on global, energy, health & medical, and tourism economics, and global software. We have interpreted “global” in the title of the Journal of Reviews on Global Economics to cover contributions that have a global impact on

  15. Teaching Energy Metabolism Using Scientific Articles: Implementation of a Virtual Learning Environment for Medical Students

    Science.gov (United States)

    de Espindola, Marina Bazzo; El-Bacha, Tatiana; Giannella, Tais Rabetti; Struchiner, Miriam; da Silva, Wagner S.; Da Poian, Andrea T.

    2010-01-01

    This work describes the use of a virtual learning environment (VLE) applied to the biochemistry class for undergraduate, first-year medical students at the Federal University of Rio de Janeiro. The course focused on the integration of energy metabolism, exploring metabolic adaptations in different physiological or pathological states such as…

  16. Portal imaging improvement with a low energy un flattened beam in high energy medical accelerators

    Energy Technology Data Exchange (ETDEWEB)

    Krutman, Y; Faermann, S; Tsechanski, A [Ben-Gurion Univ. of the Negev, Beersheba (Israel)

    1996-12-01

    In this work we present a further improvement of the portal film option, for a Clinac 18 accelerator with a 10 MV therapeutic x-ray beam. This is done by lowering the nominal photon energy to 4 MV, therefore increasing the relative contribution of the low energy portion of the x-ray spectrum. Improvement of the image quality is demonstrated with a portal film scale tray, and with an anthropomorphic phantom, a graphical analysis demonstrates the improvement on image (authors).

  17. PENJADWALAN JOBS PADA SINGLE MACHINE DENGAN MEMINIMUMKAN VARIANS WAKTU PENYELESAIAN JOBS Studi Kasus di P.T. XYZ

    Directory of Open Access Journals (Sweden)

    I Nyoman Sutapa

    2001-01-01

    Full Text Available This paper discusses a jobs scheduling on a single machine to minimize variance of job completion time. The objective is especially important in situations where it is desirable to provide customers or jobs with approximately the same treatment. In this case, data are collected from P.T. 'XYZ'. The focus of discussion is LB/KB Departement (Leather Board/Carton Board with carton board's production line, which produces carton board. Carton board's size is 150 x 110 cm and its thickness from 0,6 mm to 2,5 mm. In this paper a comparison analysis, the deviation of the objective value given by a heuristic (Vh method from the objective value given by P.T. 'XYZ' (Vp, is made. The percentage of deviation Vh from Vp is 50,36 %, which shows that the performance of heuristic is better, that is variance of job completion time by heuristic method smaller than by P.T. 'XYZ'. Besides the above discussion, the weakness dan superiority of heuristic are analyzed too. Abstract in Bahasa Indonesia : Makalah ini membahas penjadwalan jobs pada single machine dengan tujuan meminimumkan varians waktu penyelesaian job, yaitu untuk memberikan konsumen atau jobs kurang lebih perlakuan yang sama. Data yang diambil dalam pembahasan ini berasal dari perusahaan P.T. 'XYZ', di mana departemen yang menjadi fokus pembahasan adalah Departemen LB/KB (Leather Board/Karton Board dengan lintasan produksi karton board yang menghasilkan produk carton board ukuran 150 x 110 cm, dengan ketebalan 0,6 mm sampai dengan 2,5 mm. Dalam makalah ini dilakukan analisis perbandingan jadwal jobs pada proses produksi di perusahaan yang telah ada dengan jadwal jobs menggunakan metode heuristic, yaitu menggunakan persentase penyimpangan Vh (varians waktu penyelesaian jobs metode heuristic dari Vp (varians waktu penyelesaian jobs perusahaan. Dari hasil analisis didapatkan bahwa persentase penyimpangan Vh dari Vp sebesar 50,36%, hal ini menunjukkan bahwa performance metode heuristic lebih baik, yaitu

  18. TU-F-CAMPUS-T-01: Dose and Energy Spectra From Neutron Induced Radioactivity in Medical Linear Accelerators Following High Energy Total Body Irradiation

    International Nuclear Information System (INIS)

    Keehan, S; Taylor, M; Franich, R; Smith, R; Dunn, L; Kron, T

    2015-01-01

    Purpose: To assess the risk posed by neutron induced activation of components in medical linear accelerators (linacs) following the delivery of high monitor unit 18 MV photon beams such as used in TBI. Methods: Gamma spectroscopy was used to identify radioisotopes produced in components of a Varian 21EX and an Elekta Synergy following delivery of photon beams. Dose and risk estimates for TBI were assessed using dose deliveries from an actual patient treatment. A 1 litre spherical ion chamber (PTW, Germany) has been used to measure the dose at the beam exit window and at the total body irradiation (TBI) treatment couch following large and small field beams with long beam-on times. Measurements were also made outside of the closed jaws to quantify the benefit of the attenuation provided by the jaws. Results: The radioisotopes produced in the linac head have been identified as 187 W, 56 Mn, 24 Na and 28 Al, which have half-lives from between 2.3 min to 24 hours. The dose at the beam exit window following an 18 MV 2197 MU TBI beam delivery was 12.6 µSv in ten minutes. The dose rate at the TBI treatment couch 4.8 m away is a factor of ten lower. For a typical TBI delivered in six fractions each consisting of four beams and an annual patient load of 24, the annual dose estimate for a staff member at the treatment couch for ten minutes is 750 µSv. This can be further reduced by a factor of about twelve if the jaws are closed before entering the room, resulting in a dose estimate of 65 µSv. Conclusion: The dose resulting from the activation products for a representative TBI workload at our clinic of 24 patients per year is 750 µSv, which can be further reduced to 65 µSv by closing the jaws

  19. SU-F-BRE-11: Neutron Measurements Around the Varian TrueBeam Linac

    Energy Technology Data Exchange (ETDEWEB)

    Maglieri, R; Seuntjens, J; Kildea, J [McGill University, Montreal, QC (Canada); Liang, L; DeBlois, F [Jewish General Hospital, Montreal, QC (Canada); Evans, M [Montreal General Hospital, Montreal, QC (Canada); Licea, A [Canadian Nuclear Safety Comission, Ottawa, Ontario (Canada); Dubeau, J; Witharana, S [Detec, Gatineau, QC (Canada)

    2014-06-15

    Purpose: With the emergence of flattening filter free (FFF) photon beams, several authors have noted many advantages to their use. One such advantage is the decrease in neutron production by photonuclear reactions in the linac head. In the present work we investigate the reduction in neutrons from a Varian TrueBeam linac using the Nested Neutron Spectrometer (NNS, Detec). The neutron spectrum, total fluence and source strength were measured and compared for 10 MV with and without flattening filter and the effect of moderation by the room and maze was studied for the 15 MV beam. Methods: The NNS, similar to traditional Bonner sphere detectors but operated in current mode, was used to measure the neutron fluence and spectrum. The NNS was validated for use in high dose rate environments using Monte Carlo simulations and calibrated at NIST and NRC Canada. Measurements were performed at several positions within the treatment room and maze with the linac jaws closed to maximize neutron production. Results: The measurements showed a total fluence reduction between 35-40% in the room and maze when the flattening filter was removed. The neutron source strength Qn was calculated from in-room fluence measurements and was found to be 0.042 × 10{sup 2} n/Gy, 0.026 × 10{sup 2} n/Gy and 0.59 × 101{sup 2} n/Gy for the 10 MV, the 10 MV FFF and 15 MV beams, respectively. We measured ambient equivalent doses of 11 mSv/hr, 7 mSv/hr and 218 mSv/hr for the 10 MV, 10 MV FFF and 15 MV by the head. Conclusion: Our measurements revealed a decrease in total fluence, neutron source strength and equivalent dose of approximately 35-40% across the treatment room for the FFF compared to FF modes. This demonstrates, as expected, that the flattening filter is a major component of the neutron production for the TrueBeam. The authors greatly acknowledge support form the Canadian Nuclear Commission and the Natural Sciences and Engineering Research Council of Canada through the CREATE program. Co

  20. A quality control method for detecting energy changes of medical accelerators

    International Nuclear Information System (INIS)

    McGinley, P.H.

    2000-01-01

    A description is presented of a simple and sensitive method for detecting a change in the energy of the electrons bombarding the target of medical accelerators. This technique is useful for x-ray beams with end point energy in the range of 15.7 to 25 MeV. The method is based on the photoactivation of 16 O and 14 N in a small sample of ammonium nitrate. It was found that the ratio of the activity induced in the oxygen divided by that produced in the nitrogen can be used as a quality control technique to detect a change in the energy of the electrons that bombard the target of the accelerator. An electron energy change of the order of 0.2 MeV can be determined using this method. (author)

  1. An energy-subtraction Compton scatter camera design for in vivo medical imaging of radiopharmaceuticals

    International Nuclear Information System (INIS)

    Rohe, R.C.; Valentine, J.D.

    1996-01-01

    A Compton scatter camera (CSC) design is proposed for imaging radioisotopes used as biotracers. A clinical version may increase sensitivity by a factor of over 100, while maintaining or improving spatial resolution, as compared with existing Anger cameras that use lead collimators. This novel approach is based on using energy subtraction (ΔE = E 0 - E SC , where E 0 , ΔE, and E SC are the energy of the emitted gamma ray, the energy deposited by the initial Compton scatter, and the energy of the Compton scattered photon) to determine the amount of energy deposited in the primary system. The energy subtraction approach allows the requirement of high energy resolution to be placed on a secondary detector system instead of the primary detector system. Requiring primary system high energy resolution has significantly limited previous CSC designs for medical imaging applications. Furthermore, this approach is dependent on optimizing the camera design for data acquisition of gamma rays that undergo only one Compton scatter in a low-Z primary detector system followed by a total absorption of the Compton scattered photon in a high-Z secondary detector system. The proposed approach allows for a more compact primary detector system, a more simplified pulse processing interface, and a much less complicated detector cooling scheme as compared with previous CSC designs. Analytical calculations and Monte Carlo simulation results for some specific detector materials and geometries are presented

  2. Dissemination of medical applications of nuclear energy with virtual reality technology

    International Nuclear Information System (INIS)

    Botelho, Felipe M.; Oliveira, Beatriz A.R.

    2007-01-01

    This work makes use of Virtual Reality technology to disseminate medical applications of nuclear energy, with educational purposes. Virtual Reality is an effective learning tool, since navigation and interaction in virtual worlds can improve motivation in the learning process. With this technology, learning can be achieved in a clearer, joyful and more objective way. Among the existing medical applications of nuclear energy, this work focuses on the use of radiopharmaceuticals. The goal is to simulate this application in a virtual environment, for educational purposes, and to show the absorption of a radiopharmaceutical by the human body, during a diagnostics or treatment procedure. An example has been chosen, for Iodine radiopharmaceutical, which has affinity with the thyroid, and then concentrates in this organ. During the simulation, the concentration of the radioactive Iodine in the thyroid can be emphasized, and in the sequence, the virtual patient can be shown during the imaging procedure. (author)

  3. Technical assistance for Meharry Medical College Energy Efficiency Project. Final project status and technical report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-05-08

    This report presents the results of a program to provide technical assistance to Meharry Medical College. The purpose of the program is to facilitate Meharry`s effort to finance a campus-wide facility retrofit. The US Department of Energy (USDOE) funded the program through a grant to the Tennessee Department of Economic and Community Development (TECD). The University of Memphis-Technology and Energy Services (UM-TES), under contract to TECD, performed program services. The report has three sections: (1) introduction; (2) project definition, financing, and participants; and (3) opportunities for federal participation.

  4. Radiological and Medical Sciences Research Institute, Ghana Atomic Energy Commission: Annual Report 2014

    International Nuclear Information System (INIS)

    2014-01-01

    The Radiological and Medical Sciences Research Institute was established in 2009, as the forth research institute of the Ghana Atomic Energy Commission. This Annual Report provides an overview of the major activities of the Institutes in the year 2014. Major items covered in the report include: Strategic objectives; Collaborations; Personnel and Organisational Structure; Facilities and Technical Services; Summary of Research and Development Projects; Human Resource Development; Publications and Technical Reports.

  5. Efforts made for health and medical care by International Atomic Energy Agency

    International Nuclear Information System (INIS)

    Watanabe, Naoyuki

    2016-01-01

    The author, being a former senior medical officer and currently a consultant of the Nuclear Medicine Section, the Division of Human Health, the Department of Nuclear Sciences and Applications, the International Atomic Energy Agency (IAEA) to standardize the isotope and radiation technologies for health and medical care and transfer them to the IAEA member states to address their health issues, participated in an international cooperation project to survey the current situation of the health and medical care in Viet Nam and exchange opinions with the World Health Organization Western Pacific Regional Office Viet Nam Office and the Viet Nam Health Department coordinated by the Japan Public Health Association from 10th to 15th January 2016 and perceived efforts made and action plans for the health and medical care in Viet Nam by the international organizations of the IAEA and the World Health Organization (WHO). IAEA has verified various isotopes and radiation technologies up to now in the international field of health and medical care and has being offered them to the member states under the sustainable frame work of technical co-operation. However, the activity in the health and medical care field of IAEA is hardly recognized by the public health professionals in Japan. In order to attain the objective to improve and maintain human health under the umbrella of the United Nations system, the peaceful use of nuclear technology has been promoted in the field of non-electric applications of nuclear energy including human health and medical care by the IAEA. There are several discrepancies seen with the field and tactics of health and medical care between the IAEA and the WHO. In terms of measures to fight NCDs which should be an urgent issue in most of the member states, a comprehensive approach is often needed beyond the capability of IAEA as isotopes and radiation technologies. The IAEA should strive to solve issues on human health and medical care maintaining much

  6. Poster — Thur Eve — 55: An automated XML technique for isocentre verification on the Varian TrueBeam

    International Nuclear Information System (INIS)

    Asiev, Krum; Mullins, Joel; DeBlois, François; Liang, Liheng; Syme, Alasdair

    2014-01-01

    Isocentre verification tests, such as the Winston-Lutz (WL) test, have gained popularity in the recent years as techniques such as stereotactic radiosurgery/radiotherapy (SRS/SRT) treatments are more commonly performed on radiotherapy linacs. These highly conformal treatments require frequent monitoring of the geometrical accuracy of the isocentre to ensure proper radiation delivery. At our clinic, the WL test is performed by acquiring with the EPID a collection of 8 images of a WL phantom fixed on the couch for various couch/gantry angles. This set of images is later analyzed to determine the isocentre size. The current work addresses the acquisition process. A manual WL test acquisition performed by and experienced physicist takes in average 25 minutes and is prone to user manipulation errors. We have automated this acquisition on a Varian TrueBeam STx linac (Varian, Palo Alto, USA). The Varian developer mode allows the execution of custom-made XML script files to control all aspects of the linac operation. We have created an XML-WL script that cycles through each couch/gantry combinations taking an EPID image at each position. This automated acquisition is done in less than 4 minutes. The reproducibility of the method was verified by repeating the execution of the XML file 5 times. The analysis of the images showed variation of the isocenter size less than 0.1 mm along the X, Y and Z axes and compares favorably to a manual acquisition for which we typically observe variations up to 0.5 mm

  7. Recovering traditional raw-milk Tetilla cheese flavour and sensory attributes by using Kocuria varians and Yarrowia lipolytica adjunct cultures.

    Science.gov (United States)

    Centeno, J A; Garabal, J I; Docampo, F; Lorenzo, J M; Carballo, J

    2017-06-19

    The rationale of the present study was to evaluate the potential of microbial adjunct cultures including Kocuria varians and/or Yarrowia lipolytica strains in the recovery of the typical sensory profile of traditional (raw-milk) Tetilla cheese. Four batches of Tetilla cheese, a short ripened cows' milk cheese produced in Galicia (NW Spain), were made in duplicate from pasteurized milk inoculated with different microbial cultures. A control batch was manufactured by adding a mesophilic commercial D-starter only. The other three batches were made with the same starter after a cheese-milk pre-ripening step carried out with (i) an adjunct culture of K. varians, (ii) an adjunct culture of Y. lipolytica, or (iii) a combination of both adjunct cultures. The highest pH and water activity values, associated with softer textures were determined in the cheeses manufactured with the Y. lipolytica adjunct after 21days of ripening. The contents of the volatile compounds 3-methylbutanol, dimethyl disulfide and dimethyl trisulfide were higher in the cheeses made with only the K. varians adjunct than in the cheeses made with the only yeast adjunct and in the control cheeses. The contents of hexanoic and octanoic acids were highest in the cheeses made with the Y. lipolytica adjunct, and levels of ethyl hexanoate, ethyl octanoate and ethyl decanoate were higher in the cheeses made with only the yeast adjunct than in the other batches of cheese. The cheeses manufactured with both adjunct cultures were awarded the highest scores for flavour and overall sensory parameters (considering the standards of the traditional product) and were considered very similar to 'good quality' artisanal raw-milk cheeses. We conclude that use of selected Micrococcaceae and Y. lipolytica strains as adjunct cultures would differentiate the sensory properties and contribute to the quality and typicality of the short-ripened rennet-curd Galician Tetilla and Arzúa-Ulloa cheeses. Copyright © 2017 Elsevier B

  8. SU-E-T-06: A Comparison of IMRT Treatment of Esophageal Carcinoma in Elekta-Precise and Varian23EX Linac

    Energy Technology Data Exchange (ETDEWEB)

    Bai, W; Fan, X; Qiu, R; Qiao, X; Zhang, R [Hebei Medical University Fourth Hospital, Shijiazhuang, Hebei (China)

    2014-06-01

    Purpose: To compare and analyze the characteristics of static intensity-modulated radiotherapy (IMRT) plans designed on Elekta and Varian Linac in different esophageal cancer(EC), exploring advantages and disadvantages of different vendor Linac, thus can be better serve for clinical. Methods: Twenty-four patients with EC were selected, including 6 cases located in the cervical, upper, middle and the lower thorax, respectively. Two IMRT plans were generated with the Oncentra planning system: in Elekta and Varian Linac, prescription dose of 60Gy in 30 fractions to the PTV. We examined the dose-volume histogram parameters of PTV and the organs at risk (OAR) such as lungs, spinal cord and heart, and additional Monitor units(MU), treatment time, Homogeneity index(HI), Conformity index(CI) and Gamma index comparisons were performed. Results: All plans resulted in abundant dose coverage of PTV for EC of different locations. The doses to PTV, HI and OAR in Elekta plans were not statistically different in comparison with Varian plans, with the following exceptions: in cervical, upper and lower thoracic EC the PTV's CI, and in middle thorax EC PTV's D2, D50, V105 and PTV-average were better in Elekta plans than in Varian plans. In the cervical, upper and the middle thorax EC, treatment time were significantly decreased in Varian plans as against Elekta plans, while in the lower thoracic EC treatment time were no striking difference. MUs and gamma index were similar between the two Linac plans. Conclusion: For the the middle thorax EC Varian plans is better than Elekta plans, not only in treatment time but in the PTV dose; while for the lower thorax EC Elekta plans is the first choice for better CI; for the other part of the EC usually Elekta plans can increase the CI, while Varian plans can reduce treatment time, can be selected according to the actual situation of the patient treatment.

  9. Interactions between Lactobacillus sakei and CNC (Staphylococcus xylosus and Kocuria varians) and their influence on proteolytic activity.

    Science.gov (United States)

    Tremonte, P; Reale, A; Di Renzo, T; Tipaldi, L; Di Luccia, A; Coppola, R; Sorrentino, E; Succi, M

    2010-11-01

    To evaluate interactions between Lactobacillus sakei and coagulase negative cocci (CNC) (Staphylococcus xylosus and Kocuria varians) and to investigate the influence of these interactions on their own proteolytic activity. Interactions occurring between strains of Lact. sakei and CNC were assessed by spectrophotometric analysis. The growth of 35 strains of Lact. sakei, used as indicators, was compared to that obtained combining the same strains with growing cells or cell-free supernatants of 20 CNC (18 Staph. xylosus and 2 K. varians). The proteolytic activity expressed by single strains or by their combinations was assessed on sarcoplasmic protein extracts by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The results evidenced that interactions are able to affect not only the growth but also the in vitro proteolytic activity of Lact. sakei and CNC used in combination. A relationship between the presence of interactions among useful strains and the strength of technological characteristics, such as proteolysis, was defined. The study highlighted that CNC are able to stimulate the growth of some Lact. sakei strains. At the same time, this interaction positively influences the proteolytic activity of strains used in combination. Given the importance of proteolysis during the ripening of fermented meats, this phenomenon should be taken into account to select meat starter cultures. © 2010 The Authors. © 2010 The Society for Applied Microbiology.

  10. Log-Gabor Energy Based Multimodal Medical Image Fusion in NSCT Domain

    Directory of Open Access Journals (Sweden)

    Yong Yang

    2014-01-01

    Full Text Available Multimodal medical image fusion is a powerful tool in clinical applications such as noninvasive diagnosis, image-guided radiotherapy, and treatment planning. In this paper, a novel nonsubsampled Contourlet transform (NSCT based method for multimodal medical image fusion is presented, which is approximately shift invariant and can effectively suppress the pseudo-Gibbs phenomena. The source medical images are initially transformed by NSCT followed by fusing low- and high-frequency components. The phase congruency that can provide a contrast and brightness-invariant representation is applied to fuse low-frequency coefficients, whereas the Log-Gabor energy that can efficiently determine the frequency coefficients from the clear and detail parts is employed to fuse the high-frequency coefficients. The proposed fusion method has been compared with the discrete wavelet transform (DWT, the fast discrete curvelet transform (FDCT, and the dual tree complex wavelet transform (DTCWT based image fusion methods and other NSCT-based methods. Visually and quantitatively experimental results indicate that the proposed fusion method can obtain more effective and accurate fusion results of multimodal medical images than other algorithms. Further, the applicability of the proposed method has been testified by carrying out a clinical example on a woman affected with recurrent tumor images.

  11. The FLUKA Code: Developments and Challenges for High Energy and Medical Applications

    CERN Document Server

    Böhlen, T T; Chin, M P W; Fassò, A; Ferrari, A; Ortega, P G; Mairani, A; Sala, P R; Smirnov, G; Vlachoudis, V

    2014-01-01

    The FLUKA Monte Carlo code is used extensively at CERN for all beam-machine interactions, radioprotection calculations and facility design of forthcoming projects. Such needs require the code to be consistently reliable over the entire energy range (from MeV to TeV) for all projectiles (full suite of elementary particles and heavy ions). Outside CERN, among various applications worldwide, FLUKA serves as a core tool for the HIT and CNAO hadron-therapy facilities in Europe. Therefore, medical applications further impose stringent requirements in terms of reliability and predictive power, which demands constant refinement of sophisticated nuclear models and continuous code improvement. Some of the latest developments implemented in FLUKA are presented in this paper, with particular emphasis on issues and concerns pertaining to CERN and medical applications.

  12. Safe Disposal of Medical and Plastic Waste and Energy Recovery Possibilities using Plasma Pyrolysis Technology

    International Nuclear Information System (INIS)

    Nema, S.K.; Mukherjee, S.

    2010-01-01

    Plasma pyrolysis and plasma gasification are emerging technologies that can provide complete solution to organic solid waste disposal. In these technologies plasma torch is used as a workhorse to convert electrical energy into heat energy. These technologies dispose the organic waste in an environment friendly manner. Thermal plasma provides extremely high temperature in oxygen free or controlled air environment which is required for pyrolysis or gasification reactions. Plasma based medical waste treatment is an extremely complex technology since it has to contend with extreme temperatures and corrosion-prone environment, complex pyro-chemistry resulting in toxic and dangerous products, if not controlled. In addition, one has to take care of complete combustion of pyrolyzed gases followed by efficient scrubbing to meet the emission standards set by US EPA and Central Pollution Control Board, India. In medical waste, high volume and low packing density waste with nonstandard composition consisting of a variety of plastics, organic material and liquids used to be present. The present paper describes the work carried out at Institute for Plasma Research, India, on plasma pyrolysis of (i) medical waste disposal and the results of emission measurement done at various locations in the system and (ii) energy recovery from cotton and plastic waste. The process and system development has been done in multiple steps. Different plasma pyrolysis models were made and each subsequent model was improved upon to meet stringent emission norms and to make the system energy efficient and user friendly. FCIPT, has successfully demonstrated up to 50 kg/ hr plasma pyrolysis systems and have installed plasma pyrolysis facilities at various locations in India . Plastic Waste disposal along with energy recovery in 15 kg/ hr model has also been developed and demonstrated at FCIPT. In future, this technology has great potential to dispose safely different waste streams such as biomass

  13. No speed limits in medical imaging and high-energy physics

    CERN Multimedia

    Rita Giuffredi & Tom Meyer

    2015-01-01

    Speed, or high time resolution, is becoming increasingly important, if not crucial, in the high-energy physics domain, both for particle acceleration and detection systems. Medical-imaging technology also vitally depends on high time resolution detection techniques, often the offspring of today’s large particle physics experiments. The four-year FP7 Marie Curie Training Project “PicoSEC-MCNet”, which draws to a close at the end of November, was designed to develop ultra-fast photon detectors for applications in both domains. The project has achieved important results that promise to trigger further developments in the years to come.   The PicoSEC-MCNet project participants. “New requirements in high-energy physics force us to push the limits of photon detection speed, as future high-luminosity accelerators will force us to cope with the unprecedentedly short bunch crossing intervals needed to produce sufficient luminosity,” explains Tom M...

  14. Clinical application of image-guided radiotherapy, IGRT (on the Varian OBI platform); Applications cliniques de la radiotherapie guidee par l'image (RTGI)

    Energy Technology Data Exchange (ETDEWEB)

    Sorcini, B.; Tilikidis, A. [Karolinska Univ. Hospital, Dept. of Medical Physics, Stockholm (Sweden)

    2006-09-15

    Image-guided radiation therapy (IGRT) can be used to measure and correct positional errors for target and critical structures immediately prior to or during treatment delivery. Some of the most recent available methods applied for target localization are: trans-abdominal ultrasound, implanted markers with in room MV or kV X-rays, optical surface tracking systems, implantable electromagnetic markers, in room CT such as kVCT on rail, kilo-voltage or mega-voltage cone-beam CT (CBCT) and helical megavoltage CT. The verification of the accurate treatment position in conjunction with detailed anatomical information before every fraction can be essential for the outcome of the treatment. In this paper we present the on-board imager (OBI, Varian Medical Systems, Palo Alto, CA) that has been in routine clinical use at the Karolinska University Hospital since June 2004. The OBI has been used for on-line set-up correction of prostate patients using internal gold markers. Displacements of these markers can be monitored radiographically during the treatment course and the registered marker shifts act as a surrogate for prostate motion. For this purpose, on-board kV-kV seems to be an ideal system in terms of image quality. The CBCT function of OBI was installed in March 2005 at our department. It focuses on localizing tumors based on internal anatomy, not just on the conventional external marks or tattoos. The CBCT system provides the capacity for soft tissue imaging in the treatment position and real-time radiographic monitoring during treatment delivery. (authors)

  15. An Energy-Efficient ASIC for Wireless Body Sensor Networks in Medical Applications.

    Science.gov (United States)

    Xiaoyu Zhang; Hanjun Jiang; Lingwei Zhang; Chun Zhang; Zhihua Wang; Xinkai Chen

    2010-02-01

    An energy-efficient application-specific integrated circuit (ASIC) featured with a work-on-demand protocol is designed for wireless body sensor networks (WBSNs) in medical applications. Dedicated for ultra-low-power wireless sensor nodes, the ASIC consists of a low-power microcontroller unit (MCU), a power-management unit (PMU), reconfigurable sensor interfaces, communication ports controlling a wireless transceiver, and an integrated passive radio-frequency (RF) receiver with energy harvesting ability. The MCU, together with the PMU, provides quite flexible communication and power-control modes for energy-efficient operations. The always-on passive RF receiver with an RF energy harvesting block offers the sensor nodes the capability of work-on-demand with zero standby power. Fabricated in standard 0.18-¿m complementary metal-oxide semiconductor technology, the ASIC occupies a die area of 2 mm × 2.5 mm. A wireless body sensor network sensor-node prototype using this ASIC only consumes < 10-nA current under the passive standby mode, and < 10 ¿A under the active standby mode, when supplied by a 3-V battery.

  16. David Grant Medical Center energy use baseline and integrated resource assessment

    Energy Technology Data Exchange (ETDEWEB)

    Richman, E.E.; Hoshide, R.K.; Dittmer, A.L.

    1993-04-01

    The US Air Mobility Command (AMC) has tasked Pacific Northwest Laboratory (PNL) with supporting the US Department of Energy (DOE) Federal Energy Management Program`s (FEMP) mission to identify, evaluate, and assist in acquiring all cost-effective energy resource opportunities (EROs) at the David Grant Medical Center (DGMC). This report describes the methodology used to identify and evaluate the EROs at DGMC, provides a life-cycle cost (LCC) analysis for each ERO, and prioritizes any life-cycle cost-effective EROs based on their net present value (NPV), value index (VI), and savings to investment ratio (SIR or ROI). Analysis results are presented for 17 EROs that involve energy use in the areas of lighting, fan and pump motors, boiler operation, infiltration, electric load peak reduction and cogeneration, electric rate structures, and natural gas supply. Typical current energy consumption is approximately 22,900 MWh of electricity (78,300 MBtu), 87,600 kcf of natural gas (90,300 MBtu), and 8,300 gal of fuel oil (1,200 MBtu). A summary of the savings potential by energy-use category of all independent cost-effective EROs is shown in a table. This table includes the first cost, yearly energy consumption savings, and NPV for each energy-use category. The net dollar savings and NPV values as derived by the life-cycle cost analysis are based on the 1992 federal discount rate of 4.6%. The implementation of all EROs could result in a yearly electricity savings of more than 6,000 MWh or 26% of current yearly electricity consumption. More than 15 MW of billable load (total billed by the utility for a 12-month period) or more than 34% of current billed demand could also be saved. Corresponding natural gas savings would be 1,050 kcf (just over 1% of current consumption). Total yearly net energy cost savings for all options would be greater than $343,340. This value does not include any operations and maintenance (O&M) savings.

  17. David Grant Medical Center energy use baseline and integrated resource assessment

    Energy Technology Data Exchange (ETDEWEB)

    Richman, E.E.; Hoshide, R.K.; Dittmer, A.L.

    1993-04-01

    The US Air Mobility Command (AMC) has tasked Pacific Northwest Laboratory (PNL) with supporting the US Department of Energy (DOE) Federal Energy Management Program's (FEMP) mission to identify, evaluate, and assist in acquiring all cost-effective energy resource opportunities (EROs) at the David Grant Medical Center (DGMC). This report describes the methodology used to identify and evaluate the EROs at DGMC, provides a life-cycle cost (LCC) analysis for each ERO, and prioritizes any life-cycle cost-effective EROs based on their net present value (NPV), value index (VI), and savings to investment ratio (SIR or ROI). Analysis results are presented for 17 EROs that involve energy use in the areas of lighting, fan and pump motors, boiler operation, infiltration, electric load peak reduction and cogeneration, electric rate structures, and natural gas supply. Typical current energy consumption is approximately 22,900 MWh of electricity (78,300 MBtu), 87,600 kcf of natural gas (90,300 MBtu), and 8,300 gal of fuel oil (1,200 MBtu). A summary of the savings potential by energy-use category of all independent cost-effective EROs is shown in a table. This table includes the first cost, yearly energy consumption savings, and NPV for each energy-use category. The net dollar savings and NPV values as derived by the life-cycle cost analysis are based on the 1992 federal discount rate of 4.6%. The implementation of all EROs could result in a yearly electricity savings of more than 6,000 MWh or 26% of current yearly electricity consumption. More than 15 MW of billable load (total billed by the utility for a 12-month period) or more than 34% of current billed demand could also be saved. Corresponding natural gas savings would be 1,050 kcf (just over 1% of current consumption). Total yearly net energy cost savings for all options would be greater than $343,340. This value does not include any operations and maintenance (O M) savings.

  18. Characterization of the radiation environment at the UNLV accelerator facility during operation of the Varian M6 linac

    Science.gov (United States)

    Hodges, M.; Barzilov, A.; Chen, Y.; Lowe, D.

    2016-10-01

    The bremsstrahlung photon flux from the UNLV particle accelerator (Varian M6 model) was determined using MCNP5 code for 3 MeV and 6 MeV incident electrons. Human biological equivalent dose rates due to accelerator operation were evaluated using the photon flux with the flux-to-dose conversion factors. Dose rates were computed for the accelerator facility for M6 linac use under different operating conditions. The results showed that the use of collimators and linac internal shielding significantly reduced the dose rates throughout the facility. It was shown that the walls of the facility, in addition to the earthen berm enveloping the building, provide equivalent shielding to reduce dose rates outside to below the 2 mrem/h limit.

  19. SU-E-T-406: Use of TrueBeam Developer Mode and API to Increase the Efficiency and Accuracy of Commissioning Measurements for the Varian EDGE Stereotactic Linac

    International Nuclear Information System (INIS)

    Gardner, S; Gulam, M; Song, K; Li, H; Huang, Y; Zhao, B; Qin, Y; Snyder, K; Kim, J; Gordon, J; Chetty, I; Wen, N

    2014-01-01

    ). The scripting also allowed for creation of the files in advance without requiring access to TPS. The API scripting functionality enabled efficient creation/mining of TPS data. Finally, automation reduces the potential for human error in entering linac values at the machine console,and the script provides a log of measurements acquired for each session. This research was supported in part by a grant from Varian Medical Systems, Palo Alto, CA

  20. A Wireless Magnetic Resonance Energy Transfer System for Micro Implantable Medical Sensors

    Directory of Open Access Journals (Sweden)

    Tianyang Yang

    2012-07-01

    Full Text Available Based on the magnetic resonance coupling principle, in this paper a wireless energy transfer system is designed and implemented for the power supply of micro-implantable medical sensors. The entire system is composed of the in vitro part, including the energy transmitting circuit and resonant transmitter coils, and in vivo part, including the micro resonant receiver coils and signal shaping chip which includes the rectifier module and LDO voltage regulator module. Transmitter and receiver coils are wound by Litz wire, and the diameter of the receiver coils is just 1.9 cm. The energy transfer efficiency of the four-coil system is greatly improved compared to the conventional two-coil system. When the distance between the transmitter coils and the receiver coils is 1.5 cm, the transfer efficiency is 85% at the frequency of 742 kHz. The power transfer efficiency can be optimized by adding magnetic enhanced resonators. The receiving voltage signal is converted to a stable output voltage of 3.3 V and a current of 10 mA at the distance of 2 cm. In addition, the output current varies with changes in the distance. The whole implanted part is packaged with PDMS of excellent biocompatibility and the volume of it is about 1 cm3.

  1. Monte Carlo dose calculation improvements for low energy electron beams using eMC

    International Nuclear Information System (INIS)

    Fix, Michael K; Frei, Daniel; Volken, Werner; Born, Ernst J; Manser, Peter; Neuenschwander, Hans

    2010-01-01

    The electron Monte Carlo (eMC) dose calculation algorithm in Eclipse (Varian Medical Systems) is based on the macro MC method and is able to predict dose distributions for high energy electron beams with high accuracy. However, there are limitations for low energy electron beams. This work aims to improve the accuracy of the dose calculation using eMC for 4 and 6 MeV electron beams of Varian linear accelerators. Improvements implemented into the eMC include (1) improved determination of the initial electron energy spectrum by increased resolution of mono-energetic depth dose curves used during beam configuration; (2) inclusion of all the scrapers of the applicator in the beam model; (3) reduction of the maximum size of the sphere to be selected within the macro MC transport when the energy of the incident electron is below certain thresholds. The impact of these changes in eMC is investigated by comparing calculated dose distributions for 4 and 6 MeV electron beams at source to surface distance (SSD) of 100 and 110 cm with applicators ranging from 6 x 6 to 25 x 25 cm 2 of a Varian Clinac 2300C/D with the corresponding measurements. Dose differences between calculated and measured absolute depth dose curves are reduced from 6% to less than 1.5% for both energies and all applicators considered at SSD of 100 cm. Using the original eMC implementation, absolute dose profiles at depths of 1 cm, d max and R50 in water lead to dose differences of up to 8% for applicators larger than 15 x 15 cm 2 at SSD 100 cm. Those differences are now reduced to less than 2% for all dose profiles investigated when the improved version of eMC is used. At SSD of 110 cm the dose difference for the original eMC version is even more pronounced and can be larger than 10%. Those differences are reduced to within 2% or 2 mm with the improved version of eMC. In this work several enhancements were made in the eMC algorithm leading to significant improvements in the accuracy of the dose calculation

  2. Monte Carlo dose calculation improvements for low energy electron beams using eMC.

    Science.gov (United States)

    Fix, Michael K; Frei, Daniel; Volken, Werner; Neuenschwander, Hans; Born, Ernst J; Manser, Peter

    2010-08-21

    The electron Monte Carlo (eMC) dose calculation algorithm in Eclipse (Varian Medical Systems) is based on the macro MC method and is able to predict dose distributions for high energy electron beams with high accuracy. However, there are limitations for low energy electron beams. This work aims to improve the accuracy of the dose calculation using eMC for 4 and 6 MeV electron beams of Varian linear accelerators. Improvements implemented into the eMC include (1) improved determination of the initial electron energy spectrum by increased resolution of mono-energetic depth dose curves used during beam configuration; (2) inclusion of all the scrapers of the applicator in the beam model; (3) reduction of the maximum size of the sphere to be selected within the macro MC transport when the energy of the incident electron is below certain thresholds. The impact of these changes in eMC is investigated by comparing calculated dose distributions for 4 and 6 MeV electron beams at source to surface distance (SSD) of 100 and 110 cm with applicators ranging from 6 x 6 to 25 x 25 cm(2) of a Varian Clinac 2300C/D with the corresponding measurements. Dose differences between calculated and measured absolute depth dose curves are reduced from 6% to less than 1.5% for both energies and all applicators considered at SSD of 100 cm. Using the original eMC implementation, absolute dose profiles at depths of 1 cm, d(max) and R50 in water lead to dose differences of up to 8% for applicators larger than 15 x 15 cm(2) at SSD 100 cm. Those differences are now reduced to less than 2% for all dose profiles investigated when the improved version of eMC is used. At SSD of 110 cm the dose difference for the original eMC version is even more pronounced and can be larger than 10%. Those differences are reduced to within 2% or 2 mm with the improved version of eMC. In this work several enhancements were made in the eMC algorithm leading to significant improvements in the accuracy of the dose

  3. Safe bunker designing for the 18 MV Varian 2100 Clinac: a comparison between Monte Carlo simulation based upon data and new protocol recommendations.

    Science.gov (United States)

    Beigi, Manije; Afarande, Fatemeh; Ghiasi, Hosein

    2016-01-01

    The aim of this study was to compare two bunkers designed by only protocols recommendations and Monte Carlo (MC) based upon data derived for an 18 MV Varian 2100Clinac accelerator. High energy radiation therapy is associated with fast and thermal photoneutrons. Adequate shielding against the contaminant neutron has been recommended by IAEA and NCRP new protocols. The latest protocols released by the IAEA (safety report No. 47) and NCRP report No. 151 were used for the bunker designing calculations. MC method based upon data was also derived. Two bunkers using protocols and MC upon data were designed and discussed. From designed door's thickness, the door designed by the MC simulation and Wu-McGinley analytical method was closer in both BPE and lead thickness. In the case of the primary and secondary barriers, MC simulation resulted in 440.11 mm for the ordinary concrete, total concrete thickness of 1709 mm was required. Calculating the same parameters value with the recommended analytical methods resulted in 1762 mm for the required thickness using 445 mm as recommended by TVL for the concrete. Additionally, for the secondary barrier the thickness of 752.05 mm was obtained. Our results showed MC simulation and the followed protocols recommendations in dose calculation are in good agreement in the radiation contamination dose calculation. Difference between the two analytical and MC simulation methods revealed that the application of only one method for the bunker design may lead to underestimation or overestimation in dose and shielding calculations.

  4. Neutron dose to patients treated with high-energy medical accelerators

    International Nuclear Information System (INIS)

    McGinley, P.H.

    2001-01-01

    The neutron dose equivalent received by patients treated with high energy x-ray beams was measured in this research. A total of 13 different medical accelerators were evaluated in terms of the neutron dose equivalent in the patient plane and at the beam center. The neutron dose equivalent at the beam center was found to ranged from 0.02 to 9.4 mSv per Sv of x-ray dose and values from 0.029 to 2.58 mSv per Sv of x-ray were measured in the patient plane. It was concluded that the neutron levels meet the International Electrotechnical Commission standard for the patient plane. It was also concluded that when intensity modulated radiation treatment is conducted the neutron dose equivalent received by the patient will increase by a factor of 2 to 10. (author)

  5. Female sex pheromone and male behavioral responses of the bombycid moth Trilocha varians: comparison with those of the domesticated silkmoth Bombyx mori

    Science.gov (United States)

    Daimon, Takaaki; Fujii, Takeshi; Yago, Masaya; Hsu, Yu-Feng; Nakajima, Yumiko; Fujii, Tsuguru; Katsuma, Susumu; Ishikawa, Yukio; Shimada, Toru

    2012-03-01

    Analysis of female sex pheromone components and subsequent field trap experiments demonstrated that the bombycid moth Trilocha varians uses a mixture of ( E, Z)-10,12-hexadecadienal (bombykal) and ( E,Z)-10,12-hexadecadienyl acetate (bombykyl acetate) as a sex pheromone. Both of these components are derivatives of ( E,Z)-10,12-hexadecadienol (bombykol), the sex pheromone of the domesticated silkmoth Bombyx mori. This finding prompted us to compare the antennal and behavioral responses of T. varians and B. mori to bombykol, bombykal, and bombykyl acetate in detail. The antennae of T. varians males responded to bombykal and bombykyl acetate but not to bombykol, and males were attracted only when lures contained both bombykal and bombykyl acetate. In contrast, the antennae of B. mori males responded to all the three components. Behavioral analysis showed that B. mori males responded to neither bombykal nor bombykyl acetate. Meanwhile, the wing fluttering response of B. mori males to bombykol was strongly inhibited by bombykal and bombykyl acetate, thereby indicating that bombykal and bombykyl acetate act as behavioral antagonists for B. mori males. T. varians would serve as a reference species for B. mori in future investigations into the molecular mechanisms underlying the evolution of sex pheromone communication systems in bombycid moths.

  6. Localized Energy-Based Normalization of Medical Images: Application to Chest Radiography.

    Science.gov (United States)

    Philipsen, R H H M; Maduskar, P; Hogeweg, L; Melendez, J; Sánchez, C I; van Ginneken, B

    2015-09-01

    Automated quantitative analysis systems for medical images often lack the capability to successfully process images from multiple sources. Normalization of such images prior to further analysis is a possible solution to this limitation. This work presents a general method to normalize medical images and thoroughly investigates its effectiveness for chest radiography (CXR). The method starts with an energy decomposition of the image in different bands. Next, each band's localized energy is scaled to a reference value and the image is reconstructed. We investigate iterative and local application of this technique. The normalization is applied iteratively to the lung fields on six datasets from different sources, each comprising 50 normal CXRs and 50 abnormal CXRs. The method is evaluated in three supervised computer-aided detection tasks related to CXR analysis and compared to two reference normalization methods. In the first task, automatic lung segmentation, the average Jaccard overlap significantly increased from 0.72±0.30 and 0.87±0.11 for both reference methods to with normalization. The second experiment was aimed at segmentation of the clavicles. The reference methods had an average Jaccard index of 0.57±0.26 and 0.53±0.26; with normalization this significantly increased to . The third experiment was detection of tuberculosis related abnormalities in the lung fields. The average area under the Receiver Operating Curve increased significantly from 0.72±0.14 and 0.79±0.06 using the reference methods to with normalization. We conclude that the normalization can be successfully applied in chest radiography and makes supervised systems more generally applicable to data from different sources.

  7. The neutron dose equivalent around high energy medical electron linear accelerators

    Directory of Open Access Journals (Sweden)

    Poje Marina

    2014-01-01

    Full Text Available The measurement of neutron dose equivalent was made in four dual energy linear accelerator rooms. Two of the rooms were reconstructed after decommissioning of 60Co units, so the main limitation was the space. The measurements were performed by a nuclear track etched detectors LR-115 associated with the converter (radiator that consist of 10B and with the active neutron detector Thermo BIOREM FHT 742. The detectors were set at several locations to evaluate the neutron ambient dose equivalent and/or neutron dose rate to which medical personnel could be exposed. Also, the neutron dose dependence on collimator aperture was analyzed. The obtained neutron dose rates outside the accelerator rooms were several times smaller than the neutron dose rates inside the accelerator rooms. Nevertheless, the measured neutron dose equivalent was not negligible from the aspect of the personal dosimetry with almost 2 mSv a year per person in the areas occupied by staff (conservative estimation. In rooms with 15 MV accelerators, the neutron exposure to the personnel was significantly lower than in the rooms having 18 MV accelerators installed. It was even more pronounced in the room reconstructed after the 60Co decommissioning. This study confirms that shielding from the neutron radiation should be considered when building vaults for high energy linear accelerators, especially when the space constraints exist.

