UVER and UV index at high altitude in Northwestern Argentina.

PubMed

Utrillas, M P; Marín, M J; Esteve, A R; Salazar, G; Suarez, H; Castillo, J; Martínez-Lozano, J A

2016-10-01

Measurements of ultraviolet erythemal radiation (UVER) made during two years at three sites located at altitudes over 1000ma.s.l. in Northwestern Argentina (Salta, San Carlos, and El Rosal) have been used to estimate and analyze the UV Index (UVI) and the cumulative doses at these locations. For the UVER irradiance, data of January (maximum values) and June (minimum values) have been analyzed as representative of the year for all locations. The UVI reaches extreme (>11) values in >20% of the analyzed days in Salta (1190ma.s.l.), while these are reached in San Carlos (1611ma.s.l.) and El Rosal (3355ma.s.l.) in >40% of the analyzed days. Finally, the cumulative doses over an average year have also been studied for each location. The doses received during austral summer and autumn are of the same order, and represent one third of the annual dose, while the doses received during austral winter and spring represent one sixth of the annual dose approximately. Copyright © 2016 Elsevier B.V. All rights reserved.

A retrospective study on annual evaluation of radiation processing for frozen bone allografts complying to quality system requirements.

PubMed

Ramalingam, Saravana; Mohd, Suhaili; Samsuddin, Sharifah Mazni; Min, N G Wuey; Yusof, Norimah; Mansor, Azura

2015-12-01

Bone allografts have been used widely to fill up essential void in orthopaedic surgeries. The benefit of using allografts to replace and reconstruct musculoskeletal injuries, fractures or disease has obtained overwhelming acceptance from orthopaedic surgeons worldwide. However, bacterial infection and disease transmission through bone allograft transplantation have always been a significant issue. Sterilization by radiation is an effective method to eliminate unwanted microorganisms thus assist in preventing life threatening allograft associated infections. Femoral heads procured from living donors and long bones (femur and tibia) procured from cadaveric donors were sterilized at 25 kGy in compliance with international standard ISO 11137. According to quality requirements, all records of bone banking were evaluated annually. This retrospective study was carried out on annual evaluation of radiation records from 1998 until 2012. The minimum doses absorbed by the bones were ranging from 25.3 to 38.2 kGy while the absorbed maximum doses were from 25.4 to 42.3 kGy. All the bones supplied by our UMMC Bone Bank were sterile at the required minimum dose of 25 kGy. Our analysis on dose variation showed that the dose uniformity ratios in 37 irradiated boxes of 31 radiation batches were in the range of 1.003-1.251, which indicated the doses were well distributed.

External effective radiation dose to workers in the restricted area of the Fukushima Daiichi Nuclear Power Plant during the third year after the Great East Japan Earthquake.

PubMed

Sakumi, Akira; Miyagawa, Ryu; Tamari, Yuki; Nawa, Kanabu; Sakura, Osamu; Nakagawa, Keiichi

2016-03-01

Since the Great East Japan Earthquake on 11 March 2011, Iitate Village has continued to be classified as a deliberate evacuation area, in which residents are estimated to receive an annual additional effective radiation dose of >20 mSv. Some companies still operate in Iitate Village, with a special permit from the Cabinet Office Team in Charge of Assisting the Lives of Disaster Victims. In this study, we measured the annual effective radiation dose to workers in Iitate Village from 15 January to 13 December 2013. The workers stayed in Iitate for 10 h and left the village for the remaining 14 h each working day. They worked for 5 days each week in Iitate Village, but stayed outside of the village for the remaining 2 days each week. We found that the effective radiation dose of 70% of the workers was <2 mSv, including natural radiation; the maximum dose was 3.6 mSv. We estimated the potential annual additional effective radiation dose if people returned full-time to Iitate. Our analysis supports the plan for people to return to their home village at the end of 2017. © The Author 2015. Published by Oxford University Press on behalf of The Japan Radiation Research Society and Japanese Society for Radiation Oncology.

Collective dose estimates by the marine food pathway from liquid radioactive wastes dumped in the Sea of Japan.

PubMed

Togawa, O; Povinec, P P; Pettersson, H B

1999-09-30

IAEA-MEL has been engaged in an assessment programme related to radioactive waste dumping by the former USSR and other countries in the western North Pacific Ocean and its marginal seas. This paper focuses on the Sea of Japan and on estimation of collective doses from liquid radioactive wastes. The results from the Japanese-Korean-Russian joint expeditions are summarized, and collective doses for the Japanese population by the marine food pathway are estimated from liquid radioactive wastes dumped in the Sea of Japan and compared with those from global fallout and natural radionuclides. The collective effective dose equivalents by the annual intake of marine products caught in each year show a maximum a few years after the disposals. The total dose from all radionuclides reaches a maximum of 0.8 man Sv in 1990. Approximately 90% of the dose derives from 137Cs, most of which is due to consumption of fish. The total dose from liquid radioactive wastes is approximately 5% of that from global fallout, the contribution of which is below 0.1% of that of natural 210Po.

An updated dose assessment for resettlement options at Bikini Atoll--a U.S. nuclear test site.

PubMed

Robison, W L; Bogen, K T; Conrado, C L

1997-07-01

On 1 March 1954, a nuclear weapon test, code-named BRAVO, conducted at Bikini Atoll in the northern Marshall Islands contaminated the major residence island. There has been a continuing effort since 1977 to refine dose assessments for resettlement options at Bikini Atoll. Here we provide a radiological dose assessment for the main residence island, Bikini, using extensive radionuclide concentration data derived from analysis of food crops, ground water, cistern water, fish and other marine species, animals, air, and soil collected at Bikini Island as part of our continuing research and monitoring program that began in 1978. The unique composition of coral soil greatly alters the relative contribution of 137Cs and 90Sr to the total estimated dose relative to expectations based on North American and European soils. Without counter measures, 137Cs produces 96% of the estimated dose for returning residents, mostly through uptake from the soil to terrestrial food crops but also from external gamma exposure. The doses are calculated assuming a resettlement date of 1999. The estimated maximum annual effective dose for current island conditions is 4.0 mSv when imported foods, which are now an established part of the diet, are available. The 30-, 50-, and 70-y integral effective doses are 91 mSv, 130 mSv, and 150 mSv, respectively. A detailed uncertainty analysis for these dose estimates is presented in a companion paper in this issue. We have evaluated various countermeasures to reduce 137Cs in food crops. Treatment with potassium reduces the uptake of 137Cs into food crops, and therefore the ingestion dose, to about 5% of pretreatment levels and has essentially no negative environmental consequences. We have calculated the dose for the rehabilitation scenario where the top 40 cm of soil is removed in the housing and village area, and the rest of the island is treated with potassium fertilizer; the maximum annual effective dose is 0.41 mSv and the 30-, 50-, and 70-y integral effective doses are 9.8 mSv, 14 mSv, and 16 mSv, respectively.

Estimates of internal-dose equivalent from inhalation and ingestion of selected radionuclides

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dunning, D.E.

1982-01-01

This report presents internal radiation dose conversion factors for radionuclides of interest in environmental assessments of nuclear fuel cycles. This volume provides an updated summary of estimates of committed dose equivalent for radionuclides considered in three previous Oak Ridge National Laboratory (ORNL) reports. Intakes by inhalation and ingestion are considered. The International Commission on Radiological Protection (ICRP) Task Group Lung Model has been used to simulate the deposition and retention of particulate matter in the respiratory tract. Results corresponding to activity median aerodynamic diameters (AMAD) of 0.3, 1.0, and 5.0 ..mu..m are given. The gastorintestinal (GI) tract has been representedmore » by a four-segment catenary model with exponential transfer of radioactivity from one segment to the next. Retention of radionuclides in systemic organs is characterized by linear combinations of decaying exponential functions, recommended in ICRP Publication 30. The first-year annual dose rate, maximum annual dose rate, and fifty-year dose commitment per microcurie intake of each radionuclide is given for selected target organs and the effective dose equivalent. These estimates include contributions from specified source organs plus the systemic activity residing in the rest of the body; cross irradiation due to penetrating radiations has been incorporated into these estimates. 15 references.« less

Preliminary Results of Indoor Radon/thoron Concentrations and Terrestrial Gamma Doses in Gejiu, Yunnan, China

NASA Astrophysics Data System (ADS)

Ishikawa, Tetsuo; Tokonami, Shinji; Sun, Quafu; Kobayashi, Yosuke; Min, Xiangdong; Yoshinaga, Shinji

2008-08-01

A preliminary survey on indoor radon/thoron and external gamma ray dose rate was conducted for houses in Gejiu city and its neighboring village in Yunnan Province, China. As a result of the radon/thoron measurements for about 50 houses, very high thoron concentrations were found in some hoses (maximum: 7,900 Bq/m3). The mean annual dose from thoron decay products was estimated to be larger than that from radon decay products (2.9 mSv vs. 1.6 mSv). Further dosimetric and epidemiological studies are needed to investigate the possible effects of radon and thoron.

Finger doses for staff handling radiopharmaceuticals in nuclear medicine.

PubMed

Pant, Gauri S; Sharma, Sanjay K; Rath, Gaura K

2006-09-01

Radiation doses to the fingers of occupational workers handling 99mTc-labeled compounds and 131I for diagnostic and therapeutic procedures in nuclear medicine were measured by thermoluminescence dosimetry. The doses were measured at the base of the ring finger and the index finger of both hands in 2 groups of workers. Group 1 (7 workers) handled 99mTc-labeled radiopharmaceuticals, and group 2 (6 workers) handled 131I for diagnosis and therapy. Radiation doses to the fingertips of 3 workers also were measured. Two were from group 1, and 1 was from group 2. The doses to the base of the fingers for the radiopharmacy staff and physicians from group 1 were observed to be 17+/-7.5 (mean+/-SD) and 13.4+/-6.5 microSv/GBq, respectively. Similarly, the dose to the base of the fingers for the 3 physicians in group 2 was estimated to be 82.0+/-13.8 microSv/GBq. Finger doses for the technologists in both groups could not be calculated per unit of activity because they did not handle the radiopharmaceuticals directly. Their doses were reported in millisieverts that accumulated in 1 wk. The doses to the fingertips of the radiopharmacy worker and the physician in group 1 were 74.3+/-19.8 and 53.5+/-21.9 microSv/GBq, respectively. The dose to the fingertips of the physician in group 2 was 469.9+/-267 microSv/GBq. The radiation doses to the fingers of nuclear medicine staff at our center were measured. The maximum expected annual dose to the extremities appeared to be less than the annual limit (500 mSv/y), except for a physician who handled large quantities of 131I for treatment. Because all of these workers are on rotation and do not constantly handle radioactivity throughout the year, the doses to the base of the fingers or the fingertips should not exceed the prescribed annual limit of 500 mSv.

St. Louis Airport Site. Annual site environmental report, calendar year 1985. Formerly Utilized Sites Remedial Action Program (FUSRAP). Revision 1

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1986-09-01

During 1985, the environmental monitoring program was continued at the St. Louis Airport Site (SLAPS) in St. Louis County, Missouri. The ditches north and south of the site have been designated for cleanup as part of the Formerly Utilized Sites Remedial Action Program (FUSRAP). The monitoring program at the SLAPS measures radon gas concentrations in air; external gamma radiation dose rates; and uranium, thorium, and radium concentrations in surface water, groundwater, and sediment. Potential radiation doses to the public are also calculated. Because the site is not controlled or regulated by the DOE, the DOE Derived Concentration Guides (DCGs) aremore » not applicable to SLAPS, but are included only as a basis for comparison. The DOE DCGs and the DOE radiation protection standard have been revised. (Appendix B). During 1985, annual average radon levels in air at the SLAPS were below the DCG for uncontrolled areas. External gamma monitoring in 1985 showed measured annual gamma dose rates ranging from 3 to 2087 mrem/y, with the highest value occurring in an area known to be contaminated. The calculated maximum dose at the site boundary, assuming limited occupancy, would be 6 mrem/y. Average annual concentrations of /sup 230/Th, /sup 226/Ra, and total uranium in surface waters remained below the DOE DCG. The on-site groundwater measurements showed that average annual concentrations of /sup 230/Th, /sup 226/Ra and total uranium were within the DOE DCGs. Although there are no DCGs for sediments, all concentrations of total uraniu, /sup 230/Th, and /sup 226/Ra were below the FUSRAP Guidelines.« less

Radiation exposure assessment for portsmouth naval shipyard health studies.

PubMed

Daniels, R D; Taulbee, T D; Chen, P

2004-01-01

Occupational radiation exposures of 13,475 civilian nuclear shipyard workers were investigated as part of a retrospective mortality study. Estimates of annual, cumulative and collective doses were tabulated for future dose-response analysis. Record sets were assembled and amended through range checks, examination of distributions and inspection. Methods were developed to adjust for administrative overestimates and dose from previous employment. Uncertainties from doses below the recording threshold were estimated. Low-dose protracted radiation exposures from submarine overhaul and repair predominated. Cumulative doses are best approximated by a hybrid log-normal distribution with arithmetic mean and median values of 20.59 and 3.24 mSv, respectively. The distribution is highly skewed with more than half the workers having cumulative doses <10 mSv and >95% having doses <100 mSv. The maximum cumulative dose is estimated at 649.39 mSv from 15 person-years of exposure. The collective dose was 277.42 person-Sv with 96.8% attributed to employment at Portsmouth Naval Shipyard.

Radiation exposure to the eye lens of orthopaedic surgeons during various orthopaedic procedures.

PubMed

Romanova, K; Vassileva, J; Alyakov, M

2015-07-01

The aim of the present study was to assess the radiation dose to the eye lens of orthopaedic surgeons during various orthopaedic procedures and to make efforts to ensure that radiation protection is optimised. The study was performed for Fractura femoris and Fractura cruris procedures performed in orthopaedic operating theatres, as well as for fractures of wrist, ankle and hand/shoulder performed in the emergency trauma room. The highest mean value of the eye lens dose of 47.2 μSv and higher mean fluoroscopy time of 3 min, as well as the corresponding highest maximum values of 77.1 μSv and 5.0 min were observed for the Fractura femoris procedure performed with the Biplanar 500e fluoroscopy systems. At a normal workload, the estimated mean annual dose values do not exceed the annual occupational dose limit for the lens of eye, but at a heavy workload in the department, this dose limit could be achieved or exceeded. The use of protective lead glasses is recommended as they could reduce the radiation exposure of the lens of the eye. The phantom measurements demonstrated that the use of half-dose mode could additionally reduce dose to the operator's eye lens. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Using SAFRAN Software to Assess Radiological Hazards from Dismantling of Tammuz-2 Reactor Core at Al-tuwaitha Nuclear Site

NASA Astrophysics Data System (ADS)

Abed Gatea, Mezher; Ahmed, Anwar A.; jundee kadhum, Saad; Ali, Hasan Mohammed; Hussein Muheisn, Abbas

2018-05-01

The Safety Assessment Framework (SAFRAN) software has implemented here for radiological safety analysis; to verify that the dose acceptance criteria and safety goals are met with a high degree of confidence for dismantling of Tammuz-2 reactor core at Al-tuwaitha nuclear site. The activities characterizing, dismantling and packaging were practiced to manage the generated radioactive waste. Dose to the worker was considered an endpoint-scenario while dose to the public has neglected due to that Tammuz-2 facility is located in a restricted zone and 30m berm surrounded Al-tuwaitha site. Safety assessment for dismantling worker endpoint-scenario based on maximum external dose at component position level in the reactor pool and internal dose via airborne activity while, for characterizing and packaging worker endpoints scenarios have been done via external dose only because no evidence for airborne radioactivity hazards outside the reactor pool. The in-situ measurements approved that reactor core components are radiologically activated by Co-60 radioisotope. SAFRAN results showed that the maximum received dose for workers are (1.85, 0.64 and 1.3mSv/y) for activities dismantling, characterizing and packaging of reactor core components respectively. Hence, the radiological hazards remain below the low level hazard and within the acceptable annual dose for workers in radiation field

5 CFR 550.106 - Annual maximum earnings limitation.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 5 Administrative Personnel 1 2010-01-01 2010-01-01 false Annual maximum earnings limitation. 550... PAY ADMINISTRATION (GENERAL) Premium Pay Maximum Earnings Limitations § 550.106 Annual maximum... and premium pay for the calendar year to exceed the greater of— (1) The maximum annual rate of basic...

Gross alpha and beta activity and annual committed effective dose due to natural radionuclides in some water spinach (ipomoea aquatica Forssk) samples in Ho Chi Minh City, Vietnam.

PubMed

Le, Hao Cong; Nguyen, Thang Van; Huynh, Thu Nguyen Phong; Huynh, Phuong Truc

2017-07-01

The results of gross alpha and beta radioactivity measurement in water spinach samples from some districts in Ho Chi Minh City, Vietnam are presented in this paper. The measurements were performed using a low-background proportional counters LB4200 manufactured by Canberra Company, Inc. Mean concentrations of gross alpha and beta activity were found to be 1.50 ± 0.38 Bq kg -1 to 84.25 ± 8.67 Bq kg -1 . In order to keep the recommended dose level, a recommended maximum intake of water spinach was proposed to be 6 kg fresh per year. The total annual committed effective dose due to natural radionuclides in water spinach samples was then found in range from 0.07 mSv y -1 to 0.82 mSv y -1 . The dose from 26.32% of samples exceeds the exemption mean dose criterion of 0.3 mSv y -1 but complies with the upper dose principle of 1 mSv y -1 provided in UNSCEAR 2008 report. The estimated soil-to-plant transfer factors for gross alpha and beta for water spinach samples were also presented. Copyright © 2016 Elsevier Ltd. All rights reserved.

Watershed Regressions for Pesticides (WARP) for Predicting Annual Maximum and Annual Maximum Moving-Average Concentrations of Atrazine in Streams

USGS Publications Warehouse

Stone, Wesley W.; Gilliom, Robert J.; Crawford, Charles G.

2008-01-01

Regression models were developed for predicting annual maximum and selected annual maximum moving-average concentrations of atrazine in streams using the Watershed Regressions for Pesticides (WARP) methodology developed by the National Water-Quality Assessment Program (NAWQA) of the U.S. Geological Survey (USGS). The current effort builds on the original WARP models, which were based on the annual mean and selected percentiles of the annual frequency distribution of atrazine concentrations. Estimates of annual maximum and annual maximum moving-average concentrations for selected durations are needed to characterize the levels of atrazine and other pesticides for comparison to specific water-quality benchmarks for evaluation of potential concerns regarding human health or aquatic life. Separate regression models were derived for the annual maximum and annual maximum 21-day, 60-day, and 90-day moving-average concentrations. Development of the regression models used the same explanatory variables, transformations, model development data, model validation data, and regression methods as those used in the original development of WARP. The models accounted for 72 to 75 percent of the variability in the concentration statistics among the 112 sampling sites used for model development. Predicted concentration statistics from the four models were within a factor of 10 of the observed concentration statistics for most of the model development and validation sites. Overall, performance of the models for the development and validation sites supports the application of the WARP models for predicting annual maximum and selected annual maximum moving-average atrazine concentration in streams and provides a framework to interpret the predictions in terms of uncertainty. For streams with inadequate direct measurements of atrazine concentrations, the WARP model predictions for the annual maximum and the annual maximum moving-average atrazine concentrations can be used to characterize the probable levels of atrazine for comparison to specific water-quality benchmarks. Sites with a high probability of exceeding a benchmark for human health or aquatic life can be prioritized for monitoring.

Annual environmental monitoring report of the Lawrence Berkeley Laboratory

DOE Office of Scientific and Technical Information (OSTI.GOV)

Schleimer, G.E.

1983-04-01

In order to establish whether LBL research activities produces any impact on the population surrounding the Laboratory, a program of environmental air and water sampling and continuous radiation monitoring was carried on throughout the year. For 1982, as in the previous several years, doses attributable to LBL radiological operations were a small fraction of the relevant radiation protection guidelines (RPG). The maximum perimeter dose equivalent was less than or equal to 24.0 mrem (the 1982 dose equivalent measured at the Building 88 monitoring station B-13A, about 5% of the RPG). The total population dose equivalent attributable to LBL operations duringmore » 1982 was less than or equal to 16 man-rem, about 0.002% of the RPG of 170 mrem/person to a suitable sample of the population.« less

Radiation exposure during scoliosis screening radiography

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nottage, W.M.; Waugh, T.R.; McMaster, W.C.

Screening programs to detect scoliosis in the adolescent population are active in most communities. Two percent of children screened will be referred for treatment or observation. Increasing concern has been voiced regarding the amount of the potential effects of the radiation administered in such screening programs. Radiation dosage was directly measured on 19 children participating in an established school scoliosis screening program, using lithium fluoride thermoluminescence dosimeters. The mean gonadal doses are measured to be 19 mrem in males and estimated at a maximum 95 mrem in females. The mean entrance skin dose was 174 mrem. A lack of uniformitymore » in the radiographic techniques employed by individual technician was identified. The measured doses were within established acceptable limits and are comparable or below the average dose of 100 mrem received annually by the general public from the environment.« less

UV index experimental values during the years 2000 and 2001 from the Spanish broadband UV-B radiometric network.

PubMed

Martínez-Lozano, José A; Marín, María J; Tena, Fernando; Utrillas, María P; Sánchez-Muniosguren, Luis; González-Frías, Carlos; Cuevas, Emilio; Redondas, Alberto; Lorente, Jerónimo; de Cabo, Xavier; Cachorro, Victoria; Vergaz, Ricardo; de Frutos, Angel; Díaz, Juan P; Expósito, Francisco J; de la Morena, Benito; Vilaplana, José M

2002-08-01

An analysis is made of experimental ultraviolet erythemal solar radiation data measured during the years 2000 and 2001 by the Spanish UV-B radiation evaluation and prediction network. This network consists of 16 Robertson-Berger type pyranometers for evaluating solar erythemal radiation and five Brewer spectroradiometers for evaluating the stratospheric ozone. On the basis of these data the Ultraviolet Index (UVI) was evaluated for the measuring stations that are located either in coastal regions or in the more densely populated regions inland on the Iberian Peninsula. It has been checked that in most cases the maximum irradiance values corresponded to solar noon, although there were exceptions that could be explained by cloudiness. The maximum experimental values of the UVI were around 9 during the summer, though frequently passing this value at the inland measurement stations. The annual accumulated dose of irradiation on a horizontal plane has also been studied, as well as the evolution through the year in units of energy, standard erythemal doses and minimum erythemal doses, according to different phototypes.

Investigation of distribution of radioactivity with effects of heavy metals in toothpastes from Penang markets.

PubMed

Salih, Najeba F; Jafri, Zubir M; Jaafar, Mohamad S

2016-12-01

This study was carried out to determine the concentration of 222 Rn, 226 Ra, and 238 U in 25 different toothpastes available in the local market in Penang, Malaysia, using a CR-39 detector. The results showed the maximum concentration of radon/ radium/uranium to be 4197.644 Bq.m -3 , 54.369 Bq.Kgm -1 , and 0.044 ppm in Colgate4; the annual effective dose was found (0.402 mSvy -1 ) in S07. The average concentration of radon (42 %, 3.224 KBq.m -3 ) was higher than the concentration of 214 Po, 218 Po in POS (32 %, 2.415 KBq.m -3 ) and POW (26 %, 1.979 KBq.m -3 ). Also the values of pH of samples ranged from 4.21 (highly acidic) in S04 to 9.97 (highly basic) in S07, with an average of 6.33 which tended towards an acidic behavior; a low or high pH for a long period of time can cause harmful side-effects and enamel erosion. Concentrations of heavy metals varied from the maximum value 56.156 ppm in the Ca elements in the Colgate 4 sample to a minimum value of -0.858 ppm in the Cd elements in Colgate 6 (Ca 56.156 ppm > Cd 51.572 ppm > Zn 41.039 ppm > Mg 11.682 ppm > Pb 11.009 ppm]. Monitoring the accumulation of these metals in toothpaste samples is very important: the average annual effective dose (0.3118 mSvy -1 ) was below the range (3-10 mSvy -1 ) reported by ICRP (1993), and therefore there is no evidence of health problems. Significant strong positive correlations were found (r = 1, Pearson correlation, p < 0.000) in concentration of radon, radium, uranium, annual effective dose, pH, and electrical conductivity.

The space radiation environment

DOE Office of Scientific and Technical Information (OSTI.GOV)

Robbins, D E

There are three primary sources of space radiation: galactic cosmic rays (GCR), trapped belt radiation, and solar particle events (SPE). All are composed of ions, the nuclei of atoms. Their energies range from a few MeV u{sup -1} to over a GeV u{sup -1}. These ions can fragment when they interact with spacecraft materials and produce energetic neutrons and ions of lower atomic mass. Absorbed dose rates inside a typical spacecraft (like the Space Shuttle) in a low inclination (28.5 degrees) orbit range between 0.05 and 2 mGy d{sup -1} depending on the altitude and flight inclination (angle of orbitmore » with the equator). The quality factor of radiation in orbit depends on the relative contributions of trapped belt radiation and GCR, and the dose rate varies both with orbital altitude and inclination. The corresponding equivalent dose rate ranges between 0.1 and 4 mSv d{sup -1}. In high inclination orbits, like that of the Mir Space Station and as is planned for the International Space Station, blood-forming organ (BFO) equivalent dose rates as high as 1.5 mSv d{sup -1}. Thus, on a 1 y mission, a crew member could obtain a total dose of 0.55 Sv. Maximum equivalent dose rates measured in high altitude passes through the South Atlantic Anomaly (SAA) were 10 mSv h{sup -1}. For an interplanetary space mission (e.g., to Mars) annual doses from GCR alone range between 150 mSv y{sup -1} at solar maximum and 580 mSv y{sup -1} at solar minimum. Large SPE, like the October 1989 series, are more apt to occur in the years around solar maximum. In free space, such an event could contribute another 300 mSv, assuming that a warning system and safe haven can be effectively used with operational procedures to minimize crew exposures. Thus, the total dose for a 3 y mission to Mars could exceed 2 Sv.« less

Occurrence of 222Rn in irrigation water from Wadi Al-Rummah Qassim province, Saudi Arabia

NASA Astrophysics Data System (ADS)

El-Taher, Atef; Alashrah, Saleh

2015-08-01

Naturally accruing radioactive materials in the environment have received attention since they may be present in high level and pose risk to human health. The present work deals with measuring of 222Rn in irrigation water samples from Wadi Al-Rummah, Qassim province, in central of Saudi Arabia. 222Rn concentrations were measured by RAD7. It was found that the concentration of 222Rn ranged from 2.1 ± 1.2 to 7.2 ± 1.5 BqL-1. These values are below 11.1 BqL-1 the maximum contamination level recommended from the U.S. Environmental Protection Agency. The calculated annual effective dose (AED) ranging from 7.5 to 26.1 µSv/y. It was evident that the total annual effective dose resulting from radon in irrigation groundwater in Wadi Al-Rummah in Qassim area were significantly lower than the recommended limit 1 mSv/y for the public.

Occurrence of {sup 222}Rn in irrigation water from Wadi Al-Rummah Qassim province, Saudi Arabia

DOE Office of Scientific and Technical Information (OSTI.GOV)

El-Taher, Atef; Alashrah, Saleh

Naturally accruing radioactive materials in the environment have received attention since they may be present in high level and pose risk to human health. The present work deals with measuring of {sup 222}Rn in irrigation water samples from Wadi Al-Rummah, Qassim province, in central of Saudi Arabia. {sup 222}Rn concentrations were measured by RAD7. It was found that the concentration of {sup 222}Rn ranged from 2.1 ± 1.2 to 7.2 ± 1.5 BqL{sup −1}. These values are below 11.1 BqL{sup −1} the maximum contamination level recommended from the U.S. Environmental Protection Agency. The calculated annual effective dose (AED) ranging frommore » 7.5 to 26.1 µSv/y. It was evident that the total annual effective dose resulting from radon in irrigation groundwater in Wadi Al-Rummah in Qassim area were significantly lower than the recommended limit 1 mSv/y for the public.« less

Doses from radon 222 irradiation for workers of the granite mining industry.

PubMed

Сrygorieva, L; Tomilin, Yu

2017-12-01

determining the integral value of annual effective dose from 222Rn for workers of the granite mining industry and assessment for the expected life effective dose from 222Rn. Materials were the results of measurements of external exposure dose of radiation measurements equiv alent equilibrium volume activity of 222Rn in workrooms and workplaces of major groups of granite quarry workers Mykolaiv region, studies EROA 222Rn air premises of these workers, research content 222Rn in drinking water. Granite quarry workers receive double radiation exposure of 222Rn due to exposure in the workplace and at home. The load in the workplace due to inhalation of 222Rn the air was (2.1 ± 0.2) mSv / year (vari ation 0.9-5.9) in a residential area - (4,1 ± 0,2) mSv/year (variation 1.8-5.9). The total annual effective dose from internal exposure from air flow and working premises and drinking water was on average (6,5 ± 0,2) mSv/year, equal to a maximum value of 20 mSv/year. The expected life for the chronic exposure dose of technological naturally occurring radioactive sources for people who work in the granite quarries and, while living in high risk from radon is in the range of 0.16-1.12 Sv. The research results indicate that in assessing the effects associated with exposure due to radon 222 contingents persons such surveys must take into account all sources of this radionuclide dose. L. Сrygorieva, Yu. Tomilin.

Assessing exposure to granite countertops--Part 1: Radiation.

PubMed

Myatt, Theodore A; Allen, Joseph G; Minegishi, Taeko; McCarthy, William B; Stewart, James H; Macintosh, David L; McCarthy, John F

2010-05-01

Humans are continuously exposed to low levels of ionizing radiation. Known sources include radon, soil, cosmic rays, medical treatment, food, and building products such as gypsum board and concrete. Little information exists about radiation emissions and associated doses from natural stone finish materials such as granite countertops in homes. To address this knowledge gap, gross radioactivity, gamma ray activity, and dose rate were determined for slabs of granite marketed for use as countertops. Annual effective radiation doses were estimated from measured dose rates and human activity patterns while accounting for the geometry of granite countertops in a model kitchen. Gross radioactivity, gamma activity, and dose rate varied significantly among and within slabs of granite with ranges for median levels at the slab surface of ND to 3000 cpm, ND to 98,000 cpm, and ND to 1.5E-4 mSv/h, respectively. The maximum activity concentrations of the (40)K, (232)Th, and (226)Ra series were 2715, 231, and 450 Bq/kg, respectively. The estimated annual radiation dose from spending 4 h/day in a hypothetical kitchen ranged from 0.005 to 0.18 mSv/a depending on the type of granite. In summary, our results show that the types of granite characterized in this study contain varying levels of radioactive isotopes and that their observed emissions are consistent with those reported in the scientific literature. We also conclude from our analyses that these emissions are likely to be a minor source of external radiation dose when used as countertop material within the home and present a negligible risk to human health.

Assessment of eye lens doses for workers during interventional radiology procedures.

PubMed

Urboniene, A; Sadzeviciene, E; Ziliukas, J

2015-07-01

The assessment of eye lens doses for workers during interventional radiology (IR) procedures was performed using a new eye lens dosemeter. In parallel, the results of routine individual monitoring were analysed and compared with the results obtained from measurements with a new eye lens dosemeter. The eye lens doses were assessed using Hp(3) measured at the level of the eyes and were compared with Hp(10) measured with the whole-body dosemeter above the lead collar. The information about use of protective measures, the number of performed interventional procedures per month and their fluoroscopy time was also collected. The assessment of doses to the lens of the eye was done for 50 IR workers at 9 Lithuanian hospitals for the period of 2012-2013. If the use of lead glasses is not taken into account, the estimated maximum annual dose equivalent to the lens of the eye was 82 mSv. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Monte Carlo simulations of the secondary neutron ambient and effective dose equivalent rates from surface to suborbital altitudes and low Earth orbit

NASA Astrophysics Data System (ADS)

El-Jaby, Samy; Richardson, Richard B.

2015-07-01

Occupational exposures from ionizing radiation are currently regulated for airline travel (<20 km) and for missions to low-Earth orbit (∼300-400 km). Aircrew typically receive between 1 and 6 mSv of occupational dose annually, while aboard the International Space Station, the area radiation dose equivalent measured over just 168 days was 106 mSv at solar minimum conditions. It is anticipated that space tourism vehicles will reach suborbital altitudes of approximately 100 km and, therefore, the annual occupational dose to flight crew during repeated transits is expected to fall somewhere between those observed for aircrew and astronauts. Unfortunately, measurements of the radiation environment at the high altitudes reached by suborbital vehicles are sparse, and modelling efforts have been similarly limited. In this paper, preliminary MCNPX radiation transport code simulations are developed of the secondary neutron flux profile in air from surface altitudes up to low Earth orbit at solar minimum conditions and excluding the effects of spacecraft shielding. These secondary neutrons are produced by galactic cosmic radiation interacting with Earth's atmosphere and are among the sources of radiation that can pose a health risk. Associated estimates of the operational neutron ambient dose equivalent, used for radiation protection purposes, and the neutron effective dose equivalent that is typically used for estimates of stochastic health risks, are provided in air. Simulations show that the neutron radiation dose rates received at suborbital altitudes are comparable to those experienced by aircrew flying at 7 to 14 km. We also show that the total neutron dose rate tails off beyond the Pfotzer maximum on ascension from surface up to low Earth orbit.

Monte Carlo simulations of the secondary neutron ambient and effective dose equivalent rates from surface to suborbital altitudes and low Earth orbit.

PubMed

El-Jaby, Samy; Richardson, Richard B

2015-07-01

Occupational exposures from ionizing radiation are currently regulated for airline travel (<20 km) and for missions to low-Earth orbit (∼300-400 km). Aircrew typically receive between 1 and 6 mSv of occupational dose annually, while aboard the International Space Station, the area radiation dose equivalent measured over just 168 days was 106 mSv at solar minimum conditions. It is anticipated that space tourism vehicles will reach suborbital altitudes of approximately 100 km and, therefore, the annual occupational dose to flight crew during repeated transits is expected to fall somewhere between those observed for aircrew and astronauts. Unfortunately, measurements of the radiation environment at the high altitudes reached by suborbital vehicles are sparse, and modelling efforts have been similarly limited. In this paper, preliminary MCNPX radiation transport code simulations are developed of the secondary neutron flux profile in air from surface altitudes up to low Earth orbit at solar minimum conditions and excluding the effects of spacecraft shielding. These secondary neutrons are produced by galactic cosmic radiation interacting with Earth's atmosphere and are among the sources of radiation that can pose a health risk. Associated estimates of the operational neutron ambient dose equivalent, used for radiation protection purposes, and the neutron effective dose equivalent that is typically used for estimates of stochastic health risks, are provided in air. Simulations show that the neutron radiation dose rates received at suborbital altitudes are comparable to those experienced by aircrew flying at 7 to 14 km. We also show that the total neutron dose rate tails off beyond the Pfotzer maximum on ascension from surface up to low Earth orbit. Crown Copyright © 2015. Published by Elsevier Ltd. All rights reserved.

Radon and Thoron In-air Occupational Exposure Study within Selected Wine Cellars of the Western Cape (South Africa) and Associated Annual Effective Doses.

PubMed

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

2017-01-01

This is the first known study of exposure of Rn (radon) and secondarily Rn (thoron) in-air activity concentrations assessed within nine selected wine cellars in four wine districts of the Western Cape (South Africa) and the associated annual occupational effective doses. E-PERM electret ion chambers (EIC) and RAD-7 α-detectors were used to perform these measurements. The radon in-air levels ranged from 12 ± 4 Bq m to 770 ± 40 Bq m within the nine selected wine cellars. Eight of the nine wine cellars (excluding results from cellar w-6) had a median radon in-air activity concentration of 48 ± 8 Bq m. Continuous thoron in-air activity concentration levels were also measured near an internal granite wall of the wine cellar w-6 (barrel room), where peak levels of up to 1,520 ± 190 Bq m and an average of 680 ± 30 Bq m were observed. The occupational annual effective dose due to radon and decay progeny exposure in-air within the selected wine cellars ranged from 0.08 ± 0.03 mSv to 4.9 ± 0.3 mSv with a median of 0.32 ± 0.04 mSv (Tmax = 2,000 h). The annual effective dose within the wine cellar (w-6) ranged up to a maximum of 2.5 ± 0.4 mSv (Tmax = 2000 h) due to exposure to thoron and decay progeny. In general, most of the wines cellars pose negligible associated health risk to personnel due to ionizing radiation exposure from the inhalation of radon and progeny. Under certain conditions (proximity and exposure time), caution should be exercised at wine cellar w-6 because of elevated thoron in-air levels.

Drinking water standard for tritium-what's the risk?

