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Sample records for developed dosimetric grade

  1. ARDENT to develop advanced dosimetric techniques

    CERN Multimedia

    Antonella Del Rosso

    2012-01-01

    Earlier this week, the EU-supported Marie Curie training network ARDENT kicked off at a meeting held at CERN. The overall aim of the project is the development of advanced instrumentation for radiation dosimetry. The applications range from radiation measurements around particle accelerators, onboard commercial flights and in space, to the characterization of radioactive waste and medicine, where accurate dosimetry is of vital importance.   The ARDENT (Advanced Radiation Dosimetry European Network Training) project is both a research and a training programme, which aims at developing new dosimetric techniques while providing 15 Early-Stage Researchers (ESR) with state-of-the-art training. The project, coordinated by CERN, is funded by the European Union with a contribution of about 3.9 million euros over four years. The ARDENT initiative will focus on three main technologies: gas detectors, in particular Gas Electron Multipliers (GEM) and Tissue Equivalent Proportional Counters (TEPC); solid stat...

  2. Intensity-modulated radiotherapy in high-grade gliomas: Clinical and dosimetric results

    International Nuclear Information System (INIS)

    Narayana, Ashwatha; Yamada, Josh; Berry, Sean; Shah, Priti B.S.; Hunt, Margie; Gutin, Philip H.; Leibel, Steven A.

    2006-01-01

    Purpose: To report preliminary clinical and dosimetric data from intensity-modulated radiotherapy (IMRT) for malignant gliomas. Methods and Materials: Fifty-eight consecutive high-grade gliomas were treated between January 2001 and December 2003 with dynamic multileaf collimator IMRT, planned with the inverse approach. A dose of 59.4-60 Gy at 1.8-2.0 Gy per fraction was delivered. A total of three to five noncoplanar beams were used to cover at least 95% of the target volume with the prescription isodose line. Glioblastoma accounted for 70% of the cases, and anaplastic oligodendroglioma histology (pure or mixed) was seen in 15% of the cases. Surgery consisted of biopsy only in 26% of the patients, and 80% received adjuvant chemotherapy. Results: With a median follow-up of 24 months, 85% of the patients have relapsed. The median progression-free survival time for anaplastic astrocytoma and glioblastoma histology was 5.6 and 2.5 months, respectively. The overall survival time for anaplastic glioma and glioblastoma was 36 and 9 months, respectively. Ninety-six percent of the recurrences were local. No Grade IV/V late neurologic toxicities were noted. A comparative dosimetric analysis revealed that regardless of tumor location, IMRT did not significantly improve target coverage compared with three-dimensional planning. However, IMRT resulted in a decreased maximum dose to the spinal cord, optic nerves, and eye by 16%, 7%, and 15%, respectively, owing to its improved dose conformality. The mean brainstem dose also decreased by 7%. Intensity-modulated radiotherapy delivered with a limited number of beams did not result in an increased dose to the normal brain. Conclusions: It is unlikely that IMRT will improve local control in high-grade gliomas without further dose escalation compared with conventional radiotherapy. However, it might result in decreased late toxicities associated with radiotherapy

  3. Rectal bleeding after hypofractionated radiotherapy for prostate cancer: Correlation between clinical and dosimetric parameters and the incidence of grade 2 or worse rectal bleeding

    International Nuclear Information System (INIS)

    Akimoto, Tetsuo; Muramatsu, Hiroyuki; Takahashi, Mitsuhiro; Saito, Jun-ichi; Kitamoto, Yoshizumi; Harashima, Koichi; Miyazawa, Yasushi; Yamada, Masami; Ito, Kazuto; Kurokawa, Kouhei; Yamanaka, Hidetoshi; Nakano, Takashi; Mitsuhashi, Norio; Niibe, Hideo

    2004-01-01

    Purpose: To investigate the incidence and severity of rectal bleeding after high-dose hypofractionated radiotherapy (RT) for prostate cancer, and to explore the factors affecting the incidence of Grade 2 or worse rectal bleeding. Methods and materials: The data of 52 patients who had been treated by external beam RT for localized prostate cancer between 1999 and 2002 were analyzed. All the patients had received hypofractionated external beam RT to a total dose of 69 Gy in 3-Gy fractions, three fractions weekly. The clinical and dosimetric factors affecting the incidence of Grade 2 or worse late rectal bleeding were analyzed by univariate and multivariate analyses. The effect of the percentage of the whole rectal volume receiving 30%, 50%, 80%, and 90% of the prescribed radiation dose (V 30 , V 50 , V 80 , and V 90 , respectively) on the incidence of rectal bleeding was evaluated. Results: Of the 52 patients, 13 (25%) developed Grade 2 or worse rectal bleeding. One patient who needed laser coagulation and blood transfusion for the treatment of rectal bleeding was classified as having Grade 3 rectal bleeding. The median time to the development of Grade 2 or worse rectal bleeding was 11 months. The results of the univariate analysis revealed that the presence of a history of diabetes mellitus (p 30 ≥ 60%, V 50 ≥ 40% (p 80 ≥ 25%, and V 90 ≥ 15% (p < 0.001) were statistically significant risk factors for the occurrence of Grade 2 or worse rectal bleeding. The results of the multivariate analysis revealed that a history of diabetes mellitus was the most statistically significant risk factor for the occurrence of rectal bleeding after hypofractionated RT for prostate cancer (p < 0.05). Conclusion: A history of diabetes mellitus was the most statistically significant risk factor for the occurrence of Grade 2 or worse rectal bleeding after high-dose hypofractionated RT, although dosimetric factors were also closely associated with the risk of rectal bleeding

  4. Clinical and Dosimetric Predictors of Acute Severe Lymphopenia During Radiation Therapy and Concurrent Temozolomide for High-Grade Glioma

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Jiayi, E-mail: jhuang@radonc.wustl.edu [Department of Radiation Oncology, Washington University School of Medicine, St Louis, Missouri (United States); DeWees, Todd A.; Badiyan, Shahed N.; Speirs, Christina K.; Mullen, Daniel F.; Fergus, Sandra [Department of Radiation Oncology, Washington University School of Medicine, St Louis, Missouri (United States); Tran, David D.; Linette, Gerry; Campian, Jian L. [Division of Medical Oncology, Department of Medicine, Washington University School of Medicine, St Louis, Missouri (United States); Chicoine, Michael R.; Kim, Albert H.; Dunn, Gavin [Department of Neurosurgery, Washington University School of Medicine, St Louis, Missouri (United States); Simpson, Joseph R.; Robinson, Clifford G. [Department of Radiation Oncology, Washington University School of Medicine, St Louis, Missouri (United States)

    2015-08-01

    Purpose: Acute severe lymphopenia (ASL) frequently develops during radiation therapy (RT) and concurrent temozolomide (TMZ) for high-grade glioma (HGG) and is associated with decreased survival. The current study was designed to identify potential predictors of ASL, with a focus on actionable RT-specific dosimetric parameters. Methods and Materials: From January 2007 to December 2012, 183 patients with HGG were treated with RT+TMZ and had available data including total lymphocyte count (TLC) and radiation dose-volume histogram parameters. ASL was defined as TLC of <500/μL within the first 3 months from the start of RT. Stepwise logistic regression analysis was used to determine the most important predictors of ASL. Results: Fifty-three patients (29%) developed ASL. Patients with ASL had significantly worse overall survival than those without (median: 12.5 vs 20.2 months, respectively, P<.001). Stepwise logistic regression analysis identified female sex (odds ratio [OR]: 5.30; 95% confidence interval [CI]: 2.46-11.41), older age (OR: 1.05; 95% CI: 1.02-1.09), lower baseline TLC (OR: 0.92; 95% CI: 0.87-0.98), and higher brain volume receiving 25 Gy (V{sub 25Gy}) (OR: 1.03; 95% CI: 1.003-1.05) as the most significant predictors for ASL. Brain V{sub 25Gy} <56% appeared to be the optimal threshold (OR: 2.36; 95% CI: 1.11-5.01), with an ASL rate of 38% versus 20% above and below this threshold, respectively (P=.006). Conclusions: Female sex, older age, lower baseline TLC, and higher brain V{sub 25Gy} are significant predictors of ASL during RT+TMZ therapy for HGG. Maintaining the V{sub 25Gy} of brain below 56% may reduce the risk of ASL.

  5. Personal dosimetric monitoring in Ukraine: current status and further development

    International Nuclear Information System (INIS)

    Chumak, V. V.; Musijachenkom, A. V.; Boguslavskaya, A. I.

    2003-01-01

    Presently Ukraine has mixed system for dosimetric monitoring. Nuclear power plants and some major nuclear facilities have their own dosimetry services, which are responsible for regular dosimetric monitoring of workers. Rest of occupationally exposed persons is monitored by dosimetry laboratories affiliated to the territorial authorities for sanitary and epidemiology supervision. In 2002-2003 Ukrainian Ministry of Health performed survey of the status of dosimetric monitoring and inventory of critical groups requiring such monitoring. Dosimetry services in Ukraine cover about 38,000 occupationally exposed workers, including 9,100 medical professionals, 16,400 employees of 5 nuclear power plants and ca.12,400 workers dealing with other sources of occupational exposure (industry, research). Territorial dosimetry services operate in 13 of 24 regions of Ukraine, using DTU-01 manual TLD readers produced with one exception in 1988-1990. The coverage of critical groups by dosimetric monitoring is variable and ranges from 38% to 100% depending on the region. Personnel of nuclear power plants (about 16,400 workers) is monitored by their own dosimetry services achieving absolute coverage of the main staff and temporary workers. Current inadequate status of dosimetric monitoring infrastructure in Ukraine demands an urgent elaboration of the united state system for monitoring and recording of individual doses. The proposed plan would allows to bring dosimetry infrastructure in Ukraine to the modern state which would be compatible with existing and future European and international radiation protection networks. Unitary structure of Ukraine, strong administrative command and good communications between regions of the country are positive factors in favour of efficient implementation of the proposed plan. Deficiencies are associated with limited funding of this effort. (authors)

  6. Development of the Nation-Wide Dosimetric Monitoring Network in Ukraine

    International Nuclear Information System (INIS)

    Chumak, V.; Boguslavskaya, A.; Musijachenko, A.

    2004-01-01

    Development of the nation-wide network for monitoring and registration of individual doses is being in progress in Ukraine. The need for urgent action is caused by the fact, that despite wide use of nuclear energy and radiation sources in industry and medicine, there is no centralized dose accounting system in Ukraine, existing dosimetry services operate obsolete manual TLD readers and no methodological unity is observed by the dosimetry services. Presently the mixed dosimetric monitoring is practiced in Ukraine. Nuclear power plants and some major nuclear facilities have their own dosimetry services responsible for dosimetric monitoring of workers. Rest of occupationally exposed persons is monitored by territorial dosimetry laboratories affiliated to sanitary and epidemiology supervision bodies. In total these services cover about 38,000 occupationally exposed workers, including 5,500 in medicine, 16,400 employees of five nuclear power plants and about 16,000 workers dealing with other sources of occupational exposure (industry, research, military). It is prescribed by the governmental decree that three-level united state system assigned to covering all aspects of efficient dosimetric monitoring should be established. The tasks of the system, in particular, are: securing methodical unity of individual dosimetric monitoring; scientific and methodological guidance of individual dosimetric control; procurement of common technical policy regarding nomenclature and operation of instrumentation; implementation of quality assurance programs; development and support of information infrastructure for logging, storage and access to data on individual dosimetric monitoring, in particular - keeping the national registry of individual doses; training and certification of personnel engaged in the system of individual dosimetric monitoring. In its development, the national system will be guided by international experience and will be established according to the best practices

  7. Dosimetric advantages of proton therapy over conventional radiotherapy with photons in young patients and adults with low-grade glioma

    International Nuclear Information System (INIS)

    Harrabi, S.B.; Herfarth, K.; Bougatf, N.; Mohr, A.; Haberer, T.; Combs, S.E.; Debus, J.; Adeberg, S.

    2016-01-01

    Low-grade glioma (LGG) is a very common brain tumor in pediatric patients typically associated with a very good prognosis. This prognosis makes it imperative that the risk of long-term treatment-related side effects be kept at an absolute minimum. Proton therapy (PRT) provides a radiation technique that has the potential to further reduce the genesis of radiogenic impairment. We retrospectively assessed 74 patients with LGG who underwent PRT. Conventional three-dimensional photon and PRT plans were generated after contouring structures of neurogenesis, crucial neuronal structures, and areas susceptible to secondary malignancies. Target volume coverage was evaluated using the homogeneity index (HI) and inhomogeneity coefficient (IC). Results were compared using the Wilcoxon-signed rank test, with p < 0.05 being statistically significant. Target volume coverage was comparable for the photon and proton plans. Overall, we could show an essential reduction in maximal, mean, and integral doses in critical neurologic structures, areas of neurogenesis, and structures of neurocognitive function. The study indicated specifically how contralaterally located structures could be spared with PRT. PRT is a highly conformal radiation technique offering superior dosimetric advantages over conventional radiotherapy by allowing significant dose reduction for organs at risk (OAR) that are essential for neurologic function, neurocognition, and quality of life, thus demonstrating the potential of this technique for minimizing long-term sequelae. (orig.) [de

  8. A dosimetric comparison of four treatment planning methods for high grade glioma

    Directory of Open Access Journals (Sweden)

    Miller Robert W

    2009-10-01

    Full Text Available Abstract Background High grade gliomas (HGG are typically treated with a combination of surgery, radiotherapy and chemotherapy. Three dimensional (3D conformal radiotherapy treatment planning is still the main stay of treatment for these patients. New treatment planning methods suggest better dose distributions and organ sparing but their clinical benefit is unclear. The purpose of the current study was to compare normal tissue sparing and tumor coverage using four different radiotherapy planning methods in patients with high grade glioma. Methods Three dimensional conformal (3D, sequential boost IMRT, integrated boost (IB IMRT and Tomotherapy (TOMO treatment plans were generated for 20 high grade glioma patients. T1 and T2 MRI abnormalities were used to define GTV and CTV with 2 and 2.5 cm margins to define PTV1 and PTV2 respectively. Results The mean dose to PTV2 but not to PTV1 was less then 95% of the prescribed dose with IB and IMRT plans. The mean doses to the optic chiasm and the ipsilateral globe were highest with 3D plans and least with IB plans. The mean dose to the contralateral globe was highest with TOMO plans. The mean of the integral dose (ID to the brain was least with the IB plan and was lower with IMRT compared to 3D plans. The TOMO plans had the least mean D10 to the normal brain but higher mean D50 and D90 compared to IB and IMRT plans. The mean D10 and D50 but not D90 were significantly lower with the IMRT plans compared to the 3D plans. Conclusion No single treatment planning method was found to be superior to all others and a personalized approach is advised for planning and treating high-grade glioma patients with radiotherapy. Integral dose did not reflect accurately the dose volume histogram (DVH of the normal brain and may not be a good indicator of delayed radiation toxicity.

  9. Dosimetric systems developed in Brazil for the radiation processes quality control

    International Nuclear Information System (INIS)

    Galante, Ana Maria Sisti; Campos, Leticia Lucente

    2011-01-01

    In order to apply new technologies to the industrial processing of materials aiming economy, efficiency, speed and high quality, ionizing radiation has been used in medicine, archaeology, chemistry, food preservation and other areas. For this reason, the dosimetry area looks for improve current dosimeters and develop new materials for application on quality control of these processes. In Brazil, the research in the dosimetry area occurs with great speed providing many different dosimetric systems. The chemical dosimetry is the most used technique in routine dosimetry, which requires fast and accurate responses. This technique involves determination of absorbed dose by measuring chemical changes radiation induced in the materials. Different dosimetric systems were developed at IPEN for application on radiation process quality and all of them present excellent results; the low cost of these materials allows a more effective dose control, therefore, a larger area or volume can be monitored. (author).

  10. Dosimetric systems developed in Brazil for the radiation processes quality control

    Energy Technology Data Exchange (ETDEWEB)

    Galante, Ana Maria Sisti; Campos, Leticia Lucente, E-mail: sgalante@ipen.b, E-mail: lcrodri@ipen.b [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2011-07-01

    In order to apply new technologies to the industrial processing of materials aiming economy, efficiency, speed and high quality, ionizing radiation has been used in medicine, archaeology, chemistry, food preservation and other areas. For this reason, the dosimetry area looks for improve current dosimeters and develop new materials for application on quality control of these processes. In Brazil, the research in the dosimetry area occurs with great speed providing many different dosimetric systems. The chemical dosimetry is the most used technique in routine dosimetry, which requires fast and accurate responses. This technique involves determination of absorbed dose by measuring chemical changes radiation induced in the materials. Different dosimetric systems were developed at IPEN for application on radiation process quality and all of them present excellent results; the low cost of these materials allows a more effective dose control, therefore, a larger area or volume can be monitored. (author).

  11. Researches, development and characterization of dosimetric materials for monitoring in irradiation processes with high doses

    International Nuclear Information System (INIS)

    Galante, Ana Maria Sisti

    2003-01-01

    Dosimetric materials that can be produced in Brazil with material acquired in the national market to replace the imported dosimeters used in radiation processing were developed in this work. Mixtures of potassium nitrate and sensitizers compounds as manganese dioxide, barium nitrate and potassium bromide were prepared in the pellet form. Dosimetric characteristics such as dose-response useful range, sensitivity, environmental conditions and dose rate influences were evaluated in 60 Co gamma radiation fields. Dyed polymethylmethacrylate detectors were also produced and its dosimetric characteristics were evaluated. The main characteristics evaluated in this case were: dose response useful range sensitivity, environmental conditions, dose rate influences and radiation energy dependence in gamma radiation fields and accelerated electrons beam of 0.8 to 1.5 MeV. The applied analytic technique was spectrophotometry. The calibration was performed in the irradiation facilities belonging to IPEN and certified by the International Atomic Energy Agency by means of the program IDAS (International Dose Assurance Service ) using the Fricke dosimeter. The mixture of potassium nitrate and manganese dioxide presented the best results and a wide dose range between 200 and 600 kGy. The response of the developed polymethylmethacrylate detectors are similar to the imported detectors and the dose range is characteristic to each detector and depends on the dye added in its formulation. (author)

  12. Dosimetric advantages of proton therapy over conventional radiotherapy with photons in young patients and adults with low-grade glioma

    Energy Technology Data Exchange (ETDEWEB)

    Harrabi, S.B.; Herfarth, K. [Heidelberg Institute of Radiation Oncology (HIRO), Heidelberg (Germany); Heidelberg Ion-Beam Therapy Center (HIT), Heidelberg (Germany); University Hospital Heidelberg, Dept. of Radiation Oncology, Heidelberg (Germany); Bougatf, N. [Heidelberg Institute of Radiation Oncology (HIRO), Heidelberg (Germany); University Hospital Heidelberg, Dept. of Radiation Oncology, Heidelberg (Germany); German Cancer Research Center (DKFZ), Department of Medical Physics in Radiation Oncology, Heidelberg (Germany); Mohr, A. [Heidelberg Institute of Radiation Oncology (HIRO), Heidelberg (Germany); University Hospital Heidelberg, Dept. of Radiation Oncology, Heidelberg (Germany); Haberer, T. [Heidelberg Institute of Radiation Oncology (HIRO), Heidelberg (Germany); Heidelberg Ion-Beam Therapy Center (HIT), Heidelberg (Germany); Combs, S.E. [Helmholtz Zentrum Muenchen, Department of Radiation Sciences (DRS), Institute of Innovative Radiotherapy (iRT), Oberschleissheim (Germany); Deutsches Konsortium fuer Translationale Krebsforschung (dktk), Partner Site Munich, Munich (Germany); Debus, J.; Adeberg, S. [Heidelberg Institute of Radiation Oncology (HIRO), Heidelberg (Germany); Heidelberg Ion-Beam Therapy Center (HIT), Heidelberg (Germany); University Hospital Heidelberg, Dept. of Radiation Oncology, Heidelberg (Germany); German Cancer Research Center (DKFZ), Clinical Cooperation Unit Radiation Oncology, Heidelberg (Germany)

    2016-11-15

    Low-grade glioma (LGG) is a very common brain tumor in pediatric patients typically associated with a very good prognosis. This prognosis makes it imperative that the risk of long-term treatment-related side effects be kept at an absolute minimum. Proton therapy (PRT) provides a radiation technique that has the potential to further reduce the genesis of radiogenic impairment. We retrospectively assessed 74 patients with LGG who underwent PRT. Conventional three-dimensional photon and PRT plans were generated after contouring structures of neurogenesis, crucial neuronal structures, and areas susceptible to secondary malignancies. Target volume coverage was evaluated using the homogeneity index (HI) and inhomogeneity coefficient (IC). Results were compared using the Wilcoxon-signed rank test, with p < 0.05 being statistically significant. Target volume coverage was comparable for the photon and proton plans. Overall, we could show an essential reduction in maximal, mean, and integral doses in critical neurologic structures, areas of neurogenesis, and structures of neurocognitive function. The study indicated specifically how contralaterally located structures could be spared with PRT. PRT is a highly conformal radiation technique offering superior dosimetric advantages over conventional radiotherapy by allowing significant dose reduction for organs at risk (OAR) that are essential for neurologic function, neurocognition, and quality of life, thus demonstrating the potential of this technique for minimizing long-term sequelae. (orig.) [German] Niedriggradige Gliome (LGG) zaehlen zu den haeufigsten Hirntumoren im Kindesalter und sind ueblicherweise mit einer sehr guten Prognose vergesellschaftet. Es gilt daher, das Risiko fuer therapieassoziierte Spaetfolgen so gering wie moeglich zu halten. Mit der Protonenbestrahlung steht eine Bestrahlungsmodalitaet zur Verfuegung, mit der das Auftreten radiogener Spaetfolgen im Vergleich zu konventionellen Bestrahlungstechniken

  13. Development and dosimetric evaluation of radiochromic PCDA vesicle gel dosimeters

    International Nuclear Information System (INIS)

    Sun, P.; Fu, Y.C.; Hu, J.; Hao, N.; Huang, W.; Jiang, B.

    2016-01-01

    The gel dosimeter has the unique capacity in recording radiation dose distribution in three dimensions (3D), which has the specific advantages in dosimetry measurements where steep dose gradients exist, such as in intensity-modulated radiation therapy (IMRT), brachytherapy and so on. Some 3D dosimeters, such as Fricke gel dosimeters, polymer gel dosimeters, the PRESAGE plastic dosimeters and micelle gel dosimeters have appeared recently. However, there are several disadvantages of these 3D dosimeters limit their application in radiotherapy dose verification. In this study, a novel radiochromic gel dosimeter for 3D dose verification of radiotherapy was developed by dispersing nanovesicles self-assembled by 10,12-pentacosadiynoic acid (PCDA) into the tissue equivalence gel matrix. The characteristics of radiochromic PCDA vesicle gel dosimeters were evaluated. The results indicate that these radiochromic gel dosimeters have good linear dose response to X-ray irradiation in the dose range of 2–100 Gy. In addition, the radiochromic gel dosimeters breakthrough the limitations of the existing gel dosimeters such as diffusion effect, post-radiation effect, and poor forming ability. The response of the gel dosimeter does not show any dose rate dependence, energy dependence and temperature effect, and there was no obvious difference in the gel response between single and cumulative dose of fractional irradiation. Hence, the radiochromic PCDA vesicle gel dosimeters developed in this study could be generally applied to 3D dose verification in radiotherapy. - Highlights: • A novel radiochromic gel dosimeter was developed by dispersing PCDA nanovesicles into the tissue equivalence gel matrix. • This nanovesicle overcomes the dose image blurring caused by the diffusion of monomer molecules. • This nanovesicle limits the polymer chain growth, so as to reduce the post-radiation effect. • The gel matrixes possess excellent tissue equivalence and elastic strength, which

  14. Development of an algorithm simulator of the planar radioactive source for dosimetric evaluations in accidents with radiopharmaceuticals used in nuclear medicine

    International Nuclear Information System (INIS)

    Claudino, Gutemberg L. Sales; Vieira, Jose Wilson; Leal Neto, Viriato; Lima, Fernando R. Andrade

    2013-01-01

    Objective of this work is to develop an algorithm simulator for dosimetric evaluation of accidents that may happen in Nuclear Medicine using PDF NT (Probability Density Functions). A software was developed using C# and WPF technology, in the integrated environment of Microsoft Visual Studio to organize and present the dosimetric results

  15. Development of an algorithm simulator of the planar radioactive source for dosimetric evaluations in accidents with radiopharmaceuticals used in nuclear medicine

    Energy Technology Data Exchange (ETDEWEB)

    Claudino, Gutemberg L. Sales; Vieira, Jose Wilson; Leal Neto, Viriato, E-mail: berg2020@hotmail.com [Instituto Federal de Educacao, Ciencia e Tecnologia de Pernambuco (IFPE), Recife, PE (Brazil); Lima, Fernando R. Andrade, E-mail: falima@cnen.gov.br [Centro Regional de Ciencias Nucleares do Nordeste (CRCN-NE/CNEN-PE), Recife, PE (Brazil)

    2013-07-01

    Objective of this work is to develop an algorithm simulator for dosimetric evaluation of accidents that may happen in Nuclear Medicine using PDF NT (Probability Density Functions). A software was developed using C# and WPF technology, in the integrated environment of Microsoft Visual Studio to organize and present the dosimetric results.

  16. Development of a multi-diode dosimetric system for quality assurance in radiotherapy equipment

    International Nuclear Information System (INIS)

    Santos, Gelson Pinto dos

    2002-01-01

    A multi-diode dosimetric system was developed and tested for quality control of photon and electron beams as used in radiotherapy. The following tests were done: repeatability and reproducibility, linearity, degradation with dose, energy dependence, dose rate dependence and response with the field size. These results were compared with the response of ionization chambers. For the most tests, the multi-diode system presented similar response of it, which demonstrated its viability for clinical dosimetry use. A quality assurance program for a multi-beam accelerator was proposed as an example of its application in a routine use for a radiotherapy service. Besides its practicability of using, the system presents the advantage of low cost, compared to imported system in use nowadays. (author)

  17. Software development for statistical handling of dosimetric and epidemiological data base

    International Nuclear Information System (INIS)

    Amaro, M.

    1990-01-01

    The dose records from different groups of occupationally exposed workers are available in a computerized data base whose main purpose is the individual dose follow-up. Apart from this objective, such a dosimetric data base can be useful to obtain statistical analysis. The type of statistical n formation that can be extracted from the data base may aim to attain mainly two kinds of objectives: - Individual and collective dose distributions and statistics. -Epidemiological statistics. The report describes the software developed to obtain the statistical reports required by the Regulatory Body, as well as any other type of dose distributions or statistics to be included in epidemiological studies A Users Guide for the operators who handle this software package, and the codes listings, are also included in the report. (Author) 2 refs

  18. Development of a dosimetric system for emergency situation involving person of the public

    International Nuclear Information System (INIS)

    Costa, Zelia Maria da

    1999-01-01

    A dosimetric system was developed for emergency situation based on electron spin resonance spectrometry (E.S.R.) and some materials such as tooth enamel, bovine bone, CaCO 3 and sugar as detector. The purpose of this work was to find common materials, which are both reliable and sensitive and make possible quickly to assess the absorbed dose. The research includes the collection and preparation of samples, the evaluation, treatment and interpretation of ESR signal and the procedure for dose reconstruction. The calibration of the dosemeter was performed using gamma radiation from a Co-60 source. The results obtained confirm the variability of the use of this system in case of an accident. (author)

  19. Software development for statistical handling of dosimetric and epidemiological data base

    International Nuclear Information System (INIS)

    Amaro, M.

    1990-01-01

    The dose records from different group of occupationally exposed workers are available in a computerized data base whose main purpose is the individual dose follow-up. Apart from this objective, such a dosimetric data base can be useful to obtain statistical analysis. The type of statistical information that can be extracted from the data base may aim to attain mainly two kinds of obsectives: - Individual and collective dose distributions and statistics. - Epidemiological statistics. The report describes the software developed to obtain the statistical reports required by the Regulatory Body, as well as any other type of dose distributions or statistics to be included in epidsemiological studies. A Users Guide for the operators who handle this sofware package, and the codes listings, are also included in the report. (Author)

  20. Development of a dosimetric system for 90Sr + 90Y betatherapy applicators

    International Nuclear Information System (INIS)

    Coelho, Talita Salles

    2010-01-01

    The 90 Sr+ 90 Y applicators, used in betatherapy for prevention of keloids and pterigium, are imported and many times their dosimetric features are shown only in an illustrated form by the manufacturers. The exhaustive routine of the medical physicists in the clinic do not make possible the accomplishment of procedures for the confirmation of these parameters. This work presents the development of a methodology for the dosimetry of 90 Sr+ 90 Y betatherapy applicators. The Monte Carlo code MCNP5 was used for the simulation of the percentage depth dose curves and dose distribution profiles produced by these applicators. The experimental measurements of the radial and axial radiation attenuation, have been done with a mini-extrapolation chamber, thermoluminescent dosimeters and radiographic films. The experimental results have been compared with the simulated values. Both percentage depth dose curves and the radial dose profiles, the theoretical and the experimental ones, have presented good agreement, which may validate the use of the MCNP5 for these simulations, confirming the viability of the usage of this method in procedures of beta emitter sources dosimetry. (author)

  1. Development of a personalized dosimetric tool for radiation protection in case of internal contamination and targeted radiotherapy in nuclear medicine

    International Nuclear Information System (INIS)

    Chiavassa, S.

    2005-12-01

    Current internal dosimetric estimations are based on the M.I.R.D. formalism and used standard mathematical models. These standard models are often far from a given patient morphology and do not allow to perform patient-specific dosimetry. The aim of this study was to develop a personalized dosimetric tool, which takes into account real patient morphology, composition and densities. This tool, called O.E.D.I.P.E., a French acronym of Tool for the Evaluation of Personalized Internal Dose, is a user-friendly graphical interface. O.E.D.I.P.E. allows to create voxel-based patient-specific geometries and associates them with the M.C.N.P.X. Monte Carlo code. Radionuclide distribution and absorbed dose calculation can be performed at the organ and voxel scale. O.E.D.I.P.E. can be used in nuclear medicine for targeted radiotherapy and in radiation protection in case of internal contamination. (author)

  2. Developing Middle Grades Students' MP3

    Science.gov (United States)

    Tassell, Janet; Stobaugh, Rebecca; Sheffield, Linda

    2011-01-01

    Middle grades are a critical time for capturing the interest and imagination and developing the potential of mathematically promising students. This is a time for students to make sense of mathematics, build a solid foundation and enthusiasm, and set the course for the highest levels of mathematics in the future. This is a time to explore their…

  3. Development of a dosimetric system for dental X-ray equipment quality control

    International Nuclear Information System (INIS)

    Melo, Francisco Almeida de

    2002-08-01

    An electronic instrument with digital readout was designed and constructed to provide fast, simple and non-invasive measurements of X-ray dental equipment parameters. This instrument is capable of evaluating the entrance dose, exposure time, tube voltage (kVp) and beam filtration. It consists of a set of five photodiodes connected each one in the photocurrent mode to the input of a designed integrating electrometer. Three of the detectors are fixed under aluminium filters with different thicknesses, one is fixed under a 0.3 mm copper filter and the other has no filtration. The readings of the three detectors under aluminium filters and of the bare detector permit the determination of the half-value layer, which is used to calculate the beam filtration. The ratio between the readings of the detector below the copper filter and the one without filtration is used to determine the tube voltage. The signal produced by the detector without filter is used to evaluate the patient entrance dose, and to active an electronic timer for measuring the real exposure time. The tests and calibration of the instrument in different voltages in the 59 - 70kVp range, showed that its response is both stable and reproducible to within 1%. The instrument response was compared to the one from a commercial non-invasive X-ray test equipment (Gammex RMI Multifunction kVp meter). The results showed that the response of the developed instrument is in good agreement with the RMI meter which is the standard equipment for such measurements. These results indicate that the dosimetric system is suitable for use in Dental Quality Assurance Programs. (author)

  4. Development and application of a dosimetric methodology of therapeutic X radiation beams using a tandem system

    International Nuclear Information System (INIS)

    Sartoris, Carla Eri

    2001-01-01

    In radiotherapy the use of orthovoltage X radiation beams is still recommended; to obtain satisfactory results, a periodic control is necessary to check the performance of the ionization chambers and the radiation beams characteristics. This control is performed by using standard dosimetric procedures, as for example the determination of half-value layers and the absorbed dose rates. A Tandem system was established in this work using a pair of ionization chambers (a thimble type and a superficial type) used for measures in a medical institution, in substitution to the routine conventional procedure of determination of half-value layers using absorbers. The results obtained show the application of this method in dosimetric procedures of orthovoltage beams (radiotherapy) as a complement for a quality control program. (author)

  5. Development of newborn chest phantom for dosimetric study in computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Aburjaile, W.N.; Lima, L.T.A.; Mourao, A.P., E-mail: wadia.namen@gmail.com [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Departamento de Engenharia Nuclear; Centro Federal de Educação Tecnológica de Minas Gerais (CEFET-MG), Belo Horizonte, MG (Brazil). Centro de Engenharia Biomédica

    2017-11-01

    Computed Tomography (CT) is a radiodiagnostic technique that allows evaluating the patient internal structures. In the last ten years, this technique has shown a high growth due to clinical cases of medical emergencies, neoplasm and pediatric traumas. The use dissemination of this technique has a significant increase in the patient dose. CT equipment installed in radiodiagnostic services present technological variations in the speed of acquisition or in the protocols used to obtain sectional images. The dose deposited in pediatric patients is directly related to energy retained during the exposure process to ionizing radiation, and radiation future effects is related with stochastic risks due to tissue radiosensitivity allied to the life expectancy of the child. The risk associated with a radiological examination can be considered quite low compared to the natural risk. However, any additional risk, no matter how small, is unacceptable if it does not benefit the patient. The knowledge of dose distribution is important when considering the variation of the acquisition parameters in order to reduce the dose. The objective of this work is to develop a newborn chest phantom for realize a comparative dosimetric study with the an adult standard phantom in order to evaluate the dose variation in CT scans. In this work, a cylindrical phantom, representing an adult chest made of polymethylmethacrylate (PMMA), was used and a new born chest phantom with a shape oblong was developed based on the dimensions of a typical newborn. In a GE CT scanner, Discovery model, with 64 channels, the central slice of the phantoms were irradiated successively in order to obtain dose measurements using an ionizing pencil camera. The radiological service chest protocol using a voltage of 120 kV was used for scanning 10 cm of the central area of the adult and newborn phantoms, in helical mode. The measurements have allowed to obtain the volumetric dose index values for the adult and newborn

  6. Study of dosimetric parameters for iodine-125 brachytherapy sources development from IPEN-CNEN/SP using Monte Carlo method

    International Nuclear Information System (INIS)

    Oliveira, Tiago Batista de

    2016-01-01

    Expectations of the World Health Organization for the year 2030 are that the number of cancer deaths is approximately 13.2 million, reflecting the high proportion of this disease in global health issue. With respect to prostate cancer, according to the National Cancer Institute, the number of cases diagnosed worldwide in 2012 was approximately 1.1 million, while in Brazil the data demonstrated the incidence of 68,000 new cases. The treatment of cancer can be performed with surgery (prostatectomy) or radiation therapy. Among radiotherapy, we can highlight the brachytherapy technique, which consists in the introduction of small radioactive sources (seeds) within the prostate, which is delivered a high dose value in the treatment volume and low dose in the surrounding tissues. In Brazil, the medical profession estimates a demand of approximately 8000 seeds / month, and the unit cost of each seed at least US $ 26.00. The AAPM protocol TG-43 recommend the dose-rate constant, radial dose function and anisotropy function for dosimetric analysis LDR brachytherapy seeds. In this work, Monte Carlo simulations were performed in order to assess the dosimetric parameters of the OncoSeed-6711, manufactured by Oncura-GEHealthcare, and a seed developed by Radiation Technology Center, using the MCNP5 code. A 6711 seed, an IPEN seed and the 30 x 30 x 30cm 3 phantom filled with water were modeled to simulate the dose distribution. The 6711 seed parameters were compared with literature, and the results presented relative error less than 0.1% for Λ. In comparison with the 6711 seed, the IPEN model seed dosimetric parameters were similar, account the statistical uncertainty. (author)

  7. Development and validation of an ex vivo electron paramagnetic resonance fingernail bio-dosimetric method

    International Nuclear Information System (INIS)

    He, Xiaoming; Swarts, Steven G.; Marsh, Stephen D.; Demidenko, Eugene; Flood, Ann B.; Grinberg, Oleg; Gui, Jiang; Mariani, Michael; Ruuge, Andres E.; Tipikin, Dmitry; Swartz, Harold M.; Sidabras, Jason W.; Wilcox, Dean E.

    2014-01-01

    There is an imperative need to develop methods that can rapidly and accurately determine individual exposure to radiation for screening (triage) populations and guiding medical treatment in an emergency response to a large-scale radiological/nuclear event. To this end, a number of methods that rely on dose-dependent chemical and/or physical alterations in biomaterials or biological responses are in various stages of development. One such method, ex vivo electron paramagnetic resonance (EPR) nail dosimetry using human nail clippings, is a physical bio-dosimetry technique that takes advantage of a stable radiation-induced signal (RIS) in the keratin matrix of fingernails and toenails. This dosimetry method has the advantages of ubiquitous availability of the dosimetric material, easy and non-invasive sampling, and the potential for immediate and rapid dose assessment. The major challenge for ex vivo EPR nail dosimetry is the overlap of mechanically induced signals and the RIS. The difficulties of analysing the mixed EPR spectra of a clipped irradiated nail were addressed in the work described here. The following key factors lead to successful spectral analysis and dose assessment in ex vivo EPR nail dosimetry: (1) obtaining a thorough understanding of the chemical nature, the decay behaviour, and the microwave power dependence of the EPR signals, as well as the influence of variation in temperature, humidity, water content, and O 2 level; (2) control of the variability among individual samples to achieve consistent shape and kinetics of the EPR spectra; (3) use of correlations between the multiple spectral components; and (4) use of optimised modelling and fitting of the EPR spectra to improve the accuracy and precision of the dose estimates derived from the nail spectra. In the work described here, two large clipped nail datasets were used to test the procedures and the spectral fitting model of the results obtained with it. A 15-donor nail set with 90 nail samples

  8. Experience in the performance of a system of dosimetric design of radiotherapy and prospects of its development

    International Nuclear Information System (INIS)

    Tsyb, A.F.; Mardynskij, Yu.S.; Chilingarov, K.M.

    1987-01-01

    A model of a system of dosimetric design of radiotherapy on the basis of SM-4 and ES-1033 computers has been developed and is being tested. Radiotherapy for over 600 patients with tumors of different sites was designed within 1 year. The simplicity of the system allowed a radiologist to take an active part in the choice of a favourable radiotherapy design. Four variants of dose distributions on an average were computed for each patient. A study of the time characteristics of the system has shown that the time of input of the data on a patient and beam parameters does not practically depend on the computer speed and lasts for an average of 15 min. Dose field computation and optimization of inputs vary from 0.4 to 6 min depending on a volume of computation and computer type. A one-task computer system with one working place and memory is able to meet the requirements in dosimetric design for 2-3 radiotherapeutic units. More units will require multitask and all-purpose computers with 2 and more working places. Minimum standards of computer memory and speed are the same as in the first case

  9. Development of a thermally stimulated exoelectron emission (TSEE) system for dosimetric applications

    International Nuclear Information System (INIS)

    Rocha, Felicia del Gallo

    1997-01-01

    A thermally stimulated exoelectron emission measuring system (TSEE) with a counting (reader) and a heating system was designed, constructed and tested for the dosimetry of weakly penetrating radiations, such as alpha and beta particles and low energy X rays. The counting system consists of a 271 windowless gas-flow proportional counter, while the heating system is composed by a temperature programmer that provides linear heating of the samples. The characterization of the proportional counter was done, as well as the tests to verify the performance of the counting system with reference TSEE materials, such as beryllium oxide (BeO) and magnesium oxide (MgO) single crystals. The dosimetric characteristics of some materials as pure calcium sulphate (CaS0 4 ) sintered pellets and with 10% of graphite in its composition, lithium fluoride doped with magnesium, copper and phosphor (LiF:Mg,Cu,P), lithium fluoride (LiF) thin films on aluminum and stainless steel substrates and BeO on graphite substrates were studied. As an application, the feasibility of the use of pure calcium sulphate sintered pellets and others with 10% of graphite in area monitoring of an electron accelerator with variable energy was studied. The obtained results show the usefulness of this system in the dosimetry of weakly penetrating radiations. (author)

  10. Development of an automatic visual grading system for grafting seedlings

    Directory of Open Access Journals (Sweden)

    Subo Tian

    2017-01-01

    Full Text Available In this study, a visual grading system of vegetable grafting machine was developed. The study described key technology of visual grading system of vegetable grafting machine. First, the contrasting experiment was conducted between acquired images under blue background light and natural light conditions, with the blue background light chosen as lighting source. The Visual C++ platform with open-source computer vision library (Open CV was used for the image processing. Subsequently, maximum frequency of total number of 0-valued pixels was predicted and used to extract the measurements of scion and rootstock stem diameters. Finally, the developed integrated visual grading system was experimented with 100 scions and rootstock seedlings. The results showed that success rate of grading reached up to 98%. This shows that selection and grading of scion and rootstock could be fully automated with this developed visual grading system. Hence, this technology would be greatly helpful for improving the grading accuracy and efficiency.

  11. The dosimetric control in radiotherapy

    International Nuclear Information System (INIS)

    Veres, A.

    2009-01-01

    The author first presents the thermoluminescent dosimetry method developed by the Equal-Estro Laboratory to control radiotherapy systems, according to which dosimeters are mailed by the radiotherapy centres to the laboratory, and then analyzed with respect to the level of dose bias. In a second part, he discusses the different techniques used for the dosimetric control of new radiotherapy methods (intensity-modulated radiation therapy, tomo-therapy) for which film dosimetry is applied. He also evokes the development of new phantoms and the development of a method for the dosimetric control of proton beams

  12. Development of an application for the home acquisition of dosimetric data in patients with differentiated thyroid cancer undergoing 131I therapy

    International Nuclear Information System (INIS)

    Contardi, M.; Namías, M.

    2017-01-01

    Objective: To develop an application under the Android mobile operating system, which, together with a miniature solid-state detector, allows obtaining the necessary dosimetric data for estimation of absorbed dose in blood / marrow in patients treated with 131 I. It is expected that from the development of this application can be counted on a greater amount of information on the doses received in blood / marrow by the patients and in this way help to establish better dose-effect correlations. (authors) [es

  13. Talent Development Middle Grades Program. What Works Clearinghouse Intervention Report

    Science.gov (United States)

    What Works Clearinghouse, 2013

    2013-01-01

    The "Talent Development Middle Grades Program" is a comprehensive reform model that transforms the structure and curriculum of large urban middle schools with the aim of improving student achievement and raising teacher and student expectations. Key features of the "Talent Development Middle Grades Program" include small…

  14. Development of a 2D array silicon detector magic plate for the dosimetric verification of IMRT treatment delivery

    International Nuclear Information System (INIS)

    Wong, J.H.D.; Fuduli, Iolanda; Lerch, M.L.F.; Petasecca, Marco; Metcalfe, P.E.

    2011-01-01

    Full text: We have developed an IMRT and VMAT dosimetry system for pre-treatment and during treatment verification. The 'Magic Plate' (MP) diode array was designed and prototyped by the CMRP and ICCe. It is a 2D diode array that can be used for in phantom dose measurement and can also function as a transmission detector for in vivo measurements during patient treatment. The prototype MP comprises of II x 11 silicon diodes mounted on a 0.6 mm Kapton substrate. Detectors are spaced 1 cm apart with sensitive volumes of 0.5 x 0.5 x 0.05 mm'. Phantom measurements were performed using the MP located at isocentre in the cavity of an l'mRT phantom. For fluence measurements in transmission mode the MP was mounted on the linac accessory slot. The detector was characterized and a nine field head and neck IMRT test plan was delivered. Measurements were compared with EBT2 films and Pinnacle predicted dose distributions. The 3%/3 mm gamma criteria was used for comparison. Average pass rates for the MP versus Pinnacle and MP versus EBT2 were 82.9 and 88.1 % in the phantom. Gamma analysis of MP versus EBT2 when used as transmission detectors gave a pass rate of 94.8%. The prototype MP design shows promise as IMRT dosimetric system. Future work involves refining the acquisition system, further detailed characterization, Monte Carlo simulation of the detector and its application to VMAT.

  15. Development of functionally graded materials by ultrasonic consolidation

    CSIR Research Space (South Africa)

    Kumar, S

    2010-08-01

    Full Text Available Development of Functionally Graded Materials (FGM) using Ultrasonic Consolidation (UC) needs the joining of different metallic foils together. The present work deals with the joining of stainless steel, Al and Cufoils. Optimum experimental...

  16. Development and dosimetric characterization of indigenous PADC for personnel neutron dosimetry

    Directory of Open Access Journals (Sweden)

    Pal Rupali

    2015-01-01

    Full Text Available CR-39 is a solid state nuclear track detector, chemically known as poly-allyl-diglycol-carbonate, widely used for personnel neutron monitoring because of its sensitivity to neutrons, excellent optical properties that facilitate the analysis and sufficiently long shelf life. Presently, this detector is imported and is being used for the personnel neutron monitoring programme in India. Hence, an effort was made towards the indigenous development of these detectors. Different chemical processes for the indigenous development of the poly-allyl-diglycol-carbonate detector, such as the synthesis of allyl-diglycol-carbonate monomer and isopropyl-peroxydicarbonate as initiators for the polymerization process, were carried out and are reported in this paper. A method for casting unbroken poly-allyl-diglycol-carbonate sheets sized 25 cm x 15 cm and of a thickness between 500 µm and 800µm was developed. A longer polymerization process also helps to increase neutron sensitivity, reduce the minimum detection limit and increase the signal-to-noise ratio of the detector. The study suggests that it is possible to develop indigenous poly-allyl-diglycol-carbonate detectors with a minimum detection limit of 0.1 mSv and signal-to-noise ratio of 8.0.

  17. Dosimetric investigations in mammography

    International Nuclear Information System (INIS)

    Metges, P.J.; Lorrain, S.

    1981-01-01

    The development film-screen detectors in radiological equipment has led us to study how to improve standard mammographic pictures (focus 0.3 x 0.3 mm, focus-film distance: 65) of thick and dense breasts by the use of an anti-scatter grid and by magnification. A dosimetric study was necessary to assess the doses delivered during mammographic examinations carried out according to various procedures. The results led to modify breast examination procedures and use an anti-scatter grid for breasts thicker than 4 cm or known as dense. The dose increase due to a better quality image is the lowest provided depth penetration is increased by 2 kV as compared to a standard picture. Absorbed doses on the X-ray axis, at 3 cm depth, are below 0.1 rad [fr

  18. MO-FG-BRA-01: Development of An Image-Guided Dosimetric Planning System for Injectable Brachytherapy Using ELP Nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Lafata, K [Duke University, Durham, North Carolina (United States); Duke University Medical Center, Durham, NC (United States); Schaal, J; Liu, W [Duke University, Durham, North Carolina (United States); Cai, J [Duke University Medical Center, Durham, NC (United States)

    2015-06-15

    Purpose: To develop, validate, and evaluate a methodology for determining dosimetry for intratumoral injections of elastin-like-polypeptide (ELP) brachytherapy nanoparticles. These organic-polymer-based nanoparticles are injectable, biodegradable, and genetically tunable. We present a genetically encoded polymer-solution, composed of novel radiolabeled-ELP nanoparticles that are custom-designed to self-assemble into a local source upon intratumoral injection. Our preliminary results of a small animal study demonstrate 100% tumor response, effective radionuclide retention-rates, strong in vivo stability, and no polymer-induced toxicities. While our approach is therefore highly promising for improved brachytherapy, the current workflow lacks a dosimetry framework. Methods: We are developing a robust software framework that provides image-guided dosimetric-planning capabilities for ELP brachytherapy. The user graphically places ELP injection sites within a µCT-planning-image, and independently defines each injection volume, concentration, and radioisotope to be used. The resulting internal dosimetry is then pre-determined by first modeling post-injection ELP advection-diffusion, and then calculating the resulting dose distribution based on a point- dose-kernel-convolution algorithm. We have experimentally measured ELP steady-state concentrations via µSPECT acquisition, and validated our dose calculation algorithm against Monte Carlo simulations of several radioactivity distributions. Finally, we have investigated potential advantages and limitations of various ELP injection parameters. Results: The µSPECT results demonstrated inhomogeneous steady-state distributions of ELP in tissue, and Monte Carlo radioactivity distributions were designed accordingly. Our algorithm yielded a root-mean-square-error of less than 2% for each distribution tested (average root-mean-square-error was 0.73%). Dose-Volume-Histogram analysis of five different plans showed how strategic

  19. Development of a computational system based in the code GEANT4 for dosimetric evaluation in radiotherapy

    International Nuclear Information System (INIS)

    Oliveira, Alex Cristovao Holanda de

    2016-01-01

    The incidence of cancer has grown in Brazil, as well as around the world, following the change in the age profile of the population. One of the most important techniques and commonly used in cancer treatment is radiotherapy. Around 60% of new cases of cancer use radiation in at least one phase of treatment. The most used equipment for radiotherapy is a linear accelerator (Linac) which produces electron or X-ray beams in energy range from 5 to 30 MeV. The most appropriate way to irradiate a patient is determined during treatment planning. Currently, treatment planning system (TPS) is the main and the most important tool in the process of planning for radiotherapy. The main objective of this work is to develop a computational system based on the MC code Geant4 for dose evaluations in photon beam radiotherapy. In addition to treatment planning, these dose evaluations can be performed for research and quality control of equipment and TPSs. The computer system, called Quimera, consists of a graphical user interface (qGUI) and three MC applications (qLinacs, qMATphantoms and qNCTphantoms). The qGUI has the function of interface for the MC applications, by creating or editing the input files, running simulations and analyzing the results. The qLinacs is used for modeling and generation of Linac beams (phase space). The qMATphantoms and qNCTphantoms are used for dose calculations in virtual models of physical phantoms and computed tomography (CT) images, respectively. From manufacturer's data, models of a Varian Linac photon beam and a Varian multileaf collimator (MLC) were simulated in the qLinacs. The Linac and MLC modelling were validated using experimental data. qMATphamtoms and qNCTphantoms were validated using IAEA phase spaces. In this first version, the Quimera can be used for research, radiotherapy planning of simple treatments and quality control in photon beam radiotherapy. The MC applications work independent of the qGUI and the qGUI can be used for

  20. Development of a dosimetric system for the quality control of breast cancer treatments

    International Nuclear Information System (INIS)

    Chaves, Roberio C.; Crispim, Verginia R.; Santos, Delano B.V.

    2013-01-01

    A system for evaluating the values of absorbed dose in breast teletherapy was developed, using thermoluminescent dosimeters (TLD-100), to compare them to those provided by Therapy planning system. A breast phantom was made to distribute the dosimeters TL shaped chip in breast volume and irradiate it under the same conditions of planning. Three different techniques of teletherapy were considered: one with irradiation from a therapy unit of 60 Co and two with an X-ray beam coming from a 6 MV linear accelerator. Doses measures allowed checking that the performance of the quality control system used in breast cancer treatment is appropriate, since the planned doses differed about 1.5% of the responses provided by TL dosimeters

  1. Development of a deformable dosimetric phantom to verify dose accumulation algorithms for adaptive radiotherapy

    Directory of Open Access Journals (Sweden)

    Hualiang Zhong

    2016-01-01

    Full Text Available Adaptive radiotherapy may improve treatment outcomes for lung cancer patients. Because of the lack of an effective tool for quality assurance, this therapeutic modality is not yet accepted in clinic. The purpose of this study is to develop a deformable physical phantom for validation of dose accumulation algorithms in regions with heterogeneous mass. A three-dimensional (3D deformable phantom was developed containing a tissue-equivalent tumor and heterogeneous sponge inserts. Thermoluminescent dosimeters (TLDs were placed at multiple locations in the phantom each time before dose measurement. Doses were measured with the phantom in both the static and deformed cases. The deformation of the phantom was actuated by a motor driven piston. 4D computed tomography images were acquired to calculate 3D doses at each phase using Pinnacle and EGSnrc/DOSXYZnrc. These images were registered using two registration software packages: VelocityAI and Elastix. With the resultant displacement vector fields (DVFs, the calculated 3D doses were accumulated using a mass-and energy congruent mapping method and compared to those measured by the TLDs at four typical locations. In the static case, TLD measurements agreed with all the algorithms by 1.8% at the center of the tumor volume and by 4.0% in the penumbra. In the deformable case, the phantom's deformation was reproduced within 1.1 mm. For the 3D dose calculated by Pinnacle, the total dose accumulated with the Elastix DVF agreed well to the TLD measurements with their differences <2.5% at four measured locations. When the VelocityAI DVF was used, their difference increased up to 11.8%. For the 3D dose calculated by EGSnrc/DOSXYZnrc, the total doses accumulated with the two DVFs were within 5.7% of the TLD measurements which are slightly over the rate of 5% for clinical acceptance. The detector-embedded deformable phantom allows radiation dose to be measured in a dynamic environment, similar to deforming lung

  2. Development of dosimetric approaches to treatment planning for radioimmunotherapy. Annual report 1989--1990

    Energy Technology Data Exchange (ETDEWEB)

    DeNardo, S.J.

    1990-12-31

    The objective of quantitative imaging is to provide pharmacokinetic information for patients that is analogous to that provided by biodistribution studies in mice. Radionuclide images depict the distribution of labeled antibodies in-vivo; thus the amount of radionuclide in a specific organ or site can be estimated by relating the counts detected in a defined region of interest to the total radionuclide content. This pharmacokinetic information can be used to obtain definitive and relevant answers to basic questions of importance for optimizing radioimmunoimaging and radioimmunotherapy and, in addition, can provide a data base from which to calculate the distribution of radiation absorbed doses. The research employs quantitative imaging in evaluating therapies. Quantitative imaging is performed by a certified nuclear medicine technician using the Siemens gamma camera interfaced with the microVAX II. The technician processes the imaging data and obtains pharmacokinetic information from it using programs developed by the authors and others. A large amount of data has been acquired and analyzed on the pharmacokinetics, dosimetry and toxicity of radiolabeled monoclonal therapy. Important dosimetry data on the whole body, marrow and tumor doses are available and all studies are archived so that they can be retrospectively analyzed. Although the radiation absorbed doses delivered to tumor sites were modest, significant biological responses were found.

  3. Development of dosimetric approaches to treatment planning for radioimmunotherapy. DOE annual report

    International Nuclear Information System (INIS)

    1998-01-01

    The objective of quantitative imaging is to Provide pharmacokinetic information for patients that is analogous to that provided by biodistribution studies in mice. Radio nuclide images depict the distribution of labeled antibodies in-vivo; thus the amount of radio nuclide in a specific organ or site can be estimated by relating the counts detected in a defined region of interest to the total radio nuclide content. This pharmacokinetic information can be used to obtain definitive and relevant answers to basic questions of importance for optimizing radioimmunoimaging and radioimmunotherapy and, in addition, can provide a data base from which to calculate the distribution of radiation absorbed doses. The projects supported by this program routinely employ quantitative imaging in evaluating therapies. Quantitative imaging is performed by a certified nuclear medicine technician using the Siemens gamma camera interfaced with the microVAX II. The technician processes the imaging data and obtains pharmacokinetic information from it using programs developed by us and others. During this grant period project staff have acquired and analyzed a large amount of data on the pharmacokinetics, dosimetry and toxicity of radiolabeled monoclonal therapy. Important dosimetry data on the whole body, marrow and tumor doses are available and all studies are archived so that they can be retrospectively analyzed

  4. Development of dosimetric approaches to treatment planning for radioimmunotherapy. DOE annual report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-05-01

    The objective of quantitative imaging is to Provide pharmacokinetic information for patients that is analogous to that provided by biodistribution studies in mice. Radio nuclide images depict the distribution of labeled antibodies in-vivo; thus the amount of radio nuclide in a specific organ or site can be estimated by relating the counts detected in a defined region of interest to the total radio nuclide content. This pharmacokinetic information can be used to obtain definitive and relevant answers to basic questions of importance for optimizing radioimmunoimaging and radioimmunotherapy and, in addition, can provide a data base from which to calculate the distribution of radiation absorbed doses. The projects supported by this program routinely employ quantitative imaging in evaluating therapies. Quantitative imaging is performed by a certified nuclear medicine technician using the Siemens gamma camera interfaced with the microVAX II. The technician processes the imaging data and obtains pharmacokinetic information from it using programs developed by us and others. During this grant period project staff have acquired and analyzed a large amount of data on the pharmacokinetics, dosimetry and toxicity of radiolabeled monoclonal therapy. Important dosimetry data on the whole body, marrow and tumor doses are available and all studies are archived so that they can be retrospectively analyzed.

  5. Development of a three-dimensionally movable phantom system for dosimetric verifications

    International Nuclear Information System (INIS)

    Nakayama, Hiroshi; Mizowaki, Takashi; Narita, Yuichiro; Kawada, Noriyuki; Takahashi, Kunio; Mihara, Kazumasa; Hiraoka, Masahiro

    2008-01-01

    The authors developed a three-dimensionally movable phantom system (3D movable phantom system) which can reproduce three-dimensional movements to experimentally verify the impact of radiotherapy treatment-related movements on dose distribution. The phantom system consists of three integrated components: a three-dimensional driving mechanism (3D driving mechanism), computer control system, and phantoms for film dosimetry. The 3D driving mechanism is a quintessential part of this system. It is composed of three linear-motion tables (single-axis robots) which are joined orthogonally to each other. This mechanism has a motion range of 100 mm, with a maximum velocity of 200 mm/s in each dimension, and 3D motion ability of arbitrary patterns. These attributes are sufficient to reproduce almost all organ movements. The positional accuracy of this 3D movable phantom system in a state of geostationary is less than 0.1 mm. The maximum error in terms of the absolute position on movement was 0.56 mm. The positional reappearance error on movement was up to 0.23 mm. The observed fluctuation of time was 0.012 s in the cycle of 4.5 s of oscillation. These results suggested that the 3D movable phantom system exhibited a sufficient level of accuracy in terms of geometry and timing to reproduce interfractional organ movement or setup errors in order to assess the influence of these errors on high-precision radiotherapy such as stereotactic irradiation and intensity-modulated radiotherapy. In addition, the authors 3D movable phantom system will also be useful in evaluating the adequacy and efficacy of new treatment techniques such as gating or tracking radiotherapy

  6. A Dosimetric Study on Slab-pinewood-slab Phantom for Developing the Heterogeneous Chest Phantom Mimicking Actual Human Chest.

    Science.gov (United States)

    Gurjar, Om Prakash; Paliwal, Radha Kishan; Mishra, Surendra Prasad

    2017-01-01

    The aim is to study the density, isodose depths, and doses at different points in slab-pinewood-slab (SPS) phantom, solid phantom SP34 (made up of polystyrene), and chest level of actual patient for developing heterogeneous chest phantom mimicking thoracic region of human body. A 6 MV photon beam of field size of 10 cm × 10 cm was directed perpendicular to the surface of computed tomography (CT) images of chest level of patient, SPS phantom, and SP34 phantom. Dose was calculated using anisotropic analytical algorithm. Hounsfield units were used to calculate the density of each medium. Isodose depths in all the three sets of CT images were measured. Variations between planned doses on treatment planning system (TPS) and measured on linear accelerator (LA) were calculated for three points, namely, near slab-pinewood interfaces (6 and 18 cm depths) and 10 cm depth in SPS phantom and at the same depths in SP34 phantom. Density of pinewood, SP34 slabs, chest wall, lung, and soft tissue behind lung was measured as 0.329 ± 0.08, 0.999 ± 0.02, 0.898 ± 0.02, 0.291 ± 0.12, and 1.002 ± 0.03 g/cc, respectively. Depths of 100% and 90% isodose curves in all the three sets of CT images were found to be similar. Depths of 80%, 70%, 60%, 50%, and 40% isodose lines in SPS phantom images were found to be equivalent to that in chest images, while it was least in SP34 phantom images. Variations in doses calculated at 6, 10, and 18 cm depths on TPS and measured on LA were found to be 0.36%, 1.65%, and 2.23%, respectively, in case of SPS phantom, while 0.24%, 0.90%, and 0.93%, respectively, in case of SP34 slab phantom. SPS phantom seemed equivalent to the chest level of human body. Dosimetric results of this study indicate that patient-specific quality assurance can be done using chest phantom mimicking thoracic region of human body, which has been fabricated using polystyrene and pinewood.

  7. Dosimetric characterization of the Exradin W1 plastic scintillator detector through comparison with an in-house developed scintillator system

    DEFF Research Database (Denmark)

    Beierholm, Anders Ravnsborg; Behrens, Claus F.; Andersen, Claus E.

    2014-01-01

    method, but differing primarily in the signal detection hardware. The two systems were compared with respect to essential dosimetric properties, with the purpose of testing their performance under conditions less well discussed in the literature. A Farmer ionization chamber was used as the primary...... is therefore advised if using either system for measurements in large fields or under circumstances where the fibre irradiation geometry is unfavourable. Measurements of reference dose to water yielded differences up to 1.5% when compared with the Farmer ionization chamber for all investigated beam qualities...

  8. Developing evidence-based immunization recommendations and GRADE.

    Science.gov (United States)

    Duclos, P; Durrheim, D N; Reingold, A L; Bhutta, Z A; Vannice, K; Rees, H

    2012-12-17

    The Strategic Group of Advisory Experts (SAGE) on immunization is an independent advisory committee with a mandate to advise the World Health Organization (WHO) on the development of vaccine and immunization related policies. SAGE working groups are established on a time-limited basis to review and provide evidence-based recommendations, together with their implications, for open deliberation and decision-making by SAGE. In making its recommendations, SAGE takes into consideration: the epidemiologic and clinical characteristics of the disease; vaccine and immunization characteristics; economic analysis; health system considerations; the existence of and interaction with other intervention and control strategies; costing and social impacts; and legal and ethical concerns. Since 1998, WHO has produced evidence-based vaccine position papers for use primarily by national public health officials and immunization programme managers. Since April 2006 all new or updated position papers have been based on SAGE recommendations. The Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach has been adopted by WHO and, since 2008, GRADE tables that rate the quality of evidence have been produced in support of key recommendations. SAGE previously expressed concern that GRADE was not ideally suited to many immunization-specific issues such as the vaccine population level effect and the inclusion of surveillance system data, particularly for vaccine safety. Extensive productive interactions with various advisory groups including the US Advisory Committee on Immunization Practices, the European Centres for Disease Control, the German Standing Committee on Vaccination (STIKO), WHO's Global Advisory Committee on Vaccine Safety and the GRADE working group resulted in key enhancements to accommodate vaccine-relevant evidence. This facilitated integration and acceptability of the GRADE approach in the development of immunization related SAGE and WHO

  9. Environmental Education Curriculum Development, Grade 6, For St. Martin Parish.

    Science.gov (United States)

    Saint Martin Parish School Board, St. Martinville, LA.

    This environmental education curriculum guide is designed for teacher use in the sixth grade. It contains seven units that aim to help the students acquire basic understanding of environmental relationships, environmental problems, environmental quality and to help the students develop skills to solve current environmental problems. Each unit,…

  10. Major Hindrance to the Development of Autonomy among Grade ...

    African Journals Online (AJOL)

    In order to find out the major hindrances to the development of autonomy among Grade Nine students at Baso General Secondary School in learning English, necessary data were collected from one hundred-fifty students, three English teachers and ten students through questionnaire, semi-structured interview and focus ...

  11. Linguistic Feature Development Across Grades and Genre in Elementary Writing.

    Science.gov (United States)

    Hall-Mills, Shannon; Apel, Kenn

    2015-07-01

    As children develop skills in writing across academic contexts, clinicians and educators need to have a fundamental understanding of typical writing development as well as valid and reliable assessment methods. The purpose of this study was to examine the progression of linguistic elements in school-age children's narrative and expository writing development. Narrative and expository writing samples produced by 89 children in Grades 2 through 4 were analyzed at the microstructure and macrostructure levels. Measures of receptive vocabulary, word-level reading, and reading comprehension were obtained. Exploratory factor analyses revealed 4 microstructure factors (e.g., productivity, grammatical complexity, grammatical accuracy, and lexical density) and 1 macrostructure factor (e.g., a combination of organization, text structure, and cohesion). Multivariate analyses of covariance with reading comprehension as a covariate showed that productivity and macrostructure were sensitive to grade-level and genre differences and that expository grammatical complexity was sensitive to grade-level differences. Findings are discussed in light of grade-level standards for narrative and expository writing and current practices in writing assessment. Multiple suggestions are offered for clinical and educational implications, and specific directions are provided for future research.

  12. Development of nuclear grade stainless steels at KCSSL

    International Nuclear Information System (INIS)

    Balachandran, G.; Dhere, M.; Mahadik, A.; Hinge, N.M.; Balasubramanian, V.

    2011-01-01

    Kalyani Carpenter Special Steels Ltd is an alloy steel plant, where a variety of alloy steel grades are produced for automotive, defence, nuclear and aerospace applications. The plant has developed expertise in processing of several alloy steel grades of superior quality that meets stringent specifications. Primary steel is processed through a combination of electric arc furnace, ladle furnace and vacuum degassing where stringent control over dephosphorisation, desulphurization, deoxidation is effected to get a refined high quality steel. The molten steel is cast through continuous casting of slabs or ingot casting. In grades specific to nuclear application, the primary cast products are further subjected to electroslag remelting to achieve further freedom from inclusions and to achieve a favourable solidification grain structure, which ultimately improve the hot workability of the alloy steel. Appropriate choice of slag and operating parameters are needed for realising the required ingot quality. The present study would examine the processing and quality aspects of some important grades of steels used in nuclear industry namely ferritic 9Cr-1Mo steel, martensitic stainless steels 403, 410, precipitation hardenable 17-4 PH stainless steel and austenitic 321, 316LN stainless steel, which were made and supplied for applications to Indian nuclear industry. The expertise developed in processing the steels in terms of melting, heat treatment and their relationship to structural features and mechanical properties would be highlighted. (author)

  13. Software development for statistical handling of dosimetric and epidemiological data base; Programacion para la explotacion estadistica de los bancos de datos dosimetrico y epidemiologico

    Energy Technology Data Exchange (ETDEWEB)

    Amaro, M.

    1990-07-01

    The dose records from different groups of occupationally exposed workers are available in a computerized data base whose main purpose is the individual dose follow-up. Apart from this objective, such a dosimetric data base can be useful to obtain statistical analysis. The type of statistical n formation that can be extracted from the data base may aim to attain mainly two kinds of objectives: - Individual and collective dose distributions and statistics. -Epidemiological statistics. The report describes the software developed to obtain the statistical reports required by the Regulatory Body, as well as any other type of dose distributions or statistics to be included in epidemiological studies A Users Guide for the operators who handle this software package, and the codes listings, are also included in the report. (Author) 2 refs.

  14. Development of a dosimetric system for emergency situation involving person of the public; Desenvolvimento de um sistema dosimetrico para situacoes de emergencia envolvendo pessoas do publico em geral

    Energy Technology Data Exchange (ETDEWEB)

    Costa, Zelia Maria da

    1999-07-01

    A dosimetric system was developed for emergency situation based on electron spin resonance spectrometry (E.S.R.) and some materials such as tooth enamel, bovine bone, CaCO{sub 3} and sugar as detector. The purpose of this work was to find common materials, which are both reliable and sensitive and make possible quickly to assess the absorbed dose. The research includes the collection and preparation of samples, the evaluation, treatment and interpretation of ESR signal and the procedure for dose reconstruction. The calibration of the dosemeter was performed using gamma radiation from a Co-60 source. The results obtained confirm the variability of the use of this system in case of an accident. (author)

  15. Dosimetric methodology of the ICRP

    International Nuclear Information System (INIS)

    Eckerman, K.F.

    1994-01-01

    Establishment of guidance for the protection of workers and members of the public from radiation exposures necessitates estimation of the radiation dose to tissues of the body at risk. The dosimetric methodology formulated by the International Commission on Radiological Protection (ICRP) is intended to be responsive to this need. While developed for radiation protection, elements of the methodology are often applied in addressing other radiation issues; e.g., risk assessment. This chapter provides an overview of the methodology, discusses its recent extension to age-dependent considerations, and illustrates specific aspects of the methodology through a number of numerical examples

  16. Development of Digital MMIS for Research Reactors: Graded Approaches

    Energy Technology Data Exchange (ETDEWEB)

    Khalil ur, Rahman; Shin, Jin Soo; Heo, Gyun Young [Kyunghee University, Yongin (Korea, Republic of); Son, Han Seong [Joongbu University, Geumsan (Korea, Republic of); Kim, Young Ki; Park, Jae Kwan; Seo, Sang Mun; Kim, Yong Jun [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2012-05-15

    Though research reactors are small in size yet they are important in terms of industrial applications and R and D, educational purposes. Keeping the eye on its importance, Korean government has intention to upgrade and extend this industry. Presently, Korea is operating only HANARO at Korea Atomic Energy Research Institute (KAERI) and AGN-201K at Kyung Hee University (KHU), which are not sufficient to meet the current requirements of research and education. In addition, we need self-sufficiency in design and selfreliance in design and operation, as we are installing research reactors in domestic as well as foreign territories for instance Jordan. Based on these demands, KAERI and universities initiated a 5 year research project since December 2011 collaboratly, for the deep study of reactor core, thermal hydraulics, materials and instrumentation and control (I and C). This particular study is being carried out to develop highly reliable advanced digital I and C systems using a grading approach. It is worth mentioning that next generation research reactor should be equipped with advance state of the art digital I and C for safe and reliable operation and impermeable cyber security system that is needed to be devised. Moreover, human error is one of important area which should be linked with I and C in terms of Man Machine Interface System (MMIS) and development of I and C should cover human factor engineering. Presently, the digital I and C and MMIS are well developed for commercial power stations whereas such level of development does not exist for research reactors in Korea. Since the functional and safety requirements of research reactors are not so strict as commercial power plants, the design of digital I and C systems for research reactors seems to be graded based on the stringency of regulatory requirements. This paper was motivated for the introduction of those missions, so it is going to describe the general overview of digital I and C systems, the graded

  17. Development of Digital MMIS for Research Reactors: Graded Approaches

    International Nuclear Information System (INIS)

    Khalil ur, Rahman; Shin, Jin Soo; Heo, Gyun Young; Son, Han Seong; Kim, Young Ki; Park, Jae Kwan; Seo, Sang Mun; Kim, Yong Jun

    2012-01-01

    Though research reactors are small in size yet they are important in terms of industrial applications and R and D, educational purposes. Keeping the eye on its importance, Korean government has intention to upgrade and extend this industry. Presently, Korea is operating only HANARO at Korea Atomic Energy Research Institute (KAERI) and AGN-201K at Kyung Hee University (KHU), which are not sufficient to meet the current requirements of research and education. In addition, we need self-sufficiency in design and selfreliance in design and operation, as we are installing research reactors in domestic as well as foreign territories for instance Jordan. Based on these demands, KAERI and universities initiated a 5 year research project since December 2011 collaboratly, for the deep study of reactor core, thermal hydraulics, materials and instrumentation and control (I and C). This particular study is being carried out to develop highly reliable advanced digital I and C systems using a grading approach. It is worth mentioning that next generation research reactor should be equipped with advance state of the art digital I and C for safe and reliable operation and impermeable cyber security system that is needed to be devised. Moreover, human error is one of important area which should be linked with I and C in terms of Man Machine Interface System (MMIS) and development of I and C should cover human factor engineering. Presently, the digital I and C and MMIS are well developed for commercial power stations whereas such level of development does not exist for research reactors in Korea. Since the functional and safety requirements of research reactors are not so strict as commercial power plants, the design of digital I and C systems for research reactors seems to be graded based on the stringency of regulatory requirements. This paper was motivated for the introduction of those missions, so it is going to describe the general overview of digital I and C systems, the graded

  18. Correlation of dosimetric parameters obtained with the analytical anisotropic algorithm and toxicity of chest chemoradiation in lung carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Cartier, Lysian; Auberdiac, Pierre; Khodri, Mustapha; Malkoun, Nadia [Departement de Radiotherapie, Institut de Cancerologie de la Loire, St-Priest en Jarez (France); Chargari, Cyrus [Service d' Oncologie Radiotherapie, Hopital d' Instruction des Armees du Val-de-Grace, Paris (France); Thorin, Julie [Departement de Sante Publique, Unite de Statistique, Institut de Cancerologie de la Loire, St-Priest en Jarez (France); Melis, Adrien [Departement d' Oncologie Medicale, Institut de Cancerologie de la Loire, St-Priest en Jarez (France); Talabard, Jean-Noeel; Laroche, Guy de [Departement de Radiotherapie, Institut de Cancerologie de la Loire, St-Priest en Jarez (France); Fournel, Pierre [Departement d' Oncologie Medicale, Institut de Cancerologie de la Loire, St-Priest en Jarez (France); Tiffet, Olivier [Service de Chirurgie Thoracique, Centre Hospitalier Universitaire de Saint Etienne, Saint Etienne (France); Schmitt, Thierry [Departement de Radiotherapie, Institut de Cancerologie de la Loire, St-Priest en Jarez (France); and others

    2012-07-01

    The purpose of this study was to analyze and revisit toxicity related to chest chemoradiotherapy and to correlate these side effects with dosimetric parameters obtained using analytical anisotropic algorithm (AAA) in locally unresectable advanced lung cancer. We retrospectively analyzed data from 47 lung cancer patients between 2005 and 2008. All received conformal 3D radiotherapy using high-energy linear accelerator plus concomitant chemotherapy. All treatment planning data were transferred into Eclipse 8.05 (Varian Medical Systems, Palo Alto, CA) and dosimetric calculations were performed using AAA. Thirty-three patients (70.2%) developed acute pneumopathy after radiotherapy (grades 1 and 2). One patient (2.1%) presented with grade 3 pneumopathy. Thirty-one (66%) presented with grades 1-2 lung fibrosis, and 1 patient presented with grade 3 lung fibrosis. Thirty-four patients (72.3%) developed grade 1-2 acute oesophagic toxicity. Four patients (8.5%) presented with grades 3 and 4 dysphagia, necessitating prolonged parenteral nutrition. Median prescribed dose was 64 Gy (range 50-74) with conventional fractionation (2 Gy per fraction). Dose-volume constraints were respected with a median V20 of 23.5% (maximum 34%) and a median V30 of 17% (maximum 25%). The median dose delivered to healthy contralateral lung was 13.1 Gy (maximum 18.1 Gy). At univariate analysis, larger planning target volume and V20 were significantly associated with the probability of grade {>=}2 radiation-induced pneumopathy (p = 0.022 and p = 0.017, respectively). No relation between oesophagic toxicity and clinical/dosimetric parameters could be established. Using AAA, the present results confirm the predictive value of the V20 for lung toxicity as already demonstrated with the conventional pencil beam convolution approach.

