WorldWideScience

Sample records for cumulative thermal dose

  1. Determination of radionuclides and pathways contributing to cumulative dose

    Energy Technology Data Exchange (ETDEWEB)

    Napier, B.A.

    1992-12-01

    A series of scoping calculations has been undertaken to evaluate the absolute and relative contributions of different radionuclides and exposure pathways to doses that may have been received by individuals living in the vicinity of the Hanford Site. This scoping calculation (Calculation 004) examined the contributions of numerous radionuclides to cumulative dose via environmental exposures and accumulation in foods. Addressed in this calculation were the contributions to organ and effective dose of infants and adults from (1) air submersion and groundshine external dose, (2) inhalation, (3) ingestion of soil by humans, (4) ingestion of leafy vegetables, (5) ingestion of other vegetables and fruits, (6) ingestion of meat, (7) ingestion of eggs, and (8) ingestion of cows' milk from Feeding Regime 1, as described in calculation 002. This calculation specifically addresses cumulative radiation doses to infants and adults resulting from releases occurring over the period 1945 through 1972.

  2. Role of sulfite additives in wine induced asthma: single dose and cumulative dose studies

    OpenAIRE

    Vally, H; Thompson, P.

    2001-01-01

    BACKGROUND—Wine appears to be a significant trigger for asthma. Although sulfite additives have been implicated as a major cause of wine induced asthma, direct evidence is limited. Two studies were undertaken to assess sulfite reactivity in wine sensitive asthmatics. The first study assessed sensitivity to sulfites in wine using a single dose sulfited wine challenge protocol followed by a double blind, placebo controlled challenge. In the second study a cumulative dose su...

  3. Determination of radionuclides and pathways contributing to cumulative dose. Hanford Environmental Dose Reconstruction Project: Dose code recovery activities, Calculation 004

    Energy Technology Data Exchange (ETDEWEB)

    Napier, B.A.

    1992-12-01

    A series of scoping calculations has been undertaken to evaluate the absolute and relative contributions of different radionuclides and exposure pathways to doses that may have been received by individuals living in the vicinity of the Hanford Site. This scoping calculation (Calculation 004) examined the contributions of numerous radionuclides to cumulative dose via environmental exposures and accumulation in foods. Addressed in this calculation were the contributions to organ and effective dose of infants and adults from (1) air submersion and groundshine external dose, (2) inhalation, (3) ingestion of soil by humans, (4) ingestion of leafy vegetables, (5) ingestion of other vegetables and fruits, (6) ingestion of meat, (7) ingestion of eggs, and (8) ingestion of cows` milk from Feeding Regime 1, as described in calculation 002. This calculation specifically addresses cumulative radiation doses to infants and adults resulting from releases occurring over the period 1945 through 1972.

  4. Radiologic imaging in cystic fibrosis: cumulative effective dose and changing trends over 2 decades.

    LENUS (Irish Health Repository)

    O'Connell, Oisin J

    2012-06-01

    With the increasing life expectancy for patients with cystic fibrosis (CF), and a known predisposition to certain cancers, cumulative radiation exposure from radiologic imaging is of increasing significance. This study explores the estimated cumulative effective radiation dose over a 17-year period from radiologic procedures and changing trends of imaging modalities over this period.

  5. Mapping of the cumulative β-ray dose on the ground surface surrounding the Fukushima area

    Science.gov (United States)

    Endo, Satoru; Kajimoto, Tsuyoshi; Tanaka, Kenichi; Nguyen, Thanh T.; Hayashi, Gohei; Imanaka, Tetsuji

    2015-01-01

    A large amount of the fission products released by the Fukushima Daiichi Nuclear Power Plant (FDNPP) accident on 11 March 2011 was deposited in a wide area from Tohoku to northern Kanto. A map of the estimated cumulative β-ray dose (70 μm dose equivalent) on the soil surface for one year after the FDNPP accident has been prepared using previously reported calculation methods and the 2-km mesh survey data by MEXT. From this map of estimated dose, areas with a high cumulative β-ray dose on the soil surface for one year after the FDNPP accident were found to be located in the Akogi-Teshichiro to Akogi-Kunugidaira region in Namie Town, and in the southern Futaba Town to the northern Tomioka Town region. The highest estimated cumulative β-ray dose was 710 mSv for one year at Akogi-Teshichiro, Namie Town. PMID:26519736

  6. Cumulative high doses of inhaled formoterol have less systemic effects in asthmatic children 6-11 years-old than cumulative high doses of inhaled terbutaline

    DEFF Research Database (Denmark)

    Kaae, Rikke; Agertoft, Lone; Pedersen, Sören

    2004-01-01

    OBJECTIVES: To evaluate high dose tolerability and relative systemic dose potency between inhaled clinically equipotent dose increments of formoterol and terbutaline in children. METHODS: Twenty boys and girls (6-11 years-old) with asthma and normal ECGs were studied. Ten doses of formoterol (Oxis......) 4.5 microg (F4.5) or terbutaline (Bricanyl) 500 microg (T500) were inhaled cumulatively via a dry powder inhaler (Turbuhaler) over 1 h (three patients) or 2.5 h (17 patients) and compared to a day of no treatment, in a randomised, double-blind (active treatments only), crossover trial. Blood...... pressure (BP), ECG, plasma potassium, glucose, lactate, and adverse events were monitored up to 10 h to assess tolerability and relative systemic dose potency. RESULTS: Formoterol and terbutaline had significant beta2-adrenergic effects on most outcomes. Apart from the effect on systolic BP, QRS duration...

  7. Cumulative Doses of T-Cell Depleting Antibody and Cancer Risk after Kidney Transplantation.

    Directory of Open Access Journals (Sweden)

    Jenny H C Chen

    Full Text Available T-cell depleting antibody is associated with an increased risk of cancer after kidney transplantation, but a dose-dependent relationship has not been established. This study aimed to determine the association between cumulative doses of T-cell depleting antibody and the risk of cancer after kidney transplantation. Using data from the Australian and New Zealand Dialysis and Transplant Registry between 1997-2012, we assessed the risk of incident cancer and cumulative doses of T-cell depleting antibody using adjusted Cox regression models. Of the 503 kidney transplant recipients with 2835 person-years of follow-up, 276 (55%, 209 (41% and 18 (4% patients received T-cell depleting antibody for induction, rejection or induction and rejection respectively. The overall cancer incidence rate was 1,118 cancers per 100,000 patient-years, with 975, 1093 and 1377 cancers per 100,000 patient-years among those who had received 1-5 doses, 6-10 doses and >10 doses, respectively. There was no association between cumulative doses of T cell depleting antibody and risk of incident cancer (1-5: referent, 6-10: adjusted hazard ratio (HR 1.19, 95%CI 0.48-2.95, >10: HR 1.42, 95%CI 0.50-4.02, p = 0.801. This lack of association is contradictory to our hypothesis and is likely attributed to the low event rates resulting in insufficient power to detect significant differences.

  8. Relative Pesticide and Exposure Route Contribution to Aggregate and Cumulative Dose in Young Farmworker Children

    Directory of Open Access Journals (Sweden)

    Asa Bradman

    2012-01-01

    Full Text Available The Child-Specific Aggregate Cumulative Human Exposure and Dose (CACHED framework integrates micro-level activity time series with mechanistic exposure equations, environmental concentration distributions, and physiologically-based pharmacokinetic components to estimate exposure for multiple routes and chemicals. CACHED was utilized to quantify cumulative and aggregate exposure and dose estimates for a population of young farmworker children and to evaluate the model for chlorpyrifos and diazinon. Micro-activities of farmworker children collected concurrently with residential measurements of pesticides were used in the CACHED framework to simulate 115,000 exposure scenarios and quantify cumulative and aggregate exposure and dose estimates. Modeled metabolite urine concentrations were not statistically different than concentrations measured in the urine of children, indicating that CACHED can provide realistic biomarker estimates. Analysis of the relative contribution of exposure route and pesticide indicates that in general, chlorpyrifos non-dietary ingestion exposure accounts for the largest dose, confirming the importance of the micro-activity approach. The risk metrics computed from the 115,000 simulations, indicate that greater than 95% of these scenarios might pose a risk to children’s health from aggregate chlorpyrifos exposure. The variability observed in the route and pesticide contributions to urine biomarker levels demonstrate the importance of accounting for aggregate and cumulative exposure in establishing pesticide residue tolerances in food.

  9. Cumulative oxytocin dose during induction of labor according to maternal body mass index.

    Science.gov (United States)

    Roloff, Kristina; Peng, Sheppard; Sanchez-Ramos, Luis; Valenzuela, Guillermo J

    2015-10-01

    To determine the cumulative oxytocin dose needed to achieve vaginal delivery among obese and non-obese women. A retrospective study was undertaken of women with singleton, term (≥37 weeks) pregnancies who delivered at an institution in California, USA, between May 1 and July 31, 2012. Women were deemed to be obese when their body mass index (BMI; calculated as weight in kilograms divided by the square of height in meters) was 30 or above. Cumulative oxytocin doses were calculated for women who achieved vaginal delivery. Overall, 413 women were included. Among 357 women for whom BMI data were available, 204 (57.1%) were obese. Vaginal delivery was achieved in 379 women. Among women who received augmentation after spontaneous labor onset, obese women trended towards more cumulative oxytocin (minimum: 24.7 ± 100.5 mU among women with a BMI of 18.50-24.99; maximum: 1580.5 ± 2530.5 mU among women with a BMI of 35.00-39.99; P=0.086). Women who underwent induction of labor required significantly more oxytocin with increasing BMI class (Plabor. Obese women required a larger cumulative oxytocin dose to achieve vaginal birth during labor induction, but not during augmentation of labor. The physiology of spontaneous labor could supersede or influence the metabolic derangement facing obese patients undergoing induction of labor. Copyright © 2015 International Federation of Gynecology and Obstetrics. Published by Elsevier Ireland Ltd. All rights reserved.

  10. Evaluation of cumulative lead dose and longitudinal changes in structural MRI in former organolead workers

    Science.gov (United States)

    Schwartz, Brian S.; Caffo, Brian; Stewart, Walter F.; Hedlin, Haley; James, Bryan D.; Yousem, David; Davatzikos, Christos

    2010-01-01

    Objective We evaluated whether tibia lead was associated with longitudinal change in brain volumes and white matter lesions in male former lead workers and population-based controls in whom we have previously reported on the cognitive and structural consequences of cumulative lead dose. Methods We used linear regression to identify predictors of change in brain volumes and white matter lesion grade scores, using two MRIs an average of five years apart. Results On average, total brain volume declined almost 30 cm3, predominantly in gray matter. Increasing age at the first MRI was strongly associated with larger declines in volumes and greater increases in white matter lesion scores. Tibia lead was not associated with change in brain volumes or white matter lesion scores. Conclusions In former lead workers in whom cumulative lead dose was associated with progressive declines in cognitive function decades after occupational exposure had ended, cumulative lead dose was associated with earlier persistent effects on brain structure, but not with additional worsening over five years. PMID:20357679

  11. Estimation of the annual cumulative radiation dose received by the dentist in dental clinics in Chennai

    Directory of Open Access Journals (Sweden)

    Sanarpalayam Chinaswamy Selvamuthukumar

    2014-01-01

    Full Text Available Aim and Objectives: To estimate the annual cumulative radiation dose received by a dentist in a ′less than an ideally sized clinic′ in Chennai. The objective of the study is to estimate the annual cumulative radiation dose received by the dentist at various distances and various angulations from the x-ray tube. Study Design: The head of a mannequin model was mounted on the dental chair to simulate a patient′s head and three thermoluminescent dosimeter (TLD chips were kept at various distances and various angulations, at a constant height. The standard conventional intraoral dental radiographic unit was used, which was kept stationary, with a constant voltage of 70 Kv, 8 mA current, and a constant exposure time of 0.3 seconds. Ninety-two TLD chips were exposed 20 times a day with constant horizontal angulations for a period of one year. The reading from the TLD chips was obtained on a computer through a TLD Badge Reader. Statistical Analysis: Post Hoc tests and One-way analysis of variance (ANOVA were used. Results and Conclusion: A decreasing trend was obtained in the average radiation doses, as the distance increased from the x-ray source, and a highly significant difference in doses (P < 0.001% was found between 4 and 5.5 feet (ft. We found a minimum average radiation dose at an angle of 60° to 80° and behind the tube. The purpose of this study was to create awareness among dental professionals, who had ′less than an ideally sized clinic′. We recommend that the dentist follow guidelines suggested by the National Council on Radiation Protection and Measurements (NCRP, USA. From this study, it is clear that most clinics are of sizes that do not permit this distance (6 ft, and hence, it is recommended that they use suitable barriers.

  12. Age- and gender-specific estimates of cumulative CT dose over 5 years using real radiation dose tracking data in children

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Eunsol; Goo, Hyun Woo; Lee, Jae-Yeong [University of Ulsan College of Medicine, Asan Medical Center, Department of Radiology and Research Institute of Radiology, Seoul (Korea, Republic of)

    2015-08-15

    It is necessary to develop a mechanism to estimate and analyze cumulative radiation risks from multiple CT exams in various clinical scenarios in children. To identify major contributors to high cumulative CT dose estimates using actual dose-length product values collected for 5 years in children. Between August 2006 and July 2011 we reviewed 26,937 CT exams in 13,803 children. Among them, we included 931 children (median age 3.5 years, age range 0 days-15 years; M:F = 533:398) who had 5,339 CT exams. Each child underwent at least three CT scans and had accessible radiation dose reports. Dose-length product values were automatically extracted from DICOM files and we used recently updated conversion factors for age, gender, anatomical region and tube voltage to estimate CT radiation dose. We tracked the calculated CT dose estimates to obtain a 5-year cumulative value for each child. The study population was divided into three groups according to the cumulative CT dose estimates: high, ≥30 mSv; moderate, 10-30 mSv; and low, <10 mSv. We reviewed clinical data and CT protocols to identify major contributors to high and moderate cumulative CT dose estimates. Median cumulative CT dose estimate was 5.4 mSv (range 0.5-71.1 mSv), and median number of CT scans was 4 (range 3-36). High cumulative CT dose estimates were most common in children with malignant tumors (57.9%, 11/19). High frequency of CT scans was attributed to high cumulative CT dose estimates in children with ventriculoperitoneal shunt (35 in 1 child) and malignant tumors (range 18-49). Moreover, high-dose CT protocols, such as multiphase abdomen CT (median 4.7 mSv) contributed to high cumulative CT dose estimates even in children with a low number of CT scans. Disease group, number of CT scans, and high-dose CT protocols are major contributors to higher cumulative CT dose estimates in children. (orig.)

  13. Analysis of Cumulative Dose to Implanted Pacemaker According to Various IMRT Delivery Methods: Optimal Dose Delivery Versus Dose Reduction Strategy

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jeong Woo; Hong, Se Mie [Dept. of Radiation Oncology, Konkuk University Medical Center, Seoul (Korea, Republic of)

    2011-11-15

    Cancer patients with implanted cardiac pacemaker occasionally require radiotherapy. Pacemaker may be damaged or malfunction during radiotherapy due to ionizing radiation or electromagnetic interference. Although radiotherapy should be planned to keep the dose to pacemaker as low as possible not to malfunction ideally, current radiation treatment planning (RTP) system does not accurately calculate deposited dose to adjacent field border or area beyond irradiated fields. In terms of beam delivery techniques using multiple intensity modulated fields, dosimetric effect of scattered radiation in high energy photon beams is required to be detailed analyzed based on measurement data. The aim of this study is to evaluate dose discrepancies of pacemaker in a RTP system as compared to measured doses. We also designed dose reduction strategy limited value of 2 Gy for radiation treatment patients with cardiac implanted pacemaker. Total accumulated dose of 145 cGy based on in-vivo dosimetry was satisfied with the recommendation criteria to prevent malfunction of pacemaker in SS technique. However, the 2 mm lead shielder enabled the scattered doses to reduce up to 60% and 40% in the patient and the phantom, respectively. The SS technique with the lead shielding could reduce the accumulated scattered doses less than 100 cGy. Calculated and measured doses were not greatly affected by the beam delivery techniques. In-vivo and measured doses on pacemaker position showed critical dose discrepancies reaching up to 4 times as compared to planned doses in RTP. The current SS technique could deliver lower scattered doses than recommendation criteria, but use of 2 mm lead shielder contributed to reduce scattered doses by 60%. The tertiary lead shielder can be useful to prevent malfunction or electrical damage of implanted pacemakers during radiotherapy. It is required to estimate more accurate scattered doses of the patient or medical device in RTP to design proper dose reduction strategy.

  14. Prediction of the cumulated dose for external beam irradiation of prostate cancer patients with 3D-CRT technique

    Directory of Open Access Journals (Sweden)

    Giżyńska Marta

    2016-03-01

    Full Text Available Nowadays in radiotherapy, much effort is taken to minimize the irradiated volume and consequently minimize doses to healthy tissues. In our work, we tested the hypothesis that the mean dose distribution calculated from a few first fractions can serve as prediction of the cumulated dose distribution, representing the whole treatment. We made our tests for 25 prostate cancer patients treated with three orthogonal fields technique. We did a comparison of dose distribution calculated as a sum of dose distribution from each fraction with a dose distribution calculated with isocenter shifted for a mean setup error from a few first fractions. The cumulative dose distribution and predicted dose distributions are similar in terms of gamma (3 mm 3% analysis, under condition that we know setup error from seven first fractions. We showed that the dose distribution calculated for the original plan with the isocenter shifted to the point, defined as the original isocenter corrected of the mean setup error estimated from the first seven fractions supports our hypothesis, i.e. can serve as a prediction for cumulative dose distribution.

  15. Benchmark Dose Analysis from Multiple Datasets: The Cumulative Risk Assessment for the N-Methyl Carbamate Pesticides

    Science.gov (United States)

    The US EPA’s N-Methyl Carbamate (NMC) Cumulative Risk assessment was based on the effect on acetylcholine esterase (AChE) activity of exposure to 10 NMC pesticides through dietary, drinking water, and residential exposures, assuming the effects of joint exposure to NMCs is dose-...

  16. Estimated cumulative radiation dose received by diagnostic imaging during staging and treatment of operable Ewing sarcoma 2005-2012

    Energy Technology Data Exchange (ETDEWEB)

    Johnsen, Boel [Haukeland University Hospital, Centre for Nuclear Medicine and PET, Department of Radiology, P.O. Box 1400, Bergen (Norway); Fasmer, Kristine Eldevik [Haukeland University Hospital, Department of Oncology, Medical Physics Section, Bergen (Norway); Boye, Kjetil [Norwegian Radium Hospital, Oslo University Hospital, Department of Oncology, Oslo (Norway); Rosendahl, Karen; Aukland, Stein Magnus [Haukeland University Hospital, Department of Radiology, Paediatric Section, Bergen (Norway); University of Bergen, Department of Clinical Medicine, Bergen (Norway); Trovik, Clement [University of Bergen, Department of Clinical Medicine, Bergen (Norway); Haukeland University Hospital, Department of Surgery, Orthopaedic Section, Bergen (Norway); Biermann, Martin [Haukeland University Hospital, Centre for Nuclear Medicine and PET, Department of Radiology, P.O. Box 1400, Bergen (Norway); University of Bergen, Department of Clinical Medicine, Bergen (Norway)

    2017-01-15

    Patients with Ewing sarcoma are subject to various diagnostic procedures that incur exposure to ionising radiation. To estimate the radiation doses received from all radiologic and nuclear imaging episodes during diagnosis and treatment, and to determine whether {sup 18}F-fluorodeoxyglucose positron emission tomography - computed tomography ({sup 18}F-FDG PET-CT) is a major contributor of radiation. Twenty Ewing sarcoma patients diagnosed in Norway in 2005-2012 met the inclusion criteria (age <30 years, operable disease, uncomplicated chemotherapy and surgery, no metastasis or residual disease within a year of diagnosis). Radiation doses from all imaging during the first year were calculated for each patient. The mean estimated cumulative radiation dose for all patients was 34 mSv (range: 6-70), radiography accounting for 3 mSv (range: 0.2-12), CT for 13 mSv (range: 2-28) and nuclear medicine for 18 mSv (range: 2-47). For the patients examined with PET-CT, the mean estimated cumulative effective dose was 38 mSv, of which PET-CT accounted for 14 mSv (37%). There was large variation in number and type of examinations performed and also in estimated cumulative radiation dose. The mean radiation dose for patients examined with PET-CT was 23% higher than for patients not examined with PET-CT. (orig.)

  17. A methodology to split the total cumulative Hp(10) dose into the Hp(10) i doses received during various procedures performed by interventional cardiologist.

    Science.gov (United States)

    Domienik, Joanna

    2017-03-01

    The methodology describing how to split the cumulative Hp(10) dose of interventional cardiologists into Hp(10) i doses received during procedures of various types based on procedure-specific ELDO coefficients and Hp(3) doses per procedure is presented. The appropriate equations for Hp(10) i (Hp(10) for procedure type i), depending on the number of various procedure types (i  =  1 … 4) performed by a particular physician, are derived. The methodology can be applied to whole-body doses measured on the lead apron and therefore can be used for optimisation of work practices in those catheterisation labs where routine dosimeter is worn above the apron.

  18. When depth is no refuge: cumulative thermal stress increases with depth in Bocas del Toro, Panama

    Science.gov (United States)

    Neal, B. P.; Condit, C.; Liu, G.; dos Santos, S.; Kahru, M.; Mitchell, B. G.; Kline, D. I.

    2014-03-01

    Coral reefs are increasingly affected by high-temperature stress events and associated bleaching. Monitoring and predicting these events have largely utilized sea surface temperature data, due to the convenience of using large-scale remotely sensed satellite measurements. However, coral bleaching has been observed to vary in severity throughout the water column, and variations in coral thermal stress across depths have not yet been well investigated. In this study, in situ water temperature data from 1999 to 2011 from three depths were used to calculate thermal stress on a coral reef in Bahia Almirante, Bocas del Toro, Panama, which was compared to satellite surface temperature data and thermal stress calculations for the same area and time period from the National Oceanic and Atmospheric Administration Coral Reef Watch Satellite Bleaching Alert system. The results show similar total cumulative annual thermal stress for both the surface and depth-stratified data, but with a striking difference in the distribution of that stress among the depth strata during different high-temperature events, with the greatest thermal stress unusually recorded at the deepest measured depth during the most severe bleaching event in 2005. Temperature records indicate that a strong density-driven temperature inversion may have formed in this location in that year, contributing to the persistence and intensity of bleaching disturbance at depth. These results indicate that depth may not provide a stress refuge from high water temperature events in some situations, and in this case, the water properties at depth appear to have contributed to greater coral bleaching at depth compared to near-surface locations. This case study demonstrates the importance of incorporating depth-stratified temperature monitoring and small-scale oceanographic and hydrologic data for understanding and predicting local reef responses to elevated water temperature events.

  19. A study of the relationship between peak skin dose and cumulative air kerma in interventional neuroradiology and cardiology

    Energy Technology Data Exchange (ETDEWEB)

    Neil, S; Padgham, C; Martin, C J [Health Physics, Gartnavel Royal Hospital, Glasgow G12 0XH (United Kingdom)

    2010-12-01

    A study of peak skin doses (PSDs) during neuroradiology and cardiology interventional procedures has been carried out using Gafchromic XR-RV2 film. Use of mosaics made from squares held in cling film has allowed doses to the head to be mapped successfully. The displayed cumulative air kerma (CAK) has been calibrated in terms of cumulative entrance surface dose (CESD) and results indicate that this can provide a reliable indicator of the PSD in neuroradiology. Results linking PSD to CESD for interventional cardiology were variable, but CAK is still considered to provide the best option for use as an indicator of potential radiation-induced effects. A CESD exceeding 3 Gy is considered a suitable action level for triggering follow-up of patients in neuroradiology and cardiology for possible skin effects. Application of dose action levels defined in this way would affect 8% of neurological embolisation procedures and 5% of cardiology ablation and multiple stent procedures at the hospitals where the investigations were carried out. A close relationship was observed between CESD and dose-area product (DAP) for particular types of procedure, and DAPs of 200-300 Gy cm{sup 2} could be used as trigger levels where CAK readings were not available. The DAP value would depend on the mean field size and would need to be determined for each application.

  20. Sci—Thur AM: YIS - 11: Estimation of Bladder-Wall Cumulative Dose in Multi-Fraction Image-Based Gynaecological Brachytherapy Using Deformable Point Set Registration

    Energy Technology Data Exchange (ETDEWEB)

    Zakariaee, R [Physics Department, University of British Columbia, Vancouver, BC (Canada); Brown, C J; Hamarneh, G [School of Computing Science, Simon Fraser University, Burnaby, BC (Canada); Parsons, C A; Spadinger, I [British Columbia Cancer Agency, Vancouver, BC (Canada)

    2014-08-15

    Dosimetric parameters based on dose-volume histograms (DVH) of contoured structures are routinely used to evaluate dose delivered to target structures and organs at risk. However, the DVH provides no information on the spatial distribution of the dose in situations of repeated fractions with changes in organ shape or size. The aim of this research was to develop methods to more accurately determine geometrically localized, cumulative dose to the bladder wall in intracavitary brachytherapy for cervical cancer. The CT scans and treatment plans of 20 cervical cancer patients were used. Each patient was treated with five high-dose-rate (HDR) brachytherapy fractions of 600cGy prescribed dose. The bladder inner and outer surfaces were delineated using MIM Maestro software (MIM Software Inc.) and were imported into MATLAB (MathWorks) as 3-dimensional point clouds constituting the “bladder wall”. A point-set registration toolbox for MATLAB, Coherent Point Drift (CPD), was used to non-rigidly transform the bladder-wall points from four of the fractions to the coordinate system of the remaining (reference) fraction, which was chosen to be the emptiest bladder for each patient. The doses were accumulated on the reference fraction and new cumulative dosimetric parameters were calculated. The LENT-SOMA toxicity scores of these patients were studied against the cumulative dose parameters. Based on this study, there was no significant correlation between the toxicity scores and the determined cumulative dose parameters.

  1. Clinical significance of cumulative biological effective dose and overall treatment time in the treatment of carcinoma cervix

    Directory of Open Access Journals (Sweden)

    Mandal Abhijit

    2007-01-01

    Full Text Available The purpose of this retrospective study is to report the radiotherapy treatment response of, and complications in, patients with cervical cancer on the basis of cumulative biologic effective dose (BED and overall treatment time (OTT. Sixty-four (stage II - 35/64; stage III - 29/64 patients of cervical cancer were treated with combination of external beam radiotherapy (EBRT and low dose rate intracavitary brachytherapy (ICBT. The cumulative BED was calculated at Point A (BED 10 ; and bladder, rectal reference points (BED 2.5 using the linear-quadratic BED equations. The local control (LC rate and 5-year disease-free survival (DFS rate in patients of stage II were comparable for BED 10 < 84.5 and BED 10 > 84.5 but were much higher for BED 10 > 84.5 than BED 10 < 84.5 ( P < 0.01 in stage III patients. In the stage II patients, The LC rate and 5-year DFS rate were comparable for OTT < 50 days and for OTT> 50 days but were much higher in stage III patients with OTT < 50 than OTT> 50 days ( P < 0.001. It was also observed that patients who received BED 2.5 < 105 had lesser rectal ( P < 0.001 and bladder complications than BED 2.5 > 105. Higher rectal complication-free survival (CFS R rate, bladder complication-free survival (CFS B rate and all-type late complication-free survival rate were observed in patients who received BED 2.5 < 105 than BED 2.5 > 105. A balanced, optimal and justified radiotherapy treatment schedule to deliver higher BED 10 (>84.5 and lower BED 2.5 (< 105 in lesser OTT (< 50 days is essential in carcinoma cervix to expect a better treatment outcome in all respects.

  2. Unified registration framework for cumulative dose assessment in cervical cancer across external beam radiotherapy and brachytherapy

    Science.gov (United States)

    Roy, Sharmili; Totman, John J.; Choo, Bok A.

    2016-03-01

    Dose accumulation across External Beam Radiotherapy (EBRT) and Brachytherapy (BT) treatment fractions in cervical cancer is extremely challenging due to structural dissimilarities and large inter-fractional anatomic deformations between the EBRT and BT images. The brachytherapy applicator and the bladder balloon, present only in the BT images, introduce missing structural correspondences for the underlying registration problem. Complex anatomical deformations caused by the applicator and the balloon, different rectum and bladder filling and tumor shrinkage compound the registration difficulties. Conventional free-form registration methods struggle to handle such topological differences. In this paper, we propose a registration pipeline that first transforms the original images to their distance maps based on segmentations of critical organs and then performs non-linear registration of the distance maps. The resulting dense deformation field is then used to transform the original anatomical image. The registration accuracy is evaluated on 27 image pairs from stage 2B-4A cervical cancer patients. The algorithm reaches a Hausdorff distance of close to 0:5 mm for the uterus, 2:2 mm for the bladder and 1:7 mm for the rectum when applied to (EBRT,BT) pairs, taken at time points more than three months apart. This generalized model-free framework can be used to register any combination of EBRT and BT images as opposed to methods in the literature that are tuned for either only (BT,BT) pair, or only (EBRT,EBRT) pair or only (BT,EBRT) pair. A unified framework for 3D dose accumulation across multiple EBRT and BT fractions is proposed to facilitate adaptive personalized radiation therapy.

  3. Risk of therapy-related leukaemia and preleukaemia after Hodgkin's disease. Relation to age, cumulative dose of alkylating agents, and time from chemotherapy

    DEFF Research Database (Denmark)

    Pedersen-Bjergaard, J; Specht, L; Larsen, S O;

    1987-01-01

    391 patients treated intensively for Hodgkin's disease were followed for up to 15 years to evaluate the risk of therapy-related acute non-lymphocytic leukaemia (t-ANLL) and preleukaemia. Only two independent factors, patient age and cumulative dose of alkylating agents, were related to the risk o...

  4. Dose-Response Relationship between Cumulative Occupational Lead Exposure and the Associated Health Damages: A 20-Year Cohort Study of a Smelter in China.

    Science.gov (United States)

    Wu, Yue; Gu, Jun-Ming; Huang, Yun; Duan, Yan-Ying; Huang, Rui-Xue; Hu, Jian-An

    2016-03-16

    Long-term airborne lead exposure, even below official occupational limits, has been found to cause lead poisoning at higher frequencies than expected, which suggests that China's existing occupational exposure limits should be reexamined. A retrospective cohort study was conducted on 1832 smelting workers from 1988 to 2008 in China. These were individuals who entered the plant and came into continuous contact with lead at work for longer than 3 months. The dose-response relationship between occupational cumulative lead exposure and lead poisoning, abnormal blood lead, urinary lead and erythrocyte zinc protoporphyrin (ZPP) were analyzed and the benchmark dose lower bound confidence limits (BMDLs) were calculated. Statistically significant positive correlations were found between cumulative lead dust and lead fumes exposures and workplace seniority, blood lead, urinary lead and ZPP values. A dose-response relationship was observed between cumulative lead dust or lead fumes exposure and lead poisoning (p lead dust and fumes doses were 0.68 mg-year/m³ and 0.30 mg-year/m³ for lead poisoning, respectively. The BMDLs of workplace airborne lead concentrations associated with lead poisoning were 0.02 mg/m³ and 0.01 mg/m³ for occupational exposure lead dust and lead fume, respectively. In conclusion, BMDLs for airborne lead were lower than occupational exposure limits, suggesting that the occupational lead exposure limits need re-examination and adjustment. Occupational cumulative exposure limits (OCELs) should be established to better prevent occupational lead poisoning.

  5. DOSE-RESPONSE MODELING FOR THE ASSESSMENT OF CUMULATIVE RISK DUE TO EXPOSURE TO N-METHYL CARBAMATE PESTICIDES

    Science.gov (United States)

    The US EPAs N-Methyl Carbamate Cumulative Risk Assessment (NMCRA) assesses the effect on acetylcholine esterase (AChE) activity of exposure to 10 N-methyl carbamate (NMC) pesticides through dietary, drinking water, and residential exposures.

  6. The link between tissue elasticity and thermal dose in vivo

    Science.gov (United States)

    Sapin-de Brosses, Emilie; Pernot, Mathieu; Tanter, Mickaël

    2011-12-01

    The objective of this study was to investigate in vivo the relationship between stiffness and thermal dose. For this purpose, shear wave elastography (SWE)—a novel ultrasound-based technique for real-time mapping of the stiffness of biological soft tissues—is performed in temperature-controlled experiments. Experiments were conducted on nine anesthetized rats. Their right leg was put in a thermo-regulated waterbath. The right leg of each animal was heated at one particular temperature between 38 °C and 48.5 °C for 15 min to 3 h. Shear waves were generated in the muscle using the acoustic radiation force induced by a linear ultrasonic probe. The shear wave propagation was imaged in real time by the probe using an ultrafast scanner prototype (10 000 frames s-1). The local tissue stiffness was derived from the shear wave speed. Two optical fiber sensors were inserted into the muscle to measure in situ the temperature. Stiffness was found to increase strongly during the experiments. When expressed as a function of the thermal dose, the stiffness curves were found to be the same for all experiments. A thermal dose threshold was found at 202 min for an eightfold stiffness increase. Finally, the time-temperature relationship was established for different stiffness ratios. The slope of the time-temperature relationship based on stiffness measurements was found identical to the one obtained for cell death in the seminal paper on the thermal dose by Sapareto and Dewey in 1984 (Int. J. Radiat. Oncol. Biol. Phys. 10 787-800). The present results highlight the stiffness increase as a good indicator of thermal necrosis. SWE imaging can be used in vivo for necrosis threshold determination in thermal therapy.

  7. SU-E-J-106: The Use of Deformable Image Registration with Cone-Beam CT for a Better Evaluation of Cumulative Dose to Organs

    Energy Technology Data Exchange (ETDEWEB)

    Fillion, O; Gingras, L; Archambault, L [Universite Laval, Quebec, Quebec (Canada); Centre de recherche du CHU de Quebec, Quebec, Quebec (Canada); Centre de recherche sur le cancer, Quebec, Quebec (Canada)

    2015-06-15

    Purpose: The knowledge of dose accumulation in the patient tissues in radiotherapy helps in determining the treatment outcomes. This project aims at providing a workflow to map cumulative doses that takes into account interfraction organ motion without the need for manual re-contouring. Methods: Five prostate cancer patients were studied. Each patient had a planning CT (pCT) and 5 to 13 CBCT scans. On each series, a physician contoured the prostate, rectum, bladder, seminal vesicles and the intestine. First, a deformable image registration (DIR) of the pCTs onto the daily CBCTs yielded registered CTs (rCT) . This rCT combined the accurate CT numbers of the pCT with the daily anatomy of the CBCT. Second, the original plans (220 cGy per fraction for 25 fractions) were copied on the rCT for dose re-calculation. Third, the DIR software Elastix was used to find the inverse transform from the rCT to the pCT. This transformation was then applied to the rCT dose grid to map the dose voxels back to their pCT location. Finally, the sum of these deformed dose grids for each patient was applied on the pCT to calculate the actual dose delivered to organs. Results: The discrepancy between the planned D98 and D2 and these indices re-calculated on the rCT, are, on average, of −1 ± 1 cGy and 1 ± 2 cGy per fraction, respectively. For fractions with large anatomical motion, the D98 discrepancy on the re-calculated dose grid mapped onto the pCT can raise to −17 ± 4 cGy. The obtained cumulative dose distributions illustrate the same behavior. Conclusion: This approach allowed the evaluation of cumulative doses to organs with the help of uncontoured daily CBCT scans. With this workflow, the easy evaluation of doses delivered for EBRT treatments could ultimately lead to a better follow-up of prostate cancer patients.

  8. Current and historical individual data about exposure of workers in the rayon industry to carbon disulfide and their validity in calculating the cumulative dose.

    Science.gov (United States)

    Göen, Thomas; Schramm, Axel; Baumeister, Thomas; Uter, Wolfgang; Drexler, Hans

    2014-08-01

    The objective of the study was to investigate how exposure to carbon disulfide (CS2) in a rayon-manufacturing plant has changed within two decades and whether it is possible to calculate valid data for the individual cumulative exposure. The data for CS2 concentration in air and biological exposure monitoring (2-thio-1,3-thiaxolidine-4-carboxylic acid (TTCA) in urine) from two cross-sectional studies, performed in 1992 (n = 362) and 2009 (n = 212) in a German rayon-manufacturing plant, were compared to data obtained from company-internal measurements between the studies. Using the data from the cross-sectional studies and company-internal data, cumulative external exposure and the cumulative internal exposure were calculated for each worker. External and internal CS2 exposure of the employees decreased from 1992 (medians 4.0 ppm and 1.63 mgTTCA/g creatinine) to 2009 (medians 2.5 ppm and 0.86 mg/g). However, company-internal CS2 data do not show a straight trend for this period. The annual medians of the company-internal measurement of external exposure to CS2 have varied between 2.7 and 8.4 ppm, in which median values exceeded 5 ppm generally since 2000. The annual medians for the company-internal biomonitoring assessment ranged between 1.2 and 2.8 mg/g creatinine. The cumulative CS2 exposure ranged from 8.5 to 869.5 ppm years for external exposure and between 1.30 and 176.2 mg/g creatinine years for the internal exposure. Significant correlations were found between the current air pollution and the internal exposure in 2009 but also between the cumulative external and internal CS2 exposure. Current exposure data, usually collected in cross-sectional studies, rarely allow a reliable statement on the cumulative dose, because of higher exposure in the past and of fluctuating courses of exposure. On the other hand, company-internal exposure data may be affected by non-representative measurement strategies. Some verification of the reliability of

  9. Dose in a recreational water park with thermal water

    Energy Technology Data Exchange (ETDEWEB)

    Thomassin, A. [Institut de Radioprotection et de Surete Nucleaire (IRSN), 92 - Fontenay aux Roses (France)

    2006-07-01

    This paper assesses the annual effective dose received by the public due to baths in thermal water of a recreational water park in Royat (France) with significant levels of natural radionuclides. After the context be specified and the measurements of radioactivity presented, an assessment of radiological consequences is performed, based on an hypothetical scenario for persons of the public. Context The french commune of Royat in the Massif Central (centre of France) intends to build a recreational water park, using thermal water from a local source, out of the public water supply network. With this aim in view, the operator builds up a technical file to get a prefectorial authorization. Considering that many waters and thermal waters in this area have significant levels of natural radionuclides (granitic subsoil) on the one hand, and that the operator of establishments receiving public is requested by L 1333-10 article of the Public Health Code to supervise the exposure if an impact on health is possible on the other hand, the operator asked I.R.S.N. to measure the level of radioactivity in the water. Considering the level of radioactivity measured, the competent authority then asks I.R.S.N. if this level is compatible with its use in a recreational water park. After calculations it appears that in the particular case of the commune of Royat, the level of activity of natural radionuclides of the thermal water (22 Bq.L{sup -1} for {sup 222}Rn) is compatible with its use in a recreational water park, the annual effective dose being about 40 {mu}Sv with a conservative approach. For other thermal waters in France winch could have much higher levels of natural radioactivity, it is recommended to pay attention to their use in recreational water park. (N.C.)

  10. Double dose: the cumulative effect of TV viewing at home and in preschool on children's activity patterns and weight status.

    Science.gov (United States)

    Taverno Ross, Sharon; Dowda, Marsha; Saunders, Ruth; Pate, Russell

    2013-05-01

    Little is known about how screen-based sedentary behavior at home and in preschool influences children's health and activity patterns. The current study examined the individual and cumulative influence of TV viewing at home and in preschool on children's physical activity (PA) and weight status. Children (n = 339) attending 16 preschools in South Carolina were grouped into high and low TV groups based on parent report of children's TV viewing at home and director report of TV use/rules in preschool. T-tests and mixed model ANOVAs examined differences in weight status and PA (min/hr) by high and low TV groups. Results revealed that children who were classified as High TV both at home and in pre- school had significantly lower levels of moderate-to-vigorous PA compared with their Low TV counterparts (8.3 (0.3) min/hr vs. 7.6 (0.2) min/hr, p TV groups at home or in preschool when examined individually. These findings demonstrate the importance of total environmental TV exposure on preschooler's PA. Longitudinal and observational research to assess preschoolers' cumulative screen-based sedentary behavior and its relationship with PA and weight status is needed.

  11. A population-based case-control study of Selective Serotonin Reuptake Inhibitors (SSRIs and breast cancer: The impact of duration of use, cumulative dose and latency

    Directory of Open Access Journals (Sweden)

    Lévesque LE

    2010-12-01

    Full Text Available Abstract Background Selective serotonin reuptake inhibitors (SSRIs, a popular class of antidepressants, may increase breast cancer risk by stimulating the secretion of prolactin, a potential tumour promoter. We evaluated the effects of duration of SSRI use, cumulative dose, and latency on the risk of breast cancer by conducting a population-based case-control study utilizing Saskatchewan health databases. Methods Cases included 1,701 women with primary invasive breast cancer diagnosed from 2003 to 2006, and controls consisted of 17,017 women, randomly selected from the population registry. Use of SSRIs was compiled using the Saskatchewan prescription database. Unconditional logistic regression was conducted to evaluate the impact of duration of combined SSRI use (total number of prescriptions dispensed, cumulative dose (total dosage received and timing of use (two or more years, two to seven years and more than seven years prior to index date on the risk of breast cancer. Results Overall, SSRI use was not associated with an increased risk of breast cancer regardless of our definition of cumulative use (total number of prescriptions dispensed and total dosage. In addition, our results indicate that prolonged SSRI use does not have a latent effect on breast cancer risk. Also, our findings are not suggestive of an increased risk of breast cancer with the use of individual SSRIs. Conclusions Our study improved upon most previous studies by having a longer follow-up period, a larger sample size of long-term SSRI users and consideration of risk during specific exposure time windows that take latency into account. Given the potential health benefits of using SSRIs, our results suggest that the issue of breast cancer risk may no longer be a concern for women requiring long-term SSRIs.

  12. Measurement of radiocesium concentration in trees using cumulative gamma radiation dose rate detection systems - A simple presumption for radiocesium concentration in living woods using glass-badge based gamma radiation dose rate detection system

    Energy Technology Data Exchange (ETDEWEB)

    Yoshihara, T.; Hashida, S.N. [Plant Molecular Biology, Laboratory of Environmental Science, Central Research Institute of Electric Power Industry (CRIEPI), 1646 Abiko, Chiba 270-1194 (Japan); Kawachi, N.; Suzui, N.; Yin, Y.G.; Fujimaki, S. [Radiotracer Imaging Gr., Quantum Beam Science Center, Japan Atomic Energy Agency (JAEA), 1233 Watanuki, Takasaki, Gunma 370-1292 (Japan); Nagao, Y.; Yamaguchi, M. [Takasaki Advanced Radiation Research Institute, Japan Atomic Energy Agency (JAEA), 1233 Watanuki, Takasaki, Gunma 370-1292 (Japan)

    2014-07-01

    Radiocesium from the severe accident at the Fukushima Dai-ichi Nuclear Power Plant on 11 March 2011 contaminates large areas. After this, a doubt for forest products, especially of mushroom, is indelible at the areas. Pruned woody parts and litters are containing a considerable amount of radiocesium, and generates a problem at incineration and composting. These mean that more attentive survey for each subject is expected; however, the present survey system is highly laborious/expensive and/or non-effective for this purpose. On the other hand, we can see a glass-badge based gamma radiation dose rate detection system. This system always utilized to detect a personal cumulative radiation dose, and thus, it is not suitable to separate a radiation from a specific object. However, if we can separate a radiation from a specific object and relate it with the own radiocesium concentration, it would enable us to presume the specific concentration with just an easy monitoring but without a destruction of the target nature and a complicated process including sampling, pre-treatment, and detection. Here, we present the concept of the measurement and results of the trials. First, we set glass-badges (type FS, Chiyoda Technol Corp., Japan) on a part of bough (approximately 10 cm in diameter) of Japanese flowering cherry trees (Prunus x yedoensis cv. Somei-Yoshino) with four different settings: A, a direct setting without any shield; B, a setting with an aluminum shield between bough and the glass-badge; C, a setting with a lead shield between bough and the glass-badge; D, a setting with a lead shield covering the glass-badge to shut the radiation from the surrounding but from bough. The deduction between the amount of each setting should separate a specific radiation of the bough from unlimited radiation from the surrounding. Even if the hourly dose rate is not enough to count the difference, a moderate cumulative dose would clear the difference. In fact, results demonstrated a

  13. Integration of kerma-area product and cumulative air kerma determination into a skin dose tracking system for fluoroscopic imaging procedures

    Science.gov (United States)

    Vijayan, Sarath; Shankar, Alok; Rudin, Stephen; Bednarek, Daniel R.

    2016-03-01

    The skin dose tracking system (DTS) that we developed provides a color-coded mapping of the cumulative skin dose distribution on a 3D graphic of the patient during fluoroscopic procedures in real time. The DTS has now been modified to also calculate the kerma area product (KAP) and cumulative air kerma (CAK) for fluoroscopic interventions using data obtained in real-time from the digital bus on a Toshiba Infinix system. KAP is the integral of air kerma over the beam area and is typically measured with a large-area transmission ionization chamber incorporated into the collimator assembly. In this software, KAP is automatically determined for each x-ray pulse as the product of the air kerma/ mAs from a calibration file for the given kVp and beam filtration times the mAs per pulse times the length and width of the beam times a field nonuniformity correction factor. Field nonuniformity is primarily the result of the heel effect and the correction factor was determined from the beam profile measured using radio-chromic film. Dividing the KAP by the beam area at the interventional reference point provides the area averaged CAK. The KAP and CAK per x-ray pulse are summed after each pulse to obtain the total procedure values in real-time. The calculated KAP and CAK were compared to the values displayed by the fluoroscopy machine with excellent agreement. The DTS now is able to automatically calculate both KAP and CAK without the need for measurement by an add-on transmission ionization chamber.

  14. Investigation of practical approaches to evaluating cumulative dose for cone beam computed tomography (CBCT) from standard CT dosimetry measurements: a Monte Carlo study

    Science.gov (United States)

    Abuhaimed, Abdullah; Martin, Colin J.; Sankaralingam, Marimuthu; Gentle, David J.

    2015-07-01

    A function called Gx(L) was introduced by the International Commission on Radiation Units and Measurements (ICRU) Report-87 to facilitate measurement of cumulative dose for CT scans within long phantoms as recommended by the American Association of Physicists in Medicine (AAPM) TG-111. The Gx(L) function is equal to the ratio of the cumulative dose at the middle of a CT scan to the volume weighted CTDI (CTDIvol), and was investigated for conventional multi-slice CT scanners operating with a moving table. As the stationary table mode, which is the basis for cone beam CT (CBCT) scans, differs from that used for conventional CT scans, the aim of this study was to investigate the extension of the Gx(L) function to CBCT scans. An On-Board Imager (OBI) system integrated with a TrueBeam linac was simulated with Monte Carlo EGSnrc/BEAMnrc, and the absorbed dose was calculated within PMMA, polyethylene (PE), and water head and body phantoms using EGSnrc/DOSXYZnrc, where the body PE body phantom emulated the ICRU/AAPM phantom. Beams of width 40-500 mm and beam qualities at tube potentials of 80-140 kV were studied. Application of a modified function of beam width (W) termed Gx(W), for which the cumulative dose for CBCT scans f (0) is normalized to the weighted CTDI (CTDIw) for a reference beam of width 40 mm, was investigated as a possible option. However, differences were found in Gx(W) with tube potential, especially for body phantoms, and these were considered to be due to differences in geometry between wide beams used for CBCT scans and those for conventional CT. Therefore, a modified function Gx(W)100 has been proposed, taking the form of values of f (0) at each position in a long phantom, normalized with respect to dose indices f 100(150)x measured with a 100 mm pencil ionization chamber within standard 150 mm PMMA phantoms, using the same scanning parameters, beam widths and positions within the phantom. f 100(150)x averages the dose resulting from

  15. Leukaemia and low dose radiation. Is there an association between leukaemia and cumulative external dose amongst the British Nuclear Fuel plc. (BNFL) workers?

    Energy Technology Data Exchange (ETDEWEB)

    McGeoghegan, D.; Binks, K. [Westlakes Scientific Consulting, Cumbria (United Kingdom)

    2000-05-01

    A detailed examination of the BNFL leukaemia data is presented, for the period 1941-1995, using the recently assembled company wide BNFL epidemiological database and the BNFL leukaemia case-control data set. The association of this occupationally exposed cohort is examined with respect to both leukaemia mortality and leukaemia morbidity. The excess relative risk for total leukaemia excluding chronic lymphatic leukaemia amongst the BNFL radiation workers was found to be 3.64 Sv{sup -1} (90% CI -0.13-11.22); for Sellafield and Springfields this figure was 7.99 Sv{sup -1} (90% CI 1.50-29.5) and -1.97 Sv{sup -1} (90% CI<-2.23-6.11) respectively. A 14-20% increase in risk is noted when dosimetry adjusted for measurement error, is used to determine the excess relative risk. The association between leukaemia and cumulative external radiation is found to be particularly associated with the Sellafield plant; the Springfields plant gave consistently negative risk estimates. (author)

  16. The cumulative cost of additional wakefulness: dose-response effects on neurobehavioral functions and sleep physiology from chronic sleep restriction and total sleep deprivation

    Science.gov (United States)

    Van Dongen, Hans P A.; Maislin, Greg; Mullington, Janet M.; Dinges, David F.

    2003-01-01

    OBJECTIVES: To inform the debate over whether human sleep can be chronically reduced without consequences, we conducted a dose-response chronic sleep restriction experiment in which waking neurobehavioral and sleep physiological functions were monitored and compared to those for total sleep deprivation. DESIGN: The chronic sleep restriction experiment involved randomization to one of three sleep doses (4 h, 6 h, or 8 h time in bed per night), which were maintained for 14 consecutive days. The total sleep deprivation experiment involved 3 nights without sleep (0 h time in bed). Each study also involved 3 baseline (pre-deprivation) days and 3 recovery days. SETTING: Both experiments were conducted under standardized laboratory conditions with continuous behavioral, physiological and medical monitoring. PARTICIPANTS: A total of n = 48 healthy adults (ages 21-38) participated in the experiments. INTERVENTIONS: Noctumal sleep periods were restricted to 8 h, 6 h or 4 h per day for 14 days, or to 0 h for 3 days. All other sleep was prohibited. RESULTS: Chronic restriction of sleep periods to 4 h or 6 h per night over 14 consecutive days resulted in significant cumulative, dose-dependent deficits in cognitive performance on all tasks. Subjective sleepiness ratings showed an acute response to sleep restriction but only small further increases on subsequent days, and did not significantly differentiate the 6 h and 4 h conditions. Polysomnographic variables and delta power in the non-REM sleep EEG-a putative marker of sleep homeostasis--displayed an acute response to sleep restriction with negligible further changes across the 14 restricted nights. Comparison of chronic sleep restriction to total sleep deprivation showed that the latter resulted in disproportionately large waking neurobehavioral and sleep delta power responses relative to how much sleep was lost. A statistical model revealed that, regardless of the mode of sleep deprivation, lapses in behavioral alertness

  17. Promoter region variation in NFE2L2 influences susceptibility to ototoxicity in patients exposed to high cumulative doses of cisplatin.

    Science.gov (United States)

    Spracklen, T F; Vorster, A A; Ramma, L; Dalvie, S; Ramesar, R S

    2016-07-26

    Ototoxicity is a disabling reaction to cisplatin chemotherapy. Much of the inter-individual variability in the development of hearing impairment among cisplatin-receiving patients has not been fully accounted for. In particular, little is known about the pharmacogenomics of cisplatin-induced ototoxicity. This study sought to investigate the role of variation in five candidate genes in a cohort of South African cancer patients. Five variants within the candidate genes were genotyped in 214 patients, of which SLC22A2 rs316019 and NFE2L2 rs6721961 associated with reduced rates of ototoxicity. In the patients who were exposed to cumulative cisplatin doses ⩾200 mg m(-)(2) (n=113), the variant rs6721961 associated with ototoxicity according to three different grading scales of hearing loss (ASHA, P=0.005; Chang, P=0.028; CTCAE, P=0.004). The NFE2L2 promotor variant rs6721961 may therefore be protective against hearing loss in cisplatin-receiving cancer patients.The Pharmacogenomics Journal advance online publication, 26 July 2016; doi:10.1038/tpj.2016.52.

  18. The Effect of Total Cumulative Dose, Number of Treatment Cycles, Interval between Injections, and Length of Treatment on the Frequency of Occurrence of Antibodies to Botulinum Toxin Type A in the Treatment of Muscle Spasticity

    Science.gov (United States)

    Bakheit, Abdel Magid O.; Liptrot, Anthea; Newton, Rachel; Pickett, Andrew M.

    2012-01-01

    A large cumulative dose of botulinum toxin type A (BoNT-A), frequent injections, a short interval between treatment cycles, and a long duration of treatment have all been suggested, but not confirmed, to be associated with a high incidence of neutralizing antibodies to the neurotoxin. The aim of this study was to investigate whether these…

  19. Thermal-stress effects on enhanced low-dose-rate sensitivity of linear bipolar circuits

    Energy Technology Data Exchange (ETDEWEB)

    SHANEYFELT,MARTY R.; SCHWANK,JAMES R.; WITCZAK,STEVEN C.; RIEWE,LEONARD CHARLES; WINOKUR,PETER S.; HASH,GERALD L.; PEASE,R.L.; FLEETWOOD,D.M.

    2000-02-17

    Thermal-stress effects are shown to have a significant impact on the enhanced low-dose-rate sensitivity of linear bipolar circuits. Implications of these results on hardness assurance testing and mechanisms are discussed.

  20. Cumulative radiation dose of multiple trauma patients during their hospitalization%多发伤患者住院期间X射线累积有效剂量研究

    Institute of Scientific and Technical Information of China (English)

    王志康; 孙建忠; 赵祖丹

    2012-01-01

    Objective To study the cumulative radiation dose of multiple trauma patients during their hospitalization and to analyze the dose influece factors.Methods The DLP for CT and DR were retrospectively collected from the patients during June,2009 and April,2011 at a university affiliated hospital.The cumulative radiation doses were calculated by summing typical effective doses of the anatomic regions scanned.Results The cumulative radiation doses of 113 patients were collected.The maximum,minimum and the mean values of cumulative effective doses were 153.3,16.48 mSv and(52.3 ± 26.6) mSv.Conclusions Multiple trauma patients have high cumulative radiation exposure.Therefore,the management of cumulative radiation doses should be enhanced.To establish the individualized radiation exposure archives will be helpful for the clinicians and technicians to make decision wheather to image again and how to select the imaging parameters.%目的 研究多发伤患者在院治疗期间的累积医疗X射线检查剂量,探讨其影响因素.方法 回顾性收集2009年6月至2011年4月在本院治疗患者的CT、DR检查记录,CT记录其DLP值,并用各部位转换系数算出有效剂量;DR参照以往研究各部位有效剂量数据.结果 共收集113位患者的X射线检查的累积剂量,剂量范围16.48~153.3 mSv,平均(52.3±26.6)mSv.结论 多发伤患者其累积X射线剂量处于较高的水平.应加强对医疗X射线检查的累积剂量管理,通过建立患者X射线辐射剂量档案管理可能使临床医生、检查技术员重视检查开单的选择以及检查参数的合理设置.

  1. A combined cumulative threshold spectra and digital reconstruction analysis reveal structural alterations of microglia within the prefrontal cortex following low-dose LPS administration.

    Science.gov (United States)

    Kongsui, R; Johnson, S J; Graham, B A; Nilsson, M; Walker, F R

    2015-12-01

    Sickness behaviors have become the focus of great interest in recent years as they represent a clear case of how peripheral disturbances in immune signaling can disrupt quite complex behaviors. In the current study, we were interested in examining whether we could identify any significant morphological disturbances in microglia associated with these sickness-like behaviors in adult male Sprague-Dawley rats. We chose lipopolysaccharide (LPS 100 μg/kg/i.p.), to induce sickness-like behaviors as it is the most well-validated approach to do so in rodents and humans. We were particularly interested in examining changes in microglia within the prefrontal cortex (PFC) as several recent neuroimaging studies have highlighted significant functional changes in this region following peripheral LPS administration. Paraformaldehyde-fixed tissue was collected from animals 24h post LPS administration and labeled immunohistochemically with an antibody directed to bind to Iba-1, a protein known to be involved in the structural remodeling of microglia. To analyze changes, we have made use of two recently described image analysis procedures. The first is known as cumulative threshold spectra (CTS) analysis. The second involves the unsupervised digital reconstruction of microglia. We undertook these complementary analysis of microglial cells in the both the pre- and infralimbic divisions of the PFC. Our results indicated that microglial soma size was significantly enlarged, while cell processes had contracted slightly following LPS administration. To our knowledge this study is to first to definitely demonstrate substantial microglial disturbances within the PFC following LPS delivered at a dose that was sufficient to induce significant sickness-like behavior.

  2. Catarata em corticoterapia sistêmica: prevalência e relação com tempo e dose cumulativa de glicocorticóides Corticosteroid therapy and cataract: prevalence and relation to time of use and cumulative dose

    Directory of Open Access Journals (Sweden)

    Fernanda Ziger

    2003-01-01

    Full Text Available OBJETIVO: O presente estudo teve por finalidade estudar a freqüência de catarata em pacientes reumáticos e usuários crônicos de corticóide, procurando-se correlacionar o seu aparecimento com tempo de uso, dose cumulativa total e doença de fundo. MÉTODOS: Foram estudados 27 pacientes reumáticos usuários crônicos de corticóide, com exame de lâmpada de fenda e calculado o tempo de uso e doses cumulativas de prednisona ou equivalente. RESULTADO: Encontrou-se freqüência de 18,52% de cataratas e não foi possível demonstrar correlação com dose cumulativa do medicamento (p=0,231 ou com o tipo de doença de fundo. Apesar do tempo médio de uso de corticóide ter sido maior entre os pacientes que apresentaram catarata, esta correlação não demostrou significância estatística (p=0,694. CONCLUSÃO: Os autores concluem que esta complicação é relativamente comum e que mais estudos são necessários para melhor entender o processo fisiopatológico implicado na sua formação.PURPOSE: To study cataract prevalence in rheumatic patients who used corticosteroid chronically and to correlate it with time and total corticosteroid dose as well as with the disease that required such treatment. METHODS: We studied 27 rheumatic patients regarding cataract using slit lamp and calculated the total dose of prednisone or equivalent steroids as well as the treatment time. RESULTS: We found an 18.52% prevalence and no correlation with cumulative dose (p=0.231 or with the underlying disease. Although the time of treatment was longer in the group with cataract, no statistically significant difference could be found (p=0.694. CONCLUSION: The authors conclude that cataract is a relativelly common complication of steroid use and that further studies are needed to understand the pathophysiologic process of its formation.

  3. Gel dosimeters as useful dose and thermal-fluence detectors in Boron Neutron Capture Therapy (BNCT)

    Energy Technology Data Exchange (ETDEWEB)

    Gambarini, G.; Valente, M. [Department of Physics of the University and INFN, Via Celoria 16, I-20133 Milan (Italy); Moss, R.L.; Daquino, G.G.; Nievaart, V.A. [Joint Research Centre, Institute for Energy, P.O. Box 2, NL-1755ZG Petten, The Netherlands (Netherlands); Mariani, M.; Vanossi, E. [Department of Nuclear Engineering of Polytechnic, CESNEF, Via Ponzio, 34/3 - I-20133 Milan (Italy); Carrara, M. [Medical Physics Department, National Cancer Institute, Via Venezian 1, I-20131, Milan (Italy)

    2006-07-01

    The dosimetry method based on Fricke-Xylenol-Orange-infused gels in form of layers has shown noticeable potentiality for in-phantom or in-free-beam dose and thermal flux profiling and imaging in the high fluxes of thermal or epithermal neutrons utilised for boron neutron capture therapy (BNCT). Gel-dosimeters in form of layers give the possibility not only of obtaining spatial dose distributions but also of achieving measurements of each dose contribution in neutron fields. The discrimination of the various dose components is achieved by means of pixel-to-pixel manipulations of pairs of images obtained with gel-dosimeters having different isotopic composition. It is possible to place large dosimeters, detecting in such a way large dose images, because the layer geometry of dosimeters avoids sensitive variation of neutron transport due to the gel isotopic composition. Some results obtained after the last improvements of the method are reported. (Author)

  4. Evaluation of the effective dose during BNCT at TRR thermal column epithermal facility.

    Science.gov (United States)

    Jarahi, Hossein; Kasesaz, Yaser; Saleh-Koutahi, Seyed Mohsen

    2016-04-01

    An epithermal neutron beam has been designed for Boron neutron Capture Therapy (BNCT) at the thermal column of Tehran Research Reactor (TRR) recently. In this paper the whole body effective dose, as well as the equivalent doses of several organs have been calculated in this facility using MCNP4C Monte Carlo code. The effective dose has been calculated by using the absorbed doses determined for each individual organ, taking into account the radiation and tissue weighting factors. The ICRP 110 whole body male phantom has been used as a patient model. It was found that the effective dose during BNCT of a brain tumor is equal to 0.90Sv. This effective dose may induce a 4% secondary cancer risk.

  5. Risk of therapy-related leukaemia and preleukaemia after Hodgkin's disease. Relation to age, cumulative dose of alkylating agents, and time from chemotherapy

    DEFF Research Database (Denmark)

    Pedersen-Bjergaard, J.; Specht, L.; Larsen, S.O.;

    1987-01-01

    .0% (SE 3.0) at 10 years after which time there were no further cases. Calculated from cessation of therapy with alkylating agents, however, the cumulative risk curve increased steeply during the first 1-2 years then gradually levelled out and no new cases were observed beyond 7 years. With a 15-year...

  6. Thermal therapy in urologic systems: a comparison of arrhenius and thermal isoeffective dose models in predicting hyperthermic injury.

    Science.gov (United States)

    He, Xiaoming; Bhowmick, Sankha; Bischof, John C

    2009-07-01

    The Arrhenius and thermal isoeffective dose (TID) models are the two most commonly used models for predicting hyperthermic injury. The TID model is essentially derived from the Arrhenius model, but due to a variety of assumptions and simplifications now leads to different predictions, particularly at temperatures higher than 50 degrees C. In the present study, the two models are compared and their appropriateness tested for predicting hyperthermic injury in both the traditional hyperthermia (usually, 43-50 degrees C) and thermal surgery (or thermal therapy/thermal ablation, usually, >50 degrees C) regime. The kinetic parameters of thermal injury in both models were obtained from the literature (or literature data), tabulated, and analyzed for various prostate and kidney systems. It was found that the kinetic parameters vary widely, and were particularly dependent on the cell or tissue type, injury assay used, and the time when the injury assessment was performed. In order to compare the capability of the two models for thermal injury prediction, thermal thresholds for complete killing (i.e., 99% cell or tissue injury) were predicted using the models in two important urologic systems, viz., the benign prostatic hyperplasia tissue and the normal porcine kidney tissue. The predictions of the two models matched well at temperatures below 50 degrees C. At higher temperatures, however, the thermal thresholds predicted using the TID model with a constant R value of 0.5, the value commonly used in the traditional hyperthermia literature, are much lower than those predicted using the Arrhenius model. This suggests that traditional use of the TID model (i.e., R=0.5) is inappropriate for predicting hyperthermic injury in the thermal surgery regime (>50 degrees C). Finally, the time-temperature relationships for complete killing (i.e., 99% injury) were calculated and analyzed using the Arrhenius model for the various prostate and kidney systems.

  7. The effects of low dose rate irradiation and thermal aging on reactor structural alloys

    Science.gov (United States)

    Allen, T. R.; Trybus, C. L.; Cole, J. I.

    As part of the EBR-II reactor materials surveillance program, test samples of fifteen different alloys were placed into EBR-II in 1965. The surveillance (SURV) program was intended to determine property changes in reactor structural materials caused by irradiation and thermal aging. In this work, the effect of low dose rate (approximately 2 × 10 -8 dpa/s) irradiation at 380-410°C and long term thermal aging at 371°C on the properties of 20% cold worked 304 stainless steel, 420 stainless steel, Inconel X750, 304/308 stainless weld material, and 17-4 PH steel are evaluated. Doses of up to 6.8 dpa and thermal aging to 2994 days did not significantly affect the density of these alloys. The strength of 304 SS, X750, 17-4 PH, and 304/308 weld material increased with irradiation. In contrast, the strength of 420 stainless steel decreased with irradiation. Irradiation decreased the impact energy in both Inconel X750 and 17-4 PH steel. Thermal aging decreased the impact energy in 17-4 PH steel and increased the impact energy in Inconel X750. Tensile property comparisons of 304 SURV samples with 304 samples irradiated in EBR-II at a higher dose rate show that the higher dose rate samples had greater increases in strength and greater losses in ductility.

  8. Equivalence of cell survival data for radiation dose and thermal dose in ablative treatments: analysis applied to essential tremor thalamotomy by focused ultrasound and gamma knife.

    Science.gov (United States)

    Schlesinger, D; Lee, M; Ter Haar, G; Sela, B; Eames, M; Snell, J; Kassell, N; Sheehan, J; Larner, J M; Aubry, J-F

    2017-01-31

    Thermal dose and absorbed radiation dose have historically been difficult to compare because different biological mechanisms are at work. Thermal dose denatures proteins and the radiation dose causes DNA damage in order to achieve ablation. The purpose of this paper is to use the proportion of cell survival as a potential common unit by which to measure the biological effect of each procedure. Survival curves for both thermal and radiation doses have been extracted from previously published data for three different cell types. Fits of these curves were used to convert both thermal and radiation dose into the same quantified biological effect: fraction of surviving cells. They have also been used to generate and compare survival profiles from the only indication for which clinical data are available for both focused ultrasound (FUS) thermal ablation and radiation ablation: essential tremor thalamotomy. All cell types could be fitted with coefficients of determination greater than 0.992. As an illustration, survival profiles of clinical thalamotomies performed by radiosurgery and FUS are plotted on a same graph for the same metric: fraction of surviving cells. FUS and Gamma Knife have the potential to be used in combination to deliver a more effective treatment (for example, FUS may be used to debulk the main tumour mass, and radiation to treat the surrounding tumour bed). In this case, a model which compares thermal and radiation treatments is valuable in order to adjust the dose between the two.

  9. Relation between treatment efficacy and cumulative dose of alpha interferon in chronic hepatitis B. European Concerted Action on Viral Hepatitis (Eurohep)

    DEFF Research Database (Denmark)

    Krogsgaard, K; Christensen, E; Bindslev, N;

    1996-01-01

    Alpha interferon (IFN) is an established treatment of chronic hepatitis B. The effect has been shown to be dose related, recommended dose regimens being associated with a doubling of the spontaneous, baseline HBeAg to anti-HBe seroconversion rate. However, the efficacy of IFN treatment in relation...

