WorldWideScience

Sample records for maximal dose modification

  1. Objective method to report planner-independent skin/rib maximal dose in balloon-based high dose rate (HDR) brachytherapy for breast cancer

    International Nuclear Information System (INIS)

    Kim, Yongbok; Trombetta, Mark G.

    2011-01-01

    Purpose: An objective method was proposed and compared with a manual selection method to determine planner-independent skin and rib maximal dose in balloon-based high dose rate (HDR) brachytherapy planning. Methods: The maximal dose to skin and rib was objectively extracted from a dose volume histogram (DVH) of skin and rib volumes. A virtual skin volume was produced by expanding the skin surface in three dimensions (3D) external to the breast with a certain thickness in the planning computed tomography (CT) images. Therefore, the maximal dose to this volume occurs on the skin surface the same with a conventional manual selection method. The rib was also delineated in the planning CT images and its maximal dose was extracted from its DVH. The absolute (Abdiff=|D max Man -D max DVH |) and relative (Rediff[%]=100x(|D max Man -D max DVH |)/D max DVH ) maximal skin and rib dose differences between the manual selection method (D max Man ) and the objective method (D max DVH ) were measured for 50 balloon-based HDR (25 MammoSite and 25 Contura) patients. Results: The average±standard deviation of maximal dose difference was 1.67%±1.69% of the prescribed dose (PD). No statistical difference was observed between MammoSite and Contura patients for both Abdiff and Rediff[%] values. However, a statistically significant difference (p value max >90%) compared with lower dose range (D max <90%): 2.16%±1.93% vs 1.19%±1.25% with p value of 0.0049. However, the Rediff[%] analysis eliminated the inverse square factor and there was no statistically significant difference (p value=0.8931) between high and low dose ranges. Conclusions: The objective method using volumetric information of skin and rib can determine the planner-independent maximal dose compared with the manual selection method. However, the difference was <2% of PD, on average, if appropriate attention is paid to selecting a manual dose point in 3D planning CT images.

  2. The guinea pig maximization test--with a multiple dose design

    DEFF Research Database (Denmark)

    Andersen, Klaus Ejner; Vølund, A; Frankild, S

    1995-01-01

    The guinea pig maximization test (GPMT) is usually performed with one moderately irritant induction dose of the allergen and gives a qualitative assessment-hazard identification-of the allergenicity of the chemical. We refined the GPMT by applying a multiple dose design and used 30 guinea pigs in...

  3. The guinea pig maximization test--with a multiple dose design

    DEFF Research Database (Denmark)

    Andersen, Klaus Ejner; Vølund, A; Frankild, S

    1995-01-01

    The guinea pig maximization test (GPMT) is usually performed with one moderately irritant induction dose of the allergen and gives a qualitative assessment-hazard identification-of the allergenicity of the chemical. We refined the GPMT by applying a multiple dose design and used 30 guinea pigs...

  4. Treatment plan modification using voxel-based weighting factors/dose prescription

    International Nuclear Information System (INIS)

    Wu Chuan; Olivera, Gustavo H; Jeraj, Robert; Keller, Harry; Mackie, Thomas R

    2003-01-01

    Under various clinical situations, it is desirable to modify the original treatment plan to better suit the clinical goals. In this work, a method to help physicians modify treatment plans based on their clinical preferences is proposed. The method uses a weighted quadratic dose objective function. The commonly used organ-/ROI-based weighting factors are expanded to a set of voxel-based weighting factors in order to obtain greater flexibility in treatment plan modification. Two different but equivalent modification schemes based on Rustem's quadratic programming algorithms -modification of a weighting matrix and modification of prescribed doses - are presented. Case studies demonstrated the effectiveness of the two methods with regard to their capability to fine-tune treatment plans

  5. Influence of radiation dose and dose-rate on modification of barley seed radiosensitivity by post-treatment with caffeine

    International Nuclear Information System (INIS)

    Sharma, G.J.

    1987-01-01

    Influence of radiation doses (100, 150 and 200 Gy) and dose-rates (1.27-0.023 Gy/Sec) on the modification of oxic and anoxic radiation damage by caffeine at different concentrations has been investigated using metabolizing barley seeds as test system. As the radiation dose increases from 100 to 200 Gy, the magnitude of oxic and anoxic damages increase at all the dose-rates. Caffeine is able to afford partial radioprotection against the oxic damage, at the same time potentiating the anoxic damage. However, caffeine effect against the oxic and anoxic components of damage depend largely upon the dose of radiation applied and also on the dose-rate used. The possible mechanism of action of caffeine in bringing about the differential modification of oxic and anoxic damages has been discussed. 19 refs., 2 tables. (author)

  6. Maximal safe dose of I-131 after failure of standard fixed dose therapy in patients with differentiated thyroid carcinoma

    International Nuclear Information System (INIS)

    Lee, Jong-Jin; Chung, June-Key; Kim, Sung-Eun; Kang, Won-Jun; Park, Do-Joon; Lee, Dong-Soo; Cho, Bo-Youn; Lee, Myung-Chul

    2008-01-01

    The maximal safe dose (MSD) on the basis of bone marrow irradiation levels allows the delivery of a large amount of I-131 to thyroid cancer tissue. The efficacy of MSD therapy in differentiated metastatic thyroid cancers that persisted after conventional fixed dose therapy is investigated. Forty-seven differentiated thyroid carcinoma patients with non-responsive residual disease despite repetitive fixed dose I-131 therapy were enrolled in this study. Their postoperative pathologies were 43 papillary carcinomas and 4 follicular carcinomas. The MSD was calculated with the Memorial Sloan-Kettering Cancer Center protocol using serial blood samples. The MSDs were administered at intervals of 6 months. Treatment responses were evaluated using I-131 whole-body scans and serum thyroglobulin measurements. The mean calculated MSD was 12.5±2.1 GBq (339.6±57.5 mCi). Of the 46 patients, 7 (14.9%) showed complete remission, 15 (31.9%) partial remission, 19 (40.4%) stable disease, and 6 (12.8%) disease progression. Of the patients who showed complete or partial remission, 15 (65%) showed response after the first MSD session and 6 (26%) showed response after the second session. Twenty-nine patients (62%) experienced transient cytopenia after therapy, but three did not recover to the baseline level. The maximal safe dose provides an effective means of treatment in patients who failed to respond adequately to conventional fixed dose therapy. I-131 MSD therapy can be considered in patients who fail fixed dose therapy. (author)

  7. Dose modification factors in boron neutron capture therapy

    Energy Technology Data Exchange (ETDEWEB)

    Allen, B.J. (Australian Nuclear Science and Technology Organization (ANSTO), Menai (Australia))

    1993-01-01

    The effective treatment depth and therapeutic ratio in boron neutron capture therapy (BNCT) depend on a number of macroscopic dose factors such as boron concentrations in the tumor, normal tissue and blood. However, the role of various microscopic dose modification factors can be of critical importance in the evaluation of normal tissue tolerance levels. An understanding of these factors is valuable in designing BNCT experiments and the selection of appropriate boron compounds. These factors are defined in this paper and applied to the case of brain tumors with particular attention to capillary endothelial cells and oligodendrocytes. (orig.).

  8. A spatially encoded dose difference maximal intensity projection map for patient dose evaluation: A new first line patient quality assurance tool

    Energy Technology Data Exchange (ETDEWEB)

    Hu Weigang; Graff, Pierre; Boettger, Thomas; Pouliot, Jean [Department of Radiation Oncology, University of California, San Francisco, San Francisco, California 94143 (United States); and others

    2011-04-15

    Purpose: To develop a spatially encoded dose difference maximal intensity projection (DD-MIP) as an online patient dose evaluation tool for visualizing the dose differences between the planning dose and dose on the treatment day. Methods: Megavoltage cone-beam CT (MVCBCT) images acquired on the treatment day are used for generating the dose difference index. Each index is represented by different colors for underdose, acceptable, and overdose regions. A maximal intensity projection (MIP) algorithm is developed to compress all the information of an arbitrary 3D dose difference index into a 2D DD-MIP image. In such an algorithm, a distance transformation is generated based on the planning CT. Then, two new volumes representing the overdose and underdose regions of the dose difference index are encoded with the distance transformation map. The distance-encoded indices of each volume are normalized using the skin distance obtained on the planning CT. After that, two MIPs are generated based on the underdose and overdose volumes with green-to-blue and green-to-red lookup tables, respectively. Finally, the two MIPs are merged with an appropriate transparency level and rendered in planning CT images. Results: The spatially encoded DD-MIP was implemented in a dose-guided radiotherapy prototype and tested on 33 MVCBCT images from six patients. The user can easily establish the threshold for the overdose and underdose. A 3% difference between the treatment and planning dose was used as the threshold in the study; hence, the DD-MIP shows red or blue color for the dose difference >3% or {<=}3%, respectively. With such a method, the overdose and underdose regions can be visualized and distinguished without being overshadowed by superficial dose differences. Conclusions: A DD-MIP algorithm was developed that compresses information from 3D into a single or two orthogonal projections while hinting the user whether the dose difference is on the skin surface or deeper.

  9. A spatially encoded dose difference maximal intensity projection map for patient dose evaluation: a new first line patient quality assurance tool.

    Science.gov (United States)

    Hu, Weigang; Graff, Pierre; Boettger, Thomas; Pouliot, Jean

    2011-04-01

    To develop a spatially encoded dose difference maximal intensity projection (DD-MIP) as an online patient dose evaluation tool for visualizing the dose differences between the planning dose and dose on the treatment day. Megavoltage cone-beam CT (MVCBCT) images acquired on the treatment day are used for generating the dose difference index. Each index is represented by different colors for underdose, acceptable, and overdose regions. A maximal intensity projection (MIP) algorithm is developed to compress all the information of an arbitrary 3D dose difference index into a 2D DD-MIP image. In such an algorithm, a distance transformation is generated based on the planning CT. Then, two new volumes representing the overdose and underdose regions of the dose difference index are encoded with the distance transformation map. The distance-encoded indices of each volume are normalized using the skin distance obtained on the planning CT. After that, two MIPs are generated based on the underdose and overdose volumes with green-to-blue and green-to-red lookup tables, respectively. Finally, the two MIPs are merged with an appropriate transparency level and rendered in planning CT images. The spatially encoded DD-MIP was implemented in a dose-guided radiotherapy prototype and tested on 33 MVCBCT images from six patients. The user can easily establish the threshold for the overdose and underdose. A 3% difference between the treatment and planning dose was used as the threshold in the study; hence, the DD-MIP shows red or blue color for the dose difference > 3% or < or = 3%, respectively. With such a method, the overdose and underdose regions can be visualized and distinguished without being overshadowed by superficial dose differences. A DD-MIP algorithm was developed that compresses information from 3D into a single or two orthogonal projections while hinting the user whether the dose difference is on the skin surface or deeper.

  10. Biosphere Dose Conversion Factors for Reasonably Maximally Exposed Individual and Average Member of Critical Group

    International Nuclear Information System (INIS)

    K. Montague

    2000-01-01

    The purpose of this calculation is to develop additional Biosphere Dose Conversion Factors (BDCFs) for a reasonably maximally exposed individual (RMEI) for the periods 10,000 years and 1,000,000 years after the repository closure. In addition, Biosphere Dose Conversion Factors for the average member of a critical group are calculated for those additional radionuclides postulated to reach the environment during the period after 10,000 years and up to 1,000,000 years. After the permanent closure of the repository, the engineered systems within the repository will eventually lose their abilities to contain radionuclide inventory, and the radionuclides will migrate through the geosphere and eventually enter the local water table moving toward inhabited areas. The primary release scenario is a groundwater well used for drinking water supply and irrigation, and this calculation takes these postulated releases and follows them through various pathways until they result in a dose to either a member of critical group or a reasonably maximally exposed individual. The pathways considered in this calculation include inhalation, ingestion, and direct exposure

  11. An estimate of the maximal doses incurred by persons accompanying patients in the waiting area of a nuclear medicine department

    International Nuclear Information System (INIS)

    Dzik-Jurasz, A.S.K.; Farwell, J.

    1997-01-01

    The aim of the study was to make an estimate of the maximal doses that might be incurred by persons accompanying active patients in a nuclear medicine department waiting area. This was in order to determine whether the dose to such individuals approached current legislative or recently recommended limits. Thermoluminescent dosemeters were taped to the walls of the waiting area at waist level to the sitting individual, such that their record would reflect as closely as possible the dose incurred by an individual sitting next to an active patient. Dividing the recorded dose with the total occupancy time of that seat derived an average dose rate. Maximal doses were estimated by the product of the latter and maximal occupancy times. It was assumed that an accompanying individual would have been sitting next to the active patient for their whole duration of stay. The maximum estimates were 278 μSv and 103.2 μSv. These values are likely to be overestimates by the virtue of the TLD integrating the whole dose of its surrounds, especially adjacent active individuals. By current legislation and recent recommendations the values are reassuringly low, but idiosyncrasies in local practice might need to be considered in individual departments. (author)

  12. Motion-encoded dose calculation through fluence/sinogram modification

    International Nuclear Information System (INIS)

    Lu, Weiguo; Olivera, Gustavo H.; Mackie, Thomas R.

    2005-01-01

    Conventional radiotherapy treatment planning systems rely on a static computed tomography (CT) image for planning and evaluation. Intra/inter-fraction patient motions may result in significant differences between the planned and the delivered dose. In this paper, we develop a method to incorporate the knowledge of intra/inter-fraction patient motion directly into the dose calculation. By decomposing the motion into a parallel (to beam direction) component and perpendicular (to beam direction) component, we show that the motion effects can be accounted for by simply modifying the fluence distribution (sinogram). After such modification, dose calculation is the same as those based on a static planning image. This method is superior to the 'dose-convolution' method because it is not based on 'shift invariant' assumption. Therefore, it deals with material heterogeneity and surface curvature very well. We test our method using extensive simulations, which include four phantoms, four motion patterns, and three plan beams. We compare our method with the 'dose-convolution' and the 'stochastic simulation' methods (gold standard). As for the homogeneous flat surface phantom, our method has similar accuracy as the 'dose-convolution' method. As for all other phantoms, our method outperforms the 'dose-convolution'. The maximum motion encoded dose calculation error using our method is within 4% of the gold standard. It is shown that a treatment planning system that is based on 'motion-encoded dose calculation' can incorporate random and systematic motion errors in a very simple fashion. Under this approximation, in principle, a planning target volume definition is not required, since it already accounts for the intra/inter-fraction motion variations and it automatically optimizes the cumulative dose rather than the single fraction dose

  13. Effects of maximal doses of atorvastatin versus rosuvastatin on small dense low-density lipoprotein cholesterol levels

    Science.gov (United States)

    Maximal doses of atorvastatin and rosuvastatin are highly effective in lowering low-density lipoprotein (LDL) cholesterol and triglyceride levels; however, rosuvastatin has been shown to be significantly more effective than atorvastatin in lowering LDL cholesterol and in increasing high-density lipo...

  14. The impact of central lung distance, maximal heart distance, and radiation technique on the volumetric dose of the lung and heart for intact breast radiation

    International Nuclear Information System (INIS)

    Kong, F.-M.; Klein, Eric E.; Bradley, Jeffrey D.; Mansur, David B.; Taylor, Marie E.; Perez, Carlos A.; Myerson, Robert J.; Harms, William B.

    2002-01-01

    Purpose: To investigate the impact of radiographic parameter and radiation technique on the volumetric dose of lung and heart for intact breast radiation. Methods and Materials: Forty patients with both two-dimensional (2D) and computed tomographic (CT) simulations were enrolled in the study. Central lung distance (CLD), maximal heart distance (MHD), and maximal heart length (MHL) were measured under virtual simulation. Four plans were compared for each patient. Plan A used a traditional 2D tangential setup. Plan B used clinical target volume (CTV) based three-dimensional (3D) planning. Both plans C and D used a combination of a medial breast field with shallow tangents. Plan D is a further modification of plan C. Results: Under the traditional tangential setup, the mean ipsilateral lung dose and volume at 20, 30, and 40 Gy correlated linearly with CLD (R = 0.85∼0.91). The mean ipsilateral lung dose (Gy) approximated 4 times the CLD value (cm), whereas the percentage volume (%) of ipsilateral lung at 20, 30, and 40 Gy was about 10 times the CLD (cm). The mean heart dose and percentage volume at 20, 30, and 40 Gy correlated with MHD (R = 0.76∼0.80) and MHL (R 0.65∼0.75). The mean heart dose (Gy) approximated 3 times the MHD value (cm), and the percentage volume (%) of the heart at 10, 20, 30, and 40 Gy was about 6 times MHD (cm). Radiation technique impacted lung and heart dose. The 3D tangential plan (plan B) failed to reduce the volumetric dose of lung and heart from that of the 2D plan (plan A). The medial breast techniques (plans C and D) significantly decreased the volume of lung and heart receiving high doses (30 and 40 Gy). Plan D further decreased the 20 Gy volumes. By use of the medial breast technique, the lung and heart dose were not impacted by original CLD and MHD/MHL. Therefore, the improvement from the tangential technique was more remarkable for patients with CLD ≥ 3.0 cm (p<0.001). Conclusions: The CLD and MHD impact the volumetric dose of

  15. Optimizing fluorescently tethered Hsp90 inhibitor dose for maximal specific uptake by breast tumors

    Science.gov (United States)

    Crouch, Brian T.; Duer, Joy; Wang, Roujia; Gallagher, Jennifer; Hall, Allison; Soo, Mary Scott; Hughes, Philip; Haystead, Timothy A. J.; Ramanujam, Nirmala

    2018-03-01

    Despite improvements in surgical resection, 20-40% of patients undergoing breast conserving surgery require at least one additional re-excision. Leveraging the unique surface expression of heat shock protein 90 (Hsp90), a chaperone protein involved in several key hallmarks of cancer, in breast cancer provides an exciting opportunity to identify residual disease during surgery. We developed a completely non-destructive strategy using HS-27, a fluorescently-tethered Hsp90 inhibitor, to assay surface Hsp90 expression on intact tissue specimens using a fluorescence microendoscope with a field of view of 750 μm and subcellular resolution of 4 μm. HS-27 consists of an FDA approved Hsp90 inhibitor tethered to fluorescein isothiocyanate (EX 488nm, EM 525nm). Here, we optimized ex vivo HS-27 administration in pre-clinical breast cancer models and validated our approach on 21 patients undergoing standard of care ultrasound guided core needle biopsy. HS-27 administration time was fixed at 1- minute to minimize imaging impact on clinical workflow. HS-27 and HS-217 (non-specific control) doses were modulated from 1 μM up to 100 μM to identify the dose maximizing the ratio of specific uptake (HS-27 fluorescence) to non-specific uptake (HS-217 fluorescence). The specificity ratio was maximized at 100 μM and was significantly greater than all other doses (pcancer makes this technology attractive for assessing tumor margins, as one agent can be used for all subtypes.

  16. Practice of radiation dose control for tech-modification items in Qinshan Nuclear Power Plant

    International Nuclear Information System (INIS)

    Zhang Yong; Chen Zhongyu; Xu Hongming; Fan Liguang; Jiang Jianqi; Bu Weidong

    2006-01-01

    In order to improve the safety and reliability of nuclear power plant operation, many tech-modifications related to system or equipment have been completed since operation in Qinshan NPP. this paper introduces radiation dose control for mainly tech-modifications items related to radiation, including radiation protection optimization measures and experience in aspects of item planning, program writing, process control, etc. (authors)

  17. A bio-enabled maximally mild layer-by-layer Kapton surface modification approach for the fabrication of all-inkjet-printed flexible electronic devices

    Science.gov (United States)

    Fang, Yunnan; Hester, Jimmy G. D.; Su, Wenjing; Chow, Justin H.; Sitaraman, Suresh K.; Tentzeris, Manos M.

    2016-12-01

    A bio-enabled, environmentally-friendly, and maximally mild layer-by-layer approach has been developed to surface modify inherently hydrophobic Kapton HN substrates to allow for great printability of both water- and organic solvent-based inks thus facilitating the full-inkjet-printing of flexible electronic devices. Different from the traditional Kapton surface modification approaches which are structure-compromising and use harsh conditions to target, and oxidize and/or remove part of, the surface polyimide of Kapton, the present Kapton surface modification approach targeted the surface electric charges borne by its additive particles, and was not only the first to utilize environmentally-friendly clinical biomolecules to build up a thin film of protamine-heparin complex on Kapton, but also the first to be conducted under minimally destructive and maximally mild conditions. Besides, for electrically charged ink particles, the present surface modification method can enhance the uniformity of the inkjet-printed films by reducing the “coffee ring effect”. As a proof-of-concept demonstration, reduced graphene oxide-based gas sensors, which were flexible, ultra-lightweight, and miniature-sized, were fully-inkjet-printed on surface modified Kapton HN films and tested for their sensitivity to dimethyl methylphosphonate (a nerve agent simulant). Such fabricated sensors survived a Scotch-tape peel test and were found insensitive to repeated bending to a small 0.5 cm radius.

  18. Maximal safe dose therapy of I-131 after failure of standard fixed dose therapy in patients with differentiated thyroid carcinoma

    International Nuclear Information System (INIS)

    Lee, Jong Jin; Seok, Ju Won; Uh, Jae Sun

    2005-01-01

    In patients with recurrent or metastatic differentiated thyroid carcinoma, residual disease despite repetitive fixed dose I-131 therapy presents an awkward situation in terms of treatment decision making. Maximal safe dose (MSD) administration base on bone marrow radiation allows the delivery of a large amount I-131 to thyroid cancer tissue within the safety margin. We investigated the efficacy of MSD in differentiated thyroid cancers, which had persisted after conventional fixed dose therapy. Forty-six patients with differentiated thyroid carcinoma who had non-responsible residual disease despite repetitive fixed dose I-131 therapy were enrolled in this study. The postoperative pathology consisted of 43 papillary carcinomas and 3 follicular carcinomas. MSD was calculated according the Memorial Sloan Kettering Cancer Center protocol using blood samples. MSDs were administered at intervals of at least 6 months. Treatment responses were evaluated using I-131 whole body scan (WBS) and serum thyroglobulin measurements. Mean calculated MSD was 12.5±2.1 GBq. Of the 46 patients, 6 (13.0%) showed complete remission, 15 (32.6%) partial response, 19 (41.3%) stable disease, and 6 (13.0%) disease progression. Thus, about a half of the patients showed complete or partial remission, and of these patients, 14 (67%) showed response after a single MSD administration and 6 (29%) showed response after the second dose of MSD administrations. Twenty-nine patients (63%) experienced transient cytopenia after therapy, and recovered spontaneously with the exception of one. MSD administration is an effective method even in the patients who failed to be treated by conventional fixed dose therapy. MSD therapy of I-131 can be considered in the patients who failed by fixed dose therapy

  19. Linezolid Dose That Maximizes Sterilizing Effect While Minimizing Toxicity and Resistance Emergence for Tuberculosis.

    Science.gov (United States)

    Srivastava, Shashikant; Magombedze, Gesham; Koeuth, Thearith; Sherman, Carleton; Pasipanodya, Jotam G; Raj, Prithvi; Wakeland, Edward; Deshpande, Devyani; Gumbo, Tawanda

    2017-08-01

    Linezolid has an excellent sterilizing effect in tuberculosis patients but high adverse event rates. The dose that would maximize efficacy and minimize toxicity is unknown. We performed linezolid dose-effect and dose-scheduling studies in the hollow fiber system model of tuberculosis (HFS-TB) for sterilizing effect. HFS-TB units were treated with several doses to mimic human-like linezolid intrapulmonary pharmacokinetics and repetitively sampled for drug concentration, total bacterial burden, linezolid-resistant subpopulations, and RNA sequencing over 2 months. Linezolid-resistant isolates underwent whole-genome sequencing. The expression of genes encoding efflux pumps in the first 1 to 2 weeks revealed the same exposure-response patterns as the linezolid-resistant subpopulation. Linezolid-resistant isolates from the 2nd month of therapy revealed mutations in several efflux pump/transporter genes and a LuxR-family transcriptional regulator. Linezolid sterilizing effect was linked to the ratio of unbound 0- to 24-h area under the concentration-time curve (AUC 0-24 ) to MIC. Optimal microbial kill was achieved at an AUC 0-24 /MIC ratio of 119. The optimal sterilizing effect dose for clinical use was identified using Monte Carlo simulations. Clinical doses of 300 and 600 mg/day (or double the dose every other day) achieved this target in 87% and >99% of 10,000 patients, respectively. The susceptibility breakpoint identified was 2 mg/liter. The simulations identified that a 300-mg/day dose did not achieve AUC 0-24 s associated with linezolid toxicity, while 600 mg/day achieved those AUC 0-24 s in linezolid dose of 300 mg/day performed well and should be compared to 600 mg/day or 1,200 mg every other day in clinical trials. Copyright © 2017 Srivastava et al.

  20. Modifying Softball for Maximizing Learning Outcomes in Physical Education

    Science.gov (United States)

    Brian, Ali; Ward, Phillip; Goodway, Jacqueline D.; Sutherland, Sue

    2014-01-01

    Softball is taught in many physical education programs throughout the United States. This article describes modifications that maximize learning outcomes and that address the National Standards and safety recommendations. The modifications focus on tasks and equipment, developmentally appropriate motor-skill acquisition, increasing number of…

  1. Intravenous infusion of docosahexaenoic acid increases serum concentrations in a dose-dependent manner and increases seizure latency in the maximal PTZ model.

    Science.gov (United States)

    Trépanier, Marc-Olivier; Kwong, Kei-Man; Domenichiello, Anthony F; Chen, Chuck T; Bazinet, Richard P; Burnham, W M

    2015-09-01

    Docosahexaenoic acid (DHA) is an omega-3 polyunsaturated fatty acid (n-3 PUFA) that has been shown to raise seizure thresholds in the maximal pentylenetetrazole model following acute subcutaneous (s.c.) administration in rats. Following s.c. administration, however, the dose-response relationship for DHA has shown an inverted U-pattern. The purposes of the present experiment were as follows: (1) to determine the pattern of serum unesterified concentrations resulting from the intravenous (i.v.) infusions of various doses of DHA, (2) to determine the time course of these concentrations following the discontinuation of the infusions, and (3) to determine whether seizure protection in the maximal PTZ model would correlate with serum unesterified DHA levels. Animals received 5-minute i.v. infusions of saline or 25, 50, 100, or 200mg/kg of DHA via a cannula inserted into one of the tail veins. Blood was collected during and after the infusions by means of a second cannula inserted into the other tail vein (Experiment 1). A separate group of animals received saline or 12.5-, 25-, 50-, 100-, or 200 mg/kg DHA i.v. via a cannula inserted into one of the tail veins and were then seizure-tested in the maximal PTZ model either during infusion or after the discontinuation of the infusions. Slow infusions of DHA increased serum unesterified DHA concentrations in a dose-dependent manner, with the 200-mg/kg dose increasing the concentration approximately 260-fold compared with saline-infused animals. Following discontinuation of the infusions, serum concentrations rapidly dropped toward baseline, with half-lives of approximately 40 and 11s for the 25-mg/kg dose and 100-mg/kg dose, respectively. In the seizure-tested animals, DHA significantly increased latency to seizure onset in a dose-dependent manner. Following the discontinuation of infusion, seizure latency rapidly decreased toward baseline. Overall, our study suggests that i.v. infusion of unesterified DHA results in

  2. Time-dose modifications

    International Nuclear Information System (INIS)

    Kian Ang, K.

    1987-01-01

    Changes in fractionation schedule can be made by various approaches. However, from the first principle, it is anticipated that strategies of hyperfractionation and/or accelerated fractionation offer the most promised in improving the therapeutic ratio. Hyperfractionation is defined as a treatment schedule in which a large number of significantly reduced dose fractions (--1.2 Gy/fraction) is used to give a greater total dose in a conventional overall time period. The results of the pilot studies testing the efficacy of hyperfractionation have been encouraging. The most valid clinical trial of pure hyperfractionation, however, is that conducted by the EORTC. This study compared 70 Gy in 35 fractions or 80.5 Gy in 70 fractions over 7 weeks in the treatment of patients with oropharyngeal carcinomas. The local tumor control was significantly improved in the hyperfractionated arm without increasing the morbidity. Accelerated fractionation is defined as a schedule in which the overall time of treatment is reduced without significant changes in the total dose and fraction size. The strategy has been used to treat patients with malignant gliomas, melanomas and Head and Neck cancers. The data in Head and Neck Cancers seem to be promising

  3. Optimization of the dose level for a given treatment plan to maximize the complication-free tumor cure

    International Nuclear Information System (INIS)

    Lind, B.K.; Mavroidis, P.; Hyoedynmaa, S.; Kappas, C.

    1999-01-01

    During the past decade, tumor and normal tissue reactions after radiotherapy have been increasingly quantified in radiobiological terms. For this purpose, response models describing the dependence of tumor and normal tissue reactions on the irradiated volume, heterogeneity of the delivered dose distribution and cell sensitivity variations can be taken into account. The probability of achieving a good treatment outcome can be increased by using an objective function such as P + , the probability of complication-free tumor control. A new procedure is presented, which quantifies P + from the dose delivery on 2D surfaces and 3D volumes and helps the user of any treatment planning system (TPS) to select the best beam orientations, the best beam modalities and the most suitable beam energies. The final step of selecting the prescribed dose level is made by a renormalization of the entire dose plan until the value of P + is maximized. The index P + makes use of clinically established dose-response parameters, for tumors and normal tissues of interest, in order to improve its clinical relevance. The results, using P + , are compared against the assessments of experienced medical physicists and radiation oncologists for two clinical cases. It is observed that when the absorbed dose level for a given treatment plan is increased, the treatment outcome first improves rapidly. As the dose approaches the tolerance of normal tissues the complication-free curve begins to drop. The optimal dose level is often just below this point and it depends on the geometry of each patient and target volume. Furthermore, a more conformal dose delivery to the target results in a higher control rate for the same complication level. This effect can be quantified by the increased value of the P + parameter. (orig.)

  4. Spiral CT and radiation dose

    International Nuclear Information System (INIS)

    Imhof, H.; Schibany, N.; Ba-Ssalamah, A.; Czerny, C.; Hojreh, A.; Kainberger, F.; Krestan, C.; Kudler, H.; Noebauer, I.; Nowotny, R.

    2003-01-01

    Recent studies in the USA and Europe state that computed tomography (CT) scans compromise only 3-5% of all radiological exams, but they contribute 35-45% of total radiation dose to the patient population. These studies lead to concern by several public authorities. Basis of CT-dose measurements is the computed tomography dose index (CTDI), which was established 1981. Nowadays there are several modifications of the CTDI values, which may lead to confusion. It is suggested to use the standardized CTDI-100 w. value together with the dose length product in all CT-examinations. These values should be printed on all CT-images and allows an evaluation of the individualized patient dose. Nowadays, radiologist's aim must be to work at the lowest maximal diagnostic acceptable signal to noise ratio. To decrease radiation dose radiologist should use low kV and mA, but high pitches. Newly developed CT-dose-reduction soft-wares and filters should be installed in all CT-machines. We should critically compare the average dose used for a specific examination with the reference dose used in this country and/or Europe. Greater differences should caution the radiologist. Finally, we as radiologists must check very carefully all indications and recommend alternative imaging methods. But we have also to teach our customers--patients and medical doctors who are non-radiologists--that a 'good' image is not that which show all possible information, but that which visualize 'only' the diagnostic necessary information

  5. Allergenicity evaluation of p-chloro-m-cresol and p-chloro-m-xylenol by non-radioactive murine local lymph-node assay and multiple-dose guinea pig maximization test

    International Nuclear Information System (INIS)

    Yamano, Tetsuo; Shimizu, Mitsuru; Noda, Tsutomu

    2003-01-01

    p-Chloro-m-cresol (PCMC) and p-chloro-m-xylenol (PCMX) are known to cause allergic contact dermatitis. For risk assessment of skin sensitizers, information on dose-response profiles in the induction and elicitation phases and cross-reactivity with analogous chemicals are important. In the non-radioactive local lymph-node assay (LLNA) using 5-bromo-2'-deoxyuridine instead of 3 H-methyl thymidine, significant effect on lymph node cell proliferation was detected at 10% PCMC and 25% PCMX, while in the multiple-dose guinea pig maximization test (GPMT) at least one animal tested in the group was sensitized at a 5 ppm induction dose of either chemical. When mean skin reaction score in an animal group maximally sensitized with each allergen with the GPMT was plotted against log challenge concentration, linear regression lines with high correlations were obtained in both cases. The calculated elicitation threshold was lower for PCMC than PCMX. The area under the linear regression line between the threshold point and 1% of the elicitation concentration, another index of relative elicitation potency, was also greater for PCMC. Bidirectional cross-reactivity between PCMX and PCMC was detected in the GPMT. PCMC was thus identified in both LLNA and GPMT as a stronger sensitizer than PCMX in both the induction and elicitation phases. These results suggest that the non-radioactive LLNA is a simple and useful method for evaluating allergenicity in the induction phase, while the GPMT using a maximally sensitized animal group is more suitable for assessing the dose-response profile and cross-reactivity in the elicitation phase

  6. Design of spray dried insulin microparticles to bypass deposition in the extrathoracic region and maximize total lung dose.

    Science.gov (United States)

    Ung, Keith T; Rao, Nagaraja; Weers, Jeffry G; Huang, Daniel; Chan, Hak-Kim

    2016-09-25

    Inhaled drugs all too often deliver only a fraction of the emitted dose to the target lung site due to deposition in the extrathoracic region (i.e., mouth and throat), which can lead to increased variation in lung exposure, and in some instances increases in local and systemic side effects. For aerosol medications, improved targeting to the lungs may be achieved by tailoring the micromeritic properties of the particles (e.g., size, density, rugosity) to minimize deposition in the mouth-throat and maximize the total lung dose. This study evaluated a co-solvent spray drying approach to modulate particle morphology and dose delivery characteristics of engineered powder formulations of insulin microparticles. The binary co-solvent system studied included water as the primary solvent mixed with an organic co-solvent, e.g., ethanol. Factors such as the relative rate of evaporation of each component of a binary co-solvent mixture, and insulin solubility in each component were considered in selecting feedstock compositions. A water-ethanol co-solvent mixture with a composition range considered suitable for modulating particle shell formation during drying was selected for experimental investigation. An Alberta Idealized Throat model was used to evaluate the in vitro total lung dose of a series of spray dried insulin formulations engineered with different bulk powder properties and delivered with two prototype inhalers that fluidize and disperse powder using different principles. The in vitro total lung dose of insulin microparticles was improved and favored for powders with low bulk density and small primary particle size, with reduction of deposition in the extrathoracic region. The results demonstrated that a total lung dose >95% of the delivered dose can be achieved with engineered particles, indicating a high degree of lung targeting, almost completely bypassing deposition in the mouth-throat. Copyright © 2016 Elsevier B.V. All rights reserved.

  7. Modification of damage following low doses

    International Nuclear Information System (INIS)

    Braby, L.A.; Nelson, J.M.; Metting, N.F.

    1988-01-01

    At very low doses the damage-interaction mechanism is responsible for very little lethal or potentially lethal damage, and repair of the latter should essentially disappear. An alternative model suggests that potentially lethal damage is either repaired with a constant half time or misrepaired at a rate which is proportional to the square of the damage concentration. In this case, as the dose decreases, the probability of misrepair decreases faster than the probability of repair, and repair becomes a more pronounced feature of the cell response. Since the consequence of unrepaired damage is an important question in determining the effects of low doses of radiation delivered at low dose rates, we have attempted to determine which of these two types of models is consistent with the response of plateau-phase CHO cells. In the earlier experiments, there was no indication of repair after a 50-rad exposure with a 24-hour split dose or plating delay; in fact, immediate plating resulted in survival slightly above control and delayed plating in survival slightly below the control value

  8. Maximization of bremsstrahlung and K-series production efficiencies in flash x-ray tubes

    International Nuclear Information System (INIS)

    Krehl, P.

    1986-01-01

    Historically, x-ray output of flash x-ray tubes was maximized empirically by changing the electrode geometry and varying the capacitance of the pulse generator. With the advent of high-voltage, low-impedance transmission lines, short-duration, high-current pulses could be generated with ease. An appropriate line scaling should assure that dose maximization is not reached at the expense of pulse prolongation which would reduce stop motion capability, but rather that dose rate should be maximized. Additionally, anode evaporation in the arc phase should be minimized to enhance tube life

  9. Analysis of various modifications in spectra analysis on accuracy of dose reconstructions in EPR dosimetry in tooth enamel

    Energy Technology Data Exchange (ETDEWEB)

    Ciesielski, B., E-mail: bciesiel@gumed.edu.pl [Department of Physics and Biophysics, Medical University of Gdansk, Debinki 1, 80-211 Gdansk (Poland); Kaminska, J. [Department of Oncology and Radiotherapy, Medical University of Gdansk, Debinki 7, 80-211 Gdansk (Poland); Emerich, K. [Department of Paediatric Dentistry, Medical University of Gdansk, Orzeszkowej 18, 80-208 Gdansk (Poland)

    2011-09-15

    The results of EPR measurements performed due to our participation in the 4th International Comparison of EPR Dosimetry using tooth enamel were used to analyze the effects of modifications in numerical analysis of the measured spectra on precision and accuracy of reconstructed doses. The studied modifications included effects of: (1) a use of Mn{sup 2+} standard, (2) variations in experimental native background signals of tooth enamel used for dose reconstructions, (3) signal filtration, (4) subtraction of empty tube spectra, and (5) variations in the spectra ranges used for calculations (fitting windows). It was shown, that the use of a Mn standard, for normalization of intensities of the recorded signals in the spectra processing, strongly increased the dosimetric accuracy. The regression lines of the doses reconstructed using different background spectra against nominal doses, obtained without Mn standard, had slopes about 30% higher and their scatter range was about 2 times higher than the same parameters obtained when Mn standard was applied in the spectra processing. Accuracy of the measured doses characterized by root mean square deviations from the nominal doses was 71 mGy for calculations with Mn standard and 241 mGy without normalization to Mn lines. Despite the large beneficial effect of the use of Mn standard on accuracy (root mean square deviations of the data, slope of the regression lines), it did not significantly improve the dosimetry performance characterized by the critical dose and detection limit. The smoothing of the spectra by 9 point filtration resulted in 1.6% increase of the reconstructed doses. The subtraction of empty tube spectrum had no effect on precision and accuracy of the dose reconstruction. The performance parameters were also practically insensitive to a choice of a width of the spectral window used for the analysis, provided it encompassed the {approx}1.6 mT range covering the main peaks of the radiation induced signal in

  10. The effects of low and moderate doses of caffeine supplementation on upper and lower body maximal voluntary concentric and eccentric muscle force.

    Science.gov (United States)

    Tallis, Jason; Yavuz, Harley C M

    2018-03-01

    Despite the growing quantity of literature exploring the effect of caffeine on muscular strength, there is a dearth of data that directly explores differences in erogenicity between upper and lower body musculature and the dose-response effect. The present study sought to investigate the effects of low and moderate doses of caffeine on the maximal voluntary strength of the elbow flexors and knee extensors. Ten nonspecifically strength-trained, recreationally active participants (aged 21 ± 0.3 years) completed the study. Using a randomised, counterbalanced, and double-blind approach, isokinetic concentric and eccentric strength was measured at 60 and 180°/s following administration of a placebo, 3 mg·kg -1 body mass caffeine, and 6 mg·kg -1 body mass caffeine. There was no effect of caffeine on the maximal voluntary concentric and eccentric strength of the elbow flexors, or the eccentric strength of the knee extensors. Both 3 and 6 mg·kg -1 body mass caffeine caused a significant increase in peak concentric force of the knee extensors at 180°/s. No difference was apparent between the 2 concentrations. Only 6 mg·kg -1 body mass caused an increase in peak concentric force during repeated contractions. The results infer that the effective caffeine concentration to evoke improved muscle performance may be related to muscle mass and contraction type. The present work indicates that a relatively low dose of caffeine treatment may be effective for improving lower body muscular strength, but may have little benefit for the strength of major muscular groups of the upper body.

  11. A new dose of maximal-intensity interval training in hypoxia to improve body composition and hemoglobin and hematocrit levels: a pilot study.

    Science.gov (United States)

    Camacho-Cardenosa, Marta; Camacho-Cardenosa, Alba; Martínez Guardado, Ismael; Marcos-Serrano, Marta; Timon, Rafael; Olcina, Guillermo

    2017-01-01

    This pilot study had the aim to determine the effects of a new dose of maximal-intensity interval training in hypoxia in active adults. Twenty-four university student volunteers were randomly assigned to three groups: hypoxia group, normoxia group or control group. The eight training sessions consisted of 2 sets of 5 repeated sprints of 10 seconds with a recovery of 20 seconds between sprints and a recovery period of 10 minutes between sets. Body composition was measured following standard procedures. A blood sample was taken for an immediate hematocrit (HCT) and hemoglobin (Hb) concentration assessment. An all-out 3-ute test was performed to evaluate ventilation parameters and power. HCT and Hb were significantly higher for the hypoxia group in Post- and Det- (P=0.01; P=0.03). Fat mass percentage was significantly lower for the hypoxia group in both assessments (P=0.05; P=0.05). The hypoxia group underwent a significant increase in mean power after the recovery period. A new dose of 8 sessions of maximal-intensity interval training in hypoxia is enough to decrease the percentage of fat mass and to improve HCT and Hb parameters and mean muscle power in healthy and active adults.

  12. Incidence of cold-induced peripheral neuropathy and dose modification of adjuvant oxaliplatin-based chemotherapy for patients with colorectal cancer

    DEFF Research Database (Denmark)

    Altaf, Rahim; Lund Brixen, Annette; Kristensen, Bent

    2014-01-01

    BACKGROUND: The CAPOX regimen is used for adjuvant treatment of colorectal cancer. A well-known side effect of oxaliplatin, which often leads to dose modification (DM), is acute neuropathy (AN). AN is provoked by cold, and it could therefore be expected that the degree of AN and thereby DM is more...

  13. Obtaining plant Miscanthus sacchariflorus (Maxim. Hack and Miscanthus sinensis Andersson in vitro culture by indirect morphogenesis

    Directory of Open Access Journals (Sweden)

    С. М. Гонтаренко

    2017-03-01

    Full Text Available Purpose. To obtain Miscanthus sacchariflorus (Maxim. Hack and Miscanthus sinensis Andersson in vitro culture by indirect morphogenesis. Methods. Biotechnological procedures, mathematical and statistical analyses. Results. Composition of nutrient medium was developed intended for induction of callusogenesis from Miscanthus seeds with a poor germination and viability of seedlings – Murashige and Skoog (MS medium was modified for the amount of macroelements (half-dose that was supplemented with amino acids (300 mg/l of glutamic acid, 50 mg/l of aspartic acid, 5 mg/l of tyrosine, 3 mg/l of arginine, 2 mg/l of hydroxyproline and plant growth regulators [2,5 mg/l of 2.4D (2.4-Dichlorophenoxyacetic acid, 0,6 mg/l of BAP (6-Benzyl-aminopurine and 0,3 mg/l of ABA (Abscisic acid]. Composition of nutrient medium was developed for regeneration of microplants from callus – agar MS medium was modified for the amount of macroelements (half-dose supplemented with vitamins: 10 mg/l of thiaminum, 1,0 mg/l of pyridoxine, 1,0 mg/l of nicotinic acid (by White, 1,0 mg/l of ascorbic acid, 250 mg/l of glutamic acid, 2,0 mg/l of BAP, 0,3 mg/l of NAA (Naphthaleneacetic acid. On this medium, 100% regeneration of M. sacchariflorus (Maxim. Hack and 50% regeneration of M. sinensis Andersson was obtained. Due to media modification aimed at initiating callusogenesis and microplants regeneration, reproduction factor of M. sinensis was increased 20 times at the average, M. sacchariflorus – 35–40 times. Conclusions. Plants of M. sacchariflorus (Maxim. Hack and M. sinensis Andersson were obtained in vitro culture by initiation of callusogenes and microplants regeneration from the Miscanthus seeds with poor germination and viability on nutrient media of certain composition.

  14. Application of radiation technology in starch modification

    International Nuclear Information System (INIS)

    Chen Huiyuan; Peng Zhigang; Ding Zhongmin; Lu Jiajiu

    2007-01-01

    In order to commercialize the radiation modification of starch, corn starch was irradiated with different dose of 60 Co gamma radiations. Some basic physical and chemical properties of the resulted modified starch paste were measured with emphasis on the viscosity stability and tensile strength. The results indicate that irradiation of corn starch with a dose of 4-10 kGy can decrease its viscosity to 5-14 mPa·s, and the tensile strength can meet the standard set up for textile paste. In comparison with chemical modification for starch, radiation modification is simpler in technology, more convenient in operation, more stable in modification quality, and easier to control. The mechanism of radiation modification of starch was also discussed. (authors)

  15. Compendium of cost-effectiveness evaluations of modifications for dose reduction at nuclear power plants

    International Nuclear Information System (INIS)

    Baum, J.W.; Matthews, G.R.

    1985-12-01

    This report summarizes available information on cost effectiveness of engineering modifications potentially valuable for dose reduction at nuclear power plants. Data were gathered from several US utilities, published literature, equipment and service suppliers, and recent technical meetings. Five simplified econometric models were employed to evaluate data and arrive at a value for cost effectiveness expressed in either (a) dollars/rem, or (b) total dollar savings calculated using a nominal value of $1000/rem. Models employed were: a basic model with no consideration given to the time value of money; two models in which discounting was used to evaluate costs and savings in terms of present values; and two models in which income taxes and revenue requirements were considered. Results from different models varied by as much as a factor of 10, and were generally lowest for the basic model and highest for the before-tax revenue requirements model. Results for 151 evaluations employing different assumptions concerning number of plants per site and outage impacts were tabulated in order of decreasing cost effectiveness. Twenty-five evaluations were identified as exceptionally cost effective since both costs and dose were saved. Forty evaluations indicated highly cost-effective changes based on costs below $1000/rem saved using results of the present-worth model that included discounting of future dose savings

  16. Tri-maximal vs. bi-maximal neutrino mixing

    International Nuclear Information System (INIS)

    Scott, W.G

    2000-01-01

    It is argued that data from atmospheric and solar neutrino experiments point strongly to tri-maximal or bi-maximal lepton mixing. While ('optimised') bi-maximal mixing gives an excellent a posteriori fit to the data, tri-maximal mixing is an a priori hypothesis, which is not excluded, taking account of terrestrial matter effects

  17. Quantitative comparison of the results obtained by the multiple-dose guinea pig maximization test and the non-radioactive murine local lymph-node assay for various biocides.

    Science.gov (United States)

    Yamano, Tetsuo; Shimizu, Mitsuru; Noda, Tsutomu

    2005-07-01

    We compared the results of the multiple-dose guinea pig maximization test (GPMT) and the non-radioactive murine local lymph-node assay (LLNA) for various biocides. Thirteen out of 17 positive biocides in the GPMT gave positive results in the LLNA. In the GPMT, the minimum first induction doses ranged over four orders (0.00005-0.5%), while elicitation-threshold doses, which were evaluated using an optimally sensitized group of animals in the multiple-dose studies, ranged over five orders (0.00006-2.8%). In the LLNA, minimum induction doses ranged over more than three orders (0.01-30%). With respect to 13 biocides that were positive in both the GPMT and the LLNA, results were quantitatively compared. When compared after conversion to corresponding area doses (microg/cm), the minimum doses required to elicit skin reaction in guinea pigs were always lower than that for induction in mice with all biocides. Correlation between minimum induction doses from the GPMT and the LLNA seemed poor (r=0.57), while that between minimum induction doses in the LLNA and elicitation-threshold doses in the GPMT was relatively good (r=0.73). The results suggest the possibility to estimate human elicitation-threshold doses, which are definitely lacking in the process of risk assessment for skin-sensitizers, from the data of the LLNA.

  18. Quantitative comparison of the results obtained by the multiple-dose guinea pig maximization test and the non-radioactive murine local lymph-node assay for various biocides

    International Nuclear Information System (INIS)

    Yamano, Tetsuo; Shimizu, Mitsuru; Noda, Tsutomu

    2005-01-01

    We compared the results of the multiple-dose guinea pig maximization test (GPMT) and the non-radioactive murine local lymph-node assay (LLNA) for various biocides. Thirteen out of 17 positive biocides in the GPMT gave positive results in the LLNA. In the GPMT, the minimum first induction doses ranged over four orders (0.00005-0.5%), while elicitation-threshold doses, which were evaluated using an optimally sensitized group of animals in the multiple-dose studies, ranged over five orders (0.00006-2.8%). In the LLNA, minimum induction doses ranged over more than three orders (0.01-30%). With respect to 13 biocides that were positive in both the GPMT and the LLNA, results were quantitatively compared. When compared after conversion to corresponding area doses (μg/cm), the minimum doses required to elicit skin reaction in guinea pigs were always lower than that for induction in mice with all biocides. Correlation between minimum induction doses from the GPMT and the LLNA seemed poor (r = 0.57), while that between minimum induction doses in the LLNA and elicitation-threshold doses in the GPMT was relatively good (r = 0.73). The results suggest the possibility to estimate human elicitation-threshold doses, which are definitely lacking in the process of risk assessment for skin-sensitizers, from the data of the LLNA

  19. Ergogenic effect of varied doses of coffee-caffeine on maximal ...

    African Journals Online (AJOL)

    Endurance performance index (VO2 max, run time & number of exercise laps) were measured and recorded. Result: Repeated measures ANOVA was used to assess the level of significant difference between caffeine doses and placebo dose in VO2 max, run time and number of exercise laps. The result showed no ...

  20. Outcomes of Direct Vision Internal Urethrotomy for Bulbar Urethral Strictures: Technique Modification with High Dose Triamcinolone Injection

    Directory of Open Access Journals (Sweden)

    Rishi Modh

    2015-01-01

    Full Text Available Objective. To evaluate the recurrence rate of bulbar urethral strictures managed with cold knife direct vision internal urethrotomy and high dose corticosteroid injection. Methods. 28 patients with bulbar urethral strictures underwent direct vision internal urethrotomy with high dose triamcinolone injection into the periurethral tissue and were followed up for recurrence. Results. Our cohort had a mean age of 60 years and average stricture length of 1.85 cm, and 71% underwent multiple previous urethral stricture procedures with an average of 5.7 procedures each. Our technique modification of high dose corticosteroid injection had a recurrence rate of 29% at a mean follow-up of 20 months with a low rate of urinary tract infections. In patients who failed treatment, mean time to stricture recurrence was 7 months. Patients who were successfully treated had significantly better International Prostate Symptom Scores at 6, 9, and 12 months. There was no significant difference in maximum flow velocity on Uroflowmetry at last follow-up but there was significant difference in length of follow-up (p=0.02. Conclusions. High dose corticosteroid injection at the time of direct vision internal urethrotomy is a safe and effective procedure to delay anatomical and symptomatic recurrence of bulbar urethral strictures, particularly in those who are poor candidates for urethroplasty.

  1. Outcomes of Direct Vision Internal Urethrotomy for Bulbar Urethral Strictures: Technique Modification with High Dose Triamcinolone Injection.

    Science.gov (United States)

    Modh, Rishi; Cai, Peter Y; Sheffield, Alyssa; Yeung, Lawrence L

    2015-01-01

    Objective. To evaluate the recurrence rate of bulbar urethral strictures managed with cold knife direct vision internal urethrotomy and high dose corticosteroid injection. Methods. 28 patients with bulbar urethral strictures underwent direct vision internal urethrotomy with high dose triamcinolone injection into the periurethral tissue and were followed up for recurrence. Results. Our cohort had a mean age of 60 years and average stricture length of 1.85 cm, and 71% underwent multiple previous urethral stricture procedures with an average of 5.7 procedures each. Our technique modification of high dose corticosteroid injection had a recurrence rate of 29% at a mean follow-up of 20 months with a low rate of urinary tract infections. In patients who failed treatment, mean time to stricture recurrence was 7 months. Patients who were successfully treated had significantly better International Prostate Symptom Scores at 6, 9, and 12 months. There was no significant difference in maximum flow velocity on Uroflowmetry at last follow-up but there was significant difference in length of follow-up (p = 0.02). Conclusions. High dose corticosteroid injection at the time of direct vision internal urethrotomy is a safe and effective procedure to delay anatomical and symptomatic recurrence of bulbar urethral strictures, particularly in those who are poor candidates for urethroplasty.

  2. Position modification and actual radiation dose in parotids for head and neck cancers treated with TomoTherapy

    International Nuclear Information System (INIS)

    Jiang Huayong; Zhang Yongqian; Wang Yadi; Xu Weidong; Gao Junmao; Zhang Fuli; Yao Bo

    2014-01-01

    Objective: To analyze the impact of parotid's position and volume changing on radiation dose for head and neck cancer treated with TomoTherapy. Methods: Totally 12 patients with head and neck cancer were treated with TomoTherapy. Before the treatment, the dose distribution was recalculated with MVCT images, which would obtain the parameters of position, volume and actual radiation dose for parotids. Results: The volume of parotids in Plan2 was significantly lower than in Plan1, and the percentage reduction was 29.06% and 31.78% for left and right parotid, respectively (Z = 6.77, 3.06, P < 0.05). Distance between the COM(center of mass) of parotids and the midline of body was significantly smaller in Plan2 than in Plan1, and the percentage reduction was 6.72% and 6.19% (t = 5.14, 5.80, P < 0.05) at left and right side, respectively. Average dose and V_2_6 for both parotids were higher than those in Plan1, increasing by an average of 37.74%, 25.08% (Z = -6.03, -5.31, P < 0.05) for left parotid and 30.45%, 19.33% (Z = -5.43, -3.26, P < 0.05) for right parotid, respectively. Conclusions: The actual radiation dose to parotids was significantly increased during the radiation therapy for patients with head and neck cancer. There was a linear correlation between the decrease of distance between the COM of parotids and the midline of body and the percentage increase of parotids' radiation dose. No correlation between the reduction of parotids' volume and dose to parotids. In order to reduce the parotids' radiation dose, modification of treatment plan at the appropriate time is essential. (authors)

  3. Effect of small doses of ionizing radiation on motility, rosette formation, and antioxidant state of leukocytes under modification of G-proteins by cholera and pertussis toxins

    International Nuclear Information System (INIS)

    Zhirnov, V.V.; Luik, A.I.; Metelitsa, L.A.; Mogilevich, S.E.; Charochkina, L.L.

    2000-01-01

    The responses of motility and rosette formation of leukocytes to small radioactive doses (from 6 centre dot 10 -10 to 6 centre dot 10 -4 Gy) are studied. The influence of these doses on cell functions and oxidative homeostasis are investigated under the modification of transducing components of membrane signal pathways (adenylate cyclase and polyphosphoinositide cascades) with pertussis and cholera toxins

  4. Maximizing the biological effect of proton dose delivered with scanned beams via inhomogeneous daily dose distributions

    Energy Technology Data Exchange (ETDEWEB)

    Zeng Chuan; Giantsoudi, Drosoula; Grassberger, Clemens; Goldberg, Saveli; Niemierko, Andrzej; Paganetti, Harald; Efstathiou, Jason A.; Trofimov, Alexei [Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts 02114 (United States)

    2013-05-15

    Purpose: Biological effect of radiation can be enhanced with hypofractionation, localized dose escalation, and, in particle therapy, with optimized distribution of linear energy transfer (LET). The authors describe a method to construct inhomogeneous fractional dose (IFD) distributions, and evaluate the potential gain in the therapeutic effect from their delivery in proton therapy delivered by pencil beam scanning. Methods: For 13 cases of prostate cancer, the authors considered hypofractionated courses of 60 Gy delivered in 20 fractions. (All doses denoted in Gy include the proton's mean relative biological effectiveness (RBE) of 1.1.) Two types of plans were optimized using two opposed lateral beams to deliver a uniform dose of 3 Gy per fraction to the target by scanning: (1) in conventional full-target plans (FTP), each beam irradiated the entire gland, (2) in split-target plans (STP), beams irradiated only the respective proximal hemispheres (prostate split sagittally). Inverse planning yielded intensity maps, in which discrete position control points of the scanned beam (spots) were assigned optimized intensity values. FTP plans preferentially required a higher intensity of spots in the distal part of the target, while STP, by design, employed proximal spots. To evaluate the utility of IFD delivery, IFD plans were generated by rearranging the spot intensities from FTP or STP intensity maps, separately as well as combined using a variety of mixing weights. IFD courses were designed so that, in alternating fractions, one of the hemispheres of the prostate would receive a dose boost and the other receive a lower dose, while the total physical dose from the IFD course was roughly uniform across the prostate. IFD plans were normalized so that the equivalent uniform dose (EUD) of rectum and bladder did not increase, compared to the baseline FTP plan, which irradiated the prostate uniformly in every fraction. An EUD-based model was then applied to estimate tumor

  5. Maximizing the biological effect of proton dose delivered with scanned beams via inhomogeneous daily dose distributions

    International Nuclear Information System (INIS)

    Zeng Chuan; Giantsoudi, Drosoula; Grassberger, Clemens; Goldberg, Saveli; Niemierko, Andrzej; Paganetti, Harald; Efstathiou, Jason A.; Trofimov, Alexei

    2013-01-01

    Purpose: Biological effect of radiation can be enhanced with hypofractionation, localized dose escalation, and, in particle therapy, with optimized distribution of linear energy transfer (LET). The authors describe a method to construct inhomogeneous fractional dose (IFD) distributions, and evaluate the potential gain in the therapeutic effect from their delivery in proton therapy delivered by pencil beam scanning. Methods: For 13 cases of prostate cancer, the authors considered hypofractionated courses of 60 Gy delivered in 20 fractions. (All doses denoted in Gy include the proton's mean relative biological effectiveness (RBE) of 1.1.) Two types of plans were optimized using two opposed lateral beams to deliver a uniform dose of 3 Gy per fraction to the target by scanning: (1) in conventional full-target plans (FTP), each beam irradiated the entire gland, (2) in split-target plans (STP), beams irradiated only the respective proximal hemispheres (prostate split sagittally). Inverse planning yielded intensity maps, in which discrete position control points of the scanned beam (spots) were assigned optimized intensity values. FTP plans preferentially required a higher intensity of spots in the distal part of the target, while STP, by design, employed proximal spots. To evaluate the utility of IFD delivery, IFD plans were generated by rearranging the spot intensities from FTP or STP intensity maps, separately as well as combined using a variety of mixing weights. IFD courses were designed so that, in alternating fractions, one of the hemispheres of the prostate would receive a dose boost and the other receive a lower dose, while the total physical dose from the IFD course was roughly uniform across the prostate. IFD plans were normalized so that the equivalent uniform dose (EUD) of rectum and bladder did not increase, compared to the baseline FTP plan, which irradiated the prostate uniformly in every fraction. An EUD-based model was then applied to estimate tumor

  6. Maximizing the biological effect of proton dose delivered with scanned beams via inhomogeneous daily dose distributions.

    Science.gov (United States)

    Zeng, Chuan; Giantsoudi, Drosoula; Grassberger, Clemens; Goldberg, Saveli; Niemierko, Andrzej; Paganetti, Harald; Efstathiou, Jason A; Trofimov, Alexei

    2013-05-01

    Biological effect of radiation can be enhanced with hypofractionation, localized dose escalation, and, in particle therapy, with optimized distribution of linear energy transfer (LET). The authors describe a method to construct inhomogeneous fractional dose (IFD) distributions, and evaluate the potential gain in the therapeutic effect from their delivery in proton therapy delivered by pencil beam scanning. For 13 cases of prostate cancer, the authors considered hypofractionated courses of 60 Gy delivered in 20 fractions. (All doses denoted in Gy include the proton's mean relative biological effectiveness (RBE) of 1.1.) Two types of plans were optimized using two opposed lateral beams to deliver a uniform dose of 3 Gy per fraction to the target by scanning: (1) in conventional full-target plans (FTP), each beam irradiated the entire gland, (2) in split-target plans (STP), beams irradiated only the respective proximal hemispheres (prostate split sagittally). Inverse planning yielded intensity maps, in which discrete position control points of the scanned beam (spots) were assigned optimized intensity values. FTP plans preferentially required a higher intensity of spots in the distal part of the target, while STP, by design, employed proximal spots. To evaluate the utility of IFD delivery, IFD plans were generated by rearranging the spot intensities from FTP or STP intensity maps, separately as well as combined using a variety of mixing weights. IFD courses were designed so that, in alternating fractions, one of the hemispheres of the prostate would receive a dose boost and the other receive a lower dose, while the total physical dose from the IFD course was roughly uniform across the prostate. IFD plans were normalized so that the equivalent uniform dose (EUD) of rectum and bladder did not increase, compared to the baseline FTP plan, which irradiated the prostate uniformly in every fraction. An EUD-based model was then applied to estimate tumor control probability

  7. Intravascular ultrasound based dose assessment in endovascular brachytherapy

    International Nuclear Information System (INIS)

    Catalano, Gianpiero; Tamburini, Vittorio; Colombo, Antonio; Nishida, Takahiro; Parisi, Giovanni; Mazzetta, Chiara; Orecchia, Roberto

    2003-01-01

    Background: the role of endovascular brachytherapy in restenosis prevention is well documented. Dose is usually prescribed at a fixed distance from the source axis by angiographic quantification of vessel diameter. Recently, intravascular ultrasound (IVUS) was introduced in dose prescription, allowing a better evaluation of the vessel anatomy. This study retrospectively explores the difference between prescription following angiographic vessel sizing and delivered dose calculated with IVUS. Methods and results: Seventeen lesions were studied with IVUS, identifying on irradiated segment, three sections on which measuring minimal and maximal distance from the centre of IVUS catheter to the adventitia; using dedicated software, corresponding doses were calculated. The dose ranged widely, with maximal and minimal values of 71.6 and 4.9 Gy; furthermore, heterogeneity in dose among different sections was observed. In the central section, the maximal dose was 206% of the one prescribed with the QCA model at 2 mm from the source axis, while the minimal dose was 96%. In proximal and distal sections, respective values were 182, 45, 243, and 122%. Conclusions: Our analysis confirmed the dose inhomogeneity delivered with an angiographic fixed-dose prescription strategy. A dose variation was found along the irradiated segment due to the differences in vessel thickness. IVUS emerged as an important tool in endovascular brachytherapy, especially for irregular-shaped vessels

  8. Phenomenology of maximal and near-maximal lepton mixing

    International Nuclear Information System (INIS)

    Gonzalez-Garcia, M. C.; Pena-Garay, Carlos; Nir, Yosef; Smirnov, Alexei Yu.

    2001-01-01

    The possible existence of maximal or near-maximal lepton mixing constitutes an intriguing challenge for fundamental theories of flavor. We study the phenomenological consequences of maximal and near-maximal mixing of the electron neutrino with other (x=tau and/or muon) neutrinos. We describe the deviations from maximal mixing in terms of a parameter ε(equivalent to)1-2sin 2 θ ex and quantify the present experimental status for |ε| e mixing comes from solar neutrino experiments. We find that the global analysis of solar neutrino data allows maximal mixing with confidence level better than 99% for 10 -8 eV 2 ∼ 2 ∼ -7 eV 2 . In the mass ranges Δm 2 ∼>1.5x10 -5 eV 2 and 4x10 -10 eV 2 ∼ 2 ∼ -7 eV 2 the full interval |ε| e mixing in atmospheric neutrinos, supernova neutrinos, and neutrinoless double beta decay

  9. Effect of Maximal Versus Supra-Maximal Exhausting Race on Lipid Peroxidation, Antioxidant Activity and Muscle-Damage Biomarkers in Long-Distance and Middle-Distance Runners.

    Science.gov (United States)

    Mohamed, Said; Lamya, Ncir; Hamda, Mansour

    2016-03-01

    Exhausting physical exercise increases lipid peroxidation and causes important muscle damages. The human body tries to mitigate these adverse effects by mobilizing its antioxidant defenses. This study aims to investigate the effect of a maximal versus supra-maximal race sustained until exhaustion on lipid peroxidation, antioxidant activity and muscle-damage biomarkers in trained (i.e. long-distance and middle-distance runners) and sedentary subjects. The study has been carried out on 8 middle-distance runners (MDR), 9 long-distance runners (LDR), and 8 sedentary subjects (SS). Each subject has undergone two exhaustive running tests, the first one is an incremental event (VAMEVAL test), the second one is a constant supra-maximal intensity test (limited-time test). Blood samples were collected at rest and immediately after each test. A significant increase in malondialdehyde (MDA) concentrations was observed in SS and MDR after the VAMEVAL test and in LDR after the Limited-Time test. A significant difference was also observed between LDR and the other two groups after the VAMEVAL test, and between LDR and MDR after the Limited-Time test. Significant modifications, notably, in myoglobin, CK, LDH, IL-6, TNF-α, and TAS were likewise noted but depending on the race-type and the sportive specialty. Maximal and supra-maximal races induce a significant increase in lipid peroxidation and cause non-negligible inflammation and muscle damage. These effects were relatively related to the physical exercise type and the sportive specialty.

  10. Optimal dose selection accounting for patient subpopulations in a randomized Phase II trial to maximize the success probability of a subsequent Phase III trial.

    Science.gov (United States)

    Takahashi, Fumihiro; Morita, Satoshi

    2018-02-08

    Phase II clinical trials are conducted to determine the optimal dose of the study drug for use in Phase III clinical trials while also balancing efficacy and safety. In conducting these trials, it may be important to consider subpopulations of patients grouped by background factors such as drug metabolism and kidney and liver function. Determining the optimal dose, as well as maximizing the effectiveness of the study drug by analyzing patient subpopulations, requires a complex decision-making process. In extreme cases, drug development has to be terminated due to inadequate efficacy or severe toxicity. Such a decision may be based on a particular subpopulation. We propose a Bayesian utility approach (BUART) to randomized Phase II clinical trials which uses a first-order bivariate normal dynamic linear model for efficacy and safety in order to determine the optimal dose and study population in a subsequent Phase III clinical trial. We carried out a simulation study under a wide range of clinical scenarios to evaluate the performance of the proposed method in comparison with a conventional method separately analyzing efficacy and safety in each patient population. The proposed method showed more favorable operating characteristics in determining the optimal population and dose.

  11. Maximally effective dosing regimens of meropenem in patients with septic shock

    DEFF Research Database (Denmark)

    Sjövall, Fredrik; Alobaid, Abdulaziz S; Wallis, Steven C

    2018-01-01

    was required for both empirical and targeted treatment. In patients with a CL CR of ≤ 100 mL/min, successful concentration targets could be reached with intermittent dosing of 1000 mg/8 h. Conclusions: In patients with septic shock and possible augmented renal clearance, doses should be increased and...

  12. Pharmacokinetics of detomidine administered to horses at rest and after maximal exercise.

    Science.gov (United States)

    Hubbell, J A E; Sams, R A; Schmall, L M; Robertson, J T; Hinchcliff, K W; Muir, W W

    2009-05-01

    Increased doses of detomidine are required to produce sedation in horses after maximal exercise compared to calm or resting horses. To determine if the pharmacokinetics of detomidine in Thoroughbred horses are different when the drug is given during recuperation from a brief period of maximal exercise compared to administration at rest. Six Thoroughbred horses were preconditioned by exercising them on a treadmill. Each horse ran a simulated race at a treadmill speed that caused it to exercise at 120% of its maximal oxygen consumption. One minute after the end of exercise, horses were treated with detomidine. Each horse was treated with the same dose of detomidine on a second occasion a minimum of 14 days later while standing in a stocks. Samples of heparinised blood were obtained at various time points on both occasions. Plasma detomidine concentrations were determined by liquid chromatography-mass spectrometry. The plasma concentration vs. time data were analysed by nonlinear regression analysis. Median back-extrapolated time zero plasma concentration was significantly lower and median plasma half-life and median mean residence time were significantly longer when detomidine was administered after exercise compared to administration at rest. Median volume of distribution was significantly higher after exercise but median plasma clearance was not different between the 2 administrations. Detomidine i.v. is more widely distributed when administered to horses immediately after exercise compared to administration at rest resulting in lower peak plasma concentrations and a slower rate of elimination. The dose requirement to produce an equivalent effect may be higher in horses after exercise than in resting horses and less frequent subsequent doses may be required to produce a sustained effect.

  13. Maximal Bell's inequality violation for non-maximal entanglement

    International Nuclear Information System (INIS)

    Kobayashi, M.; Khanna, F.; Mann, A.; Revzen, M.; Santana, A.