  19. Application of the GRADE Approach in the Development of Guidelines and Recommendations in Genomic Medicine

    Science.gov (United States)

    Rafiq, Muhammad; Boccia, Stefania

    2018-01-01

    A great deal of ambiguity exists in the development of guidelines for genomic applications used in clinical practice. The GRADE (Grading of Recommendations Assessment, Development and Evaluation) approach has the potential to be applied in the guidelines and recommendations development process in genomics. Here, we discuss whether and how GRADE can be applied to address the challenges posed by the evidence-based guidelines and recommendations development process in genomics. To see how GRADE can complement to the current guidelines development in genomics, we compare and contrast GRADE with other approaches. GRADE differed from other methods by incorporating patient values and preferences and balance of consequences. We conclude that the groups trying to implement genomics into practice may gleam more information from applying the GRADE framework. However, it is not clear yet whether GRADE can address the issue of timeliness in terms of the differences between the time required for guidelines development and the rapid pace of genomics. PMID:29410601

  20. Development of low grade waste heat thermoelectric power generator

    Directory of Open Access Journals (Sweden)

    Suvit Punnachaiya

    2010-07-01

    Full Text Available This research aimed to develop a 50 watt thermoelectric power generator using low grade waste heat as a heat source,in order to recover and utilize the excess heat in cooling systems of industrial processes and high activity radioisotope sources. Electricity generation was based on the reverse operation of a thermoelectric cooling (TEC device. The TEC devices weremodified and assembled into a set of thermal cell modules operating at a temperature less than 100°C. The developed powergenerator consisted of 4 modules, each generating 15 watts. Two cascade modules were connected in parallel. Each modulecomprised of 96 TEC devices, which were connected in series. The hot side of each module was mounted on an aluminumheat transfer pipe with dimensions 12.212.250 cm. Heat sinks were installed on the cold side with cooling fans to provideforced air cooling.To test electricity generation in the experiment, water steam was used as a heat source instead of low grade waste heat.The open-circuit direct current (DC of 250 V and the short-circuit current of 1.2 A was achieved with the following operatingconditions: a hot side temperature of 96°C and a temperature difference between the hot and cold sides of 25°C. The DC poweroutput was inverted to an AC power source of 220 V with 50 Hz frequency, which can continuously supply more than 50 wattsof power to a resistive load as long as the heat source was applied to the system. The system achieved an electrical conversionefficiency of about 0.47 percent with the capital cost of 70 US$/W.

  1. Establishment of a dosimetric system for high doses using glasses

    International Nuclear Information System (INIS)

    Correa Quezada, Valeria de la Asuncion

    1997-01-01

    A routine dosimetric system was developed using commercial glass samples. The dosimetric characteristics of national and imported samples were studied: batch uniformity, response repeatability, reutilization, absorbed dose response, detection range, response stability as a function of absorbed dose, storage temperature and thermal treatments pre- and post-irradiation, using the optical absorption technique. As an application, the dosimetric system was tested in a flower irradiation process at IPEN. All the obtained results show the usefulness of the proposed system for high dose dosimetry. (author)

  2. Researches, development and characterization of dosimetric materials for monitoring in irradiation processes with high doses; Pesquisa, desenvolvimento e caracterizacao de materiais dosimetricos para monitoramento em processos de irradiacao com doses altas

    Energy Technology Data Exchange (ETDEWEB)

    Galante, Ana Maria Sisti

    2003-07-01

    Dosimetric materials that can be produced in Brazil with material acquired in the national market to replace the imported dosimeters used in radiation processing were developed in this work. Mixtures of potassium nitrate and sensitizers compounds as manganese dioxide, barium nitrate and potassium bromide were prepared in the pellet form. Dosimetric characteristics such as dose-response useful range, sensitivity, environmental conditions and dose rate influences were evaluated in {sup 60}Co gamma radiation fields. Dyed polymethylmethacrylate detectors were also produced and its dosimetric characteristics were evaluated. The main characteristics evaluated in this case were: dose response useful range sensitivity, environmental conditions, dose rate influences and radiation energy dependence in gamma radiation fields and accelerated electrons beam of 0.8 to 1.5 MeV. The applied analytic technique was spectrophotometry. The calibration was performed in the irradiation facilities belonging to IPEN and certified by the International Atomic Energy Agency by means of the program IDAS (International Dose Assurance Service ) using the Fricke dosimeter. The mixture of potassium nitrate and manganese dioxide presented the best results and a wide dose range between 200 and 600 kGy. The response of the developed polymethylmethacrylate detectors are similar to the imported detectors and the dose range is characteristic to each detector and depends on the dye added in its formulation. (author)

  3. Development of infant baboons' responses to graded bark variants.

    Science.gov (United States)

    Fischer, J; Cheney, D L; Seyfarth, R M

    2000-11-22

    We studied the development of infant baboons' (Papio cynocephalus ursinus) responses to conspecific 'barks' in a free-ranging population in the Okavango Delta, Botswana. These barks grade from tonal, harmonically rich calls into calls with a more noisy, harsh structure. Typically, tonal variants are given when the signaller is at risk of losing contact with the group or a particular individual ('contact barks'), whereas harsh variants are given in response to predators ('alarm barks'). We conducted focal observations and playback experiments in which we presented variants of barks recorded from resident adult females. By six months of age, infants reliably discriminated between typical alarm and contact barks and they responded more strongly to intermediate alarm calls than to typical contact barks. Infants of six months and older also recognized their mothers by voice. The ability to discriminate between different call variants developed with increasing age. At two and a half months of age, infants failed to respond at all, whereas at four months they responded irrespective of the call type that was presented. At six months, infants showed adult-like responses by responding strongly to alarm barks but ignoring contact barks. We concluded that infants gradually learn to attach the appropriate meaning to alarm and contact barks.

  4. Development, Characterization, and Utilization of Food-Grade Polymer Oleogels.

    Science.gov (United States)

    Davidovich-Pinhas, M; Barbut, Shai; Marangoni, A G

    2016-01-01

    The potential of organogels (oleogels) for oil structuring has been identified and investigated extensively using different gelator-oil systems in recent years. This review provides a comprehensive summary of all oil-structuring systems found in the literature, with an emphasis on ethyl-cellulose (EC), the only direct food-grade polymer oleogelator. EC is a semicrystalline material that undergoes a thermoreversible sol-gel transition in the presence of liquid oil. This unique behavior is based on the polymer's ability to associate through physical bonds. These interactions are strongly affected by external fields such as shear and temperature, as well as by solvent chemistry, which in turn strongly affect final gel properties. Recently, EC-based oleogels have been used as a replacement for fats in foods, as heat-resistance agents in chocolate, as oil-binding agents in bakery products, and as the basis for cosmetic pastes. Understanding the characteristics of the EC oleogel is essential for the development of new applications.

  5. Development of Revised Grade Crossing Hazard Index Model

    Science.gov (United States)

    2017-07-01

    The Nevada Department of Transportation (NDOT) plays a key role in addressing highway-rail grade crossing safety issues by allocating federal funding through the Railway-Highway Crossing (Section 1030) Program. This Program requires each state to sel...

  6. Functionally graded biomimetic energy absorption concept development for transportation systems.

    Science.gov (United States)

    2014-02-01

    Mechanics of a functionally graded cylinder subject to static or dynamic axial loading is considered, including a potential application as energy absorber. The mass density and stiffness are power functions of the radial coordinate as may be the case...

  7. Dosimetric predictors of diarrhea during radiotherapy for prostate cancer

    International Nuclear Information System (INIS)

    Sanguineti, Giuseppe; Endres, Eugene J.; Parker, Brent C.; Sormani, Maria Pia

    2009-01-01

    Purpose: to investigate dosimetric predictors of diarrhea during radiotherapy (RT) for prostate cancer. Patients and methods: all patients who underwent external-beam radiotherapy as part of treatment for localized prostate cancer at the University of Texas Medical Branch, Galveston, TX, USA, from May 2002 to November 2006 were extracted from the own database. From the cumulative dose-volume histogram (DVH), the absolute volumes (V-value) of intestinal cavity (IC) receiving 15, 30, and 45 Gy were extracted for each patient. Acute gastrointestinal toxicity was prospectively scored at each weekly treatment visit according to CTC (common toxicity criteria) v2.0. The endpoint was the development of peak grade ≥ 2 diarrhea during RT. Various patient, tumor, and treatment characteristics were evaluated using logistic regression. Results: 149 patients were included in the analysis, 112 (75.2%) treated with whole-pelvis intensity-modulated radiotherapy (WP-IMRT) and 37 (24.8%) with prostate-only RT, including or not including, the seminal vesicles (PORT ± SV). 45 patients (30.2%) developed peak grade ≥ 2 diarrhea during treatment. At univariate analysis, IC-V 15 and IC-V 30 , but not IC-V 45 , were correlated to the endpoint; at multivariate analysis, only IC-V 15 (p = 0.047) along with peak acute proctitis (p = 0.041) was independently correlated with the endpoint. Conclusion: these data provide a novel and prostate treatment-specific ''upper limit'' DVH for IC. (orig.)

  8. Dosimetric coverage of the prostate, normal tissue sparing, and acute toxicity with high-dose-rate brachytherapy for large prostate volumes

    Energy Technology Data Exchange (ETDEWEB)

    Yang, George; Strom, Tobin J.; Shrinath, Kushagra; Mellon, Eric A.; Fernandez, Daniel C.; Biagioli, Matthew C. [Department of Radiation Oncology, H. Lee Moffitt Cancer Center and Research Institute, Tampa, FL (United States); Wilder, Richard B., E-mail: mcbiagioli@yahoo.com [Cancer Treatment Centers of America, Newnan, GA (United States)

    2015-05-15

    Purpose: to evaluate dosimetric coverage of the prostate, normal tissue sparing, and acute toxicity with HDR brachytherapy for large prostate volumes. Materials and methods: one hundred and two prostate cancer patients with prostate volumes >50 mL (range: 5-29 mL) were treated with high-dose-rate (HDR) brachytherapy ± intensity modulated radiation therapy (IMRT) to 4,500 cGy in 25 daily fractions between 2009 and 2013. HDR brachytherapy monotherapy doses consisted of two 1,350-1,400 cGy fractions separated by 2-3 weeks, and HDR brachytherapy boost doses consisted of two 950-1,150 cGy fractions separated by 4 weeks. Twelve of 32 (38%) unfavorable intermediate risk, high risk, and very high risk patients received androgen deprivation therapy. Acute toxicity was graded according to the Common Terminology Criteria for Adverse Events (CTCAE) version 4. Results: median follow-up was 14 months. Dosimetric goals were achieved in over 90% of cases. Three of 102 (3%) patients developed Grade 2 acute proctitis. No variables were significantly associated with Grade 2 acute proctitis. Seventeen of 102 (17%) patients developed Grade 2 acute urinary retention. American Urological Association (AUA) symptom score was the only variable significantly associated with Grade 2 acute urinary retention (p-0.04). There was no ≥ Grade 3 acute toxicity. Conclusions: dosimetric coverage of the prostate and normal tissue sparing were adequate in patients with prostate volumes >50 mL. Higher pre-treatment AUA symptom scores increased the relative risk of Grade 2 acute urinary retention. However, the overall incidence of acute toxicity was acceptable in patients with large prostate volumes. (author)

  9. Dosimetric Coverage of the Prostate, Normal Tissue Sparing, and Acute Toxicity with High-Dose-Rate Brachytherapy for Large Prostate Volumes

    Directory of Open Access Journals (Sweden)

    George Yang

    2015-06-01

    Full Text Available ABSTRACTPurposeTo evaluate dosimetric coverage of the prostate, normal tissue sparing, and acute toxicity with HDR brachytherapy for large prostate volumes.Materials and MethodsOne hundred and two prostate cancer patients with prostate volumes >50 mL (range: 5-29 mL were treated with high-dose-rate (HDR brachytherapy ± intensity modulated radiation therapy (IMRT to 4,500 cGy in 25 daily fractions between 2009 and 2013. HDR brachytherapy monotherapy doses consisted of two 1,350-1,400 cGy fractions separated by 2-3 weeks, and HDR brachytherapy boost doses consisted of two 950-1,150 cGy fractions separated by 4 weeks. Twelve of 32 (38% unfavorable intermediate risk, high risk, and very high risk patients received androgen deprivation therapy. Acute toxicity was graded according to the Common Terminology Criteria for Adverse Events (CTCAE version 4.ResultsMedian follow-up was 14 months. Dosimetric goals were achieved in over 90% of cases. Three of 102 (3% patients developed Grade 2 acute proctitis. No variables were significantly associated with Grade 2 acute proctitis. Seventeen of 102 (17% patients developed Grade 2 acute urinary retention. American Urological Association (AUA symptom score was the only variable significantly associated with Grade 2 acute urinary retention (p=0.04. There was no ≥ Grade 3 acute toxicity.ConclusionsDosimetric coverage of the prostate and normal tissue sparing were adequate in patients with prostate volumes >50 mL. Higher pre-treatment AUA symptom scores increased the relative risk of Grade 2 acute urinary retention. However, the overall incidence of acute toxicity was acceptable in patients with large prostate volumes.

  10. The Virtual Family-development of surface-based anatomical models of two adults and two children for dosimetric simulations

    Energy Technology Data Exchange (ETDEWEB)

    Christ, Andreas; Honegger, Katharina; Zefferer, Marcel; Neufeld, Esra; Oberle, Michael; Szczerba, Dominik; Kuster, Niels [Foundation for Research on Information Technologies in Society (IT' IS), Zeughausstr. 43, 8004 Zuerich (Switzerland); Kainz, Wolfgang; Guag, Joshua W [US Food and Drug Administration (FDA), Center for Devices and Radiological Health (CDRH), Silver Spring, MD 20993 (United States); Hahn, Eckhart G; Rascher, Wolfgang; Janka, Rolf; Bautz, Werner [Universitaetsklinikum Erlangen, Friedrich-Alexander Universitaet Erlangen-Nuernberg, 91054 Erlangen (Germany); Chen, Ji; Shen, Jianxiang [Department of Electrical and Computer Engineering, The University of Houston, Houston, TX 77204 (United States); Kiefer, Berthold; Schmitt, Peter; Hollenbach, Hans-Peter [Siemens Healthcare, MR-Application Development, 91052 Erlangen (Germany); Kam, Anthony [Department of Imaging, Johns Hopkins Bayview Medical Center, Baltimore, MD 21224 (United States)], E-mail: christ@itis.ethz.ch

    2010-01-21

    The objective of this study was to develop anatomically correct whole body human models of an adult male (34 years old), an adult female (26 years old) and two children (an 11-year-old girl and a six-year-old boy) for the optimized evaluation of electromagnetic exposure. These four models are referred to as the Virtual Family. They are based on high resolution magnetic resonance (MR) images of healthy volunteers. More than 80 different tissue types were distinguished during the segmentation. To improve the accuracy and the effectiveness of the segmentation, a novel semi-automated tool was used to analyze and segment the data. All tissues and organs were reconstructed as three-dimensional (3D) unstructured triangulated surface objects, yielding high precision images of individual features of the body. This greatly enhances the meshing flexibility and the accuracy with respect to thin tissue layers and small organs in comparison with the traditional voxel-based representation of anatomical models. Conformal computational techniques were also applied. The techniques and tools developed in this study can be used to more effectively develop future models and further improve the accuracy of the models for various applications. For research purposes, the four models are provided for free to the scientific community. (note)

  11. The Virtual Family-development of surface-based anatomical models of two adults and two children for dosimetric simulations

    International Nuclear Information System (INIS)

    Christ, Andreas; Honegger, Katharina; Zefferer, Marcel; Neufeld, Esra; Oberle, Michael; Szczerba, Dominik; Kuster, Niels; Kainz, Wolfgang; Guag, Joshua W; Hahn, Eckhart G; Rascher, Wolfgang; Janka, Rolf; Bautz, Werner; Chen, Ji; Shen, Jianxiang; Kiefer, Berthold; Schmitt, Peter; Hollenbach, Hans-Peter; Kam, Anthony

    2010-01-01

    The objective of this study was to develop anatomically correct whole body human models of an adult male (34 years old), an adult female (26 years old) and two children (an 11-year-old girl and a six-year-old boy) for the optimized evaluation of electromagnetic exposure. These four models are referred to as the Virtual Family. They are based on high resolution magnetic resonance (MR) images of healthy volunteers. More than 80 different tissue types were distinguished during the segmentation. To improve the accuracy and the effectiveness of the segmentation, a novel semi-automated tool was used to analyze and segment the data. All tissues and organs were reconstructed as three-dimensional (3D) unstructured triangulated surface objects, yielding high precision images of individual features of the body. This greatly enhances the meshing flexibility and the accuracy with respect to thin tissue layers and small organs in comparison with the traditional voxel-based representation of anatomical models. Conformal computational techniques were also applied. The techniques and tools developed in this study can be used to more effectively develop future models and further improve the accuracy of the models for various applications. For research purposes, the four models are provided for free to the scientific community. (note)

  12. Motion as perturbation. II. Development of the method for dosimetric analysis of motion effects with fixed-gantry IMRT

    Energy Technology Data Exchange (ETDEWEB)

    Nelms, Benjamin E. [Canis Lupus LLC, Merrimac, Wisconsin 53561 (United States); Opp, Daniel; Zhang, Geoffrey; Moros, Eduardo; Feygelman, Vladimir, E-mail: vladimir.feygelman@moffitt.org [Department of Radiation Oncology, Moffitt Cancer Center, Tampa, Florida 33612 (United States)

    2014-06-15

    Purpose: In this work, the feasibility of implementing a motion-perturbation approach to accurately estimate volumetric dose in the presence of organ motion—previously demonstrated for VMAT-–is studied for static gantry IMRT. The method's accuracy is improved for the voxels that have very low planned dose but acquire appreciable dose due to motion. The study describes the modified algorithm and its experimental validation and provides an example of a clinical application. Methods: A contoured region-of-interest is propagated according to the predefined motion kernel throughout time-resolved 4D phantom dose grids. This timed series of 3D dose grids is produced by the measurement-guided dose reconstruction algorithm, based on an irradiation of a staticARCCHECK (AC) helical dosimeter array (Sun Nuclear Corp., Melbourne, FL). Each moving voxel collects dose over the dynamic simulation. The difference in dose-to-moving voxel vs dose-to-static voxel in-phantom forms the basis of a motion perturbation correction that is applied to the corresponding voxel in the patient dataset. A new method to synchronize the accelerator and dosimeter clocks, applicable to fixed-gantry IMRT, was developed. Refinements to the algorithm account for the excursion of low dose voxels into high dose regions, causing appreciable dose increase due to motion (LDVE correction). For experimental validation, four plans using TG-119 structure sets and objectives were produced using segmented IMRT direct machine parameters optimization in Pinnacle treatment planning system (v. 9.6, Philips Radiation Oncology Systems, Fitchburg, WI). All beams were delivered with the gantry angle of 0°. Each beam was delivered three times: (1) to the static AC centered on the room lasers; (2) to a static phantom containing a MAPCHECK2 (MC2) planar diode array dosimeter (Sun Nuclear); and (3) to the moving MC2 phantom. The motion trajectory was an ellipse in the IEC XY plane, with 3 and 1.5 cm axes. The period

  13. Dosimetric verification of IMRT plans

    International Nuclear Information System (INIS)

    Bulski, W.; Cheimicski, K.; Rostkowska, J.

    2012-01-01

    Intensity modulated radiotherapy (IMRT) is a complex procedure requiring proper dosimetric verification. IMRT dose distributions are characterized by steep dose gradients which enable to spare organs at risk and allow for an escalation of the dose to the tumor. They require large number of radiation beams (sometimes over 10). The fluence measurements for individual beams are not sufficient for evaluation of the total dose distribution and to assure patient safety. The methods used at the Centre of Oncology in Warsaw are presented. In order to measure dose distributions in various cross-sections the film dosimeters were used (radiographic Kodak EDR2 films and radiochromic Gafchromic EBT films). The film characteristics were carefully examined. Several types of tissue equivalent phantoms were developed. A methodology of comparing measured dose distributions against the distributions calculated by treatment planning systems (TPS) was developed and tested. The tolerance level for this comparison was set at 3% difference in dose and 3 mm in distance to agreement. The so called gamma formalism was used. The results of these comparisons for a group of over 600 patients are presented. Agreement was found in 87 % of cases. This film dosimetry methodology was used as a benchmark to test and validate the performance of commercially available 2D and 3D matrices of detectors (ionization chambers or diodes). The results of these validations are also presented. (authors)

  14. Literacy Skill Development of Children with Familial Risk for Dyslexia through Grades 2, 3, and 8

    Science.gov (United States)

    Eklund, Kenneth; Torppa, Minna; Aro, Mikko; Leppänen, Paavo H. T.; Lyytinen, Heikki

    2015-01-01

    This study followed the development of reading speed, reading accuracy, and spelling in transparent Finnish orthography in children through Grades 2, 3, and 8. We compared 2 groups of children with familial risk for dyslexia--1 group with dyslexia (Dys _FR, n = 35) and 1 group without (NoDys_FR, n = 66) in Grade 2--with a group of children without…

  15. The Development of Working Memory from Kindergarten to First Grade in Children with Different Decoding Skills

    Science.gov (United States)

    Nevo, Einat; Breznitz, Zvia

    2013-01-01

    This study investigated the development of working memory ability (measured by tasks assessing all four working memory components) from the end of kindergarten to the end of first grade--the first year reading is taught in school--and the relationship between working memory abilities in kindergarten and first grade and reading skills in first…

  16. Intensity modulated radiotherapy of upper abdominal malignancies: dosimetric comparison with 3D conformal radiotherapy and acute toxicity

    International Nuclear Information System (INIS)

    Nour, Alaa Ahmad; Alaradi, Aziz; Mohamed, Adel; Altuwaijri, Saleh; Rudat, Volker

    2013-01-01

    The goal of this study was to assess a possible dosimetric advantage of intensity modulated radiotherapy (IMRT) of upper abdominal malignancies compared to three-dimensional conformal radiotherapy (3DCRT), and to assess the impact of IMRT on acute toxicity. Thirty-one unselected consecutive patients with upper abdominal malignancies were treated with definitive (n =16) or postoperative (n =15) IMRT. Twenty-one patients (67.7%) received concomitant chemotherapy. 3DCRT plans were generated for comparison, and analysis of variance (ANOVA) for repeated measurements was used to test for significant difference of dosimetric parameters. Acute toxicity was assessed weekly using the Common Terminology Criteria for Adverse Events (CTCAE) grading scale. IMRT plans showed a small but statistically significant improvement of the conformity index compared to 3DCRT plans (difference (95% confidence interval), -0.06 (−0.109 to-0.005); p = 0.03). The homogeneity index was not significantly improved (p = 0.10). A significantly reduced high dose volume on cost of a significantly increased low dose volume was observed for the kidneys. The acute toxicity appeared to be less than commonly reported for corresponding patients treated with 3DCRT. No patient developed grade 3 or 4 non-hematological acute toxicity, and the most common grade 2 toxicity was vomiting (9.7%). IMRT offers the potential of a clinically relevant dosimetric advantage compared to 3DCRT in terms of a reduced acute toxicity. Further optimization of the radiotherapy technique and more clinical trials are required before IMRT is routinely used for upper abdominal malignancies

  17. Dosimetric essay in dental radiology

    International Nuclear Information System (INIS)

    Lopez Salaberry, M.

    1998-01-01

    A neck study was observated in the tiroids glands,laryngeal zone, sensitive organs for the ionizing radiation for increase dental xray exams. Was selected 29th patients with radiography prescription complete (in the Odontology Faculty Clinics Uruguaian). It took radiographies with and without tiroids necklace and apron lead using dosemeters. Dosimetric studies had demonstrated good dose between patients. For measuring the radiation dose have been used TLD thermoluminescence dosimetric and Harshaw 6600 for read it. The thyroids necklace use and odontology postgrading for training course for dentistry was the two recommendations advised

  18. Dosimetric characterization of the Exradin W1 plastic scintillator detector through comparison with an in-house developed scintillator system. / Beierholm, Anders Ravnsborg

    DEFF Research Database (Denmark)

    Beierholm, Anders Ravnsborg; Behrens, Claus Flensted; Andersen, Claus E.

    2014-01-01

    method, but differing primarily in the signal detection hardware. The two systems were compared with respect to essential dosimetric properties, with the purpose of testing their performance under conditions less well discussed in the literature. A Farmer ionization chamber was used as the primary...... is therefore advised if using either system for measurements in large fields or under circumstances where the fibre irradiation geometry is unfavourable. Measurements of reference dose to water yielded differences up to 1.5% when compared with the Farmer ionization chamber for all investigated beam qualities....

  19. Development of W/Cu--functionally graded materials

    International Nuclear Information System (INIS)

    Pintsuk, G.; Bruenings, S.E.; Doering, J.-E.; Linke, J.; Smid, I.; Xue, L.

    2003-01-01

    Plasma facing components (PFCs) consist of a plasma facing and a heat sink material. These have to fulfil different functions that require different material properties, for example the coefficient of thermal expansion (CTE) of tungsten and copper. Joining of these materials (e.g. by brazing or HIPing) results in the formation of thermal-induced stresses at the interface. Functionally graded materials (FGMs), used as an interlayer, reduce these thermally induced stresses. Two different methods, laser sintering and plasma spraying, have been investigated as a means to produce W/Cu FGMs to be used in PFCs of next step confinement experiments. In addition to mixtures of tungsten and copper powders, 40 wt.% Cu-coated W powder was used to produce W/Cu composites with a content of either 25 or 60 vol.% Cu. The composite microstructure has been analyzed according to Cu content, particle distribution and layer structure. The difference in the behavior of powder mixtures and coated powder is outlined. A comparison of plasma sprayed to commercially produced Cu-infiltrated W samples is made and the results of thermomechanical and thermophysical testing are discussed with respect to different microstructures

  20. Dosimetric predictors of radiation-induced pericardial effusion in esophageal cancer

    International Nuclear Information System (INIS)

    Ogino, Ichiro; Watanabe, Shigenobu; Sakamaki, Kentaro; Ogino, Yuka; Kunisaki, Chikara; Kimura, Kazuo

    2017-01-01

    To evaluate the dose-volume parameters of the pericardium and heart in order to reduce the risk of radiation-induced pericardial effusion (PE) and symptomatic PE (SPE) in esophageal cancer patients treated with concurrent chemoradiotherapy. In 86 of 303 esophageal cancer patients, follow-up CT was obtained at least 24 months after concurrent chemoradiotherapy. Correlations between clinical factors, including risk factors for cardiac disease, dosimetric factors, and the incidence of PE and SPE after radiotherapy were analyzed using Cox proportional hazard regression analysis. Significant dosimetric factors with the highest hazard ratios were investigated using zones separated according to their distance from esophagus. PE developed in 49 patients. Univariate analysis showed the mean heart dose, heart V 5 -V 55 , mean pericardium dose, and pericardium V 5 -V 50 to all significantly affect the incidence of PE. Additionally, body surface area was correlated with the incidence of PE in multivariate analysis. Grade 3 and 4 SPE developed in 5 patients. The pericardium V 50 and pericardium D 10 significantly affected the incidence of SPE. The pericardium V 50 in patients with SPE ranged from 17.1 to 21.7%. Factors affecting the incidence of SPE were the V 50 of the pericardium zones within 3 cm and 4 cm of the esophagus. A wide range of radiation doses to the heart and pericardium were related to the incidence of PE. A pericardium V 50 ≤ 17% is important to avoid symptomatic PE in esophageal cancer patients treated with concurrent chemoradiotherapy. (orig.) [de

  1. The association between school exam grades and subsequent development of bipolar disorder

    DEFF Research Database (Denmark)

    Pedersen, Steffie Damgaard; Østergaard, Søren Dinesen; Petersen, Liselotte

    2018-01-01

    and bipolar I disorder (BD-I) has not been studied. Therefore, we aimed to study the association between school exam grades and subsequent development of BD and BD-I while adjusting for parental history of mental disorder. METHODS: We conducted a register-based nationwide cohort study following 505 688......OBJECTIVE: Prior studies have indicated that both high and low school grades are associated with development of bipolar disorder (BD), but these studies have not adjusted for parental history of mental disorder, which is a likely confounder. Furthermore, the association between school grades...... individuals born in Denmark between 1987 and 1995. We investigated the association between school exam grades and development of BD or BD-I with a Cox model adjusting for family history of mental disorder and other potential confounders. RESULTS: During follow-up, 900 individuals were diagnosed with BD...

  2. Peculiarities of Evaluation of Motor Abilities Development in 10th-11th-Grade Boys

    OpenAIRE

    В. М. Старченко

    2016-01-01

    The purpose of the research is to determine the main indicators of motor abilities development in the 10th-11th-grade boys. Materials and methods. To achieve the tasks set, the research relied on the following methods: analysis of scientific and methodological literature, pedagogical testing and methods of mathematical statistics. The participants in the study were 28 high-school boys (14 boys of the 10th-grade and 14 boys of the 11th-grade). Conclusions. The general level of motor re...

  3. Linguistic Pattern Analysis of Misspellings of Typically Developing Writers in Grades 1 to 9

    Science.gov (United States)

    Bahr, Ruth Huntley; Silliman, Elaine R.; Berninger, Virginia W.; Dow, Michael

    2012-01-01

    Purpose A mixed methods approach, evaluating triple word form theory, was used to describe linguistic patterns of misspellings. Method Spelling errors were taken from narrative and expository writing samples provided by 888 typically developing students in grades 1–9. Errors were coded by category (phonological, orthographic, and morphological) and specific linguistic feature affected. Grade level effects were analyzed with trend analysis. Qualitative analyses determined frequent error types and how use of specific linguistic features varied across grades. Results Phonological, orthographic, and morphological errors were noted across all grades, but orthographic errors predominated. Linear trends revealed developmental shifts in error proportions for the orthographic and morphological categories between grades 4–5. Similar error types were noted across age groups but the nature of linguistic feature error changed with age. Conclusions Triple word-form theory was supported. By grade 1, orthographic errors predominated and phonological and morphological error patterns were evident. Morphological errors increased in relative frequency in older students, probably due to a combination of word-formation issues and vocabulary growth. These patterns suggest that normal spelling development reflects non-linear growth and that it takes a long time to develop a robust orthographic lexicon that coordinates phonology, orthography, and morphology and supports word-specific, conventional spelling. PMID:22473834

  4. The Development of CBM Vocabulary Measures: Grade 8. Technical Report #1215

    Science.gov (United States)

    Alonzo, Julie; Anderson, Daniel; Park, Bitnara Jasmine; Tindal, Gerald

    2012-01-01

    In this technical report, we describe the development and piloting of a series of vocabulary assessments intended for use with students in grades two through eight. These measures, available as part of easyCBM[TM], an online progress monitoring and benchmark/screening assessment system, were developed in 2010 and administered to approximately 1200…

  5. The Development of CBM Vocabulary Measures: Grade 7. Technical Report #1214

    Science.gov (United States)

    Alonzo, Julie; Anderson, Daniel; Park, Bitnara Jasmine; Tindal, Gerald

    2012-01-01

    In this technical report, we describe the development and piloting of a series of vocabulary assessments intended for use with students in grades two through eight. These measures, available as part of easyCBM[TM], an online progress monitoring and benchmark/screening assessment system, were developed in 2010 and administered to approximately 1200…

  6. The Development of CBM Vocabulary Measures: Grade 4. Technical Report #1211

    Science.gov (United States)

    Alonzo, Julie; Anderson, Daniel; Park, Bitnara Jasmine; Tindal, Gerald

    2012-01-01

    In this technical report, we describe the development and piloting of a series of vocabulary assessments intended for use with students in grades two through eight. These measures, available as part of easyCBM[TM], an online progress monitoring and benchmark/screening assessment system, were developed in 2010 and administered to approximately 1200…

  7. The Development of CBM Vocabulary Measures: Grade 5. Technical Report #1212

    Science.gov (United States)

    Alonzo, Julie; Anderson, Daniel; Park, Bitnara Jasmine; Tindal, Gerald

    2012-01-01

    In this technical report, we describe the development and piloting of a series of vocabulary assessments intended for use with students in grades two through eight. These measures, available as part of easyCBM[TM], an online progress monitoring and benchmark/screening assessment system, were developed in 2010 and administered to approximately 1200…

  8. The Development of CBM Vocabulary Measures: Grade 2. Technical Report #1209

    Science.gov (United States)

    Alonzo, Julie; Anderson, Daniel; Park, Bitnara Jasmine; Tindal, Gerald

    2012-01-01

    In this technical report, we describe the development and piloting of a series of vocabulary assessments intended for use with students in grades two through eight. These measures, available as part of easyCBM[TM], an online progress monitoring and benchmark/screening assessment system, were developed in 2010 and administered to approximately 1200…

  9. The Development of CBM Vocabulary Measures: Grade 6. Technical Report # 1213

    Science.gov (United States)

    Alonzo, Julie; Anderson, Daniel; Park, Bitnara Jasmine; Tindal, Gerald

    2012-01-01

    In this technical report, we describe the development and piloting of a series of vocabulary assessments intended for use with students in grades two through eight. These measures, available as part of easyCBM[TM], an online progress monitoring and benchmark/screening assessment system, were developed in 2010 and administered to approximately 1200…

  10. The Development of CBM Vocabulary Measures: Grade 3. Technical Report #1210

    Science.gov (United States)

    Alonzo, Julie; Anderson, Daniel; Park, Bitnara Jasmine; Tindal, Gerald

    2012-01-01

    In this technical report, we describe the development and piloting of a series of vocabulary assessments intended for use with students in grades two through eight. These measures, available as part of easyCBM[TM], an online progress monitoring and benchmark/screening assessment system, were developed in 2010 and administered to approximately 1200…

  11. Development of 780MPa grade gal annealed dual phase steel sheets for automobile

    Science.gov (United States)

    Jiang, Yinghua; Xie, Chunqian; Kuang, Shuang

    2018-01-01

    As the weight reduction of automotive body and crash safety become much more important factors, in an effort to satisfy these requirements, Shougang has developed 780MPa grade galvannealed dual phase steel sheet. Steel chemistry with low C and low Si was designed for good zinc wettability and spot weldability. And some of elements were added to improve the hole expansibility and work hardening capacity of steel as these effectively refine the microstructure and introduce retained austenite. Newly developed 780MPa grade galvannealed dual phase steels have a high yield strength and a good hole expansibility.

  12. SU-E-T-109: Development of An End-To-End Test for the Varian TrueBeamtm with a Novel Multiple-Dosimetric Modality H and N Phantom

    Energy Technology Data Exchange (ETDEWEB)

    Zakjevskii, V; Knill, C; Rakowski, J; Snyder, M [Wayne State University, Karmanos Cancer Institute, Detroit, MI (United States)

    2014-06-01

    Purpose: To develop a comprehensive end-to-end test for Varian's TrueBeam linear accelerator for head and neck IMRT using a custom phantom designed to utilize multiple dosimetry devices. Methods: The initial end-to-end test and custom H and N phantom were designed to yield maximum information in anatomical regions significant to H and N plans with respect to: i) geometric accuracy, ii) dosimetric accuracy, and iii) treatment reproducibility. The phantom was designed in collaboration with Integrated Medical Technologies. A CT image was taken with a 1mm slice thickness. The CT was imported into Varian's Eclipse treatment planning system, where OARs and the PTV were contoured. A clinical template was used to create an eight field static gantry angle IMRT plan. After optimization, dose was calculated using the Analytic Anisotropic Algorithm with inhomogeneity correction. Plans were delivered with a TrueBeam equipped with a high definition MLC. Preliminary end-to-end results were measured using film and ion chambers. Ion chamber dose measurements were compared to the TPS. Films were analyzed with FilmQAPro using composite gamma index. Results: Film analysis for the initial end-to-end plan with a geometrically simple PTV showed average gamma pass rates >99% with a passing criterion of 3% / 3mm. Film analysis of a plan with a more realistic, ie. complex, PTV yielded pass rates >99% in clinically important regions containing the PTV, spinal cord and parotid glands. Ion chamber measurements were on average within 1.21% of calculated dose for both plans. Conclusion: trials have demonstrated that our end-to-end testing methods provide baseline values for the dosimetric and geometric accuracy of Varian's TrueBeam system.

  13. Dosimetric systems of high dose, dose rate and dose uniformity in food and medical products

    International Nuclear Information System (INIS)

    Vargas, J.; Vivanco, M.; Castro, E.

    2014-08-01

    In the Instituto Peruano de Energia Nuclear (IPEN) we use the chemical dosimetry Astm-E-1026 Fricke as a standard dosimetric system of reference and different routine dosimetric systems of high doses, according to the applied doses to obtain the desired effects in the treated products and the doses range determined for each type of dosimeter. Fricke dosimetry is a chemical dosimeter in aqueous solution indicating the absorbed dose by means an increase in absorbance at a specific wavelength. A calibrated spectrophotometer with controlled temperature is used to measure absorbance. The adsorbed dose range should cover from 20 to 400 Gy, the Fricke solution is extremely sensitive to organic impurities, to traces of metal ions, in preparing chemical products of reactive grade must be used and the water purity is very important. Using the referential standard dosimetric system Fricke, was determined to March 5, 2013, using the referential standard dosimetric system Astm-1026 Fricke, were irradiated in triplicate Fricke dosimeters, to 5 irradiation times (20; 30; 40; 50 and 60 seconds) and by linear regression, the dose rate of 5.400648 kGy /h was determined in the central point of the irradiation chamber (irradiator Gamma cell 220 Excel), applying the decay formula, was compared with the obtained results by manufacturers by means the same dosimetric system in the year of its manufacture, being this to the date 5.44691 kGy /h, with an error rate of 0.85. After considering that the dosimetric solution responds to the results, we proceeded to the irradiation of a sample of 200 g of cereal instant food, 2 dosimeters were placed at the lateral ends of the central position to maximum dose and 2 dosimeters in upper and lower ends as minimum dose, they were applied same irradiation times; for statistical analysis, the maximum dose rate was 6.1006 kGy /h and the minimum dose rate of 5.2185 kGy /h; with a dose uniformity of 1.16. In medical material of micro pulverized bone for

  14. Dosimetric rationale and early experience at UFPTI of thoracic proton therapy and chemotherapy in limited-stage small cell lung cancer

    Energy Technology Data Exchange (ETDEWEB)

    Colaco, Rovel J.; Huh, Soon; Nichols, Romaine; Morris, Christopher G.; Flampouri, Stella; Li, Zuofeng; Hoppe, Bradford S. [Univ. of Florida Proton Therapy Inst., Jacksonville (United States)], e-mail: bhoppe@floridaproton.org; D' Agostino, Harry [Dept. of Thoracic Surgery, Univ. of Florida Coll. of Medicine, Gainesville (United States); Pham, Dat C. [Dept. of Hematology and Medical Oncology, Univ. of Florida Coll. of Medicine, Gainesville (United States); Bajwa, Abubakr A. [Dept. of Medicine, Univ. of Florida Coll. of Medicine, Gainesville (United States)

    2013-04-15

    Background: Concurrent chemoradiotherapy (CRT) is the standard of care in patients with limited-stage small cell lung cancer (SCLC). Treatment with conventional x-ray therapy (XRT) is associated with high toxicity rates, particularly acute grade 3+ esophagitis and pneumonitis. We present outcomes for the first known series of limited-stage SCLC patients treated with proton therapy and a dosimetric comparison of lung and esophageal doses with intensity-modulated radiation therapy (IMRT). Material and methods: Six patients were treated; five concurrently and one sequentially. Five patients received 60-66 CGE in 30-34 fractions once daily and one patient received 45 CGE in 30 fractions twice daily. All six patients received prophylactic cranial irradiation. Common Terminology Criteria for Adverse Events, v3.0, was used to grade toxicity. IMRT plans were also generated and compared with proton plans. Results: The median follow-up was 12.0 months. The one-year overall and progression-free survival rates were 83% and 66%, respectively. There were no cases of acute grade 3+ esophagitis or acute grade 2+ pneumonitis, and no other acute grade 3+ non-hematological toxicities were seen. One patient with a history of pulmonary fibrosis and atrial fibrillation developed worsening symptoms four months after treatment requiring oxygen. Three patients died; two of progressive disease and one after a fall. The latter patient was disease-free at 36 months after treatment. Another patient recurred and is alive, while two patients remain disease-free at 12 months of follow-up. Proton therapy proved superior to IMRT across all esophageal and lung dose volume points. Conclusion. In this small series of SCLC patients treated with proton therapy with radical intent, treatment was well tolerated with no cases of acute grade 3+ esophagitis or acute grade 2+ pneumonitis. Dosimetric comparison showed better sparing of lung and esophagus with proton therapy. Proton therapy merits further

  15. Exergame Grading Scheme: Concept Development and Preliminary Psychometric Evaluations in Cancer Survivors

    Directory of Open Access Journals (Sweden)

    Hsiao-Lan Wang

    2017-01-01

    Full Text Available The challenge of using exergames to promote physical activity among cancer survivors lies in the selection of the exergames that match their fitness level. There is a need for a standardized grading scheme by which to judge an exergame’s capacity to address specific physical fitness attributes with different levels of physical engagement. The study aimed to develop an Exergame Grading Scheme and preliminarily evaluate its psychometric properties. Fourteen (14 items were created from the human movement and exergame literature. The content validity index (CVI was rated by content experts with two consecutive rounds (N=5 and N=3 independently. The interrater reliability (IRR was determined by two raters who used the Exergame Grading Scheme to determine the grading score of the five exergames performed by two cancer survivors (N=10. Each item had a score of 1 for item-level CVI and 1 for k. For IRR, 9 items had rho values of 1, 1 item had 0.93, and 4 items had between 0.80 and 0.89. This valid and reliable Exergame Grading Scheme makes it possible to develop a personalized physical activity program using any type of exergame or fitness mobile application in rehabilitation practice to meet the needs of cancer survivors.

  16. Study of a new dosimetric radio-thermoluminescent systems

    International Nuclear Information System (INIS)

    Cazac, T.C.

    1980-01-01

    This is the first Romanian study to investigate conditions to obtain the radio-thermo-luminescent systems: MgB 4 O 7 :A(A-Nd,Sm,Eu,Dy,Tb,Dy+Sm and Tb+Sm) MgF 2 A (A=Mn,Dy,Tb,Sm,Li), their essential dosimetric characters, as well as the (MgF 2 =Mn) thermophosphorus mixture with a ( 6 LiF) lithium target. An investigation was developed upon a new category of radio-thermoluminescent detectors with low radiation energy dependence and fading, magnesjum boride activated by several elements of the lanthanides class (Nd,Sm,Eu,Dy,Tb). A new radio-thermoluminescent dosimetric system with high sensitivity and moderate dependence on energy radiation - (Mnsup(2+)) manganese activated magnesium fluoride - was also studied. The author explored application of investigated detectors MgF 2 =Mn, MgB 4 O 7 =Dy and MgB 4 O 7 :Tb in neutron dosimetry in complex gamma-neutron fields. It is deemed that by using the dosimetric systems reported in the thesis in order to measure gamma, beta and neutron radiation doses, dosimetric control can be ensured both in professional dosimetry and in nuclear accident dosimetry, as well as in various basic and applicative investigations. A modest contribution is thus made towards achieving the national nuclear program through an extension of the thermophosphorus range with practical applications in nuclear radiation dosimetry. (author)

  17. Analysis of superficial fluorescence patterns in nonmelanoma skin cancer during photodynamic therapy by a dosimetric model

    Science.gov (United States)

    Salas-García, I.; Fanjul-Vélez, F.; Arce-Diego, J. L.

    2016-03-01

    In this work the superficial fluorescence patterns in different nonmelanoma skin cancers and their photodynamic treatment response are analysed by a fluorescence based dosimetric model. Results show differences of even more than 50% in the fluorescence patterns as photodynamic therapy progresses depending on the malignant tissue type. They demonstrate the great relevance of the biological media as an additional dosimetric factor and contribute to the development of a future customized therapy with the assistance of dosimetric tools to interpret the fluorescence images obtained during the treatment monitoring and the differential photodiagnosis.

  18. CaSO4: Dy + Teflon dosimetric pellets for X, beta and gamma radiation detection

    International Nuclear Information System (INIS)

    Campos, L.L.; Lima, M.F.

    1987-08-01

    CaSO 4 : Dy + TEFLON dosimetric pellets with high sensitivity and low cost for X, beta and gamma radiation monitoring were studied and developed by the Dosimetric Material Production Laboratory of the Radiological Protection Departament and are disposable for sale. The thickness of the pellets are suitable for X, beta and gamma radiation measurements. The dosimetric properties of these pellets were determined and presented in this work. The results show the usefulness of 0,20mm thick pellets for beta radiation monitoring and 0,80mm thick pellets for x and gamma radiation detection. (Author) [pt

  19. The Use of Retelling Stories Technique in Developing English Speaking Ability of Grade 9 Students

    Science.gov (United States)

    Praneetponkrang, Sasitorn; Phaiboonnugulkij, Malinee

    2014-01-01

    This article aims to advocate retelling stories technique for developing speaking ability of grade 9 students in Thailand. Morrow's theory (1981) and other scholars in retelling stories technique are presented. This technique is integrated in the lesson plans following Morrow's framework. Narrative text of short stories which refer to daily life…

  20. Semantic categorization and reading skill across Dutch primary grades: development yes, relationship no

    NARCIS (Netherlands)

    Gijsel, M.A.R.; Ormel, E.A.; Hermans, D.; Verhoeven, L.T.W.; Bosman, A.M.T.

    2011-01-01

    In the present study, the development of semantic categorization and its relationship with reading was investigated across Dutch primary grade students. Three Exemplar-level tasks (Experiment 1) and two Superordinate-level tasks (Experiment 2) with different types of distracters (phonological,

  1. 7th Grade Students' Mental Models about the Concept of "Sustainable Development"

    Science.gov (United States)

    Keles, Özgül; Eris, Rabia; Aydogdu, Mustafa

    2017-01-01

    The purpose of the current study is to elicit the opinions constructed by 7th grade secondary school students about three components of the concept of sustainable development; environment, society and economy. Study group of the implementation consists of 20 students attending a public secondary school in 2014-2015 academic year. The study…

  2. Visual Literacy Development through the Mediation of Grade 4 English Textbooks

    Science.gov (United States)

    Sibanda, Jabulani; Sibanda, Lucy

    2013-01-01

    The multimodal world learners inhabit demands visual literacy among other literacies if learners are to effectively navigate its terrain. In this study, we sought to understand the extent to which five Grade 4 English textbooks currently used in some schools in the Eastern Cape province of South Africa facilitated the development of visual…

  3. Development of the Teacher Assessment of Student Communicative Competence (TASCC) for Grades 1 through 5.

    Science.gov (United States)

    Smith, Ann R.; McCauley, Rebecca; Guitar, Barry

    2000-01-01

    This article describes the development and possible applications of the Teacher Assessment of Student Communicative Competencies (TASCC) for use with students in the first through fifth grades. The TASCC allowed 20 teachers to successfully observe and measure their students' verbal and nonverbal communicative abilities and use of compensatory…

  4. Developing Global Competency Skills in Grades 9-12: Implications for School Leadership

    Science.gov (United States)

    Staudt, Bettina

    2016-01-01

    The purpose of the phenomenological study was to examine and understand public high schools, grades 9-12, which have implemented the full integration of global competency skills as an integral part of their core mission. This study also explored, how school leaders ensured that global competency skills are developed, implemented and integrated…

  5. Linguistic Pattern Analysis of Misspellings of Typically Developing Writers in Grades 1-9

    Science.gov (United States)

    Bahr, Ruth Huntley; Silliman, Elaine R.; Berninger, Virginia W.; Dow, Michael

    2012-01-01

    Purpose: A mixed-methods approach, evaluating triple word-form theory, was used to describe linguistic patterns of misspellings. Method: Spelling errors were taken from narrative and expository writing samples provided by 888 typically developing students in Grades 1-9. Errors were coded by category (phonological, orthographic, and morphological)…

  6. The Development of a Model for Creative Writing Instruction for Mattayomsuksa Three Students (Grade 9)

    Science.gov (United States)

    Chaiyadejkamjorn, Natsuchawirang; Soonthonrojana, Wimonrat; Sangkhaphanthanon, Thanya

    2017-01-01

    The research aimed to construct an instructional model for creative writing for Mattayomsueksa Three students (Grade 9), to develop the model according to a criterion of 80/80, and to examine the results of the model in use. The research methodology consisted of three phases: phase one studied the current states, problems and needs for teaching…

  7. Research and development of intelligent controller for high-grade sanitary ware

    Science.gov (United States)

    Bao, Kongjun; Shen, Qingping

    2013-03-01

    With the social and economic development and people's living standards improve, more and more emphasis on modern society, people improve the quality of family life, the use of intelligent controller applications in high-grade sanitary ware physiotherapy students. Analysis of high-grade sanitary ware physiotherapy common functions pointed out in the production and use of the possible risks, proposed implementation of the system hardware and matching, given the system software implementation process. High-grade sanitary ware physiotherapy intelligent controller not only to achieve elegant and beautiful, simple, physical therapy, water power, deodorant, multi-function, intelligent control, to meet the consumers, the high-end sanitary ware market, strong demand, Accelerate the enterprise product Upgrade and improve the competitiveness of enterprises.

  8. Dosimetric study for characterization of a postal system of quality control in brachytherapy

    International Nuclear Information System (INIS)

    Alves, Victor Gabriel Leandro; Queiroz Filho, Pedro Pacheco de; Santos, Denison de Souza; Begalli, Marcia

    2009-01-01

    This work presents a dosimetric study of a postal system, to be developed for measurements of brachytherapy. It was projected a PMMA phantom with orifices for insertion of the high dose 192 Ir source and the T L dosemeters. The system was characterized with using of Monte Carlo simulations, using the dosimetric magnitudes defined at the T G-43 of AAPM, as function of radial dose g(f)

  9. Development of Writing Knowledge in Grades 2-8: A Comparison of Typically Developing Writers and Their Struggling Peers

    Science.gov (United States)

    Lin, Shin-Ju Cindy; Monroe, Brandon W.; Troia, Gary A.

    2007-01-01

    This study examined student perspectives about writing by interviewing both typically developing and struggling writers in Grades 2 through 8. The findings revealed a progressive developmental pattern of writing knowledge in which novice writers place more emphasis on the physical product and local meaning, while more experienced writers focus on…

  10. Dosimetric predictors of radiation-induced acute nausea and vomiting in IMRT for nasopharyngeal cancer.

    Science.gov (United States)

    Lee, Victor H F; Ng, Sherry C Y; Leung, T W; Au, Gordon K H; Kwong, Dora L W

    2012-09-01

    We wanted to investigate dosimetric parameters that would predict radiation-induced acute nausea and vomiting in intensity-modulated radiation therapy (IMRT) for undifferentiated carcinoma of the nasopharynx (NPC). Forty-nine consecutive patients with newly diagnosed NPC were treated with IMRT alone in this prospective study. Patients receiving any form of chemotherapy were excluded. The dorsal vagal complex (DVC) as well as the left and right vestibules (VB-L and VB-R, respectively) were contoured on planning computed tomography images. A structure combining both the VB-L and the VB-R, named VB-T, was also generated. All structures were labeled organs at risk (OAR). A 3-mm three-dimensional margin was added to these structures and labeled DVC+3 mm, VB-L+3 mm, VB-R+3 mm, and VB-T+3 mm to account for physiological body motion and setup error. No weightings were given to these structures during optimization in treatment planning. Dosimetric parameters were recorded from dose-volume histograms. Statistical analysis of parameters' association with nausea and vomiting was performed using univariate and multivariate logistic regression. Six patients (12.2%) reported Grade 1 nausea, and 8 patients (16.3%) reported Grade 2 nausea. Also, 4 patients (8.2%) complained of Grade 1 vomiting, and 4 patients (8.2%) experienced Grade 2 vomiting. No patients developed protracted nausea and vomiting after completion of IMRT. For radiation-induced acute nausea, V40 (percentage volume receiving at least 40Gy) to the VB-T and V40>=80% to the VB-T were predictors, using univariate analysis. On multivariate analysis, V40>=80% to the VB-T was the only predictor. There were no predictors of radiation-induced acute vomiting, as the number of events was too small for analysis. This is the first study demonstrating that a V40 to the VB-T is predictive of radiation-induced acute nausea. The vestibules should be labeled as sensitive OARs, and weightings should be considered for dose sparing

  11. Dosimetric Predictors of Radiation-induced Acute Nausea and Vomiting in IMRT for Nasopharyngeal Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Victor H.F., E-mail: vhflee@hku.hk [Department of Clinical Oncology, University of Hong Kong, Queen Mary Hospital (Hong Kong); Ng, Sherry C.Y.; Leung, T.W.; Au, Gordon K.H.; Kwong, Dora L.W. [Department of Clinical Oncology, University of Hong Kong, Queen Mary Hospital (Hong Kong)

    2012-09-01

    Purpose: We wanted to investigate dosimetric parameters that would predict radiation-induced acute nausea and vomiting in intensity-modulated radiation therapy (IMRT) for undifferentiated carcinoma of the nasopharynx (NPC). Methods and Materials: Forty-nine consecutive patients with newly diagnosed NPC were treated with IMRT alone in this prospective study. Patients receiving any form of chemotherapy were excluded. The dorsal vagal complex (DVC) as well as the left and right vestibules (VB-L and VB-R, respectively) were contoured on planning computed tomography images. A structure combining both the VB-L and the VB-R, named VB-T, was also generated. All structures were labeled organs at risk (OAR). A 3-mm three-dimensional margin was added to these structures and labeled DVC+3 mm, VB-L+3 mm, VB-R+3 mm, and VB-T+3 mm to account for physiological body motion and setup error. No weightings were given to these structures during optimization in treatment planning. Dosimetric parameters were recorded from dose-volume histograms. Statistical analysis of parameters' association with nausea and vomiting was performed using univariate and multivariate logistic regression. Results: Six patients (12.2%) reported Grade 1 nausea, and 8 patients (16.3%) reported Grade 2 nausea. Also, 4 patients (8.2%) complained of Grade 1 vomiting, and 4 patients (8.2%) experienced Grade 2 vomiting. No patients developed protracted nausea and vomiting after completion of IMRT. For radiation-induced acute nausea, V40 (percentage volume receiving at least 40Gy) to the VB-T and V40>=80% to the VB-T were predictors, using univariate analysis. On multivariate analysis, V40>=80% to the VB-T was the only predictor. There were no predictors of radiation-induced acute vomiting, as the number of events was too small for analysis. Conclusions: This is the first study demonstrating that a V40 to the VB-T is predictive of radiation-induced acute nausea. The vestibules should be labeled as sensitive OARs

  12. Baking Industry. Grade 2. One in a Series of Career Development Curriculum Units for the Elementary Classroom. (Second Edition).

    Science.gov (United States)

    Barret, Jennifer; And Others

    Focusing on the occupational clusters of natural resources and manufacturing, this unit entitled "Baking Industry" is one of four grade 2 units which are part of a total set of twenty-seven career development curriculum units for grades K-6. This unit is organized into four sections. Section 1 identifies one career development-centered…

  13. Development of Safety Grade PLC (POSAFE-Q) and Performance Test Results

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Chang Hwoi; Park, Won Man; Choi, Jong Gyun; Lee, Dong Young [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of); No, Young Hun; Song, Seung Hwan [POSCON, Seoul (Korea, Republic of)

    2006-07-01

    The safety grade PLC (POSAFE-Q) is being developed in the Korea Nuclear Instrumentation and Control System (KNICS) R and D project. The PLC satisfies Safety Class 1E, Quality Class 1, and Seismic Category I. The software such as the RTOS and firmware are being developed according to the safety critical software life cycle. Especially, the formal method is applied to design the SRS (Software Requirement Spec.) and the SDS (Software Design Specification.) to be error-free. The POSAFE-Q has several modules such as processor module, input and output modules, communication modules, redundant processor module, redundant power modules, etc,. To verify the function and performance, several tests such as CT, IT and ST were performed. And also, the equipment qualification test for environment, EMI and EMC, and seismic ware performed. All tests are satisfied with the requirements and specification for safety grade PLC, and the criteria for safety system in nuclear power plants.

  14. How executive functions predict development in syntactic complexity of narrative writing in the upper elementary grades.

    Science.gov (United States)

    Drijbooms, Elise; Groen, Margriet A; Verhoeven, Ludo

    2017-01-01

    The aim of this study was to examine the contribution of transcription skills, oral language skills, and executive functions to growth in narrative writing between fourth and sixth grade. While text length and story content of narratives did not increase with age, syntactic complexity of narratives showed a clear developmental progression. Results from path analyses revealed that later syntactic complexity of narrative writing was, in addition to initial syntactic complexity, predicted by oral grammar, inhibition, and planning. These results are discussed in light of the changes that characterize writing development in the upper elementary grades. More specifically, this study emphasizes the relevance of syntactic complexity as a developmental marker as well as the importance of executive functions for later writing development.

  15. Flexibility development among 5–6th grade schoolchildren under the influence of cheerleading activity

    Directory of Open Access Journals (Sweden)

    Oleksandr Aghyppo

    2017-10-01

    Full Text Available Purpose: to determine the degree of change in the level of development of the flexibility of 5–6th grade schoolchildren under the influence of cheerleading activity. Material & Methods: 103 schoolchildren of 10–11 years took part in the research. Methods: theoretical analysis and generalization of scientific and methodological literature, pedagogical testing, pedagogical experiment and methods of mathematical statistics. Results: the indicators of the level of development of flexibility are presented, as well as the degree of their change under the influence of cheerleading activities among schoolchildren of the 5th and 6th grades of the general education school. Conclusion: the use of cheerleading activity positively influenced the degree of manifestation of the flexibility of schoolchildren of middle classes in all the parameters studied.

  16. IPIP: A new approach to inverse planning for HDR brachytherapy by directly optimizing dosimetric indices

    International Nuclear Information System (INIS)

    Siauw, Timmy; Cunha, Adam; Atamtuerk, Alper; Hsu, I-Chow; Pouliot, Jean; Goldberg, Ken

    2011-01-01

    Purpose: Many planning methods for high dose rate (HDR) brachytherapy require an iterative approach. A set of computational parameters are hypothesized that will give a dose plan that meets dosimetric criteria. A dose plan is computed using these parameters, and if any dosimetric criteria are not met, the process is iterated until a suitable dose plan is found. In this way, the dose distribution is controlled by abstract parameters. The purpose of this study is to develop a new approach for HDR brachytherapy by directly optimizing the dose distribution based on dosimetric criteria. Methods: The authors developed inverse planning by integer program (IPIP), an optimization model for computing HDR brachytherapy dose plans and a fast heuristic for it. They used their heuristic to compute dose plans for 20 anonymized prostate cancer image data sets from patients previously treated at their clinic database. Dosimetry was evaluated and compared to dosimetric criteria. Results: Dose plans computed from IPIP satisfied all given dosimetric criteria for the target and healthy tissue after a single iteration. The average target coverage was 95%. The average computation time for IPIP was 30.1 s on an Intel(R) Core TM 2 Duo CPU 1.67 GHz processor with 3 Gib RAM. Conclusions: IPIP is an HDR brachytherapy planning system that directly incorporates dosimetric criteria. The authors have demonstrated that IPIP has clinically acceptable performance for the prostate cases and dosimetric criteria used in this study, in both dosimetry and runtime. Further study is required to determine if IPIP performs well for a more general group of patients and dosimetric criteria, including other cancer sites such as GYN.

  17. IPIP: A new approach to inverse planning for HDR brachytherapy by directly optimizing dosimetric indices.

    Science.gov (United States)

    Siauw, Timmy; Cunha, Adam; Atamtürk, Alper; Hsu, I-Chow; Pouliot, Jean; Goldberg, Ken

    2011-07-01

    Many planning methods for high dose rate (HDR) brachytherapy require an iterative approach. A set of computational parameters are hypothesized that will give a dose plan that meets dosimetric criteria. A dose plan is computed using these parameters, and if any dosimetric criteria are not met, the process is iterated until a suitable dose plan is found. In this way, the dose distribution is controlled by abstract parameters. The purpose of this study is to develop a new approach for HDR brachytherapy by directly optimizing the dose distribution based on dosimetric criteria. The authors developed inverse planning by integer program (IPIP), an optimization model for computing HDR brachytherapy dose plans and a fast heuristic for it. They used their heuristic to compute dose plans for 20 anonymized prostate cancer image data sets from patients previously treated at their clinic database. Dosimetry was evaluated and compared to dosimetric criteria. Dose plans computed from IPIP satisfied all given dosimetric criteria for the target and healthy tissue after a single iteration. The average target coverage was 95%. The average computation time for IPIP was 30.1 s on an Intel(R) Core 2 Duo CPU 1.67 GHz processor with 3 Gib RAM. IPIP is an HDR brachytherapy planning system that directly incorporates dosimetric criteria. The authors have demonstrated that IPIP has clinically acceptable performance for the prostate cases and dosimetric criteria used in this study, in both dosimetry and runtime. Further study is required to determine if IPIP performs well for a more general group of patients and dosimetric criteria, including other cancer sites such as GYN.

  18. IPIP: A new approach to inverse planning for HDR brachytherapy by directly optimizing dosimetric indices

    Energy Technology Data Exchange (ETDEWEB)

    Siauw, Timmy; Cunha, Adam; Atamtuerk, Alper; Hsu, I-Chow; Pouliot, Jean; Goldberg, Ken [Department of Civil and Environmental Engineering, University of California, Berkeley, 760 Davis Hall, Berkeley, California 94720-1710 (United States); Department of Radiation Oncology, University of California, San Francisco, Comprehensive Cancer Center, 1600 Divisadero Street, Suite H1031, San Francisco, California 94143-1708 (United States); Department of Industrial Engineering and Operations, University of California, Berkeley, 4141 Etcheverry Hall, Berkeley, California 94720-1777 (United States); Department of Radiation Oncology, University of California, San Francisco, Comprehensive Cancer Center, 1600 Divisadero Street, Suite H1031, San Francisco, California 94143-1708 (United States); Department of Industrial Engineering and Operations Research and Department of Electrical Engineering and Computer Science, University of California, Berkeley, 4141 Etcheverry Hall, Berkeley, California 94720-1777 (United States)

    2011-07-15

    Purpose: Many planning methods for high dose rate (HDR) brachytherapy require an iterative approach. A set of computational parameters are hypothesized that will give a dose plan that meets dosimetric criteria. A dose plan is computed using these parameters, and if any dosimetric criteria are not met, the process is iterated until a suitable dose plan is found. In this way, the dose distribution is controlled by abstract parameters. The purpose of this study is to develop a new approach for HDR brachytherapy by directly optimizing the dose distribution based on dosimetric criteria. Methods: The authors developed inverse planning by integer program (IPIP), an optimization model for computing HDR brachytherapy dose plans and a fast heuristic for it. They used their heuristic to compute dose plans for 20 anonymized prostate cancer image data sets from patients previously treated at their clinic database. Dosimetry was evaluated and compared to dosimetric criteria. Results: Dose plans computed from IPIP satisfied all given dosimetric criteria for the target and healthy tissue after a single iteration. The average target coverage was 95%. The average computation time for IPIP was 30.1 s on an Intel(R) Core{sup TM}2 Duo CPU 1.67 GHz processor with 3 Gib RAM. Conclusions: IPIP is an HDR brachytherapy planning system that directly incorporates dosimetric criteria. The authors have demonstrated that IPIP has clinically acceptable performance for the prostate cases and dosimetric criteria used in this study, in both dosimetry and runtime. Further study is required to determine if IPIP performs well for a more general group of patients and dosimetric criteria, including other cancer sites such as GYN.

  19. Development of a dosimetric system for {sup 90}Sr + {sup 90}Y betatherapy applicators; Desenvolvimento de um sistema de dosimetria para aplicadores de betaterapia de {sup 90}Sr + {sup 90}Y

    Energy Technology Data Exchange (ETDEWEB)

    Coelho, Talita Salles

    2010-07-01

    The {sup 90}Sr+{sup 90}Y applicators, used in betatherapy for prevention of keloids and pterigium, are imported and many times their dosimetric features are shown only in an illustrated form by the manufacturers. The exhaustive routine of the medical physicists in the clinic do not make possible the accomplishment of procedures for the confirmation of these parameters. This work presents the development of a methodology for the dosimetry of {sup 90}Sr+{sup 90}Y betatherapy applicators. The Monte Carlo code MCNP5 was used for the simulation of the percentage depth dose curves and dose distribution profiles produced by these applicators. The experimental measurements of the radial and axial radiation attenuation, have been done with a mini-extrapolation chamber, thermoluminescent dosimeters and radiographic films. The experimental results have been compared with the simulated values. Both percentage depth dose curves and the radial dose profiles, the theoretical and the experimental ones, have presented good agreement, which may validate the use of the MCNP5 for these simulations, confirming the viability of the usage of this method in procedures of beta emitter sources dosimetry. (author)

  20. Verification system development a dosimetric tridimensional using Solution Fricke gel in the application for verification of radiation therapy in arc modulated volumetric (VMAT) in treatment with target moving for breathing

    International Nuclear Information System (INIS)

    Sakuraba, Roberto Kenji

    2015-01-01

    Volumetric Modulated Arc Therapy (VMAT) is one of the methods most commonly used in teletherapy to treat cancer. The various technological advances and the evolution of treatment techniques made the VMAT as one of the state of the art methods for the treatment of some cancers. Part of this improvement is credited to improvements in accuracy and prescription dose absorbed recommended to the patient over the years. This advance allows currently is possible to perform dosimetric calculations by means of the computerized planning system, considering the heterogeneity of patients, such as tissues and organs with different water compositions medium (reference radiation), and individual patient contour the movement of tumors breathing. Such advances require quality control of these tools, in order to ensure that the entire treatment process is satisfactory and accurate. Up to now, the community lacks an experimental system capable of evaluating, considering the uncertainty levels if the computerized planning systems are able to consider the movement of targets in the treatments with VMAT. In this paper, will be presented the results obtained with the phantom Fricke Xylenol Gel, capable of measuring the differences introduced by movement using the Magnetic Resonance Image - MRI and compared qualitatively and quantitatively. The main stages of the phantom development, their experimental results, conclusions and comparisons with other systems are discussed. (author)

  1. United States Air Force Company Grade Officer PME and Leader Development: Establishing a Glide Path for Future Success

    National Research Council Canada - National Science Library

    Owens, Patrick

    2002-01-01

    .... This monograph addresses the role of PME at the company grade level in the development of Air Force officers in light of ongoing Army and Air Force leader development initiatives as well as recent...

  2. Development of an API 5L X-70 grade steel for sour gas resistance pipeline application

    Science.gov (United States)

    Mendoza, R.; Huante, J.; Camacho, V.; Alvarez-Fregoso, O.; Juarez-Islas, J. A.

    1999-10-01

    An API 5L X-70 grade steel for large diameter pipeline application with sour gas resistance was developed by electric arc furnace processing, furnace ladle treatment, vacuum degassing, ladle treatment, and continuous casting, followed by three different controlled rolling schedules and air cooling or accelerated cooling. Mechanical properties equivalent to those of an API 5L X-70 grade steel were achieved in slabs with content ranges from 0.25 to 0.37 wt% C, 1.31 to 1.53 wt% Mn, 0.082 to 0.095 wt% Nb, and 0.008 to 0.015 wt% Ti. The slabs were processed by using a controlled rolled and accelerated cooling schedule.

  3. Computational model for dosimetric purposes in dental procedures

    International Nuclear Information System (INIS)

    Kawamoto, Renato H.; Campos, Tarcisio R.

    2013-01-01

    This study aims to develop a computational model for dosimetric purposes the oral region, based on computational tools SISCODES and MCNP-5, to predict deterministic effects and minimize stochastic effects caused by ionizing radiation by radiodiagnosis. Based on a set of digital information provided by computed tomography, three-dimensional voxel model was created, and its tissues represented. The model was exported to the MCNP code. In association with SICODES, we used the Monte Carlo N-Particle Transport Code (MCNP-5) method to play the corresponding interaction of nuclear particles with human tissues statistical process. The study will serve as a source of data for dosimetric studies in the oral region, providing deterministic effect and minimize the stochastic effect of ionizing radiation

  4. Development of a personalized dosimetric tool for radiation protection in case of internal contamination and targeted radiotherapy in nuclear medicine; Developpement d'un outil dosimetrique personnalise pour la radioprotection en contamination interne et la radiotherapie vectorisee en medecine nucleaire

    Energy Technology Data Exchange (ETDEWEB)

    Chiavassa, S

    2005-12-15

    Current internal dosimetric estimations are based on the M.I.R.D. formalism and used standard mathematical models. These standard models are often far from a given patient morphology and do not allow to perform patient-specific dosimetry. The aim of this study was to develop a personalized dosimetric tool, which takes into account real patient morphology, composition and densities. This tool, called O.E.D.I.P.E., a French acronym of Tool for the Evaluation of Personalized Internal Dose, is a user-friendly graphical interface. O.E.D.I.P.E. allows to create voxel-based patient-specific geometries and associates them with the M.C.N.P.X. Monte Carlo code. Radionuclide distribution and absorbed dose calculation can be performed at the organ and voxel scale. O.E.D.I.P.E. can be used in nuclear medicine for targeted radiotherapy and in radiation protection in case of internal contamination. (author)

  5. The development of the common fraction concept in Grade Three learners

    Directory of Open Access Journals (Sweden)

    Claire Fraser

    2004-10-01

    Full Text Available This paper reports on a study undertaken on the development of the common fraction concept in Grade Three learners. According to the principles of a problem-centred approach to teaching and learning, learners were encouraged to discuss, reflect on and make sense of the mathematics they were doing while solving problems set in real-life contexts as vehicles for learning. The results indicate that learners are able to develop a stable common fraction concept and a deeper understanding of the concept.

  6. Development of Necessary Technology for localizing of Nuclear Safety Grade I and C System

    International Nuclear Information System (INIS)

    Kwon, Kee Choon; Jang, Tong Il; Kim, Jung Tack

    2010-08-01

    Through KNICS and Nu-Tech 2012, a MMIS(Man-Machine Interface System) package for nuclear plants was localized and is expected to be applied to SUN 1,2 plants. This study is aimed to support the application of the MMIS package including the following technologies that meet strengthened regulation requirements and enhanced utility's performance requirements to nuclear plants. - Dedication to safety-grade computers and real time operating systems - The broadband communication network for safety information - Application of the automatic test for safety systems - Application of programmable logic controllers to nuclear plants - Development strategy for an integrated SW development tool for control device

  7. Vocabulary development and intervention for English learners in the early grades.

    Science.gov (United States)

    Baker, Doris Luft; Al Otaiba, Stephanie; Ortiz, Miriam; Correa, Vivian; Cole, Ron

    2014-01-01

    The purpose of this chapter is to describe the vocabulary development and promising, evidence-based vocabulary interventions for English learners (ELs) from preschool through second grade. To achieve this purpose, we have taken six steps. First, we describe the elements of language development in the native language (L1) and a second language (L2) and how these elements relate to three phases of reading development (i.e., the prereading phase, the learning to read phase, and the reading to learn phase). We contend that in order for ELs to succeed in school, they need a strong language foundation prior to entering kindergarten. This language foundation needs to continue developing during the "learning to read" and "reading to learn" phases. Second, we describe the limitations of current practice in preschool for ELs related to vocabulary instruction and to family involvement to support children's language development. Third, we report curricular challenges faced by ELs in early elementary school, and we relate these challenges to the increase in reading and language demands outlined in the Common Core State Standards (CCSS). Specific language activities that can help meet some of the demands are provided in a table. Fourth, we synthesize the research on evidence-based vocabulary instruction and intervention and discuss implications for practice with ELs. Fifth, we describe two intervention projects under development that have the potential to improve EL vocabulary and language proficiency in the early grades. We conclude with a summary of the chapter and provide additional resources on the topic.

  8. An Investigation of Fifth Grade Students' Conceptual Development of Probability through Activity Based Instruction: A Quasi-Experimental Study

    Science.gov (United States)

    Gurbuz, Ramazan; Catlioglu, Hakan; Birgin, Osman; Erdem, Emrullah

    2010-01-01

    This study aims to compare the effects of activity-based instruction and traditional instruction on fifth grade primary school students' conceptual development of probability. The study was conducted through quasi-experimental method and carried out with 50 5th grade primary school students, 25 for experimental group and 25 for control group. The…

  9. The Effect of Using Computer Games in Teaching Mathematics on Developing the Number Sense of Fourth Grade Students

    Science.gov (United States)

    Nejem, Khamis Mousa; Muhanna, Wafa

    2013-01-01

    The purpose of this study was to investigate the effect of using computer games in teaching mathematics on developing the number sense of fourth grade students. To achieve this purpose a study sample of (81) students was selected from the fourth grade. This sample was divided into two groups. One group was randomly chosen to be the experimental…

  10. Restaurant Industry. Grade Three. One in a Series of Career Development Curriculum Units for the Elementary Classroom. (Third Edition).

    Science.gov (United States)

    Briggs, Gail; And Others

    Focusing on the occupational clusters of health, hospitality and recreation, this unit entitled "Restaurant Industry" is one of four grade 3 units which are part of a total set of twenty-seven career development curriculum units for grades K-6. This unit is organized into four sections. Section 1 identifies two career…

  11. Developing a Clinical-Grade Cryopreservation Protocol for Human Testicular Tissue and Cells

    Science.gov (United States)

    Pacchiarotti, Jason; Ramos, Thomas; Howerton, Kyle; Greilach, Scott; Zaragoza, Karina; Olmstead, Marnie; Izadyar, Fariborz

    2013-01-01

    Recent work in preservation of female fertility as well as new information on the nature of spermatogonial stem cells has prompted an investigation into the possibility of an effective clinical-grade procedure for the cryopreservation of testicular cells and/or tissue. Clinical-grade reagents, validated equipment, and protocols consistent with cGTP/cGMP standards were used in developing a procedure suitable for the safe and effective cryopreservation of human testicular cells and tissues. These procedures were designed to be compliant with the relevant FDA regulations. The procedure proved to effectively cryopreserve both testicular cells and tissue. The cryopreservation of testicular tissue was comparable in most aspects we measured to the cryopreservation of isolated cells, except that the viability of the cells from cryopreserved testicular tissue was found to be significantly higher. On the other hand, cryopreservation of cells is preferred for cell analysis, quality control, and sterility testing. This study demonstrates that testicular tissue and cells from sexual reassignment patients can be successfully cryopreserved with a clinical-grade procedure and important cell populations are not only preserved but also enriched by the process. Further studies will determine whether these findings from hormone-treated patients can be generalized to other patients. PMID:23509810

  12. The influence of morphological awareness on the literacy development of first-grade children.

    Science.gov (United States)

    Wolter, Julie A; Wood, Alexis; D'zatko, Kim W

    2009-07-01

    The purpose of this study was twofold. First, we investigated whether first-grade children evidenced morphological awareness and whether they used their knowledge of morphological relations to guide their spelling. Second, we sought to determine whether children's morphological awareness abilities were predictive of their performance on word-level reading and spelling measures. At the beginning of the academic school year, 43 first-grade children were administered an oral morphological awareness production task, a series of single-word morphological spelling tasks, and a battery of language and literacy tasks. The first-grade children were able to generate words reflecting morphological relations before they received explicit instruction regarding morphological relations between words. In addition, the children used morphological information to guide their spelling of single words, as evidenced by a difference in patterns of spellings between 1- and 2-morpheme words. Regression analyses revealed that the children's performance on the oral morphological production task explained unique variance on their reading and spelling measures above and beyond the variance that was accounted for by phonological awareness. Children as young as first graders evidenced morphological awareness, and morphological awareness influenced the children's literacy development. Theoretical implications of the findings are discussed.