  10. The alanine detector in BNCT dosimetry: Dose response in thermal and epithermal neutron fields

    Energy Technology Data Exchange (ETDEWEB)

    Schmitz, T., E-mail: schmito@uni-mainz.de [Institute for nuclear chemistry, Johannes Gutenberg-University, Mainz D-55128 (Germany); Bassler, N. [Department of Physics and Astronomy, Aarhus University, Ny Munkegade 120, Aarhus C, Aarhus 8000 (Denmark); Blaickner, M. [AIT Austrian Institute of Technology GmbH, Vienna A-1220 (Austria); Ziegner, M. [AIT Austrian Institute of Technology GmbH, Vienna A-1220, Austria and TU Wien, Vienna University of Technology, Vienna A-1020 (Austria); Hsiao, M. C. [Insitute of Nuclear Engineering and Science, National Tsing Hua University, Hsinchu 30013, Taiwan (China); Liu, Y. H. [Nuclear Science and Technology Development Center, National Tsing Hua University, Hsinchu 30013, Taiwan (China); Koivunoro, H. [Department of Physics, University of Helsinki, POB 64, FI-00014, Finland and HUS Medical Imaging Center, Helsinki University Central Hospital, FI-00029 HUS (Finland); Auterinen, I.; Serén, T.; Kotiluoto, P. [VTT Technical Research Centre of Finland, Espoo (Finland); Palmans, H. [National Physical Laboratory, Acoustics and Ionising Radiation Division, Teddington TW11 0LW, United Kingdom and Medical Physics Group, EBG MedAustron GmbH, Wiener Neustadt A-2700 (Austria); Sharpe, P. [National Physical Laboratory, Acoustics and Ionising Radiation Division, Teddington TW11 0LW (United Kingdom); Langguth, P. [Department of Pharmacy and Toxicology, University of Mainz, Mainz D-55128 (Germany); Hampel, G. [Institut für Kernchemie, Johannes Gutenberg-Universität, Mainz D-55128 (Germany)

    2015-01-15

    Purpose: The response of alanine solid state dosimeters to ionizing radiation strongly depends on particle type and energy. Due to nuclear interactions, neutron fields usually also consist of secondary particles such as photons and protons of diverse energies. Various experiments have been carried out in three different neutron beams to explore the alanine dose response behavior and to validate model predictions. Additionally, application in medical neutron fields for boron neutron capture therapy is discussed. Methods: Alanine detectors have been irradiated in the thermal neutron field of the research reactor TRIGA Mainz, Germany, in five experimental conditions, generating different secondary particle spectra. Further irradiations have been made in the epithermal neutron beams at the research reactors FiR 1 in Helsinki, Finland, and Tsing Hua open pool reactor in HsinChu, Taiwan ROC. Readout has been performed with electron spin resonance spectrometry with reference to an absorbed dose standard in a {sup 60}Co gamma ray beam. Absorbed doses and dose components have been calculated using the Monte Carlo codes FLUKA and MCNP. The relative effectiveness (RE), linking absorbed dose and detector response, has been calculated using the Hansen and Olsen alanine response model. Results: The measured dose response of the alanine detector in the different experiments has been evaluated and compared to model predictions. Therefore, a relative effectiveness has been calculated for each dose component, accounting for its dependence on particle type and energy. Agreement within 5% between model and measurement has been achieved for most irradiated detectors. Significant differences have been observed in response behavior between thermal and epithermal neutron fields, especially regarding dose composition and depth dose curves. The calculated dose components could be verified with the experimental results in the different primary and secondary particle fields. Conclusions: The

  11. Possibility of pure thermal sensitization in the pre-dose mechanism of the 110 deg. C TL peak of quartz

    Energy Technology Data Exchange (ETDEWEB)

    Koul, D.K., E-mail: dkkoul@barc.gov.i [Astrophysical Sciences Division, Bhabha Atomic Research Centre, Mumbai 400085 (India); Polymeris, G.S.; Tsirliganis, N.C. [R.C. ' Athena' , Cultural and Educational Technology Institute, Archaeometry Laboratory, Tsimiski 58, 67100 Xanthi (Greece); Kitis, G. [Aristotle University of Thessaloniki, Nuclear Physics Laboratory, 54124 Thessaloniki (Greece)

    2010-03-01

    The role of thermal activation in the pre-dose sensitization of the 110 deg. C TL glow peak of quartz has been hypothesized to transfer holes from reservoir centre, R, to luminescence centre, L. But, the thermal treatment has been reported to sensitize this peak, also, in an independent mode. So, a comparative analysis of the impact of thermal and pre-dose treatment on the TL properties of the 110 deg. C signal, observed by various workers, has been undertaken in this paper. Also experiments were carried out to observe thermal sensitization component at the temperatures which are used in the pre-dose sensitization measurements. The study seems to support the existence of an inherent pure thermal sensitization component in the pre-dose sensitization mechanism.

  12. An assessment of cumulative external doses from Chernobyl fallout for a forested area in Russia using the optically stimulated luminescence from quartz inclusions in bricks

    DEFF Research Database (Denmark)

    Ramzaev, V.; Bøtter-Jensen, Lars; Thomsen, Kristina Jørkov

    2008-01-01

    Optically stimulated luminescence (OSL) has been used for estimation of the accumulated doses in quartz inclusions obtained from two fired bricks, extracted in July 2004 from a building located in the forested surroundings of the recreational area Novie Bobovichi, the Bryansk Region, Russia...

  13. The influence of low dose neutron irradiation on the thermal conductivity of Allcomp carbon foam

    Energy Technology Data Exchange (ETDEWEB)

    Burchell, Timothy D. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Porter, Wallace D. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); McDuffee, Joel Lee [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2016-03-01

    Oak Ridge National Laboratory was contracted via a Work for Others Agreement with Allcomp Inc. (NFE-14-05011-MSOF: Carbon Foam for Beam Stop Applications ) to determine the influence of low irradiation dose on the thermal conductivity of Allcomp Carbon Foam. Samples (6 mm dia. x 5 mm thick) were successfully irradiated in a rabbit capsule in a hydraulic tube in the target region of the High Flux Isotope Reactor at the Oak Ridge National Laboratory. The specimens were irradiated at Tirr = 747.5 C to a neutron damage dose of 0.2 dpa. There is a small dimensional and volume shrinkage and the mass and density appear reduced (we would expect density to increase as volume reduces at constant mass). The small changes in density, dimensions or volume are not of concern. At 0.2 dpa the irradiation shrinkage rate difference between the glassy carbon skeleton and the CVD coating was not sufficient to cause a large enough irradiation-induced strain to create any mechanical degradation. Similarly differential thermal expansion was not a problem. It appears that only the thermal conductivity was affected by 0.2 dpa. For the intended application conditions, i.e. @ 400 C and 0 DPA (start- up) the foam thermal conductivity is about 57 W/m.K and at 700 C and 0.2 DPA (end of life) the foam thermal conductivity is approx. 30.7 W/m.K. The room temp thermal conductivity drops from 100-120 W/m.K to approximately 30 W/m.K after 0.2 dpa of neutron irradiation.

  14. The Soft Cumulative Constraint

    CERN Document Server

    Petit, Thierry

    2009-01-01

    This research report presents an extension of Cumulative of Choco constraint solver, which is useful to encode over-constrained cumulative problems. This new global constraint uses sweep and task interval violation-based algorithms.

  15. Measurements of gamma dose and thermal neutron fluence in phantoms exposed to a BNCT epithermal beam with TLD-700.

    Science.gov (United States)

    Gambarini, G; Magni, D; Regazzoni, V; Borroni, M; Carrara, M; Pignoli, E; Burian, J; Marek, M; Klupak, V; Viererbl, L

    2014-10-01

    Gamma dose and thermal neutron fluence in a phantom exposed to an epithermal neutron beam for boron neutron capture therapy (BNCT) can be measured by means of a single thermoluminescence dosemeter (TLD-700). The method exploits the shape of the glow curve (GC) and requires the gamma-calibration GC (to obtain gamma dose) and the thermal-neutron-calibration GC (to obtain neutron fluence). The method is applicable for BNCT dosimetry in case of epithermal neutron beams from a reactor because, in most irradiation configurations, thermal neutrons give a not negligible contribution to the TLD-700 GC. The thermal neutron calibration is not simple, because of the impossibility of having thermal neutron fields without gamma contamination, but a calibration method is here proposed, strictly bound to the method itself of dose separation.

  16. UBIQUITOUS POLLUTANTS FROM CUMULATIVE ...

    Science.gov (United States)

    The occurrence of pharmaceuticals and personal care products (PPCPS) as environmental pollutants is a multifaceted issue whose scope continues to become better delineated since the escalation of concerted attention beginning in the 1980s. PPCPs typically occur as trace environmental pollutants (primarily in surface but also in ground waters) as a result of their widespread, continuous, combined usage in a broad range of human and veterinary therapeutic activities and practices. With respect to the risk-assessment paradigm, the growing body of published work has focused primarily on the origin and occurrence of these substances. Comparatively less is known about human and ecological exposure, and even less about the known or even potential hazards associated with exposure to these anthropogenic substances, many of which are highly bioactive. The continually growing, worldwide importance of freshwater resources underscores the need for ensuring that any aggregate or cumulative impacts on water supplies and resultant potential for human or ecological exposure be minimized. This has prompted the more recent investigations on waste treatment processes for one of the major sources of environmental disposition, namely sewage. Despite the paucity of health effects data for long-term, simultaneous exposure to multiple xenobiotics (particularly PPCPS) at low doses (a major toxicological issue that can be described by the

  17. Cumulative mortality rates in Aedes polynesiensis after feeding on polynesian Wuchereria bancrofti carriers treated with single doses of ivermectin, diethylcarbamazine and placebo.

    Science.gov (United States)

    Cartel, J L; Sechan, Y; Spiegel, A; Nguyen, L; Barbazan, P; Martin, P M; Roux, J F

    1991-12-01

    During a therapeutic trial, batches of 672 to 1979 laboratory-bred Aedes polynesiensis, the mosquito vector of lymphatic filariasis in French Polynesia, were fed on Wuchereria bancrofti carriers one, three and six months after they had been treated with either single doses of ivermectin at 100 mcg/kg, diethylcarbamazine (DEC) at 3 and 6 mg/kg or placebo. High mortality rates were observed during the 15-day period following the blood-meal in mosquitoes fed on carriers treated with microfilaricidal drugs and were significantly higher in mosquitoes fed on carriers treated with ivermectin than in those fed on carriers treated with DEC. Though its intensity decreased with the passage of time, the phenomenon was observed in mosquitoes fed on carriers up to six months after treatment, especially in those fed on carriers treated with ivermectin. By decreasing the number of mosquitoes able to transmit the infection, this lethal effect on Ae. polynesiensis might represent an additional advantage of ivermectin in lymphatic filariasis control programs.

  18. Dose response, thermal stability and optical bleaching of the 310 degrees C isothermal TL signal in quartz

    DEFF Research Database (Denmark)

    Jain, Mayank; Duller, G.A.T.; Wintle, A.G.

    2007-01-01

    degrees C TL peak. Bleaching with a solar simulator reduces both parts of the ITL signal to a low, but non-zero level in a few thousand seconds. This result is supported by an equivalent dose estimate oil a modern river sample from Zambia of 11 +/- 2 Gy. This combination of low residual dose and high......, thermal stability and the effects of optical bleaching. The (0-5s) signal shows all order of magnitude higher for saturation level with laboratory dose than the optically stimulated luminescence (OSL) signal, and has a thermal stability that is very sintilar to published values for the OSL or the 325...

  19. Experimental verification of improved depth-dose distribution using hyper-thermal neutron incidence in neutron capture therapy

    Science.gov (United States)

    Sakurai, Yoshinori; Kobayashi, Tooru

    2001-01-01

    We have proposed the utilization of `hyper-thermal neutrons' for neutron capture therapy (NCT) from the viewpoint of the improvement in the dose distribution in a human body. In order to verify the improved depth-dose distribution due to hyper-thermal neutron incidence, two experiments were carried out using a test-type hyper-thermal neutron generator at a thermal neutron irradiation field in Kyoto University Reactor (KUR), which is actually utilized for NCT clinical irradiation. From the free-in-air experiment for the spectrum-shift characteristics, it was confirmed that the hyper-thermal neutrons of approximately 860 K at maximum could be obtained by the generator. From the phantom experiment, the improvement effect and the controllability for the depth-dose distribution were confirmed. For example, it was found that the relative neutron depth-dose distribution was about 1 cm improved with the 860 K hyper-thermal neutron incidence, compared to the normal thermal neutron incidence.

  20. Experimental verification of improved depth-dose distribution using hyper-thermal neutron incidence in neutron capture therapy.

    Science.gov (United States)

    Sakurai, Y; Kobayashi, T

    2001-01-01

    We have proposed the utilization of 'hyper-thermal neutrons' for neutron capture therapy (NCT) from the viewpoint of the improvement in the dose distribution in a human body. In order to verify the improved depth-dose distribution due to hyper-thermal neutron incidence, two experiments were carried out using a test-type hyper-thermal neutron generator at a thermal neutron irradiation field in Kyoto University Reactor (KUR), which is actually utilized for NCT clinical irradiation. From the free-in-air experiment for the spectrum-shift characteristics, it was confirmed that the hyper-thermal neutrons of approximately 860 K at maximum could be obtained by the generator. From the phantom experiment, the improvement effect and the controllability for the depth-dose distribution were confirmed. For example, it was found that the relative neutron depth-dose distribution was about 1 cm improved with the 860 K hyper-thermal neutron incidence, compared to the normal thermal neutron incidence.

  1. Cumulant expansions for atmospheric flows

    CERN Document Server

    Ait-Chaalal, Farid; Meyer, Bettina; Marston, J B

    2015-01-01

    The equations governing atmospheric flows are nonlinear, and consequently the hierarchy of cumulant equations is not closed. But because atmospheric flows are inhomogeneous and anisotropic, the nonlinearity may manifests itself only weakly through interactions of mean fields with disturbances such as thermals or eddies. In such situations, truncations of the hierarchy of cumulant equations hold promise as a closure strategy. We review how truncations at second order can be used to model and elucidate the dynamics of turbulent atmospheric flows. Two examples are considered. First, we study the growth of a dry convective boundary layer, which is heated from below, leading to turbulent upward energy transport and growth of the boundary layer. We demonstrate that a quasilinear truncation of the equations of motion, in which interactions of disturbances among each other are neglected but interactions with mean fields are taken into account, can successfully capture the growth of the convective boundary layer. Seco...

  2. New topology for soft switching converters: realization of a 2 kW converter which can operate under cumulated radiation doses comprised between 1 and 10 mega-rads; Nouvelle topologie de convertisseur a commutation douce: realisation d'un convertisseur 2 kW fonctionnant pour des doses de rayonnement cumulees comprises entre 1 et 10 Mega-rads

    Energy Technology Data Exchange (ETDEWEB)

    Marceau, M. [CEA/Saclay, Dept. d' Electronique et d' Instrumentation Nucleaire (DEIN), 91 - Gif-sur-Yvette (France); Huillet, H.; Ploquin, D. [Gaia Converter, 33 - Merignac (France)

    1998-11-01

    This paper presents a new topology of a patented power converter. This topology applies to DC-DC converters with soft switching operation. The power density reached is of about 4000 W/liter and the efficiency is greater than 90%. This converter, devoted to nuclear applications, has been dimensioned to be able to operate under cumulated radiation doses greater than 1 Mega rads. A functioning principle scheme and a brief description of the topology is reported in this short paper. (J.S.)

  3. Increasing signal intensity within the dentate nucleus and globus pallidus on unenhanced T1W magnetic resonance images in patients with relapsing-remitting multiple sclerosis: correlation with cumulative dose of a macrocyclic gadolinium-based contrast agent, gadobutrol

    Energy Technology Data Exchange (ETDEWEB)

    Stojanov, Dragan A. [University of Nis, Faculty of Medicine, Nis (Serbia); Clinical Center Nis, Center for Radiology, Nis (Serbia); Aracki-Trenkic, Aleksandra [Clinical Center Nis, Center for Radiology, Nis (Serbia); Vojinovic, Slobodan; Ljubisavljevic, Srdjan [University of Nis, Faculty of Medicine, Nis (Serbia); Clinical Center Nis, Clinic for Neurology, Nis (Serbia); Benedeto-Stojanov, Daniela [University of Nis, Faculty of Medicine, Nis (Serbia)

    2016-03-15

    To evaluate correlation between cumulative dose of gadobutrol and signal intensity (SI) within dentate nucleus and globus pallidus on unenhanced T1-weighted images in patients with relapsing-remitting multiple sclerosis (RRMS). Dentate nucleus-to-pons and globus pallidus-to-thalamus SI ratios, and renal and liver functions, were evaluated after multiple intravenous administrations of 0.1 mmol/kg gadobutrol at 27, 96-98, and 168 weeks. We compared SI ratios based on the number of administrations, total amount of gadobutrol administered, and time between injections. Globus pallidus-to-thalamus (p = 0.025) and dentate nucleus-to-pons (p < 0.001) SI ratios increased after multiple gadobutrol administrations, correlated with the number of administrations (ρ = 0.263, p = 0.046, respectively) and depended on the length of administration (p = 0.017, p = 0.037, respectively). Patients receiving gadobutrol at 27 weeks showed the greatest increase in both SI ratios (p = 0.006; p = 0.014, respectively, versus 96-98 weeks). GGT increased at the end of the study (p = 0.004). In patients with RRMS, SI within the dentate nucleus and globus pallidus increased on unenhanced T1-weighted images after multiple gadobutrol injections. Administration of the same total amount of gadobutrol over a shorter period caused greater SI increase. (orig.)

  4. Defect annealing and thermal desorption of deuterium in low dose HFIR neutron-irradiated tungsten

    Energy Technology Data Exchange (ETDEWEB)

    Masashi Shimada; M. Hara; T. Otsuka; Y. Oya; Y. Hatano

    2014-05-01

    Accurately estimating tritium retention in plasma facing components (PFCs) and minimizing its uncertainty are key safety issues for licensing future fusion power reactors. D-T fusion reactions produce 14.1 MeV neutrons that activate PFCs and create radiation defects throughout the bulk of the material of these components. Recent studies show that tritium migrates and is trapped in bulk (>> 10 µm) tungsten beyond the detection range of nuclear reaction analysis technique [1-2], and thermal desorption spectroscopy (TDS) technique becomes the only established diagnostic that can reveal hydrogen isotope behavior in in bulk (>> 10 µm) tungsten. Radiation damage and its recovery mechanisms in neutron-irradiated tungsten are still poorly understood, and neutron-irradiation data of tungsten is very limited. In this paper, systematic investigations with repeated plasma exposures and thermal desorption are performed to study defect annealing and thermal desorption of deuterium in low dose neutron-irradiated tungsten. Three tungsten samples (99.99 at. % purity from A.L.M.T. Co., Japan) irradiated at High Flux Isotope Reactor at Oak Ridge National Laboratory were exposed to high flux (ion flux of (0.5-1.0)x1022 m-2s-1 and ion fluence of 1x1026 m-2) deuterium plasma at three different temperatures (100, 200, and 500 °C) in Tritium Plasma Experiment at Idaho National Laboratory. Subsequently, thermal desorption spectroscopy (TDS) was performed with a ramp rate of 10 °C/min up to 900 °C, and the samples were annealed at 900 °C for 0.5 hour. These procedures were repeated three (for 100 and 200 °C samples) and four (for 500 °C sample) times to uncover damage recovery mechanisms and its effects on deuterium behavior. The results show that deuterium retention decreases approximately 90, 75, and 66 % for 100, 200, and 500 °C, respectively after each annealing. When subjected to the same TDS recipe, the desorption temperature shifts from 800 °C to 600 °C after 1st annealing

  5. Evaluation of HIFU-induced lesion region using temperature threshold and equivalent thermal dose methods

    Science.gov (United States)

    Chang, Shihui; Xue, Fanfan; Zhou, Wenzheng; Zhang, Ji; Jian, Xiqi

    2017-03-01

    Usually, numerical simulation is used to predict the acoustic filed and temperature distribution of high intensity focused ultrasound (HIFU). In this paper, the simulated lesion volumes obtained by temperature threshold (TRT) 60 °C and equivalent thermal dose (ETD) 240 min were compared with the experimental results which were obtained by animal tissue experiment in vitro. In the simulation, the calculated model was established according to the vitro tissue experiment, and the Finite Difference Time Domain (FDTD) method was used to calculate the acoustic field and temperature distribution in bovine liver by the Westervelt formula and Pennes bio-heat transfer equation, and the non-linear characteristics of the ultrasound was considered. In the experiment, the fresh bovine liver was exposed for 8s, 10s, 12s under different power conditions (150W, 170W, 190W, 210W), and the exposure was repeated 6 times under the same dose. After the exposures, the liver was sliced and photographed every 0.2mm, and the area of the lesion region in every photo was calculated. Then, every value of the areas was multiplied by 0.2mm, and summed to get the approximation volume of the lesion region. The comparison result shows that the lesion volume of the region calculated by TRT 60 °C in simulation was much closer to the lesion volume obtained in experiment, and the volume of the region above 60 °C was larger than the experimental results, but the volume deviation was not exceed 10%. The volume of the lesion region calculated by ETD 240 min was larger than that calculated by TRT 60 °C in simulation, and the volume deviations were ranged from 4.9% to 23.7%.

  6. Cumulative fatigue damage models

    Science.gov (United States)

    Mcgaw, Michael A.

    1988-01-01

    The problem of calculating expected component life under fatigue loading conditions is complicated by the fact that component loading histories contain, in many cases, cyclic loads of widely varying amplitudes. In such a case a cumulative damage model is required, in addition to a fatigue damage criterion, or life relationship, in order to compute the expected fatigue life. The traditional cumulative damage model used in design is the linear damage rule. This model, while being simple to use, can yield grossly unconservative results under certain loading conditions. Research at the NASA Lewis Research Center has led to the development of a nonlinear cumulative damage model, named the double damage curve approach (DDCA), that has greatly improved predictive capability. This model, which considers the life (or loading) level dependence of damage evolution, was applied successfully to two polycrystalline materials, 316 stainless steel and Haynes 188. The cumulative fatigue behavior of the PWA 1480 single-crystal material is currently being measured to determine the applicability of the DDCA for this material.

  7. Cumulative radiation exposure in children with cystic fibrosis.

    LENUS (Irish Health Repository)

    O'Reilly, R

    2010-02-01

    This retrospective study calculated the cumulative radiation dose for children with cystic fibrosis (CF) attending a tertiary CF centre. Information on 77 children with a mean age of 9.5 years, a follow up time of 658 person years and 1757 studies including 1485 chest radiographs, 215 abdominal radiographs and 57 computed tomography (CT) scans, of which 51 were thoracic CT scans, were analysed. The average cumulative radiation dose was 6.2 (0.04-25) mSv per CF patient. Cumulative radiation dose increased with increasing age and number of CT scans and was greater in children who presented with meconium ileus. No correlation was identified between cumulative radiation dose and either lung function or patient microbiology cultures. Radiation carries a risk of malignancy and children are particularly susceptible. Every effort must be made to avoid unnecessary radiation exposure in these patients whose life expectancy is increasing.

  8. Cumulative Timers for Microprocessors

    Science.gov (United States)

    Battle, John O.

    2007-01-01

    It has been proposed to equip future microprocessors with electronic cumulative timers, for essentially the same reasons for which land vehicles are equipped with odometers (total-distance-traveled meters) and aircraft are equipped with Hobbs meters (total-engine-operating time meters). Heretofore, there has been no way to determine the amount of use to which a microprocessor (or a product containing a microprocessor) has been subjected. The proposed timers would count all microprocessor clock cycles and could only be read by means of microprocessor instructions but, like odometers and Hobbs meters, could never be reset to zero without physically damaging the chip.

  9. Cumulative Vehicle Routing Problems

    OpenAIRE

    Kara, &#;mdat; Kara, Bahar Yeti&#;; Yeti&#;, M. Kadri

    2008-01-01

    This paper proposes a new objective function and corresponding formulations for the vehicle routing problem. The new cost function defined as the product of the distance of the arc and the flow on that arc. We call a vehicle routing problem with this new objective function as the Cumulative Vehicle Routing Problem (CumVRP). Integer programming formulations with O(n2) binary variables and O(n2) constraints are developed for both collection and delivery cases. We show that the CumVRP is a gener...

  10. Simulations of thermally transferred OSL signals in quartz: Accuracy and precision of the protocols for equivalent dose evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Pagonis, Vasilis, E-mail: vpagonis@mcdaniel.edu [Physics Department, McDaniel College, Westminster, MD 21157 (United States); Adamiec, Grzegorz [Silesian University of Technology, Institute of Physics, GADAM Centre of Excellence, ul. Krzywoustego 2, 44-100 Gliwice (Poland); Athanassas, C. [Laboratory of Archaeometry, Institute of Materials Science, N.C.S.R. ' Demokritos' , Aghia Paraskevi, Athens153 10 (Greece); Chen Reuven [Raymond and Beverly Sackler School of Physics and Astronomy, Tel-Aviv University, Tel-Aviv 69978 (Israel); Baker, Atlee; Larsen, Meredith; Thompson, Zachary [Physics Department, McDaniel College, Westminster, MD 21157 (United States)

    2011-06-15

    Highlights: > This paper presents extensive numerical simulations of the ReSAR protocol for luminescence dating. > We simulate several experimental versions of the ReSAR protocol and compare their relative accuracy and precision. > Simulations are carried out using a recently published kinetic model for quartz, consisting of 11 energy levels. > Natural doses above 400 Gy are underestimated in the protocols. > Possible sources of this underestimation are investigated. - Abstract: Thermally-transferred optically stimulated luminescence (TT-OSL) signals in sedimentary quartz have been the subject of several recent studies, due to the potential shown by these signals to increase the range of luminescence dating by an order of magnitude. Based on these signals, a single aliquot protocol termed the ReSAR protocol has been developed and tested experimentally. This paper presents extensive numerical simulations of this ReSAR protocol. The purpose of the simulations is to investigate several aspects of the ReSAR protocol which are believed to cause difficulties during application of the protocol. Furthermore, several modified versions of the ReSAR protocol are simulated, and their relative accuracy and precision are compared. The simulations are carried out using a recently published kinetic model for quartz, consisting of 11 energy levels. One hundred random variants of the natural samples were generated by keeping the transition probabilities between energy levels fixed, while allowing simultaneous random variations of the concentrations of the 11 energy levels. The relative intrinsic accuracy and precision of the protocols are simulated by calculating the equivalent dose (ED) within the model, for a given natural burial dose of the sample. The complete sequence of steps undertaken in several versions of the dating protocols is simulated. The relative intrinsic precision of these techniques is estimated by fitting Gaussian probability functions to the resulting simulated

  11. Cumulative environmental effects. Summary

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2012-07-01

    This report presents a compilation of knowledge about the state of the environment and human activity in the Norwegian part of the North Sea and Skagerrak. The report gives an overview of pressures and impacts on the environment from normal activity and in the event of accidents. This is used to assess the cumulative environmental effects, which factors have most impact and where the impacts are greatest, and to indicate which problems are expected to be most serious in the future. The report is intended to provide relevant information that can be used in the management of the marine area in the future. It also provides input for the identification of environmental targets and management measures for the North Sea and Skagerrak.(Author)

  12. Feasibility of real-time MR thermal dose mapping for predicting radiofrequency ablation outcome in the myocardium in vivo.

    Science.gov (United States)

    Toupin, Solenn; Bour, Pierre; Lepetit-Coiffé, Matthieu; Ozenne, Valéry; Denis de Senneville, Baudouin; Schneider, Rainer; Vaussy, Alexis; Chaumeil, Arnaud; Cochet, Hubert; Sacher, Frédéric; Jaïs, Pierre; Quesson, Bruno

    2017-01-25

    Clinical treatment of cardiac arrhythmia by radiofrequency ablation (RFA) currently lacks quantitative and precise visualization of lesion formation in the myocardium during the procedure. This study aims at evaluating thermal dose (TD) imaging obtained from real-time magnetic resonance (MR) thermometry on the heart as a relevant indicator of the thermal lesion extent. MR temperature mapping based on the Proton Resonance Frequency Shift (PRFS) method was performed at 1.5 T on the heart, with 4 to 5 slices acquired per heartbeat. Respiratory motion was compensated using navigator-based slice tracking. Residual in-plane motion and related magnetic susceptibility artifacts were corrected online. The standard deviation of temperature was measured on healthy volunteers (N = 5) in both ventricles. On animals, the MR-compatible catheter was positioned and visualized in the left ventricle (LV) using a bSSFP pulse sequence with active catheter tracking. Twelve MR-guided RFA were performed on three sheep in vivo at various locations in left ventricle (LV). The dimensions of the thermal lesions measured on thermal dose images, on 3D T1-weighted (T1-w) images acquired immediately after the ablation and at gross pathology were correlated. MR thermometry uncertainty was 1.5 °C on average over more than 96% of the pixels covering the left and right ventricles, on each volunteer. On animals, catheter repositioning in the LV with active slice tracking was successfully performed and each ablation could be monitored in real-time by MR thermometry and thermal dosimetry. Thermal lesion dimensions on TD maps were found to be highly correlated with those observed on post-ablation T1-w images (R = 0.87) that also correlated (R = 0.89) with measurements at gross pathology. Quantitative TD mapping from real-time rapid CMR thermometry during catheter-based RFA is feasible. It provides a direct assessment of the lesion extent in the myocardium with precision in the range of one

  13. Thermal activation and radiation quenching characteristics and their application to the pre-dose dating of porcelain

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    The pre-dose technique is important for thermoluminescence (TL) dating of porcelain. The principle of pre-dose dating is based on two characteristics: thermal activation and radiation quenching of the porcelain. Based on these principles, two measurement methods, "the activation method" and "the quenching method", respectively, have been developed for evaluation of the porcelain paleodose. The paleodose values obtained are the same for the ages in the range of 100―1000 a BP for porcelains measured by these two methods. But for dating at lower age limits (less than 100 a BP), the activation method is more accurate; conversely, at higher age limits (greater than 1000 a BP) the quenching method is more accurate. In addition, two specific calculating methods are described for a few porce-lains having anomalous activation and quenching characteristics that make these two methods invalid.

  14. Thermal activation and radiation quenching characteristics and their application to the pre-dose dating of porcelain

    Institute of Scientific and Technical Information of China (English)

    WANG WeiDa

    2009-01-01

    The pre-dose technique is important for thermoluminescence (TL) dating of porcelain. The principle of pre-dose dating is based on two characteristics: thermal activation and radiation quenching of the porcelain. Based on these principles, two measurement methods, "the activation method" and "the quenching method", respectively, have been developed for evaluation of the porcelain paleodose. The paleodose values obtained are the same for the ages in the range of 100--1000 a BP for porcelains measured by these two methods. But for dating at lower age limits (less than 100 a BP), the activation method is more accurate; conversely, at higher age limits (greater than 1000 a BP) the quenching method is more accurate. In addition, two specific calculating methods are described for a few porce-lains having anomalous activation and quenching characteristics that make these two methods invalid.

  15. Pure thermal sensitisation and pre-dose effect of OSL in both unfired and annealed quartz samples

    Energy Technology Data Exchange (ETDEWEB)

    Oniya, Ebenezer O., E-mail: ebenezer.oniya@aaua.edu.ng [Physics and Electronics Department, Adekunle Ajasin University, 342111 Akungba Akoko (Nigeria); Polymeris, George S. [Institute of Nuclear Sciences, Ankara University, Beşevler 06100, Ankara (Turkey); Jibiri, Nnamdi N. [Department of Physics, University of Ibadan, Ibadan (Nigeria); Tsirliganis, Nestor C. [Department of Archaeometry and Physicochemical Measurements, R.C. ‘Athena’, P.O. Box 159, Kimmeria University Campus, 67100 Xanthi (Greece); Babalola, Israel A. [Department of Physics, University of Ibadan, Ibadan (Nigeria); Kitis, George [Nuclear Physics Laboratory, Department of Physics, Aristotle University of Thessaloniki, 54124 Thessaloniki (Greece)

    2017-06-01

    The sensitisation of quartz has attracted much attention since its thorough understanding is important in luminescence studies and dating applications. The present investigation examines the influence of pure thermal activation and predose treatments on the sensitisation of different components of linearly modulated optically stimulated luminescence (LM-OSL) measured at room temperature (RT) thereby eliminating undesired thermal quenching effects. Annealed and unfired quartz samples from Nigeria were used. The OSL measurements were carried out using an automated RISØTL/OSL reader (model-TL/OSL–DA–15). A new approach was adopted to match each of the resolved components of the RT-LM-OSL to respective thermoluminescence (TL) peaks that share the same electron trap and recombination centers. Pure thermal activation and pre-dose treatments respectively affect the sensitisation of all the components of the RT-LM-OSL in a similar manner as the one reported for the 110 °C TL peak but without thermal quenching contributions. Component C4 in annealed samples that was identified to share the same electron trap and recombination centers with the 110 °C TL peak was also proved appropriate for RT-LM-OSL, instead of the initial part of the continuous wave (CW) OSL signal, thus the methods can serve as complementary dating methods.

  16. Maintenance hemodialysis patients have high cumulative radiation exposure.

    LENUS (Irish Health Repository)

    Kinsella, Sinead M

    2010-10-01

    Hemodialysis is associated with an increased risk of neoplasms which may result, at least in part, from exposure to ionizing radiation associated with frequent radiographic procedures. In order to estimate the average radiation exposure of those on hemodialysis, we conducted a retrospective study of 100 patients in a university-based dialysis unit followed for a median of 3.4 years. The number and type of radiological procedures were obtained from a central radiology database, and the cumulative effective radiation dose was calculated using standardized, procedure-specific radiation levels. The median annual radiation dose was 6.9 millisieverts (mSv) per patient-year. However, 14 patients had an annual cumulative effective radiation dose over 20 mSv, the upper averaged annual limit for occupational exposure. The median total cumulative effective radiation dose per patient over the study period was 21.7 mSv, in which 13 patients had a total cumulative effective radiation dose over 75 mSv, a value reported to be associated with a 7% increased risk of cancer-related mortality. Two-thirds of the total cumulative effective radiation dose was due to CT scanning. The average radiation exposure was significantly associated with the cause of end-stage renal disease, history of ischemic heart disease, transplant waitlist status, number of in-patient hospital days over follow-up, and death during the study period. These results highlight the substantial exposure to ionizing radiation in hemodialysis patients.

  17. Effect of water chemistry upsets on the dynamics of corrective reagent dosing systems at thermal power stations

    Science.gov (United States)

    Voronov, V. N.; Yegoshina, O. V.; Bolshakova, N. A.; Yarovoi, V. O.; Latt, Aie Min

    2016-12-01

    Typical disturbances in the dynamics of a corrective reagent dosing system under unsteady-state conditions during the unsatisfactory operation of a chemical control system with some water chemistry upsets at thermal and nuclear power stations are considered. An experimental setup representing a physical model for the water chemistry control system is described. The two disturbances, which are most frequently encountered in water chemistry control practice, such as a breakdown or shutdown of temperature compensation during pH measurement and an increase in the heat-transfer fluid flow rate, have been modeled in the process of study. The study of the effect produced by the response characteristics of chemical control analyzers on the operation of a reagent dosing system under unsteady-state conditions is important for the operative control of a water chemistry regime state. The effect of temperature compensation during pH measurement on the dynamics of an ammonia-dosing system in the manual and automatic cycle chemistry control modes has been studied. It has been demonstrated that the reading settling time of a pH meter in the manual ammonia- dosing mode grows with a breakdown in temperature compensation and a simultaneous increase in the temperature of a heat-transfer fluid sample. To improve the efficiency of water chemistry control, some systems for the quality control of a heat-transfer fluid by a chemical parameter with the obligatory compensation of a disturbance in its flow rate have been proposed for use. Experimental results will possibly differ from industrial data due to a great length of sampling lines. For this reason, corrective reagent dosing systems must be adapted to the conditions of a certain power-generating unit in the process of their implementation.

  18. Lattice QCD results on cumulant ratios at freeze-out

    CERN Document Server

    Karsch, Frithjof

    2016-01-01

    Ratios of cumulants of net proton-number fluctuations measured by the STAR Collaboration show strong deviations from a skellam distribution, which should describe thermal properties of cumulant ratios, if proton-number fluctuations are generated in equilibrium and a hadron resonance gas (HRG) model would provide a suitable description of thermodynamics at the freeze-out temperature. We present some results on sixth order cumulants entering the calculation of the QCD equation of state at non-zero values of the baryon chemical potential (mu_B) and discuss limitations on the applicability of HRG thermodynamics deduced from a comparison between QCD and HRG model calculations of cumulants of conserved charge fluctuations. We show that basic features of the $\\mu_B$-dependence of skewness and kurtosis ratios of net proton-number fluctuations measured by the STAR Collaboration resemble those expected from a O(mu_B^2) QCD calculation of the corresponding net baryon-number cumulant ratios.

  19. Dose dependence and thermal stability of the thermoluminescence emission in inorganic dust from mint and camomile

    Energy Technology Data Exchange (ETDEWEB)

    Gomez-Ros, J.M. [CIEMAT, Av. Complutense 22, 28040 Madrid (Spain)]. E-mail: jm.gomezros@ciemat.es; Furetta, C. [Inst. de Ciencias Nucleares UNAM, P.O. Box 70-543, 04510 Mexico DF (Mexico); Cruz-Zaragoza, E. [Inst. de Ciencias Nucleares UNAM, P.O. Box 70-543, 04510 Mexico DF (Mexico); Lis, M. [CIEMAT, Av. Complutense 22, 28040 Madrid (Spain); Torres, A. [Inst. de Ciencias Nucleares UNAM, P.O. Box 70-543, 04510 Mexico DF (Mexico); Monsivais, G. [Inst. de Ciencias Nucleares UNAM, P.O. Box 70-543, 04510 Mexico DF (Mexico)

    2006-10-15

    The inorganic phase extracted from mint and camomile samples obtained from commercial products in Mexico was selected according to different grain sizes and exposed to {sup 60}Co gamma radiation at different doses in the range 0.5-12 kGy. Thermoluminescence (TL) glow curves show a single broad peak, centred around 175 deg. C for prompt readouts. X-ray diffraction analysis indicates the inorganic dust is mainly composed by quartz, Na,K-feldspars and amphiboles, which use to be characterized by TL emissions associated to continuous distribution of trapping centres. The high fading of the TL signal during the first days of storage at room temperature can be related to the shallowest part of the distribution while the deepest traps originate the asymptotic behaviour for longer storage times. The TL intensity also increases significatively with the grain size, being linear with the absorbed dose at least up to 10 kGy.

  20. Simulation of radiation dose distribution and thermal analysis for the bulk shielding of an optimized molten salt reactor

    Institute of Scientific and Technical Information of China (English)

    张志宏; 夏晓彬; 蔡军; 王建华; 李长园; 葛良全; 张庆贤

    2015-01-01

    The Chinese Academy of Science has launched a thorium-based molten-salt reactor (TMSR) research project with a mission to research and develop a fission energy system of the fourth generation. The TMSR project intends to construct a liquid fuel molten-salt reactor (TMSR-LF), which uses fluoride salt as both the fuel and coolant, and a solid fuel molten-salt reactor (TMSR-SF), which uses fluoride salt as coolant and TRISO fuel. An optimized 2 MWth TMSR-LF has been designed to solve major technological challenges in the Th-U fuel cycle. Preliminary conceptual shielding design has also been performed to develop bulk shielding. In this study, the radiation dose and temperature distribution of the shielding bulk due to the core were simulated and analyzed by performing Monte Carlo simulations and computational fluid dynamics (CFD) analysis. The MCNP calculated dose rate and neutron and gamma spectra indicate that the total dose rate due to the core at the external surface of the concrete wall was 1.91 µSv/h in the radial direction, 1.16 µSv/h above and 1.33 µSv/h below the bulk shielding. All the radiation dose rates due to the core were below the design criteria. Thermal analysis results show that the temperature at the outermost surface of the bulk shielding was 333.86 K, which was below the required limit value. The results indicate that the designed bulk shielding satisfies the radiation shielding requirements for the 2 MWth TMSR-LF.

  1. Cumulate Fragments in Silicic Ignimbrites

    Science.gov (United States)

    Bachmann, O.; Ellis, B. S.; Wolff, J.

    2014-12-01

    Increasingly, studies are concluding that silicic ignimbrites are the result of the amalgamation of multiple discrete magma batches. Yet the existence of discrete batches presents a conundrum for magma generation and storage; if silicic magma batches are not generated nearly in situ in the upper crust, they must traverse, and reside within, a thermally hostile environment with large temperature gradients, resulting in low survivability in their shallow magmatic hearths. The Snake River Plain (Idaho, USA) is a type example of this 'multi-batch' assembly with ignimbrites containing multiple populations of pyroxene crystals, glass shards, and crystal aggregates. The ubiquitous crystal aggregates hint at a mechanism to facilitate the existence of multiple, relatively small batches of rhyolite in the upper crust. These aggregates contain the same plagioclase, pyroxene, and oxide mineral compositions as single phenocrysts of the same minerals in their host rocks, but they have significantly less silicic bulk compositions and lack quartz and sanidine, which occur as single phenocrysts in the deposits. This implies significant crystallization followed by melt extraction from mushy reservoir margins. The extracted melt then continues to evolve (crystallizing sanidine and quartz) while the melt-depleted margins provide an increasingly rigid and refractory network segregating the crystal-poor batches of magma. The hot, refractory, margins insulate the crystal-poor lenses, allowing (1) extended residence in the upper crust, and (2) preservation of chemical heterogeneities among batches. In contrast, systems that produce cumulates richer in low-temperature phases (quartz, K-feldspars, and/or biotite) favour remelting upon recharge, leading to less segregation of eruptible melt pockets and the formation of gradationally zoned ignimbrites. The occurrence of similar crystal aggregates from a variety of magmatic lineages suggests the generality of this process.

  2. Defect annealing and thermal desorption of deuterium in low dose HFIR neutron-irradiated tungsten

    Energy Technology Data Exchange (ETDEWEB)

    Shimada, Masashi, E-mail: Masashi.Shimada@inl.gov [Fusion Safety Program, Idaho National Laboratory, Idaho Falls, ID (United States); Hara, Masanori [Hydrogen Isotope Research Center, University of Toyama, Toyama (Japan); Otsuka, Teppei [Kyushu University, Interdisciplinary Graduate School of Engineering Science, Higashi-ku, Fukuoka (Japan); Oya, Yasuhisa [Radioscience Research Laboratory, Faculty of Science, Shizuoka University, Shizuoka (Japan); Hatano, Yuji [Hydrogen Isotope Research Center, University of Toyama, Toyama (Japan)

    2015-08-15

    Three tungsten samples irradiated at High Flux Isotope Reactor at Oak Ridge National Laboratory were exposed to deuterium plasma (ion fluence of 1 × 10{sup 26} m{sup −2}) at three different temperatures (100, 200, and 500 °C) in Tritium Plasma Experiment at Idaho National Laboratory. Subsequently, thermal desorption spectroscopy was performed with a ramp rate of 10 °C min{sup −1} up to 900 °C, and the samples were annealed at 900 °C for 0.5 h. These procedures were repeated three times to uncover defect-annealing effects on deuterium retention. The results show that deuterium retention decreases approximately 70% for at 500 °C after each annealing, and radiation damages were not annealed out completely even after the 3rd annealing. TMAP modeling revealed the trap concentration decreases approximately 80% after each annealing at 900 °C for 0.5 h.

  3. Electrical properties of high-dose nitrogen-implanted and rapid thermal annealed 6H-SiC

    Energy Technology Data Exchange (ETDEWEB)

    Abe, K. E-mail: abe@elcom.nitech.ac.jp; Eryu, O.; Kogi, O.; Nakashima, K

    2003-05-01

    The annealing time dependence of surface morphologies, crystallinity, and electrical characteristics for the high-dose nitrogen-implanted 6H-SiC has been investigated. Rapid thermal annealing (RTA) was performed at the temperature ranging from 1600 to 1850 deg. C for 20 s. In comparison with conventional furnace annealed (FA) samples (1550-1650 deg. C, 180 s in argon), the RTA samples had smoother surfaces and better crystallinity. While no reduction in the thickness of the implanted layer and no redistribution of implanted nitrogen atoms were observed in the RTA samples, the thickness of the implanted layer was reduced by FA. The sheet resistance and electron concentration of the RTA sample at 1750 deg. C were comparable to those of the FA sample at 1550 deg. C. We will discuss the difference between the RTA and the FA samples.

  4. Radon Levels Measured at a Touristic Thermal Spa Resort in Montagu (South Africa) and Associated Effective Doses.

    Science.gov (United States)

    Botha, R; Newman, R T; Maleka, P P

    2016-09-01

    Radon activity concentrations (in water and in air) were measured at 13 selected locations at the Avalon Springs thermal spa resort in Montagu (Western Cape, South Africa) to estimate the associated effective dose received by employees and visitors. A RAD-7 detector (DURRIDGE), based on alpha spectrometry, and electret detectors (E-PERM®Radelec) were used for these radon measurements. The primary source of radon was natural thermal waters from the hot spring, which were pumped to various locations on the resort, and consequently a range of radon in-water analyses were performed. Radon in-water activity concentration as a function of time (short term and long term measurements) and spatial distributions (different bathing pools, etc.) were studied. The mean radon in-water activity concentrations were found to be 205 ± 6 Bq L (source), 112 ± 5 Bq L (outdoor pool) and 79 ± 4 Bq L (indoor pool). Radon in-air activity concentrations were found to range between 33 ± 4 Bq m (at the outside bar) to 523 ± 26 Bq m (building enclosing the hot spring's source). The most significant potential radiation exposure identified is that due to inhalation of air rich in radon and its progeny by the resort employees. The annual occupational effective dose due to the inhalation of radon progeny ranges from 0.16 ± 0.01 mSv to 0.40 ± 0.02 mSv. For the water samples collected, the Ra in-water activity concentrations from samples collected were below the lower detection limit (~0.7 Bq L) of the γ-ray detector system used. No significant radiological health risk can be associated with radon and progeny from the hot spring at the Avalon Springs resort.

  5. Thermal transfer and apparent-dose distributions in poorly bleached mortar samples: Results from single grains and small aliquots of quartz

    DEFF Research Database (Denmark)

    Jain, M.; Thomsen, Kristina Jørkov; Bøtter-Jensen, L.

    2004-01-01

    and inner wall plaster from a building built in 1964. These samples are found to be both poorly bleached and weakly sensitive (only 0.3% of grains giving a detectable dose response). We study thermal transfer in single grains of quartz, investigate the grain-size dependence of bleaching in the size range 90...

  6. Changes in the thermal properties of PADC film-based nuclear track detectors produced by high doses of γ-radiation

    Energy Technology Data Exchange (ETDEWEB)

    Saad, A.F., E-mail: abdallahsaad56@hotmail.com [Physics Department, Faculty of Science, Zagazig University, 44519 Zagazig (Egypt); Physics Department, Faculty of Science, University of Benghazi, 9480 Benghazi (Libya); Saad, Noura; Abdalla, Y.K. [Physics Department, Faculty of Science, University of Benghazi, 9480 Benghazi (Libya)

    2014-04-01

    Highlights: • Thermal properties of PADC polymer-based NTDs have been investigated. • PADC films based NTDs were exposed to high doses of γ-rays. • The activation energy for thermal decomposition of PADC films was determined. • PADC films may be of use for industrial applications due to its response of γ-rays. • PADC film is a good technique for dose reading. - Abstract: Irradiation effects on the thermal properties of poly allyl diglycol carbonate (PADC) polymer-based nuclear track detectors (in the form of CR-39) have been investigated. PADC films were exposed to γ-rays at high doses ranging from 5.0 × 10{sup 5} to 1.0 × 10{sup 6} Gy. The induced modifications were analyzed by means of thermogravimetric analysis, which indicated that the PADC film decomposed in three main stages. The activation energy for thermal decomposition was determined using a type of Arrhenius equation based on the TGA experimental results. This study presents quantitative results showing that the exposed PADC films do not undergo continual further degradation from high-energy γ-photons with increase in dose. The experimental results also provide insight into the specific property changes induced by γ-rays, which may be of use for industrial applications.

  7. Evaluation of neutron dose and gamma dose at thermal facility of Peruvian research reactor RP-10; Evaluacion de la dosis gamma y de neutrones en la facilidad termica del reactor peruano de investigacion RP-10

    Energy Technology Data Exchange (ETDEWEB)

    Gomez, Javier; Miranda, Hector; Aparicio, Claudia; Lazaro, Gerardo [Instituto Peruano de Energia Nuclear (IPEN), Lima (Peru). Dept. de Calculo, Analisis y Seguridad (CASE)]. E-mail: hmcmiranda@hotmail.com; jjgb76@yahoo.com; caparicio@scientist.com; glazaro@ipen.gob.pe; Zuniga, Agustin [Instituto Peruano de Energia Nuclear (IPEN), Lima (Peru). Direccion General de Instalaciones (DGI)]. E-mail: azuniga@ipen.gob.pe

    2005-07-01

    One of main lines of work in the Peruvian nuclear reactor RP-10, is a complex systems simulation by mean of Monte Carlo technique, oriented in particular to characterization of irradiation facilities. In this work it is presented the comparison of experimental measurements, based in measure of thermal, epithermal and fast neutron flux distribution, neutron dose and gamma dose at thermal facility of RP-10, with the MCNP4B compute code, being observed a good agreement between both results. The neutron flux measures were carried out by irradiation of gold, indium and nickel metallic monitors; then it were measured the activities using a gamma spectrometry chain based on a hyperpure germanium (HPGe) detector. With these results the neutron dose was determined, and it was also measured, using a equipment based on a boron trifluoride detector (BF3, NRC-RemRad). A device based on Geiger Mueller detector (FAG-FH40FE) was used for the gamma dose rate measurement. Finally there were measured both gamma and neutron dose rate using TLD-600 and TLD-700 thermoluminescent dosimeters, which were previously characterized. (author)

  8. Electro-cumulation CNF project

    CERN Document Server

    Grishin, V G

    2000-01-01

    bound or free ion current within solid substances; non-plain symmetry; cumulation of the ion interaction. Experimental result: an Ice SuperPolarization. Cold nuclear fusion ? At http://www.shortway.to/to2084 . Keywords: ion, current, solid, symmetry, cumulation, cold nuclear fusion, polarization, depolarization, ionic conductor, superionic conductor, ice, crystal, strain, V-center, V-centre, doped crystal, interstitial impurity, intrinsic color center, high pressure technology, Bridgman, experiment, crowdion, dielectric, proton, layer, defect, lattice, dynamics, electromigration, mobility, muon catalysis, concentration, doping, dopant, conductivity, pycnonuclear reaction, permittivity, dielectric constant, point defects, interstitials, polarizability, imperfection, defect centers, glass, epitaxy, sodium hydroxide, metallic substrate, crystallization, point, tip, susceptibility, ferroelectric, ordering, force, correlation, collective, shift, distortion, coalescence, crowdions, electrolysis.

  9. Dose-Dependent Pattern of Inducible mRNA Expression of PIG3 Gene in Normal Human Lymphoblastoid Cells by Thermal Neutron

    Institute of Scientific and Technical Information of China (English)

    MA; Nan-ru; SUI; Li; WANG; Xiao; KONG; Fu-quan; LIU; Xiao-dan; ZHOU; Ping-kun

    2012-01-01

    <正>Using the thermal neutron produced by the hospital neutron irradiator, AHH-1 cell was irradiated at the various dose, 0, 0.5, 2, 4, 6 and 8 Gy, respectively. After irradiation, cells were collected at 2, 6, 12, 24 and 48 h post-irradiation, and then cell cycle distribution was tested using flow cytometry, as well as PIG3 mRNA expression level was detected using real-time fluorescent quantitative PCR detection.

  10. Cumulative Paired φ-Entropy

    Directory of Open Access Journals (Sweden)

    Ingo Klein

    2016-07-01

    Full Text Available A new kind of entropy will be introduced which generalizes both the differential entropy and the cumulative (residual entropy. The generalization is twofold. First, we simultaneously define the entropy for cumulative distribution functions (cdfs and survivor functions (sfs, instead of defining it separately for densities, cdfs, or sfs. Secondly, we consider a general “entropy generating function” φ, the same way Burbea et al. (IEEE Trans. Inf. Theory 1982, 28, 489–495 and Liese et al. (Convex Statistical Distances; Teubner-Verlag, 1987 did in the context of φ-divergences. Combining the ideas of φ-entropy and cumulative entropy leads to the new “cumulative paired φ-entropy” ( C P E φ . This new entropy has already been discussed in at least four scientific disciplines, be it with certain modifications or simplifications. In the fuzzy set theory, for example, cumulative paired φ-entropies were defined for membership functions, whereas in uncertainty and reliability theories some variations of C P E φ were recently considered as measures of information. With a single exception, the discussions in the scientific disciplines appear to be held independently of each other. We consider C P E φ for continuous cdfs and show that C P E φ is rather a measure of dispersion than a measure of information. In the first place, this will be demonstrated by deriving an upper bound which is determined by the standard deviation and by solving the maximum entropy problem under the restriction of a fixed variance. Next, this paper specifically shows that C P E φ satisfies the axioms of a dispersion measure. The corresponding dispersion functional can easily be estimated by an L-estimator, containing all its known asymptotic properties. C P E φ is the basis for several related concepts like mutual φ-information, φ-correlation, and φ-regression, which generalize Gini correlation and Gini regression. In addition, linear rank tests for scale that

  11. Measurements of thermal- and slow-neutron dose distributions in ordinary concrete shield using a reactor neutron beam of different energy ranges

    Energy Technology Data Exchange (ETDEWEB)

    Megahid, R.M.; Makarious, A.S.; El-Kolaly, M.A.; Afifi, Y.A.

    1980-01-01

    Experimental studies on the distribution and attenuation of thermal and slow neutron doses in ordinary concrete shield have been carried-out. A collimated beam of reactor neutrons emitted from one of the horizontal channels of the ET-RR-1 reactor was used. Measurements were performed using, a direct beam, cadmium filtered beam and boron carbide filtered beam. The neutron doses were measured using thermolumin-escent Li/sub 2/B/sub 4/O/sub 7/ detectors. The measured data have been analyzed and a group of attenuation curves were given for beams of reactor neutrons of different energy. These curves show that cadmium and boron carbide filters tend to decrease the neutron doses specially at the beginning of penetration. The data were transformed to that which would be obtained using neutron sources of different geometries.

  12. The Algebra of the Cumulative Percent Operation.

    Science.gov (United States)

    Berry, Andrew J.

    2002-01-01

    Discusses how to help students avoid some pervasive reasoning errors in solving cumulative percent problems. Discusses the meaning of ."%+b%." the additive inverse of ."%." and other useful applications. Emphasizes the operational aspect of the cumulative percent concept. (KHR)

  13. Adaptive strategies for cumulative cultural learning.

    Science.gov (United States)

    Ehn, Micael; Laland, Kevin

    2012-05-21

    The demographic and ecological success of our species is frequently attributed to our capacity for cumulative culture. However, it is not yet known how humans combine social and asocial learning to generate effective strategies for learning in a cumulative cultural context. Here we explore how cumulative culture influences the relative merits of various pure and conditional learning strategies, including pure asocial and social learning, critical social learning, conditional social learning and individual refiner strategies. We replicate the Rogers' paradox in the cumulative setting. However, our analysis suggests that strategies that resolved Rogers' paradox in a non-cumulative setting may not necessarily evolve in a cumulative setting, thus different strategies will optimize cumulative and non-cumulative cultural learning.

  14. "Buddha's Light" of Cumulative Particles

    CERN Document Server

    Kopeliovich, Vladimir B; Potashnikova, Irina K

    2014-01-01

    We show analytically that in the cumulative particles production off nuclei multiple interactions lead to a glory-like backward focusing effect. Employing the small phase space method we arrived at a characteristic angular dependence of the production cross section $d\\sigma \\sim 1/ \\sqrt {\\pi - \\theta}$ near the strictly backward direction. This effect takes place for any number $n\\geq 3 $ of interactions of rescattered particle, either elastic or inelastic (with resonance excitations in intermediate states), when the final particle is produced near corresponding kinematical boundary. Such a behaviour of the cross section near the backward direction is in qualitative agreement with some of available data.

  15. A Resource Cost Aware Cumulative

    Science.gov (United States)

    Simonis, Helmut; Hadzic, Tarik

    We motivate and introduce an extension of the well-known cumulative constraint which deals with time and volume dependent cost of resources. Our research is primarily interested in scheduling problems under time and volume variable electricity costs, but the constraint equally applies to manpower scheduling when hourly rates differ over time and/or extra personnel incur higher hourly rates. We present a number of possible lower bounds on the cost, including a min-cost flow, different LP and MIP models, as well as greedy algorithms, and provide a theoretical and experimental comparison of the different methods.

  16. 职业性噪声聋的发生、发展规律及与累积噪声暴露剂量的关系研究%The occurrence and development of occupational noise deafness and its relationship with the cumulative noise exposure dose

    Institute of Scientific and Technical Information of China (English)

    王雪琴

    2015-01-01

    Objective: To analyze and investigate the occurrence and development of occupational noise deafness and its re-lationship with the cumulative noise exposure dose (CNE).Methods:Randomly selecting a city and medium-sized enterprises 120 workers and management are as the research object, to the enterprise operating environment noise monitoring, investigation object were measured by pure tone threshold audiometry, calculating the cumulative noise exposure, to investigate the occurrence and occupational noise induced hearing loss.Results: The noise pressure level of the examination site was higher than that in other places; when the CNE increases, high-frequency loss, language frequency loss detection rate had significant difference; oc-cupational noise induced deafness related to rate and development and CNE, to 100 dB (a) years as threshold.Conclusion:The cumulative noise exposure dose and occupational noise induced deafness, the law of development there is a certain relationship, early detection threshold anomaly or high frequency audibility threshold change of patients,, improve efficiency and patient quality of life.%目的:分析和探讨职业性噪声聋的发生、发展规律及与累积噪声暴露剂量(CNE)的关系。方法随机选取某城市中型企业中120名工人及管理者作为研究对象,对企业作业环境噪音进行监测,组织调查对象进行纯音听阈测定,计算累积噪声暴露剂量,探讨与职业性噪声聋的发生、发展规律的关系。结果检查现场噪声声压级均高于其他场所;当CNE升高时,高频损失、语频损失检出率差异明显;职业性噪声聋发生率及发展与CNE有关,以100dB(A)年为阈值。结论累积噪声暴露剂量与职业性噪声聋的发生、发展规律存在一定的关系,早期发现听阈异常或高频听阈改变的患者,及时控制职业噪音暴露量,并按规定调离噪声作业岗位,避免病情进一步发展,提高患者工作效率和生活质量。

  17. A paradox of cumulative culture.

    Science.gov (United States)

    Kobayashi, Yutaka; Wakano, Joe Yuichiro; Ohtsuki, Hisashi

    2015-08-21

    Culture can grow cumulatively if socially learnt behaviors are improved by individual learning before being passed on to the next generation. Previous authors showed that this kind of learning strategy is unlikely to be evolutionarily stable in the presence of a trade-off between learning and reproduction. This is because culture is a public good that is freely exploited by any member of the population in their model (cultural social dilemma). In this paper, we investigate the effect of vertical transmission (transmission from parents to offspring), which decreases the publicness of culture, on the evolution of cumulative culture in both infinite and finite population models. In the infinite population model, we confirm that culture accumulates largely as long as transmission is purely vertical. It turns out, however, that introduction of even slight oblique transmission drastically reduces the equilibrium level of culture. Even more surprisingly, if the population size is finite, culture hardly accumulates even under purely vertical transmission. This occurs because stochastic extinction due to random genetic drift prevents a learning strategy from accumulating enough culture. Overall, our theoretical results suggest that introducing vertical transmission alone does not really help solve the cultural social dilemma problem. Copyright © 2015 Elsevier Ltd. All rights reserved.

  18. Thermally assisted OSL application for equivalent dose estimation; comparison of multiple equivalent dose values as well as saturation levels determined by luminescence and ESR techniques for a sedimentary sample collected from a fault gouge

    Science.gov (United States)

    Şahiner, Eren; Meriç, Niyazi; Polymeris, George S.

    2017-02-01

    Equivalent dose estimation (De) constitutes the most important part of either trap-charge dating techniques or dosimetry applications. In the present work, multiple, independent equivalent dose estimation approaches were adopted, using both luminescence and ESR techniques; two different minerals were studied, namely quartz as well as feldspathic polymineral samples. The work is divided into three independent parts, depending on the type of signal employed. Firstly, different De estimation approaches were carried out on both polymineral and contaminated quartz, using single aliquot regenerative dose protocols employing conventional OSL and IRSL signals, acquired at different temperatures. Secondly, ESR equivalent dose estimations using the additive dose procedure both at room temperature and at 90 K were discussed. Lastly, for the first time in the literature, a single aliquot regenerative protocol employing a thermally assisted OSL signal originating from Very Deep Traps was applied for natural minerals. Rejection criteria such as recycling and recovery ratios are also presented. The SAR protocol, whenever applied, provided with compatible De estimations with great accuracy, independent on either the type of mineral or the stimulation temperature. Low temperature ESR signals resulting from Al and Ti centers indicate very large De values due to bleaching in-ability, associated with large uncertainty values. Additionally, dose saturation of different approaches was investigated. For the signal arising from Very Deep Traps in quartz saturation is extended almost by one order of magnitude. It is interesting that most of De values yielded using different luminescence signals agree with each other and ESR Ge center has very large D0 values. The results presented above highly support the argument that the stability and the initial ESR signal of the Ge center is highly sample-dependent, without any instability problems for the cases of quartz resulting from fault gouge.

  19. Thermally assisted OSL application for equivalent dose estimation; comparison of multiple equivalent dose values as well as saturation levels determined by luminescence and ESR techniques for a sedimentary sample collected from a fault gouge

    Energy Technology Data Exchange (ETDEWEB)

    Şahiner, Eren, E-mail: sahiner@ankara.edu.tr; Meriç, Niyazi, E-mail: meric@ankara.edu.tr; Polymeris, George S., E-mail: gspolymeris@ankara.edu.tr

    2017-02-01

    Highlights: • Multiple equivalent dose estimations were carried out. • Additive ESR and regenerative luminescence were applied. • Preliminary SAR results employing TA-OSL signal were discussed. • Saturation levels of ESR and luminescence were investigated. • IRSL{sub 175} and SAR TA-OSL stand as very promising for large doses. - Abstract: Equivalent dose estimation (D{sub e}) constitutes the most important part of either trap-charge dating techniques or dosimetry applications. In the present work, multiple, independent equivalent dose estimation approaches were adopted, using both luminescence and ESR techniques; two different minerals were studied, namely quartz as well as feldspathic polymineral samples. The work is divided into three independent parts, depending on the type of signal employed. Firstly, different D{sub e} estimation approaches were carried out on both polymineral and contaminated quartz, using single aliquot regenerative dose protocols employing conventional OSL and IRSL signals, acquired at different temperatures. Secondly, ESR equivalent dose estimations using the additive dose procedure both at room temperature and at 90 K were discussed. Lastly, for the first time in the literature, a single aliquot regenerative protocol employing a thermally assisted OSL signal originating from Very Deep Traps was applied for natural minerals. Rejection criteria such as recycling and recovery ratios are also presented. The SAR protocol, whenever applied, provided with compatible D{sub e} estimations with great accuracy, independent on either the type of mineral or the stimulation temperature. Low temperature ESR signals resulting from Al and Ti centers indicate very large D{sub e} values due to bleaching in-ability, associated with large uncertainty values. Additionally, dose saturation of different approaches was investigated. For the signal arising from Very Deep Traps in quartz saturation is extended almost by one order of magnitude. It is

  20. Activation of JNK pathway in spinal astrocytes contributes to acute ultra-low-dose morphine thermal hyperalgesia.

    Science.gov (United States)

    Sanna, Maria Domenica; Ghelardini, Carla; Galeotti, Nicoletta

    2015-07-01

    Accumulating evidence suggests that opioid analgesics can lead to paradoxical sensitization to pain when delivered in different administration patterns. Although opioid tolerance-induced hyperalgesia is largely studied, little is known about the mechanisms underlying acute ultra-low-dose morphine hyperalgesia. Activation of spinal glial cells is reported to regulate pain hypersensitivity. To elucidate the mechanism involved in acute ultra-low-dose morphine hyperalgesia, we tested whether an opioid agonist promoted the activation of spinal astrocytes and microglia and investigated the cellular pathways involved. Ultra-low-dose morphine activated spinal astrocytes with no effect on microglia. The astrocyte activation was selectively prevented by the opioid antagonist naloxone, the μ-opioid receptor (MOR) silencing and the JNK inhibitor SP600125. Morphine elevated spinal JNK1, JNK2, and c-Jun phosphorylation. Conversely, phosphorylation of cAMP response element-binding protein (CREB) and signal transducer and activator of transcription-1 (STAT-1) was not elevated, and nuclear factor kappa B (NF-κB) levels remained unmodified. Administration of SP600125 and the N-methyl-D-aspartate (NMDA) antagonist MK801 prevented morphine hyperalgesia. Ultra-low-dose morphine increased protein kinase C (PKC) γ phosphorylation. Pretreatment with a PKC inhibitor prevented morphine hyperalgesia and JNK and c-Jun overphosphorylation, indicating PKC is a JNK upstream modulator and illustrating the presence of a pathway involving PKC, NMDA, and JNK activated by morphine. Immunofluorescence experiments indicated the neuronal localization of spinal MOR. However, JNK was not detected in MOR-expressing cells, showing the presence of a neuron-astrocyte signaling pathway. These results illustrate the selective activation of an astrocyte JNK pathway after the stimulation of neuronal MOR, which contributes to ultra-low-dose morphine hyperalgesia.

  1. Dietary lecithin potentiates thermal tolerance and cellular stress protection of milk fish (Chanos Chanos) reared under low dose endosulfan-induced stress.

    Science.gov (United States)

    Kumar, Neeraj; Minhas, P S; Ambasankar, K; Krishnani, K K; Rana, R S

    2014-12-01

    Endosulfan is an organochlorine pesticide commonly found in aquatic environments that has been found to reduce thermal tolerance of fish. Lipotropes such as the food additive, Lecithin has been shown to improve thermal tolerance in fish species. This study was conducted to evaluate the role of lipotropes (lecithin) for enhancing the thermal tolerance of Chanos chanos reared under sublethal low dose endosulfan-induced stress. Two hundred and twenty-five fish were distributed randomly into five treatments, each with three replicates. Four isocaloric and isonitrogenous diets were prepared with graded levels of lecithin: normal water and fed with control diet (En0/L0), endosulfan-treated water and fed with control diet (En/L0), endosulfan-treated water and fed with 1% (En/L1%), 1.5% (En/L 1.5%) and 2% (En/L 2%) lecithin supplemented feed. The endosulfan in treated water was maintained at the level of 1/40th of LC50 (0.52ppb). At the end of the five weeks, critical temperature maxima (CTmax), lethal temperature maxima (LTmax), critical temperature minima (CTmin) and lethal temperature minima (LTmin) were Determined. There was a significant (Plecithin on temperature tolerance (CTmax, LTmax, CTmin and LTmin) of the groups fed with 1, 1.5 and 2% lecithin-supplemented diet compared to control and endosulfan-exposed groups. Positive correlations were observed between CT max and LTmax (R(2)=0.934) as well as between CTmin and LTmin (R(2)=0.9313). At the end of the thermal tolerance study, endosulfan-induced changes in cellular stress enzymes (Catalase, SOD and GST in liver and gill and neurotansmitter enzyme, brain AChE) were significantly (plecithin. We herein report the role of lecithin in enhancing the thermal tolerance and protection against cellular stress in fish exposed to an organochlorine pesticide. Copyright © 2014 Elsevier Ltd. All rights reserved.

  2. Cumulants of heat transfer across nonlinear quantum systems

    Science.gov (United States)

    Li, Huanan; Agarwalla, Bijay Kumar; Li, Baowen; Wang, Jian-Sheng

    2013-12-01

    We consider thermal conduction across a general nonlinear phononic junction. Based on two-time observation protocol and the nonequilibrium Green's function method, heat transfer in steady-state regimes is studied, and practical formulas for the calculation of the cumulant generating function are obtained. As an application, the general formalism is used to study anharmonic effects on fluctuation of steady-state heat transfer across a single-site junction with a quartic nonlinear on-site pinning potential. An explicit nonlinear modification to the cumulant generating function exact up to the first order is given, in which the Gallavotti-Cohen fluctuation symmetry is found still valid. Numerically a self-consistent procedure is introduced, which works well for strong nonlinearity.

  3. Cumulative human impacts on marine predators

    DEFF Research Database (Denmark)

    Maxwell, Sara M; Hazen, Elliott L; Bograd, Steven J

    2013-01-01

    Stressors associated with human activities interact in complex ways to affect marine ecosystems, yet we lack spatially explicit assessments of cumulative impacts on ecologically and economically key components such as marine predators. Here we develop a metric of cumulative utilization and impact...

  4. A new method of measuring a large pulsed neutron fluence or dose exploiting the die-away of thermalized neutrons in a polyethylene moderator

    Science.gov (United States)

    Leake, J. W.; Lowe, T.; Mason, R. S.; White, G.

    2010-01-01

    Computer simulations of the response to very short pulses of neutron and gamma radiation of a spherical polyethylene moderator with a central thermal neutron counter and a new, fast, active restore amplifier system have been carried out. A large neutron burst produces count rates in the detector that are too high to measure initially but when the exponential decay of the count rate falls below about 50 k per sec then counting can start. If the counts are recorded in contiguous time intervals (of 60 μs in this case) and the time is measured at which the measured count in an interval falls to 1 or 2 then the size of the initial burst can be calculated. It is shown that it should be possible to measure pulsed neutron ambient dose equivalent H*(10) or dose equivalent rate from about 2 nSv up to about 100 μSv per burst, or 7.2 N μSv s h -1 to 360 N mSv s h -1, where N is the number of neutron bursts per second. The calculations show that a gamma burst of about 10 μGy can be tolerated without affecting the measurement of the largest neutron bursts. This extends our earlier estimate of the maximum dose that can be measured for pulsed neutrons by more than 10 k. This method could also be used to measure the neutron fluence or dose from a single unplanned event such as a beam dump on an accelerator or a criticality incident from fissile material. Although the method described is new it is based on a combination of proven techniques.

  5. Effects of target-controlled infusion of high-dose naloxone on pain and hyperalgesia in a human thermal injury model: a study protocol

    Science.gov (United States)

    Springborg, Anders D.; Jensen, Elisabeth K.; Taylor, Bradley K.; Werner, Mads U.