  8. Surface dose characterisation of the Varian Ir-192 HDR conical surface applicator set with a vertically orientated source

    Energy Technology Data Exchange (ETDEWEB)

    Buchauer, Konrad; Henke, Guido; Schiefer, Hans; Plasswilm, Ludwig [Kantonsspital St. Gallen, Department of Radiation Oncology, St. Gallen (Switzerland)

    2014-12-15

    Conical surface applicators with an Ir-192 high-dose-rate brachytherapy source are a common modality for the treatment of non-melanomatous skin cancer with high tumour control rates. Surface dose characterisation of the Varian Varisource GammaMed+ IX afterloader vertical type surface applicators is performed two dimensionally using high-resolution film dosimetry. The focus of this study was to determine if Varian surface applicators with a vertical source suffer from the dose distribution irregularities reported for comparable applicators. Our goal was to evaluate if the irregularities found affected treatment and dose output verification procedures. Ionisation chamber-based verification of applicator output was established according to guidelines provided by the manufacturer. For additional measurement of surface dose Gafchromic EBT3 film dosimetry was used. The term ''therapeutic dose'' was defined as 85 % of the prescribed dose level. For the 10 different applicator inserts evaluated, cold spots were observed. Mean cold spot size was 2.0 mm x 3.6 mm (± 0.6 mm). The cold spots were dosimetrically well below 85 % of the prescribed dose. The cold spot was situated 2.2 mm (1.4-2.7 mm) unilaterally from the central axis and caused general asymmetry in the dose profiles intersecting the cold spot area. A source tilt of approximately 8 (± 1 ) was determined for the source used for irradiation. A central underdosed area exceeding 15 % of the prescribed dose has not been previously reported. Source tilt was observed and found to affect clinical use and possibly treatment outcome in applicators using a vertically arranged source. Surface applicators with a vertically orientated source were subject to dose irregularities that could impact on chamber-based applicator output verification procedures. We recommend film dosimetry-backed applicator commissioning to avoid systematic errors. (orig.) [German] Konische Oberflaechenapplikatoren sind ein

  9. Prevalence and Side Effects of Energy Drink Consumption among Medical Students at Umm Al-Qura University, Saudi Arabia

    Directory of Open Access Journals (Sweden)

    Naif A. Bawazeer

    2013-12-01

    Full Text Available Background: Energy drinks are freely available at markets and shops on the university campus without regulation or proper education regarding its side effects. The caffeine amount within energy drinks is high and could become an addictive substance or cause intoxication. Therefore, this study aims to assess the prevalence of energy drink consumption and its reported side effects among medical students. Methods:A total number of 257 medical students from Umm Al-Qura University completed a questionnaire about energy drinks that was administrated electronically from September through November, 2012. Results:Out of the 257 participants, 27.2% (n=70 reported consuming at least one energy drink per month, with 61.5% (n=48 being males. Males consume significantly more energy drinks than females (p=0.0001. The students consumed energy drinks to get energy in general (32.8% and while studying for exams or finishing a project (31.4%. Other reasons given include, lack of sleep (12.8%, just to be like friends (11.4%, or driving (8.5%. Heart palpitations are the most common side effect in our sample (20%, followed by insomnia (10%, headache and tremors (5.7%, nausea and vomiting (4.2% and nervousness (2.8%. Conclusion: Energy drinks consumption is common practice among medical students and the main reason cited for consumption is the need for energy during general activities. Approximately one-third of the consumers manifested some side effect after consumption. We recommend the need to create public awareness about energy drinks. Further studies are recommended to assess the educational level of students consuming energy drinks, about the dangerous side effects.

  10. Monte Carlo simulation of a varian 21EX Clinac 6 MV photon beam characteristics using GATE6

    Energy Technology Data Exchange (ETDEWEB)

    An, Jung Su [Korea Atomic Energy Research Institute, Nonproliferation System Research Division, Daejeon (Korea, Republic of); Lee, Chang Lae [Center for Radiological Environment and Health Science, Busan (Korea, Republic of); Baek, Cheol Ha [Dept. of Radiological Science, College of Health Science, Yonsei University, Seoul (Korea, Republic of)

    2016-12-15

    Monte Carlo simulations are widely used as the most accurate technique for dose calculation in radiation therapy. In this paper, the GATE6(Geant4 Application for Tomographic Emission ver.6) code was employed to calculate the dosimetric performance of the photon beams from a linear accelerator(LINAC). The treatment head of a Varian 21EX Clinac was modeled including the major geometric structures within the beam path such as a target, a primary collimator, a flattening filter, a ion chamber, and jaws. The 6 MV photon spectra were characterized in a standard 10 x 10 cm{sup 2} field at 100 cm source-to-surface distance(SSD) and subsequent dose estimations were made in a water phantom. The measurements of percentage depth dose and dose profiles were performed with 3D water phantom and the simulated data was compared to measured reference data. The simulated results agreed very well with the measured data. It has been found that the GATE6 code is an effective tool for dose optimization in radiotherapy applications.

  11. Energy expenditure estimation in beta-blocker-medicated cardiac patients by combining heart rate and body movement data

    NARCIS (Netherlands)

    Kraal, Jos J.; Sartor, Francesco; Papini, Gabriele; Stut, Wim; Peek, Niels; Kemps, Hareld Mc; Bonomi, Alberto G.

    2016-01-01

    Accurate assessment of energy expenditure provides an opportunity to monitor physical activity during cardiac rehabilitation. However, the available assessment methods, based on the combination of heart rate (HR) and body movement data, are not applicable for patients using beta-blocker medication.

  12. 76 FR 19174 - In the Matter of Circuit Systems, Inc., Global Energy Group, Inc., Integrated Medical Resources...

    Science.gov (United States)

    2011-04-06

    ... SECURITIES AND EXCHANGE COMMISSION File No. 500-1 In the Matter of Circuit Systems, Inc., Global Energy Group, Inc., Integrated Medical Resources, Inc., iNTELEFILM Corp., and Lot$off Corp.; Order of... lack of current and accurate information concerning the securities of Circuit Systems, Inc. because it...

  13. A dual-energy medical instrument for measurement of x-ray source voltage and dose rate

    Science.gov (United States)

    Ryzhikov, V. D.; Naydenov, S. V.; Volkov, V. G.; Opolonin, O. D.; Makhota, S.; Pochet, T.; Smith, C. F.

    2016-03-01

    An original dual-energy detector and medical instrument have been developed to measure the output voltages and dose rates of X-ray sources. Theoretical and experimental studies were carried out to characterize the parameters of a new scintillator-photodiode sandwich-detector based on specially-prepared zinc selenide crystals in which the low-energy detector (LED) works both as the detector of the low-energy radiation and as an absorption filter allowing the highenergy fraction of the radiation to pass through to the high-energy detector (HED). The use of the LED as a low-energy filter in combination with a separate HED opens broad possibilities for such sandwich structures. In particular, it becomes possible to analyze and process the sum, difference and ratio of signals coming from these detectors, ensuring a broad (up to 106) measurement range of X-ray intensity from the source and a leveling of the energy dependence. We have chosen an optimum design of the detector and the geometry of the component LED and HED parts that allow energy-dependence leveling to within specified limits. The deviation in energy dependence of the detector does not exceed about 5% in the energy range from 30 to 120 keV. The developed detector and instrument allow contactless measurement of the anode voltage of an X-ray emitter from 40 to 140 kV with an error no greater than 3%. The dose rate measurement range is from 1 to 200 R/min. An original medical instrument has passed clinical testing and was recommended for use in medical institutions for X-ray diagnostics.

  14. Orthogonal image pairs coupled with OSMS for noncoplanar beam angle, intracranial, single-isocenter, SRS treatments with multiple targets on the Varian Edge radiosurgery system

    Directory of Open Access Journals (Sweden)

    Jasmine A. Oliver, PhD

    2017-07-01

    Conclusion: Based on our study, CR-induced shifts with the Varian Edge radiosurgery system will not produce noticeable dosimetric effects for SRS treatments. Thus, replacing cone beam CT with orthogonal kV/kV pairs coupled with OSMS at the treatment couch angle could reduce the number of cone beam CT scans that are acquired during a standard SRS treatment while providing an accurate and safe treatment with negligible dosimetric effects on the treatment plan.

  15. Modelling of a linear accelerator VARIAN 600 C/D for dosimetric study using the Monte Carlo Method; Modelamento de um acelerador linear VARIAN 600 C/D para estudo dosimétrico usando o Método de Monte Carlo

    Energy Technology Data Exchange (ETDEWEB)

    Cancino, Jorge Luis Batista

    2016-07-01

    Based on the high availability of low energy linear accelerators in Brazil and with the goal of developing a reliable tool for dose distribution calculations in radiotherapy; this research aims to validate a linear accelerator head model using MCNP Monte Carlo code. The Varian 600 C/D linear accelerator installed at the Hospital São João de is taken as reference. The main components of the linear accelerator head were simulated based on detailed information of the manufacturer. In order to calculate dose distribution, a water phantom with dimensions of 30 x 30 x 30 cm{sup 3} was simulated and placed at 100 cm of source-surface distance. A monoenergetic electron beam of 6,3 MeV was considered as a source. The number of primary particles used in the simulation was 10{sup 8}. A Phase-Space Surface was used to scoring the photon spectrum below the tungsten target. Others two were placed in the model in order to reduce computational time and improve statistical accuracy. In order to validate the developed model, the X-ray spectrum generated by Bremsstrahlung was calculated and analyzed. Furthermore, the results of percentage depth doses and beam profiles calculations were compared with available measurements. The MCNP calculations results were compared to measurement showing good agreement between them. The comparison between MCNP calculations and measurement of PDD showed reasonable coherence at build-up region. The results were in an acceptable interval of confidence at the flat region of beam profiles comparison for three different field sizes. In this work, we compared MCNP calculations to experimental data in order to validate the developed LINAC head model. The results showed a good agreement according to the recommended criteria. The developed model was validated as an accurate tool for LINAC quality control procedures. (author)

  16. SU-F-T-526: A Comparative Study On Gating Efficiency of Varian RPM Device and Calypso System

    Energy Technology Data Exchange (ETDEWEB)

    Ravindran, P [Christian Medical College Hospital, Vellore (India); Wui Ann, W; Lim, Y [The Brunei Cancer Center (Brunei Darussalam)

    2016-06-15

    Purpose: In general, the linear accelerator is gated using respiratory signal obtained by way of external sensors to account for the breathing motion during radiotherapy. One of the commonly used gating devices is the Varian RPM device. Calypso system that uses electromagnetic tracking of implanted or surface transponders could also be used for gating. The aim of this study is to compare the gating efficiency of RPM device and the calypso system by phantom studies. Methods: An ArcCheck insert was used as the phantom with a Gafchromic film placed in its holder. The ArcCheck insert was placed on a Motion Sim platform and moved in the longitudinal direction simulating a respiratory motion with a period of 5 seconds and amplitude of ±6mm. The Gafchromic film was exposed to a 2 × 2cm{sup 2} field, i) with the phantom static, ii) phantom moving but ungated iii) gated with gating window of 2mm and 3mm. This was repeated with Calypso system using surface transponders with the same gating window. The Gafchromic films were read with an EPSON 11000 flatbed scanner and analysed with ‘Medphysto’ software. Results: The full width at half maximum (FWHM) as measured with film at the level of the film holder was 1.65cm when the phantom was static. FWHM measured with phantom moving and without gating was 1.16 cm and penumbra was 7 mm (80–20%) on both sides. When the beam was gated with 2 mm gating window the FWHM was 1.8 cm with RPM device and 1.9 cm with Calypso. Similarly, when the beam was gated with 3 mm window, the FWHM was 1.9cm with RPM device and 2cm with Calypso. Conclusion: This work suggests that the gating efficiency of RPM device is better than that of the Calypso with surface transponder, with reference to the latency in gating.

  17. Industrial and medical applications of accelerators with energies less than 20 MeV

    International Nuclear Information System (INIS)

    Duggan, J.L.

    1983-01-01

    In this paper the medical and industrial application of small accelerators is reviewed. Most of the material is taken from the Seventh Conference on the Application of Accelerators in Research and Industry, which was held in Denton, Texas in November of 1982. The areas covered include medical linacs, cyclotron design and production of medical radioisotopes, radiation processing, ion implantation for the metallurgical and semiconductor industries, oil and mineral exploration, trace, surface and bulk analysis, and unique accelerators for all of the above applications

  18. U.S. Department of Energy Office of Occupational Medicine and Medical Surveillance 1995--1997 triannual report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-08-01

    From 1995 through 1997 the Office of Occupational Medicine and Medical Surveillance (EH-61) has made numerous achievements that have enhanced the performance of the office and more importantly, the Department of Energy (DOE). This report provides specific information about program activities and accomplishments, as well as individual contacts for each program. The mission of EH-61 is the prevention of worker illness by fostering outstanding occupational medicine and medical surveillance programs within the DOE complex. This mission is being realized as a result of efforts in four main business lines: (1) Surveillance; (2) Research, (3) Policy/Technical Support; and (4) Information/Communication.

  19. Increased physical activity not decreased energy intake is associated with inpatient medical treatment for anorexia nervosa in adolescent females.

    Directory of Open Access Journals (Sweden)

    Janine Higgins

    Full Text Available There is a dearth of data regarding changes in dietary intake and physical activity over time that lead to inpatient medical treatment for anorexia nervosa (AN. Without such data, more effective nutritional therapies for patients cannot be devised. This study was undertaken to describe changes in diet and physical activity that precede inpatient medical hospitalization for AN in female adolescents. This data can be used to understand factors contributing to medical instability in AN, and may advance rodent models of AN to investigate novel weight restoration strategies. It was hypothesized that hospitalization for AN would be associated with progressive energy restriction and increased physical activity over time. 20 females, 11-19 years (14.3±1.8 years, with restricting type AN, completed retrospective, self-report questionnaires to assess dietary intake and physical activity over the 6 month period prior to inpatient admission (food frequency questionnaire, Pediatric physical activity recall and 1 week prior (24 hour food recall, modifiable activity questionnaire. Physical activity increased acutely prior to inpatient admission without any change in energy or macronutrient intake. However, there were significant changes in reported micronutrient intake causing inadequate intake of Vitamin A, Vitamin D, and pantothenic acid at 1 week versus high, potentially harmful, intake of Vitamin A over 6 months prior to admission. Subject report of significantly increased physical activity, not decreased energy intake, were associated with medical hospitalization for AN. Physical activity and Vitamin A and D intake should be carefully monitored following initial AN diagnosis, as markers of disease progression as to potentially minimize the risk of medical instability.

  20. Validation of Varian TrueBeam electron phase–spaces for Monte Carlo simulation of MLC-shaped fields

    International Nuclear Information System (INIS)

    Lloyd, Samantha A. M.; Gagne, Isabelle M.; Zavgorodni, Sergei; Bazalova-Carter, Magdalena

    2016-01-01

    Purpose: This work evaluates Varian’s electron phase–space sources for Monte Carlo simulation of the TrueBeam for modulated electron radiation therapy (MERT) and combined, modulated photon and electron radiation therapy (MPERT) where fields are shaped by the photon multileaf collimator (MLC) and delivered at 70 cm SSD. Methods: Monte Carlo simulations performed with EGSnrc-based BEAMnrc/DOSXYZnrc and PENELOPE-based PRIMO are compared against diode measurements for 5 × 5, 10 × 10, and 20 × 20 cm 2 MLC-shaped fields delivered with 6, 12, and 20 MeV electrons at 70 cm SSD (jaws set to 40 × 40 cm 2 ). Depth dose curves and profiles are examined. In addition, EGSnrc-based simulations of relative output as a function of MLC-field size and jaw-position are compared against ion chamber measurements for MLC-shaped fields between 3 × 3 and 25 × 25 cm 2 and jaw positions that range from the MLC-field size to 40 × 40 cm 2 . Results: Percent depth dose curves generated by BEAMnrc/DOSXYZnrc and PRIMO agree with measurement within 2%, 2 mm except for PRIMO’s 12 MeV, 20 × 20 cm 2 field where 90% of dose points agree within 2%, 2 mm. Without the distance to agreement, differences between measurement and simulation are as large as 7.3%. Characterization of simulated dose parameters such as FWHM, penumbra width and depths of 90%, 80%, 50%, and 20% dose agree within 2 mm of measurement for all fields except for the FWHM of the 6 MeV, 20 × 20 cm 2 field which falls within 2 mm distance to agreement. Differences between simulation and measurement exist in the profile shoulders and penumbra tails, in particular for 10 × 10 and 20 × 20 cm 2 fields of 20 MeV electrons, where both sets of simulated data fall short of measurement by as much as 3.5%. BEAMnrc/DOSXYZnrc simulated outputs agree with measurement within 2.3% except for 6 MeV MLC-shaped fields. Discrepancies here are as great as 5.5%. Conclusions: TrueBeam electron phase–spaces available from Varian have been

  1. Validation of Varian TrueBeam electron phase–spaces for Monte Carlo simulation of MLC-shaped fields

    Energy Technology Data Exchange (ETDEWEB)

    Lloyd, Samantha A. M. [Department of Physics and Astronomy, University of Victoria, Victoria, British Columbia V8P 3P6 5C2 (Canada); Gagne, Isabelle M., E-mail: imgagne@bccancer.bc.ca; Zavgorodni, Sergei [Department of Medical Physics, BC Cancer Agency–Vancouver Island Centre, Victoria, British Columbia V8R 6V5, Canada and Department of Physics and Astronomy, University of Victoria, Victoria, British Columbia V8W 3P6 5C2 (Canada); Bazalova-Carter, Magdalena [Department of Physics and Astronomy, University of Victoria, Victoria, British Columbia V8W 3P6 5C2 (Canada)

    2016-06-15

    spaces available from Varian have been implemented in two distinct Monte Carlo simulation packages to produce dose distributions and outputs that largely reflect measurement. Differences exist in the profile shoulders and penumbra tails for the 20 MeV phase–space off-axis and in the outputs for the 6 MeV phase–space.

  2. Evaluation using Monte Carlo simulations, of the effect of a shielding, called external shielding, for fotoneutrons generated in linear accelerators, using the computational model of Varian accelerator 2300 C/D operating in eight rotation angles of the GA

    International Nuclear Information System (INIS)

    Silva, Hugo R.; Silva, Ademir X.; Rebello, Wilson F.; Silva, Maria G.

    2011-01-01

    This paper aims to present the results obtained by Monte Carlo simulation of the effect of shielding against neutrons, called External Shielding, to be placed on the heads of linear accelerators used in radiotherapy. For this, it was used the radiation transport code Monte Carlo N-Particle - MCNPX, in which were developed computational model of the head of the linear accelerator Varian 2300 C/D. The equipment was simulated within a bunker, operating at energies of 10, 15 and 18 MV, considering the rotation of the gantry at eight different angles ( 0 deg, 45 deg, 90 deg, 135 deg, 180 deg, 225 deg, 270 deg and 315 deg), in all cases, the equipment was modeled without and with the shielding positioned attached to the head of the accelerator on its bottom. In each of these settings, it was calculated the Ambient Dose Equivalent due to neutron H * (10)n on points situated in the region of the patient (region of interest for evaluation of undesirable neutron doses on the patient) and in the maze of radiotherapy room (region of interest for shielding the access door to the bunker). It was observed for all energies of equipment operation as well as for all angles of inclination of the gantry, a significant reduction in the values of H * (10) n when the equipment operated with the external shielding, both in the region of the patient as in the region of the maze. (author)

  3. Life sciences: Nuclear medicine, radiation biology, medical physics, 1980-1994. International Atomic Energy Agency Publications

    International Nuclear Information System (INIS)

    1994-11-01

    The catalogue lists all sales publications of the IAEA dealing with Life Sciences issued during the period 1980-1994. The publications are grouped in the following chapters: Nuclear Medicine (including Radiopharmaceuticals), Radiation Biology and Medical Physics (including Dosimetry)

  4. Evaluation of latent variances in Monte Carlo dose calculations with Varian TrueBeam photon phase-spaces used as a particle source

    Science.gov (United States)

    Alhakeem, Eyad; Zavgorodni, Sergei

    2018-01-01

    The purpose of this study was to evaluate the latent variance (LV) of Varian TrueBeam photon phase-space files (PSF) for open 10  ×  10 cm2 and small stereotactic fields and estimate the number of phase spaces required to be summed up in order to maintain sub-percent LV in Monte Carlo (MC) dose calculations. BEAMnrc/DOSXYZnrc software was used to transport particles from Varian phase-space files (PSFA) through the secondary collimators. Transported particles were scored into another phase-space located under the jaws (PSFB), or transported further through the cone collimators and scored straight below, forming PSFC. Phase-space files (PSFB) were scored for 6 MV-FFF, 6 MV, 10 MV-FFF, 10 MV and 15 MV beams with 10  ×  10 cm2 field size, and PSFC were scored for 6 MV beam under circular cones of 0.13, 0.25, 0.35, and 1 cm diameter. Both PSFB and PSFC were transported into a water phantom with particle recycling number ranging from 10 to 1000. For 10  ×  10 cm2 fields 0.5  ×  0.5  ×  0.5 cm3 voxels were used to score the dose, whereas the dose was scored in 0.1  ×  0.1  ×  0.5 cm3 voxels for beams collimated with small cones. In addition, for small 0.25 cm diameter cone-collimated 6 MV beam, phantom voxel size varied as 0.02  ×  0.02  ×  0.5 cm3, 0.05  ×  0.05  ×  0.5 cm3 and 0.1  ×  0.1  ×  0.5 cm3. Dose variances were scored in all cases and LV evaluated as per Sempau et al. For the 10  ×  10 cm2 fields calculated LVs were greatest at the phantom surface and decreased with depth until they reached a plateau at 5 cm depth. LVs were found to be 0.54%, 0.96%, 0.35%, 0.69% and 0.57% for the 6 MV-FFF, 6 MV, 10 MV-FFF, 10 MV and 15 MV energies, respectively at the depth of 10 cm. For the 6 MV phase-space collimated with cones of 0.13, 0.25, 0.35, 1.0 cm diameter, the LVs calculated at 1.5 cm depth were 75.6%, 25.4%, 17

  5. Energy expenditure estimation in beta-blocker-medicated cardiac patients by combining heart rate and body movement data.

    Science.gov (United States)

    Kraal, Jos J; Sartor, Francesco; Papini, Gabriele; Stut, Wim; Peek, Niels; Kemps, Hareld Mc; Bonomi, Alberto G

    2016-11-01

    Accurate assessment of energy expenditure provides an opportunity to monitor physical activity during cardiac rehabilitation. However, the available assessment methods, based on the combination of heart rate (HR) and body movement data, are not applicable for patients using beta-blocker medication. Therefore, we developed an energy expenditure prediction model for beta-blocker-medicated cardiac rehabilitation patients. Sixteen male cardiac rehabilitation patients (age: 55.8 ± 7.3 years, weight: 93.1 ± 11.8 kg) underwent a physical activity protocol with 11 low- to moderate-intensity common daily life activities. Energy expenditure was assessed using a portable indirect calorimeter. HR and body movement data were recorded during the protocol using unobtrusive wearable devices. In addition, patients underwent a symptom-limited exercise test and resting metabolic rate assessment. Energy expenditure estimation models were developed using multivariate regression analyses based on HR and body movement data and/or patient characteristics. In addition, a HR-flex model was developed. The model combining HR and body movement data and patient characteristics showed the highest correlation and lowest error (r 2  = 0.84, root mean squared error = 0.834 kcal/minute) with total energy expenditure. The method based on individual calibration data (HR-flex) showed lower accuracy (i 2  = 0.83, root mean squared error = 0.992 kcal/minute). Our results show that combining HR and body movement data improves the accuracy of energy expenditure prediction models in cardiac patients, similar to methods that have been developed for healthy subjects. The proposed methodology does not require individual calibration and is based on the data that are available in clinical practice. © The European Society of Cardiology 2016.

  6. SU-E-T-325: The New Evaluation Method of the VMAT Plan Delivery Using Varian DynaLog Files and Modulation Complexity Score (MCS)

    Energy Technology Data Exchange (ETDEWEB)

    Tateoka, K [Proton Treatment Center, Radiation Therapy Research Institute, Social Medical Corporation Teishinkai, Sapporo (Japan); Graduate School of Medicine, Sapporo Medical University, Sapporo, JP (Japan); Fujimomo, K; Hareyama, M [Proton Treatment Center, Radiation Therapy Research Institute, Social Medical Corporation Teishinkai, Sapporo (Japan); Saitou, Y; Nakazawa, T; Abe, T; Nakata, A; Yano, M [Graduate School of Medicine, Sapporo Medical University, Sapporo, JP (Japan)

    2014-06-01

    Purpose: The aim of the study is to evaluate the use of Varian DynaLog files to verify VMAT plans delivery and modulation complexity score (MCS) of VMAT. Methods: Delivery accuracy of machine performance was quantified by multileaf collimator (MLC) position errors, gantry angle errors and fluence delivery accuracy for volumetric modulated arc therapy (VMAT). The relationship between machine performance and plan complexity were also investigated using the modulation complexity score (MCS). Plan and Actual MLC positions, gantry angles and delivered fraction of monitor units were extracted from Varian DynaLog files. These factors were taken from the record and verify system of MLC control file. Planned and delivered beam data were compared to determine leaf position errors and gantry angle errors. Analysis was also performed on planned and actual fluence maps reconstructed from those of the DynaLog files. This analysis was performed for all treatment fractions of 5 prostate VMAT plans. The analysis of DynaLog files have been carried out by in-house programming in Visual C++. Results: The root mean square of leaf position and gantry angle errors were about 0.12 and 0.15, respectively. The Gamma of planned and actual fluence maps at 3%/3 mm criterion was about 99.21. The gamma of the leaf position errors were not directly related to plan complexity as determined by the MCS. Therefore, the gamma of the gantry angle errors were directly related to plan complexity as determined by the MCS. Conclusion: This study shows Varian dynalog files for VMAT plan can be diagnosed delivery errors not possible with phantom based quality assurance. Furthermore, the MCS of VMAT plan can evaluate delivery accuracy for patients receiving of VMAT. Machine performance was found to be directly related to plan complexity but this is not the dominant determinant of delivery accuracy.

  7. The implications of temperature-mediated plasticity in larval instar number for development within a marine invertebrate, the shrimp Palaemonetes varians.

    Directory of Open Access Journals (Sweden)

    Andrew Oliphant

    Full Text Available Variations in larval instar number are common among arthropods. Here, we assess the implications of temperature-mediated variations in larval instar number for larval development time, larval growth rates, and juvenile dry weight within the palaemonid shrimp, Palaemonetes varians. In contrast with previous literature, which focuses on terrestrial arthropods, particularly model and pest species often of laboratory lines, we use wild shrimp, which differ in their life history from previous models. Newly-hatched P. varians larvae were first reared at 5, 10, 17, 25, and 30 °C to assess their thermal scope for development. Larvae developed at 17, 25, and 30 °C. At higher temperatures, larvae developed through fewer larval instars. Two dominant developmental pathways were observed; a short pathway of four instars and a long pathway of five instars. Longer developmental pathways of six to seven instars were rarely observed (mostly at lower temperatures and consisted of additional instars as 'repeat' instars; i.e. little developmental advance over the preceding instar. To assess the implications of temperature-mediated variation in larval instar number, newly-hatched larvae were then reared at 15, 20, and 25 °C. Again, the proportion of larvae developing through four instars increased with temperature. At all temperatures, larval development time and juvenile dry weight were greater for larvae developing through five instars. Importantly, because of the increasing proportion of larvae developing through four instars with increasing temperature, larval traits associated with this pathway (reduced development time and juvenile dry weight became more dominant. As a consequence of increasing growth rate with temperature, and the shift in the proportion of larvae developing through four instars, juvenile dry weight was greatest at intermediate temperatures (20 °C. We conclude that at settlement P. varians juveniles do not follow the temperature-size rule

  8. The implications of temperature-mediated plasticity in larval instar number for development within a marine invertebrate, the shrimp Palaemonetes varians.

    Science.gov (United States)

    Oliphant, Andrew; Hauton, Chris; Thatje, Sven

    2013-01-01

    Variations in larval instar number are common among arthropods. Here, we assess the implications of temperature-mediated variations in larval instar number for larval development time, larval growth rates, and juvenile dry weight within the palaemonid shrimp, Palaemonetes varians. In contrast with previous literature, which focuses on terrestrial arthropods, particularly model and pest species often of laboratory lines, we use wild shrimp, which differ in their life history from previous models. Newly-hatched P. varians larvae were first reared at 5, 10, 17, 25, and 30 °C to assess their thermal scope for development. Larvae developed at 17, 25, and 30 °C. At higher temperatures, larvae developed through fewer larval instars. Two dominant developmental pathways were observed; a short pathway of four instars and a long pathway of five instars. Longer developmental pathways of six to seven instars were rarely observed (mostly at lower temperatures) and consisted of additional instars as 'repeat' instars; i.e. little developmental advance over the preceding instar. To assess the implications of temperature-mediated variation in larval instar number, newly-hatched larvae were then reared at 15, 20, and 25 °C. Again, the proportion of larvae developing through four instars increased with temperature. At all temperatures, larval development time and juvenile dry weight were greater for larvae developing through five instars. Importantly, because of the increasing proportion of larvae developing through four instars with increasing temperature, larval traits associated with this pathway (reduced development time and juvenile dry weight) became more dominant. As a consequence of increasing growth rate with temperature, and the shift in the proportion of larvae developing through four instars, juvenile dry weight was greatest at intermediate temperatures (20 °C). We conclude that at settlement P. varians juveniles do not follow the temperature-size rule; this is of

  9. Spectral and dual-energy X-ray imaging for medical applications

    Science.gov (United States)

    Fredenberg, Erik

    2018-01-01

    Spectral imaging is an umbrella term for energy-resolved X-ray imaging in medicine. The technique makes use of the energy dependence of X-ray attenuation to either increase the contrast-to-noise ratio, or to provide quantitative image data and reduce image artefacts by so-called material decomposition. Spectral imaging is not new, but has gained interest in recent years because of rapidly increasing availability of spectral and dual-energy CT and the dawn of energy-resolved photon-counting detectors. This review examines the current technological status of spectral and dual-energy imaging and a number of practical applications of the technology in medicine.

  10. Electron linac for medical isotope production with improved energy efficiency and isotope recovery

    Science.gov (United States)

    Noonan, John; Walters, Dean; Virgo, Matt; Lewellen, John

    2015-09-08

    A method and isotope linac system are provided for producing radio-isotopes and for recovering isotopes. The isotope linac is an energy recovery linac (ERL) with an electron beam being transmitted through an isotope-producing target. The electron beam energy is recollected and re-injected into an accelerating structure. The ERL provides improved efficiency with reduced power requirements and provides improved thermal management of an isotope target and an electron-to-x-ray converter.

  11. FINAL REPORT FORMER RADIATION WORKER MEDICAL SURVEILLANCE PROGRAM AT ROCKY FLATS For Department of Energy Programs

    Energy Technology Data Exchange (ETDEWEB)

    Joe M. Aldrich

    2004-11-01

    The Former Radiation Worker Medical Surveillance Program at Rocky Flats was conducted in Arvada, CO, by Oak Ridge Associated Universities through the Oak Ridge Institute for Science and Education under DOE Contract DE-AC05-00OR22750. Objectives of the program were to obtain information on the value of medical surveillance among at-risk former radiation workers and to provide long-term internal radiation dosimetry information to the scientific community. This program provided the former radiation workers of the Rocky Flats Environmental Technology Site (formerly Rocky Flats Plant) an opportunity to receive follow-up medical monitoring and a re-evaluation of their internal radiation dose. The former Rocky Flats radiation worker population is distinctive because it was a reasonably stable work force that received occupational exposures, at times substantial, over several decades. This report reflects the summation of health outcomes, statistical analyses, and dose assessment information on former Rocky Flats radiation workers to the date of study termination as of March 2004.

  12. FINAL REPORT. FORMER RADIATION WORKER MEDICAL SURVEILLANCE PROGRAM AT ROCKY FLATS For Department of Energy Programs

    International Nuclear Information System (INIS)

    Aldrich, Joe M.

    2004-01-01

    The Former Radiation Worker Medical Surveillance Program at Rocky Flats was conducted in Arvada, CO, by Oak Ridge Associated Universities through the Oak Ridge Institute for Science and Education under DOE Contract DE-AC--05-00OR22750. Objectives of the program were to obtain information on the value of medical surveillance among at-risk former radiation workers and to provide long-term internal radiation dosimetry information to the scientific community. This program provided the former radiation workers of the Rocky Flats Environmental Technology Site (formerly Rocky Flats Plant) an opportunity to receive follow-up medical monitoring and a re-evaluation of their internal radiation dose. The former Rocky Flats radiation worker population is distinctive because it was a reasonably stable work force that received occupational exposures, at times substantial, over several decades. This report reflects the summation of health outcomes, statistical analyses, and dose assessment information on former Rocky Flats radiation workers to the date of study termination as of March 2004

  13. The application in detection the position accuracy of the multi-leaf collimator of Varian linear accelerator with dynamic therapy log files

    International Nuclear Information System (INIS)

    Li Changhu; Xu Liming; Teng Jianjian; Ge Wei; Zhang Jun; Ma Guangdong

    2010-01-01

    Objective: To explorer the application in detection the position accuracy of the multileaf collimator of Varian accelerator with dynamic therapy log files. Methods: A pre-designed MLC format files named PMLC for two Varian accelerators, the dynamic treatment log files were recorded 10 times on a different date, and be converted into the MLC format files named DMLC, compared with the original plan PMLC, so we can analysis two files for each leaf position deviation. In addition, we analysis the repeatability of MLC leaves position accuracy between 10 dynalog files of two accelerators. Results: No statistically significant difference between the average position of the 10 times leaf position of the two accelerators,their were 0.29 -0.29 and 0.29 -0.30 (z = -0.77, P=0.442). About 40%, 30%, 20% and 10% of the leaf position deviation was at ≤0.2 mm, 0.3 mm, 0.5 mm and 0.4 mm, respectively. the maximum value was 0.5 mm. More than 86% of the leaf position are completely coincident between 10 dynamic treatment files of two accelerators. The rate of position deviation no more 0. 05 mm was 96. 6% and 97.3%, respectively. And the maximum value was 0.09 mm. Conclusions: Dynamic treatment log file is a splendid tool in testing the actual position of multi-leaf collimator. The multi-leaf collimator of two accelerators be detected are precise and stabilized. (authors)

  14. Trophic transfer of trace metals from the polychaete worm Nereis diversicolor to the polychaete N. virens and the decapod crustacean Palaemonetes varians

    Science.gov (United States)

    Rainbow, P.S.; Poirier, L.; Smith, B.D.; Brix, K.V.; Luoma, S.N.

    2006-01-01

    Diet is an important exposure route for the uptake of trace metals by aquatic invertebrates, with trace metal trophic transfer depending on 2 stages - assimilation and subsequent accumulation by the predator. This study investigated the trophic transfer of trace metals from the sediment-dwelling polychaete worm Nereis diversicolor from metal-rich estuarine sediments in southwestern UK to 2 predators - another polychaete N. virens (Cu, Zn, Pb, Cd, Fe) and the decapod crustacean Palaemonetes varians (Cu, Zn, Pb, Cd, Fe, Ag, As, Mn). N. virens showed net accumulation of Cu, Zn, Pb and Cd from the prey; accumulation increased with increasing prey concentration, but a coefficient of trophic transfer decreased with increasing prey concentration, probably because a higher proportion of accumulated metal in the prey is bound in less trophically available (insoluble) detoxified forms. The trace metal accumulation patterns of P. varians apparently restricted significant net accumulation of metals from the diet of N. diversicolor to just Cd. There was significant mortality of the decapods fed on the diets of metal-rich worms. Metal-rich invertebrates that have accumulated metals from the rich historical store in the sediments of particular SW England estuaries can potentially pass these metals along food chains, with accumulation and total food chain transfer depending on the metal assimilation efficiencies and accumulation patterns of the animal at each trophic level. This trophic transfer may be significant enough to have ecotoxicological effects. ?? Inter-Research 2006.

  15. Monograph on safety in high power and high energy advanced technologies and medical applications of lasers

    International Nuclear Information System (INIS)

    2016-01-01

    This monograph is intended for creating awareness amongst the safety and health professionals of nuclear and radiation facilities on hazards involved in high power and high energy advanced technologies as well as on how development of advanced technologies can benefit the common people

  16. New Region-Scalable Discriminant and Fitting Energy Functional for Driving Geometric Active Contours in Medical Image Segmentation

    Directory of Open Access Journals (Sweden)

    Xuchu Wang

    2014-01-01

    that uses region-scalable discriminant and fitting energy functional for handling the intensity inhomogeneity and weak boundary problems in medical image segmentation. The region-scalable discriminant and fitting energy functional is defined to capture the image intensity characteristics in local and global regions for driving the evolution of active contour. The discriminant term in the model aims at separating background and foreground in scalable regions while the fitting term tends to fit the intensity in these regions. This model is then transformed into a variational level set formulation with a level set regularization term for accurate computation. The new model utilizes intensity information in the local and global regions as much as possible; so it not only handles better intensity inhomogeneity, but also allows more robustness to noise and more flexible initialization in comparison to the original global region and regional-scalable based models. Experimental results for synthetic and real medical image segmentation show the advantages of the proposed method in terms of accuracy and robustness.

  17. Some radiation safety aspects of operating medical generators of VHF electromagnetic energy

    International Nuclear Information System (INIS)

    Bosevski, V.; Radev, S.; Donev, Ch.

    1977-01-01

    The state of radiation safety in physiotherapy practice using very-high-frequency diathermy was studied with regard to personnel and patient protection. A specially devised shielding set to protect patients and personnel is offered for adoption, and the necessity is insistently stressed of prohibiting any patient head or gonad exposure. It is pointed out that the protective set developed may also be used at facilities employing other types of VHF electromagnetic energy sources. (author)

  18. Neutron flux density and secondary-particle energy spectra at the 184-inch synchrocyclotron medical facility

    International Nuclear Information System (INIS)

    Smith, A.R.; Schimmerling, W.; Henson, A.M.; Kanstein, L.L.; McCaslin, J.B.; Stephens, L.D.; Thomas, R.H.; Ozawa, J.; Yeater, F.W.

    1978-07-01

    Helium ions, with an energy of 920 MeV, produced by the 184-inch synchrocyclotron of the Lawrence Berkeley Laboratory are now being used in a pilot series to determine their efficacy in the treatment of tumors of large volume. The techniques for production of the large uniform radiation fields required for these treatments involve the use of beam-limiting collimators and energy degraders. Interaction of the primary beam with these beam components produces secondary charged particles and neutrons. The sources of neutron production in the beam transport system of the alpha-particle beam have been identified and their magnitudes have been determined. Measurements with activation detectors and pulse counters of differing energy responses have been used to determine secondary particle spectra at various locations on the patient table. These spectra are compared to a calculation of neutron production based on best estimates derived from published cross sections. Agreement between the calculated spectra and those derived from experimental measurements is obtained (at the 10 to 20% level) when the presence of charged particles is taken into account. The adsorbed dose in soft tissue is not very sensitive to the shape of the incident neutron energy spectrum, and the values obtained from unfolding the experimental measurements agree with the values obtained from the calculated spectra within the estimated uncertainty of +-25%. These values are about 3 x 10 -3 rad on the beam axis and about 1 x 10 -3 rad at 20 cm or more from the beam axis, per rad deposited by the incident alpha-particle beam. Estimates of upper limit dose to the lens of the eye and red bone marrow are approximately 10 rad and approximately 1 rad, respectively, for a typical treatment plan. The absorbed dose to the lens of the eye is thus well below the threshold value for cataractogenesis estimated for fission neutrons. An upper limit for the risk of leukemia is estimated to be approximately 0.04%

  19. Impact of alcohol and alcohol mixed with energy drinks on non-medical prescription stimulant use in a nationally representative sample of 12th-grade students.

    Science.gov (United States)

    Housman, Jeff M; Williams, Ronald D; Woolsey, Conrad L

    2016-08-01

    Approximately 30% of high school students use energy drinks. Alcohol use and alcohol mixed with energy drink use (AmED) is associated with risky behavior, including non-medical prescription stimulant use. We assessed alcohol-only, AmED and non-medical prescription stimulant use among 12th grade students in the U.S. using a nationally representative secondary data from the 2012 Monitoring the Future Study. Wilcoxon-Mann-Whitney tests and logistic regression analyses were used to determine differences in non-medical prescription stimulant use by students who used alcohol-only versus AmED and to identify covariates of non-medical prescription stimulant use. Pearson-product moment coefficients were used to determine strength of variable relationships. Significant differences were found in frequency of Ritalin (p energy drink and AmED use, as the combined effects of stimulants contained in energy drinks and the depressant effects of alcohol appear to be associated with increased non-medical prescription stimulant use. Research on the influential factors related to energy drinks, alcohol, and non-medical prescription stimulants will help practitioners to more appropriately design prevention and intervention strategies addressing these high-risk behaviors. (Am J Addict 2016;25:378-384). © 2016 American Academy of Addiction Psychiatry.

  20. Evaluation of IsoCal geometric calibration system for Varian linacs equipped with on-board imager and electronic portal imaging device imaging systems.

    Science.gov (United States)

    Gao, Song; Du, Weiliang; Balter, Peter; Munro, Peter; Jeung, Andrew

    2014-05-08

    The purpose of this study is to evaluate the accuracy and reproducibility of the IsoCal geometric calibration system for kilovoltage (kV) and megavoltage (MV) imagers on Varian C-series linear accelerators (linacs). IsoCal calibration starts by imaging a phantom and collimator plate using MV images with different collimator angles, as well as MV and kV images at different gantry angles. The software then identifies objects on the collimator plate and in the phantom to determine the location of the treatment isocenter and its relation to the MV and kV imager centers. It calculates offsets between the positions of the imaging panels and the treatment isocenter as a function of gantry angle and writes a correction file that can be applied to MV and kV systems to correct for those offsets in the position of the panels. We performed IsoCal calibration three times on each of five Varian C-series linacs, each time with an independent setup. We then compared the IsoCal calibrations with a simplified Winston-Lutz (WL)-based system and with a Varian cubic phantom (VC)-based system. The maximum IsoCal corrections ranged from 0.7 mm to 1.5 mm for MV and 0.9 mm to 1.8 mm for kV imagers across the five linacs. The variations in the three calibrations for each linac were less than 0.2 mm. Without IsoCal correction, the WL results showed discrepancies between the treatment isocenter and the imager center of 0.9 mm to 1.6 mm (for the MV imager) and 0.5 mm to 1.1 mm (for the kV imager); with IsoCal corrections applied, the differences were reduced to 0.2 mm to 0.6 mm (MV) and 0.3 mm to 0.6 mm (kV) across the five linacs. The VC system was not as precise as the WL system, but showed similar results, with discrepancies of less than 1.0 mm when the IsoCal corrections were applied. We conclude that IsoCal is an accurate and consistent method for calibration and periodic quality assurance of MV and kV imaging systems.

  1. Energy efficient medium access protocol for wireless medical body area sensor networks.

    Science.gov (United States)

    Omeni, O; Wong, A; Burdett, A J; Toumazou, C

    2008-12-01

    This paper presents a novel energy-efficient MAC Protocol designed specifically for wireless body area sensor networks (WBASN) focused towards pervasive healthcare applications. Wireless body area networks consist of wireless sensor nodes attached to the human body to monitor vital signs such as body temperature, activity or heart-rate. The network adopts a master-slave architecture, where the body-worn slave node periodically sends sensor readings to a central master node. Unlike traditional peer-to-peer wireless sensor networks, the nodes in this biomedical WBASN are not deployed in an ad hoc fashion. Joining a network is centrally managed and all communications are single-hop. To reduce energy consumption, all the sensor nodes are in standby or sleep mode until the centrally assigned time slot. Once a node has joined a network, there is no possibility of collision within a cluster as all communication is initiated by the central node and is addressed uniquely to a slave node. To avoid collisions with nearby transmitters, a clear channel assessment algorithm based on standard listen-before-transmit (LBT) is used. To handle time slot overlaps, the novel concept of a wakeup fallback time is introduced. Using single-hop communication and centrally controlled sleep/wakeup times leads to significant energy reductions for this application compared to more ldquoflexiblerdquo network MAC protocols such as 802.11 or Zigbee. As duty cycle is reduced, the overall power consumption approaches the standby power. The protocol is implemented in hardware as part of the Sensiumtrade system-on-chip WBASN ASIC, in a 0.13- mum CMOS process.

  2. Role of excitons in the energy resolution of scintillators used for medical imaging

    Energy Technology Data Exchange (ETDEWEB)

    Singh, Jai [School of Engineering and IT, B-purple-12, Faculty of EHS, Charles Darwin University, Darwin NT 0909 (Australia)

    2010-11-01

    Theoretical investigations suggest that the nonproportionality in a scintillator is caused by the high excitation density created within the track of an X-ray or {gamma} ray photon entering in a scintillating crystal. In this paper an analytical expression for the scintillator yield is derived. For the case of BaF{sub 2} scintillator the role of excitons created within the {gamma}-ray track in the scintillator yield is studied. By comparing the results of two theories an analytical expression is also derived for an energy parameter which could otherwise only be determined by fitting the theoretical yield to the experimental data.

  3. Role of excitons in the energy resolution of scintillators used for medical imaging

    International Nuclear Information System (INIS)

    Singh, Jai

    2010-01-01

    Theoretical investigations suggest that the nonproportionality in a scintillator is caused by the high excitation density created within the track of an X-ray or γ ray photon entering in a scintillating crystal. In this paper an analytical expression for the scintillator yield is derived. For the case of BaF 2 scintillator the role of excitons created within the γ-ray track in the scintillator yield is studied. By comparing the results of two theories an analytical expression is also derived for an energy parameter which could otherwise only be determined by fitting the theoretical yield to the experimental data.