PubMed

Kocher, D C; Hoffman, F O

2011-09-01

This paper presents an assessment of lifetime risks of cancer incidence associated with the drinking water standard for tritium established by the U.S. Environmental Protection Agency (USEPA); this standard is an annual-average maximum contaminant level (MCL) of 740 Bq L(-1). This risk assessment has several defining characteristics: (1) an accounting of uncertainty in all parameters that relate a given concentration of tritium in drinking water to lifetime risk (except the number of days of consumption of drinking water in a year and the number of years of consumption) and an accounting of correlations of uncertain parameters to obtain probability distributions that represent uncertainty in estimated lifetime risks of cancer incidence; (2) inclusion of a radiation effectiveness factor (REF) to represent an increased biological effectiveness of low-energy electrons emitted in decay of tritium compared with high-energy photons; (3) use of recent estimates of risks of cancer incidence from exposure to high-energy photons, including the dependence of risks on an individual's gender and age, in the BEIR VII report; and (4) inclusion of risks of incidence of skin cancer, principally basal cell carcinoma. By assuming ingestion of tritium in drinking water at the MCL over an average life expectancy of 80 y in females and 75 y in males, 95% credibility intervals of lifetime risks of cancer incidence obtained in this assessment are (0.35, 12) × 10(-4) in females and (0.30, 15) × 10(-4) in males. Mean risks, which are considered to provide the best single measure of expected risks, are about 3 × 10(-4) in both genders. In comparison, USEPA's point estimate of the lifetime risk of cancer incidence, assuming a daily consumption of drinking water of 2 L over an average life expectancy of 75.2 y and excluding an REF for tritium and incidence of skin cancer, is 5.6 × 10(-5). Probability distributions of annual equivalent doses to the whole body associated with the drinking water standard for tritium also were obtained. Means and 97.5th percentiles of maximum annual doses to females and males, which occur at age <1 y, all are less than the annual equivalent dose of 40 μSv used by USEPA to establish the MCL.

The effect of work system on the hand exposure of workers in 18F-FDG production centres.

PubMed

Wrzesień, Małgorzata

2018-05-07

The production of the 18 F isotope-the marker of deoxyglucose ( 18 F-FDG)-the radiopharmaceutical most commonly used in the oncological diagnostic technique of positron emission tomography, requires a cyclotron device. At present, there are nine facilities working in Poland that are equipped with cyclotrons used for producing the short-lived isotopes. The aim of the paper is to determine the hand exposure of workers employed in the two 18 F-FDG production centres taking in to account the production procedures and work system in those facilities. Measurements, which included all professional workers exposed to ionizing radiation that were employed in two facilities, were performed by using high-sensitivity thermoluminescent detectors during the routine activities of the personnel. The work system used at the production centre has an impact on the level of the recorded doses. Among the production procedures performed by the staff, the highest ionizing radiation doses have been received by the staff during the 18 F-FDG quality control. The maximum estimated annual Hp(0.07) for chemists from the quality control department can exceed the annual skin limit dose (500 mSv). The source of lowest doses on the hands are the cyclotron operating procedure and the 18 F-FDG production, provided that these procedures can't be combined with other production procedures.

A comprehensive dose reconstruction methodology for former rocketdyne/atomics international radiation workers.

PubMed

Boice, John D; Leggett, Richard W; Ellis, Elizabeth Dupree; Wallace, Phillip W; Mumma, Michael; Cohen, Sarah S; Brill, A Bertrand; Chadda, Bandana; Boecker, Bruce B; Yoder, R Craig; Eckerman, Keith F

2006-05-01

Incomplete radiation exposure histories, inadequate treatment of internally deposited radionuclides, and failure to account for neutron exposures can be important uncertainties in epidemiologic studies of radiation workers. Organ-specific doses from lifetime occupational exposures and radionuclide intakes were estimated for an epidemiologic study of 5,801 Rocketdyne/Atomics International (AI) radiation workers engaged in nuclear technologies between 1948 and 1999. The entire workforce of 46,970 Rocketdyne/AI employees was identified from 35,042 Kardex work histories cards, 26,136 electronic personnel listings, and 14,189 radiation folders containing individual exposure histories. To obtain prior and subsequent occupational exposure information, the roster of all workers was matched against nationwide dosimetry files from the Department of Energy, the Nuclear Regulatory Commission, the Landauer dosimetry company, the U.S. Army, and the U.S. Air Force. Dosimetry files of other worker studies were also accessed. Computation of organ doses from radionuclide intakes was complicated by the diversity of bioassay data collected over a 40-y period (urine and fecal samples, lung counts, whole-body counts, nasal smears, and wound and incident reports) and the variety of radionuclides with documented intake including isotopes of uranium, plutonium, americium, calcium, cesium, cerium, zirconium, thorium, polonium, promethium, iodine, zinc, strontium, and hydrogen (tritium). Over 30,000 individual bioassay measurements, recorded on 11 different bioassay forms, were abstracted. The bioassay data were evaluated using ICRP biokinetic models recommended in current or upcoming ICRP documents (modified for one inhaled material to reflect site-specific information) to estimate annual doses for 16 organs or tissues taking into account time of exposure, type of radionuclide, and excretion patterns. Detailed internal exposure scenarios were developed and annual internal doses were derived on a case-by-case basis for workers with committed equivalent doses indicated by screening criteria to be greater than 10 mSv to the organ with the highest internal dose. Overall, 5,801 workers were monitored for radiation at Rocketdyne/AI: 5,743 for external exposure and 2,232 for internal intakes of radionuclides; 41,169 workers were not monitored for radiation. The mean cumulative external dose based on Rocketdyne/AI records alone was 10.0 mSv, and the dose distribution was highly skewed with most workers experiencing low cumulative doses and only a few with high doses (maximum 500 mSv). Only 45 workers received greater than 200 mSv while employed at Rocketdyne/AI. However, nearly 32% (or 1,833) of the Rocketdyne/AI workers had been monitored for radiation at other nuclear facilities and incorporation of these doses increased the mean dose to 13.5 mSv (maximum 1,005 mSv) and the number of workers with >200 mSv to 69. For a small number of workers (n=292), lung doses from internal radionuclide intakes were relatively high (mean 106 mSv; maximum 3,560 mSv) and increased the overall population mean dose to 19.0 mSv and the number of workers with lung dose>200 mSv to 109. Nearly 10% of the radiation workers (584) were monitored for neutron exposures (mean 1.2 mSv) at Rocketdyne/AI, and another 2% were monitored for neutron exposures elsewhere. Interestingly, 1,477 workers not monitored for radiation at Rocketdyne/AI (3.6%) were found to have worn dosimeters at other nuclear facilities (mean external dose of 2.6 mSv, maximum 188 mSv). Without considering all sources of occupational exposure, an incorrect characterization of worker exposure would have occurred with the potential to bias epidemiologic results. For these pioneering workers in the nuclear industry, 26.5% of their total occupational dose (collective dose) was received at other facilities both prior to and after employment at Rocketdyne/AI. In addition, a small number of workers monitored for internal radionuclides contributed disproportionately to the number of workers with high lung doses. Although nearly 12% of radiation workers had been monitored for neutron exposures during their career, the cumulative dose levels were small in comparison with other external and internal exposure. Risk estimates based on nuclear worker data must be interpreted cautiously if internally deposited radionuclides and occupational doses received elsewhere are not considered.

Leaded eyeglasses substantially reduce radiation exposure of the surgeon's eyes during acquisition of typical fluoroscopic views of the hip and pelvis.

PubMed

Burns, Sean; Thornton, Raymond; Dauer, Lawrence T; Quinn, Brian; Miodownik, Daniel; Hak, David J

2013-07-17

Despite recommendations to do so, few orthopaedists wear leaded glasses when performing operative fluoroscopy. Radiation exposure to the ocular lens causes cataracts, and regulatory limits for maximum annual occupational exposure to the eye continue to be revised downward. Using anthropomorphic patient and surgeon phantoms, radiation dose at the surgeon phantom's lens was measured with and without leaded glasses during fluoroscopic acquisition of sixteen common pelvic and hip views. The magnitude of lens dose reduction from leaded glasses was calculated by dividing the unprotected dose by the dose measured behind leaded glasses. On average, the use of leaded glasses reduced radiation to the surgeon phantom's eye by tenfold, a 90% reduction in dose. However, there was widespread variation in the amount of radiation that reached the phantom surgeon's eye among the various radiographic projections we studied. Without leaded glasses, the dose measured at the surgeon's lens varied more than 250-fold among these sixteen different views. In addition to protecting the surgeon's eye from the deleterious effects of radiation, the use of leaded glasses could permit an orthopaedist to perform fluoroscopic views on up to ten times more patients before reaching the annual dose limit of 20 mSv of radiation to the eye recommended by the International Commission on Radiological Protection. Personal safety and adherence to limits of occupational radiation exposure should compel orthopaedists to wear leaded glasses for fluoroscopic procedures if other protective barriers are not in use. Leaded glasses are a powerful tool for reducing the orthopaedic surgeon's lens exposure to radiation during acquisition of common intraoperative fluoroscopic views.

Radiological assessment of Abu-Tartur phosphate, Western Desert Egypt.

PubMed

Uosif, M A M; El-Taher, A

2008-01-01

The contents of natural radionuclides ((226)Ra, (232)Th and (40)K) were measured in sedimentary phosphate rock samples (Abu-Tartur phosphate, Western Desert Egypt) by using gamma spectrometry (NaI (Tl) 3"x 3"). Phosphate and environmental samples were collected from Abu-Tartur phosphate mine and the surrounding region. The results are discussed and compared with the levels in phosphate rocks from different countries. The activities of (226)Ra, (232)Th series and (40)K are between (14.9 +/- 0.8 and 302.4 +/- 15.2), (2.6 +/- 1.0 and 154.9 +/- 7.8) and (10.0 +/- 0.5 and 368.4 +/- 18.4) Bq kg(-1), respectively. The Abu-Tartur phosphate deposit was found to have lower activity than many others exploited phosphate sedimentary deposits, with its average total annual dose being only 114.6 microSv y(-1). This value is about 11.46% of the 1.0 mSv y(-1) recommended by the International Commission on Radiological Protection (ICRP-60, 1990) as the maximum annual dose to members of the public.

Radon activity concentrations and effective doses in ancient Egyptian tombs of the Valley of the Kings.

PubMed

Hafez, A F; Hussein, A S

2001-09-01

Radon concentrations and equilibrium factors were measured in three pharaonic tombs during the year 1998. The tombs, which are open to the public are located in a limestone wadi on the West Bank of the River Nile at Luxor, 650 km south of Cairo. The radon activity concentration and equilibrium factor were measured monthly by two-integral nuclear track detectors (bare and diffusion detectors). Seasonal variation of radon concentrations, with summer maximum and winter minimum were observed in all tombs investigated. The yearly mean radon activity concentrations insidc the tombs ranged from 540 to 3115 Bq m(-3). The mean equilibrium factor over a year was found to be 0.25 and 0.32 inside and at the entrance, respectively. Estimated annual effective doses to tour guides ranged from 0.33 to 1.90 mSv, visitors receive doses from 0.65 to 3.80 microSv per visit. The effective dose to tomb workers did not exceed the 20 mSv yr(-1) limit.

Measurement of 238U and 232Th in Petrol, Gas-oil and Lubricant Samples by Using Nuclear Track Detectors and Resulting Radiation Doses to the Skin of Mechanic Workers.

PubMed

Misdaq, M A; Chaouqi, A; Ouguidi, J; Touti, R; Mortassim, A

2015-10-01

Workers in repair shops of vehicles (cars, buses, truck, etc.) clean carburetors, check fuel distribution, and perform oil changes and greasing. To explore the exposure pathway of (238)U and (232)Th and its decay products to the skin of mechanic workers, these radionuclides were measured inside petrol, gas-oil, and lubricant material samples by means of CR-39 and LR-115 type II solid state nuclear track detectors (SSNTDs), and corresponding annual committed equivalent doses to skin were determined. The maximum total equivalent effective dose to skin due to the (238)U and (232)Th series from the application of different petrol, gas-oil, and lubricant samples by mechanic workers was found equal to 1.2 mSv y(-1) cm(-2).

76 FR 53847 - New International Commission on Radiological Protection; Recommendations on the Annual Dose Limit...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-08-30

... Radiological Protection; Recommendations on the Annual Dose Limit to the Lens of the Eye AGENCY: Nuclear... Protection (ICRP) recommendations for the limitation of annual dose to the lens of the eye. This significant... might be lower than previously considered. For the lens of the eye, the threshold in absorbed dose for...

The Optimal Forest Rotation: A Discussion and Annotated Bibliography

Treesearch

David H. Newman

1988-01-01

The literature contains six different criteria of the optimal forest rotation: (1) maximum single-rotation physical yield, (2) maximum single-rotation annual yield, (3) maximum single-rotation discounted net revenues, (4) maximum discounted net revenues from an infinite series of rotations, (5) maximum annual net revenues, and (6) maximum internal rate of return. First...

Deposition and dose from the 18 May 1980 eruption of Mount St. Helens

NASA Technical Reports Server (NTRS)

Peterson, K. R.

1982-01-01

The downwind deposition and radiation doses was calculated for the tropospheric part of the ash cloud from the May 18, 1980 eruption of Mount St. Helens, by using a large cloud diffusion model. The naturally occurring radionnuclides of radium and thorium, whose radon daughters normally seep very slowly from the rocks and soil, were violently released to the atmosphere. The largest dose to an individual from these nuclides is small, but the population dose to those affected by the radioactivity in the ash is about 100 person rem. This population dose from Mount St. Helens is much greater than the annual person rem routinely released by a typical large nuclear power plant. It is estimated that subsequent eruptions of Mount St. Helens have doubled or tripled the person rem calculated from the initial large eruption. The long range global ash deposition of the May 18 eruption is estimated through 1984, by use of a global deposition model. The maximum deposition is nearly 1000 kg square km and occurs in the spring of 1981 over middle latitudes of the Northern Hemisphere.

Historical Doses from Tritiated Water and Tritiated Hydrogen Gas Released to the Atmosphere from Lawrence Livermore National Laboratory (LLNL). Part 5. Accidental Releases

DOE Office of Scientific and Technical Information (OSTI.GOV)

Peterson, S

2007-08-15

Over the course of fifty-three years, LLNL had six acute releases of tritiated hydrogen gas (HT) and one acute release of tritiated water vapor (HTO) that were too large relative to the annual releases to be included as part of the annual releases from normal operations detailed in Parts 3 and 4 of the Tritium Dose Reconstruction (TDR). Sandia National Laboratories/California (SNL/CA) had one such release of HT and one of HTO. Doses to the maximally exposed individual (MEI) for these accidents have been modeled using an equation derived from the time-dependent tritium model, UFOTRI, and parameter values based onmore » expert judgment. All of these acute releases are described in this report. Doses that could not have been exceeded from the large HT releases of 1965 and 1970 were calculated to be 43 {micro}Sv (4.3 mrem) and 120 {micro}Sv (12 mrem) to an adult, respectively. Two published sets of dose predictions for the accidental HT release in 1970 are compared with the dose predictions of this TDR. The highest predicted dose was for an acute release of HTO in 1954. For this release, the dose that could not have been exceeded was estimated to have been 2 mSv (200 mrem), although, because of the high uncertainty about the predictions, the likely dose may have been as low as 360 {micro}Sv (36 mrem) or less. The estimated maximum exposures from the accidental releases were such that no adverse health effects would be expected. Appendix A lists all accidents and large routine puff releases that have occurred at LLNL and SNL/CA between 1953 and 2005. Appendix B describes the processes unique to tritium that must be modeled after an acute release, some of the time-dependent tritium models being used today, and the results of tests of these models.« less

Occupational dose in interventional radiology procedures.

PubMed

Chida, Koichi; Kaga, Yuji; Haga, Yoshihiro; Kataoka, Nozomi; Kumasaka, Eriko; Meguro, Taiichiro; Zuguchi, Masayuki

2013-01-01

Interventional radiology tends to involve long procedures (i.e., long fluoroscopic times). Therefore, radiation protection for interventional radiology staff is an important issue. This study describes the occupational radiation dose for interventional radiology staff, especially nurses, to clarify the present annual dose level for interventional radiology nurses. We compared the annual occupational dose (effective dose and dose equivalent) among interventional radiology staff in a hospital where 6606 catheterization procedures are performed annually. The annual occupational doses of 18 physicians, seven nurses, and eight radiologic technologists were recorded using two monitoring badges, one worn over and one under their lead aprons. The annual mean ± SD effective dose (range) to the physicians, nurses, and radiologic technologists using two badges was 3.00 ± 1.50 (0.84-6.17), 1.34 ± 0.55 (0.70-2.20), and 0.60 ± 0.48 (0.02-1.43) mSv/y, respectively. Similarly, the annual mean ± SD dose equivalent range was 19.84 ± 12.45 (7.0-48.5), 4.73 ± 0.72 (3.9-6.2), and 1.30 ± 1.00 (0.2-2.7) mSv/y, respectively. The mean ± SD effective dose for the physicians was 1.02 ± 0.74 and 3.00 ± 1.50 mSv/y for the one- and two-badge methods, respectively (p < 0.001). Similarly, the mean ± SD effective dose for the nurses (p = 0.186) and radiologic technologists (p = 0.726) tended to be lower using the one-badge method. The annual occupational dose for interventional radiology staff was in the order physicians > nurses > radiologic technologists. The occupational dose determined using one badge under the apron was far lower than the dose obtained with two badges in both physicians and nonphysicians. To evaluate the occupational dose correctly, we recommend use of two monitoring badges to evaluate interventional radiology nurses as well as physicians.

Stochastic characteristics of different duration annual maximum rainfall and its spatial difference in China based on information entropy

NASA Astrophysics Data System (ADS)

Li, X.; Sang, Y. F.

2017-12-01

Mountain torrents, urban floods and other disasters caused by extreme precipitation bring great losses to the ecological environment, social and economic development, people's lives and property security. So there is of great significance to floods prevention and control by the study of its spatial distribution. Based on the annual maximum rainfall data of 60min, 6h and 24h, the paper generate long sequences following Pearson-III distribution, and then use the information entropy index to study the spatial distribution and difference of different duration. The results show that the information entropy value of annual maximum rainfall in the south region is greater than that in the north region, indicating more obvious stochastic characteristics of annual maximum rainfall in the latter. However, the spatial distribution of stochastic characteristics is different in different duration. For example, stochastic characteristics of 60min annual maximum rainfall in the Eastern Tibet is smaller than surrounding, but 6h and 24h annual maximum rainfall is larger than surrounding area. In the Haihe River Basin and the Huaihe River Basin, the stochastic characteristics of the 60min annual maximum rainfall was not significantly different from that in the surrounding area, and stochastic characteristics of 6h and 24h was smaller than that in the surrounding area. We conclude that the spatial distribution of information entropy values of annual maximum rainfall in different duration can reflect the spatial distribution of its stochastic characteristics, thus the results can be an importantly scientific basis for the flood prevention and control, agriculture, economic-social developments and urban flood control and waterlogging.

Identification of "ever-cropped" land (1984-2010) using Landsat annual maximum NDVI image composites: Southwestern Kansas case study.

PubMed

Maxwell, Susan K; Sylvester, Kenneth M

2012-06-01

A time series of 230 intra- and inter-annual Landsat Thematic Mapper images was used to identify land that was ever cropped during the years 1984 through 2010 for a five county region in southwestern Kansas. Annual maximum Normalized Difference Vegetation Index (NDVI) image composites (NDVI(ann-max)) were used to evaluate the inter-annual dynamics of cropped and non-cropped land. Three feature images were derived from the 27-year NDVI(ann-max) image time series and used in the classification: 1) maximum NDVI value that occurred over the entire 27 year time span (NDVI(max)), 2) standard deviation of the annual maximum NDVI values for all years (NDVI(sd)), and 3) standard deviation of the annual maximum NDVI values for years 1984-1986 (NDVI(sd84-86)) to improve Conservation Reserve Program land discrimination.Results of the classification were compared to three reference data sets: County-level USDA Census records (1982-2007) and two digital land cover maps (Kansas 2005 and USGS Trends Program maps (1986-2000)). Area of ever-cropped land for the five counties was on average 11.8 % higher than the area estimated from Census records. Overall agreement between the ever-cropped land map and the 2005 Kansas map was 91.9% and 97.2% for the Trends maps. Converting the intra-annual Landsat data set to a single annual maximum NDVI image composite considerably reduced the data set size, eliminated clouds and cloud-shadow affects, yet maintained information important for discriminating cropped land. Our results suggest that Landsat annual maximum NDVI image composites will be useful for characterizing land use and land cover change for many applications.

Public member dose assessment of Bushehr Nuclear Power Plant under normal operation by modeling the fallout from stack using the HYSPLIT atmospheric dispersion model.

PubMed

Zali, A; Shamsaei Zafarghandi, M; Feghhi, S A; Taherian, A M

2017-05-01

In this work, public dose resulting from fission products released from Bushehr Nuclear Power Plant (BNPP) under normal operation is assessed. Due to the long range transport of radionuclides in this work (80 km) and considering terrain and meteorological data, HYbrid Single-Particle Lagrangian Integrated Trajectory (HYsplit) model, which uses three dimensional long-range numerical models, has been employed to calculate atmospheric dispersion. Annual effective dose calculation is carried out for inhalation, ingestion, and external exposure pathways in 16directions and within 80 km around the site for representative person. The results showed the maximum dose of inhalation and external exposure for adults is 3.8 × 10 -8 Sv/y in the SE direction and distance of 600 m from the BNPP site which is less than ICRP 103 recommended dose limit (1 mSv). Children and infants' doses are higher in comparison with adults, although they are less than 1 mSv. Ingestion dose percentage in the total dose is less than 0.1%. The results of this study underestimate the Final Safety Analysis Report ofBNPP-1 (FSAR)data. Copyright © 2017 Elsevier Ltd. All rights reserved.

Weldon Spring Site environmental report for calendar year 1993. Weldon Springs Site Remedial Action Project

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1994-05-01

This Site Environmental Report for Calendar Year 1993 describes the environmental monitoring programs at the Weldon Spring Site Remedial Action Project (WSSRAP). The objectives of these programs are to assess actual or potential exposure to contaminant effluents from the project area by providing public use scenarios and dose estimates, to demonstrate compliance with Federal and State permitted levels, and to summarize trends and/or changes in contaminant concentrations from environmental monitoring program. In 1993, the maximum committed dose to a hypothetical individual at the chemical plant site perimeter was 0.03 mrem (0.0003 mSv). The maximum committed dose to a hypothetical individualmore » at the boundary of the Weldon Spring Quarry was 1.9 mrem (0.019 mSv). These scenarios assume an individual walking along the perimeter of the site-once a day at the chemical plant/raffinate pits and twice a day at the quarry-250 days per year. This hypothetical individual also consumes fish, sediment, and water from lakes and other bodies of water in the area. The collective dose, based on an effected population of 112,000 was 0.12 person-rem (0.0012 person-Sv). This calculation is based on recreational use of the August A. Busch Memorial Conservation Area and the Missouri Department of Conservation recreational trail (the Katy Trail) near the quarry. These estimates are below the U.S. Department of Energy requirement of 100 mrem (I mSv) annual committed effective dose equivalent for all exposure pathways. Results from air monitoring for the National Emission Standards for Hazardous Air Pollutants (NESHAPs) program indicated that the estimated dose was 0.38 mrem, which is below the U.S. Environmental Protection Agency (EPA) standard of 10 mrem per year.« less

On the Trend of the Annual Mean, Maximum, and Minimum Temperature and the Diurnal Temperature Range in the Armagh Observatory, Northern Ireland, Dataset, 1844 -2012

NASA Technical Reports Server (NTRS)

Wilson, Robert M.

2013-01-01

Examined are the annual averages, 10-year moving averages, decadal averages, and sunspot cycle (SC) length averages of the mean, maximum, and minimum surface air temperatures and the diurnal temperature range (DTR) for the Armagh Observatory, Northern Ireland, during the interval 1844-2012. Strong upward trends are apparent in the Armagh surface-air temperatures (ASAT), while a strong downward trend is apparent in the DTR, especially when the ASAT data are averaged by decade or over individual SC lengths. The long-term decrease in the decadaland SC-averaged annual DTR occurs because the annual minimum temperatures have risen more quickly than the annual maximum temperatures. Estimates are given for the Armagh annual mean, maximum, and minimum temperatures and the DTR for the current decade (2010-2019) and SC24.

24 CFR 883.604 - Maximum annual commitment and project account.

Code of Federal Regulations, 2011 CFR

2011-04-01

... annual commitment. The maximum annual contribution that may be contracted for in the ACC is the total of... annual commitment exceeds the amount actually paid out under the ACC each year. Payments will be made... specifically approved by the Secretary. (2) Whenever a HUD-approved estimate of required payments under the ACC...

24 CFR 883.604 - Maximum annual commitment and project account.

Code of Federal Regulations, 2010 CFR

2010-04-01

... annual commitment. The maximum annual contribution that may be contracted for in the ACC is the total of... annual commitment exceeds the amount actually paid out under the ACC each year. Payments will be made... specifically approved by the Secretary. (2) Whenever a HUD-approved estimate of required payments under the ACC...

Radon Concentration And Dose Assessment In Well Water Samples From Karbala Governorate Of Iraq

NASA Astrophysics Data System (ADS)

Al-Alawy, I. T.; Hasan, A. A.

2018-05-01

There are numerous studies around the world about radon concentrations and their risks to the health of human beings. One of the most important social characteristics is the use of water wells for irrigation, which is a major source of water pollution with radon gas. In the present study, six well water samples have been collected from different locations in Karbala governorate to investigate radon concentration level using CR-39 technique. The maximum value 4.112±2.0Bq/L was in Al-Hurr (Al-Qarih Al-Easariah) region, and the lowest concentration of radon was in Hay Ramadan region which is 2.156±1.4Bq/L, with an average value 2.84±1.65Bq/L. The highest result of annual effective dose (AED) was in Al-Hurr (Al-Qarih Al-Easariah) region which is equal to 15.00±3.9μSv/y, while the minimum was recorded in Hay Ramadan 7.86±2.8μSv/y, with an average value 10.35±3.1μSv/y. The current results have shown that the radon concentrations in well water samples are lower than the recommended limit 11.1Bq/L and the annual effective dose in these samples are lower than the permissible international limit 1mSv/y.

Ten years of measured UV Index from the Spanish UVB Radiometric Network.

PubMed

Utrillas, M P; Marín, M J; Esteve, A R; Estellés, V; Gandía, S; Núnez, J A; Martínez-Lozano, J A

2013-08-05

An analysis is made of the UV Index (UVI) obtained from the ultraviolet erythemal solar radiation (UVER) data measured by the Spanish UVB Radiometric Network between the years 2000 and 2009. Previously, the daily UVI has been evaluated using two different criteria: (a) the value corresponding to solar noon; and (b) the daily maximum value. The mean percentage of agreement is 92% if we consider the cases for which the difference is zero or one UVI unit. These results are similar to those obtained in a previous work where only 2 years were analyzed. In all the stations the UVI reaches very high values (8-10) in spring-summer, and the very high and extreme (≥ 11) UVI values are more dependent on the continental effect than on the latitude effect. From the UVI values it is possible to classify the stations into four groups: Coastal stations, Continental stations (more than 200 km from the coast), Southern stations (Coastal stations but with similar values of UVI as the Continental ones due to their low latitude) and Canary Islands stations (1400 km southwest from the Iberian Peninsula thus lower latitude). The monthly mean maximum of UVI is reached in July due to the annual evolution of the total ozone column. This value corresponds, for a skin phototype II, to three times the minimal erythemal dose (MED) in an hour in a Coastal station, 3.5 MEDs in an hour measured in a Continental or Southern station and up five MEDs in an hour in the Izaña station (Canary Islands). The cumulative dose on a horizontal plane over an average year has been calculated for each station. More than 40% of the annual dose is received in summer, about 35% in spring, more than 11% in autumn and less than 10% in winter except for the stations in the Canary Islands where the difference between seasons is less significant. Copyright © 2013 Elsevier B.V. All rights reserved.

Estimated radiation exposure of German commercial airline cabin crew in the years 1960-2003 modeled using dose registry data for 2004-2015.

PubMed

Wollschläger, Daniel; Hammer, Gaël Paul; Schafft, Thomas; Dreger, Steffen; Blettner, Maria; Zeeb, Hajo

2018-05-01

Exposure to ionizing radiation of cosmic origin is an occupational risk factor in commercial aircrew. In a historic cohort of 26,774 German aircrew, radiation exposure was previously estimated only for cockpit crew using a job-exposure matrix (JEM). Here, a new method for retrospectively estimating cabin crew dose is developed. The German Federal Radiation Registry (SSR) documents individual monthly effective doses for all aircrew. SSR-provided doses on 12,941 aircrew from 2004 to 2015 were used to model cabin crew dose as a function of age, sex, job category, solar activity, and male pilots' dose; the mean annual effective dose was 2.25 mSv (range 0.01-6.39 mSv). In addition to an inverse association with solar activity, exposure followed age- and sex-dependent patterns related to individual career development and life phases. JEM-derived annual cockpit crew doses agreed with SSR-provided doses for 2004 (correlation 0.90, 0.40 mSv root mean squared error), while the estimated average annual effective dose for cabin crew had a prediction error of 0.16 mSv, equaling 7.2% of average annual dose. Past average annual cabin crew dose can be modeled by exploiting systematic external influences as well as individual behavioral determinants of radiation exposure, thereby enabling future dose-response analyses of the full aircrew cohort including measurement error information.

Evaluation of Radiation Exposure to Staff and Environment Dose from [18F]-FDG in PET/CT and Cyclotron Center using Thermoluminescent Dosimetry

PubMed Central

Zargan, S.; Ghafarian, P.; Shabestani Monfared, A.; Sharafi, A.A.; Bakhshayeshkaram, M.; Ay, M.R.

2017-01-01

Background: PET/CT imaging using [18F]-FDG is utilized in clinical oncology for tumor detecting, staging and responding to therapy procedures. Essential consideration must be taken for radiation staff due to high gamma radiation in PET/CT and cyclotron center. The aim of this study was to assess the staff exposure regarding whole body and organ dose and to evaluate environment dose in PET/CT and cyclotron center. Materials and Methods: 80 patients participated in this study. Thermoluminescence, electronic personal dosimeter and Geiger-Muller dosimeter were also utilized for measurement purpose. Results: The mean annual equivalent organ dose for scanning operator with regard to lens of eyes, thyroid, breast and finger according to mean±SD value, were 0.262±0.044, 0.256±0.046, 0.257±0.040 and 0.316±0.118, respectively. The maximum and minimum estimated annual whole body doses were observed for injector and the chemist group with values of (3.98±0.021) mSv/yr and (1.64±0.014) mSv/yr, respectively. The observed dose rates were 5.67 µSv/h in uptake room at the distance of 0.5 meter from the patient whereas the value 4.94 and 3.08 µSv/h were recorded close to patient’s head in PET/CT room and 3.5 meter from the reception desk. Conclusion: In this study, the injector staff and scanning operator received the first high level and second high level of radiation. This study confirmed that low levels of radiation dose were received by all radiation staff during PET/CT procedure using 18F-FDG due to efficient shielding and using trained radiation staff in PET/CT and cyclotron center of Masih Daneshvari hospital. PMID:28451574

Public exposure due to external gamma background radiation in boundary areas of Iran.

PubMed

Pooya, S M Hosseini; Dashtipour, M R; Enferadi, A; Orouji, T

2015-09-01

A monitoring program in boundary areas of a country is an appropriate way to indicate the level of public exposure. In this research, gamma background radiation was measured using TL dosimeters at 12 boundary areas as well as in the capital city of Iran during the period 2010 to 2011. The measurements were carried out in semi-annual time intervals from January to June and July to December in each year. The maximum average dose equivalent value measured was approximately 70 μSv/month for Tehran city. Also, the average dose values obtained were less than 40 μSv/month for all the cities located at the sea level except that of high level natural radiation area of Ramsar, and more than 55 μSv/month for the higher elevation cities. The public exposure due to ambient gamma dose equivalent in Iran is within the levels reported by UNSCEAR. Copyright © 2015 Elsevier Ltd. All rights reserved.

Natural radioactivity investigation in Dam sediments of northeast Algeria using gamma spectroscopy

NASA Astrophysics Data System (ADS)

Benrachi, Fatima; Bouhila, Ghania; Saadi, Asma; Ramdhane, Mourad

2017-09-01

Current research paper intends to estimate the natural radioactivity levels in sediments samples collected from Beni Haroun Dam in the northeast Algeria, using high resolution HPGe detector. The mean activity concentrations values measured for the radionuclides 232Th, 226Ra and 40K are 18.9 ± 1.9, 37.3 ± 2.7 and 149.9 ± 5.5 Bq/kg, respectively. The 137Cs anthropogenic radionuclide has been observed with maximum activity concentration value of 0.8 ± 0.4 Bq/kg, which is considered an insignificant amount. In order to assess the radiological threat of gamma radiations emitted by these radionuclides on the health of the population, absorbed dose rate, annual effective dose equivalent and radiation hazard indices were had been calculated. The obtained values are compared with the world wide average ones.

Result Summary for the Area 5 Radioactive Waste Management Site Performance Assessment Model Version 4.110

DOE Office of Scientific and Technical Information (OSTI.GOV)

NSTec Environmental Management

2011-07-20

Results for Version 4.110 of the Area 5 Radioactive Waste Management Site (RWMS) performance assessment (PA) model are summarized. Version 4.110 includes the fiscal year (FY) 2010 inventory estimate, including a future inventory estimate. Version 4.110 was implemented in GoldSim 10.11(SP4). The following changes have been implemented since the last baseline model, Version 4.105: (1) Updated the inventory and disposal unit configurations with data through the end of FY 2010. (1) Implemented Federal Guidance Report 13 Supplemental CD dose conversion factors (U.S. Environmental Protection Agency, 1999). Version 4.110 PA results comply with air pathway and all-pathways annual total effective dosemore » (TED) performance objectives (Tables 2 and 3, Figures 1 and 2). Air pathways results decrease moderately for all scenarios. The time of the maximum for the air pathway open rangeland scenario shifts from 1,000 to 100 years (y). All-pathways annual TED increases for all scenarios except the resident scenario. The maximum member of public all-pathways dose occurs at 1,000 y for the resident farmer scenario. The resident farmer dose was predominantly due to technetium-99 (Tc-99) (82 percent) and lead-210 (Pb-210) (13 percent). Pb-210 present at 1,000 y is produced predominantly by radioactive decay of uranium-234 (U-234) present at the time of disposal. All results for the postdrilling and intruder-agriculture scenarios comply with the performance objectives (Tables 4 and 5, Figures 3 and 4). The postdrilling intruder results are similar to Version 4.105 results. The intruder-agriculture results are similar to Version 4.105, except for the Pit 6 Radium Disposal Unit (RaDU). The intruder-agriculture result for the Shallow Land Burial (SLB) disposal units is a significant fraction of the performance objective and exceeds the performance objective at the 95th percentile. The intruder-agriculture dose is due predominantly to Tc-99 (75 percent) and U-238 (9.5 percent). The acute intruder scenario results comply with all performance objectives (Tables 6 and 7, Figures 5 and 6). The acute construction result for the SLB disposal units decreases significantly with this version. The maximum acute intruder dose occurs at 1,000 y for the SLB disposal units under the acute construction scenario. The acute intruder dose is caused by multiple radionuclides including U-238 (31 percent), Th-229 (28 percent), plutonium-239 (8.6 percent), U-233 (7.8 percent), and U-234 (6.7 percent). All results for radon-222 (Rn-222) flux density comply with the performance objective (Table 8, Figure 7). The mean Pit 13 RaDU flux density is close to the 0.74 Bq m{sup -2} s{sup -1} limit.« less

[Personal dose monitoring of radiation workers in medical institutions at the municipal level and below in a city from 2011 to 2014].

PubMed

Wang, C; Mo, S F; Zhang, J B; Li, J R; Huang, R L; Tan, H Y

2017-08-20

Objective: To determine the personal dose level of radiation workers in medical institutions at the municipal level and below in a city, and to provide a scientific support for strengthening the radiation protection in the city's medical institutions. Methods: Information of the successful applicants for the "Radiation Worker Permit" from 174 medical institutions at the municipal level and below was collected from October 1, 2011 to December 31, 2014. The annual effective dose was calculated based on the personal dose monitoring report, and indicators including sex, permit application time, hospital level, type of occupational radiation, length of radiation work, blood test, and micronucleated lymphocyte rate were analyzed. Results: Of the 1 143 radiation worker permit applications submitted by medical institutions the municipal level and below in this city from 2011 to 2014, 1 123 provided at least one personal dose monitoring report. The annual effective dose of the radiation workers was 0-4.76 mSv (mean 0.31±0.40 mSv) , and the collective annual effective dose was 351.96 mSv. The annual effective dose was significantly different between radiation workers with different times of permit application, hospital levels, and types of occupational radiation ( P <0.05) . Interventional radiology workers had the highest annual effective dose (0.63 mSv) , and annual effective dose was significantly different between interventional radiology workers with different lengths of radiation work ( H =10.812, P <0.05) . Conclusion: The personal radiation dose of radiation workers in medical institutions at the municipal level and below in this city is maintained at a relatively low level, suggesting that the occupational environment is relatively safe for these workers. However, more focus should be placed on clinical interventional radiology workers.