  13. BAPTA-AM dramatically improves maturation and development of bovine oocytes from grade-3 cumulus-oocyte complexes.

    Science.gov (United States)

    Hu, Hongmei; Mo, Xianhong; Li, Xue; Fu, Xiangwei; Hou, Yunpeng

    2018-01-01

    Intracellular free calcium ([Ca 2+ ] i ) is essential for oocyte maturation and early embryonic development. Here, we investigated the role of [Ca 2+ ] i in oocytes from cumulus-oocyte complexes (COCs) with respect to maturation and early embryonic development, using the calcium-buffering agent BAPTA-AM (1,2-bis[2-aminophenoxy]ethane-N,N,N',N'-tetraacetic acid tetrakis [acetoxymethyl ester]). COCs were graded based on compactness of the cumulus mass and appearance of the cytoplasm, with Grade 1 indicating higher quality and developmental potential than Grade 3. Results showed that: (i) [Ca 2+ ] i in metaphase-II (MII) oocytes from Grade-3 COCs was significantly higher than those from Grade-1 COCs, and was significantly reduced by BAPTA-AM; (ii) nuclear maturation of oocytes from Grade-3 COCs treated with BAPTA-AM was enhanced compared to untreated COCs; (iii) protein abundance of Cyclin B and oocyte-specific Histone 1 (H1FOO) was improved in MII oocytes from Grade-3 COCs treated with BAPTA-AM; (iv) Ca 2+ transients were triggered in each group upon fertilization, and the amplitude of [Ca 2+ ] i oscillations increased in the Grade-3 group upon treatment with BAPTA-AM, with the magnitude approaching that of the Grade-1 group; and (v) cleavage rates and blastocyst-formation rates were improved in the Grade-3 group treated with BAPTA-AM compared to untreated controls following in vitro fertilization and parthenogenetic activation. Therefore, BAPTA-AM dramatically improved oocyte maturation, oocyte quality, and embryonic development of oocytes from Grade-3 COCs. © 2017 Wiley Periodicals, Inc.

  14. Development of a framework for resilience measurement: Suggestion of fuzzy Resilience Grade (RG) and fuzzy Resilience Early Warning Grade (REWG).

    Science.gov (United States)

    Omidvar, Mohsen; Mazloumi, Adel; Mohammad Fam, Iraj; Nirumand, Fereshteh

    2017-01-01

    Resilience engineering (RE) can be an alternative technique to the traditional risk assessment and management techniques, to predict and manage safety conditions of modern socio-technical organizations. While traditional risk management approaches are retrospective and highlight error calculation and computation of malfunction possibilities, resilience engineering seeks ways to improve capacity at all levels of organizations in order to build strong yet flexible processes. Considering the resilience potential measurement as a concern in complex working systems, the aim of this study was to quantify the resilience by the help of fuzzy sets and Multi-Criteria Decision-Making (MCDM) techniques. In this paper, we adopted the fuzzy analytic hierarchy process (FAHP) method to measure resilience in a gas refinery plant. A resilience assessment framework containing six indicators, each with its own sub-indicators, was constructed. Then, the fuzzy weights of the indicators and the sub-indicators were derived from pair-wise comparisons conducted by experts. The fuzzy evaluating vectors of the indicators and the sub-indicators computed according to the initial assessment data. Finally, the Comprehensive Resilience Index (CoRI), Resilience Grade (RG), and Resilience Early Warning Grade (REWG) were established. To demonstrate the applicability of the proposed method, an illustrative example in a gas refinery complex (an instance of socio-technical systems) was provided. CoRI of the refinery ranked as "III". In addition, for the six main indicators, RG and REWG ranked as "III" and "NEWZ", respectively, except for C3, in which RG ranked as "II", and REWG ranked as "OEWZ". The results revealed the engineering practicability and usefulness of the proposed method in resilience evaluation of socio-technical systems.

  15. Improving 6th Grade Climate Literacy using New Media (CLINM) and Teacher Professional Development

    Science.gov (United States)

    Smith, G.; Schmidt, C.; Metzger, E. P.; Cordero, E. C.

    2012-12-01

    The NASA-funded project, Improving 6th Grade Climate Literacy using New Media (CLINM), is designed to improve the climate literacy of California's 450,000 6th-grade students through teacher professional development that presents climate change as an engaging context for teaching earth science standards. The project fosters experience-based interaction among learners and encourages expressive creativity and idea-exchange via the web and social media. The heart of the CLINM project is the development of an online educator-friendly experience that provides content expert-reviewed, teacher-tested, standards-based educational resources, classroom activities and lessons that make meaningful connections to NASA data and images as well as new media tools (videos, web, and phone applications) based on the Green Ninja, a climate-action superhero who fights global warming by inspiring personal action (www.greenninja.info). In this session, we will discuss this approach to professional development and share a collection of teacher-tested CLINM resources. CLINM resources are grounded in earth system science; classroom activities and lessons engage students in exploration of connections between natural systems and human systems with a particular focus on how climate change relates to everyone's need for food, water, and energy. CLINM uses a team-based approach to resource development, and partners faculty in San José State University's (SJSU) colleges of Science, Education, and Humanities and the Arts with 6th-grade teachers from local school districts, a scientist from NASA Ames Research Center and climate change education projects at Stanford University, the University of Nebraska at Lincoln, and the University of Idaho. Climate scientists and other content experts identify relevant concepts and work with science educators to develop and/or refine classroom activities to elucidate those concepts; activities are piloted in pre-service science methods courses at SJSU and in

  16. Dosimetric studies in diagnostic radiology

    International Nuclear Information System (INIS)

    Mohamadain, K. E. M.

    2004-04-01

    A dosimetric study in pediatric radiology and adult patients was currently being carried out at the pediatrics units of two large hospitals in Rio de Janeiro city: IPPMG (Instituto de Pediatric e Puericultura Martagao Gesteira, University hospital of federal University of Rio de Janeiro), IFF (Instituto Fernandes Figueira, FIOCRUZ) and Hospital Geral de Bonsucesso, a large public hospital in Rio de Janeiro city (HGB) Brazil. The dosimetric study was also performed at three pediatrics units in Sudan, namely, Ahmed Gasim, Khartoum and Omdurman hospitals. For chest x-ray examination the entrance skin dose(ESD) for AP, PA and LAT projections of pediatric patients, and the scattered dose at the thyroid, ovary and gonads have been obtained with thermoluminescent dosimeters (TLD) and with use of a software package Dosecal in thr Brazilian hospitals, and with the software dosecal in the Sudanese hospitals.The aim of this work was to estimate the entrance skin dose (ESD), the effective dose (ED) and the body organ dose (BOD) for chest x-ray exposure in pediatric patients, and different exams for adults patients, and to compare the results obtained in the tow Countries Sudan and Brazil with the reference dose level. For ESD evaluation of the chest x-ray, three different TL dosimeters have been used, namely LiF: Mg, Ti (TLD 100) CaSo 4 : Dy and LiF:Mg, Cu,P (TLD 100 H). The age intervals considered were: 0-1 years, 1-5 years, 5-10 years and 10-15 years. The results obtained with all dosimeters were in good agreement with, those obtained by the dosecal software, especially for AP and PA projection. However, some discrepancies were found for the LAT projection. The results within Brazil were some what consistent while in Sudan, large difference were observed, it was also noted that the doses in Brazil hospitals were less than the reference dose levels while in Sudanese hospitals the doses were higher than the reference dose levels. For adult patients only the software dosecal

  17. Developing Elementary Science PCK for Teacher Education: Lessons Learned from a Second Grade Partnership

    Science.gov (United States)

    Bradbury, Leslie U.; Wilson, Rachel E.; Brookshire, Laura E.

    2017-06-01

    In this self-study, two science educators partnered with two elementary teachers to plan, implement, and reflect on a unit taught in second grade classrooms that integrated science and language arts. The researchers hoped to increase their pedagogical content knowledge (PCK) for elementary science teaching so that they might use their experiences working in an elementary context to modify their practices in their elementary science method instruction. The research question guiding the study was: What aspects of our PCK for elementary science teaching do we as science educators develop by co-planning, co-teaching, and reflecting with second grade teachers? Data include transcripts of planning meetings, oral reflections about the experience, and videos of the unit being enacted. Findings indicate that managing resources for science teaching, organizing students for science learning, and reflecting on science teaching were themes prevalent in the data. These themes were linked to the model of PCK developed by Park and Oliver (Research in Science Education, 38, 261-284, 2008) and demonstrate that we developed PCK for elementary science teaching in several areas. In our discussion, we include several proposed changes for our elementary science methods course based on the outcomes of the study.

  18. Dosimetric approaches: pregnancy and lactation

    International Nuclear Information System (INIS)

    Rojo, Ana M.

    2001-01-01

    The female nuclear medicine patient is of special concern to the evaluation of radiation dose since radiation protection point of view: a)- The females overall body size and organ sizes are generally smaller than those of her male counterpart (thus her radiation doses will be higher, given the same amounts of administered activity and similar biokinetics), the effective doses could be 25 per cent higher than a man; b)- Female gonads are inside the body instead of outside and are near several organs often important as source organs in internal dosimetry; female gonads doses could be up to 10 or 30 higher than male gonads (usually 3 order); c)- Risk of breast cancer is significantly higher among females than males; d)- During the pregnancy due to placental transfer of radiopharmaceuticals or radiation exposure from the urinary bladder the embryo/fetus could receive doses that must be avoid; e)- In the case of nursing infant is of special concern in such an analysis to determine the interruption period to avoid doses in the nursing infant. The dosimetric approaches to take account to assess internal doses in the pregnant woman and during the breast feeding are discussed. (author)

  19. The role of the Secondary Laboratory of Dosimetric calibration in the implementation of the dosimetric magnitudes with radiological protection aims

    International Nuclear Information System (INIS)

    Perez Medina O, V.; Alvarez R, J.T.; Tovar M, V.M.

    2006-01-01

    It is very well-known the paper of the net of secondary laboratories of dosimetric calibration of the OAS in the dissemination of the traceability of the dosimetric magnitudes: kerma in air and absorbed dose in water, to the radiotherapy departments, given the high accuracy and precision that require the radiotherapy treatments. However the LSCD has other important areas at least for the development, implementation and evaluation of dosimetric magnitudes denominated operative magnitudes with ends of radiological protection: environmental equivalent dose H*(10), directional equivalent dose H'(0.07) and personal equivalent dose Hp. In the case of radiological protection the LSCD-ININ has been implementing the infrastructure to give service of personal dosimetry for photons and beta particles in terms of the operative magnitudes. For photons: X and gamma rays, it account with a secondary pattern camera PTW T34035 gauged in H * and Hp in the primary laboratory of Germany PTB. For the case of beta radiation its account with an extrapolation camera PTW 23392 with a secondary pattern kit of sources of the type I, gauged in terms of H'(0.07) in the PTB. (Author)

  20. Development of Application Programming Tool for Safety Grade PLC (POSAFE-Q)

    Energy Technology Data Exchange (ETDEWEB)

    Koo, Kyungmo; You, Byungyong; Kim, Tae-Wook; Cho, Sengjae; Lee, Jin S. [Pohang University of Science and Technology, Pohang (Korea, Republic of)

    2006-07-01

    The pSET (POSAFE-Q Software Engineering Tool) is an application programming tool of the POSAFE-Q which is a safety graded programmable logic controller (PLC) developed for the reactor protect system of the nuclear power plant. The pSET provides an integrated development environment (IDE) which includes editors, compiler, simulator, down loader, debugger, and monitor. The pSET supports the IEC61131-3 standard software model and languages such as LD (ladder diagram) and FBD (function block diagram) which are two of the most widely used PLC programming languages in industry fields. The pSET will also support SFC (sequential function chart) language. The pSET is developed as a part of a Korea Nuclear Instrumentation and Control System (KNICS) project.

  1. Development of Application Programming Tool for Safety Grade PLC (POSAFE-Q)

    International Nuclear Information System (INIS)

    Koo, Kyungmo; You, Byungyong; Kim, Tae-Wook; Cho, Sengjae; Lee, Jin S.

    2006-01-01

    The pSET (POSAFE-Q Software Engineering Tool) is an application programming tool of the POSAFE-Q which is a safety graded programmable logic controller (PLC) developed for the reactor protect system of the nuclear power plant. The pSET provides an integrated development environment (IDE) which includes editors, compiler, simulator, down loader, debugger, and monitor. The pSET supports the IEC61131-3 standard software model and languages such as LD (ladder diagram) and FBD (function block diagram) which are two of the most widely used PLC programming languages in industry fields. The pSET will also support SFC (sequential function chart) language. The pSET is developed as a part of a Korea Nuclear Instrumentation and Control System (KNICS) project

  2. Development of a dosimetric system for dental X-ray equipment quality control; Desenvolvimento de um sistema dosimetrico para controle de qualidade de equipamentos de raios-X odontologicos

    Energy Technology Data Exchange (ETDEWEB)

    Melo, Francisco Almeida de

    2002-08-01

    An electronic instrument with digital readout was designed and constructed to provide fast, simple and non-invasive measurements of X-ray dental equipment parameters. This instrument is capable of evaluating the entrance dose, exposure time, tube voltage (kVp) and beam filtration. It consists of a set of five photodiodes connected each one in the photocurrent mode to the input of a designed integrating electrometer. Three of the detectors are fixed under aluminium filters with different thicknesses, one is fixed under a 0.3 mm copper filter and the other has no filtration. The readings of the three detectors under aluminium filters and of the bare detector permit the determination of the half-value layer, which is used to calculate the beam filtration. The ratio between the readings of the detector below the copper filter and the one without filtration is used to determine the tube voltage. The signal produced by the detector without filter is used to evaluate the patient entrance dose, and to active an electronic timer for measuring the real exposure time. The tests and calibration of the instrument in different voltages in the 59 - 70kVp range, showed that its response is both stable and reproducible to within 1%. The instrument response was compared to the one from a commercial non-invasive X-ray test equipment (Gammex RMI Multifunction kVp meter). The results showed that the response of the developed instrument is in good agreement with the RMI meter which is the standard equipment for such measurements. These results indicate that the dosimetric system is suitable for use in Dental Quality Assurance Programs. (author)

  3. Chilean Nuclear Energy Commission dosimetric information system

    International Nuclear Information System (INIS)

    Guerrero Vallejos, Patricia Andrea

    1997-01-01

    This thesis discusses the nuclear radiation that people who work with radioactive material is exposed to and its control by the Chilean Nuclear Energy Commission. A full analysis of the System is presented with information about the Commission and the Department of Nuclear and Radiological Safety which runs the System. Ana analysis of the System is presented in order to obtain requirements. Management flow diagrams, the processes involved and current problems experienced by the users are described. A design logic is modeled producing Data Flow Diagrams (DFD). based on this physical design, or, Model of Physical Data, is prepared including tables, attributes, types of data, primary and foreign keys. A description is presented of how the System is implemented, the tools that are used and how the testing phase is carried out. The Dosimetry System meets the criteria for a Software Engineering project, where the basic cycle was used as a working methodology. The System developed supports the dosimetric control of people exposed to radioactive material. (author)

  4. Brachial Plexopathy in Apical Non-Small Cell Lung Cancer Treated With Definitive Radiation: Dosimetric Analysis and Clinical Implications

    Energy Technology Data Exchange (ETDEWEB)

    Eblan, Michael J.; Corradetti, Michael N.; Lukens, J. Nicholas; Xanthopoulos, Eric [Department of Radiation Oncology, Abramson Cancer Center, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania (United States); Mitra, Nandita [Department of Biostatistics and Epidemiology, Abramson Cancer Center, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania (United States); Christodouleas, John P.; Grover, Surbhi; Fernandes, Annemarie T. [Department of Radiation Oncology, Abramson Cancer Center, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania (United States); Langer, Corey J.; Evans, Tracey L.; Stevenson, James [Department of Medical Oncology, Abramson Cancer Center, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania (United States); Rengan, Ramesh [Department of Radiation Oncology, Abramson Cancer Center, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania (United States); Apisarnthanarax, Smith, E-mail: apisarns@uphs.upenn.edu [Department of Radiation Oncology, Abramson Cancer Center, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania (United States)

    2013-01-01

    Purpose: Data are limited on the clinical significance of brachial plexopathy in patients with apical non-small cell lung cancers (NSCLC) treated with definitive radiation therapy. We report the rates of radiation-induced brachial plexopathy (RIBP) and tumor-related brachial plexopathy (TRBP) and associated dosimetric parameters in apical NSCLC patients. Methods and Materials: Charts of NSCLC patients with primary upper lobe or superiorly located nodal disease who received {>=}50 Gy of definitive conventionally fractionated radiation or chemoradiation were retrospectively reviewed for evidence of brachial plexopathy and categorized as RIBP, TRBP, or trauma-related. Dosimetric data were gathered on ipsilateral brachial plexuses (IBP) contoured according to Radiation Therapy Oncology Group atlas guidelines. Results: Eighty patients were identified with a median follow-up and survival time of 17.2 and 17.7 months, respectively. The median prescribed dose was 66.6 Gy (range, 50.4-84.0), and 71% of patients received concurrent chemotherapy. RIBP occurred in 5 patients with an estimated 3-year rate of 12% when accounting for competing risk of death. Seven patients developed TRBP (estimated 3-year rate of 13%), comprising 24% of patients who developed locoregional failures. Grade 3 brachial plexopathy was more common in patients who experienced TRBP than RIBP (57% vs 20%). No patient who received {<=}78 Gy to the IBP developed RIBP. On multivariable competing risk analysis, IBP V76 receiving {>=}1 cc, and primary tumor failure had the highest hazard ratios for developing RIBP and TRBP, respectively. Conclusions: RIBP is a relatively uncommon complication in patients with apical NSCLC tumors receiving definitive doses of radiation, while patients who develop primary tumor failures are at high risk for developing morbid TRBP. These findings suggest that the importance of primary tumor control with adequate doses of radiation outweigh the risk of RIBP in this population of

  5. Brachial Plexopathy in Apical Non-Small Cell Lung Cancer Treated With Definitive Radiation: Dosimetric Analysis and Clinical Implications

    International Nuclear Information System (INIS)

    Eblan, Michael J.; Corradetti, Michael N.; Lukens, J. Nicholas; Xanthopoulos, Eric; Mitra, Nandita; Christodouleas, John P.; Grover, Surbhi; Fernandes, Annemarie T.; Langer, Corey J.; Evans, Tracey L.; Stevenson, James; Rengan, Ramesh; Apisarnthanarax, Smith

    2013-01-01

    Purpose: Data are limited on the clinical significance of brachial plexopathy in patients with apical non-small cell lung cancers (NSCLC) treated with definitive radiation therapy. We report the rates of radiation-induced brachial plexopathy (RIBP) and tumor-related brachial plexopathy (TRBP) and associated dosimetric parameters in apical NSCLC patients. Methods and Materials: Charts of NSCLC patients with primary upper lobe or superiorly located nodal disease who received ≥50 Gy of definitive conventionally fractionated radiation or chemoradiation were retrospectively reviewed for evidence of brachial plexopathy and categorized as RIBP, TRBP, or trauma-related. Dosimetric data were gathered on ipsilateral brachial plexuses (IBP) contoured according to Radiation Therapy Oncology Group atlas guidelines. Results: Eighty patients were identified with a median follow-up and survival time of 17.2 and 17.7 months, respectively. The median prescribed dose was 66.6 Gy (range, 50.4-84.0), and 71% of patients received concurrent chemotherapy. RIBP occurred in 5 patients with an estimated 3-year rate of 12% when accounting for competing risk of death. Seven patients developed TRBP (estimated 3-year rate of 13%), comprising 24% of patients who developed locoregional failures. Grade 3 brachial plexopathy was more common in patients who experienced TRBP than RIBP (57% vs 20%). No patient who received ≤78 Gy to the IBP developed RIBP. On multivariable competing risk analysis, IBP V76 receiving ≥1 cc, and primary tumor failure had the highest hazard ratios for developing RIBP and TRBP, respectively. Conclusions: RIBP is a relatively uncommon complication in patients with apical NSCLC tumors receiving definitive doses of radiation, while patients who develop primary tumor failures are at high risk for developing morbid TRBP. These findings suggest that the importance of primary tumor control with adequate doses of radiation outweigh the risk of RIBP in this population of

  6. Effects of Engineering Design-Based Science on Elementary School Science Students' Engineering Identity Development across Gender and Grade

    Science.gov (United States)

    Capobianco, Brenda M.; Yu, Ji H.; French, Brian F.

    2015-04-01

    The integration of engineering concepts and practices into elementary science education has become an emerging concern for science educators and practitioners, alike. Moreover, how children, specifically preadolescents (grades 1-5), engage in engineering design-based learning activities may help science educators and researchers learn more about children's earliest identification with engineering. The purpose of this study was to examine the extent to which engineering identity differed among preadolescents across gender and grade, when exposing students to engineering design-based science learning activities. Five hundred fifty preadolescent participants completed the Engineering Identity Development Scale (EIDS), a recently developed measure with validity evidence that characterizes children's conceptions of engineering and potential career aspirations. Data analyses of variance among four factors (i.e., gender, grade, and group) indicated that elementary school students who engaged in the engineering design-based science learning activities demonstrated greater improvements on the EIDS subscales compared to those in the comparison group. Specifically, students in the lower grade levels showed substantial increases, while students in the higher grade levels showed decreases. Girls, regardless of grade level and participation in the engineering learning activities, showed higher scores in the academic subscale compared to boys. These findings suggest that the integration of engineering practices in the science classroom as early as grade one shows potential in fostering and sustaining student interest, participation, and self-concept in engineering and science.

  7. Developing a model for problem-solving in a Grade 4 mathematics classroom

    Directory of Open Access Journals (Sweden)

    Susan Nieuwoudt

    2015-11-01

    Full Text Available The teaching of problem-solving through the development of a problem-solving model was investigated in a Grade 4 mathematics classroom. Learners completed a questionnaire regarding their knowledge of mathematical problem-solving, their attitudes towards problem-solving, as well as their experiences in solving problems. Learners’ responses revealed overall negative beliefs towards problem-solving as well as a lack of knowledge about what problem-solving in mathematics entails. The teacher then involved the learners in a structured learning programme where they worked in cooperative groups of six on different kinds of mathematical problems to solve. The groups regularly engaged in discussions about the different strategies they were using to solve a specific problem and eventually succeeded in formulating a generic problem-solving model they could call their own. The model was effectively used by the learners to solve various mathematical problems, reflecting their levels of cognitive development to a certain extent.

  8. Analysis of clinical and dosimetric factors associated with severe acute radiation pneumonitis in patients with locally advanced non-small cell lung cancer treated with concurrent chemotherapy and intensity-modulated radiotherapy.

    Science.gov (United States)

    Shi, Anhui; Zhu, Guangying; Wu, Hao; Yu, Rong; Li, Fuhai; Xu, Bo

    2010-05-12

    To evaluate the association between the clinical, dosimetric factors and severe acute radiation pneumonitis (SARP) in patients with locally advanced non-small cell lung cancer (LANSCLC) treated with concurrent chemotherapy and intensity-modulated radiotherapy (IMRT). We analyzed 94 LANSCLC patients treated with concurrent chemotherapy and IMRT between May 2005 and September 2006. SARP was defined as greater than or equal 3 side effects and graded according to Common Terminology Criteria for Adverse Events (CTCAE) version 3.0. The clinical and dosimetric factors were analyzed. Univariate and multivariate logistic regression analyses were performed to evaluate the relationship between clinical, dosimetric factors and SARP. Median follow-up was 10.5 months (range 6.5-24). Of 94 patients, 11 (11.7%) developed SARP. Univariate analyses showed that the normal tissue complication probability (NTCP), mean lung dose (MLD), relative volumes of lung receiving more than a threshold dose of 5-60 Gy at increments of 5 Gy (V5-V60), chronic obstructive pulmonary disease (COPD) and Forced Expiratory Volume in the first second (FEV1) were associated with SARP (p 4.2% and NTCP 50% were 5.7% and 29.2%, respectively (p < 0.01). NTCP value and V10 are the useful indicators for predicting SARP in NSCLC patients treated with concurrent chemotherapy and IMRT.

  9. Preliminary dosimetric methodology for a new cobalt-60 irradiator for radioinduced necrosis

    Energy Technology Data Exchange (ETDEWEB)

    Moura, Eduardo S.; Mosca, Rodrigo C.; Zeituni, Carlos A.; Rostelato, Maria Elisa C.M.; Mathor, Monica B., E-mail: esmoura@ipen.b [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Sakuraba, Roberto K.; Goncalves, Vinicius D. [Hospital Israelita Albert Einstein (HIAE), Sao Paulo, SP (Brazil)

    2011-07-01

    The use of ionizing radiation in medical procedures, as radiotherapy, is a well-established clinical process and it has been used for several decades with good clinical results and continuous technology development for treatment optimization. On the contrary, some injuries such as necrosis, may occur with patients, due to wrong administration of the absorbed dose or with expected side effects. To evaluate how these injuries could be investigated and how they can be treated, a new Cobalto-60 irradiator was developed to induce radionecrosis in mice. This irradiator is composed by a cylindrical size and it was set up with eleven Cobalt-60 sources aligned in the surface of a cylindrical lead. This alignment guarantees a small dose focal area in a longitudinal table, with proper frames for positioning mice precisely during the irradiations period. The dosimetric procedure will measure the absorbed dose in the dose focal area, delimited the area of irradiation with penumbra regions (gradients absorbed dose profiles) and others anatomical regions of the mice with high radiosensitivity. Possible dosimetric procedures and related devices will be present in this work,. The obtained dosimetric data will be applied to ensure the accurate period of radiation of a given position. This preliminary study assures that the fundamental dosimetric process of this new Cobalt-60 irradiator and it predicates that dosimetric processes area feasible to be conducted. (author)

  10. Preliminary dosimetric methodology for a new cobalt-60 irradiator for radioinduced necrosis

    International Nuclear Information System (INIS)

    Moura, Eduardo S.; Mosca, Rodrigo C.; Zeituni, Carlos A.; Rostelato, Maria Elisa C.M.; Mathor, Monica B.; Sakuraba, Roberto K.; Goncalves, Vinicius D.

    2011-01-01

    The use of ionizing radiation in medical procedures, as radiotherapy, is a well-established clinical process and it has been used for several decades with good clinical results and continuous technology development for treatment optimization. On the contrary, some injuries such as necrosis, may occur with patients, due to wrong administration of the absorbed dose or with expected side effects. To evaluate how these injuries could be investigated and how they can be treated, a new Cobalto-60 irradiator was developed to induce radionecrosis in mice. This irradiator is composed by a cylindrical size and it was set up with eleven Cobalt-60 sources aligned in the surface of a cylindrical lead. This alignment guarantees a small dose focal area in a longitudinal table, with proper frames for positioning mice precisely during the irradiations period. The dosimetric procedure will measure the absorbed dose in the dose focal area, delimited the area of irradiation with penumbra regions (gradients absorbed dose profiles) and others anatomical regions of the mice with high radiosensitivity. Possible dosimetric procedures and related devices will be present in this work,. The obtained dosimetric data will be applied to ensure the accurate period of radiation of a given position. This preliminary study assures that the fundamental dosimetric process of this new Cobalt-60 irradiator and it predicates that dosimetric processes area feasible to be conducted. (author)

  11. Clinical and dosimetric analysis of peculiarities of intellectual development, mental and behavioural disorders in children with oncological pathology of the thyroid gland

    International Nuclear Information System (INIS)

    Igumnov, S.A.; Drozdovich, V.V.

    1998-01-01

    A study of 116 children with thyroid cancer was conducted in 1995-1997. On the basis of the data obtained the three-level system of prophylaxis and correction of mental and behavioural disorders in the children suffering from thyroid cancer has been developed

  12. Using the Grade Approach to Support the Development of Recommendations for Public Health Interventions in Radiation Emergencies

    International Nuclear Information System (INIS)

    Carr, Z.; Clarke, M.; Akl, E.A.; Schneider, R.; Murith, C.; Li, C.; Parrish-Sprowl, J.; Stenke, L.; Cui-Ping, L.; Bertrand, S.; Miller, C.

    2016-01-01

    The World Health Organization (WHO) guideline development policy requires that WHO guidelines be developed in a manner that is transparent and based on all available evidences, which must be synthesised and formally assessed for quality. To fulfil this requirement, the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach of rating quality of evidence and grading strength of recommendations was applied when developing the WHO recommendations on public health interventions in radiation emergencies. The guideline development group (GDG) formulated 10 PICO (P: population; I: intervention; C: comparator; O: outcomes) questions to guide the development of recommendations on response interventions during the early/intermediate and late emergency phases and on risk communications for mitigating psycho-social impact of radiation emergencies. For each PICO question, an extensive evidence search and systematic review was conducted. The GDG then formulated the recommendations using the evidence to recommendation (E-2-R) decision-making matrix and evaluated the strength of each recommendation. (authors)

  13. NOTE: The Virtual Family—development of surface-based anatomical models of two adults and two children for dosimetric simulations

    Science.gov (United States)

    Christ, Andreas; Kainz, Wolfgang; Hahn, Eckhart G.; Honegger, Katharina; Zefferer, Marcel; Neufeld, Esra; Rascher, Wolfgang; Janka, Rolf; Bautz, Werner; Chen, Ji; Kiefer, Berthold; Schmitt, Peter; Hollenbach, Hans-Peter; Shen, Jianxiang; Oberle, Michael; Szczerba, Dominik; Kam, Anthony; Guag, Joshua W.; Kuster, Niels

    2010-01-01

    The objective of this study was to develop anatomically correct whole body human models of an adult male (34 years old), an adult female (26 years old) and two children (an 11-year-old girl and a six-year-old boy) for the optimized evaluation of electromagnetic exposure. These four models are referred to as the Virtual Family. They are based on high resolution magnetic resonance (MR) images of healthy volunteers. More than 80 different tissue types were distinguished during the segmentation. To improve the accuracy and the effectiveness of the segmentation, a novel semi-automated tool was used to analyze and segment the data. All tissues and organs were reconstructed as three-dimensional (3D) unstructured triangulated surface objects, yielding high precision images of individual features of the body. This greatly enhances the meshing flexibility and the accuracy with respect to thin tissue layers and small organs in comparison with the traditional voxel-based representation of anatomical models. Conformal computational techniques were also applied. The techniques and tools developed in this study can be used to more effectively develop future models and further improve the accuracy of the models for various applications. For research purposes, the four models are provided for free to the scientific community.

  14. Development of the Concept of Energy Conservation using Simple Experiments for Grade 10 Students

    Science.gov (United States)

    Rachniyom, S.; Toedtanya, K.; Wuttiprom, S.

    2017-09-01

    The purpose of this research was to develop students’ concept of and retention rate in relation to energy conservation. Activities included simple and easy experiments that considered energy transformation from potential to kinetic energy. The participants were 30 purposively selected grade 10 students in the second semester of the 2016 academic year. The research tools consisted of learning lesson plans and a learning achievement test. Results showed that the experiments worked well and were appropriate as learning activities. The students’ achievement scores significantly increased at the statistical level of 05, the students’ retention rates were at a high level, and learning behaviour was at a good level. These simple experiments allowed students to learn to demonstrate to their peers and encouraged them to use familiar models to explain phenomena in daily life.

  15. Development and application of a dosimetric methodology of therapeutic X radiation beams using a tandem system; Desenvolvimento e aplicacao de metodologia dosimetrica de feixes terapeuticos de raios X com sistema tandem

    Energy Technology Data Exchange (ETDEWEB)

    Sartoris, Carla Eri

    2001-07-01

    In radiotherapy the use of orthovoltage X radiation beams is still recommended; to obtain satisfactory results, a periodic control is necessary to check the performance of the ionization chambers and the radiation beams characteristics. This control is performed by using standard dosimetric procedures, as for example the determination of half-value layers and the absorbed dose rates. A Tandem system was established in this work using a pair of ionization chambers (a thimble type and a superficial type) used for measures in a medical institution, in substitution to the routine conventional procedure of determination of half-value layers using absorbers. The results obtained show the application of this method in dosimetric procedures of orthovoltage beams (radiotherapy) as a complement for a quality control program. (author)

  16. Can dosimetric parameters predict acute hematologic toxicity in rectal cancer patients treated with intensity-modulated pelvic radiotherapy?

    International Nuclear Information System (INIS)

    Wan, Juefeng; Liu, Kaitai; Li, Kaixuan; Li, Guichao; Zhang, Zhen

    2015-01-01

    To identify dosimetric parameters associated with acute hematologic toxicity (HT) in rectal cancer patients undergoing concurrent chemotherapy and intensity-modulated pelvic radiotherapy. Ninety-three rectal cancer patients receiving concurrent capecitabine and pelvic intensity-modulated radiation therapy (IMRT) were analyzed. Pelvic bone marrow (PBM) was contoured for each patient and divided into three subsites: lumbosacral spine (LSS), ilium, and lower pelvis (LP). The volume of each site receiving 5–40 Gy (V 5, V10, V15, V20, V30, and V40, respectively) as well as patient baseline clinical characteristics was calculated. The endpoint for hematologic toxicity was grade ≥ 2 (HT2+) leukopenia, neutropenia, anemia or thrombocytopenia. Logistic regression was used to analyze correlation between dosimetric parameters and grade ≥ 2 hematologic toxicity. Twenty-four in ninety-three patients experienced grade ≥ 2 hematologic toxicity. Only the dosimetric parameter V40 of lumbosacral spine was correlated with grade ≥ 2 hematologic toxicity. Increased pelvic lumbosacral spine V40 (LSS-V40) was associated with an increased grade ≥ 2 hematologic toxicity (p = 0.041). Patients with LSS-V40 ≥ 60 % had higher rates of grade ≥ 2 hematologic toxicity than did patients with lumbosacral spine V40 < 60 % (38.3 %, 18/47 vs.13 %, 6/46, p =0.005). On univariate and multivariate logistic regression analysis, lumbosacral spine V40 and gender was also the variable associated with grade ≥ 2 hematologic toxicity. Female patients were observed more likely to have grade ≥ 2 hematologic toxicity than male ones (46.9 %, 15/32 vs 14.8 %, 9/61, p =0.001). Lumbosacral spine -V40 was associated with clinically significant grade ≥ 2 hematologic toxicity. Keeping the lumbosacral spine -V40 < 60 % was associated with a 13 % risk of grade ≥ 2 hematologic toxicity in rectal cancer patients undergoing concurrent chemoradiotherapy

  17. Can We Measure the Transition to Reading? General Outcome Measures and Early Literacy Development From Preschool to Early Elementary Grades

    Directory of Open Access Journals (Sweden)

    Scott McConnell

    2015-06-01

    Full Text Available This study evaluated the extent to which existing measures met standards for a continuous suite of general outcome measures (GOMs assessing children’s early literacy from preschool through early elementary school. The study assessed 316 children from age 3 years (2 years prekindergarten through Grade 2, with 8 to 10 measures of language, alphabetic principle, phonological awareness, and beginning reading. We evaluated measures at each grade group against six standards for GOMs extracted from earlier work. We found that one measure of oral language met five or six standards at all grade levels, and several measures of phonological awareness and alphabetic principle showed promise across all five grade levels. Results are discussed in relation to ongoing research and development of a flexible and seamless system to assess children’s academic progress across time for effective prevention and remediation, as well as theoretical and empirical analyses in early literacy, early reading, and GOMs.

  18. Internal dosimetric evaluation due to uranium aerosols

    International Nuclear Information System (INIS)

    Garcia Aguilar Juan; Delgado Avila Gustavo

    1991-01-01

    The present work has like object to carry out the internal dosimetric evaluation to the occupationally exposed personnel, due to the inhalation of aerosols of natural uranium and enriched in the pilot plant of nuclear fuel production of the National Institute of Nuclear Research

  19. ESR dosimetric properties of some biomineral materials

    Energy Technology Data Exchange (ETDEWEB)

    Hassan, Gamal M. [Department of Ionizing Radiation Metrology, National Institute for Standards (NIS), Tersa Street, El-Haram, El-Giza, P.O. Box 136 Giza, El-Giza (Egypt)]. E-mail: gamalhassan65@hotmail.com; Sharaf, M.A. [Department of Ionizing Radiation Metrology, National Institute for Standards (NIS), Tersa Street, El-Haram, El-Giza, P.O. Box 136 Giza, El-Giza (Egypt)

    2005-02-01

    Dosimetric properties of g-irradiated modern coral and bioactive glass (Bio-G) samples analyzed with electron spin resonance (ESR) have been separately reported (Hassan et al., 2004; Sharaf and Hassan, 2004) and compared with alanine. These are combined here to allow a three-way comparison between these materials.

  20. The First Cycle of Developing Teaching Materials for Fractions in Grade Five Using Realistic Mathematics Education

    Directory of Open Access Journals (Sweden)

    Hongki Julie

    2013-07-01

    Full Text Available There are 3 questions that will be answered in this study, namely (1what are the contexts that can be used to introduce the meaning ofmultiplication of two fractions and to find the result of multiplying two fractions, (2 how to use these contexts to help students construct the understanding of the meaning of multiplication of two fractions and find the result of multiplying two fractions, and (3 what is the impact of the teaching-learning process that has been designed by researchers on the process of students’ knowledge construction.Learning approach which was used in developing teaching materialsabout fractions is realistic mathematics approach. Lesson plan wascreated for fifth grade elementary school students. The type of research used is development research. According to Gravemeijer and Cobb (in Akker, Gravemeijer, McKeney, and Nieveen, 2006 there are three phases in development research, namely (1 preparation of the trial design, (2 the trial design, and (3 a retrospective analysis. This paper presents the results of the first cycle of three cycles that have been planned.

  1. Development of a Standardized Method for Contouring the Lumbosacral Plexus: A Preliminary Dosimetric Analysis of this Organ at Risk Among 15 Patients Treated With Intensity-Modulated Radiotherapy for Lower Gastrointestinal Cancers and the Incidence of Radiation-Induced Lumbosacral Plexopathy

    Energy Technology Data Exchange (ETDEWEB)

    Yi, Sun K., E-mail: sun.yi@ucdmc.ucdavis.edu [Department of Radiation Oncology, University of California, Davis Cancer Center, Sacramento, CA (United States); Mak, Walter [Department of Radiology, University of California, Davis Medical Center, Sacramento, CA (United States); Yang, Claus C.; Liu Tianxiao [Department of Radiation Oncology, University of Mississippi Medical Center, Jackson, MS (United States); Cui Jing; Chen, Allen M.; Purdy, James A.; Monjazeb, Arta M. [Department of Radiation Oncology, University of California, Davis Cancer Center, Sacramento, CA (United States); Do, Ly [Cancer Care Institute, San Jose, CA (United States)

    2012-10-01

    Purpose: To generate a reproducible step-wise guideline for the delineation of the lumbosacral plexus (LSP) on axial computed tomography (CT) planning images and to provide a preliminary dosimetric analysis on 15 representative patients with rectal or anal cancers treated with an intensity-modulated radiotherapy (IMRT) technique. Methods and Materials: A standardized method for contouring the LSP on axial CT images was devised. The LSP was referenced to identifiable anatomic structures from the L4-5 interspace to the level of the sciatic nerve. It was then contoured retrospectively on 15 patients treated with IMRT for rectal or anal cancer. No dose limitations were placed on this organ at risk during initial treatment planning. Dosimetric parameters were evaluated. The incidence of radiation-induced lumbosacral plexopathy (RILSP) was calculated. Results: Total prescribed dose to 95% of the planned target volume ranged from 50.4 to 59.4 Gy (median 54 Gy). The mean ({+-}standard deviation [SD]) LSP volume for the 15 patients was 100 {+-} 22 cm{sup 3} (range, 71-138 cm{sup 3}). The mean maximal dose to the LSP was 52.6 {+-} 3.9 Gy (range, 44.5-58.6 Gy). The mean irradiated volumes of the LSP were V40Gy = 58% {+-} 19%, V50Gy = 22% {+-} 23%, and V55Gy = 0.5% {+-} 0.9%. One patient (7%) was found to have developed RILSP at 13 months after treatment. Conclusions: The true incidence of RILSP in the literature is likely underreported and is not a toxicity commonly assessed by radiation oncologists. In our analysis the LSP commonly received doses approaching the prescribed target dose, and 1 patient developed RILSP. Identification of the LSP during IMRT planning may reduce RILSP. We have provided a reproducible method for delineation of the LSP on CT images and a preliminary dosimetric analysis for potential future dose constraints.

  2. A Longitudinal Investigation of Reading Development from Kindergarten to Grade Eight in a Spanish-Speaking Bilingual Population

    Science.gov (United States)

    Grimm, Ryan P.; Solari, Emily J.; Gerber, Michael M.

    2018-01-01

    This longitudinal study used latent growth curve modeling to investigate English literacy development in a sample of Spanish-speaking language minority students from third through eighth grade. This study also compared the sample's literacy development to the entire population of California students using state standardized test data. Second, this…

  3. Motivation: The Value of Developing Intrinsic Motivation in Elementary School Students in Grades Four through Six

    Science.gov (United States)

    Gerstner, Gary M.

    2017-01-01

    This study sought to fill the gap in the literature concerning intrinsic motivation in elementary students in Grades 4-6 by examining 155 elementary school students and in-depth interviews with three elementary grade teachers. This study used data collected from the self-report survey called the Children's Academic Intrinsic Motivation Inventory…

  4. Automated grading of wood-slabs. The development of a prototype system

    DEFF Research Database (Denmark)

    Ersbøll, Bjarne Kjær; Conradsen, Knut

    1992-01-01

    , etc. Based on the relative distribution of these detected defects on the surface of a given slab, the slab is further classified into 5 quality grades: prime, standard, flamy, extra flamy and rejects. As a result of this project, a prototype for the computer vision grading system has been built...

  5. Improvement in the dosimetric CaSO4: Dy obtention method

    International Nuclear Information System (INIS)

    Campos, L.L.; Frutuoso, P.H.; Souto, V.J.

    1989-08-01

    With the purpose of saving up in the dosimetric CaSO 4 : Dy production, a new method was developed to obtain single crystals. In this method the nitrogen flux used to carry the acid vapour was substituted by compressed air. It was compared all dosimetric properties of the crystals. There is no alteration in the glow curve. The sensitivity is the same in both cases and the lower detection limit is 3.8 x 10 -8 C.Kg -1 (150 μR) [pt

  6. Development of materials with dosimetric applications

    International Nuclear Information System (INIS)

    Mendoza A, D.; Perez H, R.; Gonzalez, P.R.; Estrada G, R.; Salas C, P.

    2003-01-01

    The thermoluminescence (Tl) is a property that have certain materials, of emitting light thermally stimulated, when they have been exposed to a field of ionizing radiation. In this work an analysis of the Tl response induced by the gamma radiation in the zircon, titania and hydroxyapatite is presented. First the influence of the presence of graphite in the Tl response of the zircon is analyzed, next the sensitivity of the titania thermally treated to different temperatures is analyzed. Finally the Tl response produced by the hydroxyapatite synthesized by two different processes is studied. (Author)

  7. Radioecological and dosimetric consequences of the Chernobyl accident in France

    International Nuclear Information System (INIS)

    Renaud, Ph.; Beaugelin, K.; Maubert, H.; Ledenvic, Ph.

    1997-11-01

    This study has as objective a survey of the radioecological and dosimetric consequences of the Chernobyl accident in France, as well as a prognosis for the years to come. It was requested by the Direction of Nuclear Installation Safety (DSIN) in relation to different organisms which effected measurements after this accident. It is based on the use of combined results of measurements and modelling by means of the code ASTRAL developed at IPSN. Various measurements obtained from five authorities and institutions, were made available, such as: activity of air and water, soil, processed food, agricultural and natural products. However, to achieve the survey still a modelling is needed. ASTRAL is a code for evaluating the ecological consequences of an accident. It allows establishing the correspondence between the soil Remnant Surface Activities (RSA, in Bq.m -2 ), the activity concentration of the agricultural production and the individual and collective doses resulting from external and internal exposures (due to inhalation and ingestion of contaminated nurture). The results of principal synthesis documents on the Chernobyl accident and its consequences were also used. The report is structured in nine sections, as follows: 1.Introduction; 2.Objective and methodology; 3.Characterization of radioactive depositions; 4;Remnant surface activities; 5.Contamination of agricultural products and foods; 6.Contamination of natural, semi-natural products and of drinking water; 7.Dosimetric evaluations; 8.Proposals for the environmental surveillance; 9.Conclusion. Finally, after ten years, one concludes that at present the dosimetric consequences of the Chernobyl accident in France were rather limited. For the period 1986-2046 the average individual effective dose estimated for the most struck zone is lower than 1500 μSv, which represents almost 1% of the average natural exposure for the same period. At present, the cesium 137 levels are at often inferior to those recorded before

  8. Dosimetric study in iodine-125 seeds for brachytherapy application

    International Nuclear Information System (INIS)

    Zeituni, Carlos Alberto

    2008-01-01

    The demand for iodine-125 seeds for use in brachytherapy treatments has experienced an increase along recent years in Brazil and all over the world. All iodine-125 seed must have its operational parameters measured and/or calculated every time changes in the production process are carried out. A complete dosimetric measurement is very expensive, and it is recommended that this procedure must be repeated at least once a year. Thus, this work developed a methodology for the entire dosimetric process. This methodology is based on the scarce information available in the literature, once almost all the methodology used in large industrial laboratories is commercial secret. The proposed methodology was tested using seeds of Amersham-Oncura-Ge Healthcare, which is the largest seed manufactory in the world. In this new methodology, an automatic reader was employed in order to reduce the time required in the selection process of the TLD-100 dosimeters used and a postprocessing of the obtained spectra was carried out. A total of 142 dosimeters were used and only 29 have been selected using the new methodology. Measurements were performed using slabs of Solid Water RW1 to simulate measuring in the 'water', using three different experimental apparatus and each measurement was repeated at least three times. The TLD-100 calibration was performed using a Dermopan II - Siemens. The measured values showed a good agreement with the ones available in the literature. Finally, these measured values were compared with calculated ones obtained by a semiempirical simulation program, showing a good agreement and, therefore, demonstrating the validity of the proposed methodology regarding dosimetric calculations. (author)

  9. Graded Approach to the Development of a Contingency Plan for On-Line Maintenance

    International Nuclear Information System (INIS)

    Chang, Hee Seung; Kim, Jung Wun; Song, Tae Young

    2012-01-01

    Many utilities perform preventive maintenance for safety systems during power operation to improve equipment reliability so as to focus on the work activities more easily and improve the quality of maintenance. Such a strategy can also reduce outage work activities, thus allowing resources to be utilized effectively. Preventive maintenance during power operation, known as on-line maintenance (OLM), requires an assessment and mitigation of risk, which can increase owing to out-of-service safety systems. One of the mitigation action plans is a contingency plan. EPRI recommends the development of a contingency plan for all planned system outages which include factors that strongly affect safety. The Korea Hydro and Nuclear Power Company (KHNP) undertook the preventive maintenance of the Essential Chilled Water System (ECWS) of a Westinghouse plant as a pilot OLM implementation. During the preparation of the work activities, a contingency plan was a pertinent issue during the discussions with regulators, especially regarding the scope and depth of the plan. This paper discusses the purpose of a contingency plan, including as examples some cases of US utilities, and proposes a graded approach to develop a contingency plan for OLM in consideration of the risks

  10. The First Cycle of Developing Teaching Materials for Fractions in Grade Five Using Realistic Mathematics Education

    Directory of Open Access Journals (Sweden)

    Hongki Julie

    2013-07-01

    Full Text Available There are three questions that will be answered in this study, namely (1 what are the contexts that can be used to introduce the meaning of multiplication of two fractions and to find the result of multiplying two fractions, (2 how to use these contexts to help students construct the understanding of the meaning of multiplication of two fractions and find the result of multiplying two fractions, and (3 what is the impact of the teaching-learning process that has been designed by researchers on the process of students' knowledge construction. Learning approach which was used in developing teaching materials about fractions is realistic mathematics approach. Lesson plan was created for fifth grade elementary school students. The type of research used is developmental research. According to Gravemeijer and Cobb (in Akker, Gravemeijer, McKeney, and Nieveen, 2006 there are three phases in development research, namely (1 preparation of the trial design, (2 the trial design, and (3 retrospective analysis. This paper presents the results of the first cycle of three cycles that have been planned.Key words: fractions, realistic mathematics education, design research. DOI: http://dx.doi.org/10.22342/jme.4.2.415.172-187

  11. Change in the level of strength and endurance development of 5-6 grades pupils under cheerleading exercises influence

    Directory of Open Access Journals (Sweden)

    Tetyana Bala

    2015-06-01

    Full Text Available Purpose: determine the degree of change in the level of strength and endurance development of 5-6 grades pupils under cheerleading exercises influence. Material and Methods: theoretical analysis and generalization of scientific and methodical literature, pedagogical testing, pedagogical experiment and mathematical statistics methods. Results: parameters of strength and endurance development level are presented with their degree of change under cheerleading exercises influence for 5-6 grades pupils of secondary school. Conclusions: cheerleading exercises usage has positive influence on demonstrated strength and endurance degree of secondary school children by all investigated parameters.

  12. Developing Worksheet (LKS) Base on Process Skills in Curriculum 2013 at Elementary School Grade IV,V,VI

    Science.gov (United States)

    Subhan, M.; Oktolita, N.; Kn, M.

    2018-04-01

    The Lacks of students' skills in the learning process is due to lacks of exercises in the form of LKS. In the curriculum of 2013, there is no LKS as a companion to improve the students' skills. In order to solve those problem, it is necessary to develop LKS based on process skills as a teaching material to improve students' process skills. The purpose of this study is to develop LKS Process Skills based elementary school grade IV, V, VI which is integrated by process skill. The development of LKS can be used to develop the thematic process skills of elementary school students grade IV, V, VI based on curriculum 2013. The expected long-term goal is to produce teaching materials LKS Process Skill based of Thematic learning that is able to develop the process skill of elementary school students grade IV, V, VI. This development research refers to the steps developed by Borg & Gall (1983). The development process is carried out through 10 stages: preliminary research and gathering information, planning, draft development, initial test (limited trial), first product revision, final trial (field trial), product operational revision, Desemination and implementation. The limited subject of the this research is the students of SDN in Dharmasraya grade IV, V, VI. The field trial subjects in the experimental class are the students of SDN Dharmasraya grade IV, V, VI who have implemented the curriculum 2013. The data are collected by using LKS validation sheets, process skill observation sheets, and Thematic learning test (pre-test And post-test). The result of LKS development on the validity score is 81.70 (very valid), on practical score is 83.94 (very practical), and on effectiveness score is 86.67 (very effective). In the trial step the use of LKS using One Group Pretest-Posttest Design research design. The purpose of this trial is to know the effectiveness level of LKS result of development for improving the process skill of students in grade IV, V, and VI of elementary

  13. Pulse dose-rate brachytherapy and treatment of uterine cervix cancer: impact of a 3D or a 2D dosimetric support

    International Nuclear Information System (INIS)

    Tournat, H.; Chilles, A.; Charra-Brunaud, C.; Peiffert, D.; Ahmad, F.; Metayer, Y.

    2007-01-01

    Purpose To evaluate two dosimetric supports used in pulse dose rate brachytherapy (P.D.R.): coverage of target volumes, dose to organs at risk, residual tumor after surgery, survival. Patients and methods Twenty patients treated for uterine cervix tumor first by brachytherapy P.D.R. had a dosimetric CT-scan after implantation. For 9 patients, the treatment was planned from standard radiographies and then reported on CT-scan images. For 11 patients, it was directly planned from CT-scan. Six weeks after, 18 patients underwent surgery. Results With a median follow-up of 22 months, 2 year actuarial survival was 89%. Six patients developed grade II urinary or gynecological complications (LENT SOMA scale). No residual tumor was found for 12 patients (7 with a 3D treatment and 5 a 2 D treatment). Ninety-five percent of C.T.V.H.R. received 53 Gy (2D treatment) or 63 Gy (3D treatment). Two cm 3 of bladder wall received 63 Gy (2D) or 74 Gy (3D) although 2 cm 3 of rectal wall received 37 Gy (2D) and 35 Gy (3D). Conclusion Using CT-scan made us improve the coverage of the uterine cervix but increase the dose received by the bladder, without increasing the rate of histological remission after surgery. We should be prudent before changing our practice. (authors)

  14. Automated grading of wood-slabs. The development of a prototype system

    DEFF Research Database (Denmark)

    Ersbøll, Bjarne Kjær; Conradsen, Knut

    1992-01-01

    This paper proposes a method for automatically grading small beechwood slabs. The method involves two classification steps: the first step detects defects based on local visual texture; the second step utilizes the relative distribution of defects to perform a final grading assessment. At a major...... Danish plant for manufacture of parquet boards, the quality grading (visual quality) has always been done manually. As it is expected to be both expensive and difficult to recruit sufficient numbers of personnel to do this type of job in the future, it is of great interest to automate the function...

  15. FY17 Status Report on the Initial Development of a Constitutive Model for Grade 91 Steel

    Energy Technology Data Exchange (ETDEWEB)

    Messner, M. C. [Argonne National Lab. (ANL), Argonne, IL (United States); Phan, V. -T. [Argonne National Lab. (ANL), Argonne, IL (United States); Sham, T. -L. [Argonne National Lab. (ANL), Argonne, IL (United States)

    2017-07-01

    Grade 91 is a candidate structural material for high temperature advanced reactor applications. Existing ASME Section III, Subsection HB, Subpart B simplified design rules based on elastic analysis are setup as conservative screening tools with the intent to supplement these screening rules with full inelastic analysis when required. The Code provides general guidelines for suitable inelastic models but does not provide constitutive model implementations. This report describes the development of an inelastic constitutive model for Gr. 91 steel aimed at fulfilling the ASME Code requirements and being included into a new Section III Code appendix, HBB-Z. A large database of over 300 experiments on Gr. 91 was collected and converted to a standard XML form. Five families of Gr. 91 material models were identified in the literature. Of these five, two are potentially suitable for use in the ASME code. These two models were implemented and evaluated against the experimental database. Both models have deficiencies so the report develops a framework for developing and calibrating an improved model. This required creating a new modeling method for representing changes in material rate sensitivity across the full ASME allowable temperature range for Gr. 91 structural components: room temperature to 650° C. On top of this framework for rate sensitivity the report describes calibrating a model for work hardening and softening in the material using genetic algorithm optimization. Future work will focus on improving this trial model by including tension/compression asymmetry observed in experiments and necessary to capture material ratcheting under zero mean stress and by improving the optimization and analysis framework.

  16. Development of a model and computer code to describe solar grade silicon production processes. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Gould, R K; Srivastava, R

    1979-12-01

    Models and computer codes which may be used to describe flow reactors in which high purity, solar grade silicon is produced via reduction of gaseous silicon halides are described. A prominent example of the type of process which may be studied using the codes developed in this program is the SiCl/sub 4//Na reactor currently being developed by the Westinghouse Electric Corp. During this program two large computer codes were developed. The first is the CHEMPART code, an axisymmetric, marching code which treats two-phase flows with models describing detailed gas-phase chemical kinetics, particle formation, and particle growth. This code, based on the AeroChem LAPP (Low Altitude Plume Program) code can be used to describe flow reactors in which reactants mix, react, and form a particulate phase. Detailed radial gas-phase composition, temperature, velocity, and particle size distribution profiles are computed. Also, depositon of heat, momentum, and mass (either particulate or vapor) on reactor walls is described. The second code is a modified version of the GENMIX boundary layer code which is used to compute rates of heat, momentum, and mass transfer to the reactor walls. This code lacks the detailed chemical kinetics and particle handling features of the CHEMPART code but has the virtue of running much more rapidly than CHEMPART, while treating the phenomena occurring in the boundary layer in more detail than can be afforded using CHEMPART. These two codes have been used in this program to predict particle formation characteristics and wall collection efficiencies for SiCl/sub 4//Na flow reactors. Results are described.

  17. Literacy development of English language learners: The outcomes of an intervention programme in grade R

    Directory of Open Access Journals (Sweden)

    Anna-Mari Olivier

    2010-12-01

    Full Text Available This study aims to contribute to the knowledge base on the status and development of emergent literacy skills of learners receiving formal education in their second or additional language. The focus is on young English language learners (ELLs, i.e. learners whose home language is not English but who have English as their language of teaching and learning. This article reports on a study that investigated ELLs’ emergent literacy skills prior to entering grade 1 and then evaluated the effectiveness of an evidence-based stimulation programme on early literacy skills in the South African context. Using a quasi-experimental design, ELLs’ emergent literacy skills were assessed with an adapted version of 8 of the subtests of the Emergent Literacy Assessment battery (Willenberg, 2004 and were compared to those of English first language (L1 and of ELL control groups, both before and after the 8-week purpose-designed programme. While learners showed significant improvement on 6 of the 8 subtests, the programme did not significantly improve ELLs’ skills in comparison to those of the control groups. Possible independent variables contributing to the dearth of intervention effect include socio-economic status, learners’ L1, and teacher- and classroom-specific characteristics, all of which were considered in this study. Clinical implications for speech-language therapists with regard to assessment, intervention, service delivery and outcome measures are highlighted.

  18. The Use of Retelling Stories Technique in Developing English Speaking Ability of Grade 9 Students

    Directory of Open Access Journals (Sweden)

    Sasitorn Praneetponkrang

    2014-10-01

    Full Text Available This article aims to advocate retelling stories technique for developing speaking ability of grade 9 students in Thailand. Morrow’s theory (1981 and other scholars in retelling stories technique are presented. This technique is integrated in the lesson plans following Morrow’s framework. Narrative text of short stories which refer to daily life and social including pictures have been used for each lesson plan.  Students are trained to work as a group using story’s mind map, illustrations, and role-playing activities in class. There are three main steps of teaching retelling stories: before retelling (alternative techniques, while retelling (students’ practice by using activities of brainstorming, role play, and discussion and retelling story. The lesson plans will be piloted with 15 9th graders. This preliminary study is expected to provide an example of useful techniques in improving speaking ability, thus, it is expected to be used in other foundation English courses for Thai students.

  19. Literacy development of English language learners: the outcomes of an intervention programme in grade R.

    Science.gov (United States)

    Olivier, Anna-Mari; Anthonissen, Christine; Southwood, Frenette

    2010-12-01

    This study aims to contribute to the knowledge base on the status and development of emergent literacy skills of learners receiving formal education in their second or additional language. The focus is on young English language learners (ELLs), i.e. learners whose home language is not English but who have English as their language of teaching and learning. This article reports on a study that investigated ELLs' emergent literacy skills prior to entering grade 1 and then evaluated the effectiveness of an evidence-based stimulation programme on early literacy skills in the South African context. Using a quasi-experimental design, ELLs' emergent literacy skills were assessed with an adapted version of 8 of the subtests of the Emergent Literacy Assessment battery (Willenberg, 2004) and were compared to those of English first language (L1) and of ELL control groups, both before and after the 8-week purpose-designed programme. While learners showed significant improvement on 6 of the 8 subtests, the programme did not significantly improve ELLs' skills in comparison to those of the control groups. Possible independent variables contributing to the dearth of intervention effect include socio-economic status, learners' L1, and teacher- and classroom-specific characteristics, all of which were considered in this study. Clinical implications for speech-language therapists with regard to assessment, intervention, service delivery and outcome measures are highlighted.

  20. The Relations between Early Working Memory Abilities and Later Developing Reading Skills: A Longitudinal Study from Kindergarten to Fifth Grade

    Science.gov (United States)

    Nevo, Einat; Bar-Kochva, Irit

    2015-01-01

    This study investigated the relations of early working-memory abilities (phonological and visual-spatial short-term memory [STM] and complex memory and episodic buffer memory) and later developing reading skills. Sixty Hebrew-speaking children were followed from kindergarten through Grade 5. Working memory was tested in kindergarten and reading in…

  1. The Developing on Awareness of Water Resources Management of Grade 6 Students in Namphong Sub-Basin

    Science.gov (United States)

    Seehamat, Lumyai; Sanrattana, Unchalee; Tungkasamit, Angkana

    2016-01-01

    Awareness of water resources management is expression behavior as receive, response, valuing, and organization. Water resources is an important for everyone in the world and the recently water resources are be risky as lack of water, waste water, and blooding. The development on awareness of water resources management for grade 6 students is very…

  2. A Monte Carlo dosimetric quality assurance system for dynamic intensity-modulated radiotherapy

    International Nuclear Information System (INIS)

    Takegawa, Hideki; Yamamoto, Tokihiro; Miyabe, Yuki; Teshima, Teruki; Kunugi, Tomoaki; Yano, Shinsuke; Mizowaki, Takashi; Nagata, Yasushi; Hiraoka, Masahiro

    2005-01-01

    We are developing a Monte Carlo (MC) dose calculation system, which can resolve dosimetric issues derived from multileaf collimator (MLC) design for routine dosimetric quality assurance (QA) of intensity-modulated radiotherapy (IMRT). The treatment head of the medical linear accelerator equipped with MLC was modeled using the EGS4 MC code. A graphical user interface (GUI) application was developed to implement MC dose computation in the CT-based patient model and compare the MC calculated results with those of a commercial radiotherapy treatment planning (RTP) system, Varian Eclipse. To reduce computation time, the EGS4 MC code has been parallelized on massive parallel processing (MPP) system using the message passing interface (MPI). The MC treatment head model and MLC model were validated by the measurement data sets of percentage depth dose (PDD) and off-center ratio (OCR) in the water phantom and the film measurements for the static and dynamic test patterns, respectively. In the treatment head model, the MC calculated results agreed with those of measurements for both of PDD and OCR. The MC could reproduce all of the MLC dosimetric effects. A quantitative comparison between the results of MC and Eclipse was successfully performed with the GUI application. Parallel speed-up became almost linear. An MC dosimetric QA system for dynamic IMRT has been developed, however there were large dose discrepancies between the MC and the measurement in the MLC model simulation, which are now being investigated. (author)

  3. Model dosimetric for Radon and Daughters

    International Nuclear Information System (INIS)

    Puerta, J.A.; Cardenas, H.F.

    1998-01-01

    You elaborates a model dosimetric for radon and their products of decline of short half life starting from the new model of the breathing tract of the publication 66 of the ICRP and the use of the systemic models proposed in the publication 67, 68 and 69 of the same commission. The correlated used methodology the incorporation of these radionuclides with the activity in organs and you excrete, considering the difference of metabolic behavior of the products of decline and of their predecessor

  4. Irradiator, particularly for calibration of dosimetric devices

    International Nuclear Information System (INIS)

    Brethon, J.-P.; Germond, Philippe; Papot, Lucien.

    1977-01-01

    An irradiator is presented for dosimetric calibration, of the kind comprising one or more radiation emmitting sources, each one placed behind a collimator of which the orifice is covered by a shutter outside the periods of irradiation. This shutter is composed of two preset drop shutters located one behind the other, the drop of the outside curtain of the first shutter causes the beam to pass through and the drop of the internal curtain of the second shutter cuts the beam [fr

  5. A biokinetic and dosimetric model for ionic indium in humans

    Science.gov (United States)

    Andersson, Martin; Mattsson, Sören; Johansson, Lennart; Leide-Svegborn, Sigrid

    2017-08-01

    This paper reviews biokinetic data for ionic indium, and proposes a biokinetic model for systemic indium in adult humans. The development of parameter values focuses on human data and indium in the form of ionic indium(III), as indium chloride and indium arsenide. The model presented for systemic indium is defined by five different pools: plasma, bone marrow, liver, kidneys and other soft tissues. The model is based on two subsystems: one corresponding to indium bound to transferrin and one where indium is transported back to the plasma, binds to red blood cell transferrin and is then excreted through the kidneys to the urinary bladder. Absorbed doses to several organs and the effective dose are calculated for 111In- and 113mIn-ions. The proposed biokinetic model is compared with previously published biokinetic indium models published by the ICRP. The absorbed doses are calculated using the ICRP/ICRU adult reference phantoms and the effective dose is estimated according to ICRP Publication 103. The effective doses for 111In and 113mIn are 0.25 mSv MBq-1 and 0.013 mSv MBq-1 respectively. The updated biokinetic and dosimetric models presented in this paper take into account human data and new animal data, which represent more detailed and presumably more accurate dosimetric data than that underlying previous models for indium.

  6. Determination of dosimetric quantities in pediatric abdominal computed tomography scans.

    Science.gov (United States)

    Jornada, Tiago da Silva; da Silva, Teógenes Augusto

    2014-01-01

    Aiming at contributing to the knowledge on doses in computed tomography (CT), this study has the objective of determining dosimetric quantities associated with pediatric abdominal CT scans, comparing the data with diagnostic reference levels (DRL). The study was developed with a Toshiba Asteion single-slice CT scanner and a GE BrightSpeed multi-slice CT unit in two hospitals. Measurements were performed with a pencil-type ionization chamber and a 16 cm-diameter polymethylmethacrylate trunk phantom. No significant difference was observed in the values for weighted air kerma index (CW), but the differences were relevant in values for volumetric air kerma index (CVOL), air kerma-length product (PKL,CT) and effective dose. Only the CW values were lower than the DRL, suggesting that dose optimization might not be necessary. However, PKL,CT and effective dose values stressed that there still is room for reducing pediatric radiation doses. The present study emphasizes the importance of determining all dosimetric quantities associated with CT scans.

  7. Determination of dosimetric quantities in pediatric abdominal computed tomography scans*

    Science.gov (United States)

    Jornada, Tiago da Silva; da Silva, Teógenes Augusto

    2014-01-01

    Objective Aiming at contributing to the knowledge on doses in computed tomography (CT), this study has the objective of determining dosimetric quantities associated with pediatric abdominal CT scans, comparing the data with diagnostic reference levels (DRL). Materials and methods The study was developed with a Toshiba Asteion single-slice CT scanner and a GE BrightSpeed multi-slice CT unit in two hospitals. Measurements were performed with a pencil-type ionization chamber and a 16 cm-diameter polymethylmethacrylate trunk phantom. Results No significant difference was observed in the values for weighted air kerma index (CW), but the differences were relevant in values for volumetric air kerma index (CVOL), air kerma-length product (PKL,CT) and effective dose. Conclusion Only the CW values were lower than the DRL, suggesting that dose optimization might not be necessary. However, PKL,CT and effective dose values stressed that there still is room for reducing pediatric radiation doses. The present study emphasizes the importance of determining all dosimetric quantities associated with CT scans. PMID:25741103

  8. Determination of dosimetric quantities in pediatric abdominal computed tomography scans

    Energy Technology Data Exchange (ETDEWEB)

    Jornada, Tiago da Silva [Universidade Federal de Sao Paulo (UNIFESP), Sao Paulo, SP (Brazil). Escola Paulista de Medicina. Dept. de Diagnostipo por Imagem; Silva, Teogenes Augusto da, E-mail: silvata@cdtn.br [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)

    2014-09-15

    Objective: aiming at contributing to the knowledge on doses in computed tomography (CT), this study has the objective of determining dosimetric quantities associated with pediatric abdominal CT scans, comparing the data with diagnostic reference levels (DRL). Materials and methods: the study was developed with a Toshiba Asteion single-slice CT scanner and a GE BrightSpeed multi-slice CT unit in two hospitals. Measurements were performed with a pencil-type ionization chamber and a 16 cm-diameter polymethylmethacrylate trunk phantom. Results: No significant difference was observed in the values for weighted air kerma index (C{sub W}), but the differences were relevant in values for volumetric air kerma index (C{sub VOL}), air kerma-length product (P{sub KL,CT}) and effective dose. Conclusion: Only the CW values were lower than the DRL, suggesting that dose optimization might not be necessary. However, P{sub KL,CT} and effective dose values stressed that there still is room for reducing pediatric radiation doses. The present study emphasizes the importance of determining all dosimetric quantities associated with CT scans. (author)

  9. Development of a WebQuest as instructional material in teaching biodiversity for grade 8 learners

    Science.gov (United States)

    Genovia, Jerson A.; Eslit, April Rose C.; Tamse, Agnes Lera G.; Barquilla, Manuel B.

    2018-01-01

    WebQuest is an inquiry-based learning activity that allows students to learn the lesson using the information provided in the internet resources. The study aimed to develop and implement the WebQuest on Biodiversity. Primarily, this research determines the students' performances in the achievement test after WebQuest was implemented to them. Secondly, it is also to investigate on their attitudes towards Biology before and after the activity as well as the level of development of their 21st Century Skills. This research utilized Quasi-experimental Non-randomized One Group Pretest/Posttest Design. The developed WebQuest that is based from the K-12 curriculum competencies were evaluated by selected experts in the Content (2), Pedagogy (2) and ICT (2) to assess the said activity in terms of content, pedagogy and ICT effects. It was then implemented in an intact group of grade 8 students. Findings revealed that the developed WebQuest was rated "Excellent" for Content, Pedagogy and TCT effects. After utilizing the WebQuest activity on Biodiversity, students acquired more knowledge on the topic shows by the mean difference of 2.42, which is highly significant based on t-test result. The overall students' attitude towards Biology as a subject changed positively after they did the activity due to novelty effects and the WebQuest itself with the mean difference of 0.46. Moreover, results shows that the students can developed 21st century skills considering that the Likert scale survey was given only to the students after the activity. Based on the result, 97% of total responses favored to have developed Critical Thinking skills, 98% on Collaboration skills, 97% on Creativity and Innovative skills, 94% on Communication skills, 97% on Self-Decision skills, and 97% on ICT skills. The concentration of percentage of responses differed in two classes because Class A was composed of highlyselected students who underwent an entrance examination upon admission in school and Class B

  10. MONITORING THE DEVELOPMENT DYNAMICS OF CERTAIN ANTHROPOLOGICAL DIMENSIONS IN PUPILS OF HIGHER GRADES IN ELEMENTARY SCHOOL

    Directory of Open Access Journals (Sweden)

    Dževad Džibrić

    2012-09-01

    Full Text Available The objective of this research was to determine the dynamics of changes in certain anthropological dimensions in pupils of higher grades in Elementary schools of Tuzla. Population from which the sample was taken for this study represent the boys of the fifth, sixth, seventh and eight grade of Tuzla city schools. The study was conducted on a total of 895 subjects, 11-14 years of age. We applied 11 variables suggested by Eurofit battery tests which are as follows: morphological characteristics (2 variables, basic motor skills (8 variables and one variable for functional skill assessment. With multivariate and univariate covariance analysis we obtained information at what age the boys have the highest growth rate of treated anthropological dimensions. The highest growth rate of body height is in the eight grade, since in this period, the impact of pubertal changes is the most intense. The highest growth rate in variables of basicmotor skill assessment is recorded in the sixth and eight grade, and in variables for functional skill assessment – running with progressive acceleration was recorded in boys of the sixth grade.

  11. Development and characterization of food-grade tracers for the global grain tracing and recall system.

    Science.gov (United States)

    Lee, Kyung-Min; Armstrong, Paul R; Thomasson, J Alex; Sui, Ruixiu; Casada, Mark; Herrman, Timothy J

    2010-10-27

    Tracing grain from the farm to its final processing destination as it moves through multiple grain-handling systems, storage bins, and bulk carriers presents numerous challenges to existing record-keeping systems. This study examines the suitability of coded caplets to trace grain, in particular, to evaluate methodology to test tracers' ability to withstand the rigors of a commercial grain handling and storage systems as defined by physical properties using measurement technology commonly applied to assess grain hardness and end-use properties. Three types of tracers to dispense into bulk grains for tracing the grain back to its field of origin were developed using three food-grade substances [processed sugar, pregelatinized starch, and silicified microcrystalline cellulose (SMCC)] as a major component in formulations. Due to a different functionality of formulations, the manufacturing process conditions varied for each tracer type, resulting in unique variations in surface roughness, weight, dimensions, and physical and spectroscopic properties before and after coating. The applied two types of coating [pregelatinized starch and hydroxypropylmethylcellulose (HPMC)] using an aqueous coating system containing appropriate plasticizers showed uniform coverage and clear coating. Coating appeared to act as a barrier against moisture penetration, to protect against mechanical damage of the surface of the tracers, and to improve the mechanical strength of tracers. The results of analysis of variance (ANOVA) tests showed the type of tracer, coating material, conditioning time, and a theoretical weight gain significantly influenced the morphological and physical properties of tracers. Optimization of these factors needs to be pursued to produce desirable tracers with consistent quality and performance when they flow with bulk grains throughout the grain marketing channels.

  12. Developing Self-Assessment Skills in Grade 3 Science and Technology: The Importance of Longitudinal Studies of Learning.

    Science.gov (United States)

    Rudd, Telsa J.; Gunstone, Richard F.

    A year-long study in 1991 that aimed to develop self-assessment skills in one third-grade class in Australia is reported. The roles that the length and naturalistic features of the study played in the success of skill development are explored. The class contained 20 students, ages 8-9 years, present for the whole school year (four 11-week terms).…

  13. The Development and Production of a Functionally Graded Composite for Pb-Bi Service

    Energy Technology Data Exchange (ETDEWEB)

    Ballinger, Ronald G

    2011-08-01

    A material that resists lead-bismuth eutectic (LBE) attack and retains its strength at 700°C would be an enabling technology for LBE-cooled reactors. No single alloy currently exists that can economically meet the required performance criteria of high strength and corrosion resistance. A Functionally Graded Composite (FGC) was developed with layers engineered to perform these functions. F91 was chosen as the structural layer of the composite for its strength and radiation resistance. Fe-12Cr-2Si, an alloy developed from previous work in the Fe-Cr-Si system, was chosen as the corrosion-resistant cladding layer because of its chemical similarity to F91 and its superior corrosion resistance in both oxidizing and reducing environments. Fe-12Cr-2Si experienced minimal corrosion due to its self-passivation in oxidizing and reducing environments. Extrapolated corrosion rates are below one micron per year at 700ï°C. Corrosion of F91 was faster, but predictable and manageable. Diffusion studies showed that 17 microns of the cladding layer will be diffusionally diluted during the three year life of fuel cladding. 33 microns must be accounted for during the sixty year life of coolant piping. 5 cm coolant piping and 6.35 mm fuel cladding preforms were produced on a commercial scale by weld-overlaying Fe-12Cr-2Si onto F91 billets and co-extruding them. An ASME certified weld was performed followed by the prescribed quench-and-tempering heat treatment for F91. A minimal heat affected zone was observed, demonstrating field weldability. Finally, corrosion tests were performed on the fabricated FGC at 700ï°C after completely breaching the cladding in a small area to induce galvanic corrosion at the interface. None was observed. This FGC has significant impacts on LBE reactor design. The increases in outlet temperature and coolant velocity allow a large increase in power density, leading to either a smaller core for the same power rating or more power output for the same size

  14. Formative Assessment of Collaborative Teams (FACT): Development of a Grade-Level Instructional Team Checklist

    Science.gov (United States)

    Taylor, Matthew J.; Hallam, Pamela R.; Charlton, Cade T.; Wall, D. Gary

    2014-01-01

    Professional Learning Communities (PLCs) have become increasingly popular in schools. PLCs are groups of teachers, administrators, parents, and students who collaborate to improve their practices and focus on results (DuFour, 2004). Grade-level and department teachers participate in regularly scheduled collaborative team meetings; however, many…

  15. How executive functions predict development in syntactic complexity of narrative writing in the upper elementary grades

    NARCIS (Netherlands)

    Drijbooms, E.; Groen, M.A.; Verhoeven, L.T.W.