  4. Electronic tissue compensation achieved with both dynamic and static multileaf collimator in eclipse treatment planning system for Clinac 6 EX and 2100 CD Varian linear accelerators: Feasibility and dosimetric study

    Directory of Open Access Journals (Sweden)

    Kinhikar Rajesh

    2007-01-01

    Full Text Available Dynamic multileaf collimator (DMLC and static multileaf collimator (SMLC, along with three-dimensional treatment planning system (3-D TPS, open the possibility of tissue compensation. A method using electronic tissue compensator (ETC has been implemented in Eclipse 3-D TPS (V 7.3, Varian Medical Systems, Palo Alto, USA at our center. The ETC was tested for head and neck conformal radiotherapy planning. The purpose of this study was to verify the feasibility of DMLC and SMLC in head and neck field irradiation for delivering homogeneous dose in the midplane at a pre-defined depth. In addition, emphasis was given to the dosimetric aspects in commissioning ETC in Eclipse. A Head and Neck Phantom (The Phantom Laboratory, USA was used for the dosimetric verification. Planning was carried out for both DMLC and SMLC ETC plans. The dose calculated at central axis by eclipse with DMLC and SMLC was noted. This was compared with the doses measured on machine with ion chamber and thermoluminescence dosimetry (TLD. The calculated isodose curves and profiles were compared with the measured ones. The dose profiles along the two major axes from Eclipse were also compared with the profiles obtained from Amorphous Silicon (AS500 Electronic portal imaging device (EPID on Clinac 6 EX machine. In uniform dose regions, measured dose values agreed with the calculated doses within 3%. Agreement between calculated and measured isodoses in the dose gradient zone was within 3 mm. The isodose curves and the profiles were found to be in good agreement with the measured curves and profiles. The measured and the calculated dose profiles along the two major axes were flat for both DMLC and SMLC. The dosimetric verification of ETC for both the linacs demonstrated the feasibility and the accuracy of the ETC treatment modality for achieving uniform dose distributions. Therefore, ETC can be used as a tool in head and neck treatment planning optimization for improved dose uniformity.

  5. Dose levels due to neutrons in the vicinity of high energy medical accelerators

    International Nuclear Information System (INIS)

    McGinley, P.H.; Wood, M.; Sohrabi, M.; Mills, M.; Rodriguez, R.

    1976-01-01

    High energy photons are generated for use in radiation therapy by the decelleration of electrons in metal targets. Fast neutrons are also generated as a result of (γ, n) and (e, e'n) interactions in the target, beam compensator filter, and collimator material. In this work the adsorbed dose to neutrons was measured at the center of a 10 x 10 cm photon beam and 5 cm outside of the beam edge for a number of treatment units. Dose levels due to slow and fast neutrons were also established outside of the treatment rooms and a Bonner sphere neutron spectrometer system was employed to determine the neutron energy spectrum due to stray neutron radiation at each accelerator. For the linac it was found that the neutron dose at the beam center was 0.0039% of the photon dose and values of 0.049% and 0.053% were observed for the Allis Chalmers betatron and the Brown Boveri Betatron. Dose equivalent rates in the range of 0.3 to 22.5 mrem/hr were measured for points outside the treatment rooms when the accelerators were operated at a photon dose rate of 100 rad/min at the treatment position

  6. A reviewed technique for total body electron therapy using a Varian Clinac 2100C/D high dose rate treatment beam facility

    International Nuclear Information System (INIS)

    Oliver, L.D.; Xuereb, E.M.A.; Last, V.; Hunt, P.B.; Wilfert, A.

    1996-01-01

    Our (Royal North Shore Hospital) most recent linear accelerator acquisition is a Varian Clinac 2100C/D which has a high dose rate (approximately 25Gy per minute at 1 metre) total body electron option. We investigated the physical characteristics of the electron beam to develop a suitable method of treatment for total body electron therapy. The useful electron beam width is defined as 80cm above and below the reference height. Measurements of the electron dose received from the two angled electron beams showed a critical dependence on the gantry angles. The treatment protocol uses ten different patient angles, fractionated into directly opposing fields and treated seuqentially each day. A full cycle of treatment is completed in five days. (author)

  7. Construction of lead glass tubing matrices for applications in medical physics and high energy physics

    International Nuclear Information System (INIS)

    Schwartz, G.; Conti, M.; Del Guerra, A.; Cinti, M.; Di Fino, M.; Habel, R.

    1985-01-01

    Honeycomb matrices which act both as gamma ray converter/radiator and electron drift structures have been manufactured from lead glass tubing of high density (5-6 g/cm 3 ). Baking the tubing in a reducing atmosphere produces a resistive metallic layer which can be used as a continuous voltage divider for drift field shaping. The application of a multiwire proportional chamber/converter detector to positron emission tomography is described; arrays of lead glass capillaries ( < 1.0 mm inner diameter) are used as converter for the 511 keV annihilation photons. Another application is under study in high energy physics, a high density projection chamber in electromagnetic calorimetry. The various phases of the construction of these lead glass matrices for both applications are described in detail

  8. Design of planning target volume margin using an active breathing control and Varian image-guided radiotherapy (IGRT) system in unresectable liver tumor

    International Nuclear Information System (INIS)

    Yue Jinbo; Yu Jinming; Liu Jing; Liu Tonghai; Yin Yong; Shi Xuetao; Song Jinlong

    2007-01-01

    Objective: To define the planning target volume(PTV) margin with an active breathing control (ABC) and the Varian image-guided radiotherapy (IGRT) system. Methods: Thirteen patients with liver cancer were treated with radiotherapy from May 2006 to September 2006. Prior to radiotherapy, all patients had undergone transarterial chemoembolization (TACE) by infusing a mixture of iodized oil contrast medium and chemotherapeutic agents, kV fluoroscopy was used to measure the potential motion of lipiodol spot positions during ABC breath-holds. ABC was used for planning CT scan and radiation delivery, with the breath held at the same phase of the respiratory cycle (near end-exhalation). Cone beam CT (CBCT) was taken using Varian IGRT system, which was then compared online with planning CT using a 3 D-3 D matching tool. Analysis relied on lipiodol spots on planning CT and CBCT manually. The treatment table was moved to produce acceptable setup before treatment delivery. Repeated CBCT image and another analysis were obtained after irradiation. Results: No motion of the intrahepatic tumor was observed on fluoroscopy during ABC breath-holds. The estimated required PTV margins, calculated according to the Stroom formula, were 4.4 mm, 5.3 mm and 7.8 mm in the x, y and z axis directions before radiotherapy. The corresponding parameters were 2.5m, 2.6 mm and 3.9 mm after radiotherapy. Conclusions: We have adopted a PTV margin of 5 mm, 6 mm and 8 mm in the x, y and z axis directions with ABC, and 3,3 and 4 mm with ABC and on-line kilovoltage CBCT. (authors)

  9. An EPID-based method for comprehensive verification of gantry, EPID and the MLC carriage positional accuracy in Varian linacs during arc treatments

    International Nuclear Information System (INIS)

    Rowshanfarzad, Pejman; McGarry, Conor K; Barnes, Michael P; Sabet, Mahsheed; Ebert, Martin A

    2014-01-01

    In modern radiotherapy, it is crucial to monitor the performance of all linac components including gantry, collimation system and electronic portal imaging device (EPID) during arc deliveries. In this study, a simple EPID-based measurement method has been introduced in conjunction with an algorithm to investigate the stability of these systems during arc treatments with the aim of ensuring the accuracy of linac mechanical performance. The Varian EPID sag, gantry sag, changes in source-to-detector distance (SDD), EPID and collimator skewness, EPID tilt, and the sag in MLC carriages as a result of linac rotation were separately investigated by acquisition of EPID images of a simple phantom comprised of 5 ball-bearings during arc delivery. A fast and robust software package was developed for automated analysis of image data. Twelve Varian linacs of different models were investigated. The average EPID sag was within 1 mm for all tested linacs. All machines showed less than 1 mm gantry sag. Changes in SDD values were within 1.7 mm except for three linacs of one centre which were within 9 mm. Values of EPID skewness and tilt were negligible in all tested linacs. The maximum sag in MLC leaf bank assemblies was around 1 mm. The EPID sag showed a considerable improvement in TrueBeam linacs. The methodology and software developed in this study provide a simple tool for effective investigation of the behaviour of linac components with gantry rotation. It is reproducible and accurate and can be easily performed as a routine test in clinics

  10. SU-F-J-14: Kilovoltage Cone-Beam CT Dose Estimation of Varian On-Board Imager Using GMctdospp Monte Carlo Framework

    Energy Technology Data Exchange (ETDEWEB)

    Kim, S; Rangaraj, D [Baylor Scott & White Health, Temple, TX (United States)

    2016-06-15

    Purpose: Although cone-beam CT (CBCT) imaging became popular in radiation oncology, its imaging dose estimation is still challenging. The goal of this study is to assess the kilovoltage CBCT doses using GMctdospp - an EGSnrc based Monte Carlo (MC) framework. Methods: Two Varian OBI x-ray tube models were implemented in the GMctpdospp framework of EGSnrc MC System. The x-ray spectrum of 125 kVp CBCT beam was acquired from an EGSnrc/BEAMnrc simulation and validated with IPEM report 78. Then, the spectrum was utilized as an input spectrum in GMctdospp dose calculations. Both full and half bowtie pre-filters of the OBI system were created by using egs-prism module. The x-ray tube MC models were verified by comparing calculated dosimetric profiles (lateral and depth) to ion chamber measurements for a static x-ray beam irradiation to a cuboid water phantom. An abdominal CBCT imaging doses was simulated in GMctdospp framework using a 5-year-old anthropomorphic phantom. The organ doses and effective dose (ED) from the framework were assessed and compared to the MOSFET measurements and convolution/superposition dose calculations. Results: The lateral and depth dose profiles in the water cuboid phantom were well matched within 6% except a few areas - left shoulder of the half bowtie lateral profile and surface of water phantom. The organ doses and ED from the MC framework were found to be closer to MOSFET measurements and CS calculations within 2 cGy and 5 mSv respectively. Conclusion: This study implemented and validated the Varian OBI x-ray tube models in the GMctdospp MC framework using a cuboid water phantom and CBCT imaging doses were also evaluated in a 5-year-old anthropomorphic phantom. In future study, various CBCT imaging protocols will be implemented and validated and consequently patient CT images will be used to estimate the CBCT imaging doses in patients.

  11. A study on radiation safety measures for the use of high-energy beta-ray sources in medical fields

    Energy Technology Data Exchange (ETDEWEB)

    Park, Jae Woo; Yang, Jeong Seon; Kim, Hyeon Jo [Cheju National Univ., Cheju (Korea, Republic of)

    2000-12-15

    The scope of this study consists of : an investigation of the current application status of medical radioisotopes, Sr-90, Ho-166, Re-188, which emit beta-rays of energy greater than 1.5 Mev, analyses of the environments under which the above isotopes are used, estimation of personal radiation doses by using the MCNP-4C computer code for the situations in which high radiation doses might be probable, review of the USA's regulations related to safe use of the radioisotopes, investigation of past over-expose cases reported in the internet, analysis of the current domestic regulations, suggestion of safety measures necessary for the use of the radioisotopes.

  12. Experimental investigations of the neutron contamination in high-energy photon fields at medical linear accelerators

    International Nuclear Information System (INIS)

    Brunckhorst, Elin

    2009-01-01

    The scope of this thesis was to develop a device for the detection of the photoneutron dose inside the high-energy photon field. The photoneutron contamination of a Siemens PRIMUS linear accelerator was investigated in detail in its 15 MV photon mode. The experimental examinations were performed with three ionisation chambers (a tissue equivalent chamber, a magnesium chamber and a 10 B-coated magnesium chamber) and two types of thermoluminescence detectors (enriched with 6 Li and 7 Li, respectively). The detectors have different sensitivities to photons and neutrons and their combination allows the dose separation in a mixed neutron/photon field. The application of the ionisation chamber system, as well as the present TLD system for photoneutron detection in high-energy photon beams is a new approach. The TLD neutron sensitivity was found to be too low for a measurement inside the open photon field and the further investigation focused on the ionisation chambers. The three ionisation chambers were calibrated at different photon and neutron sources and a the borated magnesium chamber showed a very high response to thermal neutrons. For a cross check of the calibration, the three chambers were also used for dose separation of a boron neutron capture therapy beam where the exact determination of the thermal neutron dose is essential. Very accurate results were achieved for the thermal neutron dose component. At the linear accelerator the chamber system was reduced to a paired chamber system utilising the two magnesium chambers, since the fast neutron component was to small to be separated. The neutron calibration of the three chambers could not be applied, instead a conversion of measured thermal neutron signal by the borated chamber to Monte Carlo simulated total neutron dose was performed. Measurements for open fields in solid water and liquid water were performed with the paired chamber system. In larger depths the neutron dose could be determined with an

  13. Experimental investigations of the neutron contamination in high-energy photon fields at medical linear accelerators

    Energy Technology Data Exchange (ETDEWEB)

    Brunckhorst, Elin

    2009-02-26

    The scope of this thesis was to develop a device for the detection of the photoneutron dose inside the high-energy photon field. The photoneutron contamination of a Siemens PRIMUS linear accelerator was investigated in detail in its 15 MV photon mode. The experimental examinations were performed with three ionisation chambers (a tissue equivalent chamber, a magnesium chamber and a {sup 10}B-coated magnesium chamber) and two types of thermoluminescence detectors (enriched with {sup 6}Li and {sup 7}Li, respectively). The detectors have different sensitivities to photons and neutrons and their combination allows the dose separation in a mixed neutron/photon field. The application of the ionisation chamber system, as well as the present TLD system for photoneutron detection in high-energy photon beams is a new approach. The TLD neutron sensitivity was found to be too low for a measurement inside the open photon field and the further investigation focused on the ionisation chambers. The three ionisation chambers were calibrated at different photon and neutron sources and a the borated magnesium chamber showed a very high response to thermal neutrons. For a cross check of the calibration, the three chambers were also used for dose separation of a boron neutron capture therapy beam where the exact determination of the thermal neutron dose is essential. Very accurate results were achieved for the thermal neutron dose component. At the linear accelerator the chamber system was reduced to a paired chamber system utilising the two magnesium chambers, since the fast neutron component was to small to be separated. The neutron calibration of the three chambers could not be applied, instead a conversion of measured thermal neutron signal by the borated chamber to Monte Carlo simulated total neutron dose was performed. Measurements for open fields in solid water and liquid water were performed with the paired chamber system. In larger depths the neutron dose could be determined

  14. New medical imaging systems exploiting the energy dispersive X-ray diffraction with spectrometric CdZnTe based detector

    International Nuclear Information System (INIS)

    Barbes, Damien

    2016-01-01

    This thesis studies the interest of measuring the coherent scattering of X-rays for breast diagnosis imaging. Nowadays, most of X-ray-based medical imaging techniques use the information of X-rays attenuation through the tissues. It is the case for mammography, the most common breast imaging modality. The recent emergence of energy resolved detectors (based on semiconductors in particular) allows to consider using another phenomenon: the coherent X-ray scattering. Measurement of diffracted spectra can provide new information related to the molecular structure of the examined tissues, in order to improve their characterization and therefore improve the final diagnosis. Two modalities are considered: the breast cancer detection in vivo, following a suspicious mammography result, or biopsy analysis. The coherent scattering measurement system developed during this thesis work uses energy-resolved CdZnTe-based detectors, these detectors combining performances (energy resolution, sensitivity, spatial resolution, and compactness) promising for clinical application. This system is also based on the detector pixelation, which allows to provide an imaging modality capable of characterizing analyzed materials or tissues in one direction without any translation or rotation. A complete study of the measurement system is proposed in this thesis, structured in three main parts: modeling and simulation of the system, development of the processing of the data measured by the detector in order to image and characterize the analyzed sample and finally, designing of a new and more complex experimental setup based on a whole detector and multi-slit collimation system. An experimental validation is proposed for each of these three parts. (author) [fr

  15. Energy

    International Nuclear Information System (INIS)

    Meister, F.; Ott, F.

    2002-01-01

    This chapter gives an overview of the current energy economy in Austria. The Austrian political aims of sustainable development and climate protection imply a reorientation of the Austrian energy policy as a whole. Energy consumption trends (1993-1998), final energy consumption by energy carrier (indexed data 1993-1999), comparative analysis of useful energy demand (1993 and 1999) and final energy consumption of renewable energy sources by sector (1996-1999) in Austria are given. The necessary measures to be taken in order to reduce the energy demand and increased the use of renewable energy are briefly mentioned. Figs. 5. (nevyjel)

  16. Energy

    International Nuclear Information System (INIS)

    Meister, F.

    2001-01-01

    This chapter of the environmental control report deals with the environmental impact of energy production, energy conversion, atomic energy and renewable energy. The development of the energy consumption in Austria for the years 1993 to 1999 is given for the different energy types. The development of the use of renewable energy sources in Austria is given, different domestic heat-systems are compared, life cycles and environmental balance are outlined. (a.n.)

  17. Perceived Stress and Coffee and Energy Drink Consumption Predict Poor Sleep Quality in Podiatric Medical Students A Cross-sectional Study.

    Science.gov (United States)

    Sawah, Mohomad Al; Ruffin, Naeemah; Rimawi, Mohammad; Concerto, Carmen; Aguglia, Eugenio; Chusid, Eileen; Infortuna, Carmenrita; Battaglia, Fortunato

    2015-09-01

    A cross-sectional survey administered to first- and second-year podiatric medical students aimed to investigate the effect of coffee intake, energy drink consumption, and perceived stress on sleep quality in medical students during their preclinical studies. Ninety-eight of 183 students contacted (53.6%) completed a questionnaire comprising standard instruments measuring sleep quality (Pittsburgh Sleep Quality Index), daytime sleepiness (Epworth Sleepiness scale), and perceived stress (ten-item Perceived Stress Scale). Furthermore, we investigated coffee and energy drink consumption. Logistic regression was conducted to identify factors associated with poor sleep quality and the relation between sleep quality and academic performance (grade point average). High prevalences of poor sleep quality, excessive daytime sleepiness, and perceived stress were reported. In addition, higher odds of developing poor sleep quality were associated with coffee and energy drink intake, perceived stress, and excessive daytime sleepiness. The total Pittsburgh Sleep Quality Index score was inversely correlated with grade point average. First- and second-year podiatric medical students have poor sleep quality. Further research is needed to identify effective strategies to reduce stress and decrease coffee and energy drink intake to minimize their negative effect on sleep quality and academic performance in podiatric medical students.

  18. CPU time optimization and precise adjustment of the Geant4 physics parameters for a VARIAN 2100 C/D gamma radiotherapy linear accelerator simulation using GAMOS

    Science.gov (United States)

    Arce, Pedro; Lagares, Juan Ignacio

    2018-02-01

    We have verified the GAMOS/Geant4 simulation model of a 6 MV VARIAN Clinac 2100 C/D linear accelerator by the procedure of adjusting the initial beam parameters to fit the percentage depth dose and cross-profile dose experimental data at different depths in a water phantom. Thanks to the use of a wide range of field sizes, from 2  ×  2 cm2 to 40  ×  40 cm2, a small phantom voxel size and high statistics, fine precision in the determination of the beam parameters has been achieved. This precision has allowed us to make a thorough study of the different physics models and parameters that Geant4 offers. The three Geant4 electromagnetic physics sets of models, i.e. Standard, Livermore and Penelope, have been compared to the experiment, testing the four different models of angular bremsstrahlung distributions as well as the three available multiple-scattering models, and optimizing the most relevant Geant4 electromagnetic physics parameters. Before the fitting, a comprehensive CPU time optimization has been done, using several of the Geant4 efficiency improvement techniques plus a few more developed in GAMOS.

  19. SU-F-T-656: Monte Carlo Study On Air Activation Around a Medical Electron Linac

    International Nuclear Information System (INIS)

    Horst, F; Fehrenbacher, G; Zink, K

    2016-01-01

    Purpose: In high energy photon therapy, several radiation protection issues result from photonuclear reactions. The activation of air - directly by photonuclear reactions as well as indirectly by capture of photoneutrons generated inside the linac head - is a major point of concern for the medical staff. The purpose of this study was to estimate the annual effective dose to medical workers due to activated air around a medical high energy electron linac by means of Monte Carlo simulations. Methods: The treatment head of a Varian Clinac in 18 MV-X mode as well as the surrounding concrete bunker were modeled and the radiation transport was simulated using the Monte Carlo code FLUKA, starting from the primary electron striking the bremsstrahlung target. The activation yields in air from photo-disintegration of O-16 and N-14 nuclei as well as from neutron capture on Ar-40 nuclei were obtained from the simulations. The activation build-up, radioactive decay and air ventilation were studied using a mathematical model. The annual effective dose to workers was estimated by using published isotope specific conversion factors. Results: The oxygen and nitrogen activation yields were in contrast to the argon activation yield found to be field size dependent. The impact of the treatment room ventilation on the different air activation products was investigated and quantified. An estimate with very conservative assumptions gave an annual effective dose to workers of < 1 mSv/a. Conclusion: From the results of this study it can be concluded that the contribution of air activation to the radiation exposure to medical workers should be negligible in modern photon therapy, especially when it is compared to the dose due to prompt neutrons and the activation of heavy solid materials such as the jaws and the collimators inside the linac head.

  20. SU-F-T-656: Monte Carlo Study On Air Activation Around a Medical Electron Linac

    Energy Technology Data Exchange (ETDEWEB)

    Horst, F [Institute of Medical Physics and Radiation Protection, University of Applied Sciences, Giessen (Germany); GSI Helmholtz Centre for Heavy Ion Research, Darmstadt (Germany); Fehrenbacher, G [GSI Helmholtz Centre for Heavy Ion Research, Darmstadt (Germany); Zink, K [Institute of Medical Physics and Radiation Protection, University of Applied Sciences, Giessen (Germany); University Hospital Giessen-Marburg, Marburg (Germany)

    2016-06-15

    Purpose: In high energy photon therapy, several radiation protection issues result from photonuclear reactions. The activation of air - directly by photonuclear reactions as well as indirectly by capture of photoneutrons generated inside the linac head - is a major point of concern for the medical staff. The purpose of this study was to estimate the annual effective dose to medical workers due to activated air around a medical high energy electron linac by means of Monte Carlo simulations. Methods: The treatment head of a Varian Clinac in 18 MV-X mode as well as the surrounding concrete bunker were modeled and the radiation transport was simulated using the Monte Carlo code FLUKA, starting from the primary electron striking the bremsstrahlung target. The activation yields in air from photo-disintegration of O-16 and N-14 nuclei as well as from neutron capture on Ar-40 nuclei were obtained from the simulations. The activation build-up, radioactive decay and air ventilation were studied using a mathematical model. The annual effective dose to workers was estimated by using published isotope specific conversion factors. Results: The oxygen and nitrogen activation yields were in contrast to the argon activation yield found to be field size dependent. The impact of the treatment room ventilation on the different air activation products was investigated and quantified. An estimate with very conservative assumptions gave an annual effective dose to workers of < 1 mSv/a. Conclusion: From the results of this study it can be concluded that the contribution of air activation to the radiation exposure to medical workers should be negligible in modern photon therapy, especially when it is compared to the dose due to prompt neutrons and the activation of heavy solid materials such as the jaws and the collimators inside the linac head.

  1. Energy aspects of leisure time, personal and medical care, communication and smoking: A possible energy reduction for households; Energieaspecten van vrije-tijdsbesteding, verzorging, communicatie en roken: Een mogelijke energiereductie bij huishoudens

    Energy Technology Data Exchange (ETDEWEB)

    De Paauw, K.F.B.

    1995-06-01

    The energy consumption of consumer expenditures is discussed. Energy consumption per unit of product or activity is calculated for leisure time, personal and medical care, communications, and smoking. In this report special attention is paid to leisure time, subdivided into holidays, day trips and other leisure time activities, focusing on household functions. For the consumer expenditures regarding care, communication and smoking a few products are considered in more detail or calculated by means of the updated version of the Energy Analysis Program. Besides the purchased product or activity itself, travelling and direct and indirect energy consumption are often involved. Most of the energy consumption is realized by travelling, so that options to reduce the energy consumption of leisure time activities can be found there. 37 tabs., 6 appendices, 57 refs.

  2. Energy

    International Nuclear Information System (INIS)

    Bobin, J.L.

    1996-01-01

    Object of sciences and technologies, energy plays a major part in economics and relations between nations. Jean-Louis Bobin, physicist, analyses the relations between man and energy and wonders about fears that delivers nowadays technologies bound to nuclear energy and about the fear of a possible shortage of energy resources. (N.C.). 17 refs., 14 figs., 2 tabs

  3. Energy

    CERN Document Server

    Foland, Andrew Dean

    2007-01-01

    Energy is the central concept of physics. Unable to be created or destroyed but transformable from one form to another, energy ultimately determines what is and isn''t possible in our universe. This book gives readers an appreciation for the limits of energy and the quantities of energy in the world around them. This fascinating book explores the major forms of energy: kinetic, potential, electrical, chemical, thermal, and nuclear.

  4. An MCNP-based model of a medical linear accelerator x-ray photon beam.

    Science.gov (United States)

    Ajaj, F A; Ghassal, N M

    2003-09-01

    The major components in the x-ray photon beam path of the treatment head of the VARIAN Clinac 2300 EX medical linear accelerator were modeled and simulated using the Monte Carlo N-Particle radiation transport computer code (MCNP). Simulated components include x-ray target, primary conical collimator, x-ray beam flattening filter and secondary collimators. X-ray photon energy spectra and angular distributions were calculated using the model. The x-ray beam emerging from the secondary collimators were scored by considering the total x-ray spectra from the target as the source of x-rays at the target position. The depth dose distribution and dose profiles at different depths and field sizes have been calculated at a nominal operating potential of 6 MV and found to be within acceptable limits. It is concluded that accurate specification of the component dimensions, composition and nominal accelerating potential gives a good assessment of the x-ray energy spectra.

  5. SU-E-T-317: The Development of a DIBH Technique for Left Sided Breast Patients Undergoing Radiation Therapy Utilizing Varians RPM System in a Community Hospital

    International Nuclear Information System (INIS)

    Hasson, B; Young, M; Workie, D; Geraghty, C

    2014-01-01

    Purpose: To develop and implement a Deep Inhalation Breath Hold program (DIBH) for treatment of patients with Left-sided breast cancer in a community hospital. Methods: All patients with left sided breast cancer underwent a screening free breathing CT. Evaluation of the conventional tangent treatment fields and the heart was conducted. If the heart would not be excluded using tangents, the patient then received DIBH breathe coaching. The patients returned for a 4D CT simulation. The patients breathing cycle was monitored using the Varian Real-Time position ManagementTM (RPM) system to assess duration of DIBH, amplitude, phase and recovery time to normal breathing. Then a DIBH CT was obtained at the desired amplitude. Duplicate plans were developed for both free breathing and DIBH on the Eclipse planning system and comparison DVH's were created. The plan that provided the prescribed treatment coverage and the least doses to the OAR (heart, Lt. Lung) was determined. Those patients selected to receive treatment with DIBH were set up for treatment, and breathing was monitored using the RPM system. Practice trials were used to confirm that the amplitude, phase and recovery were consistent with findings from simulation. Results: 10 patients have been treated using the DIBH procedure in our clinic. The DIBH patients had an average increase of 80% lung volume on DIBH, decreased lung volume receiving 50% of the dose, and decreases in the V20 dose. Significant reduction in the maximum and mean dose to the heart, as well as the dose to 1CC of the volume for the DIBH plans. Conclusion: Using the RPM system already available in the clinic, staff training, and patient coaching a simple DIBH program was setup. The use of DIBH has shown promise in reducing doses to the critical organs while maintaining PTV coverage for left sided breast treatments

  6. SU-E-T-317: The Development of a DIBH Technique for Left Sided Breast Patients Undergoing Radiation Therapy Utilizing Varians RPM System in a Community Hospital

    Energy Technology Data Exchange (ETDEWEB)

    Hasson, B; Young, M; Workie, D; Geraghty, C [Anne Arundel Medical Center, Annapolis, MD (United States)

    2014-06-01

    Purpose: To develop and implement a Deep Inhalation Breath Hold program (DIBH) for treatment of patients with Left-sided breast cancer in a community hospital. Methods: All patients with left sided breast cancer underwent a screening free breathing CT. Evaluation of the conventional tangent treatment fields and the heart was conducted. If the heart would not be excluded using tangents, the patient then received DIBH breathe coaching. The patients returned for a 4D CT simulation. The patients breathing cycle was monitored using the Varian Real-Time position ManagementTM (RPM) system to assess duration of DIBH, amplitude, phase and recovery time to normal breathing. Then a DIBH CT was obtained at the desired amplitude. Duplicate plans were developed for both free breathing and DIBH on the Eclipse planning system and comparison DVH's were created. The plan that provided the prescribed treatment coverage and the least doses to the OAR (heart, Lt. Lung) was determined. Those patients selected to receive treatment with DIBH were set up for treatment, and breathing was monitored using the RPM system. Practice trials were used to confirm that the amplitude, phase and recovery were consistent with findings from simulation. Results: 10 patients have been treated using the DIBH procedure in our clinic. The DIBH patients had an average increase of 80% lung volume on DIBH, decreased lung volume receiving 50% of the dose, and decreases in the V20 dose. Significant reduction in the maximum and mean dose to the heart, as well as the dose to 1CC of the volume for the DIBH plans. Conclusion: Using the RPM system already available in the clinic, staff training, and patient coaching a simple DIBH program was setup. The use of DIBH has shown promise in reducing doses to the critical organs while maintaining PTV coverage for left sided breast treatments.

  7. SU-G-201-13: Investigation of Dose Variation Induced by HDR Ir-192 Source Global Shift Within the Varian Ring Applicator Using Monte Carlo Methods

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Y; Cai, J; Meltsner, S; Chang, Z; Craciunescu, O [Duke University Medical Center, Durham, NC (United States)

    2016-06-15

    Purpose: The Varian tandem and ring applicators are used to deliver HDR Ir-192 brachytherapy for cervical cancer. The source path within the ring is hard to predict due to the larger interior ring lumen. Some studies showed the source could be several millimeters different from planned positions, while other studies demonstrated minimal dosimetric impact. A global shift can be applied to limit the effect of positioning offsets. The purpose of this study was to assess the necessities of implementing a global source shift using Monte Carlo (MC) simulations. Methods: The MCNP5 radiation transport code was used for all MC simulations. To accommodate TG-186 guidelines and eliminate inter-source attenuation, a BrachyVision plan with 10 dwell positions (0.5cm step sizes) was simulated as the summation of 10 individual sources with equal dwell times for simplification. To simplify the study, the tandem was also excluded from the MC model. Global shifts of ±0.1, ±0.3, ±0.5 cm were then simulated as distal and proximal from the reference positions. Dose was scored in water for all MC simulations and was normalized to 100% at the normalization point 0.5 cm from the cap in the ring plane. For dose comparison, Point A was 2 cm caudal from the buildup cap and 2 cm lateral on either side of the ring axis. With seventy simulations, 108 photon histories gave a statistical uncertainties (k=1) <2% for (0.1 cm)3 voxels. Results: Compared to no global shift, average Point A doses were 0.0%, 0.4%, and 2.2% higher for distal global shifts, and 0.4%, 2.8%, and 5.1% higher for proximal global shifts, respectively. The MC Point A doses differed by < 1% when compared to BrachyVision. Conclusion: Dose variations were not substantial for ±0.3 cm global shifts, which is common in clinical practice.

  8. SU-G-201-13: Investigation of Dose Variation Induced by HDR Ir-192 Source Global Shift Within the Varian Ring Applicator Using Monte Carlo Methods

    International Nuclear Information System (INIS)

    Yang, Y; Cai, J; Meltsner, S; Chang, Z; Craciunescu, O

    2016-01-01

    Purpose: The Varian tandem and ring applicators are used to deliver HDR Ir-192 brachytherapy for cervical cancer. The source path within the ring is hard to predict due to the larger interior ring lumen. Some studies showed the source could be several millimeters different from planned positions, while other studies demonstrated minimal dosimetric impact. A global shift can be applied to limit the effect of positioning offsets. The purpose of this study was to assess the necessities of implementing a global source shift using Monte Carlo (MC) simulations. Methods: The MCNP5 radiation transport code was used for all MC simulations. To accommodate TG-186 guidelines and eliminate inter-source attenuation, a BrachyVision plan with 10 dwell positions (0.5cm step sizes) was simulated as the summation of 10 individual sources with equal dwell times for simplification. To simplify the study, the tandem was also excluded from the MC model. Global shifts of ±0.1, ±0.3, ±0.5 cm were then simulated as distal and proximal from the reference positions. Dose was scored in water for all MC simulations and was normalized to 100% at the normalization point 0.5 cm from the cap in the ring plane. For dose comparison, Point A was 2 cm caudal from the buildup cap and 2 cm lateral on either side of the ring axis. With seventy simulations, 108 photon histories gave a statistical uncertainties (k=1) <2% for (0.1 cm)3 voxels. Results: Compared to no global shift, average Point A doses were 0.0%, 0.4%, and 2.2% higher for distal global shifts, and 0.4%, 2.8%, and 5.1% higher for proximal global shifts, respectively. The MC Point A doses differed by < 1% when compared to BrachyVision. Conclusion: Dose variations were not substantial for ±0.3 cm global shifts, which is common in clinical practice.

  9. SU-E-J-11: Measurement of Eye Lens Dose for Varian On-Board Imaging with Different CBCT Acquisition Techniques

    International Nuclear Information System (INIS)

    Deshpande, S; Dhote, D; Kumar, R; Thakur, K

    2015-01-01

    Purpose: To measure actual patient eye lens dose for different cone beam computed tomography (CBCT) acquisition protocol of Varian’s On Board Imagining (OBI) system using Optically Stimulated Luminescence (OSL) dosimeter and study the eye lens dose with patient geometry and distance of isocenter to the eye lens Methods: OSL dosimeter was used to measure eye lens dose of patient. OSL dosimeter was placed on patient forehead center during CBCT image acquisition to measure eye lens dose. For three different cone beam acquisition protocol (standard dose head, low dose head and high quality head) of Varian On-Board Imaging, eye lens doses were measured. Measured doses were correlated with patient geometry and distance between isocenter to eye lens. Results: Measured eye lens dose for standard dose head was in the range of 1.8 mGy to 3.2 mGy, for high quality head protocol dose was in range of 4.5mGy to 9.9 mGy whereas for low dose head was in the range of 0.3mGy to 0.7mGy. Dose to eye lens is depends upon position of isocenter. For posterioraly located tumor eye lens dose is less. Conclusion: From measured doses it can be concluded that by proper selection of imagining protocol and frequency of imaging, it is possible to restrict the eye lens dose below the new limit set by ICRP. However, undoubted advantages of imaging system should be counter balanced by careful consideration of imaging protocol especially for very intense imaging sequences for Adoptive Radiotherapy or IMRT

  10. Energy

    CERN Document Server

    Robertson, William C

    2002-01-01

    Confounded by kinetic energy? Suspect that teaching about simple machines isn t really so simple? Exasperated by electricity? If you fear the study of energy is beyond you, this entertaining book will do more than introduce you to the topic. It will help you actually understand it. At the book s heart are easy-to-grasp explanations of energy basics work, kinetic energy, potential energy, and the transformation of energy and energy as it relates to simple machines, heat energy, temperature, and heat transfer. Irreverent author Bill Robertson suggests activities that bring the basic concepts of energy to life with common household objects. Each chapter ends with a summary and an applications section that uses practical examples such as roller coasters and home heating systems to explain energy transformations and convection cells. The final chapter brings together key concepts in an easy-to-grasp explanation of how electricity is generated. Energy is the second book in the Stop Faking It! series published by NS...

  11. Energy

    International Nuclear Information System (INIS)

    1975-10-01

    On the occasion of the World Environment Day the Norwegian Ministry for the Environment held a conference on growth problems in energy consumption. The themes which were treated were energy conservation, hydroelectric power, the role of nuclear power, radioactive waste disposal, fossil fuel resources, ecological limits, pollution and international aspects. Nuclear energy forms the main theme of one lecture and an aspect of several others. (JIW)

  12. Energy

    OpenAIRE

    Torriti, Jacopo

    2016-01-01

    The impact of energy policy measures has been assessed with various appraisal and evaluation tools since the 1960s. Decision analysis, environmental impact assessment and strategic environmental assessment are all notable examples of progenitors of Regulatory Impact Assessment (RIA) in the assessment of energy policies, programmes and projects. This chapter provides overview of policy tools which have been historically applied to assess the impacts of energy policies, programmes and projects....

  13. Energies

    International Nuclear Information System (INIS)

    2003-01-01

    In the framework of the National Debate on the energies in a context of a sustainable development some associations for the environment organized a debate on the nuclear interest facing the renewable energies. The first part presents the nuclear energy as a possible solution to fight against the greenhouse effect and the associated problem of the wastes management. The second part gives information on the solar energy and the possibilities of heat and electric power production. A presentation of the FEE (French wind power association) on the situation and the development of the wind power in France, is also provided. (A.L.B.)

  14. WE-G-BRF-05: Feasibility of Markerless Motion Tracking Using Dual Energy Cone Beam Computed Tomography (DE-CBCT) Projections

    International Nuclear Information System (INIS)

    Panfil, J; Patel, R; Surucu, M; Roeske, J

    2014-01-01

    Purpose: To compare markerless template-based tracking of lung tumors using dual energy (DE) cone-beam computed tomography (CBCT) projections versus single energy (SE) CBCT projections. Methods: A RANDO chest phantom with a simulated tumor in the upper right lung was used to investigate the effectiveness of tumor tracking using DE and SE CBCT projections. Planar kV projections from CBCT acquisitions were captured at 60 kVp (4 mAs) and 120 kVp (1 mAs) using the Varian TrueBeam and non-commercial iTools Capture software. Projections were taken at approximately every 0.53° while the gantry rotated. Due to limitations of the phantom, angles for which the shoulders blocked the tumor were excluded from tracking analysis. DE images were constructed using a weighted logarithmic subtraction that removed bony anatomy while preserving soft tissue structures. The tumors were tracked separately on DE and SE (120 kVp) images using a template-based tracking algorithm. The tracking results were compared to ground truth coordinates designated by a physician. Matches with a distance of greater than 3 mm from ground truth were designated as failing to track. Results: 363 frames were analyzed. The algorithm successfully tracked the tumor on 89.8% (326/363) of DE frames compared to 54.3% (197/363) of SE frames (p<0.0001). Average distance between tracking and ground truth coordinates was 1.27 +/− 0.67 mm for DE versus 1.83+/−0.74 mm for SE (p<0.0001). Conclusion: This study demonstrates the effectiveness of markerless template-based tracking using DE CBCT. DE imaging resulted in better detectability with more accurate localization on average versus SE. Supported by a grant from Varian Medical Systems

  15. Treatment vault shielding for a flattening filter-free medical linear accelerator

    Science.gov (United States)

    Kry, Stephen F.; Howell, Rebecca M.; Polf, Jerimy; Mohan, Radhe; Vassiliev, Oleg N.

    2009-03-01

    The requirements for shielding a treatment vault with a Varian Clinac 2100 medical linear accelerator operated both with and without the flattening filter were assessed. Basic shielding parameters, such as primary beam tenth-value layers (TVLs), patient scatter fractions, and wall scatter fractions, were calculated using Monte Carlo simulations of 6, 10 and 18 MV beams. Relative integral target current requirements were determined from treatment planning studies of several disease sites with, and without, the flattening filter. The flattened beam shielding data were compared to data published in NCRP Report No. 151, and the unflattened beam shielding data were presented relative to the NCRP data. Finally, the shielding requirements for a typical treatment vault were determined for a single-energy (6 MV) linac and a dual-energy (6 MV/18 MV) linac. With the exception of large-angle patient scatter fractions and wall scatter fractions, the vault shielding parameters were reduced when the flattening filter was removed. Much of this reduction was consistent with the reduced average energy of the FFF beams. Primary beam TVLs were reduced by 12%, on average, and small-angle scatter fractions were reduced by up to 30%. Head leakage was markedly reduced because less integral target current was required to deliver the target dose. For the treatment vault examined in the current study, removal of the flattening filter reduced the required thickness of the primary and secondary barriers by 10-20%, corresponding to 18 m3 less concrete to shield the single-energy linac and 36 m3 less concrete to shield the dual-energy linac. Thus, a shielding advantage was found when the linac was operated without the flattening filter. This translates into a reduction in occupational exposure and/or the cost and space of shielding.

  16. Treatment vault shielding for a flattening filter-free medical linear accelerator

    Energy Technology Data Exchange (ETDEWEB)

    Kry, Stephen F; Howell, Rebecca M; Polf, Jerimy; Mohan, Radhe; Vassiliev, Oleg N [Department of Radiation Physics, University of Texas M. D. Anderson Cancer Center, Houston, TX (United States)], E-mail: sfkry@mdanderson.org

    2009-03-07

    The requirements for shielding a treatment vault with a Varian Clinac 2100 medical linear accelerator operated both with and without the flattening filter were assessed. Basic shielding parameters, such as primary beam tenth-value layers (TVLs), patient scatter fractions, and wall scatter fractions, were calculated using Monte Carlo simulations of 6, 10 and 18 MV beams. Relative integral target current requirements were determined from treatment planning studies of several disease sites with, and without, the flattening filter. The flattened beam shielding data were compared to data published in NCRP Report No. 151, and the unflattened beam shielding data were presented relative to the NCRP data. Finally, the shielding requirements for a typical treatment vault were determined for a single-energy (6 MV) linac and a dual-energy (6 MV/18 MV) linac. With the exception of large-angle patient scatter fractions and wall scatter fractions, the vault shielding parameters were reduced when the flattening filter was removed. Much of this reduction was consistent with the reduced average energy of the FFF beams. Primary beam TVLs were reduced by 12%, on average, and small-angle scatter fractions were reduced by up to 30%. Head leakage was markedly reduced because less integral target current was required to deliver the target dose. For the treatment vault examined in the current study, removal of the flattening filter reduced the required thickness of the primary and secondary barriers by 10-20%, corresponding to 18 m{sup 3} less concrete to shield the single-energy linac and 36 m{sup 3} less concrete to shield the dual-energy linac. Thus, a shielding advantage was found when the linac was operated without the flattening filter. This translates into a reduction in occupational exposure and/or the cost and space of shielding.

  17. Treatment vault shielding for a flattening filter-free medical linear accelerator

    International Nuclear Information System (INIS)

    Kry, Stephen F; Howell, Rebecca M; Polf, Jerimy; Mohan, Radhe; Vassiliev, Oleg N

    2009-01-01

    The requirements for shielding a treatment vault with a Varian Clinac 2100 medical linear accelerator operated both with and without the flattening filter were assessed. Basic shielding parameters, such as primary beam tenth-value layers (TVLs), patient scatter fractions, and wall scatter fractions, were calculated using Monte Carlo simulations of 6, 10 and 18 MV beams. Relative integral target current requirements were determined from treatment planning studies of several disease sites with, and without, the flattening filter. The flattened beam shielding data were compared to data published in NCRP Report No. 151, and the unflattened beam shielding data were presented relative to the NCRP data. Finally, the shielding requirements for a typical treatment vault were determined for a single-energy (6 MV) linac and a dual-energy (6 MV/18 MV) linac. With the exception of large-angle patient scatter fractions and wall scatter fractions, the vault shielding parameters were reduced when the flattening filter was removed. Much of this reduction was consistent with the reduced average energy of the FFF beams. Primary beam TVLs were reduced by 12%, on average, and small-angle scatter fractions were reduced by up to 30%. Head leakage was markedly reduced because less integral target current was required to deliver the target dose. For the treatment vault examined in the current study, removal of the flattening filter reduced the required thickness of the primary and secondary barriers by 10-20%, corresponding to 18 m 3 less concrete to shield the single-energy linac and 36 m 3 less concrete to shield the dual-energy linac. Thus, a shielding advantage was found when the linac was operated without the flattening filter. This translates into a reduction in occupational exposure and/or the cost and space of shielding.