Occupational Radiation Exposure to the Extremities of Medical Staff during Hysterosalpingography and Radionuclide Bone Scan Procedures in Several Nigerian Hospitals.

PubMed

Jibiri, Nnamdi Norbert; Akintunde, Tawakalitu Oluwatoyin; Dambele, Musa Yusuf; Olowookere, Christopher Jimoh

2016-10-05

The practice of regular dose measurement helps to ascertain the level of occupational dose delivered to the staff involved in diagnostic procedures. This study was carried out to evaluate the dose exposed to the hands of radiologists and a radiologic technologist carrying out HSG and radionuclide bone scan examinations in several hospitals in Nigeria. Radiation doses exposed to the hands of radiologists and a technician carrying out hysterosalpingography (HSG) and bone scan procedures were measured using calibrated thermo-luminescent dosimeters. Five radiologists and a radiologic technologist were included in the study for dose measurement. The study indicates that each radiologist carried out approximately 2 examinations per week with the mean dose ranging between 0.49-0.62 mSv per week, resulting in an annual dose of 191 mSv. Similarly, the occupational dose delivered to both the left and right hands of a radiologic technologist administering 99mTc-methylene diphosphonate (MDP) without cannula and with cannula were 10.68 (720.2) and 13.82 (556.4) mSv per week (and per annum), respectively. It was determined that the left hand of the personnel received higher doses than their right hand. The estimated annual dose during HSG is far below the annual dose limit for deterministic effects, however, it is greater than 10% of the applicable annual dose limit. Hence, routine monitoring is required to ensure adequate protection of the personnel. The total annual dose received during the bone scan exceeds the annual dose limit for both hands, and the dose to either left or right hand is greater than the dose limit of 500 mSv/yr. The radiologists monitored are not expected to incur any deterministic effects during HSG examinations, however, accumulated doses arising from the scattered radiation to the eyes, legs, and neck could be substantial and might lead to certain effects. More staff are required to administer 99mTc-MDP in Nigerian institutions to prevent excessive doses to personnel.

Occupational Radiation Exposure to the Extremities of Medical Staff during Hysterosalpingography and Radionuclide Bone Scan Procedures in Several Nigerian Hospitals

PubMed Central

Jibiri, Nnamdi Norbert; Akintunde, Tawakalitu Oluwatoyin; Dambele, Musa Yusuf; Olowookere, Christopher Jimoh

2016-01-01

Objective: The practice of regular dose measurement helps to ascertain the level of occupational dose delivered to the staff involved in diagnostic procedures. This study was carried out to evaluate the dose exposed to the hands of radiologists and a radiologic technologist carrying out HSG and radionuclide bone scan examinations in several hospitals in Nigeria. Methods: Radiation doses exposed to the hands of radiologists and a technician carrying out hysterosalpingography (HSG) and bone scan procedures were measured using calibrated thermo-luminescent dosimeters. Five radiologists and a radiologic technologist were included in the study for dose measurement. Results: The study indicates that each radiologist carried out approximately 2 examinations per week with the mean dose ranging between 0.49-0.62 mSv per week, resulting in an annual dose of 191 mSv. Similarly, the occupational dose delivered to both the left and right hands of a radiologic technologist administering 99mTc-methylene diphosphonate (MDP) without cannula and with cannula were 10.68 (720.2) and 13.82 (556.4) mSv per week (and per annum), respectively. It was determined that the left hand of the personnel received higher doses than their right hand. Conclusion: The estimated annual dose during HSG is far below the annual dose limit for deterministic effects, however, it is greater than 10% of the applicable annual dose limit. Hence, routine monitoring is required to ensure adequate protection of the personnel. The total annual dose received during the bone scan exceeds the annual dose limit for both hands, and the dose to either left or right hand is greater than the dose limit of 500 mSv/yr. The radiologists monitored are not expected to incur any deterministic effects during HSG examinations, however, accumulated doses arising from the scattered radiation to the eyes, legs, and neck could be substantial and might lead to certain effects. More staff are required to administer 99mTc-MDP in Nigerian institutions to prevent excessive doses to personnel. PMID:27751973

Analysis of trends in selected streamflow statistics for the Concho River Basin, Texas, 1916-2009

USGS Publications Warehouse

Barbie, Dana L.; Wehmeyer, Loren L.; May, Jayne E.

2012-01-01

Six U.S. Geological Survey streamflow-gaging stations were selected for analysis. Streamflow-gaging station 08128000 South Concho River at Christoval has downward trends for annual maximum daily discharge and annual instantaneous peak discharge for the combined period 1931-95, 2002-9. Streamflow-gaging station 08128400 Middle Concho River above Tankersley has downward trends for annual maximum daily discharge and annual instantaneous peak discharge for the combined period 1962-95, 2002-9. Streamflow-gaging station 08128500 Middle Concho River near Tankersley has no significant trends in the streamflow statistics considered for the period 1931-60. Streamflow-gaging station 08134000 North Concho River near Carlsbad has downward trends for annual mean daily discharge, annual 7-day minimum daily discharge, annual maximum daily discharge, and annual instantaneous peak discharge for the period 1925-2009. Streamflow-gaging stations 08136000 Concho River at San Angelo and 08136500 Concho River at Paint Rock have downward trends for 1916-2009 for all streamflow statistics calculated, but streamflow-gaging station 08136000 Concho River at San Angelo has an upward trend for annual maximum daily discharge during 1964-2009. The downward trends detected during 1916-2009 for the Concho River at San Angelo are not unexpected because of three reservoirs impounding and profoundly regulating streamflow.

Current ozone levels threaten gross primary production and yield of Mediterranean annual pastures and nitrogen modulates the response

NASA Astrophysics Data System (ADS)

Calvete-Sogo, Héctor; Elvira, Susana; Sanz, Javier; González-Fernández, Ignacio; García-Gómez, Héctor; Sánchez-Martín, Laura; Alonso, Rocío; Bermejo-Bermejo, Victoria

2014-10-01

Pastures are among the most important ecosystems in Europe considering their biodiversity and distribution area. However, their response to increasing tropospheric ozone (O3) and nitrogen (N) deposition, two of the main drivers of global change, is still uncertain. A new Open-Top Chamber (OTC) experiment was performed in central Spain, aiming to study annual pasture response to O3 and N in close to natural growing conditions. A mixture of six species of three representative families was sowed in the field. Plants were exposed for 40 days to four O3 treatments: filtered air, non-filtered air (NFA) reproducing ambient levels and NFA supplemented with 20 and 40 nl l-1 O3. Three N treatments were considered to reach the N integrated doses of “background”, +20 or +40 kg N ha-1. Ozone significantly reduced green and total aboveground biomass (maximum reduction 25%) and increased the senescent biomass (maximum increase 40%). Accordingly, O3 decreased community Gross Primary Production due to both a global reduction of ecosystem CO2 exchange and an increase of ecosystem respiration. Nitrogen could partially counterbalance O3 effects on aboveground biomass when the levels of O3 were moderate, but at the same time O3 exposure reduced the fertilization effect of higher N availability. Therefore, O3 must be considered as a stress factor for annual pastures in the Mediterranean areas.

Influence of image slice thickness on rectal dose-response relationships following radiotherapy of prostate cancer

NASA Astrophysics Data System (ADS)

Olsson, C.; Thor, M.; Liu, M.; Moissenko, V.; Petersen, S. E.; Høyer, M.; Apte, A.; Deasy, J. O.

2014-07-01

When pooling retrospective data from different cohorts, slice thicknesses of acquired computed tomography (CT) images used for treatment planning may vary between cohorts. It is, however, not known if varying slice thickness influences derived dose-response relationships. We investigated this for rectal bleeding using dose-volume histograms (DVHs) of the rectum and rectal wall for dose distributions superimposed on images with varying CT slice thicknesses. We used dose and endpoint data from two prostate cancer cohorts treated with three-dimensional conformal radiotherapy to either 74 Gy (N = 159) or 78 Gy (N = 159) at 2 Gy per fraction. The rectum was defined as the whole organ with content, and the morbidity cut-off was Grade ≥2 late rectal bleeding. Rectal walls were defined as 3 mm inner margins added to the rectum. DVHs for simulated slice thicknesses from 3 to 13 mm were compared to DVHs for the originally acquired slice thicknesses at 3 and 5 mm. Volumes, mean, and maximum doses were assessed from the DVHs, and generalized equivalent uniform dose (gEUD) values were calculated. For each organ and each of the simulated slice thicknesses, we performed predictive modeling of late rectal bleeding using the Lyman-Kutcher-Burman (LKB) model. For the most coarse slice thickness, rectal volumes increased (≤18%), whereas maximum and mean doses decreased (≤0.8 and ≤4.2 Gy, respectively). For all a values, the gEUD for the simulated DVHs were ≤1.9 Gy different than the gEUD for the original DVHs. The best-fitting LKB model parameter values with 95% CIs were consistent between all DVHs. In conclusion, we found that the investigated slice thickness variations had minimal impact on rectal dose-response estimations. From the perspective of predictive modeling, our results suggest that variations within 10 mm in slice thickness between cohorts are unlikely to be a limiting factor when pooling multi-institutional rectal dose data that include slice thickness variations within this range. Presented in part at the European Society for Therapeutic Radiotherapy and Oncology Annual Meeting, April 5-8, 2014, Vienna, Austria.

Radiation exposure from consumer products and miscellaneous sources

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1977-01-01

This review of the literature indicates that there is a variety of consumer products and miscellaneous sources of radiation that result in exposure to the U.S. population. A summary of the number of people exposed to each such source, an estimate of the resulting dose equivalents to the exposed population, and an estimate of the average annual population dose equivalent are tabulated. A review of the data in this table shows that the total average annual contribution to the whole-body dose equivalent of the U.S. population from consumer products is less than 5 mrem; about 70 percent of this arisesmore » from the presence of naturally-occurring radionuclides in building materials. Some of the consumer product sources contribute exposure mainly to localized tissues or organs. Such localized estimates include: 0.5 to 1 mrem to the average annual population lung dose equivalent (generalized); 2 rem to the average annual population bronchial epithelial dose equivalent (localized); and 10 to 15 rem to the average annual population basal mucosal dose equivalent (basal mucosa of the gum). Based on these estimates, these sources may be grouped or classified as those that involve many people and the dose equivalent is relative large or those that involve many people but the dose equivalent is relatively small, or the dose equivalent is relatively large but the number of people involved is small.« less

7 CFR 4280.126 - Guarantee/annual renewal fee percentages.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 7 Agriculture 15 2010-01-01 2010-01-01 false Guarantee/annual renewal fee percentages. 4280.126... renewal fee percentages. (a) Fee ceilings. The maximum guarantee fee that may be charged is 1 percent. The maximum annual renewal fee that may be charged is 0.5 percent. The Agency will establish each year the...

Risk assessment during transport of radioactive materials through the Suez Canal

NASA Astrophysics Data System (ADS)

Sabek, M. G.; El-Shinawy, R. M. K.; Gomaa, M.

1997-03-01

In this paper a study for risk assessment of the impact of transporting radioactive materials, during the period 1986-1992, through the Suez Canal of Egypt is given. The code RADTRAN-IV was used for this study. The results of the code, for a normal case, show that the transportation of low activity materials such as uranium (U 3O 8) represent the main items that contribute significantly to the collective dose within the Suez Canal area (Port-Said, Ismailia and Suez). The values of the annual collective dose due to transportation of all radionuclide materials was found to be at a maximum in Suez town and is equal to 5.04 × 10 -8 Man-Sv for the whole populations. If we only consider the workder at the harbour (estimated to be 50 persons), the value of the annual collective dose is about 3.33 × 10 -4 Man-Sv. These values are less than the exemption value of 1 Man-Sv recommended by the IAEA. For the accident case, the following pathways are considered by the code: ground-shine, direct inhalation, inhalation of resuspended material and cloud-shine. The total values of the estimated risks for each radionuclide material are presented in table form and, in addition, health effects (genetic effects, GE, and latent cancer fatality), LCF) are discussed. The calculated values of the radiological risks are very low for the three towns, showing that no radiation-induced early deaths are to be expected.

Temporal Lobe Reactions After Radiotherapy With Carbon Ions: Incidence and Estimation of the Relative Biological Effectiveness by the Local Effect Model

DOE Office of Scientific and Technical Information (OSTI.GOV)

Schlampp, Ingmar; Karger, Christian P.; Jaekel, Oliver

2011-07-01

Purpose: To identify predictors for the development of temporal lobe reactions (TLR) after carbon ion radiation therapy (RT) for radiation-resistant tumors in the central nervous system and to evaluate the predictions of the local effect model (LEM) used for calculation of the biologically effective dose. Methods and Materials: This retrospective study reports the TLR rates in patients with skull base chordomas and chondrosarcomas irradiated with carbon ions at GSI, Darmstadt, Germany, in the years 2002 and 2003. Calculation of the relative biological effectiveness and dose optimization of treatment plans were performed on the basis of the LEM. Clinical examinations andmore » magnetic resonance imaging (MRI) were performed at 3, 6, and 12 months after RT and annually thereafter. Local contrast medium enhancement in temporal lobes, as detected on MRI, was regarded as radiation-induced TLR. Dose-volume histograms of 118 temporal lobes in 59 patients were analyzed, and 16 therapy-associated and 2 patient-associated factors were statistically evaluated for their predictive value for the occurrence of TLR. Results: Median follow-up was 2.5 years (range, 0.3--6.6 years). Age and maximum dose applied to at least 1 cm{sup 3} of the temporal lobe (D{sub max,V-1cm}3, maximum dose in the remaining temporal lobe volume, excluding the volume 1 cm{sup 3} with the highest dose) were found to be the most important predictors for TLR. Dose response curves of D{sub max,V-1cm}3 were calculated. The biologically equivalent tolerance doses for the 5% and 50% probabilities to develop TLR were 68.8 {+-} 3.3 Gy equivalents (GyE) and 87.3 {+-} 2.8 GyE, respectively. Conclusions: D{sub max,V-1cm}3 is predictive for radiation-induced TLR. The tolerance doses obtained seem to be consistent with published data for highly conformal photon and proton irradiations. We could not detect any clinically relevant deviations between clinical findings and expectations based on predictions of the LEM.« less

Radiation protection for human missions to the Moon and Mars

NASA Technical Reports Server (NTRS)

Simonsen, Lisa C.; Nealy, John E.

1991-01-01

Radiation protection assessments are performed for advanced Lunar and Mars manned missions. The Langley cosmic ray transport code and the nucleon transport code are used to quantify the transport and attenuation of galactic cosmic rays and solar proton flares through various shielding media. Galactic cosmic radiation at solar maximum and minimum, as well as various flare scenarios are considered. Propagation data for water, aluminum, liquid hydrogen, lithium hydride, lead, and lunar and Martian regolith (soil) are included. Shield thickness and shield mass estimates required to maintain incurred doses below 30 day and annual limits (as set for Space Station Freedom and used as a guide for space exploration) are determined for simple geometry transfer vehicles. On the surface of Mars, dose estimates are presented for crews with their only protection being the carbon dioxide atmosphere and for crews protected by shielding provided by Martian regolith for a candidate habitat.

Kara Sea radioactivity assessment.

PubMed

Osvath, I; Povinec, P P; Baxter, M S

1999-09-30

Investigations following five international expeditions to the Kara Sea have shown that no radiologically significant contamination has occurred outside of the dumping sites in Novaya Zemlya bays. Increased levels of radionuclides in sediment have only been observed in Abrosimov and Stepovoy Bays very close to dumped containers. Evaluations of radionuclide inventories in water and sediment of the open Kara Sea and Novaya Zemlya bays as well as soil from the shore of Abrosimov bay have shown that radionuclide contamination of the open Kara Sea is mainly due to global fallout, with smaller contributions from the Sellafield reprocessing plant, the Chernobyl accident run-off from the Ob and Yenisey rivers and local fallout. Computer modelling results have shown that maximum annual doses of approximately 1 mSv are expected for a hypothetical critical group subsisting on fish caught in the Novaya Zemlya bays whereas populations living on the mainland can be expected to receive doses at least three orders of magnitude lower.

Occupational exposures in two industrial plants devoted to the production of ammonium phosphate fertilisers.

PubMed

Bolívar, J P; García-Tenorio, R; Mosqueda, F; Gázquez, M J; López-Coto, I; Adame, J A; Vaca, F

2013-03-01

In order to fill a gap in the open literature, occupational exposures and activity concentrations have been assessed in two NORM industrial plants, located in the south-west of Spain, devoted to the production of mono-ammonium phosphate (MAP) and di-ammonium phosphate (DAP) fertilisers. The annual effective doses received by the workers from these plants are clearly below 1 mSv yr(-1) and the contribution due to external radiation is similar to that due to inhalation. The contribution to the maximum effective doses due to inhalation of particulate matter has been estimated to be about 0.12 mSv yr(-1), while the (222)Rn concentrations inside the plants are of no concern. Consequently, no additional actions or radiological protection measures need to be taken to decrease the natural radiation received by the workers in these facilities.

Dose estimation and dating of pottery from Turkey

NASA Astrophysics Data System (ADS)

Altay Atlıhan, M.; Şahiner, Eren; Soykal Alanyalı, Feriştah

2012-06-01

The luminescence method is a widely used technique for environmental dosimetry and dating archaeological, geological materials. In this study, equivalent dose (ED) and annual dose rate (AD) of an archaeological sample were measured. The age of the material was calculated by means of equivalent dose divided by the annual dose rate. The archaeological sample was taken from Antalya, Turkey. Samples were prepared by the fine grain technique and equivalent dose was found using multiple-aliquot-additive-dose (MAAD) and single aliquot regeneration (SAR) techniques. Also the short shine normalization-MAAD and long shine normalization-MAAD were applied and the results of the methods were compared with each other. The optimal preheat temperature was found to be 200 °C for 10 min. The annual doses of concentrations of the major radioactive isotopes were determined using a high-purity germanium detector and a low-level alpha counter. The age of the sample was found to be 510±40 years.

Annual limits on intake (ALI) values in ICRP 61 and 10 CFR Part 20 (1991)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhu, M.; Kearfott, K.J.

The newest major revision of Nuclear Regulatory Commission`s 10 CFR Part 20 (1991) incorporates the new dose methodology system, revised limits, and improved internal dose computations presented in International Commission on Radiation Protection (ICRP) Publication 30 (1979). A year before the issue of this revised 10 CFR Part 20, the ICRP dispatched Publication 61 (1990). This new ICRP report employed different dose limits, in addition to incorporating more recent biological information and variations in physiological and different tissue weighing factors for various organs. An investigation of the numerical differences in the Annual Limit on Intake (ALI) reported in this moremore » recent international regulations and those of the new regulations was thus undertaken. Overall means, medians, modes, maximum, minimum, and ranges of the percent changes are almost identical for ingestion and inhalation, although the percent difference between 10 CFR and ICRP Publication 61 showed minor differences for individual radionuclides. Approximately 334 of 1,351 radionuclides for inhalation and 173 of 771 radionuclides for ingestion have much less restrictive ALIs in the new ICRP recommendations than in the old, with some of those limits increased by at least a factor of two. Approximately 51% of the radionuclides for ingestion intake and 48% of radionuclides for inhalation intake showed changes of greater than 25%. The radionuclides observed to have much less restrictive ALIs are primarily the radionuclides of thorium, mercury, plutonium, uranium, and americium which have short effective clearance rates. While many countries have already applied the ICRP 61 recommendations to their radiation protection standards, using the ICRP 30 recommendation in the United States does not match the international standards even when the values of the ALIs are adjusted for differences in dose limits.« less

MPC and ALI: their basis and their comparison

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kennedy, W.E. Jr.; Watson, E.C.

Radiation protection regulations in the United States have evolved from the recommendations of the International Commission on Radiological Protection (ICRP) and the National Council on Radiation Protection and Measurements (NCRP). In 1959, the ICRP issued Publication 2 which contained specific recommendations on dose rate limits, permissible body burdens, metabolic data for radionuclides, and maximum permissible concentrations (MPC) in air or water. Over the next 20 years, new information became available concerning the effects of radiation, the uptake and retention of radionuclides, and the radioactive decay schemes of parent radionuclides. To include this newer information, the ICRP issued Publication 30 inmore » 1978 to supersede Publication 2. One of the secondary limits defined in Publication 30 is the annual limit of intake (ALI). Radionuclide specific ALI values are intended to replace MPC values in determining whether or not ambient air and water concentrations are sufficiently low to maintain the dose to workers within accepted dose rate limits. In this paper, we discuss the derivation of MPC and ALI values, compare inhalation committed dose equivalent factors derived from ICRP Publications 2 and 30, and discuss the practical implications of using either MPC or ALI in determining compliance with occupational exposure limits. 6 references.« less

Comparison of 2D and 3D Imaging and Treatment Planning for Postoperative Vaginal Apex High-Dose Rate Brachytherapy for Endometrial Cancer

DOE Office of Scientific and Technical Information (OSTI.GOV)

Russo, James K.; Armeson, Kent E.; Richardson, Susan, E-mail: srichardson@radonc.wustl.edu

2012-05-01

Purpose: To evaluate bladder and rectal doses using two-dimensional (2D) and 3D treatment planning for vaginal cuff high-dose rate (HDR) in endometrial cancer. Methods and Materials: Ninety-one consecutive patients treated between 2000 and 2007 were evaluated. Seventy-one and 20 patients underwent 2D and 3D planning, respectively. Each patient received six fractions prescribed at 0.5 cm to the superior 3 cm of the vagina. International Commission on Radiation Units and Measurements (ICRU) doses were calculated for 2D patients. Maximum and 2-cc doses were calculated for 3D patients. Organ doses were normalized to prescription dose. Results: Bladder maximum doses were 178% ofmore » ICRU doses (p < 0.0001). Two-cubic centimeter doses were no different than ICRU doses (p = 0.22). Two-cubic centimeter doses were 59% of maximum doses (p < 0.0001). Rectal maximum doses were 137% of ICRU doses (p < 0.0001). Two-cubic centimeter doses were 87% of ICRU doses (p < 0.0001). Two-cubic centimeter doses were 64% of maximum doses (p < 0.0001). Using the first 1, 2, 3, 4 or 5 fractions, we predicted the final bladder dose to within 10% for 44%, 59%, 83%, 82%, and 89% of patients by using the ICRU dose, and for 45%, 55%, 80%, 85%, and 85% of patients by using the maximum dose, and for 37%, 68%, 79%, 79%, and 84% of patients by using the 2-cc dose. Using the first 1, 2, 3, 4 or 5 fractions, we predicted the final rectal dose to within 10% for 100%, 100%, 100%, 100%, and 100% of patients by using the ICRU dose, and for 60%, 65%, 70%, 75%, and 75% of patients by using the maximum dose, and for 68%, 95%, 84%, 84%, and 84% of patients by using the 2-cc dose. Conclusions: Doses to organs at risk vary depending on the calculation method. In some cases, final dose accuracy appears to plateau after the third fraction, indicating that simulation and planning may not be necessary in all fractions. A clinically relevant level of accuracy should be determined and further research conducted to address this issue.« less

Flood frequency analysis for nonstationary annual peak records in an urban drainage basin

USGS Publications Warehouse

Villarini, G.; Smith, J.A.; Serinaldi, F.; Bales, J.; Bates, P.D.; Krajewski, W.F.

2009-01-01

Flood frequency analysis in urban watersheds is complicated by nonstationarities of annual peak records associated with land use change and evolving urban stormwater infrastructure. In this study, a framework for flood frequency analysis is developed based on the Generalized Additive Models for Location, Scale and Shape parameters (GAMLSS), a tool for modeling time series under nonstationary conditions. GAMLSS is applied to annual maximum peak discharge records for Little Sugar Creek, a highly urbanized watershed which drains the urban core of Charlotte, North Carolina. It is shown that GAMLSS is able to describe the variability in the mean and variance of the annual maximum peak discharge by modeling the parameters of the selected parametric distribution as a smooth function of time via cubic splines. Flood frequency analyses for Little Sugar Creek (at a drainage area of 110 km2) show that the maximum flow with a 0.01-annual probability (corresponding to 100-year flood peak under stationary conditions) over the 83-year record has ranged from a minimum unit discharge of 2.1 m3 s- 1 km- 2 to a maximum of 5.1 m3 s- 1 km- 2. An alternative characterization can be made by examining the estimated return interval of the peak discharge that would have an annual exceedance probability of 0.01 under the assumption of stationarity (3.2 m3 s- 1 km- 2). Under nonstationary conditions, alternative definitions of return period should be adapted. Under the GAMLSS model, the return interval of an annual peak discharge of 3.2 m3 s- 1 km- 2 ranges from a maximum value of more than 5000 years in 1957 to a minimum value of almost 8 years for the present time (2007). The GAMLSS framework is also used to examine the links between population trends and flood frequency, as well as trends in annual maximum rainfall. These analyses are used to examine evolving flood frequency over future decades. ?? 2009 Elsevier Ltd.

SU-F-T-113: Inherent Functional Dependence of Spinal Cord Doses of Variable Irradiated Volumes in Spine SBRT

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ma, L; Braunstein, S; Chiu, J

2016-06-15

Purpose: Spinal cord tolerance for SBRT has been recommended for the maximum point dose level or at irradiated volumes such as 0.35 mL or 10% of contoured volumes. In this study, we investigated an inherent functional relationship that associates these dose surrogates for irradiated spinal cord volumes of up to 3.0 mL. Methods: A hidden variable termed as Effective Dose Radius (EDR) was formulated based on a dose fall-off model to correlate dose at irradiated spinal cord volumes ranging from 0 mL (point maximum) to 3.0 mL. A cohort of 15 spine SBRT cases was randomly selected to derive anmore » EDR-parameterized formula. The mean prescription dose for the studied cases was 21.0±8.0 Gy (range, 10–40Gy) delivered in 3±1 fractions with target volumes of 39.1 ± 70.6 mL. Linear regression and variance analysis were performed for the fitting parameters of variable EDR values. Results: No direct correlation was found between the dose at maximum point and doses at variable spinal cord volumes. For example, Pearson R{sup 2} = 0.643 and R{sup 2}= 0.491 were obtained when correlating the point maximum dose with the spinal cord dose at 1 mL and 3 mL, respectively. However, near perfect correlation (R{sup 2} ≥0.99) was obtained when corresponding parameterized EDRs. Specifically, Pearson R{sup 2}= 0.996 and R{sup 2} = 0.990 were obtained when correlating EDR (maximum point dose) with EDR (dose at 1 mL) and EDR(dose at 3 mL), respectively. As a result, high confidence level look-up tables were established to correlate spinal cord doses at the maximum point to any finite irradiated volumes. Conclusion: An inherent functional relationship was demonstrated for spine SBRT. Such a relationship unifies dose surrogates at variable cord volumes and proves that a single dose surrogate (e.g. point maximum dose) is mathematically sufficient in constraining the overall spinal cord dose tolerance for SBRT.« less

Cosmic Radiation Exposure of Future Hypersonic Flight Missions.

PubMed

Koops, L

2017-06-15

Cosmic radiation exposure in air traffic grows with flight altitude, geographical latitude and flight time. For future high-speed intercontinental point-to-point travel, the trade-off between reduced flight time and enhanced dose rate at higher flight altitudes is investigated. Various representative (partly) hypersonic cruise missions are considered and in dependence on solar activity the integral route dose is calculated for envisaged flight profiles and trajectories. Our results are compared to those for corresponding air connections served by present day subsonic airliners. During solar maximum, we find a significant reduction in route dose for all considered high-speed missions compared to the subsonic reference. However, during solar minimum, comparable or somewhat larger doses result on transpolar trajectories with (partly) hypersonic cruise at Mach 5. Both solar activity and routing are hence found to determine, whether passengers can profit from shorter flight times in terms of radiation exposure, despite of altitude-induced higher dose rates. Yet, aircrews with fixed number of block hours are always subject to larger annual doses, which in the considered cases take values up to five times the reference. We comment on the implications of our results for route planning and aviation decision-making in the absence of radiation shielding solutions. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Annual, semi-annual and ter-annual variations of gravity wave momentum flux in 13 years of SABER data

NASA Astrophysics Data System (ADS)

Chen, Dan; Preusse, Peter; Ern, Manfred; Strube, Cornelia

2017-04-01

In this study, the variations at different time scales such as the annual cycle, the semiannual oscillation (SAO), the ter-annual cycle (about four monthly) and the quasi-biennial oscillation (QBO) in zonal mean GW amplitudes and GW momentum flux (GWMF) have been investigated using satellite observations from 2002-2014 and combining ECMWF high resolution data with the GORGRAT model. The global distribution (patterns) of spectral amplitudes of GW momentum flux in stratosphere and mesosphere (from 30 km to 90 km) show that the annual cycle is the most predominant variation, and then are SAO, ter-annual cycle and QBO. For annual components, two relatively isolated amplitude maxima appear in each hemisphere: a subtropical maximum is associated with convective sources in summer, a mid and high latitude maximum is associated with the polar vortex in winter. In the subtropics, GWs propagate upward obliquely to the higher latitudes. The winter maximum in the southern hemisphere has larger momentum flux than that one in the northern hemisphere. While on the SH the phase (i.e. time corresponding to the maximum GWMF) continuously descends with the maximum in July in the upper mesosphere and in September in the lower stratosphere, on the northern hemisphere, the phase has no visible altitude dependence with a maximum in December. For semiannual variations, in the MLT (70-80 km) region, there is an obvious enhancement of spectral amplitude at equatorial latitudes which relate to the dissipation of convectively forced GWs. The SAO in absolute momentum flux and the annual cycle in zonal momentum flux indicated that the variations at mid-latitudes (about from 30°-40°) are not a SAO signals but rather an annual cycle when the direction of GWMF is considered. The ter-annual cycle may be related to the duration of active convection in subtropical latitudes (from June to Sep. in north hemisphere) Indications for QBO are found latitude extension to mid-latitudes in stratosphere of both hemispheres and equatorial mesopause. Using these four dominant components of time scales and performing sinusoidal fits of GWMF we find that the patterns also at high latitudes are consistent with the range of 50°S to 50°N continuously covered by SABER.

Assessment of extended-release opioid analgesics for the treatment of chronic pain.

PubMed

Gudin, Jeffrey A

2013-03-01

Approximately 3.8 million patients annually receive extended-release (ER) or long-acting opioid prescriptions in the outpatient setting, around half of which are written by primary care physicians. Compared with short-acting, immediate-release (IR) formulations, ER and oral long-acting opioid analgesics are associated with clinical advantages, such as extended periods of time during which drug plasma levels are within the therapeutic range, decreased peak-to-trough fluctuations, and prolonged analgesia over the dosing period. Additionally, ER opioids offer a more convenient, less frequent dosing regimen to chronic pain patients who are often taking several concomitant medications. The increased utilization of ER opioids has been accompanied by a rise in the misuse and abuse of these formulations. Certain pharmacokinetic parameters (e.g., longer time to maximum drug plasma concentration, lower maximum drug plasma concentration) may decrease the abuse potential of intact ER opioids by limiting the positive subjective and reinforcing effects relative to IR formulations. Putative abuse-deterrent formulations have also recently been introduced to impede physical manipulation of these formulations, or reduce the harm resulting from such behavior. Such formulations may represent an incremental advance to reduce non-oral forms of abuse. This article reviews the pharmacokinetic profiles and abuse-deterrent features of newer ER opioid analgesics for the treatment of moderate to severe chronic pain.

Special Analysis for the Disposal of the Sandia National Laboratory Classified Macroencapsulated Mixed Waste at the Area 5 Radioactive Waste Management Site, Nevada National Security Site, Nye County, Nevada

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gregory, Louis B.

This special analysis evaluates whether the Sandia National Laboratory (SNL) Classified Macroencapsulated Mixed Waste stream (ASLA000001007, Revision 4) is suitable for disposal by shallow land burial (SLB) at the Area 5 Radioactive Waste Management Site (RWMS) at the Nevada National Security Site (NNSS). The SNL Classified Macroencapsulated Mixed Waste stream consists of debris from classified nuclear weapons components (SNL 2015). The SNL Classified Macroencapsulated Mixed Waste stream required a special analysis due to tritium (3H) exceeding the NNSS Waste Acceptance Criteria (WAC) Action Levels (U.S. Department of Energy, National Nuclear Security Administration Nevada Field Office [NNSA/NFO] 2015). The SNL Classifiedmore » Macroencapsulated Mixed Waste stream had no significant effect on the maximum mean and 95th percentile results for the resident air pathway and all-pathways annual total effective dose (TED). The SNL Classified Macroencapsulated Mixed Waste stream increases the mean air pathway and all-pathways annual TED from approximately 100 to 200 years after closure. Addition of the SNL Classified Macroencapsulated Mixed Waste stream inventory shifts the maximum TED to approximately 100 years after closure and increases the TED for several alternative exposure scenarios. The maximum mean and the 95th percentile 222Rn flux density remain less than the performance objective throughout the compliance period. The SNL Classified Macroencapsulated Mixed Waste stream is suitable for disposal by SLB at the Area 5 RWMS. The waste stream is recommended for approval without conditions.« less

Application of the ELDO approach to assess cumulative eye lens doses for interventional cardiologists.

PubMed

Farah, J; Struelens, L; Auvinen, A; Jacob, S; Koukorava, C; Schnelzer, M; Vanhavere, F; Clairand, I

2015-04-01

In preparation of a large European epidemiological study on the relation between eye lens dose and the occurrence of lens opacities, the European ELDO project focused on the development of practical methods to estimate retrospectively cumulative eye lens dose for interventional medical professionals exposed to radiation. The present paper applies one of the ELDO approaches, correlating eye lens dose to whole-body doses, to assess cumulative eye lens dose for 14 different Finnish interventional cardiologists for whom annual whole-body dose records were available for their entire working period. The estimated cumulative left and right eye lens dose ranged from 8 to 264 mSv and 6 to 225 mSv, respectively. In addition, calculations showed annual eye lens doses sometimes exceeding the new ICRP annual limit of 20 mSv. The work also highlights the large uncertainties associated with the application of such an approach proving the need for dedicated dosimetry systems in the routine monitoring of the eye lens dose. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

AN ESTIMATION OF THE EXPOSURE OF THE POPULATION OF ISRAEL TO NATURAL SOURCES OF IONIZING RADIATION.

PubMed

Epstein, L; Koch, J; Riemer, T; Haquin, G; Orion, I

2017-11-01

The radiation dose to the population of Israel due to exposure to natural sources of ionizing radiation was assessed. The main contributor to the dose is radon that accounts for 60% of the exposure to natural sources. The dose due to radon inhalation was assessed by combining the results of a radon survey in single-family houses with the results of a survey in apartments in multi-storey buildings. The average annual dose due to radon inhalation was found to be 1.2 mSv. The dose rate due to exposure to cosmic radiation was assessed using a code that calculates the dose rate at different heights above sea level, taking into account the solar cycle. The annual dose was calculated based on the fraction of time spent indoors and the attenuation provided by buildings and was found to be 0.2 mSv. The annual dose due to external exposure to the terrestrial radionuclides was similarly assessed. The indoor dose rate was calculated using a model that takes into account the concentrations of the natural radionuclides in building materials, the density and the thickness of the walls. The dose rate outdoors was calculated based on the concentrations of the natural radionuclides in different geological units in Israel as measured in an aerial survey and measurements above ground. The annual dose was found to be 0.2 mSv. Doses due to internal exposure other than exposure to radon were also calculated and were found to be 0.4 mSv. The overall annual exposure of the population of Israel to natural sources of ionizing radiation is therefore 2 mSv and ranges between 1.7 and 2.7 mSv. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

STUDY OF RADIATION EXPOSURE DUE TO RADON, THORON AND PROGENY IN THE INDOOR ENVIRONMENT OF YAMUNA AND TONS VALLEYS OF GARHWAL HIMALAYA.