    2017-01-01

    The aim of this study was to examine the contribution of transcription skills, oral language skills, and executive functions to growth in narrative writing between fourth and sixth grade. While text length and story content of narratives did not increase with age, syntactic complexity of narratives

  16. The Influence of Morphological Awareness on the Literacy Development of First-Grade Children

    Science.gov (United States)

    Wolter, Julie A.; Wood, Alexis; D'zatko, Kim W.

    2009-01-01

    Purpose: The purpose of this study was twofold. First, we investigated whether first-grade children evidenced morphological awareness and whether they used their knowledge of morphological relations to guide their spelling. Second, we sought to determine whether children's morphological awareness abilities were predictive of their performance on…

  17. Developing Essential Understanding of Multiplication and Division for Teaching Mathematics in Grades 3-5

    Science.gov (United States)

    Otto, Albert; Caldwell, Janet; Hancock, Sarah Wallus; Zbiek, Rose Mary

    2011-01-01

    This book identifies and examines two big ideas and related essential understandings for teaching multiplication and division in grades 3-5. Big Idea 1 captures the notion that multiplication is usefully defined as a scalar operation. Problem situations modeled by multiplication have an element that represents the scalar and an element that…

  18. Evaluating Fifth- and Sixth-Grade Students' Expository Writing: Task Development, Scoring, and Psychometric Issues

    Science.gov (United States)

    Kulikowich, Jonna M.; Mason, Linda H.; Brown, Scott W.

    2008-01-01

    Drawing from multiple theoretical frameworks representing cognitive and educational psychology, we present a writing task and scoring system for measurement of students' informative writing. Participants in this study were 72 fifth- and sixth-grade students who wrote compositions describing real-world problems and how mathematics, science, and…

  19. Screening of various low-grade biomass materials for low temperature gasification: Method development and application

    DEFF Research Database (Denmark)

    Thomsen, Tobias Pape; Ravenni, Giulia; Holm, Jens Kai

    2015-01-01

    method and the subsequent use of the method to identify promising e but currently unproven, low-grade biomass resources for conversion in Pyroneer systems. The technical assessment is conducted by comparing the results from a series of physical-mechanical and thermochemical experiments to a set of proven...

  20. Starting Young: Massachusetts Birth-3rd Grade Policies That Support Children's Literacy Development

    Science.gov (United States)

    Cook, Shayna; Bornfreund, Laura

    2015-01-01

    Massachusetts is one of a handful of states that is often recognized as a leader in public education, and for good reason. The Commonwealth consistently outperforms most states on national reading and math tests and often leads the pack in education innovations. "Starting Young: Massachusetts Birth-3rd Grade Policies that Support Children's…

  1. DEVELOPING SIGNS AND SONGS MATERIALS DEALING WITH THE 2013 CURRICULUM FOR THE SEVENTH GRADE STUDENTS IN MTSN BALANG-BALANG

    Directory of Open Access Journals (Sweden)

    Mardiana

    2016-04-01

    Full Text Available This research aimed to develop Signs and Songs Materials based on 2013 curriculum for the Seventh Grade Student at MTsN. BalangBalang, Gowa. It was Research and Development (R&D applied ADDIE model standing for Analysis, Design, Develop, Implement, and Evaluate. The procedures were; 1 analyzing materials needed by students; 2designing the blueprint; 3 developing the materials through the syllabus of 2013 Curriculum; 4 implementing the product (try-out product; and 5 evaluating the product. The product was tried out to the seventh grade students at MTsN Balang-balang. Type of data obtained in this study was qualitative. The instruments used in this study were questionnaire and rubrics for teacher and expert. Then, the teacher and expert were involved in order to validate the product. They validated three systematic aspects of the product, namely; the organization of the Materials, English Teaching strategies or method, and the content of the materials. Finally, based on the teacher and expert judgment as well as try-out design result, it was found that the developed materials were applicable to be taught for the Seventh Grade of Junior High School as additional learning and teaching materials which help both students and teachers in learning process based on 2013 Curriculum.

  2. High-Dose and Extended-Field Intensity Modulated Radiation Therapy for Early-Stage NK/T-Cell Lymphoma of Waldeyer's Ring: Dosimetric Analysis and Clinical Outcome

    Energy Technology Data Exchange (ETDEWEB)

    Bi, Xi-Wen; Li, Ye-Xiong, E-mail: yexiong@yahoo.com; Fang, Hui; Jin, Jing; Wang, Wei-Hu; Wang, Shu-Lian; Liu, Yue-Ping; Song, Yong-Wen; Ren, Hua; Dai, Jian-Rong

    2013-12-01

    Purpose: To assess the dosimetric benefit, treatment outcome, and toxicity of high-dose and extended-field intensity modulated radiation therapy (IMRT) in patients with early-stage NK/T-cell lymphoma of Waldeyer's ring (WR-NKTCL). Methods and Materials: Thirty patients with early-stage WR-NKTCL who received extended-field IMRT were retrospectively reviewed. The prescribed dose was 50 Gy to the primary involved regions and positive cervical lymph nodes (planning target volume requiring radical irradiation [PTV{sub 50}]) and 40 Gy to the negative cervical nodes (PTV{sub 40}). Dosimetric parameters for the target volume and critical normal structures were evaluated. Locoregional control (LRC), overall survival (OS), and progression-free survival (PFS) were calculated using the Kaplan-Meier method. Results: The median mean doses to the PTV{sub 50} and PTV{sub 40} were 53.2 Gy and 43.0 Gy, respectively. Only 1.4% of the PTV{sub 50} and 0.9% of the PTV{sub 40} received less than 95% of the prescribed dose, indicating excellent target coverage. The average mean doses to the left and right parotid glands were 27.7 and 28.4 Gy, respectively. The 2-year OS, PFS, and LRC rates were 71.2%, 57.4%, and 87.8%. Most acute toxicities were grade 1 to 2, except for grade ≥3 dysphagia and mucositis. The most common late toxicity was grade 1-2 xerostomia, and no patient developed any ≥grade 3 late toxicities. A correlation between the mean dose to the parotid glands and the degree of late xerostomia was observed. Conclusions: IMRT achieves excellent target coverage and dose conformity, as well as favorable survival and locoregional control rates with acceptable toxicities in patients with WR-NKTCL.

  3. The Development of K-8 Progress Monitoring Measures in Mathematics for Use with the 2% and General Education Populations: Grade 8. Technical Report # 09-04

    Science.gov (United States)

    Lai, Cheng Fei; Alonzo, Julie; Tindal, Gerald

    2009-01-01

    In this technical report, we describe the development and piloting of a series of mathematics progress monitoring measures intended for use with students in grades kindergarten through eighth grade. These measures, available as part of easyCBM[TM], an online progress monitoring assessment system, were developed in 2007 and 2008 and administered to…

  4. The Development of K-8 Progress Monitoring Measures in Mathematics for Use with the 2% and General Education Populations: Grade 5. Technical Report # 09-01

    Science.gov (United States)

    Lai, Cheng Fei; Alonzo, Julie; Tindal, Gerald

    2009-01-01

    In this technical report, we describe the development and piloting of a series of mathematics progress monitoring measures intended for use with students in grades kindergarten through eighth grade. These measures, available as part of easyCBM[TM], an online progress monitoring assessment system, were developed in 2007 and 2008 and administered to…

  5. The Development of K-8 Progress Monitoring Measures in Mathematics for Use with the 2% and General Education Populations: Grade 3. Technical Report # 09-02

    Science.gov (United States)

    Alonzo, Julie; Lai, Cheng Fei; Tindal, Gerald

    2009-01-01

    In this technical report, we describe the development and piloting of a series of mathematics progress monitoring measures intended for use with students in grades kindergarten through eighth grade. These measures, available as part of easyCBM[TM], an online progress monitoring assessment system, were developed in 2007 and 2008 and administered to…

  6. The Development of K-8 Progress Monitoring Measures in Mathematics for Use with the 2% and General Education Populations: Grade 4. Technical Report # 09-03

    Science.gov (United States)

    Alonzo, Julie; Lai, Cheng Fei; Tindal, Gerald

    2009-01-01

    In this technical report, we describe the development and piloting of a series of mathematics progress monitoring measures intended for use with students in grades kindergarten through eighth grade. These measures, available as part of easyCBM[TM], an online progress monitoring assessment system, were developed in 2007 and 2008 and administered to…

  7. The Development of K-8 Progress Monitoring Measures in Mathematics for Use with the 2% and General Education Populations: Grade 2. Technical Report # 0920

    Science.gov (United States)

    Alonzo, Julie; Lai, Cheng Fei; Tindal, Gerald

    2009-01-01

    In this technical report, we describe the development and piloting of a series of mathematics progress monitoring measures intended for use with students in grades kindergarten through eighth grade. These measures, available as part of easyCBM[TM], an online progress monitoring assessment system, were developed in 2007 and 2008 and administered to…

  8. The Development of K-8 Progress Monitoring Measures in Mathematics for Use with the 2% and General Education Populations: Grade 7. Technical Report 0908

    Science.gov (United States)

    Lai, Cheng Fei; Alonzo, Julie; Tindal, Gerald

    2009-01-01

    In this technical report, we describe the development and piloting of a series of mathematics progress monitoring measures intended for use with students in grades kindergarten through eighth grade. These measures, available as part of easyCBM[TM], an online progress monitoring assessment system, were developed in 2007 and 2008 and administered to…

  9. Gamma dosimetric parameters in some skeletal muscle relaxants

    Indian Academy of Sciences (India)

    ... air kerma strength and dose rate are evaluated from the measured mass attentuation coefficient. These measured gamma dosimetric parameters are compared with the theoretical values. The measured values agree with the theoretical values. The studied gamma dosimetric values for the relaxants are useful in medical ...

  10. Incorrect dosimetric leaf separation in IMRT and VMAT treatment planning

    DEFF Research Database (Denmark)

    Sjölin, Maria; Edmund, Jens Morgenthaler

    2016-01-01

    PURPOSE: Dynamic treatment planning algorithms use a dosimetric leaf separation (DLS) parameter to model the multi-leaf collimator (MLC) characteristics. Here, we quantify the dosimetric impact of an incorrect DLS parameter and investigate whether common pretreatment quality assurance (QA) method...

  11. Dosimetric evaluation of an automatic segmentation tool of pelvic structures from MRI images for prostate cancer radiotherapy

    International Nuclear Information System (INIS)

    Pasquier, D.; Lacornerie, T.; Lartigau, E.; Pasquier, D.; Pasquier, D.; Betrouni, N.; Vermandel, M.; Rousseau, J.

    2008-01-01

    Purpose: An automatic segmentation tool of pelvic structures from MRI images for prostate cancer radiotherapy was developed and dosimetric evaluation of differences of delineation (automatic versus human) is presented here. Materials and methods: C.T.V. (clinical target volume), rectum and bladder were defined automatically and by a physician in 20 patients. Treatment plans based on 'automatic' volumes were transferred on 'manual' volumes and reciprocally. Dosimetric characteristics of P.T.V. (V.95, minimal, maximal and mean doses), rectum (V.50, V.70, maximal and mean doses) and bladder (V.70, maximal and mean doses) were compared. Results: Automatic delineation of C.T.V. did not significantly influence dosimetric characteristics of 'manual' P.T.V. (projected target volume). Rectal V-50 and V.70 were not significantly different; mean rectal dose is slightly superior (43.2 versus 44.4 Gy, p = 0.02, Student test). Bladder V.70 was significantly superior too (19.3 versus 21.6, p = 0.004). Organ-at-risk (O.A.R.) automatic delineation had little influence on their dosimetric characteristics; rectal V.70 was slightly underestimated (20 versus 18.5 Gy, p = 0.001). Conclusion: C.T.V. and O.A.R. automatic delineation had little influence on dosimetric characteristics. Software developments are ongoing to enable routine use and interobserver evaluation is needed. (authors)

  12. Dosimetric adaptive IMRT driven by fiducial points

    International Nuclear Information System (INIS)

    Crijns, Wouter; Van Herck, Hans; Defraene, Gilles; Van den Bergh, Laura; Haustermans, Karin; Slagmolen, Pieter; Maes, Frederik; Van den Heuvel, Frank

    2014-01-01

    Purpose: Intensity modulated radiotherapy (IMRT) and volumetric modulated arc therapy have become standard treatments but are more sensitive to anatomical variations than 3D conformal techniques. To correct for inter- and intrafraction anatomical variations, fast and easy to implement methods are needed. Here, the authors propose a full dosimetric IMRT correction that finds a compromise in-between basic repositioning (the current clinical practice) and full replanning. It simplifies replanning by avoiding a recontouring step and a full dose calculation. It surpasses repositioning by updating the preoptimized fluence and monitor units (MU) using a limited number of fiducial points and a pretreatment (CB)CT. To adapt the fluence the fiducial points were projected in the beam's eye view (BEV). To adapt the MUs, point dose calculation towards the same fiducial points were performed. The proposed method is intrinsically fast and robust, and simple to understand for operators, because of the use of only four fiducial points and the beam data based point dose calculations. Methods: To perform our dosimetric adaptation, two fluence corrections in the BEV are combined with two MU correction steps along the beam's path. (1) A transformation of the fluence map such that it is realigned with the current target geometry. (2) A correction for an unintended scaling of the penumbra margin when the treatment beams scale to the current target size. (3) A correction for the target depth relative to the body contour and (4) a correction for the target distance to the source. The impact of the correction strategy and its individual components was evaluated by simulations on a virtual prostate phantom. This heterogeneous reference phantom was systematically subjected to population based prostate transformations to simulate interfraction variations. Additionally, a patient example illustrated the clinical practice. The correction strategy was evaluated using both dosimetric

  13. The development of an outcomes-based grade 12, English as an additional language, question paper

    OpenAIRE

    2011-01-01

    M.Ed. Although the language assessment procedures for South African Grade12 learners have been extensively investigated by language practitioners, additional research is required in order to enhance assessment procedures and questioning techniques so that attitudes, values and learners' observable knowledge be included in testing. This study addresses the deficiencies associated with the existing assessment and evaluation techniques as related to English Second Language examinations. In th...

  14. The Modified Attitudes Toward Science Inventory: Developing AN Instrument to BE Used with Fifth Grade Urban Students

    Science.gov (United States)

    Weinburgh, Molly H.; Steele, Donald

    The purpose of this study was to develop an attitudinal instrument that could be used over the course of a funded local systemic change project to measure the changes in attitudes toward science of African-American fifth grade students. After examining many instruments, we modified an existing one so that it retained acceptable reliability for fifth grade students, both males and females, in an urban school district. The modified instrument was short enough so that young students who often have short attention spans would not become inattentive. We shortened the Attitudes Toward Science Inventory: version A (ATSI:a), a 48-item Likert-scale instrument to 25 items, and designated it the Modified Attitudes Toward Science Inventory (mATSI). We selected the ATSI:a because of its multidimensional nature and our belief that attitudes toward science cannot be measured on a single scale. Two phases were used for the modification: (a) after establishing that the ATSI:a was reliable for males and females and African-American middle grades students, we conducted a factor analysis to select an appropriate subset of items to form the shortened version, and (b) we administered this shortened version to a pilot group of African-American fifth grade students. Reliability was established using Cronbach's alpha. The new version, mATSI, cut administration time from 60 to 40 minutes. It also retained alpha coefficients on all five scales above the 0.50 minimum level set by McMillan and Schmacher (1993) and Nunnally (1967) for attitudinal instruments when sorted by ethnicity and gender for a sample of fifth grade students.

  15. Effectiveness of Motor Skills Development in 5th-7th Grade Girls at Different Modes of Physical Exercises

    Directory of Open Access Journals (Sweden)

    Olga Ivashchenko

    2017-12-01

    Full Text Available The objective is to determine the influence of the physical exercises modes on effectiveness of motor skills development in 5th-7th grade girls.  Materials and methods. The study involved 5th grade girls (n = 28, 6th grade girls (n = 28 and 7th grade girls (n = 24. To solve the tasks set, the study relied on general scientific and special research methods, methods of mathematical experiment-planning. Studying the influence of different variants of the educational process structure, namely: the number of repetitions (x1 and the rest intervals (x2 on acquisition of the technique of physical exercises performance, provided for achieving the objective. A full 22 type factorial experiment was conducted. The 5th-7th graders were divided into training groups according to the experiment plan. In total, there were twelve experimental groups organized, four in each class. Results. The analysis of the regression equations shows that the rest interval between repetitions (x2 has the greatest influence on teaching 5th-7th grade girls physical exercises, with the number of repetitions (x1 being of somewhat less significant influence. The relation between these factors (x1x2 has a considerable weight in teaching to “rope climb in two or three sets” and to do a “pullover mount with a swing of one and a push-off with the other leg”. Conclusions. To increase the effectiveness of teaching 5th-7th grade girls physical exercises, the number of repetitions in throwing exercises should be increased to twelve times, and the rest interval reduced to 60 seconds. In the 7th grade, the number of repetitions should be reduced to six times, and the rest interval – to 60 seconds. The rest intervals in the exercises: “pullover mount with a swing of one and a push-off with the other leg” and “rope climbing in two or three sets”, should be reduced to 60 seconds and the number of repetitions – to six.

  16. Longitudinal Associations Between Objectively Measured Physical Activity and Development of Executive Functioning Across the Transition to First Grade.

    Science.gov (United States)

    Vandenbroucke, Loren; Seghers, Jan; Verschueren, Karine; Wijtzes, Anne I; Baeyens, Dieter

    2016-08-01

    The current study investigates how children's amount of daily physical activity relates to subcomponents of executive functions, the cognitive processes needed for goal-directed behavior. Previous studies rarely determined this association at the subcomponent level and did not explicitly examine the period when children make the transition to first grade, despite its importance for the development of executive functions. In a sample of 54 children, working memory, inhibition, and cognitive flexibility were thoroughly measured at the subcomponent level at the end of kindergarten and first grade. In the middle of first grade, children wore a pedometer for 7 consecutive days. Regression analyses showed that performance on a measure of the visuospatial sketchpad, the central executive, and fluency was predicted by children's amount of daily physical activity after controlling for initial task performance. The development of the visuospatial sketchpad (working memory), the central executive (working memory), and fluency (cognitive flexibility) might be improved by increasing the amount of time being physically active. However, as other subcomponents of executive functioning were not affected, the role of other aspects of physical activity, such as intensity and content, in the development of executive functions should be further investigated.

  17. Dosimetric and clinical results of three-dimensional conformal radiotherapy for locally recurrent nasopharyngeal carcinoma

    International Nuclear Information System (INIS)

    Zheng Xiaokang; Ma Jun; Chen Longhua; Xia Yunfei; Shi Yusheng

    2005-01-01

    Purpose: To assess the dosimetric and clinical results of three-dimensional conformal radiotherapy (3D CRT) for locally recurrent nasopharyngeal carcinoma (NPC). Methods: A total of 86 patients with locally recurrent NPC were retreated with 3D CRT. The median prescribed dose was 68 Gy with 2 Gy per fractionation. Dosimetric quality was evaluated with dose distribution in planning target volume (PTV) and specified organs at risk (OAR), dose conformity index (CI) and dose homogeneity index (HI). The actuarial rate of local failure-free (LFF), overall survival (OS) and major late toxicities (MLT) were estimated with Kaplan-Meier method. Multivariate analysis for prognosis was performed using the Cox regression proportional hazards model. Results: The mean dose to PTV averaged 66.8 Gy, and the dose to specified OAR was acceptable. The average value of CI and HI was 0.59 and 9.1%. The 5-year actuarial rate of LFF and OS was 71 and 40%, respectively. The 5-year actuarial incidence of MLT≥Grade 3 and ≥Grade 4 were 100 and 49%, respectively. The major prognostic factors were T stage and the size of gross tumor volume (GTV). Advanced T stage and large GTV volume were associated with poor LFF and OS and high risk of MLT. Conclusion: The dosimetric quality of 3D CRT for locally recurrent NPC is generally excellent. A relatively high local control was achieved with this technique. However, the incidence of late toxicities were not found to decrease as originally expected. Early diagnosis of the recurrence and reasonable definition of the target volume are crucial to achieve a better outcome

  18. Beam standardization and dosimetric methodology in computed tomography

    International Nuclear Information System (INIS)

    Maia, Ana Figueiredo

    2005-01-01

    Special ionization chambers, named pencil ionization chambers, are used in dosimetric procedures in computed tomography beams (CT). In this work, an extensive study about pencil ionization chambers was performed, as a contribution to the accuracy of the dosimetric procedures in CT beams. The international scientific community has recently been discussing the need of the establishment of a specific calibration procedure for CT ionization chambers, once these chambers present special characteristics that differentiate them from other ionization chambers used in diagnostic radiology beams. In this work, an adequate calibration procedure for pencil ionization chambers was established at the Calibration Laboratory, of the Institute de Pesquisas Energeticas e Nucleares, in accordance with the most recent international recommendations. Two calibration methodologies were tested and analyzed by comparative studies. Moreover, a new extended length parallel plate ionization chamber, with a transversal section very similar to pencil ionization chambers, was developed. The operational characteristics of this chamber were determined and the results obtained showed that its behaviour is adequate as a reference system in CT standard beams. Two other studies were performed during this work, both using CT ionization chambers. The first study was about the performance of a pencil ionization chamber in standard radiation beams of several types and energies, and the results showed that this chamber presents satisfactory behaviour in other radiation qualities as of diagnostic radiology, mammography and radiotherapy. In the second study, a tandem system for verification of hal'-value layer variations in CT equipment, using a pencil ionization chamber, was developed. Because of the X rays tube rotation, the determination of half-value layers in computed tomography equipment is not an easy task, and it is usually not performed within quality control programs. (author)

  19. Identifying the Dimensionality of Oral Language Skills of Children With Typical Development in Preschool Through Fifth Grade.

    Science.gov (United States)

    Lonigan, Christopher J; Milburn, Trelani F

    2017-08-16

    Language is a multidimensional construct from prior to the beginning of formal schooling to near the end of elementary school. The primary goals of this study were to identify the dimensionality of language and to determine whether this dimensionality was consistent in children with typical language development from preschool through 5th grade. In a large sample of 1,895 children, confirmatory factor analysis was conducted with 19-20 measures of language intended to represent 6 factors, including domains of vocabulary and syntax/grammar across modalities of expressive and receptive language, listening comprehension, and vocabulary depth. A 2-factor model with separate, highly correlated vocabulary and syntax factors provided the best fit to the data, and this model of language dimensionality was consistent from preschool through 5th grade. This study found that there are fewer dimensions than are often suggested or represented by the myriad subtests in commonly used standardized tests of language. The identified 2-dimensional (vocabulary and syntax) model of language has significant implications for the conceptualization and measurement of the language skills of children in the age range from preschool to 5th grade, including the study of typical and atypical language development, the study of the developmental and educational influences of language, and classification and intervention in clinical practice. https://doi.org/10.23641/asha.5154220.

  20. Development of medical guide wire of Cu-Al-Mn-base superelastic alloy with functionally graded characteristics.

    Science.gov (United States)

    Sutou, Yuji; Omori, Toshihiro; Furukawa, Akihisa; Takahashi, Yukinori; Kainuma, Ryosuke; Yamauchi, Kiyoshi; Yamashita, Shuzo; Ishida, Kiyohito

    2004-04-15

    A new type of medical guide wire with functionally graded hardness from the tip to the end was developed with the use of Cu-Al-Mn-based alloys. The superelasticity (SE) of the Cu-Al-Mn-based alloys in the tip is drastically improved by controlling the grain size, whereas the end of the wire is hardened using bainitic transformation by aging at around 200-400 degrees C. Therefore, the tip of the guide wire shows a superelasticity and its end has high stiffness. This guide wire with functionally graded characteristics shows excellent pushability and torquability, superior to that of the Ni-Ti guide wire. Copyright 2004 Wiley Periodicals, Inc.

  1. ESR dosimetric properties of modern coral reef

    Energy Technology Data Exchange (ETDEWEB)

    Sharaf, M.A. E-mail: mokhtar_sharaf@yahoo.com; Hassan, Gamal M

    2004-06-01

    Modern coral reef samples from Egypt were irradiated with {sup 60}Co{gamma}-rays to study radicals for dosimetric materials with electron spin resonance (ESR). The ESR spectrum for the radical species in unirradiated coral is characterized by four signals with spectroscopic splitting factors of g=2.0056, 2.0030, 2.0006 and 1.997. The signal at g=2.0006{+-}0.0005 is ascribed to free rotation CO{sub 2}{sup -} radicals and used as a dosimetric one. The response to {gamma}-ray doses ranging from 5 to 10{sup 3} Gy and the thermal stability has been studied. The number of free radicals per 100 eV (G-value) was found to be 0.45 {+-} 0.1 and 0.9 {+-} 0.18 for coral and alanine, respectively. The lifetime of radicals and the activation energy were estimated from Arrhenius plots to be approximately 8 x 10{sup 5} {+-} 1.6 x 10{sup 5} years, and 1.12 eV, respectively.

  2. STEM development: A study of 6th--12th grade girls' interest and confidence in mathematics and science

    Science.gov (United States)

    Heaverlo, Carol Ann

    Researchers, policymakers, business, and industry have indicated that the United States will experience a shortage of professionals in the Science, Technology, Engineering, and Mathematics (STEM) fields. Several strategies have been suggested to address this shortage, one of which includes increasing the representation of girls and women in the STEM fields. In order to increase the representation of women in the STEM fields, it is important to understand the developmental factors that impact girls' interest and confidence in STEM academics and extracurricular programs. Research indicates that greater confidence leads to greater interest and vice versa (Denissen et al., 2007). This study identifies factors that impact girls' interest and confidence in mathematics and science, defined as girls' STEM development. Using Bronfenbrenner's (2005) bioecological model of human development, several factors were hypothesized as having an impact on girls' STEM development; specifically, the macrosystems of region of residence and race/ethnicity, and the microsystems of extracurricular STEM activities, family STEM influence, and math/science teacher influence. Hierarchical regression analysis results indicated that extracurricular STEM involvement and math teacher influence were statistically significant predictors for 6--12th grade girls' interest and confidence in mathematics. Furthermore, hierarchical regression analysis results indicated that the only significant predictor for 6--12th grade girls' interest and confidence in science was science teacher influence. This study provides new knowledge about the factors that impact girls' STEM development. Results can be used to inform and guide educators, administrators, and policy makers in developing programs and policy that support and encourage the STEM development of 6--12th grade girls.

  3. Dosimetric model for intravascular brachytherapy

    International Nuclear Information System (INIS)

    Flower, E.E.; Stroud, D.B.

    2000-01-01

    Full text: Intravascular brachytherapy has been shown to be a prophylaxis for restenosis. Adventitial macrophages, which are extremely radiosensitive, initiate neointima formation. A model of the dose levels of the treatment range is developed, assuming that the adventitia is the target tissue. If the adventitia receives a dose of less than 10 Gy, it is assumed the treatment will be ineffective. If the dose to any part of the wall is above 30 Gy, it is assumed that the treatment could be detrimental. Hence the treatment range is between 10 and 30 Gy, with 20 Gy being the optimum dosage to the adventitia. An algorithm using numerical integration of published dose kernels calculates the dose at any point surrounding a beta ( 32 P) line source of finite length. Dose profiles were obtained to demonstrate edge effects. For long lesions, the source is often stepped along the artery. Dose changes due to separation or overlapping of sources during source stepping procedures were also determined. Isodose curves were superimposed on intravascular ultrasound images to demonstrate dose levels. For an exposure time of 60 seconds with a 200mCi source, the optimum dose of 20 Gy occurs at a distance 1.94mm from the centre of the source. The upper limit of the treatment dose range (30 Gy) occurs at 1.59mm. The lower limit of the treatment dose range (10 Gy) occurs at 2.7mm. Significant perturbations to the treatment dose range can be caused by non-centering of the source, edge effects and separation or overlapping of sources in stepping procedures. Despite these concerns, many successful procedures have been reported and this implies that the model is over simplified and requires modifications. Copyright (2000) Australasian College of Physical Scientists and Engineers in Medicine

  4. Dosimetric study for characterization of a postal system of quality control in brachytherapy; Estudo dosimetrico para caracterizacao de um sistema postal de controle de qualidade em braquiterapia

    Energy Technology Data Exchange (ETDEWEB)

    Alves, Victor Gabriel Leandro, E-mail: vgalves@inca.gov.b [Instituto Nacional do Cancer (INCa), Rio de Janeiro, RJ (Brazil); Queiroz Filho, Pedro Pacheco de; Santos, Denison de Souza, E-mail: queiroz@ird.gov.b, E-mail: santosd@ird.gov.b [Instituto de Radioprotecao e Dosimetria (IRD/CNEN-RJ), Rio de Janeiro, RJ (Brazil); Begalli, Marcia, E-mail: begalli@uerj.b [Universidade do Estado do Rio de Janeiro (IF/UERJ), RJ (Brazil). Inst. de Fisica

    2009-07-01

    This work presents a dosimetric study of a postal system, to be developed for measurements of brachytherapy. It was projected a PMMA phantom with orifices for insertion of the high dose {sup 192}Ir source and the T L dosemeters. The system was characterized with using of Monte Carlo simulations, using the dosimetric magnitudes defined at the T G-43 of AAPM, as function of radial dose g(f)

  5. Development of Necessary Technology for Safety Grade I and C System

    International Nuclear Information System (INIS)

    Lee, Dong Young; Jang, Tong Il; Kim, Jung Tack

    2010-08-01

    Through KNICS and Nu-Tech 2012, a MMIS(Man-Machine Interface System) package for nuclear plants was localized and is expected to be applied to SUN 1,2 plants. This study is aimed to support the application of the MMIS package including the following technologies that meet strengthened regulation requirements and enhanced utility's performance requirements to nuclear plants. - Dedication to safety-grade computers - The broadband communication network for safety information - Application of the automatic test for safety systems - Application of programmable logic controllers to nuclear plant

  6. Development of a cost-effective machine vision system for in-field sorting and grading of apples: Fruit orientation and size estimation

    Science.gov (United States)

    The objective of this research was to develop an in-field apple presorting and grading system to separate undersized and defective fruit from fresh market-grade apples. To achieve this goal, a cost-effective machine vision inspection prototype was built, which consisted of a low-cost color camera, L...

  7. The Effect of Arabism of Romanic Alphabets on the Development of 9th Grade English as a Foreign Language Students' Writing Skills at Secondary School Level

    Science.gov (United States)

    Zuhair, Ahmad

    2015-01-01

    This paper aims at investigating the effect of Arabization of Romanic Alphabets on the development of 9th Grade English as a Foreign Language students' composition writing skills at secondary school level. This experimental study includes 25 secondary school students in their 9th Grade in which English is taught as a foreign language at…

  8. Modifiable risk factors for acute skin toxicity in adjuvant breast radiotherapy: Dosimetric analysis and review of the literature.

    Science.gov (United States)

    Keenan, Lorna G; Lavan, Naomi; Dunne, Mary; McArdle, Orla

    2018-03-23

    Acute skin toxicity in adjuvant breast radiation can be reduced with modern radiotherapy (RT) techniques. However, having reviewed the literature, we found no dosimetric constraint for acute skin toxicity that would be applicable to modern RT planning. This study aimed to identify dosimetric factors that are associated with higher rates of acute skin toxicity. A retrospective review was carried out including women who received adjuvant forward-planned intensity-modulated radiotherapy (IMRT) after breast-conserving surgery. Acute skin toxicity grade was prospectively recorded. A total of 131 patients were analyzed. On multivariate analysis, the V105% > 30 cc (p = 0.013) and the use of conventional fractionation (CF) (p = 0.001) were statistically significant for acute skin toxicity. On literature review, current quantitative dosimetric parameters that have shown statistical significance include a V107% > 3 cc in hypofractionation (HF), V107% > 9 cc in CF, treated volume 110% > 5.13%, and V107% > 28.6%. There is little evidence on the predictive value of clinically applicable dosimetric factors in acute skin toxicity. Given the recent improvements in RT planning, we would consider a V107% or a V110% too high a dosimetric value to be useful for the majority of patients. We have shown that a V105% of greater than 30 cc is significantly associated with acute skin toxicity, controlling for other variables. We suggest that this is currently the most useful modifiable parameter available to reduce skin toxicity and is applicable to modern RT planning. We also suggest that consideration be given to hypofractionated schedules to further reduce acute skin toxicity. Copyright © 2018. Published by Elsevier Inc.

  9. Using patient values and preferences to inform the importance of health outcomes in practice guideline development following the GRADE approach.

    Science.gov (United States)

    Zhang, Yuan; Coello, Pablo Alonso; Brożek, Jan; Wiercioch, Wojtek; Etxeandia-Ikobaltzeta, Itziar; Akl, Elie A; Meerpohl, Joerg J; Alhazzani, Waleed; Carrasco-Labra, Alonso; Morgan, Rebecca L; Mustafa, Reem A; Riva, John J; Moore, Ainsley; Yepes-Nuñez, Juan José; Cuello-Garcia, Carlos; AlRayees, Zulfa; Manja, Veena; Falavigna, Maicon; Neumann, Ignacio; Brignardello-Petersen, Romina; Santesso, Nancy; Rochwerg, Bram; Darzi, Andrea; Rojas, Maria Ximena; Adi, Yaser; Bollig, Claudia; Waziry, Reem; Schünemann, Holger J

    2017-05-02

    There are diverse opinions and confusion about defining and including patient values and preferences (i.e. the importance people place on the health outcomes) in the guideline development processes. This article aims to provide an overview of a process for systematically incorporating values and preferences in guideline development. In 2013 and 2014, we followed the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach to adopt, adapt and develop 226 recommendations in 22 guidelines for the Ministry of Health of the Kingdom of Saudi Arabia. To collect context-specific values and preferences for each recommendation, we performed systematic reviews, asked clinical experts to provide feedback according to their clinical experience, and consulted patient representatives. We found several types of studies addressing the importance of outcomes, including those reporting utilities, non-utility measures of health states based on structured questionnaires or scales, and qualitative studies. Guideline panels used the relative importance of outcomes based on values and preferences to weigh the balance of desirable and undesirable consequences of alternative intervention options. However, we found few studies addressing local values and preferences. Currently there are different but no firmly established processes for integrating patient values and preferences in healthcare decision-making of practice guideline development. With GRADE Evidence-to-Decision (EtD) frameworks, we provide an empirical strategy to find and incorporate values and preferences in guidelines by performing systematic reviews and eliciting information from guideline panel members and patient representatives. However, more research and practical guidance are needed on how to search for relevant studies and grey literature, assess the certainty of this evidence, and best summarize and present the findings.

  10. Material development for grade X80 heavy-wall hot induction bends

    International Nuclear Information System (INIS)

    Wang Xu; Xiao Furen; Fu Yanhong; Chen Xiaowei; Liao Bo

    2011-01-01

    Highlights: ► The new material for X80 heavy wall thickness hot induction bend was designed. ► The continuous cooling transformation (CCT) diagrams were determined. ► The steel adapts to manufacture of X80 heavy-wall thickness hot induction bend. ► The optimum manufactural processes were obtained. ► The bending temperature is about 990 °C, and tempering is about 600 °C. - Abstract: A new steel for grade X80 heavy wall thickness hot induction bends was designed based on the chemical compositions of commercial X80 steels in this work. Then, its continuous cooling transformation (CCT) diagram was determined with Gleeble-3500 thermo-mechanical simulator. Furthermore, the effects of heat treatment technology on its microstructure and mechanical property were investigated, and the technology parameters of the heat treatment were optimized. The results show that the acicular ferrite and/or bainite transformations are promoted, the polygonal ferrite and pearlite transformation are restrained, because proper amount of alloying elements were added into the new steel. Therefore, the strength of this new steel is improved markedly, even if the cooling rate is lower, which ensure the higher strength distribution along cross section of the heavy wall thickness. It is significant for the manufacture of grade X80 heavy wall thickness hot induction bends in the second West-to-East gas transportation pipeline project of China.

  11. Effect of blood activity on dosimetric calculations for radiopharmaceuticals

    Science.gov (United States)

    Zvereva, Alexandra; Petoussi-Henss, Nina; Li, Wei Bo; Schlattl, Helmut; Oeh, Uwe; Zankl, Maria; Graner, Frank Philipp; Hoeschen, Christoph; Nekolla, Stephan G.; Parodi, Katia; Schwaiger, Markus

    2016-11-01

    The objective of this work was to investigate the influence of the definition of blood as a distinct source on organ doses, associated with the administration of a novel radiopharmaceutical for positron emission tomography-computed tomography (PET/CT) imaging—(S)-4-(3-18F-fluoropropyl)-L-glutamic acid (18F-FSPG). Personalised pharmacokinetic models were constructed based on clinical PET/CT images from five healthy volunteers and blood samples from four of them. Following an identifiability analysis of the developed compartmental models, person-specific model parameters were estimated using the commercial program SAAM II. Organ doses were calculated in accordance to the formalism promulgated by the Committee on Medical Internal Radiation Dose (MIRD) and the International Commission on Radiological Protection (ICRP) using specific absorbed fractions for photons and electrons previously derived for the ICRP reference adult computational voxel phantoms. Organ doses for two concepts were compared: source organ activities in organs parenchyma with blood as a separate source (concept-1); aggregate activities in perfused source organs without blood as a distinct source (concept-2). Aggregate activities comprise the activities of organs parenchyma and the activity in the regional blood volumes (RBV). Concept-1 resulted in notably higher absorbed doses for most organs, especially non-source organs with substantial blood contents, e.g. lungs (92% maximum difference). Consequently, effective doses increased in concept-1 compared to concept-2 by 3-10%. Not considering the blood as a distinct source region leads to an underestimation of the organ absorbed doses and effective doses. The pronounced influence of the blood even for a radiopharmaceutical with a rapid clearance from the blood, such as 18F-FSPG, suggests that blood should be introduced as a separate compartment in most compartmental pharmacokinetic models and blood should be considered as a distinct source in

  12. Developing a Screening Inventory Reading Test (IRT for the Isfahanian Students of the First to Fifth Grade

    Directory of Open Access Journals (Sweden)

    Bijan Shafiei

    2009-12-01

    Full Text Available Background and aim: Reading is one of the most essential skills in this century. Reading disorders can cause several problems for the person who has reading disorder. Early assessment and diagnosis play an important role in treatment of this disorder. The main purpose of this study was to develope a screening inventory reading test (IRT for first to fifth grade student in Isfahan in order to early diagnosis of reading disorder.Materials and Methods: The test, consisting of 100 words context and four comprehension questions, named Inventory Reading Test (IRT, was evaluated by several speech therapists. It was standardized by testing on one thousand boys and girls, 200 students in every grade, that were selected through a multi-stage random sampling method. Test was performed on two other groups, a normal and a reading-disordered.Results: Scores of reading accuracy and velocity were highly correlated with the test total score. Test reliability was calculated as 0.77 by Cronbach`s alpha measure. There was significant difference between two groups mean score (p=0.01.Conclusion: IRT seems to be an appropriate tool for screening reading disorder of first to fifth grade students.

  13. Gaming geography: Educational games and literacy development in the Grade 4 classroom

    Directory of Open Access Journals (Sweden)

    Heather Lotherington

    2010-07-01

    Full Text Available This paper outlines a case study conducted in two public schools in the greater Toronto area as a complementary component of a multisite experimental study exploring educational game development as a learning activity for motivating and engaging students in curriculum-related literacy activities (Owston et al., 2007. Researchers studied children creating and playing four online board games based on grade 4 geography content, viz., Tic-tac-toe, Trivial Pursuit, Snakes and Ladders, and Mother Goose. The schools shared similar positive orientations to technologically focused learning and good technological resources, but they had different institutional histories of implementing computers in curricular learning. Technological equipment was approached, accessed and utilized quite differently in each class, affecting pedagogical practices and learning experiences. Though improvements to traditional literacy learning were found to be limited to improved logical sentence structure (Owston et al., 2007, game development did allow students to build digital literacy skills, including computer literacy and typing skills. Moreover, the project enabled participating teachers to think about profitably incorporating online board game production in broad-based curricular learning. Résumé :Cet article présente une étude de cas menée dans deux écoles publiques de la grande région de Toronto en complément d’une étude expérimentale multisite visant à explorer la conception de jeux éducatifs en tant qu’activité d’apprentissage pour stimuler la motivation et l’engagement des élèves dans des activités de lecture et d’écriture liées au curriculum (Owston et al., 2007. Les chercheurs ont étudié les enfants lors de la création puis de l’utilisation de quatre jeux de plateau en ligne axés sur la matière de 4e année en géographie. Les élèves ont réalisé une version des jeux de Tic-Tac-Toe, de Quelques arpents de pièges, de Serpents

  14. Analysis of clinical and dosimetric factors associated with severe acute radiation pneumonitis in patients with locally advanced non-small cell lung cancer treated with concurrent chemotherapy and intensity-modulated radiotherapy

    Directory of Open Access Journals (Sweden)

    Xu Bo

    2010-05-01

    Full Text Available Abstract Background To evaluate the association between the clinical, dosimetric factors and severe acute radiation pneumonitis (SARP in patients with locally advanced non-small cell lung cancer (LANSCLC treated with concurrent chemotherapy and intensity-modulated radiotherapy (IMRT. Methods We analyzed 94 LANSCLC patients treated with concurrent chemotherapy and IMRT between May 2005 and September 2006. SARP was defined as greater than or equal 3 side effects and graded according to Common Terminology Criteria for Adverse Events (CTCAE version 3.0. The clinical and dosimetric factors were analyzed. Univariate and multivariate logistic regression analyses were performed to evaluate the relationship between clinical, dosimetric factors and SARP. Results Median follow-up was 10.5 months (range 6.5-24. Of 94 patients, 11 (11.7% developed SARP. Univariate analyses showed that the normal tissue complication probability (NTCP, mean lung dose (MLD, relative volumes of lung receiving more than a threshold dose of 5-60 Gy at increments of 5 Gy (V5-V60, chronic obstructive pulmonary disease (COPD and Forced Expiratory Volume in the first second (FEV1 were associated with SARP (p p = 0.001 and V10 (p = 0.015 were the most significant factors associated with SARP. The incidences of SARP in the group with NTCP > 4.2% and NTCP ≤4.2% were 43.5% and 1.4%, respectively (p 50% were 5.7% and 29.2%, respectively (p Conclusions NTCP value and V10 are the useful indicators for predicting SARP in NSCLC patients treated with concurrent chemotherapy and IMRT.

  15. Roles of Chronic Low-Grade Inflammation in the Development of Ectopic Fat Deposition

    Directory of Open Access Journals (Sweden)

    Lulu Liu

    2014-01-01

    Full Text Available Pattern of fat distribution is a major determinant for metabolic homeostasis. As a depot of energy, the storage of triglycerides in adipose tissue contributes to the normal fat distribution. Decreased capacity of fat storage in adipose tissue may result in ectopic fat deposition in nonadipose tissues such as liver, pancreas, and kidney. As a critical biomarker of metabolic complications, chronic low-grade inflammation may have the ability to affect the process of lipid accumulation and further lead to the disorder of fat distribution. In this review, we have collected the evidence linking inflammation with ectopic fat deposition to get a better understanding of the underlying mechanism, which may provide us with novel therapeutic strategies for metabolic disorders.

  16. The Development of Media Literacy among Grade Five Teachers and Students - A Case Study

    Directory of Open Access Journals (Sweden)

    Rachel McCabe

    2008-03-01

    Full Text Available This is the first of two articles about a study of the implementation of a media literacy curriculum project in three inner city school Grade 5's in Montreal. The authors describe what the teachers and students learned about two key Media Literacy concepts: the media construct reality and audiences negotiate the meanings of media texts. The teaching featured the use of Internet and computer technology. Their findings suggest that it is possible to teach elementary students to read media critically and raises some issues that merit further investigation: the ideology of positivism that permeates the use of technology in education; the training of media education teachers; and the factors that characterize effective media education pedagogy.

  17. Initial Report of a Prospective Dosimetric and Clinical Feasibility Trial Demonstrates the Potential of Protons to Increase the Therapeutic Ratio in Breast Cancer Compared With Photons

    Energy Technology Data Exchange (ETDEWEB)

    Bradley, Julie A., E-mail: jbradley@floridaproton.org; Dagan, Roi; Ho, Meng Wei; Rutenberg, Michael; Morris, Christopher G.; Li, Zuofeng; Mendenhall, Nancy P.

    2016-05-01

    Purpose: To compare dosimetric endpoints between proton therapy (PT) and conventional radiation and determine the feasibility of PT for regional nodal irradiation (RNI) in women with breast cancer. Methods and Materials: From 2012 to 2014, 18 women (stage IIA-IIIB) requiring RNI prospectively enrolled on a pilot study. Median age was 51.8 years (range, 42-73 years). The cohort included breast-conserving therapy (BCT) and mastectomy patients and right- and left-sided cancers. Treatment targets and organs at risk were delineated on computed tomography scans, and PT and conventional plans were developed. Toxicity was prospectively recorded using Common Terminology Criteria for Adverse Events version 4.0. A Wilcoxon signed-rank sum test compared the dose-volume parameters. The primary endpoint was a reduction in cardiac V5. Results: Median follow-up was 20 months (range, 2-31 months). For all patients, the PT plan better met the dosimetric goals and was used for treatment. Proton therapy alone was used for 10 patients (9 postmastectomy, 1 after BCT) and combined proton–photon in 8 (6 BCT, 2 postmastectomy with immediate expander reconstruction). Proton therapy improved coverage of level 2 axilla (P=.0005). Adequate coverage of internal mammary nodes was consistently achieved with PT (median D95, 50.3 Gy; range, 46.6-52.1 Gy) but not with conventional radiation therapy (median D95, 48.2 Gy; range, 40.8-55 Gy; P=.0005). Median cardiac V5 was 0.6% with PT and 16.3% with conventional radiation (P<.0001). Median ipsilateral lung V5 and V20 were improved with PT (median V5 35.3% vs 60.5% [P<.0001]; and median V20, 21.6% vs 35.5% [P<.0001]). Grade 3 dermatitis developed in 4 patients (22%), which was the only grade 3 toxicity. No grade 4+ toxicities developed. Conclusion: Proton therapy for RNI after mastectomy or BCT significantly improves cardiac dose, especially for left-sided patients, and lung V5 and V20 in all patients without excessive acute toxicity

  18. Dosimetric comparison of intensity-modulated, conformal, and four-field pelvic radiotherapy boost plans for gynecologic cancer: a retrospective planning study

    International Nuclear Information System (INIS)

    Chan, Philip; Yeo, Inhwan; Perkins, Gregory; Fyles, Anthony; Milosevic, Michael

    2006-01-01

    To evaluate intensity-modulated radiation therapy (IMRT) as an alternative to conformal radiotherapy (CRT) or 4-field box boost (4FB) in women with gynecologic malignancies who are unsuitable for brachytherapy for technical or medical reasons. Dosimetric and toxicity information was analyzed for 12 patients with cervical (8), endometrial (2) or vaginal (2) cancer previously treated with external beam pelvic radiotherapy and a CRT boost. Optimized IMRT boost treatment plans were then developed for each of the 12 patients and compared to CRT and 4FB plans. The plans were compared in terms of dose conformality and critical normal tissue avoidance. The median planning target volume (PTV) was 151 cm 3 (range 58–512 cm 3 ). The median overlap of the contoured rectum with the PTV was 15 (1–56) %, and 11 (4–35) % for the bladder. Two of the 12 patients, both with large PTVs and large overlap of the contoured rectum and PTV, developed grade 3 rectal bleeding. The dose conformity was significantly improved with IMRT over CRT and 4FB (p ≤ 0.001 for both). IMRT also yielded an overall improvement in the rectal and bladder dose-volume distributions relative to CRT and 4FB. The volume of rectum that received the highest doses (>66% of the prescription) was reduced by 22% (p < 0.001) with IMRT relative to 4FB, and the bladder volume was reduced by 19% (p < 0.001). This was at the expense of an increase in the volume of these organs receiving doses in the lowest range (<33%). These results indicate that IMRT can improve target coverage and reduce dose to critical structures in gynecologic patients receiving an external beam radiotherapy boost. This dosimetric advantage will be integrated with other patient and treatment-specific factors, particularly internal tumor movement during fractionated radiotherapy, in the context of a future image-guided radiation therapy study

  19. CT prediction of the Fuhrman grade of clear cell renal cell carcinoma (RCC): towards the development of computer-assisted diagnostic method.

    Science.gov (United States)

    Huhdanpaa, Hannu; Hwang, Darryl; Cen, Steven; Quinn, Brian; Nayyar, Megha; Zhang, Xuejun; Chen, Frank; Desai, Bhushan; Liang, Gangning; Gill, Inderbir; Duddalwar, Vinay

    2015-10-01

    There are distinct quantifiable features characterizing renal cell carcinomas on contrast-enhanced CT examinations, such as peak tumor enhancement, tumor heterogeneity, and percent contrast washout. While qualitative visual impressions often suffice for diagnosis, quantitative metrics if developed and validated can add to the information available from standard of care diagnostic imaging. The purpose of this study is to assess the use of quantitative enhancement metrics in predicting the Fuhrman grade of clear cell RCC. 65 multiphase CT examinations with clear cell RCCs were utilized, 44 tumors with Fuhrman grades 1 or 2 and 21 tumors with grades 3 or 4. After tumor segmentation, the following data were extracted: histogram analysis of voxel-based whole lesion attenuation in each phase, enhancement and washout using mean, median, skewness, kurtosis, standard deviation, and interquartile range. Statistically significant difference was observed in 4 measured parameters between grades 1-2 and grades 3-4: interquartile range of nephrographic attenuation values, standard deviation of absolute enhancement, as well as interquartile range and standard deviation of residual nephrographic enhancement. Interquartile range of nephrographic attenuation values was 292.86 HU for grades 1-2 and 241.19 HU for grades 3-4 (p value 0.02). Standard deviation of absolute enhancement was 41.26 HU for grades 1-2 and 34.66 HU for grades 3-4 (p value 0.03). Interquartile range was 297.12 HU for residual nephrographic enhancement for grades 1-2 and 235.57 HU for grades 3-4 (p value 0.02), and standard deviation of the same was 42.45 HU for grades 1-2 and 37.11 for grades 3-4 (p value 0.04). Our results indicate that absolute enhancement is more heterogeneous for lower grade tumors and that attenuation and residual enhancement in nephrographic phase is more heterogeneous for lower grade tumors. This represents an important step in devising a predictive non-invasive model to predict the

  20. PROGNOSYS AND ANALYSIS OF DOSIMETRIC SITUATION AFTER EMERGENCY ATMOSPHERIC RELEASE OF NPP IN UKRAINE

    Directory of Open Access Journals (Sweden)

    Iu. V. Bonchuk

    2009-01-01

    Full Text Available The system for the operative analysis of dosimetric situation after radiation emergencies at nuclear power plants in Ukraine (KADO is developed for decision making support. Emergency release in KADO is modelled as sequence of the discrete elements which are emitted after small time intervals that allows to take into account in calculations heterogeneity of distribution of pollution in a released cloud. Calculated predicted and avertable doses are the base information for justification of emergency and urgent countermeasures.

  1. Thermoluminescent dosimetric properties of Descalvado sand

    International Nuclear Information System (INIS)

    Teixeira, M.I.; Caldas, L.V.E.

    2006-01-01

    Sand samples proceeding from Descalvado, Sao Paulo, were studied with regard to their dosimetric properties using the thermoluminescence technique (TL) for high doses. These sand samples present steady physical and chemical characteristics to the end items, and they are used in the glass industry and for casting. The TL curves of the samples were obtained after an irradiation at the Gamma-Cell system ( 60 Co), of IPEN. The glow curves present two peaks at 80 C and 220 C approximately. Calibration curves were obtained for doses between 50 Gy and 5 kGy. The results indicate that the sand samples can be used for high-doses dosimetry in several areas of applications of ionizing radiation. (Author)

  2. Thermoluminescent dosimetric properties of Descalvado sand

    Energy Technology Data Exchange (ETDEWEB)

    Teixeira, M.I.; Caldas, L.V.E

    2006-07-01

    Sand samples proceeding from Descalvado, Sao Paulo, were studied with regard to their dosimetric properties using the thermoluminescence technique (TL) for high doses. These sand samples present steady physical and chemical characteristics to the end items, and they are used in the glass industry and for casting. The TL curves of the samples were obtained after an irradiation at the Gamma-Cell system ({sup 60} Co), of IPEN. The glow curves present two peaks at 80 C and 220 C approximately. Calibration curves were obtained for doses between 50 Gy and 5 kGy. The results indicate that the sand samples can be used for high-doses dosimetry in several areas of applications of ionizing radiation. (Author)

  3. A national dosimetric audit of IMRT

    International Nuclear Information System (INIS)

    Budgell, Geoff; Berresford, Joe; Trainer, Michael; Bradshaw, Ellie; Sharpe, Peter; Williams, Peter

    2011-01-01

    Background and purpose: A dosimetric audit of IMRT has been carried out within the UK between June 2009 and March 2010 in order to provide an independent check of safe implementation and to identify problems in the modelling and delivery of IMRT. Methods and materials: A mail based audit involving film and alanine dosimeters was utilized. Measurements were made for each individual field in an IMRT plan isocentrically in a flat water-equivalent phantom at a depth of 5 cm. The films and alanine dosimeters were processed and analysed centrally; additional ion chamber measurements were made by each participating centre. Results: 57 of 62 centres participated, with a total of 78 plans submitted. For the film measurements, all 176 fields from the less complex IMRT plans (including prostate and breast plans) achieved over 95% pixels passing a gamma criterion of 3%/3 mm within the 20% isodose. For the more complex IMRT plans (mainly head and neck) 8/245 fields (3.3%) achieved less than 95% pixels passing a 4%/4 mm gamma criterion. Of the alanine measurements, 4/78 (5.1%) of the measurements differed by >5% from the dose predicted by the treatment planning system. Three of these were large deviations of -77.1%, -29.1% and 14.1% respectively. Excluding the three measurements outside 10%, the mean difference was 0.05% with a standard deviation of 1.5%. The out of tolerance results have been subjected to further investigations. Conclusions: A dosimetric audit has been successfully carried out of IMRT implementation by over 90% of UK radiotherapy departments. The audit shows that modelling and delivery of IMRT is accurate, suggesting that the implementation of IMRT has been carried out safely.

  4. Dosimetric evaluation of proton stereotactic radiosurgery

    International Nuclear Information System (INIS)

    Min, Byung Jun; Shin, Dong Ho; Yoo, Seung Hoon; Jeong, Hojin; Lee, Se Byeong

    2011-01-01

    Surgical excision, conventional external radiotherapy, and chemotherapy could prolong survival in patients with small intracranial tumors. However, surgical excision for meningiomas located in the region of the base of skull or re-resection is often difficult. Moreover, treatment is needed for patients with recurrent tumors or postoperative residual tumors. Conventional external radiotherapy is popular and has significantly increased for treating brain tumors. Stereotactic radiosurgery is an effective alternative treatment technique to microsurgical resection such as benign brain tumor or vestibular Schwannomas. In general, the dose to OAR of 3D conformal plan is lower than that of conformal arc and dynamic conformal arc plans. However, any of OARs was not reached to tolerance dose. Although mean dose of the healthy brain tissue for 3D conformal plan was slightly higher than that of arc plans, the doses of the healthy brain tissue at V10 and V20 were significantly low for dynamic conformal arc plan. The dosimetric differences were the greatest at lower doses. In contrast, 3D conformal plan was better spare at higher doses. In this study, a dosimetric evaluation of proton stereotactic radiosurgery for brain lesion tumors was using fixed and arc beams. A brass block fitted to the PTV structure was modeled for dynamic conformal collimator. Although all treatment plans offer a very good coverage of the PTV, we found that proton arc plans had significantly better conformity to the PTV than static 3D conformal plan. The V20 dose of normal brain for dynamic conformal arc therapy is dramatically reduced compare to those for other therapy techniques.

  5. On Development and Wear Behavior of Microwave-Processed Functionally Graded Ni-SiC Clads on SS-304 Substrate

    Science.gov (United States)

    Kaushal, Sarbjeet; Gupta, Dheeraj; Bhowmick, Hiralal

    2018-02-01

    In this study, the functionally graded Ni-SiC claddings with gradual change in SiC contents were deposited on SS-304 substrate using microwave hybrid heating technique. Experimental trials were carried out inside a multimode domestic microwave device at 2.45 GHz and 900 W. The optimal exposure time of 900 W microwave power was varied with compositional gradient, and it was from 300 to 360 s. The developed functionally graded clad (FGC) was characterized by SEM/EDS, XRD and Vicker's micro-hardness. Microstructural analysis results revealed that the FGC of approximately 2 mm thickness was developed and was free from any type of interfacial cracks and visible porosity. The maximum micro-hardness was at the top FGC layer, and its value was 1025 ± 30 HV. Three types of single-layer claddings were also developed to compare the tribological behavior of FGC. FGC exhibited 32 and 1.2 times more wear resistance than SS-304 substrate and Ni + 30% SiC layer, respectively. In the case of FGC, wear mainly occurs due to debonding of carbide particles from the matrix, while plastic deformation and strong abrasion are responsible for material loss in the case of the SS-304 substrate.

  6. Patient-specific dosimetric endpoints based treatment plan quality control in radiotherapy

    International Nuclear Information System (INIS)

    Song, Ting; Zhou, Linghong; Staub, David; Chen, Mingli; Lu, Weiguo; Tian, Zhen; Jia, Xun; Li, Yongbao; Jiang, Steve B; Gu, Xuejun

    2015-01-01

    In intensity modulated radiotherapy (IMRT), the optimal plan for each patient is specific due to unique patient anatomy. To achieve such a plan, patient-specific dosimetric goals reflecting each patient’s unique anatomy should be defined and adopted in the treatment planning procedure for plan quality control. This study is to develop such a personalized treatment plan quality control tool by predicting patient-specific dosimetric endpoints (DEs). The incorporation of patient specific DEs is realized by a multi-OAR geometry-dosimetry model, capable of predicting optimal DEs based on the individual patient’s geometry. The overall quality of a treatment plan is then judged with a numerical treatment plan quality indicator and characterized as optimal or suboptimal. Taking advantage of clinically available prostate volumetric modulated arc therapy (VMAT) treatment plans, we built and evaluated our proposed plan quality control tool. Using our developed tool, six of twenty evaluated plans were identified as sub-optimal plans. After plan re-optimization, these suboptimal plans achieved better OAR dose sparing without sacrificing the PTV coverage, and the dosimetric endpoints of the re-optimized plans agreed well with the model predicted values, which validate the predictability of the proposed tool. In conclusion, the developed tool is able to accurately predict optimally achievable DEs of multiple OARs, identify suboptimal plans, and guide plan optimization. It is a useful tool for achieving patient-specific treatment plan quality control. (paper)

  7. Development of a Large-Format Science-Grade CMOS Active Pixel Sensor, for Extreme Ultra Violet Spectroscopy and Imaging in Space Science

    National Research Council Canada - National Science Library

    Waltham, N. R; Prydderch, M; Mapson-Menard, H; Morrissey, Q; Turchetta, R; Pool, P; Harris, A

    2005-01-01

    We describe our programme to develop a large-format science-grade CMOS active pixel sensor for future space science missions, and in particular an extreme ultra-violet spectrograph for solar physics...

  8. Determination of Absorbed Dose Using a Dosimetric Film

    International Nuclear Information System (INIS)

    Scarlat, F.; Scarisoreanu, A.; Oane, M.; Badita, E.; Mitru, E.

    2009-01-01

    This paper presents the absorbed dose measurements by means of the irradiated dosimetric reference films. The dose distributions were made by MULTIDATA film densitometer using RTD-4 software, in INFLPR Linear Accelerator Department

  9. Genome Editing of Food-Grade Lactobacilli To Develop Therapeutic Probiotics.

    Science.gov (United States)

    van Pijkeren, Jan-Peter; Barrangou, Rodolphe

    2017-09-01

    Lactic acid bacteria have been used historically for food manufacturing mainly to ensure preservation via fermentation. More recently, lactic acid bacteria have been exploited to promote human health, and many strains serve as industrial workhorses. Recent advances in microbiology and molecular biology have contributed to understanding the genetic basis of many of their functional attributes. These include dissection of biochemical processes that drive food fermentation, and identification and characterization of health-promoting features that positively impact the composition and roles of microbiomes in human health. Recently, the advent of clustered regularly interspaced short palindromic repeat (CRISPR)-based technologies has revolutionized our ability to manipulate genomes, and we are on the cusp of a broad-scale genome editing revolution. Here, we discuss recent advances in genetic alteration of food-grade bacteria, with a focus on CRISPR-associated enzyme genome editing, single-stranded DNA recombineering, and the modification of bacteriophages. These tools open new avenues for the genesis of next-generation biotherapeutic agents with improved genotypes and enhanced health-promoting functional features.

  10. Modeling platinum sensitive and resistant high grade serous ovarian cancer: development and applications of experimental systems

    Directory of Open Access Journals (Sweden)

    Paula eCunnea

    2014-04-01

    Full Text Available High grade serous ovarian cancer remains the most common sub-type of ovarian cancer and, characterized by high degrees of genomic instability and heterogeneity, is typified by a transition from early response to acquired resistance to platinum based chemotherapy. Conventional models for the study of ovarian cancer have been largely limited to a set of relatively poorly characterized immortalized cell lines and recent studies have called into question the validity of some of these as reliable models. Here we review new approaches and models systems which take into account advances in our understanding of ovarian cancer biology and advances in the technology available for their generation and study. We discuss primary cell models, 2D, 3D and organotypic models, and paired sample approaches that capture the evolution of chemotherapy failure within single cases. We also overview new methods for non-invasive collection of representative tumor material from blood samples. Adoption of such methods and models will improve the quality and clinical relevance of ovarian cancer research.

  11. On the development of radiation tolerant surveillance camera from consumer-grade components

    Directory of Open Access Journals (Sweden)

    Klemen Ambrožič

    2017-01-01

    Full Text Available In this paper an overview on the process of designing a radiation tolerant surveillance camera from consumer grade components and commercially available particle shielding materials is given. This involves utilization of Monte-Carlo particle transport code MCNP6 and ENDF/B-VII.0 nuclear data libraries, as well as testing the physical electrical systems against γ radiation, utilizing JSI TRIGA mk. II fuel elements as a γ-ray sources. A new, aluminum, 20 cm × 20 cm × 30 cm irradiation facility with electrical power and signal wire guide-tube to the reactor platform, was designed and constructed and used for irradiation of large electronic and optical components assemblies with activated fuel elements. Electronic components to be used in the camera were tested against γ-radiation in an independent manner, to determine their radiation tolerance. Several camera designs were proposed and simulated using MCNP, to determine incident particle and dose attenuation factors. Data obtained from the measurements and MCNP simulations will be used to finalize the design of 3 surveillance camera models, with different radiation tolerances.

  12. Developing clinical practice guidelines: types of evidence and outcomes; values and economics, synthesis, grading, and presentation and deriving recommendations.

    Science.gov (United States)

    Woolf, Steven; Schünemann, Holger J; Eccles, Martin P; Grimshaw, Jeremy M; Shekelle, Paul

    2012-07-04

    Clinical practice guidelines are one of the foundations of efforts to improve healthcare. In 1999, we authored a paper about methods to develop guidelines. Since it was published, the methods of guideline development have progressed both in terms of methods and necessary procedures and the context for guideline development has changed with the emergence of guideline clearinghouses and large scale guideline production organisations (such as the UK National Institute for Health and Clinical Excellence). It therefore seems timely to, in a series of three articles, update and extend our earlier paper. In this second paper, we discuss issues of identifying and synthesizing evidence: deciding what type of evidence and outcomes to include in guidelines; integrating values into a guideline; incorporating economic considerations; synthesis, grading, and presentation of evidence; and moving from evidence to recommendations.

  13. Dosimetric characteristics of biological effect of sulfur-35

    International Nuclear Information System (INIS)

    Borisova, V.V.

    1990-01-01

    Experimental materials related to evaluation of dosimetric characteristics of sulfur-35 are presented. Hemogenic organs are subjected to greatest influence especially in the first hours after radionuclide entry into the organism. Comparison is made of absorbed doses in blood with observed blastomogen effect of hemogenic organs. It is noted, that quantitative evaluation of relative biological efficiency of low energy beta-emitters should be performed with account of dosimetric peculiarities of the nuclides mentioned above. 10 refs.; 3 tabs

  14. Historical accounts of the radiation protection- Dosimetric surveillance of L. Berard Center personnel from 1960 to 1988

    International Nuclear Information System (INIS)

    Paoletti, H.

    1990-09-01

    In this thesis, the author describes the discovery of radiations, their first medical applications and first accidents that have been in the beginning of radiation protection and of its development. The author explains how the dosimetric monitoring has been organized at L. Berard Centre in Lyon (France)

  15. Analysis of clinical and dosimetric factors associated with change in renal function in patients with gastrointestinal malignancies after chemoradiation to the abdomen.

    Science.gov (United States)

    May, Kilian Salerno; Khushalani, Nikhil I; Chandrasekhar, Rameela; Wilding, Gregory E; Iyer, Renuka V; Ma, Wen W; Flaherty, Leayn; Russo, Richard C; Fakih, Marwan; Kuvshinoff, Boris W; Gibbs, John F; Javle, Milind M; Yang, Gary Y

    2010-03-15

    To analyze clinical and dosimetric factors associated with change in renal function in patients with gastrointestinal malignancies after chemoradiation to the abdomen. A retrospective review of 164 patients with gastrointestinal malignancies treated between 2002 and 2007 was conducted to evaluate change in renal function after concurrent chemotherapy and three-dimensional conformal abdominal radiotherapy (RT). Laboratory and biochemical endpoints were determined before RT and after RT at 6-month intervals. Factors assessed included smoking, diabetes, hypertension, blood urea nitrogen, creatinine, creatinine clearance (CrCl), chemotherapy, and dose-volume parameters. Renal toxicity was assessed by decrease in CrCl and scored using the Radiation Therapy Oncology Group/European Organization for Research and Treatment of Cancer late radiation morbidity scoring schema. Of 164 patients, 63 had clinical and dosimetric data available. Median follow-up was 17.5 months. Creatinine clearance declined from 98.46 mL/min before RT to 74.20 mL/min one year after chemoradiation (p kidney dose were significantly associated with development of Grade > or =2 renal complications at 1 year after chemoradiation (p = 0.0025, 0.0170, and 0.0095, respectively). We observed correlation between pre-RT CrCl, V(10), and mean kidney dose and decline in CrCl 1 year after chemoradiation. These observations can assist in treatment planning and renal dose constraints in patients receiving chemotherapy and abdominal RT and may help identify patients at increased risk for renal complications. Published by Elsevier Inc.

  16. Analysis of Clinical and Dosimetric Factors Associated With Change in Renal Function in Patients With Gastrointestinal Malignancies After Chemoradiation to the Abdomen

    International Nuclear Information System (INIS)

    May, Kilian Salerno; Khushalani, Nikhil I.; Chandrasekhar, Rameela; Wilding, Gregory E.; Iyer, Renuka V.; Ma, Wen W.; Flaherty, Leayn; Russo, Richard C. C.; Fakih, Marwan; Kuvshinoff, Boris W.; Gibbs, John F.; Javle, Milind M.; Yang, Gary Y.

    2010-01-01

    Purpose: To analyze clinical and dosimetric factors associated with change in renal function in patients with gastrointestinal malignancies after chemoradiation to the abdomen. Methods and Materials: A retrospective review of 164 patients with gastrointestinal malignancies treated between 2002 and 2007 was conducted to evaluate change in renal function after concurrent chemotherapy and three-dimensional conformal abdominal radiotherapy (RT). Laboratory and biochemical endpoints were determined before RT and after RT at 6-month intervals. Factors assessed included smoking, diabetes, hypertension, blood urea nitrogen, creatinine, creatinine clearance (CrCl), chemotherapy, and dose-volume parameters. Renal toxicity was assessed by decrease in CrCl and scored using the Radiation Therapy Oncology Group/European Organization for Research and Treatment of Cancer late radiation morbidity scoring schema. Results: Of 164 patients, 63 had clinical and dosimetric data available. Median follow-up was 17.5 months. Creatinine clearance declined from 98.46 mL/min before RT to 74.20 mL/min one year after chemoradiation (p 10 ), and mean kidney dose were significantly associated with development of Grade ≥2 renal complications at 1 year after chemoradiation (p = 0.0025, 0.0170, and 0.0095, respectively). Conclusions: We observed correlation between pre-RT CrCl, V 10 , and mean kidney dose and decline in CrCl 1 year after chemoradiation. These observations can assist in treatment planning and renal dose constraints in patients receiving chemotherapy and abdominal RT and may help identify patients at increased risk for renal complications.

  17. Development of Functionally Graded Materials for Manufacturing Tools and Dies and Industrial Processing Equipment

    Energy Technology Data Exchange (ETDEWEB)

    Lherbier, Louis, W.; Novotnak, David, J.; Herling, Darrell, R.; Sears, James, W.

    2009-03-23

    Hot forming processes such as forging, die casting and glass forming require tooling that is subjected to high temperatures during the manufacturing of components. Current tooling is adversely affected by prolonged exposure at high temperatures. Initial studies were conducted to determine the root cause of tool failures in a number of applications. Results show that tool failures vary and depend on the operating environment under which they are used. Major root cause failures include (1) thermal softening, (2) fatigue and (3) tool erosion, all of which are affected by process boundary conditions such as lubrication, cooling, process speed, etc. While thermal management is a key to addressing tooling failures, it was clear that new tooling materials with superior high temperature strength could provide improved manufacturing efficiencies. These efficiencies are based on the use of functionally graded materials (FGM), a new subset of hybrid tools with customizable properties that can be fabricated using advanced powder metallurgy manufacturing technologies. Modeling studies of the various hot forming processes helped identify the effect of key variables such as stress, temperature and cooling rate and aid in the selection of tooling materials for specific applications. To address the problem of high temperature strength, several advanced powder metallurgy nickel and cobalt based alloys were selected for evaluation. These materials were manufactured into tooling using two relatively new consolidation processes. One process involved laser powder deposition (LPD) and the second involved a solid state dynamic powder consolidation (SSDPC) process. These processes made possible functionally graded materials (FGM) that resulted in shaped tooling that was monolithic, bi-metallic or substrate coated. Manufacturing of tooling with these processes was determined to be robust and consistent for a variety of materials. Prototype and production testing of FGM tooling showed the

  18. Conventional Versus Automated Implantation of Loose Seeds in Prostate Brachytherapy: Analysis of Dosimetric and Clinical Results

    Energy Technology Data Exchange (ETDEWEB)

    Genebes, Caroline, E-mail: genebes.caroline@claudiusregaud.fr [Radiation Oncology Department, Institut Claudius Regaud, Toulouse (France); Filleron, Thomas; Graff, Pierre [Radiation Oncology Department, Institut Claudius Regaud, Toulouse (France); Jonca, Frédéric [Department of Urology, Clinique Ambroise Paré, Toulouse (France); Huyghe, Eric; Thoulouzan, Matthieu; Soulie, Michel; Malavaud, Bernard [Department of Urology and Andrology, CHU Rangueil, Toulouse (France); Aziza, Richard; Brun, Thomas; Delannes, Martine; Bachaud, Jean-Marc [Radiation Oncology Department, Institut Claudius Regaud, Toulouse (France)

    2013-11-15

    Purpose: To review the clinical outcome of I-125 permanent prostate brachytherapy (PPB) for low-risk and intermediate-risk prostate cancer and to compare 2 techniques of loose-seed implantation. Methods and Materials: 574 consecutive patients underwent I-125 PPB for low-risk and intermediate-risk prostate cancer between 2000 and 2008. Two successive techniques were used: conventional implantation from 2000 to 2004 and automated implantation (Nucletron, FIRST system) from 2004 to 2008. Dosimetric and biochemical recurrence-free (bNED) survival results were reported and compared for the 2 techniques. Univariate and multivariate analysis researched independent predictors for bNED survival. Results: 419 (73%) and 155 (27%) patients with low-risk and intermediate-risk disease, respectively, were treated (median follow-up time, 69.3 months). The 60-month bNED survival rates were 95.2% and 85.7%, respectively, for patients with low-risk and intermediate-risk disease (P=.04). In univariate analysis, patients treated with automated implantation had worse bNED survival rates than did those treated with conventional implantation (P<.0001). By day 30, patients treated with automated implantation showed lower values of dose delivered to 90% of prostate volume (D90) and volume of prostate receiving 100% of prescribed dose (V100). In multivariate analysis, implantation technique, Gleason score, and V100 on day 30 were independent predictors of recurrence-free status. Grade 3 urethritis and urinary incontinence were observed in 2.6% and 1.6% of the cohort, respectively, with no significant differences between the 2 techniques. No grade 3 proctitis was observed. Conclusion: Satisfactory 60-month bNED survival rates (93.1%) and acceptable toxicity (grade 3 urethritis <3%) were achieved by loose-seed implantation. Automated implantation was associated with worse dosimetric and bNED survival outcomes.