  18. SU-F-J-42: Comparison of Varian TrueBeam Cone-Beam CT and BrainLab ExacTrac X-Ray for Cranial Radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Li, J; Shi, W; Andrews, D; Werner-Wasik, M; Lu, B; Yu, Y; Dicker, A; Liu, H [Thomas Jefferson University Hospital, Philadelphia, PA (United States)

    2016-06-15

    Purpose: To compare online image registrations of TrueBeam cone-beam CT (CBCT) and BrainLab ExacTrac x-ray imaging systems for cranial radiotherapy. Method: Phantom and patient studies were performed on a Varian TrueBeam STx linear accelerator (Version 2.5), which is integrated with a BrainLab ExacTrac imaging system (Version 6.1.1). The phantom study was based on a Rando head phantom, which was designed to evaluate isocenter-location dependence of the image registrations. Ten isocenters were selected at various locations in the phantom, which represented clinical treatment sites. CBCT and ExacTrac x-ray images were taken when the phantom was located at each isocenter. The patient study included thirteen patients. CBCT and ExacTrac x-ray images were taken at each patient’s treatment position. Six-dimensional image registrations were performed on CBCT and ExacTrac, and residual errors calculated from CBCT and ExacTrac were compared. Results: In the phantom study, the average residual-error differences between CBCT and ExacTrac image registrations were: 0.16±0.10 mm, 0.35±0.20 mm, and 0.21±0.15 mm, in the vertical, longitudinal, and lateral directions, respectively. The average residual-error differences in the rotation, roll, and pitch were: 0.36±0.11 degree, 0.14±0.10 degree, and 0.12±0.10 degree, respectively. In the patient study, the average residual-error differences in the vertical, longitudinal, and lateral directions were: 0.13±0.13 mm, 0.37±0.21 mm, 0.22±0.17 mm, respectively. The average residual-error differences in the rotation, roll, and pitch were: 0.30±0.10 degree, 0.18±0.11 degree, and 0.22±0.13 degree, respectively. Larger residual-error differences (up to 0.79 mm) were observed in the longitudinal direction in the phantom and patient studies where isocenters were located in or close to frontal lobes, i.e., located superficially. Conclusion: Overall, the average residual-error differences were within 0.4 mm in the translational

  19. TH-EF-BRB-10: Dosimetric Validation of a Trajectory Based Cranial SRS Treatment Technique On a Varian TrueBeam Linac

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, B [University of British Columbia, Vancouver, BC (Canada); Vancouver Cancer Centre, Vancouver, BC (Canada); Gete, E [Vancouver Cancer Centre, Vancouver, BC (Canada)

    2016-06-15

    Purpose: This work investigates the dosimetric accuracy of a trajectory based delivery technique in which an optimized radiation beam is delivered along a Couch-Gantry trajectory that is formed by simultaneous rotation of the linac gantry and the treatment couch. Methods: Nine trajectory based cranial SRS treatment plans were created using in-house optimization software. The plans were calculated for delivery on the TrueBeam STx linac with 6MV photon beam. Dose optimization was performed along a user-defined trajectory using MLC modulation, dose rate modulation and jaw tracking. The pre-defined trajectory chosen for this study is formed by a couch rotation through its full range of 180 degrees while the gantry makes four partial arc sweeps which are 170 degrees each. For final dose calculation, the trajectory based plans were exported to the Varian Eclipse Treatment Planning System. The plans were calculated on a homogeneous cube phantom measuring 18.2×18.2×18.2 cm3 with the analytical anisotropic algorithm (AAA) using a 1mm3 calculation voxel. The plans were delivered on the TrueBeam linac via the developer’s mode. Point dose measurements were performed on 9 patients with the IBA CC01 mini-chamber with a sensitive volume of 0.01 cc. Gafchromic film measurements along the sagittal and coronal planes were performed on three of the 9 treatment plans. Point dose values were compared with ion chamber measurements. Gamma analysis comparing film measurement and AAA calculations was performed using FilmQA Pro. Results: The AAA calculations and measurements were in good agreement. The point dose difference between AAA and ion chamber measurements were within 2.2%. Gamma analysis test pass rates (2%, 2mm passing criteria) for the Gafchromic film measurements were >95%. Conclusion: We have successfully tested TrueBeam’s ability to deliver accurate trajectory based treatments involving simultaneous gantry and couch rotation with MLC and dose rate modulation along the

  20. SU-F-BRE-10: Methods to Simulate and Measure the Attenuation for Modeling a Couch Top with Rails for FFF Treatment Delivery On the Varian Edge Linac

    International Nuclear Information System (INIS)

    Gulam, M; Gardner, S; Zhao, B; Snyder, K; Song, K; Li, H; Gordon, J; Wen, N; Chetty, I; Kearns, W

    2014-01-01

    Purpose: To measure attenuation for modelling of the KVue Couchtop for 6X and 10X FFF SRS/SBRT treatment Methods: Treatment planning simulation studies were done using 6X FFF beams to estimate the dosimetric impact of KVue couchtops (including the Q-Fix IGRT [carbon fiber] and Calypso [nonconductive Kevlar material]) with a structure model obtained from a research workstation (Eclipse, advanced planning interface (API) v13). Prior to installation on the Varian Edge linac, the couchtop along with (Kevlar) rails were CT scanned with the rails at various positions. An additional scan with the couchtop 15cm above the CT table top was obtained with 20cm solid water to facilitate precised/indexed data acquisition. Measurements for attenuation were obtained for field sizes of 2, 4 and 10 cm 2 at 42 gantry angles including 6 pairs of opposing fields and other angles for oblique delivery where the beams traversed the couchtop and or rails. The delivery was fully automated with xml scripts running in developer mode. The results were then used to determine an accurate structure model for AAA (Eclipse v11) planning of IMRT and RapidArc delivery. Results: The planning simulation relative dose attenuation for oblique entry was not significantly different than the Exact IGRT or BrainLab iBeam couch except that the rails added 6% additional attenuation. The relative attenuation measurements for PA, PA (rails: inner position), oblique, oblique (rails: outer position), oblique (rails: inner position) were: −2.0%, −2.5%, −15.6%, −2.5%, −5.0% for 6X FFF and −1.4%, −1.5%, −12.2%, − 2.5%, −5.0% for 10X FFF with slight decrease in attenuation versus field size. A Couch structure model (with HU values) was developed. Calculation compared to measurement showed good agreement except for oblique (rails: outer position) where differences approached a magnitude of 6%. Conclusion: A model of the couch structures has been developed accounting for attenuation for FFF beams

  1. Medical Cyclotrons

    Science.gov (United States)

    Friesel, D. L.; Antaya, T. A.

    Particle accelerators were initially developed to address specific scientific research goals, yet they were used for practical applications, particularly medical applications, within a few years of their invention. The cyclotron's potential for producing beams for cancer therapy and medical radioisotope production was realized with the early Lawrence cyclotrons and has continued with their more technically advanced successors — synchrocyclotrons, sector-focused cyclotrons and superconducting cyclotrons. While a variety of other accelerator technologies were developed to achieve today's high energy particles, this article will chronicle the development of one type of accelerator — the cyclotron, and its medical applications. These medical and industrial applications eventually led to the commercial manufacture of both small and large cyclotrons and facilities specifically designed for applications other than scientific research.

  2. A Low-Power CMOS Piezoelectric Transducer Based Energy Harvesting Circuit for Wearable Sensors for Medical Applications

    Directory of Open Access Journals (Sweden)

    Taeho Oh

    2017-12-01

    Full Text Available Piezoelectric vibration based energy harvesting systems have been widely utilized and researched as powering modules for various types of sensor systems due to their ease of integration and relatively high energy density compared to RF, thermal, and electrostatic based energy harvesting systems. In this paper, a low-power CMOS full-bridge rectifier is presented as a potential solution for an efficient energy harvesting system for piezoelectric transducers. The energy harvesting circuit consists of two n-channel MOSFETs (NMOS and two p-channel MOSFETs (PMOS devices implementing a full-bridge rectifier coupled with a switch control circuit based on a PMOS device driven by a comparator. With a load of 45 kΩ, the output rectifier voltage and the input piezoelectric transducer voltage are 694 mV and 703 mV, respectably, while the VOUT versus VIN conversion ratio is 98.7% with a PCE of 52.2%. The energy harvesting circuit has been designed using 130 nm standard CMOS process.

  3. Energy and nutritional value of diets used in patients alimentation and their assessment by patients of selected clinical department in the Military Medical Institute in Warsaw.

    Science.gov (United States)

    Kłos, Krzysztof; Bertrandt, Jerzy; Jałocha, Lukasz; Matuszewski, Tomasz; Abramowicz, Michał

    2007-01-01

    The aim of the work was laboratory assessment of energy and nutritional value of general and light diets used in patients of selected clinical department in the Military Medical Institute in Warsaw alimentation. Using questionnaire method the assessment of diets was done by patients too. Meals given to patients in hospital not always fulfilled nutritional requirements. Additional consumption of supplementary products did not always meet the requirements of proper nutrition. Half of examined patients appraised nutrition variety as good but at the same time claimed the there was not enough fruits and vegetables.

  4. Occupational radiation protection around medical linear accelerators: measurements and semi-analytical approaches

    International Nuclear Information System (INIS)

    Donadille, L.; Derreumaux, S.; Mantione, J.; Robbes, I.; Trompier, F.; Amgarou, K.; Asselineau, B.; Martin, A.

    2008-01-01

    Full text: X-rays produced by high-energy (larger than 6 MeV) medical electron linear accelerators create secondary neutron radiation fields mainly by photonuclear reactions inside the materials of the accelerator head, the patient and the walls of the therapy room. Numerous papers were devoted to the study of neutron production in medical linear accelerators and resulting decay of activation products. However, data associated to doses delivered to workers in treatment conditions are scarce. In France, there are more than 350 external radiotherapy facilities representing almost all types of techniques and designs. IRSN carried out a measurement campaign in order to investigate the variation of the occupational dose according the different encountered situations. Six installations were investigated, associated with the main manufacturers (Varian, Elekta, General Electrics, Siemens), for several nominal energies, conventional and IMRT techniques, and bunker designs. Measurements were carried out separately for neutron and photon radiation fields, and for radiation associated with the decay of the activation products, by means of radiometers, tissue-equivalent proportional counters and spectrometers (neutron and photon spectrometry). They were performed at the positions occupied by the workers, i.e. outside the bunker during treatments, inside between treatments. Measurements have been compared to published data. In addition, semi-empirical analytical approaches recommended by international protocols were used to estimate doses inside and outside the bunkers. The results obtained by both approaches were compared and analysed. The annual occupational effective dose was estimated to about 1 mSv, including more than 50 % associated with the decay of activation products and less than 10 % due to direct exposure to leakage neutrons produced during treatments. (author)

  5. SU-E-J-47: Comparison of Online Image Registrations of Varian TrueBeam Cone-Beam CT and BrainLab ExacTrac Imaging Systems

    International Nuclear Information System (INIS)

    Li, J; Shi, W; Andrews, D; Werner-Wasik, M; Yu, Y; Liu, H

    2015-01-01

    Purpose To compare online image registrations of TrueBeam cone-beam CT (CBCT) and BrainLab ExacTrac imaging systems. Methods Tests were performed on a Varian TrueBeam STx linear accelerator (Version 2.0), which is integrated with a BrainLab ExacTrac imaging system (Version 6.0.5). The study was focused on comparing the online image registrations for translational shifts. A Rando head phantom was placed on treatment couch and immobilized with a BrainLab mask. The phantom was shifted by moving the couch translationally for 8 mm with a step size of 1 mm, in vertical, longitudinal, and lateral directions, respectively. At each location, the phantom was imaged with CBCT and ExacTrac x-ray. CBCT images were registered with TrueBeam and ExacTrac online registration algorithms, respectively. And ExacTrac x-ray image registrations were performed. Shifts calculated from different registrations were compared with nominal couch shifts. Results The averages and ranges of absolute differences between couch shifts and calculated phantom shifts obtained from ExacTrac x-ray registration, ExacTrac CBCT registration with default window, ExaxTrac CBCT registration with adjusted window (bone), Truebeam CBCT registration with bone window, and Truebeam CBCT registration with soft tissue window, were: 0.07 (0.02–0.14), 0.14 (0.01–0.35), 0.12 (0.02–0.28), 0.09 (0–0.20), and 0.06 (0–0.10) mm, in vertical direction; 0.06 (0.01–0.12), 0.27 (0.07–0.57), 0.23 (0.02–0.48), 0.04 (0–0.10), and 0.08 (0– 0.20) mm, in longitudinal direction; 0.05 (0.01–0.21), 0.35 (0.14–0.80), 0.25 (0.01–0.56), 0.19 (0–0.40), and 0.20 (0–0.40) mm, in lateral direction. Conclusion The shifts calculated from ExacTrac x-ray and TrueBeam CBCT registrations were close to each other (the differences between were less than 0.40 mm in any direction), and had better agreements with couch shifts than those from ExacTrac CBCT registrations. There were no significant differences between True

  6. Feasibility Study for a Two-Energy Compact Medical Cyclotron Controlled by Two Pairs of Main Coils

    International Nuclear Information System (INIS)

    Blum, D.; Breckow, J.; Zink, K.

    2013-01-01

    At Paul Scherrer Institute, Villigen, Switzerland, protons are accelerated for the proton therapy by a 250 MeV isochronous cyclotron. As for radiotherapy less energy is required (about 70 MeV) a carbon degrader reduces the extracted beam energy. This involves the increase of emittance, decrease of transmission, more activated components and a higher dose for the staff. By extracting a lower energy beam from the cyclotron, less degrade would be necessary and the above mentioned side-effects could be minimized. A possible solution could be to extract two energies from the cyclotron, 250 MeV for very deep located tumours and 230-235 MeV for others. A technically easy and affordable solution for this problem might be a two-energy cyclotron controlled by just two pairs of main coils. The feasibility of this solution has been analysed in this study. The compounded magnetic flux density B is the sum of the coil's and the iron's flux density. The amount caused by a coil is mainly responsible for the shape of the compounded flux density. Therefore a split of the coil pair was simulated to obtain more possibilities in the adjustment of a lower-energy beam to its ideal isochronous shape. The result is a simulated isochronous 240 MeV beam which was found with an tangential split of the coil pair, their repositioning and the increasing of current in the first coil pair and decreasing in the other one. The tangential split seemed to reduce the problem of the irons linear share of B. This feasibility study is seen as a first step before using 3D-capable software which considers a higher spatial resolution and the influence of temperature.(author)

  7. Dual-energy CT-cholangiography in potential donors for living-related liver transplantation: Improved biliary visualization by intravenous morphine co-medication

    International Nuclear Information System (INIS)

    Sommer, C.M.; Schwarzwaelder, C.B.; Stiller, W.; Schindera, S.T.; Heye, T.; Stampfl, U.; Bellemann, N.; Holzschuh, M.; Schmidt, J.; Weitz, J.; Grenacher, L.; Kauczor, H.U.; Radeleff, B.A.

    2012-01-01

    Purpose: To prospectively evaluate whether intravenous morphine co-medication improves bile duct visualization of dual-energy CT-cholangiography. Materials and methods: Forty potential donors for living-related liver transplantation underwent CT-cholangiography with infusion of a hepatobiliary contrast agent over 40 min. Twenty minutes after the beginning of the contrast agent infusion, either normal saline (n = 20 patients; control group [CG]) or morphine sulfate (n = 20 patients; morphine group [MG]) was injected. Forty-five minutes after initiation of the contrast agent, a dual-energy CT acquisition of the liver was performed. Applying dual-energy post-processing, pure iodine images were generated. Primary study goals were determination of bile duct diameters and visualization scores (on a scale of 0 to 3: 0—not visualized; 3—excellent visualization). Results: Bile duct visualization scores for second-order and third-order branch ducts were significantly higher in the MG compared to the CG (2.9 ± 0.1 versus 2.6 ± 0.2 [P < 0.001] and 2.7 ± 0.3 versus 2.1 ± 0.6 [P < 0.01], respectively). Bile duct diameters for the common duct and main ducts were significantly higher in the MG compared to the CG (5.9 ± 1.3 mm versus 4.9 ± 1.3 mm [P < 0.05] and 3.7 ± 1.3 mm versus 2.6 ± 0.5 mm [P < 0.01], respectively). Conclusion: Intravenous morphine co-medication significantly improved biliary visualization on dual-energy CT-cholangiography in potential donors for living-related liver transplantation

  8. Dual-energy CT-cholangiography in potential donors for living-related liver transplantation: Improved biliary visualization by intravenous morphine co-medication

    Energy Technology Data Exchange (ETDEWEB)

    Sommer, C.M., E-mail: christof.sommer@med.uni-heidelberg.de [Department of Diagnostic and Interventional Radiology, University Hospital Heidelberg, Heidelberg (Germany); Schwarzwaelder, C.B.; Stiller, W. [Department of Diagnostic and Interventional Radiology, University Hospital Heidelberg, Heidelberg (Germany); Schindera, S.T. [Department of Diagnostic, Interventional, and Pediatric Radiology, University Hospital and University of Berne, Berne (Switzerland); Heye, T.; Stampfl, U.; Bellemann, N.; Holzschuh, M. [Department of Diagnostic and Interventional Radiology, University Hospital Heidelberg, Heidelberg (Germany); Schmidt, J.; Weitz, J. [Department of General, Abdominal and Transplantation Surgery, University Hospital Heidelberg, Heidelberg (Germany); Grenacher, L.; Kauczor, H.U.; Radeleff, B.A. [Department of Diagnostic and Interventional Radiology, University Hospital Heidelberg, Heidelberg (Germany)

    2012-09-15

    Purpose: To prospectively evaluate whether intravenous morphine co-medication improves bile duct visualization of dual-energy CT-cholangiography. Materials and methods: Forty potential donors for living-related liver transplantation underwent CT-cholangiography with infusion of a hepatobiliary contrast agent over 40 min. Twenty minutes after the beginning of the contrast agent infusion, either normal saline (n = 20 patients; control group [CG]) or morphine sulfate (n = 20 patients; morphine group [MG]) was injected. Forty-five minutes after initiation of the contrast agent, a dual-energy CT acquisition of the liver was performed. Applying dual-energy post-processing, pure iodine images were generated. Primary study goals were determination of bile duct diameters and visualization scores (on a scale of 0 to 3: 0—not visualized; 3—excellent visualization). Results: Bile duct visualization scores for second-order and third-order branch ducts were significantly higher in the MG compared to the CG (2.9 ± 0.1 versus 2.6 ± 0.2 [P < 0.001] and 2.7 ± 0.3 versus 2.1 ± 0.6 [P < 0.01], respectively). Bile duct diameters for the common duct and main ducts were significantly higher in the MG compared to the CG (5.9 ± 1.3 mm versus 4.9 ± 1.3 mm [P < 0.05] and 3.7 ± 1.3 mm versus 2.6 ± 0.5 mm [P < 0.01], respectively). Conclusion: Intravenous morphine co-medication significantly improved biliary visualization on dual-energy CT-cholangiography in potential donors for living-related liver transplantation.

  9. Distance walked and run as improved metrics over time-based energy estimation in epidemiological studies and prevention; evidence from medication use.

    Directory of Open Access Journals (Sweden)

    Paul T Williams

    Full Text Available The guideline physical activity levels are prescribed in terms of time, frequency, and intensity (e.g., 30 minutes brisk walking, five days a week or its energy equivalence and assume that different activities may be combined to meet targeted goals (exchangeability premise. Habitual runners and walkers may quantify exercise in terms of distance (km/day, and for them, the relationship between activity dose and health benefits may be better assessed in terms of distance rather than time. Analyses were therefore performed to test: 1 whether time-based or distance-based estimates of energy expenditure provide the best metric for relating running and walking to hypertensive, high cholesterol, and diabetes medication use (conditions known to be diminished by exercise, and 2 the exchangeability premise.Logistic regression analyses of medication use (dependent variable vs. metabolic equivalent hours per day (METhr/d of running, walking and other exercise (independent variables using cross-sectional data from the National Runners' (17,201 male, 16,173 female and Walkers' Health Studies (3,434 male, 12,384 female.Estimated METhr/d of running and walking activity were 38% and 31% greater, respectively, when calculated from self-reported time than distance in men, and 43% and 37% greater in women, respectively. Percent reductions in the odds for hypertension and high cholesterol medication use per METhr/d run or per METhr/d walked were ≥ 2-fold greater when estimated from reported distance (km/wk than from time (hr/wk. The per METhr/d odds reduction was significantly greater for the distance- than the time-based estimate for hypertension (runners: P<10(-5 for males and P=0.003 for females; walkers: P=0.03 for males and P<10(-4 for females, high cholesterol medication use in runners (P<10(-4 for males and P=0.02 for females and male walkers (P=0.01 for males and P=0.08 for females and for diabetes medication use in male runners (P<10(-3.Although causality

  10. R&D on scintillation materials for novel ionizing radiation detectors for High Energy Physics, medical imaging and industrial applications

    CERN Multimedia

    Chipaux, R; Rinaldi, D; Boursier, Y M; Vasilyev, A; Tikhomirov, V; Morel, C; Choi, Y; Tamulaitis, G

    2002-01-01

    The Crystal Clear Collaboration (CCC) was approved by the Detector R&D Committee as RD18 in 1990 with the objective of developing new inorganic scintillators suitable for crystal electromagnetic calorimeters of LHC experiments. From 1990 to 1994, CCC made an intensive investigation for the quest of the most adequate ideal scintillator for the LHC; three main candidates were identified and extensively studied : CeF$_{3}$, PbWO$_{4}$ and heavy scintillating glasses. Lead tungstate was chosen by CMS and ALICE as the most cost effective crystal compliant to LHC conditions. Today 76648 PWO crystals are installed in CMS and 17920 in ALICE. After this success Crystal clear has continued its investigation on new scintillators and the understanding of scintillation mechanisms and light transfer properties in particular : The understanding of cerium ion as activator, The development of LuAP, LuYAP crystals for medical imaging applications, (CERN patent) Investigation of Ytterbium based scintillators for solar ne...

  11. Studying the molecular mechanisms of radiation damage : low-energy electron interactions with biomolecules and medically relevant molecules

    International Nuclear Information System (INIS)

    Tanzer, K.

    2015-01-01

    Since it was discovered in the year 2000 that secondary electrons with energies below 20 eV, which are the most abundant secondary species produced upon the interaction of ionizing radiation with biological tissue, can induce severe damages in the DNA such as single and double strand breaks, the interest for the study of the interaction of electrons with essential molecules of the human body has grown immensely. Double strand breaks can lead to cancer and are therefore a substantial threat to human health, however, the radiation research community is not sure how these strand breaks are formed upon interaction with ionizing radiation. The fact that even electrons with energies well below the ionization threshold can induce great damage in biological molecules via a resonant process called dissociative electron attachment (DEA), has even furthered the interest in these electron interactions, as it was shown to be a very efficient decomposition mechanism. A variety of studies, such as DEA studies to components of the DNA, for example, have been undertaken so far to shed more light on the role electrons play in the radiation damage of biomolecules. In this thesis two nucleobases, adenine and hypoxanthine, have been studied by observing their response towards low-energy electrons. It has been found that these nucleobases behave in a similar manner upon low-energy electron interaction, as do other nucleobases, that have been studied previously. The loss of hydrogen is suspected to act as a precursor for the decomposition of the DNA and the nucleobases can also undergo ring cleavage, which will induce substantial damage in the DNA. Furthermore, the search for improved and more efficient methods for the treatment of cancer is as important as ever, considering the ever-rising number of cancer deaths. Radiotherapy has proven to be one of the best treatments for tumors, but was found to be ineffective in hypoxic - oxygen deprived - tumors. Compounds called radiosensitizers

  12. Validity of mid arm circumference to detect protein energy malnutrition among 8-11 months old infants in a rural medical college of West Bengal.

    Science.gov (United States)

    Sadhukhan, Sanjoy Kr; Chatterjee, Chitra; Shrivastava, Prabha; Sardar, Jadav Chandra; Joardar, Gautam Kr; Lahiri, Saibendu

    2010-09-01

    This institution-based cross-sectional observational validation study was conducted in the immunisation clinic of North Bengal Medical College and Hospital, Sushrutanagar. The objective was to identify the validity characteristics of mid arm circumference to detect protein energy malnutrition among 8-11 months infants and to find out a suitable cut-off value if any. Study variables were age, sex, body weight and mid arm circumference. Mid arm circumference was validated against weight for age criteria (gold standard) of malnutrition. The mean mid arm circumference of the infants was found to be almost constant with only about 2.22% change over 4 months, signifying that single cut-off point can be used to detect protein energy malnutrition. Mid arm circumference values from 13.0 to 12.5 cm were found to have the highest accuracy to detect protein energy malnutrition (about 86%). The cut-off values of 12.5 and 12.6 cm were noted to have a sensitivity and specificity of about 52% and 96% respectively, a false negativity of 48% but a false positivity of only 4%. Receiver operating characteristics curve detected 12.5(12.6) cm as the best diagnostic cut-off point which can detect more than 50% of the malnourished babies with very little false positivity/misdiagnosis (only 4%). A simple measuring tape with some reorientation of the health workers can detect the beginning of childhood malnutrition.

  13. Deconstructing medical practice marketing.

    Science.gov (United States)

    Kasbo, Abe

    2010-01-01

    The healthcare marketing game has radically changed. Medical practices must rely on strategies instead of tactics to better separate themselves from the competition. The Internet has become a disruptive force in marketing, tipping the balance and control of the reputations of medical practices to the patient. Done right, medical practices can harness this new energy to attract new patients and keep current patients loyal.

  14. An MCNP-based model for the evaluation of the photoneutron dose in high energy medical electron accelerators.

    Science.gov (United States)

    Carinou, Eleutheria; Stamatelatos, Ion Evangelos; Kamenopoulou, Vassiliki; Georgolopoulou, Paraskevi; Sandilos, Panayotis

    The development of a computational model for the treatment head of a medical electron accelerator (Elekta/Philips SL-18) by the Monte Carlo code mcnp-4C2 is discussed. The model includes the major components of the accelerator head and a pmma phantom representing the patient body. Calculations were performed for a 14 MeV electron beam impinging on the accelerator target and a 10 cmx10 cm beam area at the isocentre. The model was used in order to predict the neutron ambient dose equivalent at the isocentre level and moreover the neutron absorbed dose distribution within the phantom. Calculations were validated against experimental measurements performed by gold foil activation detectors. The results of this study indicated that the equivalent dose at tissues or organs adjacent to the treatment field due to photoneutrons could be up to 10% of the total peripheral dose, for the specific accelerator characteristics examined. Therefore, photoneutrons should be taken into account when accurate dose calculations are required to sensitive tissues that are adjacent to the therapeutic X-ray beam. The method described can be extended to other accelerators and collimation configurations as well, upon specification of treatment head component dimensions, composition and nominal accelerating potential.

  15. The role of industrial-sanitary laboratory of medical aid station of Federal administration in prophylaxis of emergency situations at the plants of nuclear-energy complex and liquidation of their after-effects

    International Nuclear Information System (INIS)

    Antipin, E.B.

    1995-01-01

    On the example of several radiation accidents the author summarized the personal practical experience in organization of work in industrial-sanitary laboratories based at the nuclear energy plants of nuclear-energy complex, in respect of prophylaxis of emergency radiation situations and liquidation of their after-effects. It is pointed out that successful activity in rendering emergency medical aid in emergency situations, caused by radiation accidents, is possible only subject to close contact of science, practical medical care and sanitary service which should become a part of the uniform public health system. 4 refs

  16. 10 CFR 55.21 - Medical examination.

    Science.gov (United States)

    2010-01-01

    ... 10 Energy 2 2010-01-01 2010-01-01 false Medical examination. 55.21 Section 55.21 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) OPERATORS' LICENSES Medical Requirements § 55.21 Medical examination. An applicant for a license shall have a medical examination by a physician. A licensee shall have a medical...

  17. Public Health Ministere stablish that all medical equipment records request who emit ionizing radiations providing health organizations, Public or privates, such as enterprise who trade medical products, have to be carry out between of the Public a Health Ministere Technology Department and DINATEN of the Industry energy and Mining Ministere

    International Nuclear Information System (INIS)

    2004-01-01

    The present decree stablish that the evaluation of all the applications of registration of medical teams that emit ionizing radiations, coming from the institutions of health, you publish or private, as well as companies that market medical products will be carried out among the Department of Technology it Prescribes of the Ministry of Health it Public and the DINATEN of the Ministry of Industry Energy and Mining

  18. Optical and energy dependent response of the alanine gel solution produced at IPEN to clinical photons and electrons beams

    International Nuclear Information System (INIS)

    Silva, Cleber F.

    2011-01-01

    The DL-Alanine (C 3 H 7 NO 2 ) is an amino acid tissue equivalent traditionally used as standard dosimetric material in EPR dosimetry. Recently, it has been studied to be applied in gel dosimetry, considering that the addition of Alanine in the Fricke gel solution improves the production of ferric ions radiation induced. The spectrophotometric evaluation technique can be used comparing the two spectrum wavelengths bands: 457 nm band that corresponds to ferrous ions and 588 nm band that corresponds to ferric ions concentration to evaluate the dosimetric properties of this material. The performance of the Alanine gel solution developed at IPEN has been firstly studied using the spectrophotometric technique aiming to apply this material to 3D clinical doses evaluations using MRI technique. In this work, the optical and the energy dependent response of this solution submitted to clinical photons and electrons beams were studied. Different batches of gel solutions were prepared and maintained at low temperature during 12 h to solidification. Before irradiation, the samples were maintained during 1 h at room temperature. The photons and electrons irradiations were carried out using a Varian 2100C Medical Linear Accelerator of the Radiotherapy Department of the Hospital das Clinicas of the University of Sao Paulo with absorbed doses between 1 and 40 Gy; radiation field of 10 x 10 cm 2 ; photon energies of 6 MeV and 15 MeV; and electron with energies between 6 and 15 MeV. The obtained results indicate that signal response dependence for clinical photons and electrons beams, to the same doses, for Alanine gel dosimeter is better than 3.6 % (1σ), and the energy dependence response, to the same doses, is better 3% (1σ) for both beams. These results indicate that the same calibration factor can be used and the optical response is energy independent in the studied dose range and clinical photons and electrons beams energies. (author)

  19. Uncertainties in the correction factors as the dose polarization and recombination at different energies

    International Nuclear Information System (INIS)

    Alejo Luque, L.; Rodriguez Romero, R.; Castro Tejero, P.; Fandino Lareo, J. M.

    2011-01-01

    This paper discusses the measures and uncertainties of the correction factors for dose-polarization (k, 1) and recombination (k,) of different ionization chambers plane-parallel and cylindrical. The values ??have been obtained using photon and electron beams of various energies generated by linear accelerators nominal Varian 21EX CLJNAC Tomotherapy Hi-Art and JI. We study the cases in which you can avoid the application of the factors obtained, according to the criteria proposed

  20. WE-H-202-04: Advanced Medical Image Registration Techniques

    International Nuclear Information System (INIS)

    Christensen, G.

    2016-01-01

    Deformable image registration has now been commercially available for several years, with solid performance in a number of sites and for several applications including contour and dose mapping. However, more complex applications have arisen, such as assessing response to radiation therapy over time, registering images pre- and post-surgery, and auto-segmentation from atlases. These applications require innovative registration algorithms to achieve accurate alignment. The goal of this session is to highlight emerging registration technology and these new applications. The state of the art in image registration will be presented from an engineering perspective. Translational clinical applications will also be discussed to tie these new registration approaches together with imaging and radiation therapy applications in specific diseases such as cervical and lung cancers. Learning Objectives: To understand developing techniques and algorithms in deformable image registration that are likely to translate into clinical tools in the near future. To understand emerging imaging and radiation therapy clinical applications that require such new registration algorithms. Research supported in part by the National Institutes of Health under award numbers P01CA059827, R01CA166119, and R01CA166703. Disclosures: Phillips Medical systems (Hugo), Roger Koch (Christensen) support, Varian Medical Systems (Brock), licensing agreements from Raysearch (Brock) and Varian (Hugo).; K. Brock, Licensing Agreement - RaySearch Laboratories. Research Funding - Varian Medical Systems; G. Hugo, Research grant from National Institutes of Health, award number R01CA166119.; G. Christensen, Research support from NIH grants CA166119 and CA166703 and a gift from Roger Koch. There are no conflicts of interest.

  1. WE-H-202-04: Advanced Medical Image Registration Techniques

    Energy Technology Data Exchange (ETDEWEB)

    Christensen, G. [University of Iowa (United States)

    2016-06-15

    Deformable image registration has now been commercially available for several years, with solid performance in a number of sites and for several applications including contour and dose mapping. However, more complex applications have arisen, such as assessing response to radiation therapy over time, registering images pre- and post-surgery, and auto-segmentation from atlases. These applications require innovative registration algorithms to achieve accurate alignment. The goal of this session is to highlight emerging registration technology and these new applications. The state of the art in image registration will be presented from an engineering perspective. Translational clinical applications will also be discussed to tie these new registration approaches together with imaging and radiation therapy applications in specific diseases such as cervical and lung cancers. Learning Objectives: To understand developing techniques and algorithms in deformable image registration that are likely to translate into clinical tools in the near future. To understand emerging imaging and radiation therapy clinical applications that require such new registration algorithms. Research supported in part by the National Institutes of Health under award numbers P01CA059827, R01CA166119, and R01CA166703. Disclosures: Phillips Medical systems (Hugo), Roger Koch (Christensen) support, Varian Medical Systems (Brock), licensing agreements from Raysearch (Brock) and Varian (Hugo).; K. Brock, Licensing Agreement - RaySearch Laboratories. Research Funding - Varian Medical Systems; G. Hugo, Research grant from National Institutes of Health, award number R01CA166119.; G. Christensen, Research support from NIH grants CA166119 and CA166703 and a gift from Roger Koch. There are no conflicts of interest.

  2. Clean energy : nuclear energy world

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2007-10-15

    This book explains the nuclear engineering to kids with easy way. There are explanations of birth of nuclear energy such as discover of nuclear and application of modern technology of nuclear energy, principles and structure of nuclear power plant, fuel, nuclear waste management, use of radiation for medical treatment, food supplies, industry, utilization of neutron. It indicates the future of nuclear energy as integral nuclear energy and nuclear fusion energy.

  3. Medical cyclotron facilities

    International Nuclear Information System (INIS)

    1984-09-01

    This report examines the separate proposals from the Austin Hospital and the Australian Atomic Energy Commission for a medical cyclotron facility. The proponents have argued that a cyclotron facility would benefit Australia in areas of patient care, availability and export of radioisotopes, and medical research. Positron emission tomography (PET) and neutron beam therapy are also examined

  4. Commissioning and early experience with a new-generation low-energy linear accelerator with advanced delivery and imaging functionalities

    Directory of Open Access Journals (Sweden)

    Fogliata Antonella

    2011-09-01

    Full Text Available Abstract Background A new-generation low-energy linear accelerator (UNIQUE was introduced in the clinical arena during 2009 by Varian Medical Systems. The world's first UNIQUE was installed at Oncology Institute of Southern Switzerland and put into clinical operation in June 2010. The aim of the present contribution was to report experience about its commissioning and first year results from clinical operation. Methods Commissioning data, beam characteristics and the modeling into the treatment planning system were summarized. Imaging system of UNIQUE included a 2D-2D matching capability and tests were performed to identify system repositioning capability. Finally, since the system is capable of delivering volumetric modulated arc therapy with RapidArc, a summary of the tests performed for such modality to assess its performance in preclinical settings and during clinical usage was included. Results Isocenter virtual diameter was measured as less than 0.2 mm. Observed accuracy of isocenter determination and repositioning for 2D-2D matching procedures in image guidance was Conclusions The results of the commissioning tests and of the first period of clinical operation, resulted meeting specifications and having good margins respect to tolerances. UNIQUE was put into operation for all delivery techniques; in particular, as shown by the pre-treatment quality assurance results, it enabled accurate and safe delivery of RapidArc plans.

  5. Calibration of PADC-based neutron area dosemeters in the neutron field produced in the treatment room of a medical LINAC

    International Nuclear Information System (INIS)

    Bedogni, R.; Domingo, C.; Esposito, A.; Gentile, A.; García-Fusté, M.J.; San-Pedro, M. de; Tana, L.; D’Errico, F.; Ciolini, R.; Di Fulvio, A.

    2013-01-01

    PADC-based nuclear track detectors have been widely used as convenient ambient dosemeters in many working places. However, due to the large energy dependence of their response in terms of ambient dose equivalent (H ∗ (10)) and to the diversity of workplace fields in terms of energy distribution, the appropriate calibration of these dosemeters is a delicate task. These are among the reasons why ISO has introduced the 12789 Series of Standards, where the simulated workplace neutron fields are introduced and their use to calibrate neutron dosemeters is recommended. This approach was applied in the present work to the UAB PADC-based nuclear track detectors. As a suitable workplace, the treatment room of a 15 MV Varian CLINAC DHX medical accelerator, located in the Ospedale S. Chiara (Pisa), was chosen. Here the neutron spectra in two points of tests (1.5 m and 2 m from the isocenter) were determined with the INFN-LNF Bonner Sphere Spectrometer equipped with Dysprosium activation foils (Dy-BSS), and the values of H ∗ (10) were derived on this basis. The PADC dosemeters were exposed in these points. Their workplace specific H*(10) responses were determined and compared with those previously obtained in different simulated workplace or reference (ISO 8529) neutron fields. - Highlights: ► The neutron field of a medical LINAC was used to calibrate PADC neutron dosemeters. ► The neutron spectra were derived with a Dy-foil based Bonner Sphere Spectrometer. ► Workplace specific calibration factor were derived for the PADC dosemeters. ► These factors were compared with those obtained in reference neutron fields

  6. SU-E-J-13: Six Degree of Freedom Image Fusion Accuracy for Cranial Target Localization On the Varian Edge Stereotactic Radiosurgery System: Comparison Between 2D/3D and KV CBCT Image Registration

    Energy Technology Data Exchange (ETDEWEB)

    Xu, H [Wayne State University, Detroit, MI (United States); Song, K; Chetty, I; Kim, J [Henry Ford Health System, Detroit, MI (United States); Wen, N [Henry Ford Health System, West Bloomfield, MI (United States)

    2015-06-15

    Purpose: To determine the 6 degree of freedom systematic deviations between 2D/3D and CBCT image registration with various imaging setups and fusion algorithms on the Varian Edge Linac. Methods: An anthropomorphic head phantom with radio opaque targets embedded was scanned with CT slice thicknesses of 0.8, 1, 2, and 3mm. The 6 DOF systematic errors were assessed by comparing 2D/3D (kV/MV with CT) with 3D/3D (CBCT with CT) image registrations with different offset positions, similarity measures, image filters, and CBCT slice thicknesses (1 and 2 mm). The 2D/3D registration accuracy of 51 fractions for 26 cranial SRS patients was also evaluated by analyzing 2D/3D pre-treatment verification taken after 3D/3D image registrations. Results: The systematic deviations of 2D/3D image registration using kV- kV, MV-kV and MV-MV image pairs were within ±0.3mm and ±0.3° for translations and rotations with 95% confidence interval (CI) for a reference CT with 0.8 mm slice thickness. No significant difference (P>0.05) on target localization was observed between 0.8mm, 1mm, and 2mm CT slice thicknesses with CBCT slice thicknesses of 1mm and 2mm. With 3mm CT slice thickness, both 2D/3D and 3D/3D registrations performed less accurately in longitudinal direction than thinner CT slice thickness (0.60±0.12mm and 0.63±0.07mm off, respectively). Using content filter and using similarity measure of pattern intensity instead of mutual information, improved the 2D/3D registration accuracy significantly (P=0.02 and P=0.01, respectively). For the patient study, means and standard deviations of residual errors were 0.09±0.32mm, −0.22±0.51mm and −0.07±0.32mm in VRT, LNG and LAT directions, respectively, and 0.12°±0.46°, −0.12°±0.39° and 0.06°±0.28° in RTN, PITCH, and ROLL directions, respectively. 95% CI of translational and rotational deviations were comparable to those in phantom study. Conclusion: 2D/3D image registration provided on the Varian Edge radiosurgery, 6 DOF

  7. SU-E-J-13: Six Degree of Freedom Image Fusion Accuracy for Cranial Target Localization On the Varian Edge Stereotactic Radiosurgery System: Comparison Between 2D/3D and KV CBCT Image Registration

    International Nuclear Information System (INIS)

    Xu, H; Song, K; Chetty, I; Kim, J; Wen, N

    2015-01-01

    Purpose: To determine the 6 degree of freedom systematic deviations between 2D/3D and CBCT image registration with various imaging setups and fusion algorithms on the Varian Edge Linac. Methods: An anthropomorphic head phantom with radio opaque targets embedded was scanned with CT slice thicknesses of 0.8, 1, 2, and 3mm. The 6 DOF systematic errors were assessed by comparing 2D/3D (kV/MV with CT) with 3D/3D (CBCT with CT) image registrations with different offset positions, similarity measures, image filters, and CBCT slice thicknesses (1 and 2 mm). The 2D/3D registration accuracy of 51 fractions for 26 cranial SRS patients was also evaluated by analyzing 2D/3D pre-treatment verification taken after 3D/3D image registrations. Results: The systematic deviations of 2D/3D image registration using kV- kV, MV-kV and MV-MV image pairs were within ±0.3mm and ±0.3° for translations and rotations with 95% confidence interval (CI) for a reference CT with 0.8 mm slice thickness. No significant difference (P>0.05) on target localization was observed between 0.8mm, 1mm, and 2mm CT slice thicknesses with CBCT slice thicknesses of 1mm and 2mm. With 3mm CT slice thickness, both 2D/3D and 3D/3D registrations performed less accurately in longitudinal direction than thinner CT slice thickness (0.60±0.12mm and 0.63±0.07mm off, respectively). Using content filter and using similarity measure of pattern intensity instead of mutual information, improved the 2D/3D registration accuracy significantly (P=0.02 and P=0.01, respectively). For the patient study, means and standard deviations of residual errors were 0.09±0.32mm, −0.22±0.51mm and −0.07±0.32mm in VRT, LNG and LAT directions, respectively, and 0.12°±0.46°, −0.12°±0.39° and 0.06°±0.28° in RTN, PITCH, and ROLL directions, respectively. 95% CI of translational and rotational deviations were comparable to those in phantom study. Conclusion: 2D/3D image registration provided on the Varian Edge radiosurgery, 6 DOF

  8. Energies; Energies

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2003-07-01

    In the framework of the National Debate on the energies in a context of a sustainable development some associations for the environment organized a debate on the nuclear interest facing the renewable energies. The first part presents the nuclear energy as a possible solution to fight against the greenhouse effect and the associated problem of the wastes management. The second part gives information on the solar energy and the possibilities of heat and electric power production. A presentation of the FEE (French wind power association) on the situation and the development of the wind power in France, is also provided. (A.L.B.)

  9. A Monte Carlo investigation of low-Z target image quality generated in a linear accelerator using Varian's VirtuaLinac

    International Nuclear Information System (INIS)

    Parsons, David; Robar, James L.; Sawkey, Daren

    2014-01-01

    Purpose: The focus of this work was the demonstration and validation of VirtuaLinac with clinical photon beams and to investigate the implementation of low-Z targets in a TrueBeam linear accelerator (Linac) using Monte Carlo modeling. Methods: VirtuaLinac, a cloud based web application utilizing Geant4 Monte Carlo code, was used to model the Linac treatment head components. Particles were propagated through the lower portion of the treatment head using BEAMnrc. Dose distributions and spectral distributions were calculated using DOSXYZnrc and BEAMdp, respectively. For validation, 6 MV flattened and flattening filter free (FFF) photon beams were generated and compared to measurement for square fields, 10 and 40 cm wide and at d max for diagonal profiles. Two low-Z targets were investigated: a 2.35 MeV carbon target and the proposed 2.50 MeV commercial imaging target for the TrueBeam platform. A 2.35 MeV carbon target was also simulated in a 2100EX Clinac using BEAMnrc. Contrast simulations were made by scoring the dose in the phosphor layer of an IDU20 aSi detector after propagating through a 4 or 20 cm thick phantom composed of water and ICRP bone. Results: Measured and modeled depth dose curves for 6 MV flattened and FFF beams agree within 1% for 98.3% of points at depths greater than 0.85 cm. Ninety three percent or greater of points analyzed for the diagonal profiles had a gamma value less than one for the criteria of 1.5 mm and 1.5%. The two low-Z target photon spectra produced in TrueBeam are harder than that from the carbon target in the Clinac. Percent dose at depth 10 cm is greater by 3.6% and 8.9%; the fraction of photons in the diagnostic energy range (25–150 keV) is lower by 10% and 28%; and contrasts are lower by factors of 1.1 and 1.4 (4 cm thick phantom) and 1.03 and 1.4 (20 cm thick phantom), for the TrueBeam 2.35 MV/carbon and commercial imaging beams, respectively. Conclusions: VirtuaLinac is a promising new tool for Monte Carlo modeling of novel

  10. Feasibility study of using PET to determine nitrogen concentration after high energy photon irradiation

    International Nuclear Information System (INIS)

    Alghamdi, A.A.; Spyrou, N.M.; Al-Mokhlef, J.; Alhaj, A.

    2007-01-01

    The technique of photon activation analysis (PAA) is widely employed in many fields as an effective non-invasive tool for measuring elemental compositions and concentrations. In recent years there has been a revival and growing interest of PAA in general and for medical applications in particular. The feasibility of using a PET scanner (Ecat Exact 931) to determine nitrogen concentration in a dead rabbit is described. This method is based on the photon activation of 14 N(γ,n) 13 N (T 1/2 = 9.9 min) using an 18 MV photon beam Medical Linear Accelerator (Varian 2300EX). (author)

  11. Nuclear energy and energy security

    International Nuclear Information System (INIS)

    Mamasakhlisi, J.

    2010-01-01

    Do Georgia needs nuclear energy? Nuclear energy is high technology and application of such technology needs definite level of industry, science and society development. Nuclear energy is not only source of electricity production - application of nuclear energy increases year-by-year for medical, science and industrial use. As an energy source Georgia has priority to extend hydro-power capacity by reasonable use of all available water resources. In parallel regime the application of energy efficiency and energy conservation measures should be considered but currently this is not prioritized by Government. Meanwhile this should be taken into consideration that attempts to reduce energy consumption by increasing energy efficiency would simply raise demand for energy in the economy as a whole. The Nuclear energy application needs routine calculation and investigation. For this reason Government Commission is already established. But it seems in advance that regional nuclear power plant for South-Caucasus region would be much more attractive for future

  12. Abortion - medical

    Science.gov (United States)

    Therapeutic medical abortion; Elective medical abortion; Induced abortion; Nonsurgical abortion ... A medical, or nonsurgical, abortion can be done within 7 weeks from the first day of the woman's last ...

  13. Ambient dose equivalent and personal points due to photoneutrons outside a facility that houses a linear accelerator of 18 MV varian; Equivalente de dosis ambiental y personal debida a fotoneutrones en puntos externos a una instalacion que alberga un acelerador lineal varian de 18 MV

    Energy Technology Data Exchange (ETDEWEB)

    Martinez, S. A.; Barquero, R.; Gomez-Ros, J. M.; Lallena, A. M.; Ponzano, P. E.

    2011-07-01

    The use of linear accelerators (linacs) with energies above 10 MV radiotherapy treatments RT and IMRT, can improve the distribution of the absorbed dose in the treated area, increasing the effectiveness of radiation treatments. However and as shown in the scientific literature, the production of photoneutrons for energies above 10 MeV can contribute to exposure of both patient and occupationally exposed workers and the public in the vicinity of the installation. It is therefore necessary to determine the value of ambient dose equivalent and staff both inside and outside the facilities that house these accelerators, especially for energies of 15 and 18 MV.

  14. Medical applications of cyclotrons

    International Nuclear Information System (INIS)

    Jean, R.; Fauchet, M.

    1978-01-01

    Isochronous cyclotrons used to accelerate different charged particles (protons, deuterons, alphas...) at variable energies, have important medical applications, for neutron teletherapy, in vivo or in vitro activation analysis or production of short-lived radioisotopes for nuclear medicine. The characteristics of the cyclotron presently available are described for these three applications (low energy 'compact' cyclotrons, cyclotrons of intermediate and high energies), and their advantages are discussed from the points of view of the medical requirements, the financial investments and the results obtained. (orig.) [de

  15. Energies; Energies

    Energy Technology Data Exchange (ETDEWEB)

    Cotard, E.