    2004-01-01

    Bell's inequality violation (BIQV) for correlations of polarization is studied for a product state of two two-mode squeezed vacuum (TMSV) states. The violation allowed is shown to attain its maximal limit for all values of the squeezing parameter, ζ. We show via an explicit example that a state whose entanglement is not maximal allow maximal BIQV. The Wigner function of the state is non-negative and the average value of either polarization is nil

  14. Pharmacokinetic monitoring and dose modification of etanidazole in the RTOG 85-27 phase III head and neck trial

    International Nuclear Information System (INIS)

    Riese, Nancy E.; Buswell, Lori; Noll, Lisa; Pajak, Thomas F.; Stetz, JoAnn; Lee, D.J.; Coleman, C. Norman

    1997-01-01

    Purpose: To prospectively evaluate the pharmacokinetic monitoring and drug dose adjustment of Etanidazole (Eta) in patients treated on the RTOG randomized trial for Stage III and IV head and neck cancer. Methods and Materials: From June, 1986 to October, 1991, 521 patients were randomized to conventional RT alone or RT plus Eta. The primary goal was to determine whether the addition of Eta to conventional radiation therapy improves local-regional control and tumor-free survival. Of the 264 patients who received Eta, 233 had their drug exposure calculated and the Eta dose and schedule adjusted accordingly to prevent the occurrence of serious peripheral neuropathy. Drug exposure was assessed using the area under the curve (AUC) for a single treatment that was calculated by the integral over time of the serum concentration of Eta. The total drug exposure (total-AUC) was estimated by multiplying the AUC by the number of drug administrations. Results: Eighteen percent of patients developed Grade I and 6% developed Grade II peripheral neuropathy. There was no Grade 3 or 4 peripheral neuropathy. There is a trend for an increased risk of neuropathy by single dose AUC. The minimal difference in incidence of neuropathy by single-dose AUC was due to the use of dose and schedule modification for patients with the higher values. Conclusions: The pharmacokinetics investigated in this study confirm previous work that monitoring Eta levels, with dose adjustment, allows it to be used safely in the clinic. In a subset analysis there was a statistically significant improvement in local-regional control and survival rates for patients with N0 and N1 disease, that will require confirmation (14). However, the clinical efficacy of Eta in this trial proved to be of little overall benefit

  15. Influence of low- and high-dose radioiodine therapy on oxidative modification of fibrinogen

    International Nuclear Information System (INIS)

    Schweeger-Exeli, I.J.

    2001-10-01

    levels were significantly elevated above 300 mg/dl (p 0.05) and did not change to a significant extent after treatment in both subgroups. Conclusion: Purification of fibrinogen out of small volumes of plasma is feasible in a short period of time and requires only little technical effort. High - dose radioiodine therapy, applied in differentiated thyroid cancer, leads to significantly increased incorporation of carbonyl groups into the fibrinogen molecule. It remains to be elucidated, whether thyroid hormone status itself influences oxidative damage of fibrinogen. Key words: fibrinogen; radioiodine therapy; oxidative modification; isolation techniques; 2,4-dinitrophenylhydrazine. (author)

  16. Maximizing and customer loyalty: Are maximizers less loyal?

    Directory of Open Access Journals (Sweden)

    Linda Lai

    2011-06-01

    Full Text Available Despite their efforts to choose the best of all available solutions, maximizers seem to be more inclined than satisficers to regret their choices and to experience post-decisional dissonance. Maximizers may therefore be expected to change their decisions more frequently and hence exhibit lower customer loyalty to providers of products and services compared to satisficers. Findings from the study reported here (N = 1978 support this prediction. Maximizers reported significantly higher intentions to switch to another service provider (television provider than satisficers. Maximizers' intentions to switch appear to be intensified and mediated by higher proneness to regret, increased desire to discuss relevant choices with others, higher levels of perceived knowledge of alternatives, and higher ego involvement in the end product, compared to satisficers. Opportunities for future research are suggested.

  17. Risk of low-doses in radiodiagnosis; Risque des faibles doses en radiodiagnostic. Mythes, reglementation et rationalite

    Energy Technology Data Exchange (ETDEWEB)

    Cordoliani, Y.S.; Sarrazin, J.L.; Le Frian, G.; Soulie, D.; Leveque, C. [Hopital d`Instruction des Armees du Val-de-Grace, 75 - Paris (France)

    1997-12-31

    The effect of low doses of X-rays is inferred from the indubitable effects of high doses in human carcinogenesis, Genetic and teratogenic effects are mainly inferred from animal experimentation because clinical surveys of irradiated pregnant women have failed to demonstrate such consequences in the children, except for mental retardation after Japanese atomic bombing. Since no evidence of carcinogenic effect has been produced by epidemiological studies for doses lower than 500 mSv. the estimation of the risk due to low doses has been extrapolated from the linear relation between dose and cancers at high doses. Such an extrapolation gives a maximal risk which is falsely used as a probability of cancer. The actual risk lies between zero and this maximal number, and many epidemiologic surveys in people receiving doses much higher than the mean level of background irradiation failed to demonstrate higher rate of cancer. The explanation of this fact, which is supported by the most recent biological data, is the efficacy of the DNA repair system at low level of exposure to ionizing radiations. We expose the principles of regulation of radioprotection for workers, and give estimations of the doses delivered to the patients and the personnel by diagnostic investigations, by comparing these doses with those of natural irradiation. Practical aspect for conventional and computed radiology are exposed for patients and workers. (authors)

  18. 3D in radiotherapy - pushing the dose envelope to improve cure

    International Nuclear Information System (INIS)

    Leibel, Steven A.

    1996-01-01

    Approximately one in four newly diagnosed cancer patients receive radiation in the initial attempt to cure the tumor. In terms of the 1996 cancer incidence data, this comprises more than 350,000 patients. Inasmuch as 25% of these patients initially relapse at primary tumor sites, the issue of improving local control remains a major challenge to the profession. Recent improvements in treatment planning and delivery have enhanced the precision of radiotherapy, but radiation resistance remains a critical issue that confounds the potential for cure in many tumors. Chemical and biological modifiers of the radiation response have provided an approach with clinical promise, but their therapeutic impact remains to be established. Hence, tumor dose escalation continues to represent the most viable approach to improve local control. Recent experience with new conformal radiotherapy techniques has demonstrated that significant tumor dose escalation is feasible with concomitant reduction in normal tissue toxicity. This experience provides the best hope for immediate improvement in the rates of local tumor control. It remains, nonetheless, unclear how far the dose envelope can be pushed and whether this would be sufficient to overcome the problem of local failure. It may turn out that biological modification of the radiation response may still be necessary to provide a maximal control in certain types of tumors

  19. Introduction to the new version of the standard DIN 6814, part 3 'dose magnitudes and dose units'

    Energy Technology Data Exchange (ETDEWEB)

    Harder, D

    1985-02-01

    The recent draft of the DIN standard on dose quantities and dose units is presented on original version and explained by the chairman of the Working Comittee Dosimetry. There are important modifications by the introduction of SI units, the new definitions of site dose and individual dose characteristic dose rate and dose rate constant, as well as by corrections of the notions ''secondary electron equilibrium'' and ''free in air''.

  20. Simultaneous adjuvant radiation therapy and chemotherapy in high-risk breast cancer--toxicity and dose modification: a trans-tasman radiation oncology group multi-institution study

    International Nuclear Information System (INIS)

    Denham, James W.; Hamilton, Christopher S.; Christie, David; O'Brien, Maree; Bonaventura, Antonino; Stewart, John F.; Ackland, Stephen P.; Lamb, David S.; Spry, Nigel A.; Dady, Peter; Atkinson, Christopher H.; Wynne, Christopher; Joseph, David J.

    1995-01-01

    Purpose: To establish the toxicity profile of simultaneously administered postoperative radiation therapy and CMF chemotherapy as a prelude to a randomized controlled study addressing the sequencing of the two modalities. Methods and Materials: One hundred and thirty eight breast cancer patients at high risk of locoregional, as well as systemic relapse, who were referred to three centers in Australia and New Zealand were treated with postoperative radiation therapy and chemotherapy simultaneously. Acute toxicity and dose modifications in these patients were compared with 83 patients treated over the same time frame with chemotherapy alone. In a separate study the long-term radiation and surgical effects in 24 patients treated simultaneously with radiation therapy and chemotherapy at Newcastle (Australia) following conservative surgery were compared with 23 matched patients treated at Newcastle with radiation therapy alone. Results: Myelotoxicity was increased in patients treated simultaneously with radiation therapy and chemotherapy. The effect was not great, but may have contributed to chemotherapy dose reductions. Lymphopenia was observed to be the largest factor in total white cell depressions caused by the simultaneous administration of radiation therapy. Postsurgical appearances were found to so dominate long-term treatment effects on the treated breast that the effect of radiation therapy dose and additional chemotherapy was difficult to detect. Conclusion: Studies addressing the sequencing of radiation therapy and chemotherapy will necessarily be large because adverse effects from administering the two modalities simultaneously are not great. The present study has endorsed the importance in future studies of stratification according to the extent and type of surgery and adherence to a single strict policy of chemotherapy dose modification

  1. Hanford Dose Overview Program. Comparison of AIRDOS-EPA and Hanford site dose codes

    International Nuclear Information System (INIS)

    Aaberg, R.L.; Napier, B.A.

    1985-11-01

    Radiation dose commitments for persons in the Hanford environs calculated using AIRDOS-EPA were compared with those calculated using a suite of Hanford codes: FOOD, PABLM, DACRIN, and KRONIC. Dose commitments to the population and to the maximally exposed individual (MI) based on annual releases of eight radionuclides from the N-Reactor, were calculated by these codes. Dose commitments from each pathway to the total body, lung, thyroid, and lower large intestine (LLI) are given for the population and MI, respectively. 11 refs., 25 tabs

  2. EMP Attachment 3 DOE-SC PNNL Site Dose Assessment Guidance

    Energy Technology Data Exchange (ETDEWEB)

    Snyder, Sandra F.

    2011-12-21

    This Dose Assessment Guidance (DAG) describes methods to use to determine the Maximally-Exposed Individual (MEI) location and to estimate dose impact to that individual under the U.S. Department of Energy Office of Science (DOE-SC) Pacific Northwest National Laboratory (PNNL) Site Environmental Monitoring Plan (EMP). This guidance applies to public dose from radioactive material releases to the air from PNNL Site operations. This document is an attachment to the Pacific Northwest National Laboratory (PNNL) Environmental Monitoring Plan (EMP) and describes dose assessment guidance for radiological air emissions. The impact of radiological air emissions from the U.S. Department of Energy Office of Science (DOE-SC) PNNL Site is indicated by dose estimates to a maximally exposed member of the public, referred to as the maximally exposed individual (MEI). Reporting requirements associated with dose to members of the public from radiological air emissions are in 40 CFR Part 61.94, WAC 246-247-080, and DOE Order 458.1. The DOE Order and state standards for dose from radioactive air emissions are consistent with U.S. Environmental Protection Agency (EPA) dose standards in 40 CFR 61.92 (i.e., 10 mrem/yr to a MEI). Despite the fact that the current Contract Requirements Document (CRD) for the DOE-SC PNNL Site operations does not include the requirement to meet DOE CRD 458.1, paragraph 2.b, public dose limits, the DOE dose limits would be met when EPA limits are met.

  3. Post-closure radiation dose assessment for Yucca Mountain repository

    International Nuclear Information System (INIS)

    Jia Mingyan; Zhang Xiabin; Yang Chuncai

    2006-01-01

    A brief introduction of post-closure long-term radiation safety assessment results was represented for the yucca mountain high-level waste geographic disposal repository. In 1 million years after repository closure, for the higher temperature repository operating mode, the peak annual dose would be 150 millirem (120 millirem under the lower-temperature operating mode) to a reasonably maximally exposed individual approximately 18 kilometers (11 miles) from the repository. The analysis of a drilling intrusion event occurring at 30,000 years indicated a peak of the mean annual dose to the reasonably maximally exposed individual approximately 18 kilometers (11 miles) downstream of the repository would be 0.002 millirem. The analysis of an igneous activity scenario, including a volcanic eruption event and igneous intrusion event indicated a peak of the mean annual dose to the reasonably maximally exposed individual approximately 18 kilometers downstream of the repository would be 0.1 millirem. (authors)

  4. Tropism-Modification Strategies for Targeted Gene Delivery Using Adenoviral Vectors

    Directory of Open Access Journals (Sweden)

    Andrew H. Baker

    2010-10-01

    Full Text Available Achieving high efficiency, targeted gene delivery with adenoviral vectors is a long-standing goal in the field of clinical gene therapy. To achieve this, platform vectors must combine efficient retargeting strategies with detargeting modifications to ablate native receptor binding (i.e. CAR/integrins/heparan sulfate proteoglycans and “bridging” interactions. “Bridging” interactions refer to coagulation factor binding, namely coagulation factor X (FX, which bridges hepatocyte transduction in vivo through engagement with surface expressed heparan sulfate proteoglycans (HSPGs. These interactions can contribute to the off-target sequestration of Ad5 in the liver and its characteristic dose-limiting hepatotoxicity, thereby significantly limiting the in vivo targeting efficiency and clinical potential of Ad5-based therapeutics. To date, various approaches to retargeting adenoviruses (Ad have been described. These include genetic modification strategies to incorporate peptide ligands (within fiber knob domain, fiber shaft, penton base, pIX or hexon, pseudotyping of capsid proteins to include whole fiber substitutions or fiber knob chimeras, pseudotyping with non-human Ad species or with capsid proteins derived from other viral families, hexon hypervariable region (HVR substitutions and adapter-based conjugation/crosslinking of scFv, growth factors or monoclonal antibodies directed against surface-expressed target antigens. In order to maximize retargeting, strategies which permit detargeting from undesirable interactions between the Ad capsid and components of the circulatory system (e.g. coagulation factors, erythrocytes, pre-existing neutralizing antibodies, can be employed simultaneously. Detargeting can be achieved by genetic ablation of native receptor-binding determinants, ablation of “bridging interactions” such as those which occur between the hexon of Ad5 and coagulation factor X (FX, or alternatively, through the use of polymer

  5. Principles of maximally classical and maximally realistic quantum ...

    Indian Academy of Sciences (India)

    Principles of maximally classical and maximally realistic quantum mechanics. S M ROY. Tata Institute of Fundamental Research, Homi Bhabha Road, Mumbai 400 005, India. Abstract. Recently Auberson, Mahoux, Roy and Singh have proved a long standing conjecture of Roy and Singh: In 2N-dimensional phase space, ...

  6. Profit maximization mitigates competition

    DEFF Research Database (Denmark)

    Dierker, Egbert; Grodal, Birgit

    1996-01-01

    We consider oligopolistic markets in which the notion of shareholders' utility is well-defined and compare the Bertrand-Nash equilibria in case of utility maximization with those under the usual profit maximization hypothesis. Our main result states that profit maximization leads to less price...... competition than utility maximization. Since profit maximization tends to raise prices, it may be regarded as beneficial for the owners as a whole. Moreover, if profit maximization is a good proxy for utility maximization, then there is no need for a general equilibrium analysis that takes the distribution...... of profits among consumers fully into account and partial equilibrium analysis suffices...

  7. Implications of maximal Jarlskog invariant and maximal CP violation

    International Nuclear Information System (INIS)

    Rodriguez-Jauregui, E.; Universidad Nacional Autonoma de Mexico

    2001-04-01

    We argue here why CP violating phase Φ in the quark mixing matrix is maximal, that is, Φ=90 . In the Standard Model CP violation is related to the Jarlskog invariant J, which can be obtained from non commuting Hermitian mass matrices. In this article we derive the conditions to have Hermitian mass matrices which give maximal Jarlskog invariant J and maximal CP violating phase Φ. We find that all squared moduli of the quark mixing elements have a singular point when the CP violation phase Φ takes the value Φ=90 . This special feature of the Jarlskog invariant J and the quark mixing matrix is a clear and precise indication that CP violating Phase Φ is maximal in order to let nature treat democratically all of the quark mixing matrix moduli. (orig.)

  8. Identification of cofactor and herbicide binding domains in acetolactate synthase by bromopyruvate modification

    International Nuclear Information System (INIS)

    Van Dyk, D.E.; Schloss, J.V.

    1987-01-01

    Bromopyruvate is an affinity label for acetolactate synthase isozyme II from Salmonella typhimurium (ALSII). The concentration of bromopyruvate giving half-maximal inactivation is 0.1 mM, and the maximal rate of inactivation is 0.56 hr -1 . Inactivation with [ 14 C]bromopyruvate is associated with the incorporation of 4 molecules of reagent per active site lost. Two cysteinyl residues are modified extremely rapidly, with no loss of enzymatic activity, as judged by quenching the reaction with thiol after its initial phase. Inactivation is a consequence of the additional two moles of reagent incorporated per mole of protomer. The additional incorporation is divided between one major and two minor sites of modification. Substantial protection against inactivation is afforded by FAD, with virtually complete protection provided by a mixture of FAD and thiamine pyrophosphate (TPP). The major site of modification, protected by FAD, is cysteinyl residue number67, based upon amino acid sequence analysis of the purified tryptic peptide that encompasses this site. The remaining site of modification, protected by TPP, is associated with cysteinyl residue number44. Both sites of modification are afforded protection by the sulfonylurea herbicide sulfometuron methyl (SM). Although inactivation by bromopyruvate exhibits rate saturation, indicating binding as a prerequisite to inactivation, neither pyruvate nor α-ketobutyrate prevent modification of the enzyme by bromopyruvate. Thus, it would appear that the bromopyruvate binding site is not the site normally occupied by substrate

  9. Surface modification technique of structural ceramics: ion implantation-assisted multi-arc ion plating

    International Nuclear Information System (INIS)

    Peng Zhijian; Miao Hezhuo; Si Wenjie; Qi Longhao; Li Wenzhi

    2003-01-01

    Through reviewing the advantages and disadvantages of the existed surface modification techniques, a new technique, ion implantation-assisted multi-arc ion plating, was proposed. Using the proposed technique, the surfaces of silicon nitride ceramics were modified by Ti ion implantation, and then three kinds of ternary coatings, (Ti,Al)N, (Ti,Zr)N and (Ti,Cr)N, were deposited on the as-implanted ceramics. The coatings prepared by this technique are of high-hardness and well adhesive to the ceramic substrates. The maximal hardness measured by nanoindentation tests is more than 40 GPa. The maximal critical load by nanoscratch tests is more than 60 mN. The cutting tools prepared by this technique with the presented coatings are of excellent performance in industrial applications. The technique may be promising for the surface modification of structural ceramics. (orig.)

  10. Maximizers versus satisficers

    Directory of Open Access Journals (Sweden)

    Andrew M. Parker

    2007-12-01

    Full Text Available Our previous research suggests that people reporting a stronger desire to maximize obtain worse life outcomes (Bruine de Bruin et al., 2007. Here, we examine whether this finding may be explained by the decision-making styles of self-reported maximizers. Expanding on Schwartz et al. (2002, we find that self-reported maximizers are more likely to show problematic decision-making styles, as evidenced by self-reports of less behavioral coping, greater dependence on others when making decisions, more avoidance of decision making, and greater tendency to experience regret. Contrary to predictions, self-reported maximizers were more likely to report spontaneous decision making. However, the relationship between self-reported maximizing and worse life outcomes is largely unaffected by controls for measures of other decision-making styles, decision-making competence, and demographic variables.

  11. Nickel-sulphate-induced contact dermatitis in the guinea pig maximization test

    DEFF Research Database (Denmark)

    Rohold, A E; Nielsen, G D; Andersen, Klaus Ejner

    1991-01-01

    Nickel sulphate is a sensitizer in guinea pigs, but the frequency of sensitization varies from study to study. The dose-response relationship for NiSO4.6H2O was evaluated in the guinea pig maximization test in this study. 6 intradermal (0.01%-3.0% aq.) and 6 topical (0.25%-10.0% pet.) concentrati...

  12. Dose rate analysis for Tank 101 AZ (Project W151)

    International Nuclear Information System (INIS)

    Schwarz, R.A.; Hillesland, K.E.; Carter, L.L.

    1994-11-01

    This document describes the expected dose rates for modification to tank 101 AZ including modifications to the steam coil, mixer pump, and temperature probes. The thrust of the effort is to determine dose rates from: modification of a steam coil and caisson; the installation of mixer pumps; the installation of temperature probes; and estimates of dose rates that will be encountered while making these changes. Because the dose rates for all of these configurations depend upon the photon source within the supernate and sludge, comparisons were also made between measured dose rates within a drywell and the corresponding calculated dose rates. The calculational tool used is a Monte Carlo (MCNP 2 ) code since complicated three dimensional geometries are involved. A summary of the most important results of the entire study is given in Section 2. The basic calculational geometry model of the tank is discussed in Section 3, along with a tabulation of the photon sources that were used within the supernate and the sludge, and a discussion of uncertainties. The calculated dose rates around the steam coil and caisson before and after modification are discussed in Section 4. The configuration for the installation of the mixer pumps and the resulting dose rates are given in Section 5. The predicted changes in dose rates due to a possible dilution of the supernate source are given in Section 6. The calculational configuration used to model the installation of temperature probes and the resulting predicted dose rates are discussed in Section 7. Finally, comparisons of measured to calculated dose rates within a drywell are summarized in Section 8. Extended discussions of calculational models and Monte Carlo optimization techniques used are included in Appendix A

  13. Modifications of radiation detection response of PADC track detectors by photons

    CERN Document Server

    Sinha, D

    1998-01-01

    Photon induced modifications in polyalyldiglycol carbonate (PADC) track detectors have been studied in the dose range of 10 sup 1 -10 sup 6 Gy. It was found that some of the properties like bulk-etch rate, track-etch rate got enhanced at the dose of 10 sup 6 Gy. Activation energy for bulk-etching has been determined for different gamma doses. In order to correlate the high etch rate with the chemical modifications, UV-Vis, IR and ESR studies were carried out. These studies clearly give the indication that radiation damage results into radical formation through bond cleavage. TGA study was performed for understanding the thermal resistance of this detector. The results are presented and discussed.

  14. Using Microsoft Excel to compute the 5% overall site X/Q value and the 95th percentile of the distribution of doses to the nearest maximally exposed offsite individual (MEOI).

    Science.gov (United States)

    Vickers, Linda D

    2010-05-01

    This paper describes the method using Microsoft Excel (Microsoft Corporation One Microsoft Way Redmond, WA 98052-6399) to compute the 5% overall site X/Q value and the 95th percentile of the distribution of doses to the nearest maximally exposed offsite individual (MEOI) in accordance with guidance from DOE-STD-3009-1994 and U.S. NRC Regulatory Guide 1.145-1982. The accurate determination of the 5% overall site X/Q value is the most important factor in the computation of the 95th percentile of the distribution of doses to the nearest MEOI. This method should be used to validate software codes that compute the X/Q. The 95th percentile of the distribution of doses to the nearest MEOI must be compared to the U.S. DOE Evaluation Guide of 25 rem to determine the relative severity of hazard to the public from a postulated, unmitigated design basis accident that involves an offsite release of radioactive material.

  15. Developing maximal neuromuscular power: Part 1--biological basis of maximal power production.

    Science.gov (United States)

    Cormie, Prue; McGuigan, Michael R; Newton, Robert U

    2011-01-01

    This series of reviews focuses on the most important neuromuscular function in many sport performances, the ability to generate maximal muscular power. Part 1 focuses on the factors that affect maximal power production, while part 2, which will follow in a forthcoming edition of Sports Medicine, explores the practical application of these findings by reviewing the scientific literature relevant to the development of training programmes that most effectively enhance maximal power production. The ability of the neuromuscular system to generate maximal power is affected by a range of interrelated factors. Maximal muscular power is defined and limited by the force-velocity relationship and affected by the length-tension relationship. The ability to generate maximal power is influenced by the type of muscle action involved and, in particular, the time available to develop force, storage and utilization of elastic energy, interactions of contractile and elastic elements, potentiation of contractile and elastic filaments as well as stretch reflexes. Furthermore, maximal power production is influenced by morphological factors including fibre type contribution to whole muscle area, muscle architectural features and tendon properties as well as neural factors including motor unit recruitment, firing frequency, synchronization and inter-muscular coordination. In addition, acute changes in the muscle environment (i.e. alterations resulting from fatigue, changes in hormone milieu and muscle temperature) impact the ability to generate maximal power. Resistance training has been shown to impact each of these neuromuscular factors in quite specific ways. Therefore, an understanding of the biological basis of maximal power production is essential for developing training programmes that effectively enhance maximal power production in the human.

  16. Electron beam induced modification of grafted polyamides

    International Nuclear Information System (INIS)

    Timus, D.M.; Brasoveanu, M.M.; Bradley, D.A.; Popov, A.M.

    1998-01-01

    It is well known that irradiation, when applied on its own or in combination with other physical and chemical treatments, can manifest in radiation damage to materials. Radiation processing technology focuses upon producing favourable modification of materials through use of relatively high dose and dose rates. Current interest is in modifying the thermal and electrical properties of textured polymers in an effort to improve safety and wear comfort of clothing. No less important is the production of textiles which are safe to use, both in homes and offices. Present investigations provide additional data in support of findings which show that polyamides, a particular class of textured polymer, are amenable to radiation processing. Accelerated electron beam irradiation of sheets of polyamide fibre results in induced grafting of acrylic and methacrylic acids. The degree of grafting is critically dependent upon irradiation dose and the extent of monomers dilution. Of particular importance is the high correlation which is found between degree of grafting and a decrease in the softening rate of the modified polyamide. A systematic modification of electrical conductivity is also observed. (author)

  17. Structural modifications of swift heavy ion irradiated PEN probed by optical and thermal measurements

    International Nuclear Information System (INIS)

    Devgan, Kusum; Singh, Lakhwant; Samra, Kawaljeet Singh

    2013-01-01

    Highlights: • The present paper reports the effect of swift heavy ion irradiation on Polyethylene Naphthalate (PEN). • Swift heavy ion irradiation introduces structural modification and degradation of PEN at different doses. • Lower irradiation doses in PEN result in modification of structural properties and higher doses lead to complete degradation. • Strong correlation between structural, optical, and thermal properties. - Abstract: The effects of swift heavy ion irradiation on the structural characteristics of Polyethylene naphthalate (PEN) were studied. Samples were irradiated in vacuum at room temperature by lithium (50 MeV), carbon (85 MeV), nickel (120 MeV) and silver (120 MeV) ions with the fluence in the range of 1×10 11 –3×10 12 ions cm −2 . Ion induced changes were analyzed using X-ray diffraction (XRD), Fourier transform infra red (FT-IR), UV–visible spectroscopy, thermo-gravimetric analysis (TGA) and differential scanning calorimetry (DSC) techniques. Cross-linking was observed at lower doses resulting in modification of structural properties, however higher doses lead to the degradation of the investigated polymeric samples

  18. Impact of Dose to the Bladder Trigone on Long-Term Urinary Function After High-Dose Intensity Modulated Radiation Therapy for Localized Prostate Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Ghadjar, Pirus; Zelefsky, Michael J.; Spratt, Daniel E. [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Munck af Rosenschöld, Per; Oh, Jung Hun; Hunt, Margie [Department of Medical Physics, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Kollmeier, Marisa [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Happersett, Laura; Yorke, Ellen; Deasy, Joseph O. [Department of Medical Physics, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Jackson, Andrew, E-mail: jacksona@mskcc.org [Department of Medical Physics, Memorial Sloan-Kettering Cancer Center, New York, New York (United States)

    2014-02-01

    Purpose: To determine the potential association between genitourinary (GU) toxicity and planning dose–volume parameters for GU pelvic structures after high-dose intensity modulated radiation therapy in localized prostate cancer patients. Methods and Materials: A total of 268 patients who underwent intensity modulated radiation therapy to a prescribed dose of 86.4 Gy in 48 fractions during June 2004-December 2008 were evaluated with the International Prostate Symptom Score (IPSS) questionnaire. Dose–volume histograms of the whole bladder, bladder wall, urethra, and bladder trigone were analyzed. The primary endpoint for GU toxicity was an IPSS sum increase ≥10 points over baseline. Univariate and multivariate analyses were done by the Kaplan-Meier method and Cox proportional hazard models, respectively. Results: Median follow-up was 5 years (range, 3-7.7 years). Thirty-nine patients experienced an IPSS sum increase ≥10 during follow-up; 84% remained event free at 5 years. After univariate analysis, lower baseline IPSS sum (P=.006), the V90 of the trigone (P=.006), and the maximal dose to the trigone (P=.003) were significantly associated with an IPSS sum increase ≥10. After multivariate analysis, lower baseline IPSS sum (P=.009) and increased maximal dose to the trigone (P=.005) remained significantly associated. Seventy-two patients had both a lower baseline IPSS sum and a higher maximal dose to the trigone and were defined as high risk, and 68 patients had both a higher baseline IPSS sum and a lower maximal dose to the trigone and were defined as low risk for development of an IPSS sum increase ≥10. Twenty-one of 72 high-risk patients (29%) and 5 of 68 low-risk patients (7%) experienced an IPSS sum increase ≥10 (P=.001; odds ratio 5.19). Conclusions: The application of hot spots to the bladder trigone was significantly associated with relevant changes in IPSS during follow-up. Reduction of radiation dose to the lower bladder and specifically the

  19. Determination of organ doses during radiological examinations and calculation of somatically significant dose

    International Nuclear Information System (INIS)

    Steiner, H.

    1980-01-01

    Examples are used to demonstrate that a shift in the point of emphasis is necessary with regard to radiation hazard in medicinal X-ray diagnosis. The parameters employed in this study to calculate somatic dose (SD) and somatically significant dose (SSD) may well be in need of modification; nevertheless the numerical estimation of SSD arrived at here appears to reflect the right order of magnitude for the estimation of somatic risk. The consideration of the threshold dose for somatic injury remains a problem. (orig./MG) [de

  20. Patient doses in interventional cardiology procedures

    International Nuclear Information System (INIS)

    Domienik, J.; Papierz, S.; Jankowski, J.; Peruga, J.Z.

    2008-01-01

    In most countries of European Union legislation requires the determination of the total skin dose to patient resulting from interventional procedures to assess the risk of deterministic effect. To this end, various dose indicators like dose area product (DAP), cumulative dose (CD) and entrance dose at the patient plane (EFD) are used in clinical practice. The study aims at relating those dose indicators with doses ascribe to the most irradiated areas of the patient skin usually expressed in terms of local maximal skin dose (MSD). For the study the local MSD and related to their areas are investigated and compared for coronary angiography CA and intervention (PCI). Two methods implying radiographic films Kodak EDR2 and matrixes of thermoluminescent dosimeters (TLDs) are applied for direct measurements of dose distribution for selected procedures. Both methods are compared. Additionally, for patient dosimetry the following data: MSD, CD, EFD, fluoroscopy time (FT), number of acquired images, total DAP, fluoro-DAP and record-DAP were collected for randomly selected procedure. The statistical quantities like: median, 3 rd quartile, mean and standard deviation for all dosimetric parameters are determined. Preliminary study showed that the values of data collected for coronary procedures are in the ranges 0,7 - 27,3 min for fluoroscopy time, 50 - 350 Gy cm 2 for total DAP, 300 - 2000 mGy for CD, 140 - 2000 mGy for EFD and 100 - 1500 mGy for local maximal skin dose. For interventions the ranges are, accordingly 3,0 - 43,6 min , 25 - 450 Gy cm 2 , 270 - 6600 mGy, 80 - 2600 mGy and 80 - 1500 mGy. As a result of the study the correlations between dose indicators and local MSD are analyzed. The concentration of dose on irradiated films are going to be investigated in some detail as well. (author)

  1. Maximizers versus satisficers

    OpenAIRE

    Andrew M. Parker; Wandi Bruine de Bruin; Baruch Fischhoff

    2007-01-01

    Our previous research suggests that people reporting a stronger desire to maximize obtain worse life outcomes (Bruine de Bruin et al., 2007). Here, we examine whether this finding may be explained by the decision-making styles of self-reported maximizers. Expanding on Schwartz et al. (2002), we find that self-reported maximizers are more likely to show problematic decision-making styles, as evidenced by self-reports of less behavioral coping, greater dependence on others when making decisions...

  2. Dose measurement of ion implanted silicon by RBS technique

    International Nuclear Information System (INIS)

    Kamawanna, Teerasak; Intarasiri, Saweat; Prapunsri, Chowunchun; Thongleurm, Chome; Maleepatra, Saenee; Singkarat, Somsorn

    2003-10-01

    Surface modification can be achieved by ion implantation. This study used a 1 mm thick silicon wafer as a target which was implanted with Ar+ at 80 keV. The degree of the modification depends on both the ion energy and the implanted dose. The distribution of argon in the silicon substrate and the absolute implanted dose can be measured by using Rutherford Backscattering Spectrometry (RBS). These investigations utilized a 1.7 MV Tandetron accelerator system at Chiang Mai University. The dose determination by a direct calculation is in agreement with the simulation by the SIMNRA code

  3. Estimation of the fetal dose by dose measurement during an irradiation of a parotid tumor; Estimation de la dose foetale par mesure de dose lors d'une irradiation d'une tumeur de la parotide

    Energy Technology Data Exchange (ETDEWEB)

    Marchesi, V.; Graff-Cailleaud, P.; Peiffert, D. [Centre Alexis-Vautrin, 54 - Vandoeuvre-les-Nancy (France); Noel, A. [Institut National Polytechnique de Lorraine, CRAN CNRS UMR-7039, 54 - Vandoeuvre-les-Nancy (France)

    2006-11-15

    The irradiation of a five months pregnant patient has been made for a right parotid attack. In conformation with the legislative texts relative to radiation protection ( publication 84 of the ICRP) an estimation of the dose received for the fetus has been led by dose measurement on phantom. With the dose limit ( 100 mGy) recommended in the publication 84 of the ICRP neither modification of the treatment nor abortion was necessary. (N.C.)

  4. In vitro and in vivo effects of low dose HTO contamination modulated by dose rate

    International Nuclear Information System (INIS)

    Petcu, I.; Savu, D.; Moisoi, N.; Koeteles, G.J.

    1997-01-01

    The experiment performed in vitro intended to examine whether an adaptive response could be elicited on lymphocytes by low-level contamination of whole blood with tritiated water and if the modification of the dose rate has any influence on it. Lymphocytes pre-exposed to 3 HOH (0.2 - 6.6 MBq/ml) and subsequently irradiated with I Gy γ-rays showed micronuclei frequency significantly lower (40% - 45%) than the expected member (sum of the yields induced by 3 HOH and γ-rays separately). The degree of the radioresistance induced by HTO pre-treatments became higher with decreasing dose-rate for a rather similar total adapting dose. In vivo, the aim of the study was to investigate if different dose rates are inducing modulation of the lipid peroxidation level and of the thymidine uptake in different tissues of animals contaminated by HTO ingestion. The total doses varied between 5 and 20 cGy and were delivered as chronic (100 days) or acute contamination (5 days). It was observed that only doses about 20 cGy caused a dose-rate dependent increase of the lipid peroxidation level in the tissues of small intestine, kidney and spleen. Both chronic and acute contamination did produce reduced incorporation of thymidine in the cells of bone marrow. The most effective decrease of thymidine uptake was induced by the acute contamination in the lower dose domain (approx. 5 cGy). Our hypothesis is that in this dose domain the modification of thymidine uptake could be due to changes at the level of membrane transport. (author)

  5. Modifications in the optical and thermal properties of a CR-39 polymeric detector induced by high doses of γ-radiation

    Science.gov (United States)

    Saad, A. F.; Ibraheim, Mona H.; Nwara, Aya M.; Kandil, S. A.

    2018-04-01

    Effects of γ-radiation on the optical and thermal properties of a poly allyl diglycol carbonate (PADC), a form of CR-39, polymer have been investigated. CR-39 detectors were exposed to γ-rays at very high doses ranging from 5.0 × 105 to 3.0 × 106 Gy. The induced changes were analyzed using ultraviolet-visible spectroscopy (UV-VIS) in absorbance mode, and thermogravimetric analysis (TGA). The UV-visible spectra of the virgin and γ-irradiated CR-39 polymer detectors displayed a significant decreasing trend in their optical energy band gaps for indirect transitions, whereas for the direct ones showed a little change. This drop in the energy band gap with increasing dose is discussed on the basis of the gamma irradiation induced modifications in the CR-39 polymeric detector. The TGA thermograms show that the weight loss rate increased with increase in dose, which may be due to the disordered system via scission followed by crosslinking in the irradiated polymer detector. The TGA thermograms also indicated that the CR-39 detector decomposed in three/four stages for the virgin and irradiated samples. The activation energy for thermal decomposition was determined using a type of Arrhenius equation based on the TGA experimental results. These experimental results so obtained can be well used in radiation dosimetry.

  6. Mahalanobis distance and variable selection to optimize dose response

    International Nuclear Information System (INIS)

    Moore, D.H. II; Bennett, D.E.; Wyrobek, A.J.; Kranzler, D.

    1979-01-01

    A battery of statistical techniques are combined to improve detection of low-level dose response. First, Mahalanobis distances are used to classify objects as normal or abnormal. Then the proportion classified abnormal is regressed on dose. Finally, a subset of regressor variables is selected which maximizes the slope of the dose response line. Use of the techniques is illustrated by application to mouse sperm damaged by low doses of x-rays

  7. Kinetic and dose dependencies of the SOS-induction in E.coli K-12 (uvrA) cells exposed to different UV doses

    International Nuclear Information System (INIS)

    Komova, O.V.; Kandiano, E.S.; Malavina, G.; )

    2000-01-01

    Kinetic and dose dependencies of the SOS-induction in E. coli (uvrA) cells exposed to UV light were investigated. below 2 J/m 2 the rate of the SOS-induction increased with dose. Maximal level of the SOS-response was proportional to the UV dose. Pyrimidine dimers were necessary for the induction. In the dose range 2-10 J/m 2 the rate of SOS-induction decreased with dose. Dose-maximum response curve was non-linear. Pyrimidine dimers were not required for the induction. nature of the molecular events leading to the SOS-induction at low and high doses was discussed [ru

  8. Dose measurements in mammography

    International Nuclear Information System (INIS)

    Kainberger, F.; Kallinger, W.

    1977-01-01

    Dose measurements at the mamma during mammography were carried out in the form of direct measurement with thermoluminescent dosimetry. Measurement was done for the in- and outcoming doses at the mamma, the dose exposure of the sternal region and the scattered rays above the symphysis, the latter as parameter for the genetic radiation exposure. As expected, the dose of the smooth radiation used for mammography showed a strong decrease at the outcome point in comparison with the income point. Surprisingly high was the scattered radiation in the sternal region. A corresponding protection by lead plates could be taken into consideration. Extremely low is the scattered radiation above the symphysis. Even measurements with the very sensitive calcium fluoride dosimeters did not reveal any practically important dose in the symphysis region. Most measurement values remained below the determinable dose of 0.3mR. Some maximal values varied in the range of 3-1 mR. (orig.) [de

  9. Increase in gas output by active modification of the water pressure regime

    Energy Technology Data Exchange (ETDEWEB)

    Zakirov, S N; Gordon, V Y; Kondrat, R M; Kravtsov, N A; Somov, B Y

    1981-01-01

    Based on gas-hydrodynamic calculations made on a planar model formation, two variants of formation working are examined. In the first variant, the modern ideology of working gas fields with a water pressure regime are simulated. In the second variant, working of the formation is modeled according to the suggested ideology of active modification of the water-pressure regime by operating the flooded gas wells. The calculations made indicate the efficiency of active modification of the water pressure regime from the viewpoint of controlling the fund of E wells, and most important, maximizing the final coefficient of gas bed output.

  10. Entropy maximization

    Indian Academy of Sciences (India)

    Abstract. It is shown that (i) every probability density is the unique maximizer of relative entropy in an appropriate class and (ii) in the class of all pdf f that satisfy. ∫ fhi dμ = λi for i = 1, 2,...,...k the maximizer of entropy is an f0 that is pro- portional to exp(. ∑ ci hi ) for some choice of ci . An extension of this to a continuum of.

  11. Entropy Maximization

    Indian Academy of Sciences (India)

    It is shown that (i) every probability density is the unique maximizer of relative entropy in an appropriate class and (ii) in the class of all pdf that satisfy ∫ f h i d = i for i = 1 , 2 , … , … k the maximizer of entropy is an f 0 that is proportional to exp ⁡ ( ∑ c i h i ) for some choice of c i . An extension of this to a continuum of ...

  12. Maximally incompatible quantum observables

    Energy Technology Data Exchange (ETDEWEB)

    Heinosaari, Teiko, E-mail: teiko.heinosaari@utu.fi [Turku Centre for Quantum Physics, Department of Physics and Astronomy, University of Turku, FI-20014 Turku (Finland); Schultz, Jussi, E-mail: jussi.schultz@gmail.com [Dipartimento di Matematica, Politecnico di Milano, Piazza Leonardo da Vinci 32, I-20133 Milano (Italy); Toigo, Alessandro, E-mail: alessandro.toigo@polimi.it [Dipartimento di Matematica, Politecnico di Milano, Piazza Leonardo da Vinci 32, I-20133 Milano (Italy); Istituto Nazionale di Fisica Nucleare, Sezione di Milano, Via Celoria 16, I-20133 Milano (Italy); Ziman, Mario, E-mail: ziman@savba.sk [RCQI, Institute of Physics, Slovak Academy of Sciences, Dúbravská cesta 9, 84511 Bratislava (Slovakia); Faculty of Informatics, Masaryk University, Botanická 68a, 60200 Brno (Czech Republic)

    2014-05-01

    The existence of maximally incompatible quantum observables in the sense of a minimal joint measurability region is investigated. Employing the universal quantum cloning device it is argued that only infinite dimensional quantum systems can accommodate maximal incompatibility. It is then shown that two of the most common pairs of complementary observables (position and momentum; number and phase) are maximally incompatible.

  13. Maximally incompatible quantum observables

    International Nuclear Information System (INIS)

    Heinosaari, Teiko; Schultz, Jussi; Toigo, Alessandro; Ziman, Mario

    2014-01-01

    The existence of maximally incompatible quantum observables in the sense of a minimal joint measurability region is investigated. Employing the universal quantum cloning device it is argued that only infinite dimensional quantum systems can accommodate maximal incompatibility. It is then shown that two of the most common pairs of complementary observables (position and momentum; number and phase) are maximally incompatible.

  14. A Numerical and Experimental Study of Ejector Internal Flow Structure and Geometry Modification for Maximized Performance

    Science.gov (United States)

    Falsafioon, Mehdi; Aidoun, Zine; Poirier, Michel

    2017-12-01

    A wide range of industrial refrigeration systems are good candidates to benefit from the cooling and refrigeration potential of supersonic ejectors. These are thermally activated and can use waste heat recovery from industrial processes where it is abundantly generated and rejected to the environment. In other circumstances low cost heat from biomass or solar energy may also be used in order to produce a cooling effect. Ejector performance is however typically modest and needs to be maximized in order to take full advantage of the simplicity and low cost of the technology. In the present work, the behavior of ejectors with different nozzle exit positions has been investigated using a prototype as well as a CFD model. The prototype was used in order to measure the performance advantages of refrigerant (R-134a) flowing inside the ejector. For the CFD model, it is assumed that the ejectors are axi-symmetric along x-axis, thus the generated model is in 2D. The preliminary CFD results are validated with experimental data over a wide range of conditions and are in good accordance in terms of entrainment and compression ratios. Next, the flow patterns of four different topologies are studied in order to discuss the optimum geometry in term of ejector entrainment improvement. Finally, The numerical simulations were used to find an optimum value corresponding to maximized entrainment ratio for fixed operating conditions.

  15. Chronic rectal bleeding after high dose conformal treatment of prostate cancer warrants modification of existing morbidity scales

    International Nuclear Information System (INIS)

    Hanlon, A.L.; Schulthiess, T.E.; Hunt, M.A.; Movsas, B.; Peter, R.; Hanks, G.E.

    1996-01-01

    Purpose: Serious late morbidity (Grade (3(4))) from the conformal treatment of prostate cancer has been reported in <1% to 6% of patients. This study demonstrates that the reported frequency of Grade (3(4)) complications varies by the morbidity scale selected and that no existing morbidity scale adequately represents chronic rectal bleeding, which is our most frequent persisting late sequela of high dose conformal treatment. Materials and Methods: Between (5(89)) and (12(93)), 352 patients with T1-3 NXM0 prostate cancers were treated with our 4-field conformal technique without special rectal blocking. This technique includes a 1 cm margin from the CTV to the PTV in all directions. The median follow-up for these patients was 38 mos (4 to 78), and the median ICRU reporting point dose was 74 Gy (63 to 81). Patients are followed at six month intervals, and no patient is lost to follow-up. Three morbidity scales are assessed, the RTOG, the late effects group (LENT), and our modification of the LENT (FC-LENT). This modification registers chronic rectal bleeding requiring more than two coagulations as a grade 3 event. Estimates for Grade (3(4)) late GI complication rates were determined using Kaplan-Meier methodology. Differences in morbidity rates were evaluated using the log-rank test and differences in time to latency of complications were evaluated using the nonparametric Wilcoxon test. The duration of severe symptoms with chronic rectal bleeding is measured from the first to the last transrectal coagulation. Results: Sixteen patients developed Grade (3(4)) complications by one of the three morbidity scales. Two patients required surgery (colostomy, sigmoid resection), 5 required a transfusion, and 9 required more than two coagulations. The median latency to the third coagulation (plus or minus transfusions) was 24 mos (17 to 40). The median duration of bleeding between the first and last coagulation was 6 mos (3 to 25), illustrating the chronicity of this problem

  16. Maximal combustion temperature estimation

    International Nuclear Information System (INIS)

    Golodova, E; Shchepakina, E

    2006-01-01

    This work is concerned with the phenomenon of delayed loss of stability and the estimation of the maximal temperature of safe combustion. Using the qualitative theory of singular perturbations and canard techniques we determine the maximal temperature on the trajectories located in the transition region between the slow combustion regime and the explosive one. This approach is used to estimate the maximal temperature of safe combustion in multi-phase combustion models

  17. Developing maximal neuromuscular power: part 2 - training considerations for improving maximal power production.

    Science.gov (United States)

    Cormie, Prue; McGuigan, Michael R; Newton, Robert U

    2011-02-01

    This series of reviews focuses on the most important neuromuscular function in many sport performances: the ability to generate maximal muscular power. Part 1, published in an earlier issue of Sports Medicine, focused on the factors that affect maximal power production while part 2 explores the practical application of these findings by reviewing the scientific literature relevant to the development of training programmes that most effectively enhance maximal power production. The ability to generate maximal power during complex motor skills is of paramount importance to successful athletic performance across many sports. A crucial issue faced by scientists and coaches is the development of effective and efficient training programmes that improve maximal power production in dynamic, multi-joint movements. Such training is referred to as 'power training' for the purposes of this review. Although further research is required in order to gain a deeper understanding of the optimal training techniques for maximizing power in complex, sports-specific movements and the precise mechanisms underlying adaptation, several key conclusions can be drawn from this review. First, a fundamental relationship exists between strength and power, which dictates that an individual cannot possess a high level of power without first being relatively strong. Thus, enhancing and maintaining maximal strength is essential when considering the long-term development of power. Second, consideration of movement pattern, load and velocity specificity is essential when designing power training programmes. Ballistic, plyometric and weightlifting exercises can be used effectively as primary exercises within a power training programme that enhances maximal power. The loads applied to these exercises will depend on the specific requirements of each particular sport and the type of movement being trained. The use of ballistic exercises with loads ranging from 0% to 50% of one-repetition maximum (1RM) and

  18. Kinetic and dose dependences of the SOS-induction in E.coli K-12 (uvrA) cells exposed to the different UV doses

    International Nuclear Information System (INIS)

    Komova, O.V.; Kandiano, E.S.; Malavya, G.

    1999-01-01

    The kinetic and dose dependences of the SOS-induction in E.coli (uvrA) cells exposed to UV light were investigated. Below 2 J/m 2 the rate of the SOS-induction increased with dose. The maximal level of the SOS-response was proportional to the UV dose. Pyrimidine dimers were necessary for the induction. In the dose range 2-10 J/m 2 the rate of the SOS-induction decreased with dose. The dose-response curve was non-linear. Pyrimidine dimers were not required for the induction. The nature of the molecular events leading to the SOS-induction at low and high UV doses was discussed. (author)

  19. Individualized Dose Prescription for Hypofractionation in Advanced Non-Small-Cell Lung Cancer Radiotherapy: An in silico Trial

    Energy Technology Data Exchange (ETDEWEB)

    Hoffmann, Aswin L.; Troost, Esther G.C.; Huizenga, Henk; Kaanders, Johannes H.A.M. [Radboud University Nijmegen Medical Centre, Department of Radiation Oncology, Nijmegen (Netherlands); Bussink, Johan, E-mail: j.bussink@rther.umcn.nl [Radboud University Nijmegen Medical Centre, Department of Radiation Oncology, Nijmegen (Netherlands)

    2012-08-01

    Purpose: Local tumor control and outcome remain poor in patients with advanced non-small-cell lung cancer (NSCLC) treated by external beam radiotherapy. We investigated the therapeutic gain of individualized dose prescription with dose escalation based on normal tissue dose constraints for various hypofractionation schemes delivered with intensity-modulated radiation therapy. Methods and Materials: For 38 Stage III NSCLC patients, the dose level of an existing curative treatment plan with standard fractionation (66 Gy) was rescaled based on dose constraints for the lung, spinal cord, esophagus, brachial plexus, and heart. The effect on tumor total dose (TTD) and biologic tumor effective dose in 2-Gy fractions (TED) corrected for overall treatment time (OTT) was compared for isotoxic and maximally tolerable schemes given in 15, 20, and 33 fractions. Rescaling was accomplished by altering the dose per fraction and/or the number of fractions while keeping the relative dose distribution of the original treatment plan. Results: For 30 of the 38 patients, dose escalation by individualized hypofractionation yielded therapeutic gain. For the maximally tolerable dose scheme in 33 fractions (MTD{sub 33}), individualized dose escalation resulted in a 2.5-21% gain in TTD. In the isotoxic schemes, the number of fractions could be reduced with a marginal increase in TED. For the maximally tolerable dose schemes, the TED could be escalated up to 36.6%, and for all patients beyond the level of the isotoxic and the MTD{sub 33} schemes (range, 3.3-36.6%). Reduction of the OTT contributed to the therapeutic gain of the shortened schemes. For the maximally tolerable schemes, the maximum esophageal dose was the dominant dose-limiting constraint in most patients. Conclusions: This modeling study showed that individualized dose prescription for hypofractionation in NSCLC radiotherapy, based on scaling of existing treatment plans up to normal tissue dose constraints, enables dose

  20. A study on mice exposure dose for low-dose gamma-irradiation using glass dosimeter

    Energy Technology Data Exchange (ETDEWEB)

    Noh, Sung Jin; Kim, Hyo Jin; Kim, Hyun; Jeong, Dong Hyeok; Son, Tae Gen; Kim, Jung Ki; Yang, Kwang Mo; Kang, Yeong Rok [Research Center, Dongnam Institute of Radiological and Medical Sciences, Busan (Korea, Republic of); Nam, Sang Hee [Dept. of Biomedical Engineering, Inje University, Gimhae (Korea, Republic of)

    2015-12-15

    The low dose radiation is done for a long period, thus researchers have to know the exact dose distribution for the irradiated mouse. This research has been conducted in order to find out methods in transmitting an exact dose to mouse in a mouse irradiation experiment carried out using {sup 137}C{sub s} irradiation equipment installed in the DIRAMS (Dongnam Institution of Radiological and Medical Sciences) research center. We developed a single mouse housing cage and shelf with adjustable geometric factors such as distance and angle from collimator. The measurement of irradiated dose showed a maximal 42% difference of absorbed dose from the desired dose in the conventional irradiation system, whereas only 6% difference of the absorbed dose was measured in the self-developed mouse apartment system. In addition, multi mice housing showed much difference of the absorbed dose in between head and body, compared to single mouse housing in the conventional irradiation system. This research may allow further research about biological effect assessment for the low dose irradiation using the self-developed mouse apartment to provide more exact doses which it tries to transmit, and to have more reliability for the biological analysis results.

  1. Calculation methods for determining dose equivalent

    International Nuclear Information System (INIS)

    Endres, G.W.R.; Tanner, J.E.; Scherpelz, R.I.; Hadlock, D.E.

    1987-11-01

    A series of calculations of neutron fluence as a function of energy in an anthropomorphic phantom was performed to develop a system for determining effective dose equivalent for external radiation sources. Critical organ dose equivalents are calculated and effective dose equivalents are determined using ICRP-26 [1] methods. Quality factors based on both present definitions and ICRP-40 definitions are used in the analysis. The results of these calculations are presented and discussed. The effective dose equivalent determined using ICRP-26 methods is significantly smaller than the dose equivalent determined by traditional methods. No existing personnel dosimeter or health physics instrument can determine effective dose equivalent. At the present time, the conversion of dosimeter response to dose equivalent is based on calculations for maximal or ''cap'' values using homogeneous spherical or cylindrical phantoms. The evaluated dose equivalent is, therefore, a poor approximation of the effective dose equivalent as defined by ICRP Publication 26. 3 refs., 2 figs., 1 tab

  2. Chronic rectal bleeding after high-dose conformal treatment of prostate cancer warrants modification of existing morbidity scales

    International Nuclear Information System (INIS)

    Hanlon, Alexandra L.; Schultheiss, Timothy E.; Hunt, Margie A.; Movsas, Benjamin; Peter, Ruth S.; Hanks, Gerald E.

    1997-01-01

    Purpose: Serious late morbidity (Grade (3(4))) from the conformal treatment of prostate cancer has been reported in <1% to 6% of patients based on existing late gastrointestinal (GI) morbidity scales. None of the existing morbidity scales include our most frequently observed late GI complication, which is chronic rectal bleeding requiring multiple fulgerations. This communication documents the frequency of rectal bleeding requiring multiple fulgerations and illustrates the variation in reported late serious GI complication rates by the selection of morbidity scale. Methods and Materials: Between May 1989 and December 1993, 352 patients with T1-T3 nonmetastatic prostate cancers were treated with our four-field conformal technique without special rectal blocking. This technique includes a 1-cm margin from the clinical target volume (CTV) to the planning target volume (PTV) in all directions. The median follow-up for these patients was 36 months (range 2-76), and the median center of prostate dose was 74 Gy (range 63-81). Three morbidity scales are assessed: the Radiation Therapy Oncology Group (RTOG), the Late Effects Normal Tissue Task Force (LENT), and our modification of the LENT (FC-LENT). This modification registers chronic rectal bleeding requiring at least one blood transfusion and/or more than two coagulations as a Grade 3 event. Estimates for Grade (3(4)) late GI complication rates were determined using Kaplan-Meier methodology. The duration of severe symptoms with chronic rectal bleeding is measured from the first to the last transrectal coagulation. Latency is measured from the end of radiotherapy to surgery, first blood transfusion, or third coagulation procedure. Results: Sixteen patients developed Grade (3(4)) complications by one of the three morbidity scales. Two patients required surgery (colostomy or sigmoid resection), three required multiple blood transfusions, two required one or two blood transfusions, and nine required at least three

  3. Association Between Maximal Skin Dose and Breast Brachytherapy Outcome: A Proposal for More Rigorous Dosimetric Constraints

    International Nuclear Information System (INIS)

    Cuttino, Laurie W.; Heffernan, Jill; Vera, Robyn; Rosu, Mihaela; Ramakrishnan, V. Ramesh; Arthur, Douglas W.

    2011-01-01

    Purpose: Multiple investigations have used the skin distance as a surrogate for the skin dose and have shown that distances 4.05 Gy/fraction. Conclusion: The initial skin dose recommendations have been based on safe use and the avoidance of significant toxicity. The results from the present study have suggested that patients might further benefit if more rigorous constraints were applied and if the skin dose were limited to 120% of the prescription dose.

  4. Expected treatment dose construction and adaptive inverse planning optimization: Implementation for offline head and neck cancer adaptive radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Yan Di; Liang Jian [Department of Radiation Oncology, Beaumont Health System, Royal Oak, Michigan 48073 (United States)

    2013-02-15

    Purpose: To construct expected treatment dose for adaptive inverse planning optimization, and evaluate it on head and neck (h and n) cancer adaptive treatment modification. Methods: Adaptive inverse planning engine was developed and integrated in our in-house adaptive treatment control system. The adaptive inverse planning engine includes an expected treatment dose constructed using the daily cone beam (CB) CT images in its objective and constrains. Feasibility of the adaptive inverse planning optimization was evaluated retrospectively using daily CBCT images obtained from the image guided IMRT treatment of 19 h and n cancer patients. Adaptive treatment modification strategies with respect to the time and the number of adaptive inverse planning optimization during the treatment course were evaluated using the cumulative treatment dose in organs of interest constructed using all daily CBCT images. Results: Expected treatment dose was constructed to include both the delivered dose, to date, and the estimated dose for the remaining treatment during the adaptive treatment course. It was used in treatment evaluation, as well as in constructing the objective and constraints for adaptive inverse planning optimization. The optimization engine is feasible to perform planning optimization based on preassigned treatment modification schedule. Compared to the conventional IMRT, the adaptive treatment for h and n cancer illustrated clear dose-volume improvement for all critical normal organs. The dose-volume reductions of right and left parotid glands, spine cord, brain stem and mandible were (17 {+-} 6)%, (14 {+-} 6)%, (11 {+-} 6)%, (12 {+-} 8)%, and (5 {+-} 3)% respectively with the single adaptive modification performed after the second treatment week; (24 {+-} 6)%, (22 {+-} 8)%, (21 {+-} 5)%, (19 {+-} 8)%, and (10 {+-} 6)% with three weekly modifications; and (28 {+-} 5)%, (25 {+-} 9)%, (26 {+-} 5)%, (24 {+-} 8)%, and (15 {+-} 9)% with five weekly modifications. Conclusions

  5. Influence of Polylactide Modification with Blowing Agents on Selected Mechanical Properties

    Directory of Open Access Journals (Sweden)

    Aneta Tor-Świątek

    2017-12-01

    Full Text Available Article presents research of modification of PLA with four types of chemical blowing agents with a different decomposition characteristic. The modification was done both cellular extrusion and injection molding processes. Obtained results shows that dosing blowing agents have the influence on mechanical properties and structure morphology of PLA. The differences in obtained results are also visible and significant between cellular processes.

  6. Dose-volume considerations in stereotaxic brain radiation therapy

    International Nuclear Information System (INIS)

    Houdek, P.V.; Schwade, J.G.; Pisciotta, V.J.; Medina, A.J.; Lewin, A.A.; Abitbol, A.A.; Serago, C.F.

    1988-01-01

    Although brain radiation therapy experience suggests that a gain in the therapeutic ratio may be achieved by optimizing the dose-volume relationship, no practical system for quantitative assessment of dose-volume data has been developed. This presentation describes the rationale for using the integral dose function for this purpose and demonstrates that with the use of a conventional treatment planning computer and a series of computed tomographic scans, first-order optimization of the dose-volume function can be accomplished in two steps: first, high-dose volume is minimized by selecting an appropriate treatment technique and tumor margin, and then dosage is maximized by calculating the brain tolerance dose as a function of the irradiated volume

  7. Electron beam modification of vanadium dioxide oscillators

    Energy Technology Data Exchange (ETDEWEB)

    Belyaev, Maksim; Velichko, Andrey; Putrolaynen, Vadim; Perminov, Valentin; Pergament, Alexander [Petrozavodsk State University, Petrozavodsk (Russian Federation)

    2017-03-15

    The paper presents the results of a study of electron-beam modification (EBM) of VO{sub 2}-switch I-V curve threshold parameters and the self-oscillation frequency of a circuit containing such a switching device. EBM in vacuum is reversible and the parameters are restored when exposed to air at pressure of 150 Pa. At EBM with a dose of 3 C cm{sup -2}, the voltages of switching-on (V{sub th}) and off (V{sub h}), as well as the OFF-state resistance R{sub off}, decrease down to 50% of the initial values, and the oscillation frequency increases by 30% at a dose of 0.7 C cm{sup -2}. Features of physics of EBM of an oscillator are outlined considering the contribution of the metal and semiconductor phases of the switching channel. Controlled modification allows EBM forming of switches with preset parameters. Also, it might be used in artificial oscillatory neural networks for pattern recognition based on frequency shift keying. (copyright 2017 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  8. AUC-Maximizing Ensembles through Metalearning.

    Science.gov (United States)

    LeDell, Erin; van der Laan, Mark J; Petersen, Maya

    2016-05-01

    Area Under the ROC Curve (AUC) is often used to measure the performance of an estimator in binary classification problems. An AUC-maximizing classifier can have significant advantages in cases where ranking correctness is valued or if the outcome is rare. In a Super Learner ensemble, maximization of the AUC can be achieved by the use of an AUC-maximining metalearning algorithm. We discuss an implementation of an AUC-maximization technique that is formulated as a nonlinear optimization problem. We also evaluate the effectiveness of a large number of different nonlinear optimization algorithms to maximize the cross-validated AUC of the ensemble fit. The results provide evidence that AUC-maximizing metalearners can, and often do, out-perform non-AUC-maximizing metalearning methods, with respect to ensemble AUC. The results also demonstrate that as the level of imbalance in the training data increases, the Super Learner ensemble outperforms the top base algorithm by a larger degree.

  9. Modification of beta dose evaluation algorithm for better accuracy in personnel monitoring

    International Nuclear Information System (INIS)

    Rakesh, R.B.; Kumar, Munish; Sneha, C.; Ratna, P.; Datta, D.

    2016-01-01

    Dose due to beta radiations is the main contributor to the skin dose. Assessment of individual dose (whole body, skin, extremity) in India is based on CaSO 4 :Dy based Teflon embedded TLD badge used for personnel monitoring. The design of the dosemeter enables identification of radiation type which, in turn, allows use of radiation specific algorithm for dose evaluation. The difference of response of three discs of the TLD badge to beta radiation in beta/beta-gamma fields is due to the presence of different filters corresponding to the three discs. The response of disc under metal filter (D 1 ) to beta being negligible while that of open disc (D 3 ) is the maximum. The ratio of response of open disc to that under Perspex (D 3 /D 2 ) to beta is highly dependent on its energy and angle of incidence. Therefore estimation of dose due to beta is based on response of open disc corrected for the energy of beta using D 3 /D 2

  10. Medical and occupational dose reduction in pediatric barium meal procedures

    Science.gov (United States)

    Filipov, D.; Schelin, H. R.; Denyak, V.; Paschuk, S. A.; Ledesma, J. A.; Legnani, A.; Bunick, A. P.; Sauzen, J.; Yagui, A.; Vosiak, P.

    2017-11-01

    Doses received in pediatric Barium Meal procedure can be rather high. It is possible to reduce dose values following the recommendations of the European Communities (EC) and the International Commission on Radiological Protection (ICRP). In the present work, the modifications of radiographic techniques made in a Brazilian hospital according to the EC and the ICRP recommendations and their influence on medical and occupational exposure are reported. The procedures of 49 patients before and 44 after the optimization were studied and air kerma-area product (PK,A) values and the effective doses were evaluated. The occupational equivalent doses were measured next to the eyes, under the thyroid shield and on each hand of both professionals who remained inside the examination room. The implemented modifications reduced by 70% and 60% the PK,A and the patient effective dose, respectively. The obtained dose values are lower than approximately 75% of the results from similar studies. The occupational annual equivalent doses for all studied organs became lower than the limits set by the ICRP. The equivalent doses in one examination were on average below than 75% of similar studies.

  11. Underling modification in ion beam induced Si wafers

    International Nuclear Information System (INIS)

    Hazra, S.; Chini, T.K.; Sanyal, M.K.; Grenzer, J.; Pietsch, U.

    2005-01-01

    Subsurface (amorphous-crystalline interface) structure of keV ion beam modified Si(001) wafers was studied for the first time using non-destructive technique and compared with that of the top one. Ion-beam modifications of the Si samples were done using state-of-art high-current ion implanter facility at Saha Institute of Nuclear Physics by changing energy, dose and angle of incidence of the Ar + ion beam. To bring out the underlying modification depth-resolved x-ray grazing incidence diffraction has been carried out using synchrotron radiation facility, while the structure of the top surface was studied through atomic force microscopy

  12. Is CP violation maximal

    International Nuclear Information System (INIS)

    Gronau, M.

    1984-01-01

    Two ambiguities are noted in the definition of the concept of maximal CP violation. The phase convention ambiguity is overcome by introducing a CP violating phase in the quark mixing matrix U which is invariant under rephasing transformations. The second ambiguity, related to the parametrization of U, is resolved by finding a single empirically viable definition of maximal CP violation when assuming that U does not single out one generation. Considerable improvement in the calculation of nonleptonic weak amplitudes is required to test the conjecture of maximal CP violation. 21 references

  13. Shareholder, stakeholder-owner or broad stakeholder maximization

    OpenAIRE

    Mygind, Niels

    2004-01-01

    With reference to the discussion about shareholder versus stakeholder maximization it is argued that the normal type of maximization is in fact stakeholder-owner maxi-mization. This means maximization of the sum of the value of the shares and stake-holder benefits belonging to the dominating stakeholder-owner. Maximization of shareholder value is a special case of owner-maximization, and only under quite re-strictive assumptions shareholder maximization is larger or equal to stakeholder-owner...

  14. Etikken bag kunstig selektion og genmodifikation af planter: The Ethics of Artificial Selection and Genetic Modification of Plants

    OpenAIRE

    Armstrong, Freya; Børgesen, Lasse Faber; Gierløff, Anders Pihl; Justesen, Louise; Niemeier, Sebastian; Sandgaard, Monica; Steensgaard, Ida Mathilde

    2013-01-01

    Artificial selection and genetic modification are both methods which are used to maximize crop profit. The recent years’ development in the genetic engineering sector has made it possible to transfer a specific trait from one organism to another. The development has caused a widespread ethical debate on the subject. This study examines two different cases based on genetic modification and artificial selection of plants respectively. The aim of this study is to determine, which ethics particip...

  15. Surface modifications of polypropylene by high energy carbon ions

    International Nuclear Information System (INIS)

    Saha, A.; Chakraborty, V.; Dutta, R.K.; Chintalapudi, S.N.

    2000-01-01

    Polypropylene was irradiated with 12 C ions of 3.6 and 5.4 MeV energies using 3 MV tandem accelerator. The surface modification was investigated by Scanning Electron Microscopy (SEM). Optical changes were monitored by UV-VIS and FTIR spectroscopy. At the lowest ion fluence, only blister formation of various sizes (1-6 μm) was observed. Polymer when irradiated at a fluence of 1x10 14 ions/cm 2 exhibited a network structure. A comparative study on dose dependence of surface and bulk modification has been described. (author)

  16. Task-oriented maximally entangled states

    International Nuclear Information System (INIS)

    Agrawal, Pankaj; Pradhan, B

    2010-01-01

    We introduce the notion of a task-oriented maximally entangled state (TMES). This notion depends on the task for which a quantum state is used as the resource. TMESs are the states that can be used to carry out the task maximally. This concept may be more useful than that of a general maximally entangled state in the case of a multipartite system. We illustrate this idea by giving an operational definition of maximally entangled states on the basis of communication tasks of teleportation and superdense coding. We also give examples and a procedure to obtain such TMESs for n-qubit systems.

  17. SPECIAL CONSIDERATIONS REGARDING WARFARIN DOSE TITRATION IN PATIENTS WITH ATRIAL FIBRILLATION DEPENDING ON CLINICAL FACTORS

    Directory of Open Access Journals (Sweden)

    E. L. Artanova

    2011-01-01

    Full Text Available Aim. To study the relations of clinical characteristics and individual warfarin dose titration in patients with atrial fibrillation. Material and methods. Period of warfarin dose titration was analyzed in 68 patients with atrial fibrillation due to ischemic heart disease. Adjusted warfarin dose in milligram, duration of dose titration in days and maximal international normalized ratio (INR were taken into account. Sex, age, history of myocardial infarction and stroke, concomitant diseases, amiodarone therapy were considered among clinical characteristics. Results. Adjusted warfarin dose was significantly higher in obesity , and it was lower in case of experienced myocardial infarction. The INR highest levels and maximal amplitudes of its fluctuations were observed in patients with thyroid gland nodes and smokers. Period of warfarin dose titration was longer in patients treated with amiodarone. Conclusion. Warfarin dose titration in patients with atrial fibrillation depends on the presence of myocardial infarction, obesity , thyroid nodular changes, smoking and amiodarone treatment.

  18. FLOUTING MAXIMS IN INDONESIA LAWAK KLUB CONVERSATION

    Directory of Open Access Journals (Sweden)

    Rahmawati Sukmaningrum

    2017-04-01

    Full Text Available This study aims to identify the types of maxims flouted in the conversation in famous comedy show, Indonesia Lawak Club. Likewise, it also tries to reveal the speakers‘ intention of flouting the maxim in the conversation during the show. The writers use descriptive qualitative method in conducting this research. The data is taken from the dialogue of Indonesia Lawak club and then analyzed based on Grice‘s cooperative principles. The researchers read the dialogue‘s transcripts, identify the maxims, and interpret the data to find the speakers‘ intention for flouting the maxims in the communication. The results show that there are four types of maxims flouted in the dialogue. Those are maxim of quality (23%, maxim of quantity (11%, maxim of manner (31%, and maxim of relevance (35. Flouting the maxims in the conversations is intended to make the speakers feel uncomfortable with the conversation, show arrogances, show disagreement or agreement, and ridicule other speakers.

  19. Study of dose distribution in high energy photon beam used in radiotherapy

    International Nuclear Information System (INIS)

    Rafaravavy, R.; Raoelina Andriambololona; Bridier, A.