  19. Conventional Versus Automated Implantation of Loose Seeds in Prostate Brachytherapy: Analysis of Dosimetric and Clinical Results

    International Nuclear Information System (INIS)

    Genebes, Caroline; Filleron, Thomas; Graff, Pierre; Jonca, Frédéric; Huyghe, Eric; Thoulouzan, Matthieu; Soulie, Michel; Malavaud, Bernard; Aziza, Richard; Brun, Thomas; Delannes, Martine; Bachaud, Jean-Marc

    2013-01-01

    Purpose: To review the clinical outcome of I-125 permanent prostate brachytherapy (PPB) for low-risk and intermediate-risk prostate cancer and to compare 2 techniques of loose-seed implantation. Methods and Materials: 574 consecutive patients underwent I-125 PPB for low-risk and intermediate-risk prostate cancer between 2000 and 2008. Two successive techniques were used: conventional implantation from 2000 to 2004 and automated implantation (Nucletron, FIRST system) from 2004 to 2008. Dosimetric and biochemical recurrence-free (bNED) survival results were reported and compared for the 2 techniques. Univariate and multivariate analysis researched independent predictors for bNED survival. Results: 419 (73%) and 155 (27%) patients with low-risk and intermediate-risk disease, respectively, were treated (median follow-up time, 69.3 months). The 60-month bNED survival rates were 95.2% and 85.7%, respectively, for patients with low-risk and intermediate-risk disease (P=.04). In univariate analysis, patients treated with automated implantation had worse bNED survival rates than did those treated with conventional implantation (P<.0001). By day 30, patients treated with automated implantation showed lower values of dose delivered to 90% of prostate volume (D90) and volume of prostate receiving 100% of prescribed dose (V100). In multivariate analysis, implantation technique, Gleason score, and V100 on day 30 were independent predictors of recurrence-free status. Grade 3 urethritis and urinary incontinence were observed in 2.6% and 1.6% of the cohort, respectively, with no significant differences between the 2 techniques. No grade 3 proctitis was observed. Conclusion: Satisfactory 60-month bNED survival rates (93.1%) and acceptable toxicity (grade 3 urethritis <3%) were achieved by loose-seed implantation. Automated implantation was associated with worse dosimetric and bNED survival outcomes

  20. Dosimetric predictors of radiation-induced pericardial effusion in esophageal cancer

    Energy Technology Data Exchange (ETDEWEB)

    Ogino, Ichiro; Watanabe, Shigenobu [Yokohama City University Medical Center, Department of Radiation Oncology, Minami-ku, Yokohama, Kanagawa-prefecture (Japan); Sakamaki, Kentaro [Yokohama City University, Department of Biostatistics, Yokohama City University, Yokohama (Japan); Ogino, Yuka [Tokyo Institute of Technology, Department of Systems and Control Engineering, Tokyo (Japan); Kunisaki, Chikara [Yokohama City University Medical Center, Department of Surgery, Gastroenterological Center, Yokohama (Japan); Kimura, Kazuo [Yokohama City University Medical Center, Division of Cardiology, Yokohama (Japan)

    2017-07-15

    To evaluate the dose-volume parameters of the pericardium and heart in order to reduce the risk of radiation-induced pericardial effusion (PE) and symptomatic PE (SPE) in esophageal cancer patients treated with concurrent chemoradiotherapy. In 86 of 303 esophageal cancer patients, follow-up CT was obtained at least 24 months after concurrent chemoradiotherapy. Correlations between clinical factors, including risk factors for cardiac disease, dosimetric factors, and the incidence of PE and SPE after radiotherapy were analyzed using Cox proportional hazard regression analysis. Significant dosimetric factors with the highest hazard ratios were investigated using zones separated according to their distance from esophagus. PE developed in 49 patients. Univariate analysis showed the mean heart dose, heart V{sub 5}-V{sub 55}, mean pericardium dose, and pericardium V{sub 5}-V{sub 50} to all significantly affect the incidence of PE. Additionally, body surface area was correlated with the incidence of PE in multivariate analysis. Grade 3 and 4 SPE developed in 5 patients. The pericardium V{sub 50} and pericardium D{sub 10} significantly affected the incidence of SPE. The pericardium V{sub 50} in patients with SPE ranged from 17.1 to 21.7%. Factors affecting the incidence of SPE were the V{sub 50} of the pericardium zones within 3 cm and 4 cm of the esophagus. A wide range of radiation doses to the heart and pericardium were related to the incidence of PE. A pericardium V{sub 50} ≤ 17% is important to avoid symptomatic PE in esophageal cancer patients treated with concurrent chemoradiotherapy. (orig.) [German] Beurteilung der Dosis-Volumen-Parameter fuer Perikard und Herz zur Risikoreduzierung eines strahleninduzierten Perikardergusses (PE) und eines symptomatischen PE (SPE) bei mit kombinierter Strahlenchemotherapie behandelten Speiseroehrenkrebspatienten. Bei 86 von 303 Speiseroehrenkrebspatienten wurde mindestens 24 Monate nach der Strahlenchemotherapie ein Kontroll

  1. Development of Integrated Natural Science Teaching Materials Webbed Type with Applying Discourse Analysis on Students Grade VIII in Physics Class

    Science.gov (United States)

    Sukariasih, Luh

    2017-05-01

    This study aims to produce teaching materials integrated natural science (IPA) webbed type of handout types are eligible for use in integrated science teaching. This type of research IS a kind of research and development / Research and Development (R & D) with reference to the 4D development model that is (define, design, develop, and disseminate). Data analysis techniques used to process data from the results of the assessment by the validator expert, and the results of the assessment by teachers and learners while testing is limited (12 students of class VIII SMPN 10 Kendari) using quantitative descriptive data analysis techniques disclosed in the distribution of scores on the scale of five categories grading scale that has been determined. The results of due diligence material gain votes validator material in the category of “very good” and “good”, of the data generated in the feasibility test presentation obtained the category of “good” and “excellent”, from the data generated in the feasibility of graphic test obtained the category of “very good “and” good “, as well as of the data generated in the test the feasibility of using words and language obtained the category of“very good “and” good “, so with qualifications gained the teaching materials IPA integrated type webbed by applying discourse analysis on the theme of energy and food for Junior High School (SMP) grade VIII suitable as teaching materials. In limited testing, data generated in response to a science teacher at SMPN 10 Kendari to product instructional materials as “excellent”, and from the data generated while testing is limited by the 12 students of class VIII SMPN 10 Kendari are more students who score indicates category “very good”, so that the qualification obtained by the natural science (IPA) teaching material integrated type webbed by applying discourse analysis on the theme of energy and food for SMP / class VIII fit for use as teaching material.

  2. Graded tensor calculus

    International Nuclear Information System (INIS)

    Scheunert, M.

    1982-10-01

    We develop a graded tensor calculus corresponding to arbitrary Abelian groups of degrees and arbitrary commutation factors. The standard basic constructions and definitions like tensor products, spaces of multilinear mappings, contractions, symmetrization, symmetric algebra, as well as the transpose, adjoint, and trace of a linear mapping, are generalized to the graded case and a multitude of canonical isomorphisms is presented. Moreover, the graded versions of the classical Lie algebras are introduced and some of their basic properties are described. (orig.)

  3. The Development of the easyCBM CCSS Reading Assessments: Grade 3. Technical Report #1221

    Science.gov (United States)

    Alonzo, Julie; Park, Bitnara Jasmine; Tindal, Gerald

    2012-01-01

    In this technical report, we document the development and piloting of easyCBM reading measures aligned to the Common Core State Standards, designed for use in screening students at risk for reading difficulty and monitoring their progress as they develop reading skills. The measures, which assess students' ability to respond to…

  4. Language Skills, Peer Rejection, and the Development of Externalizing Behavior from Kindergarten to Fourth Grade

    Science.gov (United States)

    Menting, Barbara; Van Lier, Pol A. C.; Koot, Hans M.

    2011-01-01

    Background: Children with poorer language skills are more likely to show externalizing behavior problems, as well as to become rejected by their peers. Peer rejection has also been found to affect the development of externalizing behavior. This study explored the role of peer rejection in the link between language skills and the development of…

  5. Ground Systems Development and Operations (GSDO) Education 101: Exploration Begins Here [Grades 9-12

    Science.gov (United States)

    Hill, Trudy

    2012-01-01

    Presentation to inform the non-NASA general public and school children of ground systems development and operations activities at Kennedy Space Center, particularly on what GSDO is and does, in a high level overview.

  6. Dosimetric properties of bio minerals applied to high-dose dosimetry using the TSEE technique

    International Nuclear Information System (INIS)

    Vila, G. B.; Caldas, L. V. E.

    2014-08-01

    The study of the dosimetric properties such as reproducibility, the residual signal, lower detection dose, dose-response curve and fading of the thermally stimulated emission exo electronic (TSEE) signal of Brazilian bio minerals has shown that these materials present a potential use as radiation dosimeters. The reproducibility within ± 10% for oyster shell, mother-of-pearl and coral reef samples showed that the signal dispersion is small when compared with the mean value of the measurements. The study showed that the residual signal can be eliminated with a thermal treatment at 300 grades C/1 h. The lower detection dose of 9.8 Gy determined for the oyster shell samples when exposed to beta radiation and 1.6 Gy for oyster shell and mother-of-pearl samples when exposed to gamma radiation can be considered good, taking into account the high doses of this study. The materials presented linearity at the dose response curves in some ranges, but the lack of linearity in other cases presents no problem since a good mathematical description is possible. The fading study showed that the loss of TSEE signal can be minimized if the samples are protected from interferences such as light, heat and humidity. Taking into account the useful linearity range as the main dosimetric characteristic, the tiger shell and oyster shell samples are the most suitable for high-dose dosimetry using the TSEE technique. (Author)

  7. Dosimetric properties of bio minerals applied to high-dose dosimetry using the TSEE technique

    Energy Technology Data Exchange (ETDEWEB)

    Vila, G. B.; Caldas, L. V. E., E-mail: gbvila@ipen.br [Instituto de Pesquisas Energeticas e Nucleares / CNEN, Av. Lineu Prestes 2242, Cidade Universitaria, 05508-000 Sao Paulo (Brazil)

    2014-08-15

    The study of the dosimetric properties such as reproducibility, the residual signal, lower detection dose, dose-response curve and fading of the thermally stimulated emission exo electronic (TSEE) signal of Brazilian bio minerals has shown that these materials present a potential use as radiation dosimeters. The reproducibility within ± 10% for oyster shell, mother-of-pearl and coral reef samples showed that the signal dispersion is small when compared with the mean value of the measurements. The study showed that the residual signal can be eliminated with a thermal treatment at 300 grades C/1 h. The lower detection dose of 9.8 Gy determined for the oyster shell samples when exposed to beta radiation and 1.6 Gy for oyster shell and mother-of-pearl samples when exposed to gamma radiation can be considered good, taking into account the high doses of this study. The materials presented linearity at the dose response curves in some ranges, but the lack of linearity in other cases presents no problem since a good mathematical description is possible. The fading study showed that the loss of TSEE signal can be minimized if the samples are protected from interferences such as light, heat and humidity. Taking into account the useful linearity range as the main dosimetric characteristic, the tiger shell and oyster shell samples are the most suitable for high-dose dosimetry using the TSEE technique. (Author)

  8. The Development of Learning Model Based on Problem Solving to Construct High-Order Thinking Skill on the Learning Mathematics of 11th Grade in SMA/MA

    Science.gov (United States)

    Syahputra, Edi; Surya, Edy

    2017-01-01

    This paper is a summary study of team Postgraduate on 11th grade. The objective of this study is to develop a learning model based on problem solving which can construct high-order thinking on the learning mathematics in SMA/MA. The subject of dissemination consists of Students of 11th grade in SMA/MA in 3 kabupaten/kota in North Sumatera, namely:…

  9. Citizenship development of adolescents during the lower grades of secondary education.

    Science.gov (United States)

    Geboers, Ellen; Geijsel, Femke; Admiraal, Wilfried; Jorgensen, Terrence; ten Dam, Geert

    2015-12-01

    The present study focuses on the development of citizenship competences of Dutch adolescents, including the political and social aspects as part of adolescents' daily lives. We followed 5070 adolescents aged 12-16 years across a three-year period in lower secondary education. The variance on school and student level was estimated and a three-level mixed-effects regression model was fit to analyze differences in citizenship development. The results indeed show development of citizenship competences during secondary school, but the observed patterns were not always positive. Students generally showed an increase in their citizenship knowledge, but a decline in their societal interest, prosocial ability and reflective thinking. Differences between groups of students could be explained by both schools and student characteristics. Especially girls and minority students developed the most citizenship competences. Understanding these differences is important for schools to improve their practices in ways that support the development of citizenship competences of various groups of students. Copyright © 2015 The Foundation for Professionals in Services for Adolescents. Published by Elsevier Ltd. All rights reserved.

  10. Understanding Teacher Perceptions in a Professional Development Program for a Middle Grade Science

    Science.gov (United States)

    Deloney, Dericka B.

    The standards-based framework requires teachers to evaluate and in some cases change their instructional approach to more student-centered and inquiry-based in an effort to help students meet the standards. The rationale for this study was to determine the skills needed for teachers to be effective in a standard-based, problem-based learning (PBL) constructivist classroom. Traditionally, teachers in this school district transitioning from teacher to student-centered classrooms need new skills when implementing this type of instruction. A qualitative case study design served to highlight the research questions for this project study. The participants in this study participated in data collection activities that include a multiple-choice survey, an interview, and the sharing of their PBL units. Artifacts, professional development teaching resources, from the workshop added credence to the survey and interview responses. The findings from each research question addressed the teachers' perception of their understanding and the obstacles of instructional design, development, and implementation the participants encountered. The results of this study indicated that teachers had problems with designing and implementing this instructional strategy due to lack of time and resources. This data assisted the development of district specific PBL sustainable professional development program that could be adaptable to other curriculums and school systems. Social change resulting from this study could include a framework for developing K-12 professional development as well as instructional programs that incorporates PBL curriculum design to enhance the student's inquiry, problem-solving, and decision-making skills that in turn should change their academic achievement and scores on high stakes test in science.

  11. Application of locally developed pavement temperature prediction algorithms in performance grade (PG) binder selection

    CSIR Research Space (South Africa)

    Denneman, E

    2007-07-01

    Full Text Available , in other words, data from outside the datasets against which the model was developed. The Viljoen algorithms form the basis of newly developed pavement temperature prediction software, called CSIR ThermalPADS. The use of this software in HMA... is provided as Equation 3. The ThermalPADS software contains a more accurate approximation of the daily solar declination. Declination=23.45º⋅cos[360º365⋅N 10] (3) where: N = day of the year (with 1st of January = 1) The equation for maximum asphalt...

  12. Dosimetric assessment of swallowing examinations with videofluoroscopy

    International Nuclear Information System (INIS)

    Costa, M.M.B.; Canevaro, L.V.; Azevedo, A.C.P.

    2001-01-01

    Dosimetric analysis measurements of the Dose-Area-Product (DAP) of 7 individuals were estimated for the deglutition dynamic using the videofluoroscopic method. The aim of this study is to establish in a preliminary way, typical DAP values for this kind of study. The DAP values were obtained attaching to the X ray tube exit, an ionization chamber from PTW and a Diamentor M4 meter. The typical DAP values obtained during the videofluoroscopic evaluation of the deglutition dynamic, including its three phases, was: 4101 ± 881 cGy.cm 2 and the typical DAP rate was 577 ± 94 cGy.cm 2 /min. These values refer to a standard patient (1.57 cm height, 56 kg. weight) and a protocol that can be performed in about 7 minutes. The values, defined herein as typical refer to the used protocol. To our knowledge, the mean DAP rate is a good parameter to estimate radiation exposure from videofluoroscopic study of swallowing process. (author)

  13. Gamma Putty dosimetric studies in electron beam

    Directory of Open Access Journals (Sweden)

    Aime M Gloi

    2016-01-01

    Full Text Available Traditionally, lead has been used for field shaping in megavoltage electron beams in radiation therapy. In this study, we analyze the dosimetric parameters of a nontoxic, high atomic number (Z = 83, bismuth-loaded material called Gamma Putty that is malleable and can be easily molded to any desired shape. First, we placed an ionization chamber at different depths in a solid water phantom under a Gamma Putty shield of thickness (t = 0, 3, 5, 10, 15, 20, and 25 mm, respectively and measured the ionizing radiation on the central axis (CAX for electron beam ranging in energies from 6 to 20 MeV. Next, we investigated the relationship between the relative ionization (RI measured at a fixed depth for several Gamma Putty shield at different cutout diameters ranging from 2 to 5 cm for various beam energies and derived an exponential fitting equation for clinical purposes. The dose profiles along the CAX show that bremsstrahlung dominates for Gamma Putty thickness >15 mm. For high-energy beams (12-20 MeV and all Gamma Putty thicknesses up to 25 mm, RI below 5% could not be achieved due to the strong bremsstrahlung component. However, Gamma Putty is a very suitable material for reducing the transmission factor below 5% and protecting underlying normal tissues for low-energy electron beams (6-9 MeV.

  14. Neutron sources and its dosimetric characteristics

    International Nuclear Information System (INIS)

    Vega C, H.R.; Manzanares A, E.; Hernandez D, V.M.; Mercado S, G.A.; Gallego D, E.; Lorente F, A.

    2005-01-01

    By means of Monte Carlo methods the spectra of the produced neutrons 252 Cf, 252 Cf/D 2 O, 241 Am Be, 239 Pu Be, 140 La Be, 239 Pu 18 O 2 and 226 Ra Be have been calculated. With the information of the spectrum it was calculated the average energy of the neutrons of each source. By means of the fluence coefficients to dose it was determined, for each one of the studied sources, the fluence factors to dose. The calculated doses were H, H * (10), H p,sIab (10, 0 0 ), E AP and E ISO . During the phase of the calculations the sources were modeled as punctual and their characteristics were determined to 100 cm in the hole. Also, for the case of the sources of 239 Pu Be and 241 Am Be, were carried out calculations modeling the sources with their respective characteristics and the dosimetric properties were determined in a space full with air. The results of this last phase of the calculations were compared with the experimental results obtained for both sources. (Author)

  15. A genetically engineered ovarian cancer mouse model based on fallopian tube transformation mimics human high-grade serous carcinoma development.

    Science.gov (United States)

    Sherman-Baust, Cheryl A; Kuhn, Elisabetta; Valle, Blanca L; Shih, Ie-Ming; Kurman, Robert J; Wang, Tian-Li; Amano, Tomokazu; Ko, Minoru S H; Miyoshi, Ichiro; Araki, Yoshihiko; Lehrmann, Elin; Zhang, Yongqing; Becker, Kevin G; Morin, Patrice J

    2014-07-01

    Recent evidence suggests that ovarian high-grade serous carcinoma (HGSC) originates from the epithelium of the fallopian tube. However, most mouse models are based on the previous prevailing view that ovarian cancer develops from the transformation of the ovarian surface epithelium. Here, we report the extensive histological and molecular characterization of the mogp-TAg transgenic mouse, which expresses the SV40 large T-antigen (TAg) under the control of the mouse müllerian-specific Ovgp-1 promoter. Histological analysis of the fallopian tubes of mogp-TAg mice identified a variety of neoplastic lesions analogous to those described as precursors to ovarian HGSC. We identified areas of normal-appearing p53-positive epithelium that are similar to 'p53 signatures' in the human fallopian tube. More advanced proliferative lesions with nuclear atypia and epithelial stratification were also identified that were morphologically and immunohistochemically reminiscent of human serous tubal intraepithelial carcinoma (STIC), a potential precursor of ovarian HGSC. Beside these non-invasive precursor lesions, we also identified invasive adenocarcinoma in the ovaries of 56% of the mice. Microarray analysis revealed several genes differentially expressed between the fallopian tube of mogp-TAg and wild-type (WT) C57BL/6. One of these genes, Top2a, which encodes topoisomerase IIα, was shown by immunohistochemistry to be concurrently expressed with elevated p53 and was specifically elevated in mouse STICs but not in the surrounding tissues. TOP2A protein was also found elevated in human STICs, low-grade and high-grade serous carcinoma. The mouse model reported here displays a progression from normal tubal epithelium to invasive HGSC in the ovary, and therefore closely simulates the current emerging model of human ovarian HGSC pathogenesis. This mouse therefore has the potential to be a very useful new model for elucidating the mechanisms of serous ovarian tumourigenesis, as well as

  16. The research of 4th grade mathematical curriculum electronic picture book construction and development in integrating indigenous culture

    Science.gov (United States)

    Chen, Yen Ting; Hsin Wang, Juei

    2017-02-01

    This research aimed at integrating Seediq culture and mathematical course design for fourth-grade elementary school, and then transforming this mathematical course into an electronic picture book. During the process of electronic book development, the researchers collected videos of six participants engaged in discussion, reflection minutes after the meeting written by the attendants, the researchers' observation and review journals, and conversations with the participants. Then, researchers utilized Content Analysis to explore, try, review and retry steps of electronic book making process. The main findings: There are four periods of electronic book making process, research occurrence period, curriculum design period, electronic book transformation period, and result evaluation period. The picture book included the White Stone Legend born from Seediq seniors, historical battle for hunting field between tribes, and concepts of approximation, angle, triangle, and quadrangle features. At last, with the research result, this article presents the corroboration of related works, and then proposes suggestions of electronic book teaching and follow-up studies.

  17. Dosimetric systems of high dose, dose rate and dose uniformity in food and medical products; Sistemas dosimetricos de altas dosis, tasa de dosis y uniformidad de dosis en alimentos y producto medico

    Energy Technology Data Exchange (ETDEWEB)

    Vargas, J.; Vivanco, M.; Castro, E., E-mail: jvargas@ipen.gob.pe [Instituto Peruano de Energia Nuclear, Av. Canada 1470, San Borja, Lima (Peru)

    2014-08-15

    In the Instituto Peruano de Energia Nuclear (IPEN) we use the chemical dosimetry Astm-E-1026 Fricke as a standard dosimetric system of reference and different routine dosimetric systems of high doses, according to the applied doses to obtain the desired effects in the treated products and the doses range determined for each type of dosimeter. Fricke dosimetry is a chemical dosimeter in aqueous solution indicating the absorbed dose by means an increase in absorbance at a specific wavelength. A calibrated spectrophotometer with controlled temperature is used to measure absorbance. The adsorbed dose range should cover from 20 to 400 Gy, the Fricke solution is extremely sensitive to organic impurities, to traces of metal ions, in preparing chemical products of reactive grade must be used and the water purity is very important. Using the referential standard dosimetric system Fricke, was determined to March 5, 2013, using the referential standard dosimetric system Astm-1026 Fricke, were irradiated in triplicate Fricke dosimeters, to 5 irradiation times (20; 30; 40; 50 and 60 seconds) and by linear regression, the dose rate of 5.400648 kGy /h was determined in the central point of the irradiation chamber (irradiator Gamma cell 220 Excel), applying the decay formula, was compared with the obtained results by manufacturers by means the same dosimetric system in the year of its manufacture, being this to the date 5.44691 kGy /h, with an error rate of 0.85. After considering that the dosimetric solution responds to the results, we proceeded to the irradiation of a sample of 200 g of cereal instant food, 2 dosimeters were placed at the lateral ends of the central position to maximum dose and 2 dosimeters in upper and lower ends as minimum dose, they were applied same irradiation times; for statistical analysis, the maximum dose rate was 6.1006 kGy /h and the minimum dose rate of 5.2185 kGy /h; with a dose uniformity of 1.16. In medical material of micro pulverized bone for

  18. The Arts, the Common Core, and English Language Development in the Primary Grades

    Science.gov (United States)

    Greenfader, Christa Mulker; Brouillette, Liane

    2017-01-01

    Background/Context: Throughout schooling, English learners (ELs) perform well below their monolingual English-speaking peers on literacy assessments, and Hispanics make up the majority of EL students in the United States. There is a strong consensus about the importance of early English oral language skills for ELs' literacy development, yet…

  19. Number Sense: Strategies for Helping Preschool through Grade 3 Children Develop Math Skills

    Science.gov (United States)

    Witzel, Bradley S.; Ferguson, Christine J.; Mink, Deborah V.

    2012-01-01

    Number sense development in young children has been linked to future math achievement in a manner similar to the way phonological awareness (i.e., children's awareness and use of sounds within a language to make meaning) has been linked to reading achievement (e.g., Kosanovich, Weinstein, & Goldman 2009). That is, they may be indicators of future…

  20. Developing Essential Understanding of Functions for Teaching Mathematics in Grades 9-12

    Science.gov (United States)

    Lloyd, Gwendolyn; Beckmann, Sybilla; Zbiek, Rose Mary; Cooney, Thomas

    2010-01-01

    Are sequences functions? What can't the popular "vertical line test" be applied in some cases to determine if a relation is a function? How does the idea of rate of change connect with simpler ideas about proportionality as well as more advanced topics in calculus? Helping high school students develop a robust understanding of functions requires…

  1. Challenges and Gaps in Children's Transition from Early Childhood Development to Grade One in Zimbabwe

    Science.gov (United States)

    Chikwiri, E.; Musiyiwa, J.

    2017-01-01

    The study focused on challenges and gaps faced by children during the transition period from early childhood development (ECD) to primary education and possible solutions to them. It adopted the qualitative methodological approach through the use of Focus Group Discussions with councillors, education officials, child care workers, chiefs, parents…

  2. Development of nuclear grade type 316 stainless steel for BWR pipings

    International Nuclear Information System (INIS)

    Kowaka, Masamichi; Nagano, Hiroo; Yoshikawa, Kunihiko; Miura, Minoru; Ota, Kunio.

    1981-01-01

    The countermeasures were established against the grain boundary stress corrosion cracking in the heat-affected zone of 304 stainless steel pipings used for recirculating system and others of BWRs. Sumitomo Metal Industries, Ltd. has engaged in the development of the stainless steel having excellent resistance to stress corrosion cracking, substituting for 304 stainless steel. In order to prevent stainless steel from becoming sensitive to the grain boundary stress corrosion cracking, the reduction of carbon content, or the addition of the elements stabilizing carbon in steel are conceivable. 316 L stainless steel was selected as the base for development, because it is a low carbon steel (C <= 0.03%) and contains Mo effective for improving the pitting corrosion resistance and restricting the steel to become sensitive. The requirements for the piping materials for BWRs are the resistance to stress corrosion cracking in high temperature, high pressure water, excellent strength and weldability, and the possibility of the commercial production of pipes. For the purpose of developing 316 stainless steel pipes, the effects of Mo and trace elements on the stress corrosion cracking resistance, the effects of C, N and grain size on the strength, and the effect of N on the weldability were examined, and the composition design of 316 stainless steel for atomic energy use was carried out. The result is given. (Kako, I.)

  3. Using writing as a vehicle to promote and develop scientific concepts and process skills in fourth-grade students

    Science.gov (United States)

    Disimoni, Katherine Cecilia

    The development of conceptual knowledge, particularly at the elementary level, is one area in which researchers and educators have noted remarkable deficiencies. The purpose of this descriptive study was to observe the impact of the use of writing as a thinking tool on the promotion and development of scientific concepts and science process skills in elementary students in the discipline of science. Reports from some of the publications for science research and educational progress cited the direct links of writing effectiveness to the development of skills in critical thinking. The study consisted of 12 fourth-grade students in the control group and their 12 fourth-grade counterparts in the experimental group. The treatment for the study was the use of learning logs by the experimental group to record their written responses to predesigned prompts related to hands-on science experiences during the intervention period. Their counterparts did no writing. Statistical measures used were Student's t tests to determine if significance was present. A pretest and posttest were given that involved written responses to the same prompt. Three judges used a specially designed rubric to evaluate and score the writing. Significant differences were found when the scores of the experimental group were analyzed between pretest and posttest. Also, a standardized test to assess basic process skills was administered prior to and after the intervention. There were no statistical differences found in either group to demonstrate that writing effected the development of process skills. The researcher determined that perhaps writing is not the best way to promote process skills. Rather, engaging in science is the best way. These skills are built separately but used in tandem, particularly when learning about science and mathematics. The implications of this study impact upon several areas of education which make up paradigms leading to good practice based on sound theory. These components

  4. Using measurable dosimetric quantities to characterize the inter-structural tradeoff in inverse planning

    Science.gov (United States)

    Liu, Hongcheng; Dong, Peng; Xing, Lei

    2017-08-01

    Traditional inverse planning relies on the use of weighting factors to balance the conflicting requirements of different structures. Manual trial-and-error determination of weighting factors has long been recognized as a time-consuming part of treatment planning. The purpose of this work is to develop an inverse planning framework that parameterizes the dosimetric tradeoff among the structures with physically meaningful quantities to simplify the search for clinically sensible plans. In this formalism, instead of using weighting factors, the permissible variation range of the prescription dose or dose volume histogram (DVH) of the involved structures are used to characterize the ‘importance’ of the structures. The inverse planning is then formulated into a convex feasibility problem, called the dosimetric variation-controlled model (DVCM), whose goal is to generate plans with dosimetric or DVH variations of the structures consistent with the pre-specified values. For simplicity, the dosimetric variation range for a structure is extracted from a library of previous cases which possess similar anatomy and prescription. A two-phase procedure (TPP) is designed to solve the model. The first phase identifies a physically feasible plan to satisfy the prescribed dosimetric variation, and the second phase automatically improves the plan in case there is room for further improvement. The proposed technique is applied to plan two prostate cases and two head-and-neck cases and the results are compared with those obtained using a conventional CVaR approach and with a moment-based optimization scheme. Our results show that the strategy is able to generate clinically sensible plans with little trial and error. In all cases, the TPP generates a very competitive plan as compared to those obtained using the alternative approaches. Particularly, in the planning of one of the head-and-neck cases, the TPP leads to a non-trivial improvement in the resultant dose distribution

  5. [Development and Effects of a Children's Sex Education Program for the Parents of Lower Elementary Grade Students].

    Science.gov (United States)

    Lee, Eun Mi; Kim, Hyunlye

    2017-04-01

    This study was done to develop a children's sex education program for the parents of lower elementary grade students and to evaluate its effects on sexual knowledge, gender role attitude, parent efficacy for child's sex education, and marital consistency. A quasi-experimental with a non-equivalent control group pretest-posttest design was used. The participants were 29 couples (58 parents, experimental group=28, control group=30) from G city. The 5-week (5-session) program was developed based on 'A theory of protection: parents as sex educators' and used the case-based small group learning method. Data were collected during July and August 2015. The characteristics of the program developed in the present study were a theoretical-based, client-centered, multi-method. After the intervention, the experimental group showed a significant improvement in sexual knowledge, gender role attitudes, parent efficacy for child's sex education, and marital consistency, compared to the control group. The effect sizes of the program were .64 (knowledge), .65 (gender role attitudes), and .68 (parent efficacy). The results of this study provided implications for the parents as effective sex educator and the role expansion of school health nurses. © 2017 Korean Society of Nursing Science

  6. Development of oral food-grade delivery systems: current knowledge and future challenges.

    Science.gov (United States)

    Benshitrit, Revital Cohen; Levi, Carmit Shani; Tal, Sharon Levi; Shimoni, Eyal; Lesmes, Uri

    2012-01-01

    In recent years there has been an increasing interest in the development of new and efficient oral food delivery systems as tools to prevent disease and promote human health and well-being. Such vehicles are sought to protect bioactive ingredients added to food while controlling and targeting their release as they pass through the human gastrointestinal tract (GIT). This review aims to summarize the key concepts of food delivery systems, their characterization and evaluation. Particularly, evaluation of their performance within the human GIT is discussed. To this end an overview of several in vivo and in vitro methods currently applied for the study of such systems is given. Although considered to be still in its infancy, this promising field of research is likely to infiltrate into real products through rational design. In order for such efforts to materialize into real products some challenges still need to be met and are discussed herein. Overall, it seems that adopting a comprehensive pharmacological approach and relevant cutting edge tools are likely to facilitate innovations and help elucidate and perhaps tailor delivery systems' behavior in the human GIT.

  7. Design and dosimetric considerations of a modified COMS plaque: The reusable 'seed-guide' insert

    International Nuclear Information System (INIS)

    Astrahan, Melvin A.; Szechter, Andrzej; Finger, Paul T.

    2005-01-01

    The Collaborative Ocular Melanoma Study (COMS) developed a standardized set of eye plaques that consist of a 0.5 mm thick bowl-like gold alloy backing with a cylindrical collimating lip. A Silastic seed carrier into which 125 I seeds are loaded was designed to fit within the backing. The carrier provides a standardized seed pattern and functions to offset the seeds by 1.0 mm from the concave (front) surface of the carrier. These Silastic carriers have been found to be difficult to load, preclude flash sterilization, and are a source of dosimetric uncertainty because the effective atomic number of Silastic is significantly higher than that of water. The main dosimetric effect of the Silastic carrier is a dose-reduction (compared to homogeneous water) of approximately 10%-15% for 125 I radiation. The dose reduction is expected to be even greater for 103 Pd radiation. In an attempt to improve upon, yet retain as much of the familiar COMS design as possible, we have developed a thin 'seed-guide' insert made of gold alloy. This new insert has cutouts which match the seed pattern of the Silastic carrier, but allows the seeds to be glued directly to the inner surface of the gold backing using either dental acrylic or a cyanoacrylate adhesive. When glued directly to the gold backing the seeds are offset a few tenths of a millimeter further away from the scleral surface compared to using the Silastic carrier. From a dosimetric perspective, the space formerly occupied by the Silastic carrier is now assumed to be water equivalent. Water equivalency is a desirable attribute for this space because it eliminates the dosimetric uncertainties related to the atomic composition of Silastic and thereby facilitates the use of either 125 I and/or 103 Pd seeds. The caveat is that a new source of dosimetric uncertainty would be introduced were an air bubble to become trapped in this space during or after the surgical insertion. The presence of air in this space is modeled and the

  8. The Effects of Using Drawings in Developing Young Children's Mathematical Word Problem Solving: A Design Experiment with Third-Grade Hungarian Students

    Science.gov (United States)

    Csikos, Csaba; Szitanyi, Judit; Kelemen, Rita

    2012-01-01

    The present study aims to investigate the effects of a design experiment developed for third-grade students in the field of mathematics word problems. The main focus of the program was developing students' knowledge about word problem solving strategies with an emphasis on the role of visual representations in mathematical modeling. The experiment…

  9. The Development of K-8 Progress Monitoring Measures in Mathematics for Use with the 2% and General Education Populations: Grade 1. Technical Report # 0919

    Science.gov (United States)

    Alonzo, Julie; Tindal, Gerald

    2009-01-01

    In this technical report, we describe the development and piloting of a series of mathematics progress monitoring measures intended for use with students in grade 1. These measures, available as part of easyCBM [TM], an online progress monitoring assessment system, were developed in 2008 and administered to approximately 2800 students from schools…

  10. Development of Society in the United States. American Civilization, Resource Unit II, Grade 10. Providence Social Studies Curriculum Project.

    Science.gov (United States)

    Providence Public Schools, RI.

    GRADES OR AGES: Grades 10 and 11. SUBJECT MATTER: Social studies; United States civilization. ORGANIZATION AND PHYSICAL APPEARANCE: The major portion of the guide is divided into six subunits, each of which is laid out in three columns, one each for topics, activities, and materials. Other sections are in list form. The guide is mimeographed and…

  11. Developing Responsibility for Completing and Handing in Daily Homework Assignments for Students in Grades Three, Four, and Five.

    Science.gov (United States)

    Shepard, Joan M.

    This practicum was designed to increase responsibility for completing and handing in homework among students in grades three, four, and five in a mid-Atlantic school district. Of a total of 128 students in these grades, 28 were identified to learn strategies to aid in completing homework. Nine solution strategies were employed: (1) provide…

  12. Dosimetric methods for and influence of exposure parameters on the establishment of reference doses in mammography

    NARCIS (Netherlands)

    Zoetelief, J.; Fitzgerald, M.; Leitz, W.; Säbel, M.

    1998-01-01

    For the establishment of reference doses in mammography it is important to apply a dosimetric model relevant for risk assessment. Differences in dosimetric methods applied in mammography are related to the dosemeters used, e.g. thermoluminescent detectors and ionisation chambers, and the dosimetric

  13. Arrested development - a comparative analysis of multilayer corona textures in high-grade metamorphic rocks

    Science.gov (United States)

    Ogilvie, Paula; Gibson, Roger L.

    2017-02-01

    -limiting reaction mechanisms and their petrogenetic signatures in increasingly complex, higher-variance systems has facilitated the refinement of chemical fractionation and partial equilibration diffusion models necessary to more fully understand corona development. Through the application of quantitative physical diffusion models of coronas coupled with phase equilibria modelling utilizing calculated chemical potential gradients, it is possible to model the evolution of a corona through P-T-X-t space by continuous, steady-state and/or sequential, episodic reaction mechanisms. Most coronas in granulites form through a combination of these endmember reaction mechanisms, each characterized by distinct textural and chemical potential signatures with very different petrogenetic implications. An understanding of the inherent petrogenetic limitations of a reaction mechanism model is critical if an appropriate interpretation of P-T evolution is to be inferred from a corona. Since corona modelling employing calculated chemical potential gradients assumes nothing about the sequence in which the layers form and is directly constrained by phase compositional variation within a layer, it allows far more nuanced and robust understanding of corona evolution and its implications for the path of a rock in P-T-X space.

  14. A Developing Curriculum in English: Kindergarten Through Grade Twelve. Second Edition. Studies in Curriculum Development No. 3.

    Science.gov (United States)

    Gibbs, Vanita; Mullican, James

    This monograph describes a curriculum first published 14 years ago that is based on students' human development. The described curriculum utilizes a framework of the language arts of listening, speaking, reading, writing, and literature understanding and leaves to the imagination and skill of the individual teacher how the curriculum is…

  15. The impact of virtual trips on the development of Arabic language listening skills among third grade students in Jordan

    Directory of Open Access Journals (Sweden)

    Nail M. Alhajya

    2018-03-01

    Full Text Available This study aimed at investigating the impact of virtual trips on developing Arabic language listening skills among third grade students in Jordan. The researchers used a quasi-experimental design to answer the research questions. The study sample consisted of 48 students who were chosen purposely. Those participants were divided randomly into two groups: 1 experimental group which consisted of 24 students who were taught by using a Virtual Trip Model (VTM, and 2 control group which consisted of 24 students who were taught by using a traditional method of teaching. To achieve the study objectives, the researchers developed a content-based VTM and achievement test to measure Arabic language listening skills. Reliability and validity of the study instruments were checked. To answer the study questions, means and standard deviations were calculated, and ANCOVA test was used. Study results revealed that there were statistically significant differences (α=0.05 between means of students’ achievement test scores attributed to teaching method variable, and in favor of the experimental group.  Furthermore, there were no statistically significant differences (α=0.05 between means of students’ achievements test scores attributed to gender variable, and the interaction between teaching method and gender variables. Additional implications and future recommendations were argued.

  16. FBX aqueous chemical dosimeter for measurement of dosimetric parameters.

    Science.gov (United States)

    Moussous, O; Medjadj, T; Benguerba, M

    2011-02-01

    We investigated the ferrous sulphate-benzoic acid-xylenol orange (FBX) aqueous chemical dosimeter for measurement of dosimetric parameters such as the output factor, backscatter factor and lateral beam profiles for different square fields sizes for (60)Co γ-rays. A water phantom was employed to measure these parameters. An ionization chamber (IC) was used for calibration and comparison. A comparison of the resulting measurements with an ionization chamber's measured parameters showed good agreement. We thus believe that the tissue equivalent FBX dosimetry system can measure the dosimetric parameters for (60)Co with reasonable accuracy. Copyright © 2010 Elsevier Ltd. All rights reserved.

  17. Dosimetric predictors of hypothyroidism in oropharyngeal cancer patients treated with intensity-modulated radiation therapy

    International Nuclear Information System (INIS)

    Chyan, Arthur; Chen, Josephine; Shugard, Erin; Lambert, Louise; Quivey, Jeanne M; Yom, Sue S

    2014-01-01

    Radiation to the neck has long been associated with an elevated risk of hypothyroidism development. The goal of the present work is to define dosimetric predictors of hypothyroidism in oropharyngeal cancer (OPC) patients treated with intensity-modulated radiation therapy. Data for 123 patients, with a median follow up of 4.6 years, were retrospectively analyzed. Patients with elevated thyroid-stimulating hormone levels or with a clinical diagnosis were categorized as hypothyroid. Patient demographic parameters, thyroid volume, mean thyroid dose, the percent of thyroid volume receiving minimum specified dose levels (VxxGy), and the absolute thyroid volume spared from specified dose levels (VSxxGy) were analyzed. Normal-tissue complication probability (NTCP) was also calculated using several recently published models. Thyroid volume and many radiation dosimetric parameters were statistically different in the hypothyroid group. For the patients with initial thyroid volumes of 8 cc or greater, several dosimetric parameters were found to define subgroups at statistically significant lower risk of developing hypothyroidism. Patients with VS45 Gy of at least 3 cc, VS50 Gy at least 5 cc, VS50 Gy at least 6 cc, V50 Gy below 45%, V50 Gy below 55%, or mean thyroid dose below 49 Gy had a 28-38% estimated risk of hypothyroidism at 3 years compared to a 55% risk for the entire study group. Patients with a NTCP of less than 0.75 or 0.8, calculated using recently published models, were also observed to have a lower risk of developing hypothyroidism. Based on long-term follow up data for OPC patients treated with IMRT, we recommend plan optimization objectives to reduce the volume of thyroid receiving over 45 Gy to significantly decrease the risk of developing hypothyroidism. The online version of this article (doi:10.1186/s13014-014-0269-4) contains supplementary material, which is available to authorized users

  18. Investigation of dosimetric characteristics of the high sensitivity LiF:Mg,Cu,P Thermoluminescent Dosemeter and its applications in diagnostic radiology - a review

    Energy Technology Data Exchange (ETDEWEB)

    Fung, K.L. E-mail: orkarl@polyu.edu.hk

    2004-05-01

    This study investigated the dosimetric properties of the high sensitivity TLD (Thermoluminescent Dosemeter) of LiF:Mg,Cu,P and its applications in diagnostic radiology. A reproducible readout and annealing regime for this high sensitivity TLD was developed in the initial part of this study with the newly installed automatic TLD Reader system. Basic dosimetric characteristics of this T.L. dosemeter were then investigated. This paved the foundation for subsequent selected novel application studies in diagnostic radiology. This study exploits the favourable dosimetric properties of these T.L. dosemeters in some selected novel dosimetric applications in diagnostic radiology with an anthropomorphic phantom. The applications studied in radiological procedures included: dose reduction in lumbar spine radiography utilizing the 'anode heel effect'; gonad dose variation with kV{sub p} in chest radiography; foetal dose comparison between computed tomography (CT) and computed radiography (CR) in X-ray pelvimetry; lens dose reduction with bismuth eye-shields in CT brain studies; foetal dose assessment of early pregnancy in common high risk radiological examinations. It is anticipated that the unique and favourable dosimetric performance of LiF:Mg,Cu,P T.L. phosphor will be exploited further in measurements of low level dose received by patients and staff in diagnostic radiological procedures such as paediatric X-ray examinations.

  19. Tumor Grade

    Science.gov (United States)

    ... Peer Review and Funding Outcomes Step 4: Award Negotiation & Issuance Manage Your Award Grants Management Contacts Monitoring ... may require immediate or more aggressive treatment. The importance of tumor grade in planning treatment and determining ...

  20. Ethnomathematical research and drama in education techniques: developing a dialogue in a geometry class of 10th grade students

    Directory of Open Access Journals (Sweden)

    Charoula Stathopoulou

    2015-07-01

    Full Text Available Ethnomathematical research, together with digital technologies (WebQuest and Drama-in-Education (DiE techniques, can create a fruitful learning environment in a mathematics classroom—a hybrid/third space—enabling increased student participation and higher levels of cognitive engagement. This article examines how ethnomathematical ideas processed within the experiential environment established by the Drama-in-Education techniques challenged students‘ conceptions of the nature of mathematics, the ways in which students engaged with mathematics learning using mind and body, and the ‗dialogue‘ that was developed between the Discourse situated in a particular practice and the classroom Discourse of mathematics teaching. The analysis focuses on an interdisciplinary project based on an ethnomathematical study of a designing tradition carried out by the researchers themselves, involving a search for informal mathematics and the connections with context and culture; 10th grade students in a public school in Athens were introduced to the mathematics content via an original WebQuest based on this previous ethnomathematical study; Geometry content was further introduced and mediated using the Drama-in-Education (DiE techniques. Students contributed in an unfolding dialogue between formal and informal knowledge, renegotiating both mathematical concepts and their perception of mathematics as a discipline.

  1. Ethnomathematical research and drama in education techniques: developing a dialogue in a geometry class of 10th grade students

    Directory of Open Access Journals (Sweden)

    Charoula Stathopoulou

    2015-01-01

    Full Text Available Ethnomathematical research, together with digital technologies (WebQuest and Drama-in-Education (DiE techniques, can create a fruitful learning environment in a mathematics classroom—a hybrid/third space—enabling increased student participation and higher levels of cognitive engagement. This article examines how ethnomathematical ideas processed within the experiential environment established by the Drama-in-Education techniques challenged students‘ conceptions of the nature of mathematics, the ways in which students engaged with mathematics learning using mind and body, and the ‗dialogue‘ that was developed between the Discourse situated in a particular practice and the classroom Discourse of mathematics teaching. The analysis focuses on an interdisciplinary project based on an ethnomathematical study of a designing tradition carried out by the researchers themselves, involving a search for informal mathematics and the connections with context and culture; 10th grade students in a public school in Athens were introduced to the mathematics content via an original WebQuest based on this previous ethnomathematical study; Geometry content was further introduced and mediated using the Drama-in-Education (DiE techniques. Students contributed in an unfolding dialogue between formal and informal knowledge, renegotiating both mathematical concepts and their perception of mathematics as a discipline.

  2. Developing Seventh Grade Students' Understanding of Complex Environmental Problems with Systems Tools and Representations: a Quasi-experimental Study

    Science.gov (United States)

    Doganca Kucuk, Zerrin; Saysel, Ali Kerem

    2017-03-01

    A systems-based classroom intervention on environmental education was designed for seventh grade students; the results were evaluated to see its impact on the development of systems thinking skills and standard science achievement and whether the systems approach is a more effective way to teach environmental issues that are dynamic and complex. A quasi-experimental methodology was used to compare performances of the participants in various dimensions, including systems thinking skills, competence in dynamic environmental problem solving and success in science achievement tests. The same pre-, post- and delayed tests were used with both the comparison and experimental groups in the same public middle school in Istanbul. Classroom activities designed for the comparison group (N = 20) followed the directives of the Science and Technology Curriculum, while the experimental group (N = 22) covered the same subject matter through activities benefiting from systems tools and representations such as behaviour over time graphs, causal loop diagrams, stock-flow structures and hands-on dynamic modelling. After a one-month systems-based instruction, the experimental group demonstrated significantly better systems thinking and dynamic environmental problem solving skills. Achievement in dynamic problem solving was found to be relatively stable over time. However, standard science achievement did not improve at all. This paper focuses on the quantitative analysis of the results, the weaknesses of the curriculum and educational implications.

  3. DEVELOPMENT OF AN EMAT IN-LINE INSPECTION SYSTEM FOR DETECTION, DISCRIMINATION, AND GRADING OF STRESS CORROSION CRACKING IN PIPELINES

    Energy Technology Data Exchange (ETDEWEB)

    Jeff Aron; Jon Gore, Roger Dalton; Stuart Eaton; Adrian Bowles; Owen Thomas; Tim Jarman

    2003-07-01

    This report describes progress, experiments, and results for a project to develop a pipeline inline inspection tool that uses electromagnetic acoustic transducers (EMATs) to detect and grade stress corrosion cracking (SCC). There is a brief introduction that gives background material about EMATs and relevant previous Tuboscope work toward a tool. This work left various choices about the modes and transducers for this project. The experimental section then describes the lab systems, improvements to these systems, and setups and techniques to narrow the choices. Improvements, which involved transducer matching networks, better magnetic biasing, and lower noise electronics, led to improved signal to noise (SNR) levels. The setups permitted transducer characterizations and interaction measurements in plates with man-made cracks, pipeline sections with SCC, and a full pipe with SCC. The latter were done with a moveable and compact EMAT setup, called a lab mouse, which is detailed. Next, the results section justifies the mode and transducer choices. These were for magnetostrictive EMATs and the use of EMAT launched modes: SH0 (at 2.1 MHz-mm) and SV1 (at 3.9 MHz-mm). This section then gives details of measurements on these modes. The measurements consisted of signal to noise ratio, insertion loss, magnetic biasing sensitivities crack reflection and transmission coefficients, beam width, standoff and tilt sensitivities. For most of the measurements the section presents analysis curves, such as reflection coefficient versus crack depth. Some notable results for the chosen modes are: that acceptable SNRs were generated in a pipe with magnetostrictive EMATs, that optimum bias for magnetostrictive transmitters and receivers is magnetic saturation, that crack reflection and transmission coefficients from crack interactions agree with 2 D simulations and seem workable for crack grading, and that the mouse has good waveform quality and so is ready for exhaustive measurement EMAT

  4. The Development Of Scientific Approach-oriented Science Learning Materials On Biotechnology And Food Production Topics For Grade IX Junior High School

    OpenAIRE

    Febrina, Ririn Febrina Ririn; Natalina, Mariani Natalina Mariani; Suryawati, Evi Suryawati Evi

    2015-01-01

    The aim of this research was to develop scientific approach-oriented science learning materials on biotechnology and food production topic for grade IX junior high school. The developments consisted of syllabus, lesson plans, worksheets, authentic assessment (paper and pencil test, attitude assessment, performance assessment, product assessment, project assessment, self-assessment and portofolio assessment). The development was conducted at Biology Education University of Riau and the pilot t...

  5. Radiation-induced liver disease after radiotherapy for hepatocellular carcinoma: clinical manifestation and dosimetric description

    International Nuclear Information System (INIS)

    Cheng, Jason Chia-Hsien; Wu, Jian-Kuen; Huang, Chao-Ming; Huang, David Y.; Cheng, Skye H.; Lin, Yu-Mong; Jian, James J.; Yang, Po-Sheng; Chuang, Vincent P.; Huang, Andrew T.

    2002-01-01

    Twelve patients with hepatocellular carcinoma and chronic hepatitis developed radiation-induced liver disease (RILD) after three-dimensional conformal radiotherapy. Six patients died of RILD and six recovered. Mean prescribed dose was 50.6±4.3 Gy, in a daily fraction of 1.8-2.0 Gy. Commonly used dosimetric parameters, such as fraction volume of normal liver with radiation dose >30 Gy, prediction score, and normal tissue complication probability, failed to differentiate the fatality and clinical types of this complication. Elevated transaminases are more frequently seen than ascites and elevated alkaline phosphamide are seen in patients with RILD

  6. Web 2.0 Tools and Academic Literacy Development in a US Urban School: A Case Study of a Second-Grade English Language Learner

    Science.gov (United States)

    Shin, Dong-shin

    2014-01-01

    This study explores a second-grade English language learner's literacy development and ability to use blogging for social and academic purposes, in the context of learning academic writing genres in a US urban school. Grounded in sociocultural theories, it conceptualizes learning as appropriation, and language as a dynamic and functional system of…

  7. The role of smoking and alcohol intake in the development of high-grade squamous intraepithelial lesions among high-risk HPV-positive women

    DEFF Research Database (Denmark)

    Tolstrup, Janne; Munk, Christian; Thomsen, Birthe Lykke

    2006-01-01

    -risk human papillomavirus positive women with normal cytology, comparing 94 women who developed high-grade squamous intraepithelial lesions with 454 women who remained cytologically normal. Logistic regression was applied for statistical analysis. RESULTS: Compared with never smokers, the odds ratio for high...

  8. Evaluation of Seeds of Science/Roots of Reading: Effective Tools for Developing Literacy through Science in the Early Grades-Light Energy Unit. CRESST Report 781

    Science.gov (United States)

    Goldschmidt, Pete; Jung, Hyekyung

    2011-01-01

    This evaluation focuses on the Seeds of Science/Roots of Reading: Effective Tools for Developing Literacy through Science in the Early Grades ("Seeds/Roots") model of science-literacy integration. The evaluation is based on a cluster randomized design of 100 teachers, half of which were in the treatment group. Multi-level models are employed to…

  9. The Impact of Educational Games-Based iPad Applications on the Development of Social Studies Achievement and Learning Retention among Sixth Grade Students in Jeddah

    Science.gov (United States)

    Najmuldeen, Hanan A.

    2017-01-01

    The present study aims to evaluate the impact of educational games-based iPad applications on the development of social studies achievement and learning retention. Sample consisted of (48) sixth grade primary students in Jeddah. The author adopted Quasi-experimental design of the experimental and control groups. She also provided the teacher a…

  10. Developing and Evaluating an Eighth Grade Curriculum Unit That Links Foundational Chemistry to Biological Growth: Paper 5--Using Teacher Measures to Evaluate the Promise of the Intervention

    Science.gov (United States)

    Flanagan, Jean C.; Herrmann-Abell, Cari F.; Roseman, Jo Ellen

    2013-01-01

    AAAS (American Association for the Advancement of Science) is collaborating with BSCS (Biological Sciences Curriculum Study) in the development of a curriculum unit for eighth grade students that connects fundamental chemistry and biology concepts to better prepare them for high school biology. Recognizing that teachers play an influential role in…

  11. Physical Education Teachers' Attitudes towards Teaching Character Education and Their Attitudes towards the Character Development of Their Fourth and/or Fifth Grade Students

    Science.gov (United States)

    Denaro, Edward Joseph

    2010-01-01

    The purpose of this study was to examine the attitudes of elementary school physical education teachers towards teaching character education related to the variables respect, honesty, fairness and self-discipline and to examine their attitudes towards the character development of their fourth and/or fifth grade students related to the variables…

  12. Dose reader of dosimetric foil; Czytnik dawki folii dozymetrycznej

    Energy Technology Data Exchange (ETDEWEB)

    Machaj, B.; Strzalkowski, J.; Smolko, K.

    1997-12-31

    Read out the absorbance of a dosimetric foil is accomplished by two beam spectrophotometer. Such a solution makes possible the compensation of light source instabilities and ensures higher stability of the dose reader. The error of absorbance measurement caused by the instabilities does not exceed 0.0004 A. (author). 3 refs, 3 figs.

  13. Development of communicative competences of the 8th and 9th grade students in the process of modern design and research activity

    Directory of Open Access Journals (Sweden)

    Valova E. P.

    2017-10-01

    Full Text Available this article analyzes the theoretical prerequisites for the formation of communicative competences for the 8th and 9th grade students of the main school in the implementation of State educational standard of a basic general education. These competences are formed in the process of psychological and pedagogical support of the design and research activities of students. The author's experience in psychological and pedagogical support of contemporary design and research activities of the 8th and 9th grade students through their participation in competitions at various levels aimed at communicative competencies development, as well as preparation for choice of studies and further professional self-determination, is considered.

  14. The dosimetric standards for low and medium energy X-rays; Les references dosimetriques pour les rayons X de basses et moyennes energies

    Energy Technology Data Exchange (ETDEWEB)

    Ksouri, W.; Denoziere, M.; Lecerf, N.; Leroy, E.

    2009-07-01

    The Laboratoire national Henri Becquerel (LNE-LNHB) has developed national dosimetric standards for x-rays of low and medium energies. This article describes these standards which are aimed at applications of radiation protection of workers and patients in the fields of medical diagnosis and industrial x-ray radiation. Developments for contact radiotherapy are also discussed. (author)

  15. Ocean Sciences Sequence for Grades 6-8: Climate Change Curriculum Developed Through a Collaboration Between Scientists and Educators

    Science.gov (United States)

    Halversen, C.; Weiss, E. L.; Pedemonte, S.

    2016-02-01

    Today's youth have been tasked with the overwhelming job of addressing the world's climate future. The students who will become the scientists, policy makers, and citizens of tomorrow must gain a robust understanding of the causes and effects of climate change, as well as possible adaptation strategies. Currently, few high quality curriculum materials exist that address climate change in a developmentally appropriate manner. The NOAA-funded Ocean Sciences Sequence for Grades 6-8: The Ocean-Atmosphere Connection and Climate Change (OSS) addresses this gap by providing teachers with scientifically accurate climate change curriculum that hits on some of the most salient points in climate science, while simultaneously developing students' science process skills. OSS was developed through a collaboration between some of the nation's leading ocean and climate scientists and the Lawrence Hall of Science's highly qualified curriculum development team. Scientists were active partners throughout the entire development process, from initial brainstorming of key concepts and creating the conceptual storyline for the curriculum to final review of the content and activities. The goal was to focus strategically and effectively on core concepts within ocean and climate sciences that students should understand. OSS was designed in accordance with the latest research from the learning sciences and provides numerous opportunities for students to develop facility with science practices by "doing" science.Through hands-on activities, technology, informational readings, and embedded assessments, OSS deeply addresses a significant number of standards from the Next Generation Science Standards and is being used by many teachers as they explore the shifts required by NGSS. It also aligns with the Ocean Literacy and Climate Literacy Frameworks. OSS comprises 33 45-minute sessions organized into three thematic units, each driven by an exploratory question: (1) How do the ocean and atmosphere

  16. 'Odontologic dosimetric card' experiments and simulations using Monte Carlo methods

    International Nuclear Information System (INIS)

    Menezes, C.J.M.; Lima, R. de A.; Peixoto, J.E.; Vieira, J.W.

    2008-01-01

    The techniques for data processing, combined with the development of fast and more powerful computers, makes the Monte Carlo methods one of the most widely used tools in the radiation transport simulation. For applications in diagnostic radiology, this method generally uses anthropomorphic phantoms to evaluate the absorbed dose to patients during exposure. In this paper, some Monte Carlo techniques were used to simulation of a testing device designed for intra-oral X-ray equipment performance evaluation called Odontologic Dosimetric Card (CDO of 'Cartao Dosimetrico Odontologico' in Portuguese) for different thermoluminescent detectors. This paper used two computational models of exposition RXD/EGS4 and CDO/EGS4. In the first model, the simulation results are compared with experimental data obtained in the similar conditions. The second model, it presents the same characteristics of the testing device studied (CDO). For the irradiations, the X-ray spectra were generated by the IPEM report number 78, spectrum processor. The attenuated spectrum was obtained for IEC 61267 qualities and various additional filters for a Pantak 320 X-ray industrial equipment. The results obtained for the study of the copper filters used in the determination of the kVp were compared with experimental data, validating the model proposed for the characterization of the CDO. The results shower of the CDO will be utilized in quality assurance programs in order to guarantee that the equipment fulfill the requirements of the Norm SVS No. 453/98 MS (Brazil) 'Directives of Radiation Protection in Medical and Dental Radiodiagnostic'. We conclude that the EGS4 is a suitable code Monte Carlo to simulate thermoluminescent dosimeters and experimental procedures employed in the routine of the quality control laboratory in diagnostic radiology. (author)

  17. Development and Technology of Large Thickness TMCP Steel Plate with 390MPA Grade Used for Engineering Machinery

    Science.gov (United States)

    Wang, Xiaoshu; Zhang, Zhijun; Zhang, Peng

    Recently, with the rapid upgrading of the equipment in the steel Corp, the rolling technology of TMCP has been rapidly developed and widely applied. A large amount of steel plate has been produced by using the TMCP technology. The TMCP processes have been used more and more widely and replaced the heat treatment technology of normalizing, quenching and tempering heat process. In this paper, low financial input is considered in steel plate production and the composition of the steel has been designed with low C component, a limited alloy element of the Nb, and certain amounts of Mn element. During the continuous casting process, the size of the continuous casting slab section is 300 mm × 2400 mm. The rolling technology of TMCP is controlled at a lower rolling and red temperature to control the transformation of the microstructure. Four different rolling treatments are chosen to test its effects on the 390MPa grade low carbon steel of bainitic microstructure and properties. This test manages to produce a proper steel plate fulfilling the standard mechanical properties. Specifically, low carbon bainite is observed in the microstructure of the steel plate and the maximum thickness of steel plate under this TMCP technology is up to 80mm. The mechanical property of the steel plate is excellent and the KV2 at -40 °C performs more than 200 J. Moreover, the production costs are greatly reduced when the steel plate is produced by this TMCP technology when replacing the current production process of quenching and tempering. The low cost steel plate could well meet the requirements of producing engineering machinery in the steel market.

  18. Mechanical and dosimetric quality control for computer controlled radiotherapy treatment equipment.

    Science.gov (United States)

    Thompson, A V; Lam, K L; Balter, J M; McShan, D L; Martel, M K; Weaver, T A; Fraass, B A; Ten Haken, R K

    1995-05-01

    Modern computer controlled radiotherapy treatment equipment offers the possibility of delivering complex, multiple field treatments with minimal operator intervention, thus making multiple field conformal therapy practical. Conventional quality control programs are inadequate for this new technology, so new quality control procedures are needed. A reasonably fast, sensitive, and complete daily quality control program has been developed in our clinic that includes nearly automated mechanical as well as dosimetric tests. Automated delivery of these quality control fields is performed by the control system of the MM50 racetrack microtron, directed by the CCRS sequence processor [D. L. McShan and B. A. Fraass, Proceedings of the XIth International Conference on the use of computers in Radiation Therapy, 20-24 March 1994, Manchester, U.K. (North Western Medical Physics Department, Manchester, U.K., 1994), pp. 210-211], which controls the treatment process. The mechanical tests involve multiple irradiations of a single film to check the accuracy and reproducibility of the computer controlled setup of gantry and collimator angles, table orientation, collimator jaws, and multileaf collimator shape. The dosimetric tests, which involve multiple irradiations of an array of ionization chambers in a commercial dose detector (Keithly model 90100 Tracker System) rigidly attached to the head of the treatment gantry, check the output and symmetry of the treatment unit as a function of gantry and collimator angle and other parameters. For each of the dosimetric tests, readings from the five ionization chambers are automatically read out, stored, and analyzed by the computer, along with the geometric parameters of the treatment unit for that beam.(ABSTRACT TRUNCATED AT 250 WORDS)

  19. Dosimetry through the Secondary Laboratory of Dosimetric Calibration of Mexico

    International Nuclear Information System (INIS)

    Tovar M, V.M.; Alvarez R, J.T.; Medina O, V.P.; Vergara M, F.; Anaya M, R.; Cejudo A, J.; Salinas L, B.

    2004-01-01

    In the beginnings of the sixty years an urgent necessity is presented mainly in the developing countries, of improving in important form the accuracy in the dosimetry of external faces in therapy of radiations (radiotherapy centers), mainly in the calibration of c linical dosemeters . In 1976 the International Atomic Energy Agency, (IAEA), and the World Health Organization, (WHO), they carried out a mutual agreement with regard to the establishment and operation of a net of Secondary Patron Laboratories of Dosimetry, (LSCD). The necessity to establish measure patterns in the field of the dosimetry of the ionizing radiations, is necessary, to have an accuracy but high in the dosimetry of the radiation beams in therapy which is highly dependent of the dose given to the tumor of those patient with cancer. Similar levels of accuracy are required in protection measures to the radiation with an acceptable smaller accuracy, however, when the personal dosemeters are used to determine the doses received by the individuals under work conditions, such mensurations in therapy of radiations and radiological protection will have traceability through a chain of comparisons to primary or national patterns. The traceability is necessary to assure the accuracy and acceptability of the dosimetric measures, as well as, the legal and economic implications. The traceability is also necessary in the dosimetry of high dose like in the sterilization of different products. The main function of the LSCD is to provide a service in metrology of ionizing radiations, maintaining the secondary or national patterns, which have a traceability to the International System of measures, which is based for if same in the comparison of patterns in the Primary Laboratories of Dosimetry (LPD) under the auspice of the International Office of Weights and Measure (BIPM). The secondary and national patterns in the LSCD constitute in Mexico, the national patterns of the magnitudes in the dosimetry of the

  20. Low cost solar array project: Experimental process system development unit for producing semiconductor-grade silicon using silane-to-silicon process

    Science.gov (United States)

    1980-01-01

    The design, fabrication, and installation of an experimental process system development unit (EPSDU) were analyzed. Supporting research and development were performed to provide an information data base usable for the EPSDU and for technological design and economical analysis for potential scale-up of the process. Iterative economic analyses were conducted for the estimated product cost for the production of semiconductor grade silicon in a facility capable of producing 1000-MT/Yr.

  1. Child-centered versus teacher-directed teaching practices: Associations with the development of academic skills in the first grade at school

    OpenAIRE

    Lerkkanen, Marja-Kristiina; Kiuru, Noona; Pakarinen, Eija; Poikkeus, Anna-Maija; Rasku-Puttonen, Helena; Siekkinen, Martti; Nurmi, Jari-Erik

    2016-01-01

    This study examined the extent to which child-centered versus teacher-directed teaching practices predicted the development of children’s reading and math skills in the first year of elementary school. In addition, we investigated whether associations between teaching practices and children’s academic skills development in Grade 1 differed among children who had low, average, or high initial academic skills at the beginning of school. The reading and math skills of 1,132 Finnish c...

  2. Recognition of the dosimetric calibration capacities of Cuba by the International Bureau of Weights and Measures

    International Nuclear Information System (INIS)

    Walwyn S, G.; Gutierrez L, S.; Tamayo G, J.A.; Gonzalez R, N.; Alonso V, G.

    2006-01-01

    The declared mission of the International Bureau of Weights and Measures are the world uniformity of the measurement, however until some years ago a formal mechanism didn't exist for its complete implementation. With this end arose the Mutual Recognition Agreement whose specific objective is to establish the grade of equivalence of the national standards, the one of mutually recognizing the calibration and measurement certificates and the one of providing to the governments of a sure technical tool in its commercial negotiations and regulatory matters at international level. Cuba like an associated country to the Meter Convention, signed the agreement and it intended to demonstrate the international equivalence of its standards. The best measurement and calibration capacities of the country in the dosimetric magnitudes are in the Secondary Laboratory of Dosimetric Calibration of the Protection and Hygiene of Radiations Center. This capacities were included in the Regional Metrological Organization COOMET in the year 2003. In June of the 2005 the metrological capacities have been approved and published in the databases of the International Bureau of Weights and Measures as demonstration of the high competition of the calibration works that its are carried out in the laboratory. This approval is one of the maximum international recognitions that the patterns of a country can receive and its are the result of 10 years of work of the laboratory like part of the international net OIEA/OMS, which has given it the possibility to gauge the patterns and of adopting internationally validated calibration methodologies. On the other hand, it has been decisive the participation of the laboratory in multiple international comparisons of their patterns, as well as the implementation of a system of administration of the quality credited by the competent national organ. The article reviews the technical work of the laboratory during several years that it gave as result this

  3. Adjuvant Proton Beam Therapy in the Management of Thymoma: A Dosimetric Comparison and Acute Toxicities.

    Science.gov (United States)

    Parikh, Rahul R; Rhome, Ryan; Hug, Eugen; Tsai, Henry; Cahlon, Oren; Chon, Brian; Goenka, Anuj

    2016-09-01

    We evaluated the dosimetric differences between proton beam therapy (PBT) and intensity modulated radiation therapy (IMRT) for resected thymoma. We simultaneously report our early clinical experience with PBT in this cohort. We identified 4 patients with thymoma or thymic carcinoma treated at our center from 2012 to 2014 who completed adjuvant PBT to a median dose of 57.0 cobalt Gy equivalents (CGE; range, 50.4-66.6 CGE) after definitive resection. Adjuvant radiation was indicated for positive (n = 3) or close margin (n = 1). Median age was 45 (range, 32-70) years. Stages included II (n = 2), III (n = 1), and IVA (n = 1). Analogous IMRT plans were generated for each patient for comparison, and preset dosimetric endpoints were evaluated. Early toxicities were assessed according to retrospective chart review. Compared with IMRT, PBT was associated with lower mean doses to the lung (4.6 vs. 8.1 Gy; P = .02), esophagus (5.4 vs. 20.6 Gy; P = .003), and heart (6.0 vs. 10.4 Gy; P = .007). Percentages of lung, esophagus, and heart receiving radiation were consistently lower in the PBT plans over a wide range of radiation doses. There was no difference in mean breast dose (2.68 vs. 3.01 Gy; P = .37). Of the 4 patients treated with PBT, 3 patients experienced Grade 1 radiation dermatitis, and 1 patient experienced Grade 2 dermatitis, which resolved after treatment. With a median follow-up of 5.5 months, there were no additional Grade ≥ 2 acute or subacute toxicities, including radiation pneumonitis. PBT is clinically well tolerated after surgical resection of thymoma, and is associated with a significant reduction in dose to critical structures without compromising coverage of the target volume. Prospective evaluation and longer follow-up is needed to assess clinical outcomes and late toxicities. Copyright © 2016 Elsevier Inc. All rights reserved.

  4. Narrative and Vocabulary Development of Bilingual Children From Kindergarten to First Grade: Developmental Changes and Associations Among English and Spanish Skills

    Science.gov (United States)

    Uccelli, Paola; Páez, Mariela M.

    2010-01-01

    Purpose Research has identified English oral language proficiency as being critical for bilingual students’ literacy development. This study examines developmental patterns and associations among oral vocabulary and narrative skills in a longitudinal sample of 24 Spanish/English bilingual children from low socioeconomic backgrounds so as to further our understanding of the development of oral proficiency. Method English and Spanish data were gathered using standardized vocabulary tests and narrative elicitation tasks provided to kindergartners and first graders. Narratives were coded for length using two measures of productivity and for quality at two levels: story score and language score. Descriptive, correlation, multivariate, and regression analyses were conducted. Results Significant gains from kindergarten to first grade were found for all English oral language measures. Despite showing improvements in English vocabulary, the majority of children continued to score below the monolingual mean in first grade. For English narrative productivity, total number of different words (TDW) proved to be a sensitive developmental measure in contrast to total number of words (TNW). In Spanish, significant gains were noted only for narrative story score. Kindergarten Spanish story scores predicted first-grade English narrative quality even when controlling for the effects of English vocabulary and English narrative productivity. First-grade Spanish narrative quality was best predicted by Spanish vocabulary. Implications The need for early assessment and monitoring of expressive vocabulary and oral narrative skills, and the potential contributions of Spanish story organization skills to English narrative performance in bilingual children from low socioeconomic families, are highlighted. PMID:17625049

  5. The Development and Production of a Functionally Graded Composite for Pb-Bi Service.Final report

    International Nuclear Information System (INIS)

    Ballinger, Ronald G.

    2011-01-01

    A material that resists lead-bismuth eutectic (LBE) attack and retains its strength at 700 C would be an enabling technology for LBE-cooled reactors. No single alloy currently exists that can economically meet the required performance criteria of high strength and corrosion resistance. A Functionally Graded Composite (FGC) was developed with layers engineered to perform these functions. F91 was chosen as the structural layer of the composite for its strength and radiation resistance. Fe-12Cr-2Si, an alloy developed from previous work in the Fe-Cr-Si system, was chosen as the corrosion-resistant cladding layer because of its chemical similarity to F91 and its superior corrosion resistance in both oxidizing and reducing environments. Fe-12Cr-2Si experienced minimal corrosion due to its self-passivation in oxidizing and reducing environments. Extrapolated corrosion rates are below one micron per year at 700 C. Corrosion of F91 was faster, but predictable and manageable. Diffusion studies showed that 17 microns of the cladding layer will be diffusionally diluted during the three year life of fuel cladding. 33 microns must be accounted for during the sixty year life of coolant piping. 5 cm coolant piping and 6.35 mm fuel cladding preforms were produced on a commercial scale by weld-overlaying Fe-12Cr-2Si onto F91 billets and co-extruding them. An ASME certified weld was performed followed by the prescribed quench-and-tempering heat treatment for F91. A minimal heat affected zone was observed, demonstrating field weldability. Finally, corrosion tests were performed on the fabricated FGC at 700 C after completely breaching the cladding in a small area to induce galvanic corrosion at the interface. None was observed. This FGC has significant impacts on LBE reactor design. The increases in outlet temperature and coolant velocity allow a large increase in power density, leading to either a smaller core for the same power rating or more power output for the same size core

  6. Automatic 2D scintillation camera and computed tomography whole-body image registration to perform dosimetric calculations

    International Nuclear Information System (INIS)

    Cismondi, F.; Mosconi, S.L.

    2008-01-01

    Full text: In this work a software tool that has been developed to allow automatic registrations of 2D Scintillation Camera (SC) and Computed Tomography (CT) images is presented. This tool, used with a dosimetric software with Integrated Activity or Residence Time as input data, allows the user to assess physicians about effects of radiodiagnostic or radiotherapeutic practices that involves nuclear medicine 'open sources'. Images are registered locally and globally, maximizing Mutual Information coefficient between regions been registered. In the regional case whole-body images are segmented into five regions: head, thorax, pelvis, left and right legs. Each region has its own registration parameters, which are optimized through Powell-Brent minimization method that 'maximizes' Mutual Information coefficient. This software tool allows the user to draw ROIs, input isotope characteristics and finally calculate Integrated Activity or Residence Time in one or many specific organ. These last values can be introduced in many dosimetric software to finally obtain Absorbed Dose values. (author)

  7. Graded Assessment in Vocational Education and Training: An Analysis of National Practice, Drivers and Areas for Policy Development.

    Science.gov (United States)

    Williams, Melanie; Bateman, Andrea

    Practices and policies regarding graded assessment in vocational education and training (VET) in Australia were examined. Data were collected through a literature review; focus groups involving approximately 120 stakeholders in 5 states; interviews with 49 representatives of registered training organizations (RTOs); and surveys of RTOs, students,…

  8. Multi-Grade Kindergarten Classrooms and Children's Academic Achievement, Executive Function, and Socio-Emotional Development

    Science.gov (United States)

    Ansari, Arya

    2017-01-01

    Using data from the Early Childhood Longitudinal Study Kindergarten Class of 2010-2011 (ECLS-K: 2011; n = 11,000), this study examined the developmental outcomes of 5-year-old children in multi-grade classrooms (combined pre-kindergarten and kindergarten classrooms serving 3-, 4-, and 5-year-olds) compared with 5-year-olds attending…

  9. Effects of formative assessments to develop self-regulation among sixth grade students: Results from a randomized controlled intervention

    NARCIS (Netherlands)

    Meusen-Beekman, Kelly; Joosten-ten Brinke, Desirée; Boshuizen, Els

    2018-01-01

    This article presents the results of a formative assessment intervention in writing assignments in sixth grade. We examined whether formative assessments would improve self-regulation, motivation and self-efficacy among sixth graders, and whether differential effects exist between formative

  10. Effects of Engineering Design-Based Science on Elementary School Science Students' Engineering Identity Development across Gender and Grade

    Science.gov (United States)

    Capobianco, Brenda M.; Yu, Ji H.; French, Brian F.

    2015-01-01

    The integration of engineering concepts and practices into elementary science education has become an emerging concern for science educators and practitioners, alike. Moreover, how children, specifically preadolescents (grades 1-5), engage in engineering design-based learning activities may help science educators and researchers learn more about…

  11. Historical revision of the exposure magnitude and the dosimetric magnitudes used in radiological protection

    International Nuclear Information System (INIS)

    Gonzalez J, F.; Alvarez R, J. T.