PubMed

Prasad, Mukesh; Rawat, Mukesh; Dangwal, Anoop; Prasad, Ganesh; Mishra, Rosaline; Ramola, R C

2016-10-01

Long-term measurements of indoor radon, thoron and their progeny concentrations have been carried out in dwellings of Yamuna and Tons Valleys of Uttarkashi, Garhwal Himalaya to investigate the health risk associated with inhalation of radon, thoron and progeny. The experimentally determined values of radon, thoron and progeny concentrations were used to estimate the annual inhalation doses and annual effective doses. The annual inhalation dose has been found to vary from 0.8 to 3.9 mSv y -1 with an average of 1.8 mSv y -1 The annual effective dose from the exposure to radon and its progeny in the study area has been found to vary from 0.1 to 2.4 mSv with an average of 1.2±0.6 mSv. Similarly, the annual effective dose due to thoron and its progeny has been found to vary from 0.2 to 1.5 mSv with an average of 0.6±0.4. The measurement techniques and results obtained are discussed in detail. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Maximum dose rate is a determinant of hypothyroidism after 131I therapy of Graves' disease but the total thyroid absorbed dose is not.

PubMed

Krohn, Thomas; Hänscheid, Heribert; Müller, Berthold; Behrendt, Florian F; Heinzel, Alexander; Mottaghy, Felix M; Verburg, Frederik A

2014-11-01

The determinants of successful (131)I therapy of Graves' disease (GD) are unclear. To relate dosimetry parameters to outcome of therapy to identify significant determinants eu- and/or hypothyroidism after (131)I therapy in patients with GD. A retrospective study in which 206 Patients with GD treated in University Hospital between November 1999 and January 2011. All received (131)I therapy aiming at a total absorbed dose to the thyroid of 250 Gy based on pre-therapeutic dosimetry. Post-therapy dosimetric thyroid measurements were performed twice daily until discharge. From these measurements, thyroid (131)I half-life, the total thyroid absorbed dose, and the maximum dose rate after (131)I administration were calculated. In all, 48.5% of patients were hypothyroid and 28.6% of patients were euthyroid after (131)I therapy. In univariate analysis, nonhyperthyroid and hyperthyroid patients only differed by sex. A lower thyroid mass, a higher activity per gram thyroid tissue, a shorter effective thyroidal (131)I half-life, and a higher maximum dose rate, but not the total thyroid absorbed dose, were significantly associated with hypothyroidism. In multivariate analysis, the maximum dose rate remained the only significant determinant of hypothyroidism (P < .001). Maximum dose rates of 2.2 Gy/h and higher were associated with a 100% hypothyroidism rate. Not the total thyroid absorbed dose, but the maximum dose rate is a determinant of successfully achieving hypothyroidism in Graves' disease. Dosimetric concepts aiming at a specific total thyroid absorbed dose will therefore require reconsideration if our data are confirmed prospectively.

Occupational radiation exposure in vascular interventional radiology: A complete evaluation of different body regions.

PubMed

Bacchim Neto, Fernando Antonio; Alves, Allan Felipe Fattori; Mascarenhas, Yvone Maria; Nicolucci, Patrícia; Pina, Diana Rodrigues de

2016-08-01

To perform a complete evaluation on radiation doses, received by primary and assistant medical staff, while performing different vascular interventional radiology procedures. We evaluated dose received in different body regions during three categories of vascular procedures: lower limb angiography (Angiography), lower limb percutaneous transluminal angioplasty (Angioplasty) and stent graft placement for abdominal aortic aneurysm treatment (A. A. A. Treatment). We positioned the dosimeters near the eye lens, thyroid, chest, abdomen, hands, and feet of the interventional physicians. Equivalent dose was compared with annual dose limits for workers in order to determine the maximum number of procedures per year that each physician could perform. We assessed 90 procedures. We found the highest equivalent doses in the A. A. A. Treatment, in which 90% of the evaluations indicated at least one region receiving more than 1mSv per procedure. Angioplasty was the only procedural modality that provided statistically different doses for different professionals, which is an important aspect on regards to radiological protection strategies. In comparison with the dose limits, the most critical region in all procedures was the eye lens. Since each body region of the interventionist is exposed to different radiation levels, dose distribution measurements are essential for radiological protection strategies. These results indicate that dosimeters placed in abdomen instead of chest may represent more accurately the whole body doses received by the medical staff. Additional dosimeters and a stationary shield for the eye lens are strongly recommended. Copyright © 2016 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.

EVALUATION OF PROMPT DOSE ENVIRONMENT IN THE NATIONAL IGNITION FACILITY DURING D-D AND THD SHOTS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Khater, H; Dauffy, L; Sitaraman, S

2009-04-28

Evaluation of the prompt dose environment expected in the National Ignition Facility (NIF) during Deuterium-Deuterium (D-D) and Tritium-Hydrogen-Deuterium (THD) shots have been completed. D-D shots resulting in the production of an annual fusion yield of up to 2.4 kJ (200 shots with 10{sup 13} neutrons per shot) are considered. During the THD shot campaign, shots generating a total of 2 x 10{sup 14} neutrons per shot are also planned. Monte Carlo simulations have been performed to estimate prompt dose values inside the facility as well as at different locations outside the facility shield walls. The Target Chamber shielding, along withmore » Target Bay and Switchyard walls, roofs, and shield doors (when needed) will reduce dose levels in occupied areas to acceptable values during these shot campaigns. The calculated dose values inside occupied areas are small, estimated at 25 and 85 {micro}rem per shot during the D-D and THD shots, respectively. Dose values outside the facility are insignificant. The nearest building to the NIF facility where co-located workers may reside is at a distance of about 100 m from the Target Chamber Center (TCC). The dose in such a building is estimated at a fraction of a ?rem during a D-D or a THD shot. Dose at the nearest site boundary location (350 m from TCC), is caused by skyshine and to a lesser extent by direct radiation. The maximum off-site dose during any of the shots considered is less than 10 nano rem.« less

Radiation dose to physicians’ eye lens during interventional radiology

NASA Astrophysics Data System (ADS)

Bahruddin, N. A.; Hashim, S.; Karim, M. K. A.; Sabarudin, A.; Ang, W. C.; Salehhon, N.; Bakar, K. A.

2016-03-01

The demand of interventional radiology has increased, leading to significant risk of radiation where eye lens dose assessment becomes a major concern. In this study, we investigate physicians' eye lens doses during interventional procedures. Measurement were made using TLD-100 (LiF: Mg, Ti) dosimeters and was recorded in equivalent dose at a depth of 0.07 mm, Hp(0.07). Annual Hp(0.07) and annual effective dose were estimated using workload estimation for a year and Von Boetticher algorithm. Our results showed the mean Hp(0.07) dose of 0.33 mSv and 0.20 mSv for left and right eye lens respectively. The highest estimated annual eye lens dose was 29.33 mSv per year, recorded on left eye lens during fistulogram procedure. Five physicians had exceeded 20 mSv dose limit as recommended by international commission of radiological protection (ICRP). It is suggested that frequent training and education on occupational radiation exposure are necessary to increase knowledge and awareness of the physicians’ thus reducing dose during the interventional procedure.

40 CFR Appendix B to Part 191 - Calculation of Annual Committed Effective Dose

Code of Federal Regulations, 2013 CFR

2013-07-01

... the proportion of the stochastic risk resulting from irradiation of the tissue or organ to the total... of HE. III. Annual Committed Tissue or Organ Equivalent Dose For internal irradiation from...

40 CFR Appendix B to Part 191 - Calculation of Annual Committed Effective Dose

Code of Federal Regulations, 2012 CFR

2012-07-01

... the proportion of the stochastic risk resulting from irradiation of the tissue or organ to the total... of HE. III. Annual Committed Tissue or Organ Equivalent Dose For internal irradiation from...

40 CFR Appendix B to Part 191 - Calculation of Annual Committed Effective Dose

Code of Federal Regulations, 2014 CFR

2014-07-01

... the proportion of the stochastic risk resulting from irradiation of the tissue or organ to the total... of HE. III. Annual Committed Tissue or Organ Equivalent Dose For internal irradiation from...

40 CFR Appendix B to Part 191 - Calculation of Annual Committed Effective Dose

Code of Federal Regulations, 2010 CFR

2010-07-01

... the proportion of the stochastic risk resulting from irradiation of the tissue or organ to the total... of HE. III. Annual Committed Tissue or Organ Equivalent Dose For internal irradiation from...

40 CFR Appendix B to Part 191 - Calculation of Annual Committed Effective Dose

Code of Federal Regulations, 2011 CFR

2011-07-01

... the proportion of the stochastic risk resulting from irradiation of the tissue or organ to the total... of HE. III. Annual Committed Tissue or Organ Equivalent Dose For internal irradiation from...

Optimizing drug-dose alerts using commercial software throughout an integrated health care system.

PubMed

Saiyed, Salim M; Greco, Peter J; Fernandes, Glenn; Kaelber, David C

2017-11-01

All default electronic health record and drug reference database vendor drug-dose alerting recommendations (single dose, daily dose, dose frequency, and dose duration) were silently turned on in inpatient, outpatient, and emergency department areas for pediatric-only and nonpediatric-only populations. Drug-dose alerts were evaluated during a 3-month period. Drug-dose alerts fired on 12% of orders (104 098/834 911). System-level and drug-specific strategies to decrease drug-dose alerts were analyzed. System-level strategies included: (1) turning off all minimum drug-dosing alerts, (2) turning off all incomplete information drug-dosing alerts, (3) increasing the maximum single-dose drug-dose alert threshold to 125%, (4) increasing the daily dose maximum drug-dose alert threshold to 125%, and (5) increasing the dose frequency drug-dose alert threshold to more than 2 doses per day above initial threshold. Drug-specific strategies included changing drug-specific maximum single and maximum daily drug-dose alerting parameters for the top 22 drug categories by alert frequency. System-level approaches decreased alerting to 5% (46 988/834 911) and drug-specific approaches decreased alerts to 3% (25 455/834 911). Drug-dose alerts varied between care settings and patient populations. © The Author 2017. Published by Oxford University Press on behalf of the American Medical Informatics Association. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

An assessment of the doses received by members of the public in Japan following the nuclear accident at Fukushima Daiichi nuclear power plant.

PubMed

Bedwell, P; Mortimer, K; Wellings, J; Sherwood, J; Leadbetter, S J; Haywood, S M; Charnock, T; Jones, A R; Hort, M C

2015-12-01

The earthquake and tsunami on 11 March 2011, centred off the east coast of Japan, caused considerable destruction and substantial loss of life along large swathes of the Japanese coastline. The tsunami damaged the Fukushima Daiichi nuclear power plant (NPP), resulting in prolonged releases of radioactive material into the environment. This paper assesses the doses received by members of the public in Japan. The assessment is based on an estimated source term and atmospheric dispersion modelling rather than monitoring data. It is evident from this assessment that across the majority of Japan the estimates of dose are very low, for example they are estimated to be less than the annual average dose from natural background radiation in Japan. Even in the regions local to Fukushima Daiichi NPP (and not affected by any form of evacuation) the maximum lifetime effective dose is estimated to be well below the cumulative natural background dose over the same period. The impact of the urgent countermeasures on the estimates of dose was considered. And the relative contribution to dose from the range of exposure pathways and radionuclides were evaluated. Analysis of estimated doses focused on the geographic irregularity and the impact of the meteorological conditions. For example the dose to an infant's thyroid received over the first year was estimated to be greater in Hirono than in the non-evacuated region of Naraha, despite Hirono being further from the release location. A number of factors were identified and thought to contribute towards this outcome, including the local wind pattern which resulted in the recirculation of part of the release. The non-uniform nature of dose estimates strengthens the case for evaluations based on dispersion modelling.

First radon measurements and occupational exposure assessments in underground geodynamic laboratory the Polish Academy of Sciences Space Research Centre in Książ Castle (SW Poland).

PubMed

Fijałkowska-Lichwa, Lidia; Przylibski, Tadeusz A

2016-12-01

The article presents the results of the first radon activity concentration measurements conducted continuously between 17 th May 2014 and 16 th May 2015 in the underground geodynamic laboratory of the Polish Academy of Sciences Space Research Centre in Książ. The data were registered with the use of three Polish semiconductor SRDN-3 detectors located the closest (SRDN-3 No. 6) to and the furthest (SRDN-3 No. 3) from the facility entrance, and in the fault zone (SRDN-3 No. 4). The study was conducted to characterize the radon behaviour and check it possibility to use with reference to long- and short-term variations of radon activity concentration observed in sedimentary rocks strongly fractured and intersected by systems of multiple faults, for integrated comparative assessments of changes in local orogen kinetics. The values of radon activity concentration in the underground geodynamic laboratory of the Polish Academy of Sciences (PAN) Space Research Centre in Książ undergo changes of a distinctly seasonal character. The highest values of radon activity concentration are recorded from late spring (May/June) to early autumn (October), and the lowest - from November to April. Radon activity concentrations varied depending on the location of measurement points. Between late spring and autumn they ranged from 800 Bq·m -3 to 1200 Bq·m -3 , and even 3200 Bq·m -3 in the fault zone. Between November and April, values of radon activity concentration are lower, ranging from 500 Bq·m -3 to 1000 Bq·m -3 and 2700 Bq·m -3 in the fault zone. The values of radon activity concentration recorded in the studied facility did not undergo short-term changes in either the whole annual measuring cycle or any of its months. Effective doses received by people staying in the underground laboratory range from 0.001 mSv/h to 0.012 mSv/h. The mean annual effective dose, depending on the measurement site, equals 1 or is slightly higher than 10 mSv/year, while the maximum dose exceeds 20 mSv/year. The estimated annual effective doses are comparable to the standard value of 20 mSv/year defined by Polish law for people employed in the conditions of radiation exposure. They are also in the range of annual effective dose value (8 mSv/year) recommended in workplaces by International Commission on Radiation Protection. Copyright © 2016 Elsevier Ltd. All rights reserved.

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

PubMed

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.

New Stochastic Annual Limits on Intake for Selected Radionuclides

DOE Office of Scientific and Technical Information (OSTI.GOV)

Carbaugh, Eugene H.

Annual limits on intake (ALI) have historically been tabulated by the International Commission on Radiological Protection (e.g., ICRP 1979, 1961) and also by the Environmental Protection Agency (EPA 1988). These compilations have been rendered obsolete by more recent ICRP dosimetry methods, and, rather than provide new ALIs, the ICRP has opted instead to provide committed dose coefficients from which an ALI can be determined by a user for a specific set of conditions. The U.S. Department of Energy historically has referenced compilations of ALIs and has defined their method of calculation in its radiation protection regulation (10 CFDR 835), butmore » has never provided a specific compilation. Under June 2007 amendments to 10 CFR 835, ALIs can be calculated by dividing an appropriate dose limit, either 5-rem (0.05 Sv) effective dose or 50 rem (0.5 Sv) equivalent dose to an individual organ or tissue, by an appropriate committed dose coefficient. When based on effective dose, the ALI is often referred to as a stochastic annual limit on intake (SALI), and when based on the individual organ or tissue equivalent limit, it has often been called a deterministic annual limit on intake (DALI).« less

[Estimation of Maximum Entrance Skin Dose during Cerebral Angiography].

PubMed

Kawauchi, Satoru; Moritake, Takashi; Hayakawa, Mikito; Hamada, Yusuke; Sakuma, Hideyuki; Yoda, Shogo; Satoh, Masayuki; Sun, Lue; Koguchi, Yasuhiro; Akahane, Keiichi; Chida, Koichi; Matsumaru, Yuji

2015-09-01

Using radio-photoluminescence glass dosimeter, we measured the entrance skin dose (ESD) in 46 cases and analyzed the correlations between maximum ESD and angiographic parameters [total fluoroscopic time (TFT); number of digital subtraction angiography (DSA) frames, air kerma at the interventional reference point (AK), and dose-area product (DAP)] to estimate the maximum ESD in real time. Mean (± standard deviation) maximum ESD, dose of the right lens, and dose of the left lens were 431.2 ± 135.8 mGy, 33.6 ± 15.5 mGy, and 58.5 ± 35.0 mGy, respectively. Correlation coefficients (r) between maximum ESD and TFT, number of DSA frames, AK, and DAP were r=0.379 (P<0.01), r=0.702 (P<0.001), r=0.825 (P<0.001), and r=0.709 (P<0.001), respectively. AK was identified as the most useful parameter for real-time prediction of maximum ESD. This study should contribute to the development of new diagnostic reference levels in our country.

40 CFR 464.34 - New source performance standards.

Code of Federal Regulations, 2012 CFR

2012-07-01

...-continuous dischargers, annual average mass standards and maximum day and maximum for monthly average concentration (mg/l) standards shall apply. Concentration standards and annual average mass standards shall only... 40 Protection of Environment 31 2012-07-01 2012-07-01 false New source performance standards. 464...

40 CFR 464.34 - New source performance standards.

Code of Federal Regulations, 2014 CFR

2014-07-01

...-continuous dischargers, annual average mass standards and maximum day and maximum for monthly average concentration (mg/l) standards shall apply. Concentration standards and annual average mass standards shall only... 40 Protection of Environment 30 2014-07-01 2014-07-01 false New source performance standards. 464...

40 CFR 464.34 - New source performance standards.

Code of Federal Regulations, 2013 CFR

2013-07-01

...-continuous dischargers, annual average mass standards and maximum day and maximum for monthly average concentration (mg/l) standards shall apply. Concentration standards and annual average mass standards shall only... 40 Protection of Environment 31 2013-07-01 2013-07-01 false New source performance standards. 464...

Center of cancer systems biology second annual workshop--tumor metronomics: timing and dose level dynamics.

PubMed

Hahnfeldt, Philip; Hlatky, Lynn; Klement, Giannoula Lakka

2013-05-15

Metronomic chemotherapy, the delivery of doses in a low, regular manner so as to avoid toxic side effects, was introduced over 12 years ago in the face of substantial clinical and preclinical evidence supporting its tumor-suppressive capability. It constituted a marked departure from the classic maximum-tolerated dose (MTD) strategy, which, given its goal of rapid eradication, uses dosing sufficiently intense to require rest periods between cycles to limit toxicity. Even so, upfront tumor eradication is frequently not achieved with MTD, whereupon a de facto goal of longer-term tumor control is often pursued. As metronomic dosing has shown tumor control capability, even for cancers that have become resistant to the same drug delivered under MTD, the question arises whether it may be a preferable alternative dosing approach from the outset. To date, however, our knowledge of the coupled dynamics underlying metronomic dosing is neither sufficiently well developed nor widely enough disseminated to establish its actual potential. Meeting organizers thus felt the time was right, armed with new quantitative approaches, to call a workshop on "Tumor Metronomics: Timing and Dose Level Dynamics" to explore prospects for gaining a deeper, systems-level appreciation of the metronomics concept. The workshop proved to be a forum in which experts from the clinical, biologic, mathematical, and computational realms could work together to clarify the principles and underpinnings of metronomics. Among other things, the need for significant shifts in thinking regarding endpoints to be used as clinical standards of therapeutic progress was recognized. ©2013 AACR.

Low-dose chest computed tomography for lung cancer screening among Hodgkin lymphoma survivors: a cost-effectiveness analysis.

PubMed

Wattson, Daniel A; Hunink, M G Myriam; DiPiro, Pamela J; Das, Prajnan; Hodgson, David C; Mauch, Peter M; Ng, Andrea K

2014-10-01

Hodgkin lymphoma (HL) survivors face an increased risk of treatment-related lung cancer. Screening with low-dose computed tomography (LDCT) may allow detection of early stage, resectable cancers. We developed a Markov decision-analytic and cost-effectiveness model to estimate the merits of annual LDCT screening among HL survivors. Population databases and HL-specific literature informed key model parameters, including lung cancer rates and stage distribution, cause-specific survival estimates, and utilities. Relative risks accounted for radiation therapy (RT) technique, smoking status (>10 pack-years or current smokers vs not), age at HL diagnosis, time from HL treatment, and excess radiation from LDCTs. LDCT assumptions, including expected stage-shift, false-positive rates, and likely additional workup were derived from the National Lung Screening Trial and preliminary results from an internal phase 2 protocol that performed annual LDCTs in 53 HL survivors. We assumed a 3% discount rate and a willingness-to-pay (WTP) threshold of $50,000 per quality-adjusted life year (QALY). Annual LDCT screening was cost effective for all smokers. A male smoker treated with mantle RT at age 25 achieved maximum QALYs by initiating screening 12 years post-HL, with a life expectancy benefit of 2.1 months and an incremental cost of $34,841/QALY. Among nonsmokers, annual screening produced a QALY benefit in some cases, but the incremental cost was not below the WTP threshold for any patient subsets. As age at HL diagnosis increased, earlier initiation of screening improved outcomes. Sensitivity analyses revealed that the model was most sensitive to the lung cancer incidence and mortality rates and expected stage-shift from screening. HL survivors are an important high-risk population that may benefit from screening, especially those treated in the past with large radiation fields including mantle or involved-field RT. Screening may be cost effective for all smokers but possibly not for nonsmokers despite a small life expectancy benefit. Copyright © 2014 Elsevier Inc. All rights reserved.

50 CFR 259.34 - Minimum and maximum deposits; maximum time to deposit.

Code of Federal Regulations, 2010 CFR

2010-10-01

... B objective. A time longer than 10 years, either by original scheduling or by subsequent extension... OCEANIC AND ATMOSPHERIC ADMINISTRATION, DEPARTMENT OF COMMERCE AID TO FISHERIES CAPITAL CONSTRUCTION FUND...) Minimum annual deposit. The minimum annual (based on each party's taxable year) deposit required by the...

ASSESSMENT OF RADON IN SOIL AND WATER IN DIFFERENT REGIONS OF KOLHAPUR DISTRICT, MAHARASHTRA, INDIA.

PubMed

Raste, P M; Sahoo, B K; Gaware, J J; Sharma, Anil; Waikar, M R; Shaikh, A A; Sonkawade, R G

2018-03-19

Researchers have already established that inhalation of high radon concentration is hazardous to human health. Radon concentration has been measured in water and soil, in various part of Kolhapur district has been carried out by the AQTEK Smart RnDuo which is an active device technique. The observed minimum value of the radon mass exhalation rate of the soil is 13.16 ± 0.83 mBq/kg/h and maximum is 35.11 ± 1.84 mBq/kg/h. The minimum value of the Radon concentration in water is 0.33 ± 0.052 Bq/L and maximum is 7.32 ± 0.078 Bq/L. These values of radon concentration are below the action of recommended level by the USEPA, which is set as the maximum contaminant level of 11.1-148 Bq/L of radon in drinking water. Total annual effective dose rate of water is 11 μSv/y. The purpose of present study is to assess radiological risk from consumption of water that provide in Kolhapur district and to evaluate the radon mass exhalation rate of soil in few places of Kolhapur district.

Radioactivity Risk Assessment of Radon and Gamma Dose at One Uranium Tailings Pond in China

NASA Astrophysics Data System (ADS)

Lou, Yalong; Liu, Yong; Peng, Guowen; Zhao, Guodong; Zhang, Yan; Yang, Zhu

2018-01-01

A year-long monitoring of gamma radiation effective dose rate and radon concentration had been done in the reservoir area of one uranium tailings pond in Hunan province (The monitoring area included indoor and outdoor area of residential buildings and workshops, tailings dam slope). Afterwards, the annual effective radiation dose of the people in that radiation environment had been calculated based on the results of monitoring, as well as a radiation risk assessment. According to the assessment, gamma radiation effective dose rate and radon concentration in the monitoring area were low, and the annual effective radiation dose was far below the international standard (30mSv), which showed that the radiation would not put the people’s health at risk. However, the annual effective radiation dose of gamma was far above that of radon in the area of uranium tailings pond; therefore, it’s advisable to take quarantine measures in in the area of uranium tailings pond to keep the surrounding residents away from unnecessary ionizing radiation.

Probabilistic properties of the date of maximum river flow, an approach based on circular statistics in lowland, highland and mountainous catchment

NASA Astrophysics Data System (ADS)

Rutkowska, Agnieszka; Kohnová, Silvia; Banasik, Kazimierz

2018-04-01

Probabilistic properties of dates of winter, summer and annual maximum flows were studied using circular statistics in three catchments differing in topographic conditions; a lowland, highland and mountainous catchment. The circular measures of location and dispersion were used in the long-term samples of dates of maxima. The mixture of von Mises distributions was assumed as the theoretical distribution function of the date of winter, summer and annual maximum flow. The number of components was selected on the basis of the corrected Akaike Information Criterion and the parameters were estimated by means of the Maximum Likelihood method. The goodness of fit was assessed using both the correlation between quantiles and a version of the Kuiper's and Watson's test. Results show that the number of components varied between catchments and it was different for seasonal and annual maxima. Differences between catchments in circular characteristics were explained using climatic factors such as precipitation and temperature. Further studies may include circular grouping catchments based on similarity between distribution functions and the linkage between dates of maximum precipitation and maximum flow.

Factors associated with higher oxytocin requirements in labor.

PubMed

Frey, Heather A; Tuuli, Methodius G; England, Sarah K; Roehl, Kimberly A; Odibo, Anthony O; Macones, George A; Cahill, Alison G

2015-09-01

To identify clinical characteristics associated with high maximum oxytocin doses in women who achieve complete cervical dilation. A retrospective nested case-control study was performed within a cohort of all term women at a single center between 2004 and 2008 who reached the second stage of labor. Cases were defined as women who had a maximum oxytocin dose during labor >20 mu/min, while women in the control group had a maximum oxytocin dose during labor of ≤20 mu/min. Exclusion criteria included no oxytocin administration during labor, multiple gestations, major fetal anomalies, nonvertex presentation, and prior cesarean delivery. Multiple maternal, fetal, and labor factors were evaluated with univariable analysis and multivariable logistic regression. Maximum oxytocin doses >20 mu/min were administered to 108 women (3.6%), while 2864 women received doses ≤20 mu/min. Factors associated with higher maximum oxytocin dose after adjusting for relevant confounders included maternal diabetes, birthweight >4000 g, intrapartum fever, administration of magnesium, and induction of labor. Few women who achieve complete cervical dilation require high doses of oxytocin. We identified maternal, fetal and labor factors that characterize this group of parturients.

Radiolytic Treatment of the Next-Generation Caustic-Side Solvent Extraction (NGS) Solvent and its Effect on the NGS Process

DOE PAGES

Roach, Benjamin D.; Williams, Neil J.; Duncan, Nathan C.; ...

2014-12-01

We show in this work that the solvent used in the Next Generation Caustic-Side Solvent Extraction (NGS) process can withstand a radiation dose well in excess of the dose it would receive in multiple years of treating legacy salt waste at the US Department of Energy Savannah River Site. The solvent was subjected to a maximum of 50 kGy of gamma radiation while in dynamic contact with each of the aqueous phases of the current NGS process, namely SRS-15 (a highly caustic waste simulant), sodium hydroxide scrub solution (0.025 M), and boric acid strip solution (0.01 M). Bench-top testing ofmore » irradiated solvent confirmed that irradiation has inconsequential impact on the extraction, scrubbing, and stripping performance of the solvent up to 13 times the estimated 0.73 kGy/y annual absorbed dose. Lastly, stripping performance is the most sensitive step to radiation, deteriorating more due to buildup of p-sec-butylphenol (SBP) and possibly other proton-ionizable products than to degradation of the guanidine suppressor, as shown by chemical analyses.« less

Radiolytic Treatment of the Next-Generation Caustic-Side Solvent Extraction (NGS) Solvent and its Effect on the NGS Process

DOE Office of Scientific and Technical Information (OSTI.GOV)

Roach, Benjamin D.; Williams, Neil J.; Duncan, Nathan C.

We show in this work that the solvent used in the Next Generation Caustic-Side Solvent Extraction (NGS) process can withstand a radiation dose well in excess of the dose it would receive in multiple years of treating legacy salt waste at the US Department of Energy Savannah River Site. The solvent was subjected to a maximum of 50 kGy of gamma radiation while in dynamic contact with each of the aqueous phases of the current NGS process, namely SRS-15 (a highly caustic waste simulant), sodium hydroxide scrub solution (0.025 M), and boric acid strip solution (0.01 M). Bench-top testing ofmore » irradiated solvent confirmed that irradiation has inconsequential impact on the extraction, scrubbing, and stripping performance of the solvent up to 13 times the estimated 0.73 kGy/y annual absorbed dose. Lastly, stripping performance is the most sensitive step to radiation, deteriorating more due to buildup of p-sec-butylphenol (SBP) and possibly other proton-ionizable products than to degradation of the guanidine suppressor, as shown by chemical analyses.« less

Estimation of the indoor radon and the annual effective dose from granite samples

NASA Astrophysics Data System (ADS)

Sola, P.; Srinuttrakul, W.; Kewsuwan, P.

2015-05-01

Inhalation of radon and thoron daughters increases the risk of lung cancer. The main sources of indoor radon are building materials. The aim of this research is to estimate the indoor radon and the annual effective dose from the building materials. Eighteen granite samples bought from the markets in Thailand were measured using an ionization chamber (ATMOS 12 DPX) for the radon concentration in air. Radon exhalation rates were calculated from the radon concentration in chamber. The indoor radon from the granite samples ranged from 10.04 to 55.32 Bq·m-2·h-1 with an average value of 20.30 Bq·m-2·h-1 and the annual effective dose ranged from 0.25 to 1.39 mSv·y-1 with an average value of 0.48 mSv·y-1. The results showed that the annual effective doses of three granite samples were higher than the annual exposure limit for the general public (1 mSv·y-1) recommended by the International Commission on Radiological Protection (ICRP). In addition, the relationship between the colours and radon exhalation rates of granite samples was also explained.

AVERAGE ANNUAL SOLAR UV DOSE OF THE CONTINENTAL US CITIZEN

EPA Science Inventory

The average annual solar UV dose of US citizens is not known, but is required for relative risk assessments of skin cancer from UV-emitting devices. We solved this problem using a novel approach. The EPA's "National Human Activity Pattern Survey" recorded the daily ou...

Extreme daily precipitation: the case of Serbia in 2014

NASA Astrophysics Data System (ADS)

Tošić, Ivana; Unkašević, Miroslava; Putniković, Suzana

2017-05-01

The extreme daily precipitation in Serbia was examined at 16 stations during the period 1961-2014. Two synoptic situations in May and September of 2014 were analysed, when extreme precipitation was recorded in western and eastern Serbia, respectively. The synoptic situation from 14 to 16 May 2014 remained nearly stationary over the western and central Serbia for the entire period. On 15 May 2014, the daily rainfall broke previous historical records in Belgrade (109.8 mm), Valjevo (108.2 mm) and Loznica (110 mm). Precipitation exceeded 200 mm in 72 h, producing the most catastrophic floods in the recent history of Serbia. In Negotin (eastern Serbia), daily precipitation of 161.3 mm was registered on 16 September 2014, which was the maximum value recorded during the period 1961-2014. The daily maximum in 2014 was registered at 6 out of 16 stations. The total annual precipitation for 2014 was the highest for the period 1961-2014 at almost all stations in Serbia. A non-significant positive trend was found for all precipitation indices: annual daily maximum precipitation, the total precipitation in consecutive 3 and 5 days, the total annual precipitation, and number of days with at least 10 and 20 mm of precipitation. The generalised extreme value distribution was fitted to the annual daily maximum precipitation. The estimated 100-year return levels were 123.4 and 147.4 mm for the annual daily maximum precipitation in Belgrade and Negotin, respectively.

Effect of wildfire and fireline construction on the annual depth of thaw in a black spruce permafrost forest in interior Alaska: a 36-year record of recovery

Treesearch

Leslie A. Viereck; Nancy R. Werdin-Pfisterer; Phyllis C. Adams; Kenji Yoshikawa

2008-01-01

Maximum thaw depths were measured annually in an unburned stand, a heavily burned stand, and a fireline in and adjacent to the 1971 Wickersham fire. Maximum thaw in the unburned black spruce stand ranged from 36 to 52 cm. In the burned stand, thaw increased each year to a maximum depth of 302 cm in 1995. In 1996, the entire layer of seasonal frost remained, creating a...

78 FR 19029 - Joint Industry Plan; Notice of Filing and Immediate Effectiveness of Amendment No. 27 to the...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-03-28

... metric by which the Participants calculate the annual increase in the Enterprise Maximum. Pursuant to... the mechanisms of, a national market system or otherwise in furtherance of the purposes of the Act... metric by which the Participants calculate the annual increase in the Enterprise Maximum. Paragraph (e...

24 CFR 880.503 - Maximum annual commitment and project account.

Code of Federal Regulations, 2010 CFR

2010-04-01

... may be contracted for in the ACC is the total of the contract rents and utility allowances for all... commitment exceeds the amount actually paid out under the Contract or ACC each year. Payments will be made... the Contract or ACC for a fiscal year exceeds the maximum annual commitment and would cause the amount...

24 CFR 880.503 - Maximum annual commitment and project account.

Code of Federal Regulations, 2011 CFR

2011-04-01

... may be contracted for in the ACC is the total of the contract rents and utility allowances for all... commitment exceeds the amount actually paid out under the Contract or ACC each year. Payments will be made... the Contract or ACC for a fiscal year exceeds the maximum annual commitment and would cause the amount...

Maximum tolerated dose of nalmefene in patients receiving epidural fentanyl and dilute bupivacaine for postoperative analgesia.

PubMed

Dougherty, T B; Porche, V H; Thall, P F

2000-04-01

This study investigated the ability of the modified continual reassessment method (MCRM) to determine the maximum tolerated dose of the opioid antagonist nalmefene, which does not reverse analgesia in an acceptable number of postoperative patients receiving epidural fentanyl in 0.075% bupivacaine. In the postanesthetic care unit, patients received a single intravenous dose of 0.25, 0.50, 0.75, or 1.00 microg/kg nalmefene. Reversal of analgesia was defined as an increase in pain score of two or more integers above baseline on a visual analog scale from 0 through 10 after nalmefene administration. Patients were treated in cohorts of one, starting with the lowest dose. The maximum tolerated dose of nalmefene was defined as that dose, among the four studied, with a final mean probability of reversal of anesthesia (PROA) closest to 0.20 (ie., a 20% chance of causing reversal). The modified continual reassessment method is an iterative Bayesian statistical procedure that, in this study, selected the dose for each successive cohort as that having a mean PROA closest to the preselected target PROA of 0.20. The modified continual reassessment method repeatedly updated the PROA of each dose level as successive patients were observed for presence or absence of ROA. After 25 patients, the maximum tolerated dose of nalmefene was selected as 0.50 microg/kg (final mean PROA = 0.18). The 1.00-microg/kg dose was never tried because its projected PROA was far above 0.20. The modified continual reassessment method facilitated determination of the maximum tolerated dose ofnalmefene . Operating characteristics of the modified continual reassessment method suggest it may be an effective statistical tool for dose-finding in trials of selected analgesic or anesthetic agents.

Protection of the public in situations of prolonged radiation exposure. The application of the Commission's system of radiological protection to controllable radiation exposure due to natural sources and long-lived radioactive residues.

PubMed

1999-01-01

This report provides guidance on the application of the ICRP system of radiological protection to prolonged exposure situations affecting members of the public. It addresses the general application of the Commission's system to the control of prolonged exposures resulting from practices and to the undertaking of interventions in prolonged exposure situations. Additionally, it provides recommendations on generic reference levels for such interventions. The report also considers some specific situations and discusses a number of issues that have been of concern, namely: natural radiation sources that may give rise to high doses; the restoration and rehabilitation of sites where human activities involving radioactive substances have been carried out; the return to 'normality' following an accident that has released radioactive substances to the environment; and the global marketing of commodities for public consumption that contain radioactive substances. Annexes provide some examples of prolonged exposure situations and discuss the radiological protection quantities, radiation-induced health effects and aspects of the Commission's system of radiological protection relevant to prolonged exposure. Quantitative recommendations for prolonged exposures are provided in the report. They must be interpreted with extreme caution; Chapters 4 and 5 stress the upper bound nature of the following values: Generic reference levels for intervention, in terms of existing total annual doses, are given as < approximately 100 mSv, above which intervention is almost always justifiable (situations for which the annual dose threshold for deterministic effects in relevant organs is exceeded will almost always require intervention), and < approximately 10 mSv, below which intervention is not likely to be justifiable (and above which it may be necessary). Intervention exemption levels for commodities, especially building materials, are expressed as an additional annual dose of approximately 1 mSv. The dose limit for exposures of the public from practices is expressed as aggregated (prolonged and transitory) additional annual doses from all relevant practices of 1 mSv. Dose constraints for sources within practices are expressed as an additional annual dose lower than 1 mSv (e.g. of approximately 0.3 mSv), which could be approximately 0.1 mSv for the prolonged exposure component. An exemption level for practices is expressed as an additional annual dose of approximately 0.01 mSv.

Radon exposure assessment for underground workers: a case of Seoul Subway Police officers in Korea.