    2007-01-01

    The dose distribution in a medium traversed by a photon beam depends on beam energy, field size and medium nature. Percent depth dose (PDD), Dose Profile (DP) and Opening Collimator Factor (OCF) curves will be established to study this distribution. So, the PDD curves are composed by tree parts: the build-up region, the maximal dose and the quasi-equilibrium region. The maximum dose depth and the dose in depth increase with increasing photon beam energy but the dose surface decreases. The PDD increases with increasing field size.

  20. Modification of species-based differential evolution for multimodal optimization

    Science.gov (United States)

    Idrus, Said Iskandar Al; Syahputra, Hermawan; Firdaus, Muliawan

    2015-12-01

    At this time optimization has an important role in various fields as well as between other operational research, industry, finance and management. Optimization problem is the problem of maximizing or minimizing a function of one variable or many variables, which include unimodal and multimodal functions. Differential Evolution (DE), is a random search technique using vectors as an alternative solution in the search for the optimum. To localize all local maximum and minimum on multimodal function, this function can be divided into several domain of fitness using niching method. Species-based niching method is one of method that build sub-populations or species in the domain functions. This paper describes the modification of species-based previously to reduce the computational complexity and run more efficiently. The results of the test functions show species-based modifications able to locate all the local optima in once run the program.

  1. VIOLATION OF CONVERSATION MAXIM ON TV ADVERTISEMENTS

    Directory of Open Access Journals (Sweden)

    Desak Putu Eka Pratiwi

    2015-07-01

    Full Text Available Maxim is a principle that must be obeyed by all participants textually and interpersonally in order to have a smooth communication process. Conversation maxim is divided into four namely maxim of quality, maxim of quantity, maxim of relevance, and maxim of manner of speaking. Violation of the maxim may occur in a conversation in which the information the speaker has is not delivered well to his speaking partner. Violation of the maxim in a conversation will result in an awkward impression. The example of violation is the given information that is redundant, untrue, irrelevant, or convoluted. Advertisers often deliberately violate the maxim to create unique and controversial advertisements. This study aims to examine the violation of maxims in conversations of TV ads. The source of data in this research is food advertisements aired on TV media. Documentation and observation methods are applied to obtain qualitative data. The theory used in this study is a maxim theory proposed by Grice (1975. The results of the data analysis are presented with informal method. The results of this study show an interesting fact that the violation of maxim in a conversation found in the advertisement exactly makes the advertisements very attractive and have a high value.

  2. Finding Maximal Quasiperiodicities in Strings

    DEFF Research Database (Denmark)

    Brodal, Gerth Stølting; Pedersen, Christian N. S.

    2000-01-01

    of length n in time O(n log n) and space O(n). Our algorithm uses the suffix tree as the fundamental data structure combined with efficient methods for merging and performing multiple searches in search trees. Besides finding all maximal quasiperiodic substrings, our algorithm also marks the nodes......Apostolico and Ehrenfeucht defined the notion of a maximal quasiperiodic substring and gave an algorithm that finds all maximal quasiperiodic substrings in a string of length n in time O(n log2 n). In this paper we give an algorithm that finds all maximal quasiperiodic substrings in a string...... in the suffix tree that have a superprimitive path-label....

  3. Improvement of plant parameters of the ROBO gamma irradiation facility due to design modification

    International Nuclear Information System (INIS)

    Moussa, A.; Othman, I.; Chu, R.

    1999-01-01

    Two industrial scale, ROBO type Co 60 gamma irradiation facilities have recently been put into operation in Syria and Peru, and the dosimetry commissioning of both plants have been carried out to determine dose distribution with products and to calculate plant parameters such as efficiency, dose uniformity ratio and throughput. There are some design modifications between the two plants in connection with the location of the carriers with respect to the source plaque and also to each other. The effect of these construction modifications on the plant parameters is discussed in the analysis of the dose distribution data measured in the carriers with depth and height among the four irradiation rows on both sides of the source plaque. The plant parameters were also calculated and measured results were compared to each other. (author)

  4. Improved NGL recovery designs maximize operating flexibility and product recoveries

    International Nuclear Information System (INIS)

    Wilkinson, J.D.; Hudson, H.M.

    1992-01-01

    This paper reports that the historically cyclical nature in the market for ethane and propane has demonstrated the need for flexible natural gas liquids (NGL) recovery plants. NEwly developed and patented processes are now available which can provide ultra-high recovery of ethane (95%+) when demand for ethane is high and provide essentially complete ethane rejection without the normally concomitant reduction in propane recovery. This provides plant operators the flexibility to respond more readily to NGL market conditions, thus maximizing plant operating profits. The new process designs provide this flexibility without increasing utility requirements. In fact, utility consumption is often lower when compared to conventional designs. This same process technology can also be easily retrofit into existing plants with relatively quick payout of the modifications from both recovery and efficiency improvements

  5. Lifestyle and metabolic approaches to maximizing erectile and vascular health.

    Science.gov (United States)

    Meldrum, D R; Gambone, J C; Morris, M A; Esposito, K; Giugliano, D; Ignarro, L J

    2012-01-01

    Oxidative stress and inflammation, which disrupt nitric oxide (NO) production directly or by causing resistance to insulin, are central determinants of vascular diseases including ED. Decreased vascular NO has been linked to abdominal obesity, smoking and high intakes of fat and sugar, which all cause oxidative stress. Men with ED have decreased vascular NO and circulating and cellular antioxidants. Oxidative stress and inflammatory markers are increased in men with ED, and all increase with age. Exercise increases vascular NO, and more frequent erections are correlated with decreased ED, both in part due to stimulation of endothelial NO production by shear stress. Exercise and weight loss increase insulin sensitivity and endothelial NO production. Potent antioxidants or high doses of weaker antioxidants increase vascular NO and improve vascular and erectile function. Antioxidants may be particularly important in men with ED who smoke, are obese or have diabetes. Omega-3 fatty acids reduce inflammatory markers, decrease cardiac death and increase endothelial NO production, and are therefore critical for men with ED who are under age 60 years, and/or have diabetes, hypertension or coronary artery disease, who are at increased risk of serious or even fatal cardiac events. Phosphodiesterase inhibitors have recently been shown to improve antioxidant status and NO production and allow more frequent and sustained penile exercise. Some angiotensin II receptor blockers decrease oxidative stress and improve vascular and erectile function and are therefore preferred choices for lowering blood pressure in men with ED. Lifestyle modifications, including physical and penile-specific exercise, weight loss, omega-3 and folic acid supplements, reduced intakes of fat and sugar, and improved antioxidant status through diet and/or supplements should be integrated into any comprehensive approach to maximizing erectile function, resulting in greater overall success and patient

  6. Brachytherapy radiation doses to the neurovascular bundles

    International Nuclear Information System (INIS)

    Di Biase, Steven J.; Wallner, Kent; Tralins, Kevin; Sutlief, Steven

    2000-01-01

    Purpose: To investigate the role of radiation dose to the neurovascular bundles (NVB) in brachytherapy-related impotence. Methods and Materials: Fourteen Pd-103 or I-125 implant patients were studied. For patients treated with implant alone, the prostate and margin (clinical target volume [CTV]) received a prescription dose of 144 Gy for I-125 or 115 Gy for Pd-103. Two patients received Pd-103 (90 Gy) with 46 Gy supplemental external beam radiation (EBRT). Axial CT images were acquired 2 to 4 hours postoperatively for postimplant dosimetry. Because the NVBs cannot be visualized on CT, NVB calculation points were determined according to previously published anatomic descriptions. Bilateral NVB points were considered to lie posterior-laterally, approximately 2 mm from the prostatic capsule. NVB doses were recorded bilaterally, at 0.5-cm intervals from the prostatic base. Results: For Pd-103, the average NVB doses ranged from 150 Gy to 260 Gy, or 130% to 226% of the prescription dose. For I-125, the average NVB dose ranged from 200 Gy to 325 Gy, or 140% to 225% of the prescription dose. These was no consistent relationship between the NVB dose and the distance from the prostatic base. To examine the possible effect of minor deviations of our calculation points from the true NVB location, we performed NVB calculations at points 2 mm medial or lateral from the NVB calculation point in 8 patients. Doses at these alternate calculation points were comparable, although there was greater variability with small changes in the calculation point if sources were located outside the capsule, near the NVB calculation point. Three patients who developed early postimplant impotence had maximal NVB doses that far exceeded the average values. Conclusions: In the next few years, we hope to clarify the role of high NVB radiation doses on potency, by correlating NVB dose calculations with a large number of patients enrolled in an ongoing I-125 versus Pd-103 trial for early-stage patients

  7. Modification of a cyclo-olefin surface by radio-sterilization: is there any effect on the interaction with drug solutions?

    Science.gov (United States)

    Barakat, Hala; Saunier, Johanna; Aymes Chodur, Caroline; Aubert, Pascal; Vigneron, Jackie; Etcheberry, Arnaud; Yagoubi, Najet

    2013-11-01

    A cyclo-olefin copolymer was subjected to an e-beam ionizing treatment. Two doses were studied: one corresponding to the recommended dose for the sterilization of pharmaceutical packaging (25 kGy), and a greater one to enhance the modifications caused by the treatment (150 kGy). The surface modifications were studied by X-ray photoelectron spectroscopy (XPS), contact angle measurements and atomic force microscopy (AFM). The roughness and the wettability of the surface were enhanced by the treatment. The consequences of the surface modifications on the drug interaction with the polymer were studied. Copyright © 2013 Elsevier B.V. All rights reserved.

  8. A cyclotron isotope production facility designed to maximize production and minimize radiation dose

    International Nuclear Information System (INIS)

    Dickie, W.J.; Stevenson, N.R.; Szlavik, F.F.

    1993-01-01

    Continuing increases in requirements from the nuclear medicine industry for cyclotron isotopes is increasing the demands being put on an aging stock of machines. In addition, with the 1990 recommendations of the ICRP publication in place, strict dose limits will be required and this will have an effect on the way these machines are being operated. Recent advances in cyclotron design combined with lessons learned from two decades of commercial production mean that new facilities can result in a substantial charge on target, low personnel dose, and minimal residual activation. An optimal facility would utilize a well engineered variable energy/high current H - cyclotron design, multiple beam extraction, and individual target caves. Materials would be selected to minimize activation and absorb neutrons. Equipment would be designed to minimize maintenance activities performed in high radiation fields. (orig.)

  9. Radiation dose assessment in nuclear medicine

    International Nuclear Information System (INIS)

    Stabin, M.G.

    2002-01-01

    In any application involving the use of ionizing radiation in humans, risks and benefits must be properly evaluated and balanced. Radionuclides are used in nuclear medicine in a variety of diagnostic and therapeutic procedures. Recently, interest has grown in therapeutic agents for a number of applications in nuclear medicine, particularly in the treatment of hematologic and non-hematologic malignancies. This has heightened interest in the need for radiation dose calculations and challenged the scientific community to develop more patient-specific and relevant dose models. Consideration of radiation dose in such studies is central to efforts to maximize dose to tumor while sparing normal tissues. In many applications, a significant absorbed dose may be received by some radiosensitive organs, particularly the active marrow. This talk will review the methods and models used in internal dosimetry in nuclear medicine, and discuss some current trends and challenges in this field

  10. Boron neutron capture therapy using mixed epithermal and thermal neutron beams in patients with malignant glioma-correlation between radiation dose and radiation injury and clinical outcome

    International Nuclear Information System (INIS)

    Kageji, Teruyoshi; Nagahiro, Shinji; Matsuzaki, Kazuhito; Mizobuchi, Yoshifumi; Toi, Hiroyuki; Nakagawa, Yoshinobu; Kumada, Hiroaki

    2006-01-01

    Purpose: To clarify the correlation between the radiation dose and clinical outcome of sodium borocaptate-based intraoperative boron neutron capture therapy in patients with malignant glioma. Methods and Materials: The first protocol (P1998, n = 8) prescribed a maximal gross tumor volume (GTV) dose of 15 Gy. In 2001, a dose-escalated protocol was introduced (P2001, n 11), which prescribed a maximal vascular volume dose of 15 Gy or, alternatively, a clinical target volume (CTV) dose of 18 Gy. Results: The GTV and CTV doses in P2001 were 1.1-1.3 times greater than those in P1998. The maximal vascular volume dose of those with acute radiation injury was 15.8 Gy. The mean GTV and CTV dose in long-term survivors with glioblastoma was 26.4 and 16.5 Gy, respectively. A statistically significant correlation between the GTV dose and median survival time was found. In the 11 glioblastoma patients in P2001, the median survival time was 19.5 months and 1- and 2-year survival rate was 60.6% and 37.9%, respectively. Conclusion: Dose escalation contributed to the improvement in clinical outcome. To avoid radiation injury, the maximal vascular volume dose should be <12 Gy. For long-term survival in patients with glioblastoma after boron neutron capture therapy, the optimal mean dose of the GTV and CTV was 26 and 16 Gy, respectively

  11. Shareholder, stakeholder-owner or broad stakeholder maximization

    DEFF Research Database (Denmark)

    Mygind, Niels

    2004-01-01

    With reference to the discussion about shareholder versus stakeholder maximization it is argued that the normal type of maximization is in fact stakeholder-owner maxi-mization. This means maximization of the sum of the value of the shares and stake-holder benefits belonging to the dominating...... including the shareholders of a company. Although it may be the ultimate goal for Corporate Social Responsibility to achieve this kind of maximization, broad stakeholder maximization is quite difficult to give a precise definition. There is no one-dimensional measure to add different stakeholder benefits...... not traded on the mar-ket, and therefore there is no possibility for practical application. Broad stakeholder maximization instead in practical applications becomes satisfying certain stakeholder demands, so that the practical application will be stakeholder-owner maximization un-der constraints defined...

  12. On the maximal superalgebras of supersymmetric backgrounds

    International Nuclear Information System (INIS)

    Figueroa-O'Farrill, Jose; Hackett-Jones, Emily; Moutsopoulos, George; Simon, Joan

    2009-01-01

    In this paper we give a precise definition of the notion of a maximal superalgebra of certain types of supersymmetric supergravity backgrounds, including the Freund-Rubin backgrounds, and propose a geometric construction extending the well-known construction of its Killing superalgebra. We determine the structure of maximal Lie superalgebras and show that there is a finite number of isomorphism classes, all related via contractions from an orthosymplectic Lie superalgebra. We use the structure theory to show that maximally supersymmetric waves do not possess such a maximal superalgebra, but that the maximally supersymmetric Freund-Rubin backgrounds do. We perform the explicit geometric construction of the maximal superalgebra of AdS 4 X S 7 and find that it is isomorphic to osp(1|32). We propose an algebraic construction of the maximal superalgebra of any background asymptotic to AdS 4 X S 7 and we test this proposal by computing the maximal superalgebra of the M2-brane in its two maximally supersymmetric limits, finding agreement.

  13. SU-F-J-86: Method to Include Tissue Dose Response Effect in Deformable Image Registration

    Energy Technology Data Exchange (ETDEWEB)

    Zhu, J; Liang, J; Chen, S; Qin, A; Yan, D [Beaumont Health Systeml, Royal Oak, MI (United States)

    2016-06-15

    Purpose: Organ changes shape and size during radiation treatment due to both mechanical stress and radiation dose response. However, the dose response induced deformation has not been considered in conventional deformable image registration (DIR). A novel DIR approach is proposed to include both tissue elasticity and radiation dose induced organ deformation. Methods: Assuming that organ sub-volume shrinkage was proportional to the radiation dose induced cell killing/absorption, the dose induced organ volume change was simulated applying virtual temperature on each sub-volume. Hence, both stress and heterogeneity temperature induced organ deformation. Thermal stress finite element method with organ surface boundary condition was used to solve deformation. Initial boundary correspondence on organ surface was created from conventional DIR. Boundary condition was updated by an iterative optimization scheme to minimize elastic deformation energy. The registration was validated on a numerical phantom. Treatment dose was constructed applying both the conventional DIR and the proposed method using daily CBCT image obtained from HN treatment. Results: Phantom study showed 2.7% maximal discrepancy with respect to the actual displacement. Compared with conventional DIR, subvolume displacement difference in a right parotid had the mean±SD (Min, Max) to be 1.1±0.9(−0.4∼4.8), −0.1±0.9(−2.9∼2.4) and −0.1±0.9(−3.4∼1.9)mm in RL/PA/SI directions respectively. Mean parotid dose and V30 constructed including the dose response induced shrinkage were 6.3% and 12.0% higher than those from the conventional DIR. Conclusion: Heterogeneous dose distribution in normal organ causes non-uniform sub-volume shrinkage. Sub-volume in high dose region has a larger shrinkage than the one in low dose region, therefore causing more sub-volumes to move into the high dose area during the treatment course. This leads to an unfavorable dose-volume relationship for the normal organ

  14. Dose reduction and optimization studies (ALARA) at nuclear power facilities

    International Nuclear Information System (INIS)

    Baum, J.W.; Meinhold, C.B.

    1983-01-01

    Brookhaven National Laboratory (BNL) has been commissioned by the Nuclear Regulatory Commission (NRC) to study dose-reduction techniques and effectiveness of as low as reasonably achievable (ALARA) planning at LWR plants. These studies have the following objectives: identify high-dose maintenance tasks; identify dose-reduction techniques; examine incentives for dose reduction; evaluate cost-effectiveness and optimization of dose-reduction techniques; and compile an ALARA handbook on data, engineering modifications, cost-effectiveness calculations, and other information of interest to ALARA practioners

  15. Maximally multipartite entangled states

    Science.gov (United States)

    Facchi, Paolo; Florio, Giuseppe; Parisi, Giorgio; Pascazio, Saverio

    2008-06-01

    We introduce the notion of maximally multipartite entangled states of n qubits as a generalization of the bipartite case. These pure states have a bipartite entanglement that does not depend on the bipartition and is maximal for all possible bipartitions. They are solutions of a minimization problem. Examples for small n are investigated, both analytically and numerically.

  16. Maximally Symmetric Composite Higgs Models.

    Science.gov (United States)

    Csáki, Csaba; Ma, Teng; Shu, Jing

    2017-09-29

    Maximal symmetry is a novel tool for composite pseudo Goldstone boson Higgs models: it is a remnant of an enhanced global symmetry of the composite fermion sector involving a twisting with the Higgs field. Maximal symmetry has far-reaching consequences: it ensures that the Higgs potential is finite and fully calculable, and also minimizes the tuning. We present a detailed analysis of the maximally symmetric SO(5)/SO(4) model and comment on its observational consequences.

  17. Thermoluminescent dosimetry and assessment of personal dose

    International Nuclear Information System (INIS)

    Boas, J.F.; Martin, L.J.; Young, J.G.

    1982-01-01

    Thermoluminescence is discussed in terms of the energy band structure of a crystalline solid and the trapping of charge carriers by point defects. Some general properties of thermoluminescent materials used for dosimetry are outlined, with thermoluminescence of CaSO 4 :Dy being described in detail. The energy response function and the modification of the energy response of a dosimeter by shielding are discussed. The final section covers the connection between exposure, as recorded by a TLD badge, and the absorbed dose to various organs from gamma radiation in a uranium mine; the conversion from absorbed dose to dose equivalent; and uncertainties in assessment of dose equivalent

  18. On enzyme kinetic parameters modification of gamma irradiation

    International Nuclear Information System (INIS)

    Ferdes, O.S.; Ferdes, M.; Turcu, G.R.

    1993-01-01

    To elucidate the molecular mechanisms of gamma-ray action on biomolecules there were investigated the modifications in activity and other kinetic parameters for some enzymes irradiated in pure dry state at relative high doses. There were considered bacterial and fungal α-amylases, glucoamylase and Mucor sp. protease irradiated by a 60 Co gamma-ray source in the dose range 1.0-30.0 kGy, at different dose-rates between 0.5-2.0 kGy/h, at room temperature. Considering the enzyme inactivation in this dose range, the dose-effect relationships have an expected form and depend on the irradiation conditions but not significantly on the dose rate. The catalytic properties of enzymes were modified by irradiation. By usual methods it is evidenced a direct correlation between the enzymatic activities, Michaelis-Menten constant, K m , reaction velocities, v, and the irradiation dose. These experimental findings can support a self-consistent theoretical approach on biophysical radiation action on biological active molecules like enzymes. At the same time, some enzyme behaviour to irradiation could be considered like a good biological indicator of radiation response. (Author) 4 Figs., 19 Refs

  19. Maximal quantum Fisher information matrix

    International Nuclear Information System (INIS)

    Chen, Yu; Yuan, Haidong

    2017-01-01

    We study the existence of the maximal quantum Fisher information matrix in the multi-parameter quantum estimation, which bounds the ultimate precision limit. We show that when the maximal quantum Fisher information matrix exists, it can be directly obtained from the underlying dynamics. Examples are then provided to demonstrate the usefulness of the maximal quantum Fisher information matrix by deriving various trade-off relations in multi-parameter quantum estimation and obtaining the bounds for the scalings of the precision limit. (paper)

  20. Correlation of patient maximum skin doses in cardiac procedures with various dose indicators

    International Nuclear Information System (INIS)

    Domienik, J.; Papierz, S.; Jankowski, J.; Peruga, J.Z.; Werduch, A.; Religa, W.

    2008-01-01

    In most countries of European Union, legislation requires the determination of the total skin dose received by patients during interventional procedures in order to prevent deterministic damages. Various dose indicators like dose-area product (DAP), cumulative dose (CD) and entrance dose at the patient plane (EFD) are used for patient dosimetry purposes in clinical practice. This study aimed at relating those dose indicators with doses ascribed to the most irradiated areas of the patient skin usually expressed in terms of local maximal skin dose (MSD). The study was performed in two different facilities for two most common cardiac procedures coronary angiography (CA) and percutaneous coronary interventions (PCI). For CA procedures, the registered values of fluoroscopy time, total DAP and MSD were in the range (0.7-27.3) min, (16-317) Gy cm 2 and (43-1507) mGy, respectively, and for interventions, accordingly (2.1-43.6) min, (17-425) Gy cm 2 , (71-1555) mGy. Moreover, for CA procedures, CD and EFD were in the ranges (295-4689) mGy and (121-1768) mGy and for PCI (267-6524) mGy and (68-2279) mGy, respectively. No general and satisfactory correlation was found for safe estimation of MSD. However, results show that the best dose indicator which might serve for rough, preliminary estimation is DAP value. In the study, the appropriate trigger levels were proposed for both facilities. (authors)

  1. Understanding Violations of Gricean Maxims in Preschoolers and Adults

    Directory of Open Access Journals (Sweden)

    Mako eOkanda

    2015-07-01

    Full Text Available This study used a revised Conversational Violations Test to examine Gricean maxim violations in 4- to 6-year-old Japanese children and adults. Participants’ understanding of the following maxims was assessed: be informative (first maxim of quantity, avoid redundancy (second maxim of quantity, be truthful (maxim of quality, be relevant (maxim of relation, avoid ambiguity (second maxim of manner, and be polite (maxim of politeness. Sensitivity to violations of Gricean maxims increased with age: 4-year-olds’ understanding of maxims was near chance, 5-year-olds understood some maxims (first maxim of quantity and maxims of quality, relation, and manner, and 6-year-olds and adults understood all maxims. Preschoolers acquired the maxim of relation first and had the greatest difficulty understanding the second maxim of quantity. Children and adults differed in their comprehension of the maxim of politeness. The development of the pragmatic understanding of Gricean maxims and implications for the construction of developmental tasks from early childhood to adulthood are discussed.

  2. Mid-ventilation position planning: Optimal model for dose distribution in lung tumour

    International Nuclear Information System (INIS)

    Benchalal, M.; Leseur, J.; Chajon, E.; Cazoulat, G.; Haigron, P.; Simon, A.; Bellec, J.; Lena, H.; Crevoisier, R. de

    2012-01-01

    Purpose. - The dose distribution for lung tumour is estimated using a 3D-CT scan, and since a person breathes while the images are captured, the dose distribution doesn't reflect the reality. A 4D-CT scan integrates the motion of the tumour during breathing and, therefore, provides us with important information regarding tumour's motion in all directions, the motion volume (ITV) and the time-weighted average position (MVP). Patient and methods. - Based on these two concepts, we have estimated, for a lung carcinoma case a 3D dose distribution from a 3D-CT scan, and a 4D dose distribution from a 4-D CT scan. To this, we have applied a non-rigid registration to estimate the cumulative dose. Results. - Our study shows that the 4D dose estimation of the GTV is almost the same when made using MVP and ITV concepts, but sparring of the healthy lung is better done using the MPV model (MVP), as compared to the ITV model. This improvement of the therapeutic index allows, from a projection on the theoretical maximal dose to PTV (strictly restricted to doses for the lungs and the spinal cord), for an increase of about 11% on the total dose (maximal dose of 86 Gy for the ITV and 96 Gy for the MVP). Conclusion. - Further studies with more patients are needed to confirm our data. (authors)

  3. Maximizing therapeutic gain with gemcitabine and fractionated radiation

    International Nuclear Information System (INIS)

    Mason, Kathy A.; Milas, Luka; Hunter, Nancy R.; Elshaikh, Mohamed; Buchmiller, Lara; Kishi, Kazushi; Hittelman, K. Walter; Ang, K. Kian

    1999-01-01

    Purpose/Objective: The nucleoside analogue gemcitabine inhibits cellular repair and repopulation, induces apoptosis, causes tumor growth delay, and enhances radiation-induced growth delay. After single doses of drug and radiation, maximum enhancement of tumor response was obtained when gemcitabine preceded radiation by at least 24 h. Conversely, the cellular radioresponse of the normal gastrointestinal epithelium was slightly protected when gemcitabine and radiation were separated by 24 h. This differential response created a time frame within which therapeutic gain could be maximized. In our present investigation, we sought to define the most therapeutically beneficial scheme of gemcitabine administration when combined with fractionated radiotherapy. Methods and Materials: C3Hf/Kam mice were given identical drug and radiation schedules of administration, and both normal tissue (jejunal mucosa) and tumor (Sa-NH) responses were measured. Irradiation was given once per day for 5 days in normal tissue and tumor growth delay studies and twice per day for the tumor cure endpoint. A total dose of 25 mg/kg gemcitabine was given i.p. in 1 of 3 schedules: a single dose of 25 mg/kg 24 h before the start of fractionated irradiation, 12.5 mg/kg 24 h before the first and third radiation doses, or 24 h before each of 5 radiation doses. Groups of mice bearing 7- or 8-mm diameter tumors were treated with gemcitabine alone or in combination with fractionated irradiation under ambient or hypoxic conditions. The survival response of the jejunal mucosa was quantified by the microcolony assay and histologically by quantifying apoptosis, mitosis, S-phase fraction, and crypt cellularity. Results: For tumor growth delay, dose-modifying factors (DMFs) were similar (1.34-1.46) for all 3 schedules of drug administration. In contrast, the response of the jejunum was strongly dependent on the schedule of gemcitabine administration. A single dose of gemcitabine before the start of fractionated

  4. Modifications of poly (vinilydene fluoride) under electronic excitations produced by charged particles (heavy ions and electrons)

    International Nuclear Information System (INIS)

    Fina, A.

    1990-04-01

    Some of the physico-chemical properties of organic solids like conductivity or permeation can be improved by irradiation. The aim of this work is to characterize modifications induced in poly (vinylidene fluoride) films (PVDF) by charged particles (ions and electrons), with electronic stopping power, for doses ranging from zero to twenty G-Grays. Influence of dose, density of electronic excitations, and flux (in particles per square centimeter), and the nature of defects induced by the beam, were studied with two methods: X-ray Photoelectron Spectroscopy (or XPS) for surface analysis, and electron Spin Resonance (or ESR) to probe the bulk of the film. Three ranges of doses are revealed in view of experimental results. At lower doses, PVDF undergoes deshydrofluorination induced by desorption; it is a low modifications regime. For intermediate range doses, conjugated carbon backbones of polyene compounds are produced. At higher doses, intermolecular interactions between the resulting fragments give a crosslinked network. For the upper limit of doses used, bond breaking results in a non reversible degradation of PVDF. In this last situation, direct atomic displacement of target atoms, is not negligible [fr

  5. Software enhancements and modifications to Program FDTD executable on the Cray X-MP computer

    Energy Technology Data Exchange (ETDEWEB)

    Stringer, J.C.

    1987-09-04

    This report summarizes enhancements and modifications to PROGRAM FDTD executable on the Cray X-MP computer system. Specifically, the tasks defined and performed under this effort are revision of the material encoding/decoding scheme to allow material type specification on an individual cell basis; modification of the I/O buffering scheme to maximize the use of available central memory and minimize the number of physical I/O accesses; user interface enhancements. Provide enhanced input/output features for greater flexibility; increased modularity. Divide the code into additional modules for ease of maintenance and future enhancements; and assist in the conversion and testing of FDTD to Floating Point Systems scientific computers and associated peripheral devices.

  6. Intensity-Modulated Radiotherapy for Locally Advanced Non-Small-Cell Lung Cancer: A Dose-Escalation Planning Study

    International Nuclear Information System (INIS)

    Lievens, Yolande; Nulens, An; Gaber, Mousa Amr; Defraene, Gilles; De Wever, Walter; Stroobants, Sigrid; Van den Heuvel, Frank

    2011-01-01

    Purpose: To evaluate the potential for dose escalation with intensity-modulated radiotherapy (IMRT) in positron emission tomography-based radiotherapy planning for locally advanced non-small-cell lung cancer (LA-NSCLC). Methods and Materials: For 35 LA-NSCLC patients, three-dimensional conformal radiotherapy and IMRT plans were made to a prescription dose (PD) of 66 Gy in 2-Gy fractions. Dose escalation was performed toward the maximal PD using secondary endpoint constraints for the lung, spinal cord, and heart, with de-escalation according to defined esophageal tolerance. Dose calculation was performed using the Eclipse pencil beam algorithm, and all plans were recalculated using a collapsed cone algorithm. The normal tissue complication probabilities were calculated for the lung (Grade 2 pneumonitis) and esophagus (acute toxicity, grade 2 or greater, and late toxicity). Results: IMRT resulted in statistically significant decreases in the mean lung (p <.0001) and maximal spinal cord (p = .002 and 0005) doses, allowing an average increase in the PD of 8.6-14.2 Gy (p ≤.0001). This advantage was lost after de-escalation within the defined esophageal dose limits. The lung normal tissue complication probabilities were significantly lower for IMRT (p <.0001), even after dose escalation. For esophageal toxicity, IMRT significantly decreased the acute NTCP values at the low dose levels (p = .0009 and p <.0001). After maximal dose escalation, late esophageal tolerance became critical (p <.0001), especially when using IMRT, owing to the parallel increases in the esophageal dose and PD. Conclusion: In LA-NSCLC, IMRT offers the potential to significantly escalate the PD, dependent on the lung and spinal cord tolerance. However, parallel increases in the esophageal dose abolished the advantage, even when using collapsed cone algorithms. This is important to consider in the context of concomitant chemoradiotherapy schedules using IMRT.

  7. Improvement of Off-site Dose Assessment Code for Operating Nuclear Power Plant

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Juyub; Kim, Juyoul; Shin, Kwangyoung [FNC Technology Co. Ltd., Yongin (Korea, Republic of); You, Songjae; Moon, Jongyi [Korea Institute of Nuclear Safety, Daejeon (Korea, Republic of)

    2014-05-15

    XOQDOQ code which calculates atmospheric Dispersion factor was included into INDAC also. A research on the improvement of off-site dose assessment system for an operating nuclear power plant was performed by KINS in 2011. As a result, following improvements were derived: - Separation of dose assessment for new and existing facilities - Update of food ingestion data - Consideration of multi-unit operation and so on In order to reflect the results, INDAC is under modification. INDAC is an integrated dose assessment code for an operating nuclear power plant and consists of three main modules: XOQDOQ, GASDOS and LIQDOS. The modules are under modification in order to improve the accuracy of assessment and usability. Assessment points for multi-unit release can be calculated through the improved code and the method on dose assessment for multi-unit release has been modified, so that the dose assessment result of multi-unit site becomes more realistic by relieving excessive conservatism. Finally, as the accuracy of calculation modules has been improved, the reliability of dose assessment result has been strengthened.

  8. Improvement of plant parameters of the robo gamma irradiation facility due to design modification

    International Nuclear Information System (INIS)

    Kovacs, A.; Moussa, A.; Othman, I.; Del Valle Odar, C.; Seminario, A.; Linares, M.; Huamanlazo, P.; Aymar, J.; Chu, R.

    1998-01-01

    Two industrial scale, 'ROBO' type 60 Co gamma irradiation facilities have recently been put into operation in Syria and Peru, and the dosimetry commissioning of both plants have been carried out to determine dose distribution within products and to calculate plant parameters such as efficiency, dose uniformity ratio and throughput. There are some design modifications between the two plants in connection with the location of the carriers with respect to the source plaque and also to each other. The effect of these construction modifications on the plant parameters is discussed in the analysis of the dose distribution data measured in the carriers with depth and height among the four irradiation rows on both sides of the source plaque. The plant parameters were also calculated for different product densities using the technical data of the facilities, and the calculated and measured results were compared to each other

  9. Modification of the Charlesby law. Pt. 2. Macroscopic sensitivity

    International Nuclear Information System (INIS)

    Schiltz, A.; Weil, A.; Paniez, P.

    1984-01-01

    In part II, results are presented showing that for doses below macroscopic sensitivity, Qsub(sm), degradation due to fluence of the particles seems to be non-uniform over the entire area. In the light of this, a modification of the Charlesby's law is proposed providing a solution to the problems considered in part I [fr

  10. On maximal massive 3D supergravity

    OpenAIRE

    Bergshoeff , Eric A; Hohm , Olaf; Rosseel , Jan; Townsend , Paul K

    2010-01-01

    ABSTRACT We construct, at the linearized level, the three-dimensional (3D) N = 4 supersymmetric " general massive supergravity " and the maximally supersymmetric N = 8 " new massive supergravity ". We also construct the maximally supersymmetric linearized N = 7 topologically massive supergravity, although we expect N = 6 to be maximal at the non-linear level. (Bergshoeff, Eric A) (Hohm, Olaf) (Rosseel, Jan) P.K.Townsend@da...

  11. Modification of polyethersulfone films by grafting hydrophilic monomers with 60Co γ-rays

    International Nuclear Information System (INIS)

    Hou Zhengchi; Deng Bo; Li Jing

    2006-01-01

    Polyethersulfone (PES), with its high strength, high temperature resistance, corrosion- resistance, oxidation resistance and applicability under wide pH range, is used extensively as ultrafiltration and nanofiltration membrane. However, PES membranes foul easily in such an application because of hydrophobic nature of PES raw materials. Improving the hydrophilicity of PES by grafting hydrophilic monomers onto it is of potential to solve the problem. At present, common approaches to improve hydrophilicity of PES membranes are UV grafting modification, plasma modification, and chemical modification, whereas grafting and modifying PES films by 60 Co γ-rays has rarely been reported. Studies have been carried out in our laboratory to graft hydrophilic monomers onto PES membranes directly or PES powders via simultaneous radiation grafting with the rays. Acrylic acid, methyl acrylic acid or acrylamide was used to study effects of the monomer concentration, irradiation dose and dose rate, solvent, inhibitor and pH of the grafting solution on the degree of grafting. The results showed that hydrophilicity of all the PES membranes could be improved, with the extent of improvement being dependent on the grafting conditions. (authors)

  12. Inclusive fitness maximization: An axiomatic approach.

    Science.gov (United States)

    Okasha, Samir; Weymark, John A; Bossert, Walter

    2014-06-07

    Kin selection theorists argue that evolution in social contexts will lead organisms to behave as if maximizing their inclusive, as opposed to personal, fitness. The inclusive fitness concept allows biologists to treat organisms as akin to rational agents seeking to maximize a utility function. Here we develop this idea and place it on a firm footing by employing a standard decision-theoretic methodology. We show how the principle of inclusive fitness maximization and a related principle of quasi-inclusive fitness maximization can be derived from axioms on an individual׳s 'as if preferences' (binary choices) for the case in which phenotypic effects are additive. Our results help integrate evolutionary theory and rational choice theory, help draw out the behavioural implications of inclusive fitness maximization, and point to a possible way in which evolution could lead organisms to implement it. Copyright © 2014 Elsevier Ltd. All rights reserved.

  13. Internal dose assessment in radiation accidents

    International Nuclear Information System (INIS)

    Toohey, R.E.

    2003-01-01

    Although numerous models have been developed for occupational and medical internal dosimetry, they may not be applicable to an accident situation. Published dose coefficients relate effective dose to intake, but if acute deterministic effects are possible, effective dose is not a useful parameter. Consequently, dose rates to the organs of interest need to be computed from first principles. Standard bioassay methods may be used to assess body contents, but, again, the standard models for bioassay interpretation may not be applicable because of the circumstances of the accident and the prompt initiation of decorporation therapy. Examples of modifications to the standard methodologies include adjustment of biological half-times under therapy, such as in the Goiania accident, and the same effect, complicated by continued input from contaminated wounds, in the Hanford 241 Am accident. (author)

  14. Ultralow energy ion beam surface modification of low density polyethylene.

    Science.gov (United States)

    Shenton, Martyn J; Bradley, James W; van den Berg, Jaap A; Armour, David G; Stevens, Gary C

    2005-12-01

    Ultralow energy Ar+ and O+ ion beam irradiation of low density polyethylene has been carried out under controlled dose and monoenergetic conditions. XPS of Ar+-treated surfaces exposed to ambient atmosphere show that the bombardment of 50 eV Ar+ ions at a total dose of 10(16) cm(-2) gives rise to very reactive surfaces with oxygen incorporation at about 50% of the species present in the upper surface layer. Using pure O+ beam irradiation, comparatively low O incorporation is achieved without exposure to atmosphere (approximately 13% O in the upper surface). However, if the surface is activated by Ar+ pretreatment, then large oxygen contents can be achieved under subsequent O+ irradiation (up to 48% O). The results show that for very low energy (20 eV) oxygen ions there is a dose threshold of about 5 x 10(15) cm(-2) before surface oxygen incorporation is observed. It appears that, for both Ar+ and O+ ions in this regime, the degree of surface modification is only very weakly dependent on the ion energy. The results suggest that in the nonequilibrium plasma treatment of polymers, where the ion flux is typically 10(18) m(-2) s(-1), low energy ions (<50 eV) may be responsible for surface chemical modification.

  15. Analysis of Dose Response for Circulatory Disease After Radiotherapy for Benign Disease

    Energy Technology Data Exchange (ETDEWEB)

    Little, Mark P., E-mail: mark.little@nih.gov [Radiation Epidemiology Branch, National Cancer Institute, Executive Plaza South, Rockville, Maryland (United States); Kleinerman, Ruth A. [Radiation Epidemiology Branch, National Cancer Institute, Executive Plaza South, Rockville, Maryland (United States); Stovall, Marilyn; Smith, Susan A. [Department of Radiation Physics, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Mabuchi, Kiyohiko [Radiation Epidemiology Branch, National Cancer Institute, Executive Plaza South, Rockville, Maryland (United States)

    2012-12-01

    Purpose: To assess the shape of the dose-response for various circulatory disease endpoints, and modifiers by age and time since exposure. Methods and Materials: This was an analysis of the US peptic ulcer data testing for heterogeneity of radiogenic risk by circulatory disease endpoint (ischemic heart, cerebrovascular, other circulatory disease). Results: There were significant excess risks for all circulatory disease, with an excess relative risk Gy{sup -1} of 0.082 (95% CI 0.031-0.140), and ischemic heart disease, with an excess relative risk Gy{sup -1} of 0.102 (95% CI 0.039-0.174) (both p = 0.01), and indications of excess risk for stroke. There were no statistically significant (p > 0.2) differences between risks by endpoint, and few indications of curvature in the dose-response. There were significant (p < 0.001) modifications of relative risk by time since exposure, the magnitude of which did not vary between endpoints (p > 0.2). Risk modifications were similar if analysis was restricted to patients receiving radiation, although the relative risks were slightly larger and the risk of stroke failed to be significant. The slopes of the dose-response were generally consistent with those observed in the Japanese atomic bomb survivors and in occupationally and medically exposed groups. Conclusions: There were excess risks for a variety of circulatory diseases in this dataset, with significant modification of risk by time since exposure. The consistency of the dose-response slopes with those observed in radiotherapeutically treated groups at much higher dose, as well as in lower dose-exposed cohorts such as the Japanese atomic bomb survivors and nuclear workers, implies that there may be little sparing effect of fractionation of dose or low-dose-rate exposure.

  16. Maximal Entanglement in High Energy Physics

    Directory of Open Access Journals (Sweden)

    Alba Cervera-Lierta, José I. Latorre, Juan Rojo, Luca Rottoli

    2017-11-01

    Full Text Available We analyze how maximal entanglement is generated at the fundamental level in QED by studying correlations between helicity states in tree-level scattering processes at high energy. We demonstrate that two mechanisms for the generation of maximal entanglement are at work: i $s$-channel processes where the virtual photon carries equal overlaps of the helicities of the final state particles, and ii the indistinguishable superposition between $t$- and $u$-channels. We then study whether requiring maximal entanglement constrains the coupling structure of QED and the weak interactions. In the case of photon-electron interactions unconstrained by gauge symmetry, we show how this requirement allows reproducing QED. For $Z$-mediated weak scattering, the maximal entanglement principle leads to non-trivial predictions for the value of the weak mixing angle $\\theta_W$. Our results are a first step towards understanding the connections between maximal entanglement and the fundamental symmetries of high-energy physics.

  17. SPECIAL CONSIDERATIONS REGARDING WARFARIN DOSE TITRATION IN PATIENTS WITH ATRIAL FIBRILLATION DEPENDING ON CLINICAL FACTORS

    OpenAIRE

    E. L. Artanova; E. V. Saleeva; I. M. Sokolov; Y. G. Shvarts

    2011-01-01

    Aim. To study the relations of clinical characteristics and individual warfarin dose titration in patients with atrial fibrillation. Material and methods. Period of warfarin dose titration was analyzed in 68 patients with atrial fibrillation due to ischemic heart disease. Adjusted warfarin dose in milligram, duration of dose titration in days and maximal international normalized ratio (INR) were taken into account. Sex, age, history of myocardial infarction and stroke, concomitant diseases, a...

  18. Maximal Inequalities for Dependent Random Variables

    DEFF Research Database (Denmark)

    Hoffmann-Jorgensen, Jorgen

    2016-01-01

    Maximal inequalities play a crucial role in many probabilistic limit theorem; for instance, the law of large numbers, the law of the iterated logarithm, the martingale limit theorem and the central limit theorem. Let X-1, X-2,... be random variables with partial sums S-k = X-1 + ... + X-k. Then a......Maximal inequalities play a crucial role in many probabilistic limit theorem; for instance, the law of large numbers, the law of the iterated logarithm, the martingale limit theorem and the central limit theorem. Let X-1, X-2,... be random variables with partial sums S-k = X-1 + ... + X......-k. Then a maximal inequality gives conditions ensuring that the maximal partial sum M-n = max(1) (...

  19. An ethical justification of profit maximization

    DEFF Research Database (Denmark)

    Koch, Carsten Allan

    2010-01-01

    In much of the literature on business ethics and corporate social responsibility, it is more or less taken for granted that attempts to maximize profits are inherently unethical. The purpose of this paper is to investigate whether an ethical argument can be given in support of profit maximizing...... behaviour. It is argued that some form of consequential ethics must be applied, and that both profit seeking and profit maximization can be defended from a rule-consequential point of view. It is noted, however, that the result does not apply unconditionally, but requires that certain form of profit (and...... utility) maximizing actions are ruled out, e.g., by behavioural norms or formal institutions....

  20. The Physician Tendency in Stereotactic Radiosurgery Dose Prescription in Benign Intracranial Tumor at dr. Cipto Mangunkusumo National Hospital, Jakarta

    Directory of Open Access Journals (Sweden)

    Henry Kodrat

    2016-09-01

    Full Text Available Stereotactic radiosurgery (SRS is one of the treatment modalities for benign intra-cranial tumor, especiallyfor the tumor located next to the critical neural structure. The prescribed dose for radiosurgery depends onthe maximal tumor diameter and surrounding normal tissue tolerance dose. This cross sectional study wasconducted to evaluate the physician’s tendency in radiosurgery dose prescription. We observed treatmentplanning data of 32 patients with benign intra-cranial tumor, which had been treated with SRS at Dr. CiptoMangunkusumo National Hospital in 2009-2010. The peripheral dose, organ at risk (OAR dose limitiationand maximum tumor diameter were recorded. We compared our SRS dose with dose limitation, whichallowed safer dosing based on maximal tumor diameter perspective and the nearest OAR dose constraint.From maximal tumor diameter perspective, we prescribed mean±SD radiosurgery doses, which were11.63±2.21Gy, 10.21±1.29Gy and 9.88±1.07Gy for the tumor size ≤2cm, 2.01-3cm and 3,01-4cm respectively.Our radiosurgery dose was the lowest than dose limitation based on the nearest OAR perspective, followedby maximal tumor diameter perspective. It was concluded that radiosurgery dose had the tendency to beinfluenced by surrounding healthy tissue tolerance rather than maximal tumor diameter. Keywords: stereotactic, radiosurgery, benign tumor, dose.   Kecenderungan Dokter dalam Menentukan Dosis StereotacticRadiosurgery untuk Tumor Jinak Intrakranial diRSUP Nasional dr. Cipto Mangunkusumo, Jakarta Abstrak Stereotactic radiosurgery (SRS merupakan salah satu modalitas pengobatan tumor jinak intra-kranialterutama untuk tumor yang berdekatan dengan struktur saraf penting. Penentuan dosis pada radiosurgerytergantung pada diameter tumor maksimal dan dosis toleransi jaringan sehat sekitarnya. Penelitian inidilakukan untuk mengevaluasi kecenderungan dokter dalam menentukan dosis radiosurgery. Penelitian crosssectional ini mengevaluasi data

  1. Feasibility of TCP-based dose painting by numbers applied to a prostate case with 18F-choline PET imaging

    International Nuclear Information System (INIS)

    Dirscherl, Thomas; Bogner, Ludwig; Rickhey, Mark

    2012-01-01

    Introduction: A biologically adaptive radiation treatment method to maximize the TCP is shown. Functional imaging is used to acquire a heterogeneous dose prescription in terms of Dose Painting by Numbers and to create a patient-specific IMRT plan. Method and Materials: Adapted from a method for selective dose escalation under the guidance of spatial biology distribution, a model, which translates heterogeneously distributed radiobiological parameters into voxelwise dose prescriptions, was developed. At the example of a prostate case with 18 F-choline PET imaging, different sets of reported values for the parameters were examined concerning their resulting range of dose values. Furthermore, the influence of each parameter of the linear-quadratic model was investigated. A correlation between PET signal and proliferation as well as cell density was assumed. Using our in-house treatment planning software Direct Monte Carlo Optimization (DMCO), a treatment plan based on the obtained dose prescription was generated. Gafchromic EBT films were irradiated for evaluation. Results: When a TCP of 95% was aimed at, the maximal dose in a voxel of the prescription exceeded 100 Gy for most considered parameter sets. One of the parameter sets resulted in a dose range of 87.1 Gy to 99.3 Gy, yielding a TCP of 94.7%, and was investigated more closely. The TCP of the plan decreased to 73.5% after optimization based on that prescription. The dose difference histogram of optimized and prescribed dose revealed a mean of -1.64 Gy and a standard deviation of 4.02 Gy. Film verification showed a reasonable agreement of planned and delivered dose. Conclusion: If the distribution of radiobiological parameters within a tumor is known, this model can be used to create a dose-painting by numbers plan which maximizes the TCP. It could be shown, that such a heterogeneous dose distribution is technically feasible. (orig.)

  2. Inclusive Fitness Maximization:An Axiomatic Approach

    OpenAIRE

    Okasha, Samir; Weymark, John; Bossert, Walter

    2014-01-01

    Kin selection theorists argue that evolution in social contexts will lead organisms to behave as if maximizing their inclusive, as opposed to personal, fitness. The inclusive fitness concept allows biologists to treat organisms as akin to rational agents seeking to maximize a utility function. Here we develop this idea and place it on a firm footing by employing a standard decision-theoretic methodology. We show how the principle of inclusive fitness maximization and a related principle of qu...

  3. Does mental exertion alter maximal muscle activation?

    Directory of Open Access Journals (Sweden)

    Vianney eRozand

    2014-09-01

    Full Text Available Mental exertion is known to impair endurance performance, but its effects on neuromuscular function remain unclear. The purpose of this study was to test the hypothesis that mental exertion reduces torque and muscle activation during intermittent maximal voluntary contractions of the knee extensors. Ten subjects performed in a randomized order three separate mental exertion conditions lasting 27 minutes each: i high mental exertion (incongruent Stroop task, ii moderate mental exertion (congruent Stroop task, iii low mental exertion (watching a movie. In each condition, mental exertion was combined with ten intermittent maximal voluntary contractions of the knee extensor muscles (one maximal voluntary contraction every 3 minutes. Neuromuscular function was assessed using electrical nerve stimulation. Maximal voluntary torque, maximal muscle activation and other neuromuscular parameters were similar across mental exertion conditions and did not change over time. These findings suggest that mental exertion does not affect neuromuscular function during intermittent maximal voluntary contractions of the knee extensors.

  4. Assessment of skin dose modification caused by application of immobilizing cast in head and neck radiotherapy

    International Nuclear Information System (INIS)

    Soleymanifard, Shokouhozaman; Toossi, Mohammad T.B.; Khosroabadi, Mohsen; Noghreiyan, Atefeh Vejdani; Shahidsales, Soodabeh; Tabrizi, Fatemeh Varshoee

    2014-01-01

    Skin dose assessment for radiotherapy patients is important to ensure that the dose received by skin is not excessive and does not cause skin reactions. Immobilizing casts may have a buildup effect, and can enhance the skin dose. This study has quantified changes to the surface dose as a result of head and neck immobilizing casts. Medtech and Renfu casts were stretched on the head of an Alderson Rando-Phantom. Irradiation was performed using 6 and 15 MV X-rays, and surface dose was measured by thermoluminescence dosimeters. In the case of 15MV photons, immobilizing casts had no effect on the surface dose. However, the mean surface dose increase reached up to 20 % when 6MV X-rays were applied. Radiation incidence angle, thickness, and meshed pattern of the casts affected the quantity of dose enhancement. For vertical beams, the surface dose increase was more than tangential beams, and when doses of the points under different areas of the casts were analysed separately, results showed that only doses of the points under the thick area had been changed. Doses of the points under the thin area and those within the holes were identical to the same points without immobilizing casts. Higher dose which was incurred due to application of immobilizing casts (20 %) would not affect the quality of life and treatment of patients whose head and neck are treated. Therefore, the benefits of head and neck thermoplastic casts are more than their detriments. However, producing thinner casts with larger holes may reduce the dose enhancement effect.

  5. Ion therapy of prostate cancer: daily rectal dose reduction by application of spacer gel

    International Nuclear Information System (INIS)

    Rucinski, Antoni; Brons, Stephan; Richter, Daniel; Habl, Gregor; Debus, Jürgen; Bert, Christoph; Haberer, Thomas; Jäkel, Oliver

    2015-01-01

    Ion beam therapy represents a promising approach to treat prostate cancer, mainly due to its high conformity and radiobiological effectiveness. However, the presence of prostate motion, patient positioning and range uncertainties may deteriorate target dose and increase exposure of organs at risk. Spacer gel injected between prostate and rectum may increase the safety of prostate cancer (PC) radiation therapy by separating the rectum from the target dose field. The dosimetric impact of the application of spacer gel for scanned carbon ion therapy of PC has been analyzed at Heidelberg Ion-Beam Therapy Center (HIT). The robustness of ion therapy treatment plans was investigated by comparison of two data sets of patients treated with and without spacer gel. A research treatment planning system for ion therapy was used for treatment plan optimization and calculation of daily dose distributions on 2 to 9 Computed Tomography (CT) studies available for each of the 19 patients. Planning and daily dose distributions were analyzed with respect to target coverage, maximal dose to the rectum (excluding 1 ml of the greatest dose; Dmax-1 ml) and the rectal volume receiving dose greater than 90% of prescribed target dose (V90 Rectum ), respectively. The application of spacer gel did substantially diminish rectum dose. Dmax-1 ml on the treatment planning CT was on average reduced from 100.0 ± 1.0% to 90.2 ± 4.8%, when spacer gel was applied. The robustness analysis performed with daily CT studies demonstrated for all analyzed patient cases that application of spacer gel results in a decrease of the daily V90 Rectum index, which calculated over all patient cases and CT studies was 10.2 ± 10.4 [ml] and 1.1 ± 2.1 [ml] for patients without and with spacer gel, respectively. The dosimetric benefit of increasing the distance between prostate and rectum using spacer gel for PC treatment with carbon ion beams has been quantified. Application of spacer gel substantially reduced rectal

  6. On maximal surfaces in asymptotically flat space-times

    International Nuclear Information System (INIS)

    Bartnik, R.; Chrusciel, P.T.; O Murchadha, N.

    1990-01-01

    Existence of maximal and 'almost maximal' hypersurfaces in asymptotically flat space-times is established under boundary conditions weaker than those considered previously. We show in particular that every vacuum evolution of asymptotically flat data for Einstein equations can be foliated by slices maximal outside a spatially compact set and that every (strictly) stationary asymptotically flat space-time can be foliated by maximal hypersurfaces. Amongst other uniqueness results, we show that maximal hypersurface can be used to 'partially fix' an asymptotic Poincare group. (orig.)

  7. Comparison of dose-responses of contact allergens using the guinea pig maximization test and the local lymph node assay

    NARCIS (Netherlands)

    Och, F.M.M. van; Vandebriel, R.J.; Prinsen, M.K.; Jong, W.H. de; Slob, W.; Loveren, H. van

    2001-01-01

    The guinea pig maximization test (GPMT) has been used as a method for the prediction of skin sensitizing potential for over 30 years. Besides hazard identification, risk assessment of sensitizing chemicals requires the assessment of potency. For the determination of potency based on lowest effective

  8. Optimization of the linear induction accelerator construction for maximizing the bremsstrahlung output

    Energy Technology Data Exchange (ETDEWEB)

    Zinchenko, V F; Tulisov, E V; Chlenov, A M; Shiyan, V D [Research Institute of Scientific Instruments, Turaevo-Lytkarino (Russian Federation)

    1997-12-31

    The results of experimental and theoretical optimization of the linear induction accelerator (LIA) design are presented. The major aim of the investigations was to maximize the bremsstrahlung output near the target face. The work was carried out in two stages: l) modernization of the injector module and 2) focusing of the relativistic electron beam (REB) produced at the exit of the accelerating system (AS) in the increasing axial magnetic field. In addition, the methods of diagnostics of angular and energetic parameters of REB based on measurements of radiation dose fields behind the target are described. (author). 2 figs., 4 refs.

  9. Insulin resistance and maximal oxygen uptake

    DEFF Research Database (Denmark)

    Seibaek, Marie; Vestergaard, Henrik; Burchardt, Hans

    2003-01-01

    BACKGROUND: Type 2 diabetes, coronary atherosclerosis, and physical fitness all correlate with insulin resistance, but the relative importance of each component is unknown. HYPOTHESIS: This study was undertaken to determine the relationship between insulin resistance, maximal oxygen uptake......, and the presence of either diabetes or ischemic heart disease. METHODS: The study population comprised 33 patients with and without diabetes and ischemic heart disease. Insulin resistance was measured by a hyperinsulinemic euglycemic clamp; maximal oxygen uptake was measured during a bicycle exercise test. RESULTS......: There was a strong correlation between maximal oxygen uptake and insulin-stimulated glucose uptake (r = 0.7, p = 0.001), and maximal oxygen uptake was the only factor of importance for determining insulin sensitivity in a model, which also included the presence of diabetes and ischemic heart disease. CONCLUSION...

  10. Isotope-beam modification of materials at eV energies

    International Nuclear Information System (INIS)

    Krug, C.; Radtke, C.; Stedile, F.C.; Baumvol, I.J.R.

    2001-01-01

    We developed a low energy ion beam deposition system for isotope-selective modification of materials. It consists of a conventional ion implanter (HVEE 500 kV) and an attachable deceleration system. 29 (N 2 ) + ion beams were used for the nitridation of Si(0 0 1) and the resulting 15 N retained doses and profiles were determined by narrow nuclear resonance profiling. 29 Si was deposited on amorphous carbon films on Si(0 0 1) and the doses evaluated by channeled α particle beams with detection of scattered α at grazing angles. 29 Si was also deposited on Si(0 0 1) and the resulting profiles determined by narrow nuclear resonance

  11. Modification and validation of an analytical source model for external beam radiotherapy Monte Carlo dose calculations

    Energy Technology Data Exchange (ETDEWEB)

    Davidson, Scott E., E-mail: sedavids@utmb.edu [Radiation Oncology, The University of Texas Medical Branch, Galveston, Texas 77555 (United States); Cui, Jing [Radiation Oncology, University of Southern California, Los Angeles, California 90033 (United States); Kry, Stephen; Ibbott, Geoffrey S.; Followill, David S. [Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, Texas 77030 (United States); Deasy, Joseph O. [Department of Medical Physics, Memorial Sloan Kettering Cancer Center, New York, New York 10065 (United States); Vicic, Milos [Department of Applied Physics, University of Belgrade, Belgrade 11000 (Serbia); White, R. Allen [Bioinformatics and Computational Biology, The University of Texas MD Anderson Cancer Center, Houston, Texas 77030 (United States)

    2016-08-15

    Purpose: A dose calculation tool, which combines the accuracy of the dose planning method (DPM) Monte Carlo code and the versatility of a practical analytical multisource model, which was previously reported has been improved and validated for the Varian 6 and 10 MV linear accelerators (linacs). The calculation tool can be used to calculate doses in advanced clinical application studies. One shortcoming of current clinical trials that report dose from patient plans is the lack of a standardized dose calculation methodology. Because commercial treatment planning systems (TPSs) have their own dose calculation algorithms and the clinical trial participant who uses these systems is responsible for commissioning the beam model, variation exists in the reported calculated dose distributions. Today’s modern linac is manufactured to tight specifications so that variability within a linac model is quite low. The expectation is that a single dose calculation tool for a specific linac model can be used to accurately recalculate dose from patient plans that have been submitted to the clinical trial community from any institution. The calculation tool would provide for a more meaningful outcome analysis. Methods: The analytical source model was described by a primary point source, a secondary extra-focal source, and a contaminant electron source. Off-axis energy softening and fluence effects were also included. The additions of hyperbolic functions have been incorporated into the model to correct for the changes in output and in electron contamination with field size. A multileaf collimator (MLC) model is included to facilitate phantom and patient dose calculations. An offset to the MLC leaf positions was used to correct for the rudimentary assumed primary point source. Results: Dose calculations of the depth dose and profiles for field sizes 4 × 4 to 40 × 40 cm agree with measurement within 2% of the maximum dose or 2 mm distance to agreement (DTA) for 95% of the data

  12. POLITENESS MAXIM OF MAIN CHARACTER IN SECRET FORGIVEN

    Directory of Open Access Journals (Sweden)

    Sang Ayu Isnu Maharani

    2017-06-01

    Full Text Available Maxim of Politeness is an interesting subject to be discussed, since politeness has been criticized from our childhood. We are obliques to be polite to anyone either in speaking or in acting. Somehow we are manage to show politeness in our spoken expression though our intention might be not so polite. For example we must appriciate others opinion although we feel objection toward the opinion. In this article the analysis of politeness is based on maxim proposes by Leech. He proposed six types of politeness maxim. The discussion shows that the main character (Kristen and Kami use all types of maxim in their conversation. The most commonly used are approbation maxim and agreement maxim

  13. Major inter-personal variation in the increase and maximal level of 25-hydroxy vitamin D induced by UVB

    DEFF Research Database (Denmark)

    Datta, Pameli; Philipsen, Peter A.; Olsen, Peter

    2016-01-01

    Vitamin D influences skeletal health as well as other aspects of human health. Even when the most obvious sources of variation such as solar UVB exposure, latitude, season, clothing habits, skin pigmentation and ethnicity are selected for, variation in the serum 25-hydroxy vitamin D (25(OH......)D) response to UVB remains extensive and unexplained. Our study assessed the inter-personal variation in 25(OH)D response to UVR and the maximal obtainable 25(OH)D level in 22 healthy participants (220 samples) with similar skin pigmentation during winter with negligible ambient UVB. Participants received...... identical UVB doses on identical body areas until a maximal level of 25(OH)D was reached. Major inter-personal variation in both the maximal obtainable UVB-induced 25(OH)D level (range 85–216 nmol l−1, mean 134 nmol l−1) and the total increase in 25(OH)D (range 3–139 nmol l−1, mean 48 nmol l−1) was found...

  14. Interactive dose shaping - efficient strategies for CPU-based real-time treatment planning

    International Nuclear Information System (INIS)

    Ziegenhein, P; Kamerling, C P; Oelfke, U

    2014-01-01

    Conventional intensity modulated radiation therapy (IMRT) treatment planning is based on the traditional concept of iterative optimization using an objective function specified by dose volume histogram constraints for pre-segmented VOIs. This indirect approach suffers from unavoidable shortcomings: i) The control of local dose features is limited to segmented VOIs. ii) Any objective function is a mathematical measure of the plan quality, i.e., is not able to define the clinically optimal treatment plan. iii) Adapting an existing plan to changed patient anatomy as detected by IGRT procedures is difficult. To overcome these shortcomings, we introduce the method of Interactive Dose Shaping (IDS) as a new paradigm for IMRT treatment planning. IDS allows for a direct and interactive manipulation of local dose features in real-time. The key element driving the IDS process is a two-step Dose Modification and Recovery (DMR) strategy: A local dose modification is initiated by the user which translates into modified fluence patterns. This also affects existing desired dose features elsewhere which is compensated by a heuristic recovery process. The IDS paradigm was implemented together with a CPU-based ultra-fast dose calculation and a 3D GUI for dose manipulation and visualization. A local dose feature can be implemented via the DMR strategy within 1-2 seconds. By imposing a series of local dose features, equal plan qualities could be achieved compared to conventional planning for prostate and head and neck cases within 1-2 minutes. The idea of Interactive Dose Shaping for treatment planning has been introduced and first applications of this concept have been realized.

  15. Modification of radiation-induced murine thymic lymphoma incidence by curcumin

    International Nuclear Information System (INIS)

    Dange, P.S.; Yadav, H.D.; Kumar, Vimalesh; Bhilwade, H.N.; Pandey, B.N.; Sarma, H.D.

    2017-01-01

    Curcumin is a known antioxidant, preventing radiation damage including carcinogenesis. However, concentration and feeding schedule of curcumin in modification of radiation induced thymic lymphoma incidence in vivo model has not been studied. We report here modification of incidence of γ-radiation-induced thymic lymphoma in mice fed with different doses of curcumin (0.05 to 1 %) in diet. Results: Female Swiss mice (6-8 weeks) fed with normal diet and exposed to 3 Gy whole body "6"0Co γ-irradiation (WBI) showed 85 % incidence of thymic lymphoma (TL) at 120 days post-irradiation. A concentration of 1 % curcumin was found the most effective in TL incidence prevention than other fed concentrations. The TL incidence was remarkably reduced when curcumin was fed to the mice before than after the radiation exposure. These results suggest modification of TL incidence by curcumin in irradiated mice involving DNA damage and apoptotic death mechanisms

  16. Serum level modifications of female sex hormones after radiocastration with different total doses

    International Nuclear Information System (INIS)

    Naujokat, B.; Rohloff, R.; Willich, N.; Eiermann, W.

    1988-01-01

    We determined serum level of estradiol, FSH and LH over a period of six to eight weeks after ovarian irradiation for castration with different doses (2x2.5 Gy/3x2.5 Gy/4x2.5 Gy) in 15 patients with metastatic breast cancer as compared to changes after ovarectomy in five patients. The time course of the changing estradiol-, FSH and LH-serum levels sigificantly depends on the ovarian dose. After radiological castration with a dose of 4x2.5 Gy = 10 Gy in four days the estrogen levels decrease within two to three weeks, and the FSH- and LH-levels increase after three to four weeks into the postmenopausal range. Therefore, the time course is not very different from changes after ovarectomy. (orig.) [de

  17. Investigation of dose modifications related to dental cares in an ORL radiotherapy treatment

    International Nuclear Information System (INIS)

    De Conto, C.; Gschwind, R.; Makovicka, L.; De Conto, C.; Martin, E.

    2010-01-01

    The authors report the investigation of the influence of dental implants on the dose received during an ORL radiotherapy treatment in order to optimize both the dosimetric planning and the patient radioprotection. They report experimental measurements performed on a phantom representing a lower jaw in irradiation conventional conditions. Then, they report the Monte Carlo simulation of the dose distribution in the phantom using the BEAMnrc code designed for radiotherapy

  18. Maximization of Egyptian Gas Oil Production Through the Optimal Use of the Operating Parameters

    International Nuclear Information System (INIS)

    Marawan, H.

    2004-01-01

    Gas oil is the major fossil fuel consumed around the world. Global gas oil consumption is rising at a steadily fast pace because of its higher combustion efficiency (versus gasoline). The annual increase rate of gas oil consumption in Egypt is 7 % whereas, the world increase rates range from 1.5 % to 2 % . The main sources for producing gas oil in Egypt refiners is the direct production from the atmospheric distillation process units or it may be produced as a side product from vacuum distillation units . Gas oil is produced through hydrocracking process of vacuum distillation side streams and heavy cocked gas oil. Gas oil production yield can be increased through the existing operation process units. Modifications of the current atmospheric and vacuum tower operations will increase gas oil yield rates to 20 % more than the existing production rates. The modification of the operating conditions and adoption of the optimum catalyst of the existing hydrocracking and mild hydro cracking process units improve gas oil production yield. Operating delayed cocker at high temperatures, low pressure and low cycle ratio also support achieving the maximization of gas oil yield

  19. Natural maximal νμ-ντ mixing

    International Nuclear Information System (INIS)

    Wetterich, C.

    1999-01-01

    The naturalness of maximal mixing between myon- and tau-neutrinos is investigated. A spontaneously broken nonabelian generation symmetry can explain a small parameter which governs the deviation from maximal mixing. In many cases all three neutrino masses are almost degenerate. Maximal ν μ -ν τ -mixing suggests that the leading contribution to the light neutrino masses arises from the expectation value of a heavy weak triplet rather than from the seesaw mechanism. In this scenario the deviation from maximal mixing is predicted to be less than about 1%. (Copyright (c) 1999 Elsevier Science B.V., Amsterdam. All rights reserved.)

  20. Gaussian maximally multipartite-entangled states

    Science.gov (United States)

    Facchi, Paolo; Florio, Giuseppe; Lupo, Cosmo; Mancini, Stefano; Pascazio, Saverio

    2009-12-01

    We study maximally multipartite-entangled states in the context of Gaussian continuous variable quantum systems. By considering multimode Gaussian states with constrained energy, we show that perfect maximally multipartite-entangled states, which exhibit the maximum amount of bipartite entanglement for all bipartitions, only exist for systems containing n=2 or 3 modes. We further numerically investigate the structure of these states and their frustration for n≤7 .

  1. Gaussian maximally multipartite-entangled states

    International Nuclear Information System (INIS)

    Facchi, Paolo; Florio, Giuseppe; Pascazio, Saverio; Lupo, Cosmo; Mancini, Stefano

    2009-01-01

    We study maximally multipartite-entangled states in the context of Gaussian continuous variable quantum systems. By considering multimode Gaussian states with constrained energy, we show that perfect maximally multipartite-entangled states, which exhibit the maximum amount of bipartite entanglement for all bipartitions, only exist for systems containing n=2 or 3 modes. We further numerically investigate the structure of these states and their frustration for n≤7.

  2. Utility maximization and mode of payment

    NARCIS (Netherlands)

    Koning, R.H.; Ridder, G.; Heijmans, R.D.H.; Pollock, D.S.G.; Satorra, A.

    2000-01-01

    The implications of stochastic utility maximization in a model of choice of payment are examined. Three types of compatibility with utility maximization are distinguished: global compatibility, local compatibility on an interval, and local compatibility on a finite set of points. Keywords:

  3. Modification of transmission dose algorithm for irregularly shaped radiation field and tissue deficit

    Energy Technology Data Exchange (ETDEWEB)

    Yun, Hyong Geon; Shin, Kyo Chul [Dankook Univ., College of Medicine, Seoul (Korea, Republic of); Huh, Soon Nyung; Woo, Hong Gyun; Ha, Sung Whan [Seoul National Univ., College of Medicine, Seoul (Korea, Republic of); Lee, Hyoung Koo [The Catholic Univ., College of Medicine, Seoul (Korea, Republic of)

    2002-07-01

    Algorithm for estimation of transmission dose was modified for use in partially blocked radiation fields and in cases with tissue deficit. The beam data was measured with flat solid phantom in various conditions of beam block. And an algorithm for correction of transmission dose in cases of partially blocked radiation field was developed from the measured data. The algorithm was tested in some clinical settings with irregular shaped field. Also, another algorithm for correction of transmission dose for tissue deficit was developed by physical reasoning. This algorithm was tested in experimental settings with irregular contours mimicking breast cancer patients by using multiple sheets of solid phantoms. The algorithm for correction of beam block could accurately reflect the effect of beam block, with error within {+-}1.0%, both with square fields and irregularly shaped fields. The correction algorithm for tissue deficit could accurately reflect the effect of tissue deficit with errors within {+-}1.0% in most situations and within {+-}3.0% in experimental settings with irregular contours mimicking breast cancer treatment set-up. Developed algorithms could accurately estimate the transmission dose in most radiation treatment settings including irregularly shaped field and irregularly shaped body contour with tissue deficit in transmission dosimetry.