    2002-02-01

    A review is made about the consequences of the European directive on energy that entered into application in august 2000. It appears that most countries are opening their electricity and gas markets at a faster pace than required by the E.U. directive. European gas imports reached 480 Gm{sup 3} in 2000 and are expected to be over 700 Gm{sup 3} in 2015, so the question of the reliability of the gas suppliers has to be answered at the European level. The current time is marked by an increase of the complexity of the energy market that is due to different factors: 1) the delay in the implementation of European energy directives in France, 2) new arrangement is occurring in United-Kingdom in the energy sector, 3) the lack of a regulating authority in Germany, and 4) the difficulty of inter-connecting the different European energy networks. This transitory period may generate some economic imbalances and competition disturbances by allowing some enterprises to benefit from lower energy prices before others. (A.C.)

  16. Comparison of different strategies of use of on-board imagery (high energy [MV], low energy [kV], cone beam tomography) in radiotherapy; Comparaison des differentes strategies d'utilisation de l'imagerie embarquee (haute energie [MV], basse energie [kV], tomographie conique) en radiotherapie

    Energy Technology Data Exchange (ETDEWEB)

    Serre, A.A.; Marchesi, V.; Beckendorf, V.; Peiffert, D. [Service de radiotherapie, centre Alexis-Vautrin, Vandoeuvre-les-Nancy (France); Noel, A. [UMR 7039, centre de recherche en automatique de Nancy, Nancy universite, Vandoeuvre-les-Nancy (France); UMR 7039, CNRS, Vandoeuvre-les-Nancy (France)

    2011-10-15

    The authors report the determination of a strategy of use of different available imagery modalities on the Varian 3 On-Board-Imager (OBI): low energy (kV) and high energy (MV) plane imageries, and volume imagery (Kv-CBCT, cone beam computed tomography). The dose delivered by each device has been quantified on a humanoid phantom with thermoluminescent dosimeters. A prospective clinical compared the three modalities in terms of patient positioning accuracy. It appears that low-energy imagery provides a good reproducibility, a negligible additional dose and a better image quality. Short communication

  17. Effects on populations of exposure to low levels of ionizing radiation: implications for nuclear energy and medical radiation. The 1979 report of the Advisory Committee on the Biological Effects of Ionizing Radiation (The BEIR Report)

    International Nuclear Information System (INIS)

    Fabrikant, J.I.

    1979-04-01

    The following aspects of the 1979 BEIR report are described: societal decision-making; nuclear energy needs and medical care services; epidemiological and experimental studies; public acceptance; concept of risks to health; risk estimates and cost-benefit analysis; and comparison of risks. Other topics discussed are as follows: need for advisory committees on radiation; value of the BEIR report; health effects of low levels of ionizing radiation; determination of radiation risk estimates; and quantitation of radioinduced cancer risk estimates

  18. SU-E-T-332: Dosimetric Impact of Photon Energy and Treatment Technique When Knowledge Based Auto-Planning Is Implemented in Radiotherapy of Localized Prostate Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Z; Kennedy, A [Sarah Cannon, Nashville, TN (United States); Larsen, E; Grow, A; Hayes, C; Balamucki, C [North Florida Cancer Center, Gainesville, FL (United States); Salmon, H; Thompson, M [Lake City Cancer Center, Lake City, FL (United States)

    2015-06-15

    Purpose: The aim of this study was to investigate the dosimetric impact of the combination of photon energy and treatment technique on radiotherapy of localized prostate cancer when knowledge based planning was used. Methods: A total of 16 patients with localized prostate cancer were retrospectively retrieved from database and used for this study. For each patient, four types of treatment plans with different combinations of photon energy (6X and 10X) and treatment techniques (7-field IMRT and 2-arc VMAT) were created using a prostate DVH estimation model in RapidPlan™ and Eclipse treatment planning system (Varian Medical System). For any beam arrangement, DVH objectives and weighting priorities were generated based on the geometric relationship between the OAR and PTV. Photon optimization algorithm was used for plan optimization and AAA algorithm was used for final dose calculation. Plans were evaluated in terms of the pre-defined dosimetric endpoints for PTV, rectum, bladder, penile bulb, and femur heads. A Student’s paired t-test was used for statistical analysis and p > 0.05 was considered statistically significant. Results: For PTV, V95 was statistically similar among all four types of plans, though the mean dose of 10X plans was higher than that of 6X plans. VMAT plans showed higher heterogeneity index than IMRT plans. No statistically significant difference in dosimetry metrics was observed for rectum, bladder, and penile bulb among plan types. For left and right femur, VMAT plans had a higher mean dose than IMRT plans regardless of photon energy, whereas the maximum dose was similar. Conclusion: Overall, the dosimetric endpoints were similar regardless of photon energy and treatment techniques when knowledge based auto planning was used. Given the similarity in dosimetry metrics of rectum, bladder, and penile bulb, the genitourinary and gastrointestinal toxicities should be comparable among the selections of photon energy and treatment techniques.

  19. Use of I.G.R.T. for prostate cancers (O.B.I.-C.B.C.T. VarianTM, ExacTrac BrainLABTM and M.V.C.T. Tomo-therapy)

    International Nuclear Information System (INIS)

    Delpon, G.; Llagostera, C.; Lisbona, A.; Le Blanc, M.; Rio, E.; Supiot, S.; Mahe, M.A.

    2009-01-01

    Introduction: The aim of this work was to report the experience of image-guided radiotherapy at the C.L.C.C. Nantes-Atlantique using three repositioning imaging devices, the ExacTrac (BrainLABTM), the on-board imager cone beam computed tomography (O.B.I.-C.B.C.T.) (Varian TM ) and the M.V.C.T. (Tomotherapy Inc TM ), in the case of prostate external radiotherapy.Material and methods: For each linac and its imaging device, a treatment plan was described. Moreover, studies concerning calculated shifts after imaging sessions were achieved. Using ExacTrac, for eight patients, a study compared daily shifts based on bony anatomy or on implanted markers. Considering mean values of displacements over a course of radiotherapy, dosimetric impact was evaluated. With the O.B.I.-C.B.C.T., two imaging modalities were used, kV-kV (0. and 270.) and C.B.C.T.. Up to now, whatever the images, displacements were calculated using the bony anatomy. For both modalities and for 26 patients, shifts were compared. Since the beginning of the Tomotherapy HiArt use, mega voltage cone tomography (M.V.C.T.) was performed for each session of each patient. For 12 patients, mean displacements were calculated after five fractions. Then the deviations to those values were calculated. This was done to show the relevance of daily M.V.C.T.. Results and conclusion: This work allows us to report the use of three repositioning imaging devices in the radiotherapy department. At least: they provide an efficient positioning tool. And they let us see the future radiotherapy which would probably be the dose-guided radiotherapy. (N.C.)

  20. Medical aspects of renewable energy shown by the example of German hospitals; Umweltmedizinische Gesichtspunkte der regenerativen Energieerzeugung am Beispiel deutscher Krankenhaeuser

    Energy Technology Data Exchange (ETDEWEB)

    Waschnewski, R.

    2007-07-01

    To what extend are renewable energy sources used in German hospitals? This is the main objective, this is paper is dealing with. The energy consumption profile is very specific in hospitals. In a questionnaire based study, 79 hospitals have been questioned to elucidate the current situation in German hospitals with respect to energy consumption, and to get an idea of the proportion of alternative energy sources already in use. Our analysis reveals that 14% of the hospitals analysed are already using renewable energy sources. Main sources already utilized are photovoltaic, solar thermal devices, and to a lower extend geothermic energy as well comes into operation. Almost three quarters of the questioned institutions claim, they are aware of funding possibilities and the option of contracting with respect to providing financial support in relation to aquisition of new establishments of alternative energy systems within their institution. Roughly half of the hospital's technical supervisors are aware of the precise energy potential of their institution. The situation about information and awareness with respect to possibilities related to the usage of green energy is deficient and should be improved, but the openness with respect to the topic in general seems to be very positive and advantage of that climate should be taken. Our survey allowed to get an initial estimate on the green energy situation in German hospitals. The focus of the discussion is channeled towards the environmental aspects of the energy production. The survey data allow to conclude that the current information situation is deficient. The data further provide insight into what are the main barriers with respect to the use of renewable energy. Based on our results future analyses can not focus on specific aspects and further evaluate approaches allowing to extend the usage of alternative energy sources in hospitals. (orig.)

  1. Medical tourism.

    Science.gov (United States)

    Leggat, Peter

    2015-01-01

    Medical tourism is a burgeoning industry in our region. It involves patients travelling outside of their home country for medical treatment. This article provides an outline of the current research around medical tourism, especially its impact on Australians. Patients are increasingly seeking a variety of medical treatments abroad, particularly those involving cosmetic surgery and dental treatment, often in countries in South-East Asia. Adverse events may occur during medical treatment abroad, which raises medico-legal and insurance issues, as well as concerns regarding follow-up of patients. General practitioners need to be prepared to offer advice, including travel health advice, to patients seeking medical treatment abroad.

  2. Medical Management

    Science.gov (United States)

    ... org Close Charcot-Marie-Tooth Disease (CMT) Medical Management Although there’s no cure for CMT, there are ... individualized physical therapy program. For more on medical management of CMT, see Surgery Sometimes, Bracing Often, Caution ...

  3. Medical Identity

    DEFF Research Database (Denmark)

    Musaeus, Peter

    2015-01-01

    Purpose: To examine philosophical stances underpinning medical identity and assess the conceptual relationship between physician, medical practice and culture. Argument: Medical identity is about the ideals and moral positions that physicians take when justifying themselves. Medical identity...... hedonistic versus sentimentalist approaches to medical identity. The sociocultural philosophical analysis of medical identity can shed light on what it means conceptually for a physician to harbor beliefs associated with him/her being taken to be an autonomous professional. It is important because it touches...... on the meaning of being a compassionate, good and skilled physician, making its relevance to person-centered medicine self-evident. Conclusion: Medical identity should be analyzed with reference to literature, philosophy and medical practice in order for the physician to exercise a reflective position...

  4. [Medical negligence].

    Science.gov (United States)

    Zipper, St G

    2016-06-01

    Medical negligence is a matter of growing public interest. This review outlines various aspects of medical negligence: epidemiology, taxonomy, and the risks, causes, psychology, management and prevention of errors.

  5. Medical Illustration

    Science.gov (United States)

    ... as medical books, journals, magazines, pharma or biotech marketing, films, online video, exhibits, posters, wall charts, educational ... of the health career profession with strong communication skills, medical illustrators work closely with clients to interpret ...

  6. ENERGY MEDICINE

    OpenAIRE

    Srinivasan, T. M.

    1987-01-01

    Energy medicine is the most comprehensive concept introduced in medical diagnostics and therapy to account for a whole range of phenomena and methods available to help an individual proceed from sickness to health. The modern medical theories do not account for, much less accept many traditional therapies due to deep suspicion that the older methods are not scientific. However, the Holistic Health groups around the world have now created an environment for therapies which work at subtle energ...

  7. [Medical technology and medical education].

    Science.gov (United States)

    von Mallek, D; Biersack, H-J; Mull, R; Wilhelm, K; Heinz, B; Mellert, F

    2010-08-01

    The education of medical professionals is divided into medical studies, postgraduate training leading to the qualification as a specialist, and continuing professional development. During education, all scientific knowledge and practical skills are to be acquired, which enable the physician to practice responsibly in a specialized medical area. In the present article, relevant curricula are analyzed regarding the consideration of medical device-related topics, as the clinical application of medical technology has reached a central position in modern patient care. Due to the enormous scientific and technical progress, this area has become as important as pharmacotherapy. Our evaluation shows that medical device-related topics are currently underrepresented in the course of medical education and training and should be given greater consideration in all areas of medical education. Possible solutions are presented.

  8. Measurement of the neutron spectrum in a room with an accelerator Varian 2300C/D Linac using the Bonner multisphere spectrometer; Medicao do espectro de neutrons em uma sala com um acelerador Varian 2300C/D Linav usando o espectrometro de multiesferas de Bonner

    Energy Technology Data Exchange (ETDEWEB)

    Cavalcante, D.B.S., E-mail: cavalcante@ird.gov.b [Universidade Federal do Rio de Janeiro (IF/UFRJ), RJ (Brazil). Inst. de Fisica; Fonseca, E.S. da, E-mail: evaldo@ird.gov.b [Instituto de Radioprotecao e Dosimetria (IRD/CNEN-RJ), Rio de Janeiro, RJ (Brazil); Lemos Junior, R.M. [Coordenacao dos Programas de Pos-Graduacao de Engenharia (COPPE/UFRJ), RJ (Brazil); Batista, D.V.S. [Instituto Nacional do Cancer (INCa), Rio de Janeiro, RJ (Brazil)

    2009-07-01

    The generated neutron field varies considerably and depends on the beam energy, on the shielding of the accelerator, on the filters for beam homogeneity, and also on the mobile collimators and geometry of irradiation. The estimation of the component relative to the photoneutrons has practical interest for evaluation of the radiological risks for the workers and for the patient as well. Due to the high frequency magnetic field, and to the photon abundance resulting of the escape and scattering at treatment room, those measurements present some difficulties. Measurements of the neutron fields can be made with a Bonner spectrometer. Those system was calibrated with referred neutron standard sources and used for make measurements on a spot of the room where a Variant 2300C/D Linac is installed. The unfolding process used the BUNKI computer code for determination of the neutron spectra at the measurement spot

  9. The electron beam characteristics of energies up to 20 MeV and comparison of electron parameters of linear accelerators

    International Nuclear Information System (INIS)

    Awada, M.; Elleithy, M.A.; ElWihady, G.F.; Mostafa, K.A.

    2005-01-01

    The electron beams characteristics studded for the energies 4-20 MeV of Varian 23 EX ,experimental results are presented and compared with the published data. The CADD curves are measured for all energies and carried out the PDD of different applicator sizes ,that compared with the PDD of in the BJR. The quality beam parameters are determined from the CADD curves and calculated the yielded parameters of the corresponding electron energies which compared with the published data of other accelerators and theoretical Monte-Carlo calculation. The beam profiles are measured at different depths to construct the isodose distribution

  10. Comparison of Online 6 Degree-of-Freedom Image Registration of Varian TrueBeam Cone-Beam CT and BrainLab ExacTrac X-Ray for Intracranial Radiosurgery.

    Science.gov (United States)

    Li, Jun; Shi, Wenyin; Andrews, David; Werner-Wasik, Maria; Lu, Bo; Yu, Yan; Dicker, Adam; Liu, Haisong

    2017-06-01

    The study was aimed to compare online 6 degree-of-freedom image registrations of TrueBeam cone-beam computed tomography and BrainLab ExacTrac X-ray imaging systems for intracranial radiosurgery. Phantom and patient studies were performed on a Varian TrueBeam STx linear accelerator (version 2.5), which is integrated with a BrainLab ExacTrac imaging system (version 6.1.1). The phantom study was based on a Rando head phantom and was designed to evaluate isocenter location dependence of the image registrations. Ten isocenters at various locations representing clinical treatment sites were selected in the phantom. Cone-beam computed tomography and ExacTrac X-ray images were taken when the phantom was located at each isocenter. The patient study included 34 patients. Cone-beam computed tomography and ExacTrac X-ray images were taken at each patient's treatment position. The 6 degree-of-freedom image registrations were performed on cone-beam computed tomography and ExacTrac, and residual errors calculated from cone-beam computed tomography and ExacTrac were compared. In the phantom study, the average residual error differences (absolute values) between cone-beam computed tomography and ExacTrac image registrations were 0.17 ± 0.11 mm, 0.36 ± 0.20 mm, and 0.25 ± 0.11 mm in the vertical, longitudinal, and lateral directions, respectively. The average residual error differences in the rotation, roll, and pitch were 0.34° ± 0.08°, 0.13° ± 0.09°, and 0.12° ± 0.10°, respectively. In the patient study, the average residual error differences in the vertical, longitudinal, and lateral directions were 0.20 ± 0.16 mm, 0.30 ± 0.18 mm, 0.21 ± 0.18 mm, respectively. The average residual error differences in the rotation, roll, and pitch were 0.40°± 0.16°, 0.17° ± 0.13°, and 0.20° ± 0.14°, respectively. Overall, the average residual error differences were cone-beam computed tomography image registration in intracranial treatments.

  11. MaTech - the BMFT ''new materials'' materials research program - 1994 annual report about new materials for innovative information technology, energy technology, traffic engineering, medical engineering and production engineering applications, and about general materials research and new fields

    International Nuclear Information System (INIS)

    Lillack, D.; Gilbert, I.; Runte, S.

    1995-01-01

    This annual report gives a survey of projects supported within the framework of the Matfo and Ma-Tech programs. These projects focus on research into materials for innovative: 1. information technology, 2. energy technology, 3. traffic engineering, 4. medical engineering, and 5. production engineering applications and on 6. general materials research and new fields. The descriptions of individual projects indicate project goals and work schedules, names of important sub-contractors, and total costs and the funds contributed by BMFT. Information added in an annex includes inter alia a list of publications, lectures, contracts, or patents resulting from project activities in the year 1994. (MM) [de

  12. Medical marijuana.

    OpenAIRE

    Marmor, J B

    1998-01-01

    Although many clinical studies suggest the medical utility of marijuana for some conditions, the scientific evidence is weak. Many patients in California are self-medicating with marijuana, and physicians need data to assess the risks and benefits. The only reasonable solution to this problem is to encourage research on the medical effects of marijuana. The current regulatory system should be modified to remove barriers to clinical research with marijuana. The NIH panel has identified several...

  13. Estimation of the contribution of neutrons to the equivalent dose for personnel occupationally exposed and public in medical facilities: X-ray with energy equal or greater than 10MV

    International Nuclear Information System (INIS)

    Gonzalez, Alfonso Mayer; Jimenez, Roberto Ortega; Sanchez, Mario A. Reyes; Moranchel y Mejia, Mario

    2013-01-01

    In Mexico the use of electron accelerators for treating cancerous tumors had grown enormously in the last decade. When the treatments are carried out with X-ray beam energy below 10 MV the design of the shielding of the radioactive facility is determined by analyzing the interaction of X-rays, which have a direct impact and dispersion, with materials of the facility. However, when it makes use of X-ray beam energy equal to or greater than 10 MV the neutrons presence is imminent due to their generation by the interaction of the primary beam X-ray with materials head of the accelerator and of the table of treatment, mainly. In these cases, the design and calculation of shielding considers the generation of high-energy neutrons which contribute the equivalent dose that public and Occupationally Staff Exposed (POE) will receive in the areas surrounding the facility radioactive. However, very few measurements have been performed to determine the actual contribution to the neutron dose equivalent received by POE and public during working hours. This paper presents an estimate of the actual contribution of the neutron dose equivalent received by public and POE facilities in various radioactive medical use, considering many factors. To this end, measurements were made of the equivalent dose by using a neutron monitor in areas surrounding different radioactive installations (of Mexico) which used electron accelerators medical use during treatment with X-ray beam energy equal to or greater than 10 MV. The results are presented after a statistical analysis of a wide range of measures in order to estimate more reliability real contribution of the neutron dose equivalent for POE and the public. (author)

  14. Medical Terminology.

    Science.gov (United States)

    Mercer County Community Coll., Trenton, NJ.

    This document is one of a series of student workbooks developed for workplace skill development courses or workshops by Mercer County Community College (New Jersey) and its partners. Designed to help employees of medical establishments learn medical terminology, this course provides information on basic word structure, body parts, suffixes and…

  15. Uncertainties in the correction factors as the dose polarization and recombination at different energies; Incertidumbres en la medida de factores de correccion a la dosis por polarizacion y recombinacion a diferentes energias

    Energy Technology Data Exchange (ETDEWEB)

    Alejo Luque, L.; Rodriguez Romero, R.; Castro Tejero, P.; Fandino Lareo, J. M.

    2011-07-01

    This paper discusses the measures and uncertainties of the correction factors for dose-polarization (k, 1) and recombination (k,) of different ionization chambers plane-parallel and cylindrical. The values ??have been obtained using photon and electron beams of various energies generated by linear accelerators nominal Varian 21EX CLJNAC Tomotherapy Hi-Art and JI. We study the cases in which you can avoid the application of the factors obtained, according to the criteria proposed.

  16. Design and simulation of a short, variable-energy 4 to 10 MV S-band linear accelerator waveguide.

    Science.gov (United States)

    Baillie, Devin; Fallone, B Gino; Steciw, Stephen

    2017-06-01

    To modify a previously designed, short, 10 MV linac waveguide, so that it can produce any energy from 4 to 10 MV. The modified waveguide is designed to be a drop-in replacement for the 6 MV waveguide used in the author's current linear accelerator-magnetic resonance imager (Linac-MR). Using our group's previously designed short 10 MV linac as a starting point, the port was moved to the fourth cavity, the shift to the first coupling cavity was removed and a tuning cylinder added to the first coupling cavity. Each cavity was retuned using finite element method (FEM) simulations to resonate at the desired frequency. FEM simulations were used to determine the RF field distributions for various tuning cylinder depths, and electron trajectories were computed using a particle-in-cell model to determine the required RF power level and tuning cylinder depth to produce electron energy distributions for 4, 6, 8, and 10 MV photon beams. Monte Carlo simulations were then used to compare the depth dose profiles with those produced by published electron beam characteristics for Varian linacs. For each desired photon energy, the electron beam energy was within 0.5% of the target mean energy, the depth of maximum dose was within 1.5 mm of that produced by the Varian linac, and the ratio of dose at 10 cm depth to 20 cm depth was within 1%. A new 27.5 cm linear accelerator waveguide design capable of producing any photon energy between 4 and 10 MV has been simulated, however coupling port design and the implications of increased electron beam current at 10 MV remain to be investigated. For the specific cases of 4, 6, and 10 MV, this linac produces depth dose profiles similar to those produced by published spectra for Varian linacs. © 2017 American Association of Physicists in Medicine.

  17. Derivation of electron and photon energy spectra from electron beam central axis depth dose curves

    Energy Technology Data Exchange (ETDEWEB)

    Deng Jun [Department of Radiation Oncology, Stanford University School of Medicine, Stanford, CA 94305 (United States)]. E-mail: jun@reyes.stanford.edu; Jiang, Steve B.; Pawlicki, Todd; Li Jinsheng; Ma, C.M. [Department of Radiation Oncology, Stanford University School of Medicine, Stanford, CA 94305 (United States)

    2001-05-01

    A method for deriving the electron and photon energy spectra from electron beam central axis percentage depth dose (PDD) curves has been investigated. The PDD curves of 6, 12 and 20 MeV electron beams obtained from the Monte Carlo full phase space simulations of the Varian linear accelerator treatment head have been used to test the method. We have employed a 'random creep' algorithm to determine the energy spectra of electrons and photons in a clinical electron beam. The fitted electron and photon energy spectra have been compared with the corresponding spectra obtained from the Monte Carlo full phase space simulations. Our fitted energy spectra are in good agreement with the Monte Carlo simulated spectra in terms of peak location, peak width, amplitude and smoothness of the spectrum. In addition, the derived depth dose curves of head-generated photons agree well in both shape and amplitude with those calculated using the full phase space data. The central axis depth dose curves and dose profiles at various depths have been compared using an automated electron beam commissioning procedure. The comparison has demonstrated that our method is capable of deriving the energy spectra for the Varian accelerator electron beams investigated. We have implemented this method in the electron beam commissioning procedure for Monte Carlo electron beam dose calculations. (author)

  18. Cardiac Medications

    Science.gov (United States)

    ... cholesterol from circulating in the blood. Watch an animation of how statins work. Reason for Medication Used ... Kindle Fire Popular Articles 1 Understanding Blood Pressure Readings 2 Sodium and Salt 3 Heart Attack Symptoms ...

  19. Medication Guide

    Science.gov (United States)

    ... Size Small Text Medium Text Large Text Contrast Dark on Light Light on Dark Donate Search Menu Donate What is Glaucoma? Care ... Low Vision Resources Medication Guide Resources on the Web » See All Articles Where the Money Goes Have ...

  20. Medical imaging

    International Nuclear Information System (INIS)

    Loshkajian, A.

    2000-01-01

    This didactical book presents the medical imaging techniques: radiography, scanner, nuclear magnetic resonance (NMR). Examples are given for the most common pathologies in all domains of medicine. (J.S.)

  1. Medical Imaging.

    Science.gov (United States)

    Barker, M. C. J.

    1996-01-01

    Discusses four main types of medical imaging (x-ray, radionuclide, ultrasound, and magnetic resonance) and considers their relative merits. Describes important recent and possible future developments in image processing. (Author/MKR)

  2. Medical education.

    Science.gov (United States)

    Krishnan, P

    1992-01-01

    In theory, the Medical Council of India (MCI) determines the standards and qualifications of medical schools. It also sanctions curricula and ensures standards. Yet no standards exist on the mode of selection in medical schools, duration of study, course content, student stipends or period of internship. It takes 4.5 years to finish medical school. Students undergo preclinical, paraclinical, and clinical training. Most courses are in English which tends to favor the urban elite. Students cannot always communicate with patients in local languages. Textbooks often provide medical examples unrelated to India. Pedagogy consists mainly of lectures and rote learning predominates. Curricula tend not to provide courses in community health. Students pick up on the elitist attitudes of the faculty. For example, faculty do not put much emphasis on community health, individual health, equity in health care delivery, and teamwork. Further the education system is not patient oriented, but hospital or disease oriented. Faculty should train students in creating sanitation programs, knowing local nutritious foods, and in making community diagnoses. Yet they tend to be practitioners 1st then educators. Further faculty are not paid well and are not always invited to take part in improving curriculum, so morale is often low. Moreover experience in health planning and management issues is not required for administrators. In addition, medical schools are not well equipped with learning aids, libraries, or teaching staff. Tax revenues finance medical education. 75% of graduating physicians set up a private practice. Further many physicians go to urban areas. 34-57% emigrate to other countries. The problems of medical education will not be solved until the political and economic system becomes more responsive to the health needs of the people.

  3. Medical tourism

    OpenAIRE

    Abbas Ghanbari; Khadijeh Zirak Moradlu; Morteza Ramazani

    2014-01-01

    Medical tourism is considered as one of the tourism dimensions and it can contribute to the stabilized and dynamic development of a country's economy. Since it is cost-effective industry, most developing countries have focused on this industry and they are planning to develop this industry. Not only does Zanjan province, as the central region in medicine services, enjoy different kinds of variety and acceptable medical specialties but also it has historical, natural, and religious tourism pot...

  4. Medical Applications

    OpenAIRE

    Biscari, C.; Falbo, L.

    2016-01-01

    The use of accelerators for medical applications has evolved from initial experimentation to turn-key devices commonly operating in hospitals. New applications are continuously being developed around the world, and the hadrontherapy facilities of the newest generation are placed at the frontier between industrial production and advanced R&D. An introduction to the different medical application accelerators is followed by a description of the hadrontherapy facilities, with special emphasis on ...

  5. Medical radiation

    International Nuclear Information System (INIS)

    1992-01-01

    This leaflet in the At-a-Glance Series describes the medical use of X-rays, how X-rays help in diagnosis, radiation protection of the patient, staff protection, how radioactive materials in nuclear medicine examinations help in diagnosis and the use of radiation in radiotherapy. Magnetic resonance imaging, a diagnostic technique involving no ionizing radiation, is also briefly examined. The role of the NRPB in the medical use of radiation is outlined. (UK)

  6. Medical negligence.

    OpenAIRE

    Rosen, M.

    1992-01-01

    The progress made in diagnostic and therapeutic medicine has resulted in an increase in the number of malpractice suits brought against medical practitioners. To constitute negligence it must be shown that the conduct of the accused did not measure up to the standard of care the law required of him in the particular circumstances and that he acted with guilt and therefore can be blamed for the deed. This paper describes medical practitioner negligence and reviews relevant cases.

  7. SU-F-I-06: Evaluation of Imaging Dose for Modulation Layer Based Dual Energy Cone-Beam CT

    Energy Technology Data Exchange (ETDEWEB)

    Ju, Eunbin [Department of Medical Science, Ewha Womans University, Seoul (Korea, Republic of); Ahn, SoHyun; Cho, Samju; Keum, Ki Chang [Department of Radiation Oncology, School of Medicine, Yonsei Univeristy, Seoul (Korea, Republic of); Lee, Rena [Department of Radiation Oncology, School of Medicine, Ewha Womans University, Seoul (Korea, Republic of)

    2016-06-15

    Purpose: Dual energy cone beam CT system is finding a variety of promising applications in diagnostic CT, both in imaging of endogenous materials and exogenous materials across a range of body sites. Dual energy cone beam CT system to suggest in this study acquire image by rotating 360 degree with half of the X-ray window covered using copper modulation layer. In the region that covered by modulation layer absorb the low energy X-ray by modulation layer. Relative high energy X-ray passes through the layer and contributes to image reconstruction. Dose evaluation should be carried out in order to utilize such an imaging acquirement technology for clinical use. Methods: For evaluating imaging dose of modulation layer based dual energy cone beam CT system, Prototype cone beam CT that configured X-ray tube (D054SB, Toshiba, Japan) and detector (PaxScan 2520V, Varian Medical Systems, Palo Alto, CA) is used. A range of 0.5–2.0 mm thickness of modulation layer is implemented in Monte Carlo simulation (MCNPX, ver. 2.6.0, Los Alamos National Laboratory, USA) with half of X-ray window covered. In-house phantom using in this study that has 3 cylindrical phantoms configured water, Teflon air with PMMA covered for verifying the comparability the various material in human body and is implemented in Monte Carlo simulation. The actual dose with 2.0 mm copper covered half of X-ray window is measured using Gafchromic EBT3 film with 5.0 mm bolus for compared with simulative dose. Results: Dose in phantom reduced 33% by copper modulation layer of 2.0 mm. Scattering dose occurred in modulation layer by Compton scattering effect is 0.04% of overall dose. Conclusion: Modulation layer of that based dual energy cone beam CT has not influence on unnecessary scatter dose. This study was supported by the Radiation Safety Research Programs (1305033) through the Nuclear Safety and Security Commission.

  8. Evaluation of the GSO:Ce scintillator in the X-ray energy range from 40 to 140 kV for possible applications in medical X-ray imaging

    International Nuclear Information System (INIS)

    Nikolopoulos, D.; Valais, I.; Kandarakis, I.; Cavouras, D.; Linardatos, D.; Sianoudis, I.; Louizi, A.; Dimitropoulos, N.; Vattis, D.; Episkopakis, A.; Nomicos, C.; Panayiotakis, G.

    2006-01-01

    The purpose of the present study was to evaluate, under X-ray medical imaging conditions, the X-ray luminescence efficiency (XLE) and the optical quantum gain (OQG) of the Gd 2 SiO 5 :Ce scintillator in single crystal form, suitable for tomographic applications. Intrinsic physical properties and light emission characteristics of the Gd 2 SiO 5 :Ce scintillator, were also studied. Both experimental and Monte Carlo techniques were used. Various X-ray tube voltages (40-140 kV), currently employed in X-ray imaging applications, were used. XLE was found to vary slowly with X-ray tube voltage from (0.021±0.003) to (0.017±0.003). OQG varied from (317±18) to (466±23) light photons per incident X-ray. These values were adequately high for imaging applications using the particular energy range. Additionally, it was found by Monte Carlo simulations that for crystal thicknesses higher than 0.5 cm both XLE and OQG reached saturation levels, indicating that higher thickness crystals are of no practical use in X-ray medical imaging

  9. Medical tourism

    Directory of Open Access Journals (Sweden)

    Abbas Ghanbari

    2014-08-01

    Full Text Available Medical tourism is considered as one of the tourism dimensions and it can contribute to the stabilized and dynamic development of a country's economy. Since it is cost-effective industry, most developing countries have focused on this industry and they are planning to develop this industry. Not only does Zanjan province, as the central region in medicine services, enjoy different kinds of variety and acceptable medical specialties but also it has historical, natural, and religious tourism potentials. In this survey, the researcher investigated the existing potentials of Zanjan province based on descriptive - analytical tourism in offering and providing medical services and accommodation. The survey reports that offered services in tourism were not acceptable and satisfactory.

  10. Medical Applications

    CERN Document Server

    Biscari, C.

    2014-12-19

    The use of accelerators for medical applications has evolved from initial experimentation to turn-key devices commonly operating in hospitals. New applications are continuously being developed around the world, and the hadrontherapy facilities of the newest generation are placed at the frontier between industrial production and advanced R&D. An introduction to the different medical application accelerators is followed by a description of the hadrontherapy facilities, with special emphasis on CNAO, and the report closes with a brief outlook on the future of this field.

  11. Medical Applications

    International Nuclear Information System (INIS)

    Biscari, C; Falbo, L

    2014-01-01

    The use of accelerators for medical applications has evolved from initial experimentation to turn-key devices commonly operating in hospitals. New applications are continuously being developed around the world, and the hadrontherapy facilities of the newest generation are placed at the frontier between industrial production and advanced R&D. An introduction to the different medical application accelerators is followed by a description of the hadrontherapy facilities, with special emphasis on CNAO, and the report closes with a brief outlook on the future of this field

  12. Medical emplotment

    DEFF Research Database (Denmark)

    Mønsted, Troels Sune

    ’. Theoretically the project departs from Computer Supported Cooperative Work and Participatory Design and is informed by Medical Informatics, Design Research and Science and Technology Studies. Methodically the project is founded on collaborative prototyping, ethnographic studies, and design interventions...... philosophy and building on theory on narrative reasoning, the dissertation offers the notions of emplotment and re-emplotment to describe how physicians marshal information from various sources, including the medical record, the patient and coSummary to form a narrative, when making sense of patients...

  13. Planetary method to measure the neutrons spectrum in lineal accelerators of medical use

    International Nuclear Information System (INIS)

    Vega C, H. R.; Benites R, J. L.

    2014-08-01

    A novel procedure to measure the neutrons spectrum originated in a lineal accelerator of medical use has been developed. The method uses a passive spectrometer of Bonner spheres. The main advantage of the method is that only requires of a single shot of the accelerator. When this is used around a lineal accelerator is necessary to operate it under the same conditions so many times like the spheres that contain the spectrometer, activity that consumes enough time. The developed procedure consists on situating all the spheres of the spectrometer at the same time and to realize the reading making a single shot. With this method the photo neutrons spectrum produced by a lineal accelerator Varian ix of 15 MV to 100 cm of the isocenter was determined, with the spectrum is determined the total flow and the ambient dose equivalent. (Author)

  14. Validation of a virtual source model of medical linac for Monte Carlo dose calculation using multi-threaded Geant4

    Science.gov (United States)

    Aboulbanine, Zakaria; El Khayati, Naïma

    2018-04-01

    The use of phase space in medical linear accelerator Monte Carlo (MC) simulations significantly improves the execution time and leads to results comparable to those obtained from full calculations. The classical representation of phase space stores directly the information of millions of particles, producing bulky files. This paper presents a virtual source model (VSM) based on a reconstruction algorithm, taking as input a compressed file of roughly 800 kb derived from phase space data freely available in the International Atomic Energy Agency (IAEA) database. This VSM includes two main components; primary and scattered particle sources, with a specific reconstruction method developed for each. Energy spectra and other relevant variables were extracted from IAEA phase space and stored in the input description data file for both sources. The VSM was validated for three photon beams: Elekta Precise 6 MV/10 MV and a Varian TrueBeam 6 MV. Extensive calculations in water and comparisons between dose distributions of the VSM and IAEA phase space were performed to estimate the VSM precision. The Geant4 MC toolkit in multi-threaded mode (Geant4-[mt]) was used for fast dose calculations and optimized memory use. Four field configurations were chosen for dose calculation validation to test field size and symmetry effects, , , and for squared fields, and for an asymmetric rectangular field. Good agreement in terms of formalism, for 3%/3 mm and 2%/3 mm criteria, for each evaluated radiation field and photon beam was obtained within a computation time of 60 h on a single WorkStation for a 3 mm voxel matrix. Analyzing the VSM’s precision in high dose gradient regions, using the distance to agreement concept (DTA), showed also satisfactory results. In all investigated cases, the mean DTA was less than 1 mm in build-up and penumbra regions. In regards to calculation efficiency, the event processing speed is six times faster using Geant4-[mt] compared to sequential

  15. Nanoporous sputtered platinum-iridium-thinfilms for medical and energy applications; Nanoporoese gesputterte Platin-Iridium-Schichten fuer Anwendungen in der Medizin- und Energietechnik

    Energy Technology Data Exchange (ETDEWEB)

    Ganske, Gerald

    2012-10-05

    Sputtering makes it possible to create thinfilms of only a few atom layers and to customize them for special applications by adjusting the deposition parameters. In this work interface-layers are deposited and characterized in biological systems as stimulation electrodes for neural cells and as catalysts in hydrogen fuel cells. First of all, highly porous platinum films were created by sputtering at a pressure of 9 Pa and low power of less than 100 W. These parameters are an ideal compromise between deposition rate, porosity and disordered crystal structure of the layers. Investigations on co-sputtered platinum-iridium-films (PtIr) showed that these films form homogeneous structures and no distinction between the separate layers is possible. It was demonstrated that these films obtain the crystal structure of Pt as well as the finer cauliflower-like structure of iridium, if the atoms reach the substrate surface only with their thermal energy. Furthermore, it was shown that the film composition reflects the sputtering power of the separate targets in a linear way. The structure of the films can be predicted by means of monte-carlo-simulation, which was verified by SEM-pictures. The ratio of the sputtering power can be used to control the amount of interface elements which was confirmed by electrochemical tests. Electrode materials for the stimulation of neural cells need a large electrochemically active surface that allows for an interface between electron and ion conductivity. Test on platinum, iridium and PtIr have shown that the films sputtered at the lowest impact energy do have the largest active surface as well as the largest charge delivery capacity (CDC). Iridium films show the highest CDC (48 mC/cm{sup 2}), followed by platinum-iridium (2 mC/cm{sup 2}, 100 W power at both targets) and pure platinum (16 mC/cm{sup 2}). This can be explained by the large surface area of iridium and its electrochemical activation process. Although PtIr layers also show an

  16. Tests of an electron monitor for routine quality control measurements of electron energies

    International Nuclear Information System (INIS)

    Ramsay, E.B.; Reinstein, L.E.; Meek, A.G.

    1991-01-01

    The depth dose for electrons is sensitive to energy and the AAPM Task Group 24 has recommended that tests be performed at monthly intervals to assure electron beam energy constancy by verifying the depth for the 80% dose to within ±3 mm. Typically, this is accomplished by using a two-depth dose ratio technique. Recently, a new device, the Geske monitor, has been introduced that is designed for verifying energy constancy in a single reading. The monitor consists of nine parallel plate detectors that alternate with 5-mm-thick absorbers made of an aluminum alloy. An evaluation of the clinical usefulness of this monitor for the electron beams available on a Varian Clinac 20 has been undertaken with respect to energy discrimination. Beam energy changes of 3 mm of the 80% dose give rise to measurable output changes ranging from 1.7% for 20-MeV electron beams to 15% for 6-MeV electron beams

  17. Medical negligence

    African Journals Online (AJOL)

    Enrique

    19. SA JOURNAL OF RADIOLOGY • August 2004. Abstract. The progress made in diagnostic and therapeutic medicine has resulted in an increase in the number of malprac- tice suits brought against medical practitioners. To constitute negligence it must be shown that the conduct of the accused did not measure up to the.

  18. Medical Devices

    NARCIS (Netherlands)

    Verkerke, Gijsbertus Jacob; Mahieu, H.F.; Geertsema, A.A.; Hermann, I.F.; van Horn, J.R.; Hummel, J. Marjan; van Loon, J.P.; Mihaylov, D.; van der Plaats, A.; Schraffordt Koops, H.; Schutte, H.K.; Veth, R.P.H.; de Vries, M.P.; Rakhorst, G.; Shi, Donglu

    2004-01-01

    The development of new medical devices is a very time-consuming and costly process. Besides the time between the initial idea and the time that manufacturing and testing of prototypes takes place, the time needed for the development of production facilities, production of test series, marketing,

  19. Medical Malpractice

    DEFF Research Database (Denmark)

    Grembi, Veronica

    2014-01-01

    MM first came to the attention of policy makers primarily in the USA where, from the 1970s, healthcare providers denounced problems in getting insurance for medical liability, pointing out to a crisis in the MM insurance market (Sage WM (2003) Understanding the first malpractice crisis of the 21th...

  20. Medical marijuana

    Science.gov (United States)

    ... different amounts of cannabinoids. This sometimes makes the effects of medical marijuana hard to predict or control. The effects also ... wasting syndrome) Severe muscle spasms Multiple sclerosis Side Effects ... physical symptoms from using marijuana include: A fast or irregular heartbeat Dizziness Slow ...

  1. [Medical geography].

    Science.gov (United States)

    Hauri, D

    2007-10-17

    Hippocrates already noted that geographical factors such as climate, relief, geology but also settlement patterns had influenced the distribution of diseases. The task of medical geography is to investigate the associations between geographical factors and diseases. Thereby, geographic techniques and concepts are applied on health problems. Of particular importance is the mapping of diseases whose causes are environmental-related. In addition, epidemiological, ecological but also social scientific studies play an important part in the investigation of the associations between geographical factors and diseases. In order to understand the associations between the spatial distribution of diseases and environmental exposures, geographic information systems as well as statistical analyses have recently become more important. Some authors regard medical geography merely as supporting discipline of medicine. Nevertheless, as men and environment future and as they play an important part in the diffusion of diseases being regarded as defeated, medical geography will play an important part concerning medical questions. Especially travel medicine will rely on geographic knowledge, if a patient has to be consulted who plans to travel to an unknown country of which knowledge on the geographical distribution and ecology of diseases will be necessary.

  2. Transportation Energy - Sandia Energy

    Science.gov (United States)

    Energy Energy Secure & Sustainable Energy Future Search Icon Sandia Home Locations Contact Us Employee Locator Menu Stationary Power solar Energy Conversion Efficiency Increasing the amount of electricity produced from a given thermal energy input. Solar Energy Wind Energy Water Power Supercritical CO2

  3. Energy Research - Sandia Energy

    Science.gov (United States)

    Energy Energy Secure & Sustainable Energy Future Search Icon Sandia Home Locations Contact Us Employee Locator Menu Stationary Power solar Energy Conversion Efficiency Increasing the amount of electricity produced from a given thermal energy input. Solar Energy Wind Energy Water Power Supercritical CO2

  4. Medical imaging

    CERN Document Server

    Townsend, David W

    1996-01-01

    Since the introduction of the X-ray scanner into radiology almost 25 years ago, non-invasive imaging has become firmly established as an essential tool in the diagnosis of disease. Fully three-dimensional imaging of internal organs is now possible, b and for studies which explore the functional status of the body. Powerful techniques to correlate anatomy and function are available, and scanners which combine anatomical and functional imaging in a single device are under development. Such techniques have been made possible through r ecent technological and mathematical advances. This series of lectures will review both the physical basis of medical imaging techniques using X-rays, gamma and positron emitting radiosiotopes, and nuclear magnetic resonance, and the mathematical methods used to reconstruct three-dimentional distributions from projection data. The lectures will trace the development of medical imaging from simple radiographs to the present-day non-invasive measurement of in vivo biochemistry. They ...

  5. Medical imaging

    International Nuclear Information System (INIS)

    Elliott, Alex

    2005-01-01

    Diagnostic medical imaging is a fundamental part of the practice of modern medicine and is responsible for the expenditure of considerable amounts of capital and revenue monies in healthcare systems around the world. Much research and development work is carried out, both by commercial companies and the academic community. This paper reviews briefly each of the major diagnostic medical imaging techniques-X-ray (planar and CT), ultrasound, nuclear medicine (planar, SPECT and PET) and magnetic resonance. The technical challenges facing each are highlighted, with some of the most recent developments. In terms of the future, interventional/peri-operative imaging, the advancement of molecular medicine and gene therapy are identified as potential areas of expansion

  6. Medical surveillance of occupationally exposed workers

    International Nuclear Information System (INIS)

    2007-05-01

    The guide covers medical surveillance of workers engaged in radiation work and their fitness for this work, protection of the foetus and infant during the worker's pregnancy or breastfeeding, and medical surveillance measures to be taken when the dose limit has been exceeded. The guide also covers recognition of practitioners responsible for medical surveillance of category A workers, medical certificates to be issued to workers, and preservation and transfer of medical records. The medical surveillance requirements specified in this Guide cover the use of radiation and nuclear energy. The guide also applies to exposure to natural radiation in accordance with section 28 of the Finnish Radiation Decree

  7. Medical surveillance of occupationally exposed workers

    Energy Technology Data Exchange (ETDEWEB)

    2007-05-15

    The guide covers medical surveillance of workers engaged in radiation work and their fitness for this work, protection of the foetus and infant during the worker's pregnancy or breastfeeding, and medical surveillance measures to be taken when the dose limit has been exceeded. The guide also covers recognition of practitioners responsible for medical surveillance of category A workers, medical certificates to be issued to workers, and preservation and transfer of medical records. The medical surveillance requirements specified in this Guide cover the use of radiation and nuclear energy. The guide also applies to exposure to natural radiation in accordance with section 28 of the Finnish Radiation Decree

  8. Medication Errors - A Review

    OpenAIRE

    Vinay BC; Nikhitha MK; Patel Sunil B

    2015-01-01

    In this present review article, regarding medication errors its definition, medication error problem, types of medication errors, common causes of medication errors, monitoring medication errors, consequences of medication errors, prevention of medication error and managing medication errors have been explained neatly and legibly with proper tables which is easy to understand.