PubMed

Song, Myeong Han; Chang, Byung-Uck; Kim, Yongjae; Cho, Kun-Woo

2011-11-01

The objective of this study is the systematic and individual assessment of the annual effective dose due to inhaled radon for the Seoul Subway Police officers, Korea. The annual average radon concentrations were found to be in the range of 18.9-114 Bq·m(-3) in their workplaces. The total annual effective doses which may likely to be received on duty were assessed to be in the range of 0.41-1.64 mSv·y(-1). These were well below the recommended action level 10 mSv·y(-1) by ICRP. However, the effective doses were higher than subway station staff in Seoul, Korea.

Georgia fishery study: implications for dose calculations. Revision 1

DOE Office of Scientific and Technical Information (OSTI.GOV)

Turcotte, M.D.S.

Fish consumption will contribute a major portion of the estimated individual and population doses from L-Reactor liquid releases and Cs-137 remobilization in Steel Creek. It is therefore important that the values for fish consumption used in dose calculations be as realistic as possible. Since publication of the L-Reactor Environmental Information Document (EID), data have become available on sport fishing in the Savannah River. These data provide SRP with a site-specific sport fish harvest and consumption values for use in dose calculations. The Georgia fishery data support the total population fish consumption and calculated dose reported in the EID. The datamore » indicate, however, that both the EID average and maximum individual fish consumption have been underestimated, although each to a different degree. The average fish consumption value used in the EID is approximately 3% below the lower limit of the fish consumption range calculated using the Georgia data. Maximum fish consumption in the EID has been underestimated by approximately 60%, and doses to the maximum individual should also be recalculated. Future dose calculations should utilize an average adult fish consumption value of 11.3 kg/yr, and a maximum adult fish consumption value of 34 kg/yr. Consumption values for the teen and child age groups should be increased proportionally: (1) teen average = 8.5; maximum = 25.9 kg/yr; and (2) child average = 3.6; maximum = 11.2 kg/yr. 8 refs.« less

20 CFR 211.14 - Maximum creditable compensation.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 20 Employees' Benefits 1 2010-04-01 2010-04-01 false Maximum creditable compensation. 211.14... CREDITABLE RAILROAD COMPENSATION § 211.14 Maximum creditable compensation. Maximum creditable compensation for calendar years after 1984 is the maximum annual taxable wage base defined in section 3231(e)(2)(B...

Evaluation of annual committed effective doses to members of the public in Morocco due to 238U and 232Th in various food materials.

PubMed

Misdaq, M A; Bourzik, W

2004-12-01

Uranium (238U) and thorium (232Th) concentrations were measured in different foods widely consumed in Morocco by using CR-39 and LR-115 type II solid state nuclear track detectors (SSNTDs). Annual committed effective doses due to 238U and 232Th intakes from the ingestion of the studied food materials were evaluated for different age groups of individuals, using the ICRP ingestion dose coefficients. The influence of the 238U and 232Th intakes and ages of individuals on the committed effective dose was investigated. Total annual intakes of 238U and 232Th for a typical food basket for adult members of the Moroccan population were estimated to be 451 +/- 27 Bq y(-1) and 359 +/- 20 Bq y(-1), corresponding to committed effective doses of (20 +/- 1) x 10(-6) Sv y(-1) and (83 +/- 5) x 10(-6) Sv y(-1), respectively.

[Temporal change in annual air temperature and heat island effect in a coastal city and an inland city at mid-latitude in China during 1956-1998].

PubMed

Chao, Lu-men; Sun, Jian-xin

2009-12-01

Temporal changes in air temperature and urban heat island (UHI) effects during 1956-1998 were compared between a coastal city, Ji' nan, and an inland city, Xi' an, which were similar in latitude, size and development. During 1956-1978, except that the annual mean minimum temperature in Ji' nan increased by 0.37 degrees C x 10 a(-1), the temperature variables in the two cities did not display any apparent trend. During 1979-1998, all temperature variables of the two cities showed an increasing trend. Comparing with that in Ji' nan, the increasing rate of annual mean maximum temperature and annual mean temperature in Xi' an was greater, but that of annual mean minimum temperature was smaller. In the two cities, heat island effect occurred during 1956-1978 but without any apparent trend, whereas during 1979-1998, this effect increased with time, especially in Xi' an where the annual mean minimum temperature and annual mean temperature increased by 0.22 degrees C x 10 a(-1) and 0.32 degrees C x 10 a(-1), respectively. Both the level and the inter-annual variation of the heat island effect were much greater in Ji' nan than in Xi' an, but the increasing rate of this effect was greater in Xi' an than in Ji' nan. Obvious differences were observed in the increasing rate of annual mean maximum air temperature, annual mean air temperature, and annual mean minimum temperature as well as the heat island effect in Ji' nan, whereas negligible differences were found in Xi' an. Among the three temperature variables, annual mean minimum temperature displayed the most obvious increasing trend and was most affected by heat island effect, while annual mean maximum temperature was most variable inter-annually. Geographical location not only affected the magnitude of urban warming, but also affected the mode of urban warming and the strength of heat island effect.

76 FR 79579 - Approval and Promulgation of Implementation Plans and Designation of Areas for Air Quality...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-12-22

... posting of the availability of the submittal on EPA's Adequacy Web site (at http://www.epa.gov/otaq... average annual fourth-highest daily maximum 8-hour average ozone concentration), if it had a 1-hour design... ozone standard is attained when the three-year average of the annual fourth-highest daily maximum 8-hour...

Evaluation of the annual Canadian biodosimetry network intercomparisons

PubMed Central

Wilkins, Ruth C.; Beaton-Green, Lindsay A.; Lachapelle, Sylvie; Kutzner, Barbara C.; Ferrarotto, Catherine; Chauhan, Vinita; Marro, Leonora; Livingston, Gordon K.; Boulay Greene, Hillary; Flegal, Farrah N.

2015-01-01

Abstract Purpose: To evaluate the importance of annual intercomparisons for maintaining the capacity and capabilities of a well-established biodosimetry network in conjunction with assessing efficient and effective analysis methods for emergency response. Materials and methods: Annual intercomparisons were conducted between laboratories in the Canadian National Biological Dosimetry Response Plan. Intercomparisons were performed over a six-year period and comprised of the shipment of 10–12 irradiated, blinded blood samples for analysis by each of the participating laboratories. Dose estimates were determined by each laboratory using the dicentric chromosome assay (conventional and QuickScan scoring) and where possible the cytokinesis block micronucleus (CBMN) assay. Dose estimates were returned to the lead laboratory for evaluation and comparison. Results: Individual laboratories performed comparably from year to year with only slight fluctuations in performance. Dose estimates using the dicentric chromosome assay were accurate about 80% of the time and the QuickScan method for scoring the dicentric chromosome assay was proven to reduce the time of analysis without having a significant effect on the dose estimates. Although analysis with the CBMN assay was comparable to QuickScan scoring with respect to speed, the accuracy of the dose estimates was greatly reduced. Conclusions: Annual intercomparisons are necessary to maintain a network of laboratories for emergency response biodosimetry as they evoke confidence in their capabilities. PMID:25670072

FDA-sunlamp recommended Maximum Timer Interval And Exposure Schedule: consensus ISO/CIE dose equivalence.

PubMed

Dowdy, John C; Czako, Eugene A; Stepp, Michael E; Schlitt, Steven C; Bender, Gregory R; Khan, Lateef U; Shinneman, Kenneth D; Karos, Manuel G; Shepherd, James G; Sayre, Robert M

2011-09-01

The authors compared calculations of sunlamp maximum exposure times following current USFDA Guidance Policy on the Maximum Timer Interval and Exposure Schedule, with USFDA/CDRH proposals revising these to equivalent erythemal exposures of ISO/CIE Standard Erythema Dose (SED). In 2003, [USFDA/CDRH proposed replacing their unique CDRH/Lytle] erythema action spectrum with the ISO/CIE erythema action spectrum and revising the sunlamp maximum exposure timer to 600 J m(-2) ISO/CIE effective dose, presented as being biologically equivalent. Preliminary analysis failed to confirm said equivalence, indicating instead ∼38% increased exposure when applying these proposed revisions. To confirm and refine this finding, a collaboration of tanning bed and UV lamp manufacturers compiled 89 UV spectra representing a broad sampling of U.S. indoor tanning equipment. USFDA maximum recommended exposure time (Te) per current sunlamp guidance and CIE erythemal effectiveness per ISO/CIE standard were calculated. The CIE effective dose delivered per Te averaged 456 J(CIE) m(-2) (SD = 0.17) or ∼4.5 SED. The authors found that CDRH's proposed 600 J(CIE) m(-2) recommended maximum sunlamp exposure exceeds current Te erythemal dose by ∼33%. The current USFDA 0.75 MED initial exposure was ∼0.9 SED, consistent with 1.0 SED initial dose in existing international sunlamp standards. As no sunlamps analyzed exceeded 5 SED, a revised maximum exposure of 500 J(CIE) m(-2) (∼80% of CDRH's proposal) should be compatible with existing tanning equipment. A tanning acclimatization schedule is proposed beginning at 1 SED thrice-weekly, increasing uniformly stepwise over 4 wk to a 5 SED maximum exposure in conjunction with a tan maintenance schedule of twice-weekly 5 SED sessions, as biologically equivalent to current USFDA sunlamp policy.

Statistical downscaling of CMIP5 outputs for projecting future maximum and minimum temperature over the Haihe River Bain, China

NASA Astrophysics Data System (ADS)

Yan, Tiezhu; Shen, Zhenyao; Heng, Lee; Dercon, Gerd

2016-04-01

Future climate change information is important to formulate adaptation and mitigation strategies for climate change. In this study, a statistical downscaling model (SDSM) was established using both NCEP reanalysis data and ground observations (daily maximum and minimum temperature) during the period 1971-2010, and then calibrated model was applied to generate the future maximum and minimum temperature projections using predictors from the two CMIP5 models (MPI-ESM-LR and CNRM-CM5) under two Representative Concentration Pathway (RCP2.6 and RCP8.5) during the period 2011-2100 for the Haihe River Basin, China. Compared to the baseline period, future change in annual and seasonal maximum and minimum temperature was computed after bias correction. The spatial distribution and trend change of annual maximum and minimum temperature were also analyzed using ensemble projections. The results shows that: (1)The downscaling model had a good applicability on reproducing daily and monthly mean maximum and minimum temperature over the whole basin. (2) Bias was observed when using historical predictors from CMIP5 models and the performance of CNRM-CM5 was a little worse than that of MPI-ESM-LR. (3) The change in annual mean maximum and minimum temperature under the two scenarios in 2020s, 2050s and 2070s will increase and magnitude of maximum temperature will be higher than minimum temperature. (4) The increase in temperature in the mountains and along the coastline is remarkably high than the other parts of the studies basin. (5) For annual maximum and minimum temperature, the significant upward trend will be obtained under RCP 8.5 scenario and the magnitude will be 0.37 and 0.39 ℃ per decade, respectively; the increase in magnitude under RCP 2.6 scenario will be upward in 2020s and then decrease in 2050s and 2070s, and the magnitude will be 0.01 and 0.01℃ per decade, respectively.

Modelling of extreme rainfall events in Peninsular Malaysia based on annual maximum and partial duration series

NASA Astrophysics Data System (ADS)

Zin, Wan Zawiah Wan; Shinyie, Wendy Ling; Jemain, Abdul Aziz

2015-02-01

In this study, two series of data for extreme rainfall events are generated based on Annual Maximum and Partial Duration Methods, derived from 102 rain-gauge stations in Peninsular from 1982-2012. To determine the optimal threshold for each station, several requirements must be satisfied and Adapted Hill estimator is employed for this purpose. A semi-parametric bootstrap is then used to estimate the mean square error (MSE) of the estimator at each threshold and the optimal threshold is selected based on the smallest MSE. The mean annual frequency is also checked to ensure that it lies in the range of one to five and the resulting data is also de-clustered to ensure independence. The two data series are then fitted to Generalized Extreme Value and Generalized Pareto distributions for annual maximum and partial duration series, respectively. The parameter estimation methods used are the Maximum Likelihood and the L-moment methods. Two goodness of fit tests are then used to evaluate the best-fitted distribution. The results showed that the Partial Duration series with Generalized Pareto distribution and Maximum Likelihood parameter estimation provides the best representation for extreme rainfall events in Peninsular Malaysia for majority of the stations studied. Based on these findings, several return values are also derived and spatial mapping are constructed to identify the distribution characteristic of extreme rainfall in Peninsular Malaysia.

The maximum single dose of resistant maltodextrin that does not cause diarrhea in humans.

PubMed

Kishimoto, Yuka; Kanahori, Sumiko; Sakano, Katsuhisa; Ebihara, Shukuko

2013-01-01

The objective of the present study was to determine the maximum dose of resistant maltodextrin (Fibersol)-2, a non-viscous water-soluble dietary fiber), that does not induce transitory diarrhea. Ten healthy adult subjects (5 men and 5 women) ingested Fibersol-2 at increasing dose levels of 0.7, 0.8, 0.9, 1.0, and 1.1 g/kg body weight (bw). Each administration was separated from the previous dose by an interval of 1 wk. The highest dose level that did not cause diarrhea in any subject was regarded as the maximum non-effective level for a single dose. The results showed that no subject of either sex experienced diarrhea at dose levels of 0.7, 0.8, 0.9, or 1.0 g/kg bw. At the highest dose level of 1.1 g/kg bw, no female subject experienced diarrhea, whereas 1 male subject developed diarrhea with muddy stools 2 h after ingestion of the test substance. Consequently, the maximum non-effective level for a single dose of the resistant maltodextrin Fibersol-2 is 1.0 g/kg bw for men and >1.1 g/kg bw for women. Gastrointestinal symptoms were gurgling sounds in 4 subjects (7 events) and flatus in 5 subjects (9 events), although no association with dose level was observed. These symptoms were mild and transient and resolved without treatment.

Measurement of (222)Rn concentration levels in drinking water and the associated health effects in the Southern part of West Bank - Palestine.

PubMed

Thabayneh, Khalil M

2015-09-01

Radon concentration and annual effective doses were measured in drinking water in the Southern Part of West Bank - Palestine, by using both passive and active techniques. 184 samples were collected from various sources i.e. tap water, groundwater, rain waters and mineral waters. It is found that the annual effective dose resulting from inhalation and ingestion of radon emanated from all types of drinking water is negligible compared to the total annual effective dose from indoor radon in the region. Results reveal that there is no significant public health risk from radon ingested and inhalation with drinking water in the study region. Copyright © 2015. Published by Elsevier Ltd.

Estimation of eye lens doses received by pediatric interventional cardiologists.

PubMed

Alejo, L; Koren, C; Ferrer, C; Corredoira, E; Serrada, A

2015-09-01

Maximum Hp(0.07) dose to the eye lens received in a year by the pediatric interventional cardiologists has been estimated. Optically stimulated luminescence dosimeters were placed on the eyes of an anthropomorphic phantom, whose position in the room simulates the most common irradiation conditions. Maximum workload was considered with data collected from procedures performed in the Hospital. None of the maximum values obtained exceed the dose limit of 20 mSv recommended by ICRP. Copyright © 2015 Elsevier Ltd. All rights reserved.

The importance of protection glasses during neuroangiographies: A study on radiation exposure at the lens of the primary operator.

PubMed

Tavares, J B; Sacadura-Leite, E; Matoso, T; Neto, L L; Biscoito, L; Campos, J; Sousa-Uva, A

2016-06-01

In interventional neuroradiology, few operators routinely use radiation protection glasses. Moreover, in most centers, radiation dose data only accounts for whole body dose without specific information on lens dose. In 2012, the International Commission on Radiological Protection advised that the threshold limit value for the lens should be 20 mSv/year instead of the previous 150 mSv/year limit. The purpose of this study was to compare the radiation dose in the operator's lens during real diagnostic and interventional neuroangiographies, either using or without lead protection glasses. Using the Educational Direct Dosimeter (EDD30 dosimeter), accumulated radiation dose in the lens was measured in 13 neuroangiographies: seven diagnostic and six interventional. Operators with and without radiation protection glasses were included and the sensor was placed near their left eye, closest to the radiation beam. Without glasses, the corrected mean dose of radiation in the lens was 8.02 µSv for diagnostic procedures and 168.57 µSv for interventional procedures. Using glasses, these values were reduced to 1.74 µSv and 33.24 µSv, respectively. Considering 20 mSv as the suggested annual limit of equivalent dose in the lens, neuroradiologists may perform up to 2,494 diagnostic procedures per year without protecting glasses, a number that increases to 11,494 when glasses are used consistently. Regarding intervention, a maximum of 119 procedures per year is advised if glasses are not used, whereas up to 602 procedures/year may be performed using this protection. Therefore, neuroradiologists should always wear radiation protection glasses. © The Author(s) 2016.

Oak Ridge Reservation Environmental Protection Rad Neshaps Radionuclide Inventory Web Database and Rad Neshaps Source and Dose Database

DOE PAGES

Scofield, Patricia A.; Smith, Linda Lenell; Johnson, David N.

2017-07-01

The U.S. Environmental Protection Agency promulgated national emission standards for emissions of radionuclides other than radon from US Department of Energy facilities in Chapter 40 of the Code of Federal Regulations (CFR) 61, Subpart H. This regulatory standard limits the annual effective dose that any member of the public can receive from Department of Energy facilities to 0.1 mSv. As defined in the preamble of the final rule, all of the facilities on the Oak Ridge Reservation, i.e., the Y–12 National Security Complex, Oak Ridge National Laboratory, East Tennessee Technology Park, and any other U.S. Department of Energy operations onmore » Oak Ridge Reservation, combined, must meet the annual dose limit of 0.1 mSv. At Oak Ridge National Laboratory, there are monitored sources and numerous unmonitored sources. To maintain radiological source and inventory information for these unmonitored sources, e.g., laboratory hoods, equipment exhausts, and room exhausts not currently venting to monitored stacks on the Oak Ridge National Laboratory campus, the Environmental Protection Rad NESHAPs Inventory Web Database was developed. This database is updated annually and is used to compile emissions data for the annual Radionuclide National Emission Standards for Hazardous Air Pollutants (Rad NESHAPs) report required by 40 CFR 61.94. It also provides supporting documentation for facility compliance audits. In addition, a Rad NESHAPs source and dose database was developed to import the source and dose summary data from Clean Air Act Assessment Package—1988 computer model files. As a result, this database provides Oak Ridge Reservation and facility-specific source inventory; doses associated with each source and facility; and total doses for the Oak Ridge Reservation dose.« less

Oak Ridge Reservation Environmental Protection Rad Neshaps Radionuclide Inventory Web Database and Rad Neshaps Source and Dose Database.

PubMed

Scofield, Patricia A; Smith, Linda L; Johnson, David N

2017-07-01

The U.S. Environmental Protection Agency promulgated national emission standards for emissions of radionuclides other than radon from US Department of Energy facilities in Chapter 40 of the Code of Federal Regulations (CFR) 61, Subpart H. This regulatory standard limits the annual effective dose that any member of the public can receive from Department of Energy facilities to 0.1 mSv. As defined in the preamble of the final rule, all of the facilities on the Oak Ridge Reservation, i.e., the Y-12 National Security Complex, Oak Ridge National Laboratory, East Tennessee Technology Park, and any other U.S. Department of Energy operations on Oak Ridge Reservation, combined, must meet the annual dose limit of 0.1 mSv. At Oak Ridge National Laboratory, there are monitored sources and numerous unmonitored sources. To maintain radiological source and inventory information for these unmonitored sources, e.g., laboratory hoods, equipment exhausts, and room exhausts not currently venting to monitored stacks on the Oak Ridge National Laboratory campus, the Environmental Protection Rad NESHAPs Inventory Web Database was developed. This database is updated annually and is used to compile emissions data for the annual Radionuclide National Emission Standards for Hazardous Air Pollutants (Rad NESHAPs) report required by 40 CFR 61.94. It also provides supporting documentation for facility compliance audits. In addition, a Rad NESHAPs source and dose database was developed to import the source and dose summary data from Clean Air Act Assessment Package-1988 computer model files. This database provides Oak Ridge Reservation and facility-specific source inventory; doses associated with each source and facility; and total doses for the Oak Ridge Reservation dose.

Oak Ridge Reservation Environmental Protection Rad Neshaps Radionuclide Inventory Web Database and Rad Neshaps Source and Dose Database

DOE Office of Scientific and Technical Information (OSTI.GOV)

Scofield, Patricia A.; Smith, Linda Lenell; Johnson, David N.

The U.S. Environmental Protection Agency promulgated national emission standards for emissions of radionuclides other than radon from US Department of Energy facilities in Chapter 40 of the Code of Federal Regulations (CFR) 61, Subpart H. This regulatory standard limits the annual effective dose that any member of the public can receive from Department of Energy facilities to 0.1 mSv. As defined in the preamble of the final rule, all of the facilities on the Oak Ridge Reservation, i.e., the Y–12 National Security Complex, Oak Ridge National Laboratory, East Tennessee Technology Park, and any other U.S. Department of Energy operations onmore » Oak Ridge Reservation, combined, must meet the annual dose limit of 0.1 mSv. At Oak Ridge National Laboratory, there are monitored sources and numerous unmonitored sources. To maintain radiological source and inventory information for these unmonitored sources, e.g., laboratory hoods, equipment exhausts, and room exhausts not currently venting to monitored stacks on the Oak Ridge National Laboratory campus, the Environmental Protection Rad NESHAPs Inventory Web Database was developed. This database is updated annually and is used to compile emissions data for the annual Radionuclide National Emission Standards for Hazardous Air Pollutants (Rad NESHAPs) report required by 40 CFR 61.94. It also provides supporting documentation for facility compliance audits. In addition, a Rad NESHAPs source and dose database was developed to import the source and dose summary data from Clean Air Act Assessment Package—1988 computer model files. As a result, this database provides Oak Ridge Reservation and facility-specific source inventory; doses associated with each source and facility; and total doses for the Oak Ridge Reservation dose.« less

Knowledge of appropriate acetaminophen doses and potential toxicities in an adult clinic population.

PubMed

Stumpf, Janice L; Skyles, Amy J; Alaniz, Cesar; Erickson, Steven R

2007-01-01

To evaluate the knowledge of appropriate doses and potential toxicities of acetaminophen and assess the ability to recognize products containing acetaminophen in an adult outpatient setting. Cross-sectional, prospective study. University adult general internal medicine (AGIM) clinic. 104 adult patients presenting to the clinic over consecutive weekdays in December 2003. Three-page, written questionnaire. Ability of patients to identify maximum daily doses and potential toxicities of acetaminophen and recognize products that contain acetaminophen. A large percentage of participants (68.3%) reported pain on a daily or weekly basis, and 78.9% reported use of acetaminophen in the past 6 months. Only 2 patients correctly identified the maximum daily dose of regular acetaminophen, and just 3 correctly identified the maximum dose of extra-strength acetaminophen. Furthermore, 28 patients were unsure of the maximum dose of either product. Approximately 63% of participants either had not received or were unsure whether information on the possible danger of high doses of acetaminophen had been previously provided to them. When asked to identify potential problems associated with high doses of acetaminophen, 43.3% of patients noted the liver would be affected. The majority of the patients (71.2%) recognized Tylenol as containing acetaminophen, but fewer than 15% correctly identified Vicodin, Darvocet, Tylox, Percocet, and Lorcet as containing acetaminophen. Although nearly 80% of this AGIM population reported recent acetaminophen use, their knowledge of the maximum daily acetaminophen doses and potential toxicities associated with higher doses was poor and appeared to be independent of education level, age, and race. This indicates a need for educational efforts to all patients receiving acetaminophen-containing products, especially since the ability to recognize multi-ingredient products containing acetaminophen was likewise poor.

Radiation exposure in the moon environment

NASA Astrophysics Data System (ADS)

Reitz, Guenther; Berger, Thomas; Matthiae, Daniel

2012-12-01

During a stay on the moon humans are exposed to elevated radiation levels due to the lack of substantial atmospheric and magnetic shielding compared to the Earth's surface. The absence of magnetic and atmospheric shielding allows cosmic rays of all energies to impinge on the lunar surface. Beside the continuous exposure to galactic cosmic rays (GCR), which increases the risk of cancer mortality, exposure through particles emitted in sudden nonpredictable solar particle events (SPE) may occur. SPEs show an enormous variability in particle flux and energy spectra and have the potential to expose space crew to life threatening doses. On Earth, the contribution to the annual terrestrial dose of natural ionizing radiation of 2.4 mSv by cosmic radiation is about 1/6, whereas the annual exposure caused by GCR on the lunar surface is roughly 380 mSv (solar minimum) and 110 mSv (solar maximum). The analysis of worst case scenarios has indicated that SPE may lead to an exposure of about 1 Sv. The only efficient measure to reduce radiation exposure is the provision of radiation shelters. Measurements on the lunar surface performed during the Apollo missions cover only a small energy band for thermal neutrons and are not sufficient to estimate the exposure. Very recently some data were added by the Radiation Dose Monitoring (RADOM) instrument operated during the Indian Chandrayaan Mission and the Cosmic Ray Telescope (CRaTER) instrument of the NASA LRO (Lunar Reconnaisance Orbiter) mission. These measurements need to be complemented by surface measurements. Models and simulations that exist describe the approximate radiation exposure in space and on the lunar surface. The knowledge on the radiation exposure at the lunar surface is exclusively based on calculations applying radiation transport codes in combination with environmental models. Own calculations are presented using Monte-Carlo simulations to calculate the radiation environment on the moon and organ doses on the surface of the moon for an astronaut in an EVA suit and are compared with measurements. Since it is necessary to verify/validate such calculations with measurement on the lunar surface, a description is given of a radiation detector for future detailed surface measurements. This device is proposed for the ESA Lunar Lander Mission and is capable to characterize the radiation field concerning particle fluencies, dose rates and energy transfer spectra for ionizing particles and to measure the dose contribution of secondary neutrons.

Surface dose measurements for highly oblique electron beams.

PubMed

Ostwald, P M; Kron, T

1996-08-01

Clinical applications of electrons may involve oblique incidence of beams, and although dose variations for angles up to 60 degrees from normal incidence are well documented, no results are available for highly oblique beams. Surface dose measurements in highly oblique beams were made using parallel-plate ion chambers and both standard LiF:Mg, Ti and carbon-loaded LiF Thermoluminescent Dosimeters (TLD). Obliquity factors (OBF) or surface dose at an oblique angle divided by the surface dose at perpendicular incidence, were obtained for electron energies between 4 and 20 MeV. Measurements were performed on a flat solid water phantom without a collimator at 100 cm SSD. Comparisons were also made to collimated beams. The OBFs of surface doses plotted against the angle of incidence increased to a maximum dose followed by a rapid dropoff in dose. The increase in OBF was more rapid for higher energies. The maximum OBF occurred at larger angles for higher-energy beams and ranged from 73 degrees for 4 MeV to 84 degrees for 20 MeV. At the dose maximum, OBFs were between 130% and 160% of direct beam doses, yielding surface doses of up to 150% of Dmax for the 20 MeV beam. At 2 mm depth the dose ratio was found to increase initially with angle and then decrease as Dmax moved closer to the surface. A higher maximum dose was measured at 2 mm depth than at the surface. A comparison of ion chamber types showed that a chamber with a small electrode spacing and large guard ring is required for oblique dose measurement. A semiempirical equation was used to model the dose increase at the surface with different energy electron beams.

31 CFR 351.45 - What happens if I purchase definitive Series EE savings bonds in excess of the maximum annual...

Code of Federal Regulations, 2010 CFR

2010-07-01

... 31 Money and Finance: Treasury 2 2010-07-01 2010-07-01 false What happens if I purchase definitive Series EE savings bonds in excess of the maximum annual amount? 351.45 Section 351.45 Money and Finance: Treasury Regulations Relating to Money and Finance (Continued) FISCAL SERVICE, DEPARTMENT OF THE TREASURY...

Uncertainties in estimating heart doses from 2D-tangential breast cancer radiotherapy.

PubMed

Lorenzen, Ebbe L; Brink, Carsten; Taylor, Carolyn W; Darby, Sarah C; Ewertz, Marianne

2016-04-01

We evaluated the accuracy of three methods of estimating radiation dose to the heart from two-dimensional tangential radiotherapy for breast cancer, as used in Denmark during 1982-2002. Three tangential radiotherapy regimens were reconstructed using CT-based planning scans for 40 patients with left-sided and 10 with right-sided breast cancer. Setup errors and organ motion were simulated using estimated uncertainties. For left-sided patients, mean heart dose was related to maximum heart distance in the medial field. For left-sided breast cancer, mean heart dose estimated from individual CT-scans varied from <1Gy to >8Gy, and maximum dose from 5 to 50Gy for all three regimens, so that estimates based only on regimen had substantial uncertainty. When maximum heart distance was taken into account, the uncertainty was reduced and was comparable to the uncertainty of estimates based on individual CT-scans. For right-sided breast cancer patients, mean heart dose based on individual CT-scans was always <1Gy and maximum dose always <5Gy for all three regimens. The use of stored individual simulator films provides a method for estimating heart doses in left-tangential radiotherapy for breast cancer that is almost as accurate as estimates based on individual CT-scans. Copyright © 2016. Published by Elsevier Ireland Ltd.

NAIRAS aircraft radiation model development, dose climatology, and initial validation.

PubMed

Mertens, Christopher J; Meier, Matthias M; Brown, Steven; Norman, Ryan B; Xu, Xiaojing

2013-10-01

[1] The Nowcast of Atmospheric Ionizing Radiation for Aviation Safety (NAIRAS) is a real-time, global, physics-based model used to assess radiation exposure to commercial aircrews and passengers. The model is a free-running physics-based model in the sense that there are no adjustment factors applied to nudge the model into agreement with measurements. The model predicts dosimetric quantities in the atmosphere from both galactic cosmic rays (GCR) and solar energetic particles, including the response of the geomagnetic field to interplanetary dynamical processes and its subsequent influence on atmospheric dose. The focus of this paper is on atmospheric GCR exposure during geomagnetically quiet conditions, with three main objectives. First, provide detailed descriptions of the NAIRAS GCR transport and dosimetry methodologies. Second, present a climatology of effective dose and ambient dose equivalent rates at typical commercial airline altitudes representative of solar cycle maximum and solar cycle minimum conditions and spanning the full range of geomagnetic cutoff rigidities. Third, conduct an initial validation of the NAIRAS model by comparing predictions of ambient dose equivalent rates with tabulated reference measurement data and recent aircraft radiation measurements taken in 2008 during the minimum between solar cycle 23 and solar cycle 24. By applying the criterion of the International Commission on Radiation Units and Measurements (ICRU) on acceptable levels of aircraft radiation dose uncertainty for ambient dose equivalent greater than or equal to an annual dose of 1 mSv, the NAIRAS model is within 25% of the measured data, which fall within the ICRU acceptable uncertainty limit of 30%. The NAIRAS model predictions of ambient dose equivalent rate are generally within 50% of the measured data for any single-point comparison. The largest differences occur at low latitudes and high cutoffs, where the radiation dose level is low. Nevertheless, analysis suggests that these single-point differences will be within 30% when a new deterministic pion-initiated electromagnetic cascade code is integrated into NAIRAS, an effort which is currently underway.

NAIRAS aircraft radiation model development, dose climatology, and initial validation

NASA Astrophysics Data System (ADS)

Mertens, Christopher J.; Meier, Matthias M.; Brown, Steven; Norman, Ryan B.; Xu, Xiaojing

2013-10-01

The Nowcast of Atmospheric Ionizing Radiation for Aviation Safety (NAIRAS) is a real-time, global, physics-based model used to assess radiation exposure to commercial aircrews and passengers. The model is a free-running physics-based model in the sense that there are no adjustment factors applied to nudge the model into agreement with measurements. The model predicts dosimetric quantities in the atmosphere from both galactic cosmic rays (GCR) and solar energetic particles, including the response of the geomagnetic field to interplanetary dynamical processes and its subsequent influence on atmospheric dose. The focus of this paper is on atmospheric GCR exposure during geomagnetically quiet conditions, with three main objectives. First, provide detailed descriptions of the NAIRAS GCR transport and dosimetry methodologies. Second, present a climatology of effective dose and ambient dose equivalent rates at typical commercial airline altitudes representative of solar cycle maximum and solar cycle minimum conditions and spanning the full range of geomagnetic cutoff rigidities. Third, conduct an initial validation of the NAIRAS model by comparing predictions of ambient dose equivalent rates with tabulated reference measurement data and recent aircraft radiation measurements taken in 2008 during the minimum between solar cycle 23 and solar cycle 24. By applying the criterion of the International Commission on Radiation Units and Measurements (ICRU) on acceptable levels of aircraft radiation dose uncertainty for ambient dose equivalent greater than or equal to an annual dose of 1 mSv, the NAIRAS model is within 25% of the measured data, which fall within the ICRU acceptable uncertainty limit of 30%. The NAIRAS model predictions of ambient dose equivalent rate are generally within 50% of the measured data for any single-point comparison. The largest differences occur at low latitudes and high cutoffs, where the radiation dose level is low. Nevertheless, analysis suggests that these single-point differences will be within 30% when a new deterministic pion-initiated electromagnetic cascade code is integrated into NAIRAS, an effort which is currently underway.

NAIRAS aircraft radiation model development, dose climatology, and initial validation

PubMed Central

Mertens, Christopher J; Meier, Matthias M; Brown, Steven; Norman, Ryan B; Xu, Xiaojing

2013-01-01

[1] The Nowcast of Atmospheric Ionizing Radiation for Aviation Safety (NAIRAS) is a real-time, global, physics-based model used to assess radiation exposure to commercial aircrews and passengers. The model is a free-running physics-based model in the sense that there are no adjustment factors applied to nudge the model into agreement with measurements. The model predicts dosimetric quantities in the atmosphere from both galactic cosmic rays (GCR) and solar energetic particles, including the response of the geomagnetic field to interplanetary dynamical processes and its subsequent influence on atmospheric dose. The focus of this paper is on atmospheric GCR exposure during geomagnetically quiet conditions, with three main objectives. First, provide detailed descriptions of the NAIRAS GCR transport and dosimetry methodologies. Second, present a climatology of effective dose and ambient dose equivalent rates at typical commercial airline altitudes representative of solar cycle maximum and solar cycle minimum conditions and spanning the full range of geomagnetic cutoff rigidities. Third, conduct an initial validation of the NAIRAS model by comparing predictions of ambient dose equivalent rates with tabulated reference measurement data and recent aircraft radiation measurements taken in 2008 during the minimum between solar cycle 23 and solar cycle 24. By applying the criterion of the International Commission on Radiation Units and Measurements (ICRU) on acceptable levels of aircraft radiation dose uncertainty for ambient dose equivalent greater than or equal to an annual dose of 1 mSv, the NAIRAS model is within 25% of the measured data, which fall within the ICRU acceptable uncertainty limit of 30%. The NAIRAS model predictions of ambient dose equivalent rate are generally within 50% of the measured data for any single-point comparison. The largest differences occur at low latitudes and high cutoffs, where the radiation dose level is low. Nevertheless, analysis suggests that these single-point differences will be within 30% when a new deterministic pion-initiated electromagnetic cascade code is integrated into NAIRAS, an effort which is currently underway. PMID:26213513

HADOC: a computer code for calculation of external and inhalation doses from acute radionuclide releases

DOE Office of Scientific and Technical Information (OSTI.GOV)

Strenge, D.L.; Peloquin, R.A.

The computer code HADOC (Hanford Acute Dose Calculations) is described and instructions for its use are presented. The code calculates external dose from air submersion and inhalation doses following acute radionuclide releases. Atmospheric dispersion is calculated using the Hanford model with options to determine maximum conditions. Building wake effects and terrain variation may also be considered. Doses are calculated using dose conversion factor supplied in a data library. Doses are reported for one and fifty year dose commitment periods for the maximum individual and the regional population (within 50 miles). The fractional contribution to dose by radionuclide and exposure modemore » are also printed if requested.« less

Occupational exposure due to naturally occurring radionuclide material in granite quarry industry.

PubMed

Ademola, J A

2012-02-01

The potential occupational exposure in granite quarry industry due to the presence of naturally occurring radioactive material (NORM) has been investigated. The activity concentrations of (40)K, (226)Ra and (232)Th were determined using gamma-ray spectroscopy method. The annual effective dose of workers through different exposure pathways was determined by model calculations. The total annual effective dose varied from 21.48 to 33.69 μSv y(-1). Inhalation dose contributes the highest to the total effective dose. The results obtained were much lower than the intervention exemption levels (1.0 mSv y(-1)) given in the International Commission on Radiological Protection Publication 82.

Occupational radiation exposure in nuclear medicine department in Kuwait

NASA Astrophysics Data System (ADS)

Alnaaimi, M.; Alkhorayef, M.; Omar, M.; Abughaith, N.; Alduaij, M.; Salahudin, T.; Alkandri, F.; Sulieman, A.; Bradley, D. A.