  4. Modification of transmission dose algorithm for irregularly shaped radiation field and tissue deficit

    International Nuclear Information System (INIS)

    Yun, Hyong Geon; Shin, Kyo Chul; Huh, Soon Nyung; Woo, Hong Gyun; Ha, Sung Whan; Lee, Hyoung Koo

    2002-01-01

    Algorithm for estimation of transmission dose was modified for use in partially blocked radiation fields and in cases with tissue deficit. The beam data was measured with flat solid phantom in various conditions of beam block. And an algorithm for correction of transmission dose in cases of partially blocked radiation field was developed from the measured data. The algorithm was tested in some clinical settings with irregular shaped field. Also, another algorithm for correction of transmission dose for tissue deficit was developed by physical reasoning. This algorithm was tested in experimental settings with irregular contours mimicking breast cancer patients by using multiple sheets of solid phantoms. The algorithm for correction of beam block could accurately reflect the effect of beam block, with error within ±1.0%, both with square fields and irregularly shaped fields. The correction algorithm for tissue deficit could accurately reflect the effect of tissue deficit with errors within ±1.0% in most situations and within ±3.0% in experimental settings with irregular contours mimicking breast cancer treatment set-up. Developed algorithms could accurately estimate the transmission dose in most radiation treatment settings including irregularly shaped field and irregularly shaped body contour with tissue deficit in transmission dosimetry

  5. Modification of biomolecules and combined actions by radiation

    International Nuclear Information System (INIS)

    Kim, Jin Kyu; Lee, J. W.; Kim, J. H.; Choi, J. I.; Song, B. S.; Kim, J. K.; Park, J. H.; Lee, Y. J.; Ryu, S. H.; Sung, N. Y.; Cha, M. K.; Nam, J. Y.; Park, J. Y.; Cho, E. R.; Ryu, T. H.

    2011-12-01

    Advanced Radiation Technology Institute is a government-supported institute for radiation research and application. It has focused on development of fundamentals for radiation applications based on the existing radiation technology, and on enhancement of biological effectiveness of radiation through theoretical approach to the combined actions of radiation with another factor. Application of radiation technology together with the existing technologies to enhance the physical, chemical, biological characteristics through modification of biomolecules resulted in creation of de novo materials of scientific and industrial values. A theoretical model for combined action of radiation with another physico-chemical factor has been established. Conclusively the results of this study can provide scientific bases for maximizing the efficacy of ionizing radiation in relation to industrial applications

  6. Gamma irradiation effect on soy protein modification, protein - phenolic interaction and antioxidant activity in soybean

    International Nuclear Information System (INIS)

    Kumari, Sweta; Dahuja, Anil; Vinutha, T.; Singh, Bhupinder

    2014-01-01

    Soy protein is one of the most important sources of protein to feed the world population in the future. Consumption of soybean quality protein and their texture is dependent on the protein modification. In the present study, four soybean genotypes PL5039 (black), EC 472143 (black), Pusa 9814 (yellow) and SL525 (yellow), differing in their seed coat colour were gamma irradiated at 0.5,1.0, 2.0 and 5.0 kGy and the extent of protein modification and parameters affecting it viz. free phenolics, bound phenolics, lip oxygenase and antioxidant activity were analysed. Modifications of soybean proteins were investigated by chemical analysis and electrophoresis. The irradiation dose of 1.0 kGy showed decreased turbidity, protein oxidation, surface hydrophobicity but increased solubility and sulfhydryl and disulfide contents in all the genotypes. Further, SDS PAGE profile of treated soybean seeds revealed remarkable difference in electrophoretic bands as compared to the untreated seeds. Lipoxygense activity in all the genotypes decreased with increased exposure of gamma irradiation, which produced peroxide products that changes the structural characteristics of soy protein. Free phenolics, bound phenolics and total antioxidant activity measured in terms of FRAP in all the genotypes increased significantly at a dose of 2.0 kGy and it declined at a dose of 5.0 kGy. Antioxidant potential measured in terms of 1,1-diphenyl-2- picrylhydrazyl (DPPH) scavenging activity showed an increasing trend with dose, indicating that radiation processing as a method of food preservation has a positive nutritional implication. Hence, it is suggested that, mild gamma irradiation upto 2.0 kGy may reduce the protein oxidation, enhance the antioxidant activity and improve the soybean protein quality compared to higher dose 5.0 kGy, which reduced the protein quality. (author)

  7. Planning of occupational dose reduction at BWR power plant by past dose record analysis combined with on-site workers' idea analysis

    International Nuclear Information System (INIS)

    Konno, T.; Taira, J.; Hayashida, T.; Suzuki, A.; Hayashi, K.; Kato, S.; Ishikawa, T.; Konno, T.; Hayashi, K.

    2011-01-01

    In order to establish a plan for occupational dose reduction at operating plants, outage inspection works that involve high-dose exposure were selected and a determination of the major causes of high-dose exposure made by plant-by-plant comparison of doses received during inspection works. The comparison was made to investigate the relationship between exposure and the volume of objects to be inspected, working time and man-hour of each work process and ambient dose rates at work areas. In parallel with this, an analysis has also been carried out on 400 data items in a questionnaire survey conducted on relevant individuals, including foremen, radiation safety personnel, on-site workers and plant designers regarding ideas for dose reduction methods. With combination of these two analyses, matters that require improvement will be highlighted, then modification of equipment or revision of work procedures necessary for occupational dose reduction will be planned by plant designers through review. (authors)

  8. Activity versus outcome maximization in time management.

    Science.gov (United States)

    Malkoc, Selin A; Tonietto, Gabriela N

    2018-04-30

    Feeling time-pressed has become ubiquitous. Time management strategies have emerged to help individuals fit in more of their desired and necessary activities. We provide a review of these strategies. In doing so, we distinguish between two, often competing, motives people have in managing their time: activity maximization and outcome maximization. The emerging literature points to an important dilemma: a given strategy that maximizes the number of activities might be detrimental to outcome maximization. We discuss such factors that might hinder performance in work tasks and enjoyment in leisure tasks. Finally, we provide theoretically grounded recommendations that can help balance these two important goals in time management. Published by Elsevier Ltd.

  9. Radiation dose-response relationship of micronucleus occurrence in pollen mother cells of tradescantia

    International Nuclear Information System (INIS)

    Kim, Jin Kyu; Kim, Yeon Ku; Song, Hi Sup

    1999-01-01

    This study was carried out to investigate the radiation dose-response of micronucleus frequencies in Tradescantia pollen mother cells. The number of micronuclei increased in the tetrads as a result of chromosome deletion after irradiation. The maximal frequency of micronucleus showed a good dose-response relationship in the range of dose 0∼50 cGy. On the basis of the relationship, a dose of 1 cGy resulted in two additional micronuclei in 100 tetrads. The radiation dose-response relationship of micronucleus occurrence is prerequisite to biological monitoring of radiation and can be modified for biological risk assessment of toxicants, and to safety test of water or soil integrity

  10. Maximizing Entropy over Markov Processes

    DEFF Research Database (Denmark)

    Biondi, Fabrizio; Legay, Axel; Nielsen, Bo Friis

    2013-01-01

    The channel capacity of a deterministic system with confidential data is an upper bound on the amount of bits of data an attacker can learn from the system. We encode all possible attacks to a system using a probabilistic specification, an Interval Markov Chain. Then the channel capacity...... as a reward function, a polynomial algorithm to verify the existence of an system maximizing entropy among those respecting a specification, a procedure for the maximization of reward functions over Interval Markov Chains and its application to synthesize an implementation maximizing entropy. We show how...... to use Interval Markov Chains to model abstractions of deterministic systems with confidential data, and use the above results to compute their channel capacity. These results are a foundation for ongoing work on computing channel capacity for abstractions of programs derived from code....

  11. Maximizing entropy over Markov processes

    DEFF Research Database (Denmark)

    Biondi, Fabrizio; Legay, Axel; Nielsen, Bo Friis

    2014-01-01

    The channel capacity of a deterministic system with confidential data is an upper bound on the amount of bits of data an attacker can learn from the system. We encode all possible attacks to a system using a probabilistic specification, an Interval Markov Chain. Then the channel capacity...... as a reward function, a polynomial algorithm to verify the existence of a system maximizing entropy among those respecting a specification, a procedure for the maximization of reward functions over Interval Markov Chains and its application to synthesize an implementation maximizing entropy. We show how...... to use Interval Markov Chains to model abstractions of deterministic systems with confidential data, and use the above results to compute their channel capacity. These results are a foundation for ongoing work on computing channel capacity for abstractions of programs derived from code. © 2014 Elsevier...

  12. Electron beam induced modification of poly(ethylene terephthalate) films

    International Nuclear Information System (INIS)

    Vasiljeva, I.V.; Mjakin, S.V.; Makarov, A.V.; Krasovsky, A.N.; Varlamov, A.V.

    2006-01-01

    Electron beam processing of poly(ethylene terephthalate) (PET) films is found to promote significant changes in the melting heat, intrinsic viscosity and polymer film-liquid (water, isooctane and toluene) boundary surface tension. These properties are featured with several maximums depending on the absorbed dose and correlating with the modification of PET surface functionality. Studies using adsorption of acid-base indicators and IR-spectroscopy revealed that the increase of PET surface hydrophilicity is determined by the oxidation of methylene and methyne groups. Electron beam treatment of PET films on the surface of N-vinylpyrrolidone aqueous solution provided graft copolymerization with this comonomer at optimum process parameters (energy 700 keV, current 1 mA, absorbed dose 50 kGy)

  13. Electron beam induced modification of poly(ethylene terephthalate) films

    Energy Technology Data Exchange (ETDEWEB)

    Vasiljeva, I.V. [Technology Center RADIANT, 10, Kurchatova Str., 194223 St. Petersburg (Russian Federation)]. E-mail: radiant@skylink.spb.ru; Mjakin, S.V. [Technology Center RADIANT, 10, Kurchatova Str., 194223 St. Petersburg (Russian Federation); Makarov, A.V. [St.-Petersburg State University of Cinema and Television, 13, ul. Pravdy, 191126 St. Petersburg (Russian Federation); Krasovsky, A.N. [St.-Petersburg State University of Cinema and Television, 13, ul. Pravdy, 191126 St. Petersburg (Russian Federation); Varlamov, A.V. [St.-Petersburg State University of Cinema and Television, 13, ul. Pravdy, 191126 St. Petersburg (Russian Federation)

    2006-10-15

    Electron beam processing of poly(ethylene terephthalate) (PET) films is found to promote significant changes in the melting heat, intrinsic viscosity and polymer film-liquid (water, isooctane and toluene) boundary surface tension. These properties are featured with several maximums depending on the absorbed dose and correlating with the modification of PET surface functionality. Studies using adsorption of acid-base indicators and IR-spectroscopy revealed that the increase of PET surface hydrophilicity is determined by the oxidation of methylene and methyne groups. Electron beam treatment of PET films on the surface of N-vinylpyrrolidone aqueous solution provided graft copolymerization with this comonomer at optimum process parameters (energy 700 keV, current 1 mA, absorbed dose 50 kGy)

  14. Modification of parotids in case of conformal ORL irradiation

    International Nuclear Information System (INIS)

    Louvel, G.; Lafond, C.; Manens, J.P.; Jouyaux, F.; Williaume, D.; Le Prise, E.; Crevoisier, R. de; Cazoulat, G.; Simon, A.; Haigron, P.

    2009-01-01

    The objective of the study is to analyze the anatomical modifications of the parotids in case of tumors irradiation of the O.R.L. area. In case of irradiation of the O.R.L. area the parotids reduce about one third of their volume, by moving inwards and backwards. The dose received by these glands at the end of irradiation can be different from this one initially planned. (N.C.)

  15. HEALTH INSURANCE: CONTRIBUTIONS AND REIMBURSEMENT MAXIMAL

    CERN Document Server

    HR Division

    2000-01-01

    Affected by both the salary adjustment index on 1.1.2000 and the evolution of the staff members and fellows population, the average reference salary, which is used as an index for fixed contributions and reimbursement maximal, has changed significantly. An adjustment of the amounts of the reimbursement maximal and the fixed contributions is therefore necessary, as from 1 January 2000.Reimbursement maximalThe revised reimbursement maximal will appear on the leaflet summarising the benefits for the year 2000, which will soon be available from the divisional secretariats and from the AUSTRIA office at CERN.Fixed contributionsThe fixed contributions, applicable to some categories of voluntarily insured persons, are set as follows (amounts in CHF for monthly contributions):voluntarily insured member of the personnel, with complete coverage:815,- (was 803,- in 1999)voluntarily insured member of the personnel, with reduced coverage:407,- (was 402,- in 1999)voluntarily insured no longer dependent child:326,- (was 321...

  16. On the maximal diphoton width

    CERN Document Server

    Salvio, Alberto; Strumia, Alessandro; Urbano, Alfredo

    2016-01-01

    Motivated by the 750 GeV diphoton excess found at LHC, we compute the maximal width into $\\gamma\\gamma$ that a neutral scalar can acquire through a loop of charged fermions or scalars as function of the maximal scale at which the theory holds, taking into account vacuum (meta)stability bounds. We show how an extra gauge symmetry can qualitatively weaken such bounds, and explore collider probes and connections with Dark Matter.

  17. Interaction of low-dose irradiation with subsequent mutagenic treatment. Role of mitotic delay

    International Nuclear Information System (INIS)

    Salone, B.; Pretazzoli, V.; Bosi, A.; Olivieri, G.

    1996-01-01

    Experiments were carried out with human lymphocytes to test whether there was any relation between the changes that conditioning treatment can produce in cell progression or in mitotic delay induced by the challenge dose and the presence of an 'adaptive response' (AR). In experiments in which the cells were successively fixed after the challenge dose, the interaction between conditioning treatment and challenge was of the same sign for all the fixation times: therefore it is likely that modifications of the cytogenetic damage in primed cells is not a mere reflection of stage sensitivity. In experiments in which using 1 Gy as conditioning treatment we induced a drastic extension of G 2 , we did not observe any AR; therefore, even if conditioning treatment can induce modifications in the cell-cycle phases before and/or after challenge, there is probably no link between these modifications and the presence of an AR

  18. Comparison of equations for dosing of medications in renal impairment.

    Science.gov (United States)

    Khanal, Aarati; Peterson, Gregory M; Jose, Matthew D; Castelino, Ronald L

    2017-06-01

    The aim of this study is to determine the concordance among the Cockcroft-Gault, the Modification of Diet in Renal Disease and the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equations in hypothetical dosing of renally cleared medications. A total of 2163 patients prescribed at least one of the 31 renally cleared drugs under review were included in the study. Kidney function was estimated using the three equations. We compared actual prescribed dosages of the same drug with recommended dosages based on the kidney function as calculated by each of the equations and applying dosing recommendations in the Australian Medicines Handbook. There was a significant difference in the kidney function values estimated from the three equations (P < 0.001). Despite the good overall agreement in renal drug dosing, we found selected but potentially important discrepancies among the doses rendered from the equations. The CKD-EPI equation non-normalized for body surface area had a greater rate of concordance with the Cockcroft-Gault equation than the Modification of Diet in Renal Disease equation for renal drug dosing. There is need for a long-term multi-centre study in a diverse population to define the clinical effects of the discrepancies among the equations for drug dosing. Given the greater concordance of the non-normalized CKD-EPI equation with the Cockcroft-Gault equation for dosing, the recommendation by Kidney Health Australia and the United States National Kidney Disease Education Program that 'dosing based on either eCrCl or an eGFR with body surface area normalization removed are acceptable' seems suitable and practicable for the purpose of dosing of non-critical drugs in the primary care setting. © 2016 Asian Pacific Society of Nephrology.

  19. Shielding modification design of the N.S. Mutsu

    International Nuclear Information System (INIS)

    Yamaji, A.; Miyakoshi, J.; Kageyama, T.; Futamura, Y.

    1983-01-01

    Shielding modification design of the N.S. Mutsu was performed for reducing the radiation doses outside the primary and the secondary shields by providing shields for neutrons streaming through the air gap between the pressure vessel and the primary shield. This was accomplished by replacing parts of the shields and adding new shields in the upper and lower sections of both primary and secondary shields, and also replacing the thermal insulator in the gap. The shielding design calculations were made using one- and two-dimensional discrete ordinates codes and also a point kernel code. Special attention was paid to the calculations of, (1) the neutrons streaming through the gap between the pressure vessel and the primary shield, (2) the radiations transmitted through the radial shield of the core in the primary shield, (3) the radiations transmitted through the upper and lower sections of the secondary shield, and (4) the dose rate equivalent in the accommodation area. Their calculational accuracies were estimated by analyzing various experiments. To support the modification, a variety of experiments and tests were carried out, which were material tests, cooling test of the primary shield, mechanical strength test of the double bottom, trial fabrication tests of new shields, performance degradation test of heavy concrete and duct streaming experiment in the secondary shield. (author)

  20. Implications of dose limit modification for radioactive installations dedicated to research

    International Nuclear Information System (INIS)

    Lumbreras, J.M.; Fernandez, G.M.; Marana, D.

    1992-01-01

    The reduced dose limits proposed in the ICRP recommendations affect the Spanish Regulations on Sanitary Protection against Ionizing Radiation. Some implications of this for radioactive installations dedicated to research are pointed out. A very simple statistical study shows that dosimetric data might be used to adopt new criteria for classification of personnel, and even of working areas. (author)

  1. Modifications of the hydriding kinetics of a metallic surface, using ion implantation

    International Nuclear Information System (INIS)

    Crusset, D.

    1992-10-01

    Uranium reacts with hydrogen to form an hydride: this reaction leads to the total destruction of the material. To modify the reactivity of an uranium surface towards hydrogen, ion implantation was selected, among surface treatments techniques. Four elements (carbon, nitrogen, oxygen, sulfur) were implanted to different doses. The results show a modification of the hydriding mechanism and a significant increase in the reaction induction times, notably at high implantation doses. Several techniques (SIMS, X-rays phases analysis and residual stresses determination) were used to characterize the samples and understand the different mechanisms involved

  2. High-dose inhaled terbutaline increases muscle strength and enhances maximal sprint performance in trained men

    DEFF Research Database (Denmark)

    Hostrup, Morten; Kalsen, Anders; Bangsbo, Jens

    2014-01-01

    ) participated in a double-blinded randomized crossover study. After administration of inhaled terbutaline (30 × 0.5 mg) or placebo, subjects' maximal voluntary isometric contraction (MVC) of m.quadriceps was measured. After MVC, subjects performed a 30-s Wingate test. Sixty minutes following the Wingate test......, subjects exercised for 10 min at 80 % of [Formula: see text] and completed a 100-kcal time trial. Aerobic contribution was determined during the Wingate test by indirect calorimetry. Furthermore, plasma terbutaline, lactate, glucose, and K(+) were measured. RESULTS: Inhalation of 15 mg terbutaline resulted...... = 0.019) and 3.3 ± 1.0 % (P = 0.009) higher for terbutaline than placebo. Net accumulation of plasma lactate was higher (P = 0.003) for terbutaline than placebo during the Wingate test, whereas [Formula: see text] above baseline was unchanged by terbutaline (P = 0.882). Time-trial performance...

  3. Surface modification of ceramics and metals by ion implantation combined with plasma irradiation

    International Nuclear Information System (INIS)

    Miyagawa, Soji; Miyagawa, Yoshiko; Nakao, Setsuo; Ikeyama, Masami; Saitoh, Kazuo

    2000-01-01

    To develop a new surface modification technique using ion implantation combined with plasma irradiation, thin film formation by IBAD (Ion Beam Assisted Deposition) and atom relocation processes such as radiation enhanced diffusion and ion beam mixing under high dose implantation have been studied. It was confirmed that the computer simulation code, dynamic-SASAMAL (IBAD version) developed in this research, is quite useful to evaluate ballistic components in film formation by high dose implantation on ceramics and metals, by ion beam mixing of metal-ceramics bi-layer and by the IBAD method including hydrocarbon deposition. Surface modification process of SiC by simultaneous irradiation of ions with a radical beam has also been studied. A composite of SiC and β-Si 3 N 4 was found to be formed on a SiC surface by hot implantation of nitrogen. The amount of β- Si 3 N 4 crystallites increased with increasing the dosage of the hydrogen radical beam during nitrogen implantation. (author)

  4. Maximizing in vivo target clearance by design of pH-dependent target binding antibodies with altered affinity to FcRn.

    Science.gov (United States)

    Yang, Danlin; Giragossian, Craig; Castellano, Steven; Lasaro, Marcio; Xiao, Haiguang; Saraf, Himanshu; Hess Kenny, Cynthia; Rybina, Irina; Huang, Zhong-Fu; Ahlberg, Jennifer; Bigwarfe, Tammy; Myzithras, Maria; Waltz, Erica; Roberts, Simon; Kroe-Barrett, Rachel; Singh, Sanjaya

    2017-10-01

    Antibodies with pH-dependent binding to both target antigens and neonatal Fc receptor (FcRn) provide an alternative tool to conventional neutralizing antibodies, particularly for therapies where reduction in antigen level is challenging due to high target burden. However, the requirements for optimal binding kinetic framework and extent of pH dependence for these antibodies to maximize target clearance from circulation are not well understood. We have identified a series of naturally-occurring high affinity antibodies with pH-dependent target binding properties. By in vivo studies in cynomolgus monkeys, we show that pH-dependent binding to the target alone is not sufficient for effective target removal from circulation, but requires Fc mutations that increase antibody binding to FcRn. Affinity-enhanced pH-dependent FcRn binding that is double-digit nM at pH 7.4 and single-digit nM at pH 6 achieved maximal target reduction when combined with similar target binding affinities in reverse pH directions. Sustained target clearance below the baseline level was achieved 3 weeks after single-dose administration at 1.5 mg/kg. Using the experimentally derived mechanistic model, we demonstrate the essential kinetic interplay between target turnover and antibody pH-dependent binding during the FcRn recycling, and identify the key components for achieving maximal target clearance. These results bridge the demand for improved patient dosing convenience with the "know-how" of therapeutic modality by design.

  5. Dosing of cytotoxic chemotherapy: impact of renal function estimates on dose.

    Science.gov (United States)

    Dooley, M J; Poole, S G; Rischin, D

    2013-11-01

    Oncology clinicians are now routinely provided with an estimated glomerular filtration rate on pathology reports whenever serum creatinine is requested. The utility of using this for the dose determination of renally excreted drugs compared with other existing methods is needed to inform practice. Renal function was determined by [Tc(99m)]DTPA clearance in adult patients presenting for chemotherapy. Renal function was calculated using the 4-variable Modification of Diet in Renal Disease (4v-MDRD), Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI), Cockcroft and Gault (CG), Wright and Martin formulae. Doses for renal excreted cytotoxic drugs, including carboplatin, were calculated. The concordance of the renal function estimates according to the CKD classification with measured Tc(99m)DPTA clearance in 455 adults (median age 64.0 years: range 17-87 years) for the 4v-MDRD, CKD-EPI, CG, Martin and Wright formulae was 47.7%, 56.3%, 46.2%, 56.5% and 60.2%, respectively. Concordance for chemotherapy dose for these formulae was 89.0%, 89.5%, 85.1%, 89.9% and 89.9%, respectively. Concordance for carboplatin dose specifically was 66.4%, 71.4%, 64.0%, 73.8% and 73.2%. All bedside formulae provide similar levels of concordance in dosage selection for the renal excreted chemotherapy drugs when compared with the use of a direct measure of renal function.

  6. Aging of magnesium stearate under high doses gamma irradiation and oxidative conditions

    Energy Technology Data Exchange (ETDEWEB)

    Lebeau, D.; Beuvier, L.; Cornaton, M. [CEA, DEN, DPC, SECR, LRMO, F-91191 Gif-sur-Yvette (France); Miserque, F. [CEA, DEN, DPC, SCCME, LECA, F-91191 Gif-sur-Yvette (France); Tabarant, M. [CEA, DEN, DPC, SEARS, LISL, F-91191 Gif-sur-Yvette (France); Esnouf, S. [CEA, DEN, DPC, SECR, LRMO, F-91191 Gif-sur-Yvette (France); Ferry, M., E-mail: muriel.ferry@cea.fr [CEA, DEN, DPC, SECR, LRMO, F-91191 Gif-sur-Yvette (France)

    2015-05-15

    Highlights: • Magnesium stearate was radio-oxidized at very high doses using gamma-rays. • H{sub 2} emission was estimated as a function of the integrated dose. • Modifications in the organic solid were followed as a function of the integrated dose. • A non-exhaustive degradation mechanism of magnesium stearate was proposed. - Abstract: In nuclear waste packages conditioning processes, magnesium stearate is widely used because of its high lubricating properties. For safety purposes, the radiolytic degradation of these organic materials has to be better understood to be able to predict their aging in repository conditions. This study reports the radiolytic degradation of magnesium stearate, using gamma-rays at room temperature and under air. Modifications were followed using different analytical tools (XPS, ATR-FTIR, ICP-AES, ATG and mass spectrometry). It has been observed that molecules mainly formed up to 1000 kGy of gamma irradiation dose under radio-oxidation are alkanes, hydroperoxides, double bonds in the aliphatic chain, carboxylates with aliphatic chain shorter than the one of stearate and ketones. At a dose of 4000 kGy, dicarboxylic acids are observed: the formation of these molecules needs a dose of at least 1000 kGy to be created under radio-oxidation. These observations allow us to propose a non-exhaustive degradation mechanism of magnesium stearate under gamma-irradiation at room temperature and under air.

  7. Patient Dose From Megavoltage Computed Tomography Imaging

    International Nuclear Information System (INIS)

    Shah, Amish P.; Langen, Katja M.; Ruchala, Kenneth J.; Cox, Andrea; Kupelian, Patrick A.; Meeks, Sanford L.

    2008-01-01

    Purpose: Megavoltage computed tomography (MVCT) can be used daily for imaging with a helical tomotherapy unit for patient alignment before treatment delivery. The purpose of this investigation was to show that the MVCT dose can be computed in phantoms, and further, that the dose can be reported for actual patients from MVCT on a helical tomotherapy unit. Methods and Materials: An MVCT beam model was commissioned and verified through a series of absorbed dose measurements in phantoms. This model was then used to retrospectively calculate the imaging doses to the patients. The MVCT dose was computed for five clinical cases: prostate, breast, head/neck, lung, and craniospinal axis. Results: Validation measurements in phantoms verified that the computed dose can be reported to within 5% of the measured dose delivered at the helical tomotherapy unit. The imaging dose scaled inversely with changes to the CT pitch. Relative to a normal pitch of 2.0, the organ dose can be scaled by 0.67 and 2.0 for scans done with a pitch of 3.0 and 1.0, respectively. Typical doses were in the range of 1.0-2.0 cGy, if imaged with a normal pitch. The maximal organ dose calculated was 3.6 cGy in the neck region of the craniospinal patient, if imaged with a pitch of 1.0. Conclusion: Calculation of the MVCT dose has shown that the typical imaging dose is approximately 1.5 cGy per image. The uniform MVCT dose delivered using helical tomotherapy is greatest when the anatomic thickness is the smallest and the pitch is set to the lowest value

  8. A Criterion to Identify Maximally Entangled Four-Qubit State

    International Nuclear Information System (INIS)

    Zha Xinwei; Song Haiyang; Feng Feng

    2011-01-01

    Paolo Facchi, et al. [Phys. Rev. A 77 (2008) 060304(R)] presented a maximally multipartite entangled state (MMES). Here, we give a criterion for the identification of maximally entangled four-qubit states. Using this criterion, we not only identify some existing maximally entangled four-qubit states in the literature, but also find several new maximally entangled four-qubit states as well. (general)

  9. Equivalence of Gyn GEC-ESTRO guidelines for image guided cervical brachytherapy with EUD-based dose prescription

    International Nuclear Information System (INIS)

    Shaw, William; Rae, William ID; Alber, Markus L

    2013-01-01

    To establish a generalized equivalent uniform dose (gEUD) -based prescription method for Image Guided Brachytherapy (IGBT) that reproduces the Gyn GEC-ESTRO WG (GGE) prescription for cervix carcinoma patients on CT images with limited soft tissue resolution. The equivalence of two IGBT planning approaches was investigated in 20 patients who received external beam radiotherapy (EBT) and 5 concomitant high dose rate IGBT treatments. The GGE planning strategy based on dose to the most exposed 2 cm 3 (D2cc) was used to derive criteria for the gEUD-based planning of the bladder and rectum. The safety of gEUD constraints in terms of GGE criteria was tested by maximizing dose to the gEUD constraints for individual fractions. The gEUD constraints of 3.55 Gy for the rectum and 5.19 Gy for the bladder were derived. Rectum and bladder gEUD-maximized plans resulted in D2cc averages very similar to the initial GGE criteria. Average D2ccs and EUDs from the full treatment course were comparable for the two techniques within both sets of normal tissue constraints. The same was found for the tumor doses. The derived gEUD criteria for normal organs result in GGE-equivalent IGBT treatment plans. The gEUD-based planning considers the entire dose distribution of organs in contrast to a single dose-volume-histogram point

  10. Study of absorbed dose distribution to high energy electron beams

    International Nuclear Information System (INIS)

    Cecatti, E.R.

    1983-01-01

    The depth absorbed dose distribution by electron beams was studied. The influence of the beam energy, the energy spread, field size and design characteristics of the accelerator was relieved. Three accelerators with different scattering and collimation systems were studied leading todifferent depth dose distributions. A theoretical model was constructed in order to explain the increase in the depth dose in the build-up region with the increase of the energy. The model utilizes a three-dimensional formalism based on the Fermi-Eyges multiple scattering theory, with the introduction of modifications that takes into account the criation of secondary electrons. (Author) [pt

  11. The interaction of platinum complexes with low doses of X-rays in hypoxic cells

    International Nuclear Information System (INIS)

    Skov, K.A.

    1992-01-01

    It is not clear why electron affinic compounds (O2, nitroimidazoles) should be more effective sensitizers at high doses (modify double events, 6, 16) while platinum complexes interact to a greater extent at low doses (modification of single-events). The possibility that crosslinks are involved requires further consideration. While DNA intrastrand crosslinks do not appear essential, future low dose experiments are planned to determine the role of interstrand and DNA-protein crosslinks in modifying response at clinical doses. (author). 31 refs., 2 tabs

  12. Vacua of maximal gauged D=3 supergravities

    International Nuclear Information System (INIS)

    Fischbacher, T; Nicolai, H; Samtleben, H

    2002-01-01

    We analyse the scalar potentials of maximal gauged three-dimensional supergravities which reveal a surprisingly rich structure. In contrast to maximal supergravities in dimensions D≥4, all these theories possess a maximally supersymmetric (N=16) ground state with negative cosmological constant Λ 2 gauged theory, whose maximally supersymmetric groundstate has Λ = 0. We compute the mass spectra of bosonic and fermionic fluctuations around these vacua and identify the unitary irreducible representations of the relevant background (super)isometry groups to which they belong. In addition, we find several stationary points which are not maximally supersymmetric, and determine their complete mass spectra as well. In particular, we show that there are analogues of all stationary points found in higher dimensions, among them are de Sitter (dS) vacua in the theories with noncompact gauge groups SO(5, 3) 2 and SO(4, 4) 2 , as well as anti-de Sitter (AdS) vacua in the compact gauged theory preserving 1/4 and 1/8 of the supersymmetries. All the dS vacua have tachyonic instabilities, whereas there do exist nonsupersymmetric AdS vacua which are stable, again in contrast to the D≥4 theories

  13. Modifications of the thorax radiography after postoperative irradiation in mammary carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Scheier, M; Rhomberg, W; Schelling, F

    1987-02-01

    The radiogenic modifications of the thorax radiography were evaluated in 100 patients irradiated postoperatively for mammary carcinoma between January, 1980 and March, 1983. No adjuvant chemotherapy was given. A telecobalt unit was used for the irradiations. A computer-assisted planning (Evados) was applied in order to obtain an individual optimization especially for the fields situated at the thoracic walls. The average focal doses to the thoracic wall and the regional lymph nodes were between 50 and 52 Gy. Taking into consideration all modifications visualized by radiography, 65% of patients had subacute radiogenic reactions in the lungs, especially in the apex fields. In general the modifications had no clinical importance. Only seven patients presented more severe forms of pneumonitis with clinical symptoms. Fibroses were developed only in the apex fields; infraclavicular infiltrations were seen only in exceptional cases. There were no costal necroses, essential pleural reactions, or radiogenic enlargements of the heart shadow. The rate of pulmonary reactions with clinical symptoms is reduced as compared with former techniques, e.g. opposing tangential fields. The knowledge of anamnesis and typical radiographic modifications should help to avoid problems of differentiation between apex reactions and tuberculosis.

  14. Accelerated postirradiation recovery of hematopoietic marrow following priming with low doses of vincristine

    International Nuclear Information System (INIS)

    Johnke, R.M.; Abernathy, R.S.

    1990-01-01

    The present investigation is a continuation of efforts to characterize the radioprotective potential of priming with vincristine (VcR). In this study, the postirradiation recovery kinetics of the marrow's hematopoietic stem cell, progenitor cell, and stromal cell compartments were monitored following exposure to a range of sublethal radiation doses to determine (a) the optimal VcR/radiation intertreatment interval for achieving maximal hematopoietic protection, (b) whether this optimal interval is influenced by the dose of radiation administered, and (c) whether the radioprotection observed involves the hematopoietic stroma. The results demonstrate that the degree of radioprotection observed was significantly influenced by the scheduling of the VcR priming dose with respect to the radiation exposure. An intertreatment interval of 24 h provided maximal radioprotective benefit irrespective of the radiation dose administered. Additionally, the radioprotection following VcR priming appeared to be more the result of an accelerated recovery in the hematopoietic stem cell and progenitor cell compartments than a change in their intrinsic radiosensitivity. The data also suggest that this accelerated recovery was not a consequence of greater radioprotection of marrow stroma. Finally, the radioprotection observed following VcR priming did not appear to involve a selective lineage response by either the erythroid or the granulomonocytic progenitor compartments

  15. Radiation-induced-radioresistance: mechanisms and modification radioprotection

    International Nuclear Information System (INIS)

    Bala, Madhu

    2005-01-01

    Full text: The term radiation-induced-radioresistance (RIR) has been chosen to explain a particular class of resistance against lethal doses of radiation, which is transient and is induced by pre-exposure to low doses of radiation. This is a genetically governed phenomenon and is different from adaptation which in one of its several senses, refers to evolutionary transformation into new behavioural patterns. RIR is understood to be an evolutionarily conserved fundamental cellular defense mechanism. Small doses of radiation acting as stress stimuli evoke a concerted action of molecular pathways which help the organism to cope-up with the genotoxic effects of lethal doses of radiation given subsequently. Such molecular pathways are a complex interplay of genetic and biochemical entities and are increasingly becoming the focus of research world over. Most of our information on this subject has been gathered from prokaryotes, simpler eukaryotes, human cells and the epidemiological studies. A number of genes such as GADD 45, CDKN1A, PBP74, DIR1, DDR have been reported by to participate in RIR. However, till date, the mechanism of RIR remain poorly understood. In this deliberation some of our findings on mechanisms of RIR will be presented. Further, modification of RIR by a metabolic modifier, presently under clinical investigations for tumor radiotherapy, will also be presented

  16. Modification of radiation effect by sodium fluoride in Tradescantia

    International Nuclear Information System (INIS)

    Cebulska-Wasilewska, A.; Guminska, M.; Huczkowski, J.; Kuternozinska, W.

    1988-01-01

    Frequency of somatic mutations in the Tradescantia stamen hairs served as a measure of biological effect of gamma irradiation with single and split doses and of modifications caused by sodium fluoride. It was found that treatment of plants with fluoride before irradiation affects considerably radiation-induced mutations. The changed peak mutation frequency in plants treated with fluoride suggests that it vitally influences the repair processes of DNA and possibly modifies the mutation spectrum. 14 refs., 3 figs. (author)

  17. Clinical and symptomatological study of pigs subjected to a lethal dose of integral gamma irradiation; Etude clinique et symptomatologique chez le porc soumis a une irradiation gamma totale a dose letale

    Energy Technology Data Exchange (ETDEWEB)

    Vaiman, M; Guenet, J -L; Maas, J; Nizza, P

    1966-05-01

    Results are reported from a clinical and haematological study on a Corsican species of pigs wholly exposed to an approximately lethal dose of {gamma} radiation. The aim of this work was to examine the changes in the irradiation syndrome of irradiation for pigs to make it thus possible to devise further experiments, in particular in the therapeutic field. The dose received was 285 rads (measured as the absorption in the vertical antero-posterior medial plane). Data are presented on cyto-haematological changes in the blood circulating immediately after irradiation, and followed up to death, and changes in the medullary cytology after irradiation. The clinical picture of lethal radiation injury in swine is described. (authors) [French] Les auteurs rapportent les resultats d'une etude clinique et hematologique chez des porcs de race corse irradies in toto a dose sensiblement letale. Le but de cette etude etait de connaitre l'evolution du syndrome aigu d'irradiation chez le porc et de permettre ainsi le developpement d'experimentations ulterieures, en particulier dans le domaine therapeutique. La dose delivree etait de 285 rad (en dose absorbee au niveau du plan median vertical anteroposterieur. L'etude a porte essentiellement: 1. Sur les modifications cyclo-hematologiques du sang circulant immediatement apres l'irradiation, pour les differentes lignees cellulaires; l'evolution de ces modifications a ete notee jusqu'a la mort; 2. Sur les modifications de la cytologie medullaire apres irradiation (evolution du myelogramme et essai d'evaluation de la cellularite de la moelle osseuse);: 3. Sur les signes cliniques, d'ailleurs tres discrets, observes chez les porcs apres irradiation. (auteurs)

  18. Clinical and symptomatological study of pigs subjected to a lethal dose of integral gamma irradiation; Etude clinique et symptomatologique chez le porc soumis a une irradiation gamma totale a dose letale

    Energy Technology Data Exchange (ETDEWEB)

    Vaiman, M.; Guenet, J.-L.; Maas, J.; Nizza, P

    1966-05-01

    Results are reported from a clinical and haematological study on a Corsican species of pigs wholly exposed to an approximately lethal dose of {gamma} radiation. The aim of this work was to examine the changes in the irradiation syndrome of irradiation for pigs to make it thus possible to devise further experiments, in particular in the therapeutic field. The dose received was 285 rads (measured as the absorption in the vertical antero-posterior medial plane). Data are presented on cyto-haematological changes in the blood circulating immediately after irradiation, and followed up to death, and changes in the medullary cytology after irradiation. The clinical picture of lethal radiation injury in swine is described. (authors) [French] Les auteurs rapportent les resultats d'une etude clinique et hematologique chez des porcs de race corse irradies in toto a dose sensiblement letale. Le but de cette etude etait de connaitre l'evolution du syndrome aigu d'irradiation chez le porc et de permettre ainsi le developpement d'experimentations ulterieures, en particulier dans le domaine therapeutique. La dose delivree etait de 285 rad (en dose absorbee au niveau du plan median vertical anteroposterieur. L'etude a porte essentiellement: 1. Sur les modifications cyclo-hematologiques du sang circulant immediatement apres l'irradiation, pour les differentes lignees cellulaires; l'evolution de ces modifications a ete notee jusqu'a la mort; 2. Sur les modifications de la cytologie medullaire apres irradiation (evolution du myelogramme et essai d'evaluation de la cellularite de la moelle osseuse);: 3. Sur les signes cliniques, d'ailleurs tres discrets, observes chez les porcs apres irradiation. (auteurs)

  19. Chinese herbal dose in ancient and modern times: a comparative study.

    Science.gov (United States)

    He, Shimin

    2013-04-01

    Appropriate dose guarantees Chinese herb's safety and effectiveness. There are adult dose criteria for Chinese herbs in decoction in the Pharmacopoeia of the People's Republic of China (2010 Edition) at present. But Chinese herbs have been frequently used in much higher doses than the dose criteria. This study has been conducted to test the dependability of the dose criteria. Twenty Chinese herbs were selected as representatives and their adult doses in decoction in Bei Ji Qian Jin Yao Fang, a famous ancient literature, have been reviewed and compared with those in the Pharmacopoeia of the People's Republic of China (2010 Edition). The adult dose criteria for all these 20 Chinese herbs in the Pharmacopoeia of the People's Republic of China (2010 Edition) haven't covered those in Bei Ji Qian Jin Yao Fang. Furthermore, maximal adult doses in the dose criteria are much lower than those in Bei Ji Qian Jin Yao Fang. The dose criteria in the Pharmacopoeia of the People's Republic of China (2010 Edition) are not comprehensive enough. Studying ancient literatures is an effective method to gain precious Chinese herbs' dose data and helps for new dose criteria's establishment in the future.

  20. Attentional bias modification based on visual probe task: methodological issues, results and clinical relevance

    Directory of Open Access Journals (Sweden)

    Fernanda Machado Lopes

    2015-12-01

    Full Text Available Introduction: Attentional bias, the tendency that a person has to drive or maintain attention to a specific class of stimuli, may play an important role in the etiology and persistence of mental disorders. Attentional bias modification has been studied as a form of additional treatment related to automatic processing. Objectives: This systematic literature review compared and discussed methods, evidence of success and potential clinical applications of studies about attentional bias modification (ABM using a visual probe task. Methods: The Web of Knowledge, PubMed and PsycInfo were searched using the keywords attentional bias modification, attentional bias manipulation and attentional bias training. We selected empirical studies about ABM training using a visual probe task written in English and published between 2002 and 2014. Results: Fifty-seven studies met inclusion criteria. Most (78% succeeded in training attention in the predicted direction, and in 71% results were generalized to other measures correlated with the symptoms. Conclusions: ABM has potential clinical utility, but to standardize methods and maximize applicability, future studies should include clinical samples and be based on findings of studies about its effectiveness.

  1. Sex differences in autonomic function following maximal exercise.

    Science.gov (United States)

    Kappus, Rebecca M; Ranadive, Sushant M; Yan, Huimin; Lane-Cordova, Abbi D; Cook, Marc D; Sun, Peng; Harvey, I Shevon; Wilund, Kenneth R; Woods, Jeffrey A; Fernhall, Bo

    2015-01-01

    Heart rate variability (HRV), blood pressure variability, (BPV) and heart rate recovery (HRR) are measures that provide insight regarding autonomic function. Maximal exercise can affect autonomic function, and it is unknown if there are sex differences in autonomic recovery following exercise. Therefore, the purpose of this study was to determine sex differences in several measures of autonomic function and the response following maximal exercise. Seventy-one (31 males and 40 females) healthy, nonsmoking, sedentary normotensive subjects between the ages of 18 and 35 underwent measurements of HRV and BPV at rest and following a maximal exercise bout. HRR was measured at minute one and two following maximal exercise. Males have significantly greater HRR following maximal exercise at both minute one and two; however, the significance between sexes was eliminated when controlling for VO2 peak. Males had significantly higher resting BPV-low-frequency (LF) values compared to females and did not significantly change following exercise, whereas females had significantly increased BPV-LF values following acute maximal exercise. Although males and females exhibited a significant decrease in both HRV-LF and HRV-high frequency (HF) with exercise, females had significantly higher HRV-HF values following exercise. Males had a significantly higher HRV-LF/HF ratio at rest; however, both males and females significantly increased their HRV-LF/HF ratio following exercise. Pre-menopausal females exhibit a cardioprotective autonomic profile compared to age-matched males due to lower resting sympathetic activity and faster vagal reactivation following maximal exercise. Acute maximal exercise is a sufficient autonomic stressor to demonstrate sex differences in the critical post-exercise recovery period.

  2. Eccentric exercise decreases maximal insulin action in humans

    DEFF Research Database (Denmark)

    Asp, Svend; Daugaard, J R; Kristiansen, S

    1996-01-01

    subjects participated in two euglycaemic clamps, performed in random order. One clamp was preceded 2 days earlier by one-legged eccentric exercise (post-eccentric exercise clamp (PEC)) and one was without the prior exercise (control clamp (CC)). 2. During PEC the maximal insulin-stimulated glucose uptake...... for all three clamp steps used (P maximal activity of glycogen synthase was identical in the two thighs for all clamp steps. 3. The glucose infusion rate (GIR......) necessary to maintain euglycaemia during maximal insulin stimulation was lower during PEC compared with CC (15.7%, 81.3 +/- 3.2 vs. 96.4 +/- 8.8 mumol kg-1 min-1, P maximal...

  3. A nutrient-driven tRNA modification alters translational fidelity and genome-wide protein coding across an animal genus.

    Science.gov (United States)

    Zaborske, John M; DuMont, Vanessa L Bauer; Wallace, Edward W J; Pan, Tao; Aquadro, Charles F; Drummond, D Allan

    2014-12-01

    Natural selection favors efficient expression of encoded proteins, but the causes, mechanisms, and fitness consequences of evolved coding changes remain an area of aggressive inquiry. We report a large-scale reversal in the relative translational accuracy of codons across 12 fly species in the Drosophila/Sophophora genus. Because the reversal involves pairs of codons that are read by the same genomically encoded tRNAs, we hypothesize, and show by direct measurement, that a tRNA anticodon modification from guanosine to queuosine has coevolved with these genomic changes. Queuosine modification is present in most organisms but its function remains unclear. Modification levels vary across developmental stages in D. melanogaster, and, consistent with a causal effect, genes maximally expressed at each stage display selection for codons that are most accurate given stage-specific queuosine modification levels. In a kinetic model, the known increased affinity of queuosine-modified tRNA for ribosomes increases the accuracy of cognate codons while reducing the accuracy of near-cognate codons. Levels of queuosine modification in D. melanogaster reflect bioavailability of the precursor queuine, which eukaryotes scavenge from the tRNAs of bacteria and absorb in the gut. These results reveal a strikingly direct mechanism by which recoding of entire genomes results from changes in utilization of a nutrient.

  4. A nutrient-driven tRNA modification alters translational fidelity and genome-wide protein coding across an animal genus.

    Directory of Open Access Journals (Sweden)

    John M Zaborske

    2014-12-01

    Full Text Available Natural selection favors efficient expression of encoded proteins, but the causes, mechanisms, and fitness consequences of evolved coding changes remain an area of aggressive inquiry. We report a large-scale reversal in the relative translational accuracy of codons across 12 fly species in the Drosophila/Sophophora genus. Because the reversal involves pairs of codons that are read by the same genomically encoded tRNAs, we hypothesize, and show by direct measurement, that a tRNA anticodon modification from guanosine to queuosine has coevolved with these genomic changes. Queuosine modification is present in most organisms but its function remains unclear. Modification levels vary across developmental stages in D. melanogaster, and, consistent with a causal effect, genes maximally expressed at each stage display selection for codons that are most accurate given stage-specific queuosine modification levels. In a kinetic model, the known increased affinity of queuosine-modified tRNA for ribosomes increases the accuracy of cognate codons while reducing the accuracy of near-cognate codons. Levels of queuosine modification in D. melanogaster reflect bioavailability of the precursor queuine, which eukaryotes scavenge from the tRNAs of bacteria and absorb in the gut. These results reveal a strikingly direct mechanism by which recoding of entire genomes results from changes in utilization of a nutrient.

  5. Maximize x(a - x)

    Science.gov (United States)

    Lange, L. H.

    1974-01-01

    Five different methods for determining the maximizing condition for x(a - x) are presented. Included is the ancient Greek version and a method attributed to Fermat. None of the proofs use calculus. (LS)

  6. Oxidative DNA base modifications as factors in carcinogenesis

    International Nuclear Information System (INIS)

    Olinski, R.; Jaruga, P.; Zastawny, T.H.

    1998-01-01

    Reactive oxygen species can cause extensive DNA modifications including modified bases. Some of the DNA base damage has been found to possess premutagenic properties. Therefore, if not repaired, it can contribute to carcinogenesis. We have found elevated amounts of modified bases in cancerous and precancerous tissues as compared with normal tissues. Most of the agents used in anticancer therapy are paradoxically responsible for induction of secondary malignancies and some of them may generate free radicals. The results of our experiments provide evidence that exposure of cancer patients to therapeutic doses of ionizing radiation and anticancer drugs cause base modifications in genomic DNA of lymphocytes. Some of these base damages could lead to mutagenesis in critical genes and ultimately to secondary cancers such as leukemias. This may point to an important role of oxidative base damage in cancer initiation. Alternatively, the increased level of the modified base products may contribute to genetic instability and metastatic potential of tumor cells. (author)

  7. Implications of the quadratic cell survival curve and human skin radiation ''tolerance doses'' on fractionation and superfractionation dose selection

    International Nuclear Information System (INIS)

    Douglas, B.G.

    1982-01-01

    An analysis of early published multifraction orthovoltage human acute skin irradiation tolerance isoeffect doses is presented. It indicates that human acute skin radiation reactions may result from the repetition, with each dose fraction, of a cell survival curve of the form: S = e/sup -(αD + βD 2 )/). The analysis also shows no need for an independent proliferation related time factor for skin, for daily treatments of six weeks or less in duration. The value obtained for the constant β/α for orthovoltage irradiation from these data is 2.9 x 10 -3 rad -1 for the cell line determining acute skin tolerance. A radiation isoeffect relationship, based on the quadratic cell survival curve, is introduced for human skin. This relationship has some advantages over the nominal standard dose (NSD). First, its use is not restricted to tolerance level reactions. Second, a modification of the relationship, which is also introduced, may be employed in the selection of doses per treatment when irradiation dose fractions are administered at short intervals where repair of sublethal injury is incomplete

  8. Low-Dose Ionizing Radiation Exposure, Oxidative Stress and Epigenetic Programing of Health and Disease.

    Science.gov (United States)

    Tharmalingam, Sujeenthar; Sreetharan, Shayenthiran; Kulesza, Adomas V; Boreham, Douglas R; Tai, T C

    2017-10-01

    Ionizing radiation exposure from medical diagnostic imaging has greatly increased over the last few decades. Approximately 80% of patients who undergo medical imaging are exposed to low-dose ionizing radiation (LDIR). Although there is widespread consensus regarding the harmful effects of high doses of radiation, the biological effects of low-linear energy transfer (LET) LDIR is not well understood. LDIR is known to promote oxidative stress, however, these levels may not be large enough to result in genomic mutations. There is emerging evidence that oxidative stress causes heritable modifications via epigenetic mechanisms (DNA methylation, histone modification, noncoding RNA regulation). These epigenetic modifications result in permanent cellular transformations without altering the underlying DNA nucleotide sequence. This review summarizes the major concepts in the field of epigenetics with a focus on the effects of low-LET LDIR (stress on epigenetic gene modification. In this review, we show evidence that suggests that LDIR-induced oxidative stress provides a mechanistic link between LDIR and epigenetic gene regulation. We also discuss the potential implication of LDIR exposure during pregnancy where intrauterine fetal development is highly susceptible to oxidative stress-induced epigenetic programing.

  9. Proceedings of an international workshop on historic dose experience and dose reduction (ALARA) at nuclear power plants

    International Nuclear Information System (INIS)

    Horan, J.R.; Baum, J.W.; Dionne, B.J.

    1985-06-01

    Dose reduction data and experience from 28 foreign and 10 US nuclear power plants was examined to determine causes for the wide variations in occupational dose from country to country. Major topics discussed were: steam generator and refueling maintenance problems; utility and supplier ALARA programs; effectiveness of dose-reduction modifications; attitudes and training; current and future dose-reduction research. While many parameters contribute to differences of occupational doses between plants from different nations, it is clear that most US plants have higher collective dose equivalent per reactor per megawatt-year than most other countries, even for plants of similar size and age. Worldwide, Finnish and Swedish plants, both PWR and BWR, have achieved the lowest values. Major factors which contribute to low doses include: (1) minimization of cobalt in primary system components exposed to water; (2) careful plant design, layout and component segregation and shielding; (3) plant standardization; (4) selection of components and systems for increased reliability; (5) management interest and commitment; (6) minimum number of workers and in-depth worker training; (7) careful control of primary system oxygen and pH; (8) good primary system water purity to minimize corrosion product formation; (9) use of special tools and robotics; (10) decontamination and passivation of primary systems and components; and (11) extent of backfitting and mandated inspections

  10. Radiation dose to neonates on a Special Care Baby Unit

    International Nuclear Information System (INIS)

    Faulkner, K.; Barry, J.L.; Smalley, P.

    1989-01-01

    The skin entrance dose to neonates on a special care baby unit was estimated from a knowledge of the technique factors, X-ray tube output and backscatter factors. Normalized organ dose data were employed to estimate radiation dose to a number of critical organs. Methods of reducing radiation dose to neonates were investigated. Initially, this involved changing the radiographic technique factors and introducing a lead rubber adjustable collimator, placed on top of the incubator, in addition to light beam diaphragms on the X-ray tube. These modifications to the examination technique appeared to reduce average entrance dose per radiograph from 92 μGy, to 58 μGy, a reduction of 37%. Later, a rare-earth film-screen combination was introduced to replace existing fast calcium tungstate screens. This enabled average entrance dose per radiograph to be reduced to 39 μGy, a further reduction of 33%. The mean radiation dose to a neonate is mainly determined by the number of radiographs. (author)

  11. Radiation dose to neonates on a Special Care Baby Unit

    Energy Technology Data Exchange (ETDEWEB)

    Faulkner, K.; Barry, J.L.; Smalley, P.

    1989-03-01

    The skin entrance dose to neonates on a special care baby unit was estimated from a knowledge of the technique factors, X-ray tube output and backscatter factors. Normalized organ dose data were employed to estimate radiation dose to a number of critical organs. Methods of reducing radiation dose to neonates were investigated. Initially, this involved changing the radiographic technique factors and introducing a lead rubber adjustable collimator, placed on top of the incubator, in addition to light beam diaphragms on the X-ray tube. These modifications to the examination technique appeared to reduce average entrance dose per radiograph from 92 ..mu..Gy, to 58 ..mu..Gy, a reduction of 37%. Later, a rare-earth film-screen combination was introduced to replace existing fast calcium tungstate screens. This enabled average entrance dose per radiograph to be reduced to 39 ..mu..Gy, a further reduction of 33%. The mean radiation dose to a neonate is mainly determined by the number of radiographs.

  12. Evaluation of Gene Modification Strategies for the Development of Low-Alcohol-Wine Yeasts

    Science.gov (United States)

    Kutyna, D. R.; Solomon, M. R.; Black, C. A.; Borneman, A.; Henschke, P. A.; Pretorius, I. S.; Chambers, P. J.

    2012-01-01

    Saccharomyces cerevisiae has evolved a highly efficient strategy for energy generation which maximizes ATP energy production from sugar. This adaptation enables efficient energy generation under anaerobic conditions and limits competition from other microorganisms by producing toxic metabolites, such as ethanol and CO2. Yeast fermentative and flavor capacity forms the biotechnological basis of a wide range of alcohol-containing beverages. Largely as a result of consumer demand for improved flavor, the alcohol content of some beverages like wine has increased. However, a global trend has recently emerged toward lowering the ethanol content of alcoholic beverages. One option for decreasing ethanol concentration is to use yeast strains able to divert some carbon away from ethanol production. In the case of wine, we have generated and evaluated a large number of gene modifications that were predicted, or known, to impact ethanol formation. Using the same yeast genetic background, 41 modifications were assessed. Enhancing glycerol production by increasing expression of the glyceraldehyde-3-phosphate dehydrogenase gene, GPD1, was the most efficient strategy to lower ethanol concentration. However, additional modifications were needed to avoid negatively affecting wine quality. Two strains carrying several stable, chromosomally integrated modifications showed significantly lower ethanol production in fermenting grape juice. Strain AWRI2531 was able to decrease ethanol concentrations from 15.6% (vol/vol) to 13.2% (vol/vol), whereas AWRI2532 lowered ethanol content from 15.6% (vol/vol) to 12% (vol/vol) in both Chardonnay and Cabernet Sauvignon juices. Both strains, however, produced high concentrations of acetaldehyde and acetoin, which negatively affect wine flavor. Further modifications of these strains allowed reduction of these metabolites. PMID:22729542

  13. The use of potassium dichromate for ultra high dose up to 120 kGy measurements in industrial irradiation process

    International Nuclear Information System (INIS)

    Conceicao, Cirilo C.S.

    2009-01-01

    The purpose of this work is the study of radiation-induced reduction of the Potassium Dichromate dosimeter in perchloric acid using modification in the composition of Dichromate dosimeter proposed by Sharpe (NPL, October 1982) to extend dose limit up to 120 kGy. This modification can allow measuring dose in process of irradiation of gem and cork directly, in these processes that the absorbed doses are very high. The dosimeter study reached linear response between 10 to 120 kGy. This dosimeter was traceable to the international metrology system, using Gammacell calibrated by Fricke reference dosimeter. The evaluation of the doses was done by spectrophotometric method. Compared to the costs using PMMA (perpex dosimeters), the use of dichromate dosimeters can reduce up to 70% of the dosimetry costs in Brazil. (author)

  14. Computational fluid dynamics (CFD) assisted performance evaluation of the Twincer (TM) disposable high-dose dry powder inhaler

    NARCIS (Netherlands)

    de Boer, Anne H.; Hagedoorn, Paul; Woolhouse, Robert; Wynn, Ed

    Objectives To use computational fluid dynamics (CFD) for evaluating and understanding the performance of the high-dose disposable Twincer (TM) dry powder inhaler, as well as to learn the effect of design modifications on dose entrainment, powder dispersion and retention behaviour. Methods Comparison

  15. Fruit-flies in low-dose exposure experiments

    International Nuclear Information System (INIS)

    Zajnullin, V.G.; Moskalev, A.A.; Shaposhnikov, M.V.; Sheptyakova, A.I.

    2002-01-01

    In vivo exposure of fruit-flies of Drosophila melanogaster line to low doses provided new data indicating that mechanisms of induced genetic instability are involved in radiation-induced alteration of genotype. It is true for increase of genetic variance due to change in transposition number, for change in adaptation capabilities due to modification of gene expression, and for mutability-associated reparation and apoptosis. (author)

  16. Utility Maximization in Nonconvex Wireless Systems

    CERN Document Server

    Brehmer, Johannes

    2012-01-01

    This monograph formulates a framework for modeling and solving utility maximization problems in nonconvex wireless systems. First, a model for utility optimization in wireless systems is defined. The model is general enough to encompass a wide array of system configurations and performance objectives. Based on the general model, a set of methods for solving utility maximization problems is developed. The development is based on a careful examination of the properties that are required for the application of each method. The focus is on problems whose initial formulation does not allow for a solution by standard convex methods. Solution approaches that take into account the nonconvexities inherent to wireless systems are discussed in detail. The monograph concludes with two case studies that demonstrate the application of the proposed framework to utility maximization in multi-antenna broadcast channels.

  17. Monte Carlo dose calculations for BNCT treatment of diffuse human lung tumours

    International Nuclear Information System (INIS)

    Altieri, S.; Bortolussi, S.; Bruschi, P.

    2006-01-01

    In order to test the possibility to apply BNCT in the core of diffuse lung tumours, dose distribution calculations were made. The simulations were performed with the Monte Carlo code MCNP.4c2, using the male computational phantom Adam, version 07/94. Volumes of interest were voxelized for the tally requests, and results were obtained for tissues with and without Boron. Different collimated neutron sources were tested in order to establish the proper energies, as well as single and multiple beams to maximize neutron flux uniformity inside the target organs. Flux and dose distributions are reported. The use of two opposite epithermal neutron collimated beams insures good levels of dose homogeneity inside the lungs, with a substantially lower radiation dose delivered to surrounding structures. (author)

  18. Addressing the common pathway underlying hypertension and diabetes in people who are obese by maximizing health: the ultimate knowledge translation gap.

    Science.gov (United States)

    Dean, Elizabeth; Lomi, Constantina; Bruno, Selma; Awad, Hamzeh; O'Donoghue, Grainne

    2011-03-06

    In accordance with the WHO definition of health, this article examines the alarming discord between the epidemiology of hypertension, type 2 diabetes mellitus (T2DM), and obesity and the low profile of noninvasive (nondrug) compared with invasive (drug) interventions with respect to their prevention, reversal and management. Herein lies the ultimate knowledge translation gap and challenge in 21st century health care. Although lifestyle modification has long appeared in guidelines for medically managing these conditions, this evidence-based strategy is seldom implemented as rigorously as drug prescription. Biomedicine focuses largely on reducing signs and symptoms; the effects of the problem rather than the problem. This article highlights the evidence-based rationale supporting prioritizing the underlying causes and contributing factors for hypertension and T2DM, and, in turn, obesity. We argue that a primary focus on maximizing health could eliminate all three conditions, at best, or, at worst, minimize their severity, complications, and medication needs. To enable such knowledge translation and maximizing health outcome, the health care community needs to practice as an integrated team, and address barriers to effecting maximal health in all patients. Addressing the ultimate knowledge translation gap, by aligning the health care paradigm to 21st century needs, would constitute a major advance.

  19. Addressing the Common Pathway Underlying Hypertension and Diabetes in People Who Are Obese by Maximizing Health: The Ultimate Knowledge Translation Gap

    Directory of Open Access Journals (Sweden)

    Elizabeth Dean

    2011-01-01

    Full Text Available In accordance with the WHO definition of health, this article examines the alarming discord between the epidemiology of hypertension, type 2 diabetes mellitus (T2DM, and obesity and the low profile of noninvasive (nondrug compared with invasive (drug interventions with respect to their prevention, reversal and management. Herein lies the ultimate knowledge translation gap and challenge in 21st century health care. Although lifestyle modification has long appeared in guidelines for medically managing these conditions, this evidence-based strategy is seldom implemented as rigorously as drug prescription. Biomedicine focuses largely on reducing signs and symptoms; the effects of the problem rather than the problem. This article highlights the evidence-based rationale supporting prioritizing the underlying causes and contributing factors for hypertension and T2DM, and, in turn, obesity. We argue that a primary focus on maximizing health could eliminate all three conditions, at best, or, at worst, minimize their severity, complications, and medication needs. To enable such knowledge translation and maximizing health outcome, the health care community needs to practice as an integrated team, and address barriers to effecting maximal health in all patients. Addressing the ultimate knowledge translation gap, by aligning the health care paradigm to 21st century needs, would constitute a major advance.

  20. High dose gamma-ray standard

    International Nuclear Information System (INIS)

    Macrin, R.; Moraru, R.

    1999-01-01

    The high gamma-ray doses produced in a gamma irradiator are used, mainly, for radiation processing, i.e. sterilization of medical products, processing of food, modifications of polymers, irradiation of electronic devices, a.s.o. The used absorbed doses depend on the application and cover the range 10 Gy to 100 MGy. The regulations in our country require that the response of the dosimetry systems, used for the irradiation of food and medical products, be calibrated and traceable to the national standards. In order to be sure that the products receive the desired absorbed dose, appropriate dosimetric measurements must be performed, including the calibration of the dosemeters and their traceability to the national standards. The high dose gamma-ray measurements are predominantly based on the use of reference radiochemical dosemeters. Among them the ferrous sulfate can be used as reference dosemeter for low doses (up to 400 Gy) but due to its characteristics it deserves to be considered a standard dosemeter and to be used for transferring the conventional absorbed dose to other chemical dosemeters used for absorbed doses up to 100 MGy. The study of the ferrous sulfate dosemeter consisted in preparing many batches of solution by different operators in quality assurance conditions and in determining for all batches the linearity, the relative intrinsic error, the repeatability and the reproducibility. The principal results are the following: the linear regression coefficient: 0.999, the relative intrinsic error: max.6 %, the repeatability (for P* = 95 %): max.3 %, the reproducibility (P* = 95%): max.5 %. (authors)

  1. Mutation induction in haploid yeast after split-dose radiation-exposure. Pt. 1

    International Nuclear Information System (INIS)

    Schenk, K.; Zoelzer, F.; Kiefer, J.

    1989-01-01

    Mutation induction was investigated in wild-type haploid yeast Saccharomyces cerevisiae after split-dose UV-irradiation. Cells were exposed to fractionated 254 nm-UV-doses separated by intervals from 0 to 6 h with incubation either on non-nutrient or nutrient agar between. The test parameter was resistance to canavanine. If modifications of sensitivity due to incubation are appropriately taken into account there is no change of mutation frequency. (orig.)

  2. Brachytherapy at the Institut Gustave-Roussy: Personalized vaginal mould applicator: technical modification and improvement

    International Nuclear Information System (INIS)

    Albano, M.; Dumas, I.; Haie-Meder, C.

    2008-01-01

    Brachytherapy plays an important role in the treatment of patients with gynaecological cancers. At the Institut Gustave-Roussy, the technique of vaginal mould applicator has been used for decades. This technique allows a personalized tailored irradiation, integrating tumour shape, size and extension and vaginal anatomy. Vaginal expansion reduces the dose to the vaginal mucosa and to the organs at risk. We report a modification of the material used for vaginal mould manufacture. The advantages of the new material are a lighter weight, and transparency allowing a better accuracy in the placement of catheters for radioactive sources. This material is applicable for low dose-rate, pulse dose-rate and high dose-rate brachytherapy. Since 2001, more than 700 vaginal moulds have been manufactured with this new approach without any intolerance. (authors)

  3. Surface modification of RuO2 electrodes by laser irradiation and ion ...

    Indian Academy of Sciences (India)

    RuO2 thin layers were deposited on Ti supports by thermal decomposition of RuCl3 at 400°C. Some of the samples were subjected to laser irradiation between 0.5 and 1.5 J cm-2. Some others to Kr bombardment with doses between 1015 and 1016 cm-2. Modifications introduced by the surface treatments were monitored ...

  4. Cancer radiotherapy based on femtosecond IR laser-beam filamentation yielding ultra-high dose rates and zero entrance dose.

    Science.gov (United States)

    Meesat, Ridthee; Belmouaddine, Hakim; Allard, Jean-François; Tanguay-Renaud, Catherine; Lemay, Rosalie; Brastaviceanu, Tiberius; Tremblay, Luc; Paquette, Benoit; Wagner, J Richard; Jay-Gerin, Jean-Paul; Lepage, Martin; Huels, Michael A; Houde, Daniel

    2012-09-18

    Since the invention of cancer radiotherapy, its primary goal has been to maximize lethal radiation doses to the tumor volume while keeping the dose to surrounding healthy tissues at zero. Sadly, conventional radiation sources (γ or X rays, electrons) used for decades, including multiple or modulated beams, inevitably deposit the majority of their dose in front or behind the tumor, thus damaging healthy tissue and causing secondary cancers years after treatment. Even the most recent pioneering advances in costly proton or carbon ion therapies can not completely avoid dose buildup in front of the tumor volume. Here we show that this ultimate goal of radiotherapy is yet within our reach: Using intense ultra-short infrared laser pulses we can now deposit a very large energy dose at unprecedented microscopic dose rates (up to 10(11) Gy/s) deep inside an adjustable, well-controlled macroscopic volume, without any dose deposit in front or behind the target volume. Our infrared laser pulses produce high density avalanches of low energy electrons via laser filamentation, a phenomenon that results in a spatial energy density and temporal dose rate that both exceed by orders of magnitude any values previously reported even for the most intense clinical radiotherapy systems. Moreover, we show that (i) the type of final damage and its mechanisms in aqueous media, at the molecular and biomolecular level, is comparable to that of conventional ionizing radiation, and (ii) at the tumor tissue level in an animal cancer model, the laser irradiation method shows clear therapeutic benefits.

  5. Soft X-ray induced chemical modification of polysaccharides in vascular plant cell walls

    International Nuclear Information System (INIS)

    Cody, George D.; Brandes, Jay; Jacobsen, Chris; Wirick, Susan

    2009-01-01

    Scanning transmission X-ray microscopy and micro carbon X-ray Absorption Near Edge Spectroscopy (C-XANES) can provide quantitative information regarding the distribution of the biopolymers cellulose, hemicellulose, and lignin in vascular plant cell walls. In the case of angiosperms, flowering plants, C-XANES may also be able to distinguish variations in lignin monomer distributions throughout the cell wall. Polysaccharides are susceptible to soft X-ray irradiation induced chemical transformations that may complicate spectral analysis. The stability of a model polysaccharide, cellulose acetate, to variable doses of soft X-rays under conditions optimized for high quality C-XANES spectroscopy was investigated. The primary chemical effect of soft X-ray irradiation on cellulose acetate involves mass loss coincident with de-acetylation. A lesser amount of vinyl ketone formation also occurs. Reduction in irradiation dose via defocusing does enable high quality pristine spectra to be obtained. Radiation induced chemical modification studies of oak cell wall reveals that cellulose and hemicellulose are less labile to chemical modification than cellulose acetate. Strategies for obtaining pristine C-XANES spectra of polysaccharides are presented.