  9. Undergraduate medical education.

    Science.gov (United States)

    Rees, L; Wass, J

    1993-01-23

    Pressures from students and teachers, from professional bodies, and from changes in the way health care is delivered are all forcing a rethink of how medical students should be taught. These pressures may be more intense in London but are not confined to it. The recommendation the Tomlinson report advocates that has been generally welcomed is for more investment in primary care in London. General practitioners have much to teach medical schools about effective ways of learning, but incentives for teaching students in general practice are currently low, organising such teaching is difficult and needs resources, and resistance within traditional medical school hierarchies needs to be overcome. Likewise, students value learning within local communities, but the effort demanded of public health departments and community organisations is great at a time when they are under greater pressure than ever before. The arguments over research that favour concentration in four multifaculty schools are less clear cut for undergraduate education, where personal support for students is important. An immediate concern is that the effort demanded for reorganising along the lines suggested by Tomlinson will not leave medical schools much energy for innovating.

  10. Medical robotics

    CERN Document Server

    Troccaz, Jocelyne

    2013-01-01

    In this book, we present medical robotics, its evolution over the last 30 years in terms of architecture, design and control, and the main scientific and clinical contributions to the field. For more than two decades, robots have been part of hospitals and have progressively become a common tool for the clinician. Because this domain has now reached a certain level of maturity it seems important and useful to provide a state of the scientific, technological and clinical achievements and still open issues. This book describes the short history of the domain, its specificity and constraints, and

  11. The dosimetric effects of photon energy on the quality of prostate volumetric modulated arc therapy.

    Science.gov (United States)

    Mattes, Malcolm D; Tai, Cyril; Lee, Alvin; Ashamalla, Hani; Ikoro, N C

    2014-01-01

    Studies comparing the dosimetric effects of high- and low-energy photons to treat prostate cancer using 3-dimensional conformal and intensity modulated radiation therapy have yielded mixed results. With the advent of newer radiation delivery systems like volumetric modulated arc therapy (VMAT), the impact of changing photon energy is readdressed. Sixty-five patients treated for prostate cancer at our institution from 2011 to 2012 underwent CT simulation. A target volume encompassing the prostate and entire seminal vesicles was treated to 50.4 Gy, followed by a boost to the prostate and proximal seminal vesicles to a total dose of 81 Gy. The VMAT plans were generated for 6-MV and 10-MV photons under identical optimization conditions using the Eclipse system version 8.6 (Varian Medical Systems, Palo Alto, CA). The analytical anisotropic algorithm was used for all dose calculations. Plans were normalized such that 98% of the planning target volume (PTV) received 100% of the prescribed dose. Dose-volumetric data from the treatment planning system was recorded for both 6-MV and 10-MV plans, which were compared for both the entire cohort and subsets of patients stratified according to the anterior-posterior separation. Plans using 10-MV photons had statistically significantly lower relative integral dose (4.1%), gradient measure (4.1%), skin Dmax (16.9%), monitor units (13.0%), and bladder V(30) (3.1%) than plans using 6-MV photons (P photons was more pronounced for thicker patients (anterior-posterior separation >21 cm) for most parameters, with statistically significant differences in bladder V(30), bladder V(65), integral dose, conformity index, and monitor units. The main dosimetric benefits of 10-MV as compared with 6-MV photons are seen in thicker patients, though for the entire cohort 10-MV plans resulted in a lower integral dose, gradient measure, skin Dmax, monitor units, and bladder V(30), possibly at the expense of higher rectum V(81). Copyright © 2014

  12. Medical robotics.

    Science.gov (United States)

    Ferrigno, Giancarlo; Baroni, Guido; Casolo, Federico; De Momi, Elena; Gini, Giuseppina; Matteucci, Matteo; Pedrocchi, Alessandra

    2011-01-01

    Information and communication technology (ICT) and mechatronics play a basic role in medical robotics and computer-aided therapy. In the last three decades, in fact, ICT technology has strongly entered the health-care field, bringing in new techniques to support therapy and rehabilitation. In this frame, medical robotics is an expansion of the service and professional robotics as well as other technologies, as surgical navigation has been introduced especially in minimally invasive surgery. Localization systems also provide treatments in radiotherapy and radiosurgery with high precision. Virtual or augmented reality plays a role for both surgical training and planning and for safe rehabilitation in the first stage of the recovery from neurological diseases. Also, in the chronic phase of motor diseases, robotics helps with special assistive devices and prostheses. Although, in the past, the actual need and advantage of navigation, localization, and robotics in surgery and therapy has been in doubt, today, the availability of better hardware (e.g., microrobots) and more sophisticated algorithms(e.g., machine learning and other cognitive approaches)has largely increased the field of applications of these technologies,making it more likely that, in the near future, their presence will be dramatically increased, taking advantage of the generational change of the end users and the increasing request of quality in health-care delivery and management.

  13. Medical revolution in Argentina.

    Science.gov (United States)

    Ballarin, V L; Isoardi, R A

    2010-01-01

    The paper discusses the major Argentineans contributors, medical physicists and scientists, in medical imaging and the development of medical imaging in Argentina. The following are presented: history of medical imaging in Argentina: the pioneers; medical imaging and medical revolution; nuclear medicine imaging; ultrasound imaging; and mathematics, physics, and electronics in medical image research: a multidisciplinary endeavor.

  14. Fiscal 1999 research report on long-term energy technology strategy. Basic research on industrial technology strategy (Individual technology strategy). Human life, medical care and welfare field (Medical health care technology field); 1999 nendo choki energy gijujtsu senryaku ni kansuru chosa hokokusho. Sangyo gijutsu senryaku sakutei kiban chosa (bun'yabetsu gijutsu senryaku) ningen seikatsu iryo fukushi bun'ya (medidal health care gijutsu bun'ya)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-03-01

    This report summarizes the fiscal 1999 research result on Japanese technology competitiveness, future trend, technology innovation and policy needs in a medical health care field. Future international growth of a medical health care equipment industry is promising because of an expected progress of medical care technology, change in medical care needs and creation of the new global market. The current highlighted technical trend is fusion of medical technology with network, system, biotechnology and micro-machine technologies, and such fusion is expected to contribute to daily use, less/no invasion and improvement of medical treatment. Industry-government cooperative measures for upgrading an international competitiveness are as follows: an approach as national policy by preparing Japanese BECOM, preparation of a system supporting venture businesses for developing medical health care equipment, and systematic establishment of a medical-engineering cooperative system. Preparation of a complementary relation with overseas countries is also desirable. (NEDO)

  15. Medications (for IBS)

    Medline Plus

    Full Text Available ... July 2017 Print Jump to Topic Medications for IBS Laxatives Anticholinergic/Antispasmodic Agents Antidiarrheal Agents Antidepressant Medications Newer IBS Medications Probiotics and Antibiotics Pharmacologic, ...

  16. Smoking cessation medications

    Science.gov (United States)

    Smoking cessation - medications; Smokeless tobacco - medications; Medications for stopping tobacco ... Smoking cessation medicines can: Help with the craving for tobacco. Help you with withdrawal symptoms. Keep you ...

  17. Medical humanities in the undergraduate medical curriculum.

    Science.gov (United States)

    Supe, Avinash

    2012-01-01

    The medical humanities have been introduced in medical curricula over the past 30 years in the western world. Having medical humanities in a medical school curriculum can nurture positive attitudes in the regular work of a clinician and contribute equally to personality development. Though substantial evidence in favour of a medical humanities curriculum may be lacking, the feedback is positive. It is recommended that medical humanities be introduced into the curriculum of every medical school with the purpose of improving the quality of healthcare, and the attitudes of medical graduates.

  18. Medical telesensors

    Science.gov (United States)

    Ferrell, Trinidad L.; Crilly, P. B.; Smith, S. F.; Wintenberg, Alan L.; Britton, Charles L., Jr.; Morrison, Gilbert W.; Ericson, M. N.; Hedden, D.; Bouldin, Donald W.; Passian, A.; Downey, Todd R.; Wig, A. G.; Meriaudeau, Fabrice

    1998-05-01

    Medical telesensors are self-contained integrated circuits for measuring and transmitting vital signs over a distance of approximately 1-2 meters. The circuits are unhoused and contain a sensor, signal processing and modulation electronics, a spread-spectrum transmitter, an antenna and a thin-film battery. We report on a body-temperature telesensor, which is sufficiently small to be placed on a tympanic membrane in a child's ear. We also report on a pulse-oximeter telesensor and a micropack receiver/long- range transmitter unit, which receives form a telesensor array and analyzes and re-transmits the vital signs over a longer range. Signal analytics are presented for the pulse oximeter, which is currently in the form of a finger ring. A multichip module is presented as the basic signal-analysis component. The module contains a microprocessor, a field=programmable gate array, memory elements and other components necessary for determining trauma and reporting signals.

  19. [MEDICAL CANNABIS].

    Science.gov (United States)

    Naftali, Timna

    2016-02-01

    The cannabis plant has been known to humanity for centuries as a remedy for pain, diarrhea and inflammation. Current research is inspecting the use of cannabis for many diseases, including multiple sclerosis, epilepsy, dystonia, and chronic pain. In inflammatory conditions cannabinoids improve pain in rheumatoid arthritis and:pain and diarrhea in Crohn's disease. Despite their therapeutic potential, cannabinoids are not free of side effects including psychosis, anxiety, paranoia, dependence and abuse. Controlled clinical studies investigating the therapeutic potential of cannabis are few and small, whereas pressure for expanding cannabis use is increasing. Currently, as long as cannabis is classified as an illicit drug and until further controlled studies are performed, the use of medical cannabis should be limited to patients who failed conventional better established treatment.

  20. Medical treatment of concussion.

    Science.gov (United States)

    Wright, Justin M

    2014-08-01

    A concussion is a brain injury, a change in function induced by traumatic forces. The incidence of concussion is increasing, likely due to increased awareness and improvement in recognition. Speech and language pathology professionals working in schools may encounter patients who have suffered concussions. At the root of concussion pathophysiology is altered metabolism and an acquired energy deficit. The mainstay of treatment for concussion is cognitive and physical rest, allowing for normalization of the metabolism and correction of the energy deficit. Once recovered, the student may need accommodations to successfully return to school without added difficulty and should follow a return to play protocol to return to athletics safely. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

  1. SU-F-T-279: Impact of Beam Energy Drifts On IMRT Delivery Accuracy

    International Nuclear Information System (INIS)

    Goddu, S; Kamal, G; Herman, A; Edwards, S; Cai, B; Yaddanapudi, S; Oddiraju, S; Rangaraj, D; Mutic, S

    2016-01-01

    found to be within clinically acceptable tolerance. However, this study includes a single energy with limited range of PDD change. Further studies are on going and the results will be presented. Received funding from Varian Medical Systems, Palo Alto, CA

  2. Medications (for IBS)

    Medline Plus

    Full Text Available ... Agents Antidepressant Medications Newer IBS Medications Probiotics and Antibiotics Pharmacologic, or drug, therapy is best used in ... Agents Antidepressant Medications Newer IBS Medications Probiotics and ... Treatments Understanding Stress Cognitive Behavioral Therapy Relaxation ...

  3. Medications (for IBS)

    Medline Plus

    Full Text Available ... Agents Antidiarrheal Agents Antidepressant Medications Newer IBS Medications Probiotics and Antibiotics Pharmacologic, or drug, therapy is best ... Agents Antidiarrheal Agents Antidepressant Medications Newer IBS Medications ... Psychological Treatments Understanding Stress Cognitive Behavioral ...

  4. The Medical Home

    Science.gov (United States)

    ... Videos for Educators Search English Español The Medical Home KidsHealth / For Parents / The Medical Home What's in ... for your child. What Does the Term "Medical Home" Mean? A medical home isn't a place ...

  5. Medications (for IBS)

    Medline Plus

    Full Text Available ... Agents Antidepressant Medications Newer IBS Medications Probiotics and Antibiotics Pharmacologic, or drug, therapy is best used in ... Agents Antidepressant Medications Newer IBS Medications Probiotics and Antibiotics Psychological Treatments Understanding Stress Cognitive Behavioral Therapy Relaxation ...

  6. Radiation Physics for Medical Physicists

    CERN Document Server

    Podgorsak, Ervin B

    2010-01-01

    This well-received textbook and reference summarizes the basic knowledge of atomic, nuclear, and radiation physics that professionals working in medical physics and biomedical engineering need for efficient and safe use of ionizing radiation. Concentrating on the underlying principles of radiation physics, it covers the prerequisite knowledge for medical physics courses on the graduate and post-graduate levels in radiotherapy physics, radiation dosimetry, imaging physics, and health physics, thus providing the link between elementary physics on the one hand and the intricacies of the medical physics specialties on the other hand. This expanded and revised second edition offers reorganized and expanded coverage. Several of the original chapters have been split into two with new sections added for completeness and better flow. New chapters on Coulomb scattering; on energy transfer and energy absorption in photon interactions; and on waveguide theory have been added in recognition of their importance. Others tra...

  7. Shielding for Critical Organs and Radiation Exposure Dose Distribution in Patients with High Energy Radiotherapy

    International Nuclear Information System (INIS)

    Chu, Sung Sil; Suh, Chang Ok; Kim, Gwi Eon

    2002-01-01

    High energy photon beams from medical linear accelerators produce large scattered radiation by various components of the treatment head, collimator and walls or objects in the treatment room including the patient. These scattered radiation do not provide therapeutic dose and are considered a hazard from the radiation safety perspective. Scattered dose of therapeutic high energy radiation beams are contributed significant unwanted dose to the patient. ICRP take the position that a dose of 500mGy may cause abortion at any stage of pregnancy and that radiation detriment to the fetus includes risk of mental retardation with a possible threshold in the dose response relationship around 100 mGy for the gestational period. The ICRP principle of As Low As Reasonably Achievable (ALARA) was recommended for protection of occupation upon the linear no-threshold dose response hypothesis for cancer induction. We suggest this ALARA principle be applied to the fetus and testicle in therapeutic treatment. Radiation dose outside a photon treatment filed is mostly due to scattered photons . This scattered dose is a function of the distance from the beam edge, treatment geometry, primary photon energy, and depth in the patient. The need for effective shielding of the fetus and testicle is reinforced when young patients are treated with external beam radiation therapy and then shielding designed to reduce the scattered photon dose to normal organs have to considered. Irradiation was performed in phantom using high energy photon beams produced by a Varian 2100C/D medical linear accelerator (Varian Oncology Systems, Polo Alto, CA) located at the Yonsei Cancer Center. The composite phantom used was comprised of a commercially available anthropomorphic Rando phantom (Phantom Laboratory Inc., Salem, YN) and a rectangular solid polystyrene phantom of dimensions 30cm x 30cm x 20cm. The anthropomorphic Rando phantom represents an average man made from tissue equivalent materials that is

  8. Shielding for Critical Organs and Radiation Exposure Dose Distribution in Patients with High Energy Radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Chu, Sung Sil; Suh, Chang Ok; Kim, Gwi Eon [Yonsei Univ., Seoul (Korea, Republic of)

    2002-03-15

    High energy photon beams from medical linear accelerators produce large scattered radiation by various components of the treatment head, collimator and walls or objects in the treatment room including the patient. These scattered radiation do not provide therapeutic dose and are considered a hazard from the radiation safety perspective. Scattered dose of therapeutic high energy radiation beams are contributed significant unwanted dose to the patient. ICRP take the position that a dose of 500mGy may cause abortion at any stage of pregnancy and that radiation detriment to the fetus includes risk of mental retardation with a possible threshold in the dose response relationship around 100 mGy for the gestational period. The ICRP principle of As Low As Reasonably Achievable (ALARA) was recommended for protection of occupation upon the linear no-threshold dose response hypothesis for cancer induction. We suggest this ALARA principle be applied to the fetus and testicle in therapeutic treatment. Radiation dose outside a photon treatment filed is mostly due to scattered photons . This scattered dose is a function of the distance from the beam edge, treatment geometry, primary photon energy, and depth in the patient. The need for effective shielding of the fetus and testicle is reinforced when young patients are treated with external beam radiation therapy and then shielding designed to reduce the scattered photon dose to normal organs have to considered. Irradiation was performed in phantom using high energy photon beams produced by a Varian 2100C/D medical linear accelerator (Varian Oncology Systems, Polo Alto, CA) located at the Yonsei Cancer Center. The composite phantom used was comprised of a commercially available anthropomorphic Rando phantom (Phantom Laboratory Inc., Salem, YN) and a rectangular solid polystyrene phantom of dimensions 30cm x 30cm x 20cm. The anthropomorphic Rando phantom represents an average man made from tissue equivalent materials that is

  9. Medical muddle.

    Science.gov (United States)

    Gartrell, Nanette

    2014-01-01

    Nanette Gartrell, MD, is a psychiatrist and researcher whose investigations have documented the mental health and psychological well-being of lesbian, gay, bisexual, and transgender (LGBT) people over the past four decades. Nanette is the principal investigator of an ongoing longitudinal study of lesbian families in which the children were conceived by donor insemination. Now in its 27th year, this project has been cited internationally in the debates over equality in marriage, foster care, and adoption. Previously on the faculty at Harvard Medical School and the University of California, San Francisco, Nanette is currently a Visiting Distinguished Scholar at the Williams Institute, UCLA School of Law. In 2013, Nanette received the Association of Women Psychiatrists Presidential Commendation Award for "selfless and enduring vision, leadership, wisdom, and mentorship in the fields of women's mental health, ethics, and gender research." At the age of 63, Nanette experienced a 3 ½ month period of intractable, incapacitating dizziness for which there was never a clear diagnosis.

  10. MEDICAL PROFESSIONALISH

    Directory of Open Access Journals (Sweden)

    Jože Drinovec

    2002-12-01

    Full Text Available Background. Due to restrictions imposed on a clinical freedom, interest for professionalism in healthcare has been getting bigger not only in medicine literature and various mass media but also in teaching and organisation of healthcare. Professionalism stands not only for a medicine’s contract with society, recognition of a physician status, privilege and monopoly but also for a genuine physician’s commitment to professional responsibilities.Analysis. In 2002 European and American associations approved a document on medical professionalism in the new millenium, so-called Physician Charter. This document includes fundamental principles of professionalism such as altruism, patient autonomy and social justice. In particular, it analyses a physician’s professional competency, honesty with patients, patient confidentiality, appropriate relations with patients, improvements regarding a healthcare quality, healthcare access, just distribution of finite funds, commitment to scientific knowledge, trust maintenance by managing conflicts of interest and a professional responsibility.Conclusions. Physician’s professionalism means philosophycal and sociological analysis of his/her profession and its position in a society. It includes a concern for improvements of his/ her own scientific knowledge, skills, a genuine ethic interest for an individual patient bearing in mind principles of equality and justice in society. Whether performing an organisational and public work or participating in professional health organizations, physician’s interest for a patient must prevail.

  11. Advanced Accelerators for Medical Applications

    Science.gov (United States)

    Uesaka, Mitsuru; Koyama, Kazuyoshi

    We review advanced accelerators for medical applications with respect to the following key technologies: (i) higher RF electron linear accelerator (hereafter “linac”); (ii) optimization of alignment for the proton linac, cyclotron and synchrotron; (iii) superconducting magnet; (iv) laser technology. Advanced accelerators for medical applications are categorized into two groups. The first group consists of compact medical linacs with high RF, cyclotrons and synchrotrons downsized by optimization of alignment and superconducting magnets. The second group comprises laser-based acceleration systems aimed of medical applications in the future. Laser plasma electron/ion accelerating systems for cancer therapy and laser dielectric accelerating systems for radiation biology are mentioned. Since the second group has important potential for a compact system, the current status of the established energy and intensity and of the required stability are given.

  12. Ultimate Choice for Energy: The Nuclear Energy

    Directory of Open Access Journals (Sweden)

    Metin Yıldırım*

    2007-06-01

    Full Text Available Increases in the prices of oil, hard coal and natural gas, emergence of Russia as a not reliable resource for the natural and the developments in the security of the energy supply again have been started the nuclear energy as a hotly debated issue in the world. This is also a sensitive topic among the opponents and proponents of the nuclear energy in Turkey. Nuclear energy is very important since it provides about 17 % of the electric energy in the world and is used in industry and medical area. However, Turkey has not declared any policy about this yet, because of the worries about the environmental reasons and has not gained any progress about nuclear energy. First of all, Turkey must use her geothermal, hydropower, hard coal, solar and wind energies. Otherwise, Turkey may find herself in a competition with her neighboring countries

  13. Linacs for medical isotope production

    International Nuclear Information System (INIS)

    Pramudita, A.

    2012-01-01

    This paper reviews efforts on using high energy (25-30 MeV) and high power (10-20 kW) electron linacs and lower energy (7 MeV) proton linacs for medical radioisotope production. Using high energy x-rays from the electron linacs, PET (Positron Emission Tomography) radioisotopes are produced through photonuclear reactions such as 19 F(γ,n) 18 F, which also allow production of other PET radionuclides 11 C, 13 N, and 15 O. Other mostly used medical radionuclides 99m Tc can also be obtained by using the electron linacs, through photofission or photonuclear reactions. Proton linacs for PET have also been recently developed and the product has been available in the market since 2005. The linacs have been tested for 18 F production. As a proton accelerator, the target systems and nuclear reactions are similar to the ones used in PET cyclotrons. (author)

  14. Applications of Particle Accelerators in Medical Physics

    OpenAIRE

    Cuttone, G

    2008-01-01

    Particle accelerators are often associated to high energy or nuclear physics. As well pointed out in literature [1] if we kindly analyse the number of installation worldwide we can easily note that about 50% is mainly devoted to medical applications (radiotherapy, medical radioisotopes production, biomedical research). Particle accelerators are also playing an important indirect role considering the improvement of the technical features of medical diagnostic. In fact the use of radionuclide f...

  15. MO-FG-BRC-00: Joint AAPM-ESTRO Symposium: Advances in Experimental Medical Physics

    International Nuclear Information System (INIS)

    2016-01-01

    Experimental research in medical physics has expanded the limits of our knowledge and provided novel imaging and therapy technologies for patients around the world. However, experimental efforts are challenging due to constraints in funding, space, time and other forms of institutional support. In this joint ESTRO-AAPM symposium, four exciting experimental projects from four different countries are highlighted. Each project is focused on a different aspect of radiation therapy. From the USA, we will hear about a new linear accelerator concept for more compact and efficient therapy devices. From Canada, we will learn about novel linear accelerator target design and the implications for imaging and therapy. From France, we will discover a mature translational effort to incorporate theranostic nanoparticles in MR-guided radiation therapy. From Germany, we will find out about a novel in-treatment imaging modality for particle therapy. These examples of high impact, experimental medical physics research are representative of the diversity of such efforts that are on-going around the globe. J. Robar, Research is supported through collaboration with Varian Medical Systems and Brainlab AGD. Westerly, This work is supported by the Department of Radiation Oncology at the University of Colorado School of Medicine. COI: NONEK. Parodi, Part of the presented work is supported by the DFG (German Research Foundation) Cluster of Excellence MAP (Munich-Centre for Advanced Photonics) and has been carried out in collaboration with IBA.

  16. Advances in the physics of radiation oncology - 50 years of contributions by US Medical Physicists

    International Nuclear Information System (INIS)

    Suntharalingam, N.

    2008-01-01

    Medical Physicists have a long standing record in the advancement of the discipline of Radiation Oncology, not only in the United States but world-wide, going back to the pre-world war II era. In the United States the contributions of Failla and Quimby, first at Memorial Hospital and then at Columbia University in New York, laid the foundation for the Profession of Medical Physics in the US. Radiation Therapy first used low and high kilovoltage machines for external beam therapy. Radium (Parker) and radon seeds (Quimby) were used for brachytherapy. Subsequently, clinical Van-de-Graaff machines (Trump and Wright) and the Betatron (Kerst, Adams and Skaggs) provided the required photon beams and also made available clinically useful electron beams. The work of John Laughlin, Larry Lanzl, Jacques Ovadia together with Gail Adams and Lester Skaggs, needs to be recognized for their pioneering efforts. With the introduction of Cobalt-60 Teletherapy (Harold Johns and the Canadian Group, Gilbert Fletcher and the MD Anderson Group) and Linear Accelerators (Henry Kaplan and the Stanford Group, and Varian), in the late 1950s ∼ 1960, there was even a greater need for the strong participation of medical physicists, as a useful technical resource to the physicians

  17. Evaluation of the photon monitor backscatter in medical electron accelerators

    International Nuclear Information System (INIS)

    Zrenner, M.; Krieger, H.

    1999-01-01

    Background: Modern linear accelerators permit the use of irregular fields due to their flexible collimator systems with separately movable jaws or multileaf collimators. When using such irregular fields in the clinical practice output factors have to be corrected for enhanced backscatter to the dose monitor as compared with the conventional block shieldings. Methods: A method is presented to detect the monitor backscatter contributions to the output factor for irregular field settings. Results: The monitor backscatter factors have been measured using a telescopic device for 2 different treatment head geometries (Varian Clinac 2100C/D, General Electric Saturne 15) and for 3 photon radiation qualities (nominal energies X6, X18, X12). A method is introduced to calculate the monitor backscatter for arbitrary irregular treatment fields from the experimental data for square or rectangular fields. Conclusions: Besides the corrections for changes in phantom scatter and changes in the aperture, corrections for monitor backscatter have to be taken into account in many clinical cases. They can contribute up to more than 10% compared with the monitor values for free regular fields. (orig.) [de

  18. Cognitive Medical Multiagent Systems

    OpenAIRE

    Barna Iantovics

    2010-01-01

    The development of efficient and flexible agent-based medical diagnosis systems represents a recent research direction. Medical multiagent systems may improve the efficiency of traditionally developed medical computational systems, like the medical expert systems. In our previous researches, a novel cooperative medical diagnosis multiagent system called CMDS (Contract Net Based Medical Diagnosis System) was proposed. CMDS system can solve flexibly a large variety of medical diagnosis problems...

  19. Implementing and Integrating a Clinically-Driven Electronic Medical Record (EMR for Radiation Oncology in a Large Medical Enterprise

    Directory of Open Access Journals (Sweden)

    John Paxton Kirkpatrick

    2013-04-01

    Full Text Available Purpose/Objective: While our department is heavily invested in computer-based treatment planning, we historically relied on paper-based charts for management of Radiation Oncology patients. In early 2009, we initiated the process of conversion to an electronic medical record (EMR eliminating the need for paper charts. Key goals included the ability to readily access information wherever and whenever needed, without compromising safety, treatment quality, confidentiality or productivity.Methodology: In February, 2009, we formed a multi-disciplinary team of Radiation Oncology physicians, nurses, therapists, administrators, physicists/dosimetrists, and information technology (IT specialists, along with staff from the Duke Health System IT department. The team identified all existing processes and associated information/reports, established the framework for the EMR system and generated, tested and implemented specific EMR processes.Results: Two broad classes of information were identified: information which must be readily accessed by anyone in the health system versus that used solely within the Radiation Oncology department. Examples of the former are consultation reports, weekly treatment check notes and treatment summaries; the latter includes treatment plans, daily therapy records and quality assurance reports. To manage the former, we utilized the enterprise-wide system , which required an intensive effort to design and implement procedures to export information from Radiation Oncology into that system. To manage "Radiation Oncology" data, we used our existing system (ARIA, Varian Medical Systems. The ability to access both systems simultaneously from a single workstation (WS was essential, requiring new WS and modified software. As of January, 2010, all new treatments were managed solely with an EMR. We find that an EMR makes information more widely accessible and does not compromise patient safety, treatment quality or confidentiality

  20. Energy and energy policy

    International Nuclear Information System (INIS)

    Clerici, A.

    2007-01-01

    Energy has taken with his reflections on the environment, the geopolitical aspects and its pervasive use in all activities a crucial role for sustainable development of our planet. The energy in the future will be increasingly a global problem [it

  1. U Y 108 standard regulation standard of the radiological safety for medical and dental radiodiagnostic practice: approve for the Industry Energy and Mining Ministry 28/6/2002 Resolution

    International Nuclear Information System (INIS)

    2002-01-01

    Guarantee and effective control in Medical and Dental Radiodiagnostic for avoid unnecessary exposition in public and workers as well limit the possibility of accidents and the patient dose was the minimal necessary

  2. Radiotracers for medical applications

    International Nuclear Information System (INIS)

    Rayudu, G.A.S.

    1983-01-01

    This book discusses the medical applications of radiotracers. Diagnostic uses and pharmacokinetics of isotopes and radiopharmaceuticals is emphasized. The volume one covers the following topics: Radiohalogenated compounds, including radioiodine; Tc-labeled compounds; and in-house prepared radiopharmaceuticals. The charge particle range vs. energy in every element is tabulated for protons for cyclotrons users. Discussions are also provided on nonimaging radiotracer methods; /sup 11/C, /sup 13/N, /sup 15/O, /sup 67/Ga. /sup 111/In, /sup 75/Se, /sup 123m/Te compounds; radioactive noble gases; and miscellaneous radiotracers for imaging. Vol. II: Pertinent nuclear science data such as radiation dosimetry, radionuclide production modes, radionuclides for therapy, human experimentation regulations and consent forms, and radiotracer laboratory designs are presented. 272 pp., 7 x 10, 1983, ISBN-0-8493-6016-1

  3. Thermoluminescence in medical dosimetry

    International Nuclear Information System (INIS)

    Rivera, T.

    2011-10-01

    The dosimetry by thermoluminescence (Tl) is applied in the entire world for the dosimetry of ionizing radiations specially to personal and medical dosimetry. This dosimetry method has been very interesting for measures in vivo because the Tl dosimeters have the advantage of being very sensitive in a very small volume and they are also equivalent to tissue and they do not need additional accessories (for example, cable, electrometer, etc.) The main characteristics of the diverse Tl materials to be used in the radiation measures and practical applications are: the Tl curve, the share homogeneity, the signal stability after the irradiation, precision and exactitude, the response in function with the dose and the energy influence. In this work a brief summary of the advances of the radiations dosimetry is presented by means of the thermally stimulated luminescence and its application to the dosimetry in radiotherapy. (Author)

  4. Implantable Medical Devices

    Science.gov (United States)

    ... Artery Disease Venous Thromboembolism Aortic Aneurysm More Implantable Medical Devices Updated:Sep 16,2016 For Rhythm Control ... a Heart Attack Introduction Medications Surgical Procedures Implantable Medical Devices • Life After a Heart Attack • Heart Attack ...

  5. Medical alert bracelet (image)

    Science.gov (United States)

    People with diabetes should always wear a medical alert bracelet or necklace that emergency medical workers will be able to find. Medical identification products can help ensure proper treatment in an ...

  6. Asthma Medications and Pregnancy

    Science.gov (United States)

    ... Asthma Associated Conditions Asthma & Pregnancy Asthma & Pregnancy: Medications Asthma & Pregnancy: Medications Make an Appointment Refer a Patient ... make sure you are using it correctly. Other Asthma Related Medication Treatment Annual influenza vaccine (flu shot) ...

  7. Medications (for IBS)

    Medline Plus

    Full Text Available ... Agents Antidiarrheal Agents Antidepressant Medications Newer IBS Medications Probiotics and Antibiotics Pharmacologic, or drug, therapy is best ... Agents Antidiarrheal Agents Antidepressant Medications Newer IBS ... Antibiotics Psychological Treatments Understanding Stress Cognitive Behavioral ...

  8. Medication/Drug Allergy

    Science.gov (United States)

    ... Training Home Conditions Medication/Drug Allergy Medication/Drug Allergy Make an Appointment Find a Doctor Ask a ... risk for adverse reactions to medications. Facts about Allergies The tendency to develop allergies may be inherited. ...

  9. WE-AB-202-08: Feasibility of Single-Inhalation/Single-Energy Xenon CT for High-Resolution Imaging of Regional Lung Ventilation in Humans

    International Nuclear Information System (INIS)

    Pinkham, D; Schueler, E; Diehn, M; Mittra, E; Loo, B; Maxim, P; Negahdar, M; Yamamoto, T

    2016-01-01

    quantify regional lung ventilation volumetrically with high resolution using widely accessible radiologic equipment. Bill Loo and Peter Maxim are founders of TibaRay, Inc. Bill Loo is also a board member. Bill Loo and Peter Maxim have received research grants from Varian Medical Systems, Inc. and RaySearch Laboratory

  10. WE-AB-202-08: Feasibility of Single-Inhalation/Single-Energy Xenon CT for High-Resolution Imaging of Regional Lung Ventilation in Humans

    Energy Technology Data Exchange (ETDEWEB)

    Pinkham, D; Schueler, E; Diehn, M; Mittra, E; Loo, B; Maxim, P [Stanford University School of Medicine, Palo Alto, California (United States); Negahdar, M [IBM Research Center, San Jose, California (United States); Yamamoto, T [University of California Davis Medical Center, Sacramento, CA (United States)

    2016-06-15

    quantify regional lung ventilation volumetrically with high resolution using widely accessible radiologic equipment. Bill Loo and Peter Maxim are founders of TibaRay, Inc. Bill Loo is also a board member. Bill Loo and Peter Maxim have received research grants from Varian Medical Systems, Inc. and RaySearch Laboratory.

  11. Wavelets in medical imaging

    International Nuclear Information System (INIS)

    Zahra, Noor e; Sevindir, Huliya A.; Aslan, Zafar; Siddiqi, A. H.

    2012-01-01

    The aim of this study is to provide emerging applications of wavelet methods to medical signals and images, such as electrocardiogram, electroencephalogram, functional magnetic resonance imaging, computer tomography, X-ray and mammography. Interpretation of these signals and images are quite important. Nowadays wavelet methods have a significant impact on the science of medical imaging and the diagnosis of disease and screening protocols. Based on our initial investigations, future directions include neurosurgical planning and improved assessment of risk for individual patients, improved assessment and strategies for the treatment of chronic pain, improved seizure localization, and improved understanding of the physiology of neurological disorders. We look ahead to these and other emerging applications as the benefits of this technology become incorporated into current and future patient care. In this chapter by applying Fourier transform and wavelet transform, analysis and denoising of one of the important biomedical signals like EEG is carried out. The presence of rhythm, template matching, and correlation is discussed by various method. Energy of EEG signal is used to detect seizure in an epileptic patient. We have also performed denoising of EEG signals by SWT.

  12. Wavelets in medical imaging

    Energy Technology Data Exchange (ETDEWEB)

    Zahra, Noor e; Sevindir, Huliya A.; Aslan, Zafar; Siddiqi, A. H. [Sharda University, SET, Department of Electronics and Communication, Knowledge Park 3rd, Gr. Noida (India); University of Kocaeli, Department of Mathematics, 41380 Kocaeli (Turkey); Istanbul Aydin University, Department of Computer Engineering, 34295 Istanbul (Turkey); Sharda University, SET, Department of Mathematics, 32-34 Knowledge Park 3rd, Greater Noida (India)

    2012-07-17

    The aim of this study is to provide emerging applications of wavelet methods to medical signals and images, such as electrocardiogram, electroencephalogram, functional magnetic resonance imaging, computer tomography, X-ray and mammography. Interpretation of these signals and images are quite important. Nowadays wavelet methods have a significant impact on the science of medical imaging and the diagnosis of disease and screening protocols. Based on our initial investigations, future directions include neurosurgical planning and improved assessment of risk for individual patients, improved assessment and strategies for the treatment of chronic pain, improved seizure localization, and improved understanding of the physiology of neurological disorders. We look ahead to these and other emerging applications as the benefits of this technology become incorporated into current and future patient care. In this chapter by applying Fourier transform and wavelet transform, analysis and denoising of one of the important biomedical signals like EEG is carried out. The presence of rhythm, template matching, and correlation is discussed by various method. Energy of EEG signal is used to detect seizure in an epileptic patient. We have also performed denoising of EEG signals by SWT.

  13. Photo-medical valley. 'Photo medical research center'

    International Nuclear Information System (INIS)

    Kawanishi, Shunichi; Daido, Hiroyuki; Tajima, Toshiki

    2008-01-01

    To develop a much more compact cancer diagnosis and therapeutic instrument using high intensity laser technology, Japan Atomic Energy Agency (JAEA) has successfully proposed this novel effort to the Ministry of Education, Culture, Sports, Science and Technology (MEXT) program as the creation of a 'photo-medical industrial valley' base in 2007 fiscal year. In this report, a new laser techniques to drive controlled ion beams is described. It is very important approach to realize a laser-driven ion accelerator. (author)

  14. Medications (for IBS)

    Medline Plus

    Full Text Available ... Antidepressant Medications Newer IBS Medications Probiotics and Antibiotics Psychological Treatments Understanding Stress Cognitive Behavioral Therapy Relaxation Techniques for IBS Take Part in Online ...

  15. Medications (for IBS)

    Medline Plus

    Full Text Available ... Agents Antidepressant Medications Newer IBS Medications Probiotics and Antibiotics Psychological Treatments Understanding Stress Cognitive Behavioral Therapy Relaxation Techniques for ...

  16. Cognitive Medical Multiagent Systems

    Directory of Open Access Journals (Sweden)

    Barna Iantovics

    2010-01-01

    Full Text Available The development of efficient and flexible agent-based medical diagnosis systems represents a recent research direction. Medical multiagent systems may improve the efficiency of traditionally developed medical computational systems, like the medical expert systems. In our previous researches, a novel cooperative medical diagnosis multiagent system called CMDS (Contract Net Based Medical Diagnosis System was proposed. CMDS system can solve flexibly a large variety of medical diagnosis problems. This paper analyses the increased intelligence of the CMDS system, which motivates its use for different medical problem’s solving.

  17. Medications (for IBS)

    Medline Plus

    Full Text Available ... Anthony J. Lembo, MD, Instructor of Medicine, Harvard Medical School; Division of Gastroenterology, Beth Israel Deaconess Medical Center, Boston, MA. Last modified on February 23, ...

  18. Medical cyclotron: why, where, how

    International Nuclear Information System (INIS)

    Scheer, Kurt; Comar, Dominique; Kellershohn, Claude

    1976-01-01

    Cyclotrons for medical purposes are particularly useful for the production of radioactive isotopes of elements normally constituting organic matter ( 15 O, 13 N, 11 C). The short half-life and positron emission of those elements are of great interest in medical diagnosis. Many others carrier-free radioisotopes can be produced by cyclotrons. Three categories of cyclotrons are mentioned. Desk top cyclotron only adapted to the production of short-lived radioisotopes in a hospital; low energy and average energy cyclotrons which require well-entrained personnel for their operation and are best adapted to the production of radioelements on a regional or even national scale. Examples relative to the interest of short-lived radioisotopes in lung and brain investigations and tumor detection are given

  19. Medical physics practice and training in Ghana.

    Science.gov (United States)

    Amuasi, John H; Kyere, Augustine K; Schandorf, Cyril; Fletcher, John J; Boadu, Mary; Addison, Eric K; Hasford, Francis; Sosu, Edem K; Sackey, Theophilus A; Tagoe, Samuel N A; Inkoom, Stephen; Serfor-Armah, Yaw

    2016-06-01

    Medical physics has been an indispensable and strategic stakeholder in the delivery of radiological services to the healthcare system of Ghana. The practice has immensely supported radiation oncology and medical imaging facilities over the years, while the locally established training programme continues to produce human resource to feed these facilities. The training programme has grown to receive students from other African countries in addition to local students. Ghana has been recognised by the International Atomic Energy Agency as Regional Designated Centre for Academic Training of Medical Physicists in Africa. The Ghana Society for Medical Physics collaborates with the School of Nuclear and Allied Sciences of the University of Ghana to ensure that training offered to medical physicists meet international standards, making them clinically qualified. The Society has also worked together with other bodies for the passage of the Health Profession's Regulatory Bodies Act, giving legal backing to the practice of medical physics and other allied health professions in Ghana. The country has participated in a number of International Atomic Energy Agency's projects on medical physics and has benefited from its training courses, fellowships and workshops, as well as those of other agencies such as International Organization for Medical Physics. This has placed Ghana's medical physicists in good position to practice competently and improve healthcare. Copyright © 2016 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.

  20. Planetary method to measure the neutrons spectrum in lineal accelerators of medical use; Metodo planetario para medir el espectro de neutrones en aceleradores lineales de uso medico

    Energy Technology Data Exchange (ETDEWEB)

    Vega C, H. R. [Universidad Autonoma de Zacatecas, Unidad Academica de Estudios Nucleares, Cipres No. 10, Fracc. La Penuela, 98068 Zacatecas (Mexico); Benites R, J. L., E-mail: fermineutron@yahoo.com [Centro Estatal de Cancerologia de Nayarit, Servicio de Seguridad Radiologica, Calzada de la Cruz 118 Sur, 63000 Tepic, Nayarit (Mexico)

    2014-08-15

    A novel procedure to measure the neutrons spectrum originated in a lineal accelerator of medical use has been developed. The method uses a passive spectrometer of Bonner spheres. The main advantage of the method is that only requires of a single shot of the accelerator. When this is used around a lineal accelerator is necessary to operate it under the same conditions so many times like the spheres that contain the spectrometer, activity that consumes enough time. The developed procedure consists on situating all the spheres of the spectrometer at the same time and to realize the reading making a single shot. With this method the photo neutrons spectrum produced by a lineal accelerator Varian ix of 15 MV to 100 cm of the isocenter was determined, with the spectrum is determined the total flow and the ambient dose equivalent. (Author)

  1. Dosimetry of the energy of the electrons beam and virtual distance of the source of a lineal accelerator

    International Nuclear Information System (INIS)

    Gonzales, A.; Garcia, B.; Ramirez, J.; Marquina, J.

    2014-08-01

    The objectives of this work were to characterize, to gauge the energy of a electrons beam of 12 MeV and to find the virtual distance of the source for a lineal accelerator Trilogy-Varian. For the characterization, calibration and to find the virtual distance of the source of a lineal accelerator Trilogy-Varian, a water phantom was used (cylindrical Cuba 3-D) of Sun-Nuclear. The following values were found: R 50.ion = 4, 95 g/cm 2 , R 50 = 5, 04 g/cm 2 , Z ref = 2,92 g/cm 2 , Z max = 2, 60 g/cm 2 . In the calibration was found D W,Q (Z max ) = 1, 0015 c Gy/Um. In the profile In-plane was measured a symmetry and flatness of 1, 9% and 1, 6% respectively. In the profile Cross-plane a symmetry was measured and flatness of 1, 9% and 1, 3% respectively. The virtual distance regarding the source was of DFS (virtual) =105,81 cm. The electrons beam of 12 MeV was characterized and gauged satisfactorily, were carried out the In-plane and Cross-plane profiles, obtaining all the parameters inside the acceptance limit. The virtual distance of the source was of 105,81 cm. (Author)

  2. Energy: nuclear energy

    International Nuclear Information System (INIS)

    Lung, M.

    2000-11-01

    Convinced that the nuclear energy will be the cleaner, safer, more economical and more respectful of the environment energy of the future, the author preconizes to study the way it can be implemented, to continue to improve its production, to understand its virtues and to better inform the public. He develops this opinion in the presentation of the principal characteristics of the nuclear energy: technology, radioactive wastes, radiation protection, the plutonium, the nuclear accidents, the proliferation risks, the economics and nuclear energy and competitiveness, development and sustainability. (A.L.B.)

  3. Role of accelerator science and technology in medical science

    International Nuclear Information System (INIS)

    Uesaka, Mitsuru

    2006-01-01

    Updated status of compact and advanced-compact medical accelerator development is reviewed. In their applications, medical physics and medical physicist are necessary. Their educational programs have started in several universities and institutes. As one important new trend on life-science, the research on the synergy of DDS (Drug Delivery System) and physical energies are proposed. (author)

  4. Port Harcourt Medical Journal

    African Journals Online (AJOL)

    Port Harcourt Medical Journal's objectives are to disseminate medical information from the College of Health Sciences, University of Port Harcourt and the rest of the national and international medical community; act as a medium for the articulation of research and findings from same as well as proceedings of medical ...

  5. Compounds Labelled with Low-Energy Gamma-Ray Emitters for Medical Isotope Scanning; Gammagraphie au Moyen de Composes Marques avec des Emetteurs Gamma de Faible Energie; Soedineniya, ispol'zuemye pri meditsinskom izotopnom skennirovanii, mechennye s pomoshch'yu gamma-izluchatelej nizkoj ehnergii; Compuestos Marcados con Emisores Gamma de Baja Energia para la Exploracion Medica Mediante Isotopos

    Energy Technology Data Exchange (ETDEWEB)

    Scheer, K. E.; Zum Winkel, K.; Georgi, M. [Czerny-Krankenhaus der Universitat Heidelberg, Federal Republic of Germany (Germany)

    1964-10-15

    Low-energy gamma emitters have a special merit for medical scintillation scanning for the following reasons: (1) The lead shielding of the collimators is much more effective. Multiple focusing thin-walled hole collimators can therefore be used, making a higher geometrical resolution possible and, therefore, the detection of smaller lesions. (2) The absorption of the radiation within the body tissue limits the depth of visibility of lesions. In extended organs like the liver, the superposition of radiation originating from the back of the organ is avoided. This allows a better detection of more superficial lesions. The most important low-energy gamma-emitting nuclide is I{sup 125}. For thyroid scanning, it is used in the form of iodide. A suitable compound for liver scanning is I{sup 125}-labelled Rose Bengal. An alternative compound is I{sup 125} -CAI (heat denatured albumin). For kidney scanning I{sup 125}-Hippuran was found to be suitable when injected intramuscularly with hyaluronidase to ensure a uniform level of radioactivity in the kidneys. Another useful low-energy gamma-emitting nuclide for medical scanning is Hg{sup 197} which may be used as chloride for kidney and spleen scanning. Special precautions must be taken to avoid overlying of kidney and spleen. A higher quality scan is obtained with Hg{sup 197}-labelled Neohydrin. This compound is also useful for brain-tumour localization. Typical scans of thyroid, liver, spleen, kidney and brain tumours obtained with low-energy gamma emitters and conventional nuclides and compounds are presented and the merits of the former are discussed. (author) [French] Les emetteurs gamma de faible energie presentent un interet particulier en gammagraphie, pour les raisons suivantes: 1. L'ecran en plomb des collimateurs est beaucoup plus efficace. On peut donc utiliser des collimateurs a focalisation a canaux multiples, et a parois minces, qui permettent d'avoir un excellent pouvoir de resolution et, par consequent, de

  6. STS-3 medical report

    Science.gov (United States)

    Pool, S. L. (Editor); Johnson, P. C., Jr. (Editor); Mason, J. A. (Editor)

    1982-01-01

    The medical operations report for STS-3, which includes a review of the health of the crew before, during, and immediately after the third Shuttle orbital flight is presented. Areas reviewed include: health evaluation, medical debriefing of crewmembers, health stabilization program, medical training, medical 'kit' carried in flight, tests and countermeasures for space motion sickness, cardiovascular profile, biochemistry and endocrinology results, hematology and immunology analyses, medical microbiology, food and nutrition, potable water, shuttle toxicology, radiological health, and cabin acoustic noise. Environmental effects of shuttle launch and landing medical information management, and management, planning, and implementation of the medical program are also dicussed.