    2014-10-01

    In this work a historical revision of the exposure magnitude development and their roentgen unit (1905 - 2011) is made, noting that it had their origin in the electric methods for the detection of the ionizing radiation in the period of 1895 at 1937. However, the ionization is not who better characterizes the physical, chemical and biological effects of the ionizing radiations, but is the energy deposited by this radiation in the interest bodies, which led historically to the development of dosimetric magnitudes in energy terms like they are: the absorbed dose D (1950), the kerma K (1958) and the equivalent dose H (1962). These dosimetric magnitudes culminated with the definition of the effective equivalent dose or effective dose which is not measurable and should be considered with the operative magnitudes ICRU: H environmental equivalent dose and/or H directional equivalent dose, which can be determined by means of a conversion coefficient that is applied to the exposure, kerma in air, fluence, etc. (Author)

  12. DEVELOPMENT OF AN EMAT IN-LINE INSPECTION SYSTEM FOR DETECTION, DISCRIMINATION, AND GRADING OF STRESS CORROSION CRACKING IN PIPELINES

    Energy Technology Data Exchange (ETDEWEB)

    Jeff Aron; Jeff Jia; Bruce Vance; Wen Chang; Raymond Pohler; Jon Gore; Stuart Eaton; Adrian Bowles; Tim Jarman

    2005-02-01

    This report describes prototypes, measurements, and results for a project to develop a prototype pipeline in-line inspection (ILI) tool that uses electromagnetic acoustic transducers (EMATs) to detect and grade stress corrosion cracking (SCC). The introduction briefly provides motivation and describes SCC, gives some background on EMATs and guided ultrasonic waves, and reviews promising results of a previous project using EMATs for SCC. The experimental section then describes lab measurement techniques and equipment, the lab mouse and prototypes for a mule, and scan measurements made on SCC. The mouse was a moveable and compact EMAT setup. The prototypes were even more compact circuits intended to be pulled or used in an ILI tool. The purpose of the measurements was to determine the best modes, transduction, and processing to use, to characterize the transducers, and to prove EMATs and mule components could produce useful results. Next, the results section summarizes the measurements and describes the mouse scans, processing, prototype circuit operating parameters, and performance for SH0 scans. Results are given in terms of specifications--like SNR, power, insertion loss--and parametric curves--such as signal amplitude versus magnetic bias or standoff, reflection or transmission coefficients versus crack depth. Initially, lab results indicated magnetostrictive transducers using both SH0 and SV1 modes would be worthwhile to pursue in a practical ILI system. However, work with mule components showed that SV1 would be too dispersive, so SV1 was abandoned. The results showed that reflection measurements, when normalized by the direct arrival are sensitive to and correlated with SCC. This was not true for transmission measurements. Processing yields a high data reduction, almost 60 to 1, and permits A and C scan display techniques and software already in use for pipeline inspection. An analysis of actual SH0 scan results for SCC of known dimensions showed that length

  13. Dosimetric considerations and radiation protection of patients in interventional cardiology

    International Nuclear Information System (INIS)

    Ciraj-Bjelac, O.; Arandjic, D.; Kosutic, D.; Loncar, B.

    2009-01-01

    The paper summarizes results of measurements of relevant dosimetric quantities in interventional cardiology. Dosimetric data were collected for 117 coronary angiography (CA) procedures, 69 percutaneous coronary interventions (PCI) and 41 combined procedures (CA+PCI), taking into account two quantities: air kerma area product (KAP) d air kerma in international reference point (K IRP ). Mean KAP values were 78 Gy·cm 2 , 113 Gy·cm 2 and 141 Gy·cm 2 for CA, PCI i CA+PCI, respectively. Corresponding mean K IRP values were 1.2 Gy, 1.8 Gy and 2.2 Gy. With respect to high dose values, risk for stochastic effects and tissue reactions, dose management methods were proposed. (author) [sr

  14. Development of a compact electronic dosemeter from CMOS sensor for radon measurement; Developpement d'un dosimetre electronique compact a base de capteurs CMOS pour la mesure du radon

    Energy Technology Data Exchange (ETDEWEB)

    Higueret, St

    2007-12-15

    Radon detection is a long-standing challenge in the field of radioprotection, and the IPHC Institute of Strasbourg has pushed for the development of a fully electronic device, portable and really standalone. Our first prototype of CMOS system-on-chip is presented, together with efficiency tests and the corresponding physics simulations (TRIM, GEANT IV). We describe several electronic boards which have been developed for various kinds of tests, firstly passive detection of {alpha}-particles from gaseous {sup 222}Rn in a large spectrum of activity concentrations. In a second stage, active collection of the daughter isotopes {sup 218}Po and {sup 214}Po was performed: these elements, appearing as attached on the aerosols present in air, are an important contribution to internal {alpha}-irradiation. The final electronic system, of only 10 cm size, includes four independent chips to ensure simultaneous detection of radon gas and its aerosols. An excellent linearity has been measured up to 80 kBq.m{sup -3} on the BACCARA bench of the IRSN at Saclay. A new generation chip is also studied. (author)

  15. Development of a computational system based in the code GEANT4 for dosimetric evaluation in radiotherapy; Desenvolvimento de um sistema computacional baseado no Codigo GEANT4 para avaliacoes dosimetricas em radioterapia

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira, Alex Cristovao Holanda de

    2016-10-01

    The incidence of cancer has grown in Brazil, as well as around the world, following the change in the age profile of the population. One of the most important techniques and commonly used in cancer treatment is radiotherapy. Around 60% of new cases of cancer use radiation in at least one phase of treatment. The most used equipment for radiotherapy is a linear accelerator (Linac) which produces electron or X-ray beams in energy range from 5 to 30 MeV. The most appropriate way to irradiate a patient is determined during treatment planning. Currently, treatment planning system (TPS) is the main and the most important tool in the process of planning for radiotherapy. The main objective of this work is to develop a computational system based on the MC code Geant4 for dose evaluations in photon beam radiotherapy. In addition to treatment planning, these dose evaluations can be performed for research and quality control of equipment and TPSs. The computer system, called Quimera, consists of a graphical user interface (qGUI) and three MC applications (qLinacs, qMATphantoms and qNCTphantoms). The qGUI has the function of interface for the MC applications, by creating or editing the input files, running simulations and analyzing the results. The qLinacs is used for modeling and generation of Linac beams (phase space). The qMATphantoms and qNCTphantoms are used for dose calculations in virtual models of physical phantoms and computed tomography (CT) images, respectively. From manufacturer's data, models of a Varian Linac photon beam and a Varian multileaf collimator (MLC) were simulated in the qLinacs. The Linac and MLC modelling were validated using experimental data. qMATphamtoms and qNCTphantoms were validated using IAEA phase spaces. In this first version, the Quimera can be used for research, radiotherapy planning of simple treatments and quality control in photon beam radiotherapy. The MC applications work independent of the qGUI and the qGUI can be used for

  16. Development of NTCP models for head and neck cancer patients treated with three-dimensional conformal radiotherapy for xerostomia and sticky saliva: The role of dosimetric and clinical factors

    International Nuclear Information System (INIS)

    Beetz, Ivo; Schilstra, Cornelis; Burlage, Fred R.; Koken, Phil W.; Doornaert, Patricia; Bijl, Henk P.; Chouvalova, Olga; Leemans, C. René; Bock, Geertruida H. de; Christianen, Miranda E.M.C.; Laan, Bernard F.A.M. van der; Vissink, Arjan; Steenbakkers, Roel J.H.M.; Langendijk, Johannes A.

    2012-01-01

    Purpose: The purpose of this multicentre prospective study was to investigate the significance of the radiation dose in the major and minor salivary glands, and other pre-treatment and treatment factors, with regard to the development of patient-rated xerostomia and sticky saliva among head and neck cancer (HNC) patients treated with primary (chemo-) radiotherapy ((CH)RT). Methods and materials: The study population was composed of 167 consecutive HNC patients treated with three-dimensional conformal (3D-CRT) (CH) RT. The primary endpoint was moderate to severe xerostomia (XER6m) as assessed by the EORTC QLQ-H and N35 at 6 months after completing (CH)RT. The secondary endpoint was moderate to severe sticky saliva at 6 months (STIC6 m). All organs at risk (OARs) potentially involved in salivary function were delineated on planning-CT, including the parotid, submandibular and sublingual glands and the minor glands in the soft palate, cheeks and lips. Patients with moderate to severe xerostomia or sticky saliva at baseline were excluded. The optimum number of variables for a multivariate logistic regression model was determined using a bootstrapping method. Results: The multivariate analysis showed the mean parotid dose, age and baseline xerostomia (none versus a bit) to be the most important predictors for XER6m. The risk of developing xerostomia increased with age and was higher when minor baseline xerostomia was present in comparison with patients without any xerostomia complaints at baseline. Model performance was good with an area under the curve (AUC) of 0.82. For STIC6m, the mean submandibular dose, age, the mean sublingual dose and baseline sticky saliva (none versus a bit) were most predictive for sticky saliva. The risk of developing STIC6 m increased with age and was higher when minor baseline sticky saliva was present in comparison with patients without any sticky saliva complaints at baseline. Model performance was good with an AUC of 0.84. Conclusions

  17. Development of English and French Language and Literacy Skills in EL1 and EL French Immersion Students in the Early Grades

    Science.gov (United States)

    Au-Yeung, Karen; Hipfner-Boucher, Kathleen; Chen, Xi; Pasquarella, Adrian; D'Angelo, Nadia; Deacon, S. Hélène

    2015-01-01

    In this article, we report two studies that compared the development of English and French language and literacy skills in French immersion students identified as native English speakers (EL1s) and English learners (ELs). In study 1, 81 EL1s and 147 ELs were tested in the fall and spring terms of grade 1. The EL1s and ELs had similar outcomes and…

  18. Development of a dosimetric system for the quality control of breast cancer treatments; Desenvolvimento de um sistema dosimetrico para o controle de qualidade nos tratamentos de cancer de mama

    Energy Technology Data Exchange (ETDEWEB)

    Chaves, Roberio C.; Crispim, Verginia R., E-mail: rchaves@nuclear.ufrj.br, E-mail: verginia@nuclear.ufrj.br [Coordenacao dos Programas de Pos-Graduacao de Engenharia (PEN/COPPE/lUFRJ), RJ (Brazil). Programa de Pos-Graduacao em Engenharia Nuclear; Rosa, Luiz A.R. da, E-mail: Irosa@ird.gov.br [Instituto de Radioprotecao e Dosimetria (IRD/CNEN), Rio de Janeiro, RJ (Brazil); Santos, Delano B.V., E-mail: delano@inca.gov.br [Instituto Nacional do Cancer (INCA/MS), Rio de Janeiro, RJ (Brazil)

    2013-11-01

    A system for evaluating the values of absorbed dose in breast teletherapy was developed, using thermoluminescent dosimeters (TLD-100), to compare them to those provided by Therapy planning system. A breast phantom was made to distribute the dosimeters TL shaped chip in breast volume and irradiate it under the same conditions of planning. Three different techniques of teletherapy were considered: one with irradiation from a therapy unit of {sup 60}Co and two with an X-ray beam coming from a 6 MV linear accelerator. Doses measures allowed checking that the performance of the quality control system used in breast cancer treatment is appropriate, since the planned doses differed about 1.5% of the responses provided by TL dosimeters.

  19. Adding Ipsilateral V20 and V30 to Conventional Dosimetric Constraints Predicts Radiation Pneumonitis in Stage IIIA-B NSCLC Treated With Combined-Modality Therapy

    International Nuclear Information System (INIS)

    Ramella, Sara; Trodella, Lucio; Mineo, Tommaso Claudio; Pompeo, Eugenio; Stimato, Gerardina; Gaudino, Diego; Valentini, Vincenzo; Cellini, Francesco; Ciresa, Marzia; Fiore, Michele; Piermattei, Angelo; Russo, Patrizia; Cesario, Alfredo; D'Angelillo, Rolando M.

    2010-01-01

    Purpose: To determine lung dosimetric constraints that correlate with radiation pneumonitis in non-small-cell lung cancer patients treated with three-dimensional radiation therapy and concurrent chemotherapy. Methods and Materials: Between June 2002 and December 2006, 97 patients with locally advanced non-small-cell lung cancer were treated with concomitant radiochemotherapy. All patients underwent complete three-dimensional treatment planning (including dose-volume histograms), and patients were treated only if the percentage of total lung volume exceeding 20 Gy (V 20 ) and 30 Gy (V 30 ), and mean lung dose (MLD) had not exceeded the constraints of 31%, 18%, and 20 Gy, respectively. The total and ipsilateral lung dose-volume histogram parameters, planning target volume, and total dose delivered were analyzed and correlated with pneumonitis incidence. Results: If dose constraints to the total lung were respected, the most statistically significant factors predicting pneumonitis were the percentage of ipsilateral lung volume exceeding 20 Gy (V 20 ipsi), percentage of ipsilateral lung volume exceeding 30 Gy (V 30 ipsi), and planning target volume. These parameters divided the patients into low- and high-risk groups: if V 20 ipsi was 52% or lower, the risk of pneumonitis was 9%, and if V 20 ipsi was greater than 52%, the risk of pneumonitis was 46%; if V 30 ipsi was 39% or lower, the risk of pneumonitis was 8%, and if V 30 ipsi was greater than 39%, the risk of pneumonitis was 38%. Actuarial curves of the development of pneumonitis of Grade 2 or higher stratified by V 20 ipsi and V 30 ipsi were created. Conclusions: The correlation between pneumonitis and dosimetric constraints has been validated. Adding V 20 ipsi and V 30 ipsi to the classical total lung constraints could reduce pulmonary toxicity in concurrent chemoradiation treatment. V 20 ipsi and V 30 ipsi are important if the V 20 to the total lung, V 30 to the total lung, and mean lung dose have not exceeded

  20. Use of TLD-100 to verify a dosimetric method for total electron skin irradiation

    International Nuclear Information System (INIS)

    Mesa, F.; Sosa, M.

    2007-01-01

    Full text: A clinical dosimetric method for generating a homogeneous field of radiation around of patients under treatment of total skin electron irradiation and its verification using thermoluminescent dosimetry is presented. The irradiations were performed utilizing a 6 MeV electron beam generated by a Varian Clinac 21EX linear accelerator installed in the oncology unit of the IMSS-Tl hospital in Leon. Levels of radiation for diverse adjustment performed in the treatment planning system of the lineal accelerator and registered to different treatment distances using a computerized water phantom system were studied. A large batch of TLD-100 chips calibrated in terms of air-kerma rate to the standard treatment distance and positioned in an anthropomorphic Alderson Random Phantom was used. Dose verification and comparison with the measurements made with the computerized system were analyzed. A single field electron beam for treatment of total skin irradiation was implemented. Preliminary results indicate that the levels of dose homogeneities were larger than 90% for distances up to 3.0 m. The results suggest that the method developed is a reliable for delivering an electron beam with significantly homogeneity for these treatments. Analyses and results of both thermoluminescent and computerized dosimetric system calibrations are also presented. (Author)

  1. A Combined Tissue Kinetics and Dosimetric Model of Respiratory Tissue Exposed to Radiation

    Energy Technology Data Exchange (ETDEWEB)

    John R. Ford

    2005-11-01

    Existing dosimetric models of the radiation response of tissues are essentially static. Consideration of changes in the cell populations over time has not been addressed realistically. For a single acute dose this is not a concern, but for modeling chronic exposures or fractionated acute exposures, the natural turnover and progression of cells could have a significant impact on a variety of endpoints. This proposal addresses the shortcomings of current methods by combining current dose-based calculation techniques with information on the cell turnover for a model tissue. The proposed model will examine effects at the single-cell level for an exposure of a section of human bronchiole. The cell model will be combined with Monte Carlo calculations of doses to cells and cell nuclei due to varying dose-rates of different radiation qualities. Predictions from the model of effects on survival, apoptosis rates, and changes in the number of cycling and differentiating cells will be tested experimentally. The availability of dynamic dosimetric models of tissues at the single-cell level will be useful for analysis of low-level radiation exposures and in the development of new radiotherapy protocols.

  2. Recovery of α-Al{sub 2}O{sub 3} from ionizing radiation dosimetric sensors

    Energy Technology Data Exchange (ETDEWEB)

    Sanches, Edgar Aparecido, E-mail: sanches.ufam@gmail.com [Universidade Federal do Amazonas (UFAM), Manaus, AM (Brazil). Dept. de Fisica; Costalonga, Ademir Geraldo Cavallari; Mascarenhas, Yvonne Primerano [Universidade de Sao Paulo (IFSC/USP), Sao Carlos, SP (Brazil). Institute de Fisica; Nascimento, Luana de Freitas [Belgium Nuclear Research Centre, SCK-CEN, Mol (Belgium); Mascarenhas, Yvone Maria [SAPRA S/A Servico de Assessoria e Protecao Radiologica, Sao Carlos, SP, (Brazil)

    2015-01-15

    Corundum, sapphire or α-Al{sub 2}O{sub 3} is an important technological material in many optical and electronic applications such as solid-state lasers, optical windows and, more recently, as a radiation detector. Landauer (Glenwood, IL, USA) accumulated large number of archived and stored Luxel™ dosemeters composed of Al{sub 2}O{sub 3}:C, which were subjected to a recovery process. Due to the importance of this advanced crystalline material in OSL dosimetry, a recovery process was developed based on the dosemeters calcination and Al{sub 2}O{sub 3}:C has been reused in manufacturing of new dosemeters. This paper does not aim to optimize the recovery process, but provides an opportunity to study the involved process parameters and to recover this valuable crystalline material from used dosemeters. To the best of our knowledge no other recovery process involving this dosimetric material was described in scientific literature. Fourier Transform Infrared Spectrometry (FTIR), Thermogravimetry/Differential Thermoanalysis (TG/DTA), Differential Scanning Calorimetry (DSC), X-ray Diffraction (XRD), Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES), Optically Stimulated Luminescence (OSL) and Rietveld Refinement were used to characterize the recovered material and to check for the stability of its structural and dosimetric properties. (author)

  3. Dosimetric improvements following 3D planning of tangential breast irradiation

    International Nuclear Information System (INIS)

    Aref, Amr; Thornton, Dale; Youssef, Emad; He, Tony; Tekyi-Mensah, Samuel; Denton, Lori; Ezzell, Gary

    2000-01-01

    Purpose: To evaluate the dosimetric difference between a simple radiation therapy plan utilizing a single contour and a more complex three-dimensional (3D) plan utilizing multiple contours, lung inhomogeneity correction, and dose-based compensators. Methods and Materials: This is a study of the radiation therapy (RT) plans of 85 patients with early breast cancer. All patients were considered for breast-conserving management and treated by conventional tangential fields technique. Two plans were generated for each patient. The first RT plan was based on a single contour taken at the central axis and utilized two wedges. The second RT plan was generated by using the 3D planning system to design dose-based compensators after lung inhomogeneity correction had been made. The endpoints of the study were the comparison between the volumes receiving greater than 105% and greater than 110% of the reference dose, as well as the magnitude of the treated volume maximum dose. Dosimetric improvement was defined to be of significant value if the volume receiving > 105% of one plan was reduced by at least 50% with the absolute difference between the volumes being 5% or greater. The dosimetric improvements in 49 3D plans (58%) were considered of significant value. Patients' field separation and breast size did not predict the magnitude of improvement in dosimetry. Conclusion: Dose-based compensator plans significantly reduced the volumes receiving > 105%, >110%, and volume maximum dose.

  4. Gamma dosimetric parameters in some skeletal muscle relaxants

    Science.gov (United States)

    Manjunatha, H. C.

    2017-09-01

    We have studied the attenuation of gamma radiation of energy ranging from 84 keV to 1330 keV (^{170}Tm, ^{22}Na,^{137}Cs, and ^{60}Co) in some commonly used skeletal muscle relaxants such as tubocurarine chloride, gallamine triethiodide, pancuronium bromide, suxamethonium bromide and mephenesin. The mass attenuation coefficient is measured from the attenuation experiment. In the present work, we have also proposed the direct relation between mass attenuation coefficient (μ /ρ ) and mass energy absorption coefficient (μ _{en}/ρ ) based on the nonlinear fitting procedure. The gamma dosimetric parameters such as mass energy absorption coefficient (μ _{en}/ρ ), effective atomic number (Z_{eff}), effective electron density (N_{el}), specific γ-ray constant, air kerma strength and dose rate are evaluated from the measured mass attentuation coefficient. These measured gamma dosimetric parameters are compared with the theoretical values. The measured values agree with the theoretical values. The studied gamma dosimetric values for the relaxants are useful in medical physics and radiation medicine.

  5. Effective atomic numbers and electron density of dosimetric material

    Directory of Open Access Journals (Sweden)

    Kaginelli S

    2009-01-01

    Full Text Available A novel method for determination of mass attenuation coefficient of x-rays employing NaI (Tl detector system and radioactive sources is described.in this paper. A rigid geometry arrangement and gating of the spectrometer at FWHM position and selection of absorber foils are all done following detailed investigation, to minimize the effect of small angle scattering and multiple scattering on the mass attenuation coefficient, m/r, value. Firstly, for standardization purposes the mass attenuation coefficients of elemental foils such as Aluminum, Copper, Molybdenum, Tantalum and Lead are measured and then, this method is utilized for dosimetric interested material (sulfates. The experimental mass attenuation coefficient values are compared with the theoretical values to find good agreement between the theory and experiment within one to two per cent. The effective atomic numbers of the biological substitute material are calculated by sum rule and from the graph. The electron density of dosimetric material is calculated using the effective atomic number. The study has discussed in detail the attenuation coefficient, effective atomic number and electron density of dosimetric material/biological substitutes.

  6. SU-F-BRB-15: Dosimetric Study of Radiation Therapy for Head/Neck Patients with Metallic Dental Fixtures

    Energy Technology Data Exchange (ETDEWEB)

    Lu, L; Allan, E; Putten, M Van; Gupta, N; Blakaj, D [OH State University, Columbus, OH (United States)

    2015-06-15

    Purpose: To investigate the dose contributions of scattered electrons from dental amalgams during head and neck radiotherapy, and to evaluate the protective role of dosimetric dental stents during treatment to prevent oral mucositis. Methods: A phantom was produced to accurately simulate the oral cavity and head. The oral cavity consisted of a tissue equivalent upper and lower jaw and complete set of teeth. A set of 4 mm ethylene copolymer dosimetric stents was made for the upper and lower teeth. Five removable gold caps were fitted to apposing right molars, and the phantom was crafted to accomodate horizontal and vertical film for 2D dosimetry and NanoDot dosimeter for recording point doses. The head was simulated using a small cylindrical glass water bath. CT simulation was performed on the phantom with and without metal fittings and, in each case, with and without the dental stent. The CT image sets were imported into Eclipse treatment planning system for contouring and treatment planning, and a 9-field IMRT treatment plan was developed for each scenario. These plans were delivered using a Varian TrueBeam linear accelerator. Doses were recorded using GafChromic EBT2 films and NanoDot dosimeters. Results: The measurements revealed a 43% relative increase in dose measured adjacent to the metal fixtures in the horizontal plane without the use of the dental stent. This equates to a total dose of 100 Gy to the oral mucosa during a standard course of definitive radiotherapy. To our knowledge, this is the first dosimetric analysis of dental stents using an anatomically realistic phantom and modern beam arrangement. Conclusion: These results support the use of dosimetric dental stents in head and neck radiotherapy for patients with metallic dental fixtures as a way to effectively reduce dose to nearby mucosal surfaces and, hence, reduce the risk and severity of mucositis.

  7. A prospective study on radiation pneumonitis following conformal radiation therapy in non-small-cell lung cancer: clinical and dosimetric factors analysis.

    Science.gov (United States)

    Claude, Line; Pérol, David; Ginestet, Chantal; Falchero, Lionel; Arpin, Dominique; Vincent, Michel; Martel, Isabelle; Hominal, Stéphane; Cordier, Jean-François; Carrie, Christian

    2004-05-01

    Clinical and dosimetric prognostic factors for radiation pneumonitis (RP) have been reported after three-dimensional conformal radiotherapy (3D-CRT) in patients with non-small cell lung cancer (NSCLC). Ninety-six patients who received 3D-CRT for stage IA to IIIB NSCLC were evaluated prospectively. Surgery was performed before radiation in 51% of the patients (n = 49). RP was diagnosed six-eight weeks after 3D-CRT using the Lent-Soma classification. Factors evaluated included treatment factors such as total mean lung dose (MLD), and dose-volume histogram (DVH) thresholds for several radiation dose steps. These thresholds were originally determined from the median of the irradiated lung volume at each step. Six patients could not be evaluated for RP six weeks after 3D-CRT. Of the 90 remaining patients, 40 (44%) had RP (i.e. grade > or =1) at 6 weeks, including 7 patients (7.8%) with severe RP (grade > or =2). Regarding the whole toxicity (grade > or =1), age (> or =60 years), MLD, V20 and V30 were significantly related to RP. DVH thresholds determined for radiation doses from 20 to 40 Gy were also predictive of RP. Considering only severe RP (grade > or =2), only MLD, V20 and V30 remained associated with increased acute pulmonary toxicity. In this study, dosimetric factors (MLD, V20, V30) and age (> or =60 years) were predictive of RP regarding the whole pulmonary toxicity (grade > or =1). In addition, thresholds from 20 to 40 Gy, based on a stratification according to the median of the percentage of irradiated lung volume, were also predictive factors. They may, therefore, help discriminate patients at high and low risk for RP. However, only MLD, V20 and V30 remained associated with severe RP (grade > or =2), probably due to the small number of severe events in our series.

  8. Development, properties, processing and applications of high-silicon steel grade X2CrNiSi 1815

    International Nuclear Information System (INIS)

    Horn, E.M.

    1977-01-01

    A significant corrosion resistance to highly concentrated nitric acid in combination with good workability and weldability can be achieved by an austenitic chromium-nickel steel alloyed with silicon. For corrosion considerations a silicon contents of at least 3.7 wt.% has to be aimed at. Since the silicon is held in solid solution in the austenitic matrix, the mechanical properties of the special grade X2CrNiSi 1815 are not very different from those of commercial chromium-nickel steel grades. Welding materials of the same kind are available for manual arc welding as well as for TIG welding. The corrosion resultance of the weld deposit is similar to that of the base metal. However, the tendency of this steel to precipitate intermetallic phases is increased by the silicon addition. There, a proper heat control during welding is a necessary prerequisite in order to avoid intercrystalline attack in the heat-affected zones on both sides of the weld. A silicon contents of approximately 4 wt.% not only improves the corrosion resistance against highly concentrated nitric acid but also results in a considerable improvement when this special steel is used in chromic acid solutions and hot concentrated sulfuric acid. Also the high temperature corrosion resistance of this material is remarkable. Several piping systems, chemical equipment, pumps, and fittings have been in successfull service for several years and proved the excellent properties of the X2CrNiSi 1815 specially steel. (orig.) [de

  9. MOOC and mechanized grading

    OpenAIRE

    Queinnec, Christian

    2013-01-01

    4 pages; As many others, we too are developping a Massive Online Open Course or MOOC. This MOOC will teach recursive programming for beginnners and makes an heavy use of an already existing infrastructure for mechanical grading. This paper presents some ideas on how to combine these two components along with some (untested) incentives in order to increase students' involvement.

  10. Development of Analytical Reading Skill on Soonthornphu’s Literary Works Using Drills with STAD Cooperative Learning Process for Grade 7 Students

    Directory of Open Access Journals (Sweden)

    Pannapong Thunapan

    2017-06-01

    Full Text Available The development of the analytical reading skill on Soonthornphu’s literary works using drills with STAD cooperative learning process aimied to: 1 develop the analytical reading ability on Soonthornphu’s literary works using drills with STAD cooperative learning process ; 2 develop drills of analytical reading on Soonthornphu’s literary works using drills with STAD cooperative learning process to meet the 80/80 efficiency criterion ; 3 compare the analytical reading learning achievements, before and after learning using drills with STAD cooperative learning process ; 4 find the effectiveness index of the students after the development of the analytical reading ability on Soonthornphu’s literary works using drills with STAD cooperative learning process. The sample comprised 32 grade 7 students from Group 2 of Thakhonyangpittayakhom School, Kantarawichai District, Mahasarakham Province, in the 2nd semester of the academic year 2015, obtained through cluster sampling, using the class as the sampling unit. The instruments were of 4 types: learning organization plans with the quality in the high level ; 6 drills of analytical reading ; a 4-choice learning achievement test of analytical reading containing 30 questions, and a subjective test containing 3 questions, having the discrimination from 0.25 to 0.83 and the total reliability of 0.84 ; an evaluation form for analytical reading skill, and a 5-level satisfaction rating scale questionnaire containing 15 questions which had been examined by experts. The statistics employed in data analysis were percentage, the mean, standard deviation, and t-test (dependent samples for hypothesis testing. The results revealed that the grade 7 students whose analytical reading skill on Soonthornphu’s literary works using drills with STAD cooperative learning process was developed had their analytical reading skill in the good level ; the drills of analytical reading skill had the efficiency of 85

  11. Methods of graded rings

    CERN Document Server

    Nastasescu, Constantin

    2004-01-01

    The topic of this book, graded algebra, has developed in the past decade to a vast subject with new applications in noncommutative geometry and physics. Classical aspects relating to group actions and gradings have been complemented by new insights stemming from Hopf algebra theory. Old and new methods are presented in full detail and in a self-contained way. Graduate students as well as researchers in algebra, geometry, will find in this book a useful toolbox. Exercises, with hints for solution, provide a direct link to recent research publications. The book is suitable for courses on Master level or textbook for seminars.

  12. Predicting Nonauditory Adverse Radiation Effects Following Radiosurgery for Vestibular Schwannoma: A Volume and Dosimetric Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Hayhurst, Caroline; Monsalves, Eric; Bernstein, Mark; Gentili, Fred [Gamma Knife Unit, Division of Neurosurgery, University Health Network, Toronto (Canada); Heydarian, Mostafa; Tsao, May [Radiation Medicine Program, Princess Margaret Hospital, Toronto (Canada); Schwartz, Michael [Radiation Oncology Program and Division of Neurosurgery, Sunnybrook Hospital, Toronto (Canada); Prooijen, Monique van [Radiation Medicine Program, Princess Margaret Hospital, Toronto (Canada); Millar, Barbara-Ann; Menard, Cynthia [Radiation Oncology Program, Princess Margaret Hospital, Toronto (Canada); Kulkarni, Abhaya V. [Division of Neurosurgery, Hospital for Sick Children, University of Toronto (Canada); Laperriere, Norm [Radiation Oncology Program, Princess Margaret Hospital, Toronto (Canada); Zadeh, Gelareh, E-mail: Gelareh.Zadeh@uhn.on.ca [Gamma Knife Unit, Division of Neurosurgery, University Health Network, Toronto (Canada)

    2012-04-01

    Purpose: To define clinical and dosimetric predictors of nonauditory adverse radiation effects after radiosurgery for vestibular schwannoma treated with a 12 Gy prescription dose. Methods: We retrospectively reviewed our experience of vestibular schwannoma patients treated between September 2005 and December 2009. Two hundred patients were treated at a 12 Gy prescription dose; 80 had complete clinical and radiological follow-up for at least 24 months (median, 28.5 months). All treatment plans were reviewed for target volume and dosimetry characteristics; gradient index; homogeneity index, defined as the maximum dose in the treatment volume divided by the prescription dose; conformity index; brainstem; and trigeminal nerve dose. All adverse radiation effects (ARE) were recorded. Because the intent of our study was to focus on the nonauditory adverse effects, hearing outcome was not evaluated in this study. Results: Twenty-seven (33.8%) patients developed ARE, 5 (6%) developed hydrocephalus, 10 (12.5%) reported new ataxia, 17 (21%) developed trigeminal dysfunction, 3 (3.75%) had facial weakness, and 1 patient developed hemifacial spasm. The development of edema within the pons was significantly associated with ARE (p = 0.001). On multivariate analysis, only target volume is a significant predictor of ARE (p = 0.001). There is a target volume threshold of 5 cm3, above which ARE are more likely. The treatment plan dosimetric characteristics are not associated with ARE, although the maximum dose to the 5th nerve is a significant predictor of trigeminal dysfunction, with a threshold of 9 Gy. The overall 2-year tumor control rate was 96%. Conclusions: Target volume is the most important predictor of adverse radiation effects, and we identified the significant treatment volume threshold to be 5 cm3. We also established through our series that the maximum tolerable dose to the 5th nerve is 9 Gy.

  13. Practical guide. Realisation of dosimetric studies for workplaces exhibiting a ionizing radiation exposure risk (version 4)

    International Nuclear Information System (INIS)

    2015-01-01

    This guide proposes a methodological approach to help carry out dosimetric workplace studies complying with the French regulation, and necessary to identify risks of radiological exposure, optimize radiation protection and classify the workers into different categories. Additional information is provided relating the main objectives of a workplace study, the French regulatory context, main sources and pathways of exposure to ionizing radiation. Radiation protection and operational quantities are reminded. Recommendations about the selection and use of detectors and about the implementation of calculation methods are also provided. The general methodological approach is applied and developed into 'workplace sheets', each one devoted to a particular type of workplace. Up to now only sheets related to medical field have been developed. By extension, advices for classify the workplaces into different areas are also supplied. (authors)

  14. Development of processes for the production of solar grade silicon from halides and alkali metals, phase 1 and phase 2

    Science.gov (United States)

    Dickson, C. R.; Gould, R. K.; Felder, W.

    1981-01-01

    High temperature reactions of silicon halides with alkali metals for the production of solar grade silicon are described. Product separation and collection processes were evaluated, measure heat release parameters for scaling purposes and effects of reactants and/or products on materials of reactor construction were determined, and preliminary engineering and economic analysis of a scaled up process were made. The feasibility of the basic process to make and collect silicon was demonstrated. The jet impaction/separation process was demonstrated to be a purification process. The rate at which gas phase species from silicon particle precursors, the time required for silane decomposition to produce particles, and the competing rate of growth of silicon seed particles injected into a decomposing silane environment were determined. The extent of silane decomposition as a function of residence time, temperature, and pressure was measured by infrared absorption spectroscopy. A simplistic model is presented to explain the growth of silicon in a decomposing silane enviroment.

  15. Dosimetric comparison of intensity modulated radiosurgery with dynamic conformal arc radiosurgery for small cranial lesions

    Directory of Open Access Journals (Sweden)

    Juan F Calvo-Ortega

    2016-01-01

    Conclusions: We have shown that IMRS provides the dosimetric advantages compared with DCARS. Based on the dosimetric findings in this study, fixed gantry IMRS technique can be adopted as a standard procedure for cranial SRS when micro-MLC technology is not available on the linear accelerator.

  16. THE DEVELOPMENT OF AN EXPERT SYSTEM IN THE AREA OF MATHMATICAL EDUCATION AT SCHOOL (8TH GRADE ON THE POLYLINGUALISM PLATFORM (RUSSIAN-TATAR-ENGLISH

    Directory of Open Access Journals (Sweden)

    Nurgaliev Albert Rustemovich

    2013-02-01

    Full Text Available With the increasing workload of a teacher arises a problem of fast diagnosing the deterioration of pupils’ academic performance with the corresponding differentiation of the academic workload. To cope with this problem an Expert System (ES has been developed, which is capable of consulting a teacher in questions related to the techniques of teaching a subject, from the analysis of pupils’ academic performance. The article uncovers the general didactic concepts of developing an ES in educational area on the example of teaching Algebra subject for the 8th grades based on polylingualism. During this research the architecture of the ES has been developed. In addition innovative approaches in analysis and processing of relevant data by the ES have been implemented in the form of a computer application. The model of analyzing pupils’ academic performance represented in grades is used as a basis for building an individual educational strategy. The system automatically selects the most optimal academic load for each individual pupil as well as for the entire class. This helps achieving flexibility during developing and realization of the study course. Due to the fact that some of the responsibilities of the teacher are taken by the ES, the teacher’s workload decreases, at the same time increasing the quality of education. The system is capable of analyzing current academic performance of each individual pupil in real time and depending on the improvement or deterioration in pupil performance it differentiates the load of a particular student for instance by generating individual homework exercises.

  17. Dosimetric confirmation of a software for the design of radiotherapy

    International Nuclear Information System (INIS)

    Alfonso, R.; Huerta, U.; Torres, M.; Alonso, J.L.

    1995-01-01

    A software for radiotherapy treatment has been recently designed by specialists in medical physics form Hermanos Ameijeiras Clinical and Surgical Hospital. Several locations in the distributions of dose calculations. The results of dosimetric measurements with TLD-700 powder in a human-like manikin were taken as reference. The different options available for the entry of patients shape data are explained. A comparison of the results of measurements with calculations, is presented. Causes of discrepancies are analyzed and recommendations regarding the usefulness of the different for the collection of data from patients are made

  18. Radioecological and dosimetric consequences of Chernobyl accident in France

    International Nuclear Information System (INIS)

    Renaud, Ph.; Beaugelin, K.; Maubert, H.; Ledenvic, Ph.

    1997-01-01

    After ten years and the taking in account of numerous data, it can be affirmed that the dosimetric consequences of Chernobyl accident will have been limited in France. for the period 1986-2046, the individual middle efficient dose commitment, for the area the most reached by depositing is inferior to 1500 μSv, that represents about 1% of middle natural exposure in the same time. but mountains and forests can have more important surface activities than in plain. Everywhere else, it can be considered that the effects of Chernobyl accident are disappearing. the levels of cesium 137 are now often inferior to what they were before the accident. (N.C.)

  19. Dosimetric evaluation of Radiotherapy units wit 60Co

    International Nuclear Information System (INIS)

    Leon, B. Salinas de; Tovar M, V.; Becerril V, A.

    2000-01-01

    The SSDL network of the IAEA performs, every year, quality audit tests for radiotherapy services ( 60 Co units and linear accelerators), and for national SSDL as well. Because of the SSDL-Mexico results in these tests and due to our enthusiasm and confidence in our work, a parallel test has been done , which is described in this talk as well as the results. Nowadays, a second parallel test goes up, which could confirm our optimism and open the possibility to our country to start a national dosimetric audit of 60 Co radiotherapy units. (Author)

  20. Dosimetric characteristics of a TLD dosemeter with extremities

    International Nuclear Information System (INIS)

    Molina P, D.; Diaz B, E.; Lien V, R.

    1999-01-01

    It was designed a TLD dosemeter for the monitoring of the extremities. This one consists in a metallic ring with a circular orifice where is arranged a T L detector of LiF: Mg,Ti (Model JR1152C) 5 x 5 x 0.8 mm 3 covered by a polyethylene fine layer. In this work were studied the dosimetric properties of the dosemeter for its application in the dosimetry of extremities for photonic radiation. the results obtained allow conclude that the designed dosemeter can be used for the extremities monitoring. (Author)

  1. The pitfalls of dosimetric commissioning for intensity modulated radiation therapy

    International Nuclear Information System (INIS)

    Tohyama, Naoki; Kodama, Takashi; Hatano, K.

    2013-01-01

    Intensity modulated radiation therapy (IMRT) allows higher radiation dose to be focused to the target volumes while minimizing the dose to OAR. To start of clinical treatment in IMRTvwe must perform commissioning strictly than 3D-conformal radiotherapy (CRT). In this report, pitfalls of dosimetric commissioning for intensity modulated radiation therapy were reviewed. Multileaf collimator (MLC) offsets and MLC transmissions are important parameters in commissioning of RTPS for IMRT. Correction of depth scaling and fluence scaling is necessary for dose measurement using solid phantom. (author)

  2. Pediatric phantoms for use in dosimetric calculations

    International Nuclear Information System (INIS)

    Shoup, R.L.; Hwang, J.L.; Poston, J.W.; Warner, G.G.

    1976-01-01

    Estimating absorbed doses to children from external and internal radiation sources has become important to the nuclear industry and pediatric nuclear medicine. The Medical Physics and Internal Dosimetry Section at ORNL has recently completed the design of mathematical representations of children of ages newborn, 1 year, and 5 years old. These mathematical representations will be referred to as pediatric phantoms. Using these phantoms, relevant energy deposition data have been developed which establish a meaningful model for use in estimating radiation dose to children

  3. First approval procedure of the TL dosimetric service of the NPP in Slovenia

    International Nuclear Information System (INIS)

    Janzekovic, H.; Krizman, M.; Pucelj, B.; Stuhec, M.; Zdesar, U.

    2001-01-01

    The individual dosimetry of exposed workers in a NPP is one of the essential parts which demonstrates the radiation protection standards achieved in a facility. According to the current legislation the Ministry of Health of the Republic of Slovenia has the authority to grant approvals to personal dosimetric services which perform the dosimetric monitoring of workers in Slovenia. Due to the fact that the detailed approval procedure is not given in national regulations, the Ministry of Health in 2000 established a group of experts with the task to prepare technical and organising requirements for such approval. Based on international documents [1,2,3] the Approval procedure for the thermoluminescence dosimetric (TL) services was created. Following this procedure the assessment of the TL dosimetric service in the NPP was performed. The problems related to the technical and organising requirements with the emphasise on the QA/QC criteria of the TL dosimetric service will be discussed.(author)

  4. Web system for dosimetric data management of internal monitoring programme at IPEN

    International Nuclear Information System (INIS)

    Lima, Vanesa R. de; Rodriguez Junior, Orlando; Todo, Alberto S.

    2008-01-01

    Full text: The internal monitoring programme are carried out for the occupationally exposed workers that develop activities in the radioisotope production plant, fuel cycle facilities, waste management installations, cyclotron and the reactor facility at Institute of Nuclear Energy and Research (IPEN). According to the National Nuclear Energy Commission (CNEN), Regulation NN-3.01, the dose of each worker should be maintained at least for a period of 30 years. With this purpose, an online system, called 'IntDosWeb', was developed with the objective of the management for data dosimetric of internal monitoring programme. The system IntDosWeb, based on free software, was developed in programming language PHP and environment database PostgreSQL. This system is to be available at the local net, Intranet. The database maintains information about identification of the worker that handles non-sealed radioactive sources, physical and chemical characteristics of the radionuclides, monitoring types, measurement data and the dose. This system is able to generate annual reports of the individuals and the historical dose. Several simulation cases have been put into effect to check the on-line software functional capabilities. The users can access the dosimetric information according to following database field: monitoring period, monitoring type, intake pattern, radionuclide type and monitoring data from a specific installation or from each worker. The system was tested in the routinely service of internal dosimetry at IPEN. The rastreability of the information made in the internal monitoring programme was a success and also guaranteeing the reliability and integrity of the stored information. The IntDosWeb was shown as a helpful tool for analysis of the committed effective dose in the radiation protection programme, besides obeying the legal demands of the Brazilian Regulatory Commission. (author)

  5. Dosimetric analysis of BNCT - Boron Neutron Capture Therapy - coupled to 252Cf brachytherapy

    International Nuclear Information System (INIS)

    Brandao, Samia F.; Campos, Tarcisio P.R.

    2009-01-01

    The incidence of brain tumors is increasing in world population; however, the treatments employed in this type of tumor have a high rate of failure and in some cases have been considered palliative, depending on histology and staging of tumor. Its necessary to achieve the control tumor dose without the spread irradiation cause damage in the brain, affecting patient neurological function. Stereotactic radiosurgery is a technique that achieves this; nevertheless, other techniques that can be used on the brain tumor control must be developed, in order to guarantee lower dose on health surroundings tissues other techniques must be developing. The 252 Cf brachytherapy applied to brain tumors has already been suggested, showing promising results in comparison to photon source, since the active source is placed into the tumor, providing greater dose deposition, while more distant regions are spared. BNCT - Boron Neutron Capture Therapy - is another technique that is in developing to brain tumors control, showing theoretical superiority on the rules of conventional treatments, due to a selective irradiation of neoplasics cells, after the patient receives a borate compound infusion and be subjected to a epithermal neutrons beam. This work presents dosimetric studies of the coupling techniques: BNCT with 252 Cf brachytherapy, conducted through computer simulation in MCNP5 code, using a precise and well discretized voxel model of human head, which was incorporated a representative Glioblastoma Multiform tumor. The dosimetric results from MCNP5 code were exported to SISCODES program, which generated isodose curves representing absorbed dose rate in the brain. Isodose curves, neutron fluency, and dose components from BNCT and 252 Cf brachytherapy are presented in this paper. (author)

  6. Dosimetric al confirmation of a software for the design of radiotherapy treatments

    International Nuclear Information System (INIS)

    Alfonso, Rodolfo; Huerta, Ubaldo; Torres, Miguel; Alonso, Jose L.

    1995-01-01

    A software for the planning of treatments of Radiotherapy was developed recently by medical physics of the Hospital Clinicoquirurgico Hermanos Ameijeiras, to evaluate the dependability of the results of the dose distributions calculated in the patients, localizations were chosen in the region of the head and the neck and I take like reference the results of measurement dosimetric with powder TLD-700 in a human phantoms. The different options are explained for the entrance of data of the patient's contours. A comparison of the results of the mensurations is shown with those calculated. The causes of the discrepancies are analyzed and recommendations are made regarding the utility of the different options of acquisition of the patient's data

  7. A reference dosimetric system for dose interval of radiotherapy based on alanine/RPE

    International Nuclear Information System (INIS)

    Rodrigues Junior, Orlando; Galante, Ocimar L.; Campos, Leticia L.

    2001-01-01

    This work describes the development of a reference dosimetric system based on alanine/EPR for radiotherapy dose levels. Currently the IPEN is concluding a similar system for the dose range used for irradiation of products, 10-10 5 Gy. The objective of this work is to present the efforts towards to improve the measure accuracy for doses in the range between 1-10 Gy. This system could be used as reference by radiotherapy services, as much in the quality control of the equipment, as for routine accompaniment of more complex handling where the total doses can reach some grays. The system uses alanine as detector and electronic paramagnetic resonance - EPR as measure technique. To reach accuracy better than 5% mathematical studies on the best optimization of the EPR spectrometer parameters and methods for the handling of the EPR sign are discussed. (author)

  8. Dosimetric studies, spectrometric, radiographic, metallographic of a new argentinean seed of 125 I used in brachytherapy

    International Nuclear Information System (INIS)

    Pirchio, R.; Saravi, M.; Banchik, D.; Munoz, C.

    2006-01-01

    A new source of 125 I model Braquibac TM has been developed in Argentina for applications in interstitial brachytherapy. The AAPM Task Group 43 (TG-43) recommends that dosimetric characteristics of new sources of brachytherapy of Iodine-125 have been theoretically and experimentally determined before its clinical use. The objectives outlined in this work were the study of the design of the new seed, the calculation of dosimetric parameters and the photons spectra analysis. Its were carried out radiographic and metallographic studies to determine the physical characteristics of the source. For the realization of the dosimetric calculations it was used the Monte Carlo code MCNP5. Values of the radial dose function, g(r), of the constant of dose rate, Λ, of the function of anisotropy of two dimensions, F(r, θ), of the factor and constant of anisotropy its were obtained simulating the source in water according to the recommended methodology in TG-43. The constant of dose rate is similar to 0,880 ± 0,080 c Gy h -1 U -1 . The kerma in air rate of reference, S K , was calculated as 1,036 c Gy cm 2 h -1 mCi -1 simulating the seed in dry air. Its were carried out spectrometric studies using a semiconductor planar detector of HPGe (high purity germanium). Photons spectra showed characteristic x-rays of 125 I with energies of 27,20 keV, 27,47 keV, 31 keV and 31,70 keV gamma photons of 35,5 keV, and x-ray fluorescent coming from the silver nucleus of 22,10 keV, 24,94 keV and 25,45 keV. The angular dependence of the intensity of photons around the seed and in air it was analyzed with the planar detector. This was carried out to study the anisotropy in the photons flow due to variation in the thickness of the titanium wall and of the welding, movements of the silver tube inside the source and deposition of the radioactive material on the silver tube. (Author)

  9. Clinical efficiency, image quality and dosimetric considerations

    International Nuclear Information System (INIS)

    Arreola, M.

    2000-01-01

    Three decades have passed since the first clinical use of the famous EMI Computed Axial Tomography (Cat) scanner. At the time, the prospects for clinical success of this innovative idea were not very good. Time, however, has proven otherwise as what is now simply known as Computed tomography (CT) has been boosted in each one of these decades for different reasons. In the 1970s, technological progress augmented by the realization of the importance of tomographic imaging got everything started; in the 1980s, the boom in health care demand in the US solidified its position and in the 1990s the technological explosion in computers and the imperative need to lower costs in the health care industry have prompted the most dramatic changes in the wy CT is utilized in the year 2000. Thus, different motivations have led the way of progress in CT at various times, and in spite of amazing developments in other crucial imaging modalities, such as ultrasound, Doppler ultrasound, digital subtraction angiography and magnetic resonance imaging, CT maintains its rightful place as the premiere imaging modality in the modern radiology department. This work covers the basic principles of tomographic image reconstruction, and how axial CT scanners progressed historically in the first two decades. Developments in X-ray tubes, and detection systems are highlighted, as well as the impact of clinical efficiency, image quality and patient doses. The basic construction of translate-rotate (1st and 2nd generation, rotate-rotate (3rd generation) and detector ring (4th generation) scanners are described. The so-called 5th generation scanner, the electron beam scanner, is also described, with its clinical and technical advantages and its inherent financial and maintenance disadvantages, which brought the advent of spiral and multi-slice scanners. These most recent developments in CT technology have opened a new era in the clinical use of CT; and although image quality has reached an expected

  10. Dosimetric evaluation of whole-breast radiation therapy: Clinical experience

    International Nuclear Information System (INIS)

    Osei, Ernest; Darko, Johnson; Fleck, Andre; White, Jana; Kiciak, Alexander; Redekop, Rachel; Gopaul, Darin

    2015-01-01

    Radiation therapy of the intact breast is the standard therapy for preventing local recurrence of early-stage breast cancer following breast conservation surgery. To improve patient standard of care, there is a need to define a consistent and transparent treatment path for all patients that reduces significance variations in the acceptability of treatment plans. There is lack of consistency among institutions or individuals about what is considered an acceptable treatment plan: target coverage vis-à-vis dose to organs at risk (OAR). Clinical trials usually resolve these issues, as the criteria for an acceptable plan within the trial (target coverage and doses to OAR) are well defined. We developed an institutional criterion for accepting breast treatment plans in 2006 after analyzing treatment data of approximately 200 patients. The purpose of this article is to report on the dosimetric review of 623 patients treated in the last 18 months to evaluate the effectiveness of the previously developed plan acceptability criteria and any possible changes necessary to further improve patient care. The mean patient age is 61.6 years (range: 25.2 to 93.0 years). The mean breast separation for all the patients is 21.0 cm (range: 12.4 to 34.9 cm), and the mean planning target volume (PTV_eval) (breast volume for evaluation) is 884.0 cm 3 (range: 73.6 to 3684.6 cm 3 ). Overall, 314 (50.4%) patients had the disease in the left breast and 309 (49.6%) had it in the right breast. A total of 147 (23.6%) patients were treated using the deep inspiration breath-hold (DIBH) technique. The mean normalized PTV_eval receiving at least 92% (V 92% PD ) and 95% (V 95% PD ) of the prescribed dose (PD) are more than 99% and 97%, respectively, for all patients. The mean normalized PTV_eval receiving at least 105% (V 105% PD ) of the PD is less than 1% for all groups. The mean homogeneity index (HI), uniformity index (UI), and conformity index (CI) for the PTV_eval are 0.09 (range: 0.05 to 0

  11. Developing a new PI-RADS v2-based nomogram for forecasting high-grade prostate cancer.

    Science.gov (United States)

    Niu, X-K; He, W-F; Zhang, Y; Das, S K; Li, J; Xiong, Y; Wang, Y-H

    2017-06-01

    To establish a predictive nomogram for high-grade prostate cancer (HGPCa) in biopsy-naive patients based on the Prostate Imaging-Reporting and Data System version 2 (PI-RADS v2), magnetic resonance imaging (MRI)-based prostate volume (PV), MRI-based PV-adjusted prostate-specific antigen density (PSAD), and other classical parameters. Between August 2014 and August 2015, 158 men who were eligible for analysis were included as the training cohort. A prediction model for HGPCa was built using backward logistic regression and was presented on a nomogram. The prediction model was evaluated by a validation cohort between September 2015 and March 2016 (n=89). Histology of all lesions was obtained with MRI-directed transrectal ultrasound (TRUS)-guided targeted and sectoral biopsy. The multivariate analysis revealed that patient age, PI-RADS v2 score, and adjusted PSAD were independent predictors for HGPCa. The most discriminative cut-off value for the logistic regression model was 0.33; the sensitivity, specificity, positive predictive value, and negative predictive value were 83.3%, 87.4%, 88.4%, and 81.2%, respectively. The diagnostic performance measures retained similar values in the validation cohort (AUC=0.83). The nomogram for forecasting HGPCa is effective and potentially reducing harm from unnecessary prostate biopsy and over-diagnosis. Copyright © 2016 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.

  12. Characterization and response of newly developed high-grade glioma cultures to the tyrosine kinase inhibitors, erlotinib, gefitinib and imatinib.

    LENUS (Irish Health Repository)

    Kinsella, Paula

    2012-03-10

    High-grade gliomas (HGG), are the most common aggressive brain tumours in adults. Inhibitors targeting growth factor signalling pathways in glioma have shown a low clinical response rate. To accurately evaluate response to targeted therapies further in vitro studies are necessary. Growth factor pathway expression using epidermal growth factor receptor (EGFR), mutant EGFR (EGFRvIII), platelet derived growth factor receptor (PDGFR), C-Kit and C-Abl together with phosphatase and tensin homolog (PTEN) expression and downstream activation of AKT and phosphorylated ribosomal protein S6 (P70S6K) was analysed in 26 primary glioma cultures treated with the tyrosine kinase inhibitors (TKIs) erlotinib, gefitinib and imatinib. Response to TKIs was assessed using 50% inhibitory concentrations (IC(50)). Response for each culture was compared with the EGFR\\/PDGFR immunocytochemical pathway profile using hierarchical cluster analysis (HCA) and principal component analysis (PCA). Erlotinib response was not strongly associated with high expression of the growth factor pathway components. PTEN expression did not correlate with response to any of the three TKIs. Increased EGFR expression was associated with gefitinib response; increased PDGFR-α expression was associated with imatinib response. The results of this in vitro study suggest gefitinib and imatinib may have therapeutic potential in HGG tumours with a corresponding growth factor receptor expression profile.

  13. Literacy for All? Using multilingual reading stories for literacy development in a Grade One classroom in the Western Cape

    Directory of Open Access Journals (Sweden)

    Prosper, Ancyfrida

    2016-12-01

    Full Text Available This paper reports on a literacy pilot project which investigated the use of multilingual reading books and the pedagogical strategies that were employed by one bilingual teacher and her assistant to teach literacy in a linguistically diverse Grade 1 classroom in a primary school in the Western Cape, South Africa. Data were collected by means of classroom observations and semi-structured interviews to understand the teacher’s literacy instruction, reflecting her understanding of the multilingual pedagogical approach as a means of fostering learners’ biliteracy skills. Through the lens of the social constructivist theory and the notion of biliteracy, this paper argues that bilingual competence does not necessarily translate to biliteracy if the teaching approaches and learning materials are not systematically and adequately used to support learners’ listening, oral, reading and writing skills in different languages in an integrated and holistic manner in multilingual classrooms. It concludes that, despite the progressive South African Language-in-Education Policy which supports additive multilingualism, classroom practices continue to reinforce monolingualism in English, which deprives the majority of learners of meaningful access to literacy in different languages as they do not exploit the socio-cultural and cognitive capital embedded in the learners’ home languages for additive bilingual and biliteracy competence.

  14. Comprehensive Australasian multicentre dosimetric intercomparison: issues, logistics and recommendations.

    Science.gov (United States)

    Ebert, M A; Harrison, K M; Cornes, D; Howlett, S J; Joseph, D J; Kron, T; Hamilton, C S; Denham, J W

    2009-02-01

    The present paper describes the logistics of the 2004-2008 Australasian Level III Dosimetry Intercomparison. Dosimetric intercomparisons (or 'audits') can be used in radiotherapy to evaluate the accuracy and quality of radiation delivery. An intercomparison was undertaken in New Zealand and Australia to evaluate the feasibility and logistics of ongoing dosimetric intercomparisons that evaluate all steps in the radiotherapy treatment process, known as a 'Level III' intercomparison. The study commenced in 2002 with the establishment of a study team, definition of the study protocol, acquisition of appropriate equipment and recruitment of participating radiotherapy centres. Measurements were undertaken between October 2004 and March 2008, and included collation of data on time, costs and logistics of the study. Forty independent Australian and New Zealand radiotherapy centres agreed to participate. Measurement visits were made to 37 of these centres. Data is presented on the costs of the study and the level of support required. The study involved the participation of 16 staff at the study centre who invested over 4000 hours in the study, and of over 200 professionals at participating centres. Recommendations are provided for future phantom-based intercomparisons. It is hoped that the present paper will be of benefit to any centres or groups contemplating similar activities by identifying the processes involved in establishing the study, the potential hazards and pitfalls, and expected resource requirements.

  15. Dosimetric Algorithm to Reproduce Isodose Curves Obtained from a LINAC

    Directory of Open Access Journals (Sweden)

    Julio Cesar Estrada Espinosa

    2014-01-01

    Full Text Available In this work isodose curves are obtained by the use of a new dosimetric algorithm using numerical data from percentage depth dose (PDD and the maximum absorbed dose profile, calculated by Monte Carlo in a 18 MV LINAC. The software allows reproducing the absorbed dose percentage in the whole irradiated volume quickly and with a good approximation. To validate results an 18 MV LINAC with a whole geometry and a water phantom were constructed. On this construction, the distinct simulations were processed by the MCNPX code and then obtained the PDD and profiles for the whole depths of the radiation beam. The results data were used by the code to produce the dose percentages in any point of the irradiated volume. The absorbed dose for any voxel’s size was also reproduced at any point of the irradiated volume, even when the voxels are considered to be of a pixel’s size. The dosimetric algorithm is able to reproduce the absorbed dose induced by a radiation beam over a water phantom, considering PDD and profiles, whose maximum percent value is in the build-up region. Calculation time for the algorithm is only a few seconds, compared with the days taken when it is carried out by Monte Carlo.

  16. The process of collecting and evaluating evidences for the development of Guidelines for the management of rheumatoid arthritis, Japan College of Rheumatology 2014: Utilization of GRADE approach.

    Science.gov (United States)

    Kojima, Masayo; Nakayama, Takeo; Kawahito, Yutaka; Kaneko, Yuko; Kishimoto, Mitsumasa; Hirata, Shintaro; Seto, Yohei; Endo, Hirahito; Ito, Hiromu; Kojima, Toshihisa; Nishida, Keiichiro; Matsushita, Isao; Tsutani, Kiichiro; Igarashi, Ataru; Kamatani, Naoyuki; Hasegawa, Mieko; Miyasaka, Nobuyuki; Yamanaka, Hisashi

    2016-01-01

    To describe the process of collecting and evaluating evidence for treating rheumatoid arthritis (RA) for developing clinical practice guidelines (CPGs) for rheumatologists in Japan. The task force comprised rheumatologists, epidemiologists, health economists, and patients. First, the critical outcomes were determined according to a three-round Delphi method, and eight topics with 88 clinical questions (CQs) were formulated. A systematic review of CQs was conducted using the Cochran Database of Systematic Reviews, MEDLINE, and Japana Centra Revvo Medicina (2003-2012). A questionnaire survey and focus group interview were performed to capture the patients' values and preferences. Data from the National Health Insurance drug price list and product information provided by pharmaceutical companies were collected to evaluate drug cost and safety. The GRADE approach was used to describe the evidence quality and determine the strength of recommendations. Recommendations were developed using a modified Delphi method by a multidisciplinary panel including patients. Eight meetings and frequent e-mail communications were conducted to draft a quality assessment of evidence and recommendations. For 88 CQs, recommendation statements were determined. Using the GRADE approach, new CPGs successfully addressed important clinical issues for treating RA patients. Timely updating of recommendations should be routinely considered.

  17. Development and External Validation of the Korean Prostate Cancer Risk Calculator for High-Grade Prostate Cancer: Comparison with Two Western Risk Calculators in an Asian Cohort.

    Science.gov (United States)

    Park, Jae Young; Yoon, Sungroh; Park, Man Sik; Choi, Hoon; Bae, Jae Hyun; Moon, Du Geon; Hong, Sung Kyu; Lee, Sang Eun; Park, Chanwang; Byun, Seok-Soo

    2017-01-01

    We developed the Korean Prostate Cancer Risk Calculator for High-Grade Prostate Cancer (KPCRC-HG) that predicts the probability of prostate cancer (PC) of Gleason score 7 or higher at the initial prostate biopsy in a Korean cohort (http://acl.snu.ac.kr/PCRC/RISC/). In addition, KPCRC-HG was validated and compared with internet-based Western risk calculators in a validation cohort. Using a logistic regression model, KPCRC-HG was developed based on the data from 602 previously unscreened Korean men who underwent initial prostate biopsies. Using 2,313 cases in a validation cohort, KPCRC-HG was compared with the European Randomized Study of Screening for PC Risk Calculator for high-grade cancer (ERSPCRC-HG) and the Prostate Cancer Prevention Trial Risk Calculator 2.0 for high-grade cancer (PCPTRC-HG). The predictive accuracy was assessed using the area under the receiver operating characteristic curve (AUC) and calibration plots. PC was detected in 172 (28.6%) men, 120 (19.9%) of whom had PC of Gleason score 7 or higher. Independent predictors included prostate-specific antigen levels, digital rectal examination findings, transrectal ultrasound findings, and prostate volume. The AUC of the KPCRC-HG (0.84) was higher than that of the PCPTRC-HG (0.79, p<0.001) but not different from that of the ERSPCRC-HG (0.83) on external validation. Calibration plots also revealed better performance of KPCRC-HG and ERSPCRC-HG than that of PCPTRC-HG on external validation. At a cut-off of 5% for KPCRC-HG, 253 of the 2,313 men (11%) would not have been biopsied, and 14 of the 614 PC cases with Gleason score 7 or higher (2%) would not have been diagnosed. KPCRC-HG is the first web-based high-grade prostate cancer prediction model in Korea. It had higher predictive accuracy than PCPTRC-HG in a Korean population and showed similar performance with ERSPCRC-HG in a Korean population. This prediction model could help avoid unnecessary biopsy and reduce overdiagnosis and overtreatment in

  18. Development and External Validation of the Korean Prostate Cancer Risk Calculator for High-Grade Prostate Cancer: Comparison with Two Western Risk Calculators in an Asian Cohort.

    Directory of Open Access Journals (Sweden)

    Jae Young Park

    Full Text Available We developed the Korean Prostate Cancer Risk Calculator for High-Grade Prostate Cancer (KPCRC-HG that predicts the probability of prostate cancer (PC of Gleason score 7 or higher at the initial prostate biopsy in a Korean cohort (http://acl.snu.ac.kr/PCRC/RISC/. In addition, KPCRC-HG was validated and compared with internet-based Western risk calculators in a validation cohort.Using a logistic regression model, KPCRC-HG was developed based on the data from 602 previously unscreened Korean men who underwent initial prostate biopsies. Using 2,313 cases in a validation cohort, KPCRC-HG was compared with the European Randomized Study of Screening for PC Risk Calculator for high-grade cancer (ERSPCRC-HG and the Prostate Cancer Prevention Trial Risk Calculator 2.0 for high-grade cancer (PCPTRC-HG. The predictive accuracy was assessed using the area under the receiver operating characteristic curve (AUC and calibration plots.PC was detected in 172 (28.6% men, 120 (19.9% of whom had PC of Gleason score 7 or higher. Independent predictors included prostate-specific antigen levels, digital rectal examination findings, transrectal ultrasound findings, and prostate volume. The AUC of the KPCRC-HG (0.84 was higher than that of the PCPTRC-HG (0.79, p<0.001 but not different from that of the ERSPCRC-HG (0.83 on external validation. Calibration plots also revealed better performance of KPCRC-HG and ERSPCRC-HG than that of PCPTRC-HG on external validation. At a cut-off of 5% for KPCRC-HG, 253 of the 2,313 men (11% would not have been biopsied, and 14 of the 614 PC cases with Gleason score 7 or higher (2% would not have been diagnosed.KPCRC-HG is the first web-based high-grade prostate cancer prediction model in Korea. It had higher predictive accuracy than PCPTRC-HG in a Korean population and showed similar performance with ERSPCRC-HG in a Korean population. This prediction model could help avoid unnecessary biopsy and reduce overdiagnosis and overtreatment in

  19. Dosimetric and Clinical Outcomes With Intensity Modulated Radiation Therapy After Chemotherapy for Patients With Early-Stage Diffuse Large B-cell Lymphoma of Waldeyer Ring

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Yong-Gang; Qi, Shu-Nan; Wang, Shu-Lian; Liu, Yue-Ping; Wang, Wei-Hu; Jin, Jing; Song, Yong-Wen; Ren, Hua; Fang, Hui [Department of Radiation Oncology, Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing (China); He, Xiao-Hui; Dong, Mei [Department of Medical Oncology, Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing (China); Chen, Bo; Lu, Ning-Ning; Li, Ning; Tang, Yuan; Tang, Yu; Dai, Jian-Rong [Department of Radiation Oncology, Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing (China); Li, Ye-Xiong, E-mail: yexiong12@163.com [Department of Radiation Oncology, Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing (China)

    2016-10-01

    Purpose: To assess the dosimetric benefit, prognosis, and toxicity of intensity modulated radiation therapy (IMRT) for early-stage, diffuse large B-cell lymphoma of Waldeyer ring (WR-DLBCL). Methods and Materials: Sixty-one patients with early-stage WR-DLBCL who received chemotherapy followed by IMRT were retrospectively reviewed. Dosimetric parameters for the target volume and critical normal structures were evaluated, and survival was calculated. Linear regression analysis was used to assess the effect of the mean dose (D{sub mean}) to the parotid glands on xerostomia. Results: The median conformity index and homogeneity index of the planning target volume (PTV) were 0.83 and 0.90, respectively, demonstrating very good coverage of the target volume. The mean dose to the parotid glands was 24.9 Gy. The 5-year overall survival (OS), progression-free survival (PFS), and locoregional control (LRC) were 94.7%, 93.1%, and 98.3%, respectively. Early and late toxicities were mild, and no patient experienced late grade ≥3 toxicities. The D{sub mean} to the parotid glands had a linear correlation with late grade ≥2 xerostomia. Conclusions: IMRT after chemotherapy can provide excellent dose conformity and achieve favorable survival and LRC with mild toxicities in patients with early-stage WR-DLBCL. Dose constraints for the parotid glands should be limited to <24 Gy for early-stage WR-DLBCL.

  20. EPA GHG Certification of Medium- and Heavy-Duty Vehicles: Development of Road Grade Profiles Representative of US Controlled Access Highways

    Energy Technology Data Exchange (ETDEWEB)

    Wood, Eric [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Duran, Adam [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Burton, Evan [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Gonder, Jeffrey [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Kelly, Kenneth [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

    2015-05-12

    This report includes a detailed comparison of the TomTom national road grade database relative to a local road grade dataset generated by Southwest Research Institute and a national elevation dataset publically available from the U.S. Geological Survey. This analysis concluded that the TomTom national road grade database was a suitable source of road grade data for purposes of this study.

  1. Characterization and response of newly developed high-grade glioma cultures to the tyrosine kinase inhibitors, erlotinib, gefitinib and imatinib

    International Nuclear Information System (INIS)

    Kinsella, Paula; Howley, Rachel; Doolan, Padraig; Clarke, Colin; Madden, Stephen F.; Clynes, Martin; Farrell, Michael; Amberger-Murphy, Verena

    2012-01-01

    High-grade gliomas (HGG), are the most common aggressive brain tumours in adults. Inhibitors targeting growth factor signalling pathways in glioma have shown a low clinical response rate. To accurately evaluate response to targeted therapies further in vitro studies are necessary. Growth factor pathway expression using epidermal growth factor receptor (EGFR), mutant EGFR (EGFRvIII), platelet derived growth factor receptor (PDGFR), C-Kit and C-Abl together with phosphatase and tensin homolog (PTEN) expression and downstream activation of AKT and phosphorylated ribosomal protein S6 (P70S6K) was analysed in 26 primary glioma cultures treated with the tyrosine kinase inhibitors (TKIs) erlotinib, gefitinib and imatinib. Response to TKIs was assessed using 50% inhibitory concentrations (IC 50 ). Response for each culture was compared with the EGFR/PDGFR immunocytochemical pathway profile using hierarchical cluster analysis (HCA) and principal component analysis (PCA). Erlotinib response was not strongly associated with high expression of the growth factor pathway components. PTEN expression did not correlate with response to any of the three TKIs. Increased EGFR expression was associated with gefitinib response; increased PDGFR-α expression was associated with imatinib response. The results of this in vitro study suggest gefitinib and imatinib may have therapeutic potential in HGG tumours with a corresponding growth factor receptor expression profile. -- Highlights: ► Non-responders had low EGFR expression, high PDGFR-β, and a low proliferation rate. ► PTEN is not indicative of response to a TKI. ► Erlotinib response was not associated with expression of the proteins examined. ► Imatinib-response correlated with expression of PDGFR-α. ► Gefitinib response correlated with increased expression of EGFR.

  2. Characterization and response of newly developed high-grade glioma cultures to the tyrosine kinase inhibitors, erlotinib, gefitinib and imatinib

    Energy Technology Data Exchange (ETDEWEB)

    Kinsella, Paula, E-mail: paula.kinsella@dcu.ie [National Institute for Cellular Biotechnology, Dublin City University, Dublin 9 (Ireland); Howley, Rachel, E-mail: rhowley@rcsi.ie [Department of Neuropathology, Beaumont Hospital, Dublin 9 (Ireland); Doolan, Padraig, E-mail: padraig.doolan@dcu.ie [National Institute for Cellular Biotechnology, Dublin City University, Dublin 9 (Ireland); Clarke, Colin, E-mail: colin.clarke@dcu.ie [National Institute for Cellular Biotechnology, Dublin City University, Dublin 9 (Ireland); Madden, Stephen F., E-mail: maddens@dcu.ie [National Institute for Cellular Biotechnology, Dublin City University, Dublin 9 (Ireland); Clynes, Martin, E-mail: Martin.Clynes@dcu.ie [National Institute for Cellular Biotechnology, Dublin City University, Dublin 9 (Ireland); Farrell, Michael, E-mail: michaelfarrell@beaumont.ie [Department of Neuropathology, Beaumont Hospital, Dublin 9 (Ireland); Amberger-Murphy, Verena, E-mail: Verena.Murphy@icorg.ie [National Institute for Cellular Biotechnology, Dublin City University, Dublin 9 (Ireland); All Ireland Co-operative, Oncology Research Group, 60 Fitzwilliam Square, Dublin 2 (Ireland)

    2012-03-10

    High-grade gliomas (HGG), are the most common aggressive brain tumours in adults. Inhibitors targeting growth factor signalling pathways in glioma have shown a low clinical response rate. To accurately evaluate response to targeted therapies further in vitro studies are necessary. Growth factor pathway expression using epidermal growth factor receptor (EGFR), mutant EGFR (EGFRvIII), platelet derived growth factor receptor (PDGFR), C-Kit and C-Abl together with phosphatase and tensin homolog (PTEN) expression and downstream activation of AKT and phosphorylated ribosomal protein S6 (P70S6K) was analysed in 26 primary glioma cultures treated with the tyrosine kinase inhibitors (TKIs) erlotinib, gefitinib and imatinib. Response to TKIs was assessed using 50% inhibitory concentrations (IC{sub 50}). Response for each culture was compared with the EGFR/PDGFR immunocytochemical pathway profile using hierarchical cluster analysis (HCA) and principal component analysis (PCA). Erlotinib response was not strongly associated with high expression of the growth factor pathway components. PTEN expression did not correlate with response to any of the three TKIs. Increased EGFR expression was associated with gefitinib response; increased PDGFR-{alpha} expression was associated with imatinib response. The results of this in vitro study suggest gefitinib and imatinib may have therapeutic potential in HGG tumours with a corresponding growth factor receptor expression profile. -- Highlights: Black-Right-Pointing-Pointer Non-responders had low EGFR expression, high PDGFR-{beta}, and a low proliferation rate. Black-Right-Pointing-Pointer PTEN is not indicative of response to a TKI. Black-Right-Pointing-Pointer Erlotinib response was not associated with expression of the proteins examined. Black-Right-Pointing-Pointer Imatinib-response correlated with expression of PDGFR-{alpha}. Black-Right-Pointing-Pointer Gefitinib response correlated with increased expression of EGFR.

  3. Quality assurance procedures based on dosimetric, gamma analysis as a fast reliable tool for commissioning brachytherapy treatment planning systems

    Directory of Open Access Journals (Sweden)

    Zwierzchowski Grzegorz

    2017-11-01

    Full Text Available Fast and easily repeatable methods for commissioning procedures for brachytherapy (BT treatment planning systems (TPS are needed. Radiochromic film dosimetry with gamma analysis is widely used in external beam quality assurance (QA procedures and planar film dosimetry is also increasingly used for verification of the dose distribution in BT applications. Using the gamma analysis method for comparing calculated and measured dose data could be used for commissioning procedures of the newly developed TG-186 and MBDCA calculation algorithms. The aim of this study was dosimetric verification of the calculation algorithm used in TPS when the CT/MRI ring applicator is used.

  4. Correlation of Clinical and Dosimetric Factors With Adverse Pulmonary Outcomes in Children After Lung Irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Venkatramani, Rajkumar, E-mail: rvenkatramani@chla.usc.edu [Division of Hematology/Oncology, Children' s Hospital Los Angeles, Los Angeles, California (United States); Department of Pediatrics, Keck School of Medicine, University of Southern California, Los Angeles, California (United States); Kamath, Sunil [Department of Pulmonology, Children' s Hospital Los Angeles, Los Angeles, California (United States); Wong, Kenneth [Division of Hematology/Oncology, Children' s Hospital Los Angeles, Los Angeles, California (United States); Olch, Arthur J. [Division of Hematology/Oncology, Children' s Hospital Los Angeles, Los Angeles, California (United States); Department of Radiation Oncology, University of Southern California, Los Angeles, California (United States); Malvar, Jemily [Department of Preventive Medicine, Keck School of Medicine, University of Southern California, Los Angeles, California (United States); Sposto, Richard [Division of Hematology/Oncology, Children' s Hospital Los Angeles, Los Angeles, California (United States); Department of Preventive Medicine, Keck School of Medicine, University of Southern California, Los Angeles, California (United States); Goodarzian, Fariba [Department of Radiology, Children' s Hospital Los Angeles, Los Angeles, California (United States); Freyer, David R. [Division of Hematology/Oncology, Children' s Hospital Los Angeles, Los Angeles, California (United States); Department of Pediatrics, Keck School of Medicine, University of Southern California, Los Angeles, California (United States); Keens, Thomas G. [Department of Pediatrics, Keck School of Medicine, University of Southern California, Los Angeles, California (United States); Department of Pulmonology, Children' s Hospital Los Angeles, Los Angeles, California (United States); and others

    2013-08-01

    Purpose: To identify the incidence and the risk factors for pulmonary toxicity in children treated for cancer with contemporary lung irradiation. Methods and Materials: We analyzed clinical features, radiographic findings, pulmonary function tests, and dosimetric parameters of children receiving irradiation to the lung fields over a 10-year period. Results: We identified 109 patients (75 male patients). The median age at irradiation was 13.8 years (range, 0.04-20.9 years). The median follow-up period was 3.4 years. The median prescribed radiation dose was 21 Gy (range, 0.4-64.8 Gy). Pulmonary toxic chemotherapy included bleomycin in 58.7% of patients and cyclophosphamide in 83.5%. The following pulmonary outcomes were identified and the 5-year cumulative incidence after irradiation was determined: pneumonitis, 6%; chronic cough, 10%; pneumonia, 35%; dyspnea, 11%; supplemental oxygen requirement, 2%; radiographic interstitial lung disease, 40%; and chest wall deformity, 12%. One patient died of progressive respiratory failure. Post-irradiation pulmonary function tests available from 44 patients showed evidence of obstructive lung disease (25%), restrictive disease (11%), hyperinflation (32%), and abnormal diffusion capacity (12%). Thoracic surgery, bleomycin, age, mean lung irradiation dose (MLD), maximum lung dose, prescribed dose, and dosimetric parameters between V{sub 22} (volume of lung exposed to a radiation dose ≥22 Gy) and V{sub 30} (volume of lung exposed to a radiation dose ≥30 Gy) were significant for the development of adverse pulmonary outcomes on univariate analysis. MLD, maximum lung dose, and V{sub dose} (percentage of volume of lung receiving the threshold dose or greater) were highly correlated. On multivariate analysis, MLD was the sole significant predictor of adverse pulmonary outcome (P=.01). Conclusions: Significant pulmonary dysfunction occurs in children receiving lung irradiation by contemporary techniques. MLD rather than prescribed

  5. Student Attitudes Toward Grades and Grading Practices.

    Science.gov (United States)

    Stallings, William M.; Leslie, Elwood K.