  6. Exact comparison of dose rate measurements and calculation of TN12/2 packages

    International Nuclear Information System (INIS)

    Taniuchi, H.; Matsuda, F.

    1998-01-01

    Both of dose rate measurements of TN 12/2 package and calculations by Monte Carlo code MORSE in SCALE code system and MCNP were performed to evaluate the difference between the measurement and the calculation and finding out the cause of the difference. The calculated gamma-ray dose rates agreed well with measured ones, but calculated neutron dose rates overestimated more than a factor of 1.7. When considering the cause of the difference and applying the modification into the neutron calculation, the calculated neutron dose rates become to agree well, and the factor decreased to around 1.3. (authors)

  7. Aging and loss decision making: increased risk aversion and decreased use of maximizing information, with correlated rationality and value maximization.

    Science.gov (United States)

    Kurnianingsih, Yoanna A; Sim, Sam K Y; Chee, Michael W L; Mullette-Gillman, O'Dhaniel A

    2015-01-01

    We investigated how adult aging specifically alters economic decision-making, focusing on examining alterations in uncertainty preferences (willingness to gamble) and choice strategies (what gamble information influences choices) within both the gains and losses domains. Within each domain, participants chose between certain monetary outcomes and gambles with uncertain outcomes. We examined preferences by quantifying how uncertainty modulates choice behavior as if altering the subjective valuation of gambles. We explored age-related preferences for two types of uncertainty, risk, and ambiguity. Additionally, we explored how aging may alter what information participants utilize to make their choices by comparing the relative utilization of maximizing and satisficing information types through a choice strategy metric. Maximizing information was the ratio of the expected value of the two options, while satisficing information was the probability of winning. We found age-related alterations of economic preferences within the losses domain, but no alterations within the gains domain. Older adults (OA; 61-80 years old) were significantly more uncertainty averse for both risky and ambiguous choices. OA also exhibited choice strategies with decreased use of maximizing information. Within OA, we found a significant correlation between risk preferences and choice strategy. This linkage between preferences and strategy appears to derive from a convergence to risk neutrality driven by greater use of the effortful maximizing strategy. As utility maximization and value maximization intersect at risk neutrality, this result suggests that OA are exhibiting a relationship between enhanced rationality and enhanced value maximization. While there was variability in economic decision-making measures within OA, these individual differences were unrelated to variability within examined measures of cognitive ability. Our results demonstrate that aging alters economic decision-making for

  8. Aging and loss decision making: increased risk aversion and decreased use of maximizing information, with correlated rationality and value maximization

    Directory of Open Access Journals (Sweden)

    Yoanna Arlina Kurnianingsih

    2015-05-01

    Full Text Available We investigated how adult aging specifically alters economic decision-making, focusing on examining alterations in uncertainty preferences (willingness to gamble and choice strategies (what gamble information influences choices within both the gains and losses domains. Within each domain, participants chose between certain monetary outcomes and gambles with uncertain outcomes. We examined preferences by quantifying how uncertainty modulates choice behavior as if altering the subjective valuation of gambles. We explored age-related preferences for two types of uncertainty, risk and ambiguity. Additionally, we explored how aging may alter what information participants utilize to make their choices by comparing the relative utilization of maximizing and satisficing information types through a choice strategy metric. Maximizing information was the ratio of the expected value of the two options, while satisficing information was the probability of winning.We found age-related alterations of economic preferences within the losses domain, but no alterations within the gains domain. Older adults (OA; 61 to 80 years old were significantly more uncertainty averse for both risky and ambiguous choices. OA also exhibited choice strategies with decreased use of maximizing information. Within OA, we found a significant correlation between risk preferences and choice strategy. This linkage between preferences and strategy appears to derive from a convergence to risk neutrality driven by greater use of the effortful maximizing strategy. As utility maximization and value maximization intersect at risk neutrality, this result suggests that OA are exhibiting a relationship between enhanced rationality and enhanced value maximization. While there was variability in economic decision-making measures within OA, these individual differences were unrelated to variability within examined measures of cognitive ability. Our results demonstrate that aging alters economic

  9. Gamma irradiation degradation/modification of 5-ethylidene 2-norbornene (ENB)-based ethylene propylene diene rubber (EPDM) depending on ENB content of EPDM and type/content of peroxides used in vulcanization

    Energy Technology Data Exchange (ETDEWEB)

    Ozdemir, Tonguc [Department of Polymer Science and Technology, Middle East Technical University, 06531 Ankara (Turkey)], E-mail: tonguc.ozdemir@tr.net

    2008-06-15

    In this study, the radiation degradation/modification of the vulcanized EPDM and the effects of dose rate, peroxide type/content in vulcanization system and ENB content of EPDM were studied to investigate the change in the extend of the modification/degradation of the mechanical properties of vulcanized EPDM via gamma irradiation. In addition, thermal, dynamic mechanical, ATR-FTIR, TGA, TGA-FTIR tests were carried out to understand the change of properties of vulcanized EPDM via irradiation. Samples were irradiated with two different dose rates of 1280 and 64.6 Gy/h. Total dose of irradiation was up to 184 kGy. The FTIR spectral analysis showed structural changes of EPDM via irradiation. It was observed that the dose rate changed the mechanical properties with different extends. The change of ENB content of EPDM and peroxide type and content in vulcanization system affect extend of the modification/degradation of the EPDM's properties.

  10. Modification of the radiological technique of Parma for reduction of irradiation dose

    Energy Technology Data Exchange (ETDEWEB)

    Stampfel, G.; Ionesco-Farco, F.

    1982-04-01

    A modified radiological technique to demonstrate the temporo-mandibular joint is presented. An ordinary X-ray tube put on the skin is directed 10/sup 0/ dorso-ventrally and 10/sup 0/ caudo-cranially to the temporo-mandibular joint. The irradiation skin dose applied is ten times smaller than by using the conventional contact technique.

  11. Maximally Informative Observables and Categorical Perception

    OpenAIRE

    Tsiang, Elaine

    2012-01-01

    We formulate the problem of perception in the framework of information theory, and prove that categorical perception is equivalent to the existence of an observable that has the maximum possible information on the target of perception. We call such an observable maximally informative. Regardless whether categorical perception is real, maximally informative observables can form the basis of a theory of perception. We conclude with the implications of such a theory for the problem of speech per...

  12. Effect of radiation-induced modification in fluoroelastomer

    International Nuclear Information System (INIS)

    Zen, Heloisa Augusto; Lugao, Ademar Benevolo

    2013-01-01

    Polymers exposed to ionizing irradiation, even at low doses, often undergo structural changes accompanied by molecular crosslinking and chain scission (degradation) reactions. The general effect of the radiation on polymers is determined by the ratio of crosslinking to chain scission events. This ratio depends on parameters such as chemical structure, physical state, radicals stability and mobility, irradiation rate and irradiation atmosphere. The radiation process is a large used technique to promote modification in their structures to apply them in different areas and is well known for its merits and potential in modifying the chemical and the physical properties of polymeric materials without cause drastic changes in their inherent properties, depend on the dose irradiated. In this study was used fluoroelastomer with 70% - fluor that having excellent thermal, chemical and mechanical properties. Vulcanized and non-vulcanized samples of this material were submitted to gamma radiation under air atmosphere in order to observe the effect of atmosphere in the polymer matrix. The irradiated doses were 5, 10 and 20kGy, at room temperature. The characterization was made by scanning electron microscope (SEM), infrared spectroscopy using attenuate reflectance (ATR-IR) and X-ray diffraction. The results demonstrated which was expected, the degradation reactions were observed. (author)

  13. Low doses of caffeine reduce heart rate during submaximal cycle ergometry

    Directory of Open Access Journals (Sweden)

    Wetter Thomas J

    2007-10-01

    Full Text Available Abstract Background The purpose of this study was to examine the cardiovascular effects of two low-levels of caffeine ingestion in non habitual caffeine users at various submaximal and maximal exercise intensities. Methods Nine male subjects (19–25 yr; 83.3 ± 3.1 kg; 184 ± 2 cm, underwent three testing sessions administered in a randomized and double-blind fashion. During each session, subjects were provided 4 oz of water and a gelatin capsule containing a placebo, 1.5 mg/kg caffeine, or 3.0 mg/kg caffeine. After thirty minutes of rest, a warm-up (30 Watts for 2 min the pedal rate of 60 rpm was maintained at a steady-state output of 60 watts for five minutes; increased to 120 watts for five minutes and to 180 watts for five minutes. After a 2 min rest the workload was 180 watts for one minute and increased by 30 watts every minute until exhaustion. Heart rate (HR was measured during the last 15-seconds of each minute of submaximal exercise. Systolic blood pressure (BP was measured at rest and during each of the three sub-maximal steady state power outputs. Minute ventilation (VE, Tidal volume (VT, Breathing frequency (Bf, Rating of perceived exertion (RPE, Respiratory exchange ratio (RER, and Oxygen consumption (VO2 were measured at rest and during each minute of exercise. Results Caffeine at 1.5 and 3.0 mg/kg body weight significantly lowered (p E, VT, VO2, RPE, maximal power output or time to exhaustion. Conclusion In non habitual caffeine users it appears that consuming a caffeine pill (1.5 & 3.0 mg/kg at a dose comparable to 1–3 cups of coffee lowers heart rate during submaximal exercise but not at near maximal and maximal exercise. In addition, this caffeine dose also only appears to affect systolic blood pressure at rest but not during cycling exercise.

  14. Cytogenetic adaptive response of cultured fish cells to low doses of X-rays

    International Nuclear Information System (INIS)

    Kurihara, Yasuyuki; Etoh, Hisami; Rienkjkarn, M.

    1992-01-01

    The adaptive response was examining chromosomal aberrations and micronucleus in cultured fish cells, ULF-23 (mudminnow) and CAF-31 (gold fish). When cultured fish cells were first irradiated with small doses of X-rays, they became less sensitive to subsequent exposures to high doses. The effective adaptive dose was 4.8 cGy-9.5 cGy. Adaptive doses given cells in the G1 phase were more effective than when given in the S phase. The adaptive response was maximal at 5 hours and disappeared at 10 hours after the adaptive dose. The expression of the response was inhibited by treatment with 3-aminobenzamide, as reported for mammalian cells, and with arabinofuranoside cytosine, an inhibitor of DNA polymerase alpha. Caffeine, an inhibitor of post-replicational repair, had no effect on the response. (author)

  15. Cytogenetic adaptive response of cultured fish cells to low doses of X-rays

    Energy Technology Data Exchange (ETDEWEB)

    Kurihara, Yasuyuki; Etoh, Hisami (National Inst. of Radiological Sciences, Chiba (Japan)); Rienkjkarn, M.

    1992-12-01

    The adaptive response was examining chromosomal aberrations and micronucleus in cultured fish cells, ULF-23 (mudminnow) and CAF-31 (gold fish). When cultured fish cells were first irradiated with small doses of X-rays, they became less sensitive to subsequent exposures to high doses. The effective adaptive dose was 4.8 cGy-9.5 cGy. Adaptive doses given cells in the G1 phase were more effective than when given in the S phase. The adaptive response was maximal at 5 hours and disappeared at 10 hours after the adaptive dose. The expression of the response was inhibited by treatment with 3-aminobenzamide, as reported for mammalian cells, and with arabinofuranoside cytosine, an inhibitor of DNA polymerase alpha. Caffeine, an inhibitor of post-replicational repair, had no effect on the response. (author).

  16. Maximally Entangled Multipartite States: A Brief Survey

    International Nuclear Information System (INIS)

    Enríquez, M; Wintrowicz, I; Życzkowski, K

    2016-01-01

    The problem of identifying maximally entangled quantum states of a composite quantum systems is analyzed. We review some states of multipartite systems distinguished with respect to certain measures of quantum entanglement. Numerical results obtained for 4-qubit pure states illustrate the fact that the notion of maximally entangled state depends on the measure used. (paper)

  17. Corporate Social Responsibility and Profit Maximizing Behaviour

    OpenAIRE

    Becchetti, Leonardo; Giallonardo, Luisa; Tessitore, Maria Elisabetta

    2005-01-01

    We examine the behavior of a profit maximizing monopolist in a horizontal differentiation model in which consumers differ in their degree of social responsibility (SR) and consumers SR is dynamically influenced by habit persistence. The model outlines parametric conditions under which (consumer driven) corporate social responsibility is an optimal choice compatible with profit maximizing behavior.

  18. Optimizing bevacizumab dosing in glioblastoma: less is more.

    Science.gov (United States)

    Ajlan, Abdulrazag; Thomas, Piia; Albakr, Abdulrahman; Nagpal, Seema; Recht, Lawrence

    2017-10-01

    Compared to traditional chemotherapies, where dose limiting toxicities represent the maximum possible dose, monoclonal antibody therapies are used at doses well below maximum tolerated dose. However, there has been little effort to ascertain whether there is a submaximal dose at which the efficacy/complication ratio is maximized. Thus, despite the general practice of using Bevacizumab (BEV) at dosages of 10 mg/kg every other week for glioma patients, there has not been much prior work examining whether the relatively high complication rates reported with this agent can be decreased by lowering the dose without impairing efficacy. We assessed charts from 80 patients who received BEV for glioblastoma to survey the incidence of complications relative to BEV dose. All patients were treated with standard upfront chemoradiation. The toxicity was graded based on the NCI CTCAE, version 4.03. The rate of BEV serious related adverse events was 12.5% (n = 10/80). There were no serious adverse events (≥grade 3) when the administered dose was (<3 mg/kg/week), compared to a 21% incidence in those who received higher doses (≥3 mg/kg/week) (P < 0.01). Importantly, the three patient deaths attributable to BEV administration occurred in patients receiving higher doses. Patients who received lower doses also had a better survival rate, although this did not reach statistical significance [median OS 39 for low dose group vs. 17.3 for high dose group (P = 0.07)]. Lower rates of serious BEV related toxicities are noted when lower dosages are used without diminishing positive clinical impact. Further work aimed at optimizing BEV dosage is justified.

  19. Modification of SKYSHINE-III to include cask array shadowing

    Energy Technology Data Exchange (ETDEWEB)

    Hertel, N.E. [Georgia Institute of Technology, Atlanta, GA (United States); Pfeifer, H.J. [NAC International, Norcross, GA (United States); Napolitano, D.G. [NISYS Corporation, Duluth, GA (United States)

    2000-03-01

    The NAC International version of SKYSHINE-III has been expanded to represent the radiation emissions from ISFSI (Interim Spent Fuel Storage Installations) dry storage casks using surface source descriptions. In addition, this modification includes a shadow shielding algorithm of the casks in the array. The resultant code is a flexible design tool which can be used to rapidly assess the impact of various cask loadings and arrangements. An example of its use in calculating dose rates for a 10x8 cask array is presented. (author)

  20. TLD array for precise dose measurements in stereotactic radiation techniques

    International Nuclear Information System (INIS)

    Ertl, A.; Kitz, K.; Griffitt, W.; Hartl, R.F.E.; Zehetmayer, M.

    1996-01-01

    We developed a new TLD array for precise dose measurement and verification of the spatial dose distribution in small radiation targets. It consists of a hemicylindrical, tissue-equivalent rod made of polystyrene with 17 parallel moulds for an exact positioning of each TLD. The spatial resolution of the TLD array was evaluated using the Leskell spherical phantom. Dose planning was performed with KULA 4.4 under stereotactic conditions on axial CT images. In the Leksell gamma unit the TLD array was irradiated with a maximal dose of 10 Gy with an unplugged 14 mm collimator. The doses delivered to the TLDs were rechecked by diode detector and film dosimetry and compared to the computer-generated dose profile. We found excellent agreement of our measured values, even at the critical penumbra decline. For the 14 mm and 18 mm collimator and for the 11 mm collimator combination we compared the measured and calculated data at full width at half maximum. This TLD array may be useful for phantom or tissue model studies on the spatial dose distribution in confined radiation targets as used in stereotactic radiotherapy. (author)

  1. Dose-escalated total body irradiation and autologous stem cell transplantation for refractory hematologic malignancy

    International Nuclear Information System (INIS)

    McAfee, Steven L.; Powell, Simon N.; Colby, Christine; Spitzer, Thomas R.

    2002-01-01

    Purpose: To evaluate the feasibility of dose escalation of total body irradiation (TBI) above the previously reported maximally tolerated dose, we have undertaken a Phase I-II trial of dose-escalated TBI with autologous peripheral blood stem cell transplantation (PBSCT) for chemotherapy-refractory lymphoma. Methods and Materials: Nine lymphoma patients with primary refractory disease (PRD) or in resistant relapse (RR) received dose-escalated TBI and PBSCT. The three dose levels of fractionated TBI (200 cGy twice daily) were 1,600 cGy, 1,800 cGy, and 2,000 cGy. Lung blocks were used to reduce the TBI transmission dose by 50%, and the chest wall dose was supplemented to the prescribed dose using electrons. Shielding of the kidneys was performed to keep the maximal renal dose at 1,600 cGy. Three patients, two with non-Hodgkin's lymphoma (NHL) in RR and one with PRD Hodgkin's disease, received 1,600 cGy + PBSCT, three patients (two NHL in RR, one PRD) received 1,800 cGy + PBSCT, and three patients with NHL (two in RR, one PRD) received 2,000 cGy + PBSCT. Results: Toxicities associated with this high-dose TBI regimen included reversible hepatic veno-occlusive disease in 1 patient, Grade 2 mucositis requiring narcotic analgesics in 8 patients, and neurologic toxicities consisting of a symmetrical sensory neuropathy (n=4) and Lhermitte's syndrome (n=1). Interstitial pneumonitis developed in 1 patient who received 1,800 cGy after receiving recombinant α-interferon (with exacerbation after rechallenge with interferon). Six (66%) patients achieved a response. Four (44%) patients achieved complete responses, three of which were of a duration greater than 1 year, and 2 (22%) patients achieved a partial response. One patient remains disease-free more than 5 years posttransplant. Corticosteroid-induced gastritis and postoperative infection resulted in the death of 1 patient in complete response, 429 days posttransplant. Conclusion: TBI in a dose range 1,600-2,000 cGy as

  2. Guinea pig maximization test

    DEFF Research Database (Denmark)

    Andersen, Klaus Ejner

    1985-01-01

    Guinea pig maximization tests (GPMT) with chlorocresol were performed to ascertain whether the sensitization rate was affected by minor changes in the Freund's complete adjuvant (FCA) emulsion used. Three types of emulsion were evaluated: the oil phase was mixed with propylene glycol, saline...

  3. Modification of the biologic dose to normal tissue by daily fraction

    Energy Technology Data Exchange (ETDEWEB)

    Wollin, M; Kagan, A R [Southern California Permanente Medical Group, Los Angeles Calif. (USA). Dep. of Radiation Therapy

    1976-12-01

    A method to predict normal tissue injury is proposed that includes high daily doses and unusual times successfully by calculating a new value called BIR (Biologic Index of Reaction). BIR and NSD were calculated for various normal tissue reactions. With the aid of statistical correlation techniques it is found that the BIR model is better than the NSD model in predicting radiation myelopathy and vocal edema and as good as NSD IN PREDICTING RIB FRACTURE/ Neither model predicts pericardial effusion. In no case were the results of BIR inferior to those of NSD.

  4. Gradient Dynamics and Entropy Production Maximization

    Science.gov (United States)

    Janečka, Adam; Pavelka, Michal

    2018-01-01

    We compare two methods for modeling dissipative processes, namely gradient dynamics and entropy production maximization. Both methods require similar physical inputs-how energy (or entropy) is stored and how it is dissipated. Gradient dynamics describes irreversible evolution by means of dissipation potential and entropy, it automatically satisfies Onsager reciprocal relations as well as their nonlinear generalization (Maxwell-Onsager relations), and it has statistical interpretation. Entropy production maximization is based on knowledge of free energy (or another thermodynamic potential) and entropy production. It also leads to the linear Onsager reciprocal relations and it has proven successful in thermodynamics of complex materials. Both methods are thermodynamically sound as they ensure approach to equilibrium, and we compare them and discuss their advantages and shortcomings. In particular, conditions under which the two approaches coincide and are capable of providing the same constitutive relations are identified. Besides, a commonly used but not often mentioned step in the entropy production maximization is pinpointed and the condition of incompressibility is incorporated into gradient dynamics.

  5. On Maximal Non-Disjoint Families of Subsets

    Directory of Open Access Journals (Sweden)

    Yu. A. Zuev

    2017-01-01

    Full Text Available The paper studies maximal non-disjoint families of subsets of a finite set. Non-disjointness means that any two subsets of a family have a nonempty intersection. The maximality is expressed by the fact that adding a new subset to the family cannot increase its power without violating a non-disjointness condition. Studying the properties of such families is an important section of the extreme theory of sets. Along with purely combinatorial interest, the problems considered here play an important role in informatics, anti-noise coding, and cryptography.In 1961 this problem saw the light of day in the Erdos, Ko and Rado paper, which established a maximum power of the non-disjoint family of subsets of equal power. In 1974 the Erdos and Claytman publication estimated the number of maximal non-disjoint families of subsets without involving the equality of their power. These authors failed to establish an asymptotics of the logarithm of the number of such families when the power of a basic finite set tends to infinity. However, they suggested such an asymptotics as a hypothesis. A.D. Korshunov in two publications in 2003 and 2005 established the asymptotics for the number of non-disjoint families of the subsets of arbitrary powers without maximality condition of these families.The basis for the approach used in the paper to study the families of subsets is their description in the language of Boolean functions. A one-to-one correspondence between a family of subsets and a Boolean function is established by the fact that the characteristic vectors of subsets of a family are considered to be the unit sets of a Boolean function. The main theoretical result of the paper is that the maximal non-disjoint families are in one-to-one correspondence with the monotonic self-dual Boolean functions. When estimating the number of maximal non-disjoint families, this allowed us to use the result of A.A. Sapozhenko, who established the asymptotics of the number of the

  6. Robust ray-tracing algorithms for interactive dose rate evaluation

    International Nuclear Information System (INIS)

    Perrotte, L.

    2011-01-01

    More than ever, it is essential today to develop simulation tools to rapidly evaluate the dose rate received by operators working on nuclear sites. In order to easily study numerous different scenarios of intervention, computation times of available softwares have to be all lowered. This mainly implies to accelerate the geometrical computations needed for the dose rate evaluation. These computations consist in finding and sorting the whole list of intersections between a big 3D scene and multiple groups of 'radiative' rays meeting at the point where the dose has to be measured. In order to perform all these computations in less than a second, we first propose a GPU algorithm that enables the efficient management of one big group of coherent rays. Then we present a modification of this algorithm that guarantees the robustness of the ray-triangle intersection tests through the elimination of the precision issues due to floating-point arithmetic. This modification does not require the definition of scene-dependent coefficients ('epsilon' style) and only implies a small loss of performance (less than 10%). Finally we propose an efficient strategy to handle multiple ray groups (corresponding to multiple radiative objects) which use the previous results.Thanks to these improvements, we are able to perform an interactive and robust dose rate evaluation on big 3D scenes: all of the intersections (more than 13 million) between 700 000 triangles and 12 groups of 100 000 rays each are found, sorted along each ray and transferred to the CPU in 470 milliseconds. (author) [fr

  7. Modification of coaxial Ge/Li detector for low-energy gamma radiation

    International Nuclear Information System (INIS)

    Skrivankova, M.; Seda, J.

    1992-01-01

    A modification is described of a coaxial Ge/Li type ionizing radiation detector which makes possible the detection and spectrometry not only of medium- and high-energy gamma rays but also of low-energy (above 5 keV) X-rays and gamma rays. The modification consists in grinding down a thick diffuse layer of the face, which is subsequently etched in a mixture of nitric and hydrofluoric acids (ratio 5:2 to 1:5). Phosphorus or arsenic is subsequently implanted at an energy of 5 to 30 keV and in a dose of 10 14 to 10 15 ions/cm 2 . The detector is then drifted at 30 to 50 degC for 2 to 20 hours, encased in a cryostat, and submerged into liquid nitrogen. (Z.S.)

  8. Inquiry in bibliography some of the bustan`s maxim

    Directory of Open Access Journals (Sweden)

    sajjad rahmatian

    2016-12-01

    Full Text Available Sa`di is on of those poets who`s has placed a special position to preaching and guiding the people and among his works, allocated throughout the text of bustan to advice and maxim on legal and ethical various subjects. Surely, sa`di on the way of to compose this work and expression of its moral point, direct or indirect have been affected by some previous sources and possibly using their content. The main purpose of this article is that the pay review of basis and sources of bustan`s maxims and show that sa`di when expression the maxims of this work has been affected by which of the texts and works. For this purpose is tried to with search and research on the resources that have been allocated more or less to the aphorisms, to discover and extract traces of influence sa`di from their moral and didactic content. From the most important the finding of this study can be mentioned that indirect effect of some pahlavi books of maxim (like maxims of azarbad marespandan and bozorgmehr book of maxim and also noted sa`di directly influenced of moral and ethical works of poets and writers before him, and of this, sa`di`s influence from abo- shakur balkhi maxims, ferdowsi and keikavus is remarkable and noteworthy.

  9. Can monkeys make investments based on maximized pay-off?

    Directory of Open Access Journals (Sweden)

    Sophie Steelandt

    2011-03-01

    Full Text Available Animals can maximize benefits but it is not known if they adjust their investment according to expected pay-offs. We investigated whether monkeys can use different investment strategies in an exchange task. We tested eight capuchin monkeys (Cebus apella and thirteen macaques (Macaca fascicularis, Macaca tonkeana in an experiment where they could adapt their investment to the food amounts proposed by two different experimenters. One, the doubling partner, returned a reward that was twice the amount given by the subject, whereas the other, the fixed partner, always returned a constant amount regardless of the amount given. To maximize pay-offs, subjects should invest a maximal amount with the first partner and a minimal amount with the second. When tested with the fixed partner only, one third of monkeys learned to remove a maximal amount of food for immediate consumption before investing a minimal one. With both partners, most subjects failed to maximize pay-offs by using different decision rules with each partner' quality. A single Tonkean macaque succeeded in investing a maximal amount to one experimenter and a minimal amount to the other. The fact that only one of over 21 subjects learned to maximize benefits in adapting investment according to experimenters' quality indicates that such a task is difficult for monkeys, albeit not impossible.

  10. Maximal lattice free bodies, test sets and the Frobenius problem

    DEFF Research Database (Denmark)

    Jensen, Anders Nedergaard; Lauritzen, Niels; Roune, Bjarke Hammersholt

    Maximal lattice free bodies are maximal polytopes without interior integral points. Scarf initiated the study of maximal lattice free bodies relative to the facet normals in a fixed matrix. In this paper we give an efficient algorithm for computing the maximal lattice free bodies of an integral m...... method is inspired by the novel algorithm by Einstein, Lichtblau, Strzebonski and Wagon and the Groebner basis approach by Roune....

  11. Disk Density Tuning of a Maximal Random Packing.

    Science.gov (United States)

    Ebeida, Mohamed S; Rushdi, Ahmad A; Awad, Muhammad A; Mahmoud, Ahmed H; Yan, Dong-Ming; English, Shawn A; Owens, John D; Bajaj, Chandrajit L; Mitchell, Scott A

    2016-08-01

    We introduce an algorithmic framework for tuning the spatial density of disks in a maximal random packing, without changing the sizing function or radii of disks. Starting from any maximal random packing such as a Maximal Poisson-disk Sampling (MPS), we iteratively relocate, inject (add), or eject (remove) disks, using a set of three successively more-aggressive local operations. We may achieve a user-defined density, either more dense or more sparse, almost up to the theoretical structured limits. The tuned samples are conflict-free, retain coverage maximality, and, except in the extremes, retain the blue noise randomness properties of the input. We change the density of the packing one disk at a time, maintaining the minimum disk separation distance and the maximum domain coverage distance required of any maximal packing. These properties are local, and we can handle spatially-varying sizing functions. Using fewer points to satisfy a sizing function improves the efficiency of some applications. We apply the framework to improve the quality of meshes, removing non-obtuse angles; and to more accurately model fiber reinforced polymers for elastic and failure simulations.

  12. Decomposition analysis of differential dose volume histograms

    International Nuclear Information System (INIS)

    Heuvel, Frank van den

    2006-01-01

    Dose volume histograms are a common tool to assess the value of a treatment plan for various forms of radiation therapy treatment. The purpose of this work is to introduce, validate, and apply a set of tools to analyze differential dose volume histograms by decomposing them into physically and clinically meaningful normal distributions. A weighted sum of the decomposed normal distributions (e.g., weighted dose) is proposed as a new measure of target dose, rather than the more unstable point dose. The method and its theory are presented and validated using simulated distributions. Additional validation is performed by analyzing simple four field box techniques encompassing a predefined target, using different treatment energies inside a water phantom. Furthermore, two clinical situations are analyzed using this methodology to illustrate practical usefulness. A comparison of a treatment plan for a breast patient using a tangential field setup with wedges is compared to a comparable geometry using dose compensators. Finally, a normal tissue complication probability (NTCP) calculation is refined using this decomposition. The NTCP calculation is performed on a liver as organ at risk in a treatment of a mesothelioma patient with involvement of the right lung. The comparison of the wedged breast treatment versus the compensator technique yields comparable classical dose parameters (e.g., conformity index ≅1 and equal dose at the ICRU dose point). The methodology proposed here shows a 4% difference in weighted dose outlining the difference in treatment using a single parameter instead of at least two in a classical analysis (e.g., mean dose, and maximal dose, or total dose variance). NTCP-calculations for the mesothelioma case are generated automatically and show a 3% decrease with respect to the classical calculation. The decrease is slightly dependant on the fractionation and on the α/β-value utilized. In conclusion, this method is able to distinguish clinically

  13. Local organ dose conversion coefficients for angiographic examinations of coronary arteries

    International Nuclear Information System (INIS)

    Schlattl, H; Zankl, M; Hausleiter, J; Hoeschen, C

    2007-01-01

    New organ dose conversion coefficients for coronary angiographic interventions are presented, as well as dose distributions and resulting maximal local dose conversion coefficients in the relevant organs. For the Monte Carlo based simulations, voxel models of the human anatomy were employed which represent the average Caucasian adult man and woman as defined by the International Commission on Radiological Protection. In the 21 investigated projections, the mean organ dose conversion coefficients vary from a few 0.01 to 2 mGy(Gy cm 2 ) -1 , depending on the projections. However, especially in portions of the lungs and the active bone marrow, the conversion coefficients can locally amount up to 10 mGy(Gy cm 2 ) -1 , which is half the average conversion coefficient of the skin at the field entrance. In addition to the dose conversion coefficients, the dependence of the patient dose on the projection has been estimated. It could be shown that the patient doses are highest for left anterior oblique views with strong caudal or cranial orientation. Nevertheless, for a large range of image-intensifier positions no significant dose differences could be found

  14. An information maximization model of eye movements

    Science.gov (United States)

    Renninger, Laura Walker; Coughlan, James; Verghese, Preeti; Malik, Jitendra

    2005-01-01

    We propose a sequential information maximization model as a general strategy for programming eye movements. The model reconstructs high-resolution visual information from a sequence of fixations, taking into account the fall-off in resolution from the fovea to the periphery. From this framework we get a simple rule for predicting fixation sequences: after each fixation, fixate next at the location that minimizes uncertainty (maximizes information) about the stimulus. By comparing our model performance to human eye movement data and to predictions from a saliency and random model, we demonstrate that our model is best at predicting fixation locations. Modeling additional biological constraints will improve the prediction of fixation sequences. Our results suggest that information maximization is a useful principle for programming eye movements.

  15. Study of dose effect relationship at low doses for non quantitative reactions of skin intestinal mucosa and lung

    International Nuclear Information System (INIS)

    Dutreix, J.; Wambersie, A.

    1977-01-01

    Most of the biological reactions observed in animal experiments or in clinical studies are non quantitative and they only allow assessing an inequality between the effects produced by different irradiations. The method used in non quantitative studies is actually based on the relative contribution of irreparable events and reparable to the cell killing. It provides for the cell population involved in non quantitative biological effects some data which can be expressed in term of a cell survival curve. Such data can be useful in Radiation therapy particularly for maximizing the difference between biological effects by a proper choice of the fraction size. The initial part of the cell survival curve, within the range of doses actually used appears to be a straight exponential. This should allow the extrapolation to very low doses in the range of interest to Radiation Protection

  16. Strategies for dose reduction in ordinary radiographic examinations using CR and DR

    International Nuclear Information System (INIS)

    Willis, C.E.

    2004-01-01

    Uncoupling of display from acquisition in computed radiography (CR) and digital radiography (DR) introduces the potential for systematic overexposure without necessarily compromising image quality. Although the magnitude of radiation doses in general radiography is low compared to computed tomography and fluoroscopy, the dose to the patient is more critical in pediatric examinations than in adults, because of the greater radiosensitivity of children. This manuscript examines a variety of countermeasures for managing radiation doses in pediatric CR and DR examinations, including use of derived exposure indicators, modifications of imaging practice, and development of more efficient radiographic detectors. (orig.)

  17. On the way towards a generalized entropy maximization procedure

    International Nuclear Information System (INIS)

    Bagci, G. Baris; Tirnakli, Ugur

    2009-01-01

    We propose a generalized entropy maximization procedure, which takes into account the generalized averaging procedures and information gain definitions underlying the generalized entropies. This novel generalized procedure is then applied to Renyi and Tsallis entropies. The generalized entropy maximization procedure for Renyi entropies results in the exponential stationary distribution asymptotically for q element of (0,1] in contrast to the stationary distribution of the inverse power law obtained through the ordinary entropy maximization procedure. Another result of the generalized entropy maximization procedure is that one can naturally obtain all the possible stationary distributions associated with the Tsallis entropies by employing either ordinary or q-generalized Fourier transforms in the averaging procedure.

  18. Violating Bell inequalities maximally for two d-dimensional systems

    International Nuclear Information System (INIS)

    Chen Jingling; Wu Chunfeng; Oh, C. H.; Kwek, L. C.; Ge Molin

    2006-01-01

    We show the maximal violation of Bell inequalities for two d-dimensional systems by using the method of the Bell operator. The maximal violation corresponds to the maximal eigenvalue of the Bell operator matrix. The eigenvectors corresponding to these eigenvalues are described by asymmetric entangled states. We estimate the maximum value of the eigenvalue for large dimension. A family of elegant entangled states |Ψ> app that violate Bell inequality more strongly than the maximally entangled state but are somewhat close to these eigenvectors is presented. These approximate states can potentially be useful for quantum cryptography as well as many other important fields of quantum information

  19. The effect of different adaptation strengths on image quality and radiation dose using Siemens care dose 4D

    International Nuclear Information System (INIS)

    Soederberg, M.; Gunnarsson, M.

    2010-01-01

    The purpose of this study was to evaluate the effect of different choices of adaptation strengths on image quality and radiation exposure to the patient with Siemens automatic exposure control system called CARE Dose 4D. An anthropomorphic chest phantom was used to simulate the patient and computed tomography scans were performed with a Siemens SOMATOM Sensation 16 and 64. Owing to adaptation strengths, a considerable reduction (26.6-51.5 % and 27.5-49.5% for Sensation 16 and Sensation 64, respectively) in the radiation dose was found when compared with using a fixed tube current. There was a substantial difference in the image quality (image noise) between the adaptation strengths. Independent of selected adaptation strengths, the level of image noise throughout the chest phantom increased when CARE Dose 4D was used (p < 0.0001). We conclude that the adaptation strengths can be used to obtain user-specified modifications to image quality or radiation exposure to the patient. (authors)

  20. Reactivity improvement of cellulolytic enzyme lignin via mild hydrothermal modification.

    Science.gov (United States)

    Ma, Zhuoming; Tang, Jiafa; Li, Shujun; Suo, Enxiang

    2017-12-01

    Isolated by the cellulolytic enzyme lignin (CEL) process, water-alcohol (1:1, v/v) was introduced as co-solvent in the process of the hydrothermal treatment. The modification parameters such as reaction temperature and time, solid-to-liquid ratio, and catalysts (NaOH and NaOAlO 2 ) have been investigated in terms of the specific lignin properties, such as the phenolic hydroxyl content (OH phen ), DPPH free radical scavenging rate, and formaldehyde value. The CELs were also characterized by GPC, FT-IR and 1 H NMR spectroscopy, and Py-GC/MS. The key data are under optimal lignin modification conditions (solid-to-liquid ratio of 1:10 (w/v) and a temperature of 250°C for 60min) are: OH phen content: 2.50mmol/g; half maximal inhibitory concentration (IC 50 ) towards DPPH free radicals: 88.2mg/L; formaldehyde value: 446.9g/kg). Both base catalysts decrease the residue rate, but phenol reactivities of the products were also detracted. Py-GC/MS results revealed that modified lignin had a higher phenolic composition than the CEL did, especially the modified lignin without catalyst (ML), which represented 74.51% phenolic content. Copyright © 2017. Published by Elsevier Inc.

  1. Actual trends in patients dose reduction in radiodiagnostic

    International Nuclear Information System (INIS)

    Nikodemova, D.; Gomola, I.; Horvathova, M.

    2001-01-01

    In our contribution we tried to survey the entrance surface doses, as well as dose area product measurements by studying 3 types of radiodiagnostic examinations (mammography, chest examination of children and fluoroscopy). The analysis of the obtained data and their comparison with reference values of European Union has demonstrated the significant role of radiation protection dosimetry as an integral part of quality assurance strategy in radiology. Optimisation in radiodiagnostic requires fulfilling the following criteria: - patient doses to be in accordance with accepted diagnostic practice; - patient doses to be as low as reasonably practicable in order to achieve the required diagnostic results; - professionals clinically and physically directing medical exposures to be familiar with typical doses, methods of measurements and means of dose reduction. One of the basic requirements for continuous quality improvement is the repeating cycle of patient dose measurements for determining the level of risk associated with particular radiological examination at given radiodiagnostic department. Beside the undeniable positive influence of Quality Assurance (QA) procedures possible negative effects should be avoided. The danger exist that the development of new techniques is slowed down by standardising all procedures and wide agreement in implementing of required modifications. Reaching of a consensus of a certain procedure became therefore a labour intensive and time-consuming process. (authors)

  2. A comparison of maximal exercise and dipyridamole thallium-201 planar gated scintigraphy

    International Nuclear Information System (INIS)

    Martin, W.; Tweddel, A.C.; Main, G.; Hutton, I.

    1992-01-01

    Both symptom-limited maximal exercise and intravenously given dipyridamole stress (0.56 mg/kg over 4 min with a 2 min walk) gated thallium scans were performed in 22 patients undergoing coronary arteriography for the assessment of chest pain. All scans were acquired gated to the electrocardiogram in 3 projections and were reported for the presence and extent of defects in 5 myocardial segments in each view. In addition, left and right ventricular myocardial uptake and estimates of right and left lung and liver to left ventricular uptake were assessed relative to the injected dose of thallium-201. Overall, 190/310 segments were abnormal with exercise compared with 169/310 with dipyridamole. Segments were scored greater in extent in 90/310 cases with exercise, compared with 46/310 in which the defect was more extensive with dipyridamole. Non-attenuation corrected percentage myocardial thallium uptakes were similar for both stresses. Left and right lung and liver to left ventricle ratios were all significantly higher with dipyridamole than with exercise. High right and left lung uptakes with dipyridamole were strongly correlated with high exercise values. The liver uptake was weakly correlated between the 2 different stress tests. These results demonstrate that dipyridamole induces fewer and less extensive thallium perfusion defects than maximal exercise, and that liver and lung to myocardial ratios are higher with dipyridamole than with exercise. (orig./MG)

  3. OEDIPE, a software for personalized Monte Carlo dosimetry and treatment planning optimization in nuclear medicine: absorbed dose and biologically effective dose considerations

    International Nuclear Information System (INIS)

    Petitguillaume, A.; Broggio, D.; Franck, D.; Desbree, A.; Bernardini, M.; Labriolle Vaylet, C. de

    2014-01-01

    For targeted radionuclide therapies, treatment planning usually consists of the administration of standard activities without accounting for the patient-specific activity distribution, pharmacokinetics and dosimetry to organs at risk. The OEDIPE software is a user-friendly interface which has an automation level suitable for performing personalized Monte Carlo 3D dosimetry for diagnostic and therapeutic radionuclide administrations. Mean absorbed doses to regions of interest (ROIs), isodose curves superimposed on a personalized anatomical model of the patient and dose-volume histograms can be extracted from the absorbed dose 3D distribution. Moreover, to account for the differences in radiosensitivity between tumoral and healthy tissues, additional functionalities have been implemented to calculate the 3D distribution of the biologically effective dose (BED), mean BEDs to ROIs, isoBED curves and BED-volume histograms along with the Equivalent Uniform Biologically Effective Dose (EUD) to ROIs. Finally, optimization tools are available for treatment planning optimization using either the absorbed dose or BED distributions. These tools enable one to calculate the maximal injectable activity which meets tolerance criteria to organs at risk for a chosen fractionation protocol. This paper describes the functionalities available in the latest version of the OEDIPE software to perform personalized Monte Carlo dosimetry and treatment planning optimization in targeted radionuclide therapies. (authors)

  4. Laser surface modification of ultra-high-molecular-weight polyethylene (UHMWPE) for biomedical applications

    International Nuclear Information System (INIS)

    Riveiro, A.; Soto, R.; Val, J. del; Comesaña, R.; Boutinguiza, M.; Quintero, F.; Lusquiños, F.; Pou, J.

    2014-01-01

    Ultra-high-molecular-weight polyethylene (UHMWPE) is a synthetic polymer used for biomedical applications because of its high impact resistance, ductility and stability in contact with physiological fluids. Therefore, this material is being used in human orthopedic implants such as total hip or knee replacements. Surface modification of this material relates to changes on its chemistry, microstructure, roughness, and topography, all influencing its biological response. Surface treatment of UHMWPE is very difficult due to its high melt viscosity. This work presents a systematic approach to discern the role of different laser wavelengths (λ = 1064, 532, and 355 nm) on the surface modification of carbon coated UHMWPE samples. Influence of laser processing conditions (irradiance, pulse frequency, scanning speed, and spot overlapping) on the surface properties of this material was determined using an advanced statistical planning of experiments. A full factorial design of experiments was used to find the main effects of the processing parameters. The obtained results indicate the way to maximize surface properties which largely influence cell–material interaction.

  5. Laser surface modification of ultra-high-molecular-weight polyethylene (UHMWPE) for biomedical applications

    Energy Technology Data Exchange (ETDEWEB)

    Riveiro, A., E-mail: ariveiro@uvigo.es [Applied Physics Department, University of Vigo, ETSII, Lagoas-Marcosende, 9, Vigo 36310 (Spain); Centro Universitario de la Defensa, Escuela Naval Militar, Plaza de España 2, 36920 Marín (Spain); Soto, R.; Val, J. del; Comesaña, R.; Boutinguiza, M.; Quintero, F.; Lusquiños, F.; Pou, J. [Applied Physics Department, University of Vigo, ETSII, Lagoas-Marcosende, 9, Vigo 36310 (Spain)

    2014-05-01

    Ultra-high-molecular-weight polyethylene (UHMWPE) is a synthetic polymer used for biomedical applications because of its high impact resistance, ductility and stability in contact with physiological fluids. Therefore, this material is being used in human orthopedic implants such as total hip or knee replacements. Surface modification of this material relates to changes on its chemistry, microstructure, roughness, and topography, all influencing its biological response. Surface treatment of UHMWPE is very difficult due to its high melt viscosity. This work presents a systematic approach to discern the role of different laser wavelengths (λ = 1064, 532, and 355 nm) on the surface modification of carbon coated UHMWPE samples. Influence of laser processing conditions (irradiance, pulse frequency, scanning speed, and spot overlapping) on the surface properties of this material was determined using an advanced statistical planning of experiments. A full factorial design of experiments was used to find the main effects of the processing parameters. The obtained results indicate the way to maximize surface properties which largely influence cell–material interaction.

  6. Oxidative modification of ferritin induced by methylglyoxal

    Directory of Open Access Journals (Sweden)

    Sung Ho An

    2012-03-01

    Full Text Available Methylglyoxal (MG was identified as an intermediate innon-enzymatic glycation and increased levels were reported inpatients with diabetes. In this study, we evaluated the effects ofMG on the modification of ferritin. When ferritin wasincubated with MG, covalent crosslinking of the proteinincreased in a time- and MG dose-dependent manner.Reactive oxygen species (ROS scavengers, N-acetyl-L-cysteineand thiourea suppressed the MG-mediated ferritinmodification. The formation of dityrosine was observed inMG-mediated ferritin aggregates and ROS scavengers inhibitedthe formation of dityrosine. During the reaction betweenferritin and MG, the generation of ROS was increased as afunction of incubation time. These results suggest that ROSmay play a role in the modification of ferritin by MG. Thereaction between ferritin and MG led to the release of ironions from the protein. Ferritin exposure to MG resulted in aloss of arginine, histidine and lysine residues. It was assumedthat oxidative damage to ferritin caused by MG may induce anincrease in the iron content in cells, which is deleterious tocells. This mechanism, in part, may provide an explanation orthe deterioration of organs under diabetic conditions. [BMBreports 2012; 45(3: 147-152

  7. Final Report - Epigenetics of low dose radiation effects in an animal model

    Energy Technology Data Exchange (ETDEWEB)

    Kovalchuk, Olga

    2014-10-22

    This project sought mechanistic understanding of the epigenetic response of tissues as well as the consequences of those responses, when induced by low dose irradiation in a well-established model system (mouse). Based on solid and extensive preliminary data we investigated the molecular epigenetic mechanisms of in vivo radiation responses, particularly – effects of low, occupationally relevant radiation exposures on the genome stability and adaptive response in mammalian tissues and organisms. We accumulated evidence that low dose irradiation altered epigenetic profiles and impacted radiation target organs of the exposed animals. The main long-term goal was to dissect the epigenetic basis of induction of the low dose radiation-induced genome instability and adaptive response and the specific fundamental roles of epigenetic changes (i.e. DNA methylation, histone modifications and miRNAs) in their generation. We hypothesized that changes in global and regional DNA methylation, global histone modifications and regulatory microRNAs played pivotal roles in the generation and maintenance low-dose radiation-induced genome instability and adaptive response. We predicted that epigenetic changes influenced the levels of genetic rearrangements (transposone reactivation). We hypothesized that epigenetic responses from low dose irradiation were dependent on exposure regimes, and would be greatest when organisms are exposed in a protracted/fractionated manner: fractionated exposures > acute exposures. We anticipated that the epigenetic responses were correlated with the gene expression levels. Our immediate objectives were: • To investigate the exact nature of the global and locus-specific DNA methylation changes in the LDR exposed cells and tissues and dissect their roles in adaptive response • To investigate the roles of histone modifications in the low dose radiation effects and adaptive response • To dissect the roles of regulatory microRNAs and their targets in low

  8. Real-time topic-aware influence maximization using preprocessing.

    Science.gov (United States)

    Chen, Wei; Lin, Tian; Yang, Cheng

    2016-01-01

    Influence maximization is the task of finding a set of seed nodes in a social network such that the influence spread of these seed nodes based on certain influence diffusion model is maximized. Topic-aware influence diffusion models have been recently proposed to address the issue that influence between a pair of users are often topic-dependent and information, ideas, innovations etc. being propagated in networks are typically mixtures of topics. In this paper, we focus on the topic-aware influence maximization task. In particular, we study preprocessing methods to avoid redoing influence maximization for each mixture from scratch. We explore two preprocessing algorithms with theoretical justifications. Our empirical results on data obtained in a couple of existing studies demonstrate that one of our algorithms stands out as a strong candidate providing microsecond online response time and competitive influence spread, with reasonable preprocessing effort.

  9. Modeling the violation of reward maximization and invariance in reinforcement schedules.

    Directory of Open Access Journals (Sweden)

    Giancarlo La Camera

    2008-08-01

    Full Text Available It is often assumed that animals and people adjust their behavior to maximize reward acquisition. In visually cued reinforcement schedules, monkeys make errors in trials that are not immediately rewarded, despite having to repeat error trials. Here we show that error rates are typically smaller in trials equally distant from reward but belonging to longer schedules (referred to as "schedule length effect". This violates the principles of reward maximization and invariance and cannot be predicted by the standard methods of Reinforcement Learning, such as the method of temporal differences. We develop a heuristic model that accounts for all of the properties of the behavior in the reinforcement schedule task but whose predictions are not different from those of the standard temporal difference model in choice tasks. In the modification of temporal difference learning introduced here, the effect of schedule length emerges spontaneously from the sensitivity to the immediately preceding trial. We also introduce a policy for general Markov Decision Processes, where the decision made at each node is conditioned on the motivation to perform an instrumental action, and show that the application of our model to the reinforcement schedule task and the choice task are special cases of this general theoretical framework. Within this framework, Reinforcement Learning can approach contextual learning with the mixture of empirical findings and principled assumptions that seem to coexist in the best descriptions of animal behavior. As examples, we discuss two phenomena observed in humans that often derive from the violation of the principle of invariance: "framing," wherein equivalent options are treated differently depending on the context in which they are presented, and the "sunk cost" effect, the greater tendency to continue an endeavor once an investment in money, effort, or time has been made. The schedule length effect might be a manifestation of these

  10. Cardiorespiratory Coordination in Repeated Maximal Exercise

    Directory of Open Access Journals (Sweden)

    Sergi Garcia-Retortillo

    2017-06-01

    Full Text Available Increases in cardiorespiratory coordination (CRC after training with no differences in performance and physiological variables have recently been reported using a principal component analysis approach. However, no research has yet evaluated the short-term effects of exercise on CRC. The aim of this study was to delineate the behavior of CRC under different physiological initial conditions produced by repeated maximal exercises. Fifteen participants performed 2 consecutive graded and maximal cycling tests. Test 1 was performed without any previous exercise, and Test 2 6 min after Test 1. Both tests started at 0 W and the workload was increased by 25 W/min in males and 20 W/min in females, until they were not able to maintain the prescribed cycling frequency of 70 rpm for more than 5 consecutive seconds. A principal component (PC analysis of selected cardiovascular and cardiorespiratory variables (expired fraction of O2, expired fraction of CO2, ventilation, systolic blood pressure, diastolic blood pressure, and heart rate was performed to evaluate the CRC defined by the number of PCs in both tests. In order to quantify the degree of coordination, the information entropy was calculated and the eigenvalues of the first PC (PC1 were compared between tests. Although no significant differences were found between the tests with respect to the performed maximal workload (Wmax, maximal oxygen consumption (VO2 max, or ventilatory threshold (VT, an increase in the number of PCs and/or a decrease of eigenvalues of PC1 (t = 2.95; p = 0.01; d = 1.08 was found in Test 2 compared to Test 1. Moreover, entropy was significantly higher (Z = 2.33; p = 0.02; d = 1.43 in the last test. In conclusion, despite the fact that no significant differences were observed in the conventionally explored maximal performance and physiological variables (Wmax, VO2 max, and VT between tests, a reduction of CRC was observed in Test 2. These results emphasize the interest of CRC

  11. The effects of size and surface modification of amorphous silica particles on biodistribution and liver metabolism in mice

    Science.gov (United States)

    Lu, Xiaoyan; Ji, Cai; Jin, Tingting; Fan, Xiaohui

    2015-05-01

    Engineered nanoparticles, with unconventional properties, are promising platforms for biomedical applications. Since they may interact with a wide variety of biomolecules, it is critical to understand the impact of the physicochemical properties of engineered nanoparticles on biological systems. In this study, the effects of particle size and surface modification alone or in combination of amorphous silica particles (SPs) on biological responses were determined using a suite of general toxicological assessments and metabonomics analysis in mice model. Our results suggested that amino or carboxyl surface modification mitigated the liver toxicity of plain-surface SPs. 30 nm SPs with amino surface modification were found to be the most toxic SPs among all the surface-modified SP treatments at the same dosage. When treatment dose was increased, submicro-sized SPs with amino or carboxyl surface modification also induced liver toxicity. Biodistribution studies suggested that 70 nm SPs were mainly accumulated in liver and spleen regardless of surface modifications. Interestingly, these two organs exhibited different uptake trends. Furthermore, metabonomics studies indicated that surface modification plays a more dominant role to affect the liver metabolism than particle size.

  12. The effect of caffeine on maximal oxygen uptake and vertical jump performance in male basketball players.

    Science.gov (United States)

    Tucker, Matthew A; Hargreaves, Jill M; Clarke, Jenny C; Dale, Darren L; Blackwell, Gavin J

    2013-02-01

    This study investigated whether performance enhancement from caffeine described by other researchers transfers to male basketball players. The effects of caffeine ingestion were studied in a maximal-effort test on a treadmill that was followed by a vertical-jump test. Five elite-level male basketball players completed a graded treadmill test that measured maximal oxygen uptake, blood lactate profiles, respiratory exchange ratio, and rating of perceived exertion at each 3-minute stage. After a 15-minute warm-down, the subjects performed 10 vertical rebound jumps. Each subject completed the test twice--once with a 3 mg·kg(-1) of body weight dose of caffeine and once with a placebo, with the dosage administered 60 minutes before commencement of exercise. The test was thus administered according to a double-blind protocol. No substantial trends were found between caffeine and control trials, regardless of trial order. The study showed that the specified dosage had negligible effects on the players' power and endurance performance and had no efficacy as an ergogenic aid for male basketball players.

  13. El culto de Maximón en Guatemala

    OpenAIRE

    Pédron‑Colombani, Sylvie

    2009-01-01

    Este artículo se enfoca en la figura de Maximón, deidad sincrética de Guatemala, en un contexto de desplazamiento de la religión católica popular por parte de las iglesias protestantes. Esta divinidad híbrida a la cual se agregan santos católicos como Judas Iscariote o el dios maya Mam, permite la apropiación de Maximón por segmentos diferenciados de la población (tanto indígena como mestiza). Permite igualmente ser símbolo de protestas sociales enmascaradas cuando se asocia Maximón con figur...

  14. Physical Activity Targeted at Maximal Lipid Oxidation: A Meta-Analysis

    Directory of Open Access Journals (Sweden)

    A. J. Romain

    2012-01-01

    Full Text Available Exercise is recognized as a part of the management of obesity and diabetes. Various protocols of exercise are proposed for the management of obesity, diabetes, and other metabolic diseases. One of the strategies proposed by several authors is low intensity endurance training targeted at the level of maximal oxidation. Large series using this technique are lacking. Addressing this issue, we performed a meta-analysis of the studies on anthropometric measurements. From a database of 433 articles, 15 were selected, including 279 subjects with 6 different populations. Studies duration ranged from 2 months to 12 months. Concerning weight loss, in the intervention versus control analysis, five studies with 185 participants were included with a significant effect size favors exercise (P=0.02 without significant heterogeneity (I2=0.0%, P=0.83. Further randomized controlled trials for comparing it with other exercise protocols and defining its dose effectiveness on large samples are needed.

  15. Bioavailability of diclofenac potassium at low doses

    Science.gov (United States)

    Hinz, Burkhard; Chevts, Julia; Renner, Bertold; Wuttke, Henrike; Rau, Thomas; Schmidt, Andreas; Szelenyi, Istvan; Brune, Kay; Werner, Ulrike

    2005-01-01

    Aim Diclofenac-K has been recently launched at low oral doses in different countries for over-the-counter use. However, given the considerable first-pass metabolism of diclofenac, the degree of absorption of diclofenac-K at low doses remained to be determined. The aim of this study was to determine the bioavailability of low-dose diclofenac-K. Methods A randomized, three-way, cross-over study was performed in 10 subjects. Each received diclofenac-K, 22.5 mg via short-term i.v. infusion and orally at single doses of 12.5 mg and 25 mg. Results Mean (± SD) times to maximal plasma concentration (tmax) of diclofenac were 0.48 ± 0.28 h (12.5 mg) and 0.93 ± 0.96 h (25 mg). The absolute bioavailability of diclofenac-K after oral administration did not differ significantly in the 12.5-mg and 25-mg dose group (63.1 ± 12.6% vs. 65.1 ± 19.4%, respectively). The 90% confidence intervals for the AUC∞ and AUCt ratios for the two oral regimes were 82.6, 103.4% (point estimate 92.4%) and 86.2, 112.9% (point estimate 98.6%), respectively. These values were within the acceptance criteria for bioequivalence (80–125%). Conclusions Our data indicate that diclofenac-K is rapidly and well absorbed at low dose, and are consistent with a rapid onset of action of the drug. Abbreviations AUC, area under plasma concentraton-time curve; Cmax, peak plasma concentration; CI, confidence interval; COX, cyclooxygenase; D, dose; F, absolute bioavailability; tmax, time to reach Cmax. PMID:15606444

  16. Self-consistent collective-coordinate method for ''maximally-decoupled'' collective subspace and its boson mapping: Quantum theory of ''maximally-decoupled'' collective motion

    International Nuclear Information System (INIS)

    Marumori, T.; Sakata, F.; Maskawa, T.; Une, T.; Hashimoto, Y.

    1983-01-01

    The main purpose of this paper is to develop a full quantum theory, which is capable by itself of determining a ''maximally-decoupled'' collective motion. The paper is divided into two parts. In the first part, the motivation and basic idea of the theory are explained, and the ''maximal-decoupling condition'' on the collective motion is formulated within the framework of the time-dependent Hartree-Fock theory, in a general form called the invariance principle of the (time-dependent) Schrodinger equation. In the second part, it is shown that when the author positively utilize the invariance principle, we can construct a full quantum theory of the ''maximally-decoupled'' collective motion. This quantum theory is shown to be a generalization of the kinematical boson-mapping theories so far developed, in such a way that the dynamical ''maximal-decoupling condition'' on the collective motion is automatically satisfied

  17. Dose- and time-dependent pharmacokinetics of apigenin trimethyl ether.

    Science.gov (United States)

    Elhennawy, Mai Gamal; Lin, Hai-Shu

    2018-06-15

    Apigenin trimethyl ether (5,7,4'-trimethoxyflavone, ATE), one of the key polymethoxyflavones present in black ginger (rhizome of Kaempferia parviflora) possesses various health-promoting activities. To optimize its medicinal application, the pharmacokinetics of ATE was assessed in Sprague-Dawley rats with emphases to identify the impacts from dose and repeated dosing on its major pharmacokinetic parameters. Plasma ATE levels were monitored by liquid chromatography-tandem mass spectrometry (LC-MS/MS) method. Upon single intravenous administration (2 mg/kg), plasma levels of ATE declined through an apparent first-order process while dose-escalation to 4 and 8 mg/kg led to its non-linear disposition, which could be described by the Michaelis-Menten model. Similarly, dose-dependent oral pharmacokinetics was confirmed and when the dose was escalated from 5 to 15 and 45 mg/kg, much longer mean residence time (MRT 0→last ), higher dose-normalized maximal plasma concentration (C max /Dose) and exposure (AUC/Dose) were observed at 15 and/or 45 mg/kg. One-week daily oral administration of ATE at 15 mg/kg caused its accelerated elimination and the plasma exposure (AUC) after intravenous (2 mg/kg) and oral administration (15 mg/kg) dropped ~40 and 60%, respectively. As ATE displayed both dose- and time-dependent pharmacokinetics, caution is needed in the medicinal applications of ATE and/or black ginger. Copyright © 2018 Elsevier B.V. All rights reserved.

  18. A feasibility assessment of calculation procedure with case study and the modification of dose conversion factor in STARDOSE

    International Nuclear Information System (INIS)

    Ko, H. S.; Jang, M.; Kim, S. H.; Kang, C. S.

    2003-01-01

    STARDOSE computer code is the designed code for which is calculated the dose of control room and off-site dose on design basis accident of nuclear power plant. Input files of STARDOSE are libfile1.txt which has decay constant and dose conversion factor, and input.dat which structurally expresses the real plant model by editor. It is given much advanced result with using newer dose conversion factor in libfile1.txt. In this study, therefore, case study is performed that is made input.dat file for LOCA and libfile1.txt which is included newer dose conversion factor and core inventory on APR-1400 and UCN 5 and 6. The result of case study is compared and analyzed

  19. Enhancement of Transistor-to-Transistor Variability Due to Total Dose Effects in 65-nm MOSFETs

    CERN Document Server

    Gerardin, S; Cornale, D; Ding, L; Mattiazzo, S; Paccagnella, A; Faccio, F; Michelis, S

    2015-01-01

    We studied device-to-device variations as a function of total dose in MOSFETs, using specially designed test structures and procedures aimed at maximizing matching between transistors. Degradation in nMOSFETs is less severe than in pMOSFETs and does not show any clear increase in sample-to-sample variability due to the exposure. At doses smaller than 1 Mrad( SiO2) variability in pMOSFETs is also practically unaffected, whereas at very high doses-in excess of tens of Mrad( SiO2)-variability in the on-current is enhanced in a way not correlated to pre-rad variability. The phenomenon is likely due to the impact of random dopant fluctuations on total ionizing dose effects.

  20. Dose-effect relationship for cataract induction after single-dose total body irradiation and bone marrow transplantation for acute leukemia

    International Nuclear Information System (INIS)

    Kempen-Harteveld, M. Loes van; Belkacemi, Yazid; Kal, Henk B.; Labopin, Myriam; Frassoni, Francesco

    2002-01-01

    Purpose: To determine a dose-effect relationship for cataract induction, the tissue-specific parameter, α/β, and the rate of repair of sublethal damage, μ value, in the linear-quadratic formula have to be known. To obtain these parameters for the human eye lens, a large series of patients treated with different doses and dose rates is required. The data of patients with acute leukemia treated with single-dose total body irradiation (STBI) and bone marrow transplantation (BMT) collected by the European Group for Blood and Marrow Transplantation were analyzed. Methods and Materials: The data of 495 patients who underwent BMT for acute leukemia, who had STBI as part of their conditioning regimen, were analyzed using the linear-quadratic concept. The end point was the incidence of cataract formation after BMT. Of the analyzed patients, 175 were registered as having cataracts. Biologic effective doses (BEDs) for different sets of values for α/β and μ were calculated for each patient. With Cox regression analysis, using the overall chi-square test as the parameter evaluating the goodness of fit, α/β and μ values were found. Risk factors for cataract induction were the BED of the applied TBI regimen, allogeneic BMT, steroid therapy for >14 weeks, and heparin administration. To avoid the influence of steroid therapy and heparin on cataract induction, patients who received steroid or heparin treatment were excluded, leaving only the BED as a risk factor. Next, the most likely set of α/β and μ values was obtained. With this set, the cataract-free survival rates were calculated for specific BED intervals, according to the Kaplan-Meier method. From these calculations, cataract incidences were obtained as function of the BED at 120 months after STBI. Results: The use of BED instead of the TBI dose enabled the incidence of cataract formation to be predicted in a reasonably consistent way. With Cox regression analysis for all STBI data, a maximal chi-square value was

  1. Low-dose myocardial blood flow imaging using 82Rb-PET (RUBILOW 2.0)

    DEFF Research Database (Denmark)

    Hoff, Camilla Molich; Tolbod, Lars Poulsen; Harms, Hans

    2017-01-01

    Aim: Relative and absolute measures of myocardial blood flow (MBF) can be derived from a 82Rb PET/CT scan using list mode data to extract static, gated and dynamic PET series. High doses of 82Rb are used to maximize image quality in especially static images. High doses require large eluate volumes......, may degrade scanner dead time performance at first pass and decreases generator lifetime. Lower doses will expand the availability of 82Rb PET/CT and lower doses to personnel and patients. The aim of the current study was to examine MBF with a low dose (LD) 82Rb protocol compared to the institution......’s standard (STD) protocol. Methods: Twenty-one patients referred to 82Rb PET were included in the study. Patients were examined during rest and stress with repeated LD (740 MBq) and STD dose (1110 MBq) Rb-PET during the same imaging session. Regional and global rest and stress MBF values, total perfusion...

  2. Consequences of additional use of PET information for target volume delineation and radiotherapy dose distribution for esophageal cancer

    International Nuclear Information System (INIS)

    Muijs, Christina T.; Schreurs, Liesbeth M.; Busz, Dianne M.; Beukema, Jannet C.; Borden, Arnout J. van der; Pruim, Jan; Van der Jagt, Eric J.; Plukker, John Th.; Langendijk, Johannes A.

    2009-01-01

    Background and purpose: To determine the consequences of target volume (TV) modifications, based on the additional use of PET information, on radiation planning, assuming PET/CT-imaging represents the true extent of the tumour. Materials and methods: For 21 patients with esophageal cancer, two separate TV's were retrospectively defined based on CT (CT-TV) and co-registered PET/CT images (PET/CT-TV). Two 3D-CRT plans (prescribed dose 50.4 Gy) were constructed to cover the corresponding TV's. Subsequently, these plans were compared for target coverage, normal tissue dose-volume histograms and the corresponding normal tissue complication probability (NTCP) values. Results: The addition of PET led to the modification of CT-TV with at least 10% in 12 of 21 patients (57%) (reduction in 9, enlargement in 3). PET/CT-TV was inadequately covered by the CT-based treatment plan in 8 patients (36%). Treatment plan modifications resulted in significant changes (p < 0.05) in dose distributions to heart and lungs. Corresponding changes in NTCP values ranged from -3% to +2% for radiation pneumonitis and from -0.2% to +1.2% for cardiac mortality. Conclusions: This study demonstrated that TV's based on CT might exclude PET-avid disease. Consequences are under dosing and thereby possibly ineffective treatment. Moreover, the addition of PET in radiation planning might result in clinical important changes in NTCP.

  3. Comparative study of radiological impact of nuclear power plant and coal-fired power plant: estimation of radiation dose to public from nuclear power plant and coal-fired power plant generation

    International Nuclear Information System (INIS)

    Umbara, Heru; Yatim, Sofyan

    1998-01-01

    Radiation impact assessment of Nuclear Power Plant and Coal-Fired Power Plant in Muria Penninsula was carried out. The computation of radionuclide releases to the atmosphere subjects to gaussian plume model, on the other hand, the radionuclide transfer model between environmental compartment (pathway) follow concentration factor methods. Both models are compiled in GENII-The Hanford Environmental Radiation Dosimetry Software System, which is used in the assessment. Most of all input data for GENII package are site specific, such as meteorological data, stack flow, stack height, population, local consumption except the transfer factor data are taken from the GENII package. The results show that during operation of NPP the maximal exposed individual received annual effective dose 150 nSv at 300 -700 m from the site toward east otherwise in operation of CPP the maximal exposed individual received annual effective dose 410 nSv in the same distance and direction. Both results of the maximal exposed individual received annual effective dose about 0,003 % and 0,008 % of whole body annual dose limit for members of public for NPP and CPP. (author)

  4. Assessment of the Maximal Split-Half Coefficient to Estimate Reliability

    Science.gov (United States)

    Thompson, Barry L.; Green, Samuel B.; Yang, Yanyun

    2010-01-01

    The maximal split-half coefficient is computed by calculating all possible split-half reliability estimates for a scale and then choosing the maximal value as the reliability estimate. Osburn compared the maximal split-half coefficient with 10 other internal consistency estimates of reliability and concluded that it yielded the most consistently…

  5. SYNCHRONIZATION OF HETEROGENEOUS OSCILLATORS UNDER NETWORK MODIFICATIONS: PERTURBATION AND OPTIMIZATION OF THE SYNCHRONY ALIGNMENT FUNCTION

    Science.gov (United States)

    Taylor, Dane; Skardal, Per Sebastian; Sun, Jie

    2016-01-01

    Synchronization is central to many complex systems in engineering physics (e.g., the power-grid, Josephson junction circuits, and electro-chemical oscillators) and biology (e.g., neuronal, circadian, and cardiac rhythms). Despite these widespread applications—for which proper functionality depends sensitively on the extent of synchronization—there remains a lack of understanding for how systems can best evolve and adapt to enhance or inhibit synchronization. We study how network modifications affect the synchronization properties of network-coupled dynamical systems that have heterogeneous node dynamics (e.g., phase oscillators with non-identical frequencies), which is often the case for real-world systems. Our approach relies on a synchrony alignment function (SAF) that quantifies the interplay between heterogeneity of the network and of the oscillators and provides an objective measure for a system’s ability to synchronize. We conduct a spectral perturbation analysis of the SAF for structural network modifications including the addition and removal of edges, which subsequently ranks the edges according to their importance to synchronization. Based on this analysis, we develop gradient-descent algorithms to efficiently solve optimization problems that aim to maximize phase synchronization via network modifications. We support these and other results with numerical experiments. PMID:27872501

  6. Learning curves for mutual information maximization

    International Nuclear Information System (INIS)

    Urbanczik, R.

    2003-01-01

    An unsupervised learning procedure based on maximizing the mutual information between the outputs of two networks receiving different but statistically dependent inputs is analyzed [S. Becker and G. Hinton, Nature (London) 355, 161 (1992)]. For a generic data model, I show that in the large sample limit the structure in the data is recognized by mutual information maximization. For a more restricted model, where the networks are similar to perceptrons, I calculate the learning curves for zero-temperature Gibbs learning. These show that convergence can be rather slow, and a way of regularizing the procedure is considered

  7. Patient dose rate: An ultimate limit for spatial and density resolution of scanning systems

    International Nuclear Information System (INIS)

    Kowalski, G.; Wagner, W.