  7. Machine medical ethics

    CERN Document Server

    Pontier, Matthijs

    2015-01-01

    The essays in this book, written by researchers from both humanities and sciences, describe various theoretical and experimental approaches to adding medical ethics to a machine in medical settings. Medical machines are in close proximity with human beings, and getting closer: with patients who are in vulnerable states of health, who have disabilities of various kinds, with the very young or very old, and with medical professionals. In such contexts, machines are undertaking important medical tasks that require emotional sensitivity, knowledge of medical codes, human dignity, and privacy. As machine technology advances, ethical concerns become more urgent: should medical machines be programmed to follow a code of medical ethics? What theory or theories should constrain medical machine conduct? What design features are required? Should machines share responsibility with humans for the ethical consequences of medical actions? How ought clinical relationships involving machines to be modeled? Is a capacity for e...

  8. Medicalization, markets and consumers.

    Science.gov (United States)

    Conrad, Peter; Leiter, Valerie

    2004-01-01

    This paper examines the impact of changes in the medical marketplace on medicalization in U.S. society. Using four cases (Viagra, Paxil, human growth hormone and in vitro fertilization), we focus on two aspects of the changing medical marketplace: the role of direct-to-consumer advertising of prescription drugs and the emergence of private medical markets. We demonstrate how consumers and pharmaceutical corporations contribute to medicalization, with physicians, insurance coverage, and changes in regulatory practices playing facilitating roles. In some cases, insurers attempt to counteract medicalization by restricting access. We distinguish mediated and private medical markets, each characterized by differing relationships with corporations, insurers, consumers, and physicians. In the changing medical environment, with medical markets as intervening factors, corporations and insurers are becoming more significant determinants in the medicalization process.

  9. Low‐cost flexible thin‐film detector for medical dosimetry applications

    Science.gov (United States)

    Abkai, C.; Han, Z.; Shulevich, Y.; Menichelli, D.; Hesser, J.

    2014-01-01

    The purpose of this study is to characterize dosimetric properties of thin film photovoltaic sensors as a platform for development of prototype dose verification equipment in radiotherapy. Towards this goal, flexible thin‐film sensors of dose with embedded data acquisition electronics and wireless data transmission are prototyped and tested in kV and MV photon beams. Fundamental dosimetric properties are determined in view of a specific application to dose verification in multiple planes or curved surfaces inside a phantom. Uniqueness of the new thin‐film sensors consists in their mechanical properties, low‐power operation, and low‐cost. They are thinner and more flexible than dosimetric films. In principle, each thin‐film sensor can be fabricated in any size (mm2 – cm2 areas) and shape. Individual sensors can be put together in an array of sensors spreading over large areas and yet being light. Photovoltaic mode of charge collection (of electrons and holes) does not require external electric field applied to the sensor, and this implies simplicity of data acquisition electronics and low power operation. The prototype device use for testing consists of several thin film dose sensors, each of about 1.5 cm×5 cm area, connected to simple readout electronics. Sensitivity of the sensors is determined per unit area and compared to EPID sensitivity, as well as other standard photodiodes. Each sensor independently measures dose and is based on commercially available flexible thin‐film aSi photodiodes. Readout electronics consists of an ultra low‐power microcontroller, radio frequency transmitter, and a low‐noise amplification circuit implemented on a flexible printed circuit board. Detector output is digitized and transmitted wirelessly to an external host computer where it is integrated and processed. A megavoltage medical linear accelerator (Varian Tx) equipped with kilovoltage online imaging system and a Cobalt source are use to irradiate

  10. Low-cost flexible thin-film detector for medical dosimetry applications.

    Science.gov (United States)

    Zygmanski, P; Abkai, C; Han, Z; Shulevich, Y; Menichelli, D; Hesser, J

    2014-03-06

    The purpose of this study is to characterize dosimetric properties of thin film photovoltaic sensors as a platform for development of prototype dose verification equipment in radiotherapy. Towards this goal, flexible thin-film sensors of dose with embedded data acquisition electronics and wireless data transmission are prototyped and tested in kV and MV photon beams. Fundamental dosimetric properties are determined in view of a specific application to dose verification in multiple planes or curved surfaces inside a phantom. Uniqueness of the new thin-film sensors consists in their mechanical properties, low-power operation, and low-cost. They are thinner and more flexible than dosimetric films. In principle, each thin-film sensor can be fabricated in any size (mm² - cm² areas) and shape. Individual sensors can be put together in an array of sensors spreading over large areas and yet being light. Photovoltaic mode of charge collection (of electrons and holes) does not require external electric field applied to the sensor, and this implies simplicity of data acquisition electronics and low power operation. The prototype device used for testing consists of several thin film dose sensors, each of about 1.5 cm × 5 cm area, connected to simple readout electronics. Sensitivity of the sensors is determined per unit area and compared to EPID sensitivity, as well as other standard photodiodes. Each sensor independently measures dose and is based on commercially available flexible thin-film aSi photodiodes. Readout electronics consists of an ultra low-power microcontroller, radio frequency transmitter, and a low-noise amplification circuit implemented on a flexible printed circuit board. Detector output is digitized and transmitted wirelessly to an external host computer where it is integrated and processed. A megavoltage medical linear accelerator (Varian Tx) equipped with kilovoltage online imaging system and a Cobalt source are used to irradiate different thin

  11. Medical and sanitation activity of the Institute of Nuclear Safety and Protection of the French Commissariat a l'energie atomic after the Chernobyl' accident within the Soviet-French cooperation frameworks

    International Nuclear Information System (INIS)

    Nenot, J.C.; Pauli, E.

    1990-01-01

    The Institute of Nuclear Safety and Protection intends to help in surveillance of the population subjected to radiation effects, environmental monitoring around the Chernobyl' NPP, organization of works and observations dealing with radioecology. The program of two-side French-Soviet actions including assistance for physicians in professional patient treatments, medical assistant for children and families evacuated to Kiev

  12. TU-H-BRC-03: Evaluation of Very High-Energy Electron (VHEE) Beams in Comparison to VMAT and PBS Treatment Plans

    Energy Technology Data Exchange (ETDEWEB)

    Schueler, E; Loo, B; Maxim, P [Stanford University School of Medicine, Palo Alto, California (United States); Eriksson, K; Hynning, E [RaySearch Laboratories, Stockholm (Sweden)

    2016-06-15

    Purpose: The aim of this study was to evaluate the performance of very high-energy electron (VHEE) beams in comparison to clinically delivered treatment plans generated with volumetric modulated arc therapy (VMAT) and proton pencil beam scanning (PBS) technology. Methods: Three clinical cases were selected (prostate, lung, and pediatric CNS). The VHEE plans were calculated in the Monte Carlo EGSnrc code and pencil beam doses were calculated using the DOSxyznrc MC code for 100 and 200 MeV beams. Treatment plans with VHEE, VMAT, and PBS were optimized in a research version of RayStation using an in house build script in order to minimize operator bias between the different techniques. Results: For the prostate cancer case, the PBS plan showed lower mean organ at risk (OAR) doses compared to the other modalities. An exception was the femoral heads, due to the lateral beam arrangements. The VMAT plan showed lower mean doses to the rectum and the bladder compared to the 100 MeV VHEE plan. The lung cancer case showed minor differences between the three modalities. However, the PBS plan showed a lower contralateral lung dose. The pediatric CNS case showed a better conformity and lower spinal cord dose for the 100 MeV VHEE plan. For all cases, the 200 MeV VHEE plans were found to be similar to or better than the 100 MeV VHEE plans. Conclusion: The present study showed that VHEE plans are similar or superior to VMAT plans with reduced mean OAR dose and increased target conformity for a variety of clinical cases. With increased VHEE energy, better conformity and even higher reductions in mean OAR doses can be achieved. Funding: DoD, Award#:W81XWH-13-1-0165, Weston Havens Foundation, Bio-X (Stanford University), the Office of the Dean of the Medical School, the Office of the Provost (Stanford University), and the Swedish Childhood Cancer Foundation. BL and PM are founders of TibaRay,Inc. BL and PM have received research grants from Varian and RaySearch Laboratory.

  13. Future energy, exotic energy

    Energy Technology Data Exchange (ETDEWEB)

    Dumon, R

    1974-01-01

    The Detroit Energy Conference has highlighted the declining oil reserves, estimated worldwide at 95 billion tons vs. an annual rate of consumption of over 3 billion tons. The present problem is one of price; also, petroleum seems too valuable to be simply burned. New sources must come into action before 1985. The most abundant is coal, with 600 billion tons of easily recoverable reserves; then comes oil shale with a potential of 400 billion tons of oil. Exploitation at the rate of 55 go 140 million tons/yr is planned in the U.S. after 1985. More exotic and impossible to estimate quantitatively are such sources as wind, tides, and the thermal energy of the oceans--these are probably far in the future. The same is true of solar and geothermal energy in large amounts. The only other realistic energy source is nuclear energy: the European Economic Community looks forward to covering 60% of its energy needs from nuclear energy in the year 2000. Even today, from 400 mw upward, a nuclear generating plant is more economical than a fossil fueled one. Conservation will become the byword, and profound changes in society are to be expected.

  14. Medical History: Compiling Your Medical Family Tree

    Science.gov (United States)

    ... are missing. If you're adopted, ask your adoptive parents if they received any medical information about your biological parents at the time of your adoption. Adoption agencies also might have family medical information on file. If you were adopted ...

  15. Nuclear energy and renewable energies

    International Nuclear Information System (INIS)

    1994-01-01

    The nuclear energy and the renewable energies namely: solar energy, wind energy, geothermal energy and biomass are complementary. They are not polluting and they are expected to develop in the future to replace the fossil fuels

  16. Medical service plans in academic medical centers.

    Science.gov (United States)

    Siegel, B

    1978-10-01

    Medical service plans are of major importance to academic medical centers and are becoming increasingly so each year as evidenced by growing dependence of medical schools on resulting funds. How these funds are generated and used varies among schools. The procedures may affect the governance of the institution, modifying the authority of the central administration or the clinical departments. Recent developments in federal legislation, such as health maintenance organizations and amendments (Section 227) to the Social Security Act, and the future development of national health insurance will certainly have an effect on how academic medical centers organize their clinical activities. How successfully various medical schools deal with the dynamic problem may well determine their future survival.

  17. Validation of Varian's AAA algorithm with focus on lung treatments

    International Nuclear Information System (INIS)

    Roende, Heidi S.; Hoffmann, Lone

    2009-01-01

    The objective of this study was to examine the accuracy of the Anisotropic Analytical Algorithm (AAA). A variety of different field configurations in homogeneous and in inhomogeneous media (lung geometry) was tested for the AAA algorithm. It was also tested against the present Pencil Beam Convolution (PBC) algorithm. Materials and methods. Two dimensional (2D) dose distributions were measured for a variety of different field configurations in solid water with a 2D array of ion chambers. The dose distributions of patient specific treatment plans in selected transversal slices were measured in a Thorax lung phantom with Gafchromic dosimetry films. A Farmer ion chamber was used to check point doses in the Thorax phantom. The 2D dose distributions were evaluated with a gamma criterion of 3% in dose and 3 mm distance to agreement (DTA) for the 2D array measurements and for the film measurements. Results. For AAA, all fields tested in homogeneous media fulfilled the criterion, except asymmetric fields with wedges and intensity modulated plans where deviations of 5 and 4%, respectively, were seen. Overall, the measured and calculated 2D dose distributions for AAA in the Thorax phantom showed good agreement - both for 6 and 15 MV photons. More than 80% of the points in the high dose regions met the gamma criterion, though it failed at low doses and at gradients. For the PBC algorithm only 30-70% of the points met the gamma criterion. Conclusion. The AAA algorithm has been shown to be superior to the PBC algorithm in heterogeneous media, especially for 15 MV. For most treatment plans the deviations in the lung and the mediastinum regions are below 3%. However, the algorithm may underestimate the dose to the spinal cord by up to 7%

  18. Analisis Throughput Varian TCP Pada Model Jaringan WiMAX

    Directory of Open Access Journals (Sweden)

    Medi Taruk

    2016-07-01

    Full Text Available Transmission Control Protocol (TCP is a protocol that works at the transport layer of the OSI model. TCP was originally designed more destined for a wired network. However, to meet the need for the development of a very fast network technology based on the needs of the use by the user, it needs further development to the use of TCP on wireless devices. One implementation of a wireless network based on Worldwide Interoperability for Microwave Access (WiMAX network is a model that offers a variety advantage, particularly in terms of access speed. In this case, use NS-2 to see throughput at TCP variants tested, namely TCP-Tahoe, TCP-Reno, TCP-Vegas, and TCP-SACK over WiMAX network model, with few observations scenarios. The first is a look at each of these variants throughput of TCP when only one particular variant of the work in the network. Second observe all variants of TCP throughput at the same time and have the equivalent QoS, but with the possibility of a small congestion based on the capacity of the link is made sufficient. Third observed throughput with multi congestion. In WiMAX network has scheduling services are UGS, rtPS and ertPS using UDP protocol and nrtPS and BE using the TCP Protocol. By using the software network simulator (NS-2 to obtain performance comparison TCP protocol-based services on the WiMAX network with QoS parameters are throughput, packet loss, fairness and time delay.

  19. CBH1 homologs and varian CBH1 cellulase

    Energy Technology Data Exchange (ETDEWEB)

    Goedegebuur, Frits; Gualfetti, Peter; Mitchinson, Colin; Neefe, Paulien

    2014-07-01

    Disclosed are a number of homologs and variants of Hypocrea jecorina Cel7A (formerly Trichoderma reesei cellobiohydrolase I or CBH1), nucleic acids encoding the same and methods for producing the same. The homologs and variant cellulases have the amino acid sequence of a glycosyl hydrolase of family 7A wherein one or more amino acid residues are substituted and/or deleted.

  20. Energy crisis

    International Nuclear Information System (INIS)

    1977-01-01

    From energy policy to the problem of public acceptance of nuclear power, problems like energy supply, energy strategies, the race of industrial countries for the short energy reserves, the West German energy demand until the year 2.000, energy conservation, and the controversy over increased use of nuclear energy are reviewed. (GL) [de

  1. Rethinking medical humanities.

    Science.gov (United States)

    Chiapperino, Luca; Boniolo, Giovanni

    2014-12-01

    This paper questions different conceptions of Medical Humanities in order to provide a clearer understanding of what they are and why they matter. Building upon former attempts, we defend a conception of Medical Humanities as a humanistic problem-based approach to medicine aiming at influencing its nature and practice. In particular, we discuss three main conceptual issues regarding the overall nature of this discipline: (i) a problem-driven approach to Medical Humanities; (ii) the need for an integration of Medical Humanities into medicine; (iii) the methodological requirements that could render Medical Humanities an effective framework for medical decision-making.

  2. STS-1 medical report

    Science.gov (United States)

    Pool, S. L. (Editor); Johnson, P. C., Jr. (Editor); Mason, J. A. (Editor)

    1981-01-01

    The report includes a review of the health of the crew before, during and immediately after the first Shuttle orbital flight (April 12-14, 1981). Areas reviewed include: health evaluation, medical debriefing of crewmembers, health stabilization program, medical training, medical kit carried inflight; tests and countermeasures for space motion sickness, cardiovascular profile, biochemistry and endocrinology results; hematology and immunology analyses; medical microbiology; food and nutrition; potable water; shuttle toxicology; radiological health; cabin acoustical noise. Also included is information on: environmental effects of Shuttle launch and landing, medical information management; and management, planning and implementation of the medical program.

  3. Tidal energy

    International Nuclear Information System (INIS)

    Lochte, H.G.

    1995-01-01

    Together with wave energy, ocean thermal energy, and the often overlooked energy from ocean curents tidal energy belongs to those renewable energy sources that can be subsumed under the generic term of ocean energy. All that these energy sources have in common, however, is that they are found in the ocean. The present article discusses tidal energy with respect to the four principal factors determining the scope of a renewable energy source, namely global, technical, and economic availability and ecological acceptability. (orig.) [de

  4. Radiation protection in medical applications

    International Nuclear Information System (INIS)

    Maldonado M, H.

    2008-12-01

    The justification of the practices is the fundamental principle on which rests the peaceful use of ionizing radiations. They actually contain as aspirations to improve the quality of people's lives, contributing to sustainable development through environmental protection, so that the sources security and the individuals protection will be conditions which are not and should can not be operated. For medical applications is a highly illustrative example of this, since both for the diagnosis and therapy, the goal is to achieve what is sought for the white tissue, secured the least possible damage to the neighboring tissues so that in turn reduce the negative effects for the patient. As a basis for achieving the above, it is essential to have qualified personnel in all areas incidents, for example users, workers, officials and staff members. There are a variety of specialists in the field of medical applications as, nuclear chemistry, nuclear engineering, radiation protection, medical physics, radiation physics and others. Among the human resource in the country must make up the majority are medical radiologists, highlighting gaps in the number of radiotherapy and nuclear medicine but specially in the medical physics, who is in some way from a special viewpoint of the formal school, new to the country. This is true for the number of facilities which are in the country. The radiation protection responsibilities in medical applications focus primarily on two figures: the radiology safety manager, who is primarily dedicated to the protection of occupationally exposed personnel and the public, and the medical physicist whose functions are geared towards the radiological protection of the patient. The principal legislation in the medical applications area has been enacted and is monitored by the Health Secretary and National Commission on Nuclear Safety and Safeguards, entities that have reached agreements to avoid overlap and over-regulation. Medical applications in the

  5. Radiosterilization of medical products, pharmaceuticals and bioproducts

    International Nuclear Information System (INIS)

    1967-01-01

    A Panel on the Radiosterilization of Medical Products, Pharmaceuticals and Bioproducts was convened by the International Atomic Energy Agency on 17-19 January 1966 at its headquarters in Vienna. The purpose of the meeting was to survey the activities of the Member States in this field with a view to preparing the way for an international code of practice for the radiosterilization of medical products, in conformity with existing legal international rules. Refs, figs and tabs

  6. Energy Fact Sheets - Sandia Energy

    Science.gov (United States)

    Energy Energy Secure & Sustainable Energy Future Search Icon Sandia Home Locations Contact Us Employee Locator Menu Stationary Power solar Energy Conversion Efficiency Increasing the amount of electricity produced from a given thermal energy input. Solar Energy Wind Energy Water Power Supercritical CO2

  7. Polymyositis: Medical Management

    Science.gov (United States)

    ... Donate Search MDA.org Close Polymyositis (PM) Medical Management Polymyositis (PM) is a highly treatable disease. Some ... PM) Signs and Symptoms Diagnosis Causes/Inheritance Medical Management Research Find your MDA Care Center Grants at ...

  8. Medications (for IBS)

    Medline Plus

    Full Text Available ... Treating IBS Pain IBS Global Treatments IBS Diet Low FODMAP Diet Complementary or Alternative Treatments Medications Psychological ... Treating IBS Pain IBS Global Treatments IBS Diet Low FODMAP Diet Complementary or Alternative Treatments Medications Psychological ...

  9. South African Medical Journal

    African Journals Online (AJOL)

    The South African Medical Journal is published by the South African Medical Association, which represents ... G Watermeyer, S Thomson, 399-402 ... Assessing the value of Western Cape Provincial Government health administrative data and ...

  10. Medications (for IBS)

    Medline Plus

    Full Text Available ... J. Lembo, MD, Instructor of Medicine, Harvard Medical School; Division of Gastroenterology, Beth Israel Deaconess Medical Center, ... About IFFGD Our Mission Awareness Activities Advocacy Activities Research Leadership Industry Council Contact us IBS Treatment Working ...

  11. Medications (for IBS)

    Medline Plus

    Full Text Available ... by a physician who specializes in motility or stress-related gastrointestinal disorders. More complex medication regimens, and ... IBS Medications Probiotics and Antibiotics Psychological Treatments Understanding Stress Cognitive Behavioral Therapy Relaxation Techniques for IBS Take ...

  12. Medications (for IBS)

    Medline Plus

    Full Text Available ... effective medications available that relieve the pain and improve the changes in bowel habit. They may need ... effective in treating IBS in multi-center, high quality clinical trials. These are prescription medications intended for ...

  13. Medications (for IBS)

    Medline Plus

    Full Text Available ... Gallery Contact Us About IBS Twitter Facebook YouTube Search Search ... About Us What is IBS? What is IBS? ... the Day Art of IBS Gallery Contact Us Search Medications Details Medications Last Updated: 01 July 2017 ...

  14. Medications (for IBS)

    Medline Plus

    Full Text Available ... Diet Complementary or Alternative Treatments Medications Psychological Treatments Online Studies News You Can Use Living With IBS ... Diet Complementary or Alternative Treatments Medications Psychological Treatments Online Studies News You Can Use Living With IBS ...

  15. Medications (for IBS)

    Medline Plus

    Full Text Available ... He or she can help you monitor quality, effectiveness, possible interactions with other medicines you may be ... Read more about newer IBS medications. Summary The effectiveness of various agents differs between individuals. A medication ...

  16. Understanding Medical Research

    Science.gov (United States)

    ... you hear about the results of a new medical research study. Sometimes the results of one study ... when reading or listening to reports of new medical findings. Some questions that can help you evaluate ...

  17. Medical Device Safety

    Science.gov (United States)

    A medical device is any product used to diagnose, cure, or treat a condition, or to prevent disease. They ... may need one in a hospital. To use medical devices safely Know how your device works. Keep ...

  18. Emergency Medical Services

    Science.gov (United States)

    ... need help right away, you should use emergency medical services. These services use specially trained people and ... emergencies, you need help where you are. Emergency medical technicians, or EMTs, do specific rescue jobs. They ...

  19. Medications (for IBS)

    Medline Plus

    Full Text Available ... for some people with IBS, mainly those with emotional distress. There are also effective medications available that ... not linked to depression, but rather likely to effects on the brain and the gut. Antidepressant medications ...

  20. Federal Medication Terminologies

    Science.gov (United States)

    Federal Medication (FedMed) collaboration of 8 partner agencies agreed on a set of standard, comprehensive, freely and easily accessible FMT terminologies to improve the exchange and public availability of medication information.

  1. Marijuana: modern medical chimaera.

    Science.gov (United States)

    Lamarine, Roland J

    2012-01-01

    Marijuana has been used medically since antiquity. In recent years there has been a resurgence of interest in medical applications of various cannabis preparations. These drugs have been cited in the medical literature as potential secondary treatment agents for severe pain, muscle spasticity, anorexia, nausea, sleep disturbances, and numerous other uses. This article reviews the research literature related to medical applications of various forms of cannabis. Benefits related to medical use of cannabinoids are examined and a number of potential risks associated with cannabis use, both medical and recreational, are considered. There is a clearly identified need for further research to isolate significant benefits from the medical application of cannabinoids and to establish dosage levels, appropriate delivery mechanisms and formulations, and to determine what role, if any, cannabinoids might play in legitimate medical applications. It is also imperative to determine if reported dangers pose a significant health risks to users.

  2. Medications (for IBS)

    Medline Plus

    Full Text Available ... Medications Psychological Treatments Online Studies Living With IBS Relationships and IBS Pregnancy and IBS Travel and IBS ... Medications Psychological Treatments Online Studies Living With IBS Relationships and IBS Pregnancy and IBS Travel and IBS ...

  3. Medications (for IBS)

    Medline Plus

    Full Text Available ... With IBS Relationships and IBS Pregnancy and IBS Travel and IBS IBS Patients' Experience and Unmet Needs IBS and ... Agents Antidiarrheal Agents Antidepressant Medications Newer IBS Medications Probiotics ...

  4. Rationing medical education.

    African Journals Online (AJOL)

    This paper discussed the pros and cons of the application of rationing to medical education and the different ... Even though some stakeholders in medical education might be taken aback at .... Walsh K. Online educational tools to improve the.

  5. Medical Errors Reduction Initiative

    National Research Council Canada - National Science Library

    Mutter, Michael L

    2005-01-01

    The Valley Hospital of Ridgewood, New Jersey, is proposing to extend a limited but highly successful specimen management and medication administration medical errors reduction initiative on a hospital-wide basis...

  6. Medications (for IBS)

    Medline Plus

    Full Text Available ... J. Lembo, MD, Instructor of Medicine, Harvard Medical School; Division of Gastroenterology, Beth Israel Deaconess Medical Center, ... doctor. We advise seeing a physician whenever a health problem arises requiring an expert’s care. © Copyright 1998- ...

  7. Medications (for IBS)

    Medline Plus

    Full Text Available ... Read more about antidiarrheal agents. Anti-anxiety medications – can be helpful for some people with IBS, mainly those with emotional distress. There are also effective medications available that relieve ...

  8. EAST AFRICAN MEDICAL JOURNAL

    African Journals Online (AJOL)

    2003-11-11

    Nov 11, 2003 ... East African Medical Journal Vol. ... Lecturer/Consultant Surgeon, Paediatric Surgery Unit, Department of Surgery, College of Medical Sciences, University of Calabar, .... mind and the results obtained were however satisfying.

  9. Medications (for IBS)

    Medline Plus

    Full Text Available ... Treatments Medications Psychological Treatments Online Studies News You Can Use Living With IBS Relationships and IBS Pregnancy ... Treatments Medications Psychological Treatments Online Studies News You Can Use Living With IBS Relationships and IBS Pregnancy ...

  10. Tanzania Medical Journal

    African Journals Online (AJOL)

    The journal publishes any contribution that advances medical science or ... these core objectives the journal publishes papers on original scientific research, short ... The Tanzania Medical Journal is an international Journal - ISSN: 0856-0719 ...

  11. Medications (for IBS)

    Medline Plus

    Full Text Available ... IBS Global Treatments IBS Diet Low FODMAP Diet Complementary or Alternative Treatments Medications Psychological Treatments Online Studies ... IBS Global Treatments IBS Diet Low FODMAP Diet Complementary or Alternative Treatments Medications Psychological Treatments Online Studies ...

  12. Medications (for IBS)

    Medline Plus

    Full Text Available ... depression, but rather likely to effects on the brain and the gut. Antidepressant medications can reduce the intensity of pain signals going from gut to brain. Read more about antidepressant medications. Newer IBS-Targeted ...

  13. Medications (for IBS)

    Medline Plus

    Full Text Available ... Treatments IBS Diet Low FODMAP Diet Complementary or Alternative Treatments Medications Psychological Treatments Online Studies News You ... Treatments IBS Diet Low FODMAP Diet Complementary or Alternative Treatments Medications Psychological Treatments Online Studies News You ...

  14. Avoiding Medical Identity Theft

    Science.gov (United States)

    ... medical records that can plague your medical and financial life for years, or even put your health at risk. ... Monitor your health records closely and address any errors quickly Share personal and health insurance information only ...

  15. Medical Issues: Orthopedics

    Science.gov (United States)

    ... Information Packets Equipment Pool Living With SMA Medical Issues Palliative Breathing Orthopedics Nutrition Equipment Daily Life At ... curesma.org > support & care > living with sma > medical issues > orthopedics Orthopedics In SMA, muscle weakness can cause ...

  16. Medical Issues: Equipment

    Science.gov (United States)

    ... Information Packets Equipment Pool Living With SMA Medical Issues Palliative Breathing Orthopedics Nutrition Equipment Daily Life At ... curesma.org > support & care > living with sma > medical issues > equipment Equipment Individuals with SMA often require a ...

  17. Medical Issues: Breathing

    Science.gov (United States)

    ... Information Packets Equipment Pool Living With SMA Medical Issues Palliative Breathing Orthopedics Nutrition Equipment Daily Life At ... curesma.org > support & care > living with sma > medical issues > breathing Breathing Breathing problems are the most common ...

  18. Medications (for IBS)

    Medline Plus

    Full Text Available ... of constipation. Laxatives should be used under the supervision of a physician. Read more about laxatives. Bulking ... medications intended for specific use under a doctor’s supervision. Read more about newer IBS medications. Summary The ...

  19. Mental Health Medications

    Science.gov (United States)

    ... for Mental Illnesses Clinical Trials Outreach Outreach Home Stakeholder Engagement Outreach Partnership Program Alliance for Research Progress ... public health by ensuring the safety, efficacy and security of drugs (medications), biological products, medical devices, our ...

  20. Medical Care during Pregnancy

    Science.gov (United States)

    ... for Educators Search English Español Medical Care During Pregnancy KidsHealth / For Parents / Medical Care During Pregnancy What's ... and their babies. What Is Prenatal Care Before Pregnancy? Prenatal care should start before you get pregnant. ...

  1. Applications of Particle Accelerators in Medical Physics

    CERN Document Server

    Cuttone, G

    2008-01-01

    Particle accelerators are often associated to high energy or nuclear physics. As well pointed out in literature [1] if we kindly analyse the number of installation worldwide we can easily note that about 50% is mainly devoted to medical applications (radiotherapy, medical radioisotopes production, biomedical research). Particle accelerators are also playing an important indirect role considering the improvement of the technical features of medical diagnostic. In fact the use of radionuclide for advanced medical imaging is strongly increasing either in conventional radiography (CT and MRI) and also in nuclear medicine for Spect an PET imaging. In this paper role of particle accelerators for medical applications will be presented together with the main solutions applied.

  2. Medical handling of accidentally exposed individuals

    International Nuclear Information System (INIS)

    1988-01-01

    In 1978 the International Atomic Energy Agency issued a publication in the IAEA Safety Series entitled Manual on Early Medical Treatment of Possible Radiation Injury (Safety Series No. 47). The contents were directed to first aid and early medical treatment of workers who might be concerned in an accident involving exposure to radiation, whether external or internal. The present manual is the first of a set of three safety series publications dealing with assessment and treatment of overexposures which will constitute an articulated system of documents covering all aspects of diagnosis, prognosis and treatment of overexposures. This document establishes a set of general criteria and recommendations to aid specialists involved in the medical handling of overexposed persons. It deals with the medical management of individual patients or small groups of patients under close medical supervision. 14 refs, 7 figs, 7 tabs

  3. Implantable electronic medical devices

    CERN Document Server

    Fitzpatrick, Dennis

    2014-01-01

    Implantable Electronic Medical Devices provides a thorough review of the application of implantable devices, illustrating the techniques currently being used together with overviews of the latest commercially available medical devices. This book provides an overview of the design of medical devices and is a reference on existing medical devices. The book groups devices with similar functionality into distinct chapters, looking at the latest design ideas and techniques in each area, including retinal implants, glucose biosensors, cochlear implants, pacemakers, electrical stimulation t

  4. Medical Proton Accelerator Project

    International Nuclear Information System (INIS)

    Comsan, M.N.H.

    2008-01-01

    A project for a medical proton accelerator for cancer treatment is outlined. The project is motivated by the need for a precise modality for cancer curing especially in children. Proton therapy is known by its superior radiation and biological effectiveness as compared to photon or electron therapy. With 26 proton and 3 heavy-ion therapy complexes operating worldwide only one (p) exists in South Africa, and none in south Asia and the Middle East. The accelerator of choice should provide protons with energy 75 MeV for eye treatment and 250 MeV for body treatment. Four treatment rooms are suggested: two with isocentric gantries, one with fixed beams and one for development. Passive scanning is recommended. The project can serve Middle East and North Africa with ∼ 400 million populations. The annual capacity of the project is estimated as 1,100 to be compared with expected radiation cases eligible for proton cancer treatment of not less than 200,000

  5. Medical Schools for Profit?

    African Journals Online (AJOL)

    [3] The same could be said of E-learning in medical education.[4,5] Thirdly allowing profits within medical education should attract more investment. Investors could sink funds into medical education, and learners would benefit as a result; inevitably investors would like to see a return on investment – however, successful.

  6. MANAGEMENT OF MEDICAL SERVICES

    Directory of Open Access Journals (Sweden)

    BARBU MARIA-MAGDALENA

    2009-05-01

    Full Text Available The offer of medical services depends on medical personnel and more than this, on the management in the medical field since any resource not managed well or not managed at all is only a lost one, regardless its value. Management is therefore the key, the

  7. Ghana Medical Journal

    African Journals Online (AJOL)

    The Ghana Medical Journal is a peer-reviewed, open access journal published by the Ghana Medical Association. It was established in 1962 It publishes quality manuscripts in in all aspects of health, health care and the medical sciences. The full text of published articles are available online at this website and at African ...

  8. Sahel Medical Journal

    African Journals Online (AJOL)

    Sahel Medical Journal is a quarterly international Journal devoted solely to (1) dissemination of information about medical sciences in Nigeria, particularly the Sahel zone, Africa and the rest of the world, (2) to provide a medium where national and international medical and health organizations may relay information to ...

  9. Medics in Primary School

    Science.gov (United States)

    Press, Colin

    2003-01-01

    Some time ago a flyer on "Medics in Primary School" came the author's way. It described a programme for making placements in primary schools available to medical students. The benefits of the program to medical students and participating schools were highlighted, including opportunities to develop communication skills and demystify…

  10. Medical Computational Thinking

    DEFF Research Database (Denmark)

    Musaeus, Peter; Tatar, Deborah Gail; Rosen, Michael A.

    2017-01-01

    Computational thinking (CT) in medicine means deliberating when to pursue computer-mediated solutions to medical problems and evaluating when such solutions are worth pursuing in order to assist in medical decision making. Teaching computational thinking (CT) at medical school should be aligned...

  11. Digital medical imaging

    International Nuclear Information System (INIS)

    Goeringer, F.; Mun, S.K.; Kerlin, B.D.

    1989-01-01

    In formulating an implementation strategy for digital medical imaging, three interrelated thrusts have emerged for the defense medical establishment. These thrusts: totally filmless medical imaging on the battlefield, teleradiology, and DIN/PACS for peacetime military health care are discussed. They have implications in their fully developed form as resource savers and quality improvers for the unique aspects of military health care

  12. Marijuana: Modern Medical Chimaera

    Science.gov (United States)

    Lamarine, Roland J.

    2012-01-01

    Marijuana has been used medically since antiquity. In recent years there has been a resurgence of interest in medical applications of various cannabis preparations. These drugs have been cited in the medical literature as potential secondary treatment agents for severe pain, muscle spasticity, anorexia, nausea, sleep disturbances, and numerous…

  13. Medical device development.

    Science.gov (United States)

    Panescu, Dorin

    2009-01-01

    The development of a successful medical product requires not only engineering design efforts, but also clinical, regulatory, marketing and business expertise. This paper reviews items related to the process of designing medical devices. It discusses the steps required to take a medical product idea from concept, through development, verification and validation, regulatory approvals and market release.

  14. Highland Medical Research Journal

    African Journals Online (AJOL)

    The aim of the Highland Medical Research Journal is to publish scientific research in various fields of medical science and to communicate such research findings to the larger world community. It aims to promote cooperation and understanding amoungst workers in various fields of medical science.

  15. Energy options?; Energie opties?

    Energy Technology Data Exchange (ETDEWEB)

    Van Sark, W. (ed.)

    2006-05-15

    March 2006 the so-called Options Document was published by the Energy research Centre of the Netherlands (ECN) and the Netherlands Environmental Assessment Agency (MNP). The document is an overview of technical options to reduce energy consumption and emission of greenhouse gases up to 2020. Next to a brief summary of the document a few reactions and comments on the contents of the document are given. [Dutch] Maart 2006 publiceerde het Energieonderzoek Centrum Nederland (ECN) en het Milieu- en Natuurplanbureau (MNP) het zogenaamde Optiedocument energie en emissies 2010-2020. Daarin wordt een overzicht gegeven van de technische mogelijkheden voor vermindering van het energieverbruik en de uitstoot van broeikasgassen en luchtverontreinigende stoffen tot 2020. Naast een korte samenvatting van het document worden enkele reacties gegeven op de inhoud.

  16. Medical marijuana: Medical necessity versus political agenda

    OpenAIRE

    Clark, Peter A.; Capuzzi, Kevin; Fick, Cameron

    2011-01-01

    Summary Marijuana is classified by the Drug Enforcement Agency (DEA) as an illegal Schedule I drug which has no accepted medical use. However, recent studies have shown that medical marijuana is effective in controlling chronic non-cancer pain, alleviating nausea and vomiting associated with chemotherapy, treating wasting syndrome associated with AIDS, and controlling muscle spasms due to multiple sclerosis. These studies state that the alleviating benefits of marijuana outweigh the negative ...

  17. Estimation of the contribution by neutrons to the equivalent dose for exposed occupationally personnel and people in medical use facilities: X rays of equal or superior energy to 10 MV; Estimacion de la contribucion por neutrones a la dosis equivalente para personal ocupacionalmente expuesto y publico en instalaciones de uso medico: rayos X de energia igual y/o superior a 10 MV

    Energy Technology Data Exchange (ETDEWEB)

    Ortega J, R.; Reyes S, M. A. [Comision Nacional de Seguridad Nuclear y Salvaguardias, Dr. Jose Ma. Barragan 779, Col. Narvarte, 03020 Mexico D. F. (Mexico); Moranchel y R, M., E-mail: rojimenez@cnsns.gob.mx [IPN, Escuela Superior de Fisica y Matematicas, Departamento de Ingenieria Nuclear, Av. Instituto Politecnico Nacional s/n, U. P. Adolfo Lopez Mateos, Edif. 9, Col. San Pedro Zacatenco, 07738 Mexico D. F. (Mexico)

    2013-10-15

    In Mexico the use of electron accelerators for treating cancerous tumors had grown enormously in the last decade. When the treatments are carried out with X-ray beam energy below 10 MV the design of the shielding of the radioactive facility is determined by analyzing the interaction of X-rays, which have a direct impact and dispersion, with materials of the facility. However, when it makes use of X-ray beam energy equal to or greater than 10 MV the neutrons presence is imminent due to their generation by the interaction of the primary beam X-ray with materials head of the accelerator and of the table of treatment, mainly. In these cases, the design and calculation of shielding considers the generation of high-energy neutrons which contribute the equivalent dose that public and occupationally staff exposed (POE) will receive in the areas surrounding the facility radioactive. However, very few measurements have been performed to determine the actual contribution to the neutron dose equivalent received by POE and public during working hours. This paper presents and estimate of the actual contribution of the neutron dose equivalent received by public and POE facilities in various radioactive medical use, considering many factors. To this end, measurements were made of the equivalent dose by using a neutron monitor in areas surrounding different radioactive installations (of Mexico) which used electron accelerators medical use during treatment with X-ray beam energy equal to or greater than 10 MV. The results are presented after a statistical analysis of a wide range of measures in order to estimate more reliability real contribution of the neutron dose equivalent for POE and the public. (author)

  18. Estimation of the contribution of neutrons to the equivalent dose for personnel occupationally exposed and public in medical facilities: X-ray with energy equal or greater than 10MV; Estimacion de la contribucion por neutrones a la dosis equivalente para personal ocupacionalmente expuesto y publico en instalaciones de uso medico: rayos X de energia igual y/o superior a 10MV

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez, Alfonso Mayer; Jimenez, Roberto Ortega; Sanchez, Mario A. Reyes, E-mail: amgesfm@hotmail.com, E-mail: rojimenez@cnsns.gob.mx [Comision Nacional de Seguridad Nuclear y Salvaguardias (CNSNS), Mexico, D.F. (Mexico); Moranchel y Mejia, Mario, E-mail: mmoranchel@ipn.mx [Instituto Politecnico Nacional (ESFM/IPN), Mexico, D.F. (Mexico). Escuela Superior de Fisica y Matematicas. Departamento de lngenieria Nuclear

    2013-07-01

    In Mexico the use of electron accelerators for treating cancerous tumors had grown enormously in the last decade. When the treatments are carried out with X-ray beam energy below 10 MV the design of the shielding of the radioactive facility is determined by analyzing the interaction of X-rays, which have a direct impact and dispersion, with materials of the facility. However, when it makes use of X-ray beam energy equal to or greater than 10 MV the neutrons presence is imminent due to their generation by the interaction of the primary beam X-ray with materials head of the accelerator and of the table of treatment, mainly. In these cases, the design and calculation of shielding considers the generation of high-energy neutrons which contribute the equivalent dose that public and Occupationally Staff Exposed (POE) will receive in the areas surrounding the facility radioactive. However, very few measurements have been performed to determine the actual contribution to the neutron dose equivalent received by POE and public during working hours. This paper presents an estimate of the actual contribution of the neutron dose equivalent received by public and POE facilities in various radioactive medical use, considering many factors. To this end, measurements were made of the equivalent dose by using a neutron monitor in areas surrounding different radioactive installations (of Mexico) which used electron accelerators medical use during treatment with X-ray beam energy equal to or greater than 10 MV. The results are presented after a statistical analysis of a wide range of measures in order to estimate more reliability real contribution of the neutron dose equivalent for POE and the public. (author)

  19. Energy Technology.

    Science.gov (United States)

    Eaton, William W.

    Reviewed are technological problems faced in energy production including locating, recovering, developing, storing, and distributing energy in clean, convenient, economical, and environmentally satisfactory manners. The energy resources of coal, oil, natural gas, hydroelectric power, nuclear energy, solar energy, geothermal energy, winds, tides,…

  20. MEDIC: medical embedded device for individualized care.

    Science.gov (United States)

    Wu, Winston H; Bui, Alex A T; Batalin, Maxim A; Au, Lawrence K; Binney, Jonathan D; Kaiser, William J

    2008-02-01

    Presented work highlights the development and initial validation of a medical embedded device for individualized care (MEDIC), which is based on a novel software architecture, enabling sensor management and disease prediction capabilities, and commercially available microelectronic components, sensors and conventional personal digital assistant (PDA) (or a cell phone). In this paper, we present a general architecture for a wearable sensor system that can be customized to an individual patient's needs. This architecture is based on embedded artificial intelligence that permits autonomous operation, sensor management and inference, and may be applied to a general purpose wearable medical diagnostics. A prototype of the system has been developed based on a standard PDA and wireless sensor nodes equipped with commercially available Bluetooth radio components, permitting real-time streaming of high-bandwidth data from various physiological and contextual sensors. We also present the results of abnormal gait diagnosis using the complete system from our evaluation, and illustrate how the wearable system and its operation can be remotely configured and managed by either enterprise systems or medical personnel at centralized locations. By using commercially available hardware components and software architecture presented in this paper, the MEDIC system can be rapidly configured, providing medical researchers with broadband sensor data from remote patients and platform access to best adapt operation for diagnostic operation objectives.

  1. The Muddle of Medicalization

    DEFF Research Database (Denmark)

    Sholl, Jonathan

    2017-01-01

    to describe inappropriate or abusive instances of medical authority. Yet, while this standard approach claims that medicalization is a growing problem, it assumes that there is simply one “medical model” and that the expanding realm of “the medical” can be more or less clearly delineated. Moreover, while...... of medical discourse. In doing so, I will explore the distinction between medicalization and pathologization, a distinction that is often overlooked and that brings with it many conceptual and practical implications. After defining these terms, I will use some examples to show that while pathologizing...

  2. Advanced Medication Dispenser

    Directory of Open Access Journals (Sweden)

    A.I. Alexan

    2013-12-01

    Full Text Available Medication dispensing is an important activity that can have major implications if done improperly. Dispensing must be done in the correct time interval, at the correct user, with the correct drug and dose. We propose a smart medication dispenser that can satisfy these needs and provide a mechanism for supervision. In order to ensure that the dispensing process is error free, the concept of a new smart medication container is used. A smart medication container is “smart” as it holds the medication dispensing parameters for the drugs it contains: dispensing time and date and name. Based on this information, the actual dispensing is done.

  3. [Research in medical education

    DEFF Research Database (Denmark)

    Ringsted, Charlotte Vibeke

    2008-01-01

    Research in medical education is a relatively new discipline. Over the past 30 years, the discipline has experienced a tremendous growth, which is reflected in an increase in the number of publications in both medical education journals and medical science journals. However, recent reviews...... of articles on medical education studies indicate a need for improvement of the quality of medical education research in order to contribute to the advancement of educational practice as well as educational research. In particular, there is a need to embed studies in a conceptual theoretical framework...

  4. Technologies for Medical Sciences

    CERN Document Server

    Tavares, João; Barbosa, Marcos; Slade, AP

    2012-01-01

    This book presents novel and advanced technologies for medical sciences in order to solidify knowledge in the related fields and define their key stakeholders.   The fifteen papers included in this book were written by invited experts of international stature and address important technologies for medical sciences, including: computational modeling and simulation, image processing and analysis, medical imaging, human motion and posture, tissue engineering, design and development medical devices, and mechanic biology. Different applications are treated in such diverse fields as biomechanical studies, prosthesis and orthosis, medical diagnosis, sport, and virtual reality.   This book is of interest to researchers, students and manufacturers from  a wide range of disciplines related to bioengineering, biomechanics, computational mechanics, computational vision, human motion, mathematics, medical devices, medical image, medicine and physics.

  5. [Unravelling medical leadership].