    The result of a study designed to assess student attitudes toward grading practices are discussed. Questionnaire responses of 3439 students in three institutions were tabulated. Responses were generally negative toward conventional grading systems. (MS)

  6. Development of the Method of Bacterial Leaching of Metals out of Low-Grade Ores, Rocks, and Industrial Wastes Using Neutron Activation Analysis

    CERN Document Server

    Tsertsvadze, L A; Petriashvili, Sh G; Chutkerashvili, D G; Kirkesali, E I; Frontasyeva, M V; Pavlov, S S; Gundorina, S F

    2001-01-01

    The results of preliminary investigations aimed at the development of an economical and easy to apply technique of bacterial leaching of rare and valuable metals out of low-grade ores, complex composition ores, rocks, and industrial wastes in Georgia are discussed. The main groups of microbiological community of the peat suspension used in the experiments of bacterial leaching are investigated and the activity of particular microorganisms in the leaching of probes with different mineral compositions is assessed. The element composition of the primary and processed samples was investigated by the epithermal neutron activation analysis method and the enrichment/subtraction level is estimated for various elements. The efficiency of the developed technique to purify wastes, extract some scrace metals, and enrich ores or rocks in some elements, e.g. Au, U, Th, Cs, Sr, Rb, Sc, Zr, Hf, Ta, Gd, Er, Lu, Ce, etc., is demonstrated.

  7. Development of graded Ni-YSZ composite coating on Alloy 690 by Pulsed Laser Deposition technique to reduce hazardous metallic nuclear waste inventory.

    Science.gov (United States)

    Sengupta, Pranesh; Rogalla, Detlef; Becker, Hans Werner; Dey, Gautam Kumar; Chakraborty, Sumit

    2011-08-15

    Alloy 690 based 'nuclear waste vitrification furnace' components degrade prematurely due to molten glass-alloy interactions at high temperatures and thereby increase the volume of metallic nuclear waste. In order to reduce the waste inventory, compositionally graded Ni-YSZ (Y(2)O(3) stabilized ZrO(2)) composite coating has been developed on Alloy 690 using Pulsed Laser Deposition technique. Five different thin-films starting with Ni80YSZ20 (Ni 80 wt%+YSZ 20 wt%), through Ni60YSZ40 (Ni 60 wt%+YSZ 40 wt%), Ni40YSZ60 (Ni 40 wt%+YSZ 60 wt%), Ni20YSZ80 (Ni 20 wt%+YSZ 80 wt%) and Ni0YSZ100 (Ni 0 wt%+YSZ 100 wt%), were deposited successively on Alloy 690 coupons. Detailed analyses of the thin-films identify them as homogeneous, uniform, pore free and crystalline in nature. A comparative study of coated and uncoated Alloy 690 coupons, exposed to sodium borosilicate melt at 1000°C for 1-6h suggests that the graded composite coating could substantially reduced the chemical interactions between Alloy 690 and borosilicate melt. Copyright © 2011 Elsevier B.V. All rights reserved.

  8. The Early Morphological Development of the Near Surface Region of Pickled Grade 91 Tubing Exposed to Steam and Its Long Term Implications

    Directory of Open Access Journals (Sweden)

    David M. Gorman

    2016-03-01

    Full Text Available To improve intra-laboratory consistency and experimental repeatability during high temperature oxidation testing, metallic coupons undergo a standardised surface preparation. It is stipulated in international testing standards that grinding of a coupons surface acceptably replicates surface conditions encountered in industrial settings whilst ensuring that each coupons surface is chemically and topographically homogenised [1,2]. Grade 91 steel tubing exposed in the laboratory to flowing steam at 650 °C and 1 bar for up to 3000 h has been compared with Grade 91 tubing exposed in a commercially operated boiler system at elevated pressures at temperatures in the range of 500 to 650 °C for 91 kh. It has been found that a pre-existing surface structure dissimilar from that of the bulk alloy and that of a ground surface, is present on the inside surface of the tubing. The presence of pre-existing surface features in commercially exposed material has implications on the long term morphological development of the oxidation region and may account for some of the discrepancies between observations made in laboratory and service exposures.

  9. Association of Aneuploidy and Flat Dysplasia With Development of High-Grade Dysplasia or Colorectal Cancer in Patients With Inflammatory Bowel Disease.

    Science.gov (United States)

    Tsai, Jia-Huei; Rabinovitch, Peter S; Huang, Danning; Small, Thomas; Mattis, Aras N; Kakar, Sanjay; Choi, Won-Tak

    2017-12-01

    There is controversy over how to best manage patients with inflammatory bowel disease and flat low-grade dysplasia (fLGD) in the colon. We performed a retrospective analysis of formalin-fixed paraffin-embedded colon tissues with fLGD from 37 patients undergoing surveillance colonoscopy for inflammatory bowel disease from 1990 to 2015 at the University of California at San Francisco Medical Center, to determine whether detection of aneuploidy is associated with later development of high-grade dysplasia (HGD) or colorectal cancer. Medical data were collected from the patients for a mean follow-up time of 37 months. Using flow cytometry analysis of paraffin-embedded colon tissue, we detected aneuploidy in 15 of 37 samples with fLGD (40.5%). By comparison, aneuploidy was detected in 14 of 15 samples with flat HGD (93.3%) and 2 of 45 samples that were negative for dysplasia (4.4%). The univariate hazard ratio for subsequent detection of HGD or colorectal cancer in patients with fLGD and aneuploidy was 5.3 (95% CI, 1.542-24.121) within a mean follow-up time of 37 months. The presence of aneuploidy therefore identifies patients with fLGD in colon tissue who have an increased risk for HGD or colorectal cancer and may provide supportive evidence to a morphologic impression or suspicion of flat HGD. Copyright © 2017 AGA Institute. Published by Elsevier Inc. All rights reserved.

  10. Development and Evaluation of a Career Continuance Model for Company Grade Officers in the United States Army

    Science.gov (United States)

    2011-03-01

    job embeddedness increases with time in the same place as the number of links increases and investments accumulate. As a result, commitment and its...Conditions on Theoretical Relationships ............10 Need to Incorporate Job Embeddedness ...officers who have developed or can develop the qualities needed for high job performance and organizational effectiveness, and who choose to stay with the

  11. The Development of Adolescents' Self-Concept of Ability through Grades 7-9 and the Role of Parental Beliefs

    Science.gov (United States)

    Pesu, Laura; Aunola, Kaisa; Viljaranta, Jaana; Nurmi, Jari-Erik

    2016-01-01

    This study examined the development of adolescents' self-concept of ability in mathematics and literacy during secondary school, and the role that mothers' and fathers' beliefs concerning their child's abilities play in this development. Also examined was whether the role of mothers' and fathers' beliefs about their adolescent child's ability in…

  12. Intellectual Development Is Positively Related to Intrinsic Motivation and Course Grades for Female but Not Male Students

    Science.gov (United States)

    Cortright, Ronald N.; Lujan, Heidi L.; Cox, Julie H.; Cortright, Maria A.; Langworthy, Brandon M.; Petta, Lorene M.; Tanner, Charles J.; DiCarlo, Stephen E.

    2015-01-01

    We hypothesized that the intellectual development of students, i.e., their beliefs about the nature of knowledge and learning, affects their intrinsic motivation and class performance. Specifically, we hypothesized that students with low intellectual development (i.e., the naive beliefs that knowledge is simple, absolute, and certain) have low…

  13. Production of LiF films for dosimetric thermoluminescence application

    International Nuclear Information System (INIS)

    Mauricio, Claudia Lucia de Pinho

    2000-12-01

    This work studies the LiF monolayer and multilayer polycrystalline film's dosimetric properties. The films were produced by electron beam evaporation technique in aluminium and stainless steel substrates maintained at several temperatures. As dosimetric variable, the intensity of the thermoluminescent (TL) glow curve of the films was used. effects of the substrate type and temperature; of the addition of layers of Mg F 2 NaF and Cu F 2 to the LiF films; and of thermal treatments in the TL response of the produced films were studied. The microstructural characterization of the films was accomplished through measures of scanning electronic microscopy and grazing incidence X-rays diffraction analysis. The dosimetric characterization was made of gamma radiation exposure in a 60 Co source, with kerma from 0,1 to 500 Gy. Studies of reproducibility, homogeneity, stability and other environmental effects were also made. LiF and Cu F 2 : LiF; Mg F 2 films were the only ones that presented mechanical stability and reproducibility of the TL emission. There is a strong indication of some correlation between the residual tension fields inside the films and the intensity of its TL emission peaks. LiF monolayer films present supralinear behaviour from 0,2 to 100 Gy. These films present a main TL glow peak around 150 deg C, whose half-time is about 30 days. Its volumetric sensitivity can reach about 60 times that of LiF powder and about 0,25 that of TLD100 (LiF:Mg, Ti commercial dosimeter from Harshaw Chemical Co.) The homogeneity and reproducibility inside a same film batch is better than 12% for 95% confidence level. Cu F 2 : LiF: Mg F 2 films present linear behaviour from 3 to 500 Gy and its main TL glow peak around 200 deg C did not present any fading for a a period of 30 days, in laboratory conditions. This glow peak is characteristic of the Mg doping of LiF, which confirms the diffusion of Mg ions from the Mg F 2 layer to the LiF layer. The TL volumetric sensitivity of these

  14. Intellectual development is positively related to intrinsic motivation and course grades for female but not male students.

    Science.gov (United States)

    Cortright, Ronald N; Lujan, Heidi L; Cox, Julie H; Cortright, Maria A; Langworthy, Brandon M; Petta, Lorene M; Tanner, Charles J; DiCarlo, Stephen E

    2015-09-01

    We hypothesized that the intellectual development of students, i.e., their beliefs about the nature of knowledge and learning, affects their intrinsic motivation and class performance. Specifically, we hypothesized that students with low intellectual development (i.e., the naive beliefs that knowledge is simple, absolute, and certain) have low intrinsic motivation and low class performance, whereas students with high intellectual development (i.e., more sophisticated beliefs that knowledge is complex, tentative, and evolving) have high intrinsic motivation and class performance. To test this hypothesis, we administered the Learning Context Questionnaire to measure intellectual development. In addition, we administered the Intrinsic Motivation Inventory to assess our students' intrinsic motivation. Furthermore, we performed regression analyses between intellectual development with both intrinsic motivation and class performance. The results document a positive relationship among intellectual development, intrinsic motivation, and class performance for female students only. In sharp contrast, there was a negative relationship between intellectual development, intrinsic motivation, and class performance for male students. The slope comparisons documented significant differences in the slopes relating intellectual development, intrinsic motivation, and class performance between female and male students. Thus, female students with more sophisticated beliefs that knowledge is personally constructed, complex, and evolving had higher intrinsic motivation and class performance. In contrast, male students with the naive beliefs that the structure of knowledge is simple, absolute, and certain had higher levels of intrinsic motivation and class performance. The results suggest that sex influences intellectual development, which has an effect on intrinsic motivation for learning a specific topic. Copyright © 2015 The American Physiological Society.

  15. The role of Cochrane reviews in informing international guidelines: a case study of using the Grading of Recommendations, Assessment, Development and Evaluation system to develop World Health Organization guidelines for the psychosocially assisted pharmacological treatment of opioid dependence.

    Science.gov (United States)

    Davoli, Marina; Amato, Laura; Clark, Nicolas; Farrell, Michael; Hickman, Matthew; Hill, Suzanne; Magrini, Nicola; Poznyak, Vladimir; Schünemann, Holger J

    2015-06-01

    The World Health Organization (WHO), and a growing number of other organizations, have adopted the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) system in order to both assess the quality of research evidence and develop clinical practice guidelines. In 2009 WHO published a guideline on psychosocially assisted pharmacological treatment of opioid dependence, based on the results of Cochrane Reviews summarized using the GRADE methodology. The main features of this system are an a priori definition of outcomes and their relevance, and distinction between the quality of evidence (also referred to as confidence in the estimate of intervention effect) and the strength of recommendations. We consider how successful this approach has been. We discuss the merits and limitations of using Cochrane Reviews and GRADE framework in developing guidelines in the field of drug addiction. In 2009 a panel of multi-disciplinary international experts identified 15 clinical questions and eight relevant outcomes. Cochrane reviews were available for each clinical question and four outcomes. The panel formulated 15 recommendations. Eight recommendations were classified as strong, two of which were based on high-quality evidence and three on very low-quality evidence. For example, the strong recommendation to use methadone in adequate doses in preference to buprenorphine was based on high-quality evidence, while the strong recommendation not to use the combination of opioid antagonists with heavy sedation in the management of opioid withdrawal was based on low-quality evidence. An explicit stepwise process of moving from evaluation of the quality of evidence to the definition of the strength of recommendations is important in providing practical and clear clinical guidance for practitioners and policy-makers in addiction. © 2014 Society for the Study of Addiction.

  16. Dosimetric Predictors of Duodenal Toxicity After Intensity Modulated Radiation Therapy for Treatment of the Para-aortic Nodes in Gynecologic Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Verma, Jonathan [Department of Radiation Oncology, University of Miami Miller School of Medicine, Miami, Florida (United States); Sulman, Erik P.; Jhingran, Anuja [Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Tucker, Susan L. [Department of Bioinformatics and Computational Biology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Rauch, Gaiane M. [Department of Radiology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Eifel, Patricia J. [Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Klopp, Ann H., E-mail: aklopp@mdanderson.org [Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States)

    2014-02-01

    Purpose: To determine the incidence of duodenal toxicity in patients receiving intensity modulated radiation therapy (IMRT) for treatment of para-aortic nodes and to identify dosimetric parameters predictive of late duodenal toxicity. Methods and Materials: We identified 105 eligible patients with gynecologic malignancies who were treated with IMRT for gross metastatic disease in the para-aortic nodes from January 1, 2005, through December 31, 2009. Patients were treated to a nodal clinical target volume to 45 to 50.4 Gy with a boost to 60 to 66 Gy. The duodenum was contoured, and dosimetric data were exported for analysis. Duodenal toxicity was scored according to Radiation Therapy Oncology Group criteria. Univariate Cox proportional hazards analysis and recursive partitioning analysis were used to determine associations between dosimetric variables and time to toxicity and to identify the optimal threshold that separated patients according to risk of toxicity. Results: Nine of the 105 patients experienced grade 2 to grade 5 duodenal toxicity, confirmed by endoscopy in all cases. The 3-year actuarial rate of any duodenal toxicity was 11.7%. A larger volume of the duodenum receiving 55 Gy (V55) was associated with higher rates of duodenal toxicity. The 3-year actuarial rates of duodenal toxicity with V55 above and below 15 cm{sup 3} were 48.6% and 7.4%, respectively (P<.01). In Cox univariate analysis of dosimetric variables, V55 was associated with duodenal toxicity (P=.029). In recursive partitioning analysis, V55 less than 13.94% segregated all patients with duodenal toxicity. Conclusions: Dose-escalated IMRT can safely and effectively treat para-aortic nodal disease in gynecologic malignancies, provided that care is taken to limit the dose to the duodenum to reduce the risk of late duodenal toxicity. Limiting V55 to below 15 cm{sup 3} may reduce the risk of duodenal complications. In cases where the treatment cannot be delivered within these constraints

  17. Radioisotopes and vertebral augmentation: dosimetric analysis of a novel approach for the treatment of malignant compression fractures.

    Science.gov (United States)

    Hirsch, Ariel E; Medich, David C; Rosenstein, Barry S; Martel, Christopher B; Hirsch, Joshua A

    2008-04-01

    Vertebral compression fractures (VCFs), a major cause of morbidity and debilitating pain, often results from secondary tumor metastases to the skeleton. Vertebral augmentation is a palliative technique developed to treat VCFs and involves the injection of polymethyl methacrylate (PMMA) to augment the fractured vertebral body. The authors investigate the feasibility of radionuclide therapy coupled with vertebral augmentation to treat both the tumor metastases and VCFs. Six therapeutic radioisotopes, uniformly mixed in a PMMA bolus, were investigated for their dosimetric properties. The MCNP5 Monte Carlo computer code was used to characterize the therapeutic dosimetric distribution within a cortical bone phantom for a 1 mm radial bolus of isotope-infused PMMA. Based on these data, the minimum activity required for a therapeutic treatment was calculated. The dosimetry from beta emitting Y-90, P-32, and Ho-166 decreased to 10% of its maximum therapeutic dose (R10%) after traveling 1.20 mm, 1.03 mm, and 0.97 mm, respectively, through cortical bone. Low photon energy I-125 had a slightly larger calculated R10% of 1.32 mm. Although F-18 and Tc-99m exhibited a more uniform distribution (R10%=1.72 mm and 1.94 mm, respectively), the lower dosimetric gradients resulted in significantly greater therapeutic implant activities relative to the other isotopes studied in this report. Radionuclide therapy coupled with vertebral augmentation is shown to be a feasible technique for the treatment of secondary skeletal metastases and its resulting side effects. Future studies will include a full clinical investigation to determine optimal treatment isotope(s).

  18. Dosimetric of extremities with Dosemeters thermoluminescent in Cuba

    International Nuclear Information System (INIS)

    Molina Perez, D.; Diaz Bernal, E.; Vera Alonso, L.

    1998-01-01

    From final of the year 1995 in the CPHR implement the service of monitoring of the extremities using Dosemeter thermoluminescent (TL). The dosemeter consists on a metallic ring with a circular hole where a detector of LiF:Mg,Ti is placed (model JR1152C) of 5x5x0.9 mm 3 , covered by a fine layer of polyethylene. In the work the characteristic dosimetric as of the dosemeter is studied it satisfies the main requirements for their use in the monitoring from the exhibition to radiation photonic of the extremities. The doses are also presented registered during the first two years of operation of the service. The results obtained until the moment point out to you practice them of nuclear medicine, radiotherapy and production of substances radioactive how as of more contribution

  19. Dosimetric commissioning of a CBCT system for IGRT purposes

    International Nuclear Information System (INIS)

    Alfonso, R.; Ascencion, Y.; Castillo, D.; Linares, H.; Argota, R.; Garcia, F.

    2015-01-01

    During the last few years the use of tomographic imaging systems based on kilo voltage, cone shaped photon beams (kV-CBCT) for ensuring an accurate positioning of patients in radiotherapy treatments has expanded to low income departments, such as those existing in public health systems of low and middle income countries (LMIC). Although several dosimetric studies have been published so far, showing results of collateral dose in patients exposed to kV-CBCT studies for image guidance radiotherapy purposes (IGRT), their main objective is to demonstrate that these doses are significantly lower than the prescribed dose to the target volume and even the dose to organs and healthy tissues. In the actual study a methodology is proposed to reduce the CBCT dose during IGRT procedures for tumor targets located in the thorax region, where motion management is crucial. Criteria for dose optimization, based on image quality indexes and automated positioning accuracy, were implemented. (Author)

  20. Dosimetric aspects of radiolabeled antibodies for tumor therapy

    International Nuclear Information System (INIS)

    Humm, J.L.

    1986-01-01

    Radioimmunotherapy (RIT) is rapidly attracting interest as a potential new weapon in the arsenal for cancer therapy. This article concentrates on some of the dosimetric aspects affecting the potential success of RIT, and examines factors which influence the choice of a radiolabel for RIT. No radionuclide is likely to give an optimum tumor/nontumor insult for all tumor types; therefore, the concept of matching the source to tumor morphology is introduced. Lists of candidate radionuclides are given, classified according to the type of decay, range, and energy of the emission. The article examines how the choice of radionuclide for radiolabeling the antibody affects the local energy deposition in the tumor. Both the effect of tumor size on the energy absorbed fraction and the problem of antibody binding heterogeneity are discussed. The approach to RIT is to relate the choice of radionuclide to the physical properties of the tumor. 26 references

  1. Dosimetric analysis of radiation sources to use in dermatological lesions

    International Nuclear Information System (INIS)

    Tada, Ariane

    2010-01-01

    Skin lesions undergoing therapy with radiation sources may have different patterns of malignancy. Malignant lesions or cancer most commonly found in radiotherapy services are carcinomas. Radiation therapy in skin lesions is performed with low penetration beams and orthovoltage X-rays, electron beams and radioactive sources ( 192 Ir, 198 Au, e 90 Sr) arranged on a surface mold or in metal applicator. This study aims to analyze the therapeutic radiation dose profile produced by radiation sources used in skin lesions radiotherapy procedures. Experimental measurements for the analysis of dosimetric radiation sources were compared with calculations obtained from a computer system based on the Monte Carlo Method. Computational results had a good agreement with the experimental measurements. Experimental measurements and computational results by the MCNP4C code have been used to validate the calculations obtained by MCNP code and to provide a reliable medical application for each clinical case. (author)

  2. Dosimetric properties of the fast neutron therapy beams at TAMVEC

    International Nuclear Information System (INIS)

    Almond, P.R.; Smith, A.R.; Smathers, J.R.; Otte, V.A.

    1975-01-01

    In October 1972, M.D. Anderson Hospital and Tumor Institute of the University of Texas System Cancer Center initiated a clinical trial of fast neutron radiotherapy using the cyclotron at Texas A and M University. Initially, the study used neutrons produced by bombarding beryllium with 16 MeV deuterons, but since March, 1973, neutrons from 50 MeV deuterons have been used. The dosimetric properties of the 30 MeV beams have also been measured for comparison with the neutron beams from D-T generators. The three beams are compared in terms of dose rate, skin sparing, depth dose and field flatness. Isodose curves for treatment planning were generated using the decrement line method and compared to curves measured by a computer controlled isodose plotter. This system was also used to measure the isodose curves for wedge fields. Dosimetry checks on various patients were made using silicon diodes as in vivo fast neutron dosimeters

  3. Toward a nomenclature and dosimetric scheme applicable to all radiations

    International Nuclear Information System (INIS)

    Rupert, C.S.; Latarjet, R.

    1978-01-01

    An informal Joint Working Group on Radiation Quantities, consisting of representatives of the ICRU and other international organizations was initiated at the International Congress of Radiation Research in 1974. The conclusions of a meeting of the Group held in 1975 are summarised. Quantities are proposed to describe any type of radiation field in terms of the total amount of energy carried by the radiation and its distribution with respect to time, area, volume and solid angle, expressed in terms of either radiant energy (joules) or number of particles. If this general approach is agreed to by the parent organizations and others the Group will go on to recommend quantities to represent the interactions of fields with matter and to provide a dosimetric scheme usable with all types of radiation. (author)

  4. A dosimetric study during cardiac angiography in young children

    International Nuclear Information System (INIS)

    Amiel, M.; Clermont, A.; Jocteur-Monrozier, D.; Moroni, J.P.; Brun, P.

    1976-01-01

    A dosimetric study was carried out in collaboration with the SCPRI in 30 infants during cardiac catheterization for a congenital cardiopathy. As far as the doctor is concerned, the results show that the dose received by the right hand of the operator is the only one that is relatively high and notably higher than in the adult; the other results are in agreement with those published in the literature. For the manipulator the doses received are practically negligible. This finding does not agree with those of certain publications in the literature and it emphasizes the importance of the working conditions for these personnel. For infants, the gonadal dose is much higher than in the adult and the magnitude of the dose relative to the dose at the place of entry of the incident beam, taking into account the weight of the infant, certaintly represents a long-term risk, in particular, in patients who must undergo repeated examinations [fr

  5. A biokinetic and dosimetric model for the metabolism of uranium

    International Nuclear Information System (INIS)

    Wrenn, M.E.; Bertelli, L.; Durbin, P.W.; Eckerman, K.F.; Lipsztein, J.L.; Singh, N.P.

    1995-10-01

    Experiments involving injection and inhalation of uranium compounds into several animal species as well as those associated with humans are described and analyzed. A revised biokinetic and dosimetric model for the metabolism of uranium suitable for bioassay procedures is proposed. The model consists of a systematic part coupled to a model of the respiratory tract. The model has been tested against human data which incorporates in vivo measurements over the chest and measurements of urine, feces, and autopsy and biopsy samples.In particular the lung model of the International Commission on Radiological Protection, Publication 30 ( ICRP-30 ), has been modified in order to provide a model which more nearly predicts urinary excretion in accord with the experiences in humans and animals. We have also tested the data against the new ICRP (LUDEP) lung model. (author). 55 refs., 14 tabs., 33 figs

  6. Dosimetric comparison between techniques for irradiation of breast plastron

    International Nuclear Information System (INIS)

    Trinca, W.C.; Bruning, F.F.; Caldeira, F A.M.; Silveira, T.B da; Batista, D.V.S.; Andrade, R.R.

    2009-01-01

    Patients with breast cancer undergoing radical mastectomy has as an indication of adjuvancy the irradiation of the breast plastron. This paper makes a comparison between different techniques for treatment of breast plastron routinely used in the National Cancer Institute of Brazil (INCA): The irradiation with tangential fields of photons at 6 MV linear accelerator and irradiation with direct angled fields of electron beams of 6 and 9 MeV. We performed dosimetric comparisons in a tissue-equivalent phantom with the use of radiochromic films for verification of coverage and homogeneity of dose for all technical requirements. Tangential fields in the coverage and homogeneity were satisfactory and well cover the clinical aspects as well as beam 9 MeV, despite a small loss at the edge of the external field. Already in 6 MeV beam, there was significant loss in the end, with significant subdoses of 3 cm in the last field. (author)

  7. Radiation hazards in uranium mining. Epidemiological and dosimetric approaches

    International Nuclear Information System (INIS)

    Myers, D.K.; Johnson, J.R.

    1989-01-01

    Potential health hazards resulting from exposure to various sources of radiation associated with uranium mining have been reviewed: 1) epidemiological observations on groups of miners exposed in the past to high concentrations of radon progeny have been interpreted to suggest a lifetime risk of about 3 x 10 -4 lung cancers per WLM; 2) the total risk of serious health effects resulting from exposure of workers to whole body gamma-radiation might be taken to be about 2 x 10 -2 per Sv; and 3) the potential health effects of inhalation of thoron progeny or of radioactive ore dusts can only be estimated from dosimetric calculations. A review of the uncertainties involved in these calculations suggests that ICRP estimates of the potential toxicity of inhaled thoron progeny are as good as those for inhaled radon progeny. However, the potential health hazards from inhaled uranium and thorium ore dusts have probably been overestimated by a factor of 2 to 10-fold

  8. Representing the dosimetric impact of deformable image registration errors

    Science.gov (United States)

    Vickress, Jason; Battista, Jerry; Barnett, Rob; Yartsev, Slav

    2017-09-01

    Deformable image registration (DIR) is emerging as a tool in radiation therapy for calculating the cumulative dose distribution across multiple fractions of treatment. Unfortunately, due to the variable nature of DIR algorithms and dependence of performance on image quality, registration errors can result in dose accumulation errors. In this study, landmarked images were used to characterize the DIR error throughout an image space and determine its impact on dosimetric analysis. Ten thoracic 4DCT images with 300 landmarks per image study matching the end-inspiration and end-expiration phases were obtained from ‘dir-labs’. DIR was performed using commercial software MIM Maestro. The range of dose uncertainty (RDU) was calculated at each landmark pair as the maximum and minimum of the doses within a sphere around the landmark in the end-expiration phase. The radius of the sphere was defined by a measure of DIR error which included either the actual DIR error, mean DIR error per study, constant errors of 2 or 5 mm, inverse consistency error, transitivity error or the distance discordance metric (DDM). The RDUs were evaluated using the magnitude of dose uncertainty (MDU) and inclusion rate (IR) of actual error lying within the predicted RDU. The RDU was calculated for 300 landmark pairs on each 4DCT study for all measures of DIR error. The most representative RDU was determined using the actual DIR error with a MDU of 2.5 Gy and IR of 97%. Across all other measures of DIR error, the DDM was most predictive with a MDU of 2.5 Gy and IR of 86%, closest to the actual DIR error. The proposed method represents the range of dosimetric uncertainty of DIR error using either landmarks at specific voxels or measures of registration accuracy throughout the volume.

  9. EPR dosimetric properties of nano-barium sulfate

    International Nuclear Information System (INIS)

    Aboelezz, E.; Hassan, G.M.; Sharaf, M.A.; El-Khodary, A.

    2015-01-01

    Nano/micro BaSO 4 were prepared through the co-precipitation method to measure ionizing radiation doses using electron paramagnetic resonance (EPR). The nano-BaSO 4 sample was characterized using X-ray diffraction (XRD), and transmission electron microscopy (TEM) techniques. The dose response and fading properties of nano- and micro-phase BaSO 4 were compared in EPR spectra. The prepared nano- and micro-BaSO 4 samples have the same hole and electron centers, which may be attributed to SO 4 − and SO 3 − , respectively. The dosimetric signals for prepared nano- and micro-BaSO 4 have spectroscopic splitting factor (g) with values 2.0025±0.0006 and 2.0027±0.0006, respectively. The nanocrystalline sample has a linear γ-ray dose response over the range 0.4 Gy–1 kGy. The performance parameters which including detection limit and critical level calculated from weighted and unweighted least-squares fitting. The sensitivity of nano-BaSO 4 to γ-ray is one and a half times more than alanine. The lifetime and activation energy for nano-BaSO 4 were estimated by conducting a thermal stability study, and were 5.7±1.1×10 4 years and 0.73±0.14 eV, respectively. The combined and expanded uncertainties accompanying measurements were ±3.89% and ±7.78%, respectively. - Highlights: • Preparation of nano-BaSO 4 using the co-precipitation method. • Study of the dosimetric properties of nano-barium sulfate using the EPR technique. • Comparison between a new EPR dosimeter using nano-materials and standard alanine. • Calculation of the uncertainty budget for nano-BaSO 4

  10. Dosimetric explanations of fatigue in head and neck radiotherapy: An analysis from the PARSPORT Phase III trial

    International Nuclear Information System (INIS)

    Gulliford, Sarah L.; Miah, Aisha B.; Brennan, Sinead; McQuaid, Dualta; Clark, Catharine H.; Partridge, Mike; Harrington, Kevin J.; Morden, James P.; Hall, Emma; Nutting, Christopher M.

    2012-01-01

    Background: An unexpected finding from the phase III parotid sparing radiotherapy trial, PARSPORT (ISRCTN48243537, CRUK/03/005), was a statistically significant increase in acute fatigue for those patients who were treated with intensity-modulated radiotherapy (IMRT) compared to standard conventional radiotherapy (CRT). One possible explanation was the difference in dose to central nervous system (CNS) structures due to differing beam portals. Using data from the trial, a dosimetric analysis of individual CNS structures was performed. Method: Dosimetric and toxicity data were available for 67 patients (27 CRT, 40 IMRT). Retrospective delineation of the posterior fossa, brainstem, cerebellum, pituitary gland, pineal gland, hypothalamus, hippocampus and basal ganglia was performed. Dosimetry was reviewed using summary statistics and dose–volume atlases. Results: A statistically significant increase in maximum and mean doses to each structure was observed for patients who received IMRT compared to those who received CRT. Both maximum and mean doses were significantly higher for the posterior fossa, brainstem and cerebellum for the 42 patients who reported acute fatigue of Grade 2 or higher (p ⩽ 0.01) compared to the 25 who did not. Dose–volume atlases of the same structures indicated that regions representing larger volumes and higher doses to each structure were consistent with a higher incidence of acute fatigue. There was no association between the dose distribution and acute fatigue for the other structures tested. Conclusions: The excess fatigue reported in the IMRT arm of the trial may, at least in part, be attributed to the dose distribution to the posterior fossa, cerebellum and brainstem. Future studies that modify dose delivery to these structures may allow us to test the hypothesis that radiation-induced fatigue is avoidable.

  11. Implications of Overweight Onset and Persistence for Social and Behavioral Development between Kindergarten Entry and Third Grade

    Science.gov (United States)

    Gable, Sara; Krull, Jennifer L.; Chang, Yiting

    2009-01-01

    The current study examines the social and behavioral development of school-age children with different histories of overweight onset. Eight thousand children from the Early Childhood Longitudinal Study-Kindergarten Cohort (ECLS-K) participated. Three groups of children were identified for analysis: (1) those who were persistently overweight from…

  12. The Effects of Social Relationships, Writing Media, and Microgenetic Development on First-Grade Students' Written Narratives.

    Science.gov (United States)

    Jones, Ithel; Pellegrini, A. D.

    1996-01-01

    Studied effects of social relationships, writing media, and microgenetic development on written narratives with 20 first graders in a within-subjects design. Results show that narratives composed with a word processor are lexically denser and more cohesive than those written in pencil. The facilitative effects of computer-supported writing are…

  13. The Impact of Cooperative Learning on Developing the Sixth Grade Students Decision-Making Skill and Academic Achievement

    Science.gov (United States)

    Asha, Intisar K.; Al Hawi, Asma M.

    2016-01-01

    This study aimed at investigating the effect of cooperative learning on developing the sixth graders' decision making skill and their academic achievement. The study sample, which was selected randomly, consisted of (46) students and divided into two groups: the experimental group that taught using the cooperative learning strategy and the control…

  14. Identifying the Dimensionality of Oral Language Skills of Children with Typical Development in Preschool through Fifth Grade

    Science.gov (United States)

    Lonigan, Christopher J.; Milburn, Trelani F.

    2017-01-01

    Purpose: Language is a multidimensional construct from prior to the beginning of formal schooling to near the end of elementary school. The primary goals of this study were to identify the dimensionality of language and to determine whether this dimensionality was consistent in children with typical language development from preschool through 5th…

  15. Curriculum Opportunities for Number Sense Development: A Comparison of First-Grade Textbooks in China and the United States

    Science.gov (United States)

    Cheng, Qiang; Wang, Jian

    2012-01-01

    As a key concept in early mathematics curriculum, number sense is crucial for children's learning of other mathematics concepts. An earlier curriculum with a strong focus on number sense development presumably helps children perform better in mathematics later on. Chinese students outperformed their United States (U.S.) peers on number sense at…

  16. Development and Validation of an Instrument to Assess Student Attitudes toward Science across Grades 5 through 10

    Science.gov (United States)

    Summers, Ryan; Abd-El-Khalick, Fouad

    2018-01-01

    The aim of the present study is to enable future studies into students' attitudes toward science, and related constructs, by developing and validating an instrument suitable for cross-sectional designs. Following a thorough review of the literature it was determined that many extant instruments included design aspects that appeared to be limited…

  17. Teachers' Use of Linguistic Scaffolding to Support the Academic Language Development of First-Grade Emergent Bilingual Students

    Science.gov (United States)

    Lucero, Audrey

    2014-01-01

    Research suggests that teachers need to scaffold emergent bilingual students as they develop the complex language associated with school success. This may especially be true in dual language settings, where children are learning two languages simultaneously. In this study, therefore, I investigate the linguistic scaffolding practices of…

  18. Validation of a paper-disk approach to facilitate the sensory evaluation of bitterness in dairy protein hydrolysates from a newly developed food-grade fractionation system.

    Science.gov (United States)

    Murray, Niamh M; O'Riordan, Dolores; Jacquier, Jean-Christophe; O'Sullivan, Michael; Cohen, Joshua L; Heymann, Hildegarde; Barile, Daniela; Dallas, David C

    2017-06-01

    Casein-hydrolysates (NaCaH) are desirable functional ingredients, but their bitterness impedes usage in foods. This study sought to validate a paper-disk approach to help evaluate bitterness in NaCaHs and to develop a food-grade approach to separate a NaCaH into distinct fractions, which could be evaluated by a sensory panel. Membrane filtration generated sensory evaluation. Bitterness differences observed in the membrane fractions using this sensory evaluation approach reflected those observed for the same fractions presented as a liquid. The flash-chromatography fractions increased in bitterness with an increase in hydrophobicity, except for the 50% EtOH fraction which had little bitterness. Amino acid analysis of the fractions showed enrichment of different essential amino acids in both the bitter and less bitter fractions. The developed food-grade fractionation system, allowed for a simple and reasonably scaled approach to separating a NaCaH, into physicochemically different fractions that could be evaluated by a sensory panel. The method of sensory evaluation used in this study, in which NaCaH samples are impregnated into paper-disks, provided potential solutions for issues such as sample insolubility and limited quantities of sample. As the impregnated paper-disk samples were dehydrated, their long storage life could also be suitable for sensory evaluations distributed by mail for large consumer studies. The research, in this study, allowed for a greater understanding of the physicochemical basis for bitterness in this NaCaH. As some essential amino acids were enriched in the less bitter fractions, selective removal of bitter fractions could allow for the incorporation of the less bitter NaCaH fractions into food products for added nutritional value, without negatively impacting sensory properties. There is potential for this approach to be applied to other food ingredients with undesirable tastes, such as polyphenols.

  19. Developing the conceptual instructional design with inquiry-based instruction model of secondary students at the 10th grade level on digestion system and cellular degradation issue

    Science.gov (United States)

    Rotjanakunnatam, Boonthida; Chayaburakul, Kanokporn

    2018-01-01

    The aims of this research study was to develop the conceptual instructional design with the Inquiry-Based Instruction Model (IBIM) of secondary students at the 10th grade level on Digestion System and Cellular Degradation issue using both oxygen and oxygen-degrading cellular nutrients were designed instructional model with a sample size of 45 secondary students at the 10th Grade level. Data were collected by asking students to do a questionnaire pre and post learning processes. The questionnaire consists of two main parts that composed of students' perception questionnaire and the questionnaire that asked the question answer concept for the selected questionnaire. The 10-item Conceptual Thinking Test (CTT) was assessed students' conceptual thinking evaluation that it was covered in two main concepts, namely; Oxygen degradation nutrients and degradation nutrients without oxygen. The data by classifying students' answers into 5 groups and measuring them in frequency and a percentage of students' performances of their learning pre and post activities with the Inquiry-Based Instruction Model were analyzed as a tutorial. The results of this research found that: After the learning activities with the IBIM, most students developed concepts of both oxygen and oxygen-degrading cellular nutrients in the correct, complete and correct concept, and there are a number of students who have conceptual ideas in the wrong concept, and no concept was clearly reduced. However, the results are still found that; some students have some misconceptions, such as; the concept of direction of electron motion and formation of the ATP of bioactivities of life. This cause may come from the nature of the content, the complexity, the continuity, the movement, and the time constraints only in the classroom. Based on this research, it is suggested that some students may take some time, and the limited time in the classroom to their learning activity with content creation content binding and

  20. Development of Real Time Operating System for Safety Grade PLC (POSAFE-Q) for Nuclear Power Plants

    Energy Technology Data Exchange (ETDEWEB)

    Son, Han Seong [ENESYS, Taejon (Korea, Republic of); Hwang, Sung Jae [POSCON, Seoul (Korea, Republic of); Lee, Young Joon; Kim, Chang Hwoi; Lee, Dong Young [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)

    2006-07-01

    POSAFE-Q is a newly developed programmable logic controller (PLC) in order to apply to digital safety system of nuclear power plants (NPP) according to Nuclear Power Plant safety requirements. POSAFE-Q hardware and software development process, including design, review, verification and validation, and configuration control and quality assurance, satisfies the requirements imposed by 10CFR50, Appendix B. This article introduces a real time operating system pCOS, which is the core of POSAFE-Q. Section 2 describes the structure of pCOS. Section 3 describes a few important features of pCOS, which are necessary to the application for the digital safety system of NPP.0.

  1. IPIP: A new approach to inverse planning for HDR brachytherapy by directly optimizing dosimetric indices

    OpenAIRE

    Pouliot, Jean; Cunha, Jason Adam; Hsu, I-Chow

    2011-01-01

    Purpose: Many planning methods for high dose rate (HDR) brachytherapy require an iterative approach. A set of computational parameters are hypothesized that will g ive a dose plan that meets dosimetric criteria. A dose plan is computed using these parameter

  2. The Development and Validation of an Instrument to Monitor the Implementation of Social Constructivist Learning Environments in Grade 9 Science Classrooms in South Africa

    Science.gov (United States)

    Luckay, Melanie B.; Laugksch, Rudiger C.

    2015-02-01

    This article describes the development and validation of an instrument that can be used to assess students' perceptions of their learning environment as a means of monitoring and guiding changes toward social constructivist learning environments. The study used a mixed-method approach with priority given to the quantitative data collection. During the quantitative data collection phase, a new instrument—the Social Constructivist Learning Environment Survey (SCLES)—was developed and used to collect data from 1,955 grade 9 science students from 52 classes in 50 schools in the Western Cape province, South Africa. The data were analysed to evaluate the reliability and validity of the new instrument, which assessed six dimensions of the classroom learning environment, namely, Working with Ideas, Personal Relevance, Collaboration, Critical Voice, Uncertainty in Science and Respect for Difference. Two dimensions were developed specifically for the present study in order to contextualise the questionnaire to the requirements of the new South African curriculum (namely, Metacognition and Respect for Difference). In the qualitative data collection phase, two case studies were used to investigate whether profiles of class mean scores on the new instrument could provide an accurate and "trustworthy" description of the learning environment of individual science classes. The study makes significant contributions to the field of learning environments in that it is one of the first major studies of its kind in South Africa with a focus on social constructivism and because the instrument developed captures important aspects of the learning environment associated with social constructivism.

  3. Dosimetric control: report of French submarine forces from 1989 to 1999

    International Nuclear Information System (INIS)

    Laroche, P.; Rousset, J.; Amabile, J.C.; Roe, H.

    2001-01-01

    We report on the Ile Longue strategic site and describe the medical and dosimetric monitoring of nuclear submarine crews. Over the past eleven years, dosimetric results of nuclear submarine crews have been gathered. We have compared these results to those of workers employed by outside enterprises and the directorate of naval constructions. During this period, neither the crew members nor the workers have been over-exposed. Considering each group, we show a more or less distinct diminution of equivalent doses. (authors)

  4. IPIP: A New Approach to Inverse Planning for HDR Brachytherapy by Directly Optimizing Dosimetric Indices

    OpenAIRE

    Siauw, Timmy; Cunha, Adam; Atamturk, Alper; Hsu, I-Chow; Pouliot, Jean; Goldberg, Ken

    2010-01-01

    Purpose: Many planning methods for high dose rate (HDR) brachytherapy treatment planning require an iterative approach. A set of computational parameters are hypothesized that will give a dose plan that meets dosimetric criteria. A dose plan is computed using these parameters, and if any dosimetric criteria are not met, the process is iterated until a suitable dose plan is found. In this way, the dose distribution is controlled by abstract parameters. The purpose of this study is to improve H...

  5. Closing the Discovery Learning Gap: A Leader Development Training Strategy for Company-Grade Officers for the Conduct of Stability and Reconstruction Operations

    National Research Council Canada - National Science Library

    Anderson, Erik N

    2006-01-01

    ...). However, current Institutional Domain education and training methods for company grade officers fail to adequately address the variety of challenges these officers face during operational deployments...

  6. Dosimetric evaluation of sucrose and granulated cane sugar in the therapeutic dose range.

    Science.gov (United States)

    Davidson, Melanie T M; Jordan, Kevin J

    2009-04-01

    Granulated cane sugar has been used as a dosimetric material to report dose in high dose accidental irradiations. The purpose of this study was to assess whether clinical dosimetry is also plausible with such a commonly available material. The behavior of cane sugar was explored with respect to therapeutically relevant radiation quantities (dose, dose rate) and qualities (energy, radiation type) as well as under different temperature conditions. The stability of the signal postirradiation was also measured. Absorbed dose was measured by spectrophotometric readout of a ferrous ammonium sulfate xylenol orange (FX)-sugar solution in 10 cm path length cells. A visible color change was produced as a function of dose when the irradiated sugar samples were dissolved in FX solution (10% dilution by mass). A comparison of the optical absorbance spectra and dose response of cane sugar with analytical grade sucrose was done to establish a benchmark standard from which subsequent dosimetry measurements can be validated. The response of the sugar dosimeter read at 590 nm was found to be linear over the dose range of 100-2000 cGy, independent of energy (6-18 MV) and of the average dose rate (100-500 cGy/min). The readout of sugar samples irradiated with mixed photon and electron fields was also shown to be independent of radiation type (photons and electrons). Sugar temperature (20-40 degrees C) during irradiation did not affect dose estimates, making it a promising dosimeter for in vivo dosimetry, particularly in cases where the dosimeter must remain in contact with the patient for an extended period of time. Sugar can be used as an integrating dosimeter, since it exhibits no fractionation effects. Granulated cane sugar is cost effective, safe, soft tissue equivalent, and can be used under various experimental conditions, making it a suitable dosimeter for some radiotherapy applications.

  7. Asterisk Grade Study Report.

    Science.gov (United States)

    Kokorsky, Eileen A.

    A study was conducted at Passaic County Community College (PCCC) to investigate the operation of a grading system which utilized an asterisk (*) grade to indicate progress in a course until a letter grade was assigned. The study sought to determine the persistence of students receiving the "*" grade, the incidence of cases of students receiving…

  8. Dosimetric Significance of the ICRP's Updated Guidance and Models, 1989-2003, and Implications for U.S. Federal Guidance

    Energy Technology Data Exchange (ETDEWEB)

    Leggett, R.W.

    2003-09-10

    Over the past two decades the U.S. Environmental Protection Agency (EPA) has issued a series of Federal guidance documents for the purpose of providing the Federal and State agencies with technical information to assist their implementation of radiation protection programs. Currently recommended dose conversion factors, annual limits on intake, and derived air concentrations for intake of radionuclides are tabulated in Federal Guidance Report No. 11 (FGR 11), published in 1988. The tabulations in FGR 11 were based on dosimetric quantities and biokinetic and dosimetric models of the International Commission on Radiological Protection (ICRP) developed for application to occupational exposures. Since the publication of FGR 11 the ICRP has revised some of its dosimetric quantities and its models for workers and has also developed age-specific models and dose conversion factors for intake of radionuclides by members of the public. This report examines the extent of the changes in the inhalation and ingestion dose coefficients of FGR 11 implied by the updated recommendations of the ICRP, both for workers and members of the public.

  9. Development of a model and computer code to describe solar grade silicon production processes. Fifth quarterly report

    Energy Technology Data Exchange (ETDEWEB)

    Srivastava, R.; Gould, R.K.

    1979-02-01

    This program aims at developing mathematical models, and computer codes based on these models, which will allow prediction of the product distribution in chemical reactors in which gaseous silicon compounds are converted to condensed-phase silicon. The reactors to be modeled are flow reactors in which silane or one of the halogenated silanes is thermally decomposed or reacted with an alkali metal, H/sub 2/ or H atoms. Because the product of interest is particulate silicon, processes which must be modeled, in addition to mixing and reaction of gas-phase reactants, include the nucleation and growth of condensed Si via coagulation, condensation, and heterogeneous reaction. During this report period computer codes were developed and used to calculate: (1) coefficients for Si vapor and Si particles describing transport due to concentration and temperature gradients (i.e., Fick and Soret diffusion, respectively), and (2) estimates of thermochemical properties of Si n-mers. The former are needed to allow the mass flux of Si to reactor walls to be calculated. Because of the extremely large temperature gradients that exist in some of the reactors to be used in producing Si (particularly the Westinghouse reactor), it was found that thermal (Soret) diffusion can be the dominant transport mechanism for certain sizes of Si particles. The thermochemical estimates are required to allow computation of the formation rate of Si droplets. With the completion of these calculations the information and coding of the particle routines in the modified LAPP code is at the point where debugging can be done and that is now in progress.

  10. Development and optimization of a modified process for producing the battery grade LiOH: Optimization of energy and water consumption

    International Nuclear Information System (INIS)

    Grágeda, Mario; González, Alonso; Alavia, Wilson; Ushak, Svetlana

    2015-01-01

    LiOH·H 2 O is used for preparation of alkaline batteries. The required characteristics of this compound are low levels of impurities and a specific particle size distribution. LiOH·H 2 O is produced from ore and brines. In northern Chile, lithium is produced from brines. This region presents particular desert climate conditions where water and energy are scarce. To help solve this problem, the conventional production process for battery grade LiOH·H 2 O was simulated and a modified process was developed, with an efficient consumption of energy and water, to improve the environmental sustainability of the plant, and greater process yield and product purity. Different configurations of the equipments were studied and for the best configurations the behavior of the modified process at different scenarios were simulated. It was found that the purity is independent of concentration used in feed to thickeners. The process yield increases in average 2.4% for modified process due to recycling operation. In modified process is obtained 28% more product mass, specific energy consumption decreases up to 4.8% and losses of Li/kg of product decreased by 83% compared to conventional process. The water consumption per kg of product in modified process is 1%–6.3%, being lower than in conventional process. The results presented can be considered as guidelines to address the optimization of the industrial process for obtaining the battery grade LiOH. - Highlights: • Water and energy are important resources in any sustainable industrial process. • High purity LiOH·H 2 O is a material for producing of lithium batteries. • Conventional and modified optimized processes for LiOH·H 2 O production were simulated. • Energy and water consumptions decrease for the modified process. • Optimal operational conditions of H 2 O, feed, pressure and energy were established

  11. Analysis of cursive letters, syllables, and words handwriting in a French second-grade child with Developmental Coordination Disorder and comparison with typically developing children

    Directory of Open Access Journals (Sweden)

    Caroline eJolly

    2014-01-01

    Full Text Available Poor handwriting is a core deficit in Developmental Coordination Disorder (DCD. In a previous study, we compared the evolution of cursive letters handwriting in a girl with DCD throughout her second-grade year with that of typically developing (TD children. We found that her handwriting evolved much less than that of TD children and remained similar to that of pre-schoolers at all stages, suggesting that her handwriting skills have reached a steady state level. We present here a continuation of this work, in which we focused on the velocity aspects of handwriting in another French child with DCD. Indeed, different velocity patterns have been observed in Chinese and English children with DCD. In the French cursive style of writing, consecutive letters are joined, a major difference with the English script style of writing. We thus analyzed the handwriting of a second-grade French girl with DCD, not only for isolated letters but also for syllables and words, in comparison to that of TD first-graders (6-7 years old; N=85 and second-graders (7-8 years old; N=88. Each written track was digitized, and nine kinematic parameters were measured to evaluate writing fluency. Results showed that the productions of the child with DCD were more similar to those of first-graders than to those of second-graders. In line with our previous study, the most discriminative parameters between the child with DCD and TD children were size and mean speed. Moreover, her handwriting was less fluent than that of TD children. In contrast to previous observations, we observed a higher writing velocity of the child with DCD when compared to TD children, whatever the complexity of the item, and no significant difference with TD children in the pausing time during writing. These differences may reflect linguistic specificities. For syllables and words, each letter was treated separately as a single unit, thus reflecting a problem in anticipation and automation.

  12. Development of the Graded Redefined Assessment of Strength, Sensibility and Prehension (GRASSP): reviewing measurement specific to the upper limb in tetraplegia.

    Science.gov (United States)

    Kalsi-Ryan, Sukhvinder; Curt, Armin; Verrier, Mary C; Fehlings, Michael G

    2012-09-01

    Primary outcome measures for the upper limb in trials concerning human spinal cord injury (SCI) need to distinguish between functional and neurological changes and require satisfying psychometric properties for clinical application. The Graded Redefined Assessment of Strength, Sensibility and Prehension (GRASSP) was developed by the International GRASSP Research and Design Team as a clinical outcome measure specific to the upper limbs for individuals with complete and incomplete tetraplegia (that is, paralysis or paresis). It can be administered across the continuum of recovery after acute cervical SCI. An international multicenter study (involving centers in North America and Europe) was conducted to apply the measure internationally and examine its applicability. The GRASSP is a multimodal test comprising 5 subtests for each upper limb: dorsal sensation, palmar sensation (tested with Semmes-Weinstein monofilaments), strength (tested with motor grading of 10 muscles), and prehension (distinguishes scores for qualitative and quantitative grasping). Thus, administration of the GRASSP results in 5 numerical scores that provide a comprehensive profile of upper-limb function. The established interrater and test-retest reliability for all subtests within the GRASSP range from 0.84 to 0.96 and from 0.86 to 0.98, respectively. The GRASSP is approximately 50% more sensitive (construct validity) than the International Standards of Neurological Classification of SCI (ISNCSCI) in defining sensory and motor integrity of the upper limb. The subtests show concurrence with the Spinal Cord Independence Measure (SCIM), SCIM self-care subscales, and Capabilities of Upper Extremity Questionnaire (CUE) (the strongest concurrence to impairment is with self-perception of function [CUE], 0.57-0.83, p rehabilitation, and outpatient clinics.

  13. Development and exploratory testing of a school-based educational program for healthy life behaviors among fifth grade children in South Korea.

    Science.gov (United States)

    Kim, Shin-Jeong; Baek, Seong-Sook; Kang, Kyung-Ah

    2017-01-01

    The purpose of this study was to develop an educational program to promote healthy life behaviors and to evaluate its potential effects on the health practices of fifth grade elementary school children. The program, which consisted of six categories (daily life and health, disease prevention and management, prevention of drug misuse and overuse, sexuality and health, mental health, and injury prevention and first aid), was developed based on the ADDIE model. A pretest-post-test, one-group, quasi-experimental design was used with 85 elementary school students who voluntarily participated in the program. A school-based educational program, called the "Six Kid Keys," referring to the six categories of healthy life behaviors, was developed. Significant pre-post differences in two of the six healthy life behavior categories (disease prevention and management, injury prevention and first aid) were found. A school-based intervention that was aimed at changing habits related to healthy life behaviors could be effective for elementary school children. © 2016 Japan Academy of Nursing Science.

  14. Development of API 5 CT grade P110 steel casing; Desenvolvimento de tubos casing API 5 CT grau P110

    Energy Technology Data Exchange (ETDEWEB)

    Kojima, Sergio Seijo; Roza, Juliana Espinossi

    2003-07-01

    This paper has as objective to discuss the results gotten in experiences carried through in industrial scale for the development of pipes class API 5CT P110 (1), with 244 mm of diameter and 12 mm of thickness. The pipes were welded longitudinally by process ERW (electric resistance welding) and submitted to quenching and tempering heat treatments. A C-Mn-Cr alloy with adequate quenching ability was used for the attainment of a martensite microstructure after quenching. The pipes at a temperature of 880 deg C were quenched in water and subsequently tempered at 515 deg C. The integrity of the weld region was evaluated through non destructive tests and flattening tests, Charpy impact tests and fracture toughness tests (CTOD). The pipes achieved the tension properties stipulated in the standard (yield strength bigger limit of 758 Mpa), and also the energy in the Charpy impact test (transversal), considering that the energy value obtained was 55 J (at 0 deg C) for base metal and 44 J in the weld metal. (author)

  15. Investigation of dosimetric characteristics of the high sensitivity LiF:Mg,Cu,P thermoluminescent dosemeter and its applications in diagnostic radiology

    Energy Technology Data Exchange (ETDEWEB)

    Fung, K.K.L

    2000-12-01

    The recent introduction and development of the thermoluminescent (T.L.) phosphor material LiF:Mg,Cu,P (usually named TLD100H or GR200A) has aroused intense interest of scientists in the field of radiation dosimetry due to its very favourable dosimetric characteristics. Both conventional LiF:Mg,Ti (TLD100) and LiF:Mg,Cu,P T.L. phosphors are tissue-equivalent but GR200A outperforms in respect of its very much higher sensitivity, by a factor of greater than 25, and a dose detection threshold of less than 1 {mu}Gy. A reproducible readout and annealing regime was developed in the initial part of this study with the newly installed automatic TLD (Thermoluminescence Dosimetry) apparatus in the X-ray and Radiation Physics Laboratories of the Hong Kong Polytechnic University. Basic dosimetric characteristics of this T.L. dosemeter (supplied by Harshaw-Bicron Co.) were then investigated. This paved the foundation for subsequent selected novel application studies in diagnostic radiology. Dosimetric characteristics which included linearity, reproducibility, batch uniformity, energy response, and minimum detectable dose were studied using X-rays in the commonly used diagnostic radiology energy range. Favourable dosimetric characteristics were observed from this T.L. phosphor, which agrees well with published studies. The effect of the number of thermal treatment cycles in the initialisation process on dosimetric properties of this T.L. phosphor was also investigated. This study exploits the favourable dosimetric properties of these T.L. dosemeters in some selected novel dosimetric applications in diagnostic radiology with an anthropomorphic phantom using facilities both in these laboratories and also in radiology departments of various district hospitals in Hong Kong. Radiation absorbed dose from the direct or scattered beam, at critical sites inside and on the surface of the phantom, were measured in these radiological studies. The special focus in some of these studies was to

  16. Gender effects on phonological processing and reading development in Northern Sotho children learning to read in English: A case study of Grade 3 learners

    Directory of Open Access Journals (Sweden)

    Carien Wilsenach

    2018-01-01

    Full Text Available Gender differences in reading development are a global phenomenon, with girls typically performing better than boys. Some studies have reported gender differences favouring girls in reading comprehension in South Africa, but little systematic evidence exists about gender differences in the cognitive-linguistic abilities that underlie reading development. This study investigated the effect of gender on phonological processing and reading development in Northern Sotho–English bilingual children. Grade 3 learners who received their literacy instruction in English were tested on various phonological processing and reading measures. Phonological awareness was assessed using phoneme isolation and elision tasks. Phonological working memory was assessed using memory for digits and non-word repetition tests while rapid automatised naming was tested using rapid letter, rapid digit, rapid object and rapid colour naming tasks. Reading achievement was assessed with various word reading tasks and with a fluent reading task. A multivariate analysis of variance revealed that gender had a significant effect on the phonological processing and reading abilities of Northern Sotho– English bilingual children. Girls performed significantly better than boys on all the reading measures, as well as on some aspects of phonological processing. The findings provide behavioural evidence in support of biological theories of gender differences, in that girls seemed to have developed some of the cognitive-linguistic skills associated with reading before boys. The girls also coped better with tasks that required increased cognitive processing. This study suggests that sex differences in reading development cannot be ignored in South Africa and need to be addressed in future curriculum development.

  17. [Melatonin as a marker of the grade of cardiac disorders during cachexia development in oncological patients of different ages].

    Science.gov (United States)

    Ballyuzek, M F; Mashkova, M V; Arutjunyan, A V; Duke, V A

    2017-01-01

    We have examined 103 patients at the age from 28 to 78 with the newly diagnosed oncological disease at stages II-IV before the beginning of anticancer treatment. The identification of the signs of the cachexia syndrome and its stage (pre-cachexia, cachexia) were carried out in the accordance with the CASCO criteria (2011) and taking into the account the age of the patients. The cardiovascular infringements were found to be comorbid to the oncological disease significantly more often in patients with signs of cachexia syndrome on the pre-cachexia stage and the total index of cardiovascular disorders in oncological patients increases with the severity of cachexia. In the course of the cachexia symptoms development the significant decline of melatonin excretion level (evaluated by the excretion of its main metabolite 6-sulfatoximelatonin level - aMT6s) in oncological patients was noted. The lowest changes in aMT6s levels were observed in patients older than 60 years, referred to the group of pre-cachexia, which may indicate the heterogeneity of the investigated groups as a result of the combination of manifestations of geriatric syndromes and cancer pathology. The possibility of false-positive diagnosis of pre-cachexia due to a combination of polygenic metabolic and age-related changes in elderly patients should be taken into account. Therefore, evaluation of melatonin excretion can be recommended as an additional marker in diagnosis and differential diagnosis of cachexia syndrome particularly in geriatric patients. A significant correlation between the occurrence and/or worsening of cardiac disease in cancer patients, cachexia symptoms and reduced level of aMT6s were revealed.

  18. Massachusetts Early Warning Indicator System (EWIS). "Technical Descriptions of Risk Model Development": Early and Late Elementary Age Groupings (Grades 1-6)

    Science.gov (United States)

    Massachusetts Department of Elementary and Secondary Education, 2013

    2013-01-01

    The Massachusetts Department of Elementary and Secondary Education (Department) created the grades 1-12 Early Warning Indicator System (EWIS) in response to district interest in the Early Warning Indicator Index (EWII) that the Department previously created for rising grade 9 students. Districts shared that the EWII data were helpful, but also…

  19. Massachusetts Early Warning Indicator System (EWIS). "Technical Descriptions of Risk Model Development": Middle and High School Age Groupings (Grades 7-12)

    Science.gov (United States)

    Massachusetts Department of Elementary and Secondary Education, 2013

    2013-01-01

    The Massachusetts Department of Elementary and Secondary Education (Department) created the grades 1-12 Early Warning Indicator System (EWIS) in response to district interest in the Early Warning Indicator Index (EWII) that the Department previously created for rising grade 9 students. Districts shared that the EWII data were helpful, but also…

  20. The Delphi Technique in Identifying Learning Objectives for the Development of Science, Technology and Society Modules for Palestinian Ninth Grade Science Curriculum

    Science.gov (United States)

    Abualrob, Marwan M. A.; Daniel, Esther Gnanamalar Sarojini

    2013-01-01

    This article outlines how learning objectives based upon science, technology and society (STS) elements for Palestinian ninth grade science textbooks were identified, which was part of a bigger study to establish an STS foundation in the ninth grade science curriculum in Palestine. First, an initial list of STS elements was determined. Second,…

  1. Design and dosimetric analysis of a 385 MHz TETRA head exposure system for use in human provocation studies.

    Science.gov (United States)

    Schmid, Gernot; Bolz, Thomas; Uberbacher, Richard; Escorihuela-Navarro, Ana; Bahr, Achim; Dorn, Hans; Sauter, Cornelia; Eggert, Torsten; Danker-Hopfe, Heidi

    2012-10-01

    A new head exposure system for double-blind provocation studies investigating possible effects of terrestrial trunked radio (TETRA)-like exposure (385 MHz) on central nervous processes was developed and dosimetrically analyzed. The exposure system allows localized exposure in the temporal brain, similar to the case of operating a TETRA handset at the ear. The system and antenna concept enables exposure during wake and sleep states while an electroencephalogram (EEG) is recorded. The dosimetric assessment and uncertainty analysis yield high efficiency of 14 W/kg per Watt of accepted antenna input power due to an optimized antenna directly worn on the subject's head. Beside sham exposure, high and low exposure at 6 and 1.5 W/kg (in terms of maxSAR10g in the head) were implemented. Double-blind control and monitoring of exposure is enabled by easy-to-use control software. Exposure uncertainty was rigorously evaluated using finite-difference time-domain (FDTD)-based computations, taking into account anatomical differences of the head, the physiological range of the dielectric tissue properties including effects of sweating on the antenna, possible influences of the EEG electrodes and cables, variations in antenna input reflection coefficients, and effects on the specific absorption rate (SAR) distribution due to unavoidable small variations in the antenna position. This analysis yielded a reasonable uncertainty of analysis. Copyright © 2012 Wiley Periodicals, Inc.

  2. Characterization and standardization of a thermoluminescent dosimetric system to ultraviolet and laser radiation using CaSO4:Dy

    International Nuclear Information System (INIS)

    Grossi, Fabio Henrique

    2002-01-01

    The photo transferred thermoluminescence (PTTL) was used to characterize a dosimetric system to the laser and ultraviolet radiation. Dysprosium activated calcium sulphate samples (CaSO 4 :Dy) used are produced at Instituto de Pesquisas Energeticas e Nucleares (IPEN) and have proved been an excellent dosimetric material for non ionizing radiation. PTTL signal was studied for UV radiation detection in the 220 to 450 nm range and for laser radiation in the 193 to 1.160 nm range. The samples presented more sensibility to the 193, 250, 310 and 337 nm wavelengths and no sensibility to infrared region. The samples presented linear PTTL in function of radiant exposure, excitation gamma dose in the range between 5 and 100 Gy and laser beam diameter between 2 and 6 nm. Another parameters studied were the angular dependence, UV lower exposure limit and PTTL signal optical fading. Spread laser radiation analysis was performed in the Ophthalmologic Department of Universidade Federal de Sao Paulo (UNIFESP) surgical center, showing that samples positioned as far as 4 m from laser source are sensitized to the laser radiation, as well as evaluating the laser exposure received by workers of medical area. A method to send the samples by mail was developed to the studies performed in the UNIFESP. (author)

  3. I.M.C.R.T. and prostate: dosimetric analysis; R.C.M.I. et prostate: analyse dosimetrique

    Energy Technology Data Exchange (ETDEWEB)

    Marchand, V.; Bourdin, S.; Rio, E.; Mahe, M. [Centre Rene-Gauducheau, Service de Radiotherapie, 44 - Saint-Herblain (France); Munos, C.; Lisbona, A. [Centre Rene-Gauducheau, Service de Physique Medicale, 44 - Saint-Herblain (France); Campion, L. [Centre Rene-Gauducheau, Dept. de Biostatistiques, 44 - Saint-Herblain (France)

    2007-11-15

    From this dosimetric descriptive analysis has been the feasibility of the dosimetric model respecting the criteria of the intensity modulated conformal radiotherapy (I.M.C.R.T.) for the coverage of the target volume and interindividual variability in volumes of the organs at risk. Full data of this continuous surveillance provide us information on the relevance of these dosimetric constraints and the role of the irradiated volume of organs a risk in terms of toxicity and quality of life. (N.C.)

  4. WE-AB-209-02: A New Inverse Planning Framework with Principle-Based Modeling of Inter-Structural Dosimetric Tradeoffs

    International Nuclear Information System (INIS)

    Liu, H; Dong, P; Xing, L

    2016-01-01

    Purpose: Traditional radiotherapy inverse planning relies on the weighting factors to phenomenologically balance the conflicting criteria for different structures. The resulting manual trial-and-error determination of the weights has long been recognized as the most time-consuming part of treatment planning. The purpose of this work is to develop an inverse planning framework that parameterizes the inter-structural dosimetric tradeoff among with physically more meaningful quantities to simplify the search for a clinically sensible plan. Methods: A permissible dosimetric uncertainty is introduced for each of the structures to balance their conflicting dosimetric requirements. The inverse planning is then formulated as a convex feasibility problem, which aims to generate plans with acceptable dosimetric uncertainties. A sequential procedure (SP) is derived to decompose the model into three submodels to constrain the uncertainty in the planning target volume (PTV), the critical structures, and all other structures to spare, sequentially. The proposed technique is applied to plan a liver case and a head-and-neck case and compared with a conventional approach. Results: Our results show that the strategy is able to generate clinically sensible plans with little trial-and-error. In the case of liver IMRT, the fractional volumes to liver and heart above 20Gy are found to be 22% and 10%, respectively, which are 15.1% and 33.3% lower than that of the counterpart conventional plan while maintaining the same PTV coverage. The planning of the head and neck IMRT show the same level of success, with the DVHs for all organs at risk and PTV very competitive to a counterpart plan. Conclusion: A new inverse planning framework has been established. With physically more meaningful modeling of the inter-structural tradeoff, the technique enables us to substantially reduce the need for trial-and-error adjustment of the model parameters and opens new opportunities of incorporating prior

  5. Spine Radiosurgery: A Dosimetric Analysis in 124 Patients Who Received 18 Gy

    International Nuclear Information System (INIS)

    Schipani, Stefano; Wen, Winston; Jin, Jain-Yue; Kim, Jin Koo; Ryu, Samuel

    2012-01-01

    Purpose: To define the safely tolerated doses to organs at risk (OARs) adjacent to the target volume (TV) of spine radiosurgery (SRS) with 18-Gy in a single fraction. Methods and Materials: A total of 124 patient cases with 165 spine metastases were reviewed. An 18-Gy single-fraction regimen was prescribed to the 90% isodose line encompassing the TV. A constraint of 10 Gy to 10% of the spinal cord outlined 6 mm above and below the TV was used. Dosimetric data to OARs were analyzed. Results: A total of 124 patients (100%) were followed-up, and median follow-up time was 7 months (1-50 months). Symptoms and local control were achieved in 114 patients (92%). Acute Radiation Therapy Oncology Group (RTOG) grade 1 oral mucositis occurred in 11 of 11 (100%) patients at risk for oropharyngeal toxicity after cervical spine treatment. There were no RTOG grade 2-4 acute or late complications. Median TV was 43.2 cc (5.3-175.4 cc) and 90% of the TV received median dose of 19 Gy (17-19.8 Gy). Median (range) of spinal cord maximum dose (Dmax), dose to spinal cord 0.35 cc (Dsc0.35), and cord volume receiving 10 Gy (Vsc10) were 13.8 Gy (5.4-21 Gy), 8.9 Gy (2.6-11.4 Gy) and 0.33 cc (0-1.6 cc), respectively. Other OARs were evaluated when in proximity to the TV. Esophagus (n=58), trachea (n=28), oropharynx (n=11), and kidneys (n=34) received median (range) V10 and V15 of 3.1 cc (0-5.8 cc) and 1.2 cc (0-2.9 cc), 2.8 cc (0-4.9 cc), and 0.8 cc (0-2.1 cc), 3.4 cc (0-6.2 cc) and 1.6 cc (0-3.2 cc), 0.3 cc (0-0.8 cc) and 0.08 cc (0-0.1 cc), respectively. Conclusions: Cord Dmax of 14 Gy and D0.35 of 10 Gy are safe dose constraints for 18-Gy single-fraction SRS. Esophagus V10 of 3 cc and V15 of 1 cc, trachea V10 of 3 cc, and V15 of 1 cc, oropharynx V10 of 3.5 cc and V15 of 1.5 cc, kidney V10 of 0.3 cc, and V15 of 0.1 cc are planning guidelines when these OARs are in proximity to the TV.

  6. Determination of trapping parameters of dosimetric thermoluminescent glow peak of lithium triborate (LiB{sub 3}O{sub 5}) activated by aluminum

    Energy Technology Data Exchange (ETDEWEB)

    Kafadar, V. Emir [University of Gaziantep, Department of Engineering Physics, 27310 Gaziantep (Turkey); Yazici, A. Necmeddin, E-mail: yazici@gantep.edu.t [University of Gaziantep, Department of Engineering Physics, 27310 Gaziantep (Turkey); Yildirim, R. Gueler [University of Gaziantep, Department of Engineering Physics, 27310 Gaziantep (Turkey)

    2009-07-15

    Lithium triborate (LBO) is a newly developed ideal nonlinear optical (NLO) crystal used in laser weapon, welder, radar, tracker, surgery, communication, etc. The effective atomic number (Z{sub eff}=7.3) makes it a tissue equivalent material and this encourages studies on its thermoluminescence (TL) properties for a radiation dosimetry. The previous studies have shown that Al-doped LiB{sub 3}O{sub 5} is a promising thermoluminescent dosimetric (TLD) material for dosimetric purposes and continuous and systematic investigations to improve its quality to get ones suited for dosimeter applications are worthy. In the given study, the additive dose (AD), initial rise with partial cleaning (IR), variable heating rate (VHR), peak shape (PS), three-points method (TPM) and computerized glow deconvolution (CGCD) methods were used to determine the kinetic parameters, namely the order of kinetics (b), activation energy (E{sub a}) and the frequency factor (s) associated with the dosimetric thermoluminescent glow peak (P3) of Al-doped LiB{sub 3}O{sub 5} after different dose levels with beta-irradiation.

  7. Dosimetric characterization of two radium sources for retrospective dosimetry studies

    Energy Technology Data Exchange (ETDEWEB)

    Candela-Juan, C., E-mail: ccanjuan@gmail.com [Radiation Oncology Department, La Fe University and Polytechnic Hospital, Valencia 46026, Spain and Department of Atomic, Molecular and Nuclear Physics, University of Valencia, Burjassot 46100 (Spain); Karlsson, M. [Division of Radiological Sciences, Department of Medical and Health Sciences, Linköping University, Linköping SE 581 85 (Sweden); Lundell, M. [Department of Medical Physics and Oncology, Karolinska University Hospital and Karolinska Institute, Stockholm SE 171 76 (Sweden); Ballester, F. [Department of Atomic, Molecular and Nuclear Physics, University of Valencia, Burjassot 46100 (Spain); Tedgren, Å. Carlsson [Division of Radiological Sciences, Department of Medical and Health Sciences, Linköping University, Linköping SE 581 85, Sweden and Swedish Radiation Safety Authority, Stockholm SE 171 16 (Sweden)

    2015-05-15

    Purpose: During the first part of the 20th century, {sup 226}Ra was the most used radionuclide for brachytherapy. Retrospective accurate dosimetry, coupled with patient follow up, is important for advancing knowledge on long-term radiation effects. The purpose of this work was to dosimetrically characterize two {sup 226}Ra sources, commonly used in Sweden during the first half of the 20th century, for retrospective dose–effect studies. Methods: An 8 mg {sup 226}Ra tube and a 10 mg {sup 226}Ra needle, used at Radiumhemmet (Karolinska University Hospital, Stockholm, Sweden), from 1925 to the 1960s, were modeled in two independent Monte Carlo (MC) radiation transport codes: GEANT4 and MCNP5. Absorbed dose and collision kerma around the two sources were obtained, from which the TG-43 parameters were derived for the secular equilibrium state. Furthermore, results from this dosimetric formalism were compared with results from a MC simulation with a superficial mould constituted by five needles inside a glass casing, placed over a water phantom, trying to mimic a typical clinical setup. Calculated absorbed doses using the TG-43 formalism were also compared with previously reported measurements and calculations based on the Sievert integral. Finally, the dose rate at large distances from a {sup 226}Ra point-like-source placed in the center of 1 m radius water sphere was calculated with GEANT4. Results: TG-43 parameters [including g{sub L}(r), F(r, θ), Λ, and s{sub K}] have been uploaded in spreadsheets as additional material, and the fitting parameters of a mathematical curve that provides the dose rate between 10 and 60 cm from the source have been provided. Results from TG-43 formalism are consistent within the treatment volume with those of a MC simulation of a typical clinical scenario. Comparisons with reported measurements made with thermoluminescent dosimeters show differences up to 13% along the transverse axis of the radium needle. It has been estimated that

  8. Dosimetric properties of textile fibers: application of electron paramagnetic resonance dosimetry to an accidental gamma irradiation

    International Nuclear Information System (INIS)

    Kamenopoulou, V.