2017-11-01

Ionizing radiation exposure is associated with eye lens opacities and cataracts. Radiation workers with heavy workloads and poor protection measures are at risk for vision impairment or cataracts if suitable protection measures are not implemented. The aim of this study was to measure and evaluate the occupational radiation exposure in a nuclear medicine (NM) department. The annual average effective doses (Hp[10] and Hp[0.07]) were measured using calibrated thermos-luminescent dosimeters (TLDs; MCP-N [LiF:Mg,Cu,P]). Five categories of staff (hot lab staff, PET physicians, NM physicians, technologists, and nurses) were included. The average annual eye dose (Hp[3]) for NM staff, based on measurements for a typical yearly workload of >7000 patients, was 4.5 mSv. The annual whole body radiation (Hp[10]) and skin doses (Hp[0.07]) were 4.0 and 120 mSv, respectively. The measured Hp(3), Hp(10), and Hp(0.07) doses for all NM staff categories were below the dose limits described in ICRP 2014 in light of the current practice. The results provide baseline data for staff exposure in NM in Kuwait. Radiation dose optimization measures are recommended to reduce NM staff exposure to its minimal value.

Recommendations of the Spanish brachytherapy group (GEB) of Spanish Society of Radiation Oncology (SEOR) and the Spanish Society of Medical Physics (SEFM) for high-dose rate (HDR) non melanoma skin cancer brachytherapy.

PubMed

Rodríguez, S; Arenas, M; Gutierrez, C; Richart, J; Perez-Calatayud, J; Celada, F; Santos, M; Rovirosa, A

2018-04-01

Clinical indications of brachytherapy in non-melanoma skin cancers, description of applicators and dosimetry recommendations are described based on the literature review, clinical practice and experience of Spanish Group of Brachytherapy and Spanish Society of Medical Physics reported in the XIV Annual Consensus Meeting on Non Melanoma Skin Cancer Brachytherapy held in Benidorm, Alicante (Spain) on October 21st, 2016. All the recommendations for which consensus was achieved are highlighted in blue. Regular and small surfaces may be treated with Leipzig, Valencia, flap applicators or electronic brachytherapy (EBT). For irregular surfaces, customized molds or interstitial implants should be employed. The dose is prescribed at a maximum depth of 3-4 mm of the clinical target volume/planning target volume (CTV/PTV) in all cases except in flaps or molds in which 5 mm is appropriate. Interstitial brachytherapy should be used for CTV/PTV >5 mm. Different total doses and fraction sizes are used with very similar clinical and toxicity results. Hypofractionation is very useful twice or 3 times a week, being comfortable for patients and practical for Radiotherapy Departments. In interstitial brachytherapy 2 fractions twice a day are applied.

Effects of radioactive contamination on Scots pines in the remote period after the Chernobyl accident.

PubMed

Geras'kin, Stanislav; Oudalova, Alla; Dikareva, Nina; Spiridonov, Sergey; Hinton, Thomas; Chernonog, Elena; Garnier-Laplace, Jacqueline

2011-08-01

A 6 year study of Scots pine populations inhabiting sites in the Bryansk region of Russia radioactively contaminated as a result of the Chernobyl accident is presented. In six study sites, (137)Cs activity concentrations and heavy metal content in soils, as well as (137)Cs, (90)Sr and heavy metal concentrations in cones were measured. Doses absorbed in reproduction organs of pine trees were calculated using a dosimetric model. The maximum annual dose absorbed at the most contaminated site was about 130 mGy. Occurrence of aberrant cells scored in the root meristem of germinated seeds collected from pine trees growing on radioactively contaminated territories for over 20 years significantly exceeded the reference levels during all 6 years of the study. The data suggest that cytogenetic effects occur in Scots pine populations due to the radioactive contamination. However, no consistent differences in reproductive ability were detected between the impacted and reference populations as measured by the frequency of abortive seeds. Even though the Scots pine populations have occupied radioactively contaminated territories for two decades, there were no clear indications of adaptation to the radiation, when measured by the number of aberrant cells in root meristems of seeds exposed to an additional acute dose of radiation.

Radionuclides (210Po and 210Pb) and Some Heavy Metals in Fish and Sediments in Lake Bafa, Turkey, and the Contribution of 210Po to the Radiation Dose.

PubMed

Manav, Ramazan; Uğur Görgün, Aysun; Filizok, Işık

2016-11-09

The pollution level of Lake Bafa was investigated by collecting fish samples { Dicentrarchus labrax (sea bass), Liza ramada (mullet) and Anguilla anguilla (eel)}, surface sediment, and core samples. In all these samples, 210 Po and 210 Pb concentrations were estimated, and total annual dose rates were obtained for each species. Some heavy metal (Cr, Ni, Pb, Cd, Mn, Fe, and Zn) concentration levels were obtained for the fish and a core sample. The sediment mass accumulation rate was found to be 3.27 g·m -2 ·day -1 (0.119 g·cm -2 ·y -1 ) from a core sample. The heavy metal concentrations in the vertical profile of samples from the core were also observed. The measured concentration of Zn, Pb, Cd, and Cr were between the ERL (effects range low) and ERM (effects range median) limits, while Ni concentrations were higher than the ERM limit. The observed concentrations of Cd, Pb, and Zn in fish samples did not exceed the limits in accordance with Turkish Food Regulations. Further, the maximum effective dose equivalent of 210 Po in the area was found to be 1.169 µSv·y -1 .

Low-Dose Chest Computed Tomography for Lung Cancer Screening Among Hodgkin Lymphoma Survivors: A Cost-Effectiveness Analysis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wattson, Daniel A., E-mail: dwattson@partners.org; Hunink, M.G. Myriam; DiPiro, Pamela J.

2014-10-01

Purpose: Hodgkin lymphoma (HL) survivors face an increased risk of treatment-related lung cancer. Screening with low-dose computed tomography (LDCT) may allow detection of early stage, resectable cancers. We developed a Markov decision-analytic and cost-effectiveness model to estimate the merits of annual LDCT screening among HL survivors. Methods and Materials: Population databases and HL-specific literature informed key model parameters, including lung cancer rates and stage distribution, cause-specific survival estimates, and utilities. Relative risks accounted for radiation therapy (RT) technique, smoking status (>10 pack-years or current smokers vs not), age at HL diagnosis, time from HL treatment, and excess radiation from LDCTs.more » LDCT assumptions, including expected stage-shift, false-positive rates, and likely additional workup were derived from the National Lung Screening Trial and preliminary results from an internal phase 2 protocol that performed annual LDCTs in 53 HL survivors. We assumed a 3% discount rate and a willingness-to-pay (WTP) threshold of $50,000 per quality-adjusted life year (QALY). Results: Annual LDCT screening was cost effective for all smokers. A male smoker treated with mantle RT at age 25 achieved maximum QALYs by initiating screening 12 years post-HL, with a life expectancy benefit of 2.1 months and an incremental cost of $34,841/QALY. Among nonsmokers, annual screening produced a QALY benefit in some cases, but the incremental cost was not below the WTP threshold for any patient subsets. As age at HL diagnosis increased, earlier initiation of screening improved outcomes. Sensitivity analyses revealed that the model was most sensitive to the lung cancer incidence and mortality rates and expected stage-shift from screening. Conclusions: HL survivors are an important high-risk population that may benefit from screening, especially those treated in the past with large radiation fields including mantle or involved-field RT. Screening may be cost effective for all smokers but possibly not for nonsmokers despite a small life expectancy benefit.« less

Storm Water Data 10-27-2016 for Upload to State Database.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Holland, Robert C.

In the California Industrial General Permit (IGP) 2014-0057-DWQ for storm water monitoring, effective July 1, 2015, there are 21 contaminants that have been assigned NAL (Numeric Action Level) values, both annual and instantaneous. For annual NALs, an exceedance occurs when the average of all analytical results from all samples taken at a facility during a reporting year for a given parameter exceeds an annual NAL value listed in Table 2 of the General Permit. For instantaneous maximum NALs, an exceedance occurs when two or more analytical results from samples taken for any parameter within a reporting year exceed the instantaneousmore » maximum NAL value (for TSS and O&G), or are outside of the instantaneous maximum NAL range (for pH) listed in Table 2. Table 2 is attached here for your review.« less

Assessment of Annual Effective Dose for Natural Radioactivity of Gamma Emitters in Biscuit Samples in Iraq.

PubMed

Abojassim, Ali Abid; Al-Alasadi, Lubna A; Shitake, Ahmed R; Al-Tememie, Faeq A; Husain, Afnan A

2015-09-01

Biscuits are an important type of food, widely consumed by babies in Iraq and other countries. This work uses gamma spectroscopy to measure the natural radioactivity due to long-lived gamma emitters in children's biscuits; it also estimates radiation hazard indices, that is, the radium equivalent activity, the representative of gamma level index, the internal hazard index, and the annual effective dose in children. Ten samples were collected from the Iraqi market from different countries of origin. The average specific activities for (226)Ra, (232)Th, and (40)K were 9.390, 3.1213, and 214.969 Bq/kg, respectively, but the average of the radium equivalent activity and the internal hazard index were 33.101 Bq/kg and 0.107, respectively. The total average annual effective dose from consumption by adults, children, and infants is estimated to be 0.655, 1.009, and 0.875 mSv, respectively. The values found for specific activity, radiation hazard indices, and annual effective dose in all samples in this study were lower than worldwide median values for all groups; therefore, these values are found to be safe.

Study of natural radioactivity in Mansehra granite, Pakistan: environmental concerns.

PubMed

Qureshi, Aziz Ahmed; Jadoon, Ishtiaq Ahmed Khan; Wajid, Ali Abbas; Attique, Ahsan; Masood, Adil; Anees, Muhammad; Manzoor, Shahid; Waheed, Abdul; Tubassam, Aneela

2014-03-01

A part of Mansehra Granite was selected for the assessment of radiological hazards. The average activity concentrations of (226)Ra, (232)Th and (40)K were found to be 27.32, 50.07 and 953.10 Bq kg(-1), respectively. These values are in the median range when compared with the granites around the world. Radiological hazard indices and annual effective doses were estimated. All of these indices were found to be within the criterion limits except outdoor external dose (82.38 nGy h(-1)) and indoor external dose (156.04 nGy h(-1)), which are higher than the world's average background levels of 51 and 55 nGy h(-1), respectively. These values correspond to an average annual effective dose of 0.867 mSv y(-1), which is less than the criterion limit of 1 mSv y(-1) (ICRP-103). Some localities in the Mansehra city have annual effective dose higher than the limit of 1 mSv y(-1). Overall, the Mansehra Granite does not pose any significant radiological health hazard in the outdoor or indoor.

Influence of intravenous opioid dose on postoperative ileus.

PubMed

Barletta, Jeffrey F; Asgeirsson, Theodor; Senagore, Anthony J

2011-07-01

Intravenous opioids represent a major component in the pathophysiology of postoperative ileus (POI). However, the most appropriate measure and threshold to quantify the association between opioid dose (eg, average daily, cumulative, maximum daily) and POI remains unknown. To evaluate the relationship between opioid dose, POI, and length of stay (LOS) and identify the opioid measure that was most strongly associated with POI. Consecutive patients admitted to a community teaching hospital who underwent elective colorectal surgery by any technique with an enhanced-recovery protocol postoperatively were retrospectively identified. Patients were excluded if they received epidural analgesia, developed a major intraabdominal complication or medical complication, or had a prolonged workup prior to surgery. Intravenous opioid doses were quantified and converted to hydromorphone equivalents. Classification and regression tree (CART) analysis was used to determine the dosing threshold for the opioid measure most associated with POI and define high versus low use of opioids. Risk factors for POI and prolonged LOS were determined through multivariate analysis. The incidence of POI in 279 patients was 8.6%. CART analysis identified a maximum daily intravenous hydromorphone dose of 2 mg or more as the opioid measure most associated with POI. Multivariate analysis revealed maximum daily hydromorphone dose of 2 mg or more (p = 0.034), open surgical technique (p = 0.045), and days of intravenous narcotic therapy (p = 0.003) as significant risk factors for POI. Variables associated with increased LOS were POI (p < 0.001), maximum daily hydromorphone dose of 2 mg or more (p < 0.001), and age (p = 0.005); laparoscopy (p < 0.001) was associated with a decreased LOS. Intravenous opioid therapy is significantly associated with POI and prolonged LOS, particularly when the maximum hydromorphone dose per day exceeds 2 mg. Clinicians should consider alternative, nonopioid-based pain management options when this occurs.

MEASUREMENT OF RADIATION DOSES TO THE EYE LENS DURING ORTHOPEDIC SURGERY USING AN C-ARM X-RAY SYSTEM.

PubMed

Suzuki, Akira; Matsubara, Kosuke; Sasa, Yuko

2018-04-01

The present study aimed to determine doses delivered to the eye lenses of surgeons while using the inverted-C-arm technique and the protective effect of leaded spectacles during orthopedic surgery. The kerma in air was measured at five positions on leaded glasses positioned near the eye lens and on the neck using small optically stimulated luminescence (OSL) dosemeters. The lens equivalent dose was also measured at the neck using an OSL dosemeter. The maximum equivalent dose to the eye lens and the maximum kerma were 0.8 mSv/month and 0.66 mGy/month, respectively. The leaded glasses reduced the exposure by ~60%. Even if the surgeons are exposed to the maximum dose of X-ray radiation for 5 years, the equivalent doses to the eye lens will not exceed the present limit recommended by the ICRP.

40 CFR Appendix to Subpart G of... - Applicant Questionnaire for Modification of Secondary Treatment Requirements

Code of Federal Regulations, 2011 CFR

2011-07-01

... upon which your application for a modification is based: —BOD5 ___ mg/L —Suspended solids ___ mg/L —pH... dry weather —average wet weather —maximum —annual average BOD5 (mg/L) for the following plant flows: —minimum —average dry weather —average wet weather —maximum —annual average Suspended solids (mg/L) for the...

40 CFR Appendix to Subpart G of... - Applicant Questionnaire for Modification of Secondary Treatment Requirements

Code of Federal Regulations, 2010 CFR

2010-07-01

... upon which your application for a modification is based: —BOD5 ___ mg/L —Suspended solids ___ mg/L —pH... dry weather —average wet weather —maximum —annual average BOD5 (mg/L) for the following plant flows: —minimum —average dry weather —average wet weather —maximum —annual average Suspended solids (mg/L) for the...

75 FR 62136 - Notice of Maximum Amount of Assistance Under the Individuals and Households Program

Federal Register 2010, 2011, 2012, 2013, 2014

2010-10-07

... DEPARTMENT OF HOMELAND SECURITY Federal Emergency Management Agency Notice of Maximum Amount of.... ACTION: Notice. SUMMARY: FEMA gives notice of the maximum amount for assistance under the Individuals and.... 5174, prescribes that FEMA must annually adjust the maximum amounts for assistance provided under the...

34 CFR 682.204 - Maximum loan amounts.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 34 Education 3 2010-07-01 2010-07-01 false Maximum loan amounts. 682.204 Section 682.204 Education..., DEPARTMENT OF EDUCATION FEDERAL FAMILY EDUCATION LOAN (FFEL) PROGRAM General Provisions § 682.204 Maximum... a full academic year, the maximum annual amount that the student may receive may not exceed the...

78 FR 64523 - Notice of Maximum Amount of Assistance Under the Individuals and Households Program

Federal Register 2010, 2011, 2012, 2013, 2014

2013-10-29

... DEPARTMENT OF HOMELAND SECURITY Federal Emergency Management Agency Notice of Maximum Amount of.... ACTION: Notice. SUMMARY: FEMA gives notice of the maximum amount for assistance under the Individuals and....C. 5174, prescribes that FEMA must annually adjust the maximum amount for assistance provided under...

34 CFR 674.12 - Loan maximums.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 34 Education 3 2010-07-01 2010-07-01 false Loan maximums. 674.12 Section 674.12 Education..., DEPARTMENT OF EDUCATION FEDERAL PERKINS LOAN PROGRAM General Provisions § 674.12 Loan maximums. (a) The maximum annual amount of Federal Perkins Loans and NDSLs an eligible student may borrow is— (1) $5,500 for...

77 FR 61425 - Notice of Maximum Amount of Assistance Under the Individuals and Households Program

Federal Register 2010, 2011, 2012, 2013, 2014

2012-10-09

... DEPARTMENT OF HOMELAND SECURITY Federal Emergency Management Agency Notice of Maximum Amount of.... ACTION: Notice. SUMMARY: FEMA gives notice of the maximum amount for assistance under the Individuals and....C. 5174, prescribes that FEMA must annually adjust the maximum amount for assistance provided under...

36 CFR 20.3 - Maximum number of permittees.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 36 Parks, Forests, and Public Property 1 2011-07-01 2011-07-01 false Maximum number of permittees... INTERIOR ISLE ROYALE NATIONAL PARK; COMMERCIAL FISHING § 20.3 Maximum number of permittees. Commercial fishermen to whom the annual revocable permits may be granted shall not exceed the maximum number of persons...

10 CFR 20.1207 - Occupational dose limits for minors.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 10 Energy 1 2012-01-01 2012-01-01 false Occupational dose limits for minors. 20.1207 Section 20.1207 Energy NUCLEAR REGULATORY COMMISSION STANDARDS FOR PROTECTION AGAINST RADIATION Occupational Dose Limits § 20.1207 Occupational dose limits for minors. The annual occupational dose limits for minors are...

10 CFR 20.1207 - Occupational dose limits for minors.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 10 Energy 1 2011-01-01 2011-01-01 false Occupational dose limits for minors. 20.1207 Section 20.1207 Energy NUCLEAR REGULATORY COMMISSION STANDARDS FOR PROTECTION AGAINST RADIATION Occupational Dose Limits § 20.1207 Occupational dose limits for minors. The annual occupational dose limits for minors are...

10 CFR 20.1207 - Occupational dose limits for minors.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 10 Energy 1 2010-01-01 2010-01-01 false Occupational dose limits for minors. 20.1207 Section 20.1207 Energy NUCLEAR REGULATORY COMMISSION STANDARDS FOR PROTECTION AGAINST RADIATION Occupational Dose Limits § 20.1207 Occupational dose limits for minors. The annual occupational dose limits for minors are...

10 CFR 20.1207 - Occupational dose limits for minors.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 10 Energy 1 2013-01-01 2013-01-01 false Occupational dose limits for minors. 20.1207 Section 20.1207 Energy NUCLEAR REGULATORY COMMISSION STANDARDS FOR PROTECTION AGAINST RADIATION Occupational Dose Limits § 20.1207 Occupational dose limits for minors. The annual occupational dose limits for minors are...

10 CFR 20.1207 - Occupational dose limits for minors.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 10 Energy 1 2014-01-01 2014-01-01 false Occupational dose limits for minors. 20.1207 Section 20.1207 Energy NUCLEAR REGULATORY COMMISSION STANDARDS FOR PROTECTION AGAINST RADIATION Occupational Dose Limits § 20.1207 Occupational dose limits for minors. The annual occupational dose limits for minors are...

24 CFR 884.105 - Maximum total ACC commitment and project account (private-owner/PHA projects).

Code of Federal Regulations, 2010 CFR

2010-04-01

... 24 Housing and Urban Development 4 2010-04-01 2010-04-01 false Maximum total ACC commitment and..., Scope and Basic Policies § 884.105 Maximum total ACC commitment and project account (private-owner/PHA projects). (a) Maximum total ACC commitment. The maximum total annual contribution that may be contracted...

24 CFR 884.105 - Maximum total ACC commitment and project account (private-owner/PHA projects).

Code of Federal Regulations, 2011 CFR

2011-04-01

... 24 Housing and Urban Development 4 2011-04-01 2011-04-01 false Maximum total ACC commitment and..., Scope and Basic Policies § 884.105 Maximum total ACC commitment and project account (private-owner/PHA projects). (a) Maximum total ACC commitment. The maximum total annual contribution that may be contracted...

Direct measurement of a patient's entrance skin dose during pediatric cardiac catheterization

PubMed Central

Sun, Lue; Mizuno, Yusuke; Iwamoto, Mari; Goto, Takahisa; Koguchi, Yasuhiro; Miyamoto, Yuka; Tsuboi, Koji; Chida, Koichi; Moritake, Takashi

2014-01-01

Children with complex congenital heart diseases often require repeated cardiac catheterization; however, children are more radiosensitive than adults. Therefore, radiation-induced carcinogenesis is an important consideration for children who undergo those procedures. We measured entrance skin doses (ESDs) using radio-photoluminescence dosimeter (RPLD) chips during cardiac catheterization for 15 pediatric patients (median age, 1.92 years; males, n = 9; females, n = 6) with cardiac diseases. Four RPLD chips were placed on the patient's posterior and right side of the chest. Correlations between maximum ESD and dose–area products (DAP), total number of frames, total fluoroscopic time, number of cine runs, cumulative dose at the interventional reference point (IRP), body weight, chest thickness, and height were analyzed. The maximum ESD was 80 ± 59 (mean ± standard deviation) mGy. Maximum ESD closely correlated with both DAP (r = 0.78) and cumulative dose at the IRP (r = 0.82). Maximum ESD for coiling and ballooning tended to be higher than that for ablation, balloon atrial septostomy, and diagnostic procedures. In conclusion, we directly measured ESD using RPLD chips and found that maximum ESD could be estimated in real-time using angiographic parameters, such as DAP and cumulative dose at the IRP. Children requiring repeated catheterizations would be exposed to high radiation levels throughout their lives, although treatment influences radiation dose. Therefore, the radiation dose associated with individual cardiac catheterizations should be analyzed, and the effects of radiation throughout the lives of such patients should be followed. PMID:24968708

Bone fractures following external beam radiotherapy and limb-preservation surgery for lower extremity soft tissue sarcoma: relationship to irradiated bone length, volume, tumor location and dose.

PubMed

Dickie, Colleen I; Parent, Amy L; Griffin, Anthony M; Fung, Sharon; Chung, Peter W M; Catton, Charles N; Ferguson, Peter C; Wunder, Jay S; Bell, Robert S; Sharpe, Michael B; O'Sullivan, Brian

2009-11-15

To examine the relationship between tumor location, bone dose, and irradiated bone length on the development of radiation-induced fractures for lower extremity soft tissue sarcoma (LE-STS) patients treated with limb-sparing surgery and radiotherapy (RT). Of 691 LE-STS patients treated from 1989 to 2005, 31 patients developed radiation-induced fractures. Analysis was limited to 21 fracture patients (24 fractures) who were matched based on tumor size and location, age, beam arrangement, and mean total cumulative RT dose to a random sample of 53 nonfracture patients and compared for fracture risk factors. Mean dose to bone, RT field size (FS), maximum dose to a 2-cc volume of bone, and volume of bone irradiated to >or=40 Gy (V40) were compared. Fracture site dose was determined by comparing radiographic images and surgical reports to fracture location on the dose distribution. For fracture patients, mean dose to bone was 45 +/- 8 Gy (mean dose at fracture site 59 +/- 7 Gy), mean FS was 37 +/- 8 cm, maximum dose was 64 +/- 7 Gy, and V40 was 76 +/- 17%, compared with 37 +/- 11 Gy, 32 +/- 9 cm, 59 +/- 8 Gy, and 64 +/- 22% for nonfracture patients. Differences in mean, maximum dose, and V40 were statistically significant (p = 0.01, p = 0.02, p = 0.01). Leg fractures were more common above the knee joint. The risk of radiation-induced fracture appears to be reduced if V40 <64%. Fracture incidence was lower when the mean dose to bone was <37 Gy or maximum dose anywhere along the length of bone was <59 Gy. There was a trend toward lower mean FS for nonfracture patients.

Modeling adverse event counts in phase I clinical trials of a cytotoxic agent.

PubMed

Muenz, Daniel G; Braun, Thomas M; Taylor, Jeremy Mg

2018-05-01

Background/Aims The goal of phase I clinical trials for cytotoxic agents is to find the maximum dose with an acceptable risk of severe toxicity. The most common designs for these dose-finding trials use a binary outcome indicating whether a patient had a dose-limiting toxicity. However, a patient may experience multiple toxicities, with each toxicity assigned an ordinal severity score. The binary response is then obtained by dichotomizing a patient's richer set of data. We contribute to the growing literature on new models to exploit this richer toxicity data, with the goal of improving the efficiency in estimating the maximum tolerated dose. Methods We develop three new, related models that make use of the total number of dose-limiting and low-level toxicities a patient experiences. We use these models to estimate the probability of having at least one dose-limiting toxicity as a function of dose. In a simulation study, we evaluate how often our models select the true maximum tolerated dose, and we compare our models with the continual reassessment method, which uses binary data. Results Across a variety of simulation settings, we find that our models compare well against the continual reassessment method in terms of selecting the true optimal dose. In particular, one of our models which uses dose-limiting and low-level toxicity counts beats or ties the other models, including the continual reassessment method, in all scenarios except the one in which the true optimal dose is the highest dose available. We also find that our models, when not selecting the true optimal dose, tend to err by picking lower, safer doses, while the continual reassessment method errs more toward toxic doses. Conclusion Using dose-limiting and low-level toxicity counts, which are easily obtained from data already routinely collected, is a promising way to improve the efficiency in finding the true maximum tolerated dose in phase I trials.

Radiation dose to technologists per nuclear medicine examination and estimation of annual dose.

PubMed

Bayram, Tuncay; Yilmaz, A Hakan; Demir, Mustafa; Sonmez, Bircan

2011-03-01

Conventional diagnostic nuclear medicine applications have been continuously increasing in most nuclear medicine departments in Turkey, but to our knowledge no one has studied the doses to technologists who perform nuclear medicine procedures. Most nuclear medicine laboratories do not have separate control rooms for technologists, who are quite close to the patient during data acquisition. Technologists must therefore stay behind lead shields while performing their task if they are to reduce the radiation dose received. The aim of this study was to determine external radiation doses to technologists during nuclear medicine procedures with and without a lead shield. Another aim was to investigate the occupational annual external radiation doses to Turkish technologists. This study used a Geiger-Müller detector to measure dose rates to technologists at various distances from patients (0.25, 0.50, 1, and 2 m and behind a lead shield) and determined the average time spent by technologists at these distances. Deep-dose equivalents to technologists were obtained. The following conventional nuclear medicine procedures were considered: thyroid scintigraphy performed using (99m)Tc pertechnetate, whole-body bone scanning performed using (99m)Tc-methylene diphosphonate, myocardial perfusion scanning performed using (99m)Tc-methoxyisobutyl isonitrile, and (201)Tl (thallous chloride) and renal scanning performed using (99m)Tc-dimercaptosuccinic acid. The measured deep-dose equivalent to technologists per procedure was within the range of 0.13 ± 0.05 to 0.43 ± 0.17 μSv using a lead shield and 0.21 ± 0.07 to 1.01 ± 0.46 μSv without a lead shield. Also, the annual individual dose to a technologist performing only a particular scintigraphic procedure throughout a year was estimated. For a total of 95 clinical cases (71 patients), effective external radiation doses to technologists were found to be within the permissible levels. This study showed that a 2-mm lead shield markedly reduced the external dose to technologists. The doses to technologists varied significantly for different diagnostic applications. Consequently, the estimated annual dose to a technologist performing only a particular scintigraphic procedure is very different from one type of procedure to another. The results of this study should help in determining the rotation time of technologists in different procedures and differences in their individual techniques.

Space radiation risks to the central nervous system

NASA Astrophysics Data System (ADS)

Cucinotta, Francis A.; Alp, Murat; Sulzman, Frank M.; Wang, Minli

2014-07-01

Central nervous system (CNS) risks which include during space missions and lifetime risks due to space radiation exposure are of concern for long-term exploration missions to Mars or other destinations. Possible CNS risks during a mission are altered cognitive function, including detriments in short-term memory, reduced motor function, and behavioral changes, which may affect performance and human health. The late CNS risks are possible neurological disorders such as premature aging, and Alzheimer's disease (AD) or other dementia. Radiation safety requirements are intended to prevent all clinically significant acute risks. However the definition of clinically significant CNS risks and their dependences on dose, dose-rate and radiation quality is poorly understood at this time. For late CNS effects such as increased risk of AD, the occurrence of the disease is fatal with mean time from diagnosis of early stage AD to death about 8 years. Therefore if AD risk or other late CNS risks from space radiation occur at mission relevant doses, they would naturally be included in the overall acceptable risk of exposure induced death (REID) probability for space missions. Important progress has been made in understanding CNS risks due to space radiation exposure, however in general the doses used in experimental studies have been much higher than the annual galactic cosmic ray (GCR) dose (∼0.1 Gy/y at solar maximum and ∼0.2 Gy/y at solar minimum with less than 50% from HZE particles). In this report we summarize recent space radiobiology studies of CNS effects from particle accelerators simulating space radiation using experimental models, and make a critical assessment of their relevance relative to doses and dose-rates to be incurred on a Mars mission. Prospects for understanding dose, dose-rate and radiation quality dependencies of CNS effects and extrapolation to human risk assessments are described.

Determination of naturally radioactive elements in chalk sticks by means of gamma spectroscopy

NASA Astrophysics Data System (ADS)

Abd El-Wahab, Magda; Morsy, Zeinab; El-Faramawy, Nabil

2010-04-01

The radiation hazards due to ingestion of chalkboard dust were investigated. Sixteen samples from three different origin fabricates were used. The estimation of radiation hazard indices were based on the evaluation of the concentration activities of the natural radionuclides 238U, 232Th and 40K. The radium equivalent activity, external hazard index, internal hazard index and the annual dose equivalent associated with the radionuclides were calculated and compared with international recommended values to assess the radiation hazard. The values of internal and external radiation hazard indices were found to be less than unity. The annual effective dose rate obtained, E eff, and the annual gonadal dose equivalent (AGDE) are found to be less than the limit of the doses recommended by the International Commission on Radiological Protection for the general public. The analytical results show that besides the main calcium content, some toxic elements, S, Mo and Pb and Ni and Pb, in the Egyptian and imported chalk stocks, respectively, existed.

Determination of naturally radioactive elements in chalk sticks by means of gamma spectroscopy

NASA Astrophysics Data System (ADS)

El-Wahab, Magda Abd; Morsy, Zeinab; El-Faramawy, Nabil

The radiation hazards due to ingestion of chalkboard dust were investigated. Sixteen samples from three different origin fabricates were used. The estimation of radiation hazard indices were based on the evaluation of the concentration activities of the natural radionuclides 238U, 232Th and 40K. The radium equivalent activity, external hazard index, internal hazard index and the annual dose equivalent associated with the radionuclides were calculated and compared with international recommended values to assess the radiation hazard. The values of internal and external radiation hazard indices were found to be less than unity. The annual effective dose rate obtained, Eeff, and the annual gonadal dose equivalent (AGDE) are found to be less than the limit of the doses recommended by the International Commission on Radiological Protection for the general public. The analytical results show that besides the main calcium content, some toxic elements, S, Mo and Pb and Ni and Pb, in the Egyptian and imported chalk stocks, respectively, existed.

Dexmedetomidine inhibits activation of the MAPK pathway and protects PC12 and NG108-15 cells from lidocaine-induced cytotoxicity at its maximum safe dose.

PubMed

Wang, Qiong; Tan, Yonghong; Zhang, Na; Xu, Yingyi; Wei, Wei; She, Yingjun; Bi, Xiaobao; Zhao, Baisong; Ruan, Xiangcai

2017-07-01

The developing brains of pediatric patients are highly vulnerable to anesthetic regimen (e.g., lidocaine), potentially causing neurological impairment. Recently, dexmedetomidine (DEX) has been used as an adjunct for sedation, and was shown to exert dose-dependent neuroprotective effects during brain injury. However, the maximum safe dose of DEX is unclear, and its protective effects against lidocaine-related neurotoxicity need to be confirmed. In this study, PC12 and NG108-15 cells were used to estimate safe, non-cytotoxic doses of DEX. We found that 100 and 60μM are the maximum safe dose of DEX for PC12 and NG108-15 cells, respectively, with no significant cytotoxicity. Lidocaine was found to remarkably inhibit cell vitality, but could be reversed by different doses of DEX, especially its maximum safe dose. Furthermore, the apoptosis induced by lidocaine was also assessed, and 100 and 60μM DEX showed optimal protective effects in PC12 and NG108-15 cells, respectively. Mechanistically, DEX activated the mitogen-activated protein kinase (MAPK) pathway, impaired caspase-3 expression, and enhanced anti-apoptotic factor Bcl-2 to resist lidocaine-induced apoptosis, indicating that the optimal dose of DEX alleviates lidocaine-induced cytotoxicity and should be considered in clinical application. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Is eye lens dosimetry needed in nuclear medicine?

PubMed

Wrzesień, M; Królicki, L; Albiniak, Ł; Olszewski, J

2018-06-01

The exact level of exposure experienced by nuclear medicine personnel, whose work often requires performing manual procedures involving radioactive isotopes, is associated with the form of radiation source used. The variety of radionuclides and medical procedures, and the yearly increase in the number of patients, as well as the change of the individual dose limit for the lens of the eye from a value of 150 mSv yr -1 to 20 mSv yr -1 , mean that issues of eye lens routine dosimetry become interesting from the radiation protection point of view. This paper presents an analysis of the exposure of the eye lenses of nuclear medicine department personnel, as well as those of personnel in the facilities that produce radiopharmaceuticals for the purpose of diagnosis by positron emission tomography, from the viewpoint of the advisability of routine eye lens exposure monitoring, taking into account changes in the dose limit for the lens of the eye. The paper considers the two most commonly used radionuclides for diagnostic purposes 99m Tc, 18 F, and-for therapeutic purposes- 131 I. Dose measurements were made using thermoluminescent detectors. The estimated exposure analysis identifies the cases when the maximum annual value of the personal dose equivalent, in terms of Hp(3), exceeds threefold the new limit value (20 mSv yr -1 ). It is recommended that Hp(3) doses be routinely monitored in the group of radiopharmacists who label pharmaceuticals with the radionuclide 99m Tc and in chemists working in 18 F-FDG quality control departments in production units, where this is carried out manually.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Loupot, S; Han, T; Salehpour, M

Purpose: To quantify the difference in dose to PTV-EVAL and OARs (skin and rib) as calculated by (TG43) and heterogeneous calculations (CCC). Methods: 25 patient plans (5 Contura and 20 SAVI) were selected for analysis. Clinical dose distributions were computed with a commercially available treatment planning algorithm (TG43-D-(w,w)) and then recomputed with a pre-clinical collapsed cone convolution algorithm (CCCD-( m,m)). PTV-EVAL coverage (V90%, V95%), and rib and skin maximum dose were compared via percent difference. Differences in dose to normal tissue (V150cc, V200cc of PTV-EVAL) were also compared. Changes in coverage and maximum dose to organs at risk are reportedmore » in percent change, (100*(TG43 − CCC) / TG43)), and changes in maximum dose to normal tissue are absolute change in cc (TG43 − CCC). Results: Mean differences in V90, V95, V150, and V200 for the SAVI cases were −0.2%, −0.4%, −0.03cc, and −0.14cc, respectively, with maximum differences of −0.78%, −1.7%, 1.28cc, and 1.01cc, respectively. Mean differences in the 0.1cc dose to the rib and skin were −1.4% and −0.22%, respectively, with maximum differences of −4.5% and 16%, respectively. Mean differences in V90, V95, V150, and V200 for the Contura cases were −1.2%, −2.1%, −1.8cc, and −0.59cc, respectively, with maximum differences of −2.0%, −3.16%, −2.9cc, and −0.76cc, respectively. Mean differences in the 0.1cc dose to the rib and skin were −2.6% and −3.9%, respectively, with maximum differences of −3.2% and −5.7%, respectively. Conclusion: The effects of translating clinical knowledge based on D-(w,w) to plans reported in D-(m,m) are minimal (2% or less) on average, but vary based on the type and placement of the device, source, and heterogeneity information.« less

A Randomized Phase 2 Study of Long-Acting TransCon GH vs Daily GH in Childhood GH Deficiency.