    Science.gov (United States)

    Voogt, Judith J; van Rensen, Elizabeth L J; Noordegraaf, Mirko; Schneider, Margriet M E

    2015-01-01

    Medical leadership is a popular topic in the Netherlands, and several interest groups now incorporate medical leadership into postgraduate medical education. However, there is no consensus on what this concept entails. By conducting a discourse analysis, a qualitative method which uses language and text to reveal existing viewpoints, this article reveals three perspectives on medical leadership: administrative leadership, leadership within organisations and leadership within each doctor's daily practice. Text analysis shows that the first two perspectives refer to medical leadership mainly in a defensive manner: by demonstrating medical leadership doctors could 'take the lead' once again; patient care only seems to play a small part in the process. These perspectives are not free of consequences, they will determine how the medical profession is constructed. For this reason, it is argued that there should be more emphasis on the third perspective, in which the quality of care for patients is of primary importance.

  6. Energy storage

    International Nuclear Information System (INIS)

    2012-01-01

    After having outlined the importance of energy storage in the present context, this document outlines that it is an answer to economic, environmental and technological issues. It proposes a brief overview of the various techniques of energy storage: under the form of chemical energy (hydrocarbons, biomass, hydrogen production), thermal energy (sensitive or latent heat storage), mechanical energy (potential energy by hydraulic or compressed air storage, kinetic energy with flywheels), electrochemical energy (in batteries), electric energy (super-capacitors, superconductor magnetic energy storage). Perspectives are briefly evoked

  7. CERN crystals used in medical imaging

    CERN Multimedia

    Maximilien Brice

    2004-01-01

    This crystal is a type of material known as a scintillator. When a high energy charged particle or photon passes through a scintillator it glows. These materials are widely used in particle physics for particle detection, but their uses are being realized in further fields, such as Positron Emission Tomography (PET), an area of medical imaging that monitors the regions of energy use in the body.

  8. Renewable energy

    International Nuclear Information System (INIS)

    Yoon, Cheon Seok

    2009-09-01

    This book tells of renewable energy giving description of environment problem, market of renewable energy and vision and economics of renewable energy. It also deals with solar light like solar cell, materials performance, system and merit of solar cell, solar thermal power such as solar cooker and solar collector, wind energy, geothermal energy, ocean energy like tidal power and ocean thermal energy conversion, fuel cell and biomass.

  9. Energy storage

    International Nuclear Information System (INIS)

    Anon.

    1992-01-01

    This chapter discusses the role that energy storage may have on the energy future of the US. The topics discussed in the chapter include historical aspects of energy storage, thermal energy storage including sensible heat storage, latent heat storage, thermochemical heat storage, and seasonal heat storage, electricity storage including batteries, pumped hydroelectric storage, compressed air energy storage, and superconducting magnetic energy storage, and production and combustion of hydrogen as an energy storage option

  10. Dossier Energy

    International Nuclear Information System (INIS)

    Weijer, H.; Holwerda, B.; Schrauwers, A.; Van de Graaf, A.; Van Gelder, T.

    2003-01-01

    Several aspects with respect to energy are discussed in a special section of this magazine: the security of energy supply in a liberalized market, saving energy by outsourcing (e.g. compressed air contracting), the profits of a liberalized energy market for businesses, incentives for energy saving projects and innovations, an energy efficiency project at Ineos Silicas (producer of zeolites), and energy efficient electronic equipment [nl

  11. Energy intermittency

    CERN Document Server

    Sorensen, Bent

    2014-01-01

    The first book to consider intermittency as a key point of an energy system, Energy Intermittency describes different levels of variability for traditional and renewable energy sources, presenting detailed solutions for handling energy intermittency through trade, collaboration, demand management, and active energy storage. Addressing energy supply intermittency systematically, this practical text:Analyzes typical time-distributions and intervals between episodes of demand-supply mismatch and explores their dependence on system layouts and energy source characteristicsSimulates scenarios regar

  12. Energy sustainability through green energy

    CERN Document Server

    Sharma, Atul

    2015-01-01

    This book shares the latest developments and advances in materials and processes involved in the energy generation, transmission, distribution and storage. Chapters are written by researchers in the energy and materials field. Topics include, but are not limited to, energy from biomass, bio-gas and bio-fuels; solar, wind, geothermal, hydro power, wave energy; energy-transmission, distribution and storage; energy-efficient lighting buildings; energy sustainability; hydrogen and fuel cells; energy policy for new and renewable energy technologies and education for sustainable energy development

  13. Renewable energy.

    Science.gov (United States)

    Destouni, Georgia; Frank, Harry

    2010-01-01

    The Energy Committee of the Royal Swedish Academy of Sciences has in a series of projects gathered information and knowledge on renewable energy from various sources, both within and outside the academic world. In this article, we synthesize and summarize some of the main points on renewable energy from the various Energy Committee projects and the Committee's Energy 2050 symposium, regarding energy from water and wind, bioenergy, and solar energy. We further summarize the Energy Committee's scenario estimates of future renewable energy contributions to the global energy system, and other presentations given at the Energy 2050 symposium. In general, international coordination and investment in energy research and development is crucial to enable future reliance on renewable energy sources with minimal fossil fuel use.

  14. Energy assessments

    International Nuclear Information System (INIS)

    Unruh, T.D.

    1998-01-01

    Energy industry initiatives during the 1970s and during the 1990s are compared. During the 1970s, the objective was to reduce energy consumption and to reduce dependency on foreign fuel. Today, the emphasis is on reducing energy costs and to improve net operating income. The challenges posed by the drive to reduce energy costs are discussed. As a tool in the drive to reduce energy cost, the energy assessment process was described. The process entails a detailed analysis of energy consumption, an investigation of energy rates and an assessment of site conditions and equipment, with a view towards an optimum combination that will lead to energy cost reductions

  15. Energy needs

    International Nuclear Information System (INIS)

    Chateau, Bertrand

    2014-05-01

    The author first discusses the various concepts and definitions associated with energy needs, and then the difference between actual needs and energy needs by distinguishing personal needs, needs of the productive sector, energetic needs and services. In the next part, he discusses how energy needs are assessed. He discusses the relationship between energy needs and energy consumption, how energy consumptions can be analysed and interpreted. He comments how energy needs can be assessed and analysed in time and in space. He notices and explains why economy and climate are the main causes of spatial differences for energy needs per habitant, and comments the evolution of energy consumption over long periods

  16. Energy resources

    CERN Document Server

    Simon, Andrew L

    1975-01-01

    Energy Resources mainly focuses on energy, including its definition, historical perspective, sources, utilization, and conservation. This text first explains what energy is and what its uses are. This book then explains coal, oil, and natural gas, which are some of the common energy sources used by various industries. Other energy sources such as wind, solar, geothermal, water, and nuclear energy sources are also tackled. This text also looks into fusion energy and techniques of energy conversion. This book concludes by explaining the energy allocation and utilization crisis. This publ

  17. Solar Energy.

    Science.gov (United States)

    Eaton, William W.

    Presented is the utilization of solar radiation as an energy resource principally for the production of electricity. Included are discussions of solar thermal conversion, photovoltic conversion, wind energy, and energy from ocean temperature differences. Future solar energy plans, the role of solar energy in plant and fossil fuel production, and…

  18. Understanding Energy

    Science.gov (United States)

    Menon, Deepika; Shelby, Blake; Mattingly, Christine

    2016-01-01

    "Energy" is a term often used in everyday language. Even young children associate energy with the food they eat, feeling tired after playing soccer, or when asked to turn the lights off to save light energy. However, they may not have the scientific conceptual understanding of energy at this age. Teaching energy and matter could be…

  19. Wind energy

    International Nuclear Information System (INIS)

    Anon.

    1992-01-01

    This chapter discusses the role wind energy may have in the energy future of the US. The topics discussed in the chapter include historical aspects of wind energy use, the wind energy resource, wind energy technology including intermediate-size and small wind turbines and intermittency of wind power, public attitudes toward wind power, and environmental, siting and land use issues

  20. Energy policy

    International Nuclear Information System (INIS)

    Forrester, J.W.

    1979-01-01

    The author places the energy problem in the context of world economy. The various obstacles encountered in the United States to spell out a viable national energy policy are cited. A certain number of practical proposals is given to lead to an 'effective policy' which would allow energy economy at the same time as energy development, that is, including nuclear energy [fr

  1. Methodology for carrying out energy diagnosis in auxiliaries systems in thermal electrical central stations; Metodologia para realizar un diagnostico energetico en sistemas auxiliares de centrales termoelectricas

    Energy Technology Data Exchange (ETDEWEB)

    Nebradt Garcia, Jesus [Comision Federal de Electricidad (CFE), Mexico, D. F. (Mexico); Rojas Hidalgo, Ismael; Huante Perez, Liborio [Instituto de Investigaciones Electricas, Cuernavaca (Mexico)

    1998-12-31

    One of the potential areas for energy saving in Central Electric Power Plants are the auxiliaries system, so as to based in a preliminary energy diagnosis and considering that energy saving measures would be taken, going from the instrumentation, operational changes in equipment, as well as in using velocity variators in motors, it turns out to be that the energy consumption of auxiliaries at 75% load in a 150 MW thermal power plant varies from 3% to 4% and for the case of a 350 MW power plant the energy consumption of the auxiliaries represents 2 to 3.5%. Nowadays this consumption are above 6%. Considering that the country has 40 units with capacities varying from 150 to 350 MW, the economical and the fuel saving would be substantial. This paper will present a summary of the methodology to be used to carry out this type of projects. [Espanol] Una de las areas potenciales de ahorro de energia en centrales termoelectricas son los sistemas auxiliares, de tal manera que basados en un diagnostico energetico preliminar y considerando que se aplicarian las medidas de ahorro de energia que van desde la instrumentacion, cambios operativos en equipos, asi como el uso de variadores de velocidad en motores, se tienen que los consumos de auxiliares para un 75% de carga en una central termoelectrica de 150 MW varian desde un 3% hasta un 4% y para el caso de una central termoelectrica de 350 MW, el consumo de auxiliares representa del 2 al 3.5%. Hoy en dia dichos consumos estan por encima del 6%. Si consideramos que el pais cuenta con 40 unidades que varian desde 150 MW hasta 350 MW, entonces los ahorros economicos y de combustible serian impactantes. La presente ponencia mostrara un resumen de la metodologia a emplear para la realizacion de este tipo de proyectos.

  2. Methodology for carrying out energy diagnosis in auxiliaries systems in thermal electrical central stations; Metodologia para realizar un diagnostico energetico en sistemas auxiliares de centrales termoelectricas

    Energy Technology Data Exchange (ETDEWEB)

    Nebradt Garcia, Jesus [Comision Federal de Electricidad (CFE), Mexico, D. F. (Mexico); Rojas Hidalgo, Ismael; Huante Perez, Liborio [Instituto de Investigaciones Electricas, Cuernavaca (Mexico)

    1999-12-31

    One of the potential areas for energy saving in Central Electric Power Plants are the auxiliaries system, so as to based in a preliminary energy diagnosis and considering that energy saving measures would be taken, going from the instrumentation, operational changes in equipment, as well as in using velocity variators in motors, it turns out to be that the energy consumption of auxiliaries at 75% load in a 150 MW thermal power plant varies from 3% to 4% and for the case of a 350 MW power plant the energy consumption of the auxiliaries represents 2 to 3.5%. Nowadays this consumption are above 6%. Considering that the country has 40 units with capacities varying from 150 to 350 MW, the economical and the fuel saving would be substantial. This paper will present a summary of the methodology to be used to carry out this type of projects. [Espanol] Una de las areas potenciales de ahorro de energia en centrales termoelectricas son los sistemas auxiliares, de tal manera que basados en un diagnostico energetico preliminar y considerando que se aplicarian las medidas de ahorro de energia que van desde la instrumentacion, cambios operativos en equipos, asi como el uso de variadores de velocidad en motores, se tienen que los consumos de auxiliares para un 75% de carga en una central termoelectrica de 150 MW varian desde un 3% hasta un 4% y para el caso de una central termoelectrica de 350 MW, el consumo de auxiliares representa del 2 al 3.5%. Hoy en dia dichos consumos estan por encima del 6%. Si consideramos que el pais cuenta con 40 unidades que varian desde 150 MW hasta 350 MW, entonces los ahorros economicos y de combustible serian impactantes. La presente ponencia mostrara un resumen de la metodologia a emplear para la realizacion de este tipo de proyectos.

  3. Production of Medical Isotopes with Electron Linacs

    Energy Technology Data Exchange (ETDEWEB)

    Rotsch, D A; Alford, K.; Bailey, J. L.; Bowers, D. L.; Brossard, T.; Brown, M. A.; Chemerisov, S. D.; Ehst, D.; Greene, J.; Gromov, R. G.; Grudzinski, J.J.; Hafenrichter, L.; Hebden, A. S.; Henning, W.; Heltemes, T. A.; Jerden, J.; Jonah, C. D.; Kalensky, M.; Krebs, J. F.; Makarashvili, V.; Micklich, B.; Nolen, J.; Quigley, K. J.; Schneider, J. F.; Smith, N. A.; Stepinski, D. C.; Sun, Z.; Tkac, P.; Vandegrift, G. F.; Virgo, M J; Wesolowski, K. A.; Youker, A. J.

    2017-06-01

    Radioisotopes play important roles in numerous areas ranging from medical treatments to national security and basic research. Radionuclide production technology for medical applications has been pursued since the early 1900s both commercially and in nuclear science centers. Many medical isotopes are now in routine production and are used in day-to-day medical procedures. Despite these advancements, research is accelerating around the world to improve the existing production methodologies as well as to develop novel radionuclides for new medical appli-cations. Electron linear accelerators (linacs) represent a unique method for the production of radioisotopes. Even though the basic technology has been around for decades, only recently have electron linacs capable of producing photons with sufficient energy and flux for radioisotope production become available. Housed in Argonne Nation-al Laboratory’s Low Energy Accelerator Facility (LEAF) is a newly upgraded 55 MeV/25-kW electron linear ac-celerator, capable of producing a wide range of radioiso-topes. This talk will focus on the work being performed for the production of the medical isotopes 99Mo (99Mo/99mTc generator), 67Cu, and 47Sc.

  4. Breakfast eating habits among medical students.

    Science.gov (United States)

    Ackuaku-Dogbe, E M; Abaidoo, B

    2014-06-01

    Breakfast is often thought to be the most important meal of the day as it is known to provide energy for the brain and improve learning. It is also known to contribute significantly to the total daily energy and nutrient intake. Skipping breakfast may affect performance during the rest of the day. To determine the level of breakfast skipping among medical students and its effect on their attention span and level of fatigue during clinical sessions. A descriptive cross-sectional study of breakfast eating habits among medical students at the University of Ghana Medical School, Korle Bu-Accra. The University of Ghana Medical School, Korle Bu-Accra. Questionnaires were distributed to second year (pre-clinical) medical students studying the basic sciences and clinical students in ophthalmology to be self-administered. Interview data was captured and analyzed using SPSS version 17.0. The total number of pre-clinical students recruited was 154 and clinical students 163 bringing to a total of 317 students made up of 203 males and 114 females (M: F=1.8:1). The overall breakfast skipping among the students was 71.92%. The prevalence among the pre-clinical students was 76.62% and clinical students 67.48%. Generally, breakfast skipping was significantly related to fatigue and poor attention during clinical sessions. This study suggests that the medical students, both pre-clinical and clinical, skip breakfast and this may affect their studies adversely.

  5. Medical design anthropology

    DEFF Research Database (Denmark)

    Ventura, Jonathan; Gunn, Wendy

    Barnard and Spencer define medical anthropology in the Encyclopedia of Social and Cultural Anthropology as "Medical anthropology is, as the phrase implies, unavoidably concerned with the paradigm of modern Western medicine, whether implicitly or explicitly" (2002: 541). Recently there is a new...... focus in medical sociology and anthropology, which is patient's practices and influence on wider global health environment (see for example vol. 36(2) of Sociology of Health & Illness). While various social science theoreticians have written about agentic abilities of objects, there is a gap...... in literature concerning various levels of socio-cultural influence of the medical environment through medical products. In our research we have outlined the importance of medical design anthropology (MDA) to the practice and theory of design (Ventura and Gunn, 2016). In this paper, we study the ways in which...

  6. Book Reviews | Naidu | South African Medical Journal

    African Journals Online (AJOL)

    Book Review 1. Book Title: Medical Radionuclides: Radiation Dose and Effects. Book Authors: R. J. Cloutier, C. L. Edwards & W. S. Snyder (Ed.) Pp. ix + 528. Illustrated. $3.00. Oak Ridge, Tenn.: US Atomic Energy Commission. 1970. Available from Clearinghouse for Federal Scientific and Technical Information, Springfield, ...

  7. Medical Sciences Division report for 1993

    International Nuclear Information System (INIS)

    1993-01-01

    This year's Medical Sciences Division (MSD) Report is organized to show how programs in our division contribute to the core competencies of Oak Ridge Institute for Science and Education (ORISE). ORISE's core competencies in education and training, environmental and safety evaluation and analysis, occupational and environmental health, and enabling research support the overall mission of the US Department of Energy (DOE)

  8. Special radiation protection aspects of medical accelerators

    CERN Document Server

    Silari, Marco

    2001-01-01

    Radiation protection aspects relevant to medical accelerators are discussed. An overview is first given of general safety requirements. Next. shielding and labyrinth design are discussed in some detail for the various types of accelerators, devoting more attention to hadron machines as they are far less conventional than electron linear accelerators. Some specific aspects related to patient protection are also addressed. Finally, induced radioactivity in accelerator components and shielding walls is briefly discussed. Three classes of machines are considered: (1) medical electron linacs for 'conventional' radiation therapy. (2) low energy cyclotrons for production of radionuclides mainly for medical diagnostics and (3) medium energy cyclotrons and synchrotrons for advanced radiation therapy with protons or light ion beams (hadron therapy). (51 refs).

  9. Medical tourism in India.

    Science.gov (United States)

    Gupta, Vijay; Das, Poonam

    2012-06-01

    The term 'medical tourism' is under debate because health care is a serious business and rarely do patients combine the two. India is uniquely placed by virtue of its skilled manpower, common language, diverse medical conditions that doctors deal with, the volume of patients, and a large nonresident Indian population overseas. Medical tourism requires dedicated services to alleviate the anxiety of foreign patients. These include translation, currency conversion, travel, visa, posttreatment care system,and accommodation of patient relatives during and after treatment.

  10. MEDICAL LAW AND ETHICS

    OpenAIRE

    Sunčica Ivanović; Čedomirka Stanojević; Slađana Jajić; Ana Vila; Svetlana Nikolić

    2013-01-01

    The subject of interest in this article is the importance of knowing and connecting medical ethics and medical law for the category of health workers. The author believes that knowledge of bioethics which as a discipline deals with the study of ethical issues and health care law as a legal discipline, as well as medical activity in general, result in the awareness of health professionals of human rights, and since the performance of activities of health workers is almost always linked...

  11. Fundamentals of Medical Ultrasonics

    CERN Document Server

    Postema, Michiel

    2011-01-01

    This book sets out the physical and engineering principles of acoustics and ultrasound as used for medical applications. It covers the basics of linear acoustics, wave propagation, non-linear acoustics, acoustic properties of tissue, transducer components, and ultrasonic imaging modes, as well as the most common diagnostic and therapeutic applications. It offers students and professionals in medical physics and engineering a detailed overview of the technical aspects of medical ultrasonic imaging, whilst serving as a reference for clinical and research staff.

  12. Skylab medical technology utilization

    Science.gov (United States)

    Stonesifer, J. C.

    1974-01-01

    To perform the extensive medical experimentation on man in a long-term, zero-g environment, new medical measuring and monitoring equipment had to be developed, new techniques in training and operations were required, and new methods of collecting and analyzing the great amounts of medical data were developed. Examples of technology transfers to the public sector resulted from the development of new equipment, methods, techniques, and data. This paper describes several of the examples that stemmed directly from Skylab technology.

  13. REMINDER FROM MEDICAL SERVICE

    CERN Multimedia

    Medical Service

    2002-01-01

    For medical problems, we would like to remind all personnel working on the CERN sites, staff members or from outside firms, that they are welcome at the Infirmary, building 57, ground floor. For information, call the nurses: on telephone: 73802 by e-mail: Service.Medical@cern.ch Francoise.Lebrun-Klauser@cern.ch Mireille.Vosdey@cern.ch Katie.Warrillow-Thomson@cern.ch Medical Service

  14. Reminder from Medical Service

    CERN Multimedia

    Medical Service

    2004-01-01

    For medical problems, we would like to remind all personnel working on the CERN sites, staff members or from outside firms, that they are welcome at the Infirmary, building 57, ground floor. For information, call the nurses on telephone: 73802 by e-mail: Service.Medical@cern.ch Francoise.Lebrun-Klauser@cern.ch Mireille.Vosdey@cern.ch Katie.Warrillow-Thomson@cern.ch Medical Service

  15. Computerized medical convocations

    International Nuclear Information System (INIS)

    Roche, Annie; Gilbert, Jean-Francois; Chiadot, Pierre; Vanzetto, Rene; Darnault, Jean

    1969-06-01

    Thanks to a close collaboration between the Medical and Social department and the Numerical Calculation Laboratory, a computerized convocation system has been implemented to reduce the administrative workload and to introduce more rigor in medical management, patient historical background and statistics. This work comprises: - a preliminary study of the data generating medical convocations and the related practical requirements; - the programming work according to these data; - the realisation of the mechano-graphical file covering the overall personnel [fr

  16. Medical Rituals and Media Rituals

    OpenAIRE

    Zoltán Zsinkó-Szabó

    2013-01-01

    In the present article the author examines the ritual elements of theprofessionalization during medical studies, and its interference with media content of medical significance, comparing the role of medical and media rituals on the way of becoming a doctor. It is to be explored how these medical soap operas, medical dramas, medical thrillers or crime stories do exert influence on medical identity and role expectations. Do medical students and their relatives (withmedical expertise frequently...

  17. Cannabinoids: Medical implications.

    Science.gov (United States)

    Schrot, Richard J; Hubbard, John R

    2016-01-01

    Herbal cannabis has been used for thousands of years for medical purposes. With elucidation of the chemical structures of tetrahydrocannabinol (THC) and cannabidiol (CBD) and with discovery of the human endocannabinoid system, the medical usefulness of cannabinoids has been more intensively explored. While more randomized clinical trials are needed for some medical conditions, other medical disorders, like chronic cancer and neuropathic pain and certain symptoms of multiple sclerosis, have substantial evidence supporting cannabinoid efficacy. While herbal cannabis has not met rigorous FDA standards for medical approval, specific well-characterized cannabinoids have met those standards. Where medical cannabis is legal, patients typically see a physician who "certifies" that a benefit may result. Physicians must consider important patient selection criteria such as failure of standard medical treatment for a debilitating medical disorder. Medical cannabis patients must be informed about potential adverse effects, such as acute impairment of memory, coordination and judgment, and possible chronic effects, such as cannabis use disorder, cognitive impairment, and chronic bronchitis. In addition, social dysfunction may result at work/school, and there is increased possibility of motor vehicle accidents. Novel ways to manipulate the endocannbinoid system are being explored to maximize benefits of cannabinoid therapy and lessen possible harmful effects.

  18. Medical equipment management

    CERN Document Server

    Willson, Keith; Tabakov, Slavik

    2013-01-01

    Know What to Expect When Managing Medical Equipment and Healthcare Technology in Your Organization As medical technology in clinical care becomes more complex, clinical professionals and support staff must know how to keep patients safe and equipment working in the clinical environment. Accessible to all healthcare professionals and managers, Medical Equipment Management presents an integrated approach to managing medical equipment in healthcare organizations. The book explains the underlying principles and requirements and raises awareness of what needs to be done and what questions to ask. I

  19. Choosing Your Medical Specialty

    Science.gov (United States)

    ... the Payment Process Physician Payment Resource Center Reinventing Medical Practice Managing Your Practice CPT® (Current Procedural Terminology) Medicare & Medicaid Private Payer Reform Claims Processing & Practice ...

  20. American Medical Association

    Science.gov (United States)

    ... the Payment Process Physician Payment Resource Center Reinventing Medical Practice Managing Your Practice CPT® (Current Procedural Terminology) Medicare & Medicaid Private Payer Reform Claims Processing & Practice ...

  1. Code of Medical Ethics

    Directory of Open Access Journals (Sweden)

    . SZD-SZZ

    2017-03-01

    Full Text Available Te Code was approved on December 12, 1992, at the 3rd regular meeting of the General Assembly of the Medical Chamber of Slovenia and revised on April 24, 1997, at the 27th regular meeting of the General Assembly of the Medical Chamber of Slovenia. The Code was updated and harmonized with the Medical Association of Slovenia and approved on October 6, 2016, at the regular meeting of the General Assembly of the Medical Chamber of Slovenia.

  2. Organising medication discontinuation

    DEFF Research Database (Denmark)

    Nixon, Michael; Kousgaard, Marius Brostrøm

    2016-01-01

    medication? Methods: Twenty four GPs were interviewed using a maximum variation sample strategy. Participant observations were done in three general practices, for one day each, totalling approximately 30 consultations. Results: The results show that different discontinuation cues (related to the type...... a medication, in agreement with the patients, from a professional perspective. Three research questions were examined in this study: when does medication discontinuation occur in general practice, how is discontinuing medication handled in the GP’s practice and how do GPs make decisions about discontinuing...

  3. Medical Certification System -

    Data.gov (United States)

    Department of Transportation — Provides automated risk-based decision making capability in support of medical certification and clearances processing associated fees and supporting surveillance of...

  4. Energy evaluation

    International Nuclear Information System (INIS)

    Anon.

    2005-01-01

    These 8 charts bring information on with the primary energy consumption, energy indicators, energy bill, prices and electric power, petroleum, natural gas and solid mineral fuels from January 2003 to January 2006. (A.L.B.)

  5. Energy Drinks

    Science.gov (United States)

    ... R S T U V W X Y Z Energy Drinks Share: © Thinkstock Energy drinks are widely promoted as products that increase ... people has been quite effective. Next to multivitamins, energy drinks are the most popular dietary supplement consumed ...

  6. Energy Models

    Science.gov (United States)

    Energy models characterize the energy system, its evolution, and its interactions with the broader economy. The energy system consists of primary resources, including both fossil fuels and renewables; power plants, refineries, and other technologies to process and convert these r...

  7. Energy, tourism

    OpenAIRE

    Frantál, B. (Bohumil)

    2015-01-01

    The chapter provides a general definition of energy and resume the role and environmental impacts of tourism as one of the largest global industries and energy consumers.Then the energy tourism nexus is conceptualized from three perspectives: The first is energy as a driver of tourism. The second is energy as a constraint of tourism. The third is energy as an attraction and object of tourists´interests.

  8. Furthering Medical Education in Texas.

    Science.gov (United States)

    Varma, Surendra K; Jennings, John

    2016-02-01

    Medical education in Texas is moving in the right direction. The Texas Medical Association has been a major partner in advancing medical education initiatives. This special symposium issue on medical education examines residency training costs, the Next Accreditation System, graduate medical education in rural Texas, Texas' physician workforce needs, the current state of education reform, and efforts to retain medical graduates in Texas.

  9. Pandemic Influenza: Perception of Medical Students Medical ...

    African Journals Online (AJOL)

    ... vaccination against H1N1and 31.9% refused joining voluntary work during H1N1 pandemic. Gender, age, marital status and family number were predictors r voluntary work. Conclusion: Defective knowledge and the role of the family are the main factors predispose to further attitude of medical students regarding voluntary ...

  10. Estimation of risks from medical irradiation

    International Nuclear Information System (INIS)

    Persson, B.R.R.

    1983-01-01

    This paper discuss various concepts of quantifying risks from medical irradiation. The expected individual risk from specific medical examination can be derived by estimation the dose-equivalent in different organs and tissues and apply the risk factors recommended for these tissues. A more practical way is to estimate or measure the energy imparted which has been found to correlate quite well with the total risk derived by summing up the risks for the involved tissues. The effective dose-equivalent concept can be used to derive the collective effective dose-equivalent in a population in order to compare the contribution from medical exposure with the contribution from other sources of irradiation in the society. In many countries it is thus shown that medical exposures gives the largest man-made contribution to the population dose

  11. Perangkat Lunak Untuk Analisis Gaya Gelombang Di Laboratorium Lingkungan Dan Energi Laut, Jurusan Teknik Kelautan, Ftk-Its

    Directory of Open Access Journals (Sweden)

    Fendi Hidayat

    2013-09-01

    Full Text Available Laboratorium Lingkungan dan Energi Laut, Jurusan Teknik Kelautan, FTK-ITS sering digunakan untuk pengujian. Salah satunya menguji gaya mooring pada floating breakwater. Hal tersebut menjadi salah satu alasan untuk membuat suatu perangkat lunak dalam membantu dalam proses analisis gaya mooring tersebut. Perangkat lunak yang dibuat berfungsi untuk membantu proses kalibrasi sensor load cell LUB-B 5 to 50 KB dan melakukan analisis gaya gelombang. Metode yang digunakan dalam penelitian ini adalah dengan menggunakan regresi linier, korelasi linier, perhitungan varian, standar deviasi, dan hukum Newton yang kemudian disusun dengan menggunakan Microsoft Visual Studio 2008. Penyusunan perangkat lunak yang bernama FORYS ini memiliki tampilan antarmuka pengguna yang mudah dalam pemakaian. Perangkat lunak yang telah dibuat juga bersifat portable sehingga bisa digunakan di berbagai komputer atau laptop. Hasil pengujian yang telah dilakukan menghasilkan bahwa semakin besar gaya gelombang yang terjadi, maka semakin besar pula tegangan yang terjadi pada tali.  

  12. Nuclear energy and society

    International Nuclear Information System (INIS)

    Baiquni, A.

    1982-01-01

    A great deal of energy will be needed for industrial development. The risks of energy production can be either individual or social in nature. Individual risk occurs in different places and different times to individuals in a certain period of time. Social risk occurs to several people in a time. People tend to refuse a nuclear power plant because of its social risk. This attitude is based more on feelings than reason. In fact radiation from a nuclear power plant is only 0.15% while radiation from medical instruments and from the environment is 99%. From the safety, pollution effect, price, and uses point of view, it can be concluded that nuclear energy is the most appropriate energy to face the future of the nation. (RUW)

  13. Radioactivity and nuclear energy

    International Nuclear Information System (INIS)

    Hoffmann, J.; Kuczera, B.

    2001-05-01

    The terms radioactivity and nuclear energy, which have become words causing irritation in the political sphere, actually represent nothing but a large potential for innovative exploitation of natural resources. The contributions to this publication of the Karlsruhe Research Center examine more closely three major aspects of radioactivity and nuclear energy. The first paper highlights steps in the history of the discovery of radioactivity in the natural environment and presents the state of the art in health physics and research into the effects of exposure of the population to natural or artificial radionuclides. Following contributions focus on: Radiochemical methods applied in the medical sciences (diagnostic methods and devices, therapy). Nuclear energy and electricity generation, and the related safety policies, are an important subject. In this context, the approaches and pathways taken in the field of nuclear science and technology are reported and discussed from the angle of nuclear safety science, and current trends are shown in the elaboration of advanced safety standards relating to nuclear power plant operation and ultimate disposal of radioactive wastes. Finally, beneficial aspects of nuclear energy in the context of a sustainable energy policy are emphasized. In particular, the credentials of nuclear energy in the process of building an energy economy based on a balanced energy mix which combines economic and ecologic advantages are shown. (orig./CB) [de

  14. Medical Virtual Public Services

    Directory of Open Access Journals (Sweden)

    Iulia SURUGIU

    2008-01-01

    Full Text Available The healthcare enterprises are very disconnected. This paper intends to propose a solution that will provide citizens, businesses and medical enterprises with improved access to medical virtual public services. Referred medical services are based on existing national medical Web services and which support medically required services provided by physicians and supplementary health care practitioners, laboratory services and diagnostic procedures, clinics and hospitals’ services. Requirements and specific rules of these medical services are considered, and personalization of user preferences will to be supported. The architecture is based on adaptable process management technologies, allowing for virtual services which are dynamically combined from existing national medical services. In this way, a comprehensive workflow process is set up, allowing for service-level agreements, an audit trail and explanation of the process to the end user. The process engine operates on top of a virtual repository, providing a high-level semantic view of information retrieved from heterogeneous information sources, such as national sources of medical services. The system relies on a security framework to ensure all high-level security requirements are met. System’s architecture is business oriented: it focuses on Service Oriented Architecture - SOA concepts, asynchronously combining Web services, Business Process Management – BPM rules and BPEL standards.

  15. Commercial Crew Medical Ops

    Science.gov (United States)

    Heinbaugh, Randall; Cole, Richard

    2016-01-01

    Provide commercial partners with: center insight into NASA spaceflight medical experience center; information relative to both nominal and emergency care of the astronaut crew at landing site center; a basis for developing and sharing expertise in space medical factors associated with returning crew.

  16. Medications and impaired driving.

    Science.gov (United States)

    Hetland, Amanda; Carr, David B

    2014-04-01

    To describe the association of specific medication classes with driving outcomes and provide clinical recommendations. The MEDLINE and EMBASE databases were searched for articles published from January 1973 to June 2013 on classes of medications associated with driving impairment. The search included outcome terms such as automobile driving, motor vehicle crash, driving simulator, and road tests. Only English-language articles that contained findings from observational or interventional designs with ≥ 10 participants were included in this review. Cross-sectional studies, case series, and case reports were excluded. Driving is an important task and activity for the majority of adults. Some commonly prescribed medications have been associated with driving impairment measured by road performance, driving simulation, and/or motor vehicle crashes. This review of 30 studies identified findings with barbiturates, benzodiazepines, hypnotics, antidepressants, opioid and nonsteroidal analgesics, anticonvulsants, antipsychotics, antiparkinsonian agents, skeletal muscle relaxants, antihistamines, anticholinergic medications, and hypoglycemic agents. Additional studies of medication impact on sedation, sleep latency, and psychomotor function, as well as the role of alcohol, are also discussed. Psychotropic agents and those with central nervous system side effects were associated with measures of impaired driving performance. It is difficult to determine if such associations are actually a result of medication use or the medical diagnosis itself. Regardless, clinicians should be aware of the increased risk of impaired driving with specific classes of medications, educate their patients, and/or consider safer alternatives.

  17. Self-Medication

    African Journals Online (AJOL)

    2012-09-19

    Sep 19, 2012 ... Key words: Self-medication, hazards, pregnant women, Nigeria ... these substances range from protection from witches and witchcrafts, preventing ... is common among pregnant women in our environment. .... Although earlier studies have association self-medication with factors such as self-employment, ...

  18. Medical Practice Makes Perfect

    Science.gov (United States)

    1998-01-01

    Cedaron Medical Inc., was founded in 1990 as a result of a NASA SBIR (Small Business Innovative Research) grant from Johnson Space Center to develop a Hand Testing and Exercise Unit for use in space. From that research came Dexter, a comprehensive workstation that creates a paperless environment for medical data management.

  19. Medication Safety in Psychiatry

    DEFF Research Database (Denmark)

    Sørensen, Ann Lykkegaard

    health care costs. However, PIPs are primarily studied in the elderly. The exclusion of psychiatric patients is common to these studies of medication errors and PIPs. Hence, the aim of this PhD thesis was to investigate the prevalence and potentially clinical consequences of medication errors and PIPs...

  20. Medications for Arrhythmia

    Science.gov (United States)

    ... pharmacist to help you come up with a coding system for your medications that makes them easier to take. Some pharmacists will prepare blister packs for daily or weekly medications. Make an instruction sheet for yourself by taping a sample of each ...

  1. Nigerian Medical Practitioner: Submissions

    African Journals Online (AJOL)

    Author Guidelines. The Nigerian Medical Practitioner, a monthly Journal publishes clinical and research articles in medicine and related fields which are of interest to a large proportion of medical and allied health practitioners. It also publishes miscellaneous articles-hospital administration, business practice, accounting, ...

  2. Nigerian Medical Journal

    African Journals Online (AJOL)

    The Nigerian Medical Journal publishes original articles, reviews, memoranda, reports, case reports, reports of meetings as supplements, letters to the Editor, Association New, book reviews as well as any news of medical relevance. Topics published are of interest to clinicians, researchers, resident doctors, epidemiologists ...

  3. Archives: Malawi Medical Journal

    African Journals Online (AJOL)

    Items 1 - 50 of 72 ... Archives: Malawi Medical Journal. Journal Home > Archives: Malawi Medical Journal. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register · Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives. 1 - 50 of 72 Items, 1 2 > >> ...

  4. Scientific Medical Journal

    African Journals Online (AJOL)

    Scientific Medical Journal: an official journal of Egyptian Medical Education provides a forum for dissemination of knowledge, exchange of ideas, inform of exchange of ideas, information and experience among workers, investigators and clinicians in all disciplines of medicine with emphasis on its treatment and prevention.

  5. Medications (for IBS)

    Medline Plus

    Full Text Available ... J. Lembo, MD, Instructor of Medicine, Harvard Medical School; Division of Gastroenterology, Beth Israel Deaconess Medical Center, ... arises requiring an expert’s care. © Copyright 1998-2018 International Foundation for Functional Gastrointestinal Disorders, Inc. (IFFGD). All ...

  6. Workshop of medical physics

    International Nuclear Information System (INIS)

    1988-01-01

    This event was held in San Carlos de Bariloche, Argentine Republic from 14 th. through 18 th. November, 1988. A great part of the physicians in the area of medical physics participated in this workshop. This volume includes the papers presented at this Workshop of Medical Physics [es

  7. IMTU Medical Journal: Submissions

    African Journals Online (AJOL)

    Studies involving human or animal subjects should be accompanied with an approval from ... The Secretary, IMTU Medical Journal, International Medical & Technological University, PO Box No. ... 3 and 50 for short communication, research articles and case studies but for review articles ... 2nd Ed., New York, McGraw-Hill.

  8. Archives: Continuing Medical Education

    African Journals Online (AJOL)

    Items 51 - 88 of 88 ... Archives: Continuing Medical Education. Journal Home > Archives: Continuing Medical Education. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register · Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives. 51 - 88 of 88 ...

  9. Medication-overuse headache

    DEFF Research Database (Denmark)

    Westergaard, Maria Lurenda; Munksgaard, Signe Bruun; Bendtsen, Lars

    2016-01-01

    and nonmedical treatments, and limiting acute symptomatic medication. Stress reduction and lifestyle interventions may support the change towards rational pain medication use. Support, follow up, and education are needed to help patients through the detoxification period. There is fertile ground for research...

  10. Medical ultrasound imaging

    DEFF Research Database (Denmark)

    Jensen, Jørgen Arendt

    2007-01-01

    The paper gives an introduction to current medical ultrasound imaging systems. The basics of anatomic and blood flow imaging are described. The properties of medical ultrasound and its focusing are described, and the various methods for two- and three-dimensional imaging of the human anatomy...

  11. REMINDER FROM MEDICAL SERVICE

    CERN Multimedia

    Service Médical

    2000-01-01

    For medical problems, we would like to remind all personnel working on the CERN sites, be they staff or from outside firms, that they are welcome at the Infirmary, building 57, ground floor.For information, call the Nurses- on Telephone73802- by electronic mailInfirmary.Service@cern.chMarion.Diedrich@cern.chJanet.Doody@cern.chMireille.Vosdey@cern.chMedical Service

  12. Ebonyi Medical Journal

    African Journals Online (AJOL)

    The journal publishes original research findings, reviews, case reports and letters to the editor in clinical and basic medical sciences to disseminate same to medical doctors, scientists and other health personnel over the world. Vol 11, No 1-2 (2012). DOWNLOAD FULL TEXT Open Access DOWNLOAD FULL TEXT ...

  13. Medically-enhanced normality

    DEFF Research Database (Denmark)

    Møldrup, Claus; Traulsen, Janine Morgall; Almarsdóttir, Anna Birna

    2003-01-01

    Objective: To consider public perspectives on the use of medicines for non-medical purposes, a usage called medically-enhanced normality (MEN). Method: Examples from the literature were combined with empirical data derived from two Danish research projects: a Delphi internet study and a Telebus...

  14. Surgical medical record

    DEFF Research Database (Denmark)

    Bulow, S.

    2008-01-01

    A medical record is presented on the basis of selected linguistic pearls collected over the years from surgical case records Udgivelsesdato: 2008/12/15......A medical record is presented on the basis of selected linguistic pearls collected over the years from surgical case records Udgivelsesdato: 2008/12/15...

  15. Tanzania Medical Journal: Submissions

    African Journals Online (AJOL)

    The Tanzania Medical Journal is a multi – disciplinary journal published two times a year in March - June and September – December. ... To achieve its objectives the journal invites papers on original scientific research, short communications, case reports and letters to the editor, in any branch of medical science. Original ...

  16. Implications of Medical Tourism.

    Science.gov (United States)

    Cesario, Sandra K

    2018-06-01

    Medical tourism is an emerging industry that facilitates travel to another country for people who seek medical, surgical, or dental care that is unavailable or more affordable than in their home countries. Rapid advances in electronic communication and the ease of international travel have fueled the growth of this industry. More than half of medical travelers are women, especially for services related to cosmetic or reproductive conditions. Medical tourism creates both opportunities and challenges for nurses and other health care providers. Consumers' increased access to the global health care market necessitates the development of a structure that shapes the medical tourism industry and addresses evolving ethical, political, and human rights concerns related to this industry. Copyright © 2018 AWHONN. Published by Elsevier Inc. All rights reserved.

  17. Soft energy vs nuclear energy

    International Nuclear Information System (INIS)

    Ando, Yoshio

    1981-01-01

    During the early 1960s, a plentiful, inexpensive supply of petroleum enabled Japanese industry to progress rapidly; however, almost all of this petroleum was imported. Even after the first oil crisis of 1973, the recent annual energy consumption of Japan is calculated to be about 360 million tons in terms of petroleum, and actual petroleum forms 73% of total energy. It is necessary for Japan to reduce reliance on petroleum and to diversify energy resources. The use of other fossil fuels, such as coal, LNG and LPG, and hydraulic energy, is considered as an established alternative. In this presentation, the author deals with new energy, namely soft energy and nuclear energy, and discusses their characteristics and problems. The following kinds of energy are dealt with: a) Solar energy, b) Geothermal energy, c) Ocean energy (tidal, thermal, wave), d) Wind energy, e) Biomass energy, f) Hydrogen, g) Nuclear (thermal, fast, fusion). To solve the energy problem in future, assiduous efforts should be made to develop new energy systems. Among them, the most promising alternative energy is nuclear energy, and various kinds of thermal reactor systems have been developed for practical application. As a solution to the long-term future energy problem, research on and development of fast breeder reactors and fusion reactors are going on. (author)

  18. Managed medical education?

    Science.gov (United States)

    Hafferty, F W

    1999-09-01

    The forces of rationality and commodification, hallmarks of the managed care revolution, may soon breach the walls of organized medical education. Whispers are beginning to circulate that the cost of educating future physicians is too high. Simultaneously, managed care companies are accusing medical education of turning out trainees unprepared to practice in a managed care environment. Changes evident in other occupational and service delivery sectors of U.S. society as diverse as pre-college education and prisons provide telling insights into what may be in store for medical educators. Returning to academic medicine, the author reflects that because corporate managed care is already established in teaching hospitals, and because managed research (e.g., corporate-sponsored and -run drug trials, for-profit drug-study centers, and contract research organizations) is increasing, managed medical education could become a reality as well. Medical education has made itself vulnerable to the intrusion of corporate rationalizers because it has failed to professionalism at core of its curricula-something only it is able to do--and instead has focused unduly on the transmission of esoteric knowledge and core clinical skills, a process that can be carried out more efficiently, more effectively, and less expensively by other players in the medical education marketplace such as Kaplan, Compass, or the Princeton Review. The author explains why reorganizing medical education around professional values is crucial, why the AAMC's Medical School Objectives Project offers guidance in this area, why making this change will be difficult, and why medical education must lead in establishing how to document the presence and absence of such qualities as altruism and dutifulness and the ways that appropriate medical education can foster these and similar core competencies. "Anything less and organized medicine will acknowledged... that it has abandoned its social contract and entered the

  19. MEDICAL LAW AND ETHICS

    Directory of Open Access Journals (Sweden)

    Sunčica Ivanović

    2013-09-01

    Full Text Available The subject of interest in this article is the importance of knowing and connecting medical ethics and medical law for the category of health workers. The author believes that knowledge of bioethics which as a discipline deals with the study of ethical issues and health care law as a legal discipline, as well as medical activity in general, result in the awareness of health professionals of human rights, and since the performance of activities of health workers is almost always linked to the question of life and death, then the lack of knowledge of basic legal acts would not be justified at all. The aim of the paper was to present the importance of medical ethics and medical law among the medical staff. A retrospective analysis of the medical literature available on the indexed base KOBSON for the period 2005-2010 was applied. Analysis of all work leads to the conclusion that the balance between ethical principles and knowledge of medical law, trust and cooperation between the two sides that appear over health care can be considered a goal that every health care worker should strive for. This study supports the attitude that lack of knowledge and non-compliance with the ethical principles and medical law when put together can only harm the health care worker. In a way, this is the message to health care professionals that there is a need for the adoption of ethical principles and knowledge of medical law, because the most important position of all health workers is their dedication to the patient as a primary objective and the starting point of ethics.

  20. Energy Theater

    Science.gov (United States)

    Daane, Abigail R.; Wells, Lindsay; Scherr, Rachel E.

    2014-01-01

    Energy Theater is a dynamic, full-body activity that engages all students in representing the flow of energy in various phenomena, such as a light bulb burning steadily or a refrigerator cooling food. In Energy Theater, each participant acts as a unit of energy that has one form at a time. Regions on the floor correspond to objects in a physical…