    1988-01-01

    The dosimetric properties of some twenty textile fibers have been studied in order to develop a method for determining the dose received in the case of an accidental gamma irradiation. Three textile fibers having properties most closely satisfying our needs were selected for detailed investigations: cotton, polypropylene and quartz. Electron Paramagnetic Resonance (EPR) readout techniques were used. In order to eliminate spectral anisotropy problems due to textile fiber inhomogeneities, a system has been developed to rotate samples in the resonant cavity during measurements. The structure, physical and chemical properties of cotton and polypropylene were investigated. A bibliographic study of the combined effects of light, heat and ionizing radiation on textile fibers was carried out. A linear relation exists between the EPR signal and the gamma ray dose received over a certain dose range. A method has been developed for preparing samples so as to reduce background noise not due to irradiation; in this way the detection threshold is lowered and a greater time stability obtained. Unknown doses corresponding to known spectra are determined by linear interpolation using a series of spectra obtained from the same fabric irradiated with known doses [fr

  9. Analysis of Dosimetric Parameters Associated With Acute Gastrointestinal Toxicity and Upper Gastrointestinal Bleeding in Locally Advanced Pancreatic Cancer Patients Treated With Gemcitabine-Based Concurrent Chemoradiotherapy

    International Nuclear Information System (INIS)

    Nakamura, Akira; Shibuya, Keiko; Matsuo, Yukinori; Nakamura, Mitsuhiro; Shiinoki, Takehiro; Mizowaki, Takashi; Hiraoka, Masahiro

    2012-01-01

    Purpose: To identify the dosimetric parameters associated with gastrointestinal (GI) toxicity in patients with locally advanced pancreatic cancer (LAPC) treated with gemcitabine-based chemoradiotherapy. Methods and Materials: The data from 40 patients were analyzed retrospectively. Chemoradiotherapy consisted of conventional fractionated three-dimensional radiotherapy and weekly gemcitabine. Treatment-related acute GI toxicity and upper GI bleeding (UGB) were graded according to the Common Toxicity Criteria Adverse Events, version 4.0. The dosimetric parameters (mean dose, maximal absolute dose which covers 2 cm 3 of the organ, and absolute volume receiving 10–50 Gy [V 10–50 ]) of the stomach, duodenum, small intestine, and a composite structure of the stomach and duodenum (StoDuo) were obtained. The planning target volume was also obtained. Univariate analyses were performed to identify the predictive factors for the risk of grade 2 or greater acute GI toxicity and grade 3 or greater UGB, respectively. Results: The median follow-up period was 15.7 months (range, 4–37). The actual incidence of acute GI toxicity was 33%. The estimated incidence of UGB at 1 year was 20%. Regarding acute GI toxicity, a V 50 of ≥16 cm 3 of the stomach was the best predictor, and the actual incidence in patients with V 50 3 of the stomach vs. those with V 50 of ≥16 cm 3 was 9% vs. 61%, respectively (p = 0.001). Regarding UGB, V 50 of ≥33 cm 3 of the StoDuo was the best predictor, and the estimated incidence at 1 year in patients with V 50 3 of the StoDuo vs. those with V 50 ≥33 cm 3 was 0% vs. 44%, respectively (p = 0.002). The dosimetric parameters correlated highly with one another. Conclusion: The irradiated absolute volume of the stomach and duodenum are important for the risk of acute GI toxicity and UGB. These results could be helpful in escalating the radiation doses using novel techniques, such as intensity-modulated radiotherapy, for the treatment of pancreatic

  10. Analysis of Dosimetric Parameters Associated With Acute Gastrointestinal Toxicity and Upper Gastrointestinal Bleeding in Locally Advanced Pancreatic Cancer Patients Treated With Gemcitabine-Based Concurrent Chemoradiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Nakamura, Akira [Department of Radiation Oncology and Image-Applied Therapy, Kyoto University Graduate School of Medicine, Kyoto (Japan); Shibuya, Keiko, E-mail: kei@kuhp.kyoto-u.ac.jp [Department of Radiation Oncology and Image-Applied Therapy, Kyoto University Graduate School of Medicine, Kyoto (Japan); Matsuo, Yukinori; Nakamura, Mitsuhiro; Shiinoki, Takehiro; Mizowaki, Takashi; Hiraoka, Masahiro [Department of Radiation Oncology and Image-Applied Therapy, Kyoto University Graduate School of Medicine, Kyoto (Japan)

    2012-10-01

    Purpose: To identify the dosimetric parameters associated with gastrointestinal (GI) toxicity in patients with locally advanced pancreatic cancer (LAPC) treated with gemcitabine-based chemoradiotherapy. Methods and Materials: The data from 40 patients were analyzed retrospectively. Chemoradiotherapy consisted of conventional fractionated three-dimensional radiotherapy and weekly gemcitabine. Treatment-related acute GI toxicity and upper GI bleeding (UGB) were graded according to the Common Toxicity Criteria Adverse Events, version 4.0. The dosimetric parameters (mean dose, maximal absolute dose which covers 2 cm{sup 3} of the organ, and absolute volume receiving 10-50 Gy [V{sub 10-50}]) of the stomach, duodenum, small intestine, and a composite structure of the stomach and duodenum (StoDuo) were obtained. The planning target volume was also obtained. Univariate analyses were performed to identify the predictive factors for the risk of grade 2 or greater acute GI toxicity and grade 3 or greater UGB, respectively. Results: The median follow-up period was 15.7 months (range, 4-37). The actual incidence of acute GI toxicity was 33%. The estimated incidence of UGB at 1 year was 20%. Regarding acute GI toxicity, a V{sub 50} of {>=}16 cm{sup 3} of the stomach was the best predictor, and the actual incidence in patients with V{sub 50} <16 cm{sup 3} of the stomach vs. those with V{sub 50} of {>=}16 cm{sup 3} was 9% vs. 61%, respectively (p = 0.001). Regarding UGB, V{sub 50} of {>=}33 cm{sup 3} of the StoDuo was the best predictor, and the estimated incidence at 1 year in patients with V{sub 50} <33 cm{sup 3} of the StoDuo vs. those with V{sub 50} {>=}33 cm{sup 3} was 0% vs. 44%, respectively (p = 0.002). The dosimetric parameters correlated highly with one another. Conclusion: The irradiated absolute volume of the stomach and duodenum are important for the risk of acute GI toxicity and UGB. These results could be helpful in escalating the radiation doses using novel

  11. Recommendations for equipment requirements and specifications for digital and interventional radiology: Dosimetric aspects

    International Nuclear Information System (INIS)

    Suliman, I.I.; Zoetelief, J.

    2002-01-01

    The recognition of radiation induced injuries from fluoroscopically guided interventional procedures has resulted in the current demand for development of recommendations and standards to limit dose to both patients and staff. This paper outlines the recommendations drafted within the framework of European Project DIMOND III. The actual work involves survey and review of national and international documents as well as scientific publications in areas relevant to the digital and/or interventional radiology with an aim of developing recommendations for equipment requirements and specifications for digital and interventional radiology. A pilot study of experimental investigations in at least three hospitals will be conducted to test the requirements and the specifications, the result of which will be presented. The recommendations are expected to provide an effective means of dose reduction to both patients and staff while maintaining image quality adequate for the specific diagnosis or interventional procedure. Different components of x-ray systems that have direct impact on patient and staff doses have been considered. Where necessary a compromise between patient dose and image quality has been made. The dosimetric aspects of the recommendations propose detailed descriptions and limits to dosimetric information relevant to patient and staff doses. International recommendations on maximum patient entrance surface dose rate vary in the range from 25 to 65 mGy.min -1 for normal mode fluoroscopy. Maximum image intensifier or image receptor input dose rate around 0.1 Gy min -1 at a distance 30 cm from the image intensifier input surface has been generally recommended. Maximum fluoroscopic dose rate in air must not exceed 50 mGy.min -1 at a location depending on the configuration e.g. for undertable x-ray tube at 10 mm from the patient support on the patient side of the support. The use of pulsed fluoroscopy or low dose fluoroscopy is proposed as good options to minimize

  12. GRADE Guidelines: 16. GRADE evidence to decision frameworks for tests in clinical practice and public health

    NARCIS (Netherlands)

    Schünemann, Holger J.; Mustafa, Reem; Brozek, Jan; Santesso, Nancy; Alonso-Coello, Pablo; Guyatt, Gordon; Scholten, Rob; Langendam, Miranda; Leeflang, Mariska M.; Akl, Elie A.; Singh, Jasvinder A.; Meerpohl, Joerg; Hultcrantz, Monica; Bossuyt, Patrick; Oxman, Andrew D.; Singh, Jasvinder; Lange, Stefan; Parmelli, Elena; Moberg, Jenny; Rosenbaum, Sarah; Brignardello-Petersen, Romina; Wiercioch, Wojtek; Davoli, Marina; Nowak, Artur; Dietl, Bart

    2016-01-01

    Objectives: To describe the grading of recommendations assessment, development and evaluation (GRADE) interactive evidence to decision (EtD) frameworks for tests and test strategies for clinical, public health, or coverage decisions. Study Design and Setting: As part of the GRADE Working Group's

  13. GRADE Guidelines : 16. GRADE evidence to decision frameworks for tests in clinical practice and public health

    NARCIS (Netherlands)

    Schünemann, Holger J.; Mustafa, Reem A.; Brozek, Jan; Santesso, Nancy; Alonso-Coello, Pablo; Guyatt, Gordon; Scholten, Rob; Langendam, Miranda W; Leeflang, Mariska; Akl, Elie A.; Singh, Jasvinder A.; Meerpohl, Joerg; Hultcrantz, Monica; Bossuyt, Patrick Mm; Oxman, Andrew D.; Schünemann, Holger J.; Mustafa, Reem A.; Brozek, Jan; Santesso, Nancy; Alonso-Coello, Pablo; Scholten, Rob; Langendam, Miranda W; Bossuyt, Patrick Mm; Leeflang, Mariska; Singh, Jasvinder; Meerpohl, Joerg; Hultcrantz, Monica; Guyatt, Gordon; Oxman, Andrew D.; Lange, Stefan; Parmelli, Elena; Moberg, Jenny; Rosenbaum, Sarah; Brignardello-Petersen, Romina; Wiercioch, Wojtek; Davoli, Marina; Nowak, Artur; Dietl, Bart

    2016-01-01

    Objectives To describe the grading of recommendations assessment, development and evaluation (GRADE) interactive evidence to decision (EtD) frameworks for tests and test strategies for clinical, public health, or coverage decisions. Study Design and Setting As part of the GRADE Working Group's

  14. Development of the heap leaching of low-grade uranium ores for conditions of OJSC Priargunsky Mining and Chemical plant (PPGKhO)

    International Nuclear Information System (INIS)

    Morozov, A.; Litvinenko, V.

    2014-01-01

    The treatment of low-grade commercial uranium ores by heap leaching has been carried out at the enterprise since 1996. During the initial stage of development, the ore piles were formed of the raw ore having the run-of-mine coarseness with uranium content around 0.08%. Under such conditions, recovery of the metal to the solution is 60-65% in case of a pile treatment lasting 2 years. To intensify the process and to provide a stable concentration of uranium in the productive solutions transferred to sorption, the enterprise developed and implemented a method of percolation leaching of low-grade ores with re-circulation of productive solutions through the re-treated ore bulk (RF patent No. 2226564). The main peculiarity of such leaching is simultaneous moistening of the ore by productive solutions and by barren solutions that are sharpened with sulphuric acid; that gives the possibility to wet far bigger areas of piles under constant volume of productive solutions outputting to the sorption treatment. Such scheme enables to treat successively first the piles at the “re-treatment” (where the metal is mainly extracted), and then the piles at the “active leaching” stage (where the metal is mainly inside the ore bulk). The technical and economic indexes of the heap leaching of low-grade uranium ores were significantly increased in 2006, when the X-ray-radiometric treatment plant was commissioned. The technological scheme of ore treatment at the processing plant includes mould and grating of the raw material with delivery of undersized products enriched with uranium: -5 mm are transferred to the pulp process; fractions (-200+40) mm to the X-ray-radiometric separation; the material of size (-40+5) mm, washed-out from clayey and fine particles, are sent to the uranium heap leaching in piles. Delivery of the ore material having size (-40+5) mm to treatment by the acid leaching method excluded colmatage and creation of zones impermeable for water, and in combination

  15. A comprehensive approach to age-dependent dosimetric modeling

    Energy Technology Data Exchange (ETDEWEB)

    Leggett, R.W.; Cristy, M.; Eckerman, K.F.

    1986-01-01

    In the absence of age-specific biokinetic models, current retention models of the International Commission on Radiological Protection (ICRP) frequently are used as a point of departure for evaluation of exposures to the general population. These models were designed and intended for estimation of long-term integrated doses to the adult worker. Their format and empirical basis preclude incorporation of much valuable physiological information and physiologically reasonable assumptions that could be used in characterizing the age-specific behavior of radioelements in humans. In this paper we discuss a comprehensive approach to age-dependent dosimetric modeling in which consideration is given not only to changes with age in masses and relative geometries of body organs and tissues but also to best available physiological and radiobiological information relating to the age-specific biobehavior of radionuclides. This approach is useful in obtaining more accurate estimates of long-term dose commitments as a function of age at intake, but it may be particularly valuable in establishing more accurate estimates of dose rate as a function of age. Age-specific dose rates are needed for a proper analysis of the potential effects on estimates or risk of elevated dose rates per unit intake in certain stages of life, elevated response per unit dose received during some stages of life, and age-specific non-radiogenic competing risks.

  16. Active pixel as dosimetric device for interventional radiology

    International Nuclear Information System (INIS)

    Servoli, L.; Baldaccini, F.; Biasini, M.; Checcucci, B.; Chiocchini, S.; Cicioni, R.; Conti, E.; Di Lorenzo, R.; Dipilato, A.C.; Esposito, A.; Fanó, L.; Paolucci, M.; Passeri, D.; Pentiricci, A.

    2013-01-01

    Interventional Radiology (IR) is a subspecialty of radiology comprehensive of all minimally invasive diagnostic and therapeutic procedures performed using radiological devices to obtain image guidance. The interventional procedures are potentially harmful for interventional radiologists and medical staff due to the X-ray diffusion by the patient's body. The characteristic energy range of the diffused photons spans few tens of keV. In this work we will present a proposal for a new X-ray sensing element in the energy range of interest for IR procedures. The sensing element will then be assembled in a dosimeter prototype, capable of real-time measurement, packaged in a small form-factor, with wireless communication and no external power supply to be used for individual operators dosimetry for IR procedures. For the sensor, which is the heart of the system, we considered three different Active Pixel Sensors (APS). They have shown a good capability as single X-ray photon detectors, up to several tens keV photon energy. Two dosimetric quantities have been considered, the number of detected photons and the measured energy deposition. Both observables have a linear dependence with the dose, as measured by commercial dosimeters. The uncertainties in the measurement are dominated by statistic and can be pushed at ∼5% for all the sensors under test

  17. A comprehensive approach to age-dependent dosimetric modeling

    International Nuclear Information System (INIS)

    Leggett, R.W.; Cristy, M.; Eckerman, K.F.

    1986-01-01

    In the absence of age-specific biokinetic models, current retention models of the International Commission on Radiological Protection (ICRP) frequently are used as a point of departure for evaluation of exposures to the general population. These models were designed and intended for estimation of long-term integrated doses to the adult worker. Their format and empirical basis preclude incorporation of much valuable physiological information and physiologically reasonable assumptions that could be used in characterizing the age-specific behavior of radioelements in humans. In this paper we discuss a comprehensive approach to age-dependent dosimetric modeling in which consideration is given not only to changes with age in masses and relative geometries of body organs and tissues but also to best available physiological and radiobiological information relating to the age-specific biobehavior of radionuclides. This approach is useful in obtaining more accurate estimates of long-term dose commitments as a function of age at intake, but it may be particularly valuable in establishing more accurate estimates of dose rate as a function of age. Age-specific dose rates are needed for a proper analysis of the potential effects on estimates or risk of elevated dose rates per unit intake in certain stages of life, elevated response per unit dose received during some stages of life, and age-specific non-radiogenic competing risks

  18. Dosimetric intercomparison between protons and electrons therapies applied to retinoblastoma

    International Nuclear Information System (INIS)

    Braga, Flavia Vieira

    2008-01-01

    In this work we propose a construction of a simple human eye model in order to simulate the dosimetric response for a treatment with protons and electrons in a retinoblastoma cancer. The computational tool used in this simulation was the Geant4 code, in the version 4.9.1, all these package are free and permit simulate the interaction of radiation with matter. In our simulation we use a box with 4 cm side, with water, for represent the human eye. The simulation was performed considering mono energetics beams of protons and electrons with energy range between 50 and 70 MeV for protons and 2 and 10 MeV for electrons. The simulation was based on the advanced hadron therapy example of the Geant 4 code. In these example the phantom is divided in voxels with 0.2 mm side and it is generated the energy deposited in each voxel. The simulation results show the energy deliver in each voxel, with these energie we can calculate the dose deposited in that region. We can see the dose profile of, proton and electron, and we can see in both cases that for protons the position of delivered dose is well know, that happen in the position where the proton stop, for electrons the energies is delivered along the way and pass the desired position for high dose deposition. (author)

  19. Dosimetric implications of age related glandular changes in screening mammography

    International Nuclear Information System (INIS)

    Beckett, J.R.; Kotre, C.J.

    2000-01-01

    The UK National Health Service Breast Screening Programme is currently organized to routinely screen women between the ages of 50 and 64, with screening for older women available on request. The lower end of this age range closely matches the median age for the menopause (51 years), during which significant changes in the composition of the breast are known to occur. In order to quantify the dosimetric effect of these changes, radiographic factors and compressed breast thickness data for a cohort of 1258 women aged between 35 and 79 undergoing breast screening mammography have been used to derive estimates of breast glandularity and mean glandular dose (MGD), and examine their variation with age. The variation of mean radiographic exposure factors with age is also investigated. The presence of a significant number of age trial women within the cohort allowed an extended age range to be studied. Estimates of MGD including corrections for breast glandularity based on compressed breast thickness only, compressed breast thickness and age and for each individual woman are compared with the MGD based on the conventional assumption of a 50:50 adipose/glandular composition. It has been found that the use of the conventional 50:50 assumption leads to overestimates of MGD of up to 13% over the age range considered. By using compressed breast thickness to estimate breast glandularity, this error range can be reduced to 8%, whilst age and compressed breast thickness based glandularity estimates result in an error range of 1%. (author)

  20. Dosimetric properties of commercial glasses and sand for high doses

    International Nuclear Information System (INIS)

    Teixeira, Maria Ines

    2004-01-01

    Commercial glasses (transparent and colored) produced by Cebrace, Brazil, Sao Paulo, and sand samples of different Brazilian beaches were studied, due to their low cost and easy handling, to verify the possibility of their use in high dose dosimetry. The main dosimetric characteristics were determined using a densitometer, a spectrophotometer, a thermoluminescent (TL) reader and an electronic paramagnetic resonance system. The gamma irradiations were carried out using a Gamma-Cell 220 and a panoramic source ( 60 Co) of IPEN. An optical absorption band was observed at 420 nm in the glass samples. The TL glow curves presented peaks at 205 deg C, 135 deg C, 150 deg C and 145 deg C for the transparent, bronze, brown and green glass samples, respectively. All EPR spectra of the glasses showed Fe 3+ characteristic signals at g = 4.27 and 2.01. The gamma irradiated sand samples presented two peaks at 110 deg C and 170 deg C and an EPR signal at g= 1.999. However, these materials present a pronounced thermal fading at room temperature after irradiation. With the objective to minimize this thermal fading, both glass and sand samples were submitted to different pre- and post-irradiation thermal treatments. The glass and sand samples showed the possibility of utilization for high dose dosimetry and as Yes/No irradiation detectors. (author)

  1. Dosimetric analysis of radiation sources for use dermatological lesions

    International Nuclear Information System (INIS)

    Tada, Ariane

    2010-01-01

    Skin lesions undergoing therapy with radiation sources may have different patterns of malignancy. Malignant lesions or cancer most commonly found in radiotherapy services are carcinomas. Radiation therapy in skin lesions is performed with low penetration beams and orthovoltage X-rays, electron beams and radioactive sources ( 192 Ir, 198 Au, e 90 Sr) arranged on a surface mold or in metal applicator. This study aims to analyze the therapeutic radiation dose profile produced by radiation sources used in skin lesions radiotherapy procedures . Experimental measurements for the analysis of dosimetric radiation sources were compared with calculations obtained from a computer system based on the Monte Carlo Method. Computational results had a good agreement with the experimental measurements. Experimental measurements and computational results by the MCNP4C code were both physically consistent as expected. These experimental measurements compared with calculations using the MCNP-4C code have been used to validate the calculations obtained by MCNP code and to provide a reliable medical application for each clinical case. (author)

  2. Investigation of PBAT dosimetric properties for high gamma dose dosimetry

    International Nuclear Information System (INIS)

    Cunha, Elisete L.; Schimitberger, Thiago

    2017-01-01

    Poly(butylene adipate-co-terephthalate) (PBAT) is an aliphatic-aromatic copolyester which is biodegradable. It is a non-photoluminescent copolyester that becomes photoluminescent after previous exposure to gamma doses higher than 100 kGy. After the previous high energy irradiation, the material shows the highest photo-stimulated luminescence emission when excited with a LED source at wavelengths ranging from 370 to 405 nm. In this work we investigated the enhancement of the photoluminescence (PL) and dosimetric properties of PBAT, after exposure to high doses of gamma radiation ranging from 50 to 4,000 kGy. In this investigation we demonstrate that increasing the PBAT film thickness by 100 μm enhances the PL output by 3.5 times, when irradiated with 500 kGy. Also, besides the already known color green brightness, the PL intensity can also be used for high dose dosimetry purposes for doses ranging from 50 to 750 kGy. The FTIR analysis has demonstrated that the there is a linear relationship between peak intensity and dose for doses ranging from 100 and 2,000 kGy for the absorbance peaks at 3,241 cm -1 and 3271 cm -1 , with linear correlation coefficients of 0.9981 and 0.9992, respectively. The results indicate that PBAT has great potential for applications in bio-imaging devices and high gamma dose dosimetry. (author)

  3. Investigation of PBAT dosimetric properties for high gamma dose dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Cunha, Elisete L.; Schimitberger, Thiago, E-mail: elisete.cunha@cdtn.br [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Departamento de Engenharia Nuclear; Oliveira, Cristiana M.; Faria, Luiz O., E-mail: farialo@cdtn.br [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)

    2017-07-01

    Poly(butylene adipate-co-terephthalate) (PBAT) is an aliphatic-aromatic copolyester which is biodegradable. It is a non-photoluminescent copolyester that becomes photoluminescent after previous exposure to gamma doses higher than 100 kGy. After the previous high energy irradiation, the material shows the highest photo-stimulated luminescence emission when excited with a LED source at wavelengths ranging from 370 to 405 nm. In this work we investigated the enhancement of the photoluminescence (PL) and dosimetric properties of PBAT, after exposure to high doses of gamma radiation ranging from 50 to 4,000 kGy. In this investigation we demonstrate that increasing the PBAT film thickness by 100 μm enhances the PL output by 3.5 times, when irradiated with 500 kGy. Also, besides the already known color green brightness, the PL intensity can also be used for high dose dosimetry purposes for doses ranging from 50 to 750 kGy. The FTIR analysis has demonstrated that the there is a linear relationship between peak intensity and dose for doses ranging from 100 and 2,000 kGy for the absorbance peaks at 3,241 cm{sup -1} and 3271 cm{sup -1}, with linear correlation coefficients of 0.9981 and 0.9992, respectively. The results indicate that PBAT has great potential for applications in bio-imaging devices and high gamma dose dosimetry. (author)

  4. Dosimetric Uncertainties in Verification of Intensity Modulated Photon Beams

    International Nuclear Information System (INIS)

    Jurkovic, S.

    2010-01-01

    The doctoral thesis presents method for the calculation of the compensators' shape to modulate linear accelerators' beams. Characteristic of the method is more strict calculation of the scattered radiation in beams with an inhomogeneous cross-section than it was before. Method could be applied in various clinical situations. It's dosimetric verification was made in phantoms, measuring dose distributions using ionization chambers as well as radiographic film. Therefore, ionization chambers were used for the evaluation of modulator shape and film was used for the evaluation of two-dimensional dose distributions. It is well known that dosimetry of the intensity modulated photon beams is rather complicated regarding inhomogeneity of the dose distribution. The main reason for that is the beam modulator which changes spectral distribution of the beam. Possibility of use different types of detectors for the measurements of dose distributions in modulated photon beams and their accuracy were examined. Small volume ionization chambers, different diodes and amorphus silicon detector and radigraphic film were used. Measured dose distributions were compared between each other as well as with distributions simulated using Monte Carlo particle transport algorithm. In this way the most accurate method for the verification of modulate photon beams is suggested. (author)

  5. Synthesis and dosimetric characterization of LiF-MgF2, doped with Lu

    International Nuclear Information System (INIS)

    Gonzalez, Pedro R.; Nieto, Ana L.; Cruz-Zaragoza, Epifanio; Furetta, Claudio

    2013-01-01

    The results of the synthesis and characterization of dosimetric thermoluminescent material based on the composition LiF-MgF 2 1:1 (Z eff = 9.7) doped Lu 3+ ions, developed at the National Institute of Nuclear Research, Mexico are presented. The TL material synthesis was carried out using the technique of casting solid substances, preparations were made with dopant concentrations of 0.25, 0.83, 1.00 and 2.00 mol%, the 1 mol% resulted in increased sensitivity to radiation. Its brightness curve has the TL peak intensity at 330 deg C when irradiated to 1000 Gy, whereas when irradiated greater than 2500 Gy, occurs at 230 ° C, also has a peak of smaller maximum intensity at 140 ° C. Microstructural characterization of the obtained material was performed using the techniques of scanning electron microscopy and X-ray diffraction Kinetic parameters of the curves of brightness of the material is performed by the deconvolution method using the sequential quadratic programming algorithm, developed in the same institute. This new TL material complies fully with international standards to be used as dosimetry system in medical physics, research and industry, as its TL response (total integrated under the curve) to 60 Co gamma radiation, presents linearity between 1 and 5000 Gy , while the response of commercial TLD dosimeter-100 used as a reference, is only linear up to 10 Gy

  6. Gleason grading system

    Science.gov (United States)

    ... medlineplus.gov/ency/patientinstructions/000920.htm Gleason grading system To use the sharing features on this page, ... score of between 5 and 7. Gleason Grading System Sometimes, it can be hard to predict how ...

  7. Online dosimetric evaluation of larynx SBRT: A pilot study to assess the necessity of adaptive replanning.

    Science.gov (United States)

    Mao, Weihua; Rozario, Timothy; Lu, Weiguo; Gu, Xuejun; Yan, Yulong; Jia, Xun; Sumer, Baran; Schwartz, David L

    2017-01-01

    We have initiated a multi-institutional phase I trial of 5-fraction stereotactic body radiotherapy (SBRT) for Stage III-IVa laryngeal cancer. We conducted this pilot dosimetric study to confirm potential utility of online adaptive replanning to preserve treatment quality. We evaluated ten cases: five patients enrolled onto the current trial and five patients enrolled onto a separate phase I SBRT trial for early-stage glottic larynx cancer. Baseline SBRT treatment plans were generated per protocol. Daily cone-beam CT (CBCT) or diagnostic CT images were acquired prior to each treatment fraction. Simulation CT images and target volumes were deformably registered to daily volumetric images, the original SBRT plan was copied to the deformed images and contours, delivered dose distributions were re-calculated on the deformed CT images. All of these were performed on a commercial treatment planning system. In-house software was developed to propagate the delivered dose distribution back to reference CT images using the deformation information exported from the treatment planning system. Dosimetric differences were evaluated via dose-volume histograms. We could evaluate dose within 10 minutes in all cases. Prescribed coverage to gross tumor volume (GTV) and clinical target volume (CTV) was uniformly preserved; however, intended prescription dose coverage of planning treatment volume (PTV) was lost in 53% of daily treatments (mean: 93.9%, range: 83.9-97.9%). Maximum bystander point dose limits to arytenoids, parotids, and spinal cord remained respected in all cases, although variances in carotid artery doses were observed in a minority of cases. Although GTV and CTV SBRT dose coverage is preserved with in-room three-dimensional image guidance, PTV coverage can vary significantly from intended plans and dose to critical structures may exceed tolerances. Online adaptive treatment re-planning is potentially necessary and clinically applicable to fully preserve treatment

  8. Three-Dimensional Dosimetric Validation of a Magnetic Resonance Guided Intensity Modulated Radiation Therapy System

    Energy Technology Data Exchange (ETDEWEB)

    Rankine, Leith J., E-mail: Leith_Rankine@med.unc.edu [Department of Radiation Oncology, Washington University School of Medicine, St Louis, Missouri (United States); Department of Radiation Oncology, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina (United States); Mein, Stewart [Medical Physics Graduate Program, Duke University, Durham, North Carolina (United States); Cai, Bin; Curcuru, Austen [Department of Radiation Oncology, Washington University School of Medicine, St Louis, Missouri (United States); Juang, Titania; Miles, Devin [Medical Physics Graduate Program, Duke University, Durham, North Carolina (United States); Mutic, Sasa; Wang, Yuhe [Department of Radiation Oncology, Washington University School of Medicine, St Louis, Missouri (United States); Oldham, Mark [Medical Physics Graduate Program, Duke University, Durham, North Carolina (United States); Department of Radiation Oncology, Duke University Medical Center, Durham, North Carolina (United States); Li, H. Harold, E-mail: hli@radonc.wustl.edu [Department of Radiation Oncology, Washington University School of Medicine, St Louis, Missouri (United States)

    2017-04-01

    Purpose: To validate the dosimetric accuracy of a commercially available magnetic resonance guided intensity modulated radiation therapy (MRgIMRT) system using a hybrid approach: 3-dimensional (3D) measurements and Monte Carlo calculations. Methods and Materials: We used PRESAGE radiochromic plastic dosimeters with remote optical computed tomography readout to perform 3D high-resolution measurements, following a novel remote dosimetry protocol. We followed the intensity modulated radiation therapy commissioning recommendations of American Association of Physicists in Medicine Task Group 119, adapted to incorporate 3D data. Preliminary tests (“AP” and “3D-Bands”) were delivered to 9.5-cm usable diameter cylindrical PRESAGE dosimeters to validate the treatment planning system (TPS) for nonmodulated deliveries; assess the sensitivity, uniformity, and rotational symmetry of the PRESAGE dosimeters; and test the robustness of the remote dosimetry protocol. Following this, 4 clinical MRgIMRT plans (“MultiTarget,” “Prostate,” “Head/Neck,” and “C-Shape”) were measured using 13-cm usable diameter PRESAGE dosimeters. For all plans, 3D-γ (3% or 3 mm global, 10% threshold) passing rates were calculated and 3D-γ maps were examined. Point doses were measured with an IBA-CC01 ionization chamber for validation of absolute dose. Finally, by use of an in-house-developed, GPU-accelerated Monte Carlo algorithm (gPENELOPE), we independently calculated dose for all 6 Task Group 119 plans and compared against the TPS. Results: For PRESAGE measurements, 3D-γ analysis yielded passing rates of 98.7%, 99.2%, 98.5%, 98.0%, 99.2%, and 90.7% for AP, 3D-Bands, MultiTarget, Prostate, Head/Neck, and C-Shape, respectively. Ion chamber measurements were within an average of 0.5% (±1.1%) from the TPS dose. Monte Carlo calculations demonstrated good agreement with the TPS, with a mean 3D-γ passing rate of 98.5% ± 1.9% using a stricter 2%/2-mm criterion. Conclusions: We

  9. Three-Dimensional Dosimetric Validation of a Magnetic Resonance Guided Intensity Modulated Radiation Therapy System

    International Nuclear Information System (INIS)

    Rankine, Leith J.; Mein, Stewart; Cai, Bin; Curcuru, Austen; Juang, Titania; Miles, Devin; Mutic, Sasa; Wang, Yuhe; Oldham, Mark; Li, H. Harold

    2017-01-01

    Purpose: To validate the dosimetric accuracy of a commercially available magnetic resonance guided intensity modulated radiation therapy (MRgIMRT) system using a hybrid approach: 3-dimensional (3D) measurements and Monte Carlo calculations. Methods and Materials: We used PRESAGE radiochromic plastic dosimeters with remote optical computed tomography readout to perform 3D high-resolution measurements, following a novel remote dosimetry protocol. We followed the intensity modulated radiation therapy commissioning recommendations of American Association of Physicists in Medicine Task Group 119, adapted to incorporate 3D data. Preliminary tests (“AP” and “3D-Bands”) were delivered to 9.5-cm usable diameter cylindrical PRESAGE dosimeters to validate the treatment planning system (TPS) for nonmodulated deliveries; assess the sensitivity, uniformity, and rotational symmetry of the PRESAGE dosimeters; and test the robustness of the remote dosimetry protocol. Following this, 4 clinical MRgIMRT plans (“MultiTarget,” “Prostate,” “Head/Neck,” and “C-Shape”) were measured using 13-cm usable diameter PRESAGE dosimeters. For all plans, 3D-γ (3% or 3 mm global, 10% threshold) passing rates were calculated and 3D-γ maps were examined. Point doses were measured with an IBA-CC01 ionization chamber for validation of absolute dose. Finally, by use of an in-house-developed, GPU-accelerated Monte Carlo algorithm (gPENELOPE), we independently calculated dose for all 6 Task Group 119 plans and compared against the TPS. Results: For PRESAGE measurements, 3D-γ analysis yielded passing rates of 98.7%, 99.2%, 98.5%, 98.0%, 99.2%, and 90.7% for AP, 3D-Bands, MultiTarget, Prostate, Head/Neck, and C-Shape, respectively. Ion chamber measurements were within an average of 0.5% (±1.1%) from the TPS dose. Monte Carlo calculations demonstrated good agreement with the TPS, with a mean 3D-γ passing rate of 98.5% ± 1.9% using a stricter 2%/2-mm criterion. Conclusions: We

  10. Dosimetric Comparison in Breast Radiotherapy of 4 MV and 6 MV on Physical Chest Simulator

    Energy Technology Data Exchange (ETDEWEB)

    Donato da Silva, Sabrina; Passos Ribeiro Campos, Tarcisio [Nuclear Engineering Department, Federal University of Minas Gerais, Belo Horizonte (Brazil); Batista Nogueira, Luciana [Anatomy and Imaging Department, Federal University of Minas Gerais, Belo Horizonte (Brazil); Lima Souza Castro, Andre [Nuclear Engineering Department, Federal University of Minas Gerais, Belo Horizonte (Brazil); Institute of Radiation San Francisco, Belo Horizonte (Brazil); Alves de oliveira, Marcio; Galvao Dias, Humberto [Cancer Hospital in Uberlandia, Uberlandia (Brazil)

    2015-07-01

    According to the World Health Organization (2014) breast cancer is the main cause of death by cancer in women worldwide. The biggest challenge of radiotherapy in the treatment of cancer is to deposit the entire prescribed dose homogeneously in the breast, sparing the surrounding tissue. In this context, this paper aimed at evaluating and comparing internal dose distribution in the mammary gland based on experimental procedures submitted to two distinct energy spectra produced in breast cancer radiotherapy. The methodology consisted of reproducing opposite parallel fields used in the treatment of breast tumors in a chest phantom. This simulator with synthetic breast, composed of equivalent tissue material (TE), was previously developed by the NRI Research Group (UFMG). The computer tomography (CT) scan of the simulator was obtained antecedently. The radiotherapy planning systems (TPS) in the chest phantom were performed in the ECLIPSE system from Varian Medical Systems and CAT 3D system from MEVIS. The irradiations were reproduced in the Varian linear accelerator, model SL- 20 Precise, 6 MV energy and Varian linear accelerator, 4 MV Clinac 6x SN11 model. Calibrations of the absorbed dose versus optical density from radiochromic films were generated in order to obtain experimental dosimetric distribution at the films positioned within the glandular and skin equivalent tissues of the chest phantom. The spatial dose distribution showed equivalence with the TPS on measurement data performed in the 6 MV spectrum. The average dose found in radiochromic films placed on the skin ranged from 49 to 79%, and from 39 to 49% in the mammary areola, for the prescribed dose. Dosimetric comparisons between the spectra of 4 and 6 MV, keeping the constant geometry of the fields applied in the same phantom, will be presented showing their equivalence in breast radiotherapy, as well as the variations will be discussed. To sum up, the dose distribution has reached the value expected in

  11. A dosimetric treatment planning strategy in radioembolization of hepatocarcinoma with 90Y glass microspheres.

    Science.gov (United States)

    Chiesa, C; Mira, M; Maccauro, M; Romito, R; Spreafico, C; Sposito, C; Bhoori, S; Morosi, C; Pellizzari, S; Negri, A; Civelli, E; Lanocita, R; Camerini, T; Bampo, C; Carrara, M; Seregni, E; Marchianò, A; Mazzaferro, V; Bombardieri, E

    2012-12-01

    Our goal was to limit liver toxicity and to obtain good efficacy by developing a dosimetric treatment planning strategy. While several dosimetric evaluations are reported in literature, the main problem of the safety of the treatment is rarely addressed. Our work is the first proposal of a treatment planning method for glass spheres, including both liver toxicity and efficacy issues. Fifty-two patients (series 1) had been treated for intermediated/advanced hepatocellular carcinoma (HCC) with glass spheres, according to the Therasphere® prescription of 120 Gy averaged on the injected lobe. They were retrospectively evaluated with voxel dosimetry, adopting the local deposition hypothesis. Regions of interest on tumor and non tumor parenchyma were drawn to determine the parenchyma absorbed dose, averaged also on non irradiated voxels, excluding tumor voxels. The relationship between the mean non tumoral parenchyma absorbed dose D and observed liver decompensation was analyzed. Basal Child-Pugh strongly affected the toxicity incidence, which was 22% for A5, 57% for A6, 89% for B7 patients. Restricting the analysis to our numerically richest class (basal Child-Pugh A5 patients), D median values were significantly different between toxic (median 90 Gy) and non toxic treatments (median 58 Gy) at a Mann-Withney test, (P=0.033). Using D as a marker for toxicity, the separation of the two populations in terms of area under ROC curve was 0.75, with 95% C.I. of [0.55-0.95]. The experimental Normal Tissue Complication Probability (NTCP) curve as a function of D resulted in the following values: 0%, 14%, 40%, 67% for D interval of [0-35] Gy, [35-70] Gy, [70-105] Gy, [105-140] Gy. A limit of about 70 Gy for the mean absorbed dose to parenchyma was assumed for A5 patients, corresponding to a 14% risk of liver decompensation. This result is applicable only to our administration conditions: glass spheres after a decay interval of 3.75 days. Different safety limit (40 Gy) are

  12. Changes in the Extracellular Matrix Are Associated With the Development of Serous Tubal Intraepithelial Carcinoma Into High-Grade Serous Carcinoma.

    Science.gov (United States)

    van der Steen, Sophieke C H A; Bulten, Johan; Van de Vijver, Koen K; van Kuppevelt, Toin H; Massuger, Leon F A G

    2017-07-01

    The identification of a marker for early progression of preinvasive lesions into invasive pelvic high-grade serous carcinoma (HGSC) may provide novel handles for innovative screening and prevention strategies. The interplay between cancer cells and the extracellular matrix (ECM) is one of the main principles in cancer development and growth, but has been largely neglected in preinvasive lesions. This is the first study addressing the involvement of the ECM in the "step-by-step" transition of normal fallopian tube epithelium into preinvasive lesions, and eventually the progression of preinvasive lesions into invasive HGSC. The expression of highly sulfated chondroitin sulfate (CS-E), a characteristic glycosaminoglycan of the cancer-associated ECM, was assessed by immunohistochemistry in a large cohort of precursor lesions of the full spectrum of HGSC development, including 97 serous tubal intraepithelial carcinomas (STICs), 27 serous tubal intraepithelial lesions, and 24 p53 signatures. In addition, the immunological reactivity in the microenvironment was evaluated. Increased stromal expression of highly sulfated CS-E was observed in 3.7%, 57.7%, and 90.6% of serous tubal intraepithelial lesions, STICs, and invasive HGSCs, respectively (P STIC, P STIC and paired HGSC was demonstrated. Intense stromal CS-E expression in STIC was significantly associated with an immune infiltrate (P < 0.001). Our study showed that increased stromal CS-E expression is related to the degree of the tubal epithelium abnormality. Specific alterations in the ECM (ie, CS-E expression) occur early in pelvic HGSC development and may represent a novel biomarker of early cancer progression, useful for the identification of novel clinical strategies.

  13. Development of reading and phonological skills of children at family risk for dyslexia: a longitudinal analysis from kindergarten to sixth grade.

    Science.gov (United States)

    Dandache, Sophie; Wouters, Jan; Ghesquière, Pol

    2014-11-01

    The main focus of this article is to develop a better understanding of the developmental trajectories of literacy and phonological skills within Dutch-speaking children. Children at high and low risk for dyslexia were followed and compared at four different moments: kindergarten and first, third and sixth grades. Three groups were then compared: (1) dyslexic readers; (2) normal readers at high risk for dyslexia; and (3) normal readers at low risk for dyslexia. Children diagnosed with dyslexia scored lower than high-risk normal readers on phonological awareness (PA), rapid automatized naming (RAN), verbal short-term memory and literacy skills. Normal readers at high risk scored between both groups, confirming that dyslexia is to be considered as a continuum rather than an all-or-none condition. Growth analyses showed that the three groups evolved similarly on all measures except for phoneme deletion and literacy measures. Finally, solely PA and RAN explained a significant amount of variance in the evolution of reading skills. Copyright © 2014 John Wiley & Sons, Ltd.

  14. Developmental changes in reading do not alter the development of visual processing skills: An application of explanatory item response models in grades K-2

    Directory of Open Access Journals (Sweden)

    Kristi L Santi

    2015-02-01

    Full Text Available Visual processing has been widely studied in regard to its impact on a students’ ability to read. A less researched area is the role of reading in the development of visual processing skills. A cohort-sequential, accelerated-longitudinal design was utilized with 932 kindergarten, first, and second grade students to examine the impact of reading acquisition on the processing of various types of visual discrimination and visual motor test items. Students were assessed four times per year on a variety of reading measures and reading precursors and two popular measures of visual processing over a three-year period. Explanatory item response models were used to examine the roles of person and item characteristics on changes in visual processing abilities and changes in item difficulties over time. Results showed different developmental patterns for five types of visual processing test items, but most importantly failed to show consistent effects of learning to read on changes in item difficulty. Thus, the present study failed to find support for the hypothesis that learning to read alters performance on measures of visual processing. Rather, visual processing and reading ability improved together over time with no evidence to suggest cross-domain influences from reading to visual processing. Results are discussed in the context of developmental theories of visual processing and brain-based research on the role of visual skills in learning to read.

  15. Developing novel one-step processes for obtaining food-grade O/W emulsions from pressurized fluid extracts: processes description, state of the art and perspectives

    Directory of Open Access Journals (Sweden)

    Diego Tresinari SANTOS

    2015-01-01

    Full Text Available AbstractIn this work, a novel on-line process for production of food-grade emulsions containing oily extracts, i.e. oil-in-water (O/W emulsions, in only one step is presented. This process has been called ESFE, Emulsions from Supercritical Fluid Extraction. With this process, emulsions containing supercritical fluid extracts can be obtained directly from plant materials. The aim in the conception of this process is to propose a new rapid way to obtain emulsions from supercritical fluid extracts. Nowadays the conventional emulsion formulation method is a two-step procedure, i.e. first supercritical fluid extraction for obtaining an extract; secondly emulsion formulation using another device. Other variation of the process was tested and successfully validated originating a new acronymed process: EPFE (Emulsions from Pressurized Fluid Extractions. Both processes exploit the supercritical CO2-essential oils miscibility, in addition, EPFE process exploits the emulsification properties of saponin-rich pressurized aqueous plant extracts. The feasibility of this latter process was demonstrated using Pfaffia glomerata roots as source of saponin-rich extract, water as extracting solvent and clove essential oil, directly extracted using supercritical CO2, as a model dispersed phase. In addition, examples of pressurized fluid-based coupled processes applied for adding value to food bioactive compounds developed in the past five years are reviewed.

  16. O desenvolvimento do texto dissertativo em crianças da 4ª série The development of argumentative text by fourth grade children

    Directory of Open Access Journals (Sweden)

    Sérgio Antonio da Silva Leite

    2000-03-01

    Full Text Available Esta pesquisa analisa o desenvolvimento da habilidade de produzir textos dissertativos em crianças da 4ª. série, relacionando com o contexto em que foram produzidos. Este estudo justifica-se devido à escassez de trabalhos lingüísticos na área, bem como ao alto índice de fracasso dos alunos nesta modalidade de texto. Coletou-se a produção escrita de crianças de rede pública, durante um período de três meses. O material foi analisado buscando-se identificar os operadores argumentativos, os tipos de argumentos utilizados e o estágio da capacidade argumentativa dessas crianças. O estudo sugere que a introdução do texto argumentativo nas séries iniciais do 1º grau, além de proporcionar mais chances de sucesso aos alunos na produção deste tipo de texto ao término do 2º grau, certamente facilitará o desenvolvimento de uma postura crítica, possibilitando aos alunos refletirem sobre a realidade social onde vivem.This reaserch analysed the developmental stage of fourth grade (primary school children in ability of writting argumentative texts joint with their context. The reason of this reaserch is the lack of new studies in linguistical area and high ratio of unable students to make this kind of text. It will be showed the analysis of making text by public schools children for three months. These data were analysed trying identify argumentative operators, the kinds of arguments used and the stage of the argumentative ability of these children. The study showed that the introduction of argumentative text in first grades give them more chances of succeed, preparing these pupils in their finishing high school. This fact obviously will make easier the development of their critical point of view, helping the students to think about their living social reality.

  17. Developing and Evaluating an Eighth Grade Curriculum Unit That Links Foundational Chemistry to Biological Growth: Designing Professional Development to Support Teaching

    Science.gov (United States)

    Kruse, Rebecca; Howes, Elaine V.; Carlson, Janet; Roth, Kathleen; Bourdelat-Parks, Brooke

    2013-01-01

    AAAS and BSCS are collaborating to develop and study a curriculum unit that supports students' ability to explain a variety of biological processes such as growth in chemical terms. The unit provides conceptual coherence between chemical processes in nonliving and living systems through the core idea of atom rearrangement and conservation during…

  18. Organ motion study and dosimetric impact of respiratory gating radiotherapy for esophageal cancer

    International Nuclear Information System (INIS)

    Lorchel, F.

    2007-04-01

    Chemoradiotherapy is now the standard treatment for locally advanced or inoperable esophageal carcinoma. In this indication, conformal radiotherapy is generally used. However, prognosis remains poor for these patients. Respiratory gating radiotherapy can decrease healthy tissues irradiation and allows escalation dose in lung, liver and breast cancer. In order to improve radiotherapy technique, we propose to study the feasibility of respiratory gating for esophageal cancer. We will study the respiratory motions of esophageal cancer to optimize target volume delineation, especially the internal margin (I.M.). We will test the correlation between tumour and chest wall displacements to prove that esophageal cancer motions are induced by respiration. This is essential before using free breathing respiratory gating systems. We will work out the dosimetric impact of respiratory gating using various dosimetric analysis parameters. We will compare dosimetric plans at end expiration, end inspiration and deep inspiration with dosimetric plan in free-breathing condition. This will allow us to establish the best respiratory phase to irradiate for each gating system. This dosimetric study will be completed with linear quadratic equivalent uniform dose (E.U.D.) calculation for each volume of interest. Previously, we will do a theoretical study of histogram dose volume gradation to point up its use. (author)

  19. Study of dosimetric systems-ferrous sulfate-ferric sulfate, glass slides and dyed aqueous solutions

    International Nuclear Information System (INIS)

    Fernandes, L.

    1979-01-01

    The effect of some variables which can effect the preparation of the ferrous sulfate used as dosimetric solution has been studied. Among these variables the purity of the water used for the preparation of the solution and the presence (or absence) of oxygen in the dosimetric solution were considered. The dose rate distribution according to the transverse and longitudinal sections of the Co 60 irradiator was studied experimentally, using the dosimetric solution, and theoretically, using a computer program (KIFE). The results obtained with the ferrous sulface dosimetric solution were used as reference for the study of the application of EM and MSG glass slide as a dosimetric system. For this purpose the effects of the weakening of the coloration induced in the glass by gamma rays (Co 60 ) and the relationship between the absorbed dose of radiation and the ratio between the variation in absorbation value and the thickness of the glass irradiated, were studied. A study was also made of the use of the dye indicators bromothymol-blue, methyl-orange, Congo-red, neutral-red and p-nitrophenol, in aqueous solution, for radiation dose measurements. The bleaching of each indicator solution, under gamma-radiation (Co 60 ) was studied in oxygen and nitrogen atmospheres.(Author) [pt

  20. The Effectiveness of Using Linguistic Classroom Activities in Teaching English Language in Developing the Skills of Oral Linguistic Performance and Decision Making Skill among Third Grade Intermediate Students in Makah

    Science.gov (United States)

    Alshareef, Fahd Majed

    2016-01-01

    The study aimed to reveal the effectiveness of the use of certain classroom language activities in teaching English language in the development of oral linguistic performance and decision-making among intermediate third-grade students in Makah, and it revealed a statistically significant correlation relationship between the averages of the study…

  1. A Case Study on Specialised Content Knowledge Development with Dynamic Geometry Software: The Analysis of Influential Factors and Technology Beliefs of Three Pre-Service Middle Grades Mathematics Teachers

    Science.gov (United States)

    Zambak, Vecihi S.; Tyminski, Andrew M.

    2017-01-01

    This study characterises the development of Specialised Content Knowledge (SCK) with dynamic geometry software (DGS) throughout a semester. The research employed a single-case study with the embedded units of three pre-service middle grades mathematics teachers. Qualitative data were collected, and factors affecting these three teachers' SCK…

  2. Teaching Explicitly and Reflecting on Elements of Nature of Science: a Discourse-Focused Professional Development Program with Four Fifth-Grade Teachers

    Science.gov (United States)

    Piliouras, Panagiotis; Plakitsi, Katerina; Seroglou, Fanny; Papantoniou, Georgia

    2017-06-01

    The nature of science (NOS) has become a central goal of science education in many countries. This study refers to a developmental work research program, in which four fifth-grade elementary in-service teachers participated. It aimed to improve their understandings of NOS and their abilities to teach it effectively to their students. The 1-year-long, 2012-2013, program consisted of a series of activities to support teachers to develop their pedagogical content knowledge of NOS. In order to accomplish our goal, we enabled teacher-researchers to analyze their own discourse practices and to trace evidence of effective NOS teaching. Many studies indicate the importance of examining teachers' discussions about science in the classroom, since it is teachers' understanding of NOS reflected in these discussions that will have a vital impact on students' learning. Our proposal is based on the assumption that reflecting on the ways people form meanings enables us to examine and seek alternative ways to communicate aspects of NOS during science lessons. The analysis of discourse data, which has been carried out with the teacher-researchers' active participation, indicated that initially only a few aspects of NOS were implicitly incorporated in teacher-researchers' instruction. As the program evolved, all teacher-researchers presented more informed views on targeted NOS aspects. On the whole, our discourse-focused professional development program with its participatory, explicit, and reflective character indicated the importance of involving teacher-researchers in analyzing their own talk. It is this involvement that results in obtaining a valuable awareness of aspects concerning pedagogical content knowledge of NOS teaching.

  3. Developing Grades 1-6 Teachers’ English Communication Skills and English Teaching Techniques Using Training and Coaching in Lop Buri Thailand

    Directory of Open Access Journals (Sweden)

    Kanya Kongsoongnoen

    2017-10-01

    Full Text Available The purposes of this research were (1 to develop English for communication skills for grades 1-6 teachers, 2 to develop the teachers’ English teaching skills, and (3 to increase the students’ English Achievement.  The participants were 15 teachers with no degree in English from 14 small size primary schools in Lop Buri province Thailand. The 30 hour English communication and 30 hour English teaching training were provided to the teachers. School visits with Coaching approach were applied for supporting their teaching at schools as well as teaching materials the teachers needed. A questionnaire comprising both open and closed-ended questions was used to evaluate the teachers’ teaching. The interview questions and the teachers’ reflection form were conducted for collecting their perception on the project, percentage and mean were applied to analyze quantitative data whereas content analysis was conducted for qualitative data. The findings showed that the teachers’ English for communication skills and English teaching skills were increased. The teachers’ English communication skills and their teaching skills were higher than before whereas their teaching application was at a medium level. Fifty percent of the teachers’ teaching skills were at a high level while 20% barely applied their teaching experience they received from the training and coaches. One hundred percent of the teachers agreed that the project was the most useful for them and many highlighted that they’d immensely learned teaching techniques and just realized that they could make their English class interesting for the students because they felt confident after the training. However, a few teachers had no chance to teach English because their schools had someone qualified to teach instead.

  4. Dosimetric and biological assessment in the Cuban program for children from areas affected by the Chernobyl accidents

    International Nuclear Information System (INIS)

    Garcia Lima, O.; Cruz, R.; Valdez, M.; Cardenas, J.; Jova, L.; Lopez, G.; Arado, O.; Lamadrid, A.I.; Morera, L.

    1996-01-01

    Since 1990 Cuba has been developing health care program to offer highly specialized medical assistance and to develop a rehabilitation program for children affected by the Chernobyl accident. as part of the program a group of dosimetric and biomedical studies have been performed tom asses the impact of the accident. The results obtained from the study with 4500 children streets the fact that external radiation was the most important contributor to the total dose, which was estimated between 1-170 mSv during 70 years, for an equal period of time the 137C s internal dose ranged between 1.5 and 565 Bq/Kg. The biomedical studies have been carried out in groups formed according to the surface contamination of the field and to the 137C s activity measured, The thyroid hyperplasia tend to increase with the increment of both parameters. The other analyzed factors did not show differences among the groups

  5. Study of national dosimetric standards for external beam radiotherapy: application to conformal irradiations

    International Nuclear Information System (INIS)

    Le Roy, M.

    2011-01-01

    The development of new treatment modalities such as IMRT and stereotactic radiotherapy has led to an increasing use of complex fields composed of small beams with multiple incidence angles. These new treatment conditions are very far from classical reference conditions on which international dosimetry protocols are based. In this work, we propose to realize dosimetric standards for radiation fields smaller than the standard 10 * 10 cm 2 field, namely 4 * 4 and 2 * 2 cm 2 . The calibration coefficients of an ionization chamber in terms of absorbed dose to water for these radiation fields were compared in the 6 MV (with and without flattening filter) and 12 MV beams of LNHB medical linac. The references were established from a graphite calorimetry measurement. A graphite calorimeter of small sensitive volume was built specifically for the 2 * 2 cm 2 field. In addition, an ionization chamber suitable to this field size was looked for. We showed that, for the studied beams, the reference chamber's calibration coefficient is independent of the radiation field size between 10 * 10 and 2 * 2 cm 2 , within uncertainties (about 0.4 % at one standard deviation). (author) [fr

  6. A custom made phantom for dosimetric audit and quality assurance of three-dimensional conformal radiotherapy

    International Nuclear Information System (INIS)

    Radaideh, K.M.; Matalqah, L.M.; Matalqah, L.M.; Tajuddin, A.A.; Luen, F.W.L.; Bauk, S.; Abdel Munem, E.M.E.

    2012-01-01

    The ultimate check of the actual dose delivered to a patient in radiotherapy can be achieved by using dosimetric measurements. The aims of this study were to develop and evaluate a custom handmade head and neck phantom for evaluation of Three-Dimensional Conformal Radiation Therapy (3D-CRT) dose planning and delivery. A phantom of head and neck region of a medium built male patient with nasopharyngeal cancer was constructed from Perspex material. Primary and secondary Planning Target Volume (PTV) and twelve Organs at Risk (OAR) were delineated using Treatment Planning System (TPS) guided by computed tomography printout transverse images. One hundred and seven (107) holes distributed among the organs were loaded with Rod-shaped Thermoluminescent dosimeters (LiF:Mg, Ti TLDs) after common and individual calibration. Head and neck phantom was imaged, planned and irradiated conformally (3D-CRT) by linear accelerator (LINAC Siemens Artiste). The planned predicted doses by TPS at PTV and OAR regions were obtained and compared with the TLD measured doses using the phantom. Repeated TLD measurements were reproducible with a percent standard deviation of < 3.5 %. Moreover, the average of dose discrepancies between TLDs reading and TPS predicted doses were found to be < 5.3 %. The phantom's preliminary results have proved to be a valuable tool for 3D-CRT treatment dose verification. (author)

  7. FLUKA Monte Carlo for Basic Dosimetric Studies of Dual Energy Medical Linear Accelerator

    Directory of Open Access Journals (Sweden)

    K. Abdul Haneefa

    2014-01-01

    Full Text Available General purpose Monte Carlo code for simulation of particle transport is used to study the basic dosimetric parameters like percentage depth dose and dose profiles and compared with the experimental measurements from commercial dual energy medical linear accelerator. Varian Clinac iX medical linear accelerator with dual energy photon beams (6 and 15 MV is simulated using FLUKA. FLAIR is used to visualize and edit the geometry. Experimental measurements are taken for 100 cm source-to-surface (SSD in 50 × 50 × 50 cm3 PTW water phantom using 0.12 cc cylindrical ionization chamber. Percentage depth dose for standard square field sizes and dose profiles for various depths are studied in detail. The analysis was carried out using ROOT (a DATA analysis frame work developed at CERN system. Simulation result shows good agreement in percentage depth dose and beam profiles with the experimental measurements for Varian Clinac iX dual energy medical linear accelerator.

  8. Simulation and dosimetric analysis of proton and carbon ion therapy in the treatment of uveal melanoma

    Energy Technology Data Exchange (ETDEWEB)

    Christovao, Marilia Tavares, E-mail: marilia@cdtn.br [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil); Campos, Tarcisio Passos Ribeiro de; Trindade, Bruno Machado [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Dept. de Engenharia Nuclear

    2011-11-15

    The present paper addresses the dosimetric evaluation of carbon ion radiotherapy as compared with proton therapy. Materials and methods: computer simulations were undertaken with the Geant4 (GEometry ANd Tracking) code. An eye model discretized into voxels and implemented in the Siscodes system (computer system for dosimetry in radiation therapy) was utilized to generate and superimpose depth dose profiles and isodose curves. Different values for beam energy were adopted in the simulations of carbon ion beams, while in the simulation with proton beams irradiation line devices were included with different absorbing material thicknesses. Results: the simulations outputs were processed and integrated into the Siscodes to generate the spatial dose distribution in the eye model, considering changes in the beam entrance position. The dose rates were normalized as a function of the maximum dose for a beam at a specific entrance position, incident particle energy and number of incident carbon ions and protons. Conclusion: the described benefits together with the presented results contribute to the development of clinical applications and researches on carbon ion and proton therapy. (author)

  9. Dosimetric evaluation of anti-CD20 labelled with 188Re

    International Nuclear Information System (INIS)

    Barrio, Graciela; Osso Junior, Joao A.

    2011-01-01

    Radioimmunotherapy has the potential to deliver lethal radiation energy directly to malignant cells via targeting of radioisotope-conjugated monoclonal antibodies (MAbs) to specific antigens. B-cell lymphoma is a particularly good candidate for radioimmunotherapy because the disease is inherently radiosensitive, malignant cells in the blood, bone marrow, spleen and lymphonodes are accessible, and MAbs have been developed to B-cell surface antigens that do not shed or modulate. Rituximab (RTX), the human IgG1-type chimeric form of the parent murine antibody ibritumomab, is specifically targeted against CD20, a surface antigen expressed by pre-B and mature human B lymphocytes. The use of rhenium-188 from a 188 W/ 188 Re generator system represents an attractive alternative radionuclide for therapy. 188 Re is produced from beta decay of the 188 W parent. In addition to the emission of high-energy electrons (Eβ= 2118 keV), 188 Re also decays with emission of a gamma photon with an energy of 155 keV in 15% abundance. Besides the therapeutic usefulness of 188 Re, the emission of gamma photon is an added advantage since the biodistribution of 188 Re-labeled antibodies can be evaluated in vivo with a gamma camera. Also, rhenium has chemical properties similar to technetium. Thus, both can be conjugated to antibodies using similar chemistry methods. The objective of this work is to prove the usefulness of this radiopharmaceutical based on dosimetric studies, that are also required by the Brazilian Regulatory Agency (ANVISA). (author)

  10. Dosimetric benefit of adaptive re-planning in pancreatic cancer stereotactic body radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Li, Yongbao [Department of Engineering Physics, Tsinghua University, Key Laboratory of Particle & Radiation Imaging (Tsinghua University), Ministry of Education, Beijing (China); Center for Advanced Radiotherapy Technologies University of California San Diego, La Jolla, CA (United States); Department of Radiation Oncology, University of California San Diego, La Jolla, CA (United States); Department of Radiation Oncology, University of Texas Southwestern Medical Center, Dallas, TX (United States); Hoisak, Jeremy D.P.; Li, Nan; Jiang, Carrie [Center for Advanced Radiotherapy Technologies University of California San Diego, La Jolla, CA (United States); Department of Radiation Oncology, University of California San Diego, La Jolla, CA (United States); Tian, Zhen [Center for Advanced Radiotherapy Technologies University of California San Diego, La Jolla, CA (United States); Department of Radiation Oncology, University of California San Diego, La Jolla, CA (United States); Department of Radiation Oncology, University of Texas Southwestern Medical Center, Dallas, TX (United States); Gautier, Quentin; Zarepisheh, Masoud [Center for Advanced Radiotherapy Technologies University of California San Diego, La Jolla, CA (United States); Department of Radiation Oncology, University of California San Diego, La Jolla, CA (United States); Wu, Zhaoxia; Liu, Yaqiang [Department of Engineering Physics, Tsinghua University, Key Laboratory of Particle & Radiation Imaging (Tsinghua University), Ministry of Education, Beijing (China); Jia, Xun [Center for Advanced Radiotherapy Technologies University of California San Diego, La Jolla, CA (United States); Department of Radiation Oncology, University of California San Diego, La Jolla, CA (United States); Department of Radiation Oncology, University of Texas Southwestern Medical Center, Dallas, TX (United States); and others

    2015-01-01

    Stereotactic body radiotherapy (SBRT) shows promise in unresectable pancreatic cancer, though this treatment modality has high rates of normal tissue toxicity. This study explores the dosimetric utility of daily adaptive re-planning with pancreas SBRT. We used a previously developed supercomputing online re-planning environment (SCORE) to re-plan 10 patients with pancreas SBRT. Tumor and normal tissue contours were deformed from treatment planning computed tomographies (CTs) and transferred to daily cone-beam CT (CBCT) scans before re-optimizing each daily treatment plan. We compared the intended radiation dose, the actual radiation dose, and the optimized radiation dose for the pancreas tumor planning target volume (PTV) and the duodenum. Treatment re-optimization improved coverage of the PTV and reduced dose to the duodenum. Within the PTV, the actual hot spot (volume receiving 110% of the prescription dose) decreased from 4.5% to 0.5% after daily adaptive re-planning. Within the duodenum, the volume receiving the prescription dose decreased from 0.9% to 0.3% after re-planning. It is noteworthy that variation in the amount of air within a patient's stomach substantially changed dose to the PTV. Adaptive re-planning with pancreas SBRT has the ability to improve dose to the tumor and decrease dose to the nearby duodenum, thereby reducing the risk of toxicity.

  11. Calculation of Hazard Category 2/3 Threshold Quantities Using Contemporary Dosimetric Data

    Energy Technology Data Exchange (ETDEWEB)

    Walker, William C. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2017-11-01

    The purpose of this report is to describe the methodology and selection of input data utilized to calculate updated Hazard Category 2 and Hazard Category 3 Threshold Quantities (TQs) using contemporary dosimetric information. The calculation of the updated TQs will be considered for use in the revision to the Department of Energy (DOE) Technical Standard (STD-) 1027-92 Change Notice (CN)-1, “Hazard Categorization and Accident Analysis Techniques for Compliance with DOE Order 5480.23, Nuclear Safety Analysis Reports.” The updated TQs documented in this report complement an effort previously undertaken by the National Nuclear Security Administration (NNSA), which in 2014 issued revised Supplemental Guidance documenting the calculation of updated TQs for approximately 100 radionuclides listed in DOE-STD-1027-92, CN-1. The calculations documented in this report complement the NNSA effort by expanding the set of radionuclides to more than 1,250 radionuclides with a published TQ. The development of this report was sponsored by the Department of Energy’s Office of Nuclear Safety (AU-30) within the Associate Under Secretary for Environment, Health, Safety, and Security organization.

  12. The development of learning competency and skills for the 21st century to integrate "TPCK" of world life with local environment in students grade 11

    Science.gov (United States)

    Jedaman, Pornchai; Kinboon, Nittayaporn; Suksup, Chareon; Kinboon, Wutcharapong

    2018-01-01

    The teaching strategies of append were the technological pedagogical content knowledge; TPCK. This description knowledge in a content to corresponds of a effective teaching. This article aims to address the relevance of; 1) the learning competency and skills for the 21st Century to integrate "TPCK" of a world life with local environment in the students grade 11, 2) the effective achievement of the learning competency and skills to integrate "TPCK" of world life with local environment in the students grade 11 were the passing score of a percentage 80 upwards (EI.), and 3) the attitudes for learning activities in the students grade 11. The study employed both quantitative and qualitative approaches for 9teachers of third schools were the participatory action research (PAR) in collecting data including a instructional, a testing, and a questionnaire surveywith 33 students grade 11 of Phuwiengwittayakom school. The participants werecluster random sampling. The data analysis of descriptive statistical, percentage, mean average, standard deviation. The findings in the study were to learning competency and skills for the 21st Century to integrate "TPCK" of a world life with local environment on TK, PK, CK, and TCK at a excellent levels (X¯ = 3.62, 3.57, 3.54, 3.51) respectively, and PCK, TPK,TPCK at a good levels (X¯ = 3.36, 3.23, 3.17) respectively. The effective achievement of the learning competency and skills to integrate "TPCK" of world life with local environment in 30 students grade 11 were the passing score (EI.) of a percentage at 90.91. The attitudes for learning activities in the students grade 11 at a high levels (X¯ =3.29). In addition of the students grade 11 to understanding of the importance were a local learning resources including the value integrating technology of the knowledge technology and to choose the right were create of an effective information.

  13. Dosimetric aspects of radiation processing of food and allied products

    International Nuclear Information System (INIS)

    Sharma, G.; Bhat, R.M.; Bhatt, B.C.

    2010-01-01

    Full text: Gamma radiation processing in the last 4-5 decades is continuously gaining importance in processing of a wide variety of products, as it can modify physical, chemical and biological properties of the materials, including food and allied products on industrial scale due its inherent qualities like ease of processing in finally packaged form, eco-friendly nature and other obvious reasons over conventional means of processing. Food and allied products are either from agricultural produce or animal origin; they get easily contaminated from soil during harvesting, handling, processing, environment conditions, storage and transport from various types of micro-organisms including pathogens. In many countries it is mandatory to bring down the population of micro-organisms to an acceptable level and complete elimination of pathogens before such products are accepted for human or animal consumption. Processing of food and allied products by radiation has its own challenges due to wider public acceptance of irradiated food, a wide range, 0.25-50kGy, of absorbed dose requirements for different category of such products and purposes, use of a variety of packaging materials in different shapes and sizes and because of its perishable nature. More than 50 countries including India in the world have accepted radiation processing of food and allied products by radiation. Dosimetry is an important aspect of radiation processing, whether it is food or allied product. Uniformity in dose delivered to these products depends on several factors such as product carrier to source frame alignment, product carrier and product/tote box design, product loading pattern, attenuation due to product thickness, product bulk density that varies from 0.1-1.0 kg/l and the plant design whether during processing product overlaps the source or otherwise. In this presentation dosimetric aspects of radiation processing of food and allied products and problems associated with dosimetry of such

  14. Neo-adjuvant chemo-radiation of rectal cancer with Volumetric Modulated Arc Therapy: summary of technical and dosimetric features and early clinical experience

    International Nuclear Information System (INIS)

    Richetti, Antonella; Fogliata, Antonella; Clivio, Alessandro; Nicolini, Giorgia; Pesce, Gianfranco; Salati, Emanuela; Vanetti, Eugenio; Cozzi, Luca

    2010-01-01

    To report about initial technical and clinical experience in preoperative radiation treatment of rectal cancer with volumetric modulated arcs with the RapidArc ® (RA) technology. Twenty-five consecutive patients (pts) were treated with RA. All showed locally advanced rectal adenocarcinoma with stage T2-T4, N0-1. Dose prescription was 44 Gy in 22 fractions (or 45 Gy in 25 fractions). Delivery was performed with single arc with a 6 MV photon beam. Twenty patients were treated preoperatively, five did not receive surgery. Twenty-three patients received concomitant chemotherapy with oral capecitabine. A comparison with a cohort of twenty patients with similar characteristics treated with conformal therapy (3DC) is presented as well. From a dosimetric point of view, RA improved conformality of doses (CI 95% = 1.1 vs. 1.4 for RA and 3DC), presented similar target coverage with lower maximum doses, significant sparing of femurs and significant reduction of integral and mean dose to healthy tissue. From the clinical point of view, surgical reports resulted in a down-staging in 41% of cases. Acute toxicity was limited to Grade 1-2 diarrhoea in 40% and Grade 3 in 8% of RA pts, 45% and 5% of 3DC pts, compatible with known effects of concomitant chemotherapy. RA treatments were performed with an average of 2.0 vs. 3.4 min of 3DC. RA proved to be a safe, qualitatively advantageous treatment modality for rectal cancer, showing some improved results in dosimetric aspects

  15. Neo-adjuvant chemo-radiation of rectal cancer with Volumetric Modulated Arc Therapy: summary of technical and dosimetric features and early clinical experience

    Directory of Open Access Journals (Sweden)

    Salati Emanuela

    2010-02-01

    Full Text Available Abstract Background To report about initial technical and clinical experience in preoperative radiation treatment of rectal cancer with volumetric modulated arcs with the RapidArc® (RA technology. Methods Twenty-five consecutive patients (pts were treated with RA. All showed locally advanced rectal adenocarcinoma with stage T2-T4, N0-1. Dose prescription was 44 Gy in 22 fractions (or 45 Gy in 25 fractions. Delivery was performed with single arc with a 6 MV photon beam. Twenty patients were treated preoperatively, five did not receive surgery. Twenty-three patients received concomitant chemotherapy with oral capecitabine. A comparison with a cohort of twenty patients with similar characteristics treated with conformal therapy (3DC is presented as well. Results From a dosimetric point of view, RA improved conformality of doses (CI95% = 1.1 vs. 1.4 for RA and 3DC, presented similar target coverage with lower maximum doses, significant sparing of femurs and significant reduction of integral and mean dose to healthy tissue. From the clinical point of view, surgical reports resulted in a down-staging in 41% of cases. Acute toxicity was limited to Grade 1-2 diarrhoea in 40% and Grade 3 in 8% of RA pts, 45% and 5% of 3DC pts, compatible with known effects of concomitant chemotherapy. RA treatments were performed with an average of 2.0 vs. 3.4 min of 3DC. Conclusion RA proved to be a safe, qualitatively advantageous treatment modality for rectal cancer, showing some improved results in dosimetric aspects.

  16. Dosimetric response of united, commercially available CTA foils for sup 6 sup 0 Co gamma rays

    CERN Document Server

    Peimel-Stuglik, Z

    2001-01-01

    The usefulness of two kinds of untinted CTA foils: Fuji CTR-125 dosimetric foil and technical CTA-T foil, produced by 'Zaklady Chemiczne, 'Gorzow Wielkopolski' as support for light-sensitive layers of amateur photo-films, for sup 6 sup 0 Co gamma ray dosimetry was investigated. In spite of rather bad physical parameters of the technical foil (spread of foil thickness, high and different initial absorbance) the dosimetric response of both foils for sup 6 sup 0 Co gamma rays was similar. The CTA-T foil can be used for routine dosimetry providing that dosimetric signals have to be calculated exactly as recommended by the ASTM (American Society for Testing and Materials) standard, i.e. as the difference of absorbance of irradiated and (the same) non-irradiated foil. Any other approach may lead to high errors of dose evaluation. The last is true also for other CTA foils, especially after long self-life.

  17. Transport and dosimetric solutions for the ELIMED laser-driven beam line

    International Nuclear Information System (INIS)

    Cirrone, G.A.P.; Romano, F.; Scuderi, V.; Amato, A.; Candiano, G.; Cuttone, G.; Giove, D.; Korn, G.; Krasa, J.; Leanza, R.; Manna, R.; Maggiore, M.; Marchese, V.; Margarone, D.; Milluzzo, G.; Petringa, G.; Sabini, M.G.; Schillaci, F.

    2015-01-01

    Within 2017, the ELIMED (ELI-Beamlines MEDical applications) transport beam-line and dosimetric systems for laser-generated beams will be installed at the ELI-Beamlines facility in Prague (CZ), inside the ELIMAIA (ELI Multidisciplinary Applications of laser–Ion Acceleration) interaction room. The beam-line will be composed of two sections: one in vacuum, devoted to the collecting, focusing and energy selection of the primary beam and the second in air, where the ELIMED beam-line dosimetric devices will be located. This paper briefly describes the transport solutions that will be adopted together with the main dosimetric approaches. In particular, the description of an innovative Faraday Cup detector with its preliminary experimental tests will be reported

  18. Dosimetric evaluation of an automatic segmentation tool of pelvic structures from MRI images for prostate cancer radiotherapy; Evaluation dosimetrique d'un outil de delineation automatique des organes pelviens a partir d'images IRM pour la radiotherapie du cancer prostatique

    Energy Technology Data Exchange (ETDEWEB)

    Pasquier, D.; Lacornerie, T.; Lartigau, E. [Centre Oscar-Lambret, Dept. Universitaire de Radiotherapie, 59 - Lille (France); Pasquier, D. [Centre Galilee, Polyclinique de la Louviere, 59 - Lille (France); Pasquier, D.; Betrouni, N.; Vermandel, M.; Rousseau, J. [Lille-2 Univ., U703 Thiais, Inserm, Lab. de Biophysique EA 1049, Institut de Technologie Medicale, CHU de Lille, 59 (France)

    2008-09-15