    2016-01-01

    Abstract Mu-opioid-receptor antagonists have been extensively studied in experimental research as pharmacological tools uncovering mechanisms of pain modulation by the endogenous opioid system. In rodents, administration of high doses of mu-opioid-receptor antagonists after the resolution of an inflammatory injury has demonstrated reinstatement of nociceptive hypersensitivity indicating unmasking of latent sensitization. In a recent human study, pain hypersensitivity assessed as secondary hyperalgesia area (SHA), was reinstated 7 days after a mild thermal injury, in 4 out of 12 subjects after a naloxone infusion. The aims of the present study are first, to replicate our previous findings in a larger-sized study; second, to examine if high sensitizers (subjects presenting with large SHA after a thermal injury) develop a higher degree of hypersensitivity after naloxone challenge than low sensitizers (subjects presenting with restricted SHA after a thermal injury); and third to examine a dose–response relationship between 3 stable naloxone concentrations controlled by target-controlled infusion, and the unmasking of latent sensitization. Healthy participants (n = 80) underwent a screening day (day 0) with induction of a thermal skin injury (47°C, 420 seconds, 12.5 cm2). Assessment of SHA was performed 1 and 2 hours after the injury. Using an enriched design, only participants belonging to the upper quartile of SHA (Q4, high sensitizers; n = 20) and the lower quartile of SHA (Q1, low sensitizers; n = 20) continued the study, comprising 4 consecutive days—days 1 to 4. Thermal skin injuries were repeated on day 1 and day 3, whereas day 2 and day 4 (7 days after day 1 and day 3, respectively) were target-controlled infusion days in which the subjects were randomly allocated to receive either naloxone (3.25 mg/kg, 4 mg/mL) or placebo (normal saline) intravenous. The primary outcome was SHA assessed by weighted-pin instrument (128 mN) 0, 1, 2

  6. Nonlinear cumulative damage model for multiaxial fatigue

    Institute of Scientific and Technical Information of China (English)

    SHANG De-guang; SUN Guo-qin; DENG Jing; YAN Chu-liang

    2006-01-01

    On the basis of the continuum fatigue damage theory,a nonlinear uniaxial fatigue cumulative damage model is first proposed.In order to describe multiaxial fatigue damage characteristics,a nonlinear multiaxial fatigue cumulative damage model is developed based on the critical plane approach,The proposed model can consider the multiaxial fatigue limit,mean hydrostatic pressure and the unseparated characteristic for the damage variables and loading parameters.The recurrence formula of fatigue damage model was derived under multilevel loading,which is used to predict multiaxial fatigue life.The results showed that the proposed nonlinear multiaxial fatigue cumulative damage model is better than Miner's rule.

  7. Cumulative risk: toxicity and interactions of physical and chemical stressors.

    Science.gov (United States)

    Rider, Cynthia V; Boekelheide, Kim; Catlin, Natasha; Gordon, Christopher J; Morata, Thais; Selgrade, Maryjane K; Sexton, Kenneth; Simmons, Jane Ellen

    2014-01-01

    Recent efforts to update cumulative risk assessment procedures to incorporate nonchemical stressors ranging from physical to psychosocial reflect increased interest in consideration of the totality of variables affecting human health and the growing desire to develop community-based risk assessment methods. A key roadblock is the uncertainty as to how nonchemical stressors behave in relationship to chemical stressors. Physical stressors offer a reasonable starting place for measuring the effects of nonchemical stressors and their modulation of chemical effects (and vice versa), as they clearly differ from chemical stressors; and "doses" of many physical stressors are more easily quantifiable than those of psychosocial stressors. There is a commonly held belief that virtually nothing is known about the impact of nonchemical stressors on chemically mediated toxicity or the joint impact of coexposure to chemical and nonchemical stressors. Although this is generally true, there are several instances where a substantial body of evidence exists. A workshop titled "Cumulative Risk: Toxicity and Interactions of Physical and Chemical Stressors" held at the 2013 Society of Toxicology Annual Meeting provided a forum for discussion of research addressing the toxicity of physical stressors and what is known about their interactions with chemical stressors, both in terms of exposure and effects. Physical stressors including sunlight, heat, radiation, infectious disease, and noise were discussed in reference to identifying pathways of interaction with chemical stressors, data gaps, and suggestions for future incorporation into cumulative risk assessments.

  8. Cumulant expansion and analytic continuation in Monte Carlo simulation of classical Lennard-Jones clusters.

    Science.gov (United States)

    Kunikeev, Sharif D; Kim, Kwang S

    2012-11-01

    The Monte Carlo (MC) estimates of thermal averages are usually functions of system control parameters λ, such as temperature, volume, and interaction couplings. Given the MC average at a set of prescribed control parameters λ{0}, the problem of analytic continuation of the MC data to λ values in the neighborhood of λ{0} is considered in both classic and quantum domains. The key result is the theorem that links the differential properties of thermal averages to the higher order cumulants. The theorem and analytic continuation formulas expressed via higher order cumulants are numerically tested on the classical Lennard-Jones cluster system of N=13, 55, and 147 neon particles.

  9. Cumulative cultural learning: Development and diversity.

    Science.gov (United States)

    Legare, Cristine H

    2017-07-24

    The complexity and variability of human culture is unmatched by any other species. Humans live in culturally constructed niches filled with artifacts, skills, beliefs, and practices that have been inherited, accumulated, and modified over generations. A causal account of the complexity of human culture must explain its distinguishing characteristics: It is cumulative and highly variable within and across populations. I propose that the psychological adaptations supporting cumulative cultural transmission are universal but are sufficiently flexible to support the acquisition of highly variable behavioral repertoires. This paper describes variation in the transmission practices (teaching) and acquisition strategies (imitation) that support cumulative cultural learning in childhood. Examining flexibility and variation in caregiver socialization and children's learning extends our understanding of evolution in living systems by providing insight into the psychological foundations of cumulative cultural transmission-the cornerstone of human cultural diversity.

  10. In-situ Thermal Annealing of On-Membrane SOI Semiconductor-Based Devices After High Gamma Dose Irradiation.

    Science.gov (United States)

    Amor, Sedki; André, Nicolas; Kilchytska, Valeriya; Tounsi, Fares; Mezghani, Brahim; Gérard, Pierre; Ali, S Z; Udrea, Florin; Flandre, Denis; Francis, Laurent A

    2017-03-14

    In this paper, we investigate the recovery of some semiconductor-based components, such as N/P-type field-effect transistors (FETs) and a Complementary Metal-Oxide-Semiconductor (CMOS) inverter, after being exposed to a high total dose of gamma rays radiation. The employed method consists mainly in a rapid, low power and in-situ annealing mitigation technique by Silicon-On-Insulator (SOI) micro-hotplates. Due to the ionizing effect of the gamma irradiation, the threshold voltages showed an average shift of 580 mV for N-channel transistors, and -360 mV for P-MOSFETs. A 4 min double-cycles annealing of components with a temperature of the heater up to 465°C, corresponding to a maximum power of 38 mW, ensured a partial recovery but was not sufficient for a full recovery. The degradation has been completely recovered after the use of a built-in high temperature annealing process, up to 975 °C for 8 min corresponding to a maximum power of 112 mW, which restored the normal operating characteristics for all devices after their irradiation.

  11. Calculating Cumulative Binomial-Distribution Probabilities

    Science.gov (United States)

    Scheuer, Ernest M.; Bowerman, Paul N.

    1989-01-01

    Cumulative-binomial computer program, CUMBIN, one of set of three programs, calculates cumulative binomial probability distributions for arbitrary inputs. CUMBIN, NEWTONP (NPO-17556), and CROSSER (NPO-17557), used independently of one another. Reliabilities and availabilities of k-out-of-n systems analyzed. Used by statisticians and users of statistical procedures, test planners, designers, and numerical analysts. Used for calculations of reliability and availability. Program written in C.

  12. Cumulative cultural evolution: the role of teaching.

    Science.gov (United States)

    Castro, Laureano; Toro, Miguel A

    2014-04-21

    In humans, cultural transmission occurs usually by cumulative inheritance, generating complex adaptive behavioral features. Cumulative culture requires key psychological processes (fundamentally imitation and teaching) that are absent or impoverished in non-human primates. In this paper we analyze the role that teaching has played in human cumulative cultural evolution. We assume that a system of cumulative culture generates increasingly adaptive behaviors, that are also more complex and difficult to imitate. Our thesis is that, as cultural traits become more complex, cumulative cultural transmission requires teaching to ensure accurate transmission from one generation to the next. In an increasingly complex cultural environment, we consider that individuals commit errors in imitation. We develop a model of cumulative cultural evolution in a changing environment and show that these errors hamper the process of cultural accumulation. We also show that a system of teaching between parents and offspring that increases the fidelity of imitation unblocks the accumulation and becomes adaptive whenever the gain in fitness compensates the cost of teaching.

  13. Human cumulative culture: a comparative perspective.

    Science.gov (United States)

    Dean, Lewis G; Vale, Gill L; Laland, Kevin N; Flynn, Emma; Kendal, Rachel L

    2014-05-01

    Many animals exhibit social learning and behavioural traditions, but human culture exhibits unparalleled complexity and diversity, and is unambiguously cumulative in character. These similarities and differences have spawned a debate over whether animal traditions and human culture are reliant on homologous or analogous psychological processes. Human cumulative culture combines high-fidelity transmission of cultural knowledge with beneficial modifications to generate a 'ratcheting' in technological complexity, leading to the development of traits far more complex than one individual could invent alone. Claims have been made for cumulative culture in several species of animals, including chimpanzees, orangutans and New Caledonian crows, but these remain contentious. Whilst initial work on the topic of cumulative culture was largely theoretical, employing mathematical methods developed by population biologists, in recent years researchers from a wide range of disciplines, including psychology, biology, economics, biological anthropology, linguistics and archaeology, have turned their attention to the experimental investigation of cumulative culture. We review this literature, highlighting advances made in understanding the underlying processes of cumulative culture and emphasising areas of agreement and disagreement amongst investigators in separate fields.

  14. Finite-volume cumulant expansion in QCD-colorless plasma

    Energy Technology Data Exchange (ETDEWEB)

    Ladrem, M. [Taibah University, Physics Department, Faculty of Science, Al-Madinah, Al-Munawwarah (Saudi Arabia); Physics Department, Algiers (Algeria); ENS-Vieux Kouba (Bachir El-Ibrahimi), Laboratoire de Physique et de Mathematiques Appliquees (LPMA), Algiers (Algeria); Ahmed, M.A.A. [Taibah University, Physics Department, Faculty of Science, Al-Madinah, Al-Munawwarah (Saudi Arabia); ENS-Vieux Kouba (Bachir El-Ibrahimi), Laboratoire de Physique et de Mathematiques Appliquees (LPMA), Algiers (Algeria); Taiz University in Turba, Physics Department, Taiz (Yemen); Alfull, Z.Z. [Taibah University, Physics Department, Faculty of Science, Al-Madinah, Al-Munawwarah (Saudi Arabia); Cherif, S. [ENS-Vieux Kouba (Bachir El-Ibrahimi), Laboratoire de Physique et de Mathematiques Appliquees (LPMA), Algiers (Algeria); Ghardaia University, Sciences and Technologies Department, Ghardaia (Algeria)

    2015-09-15

    Due to the finite-size effects, the localization of the phase transition in finite systems and the determination of its order, become an extremely difficult task, even in the simplest known cases. In order to identify and locate the finite-volume transition point T{sub 0}(V) of the QCD deconfinement phase transition to a colorless QGP, we have developed a new approach using the finite-size cumulant expansion of the order parameter and the L{sub mn}-method. The first six cumulants C{sub 1,2,3,4,5,6} with the corresponding under-normalized ratios (skewness Σ, kurtosis κ, pentosis Π{sub ±}, and hexosis H{sub 1,2,3}) and three unnormalized combinations of them, (O = σ{sup 2}κΣ{sup -1},U = σ{sup -2}Σ{sup -1},N = σ{sup 2}κ) are calculated and studied as functions of (T, V). A new approach, unifying in a clear and consistent way the definitions of cumulant ratios, is proposed.Anumerical FSS analysis of the obtained results has allowed us to locate accurately the finite-volume transition point. The extracted transition temperature value T{sub 0}(V) agrees with that expected T{sub 0}{sup N}(V) from the order parameter and the thermal susceptibility χ{sub T} (T, V), according to the standard procedure of localization to within about 2%. In addition to this, a very good correlation factor is obtained proving the validity of our cumulants method. The agreement of our results with those obtained by means of other models is remarkable. (orig.)

  15. Factors affecting the infectivity of tissues from pigs with classical swine fever: thermal inactivation rates and oral infectious dose.

    Science.gov (United States)

    Cowan, Lucie; Haines, Felicity J; Everett, Helen E; Crudgington, Bentley; Johns, Helen L; Clifford, Derek; Drew, Trevor W; Crooke, Helen R

    2015-03-23

    Outbreaks of classical swine fever are often associated with ingestion of pig meat or products derived from infected pigs. Assessment of the disease risks associated with material of porcine origin requires knowledge on the likely amount of virus in the original material, how long the virus may remain viable within the resulting product and how much of that product would need to be ingested to result in infection. Using material from pigs infected with CSFV, we determined the viable virus concentrations in tissues that comprise the majority of pork products. Decimal reduction values (D values), the time required to reduce the viable virus load by 90% (or 1 log10), were determined at temperatures of relevance for chilling, cooking, composting and ambient storage. The rate of CSFV inactivation varied in different tissues. At lower temperatures, virus remained viable for substantially longer in muscle and serum compared to lymphoid and fat tissues. To enable estimation of the temperature dependence of inactivation, the temperature change required to change the D values by 90% (Z values) were determined as 13 °C, 14 °C, 12 °C and 10 °C for lymph node, fat, muscle and serum, respectively. The amount of virus required to infect 50% of pigs by ingestion was determined by feeding groups of animals with moderately and highly virulent CSFV. Interestingly, the virulent virus did not initiate infection at a lower dose than the moderately virulent strain. Although higher than for intranasal inoculation, the amount of virus required for infection via ingestion is present in only a few grams of tissue from infected animals.

  16. Clinical experience with daily doses of misonidazole

    Energy Technology Data Exchange (ETDEWEB)

    Kogelnik, H.D.; Reinartz, G.; Szepesi, T.; Seitz, W.; Wurst, F.; Mamoli, B.; Wessely, P.; Stark, H.

    1980-11-01

    In this pilot study daily low doses of misonidazole (in the range of 1 to 2 g) up to cumulative doses between 7 and 19 g/m/sup 2/ were used. Serum levels were analysed at different times after administration and according to several dose regimens. We related the cumulative doses to the incidence and severity of the observed peripheral neuropathies. The aim was to find an effective daily low-dose schedule of misonidazole with a clinically acceptable incidence of side effects. Some impressive clinical responses were observed.

  17. Predicting Cumulative Incidence Probability by Direct Binomial Regression

    DEFF Research Database (Denmark)

    Scheike, Thomas H.; Zhang, Mei-Jie

    Binomial modelling; cumulative incidence probability; cause-specific hazards; subdistribution hazard......Binomial modelling; cumulative incidence probability; cause-specific hazards; subdistribution hazard...

  18. Cumulative Culture and Future Thinking: Is Mental Time Travel a Prerequisite to Cumulative Cultural Evolution?

    Science.gov (United States)

    Vale, G. L.; Flynn, E. G.; Kendal, R. L.

    2012-01-01

    Cumulative culture denotes the, arguably, human capacity to build on the cultural behaviors of one's predecessors, allowing increases in cultural complexity to occur such that many of our cultural artifacts, products and technologies have progressed beyond what a single individual could invent alone. This process of cumulative cultural evolution…

  19. High cumulative insulin exposure : a risk factor of atherosclerosis in type 1 diabetes?

    NARCIS (Netherlands)

    Muis, MJ; Bots, ML; Bilo, HJG; Hoogma, RPLM; Hoekstra, JBL; Grobbee, DE; Stolk, RP

    Background: Since insulin therapy might have an atherogenic effect, we studied the relationship between cumulative insulin dose and atherosclerosis in type 1 diabetes. We have focused on patients with type 1 diabetes instead of type 2 diabetes to minimise the effect of insulin resistance as a

  20. Real-time monitoring of radiofrequency ablation of liver tumors using thermal-dose calculation by MR temperature imaging: initial results in nine patients, including follow-up

    Energy Technology Data Exchange (ETDEWEB)

    Lepetit-Coiffe, Matthieu; Quesson, Bruno; Moonen, Chrit T.W. [Universite Victor Segalen Bordeaux 2, Laboratoire Imagerie Moleculaire et Fonctionnelle: de la physiologie a la therapie CNRS UMR 5231, Bordeaux Cedex (France); Laumonier, Herve; Trillaud, Herve [Universite Victor Segalen Bordeaux 2, Laboratoire Imagerie Moleculaire et Fonctionnelle: de la physiologie a la therapie CNRS UMR 5231, Bordeaux Cedex (France); Service de Radiologie, Hopital Saint-Andre, CHU Bordeaux, Bordeaux (France); Seror, Olivier [Universite Victor Segalen Bordeaux 2, Laboratoire Imagerie Moleculaire et Fonctionnelle: de la physiologie a la therapie CNRS UMR 5231, Bordeaux Cedex (France); Service de Radiologie, Hopital Jean Verdier, Bondy (France); Sesay, Musa-Bahazid [Service d' Anesthesie Reanimation III, Hopital Pellegrin, CHU Bordeaux, Bordeaux (France); Grenier, Nicolas [Universite Victor Segalen Bordeaux 2, Laboratoire Imagerie Moleculaire et Fonctionnelle: de la physiologie a la therapie CNRS UMR 5231, Bordeaux Cedex (France); Service d' Imagerie Diagnostique et Therapeutique de l' Adulte, Hopital Pellegrin, CHU Bordeaux, Bordeaux (France)

    2010-01-15

    To assess the practical feasibility and effectiveness of real-time magnetic resonance (MR) temperature monitoring for the radiofrequency (RF) ablation of liver tumours in a clinical setting, nine patients (aged 49-87 years, five men and four women) with one malignant tumour (14-50 mm, eight hepatocellular carcinomas and one colorectal metastasis), were treated by 12-min RF ablation using a 1.5-T closed magnet for real-time temperature monitoring. The clinical monopolar RF device was filtered at 64 MHz to avoid electromagnetic interference. Real-time computation of thermal-dose (TD) maps, based on Sapareto and Dewey's equation, was studied to determine its ability to provide a clear end-point of the RF procedure. Absence of local recurrence on follow-up MR images obtained 45 days after the RF ablation was used to assess the apoptotic and necrotic prediction obtained by real-time TD maps. Seven out of nine tumours were completely ablated according to the real-time TD maps. Compared with 45-day follow-up MR images, TD maps accurately predicted two primary treatment failures, but were not relevant in the later progression of one case of secondary local tumour. The real-time TD concept is a feasible and promising monitoring method for the RF ablation of liver tumours. (orig.)

  1. Is cumulated pyrethroid exposure associated with prediabetes?

    DEFF Research Database (Denmark)

    Hansen, Martin Rune; Jørs, Erik; Lander, Flemming;

    2014-01-01

    , cumulative exposure) was assessed from questionnaire data. Participants were asked about symptoms of diabetes. Blood samples were analyzed for glycosylated hemoglobin (HbA1c), a measure of glucose regulation. No association was found between pyrethroid exposure and diabetes symptoms. The prevalence...

  2. Cumulative Disadvantage among the Highly Ambitious.

    Science.gov (United States)

    McClelland, Katherine

    1990-01-01

    Using a social reproduction theory framework, analyzes the process by which high school seniors aspiring to high-level positions are sorted out after graduation. Analyzes early educational attainments and changes in occupational expectations. Shows a process of cumulative disadvantage in which White males are more likely to achieve their goals.…

  3. Pavlovian conditioning and cumulative reinforcement rate.

    Science.gov (United States)

    Harris, Justin A; Patterson, Angela E; Gharaei, Saba

    2015-04-01

    In 5 experiments using delay conditioning of magazine approach with rats, reinforcement rate was varied either by manipulating the mean interval between onset of the conditioned stimulus (CS) and unconditioned stimulus (US) or by manipulating the proportion of CS presentations that ended with the US (trial-based reinforcement rate). Both manipulations influenced the acquisition of responding. In each experiment, a specific comparison was made between 2 CSs that differed in their mean CS-US interval and in their trial-based reinforcement rate, such that the cumulative reinforcement rate-the cumulative duration of the CS between reinforcements-was the same for the 2 CSs. For example, a CS reinforced on 100% of trials with a mean CS-US interval of 60 s was compared with a CS reinforced on 33% of trials and a mean duration of 20 s. Across the 5 experiments, conditioning was virtually identical for the 2 CSs with matched cumulative reinforcement rate. This was true as long as the timing of the US was unpredictable and, thus, response rates were uniform across the length of the CS. We conclude that the effects of CS-US interval and of trial-based reinforcement rate are reducible entirely to their common effect on cumulative reinforcement rate. We discuss the implications of this for rate-based, trial-based, and real-time associative models of conditioning.

  4. An Axiomatization of Cumulative Prospect Theory

    NARCIS (Netherlands)

    Wakker, P.P.; Tversky, A.

    1993-01-01

    This paper presents a method for axiomatizing a variety of models for decision making under uncertainty, including Expected Utility and Cumulative Prospect Theory. This method identifies, for each model, the situations that permit consistent inferences about the ordering of value differences. Exampl

  5. Cumulative Disadvantage among the Highly Ambitious.

    Science.gov (United States)

    McClelland, Katherine

    1990-01-01

    Using a social reproduction theory framework, analyzes the process by which high school seniors aspiring to high-level positions are sorted out after graduation. Analyzes early educational attainments and changes in occupational expectations. Shows a process of cumulative disadvantage in which White males are more likely to achieve their goals.…

  6. Neutron source capability assessment for cumulative fission yields measurements

    Energy Technology Data Exchange (ETDEWEB)

    Descalle, M A; Dekin, W; Kenneally, J

    2011-04-06

    A recent analysis of high-quality cumulative fission yields data for Pu-239 published in the peer-reviewed literature showed that the quoted experimental uncertainties do not allow a clear statement on how the fission yields vary as a function of energy. [Prussin2009] To make such a statement requires a set of experiments with well 'controlled' and understood sources of experimental errors to reduce uncertainties as low as possible, ideally in the 1 to 2% range. The Inter Laboratory Working Group (ILWOG) determined that Directed Stockpile Work (DSW) would benefit from an experimental program with the stated goal to reduce the measurement uncertainties significantly in order to make a definitive statement of the relationship of energy dependence to the cumulative fission yields. Following recent discussions between Lawrence Livermore National Laboratory (LLNL) and Los Alamos National Laboratory (LANL), there is a renewed interest in developing a concerted experimental program to measure fission yields in a neutron energy range from thermal energy (0.025 eV) to 14 MeV with an emphasis on discrete energies from 0.5 to 4 MeV. Ideally, fission yields would be measured at single energies, however, in practice there are only 'quasi-monoenergetic' neutrons sources of finite width. This report outlines a capability assessment as of June 2011 of available neutron sources that could be used as part of a concerted experimental program to measure cumulative fission yields. In a framework of international collaborations, capabilities available in the United States, at the Atomic Weapons Establishment (AWE) in the United Kingdom and at the Commissariat Energie Atomique (CEA) in France are listed. There is a need to develop an experimental program that will reduce the measurement uncertainties significantly in order to make a definitive statement of the relationship of energy dependence to the cumulative fission yields. Fission and monoenergetic neutron sources

  7. Complexity and demographic explanations of cumulative culture.

    Directory of Open Access Journals (Sweden)

    Adrien Querbes

    Full Text Available Formal models have linked prehistoric and historical instances of technological change (e.g., the Upper Paleolithic transition, cultural loss in Holocene Tasmania, scientific progress since the late nineteenth century to demographic change. According to these models, cumulation of technological complexity is inhibited by decreasing--while favoured by increasing--population levels. Here we show that these findings are contingent on how complexity is defined: demography plays a much more limited role in sustaining cumulative culture in case formal models deploy Herbert Simon's definition of complexity rather than the particular definitions of complexity hitherto assumed. Given that currently available empirical evidence doesn't afford discriminating proper from improper definitions of complexity, our robustness analyses put into question the force of recent demographic explanations of particular episodes of cultural change.

  8. Avoiding Program-Induced Cumulative Overload (PICO).

    Science.gov (United States)

    Orr, Robin; Knapik, Joseph J; Pope, Rodney

    2016-01-01

    This article defines the concept of program-induced cumulative overload (PICO), provides examples, and advises ways to mitigate the adverse effects. PICO is the excessive cumulative physical workload that can be imparted to military personnel by a military training program with an embedded physical training component. PICO can be acute (accumulating within a single day) or chronic (accumulating across the entirety of the program) and results in adverse outcomes for affected personnel, including detrimental fatigue, performance degradation, injuries, or illness. Strategies to mitigate PICO include focusing administration and logistic practices during the development and ongoing management of a trainee program and implementing known musculoskeletal injury prevention strategies. More training is not always better, and trainers need to consider the total amount of physical activity that military personnel experience across both operational training and physical training if PICO is to be mitigated.

  9. Sharing a quota on cumulative carbon emissions

    Science.gov (United States)

    Raupach, Michael R.; Davis, Steven J.; Peters, Glen P.; Andrew, Robbie M.; Canadell, Josep G.; Ciais, Philippe; Friedlingstein, Pierre; Jotzo, Frank; van Vuuren, Detlef P.; Le Quéré, Corinne

    2014-10-01

    Any limit on future global warming is associated with a quota on cumulative global CO2 emissions. We translate this global carbon quota to regional and national scales, on a spectrum of sharing principles that extends from continuation of the present distribution of emissions to an equal per-capita distribution of cumulative emissions. A blend of these endpoints emerges as the most viable option. For a carbon quota consistent with a 2 °C warming limit (relative to pre-industrial levels), the necessary long-term mitigation rates are very challenging (typically over 5% per year), both because of strong limits on future emissions from the global carbon quota and also the likely short-term persistence in emissions growth in many regions.

  10. Structural Vibration Monitoring Using Cumulative Spectral Analysis

    Directory of Open Access Journals (Sweden)

    Satoru Goto

    2013-01-01

    Full Text Available This paper describes a resonance decay estimation for structural health monitoring in the presence of nonstationary vibrations. In structural health monitoring, the structure's frequency response and resonant decay characteristics are very important for understanding how the structure changes. Cumulative spectral analysis (CSA estimates the frequency decay by using the impulse response. However, measuring the impulse response of buildings is impractical due to the need to shake the building itself. In a previous study, we reported on system damping monitoring using cumulative harmonic analysis (CHA, which is based on CSA. The current study describes scale model experiments on estimating the hidden resonance decay under non-stationary noise conditions by using CSA for structural condition monitoring.

  11. Cumulative carbon emissions and the Green Paradox

    OpenAIRE

    Ploeg, Frederick Van der

    2013-01-01

    The green paradox states that a gradually more ambitious climate policy such as a renewables subsidy or an anticipated carbon tax induces fossil fuel owners to extract more rapidly and accelerate global warming. However, if extraction becomes more costly as reserves are depleted, such policies also shorten the fossil fuel era, induce more fossil fuel to be left in the earth, and thus curb cumulative carbon emissions. These consequences are relevant, as global warming depends primarily on cumu...

  12. Expansive Soil Crack Depth under Cumulative Damage

    Directory of Open Access Journals (Sweden)

    Bei-xiao Shi

    2014-01-01

    Full Text Available The crack developing depth is a key problem to slope stability of the expansive soil and its project governance and the crack appears under the roles of dry-wet cycle and gradually develops. It is believed from the analysis that, because of its own cohesion, the expansive soil will have a certain amount of deformation under pulling stress but without cracks. The soil body will crack only when the deformation exceeds the ultimate tensile strain that causes cracks. And it is also believed that, due to the combined effect of various environmental factors, particularly changes of the internal water content, the inherent basic physical properties of expansive soil are weakened, and irreversible cumulative damages are eventually formed, resulting in the development of expansive soil cracks in depth. Starting from the perspective of volumetric strain that is caused by water loss, considering the influences of water loss rate and dry-wet cycle on crack developing depth, the crack developing depth calculation model which considers the water loss rate and the cumulative damages is established. Both the proposal of water loss rate and the application of cumulative damage theory to the expansive soil crack development problems try to avoid difficulties in matrix suction measurement, which will surely play a good role in promoting and improving the research of unsaturated expansive soil.

  13. EPA Workshop on Epigenetics and Cumulative Risk ...

    Science.gov (United States)

    Agenda Download the Workshop Agenda (PDF) The workshop included presentations and discussions by scientific experts pertaining to three topics (i.e., epigenetic changes associated with diverse stressors, key science considerations in understanding epigenetic changes, and practical application of epigenetic tools to address cumulative risks from environmental stressors), to address several questions under each topic, and included an opportunity for attendees to participate in break-out groups, provide comments and ask questions. Workshop Goals The workshop seeks to examine the opportunity for use of aggregate epigenetic change as an indicator in cumulative risk assessment for populations exposed to multiple stressors that affect epigenetic status. Epigenetic changes are specific molecular changes around DNA that alter expression of genes. Epigenetic changes include DNA methylation, formation of histone adducts, and changes in micro RNAs. Research today indicates that epigenetic changes are involved in many chronic diseases (cancer, cardiovascular disease, obesity, diabetes, mental health disorders, and asthma). Research has also linked a wide range of stressors including pollution and social factors with occurrence of epigenetic alterations. Epigenetic changes have the potential to reflect impacts of risk factors across multiple stages of life. Only recently receiving attention is the nexus between the factors of cumulative exposure to environmental

  14. Effective dose delivery in atmospheric pressure plasma jets for plasma medicine: a model predictive control approach

    Science.gov (United States)

    Gidon, Dogan; Graves, David B.; Mesbah, Ali

    2017-08-01

    Atmospheric pressure plasma jets (APPJs) have been identified as a promising tool for plasma medicine. This paper aims to demonstrate the importance of using model-based feedback control strategies for safe, reproducible, and therapeutically effective application of APPJs for dose delivery to a target substrate. Key challenges in model-based control of APPJs arise from: (i) the multivariable, nonlinear nature of system dynamics, (ii) the need for constraining the system operation within an operating region that ensures safe plasma treatment, and (iii) the cumulative, nondecreasing nature of dose metrics. To systematically address these challenges, we propose a model predictive control (MPC) strategy for real-time feedback control of a radio-frequency APPJ in argon. To this end, a lumped-parameter, physics-based model is developed for describing the jet dynamics. Cumulative dose metrics are defined for quantifying the thermal and nonthermal energy effects of the plasma on substrate. The closed-loop performance of the MPC strategy is compared to that of a basic proportional-integral control system. Simulation results indicate that the MPC stategy provides a versatile framework for dose delivery in the presence of disturbances, while the safety and practical constraints of the APPJ operation can be systematically handled. Model-based feedback control strategies can lead to unprecedented opportunities for effective dose delivery in plasma medicine.

  15. Cumulative stress in research animals: Telomere attrition as a biomarker in a welfare context?

    Science.gov (United States)

    Bateson, Melissa

    2016-02-01

    Progress in improving animal welfare is currently limited by the lack of objective methods for assessing lifetime experience. I propose that telomere attrition, a cellular biomarker of biological age, provides a molecular measure of cumulative experience that could be used to assess the welfare impact of husbandry regimes and/or experimental procedures on non-human animals. I review evidence from humans that telomere attrition is accelerated by negative experiences in a cumulative and dose-dependent manner, but that this attrition can be mitigated or even reversed by positive life-style interventions. Evidence from non-human animals suggests that despite some specific differences in telomere biology, stress-induced telomere attrition is a robust phenomenon, occurring in a range of species including mice and chickens. I conclude that telomere attrition apparently integrates positive and negative experience in an accessible common currency that translates readily to novel species--the Holy Grail of a cumulative welfare indicator.

  16. Cumulative risks of foster care placement for Danish children

    National Research Council Canada - National Science Library

    Fallesen, Peter; Emanuel, Natalia; Wildeman, Christopher

    2014-01-01

    Although recent research suggests that the cumulative risk of foster care placement is far higher for American children than originally suspected, little is known about the cumulative risk of foster...

  17. Recursive Numerical Evaluation of the Cumulative Bivariate Normal Distribution

    CERN Document Server

    Meyer, Christian

    2010-01-01

    We propose an algorithm for evaluation of the cumulative bivariate normal distribution, building upon Marsaglia's ideas for evaluation of the cumulative univariate normal distribution. The algorithm is mathematically transparent, delivers competitive performance and can easily be extended to arbitrary precision.

  18. Climate mitigation: sustainable preferences and cumulative carbon

    Science.gov (United States)

    Buckle, Simon

    2010-05-01

    We develop a stylized AK growth model with both climate damages to ecosystem goods and services and sustainable preferences that allow trade-offs between present discounted utility and long-run climate damages. The simplicity of the model permits analytical solutions. Concern for the long-term provides a strong driver for mitigation action. One plausible specification of sustainable preferences leads to the result that, for a range of initial parameter values, an optimizing agent would choose a level of cumulative carbon dioxide (CO2) emissions independent of initial production capital endowment and CO2 levels. There is no technological change so, for economies with sufficiently high initial capital and CO2 endowments, optimal mitigation will lead to disinvestment. For lower values of initial capital and/or CO2 levels, positive investment can be optimal, but still within the same overall level of cumulative emissions. One striking aspect of the model is the complexity of possible outcomes, in addition to these optimal solutions. We also identify a resource constrained region and several regions where climate damages exceed resources available for consumption. Other specifications of sustainable preferences are discussed, as is the case of a hard constraint on long-run damages. Scientists are currently highlighting the potential importance of the cumulative carbon emissions concept as a robust yet flexible target for climate policymakers. This paper shows that it also has an ethical interpretation: it embodies an implicit trade off in global welfare between present discounted welfare and long-term climate damages. We hope that further development of the ideas presented here might contribute to the research and policy debate on the critical areas of intra- and intergenerational welfare.

  19. Long and Short Term Cumulative Structural Priming Effects

    OpenAIRE

    Kaschak, Michael P.; Kutta, Timothy J.; Coyle, Jacqueline M.

    2012-01-01

    We present six experiments that examine cumulative structural priming effects (i.e., structural priming effects that accumulate across many utterances). Of particular interest is whether (1) cumulative priming effects transfer across language production tasks and (2) the transfer of cumulative priming effects across tasks persists over the course of a week. Our data suggest that cumulative structural priming effects do transfer across language production tasks (e.g., from written stem complet...

  20. Preserved cumulative semantic interference despite amnesia

    Directory of Open Access Journals (Sweden)

    Gary Michael Oppenheim

    2015-05-01

    As predicted by Oppenheim et al’s (2010 implicit incremental learning account, WRP’s BCN RTs demonstrated strong (and significant repetition priming and semantic blocking effects (Figure 1. Similar to typical results from neurally intact undergraduates, WRP took longer to name pictures presented in semantically homogeneous blocks than in heterogeneous blocks, an effect that increased with each cycle. This result challenges accounts that ascribe cumulative semantic interference in this task to explicit memory mechanisms, instead suggesting that the effect has the sort of implicit learning bases that are typically spared in hippocampal amnesia.

  1. Cumulant matching for independent source extraction.

    Science.gov (United States)

    Phlypo, Ronald; Zarzoso, Vicente; Comon, Pierre; Lemahieu, Ignace

    2008-01-01

    In this work we show how one can make use of priors on signal statistics under the form of cumulant guesses to extract an independent source from an observed mixture. The advantage of using statistical priors on the signal lies in the fact that no specific knowledge is needed about its temporal behavior, neither about its spatial distribution. We show that these statistics can be obtained either by reasoning on the theoretical values of a supposed waveform, either by using a subset of the observations from which we know that their statistics are merely hindered by interferences. Results on an electro-cardiographic recording confirm the above assumptions.

  2. A Missing Link in the Evolution of the Cumulative Recorder

    Science.gov (United States)

    Asano, Toshio; Lattal, Kennon A.

    2012-01-01

    A recently recovered cumulative recorder provides a missing link in the evolution of the cumulative recorder from a modified kymograph to a reliably operating, scientifically and commercially successful instrument. The recorder, the only physical evidence of such an early precommercial cumulative recorder yet found, was sent to Keio University in…

  3. Original and cumulative prospect theory: a discussion of empirical differences

    NARCIS (Netherlands)

    P.P. Wakker; H. Fennema

    1997-01-01

    This note discusses differences between prospect theory and cumulative prospect theory. It shows that cumulative prospect theory is not merely a formal correction of some theoretical problems in prospect theory, but it also gives different predictions. Experiments are described that favor cumulative

  4. Cumulative Environmental Management Association : Wood Buffalo Region

    Energy Technology Data Exchange (ETDEWEB)

    Friesen, B. [Syncrude Canada Ltd., Edmonton, AB (Canada)

    2001-07-01

    The recently announced oil sands development of the Wood Buffalo Region in Alberta was the focus of this power point presentation. Both mining and in situ development is expected to total $26 billion and 2.6 million barrels per day of bitumen production. This paper described the economic, social and environmental challenges facing the resource development of this region. In addition to the proposed oil sands projects, this region will accommodate the needs of conventional oil and gas production, forestry, building of pipelines and power lines, municipal development, recreation, tourism, mining exploration and open cast mining. The Cumulative Environmental Management Association (CEMA) was inaugurated as a non-profit association in April 2000, and includes 41 members from all sectors. Its major role is to ensure a sustainable ecosystem and to avoid any cumulative impacts on wildlife. Other work underway includes the study of soil and plant species diversity, and the effects of air emissions on human health, wildlife and vegetation. The bioaccumulation of heavy metals and their impacts on surface water and fish is also under consideration to ensure the quality and quantity of surface water and ground water. 3 figs.

  5. Cumulative environmental management and the oil sands

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2005-07-01

    In response to concerns regarding the cumulative environmental impacts of oil sands development within the Athabasca oil sands deposit, the government of Alberta established a Regional Sustainable Development Strategy (RSDS) to balance development with environmental protection. The environmental issues identified through the RSDS were addressed by the Cumulative Environmental Management Association (CEMA). CEMA's boundary is the Wood Buffalo region of northeastern Alberta. It identifies existing and future environmental effects in the region and proposes recommendations to regulatory bodies for reducing environmental impacts associated with oil sands development. This presentation outlined some of the 55 stakeholder representatives of CEMA, including Alberta government departments associated with resource development, oil sand developers within the region, and Aboriginal communities and First Nations. These stakeholders provide input on sector priorities and agree on environmental thresholds. Established working groups also address technical and scientific research issues identified in the RSDS such as sustainable ecosystems; surface waters; trace metals and air contaminants; nitrogen oxides and sulphur dioxides; and land reclamation. To date, CEMA has submitted more than 50 reports and has made 4 major environmental recommendations for trace metal management, ecosystem management tools, a framework for acid deposition management, and a landscape design checklist. tabs., figs.

  6. Higher Order Cumulants in Colorless Partonic Plasma

    CERN Document Server

    Cherif, S; Ladrem, M

    2016-01-01

    Any physical system considered to study the QCD deconfinement phase transition certainly has a finite volume, so the finite size effects are inevitably present. This renders the location of the phase transition and the determination of its order as an extremely difficult task, even in the simplest known cases. In order to identify and locate the colorless QCD deconfinement transition point in finite volume $T_{0}(V)$, a new approach based on the finite-size cumulant expansion of the order parameter and the $\\mathscr{L}_{m,n}$-Method is used.We have shown that both cumulants of higher order and their ratios, associated to the thermodynamical fluctuations of the order parameter, in QCD deconfinement phase transition behave in a particular enough way revealing pronounced oscillations in the transition region. The sign structure and the oscillatory behavior of these in the vicinity of the deconfinement phase transition point might be a sensitive probe and may allow one to elucidate their relation to the QCD phase...

  7. Innovativeness, population size and cumulative cultural evolution.

    Science.gov (United States)

    Kobayashi, Yutaka; Aoki, Kenichi

    2012-08-01

    Henrich [Henrich, J., 2004. Demography and cultural evolution: how adaptive cultural processes can produce maladaptive losses-the Tasmanian case. Am. Antiquity 69, 197-214] proposed a model designed to show that larger population size facilitates cumulative cultural evolution toward higher skill levels. In this model, each newborn attempts to imitate the most highly skilled individual of the parental generation by directly-biased social learning, but the skill level he/she acquires deviates probabilistically from that of the exemplar (cultural parent). The probability that the skill level of the imitator exceeds that of the exemplar can be regarded as the innovation rate. After reformulating Henrich's model rigorously, we introduce an overlapping-generations analog based on the Moran model and derive an approximate formula for the expected change per generation of the highest skill level in the population. For large population size, our overlapping-generations model predicts a much larger effect of population size than Henrich's discrete-generations model. We then investigate by way of Monte Carlo simulations the case where each newborn chooses as his/her exemplar the most highly skilled individual from among a limited number of acquaintances. When the number of acquaintances is small relative to the population size, we find that a change in the innovation rate contributes more than a proportional change in population size to the cumulative cultural evolution of skill level.

  8. Is uveitis associated with topiramate use? A cumulative review

    Directory of Open Access Journals (Sweden)

    Goldberg JL

    2016-08-01

    Full Text Available Jeffrey L Goldberg,1 Amy G Lau,2 Bo Fan,2 Lisa Ford,3 Howard E Greenberg3 1Byers Eye Institute, Stanford University, Palo Alto, CA, 2Janssen Research & Development, LLC, Horsham, PA, 3Janssen Research & Development, LLC, Titusville, NJ, USA Abstract: Occasional reports of uveitis following topiramate use necessitated an investigation of relevant cases from safety databases and published biomedical literature. Data mining of the Food and Drug Administration Adverse Event Reporting System and cumulative review of cases from the global safety database (sponsor database and published literature were conducted to assess association between topiramate use and uveitis. The Food and Drug Administration Adverse Event Reporting System search identified disproportional reporting of uveitis (n=23 and related terms (choroidal detachment, n=25; iridocyclitis, n=17. The postmarketing reporting frequency of uveitis and related events from the global safety database and based on an estimated topiramate exposure of 11,185,740 person-years from launch to April 2015 was 0.38 per 100,000 person-years and assigned as very rare. A total of 14 potential uveitis cases were identified from the cumulative review. Seven of these 14 cases were complicated by inadequate documentation, appearance of uveitic signs following drug withdrawal, or concurrent use of other sulfonamides. In acute angle-closure glaucoma and uveal effusions cases, insufficient evidence for underlying inflammation suggested that uveitis was not a component. Only seven of 14 cases were well documented, potentially topiramate-associated uveitis cases. Uveitis may occur in the setting of topiramate use only in very rare instances. Current evidence did not reveal a dose- or duration-dependent relationship between uveitis and topiramate use. Keywords: topiramate, uveitis, acute angle-closure glaucoma, drug safety, Food and Drug Administration Adverse Event Reporting System, postmarketing 

  9. Cumulative ionizing radiation exposure in patients with end stage kidney disease: a 6-year retrospective analysis.

    LENUS (Irish Health Repository)

    Coyle, Joe

    2011-08-13

    OBJECTIVE: To quantify cumulative exposure to ionizing radiation in patients with end stage kidney disease (ESKD). To investigate factors which may be independently associated with risk of high cumulative effective dose (CED). MATERIALS AND METHODS: The study had local institutional review board ethical approval. We conducted a retrospective study of 394 period prevalent ESKD patients attending a single tertiary referral centre between 2004 and 2009. Patient demographics were obtained from case records. Details of radiological investigations were obtained from the institutional radiology computerized database. CED was calculated using standard procedure specific radiation levels. High exposure was defined as CED > 50 mSv, an exposure which has been reported to increase cancer mortality by 5%. Data were compared using Pearson χ(2) and Mann-Whitney U test or Kruskal-Wallis tests. RESULTS: 394 patients were followed for a median of 4 years (1518 patient years follow-up). Of these 63% were male. Seventeen percent of patients had a CED of >50 mSv. Computed tomography (CT) accounted for 9% of total radiological studies\\/procedures while contributing 61.4% of total study dose. Median cumulative dose and median dose per patient year were significantly higher in the hemodialysis (HD) group (15.13 and 5.79 mSv, respectively) compared to the post-transplant group (2.9 and 0.52 mSv, respectively) (P < 0.001). CONCLUSION: ESKD patients are at risk of cumulative exposure to significant levels of diagnostic radiation. The majority of this exposure is imparted as a result of CT examinations to patients in the HD group.

  10. Repeated Radionuclide therapy in metastatic paraganglioma leading to the highest reported cumulative activity of 131I-MIBG

    Directory of Open Access Journals (Sweden)

    Ezziddin Samer

    2012-01-01

    Full Text Available Abstract 131I-MIBG therapy for neuroendocrine tumours may be dose limited. The common range of applied cumulative activities is 10-40 GBq. We report the uneventful cumulative administration of 111 GBq (= 3 Ci 131I-MIBG in a patient with metastatic paraganglioma. Ten courses of 131I-MIBG therapy were given within six years, accomplishing symptomatic, hormonal and tumour responses with no serious adverse effects. Chemotherapy with cisplatin/vinblastine/dacarbazine was the final treatment modality with temporary control of disease, but eventually the patient died of progression. The observed cumulative activity of 131I-MIBG represents the highest value reported to our knowledge, and even though 12.6 GBq of 90Y-DOTATOC were added intermediately, no associated relevant bone marrow, hepatic or other toxicity were observed. In an individual attempt to palliate metastatic disease high cumulative activity alone should not preclude the patient from repeat treatment.

  11. Ion cumulation by conical cathode electrolysis.

    CERN Document Server

    Grishin, V G

    2002-01-01

    Results of solid-state sodium stearate electrolysis with conical and cylindrical cathodes is presented here. Both electric measurement and conical samples destruction can be explained if a stress developing inside the conical sample is much bigger than in the cylindrical case and there is its unlimited amplification along cone slopes. OTHER KEYWORDS: ion, current, solid, symmetry, cumulation, polarization, depolarization, ionic conductor,superionic conductor, ice, crystal, strain, V-center, V-centre, doped crystal, interstitial impurity, intrinsic color center, high pressure technology, Bridgman, anvil, experiment, crowdion, dielectric, proton, layer, defect, lattice, dynamics, electromigration, mobility, muon catalysis, concentration, doping, dopant, conductivity, pycnonuclear reaction, permittivity, dielectric constant, point defects, interstitials, polarizability, imperfection, defect centers, glass, epitaxy, sodium hydroxide, metallic substrate, crystallization, point, tip, susceptibility, ferroelectric, ...

  12. [Cumulative trauma disorders: work or professional disease?].

    Science.gov (United States)

    de Carvalho, Marcus Vitor Diniz; Cavalcanti, Francisco Ivo Dantas; Soriano, Evelyne Pessoa; de Miranda, Hênio Ferreira

    2009-06-01

    This study aimed at reviewing the Brazilian legislation applied to occupational health. It refers to the diseases embodied in the Repetition Strain Injury (RSI) and Cumulative Trauma Disorders (CTD) regarded as work or professional diseases. This analysis allowed to perform the historical evolution of legislation concerning the issue, noting that the state of the art of regulation on RSI-CTD is anchored in specific regulation present in the Normative Instruction 98/2003, that establishes the diagnostic criteria and classification of RSI-CTD. It was concluded that according to the existing legislation in Brazil, the pathologies related to RSI-CTD are considered as work diseases and their legal effects are similar to the work-related accidents.

  13. Radiation dose monitoring in the clinical routine

    Energy Technology Data Exchange (ETDEWEB)

    Guberina, Nika [UK Essen (Germany). Radiology

    2017-04-15

    Here we describe the first clinical experiences regarding the use of an automated radiation dose management software to monitor the radiation dose of patients during routine examinations. Many software solutions for monitoring radiation dose have emerged in the last decade. The continuous progress in radiological techniques, new scan features, scanner generations and protocols are the primary challenge for radiation dose monitoring software systems. To simulate valid dose calculations, radiation dose monitoring systems have to follow current trends and stay constantly up-to-date. The dose management software is connected to all devices at our institute and conducts automatic data acquisition and radiation dose calculation. The system incorporates 18 virtual phantoms based on the Cristy phantom family, estimating doses in newborns to adults. Dose calculation relies on a Monte Carlo simulation engine. Our first practical experiences demonstrate that the software is capable of dose estimation in the clinical routine. Its implementation and use have some limitations that can be overcome. The software is promising and allows assessment of radiation doses, like organ and effective doses according to ICRP 60 and ICRP 103, patient radiation dose history and cumulative radiation doses. Furthermore, we are able to determine local diagnostic reference doses. The radiation dose monitoring software systems can facilitate networking between hospitals and radiological departments, thus refining radiation doses and implementing reference doses at substantially lower levels.

  14. Impact of Total Ionizing Dose Radiation Testing and Long-Term Thermal Cycling on the Operation of CMF20120D Silicon Carbide Power MOSFET

    Science.gov (United States)

    Patterson, Richard L.; Scheidegger, Robert J.; Lauenstein, Jean-Marie; Casey, Megan; Scheick, Leif; Hammoud, Ahmad

    2013-01-01

    Power systems designed for use in NASA space missions are required to work reliably under harsh conditions including radiation, thermal cycling, and extreme temperature exposures. Silicon carbide devices show great promise for use in future power electronics systems, but information pertaining to performance of the devices in the space environment is very scarce. A silicon carbide N-channel enhancement-mode power MOSFET called the CMF20120 is of interest for use in space environments. Samples of the device were exposed to radiation followed by long-term thermal cycling to address their reliability for use in space applications. The results of the experimental work are presentd and discussed.

  15. Bronchiolitis obliterans organizing pneumonia during low-dose amiodarone therapy

    NARCIS (Netherlands)

    Jessurun, GAJ; Hoogenberg, K; Crijns, HJGM

    1997-01-01

    Two cases of amiodarone-induced pulmonary toxicity during a relatively short period of low-dose amiodarone treatment are reported. The toxicity risk of amiodarone is determined by cumulative factors in individual patients.

  16. Bronchiolitis obliterans organizing pneumonia during low-dose amiodarone therapy

    NARCIS (Netherlands)

    Jessurun, GAJ; Hoogenberg, K; Crijns, HJGM

    Two cases of amiodarone-induced pulmonary toxicity during a relatively short period of low-dose amiodarone treatment are reported. The toxicity risk of amiodarone is determined by cumulative factors in individual patients.

  17. Long and Short Term Cumulative Structural Priming Effects.

    Science.gov (United States)

    Kaschak, Michael P; Kutta, Timothy J; Coyle, Jacqueline M

    We present six experiments that examine cumulative structural priming effects (i.e., structural priming effects that accumulate across many utterances). Of particular interest is whether (1) cumulative priming effects transfer across language production tasks and (2) the transfer of cumulative priming effects across tasks persists over the course of a week. Our data suggest that cumulative structural priming effects do transfer across language production tasks (e.g., from written stem completion to picture description, and from picture description to written stem completion), but only when both tasks are presented in the same experimental session. When cumulative priming effects are established in one task, and the second (changed) task is not presented until a week later, the cumulative priming effects are not observed.

  18. Why Veterinary Medical Educators Should Embrace Cumulative Final Exams.

    Science.gov (United States)

    Royal, Kenneth D

    2017-01-03

    The topic of cumulative final examinations often elicits polarizing opinions from veterinary medical educators. While some faculty prefer cumulative finals, there are many who perceive these types of examinations as problematic. Specifically, faculty often cite cumulative examinations are more likely to cause students' greater stress, which may in turn result in negative student evaluations of teaching. Cumulative finals also restrict the number of items one may present to students on most recent material. While these cited disadvantages may have some merit, the advantages of cumulative examinations far exceed the disadvantages. The purpose of this article is to discuss the advantages of cumulative examinations with respect to learning evidence, grade/score validity, fairness issues, and implications for academic policy.

  19. Effects of target-controlled infusion of high-dose naloxone on pain and hyperalgesia in a human thermal injury model: a study protocol: A randomized, double-blind, placebo-controlled, crossover trial with an enriched design.

    Science.gov (United States)

    Springborg, Anders D; Jensen, Elisabeth K; Taylor, Bradley K; Werner, Mads U

    2016-11-01

    Mu-opioid-receptor antagonists have been extensively studied in experimental research as pharmacological tools uncovering mechanisms of pain modulation by the endogenous opioid system. In rodents, administration of high doses of mu-opioid-receptor antagonists after the resolution of an inflammatory injury has demonstrated reinstatement of nociceptive hypersensitivity indicating unmasking of latent sensitization. In a recent human study, pain hypersensitivity assessed as secondary hyperalgesia area (SHA), was reinstated 7 days after a mild thermal injury, in 4 out of 12 subjects after a naloxone infusion.The aims of the present study are first, to replicate our previous findings in a larger-sized study; second, to examine if high sensitizers (subjects presenting with large SHA after a thermal injury) develop a higher degree of hypersensitivity after naloxone challenge than low sensitizers (subjects presenting with restricted SHA after a thermal injury); and third to examine a dose-response relationship between 3 stable naloxone concentrations controlled by target-controlled infusion, and the unmasking of latent sensitization.Healthy participants (n = 80) underwent a screening day (day 0) with induction of a thermal skin injury (47°C, 420 seconds, 12.5 cm). Assessment of SHA was performed 1 and 2 hours after the injury. Using an enriched design, only participants belonging to the upper quartile of SHA (Q4, high sensitizers; n = 20) and the lower quartile of SHA (Q1, low sensitizers; n = 20) continued the study, comprising 4 consecutive days-days 1 to 4. Thermal skin injuries were repeated on day 1 and day 3, whereas day 2 and day 4 (7 days after day 1 and day 3, respectively) were target-controlled infusion days in which the subjects were randomly allocated to receive either naloxone (3.25 mg/kg, 4 mg/mL) or placebo (normal saline) intravenous. The primary outcome was SHA assessed by weighted-pin instrument (128 mN) 0, 1, 2, and 165 to 169

  20. Analysis of experimental data on correlations between cumulative particles

    Energy Technology Data Exchange (ETDEWEB)

    Vlasov, A.V.; Doroshkevich, E.A.; Leksin, G.A. [Institute of Theoretical and Experimental Physics, Moscow (Russian Federation)] [and others

    1995-04-01

    Experimental data on correlations between cumulative particles are analyzed. A space-time and energy-transfer pattern of hadron-nucleus interaction based on both correlation data and data on the inclusive spectra of cumulative particles is considered. A new variable that is convenient for describing the production of cumulative particles is proposed using the concept of symmetry between the one-particle and multiparticle distributions. 32 refs., 9 figs., 1 tab.

  1. Analysis of Memory Codes and Cumulative Rehearsal in Observational Learning

    Science.gov (United States)

    Bandura, Albert; And Others

    1974-01-01

    The present study examined the influence of memory codes varying in meaningfulness and retrievability and cumulative rehearsal on retention of observationally learned responses over increasing temporal intervals. (Editor)

  2. Continuously Cumulating Meta-Analysis and Replicability.

    Science.gov (United States)

    Braver, Sanford L; Thoemmes, Felix J; Rosenthal, Robert

    2014-05-01

    The current crisis in scientific psychology about whether our findings are irreproducible was presaged years ago by Tversky and Kahneman (1971), who noted that even sophisticated researchers believe in the fallacious Law of Small Numbers-erroneous intuitions about how imprecisely sample data reflect population phenomena. Combined with the low power of most current work, this often leads to the use of misleading criteria about whether an effect has replicated. Rosenthal (1990) suggested more appropriate criteria, here labeled the continuously cumulating meta-analytic (CCMA) approach. For example, a CCMA analysis on a replication attempt that does not reach significance might nonetheless provide more, not less, evidence that the effect is real. Alternatively, measures of heterogeneity might show that two studies that differ in whether they are significant might have only trivially different effect sizes. We present a nontechnical introduction to the CCMA framework (referencing relevant software), and then explain how it can be used to address aspects of replicability or more generally to assess quantitative evidence from numerous studies. We then present some examples and simulation results using the CCMA approach that show how the combination of evidence can yield improved results over the consideration of single studies.

  3. Effects of target-controlled infusion of high-dose naloxone on pain and hyperalgesia in a human thermal injury model

    DEFF Research Database (Denmark)

    Springborg, Anders D; Jensen, Elisabeth K; Taylor, Bradley K

    2016-01-01

    ) with induction of a thermal skin injury (47°C, 420 seconds, 12.5 cm). Assessment of SHA was performed 1 and 2 hours after the injury. Using an enriched design, only participants belonging to the upper quartile of SHA (Q4, high sensitizers; n = 20) and the lower quartile of SHA (Q1, low sensitizers; n = 20...

  4. The effect of incremental gamma-ray doses and incremental neutron fluences upon the performance of self-biased sup 1 sup 0 B-coated high-purity epitaxial GaAs thermal neutron detectors

    CERN Document Server

    Gersch, H K; Simpson, P A

    2002-01-01

    High-purity epitaxial GaAs sup 1 sup 0 B-coated thermal neutron detectors advantageously operate at room temperature without externally applied voltage. Sample detectors were systematically irradiated at fixed grid locations near the core of a 2 MW research reactor to determine their operational neutron dose threshold. Reactor pool locations were assigned so that fast and thermal neutron fluxes to the devices were similar. Neutron fluences ranged between 10 sup 1 sup 1 and 10 sup 1 sup 4 n/cm sup 2. GaAs detectors were exposed to exponential fluences of base ten. Ten detector designs were irradiated and studied, differentiated between p-i-n diodes and Schottky barrier diodes. The irradiated sup 1 sup 0 B-coated detectors were tested for neutron detection sensitivity in a thermalized neutron beam. Little damage was observed for detectors irradiated at neutron fluences of 10 sup 1 sup 2 n/cm sup 2 and below, but signals noticeably degraded at fluences of 10 sup 1 sup 3 n/cm sup 2. Catastrophic damage was appare...

  5. Cumulative Effect of Depression on Dementia Risk

    Directory of Open Access Journals (Sweden)

    J. Olazarán

    2013-01-01

    Full Text Available Objective. To analyze a potential cumulative effect of life-time depression on dementia and Alzheimer’s disease (AD, with control of vascular factors (VFs. Methods. This study was a subanalysis of the Neurological Disorders in Central Spain (NEDICES study. Past and present depression, VFs, dementia status, and dementia due to AD were documented at study inception. Dementia status was also documented after three years. Four groups were created according to baseline data: never depression (nD, past depression (pD, present depression (prD, and present and past depression (prpD. Logistic regression was used. Results. Data of 1,807 subjects were investigated at baseline (mean age 74.3, 59.3% women, and 1,376 (81.6% subjects were evaluated after three years. The prevalence of dementia at baseline was 6.7%, and dementia incidence was 6.3%. An effect of depression was observed on dementia prevalence (OR [CI 95%] 1.84 [1.01–3.35] for prD and 2.73 [1.08–6.87] for prpD, and on dementia due to AD (OR 1.98 [0.98–3.99] for prD and OR 3.98 [1.48–10.71] for prpD (fully adjusted models, nD as reference. Depression did not influence dementia incidence. Conclusions. Present depression and, particularly, present and past depression are associated with dementia at old age. Multiple mechanisms, including toxic effect of depression on hippocampal neurons, plausibly explain these associations.

  6. Cumulative social disadvantage and child health.

    Science.gov (United States)

    Bauman, Laurie J; Silver, Ellen J; Stein, Ruth E K

    2006-04-01

    Disparities in child health are a major public health concern. However, it is unclear whether these are predominantly the result of low income, race, or other social risk factors that may contribute to their health disadvantage. Although others have examined the effects of the accumulation of risk factors, this methodology has not been applied to child health. We tested 4 social risk factors (poverty, minority race/ethnicity, low parental education, and not living with both biological parents) to assess whether they have cumulative effects on child health and examined whether access to health care reduced health disparities. We analyzed data on 57,553 children low parental education, and single-parent household) were consistently associated with child health. These were summed, generating the Social Disadvantage Index (range: 0-3). A total of 43.6% of children had no social disadvantages, 30.8% had 1, 15.6% had 2, and 10.0% had all 3. Compared with those with no social disadvantages, the odds ratios (ORs) of being in "good, fair, or poor health" (versus "excellent or very good") were 1.95 for 1 risk, 3.22 for 2 risks, and 4.06 for 3 risks. ORs of having a chronic condition increased from 1.25 (1 risk) to 1.60 (2 risks) to 2.11 (3 risks). ORs for activity limitation were 1.51 (1 risk) to 2.14 (2 risks) and 2.88 (3 risks). Controlling for health insurance did not affect these findings. The accumulation of social disadvantage among children was strongly associated with poorer child health and having insurance did not reduce the observed health disparities.

  7. A Framework for Treating Cumulative Trauma with Art Therapy

    Science.gov (United States)

    Naff, Kristina

    2014-01-01

    Cumulative trauma is relatively undocumented in art therapy practice, although there is growing evidence that art therapy provides distinct benefits for resolving various traumas. This qualitative study proposes an art therapy treatment framework for cumulative trauma derived from semi-structured interviews with three art therapists and artistic…

  8. Cumulative Effects of Human Activities on Marine Mammal Populations

    Science.gov (United States)

    2015-09-30

    1 DISTRIBUTION STATEMENT A. Approved for public release; distribution is unlimited. Cumulative Effects of Human Activities on Marine Mammal ...marine mammals . OBJECTIVES The National Academies of Sciences, Engineering, and Medicine has convened a volunteer committee that will...Review the present scientific understanding of cumulative effects of anthropogenic stressors on marine mammals with a focus on anthropogenic sound

  9. A Framework for Treating Cumulative Trauma with Art Therapy

    Science.gov (United States)

    Naff, Kristina

    2014-01-01

    Cumulative trauma is relatively undocumented in art therapy practice, although there is growing evidence that art therapy provides distinct benefits for resolving various traumas. This qualitative study proposes an art therapy treatment framework for cumulative trauma derived from semi-structured interviews with three art therapists and artistic…

  10. Cumulative Estrogen Exposure and Prospective Memory in Older Women

    Science.gov (United States)

    Hesson, Jacqueline

    2012-01-01

    This study looked at cumulative lifetime estrogen exposure, as estimated with a mathematical index (Index of Cumulative Estrogen Exposure (ICEE)) that included variables (length of time on estrogen therapy, age at menarche and menopause, postmenopausal body mass index, time since menopause, nulliparity and duration of breastfeeding) known to…

  11. A new family of cumulative indexes for measuring scientific performance.

    Directory of Open Access Journals (Sweden)

    Marcin Kozak

    Full Text Available In this paper we propose a new family of cumulative indexes for measuring scientific performance which can be applied to many metrics, including h index and its variants (here we apply it to the h index, h(2 index and Google Scholar's i10 index. These indexes follow the general principle of repeating the index calculation for the same publication set. Using bibliometric data and reviewer scores for accepted and rejected fellowship applicants we examine how valid the cumulative variant is compared to the original variant. These analyses showed that the cumulative indexes result in higher correlations with the reviewer scores than their original variants. Thus, the cumulative indexes better reflect the assessments by peers than the original variants and are useful extensions of the original indexes. In contrast to many other measures of scientific performance proposed up to now, the cumulative indexes seem not only to be effective, but they are also easy to understand and calculate.

  12. A bivariate optimal replacement policy with cumulative repair cost limit under cumulative damage model

    Indian Academy of Sciences (India)

    MIN-T SAI LAI; SHIH-CHIH CHEN

    2016-05-01

    In this paper, a bivariate replacement policy (n, T) for a cumulative shock damage process is presented that included the concept of cumulative repair cost limit. The arrival shocks can be divided into two kinds of shocks. Each type-I shock causes a random amount of damage and these damages are additive. When the total damage exceeds a failure level, the system goes into serious failure. Type-II shock causes the system into minor failure and such a failure can be corrected by minimal repair. When a minor failure occurs, the repaircost will be evaluated and minimal repair is executed if the accumulated repair cost is less than a predetermined limit L. The system is replaced at scheduled time T, at n-th minor failure, or at serious failure. The long-term expected cost per unit time is derived using the expected costs as the optimality criterion. The minimum-cost policy is derived, and existence and uniqueness of the optimal n* and T* are proved. This bivariate optimal replacement policy (n, T) is showed to be better than the optimal T* and the optimal n* policy.

  13. Longhi Games, Internal Reservoirs, and Cumulate Porosity

    Science.gov (United States)

    Morse, S. A.

    2009-05-01

    Fe in plagioclase at an early age, T-rollers (or not) on the Di-Trid boundary in Fo-Di-Sil, the mantle solidus, origins of anorthosites, esoteric uses of Schreinemakers rules and many more topics are all fresh and pleasant memories of John Longhi's prolific and creative work. The Fram-Longhi experimental effect of pressure on plagioclase partitioning with liquid in mafic rocks became essential to an understanding of multiphase Rayleigh fractionation of plagioclase in big layered intrusions. Only by using the pressure effect could I find a good equation through the data for the Kiglapait intrusion, and that result among others required the existence with probability 1.0 of an internal reservoir (Morse, JPet 2008). Knowledge of cumulate porosity is a crucial key to the understanding of layered igneous rocks. We seek both the initial (inverse packing fraction) and residual porosity to find the time and process path from sedimentation to solidification. In the Kiglapait Lower Zone we have a robust estimate of mean residual porosity from the modes of the excluded phases augite, oxides, sulfide, and apatite. To this we apply the maximum variance of plagioclase composition (the An range) to find an algorithm that extends through the Upper Zone and to other intrusions. Of great importance is that all these measurements were made in grain mounts concentrated from typically about 200 g of core or hand specimen, hence the represented sample volume is thousands of times greater than for a thin section. The resulting distribution and scatter of the An range is novel and remarkable. It is V-shaped in the logarithmic representation of stratigraphic height, running from about 20 mole % at both ends (base to top of the Layered Series) to near-zero at 99 PCS. The intercept of the porosity-An range relation gives An range = 3.5 % at zero residual porosity. Petrographic analysis reveals that for PCS less than 95 and greater than 99.9, the An range is intrinsic, i.e. pre-cumulus, for

  14. Cumulative stress and autonomic dysregulation in a community sample.

    Science.gov (United States)

    Lampert, Rachel; Tuit, Keri; Hong, Kwang-Ik; Donovan, Theresa; Lee, Forrester; Sinha, Rajita

    2016-05-01

    Whether cumulative stress, including both chronic stress and adverse life events, is associated with decreased heart rate variability (HRV), a non-invasive measure of autonomic status which predicts poor cardiovascular outcomes, is unknown. Healthy community dwelling volunteers (N = 157, mean age 29 years) participated in the Cumulative Stress/Adversity Interview (CAI), a 140-item event interview measuring cumulative adversity including major life events, life trauma, recent life events and chronic stressors, and underwent 24-h ambulatory ECG monitoring. HRV was analyzed in the frequency domain and standard deviation of NN intervals (SDNN) calculated. Initial simple regression analyses revealed that total cumulative stress score, chronic stressors and cumulative adverse life events (CALE) were all inversely associated with ultra low-frequency (ULF), very low-frequency (VLF) and low-frequency (LF) power and SDNN (all p stress and chronic stress each was significantly associated with SDNN and ULF even after the highly significant contributions of age and sex, with no other covariates accounting for additional appreciable variance. For VLF and LF, both total cumulative stress and chronic stress significantly contributed to the variance alone but were not longer significant after adjusting for race and health behaviors. In summary, total cumulative stress, and its components of adverse life events and chronic stress were associated with decreased cardiac autonomic function as measured by HRV. Findings suggest one potential mechanism by which stress may exert adverse effects on mortality in healthy individuals. Primary preventive strategies including stress management may prove beneficial.

  15. Methods of calculating radiation absorbed dose.

    Science.gov (United States)

    Wegst, A V

    1987-01-01

    The new tumoricidal radioactive agents being developed will require a careful estimate of radiation absorbed tumor and critical organ dose for each patient. Clinical methods will need to be developed using standard imaging or counting instruments to determine cumulated organ activities with tracer amounts before the therapeutic administration of the material. Standard MIRD dosimetry methods can then be applied.

  16. Thermal Analysis of Whole Bacterial Cells Exposed to Potassium Permanganate Using Differential Scanning Calorimetry: a Biphasic Dose-Dependent Response to Stress

    Directory of Open Access Journals (Sweden)

    Marina K. Abuladze

    2009-01-01

    Full Text Available Differential scanning calorimetry (DSC was applied to estimate the impact of the toxic oxidant potassium permanganate (PM on the intracellular structural and functional alterations at whole cell level using soil bacteria Arthrobacter oxydans as a model culture. Differential scanning calorimetry (DSC was applied in order to estimate the impact of the toxic oxidant potassium permanganate (PM on the intracellular structural and functional alterations at the whole cell level using the soil bacteria Arthrobacter oxydans as a model culture. We compared the total melting heat and the temperature of DNA-protein complex (DNP melting at the PM application prior to the calorimetry measurement and after 24-h exposure at the concentration range 0.02–1.4 mM. The initial oxidative effect caused changes in the pattern of the whole cell melting spectra (mainly at the temperature range 56–78°C, the decrease of Tmax °C DNP melting, and did not influence significantly the total heat of bacterial melting at different concentrations of PM. The prolonged effect of permanganate up to 24 h was characterized by a biphasic dose-dependent response to stress estimated by the DSC technique and the colony-forming assay. The low doses of PM (0.02 and 0.2 mM stimulated cell proliferation, and increased the total whole cell melting heat and the temperature of DNP melting. The toxic effect of PM up to 0.04 mM reduced cell viability, changed the character of multipeaked thermograms, and lowered the total melting heat and the temperature of DNP melting in a concentration-dependent manner. This study presents the DSC method for evaluating and monitoring the effects of exposure to potential human and environmental toxicants.