    1979-01-01

    In X-ray scanning systems, picture quality of the reconstructed slices is limited to a maximum spatial as well as density resolution by the applied radiation dose. Density resolution can be improved in proportion to the root of the patient dose, whereas a doubled spatial resolving power requires an eight times higher patient dose, assuming a fixed slice thickness. Only a careful trade-off between the applied patient dose, density resolution and spatial resolution yields a maximal diagnostic value for the physician. Specifications of a scanning system have to take into account these ultimate restrictions, so that picture quality really is limited by the patient's dose rather than by technical constraints. In addition a method is given by which the applied dose can be reduced by focusing the main intensity onto the region of interest, in case that region is known a priori. (orig.) [de

  8. Breakdown of maximality conjecture in continuous phase transitions

    International Nuclear Information System (INIS)

    Mukamel, D.; Jaric, M.V.

    1983-04-01

    A Landau-Ginzburg-Wilson model associated with a single irreducible representation which exhibits an ordered phase whose symmetry group is not a maximal isotropy subgroup of the symmetry group of the disordered phase is constructed. This example disproves the maximality conjecture suggested in numerous previous studies. Below the (continuous) transition, the order parameter points along a direction which varies with the temperature and with the other parameters which define the model. An extension of the maximality conjecture to reducible representations was postulated in the context of Higgs symmetry breaking mechanism. Our model can also be extended to provide a counter example in these cases. (author)

  9. Maximizers versus satisficers: Decision-making styles, competence, and outcomes

    OpenAIRE

    Andrew M. Parker; Wändi Bruine de Bruin; Baruch Fischhoff

    2007-01-01

    Our previous research suggests that people reporting a stronger desire to maximize obtain worse life outcomes (Bruine de Bruin et al., 2007). Here, we examine whether this finding may be explained by the decision-making styles of self-reported maximizers. Expanding on Schwartz et al.\\ (2002), we find that self-reported maximizers are more likely to show problematic decision-making styles, as evidenced by self-reports of less behavioral coping, greater dependence on others when making decision...

  10. Mutation induction in haploid yeast after split-dose radiation-exposure. I. Fractionated UV-irradiation.

    Science.gov (United States)

    Schenk, K; Zölzer, F; Kiefer, J

    1989-01-01

    Mutation induction was investigated in wild-type haploid yeast Saccharomyces cerevisiae after split-dose UV-irradiation. Cells were exposed to fractionated 254 nm-UV-doses separated by intervals from 0 to 6 h with incubation either on non-nutrient or nutrient agar between. The test parameter was resistance to canavanine. If modifications of sensitivity due to incubation are appropriately taken into account there is no change of mutation frequency.

  11. IMNN: Information Maximizing Neural Networks

    Science.gov (United States)

    Charnock, Tom; Lavaux, Guilhem; Wandelt, Benjamin D.

    2018-04-01

    This software trains artificial neural networks to find non-linear functionals of data that maximize Fisher information: information maximizing neural networks (IMNNs). As compressing large data sets vastly simplifies both frequentist and Bayesian inference, important information may be inadvertently missed. Likelihood-free inference based on automatically derived IMNN summaries produces summaries that are good approximations to sufficient statistics. IMNNs are robustly capable of automatically finding optimal, non-linear summaries of the data even in cases where linear compression fails: inferring the variance of Gaussian signal in the presence of noise, inferring cosmological parameters from mock simulations of the Lyman-α forest in quasar spectra, and inferring frequency-domain parameters from LISA-like detections of gravitational waveforms. In this final case, the IMNN summary outperforms linear data compression by avoiding the introduction of spurious likelihood maxima.

  12. Neutrino mass textures with maximal CP violation

    International Nuclear Information System (INIS)

    Aizawa, Ichiro; Kitabayashi, Teruyuki; Yasue, Masaki

    2005-01-01

    We show three types of neutrino mass textures, which give maximal CP violation as well as maximal atmospheric neutrino mixing. These textures are described by six real mass parameters: one specified by two complex flavor neutrino masses and two constrained ones and the others specified by three complex flavor neutrino masses. In each texture, we calculate mixing angles and masses, which are consistent with observed data, as well as Majorana CP phases

  13. Age-specific radiation dose commitment factors for a one-year chronic intake

    International Nuclear Information System (INIS)

    Hoenes, G.R.; Soldat, J.K.

    1977-11-01

    During the licensing process for nuclear facilities, radiation doses and dose commitments must be calculated for people in the environs of a nuclear facility. These radiation doses are determined by examining characteristics of population groups, pathways to people, and radionuclides found in those pathways. The pertinent characteristics, which are important in the sense of contributing a significant portion of the total dose, must then be analyzed in depth. Dose factors are generally available for adults, see Reference 1 for example, however numerous improvements in data on decay schemes and half-lives have been made in recent years. In addition, it is advisable to define parameters for calculation of the radiation dose for ages other than adults since the population surrounding nuclear facilities will be composed of various age groups. Further, since infants, children, and teens may have higher rates of intake per unit body mass, it is conceivable that the maximally exposed individual may not be an adult. Thus, it was necessary to develop new radiation-dose commitment factors for various age groups. Dose commitment factors presented in this report have been calculated for a 50-year time period for four age groups

  14. Comparison of changes in the mobility of the pelvic floor muscle on during the abdominal drawing-in maneuver, maximal expiration, and pelvic floor muscle maximal contraction

    OpenAIRE

    Jung, Halim; Jung, Sangwoo; Joo, Sunghee; Song, Changho

    2016-01-01

    [Purpose] The purpose of this study was to compare changes in the mobility of the pelvic floor muscle during the abdominal drawing-in maneuver, maximal expiration, and pelvic floor muscle maximal contraction. [Subjects] Thirty healthy adults participated in this study (15 men and 15 women). [Methods] All participants performed a bridge exercise and abdominal curl-up during the abdominal drawing-in maneuver, maximal expiration, and pelvic floor muscle maximal contraction. Pelvic floor mobility...

  15. LASER APPLICATIONS AND OTHER TOPICS IN QUANTUM ELECTRONICS: Modification of biological objects in water media by CO2-laser radiation

    Science.gov (United States)

    Baranov, G. A.; Belyaev, A. A.; Onikienko, S. B.; Smirnov, S. A.; Khukharev, V. V.

    2005-09-01

    The modification of biological objects (polysaccharides and cells) by CO2-laser radiation in water added drop by drop into the interaction region is studied theoretically and experimentally. Calculations are performed by using the models describing gas-dynamic and heterogeneous processes caused by absorption of laser radiation by water drops. It is found experimentally that the laser modification of polysaccharides leads to the formation of low-molecular derivatives with immunostimulating properties. A dose of the product of laser activation of the yeast culture Saccharamyces cerevisiae prevented the development of a toxic emphysema in mice and protected them against lethal grippe and also prevented a decrease of survival rate, increased the average life, and prevented the development of metabolic and immune disorders in mice exposed to sublethal gamma-radiation doses.

  16. Maximally-localized position, Euclidean path-integral, and thermodynamics in GUP quantum mechanics

    Science.gov (United States)

    Bernardo, Reginald Christian S.; Esguerra, Jose Perico H.

    2018-04-01

    In dealing with quantum mechanics at very high energies, it is essential to adapt to a quasiposition representation using the maximally-localized states because of the generalized uncertainty principle. In this paper, we look at maximally-localized states as eigenstates of the operator ξ = X + iβP that we refer to as the maximally-localized position. We calculate the overlap between maximally-localized states and show that the identity operator can be expressed in terms of the maximally-localized states. Furthermore, we show that the maximally-localized position is diagonal in momentum-space and that the maximally-localized position and its adjoint satisfy commutation and anti-commutation relations reminiscent of the harmonic oscillator commutation and anti-commutation relations. As application, we use the maximally-localized position in developing the Euclidean path-integral and introduce the compact form of the propagator for maximal localization. The free particle momentum-space propagator and the propagator for maximal localization are analytically evaluated up to quadratic-order in β. Finally, we obtain a path-integral expression for the partition function of a thermodynamic system using the maximally-localized states. The partition function of a gas of noninteracting particles is evaluated. At temperatures exceeding the Planck energy, we obtain the gas' maximum internal energy N / 2 β and recover the zero heat capacity of an ideal gas.

  17. Why firms should not always maximize profits

    OpenAIRE

    Kolstad, Ivar

    2006-01-01

    Though corporate social responsibility (CSR) is on the agenda of most major corporations, corporate executives still largely support the view that corporations should maximize the returns to their owners. There are two lines of defence for this position. One is the Friedmanian view that maximizing owner returns is the corporate social responsibility of corporations. The other is a position voiced by many executives, that CSR and profits go together. This paper argues that the first position i...

  18. MAXDOSE-SR: A routine release atmospheric dose model used at SRS

    International Nuclear Information System (INIS)

    Simpkins, A.A.

    2000-01-01

    MAXDOSE-SR is a PC version of the dosimetry code MAXIGASP, which was used to calculate doses to the maximally exposed offsite individual for routine atmospheric releases of radioactive material at the Savannah River Site (SRS). Complete code description, verification of models, and user's manual have been included in this report. Minimal input is required to run the program, and site specific parameters are used when possible

  19. Estimated effects on radiation doses from alternatives in a spent fuel transportation system

    International Nuclear Information System (INIS)

    Schneider, K.J.; Ross, W.A.; Smith, R.I.

    1988-07-01

    This paper contains the results of a study of estimated radiation doses to the public and workers from the transport of spent fuel from commercial nuclear power reactors to a geologic repository. A postulated reference rail/legal-weight truck transportation system is defined that would use current transportation technology, and provide a breakdown of activities and time/distance/dose-rate estimates for each activity within the system. Collective doses are estimated for each of the major activities at the reactor site, in transit, and at the repository receiving facility. Annual individual doses to the maximally exposed individuals or groups of individuals are also estimated. The dose-reduction potentials and costs are estimated for a total of 17 conceptual alternatives and subalternatives to the postulated reference system. Most of the alternatives evaluated are estimated to provide both cost and dose reductions. The major conclusion is that the potential exists for significant future reductions in radiation doses to the public and workers and for reductions in costs compared to those based on a continuation of past practices in the US

  20. Estimated effects on radiation doses from alternatives in a spent fuel transportation system

    International Nuclear Information System (INIS)

    Schneider, K.J.; Ross, W.A.; Smith, R.I.

    1988-01-01

    This paper contains the results of a study of estimated radiation doses to the public and workers from the transport of spent fuel from commercial nuclear power reactors to a geologic repository. A postulated reference rail/legal-weight truck transportation system is defined that would use current transportation technology, and provide a breakdown of activities and time/distance/dose-rate estimates for each activity within the system. Collective doses are estimated for each of the major activities at the reactor site, in transit, and at the repository receiving facility. Annual individual doses to the maximally exposed individuals or groups of individuals also estimated. The dose-reduction potentials and costs are estimated for a total of 17 conceptual alternatives and subalternatives to the postulated reference system. Most of the alternatives evaluated are estimated to provide both cost and dose reductions. The major conclusion is that the potential exists for significant future reductions in radiation doses to the public and workers and for reductions in costs compared to those based on a continuation of past practices in the U.S

  1. Application of a sitting MIRD phantom for effective dose calculations

    International Nuclear Information System (INIS)

    Olsher, R. H.; Van Riper, K. A.

    2005-01-01

    In typical realistic scenarios, dose factors due to 60 Co contaminated steel, used in consumer products, cannot be approximated by standard exposure geometries. It is then necessary to calculate the effective dose using an appropriate anthropomorphic phantom. MCNP calculations were performed using a MIRD human model in two settings. In the first, a male office worker is sitting in a chair containing contaminated steel, surrounded by contaminated furniture. In the second, a male driver is seated inside an automobile, the steel of which is uniformly contaminated. To accurately calculate the dose to lower body organs, especially the gonads, it was essential to modify the MIRD model to simulate two sitting postures: chair and driving position. The phantom modifications are described, and the results of the calculations are presented. In the case of the automobile scenarios, results are compared to those obtained using an isotropic fluence-to-dose conversion function. (authors)

  2. Electron fluence to dose equivalent conversion factors calculated with EGS3 for electrons and positrons with energies from 100 keV to 20 GeV

    International Nuclear Information System (INIS)

    Rogers, D.W.O.

    1983-01-01

    At NRC the general purpose Monte-Carlo electron-photon transport code EGS3 is being applied to a variety of radiation dosimetry problems. To test its accuracy at low energies a detailed set of depth-dose curves for electrons and photons has been generated and compared to previous calculations. It was found that by changing the default step-size algorithm in EGS3, significant changes were obtained for incident electron beam cases. It was found that restricting the step-size to a 4% energy loss was appropriate below incident electron beam energies of 10 MeV. With this change, the calculated depth-dose curves were found to be in reasonable agreement with other calculations right down to incident electron energies of 100 keV although small (less than or equal to 10%) but persistent discrepancies with the NBS code ETRAN were obtained. EGS3 predicts higher initial dose and shorter range than ETRAN. These discrepancies are typical of a wide range of energies as is the better agreement with the results of Nahum. Data is presented for the electron fluence to maximal dose equivalent in a 30 cm thick slab of ICRU 4-element tissue irradiated by broad parallel beams of electrons incident normal to the surface. On their own, these values only give an indication of the dose equivalent expected from a spectrum of electrons since one needs to fold the spectrum maximal dose equivalent value. Calculations have also been done for incident positron beams. Despite the large statistical uncertainties, maximal dose equivalent although their values are 5 to 10% lower in a band around 10 MeV

  3. Maximizing band gaps in plate structures

    DEFF Research Database (Denmark)

    Halkjær, Søren; Sigmund, Ole; Jensen, Jakob Søndergaard

    2006-01-01

    periodic plate using Bloch theory, which conveniently reduces the maximization problem to that of a single base cell. Secondly, we construct a finite periodic plate using a number of the optimized base cells in a postprocessed version. The dynamic properties of the finite plate are investigated......Band gaps, i.e., frequency ranges in which waves cannot propagate, can be found in elastic structures for which there is a certain periodic modulation of the material properties or structure. In this paper, we maximize the band gap size for bending waves in a Mindlin plate. We analyze an infinite...... theoretically and experimentally and the issue of finite size effects is addressed....

  4. Finding Maximal Pairs with Bounded Gap

    DEFF Research Database (Denmark)

    Brodal, Gerth Stølting; Lyngsø, Rune B.; Pedersen, Christian N. S.

    1999-01-01

    . In this paper we present methods for finding all maximal pairs under various constraints on the gap. In a string of length n we can find all maximal pairs with gap in an upper and lower bounded interval in time O(n log n+z) where z is the number of reported pairs. If the upper bound is removed the time reduces...... to O(n+z). Since a tandem repeat is a pair where the gap is zero, our methods can be seen as a generalization of finding tandem repeats. The running time of our methods equals the running time of well known methods for finding tandem repeats....

  5. The key kinematic determinants of undulatory underwater swimming at maximal velocity.

    Science.gov (United States)

    Connaboy, Chris; Naemi, Roozbeh; Brown, Susan; Psycharakis, Stelios; McCabe, Carla; Coleman, Simon; Sanders, Ross

    2016-01-01

    The optimisation of undulatory underwater swimming is highly important in competitive swimming performance. Nineteen kinematic variables were identified from previous research undertaken to assess undulatory underwater swimming performance. The purpose of the present study was to determine which kinematic variables were key to the production of maximal undulatory underwater swimming velocity. Kinematic data at maximal undulatory underwater swimming velocity were collected from 17 skilled swimmers. A series of separate backward-elimination analysis of covariance models was produced with cycle frequency and cycle length as dependent variables (DVs) and participant as a fixed factor, as including cycle frequency and cycle length would explain 100% of the maximal swimming velocity variance. The covariates identified in the cycle-frequency and cycle-length models were used to form the saturated model for maximal swimming velocity. The final parsimonious model identified three covariates (maximal knee joint angular velocity, maximal ankle angular velocity and knee range of movement) as determinants of the variance in maximal swimming velocity (adjusted-r2 = 0.929). However, when participant was removed as a fixed factor there was a large reduction in explained variance (adjusted r2 = 0.397) and only maximal knee joint angular velocity continued to contribute significantly, highlighting its importance to the production of maximal swimming velocity. The reduction in explained variance suggests an emphasis on inter-individual differences in undulatory underwater swimming technique and/or anthropometry. Future research should examine the efficacy of other anthropometric, kinematic and coordination variables to better understand the production of maximal swimming velocity and consider the importance of individual undulatory underwater swimming techniques when interpreting the data.

  6. Kinetic theory in maximal-acceleration invariant phase space

    International Nuclear Information System (INIS)

    Brandt, H.E.

    1989-01-01

    A vanishing directional derivative of a scalar field along particle trajectories in maximal acceleration invariant phase space is identical in form to the ordinary covariant Vlasov equation in curved spacetime in the presence of both gravitational and nongravitational forces. A natural foundation is thereby provided for a covariant kinetic theory of particles in maximal-acceleration invariant phase space. (orig.)

  7. Half-maximal supersymmetry from exceptional field theory

    Energy Technology Data Exchange (ETDEWEB)

    Malek, Emanuel [Arnold Sommerfeld Center for Theoretical Physics, Department fuer Physik, Ludwig-Maximilians-Universitaet Muenchen (Germany)

    2017-10-15

    We study D ≥ 4-dimensional half-maximal flux backgrounds using exceptional field theory. We define the relevant generalised structures and also find the integrability conditions which give warped half-maximal Minkowski{sub D} and AdS{sub D} vacua. We then show how to obtain consistent truncations of type II / 11-dimensional SUGRA which break half the supersymmetry. Such truncations can be defined on backgrounds admitting exceptional generalised SO(d - 1 - N) structures, where d = 11 - D, and N is the number of vector multiplets obtained in the lower-dimensional theory. Our procedure yields the most general embedding tensors satisfying the linear constraint of half-maximal gauged SUGRA. We use this to prove that all D ≥ 4 half-maximal warped AdS{sub D} and Minkowski{sub D} vacua of type II / 11-dimensional SUGRA admit a consistent truncation keeping only the gravitational supermultiplet. We also show to obtain heterotic double field theory from exceptional field theory and comment on the M-theory / heterotic duality. In five dimensions, we find a new SO(5, N) double field theory with a (6 + N)-dimensional extended space. Its section condition has one solution corresponding to 10-dimensional N = 1 supergravity and another yielding six-dimensional N = (2, 0) SUGRA. (copyright 2017 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  8. New generation of nuclear fuels: Stability of different stearates under high doses gamma irradiation in the manufacturing process

    Energy Technology Data Exchange (ETDEWEB)

    Lebeau, D.; Esnouf, S. [Den-Service d’Etude du Comportement des Radionucléides (SECR), CEA, Université Paris-Saclay, F-91191, Gif-sur-Yvette (France); Gracia, J. [Den-Service d' Etudes des Combustibles et Matériaux à base d' Actinides (SECA), CEA, F-30207 Bagnols-sur-Cèze Cedex (France); Audubert, F. [Den-Service d' Analyse et de Caractérisation du Comportement des Combustibles (SA3C), CEA, F- 13115 Saint-Paul-lez-Durance (France); Ferry, M., E-mail: muriel.ferry@cea.fr [Den-Service d’Etude du Comportement des Radionucléides (SECR), CEA, Université Paris-Saclay, F-91191, Gif-sur-Yvette (France)

    2017-07-15

    In the future reactors, the pellets radioactivity will increase due to the modification of the plutonium concentration. The stability of the organic additive used as lubricating/deagglomerating agent has thus to be evaluated. Up to now, zinc stearate is employed, but new additives are tested in this study and compared to zinc stearate. In a first part of this paper, the order of magnitude of the dose deposited in the stearates has been estimated. Afterward, three different stearates have been irradiated, using gamma-rays at doses as high as 2000 kGy. Two atmospheres of irradiation were tested, i.e. inert atmosphere and air. Samples were characterized using the following analytical tools: mass spectrometry, thermogravimetry and infrared spectroscopy. The objective is the evaluation of the ageing of these materials. In the nuclear fuel pellets manufacturing context, the candidate which could replace zinc stearate, if this one is too degraded to fulfill its role of lubricant in the pellets of the future manufacturing, has been determined. - Highlights: •Dose deposition estimation for different stearates. •Stearates radiolysis and radio-oxidization at high doses using gamma-rays. •H{sub 2} emission estimation as a function of atmosphere and dose. •Chemical modifications in stearates as a function of atmosphere and dose. •Comparison of three stearates.

  9. Leucine elicits myotube hypertrophy and enhances maximal contractile force in tissue engineered skeletal muscle in vitro.

    Science.gov (United States)

    Martin, Neil R W; Turner, Mark C; Farrington, Robert; Player, Darren J; Lewis, Mark P

    2017-10-01

    The amino acid leucine is thought to be important for skeletal muscle growth by virtue of its ability to acutely activate mTORC1 and enhance muscle protein synthesis, yet little data exist regarding its impact on skeletal muscle size and its ability to produce force. We utilized a tissue engineering approach in order to test whether supplementing culture medium with leucine could enhance mTORC1 signaling, myotube growth, and muscle function. Phosphorylation of the mTORC1 target proteins 4EBP-1 and rpS6 and myotube hypertrophy appeared to occur in a dose dependent manner, with 5 and 20 mM of leucine inducing similar effects, which were greater than those seen with 1 mM. Maximal contractile force was also elevated with leucine supplementation; however, although this did not appear to be enhanced with increasing leucine doses, this effect was completely ablated by co-incubation with the mTOR inhibitor rapamycin, showing that the augmented force production in the presence of leucine was mTOR sensitive. Finally, by using electrical stimulation to induce chronic (24 hr) contraction of engineered skeletal muscle constructs, we were able to show that the effects of leucine and muscle contraction are additive, since the two stimuli had cumulative effects on maximal contractile force production. These results extend our current knowledge of the efficacy of leucine as an anabolic nutritional aid showing for the first time that leucine supplementation may augment skeletal muscle functional capacity, and furthermore validates the use of engineered skeletal muscle for highly-controlled investigations into nutritional regulation of muscle physiology. © 2017 The Authors. Journal of Cellular Physiology Published by wiley periodicals, Inc.

  10. The effects of size and surface modification of amorphous silica particles on biodistribution and liver metabolism in mice

    International Nuclear Information System (INIS)

    Lu, Xiaoyan; Ji, Cai; Jin, Tingting; Fan, Xiaohui

    2015-01-01

    Engineered nanoparticles, with unconventional properties, are promising platforms for biomedical applications. Since they may interact with a wide variety of biomolecules, it is critical to understand the impact of the physicochemical properties of engineered nanoparticles on biological systems. In this study, the effects of particle size and surface modification alone or in combination of amorphous silica particles (SPs) on biological responses were determined using a suite of general toxicological assessments and metabonomics analysis in mice model. Our results suggested that amino or carboxyl surface modification mitigated the liver toxicity of plain-surface SPs. 30 nm SPs with amino surface modification were found to be the most toxic SPs among all the surface-modified SP treatments at the same dosage. When treatment dose was increased, submicro-sized SPs with amino or carboxyl surface modification also induced liver toxicity. Biodistribution studies suggested that 70 nm SPs were mainly accumulated in liver and spleen regardless of surface modifications. Interestingly, these two organs exhibited different uptake trends. Furthermore, metabonomics studies indicated that surface modification plays a more dominant role to affect the liver metabolism than particle size. (paper)

  11. Maximal slicing of D-dimensional spherically symmetric vacuum spacetime

    International Nuclear Information System (INIS)

    Nakao, Ken-ichi; Abe, Hiroyuki; Yoshino, Hirotaka; Shibata, Masaru

    2009-01-01

    We study the foliation of a D-dimensional spherically symmetric black-hole spacetime with D≥5 by two kinds of one-parameter families of maximal hypersurfaces: a reflection-symmetric foliation with respect to the wormhole slot and a stationary foliation that has an infinitely long trumpetlike shape. As in the four-dimensional case, the foliations by the maximal hypersurfaces avoid the singularity irrespective of the dimensionality. This indicates that the maximal slicing condition will be useful for simulating higher-dimensional black-hole spacetimes in numerical relativity. For the case of D=5, we present analytic solutions of the intrinsic metric, the extrinsic curvature, the lapse function, and the shift vector for the foliation by the stationary maximal hypersurfaces. These data will be useful for checking five-dimensional numerical-relativity codes based on the moving puncture approach.

  12. Modification of graphite structure by irradiation, revealed by thermal oxidation. Examination by electronic microscopy

    International Nuclear Information System (INIS)

    Rouaud, Michel

    1969-01-01

    Based on the analysis of images obtained by electronic microscopy, this document reports the comparative study of the action of neutrons on three different graphites: a natural one (Ticonderoga) and two pyrolytic ones (Carbone-Lorraine and Raytheon). The approach is based on the modification of features of thermal oxidation of graphites by dry air after irradiation. Different corrosion features are identified. The author states that there seems to be a relationship between the number and shape of these features, and defects existing on the irradiated graphite before oxidation. For low doses, the feature aspect varies with depth at which oxidation occurs. For higher doses, the aspect remains the same [fr

  13. Left ventricle expands maximally preceding end-diastole. Radionuclide ventriculography study

    International Nuclear Information System (INIS)

    Horinouchi, Osamu

    2002-01-01

    It has been considered that left ventricle (LV) expands maximally at the end-diastole. However, is it exactly coincident with this point? This study was aimed to determine whether the maximal expansion of LV coincides with the peak of R wave on electrocardiogram. Thirty-three angina pectoris patients with normal LV motion were examined using radionuclide ventriculography. Data were obtained from every 30 ms backward frame from the peak of R wave. All patients showed the time of maximal expansion preceded the peak of R wave. The intervals from the peak of R wave and the onset of P wave to maximal expansion of LV was 105±29 ms and 88±25 ms, respectively. This period corresponds to the timing of maximal excurtion of mitral valve by atrial contraction, and the centripetal motion of LV without losing its volume before end-diastole may be interpreted on account of the movement of mitral valve toward closure. These findings suggest that LV expands maximally between P and R wave after atrial contraction, preceding the peak of R wave thought conventionally as the end-diastole. (author)

  14. Benchmark measurements and simulations of dose perturbations due to metallic spheres in proton beams

    International Nuclear Information System (INIS)

    Newhauser, Wayne D.; Rechner, Laura; Mirkovic, Dragan; Yepes, Pablo; Koch, Nicholas C.; Titt, Uwe; Fontenot, Jonas D.; Zhang, Rui

    2013-01-01

    Monte Carlo simulations are increasingly used for dose calculations in proton therapy due to its inherent accuracy. However, dosimetric deviations have been found using Monte Carlo code when high density materials are present in the proton beamline. The purpose of this work was to quantify the magnitude of dose perturbation caused by metal objects. We did this by comparing measurements and Monte Carlo predictions of dose perturbations caused by the presence of small metal spheres in several clinical proton therapy beams as functions of proton beam range and drift space. Monte Carlo codes MCNPX, GEANT4 and Fast Dose Calculator (FDC) were used. Generally good agreement was found between measurements and Monte Carlo predictions, with the average difference within 5% and maximum difference within 17%. The modification of multiple Coulomb scattering model in MCNPX code yielded improvement in accuracy and provided the best overall agreement with measurements. Our results confirmed that Monte Carlo codes are well suited for predicting multiple Coulomb scattering in proton therapy beams when short drift spaces are involved. - Highlights: • We compared measurements and Monte Carlo predictions of dose perturbations caused by the metal objects in proton beams. • Different Monte Carlo codes were used, including MCNPX, GEANT4 and Fast Dose Calculator. • Good agreement was found between measurements and Monte Carlo simulations. • The modification of multiple Coulomb scattering model in MCNPX code yielded improved accuracy. • Our results confirmed that Monte Carlo codes are well suited for predicting multiple Coulomb scattering in proton therapy

  15. Results of the Phase I Dose-Escalating Study of Motexafin Gadolinium With Standard Radiotherapy in Patients With Glioblastoma Multiforme

    International Nuclear Information System (INIS)

    Ford, Judith M.; Seiferheld, Wendy; Alger, Jeffrey R.; Wu, Genevieve; Endicott, Thyra J.; Mehta, Minesh; Curran, Walter; Phan, See-Chun

    2007-01-01

    Purpose: Motexafin gadolinium (MGd) is a putative radiation enhancer initially evaluated in patients with brain metastases. This Phase I trial studied the safety and tolerability of a 2-6-week course (10-22 doses) of MGd with radiotherapy for glioblastoma multiforme. Methods and Materials: A total of 33 glioblastoma multiforme patients received one of seven MGd regimens starting at 10 doses of 4 mg/kg/d MGd and escalating to 22 doses of 5.3 mg/kg/d MGd (5 or 10 daily doses then three times per week). The National Cancer Institute Cancer Therapy Evaluation Program toxicity and stopping rules were applied. Results: The maximal tolerated dose was 5.0 mg/kg/d MGd (5 d/wk for 2 weeks, then three times per week) for 22 doses. The dose-limiting toxicity was reversible transaminase elevation. Adverse reactions included rash/pruritus (45%), chills/fever (30%), and self-limiting vesiculobullous rash of the thumb and fingers (42%). The median survival of 17.6 months prompted a case-matched analysis. In the case-matched analysis, the MGd patients had a median survival of 16.1 months (n = 31) compared with the matched Radiation Therapy Oncology Group database patients with a median survival of 11.8 months (hazard ratio, 0.43; 95% confidence interval, 0.20-0.94). Conclusion: The maximal tolerated dose of MGd with radiotherapy for glioblastoma multiforme in this study was 5 mg/kg/d for 22 doses (daily for 2 weeks, then three times weekly). The baseline survival calculations suggest progression to Phase II trials is appropriate, with the addition of MGd to radiotherapy with concurrent and adjuvant temozolomide

  16. Maximization of regional probabilities using Optimal Surface Graphs

    DEFF Research Database (Denmark)

    Arias Lorza, Andres M.; Van Engelen, Arna; Petersen, Jens

    2018-01-01

    Purpose: We present a segmentation method that maximizes regional probabilities enclosed by coupled surfaces using an Optimal Surface Graph (OSG) cut approach. This OSG cut determines the globally optimal solution given a graph constructed around an initial surface. While most methods for vessel...... wall segmentation only use edge information, we show that maximizing regional probabilities using an OSG improves the segmentation results. We applied this to automatically segment the vessel wall of the carotid artery in magnetic resonance images. Methods: First, voxel-wise regional probability maps...... were obtained using a Support Vector Machine classifier trained on local image features. Then, the OSG segments the regions which maximizes the regional probabilities considering smoothness and topological constraints. Results: The method was evaluated on 49 carotid arteries from 30 subjects...

  17. Effects of low dose radiation and epigenetic regulation

    International Nuclear Information System (INIS)

    Jiao Benzheng; Ma Shumei; Yi Heqing; Kong Dejuan; Zhao Guangtong; Gao Lin; Liu Xiaodong

    2010-01-01

    Purpose: To conclude the relationship between epigenetics regulation and radiation responses, especially in low-dose area. Methods: The literature was examined for papers related to the topics of DNA methylation, histone modifications, chromatin remodeling and non-coding RNA modulation in low-dose radiation responses. Results: DNA methylation and radiation can regulate reciprocally, especially in low-dose radiation responses. The relationship between histone methylation and radiation mainly exists in the high-dose radiation area; histone deacetylase (HDAC) inhibitors show a promising application to enhance radiation sensitivity, no matter whether in low-dose or high-dose areas; the connection between γ-H2AX and LDR has been remained unknown, although γ-H2AX has been shown no radiation sensitivities with 1-15 Gy irradiation; histone ubiquitination play an important role in DNA damage repair mechanism. Moreover, chromatin remodeling has an integral role in DSB repair and the chromatin response, in general, may be precede DNA end resection. Finally, the effect of radiation on miRNA expression seems to vary according to cell type, radiation dose, and post-irradiation time point. Conclusion: Although the advance of epigenetic regulation on radiation responses, which we are managing to elucidate in this review, has been concluded, there are many questions and blind blots deserved to investigated, especially in low-dose radiation area. However, as progress on epigenetics, we believe that many new elements will be identified in the low-dose radiation responses which may put new sights into the mechanisms of radiation responses and radiotherapy. (authors)

  18. Singularity Structure of Maximally Supersymmetric Scattering Amplitudes

    DEFF Research Database (Denmark)

    Arkani-Hamed, Nima; Bourjaily, Jacob L.; Cachazo, Freddy

    2014-01-01

    We present evidence that loop amplitudes in maximally supersymmetric (N=4) Yang-Mills theory (SYM) beyond the planar limit share some of the remarkable structures of the planar theory. In particular, we show that through two loops, the four-particle amplitude in full N=4 SYM has only logarithmic ...... singularities and is free of any poles at infinity—properties closely related to uniform transcendentality and the UV finiteness of the theory. We also briefly comment on implications for maximal (N=8) supergravity theory (SUGRA)....

  19. Identities on maximal subgroups of GLn(D)

    International Nuclear Information System (INIS)

    Kiani, D.; Mahdavi-Hezavehi, M.

    2002-04-01

    Let D be a division ring with centre F. Assume that M is a maximal subgroup of GL n (D), n≥1 such that Z(M) is algebraic over F. Group identities on M and polynomial identities on the F-linear hull F[M] are investigated. It is shown that if F[M] is a PI-algebra, then [D:F] n (D) and M is a maximal subgroup of N. If M satisfies a group identity, it is shown that M is abelian-by-finite. (author)

  20. Adaptive maximal poisson-disk sampling on surfaces

    KAUST Repository

    Yan, Dongming

    2012-01-01

    In this paper, we study the generation of maximal Poisson-disk sets with varying radii on surfaces. Based on the concepts of power diagram and regular triangulation, we present a geometric analysis of gaps in such disk sets on surfaces, which is the key ingredient of the adaptive maximal Poisson-disk sampling framework. Moreover, we adapt the presented sampling framework for remeshing applications. Several novel and efficient operators are developed for improving the sampling/meshing quality over the state-of-theart. © 2012 ACM.

  1. Dose-response relationship in the treatment of gastrointestinal disorders.

    Science.gov (United States)

    Weihrauch, T R; Demol, P

    1989-08-01

    Numerous clinical studies have been performed to establish efficacy and safety of drugs in gastroenterological disorders. Only in a few if any of these studies, however, the rationale for the optimal dose and the dose regimens, respectively, have been addressed. Adequate and well-controlled dose finding studies play a key role in the clinical assessment of new drugs and in the evaluation of new indications. Hereby the range from the minimal effective dose to the maximal effective and well tolerated dose can be assessed and thus the optimal dose-range and dosage regimen be determined. Meaningful pharmacodynamic studies can be performed in the gastrointestinal tract also in healthy volunteers provided that a method with a high predictability for the desired therapeutic effect is available such as measurement of gastric acid secretion and its inhibition by a drug. Dose finding studies in gastroenterology can be carried out under two main aspects: First, to assess the pharmacodynamic and therapeutic effect of a compound on the gastrointestinal tract (e.g. anti-ulcer drug). Second, to evaluate the side effects of a drug on the gastrointestinal tract (e.g. gastric mucosal damage by non-steroidal anti-inflammatory drugs). For the evaluation of new drugs in gastrointestinal therapy a number of methods are available which yield accurate and reproducible data. While careful clinical-pharmacological dose-response studies using these methods have been carried out already more than a decade ago, it is surprising that therapeutic dose finding studies have become available only during the past few years. For scientific as well as for ethical reasons more trials which determine the optimal therapeutic dose are warranted.

  2. Ultraviolet radiation therapy and UVR dose models

    Energy Technology Data Exchange (ETDEWEB)

    Grimes, David Robert, E-mail: davidrobert.grimes@oncology.ox.ac.uk [School of Physical Sciences, Dublin City University, Glasnevin, Dublin 9, Ireland and Cancer Research UK/MRC Oxford Institute for Radiation Oncology, Gray Laboratory, University of Oxford, Old Road Campus Research Building, Oxford OX3 7DQ (United Kingdom)

    2015-01-15

    Ultraviolet radiation (UVR) has been an effective treatment for a number of chronic skin disorders, and its ability to alleviate these conditions has been well documented. Although nonionizing, exposure to ultraviolet (UV) radiation is still damaging to deoxyribonucleic acid integrity, and has a number of unpleasant side effects ranging from erythema (sunburn) to carcinogenesis. As the conditions treated with this therapy tend to be chronic, exposures are repeated and can be high, increasing the lifetime probability of an adverse event or mutagenic effect. Despite the potential detrimental effects, quantitative ultraviolet dosimetry for phototherapy is an underdeveloped area and better dosimetry would allow clinicians to maximize biological effect whilst minimizing the repercussions of overexposure. This review gives a history and insight into the current state of UVR phototherapy, including an overview of biological effects of UVR, a discussion of UVR production, illness treated by this modality, cabin design and the clinical implementation of phototherapy, as well as clinical dose estimation techniques. Several dose models for ultraviolet phototherapy are also examined, and the need for an accurate computational dose estimation method in ultraviolet phototherapy is discussed.

  3. Ultraviolet radiation therapy and UVR dose models

    International Nuclear Information System (INIS)

    Grimes, David Robert

    2015-01-01

    Ultraviolet radiation (UVR) has been an effective treatment for a number of chronic skin disorders, and its ability to alleviate these conditions has been well documented. Although nonionizing, exposure to ultraviolet (UV) radiation is still damaging to deoxyribonucleic acid integrity, and has a number of unpleasant side effects ranging from erythema (sunburn) to carcinogenesis. As the conditions treated with this therapy tend to be chronic, exposures are repeated and can be high, increasing the lifetime probability of an adverse event or mutagenic effect. Despite the potential detrimental effects, quantitative ultraviolet dosimetry for phototherapy is an underdeveloped area and better dosimetry would allow clinicians to maximize biological effect whilst minimizing the repercussions of overexposure. This review gives a history and insight into the current state of UVR phototherapy, including an overview of biological effects of UVR, a discussion of UVR production, illness treated by this modality, cabin design and the clinical implementation of phototherapy, as well as clinical dose estimation techniques. Several dose models for ultraviolet phototherapy are also examined, and the need for an accurate computational dose estimation method in ultraviolet phototherapy is discussed

  4. Gamma-ray effect on sweet potato

    International Nuclear Information System (INIS)

    Ferdes, O.; Ciofu, R.; Stroia, L.; Ghering, A.; Ferdes, M.

    1994-01-01

    The paper presents the results on modification occurred in biochemical properties of sweet potato (Ipomea batatus L.) after gamma irradiation. Two varieties, named Victoria Ianb (a white variety) and Portocaliu (a red variety), were selected and acclimatized for the agrometeorological conditions of Romania. The samples consist of roots from both usual and experimental crops. They were irradiated in batch, one week after harvesting, with a ICPR Co-60 gamma-ray source by approx. 370 TBq, dose range 100-500 Gy, dose rate 100±5 Gy/hour, dose uniformity ±5%, temperature 10 o C, 80±5% relative humidity (rh). The irradiation doses received were checked using the Fricke ferrous sulphate dosimeter procedure. The roots were kept two months at relative darkness, 6-11 o C, 60-75% rh and analyzed from time to time (initial, 5, 7, 14, 30 and 60 days). The following parameters are analyzed by conventional methods: total and reducing sugars (in De equivalent, %, on dry weight basis), starch content and the activities of sugar metabolizing enzymes. The red variety had a better behaviour towards irradiation that the white one. The sugar contents (both total and reducing), as well as starch, varied more in the white variety. The sugar metabolizing enzyme activities were influenced by both irradiation and storage conditions. Their activities were maximal at 200 and 300 Gy, and decreased significantly at higher doses. The activities also decreased in time, their variations being higher at lower doses (100 and 200 Gy). The results showed no significant influence of gamma irradiation on storage life. The modifications induced in sugar contents and enzyme activities had maximal effects at 200-300 Gy. (author)

  5. Is the β phase maximal?

    International Nuclear Information System (INIS)

    Ferrandis, Javier

    2005-01-01

    The current experimental determination of the absolute values of the CKM elements indicates that 2 vertical bar V ub /V cb V us vertical bar =(1-z), with z given by z=0.19+/-0.14. This fact implies that irrespective of the form of the quark Yukawa matrices, the measured value of the SM CP phase β is approximately the maximum allowed by the measured absolute values of the CKM elements. This is β=(π/6-z/3) for γ=(π/3+z/3), which implies α=π/2. Alternatively, assuming that β is exactly maximal and using the experimental measurement sin(2β)=0.726+/-0.037, the phase γ is predicted to be γ=(π/2-β)=66.3 o +/-1.7 o . The maximality of β, if confirmed by near-future experiments, may give us some clues as to the origin of CP violation

  6. A New Augmentation Based Algorithm for Extracting Maximal Chordal Subgraphs.

    Science.gov (United States)

    Bhowmick, Sanjukta; Chen, Tzu-Yi; Halappanavar, Mahantesh

    2015-02-01

    A graph is chordal if every cycle of length greater than three contains an edge between non-adjacent vertices. Chordal graphs are of interest both theoretically, since they admit polynomial time solutions to a range of NP-hard graph problems, and practically, since they arise in many applications including sparse linear algebra, computer vision, and computational biology. A maximal chordal subgraph is a chordal subgraph that is not a proper subgraph of any other chordal subgraph. Existing algorithms for computing maximal chordal subgraphs depend on dynamically ordering the vertices, which is an inherently sequential process and therefore limits the algorithms' parallelizability. In this paper we explore techniques to develop a scalable parallel algorithm for extracting a maximal chordal subgraph. We demonstrate that an earlier attempt at developing a parallel algorithm may induce a non-optimal vertex ordering and is therefore not guaranteed to terminate with a maximal chordal subgraph. We then give a new algorithm that first computes and then repeatedly augments a spanning chordal subgraph. After proving that the algorithm terminates with a maximal chordal subgraph, we then demonstrate that this algorithm is more amenable to parallelization and that the parallel version also terminates with a maximal chordal subgraph. That said, the complexity of the new algorithm is higher than that of the previous parallel algorithm, although the earlier algorithm computes a chordal subgraph which is not guaranteed to be maximal. We experimented with our augmentation-based algorithm on both synthetic and real-world graphs. We provide scalability results and also explore the effect of different choices for the initial spanning chordal subgraph on both the running time and on the number of edges in the maximal chordal subgraph.

  7. An effective dose of ketamine for eliminating pain during injection of propofol: a dose response study.

    Science.gov (United States)

    Wang, M; Wang, Q; Yu, Y Y; Wang, W S

    2013-09-01

    Ketamine can completely eliminate pain associated with propofol injection. However, the effective dose of ketamine to eliminate propofol injection pain has not been determined. The purpose of this study was to determine the effective dose of ketamine needed to eliminate pain in 50% and 95% of patients (ED50 and ED95, respectively) during propofol injections. This study was conducted in a double-blinded fashion and included 50 patients scheduled for elective gynecological laparoscopy under general anesthesia. The initial dose of ketamine used in the first patient was 0.25mg/kg. The dosing modifications were in increments or decrements of 0.025 mg/kg. Ketamine was administered 15 seconds before injecting propofol (2.5mg/kg), which was injected at a rate of 1mL/s. Patients were asked to rate their pain during propofol injection every 5s econds using a 0-3 pain scale. The highest pain score was recorded. The ED50, ED95 and 95% confidence intervals (CI) were determined by probit analyses. The dose of ketamine ranged from 0.175 to 0.275 mg/kg. The ED50 and ED95 of ketamine for eliminating pain during propofol injection were 0.227 mg/kg and 0.283 mg/kg, respectively (95%CI: 0.211-0.243 mg/kg and 0.26-0.364 mg/kg, respectively). Ketamine at an approximate dose of 0.3mg/kg was effective in eliminating pain during propofol injection. Copyright © 2013 Société française d’anesthésie et de réanimation (Sfar). Published by Elsevier SAS. All rights reserved.

  8. Assessment of protein modifications in liver of rats under chronic treatment with paracetamol (acetaminophen) using two complementary mass spectrometry-based metabolomic approaches.

    Science.gov (United States)

    Mast, Carole; Lyan, Bernard; Joly, Charlotte; Centeno, Delphine; Giacomoni, Franck; Martin, Jean-François; Mosoni, Laurent; Dardevet, Dominique; Pujos-Guillot, Estelle; Papet, Isabelle

    2015-04-29

    Liver protein can be altered under paracetamol (APAP) treatment. APAP-protein adducts and other protein modifications (oxidation/nitration, expression) play a role in hepatotoxicity induced by acute overdoses, but it is unknown whether liver protein modifications occur during long-term treatment with non-toxic doses of APAP. We quantified APAP-protein adducts and assessed other protein modifications in the liver from rats under chronic (17 days) treatment with two APAP doses (0.5% or 1% of APAP in the diet w/w). A targeted metabolomic method was validated and used to quantify APAP-protein adducts as APAP-cysteine adducts following proteolytic hydrolysis. The limit of detection was found to be 7ng APAP-cysteine/mL hydrolysate i.e. an APAP-Cys to tyrosine ratio of 0.016‰. Other protein modifications were assessed on the same protein hydrolysate by untargeted metabolomics including a new strategy to process the data and identify discriminant molecules. These two complementary mass spectrometry (MS)-based metabolic approaches enabled the assessment of a wide range of protein modifications induced by chronic treatment with APAP. APAP-protein adducts were detected even in the absence of glutathione depletion and hepatotoxicity, i.e. in the 0.5% APAP group, and increased by 218% in the 1% APAP group compared to the 0.5% APAP group. At the same time, the untargeted metabolomic method revealed a decrease in the binding of cysteine, cysteinyl-glycine and GSH to thiol groups of protein cysteine residues, an increase in the oxidation of tryptophan and proline residues and a modification in protein expression. This wide range of modifications in liver proteins occurred in rats under chronic treatment with APAP that did not induce hepatotoxicity. Copyright © 2015 Elsevier B.V. All rights reserved.

  9. Robust EM Continual Reassessment Method in Oncology Dose Finding

    Science.gov (United States)

    Yuan, Ying; Yin, Guosheng

    2012-01-01

    The continual reassessment method (CRM) is a commonly used dose-finding design for phase I clinical trials. Practical applications of this method have been restricted by two limitations: (1) the requirement that the toxicity outcome needs to be observed shortly after the initiation of the treatment; and (2) the potential sensitivity to the prespecified toxicity probability at each dose. To overcome these limitations, we naturally treat the unobserved toxicity outcomes as missing data, and use the expectation-maximization (EM) algorithm to estimate the dose toxicity probabilities based on the incomplete data to direct dose assignment. To enhance the robustness of the design, we propose prespecifying multiple sets of toxicity probabilities, each set corresponding to an individual CRM model. We carry out these multiple CRMs in parallel, across which model selection and model averaging procedures are used to make more robust inference. We evaluate the operating characteristics of the proposed robust EM-CRM designs through simulation studies and show that the proposed methods satisfactorily resolve both limitations of the CRM. Besides improving the MTD selection percentage, the new designs dramatically shorten the duration of the trial, and are robust to the prespecification of the toxicity probabilities. PMID:22375092

  10. The third generation multi-purpose plasma immersion ion implanter for surface modification of materials

    CERN Document Server

    Tang Bao Yin; Wang Xiao Feng; Gan Kong Yin; Wang Song Yan; Chu, P K; Huang Nian Ning; Sun Hong

    2002-01-01

    The third generation multi-purpose plasma immersion ion implantation (PIII) equipment has been successfully used for research and development of surface modification of biomedical materials, metals and their alloys in the Southwest Jiaotong University. The implanter equipped with intense current, pulsed cathodic arc metal plasma sources which have both strong coating function and gas and metal ion implantation function. Its pulse high voltage power supply can provide big output current. It can acquire very good implantation dose uniformity. The equipment can both perform ion implantation and combine ion implantation with sputtering deposition and coating to form many kinds of synthetic surface modification techniques. The main design principles, features of important components and achievement of research works in recent time have been described

  11. Image quality and dose assessment in digital breast tomosynthesis: A Monte Carlo study

    International Nuclear Information System (INIS)

    Baptista, M.; Di Maria, S.; Oliveira, N.; Matela, N.; Janeiro, L.; Almeida, P.; Vaz, P.

    2014-01-01

    Mammography is considered a standard technique for the early detection of breast cancer. However, its sensitivity is limited essentially due to the issue of the overlapping breast tissue. This limitation can be partially overcome, with a relatively new technique, called digital breast tomosynthesis (DBT). For this technique, optimization of acquisition parameters which maximize image quality, whilst complying with the ALARA principle, continues to be an area of considerable research. The aim of this work was to study the best quantum energies that optimize the image quality with the lowest achievable dose in DBT and compare these results with the digital mammography (DM) ones. Monte Carlo simulations were performed using the state-of-the-art computer program MCNPX 2.7.0 in order to generate several 2D cranio-caudal (CC) projections obtained during an acquisition of a standard DBT examination. Moreover, glandular absorbed doses and photon flux calculations, for each projection image, were performed. A homogeneous breast computational phantom with 50%/50% glandular/adipose tissue composition was used and two compressed breast thicknesses were evaluated: 4 cm and 8 cm. The simulated projection images were afterwards reconstructed with an algebraic reconstruction tool and the signal difference to noise ratio (SDNR) was calculated in order to evaluate the image quality in DBT and DM. Finally, a thorough comparison between the results obtained in terms of SDNR and dose assessment in DBT and DM was performed. - Highlights: • Optimization of the image quality in digital breast tomosynthesis. • Calculation of photon energies that maximize the signal difference to noise ratio. • Projections images and dose calculations through the Monte Carlo (MC) method. • Tumor masses and microcalcifications included in the MC model. • A dose saving of about 30% can be reached if optimal photon energies are used

  12. Quantum speedup in solving the maximal-clique problem

    Science.gov (United States)

    Chang, Weng-Long; Yu, Qi; Li, Zhaokai; Chen, Jiahui; Peng, Xinhua; Feng, Mang

    2018-03-01

    The maximal-clique problem, to find the maximally sized clique in a given graph, is classically an NP-complete computational problem, which has potential applications ranging from electrical engineering, computational chemistry, and bioinformatics to social networks. Here we develop a quantum algorithm to solve the maximal-clique problem for any graph G with n vertices with quadratic speedup over its classical counterparts, where the time and spatial complexities are reduced to, respectively, O (√{2n}) and O (n2) . With respect to oracle-related quantum algorithms for the NP-complete problems, we identify our algorithm as optimal. To justify the feasibility of the proposed quantum algorithm, we successfully solve a typical clique problem for a graph G with two vertices and one edge by carrying out a nuclear magnetic resonance experiment involving four qubits.

  13. Reconstruction of erythemal UV-doses for two stations in Austria: a comparison between alpine and urban regions

    Directory of Open Access Journals (Sweden)

    H. E. Rieder

    2008-10-01

    Full Text Available The aim of this study is the reconstruction of past UV-doses for two stations in Austria, Hoher Sonnblick and Vienna, using a physical radiation transfer model. The method uses the modeled UV-dose under clear-sky conditions, cloud modification factors and a correction factor as input variables. To identify the influence of temporal resolution of input data and modification factors, an ensemble of four different modelling approaches was calculated, each with hourly or daily resolution. This is especially important because we found no other study describing the influence of the temporal resolution of input data on model performance. Following the results of the statistical analysis of the evaluation period the model with the highest temporal resolution (HMC was chosen for the reconstruction of UV-doses. A good agreement between modelled and measured values of erythemally effective UV-doses was found at both stations. In relation to the reference period 1976–1985 an increase in the erythemal UV-dose in Vienna of 11% is visible in the period 1986–1995 and an increase of 17% in the period 1996–2005 can be seen. At Hoher Sonnblick the corresponding increase is 2% and 9%. For the different seasons the strongest increase in erythemal UV-dose has been found for winter and spring season at both stations. Further the influences of total ozone and cloudiness on changes in erythemal UV-doses were analyzed. This analysis showed for both stations, that changes in total ozone had a larger influence on erythemal UV-doses than changes in cloudiness.

  14. Mathematical modelling for dose deposition in photon-therapy

    International Nuclear Information System (INIS)

    Pichard, Teddy

    2016-01-01

    Radiotherapy treatments consists in irradiating the patient with beams of energetic particles (typically photons) targeting the tumor. Such particles are transported through the medium and deposit energy in the medium. This deposited energy is the so called dose, responsible for the biological effect of the radiations. The present work aim to develop numerical methods for dose computation and optimization that are competitive in terms of computational cost and accuracy compared to reference method. The motion of particles is first studied through a system of linear transport equations at the kinetic level. However, solving directly such systems is numerically too costly for medical application. Instead, the moment method is used with a special focus on the Mn models. Those moment equations are non-linear and valid under a condition called realizability. Standard numerical schemes for moment equations are constrained by stability conditions which happen to be very restrictive when the medium contains low density regions. Inconditionally stable numerical schemes adapted to moment equations (preserving the realizability property) are developed. Those schemes are shown to be competitive in terms of computational costs compared to reference approaches. Finally they are applied to in an optimization procedure aiming to maximize the dose in the tumor and to minimize the dose in healthy tissues. (author) [fr

  15. Bioactivity-guided fractionation of an antidiarrheal Chinese herb Rhodiola kirilowii (Regel) Maxim reveals (-)-epicatechin-3-gallate and (-)-epigallocatechin-3-gallate as inhibitors of cystic fibrosis transmembrane conductance regulator.

    Science.gov (United States)

    Chen, Lei; Yu, Bo; Zhang, Yaofang; Gao, Xin; Zhu, Liang; Ma, Tonghui; Yang, Hong

    2015-01-01

    Cystic fibrosis transmembrane conductance regulator (CFTR) is the principal apical route for transepithelial fluid transport induced by enterotoxin. Inhibition of CFTR has been confirmed as a pharmaceutical approach for the treatment of secretory diarrhea. Many traditional Chinese herbal medicines, like Rhodiola kirilowii (Regel) Maxim, have long been used for the treatment of secretory diarrhea. However, the active ingredients responsible for their therapeutic effectiveness remain unknown. The purpose of this study is to identify CFTR inhibitors from Rhodiola kirilowii (Regel) Maxim via bioactivity-directed isolation strategy. We first identified fractions of Rhodiola kirilowii (Regel) Maxim that inhibited CFTR Cl- channel activity. Further bioactivity-directed fractionation led to the identification of (-)-epigallocatechin-3-gallate (EGCG) as CFTR Cl- channel inhibitor. Analysis of 5 commercially available EGCG analogs including (+)-catechins (C), (-)-epicatechin (EC), (-)-epigallocatechin (EGC), (-)-epicatechin-3-gallate (ECG) and EGCG revealed that ECG also had CFTR inhibitory activity. EGCG dose-dependently and reversibly inhibited CFTR Cl- channel activity in transfected FRT cells with an IC50 value around 100 μM. In ex vivo studies, EGCG and ECG inhibited CFTR-mediated short-circuit currents in isolated rat colonic mucosa in a dose-dependent manner. In an intestinal closed-loop model in mice, intraluminal application of EGCG (10 μg) and ECG (10 μg) significantly reduced cholera toxin-induced intestinal fluid secretion. CFTR Cl- channel is a molecular target of natural compounds EGCG and ECG. CFTR inhibition may account, at least in part, for the antidiarrheal activity of Rhodiola kirilowii (Regel) Maxim. EGCG and ECG could be new lead compounds for development of CFTR-related diseases such as secretory diarrhea.

  16. Muscle mitochondrial capacity exceeds maximal oxygen delivery in humans

    DEFF Research Database (Denmark)

    Boushel, Robert Christopher; Gnaiger, Erich; Calbet, Jose A L

    2011-01-01

    Across a wide range of species and body mass a close matching exists between maximal conductive oxygen delivery and mitochondrial respiratory rate. In this study we investigated in humans how closely in-vivo maximal oxygen consumption (VO(2) max) is matched to state 3 muscle mitochondrial respira...

  17. Reduction of the secondary neutron dose in passively scattered proton radiotherapy, using an optimized pre-collimator/collimator

    International Nuclear Information System (INIS)

    Brenner, David J; Elliston, Carl D; Hall, Eric J; Paganetti, Harald

    2009-01-01

    Proton radiotherapy represents a potential major advance in cancer therapy. Most current proton beams are spread out to cover the tumor using passive scattering and collimation, resulting in an extra whole-body high-energy neutron dose, primarily from proton interactions with the final collimator. There is considerable uncertainty as to the carcinogenic potential of low doses of high-energy neutrons, and thus we investigate whether this neutron dose can be significantly reduced without major modifications to passively scattered proton beam lines. Our goal is to optimize the design features of a patient-specific collimator or pre-collimator/collimator assembly. There are a number of often contradictory design features, in terms of geometry and material, involved in an optimal design. For example, plastic or hybrid plastic/metal collimators have a number of advantages. We quantify these design issues, and investigate the practical balances that can be achieved to significantly reduce the neutron dose without major alterations to the beamline design or function. Given that the majority of proton therapy treatments, at least for the next few years, will use passive scattering techniques, reducing the associated neutron-related risks by simple modifications of the collimator assembly design is a desirable goal.

  18. Non-linear dose response of a few plant taxa to acute gamma radiation

    International Nuclear Information System (INIS)

    George, J.T.; Patel, B.B.; Pius, J.; Narula, B.; Shankhadarwar, S.; Rane, V.A.; Venu-Babu, P.; Eapen, S.; Singhal, R.K.

    2014-01-01

    Micronuclei induction serves as an essential biomarker of radiation stress in a living system, and the simplicity of its detection technique has made it a widely used indicator of radiation damage. The present study was conducted to reveal the cytological dose-response of a few plant taxa, viz., Allium cepa var. aggregatum Linn., Allium sativum Linn., Chlorophytum comosum (Thunb.) Jacques and Eichhornia crassipes (Mart.) Solms, to low LET gamma radiation with special emphasis on the pattern of micronuclei induced across low and high dose regimes. A tri-phasic non-linear dose-response pattern was observed in the four taxa studied, characterized by a low dose linear segment, a plateau and a high dose linear segment. Despite a similar response trend, the critical doses where the phase transitions occurred varied amongst the plant taxa, giving an indication to their relative radiosensitivities. E. crassipes and A. sativum, with their lower critical doses for slope modifications of phase transitions, were concluded as being more radiosensitive as compared to C. comosum and A. cepa, which had relatively higher critical doses. (author)

  19. Impact of radiation dose and standardized uptake value of (18)FDG PET on nodal control in locally advanced cervical cancer

    DEFF Research Database (Denmark)

    Ramlov, Anne; Kroon, Petra S; Jürgenliemk-Schulz, Ina M

    2015-01-01

    BACKGROUND: Despite local control now exceeding 90% with image-guided adaptive brachytherapy (IGABT), regional and distant metastases continue to curb survival in locally advanced cervical cancer. As regional lymph nodes often represent first site of metastatic spread, improved nodal control could...... improve survival. The aim of this study was to examine optimal volume and dose of external beam radiotherapy (EBRT) to maximize regional control including dose contribution from IGABT. MATERIAL AND METHODS: In total 139 patients from the EMBRACE study were analyzed. Individual nodal dose was determined...

  20. Nature, frequency and determinants of prescription modifications in Dutch community pharmacies

    Science.gov (United States)

    Buurma, Henk; de Smet, Peter A G M; van den Hoff, Olga P; Egberts, Antoine C G

    2001-01-01

    Aims To examine the nature, frequency and determinants of prescription modifications in Dutch community pharmacies. Methods A prospective case-control study comparing modified prescriptions with nonmodified prescriptions was carried out in 141 Dutch community pharmacies. 2014 modified prescriptions (cases), collected in the selected pharmacies on a predetermined day in a specific period (25th February until 12th March 1999) and 2581 nonmodified prescriptions (controls) randomly selected on the same day were studied. The nature and frequency of prescription modifications and patient, drug and prescriber related determinants for a modified prescription were assessed. Results The overall incidence of prescription modifications was 4.3%, with a mean of 14.3 modifications per pharmacy per day. For prescription only medicines (POM) the incidence was 4.9%. The majority of POM modifications concerned a clarification (71.8%). In 22.2% a prescription could potentially have had clinical consequences when not altered; in more than half of the latter it concerned a dose error (13.7% of all cases). POM prescriptions of patients of 40–65 years had a significantly lower chance of modification compared with those of younger people (OR = 0.74 [0.64–0.86]). With respect to medication-class, we found a higher chance of POM modifications in the respiratory domain (OR = 1.48 [1.23-1.79]) and a decreased chance for nervous system POMs (OR = 0.71 [0.61–0.83]). With regard to prescriber-related determinants modifications were found three times more often in non printed prescriptions than in printed ones (OR = 3.30 [2.90-3.75]). Compared with prescriptions by the patient's own GP, prescriptions of specialists (OR = 1.82 [1.57-2.11]), other GP's (OR = 1.49 [1.02-2.17]) and other prescribers such as dentists and midwives (OR = 1.95 [1.06-3.57]) gave a higher probability of prescription modifications. When a GP had no on-line access to the computer of the pharmacy the chance of a

  1. Real-World Dosing Patterns of Atomoxetine in Adults with Attention-Deficit/Hyperactivity Disorder.

    Science.gov (United States)

    Kabul, Samaneh; Alatorre, Carlos; Montejano, Leslie B; Farr, Amanda M; Clemow, David B

    2015-12-01

    The aim was to investigate the dosing patterns of atomoxetine monotherapy in adult patients with attention-deficit/hyperactivity disorder (ADHD) in a retrospective analysis. Adult (≥ 18 years) patients with ADHD newly initiated on atomoxetine with ≥ 1 outpatient pharmacy claim for atomoxetine between January 2006 and December 2011 were selected from the Truven Health MarketScan(®) Commercial database. After a 30-day titration period, dosing patterns of atomoxetine monotherapy were analyzed in the 12 months following initiation. In addition, patient demographic and clinical characteristics were compared to identify characteristics associated with suboptimal versus recommended dosing. Of the 12,412 adult patients with ADHD newly initiated on atomoxetine, 4548 (36.6%) were suboptimally dosed, whereas 3323 (26.7%) were treated at recommended dose. Overall, study patients were treated at a mean (standard deviation [SD]) dose of 68.5 (44.9) mg/day. The suboptimal dosing cohort included significantly more females (54% vs. 44%, P atomoxetine therapy in a real-world setting are often dosed suboptimally. Increasing the awareness on optimal dosing strategy among clinicians and patients is warranted to maximize the therapeutic benefits of atomoxetine among adult patients with ADHD. © 2015 Eli Lilly and Company. CNS Neuroscience and Therapeutics published by John Wiley & Sons Ltd.

  2. Effect of gamma irradiation at intermediate doses on the performance of reverse osmosis membranes

    International Nuclear Information System (INIS)

    Combernoux, Nicolas; Labed, Véronique; Schrive, Luc; Wyart, Yvan; Carretier, Emilie; Moulin, Philippe

    2016-01-01

    The goal of this study is to explain the degradation of Polyamide (PA) composite reverse osmosis membrane (RO) in function of the irradiation dose. Irradiations were performed with a gamma 60 Co source in wet conditions and under oxygen atmosphere. For different doses of 0.2 and 0.5 MGy with a constant dose rate of 0.5 kGy h −1 , RO membranes performances (NaCl retention, permeability) were studied before and after irradiation. ATR-FTIR, ion chromatography and gas chromatography were used to characterize structural modification. Results showed that the permeability of RO membranes irradiated at 0.2 MGy exhibited a small decrease, related to scissions of the PVA coating. However, retention did not change at this dose. At 0.5 MGy, permeability showed a large increase of a factor around 2 and retention began to decrease from 99% to 95%. Chromatography measurements revealed a strong link between permselectivity properties variation, ion leakage and oxygen consumption. Add to ATR-FTIR observations, these results emphasized that the cleavages of amide and ester bonds were observed at 0.5 MGy, more precisely the loss of hydrogen bonds between polyamide chains. By different analysis, modifications of the polysulfone layer occur until a dose of 0.2 MGy. - Highlights: • Irradiation of RO membranes at intermediate dose (0.2 and 0.5 MGy). • For a dose rate of 0.5 kGy h −1 RO membranes are radiation resistant until 0.2 MGy. • Cleavages of polymer bonds in the active layer at 0.5 MGy. • Decrease in permselectivity properties of the membrane at 0.5 MGy. • High oxygen consumption between 0.2 and 0.5 MGy related to the membranes degradation.

  3. Enumerating all maximal frequent subtrees in collections of phylogenetic trees.

    Science.gov (United States)

    Deepak, Akshay; Fernández-Baca, David

    2014-01-01

    A common problem in phylogenetic analysis is to identify frequent patterns in a collection of phylogenetic trees. The goal is, roughly, to find a subset of the species (taxa) on which all or some significant subset of the trees agree. One popular method to do so is through maximum agreement subtrees (MASTs). MASTs are also used, among other things, as a metric for comparing phylogenetic trees, computing congruence indices and to identify horizontal gene transfer events. We give algorithms and experimental results for two approaches to identify common patterns in a collection of phylogenetic trees, one based on agreement subtrees, called maximal agreement subtrees, the other on frequent subtrees, called maximal frequent subtrees. These approaches can return subtrees on larger sets of taxa than MASTs, and can reveal new common phylogenetic relationships not present in either MASTs or the majority rule tree (a popular consensus method). Our current implementation is available on the web at https://code.google.com/p/mfst-miner/. Our computational results confirm that maximal agreement subtrees and all maximal frequent subtrees can reveal a more complete phylogenetic picture of the common patterns in collections of phylogenetic trees than maximum agreement subtrees; they are also often more resolved than the majority rule tree. Further, our experiments show that enumerating maximal frequent subtrees is considerably more practical than enumerating ordinary (not necessarily maximal) frequent subtrees.

  4. Softly Broken Lepton Numbers: an Approach to Maximal Neutrino Mixing

    International Nuclear Information System (INIS)

    Grimus, W.; Lavoura, L.

    2001-01-01

    We discuss models where the U(1) symmetries of lepton numbers are responsible for maximal neutrino mixing. We pay particular attention to an extension of the Standard Model (SM) with three right-handed neutrino singlets in which we require that the three lepton numbers L e , L μ , and L τ be separately conserved in the Yukawa couplings, but assume that they are softly broken by the Majorana mass matrix M R of the neutrino singlets. In this framework, where lepton-number breaking occurs at a scale much higher than the electroweak scale, deviations from family lepton number conservation are calculable, i.e., finite, and lepton mixing stems exclusively from M R . We show that in this framework either maximal atmospheric neutrino mixing or maximal solar neutrino mixing or both can be imposed by invoking symmetries. In this way those maximal mixings are stable against radiative corrections. The model which achieves maximal (or nearly maximal) solar neutrino mixing assumes that there are two different scales in M R and that the lepton number (dash)L=L e -L μ -L τ 1 is conserved in between them. We work out the difference between this model and the conventional scenario where (approximate) (dash)L invariance is imposed directly on the mass matrix of the light neutrinos. (author)

  5. The Impact of a One-Dose versus Two-Dose Oral Cholera Vaccine Regimen in Outbreak Settings: A Modeling Study

    Science.gov (United States)

    Azman, Andrew S.; Luquero, Francisco J.; Ciglenecki, Iza; Grais, Rebecca F.; Sack, David A.; Lessler, Justin

    2015-01-01

    Background In 2013, a stockpile of oral cholera vaccine (OCV) was created for use in outbreak response, but vaccine availability remains severely limited. Innovative strategies are needed to maximize the health impact and minimize the logistical barriers to using available vaccine. Here we ask under what conditions the use of one dose rather than the internationally licensed two-dose protocol may do both. Methods and Findings Using mathematical models we determined the minimum relative single-dose efficacy (MRSE) at which single-dose reactive campaigns are expected to be as or more effective than two-dose campaigns with the same amount of vaccine. Average one- and two-dose OCV effectiveness was estimated from published literature and compared to the MRSE. Results were applied to recent outbreaks in Haiti, Zimbabwe, and Guinea using stochastic simulations to illustrate the potential impact of one- and two-dose campaigns. At the start of an epidemic, a single dose must be 35%–56% as efficacious as two doses to avert the same number of cases with a fixed amount of vaccine (i.e., MRSE between 35% and 56%). This threshold decreases as vaccination is delayed. Short-term OCV effectiveness is estimated to be 77% (95% CI 57%–88%) for two doses and 44% (95% CI −27% to 76%) for one dose. This results in a one-dose relative efficacy estimate of 57% (interquartile range 13%–88%), which is above conservative MRSE estimates. Using our best estimates of one- and two-dose efficacy, we projected that a single-dose reactive campaign could have prevented 70,584 (95% prediction interval [PI] 55,943–86,205) cases in Zimbabwe, 78,317 (95% PI 57,435–100,150) in Port-au-Prince, Haiti, and 2,826 (95% PI 2,490–3,170) cases in Conakry, Guinea: 1.1 to 1.2 times as many as a two-dose campaign. While extensive sensitivity analyses were performed, our projections of cases averted in past epidemics are based on severely limited single-dose efficacy data and may not fully capture

  6. The Impact of a One-Dose versus Two-Dose Oral Cholera Vaccine Regimen in Outbreak Settings: A Modeling Study.

    Directory of Open Access Journals (Sweden)

    Andrew S Azman

    2015-08-01

    Full Text Available In 2013, a stockpile of oral cholera vaccine (OCV was created for use in outbreak response, but vaccine availability remains severely limited. Innovative strategies are needed to maximize the health impact and minimize the logistical barriers to using available vaccine. Here we ask under what conditions the use of one dose rather than the internationally licensed two-dose protocol may do both.Using mathematical models we determined the minimum relative single-dose efficacy (MRSE at which single-dose reactive campaigns are expected to be as or more effective than two-dose campaigns with the same amount of vaccine. Average one- and two-dose OCV effectiveness was estimated from published literature and compared to the MRSE. Results were applied to recent outbreaks in Haiti, Zimbabwe, and Guinea using stochastic simulations to illustrate the potential impact of one- and two-dose campaigns. At the start of an epidemic, a single dose must be 35%-56% as efficacious as two doses to avert the same number of cases with a fixed amount of vaccine (i.e., MRSE between 35% and 56%. This threshold decreases as vaccination is delayed. Short-term OCV effectiveness is estimated to be 77% (95% CI 57%-88% for two doses and 44% (95% CI -27% to 76% for one dose. This results in a one-dose relative efficacy estimate of 57% (interquartile range 13%-88%, which is above conservative MRSE estimates. Using our best estimates of one- and two-dose efficacy, we projected that a single-dose reactive campaign could have prevented 70,584 (95% prediction interval [PI] 55,943-86,205 cases in Zimbabwe, 78,317 (95% PI 57,435-100,150 in Port-au-Prince, Haiti, and 2,826 (95% PI 2,490-3,170 cases in Conakry, Guinea: 1.1 to 1.2 times as many as a two-dose campaign. While extensive sensitivity analyses were performed, our projections of cases averted in past epidemics are based on severely limited single-dose efficacy data and may not fully capture uncertainty due to imperfect

  7. Maximal heart rate does not limit cardiovascular capacity in healthy humans

    DEFF Research Database (Denmark)

    Munch, G D W; Svendsen, J H; Damsgaard, R

    2014-01-01

    In humans, maximal aerobic power (VO2 max ) is associated with a plateau in cardiac output (Q), but the mechanisms regulating the interplay between maximal heart rate (HRmax) and stroke volume (SV) are unclear. To evaluate the effect of tachycardia and elevations in HRmax on cardiovascular function...... and capacity during maximal exercise in healthy humans, 12 young male cyclists performed incremental cycling and one-legged knee-extensor exercise (KEE) to exhaustion with and without right atrial pacing to increase HR. During control cycling, Q and leg blood flow increased up to 85% of maximal workload (WLmax...... and RAP (P healthy...