PubMed

Chatelain, Pierre; Malievskiy, Oleg; Radziuk, Klaudziya; Senatorova, Ganna; Abdou, Magdy O; Vlachopapadopoulou, Elpis; Skorodok, Yulia; Peterkova, Valentina; Leff, Jonathan A; Beckert, Michael

2017-05-01

TransCon Growth Hormone (GH) (Ascendis Pharma) is a long-acting recombinant sustained-release human GH prodrug in development for children with GH deficiency (GHD). To compare the pharmacokinetics, pharmacodynamics, safety, and efficacy of weekly TransCon GH to that of daily GH in prepubertal children with GHD. Randomized, open-label, active-controlled study of three doses of weekly TransCon GH versus daily Genotropin (Pfizer). Thirty-eight centers in 14 European countries and Egypt. Prepubertal male and female treatment-naïve children with GHD (n = 53). Subjects received one of three TransCon GH doses (0.14, 0.21, or 0.30 mg GH/kg/wk) or Genotropin 0.03 mg GH/kg/d for 26 weeks. GH and insulinlike growth factor-1 (IGF-1) levels, growth, adverse events, and immunogenicity. Both GH maximum concentration and area under the curve were similar following TransCon GH or Genotropin administration at comparable doses. A dose response was observed, with IGF-1 standard deviation scores increasing into the normal range for all three TransCon GH doses. Annualized mean height velocity for the three TransCon GH doses ranged from 11.9 cm to 13.9 cm, which was not statistically different from 11.6 cm for Genotropin. Adverse events were mild to moderate, and most were unrelated to the study drug. Injection site tolerance was good. One TransCon GH subject developed a low-titer, nonneutralizing antibody response to GH. The results suggest that long-acting TransCon GH is comparable to daily Genotropin for GH (pharmacokinetics) and IGF-1 (pharmacodynamics) levels, safety, and efficacy and support advancement into phase 3 development. Copyright © 2017 Endocrine Society

Assessment of radiation doses from residential smoke detectors that contain americium-241

NASA Astrophysics Data System (ADS)

Odonnell, F. R.; Etnier, E. L.; Holton, G. A.; Travis, C. C.

1981-10-01

External dose equivalents and internal dose commitments were estimated for individuals and populations from annual distribution, use, and disposal of 10 million ionization chamber smoke detectors that contain 110 kBq americium-241 each. Under exposure scenarios developed for normal distribution, use, and disposal using the best available information, annual external dose equivalents to average individuals were estimated to range from 4 fSv to 20 nSv for total body and from 7 fSv to 40 nSv for bone. Internal dose commitments to individuals under post disposal scenarios were estimated to range from 0.006 to 80 micro-Sv (0.0006 to 8 mrem) to total body and from 0.06 to 800 micro-Sv to bone. The total collective dose (the sum of external dose equivalents and 50-year internal dose commitments) for all individuals involved with distribution, use, or disposal of 10 million smoke detectors was estimated to be about 0.38 person-Sv (38 person-rem) to total body and 00 ft squared.

40 CFR 464.13 - Effluent limitations guidelines representing the degree of effluent reduction attainable by the...

Code of Federal Regulations, 2010 CFR

2010-07-01

... copper, lead, zinc, and total phenols. For non-continuous dischargers, annual average mass limitations....0771 0.0421 Lead (T) 0.0791 0.039 Zinc (T) 0.114 0.0431 Maximum for any 1 day Maximum for monthly average Annual average 1 (mg/l) 2 (mg/l) 2 Copper (T) 0.77 0.42 0.017 Lead (T) 0.79 0.39 0.022 Zinc (T) 1...

40 CFR 464.13 - Effluent limitations guidelines representing the degree of effluent reduction attainable by the...

Code of Federal Regulations, 2011 CFR

2011-07-01

... copper, lead, zinc, and total phenols. For non-continuous dischargers, annual average mass limitations....0771 0.0421 Lead (T) 0.0791 0.039 Zinc (T) 0.114 0.0431 Maximum for any 1 day Maximum for monthly average Annual average 1 (mg/l) 2 (mg/l) 2 Copper (T) 0.77 0.42 0.017 Lead (T) 0.79 0.39 0.022 Zinc (T) 1...

Formation, distribution and variability in snow cover on the Asian territory of the USSR

NASA Technical Reports Server (NTRS)

Pupkov, V. N.

1985-01-01

A description is given of maps compiled for annual and average multiple-year water reserves. The annual and average multiple-year maximum snow cover height for winter, extreme values of maximum snow reserves, and the average height and snow reserves at the end of each decade are shown. These maps were made for the entire Asian territory of the USSR, excluding Central Asia, Kamchatka Peninsula, and the Sakhalin Islands.

24 CFR 982.151 - Annual contributions contract.

Code of Federal Regulations, 2011 CFR

2011-04-01

... Contract and PHA Administration of Program § 982.151 Annual contributions contract. (a) Nature of ACC. (1) An annual contributions contract (ACC) is a written contract between HUD and a PHA. Under the ACC... owners and for the PHA administrative fee. The ACC specifies the maximum payment over the ACC term. The...

24 CFR 982.151 - Annual contributions contract.

Code of Federal Regulations, 2010 CFR

2010-04-01

... Contract and PHA Administration of Program § 982.151 Annual contributions contract. (a) Nature of ACC. (1) An annual contributions contract (ACC) is a written contract between HUD and a PHA. Under the ACC... owners and for the PHA administrative fee. The ACC specifies the maximum payment over the ACC term. The...

The Significance of the Record Length in Flood Frequency Analysis

NASA Astrophysics Data System (ADS)

Senarath, S. U.

2013-12-01

Of all of the potential natural hazards, flood is the most costly in many regions of the world. For example, floods cause over a third of Europe's average annual catastrophe losses and affect about two thirds of the people impacted by natural catastrophes. Increased attention is being paid to determining flow estimates associated with pre-specified return periods so that flood-prone areas can be adequately protected against floods of particular magnitudes or return periods. Flood frequency analysis, which is conducted by using an appropriate probability density function that fits the observed annual maximum flow data, is frequently used for obtaining these flow estimates. Consequently, flood frequency analysis plays an integral role in determining the flood risk in flood prone watersheds. A long annual maximum flow record is vital for obtaining accurate estimates of discharges associated with high return period flows. However, in many areas of the world, flood frequency analysis is conducted with limited flow data or short annual maximum flow records. These inevitably lead to flow estimates that are subject to error. This is especially the case with high return period flow estimates. In this study, several statistical techniques are used to identify errors caused by short annual maximum flow records. The flow estimates used in the error analysis are obtained by fitting a log-Pearson III distribution to the flood time-series. These errors can then be used to better evaluate the return period flows in data limited streams. The study findings, therefore, have important implications for hydrologists, water resources engineers and floodplain managers.

50 CFR 403.02 - Definitions.

Code of Federal Regulations, 2010 CFR

2010-10-01

... largest supportable within the ecosystem to the population level that results in maximum net productivity. Maximum net productivity is the greatest net annual increment in population numbers or biomass resulting...

The impact of inter-annual variability of annual cycle on long-term persistence of surface air temperature in long historical records

NASA Astrophysics Data System (ADS)

Deng, Qimin; Nian, Da; Fu, Zuntao

2018-02-01

Previous studies in the literature show that the annual cycle of surface air temperature (SAT) is changing in both amplitude and phase, and the SAT departures from the annual cycle are long-term correlated. However, the classical definition of temperature anomalies is based on the assumption that the annual cycle is constant, which contradicts the fact of changing annual cycle. How to quantify the impact of the changing annual cycle on the long-term correlation of temperature anomaly variability still remains open. In this paper, a recently developed data adaptive analysis tool, the nonlinear mode decomposition (NMD), is used to extract and remove time-varying annual cycle to reach the new defined temperature anomalies in which time-dependent amplitude of annual cycle has been considered. By means of detrended fluctuation analysis, the impact induced by inter-annual variability from the time-dependent amplitude of annual cycle has been quantified on the estimation of long-term correlation of long historical temperature anomalies in Europe. The results show that the classical climatology annual cycle is supposed to lack inter-annual fluctuation which will lead to a maximum artificial deviation centering around 600 days. This maximum artificial deviation is crucial to defining the scaling range and estimating the long-term persistence exponent accurately. Selecting different scaling range could lead to an overestimation or underestimation of the long-term persistence exponent. By using NMD method to extract the inter-annual fluctuations of annual cycle, this artificial crossover can be weakened to extend a wider scaling range with fewer uncertainties.

Temporal variations in the potential hydrological performance of extensive green roof systems

NASA Astrophysics Data System (ADS)

De-Ville, Simon; Menon, Manoj; Stovin, Virginia

2018-03-01

Existing literature provides contradictory information about variation in potential green roof hydrological performance over time. This study has evaluated a long-term hydrological monitoring record from a series of extensive green roof test beds to identify long-term evolutions and sub-annual (seasonal) variations in potential hydrological performance. Monitoring of nine differently-configured extensive green roof test beds took place over a period of 6 years in Sheffield, UK. Long-term evolutions and sub-annual trends in maximum potential retention performance were identified through physical monitoring of substrate field capacity over time. An independent evaluation of temporal variations in detention performance was undertaken through the fitting of reservoir-routing model parameters. Aggregation of the resulting retention and detention variations permitted the prediction of extensive green roof hydrological performance in response to a 1-in-30-year 1-h summer design storm for Sheffield, UK, which facilitated the comparison of multi and sub-annual hydrological performance variations. Sub-annual (seasonal) variation was found to be significantly greater than long-term evolution. Potential retention performance increased by up to 12% after 5-years, whilst the maximum sub-annual variation in potential retention was 27%. For vegetated roof configurations, a 4% long-term improvement was observed for detention performance, compared to a maximum 63% sub-annual variation. Consistent long-term reductions in detention performance were observed in unvegetated roof configurations, with a non-standard expanded-clay substrate experiencing a 45% reduction in peak attenuation over 5-years. Conventional roof configurations exhibit stable long-term hydrological performance, but are nonetheless subject to sub-annual variation.

Semi-annual Sq-variation in solar activity cycle

NASA Astrophysics Data System (ADS)

Pogrebnoy, V.; Malosiev, T.

The peculiarities of semi-annual variation in solar activity cycle have been studied. The data from observatories having long observational series and located in different latitude zones were used. The following observatories were selected: Huancayo (magnetic equator), from 1922 to 1959; Apia (low latitudes), from 1912 to 1961; Moscow (middle latitudes), from 1947 to 1965. Based on the hourly values of H-components, the average monthly diurnal amplitudes (a difference between midday and midnight values), according to five international quiet days, were computed. Obtained results were compared with R (relative sunspot numbers) in the ranges of 0-30R, 40-100R, and 140-190R. It was shown, that the amplitude of semi-annual variation increases with R, from minimum to maximum values, on average by 45%. At equatorial Huancayo observatory, the semi-annual Sq(H)-variation appears especially clearly: its maximums take place at periods of equinoxes (March-April, September-October), and minimums -- at periods of solstices (June-July, December-January). At low (Apia observatory) and middle (Moscow observatory) latitudes, the character of semi-annual variation is somewhat different: it appears during the periods of equinoxes, but considerably less than at equator. Besides, with the growth of R, semi-annual variation appears against a background of annual variation, in the form of second peaks (maximum in June). At observatories located in low and middle latitudes, second peaks become more appreciable with an increase of R (March-April and September-October). During the periods of low solar activity, they are insignificant. This work has been carried out with the support from International Scientific and Technology Center (Project #KR-214).

A retrospective analysis of rectal and bladder dose for gynecological brachytherapy treatments with GZP6 HDR afterloading system.

PubMed

Bahreyni Toossi, Mohammad Taghi; Ghorbani, Mahdi; Makhdoumi, Yasha; Taheri, Mojtaba; Homaee Shandiz, Fatemeh; Zahed Anaraki, Siavash; Soleimani Meigooni, Ali

2012-01-01

The aim of this work is to evaluate rectal and bladder dose for the patients treated for gynecological cancers. The GZP6 high dose rate brachytherapy system has been recently introduced to a number of radiation therapy departments in Iran, for treatment of various tumor sites such as cervix and vagina. Our analysis was based on dose measurements for 40 insertions in 28 patients, treated by a GZP6 unit between June 2009 and November 2010. Treatments consisted of combined teletherapy and intracavitary brachytherapy. In vivo dosimetry was performed with TLD-400 chips and TLD-100 microcubes in the rectum and bladder. The average of maximum rectal and bladder dose values were found to be 7.62 Gy (range 1.72-18.55 Gy) and 5.17 Gy (range 0.72-15.85 Gy), respectively. It has been recommended by the ICRU that the maximum dose to the rectum and bladder in intracavitary treatment of vaginal or cervical cancer should be lower than 80% of the prescribed dose to point A in the Manchester system. In this study, of the total number of 40 insertions, maximum rectal dose in 29 insertions (72.5% of treatment sessions) and maximum bladder dose in 18 insertions (45% of treatments sessions) were higher than 80% of the prescribed dose to the point of dose prescription. In vivo dosimetry for patients undergoing treatment by GZP6 brachytherapy system can be used for evaluation of the quality of brachytherapy treatments by this system. This information could be used as a base for developing the strategy for treatment of patients treated with GZP6 system.

A retrospective analysis of rectal and bladder dose for gynecological brachytherapy treatments with GZP6 HDR afterloading system

PubMed Central

Bahreyni Toossi, Mohammad Taghi; Ghorbani, Mahdi; Makhdoumi, Yasha; Taheri, Mojtaba; Homaee Shandiz, Fatemeh; Zahed Anaraki, Siavash; Soleimani Meigooni, Ali

2012-01-01

Aim The aim of this work is to evaluate rectal and bladder dose for the patients treated for gynecological cancers. Background The GZP6 high dose rate brachytherapy system has been recently introduced to a number of radiation therapy departments in Iran, for treatment of various tumor sites such as cervix and vagina. Materials and methods Our analysis was based on dose measurements for 40 insertions in 28 patients, treated by a GZP6 unit between June 2009 and November 2010. Treatments consisted of combined teletherapy and intracavitary brachytherapy. In vivo dosimetry was performed with TLD-400 chips and TLD-100 microcubes in the rectum and bladder. Results The average of maximum rectal and bladder dose values were found to be 7.62 Gy (range 1.72–18.55 Gy) and 5.17 Gy (range 0.72–15.85 Gy), respectively. It has been recommended by the ICRU that the maximum dose to the rectum and bladder in intracavitary treatment of vaginal or cervical cancer should be lower than 80% of the prescribed dose to point A in the Manchester system. In this study, of the total number of 40 insertions, maximum rectal dose in 29 insertions (72.5% of treatment sessions) and maximum bladder dose in 18 insertions (45% of treatments sessions) were higher than 80% of the prescribed dose to the point of dose prescription. Conclusion In vivo dosimetry for patients undergoing treatment by GZP6 brachytherapy system can be used for evaluation of the quality of brachytherapy treatments by this system. This information could be used as a base for developing the strategy for treatment of patients treated with GZP6 system. PMID:24377037

Cosmic radiation exposure of biological test systems during the EXPOSE-E mission.

PubMed

Berger, Thomas; Hajek, Michael; Bilski, Pawel; Körner, Christine; Vanhavere, Filip; Reitz, Günther

2012-05-01

In the frame of the EXPOSE-E mission on the Columbus external payload facility EuTEF on board the International Space Station, passive thermoluminescence dosimeters were applied to measure the radiation exposure of biological samples. The detectors were located either as stacks next to biological specimens to determine the depth dose distribution or beneath the sample carriers to determine the dose levels for maximum shielding. The maximum mission dose measured in the upper layer of the depth dose part of the experiment amounted to 238±10 mGy, which relates to an average dose rate of 408±16 μGy/d. In these stacks of about 8 mm height, the dose decreased by 5-12% with depth. The maximum dose measured beneath the sample carriers was 215±16 mGy, which amounts to an average dose rate of 368±27 μGy/d. These values are close to those assessed for the interior of the Columbus module and demonstrate the high shielding of the biological experiments within the EXPOSE-E facility. Besides the shielding by the EXPOSE-E hardware itself, additional shielding was experienced by the external structures adjacent to EXPOSE-E, such as EuTEF and Columbus. This led to a dose gradient over the entire exposure area, from 215±16 mGy for the lowest to 121±6 mGy for maximum shielding. Hence, the doses perceived by the biological samples inside EXPOSE-E varied by 70% (from lowest to highest dose). As a consequence of the high shielding, the biological samples were predominantly exposed to galactic cosmic heavy ions, while electrons and a significant fraction of protons of the radiation belts and solar wind did not reach the samples.

Estimation of the collective ionizing dose in the Portuguese population for the years 2011 and 2012, due to nuclear medicine exams.

PubMed

Costa, F; Teles, P; Nogueira, A; Barreto, A; Santos, A I; Carvalho, A; Martins, B; Oliveira, C; Gaspar, C; Barros, C; Neves, D; Costa, D; Rodrigues, E; Godinho, F; Alves, F; Cardoso, G; Cantinho, G; Conde, I; Vale, J; Santos, J; Isidoro, J; Pereira, J; Salgado, L; Rézio, M; Vieira, M; Simãozinho, P; Almeida, P; Castro, R; Parafita, R; Pintão, S; Lúcio, T; Reis, T; Vaz, P

2015-01-01

In 2009-2010 a Portuguese consortium was created to implement the methodologies proposed by the Dose Datamed II (DDM2) project, aiming to collect data from diagnostic X-ray and nuclear medicine (NM) procedures, in order to determine the most frequently prescribed exams and the associated ionizing radiation doses for the Portuguese population. The current study is the continuation of this work, although it focuses only on NM exams for the years 2011 and 2012. The annual frequency of each of the 28 selected NM exams and the average administered activity per procedure was obtained by means of a nationwide survey sent to the 35 NM centres in Portugal. The results show a reduction of the number of cardiac exams performed in the last two years compared with 2010, leading to a reduction of the annual average effective dose of Portuguese population due to NM exams from 0.08 mSv ± 0.017 mSv/caput to 0.059 ± 0.011 mSv/caput in 2011 and 0.054 ± 0.011 mSv/caput in 2012. Portuguese total annual average collective effective dose due to medical procedures was estimated to be 625.6 ± 110.9 manSv in 2011 and 565.1 ± 117.3 manSv in 2012, a reduction in comparison with 2010 (840.3 ± 183.8 manSv). The most frequent exams and the ones that contributed the most for total population dose were the cardiac and bone exams, although a decrease observed in 2011 and in 2012 was verified. The authors intend to perform this study periodically to identify trends in the annual Portuguese average effective dose and to help to raise awareness about the potential dose optimization. Copyright © 2014 Elsevier España, S.L.U. and SEMNIM. All rights reserved.

Monitoring and assessment of radionuclide discharges from Temelín Nuclear Power Plant into the Vltava River (Czech Republic).

PubMed

Hanslík, Eduard; Ivanovová, Diana; Juranová, Eva; Simonek, Pavel; Jedináková-Krízová, Vĕra

2009-02-01

The paper summarizes impacts of the Temelín Nuclear Power Plant (NPP) on the Vltava and Labe River basins. The study is based on the results of long-term monitoring carried out before the plant operation (1989-2000), and subsequently during the plant operation (2001-2005). In the first period, the main objective was to determine background radionuclide levels remaining in the environment after global fallout and due to the Chernobyl accident. A decrease in the concentrations of (90)Sr, (134)Cs and (137)Cs, which was observed before the plant operation, continued also during the subsequent period. Apart from tritium, the results of the observation did not indicate any impacts of the plant on the concentrations of activation and fission products in the hydrosphere. The annual average tritium concentrations in the Vltava River were in agreement with predicted values. The maximum annual average tritium concentration (13.5 Bq L(-1)) was observed in 2004 downstream from the wastewater discharge in the Vltava River at Solenice. Estimated radiation doses for adults due to intakes of river water as drinking water contaminated by tritium are below 0.1 microSv y(-1).

The Northern Marshall Islands Radiological Survey: data and dose assessments.

PubMed

Robison, W L; Noshkin, V E; Conrado, C L; Eagle, R J; Brunk, J L; Jokela, T A; Mount, M E; Phillips, W A; Stoker, A C; Stuart, M L; Wong, K M

1997-07-01

Fallout from atmospheric nuclear tests, especially from those conducted at the Pacific Proving Grounds between 1946 and 1958, contaminated areas of the Northern Marshall Islands. A radiological survey at some Northern Marshall Islands was conducted from September through November 1978 to evaluate the extent of residual radioactive contamination. The atolls included in the Northern Marshall Islands Radiological Survey (NMIRS) were Likiep, Ailuk, Utirik, Wotho, Ujelang, Taka, Rongelap, Rongerik, Bikar, Ailinginae, and Mejit and Jemo Islands. The original test sites, Bikini and Enewetak Atolls, were also visited on the survey. An aerial survey was conducted to determine the external gamma exposure rate. Terrestrial (soil, food crops, animals, and native vegetation), cistern and well water samples, and marine (sediment, seawater, fish and clams) samples were collected to evaluate radionuclide concentrations in the atoll environment. Samples were processed and analyzed for 137Cs, 90Sr, 239+240Pu and 241Am. The dose from the ingestion pathway was calculated using the radionuclide concentration data and a diet model for local food, marine, and water consumption. The ingestion pathway contributes 70% to 90% of the estimated dose. Approximately 95% of the dose is from 137Cs. 90Sr is the second most significant radionuclide via ingestion. External gamma exposure from 137Cs accounts for about 10% to 30% of the dose. 239+240Pu and 241Am are the major contributors to dose via the inhalation pathway; however, inhalation accounts for only about 1% of the total estimated dose, based on surface soil levels and resuspension studies. All doses are computed for concentrations decay corrected to 1996. The maximum annual effective dose from manmade radionuclides at these atolls ranges from .02 mSv y(-1) to 2.1 mSv y(-1). The background dose in the Marshall Islands is estimated to be 2.4 mSv y(-1). The combined dose from both background and bomb related radionuclides ranges from slightly over 2.4 mSv y(-1) to 4.5 mSv y(-1). The 50-y integral dose ranges from 0.5 to 65 mSv.

Assessment of the occupational eye lens dose for clinical staff in interventional radiology, cardiology and neuroradiology.

PubMed

Omar, Artur; Kadesjö, Nils; Palmgren, Charlotta; Marteinsdottir, Maria; Segerdahl, Tony; Fransson, Annette

2017-03-20

In accordance with recommendations by the International Commission on Radiological Protection, the current European Basic Safety Standards has adopted a reduced occupational eye lens dose limit of 20 mSv yr -1 . The radiation safety implications of this dose limit is of concern for clinical staff that work with relatively high dose x-ray angiography and interventional radiology. Presented in this work is a thorough assessment of the occupational eye lens dose based on clinical measurements with active personal dosimeters worn by staff during various types of procedures in interventional radiology, cardiology and neuroradiology. Results are presented in terms of the estimated equivalent eye lens dose for various medical professions. In order to compare the risk of exceeding the regulatory annual eye lens dose limit for the widely different clinical situations investigated in this work, the different medical professions were separated into categories based on their distinct work pattern: staff that work (a) regularly beside the patient, (b) in proximity to the patient and (c) typically at a distance from the patient. The results demonstrate that the risk of exceeding the annual eye lens dose limit is of concern for staff category (a), i.e. mainly the primary radiologist/cardiologist. However, the results also demonstrate that the risk can be greatly mitigated if radiation protection shields are used in the clinical routine. The results presented in this work cover a wide range of clinical situations, and can be used as a first indication of the risk of exceeding the annual eye lens dose limit for staff at other medical centres.

Ingestion dose from 238U, 232Th, 226Ra, 40K and 137Cs in cereals, pulses and drinking water to adult population in a high background radiation area, Odisha, India.

PubMed

Lenka, Pradyumna; Sahoo, S K; Mohapatra, S; Patra, A C; Dubey, J S; Vidyasagar, D; Tripathi, R M; Puranik, V D

2013-03-01

A natural high background radiation area is located in Chhatrapur, Odisha in the eastern part of India. The inhabitants of this area are exposed to external radiation levels higher than the global average background values, due to the presence of uranium, thorium and its decay products in the monazite sands bearing placer deposits in its beaches. The concentrations of (232)Th, (238)U, (226)Ra, (40)K and (137)Cs were determined in cereals (rice and wheat), pulses and drinking water consumed by the population residing around this region and the corresponding annual ingestion dose was calculated. The annual ingestion doses from cereals, pulses and drinking water varied in the range of 109.4-936.8, 10.2-307.5 and 0.5-2.8 µSv y(-1), respectively. The estimated total annual average effective dose due to the ingestion of these radionuclides in cereals, pulses and drinking water was 530 µSv y(-1). The ingestion dose from cereals was the highest mainly due to a high consumption rate. The highest contribution of dose was found to be from (226)Ra for cereals and drinking water and (40)K was the major dose contributor from the intake of pulses. The contribution of man-made radionuclide (137)Cs to the total dose was found to be minimum. (226)Ra was found to be the largest contributor to ingestion dose from all sources.

Systematic influences of gamma-ray spectrometry data near the decision threshold for radioactivity measurements in the environment.

PubMed

Zorko, Benjamin; Korun, Matjaž; Mora Canadas, Juan Carlos; Nicoulaud-Gouin, Valerie; Chyly, Pavol; Blixt Buhr, Anna Maria; Lager, Charlotte; Aquilonius, Karin; Krajewski, Pawel

2016-07-01

Several methods for reporting outcomes of gamma-ray spectrometric measurements of environmental samples for dose calculations are presented and discussed. The measurement outcomes can be reported as primary measurement results, primary measurement results modified according to the quantification limit, best estimates obtained by the Bayesian posterior (ISO 11929), best estimates obtained by the probability density distribution resembling shifting, and the procedure recommended by the European Commission (EC). The annual dose is calculated from the arithmetic average using any of these five procedures. It was shown that the primary measurement results modified according to the quantification limit could lead to an underestimation of the annual dose. On the other hand the best estimates lead to an overestimation of the annual dose. The annual doses calculated from the measurement outcomes obtained according to the EC's recommended procedure, which does not cope with the uncertainties, fluctuate between an under- and overestimation, depending on the frequency of the measurement results that are larger than the limit of detection. In the extreme case, when no measurement results above the detection limit occur, the average over primary measurement results modified according to the quantification limit underestimates the average over primary measurement results for about 80%. The average over best estimates calculated according the procedure resembling shifting overestimates the average over primary measurement results for 35%, the average obtained by the Bayesian posterior for 85% and the treatment according to the EC recommendation for 89%. Copyright © 2016 Elsevier Ltd. All rights reserved.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ma, C; Lin, M; Chen, L

Purpose: Recent in vitro and in vivo experimental findings provided strong evidence that pulsed low-dose-rate radiotherapy (PLDR) produced equivalent tumor control as conventional radiotherapy with significantly reduced normal tissue toxicities. This work aimed to implement a PLDR clinical protocol for the management of recurrent cancers utilizing IMRT and VMAT. Methods: Our PLDR protocol requires that the daily 2Gy dose be delivered in 0.2Gy×10 pulses with a 3min interval between the pulses. To take advantage of low-dose hyper-radiosensitivity the mean dose to the target is set at 0.2Gy and the maximum dose is limited to 0.4Gy per pulse. Practical planning strategiesmore » were developed for IMRT and VMAT: (1) set 10 ports for IMRT and 10 arcs for VMAT with each angle/arc as a pulse; (2) set the mean dose (0.2Gy) and maximum dose (0.4Gy) to the target per pulse as hard constraints (no constraints to OARs); (3) select optimal port/arc angles to avoid OARs; and (4) use reference structures in or around target/OARs to reduce maximum dose to the target/OARs. IMRT, VMAT and 3DCRT plans were generated for 60 H and N, breast, lung, pancreas and prostate patients and compared. Results: All PLDR treatment plans using IMRT and VMAT met the dosimetry requirements of the PLDR protocol (mean target dose: 0.20Gy±0.01Gy; maximum target dose < 0.4Gy). In comparison with 3DCRT, IMRT and VMAT exhibited improved target dose conformity and OAR dose sparing. A single arc can minimize the difference in the target dose due to multi-angle incidence although the delivery time is longer than 3DCRT and IMRT. Conclusion: IMRT and VMAT are better modalities for PLDR treatment of recurrent cancers with superior target dose conformity and critical structure sparing. The planning strategies/guidelines developed in this work are practical for IMRT/VMAT treatment planning to meet the dosimetry requirements of the PLDR protocol.« less

Survey of Occupational Noise Exposure in CF Personnel in Selected High-Risk Trades

DTIC Science & Technology

2003-11-01

peak, maximum level , minimum level , average sound level , time weighted average, dose, projected 8-hour dose, and upper limit time were measured for...10 4.4.2 Maximum Sound Level ...11 4.4.3 Minimum Sound Level

Health and ecological hazards due to natural radioactivity in soil from mining areas of Nasarawa State, Nigeria.

PubMed

Aliyu, Abubakar Sadiq; Ibrahim, Umar; Akpa, Chidozie Timothy; Garba, Nuraddeen Nasiru; Ramli, Ahmad Termizi

2015-01-01

Nasarawa State is located in north central Nigeria and it is known as Nigeria's home of solid minerals. It is endowed with barite, copper, zinc, tantalite and granite. Continuous releases of mining waste and tailings into the biosphere may result in a build-up of radionuclides in air, water and soil. This work therefore aims to measure the activity concentration levels of primordial radionuclides in the soil/sediment samples collected from selected mines of the mining areas of Nasarawa State. The paper also assesses the radiological and radio ecological impacts of mining activities on the residents of mining areas and their environment. The activity concentrations of primordial radionuclides ((226)Ra, (232)Th and (40)K) in the surface soils/sediment samples were determined using sodium iodide-thallium gamma spectroscopy. Seven major mines were considered with 21 samples taken from each of the mines for radiochemistry analysis. The human health hazard assessment was conducted using regulatory methodologies set by the United Nations Scientific Committee on the Effects of Atomic Radiation, while the radio ecological impact assessment was conducted using the ERICA tool v. 1.2. The result shows that the activity concentrations of (40)K in the water ways of the Akiri copper and the Azara barite mines are 60 and 67% higher than the world average value for (40)K, respectively. In all mines, the annual effective dose rates (mSv y(-1)) were less than unity, and a maximum annual gonadal dose of 0.58 mSv y(-1) is received at the Akiri copper mine, which is almost twice the world average value for gonadal dose. The external hazard indices for all the mines were less than unity. Our results also show that mollusc-gastropod, insect larvae, mollusc-bivalve and zooplankton are the freshwater biotas with the highest dose rates ranging from 5 to 7 µGy h(-1). These higher dose rates could be associated with zinc and copper mining at Abuni and Akiri, respectively. The most exposed terrestrial reference organisms are lichen and bryophytes. In all cases, the radio ecological risks are not likely to be discernible. This paper presents a pioneer data for ecological risk from ionizing contaminants due to mining activity in Nasarawa State, Nigeria. Its methodology could be adopted for future work on radioecology of mining.

Electron fluence correction factors for various materials in clinical electron beams.

PubMed

Olivares, M; DeBlois, F; Podgorsak, E B; Seuntjens, J P

2001-08-01

Relative to solid water, electron fluence correction factors at the depth of dose maximum in bone, lung, aluminum, and copper for nominal electron beam energies of 9 MeV and 15 MeV of the Clinac 18 accelerator have been determined experimentally and by Monte Carlo calculation. Thermoluminescent dosimeters were used to measure depth doses in these materials. The measured relative dose at dmax in the various materials versus that of solid water, when irradiated with the same number of monitor units, has been used to calculate the ratio of electron fluence for the various materials to that of solid water. The beams of the Clinac 18 were fully characterized using the EGS4/BEAM system. EGSnrc with the relativistic spin option turned on was used to optimize the primary electron energy at the exit window, and to calculate depth doses in the five phantom materials using the optimized phase-space data. Normalizing all depth doses to the dose maximum in solid water stopping power ratio corrected, measured depth doses and calculated depth doses differ by less than +/- 1% at the depth of dose maximum and by less than 4% elsewhere. Monte Carlo calculated ratios of doses in each material to dose in LiF were used to convert the TLD measurements at the dose maximum into dose at the center of the TLD in the phantom material. Fluence perturbation correction factors for a LiF TLD at the depth of dose maximum deduced from these calculations amount to less than 1% for 0.15 mm thick TLDs in low Z materials and are between 1% and 3% for TLDs in Al and Cu phantoms. Electron fluence ratios of the studied materials relative to solid water vary between 0.83+/-0.01 and 1.55+/-0.02 for materials varying in density from 0.27 g/cm3 (lung) to 8.96 g/cm3 (Cu). The difference in electron fluence ratios derived from measurements and calculations ranges from -1.6% to +0.2% at 9 MeV and from -1.9% to +0.2% at 15 MeV and is not significant at the 1sigma level. Excluding the data for Cu, electron fluence correction factors for open electron beams are approximately proportional to the electron density of the phantom material and only weakly dependent on electron beam energy.

Trends in precipitation, streamflow, reservoir pool elevations, and reservoir releases in Arkansas and selected sites in Louisiana, Missouri, and Oklahoma, 1951–2011

USGS Publications Warehouse

Wagner, Daniel M.; Krieger, Joshua D.; Merriman, Katherine R.

2014-01-01

The U.S. Geological Survey (USGS) and the U.S. Army Corps of Engineers (USACE) conducted a statistical analysis of trends in precipitation, streamflow, reservoir pool elevations, and reservoir releases in Arkansas and selected sites in Louisiana, Missouri, and Oklahoma for the period 1951–2011. The Mann-Kendall test was used to test for trends in annual and seasonal precipitation, annual and seasonal streamflows of 42 continuous-record USGS streamflow-gaging stations, annual pool elevations and releases from 16 USACE reservoirs, and annual releases from 11 dams on the Arkansas River. A statistically significant (p≤0.10) upward trend was observed in annual precipitation for the State, with a Sen slope of approximately 0.10 inch per year. Autumn and winter were the only seasons that had statistically significant trends in precipitation. Five of six physiographic sections and six of seven 4-digit hydrologic unit code (HUC) regions in Arkansas had statistically significant upward trends in autumn precipitation, with Sen slopes of approximately 0.06 to 0.10 inch per year. Sixteen sites had statistically significant upward trends in the annual mean daily streamflow and were located on streams that drained regions with statistically significant upward trends in annual precipitation. Expected annual rates of change corresponding to statistically significant trends in annual mean daily streamflows, which ranged from 0.32 to 0.88 percent, were greater than those corresponding to regions with statistically significant upward trends in annual precipitation, which ranged from 0.19 to 0.28 percent, suggesting that the observed trends in regional annual precipitation do not fully account for the observed trends in annual mean daily streamflows. Trends in annual maximum daily streamflows were similar to trends in the annual mean daily streamflows but were only statistically significant at seven sites. There were more statistically significant trends (28 of 42 sites) in the annual minimum daily streamflows than in the annual means or maximums. Statistically significant trends in the annual minimum daily streamflows were upward at 18 sites and downward at 10 sites. Despite autumn being the only season that had statistically significant upward trends in seasonal precipitation, statistically significant upward trends in seasonal mean streamflows occurred in every season but spring. Trends in the annual mean, maximum, and minimum daily pool elevations of USACE reservoirs were consistent between metrics for reservoirs in the White, Arkansas, and Ouachita River watersheds, while trends varied between metrics at DeQueen Lake, Millwood Lake, and Lake Chicot. Most of the statistically significant trends in pool elevation metrics were upward and gradual—Sen slopes were less than 0.37 foot per year—and were likely the result of changes in reservoir regulation plans. Trends in the annual mean and maximum daily releases from USACE reservoirs were generally upward in all HUC regions. There were few statistically significant trends in the annual mean daily releases because the reservoirs are operated to maintain a regulation stage at a downstream site according to guidelines set forth in the regulation plans of the reservoirs. The annual number of low-flow days was both increasing and decreasing for reservoirs in northern Arkansas and southern Missouri and generally increasing for reservoirs in southern Arkansas.

A Phase I study of bizelesin (NSC 615291) in patients with advanced solid tumors.

PubMed

Pitot, Henry C; Reid, Joel M; Sloan, Jeff A; Ames, Matthew M; Adjei, Alex A; Rubin, Joseph; Bagniewski, Pamela G; Atherton, Pamela; Rayson, Daniel; Goldberg, Richard M; Erlichman, Charles

2002-03-01

To evaluate the toxicities, characterize the pharmacokinetics, and determine the maximum-tolerated dose of bizelesin administered once every 4 weeks. Patients with advanced solid tumors received escalating doses of bizelesin as an i.v. push every 4 weeks. Pharmacokinetic studies were performed with the first treatment cycle. Nineteen eligible patients received a total of 54 courses of bizelesin at doses ranging from 0.1 to 1 microg/m(2). Dose-limiting toxicity of neutropenia was seen in 2 of 4 patients treated at the 1 microg/m(2) dose level. Nonhematological toxicity was generally mild with maximum toxicity being

Eye lens exposure to medical staff during endoscopic retrograde cholangiopancreatography.