  17. Entanglement entropy and particle number cumulants of disordered fermions

    Science.gov (United States)

    Burmistrov, I. S.; Tikhonov, K. S.; Gornyi, I. V.; Mirlin, A. D.

    2017-08-01

    We study the entanglement entropy and particle number cumulants for a system of disordered noninteracting fermions in d dimensions. We show, both analytically and numerically, that for a weak disorder the entanglement entropy and the second cumulant (particle number variance) are proportional to each other with a universal coefficient. The corresponding expressions are analogous to those in the clean case but with a logarithmic factor regularized by the mean free path rather than by the system size. We also determine the scaling of higher cumulants by analytical (weak disorder) and numerical means. Finally, we predict that the particle number variance and the entanglement entropy are nonanalytic functions of disorder at the Anderson transition.

  18. EPA's SHEDS-multimedia model: children's cumulative pyrethroid exposure estimates and evaluation against NHANES biomarker data.

    Science.gov (United States)

    Xue, Jianping; Zartarian, Valerie; Tornero-Velez, Rogelio; Tulve, Nicolle S

    2014-12-01

    The U.S. EPA's SHEDS-Multimedia model was applied to enhance the understanding of children's exposures and doses to multiple pyrethroid pesticides, including major contributing chemicals and pathways. This paper presents combined dietary and residential exposure estimates and cumulative doses for seven commonly used pyrethroids, and comparisons of model evaluation results with NHANES biomarker data for 3-PBA and DCCA metabolites. Model input distributions were fit to publicly available pesticide usage survey data, NHANES, and other studies, then SHEDS-Multimedia was applied to estimate total pyrethroid exposures and doses for 3-5 year olds for one year variability simulations. For dose estimations we used a pharmacokinetic model and two approaches for simulating dermal absorption. SHEDS-Multimedia predictions compared well to NHANES biomarker data: ratios of 3-PBA observed data to SHEDS-Multimedia modeled results were 0.88, 0.51, 0.54 and 1.02 for mean, median, 95th, and 99th percentiles, respectively; for DCCA, the ratios were 0.82, 0.53, 0.56, and 0.94. Modeled time-averaged cumulative absorbed dose of the seven pyrethroids was 3.1 nmol/day (versus 8.4 nmol/day for adults) in the general population (residential pyrethroid use and non-use homes) and 6.7 nmol/day (versus 10.5 nmol/day for adults) in the simulated residential pyrethroid use population. For the general population, contributions to modeled cumulative dose by chemical were permethrin (60%), cypermethrin (22%), and cyfluthrin (16%); for residential use homes, contributions were cypermethrin (49%), permethrin (29%), and cyfluthrin (17%). The primary exposure route for 3-5 year olds in the simulated residential use population was non-dietary ingestion exposure; whereas for the simulated general population, dietary exposure was the primary exposure route. Below the 95th percentile, the major exposure pathway was dietary for the general population; non-dietary ingestion was the major pathway starting below

  19. Online Scheduling in Manufacturing A Cumulative Delay Approach

    CERN Document Server

    Suwa, Haruhiko

    2013-01-01

    Online scheduling is recognized as the crucial decision-making process of production control at a phase of “being in production" according to the released shop floor schedule. Online scheduling can be also considered as one of key enablers to realize prompt capable-to-promise as well as available-to-promise to customers along with reducing production lead times under recent globalized competitive markets. Online Scheduling in Manufacturing introduces new approaches to online scheduling based on a concept of cumulative delay. The cumulative delay is regarded as consolidated information of uncertainties under a dynamic environment in manufacturing and can be collected constantly without much effort at any points in time during a schedule execution. In this approach, the cumulative delay of the schedule has the important role of a criterion for making a decision whether or not a schedule revision is carried out. The cumulative delay approach to trigger schedule revisions has the following capabilities for the ...

  20. Cumulative Risks of Foster Care Placement for Danish Children

    DEFF Research Database (Denmark)

    Fallesen, Peter; Emanuel, Natalia; Wildeman, Christopher

    2014-01-01

    Although recent research suggests that the cumulative risk of foster care placement is far higher for American children than originally suspected, little is known about the cumulative risk of foster care placement in other countries, which makes it difficult to gauge the degree to which factor...... is for Danish children. Results suggest that at the beginning of the study period (in 1998) the cumulative risk of foster care placement for Danish children was roughly in line with the risk for American children. Yet, by the end of the study period (2010), the risk had declined to half the risk for American...... foster care placement is salient in other contexts. In this article, we provide companion estimates to those provided in recent work on the US by using Danish registry data and synthetic cohort life tables to show how high and unequally distributed the cumulative risk of foster care placement...

  1. Mapping cumulative human impacts in the eastern North Sea

    DEFF Research Database (Denmark)

    Stock, A.; Andersen, Jesper; Heinänen, S.

    of the MSFD; and 3) to deepen the understanding of how errors in expert judgment affect the resulting cumulative human impact maps by means of Monte Carlo simulations. We combined existing data sets on the spatial distribution of 33 anthropogenic stressors (linked to the MSFD pressures) and 28 key habitats....... In contrast, the predicted impacts for much of the Norwegian EEZ and areas far offshore were lower. The Monte Carlo simulations confirmed earlier findings that mapping cumulative impacts is generally "robust", but also showed that specific combinations of errors can seriously change local and regional...... on marine ecosystems have only recently been developed. The aims of our study were: 1) to develop a map of cumulative human impacts for the Danish, Swedish, Norwegian and German parts of the Greater North Sea; 2) to adjust the existing methods for mapping cumulative human impacts to fit the requirements...

  2. Cumulative Production Per Township - SaMiRa

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This dataset contains a selected township grid within the Sagebrush Mineral Resource Assessment project (SaMiRa) study area attributed with cumulative oil and gas...

  3. Macroscopic cumulative fatigue damage of material under nonsymmetrical cycle

    Institute of Scientific and Technical Information of China (English)

    盖秉政

    2002-01-01

    Hashin's macroscopic theory of fatigue damage is further discussed and a new method has been proposed for prediction of cumulative fatigue damage of material and its lifetime under nonsymmetrical cyclic loading.

  4. Translation-Invariant Representation for Cumulative Foot Pressure Images

    CERN Document Server

    Zheng, Shuai; Tan, Tieniu

    2010-01-01

    Human can be distinguished by different limb movements and unique ground reaction force. Cumulative foot pressure image is a 2-D cumulative ground reaction force during one gait cycle. Although it contains pressure spatial distribution information and pressure temporal distribution information, it suffers from several problems including different shoes and noise, when putting it into practice as a new biometric for pedestrian identification. In this paper, we propose a hierarchical translation-invariant representation for cumulative foot pressure images, inspired by the success of Convolutional deep belief network for digital classification. Key contribution in our approach is discriminative hierarchical sparse coding scheme which helps to learn useful discriminative high-level visual features. Based on the feature representation of cumulative foot pressure images, we develop a pedestrian recognition system which is invariant to three different shoes and slight local shape change. Experiments are conducted on...

  5. Some Characterization Results on Dynamic Cumulative Residual Tsallis Entropy

    Directory of Open Access Journals (Sweden)

    Madan Mohan Sati

    2015-01-01

    Full Text Available We propose a generalized cumulative residual information measure based on Tsallis entropy and its dynamic version. We study the characterizations of the proposed information measure and define new classes of life distributions based on this measure. Some applications are provided in relation to weighted and equilibrium probability models. Finally the empirical cumulative Tsallis entropy is proposed to estimate the new information measure.

  6. Steps and pips in the history of the cumulative recorder.

    OpenAIRE

    Lattal, Kennon A.

    2004-01-01

    From its inception in the 1930s until very recent times, the cumulative recorder was the most widely used measurement instrument in the experimental analysis of behavior. It was an essential instrument in the discovery and analysis of schedules of reinforcement, providing the first real-time analysis of operant response rates and patterns. This review traces the evolution of the cumulative recorder from Skinner's early modified kymographs through various models developed by Skinner and his co...

  7. Childhood Cumulative Risk Exposure and Adult Amygdala Volume and Function.

    Science.gov (United States)

    Evans, Gary W; Swain, James E; King, Anthony P; Wang, Xin; Javanbakht, Arash; Ho, S Shaun; Angstadt, Michael; Phan, K Luan; Xie, Hong; Liberzon, Israel

    2016-06-01

    Considerable work indicates that early cumulative risk exposure is aversive to human development, but very little research has examined the neurological underpinnings of these robust findings. This study investigates amygdala volume and reactivity to facial stimuli among adults (mean 23.7 years of age, n = 54) as a function of cumulative risk exposure during childhood (9 and 13 years of age). In addition, we test to determine whether expected cumulative risk elevations in amygdala volume would mediate functional reactivity of the amygdala during socioemotional processing. Risks included substandard housing quality, noise, crowding, family turmoil, child separation from family, and violence. Total and left hemisphere adult amygdala volumes were positively related to cumulative risk exposure during childhood. The links between childhood cumulative risk exposure and elevated amygdala responses to emotionally neutral facial stimuli in adulthood were mediated by the corresponding amygdala volumes. Cumulative risk exposure in later adolescence (17 years of age), however, was unrelated to subsequent adult amygdala volume or function. Physical and socioemotional risk exposures early in life appear to alter amygdala development, rendering adults more reactive to ambiguous stimuli such as neutral faces. These stress-related differences in childhood amygdala development might contribute to the well-documented psychological distress as a function of early risk exposure.

  8. Analysis of recovery process of low-dose neutron irradiation-induced defects in silicon nitride-based ceramics by thermal annealing

    Energy Technology Data Exchange (ETDEWEB)

    Rueanngoen, Areerak, E-mail: areerak_k@yahoo.com [Department of Nuclear Engineering, Graduate School of Science and Engineering, Tokyo Institute of Technology, O-okayama, Meguro-ku, Tokyo 152-8550 (Japan); Kanazawa, Koumei [Department of Nuclear Engineering, Graduate School of Science and Engineering, Tokyo Institute of Technology, O-okayama, Meguro-ku, Tokyo 152-8550 (Japan); Imai, Masamitsu; Yoshida, Katsumi; Yano, Toyohiko [Research Laboratory for Nuclear Reactors, Tokyo Institute of Technology, O-okayama, Meguro-ku, Tokyo 152-8550 (Japan)

    2014-12-15

    Two kinds of silicon nitride ceramics consisting of different polymorphs were neutron-irradiated up to 8.5 × 10{sup 24} n/m{sup 2} (E > 0.1 MeV) at 563 K, and their annealing behaviors were compared to those of previously reported SiAlON polymorphs subjected to the same irradiation condition. The macroscopic length change of α- and β-Si{sub 3}N{sub 4} and α- and β-SiAlON were 0.11%, 0.06%, 0.12% and 0.14%, respectively. Based on swelling data and microstructural observations, the low dose neutron irradiation-induced defects in silicon nitride-based ceramics were considered to be primarily point defects. In order to investigate the kinetics of defect recovery, these irradiated specimens were isothermally and isochronally annealed continuously up to 1473 K. Macroscopic length change decreased gradually with increasing annealing temperature. Recovery curves of isochronal annealing of α-Si{sub 3}N{sub 4} and α-SiAlON were similar, and those of β-Si{sub 3}N{sub 4} and β-SiAlON were also similar. The recombination rate constant as a first-order reaction increased with the increasing of the isothermal annealing temperature. A two-stage recovery process was considered between the irradiation temperature and 1473 K. The activation energies at higher temperatures were almost double those at lower temperatures in both Si{sub 3}N{sub 4} and SiAlON. At lower temperatures range the recovery should occur by annihilation of close-spaced Frenkel pairs. On the other hand, at higher temperatures, the recovery process may be governed by the annihilation of separated Frenkel pairs. In addition, the activation energies for defect recovery in Si{sub 3}N{sub 4} were larger than defects in SiAlON. Recovery characteristics of α- and β-phases were different in both crystals that are suggested to be due to differences in crystal structures.

  9. From image-guided radiotherapy to dose-guided radiotherapy; De la radiotherapie guidee par l'image a la radiotherapie guidee par la dose

    Energy Technology Data Exchange (ETDEWEB)

    Cazoulat, G.; Lesaunier, M.; Simon, A.; Haigron, P.; Acosta, O. [Inserm, U642, 35000 Rennes (France); LTSI, universite de Rennes-1, 35000 Rennes (France); Louvel, G.; Chajon, E.; Leseur, J. [Centre Eugene-Marquis, rue de La-Bataille-Flandres-Dunkerque, CS 44229, 35042 Rennes cedex (France); Lafond, C.; De Crevoisier, R. [Inserm, U642, 35000 Rennes (France); LTSI, universite de Rennes-1, 35000 Rennes (France); Centre Eugene-Marquis, rue de La-Bataille-Flandres-Dunkerque, CS 44229, 35042 Rennes cedex (France)

    2011-12-15

    Purpose. - In case of tumour displacement, image-guided radiotherapy (IGRT) based on the use of cone beam CT (tomographie conique) allows replacing the tumour under the accelerator by rigid registration. Anatomical deformations require however re-planning, involving an estimation of the cumulative dose, session after session. This is the objective of this study. Patients and methods. - Two examples of arc-intensity modulated radiotherapy are presented: a case of prostate cancer (total dose = 80 Gy) with tomographie conique (daily prostate registration) and one head and neck cancer (70 Gy). For the head and neck cancer, the patient had a weekly scanner allowing a dose distribution calculation. The cumulative dose was calculated per voxel on the planning CT after deformation of the dose distribution (with trilinear interpolation) following the transformation given by a non-rigid registration step (Demons registration method) from: either the tomographie conique (prostate), or the weekly CT. The cumulative dose was eventually compared with the planned dose. Results. - In cases of prostate irradiation, the 'cumulative' dose corresponded to the planned dose to the prostate. At the last week of irradiation, it was above the planned dose for the rectum and bladder. The volume of rectal wall receiving more than 50 Gy (V50) was 20% at the planning and 26% at the end of treatment, increasing the risk of rectal toxicity (NTCP) of 14%. For the bladder wall, V50 were 73% and 82%, respectively. In head and neck, the 'cumulative' dose to the parotid exceeded the planned dose (mean dose increasing from 46 Gy to 54 Gy) from the 5. week of irradiation on, suggesting the need for re-planning within the first 5 weeks of radiotherapy. Conclusion. - The deformable registration estimates the cumulative dose delivered in the different anatomical structures. Validation on digital and physical phantoms is however required before clinical evaluation. (authors)

  10. Retrospective study of cumulative diagnostic radiation exposure during childhood in patients with spina bifida.

    Science.gov (United States)

    Smookler, Gregory; Deavenport-Saman, Alexis

    2015-10-01

    The Biological Effects of Ionizing Radiation Committee of the National Academy of Sciences in 2005 and other expert panels have warned that risk of cancer increases with higher doses of radiation. Children with spina bifida and hydrocephalus have far greater exposure to radiation than the average person, starting almost directly after birth and continuing throughout their lifetimes. The purpose of this study was to estimate the amount of ionizing radiation that patients with spina bifida and hydrocephalus are exposed to during childhood from diagnostic imaging. Thirty patients, ages 18 years or older, with spina bifida and hydrocephalus were randomly selected from a spina bifida clinic and their radiology records were reviewed. Descriptive analyses were conducted. The total radiation exposure was then calculated for the study group, and the mean effective dose per patient was determined. In the study group, during their first 18 years, each patient had a mean of 55.1 studies and a median of 45 radiologic studies, a mean of 9.6 brain CT scans, and a mean cumulative effective dose of 81.9 mSv (2.6 mSv/patient/year over 18 years) and a median cumulative effective dose of 77.2 mSV of accumulated radiation exposure (4.5 mSv/patient/year over 18 years). Clinicians should recognize that increased radiation exposure puts patients with spina bifida and hydrocephalus at higher risk for cancer. The population of children and adults with spina bifida and hydrocephalus should be surveyed for incidence of cancer. Copyright © 2015 Elsevier Inc. All rights reserved.

  11. Cumulative radiation exposure and cancer risk of patients with ischemic heart diseases from diagnostic and therapeutic imaging procedures

    Energy Technology Data Exchange (ETDEWEB)

    Brix, Gunnar, E-mail: gbrix@bfs.de [Department of Medical and Occupational Radiation Protection, Federal Office for Radiation Protection, Ingoldstädter Landstraße 1, D-85764 Oberschleissheim (Germany); Berton, Marc, E-mail: marcberton@web.de [Institute of Clinical Radiology and Nuclear Medicine, University Medical Center Mannheim, University of Heidelberg, Theodor-Kutzer-Ufer 1-3, D-68167 Mannheim (Germany); Nekolla, Elke, E-mail: enekolla@bfs.de [Department of Medical and Occupational Radiation Protection, Federal Office for Radiation Protection, Ingoldstädter Landstraße 1, D-85764 Oberschleissheim (Germany); Lechel, Ursula, E-mail: ulechel@bfs.de [Department of Medical and Occupational Radiation Protection, Federal Office for Radiation Protection, Ingoldstädter Landstraße 1, D-85764 Oberschleissheim (Germany); Schegerer, Alexander, E-mail: aschegerer@bfs.de [Department of Medical and Occupational Radiation Protection, Federal Office for Radiation Protection, Ingoldstädter Landstraße 1, D-85764 Oberschleissheim (Germany); Süselbeck, Tim, E-mail: Tim.Sueselbeck@umm.de [Department of Cardiology, University Medical Center Mannheim, University of Heidelberg, Theodor-Kutzer-Ufer 1-3, D-68167 Mannheim (Germany); Fink, Christian, E-mail: Christian.Fink@umm.de [Institute of Clinical Radiology and Nuclear Medicine, University Medical Center Mannheim, University of Heidelberg, Theodor-Kutzer-Ufer 1-3, D-68167 Mannheim (Germany)

    2013-11-01

    Objectives: To present a detailed analysis of the cumulative radiation exposure and cancer risk of patients with ischemic heart diseases (IHD) from diagnostic and therapeutic imaging. Methods: For 1219 IHD patients, personal and examination data were retrieved from the information systems of a university hospital. For each patient, cumulative organ doses and the corresponding effective dose (E{sup ¯}) resulting from all imaging procedures performed within 3 months before and 12 months after the date of the diagnosis were calculated. The cumulative lifetime attributable risk (LAR{sup ¯}) of the patients to be diseased by radiation-related cancer was estimated using sex-, age-, and organ-specific risk models. Results: Among the 3870 procedures performed in the IHD patients, the most frequent were radiographic examinations (52.4%) followed by coronary catheter angiographies and percutaneous cardiac interventions (41.3%), CT scans (3.9%), and perfusion SPECT (2.3%). 87% of patient exposure resulted from heart catheter procedures. E{sup ¯} and LAR{sup ¯} were significantly higher in males than females (average, 13.3 vs. 10.3 mSv and 0.09 vs. 0.07%, respectively). Contrary to the effective dose, the cancer risk decreased markedly for both sexes with increasing age. Conclusions: Although IHD patients were partially exposed to considerable amounts of radiation, estimated LAR{sup ¯}s were small as compared to their baseline risk to develop cancer in the remaining life.

  12. Cumulative risks of foster care placement for Danish children.

    Science.gov (United States)

    Fallesen, Peter; Emanuel, Natalia; Wildeman, Christopher

    2014-01-01

    Although recent research suggests that the cumulative risk of foster care placement is far higher for American children than originally suspected, little is known about the cumulative risk of foster care placement in other countries, which makes it difficult to gauge the degree to which factor foster care placement is salient in other contexts. In this article, we provide companion estimates to those provided in recent work on the US by using Danish registry data and synthetic cohort life tables to show how high and unequally distributed the cumulative risk of foster care placement is for Danish children. Results suggest that at the beginning of the study period (in 1998) the cumulative risk of foster care placement for Danish children was roughly in line with the risk for American children. Yet, by the end of the study period (2010), the risk had declined to half the risk for American children. Our results also show some variations by parental ethnicity and sex, but these differences are small. Indeed, they appear quite muted relative to racial/ethnic differences in these risks in the United States. Last, though cumulative risks are similar between Danish and American children (especially at the beginning of the study period), the age-specific risk profiles are markedly different, with higher risks for older Danish children than for older American children.

  13. Latino Mothers' Cumulative Food Insecurity Exposure and Child Body Composition.

    Science.gov (United States)

    Hernandez, Daphne C

    2016-01-01

    To document whether an intergenerational transmission of food insecurity is occurring by assessing low-income foreign-born Latino mothers' experiences with food insecurity as none, once (either childhood or adulthood) or twice (during both childhood and adulthood). Also the association between maternal cumulative food insecurity and children's body composition was examined. Maternal self-reported surveys on retrospective measures of food insecurity during childhood, current measures of food insecurity, and demographics were collected from Houston-area community centers (N = 96). Children's body mass index (BMI) and waist circumference (WC) were directly assessed. Covariate-adjusted logistic regression models analyzed the association between cumulative food insecurity experiences and children's body composition. Fifty-eight percent of mothers experienced food insecurity both as a child and as an adult and 31% of the mothers experienced food insecurity either as a child or adult. Maternal cumulative exposure to food insecurity was unrelated to BMI but was negatively related to elevated WC. Although an intergenerational transmission of food insecurity does exist, maternal cumulative exposure to food insecurity does not impact children's body composition negatively in the short term. Studying the long-term effects of cumulative food insecurity exposure can provide information for the development and timing of obesity interventions.

  14. USING CUMULATIVE NUMBER DENSITIES TO COMPARE GALAXIES ACROSS COSMIC TIME

    Energy Technology Data Exchange (ETDEWEB)

    Behroozi, Peter S.; Wechsler, Risa H. [Kavli Institute for Particle Astrophysics and Cosmology, SLAC National Accelerator Laboratory, Stanford, CA 94305 (United States); Marchesini, Danilo [Department of Physics and Astronomy, Tufts University, Medford, MA 02155 (United States); Muzzin, Adam [Leiden Observatory, Leiden University, P.O. Box 9513, 2300 RA Leiden (Netherlands); Papovich, Casey [Department of Physics and Astronomy, Texas A and M University, College Station, TX 77843 (United States); Stefanon, Mauro [Physics and Astronomy Department, University of Missouri, Columbia, MO 65211 (United States)

    2013-11-01

    Comparing galaxies across redshifts at fixed cumulative number density is a popular way to estimate the evolution of specific galaxy populations. This method ignores scatter in mass accretion histories and galaxy-galaxy mergers, which can lead to errors when comparing galaxies over large redshift ranges (Δz > 1). We use abundance matching in the ΛCDM paradigm to estimate the median change in cumulative number density with redshift and provide a simple fit (+0.16 dex per unit Δz) for progenitors of z = 0 galaxies. We find that galaxy descendants do not evolve in the same way as galaxy progenitors, largely due to scatter in mass accretion histories. We also provide estimates for the 1σ range of cumulative number densities corresponding to galaxy progenitors and descendants. Finally, we discuss some limits on cumulative number density comparisons, which arise due to difficulties measuring physical quantities (e.g., stellar mass) consistently across redshifts. A public tool to calculate cumulative number density evolution for galaxies, as well as approximate halo masses, is available online.

  15. Radiation Dose Risk and Diagnostic Benefit in Imaging Investigations

    CERN Document Server

    Dobrescu, Lidia

    2015-01-01

    The paper presents many facets of medical imaging investigations radiological risks. The total volume of prescribed medical investigations proves a serious lack in monitoring and tracking of the cumulative radiation doses in many health services. Modern radiological investigations equipment is continuously reducing the total dose of radiation due to improved technologies, so a decrease in per caput dose can be noticed, but the increasing number of investigations has determined a net increase of the annual collective dose. High doses of radiation are cumulated from Computed Tomography investigations. An integrated system for radiation safety of the patients investigated by radiological imaging methods, based on smart cards and Public Key Infrastructure allow radiation absorbed dose data storage.

  16. Cumulative Trauma Among Mayas Living in Southeast Florida.

    Science.gov (United States)

    Millender, Eugenia I; Lowe, John

    2016-01-04

    Mayas, having experienced genocide, exile, and severe poverty, are at high risk for the consequences of cumulative trauma that continually resurfaces through current fear of an uncertain future. Little is known about the mental health and alcohol use status of this population. This correlational study explored t/he relationship of cumulative trauma as it relates to social determinants of health (years in the United States, education, health insurance status, marital status, and employment), psychological health (depression symptoms), and health behaviors (alcohol use) of 102 Guatemalan Mayas living in Southeast Florida. The results of this study indicated that, as specific social determinants of health and cumulative trauma increased, depression symptoms (particularly among women) and the risk for harmful alcohol use (particularly among men) increased. Identifying risk factors at an early stage before serious disease or problems are manifest provides room for early screening leading to early identification, early treatment, and better outcomes.

  17. Analysis of sensory ratings data with cumulative link models

    DEFF Research Database (Denmark)

    Christensen, Rune Haubo Bojesen; Brockhoff, Per B.

    2013-01-01

    Examples of categorical rating scales include discrete preference, liking and hedonic rating scales. Data obtained on these scales are often analyzed with normal linear regression methods or with omnibus Pearson chi2 tests. In this paper we propose to use cumulative link models that allow...... for regression methods similar to linear models while respecting the categorical nature of the observations. We describe how cumulative link models are related to the omnibus chi2 tests and how they can lead to more powerful tests in the non-replicated setting. For replicated categorical ratings data we present...... a quasi-likelihood approach and a mixed effects approach both being extensions of cumulative link models. We contrast population-average and subject-specific interpretations based on these models and discuss how different approaches lead to different tests. In replicated settings, naive tests that ignore...

  18. Cumulative pion production via successive collisions in nuclear medium

    CERN Document Server

    Motornenko, A

    2016-01-01

    Production of pions in proton-nucleus (p+A) reactions outside of a kinematical boundary of proton-nucleon collisions, the so-called cumulative effect, is studied. The kinematical restrictions on pions emitted in backward direction in the target rest frame are analyzed. It is shown that cumulative pion production requires a presence of massive baryonic resonances that are produced during successive collisions of projectile with nuclear nucleons. After each successive collision the mass of created resonance may increase and, simultaneously, its longitudinal velocity decreases. Simulations within Ultra relativistic Quantum Molecular Dynamics model reveals that successive collisions of baryonic resonances with nuclear nucleons plays the dominant role in cumulative pion production in p+A reactions.

  19. Solid-state electro-cumulation effect numerical simulation

    CERN Document Server

    Grishin, V G

    2001-01-01

    It is an attempt to simulate as really as possible a crystal's interatomic interaction under conditions of "Solid-state electro-cumulation (super-polarization) effect". Some theoretical and experimental reasons to believe that within solid substances an interparticles interaction could concentrate from the surface to a centre were given formerly. Now, numerical results show the conditions that could make the cumulation more effective. Another keywords: ion, current, solid, symmetry, cumulation, polarization, depolarization, ionic conductor,superionic conductor, ice, crystal, strain, V-center, V-centre, doped crystal, interstitial impurity, intrinsic color center, high pressure technology, Bridgman, anvil, experiment, crowdion, dielectric, proton, layer, defect, lattice, dynamics, electromigration, mobility, muon catalysis, concentration, doping, dopant, conductivity, pycnonuclear reaction, permittivity, dielectric constant, point defects, interstitials, polarizability, imperfection, defect centers, glass, epi...

  20. Association between diastolic blood pressure and cumulative work time

    Directory of Open Access Journals (Sweden)

    Ricardo Cordeiro

    1999-01-01

    Full Text Available Diastolic blood pressure was viewed as a generic indicator of aging, and its association with cumulative work time was studied after controlling for age as a potential confounding factor. The study was conducted among production line workers at a Brazilian tannery in July 1993. The association between diastolic blood pressure and cumulative work time was verified by fitting a second-order linear regression model, where diastolic blood pressure was a function of worker's age and cumulative work time. By fitting the model, one can predict that, in the beginning of working life at the tannery, on average each 1-year period is associated with an increase of about 1.5 mmHg in diastolic blood pressure. The fit obtained highlights one component directly associated with work as part of the rate of pressure increase in the study group. This component is twice as high as that directly associated with age.

  1. Baltic Sea biodiversity status vs. cumulative human pressures

    DEFF Research Database (Denmark)

    Andersen, Jesper H.; Halpern, Benjamin S.; Korpinen, Samuli

    2015-01-01

    Abstract Many studies have tried to explain spatial and temporal variations in biodiversity status of marine areas from a single-issue perspective, such as fishing pressure or coastal pollution, yet most continental seas experience a wide range of human pressures. Cumulative impact assessments have...... been developed to capture the consequences of multiple stressors for biodiversity, but the ability of these assessments to accurately predict biodiversity status has never been tested or ground-truthed. This relationship has similarly been assumed for the Baltic Sea, especially in areas with impaired...... status, but has also never been documented. Here we provide a first tentative indication that cumulative human impacts relate to ecosystem condition, i.e. biodiversity status, in the Baltic Sea. Thus, cumulative impact assessments offer a promising tool for informed marine spatial planning, designation...

  2. Session: What do we know about cumulative or population impacts

    Energy Technology Data Exchange (ETDEWEB)

    Kerlinger, Paul; Manville, Al; Kendall, Bill

    2004-09-01

    This session at the Wind Energy and Birds/Bats workshop consisted of a panel discussion followed by a discussion/question and answer period. The panelists were Paul Kerlinger, Curry and Kerlinger, LLC, Al Manville, U.S. Fish and Wildlife Service, and Bill Kendall, US Geological Service. The panel addressed the potential cumulative impacts of wind turbines on bird and bat populations over time. Panel members gave brief presentations that touched on what is currently known, what laws apply, and the usefulness of population modeling. Topics addressed included which sources of modeling should be included in cumulative impacts, comparison of impacts from different modes of energy generation, as well as what research is still needed regarding cumulative impacts of wind energy development on bird and bat populations.

  3. Cumulant dynamics in a finite population linkage equilibrium theory

    CERN Document Server

    Rattray, M; Rattray, Magnus; Shapiro, Jonathan L.

    1999-01-01

    The evolution of a finite population at linkage equilibrium is described in terms of the dynamics of phenotype distribution cumulants. This provides a powerful method for describing evolutionary transients and we elucidate the relationship between the cumulant dynamics and the diffusion approximation. A separation of time-scales between the first and higher cumulants for low mutation rates is demonstrated in the diffusion limit and provides a significant simplification of the dynamical system. However, the diffusion limit may not be appropriate for strong selection as the standard Fisher-Wright model of genetic drift can break down in this case. Two novel examples of this effect are considered: we shown that the dynamics may depend on the number of loci under strong directional selection and that environmental variance results in a reduced effective population size. We also consider a simple model of a changing environment which cannot be described by a diffusion equation and we derive the optimal mutation ra...

  4. Effect of correlation on cumulants in heavy-ion collisions

    CERN Document Server

    Mishra, D K; Netrakanti, P K

    2015-01-01

    We study the effects of correlation on cumulants and their ratios of net-proton multiplicity distribution which have been measured for central (0-5\\%) Au+Au collisions at Relativistic Heavy Ion Collider (RHIC). This effect has been studied assuming individual proton and anti-proton distributions as Poisson or Negative Binomial Distribution (NBD). In-spite of significantly correlated production due to baryon number, electric charge conservation and kinematical correlations of protons and anti-protons, the measured cumulants of net-proton distribution follow the independent production model. In the present work we demonstrate how the introduction of correlations will affect the cumulants and their ratios for the difference distributions. We have also demonstrated this study using the proton and anti-proton distributions obtained from HIJING event generator.

  5. System Dynamics and Modified Cumulant Neglect Closure Schemes

    DEFF Research Database (Denmark)

    Köylüoglu, H. Ugur; Nielsen, Søren R.K.

    Dealing with multipeaked problems, the goal of the paper is to improve the quality of the approximations for the expectations appearing in the differential equations written for the statistical moments of the state vector, guided by insight in the system dynamics. For systems with polynomial non......-linearities, modifications in the cumulant neglect closure scheme are suggested. The methodology is illustrated using the two wells oscillator. An error analysis is performed to compare the modified and ordinary cumulant neglect closure schemes applied at the second and fourth order levels with the exact results available....

  6. Baltic Sea biodiversity status vs. cumulative human pressures

    DEFF Research Database (Denmark)

    Andersen, Jesper H.; Halpern, Benjamin S.; Korpinen, Samuli

    2015-01-01

    been developed to capture the consequences of multiple stressors for biodiversity, but the ability of these assessments to accurately predict biodiversity status has never been tested or ground-truthed. This relationship has similarly been assumed for the Baltic Sea, especially in areas with impaired...... status, but has also never been documented. Here we provide a first tentative indication that cumulative human impacts relate to ecosystem condition, i.e. biodiversity status, in the Baltic Sea. Thus, cumulative impact assessments offer a promising tool for informed marine spatial planning, designation...

  7. Aspect of cumulative fatigue damage under multiaxial strain cycling.

    Science.gov (United States)

    Zamrik, S. Y.; Tang, P. Y.

    1972-01-01

    The concept of order of loading and its effect on cumulative fatigue damage under multiaxial strain cyclings was investigated. The effect is illustrated through nonlinear relationships between biaxial fatigue damage and cycle-ratio diagrams. Uniaxial theories such as Miner's method, the convergence method, and the double linear damage rule in its special and generalized form, were examined and extended to the biaxial case through the octahedral shear strain theory. The generalized double linear damage rule was found more applicable to biaxial cumulative fatigue damage.

  8. Cumulative Incidence of Cancer After Solid Organ Transplantation

    Science.gov (United States)

    Hall, Erin C.; Pfeiffer, Ruth M.; Segev, Dorry L.; Engels, Eric A.

    2014-01-01

    BACKGROUND Solid organ transplantation recipients have elevated cancer incidence. Estimates of absolute cancer risk after transplantation can inform prevention and screening. METHODS The Transplant Cancer Match Study links the US transplantation registry with 14 state/regional cancer registries. The authors used nonparametric competing risk methods to estimate the cumulative incidence of cancer after transplantation for 2 periods (1987–1999 and 2000–2008). For recipients from 2000 to 2008, the 5-year cumulative incidence, stratified by organ, sex, and age at transplantation, was estimated for 6 preventable or screen-detectable cancers. For comparison, the 5-year cumulative incidence was calculated for the same cancers in the general population at representative ages using Surveillance, Epidemiology, and End Results data. RESULTS Among 164,156 recipients, 8520 incident cancers were identified. The absolute cancer risk was slightly higher for recipients during the period from 2000 to 2008 than during the period from 1987 to 1999 (5-year cumulative incidence: 4.4% vs 4.2%; P =.006); this difference arose from the decreasing risk of competing events (5-year cumulative incidence of death, graft failure, or retransplantation: 26.6% vs 31.9%; P 50 years; range, 0.36%–2.22%). For recipients aged >50 years, the 5-year cumulative incidence was higher for colorectal cancer (range, 0.33%–1.94%) than for the general population at the recommended screening age (aged 50 years: range, 0.25%–0.33%). For recipients aged >50 years, the 5-year cumulative incidence was high for lung cancer among thoracic organ recipients (range, 1.16%–3.87%) and for kidney cancer among kidney recipients (range, 0.53%–0.84%). The 5-year cumulative incidence for prostate cancer and breast cancer was similar or lower in transplantation recipients than at the recommended ages of screening in the general population. CONCLUSIONS Subgroups of transplantation recipients have a high absolute risk

  9. A study of cumulative fatigue damage in AISI 4130 steel

    Science.gov (United States)

    Jeelani, S.; Musial, M.

    1986-01-01

    Experimental data were obtained using AISI 4130 steel under stress ratios of -1 and 0. A study of cumulative fatigue damage using Miner's and Kramer's equations for stress ratios of -1 and 0 for low-high, low-high-mixed, high-low, and high-low-mixed stress sequences has revealed that there is a close agreement between the theoretical and experimental values of fatigue damage and fatigue life. Kramer's equation predicts less conservative and more realistic cumulative fatigue damage than the popularly used Miner's rule does.

  10. Residual, direct and cumulative effect of zinc application on wheat and rice yield under rice-wheat syst

    Directory of Open Access Journals (Sweden)

    R. Khan

    2009-05-01

    Full Text Available Zinc (Zn deficiency is prevalent particularly on calcareous soils of arid and semiarid region. A field experiment was conducted to investigate the direct, residual and cumulative effect of zinc on the yield of wheat and rice in permanent layout for two consecutive years, 2004-05 and 2005-06 at Arid Zone Research Institute D.I. Khan. Soil under study was deficient in Zn (0.8 mg kg-1. Effect of Zn on yield, Zn concentrations in leaf and soils were assessed using wheat variety Naseer-2000 and rice variety IRRI-6. Three rates of Zn, ranging from 0 to 10 kg ha-1 in soil, were applied as zinc sulphate (ZnSO4. 7H2O along with basal dose fertilization of nitrogen, phosphorus and potassium. Mature leaf and soil samples were collected at panicle initiation stage. The results showed that grain yield of wheat and rice was significantly increased by the direct application of 5 and 10 kg Zn ha-1. Highest grain yield of wheat (5467 kg ha-1 was recorded with the direct application of 10 kg Zn ha-1 while 4994 kg ha-1 was recorded with the cumulative application of 10 kg Zn ha-1 but the yield increase due to residual effect of Zn was statistically lower than the cumulative effect of Zn. Maximum paddy yield was recorded with the cumulative application ofZn followed by residual and direct applied 10 and 5 kg Zn kg ha-1, respectively. Zn concentration in soils ranged from 0.3 to 1.5 mg kg-1 in wheat and 0.24 to 2.40 mg kg-1 in rice, while in leaves it ranged from 18-48 mg kg-1 in wheat and 15-52 mg kg-1 in rice. The concentration of Zn in soil and leaves increased due to the treatments in the order; cumulative > residual > direct effect > control (without Zn. The yield attributes like 1000- grain weight, number of spikes, spike length and plant height were increased by the residual, direct and cumulative effect of Zn levels; however, the magnitude of increase was higher in cumulative effect than residual and direct effect of Zn, respectively. Under Zn-deficient soil

  11. A Parametric Cumulative Sum Statistic for Person Fit

    Science.gov (United States)

    Armstrong, Ronald D.; Shi, Min

    2009-01-01

    This article develops a new cumulative sum (CUSUM) statistic to detect aberrant item response behavior. Shifts in behavior are modeled with quadratic functions and a series of likelihood ratio tests are used to detect aberrancy. The new CUSUM statistic is compared against another CUSUM approach as well as traditional person-fit statistics. A…

  12. RECURSIVE CLASSIFICATION OF MQAM SIGNALS BASED ON HIGHER ORDER CUMULANTS

    Institute of Scientific and Technical Information of China (English)

    Chen Weidong; Yang Shaoquan

    2002-01-01

    A new feature based on higher order cumulants is proposed for classification of MQAM signals. Theoretical analysis justify that the new feature is invariant with respect to translation (shift), scale and rotation transform of signal constellations, and can suppress color or white additive Gaussian noise. Computer simulation shows that the proposed recursive orderreduction based classification algorithm can classify MQAM signals with any order.

  13. Hierarchical Bayesian parameter estimation for cumulative prospect theory

    NARCIS (Netherlands)

    Nilsson, H.; Rieskamp, J.; Wagenmakers, E.-J.

    2011-01-01

    Cumulative prospect theory (CPT Tversky & Kahneman, 1992) has provided one of the most influential accounts of how people make decisions under risk. CPT is a formal model with parameters that quantify psychological processes such as loss aversion, subjective values of gains and losses, and

  14. Cumulative psychosocial stress, coping resources, and preterm birth.

    Science.gov (United States)

    McDonald, Sheila W; Kingston, Dawn; Bayrampour, Hamideh; Dolan, Siobhan M; Tough, Suzanne C

    2014-12-01

    Preterm birth constitutes a significant international public health issue, with implications for child and family well-being. High levels of psychosocial stress and negative affect before and during pregnancy are contributing factors to shortened gestation and preterm birth. We developed a cumulative psychosocial stress variable and examined its association with early delivery controlling for known preterm birth risk factors and confounding environmental variables. We further examined this association among subgroups of women with different levels of coping resources. Utilizing the All Our Babies (AOB) study, an ongoing prospective pregnancy cohort study in Alberta, Canada (n = 3,021), multinomial logistic regression was adopted to examine the independent effect of cumulative psychosocial stress and preterm birth subgroups compared to term births. Stratified analyses according to categories of perceived social support and optimism were undertaken to examine differential effects among subgroups of women. Cumulative psychosocial stress was a statistically significant risk factor for late preterm birth (OR = 1.73; 95 % CI = 1.07, 2.81), but not for early preterm birth (OR = 2.44; 95 % CI = 0.95, 6.32), controlling for income, history of preterm birth, pregnancy complications, reproductive history, and smoking in pregnancy. Stratified analyses showed that cumulative psychosocial stress was a significant risk factor for preterm birth at psychosocial stress on the risk for early delivery.

  15. The proportional odds cumulative incidence model for competing risks

    DEFF Research Database (Denmark)

    Eriksson, Frank; Li, Jianing; Scheike, Thomas

    2015-01-01

    We suggest an estimator for the proportional odds cumulative incidence model for competing risks data. The key advantage of this model is that the regression parameters have the simple and useful odds ratio interpretation. The model has been considered by many authors, but it is rarely used in pr...

  16. Is learning in problem-based learning cumulative?

    NARCIS (Netherlands)

    E.H.J. Yew (Elaine); E. Chng (Esther); H.G. Schmidt (Henk)

    2011-01-01

    textabstractProblem-based learning (PBL) is generally organized in three phases, involving collaborative and self-directed learning processes. The hypothesis tested here is whether learning in the different phases of PBL is cumulative, with learning in each phase depending on that of the previous ph

  17. Cumulative assessment : Strategic choices to influence students' study effort

    NARCIS (Netherlands)

    Kerdijk, Wouter; Tio, Rene A.; Mulder, B. Florentine; Cohen-Schotanus, Janke

    2013-01-01

    Background: It has been asserted that assessment can and should be used to drive students' learning. In the current study, we present a cumulative assessment program in which test planning, repeated testing and compensation are combined in order to influence study effort. The program is aimed at hel

  18. Repeated mild injury causes cumulative damage to hippocampal cells

    NARCIS (Netherlands)

    E.J. Matser (Amy); C.I. de Zeeuw (Chris); J.T. Weber (John)

    2002-01-01

    textabstractAn interesting hypothesis in the study of neurotrauma is that repeated traumatic brain injury may result in cumulative damage to cells of the brain. However, post-injury sequelae are difficult to address at the cellular level in vivo. Therefore, it is necessary to compl

  19. The effects of cumulative practice on mathematics problem solving.

    Science.gov (United States)

    Mayfield, Kristin H; Chase, Philip N

    2002-01-01

    This study compared three different methods of teaching five basic algebra rules to college students. All methods used the same procedures to teach the rules and included four 50-question review sessions interspersed among the training of the individual rules. The differences among methods involved the kinds of practice provided during the four review sessions. Participants who received cumulative practice answered 50 questions covering a mix of the rules learned prior to each review session. Participants who received a simple review answered 50 questions on one previously trained rule. Participants who received extra practice answered 50 extra questions on the rule they had just learned. Tests administered after each review included new questions for applying each rule (application items) and problems that required novel combinations of the rules (problem-solving items). On the final test, the cumulative group outscored the other groups on application and problem-solving items. In addition, the cumulative group solved the problem-solving items significantly faster than the other groups. These results suggest that cumulative practice of component skills is an effective method of training problem solving.

  20. A Parametric Cumulative Sum Statistic for Person Fit

    Science.gov (United States)

    Armstrong, Ronald D.; Shi, Min

    2009-01-01

    This article develops a new cumulative sum (CUSUM) statistic to detect aberrant item response behavior. Shifts in behavior are modeled with quadratic functions and a series of likelihood ratio tests are used to detect aberrancy. The new CUSUM statistic is compared against another CUSUM approach as well as traditional person-fit statistics. A…

  1. Variable cultural acquisition costs constrain cumulative cultural evolution.

    Directory of Open Access Journals (Sweden)

    Alex Mesoudi

    Full Text Available One of the hallmarks of the human species is our capacity for cumulative culture, in which beneficial knowledge and technology is accumulated over successive generations. Yet previous analyses of cumulative cultural change have failed to consider the possibility that as cultural complexity accumulates, it becomes increasingly costly for each new generation to acquire from the previous generation. In principle this may result in an upper limit on the cultural complexity that can be accumulated, at which point accumulated knowledge is so costly and time-consuming to acquire that further innovation is not possible. In this paper I first review existing empirical analyses of the history of science and technology that support the possibility that cultural acquisition costs may constrain cumulative cultural evolution. I then present macroscopic and individual-based models of cumulative cultural evolution that explore the consequences of this assumption of variable cultural acquisition costs, showing that making acquisition costs vary with cultural complexity causes the latter to reach an upper limit above which no further innovation can occur. These models further explore the consequences of different cultural transmission rules (directly biased, indirectly biased and unbiased transmission, population size, and cultural innovations that themselves reduce innovation or acquisition costs.

  2. Cumulative index 1981-1985, Volumes 138-157.

    Science.gov (United States)

    1985-01-01

    This cumulative index also includes listings of all major papers from the American Journal of Neuroradiology, American Journal of Roentgenology, Clinics in Diagnostic Ultrasound, Journal of Computer Assisted Tomography, Journal of Ultrasound in Medicine, RadioGraphics, Radiologic Clinics of North America, Seminars in Nuclear Medicine, Seminars in Roentgenology, and Seminars in Ultrasound, CT and MR.

  3. Cumulative index 1981-1985, Volumes 138-157

    Energy Technology Data Exchange (ETDEWEB)

    1985-01-01

    This cumulative index also includes listings of all major papers from the American Journal of Neuroradiology, American Journal of Roentgenology, Clinics in Diagnostic Ultrasound, Journal of Computer Assisted Tomography, Journal of Ultrasound in Medicine, RadioGraphics, Radiologic Clinics of North America, Seminars in Nuclear Medicine, Seminars in Roentgenology, and Seminars in Ultrasound, CT and MR.

  4. The role of cumulative physical work load in symptomatic knee osteoarthritis – a case-control study in Germany

    Directory of Open Access Journals (Sweden)

    Abolmaali Nasreddin

    2008-07-01

    Full Text Available Abstract Objectives To examine the dose-response relationship between cumulative exposure to kneeling and squatting as well as to lifting and carrying of loads and symptomatic knee osteoarthritis (OA in a population-based case-control study. Methods In five orthopedic clinics and five practices we recruited 295 male patients aged 25 to 70 with radiographically confirmed knee osteoarthritis associated with chronic complaints. A total of 327 male control subjects were recruited. Data were gathered in a structured personal interview. To calculate cumulative exposure, the self-reported duration of kneeling and squatting as well as the duration of lifting and carrying of loads were summed up over the entire working life. Results The results of our study support a dose-response relationship between kneeling/squatting and symptomatic knee osteoarthritis. For a cumulative exposure to kneeling and squatting > 10.800 hours, the risk of having radiographically confirmed knee osteoarthritis as measured by the odds ratio (adjusted for age, region, weight, jogging/athletics, and lifting or carrying of loads is 2.4 (95% CI 1.1–5.0 compared to unexposed subjects. Lifting and carrying of loads is significantly associated with knee osteoarthritis independent of kneeling or similar activities. Conclusion As the knee osteoarthritis risk is strongly elevated in occupations that involve both kneeling/squatting and heavy lifting/carrying, preventive efforts should particularly focus on these "high-risk occupations".

  5. Multiple anatomy optimization of accumulated dose

    Energy Technology Data Exchange (ETDEWEB)

    Watkins, W. Tyler, E-mail: watkinswt@virginia.edu; Siebers, Jeffrey V. [Department of Radiation Oncology, University of Virginia, Charlottesville, Virginia 22908 and Department of Radiation Oncology, Virginia Commonwealth University, Richmond, Virginia 23298 (United States); Moore, Joseph A. [Department of Radiation Oncology and Molecular Radiation Sciences, Johns Hopkins University, Baltimore, Maryland 21231 and Department of Radiation Oncology, Virginia Commonwealth University, Richmond, Virginia 23298 (United States); Gordon, James [Henry Ford Health System, Detroit, Michigan 48202 and Department of Radiation Oncology, Virginia Commonwealth University, Richmond, Virginia 23298 (United States); Hugo, Geoffrey D. [Department of Radiation Oncology, Virginia Commonwealth University, Richmond, Virginia 23298 (United States)

    2014-11-01

    Purpose: To investigate the potential advantages of multiple anatomy optimization (MAO) for lung cancer radiation therapy compared to the internal target volume (ITV) approach. Methods: MAO aims to optimize a single fluence to be delivered under free-breathing conditions such that the accumulated dose meets the plan objectives, where accumulated dose is defined as the sum of deformably mapped doses computed on each phase of a single four dimensional computed tomography (4DCT) dataset. Phantom and patient simulation studies were carried out to investigate potential advantages of MAO compared to ITV planning. Through simulated delivery of the ITV- and MAO-plans, target dose variations were also investigated. Results: By optimizing the accumulated dose, MAO shows the potential to ensure dose to the moving target meets plan objectives while simultaneously reducing dose to organs at risk (OARs) compared with ITV planning. While consistently superior to the ITV approach, MAO resulted in equivalent OAR dosimetry at planning objective dose levels to within 2% volume in 14/30 plans and to within 3% volume in 19/30 plans for each lung V20, esophagus V25, and heart V30. Despite large variations in per-fraction respiratory phase weights in simulated deliveries at high dose rates (e.g., treating 4/10 phases during single fraction beams) the cumulative clinical target volume (CTV) dose after 30 fractions and per-fraction dose were constant independent of planning technique. In one case considered, however, per-phase CTV dose varied from 74% to 117% of prescription implying the level of ITV-dose heterogeneity may not be appropriate with conventional, free-breathing delivery. Conclusions: MAO incorporates 4DCT information in an optimized dose distribution and can achieve a superior plan in terms of accumulated dose to the moving target and OAR sparing compared to ITV-plans. An appropriate level of dose heterogeneity in MAO plans must be further investigated.

  6. CUMULANTS OF STOCHASTIC RESPONSE FOR A CLASS OF SPECIAL NONHOLONOMIC SYSTEMS

    Institute of Scientific and Technical Information of China (English)

    SHANG MEI; ZHANG YI

    2001-01-01

    This paper studies the response cumulants for a kind of special nonholonomic systems under non-Gaussian, delta- correlated excitations. We present a new methodology for formulating the equations governing the evolution of the response cumulants of the stochastic dynamic systems. The response cumulant differential equations (CDEs) derived can be used to calculate the response cumulants for both linear and nonlinear systems. One example is given to illustrate how to use the CDEs for calculating response cumulants.

  7. Computed tomography dose optimisation in cystic fibrosis: A review.

    LENUS (Irish Health Repository)

    Ferris, Helena

    2016-04-28

    Cystic fibrosis (CF) is the most common autosomal recessive disease of the Caucasian population worldwide, with respiratory disease remaining the most relevant source of morbidity and mortality. Computed tomography (CT) is frequently used for monitoring disease complications and progression. Over the last fifteen years there has been a six-fold increase in the use of CT, which has lead to a growing concern in relation to cumulative radiation exposure. The challenge to the medical profession is to identify dose reduction strategies that meet acceptable image quality, but fulfil the requirements of a diagnostic quality CT. Dose-optimisation, particularly in CT, is essential as it reduces the chances of patients receiving cumulative radiation doses in excess of 100 mSv, a dose deemed significant by the United Nations Scientific Committee on the Effects of Atomic Radiation. This review article explores the current trends in imaging in CF with particular emphasis on new developments in dose optimisation.

  8. Cloud mask via cumulative discriminant analysis applied to satellite infrared observations: scientific basis and initial evaluation

    Directory of Open Access Journals (Sweden)

    U. Amato

    2014-06-01

    Full Text Available We introduce a classification method (Cumulative Discriminant Analysis of the Discriminant Analysis type to discriminate between cloudy and clear sky satellite observations in the thermal infrared. The tool is intended for the high spectral resolution infrared sounder (IRS planned for the geostationary METEOSAT (Meteorological Satellite Third Generation platform and uses IASI (Infrared Atmospheric Sounding Interferometer data as a proxy. The Cumulative Discriminant Analysis does not introduce biases intrinsic with the approximation of the probability density functions and is flexible enough to adapt to different strategies to optimize the cloud mask. The methodology is based on nine statistics computed from IASI spectral radiances, which exploit the high spectral resolution of the instrument and which effectively summarize information contained within the IASI spectrum. A Principal Component Analysis prior step is also introduced which makes the problem more consistent with the statistical assumptions of the methodology. An initial assessment of the scheme is performed based on global and regional IASI real data sets and cloud masks obtained from AVHRR (Advanced Very High Resolution Radiometer and SEVIRI (Spinning Enhanced Visible and Infrared Imager imagers. The agreement with these independent cloud masks is generally well above 80%, except at high latitudes in their winter seasons.

  9. Cloud mask via cumulative discriminant analysis applied to satellite infrared observations: scientific basis and initial evaluation

    Science.gov (United States)

    Amato, U.; Lavanant, L.; Liuzzi, G.; Masiello, G.; Serio, C.; Stuhlmann, R.; Tjemkes, S. A.

    2014-10-01

    We introduce a classification method (cumulative discriminant analysis) of the discriminant analysis type to discriminate between cloudy and clear-sky satellite observations in the thermal infrared. The tool is intended for the high-spectral-resolution infrared sounder (IRS) planned for the geostationary METEOSAT (Meteorological Satellite) Third Generation platform and uses IASI (Infrared Atmospheric Sounding Interferometer) data as a proxy. The cumulative discriminant analysis does not introduce biases intrinsic with the approximation of the probability density functions and is flexible enough to adapt to different strategies to optimize the cloud mask. The methodology is based on nine statistics computed from IASI spectral radiances, which exploit the high spectral resolution of the instrument and which effectively summarize information contained within the IASI spectrum. A principal component analysis prior step is also introduced, which makes the problem more consistent with the statistical assumptions of the methodology. An initial assessment of the scheme is performed based on global and regional IASI real data sets and cloud masks obtained from AVHRR (Advanced Very High Resolution Radiometer) and SEVIRI (Spinning Enhanced Visible and Infrared Imager) imagers. The agreement with these independent cloud masks is generally well above 80 %, except at high latitudes in the winter seasons.

  10. Optimization of the cumulative risk assessment of pesticides and biocides using computational techniques: Pilot project

    DEFF Research Database (Denmark)

    Jonsdottir, Svava Osk; Reffstrup, Trine Klein; Petersen, Annette

    This pilot project is intended as the first step in developing a computational strategy to assist in refining methods for higher tier cumulative and aggregate risk assessment of exposure to mixture of pesticides and biocides. For this purpose, physiologically based toxicokinetic (PBTK) models were...... developed for two compounds, tebuconazole and prochloraz, and a binary mixture of these compounds in two species, rat and human. PBTK models can be used to estimate the concentration levels (internal doses) of toxic substances and their metabolites in blood and tissue, by a collection of differential...... the models. Exposure scenarios were constructed based on findings of pesticide residues in food of ordinary consumers, and assessment of dermal exposure of professional workers. PBTK simulations were carried using these scenarios....

  11. Non-chemical stressors and cumulative risk assessment: an overview of current initiatives and potential air pollutant interactions.

    Science.gov (United States)

    Lewis, Ari S; Sax, Sonja N; Wason, Susan C; Campleman, Sharan L

    2011-06-01

    Regulatory agencies are under increased pressure to consider broader public health concerns that extend to multiple pollutant exposures, multiple exposure pathways, and vulnerable populations. Specifically, cumulative risk assessment initiatives have stressed the importance of considering both chemical and non-chemical stressors, such as socioeconomic status (SES) and related psychosocial stress, in evaluating health risks. The integration of non-chemical stressors into a cumulative risk assessment framework has been largely driven by evidence of health disparities across different segments of society that may also bear a disproportionate risk from chemical exposures. This review will discuss current efforts to advance the field of cumulative risk assessment, highlighting some of the major challenges, discussed within the construct of the traditional risk assessment paradigm. Additionally, we present a summary of studies of potential interactions between social stressors and air pollutants on health as an example of current research that supports the incorporation of non-chemical stressors into risk assessment. The results from these studies, while suggestive of possible interactions, are mixed and hindered by inconsistent application of social stress indicators. Overall, while there have been significant advances, further developments across all of the risk assessment stages (i.e., hazard identification, exposure assessment, dose-response, and risk characterization) are necessary to provide a scientific basis for regulatory actions and effective community interventions, particularly when considering non-chemical stressors. A better understanding of the biological underpinnings of social stress on disease and implications for chemical-based dose-response relationships is needed. Furthermore, when considering non-chemical stressors, an appropriate metric, or series of metrics, for risk characterization is also needed. Cumulative risk assessment research will benefit

  12. A cumulative entropy method for distribution recognition of model error

    Science.gov (United States)

    Liang, Yingjie; Chen, Wen

    2015-02-01

    This paper develops a cumulative entropy method (CEM) to recognize the most suitable distribution for model error. In terms of the CEM, the Lévy stable distribution is employed to capture the statistical properties of model error. The strategies are tested on 250 experiments of axially loaded CFT steel stub columns in conjunction with the four national building codes of Japan (AIJ, 1997), China (DL/T, 1999), the Eurocode 4 (EU4, 2004), and United States (AISC, 2005). The cumulative entropy method is validated as more computationally efficient than the Shannon entropy method. Compared with the Kolmogorov-Smirnov test and root mean square deviation, the CEM provides alternative and powerful model selection criterion to recognize the most suitable distribution for the model error.

  13. Experience of cumulative effects assessment in the UK

    Directory of Open Access Journals (Sweden)

    Piper Jake

    2004-01-01

    Full Text Available Cumulative effects assessment (CEA is a development of environmental impact assessment which attempts to take into account the wider picture of what impacts may affect the environment as a result of either multiple or linear projects, or development plans. CEA is seen as a further valuable tool in promoting sustainable development. The broader canvas upon which the assessment is made leads to a suite of issues such as complexity in methods and assessment of significance, the desirability of co-operation between developers and other parties, new ways of addressing mitigation and monitoring. After outlining the legislative position and the process of CEA, this paper looks at three cases studies in the UK where cumulative assessment has been carried out - the cases concern wind farms, major infrastructure and off-shore developments.

  14. Petrogenesis of the nakhlite meteorites - Evidence from cumulate mineral zoning

    Science.gov (United States)

    Harvey, Ralph P.; Mcsween, Harry Y., Jr.

    1992-01-01

    Attention is given to a simple igneous petrogenesis for the meteorite Nakhla, which was previously called into question because Mg/Fe ratios in olivine indicate substantial disequilibrium between the predominant cumulus minerals (olivine and augite). Comparative analyses of simulated diffusive zoning and the observed cumulus mineral zoning for all three nakhlites (Nakhla, Governador Valadares, and Lafayette) show that their current compositions do not necessarily reflect parental magma compositions. Diffusion has altered primary cumulus compositions to varying degrees, Nakhla being the least affected, and Lafayette being almost completely reequilibrated. Since mineral zoning in each meteorite is strongly concentric around mesostasis areas, it is inferred that reaction with intercumulus liquid has controlled the observed zoning. It is argued that the nakhlites appear to be a series of relatively simple cumulate rocks which have undergone various amounts of late-magmatic and subsolidus diffusion, possibly reflecting their relative positions in a cooling cumulate pile.

  15. Cumulative dietary exposure of the population of Denmark to pesticides

    DEFF Research Database (Denmark)

    Jensen, Bodil Hamborg; Petersen, Annette; Nielsen, Elsa

    2015-01-01

    We used the Hazard Index (HI) method to carry out a cumulative risk assessment after chronic dietary exposure to all monitored pesticides in fruit, vegetables and cereals for various consumer groups in Denmark. Residue data for all the pesticides were obtained from the Danish monitoring programme...... that included processing factors and set non-detects to ½ LOR, but limited the correction (Model 3), gave the most realistic exposure estimate. With Model 3 the HI was calculated to be 0.44 for children and 0.18 for adults, indicating that there is no risk of adverse health effects following chronic cumulative...... exposure to the pesticides found in fruit, vegetables and cereals on the Danish market. The HI was below 1 even for consumers who eat more than 550 g of fruit and vegetables per day, corresponding to 1/3 of the population. Choosing Danish-produced commodities whenever possible could reduce the HI...

  16. Cumulative impacts of oil fields on northern alaskan landscapes.

    Science.gov (United States)

    Walker, D A; Webber, P J; Binnian, E F; Everett, K R; Lederer, N D; Nordstrand, E A; Walker, M D

    1987-11-06

    Proposed further developments on Alaska's Arctic Coastal Plain raise questions about cumulative effects on arctic tundra ecosystems of development of multiple large oil fields. Maps of historical changes to the Prudhoe Bay Oil Field show indirect impacts can lag behind planned developments by many years and the total area eventually disturbed can greatly exceed the planned area of construction. For example, in the wettest parts of the oil field (flat thaw-lake plains), flooding and thermokarst covered more than twice the area directly affected by roads and other construction activities. Protecting critical wildlife habitat is the central issue for cumulative impact analysis in northern Alaska. Comprehensive landscape planning with the use of geographic information system technology and detailed geobotanical maps can help identify and protect areas of high wildlife use.

  17. Effective Carrier Sensing in CSMA Networks under Cumulative Interference

    CERN Document Server

    Fu, Liqun; Huang, Jianwei

    2009-01-01

    This paper proposes and investigates the concept of a safe carrier-sensing range that can guarantee interference safe (also termed hidden-node-free) transmissions in CSMA networks under the cumulative interference model. Compared with the safe carrier-sensing range under the commonly assumed but less realistic pairwise interference model, we show that the safe carrier-sensing range required under the cumulative interference model is larger by a constant multiplicative factor. The concept of a safe carrier-sensing range, although amenable to elegant analytical results, is inherently not compatible with the conventional power threshold carrier-sensing mechanism (e.g., that used in IEEE 802.11). Specifically, the absolute power sensed by a node in the conventional mechanism does not contain enough information for it to derive its distances from other concurrent transmitter nodes. We show that, fortunately, a carrier-sensing mechanism called Incremental-Power Carrier-Sensing (IPCS) can realize the carrier-sensing...

  18. Cumulants and Correlation Functions vs the QCD phase diagram

    CERN Document Server

    Bzdak, Adam; Strodthoff, Nils

    2016-01-01

    In this note we discuss the relation of particle number cumulants and correlation functions related to them. It is argued that measuring couplings of the genuine correlation functions could provide cleaner information on possible non-trivial dynamics in heavy-ion collisions. We extract integrated multi-particle correlation functions from the presently available experimental data on proton cumulants. We find that the STAR data contain significant four-particle correlations, at least at the lower energies, with indication of changing dynamics in central collisions. We also find that these correlations are rather long-ranged in rapidity. Finally based on the signs of genuine correlation functions we provide exclusion plots for the QCD phase diagram.

  19. Seasonal climate change patterns due to cumulative CO2 emissions

    Science.gov (United States)

    Partanen, Antti-Ilari; Leduc, Martin; Damon Matthews, H.

    2017-07-01

    Cumulative CO2 emissions are near linearly related to both global and regional changes in annual-mean surface temperature. These relationships are known as the transient climate response to cumulative CO2 emissions (TCRE) and the regional TCRE (RTCRE), and have been shown to remain approximately constant over a wide range of cumulative emissions. Here, we assessed how well this relationship holds for seasonal patterns of temperature change, as well as for annual-mean and seasonal precipitation patterns. We analyzed an idealized scenario with CO2 concentration growing at an annual rate of 1% using data from 12 Earth system models from the Coupled Model Intercomparison Project Phase 5 (CMIP5). Seasonal RTCRE values for temperature varied considerably, with the highest seasonal variation evident in the Arctic, where RTCRE was about 5.5 °C per Tt C for boreal winter and about 2.0 °C per Tt C for boreal summer. Also the precipitation response in the Arctic during boreal winter was stronger than during other seasons. We found that emission-normalized seasonal patterns of temperature change were relatively robust with respect to time, though they were sub-linear with respect to emissions particularly near the Arctic. Moreover, RTCRE patterns for precipitation could not be quantified robustly due to the large internal variability of precipitation. Our results suggest that cumulative CO2 emissions are a useful metric to predict regional and seasonal changes in precipitation and temperature. This extension of the TCRE framework to seasonal and regional climate change is helpful for communicating the link between emissions and climate change to policy-makers and the general public, and is well-suited for impact studies that could make use of estimated regional-scale climate changes that are consistent with the carbon budgets associated with global temperature targets.

  20. Heavy metal cumulation in crops after the sewage sludge application

    Directory of Open Access Journals (Sweden)

    Gondová Andrea

    1998-12-01

    Full Text Available During 1995 - 1996 the crops samples after the sewage sludge application were collected. The heavy metals cumulation in investigated crops from Bardejov increased in order: Zn > Cu > Pb > Ni > Cr > Cd and Banská Bystrica : Zn > Cu > Cr > Ni > Pb > Cd. Heavy metals contents after the sewage sludge application were increased in comparison with the highest admissible concentration in eatable part of crops. The sewage sludge application were not recommended in soils for the growth of vegetables

  1. The cumulation of methylmercury in fish (Poecilia reticulata)

    Energy Technology Data Exchange (ETDEWEB)

    Stary, J.; Kratzer, K.; Havlik, B.; Prasilova, J.; Hanusova, J.

    1980-01-01

    Methylmercury labelled with mercury-203 was used for the investigation of the uptake and the release of methylmercury in fish. It has been found that methylmercury compounds adsorbed on fish food remain completely in fish and that they are released with the biological half-time of 110 days. The cumulation of methylmercury from water is very rapid. Equations for the calculation of the concentration of methylmercury in fish were derived and compared with the uptake of phenylmercury and inorganic mercury.

  2. Erupted cumulate fragments in rhyolites from Lipari (Aeolian Islands)

    Science.gov (United States)

    Forni, Francesca; Ellis, Ben S.; Bachmann, Olivier; Lucchi, Federico; Tranne, Claudio A.; Agostini, Samuele; Dallai, Luigi

    2015-12-01

    Over the last ~267 ky, the island of Lipari has erupted magmas ranging in compositions from basaltic andesites to rhyolites, with a notable compositional gap in the dacite field. Bulk geochemical and isotopic compositions of the volcanic succession, in conjunction with major and trace elemental compositions of minerals, indicate that the rhyolites were dominantly generated via crystal fractionation processes, with subordinate assimilation. Radiogenic (Sr, Nd, and Pb) and stable (O) isotopes independently suggest ≤30 % of crustal contamination with the majority of it occurring in mafic compositions, likely relatively deep in the system. Within the rhyolites, crystal-rich, K2O-rich enclaves are common. In contrast to previous interpretations, we suggest that these enclaves represent partial melting, remobilization and eruption of cumulate fragments left-over from rhyolite melt extraction. Cumulate melting and remobilization is supported by the presence of (1) resorbed, low-temperature minerals (biotite and sanidine), providing the potassic signature to these clasts, (2) reacted Fo-rich olivine, marking the presence of mafic recharge, (3) An38-21 plagioclase, filling the gap in feldspar composition between the andesites and the rhyolites and (4) strong enrichment in Sr and Ba in plagioclase and sanidine, suggesting crystallization from a locally enriched melt. Based on Sr-melt partitioning, the high-Sr plagioclase would require ~2300 ppm Sr in the melt, a value far in excess of Sr contents in Lipari and Vulcano magmas (50-1532 ppm) but consistent with melting of a feldspar-rich cumulate. Due to the presence of similar crystal-rich enclaves within the rhyolites from Vulcano, we propose that the eruption of remobilized cumulates associated with high-SiO2 rhyolites may be a common process at the Aeolian volcanoes, as already attested for a variety of volcanic systems around the world.

  3. [Cumulative effect of Coriolis acceleration on coronary hemodynamics].

    Science.gov (United States)

    Lapaev, E V; Bednenko, V S

    1985-01-01

    Time-course variations in coronary circulation and cardiac output were measured in 29 healthy test subjects who performed tests with a continuous cumulation of Coriolis accelerations and in 12 healthy test subjects who were exposed to Coriolis accelerations combined with acute hypoxia. Adaptive changes in coronary circulation were seen. It is recommended to monitor coronary circulation during vestibulometric tests as part of medical expertise of the flying personnel.

  4. Cumulative Risk Assessment Toolbox: Methods and Approaches for the Practitioner

    Directory of Open Access Journals (Sweden)

    Margaret M. MacDonell

    2013-01-01

    Full Text Available The historical approach to assessing health risks of environmental chemicals has been to evaluate them one at a time. In fact, we are exposed every day to a wide variety of chemicals and are increasingly aware of potential health implications. Although considerable progress has been made in the science underlying risk assessments for real-world exposures, implementation has lagged because many practitioners are unaware of methods and tools available to support these analyses. To address this issue, the US Environmental Protection Agency developed a toolbox of cumulative risk resources for contaminated sites, as part of a resource document that was published in 2007. This paper highlights information for nearly 80 resources from the toolbox and provides selected updates, with practical notes for cumulative risk applications. Resources are organized according to the main elements of the assessment process: (1 planning, scoping, and problem formulation; (2 environmental fate and transport; (3 exposure analysis extending to human factors; (4 toxicity analysis; and (5 risk and uncertainty characterization, including presentation of results. In addition to providing online access, plans for the toolbox include addressing nonchemical stressors and applications beyond contaminated sites and further strengthening resource accessibility to support evolving analyses for cumulative risk and sustainable communities.