  8. Limits of dose escalation in lung cancer: a dose-volume histogram analysis comparing coplanar and non-coplanar techniques

    Energy Technology Data Exchange (ETDEWEB)

    Derycke, S; Van Duyse, B; Schelfhout, J; De Neve, W

    1995-12-01

    To evaluate the feasibility of dose escalation in radiotherapy of inoperable lung cancer, a dose-volume histogram analysis was performed comparing standard coplanar (2D) with non-coplanar (3D) beam arrangements on a non-selected group of 20 patients planned by Sherouse`s GRATISTM 3D-planning system. Serial CT-scanning was performed and 2 Target Volumes (Tvs) were defined. Gross Tumor Volume (GTV) defined a high-dose Target Volume (TV-1). GTV plus location of node stations with > 10% probability of invasion (Minet et al.) defined an intermediate-dose Target Volume (TV-2). However, nodal regions which are incompatible with cure were excluded from TV-2. These are ATS-regions 1, 8, 9 and 14 all left and right as well as heterolateral regions. For 3D-planning, Beam`s Eye View selected (by an experienced planner) beam arrangements were optimised using Superdot, a method of target dose-gradient annihilation developed by Sherouse. A second 3D-planning was performed using 4 beam incidences with maximal angular separation. The linac`s isocenter for the optimal arrangement was located at the geometrical center of gravity of a tetraheder, the tetraheder`s comers being the consecutive positions of the virtual source. This ideal beam arrangement was approximated as close as possible, taking into account technical limitations (patient-couch-gantry collisions). Criteria for tolerance were met if no points inside the spinal cord exceeded 50 Gy and if at least 50% of the lung volume received less than 20Gy. If dose regions below 50 Gy were judged acceptable at TV-2, 2D- as well as 3D-plans allow safe escalation to 80 Gy at TV-1. When TV-2 needed to be encompassed by isodose surfaces exceeding 50Gy, 3D-plans were necessary to limit dose at the spinal cord below tolerance. For large TVs dose is limited by lung tolerance for 3D-plans. An analysis (including NTCP-TCP as cost functions) of rival 3D-plans is being performed.

  9. Power Converters Maximize Outputs Of Solar Cell Strings

    Science.gov (United States)

    Frederick, Martin E.; Jermakian, Joel B.

    1993-01-01

    Microprocessor-controlled dc-to-dc power converters devised to maximize power transferred from solar photovoltaic strings to storage batteries and other electrical loads. Converters help in utilizing large solar photovoltaic arrays most effectively with respect to cost, size, and weight. Main points of invention are: single controller used to control and optimize any number of "dumb" tracker units and strings independently; power maximized out of converters; and controller in system is microprocessor.

  10. No Mikheyev-Smirnov-Wolfenstein Effect in Maximal Mixing

    OpenAIRE

    Harrison, P. F.; Perkins, D. H.; Scott, W. G.

    1996-01-01

    We investigate the possible influence of the MSW effect on the expectations for the solar neutrino experiments in the maximal mixing scenario suggested by the atmospheric neutrino data. A direct numerical calculation of matter induced effects in the Sun shows that the naive vacuum predictions are left completely undisturbed in the particular case of maximal mixing, so that the MSW effect turns out to be unobservable. We give a qualitative explanation of this result.

  11. Radiological Dose Calculations And Supplemental Dose Assessment Data For Neshap Compliance For SNL Nevada Facilities 1996.

    Energy Technology Data Exchange (ETDEWEB)

    None, None

    2017-05-01

    Operations of Sandia National Laboratories, Nevada (SNL/NV) at the Tonopah Test Range (TTR) resulted in no planned point radiological releases during 1996. Other releases from SNL/NV included diffuse transuranic sources consisting of the three Clean Slate sites. Air emissions from these sources result from wind resuspension of near-surface transuranic contaminated soil particulates. The total area of contamination has been estimated to exceed 20 million square meters. Soil contamination was documented in an aerial survey program in 1977 (EG&G 1979). Surface contamination levels were generally found to be below 400 pCi/g of combined plutonium-238, plutonium-239, plutonium-240, and americium-241 (i.e., transuranic) activity. Hot spot areas contain up to 43,000 pCi/g of transuranic activity. Recent measurements confirm the presence of significant levels of transuranic activity in the surface soil. An annual diffuse source term of 0.39 Ci of transuranic material was calculated for the cumulative release from all three Clean Slate sites. A maximally exposed individual dose of 1.1 mrem/yr at the TTR airport area was estimated based on the 1996 diffuse source release amounts and site-specific meteorological data. A population dose of 0.86 person-rem/yr was calculated for the local residents. Both dose values were attributable to inhalation of transuranic contaminated dust.

  12. Single maximal versus combination punch kinematics.

    Science.gov (United States)

    Piorkowski, Barry A; Lees, Adrian; Barton, Gabor J

    2011-03-01

    The aim of this study was to determine the influence of punch type (Jab, Cross, Lead Hook and Reverse Hook) and punch modality (Single maximal, 'In-synch' and 'Out of synch' combination) on punch speed and delivery time. Ten competition-standard volunteers performed punches with markers placed on their anatomical landmarks for 3D motion capture with an eight-camera optoelectronic system. Speed and duration between key moments were computed. There were significant differences in contact speed between punch types (F(2,18,84.87) = 105.76, p = 0.001) with Lead and Reverse Hooks developing greater speed than Jab and Cross. There were significant differences in contact speed between punch modalities (F(2,64,102.87) = 23.52, p = 0.001) with the Single maximal (M+/- SD: 9.26 +/- 2.09 m/s) higher than 'Out of synch' (7.49 +/- 2.32 m/s), 'In-synch' left (8.01 +/- 2.35 m/s) or right lead (7.97 +/- 2.53 m/s). Delivery times were significantly lower for Jab and Cross than Hook. Times were significantly lower 'In-synch' than a Single maximal or 'Out of synch' combination mode. It is concluded that a defender may have more evasion-time than previously reported. This research could be of use to performers and coaches when considering training preparations.

  13. Formation Control for the MAXIM Mission

    Science.gov (United States)

    Luquette, Richard J.; Leitner, Jesse; Gendreau, Keith; Sanner, Robert M.

    2004-01-01

    Over the next twenty years, a wave of change is occurring in the space-based scientific remote sensing community. While the fundamental limits in the spatial and angular resolution achievable in spacecraft have been reached, based on today s technology, an expansive new technology base has appeared over the past decade in the area of Distributed Space Systems (DSS). A key subset of the DSS technology area is that which covers precision formation flying of space vehicles. Through precision formation flying, the baselines, previously defined by the largest monolithic structure which could fit in the largest launch vehicle fairing, are now virtually unlimited. Several missions including the Micro-Arcsecond X-ray Imaging Mission (MAXIM), and the Stellar Imager will drive the formation flying challenges to achieve unprecedented baselines for high resolution, extended-scene, interferometry in the ultraviolet and X-ray regimes. This paper focuses on establishing the feasibility for the formation control of the MAXIM mission. MAXIM formation flying requirements are on the order of microns, while Stellar Imager mission requirements are on the order of nanometers. This paper specifically addresses: (1) high-level science requirements for these missions and how they evolve into engineering requirements; and (2) the development of linearized equations of relative motion for a formation operating in an n-body gravitational field. Linearized equations of motion provide the ground work for linear formation control designs.

  14. Conversational Implicature of Peanuts Comic Strip Based on Grice’s Maxim Theory

    Directory of Open Access Journals (Sweden)

    Muhartoyo Muhartoyo

    2013-04-01

    Full Text Available This article discusses about conversational implicature that occurs in Peanuts comic strips. The objectives of this study are to find out the implied meaning in the conversation between Charlie Brown with Lucy van Pelt and Lucy van Pelt with Linus van Pelt to evaluate the existence of maxim flouting and maxim violating in those conversations in relation to the four maxims such as quantity, quality, relation, and manner. Likewise, this study attempts to find out the reason for using conversational implicature in a comic strip. The writers uses a qualitative method with library research concerning to Grice’s maxim theory to analyze the conversational implicature. Based on the analysis, it can be concluded that all the comics that comprise 14 comics generate conversational implicature since all the characters breach rules of maxim. The result of this analysis shows that flouting maxim of manner has the highest occurrence of conversational implicature and the least occurrences belong to flouting maxim of relation and violating maxim of quantity. Moreover, the writers concludes that to make a successful communication ideally the speaker and the hearer to cooperate in the conversation by saying explicitly so the hearer can grasp the meaning as the goal of communication is to deliver a message to the hearer.  

  15. Modifications to POISSON

    International Nuclear Information System (INIS)

    Harwood, L.H.

    1981-01-01

    At MSU we have used the POISSON family of programs extensively for magnetic field calculations. In the presently super-saturated computer situation, reducing the run time for the program is imperative. Thus, a series of modifications have been made to POISSON to speed up convergence. Two of the modifications aim at having the first guess solution as close as possible to the final solution. The other two aim at increasing the convergence rate. In this discussion, a working knowledge of POISSON is assumed. The amount of new code and expected time saving for each modification is discussed

  16. Comparison of changes in the mobility of the pelvic floor muscle on during the abdominal drawing-in maneuver, maximal expiration, and pelvic floor muscle maximal contraction.

    Science.gov (United States)

    Jung, Halim; Jung, Sangwoo; Joo, Sunghee; Song, Changho

    2016-01-01

    [Purpose] The purpose of this study was to compare changes in the mobility of the pelvic floor muscle during the abdominal drawing-in maneuver, maximal expiration, and pelvic floor muscle maximal contraction. [Subjects] Thirty healthy adults participated in this study (15 men and 15 women). [Methods] All participants performed a bridge exercise and abdominal curl-up during the abdominal drawing-in maneuver, maximal expiration, and pelvic floor muscle maximal contraction. Pelvic floor mobility was evaluated as the distance from the bladder base using ultrasound. [Results] According to exercise method, bridge exercise and abdominal curl-ups led to significantly different pelvic floor mobility. The pelvic floor muscle was elevated during the abdominal drawing-in maneuver and descended during maximal expiration. Finally, pelvic floor muscle mobility was greater during abdominal curl-up than during the bridge exercise. [Conclusion] According to these results, the abdominal drawing-in maneuver induced pelvic floor muscle contraction, and pelvic floor muscle contraction was greater during the abdominal curl-up than during the bridge exercise.

  17. Descriptive Analysis on Flouting and Hedging of Conversational Maxims in the “Post Grad” Movie

    Directory of Open Access Journals (Sweden)

    Nastiti Rokhmania

    2012-11-01

    Full Text Available This research is focused on analyzing flouting and hedging of conversational maxim of utterances used by the main characters in “Post Grad” movie. Conversational maxims are the rules of cooperative principle categorized into four categories; Maxim of Quality, Maxim of Quantity, Maxim of Relevance, and Maxim of Manner. If these maxims are used in conversations, the conversations can go smoothly. However, people often break the maxims overtly (flouting maxim and sometimes break the maxims secretly (hedging maxims when they make a conversation. This research is conducted using descriptive qualitative method based on the theory known as Grice’s Maxims. The data are in form of utterances used by the characters in “Post Grad” movie. The data analysis reveals some finding covering the formulated research question. The maxims are flouted when the speaker breaks some conversational maxims when using the utterances in the form of rhetorical strategies, such as tautology, metaphor, hyperbole, irony, and rhetorical question. On the other hand, conversational maxims are also hedged when the information is not totally accurate or unclearly stated but seems informative, well-founded, and relevant.

  18. Efficacy and tolerability of high-dose phenobarbital in children with focal seizures.

    Science.gov (United States)

    Okumura, Akihisa; Nakahara, Eri; Ikeno, Mitsuru; Abe, Shinpei; Igarashi, Ayuko; Nakazawa, Mika; Takasu, Michihiko; Shimizu, Toshiaki

    2016-04-01

    We retrospectively reviewed the outcomes of children with focal epilepsy treated with oral high-dose phenobarbital. We reviewed data on children (agedphenobarbital (>5 mg/kg/day to maintain a target serum level >40 μg/mL) for at least 6 months. Seizure frequency was evaluated after phenobarbital titration, and 1 and 2 years after high-dose phenobarbital treatment commenced. Treatment was judged effective when seizure frequencies fell by ⩾75%. Seven boys and eight girls were treated. The median age at commencement of high-dose phenobarbital therapy was 30 months. The maximal serum phenobarbital level ranged from 36.5 to 62.9 μg/mL. High-dose PB was effective in seven. In two patients, treatment was transiently effective, but seizure frequency later returned to the baseline. High-dose PB was ineffective in six. No significant association between effectiveness and any clinical variable was evident. Drowsiness was recorded in nine patients, but no patient developed a behavioral problem or hypersensitivity. Oral high-dose phenobarbital was effective in 7 of 15 patients with focal epilepsy and well tolerated. High-dose PB may be useful when surgical treatment is difficult. Copyright © 2015 The Japanese Society of Child Neurology. Published by Elsevier B.V. All rights reserved.

  19. Dose prescription complexity versus tumor control probability in biologically conformal radiotherapy

    International Nuclear Information System (INIS)

    South, C. P.; Evans, P. M.; Partridge, M.

    2009-01-01

    The technical feasibility and potential benefits of voxel-based nonuniform dose prescriptions for biologically heterogeneous tumors have been widely demonstrated. In some cases, an ''ideal'' dose prescription has been generated by individualizing the dose to every voxel within the target, but often this voxel-based prescription has been discretized into a small number of compartments. The number of dose levels utilized and the methods used for prescribing doses and assigning tumor voxels to different dose compartments have varied significantly. The authors present an investigation into the relationship between the complexity of the dose prescription and the tumor control probability (TCP) for a number of these methods. The linear quadratic model of cell killing was used in conjunction with a number of modeled tumors heterogeneous in clonogen density, oxygenation, or proliferation. Models based on simple mathematical functions, published biological data, and biological image data were investigated. Target voxels were assigned to dose compartments using (i) simple rules based on the initial biological distribution, (ii) iterative methods designed to maximize the achievable TCP, or (iii) methods based on an ideal dose prescription. The relative performance of the simple rules was found to depend on the form of heterogeneity of the tumor, while the iterative and ideal dose methods performed comparably for all models investigated. In all cases the maximum achievable TCP was approached within the first few (typically two to five) compartments. Results suggest that irrespective of the pattern of heterogeneity, the optimal dose prescription can be well approximated using only a few dose levels but only if both the compartment boundaries and prescribed dose levels are well chosen.

  20. Treatment of advanced pancreatic carcinoma with 90Y-Clivatuzumab Tetraxetan: a phase I single-dose escalation trial.

    Science.gov (United States)

    Gulec, Seza A; Cohen, Steven J; Pennington, Kenneth L; Zuckier, Lionel S; Hauke, Ralph J; Horne, Heather; Wegener, William A; Teoh, Nick; Gold, David V; Sharkey, Robert M; Goldenberg, David M

    2011-06-15

    Humanized antibody hPAM4 specifically binds a mucin glycoprotein expressed in pancreatic adenocarcinomas. This phase I study evaluated a single dose of (90)Y-clivatuzumab tetraxetan ((90)Y-labeled hPAM4) in patients with advanced pancreatic cancer. Twenty-one patients (4 stage III; 17 stage IV) received (111)In-hPAM4 for imaging and serum sampling before (90)Y-hPAM4. Study procedures evaluated adverse events, safety laboratories, computed tomography (CT) scans, biomarkers, pharmacokinetics, radiation dosimetry, and immunogenicity (HAHA). (111)In-hPAM4 showed normal biodistribution with radiation dose estimates to red marrow and solid organs acceptable for radioimmunotherapy and with tumor targeting in 12 patients. One patient withdrew before (90)Y-hPAM4; otherwise, 20 patients received (90)Y doses of 15 (n = 7), 20 (n = 9), and 25 mCi/m(2) (n = 4). Treatment was well tolerated; the only significant drug-related toxicities were (NCI CTC v.3) grade 3 to 4 neutropenia and thrombocytopenia increasing with (90)Y dose. There were no bleeding events or serious infections, and most cytopenias recovered to grade 1 within 12 weeks. Three patients at 25 mCi/m(2) encountered dose-limiting toxicity with grade 4 cytopenias more than 7 days, establishing 20 mCi/m(2) as the maximal tolerated (90)Y dose. Two patients developed HAHA of uncertain clinical significance. Most patients progressed rapidly and with CA19-9 levels increasing within 1 month of therapy, but 7 remained progression-free by CT for 1.5 to 5.6 months, including 3 achieving transient partial responses (32%-52% tumor diameter shrinkage). (90)Y-Clivatuzumab tetraxetan was well tolerated with manageable hematologic toxicity at the maximal tolerated (90)Y dose, and is a potential new therapeutic for advanced pancreatic cancer. ©2011 AACR.

  1. Maximal and anaerobic threshold cardiorespiratory responses during deepwater running

    Directory of Open Access Journals (Sweden)

    Ana Carolina Kanitz

    2014-12-01

    Full Text Available DOI: http://dx.doi.org/10.5007/1980-0037.2015v17n1p41   Aquatic exercises provide numerous benefits to the health of their practitioners. To secure these benefits, it is essential to have proper prescriptions to the needs of each individual and, therefore, it is important to study the cardiorespiratory responses of different activities in this environment. Thus, the aim of this study was to compare the cardiorespiratory responses at the anaerobic threshold (AT between maximal deep-water running (DWR and maximal treadmill running (TMR. In addition, two methods of determining the AT (the heart rate deflection point [HRDP] and ventilatory method [VM] are compared in the two evaluated protocols. Twelve young women performed the two maximal protocols. Two-factor ANOVA for repeated measures with a post-hoc Bonferroni test was used (α < 0.05. Significantly higher values of maximal heart rate (TMR: 33.7 ± 3.9; DWR: 22.5 ± 4.1 ml.kg−1.min−1 and maximal oxygen uptake (TMR: 33.7 ± 3.9; DWR: 22.5 ± 4.1 ml.kg−1.min−1 in TMR compared to the DWR were found. Furthermore, no significant differences were found between the methods for determining the AT (TMR: VM: 28.1 ± 5.3, HRDP: 26.6 ± 5.5 ml.kg−1.min−1; DWR: VM: 18.7 ± 4.8, HRDP: 17.8 ± 4.8 ml.kg−1.min−1. The results indicate that a specific maximal test for the trained modality should be conducted and the HRDP can be used as a simple and practical method of determining the AT, based on which the training intensity can be determined

  2. High-dose buprenorphine: perioperative precautions and management strategies.

    Science.gov (United States)

    Roberts, D M; Meyer-Witting, M

    2005-02-01

    Buprenorphine has been in clinical use in anaesthesia for several decades. Recently, the high-dose sublingual formulation (Subutex, Reckitt Benckiser, Slough, U.K.) has been increasingly used as maintenance therapy in opioid dependence, as an alternative to methadone and other pharmacological therapies. Buprenorphine has unique pharmacological properties making it well suited for use as a maintenance therapy in opioid dependence. However, these same properties may cause difficulty in the perioperative management of pain. Buprenorphine is a partial opioid agonist, attenuating the effects of supplemental illicit or therapeutic opioid agonists. As a result of its high receptor affinity, supplemental opioids do not readily displace buprenorphine from the opioid receptor in standard doses. High-dose buprenorphine has an extended duration of action that prolongs both of these effects. The perioperative management of patients stabilized on high-dose buprenorphine and undergoing surgery requires consideration of the likely analgesic requirements. Where possible the buprenorphine should be continued. Pain management should focus on maximizing non-opioid analgesia, local anaesthesia and non-pharmacological techniques. Where pain may not be adequately relieved by these methods, the addition of a full opioid agonist such as fentanyl or morphine at appropriate doses should be considered, accompanied by close monitoring in a high dependency unit. In situations where this regimen is unlikely to be effective, preoperative conversion to morphine or methadone may be an option. Where available, liaison with a hospital-based alcohol and drug service should always be considered.

  3. Adaptation of Lorke's method to determine and compare ED50 values: the cases of two anticonvulsants drugs.

    Science.gov (United States)

    Garrido-Acosta, Osvaldo; Meza-Toledo, Sergio Enrique; Anguiano-Robledo, Liliana; Valencia-Hernández, Ignacio; Chamorro-Cevallos, Germán

    2014-01-01

    We determined the median effective dose (ED50) values for the anticonvulsants phenobarbital and sodium valproate using a modification of Lorke's method. This modification allowed appropriate statistical analysis and the use of a smaller number of mice per compound tested. The anticonvulsant activities of phenobarbital and sodium valproate were evaluated in male CD1 mice by maximal electroshock (MES) and intraperitoneal administration of pentylenetetrazole (PTZ). The anticonvulsant ED50 values were obtained through modifications of Lorke's method that involved changes in the selection of the three first doses in the initial test and the fourth dose in the second test. Furthermore, a test was added to evaluate the ED50 calculated by the modified Lorke's method, allowing statistical analysis of the data and determination of the confidence limits for ED50. The ED50 for phenobarbital against MES- and PTZ-induced seizures was 16.3mg/kg and 12.7mg/kg, respectively. The sodium valproate values were 261.2mg/kg and 159.7mg/kg, respectively. These results are similar to those found using the traditional methods of finding ED50, suggesting that the modifications made to Lorke's method generate equal results using fewer mice while increasing confidence in the statistical analysis. This adaptation of Lorke's method can be used to determine median letal dose (LD50) or ED50 for compounds with other pharmacological activities. Copyright © 2014 Elsevier Inc. All rights reserved.

  4. Pharmacokinetics of diclofenac in pigs after intramuscular administration of a single dose

    OpenAIRE

    Pejčić Zorica; Pokrajac Milena; Jezdimirović Milanka

    2006-01-01

    The pharmacokinetics of diclofenac was studied in 10 clinically normal male Yorkshire pigs, following intramuscular (i.m) administration of a single dose of diclofenac-sodium (2.5 mg/kg body weight). Diclofenac serum concentrations were determined by high pressure- liquid-chromatography (HPLC), with UV detection (226 nm). Following i.m. administration all individual diclofenac serum levels best fitted the one-compartment open model for extravascular administration. The maximal diclofenac seru...

  5. EFFECT OF ENERGY EXPENDITURE AND TRAINING STATUS ON LEPTIN RESPONSE TO SUB-MAXIMAL CYCLING

    Directory of Open Access Journals (Sweden)

    Anissa Bouassida

    2009-06-01

    Full Text Available We examined the leptin response and related hormones during and after two sub-maximal exercise protocols in trained and untrained subjects. During this study, plasma concentrations of leptin [Lep], insulin [I], cortisol [C], growth hormone [GH], glucose [G] and lactate [La] were measured. 7 elite volleyball trained players (TR and 7 untrained (UTR subjects (percent body fat: 13.2 ± 1.8 versus 15.7 ± 1.0, p < 0.01, respectively were examined after short and prolonged sub-maximal cycling exercise protocols (SP and PP. Venous blood samples were collected before each protocol, during, at the end, and after 2 and 24 h of recovery. SP and PP energy expenditures ranged from 470 ± 60 to 740 ± 90 kcal for TR and from 450 ± 60 to 710 ± 90 kcal for UTR, respectively. [Lep] was related to body fat percentage and body fat mass in TR (r = 0. 84, p < 0.05 and r = 0.93, p < 0.01 and in UTR (r = 0.89, p < 0.01 and r = 0.92, p < 0. 01, respectively. [Lep] did not change significantly during both protocols for both groups but was lower (p < 0.05 in all sampling in TR when compared to UTR. Plasma [I] decreased (p < 0.01 and [GH] increased (p < 0.01 significantly during both SP and PP and these hormones remained lower (I: p < 0.01 and higher (GH: p < 0.01 than pre-exercise levels after a 2-h recovery period, returning to base-line at 24-h recovery. Plasma [La] increased (p < 0.01 during both protocols for TR and UTR. There was no significant change in [C] and [G] during and after both protocols for all subjects. It is concluded that 1 leptin is not sensitive to acute short or prolonged sub-maximal exercises (with energy expenditure under 800 kcal in volleyball/ anaerobically trained athletes as in untrained subjects, 2 volleyball athletes showed significantly lower resting and exercise leptin response with respect to untrained subjects and 3 it appears that in these anaerobically trained athletes leptin response to exercise is more sensitive to the level of

  6. Quantization with maximally degenerate Poisson brackets: the harmonic oscillator!

    International Nuclear Information System (INIS)

    Nutku, Yavuz

    2003-01-01

    Nambu's construction of multi-linear brackets for super-integrable systems can be thought of as degenerate Poisson brackets with a maximal set of Casimirs in their kernel. By introducing privileged coordinates in phase space these degenerate Poisson brackets are brought to the form of Heisenberg's equations. We propose a definition for constructing quantum operators for classical functions, which enables us to turn the maximally degenerate Poisson brackets into operators. They pose a set of eigenvalue problems for a new state vector. The requirement of the single-valuedness of this eigenfunction leads to quantization. The example of the harmonic oscillator is used to illustrate this general procedure for quantizing a class of maximally super-integrable systems

  7. Effectance, committed effective dose equivalent and annual limits on intake: what are the changes?

    International Nuclear Information System (INIS)

    Kendall, G.M.; Stather, J.W.; Phipps, A.W.

    1990-01-01

    This paper outlines the concept of effectance, compares committed effectance with the old committed effective dose equivalent and goes on to discuss changes in the annual limits on intakes and the maximum organ doses which would result from an intake of an ALI (Annual Limit of Intake). It is shown that committed effectance is usually, but not always, higher than committed effective dose equivalent. ALIS are usually well below those resulting from the ICRP Publication 30 scheme. However, if the ALI were based only on a limit on effectance it would imply a high dose to specific organs for certain nuclides. In order to control maximum organ doses an explicit limit could be introduced. However, this would destroy some of the attractive features of the new scheme. An alternative would be a slight modification to some of the weighting factors. (author)

  8. PSOD: an interactive Fortran program to simulate the radiation dose response of membrane populations

    International Nuclear Information System (INIS)

    Perry, K.A.; Szekely, J.G.

    1982-04-01

    Program PSOD was written to simulate the distribution in responses of membrane populations subjected to random radiation doses and dose rates. It computes the response (damage) according to one of three formulas selected by the user, and outputs statistical results to the terminal. It will plot simulated dose- and response-frequency distributions in two or three dimensions. Doses and dose rates are selected from the log normal distribution; other distributions can be incorporated as the need arises. A true log normal curve with defined mean and standard deviation can also be generated. The purpose of this documentation is to provide a complete operating manual for the program. A user guide is available on-line after initiating a session of PSOD. Detailed examinations of the statistical validity of various steps have been included to aid future modifications and updating

  9. Maximally flat radiation patterns of a circular aperture

    Science.gov (United States)

    Minkovich, B. M.; Mints, M. Ia.

    1989-08-01

    The paper presents an explicit solution to the problems of maximizing the area utilization coefficient and of obtaining the best approximation (on the average) of a sectorial Pi-shaped radiation pattern of an antenna with a circular aperture when Butterworth conditions are imposed on the approximating pattern with the aim of flattening it. Constraints on the choice of admissible minimum and maximum antenna dimensions are determined which make possible the synthesis of maximally flat patterns with small sidelobes.

  10. On Maximally Dissipative Shock Waves in Nonlinear Elasticity

    OpenAIRE

    Knowles, James K.

    2010-01-01

    Shock waves in nonlinearly elastic solids are, in general, dissipative. We study the following question: among all plane shock waves that can propagate with a given speed in a given one-dimensional nonlinearly elastic bar, which one—if any—maximizes the rate of dissipation? We find that the answer to this question depends strongly on the qualitative nature of the stress-strain relation characteristic of the given material. When maximally dissipative shocks do occur, they propagate according t...

  11. The Large Margin Mechanism for Differentially Private Maximization

    OpenAIRE

    Chaudhuri, Kamalika; Hsu, Daniel; Song, Shuang

    2014-01-01

    A basic problem in the design of privacy-preserving algorithms is the private maximization problem: the goal is to pick an item from a universe that (approximately) maximizes a data-dependent function, all under the constraint of differential privacy. This problem has been used as a sub-routine in many privacy-preserving algorithms for statistics and machine-learning. Previous algorithms for this problem are either range-dependent---i.e., their utility diminishes with the size of the universe...

  12. Ultraviolet Radiation Induces Dose-Dependent Pigment Dispersion in Crustacean Chromatophores

    OpenAIRE

    Gouveia, Glauce Ribeiro; Lopes, Thaís Martins; Neves, Carla Amorim; Nery, Luiz Eduardo Maia; Trindade, Gilma Santos

    2004-01-01

    Pigment dispersion in chromatophores as a response to UV radiation was investigated in two species of crustaceans, the crab Chasmagnathus granulata and the shrimp Palaemonetes argentinus. Eyestalkless crabs and shrimps maintained on either a black or a white background were irradiated with different UV bands. In eyestalkless crabs the significant minimal effective dose inducing pigment dispersion was 0.42 J/cm2 for UVA and 2.15 J/cm2 for UVB. Maximal response was achieved with 10.0 J/cm...

  13. Enumerating all maximal frequent subtrees in collections of phylogenetic trees

    Science.gov (United States)

    2014-01-01

    Background A common problem in phylogenetic analysis is to identify frequent patterns in a collection of phylogenetic trees. The goal is, roughly, to find a subset of the species (taxa) on which all or some significant subset of the trees agree. One popular method to do so is through maximum agreement subtrees (MASTs). MASTs are also used, among other things, as a metric for comparing phylogenetic trees, computing congruence indices and to identify horizontal gene transfer events. Results We give algorithms and experimental results for two approaches to identify common patterns in a collection of phylogenetic trees, one based on agreement subtrees, called maximal agreement subtrees, the other on frequent subtrees, called maximal frequent subtrees. These approaches can return subtrees on larger sets of taxa than MASTs, and can reveal new common phylogenetic relationships not present in either MASTs or the majority rule tree (a popular consensus method). Our current implementation is available on the web at https://code.google.com/p/mfst-miner/. Conclusions Our computational results confirm that maximal agreement subtrees and all maximal frequent subtrees can reveal a more complete phylogenetic picture of the common patterns in collections of phylogenetic trees than maximum agreement subtrees; they are also often more resolved than the majority rule tree. Further, our experiments show that enumerating maximal frequent subtrees is considerably more practical than enumerating ordinary (not necessarily maximal) frequent subtrees. PMID:25061474

  14. Pace's Maxims for Homegrown Library Projects. Coming Full Circle

    Science.gov (United States)

    Pace, Andrew K.

    2005-01-01

    This article discusses six maxims by which to run library automation. The following maxims are discussed: (1) Solve only known problems; (2) Avoid changing data to fix display problems; (3) Aut viam inveniam aut faciam; (4) If you cannot make it yourself, buy something; (5) Kill the alligator closest to the boat; and (6) Just because yours is…

  15. Gravitational collapse of charged dust shell and maximal slicing condition

    International Nuclear Information System (INIS)

    Maeda, Keiichi

    1980-01-01

    The maximal slicing condition is a good time coordinate condition qualitatively when pursuing the gravitational collapse by the numerical calculation. The analytic solution of the gravitational collapse under the maximal slicing condition is given in the case of a spherical charged dust shell and the behavior of time slices with this coordinate condition is investigated. It is concluded that under the maximal slicing condition we can pursue the gravitational collapse until the radius of the shell decreases to about 0.7 x (the radius of the event horizon). (author)

  16. 327 Building liquid waste handling options modification project plan

    International Nuclear Information System (INIS)

    Ham, J.E.

    1998-01-01

    This report evaluates the modification options for handling radiological liquid waste (RLW) generated during decontamination and cleanout of the 327 Building. The overall objective of the 327 Facility Stabilization Project is to establish a passively safe and environmentally secure configuration of the 327 Facility. The issue of handling of RLW from the 327 Facility (assuming the 34O Facility is not available to accept the RLW) has been conceptually examined in at least two earlier engineering studies (Parsons 1997a and Hobart l997). Each study identified a similar preferred alternative that included modifying the 327 Facility RLWS handling systems to provide a truck load-out station, either within the confines of the facility or exterior to the facility. The alternatives also maximized the use of existing piping, tanks, instrumentation, controls and other features to minimize costs and physical changes. An issue discussed in each study involved the anticipated volume of the RLW stream. Estimates ranged between 113,550 and 387,500 liters in the earlier studies. During the development of the 324/327 Building Stabilization/Deactivation Project Management Plan, the lower estimate of approximately 113,550 liters was confirmed and has been adopted as the baseline for the 327 Facility RLW stream. The goal of this engineering study is to reevaluate the existing preferred alternative and select a new preferred alternative, if appropriate. Based on the new or confirmed preferred alternative, this study will also provide a conceptual design and cost estimate for required modifications to the 327 Facility to allow removal of RLWS and treatment of the RLW generated during deactivation

  17. A definition of maximal CP-violation

    International Nuclear Information System (INIS)

    Roos, M.

    1985-01-01

    The unitary matrix of quark flavour mixing is parametrized in a general way, permitting a mathematically natural definition of maximal CP violation. Present data turn out to violate this definition by 2-3 standard deviations. (orig.)

  18. Deconstructing facts and frames in energy research: Maxims for evaluating contentious problems

    International Nuclear Information System (INIS)

    Sovacool, Benjamin K.; Brown, Marilyn A.

    2015-01-01

    In this article, we argue that assumptions and values can play a combative, corrosive role in the generation of objective energy analysis. We then propose six maxims for energy analysts and researchers. Our maxim of information asks readers to keep up to date on trends in energy resources and technology. Our maxim of inclusivity asks readers to involve citizens and other public actors more in energy decisions. Our maxim of symmetry asks readers to keep their analysis of energy technologies centered always on both technology and society. Our maxim of reflexivity asks readers to be self-aware of one's assumptions. Our maxim of prudence asks readers to make energy decisions that are ethical or at least informed. Our maxim of agnosticism asks readers to look beyond a given energy technology to the services it provides and recognize that many systems can provide a desired service. We conclude that decisions in energy are justified by, if not predicated on, beliefs—beliefs which may or may not be supported by objective data, constantly blurring the line between fact, fiction, and frames. - Highlights: • Assumptions and values can play a combative, corrosive role in the generation of objective energy analysis. • Decisions in energy are justified by, if not predicated on, beliefs. • We propose six maxims for energy analysts and researcher.

  19. Maximal isometric strength of the cervical musculature in 100 healthy volunteers

    DEFF Research Database (Denmark)

    Jordan, A; Mehlsen, J; Bülow, P M

    1999-01-01

    A descriptive study involving maximal isometric strength measurements of the cervical musculature.......A descriptive study involving maximal isometric strength measurements of the cervical musculature....

  20. Optimization of an algorithm for 3D calculation of radiation dose distribution in heterogeneous media for use in radiotherapy planning

    International Nuclear Information System (INIS)

    Perles, L.A.; Chinellato, C.D.; Rocha, J.R.O.

    2001-01-01

    In this paper has been presented a modification of a algorithm for three-dimensional (3D) radiation dose distribution in heterogeneous media by convolutions. This modification has maintained good accordance between calculated and simulated data in EGS4 code. The results of algorithm have been compared with commercial program PLATO, where have been noticed inconsistency for equivalent density regions in a muscle-lung-muscle interface system

  1. Role of NO in adrenergic regulation of the heart after chronic gamma irradiation in 1 Gy dose

    International Nuclear Information System (INIS)

    Suvorova, T.A.; Lobanok, L.M.

    2005-01-01

    Chronic irradiation in 1 Gy dose significantly decreased adrenoreactivity of the heart. Modification of NO-mediated mechanisms plays an important role in radiation-induced changes of adrenergic control of heart functional activity and coronary flow. (authors)

  2. Dose conversion coefficients for high-energy photons, electrons, neutrons and protons

    International Nuclear Information System (INIS)

    Sakamoto, Yukio

    2005-01-01

    Dose conversion coefficients for photons, electrons and neutrons based on new ICRP recommendations were cited in the ICRP Publication 74, but the energy ranges of these data were limited and there are no data for high energy radiations produced in accelerator facilities. For the purpose of designing the high intensity proton accelerator facilities at JAERI, the dose evaluation code system of high energy radiations based on the HERMES code was developed and the dose conversion coefficients of effective dose were evaluated for photons, neutrons and protons up to 10 GeV, and electrons up to 100 GeV. The dose conversion coefficients of effective dose equivalent were also evaluated using quality factors to consider the consistency between radiation weighting factors and Q-L relationship. The effective dose conversion coefficients obtained in this work were in good agreement with those recently evaluated by using FLUKA code for photons and electrons with all energies, and neutrons and protons below 500 MeV. There were some discrepancy between two data owing to the difference of cross sections in the nuclear reaction models. The dose conversion coefficients of effective dose equivalents for high energy radiations based on Q-L relation in ICRP Publication 60 were evaluated only in this work. The previous comparison between effective dose and effective dose equivalent made it clear that the radiation weighting factors for high energy neutrons and protons were overestimated and the modification was required. (author)

  3. Carbon ion irradiation induced surface modification of polypropylene

    International Nuclear Information System (INIS)

    Saha, A.; Chakraborty, V.; Dutta, R.K.; Chintalapudi, S.N.

    2001-01-01

    Polypropylene was irradiated with 12 C ions of 3.6 and 5.4 MeV energies in the fluence range of 5x10 13 -5x10 14 ions/cm 2 using 3 MV tandem accelerator. Ion penetration was limited to a few microns and surface modifications were investigated by scanning electron microscopy. At the lowest ion fluence only blister formation of various sizes (1-6 μm) were observed, but at higher fluence (1x10 14 ions/cm 2 ) a three-dimensional network structure was found to form. A gradual degradation in the network structure was observed with further increase in the ion fluence. The dose dependence of the changes on surface morphology of polypropylene is discussed

  4. Carbon ion irradiation induced surface modification of polypropylene

    Energy Technology Data Exchange (ETDEWEB)

    Saha, A. E-mail: abhijit@alpha.iuc.res.in; Chakraborty, V.; Dutta, R.K.; Chintalapudi, S.N

    2001-12-01

    Polypropylene was irradiated with {sup 12}C ions of 3.6 and 5.4 MeV energies in the fluence range of 5x10{sup 13}-5x10{sup 14} ions/cm{sup 2} using 3 MV tandem accelerator. Ion penetration was limited to a few microns and surface modifications were investigated by scanning electron microscopy. At the lowest ion fluence only blister formation of various sizes (1-6 {mu}m) were observed, but at higher fluence (1x10{sup 14} ions/cm{sup 2}) a three-dimensional network structure was found to form. A gradual degradation in the network structure was observed with further increase in the ion fluence. The dose dependence of the changes on surface morphology of polypropylene is discussed.

  5. Nonadditive entropy maximization is inconsistent with Bayesian updating

    Science.gov (United States)

    Pressé, Steve

    2014-11-01

    The maximum entropy method—used to infer probabilistic models from data—is a special case of Bayes's model inference prescription which, in turn, is grounded in basic propositional logic. By contrast to the maximum entropy method, the compatibility of nonadditive entropy maximization with Bayes's model inference prescription has never been established. Here we demonstrate that nonadditive entropy maximization is incompatible with Bayesian updating and discuss the immediate implications of this finding. We focus our attention on special cases as illustrations.

  6. Les Ambivalences du Silence: Les "Maximes" de la Rochefoucauld Par Quatre Chemins

    Science.gov (United States)

    Turcat, Eric

    2012-01-01

    Maxims are famous for their moral pronouncements, yet La Rochefoucauld's "Maximes" (1678) have become infamous for offering little moral guidance. Morally ambivalent at best, the "Maximes" are also less known for their other forms of ambivalence, whether rhetorical, psychological, anthropological or linguistic. Such are…

  7. On the dose distribution in chicken carcasses irradiated with electron beams for control of pathogenic microorganisms

    International Nuclear Information System (INIS)

    Mager, B.; Ehlermann, D.A.E.

    1999-01-01

    Whole chicken carcasses packed as commercial batches (cardboard boxes containing 8-12 carcasses) can be irradiated with bremsstrahlung, which permits compliance with the required quotient of 2.0 of maximal and minimal radiation dose, so that this radiation treatment is equal to treatment with γ radiation from cobalt sources. (orig./CB) [de

  8. FLOUTS OF THE COOPERATIVE PRINCIPLE MAXIMS IN SBY’S PRESIDENTIAL INTERVIEWS

    Directory of Open Access Journals (Sweden)

    Fahrus Zaman Fadhly

    2012-12-01

    Full Text Available This paper analyzed the presidential interviews of the President of Republic of Indonesia, Susilo Bambang Yudoyono (SBY, based on Grice’s theory of the Cooperative Principles (CP. This study employed a qualitative research design and the data were three transcripts of interview discourse between SBY and eight Indonesian journalists obtained through the presidential official website: http://www.presidentsby.info. The research investigated the ways of SBY in flouting the CP maxims in his presidential interviews and the functions of the flouts were. The research revealed that SBY flouted all the CP maxims and the maxim of Quantity was frequently flouted. Meanwhile, there were four ways used by SBY in flouting the CP maxims, i.e. hedging, indirectness, open answer and detailed element. The function of the flouts, i.e. face saving acts (FSA, self-protection, awareness, politeness, interestingness, control of information, elaboration and ignorance. This research also revealed that CP maxims of Grice are not universal.

  9. Si-modified BHA bioceramics as a drug delivery system: Effect of modification method on structure and Rifampicin release

    Directory of Open Access Journals (Sweden)

    Olena Sych

    2015-09-01

    Full Text Available The work is devoted to the investigation of two different methods for introduction of silicon into ceramics, based on biogenic hydroxyapatite (BHA, on the structure and properties. Thus, porous samples of Si-modified BHA-based ceramics containing 2 or 5 wt.% Si were prepared by using two different precursors, i.e. polymethylsiloxane polyhydrate and fine silica (Aerosil® 200 powder. After the modification with silicon a marked change in the structure of material was observed. The use of Aerosil® 200 permits preparation of a more uniform structure as compared to that obtained by using polymethylsiloxane polyhydrate. However, the latter promotes an increase in both the porosity of samples (from 43 to 62.3% and their solubility in saline (from 0.18 to 1.20 wt.%/day as compared to the results obtained after the modification with Aerosil® 200, where maximal porosity and solubility were 48.5% and 0.23 wt.%/day, respectively. At the same time, the modification of hydroxyapatite ceramics with silicon using silica makes it possible to prolong release of a drug (e.g. Rifampicin out of sample pores for the first 24 h as compared to the ceramics modified with polymethylsiloxane polyhydrate.

  10. Evaluation of anti-hyperglycemic effect of Actinidia kolomikta (Maxim. etRur.) Maxim. root extract.

    Science.gov (United States)

    Hu, Xuansheng; Cheng, Delin; Wang, Linbo; Li, Shuhong; Wang, Yuepeng; Li, Kejuan; Yang, Yingnan; Zhang, Zhenya

    2015-05-01

    This study aimed to evaluate the anti-hyperglycemic effect of ethanol extract from Actinidia kolomikta (Maxim. etRur.) Maxim. root (AKE).An in vitro evaluation was performed by using rat intestinal α-glucosidase (maltase and sucrase), the key enzymes linked with type 2 diabetes. And an in vivo evaluation was also performed by loading maltose, sucrose, glucose to normal rats. As a result, AKE showed concentration-dependent inhibition effects on rat intestinal maltase and rat intestinal sucrase with IC(50) values of 1.83 and 1.03mg/mL, respectively. In normal rats, after loaded with maltose, sucrose and glucose, administration of AKE significantly reduced postprandial hyperglycemia, which is similar to acarbose used as an anti-diabetic drug. High contents of total phenolics (80.49 ± 0.05mg GAE/g extract) and total flavonoids (430.69 ± 0.91mg RE/g extract) were detected in AKE. In conclusion, AKE possessed anti-hyperglycemic effects and the possible mechanisms were associated with its inhibition on α-glucosidase and the improvement on insulin release and/or insulin sensitivity as well. The anti-hyperglycemic activity possessed by AKE maybe attributable to its high contents of phenolic and flavonoid compounds.

  11. Effect of fractionated X-ray doses on the hemogram and the protein formula of the mouse; Action de doses fractionnees de rayons X sur l'hemogramme et la formule proteique de la souris

    Energy Technology Data Exchange (ETDEWEB)

    Alix, D; Pierotti, Th [Commissariat a l' Energie Atomique, Grenoble (France). Centre d' Etudes Nucleaires

    1965-07-01

    The authors have studied the action of small doses of radiation on the system of mice. Irradiations was performed at doses of 50, 100, 150 or 200 R according to groups, either, as single dose or as fractionated doses. It was established that changes begin to become evident only after total exposure of 100 R. It occurs a decrease of cellular constituents and more often than not an increase of total proteins and {gamma}-globulins. (authors) [French] Les auteurs ont etudie l'action des faibles doses de radiation sur la souris. Des irradiations furent pratiquees a des doses totales de 50, 100, 150 ou 200 R suivant les lots, soit en dose unique, soit en doses fractionnees. Ils ont constate que les modifications ne commencent a apparaitre nettement qu'apres une exposition de 100 R au total. Elles se font dans le sens de la diminution pour les elements cellulaires, le plus souvent dans le sens de l'augmentation pour les proteines totales et les {gamma}-globulines. (auteurs)

  12. Bipartite Bell Inequality and Maximal Violation

    International Nuclear Information System (INIS)

    Li Ming; Fei Shaoming; Li-Jost Xian-Qing

    2011-01-01

    We present new bell inequalities for arbitrary dimensional bipartite quantum systems. The maximal violation of the inequalities is computed. The Bell inequality is capable of detecting quantum entanglement of both pure and mixed quantum states more effectively. (general)

  13. Maximally efficient protocols for direct secure quantum communication

    Energy Technology Data Exchange (ETDEWEB)

    Banerjee, Anindita [Department of Physics and Materials Science Engineering, Jaypee Institute of Information Technology, A-10, Sector-62, Noida, UP-201307 (India); Department of Physics and Center for Astroparticle Physics and Space Science, Bose Institute, Block EN, Sector V, Kolkata 700091 (India); Pathak, Anirban, E-mail: anirban.pathak@jiit.ac.in [Department of Physics and Materials Science Engineering, Jaypee Institute of Information Technology, A-10, Sector-62, Noida, UP-201307 (India); RCPTM, Joint Laboratory of Optics of Palacky University and Institute of Physics of Academy of Science of the Czech Republic, Faculty of Science, Palacky University, 17. Listopadu 12, 77146 Olomouc (Czech Republic)

    2012-10-01

    Two protocols for deterministic secure quantum communication (DSQC) using GHZ-like states have been proposed. It is shown that one of these protocols is maximally efficient and that can be modified to an equivalent protocol of quantum secure direct communication (QSDC). Security and efficiency of the proposed protocols are analyzed and compared. It is shown that dense coding is sufficient but not essential for DSQC and QSDC protocols. Maximally efficient QSDC protocols are shown to be more efficient than their DSQC counterparts. This additional efficiency arises at the cost of message transmission rate. -- Highlights: ► Two protocols for deterministic secure quantum communication (DSQC) are proposed. ► One of the above protocols is maximally efficient. ► It is modified to an equivalent protocol of quantum secure direct communication (QSDC). ► It is shown that dense coding is sufficient but not essential for DSQC and QSDC protocols. ► Efficient QSDC protocols are always more efficient than their DSQC counterparts.

  14. Chamaebatiaria millefolium (Torr.) Maxim.: fernbush

    Science.gov (United States)

    Nancy L. Shaw; Emerenciana G. Hurd

    2008-01-01

    Fernbush - Chamaebatiaria millefolium (Torr.) Maxim. - the only species in its genus, is endemic to the Great Basin, Colorado Plateau, and adjacent areas of the western United States. It is an upright, generally multistemmed, sweetly aromatic shrub 0.3 to 2 m tall. Bark of young branches is brown and becomes smooth and gray with age. Leaves are leathery, alternate,...

  15. Generalized Yosida Approximations Based on Relatively A-Maximal m-Relaxed Monotonicity Frameworks

    Directory of Open Access Journals (Sweden)

    Heng-you Lan

    2013-01-01

    Full Text Available We introduce and study a new notion of relatively A-maximal m-relaxed monotonicity framework and discuss some properties of a new class of generalized relatively resolvent operator associated with the relatively A-maximal m-relaxed monotone operator and the new generalized Yosida approximations based on relatively A-maximal m-relaxed monotonicity framework. Furthermore, we give some remarks to show that the theory of the new generalized relatively resolvent operator and Yosida approximations associated with relatively A-maximal m-relaxed monotone operators generalizes most of the existing notions on (relatively maximal monotone mappings in Hilbert as well as Banach space and can be applied to study variational inclusion problems and first-order evolution equations as well as evolution inclusions.

  16. Full system decontamination (FSD) for sustainable dose reduction

    International Nuclear Information System (INIS)

    Stiepani, Christoph; Sempere-Belda, Luis; Topf, Christian; Basu, Ashim

    2012-09-01

    Nuclear power plants experience an increase in dose rates during operation due to the build-up of the activity inventory. The activity build-up is influenced by the construction materials, past and present water chemistries, and the individual operating history of the plant. Depending on these factors the dose levels in an operating plant may reach a point in which concrete actions to reduce the overall radiation exposure become necessary. In the past dose reduction plans were performed, based on - Modification in coolant water chemistry - Substitution of Cobalt containing materials - Outage optimization program - Installation of permanent shielding - Decontamination The dose rate reduction took several years and today a stagnation of further dose rate reduction can be seen. Therefore AREVA has developed the Concept for Sustainable Dose Reduction in Operating BWRs and PWRs. This is a program of joint corrective measures to minimize dose levels rapidly and keep them low for continued operation. It can be applied in plants from all constructors and designs. The concept is based fully on the application of proven technologies, including: - Full System Decontamination with AREVA's decontamination process HP/CORD UV to minimize the activity inventory - The formation of new, very stable protective oxides on the system surfaces including injection of depleted zinc - Introduction of advanced water chemistry for maintaining the low dose levels achieved during ongoing operation The implementation of this program is particularly interesting for plants with a long operation history, especially when considering life extension. The latest application was performed successfully at the German PWR Grafenrheinfeld in 2010. In this paper the concept for sustainable dose reduction will be outlined and the site application detailed and the achieved results at PWR Grafenrheinfeld will be described. The recontamination after one cycle will be outlined in a second paper. (authors)

  17. Study of dose modification in skin cancers induced by the kind of bolus used - Bibliography

    International Nuclear Information System (INIS)

    Camilleri, Jeremy

    2011-01-01

    As tumour irradiation modalities differ from one pathology to another, and are even proper to each pathology (they depend on tumour nature, histology, size, location, and so on), but as therapeutic objectives remain unchanged (to deliver the prescribed dose to the target-volume with the highest possible precision while preserving as much as possible sane tissues as well as neighbouring organs at risk), this bibliographical study aims, on the one hand, at quantifying the dose variation generated by heterogeneous structures crossed by the electron beam, and on the other hand, at optimising the use of boluses during surface irradiations, notably in the case of skin cancers. The author addresses therapeutic indications of irradiation of skin cancers and of thoracic wall for which the application of a bolus is required, and then the associated irradiation techniques as well as bolus characteristics

  18. Characterisation and Radiation Modification of Carrageenan in the Solid State

    International Nuclear Information System (INIS)

    Gulrez, S.; Al-Assaf, S.; Phillips, G.O.

    2010-01-01

    This study reports the modification of kappa-carrageenan in the solid state using gamma radiation (in the dose range of 1-25kGy) in the presence of unsaturated alkyne gas. The results showed maximum production of hydrogel at 5kGy with nearly 80% of starting material being converted to hydrogel form in the absence of a gellin agent. Higher irradiation doses at 25kGy resulted in reducing the hydrogel proportion to ~40% due to degradation. The molecular weight and distribution was determined by GPC-MALLS and the results showed a decrease in the mass recovery and molecular weight of the soluble fraction at 60C. The molecular weight results were in agreement with hydrogel data determined from the filtration method. There was an optimum increase in the viscosity, elasticity and mechanical strength at 5kGy which was followed by a decrease in the gel strength at higher doses (25kGy). Our study demonstrates the potential production of novel hydrogel based carrageenan obtained by irradiation in the absence of metal ions with possible new applications. A mechanism for the radiation induced cross-linking to produce superhelical aggregates in the absence of a gelling agent is proposed. (author)

  19. Study of Textile Surface Characteristic Modification by Using Electron Beam Radiation

    International Nuclear Information System (INIS)

    Iswani Gitawati; Rany Saptaaji

    2007-01-01

    The success of accelerator technology application in various field of industry, medical and pharmacy, environment, agricultural, food increase each year as the increasing of people needs, not excepted for surface treatment of fibers and textiles in textile industry. This writing aim is to asses the application of electron beam accelerator for textile surface treatment on finishing step. Surface treatment was done with electron beam low energy (100 - 500 keV), and because of its low penetration it was suitable used to gain the improvement of chemical, physical and mechanical properties of textile surface such as adhesion, wettability, printability, dyes-intake, crease recovery, wrinkle-resistance, flammability, abrasion resistance, soil and stain release to get better result. Modification of fibers and textiles surface properties on finishing process can be caused by crosslinking, grafting and degradation reactions. The assesment results showed that the greatest impact on commercial application of radiation in textiles were crease recovery and surface modification of wetting properties (soil and stain release). The radiation dose used for those purposes were 5 - 50 kGy. The bach process of graft textiles surface modification before and after irradiation by Co-60 source (gamma energies of 1.33 and 1.17 MeV) and continue process by electron beam were presented. The assesment results were reported in this paper. (author)

  20. Mutually Unbiased Maximally Entangled Bases for the Bipartite System Cd⊗ C^{dk}

    Science.gov (United States)

    Nan, Hua; Tao, Yuan-Hong; Wang, Tian-Jiao; Zhang, Jun

    2016-10-01

    The construction of maximally entangled bases for the bipartite system Cd⊗ Cd is discussed firstly, and some mutually unbiased bases with maximally entangled bases are given, where 2≤ d≤5. Moreover, we study a systematic way of constructing mutually unbiased maximally entangled bases for the bipartite system Cd⊗ C^{dk}.

  1. Sensitization of rat 9L gliosarcoma cells to low dose rate irradiation by long duration 41 degrees C hyperthermia.

    Science.gov (United States)

    Armour, E P; Wang, Z H; Corry, P M; Martinez, A

    1991-06-15

    Modification of survival by long duration, 41 degrees C hyperthermia in combination with low dose rate radiation (0.5 Gy/h) was determined in rat 9L gliosarcoma cells. Cells were exposed to radiation in a manner that simulated continuous irradiation at a dose rate relevant to clinical brachytherapy. High dose rate X-irradiation was fractionated in 1.0-Gy fractions at 2-h intervals (FLDRI). Previous studies had demonstrated that 9L cells exposed to FLDRI with these parameters have survival characteristics that are equivalent to continuous low dose rate irradiation. Cells exposed to 41 degrees C throughout FLDRI were sensitized significantly (thermal enhancement ratio of 2.07) compared with cells irradiated at 37 degrees C. Incubation for 24 h at 41 degrees C before and/or after FLDRI at either 37 degrees C or 41 degrees C did not increase the slope of the radiation survival curves but did reduce the shoulder. Similarly, heating at 43 degrees C for 30 or 60 min before and/or after irradiation at 0.5 Gy/h also did not enhance cell sensitivity. Survival of cells after irradiation at high dose rate (60 Gy/h) was independent of the temperature during irradiation. Preheat at 41 degrees C for 24 h did not sensitize cells to high dose rate irradiation by increasing the slope of the survival curve, although a loss of shoulder was observed. Sensitization of cells heated at 43 degrees C for 30 or 60 min before high dose rate irradiation was expressed as classical slope modification. Our results demonstrate that 41 degrees C heating during FLDRI greatly sensitizes cells to radiation-induced killing for exposure durations up to 36 h. Heating 9L cells at 41 degrees C or 43 degrees C adjacent to FLDRI at 0.5 Gy/h resulted in no additional enhancement of terminal sensitivity, although shoulder modification was observed. The sensitization by simultaneous heating described above occurred even though thermotolerance developed during extended incubation at 41 degrees C. These in vitro

  2. Maximal near-field radiative heat transfer between two plates

    Science.gov (United States)

    Nefzaoui, Elyes; Ezzahri, Younès; Drévillon, Jérémie; Joulain, Karl

    2013-09-01

    Near-field radiative transfer is a promising way to significantly and simultaneously enhance both thermo-photovoltaic (TPV) devices power densities and efficiencies. A parametric study of Drude and Lorentz models performances in maximizing near-field radiative heat transfer between two semi-infinite planes separated by nanometric distances at room temperature is presented in this paper. Optimal parameters of these models that provide optical properties maximizing the radiative heat flux are reported and compared to real materials usually considered in similar studies, silicon carbide and heavily doped silicon in this case. Results are obtained by exact and approximate (in the extreme near-field regime and the electrostatic limit hypothesis) calculations. The two methods are compared in terms of accuracy and CPU resources consumption. Their differences are explained according to a mesoscopic description of nearfield radiative heat transfer. Finally, the frequently assumed hypothesis which states a maximal radiative heat transfer when the two semi-infinite planes are of identical materials is numerically confirmed. Its subsequent practical constraints are then discussed. Presented results enlighten relevant paths to follow in order to choose or design materials maximizing nano-TPV devices performances.

  3. Genetic modification and genetic determinism

    Science.gov (United States)

    Resnik, David B; Vorhaus, Daniel B

    2006-01-01

    In this article we examine four objections to the genetic modification of human beings: the freedom argument, the giftedness argument, the authenticity argument, and the uniqueness argument. We then demonstrate that each of these arguments against genetic modification assumes a strong version of genetic determinism. Since these strong deterministic assumptions are false, the arguments against genetic modification, which assume and depend upon these assumptions, are therefore unsound. Serious discussion of the morality of genetic modification, and the development of sound science policy, should be driven by arguments that address the actual consequences of genetic modification for individuals and society, not by ones propped up by false or misleading biological assumptions. PMID:16800884

  4. Genetic modification and genetic determinism

    Directory of Open Access Journals (Sweden)

    Vorhaus Daniel B

    2006-06-01

    Full Text Available Abstract In this article we examine four objections to the genetic modification of human beings: the freedom argument, the giftedness argument, the authenticity argument, and the uniqueness argument. We then demonstrate that each of these arguments against genetic modification assumes a strong version of genetic determinism. Since these strong deterministic assumptions are false, the arguments against genetic modification, which assume and depend upon these assumptions, are therefore unsound. Serious discussion of the morality of genetic modification, and the development of sound science policy, should be driven by arguments that address the actual consequences of genetic modification for individuals and society, not by ones propped up by false or misleading biological assumptions.

  5. Accommodating for plant modifications

    International Nuclear Information System (INIS)

    Weirich, P.H.

    1977-01-01

    Modification to a nuclear power plant may have different causes: 1) new instructions by the authorities; 2) changes of the marginal conditions on the construction site; 3) progress in the technological development. - Examples from different plants are supposed to demonstrate how such changes influence the planning or the construction and how they are integrated in the process of preparation. A distinction can be made between modifications before the completion of the submission of the order, during the phase of preparatory planning and during the construction phase. Of great importance are especially modifications made after the beginning of the construction works, since, in general, there is little scope for technical modifications and since consequences for the time schedule are to be expected. (orig.) [de

  6. Radioecology of and radiation dose from Dutch waste gypsum released into the environment

    International Nuclear Information System (INIS)

    Koster, H.W.; Weers, A.W. van; Netherlands Energy Research Foundation, Petten)

    1985-11-01

    The Dutch industries release 9 kinds of waste gypsum, 90% of the total quantity is phosphogypsum. Only waste gypsums from the phosphate industries show increased radioactivity, the strongest in phosphogypsum. All phosphogypsum, 2 Tg.a -1 , is disposed of into the Rhine at Rotterdam. This leads to an increase of radionuclides, from the U-238 chain, along the Dutch coast. The calculated increase of activity concentrations in sea food causes an increase of the individual radiation dose of maximal 150 μSv.a -1 and of the Dutch population dose of 170 manSv.a -1 . Stacking of the phosphogypsum would result in a dose increase of one order of magnitude lower. The need for environmental disposal or stacking of at least the fine and coarse fractions of the phosphogypsum, which are difficult to recycle, will remain. (Auth.)

  7. Maximally entangled mixed states of two atoms trapped inside an optical cavity

    International Nuclear Information System (INIS)

    Li Shangbin; Xu Jingbo

    2009-01-01

    In some off-resonant cases, the reduced density matrix of two atoms symmetrically coupled with an optical cavity can very approximately approach maximally entangled mixed states or maximal Bell violation mixed states in their evolution. The influence of a phase decoherence on the generation of a maximally entangled mixed state is also discussed

  8. Application of the luminescence single-aliquot technique for dose estimation in the Marmara Sea

    International Nuclear Information System (INIS)

    Tanir, Guenes; Sencan, Emine; Boeluekdemir, M. Hicabi; Tuerkoez, M. Burak; Tel, Eyuep

    2005-01-01

    The aim of this study is to obtain the equivalent dose, which is the important quantity for all the studies related to the use of luminescence in dating sediments. Recent advances in luminescence dating have led to increasing application of the technique to sediment from the depositional environmental samples. The sample used in this study is the active main fault sample that was collected from the Sea of Marmara in NW Turkey. Equivalent dose was measured using both the multiple-aliquots and the single-aliquot techniques. In this study single aliquot regeneration on additive dose (SARA) procedure was also used. The result obtained was not in agreement with the results evaluated from the multiple-aliquots procedure. So a simple modification was suggested for SARA procedure. In our modified procedure the calculated dose (D) values were obtained by using the additive dose protocol instead of regeneration protocol

  9. Application of Key Events Dose Response Framework to defining the upper intake level of leucine in young men.

    Science.gov (United States)

    Pencharz, Paul B; Russell, Robert M

    2012-12-01

    Leucine is sold in large doses in health food stores and is ingested by weight-training athletes. The safety of ingestion of large doses of leucine is unknown. Before designing chronic high-dose leucine supplementation experiments, we decided to determine the effect of graded doses of leucine in healthy participants. The Key Events Dose Response Framework is an organizational and analytical framework that dissects the various biologic steps (key events) that occur between exposure to a substance and an eventual adverse effect. Each biologic event is looked at for its unique dose-response characteristics. For nutrients, there are a number of biologic homeostatic mechanisms that work to keep circulating/tissue levels in a safe, nontoxic range. If a response mechanism at a particular key event is especially vulnerable and easily overwhelmed, this is known as a determining event, because this event drives the overall slope or shape of the dose-response relationship. In this paper, the Key Events Dose Framework has been applied to the problem of leucine toxicity and leucine's tolerable upper level. After analyzing the experimental data vis a vis key events for leucine leading to toxicity, it became evident that the rate of leucine oxidation was the determining event. A dose-response study has been conducted to graded intakes of leucine in healthy human adult male volunteers. All participants were started at the mean requirement level of leucine [50 mg/(kg · d)] and the highest leucine intake was 1250 mg/( kg · d), which is 25 times the mean requirement. No gut intolerance was seen. Blood glucose fell progressively but remained within normal values without any changes in plasma insulin. Maximal leucine oxidation levels occurred at an intake of 550 mg leucine/( kg · d), after which plasma leucine progressively increased and plasma ammonia also increased in response to leucine intakes >500 mg/( kg · d). Thus, the "key determining event" appears to be when the

  10. IIB solutions with N>28 Killing spinors are maximally supersymmetric

    International Nuclear Information System (INIS)

    Gran, U.; Gutowski, J.; Papadopoulos, G.; Roest, D.

    2007-01-01

    We show that all IIB supergravity backgrounds which admit more than 28 Killing spinors are maximally supersymmetric. In particular, we find that for all N>28 backgrounds the supercovariant curvature vanishes, and that the quotients of maximally supersymmetric backgrounds either preserve all 32 or N<29 supersymmetries

  11. Acrolein, A Reactive Product of Lipid Peroxidation, Induces Oxidative Modification of Cytochrome c

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Jung Hoon [Cheongju Univ., Cheongju (Korea, Republic of)

    2013-11-15

    Acrolein (ACR) is a well-known carbonyl toxin produced by lipid peroxidation of polyunsaturated fatty acids, which is involved in the pathogenesis of neurodegenerative disorders such as Alzheimer's disease (AD). In Alzheimer's brain, ACR was found to be elevated in hippocampus and temporal cortex where oxidative stress is high. In this study, we evaluated oxidative modification of cytochrome c occurring after incubation with ACR. When cytochrome c was incubated with ACR, protein aggregation increased in a dose-dependent manner. The formation of carbonyl compounds and the release of iron were obtained in ACR-treated cytochrome c. Reactive oxygen species scavengers and iron specific chelator inhibited the ACR-mediated cytochrome c modification and carbonyl compound formation. Our data demonstrate that oxidative damage of cytochrome c by ACR might induce disruption of cyotochrome c structure and iron mishandling as a contributing factor to the pathology of AD.

  12. Acrolein, A Reactive Product of Lipid Peroxidation, Induces Oxidative Modification of Cytochrome c

    International Nuclear Information System (INIS)

    Kang, Jung Hoon

    2013-01-01

    Acrolein (ACR) is a well-known carbonyl toxin produced by lipid peroxidation of polyunsaturated fatty acids, which is involved in the pathogenesis of neurodegenerative disorders such as Alzheimer's disease (AD). In Alzheimer's brain, ACR was found to be elevated in hippocampus and temporal cortex where oxidative stress is high. In this study, we evaluated oxidative modification of cytochrome c occurring after incubation with ACR. When cytochrome c was incubated with ACR, protein aggregation increased in a dose-dependent manner. The formation of carbonyl compounds and the release of iron were obtained in ACR-treated cytochrome c. Reactive oxygen species scavengers and iron specific chelator inhibited the ACR-mediated cytochrome c modification and carbonyl compound formation. Our data demonstrate that oxidative damage of cytochrome c by ACR might induce disruption of cyotochrome c structure and iron mishandling as a contributing factor to the pathology of AD

  13. Biomaterials modification by ion beam

    International Nuclear Information System (INIS)

    Zhang Tonghe; Yi Zhongzhen; Zhang Xu; Wu Yuguang

    2001-01-01

    Ion beam technology is one of best ways for the modification of biomaterials. The results of ion beam modification of biomaterials are given. The method and results of improved biocompatibility are indicated by ion beam technology. The future development of ion beam modification of biomaterials is discussed

  14. Comparative analysis of collective doses received since 1976 at the Ardennes nuclear power plant

    International Nuclear Information System (INIS)

    Aye, Louis

    1980-01-01

    The analysis of the collective doses at the Centrale nucleaire des Ardennes povides valuable data about the origin of exposures in P.W.R. reactors and their evolution regarding the increase of activity of the circuits after more than 10 years of operation. The investigations led for most of the works since 1976 reveals that, in some cases, the use of sophisticated implements combined with modifications of equipments and procedures may bring appreciable savings on doses during normal operation as well as maintenance and refuelings shut-down. However, the study gives the 'reasonably achievable' limits than can be aimed in a plant on operation, the doses resulting mainly from problems that should be taken into account at design [fr

  15. Boron dose determination for BNCT using Fricke and EPR dosimetry

    International Nuclear Information System (INIS)

    Wielopolski, L.; Ciesielski, B.