  5. Finite Volume Cumulant Expansion in QCD-Colorless Plasma

    CERN Document Server

    Ladrem, M; Al-Full, Z; Cherif, S

    2015-01-01

    Due to the finite size effects, the localisation of the phase transition in finite systems and the determination of its order, become an extremely difficult task, even in the simplest known cases. In order to identify and locate the finite volume transition point $T_{0}(V)$ of the QCD deconfinement phase transition to a Colorless QGP, we have developed a new approach using the finite size cumulant expansion of the order parameter and the $L_{mn}$-method. The first six cumulants $C_{1,2,3,4,5,6}$ with the corresponding under-normalized ratios(skewness $\\Sigma$, kurtosis $\\kappa$ ,pentosis $\\Pi_{\\pm}$ and hexosis $\\mathcal{H}_{1,2,3}$) and three unnormalized combinations of them ($\\mathcal{O}={\\mathcal{\\sigma }^{2} \\mathcal{\\kappa } }{\\mathbf{\\Sigma }^{-1} }$, $\\mathcal{U} ={\\mathcal{\\sigma }^{-2} \\mathbf{\\Sigma }^{-1} }$, $\\mathcal{N} = \\mathcal{\\sigma }^{2} \\mathcal{\\kappa }$) are calculated and studied as functions of $(T,V)$. A new approach, unifying in a clear and consistent way the definitions of cumulant...

  6. Cumulative Risk Assessment Toolbox: Methods and Approaches for the Practitioner

    Science.gov (United States)

    MacDonell, Margaret M.; Haroun, Lynne A.; Teuschler, Linda K.; Rice, Glenn E.; Hertzberg, Richard C.; Butler, James P.; Chang, Young-Soo; Clark, Shanna L.; Johns, Alan P.; Perry, Camarie S.; Garcia, Shannon S.; Jacobi, John H.; Scofield, Marcienne A.

    2013-01-01

    The historical approach to assessing health risks of environmental chemicals has been to evaluate them one at a time. In fact, we are exposed every day to a wide variety of chemicals and are increasingly aware of potential health implications. Although considerable progress has been made in the science underlying risk assessments for real-world exposures, implementation has lagged because many practitioners are unaware of methods and tools available to support these analyses. To address this issue, the US Environmental Protection Agency developed a toolbox of cumulative risk resources for contaminated sites, as part of a resource document that was published in 2007. This paper highlights information for nearly 80 resources from the toolbox and provides selected updates, with practical notes for cumulative risk applications. Resources are organized according to the main elements of the assessment process: (1) planning, scoping, and problem formulation; (2) environmental fate and transport; (3) exposure analysis extending to human factors; (4) toxicity analysis; and (5) risk and uncertainty characterization, including presentation of results. In addition to providing online access, plans for the toolbox include addressing nonchemical stressors and applications beyond contaminated sites and further strengthening resource accessibility to support evolving analyses for cumulative risk and sustainable communities. PMID:23762048

  7. 4D Near-Field Source Localization Using Cumulant

    Directory of Open Access Journals (Sweden)

    Zhao Feng

    2007-01-01

    Full Text Available This paper proposes a new cumulant-based algorithm to jointly estimate four-dimensional (4D source parameters of multiple near-field narrowband sources. Firstly, this approach proposes a new cross-array, and constructs five high-dimensional Toeplitz matrices using the fourth-order cumulants of some properly chosen sensor outputs; secondly, it forms a parallel factor (PARAFAC model in the cumulant domain using these matrices, and analyzes the unique low-rank decomposition of this model; thirdly, it jointly estimates the frequency, two-dimensional (2D directions-of-arrival (DOAs, and range of each near-field source from the matrices via the low-rank three-way array (TWA decomposition. In comparison with some available methods, the proposed algorithm, which efficiently makes use of the array aperture, can localize sources using sensors. In addition, it requires neither pairing parameters nor multidimensional search. Simulation results are presented to validate the performance of the proposed method.

  8. 4D Near-Field Source Localization Using Cumulant

    Directory of Open Access Journals (Sweden)

    Junying Zhang

    2007-01-01

    Full Text Available This paper proposes a new cumulant-based algorithm to jointly estimate four-dimensional (4D source parameters of multiple near-field narrowband sources. Firstly, this approach proposes a new cross-array, and constructs five high-dimensional Toeplitz matrices using the fourth-order cumulants of some properly chosen sensor outputs; secondly, it forms a parallel factor (PARAFAC model in the cumulant domain using these matrices, and analyzes the unique low-rank decomposition of this model; thirdly, it jointly estimates the frequency, two-dimensional (2D directions-of-arrival (DOAs, and range of each near-field source from the matrices via the low-rank three-way array (TWA decomposition. In comparison with some available methods, the proposed algorithm, which efficiently makes use of the array aperture, can localize N−3 sources using N sensors. In addition, it requires neither pairing parameters nor multidimensional search. Simulation results are presented to validate the performance of the proposed method.

  9. Childhood poverty and health: cumulative risk exposure and stress dysregulation.

    Science.gov (United States)

    Evans, Gary W; Kim, Pilyoung

    2007-11-01

    A massive literature documents the inverse association between poverty or low socioeconomic status and health, but little is known about the mechanisms underlying this robust relation. We examined longitudinal relations between duration of poverty exposure since birth, cumulative risk exposure, and physiological stress in two hundred seven 13-year-olds. Chronic stress was assessed by basal blood pressure and overnight cortisol levels; stress regulation was assessed by cardiovascular reactivity to a standard acute stressor and recovery after exposure to this stressor. Cumulative risk exposure was measured by multiple physical (e.g., substandard housing) and social (e.g., family turmoil) risk factors. The greater the number of years spent living in poverty, the more elevated was overnight cortisol and the more dysregulated was the cardiovascular response (i.e., muted reactivity). Cardiovascular recovery was not affected by duration of poverty exposure. Unlike the duration of poverty exposure, concurrent poverty (i.e., during adolescence) did not affect these physiological stress outcomes. The effects of childhood poverty on stress dysregulation are largely explained by cumulative risk exposure accompanying childhood poverty.

  10. Multiway Filtering Based on Fourth-Order Cumulants

    Directory of Open Access Journals (Sweden)

    Salah Bourennane

    2005-05-01

    Full Text Available We propose a new multiway filtering based on fourth-order cumulants for the denoising of noisy data tensor with correlated Gaussian noise. The classical multiway filtering is based on the TUCKALS3 algorithm that computes a lower-rank tensor approximation. The presented method relies on the statistics of the analyzed multicomponent signal. We first recall how the well-known lower rank-(K1,…,KN tensor approximation processed by TUCKALS3 alternating least square algorithm exploits second-order statistics. Then, we propose to introduce the fourth-order statistics in the TUCKALS3-based method. Indeed, the use of fourth-order cumulants enables to remove the Gaussian components of an additive noise. In the presented method the estimation of the n-mode projector on the n-mode signal subspace are built from the eigenvectors associated with the largest eigenvalues of a fourth-order cumulant slice matrix instead of a covariance matrix. Each projector is applied by means of the n-mode product operator on the n-mode of the data tensor. The qualitative results of the improved multiway TUCKALS3-based filterings are shown for the case of noise reduction in a color image and multicomponent seismic data.

  11. Cumulative risk hypothesis: Predicting and preventing child maltreatment recidivism.

    Science.gov (United States)

    Solomon, David; Åsberg, Kia; Peer, Samuel; Prince, Gwendolyn

    2016-08-01

    Although Child Protective Services (CPS) and other child welfare agencies aim to prevent further maltreatment in cases of child abuse and neglect, recidivism is common. Having a better understanding of recidivism predictors could aid in preventing additional instances of maltreatment. A previous study identified two CPS interventions that predicted recidivism: psychotherapy for the parent, which was related to a reduced risk of recidivism, and temporary removal of the child from the parent's custody, which was related to an increased recidivism risk. However, counter to expectations, this previous study did not identify any other specific risk factors related to maltreatment recidivism. For the current study, it was hypothesized that (a) cumulative risk (i.e., the total number of risk factors) would significantly predict maltreatment recidivism above and beyond intervention variables in a sample of CPS case files and that (b) therapy for the parent would be related to a reduced likelihood of recidivism. Because it was believed that the relation between temporary removal of a child from the parent's custody and maltreatment recidivism is explained by cumulative risk, the study also hypothesized that that the relation between temporary removal of the child from the parent's custody and recidivism would be mediated by cumulative risk. After performing a hierarchical logistic regression analysis, the first two hypotheses were supported, and an additional predictor, psychotherapy for the child, also was related to reduced chances of recidivism. However, Hypothesis 3 was not supported, as risk did not significantly mediate the relation between temporary removal and recidivism.

  12. Cumulative radiation exposure from diagnostic imaging in intensive care unit patients

    Institute of Scientific and Technical Information of China (English)

    Fiachra Moloney; Daniel Fama; Maria Twomey; Ruth O’Leary; Conor Houlihane; Kevin P Murphy; Siobhan B O’Neill; Owen J O’Connor; Dorothy Breen; Michael M Maher

    2016-01-01

    AIM:To quantify cumulative effective dose of intensive care unit(ICU)patients attributable to diagnostic imaging.METHODS:This was a prospective,interdisciplinary study conducted in the ICU of a large tertiary referral and level 1 trauma center.Demographic and clinical data including age,gender,date of ICU admission,primary reason for ICU admission,APACHE Ⅱ score,length of stay,number of days intubated,date of death or discharge,and re-admission data was collected on all patients admitted over a 1-year period.The overall radiation exposure was quantified by the cumulative effective radiation dose(CED)in millisieverts(mS v)and calculated using reference effective doses published by the United Kingdom National Radiation Protection Board.Pediatric patients were selected for subgroupanalysis.RESULTS:A total of 2737 studies were performedin 421 patients.The total CED was 1704 m Sv with a median CED of 1.5 mS v(IQR 0.04-6.6 mS v).Total CED in pediatric patients was 74.6 mS v with a median CED of 0.07 mS v(IQR 0.01-4.7 mS v).Chest radiography was the most commonly performed examination accounting for 83% of all studies but only 2.7% of total CED.Computed tomography(CT)accounted for 16% of all studies performed and contributed 97% of total CED.Trauma patients received a statistically significant higher dose [median CED 7.7 mS v(IQR 3.5-13.8 mS v)] than medical [median CED 1.4 m Sv(IQR 0.05-5.4 m Sv)] and surgical [median CED 1.6 mS v(IQR 0.04-7.5 mS v)] patients.Length of stay in ICU [OR = 1.12(95%CI:1.079-1.157)] was identified as an independent predictor of receiving a CED greater than 15 mS v.CONCLUSION:Trauma patients and patients with extended ICU admission times are at increased risk of higher CEDs.CED should be minimized where feasible,especially in young patients.

  13. Thermal momentum distribution from shifted boundary conditions

    CERN Document Server

    Giusti, Leonardo

    2011-01-01

    At finite temperature the distribution of the total momentum is an observable characterizing the thermal state of a field theory, and its cumulants are related to thermodynamic potentials. In a relativistic system at zero chemical potential, for instance, the thermal variance of the total momentum is a direct measure of the entropy. We relate the generating function of the cumulants to the ratio of a path integral with properly shifted boundary conditions in the compact direction over the ordinary partition function. In this form it is well suited for Monte-Carlo evaluation, and the cumulants can be extracted straightforwardly. We test the method in the SU(3) Yang--Mills theory, and obtain the entropy density at three different temperatures.

  14. El Carreto o Cumulá - Aspidosperma Dugandii Standl El Carreto o Cumulá - Aspidosperma Dugandii Standl

    Directory of Open Access Journals (Sweden)

    Dugand Armando

    1944-03-01

    Full Text Available Nombres vulgares: Carreto (Atlántico, Bolívar, Magdalena; Cumulá, Cumulá (Cundinamarca, ToIima. Según el Dr. Emilio Robledo (Lecciones de Bot. ed. 3, 2: 544. 1939 el nombre Carreto también es empleado en Puerto Berrío (Antioquia. El mismo autor (loc. cit. da el nombre Comulá para una especie indeterminada de Viburnum en Mariquita (Tolima y J. M. Duque, refiriendose a la misma planta y localidad (en Bot. Gen. Colomb. 340, 356. 1943 atribuye este nombre vulgar al Aspidosperma ellipticum Rusby.  Sin embargo, las muestras de madera de Cumulá o Comulá que yo he examinado, procedentes de la región de Mariquita -una de las cuales me fue recientemente enviada por el distinguido ictiólogo Sr. Cecil Miles- pertenecen sin duda alguna al A. Dugandii StandI. Por otra parte, Santiago Cortés (FI. Colomb. 206. 1898; ed, 2: 239. 1912 cita el Cumulá "de Anapoima y otros lugares del (rio Magdalena" diciendo que pertenece a las Leguminosas, pero la brevísima descripción que este autor hace de la madera "naranjada y notable por densidad, dureza y resistencia a la humedad", me induce a creer que se trata del mismo Cumula coleccionado recientemente en Tocaima, ya que esta población esta situada a pocos kilómetros de Anapoima. Nombres vulgares: Carreto (Atlántico, Bolívar, Magdalena; Cumulá, Cumulá (Cundinamarca, ToIima. Según el Dr. Emilio Robledo (Lecciones de Bot. ed. 3, 2: 544. 1939 el nombre Carreto también es empleado en Puerto Berrío (Antioquia. El mismo autor (loc. cit. da el nombre Comulá para una especie indeterminada de Viburnum en Mariquita (Tolima y J. M. Duque, refiriendose a la misma planta y localidad (en Bot. Gen. Colomb. 340, 356. 1943 atribuye este nombre vulgar al Aspidosperma ellipticum Rusby.  Sin embargo, las muestras de madera de Cumulá o Comulá que yo he examinado, procedentes de la región de Mariquita -una de las cuales me fue recientemente enviada por el distinguido ictiólogo Sr. Cecil Miles- pertenecen sin

  15. Mismatch or cumulative stress : Toward an integrated hypothesis of programming effects

    NARCIS (Netherlands)

    Nederhof, Esther; Schmidt, Mathias V.

    2012-01-01

    This paper integrates the cumulative stress hypothesis with the mismatch hypothesis, taking into account individual differences in sensitivity to programming. According to the cumulative stress hypothesis, individuals are more likely to suffer from disease as adversity accumulates. According to the

  16. Cumulative approaches to track formation under swift heavy ion (SHI) irradiation: Phenomenological correlation with formation energies of Frenkel pairs

    Energy Technology Data Exchange (ETDEWEB)

    Crespillo, M.L., E-mail: mcrespil@utk.edu [Centro de Microanálisis de Materiales, CMAM-UAM, Cantoblanco, Madrid 28049 (Spain); Department of Materials Science & Engineering, University of Tennessee, Knoxville, TN 37996 (United States); Agulló-López, F., E-mail: fal@uam.es [Centro de Microanálisis de Materiales, CMAM-UAM, Cantoblanco, Madrid 28049 (Spain); Zucchiatti, A. [Centro de Microanálisis de Materiales, CMAM-UAM, Cantoblanco, Madrid 28049 (Spain)

    2017-03-01

    Highlights: • Extensive survey formation energies Frenkel pairs and electronic stopping thresholds. • Correlation: track formation thresholds and the energies for Frenkel pair formation. • Formation energies Frenkel pairs discussed in relation to the cumulative mechanisms. • Amorphous track formation mechanisms: defect accumulation models versus melting. • Advantages cumulative models to deal with new hot topics: nuclear-electronic synergy. - Abstract: An extensive survey for the formation energies of Frenkel pairs, as representative candidates for radiation-induced point defects, is presented and discussed in relation to the cumulative mechanisms (CM) of track formation in dielectric materials under swift heavy ion (SHI) irradiation. These mechanisms rely on the generation and accumulation of point defects during irradiation followed by collapse of the lattice once a threshold defect concentration is reached. The physical basis of those approaches has been discussed by Fecht as a defect-assisted transition to an amorphous phase. Although a first quantitative analysis of the CM model was previously performed for LiNbO{sub 3} crystals, we have, here, adopted a broader phenomenological approach. It explores the correlation between track formation thresholds and the energies for Frenkel pair formation for a broad range of materials. It is concluded that the threshold stopping powers can be roughly scaled with the energies required to generate a critical Frenkel pair concentration in the order of a few percent of the total atomic content. Finally, a comparison with the predictions of the thermal spike model is discussed within the analytical Szenes approximation.

  17. Mapping cumulative noise from shipping to inform marine spatial planning.

    Science.gov (United States)

    Erbe, Christine; MacGillivray, Alexander; Williams, Rob

    2012-11-01

    Including ocean noise in marine spatial planning requires predictions of noise levels on large spatiotemporal scales. Based on a simple sound transmission model and ship track data (Automatic Identification System, AIS), cumulative underwater acoustic energy from shipping was mapped throughout 2008 in the west Canadian Exclusive Economic Zone, showing high noise levels in critical habitats for endangered resident killer whales, exceeding limits of "good conservation status" under the EU Marine Strategy Framework Directive. Error analysis proved that rough calculations of noise occurrence and propagation can form a basis for management processes, because spending resources on unnecessary detail is wasteful and delays remedial action.

  18. The Carvedilol Prospective Randomized Cumulative Survival (COPERNICUS) trial.

    Science.gov (United States)

    Eichhorn, Eric J; Bristow, Michael R

    2001-01-01

    Previous trials (Metoprolol CR/XL Randomised Intervention Trial in Congestive Heart Failure [MERIT-HF], Cardiac Insufficiency Bisoprolol Study [CIBIS] II) have demonstrated a mortality benefit of beta-adrenergic blockade in patients with mild to moderate heart failure. The recent Carvedilol Prospective Randomized Cumulative Survival (COPERNICUS) trial has extended these results to a more advanced patient population. This trial did not, however, include patients who could not reach compensation, patients with far advanced heart failure symptoms, or a significant number of black patients. Future studies of beta-blockade may focus on these patients or patients with asymptomatic left ventricular dysfunction.

  19. The Carvedilol Prospective Randomized Cumulative Survival (COPERNICUS trial

    Directory of Open Access Journals (Sweden)

    Bristow Michael R

    2001-02-01

    Full Text Available Abstract Previous trials (Metoprolol CR/XL Randomised Intervention Trial in Congestive Heart Failure [MERIT-HF], Cardiac Insufficiency Bisoprolol Study [CIBIS] II have demonstrated a mortality benefit of β-adrenergic blockade in patients with mild to moderate heart failure. The recent Carvedilol Prospective Randomized Cumulative Survival (COPERNICUS trial has extended these results to a more advanced patient population. This trial did not, however, include patients who could not reach compensation, patients with far advanced heart failure symptoms, or a significant number of black patients. Future studies of β-blockade may focus on these patients or patients with asymptomatic left ventricular dysfunction.

  20. Generalized Cumulative Residual Entropy for Distributions with Unrestricted Supports

    Directory of Open Access Journals (Sweden)

    Noomane Drissi

    2008-01-01

    Full Text Available We consider the cumulative residual entropy (CRE a recently introduced measure of entropy. While in previous works distributions with positive support are considered, we generalize the definition of CRE to the case of distributions with general support. We show that several interesting properties of the earlier CRE remain valid and supply further properties and insight to problems such as maximum CRE power moment problems. In addition, we show that this generalized CRE can be used as an alternative to differential entropy to derive information-based optimization criteria for system identification purpose.

  1. Embryo quality is the main factor affecting cumulative live birth rate after elective single embryo transfer in fresh stimulation cycles.

    Science.gov (United States)

    Niinimäki, Maarit; Veleva, Zdravka; Martikainen, Hannu

    2015-11-01

    The study was aimed to evaluate which factors affect the cumulative live birth rate after elective single embryo transfer in women younger than 36 years. Additionally, number of children in women with more than one delivery per ovum pick-up after fresh elective single embryo transfer and subsequent frozen embryo transfers was assessed. Retrospective cohort study analysing data of a university hospital's infertility clinic in 2001-2010. A total of 739 IVF/ICSI cycles with elective single embryo transfer were included. Analyses were made per ovum pick-up including fresh and subsequent frozen embryo transfers. Factors affecting cumulative live birth rates were examined in uni- and multivariate analyses. A secondary endpoint was the number of children born after all treatments. In the fresh cycles, the live birth rate was 29.2% and the cumulative live birth rate was 51.3%, with a twin rate of 3.4%. In the multivariate analysis, having two (odds ratio (OR) 1.73; 95% confidence interval (CI) 1.12-2.67) or ≥3 top embryos (OR 2.66; 95% CI 1.79-3.95) was associated with higher odds for live birth after fresh and frozen embryo cycles. Age, body mass index, duration of infertility, diagnosis or total gonadotropin dose were not associated with the cumulative live birth rate. In cycles with one top embryo, the cumulative live birth rate was 40.2%, whereas it was 64.1% in those with at least three top embryos. Of women who had a live birth in the fresh cycle, 20.4% had more than one child after all frozen embryo transfers. Among women with three or more top embryos after ovum pick-up, 16.1% gave birth to more than one child. The cumulative live birth rate in this age group varies from 40% to 64% and is dependent on the quality of embryos. Women with three or more top embryos have good chance of having more than one child per ovum pick-up without elevated risk of multiple pregnancies. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  2. Determining source cumulants in femtoscopy with Gram-Charlier and Edgeworth series

    DEFF Research Database (Denmark)

    Eggers, H. C.; De Kock, M. B.; Schmiegel, Jürgen

    2011-01-01

    Lowest-order cumulants provide important information on the shape of the emission source in femtoscopy. For the simple case of noninteracting identical particles, we show how the fourth-order source cumulant can be determined from measured cumulants in momentum space. The textbook Gram–Charlier s...

  3. High-resolution harmonic retrieval using the full fourth-order cumulant

    NARCIS (Netherlands)

    Vossen, S.H.J.A.; Naus, H.W.L.; Zwamborn, A.P.M.

    2010-01-01

    The harmonic retrieval (HR) problem concerns the estimation of the frequencies in a sum of real or complex harmonics. Both correlation and cumulant-based approaches are used for this purpose. Cumulant-based HR algorithms use a single 1-D slice of the fourth-order cumulant that is estimated directly

  4. 75 FR 69662 - Workshop: Cumulative Mixtures Risk of Six Selected Phthalates in Support of Summary Information...

    Science.gov (United States)

    2010-11-15

    ... AGENCY Workshop: Cumulative Mixtures Risk of Six Selected Phthalates in Support of Summary Information on...: Notice of Peer Consultation Workshop on the Cumulative Mixtures Risk of Six Selected Phthalates; Request... phthalates as set forth in the National Academies of Science (NAS) report ``Phthalates and Cumulative...

  5. The seven-year cumulative survival rate of Osstem implants

    Science.gov (United States)

    Kim, Young-Kyun; Kim, Bum-Su; Yun, Pil-Young; Mun, Sang-Un; Yi, Yang-Jin; Jeong, Kyung-In

    2014-01-01

    Objectives This study was performed to analyze the cumulative survival rate of Osstem implants (Osstem Implant Co., Ltd.) over a seven-year period. Materials and Methods A total of 105 patients who had 467 Osstem implants that were placed at the Section of Dentistry, Seoul National University Bundang Hospital (Seongnam, Korea) from June 2003 through December 2005 were analyzed. The life table method and a cross-tubulation analysis, log rank test were used to evaluate the survival curve and the influence that the prognostic factors. The prognostic factors, i.e., age and gender of patients, diameter and length, type of implants, bone graft history and loading time were determined with a Cox proportional hazard model based on logistic regression analysis. Results The seven-year cumulative survival rate of Osstem implants was 95.37%. The Cox proportional hazard model revealed that the following factors had a significant influence on survival rate; increased diameter, reduced prosthetic loading period and performance of bone grafting. Conclusion The osstem implants showed satisfactory results over the seven-year study period. PMID:24868503

  6. Cumulative human threats on fish biodiversity components in Tunisian waters

    Directory of Open Access Journals (Sweden)

    F. BEN RAIS LASRAM

    2015-02-01

    Full Text Available Human activities are increasingly impacting biodiversity. To improve conservation planning measures in an ecosystem-based management context, we need to explore how the effects of these activities interact with different biodiversity components. In this study, we used a semi-quantitative method to assess the cumulative impacts of human activities on three biodiversity components (species richness, phylogenetic diversity, and functional diversity in Tunisia’s exclusive economic zone. For each of the nine activities considered, we developed an understanding of their effects from local studies and the expert opinion of stakeholders with country-specific experience. We mapped the cumulative effects and the three biodiversity components and then assessed the degree to which these elements overlapped using an overlap index. This is the first time such an assessment has been made for Tunisia’s marine ecosystems and our assessment highlight the inappropriateness of current conservation measures. The results of this study have specific application for the prioritization of future management actions.

  7. Cumulative human threats on fish biodiversity components in Tunisian waters

    Directory of Open Access Journals (Sweden)

    F. BEN RAIS LASRAM

    2014-06-01

    Full Text Available Human activities are increasingly impacting biodiversity. To improve conservation planning measures in an ecosystem-based management context, we need to explore how the effects of these activities interact with different biodiversity components. In this study, we used a semi-quantitative method to assess the cumulative impacts of human activities on three biodiversity components (species richness, phylogenetic diversity, and functional diversity in Tunisia’s exclusive economic zone. For each of the nine activities considered, we developed an understanding of their effects from local studies and the expert opinion of stakeholders with country-specific experience. We mapped the cumulative effects and the three biodiversity components and then assessed the degree to which these elements overlapped using an overlap index. This is the first time such an assessment has been made for Tunisia’s marine ecosystems and our assessment highlight the inappropriateness of current conservation measures. The results of this study have specific application for the prioritization of future management actions.

  8. Cumulative dietary exposure of the population of Denmark to pesticides.

    Science.gov (United States)

    Jensen, Bodil Hamborg; Petersen, Annette; Nielsen, Elsa; Christensen, Tue; Poulsen, Mette Erecius; Andersen, Jens Hinge

    2015-09-01

    We used the Hazard Index (HI) method to carry out a cumulative risk assessment after chronic dietary exposure to all monitored pesticides in fruit, vegetables and cereals for various consumer groups in Denmark. Residue data for all the pesticides were obtained from the Danish monitoring programme during the period 2004-2011. Food consumption data were obtained from DANSDA (the DAnish National Survey of Diet and physical Activity) for the period 2005-2008. The calculations were made using three different models to cope with residues below the limit of reporting (LOR). We concluded that a model that included processing factors and set non-detects to ½ LOR, but limited the correction (Model 3), gave the most realistic exposure estimate. With Model 3 the HI was calculated to be 0.44 for children and 0.18 for adults, indicating that there is no risk of adverse health effects following chronic cumulative exposure to the pesticides found in fruit, vegetables and cereals on the Danish market. The HI was below 1 even for consumers who eat more than 550 g of fruit and vegetables per day, corresponding to 1/3 of the population. Choosing Danish-produced commodities whenever possible could reduce the HI by a factor of 2.

  9. Extraction of Facial Feature Points Using Cumulative Histogram

    CERN Document Server

    Paul, Sushil Kumar; Bouakaz, Saida

    2012-01-01

    This paper proposes a novel adaptive algorithm to extract facial feature points automatically such as eyebrows corners, eyes corners, nostrils, nose tip, and mouth corners in frontal view faces, which is based on cumulative histogram approach by varying different threshold values. At first, the method adopts the Viola-Jones face detector to detect the location of face and also crops the face region in an image. From the concept of the human face structure, the six relevant regions such as right eyebrow, left eyebrow, right eye, left eye, nose, and mouth areas are cropped in a face image. Then the histogram of each cropped relevant region is computed and its cumulative histogram value is employed by varying different threshold values to create a new filtering image in an adaptive way. The connected component of interested area for each relevant filtering image is indicated our respective feature region. A simple linear search algorithm for eyebrows, eyes and mouth filtering images and contour algorithm for nos...

  10. A Cumulant-based Analysis of Nonlinear Magnetospheric Dynamics

    Energy Technology Data Exchange (ETDEWEB)

    Jay R. Johnson; Simon Wing

    2004-01-28

    Understanding magnetospheric dynamics and predicting future behavior of the magnetosphere is of great practical interest because it could potentially help to avert catastrophic loss of power and communications. In order to build good predictive models it is necessary to understand the most critical nonlinear dependencies among observed plasma and electromagnetic field variables in the coupled solar wind/magnetosphere system. In this work, we apply a cumulant-based information dynamical measure to characterize the nonlinear dynamics underlying the time evolution of the Dst and Kp geomagnetic indices, given solar wind magnetic field and plasma input. We examine the underlying dynamics of the system, the temporal statistical dependencies, the degree of nonlinearity, and the rate of information loss. We find a significant solar cycle dependence in the underlying dynamics of the system with greater nonlinearity for solar minimum. The cumulant-based approach also has the advantage that it is reliable even in the case of small data sets and therefore it is possible to avoid the assumption of stationarity, which allows for a measure of predictability even when the underlying system dynamics may change character. Evaluations of several leading Kp prediction models indicate that their performances are sub-optimal during active times. We discuss possible improvements of these models based on this nonparametric approach.

  11. Cumulative Effects Assessment: Linking Social, Ecological, and Governance Dimensions

    Directory of Open Access Journals (Sweden)

    Marian Weber

    2012-06-01

    Full Text Available Setting social, economic, and ecological objectives is ultimately a process of social choice informed by science. In this special feature we provide a multidisciplinary framework for the use of cumulative effects assessment in land use planning. Forest ecosystems are facing considerable challenges driven by population growth and increasing demands for resources. In a suite of case studies that span the boreal forest of Western Canada to the interior Atlantic forest of Paraguay we show how transparent and defensible methods for scenario analysis can be applied in data-limited regions and how social dimensions of land use change can be incorporated in these methods, particularly in aboriginal communities that have lived in these ecosystems for generations. The case studies explore how scenario analysis can be used to evaluate various land use options and highlight specific challenges with identifying social and ecological responses, determining thresholds and targets for land use, and integrating local and traditional knowledge in land use planning. Given that land use planning is ultimately a value-laden and often politically charged process we also provide some perspective on various collective and expert-based processes for identifying cumulative impacts and thresholds. The need for good science to inform and be informed by culturally appropriate democratic processes calls for well-planned and multifaceted approaches both to achieve an informed understanding of both residents and governments of the interactive and additive changes caused by development, and to design action agendas to influence such change at the ecological and social level.

  12. Cumulative hierarchies and computability over universes of sets

    Directory of Open Access Journals (Sweden)

    Domenico Cantone

    2008-05-01

    Full Text Available Various metamathematical investigations, beginning with Fraenkel’s historical proof of the independence of the axiom of choice, called for suitable definitions of hierarchical universes of sets. This led to the discovery of such important cumulative structures as the one singled out by von Neumann (generally taken as the universe of all sets and Godel’s universe of the so-called constructibles. Variants of those are exploited occasionally in studies concerning the foundations of analysis (according to Abraham Robinson’s approach, or concerning non-well-founded sets. We hence offer a systematic presentation of these many structures, partly motivated by their relevance and pervasiveness in mathematics. As we report, numerous properties of hierarchy-related notions such as rank, have been verified with the assistance of the ÆtnaNova proof-checker.Through SETL and Maple implementations of procedures which effectively handle the Ackermann’s hereditarily finite sets, we illustrate a particularly significant case among those in which the entities which form a universe of sets can be algorithmically constructed and manipulated; hereby, the fruitful bearing on pure mathematics of cumulative set hierarchies ramifies into the realms of theoretical computer science and algorithmics.

  13. Prefiltering and Cumulant Based Harmonic Retrieval in Mixed ARMA Noises

    Institute of Scientific and Technical Information of China (English)

    LIShenghong; LIJianhua; XUEZhi; CHENLiya

    2005-01-01

    Harmonic retrieval is an important issue in the the field of statistical signal processing. However, in the case of harmonic retrieval in mixed colored Gaussian and Non-Gaussian Autoregressive movingaverage (ARMA) noises, the corresponding existing approaches can not retrieve a harmonic signal either with quadratic phase coupling components, or with cubic phase coupling components, or when the colored non-Gaussian ARMA noise is symmetrically distributed. In this paper, a new general approach is proposed to retrieve a one-dimensional real harmonic signal in the above mixed ARMA noises. A suitable filter is first used to remove all the sharp power spectrum peaks of the noisy observed process, then some kind of fourth-order cumulant is employed to identify the Autoregressive (AR) parameter values of the colored non-Gaussian ARMA noise model. After the real noisy observed data are filtered with the identified AR parameter values again, cumulant based methods can be made use of to retrieve the harmonics. The proposed new approach can be applied to retrieve a one-dimensional real harmonic signal in the above mixed colored Gaussian and non-Gaussian ARMA noises with no restrictions on the phase coupling of the harmonics and the distribution of the colored non-Gaussian ARMA noise. Simulation examples are presented to demonstrate its effectiveness.

  14. Petrogenesis of the nakhlite meteorites: Evidence from cumulate mineral zoning

    Energy Technology Data Exchange (ETDEWEB)

    Harvey, R.P.; McSween, H.Y. Jr. (Univ. of Tennessee, Knoxville (United States))

    1992-04-01

    A simple igneous petrogenesis for the meteorite Nakhla has previously been called into question because Mg/Fe ratios in olivine indicate substantial disequilibrium between the predominant cumulus minerals (olivine and augite). Comparative analyses of simulated diffusive zoning and the observed cumulus mineral zoning for all three nakhlites (Nakhla, Governador Valadares, and Lafayette) show that their current compositions do not necessarily reflect parental magma compositions. Instead, diffusion has altered primary cumulus compositions to varying degrees, Nakhla being the least affected, and Lafayette being almost completely re-equilibrated. Only the cores of augite grains in Nakhla and Governador Valadares appear to have preserved their original compositions. Mineral zoning in each meteorite is strongly concentric around mesostasis areas, suggesting that reaction with intercumulus liquid has controlled the observed zoning. The presence of pigeonite and orthopyroxene overgrowths in Nakhla and Governador Valadares, and of poikilitic orthopyroxene enclosing olivine relicts in Lafayette, indicate substantial late-magmatic reactions. Two-pyroxene geothermometry for Lafayette indicates temperatures around 95C, suggesting subsolidus equilibration as well. The nakhlites appear to be a series of relatively simple cumulate rocks which have undergone various amounts of late-magmatic and subsolidus diffusion, possibly reflecting their relative positions in a cooling cumulate pile.

  15. The cumulative impact of annual coral bleaching can turn some coral species winners into losers.

    Science.gov (United States)

    Grottoli, Andréa G; Warner, Mark E; Levas, Stephen J; Aschaffenburg, Matthew D; Schoepf, Verena; McGinley, Michael; Baumann, Justin; Matsui, Yohei

    2014-12-01

    Mass coral bleaching events caused by elevated seawater temperatures result in extensive coral loss throughout the tropics, and are projected to increase in frequency and severity. If bleaching becomes an annual event later in this century, more than 90% of coral reefs worldwide may be at risk of long-term degradation. While corals can recover from single isolated bleaching and can acclimate to recurring bleaching events that are separated by multiple years, it is currently unknown if and how they will survive and possibly acclimatize to annual coral bleaching. Here, we demonstrate for the first time that annual coral bleaching can dramatically alter thermal tolerance in Caribbean corals. We found that high coral energy reserves and changes in the dominant algal endosymbiont type (Symbiodinium spp.) facilitated rapid acclimation in Porites divaricata, whereas low energy reserves and a lack of algal phenotypic plasticity significantly increased susceptibility in Porites astreoides to bleaching the following year. Phenotypic plasticity in the dominant endosymbiont type of Orbicella faveolata did not prevent repeat bleaching, but may have facilitated rapid recovery. Thus, coral holobiont response to an isolated single bleaching event is not an accurate predictor of its response to bleaching the following year. Rather, the cumulative impact of annual coral bleaching can turn some coral species 'winners' into 'losers', and can also facilitate acclimation and turn some coral species 'losers' into 'winners'. Overall, these findings indicate that cumulative impact of annual coral bleaching could result in some species becoming increasingly susceptible to bleaching and face a long-term decline, while phenotypically plastic coral species will acclimatize and persist. Thus, annual coral bleaching and recovery could contribute to the selective loss of coral diversity as well as the overall decline of coral reefs in the Caribbean.

  16. Cumulative effects of road de-icing salt on amphibian behavior.

    Science.gov (United States)

    Denoël, Mathieu; Bichot, Marion; Ficetola, Gentile Francesco; Delcourt, Johann; Ylieff, Marc; Kestemont, Patrick; Poncin, Pascal

    2010-08-15

    Despite growing evidence of the detrimental effect of chemical substances on organisms, limited research has focused on changes in behavioral patterns, in part due to the difficulties to obtain detailed quantitative data. Recent developments in efficient computer-based video analyses have allowed testing pesticide effects on model species such as the zebrafish. However, these new techniques have not yet been applied to amphibians and directly to conservation issues, i.e., to assess toxicological risks on threatened species. We used video-tracking analyses to test a quantitative effect of an environmental contaminant on the locomotion of amphibian tadpoles (Rana temporaria) by taking into account cumulative effects. Because recent research has demonstrated effects of de-icing salts on survival and community structure, we used sodium chloride in our experimental design (25 replicates, 4 concentrations, 4 times) to test for an effect at the scale of behavior at environmentally relevant concentrations. Analysis of 372 1-h video-tracks (5 samples/s) showed a complex action of salts on behavioral patterns with a dose and cumulative response over time. Although no effects were found on mortality or growth, the highest salt concentrations reduced the speed and movement of tadpoles in comparison with control treatments. The reduced locomotor performance could have detrimental consequences in terms of tadpoles' responses to competition and predation and may be an indicator of the low concentration effect of the contaminant. On one hand, this study demonstrates the usefulness of examining behavior to address conservation issues and understand the complex action of environmental factors and, more particularly, pollutants on organisms. On the other hand, our results highlight the need of new computerized techniques to quantitatively analyze these patterns.

  17. [Analysis of the cumulative solar ultraviolet radiation in Mexico].

    Science.gov (United States)

    Castanedo-Cázares, Juan Pablo; Torres-Álvarez, Bertha; Portales-González, Bárbara; Martínez-Rosales, Karla; Hernández-Blanco, Diana

    2016-01-01

    The incidence of skin cancer has increased in Mexico in recent years. Ultraviolet radiation is the main risk factor associated. Due to the need to develop strategies to prevent skin cancer, the aim of the study was to estimate the UV intensity in several representative regions of Mexico, the average annual UV dose of these populations, and the potential benefit of applying sunscreen at different ages. The intensity of UV radiation was quantified by remote and terrestrial radiometry. The dose of UV exposure was measured in minimal erythema doses using validated models for face and arms. The benefit of using a sunscreen was calculated with the use of a sunscreen with SPF 15 from birth to age 70. The UV radiation is lower in December and greater in the period from May to July. The region with a lower annual dose is Tijuana; and the higher annual dose is in the Mexico City area. The annual difference between these regions was 58 %. Through life, a low SPF sunscreen can reduce up to 66 % of the received UV dose. The geographical location is a risk factor for accumulation of UV radiation in Mexico. Since childhood, people receive high amounts of it; however, most of this dose can be reduced using any commercially available sunscreen, if applied strategically.

  18. The excess risk of major osteoporotic fractures in hypothyroidism is driven by cumulative hyperthyroid as opposed to hypothyroid time

    DEFF Research Database (Denmark)

    Abrahamsen, Bo; Jørgensen, Henrik L; Laulund, Anne Sofie

    2015-01-01

    The long-term relationship between hypothyroidism and fracture risk is challenging to dissect because of the modifying influence of subsequent thyroxine replacement with the potential for excessive replacement doses. We studied changes in serum thyrotropin concentration (TSH) over time and associ......The long-term relationship between hypothyroidism and fracture risk is challenging to dissect because of the modifying influence of subsequent thyroxine replacement with the potential for excessive replacement doses. We studied changes in serum thyrotropin concentration (TSH) over time...... as a predictor of fracture risk in postmenopausal women whereas hypothyroid time predicted increased fracture risk in men below age 75 years. In conclusion, among patients who present with an elevated TSH, the long-term risk of hip and other osteoporotic fractures is strongly related to the cumulative duration...

  19. Cyclosporine induces progressive attenuation of baroreceptor heart rate response and cumulative pressor response in conscious unrestrained rats.

    Science.gov (United States)

    Shaltout, Hossam A; Abdel-Rahman, Abdel A

    2003-06-01

    Cyclosporine A (CsA) use is associated with hypertension and reduced baroreceptor sensitivity (BRS), but the underlying mechanisms remain unresolved. In this study, we investigated whether CsA attenuation of BRS is 1) dependent on treatment regimen, and 2) causative of the pressor response. Furthermore, we investigated whether a reduction in plasma testosterone contributes to BRS attenuation caused by short-term CsA administration. The effects of the clinically used CsA formulation (15 mg/kg/day i.v. for 5 days) on mean arterial pressure (MAP), heart rate, BRS, and body weight were investigated in conscious rats. CsA caused reproducible pressor responses (15.1 +/- 3.0 mm Hg) starting after the first dose and continuing through the 5 days of the study. BRS and baseline MAP were inversely related in the CsA group because of a progressive reduction in BRS, which started on day 2 and reached approximately 50% of baseline on day 5 and a cumulative elevation in MAP. The inverse BRS and MAP responses required daily administration of CsA because neither response was evident throughout the 5-day observation period after a single dose of CsA. Plasma testosterone levels were similar in all groups, whereas the body weight decreased approximately 10% in the CsA group on day 5. These findings suggest 1) CsA attenuation of BRS is relatively rapid and cumulative; 2) the attenuation of BRS may contribute to the delayed, but not to the acute, pressor elicited by CsA; and 3) the cumulative reduction in BRS caused by short-term (5-day) CsA treatment is not testosterone-related.

  20. Cumulative Ocean Volume Estimates of the Solar System

    Science.gov (United States)

    Frank, E. A.; Mojzsis, S. J.

    2010-12-01

    Although there has been much consideration for habitability in silicate planets and icy bodies, this information has never been quantitatively gathered into a single approximation encompassing our solar system from star to cometary halo. Here we present an estimate for the total habitable volume of the solar system by constraining our definition of habitable environments to those to which terrestrial microbial extremophiles could theoretically be transplanted and yet survive. The documented terrestrial extremophile inventory stretches environmental constraints for habitable temperature and pH space of T ~ -15oC to 121oC and pH ~ 0 to 13.5, salinities >35% NaCl, and gamma radiation doses of 10,000 to 11,000 grays [1]. Pressure is likely not a limiting factor to life [2]. We applied these criteria in our analysis of the geophysical habitable potential of the icy satellites and small icy bodies. Given the broad spectrum of environmental tolerance, we are optimistic that our pessimistic estimates are conservative. Beyond the reaches of our inner solar system's conventional habitable zone (Earth, Mars and perhaps Venus) is Ceres, a dwarf planet in the habitable zone that could possess a significant liquid water ocean if that water contains anti-freezing species [3]. Yet further out, Europa is a small icy satellite that has generated much excitement for astrobiological potential due to its putative subsurface liquid water ocean. It is widely promulgated that the icy moons Enceladus, Triton, Callisto, Ganymede, and Titan likewise have also sustained liquid water oceans. If oceans in Europa, Enceladus, and Triton have direct contact with a rocky mantle hot enough to melt, hydrothermal vents could provide an energy source for chemotrophic organisms. Although oceans in the remaining icy satellites may be wedged between two layers of ice, their potential for life cannot be precluded. Relative to the Jovian style of icy satellites, trans-neptunian objects (TNOs) - icy bodies

  1. Testing a cumulative and aggregate exposure model using biomonitoring studies and dietary records for Italian vineyard spray operators.

    Science.gov (United States)

    Kennedy, Marc C; Glass, C Richard; Fustinoni, Silvia; Moretto, Angelo; Mandic-Rajcevic, Stefan; Riso, Patrizia; Turrini, Aida; van der Voet, Hilko; Hetmanski, Michel T; Fussell, Richard J; van Klaveren, Jacob D

    2015-05-01

    The need for improved tools to estimate the cumulative and aggregate exposure to compounds such as plant protection products (PPPs) is recognised in the EU Regulation 1107/2009. A new model has been developed to estimate the exposure within a population to single compounds or compounds within a Cumulative Action Group, considering dietary and non-dietary sources and multiple exposure routes. To test the model a field study was carried out in Italy with operators applying tebuconazole fungicides, with measurements of dermal exposure collected. Whole urine samples were collected and analysed to provide values for the absorbed dose of tebuconazole, with duplicate diet samples collected and analysed as a measure of dietary exposures. The model provided predicted values of exposure for combined dietary and non-dietary routes of exposures which were compared to the measured absorbed dose values based on urinary analysis. The model outputs provided mean daily exposure values of 1.77 (± 1.96) µg a.s./kg BW which are comparable to measured mean values from the biomonitoring field study of 1.73 (± 1.31) µg a.s./kg BW. To supplement the limited measurement data available, comparisons against other models were also made and found to be comparable.

  2. Use of a Cumulative Risk Scale to Predict Poor Intellectual and Academic Outcomes in Childhood Epilepsy.

    Science.gov (United States)

    Kavanaugh, Brian C; Scarborough, Vanessa Ramos; Salorio, Cynthia F

    2016-06-01

    Discrete risk factors for poor outcomes in childhood epilepsy have been identified, but it is unclear whether the combined effect of several risk factors better predicts outcome. The Epilepsy Cumulative Risk Scale was developed to quantify cumulative risk for poor outcomes in childhood epilepsy. Participants included 156 clinic-referred children with epilepsy. The Epilepsy Cumulative Risk Scale was developed using variables previously associated with functional outcomes. Scale utility was examined through its association with intellectual and academic functioning. All Epilepsy Cumulative Risk Scale variables were significantly associated with functioning. The Total Score (ie, cumulative effect) was most strongly correlated with cognition and academic skills. A Total Score ≥ 5 had the best sensitivity and specificity for differentiating those at high risk for poor outcomes. The Epilepsy Cumulative Risk Scale shows promise as a practical, data-driven tool for quantification of cumulative risk for poor outcomes in childhood epilepsy and may be helpful in detecting those needing referral for additional services.

  3. Deformation and fracture of a plate under thermal shock

    Energy Technology Data Exchange (ETDEWEB)

    Aptukov, V.N.; Pozdeev, A.A.

    1986-01-01

    The wave processes associated with thermal shock give rise to cumulative tensile stresses whose magnitude and location are determined by the plate geometry, the heating region, and the spatial distribution of the heat sources. Here, the wave processes, damage accumulation, and the development of macrofracture zones during thermal shock are analyzed using a two-dimensional axisymmetric formulation. The evolution of macrocracks during thermal shock in a plate, a cylinder, and a partially heated plate is shown graphically. 14 references.

  4. Mathematical modeling of detonation initiation via flow cumulation effects

    Science.gov (United States)

    Semenov, I.; Utkin, P.; Akhmedyanov, I.

    2016-07-01

    The paper concerns two problems connected with the idea of gaseous detonation initiation via flow cumulation effects and convergence of relatively weak shock waves (SW). The first one is the three-dimensional (3D) numerical investigation of shock-to-detonation transition (SDT) in methane-air mixture in a tube with parabolic contraction followed by the tube section of narrow diameter and conical expansion. The second problem is the numerical study of the start-up of the model small-scale hydrogen electrochemical pulse detonation engine with the use of electrical discharge generating the toroidal SW. The investigation is performed by means of numerical simulation with the use of modern high-performance computing systems.

  5. Practical management of cumulative anthropogenic impacts with working marine examples

    DEFF Research Database (Denmark)

    Kyhn, Line Anker; Wright, Andrew J.

    2014-01-01

    for petroleum. Human disturbances, including the noise almost ubiquitously associated with human activity, are likely to increase the incidence, magnitude, and duration of adverse effects on marine life, including stress responses. Stress responses have the potential to induce fitness consequences...... for individuals, which add to more obvious directed takes (e.g., hunting or fishing) to increase the overall population-level impact. To meet the requirements of marine spatial planning and ecosystem-based management, many efforts are ongoing to quantify the cumulative impacts of all human actions on marine...... species or populations. Meanwhile, regulators face the challenge of managing these accumulating and interacting impacts with limited scientific guidance. We believe there is scientific support for capping the level of impact for (at a minimum) populations in decline or with unknown statuses. This cap...

  6. Effects of Surface Emitting and Cumulative Collisions on Elliptic Flow

    Institute of Scientific and Technical Information of China (English)

    LIU Jian-Li; WU Feng-Juan; ZHANG Jing-Bo; TANG Gui-Xin; HUO Lei

    2008-01-01

    @@ The integral and differential elliptic flow of partons is calculated using the multiphase transport model for Au+Au collisions at centre-of-mass energy √SNN=200 GeV.It is shown that elliptic flow of partons freezing out at early time,which is affected mainly by surface emittance,decreases with time and elliptic flow of partons freezing out at late time,which is dominated by cumulative collisions,increases with time.The elliptic flow of partons freezing out early has a large contribution to the flatting of curve of final differential elliptic flow at large transverse momentum.It is argued that the effect of surface emittance is not neglectable.

  7. Modelling the evolution and diversity of cumulative culture

    Science.gov (United States)

    Enquist, Magnus; Ghirlanda, Stefano; Eriksson, Kimmo

    2011-01-01

    Previous work on mathematical models of cultural evolution has mainly focused on the diffusion of simple cultural elements. However, a characteristic feature of human cultural evolution is the seemingly limitless appearance of new and increasingly complex cultural elements. Here, we develop a general modelling framework to study such cumulative processes, in which we assume that the appearance and disappearance of cultural elements are stochastic events that depend on the current state of culture. Five scenarios are explored: evolution of independent cultural elements, stepwise modification of elements, differentiation or combination of elements and systems of cultural elements. As one application of our framework, we study the evolution of cultural diversity (in time as well as between groups). PMID:21199845

  8. Ratcheting up the ratchet: on the evolution of cumulative culture.

    Science.gov (United States)

    Tennie, Claudio; Call, Josep; Tomasello, Michael

    2009-08-27

    Some researchers have claimed that chimpanzee and human culture rest on homologous cognitive and learning mechanisms. While clearly there are some homologous mechanisms, we argue here that there are some different mechanisms at work as well. Chimpanzee cultural traditions represent behavioural biases of different populations, all within the species' existing cognitive repertoire (what we call the 'zone of latent solutions') that are generated by founder effects, individual learning and mostly product-oriented (rather than process-oriented) copying. Human culture, in contrast, has the distinctive characteristic that it accumulates modifications over time (what we call the 'ratchet effect'). This difference results from the facts that (i) human social learning is more oriented towards process than product and (ii) unique forms of human cooperation lead to active teaching, social motivations for conformity and normative sanctions against non-conformity. Together, these unique processes of social learning and cooperation lead to humans' unique form of cumulative cultural evolution.

  9. Cumulative Laws,Team Assembling Mechanisms Determining Network Structure

    Institute of Scientific and Technical Information of China (English)

    WU Bin; LIU Qi; YE Qi

    2008-01-01

    A number of researching works have shed light on the field of complex networks recently.We investigate a wide range of real-world networks and find several interesting phenomena.Firstly,almost all of these networks evolve by overlapping new small graphs on former networks.Secondly,not only the degree sequence of the mature network follows a power-law distribution,but also the distribution of the cumulative occurrence times during the growing process are revealed to have a heavy tail.Existing network evolving models do not provide interpretation to these phenomena.We suggest a model based on the team assembling mechanism,which is extracted from the growing processes of real-world networks and requires simple parameters,and produces networks exhibiting these properties observed in the present study and in previous works.

  10. Modelling the evolution and diversity of cumulative culture.

    Science.gov (United States)

    Enquist, Magnus; Ghirlanda, Stefano; Eriksson, Kimmo

    2011-02-12

    Previous work on mathematical models of cultural evolution has mainly focused on the diffusion of simple cultural elements. However, a characteristic feature of human cultural evolution is the seemingly limitless appearance of new and increasingly complex cultural elements. Here, we develop a general modelling framework to study such cumulative processes, in which we assume that the appearance and disappearance of cultural elements are stochastic events that depend on the current state of culture. Five scenarios are explored: evolution of independent cultural elements, stepwise modification of elements, differentiation or combination of elements and systems of cultural elements. As one application of our framework, we study the evolution of cultural diversity (in time as well as between groups).

  11. Cumulative early life adversity predicts longevity in wild baboons.

    Science.gov (United States)

    Tung, Jenny; Archie, Elizabeth A; Altmann, Jeanne; Alberts, Susan C

    2016-04-19

    In humans and other animals, harsh circumstances in early life predict morbidity and mortality in adulthood. Multiple adverse conditions are thought to be especially toxic, but this hypothesis has rarely been tested in a prospective, longitudinal framework, especially in long-lived mammals. Here we use prospective data on 196 wild female baboons to show that cumulative early adversity predicts natural adult lifespan. Females who experience ≥3 sources of early adversity die a median of 10 years earlier than females who experience ≤1 adverse circumstances (median lifespan is 18.5 years). Females who experience the most adversity are also socially isolated in adulthood, suggesting that social processes partially explain the link between early adversity and adult survival. Our results provide powerful evidence for the developmental origins of health and disease and indicate that close ties between early adversity and survival arise even in the absence of health habit and health care-related explanations.

  12. The cumulative effect of risk compensation on infection preventive measures.

    Science.gov (United States)

    Maxin, Daniel; Sega, Laurentiu; Eaton, Lisa

    2016-12-01

    We study several epidemic models (with and without gender structure) that incorporate risk compensation behavior in response to a lower chance of acquiring the infection as a result of preventive measures that are only partially effective. We show that the cumulative risk compensation that occurs between a high risk susceptible and infectious individual may play an important role in whether the implementation of these measures is successful in lowering the epidemic reproductive number. In addition, we show that certain levels of risk compensation may cancel the benefit of the low infection risk practiced by diagnosed infectious individuals when the goal is a reduction of the epidemic reproductive number. Copyright © 2016 Elsevier Inc. All rights reserved.

  13. Cumulative semantic interference for associative relations in language production.

    Science.gov (United States)

    Rose, Sebastian Benjamin; Abdel Rahman, Rasha

    2016-07-01

    Associations between conceptual representations and thematic relations play an important role in the organization of semantic memory. However, language production research on semantic context effects shows that associative (e.g., dog and bone) and categorical relations (dog and horse) seem to diverge. While categorical contexts typically induce semantic interference that has traditionally been taken to reflect competitive lexical selection, evidence for comparable associative modulations is rare. In three experiments we tested whether thematic associations between objects induce cumulative interference in the continuous naming paradigm, assuming that this paradigm hampers lexical selection via the activation of highly active lexical cohorts steadily increasing in size. Indeed, naming times increased linearly with each newly named member of thematic contexts irrespective of the pre-activation of associations before the naming task (Experiment 1), and irrespective of whether categorical links were partially included (Experiments 1 and 2) or entirely absent (Experiment 3). These findings demonstrate that different types of semantic relations induce interference.

  14. EXPERIMENTAL VALIDATION OF CUMULATIVE SURFACE LOCATION ERROR FOR TURNING PROCESSES

    Directory of Open Access Journals (Sweden)

    Adam K. Kiss

    2016-02-01

    Full Text Available The aim of this study is to create a mechanical model which is suitable to investigate the surface quality in turning processes, based on the Cumulative Surface Location Error (CSLE, which describes the series of the consecutive Surface Location Errors (SLE in roughing operations. In the established model, the investigated CSLE depends on the currently and the previously resulted SLE by means of the variation of the width of cut. The phenomenon of the system can be described as an implicit discrete map. The stationary Surface Location Error and its bifurcations were analysed and flip-type bifurcation was observed for CSLE. Experimental verification of the theoretical results was carried out.

  15. Cumulative protons in 12C fragmentation at intermediate energy

    Directory of Open Access Journals (Sweden)

    Abramov B.M.

    2014-03-01

    Full Text Available In the FRAGM experiment at heavy ion accelerator complex TWAC-ITEP, the proton yields at an angle 3.5° have been measured in fragmentation of carbon ions at T0 = 0.3, 0.6, 0.95 and 2.0 GeV/nucleon on beryllium target. The data are presented as invariant proton yields on cumulative variable x in the range 0.9 < x < 2.4. Proton spectra cover six orders of invariant cross section magnitude. They have been analyzed in the framework of quark cluster fragmentation model. Fragmentation functions of quarkgluon string model are used. The probabilities of the existence of multi-quark clusters in carbon nuclei are estimated to be 8–12% for six-quark clusters and 0.2–0.6% for ninequark clusters.

  16. The modified cumulant expansion for two-dimensional isotropic turbulence

    Science.gov (United States)

    Tatsumi, T.; Yanase, S.

    1981-09-01

    The two-dimensional isotropic turbulence in an incompressible fluid is investigated using the modified zero fourth-order cumulant approximation. The dynamical equation for the energy spectrum obtained under this approximation is solved numerically and the similarity laws governing the solution in the energy-containing and enstrophy-dissipation ranges are derived analytically. At large Reynolds numbers the numerical solutions yield the k to the -3rd power inertial subrange spectrum which was predicted by Kraichnan (1967), Leith (1968) and Batchelor (1969), assuming a finite enstrophy dissipation in the inviscid limit. The energy-containing range is found to satisfy an inviscid similarity while the enstrophy-dissipation range is governed by the quasi-equilibrium similarity with respect to the enstrophy dissipation as proposed by Batchelor (1969). There exists a critical time which separates the initial period and the similarity period in which the enstrophy dissipation vanishes and remains non-zero respectively in the inviscid limit.

  17. Cumulative Incidence Association Models for Bivariate Competing Risks Data.

    Science.gov (United States)

    Cheng, Yu; Fine, Jason P

    2012-03-01

    Association models, like frailty and copula models, are frequently used to analyze clustered survival data and evaluate within-cluster associations. The assumption of noninformative censoring is commonly applied to these models, though it may not be true in many situations. In this paper, we consider bivariate competing risk data and focus on association models specified for the bivariate cumulative incidence function (CIF), a nonparametrically identifiable quantity. Copula models are proposed which relate the bivariate CIF to its corresponding univariate CIFs, similarly to independently right censored data, and accommodate frailty models for the bivariate CIF. Two estimating equations are developed to estimate the association parameter, permitting the univariate CIFs to be estimated either parametrically or nonparametrically. Goodness-of-fit tests are presented for formally evaluating the parametric models. Both estimators perform well with moderate sample sizes in simulation studies. The practical use of the methodology is illustrated in an analysis of dementia associations.

  18. Multifocal Electroretinography after High Dose Chloroquine Therapy for Malaria

    Directory of Open Access Journals (Sweden)

    Aline Correa de Carvalho

    2013-01-01

    Full Text Available Purpose: To investigate changes in multifocal electroretinography (mfERG parameters associated with high dose chloroquine therapy for treatment of malaria in the Amazonia region of Brazil. Methods: Forty-eight subjects who had received chloroquine treatment for single or multiple malaria infections with a cumulative dose ranging from 1,050 to 27,000mg were included. The control group consisted of 37 healthy aged-matched subjects. Data was collected on amplitude and implicit time of the N1, P1 and N2 waves in the central macular hexagon (R1 and in five concentric rings at different retinal eccentricities (R2-R6. Results: No significant difference was observed in any mfERG parameter between chloroquine treated patients and control subjects. A comparison with previous data obtained from patients with rheumatologic disorders in the same region of Brazil who had received larger cumulative doses of chloroquine and had displayed mfERG changes, indicated that retinal toxicity seems to be dependent on cumulative dose. Conclusion: Lack of mfERG changes in the current study suggests that intensive high dose chloroquine therapy for treatment of malaria is not associated with retinal toxicity.

  19. Patient exposure: description of cumulative irradiation of patients treated in interventional cardiology; Exposition des patients: description de l'irradiation cumulee des patients traites en cardiologie interventionnelle

    Energy Technology Data Exchange (ETDEWEB)

    Odile Bernier, M.O. [Institut de Radioprotection et de Surete Nucleaire, Laboratoire d ' Epidemiologie, 92 - Fontenay aux Roses (France)

    2009-07-01

    Despite its clinical benefits, interventional cardiology induces cumulative exposure to ionizing radiation and may entail an important irradiation of the patient at the cutaneous level as well as for organs at the vicinity of the heart. The author briefly reports a study performed on a sample of 1591 patients who have been submitted to at least one corono-graphy or one angioplasty during 2005. Based on clinical characteristics and dose-area-product measurements, the doses received by lung, oesophagus, bone medulla and breast have been computed

  20. County-level cumulative environmental quality associated with cancer incidence.

    Science.gov (United States)

    Jagai, Jyotsna S; Messer, Lynne C; Rappazzo, Kristen M; Gray, Christine L; Grabich, Shannon C; Lobdell, Danelle T

    2017-08-01

    Individual environmental exposures are associated with cancer development; however, environmental exposures occur simultaneously. The Environmental Quality Index (EQI) is a county-level measure of cumulative environmental exposures that occur in 5 domains. The EQI was linked to county-level annual age-adjusted cancer incidence rates from the Surveillance, Epidemiology, and End Results (SEER) Program state cancer profiles. All-site cancer and the top 3 site-specific cancers for male and female subjects were considered. Incident rate differences (IRDs; annual rate difference per 100,000 persons) and 95% confidence intervals (CIs) were estimated using fixed-slope, random intercept multilevel linear regression models. Associations were assessed with domain-specific indices and analyses were stratified by rural/urban status. Comparing the highest quintile/poorest environmental quality with the lowest quintile/best environmental quality for overall EQI, all-site county-level cancer incidence rate was positively associated with poor environmental quality overall (IRD, 38.55; 95% CI, 29.57-47.53) and for male (IRD, 32.60; 95% CI, 16.28-48.91) and female (IRD, 30.34; 95% CI, 20.47-40.21) subjects, indicating a potential increase in cancer incidence with decreasing environmental quality. Rural/urban stratified models demonstrated positive associations comparing the highest with the lowest quintiles for all strata, except the thinly populated/rural stratum and in the metropolitan/urbanized stratum. Prostate and breast cancer demonstrated the strongest positive associations with poor environmental quality. We observed strong positive associations between the EQI and all-site cancer incidence rates, and associations differed by rural/urban status and environmental domain. Research focusing on single environmental exposures in cancer development may not address the broader environmental context in which cancers develop, and future research should address cumulative environmental

  1. Economic and policy implications of the cumulative carbon budget

    Science.gov (United States)

    Allen, M. R.; Otto, F. E. L.; Otto, A.; Hepburn, C.

    2014-12-01

    The importance of cumulative carbon emissions in determining long-term risks of climate change presents considerable challenges to policy makers. The traditional notion of "total CO2-equivalent emissions", which forms the backbone of agreements such as the Kyoto Protocol and the European Emissions Trading System, is fundamentally flawed. Measures to reduce short-lived climate pollutants benefit the current generation, while measures to reduce long-lived climate pollutants benefit future generations, so there is no sense in which they can ever be considered equivalent. Debates over the correct metric used to compute CO2-equivalence are thus entirely moot: both long-lived and short-lived emissions will need to be addressed if all generations are to be protected from dangerous climate change. As far as long-lived climate pollutants are concerned, the latest IPCC report highlights the overwhelming importance of carbon capture and storage in determining the cost of meeting the goal of limiting anthropogenic warming to two degrees. We will show that this importance arises directly from the cumulative carbon budget and the role of CCS as the technology of last resort before economic activity needs to be restricted to meet ambitious climate targets. It highlights the need to increase the rate of CCS deployment by orders of magnitude if the option of avoiding two degrees is to be retained. The difficulty of achieving this speed of deployment through conventional incentives and carbon-pricing mechanisms suggests a need for a much more direct mandatory approach. Despite their theoretical economic inefficiency, the success of recent regulatory measures in achieving greenhouse gas emissions reductions in jurisdictions such as the United States suggests an extension of the regulatory approach could be a more effective and politically acceptable means of achieving adequately rapid CCS deployment than conventional carbon taxes or cap-and-trade systems.

  2. Fast motion-including dose error reconstruction for VMAT with and without MLC tracking

    DEFF Research Database (Denmark)

    Ravkilde, Thomas; Keall, Paul J.; Grau, Cai

    2014-01-01

    of the algorithm for reconstruction of dose and motion-induced dose errors throughout the tracking and non-tracking beam deliveries was quantified. Doses were reconstructed with a mean dose difference relative to the measurements of -0.5% (5.5% standard deviation) for cumulative dose. More importantly, the root......-mean-square deviation between reconstructed and measured motion-induced 3%/3 mm γ failure rates (dose error) was 2.6%. The mean computation time for each calculation of dose and dose error was 295 ms. The motion-including dose reconstruction allows accurate temporal and spatial pinpointing of errors in absorbed dose...... validate a simple model for fast motion-including dose error reconstruction applicable to intrafractional QA of MLC tracking treatments of moving targets. MLC tracking experiments were performed on a standard linear accelerator with prototype MLC tracking software guided by an electromagnetic transponder...

  3. Thermal momentum distribution from path integrals with shifted boundary conditions

    CERN Document Server

    Giusti, Leonardo

    2011-01-01

    For a thermal field theory formulated in the grand canonical ensemble, the distribution of the total momentum is an observable characterizing the thermal state. We show that its cumulants are related to thermodynamic potentials. In a relativistic system for instance, the thermal variance of the total momentum is a direct measure of the enthalpy. We relate the generating function of the cumulants to the ratio of (a) a partition function expressed as a Matsubara path integral with shifted boundary conditions in the compact direction, and (b) the ordinary partition function. In this form the generating function is well suited for Monte-Carlo evaluation, and the cumulants can be extracted straightforwardly. We test the method in the SU(3) Yang-Mills theory and obtain the entropy density at three different temperatures.

  4. Dose estimation for repeated phosphorus-32 ingestion in human subjects

    Energy Technology Data Exchange (ETDEWEB)

    Chao, J.H.; Tseng, C.L.; Hsieh, W.A.; Hung, D.Z.; Chang, W.P. E-mail: wpc94@mailsrv.ym.edu.tw

    2001-01-15

    Dose estimation was conducted for internal phosphorus-32 exposure in one young male subject from repeated oral mis-ingestion for >1 year. Since disclosure for previous continuous contamination, a series of urine samples were collected from this individual weekly for a period of >2 months. P-32 radioactivity in urine samples were measured by the acid precipitation method. Estimation for retrospective total effective dose equivalent received by this subject was conducted for cumulative internal dose estimation. A minimum of 9.4 mSv was estimated for an assumed single ingestion. As this was a rare case in radiation protection and internal radiation dosimetry, its implications were of considerable significance.

  5. Cumulative Interarrival Time Distributions of Freeway Entrance Ramp Traffic for Traffic Simulations

    Directory of Open Access Journals (Sweden)

    Erdinç Öner

    2013-02-01

    Full Text Available Cumulative interarrival time (IAT distributions for signalized and non-signalized freeway entrance ramps were developed to be used in digital computer traffic simulation models. The data from four different non-signalized entrance ramps (three ramps with a single lane, one ramp with two lanes and two different signalized entrance ramps (both with a single lane were used for developing the cumulative IAT distributions. The cumulative IAT distributions for the signalized and non-signalized entrance ramps were compared with each other and with the cumulative IAT distributions of the lanes for freeways. The comparative results showed that the cumulative IAT distributions for non-signalized entrance ramps are very close to the leftmost lane of a 3-lane freeway where the maximum absolute difference between the cumulative IAT distribution of the leftmost lane of a 3-lane freeway and the entrance ramps cumulative IAT distribution was 3%. The cumulative IAT distribution for the signalized entrance ramps was found to be different from the non-signalized entrance ramp cumulative IAT distribution. The approximated cumulative IAT distributions for signalized and non-signalized entrance ramp traffic for any hourly traffic volume from a few vehicles/hour up to 2,500 vehicles/hour can be obtained at http://www.ohio.edu/orite/research/uitds.cfm.

  6. Probabilistic fracture mechanics analysis of thermally aged nuclear piping in a pressurized water reactor

    Energy Technology Data Exchange (ETDEWEB)

    Li, Shuxiao; Zhang, Hailong; Li, Shilei; Wang, Yanli [State Key Laboratory for Advanced Metals and Materials, University of Science and Technology Beijing, Beijing 100083 (China); Xue, Fei [Suzhou Nuclear Power Research Institute, Suzhou 215004 (China); Wang, Xitao, E-mail: xtwang@ustb.edu.cn [State Key Laboratory for Advanced Metals and Materials, University of Science and Technology Beijing, Beijing 100083 (China)

    2013-12-15

    Highlights: • Thermal aging embrittlement was considered in the PFM analysis of nuclear pipe. • Predicting program for pipe failure probability was developed based on thermal aging. • Cumulative failure probability is significantly affected by fracture toughness. • Cumulative failure probability is slightly affected by fatigue crack growth rate. • Tensile strength increase due to thermal aging slightly reduces pipe failure risk. - Abstract: A predicting program for pipe break probability based on thermal aging embrittlement was developed. In order for life prediction, evolutions of fracture toughness and tensile strength were estimated for a Z3CN20-09M piping steel using the Argonne National Laboratory (ANL) procedure. To understand the influence of thermal aging on failure probability, different evolutions of fracture toughness, tensile strength and fatigue crack growth rate were employed in the prediction of cumulative failure probability. The results show that the cumulative failure probability for 40-year thermal aging increases by almost four times compared to without consideration of fracture toughness degradation. The cumulative failure probability is slightly affected by fatigue crack growth rate. The increase of tensile strength due to thermal aging reduces the risk of pipe failure. This work demonstrates that the degradation of fracture toughness due to thermal aging should be fully considered in the probabilistic fracture mechanics analysis of nuclear pressure pipes.

  7. Using Physiologically-Based Pharmacokinetic Models to Incorporate Chemical and Non-Chemical Stressors into Cumulative Risk Assessment: A Case Study of Pesticide Exposures

    Directory of Open Access Journals (Sweden)

    Jonathan I. Levy

    2012-05-01

    Full Text Available Cumulative risk assessment has been proposed as an approach to evaluate the health risks associated with simultaneous exposure to multiple chemical and non-chemical stressors. Physiologically based pharmacokinetic/pharmacodynamic (PBPK/PD models can allow for the inclusion and evaluation of multiple stressors, including non-chemical stressors, but studies have not leveraged PBPK/PD models to jointly consider these disparate exposures in a cumulative risk context. In this study, we focused on exposures to organophosphate (OP pesticides for children in urban low-income environments, where these children would be simultaneously exposed to other pesticides (including pyrethroids and non-chemical stressors that may modify the effects of these exposures (including diet. We developed a methodological framework to evaluate chemical and non-chemical stressor impacts on OPs, utilizing an existing PBPK/PD model for chlorpyrifos. We evaluated population-specific stressors that would influence OP doses or acetylcholinesterase (AChE inhibition, the relevant PD outcome. We incorporated the impact of simultaneous exposure to pyrethroids and dietary factors on OP dose through the compartments of metabolism and PD outcome within the PBPK model, and simulated combinations of stressors across multiple exposure ranges and potential body weights. Our analyses demonstrated that both chemical and non-chemical stressors can influence the health implications of OP exposures, with up to 5-fold variability in AChE inhibition across combinations of stressor values for a given OP dose. We demonstrate an approach for modeling OP risks in the presence of other population-specific environmental stressors, providing insight about co-exposures and variability factors that most impact OP health risks and contribute to children’s cumulative health risk from pesticides. More generally, this framework can be used to inform cumulative risk assessment for any compound impacted by

  8. The cumulative analgesic effect of repeated electroacupuncture involves synaptic remodeling in the hippocampal CA3 region

    Institute of Scientific and Technical Information of China (English)

    Qiuling Xu; Tao Liu; Shuping Chen; Yonghui Gao; Junying Wang; Lina Qiao; Junling Liu

    2012-01-01

    In the present study, we examined the analgesic effect of repeated electroacupuncture at bilateral Zusanli (ST36) and Yanglingquan (GB34) once a day for 14 consecutive days in a rat model of chronic sciatic nerve constriction injury-induced neuropathic pain. In addition, concomitant changes in calcium/calmodulin-dependent protein kinase II expression and synaptic ultrastructure of neurons in the hippocampal CA3 region were examined. The thermal pain threshold (paw withdrawal latency) was increased significantly in both groups at 2 weeks after electroacupuncture intervention compared with 2 days of electroacupuncture. In ovariectomized rats with chronic constriction injury, the analgesic effect was significantly reduced. Electroacupuncture for 2 weeks significantly diminished the injury-induced increase in synaptic cleft width and thinning of the postsynaptic density, and it significantly suppressed the down-regulation of intracellular calcium/ calmodulin-dependent protein kinase II expression in the hippocampal CA3 region. Repeated electroacupuncture intervention had a cumulative analgesic effect on injury-induced neuropathic pain reactions, and it led to synaptic remodeling of hippocampal neurons and upregulated calcium/calmodulin-dependent protein kinase II expression in the hippocampal CA3 region.

  9. Sensitivity Tests for Cumulative Damage Function (CDF) for the PGSFR

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Chiwoong; Ha, Kwiseok [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2014-10-15

    A safety analysis including the design basis and beyond design basis events has been conducted using MARS-LMR. Previous safety limits were based on temperature and the duration time. However, the cumulative damage function (CDF) will be used as the safety limit to evaluate the fuel cladding integrity. Recently, a 4S reactor developed by Toshiba used the same approach for a safety analysis. Therefore, the development a CDF is necessary to evaluate the safety limit for the PGSFR safety analyses. The major keys in the CDF model are behavior of fuel and cladding. It is not easy to obtain a metallic fuel database for a CDF model including the cladding materials. Argonne National Laboratory (ANL) in the United States is the only major leading group for metallic fuel experiments. They conducted various experiments with various facilities and experimental reactors, for example, EBR-II, FFTF, and TREAT. In addition, they have recently been trying to extend their oxide fuel based a severe accident code, SAS4A/SASSYS, to a metallic fuel version using their metallic fuel database. In this study, the preliminary CDF model was supplemented in the MARS-LMR code. The major source was the SAS4A/SASSYS modules related to fuel and cladding transient behaviors.. In addition, a sensitivity test for some parameters in the CDF model was conducted to evaluate the capability of these models and to find the major parameter of fuel failure. The Cumulative Damage Function is a good indicator for a fuel failure. The major parameters for the CDF model are selected including cladding and fuel temperatures, initial pressure and volume in the gas plenum, clad thickness, and fission power in the fuel pin. The most sensitive parameter is the cladding temperature. Also, cladding thickness and gas pressure in the fuel pin are effective parameters on the CDF. During an actual transient, various parameter including sensitivity test parameters in this study will be changed simultaneously. This study can

  10. Cumulative risk assessment for plasticizer-contaminated food using the hazard index approach.

    Science.gov (United States)

    Chang, J W; Chen, C Y; Yan, B R; Chang, M H; Tseng, S H; Kao, Y M; Chen, J C; Lee, C C

    2014-06-01

    Phthalates strongly and adversely affect reproduction, development and liver function. We did a cumulative risk assessment for simultaneous exposure to nine phthalates using the hazard index (HI) and the levels of nine phthalates in 1200 foodstuff samples. DEHP (di-2-ethylhexyl phthalate) present the highest level (mean: 0.443 mg/kg) in 1200 samples, and the highest average daily dose (ADD) was found in DEHP, ΣDBP(i + n) (the sum of dibutyl phthalate [DBP] isomers [DnBP + DiBP]) posed the highest risk potential of all the phthalates. In seven phthalates, the 95th percentiles of the ADDs for ΣDBP(i + n) in 0-6-yr-old children accounted for 91% (79-107%) of the tolerable daily intake, and the 95th percentiles of the HIs for the anti-androgenic effects of five phthalates in 0-3-yr-old children and 4-6-yr-old girls were >1. We conclude that the health of younger Taiwanese may be adversely affected by overexposure of phthalate-contaminated foods.

  11. Anti-irritants II: Efficacy against cumulative irritation

    DEFF Research Database (Denmark)

    Andersen, Flemming; Hedegaard, Kathryn; Petersen, Thomas Kongstad

    2006-01-01

    of 4 alleged AI (nifedipine, (-)-alpha-bisabolol, canola oil and glycerol) was studied on experimentally induced acute irritation in healthy volunteers, and only glycerol showed dose-related response and effects potentially better than no treatment. The acute irritation model only allowed a small...

  12. Existence of Solutions of a Riccati Differential System from a General Cumulant Control Problem

    Directory of Open Access Journals (Sweden)

    Stanley R. Liberty

    2011-01-01

    Full Text Available We study a system of infinitely many Riccati equations that arise from a cumulant control problem, which is a generalization of regulator problems, risk-sensitive controls, minimal cost variance controls, and k-cumulant controls. We obtain estimates for the existence intervals of solutions of the system. In particular, new existence conditions are derived for solutions on the horizon of the cumulant control problem.

  13. Pediatric patient doses in interventional cardiology procedures; Doses em paciente pediatrico em procedimentos de cardiologia intervencionista

    Energy Technology Data Exchange (ETDEWEB)

    Medeiros, R.B.; Murata, C.H.; Moreira, A.C., E-mail: rbitelli2012@gmail.com, E-mail: camila.murata@gmail.com, E-mail: antonio.xray@gmail.com [Universidade Federal de Sao Paulo (UNIFESP), Sao Paulo, SP (Brazil). Escola Pulista de Medicina; Khoury, H.J.; Borras, C., E-mail: hjkhoury@gmail.com, E-mail: cariborras@starpower.net [Universidade Federal de Pernambuco (DEN/UFPE), Recife, PE (Brazil). Dept. de Engenharia Nuclear; Silva, M.S.R da, E-mail: msrochas2003@yahoo.com.br [Instituto Federal de Educacao, Ciencia e Tecnologia de Pernambuco (IFPE), Recife, PE (Brazil)

    2014-07-01

    The radiation doses from interventional procedures is relevant when treating children because of their greater radiosensitivity compared with adults. The purposes of this paper were to estimate the dose received by 18 pediatric patients who underwent cardiac interventional procedures and to correlate the maximum entrance surface air kerma (Ke,max), estimated with radiochromic films, with the cumulative air kerma values displayed at the end of procedures. This study was performed in children up to 6 years. The study was performed in two hospitals, one located in Recife and the other one in São Paulo. The x-ray imaging systems used were Phillips Allura 12 model with image intensifier system and a Phillips Allura FD10 flat panel system. To estimate the Ke,max on the patient’s skin radiochromic films(Gafchromic XR-RV2) were used. These values were estimated from the maximum optical density measured on film using a calibration curve. The results showed cumulative air kerma values ranging from 78.3- 500.0mGy, with a mean value of 242,3 mGy. The resulting Ke,max values ranged from 20.0-461.8 mGy, with a mean value of 208,8 mGy. The Ke,max values were correlated with the displayed cumulative air kerma values. The correlation factor R² was 0.78, meaning that the value displayed in the equipment’s console can be useful for monitoring the skin absorbed dose throughout the procedure. The routine fluoroscopy time records is not able by itself alert the physician about the risk of dose exceeding the threshold of adverse reactions, which can vary from an early erythema to serious harmful skin damage. (author)

  14. Scenario dependency of the transient climate response to cumulative emissions

    Science.gov (United States)

    Turner, Katherine; Williams, Ric; Oschlies, Andreas

    2017-04-01

    The transient climate response to emissions (TCRE), in relating surface temperature changes to cumulative carbon emissions, provides a means of estimating carbon budgets from global warming benchmarks. Current Earth System Model results indicate that the TCRE is linear and scenario-independent. We explore the sensitivity of the TCRE to scenario and model parameter uncertainties using 8 configurations of the UVic Earth System Model of Intermediate Complexity, forced by 2 twenty-first-century emissions scenarios (RCP 4.5 and 8.5). We find that the TCRE is higher under RCP 4.5 than 8.5 by 0.3-0.8 K/1000 Pg C and shows opposing nonlinear tendencies in these scenarios: an increase of 0.15-0.5 K/1000 Pg C over RCP 4.5 and a decrease of 0-0.7 K/1000 Pg C over RCP 8.5. These differences are robust across model configurations with perturbed land and ocean parametrizations and are the result of the decreased efficiency of heat transport into the deep ocean under decelerating emissions.

  15. High selection pressure promotes increase in cumulative adaptive culture.

    Directory of Open Access Journals (Sweden)

    Carolin Vegvari

    Full Text Available The evolution of cumulative adaptive culture has received widespread interest in recent years, especially the factors promoting its occurrence. Current evolutionary models suggest that an increase in population size may lead to an increase in cultural complexity via a higher rate of cultural transmission and innovation. However, relatively little attention has been paid to the role of natural selection in the evolution of cultural complexity. Here we use an agent-based simulation model to demonstrate that high selection pressure in the form of resource pressure promotes the accumulation of adaptive culture in spite of small population sizes and high innovation costs. We argue that the interaction of demography and selection is important, and that neither can be considered in isolation. We predict that an increase in cultural complexity is most likely to occur under conditions of population pressure relative to resource availability. Our model may help to explain why culture change can occur without major environmental change. We suggest that understanding the interaction between shifting selective pressures and demography is essential for explaining the evolution of cultural complexity.

  16. INTERACTIVE VISUALIZATION OF PROBABILITY AND CUMULATIVE DENSITY FUNCTIONS

    KAUST Repository

    Potter, Kristin

    2012-01-01

    The probability density function (PDF), and its corresponding cumulative density function (CDF), provide direct statistical insight into the characterization of a random process or field. Typically displayed as a histogram, one can infer probabilities of the occurrence of particular events. When examining a field over some two-dimensional domain in which at each point a PDF of the function values is available, it is challenging to assess the global (stochastic) features present within the field. In this paper, we present a visualization system that allows the user to examine two-dimensional data sets in which PDF (or CDF) information is available at any position within the domain. The tool provides a contour display showing the normed difference between the PDFs and an ansatz PDF selected by the user and, furthermore, allows the user to interactively examine the PDF at any particular position. Canonical examples of the tool are provided to help guide the reader into the mapping of stochastic information to visual cues along with a description of the use of the tool for examining data generated from an uncertainty quantification exercise accomplished within the field of electrophysiology.

  17. Model-checking techniques based on cumulative residuals.

    Science.gov (United States)

    Lin, D Y; Wei, L J; Ying, Z

    2002-03-01

    Residuals have long been used for graphical and numerical examinations of the adequacy of regression models. Conventional residual analysis based on the plots of raw residuals or their smoothed curves is highly subjective, whereas most numerical goodness-of-fit tests provide little information about the nature of model misspecification. In this paper, we develop objective and informative model-checking techniques by taking the cumulative sums of residuals over certain coordinates (e.g., covariates or fitted values) or by considering some related aggregates of residuals, such as moving sums and moving averages. For a variety of statistical models and data structures, including generalized linear models with independent or dependent observations, the distributions of these stochastic processes tinder the assumed model can be approximated by the distributions of certain zero-mean Gaussian processes whose realizations can be easily generated by computer simulation. Each observed process can then be compared, both graphically and numerically, with a number of realizations from the Gaussian process. Such comparisons enable one to assess objectively whether a trend seen in a residual plot reflects model misspecification or natural variation. The proposed techniques are particularly useful in checking the functional form of a covariate and the link function. Illustrations with several medical studies are provided.

  18. Microcanonical thermostatistics analysis without histograms: cumulative distribution and Bayesian approaches

    CERN Document Server

    Alves, Nelson A; Rizzi, Leandro G

    2015-01-01

    Microcanonical thermostatistics analysis has become an important tool to reveal essential aspects of phase transitions in complex systems. An efficient way to estimate the microcanonical inverse temperature $\\beta(E)$ and the microcanonical entropy $S(E)$ is achieved with the statistical temperature weighted histogram analysis method (ST-WHAM). The strength of this method lies on its flexibility, as it can be used to analyse data produced by algorithms with generalised sampling weights. However, for any sampling weight, ST-WHAM requires the calculation of derivatives of energy histograms $H(E)$, which leads to non-trivial and tedious binning tasks for models with continuous energy spectrum such as those for biomolecular and colloidal systems. Here, we discuss two alternative methods that avoid the need for such energy binning to obtain continuous estimates for $H(E)$ in order to evaluate $\\beta(E)$ by using ST-WHAM: (i) a series expansion to estimate probability densities from the empirical cumulative distrib...

  19. Cumulative sum quality control for calibrated breast density measurements

    Energy Technology Data Exchange (ETDEWEB)

    Heine, John J.; Cao Ke; Beam, Craig [Cancer Prevention and Control Division, Moffitt Cancer Center, 12902 Magnolia Drive, Tampa, Florida 33612 (United States); Division of Epidemiology and Biostatistics, School of Public Health, University of Illinois at Chicago, 1603 W. Taylor St., Chicago, Illinois 60612 (United States)

    2009-12-15

    Purpose: Breast density is a significant breast cancer risk factor. Although various methods are used to estimate breast density, there is no standard measurement for this important factor. The authors are developing a breast density standardization method for use in full field digital mammography (FFDM). The approach calibrates for interpatient acquisition technique differences. The calibration produces a normalized breast density pixel value scale. The method relies on first generating a baseline (BL) calibration dataset, which required extensive phantom imaging. Standardizing prospective mammograms with calibration data generated in the past could introduce unanticipated error in the standardized output if the calibration dataset is no longer valid. Methods: Sample points from the BL calibration dataset were imaged approximately biweekly over an extended timeframe. These serial samples were used to evaluate the BL dataset reproducibility and quantify the serial calibration accuracy. The cumulative sum (Cusum) quality control method was used to evaluate the serial sampling. Results: There is considerable drift in the serial sample points from the BL calibration dataset that is x-ray beam dependent. Systematic deviation from the BL dataset caused significant calibration errors. This system drift was not captured with routine system quality control measures. Cusum analysis indicated that the drift is a sign of system wear and eventual x-ray tube failure. Conclusions: The BL calibration dataset must be monitored and periodically updated, when necessary, to account for sustained system variations to maintain the calibration accuracy.

  20. Enhanced cumulative sum charts for monitoring process dispersion.

    Science.gov (United States)

    Abujiya, Mu'azu Ramat; Riaz, Muhammad; Lee, Muhammad Hisyam

    2015-01-01

    The cumulative sum (CUSUM) control chart is widely used in industry for the detection of small and moderate shifts in process location and dispersion. For efficient monitoring of process variability, we present several CUSUM control charts for monitoring changes in standard deviation of a normal process. The newly developed control charts based on well-structured sampling techniques - extreme ranked set sampling, extreme double ranked set sampling and double extreme ranked set sampling, have significantly enhanced CUSUM chart ability to detect a wide range of shifts in process variability. The relative performances of the proposed CUSUM scale charts are evaluated in terms of the average run length (ARL) and standard deviation of run length, for point shift in variability. Moreover, for overall performance, we implore the use of the average ratio ARL and average extra quadratic loss. A comparison of the proposed CUSUM control charts with the classical CUSUM R chart, the classical CUSUM S chart, the fast initial response (FIR) CUSUM R chart, the FIR CUSUM S chart, the ranked set sampling (RSS) based CUSUM R chart and the RSS based CUSUM S chart, among others, are presented. An illustrative example using real dataset is given to demonstrate the practicability of the application of the proposed schemes.

  1. Detection of abrupt baseline length changes using cumulative sums

    Science.gov (United States)

    Janssen, Volker

    2009-06-01

    Dynamic processes are usually monitored by collecting a time series of observations, which is then analysed in order to detect any motion or non-standard behaviour. Geodetic examples include the monitoring of dams, bridges, high-rise buildings, landslides, volcanoes and tectonic motion. The cumulative sum (CUSUM) test is recognised as a popular means to detect changes in the mean and/or the standard deviation of a time series and has been applied to various monitoring tasks. This paper briefly describes the CUSUM technique and how it can be utilised for the detection of small baseline length changes by differencing two perpendicular baselines sharing a common site. A simulation is carried out in order to investigate the expected behaviour of the resulting CUSUM charts for a variety of typical deformation monitoring scenarios. This simulation shows that using first differences (between successive epochs) as input, rather than the original baseline lengths, produces clear peaks or jumps in the differenced CUSUM time series when a sudden change in baseline length occurs. These findings are validated by analysing several GPS baseline pairs of a network deployed to monitor the propagation of an active ice shelf rift on the Amery Ice Shelf, East Antarctica.

  2. Estimation of cumulative cadmium intake causing Itai-itai disease.

    Science.gov (United States)

    Inaba, Takeya; Kobayashi, Etsuko; Suwazono, Yasushi; Uetani, Mirei; Oishi, Mitsuhiro; Nakagawa, Hideaki; Nogawa, Koji

    2005-11-15

    This study was undertaken to estimate the amount of cadmium (Cd) exposure needed for the development of Itai-itai disease. The investigated subjects comprised 82 Itai-itai disease patients and 11 persons requiring observation who were admitted in 1977 and 1978 for medical testing. With the period when the Itai-itai disease patients started to perceive leg/back pain defined as the 'mild disease onset', and the period when they experienced the most severe manifestations such as ambulatory disturbance and bone fractures defined as 'severe disease onset'. Relative cumulative person number distribution according to life time cadmium intake (LCD) at mild disease onset, severe disease onset, and time of death was depicted as an sigmoid curve and the establishment of probit regression lines was demonstrated between them. LCD at the time when mild disease onset and severe disease onset were recognized in half of the Itai-itai disease patients was 3.1 and 3.8 g, respectively. Furthermore, LCD at the time when mild disease onset and severe disease onset were recognized in 5% of the Itai-itai disease patients was calculated to be 2.6 and 3.3 g, respectively. The present results clarify that Itai-itai disease, the most severe stage of chronic Cd poisoning, occurs at levels of Cd consumption amounting to approximately three-fold of those currently seen in Japan.

  3. LINGUISTIC DETERMINISM, CUMULATIVE EVOLUTION AND DEVELOPMENT OF SCIENTIFIC KNOWLEDGE

    Directory of Open Access Journals (Sweden)

    Sukhoverkhov A. V.

    2015-01-01

    Full Text Available The main purpose of this study is to examine how language and its historically inherited content and structure allows accumulating knowledge and determines the development of the individuals, culture and science. The article shows the theoretical drawbacks of modern "pragmatic turn" in which language is depicted only as a derivate of natural, cultural and cognitive systems. Instead, it is stated that language, in addition to all of the above, have to be considered also as a relatively independent basis and one of the causes that determine individual and social development. For that reason, the study examines the system nature of language, thought and culture, their environmental and social "embeddiness", a close relationship with other sign systems and with various forms of social activities. From that point, theoretical reduction of multiple relations and varying causes in complex ecological and social systems only to bilateral relations of language-thought, language-culture are revised. Particular attention is paid to the role of language in the accumulation and systematization of scientific knowledge and the transmission of cultural traditions. In that context, language is seen as part of the non-genetic inheritance systems, "social a priori" that determines the content and creates conditions for cumulative social evolution. Therefore, it is maintained that the comprehensive studies of language and its significance for culture and science have to embrace within a systems approach both the linguistic and pragmatic "turns"

  4. Simulation of the cumulative hydrological response to green infrastructure

    Science.gov (United States)

    Avellaneda, P. M.; Jefferson, A. J.; Grieser, J. M.; Bush, S. A.

    2017-04-01

    In this study, we evaluated the cumulative hydrologic performance of green infrastructure in a residential area of the city of Parma, Ohio, draining to a tributary of the Cuyahoga River. Green infrastructure included the following spatially distributed devices: 16 street-side bioretention cells, 7 rain gardens, and 37 rain barrels. Data consisted of rainfall and outfall flow records for a wide range of storm events, including pretreatment and treatment periods. The Stormwater Management Model was calibrated and validated to predict the hydrologic response of green infrastructure. The calibrated model was used to quantify annual water budget alterations and discharge frequency over a 6 year simulation period. For the study catchment, we observed a treatment effect with increases of 1.4% in evaporation, 7.6% in infiltration, and a 9.0% reduction in surface runoff. The hydrologic performance of green infrastructure was evaluated by comparing the flow duration curve for pretreatment and treatment outfall flow scenarios. The flow duration curve shifted downward for the green infrastructure scenario. Discharges with a 0.5, 1, 2, and 5 year return period were reduced by an average of 29%. Parameter and predictive uncertainties were inspected by implementing a Bayesian statistical approach.

  5. A New Tool for Seismology--the Cumulative Spectral Power

    CERN Document Server

    Peters, Randall D

    2007-01-01

    The power spectral density (PSD) function is commonly used to specify seismometer performance. It is derived from the FFT of acceleration and correction is made for the transfer function of the instrument that generated the data. As with any such spectrum of density (`per Hz') type, the noise inherent to a PSD is large. This article illustrates the value of a function that is derived from the PSD and for which the influence of noise is significantly reduced. Called the cumulative spectral power (CSP), it is obtained from the PSD through the noise-reducing process of integration. The maximum of the CSP (corresponding to the longest graphed value of the period) provides a means for estimating the total vibrational power of the earth. The present author has significantly simplified the process of PSD generation. Thus routine graphing is straightforwared-of first the FFT, followed by the generation of both a PSD and its associated CSP. The unique properties of the CSP make it valuable for the study of a variety o...

  6. A shock process with a non-cumulative damage

    Energy Technology Data Exchange (ETDEWEB)

    Finkelstein, M.S.; Zarudnij, V.I

    2001-01-01

    Two types of non-cumulative damage shock models are considered. Based on the distribution of damage, caused by a shock effecting a system, the intervals with small, intermediate and large damage are introduced. The initial homogeneous Poisson shock process is split into three homogeneous Poisson processes and studied independently. Several criteria of failure are considered, based on the assumption that shocks with a small level of damage are harmless for a system, shocks with a large level of damage results in the system's failure and shocks with an intermediate level of damage can result in the system's failure only with some probability. The second model is based on an assumption that shocks with a small level of damage are harmless to a system, if they are not too close to each other. The probability of the system's failure-free performance in [0,t) is derived explicitly. Simple asymptotic exponential approximations are obtained The accuracy of this method is analyzed. Possible generalizations are discussed.

  7. Cumulative signal transmission in nonlinear reaction-diffusion networks.

    Directory of Open Access Journals (Sweden)

    Diego A Oyarzún

    Full Text Available Quantifying signal transmission in biochemical systems is key to uncover the mechanisms that cells use to control their responses to environmental stimuli. In this work we use the time-integral of chemical species as a measure of a network's ability to cumulatively transmit signals encoded in spatiotemporal concentrations. We identify a class of nonlinear reaction-diffusion networks in which the time-integrals of some species can be computed analytically. The derived time-integrals do not require knowledge of the solution of the reaction-diffusion equation, and we provide a simple graphical test to check if a given network belongs to the proposed class. The formulae for the time-integrals reveal how the kinetic parameters shape signal transmission in a network under spatiotemporal stimuli. We use these to show that a canonical complex-formation mechanism behaves as a spatial low-pass filter, the bandwidth of which is inversely proportional to the diffusion length of the ligand.

  8. New tests of cumulative prospect theory and the priority heuristic

    Directory of Open Access Journals (Sweden)

    Michael H. Birnbaum

    2008-04-01

    Full Text Available Previous tests of cumulative prospect theory (CPT and of the priority heuristic (PH found evidence contradicting these two models of risky decision making. However, those tests were criticized because they had characteristics that might ``trigger'' use of other heuristics. This paper presents new tests that avoid those characteristics. Expected values of the gambles are nearly equal in each choice. In addition, if a person followed expected value (EV, expected utility (EU, CPT, or PH in these tests, she would shift her preferences in the same direction as shifts in EV or EU. In contrast, the transfer of attention exchange model (TAX and a similarity model predict that people will reverse preferences in the opposite direction. Results contradict the PH, even when PH is modified to include a preliminary similarity evaluation using the PH parameters. New tests of probability-consequence interaction were also conducted. Strong interactions were observed, contrary to PH. These results add to the growing bodies of evidence showing that neither CPT nor PH is an accurate description of risky decision making.

  9. Cumulative creep fatigue damage in 316 stainless steel

    Science.gov (United States)

    Mcgaw, Michael A.

    1989-01-01

    The cumulative creep-fatigue damage behavior of 316 stainless steel at 1500 F was experimentally established for the two-level loading cases of fatigue followed by fatigue, creep fatigue followed by fatigue, and fatigue followed by creep fatigue. The two-level loadings were conducted such that the lower life (high strain) cycling was applied first for a controlled number of cycles and the higher life (low strain) cycling was conducted as the second level to failure. The target life levels in this study were 100 cycles to failure for both the fatigue and creep-fatigue lowlife loading, 5000 cycles to failure for the higher life fatigue loading and 10,000 cycles to failure for the higher life creep-fatigue loading. The failed specimens are being examined both fractographically and metallographically to ascertain the nature of the damaging mechanisms that produced failure. Models of creep-fatigue damage accumulation are being evaluated and knowledge of the various damaging mechanisms is necessary to ensure that predictive capability is instilled in the final failure model.

  10. Cumulative biological impacts of The Geysers geothermal development

    Energy Technology Data Exchange (ETDEWEB)

    Brownell, J.A.

    1981-10-01

    The cumulative nature of current and potential future biological impacts from full geothermal development in the steam-dominated portion of The Geysers-Calistoga KGRA are identified by the California Energy Commission staff. Vegetation, wildlife, and aquatic resources information have been reviewed and evaluated. Impacts and their significance are discussed and staff recommendations presented. Development of 3000 MW of electrical energy will result in direct vegetation losses of 2790 acres, based on an estimate of 11.5% loss per lease-hold of 0.93 acres/MW. If unmitigated, losses will be greater. Indirect vegetation losses and damage occur from steam emissions which contain elements (particularly boron) toxic to vegetation. Other potential impacts include chronic low-level boron exposure, acid rain, local climate modification, and mechanical damage. A potential exists for significant reduction and changes in wildlife from direct habitat loss and development influences. Highly erosive soils create the potential for significant reduction of aquatic resources, particularly game fish. Toxic spills have caused some temporary losses of aquatic species. Staff recommends monitoring and implementation of mitigation measures at all geothermal development stages.

  11. Cumulative Causation, Market Transition, and Emigration from China

    Science.gov (United States)

    Liang, Zai; Chunyu, Miao David; Zhuang, Guotu; Ye, Wenzhen

    2009-01-01

    In this paper, we report findings from a recent survey of international migration from China's Fujian province to the United States. We take advantage of the ethnosurvey approach as used in the Mexican Migration Project. Surveys were done in migrant-sending communities in China as well as in destination communities of New York City. We derive hypotheses from two strands of recent studies-the international migration literature and the market transition debate. Our results are in general consistent with hypotheses derived from cumulative causation of migration. However, because of the geographical location of China as compared to Mexico, there are some differences between the two countries in terms of particular migration patterns to the United States. As expected, at the community level, migration prevalence ratio (measuring migration networks) increases the propensity of migration for other members in the community. In contrast, having a household member migrated previously does not increase the propensity of migration of other household members until debt for previous migration is paid off. Our research clearly demonstrates the value of bringing the case of China into the comparative study of international migration. With respect to market transition theory, we find that political power continues to be an important factor in the order of social stratification in the coastal Fujian province. PMID:19569396

  12. The cumulative energy effect for improved ignition timing

    Energy Technology Data Exchange (ETDEWEB)

    Markhotok, A., E-mail: amarhotk@phys.washington.edu [Physics Department, Old Dominion University, Norfolk, Virginia 23529 (United States)

    2015-04-15

    A technique capable of improving timing in ignition applications is proposed. It is based on the use of shock waves propagating in a specific medium that allows achieving extremely high speeds and energies. The model uses the energy cumulation effect in the presence of the shock wave refraction on an interface with plasma. The problem was solved analytically and the effects were demonstrated for a cylindrically symmetrical geometry. Numerical results show very quick and uneven acceleration of different portions of the shock front. Its strong distortions lead to formation of a sharply focused jet near the axis of symmetry. The ability of the shock to achieve extremely high speeds and energies can be useful in design of efficient combustors for hypersonic systems, and possibly offers an alternative way of construction of a nuclear fusion reactor. Recommendations are given in terms of adjustment parameters and can be applied at any problem scale and for various combinations of the strengths of the effects involved in the problem.

  13. Cumulative life course impairment in melanoma and nonmelanoma skin cancer.

    Science.gov (United States)

    Piaserico, Stefano

    2013-01-01

    Patients with skin cancer remain at risk for disease progression or relapse for many years. Therefore, skin cancer may be considered a chronic, life-threatening disease. It could impact on patients lifestyles and social and professional activities. Although no direct study of cumulative life course impairment (CLCI) in skin cancer patients has been carried out, a few studies suggest that skin cancer may strongly impair quality of life and eventually determine a significant CLCI (melanoma more than nonmelanoma skin cancer). Obviously, the life course of patients with melanoma at an advanced stage of the disease may change considerably. A number of cancer-associated problems may determine a CLCI, including familial or professional changes and a reduction of life expectancy may eventually lead to social withdrawal and depressive disorders. Even patients with a low stage disease may experience an important impairment of quality of life and in some cases a CLCI. Some skin cancer patients may have physical and psychological after effects from their cancer surgery. Several patients complain about lymphedema, discomfort experienced from wearing surgical stockings, and diminished range of physical motion postsurgery. A few are concerned about their body image due to surgical scars, and they may consider changing their job position because of the supposed negative impact of scars in visible sites on their ability to perform their job. Some female melanoma survivors may have a reduced desire of having children in the future.

  14. Thermal comfort

    CSIR Research Space (South Africa)

    Osburn, L

    2010-01-01

    Full Text Available Thermal comfort is influenced by environmental parameters as well as other influences including asymmetric heating and cooling conditions. Additionally, some aspects of thermal comfort may be exploited so as to enable a building to operate within a...

  15. Investigation of inconsistent ENDF/B-VII.1 independent and cumulative fission product yields with proposed revisions

    Energy Technology Data Exchange (ETDEWEB)

    Pigni, Marco T [ORNL; Francis, Matthew W [ORNL; Gauld, Ian C [ORNL

    2015-01-01

    A recent implementation of ENDF/B-VII. independent fission product yields and nuclear decay data identified inconsistencies in the data caused by the use of updated nuclear scheme in the decay sub-library that is not reflected in legacy fission product yield data. Recent changes in the decay data sub-library, particularly the delayed neutron branching fractions, result in calculated fission product concentrations that are incompatible with the cumulative fission yields in the library, and also with experimental measurements. A comprehensive set of independent fission product yields was generated for thermal and fission spectrum neutron induced fission for 235,238U and 239,241Pu in order to provide a preliminary assessment of the updated fission product yield data consistency. These updated independent fission product yields were utilized in the ORIGEN code to evaluate the calculated fission product inventories with experimentally measured inventories, with particular attention given to the noble gases. An important outcome of this work is the development of fission product yield covariance data necessary for fission product uncertainty quantification. The evaluation methodology combines a sequential Bayesian method to guarantee consistency between independent and cumulative yields along with the physical constraints on the independent yields. This work was motivated to improve the performance of the ENDF/B-VII.1 library in the case of stable and long-lived cumulative yields due to the inconsistency of ENDF/B-VII.1 fission p;roduct yield and decay data sub-libraries. The revised fission product yields and the new covariance data are proposed as a revision to the fission yield data currently in ENDF/B-VII.1.

  16. Tc-99 m diethylenetriamine-pentaacetic acid (DTPA): is it reliable for assessment of methotrexate-induced cumulative effect on renal filtration in rheumatoid arthritis patients?

    Science.gov (United States)

    Amin, Amr; Effat, Dina; Goher, Nabila; Ramadan, Basma

    2013-12-01

    Methotrexate (MTX) is commonly employed as the initial DMARD used for the treatment of rheumatoid arthritis (RA). We aimed to contribute to the safety profile of MTX by assessing its cumulative effect on renal filtration. A total of 52 RA adult female patients with normal baseline serum creatinine and GFR at the initial diagnosis of the disease were included. Group 1 (G1) included 30 patients (mean age 40.4 ± 4.4 years) on MTX and NSAIDS, while 22 RA patients (mean age 38.5 ± 8.2 years) who received NSAIDs only served as control group (G2). Renal function was assessed by GFR measurement using technetium diethylenetriamine-pentaacetic acid (Tc-99 m DTPA) at a point of the study time corresponding to disease duration. Twenty-one out of thirty (70 %) in G1 showed reduced GFR compared to 6/22 (27.3 %) in G2 (P = 0.007), with 3.3 ± 0.5 % annual reduction in GFR. Reduced GFR in G1 showed significant negative correlation with age (r = -0.396, P = 0.005), MTX cumulative dose (r = -0.263, P = 0.049), MTX-intake duration (r = -0.293, P = 0.031) and NSAIDs-intake duration (r = -0.344, P = 0.014). Low-dose MTX has a slow cumulative effect on renal filtration manifested by GFR reduction overtime that could be monitored by Tc-99 m DTPA.

  17. Cumulative receipt of an anti-poverty tax credit for families did not impact tobacco smoking among parents.

    Science.gov (United States)

    Pega, Frank; Gilsanz, Paola; Kawachi, Ichiro; Wilson, Nick; Blakely, Tony

    2017-04-01

    The effect of anti-poverty tax credit interventions on tobacco consumption is unclear. Previous studies have estimated short-term effects, did not isolate the effects of cumulative dose of tax credits, produced conflicting results, and used methods with limited control for some time-varying confounders (e.g., those affected by prior treatment) and treatment regimen (i.e., study participants' tax credit receipt pattern over time). We estimated the longer-term, cumulative effect of New Zealand's Family Tax Credit (FTC) on tobacco consumption, using a natural experiment (administrative errors leading to exogenous variation in FTC receipt) and methods specifically for controlling confounding, reverse causation, and treatment regimen. We extracted seven waves (2002-2009) of the nationally representative Survey of Family, Income and Employment including 4404 working-age (18-65 years) parents in families. The exposure was the total numbers of years of receiving FTC. The outcomes were regular smoking and the average daily number of cigarettes usually smoked at wave 7. We estimated average treatment effects using inverse probability of treatment weighting and marginal structural modelling. Each additional year of receiving FTC affected neither the odds of regular tobacco smoking among all parents (odds ratio 1.02, 95% confidence interval 0.94-1.11), nor the number of cigarettes smoked among parents who smoked regularly (rate ratio 1.01, 95% confidence interval 0.99-1.03). We found no evidence for an association between the cumulative number of years of receiving an anti-poverty tax credit and tobacco smoking or consumption among parents. The assumptions of marginal structural modelling are quite demanding, and we therefore cannot rule out residual confounding. Nonetheless, our results suggest that tax credit programme participation will not increase tobacco consumption among poor parents, at least in this high-income country. Copyright © 2017 Elsevier Ltd. All rights

  18. Acoustic dose and acoustic dose-rate.

    Science.gov (United States)

    Duck, Francis

    2009-10-01

    Acoustic dose is defined as the energy deposited by absorption of an acoustic wave per unit mass of the medium supporting the wave. Expressions for acoustic dose and acoustic dose-rate are given for plane-wave conditions, including temporal and frequency dependencies of energy deposition. The relationship between the acoustic dose-rate and the resulting temperature increase is explored, as is the relationship between acoustic dose-rate and radiation force. Energy transfer from the wave to the medium by means of acoustic cavitation is considered, and an approach is proposed in principle that could allow cavitation to be included within the proposed definitions of acoustic dose and acoustic dose-rate.

  19. On the duration and intensity of cumulative advantage competitions

    Science.gov (United States)

    Jiang, Bo; Sun, Liyuan; Figueiredo, Daniel R.; Ribeiro, Bruno; Towsley, Don

    2015-11-01

    Network growth can be framed as a competition for edges among nodes in the network. As with various other social and physical systems, skill (fitness) and luck (random chance) act as fundamental forces driving competition dynamics. In the context of networks, cumulative advantage (CA)—the rich-get-richer effect—is seen as a driving principle governing the edge accumulation process. However, competitions coupled with CA exhibit non-trivial behavior and little is formally known about duration and intensity of CA competitions. By isolating two nodes in an ideal CA competition, we provide a mathematical understanding of how CA exacerbates the role of luck in detriment of skill. We show, for instance, that when nodes start with few edges, an early stroke of luck can place the less skilled in the lead for an extremely long period of time, a phenomenon we call ‘struggle of the fittest’. We prove that duration of a simple skill and luck competition model exhibit power-law tails when CA is present, regardless of skill difference, which is in sharp contrast to the exponential tails when fitness is distinct but CA is absent. We also prove that competition intensity is always upper bounded by an exponential tail, irrespective of CA and skills. Thus, CA competitions can be extremely long (infinite mean, depending on fitness ratio) but almost never very intense. The theoretical results are corroborated by extensive numerical simulations. Our findings have important implications to competitions not only among nodes in networks but also in contexts that leverage socio-physical models embodying CA competitions.

  20. Cumulative phase delay imaging - A new contrast enhanced ultrasound modality

    Energy Technology Data Exchange (ETDEWEB)

    Demi, Libertario, E-mail: l.demi@tue.nl; Sloun, Ruud J. G. van; Mischi, Massimo [Lab. of Biomedical Diagnostics, Dept. of Electrical Eng., Eindhoven University of Technology (Netherlands); Wijkstra, Hessel [Lab. of Biomedical Diagnostics, Dept. of Electrical Eng., Eindhoven University of Technology (Netherlands); Academic Medical Center, Urology Dept., University of Amsterdam (Netherlands)

    2015-10-28

    Recently, a new acoustic marker for ultrasound contrast agents (UCAs) has been introduced. A cumulative phase delay (CPD) between the second harmonic and fundamental pressure wave field components is in fact observable for ultrasound propagating through UCAs. This phenomenon is absent in the case of tissue nonlinearity and is dependent on insonating pressure and frequency, UCA concentration, and propagation path length through UCAs. In this paper, ultrasound images based on this marker are presented. The ULA-OP research platform, in combination with a LA332 linear array probe (Esaote, Firenze Italy), were used to image a gelatin phantom containing a PVC plate (used as a reflector) and a cylindrical cavity measuring 7 mm in diameter (placed in between the observation point and the PVC plate). The cavity contained a 240 µL/L SonoVueO{sup ®} UCA concentration. Two insonating frequencies (3 MHz and 2.5 MHz) were used to scan the gelatine phantom. A mechanical index MI = 0.07, measured in water at the cavity location with a HGL-0400 hydrophone (Onda, Sunnyvale, CA), was utilized. Processing the ultrasound signals backscattered from the plate, ultrasound images were generated in a tomographic fashion using the filtered back-projection method. As already observed in previous studies, significantly higher CPD values are measured when imaging at a frequency of 2.5 MHz, as compared to imaging at 3 MHz. In conclusion, these results confirm the applicability of the discussed CPD as a marker for contrast imaging. Comparison with standard contrast-enhanced ultrasound imaging modalities will be the focus of future work.

  1. CUMULATIVE IMPACT OF YOGA PRACTICE ON QUALITY OF LI FE

    Directory of Open Access Journals (Sweden)

    Usha Rani

    2013-05-01

    Full Text Available ABSTRACT: The present study was conducted with two main objec tives. First it aims to experiment whether the ancient system of yoga can bring about change in the quality of life of its practitioners. The second objective was to study the cumulative im pact of yoga practice on Quality of Life. The study was conducted on four independent groups of y oga practitioners that varied in their length of experience in yoga practice. The first group compri sed of 76 subjects (49 male and 27 female with a mean age of 39 years (SD=9.8. All the participan ts in this group are novice practitioners. They have participated in the study immediately after th eir admission into yoga class. The second group comprised of 23 subjects (14 male and 9 female wit h a mean age of 34.2 years (SD= 11.07. Their length of experience in yoga practice is 3 months. The third group comprised of 18 subjects (11male and 7 female with a mean age of 33.83 year s (SD=9.33. Their length of experience in yoga practice is six months. The fourth group comprised of 17 subjects (11 male and 6 female with a mean age of 32.8 years (SD=9.5. Their length exper ience is 12 months. All the four independent groups were administered a questionnaire on Quality of Life (WHOQOL-BREF. The results on QOL gave scores on to tal quality of life and separate scores on Domain 1 (dealing with physical health Domain 2 (d ealing with psychological aspects, Domain 3 (dealing with social relationships and Domain 4 (d ealing with environmental aspects.

  2. Measuring a fair and ambitious climate agreement using cumulative emissions

    Science.gov (United States)

    Peters, Glen P.; Andrew, Robbie M.; Solomon, Susan; Friedlingstein, Pierre

    2015-10-01

    Policy makers have called for a ‘fair and ambitious’ global climate agreement. Scientific constraints, such as the allowable carbon emissions to avoid exceeding a 2 °C global warming limit with 66% probability, can help define ambitious approaches to climate targets. However, fairly sharing the mitigation challenge to meet a global target involves human values rather than just scientific facts. We develop a framework based on cumulative emissions of carbon dioxide to compare the consistency of countries’ current emission pledges to the ambition of keeping global temperatures below 2 °C, and, further, compare two alternative methods of sharing the remaining emission allowance. We focus on the recent pledges and other official statements of the EU, USA, and China. The EU and US pledges are close to a 2 °C level of ambition only if the remaining emission allowance is distributed based on current emission shares, which is unlikely to be viewed as ‘fair and ambitious’ by others who presently emit less. China’s stated emissions target also differs from measures of global fairness, owing to emissions that continue to grow into the 2020s. We find that, combined, the EU, US, and Chinese pledges leave little room for other countries to emit CO2 if a 2 °C limit is the objective, essentially requiring all other countries to move towards per capita emissions 7 to 14 times lower than the EU, USA, or China by 2030. We argue that a fair and ambitious agreement for a 2 °C limit that would be globally inclusive and effective in the long term will require stronger mitigation than the goals currently proposed. Given such necessary and unprecedented mitigation and the current lack of availability of some key technologies, we suggest a new diplomatic effort directed at ensuring that the necessary technologies become available in the near future.

  3. Cumulative Effects of Barriers on the Movements of Forest Birds

    Directory of Open Access Journals (Sweden)

    Marc Bélisle

    2002-01-01

    Full Text Available Although there is a consensus of opinion that habitat fragmentation has deleterious effects on animal populations, primarily by inhibiting dispersal among remaining patches, there have been few explicit demonstrations of the ways by which degraded habitats actually constrain individual movement. Two impediments are primarily responsible for this paucity: it is difficult to separate the effects of habitat fragmentation (configuration from habitat loss (composition, and conventional measures of fragmented habitats are assumed to be, but probably are not, isotropic. We addressed these limitations by standardizing differences in forest cover in a clearly anisotropic configuration of habitat fragmentation by conducting a homing experiment with three species of forest birds in the Bow Valley of Banff National Park, Canada. Birds were translocated (1.2-3.5  km either parallel or perpendicular to four/five parallel barriers that are assumed to impede the cross-valley travel of forest-dependent animals. Taken together, individuals exhibited longer return times when they were translocated across these barriers, but differences among species suggest a more complex interpretation. A long-distance migrant (Yellow-rumped Warbler, Dendroica coronata behaved as predicted, but a short-distance migrant (Golden-crowned Kinglet, Regulus satrapa was indifferent to barrier configuration. A resident (Red-breasted Nuthatch, Sitta canadensis exhibited longer return times when it was translocated parallel to the barriers. Our results suggest that an anisotropic arrangement of small, open areas in fragmented landscapes can have a cumulative barrier effect on the movement of forest animals, but that both modelers and managers will have to acknowledge potentially counterintuitive differences among species to predict the effect that these may have on individual movement and, ultimately, dispersal.

  4. Emission of thermally stimulated luminescence in mixed monocrystals KCl-KBr: Pb{sup 2+}, KCl: Pb{sup 2+} and KBr: Pb{sup 2+} exposed at low doses; Emision de luminiscencia estimulada termicamente en monocristales mixtos KCl-KBr:Pb{sup 2+}, KCl:Pb{sup 2+} y KBr:Pb{sup 2+} expuestos a dosis bajas

    Energy Technology Data Exchange (ETDEWEB)

    Cruz Z, E.; Ramos B, S. [Instituto de Ciencias Nucleares UNAM, A.P. 70-543, 04510 Mexico D.F. (Mexico); Melendrez A, R.; Chernov, V.; Piters, T.M.; Barboza F, M. [Centro de Investigacion en Fisica, Universidad de Sonora, A.P. 5-88 Hermosillo, Sonora (Mexico); Hernandez A, J.; Murrieta S, H. [Instituto de Fisica UNAM, A.P. 20-364, 01000 Mexico D.F. (Mexico)

    2002-07-01

    It is reported the behavior of solid solutions of mixed crystals KCl{sub 1-x} KBr{sub x} doped with divalent lead which were exposed to gamma radiation. The mixtures of KCl-KBr were varied, with x equivalents at 2, 50, 65, and 85 % including the extremes KCl: Pb{sup 2+} and KBr: Pb{sup 2+}. It was maintained a concentration of divalent lead between 20 and 40 ppm in the crystalline lattice. The production of the generated defects by radiation have been correlated with the increase in the brilliance curves depending on the received dose by the mixed doped crystal. It has been used the thermal stimulation (Tl) for obtaining the crystal luminescence depending on the dose until 130 Gy with gammas of cobalt 60. The results shows that this mixed crystalline material of varied composition responds adequately to low doses which indicates that this would be a good detector of ionizing radiation. The results have been correlated with the optical properties of this mixed doped crystal, however it has been found that exists an important loss of luminescence depending on the halogen quantity presents in the mixed crystal. (Author)

  5. Pilot point temperature regulation for thermal lesion control during ultrasound thermal therapy.

    Science.gov (United States)

    Liu, H L; Chen, Y Y; Yen, J Y; Lin, W L

    2004-03-01

    The fundamental goal of ultrasound thermal therapy is to provide proper thermal lesion formations for effective tumour treatment. The quality of the therapy depends mostly on its positional precision. To date, most ultrasound thermal therapy treatments have focused on the formation of power or temperature patterns. The non-linear and time-delay effects of thermal dose formation prohibit direct control of the thermal dose distribution. In the paper, the control of thermal lesions by regulation of the temperature of a pilot point is proposed. This scheme utilises the high correlation between temperature elevation and thermal dose at the forward boundary of thermal lesions. To verify the feasibility, a 2D ultrasound phased array system was used to generate thermal lesions of various sizes, and the temperature elevation required to generate a thermal dose threshold was investigated. Results showed that the required temperature elevation was found to be a reasonably constant value of 52.5 degrees C under differing conditions when the focal area was small. When the focal area under consideration was large, the required temperature elevation became a monotonic function of blood perfusion rate, ranging from 49.2 to 52.5 degrees C. When the reference temperature of the pilot point was set at a conservative value (52.5 degrees C), the thermal lesions were controlled precisely under a wide range of blood perfusion and power pattern changes, tested by using a more realistic model that takes into account thermal-induced attenuation and blood perfusion changes. This changed the complex thermal dose control problem into a simple temperature regulation problem, which makes implementation of thermal lesion control easier, giving the scheme a high potential for application to current ultrasound thermal therapy systems.

  6. Use of Cumulative Examinations at U.S. Schools of Pharmacy.

    Science.gov (United States)

    Ryan, Gina J.; Nykamp, Diane

    2000-01-01

    Surveyed department of pharmacy chairs at 77 schools of pharmacy about current use of cumulative exams. Found that more than 80 percent do not administer cumulative exams and that the primary rationale for such exams is to encourage students to review material prior to advancement; they are rarely used to determine advancement. (EV)

  7. The Scarring Effects of Bankruptcy: Cumulative Disadvantage across Credit and Labor Markets

    Science.gov (United States)

    Maroto, Michelle

    2012-01-01

    As the recent economic crisis has demonstrated, inequality often spans credit and labor markets, supporting a system of cumulative disadvantage. Using data from the National Longitudinal Survey of Youth, this research draws on stigma, cumulative disadvantage and status characteristics theories to examine whether credit and labor markets intersect…

  8. Origin of path independence between cumulative CO2 emissions and global warming

    Science.gov (United States)

    Seshadri, Ashwin K.

    2017-02-01

    Observations and GCMs exhibit approximate proportionality between cumulative carbon dioxide (CO2 ) emissions and global warming. Here we identify sufficient conditions for the relationship between cumulative CO2 emissions and global warming to be independent of the path of CO2 emissions; referred to as "path independence". Our starting point is a closed form expression for global warming in a two-box energy balance model (EBM), which depends explicitly on cumulative emissions, airborne fraction and time. Path independence requires that this function can be approximated as depending on cumulative emissions alone. We show that path independence arises from weak constraints, occurring if the timescale for changes in cumulative emissions (equal to ratio between cumulative emissions and emissions rate) is small compared to the timescale for changes in airborne fraction (which depends on CO2 uptake), and also small relative to a derived climate model parameter called the damping-timescale, which is related to the rate at which deep-ocean warming affects global warming. Effects of uncertainties in the climate model and carbon cycle are examined. Large deep-ocean heat capacity in the Earth system is not necessary for path independence, which appears resilient to climate modeling uncertainties. However long time-constants in the Earth system carbon cycle are essential, ensuring that airborne fraction changes slowly with timescale much longer than the timescale for changes in cumulative emissions. Therefore path independence between cumulative emissions and warming cannot arise for short-lived greenhouse gases.

  9. Short- and Long-Term Effects of Cumulative Finals on Student Learning

    Science.gov (United States)

    Khanna, Maya M.; Brack, Amy S. Badura; Finken, Laura L.

    2013-01-01

    In two experiments, we examined the benefits of cumulative and noncumulative finals on students' short- and long-term course material retention. In Experiment 1, we examined results from course content exams administered immediately after course finals. Course sections including cumulative finals had higher content exam scores than sections…

  10. Cumulative effects of planned industrial development and climate change on marine ecosystems

    Directory of Open Access Journals (Sweden)

    Cathryn Clarke Murray

    2015-07-01

    Full Text Available With increasing human population, large scale climate changes, and the interaction of multiple stressors, understanding cumulative effects on marine ecosystems is increasingly important. Two major drivers of change in coastal and marine ecosystems are industrial developments with acute impacts on local ecosystems, and global climate change stressors with widespread impacts. We conducted a cumulative effects mapping analysis of the marine waters of British Columbia, Canada, under different scenarios: climate change and planned developments. At the coast-wide scale, climate change drove the largest change in cumulative effects with both widespread impacts and high vulnerability scores. Where the impacts of planned developments occur, planned industrial and pipeline activities had high cumulative effects, but the footprint of these effects was comparatively localized. Nearshore habitats were at greatest risk from planned industrial and pipeline activities; in particular, the impacts of planned pipelines on rocky intertidal habitats were predicted to cause the highest change in cumulative effects. This method of incorporating planned industrial development in cumulative effects mapping allows explicit comparison of different scenarios with the potential to be used in environmental impact assessments at various scales. Its use allows resource managers to consider cumulative effect hotspots when making decisions regarding industrial developments and avoid unacceptable cumulative effects. Management needs to consider both global and local stressors in managing marine ecosystems for the protection of biodiversity and the provisioning of ecosystem services.

  11. Aging and Cumulative Inequality: How Does Inequality Get Under the Skin?

    Science.gov (United States)

    Ferraro, Kenneth F.; Shippee, Tetyana Pylypiv

    2009-01-01

    Purpose: This article draws from cumulative disadvantage and life course theories to develop a new theory for the social scientific study of aging. Design and Methods: Five axioms of "cumulative inequality (CI) theory" are articulated to identify how life course trajectories are influenced by early and accumulated inequalities but can be modified…

  12. The Scarring Effects of Bankruptcy: Cumulative Disadvantage across Credit and Labor Markets

    Science.gov (United States)

    Maroto, Michelle

    2012-01-01

    As the recent economic crisis has demonstrated, inequality often spans credit and labor markets, supporting a system of cumulative disadvantage. Using data from the National Longitudinal Survey of Youth, this research draws on stigma, cumulative disadvantage and status characteristics theories to examine whether credit and labor markets intersect…

  13. Cumulative Advantage and Success-Breeds-Success: The Value of Time Pattern Analysis.

    Science.gov (United States)

    Huber, John C.

    1998-01-01

    For the case of the distribution of papers across authors, the Success-Breeds-Success or Cumulative Advantage model is a popular candidate for informetrics. The method of time pattern of publication for individual authors can be used to discriminate between Cumulative Advantage and non-uniform giftedness models. The non-uniform giftedness model is…

  14. 43 CFR 46.115 - Consideration of past actions in the analysis of cumulative effects.

    Science.gov (United States)

    2010-10-01

    ... Environmental Quality § 46.115 Consideration of past actions in the analysis of cumulative effects. When... Memorandum on Consideration of Past Actions in Cumulative Effects Analysis” dated June 24, 2005, or any... 43 Public Lands: Interior 1 2010-10-01 2010-10-01 false Consideration of past actions in...

  15. UNIDIMENSIONALITY AND CUMULATIVENESS OF THE LONELINESS SCALE USING MOKKEN-SCALE-ANALYSIS FOR POLYCHOTOMOUS ITEMS

    NARCIS (Netherlands)

    MOORER, P; SUURMEIJER, TPBM

    1993-01-01

    The unidimensionality and cumulativeness of the Loneliness Scale of De Jong-Gierveld was investigated using the Mokken Scale Analysis for polychotomous items. 10 of the 11 items of the original Loneliness Scale constituted a unidimensional, cumulative scale, with a homogeneity coefficient H of 0.37

  16. The effects of antipoverty programs on children's cumulative level of poverty-related risk.

    Science.gov (United States)

    Gassman-Pines, Anna; Yoshikawa, Hirokazu

    2006-11-01

    The authors examined the effects of antipoverty programs on children's cumulative poverty-related risk and the relationship between cumulative poverty-related risk and child outcomes among low-income families. Samples included 419 children ages 3-10 years in the New Hope program and 759 children ages 2-9 years in the Minnesota Family Investment Program (MFIP), which tested 2 program approaches. Nine poverty-related risks made up the measure of cumulative risk. Both MFIP program approaches reduced cumulative poverty-related risk. New Hope reduced cumulative poverty-related risk among long-term welfare recipients. In both New Hope and MFIP, significant linear relationships between cumulative poverty-related risk and parent-reported behavior problems and school achievement were found. Cumulative poverty-related risk partially mediated the impacts of the MFIP programs on children's behavior problems. Among long-term welfare recipients, cumulative poverty-related risk partially mediated New Hope's impact on parent-reported school achievement.

  17. 14 CFR Section 18 - Objective Classification-Cumulative Effect of Changes in Accounting Principles

    Science.gov (United States)

    2010-01-01

    ... of Changes in Accounting Principles Section 18 Section 18 Aeronautics and Space OFFICE OF THE... Objective Classification—Cumulative Effect of Changes in Accounting Principles 98Cumulative Effect of Changes in Accounting Principles. Record here the difference between the amount of retained earnings...

  18. Asymptotic growth of cumulative and regenerative beam break-up instabilities in accelerators

    Science.gov (United States)

    Lau, Y. Y.

    1988-06-01

    It is found that the asymptotic growth of the cumulative beam break up instability is independent of the focusing magnetic field, according to the model of Panofsky and Bander. The analysis is extended to include the transition from the cumulative to the regenerative type, both in the presence and absence of a focusing magnetic field.

  19. A Cumulative Damage Reliability Model on the Basis of Contact Fatigue of the Rolling Bearing

    Institute of Scientific and Technical Information of China (English)

    HUANG Li

    2006-01-01

    A cumulative damage reliability model of contact fatigue of the rolling bearing is more identical with the actual conditions. It is put forward on the basis of contact fatigue life probability distribution of the rolling bearing that obey Weibull distribution and rest on the Miner cumulative damage theory. Finally a case is given to predict the reliability of bearing roller by using these models.

  20. Estimating multi-factor cumulative watershed effects on fish populations with an individual-based model

    Science.gov (United States)

    Bret C. Harvey; Steven F. Railsback

    2007-01-01

    While the concept of cumulative effects is prominent in legislation governing environmental management, the ability to estimate cumulative effects remains limited. One reason for this limitation is that important natural resources such as fish populations may exhibit complex responses to changes in environmental conditions, particularly to alteration of multiple...

  1. Countermeasures to Neurobehavioral Deficits from Cumulative Partial Sleep Deprivation During Space Flight

    Science.gov (United States)

    Dinges, David F.

    1999-01-01

    sleep attacks. The prevention of cumulative performance deficits and neuroendocrine disruption from sleep restriction during extended duration space flight involves finding the most effective ways to obtain sleep in order to maintain the high-level cognitive and physical performance functions required for manned space flight. There is currently a critical deficiency in knowledge of the effects of how variations in sleep duration and timing relate to the most efficient return of performance per unit time invested in sleep during long-duration missions, and how the nature of sleep physiology (i.e., sleep stages, sleep electroencephalographic [EEG] power spectral analyses) change as a function of sleep restriction and performance degradation. The primary aim of this project is to meet these critical deficiencies through utilization of a response surface experimental paradigm, testing in a dose-response manner, varying combinations of sleep duration and timing, for the purpose of establishing how to most effectively limit the cumulative adverse effects on human performance and physiology of chronic sleep restriction in space operations.

  2. External dose reconstruction in tooth enamel of Techa riverside residents

    Energy Technology Data Exchange (ETDEWEB)

    Shishkina, E.A.; Volchkova, A.Yu.; Krivoschapov, V.A.; Degteva, M.O. [Urals Research Center for Radiation Medicine, Chelyabinsk (Russian Federation); Timofeev, Y.S.; Zalyapin, V.I. [Southern Urals State University, Chelyabinsk (Russian Federation); Fattibene, P.; Della Monaca, S.; De Coste, V. [Istituto Superiore di Sanita e Istituto Nazionale di Fisica Nucleare, Rome (Italy); Wieser, A. [Helmholtz Zentrum Muenchen, German Research Centre for Environmental Health, Neuherberg (Germany); Ivanov, D.V. [M.N. Mikheev Institute of Metal Physics, Ural Division of the Russian Academy of Sciences, Ekaterinburg (Russian Federation); Ural Federal University, Yekaterinburg (Russian Federation); Anspaugh, L.R. [University of Utah, Salt Lake City, UT (United States)

    2016-11-15

    This study summarizes the 20-year efforts for dose reconstruction in tooth enamel of the Techa riverside residents exposed to ionizing radiation as a result of radionuclide releases into the river in 1949-1956. It represents the first combined analysis of all the data available on EPR dosimetry with teeth of permanent residents of the Techa riverside territory. Results of electron paramagnetic resonance (EPR) measurements of 302 teeth donated by 173 individuals living permanently in Techa riverside settlements over the period of 1950-1952 were analyzed. These people were residents of villages located at the free-flowing river stream or at the banks of stagnant reservoirs such as ponds or blind river forks. Cumulative absorbed doses measured using EPR are from several sources of exposure, viz., background radiation, internal exposure due to bone-seeking radionuclides ({sup 89}Sr, {sup 90}Sr/{sup 90}Y), internal exposure due to {sup 137}Cs/{sup 137m}Ba incorporated in soft tissues, and anthropogenic external exposure. The purpose of the present study was to evaluate the contribution of different sources of enamel exposure and to deduce external doses to be used for validation of the Techa River Dosimetry System (TRDS). Since various EPR methods were used, harmonization of these methods was critical. Overall, the mean cumulative background dose was found to be 63 ± 47 mGy; cumulative internal doses due to {sup 89}Sr and {sup 90}Sr/{sup 90}Y were within the range of 10-110 mGy; cumulative internal doses due to {sup 137}Cs/{sup 137m}Ba depend on the distance from the site of releases and varied from 1 mGy up to 90 mGy; mean external doses were maximum for settlements located at the banks of stagnant reservoirs (∝500 mGy); in contrast, external doses for settlements located along the free-flowing river stream did not exceed 160 mGy and decreased downstream with increasing distance from the site of release. External enamel doses calculated using the TRDS code and

  3. Cumulative second-harmonic generation of Lamb waves propagating in a two-layered solid plate

    Institute of Scientific and Technical Information of China (English)

    Xiang Yan-Xun; Deng Ming-Xi

    2008-01-01

    The physical process of cumulative second-harmonic generation of Lamb waves propagating in a two-layered solid plate is presented by using the second-order perturbation and the technique of nonlinear reflection of acoustic waves at an interface.In general,the cumulative second-harmonic generation of a dispersive guided wave propagation does not occur.However,the present paper shows that the second-harmonic of Lamb wave propagation arising from the nonlinear interaction of the partial bulk acoustic waves and the restriction of the three boundaries of the solid plates does have a cumulative growth effect if some conditions are satisfied.Through boundary condition and initial condition of excitation,the analytical expression of cumulative second-harmonic of Lamb waves propagation is determined.Numerical results show the cumulative effect of Lamb waves on second-harmonic field patterns.

  4. Patient cumulative radiation exposure in interventional cardiology; Exposition cumulee aux rayonnements ionisants des patients en cardiologie interventionnelle: caracteristiques cliniques et dosimetriques

    Energy Technology Data Exchange (ETDEWEB)

    Bernier, M.O.; Jacob, S.; Laurier, D. [Institut de radioprotection et de surete nucleaire (IRSN), DRPH, SRBE, LEPID, Fontenay-aux-Roses (France); Maccia, C. [Centre d' assurance de qualite des applications technologiques dans le domaine de la sante - CAATS, Bourg-la-Reine (France); Bar, O.; Blanchard, D. [Clinique Saint-Gatien, Tours (France); Catelinois, O. [Institut de veille sanitaire, St Maurice (France)

    2012-01-15

    Interventional cardiology procedures can involve potentially high doses of radiation to the patients. Stochastic effects of ionising radiation - radiation-induced cancers in the long term - may occur. We analysed clinical characteristics and dosimetric data in a population of patients undergoing interventional cardiology. In all, 1 591 patients who had undergone coronarography and/or angioplasty in the course of a year at the Saint-Gatien Clinic in Tours (France) were included. Information on patients' individual clinical characteristics and Dose-Area Product values were collected. Organ doses to the lung, oesophagus, bone marrow and breast were mathematically evaluated. The median age of patients was 70 years. Their median cumulative dose-area product value was 48.4 Gy.cm{sup 2} for the whole year and the median effective dose was 9.7 mSv. The median organ doses were 41 mGy for the lung, 31 mGy for the oesophagus, 10 mGy for the bone marrow and 4 mGy for the breast. Levels of doses close to the heart appear to be rather high in the case of repeated interventional cardiology procedures. Clinical characteristics should be taken into account when planning epidemiological studies on potential radiation-induced cancers. (authors)

  5. Benchmark Dose Modeling

    Science.gov (United States)

    Finite doses are employed in experimental toxicology studies. Under the traditional methodology, the point of departure (POD) value for low dose extrapolation is identified as one of these doses. Dose spacing necessarily precludes a more accurate description of the POD value. ...

  6. Thermal annealing of high dose radiation induced damage at room temperature in alkaline. Stored energy, thermoluminescence and coloration; Aniquilacion termica de dano inducido por irradiacion a altas dosis en haluros alcalinos a 300 k. energia almacenda. Termoluminiscencia y coloracion

    Energy Technology Data Exchange (ETDEWEB)

    Delgado, L.

    1980-07-01

    The possible relation between stored energy, thermoluminescence and colour centre annealing in gamma and electron irradiated alkali halides is studied. Thermoluminescence occurs at temperature higher than the temperature at which the main stored energy peak appears. No stored energy release is detected in additively coloured KC1 samples. Plastic deformation and doping with Ca and Sr induce a stored energy spectrum different from the spectrum observed in pure and as cleaved samples, but the amount of stored energy does not change for a given irradiation dose.Capacity of alkali halides to store energy by irradiation increases as the cation size decreases. (Author) 51 refs.

  7. Predicting Cumulative Watershed Effects using Spatially Explicit Models

    Science.gov (United States)

    MacDonald, L. H.; Litschert, S.

    2004-12-01

    Cumulative watershed effects /(CWEs/) result from the combined effects of land disturbances distributed over both space and time. They are of concern because changes in flow and sediment yields can adversely affect aquatic habitat, channel morphology, water yields, and water quality. The assessment procedures currently used by agencies such as the U.S. Forest Service generally rely on a lumped approach to quantify disturbance, despite the widespread recognition that site conditions and location do matter! The overall goal of our work is to develop spatially-explicit models to quantify changes in flow and sediment yields. Key objectives include: use of readily available GIS data; ease of use for resource managers with minimal GIS experience; modularity so that models can be added or updated; and allowing users to select the models and values for key parameters. The DeltaQ model calculates changes in peak, median, and low flows due to forest management activities and fires. Inputs include GIS data with disturbance polygons, an initial change in flow rate, and the time to recovery. Data from paired watershed studies are provided to help guide the user. The initial version of FORest Erosion Simulation Tools /(FOREST/) calculates sediment production from forest harvest, fires, and unpaved roads. Additional modules are being developed to deliver this sediment to the stream channel and route it to downstream locations. In accordance with our objectives, the user can predict sediment production rates using different empirical equations, assign an initial sediment production rate and a specified linear recovery period, or develop a look-up table based on local knowledge, published values, or data from other models such as WEPP. The required GIS layers vary according to the model/(s/) selected, but generally include past disturbances /(e.g., fires and timber harvest/), roads, and elevation. Outputs include GIS layers and text files that can be subjected to additional

  8. Using the {sup 60}Co source to assess the dose received by risky organs during a cancer brain treatment; L'utilisation de la source {sup 60}Co pour evaluer la dose recue par les organes a risques au cours d'un traitement cerebral de cancer

    Energy Technology Data Exchange (ETDEWEB)

    Faik Ouahab, Z.; Jehouani, A.; Ghassoun, J.; Senhou, N. [EPRA, Departement of Physics, Cadi Ayyad University, Faculty of Science, Semlalia, BP. 2390, Marrakech (Morocco); Mouhssine, D. [Centre de traitement Al Kindy, Bd ibn Sina 2 et 3 Rue Al Kindy 20000, Casablanca (Morocco); Groetz, J.E. [Universite de Franche-Comte, Laboratoire de Chimie Physique et Rayonnements Alain Chambaudet, UMR CEA E4, 16, route de Gray, 25030 Besancon Cedex (France)

    2010-07-01

    Summary of an investigation of exposures associated with brain cancer treatment for a child in order to determine the level of doses received by the different organs at risk during the treatment. Measurements have been performed at the vicinity of a cobalto therapy apparatus. Then, cumulative doses in each organ have been compared to admitted doses with respect to the organ

  9. Fluid Overload and Cumulative Thoracostomy Output Are Associated With Surgical Site Infection After Pediatric Cardiothoracic Surgery.