    1995-01-01

    In Boron Neutron Capture Therapy (BNCT) the dominant dose delivered to the tumor is due to α and 7 Li charged particles resulting from a neutron capture by 10 B and is referred to herein as the boron dose. Boron dose is directly attributable to the following two independent factors, one boron concentration and the neutron capture energy dependent cross section of boron, and two the energy spectrum of the neutrons that interact with boron. The neutron energy distribution at a given point is dictated by the incident neutron energy distribution, the depth in tissue, geometrical factors such as beam size and patient's dimensions. To account for these factors can be accommodated by using Monte Carlo theoretical simulations. However, in conventional experimental BNCT dosimetry, e.g., using TLDs or ionization chambers, it is only possible to estimate the boron dose. To overcome some of the limitations in the conventional dosimetry, modifications in ferrous sulfate dosimetry (Fricke) and Electron Paramagnetic Resonance (EPR) dosimetry in alanine, enable to measure specifically boron dose in a mixed gamma neutron radiation fields. The boron dose, in either of the dosimeters, is obtained as a difference between measurements with boronated and unboronated dosimeters. Since boron participates directly in the measurements, the boron dosimetry reflects the true contribution, integral of the neutron energy spectrum with boron cross section, of the boron dose to the total dose. Both methods are well established and used extensively in dosimetry, they are presented briefly here

  16. Suboptimal Antituberculosis Drug Concentrations and Outcomes in Small and HIV-Coinfected Children in India: Recommendations for Dose Modifications.

    Science.gov (United States)

    Guiastrennec, Benjamin; Ramachandran, Geetha; Karlsson, Mats O; Kumar, A K Hemanth; Bhavani, Perumal Kannabiran; Gangadevi, N Poorana; Swaminathan, Soumya; Gupta, Amita; Dooley, Kelly E; Savic, Radojka M

    2017-12-16

    This work aimed to evaluate the once-daily antituberculosis treatment as recommended by the new Indian pediatric guidelines. Isoniazid, rifampin, and pyrazinamide concentration-time profiles and treatment outcome were obtained from 161 Indian children with drug-sensitive tuberculosis undergoing thrice-weekly dosing as per previous Indian pediatric guidelines. The exposure-response relationships were established using a population pharmacokinetic-pharmacodynamic approach. Rifampin exposure was identified as the unique predictor of treatment outcome. Consequently, children with low body weight (4-7 kg) and/or HIV infection, who displayed the lowest rifampin exposure, were associated with the highest probability of unfavorable treatment (therapy failure, death) outcome (P unfavorable ). Model-based simulation of optimized (P unfavorable ≤ 5%) rifampin once-daily doses were suggested per treatment weight band and HIV coinfection status (33% and 190% dose increase, respectively, from the new Indian guidelines). The established dose-exposure-response relationship could be pivotal in the development of future pediatric tuberculosis treatment guidelines. © 2017, The Authors Clinical Pharmacology & Therapeutics published by Wiley Periodicals, Inc. on behalf of American Society for Clinical Pharmacology and Therapeutics.

  17. Mammography-oncogenecity at low doses

    International Nuclear Information System (INIS)

    Heyes, G J; Mill, A J; Charles, M W

    2009-01-01

    Controversy exists regarding the biological effectiveness of low energy x-rays used for mammography breast screening. Recent radiobiology studies have provided compelling evidence that these low energy x-rays may be 4.42 ± 2.02 times more effective in causing mutational damage than higher energy x-rays. These data include a study involving in vitro irradiation of a human cell line using a mammography x-ray source and a high energy source which matches the spectrum of radiation observed in survivors from the Hiroshima atomic bomb. Current radiation risk estimates rely heavily on data from the atomic bomb survivors, and a direct comparison between the diagnostic energies used in the UK breast screening programme and those used for risk estimates can now be made. Evidence highlighting the increase in relative biological effectiveness (RBE) of mammography x-rays to a range of x-ray energies implies that the risks of radiation-induced breast cancers for mammography x-rays are potentially underestimated by a factor of four. A pooled analysis of three measurements gives a maximal RBE (for malignant transformation of human cells in vitro) of 4.02 ± 0.72 for 29 kVp (peak accelerating voltage) x-rays compared to high energy electrons and higher energy x-rays. For the majority of women in the UK NHS breast screening programme, it is shown that the benefit safely exceeds the risk of possible cancer induction even when this higher biological effectiveness factor is applied. The risk/benefit analysis, however, implies the need for caution for women screened under the age of 50, and particularly for those with a family history (and therefore a likely genetic susceptibility) of breast cancer. In vitro radiobiological data are generally acquired at high doses, and there are different extrapolation mechanisms to the low doses seen clinically. Recent low dose in vitro data have indicated a potential suppressive effect at very low dose rates and doses. Whilst mammography is a low

  18. Safety of modifications at nuclear power plants - the role of minor modifications and human and organisational factors

    International Nuclear Information System (INIS)

    2005-01-01

    Operating experience repeatedly shows that changes and modifications at nuclear power plants (NPPs) may lead to safety significant events. At the same time, modifications are necessary to ensure a safe and economic functioning of the NPPs. To ensure safety in all plant configurations it is important that modification processes are given proper attention both by the utilities and the regulators. The operability, maintainability and testability of every modification should be thoroughly assessed from different points of view to ensure that no safety problems are introduced. The OECD/NEA Committee on Safety of Nuclear Installations (CSNI) has recently addressed the issue of modifications by organising a 'Workshop on Modifications at Nuclear Power Plants Operating Experience, Safety Significance and Role of Human Factors'. This workshop was undertaken as a joint effort of the Working Group on Operating Experience (WGOE) and the Special Experts Group on Human and Organisational Factors (SEGHOF), and it was held at the OECD Headquarters in Paris on October 6 to 8, 2003. The initiative to organise the workshop was taken by the WGOE and the SEGHOF based on findings from events and incidents due to modifications at nuclear power plants in the world and weaknesses experienced in modification processes. During the workshop, the WGOE focused on the theme of 'Minor Modifications and their Safety Significance', while the SEGHOF focused on the topic 'Human and Organisational Factors in NPP Modifications'. This report is based on material collected before the workshop, the workshop proceedings, discussions of the group of experts responsible for the arrangement of the workshop, and additional material collected by a consultant. The workshop was preceded by extensive preparations, which included collection of national surveys in response to questionnaires on modifications at the NPPs. Not all of these surveys were available at the workshop, but their findings have now been included

  19. Modification of JRR-2

    International Nuclear Information System (INIS)

    Miyasaka, Yasuhiko

    1978-01-01

    This report gives an outline of some of the main modifications carried out around the Reactor Core on the Research Reactor JRR-2, at the Tokai Research Establishment of JAERI. The JRR-2 was shut down in December 1973, to improve it in heavy water leakage from the metal packing between core tank and support ring, corrosion of the lower shielding plug, and fault in the control-rod mechanism. Main modifications were a standing seal weld at the support ring to stop heavy water leakage, replacement of the reactor top shield and improvement of the helium system. The control-rod assemblies and the refueling devices were replaced by the newly designed ones also. In addition to the modification plan, the irradiated air exhaust system was improved to reduce radioactive argon gas release through the stack. Works were completed successfully in September 1975. But a light water leakage occurred at the stand pipe below the light water tank on November 11, 1975, which was repaired in about 4 months. When considering the operation of above 5,000 hours after the modification, however, the quality of the modification work may be said to be quite satisfactory. The present report in which works to the completion are described may be valuable as a record of reactor modification which is a new experience at JAERI. (auth.)

  20. Violations of Grice`s Maxims in The Prince and the Pauper Movie

    Directory of Open Access Journals (Sweden)

    Antonius Waget

    2016-12-01

    Full Text Available Proper responses must be provided interlocutors to make onversation productive and meaningful. However, interlocutors do not always provide proper responses because they do not even know conversation rules. Grice coins 4 maxims as general rules to govern daily conversation. The maxims are Quantity, Quality, Relevance, and Manner. Conversation occurs in the real daily interaction also in arts including movies. The Prince and the Pauper movie is one of the media for human daily conversation. Some parts of the movie contains violations of Grice`s maxims by the characters. Based on this background, the writer intends to explore violations ofGrice’s maxims in the movie and analyze the purposes of the violations. To achieve these objectives, the writer formulates two research problems: (1 Which of Grice`s maxims are violated by the addressees in The Prince and the Pauper movie? (2 For what purposes do the addressees violate the maxims? The base of this research is a movie script as document. Thus, the writer uses document analysis as the method of this research. Grounded on the analysis, the writer finds that the characters, especially Prince, Tom Canty, King, and the Earl of Hertford in the movie dialogues violate the four of Grice`s maxims. When failing to provide sufficient information, telling lie to their addressers, providing irrelevant glosses, and failing to be true, brief, univocal, and orderly, they respectively violate maxims of Quantity, Quality, Relevance, and Manner. Moreover, the writer finds that the characters violate the maxims in order to mislead the counterparts, be polite, save face, avoid discussion, and communicate self-interest.   DOI: https://doi.org/10.24071/llt.2015.180101

  1. Modification of mutation process in radiated seeds oat (Avena sativa L.) and barley (Hordeum vulgare L.)

    International Nuclear Information System (INIS)

    Shishlov, M.P.

    2007-01-01

    The results of a long-term investigations for experimental mutagenesis of oats and barley are reported in the article. It was found the problem of modification of a mutant process to spread spectrum and increase the general induction frequency and display of macro- and micro mutations. Application as modificators of salts the heavy metals, inhibitors of nuclein, protein synthesis and energy returned processes and also doses spectrum and its strength of gamma-radiation and ultrasound allowed to increase the general frequency of mutant induction of barley and oats on 1-2 order. On the base of evaluation of correlative links between the attributes variability in M1 and M2 generations it was formulated a conception of guarantied creation of mutant forms of the grain crops. (authors)

  2. Maximization of Tsallis entropy in the combinatorial formulation

    International Nuclear Information System (INIS)

    Suyari, Hiroki

    2010-01-01

    This paper presents the mathematical reformulation for maximization of Tsallis entropy S q in the combinatorial sense. More concretely, we generalize the original derivation of Maxwell-Boltzmann distribution law to Tsallis statistics by means of the corresponding generalized multinomial coefficient. Our results reveal that maximization of S 2-q under the usual expectation or S q under q-average using the escort expectation are naturally derived from the combinatorial formulations for Tsallis statistics with respective combinatorial dualities, that is, one for additive duality and the other for multiplicative duality.

  3. Sub-therapeutic doses of fluvastatin and valsartan are more effective than therapeutic doses in providing beneficial cardiovascular pleiotropic effects in rats: A proof of concept study.

    Science.gov (United States)

    Janić, Miodrag; Lunder, Mojca; France Štiglic, Alenka; Jerin, Aleš; Skitek, Milan; Černe, Darko; Marc, Janja; Drevenšek, Gorazd; Šabovič, Mišo

    2017-12-01

    Statins and sartans can, in therapeutic doses, induce pleiotropic cardiovascular effects. Similar has recently been shown also for sub-therapeutic doses. We thus explored and compared the cardiovascular pleiotropic efficacy of sub-therapeutic vs. therapeutic doses. Wistar rats were randomly divided into 7 groups receiving fluvastatin, valsartan and their combination in sub-therapeutic and therapeutic doses, or saline. After 6weeks, the animals were euthanised, their hearts and thoracic aortas isolated, and blood samples taken. Endothelium-dependent relaxation of the thoracic aortae and ischaemic-reperfusion injury of the isolated hearts were assessed along with the related serum parameters and genes expression. Fluvastatin and valsartan alone or in combination were significantly more effective in sub-therapeutic than therapeutic doses. The sub-therapeutic combination greatly increased thoracic aorta endothelium-dependent relaxation and maximally protected the isolated hearts against ischaemia-reperfusion injury and was thus most effective. Beneficial effects were accompanied by increased levels of nitric oxide (NO) and decreased levels of asymmetric dimethylarginine (ADMA) in the serum (again prominently induced by the sub-therapeutic combination). Furthermore, nitric oxide synthase 3 (NOS3) and endothelin receptor type A (EDNRA) genes expression increased, but only in both combination groups and without significant differences between them. In the therapeutic dose groups, fluvastatin and valsartan decreased cholesterol values and systolic blood pressure. Sub-therapeutic doses of fluvastatin and valsartan are more effective in expressing cardiovascular pleiotropic effects than therapeutic doses of fluvastatin and/or valsartan. These results could be of significant clinical relevance. Copyright © 2017 Elsevier Inc. All rights reserved.

  4. Population dose commitments due to radioactive releases from nuclear power plant sites in 1987

    International Nuclear Information System (INIS)

    Baker, D.A.

    1990-08-01

    Population radiation dose commitments have been estimated from reported radionuclide releases from commercial power reactors operating during 1987. Fifty-year dose commitments for a one-year exposure from both liquid and atmospheric releases were calculated for four population groups (infant, child, teen-ager and adult) residing between 2 and 80 km from each of 70 reactor sites. This report tabulates the results of these calculations, showing the dose commitments for both water and airborne pathways for each age group and organ. Also included for reach of the sites is a histogram showing the fraction of the total population within 2 to 80 km around each site receiving various average dose commitments from the airborne pathways. The site average individual dose commitment from all pathways ranged from a low of 2 x 10 -6 mrem to a high of 0.009 mrem. No attempt was made in this study to determine the maximum dose commitment received by any one individual from the radionuclides released at any of the sites. However, licensee calculation of doses to the maximally exposed individual at some sites indicated values of up to approximately 100 times average individual doses (on the order of a few millirem per year). 2 refs., 2 figs., 7 tabs

  5. Current regimen of pulse therapy for pemphigus: Minor modifications, improved results

    Directory of Open Access Journals (Sweden)

    Pasricha J

    2008-01-01

    Full Text Available Background: If administered properly, dexamethasone cyclophosphamide pulse (DCP therapy has the potential to effect lifelong recovery from pemphigus. Aims: The objective of this paper is to highlight various parameters of DCP therapy and also, to report the effects of a few modifications in the regimen. Methods: An analysis of 123 patients treated with the DCP/DP regimen over a period of five years (1998 to 2002 is presented here. Seventeen patients who did not start/continue the treatment and three patients who died during the treatment have been excluded from the analysis. Twenty patients who had not yet started families were given only dexamethasone pulses (DPs while 103 patients received DCPs. Low dose (50 mg/day cyclophosphamide was used as in the standard regimen. The three modifications introduced into the regimen were: (1 an additional daily dose of oral betamethasone sufficient to control the disease activity during phase I, which was progressively tapered off completely as the patient recovered, (2 use of systemic antibiotics if the patient had skin lesions, and oral anti-candida drugs if the patient had oral ulcers until complete healing, and (3 insistence on thorough cleaning of the skin and scalp with a normal soap and shampoo, and proper maintenance of oral hygiene in spite of skin/mucosal lesions. The regimen consisted of DCP/DP repeated in exactly 28-day cycles, along with 50 mg cyclophosphamide per day, insistence on completing the treatment and avoiding irregular pulses in all patients. The number of DCPs/DPs during phase I varied in different patients depending upon the dose of betamethasone used and the rate of recovery, but phase II (nine DCPs/DPs in exactly 28-day cycles along with 50 mg cyclophosphamide per day and phase III (only 50 mg cyclophosphamide per day was fixed at nine months each. This was followed by posttreatment follow-up (phase IV. Results: At present, all the patients are in complete remission. The

  6. Skin dose assessment in routine personnel beta/gamma dosimetry

    International Nuclear Information System (INIS)

    Christensen, P.

    1980-01-01

    Three alternative methods are outlined by which substantial improvements of the capabilities of existing routine monitoring systems for skin dose assessment can be obtained. The introduction of a supplementary skin dosemeter may be an attractive method for systems with badges that have a capability for an additional dosemeter already built-in. The two-side reading method has limited possibilities because of reduced accuracy for mixed radiation and technical difficulties in using it for TLD systems with planchet heating. The use of a boron diffused LiF layer for skin dose assessment seems to be most attractive method since the only modification needed here is replacement of a dosemeter. However the study of this method is so far only in a preliminary stage and further investigations are needed. (U.K.)

  7. Permit application modifications

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-11-01

    This document contains the Permit Application Modifications for the Y-12 Industrial Landfill V site on the Oak Ridge Reservation. These modifications include the assessment of stability of the proposed Landfill V under static and loading conditions. Analyses performed include the general slope stability, veneer stability of the bottom liner and cover system, and a liquefaction potential assessment of the foundation soils.

  8. Permit application modifications

    International Nuclear Information System (INIS)

    1995-11-01

    This document contains the Permit Application Modifications for the Y-12 Industrial Landfill V site on the Oak Ridge Reservation. These modifications include the assessment of stability of the proposed Landfill V under static and loading conditions. Analyses performed include the general slope stability, veneer stability of the bottom liner and cover system, and a liquefaction potential assessment of the foundation soils

  9. Maximal hypersurfaces and foliations of constant mean curvature in general relativity

    International Nuclear Information System (INIS)

    Marsden, J.E.; Tipler, F.J.; Texas Univ., Austin

    1980-01-01

    We prove theorems on existence, uniqueness and smoothness of maximal and constant mean curvature compact spacelike hypersurfaces in globally hyperbolic spacetimes. The uniqueness theorem for maximal hypersurfaces of Brill and Flaherty, which assumed matter everywhere, is extended to specetimes that are vacuum and non-flat or that satisfy a generic-type condition. In this connection we show that under general hypotheses, a spatially closed universe with a maximal hypersurface must be Wheeler universe; i.e. be closed in time as well. The existence of Lipschitz achronal maximal volume hypersurfaces under the hypothesis that candidate hypersurfaces are bounded away from the singularity is proved. This hypothesis is shown to be valid in two cases of interest: when the singularities are of strong curvature type, and when the singularity is a single ideal point. Some properties of these maximal volume hypersurfaces and difficulties with Avez' original arguments are discussed. The difficulties involve the possibility that the maximal volume hypersurface can be null on certain portions; we present an incomplete argument which suggests that these hypersurfaces are always smooth, but prove that an a priori bound on the second fundamental form does imply smoothness. An extension of the perturbation theorem of Choquet-Bruhat, Fischer and Marsden is given and conditions under which local foliantions by constant mean curvature hypersurfaces can be extended to global ones is obtained. (orig.)

  10. Maximal near-field radiative heat transfer between two plates

    OpenAIRE

    Nefzaoui, Elyes; Ezzahri, Younès; Drevillon, Jérémie; Joulain, Karl

    2013-01-01

    International audience; Near-field radiative transfer is a promising way to significantly and simultaneously enhance both thermo-photovoltaic (TPV) devices power densities and efficiencies. A parametric study of Drude and Lorentz models performances in maximizing near-field radiative heat transfer between two semi-infinite planes separated by nanometric distances at room temperature is presented in this paper. Optimal parameters of these models that provide optical properties maximizing the r...

  11. Optimal quantum error correcting codes from absolutely maximally entangled states

    Science.gov (United States)

    Raissi, Zahra; Gogolin, Christian; Riera, Arnau; Acín, Antonio

    2018-02-01

    Absolutely maximally entangled (AME) states are pure multi-partite generalizations of the bipartite maximally entangled states with the property that all reduced states of at most half the system size are in the maximally mixed state. AME states are of interest for multipartite teleportation and quantum secret sharing and have recently found new applications in the context of high-energy physics in toy models realizing the AdS/CFT-correspondence. We work out in detail the connection between AME states of minimal support and classical maximum distance separable (MDS) error correcting codes and, in particular, provide explicit closed form expressions for AME states of n parties with local dimension \

  12. Chemical modification and pH dependence of kinetic parameters to identify functional groups in a glucosyltransferase from Strep. Mutans

    International Nuclear Information System (INIS)

    Bell, J.E.; Leone, A.; Bell, E.T.

    1986-01-01

    A glucosyltransferase, forming a predominantly al-6 linked glucan, was partially purified from the culture filtrate of S. mutans GS-5. The kinetic properties of the enzyme, assessed using the transfer of 14 C glucose from sucrose into total glucan, were studied at pH values from pH 3.5 to 6.5. From the dependence of km on pH, a group with pKa = 5.5 must be protonated to maximize substrate binding. From plots of V/sub max/ vs pH two groups, with pKa's of 4.5 and 5.5 were indicated. The results suggest the involvement of either two carboxyl groups (one protonated, one unprotonated in the native enzyme) or a carboxyl group (unprotonated) and some other protonated group such as histidine, cysteine. Chemical modification studies showed that Diethylyrocarbonate (histidine specific) had no effect on enzyme activity while modification with p-phydroxy-mercuribenzoate or iodoacetic acid (sulfhydryl reactive) and carbodimide reagents (carboxyl specific) resulted in almost complete inactivation. Activity loss was dependent upon time of incubation and reagent concentration. The disaccharide lylose, (shown to be an inhibitor of the enzyme with similar affinity to sucrose) offers no protection against modification by the sulfhydryl reactive reagents

  13. Uncountably many maximizing measures for a dense subset of continuous functions

    Science.gov (United States)

    Shinoda, Mao

    2018-05-01

    Ergodic optimization aims to single out dynamically invariant Borel probability measures which maximize the integral of a given ‘performance’ function. For a continuous self-map of a compact metric space and a dense set of continuous functions, we show the existence of uncountably many ergodic maximizing measures. We also show that, for a topologically mixing subshift of finite type and a dense set of continuous functions there exist uncountably many ergodic maximizing measures with full support and positive entropy.

  14. Maximal Abelian sets of roots

    CERN Document Server

    Lawther, R

    2018-01-01

    In this work the author lets \\Phi be an irreducible root system, with Coxeter group W. He considers subsets of \\Phi which are abelian, meaning that no two roots in the set have sum in \\Phi \\cup \\{ 0 \\}. He classifies all maximal abelian sets (i.e., abelian sets properly contained in no other) up to the action of W: for each W-orbit of maximal abelian sets we provide an explicit representative X, identify the (setwise) stabilizer W_X of X in W, and decompose X into W_X-orbits. Abelian sets of roots are closely related to abelian unipotent subgroups of simple algebraic groups, and thus to abelian p-subgroups of finite groups of Lie type over fields of characteristic p. Parts of the work presented here have been used to confirm the p-rank of E_8(p^n), and (somewhat unexpectedly) to obtain for the first time the 2-ranks of the Monster and Baby Monster sporadic groups, together with the double cover of the latter. Root systems of classical type are dealt with quickly here; the vast majority of the present work con...

  15. Maximizing Function through Intelligent Robot Actuator Control

    Data.gov (United States)

    National Aeronautics and Space Administration — Maximizing Function through Intelligent Robot Actuator Control Successful missions to Mars and beyond will only be possible with the support of high-performance...

  16. The shape of the cancer mortality dose-response curve for atomic bomb survivors

    International Nuclear Information System (INIS)

    Pierce, D.A.; Vaeth, M.

    1989-10-01

    The shape of the cancer mortality dose-response in the atomic bomb survivor data is analyzed in the context of linear-quadratic (LQ) models. Results are given for all cancers except leukemia as a group, for leukemia, and for combined inferences assuming common curvature. Since there is substantial information aside from these data suggesting a dose-response concave from above, the emphasis here is not on estimating the best-fitting dose-response curve, but rather on assessing the maximal extent of curvature under LQ models which is consistent with the data. Such inferences are substantially affected by imprecision in the dose estimates, and methods are applied which make explicit allowances for biases due to this. The primary means used here to express the extent of curvature is the factor by which linear risk estimates should be divided to arrive at appropriate low-dose risk estimates. In the past, influential committees have recommended ranges of 2-10 and of 1.5-3 for such a factor. Results here suggest that values greater than about 2 are at least moderately inconsistent with these data, within the context of LQ models. It is emphasized, however, that there is little direct information in these data regarding low-dose risks; the inferences here depend strongly on the link between low-dose and high-dose risks provided by the assumption of an LQ model. (author)

  17. Behavior Modification in Coaching.

    Science.gov (United States)

    Lynch, Annette Rutt; Stillman, Stephen M.

    1979-01-01

    An example of behavior modification used in athletic coaching is presented. The case study involves a member of a women's basketball team and details the use of behavior modification for both weight reduction and skill improvement. (JMF)

  18. Evaluation of the distribution of absorbed dose in child phantoms exposed to diagnostic medical x rays

    Energy Technology Data Exchange (ETDEWEB)

    Chen, W. L.; Poston, J. W.; Warner, G. G.

    1978-04-01

    The purpose of this study was to determine, by theoretical calculation and experimental measurement, the absorbed dose distributions in two heterogeneous phantoms representing one-year- and five-year-old children from typical radiographic examinations for those ages. Theoretical work included the modification of an existing internal dose code which uses Monte Carlo methods to determine doses within the Snyder-Fisher mathematical phantom. A Ge(Li) detector and a pinhole collimator were used to measure x-ray spectra which served as input to the modified Monte Carlo codes which were used to calculate organ doses in children. The calculated and measured tissue-air values were compared for a number of organs. For most organs, the results of the calculated absorbed doses agreed with the measured absorbed doses within twice the coefficient of variation of the calculated value. The absorbed dose to specific organs for several selected radiological examinations are given for one-year-old, five-year-old, and adult phantoms.

  19. Evaluation of the distribution of absorbed dose in child phantoms exposed to diagnostic medical x rays

    International Nuclear Information System (INIS)

    Chen, W.L.; Poston, J.W.; Warner, G.G.

    1978-04-01

    The purpose of this study was to determine, by theoretical calculation and experimental measurement, the absorbed dose distributions in two heterogeneous phantoms representing one-year- and five-year-old children from typical radiographic examinations for those ages. Theoretical work included the modification of an existing internal dose code which uses Monte Carlo methods to determine doses within the Snyder-Fisher mathematical phantom. A Ge(Li) detector and a pinhole collimator were used to measure x-ray spectra which served as input to the modified Monte Carlo codes which were used to calculate organ doses in children. The calculated and measured tissue-air values were compared for a number of organs. For most organs, the results of the calculated absorbed doses agreed with the measured absorbed doses within twice the coefficient of variation of the calculated value. The absorbed dose to specific organs for several selected radiological examinations are given for one-year-old, five-year-old, and adult phantoms

  20. Associations of maximal strength and muscular endurance test scores with cardiorespiratory fitness and body composition.

    Science.gov (United States)

    Vaara, Jani P; Kyröläinen, Heikki; Niemi, Jaakko; Ohrankämmen, Olli; Häkkinen, Arja; Kocay, Sheila; Häkkinen, Keijo

    2012-08-01

    The purpose of the present study was to assess the relationships between maximal strength and muscular endurance test scores additionally to previously widely studied measures of body composition and maximal aerobic capacity. 846 young men (25.5 ± 5.0 yrs) participated in the study. Maximal strength was measured using isometric bench press, leg extension and grip strength. Muscular endurance tests consisted of push-ups, sit-ups and repeated squats. An indirect graded cycle ergometer test was used to estimate maximal aerobic capacity (V(O2)max). Body composition was determined with bioelectrical impedance. Moreover, waist circumference (WC) and height were measured and body mass index (BMI) calculated. Maximal bench press was positively correlated with push-ups (r = 0.61, p strength (r = 0.34, p strength correlated positively (r = 0.36-0.44, p test scores were related to maximal aerobic capacity and body fat content, while fat free mass was associated with maximal strength test scores and thus is a major determinant for maximal strength. A contributive role of maximal strength to muscular endurance tests could be identified for the upper, but not the lower extremities. These findings suggest that push-up test is not only indicative of body fat content and maximal aerobic capacity but also maximal strength of upper body, whereas repeated squat test is mainly indicative of body fat content and maximal aerobic capacity, but not maximal strength of lower extremities.

  1. Cycle length maximization in PWRs using empirical core models

    International Nuclear Information System (INIS)

    Okafor, K.C.; Aldemir, T.

    1987-01-01

    The problem of maximizing cycle length in nuclear reactors through optimal fuel and poison management has been addressed by many investigators. An often-used neutronic modeling technique is to find correlations between the state and control variables to describe the response of the core to changes in the control variables. In this study, a set of linear correlations, generated by two-dimensional diffusion-depletion calculations, is used to find the enrichment distribution that maximizes cycle length for the initial core of a pressurized water reactor (PWR). These correlations (a) incorporate the effect of composition changes in all the control zones on a given fuel assembly and (b) are valid for a given range of control variables. The advantage of using such correlations is that the cycle length maximization problem can be reduced to a linear programming problem

  2. Catalytic para-xylene maximization. Part X: Toluene disproportionation on HF promoted H-ZSM-5 catalysts

    Directory of Open Access Journals (Sweden)

    Ahmed K. Aboul-Gheit

    2012-12-01

    Full Text Available H-ZSM-5 zeolite catalysts were doped with 2%, 3% and 4%HF to be used for investigating their activities and selectivities for xylenes production and for para-xylene maximization at temperatures of 300–500 °C via toluene disproportionation. This doping caused pore size modification of the H-ZSM-5 catalyst. The reaction was carried out in a fixed bed flow type reactor. The ratio of produced para-xylene relative to its thermodynamic composition reached as high as 3.29 at 300 °C on the 4%HF doped H-ZSM-5 catalyst although this catalyst possessed the lowest amount of the largest pores (3.0–5.7 nm and the smallest pores (0.4–1.7 nm. The overall activities of the catalysts were decreased with an increase in HF doping because of diffusion restriction. The kinetics of the reaction were simply treated and found to give Ea and ΔS∗ values compatible with the characterization data of the catalysts.

  3. Calculation of absorbed dose for skin contamination imparted by beta radiation through the VARSKIN modified code for 122 interesting isotopes for nuclear medicine, nuclear power plants and research

    International Nuclear Information System (INIS)

    Alvarez R, J.T.

    1991-01-01

    In this work the implementation of a modification of the VARSKIN code for calculation of absorbed dose for contamination in skin imparted by external radiation fields generated by Beta emitting is presented. The modification consists on the inclusion of 47 isotopes of interest even Nuclear Plants for the dose evaluation in skin generated by 'hot particles'. The approach for to add these isotopes is the correlation parameter F and the average energy of the Beta particle, with relationship to those 75 isotopes of the original code. The methodology of the dose calculation of the VARSKIN code is based on the interpolation, (and integration of the interest geometries: punctual or plane sources), of the distribution functions scaled doses in water for beta and electrons punctual sources, tabulated by Berger. Finally a brief discussion of the results for their interpretation and use with purposes of radiological protection (dose insurance in relation to the considered biological effects) is presented

  4. Strategy to maximize maintenance operation

    OpenAIRE

    Espinoza, Michael

    2005-01-01

    This project presents a strategic analysis to maximize maintenance operations in Alcan Kitimat Works in British Columbia. The project studies the role of maintenance in improving its overall maintenance performance. It provides strategic alternatives and specific recommendations addressing Kitimat Works key strategic issues and problems. A comprehensive industry and competitive analysis identifies the industry structure and its competitive forces. In the mature aluminium industry, the bargain...

  5. The outcome of adjusted accumulation dose of treatment of Graves' disease

    International Nuclear Information System (INIS)

    Gomi, Yukari; Inoue, Takeshi; Suzuki, Seiji; Hamada, Noboru; Yoshimura, Hiroshi; Ishikawa, Naofumi; Momotani, Naoko; Ito, Kunihiko.

    1997-01-01

    We evaluated the outcome of 131 I treatment of Graves' disease in two different protocols (old and new protocol) of adjusted accumulation dose from 1988 to 1995. Adjusted accumulation doses of patients with above 50 g thyroid weights were increased by 5-20 Gy/g tissue in new protocol compared to those in old one. In 166 patients treated with single and plural doses of 131 I treatment in 1990 (Group In), the therapeutic doses were calculated according to new protocol and in 130 patients in 1988 (Group Io), according to old one, modification of Quimby's formula. The patients treated with plural doses were classified as hyperthyroidism because the efficacies of the first treatments with 131 I were insufficient. At the 5-yr follow up, the incidence of hypothyroid in Group In was 9%, subclinical hypothyroid 17%, euthyroid 30%, subclinical hyperthyroid 7%, hyperthyroid 37%. In Group Io, 11% of the patients were hypothyroid, 6% subclinical hypothyroid, 29% euthyroid, 3% subclinical hyperthyroid, 51% hyperthyroid. The incidence of hyperthyroid in Group In was lower than that in Group Io (p 131 I in relation to the patients' thyroid weight shows some room for improvement. (author)

  6. Maximizing the Range of a Projectile.

    Science.gov (United States)

    Brown, Ronald A.

    1992-01-01

    Discusses solutions to the problem of maximizing the range of a projectile. Presents three references that solve the problem with and without the use of calculus. Offers a fourth solution suitable for introductory physics courses that relies more on trigonometry and the geometry of the problem. (MDH)

  7. Maximization of eigenvalues using topology optimization

    DEFF Research Database (Denmark)

    Pedersen, Niels Leergaard

    2000-01-01

    to localized modes in low density areas. The topology optimization problem is formulated using the SIMP method. Special attention is paid to a numerical method for removing localized eigenmodes in low density areas. The method is applied to numerical examples of maximizing the first eigenfrequency, One example...

  8. Modification of DNA radiolysis by DNA-binding proteins: Structural aspects

    International Nuclear Information System (INIS)

    Davidkova, M.; Stisova, V.; Goffinont, S.; Gillard, N.; Castaing, B.; Spotheim-Maurizot, M.

    2006-01-01

    Formation of specific complexes between proteins and their cognate DNA modulates the yields and the location of radiation damage on both partners of the complex. The radiolysis of DNA-protein complexes is studied for: (1) the Escherichia coli lactose operator-repressor complex, (2) the complex between DNA bearing an analogue of an abasic site and the repair protein Fpg of Lactococcus lactis. Experimental patterns of DNA damages are presented and compared to predicted damage distribution obtained using an improved version of the stochastic model RADACK. The same method is used for predicting the location of damages on the proteins. At doses lower than a threshold that depends on the system, proteins protect their specific binding site on DNA while at high doses, the studied complexes are disrupted mainly through protein damage. The loss of binding ability is the functional consequence of the amino-acids modification by OH . radicals. Many of the most probably damaged amino acids are essential for the DNA-protein interaction and within a complex are protected by DNA. (authors)

  9. Estimation of maximal oxygen uptake without exercise testing in Korean healthy adult workers.

    Science.gov (United States)

    Jang, Tae-Won; Park, Shin-Goo; Kim, Hyoung-Ryoul; Kim, Jung-Man; Hong, Young-Seoub; Kim, Byoung-Gwon

    2012-08-01

    Maximal oxygen uptake is generally accepted as the most valid and reliable index of cardiorespiratory fitness and functional aerobic capacity. The exercise test for measuring maximal oxygen uptake is unsuitable for screening tests in public heath examinations, because of the potential risks of exercise exertion and time demands. We designed this study to determine whether work-related physical activity is a potential predictor of maximal oxygen uptake, and to develop a maximal oxygen uptake equation using a non-exercise regression model for the cardiorespiratory fitness test in Korean adult workers. Study subjects were adult workers of small-sized companies in Korea. Subjects with history of disease such as hypertension, diabetes, asthma and angina were excluded. In total, 217 adult subjects (113 men of 21-55 years old and 104 women of 20-64 years old) were included. Self-report questionnaire survey was conducted on study subjects, and maximal oxygen uptake of each subject was measured with the exercise test. The statistical analysis was carried out to develop an equation for estimating maximal oxygen uptake. The predictors for estimating maximal oxygen uptake included age, gender, body mass index, smoking, leisure-time physical activity and the factors representing work-related physical activity. The work-related physical activity was identified to be a predictor of maximal oxygen uptake. Moreover, the equation showed high validity according to the statistical analysis. The equation for estimating maximal oxygen uptake developed in the present study could be used as a screening test for assessing cardiorespiratory fitness in Korean adult workers.

  10. Maximal frustration as an immunological principle.

    Science.gov (United States)

    de Abreu, F Vistulo; Mostardinha, P

    2009-03-06

    A fundamental problem in immunology is that of understanding how the immune system selects promptly which cells to kill without harming the body. This problem poses an apparent paradox. Strong reactivity against pathogens seems incompatible with perfect tolerance towards self. We propose a different view on cellular reactivity to overcome this paradox: effector functions should be seen as the outcome of cellular decisions which can be in conflict with other cells' decisions. We argue that if cellular systems are frustrated, then extensive cross-reactivity among the elements in the system can decrease the reactivity of the system as a whole and induce perfect tolerance. Using numerical and mathematical analyses, we discuss two simple models that perform optimal pathogenic detection with no autoimmunity if cells are maximally frustrated. This study strongly suggests that a principle of maximal frustration could be used to build artificial immune systems. It would be interesting to test this principle in the real adaptive immune system.

  11. Social group utility maximization

    CERN Document Server

    Gong, Xiaowen; Yang, Lei; Zhang, Junshan

    2014-01-01

    This SpringerBrief explains how to leverage mobile users' social relationships to improve the interactions of mobile devices in mobile networks. It develops a social group utility maximization (SGUM) framework that captures diverse social ties of mobile users and diverse physical coupling of mobile devices. Key topics include random access control, power control, spectrum access, and location privacy.This brief also investigates SGUM-based power control game and random access control game, for which it establishes the socially-aware Nash equilibrium (SNE). It then examines the critical SGUM-b

  12. Dose - Response Curves for Dicentrics and PCC Rings: Preparedness for Radiological Emergency in Thailand

    International Nuclear Information System (INIS)

    Rungsimaphorn, B.; Rerkamnuaychoke, B.; Sudprasert, W.

    2014-01-01

    Establishing in-vitro dose calibration curves is important for reconstruction of radiation dose in the exposed individuals. The aim of this pioneering work in Thailand was to generate dose-response curves using conventional biological dosimetry: dicentric chromosome assay (DCA) and premature chromosome condensation (PCC) assay. The peripheral blood lymphocytes were irradiated with 137 Cs at a dose rate of 0.652 Gy/min to doses of 0.1, 0.25, 0.5, 0.75, 1, 2, 3, 4 and 5 Gy for DCA technique, and 5, 10, 15, 20 and 25 Gy for PCC technique. The blood samples were cultured and processed following the standard procedure given by the IAEA with slight modifications. At least 500-1,000 metaphases or 100 dicentrics/ PCC rings were analyzed using an automated metaphase finder system. The yield of dicentrics with dose was fitted to a linear quadratic model using Chromosome Aberration Calculation Software (CABAS, version 2.0), whereas the dose-response curve of PCC rings was fitted to a linear relationship. These curves will be useful for in-vitro dose reconstruction and can support the preparedness for radiological emergency in the country.

  13. Effect of follow-up period on minimal-significant dose in the atomic-bomb survivor studies

    Energy Technology Data Exchange (ETDEWEB)

    Cologne, John; Grant, Eric J.; Cullings, Harry M.; Ozasa, Kotaro [Radiation Effects Research Foundation, Hiroshima (Japan); Preston, Dale L. [Hirosoft International, Eureka, CA (United States)

    2018-03-15

    It was recently suggested that earlier reports on solid-cancer mortality and incidence in the Life Span Study of atomic-bomb survivors contain still-useful information about low-dose risk that should not be ignored, because longer follow-up may lead to attenuated estimates of low-dose risk due to longer time since exposure. Here it is demonstrated, through the use of all follow-up data and risk models stratified on period of follow-up (as opposed to sub-setting the data by follow-up period), that the appearance of risk attenuation over time may be the result of less-precise risk estimation - in particular, imprecise estimation of effect-modification parameters - in the earlier periods. Longer follow-up, in addition to allowing more-precise estimation of risk due to larger numbers of radiation-related cases, provides more-precise adjustment for background mortality or incidence and more-accurate assessment of risk modification by age at exposure and attained age. It is concluded that the latest follow-up data are most appropriate for inferring low-dose risk. Furthermore, if researchers are interested in effects of time since exposure, the most-recent follow-up data should be considered rather than the results of earlier reports. (orig.)

  14. Dynamical generation of maximally entangled states in two identical cavities

    International Nuclear Information System (INIS)

    Alexanian, Moorad

    2011-01-01

    The generation of entanglement between two identical coupled cavities, each containing a single three-level atom, is studied when the cavities exchange two coherent photons and are in the N=2,4 manifolds, where N represents the maximum number of photons possible in either cavity. The atom-photon state of each cavity is described by a qutrit for N=2 and a five-dimensional qudit for N=4. However, the conservation of the total value of N for the interacting two-cavity system limits the total number of states to only 4 states for N=2 and 8 states for N=4, rather than the usual 9 for two qutrits and 25 for two five-dimensional qudits. In the N=2 manifold, two-qutrit states dynamically generate four maximally entangled Bell states from initially unentangled states. In the N=4 manifold, two-qudit states dynamically generate maximally entangled states involving three or four states. The generation of these maximally entangled states occurs rather rapidly for large hopping strengths. The cavities function as a storage of periodically generated maximally entangled states.

  15. Impact of intra-arterial administration of boron compounds on dose-volume histograms in boron neutron capture therapy for recurrent head-and-neck tumors

    International Nuclear Information System (INIS)

    Suzuki, Minoru; Sakurai, Yoshinori; Nagata, Kenji; Kinashi, Yuko; Masunaga, Shinichiro; Ono, Koji; Maruhashi, Akira; Kato, Ituro; Fuwa, Nobukazu; Hiratsuka, Junichi; Imahori, Yoshio

    2006-01-01

    Purpose: To analyze the dose-volume histogram (DVH) of head-and-neck tumors treated with boron neutron capture therapy (BNCT) and to determine the advantage of the intra-arterial (IA) route over the intravenous (IV) route as a drug delivery system for BNCT. Methods and Materials: Fifteen BNCTs for 12 patients with recurrent head-and-neck tumors were included in the present study. Eight irradiations were done after IV administration of boronophenylalanine and seven after IA administration. The maximal, mean, and minimal doses given to the gross tumor volume were assessed using a BNCT planning system. Results: The results are reported as median values with the interquartile range. In the IA group, the maximal, mean, and minimal dose given to the gross tumor volume was 68.7 Gy-Eq (range, 38.8-79.9), 45.0 Gy-Eq (range, 25.1-51.0), and 13.8 Gy-Eq (range, 4.8-25.3), respectively. In the IV group, the maximal, mean, and minimal dose given to the gross tumor volume was 24.2 Gy-Eq (range, 21.5-29.9), 16.4 Gy-Eq (range, 14.5-20.2), and 7.8 Gy-Eq (range, 6.8-9.5), respectively. Within 1-3 months after BNCT, the responses were assessed. Of the 6 patients in the IV group, 2 had a partial response, 3 no change, and 1 had progressive disease. Of 4 patients in the IA group, 1 achieved a complete response and 3 a partial response. Conclusion: Intra-arterial administration of boronophenylalanine is a promising drug delivery system for head-and-neck BNCT

  16. Gap processing for adaptive maximal poisson-disk sampling

    KAUST Repository

    Yan, Dongming; Wonka, Peter

    2013-01-01

    In this article, we study the generation of maximal Poisson-disk sets with varying radii. First, we present a geometric analysis of gaps in such disk sets. This analysis is the basis for maximal and adaptive sampling in Euclidean space and on manifolds. Second, we propose efficient algorithms and data structures to detect gaps and update gaps when disks are inserted, deleted, moved, or when their radii are changed.We build on the concepts of regular triangulations and the power diagram. Third, we show how our analysis contributes to the state-of-the-art in surface remeshing. © 2013 ACM.

  17. Gap processing for adaptive maximal poisson-disk sampling

    KAUST Repository

    Yan, Dongming

    2013-10-17

    In this article, we study the generation of maximal Poisson-disk sets with varying radii. First, we present a geometric analysis of gaps in such disk sets. This analysis is the basis for maximal and adaptive sampling in Euclidean space and on manifolds. Second, we propose efficient algorithms and data structures to detect gaps and update gaps when disks are inserted, deleted, moved, or when their radii are changed.We build on the concepts of regular triangulations and the power diagram. Third, we show how our analysis contributes to the state-of-the-art in surface remeshing. © 2013 ACM.

  18. Anatomy of maximal stop mixing in the MSSM

    International Nuclear Information System (INIS)

    Bruemmer, Felix; Kraml, Sabine; Kulkarni, Suchita

    2012-05-01

    A Standard Model-like Higgs near 125 GeV in the MSSM requires multi-TeV stop masses, or a near-maximal contribution to its mass from stop mixing. We investigate the maximal mixing scenario, and in particular its prospects for being realized it in potentially realistic GUT models. We work out constraints on the possible GUT-scale soft terms, which we compare with what can be obtained from some well-known mechanisms of SUSY breaking mediation. Finally, we analyze two promising scenarios in detail, namely gaugino mediation and gravity mediation with non-universal Higgs masses.

  19. Anatomy of maximal stop mixing in the MSSM

    Energy Technology Data Exchange (ETDEWEB)

    Bruemmer, Felix [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Kraml, Sabine; Kulkarni, Suchita [CNRS/IN2P3, INPG, Grenoble (France). Laboratoire de Physique Subatomique et de Cosmologie

    2012-05-15

    A Standard Model-like Higgs near 125 GeV in the MSSM requires multi-TeV stop masses, or a near-maximal contribution to its mass from stop mixing. We investigate the maximal mixing scenario, and in particular its prospects for being realized it in potentially realistic GUT models. We work out constraints on the possible GUT-scale soft terms, which we compare with what can be obtained from some well-known mechanisms of SUSY breaking mediation. Finally, we analyze two promising scenarios in detail, namely gaugino mediation and gravity mediation with non-universal Higgs masses.

  20. Treatment plan evaluation using dose-volume histogram (DVH) and spatial dose-volume histogram (zDVH)

    International Nuclear Information System (INIS)

    Cheng, C.-W.; Das, Indra J.

    1999-01-01

    Objective: The dose-volume histogram (DVH) has been accepted as a tool for treatment-plan evaluation. However, DVH lacks spatial information. A new concept, the z-dependent dose-volume histogram (zDVH), is presented as a supplement to the DVH in three-dimensional (3D) treatment planning to provide the spatial variation, as well as the size and magnitude of the different dose regions within a region of interest. Materials and Methods: Three-dimensional dose calculations were carried out with various plans for three disease sites: lung, breast, and prostate. DVHs were calculated for the entire volume. A zDVH is defined as a differential dose-volume histogram with respect to a computed tomographic (CT) slice position. In this study, zDVHs were calculated for each CT slice in the treatment field. DVHs and zDVHs were compared. Results: In the irradiation of lung, DVH calculation indicated that the treatment plan satisfied the dose-volume constraint placed on the lung and zDVH of the lung revealed that a sizable fraction of the lung centered about the central axis (CAX) received a significant dose, a situation that warranted a modification of the treatment plan due to the removal of one lung. In the irradiation of breast with tangential fields, the DVH showed that about 7% of the breast volume received at least 110% of the prescribed dose (PD) and about 11% of the breast received less than 98% PD. However, the zDVHs of the breast volume in each of seven planes showed the existence of high-dose regions of 34% and 15%, respectively, of the volume in the two caudal-most planes and cold spots of about 40% in the two cephalic planes. In the treatment planning of prostate, DVHs showed that about 15% of the bladder and 40% of the rectum received 102% PD, whereas about 30% of the bladder and 50% of the rectum received the full dose. Taking into account the hollow structure of both the bladder and the rectum, the dose-surface histograms (DSH) showed larger hot-spot volume, about

  1. Nonlinear Impairment Compensation Using Expectation Maximization for PDM 16-QAM Systems

    DEFF Research Database (Denmark)

    Zibar, Darko; Winther, Ole; Franceschi, Niccolo

    2012-01-01

    We show experimentally that by using non-linear signal processing based algorithm, expectation maximization, nonlinear system tolerance can be increased by 2 dB. Expectation maximization is also effective in combating I/Q modulator nonlinearities and laser linewidth....

  2. Continuous infusion vs. bolus dosing: implications for beta-lactam antibiotics.

    Science.gov (United States)

    Mohd Hafiz, Abdul-Aziz; Staatz, C E; Kirkpatrick, C M J; Lipman, J; Roberts, J A

    2012-01-01

    Beta-lactam antibiotics display time-dependant pharmacodynamics whereby constant antibiotic concentrations rather than high peak concentrations are most likely to result in effective treatment of infections caused by susceptible bacteria. Continuous administration has been suggested as an alternative strategy, to conventional intermittent dosing, to optimise beta-lactam pharmacokinetic/pharmacodynamic (PK/PD) properties. With the availability of emerging data, we elected to systematically investigate the published literature describing the comparative PK/PD and clinical outcomes of beta-lactam antibiotics administered by continuous or intermittent infusion. We found that the studies have been performed in various patient populations including critically ill, cancer and cystic fibrosis patients. Available in vitro PK/PD data conclusively support the administration of beta-lactams via continuous infusion for maximizing bacterial killing from consistent attainment of pharmacodynamic end-points. In addition, clinical outcome data supports equivalence, even with the use of a lower dose by continuous infusion. However, the present clinical data is limited with small sample sizes common with insufficient power to detect advantages in favour of either dosing strategy. With abundant positive pre-clinical data as well as document in vivo PK/PD advantages, large multi-centre trials are needed to describe whether continuous administration of beta-lactams is truly more effective than intermittent dosing.

  3. Radiosurgery for Para-IAC Meningiomas: The Effect of Radiation Dose to the Cochlea on Hearing Outcome

    International Nuclear Information System (INIS)

    Kim, Young-Hoon; Kim, Dong Gyu; Han, Jung Ho; Chung, Hyun-Tai; Kim, In Kyung; Song, Sang Woo; Park, Jeong-Hoon; Kim, Jin Wook; Kim, Yong Hwy; Park, Chul-Kee; Kim, Chae-Yong; Paek, Sun Ha; Jung, Hee-Won

    2012-01-01

    Purpose: This study was performed to assess the radiosurgical results of meningiomas extending into the internal acoustic canal (para-IAC meningiomas), with a particular focus on the effect of radiation dose to the cochlea on hearing outcome. Methods and Materials: A total of 50 patients who underwent radiosurgery for para-IAC meningiomas between 1998 and 2009, which were followed for 2 years, were enrolled. The mean age was 55.8 years (range, 15–75). The mean tumor volume was 6.1 cm 3 (range, 1.0–19.0), the mean tumor length in the IAC was 6.9 mm (range, 1.3–13.3), and the mean prescribed marginal dose was 13.1 Gy (range, 10–15) at an isodose line of 50%. The mean follow-up duration was 46 months (range, 24–122). Results: Eight (16.0%) patients had nonserviceable hearing at the time of surgery. At the last follow-up, the tumor control rate was 94%; unchanged in 17 patients, decreased in 30 patients, and increased in 3 patients. Among 42 patients with serviceable hearing at the time of radiosurgery, it was preserved in 41 (97.6%) patients at the last follow-up. The maximal and mean radiation doses to the cochleae of these 41 patients were 5.8 Gy ± 0.3 (range, 3.1–11.5) and 4.3 Gy ± 0.2 (range, 2.2–7.5), respectively. The maximal dose to the cochlea of the patient who lost hearing after radiosurgery was 4.7 Gy. Conclusions: The radiation dose to the cochlea may have the minimal toxic effect on the hearing outcome in patients who undergo radiosurgery for para-IAC meningiomas.

  4. A New Look at the Impact of Maximizing on Unhappiness: Two Competing Mediating Effects

    Directory of Open Access Journals (Sweden)

    Jiaxi Peng

    2018-02-01

    Full Text Available The current study aims to explore how the decision-making style of maximizing affects subjective well-being (SWB, which mainly focuses on the confirmation of the mediator role of regret and suppressing role of achievement motivation. A total of 402 Chinese undergraduate students participated in this study, in which they responded to the maximization, regret, and achievement motivation scales and SWB measures. Results suggested that maximizing significantly predicted SWB. Moreover, regret and achievement motivation (hope for success dimension could completely mediate and suppress this effect. That is, two competing indirect pathways exist between maximizing and SWB. One pathway is through regret. Maximizing typically leads one to regret, which could negatively predict SWB. Alternatively, maximizing could lead to high levels of hope for success, which were positively correlated with SWB. Findings offered a complex method of thinking about the relationship between maximizing and SWB.

  5. A cosmological problem for maximally symmetric supergravity

    International Nuclear Information System (INIS)

    German, G.; Ross, G.G.

    1986-01-01

    Under very general considerations it is shown that inflationary models of the universe based on maximally symmetric supergravity with flat potentials are unable to resolve the cosmological energy density (Polonyi) problem. (orig.)

  6. Supplementation with low doses of vitamin E protects LDL from lipid peroxidation in men and women

    NARCIS (Netherlands)

    Princen, H.M.G.; Duyvenvoorde, W. van; Buytenhek, R.; Laarse, A. van der; Poppel, G. van; Gevers Leuven, J.A.; Hinsbergh, V.W.M. van

    1995-01-01

    There is accumulating evidence that oxidative modification of LDL is an important step in the process of atherogenesis and that antioxidants may protect LDL from oxidation. We and others have previously shown that ingestion of pharmacological doses of the antioxidant D,L-α-tocopherol (vitamin E),

  7. Outer measures and weak type estimates of Hardy-Littlewood maximal operators

    Directory of Open Access Journals (Sweden)

    Terasawa Yutaka

    2006-01-01

    Full Text Available We will introduce the times modified centered and uncentered Hardy-Littlewood maximal operators on nonhomogeneous spaces for . We will prove that the times modified centered Hardy-Littlewood maximal operator is weak type bounded with constant when if the Radon measure of the space has "continuity" in some sense. In the proof, we will use the outer measure associated with the Radon measure. We will also prove other results of Hardy-Littlewood maximal operators on homogeneous spaces and on the real line by using outer measures.

  8. Maximizing Tumor Immunity With Fractionated Radiation

    International Nuclear Information System (INIS)

    Schaue, Dörthe; Ratikan, Josephine A.; Iwamoto, Keisuke S.; McBride, William H.

    2012-01-01

    Purpose: Technologic advances have led to increased clinical use of higher-sized fractions of radiation dose and higher total doses. How these modify the pathways involved in tumor cell death, normal tissue response, and signaling to the immune system has been inadequately explored. Here we ask how radiation dose and fraction size affect antitumor immunity, the suppression thereof, and how this might relate to tumor control. Methods and Materials: Mice bearing B16-OVA murine melanoma were treated with up to 15 Gy radiation given in various-size fractions, and tumor growth followed. The tumor-specific immune response in the spleen was assessed by interferon-γ enzyme-linked immunospot (ELISPOT) assay with ovalbumin (OVA) as the surrogate tumor antigen and the contribution of regulatory T cells (Tregs) determined by the proportion of CD4 + CD25 hi Foxp3 + T cells. Results: After single doses, tumor control increased with the size of radiation dose, as did the number of tumor-reactive T cells. This was offset at the highest dose by an increase in Treg representation. Fractionated treatment with medium-size radiation doses of 7.5 Gy/fraction gave the best tumor control and tumor immunity while maintaining low Treg numbers. Conclusions: Radiation can be an immune adjuvant, but the response varies with the size of dose per fraction. The ultimate challenge is to optimally integrate cancer immunotherapy into radiation therapy.

  9. Reserve design to maximize species persistence

    Science.gov (United States)

    Robert G. Haight; Laurel E. Travis

    2008-01-01

    We develop a reserve design strategy to maximize the probability of species persistence predicted by a stochastic, individual-based, metapopulation model. Because the population model does not fit exact optimization procedures, our strategy involves deriving promising solutions from theory, obtaining promising solutions from a simulation optimization heuristic, and...

  10. Postactivation potentiation biases maximal isometric strength assessment.

    Science.gov (United States)

    Lima, Leonardo Coelho Rabello; Oliveira, Felipe Bruno Dias; Oliveira, Thiago Pires; Assumpção, Claudio de Oliveira; Greco, Camila Coelho; Cardozo, Adalgiso Croscato; Denadai, Benedito Sérgio

    2014-01-01

    Postactivation potentiation (PAP) is known to enhance force production. Maximal isometric strength assessment protocols usually consist of two or more maximal voluntary isometric contractions (MVCs). The objective of this study was to determine if PAP would influence isometric strength assessment. Healthy male volunteers (n = 23) performed two five-second MVCs separated by a 180-seconds interval. Changes in isometric peak torque (IPT), time to achieve it (tPTI), contractile impulse (CI), root mean square of the electromyographic signal during PTI (RMS), and rate of torque development (RTD), in different intervals, were measured. Significant increases in IPT (240.6 ± 55.7 N·m versus 248.9 ± 55.1 N·m), RTD (746 ± 152 N·m·s(-1) versus 727 ± 158 N·m·s(-1)), and RMS (59.1 ± 12.2% RMSMAX  versus 54.8 ± 9.4% RMSMAX) were found on the second MVC. tPTI decreased significantly on the second MVC (2373 ± 1200 ms versus 2784 ± 1226 ms). We conclude that a first MVC leads to PAP that elicits significant enhancements in strength-related variables of a second MVC performed 180 seconds later. If disconsidered, this phenomenon might bias maximal isometric strength assessment, overestimating some of these variables.

  11. Modification of nylon-6 fibres by radiation-induced graft polymerisation of vinylbenzyl chloride

    International Nuclear Information System (INIS)

    Ting, T.M.; Nasef, Mohamed Mahmoud; Hashim, Kamaruddin

    2015-01-01

    Modification of nylon-6 fibres by radiation-induced graft copolymerisation (RIGP) of vinylbenzyl chloride (VBC) using the preirradiation method was investigated. A number of grafting parameters such as type of solvent, total dose, monomer concentrations, reaction temperature and reaction time were studied to obtain desired degree of grafting (DG). The DG was found to be a function of reaction parameters and achieved a maximum value of 130 wt% at 20 vol% VBC concentration in methanol, 300 kGy dose, 30 °C temperature and 3 h reaction time. Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and X-ray diffraction (XRD) were employed to evaluate the chemical, morphological and structural changes that occurred in the grafted fibres, respectively. Thermogravimetric analysis (TGA) was also applied to determine the thermal stability, whereas differential scanning calorimeter (DSC) and universal mechanical tester were used to analyse respective thermal and mechanical properties of the grafted fibres. The results of these analyses provide strong evidence for successful grafting of VBC onto nylon-6, and the variation in the properties of the grafted fibres depends on DG. - Highlights: • Modification of nylon-6 fibres by radiation induced grafting of VBC in methanol. • Establishment of relations between DG and reaction parameters. • Evidence of VBC grafting was provided by FTIR, SEM, XRD, DSC and TGA. • The properties of VBC-grafted nylon-6 fibres depend on DG. • Amendable VBC-grafted nylon-6 fibres retain favourable properties

  12. Draft Air Pathway Report: Phase 1 of the Hanford Environmental Dose Reconstruction Project

    Energy Technology Data Exchange (ETDEWEB)

    1990-07-20

    This report summarizes the air pathway portion of the first phase of the Hanford Environmental Dose Reconstruction (HEDR) Project, conducted by Battelle staff at the Pacific Northwest Laboratory under the direction of an independent Technical Steering Panel. The HEDR Project is estimating historical radiation doses that could have been received by populations near the Department of Energy's Hanford Site, in southeastern Washington State. Phase 1 of the air-pathway dose reconstruction sought to determine whether dose estimates could be calculated for populations in the 10 counties nearest the Hanford Site from atmospheric releases of iodine-131 from the site from 1944--1947. Phase 1 demonstrated the following: HEDR-calculated source-term estimates of iodine-131 releases to the atmosphere were within 20% of previously published estimates; calculated vegetation concentrations of iodine-131 agree well with previously published measurements; the highest of the Phase 1 preliminary dose estimates to the thyroid are consistent with independent, previously published estimates of doses to maximally exposed individuals; and relatively crude, previously published measurements of thyroid burdens for Hanford workers are in the range of average burdens that the HEDR model estimated for similar reference individuals'' for the period 1944--1947. 4 refs., 10 figs., 9 tabs.

  13. Salinity effect on the maximal growth temperature of some bacteria isolated from marine enviroments.

    Science.gov (United States)

    Stanley, S O; Morita, R Y

    1968-01-01

    Salinity of the growth medium was found to have a marked effect on the maximal growth temperature of four bacteria isolated from marine sources. Vibrio marinus MP-1 had a maximal growth temperature of 21.2 C at a salinity of 35% and a maximal growth temperature of 10.5 C at a salinity of 7%, the lowest salinity at which it would grow. This effect was shown to be due to the presence of various cations in the medium. The order of effectiveness of cations in restoring the normal maximal growth temperature, when added to dilute seawater, was Na(+) > Li(+) > Mg(++) > K(+) > Rb(+) > NH(4) (+). The anions tested, with the exception of SO(4)=, had no marked effect on the maximal growth temperature response. In a completely defined medium, the highest maximal growth temperature was 20.0 C at 0.40 m NaCl. A decrease in the maximal growth temperature was observed at both low and high concentrations of NaCl.

  14. Pantex Plant Cell 12-44-1 tritium release: Re-assessment of environmental doses for 1990 to 1992

    International Nuclear Information System (INIS)

    Snyder, S.F.; Hwang, S.T.

    1994-03-01

    A release of tritium gas occurred within Cell 12-44-1 at the Pantex Plant on May 17, 1989. The release was the result of a nuclear component containment failure. This document summarizes past assessments and characterization of the release. From 1990 to 1992, the average annual dose to the offsite maximally exposed individual (MEI), re-assessed using updated methods and data, ranged from 9E-6 to 2E-4 mrem/y. Doses at this level are well below the regulatory dose limit and support the discontinuation of the distinct calculation of the MEI doses from the cell's tritium releases in future Pantex Annual Site Environmental Reports. Additional information provides guidance for the evaluation of similar releases in the future. Improved Environmental Protection Department sampling plans and assessment goals will increase the value of the data collected during future incidents

  15. A THEORY OF MAXIMIZING SENSORY INFORMATION

    NARCIS (Netherlands)

    Hateren, J.H. van

    1992-01-01

    A theory is developed on the assumption that early sensory processing aims at maximizing the information rate in the channels connecting the sensory system to more central parts of the brain, where it is assumed that these channels are noisy and have a limited dynamic range. Given a stimulus power

  16. Ehrenfest's Lottery--Time and Entropy Maximization

    Science.gov (United States)

    Ashbaugh, Henry S.

    2010-01-01

    Successful teaching of the Second Law of Thermodynamics suffers from limited simple examples linking equilibrium to entropy maximization. I describe a thought experiment connecting entropy to a lottery that mixes marbles amongst a collection of urns. This mixing obeys diffusion-like dynamics. Equilibrium is achieved when the marble distribution is…

  17. A Model of College Tuition Maximization

    Science.gov (United States)

    Bosshardt, Donald I.; Lichtenstein, Larry; Zaporowski, Mark P.

    2009-01-01

    This paper develops a series of models for optimal tuition pricing for private colleges and universities. The university is assumed to be a profit maximizing, price discriminating monopolist. The enrollment decision of student's is stochastic in nature. The university offers an effective tuition rate, comprised of stipulated tuition less financial…

  18. Analysis of renal impairment in MM-003, a phase III study of pomalidomide + low - dose dexamethasone versus high - dose dexamethasone in refractory or relapsed and refractory multiple myeloma

    Science.gov (United States)

    Weisel, Katja C.; Dimopoulos, Meletios A.; Moreau, Philippe; Lacy, Martha Q.; Song, Kevin W.; Delforge, Michel; Karlin, Lionel; Goldschmidt, Hartmut; Banos, Anne; Oriol, Albert; Alegre, Adrian; Chen, Christine; Cavo, Michele; Garderet, Laurent; Ivanova, Valentina; Martinez-Lopez, Joaquin; Knop, Stefan; Yu, Xin; Hong, Kevin; Sternas, Lars; Jacques, Christian; Zaki, Mohamed H.; Miguel, Jesus San

    2016-01-01

    Pomalidomide + low-dose dexamethasone is effective and well tolerated for refractory or relapsed and refractory multiple myeloma after bortezomib and lenalidomide failure. The phase III trial MM-003 compared pomalidomide + low-dose dexamethasone with high-dose dexamethasone. This subanalysis grouped patients by baseline creatinine clearance ≥ 30 − < 60 mL/min (n=93, pomalidomide + low-dose dexamethasone; n=56, high-dose dexamethasone) or ≥ 60 mL/min (n=205, pomalidomide + low-dose dexamethasone; n=93, high-dose dexamethasone). Median progression-free survival was similar for both subgroups and favored pomalidomide + low-dose dexamethasone versus high-dose dexamethasone: 4.0 versus 1.9 months in the group with baseline creatinine clearance ≥ 30 − < 60 mL/min (P<0.001) and 4.0 versus 2.0 months in the group with baseline creatinine clearance ≥ 60 mL/min (P<0.001). Median overall survival for pomalidomide + low-dose dexamethasone versus high-dose dexamethasone was 10.4 versus 4.9 months (P=0.030) and 15.5 versus 9.2 months (P=0.133), respectively. Improved renal function, defined as an increase in creatinine clearance from < 60 to ≥ 60 mL/min, was similar in pomalidomide + low-dose dexamethasone and high-dose dexamethasone patients (42% and 47%, respectively). Improvement in progression-free and overall survival in these patients was comparable with that in patients without renal impairment. There was no increase in discontinuations of therapy, dose modifications, and adverse events in patients with moderate renal impairment. Pomalidomide at a starting dose of 4 mg + low-dose dexamethasone is well tolerated in patients with refractory or relapsed and refractory multiple myeloma, and of comparable efficacy if moderate renal impairment is present. This trial was registered with clinicaltrials.gov identifier 01311687 and EudraCT identifier 2010-019820-30. PMID:27081177

  19. Maximizing Tumor Immunity With Fractionated Radiation

    Energy Technology Data Exchange (ETDEWEB)

    Schaue, Doerthe, E-mail: dschaue@mednet.ucla.edu [Department of Radiation Oncology, David Geffen School of Medicine at UCLA, Los Angeles, CA (United States); Ratikan, Josephine A.; Iwamoto, Keisuke S.; McBride, William H. [Department of Radiation Oncology, David Geffen School of Medicine at UCLA, Los Angeles, CA (United States)

    2012-07-15

    Purpose: Technologic advances have led to increased clinical use of higher-sized fractions of radiation dose and higher total doses. How these modify the pathways involved in tumor cell death, normal tissue response, and signaling to the immune system has been inadequately explored. Here we ask how radiation dose and fraction size affect antitumor immunity, the suppression thereof, and how this might relate to tumor control. Methods and Materials: Mice bearing B16-OVA murine melanoma were treated with up to 15 Gy radiation given in various-size fractions, and tumor growth followed. The tumor-specific immune response in the spleen was assessed by interferon-{gamma} enzyme-linked immunospot (ELISPOT) assay with ovalbumin (OVA) as the surrogate tumor antigen and the contribution of regulatory T cells (Tregs) determined by the proportion of CD4{sup +}CD25{sup hi}Foxp3{sup +} T cells. Results: After single doses, tumor control increased with the size of radiation dose, as did the number of tumor-reactive T cells. This was offset at the highest dose by an increase in Treg representation. Fractionated treatment with medium-size radiation doses of 7.5 Gy/fraction gave the best tumor control and tumor immunity while maintaining low Treg numbers. Conclusions: Radiation can be an immune adjuvant, but the response varies with the size of dose per fraction. The ultimate challenge is to optimally integrate cancer immunotherapy into radiation therapy.

  20. Dose estimation and radiation control measures for individuals having close contact with patients administered in vivo nuclear medicine

    International Nuclear Information System (INIS)

    Konishi, E.; Abe, K.; Kusama, T.

    1993-01-01

    Patients who have been administered radiopharmaceuticals become a source of exposure to a non-occupational individual helping in support and comfort of these patients. We measured external dose rates at several distances from 84 adult patients administered radiopharmaceuticals, and urinary excretion of radioactivity in their patients. And we estimated the maximal dose for persons having close contact with patients administered radiopharmaceuticals from the combination of these measurement data and scenarios of contact with patients. On the basis of the estimated values, we proposed the following dose constraint for care givers. (1) The dose constraint for a non-occupational care givers to an adult nuclear medicine patient should in no case exceed 300 μSv per patient per examination of any kind. (2) The dose constraint in ordinary examinations employing a radionuclide should not be greater than 15 μSv per patient per examination. (3 tabs.)