    Science.gov (United States)

    Sochet, Anthony A; Nyhan, Aoibhinn; Spaeder, Michael C; Cartron, Alexander M; Song, Xiaoyan; Klugman, Darren; Brown, Anna T

    2017-08-01

    To determine the impact of cumulative, postoperative thoracostomy output, amount of bolus IV fluids and peak fluid overload on the incidence and odds of developing a deep surgical site infection following pediatric cardiothoracic surgery. A single-center, nested, retrospective, matched case-control study. A 26-bed cardiac ICU in a 303-bed tertiary care pediatric hospital. Cases with deep surgical site infection following cardiothoracic surgery were identified retrospectively from January 2010 through December 2013 and individually matched to controls at a ratio of 1:2 by age, gender, Risk Adjustment for Congenital Heart Surgery score, Society of Thoracic Surgeons-European Association for Cardiothoracic Surgery category, primary cardiac diagnosis, and procedure. None. Twelve cases with deep surgical site infection were identified and matched to 24 controls without detectable differences in perioperative clinical characteristics. Deep surgical site infection cases had larger thoracostomy output and bolus IV fluid volumes at 6, 24, and 48 hours postoperatively compared with controls. For every 1 mL/kg of thoracostomy output, the odds of developing a deep surgical site infection increase by 13%. By receiver operative characteristic curve analysis, a cutoff of 49 mL/kg of thoracostomy output at 48 hours best discriminates the development of deep surgical site infection (sensitivity 83%, specificity 83%). Peak fluid overload was greater in cases than matched controls (12.5% vs 6%; p thoracostomy output were associated with deep surgical site infection after pediatric cardiothoracic surgery. We suspect the observed increased thoracostomy output, fluid overload, and IV fluid boluses may have altered antimicrobial prophylaxis. Although analysis of additional pharmacokinetic data is warranted, providers may consider modification of antimicrobial prophylaxis dosing or alterations in fluid management and diuresis in response to assessment of peak fluid overload and fluid

  10. Assessing environmental impacts on stream water quality: the use of cumulative flux and cumulative flux difference approaches to deforestation of the Hafren Forest, mid-Wales

    Directory of Open Access Journals (Sweden)

    C. Neal

    2002-01-01

    Full Text Available A method for examining the impacts of disturbance on stream water quality based on paired catchment “controlâ€? and “responseâ€? water quality time series is described in relation to diagrams of cumulative flux and cumulative flux difference. The paper describes the equations used and illustrates the patterns expected for idealised flux changes followed by an application to stream water quality data for a spruce forested catchment, the Hore, subjected to clear fell. The water quality determinands examined are sodium, chloride, nitrate, calcium and acid neutralisation capacity. The anticipated effects of felling are shown in relation to reduction in mist capture and nitrate release with felling as well as to the influence of weathering and cation exchange mechanisms, but in a much clearer way than observed previously using other approaches. Keywords: Plynlimon, stream, Hore, acid neutralisation capacity, calcium, chloride, nitrate, sodium, cumulative flux, flux

  11. Elaboration of a concept for the cumulative environmental exposure assessment of biocides

    Energy Technology Data Exchange (ETDEWEB)

    Gross, Rita; Bunke, Dirk; Moch, Katja [Oeko-Institut e.V. - Institut fuer Angewandte Oekologie e.V., Freiburg im Breisgau (Germany); Gartiser, Stefan [Hydrotox GmbH, Freiburg im Breisgau (Germany)

    2011-12-15

    Article 10(1) of the EU Biocidal Products Directive 98/8/EC (BPD) requires that for the inclusion of an active substance in Annex I, Annex IA or IB, cumulation effects from the use of biocidal products containing the same active substance shall be taken into account, where relevant. The study proves the feasibility of a technical realisation of Article 10(1) of the BPD and elaborates a first concept for the cumulative environmental exposure assessment of biocides. Existing requirements concerning cumulative assessments in other regulatory frameworks have been evaluated and their applicability for biocides has been examined. Technical terms and definitions used in this context were documented with the aim to harmonise terminology with other frameworks and to set up a precise definition within the BPD. Furthermore, application conditions of biocidal products have been analysed to find out for which cumulative exposure assessments may be relevant. Different parameters were identified which might serve as indicators for the relevance of cumulative exposure assessments. These indicators were then integrated in a flow chart by means of which the relevance of cumulative exposure assessments can be checked. Finally, proposals for the technical performance of cumulative exposure assessments within the Review Programme have been elaborated with the aim to bring the results of the project into the upcoming development and harmonization processes on EU level. (orig.)

  12. The cumulative semantic cost does not reflect lexical selection by competition☆

    Science.gov (United States)

    Navarrete, Eduardo; Mahon, Bradford Z.; Caramazza, Alfonso

    2010-01-01

    The cumulative semantic cost describes a phenomenon in which picture naming latencies increase monotonically with each additional within-category item that is named in a sequence of pictures. Here we test whether the cumulative semantic cost requires the assumption of lexical selection by competition. In Experiment 1 participants named a sequence of pictures, while in Experiment 2 participants named words instead of pictures, preceded by a gender marked determiner. We replicate the basic cumulative semantic cost with pictures (Exp. 1) and show that there is no cumulative semantic cost for word targets (Exp. 2). This pattern was replicated in Experiment 3 in which pictures and words were named along with their gender marked definite determiner, and were intermingled within the same experimental design. In addition, Experiment 3 showed that while picture naming induces a cumulative semantic cost for subsequently named words, word naming does not induce a cumulative semantic cost for subsequently named pictures. These findings suggest that the cumulative semantic cost arises prior to lexical selection and that the effect arises due to incremental changes to the connection weights between semantic and lexical representations. PMID:20347062

  13. Advanced Treatment Planning in Cancer Thermal Therapies

    Institute of Scientific and Technical Information of China (English)

    Theodoros SAMARAS; Esra NEUFELD; Niels KUSTER

    2016-01-01

    CEM43 thermal dose is a very common concept in thermal oncology. Thermal dose is the maximum amount of energy that can be transmitted during hyperthermia therapy conducted on temperature-sensitive tissue. Thermal dose is also the maximum value of local energy accumulation in human bodies, which can lead to tissue injury and pain. Thermal dose can also decrease the ifnishing temperature and reduce the energy to the tolerable range. There are two functions of the individualized hyperthermia treatment plan: it determines the setting and location that can realize the best tumor hyperthermia therapy; at the same time, it can decrease the effect of hyperthermia therapy on healthy tissues. There are four steps in the treatment plan of hyperthermia therapy for tumors: the ifrst step is to establish a three dimensional human body model and its corresponding an atomical structure that can be used in numerical algorithmvia medical imaging resources; the second step is to determine the volume of the electromagnetic energy accumulation. Based on the peculiarity of frequency and materials, even full-wave electromagnetic wave or quasi-static technique can be used to determine the tissue distribution. Evaluation of the therapy can be conducted based on thermal dose and the corresponding tissue damage model; the third step is to use Arrhenius model to provide direct evaluation of tissues in the thermal ablation zone, solidiifcation zone, as well as the necrotic area; the last step is the optimization of the treatment plan.

  14. Oil spill characterization in the hybrid polarity SAR domain using log-cumulants

    Science.gov (United States)

    Espeseth, Martine M.; Skrunes, Stine; Brekke, Camilla; Salberg, Arnt-Børre; Jones, Cathleen E.; Holt, Benjamin

    2016-10-01

    Log-cumulants have proven to be an interesting tool for evaluating the statistical properties of potential oil spills in polarimetric Synthetic Aperture Radar (SAR) data within the common horizontal (H) and vertical (V) polarization basis. The use of first, second, and third order sample log-cumulants has shown potential for evaluating the texture and the statistical distributions, as well as discriminating oil from look-alikes. Log-cumulants are cumulants derived in the log-domain and can be applied to both single-polarization and multipolarization SAR data. This study is the first to investigate the differences between hybrid-polarity (HP) and full-polarimetric (FP) modes based on the sample log-cumulants of various oil slicks and open water from nine Uninhabited Aerial Vehicle Synthetic Aperture Radar (UAVSAR) scenes acquired off the coast of Norway in 2015. The sample log-cumulants calculated from the HP intensities show similar statistical behavior to the FP ones, resulting in a similar interpretation of the sample log-cumulants from HP and FP. Approximately eight hours after release the sample log-cumulants representing emulsion slicks have become more similar to the open water compared to plant oil. We find that the sample log-cumulants of the various oil slicks and open water varies between the scenes and also between the slicks and open water. This might be due to changes in ocean and wind condition, the initial slick properties, and/or the difference in the weathering process of the oil slicks.

  15. Cumulative Measurement Errors for Dynamic Testing of Space Flight Hardware

    Science.gov (United States)

    Winnitoy, Susan

    2012-01-01

    measurements during hardware motion and contact. While performing dynamic testing of an active docking system, researchers found that the data from the motion platform, test hardware and two external measurement systems exhibited frame offsets and rotational errors. While the errors were relatively small when considering the motion scale overall, they substantially exceeded the individual accuracies for each component. After evaluating both the static and dynamic measurements, researchers found that the static measurements introduced significantly more error into the system than the dynamic measurements even though, in theory, the static measurement errors should be smaller than the dynamic. In several cases, the magnitude of the errors varied widely for the static measurements. Upon further investigation, researchers found the larger errors to be a consequence of hardware alignment issues, frame location and measurement technique whereas the smaller errors were dependent on the number of measurement points. This paper details and quantifies the individual and cumulative errors of the docking system and describes methods for reducing the overall measurement error. The overall quality of the dynamic docking tests for flight hardware verification was improved by implementing these error reductions.

  16. Computed tomography dose optimisation in cystic fibrosis:A review

    Institute of Scientific and Technical Information of China (English)

    Helena Ferris; Maria Twomey; Fiachra Moloney; Siobhan B O’Neill; Kevin Murphy; Owen J O’Connor; Michael Maher

    2016-01-01

    Cystic fibrosis(CF)is the most common autosomal recessive disease of the Caucasian population worldwide,with respiratory disease remaining the most relevant source of morbidity and mortality.Computed tomography(CT)is frequently used for monitoring disease complications and progression.Over the last fifteen years there has been a six-fold increase in the use of CT,which has lead to a growing concern in relation to cumulative radiation exposure.The challenge to the medical profession is to identify dose reduction strategies that meet acceptable image quality,but fulfil the requirements of a diagnostic quality CT.Dose-optimisation,particularly in CT,is essential as it reduces the chances of patients receiving cumulative radiation doses in excess of 100 m Sv,a dose deemed significant by the United Nations Scientific Committee on the Effects of Atomic Radiation.This review article explores the current trends in imaging in CF with particular emphasis on new developments in dose optimisation.

  17. Structure functions and particle production in the cumulative region two different exponentials

    CERN Document Server

    Braun, M

    1996-01-01

    In the framework of the recently proposed QCD based parton model for the cumulative phenomena in the interactions with nuclei two mechanisms for particle production, direct and spectator ones, are analysed. It is shown that due to final state interactions the leading terms of the direct mechanism contribution are cancelled and the spectator mechanism is the dominant one. It leads to a smaller slope of the cumulative particle production rates compared to the slope of the nuclear structure function in the cumulative region x>1, in agreement with the recent experimental data.

  18. SU-F-P-19: Fetal Dose Estimate for a High-Dose Fluoroscopy Guided Intervention Using Modern Data Tools

    Energy Technology Data Exchange (ETDEWEB)

    Moirano, J [University of Washington, Seattle, WA (United States)

    2016-06-15

    Purpose: An accurate dose estimate is necessary for effective patient management after a fetal exposure. In the case of a high-dose exposure, it is critical to use all resources available in order to make the most accurate assessment of the fetal dose. This work will demonstrate a methodology for accurate fetal dose estimation using tools that have recently become available in many clinics, and show examples of best practices for collecting data and performing the fetal dose calculation. Methods: A fetal dose estimate calculation was performed using modern data collection tools to determine parameters for the calculation. The reference point air kerma as displayed by the fluoroscopic system was checked for accuracy. A cumulative dose incidence map and DICOM header mining were used to determine the displayed reference point air kerma. Corrections for attenuation caused by the patient table and pad were measured and applied in order to determine the peak skin dose. The position and depth of the fetus was determined by ultrasound imaging and consultation with a radiologist. The data collected was used to determine a normalized uterus dose from Monte Carlo simulation data. Fetal dose values from this process were compared to other accepted calculation methods. Results: An accurate high-dose fetal dose estimate was made. Comparison to accepted legacy methods were were within 35% of estimated values. Conclusion: Modern data collection and reporting methods ease the process for estimation of fetal dose from interventional fluoroscopy exposures. Many aspects of the calculation can now be quantified rather than estimated, which should allow for a more accurate estimation of fetal dose.

  19. Low dose ionizing radiation induced acoustic neuroma: A putative link?

    Directory of Open Access Journals (Sweden)

    Sachin A Borkar

    2012-01-01

    Full Text Available Although exposure to high dose ionizing radiation (following therapeutic radiotherapy has been incriminated in the pathogenesis of many brain tumors, exposure to chronic low dose ionizing radiation has not yet been shown to be associated with tumorigenesis. The authors report a case of a 50-year-old atomic reactor scientist who received a cumulative dose of 78.9 mSv over a 10-year period and was detected to have an acoustic neuroma another 15 years later. Although there is no proof that exposure to ionizing radiation was the cause for the development of the acoustic neuroma, this case highlights the need for extended follow-up periods following exposure to low dose ionizing radiation.

  20. Measurement of higher cumulants of net-charge multiplicity distributions in Au +Au collisions at √{sN N}=7.7 -200 GeV

    Science.gov (United States)

    Adare, A.; Afanasiev, S.; Aidala, C.; Ajitanand, N. N.; Akiba, Y.; Akimoto, R.; Al-Bataineh, H.; Alexander, J.; Al-Ta'Ani, H.; Angerami, A.; Aoki, K.; Apadula, N.; Aramaki, Y.; Asano, H.; Aschenauer, E. C.; Atomssa, E. T.; Averbeck, R.; Awes, T. C.; Azmoun, B.; Babintsev, V.; Bai, M.; Baksay, G.; Baksay, L.; Bannier, B.; Barish, K. N.; Bassalleck, B.; Basye, A. T.; Bathe, S.; Baublis, V.; Baumann, C.; Baumgart, S.; Bazilevsky, A.; Belikov, S.; Belmont, R.; Bennett, R.; Berdnikov, A.; Berdnikov, Y.; Bickley, A. A.; Black, D.; Blau, D. S.; Bok, J. S.; Boyle, K.; Brooks, M. L.; Bryslawskyj, J.; Buesching, H.; Bumazhnov, V.; Bunce, G.; Butsyk, S.; Camacho, C. M.; Campbell, S.; Castera, P.; Chen, C.-H.; Chi, C. Y.; Chiu, M.; Choi, I. J.; Choi, J. B.; Choi, S.; Choudhury, R. K.; Christiansen, P.; Chujo, T.; Chung, P.; Chvala, O.; Cianciolo, V.; Citron, Z.; Cole, B. A.; Connors, M.; Constantin, P.; Cronin, N.; Crossette, N.; Csanád, M.; Csörgő, T.; Dahms, T.; Dairaku, S.; Danchev, I.; Das, K.; Datta, A.; Daugherity, M. S.; David, G.; Dehmelt, K.; Denisov, A.; Deshpande, A.; Desmond, E. J.; Dharmawardane, K. V.; Dietzsch, O.; Ding, L.; Dion, A.; Do, J. H.; Donadelli, M.; D'Orazio, L.; Drapier, O.; Drees, A.; Drees, K. A.; Durham, J. M.; Durum, A.; Dutta, D.; Edwards, S.; Efremenko, Y. V.; Ellinghaus, F.; Engelmore, T.; Enokizono, A.; En'yo, H.; Esumi, S.; Eyser, K. O.; Fadem, B.; Fields, D. E.; Finger, M.; Finger, M.; Fleuret, F.; Fokin, S. L.; Fraenkel, Z.; Frantz, J. E.; Franz, A.; Frawley, A. D.; Fujiwara, K.; Fukao, Y.; Fusayasu, T.; Gainey, K.; Gal, C.; Garg, P.; Garishvili, A.; Garishvili, I.; Giordano, F.; Glenn, A.; Gong, H.; Gong, X.; Gonin, M.; Goto, Y.; Granier de Cassagnac, R.; Grau, N.; Greene, S. V.; Grosse Perdekamp, M.; Gu, Y.; Gunji, T.; Guo, L.; Gustafsson, H.-Å.; Hachiya, T.; Haggerty, J. S.; Hahn, K. I.; Hamagaki, H.; Hamblen, J.; Han, R.; Hanks, J.; Hartouni, E. P.; Hashimoto, K.; Haslum, E.; Hayano, R.; Hayashi, S.; He, X.; Heffner, M.; Hemmick, T. K.; Hester, T.; Hill, J. C.; Hohlmann, M.; Hollis, R. S.; Holzmann, W.; Homma, K.; Hong, B.; Horaguchi, T.; Hori, Y.; Hornback, D.; Huang, S.; Ichihara, T.; Ichimiya, R.; Ide, J.; Iinuma, H.; Ikeda, Y.; Imai, K.; Imazu, Y.; Imrek, J.; Inaba, M.; Iordanova, A.; Isenhower, D.; Ishihara, M.; Isinhue, A.; Isobe, T.; Issah, M.; Isupov, A.; Ivanishchev, D.; Jacak, B. V.; Javani, M.; Jia, J.; Jiang, X.; Jin, J.; Johnson, B. M.; Joo, K. S.; Jouan, D.; Jumper, D. S.; Kajihara, F.; Kametani, S.; Kamihara, N.; Kamin, J.; Kaneti, S.; Kang, B. H.; Kang, J. H.; Kang, J. S.; Kapustinsky, J.; Karatsu, K.; Kasai, M.; Kawall, D.; Kawashima, M.; Kazantsev, A. V.; Kempel, T.; Key, J. A.; Khandai, P. K.; Khanzadeev, A.; Kijima, K. M.; Kim, B. I.; Kim, C.; Kim, D. H.; Kim, D. J.; Kim, E.; Kim, E.-J.; Kim, H. J.; Kim, K.-B.; Kim, S. H.; Kim, Y.-J.; Kim, Y. K.; Kinney, E.; Kiriluk, K.; Kiss, Á.; Kistenev, E.; Klatsky, J.; Kleinjan, D.; Kline, P.; Kochenda, L.; Komatsu, Y.; Komkov, B.; Konno, M.; Koster, J.; Kotchetkov, D.; Kotov, D.; Kozlov, A.; Král, A.; Kravitz, A.; Krizek, F.; Kunde, G. J.; Kurita, K.; Kurosawa, M.; Kwon, Y.; Kyle, G. S.; Lacey, R.; Lai, Y. S.; Lajoie, J. G.; Lebedev, A.; Lee, B.; Lee, D. M.; Lee, J.; Lee, K.; Lee, K. B.; Lee, K. S.; Lee, S. H.; Lee, S. R.; Leitch, M. J.; Leite, M. A. L.; Leitgab, M.; Leitner, E.; Lenzi, B.; Lewis, B.; Li, X.; Liebing, P.; Lim, S. H.; Linden Levy, L. A.; Liška, T.; Litvinenko, A.; Liu, H.; Liu, M. X.; Love, B.; Luechtenborg, R.; Lynch, D.; Maguire, C. F.; Makdisi, Y. I.; Makek, M.; Malakhov, A.; Malik, M. D.; Manion, A.; Manko, V. I.; Mannel, E.; Mao, Y.; Maruyama, T.; Masui, H.; Masumoto, S.; Matathias, F.; McCumber, M.; McGaughey, P. L.; McGlinchey, D.; McKinney, C.; Means, N.; Meles, A.; Mendoza, M.; Meredith, B.; Miake, Y.; Mibe, T.; Midori, J.; Mignerey, A. C.; Mikeš, P.; Miki, K.; Milov, A.; Mishra, D. K.; Mishra, M.; Mitchell, J. T.; Miyachi, Y.; Miyasaka, S.; Mohanty, A. K.; Mohapatra, S.; Moon, H. J.; Morino, Y.; Morreale, A.; Morrison, D. P.; Moskowitz, M.; Motschwiller, S.; Moukhanova, T. V.; Murakami, T.; Murata, J.; Mwai, A.; Nagae, T.; Nagamiya, S.; Nagle, J. L.; Naglis, M.; Nagy, M. I.; Nakagawa, I.; Nakamiya, Y.; Nakamura, K. R.; Nakamura, T.; Nakano, K.; Nattrass, C.; Nederlof, A.; Netrakanti, P. K.; Newby, J.; Nguyen, M.; Nihashi, M.; Niida, T.; Nouicer, R.; Novitzky, N.; Nukariya, A.; Nyanin, A. S.; Obayashi, H.; O'Brien, E.; Oda, S. X.; Ogilvie, C. A.; Oka, M.; Okada, K.; Onuki, Y.; Oskarsson, A.; Ouchida, M.; Ozawa, K.; Pak, R.; Pantuev, V.; Papavassiliou, V.; Park, B. H.; Park, I. H.; Park, J.; Park, S.; Park, S. K.; Park, W. J.; Pate, S. F.; Patel, L.; Pei, H.; Peng, J.-C.; Pereira, H.; Perepelitsa, D. V.; Peresedov, V.; Peressounko, D. Yu.; Petti, R.; Pinkenburg, C.; Pisani, R. P.; Proissl, M.; Purschke, M. L.; Purwar, A. K.; Qu, H.; Rak, J.; Rakotozafindrabe, A.; Ravinovich, I.; Read, K. F.; Reygers, K.; Reynolds, D.; Riabov, V.; Riabov, Y.; Richardson, E.; Riveli, N.; Roach, D.; Roche, G.; Rolnick, S. D.; Rosati, M.; Rosen, C. A.; Rosendahl, S. S. E.; Rosnet, P.; Rukoyatkin, P.; Ružička, P.; Ryu, M. S.; Sahlmueller, B.; Saito, N.; Sakaguchi, T.; Sakashita, K.; Sako, H.; Samsonov, V.; Sano, M.; Sano, S.; Sarsour, M.; Sato, S.; Sato, T.; Sawada, S.; Sedgwick, K.; Seele, J.; Seidl, R.; Semenov, A. Yu.; Sen, A.; Seto, R.; Sett, P.; Sharma, D.; Shein, I.; Shibata, T.-A.; Shigaki, K.; Shimomura, M.; Shoji, K.; Shukla, P.; Sickles, A.; Silva, C. L.; Silvermyr, D.; Silvestre, C.; Sim, K. S.; Singh, B. K.; Singh, C. P.; Singh, V.; Skolnik, M.; Slunečka, M.; Solano, S.; Soltz, R. A.; Sondheim, W. E.; Sorensen, S. P.; Sourikova, I. V.; Sparks, N. A.; Stankus, P. W.; Steinberg, P.; Stenlund, E.; Stepanov, M.; Ster, A.; Stoll, S. P.; Sugitate, T.; Sukhanov, A.; Sun, J.; Sziklai, J.; Takagui, E. M.; Takahara, A.; Taketani, A.; Tanabe, R.; Tanaka, Y.; Taneja, S.; Tanida, K.; Tannenbaum, M. J.; Tarafdar, S.; Taranenko, A.; Tarján, P.; Tennant, E.; Themann, H.; Thomas, T. L.; Todoroki, T.; Togawa, M.; Toia, A.; Tomášek, L.; Tomášek, M.; Torii, H.; Towell, R. S.; Tserruya, I.; Tsuchimoto, Y.; Tsuji, T.; Vale, C.; Valle, H.; van Hecke, H. W.; Vargyas, M.; Vazquez-Zambrano, E.; Veicht, A.; Velkovska, J.; Vértesi, R.; Vinogradov, A. A.; Virius, M.; Voas, B.; Vossen, A.; Vrba, V.; Vznuzdaev, E.; Wang, X. R.; Watanabe, D.; Watanabe, K.; Watanabe, Y.; Watanabe, Y. S.; Wei, F.; Wei, R.; Wessels, J.; Whitaker, S.; White, S. N.; Winter, D.; Wolin, S.; Wood, J. P.; Woody, C. L.; Wright, R. M.; Wysocki, M.; Xia, B.; Xie, W.; Yamaguchi, Y. L.; Yamaura, K.; Yang, R.; Yanovich, A.; Ying, J.; Yokkaichi, S.; You, Z.; Young, G. R.; Younus, I.; Yushmanov, I. E.; Zajc, W. A.; Zelenski, A.; Zhang, C.; Zhou, S.; Zolin, L.; Phenix Collaboration

    2016-01-01

    We report the measurement of cumulants (Cn,n =1 ,...,4 ) of the net-charge distributions measured within pseudorapidity (|η |<0.35 ) in Au +Au collisions at √{sNN}=7.7 -200 GeV with the PHENIX experiment at the Relativistic Heavy Ion Collider. The ratios of cumulants (e.g., C1/C2 , C3/C1 ) of the net-charge distributions, which can be related to volume independent susceptibility ratios, are studied as a function of centrality and energy. These quantities are important to understand the quantum-chromodynamics phase diagram and possible existence of a critical end point. The measured values are very well described by expectation from negative binomial distributions. We do not observe any nonmonotonic behavior in the ratios of the cumulants as a function of collision energy. The measured values of C1/C2 and C3/C1 can be directly compared to lattice quantum-chromodynamics calculations and thus allow extraction of both the chemical freeze-out temperature and the baryon chemical potential at each center-of-mass energy. The extracted baryon chemical potentials are in excellent agreement with a thermal-statistical analysis model.

  1. Relationship between cumulative BMI and symptomatic, psychosocial, and medical outcomes in patients with borderline personality disorder.

    Science.gov (United States)

    Frankenburg, Frances R; Zanarini, Mary C

    2011-08-01

    We examined the relationship between cumulative body mass index (BMI) and symptomatic, psychosocial, and medical outcomes in patients with borderline personality disorder (BPD). Two hundred female borderline patients were weighed and measured during their index admission. They were subsequently interviewed at six-, eight-, and 10-year intervals. Over 10 years of prospective follow-up, increases in cumulative BMI were significantly associated with self-mutilation and dissociation (but not suicide attempts). Increases in cumulative BMI were also significantly associated with having no life partner, a poor work or school history, being on disability, being rated with a GAF score in the fair or poor range, and having a low income. In addition, increases in BMI were related to having two or more other medical conditions and using costly forms of health care. Increases in cumulative BMI may be a marker for adverse symptomatic, functional, and medical outcomes in patients with BPD.

  2. Deliberative Democracy, Institution Building, and the Pragmatics of Cumulative Effects Assessment

    Directory of Open Access Journals (Sweden)

    John R. Parkins

    2011-09-01

    Full Text Available Cumulative effects assessment is a process of scientific analysis, social choice, and public policy development, yet the linkages among these domains are often less than transparent. Limits to scientific and technical assessment, issues of power and control of information, and episodic forms of civic engagement represent serious challenges to meaningful understanding of cumulative effects assessment and land-use planning. In articulating these challenges, I draw on case studies from Ontario's Lands for Life and Alberta's Land-use Framework to illustrate current limitations to cumulative effects assessment on public lands in Canada. As a partial remedy for these limitations, insights into a pragmatic approach to impact assessment, in contrast to decisionistic and technocratic approaches, offer a way forward through a more robust integration of scientific information, civic engagement, and public policy development. I also identify a need for longer-standing institutions that are dedicated to regional planning and cumulative effects assessment in Canada.

  3. TESTING FOR DIFFERENCES BETWEEN CUMULATIVE DISTRIBUTION FUNCTIONS FROM COMPLEX ENVIRONMENTAL SAMPLING SURVEYS

    Science.gov (United States)

    The U.S. Environmental Protection Agency's Environmental Monitoring and Assessment Program (EMAP) employs the cumulative distribution function (cdf) to measure the status of quantitative variables for resources of interest. The ability to compare cdf's for a resource from, say,...

  4. Statistical Methods for Estimating the Cumulative Risk of Screening Mammography Outcomes

    NARCIS (Netherlands)

    Hubbard, R.A.; Ripping, T.M.; Chubak, J.; Broeders, M.J.; Miglioretti, D.L.

    2016-01-01

    BACKGROUND: This study illustrates alternative statistical methods for estimating cumulative risk of screening mammography outcomes in longitudinal studies. METHODS: Data from the US Breast Cancer Surveillance Consortium (BCSC) and the Nijmegen Breast Cancer Screening Program in the Netherlands were

  5. Evaluating Cumulative Ecosystem Response to Restoration Projects in the Columbia River Estuary, Annual Report 2007

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, Gary E.; Diefenderfer, Heida L.; Borde, Amy B.; Dawley, Earl M.; Ebberts, Blaine D.; Putman, Douglas A.; Roegner, G. C.; Russell, Micah; Skalski, John R.; Thom, Ronald M.; Vavrinec, John

    2008-10-01

    The goal of this multi-year study (2004-2010) is to develop a methodology to evaluate the cumulative effects of multiple habitat restoration projects intended to benefit ecosystems supporting juvenile salmonids in the lower Columbia River and estuary. Literature review in 2004 revealed no existing methods for such an evaluation and suggested that cumulative effects could be additive or synergistic. Field research in 2005, 2006, and 2007 involved intensive, comparative studies paired by habitat type (tidal swamp vs. marsh), trajectory (restoration vs. reference site), and restoration action (tide gate vs. culvert vs. dike breach). The field work established two kinds of monitoring indicators for eventual cumulative effects analysis: core and higher-order indicators. Management implications of limitations and applications of site-specific effectiveness monitoring and cumulative effects analysis were identified.

  6. The seemingly quixotic pursuit of a cumulative psychological science: introduction to the special issue.

    Science.gov (United States)

    Curran, Patrick J

    2009-06-01

    The goal of any empirical science is to pursue the construction of a cumulative base of knowledge upon which the future of the science may be built. However, there is mixed evidence that the science of psychology can accurately be characterized by such a cumulative progression. Indeed, some argue that the development of a truly cumulative psychological science is not possible with the current paradigms of hypothesis testing in single-study designs. The author explores this controversy as a framework to introduce the 6 articles that make up this special issue on the integration of data and empirical findings across multiple studies. The author proposes that the methods and techniques described in this set of articles can significantly propel researchers forward in their ongoing quest to build a cumulative psychological science. (PsycINFO Database Record (c) 2009 APA, all rights reserved).

  7. CUMULATIVE DISTRIBUTION FUNCTIONS FOR THE TEMPERATURE THRESHOLD FOR THE ONSET OF CARBON STEEL CORROSION

    Energy Technology Data Exchange (ETDEWEB)

    K.G. Mon

    1998-05-15

    The purpose of this calculation is to process the cumulative distribution functions (CDFs) characterizing the temperature threshold for the onset of corrosion provided by expert elicitation and minimize the set of values to 200 points for use in WAPDEG.

  8. Cumulative Phenomena through the Quark-Parton Diagram Summation at Thresholds

    CERN Document Server

    Braun, M A

    1998-01-01

    A microscopic treatment of cumulative phenomena based on perturbative QCD calculations of the corresponding quark diagrams near the threshold is presented. To sum all diagrams like these the special technique based on the recurrence relations was developed. The x-behaviour of the nuclear structure function $F_{2}(x)$ in the cumulative region x>1 was found to be roughly exponential, governed by an effective coupling constant, which depends on the QCD coupling constant and quark mass. Two mechanisms for cumulative particle production, direct and spectator ones, were analysed. It was shown that due to final state interactions the leading terms of the direct mechanism contribution are cancelled and the spectator mechanism is the dominant one. It leads to a smaller slope of the particle production rates compared to the slope of the nuclear structure function in the cumulative region, in agreement with the recent experimental data. The slope difference is due to additional multiple interactions between nuclear and ...

  9. Aerospace Medicine and Biology: A cumulative index to the 1980 issues

    Science.gov (United States)

    1981-01-01

    A cumulative index to the abstracts contained in the Supplements 203 through 214 of Aerospace Medicine and Biology: A Continuing Bibliography is presented. It includes three indexes--subject, personal author, and corporate source.

  10. Mapping cumulative environmental effects, social vulnerability, and health in the San Joaquin Valley, California.

    Science.gov (United States)

    Huang, Ganlin; London, Jonathan

    2012-05-01

    To understand the social distribution of environmental hazards, methods to assess cumulative effects and their health implications are needed. We developed a cumulative environmental hazard index integrating environmental data on pollution sites, air quality, and pesticide use; a social vulnerability index to measure residents' resources to prevent or mitigate health effects; and a health index. We found that communities in California's San Joaquin Valley with high social vulnerability face more environmental burdens and have worse health conditions.

  11. Cumulative Incidence of Cancer among People with AIDS in the United States

    Science.gov (United States)

    Simard, Edgar P.; Pfeiffer, Ruth M.; Engels, Eric A.

    2010-01-01

    BACKGROUND As people with acquired immunodeficiency syndrome (AIDS) live longer due to highly active antiretroviral therapy (HAART, widely available since 1996), the overall burden of cancer may increase. METHODS A population-based record linkage study identified cancers in 472,378 people with AIDS (1980–2006). Using non-parametric competing risk methods, we estimated cumulative incidence of cancer across 3 calendar periods (AIDS onset in 1980–1989, 1990–1995, and 1996–2006). RESULTS Measured at 5-years after AIDS onset, cumulative incidence of AIDS-defining cancer (ADC) declined sharply across AIDS calendar periods (from 18% in 1980–1989, to 11% in 1990–1995, to 4.2% in 1996–2006 [i.e., HAART era]). Cumulative incidence of Kaposi sarcoma declined from 14.3% during 1980–1989 to 6.7% during 1990–1995 to 1.8% during 1996–2006. Non-Hodgkin lymphoma (NHL) cumulative incidence declined from 3.8% during 1990–1995 to 2.2% during 1996–2006; during the HAART era, NHL was the commonest (53%) ADC. Cumulative incidence of non-AIDS-defining cancer (NADC) increased from 1.1% to 1.5% with no change thereafter (1.0%, 1996–2006), in part due to declines in competing mortality. However, cumulative incidence increased steadily over time for specific NADCs (anal cancer, Hodgkin lymphoma, and liver cancer). Lung cancer cumulative incidence increased from 0.14% during 1980–1989 to 0.32% during 1990–1995, with no change thereafter. CONCLUSIONS We noted dramatically declining cumulative incidence of 2 major ADCs (Kaposi sarcoma and NHL) and increases in some NADCs (specifically cancers of the anus, liver, and lung, and Hodgkin lymphoma). As HIV/AIDS is increasingly managed as a chronic disease, greater attention should be focused on cancer screening and prevention. PMID:20960504

  12. Radiation optic neuropathy and retinopathy with low dose (20 Gy radiation treatment

    Directory of Open Access Journals (Sweden)

    Crandall E. Peeler

    2016-10-01

    Conclusions and importance: Though cumulative radiation doses to the anterior visual pathway of less than 50 Gy are traditionally felt to be safe, it is important to consider not just the total exposure but also the size of individual fractions. The single-dose threshold for RON in proton beam treatment has yet to be defined. Our case suggests that fractions of less than 10 Gy should be delivered to minimize the risk of optic nerve injury.

  13. The Challenge of Developing Social Indicators for Cumulative Effects Assessment and Land Use Planning

    Directory of Open Access Journals (Sweden)

    John R. Parkins

    2011-06-01

    Full Text Available This paper provides a synopsis on social indicators as relevant to cumulative effects assessment and land use planning. Although much has been done to better understand the social dimensions of environmental assessment, empirical work has been lacking on social indicators that could be used either as measurable inputs or outputs for cumulative effects assessment and land use planning in different kinds of communities and regions. Cumulative effects models currently in practice often fail to address deeper issues of community and regional well-being. Against this gap, social scientists are being asked to make reliable generalizations about functional, measurable relationships between certain social indicators and land use change or scenarios. To address this challenge, the Alberta Research Council held a two-day workshop in 2005 with social scientists. The workshop resulted in a list of prioritized social indicators that could be included in cumulative effects modeling/assessments and land use planning. The top five social indicators included population growth rate, education attainment, self-assessed quality of life, equity, i.e., distribution of benefits, and locus of control. Although consensus on social indicators and social thresholds for cumulative effects models was not reached, the insight gained from the workshop will help inform future cumulative effects assessment and land use planning.

  14. Assessing the cumulative impact of disturbance on canopy structure and chemistry in Appalachian forests

    Science.gov (United States)

    Deel, Lindsay N.

    Eastern forests experience a range of disturbance events over time, from stand-replacing disturbances, such as clear cuts, to ephemeral disturbances, such as insect outbreaks. By understanding the cumulative impact of disturbances on canopy structure and chemistry, we can gain insight into management strategies, assess a variety of ecosystem services, and even contribute to a larger body of knowledge on global climate change. I transformed a series of Landsat images spanning approximately 25 years into cumulative disturbance maps covering Green Ridge State Forest and Savage River State Forest in western Maryland. Intensive field surveys collected during the summer of 2009 provided measurements of canopy N and estimates of canopy cover, understory cover, and leaf cover. I used AVIRIS imagery flown concurrently with field data collection to map canopy nitrogen across both forests. Through this project, I tested the impact of cumulative disturbance on forest canopy cover and canopy nitrogen. I found that increased values of cumulative disturbance had a measurable negative impact on forest canopy structure and canopy nitrogen. Moreover, by testing varying methods of summing cumulative disturbance, I found that past disturbances diminish over time in importance, yet still influence the current canopy structure and canopy N of a forest. Thus, my study suggests that Landsat time series data can be synthesized into cumulative metrics incorporating multiple disturbance types, which help explain important disturbance-mediated changes in ecosystem functions.

  15. Evaluation of various approaches for assessing dose indicators and patient organ doses resulting from radiotherapy cone-beam CT

    Energy Technology Data Exchange (ETDEWEB)

    Rampado, Osvaldo, E-mail: orampado@cittadellasalute.to.it; Giglioli, Francesca Romana; Rossetti, Veronica; Ropolo, Roberto [Struttura Complessa Fisica Sanitaria, Azienda Ospedaliero Universitaria Città della Salute e della Scienza, Corso Bramante 88, Torino 10126 (Italy); Fiandra, Christian; Ragona, Riccardo [Radiation Oncology Department, University of Turin, Torino 10126 (Italy)

    2016-05-15

    Purpose: The aim of this study was to evaluate various approaches for assessing patient organ doses resulting from radiotherapy cone-beam CT (CBCT), by the use of thermoluminescent dosimeter (TLD) measurements in anthropomorphic phantoms, a Monte Carlo based dose calculation software, and different dose indicators as presently defined. Methods: Dose evaluations were performed on a CBCT Elekta XVI (Elekta, Crawley, UK) for different protocols and anatomical regions. The first part of the study focuses on using PCXMC software (PCXMC 2.0, STUK, Helsinki, Finland) for calculating organ doses, adapting the input parameters to simulate the exposure geometry, and beam dose distribution in an appropriate way. The calculated doses were compared to readouts of TLDs placed in an anthropomorphic Rando phantom. After this validation, the software was used for analyzing organ dose variability associated with patients’ differences in size and gender. At the same time, various dose indicators were evaluated: kerma area product (KAP), cumulative air-kerma at the isocenter (K{sub air}), cone-beam dose index, and central cumulative dose. The latter was evaluated in a single phantom and in a stack of three adjacent computed tomography dose index phantoms. Based on the different dose indicators, a set of coefficients was calculated to estimate organ doses for a range of patient morphologies, using their equivalent diameters. Results: Maximum organ doses were about 1 mGy for head and neck and 25 mGy for chest and pelvis protocols. The differences between PCXMC and TLDs doses were generally below 10% for organs within the field of view and approximately 15% for organs at the boundaries of the radiation beam. When considering patient size and gender variability, differences in organ doses up to 40% were observed especially in the pelvic region; for the organs in the thorax, the maximum differences ranged between 20% and 30%. Phantom dose indexes provided better correlation with organ

  16. The effects of increased constant incubation temperature and cumulative acute heat shock exposures on morphology and survival of Lake Whitefish (Coregonus clupeaformis) embryos.

    Science.gov (United States)

    Lee, Abigail H; Eme, John; Mueller, Casey A; Manzon, Richard G; Somers, Christopher M; Boreham, Douglas R; Wilson, Joanna Y

    2016-04-01

    Increasing incubation temperatures, caused by global climate change or thermal effluent from industrial processes, may influence embryonic development of fish. This study investigates the cumulative effects of increased incubation temperature and repeated heat shocks on developing Lake Whitefish (Coregonus clupeaformis) embryos. We studied the effects of three constant incubation temperatures (2°C, 5°C or 8°C water) and weekly, 1-h heat shocks (+3°C) on hatching time, survival and morphology of embryos, as these endpoints may be particularly susceptible to temperature changes. The constant temperatures represent the predicted magnitude of elevated water temperatures from climate change and industrial thermal plumes. Time to the pre-hatch stage decreased as constant incubation temperature increased (148d at 2°C, 92d at 5°C, 50d at 8°C), but weekly heat shocks did not affect time to hatch. Mean survival rates and embryo morphometrics were compared at specific developmental time-points (blastopore, eyed, fin flutter and pre-hatch) across all treatments. Constant incubation temperatures or +3°C heat-shock exposures did not significantly alter cumulative survival percentage (~50% cumulative survival to pre-hatch stage). Constant warm incubation temperatures did result in differences in morphology in pre-hatch stage embryos. 8°C and 5°C embryos were significantly smaller and had larger yolks than 2°C embryos, but heat-shocked embryos did not differ from their respective constant temperature treatment groups. Elevated incubation temperatures may adversely alter Lake Whitefish embryo size at hatch, but weekly 1-h heat shocks did not affect size or survival at hatch. These results suggest that intermittent bouts of warm water effluent (e.g., variable industrial emissions) are less likely to negatively affect Lake Whitefish embryonic development than warmer constant incubation temperatures that may occur due to climate change.

  17. Variability of marker-based rectal dose evaluation in HDR cervical brachytherapy.

    Science.gov (United States)

    Wang, Zhou; Jaggernauth, Wainwright; Malhotra, Harish K; Podgorsak, Matthew B

    2010-01-01

    In film-based intracavitary brachytherapy for cervical cancer, position of the rectal markers may not accurately represent the anterior rectal wall. This study was aimed at analyzing the variability of rectal dose estimation as a result of interfractional variation of marker placement. A cohort of five patients treated with multiple-fraction tandem and ovoid high-dose-rate (HDR) brachytherapy was studied. The cervical os point and the orientation of the applicators were matched among all fractional plans for each patient. Rectal points obtained from all fractions were then input into each clinical treated plan. New fractional rectal doses were obtained and a new cumulative rectal dose for each patient was calculated. The maximum interfractional variation of distances between rectal dose points and the closest source positions was 1.1 cm. The corresponding maximum variability of fractional rectal dose was 65.5%. The percentage difference in cumulative rectal dose estimation for each patient was 5.4%, 19.6%, 34.6%, 23.4%, and 13.9%, respectively. In conclusion, care should be taken when using rectal markers as reference points for estimating rectal dose in HDR cervical brachytherapy. The best estimate of true rectal dose for each fraction should be determined by the most anterior point among all fractions.

  18. Cumulative Stress and Cortisol Disruption among Black and Hispanic Pregnant Women in an Urban Cohort

    Science.gov (United States)

    Suglia, Shakira Franco; Staudenmayer, John; Cohen, Sheldon; Enlow, Michelle Bosquet; Rich-Edwards, Janet W.; Wright, Rosalind J.

    2010-01-01

    While adult hypothalamic-pituitary-adrenocortical (HPA) axis functioning is thought to be altered by traumatic experiences, little data exist on the effects of cumulative stress on HPA functioning among pregnant women or among specific racial and ethnic groups. Individuals may be increasingly vulnerable to physiological alterations when experiencing cumulative effects of multiple stressors. These effects may be particularly relevant in urban poor communities where exposure to multiple stressors is more prevalent. The goal of this study was to explore the effects of multiple social stressors on HPA axis functioning in a sample of urban Black (n = 68) and Hispanic (n = 132) pregnant women enrolled in the Asthma Coalition on Community, Environment, and Social Stress (ACCESS). Pregnant women were administered the Revised Conflict Tactics Scale (R-CTS) survey to assess interpersonal violence, the Experiences of Discrimination (EOD) survey, the Crisis in Family Systems-Revised (CRISYS-R) negative life events survey, and the My Exposure to Violence (ETV) survey, which ascertains exposure to community violence. A cumulative stress measure was derived from these instruments. Salivary cortisol samples were collected five times per day over three days to assess area under the curve (AUC), morning change, and basal awakening response in order to characterize diurnal salivary cortisol patterns. Repeated measures mixed models, stratified by race/ethnicity, were performed adjusting for education level, age, smoking status, body mass index and weeks pregnant at time of cortisol sampling. The majority of Hispanic participants (57%) had low cumulative stress exposure, while the majority of Black participants had intermediate (35%) or high (41%) cumulative stress exposure. Results showed that among Black but not Hispanic women, cumulative stress was associated with lower morning cortisol levels, including a flatter waking to bedtime rhythm. These analyses suggest that the combined

  19. Cumulative Stress and Cortisol Disruption among Black and Hispanic Pregnant Women in an Urban Cohort.

    Science.gov (United States)

    Suglia, Shakira Franco; Staudenmayer, John; Cohen, Sheldon; Enlow, Michelle Bosquet; Rich-Edwards, Janet W; Wright, Rosalind J

    2010-12-01

    While adult hypothalamic-pituitary-adrenocortical (HPA) axis functioning is thought to be altered by traumatic experiences, little data exist on the effects of cumulative stress on HPA functioning among pregnant women or among specific racial and ethnic groups. Individuals may be increasingly vulnerable to physiological alterations when experiencing cumulative effects of multiple stressors. These effects may be particularly relevant in urban poor communities where exposure to multiple stressors is more prevalent. The goal of this study was to explore the effects of multiple social stressors on HPA axis functioning in a sample of urban Black (n = 68) and Hispanic (n = 132) pregnant women enrolled in the Asthma Coalition on Community, Environment, and Social Stress (ACCESS). Pregnant women were administered the Revised Conflict Tactics Scale (R-CTS) survey to assess interpersonal violence, the Experiences of Discrimination (EOD) survey, the Crisis in Family Systems-Revised (CRISYS-R) negative life events survey, and the My Exposure to Violence (ETV) survey, which ascertains exposure to community violence. A cumulative stress measure was derived from these instruments. Salivary cortisol samples were collected five times per day over three days to assess area under the curve (AUC), morning change, and basal awakening response in order to characterize diurnal salivary cortisol patterns. Repeated measures mixed models, stratified by race/ethnicity, were performed adjusting for education level, age, smoking status, body mass index and weeks pregnant at time of cortisol sampling. The majority of Hispanic participants (57%) had low cumulative stress exposure, while the majority of Black participants had intermediate (35%) or high (41%) cumulative stress exposure. Results showed that among Black but not Hispanic women, cumulative stress was associated with lower morning cortisol levels, including a flatter waking to bedtime rhythm. These analyses suggest that the combined

  20. Cell death following thermal neutron exposure

    Energy Technology Data Exchange (ETDEWEB)

    Paterson, L.C. [Canadian Nuclear Laboratories, Chalk River, Ontario (Canada); Atanackovic, J. [Ontario Power Generation, Toronto, Ontario (Canada); Boyer, C. [Canadian Neutron Beam Centre, Chalk River, Ontario (Canada); El-Jaby, S.; Priest, N.D. [Canadian Nuclear Laboratories, Chalk River, Ontario (Canada); Seymour, C.B.; Boreham, D.R. [McMaster Univ., Hamilton, Ontario (Canada); Richardson, R.B. [Canadian Nuclear Laboratories, Chalk River, Ontario (Canada)

    2014-07-01

    When individuals are exposed to unknown external ionizing radiation, it is desirable to have the means to assess both the absorbed dose received (Gy) and the radiation quality. Yet, conventional biodosimetry techniques, specifically the dicentric chromosome assay, cannot differentiate between the damage caused by high- and low-linear energy transfer (LET) exposures. Frequencies of apoptosis and necrosis, may provide an alternative method that assesses both the absorbed dose and radiation quality after unknown exposures. For this preliminary study, human lymphocytes were irradiated with {sup 60}Co gamma rays and thermal neutrons. Both apoptosis and necrosis increased with increasing gamma dose. In contrast, no dose-response was observed following thermal neutron exposure at doses up to 2.61 Gy. (author)

  1. Cumulative health risk assessment of 17 perfluoroalkylated and polyfluoroalkylated substances (PFASs) in the Swedish population.

    Science.gov (United States)

    Borg, Daniel; Lund, Bert-Ove; Lindquist, Nils-Gunnar; Håkansson, Helen

    2013-09-01

    Humans are simultaneously exposed to a multitude of chemicals. Human health risk assessment of chemicals is, however, normally performed on single substances, which may underestimate the total risk, thus bringing a need for reliable methods to assess the risk of combined exposure to multiple chemicals. Per- and polyfluoroalkylated substances (PFASs) is a large group of chemicals that has emerged as global environmental contaminants. In the Swedish population, 17 PFASs have been measured, of which the vast majority lacks human health risk assessment information. The objective of this study was to for the first time perform a cumulative health risk assessment of the 17 PFASs measured in the Swedish population, individually and in combination, using the Hazard Index (HI) approach. Swedish biomonitoring data (blood/serum concentrations of PFASs) were used and two study populations identified: 1) the general population exposed indirectly via the environment and 2) occupationally exposed professional ski waxers. Hazard data used were publicly available toxicity data for hepatotoxicity and reproductive toxicity as well as other more sensitive toxic effects. The results showed that PFASs concentrations were in the low ng/ml serum range in the general population, reaching high ng/ml and low μg/ml serum concentrations in the occupationally exposed. For those congeners lacking toxicity data with regard to hepatotoxicity and reproductive toxicity read-across extrapolations was performed. Other effects at lower dose levels were observed for some well-studied congeners. The risk characterization showed no concern for hepatotoxicity or reproductive toxicity in the general population except in a subpopulation eating PFOS-contaminated fish, illustrating that high local exposure may be of concern. For the occupationally exposed there was concern for hepatotoxicity by PFOA and all congeners in combination as well as for reproductive toxicity by all congeners in combination, thus a

  2. Thermal comfort

    DEFF Research Database (Denmark)

    d’Ambrosio Alfano, Francesca Romana; Olesen, Bjarne W.; Palella, Boris Igor;

    2014-01-01

    Thermal comfort is one of the most important aspects of the indoor environmental quality due to its effects on well-being, people's performance and building energy requirements. Its attainment is not an easy task requiring advanced design and operation of building and HVAC systems, taking...... into account all parameters involved. Even though thermal comfort fundamentals are consolidated topics for more than forty years, often designers seem to ignore or apply them in a wrong way. Design input values from standards are often considered as universal values rather than recommended values to be used...... under specific conditions. At operation level, only few variables are taken into account with unpredictable effects on the assessment of comfort indices. In this paper, the main criteria for the design and assessment of thermal comfort are discussed in order to help building and HVAC systems designers...

  3. Long-term cardiac follow-up of children treated with anthracycline doses of 300 mg/m2 or less for acute lymphoblastic leukemia

    DEFF Research Database (Denmark)

    Rathe, Mathias; Carlsen, Niels Lauritz Torp; Oxhøj, Henrik;

    2010-01-01

    The cardiotoxic effect of anthracyclines has been well described for moderate to high cumulative doses (>350 mg/m(2)). However, the question of whether sub-clinical signs of cardiomyopathy may develop and progress over time in children receiving doses of...

  4. A method proposal for cumulative environmental impact assessment based on the landscape vulnerability evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Pavlickova, Katarina; Vyskupova, Monika, E-mail: vyskupova@fns.uniba.sk

    2015-01-15

    Cumulative environmental impact assessment deals with the occasional use in practical application of environmental impact assessment process. The main reasons are the difficulty of cumulative impact identification caused by lack of data, inability to measure the intensity and spatial effect of all types of impacts and the uncertainty of their future evolution. This work presents a method proposal to predict cumulative impacts on the basis of landscape vulnerability evaluation. For this purpose, qualitative assessment of landscape ecological stability is conducted and major vulnerability indicators of environmental and socio-economic receptors are specified and valuated. Potential cumulative impacts and the overall impact significance are predicted quantitatively in modified Argonne multiple matrixes while considering the vulnerability of affected landscape receptors and the significance of impacts identified individually. The method was employed in the concrete environmental impact assessment process conducted in Slovakia. The results obtained in this case study reflect that this methodology is simple to apply, valid for all types of impacts and projects, inexpensive and not time-consuming. The objectivity of the partial methods used in this procedure is improved by quantitative landscape ecological stability evaluation, assignment of weights to vulnerability indicators based on the detailed characteristics of affected factors, and grading impact significance. - Highlights: • This paper suggests a method proposal for cumulative impact prediction. • The method includes landscape vulnerability evaluation. • The vulnerability of affected receptors is determined by their sensitivity. • This method can increase the objectivity of impact prediction in the EIA process.

  5. Investigating the effect among size, growth opportunity and cumulative abnormal returns of the companies

    Directory of Open Access Journals (Sweden)

    Khalil bevali behbahani

    2016-09-01

    Full Text Available The stockholders and investors require identifying main variables that explain stock return. Being aware of variables and achieving an appropriate model can lead to improve their investment and considering that each wise and economic person’s goal is obtain high and more returns, the current research is sought to investigate the effect of company’s characteristics and the ratio of investment on company’s cumulative abnormal returns. Statistical sample which has been used in current research includes 256 listed companies in Tehran Stock Exchange during 2002 to 2013. Dependent variable of current research is cumulative abnormal return. The independent variables whose effects are investigated on cumulative abnormal return include company’s size, growth opportunity. The data are collected and were inserted in Excel file as information database. Testing hypotheses also has been done from multi-variable regression models based on combined data technique using econometric software Eviews. The findings of the research show that there is a positive and significant relationship between company’s size and company’s cumulative abnormal return. There is also a negative and significant relationship between growth opportunities and company’s cumulative abnormal return.

  6. Evaluating Cumulative Ecosystem Response to Restoration Projects in the Lower Columbia River and Estuary, 2009

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, Gary E.; Diefenderfer, Heida L.; Borde, Amy B.; Bryson, Amanda J.; Cameron, April; Coleman, Andre M.; Corbett, C.; Dawley, Earl M.; Ebberts, Blaine D.; Kauffman, Ronald; Roegner, G. Curtis; Russell, Micah T.; Silva, April; Skalski, John R.; Thom, Ronald M.; Vavrinec, John; Woodruff, Dana L.; Zimmerman, Shon A.

    2010-10-26

    This is the sixth annual report of a seven-year project (2004 through 2010) to evaluate the cumulative effects of habitat restoration actions in the lower Columbia River and estuary (LCRE). The project, called the Cumulative Effects Study, is being conducted for the U.S. Army Corps of Engineers Portland District (USACE) by the Marine Sciences Laboratory of the Pacific Northwest National Laboratory (PNNL), the Pt. Adams Biological Field Station of the National Marine Fisheries Service (NMFS), the Columbia River Estuary Study Taskforce (CREST), and the University of Washington. The goal of the Cumulative Effects Study is to develop a methodology to evaluate the cumulative effects of multiple habitat restoration projects intended to benefit ecosystems supporting juvenile salmonids in the 235-km-long LCRE. Literature review in 2004 revealed no existing methods for such an evaluation and suggested that cumulative effects could be additive or synergistic. From 2005 through 2009, annual field research involved intensive, comparative studies paired by habitat type (tidal swamp versus marsh), trajectory (restoration versus reference site), and restoration action (tidegate replacement vs. culvert replacement vs. dike breach).

  7. Assessing the cumulative environmental effects of marine renewable energy developments: Establishing common ground.

    Science.gov (United States)

    Willsteed, Edward; Gill, Andrew B; Birchenough, Silvana N R; Jude, Simon

    2017-01-15

    Assessing and managing the cumulative impacts of human activities on the environment remains a major challenge to sustainable development. This challenge is highlighted by the worldwide expansion of marine renewable energy developments (MREDs) in areas already subject to multiple activities and climate change. Cumulative effects assessments in theory provide decision makers with adequate information about how the environment will respond to the incremental effects of licensed activities and are a legal requirement in many nations. In practise, however, such assessments are beset by uncertainties resulting in substantial delays during the licensing process that reduce MRED investor confidence and limit progress towards meeting climate change targets. In light of these targets and ambitions to manage the marine environment sustainably, reducing the uncertainty surrounding MRED effects and cumulative effects assessment are timely and vital. This review investigates the origins and evolution of cumulative effects assessment to identify why the multitude of approaches and pertinent research have emerged, and discusses key considerations and challenges relevant to assessing the cumulative effects of MREDs and other activities on ecosystems. The review recommends a shift away from the current reliance on disparate environmental impact assessments and limited strategic environmental assessments, and a move towards establishing a common system of coordinated data and research relative to ecologically meaningful areas, focussed on the needs of decision makers tasked with protecting and conserving marine ecosystems and services.

  8. Radiation doses received by premature babies in the neonatal intensive care unit; Doses d'irradiation recues par les prematures en service de reanimation

    Energy Technology Data Exchange (ETDEWEB)

    Thierry-Chef, I.; Maccia, C. [Centre d' Assurance de Qualite des Applications Technologiques dans le Domaine de la Sante, 92 - Bourg la Reine (France); Thierry-Chef, I.; Laurier, D.; Tirmarche, M. [Institut de Radioprotection et de Surete Nucleaire (IRSN/DRPH/SRBE/LRPID), 92 - Fontenay-aux-Roses (France); Costil, J. [Hopital Armand Trousseau, Service de Reanimation Neonatale, 75 - Paris (France)

    2005-02-15

    Purpose. Because of frequent radiological investigations performed in 1 neonatal intensive care unit, a dosimetry study was carried out to assess the level of doses received by premature babies. Materials and methods. In vivo measurements were performed and effective doses were evaluated for single radiographs. Individual cumulative doses received over the period of stay were then estimated, for each premature baby entering the intensive care unit in 2002, taking into account the number of radiographs they underwent. Results. On average, babies stayed for a week and more than one radio-graph was taken per day. Results showed that, even if average doses per radiograph were relatively low (25{mu}Sv), cumulative doses strongly depended on the length of stay, and can reach a few mSv. Conclusion. Even if doses per radiograph are in agreement with European recommendations, optimisation of doses is particularly important because premature babies are more sensitive to radiation than adults and because they usually undergo further radiological examinations in other services. On the basis of the results of this dosimetry study, the implementation of a larger study is being discussed. (author)

  9. Matrix Thermalization

    CERN Document Server

    Craps, Ben; Nguyen, Kévin

    2016-01-01

    Matrix quantum mechanics offers an attractive environment for discussing gravitational holography, in which both sides of the holographic duality are well-defined. Similarly to higher-dimensional implementations of holography, collapsing shell solutions in the gravitational bulk correspond in this setting to thermalization processes in the dual quantum mechanical theory. We construct an explicit, fully nonlinear supergravity solution describing a generic collapsing dilaton shell, specify the holographic renormalization prescriptions necessary for computing the relevant boundary observables, and apply them to evaluating thermalizing two-point correlation functions in the dual matrix theory.

  10. Thermal Expansion of Irradiated Polytetrafluoroethylene

    OpenAIRE

    Subrahmanyam, HN; Subramanyam, SV

    1987-01-01

    The thermal expansion coefficient of gamma-irradiated Polytetrafluoroethylene (PTFE) has been measured in the temperature range 80-340 K by using a three-terminal capacitance technique. The samples are irradiated in air at room temperature with gamma rays from a $Co^{60}$ source at a dose rate of 0.26 Mrad/h. The change in crystallinity is measured by an x-ray technique. The expansion coefficient is found to increase with radiation dose below 140 K owing to the predominant effect of degradati...

  11. Dose and dose rate effects of whole-body gamma-irradiation: II. Hematological variables and cytokines

    Science.gov (United States)

    Gridley, D. S.; Pecaut, M. J.; Miller, G. M.; Moyers, M. F.; Nelson, G. A.

    2001-01-01

    The goal of part II of this study was to evaluate the effects of gamma-radiation on circulating blood cells, functional characteristics of splenocytes, and cytokine expression after whole-body irradiation at varying total doses and at low- and high-dose-rates (LDR, HDR). Young adult C57BL/6 mice (n = 75) were irradiated with either 1 cGy/min or 80 cGy/min photons from a 60Co source to cumulative doses of 0.5, 1.5, and 3.0 Gy. The animals were euthanized at 4 days post-exposure for in vitro assays. Significant dose- (but not dose-rate-) dependent decreases were observed in erythrocyte and blood leukocyte counts, hemoglobin, hematocrit, lipopolysaccharide (LPS)-induced 3H-thymidine incorporation, and interleukin-2 (IL-2) secretion by activated spleen cells when compared to sham-irradiated controls (p < 0.05). Basal proliferation of leukocytes in the blood and spleen increased significantly with increasing dose (p < 0.05). Significant dose rate effects were observed only in thrombocyte counts. Plasma levels of transforming growth factor-beta 1 (TGF-beta 1) and splenocyte secretion of tumor necrosis factor-alpha (TNF-alpha) were not affected by either the dose or dose rate of radiation. The data demonstrate that the responses of blood and spleen were largely dependent upon the total dose of radiation employed and that an 80-fold difference in the dose rate was not a significant factor in the great majority of measurements.

  12. The association of rectal equivalent dose in 2 Gy fractions (EQD2) to late rectal toxicity in locally advanced cervical cancer patients who were evaluated by rectosigmoidoscopy in Faculty of Medicine, Chiang Mai University

    Energy Technology Data Exchange (ETDEWEB)

    Tharavichtikul, Ekkasit; Chitapanarux, Taned; Chakrabandhu, Somvilai; Klunklin, Pitchayaponne; Onchan, Wimrak; Wanwilairat, Somsak; Chitapanarux, Imjai [Faculty of Medicine, Chiang Mai University, Chiang Mai (Thailand); Meungwong, Pooriwat [Lampang Cancer Hospital, Lampang (Thailand); Traisathit, Patrinee [Faculty of Science, Chiang Mai University, Chiang Mai (Thailand); Galalae, Razvan [aculty of Medicine, Christian-Albrechts University at Kiel, Kiei (Germany)

    2014-06-15

    To evaluate association between equivalent dose in 2 Gy (EQD2) to rectal point dose and gastrointestinal toxicity from whole pelvic radiotherapy (WPRT) and intracavitary brachytherapy (ICBT) in cervical cancer patients who were evaluated by rectosigmoidoscopy in Faculty of Medicine, Chiang Mai University. Retrospective study was designed for the patients with locally advanced cervical cancer, treated by radical radiotherapy from 2004 to 2009 and were evaluated by rectosigmoidoscopy. The cumulative doses of WPRT and ICBT to the maximally rectal point were calculated to the EQD2 and evaluated the association of toxicities. Thirty-nine patients were evaluated for late rectal toxicity. The mean cumulative dose in term of EQD2 to rectum was 64.2 Gy. Grade 1 toxicities were the most common findings. According to endoscopic exam, the most common toxicities were congested mucosa (36 patients) and telangiectasia (32 patients). In evaluation between rectal dose in EQD2 and toxicities, no association of cumulative rectal dose to rectal toxicity, except the association of cumulative rectal dose in EQD2 >65 Gy to late effects of normal tissue (LENT-SOMA) scale > or = grade 2 (p = 0.022; odds ratio, 5.312; 95% confidence interval, 1.269-22.244). The cumulative rectal dose in EQD2 >65 Gy have association with > or = grade 2 LENT-SOMA scale.

  13. Estimation of cumulative exposures to naphtha at an automobile fuel-injector manufacturing plant.

    Science.gov (United States)

    Rocskay, A Z; Robins, T G; Echeverria, D; Schork, M A; Seixas, N S; White, R F; Proctor, S P

    1993-09-01

    As part of an epidemiologic study of neuropsychological and renal effects of occupational exposure to organic solvents, estimates of cumulative exposure to naphtha were derived for workers at an automobile fuel-injector manufacturing plant. The approach to exposure estimation was relatively unusual in three respects: (1) a marked association between indoor naphtha air concentration and outdoor temperature was modeled and applied to detailed historical temperature data to calculate cumulative exposure estimates; (2) the large number of investigator-generated air samples allowed the use of analyses of variance to compare alternative job-grouping schemes; and (3) the young age of the plant and few process changes allowed for historical exposure estimates with a high degree of confidence. The derived estimates of cumulative exposure appear to offer a firm basis for epidemiologic analyses of exposure-health outcome relationships.

  14. Cumulative clinical pregnancy rates after COH and IUI in subfertile couples.

    Science.gov (United States)

    Farhi, Jacob; Orvieto, Raoul

    2010-07-01

    To evaluate the influence of female age and cause of infertility on the outcome of controlled ovarian hyperstimulation (COH) and intrauterine insemination (IUI), we studied 2717 COH cycles in 1035 subfertile couples. The cumulative clinical pregnancy rates were 39% and 58% after three and six COH cycles, respectively. The cumulative pregnancy rate significantly decreased with maternal age and differed by cause of infertility. The cumulative pregnancy rate continued to increase with an increase in COH cycle number up to the third, or forth cycle, in patients with mechanical and combined infertility, respectively, and in up to the second cycle in patients aged 40 years or more. These findings provide treatment guidelines for clinicians in determining the likelihood of treatment success and the point at which to proceed to the next treatment strategy.

  15. Identification of multiple inputs single output errors-in-variables system using cumulant

    Institute of Scientific and Technical Information of China (English)

    Haihui Long; Jiankang Zhao

    2014-01-01

    A higher-order cumulant-based weighted least square (HOCWLS) and a higher-order cumulant-based iterative least square (HOCILS) are derived for multiple inputs single output (MISO) errors-in-variables (EIV) systems from noisy input/output data. Whether the noises of the input/output of the system are white or colored, the proposed algorithms can be insensitive to these noises and yield unbiased estimates. To realize adaptive pa-rameter estimates, a higher-order cumulant-based recursive least square (HOCRLS) method is also studied. Convergence analy-sis of the HOCRLS is conducted by using the stochastic process theory and the stochastic martingale theory. It indicates that the parameter estimation error of HOCRLS consistently converges to zero under a generalized persistent excitation condition. The use-fulness of the proposed algorithms is assessed through numerical simulations.

  16. A CUMULATIVE FATIGUE DAMAGE RULE UNDER THE ALTERNATIVE OF CORROSION OR CYCLIC LOADING

    Institute of Scientific and Technical Information of China (English)

    W.X.Yao

    2007-01-01

    Fatigue damage increases with the applied loading cycles in a cumulative manner and the material deteriorates with the corrosion time. A cumulative fatigue damage rule under the alternative of corrosion or cyclic loading was proposed. The specimens of aluminum alloy LY12-CZ soaked in corrosive liquid for different times were tested under the constant amplitude cyclic loading to obtain S-N curves. The test was carried out to verify the proposed cumulative fatigue damage rule under the different combinations among corrosion time,loading level, and the cycle numbers. It was shown that the predicted residual fatigue lives showed a good agreement with the experimental results and the proposed rule was simple and can be easily adopted.

  17. Investigation of the cumulative diminution process using the Fibonacci method and fractional calculus

    Science.gov (United States)

    Buyukkilic, F.; Ok Bayrakdar, Z.; Demirhan, D.

    2016-02-01

    In this study, we investigate the cumulative diminution phenomenon for a physical quantity and a diminution process with a constant acquisition quantity in each step in a viscous medium. We analyze the existence of a dynamical mechanism that underlies the success of fractional calculus ​compared with standard mathematics for describing stochastic processes by ​proposing a Fibonacci approach, where we assume that the complex processes evolves cumulatively in fractal space and discrete time. ​Thus, when the differential-integral order α is attained, this indicates the ​involvement of the viscosity of the medium ​in the evolving process. The future value of the diminishing physical quantity is obtained in terms of the Mittag-Leffler function (MLF) and two rheological laws ​are inferred from the asymptotic limits. Thus, we conclude that the differential-integral calculus of fractional mathematics implicitly embodies the cumulative diminution mechanism ​that occurs in a viscous medium.

  18. The impact of cumulative family risks on various levels of food insecurity.

    Science.gov (United States)

    Hernandez, Daphne C

    2015-03-01

    The study uses the Fragile Families and Child Well-being Study (N=2025) to examine the relationship between four cumulative family risk indices and refined measures of food hardship: marginal food security, low food security, and very low food security. Regression analyses indicate that cumulative family risk indices are useful in differentiating various levels of food insecurity. Specifically, the maternal poor health and risky health behaviors index is pertinent for distinguishing (1) food insecure from marginal food secure households and (2) very low food secure from low food secure households. In addition, the financial strain index is pertinent for differentiating between marginal food secure families from food secure families among non-poor households. Connecting food assistance programs with established social services may decrease the negative impact that cumulative family-level risk factors have on families' varying levels of food insecurity.

  19. Quasi-gaussian fixed points and factorial cumulants in nuclear multifragmentation

    CERN Document Server

    Lacroix, D

    1996-01-01

    We re-analyze the conditions for the phenomenon of intermittency (self-similar fluctuations) to occur in models of multifragmentation. Analyzing two different mechanisms, the bond-percolation and the ERW (Elattari, Richert and Wagner) statistical fragmentation models, we point out a common quasi-gaussian shape of the total multiplicity distribution in the critical range. The fixed-point property is also observed for the multiplicity of the second bin. Fluctuations are studied using scaled factorial cumulants instead of scaled factorial moments. The second-order cumulant displays the intermittency signal while higher order cumulants are equal to zero, revealing a large information redundancy in scaled factorial moments. A practical criterion is proposed to identify the gaussian feature of light-fragment production, distinguishing between a self-similarity mechanism (ERW) and the superposition of independent sources (percolation).

  20. Cumulative risk assessment of phthalate exposure of Danish children and adolescents using the hazard index approach

    DEFF Research Database (Denmark)

    Søeborg, T; Frederiksen, H; Andersson, Anna-Maria

    2012-01-01

    and adolescents and resulting estimated daily intakes of four different phthalates. These daily intake estimates are used for a cumulative risk assessment with anti-androgenic effects as the endpoint using Tolerable Daily Intake (TDI) values determined by the European Food Safety Authorities (EFSA) or Reference...... endpoint for the phthalates included in this article. Using the EFSA TDI values, 12 children exceeded the hazard quotient for the sum of di-n-butyl phthalate and di-iso-butyl phthalate (∑DBP((i+n)) ) and one child exceeded the hazard quotient for di-(2-ethylhexyl)phthalate (DEHP). Nineteen children...... exceeded the cumulated hazard index for three phthalates. Using the RfD AA values, one child exceeded the hazard quotient for DEHP and the same child exceeded the cumulated hazard index for four phthalates. The EFSA TDI approach thus is more restrictive and identifies ∑DBP((i+n)) as the compound...

  1. Robust user equilibrium model based on cumulative prospect theory under distribution-free travel time

    Institute of Scientific and Technical Information of China (English)

    王伟; 孙会君; 吴建军

    2015-01-01

    The assumption widely used in the user equilibrium model for stochastic network was that the probability distributions of the travel time were known explicitly by travelers. However, this distribution may be unavailable in reality. By relaxing the restrictive assumption, a robust user equilibrium model based on cumulative prospect theory under distribution-free travel time was presented. In the absence of the cumulative distribution function of the travel time, the exact cumulative prospect value (CPV) for each route cannot be obtained. However, the upper and lower bounds on the CPV can be calculated by probability inequalities. Travelers were assumed to choose the routes with the best worst-case CPVs. The proposed model was formulated as a variational inequality problem and solved via a heuristic solution algorithm. A numerical example was also provided to illustrate the application of the proposed model and the efficiency of the solution algorithm.

  2. Adaptive gamma correction based on cumulative histogram for enhancing near-infrared images

    Science.gov (United States)

    Huang, Zhenghua; Zhang, Tianxu; Li, Qian; Fang, Hao

    2016-11-01

    Histogram-based methods have been proven their ability in image enhancement. To improve low contrast while preserving details and high brightness in near-infrared images, a novel method called adaptive gamma correction based on cumulative histogram (AGCCH) is studied in this paper. This novel image enhancement method improves the contrast of local pixels through adaptive gamma correction (AGC), which is formed by incorporating a cumulative histogram or cumulative sub-histogram into the weighting distribution. Both qualitatively and quantitatively, experimental results demonstrate that the proposed image enhancement with the AGCCH method can perform well in brightness preservation, contrast enhancement, and detail preservation, and it is superior to previous state-of-the-art methods.

  3. Cumulative risk assessment of the intake of organophosphorus and carbamate pesticides in the Danish diet

    DEFF Research Database (Denmark)

    Jensen, A. F.; Petersen, Annette; Granby, Kit

    2003-01-01

    The aim of the study is to evaluate the potential cumulative effects of organophosphorus and carbamate pesticides that act through a common mechanism of toxicity, and to assess the long- and short-term risks for the Danish population. The intake estimates are based on dietary intake data collected...... in the Danish nation-wide food consumption survey in 1995. The pesticide data are based on the Danish pesticide residue-monitoring programme from 1996-2001. The amount of 35 organophosphorus pesticides and carbamates were included in the cumulative risk assessment. Processing factors, such as reduction...... of pesticide levels by rinsing and peeling, were applied in the exposure assessment. The "Toxicity Equivalence Factor" (TEF) approach was used to normalise the toxicity of the different organophosphorus and carbamate pesticides. Cumulative chronic exposure of organophosphorus and carbamates pesticides via...

  4. Effects of multiple context and cumulative stress on urban children's adjustment in elementary school.

    Science.gov (United States)

    Morales, Julie R; Guerra, Nancy G

    2006-01-01

    Using longitudinal data collected over 2 years on a sample of 2,745 urban elementary school children (1st-6th graders, ages 6-11 years) from economically disadvantaged communities, effects of stressful experiences within 3 contexts (school, family, neighborhood), cumulative stress, and multiple context stress on 3 indices of children's adjustment (achievement, depression, and aggression) were examined. All 3 stressor contexts were related contemporaneously and longitudinally to negative outcomes across adjustment measures, with differential paths in each predictive model. Cumulative stress was linearly related to increases in adjustment problems but multiple context stress was not related to problematic adjustment beyond effects of cumulative stress alone. The important influence of life events stress on children's adjustment in disadvantaged communities is discussed.

  5. Kindling fires: examining the potential for cumulative learning in a Journalism curriculum

    KAUST Repository

    Kilpert, Leigh

    2013-01-01

    This study investigated context-dependency of learning as an indicator for students\\' potential to continue learning after graduation. We used Maton\\'s theoretical concepts of \\'cumulative\\' and \\'segmented\\' learning, and \\'semantic gravity\\', to look for context-independent learning in students\\' assessments in a Journalism curriculum. We postulated whether the curriculum constrained or enabled cumulative learning. Students\\' responses to assessments were coded by their degree of context-dependency, or semantic gravity. We found that, firstly, students are overly successful in producing context-dependent answers but struggle to deliver context-independent responses. Secondly, students were not effective when they used higher level knowledge principles without the foundation of lower level ones. Lastly, the marking criteria were encouraging markers to reward context-dependent answers over context-independent ones. This study has implications for educators interested in curriculum design that enables cumulative learning in discipline specific contexts. © 2013 Copyright Taylor and Francis Group, LLC.

  6. Intravenous Iron Therapy in Patients with Iron Deficiency Anemia: Dosing Considerations

    Science.gov (United States)

    Koch, Todd A.; Myers, Jennifer; Goodnough, Lawrence Tim

    2015-01-01

    Objective. To provide clinicians with evidence-based guidance for iron therapy dosing in patients with iron deficiency anemia (IDA), we conducted a study examining the benefits of a higher cumulative dose of intravenous (IV) iron than what is typically administered. Methods. We first individually analyzed 5 clinical studies, averaging the total iron deficit across all patients utilizing a modified Ganzoni formula; we then similarly analyzed 2 larger clinical studies. For the second of the larger studies (Study 7), we also compared the efficacy and retreatment requirements of a cumulative dose of 1500 mg ferric carboxymaltose (FCM) to 1000 mg iron sucrose (IS). Results. The average iron deficit was calculated to be 1531 mg for patients in Studies 1–5 and 1392 mg for patients in Studies 6-7. The percentage of patients who were retreated with IV iron between Days 56 and 90 was significantly (p < 0.001) lower (5.6%) in the 1500 mg group, compared to the 1000 mg group (11.1%). Conclusions. Our data suggests that a total cumulative dose of 1000 mg of IV iron may be insufficient for iron repletion in a majority of patients with IDA and a dose of 1500 mg is closer to the actual iron deficit in these patients. PMID:26257955

  7. Efficacy of a single high dose versus multiple low doses of LLLT on wounded skin fibroblasts

    Science.gov (United States)

    Hawkins, Denise H.; Abrahamse, Heidi

    2007-07-01

    Background/purpose: In vivo studies have demonstrated that phototherapy accelerates wound healing in the clinical environment; however the exact mechanism is still not completely understood. The main focus of this study was to use in vitro laboratory results to establish an effective treatment regimen that may be practical and applicable to the clinical environment. This in vitro study aimed to compare the cellular responses of wounded fibroblasts following a single exposure of 5 J/cm2 or multiple exposures of low doses (2.5 J/cm2 or 5 J/cm2) on one day of the week to a single application of a higher dose (16 J/cm2) on day 1 and day 4. Methodology: Cellular responses to Helium-Neon (632.8 nm) laser irradiation were evaluated by measuring changes in cell morphology, cell viability, cell proliferation, membrane integrity and DNA damage. Results: Wounded cells exposed to 5 J/cm2 on day 1 and day 4 showed an increase in cell viability, increase in the release of bFGF, increase in cell density, decrease in ALP enzyme activity and decrease in caspase 3/7 activity indicating a stimulatory effect. Wounded cells exposed to three doses of 5 J/cm2 on day 1 showed a decrease in cell viability and cell proliferation and an increase in LDH cytotoxicity and DNA damage indicating an inhibitory effect. Conclusion: Results indicate that cellular responses are influenced by the combination of dose administered, number of exposures and time between exposures. Single doses administered with sufficient time between exposures is more beneficial to restoring cell function than multiple doses within a short period. Although this work confirms previous reports on the cumulative effect of laser irradiation it provides essential information for the initiation of in vivo clinical studies.

  8. Cumulative asbestos exposure for US automobile mechanics involved in brake repair (circa 1950s-2000).

    Science.gov (United States)

    Finley, Brent L; Richter, Richard O; Mowat, Fionna S; Mlynarek, Steve; Paustenbach, Dennis J; Warmerdam, John M; Sheehan, Patrick J

    2007-11-01

    We analyzed cumulative lifetime exposure to chrysotile asbestos experienced by brake mechanics in the US during the period 1950-2000. Using Monte Carlo methods, cumulative exposures were calculated using the distribution of 8-h time-weighted average exposure concentrations for brake mechanics and the distribution of job tenure data for automobile mechanics. The median estimated cumulative exposures for these mechanics, as predicted by three probabilistic models, ranged from 0.16 to 0.41 fibers per cubic centimeter (f/cm(3)) year for facilities with no dust-control procedures (1970s), and from 0.010 to 0.012 f/cm(3) year for those employing engineering controls (1980s). Upper-bound (95%) estimates for the 1970s and 1980s were 1.96 to 2.79 and 0.07-0.10 f/cm(3) year, respectively. These estimates for US brake mechanics are consistent with, but generally slightly lower than, those reported for European mechanics. The values are all substantially lower than the cumulative exposure of 4.5 f/cm(3) year associated with occupational exposure to 0.1 f/cm(3) of asbestos for 45 years that is currently permitted under the current occupational exposure limits in the US. Cumulative exposures were usually about 100- to 1,000-fold less than those of other occupational groups with asbestos exposure for similar time periods. The cumulative lifetime exposure estimates presented here, combined with the negative epidemiology data for brake mechanics, could be used to refine the risk assessments for chrysotile-exposed populations.

  9. Study of teflon pads as high doses dosemeters; Estudo de pastilhas de teflon como dosimetros de doses altas

    Energy Technology Data Exchange (ETDEWEB)

    Teixeira, Maria Ines; Caldas, Linda V.E., E-mail: miteixeira@ipen.br, E-mail: lcaldas@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2013-11-01

    The aim of this work is to study the Teflon, which is used as a binder in the manufacture of dosimetric tablets, for the feasibility of this material as high dose dosemeter. In this paper we used the technique of thermally stimulated luminescence (OSL) to characterize the dosimetric properties of Teflon. Teflon samples were exposed to different doses of radiation, using a source of gamma radiation ({sup 60}Co). It was obtained dose-response curve between 100 Gy to 50 kGy and reproducibility of OSL response. The preliminary results show that Teflon is a useful material to high dose dosimetry.

  10. Neutron absorbed dose in a pacemaker CMOS

    Energy Technology Data Exchange (ETDEWEB)

    Borja H, C. G.; Guzman G, K. A.; Valero L, C.; Banuelos F, A.; Hernandez D, V. M.; Vega C, H. R. [Universidad Autonoma de Zacatecas, Unidad Academica de Estudios Nucleares, Cipres No. 10, Fracc. La Penuela, 98068 Zacatecas (Mexico); Paredes G, L., E-mail: fermineutron@yahoo.com [ININ, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico)

    2012-06-15

    The neutron spectrum and the absorbed dose in a Complementary Metal Oxide Semiconductor (CMOS), has been estimated using Monte Carlo methods. Eventually a person with a pacemaker becomes an oncology patient that must be treated in a linear accelerator. Pacemaker has integrated circuits as CMOS that are sensitive to intense and pulsed radiation fields. Above 7 MV therapeutic beam is contaminated with photoneutrons that could damage the CMOS. Here, the neutron spectrum and the absorbed dose in a CMOS cell was calculated, also the spectra were calculated in two point-like detectors in the room. Neutron spectrum in the CMOS cell shows a small peak between 0.1 to 1 MeV and a larger peak in the thermal region, joined by epithermal neutrons, same features were observed in the point-like detectors. The absorbed dose in the CMOS was 1.522 x 10{sup -17} Gy per neutron emitted by the source. (Author)

  11. The Bubbles of China Stock Market Based on Return Decomposition and Cumulative Return

    Institute of Scientific and Technical Information of China (English)

    ZHANG Xiao-xia; WU Chong-feng

    2006-01-01

    Using Capital Asset Pricing Model Integrating both Firm and Market (CAPMIFM), we first decompose the asset return into two components. One is called the fundamental return,which is related to the intrinsic value of the asset. The other is called bubble return, which is derived from the asset bubbles. Then a stock bubble return model bused on cumulative return is proposed. The model exhibits characterizing log-periodic oscillations and a power law acceleration of the cumulative return. Empirical results suggest that the model has a good fit for the bubbles of China stock market.

  12. Cumulative risk and asthma outcomes in inner-city African-American youth.

    Science.gov (United States)

    Josie, Katherine Leigh; Greenley, Rachel Neff; Drotar, Dennis

    2007-09-01

    A cumulative risk framework was used to examine the impact of the presence of multiple risk factors on key asthma outcomes (i.e., health-related quality of life [HRQoL], severity) for a sample of 149 inner-city African-American youth with asthma. The presence of a greater number of risk factors was associated with lower HRQoL and greater severity, regardless of age or gender. Cumulative risk methodology, in combination with selection of risk factors based on theoretical and empirical work, is a viable option for researchers and clinicians who are interested in examining the impact of multiple risk factors on disease functioning and status.

  13. General solution of cumulative second harmonic by Lamb wave propagation in a solid plate

    Institute of Scientific and Technical Information of China (English)

    Deng Mingxi

    2008-01-01

    A straightforward approach has been developed for the general solution of cumulative second harmonic by Lamb wave propagation in a solid plate. The present analyses of second-harmonic generation by Lamb waves focus on the cases where the phase velocity of the fundamental Lamb wave is exactly or approximately equal to that of the double frequency Lamb wave (DFLW). Based on the general solution obtained, the numerical analyses show that the cumulative second-harmonic fields are associated with the position of excitation source and the difference between the phase velocity of the fundamental Lamb wave and that of the dominant DFLW component.

  14. [Recommendations for the analysis of cumulated data in antimicrobial susceptibility in health institutions].

    Science.gov (United States)

    2010-04-01

    Due to the great variability in antimicrobial resistance patterns, local reports of cumulative antimicrobial susceptibility data are necessary in every health center. The purpose is to guide clinical decisions and the early detection of patterns that allow preventive measures to avoid dissemination of resistant strains. The main objective of this guide is to provide recommendations for the analysis of antimicrobial susceptibility data and elaboration of a local report. Recommendations provided in this guide are based on the Clinical and Laboratory Standards Institute (CLSI) document "Analysis and Presentation of Cumulative Antimicrobial Susceptibility Test Data" (3). Key aspects related to information gathering and data processing, analysis and presentation are described.

  15. Prediction of postoperative morbidity, mortality and rehabilitation in hip fracture patients: the cumulated ambulation score

    DEFF Research Database (Denmark)

    Foss, Nicolai Bang; Kristensen, Morten Tange; Kehlet, Henrik

    2006-01-01

    fracture patients with an independent walking function admitted from their own home. Rehabilitation followed a well-defined multimodal rehabilitation regimen and discharge criteria. MAIN OUTCOME MEASURE: Admission tests with a new mobility score to assess prefracture functional mobility and a short mental...... score for cognitive dysfunction were performed. On the first three postoperative days patients were assessed with the cumulated ambulation score consisting of a cumulated assessment of simple ambulation characteristics with a score from 0 to 18 (fully mobile). The three assessments were correlated...

  16. Universal Off-Equilibrium Scaling of Critical Cumulants in the QCD Phase Diagram

    Science.gov (United States)

    Mukherjee, Swagato; Venugopalan, Raju; Yin, Yi

    2016-11-01

    Exploiting the universality between the QCD critical point and the three-dimensional Ising model, closed form expressions derived for nonequilibrium critical cumulants on the crossover side of the critical point reveal that they can differ in both magnitude and sign from equilibrium expectations. We demonstrate here that key elements of the Kibble-Zurek framework of nonequilibrium phase transitions can be employed to describe the dynamics of these critical cumulants. Our results suggest that observables sensitive to critical dynamics in heavy-ion collisions should be expressible as universal scaling functions, thereby providing powerful model-independent guidance in searches for the QCD critical point.

  17. An Assessment of Cumulative Axial and Torsional Fatigue in a Cobalt-Base Superalloy

    Science.gov (United States)

    Kalluri, Sreeramesh; Bonacuse, Peter J.

    2010-01-01

    Cumulative fatigue under axial and torsional loading conditions can include both load-order (higMow and low/high) as well as load-type sequence (axial/torsional and torsional/axial) effects. Previously reported experimental studies on a cobalt-base superalloy, Haynes 188 at 538 C, addressed these effects. These studies characterized the cumulative axial and torsional fatigue behavior under high amplitude followed by low amplitude (Kalluri, S. and Bonacuse, P. J., "Cumulative Axial and Torsional Fatigue: An Investigation of Load-Type Sequance Effects," in Multiaxial Fatigue and Deformation: Testing and Prediction, ASTM STP 1387, S. Kalluri, and P. J. Bonacuse, Eds., American Society for Testing and Materials, West Conshohocken, PA, 2000, pp. 281-301) and low amplitude followed by high amplitude (Bonacuse, P. and Kalluri, S. "Sequenced Axial and Torsional Cumulative Fatigue: Low Amplitude Followed by High Amplitude Loading," Biaxial/Multiaxial Fatigue and Fracture, ESIS Publication 31, A. Carpinteri, M. De Freitas, and A. Spagnoli, Eds., Elsevier, New York, 2003, pp. 165-182) conditions. In both studies, experiments with the following four load-type sequences were performed: (a) axial/axial, (b) torsional/torsional, (c) axial/torsional, and (d) torsional/axial. In this paper, the cumulative axial and torsional fatigue data generated in the two previous studies are combined to generate a comprehensive cumulative fatigue database on both the load-order and load-type sequence effects. This comprehensive database is used to examine applicability of the Palmgren-langer-Miner linear damage rule and a nonlinear damage curve approach for Haynes 188 subjected to the load-order and load-type sequencing described above. Summations of life fractions from the experiments are compared to the predictions from both the linear and nonlinear cumulative fatigue damage approaches. The significance of load-order versus load-type sequence effects for axial and torsional loading conditions

  18. Childhood poverty and young adults' allostatic load: the mediating role of childhood cumulative risk exposure.

    Science.gov (United States)

    Evans, Gary W; Kim, Pilyoung

    2012-09-01

    Childhood poverty is linked to a host of physical and psychological disorders during childhood and later in life. In the study reported here, we showed that the proportion of childhood spent in poverty from birth to age 9 was linked to elevated allostatic load, a marker of chronic physiological stress, in 17-year-olds. Furthermore, this prospective longitudinal relationship was mediated by cumulative risk exposure at age 13. The greater the duration of early life spent in poverty, the greater the exposure to cumulative risk. This, in turn, leads to elevated allostatic load. Multiple psychological, biological, and neurological pathways likely account for the social patterning of psychological and physical disease.

  19. Thermal Hardware for the Thermal Analyst

    Science.gov (United States)

    Steinfeld, David

    2015-01-01

    The presentation will be given at the 26th Annual Thermal Fluids Analysis Workshop (TFAWS 2015) hosted by the Goddard Space Flight Center (GSFC) Thermal Engineering Branch (Code 545). NCTS 21070-1. Most Thermal analysts do not have a good background into the hardware which thermally controls the spacecraft they design. SINDA and Thermal Desktop models are nice, but knowing how this applies to the actual thermal hardware (heaters, thermostats, thermistors, MLI blanketing, optical coatings, etc...) is just as important. The course will delve into the thermal hardware and their application techniques on actual spacecraft. Knowledge of how thermal hardware is used and applied will make a thermal analyst a better engineer.

  20. The correlation between elongation at break and thermal decomposition of aged EPDM cable polymer

    Science.gov (United States)

    Šarac, T.; Devaux, J.; Quiévy, N.; Gusarov, A.; Konstantinović, M. J.

    2017-03-01

    The effect of simultaneous thermal and gamma irradiation ageing on the mechanical and physicochemical properties of industrial EPDM was investigated. Accelerated ageing, covering a wide range of dose rates, doses and temperatures, was preformed in stagnant air on EPDM polymer samples extracted from the cables in use in the Belgian nuclear power plants. The mechanical properties, ultimate tensile stress and elongation at break, are found to exhibit the strong dependence on the dose, ageing temperature and dose rate. The thermal decomposition of aged polymer is observed to be the dose dependent when thermogravimetry test is performed under air atmosphere. No dose dependence is observed when thermal decomposition is performed under nitrogen atmosphere. The thermal decomposition rates are found to fully mimic the reduction of elongation at break for all dose rates and ageing temperatures. This effect is argued to be the result of thermal and radiation mediated oxidation degradation process.

  1. Establishment of a radiological dose assessment system for HANARO emergency preparedness

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Eun Han; Han, Moon Hee; Suh, Kyung Suk; Hwang, Won Tae; Choi, Young Gil

    1999-12-01

    A radiological dose assessment system has been established to calculate the three-dimensional wind field based on the observed data at meteorological towers, and to calculate the exposure dose in the radiological accidents or for emergency training. The wind fields program has been constructed to calculate the real-time wind field using the atmospheric stability and the diffusion parameters based on the meteorological data sets measured from two meteorological towers. The result is separated into the effective dose and thyroid dose with 4 age groups such as infant, children, teenage and adult. Dose rate and cumulated dose for above each termare calculated and repeated for the prediction and modification according to the elapsed time. The evaluated data sets are displayed on the map around KAERI site with social and environmental information which is made with GIS. (author)

  2. Cumulative approaches to track formation under swift heavy ion (SHI) irradiation: Phenomenological correlation with formation energies of Frenkel pairs

    Science.gov (United States)

    Crespillo, M. L.; Agulló-López, F.; Zucchiatti, A.

    2017-03-01

    An extensive survey for the formation energies of Frenkel pairs, as representative candidates for radiation-induced point defects, is presented and discussed in relation to the cumulative mechanisms (CM) of track formation in dielectric materials under swift heavy ion (SHI) irradiation. These mechanisms rely on the generation and accumulation of point defects during irradiation followed by collapse of the lattice once a threshold defect concentration is reached. The physical basis of those approaches has been discussed by Fecht as a defect-assisted transition to an amorphous phase. Although a first quantitative analysis of the CM model was previously performed for LiNbO3 crystals, we have, here, adopted a broader phenomenological approach. It explores the correlation between track formation thresholds and the energies for Frenkel pair formation for a broad range of materials. It is concluded that the threshold stopping powers can be roughly scaled with the energies required to generate a critical Frenkel pair concentration in the order of a few percent of the total atomic content. Finally, a comparison with the predictions of the thermal spike model is discussed within the analytical Szenes approximation.

  3. Merging Thermal Plumes in the Indoor Environment

    DEFF Research Database (Denmark)

    Bjørn, Erik; Nielsen, Peter V.

    This experimental work deals with the basic problem of merging thermal plumes from heat sources situated in the vicinity of each other. No studies have been made yet of how close two heat sources must be to each other, before they can be considered as a single source with a cumulative heat effect......, and how far apart they must be to be considered separate. Also, it is not known how the flow field behaves in the intermediate fase, where the plumes are neither completely joined nor completely separate. A possible, very simple, solution of the velocity distribution between two plumes is to assume...

  4. Use of the cytosensor microphysiometer to predict results of a 21-day cumulative irritation patch test in humans.

    Science.gov (United States)

    Landin, Wendell E; Mun, Greg C; Nims, Raymond W; Harbell, John W

    2007-09-01

    The cytosensor microphysiometer (mu phi) was investigated as a rapid, relatively inexpensive test to predict performance of skin cleansing wipes on the human 21-day cumulative irritation patch test (21CIPT). It indirectly measures metabolic rate changes in L929 cells as a function of test article dose, by measuring the acidification rate in a low-buffer medium. The dose producing a 50% reduction in metabolic rate (MRD50), relative to the baseline rate, is used as a measure of toxicity. The acute toxicity of the mu phi assay can be compared to the chronic toxicity of the 21CIPT, which is based largely on the exposure of test agents to the epidermal cells, resulting in damage and penetration of the stratum corneum leading to cell toxicity. Two series of surfactant-based cleansing wipe products were tested via the mu phi assay and 21CIPT. The first series, consisting of 20 products, was used to determine a prediction model. The second series of 38 products consisted of routine product development formulas or marketed products. Comparing the results from both tests, samples with an MRD50 greater than 50 mg/ml provided a 21CIPT score consistent with a product that performs satisfactorily in the market. When the MRD50 was greater than 78 mg/ml, the 21CIPT score was usually zero. The mu phi may be more sensitive than the 21CIPT for ranking minimally irritating materials. The mu phi assay is useful as a screen for predicting the performance of a wet wipes formula on the 21CIPT, and concurrently reduces the use of animals for safety testing in a product development program for cleansing wipes.

  5. The Association between Cumulative Psychosocial Risk and Cervical HPV Infection Among Female Adolescents in a Free Vaccination Program

    Science.gov (United States)

    Linares, Lourdes Oriana; Shankar, Viswanathan; Diaz, Angela; Nucci-Sack, Anne; Strickler, Howard D.; Peake, Ken; Weiss, Jocelyn; Burk, Robert D.; Schlecht, Nicolas F.

    2016-01-01

    Objective This study investigated the association of cervical Human Papillomavirus (HPV) infection with cumulative psychosocial risk reflecting family disadvantage, psychological distress, and unhealthy life style. Methods The sample (N=745) was comprised of sexually-active female adolescent patients (12-19 years), primarily ethnic minorities, enrolled in a free HPV vaccination program. Subjects completed questionnaires and provided cervical swabs for HPV DNA testing. Unweighted and weighted Principal Component Analyses (PCA) for categorical data were used to derive multi-systemic psychosocial risk indices using nine indicators: low socioeconomic status, lack of adult involvement, not attending high-school/college, history of treatment for depression/anxiety, antisocial/delinquent behavior, number of recent sexual partners, use of alcohol, use of drugs, and dependency risk for alcohol/drugs. The association between cervical HPV (any-type, high risk-types, vaccine-types) assayed by polymerase chain reaction and self-reported number of psychosocial risk indicators was estimated using multivariable logistic regression. Results Subjects had a median of three psychosocial risk indicators. Multiple logistic regression analyses showed associations with unweighted and weighted number of psychosocial indicators for HPV any-type (adjusted odds ratio [aOR]=1.1; 95% confidence interval [CI]: 1.0-1.2 ); with the strongest associations between weighted drug/alcohol use, drug/alcohol dependency risk, and antisocial/delinquent behavior and detection of HPV vaccine-types (aOR=1.5; 95%CI: 1.1-2.0) independent of number of recent sexual partners and vaccine dose (0-3). Conclusion Increased HPV infections including HPV vaccine-types were associated with greater number of psychosocial risk indicators even after controlling for demographics, sexual behavior, history of chlamydia, and vaccine dose. PMID:25985216

  6. Thermal neutron dosimetry using electrochemical etching

    Energy Technology Data Exchange (ETDEWEB)

    Su, S.J.; Sanders, M.E.; Morgan, K.Z.

    1979-07-10

    This study demonstrates the feasibility of using high LET particle radiators to determine the thermal neutron dose by reaction particle registration in low background polycarbonate foils using electrochemical etching. When used in conjunction with the already proven fast neutron recoil particle track registration technique, a viable fast and thermal neutron dosimeter is realized with the advantages of being: non-fading, insensitive to low LET radiation reactions, inexpensive in both processing and materials, useable over a wide dose range, a permanant record and good reproducibility, highly sensitive, and tissue equivalent and a dose equivalent response over a wide range. Most importantly, it finally provides a simple and reliable dosimeter for both the fast and thermal neutron components.

  7. Ground-Truthing Validation to Assess the Effect of Facility Locational Error on Cumulative Impacts Screening Tools

    OpenAIRE

    Sadd, J. L.; Hall, E. S.; Pastor, M.; Morello-Frosch, R. A.; D. Lowe-Liang; Hayes, J.; Swanson, C

    2015-01-01

    Researchers and government regulators have developed numerous tools to screen areas and populations for cumulative impacts and vulnerability to environmental hazards and risk. These tools all rely on secondary data maintained by government agencies as part of the regulatory and permitting process. Stakeholders interested in cumulative impacts screening results have consistently questioned the accuracy and completeness of some of these datasets. In this study, three cumulative impacts screenin...

  8. Thermal Clothing

    Science.gov (United States)

    1997-01-01

    Gateway Technologies, Inc. is marketing and developing textile insulation technology originally developed by Triangle Research and Development Corporation. The enhanced thermal insulation stems from Small Business Innovation Research contracts from NASA's Johnson Space Center and the U.S. Air Force. The effectiveness of the insulation comes from the microencapsulated phase-change materials originally made to keep astronauts gloved hands warm. The applications for the product range from outer wear, housing insulation, and blankets to protective firefighting gear and scuba diving suits. Gateway has developed and begun marketing thermal regulating products under the trademark, OUTLAST. Products made from OUTLAST are already on the market, including boot and shoe liners, winter headgear, hats and caps for hunting and other outdoor sports, and a variety of men's and women's ski gloves.

  9. Production of high-PT cumulative particles in proton-nuclear interactions at 50 GeV

    CERN Document Server

    Ammosov, V V; Viktorov, V A; Gapienko, V A; Gapienko, G S; Gres, V N; Korotkov, V A; Mysnik, A I; Prudkoglyad, A F; Sviridov, Yu M; Semak, A A; Terekhov, V I; Uglekov, V Ya; Ukhanov, M N; Chuiko, B V; Baldin, A A; Shimanskiy, S S

    2014-01-01

    The data on production of cumulative particles in the high transverse momenta domain (up to ~ 3.5 GeV/c) in proton-nuclear interactions are presented for the first time. An indication on the local character of particle production in the cumulative domain is obtained. The observed strong dependence of the particle production cross section on the atomic mass of the target does not fit the A - dependence obtained in the pre-cumulative and cumulative domains for low transverse momenta at constant part of the exponent. The experiment was performed at U70 (IHEP) with the extracted 50 GeV/c proton beam.

  10. Weak self-directed learning skills hamper performance in cumulative assessment

    NARCIS (Netherlands)

    Tio, Rene A.; Stegmann, Mariken E.; Koerts, Janke; van Os, Titus W. D. P.; Cohen-Schotanus, Janke

    2016-01-01

    Background: Self-regulated learning is an important determinant of academic performance. Previous research has shown that cumulative assessment encourages students to work harder and improve their results. However, not all students seem to respond as intended. We investigated the influence of studen

  11. Low Fruit/Vegetable Consumption in the Home: Cumulative Risk Factors in Early Childhood

    Science.gov (United States)

    Ward, Wendy L.; Swindle, Taren M.; Kyzer, Angela L.; Whiteside-Mansell, Leanne

    2015-01-01

    Cumulative risk theory suggests that a variety of social risk factors would have an additive effect on obesity risk. Multiple studies have suggested that obesity is related to basic resources such as transportation and financial resources. Additional research points to parental engagement and parental monitoring as additional sources of risk. This…

  12. Cross-cultural validation of the Italian version of the Cumulated Ambulation Score

    DEFF Research Database (Denmark)

    Grana, Elisa; Verzellotti, Simone; Grassi, Federico A;

    2016-01-01

    Hip fractures are common in elderly patients, and walking impairment is a frequent complication. The Cumulated Ambulation Score (CAS) is a validated functional scale used to monitor easily three basic mobility activities in patients with hip fracture. The aim of this study was to translate, cross...

  13. A new approach to the management of cumulative environmental impacts, the Alberta Oil Sands area

    Energy Technology Data Exchange (ETDEWEB)

    Weagle, K.V. [Cumulative Environmental Association, Wood Buffalo, AB (Canada)

    2002-06-01

    Resource development in the oil sand industry of Northeastern Alberta is enjoying a wave of renewed interest fuelled in part by changes made in the tax and royalty structure for oil sands developments in the province, the development of new technology and the price of oil. Announcements were made of investments totalling approximately 51 billion dollars in the oil sand industry over the next ten years in all deposits. The issue of cumulative environmental effects has been amplified accordingly. In June 2000, an association was formed, the Cumulative Environmental Management Association (CEMA), consisting of stakeholders and based on consensus, with a mandate to address 72 issues related to potential cumulative impacts in the expanded development of the Wood Buffalo Region. Five working groups were formed, as well as three standing committees. To mitigate the cumulative effects, the working groups and standing committees are working on management objectives, management systems and research recommendations. The regulatory bodies receive the recommendations, and the implementation process involves the issuance of permits and licenses. Research and monitoring activities play a vital role in the environmental management system and are part of other current environmental initiatives. Some of the initiatives are managed by the Wood Buffalo Environmental Association, Regional Aquatics Monitoring Program, and the Canadian Oil Sands Network for Research and Development. These organizations touch on topics including air quality monitoring, aquatics monitoring and environmental research. 1 fig.

  14. Cumulative irritancy in the guinea pig from low grade irritant vehicles and the angry skin syndrome

    DEFF Research Database (Denmark)

    Andersen, Klaus Ejner; Maibach, H I

    1980-01-01

    A 4-week open cumulative irritancy test in guinea pigs discriminated between two low grade irritant vehicles, nonionic base (anhydrous) and hydrophilic ointment. The procedure might be useful as a predictive test for low grade irritants. The angry skin syndrome was established in the guinea pigs...

  15. Gender disparities among the association between cumulative family-level stress & adolescent weight status.

    Science.gov (United States)

    Hernandez, Daphne C; Pressler, Emily

    2015-04-01

    To investigate precursors to gender-related obesity disparities by examining multiple family-level stress indices. Analyses was based on adolescents born between 1975 and 1991 to women from the 1979 National Longitudinal Study of Youth data set (N=4762). Three types of family-level stressors were captured from birth to age 15: family disruption and conflict, financial strain, and maternal risky health behaviors, along with a total cumulative risk index. Body mass index was constructed on reference criteria for children outlined by the Centers for Disease Control. Multivariate logistic regressions were conducted for the three types of family stressors and for the total cumulative index. The accumulation of family disruption and conflict and financial stress was positively related to female adolescents being overweight/obese. Childhood exposure to maternal risky health behaviors was positively associated with higher weight status for male adolescents. Total cumulative stress was related to overweight/obesity for females, but not males. Different family-level stress indices are associated with the weight status of female and male adolescents. Combining types of family-level stress into one cumulative index appears to mask these differences. Copyright © 2015 Elsevier Inc. All rights reserved.

  16. Cumulative Effects of Exposure to Violence on Posttraumatic Stress in Palestinian and Israeli Youth

    Science.gov (United States)

    Dubow, Eric F.; Boxer, Paul; Huesmann, L. Rowell; Landau, Simha; Dvir, Shira; Shikaki, Khalil; Ginges, Jeremy

    2012-01-01

    We examine cumulative and prospective effects of exposure to conflict and violence across four contexts (ethnic-political, community, family, school) on posttraumatic stress (PTS) symptoms in Palestinian and Israeli youth. Interviews were conducted with 600 Palestinian and 901 Israeli (Jewish and Arab) children (ages 8, 11, and 14) and their…

  17. ENVIRONMENTAL AUDITING: A Synoptic Approach for Assessing CumulativeImpacts to Wetlands

    Science.gov (United States)

    Abbruzzese; Leibowitz

    1997-05-01

    / The US Environmental Protection Agency's Wetlands ResearchProgram has developed the synoptic approach as a proposed method forassessing cumulative impacts to wetlands by providing both a general and acomprehensive view of the environment. It can also be applied more broadly toregional prioritization of environmental issues. The synoptic approach is aframework for making comparisons between landscape subunits, such aswatersheds, ecoregions, or counties, thereby allowing cumulative impacts tobe considered in management decisions. Because there is a lack of tools thatcan be used to address cumulative impacts within regulatory constraints, thesynoptic approach was designed as a method that could make use of availableinformation and best professional judgement. Thus, the approach is acompromise between the need for rigorous results and the need for timelyinformation. It is appropriate for decision making when quantitative,accurate information is not available; the cost of improving existinginformation or obtaining better information is high; the cost of a wronganswer is low; there is a high demand for the information; and the situationcalls for setting priorities between multiple decisions versus optimizing fora single decision. The synoptic approach should be useful for resourcemanagers because an assessment is timely; it can be completed within one totwo years at relatively low cost, tested, and improved over time. Anassessment can also be customized to specific needs, and the results arepresented in mapped format. However, the utility of a synoptic assessmentdepends on how well knowledge of the environment is incorporated into theassessment, relevant to particular management questions.KEY WORDS: Cumulative impact assessment; Landscape ecology; Regionalprioritization

  18. Measurement of polarization of cumulative protons in the reaction. gamma. A. -->. pX

    Energy Technology Data Exchange (ETDEWEB)

    Avakyan, R.A.; Avakyan, E.O.; Avetisyan, A.; Asatryan, R.A.; Gavalyan, V.G.; Garibyan, Y.A.; Danagulyan, S.S.; Eganov, V.S.; Keropyan, I.A.; Marukyan, G.O.

    1985-09-01

    Polarization of cumulative protons in the reaction ..gamma..A..-->..pX has been measured in the 190--270 MeV proton energy range for the nuclei C, Cu, Sn, and Pb. The measured polarization is practically independent of the mass number of the nucleus and of the proton energy.

  19. Polarization of cumulative protons in the reaction. gamma. A r arrow pX

    Energy Technology Data Exchange (ETDEWEB)

    Avakyan, R.O.; Avetisyan, A.E.; Arestakesyan, G.A.; Bartikyan, M.V.; Garibyan, Y.A.; Grigoryan, A.E.; Eganov, V.S.; Karapetyan, A.P.; Karapetyan, M.P.; Keropyan, I.A.; and others

    1989-02-01

    The polarization of cumulative protons has been measured in the reaction {gamma}{ital A}{r arrow}{ital pX} in the proton-energy region 170--270 MeV for C and Sn nuclei in bremsstrahlung beams produced by 4.5- and 1.5-GeV electrons. The measured polarization value is close to zero.

  20. Cumulative Risk and Teacher Well-Being in the Democratic Republic of the Congo

    Science.gov (United States)

    Wolf, Sharon; Torrente, Catalina; McCoy, Marissa; Rasheed, Damira; Aber, J. Lawrence

    2015-01-01

    Remarkably little systematic research has examined the living and working conditions for teachers in sub-Saharan Africa and how such conditions predict teacher well-being. This study assesses how various risks across several domains of teachers' lives--measured as a "cumulative risk index"--predict motivation, burnout, and job…

  1. New approaches to uncertainty analysis for use in aggregate and cumulative risk assessment of pesticides

    NARCIS (Netherlands)

    Kennedy, M.C.; Voet, van der H.; Roelofs, V.J.; Roelofs, W.; Glass, C.R.; Boer, de W.J.; Kruisselbrink, J.W.; Hart, A.D.M.

    2015-01-01

    Risk assessments for human exposures to plant protection products (PPPs) have traditionally focussed on single routes of exposure and single compounds. Extensions to estimate aggregate (multi-source) and cumulative (multi-compound) exposure from PPPs present many new challenges and additional uncert

  2. Probabilistic cumulative risk assessment of anti-androgenic pesticides in food

    DEFF Research Database (Denmark)

    Müller, Anne Kirstine; Nielsen, Elsa

    2008-01-01

    A cumulative risk assessment of three anti-androgenic pesticides vinclozolin, procymidone and prochloraz in combination has been carried out using an Integrated Probabilistic Risk Assessment (IPRA) model. In the model, variability in both exposure and sensitivity between individuals were combined...

  3. Interactive Contributions of Cumulative Peer Stress and Executive Function Deficits to Depression in Early Adolescence

    Science.gov (United States)

    Agoston, Anna M.; Rudolph, Karen D.

    2016-01-01

    Exposure to peer stress contributes to adolescent depression, yet not all youth experience these effects. Thus, it is important to identify individual differences that shape the consequences of peer stress. This research investigated the interactive contribution of cumulative peer stress during childhood (second-fifth grades) and executive…

  4. Cumulative Family Risk Predicts Increases in Adjustment Difficulties across Early Adolescence

    Science.gov (United States)

    Buehler, Cheryl; Gerard, Jean M.

    2013-01-01

    Family is an important socialization context for youth as they move through early adolescence. A significant feature of this complex socialization context is the accumulation of potential family risk factors that may compromise youth adjustment. This study examined cumulative family risk and adolescents' adjustment difficulties in 416 two-parent…

  5. On Interpreting and Extracting Information from the Cumulative Distribution Function Curve: A New Perspective with Applications

    Science.gov (United States)

    Balasooriya, Uditha; Li, Jackie; Low, Chan Kee

    2012-01-01

    For any density function (or probability function), there always corresponds a "cumulative distribution function" (cdf). It is a well-known mathematical fact that the cdf is more general than the density function, in the sense that for a given distribution the former may exist without the existence of the latter. Nevertheless, while the density…

  6. New use of global warming potentials to compare cumulative and short-lived climate pollutants

    Science.gov (United States)

    Allen, Myles R.; Fuglestvedt, Jan S.; Shine, Keith P.; Reisinger, Andy; Pierrehumbert, Raymond T.; Forster, Piers M.

    2016-08-01

    Parties to the United Nations Framework Convention on Climate Change (UNFCCC) have requested guidance on common greenhouse gas metrics in accounting for Nationally determined contributions (NDCs) to emission reductions. Metric choice can affect the relative emphasis placed on reductions of `cumulative climate pollutants' such as carbon dioxide versus `short-lived climate pollutants' (SLCPs), including methane and black carbon. Here we show that the widely used 100-year global warming potential (GWP100) effectively measures the relative impact of both cumulative pollutants and SLCPs on realized warming 20-40 years after the time of emission. If the overall goal of climate policy is to limit peak warming, GWP100 therefore overstates the importance of current SLCP emissions unless stringent and immediate reductions of all climate pollutants result in temperatures nearing their peak soon after mid-century, which may be necessary to limit warming to ``well below 2 °C'' (ref. ). The GWP100 can be used to approximately equate a one-off pulse emission of a cumulative pollutant and an indefinitely sustained change in the rate of emission of an SLCP. The climate implications of traditional CO2-equivalent targets are ambiguous unless contributions from cumulative pollutants and SLCPs are specified separately.

  7. Effects of Multiple Context and Cumulative Stress on Urban Children's Adjustment in Elementary School

    Science.gov (United States)

    Morales, Julie R.; Guerra, Nancy G.

    2006-01-01

    Using longitudinal data collected over 2 years on a sample of 2,745 urban elementary school children (1st-6th graders, ages 6-11 years) from economically disadvantaged communities, effects of stressful experiences within 3 contexts (school, family, neighborhood), cumulative stress, and multiple context stress on 3 indices of children's adjustment…

  8. Learning curve of vitrification assessed by cumulative summation test for learning curve (LC-CUSUM).

    Science.gov (United States)

    Dessolle, Lionel; Biau, David J; de Larouzière, Vanina; Ravel, Célia; Antoine, Jean-Marie; Daraï, Emile; Mandelbaum, Jacqueline

    2009-09-01

    We used the cumulative summation test for learning curve (LC-CUSUM), a specifically designed statistical tool, to evaluate the first 50 procedures performed by a trainee in vitrification and to provide a usable model for monitoring the learning process of this technique. Given the lack of models to evaluate IVF technologies, the CUSUM methodology could prove useful for quality control in laboratories.

  9. Interactive Contributions of Cumulative Peer Stress and Executive Function Deficits to Depression in Early Adolescence

    Science.gov (United States)

    Agoston, Anna M.; Rudolph, Karen D.

    2016-01-01

    Exposure to peer stress contributes to adolescent depression, yet not all youth experience these effects. Thus, it is important to identify individual differences that shape the consequences of peer stress. This research investigated the interactive contribution of cumulative peer stress during childhood (second-fifth grades) and executive…

  10. Cognitive requirements of cumulative culture: teaching is useful but not essential.

    Science.gov (United States)

    Zwirner, Elena; Thornton, Alex

    2015-11-26

    The cumulative nature of human culture is unique in the animal kingdom. Progressive improvements in tools and technologies have facilitated humanity's spread across the globe and shaped human evolution, but the cognitive mechanisms enabling cultural change remain unclear. Here we show that, contrary to theoretical predictions, cumulative improvements in tools are not dependent on specialised, high-fidelity social learning mechanisms. Participants were tasked with building a basket to carry as much rice as possible using a set of everyday materials and divided into treatment groups with differing opportunities to learn asocially, imitate, receive teaching or emulate by examining baskets made by previous chain members. Teaching chains produced more robust baskets, but neither teaching nor imitation were strictly necessary for cumulative improvements; emulation chains generated equivalent increases in efficacy despite exhibiting relatively low copying fidelity. People used social information strategically, choosing different materials to make their baskets if the previous basket in the chain performed poorly. Together, these results suggest that cumulative culture does not rest on high-fidelity social learning mechanisms alone. Instead, the roots of human cultural prowess may lie in the interplay of strategic social learning with other cognitive traits including the ability to reverse engineer artefacts through causal reasoning.

  11. Two year cumulative incidence of trunk abnormalities in a schoolpopulation in Rotterdam, the Netherlands

    NARCIS (Netherlands)

    A.A.J.M. Hazebroek-Kampschreur (Alice); A. Hofman (Albert); A. van Dijk (Ad); B. van Linge (Bert)

    1995-01-01

    textabstractWe conducted a study of the 2 year cumulative incidence of trunk abnormalities in a cohort of 3,071 11 year old children (1,621 boys, 1,450 girls). The following data were recorded: height, weight, signs of puberty and menarche. Trunk abnormality was assessed in the erect child

  12. Cumulative production of pions by heavy baryonic resonances in proton-nucleus collisions

    Science.gov (United States)

    Motornenko, A.; Gorenstein, M. I.

    2017-02-01

    Pion production in proton-nucleus (p+A) collisions outside the kinematical boundary of proton-nucleon (p+N) reactions and the so-called cumulative effect are studied. Restrictions from energy-momentum conservation of the energy of pions emitted in the backward direction in the target rest frame are analyzed. It is assumed that the cumulative pions are produced in p+A reactions by heavy baryonic resonances. The baryonic resonances are first created in p+N reactions. Due to successive collisions with nuclear nucleons, the masses of these resonances may then increase and, simultaneously, their longitudinal velocities decrease. We also use the ultra relativistic quantum molecular dynamics model to reveal the key role of successive collisions of baryonic resonances with nuclear nucleons for cumulative pion production in p+A reactions. Further experimental studies of cumulative hadron production in p+A reactions at high collision energies are needed to search for heavy hadron-like objects and investigate their properties.

  13. Kindling Fires: Examining the Potential for Cumulative Learning in a Journalism Curriculum

    Science.gov (United States)

    Kilpert, Leigh; Shay, Suellen

    2013-01-01

    This study investigated context-dependency of learning as an indicator for students' potential to continue learning after graduation. We used Maton's theoretical concepts of "cumulative" and "segmented" learning, and "semantic gravity", to look for context-independent learning in students' assessments…

  14. Evaluation of Cumulative Ecosystem Response to Restoration Projects in the Lower Columbia River and Estuary, 2010

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, Gary E.; Diefenderfer, Heida L.; Thom, Ronald M.; Roegner, G. Curtis; Ebberts, Blaine D.; Skalski, John R.; Borde, Amy B.; Dawley, Earl; Coleman, Andre M.; Woodruff, Dana L.; Breithaupt, Stephen A.; Cameron, April; Corbett, C.; Donley, Erin E.; Jay, D. A.; Ke, Yinghai; Leffler, K.; McNeil, C.; Studebaker, Cindy; Tagestad, Jerry D.

    2012-05-01

    This is the seventh and final annual report of a project (2004–2010) addressing evaluation of the cumulative effects of habitat restoration actions in the 235-km-long lower Columbia River and estuary. The project, called the Cumulative Effects (CE) study, was conducted for the U.S. Army Corps of Engineers Portland District by a collaboration of research agencies led by the Pacific Northwest National Laboratory. We achieved the primary goal of the CE study to develop a methodology to evaluate the cumulative effects of habitat actions in the Columbia Estuary Ecosystem Restoration Program. We delivered 1) standard monitoring protocols and methods to prioritize monitoring activities; 2) the theoretical and empirical basis for a CE methodology using levels-of-evidence; 3) evaluations of cumulative effects using ecological relationships, geo-referenced data, hydrodynamic modeling, and meta-analyses; and 4) an adaptive management process to coordinate and coalesce restoration efforts in the LCRE. A solid foundation has been laid for future comprehensive evaluations of progress made by the Columbia Estuary Ecosystem Restoration Program to understand, conserve, and restore ecosystems in the lower Columbia River and estuary.

  15. A validation of a posture matching approach for the determination of 3D cumulative back loads.

    Science.gov (United States)

    Sutherland, Chad A; Albert, Wayne J; Wrigley, Allan T; Callaghan, Jack P

    2008-03-01

    The purpose of this project was to investigate the amount of error in calculating cumulative lumbar spine kinetics using a posture matching approach (3DMatch) compared to a 3D coordinate electromagnetic tracking approach (FASTRAK). Six subjects were required to perform five repeats each of two symmetrical and two asymmetrical lifts while being simultaneously recorded from 4 camera views at viewing angles of 0 degrees , 45 degrees , 60 degrees and 90 degrees to the sagittal plane while wearing eight FASTRAK sensors to define an 8 segment rigid link model (RLM) of the head, arms, and trunk. Four hundred and eighty lifts (6 subjects x20 lifts x4 camera views) were analyzed using the 3DMatch posture-matching program to calculate the following cumulative loads at the L4/L5 joint: compression, anterior shear, posterior shear, reaction shear and extension moment. The errors in cumulative load calculation were determined as the difference between the values calculated for the same lifts using a 3D RLM that used electromagnetic motion tracking sensors (FASTRAK) positioned at the segment center of masses as model inputs. No significant difference (pposture matching by trained users can provide reasonable 3D data to calculate cumulative low back loads with a biomechanical model.

  16. Why cumulative impacts assessments of hydrocarbon activities in the Arctic fail to meet their purpose

    DEFF Research Database (Denmark)

    Kirkfeldt, Trine Skovgaard; Hansen, Anne Merrild; Olsen, Pernille;

    2016-01-01

    The Arctic Region is characterised by vulnerable ecosystems and residing indigenous people, dependent on nature for fishing and hunting. The Arctic also contains a wealth of non-living natural resources such as minerals and hydrocarbons. Synergies between increased access and growing global demand...... of methodology for assessment of cumulative impacts, knowledge gap of Arctic ecosystems and other....

  17. Cumulative Advantage in the Skill Development of STEM Graduate Students: A Mixed-Methods Study

    Science.gov (United States)

    Feldon, David F.; Maher, Michelle A.; Roksa, Josipa; Peugh, James

    2016-01-01

    Studies of skill development often describe a process of cumulative advantage, in which small differences in initial skill compound over time, leading to increasing skill gaps between those with an initial advantage and those without. We offer evidence of a similar phenomenon accounting for differential patterns of research skill development in…

  18. Cumulative Impact Assessment and Management : Guidance for the Private Sector in Emerging Markets

    OpenAIRE

    2013-01-01

    The major environmental and social management challenges that we face today, climate change, loss of biodiversity, the decline of ocean fisheries, limitations on food security, the scarcity of usable freshwater resources, displacement of communities with consequent increases in urban poverty, and inviability of traditional local livelihoods, are all the result of cumulative impacts from a ...

  19. A probabilistic analysis of cumulative carbon emissions and long-term planetary warming

    Science.gov (United States)

    Fyke, Jeremy; Damon Matthews, H.

    2015-11-01

    Efforts to mitigate and adapt to long-term climate change could benefit greatly from probabilistic estimates of cumulative carbon emissions due to fossil fuel burning and resulting CO2-induced planetary warming. Here we demonstrate the use of a reduced-form model to project these variables. We performed simulations using a large-ensemble framework with parametric uncertainty sampled to produce distributions of future cumulative emissions and consequent planetary warming. A hind-cast ensemble of simulations captured 1980-2012 historical CO2 emissions trends and an ensemble of future projection simulations generated a distribution of emission scenarios that qualitatively resembled the suite of Representative and Extended Concentration Pathways. The resulting cumulative carbon emission and temperature change distributions are characterized by 5-95th percentile ranges of 0.96-4.9 teratonnes C (Tt C) and 1.4 °C-8.5 °C, respectively, with 50th percentiles at 3.1 Tt C and 4.7 °C. Within the wide range of policy-related parameter combinations that produced these distributions, we found that low-emission simulations were characterized by both high carbon prices and low costs of non-fossil fuel energy sources, suggesting the importance of these two policy levers in particular for avoiding dangerous levels of climate warming. With this analysis we demonstrate a probabilistic approach to the challenge of identifying strategies for limiting cumulative carbon emissions and assessing likelihoods of surpassing dangerous temperature thresholds.

  20. Cumulative and Segmented Learning: Exploring the Role of Curriculum Structures in Knowledge-Building

    Science.gov (United States)

    Maton, Karl

    2009-01-01

    The present article extends Basil Bernstein's theorisation of "discourses" and "knowledge structures" to explore the potential of educational knowledge structures to enable or constrain cumulative learning, where students can transfer knowledge across contexts and build knowledge over time. It offers a means of overcoming…

  1. On the cumulants of increments for two classes of Brownian semi-stationary processes

    DEFF Research Database (Denmark)

    Urbina, José Ulises Márquez

    2015-01-01

    In this article we obtain formulae for the cumulants of the increments of two classes of Brownian semi-stationary (BSS) processes. The first class corresponds to BSS processes where the volatility is a Lévy semi-stationary process and the second class consists in BSS processes where the volatilit...

  2. The quantum normal form approach to reactive scattering : The cumulative reaction probability for collinear exchange reactions

    NARCIS (Netherlands)

    Goussev, Arseni; Schubert, Roman; Waalkens, Holger; Wiggins, Stephen

    2009-01-01

    The quantum normal form approach to quantum transition state theory is used to compute the cumulative reaction probability for collinear exchange reactions. It is shown that for heavy-atom systems such as the nitrogen-exchange reaction, the quantum normal form approach gives excellent results and

  3. Associations between parenting, media use, cumulative risk, and children’s executive functioning

    NARCIS (Netherlands)

    Linebarger, D.L.; Barr, R.; Lapierre, M.A.; Piotrowski, J.

    2014-01-01

    Objective: This study was designed to examine how parenting style, media exposure, and cumulative risk were associated with executive functioning (EF) during early childhood. Methods: A nationally representative group of US parents/caregivers (N = 1156) with 1 child between 2 and 8 years

  4. Effects of Cumulative Family Risk Factors on American Students' Academic Performance

    Science.gov (United States)

    Dunst, Carl J.; Hamby, Deborah W.

    2016-01-01

    The relationships between cumulative family risk factors and American students' academic performance were examined in all 50 States and the District of Columbia. Data from the 2007 "American Community Survey" were used to ascertain the percent of birth to 18 year old children in the United States who experienced three or more risk…

  5. Separate and Cumulative Effects of Adverse Childhood Experiences in Predicting Adult Health and Health Care Utilization

    Science.gov (United States)

    Chartier, Mariette J.; Walker, John R.; Naimark, Barbara

    2010-01-01

    Objectives: Objectives of this population-based study were: (1) to examine the relative contribution of childhood abuse and other adverse childhood experiences to poor adult health and increased health care utilization and (2) to examine the cumulative effects of adverse childhood experiences on adult health and health care utilization. Methods:…

  6. Cumulative violence exposure, emotional nonacceptance, and mental health symptoms in a community sample of women.

    Science.gov (United States)

    Sundermann, Jane M; Chu, Ann T; DePrince, Anne P

    2013-01-01

    Women exposed to more types of violence (e.g., emotional, physical, or sexual violence)--referred to here as cumulative violence exposure--are at risk for more severe mental health symptoms compared to women who are exposed to a single type of violence or no violence. Women exposed to violence may also experience greater emotional nonacceptance compared to women with no exposure to violence. Emotional nonacceptance refers to an unwillingness to experience emotional states, including cognitive and behavioral attempts to avoid experiences of emotion. Given the links between cumulative violence exposure, emotional nonacceptance, and mental health symptoms among female victims of violence, the current study tested victims' emotional nonacceptance as a partial mediator between cumulative violence exposure and the severity of 3 types of symptoms central to complex trauma responses: depression, dissociation, and posttraumatic stress disorder (PTSD) symptoms. A non-treatment-seeking community sample of women (N = 89; M age = 30.70 years) completed self-report questionnaires and interviews. Bootstrap procedures were then used to test 3 mediation models for the separate predictions of depression, dissociation, and PTSD symptoms. Results supported our hypotheses that emotional nonacceptance would mediate the relationship between women's cumulative violence exposure and severity for all symptom types. The current findings highlight the role that emotional nonacceptance may play in the development of mental health symptoms for chronically victimized women and point to the need for longitudinal research in such populations.

  7. Markov Chain Analysis of Cumulative Step-Size Adaptation on a Linear Constrained Problem.

    Science.gov (United States)

    Chotard, Alexandre; Auger, Anne; Hansen, Nikolaus

    2015-01-01

    This paper analyzes a (1, λ)-Evolution Strategy, a randomized comparison-based adaptive search algorithm optimizing a linear function with a linear constraint. The algorithm uses resampling to handle the constraint. Two cases are investigated: first, the case where the step-size is constant, and second, the case where the step-size is adapted using cumulative step-size adaptation. We exhibit for each case a Markov chain describing the behavior of the algorithm. Stability of the chain implies, by applying a law of large numbers, either convergence or divergence of the algorithm. Divergence is the desired behavior. In the constant step-size case, we show stability of the Markov chain and prove the divergence of the algorithm. In the cumulative step-size adaptation case, we prove stability of the Markov chain in the simplified case where the cumulation parameter equals 1, and discuss steps to obtain similar results for the full (default) algorithm where the cumulation parameter is smaller than 1. The stability of the Markov chain allows us to deduce geometric divergence or convergence, depending on the dimension, constraint angle, population size, and damping parameter, at a rate that we estimate. Our results complement previous studies where stability was assumed.

  8. Cumulative Adverse Financial Circumstances: Associations with Patient Health Status and Behaviors

    Science.gov (United States)

    Bisgaier, Joanna; Rhodes, Karin V.

    2011-01-01

    This article examines associations between cumulative adverse financial circumstances and patient health in a sample of 1,506 urban emergency department (ED) patients. Study participants completed a previously validated Social Health Survey between May and October 2009. Five categories of economic deprivation were studied: food insecurity, housing…

  9. Effect of cumulative strain on texture characteristics during wire drawing of eutectoid steels

    Energy Technology Data Exchange (ETDEWEB)

    Yang, F. [Jiangsu Key Laboratory of Advanced Metallic Materials, School of Materials Science and Engineering, Southeast University, NanJing, 211189 (China)], E-mail: yangfan.hit@gmail.com; Ma, C.; Jiang, J.Q. [Jiangsu Key Laboratory of Advanced Metallic Materials, School of Materials Science and Engineering, Southeast University, NanJing, 211189 (China); Feng, H.P.; Zhai, S.Y. [School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing 100083 (China)

    2008-10-15

    The texture characteristics associated with plastic deformation of Fe-C steels near-eutectoid composition during a continuous cold drawing process were thoroughly investigated by orientation distribution function analysis based on X-ray diffraction. The effect of cumulative drawing strains on the <1 1 0> fiber texture in drawn hypereutectoid and hypoeutectoid steel wires was discussed.

  10. 76 FR 82296 - Pyrethrins/Pyrethroid Cumulative Risk Assessment; Extension of Comment Period

    Science.gov (United States)

    2011-12-30

    ... AGENCY Pyrethrins/Pyrethroid Cumulative Risk Assessment; Extension of Comment Period AGENCY: Environmental Protection Agency (EPA). ACTION: Notice; extension of comment period. SUMMARY: EPA issued a notice... called ``the pyrethroids'') and opened a public comment period on this document and other supporting...

  11. Using Cumulative Sum Statistics to Detect Inconsistencies in Unproctored Internet Testing

    NARCIS (Netherlands)

    Tendeiro, Jorge N.; Meijer, Rob R.; Schakel, Lolle; Maij-de Meij, Annette M.

    2013-01-01

    Unproctored Internet Testing (UIT) is becoming more popular in personnel recruitment and selection. A drawback of UIT is that cheating is easy and, therefore, a proctored test is often administered after an UIT procedure. To detect inconsistent test scores from UIT, a cumulative sum procedure (CUSUM

  12. Two year cumulative incidence of trunk abnormalities in a schoolpopulation in Rotterdam, the Netherlands

    NARCIS (Netherlands)

    A.A.J.M. Hazebroek-Kampschreur (Alice); A. Hofman (Albert); A. van Dijk (Ad); B. van Linge (Bert)

    1995-01-01

    textabstractWe conducted a study of the 2 year cumulative incidence of trunk abnormalities in a cohort of 3,071 11 year old children (1,621 boys, 1,450 girls). The following data were recorded: height, weight, signs of puberty and menarche. Trunk abnormality was assessed in the erect child (asymmetr

  13. Cumulative versus end-of-course assessment : effects on self-study time and test performance

    NARCIS (Netherlands)

    Kerdijk, Wouter; Cohen-Schotanus, Janke; Mulder, B. Florentine; Muntinghe, Friso L. H.; Tio, Rene A.

    2015-01-01

    ContextStudents tend to postpone preparation for a test until the test is imminent, which raises various risks associated with cramming' behaviours, including that for suboptimal learning. Cumulative assessment utilises spaced testing to stimulate students to study more frequently and to prevent pro

  14. Nonsymbolic number and cumulative area representations contribute shared and unique variance to symbolic math competence.

    Science.gov (United States)

    Lourenco, Stella F; Bonny, Justin W; Fernandez, Edmund P; Rao, Sonia

    2012-11-13

    Humans and nonhuman animals share the capacity to estimate, without counting, the number of objects in a set by relying on an approximate number system (ANS). Only humans, however, learn the concepts and operations of symbolic mathematics. Despite vast differences between these two systems of quantification, neural and behavioral findings suggest functional connections. Another line of research suggests that the ANS is part of a larger, more general system of magnitude representation. Reports of cognitive interactions and common neural coding for number and other magnitudes such as spatial extent led us to ask whether, and how, nonnumerical magnitude interfaces with mathematical competence. On two magnitude comparison tasks, college students estimated (without counting or explicit calculation) which of two arrays was greater in number or cumulative area. They also completed a battery of standardized math tests. Individual differences in both number and cumulative area precision (measured by accuracy on the magnitude comparison tasks) correlated with interindividual variability in math competence, particularly advanced arithmetic and geometry, even after accounting for general aspects of intelligence. Moreover, analyses revealed that whereas number precision contributed unique variance to advanced arithmetic, cumulative area precision contributed unique variance to geometry. Taken together, these results provide evidence for shared and unique contributions of nonsymbolic number and cumulative area representations to formally taught mathematics. More broadly, they suggest that uniquely human branches of mathematics interface with an evolutionarily primitive general magnitude system, which includes partially overlapping representations of numerical and nonnumerical magnitude.

  15. Regional estimates of the transient climate response to cumulative CO2 emissions

    Science.gov (United States)

    Leduc, Martin; Matthews, H. Damon; de Elía, Ramón

    2016-05-01

    The Transient Climate Response to cumulative carbon Emissions (TCRE) measures the response of global temperatures to cumulative CO2 emissions. Although the TCRE is a global quantity, climate impacts manifest predominantly in response to local climate changes. Here we quantify the link between CO2 emissions and regional temperature change, showing that regional temperatures also respond approximately linearly to cumulative CO2 emissions. Using an ensemble of twelve Earth system models, we present a novel application of pattern scaling to define the regional pattern of temperature change per emission of CO2. Ensemble mean regional TCRE values range from less than 1 °C per TtC for some ocean regions, to more than 5 °C per TtC in the Arctic, with a pattern of higher values over land and at high northern latitudes. We find also that high-latitude ocean regions deviate more strongly from linearity as compared to land and lower-latitude oceans. This suggests that ice-albedo and ocean circulation feedbacks are important contributors to the overall negative deviation from linearity of the global temperature response to high levels of cumulative emissions. The strong linearity of the regional climate response over most land regions provides a robust way to quantitatively link anthropogenic CO2 emissions to local-scale climate impacts.

  16. Separate and Cumulative Effects of Adverse Childhood Experiences in Predicting Adult Health and Health Care Utilization

    Science.gov (United States)

    Chartier, Mariette J.; Walker, John R.; Naimark, Barbara

    2010-01-01

    Objectives: Objectives of this population-based study were: (1) to examine the relative contribution of childhood abuse and other adverse childhood experiences to poor adult health and increased health care utilization and (2) to examine the cumulative effects of adverse childhood experiences on adult health and health care utilization. Methods:…

  17. Probabilistic cumulative risk assessment of anti-androgenic pesticides in food.

    NARCIS (Netherlands)

    Müller, A.K.; Bosgra, S.; Boon, P.E.; van der Voet, H.; Nielsen, E.; Ladefoged, O.

    2009-01-01

    In this paper, we present a cumulative risk assessment of three anti-androgenic pesticides (vinclozolin, procymidone and prochloraz) using the relative potency factor (RPF) approach and an integrated probabilistic risk assessment (IPRA) model. RPFs for each substance were estimated for three reprodu

  18. Probabilistic cumulative risk assessment of anti-androgenic pesticides in food

    NARCIS (Netherlands)

    Muller, A.K.; Bosgra, S.; Boon, P.E.; Voet, van der H.; Nielsen, E.; Ladefoged, O.

    2009-01-01

    In this paper, we present a cumulative risk assessment of three anti-androgenic pesticides (vinclozolin, procymidone and prochloraz) using the relative potency factor (RPF) approach and an integrated probabilistic risk assessment (IPRA) model. RPFs for each substance were estimated for three reprodu

  19. Identification and Quantification of Cumulative Factors that Increase Environmental Exposures and Impacts

    Science.gov (United States)

    Evaluating the combined adverse effects of multiple stressors upon human health is an imperative component of cumulative risk assessment (CRA)1. In addition to chemical stressors, other non-chemical factors are also considered. For examples, smoking will elevate the risks of havi...

  20. Cumulative family risk predicts increases in adjustment difficulties across early adolescence.

    Science.gov (United States)

    Buehler, Cheryl; Gerard, Jean M

    2013-06-01

    Family is an important socialization context for youth as they move through early adolescence. A significant feature of this complex socialization context is the accumulation of potential family risk factors that may compromise youth adjustment. This study examined cumulative family risk and adolescents' adjustment difficulties in 416 two-parent families using four waves of annual longitudinal data (51% female youth). Risk factors in four family domains were examined: socioeconomic, parents' psychological realm, marital, and parenting. Cumulative family risk experienced while in 6th grade was associated concurrently with daughters' higher internalizing problems and with increased internalizing problems during early adolescence. Cumulative family risk was associated concurrently with sons' higher externalizing problems and with daughters' increased externalizing problems over time. Cumulative family risk was associated concurrently with lower grades and with declining grades over time for both daughters and sons. The number of risk domains also was associated with youths' adjustment difficulties during early adolescence, providing evidence that risk in two-parent families involves more than ineffective parenting. These findings suggest a critical need to provide strong support for families in reducing a variety of stressors across multiple family domains as their children traverse early adolescence.