PubMed

Zagorska, A; Romanova, K; Hristova-Popova, J; Vassileva, J; Katzarov, K

2015-11-01

The paper presents a study of the radiation doses to eye lens of medical staff during endoscopic retrograde cholangiopancreatography (ERCP) procedures performed in a busy gastroenterology department. For each procedure the dose equivalent to the eye, exposure time, dose rate, Kerma Area Product and fluoroscopy time were recorded. Measurements were performed for a period of two months in four main positions of the operating staff, and then extrapolated to estimate annual doses. The fluoroscopy time per ERCP procedure varied between 1.0 min and 28.8 min, with a mean value of 4.6 min. The calculated mean eye dose per procedure varied between 34.9 μSv and 93.3 μSv. The results demonstrated that if eye protection is not used, annual doses to the eye lens of the gastroenterologist performing the procedure and the anesthesiologist can exceed the dose limit of 20 mSv per year. Copyright © 2015 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.

COMPREHENSIVE DATA CONCERNING COSMIC RADIATION DOSES AT GROUND LEVEL AND IN-FLIGHTS FOR TURKEY.

PubMed

Parmaksız, A

2016-12-01

Cosmic radiation doses of individuals living in 81 cities in Turkey were estimated by using CARI-6 software. Annual cosmic radiation doses of individuals were found to be between 308 and 736 µSv y -1 at ground level. The population-weighted annual effective dose from cosmic radiation was determined to be 387 µSv y -1 for Turkey. Cosmic radiation doses on-board for 137 (60 domestic and 77 international) flights varied from 1.2 to 83 µSv. It was estimated that six or over long-route round-trip air travels may cause cosmic radiation dose above the permissible limit for member of the public, i.e. 1 mSv y -1 According to the assumption of flights throughout 800 h on each route, cosmic radiation doses were found to be between 1.0 and 4.8 mSv for aircrew. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Solar UV-A and UV-B radiation fluxes at two Alpine stations at different altitudes

NASA Astrophysics Data System (ADS)

Blumthaler, M.; Ambach, W.; Rehwald, W.

1992-03-01

Daily totals of UV-A and UV-B radiation fluxes and global radiation were measured since 1981 at Jungfraujoch (3576 m) a.s.l.) and in Innsbruck (577 m a.s.l.) in their seasonal course. The altitude effect of annual totals yields 19%/1000 m (UV-B), 11%/1000 m (UV-A) and 9%/1000 m (global radiation) with reference to Innsbruck station. The ratio of the daily totals of UV-B/global radiation shows a significant seasonal course with the maximum in summer, whereas the ratio of the daily totals of UV-A/global radiation shows no significant seasonal variation. The biological effective doses of erythema reaction, delayed tanning and immediate tanning by UV-A and UV-B radiant exposure are reported in the seasonal course at Jungfraujoch and in Innsbruck.

Role of step size and max dwell time in anatomy based inverse optimization for prostate implants

PubMed Central

Manikandan, Arjunan; Sarkar, Biplab; Rajendran, Vivek Thirupathur; King, Paul R.; Sresty, N.V. Madhusudhana; Holla, Ragavendra; Kotur, Sachin; Nadendla, Sujatha

2013-01-01

In high dose rate (HDR) brachytherapy, the source dwell times and dwell positions are vital parameters in achieving a desirable implant dose distribution. Inverse treatment planning requires an optimal choice of these parameters to achieve the desired target coverage with the lowest achievable dose to the organs at risk (OAR). This study was designed to evaluate the optimum source step size and maximum source dwell time for prostate brachytherapy implants using an Ir-192 source. In total, one hundred inverse treatment plans were generated for the four patients included in this study. Twenty-five treatment plans were created for each patient by varying the step size and maximum source dwell time during anatomy-based, inverse-planned optimization. Other relevant treatment planning parameters were kept constant, including the dose constraints and source dwell positions. Each plan was evaluated for target coverage, urethral and rectal dose sparing, treatment time, relative target dose homogeneity, and nonuniformity ratio. The plans with 0.5 cm step size were seen to have clinically acceptable tumor coverage, minimal normal structure doses, and minimum treatment time as compared with the other step sizes. The target coverage for this step size is 87% of the prescription dose, while the urethral and maximum rectal doses were 107.3 and 68.7%, respectively. No appreciable difference in plan quality was observed with variation in maximum source dwell time. The step size plays a significant role in plan optimization for prostate implants. Our study supports use of a 0.5 cm step size for prostate implants. PMID:24049323

Effect of the Maximum Dose on White Matter Fiber Bundles Using Longitudinal Diffusion Tensor Imaging

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhu, Tong; Chapman, Christopher H.; Tsien, Christina

2016-11-01

Purpose: Previous efforts to decrease neurocognitive effects of radiation focused on sparing isolated cortical structures. We hypothesize that understanding temporal, spatial, and dosimetric patterns of radiation damage to whole-brain white matter (WM) after partial-brain irradiation might also be important. Therefore, we carried out a study to develop the methodology to assess radiation therapy (RT)–induced damage to whole-brain WM bundles. Methods and Materials: An atlas-based, automated WM tractography analysis was implemented to quantify longitudinal changes in indices of diffusion tensor imaging (DTI) of 22 major WM fibers in 33 patients with predominantly low-grade or benign brain tumors treated by RT. Sixmore » DTI scans per patient were performed from before RT to 18 months after RT. The DTI indices and planned doses (maximum and mean doses) were mapped onto profiles of each of 22 WM bundles. A multivariate linear regression was performed to determine the main dose effect as well as the influence of other clinical factors on longitudinal percentage changes in axial diffusivity (AD) and radial diffusivity (RD) from before RT. Results: Among 22 fiber bundles, AD or RD changes in 12 bundles were affected significantly by doses (P<.05), as the effect was progressive over time. In 9 elongated tracts, decreased AD or RD was significantly related to maximum doses received, consistent with a serial structure. In individual bundles, AD changes were up to 11.5% at the maximum dose locations 18 months after RT. The dose effect on WM was greater in older female patients than younger male patients. Conclusions: Our study demonstrates for the first time that the maximum dose to the elongated WM bundles causes post-RT damage in WM. Validation and correlative studies are necessary to determine the ability and impact of sparing these bundles on preserving neurocognitive function after RT.« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

Small, Katherine; Kelly, Chris; Beldham-Collins, Rachael

A comparative study was conducted comparing the difference between (1) conformal radiotherapy (CRT) to the whole breast with sequential boost excision cavity plans and (2) intensity-modulated radiation therapy (IMRT) to the whole breast with simultaneously integrated boost to the excision cavity. The computed tomography (CT) data sets of 25 breast cancer patients were used and the results analysed to determine if either planning method produced superior plans. CT data sets from 25 past breast cancer patients were planned using (1) CRT prescribed to 50 Gy in 25 fractions (Fx) to the whole-breast planning target volume (PTV) and 10 Gy inmore » 5Fx to the excision cavity and (2) IMRT prescribed to 60 Gy in 25Fx, with 60 Gy delivered to the excision cavity PTV and 50 Gy delivered to the whole-breast PTV, treated simultaneously. In total, 50 plans were created, with each plan evaluated by PTV coverage using conformity indices, plan maximum dose, lung dose, and heart maximum dose for patients with left-side lesions. CRT plans delivered the lowest plan maximum doses in 56% of cases (average CRT = 6314.34 cGy, IMRT = 6371.52 cGy). They also delivered the lowest mean lung dose in 68% of cases (average CRT = 1206.64 cGy, IMRT = 1288.37 cGy) and V20 in 88% of cases (average CRT = 20.03%, IMRT = 21.73%) and V30 doses in 92% of cases (average CRT = 16.82%, IMRT = 17.97%). IMRT created more conformal plans, using both conformity index and conformation number, in every instance, and lower heart maximum doses in 78.6% of cases (average CRT = 5295.26 cGy, IMRT = 5209.87 cGy). IMRT plans produced superior dose conformity and shorter treatment duration, but a slightly higher planning maximum and increased lung doses. IMRT plans are also faster to treat on a daily basis, with shorter fractionation.« less

Statistical summaries of streamflow data for selected gaging stations on and near the Idaho National Engineering Laboratory, Idaho, through September 1990

USGS Publications Warehouse

Stone, M.A.J.; Mann, Larry J.; Kjelstrom, L.C.

1993-01-01

Statistical summaries and graphs of streamflow data were prepared for 13 gaging stations with 5 or more years of continuous record on and near the Idaho National Engineering Laboratory. Statistical summaries of streamflow data for the Big and Little Lost Rivers and Birch Creek were analyzed as a requisite for a comprehensive evaluation of the potential for flooding of facilities at the Idaho National Engineering Laboratory. The type of statistical analyses performed depended on the length of streamflow record for a gaging station. Streamflow statistics generated for stations with 5 to 9 years of record were: (1) magnitudes of monthly and annual flows; (2) duration of daily mean flows; and (3) maximum, median, and minimum daily mean flows. Streamflow statistics generated for stations with 10 or more years of record were: (1) magnitudes of monthly and annual flows; (2) magnitudes and frequencies of daily low, high, instantaneous peak (flood frequency), and annual mean flows; (3) duration of daily mean flows; (4) exceedance probabilities of annual low, high, instantaneous peak, and mean annual flows; (5) maximum, median, and minimum daily mean flows; and (6) annual mean and mean annual flows.

“Hallucinations” Following Acute Cannabis Dosing: A Case Report and Comparison to Other Hallucinogenic Drugs

PubMed Central

Barrett, Frederick S.; Schlienz, Nicolas J.; Lembeck, Natalie; Waqas, Muhammad; Vandrey, Ryan

2018-01-01

Abstract Introduction: Cannabis has been historically classified as a hallucinogen. However, subjective cannabis effects do not typically include hallucinogen-like effects. Empirical reports of hallucinogen-like effects produced by cannabis in controlled settings, particularly among healthy research volunteers, are rare and have mostly occurred after administration of purified Δ-9 tetrahydrocannabinol (THC) rather than whole plant cannabis. Methods: The case of a healthy 30-year-old male who experienced auditory and visual hallucinations in a controlled laboratory study after inhaling vaporized cannabis that contained 25 mg THC (case dose) is presented. Ratings on the Hallucinogen Rating Scale (HRS) following the case dose are compared with HRS ratings obtained from the participant after other doses of cannabis and with archival HRS data from laboratory studies involving acute doses of cannabis, psilocybin, dextromethorphan (DXM), and salvinorin A. Results: Scores on the Volition subscale of the HRS were greater for the case dose than for the maximum dose administered in any other comparison study. Scores on the Intensity and Perception subscales were greater for the case dose than for the maximum dose of cannabis, psilocybin, or salvinorin A. Scores on the Somaesthesia subscale were greater for the case dose than for the maximum dose of DXM, salvinorin A, or cannabis. Scores on the Affect and Cognition subscales for the case dose were significantly lower than for the maximum doses of psilocybin and DXM. Conclusion: Acute cannabis exposure in a healthy adult male resulted in self-reported hallucinations that rated high in magnitude on several subscales of the HRS. However, the hallucinatory experience in this case was qualitatively different than that typically experienced by participants receiving classic and atypical hallucinogens, suggesting that the hallucinatory effects of cannabis may have a unique pharmacological mechanism of action. This type of adverse event needs to be considered in the clinical use of cannabis. PMID:29682608

The use of paracetamol (acetaminophen) among a community sample of people with chronic non-cancer pain prescribed opioids.

PubMed

Hoban, B; Larance, B; Gisev, N; Nielsen, S; Cohen, M; Bruno, R; Shand, F; Lintzeris, N; Hall, W; Farrell, M; Degenhardt, L

2015-11-01

The regular use of simple analgesics in addition to opioids such as paracetamol (or acetaminophen) is recommended for persistent pain to enhance analgesia. Few studies have examined the frequency and doses of paracetamol among people with chronic non-cancer pain including use above the recommended maximum daily dose. To assess (i) the prevalence of paracetamol use among people with chronic non-cancer pain prescribed opioids, (ii) assess the prevalence of paracetamol use above the recommended maximum daily dose and (iii) assess correlates of people who used paracetamol above the recommended maximum daily dose including: age, gender, income, education, pain severity and interference, use of paracetamol/opioid combination analgesics, total opioid dose, depression, anxiety, pain self-efficacy or comorbid substance use, among people prescribed opioids for chronic non-cancer pain. This study draws on baseline data collected for the Pain and Opioids IN Treatment (POINT) study and utilises data from 962 interviews and medication diaries. The POINT study is national prospective cohort of people with chronic non-cancer pain prescribed opioids. Participants were recruited from randomly selected pharmacies across Australia. Sixty-three per cent of the participants had used paracetamol in the past week (95% CI = 59.7-65.8). Among the paracetamol users 22% (95% CI = 19.3-24.6) had used paracetamol/opioid combination analgesics and 4.8% (95% CI = 3.6-6.3) had used paracetamol above the recommended maximum daily dose (i.e. > 4000 mg/day). Following binomial logistic regression (χ(2) = 25.98, df = 10, p = 0.004), people who had taken above the recommended maximum daily dose were less likely to have low income (AOR = 0.52, 95% CI = 0.27-0.99), more likely to use paracetamol/opioid combination analgesics (AOR = 2.01, 95% CI = 1.02-3.98) and more likely to take a higher opioid dose (AOR = 1.00, 95% CI = 1.00-1.01). The majority of people with chronic non-cancer pain prescribed opioids report using paracetamol appropriately. High income, use of paracetamol/opioid combination analgesics and higher opioid dose were independently associated with paracetamol use above the recommended maximum daily dose. © 2015 John Wiley & Sons Ltd.

Contura Multi-Lumen Balloon breast brachytherapy catheter: comparative dosimetric findings of a phase 4 trial.

PubMed

Arthur, Douglas W; Vicini, Frank A; Todor, Dorin A; Julian, Thomas B; Cuttino, Laurie W; Mukhopadhyay, Nitai D

2013-06-01

Final dosimetric findings of a completed, multi-institutional phase 4 registry trial using the Contura Multi-Lumen Balloon (MLB) breast brachytherapy catheter to deliver accelerated partial breast irradiation (APBI) in patients with early-stage breast cancer are presented. Three dosimetric plans with identical target coverage were generated for each patient for comparison: multilumen multidwell (MLMD); central-lumen multidwell (CLMD); and central-lumen single-dwell (CLSD) loading of the Contura catheter. For this study, a successful treatment plan achieved ideal dosimetric goals and included the following: ≥ 95% of the prescribed dose (PD) covering ≥ 95% of the target volume (TV); maximum skin dose ≤ 125% of the PD; maximum rib dose ≤ 145% of the PD; and V150 ≤50 cc and V200 ≤ 10 cc. Between January 2008 and February 2011, 23 institutions participated. A total of 318 patients were available for dosimetric review. Using the Contura MLB, all dosimetric criteria were met in 78.93% of cases planned with MLMD versus 55.38% with the CLMD versus 37.66% with the CLSD (P ≤.0001). Evaluating all patients with the full range of skin to balloon distance represented, median maximum skin dose was reduced by 12% and median maximum rib dose by 13.9% when using MLMD-based dosimetric plans compared to CLSD. The dosimetric benefit of MLMD was further demonstrated in the subgroup of patients where skin thickness was <5 mm, where MLMD use allowed a 38% reduction in median maximum skin dose over CLSD. For patients with rib distance <5 mm, the median maximum rib dose reduction was 27%. Use of the Contura MLB catheter produced statistically significant improvements in dosimetric capabilities between CLSD and CLMD treatments. This device approach demonstrates the ability not only to overcome the barriers of limited skin thickness and close rib proximity, but to consistently achieve a higher standard of dosimetric planning goals. Copyright © 2013 Elsevier Inc. All rights reserved.

Contura Multi-Lumen Balloon Breast Brachytherapy Catheter: Comparative Dosimetric Findings of a Phase 4 Trial

DOE Office of Scientific and Technical Information (OSTI.GOV)

Arthur, Douglas W., E-mail: darthur@mcvh-vcu.edu; Vicini, Frank A.; Todor, Dorin A.

2013-06-01

Purpose: Final dosimetric findings of a completed, multi-institutional phase 4 registry trial using the Contura Multi-Lumen Balloon (MLB) breast brachytherapy catheter to deliver accelerated partial breast irradiation (APBI) in patients with early-stage breast cancer are presented. Methods and Materials: Three dosimetric plans with identical target coverage were generated for each patient for comparison: multilumen multidwell (MLMD); central-lumen multidwell (CLMD); and central-lumen single-dwell (CLSD) loading of the Contura catheter. For this study, a successful treatment plan achieved ideal dosimetric goals and included the following: ≥95% of the prescribed dose (PD) covering ≥95% of the target volume (TV); maximum skin dose ≤125%more » of the PD; maximum rib dose ≤145% of the PD; and V150 ≤50 cc and V200 ≤10 cc. Results: Between January 2008 and February 2011, 23 institutions participated. A total of 318 patients were available for dosimetric review. Using the Contura MLB, all dosimetric criteria were met in 78.93% of cases planned with MLMD versus 55.38% with the CLMD versus 37.66% with the CLSD (P≤.0001). Evaluating all patients with the full range of skin to balloon distance represented, median maximum skin dose was reduced by 12% and median maximum rib dose by 13.9% when using MLMD-based dosimetric plans compared to CLSD. The dosimetric benefit of MLMD was further demonstrated in the subgroup of patients where skin thickness was <5 mm, where MLMD use allowed a 38% reduction in median maximum skin dose over CLSD. For patients with rib distance <5 mm, the median maximum rib dose reduction was 27%. Conclusions: Use of the Contura MLB catheter produced statistically significant improvements in dosimetric capabilities between CLSD and CLMD treatments. This device approach demonstrates the ability not only to overcome the barriers of limited skin thickness and close rib proximity, but to consistently achieve a higher standard of dosimetric planning goals.« less

Stream gage descriptions and streamflow statistics for sites in the Tigris River and Euphrates River Basins, Iraq

USGS Publications Warehouse

Saleh, Dina K.

2010-01-01

Statistical summaries of streamflow data for all long-term streamflow-gaging stations in the Tigris River and Euphrates River Basins in Iraq are presented in this report. The summaries for each streamflow-gaging station include (1) a station description, (2) a graph showing annual mean discharge for the period of record, (3) a table of extremes and statistics for monthly and annual mean discharge, (4) a graph showing monthly maximum, minimum, and mean discharge, (5) a table of monthly and annual mean discharges for the period of record, (6) a graph showing annual flow duration, (7) a table of monthly and annual flow duration, (8) a table of high-flow frequency data (maximum mean discharge for 3-, 7-, 15-, and 30-day periods for selected exceedance probabilities), and (9) a table of low-flow frequency data (minimum mean discharge for 3-, 7-, 15-, 30-, 60-, 90-, and 183-day periods for selected non-exceedance probabilities).

Streamflow simulation studies of the Hillsborough, Alafia, and Anclote Rivers, west-central Florida

USGS Publications Warehouse

Turner, J.F.

1979-01-01

A modified version of the Georgia Tech Watershed Model was applied for the purpose of flow simulation in three large river basins of west-central Florida. Calibrations were evaluated by comparing the following synthesized and observed data: annual hydrographs for the 1959, 1960, 1973 and 1974 water years, flood hydrographs (maximum daily discharge and flood volume), and long-term annual flood-peak discharges (1950-72). Annual hydrographs, excluding the 1973 water year, were compared using average absolute error in annual runoff and daily flows and correlation coefficients of monthly and daily flows. Correlations coefficients for simulated and observed maximum daily discharges and flood volumes used for calibrating range from 0.91 to 0.98 and average standard errors of estimate range from 18 to 45 percent. Correlation coefficients for simulated and observed annual flood-peak discharges range from 0.60 to 0.74 and average standard errors of estimate range from 33 to 44 percent. (Woodard-USGS)

A Preliminary Performance Assessment for Salt Disposal of High-Level Nuclear Waste - 12173

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lee, Joon H.; Clayton, Daniel; Jove-Colon, Carlos

2012-07-01

A salt repository is one of the four geologic media currently under study by the U.S. DOE Office of Nuclear Energy to support the development of a long-term strategy for geologic disposal of commercial used nuclear fuel (UNF) and high-level radioactive waste (HLW). The immediate goal of the generic salt repository study is to develop the necessary modeling tools to evaluate and improve the understanding of the repository system response and processes relevant to long-term disposal of UNF and HLW in a salt formation. The current phase of this study considers representative geologic settings and features adopted from previous studiesmore » for salt repository sites. For the reference scenario, the brine flow rates in the repository and underlying interbeds are very low, and transport of radionuclides in the transport pathways is dominated by diffusion and greatly retarded by sorption on the interbed filling materials. I-129 is the dominant annual dose contributor at the hypothetical accessible environment, but the calculated mean annual dose is negligibly small. For the human intrusion (or disturbed) scenario, the mean mass release rate and mean annual dose histories are very different from those for the reference scenario. Actinides including Pu-239, Pu-242 and Np-237 are major annual dose contributors, and the calculated peak mean annual dose is acceptably low. A performance assessment model for a generic salt repository has been developed incorporating, where applicable, representative geologic settings and features adopted from literature data for salt repository sites. The conceptual model and scenario for radionuclide release and transport from a salt repository were developed utilizing literature data. The salt GDS model was developed in a probabilistic analysis framework. The preliminary performance analysis for demonstration of model capability is for an isothermal condition at the ambient temperature for the near field. The capability demonstration emphasizes key attributes of a salt repository that are potentially important to the long-term safe disposal of UNF and HLW. The analysis presents and discusses the results showing repository responses to different radionuclide release scenarios (undisturbed and human intrusion). For the reference (or nominal or undisturbed) scenario, the brine flow rates in the repository and underlying interbeds are very low, and transport of radionuclides in the transport pathways is dominated by diffusion and greatly retarded by sorption on the interbed filling materials. I-129 (non-sorbing and unlimited solubility with a very long half-life) is the dominant annual dose contributor at the hypothetical accessible environment, but the calculated mean annual dose is negligibly small that there is no meaningful consequence for the repository performance. For the human intrusion (or disturbed) scenario analysis, the mean mass release rate and mean annual dose histories are very different from those for the reference scenario analysis. Compared to the reference scenario, the relative annual dose contributions by soluble, non-sorbing fission products, particularly I-129, are much lower than by actinides including Pu-239, Pu-242 and Np-237. The lower relative mean annual dose contributions by the fission product radionuclides are due to their lower total inventory available for release (i.e., up to five affected waste packages), and the higher mean annual doses by the actinides are the outcome of the direct release of the radionuclides into the overlying aquifer having high water flow rates, thereby resulting in an early arrival of higher concentrations of the radionuclides at the biosphere drinking water well prior to their significant decay. The salt GDS model analysis has also identified the following future recommendations and/or knowledge gaps to improve and enhance the confidence of the future repository performance analysis. - Repository thermal loading by UNF and HLW, and the effect on the engineered barrier and near-field performance. - Closure and consolidation of salt rocks by creep deformation under the influence of thermal perturbation, and the effect on the engineered barrier and near-field performance. - Brine migration and radionuclide transport under the influence of thermal perturbation in generic salt repository environment, and the effect on the engineered barrier and near-field performance and far-field performance. - Near-field geochemistry and radionuclide mobility in generic salt repository environment (high ionic strength brines, elevated temperatures and chemically reducing condition). - Degradation of engineer barrier components (waste package, waste canister, waste forms, etc.) in a generic salt repository environment (high ionic strength brines, elevated temperatures and chemically reducing condition). - Waste stream types and inventory estimates, particularly for reprocessing high-level waste. (authors)« less

Developing consumer-centered, nonprescription drug labeling a study in acetaminophen.

PubMed

King, Jennifer P; Davis, Terry C; Bailey, Stacy Cooper; Jacobson, Kara L; Hedlund, Laurie A; Di Francesco, Lorenzo; Parker, Ruth M; Wolf, Michael S

2011-06-01

In the U.S., acetaminophen overdose has surpassed viral hepatitis as the leading cause of acute liver failure, and misuse contributes to more than 30,000 hospitalizations annually. Half to two thirds of acetaminophen overdoses are unintentional, suggesting the root cause is likely poor understanding of medication labeling or failure to recognize the consequences of exceeding the recommended maximum daily dosage. Elicit subject feedback about active ingredient and dosing information on over-the-counter (OTC) acetaminophen and elicit feedback on proposed plain-language text and icons. Six focus groups, preceded by individual interviews, were conducted in April 2010 among 45 adults in two cities from two clinics and an adult basic education center. The individual interviews evaluated knowledge of OTC pain relievers, attention to product label information and literacy level while the group discussion elicited preference for label messages and icons. Analyses were conducted from April to June 2010. Forty-four percent read at or below the 6th-grade level. Individual interviews revealed that <50% of participants routinely examine product label information. Only 31% know acetaminophen is in Tylenol®. The groups achieved consensus on a preferred icon for acetaminophen, desired explicit statement of potential liver damage in the warning against simultaneous use of acetaminophen products, and indicated preference for an icon and wording for maximum dose. With the high prevalence of OTC use, a consumer-centered approach to developing icons and messages to promote awareness and safe use of acetaminophen could benefit consumers. Copyright © 2011 American Journal of Preventive Medicine. Published by Elsevier Inc. All rights reserved.

The effect of dose heterogeneity on radiation risk in medical imaging.

PubMed

Samei, Ehsan; Li, Xiang; Chen, Baiyu; Reiman, Robert

2013-06-01

The current estimations of risk associated with medical imaging procedures rely on assessing the organ dose via direct measurements or simulation. The dose to each organ is assumed to be homogeneous. To take into account the differences in radiation sensitivities, the mean organ doses are weighted by a corresponding tissue-weighting coefficients provided by ICRP to calculate the effective dose, which has been used as a surrogate of radiation risk. However, those coefficients were derived under the assumption of a homogeneous dose distribution within each organ. That assumption is significantly violated in most medical-imaging procedures. In helical chest CT, for example, superficial organs (e.g. breasts) demonstrate a heterogeneous dose distribution, whereas organs on the peripheries of the irradiation field (e.g. liver) might possess a discontinuous dose profile. Projection radiography and mammography involve an even higher level of organ dose heterogeneity spanning up to two orders of magnitude. As such, mean dose or point measured dose values do not reflect the maximum energy deposited per unit volume of the organ. In this paper, the magnitude of the dose heterogeneity in both CT and projection X-ray imaging was reported, using Monte Carlo methods. The lung dose demonstrated factors of 1.7 and 2.2 difference between the mean and maximum dose for chest CT and radiography, respectively. The corresponding values for the liver were 1.9 and 3.5. For mammography and breast tomosynthesis, the difference between mean glandular dose and maximum glandular dose was 3.1. Risk models based on the mean dose were found to provide a reasonable reflection of cancer risk. However, for leukaemia, they were found to significantly under-represent the risk when the organ dose distribution is heterogeneous. A systematic study is needed to develop a risk model for heterogeneous dose distributions.

[The epidemiological validation of the MPEL for grain dust in the atmosphere].

PubMed

Pinigin, M A; Cherepov, E M; Safiulin, A A; Petrova, I V; Mukhambetova, L Kh; Osipova, E M; Veselov, A P

1998-01-01

The use of calculating and gravimetric methods for examining the grain dust pollution of the ambient air at the site of an elevator determined the maximum single, mean daily, and mean annual concentrations at different distances from the source of dust emission. The mean ratio of these concentrations was 12.1:4.3:1, respectively. The calculated concentration-effect and concentration-time relationships provided evidence for the maximum single, mean daily, and mean annual allowable concentrations for grain dust in the ambient air.

Inhalation dose assessment of indoor radon progeny using biokinetic and dosimetric modeling and its application to Jordanian population.

PubMed

Al-Jundi, J; Li, W B; Abusini, M; Tschiersch, J; Hoeschen, C; Oeh, U

2011-06-01

High indoor radon concentrations in Jordan result in internal exposures of the residents due to the inhalation of radon and its short-lived progeny. It is therefore important to quantify the annual effective dose and further the radiation risk to the radon exposure. This study describes the methodology and the biokinetic and dosimetric models used for calculation of the inhalation doses exposed to radon progeny. The regional depositions of aerosol particles in the human respiratory tract were firstly calculated. For the attached progeny, the activity median aerodynamic diameters of 50 nm, 230 nm and 2500 nm were chosen to represent the nucleation, accumulation and coarse modes of the aerosol particles, respectively. For the unattached progeny, the activity median thermodynamic diameter of 1 nm was chosen to represent the free progeny nuclide in the room air. The biokinetic models developed by the International Commission on Radiological Protection (ICRP) were used to calculate the nuclear transformations of radon progeny in the human body, and then the dosimetric model was applied to estimate the organ equivalent doses and the effective doses with the specific effective energies derived from the mathematical anthropomorphic phantoms. The dose conversion coefficient estimated in this study was 15 mSv WLM(-1) which was in the range of the values of 6-20 mSv WLM(-1) reported by other investigators. Implementing the average indoor radon concentration in Jordan, the annual effective doses were calculated to be 4.1 mSv y(-1) and 0.08 mSv y(-1) due to the inhalation of radon progeny and radon gas, respectively. The total annual effective dose estimated for Jordanian population was 4.2 mSv y(-1). This high annual effective dose calculated by the dosimetric approach using ICRP biokinetic and dosimetric models resulted in an increase of a factor of two in comparison to the value by epidemiological study. This phenomenon was presented by the ICRP in its new published statement on radon. Copyright © 2011 Elsevier Ltd. All rights reserved.

Individual external doses below the lowest reference level of 1 mSv per year five years after the 2011 Fukushima nuclear accident among all children in Soma City, Fukushima: A retrospective observational study.

PubMed

Tsubokura, Masaharu; Murakami, Michio; Nomura, Shuhei; Morita, Tomohiro; Nishikawa, Yoshitaka; Leppold, Claire; Kato, Shigeaki; Kami, Masahiro

2017-01-01

After the 2011 Fukushima Daiichi nuclear power plant accident, little information has been available on individual doses from external exposure among residents living in radioactively contaminated areas near the nuclear plant; in the present study we evaluated yearly changes in the doses from external exposure after the accident and the effects of decontamination on external exposure. This study considered all children less than 16 years of age in Soma City, Fukushima who participated in annual voluntary external exposure screening programs during the five years after the accident (n = 5,363). In total, 14,405 screening results were collected. The median participant age was eight years. The geometric mean levels of annual additional doses from external exposure attributable to the Fukushima accident, decreased each year: 0.60 mSv (range: not detectable (ND)-4.29 mSv), 0.37 mSv (range: ND-3.61 mSv), 0.22 mSv (range: ND-1.44 mSv), 0.20 mSv (range: ND-1.87 mSv), and 0.17 mSv (range: ND-0.85 mSv) in 2011, 2012, 2013, 2014, and 2015, respectively. The proportion of residents with annual additional doses from external exposure of more than 1 mSv dropped from 15.6% in 2011 to zero in 2015. Doses from external exposure decreased more rapidly than those estimated from only physical decay, even in areas without decontamination (which were halved in 395 days from November 15, 2011), presumably due to the weathering effects. While the ratios of geometric mean doses immediately after decontamination to before were slightly lower than those during the same time in areas without decontamination, annual additional doses reduced by decontamination were small (0.04-0.24 mSv in the year of immediately after decontamination was completed). The results of this study showed that the levels of external exposure among Soma residents less than 16 years of age decreased during the five years after the Fukushima Daiichi nuclear power plant accident. Decontamination had only limited and temporal effects on reducing individual external doses.

Regional peculiarities in the inter-annual distribution of the red 630.0 nm line nightglow intensities over Abastumani

NASA Astrophysics Data System (ADS)

Toriashvili, L.; Didebulidze, G. G.; Todua, M.

2017-12-01

Peculiarities of the inter-annual distribution of atomic oxygen red OI 630.0 nm line nightglow intensity observed from Abastumani Astrophysical Observatory (41.75 N; 42.82 E) are considered, using the long-term dataset. This distribution demonstrates semi-annual and annual-like variations which occur during solar minimum, as well as maximum phases. The maximum values of the red line intensities are in Summer, however in June it is lower than in May and July, which may be due to regional effects. This phenomenon is considered as a the possible result of regional dynamical processes influencing the behavior of the ionosphere F2 layer which cause changes of electrons/ions densities in the 630.0 nm line luminous region (maximum luminous layer is at about 230-280 km). Using the red line intensities and ionosphere F2 layer electron density data of the IRI-12 model, the changes of meridional thermospheric wind velocities are estimated for this mid-latitude region. These meridional and vertical wind field changes causes of variations of the red line intensities in June can be caused by tidal wind and accompanied by atmospheric gravity waves activities.

Persistent use of against-label statin-fibrate combinations from 2003-2009 despite United States Food and Drug Administration dose restrictions.

PubMed

Alford, Julie C; Saseen, Joseph J; Allen, Richard R; Nair, Kavita V

2012-07-01

To describe the prevalence of prescribing against-label statin-fibrate combination therapy. Retrospective cohort study. Medstat MarketScan Commercial Claims and Encounter database. Adults (aged 18-89 yrs) who were prescribed statin-fibrate combination therapy between January 1, 2003, and June 30, 2009, had pharmacy claims demonstrating two or more concurrently filled prescriptions for a statin and a fibrate, and had continuous insurance enrollment for at least 12 months. Claims data were used to identify patients with dyslipidemia based on International Classification of Diseases, Ninth Revision, Clinical Modification diagnosis codes. National Drug Codes were used to describe concurrent statin-fibrate combination therapy. The primary outcome was recent use of against-label statin-fibrate combination therapy, defined as use during the last 18 months (January 1, 2008-June 30, 2009) of the study period. Patients were stratified according to statin and dosage to identify against-label combination use (e.g., simvastatin > 10 mg/day with gemfibrozil). Within the recent-use period, 131,394 patients were prescribed concurrent statin-fibrate combination therapy; of these patients, 13,420 (10.2%) had against-label therapy. Simvastatin-gemfibrozil accounted for 8978 (66.9%) of all against-label combinations. Of all 9877 simvastatin-gemfibrozil combinations prescribed in the recent-use period (both on-label and against-label use), 8978 (90.9%) were against label. The secondary outcome was prevalence of against-label statin-fibrate combination therapy on an annual basis: 15.5% in 2003, 18.7% in 2004, 9.1% in 2005, 8.3% in 2006, 9.2% in 2007, and 9.8% in 2008. Against-label statin-fibrate combination therapy continues to be prescribed despite established United States Food and Drug Administration (FDA) dose restrictions. Nearly every time the simvastatin-gemfibrozil combination was prescribed, it was against label because simvastatin exceeded the maximum dose restriction. Updated simvastatin labeling in June 2011 includes additional maximum dose restrictions and new contraindications, which include gemfibrozil. Different approaches in clinical practice are needed to ensure adherence with the revised FDA labeling. © 2012 Pharmacotherapy Publications, Inc. All rights reserved.

Continuous Toxicological Dose-Response Relationships Are Pretty Homogeneous (Society for Risk Analysis Annual Meeting)

EPA Science Inventory

Dose-response relationships for a wide range of in vivo and in vitro continuous datasets are well-described by a four-parameter exponential or Hill model, based on a recent analysis of multiple historical dose-response datasets, mostly with more than five dose groups (Slob and Se...

Assessment of radiation doses from residential smoke detectors that contain americium-241

DOE Office of Scientific and Technical Information (OSTI.GOV)

O'Donnell, F.R.; Etnier, E.L.; Holton, G.A.

1981-10-01

External dose equivalents and internal dose commitments were estimated for individuals and populations from annual distribution, use, and disposal of 10 million ionization chamber smoke detectors that contain 110 kBq (3 ..mu..Ci) americium-241 each. Under exposure scenarios developed for normal distribution, use, and disposal using the best available information, annual external dose equivalents to average individuals were estimated to range from 4 fSv (0.4 prem) to 20 nSv (2 ..mu..rem) for total body and from 7 fSv to 40 nSv for bone. Internal dose commitments to individuals under post disposal scenarios were estimated to range from 0.006 to 80 ..mu..Svmore » (0.0006 to 8 mrem) to total body and from 0.06 to 800 ..mu..Sv to bone. The total collective dose (the sum of external dose equivalents and 50-year internal dose commitments) for all individuals involved with distribution, use, or disposal of 10 million smoke detectors was estimated to be about 0.38 person-Sv (38 person-rem) to total body and 00 ft/sup 2/).« less

Investigation of natural effective gamma dose rates case study: Ardebil Province in Iran

PubMed Central

2012-01-01

Gamma rays pose enough energy to induce chemical changes that may be biologically important for the normal functioning of body cells. The external exposure of human beings to natural environmental gamma radiation normally exceeds that from all man-made sources combined. In this research natural background gamma dose rates and corresponding annual effective doses were determined for selected cities of Ardebil province. Outdoor gamma dose rates were measured using an Ion Chamber Survey Meter in 105 locations in selected districts. Average absorbed doses for Ardebil, Sar-Ein, Germy, Neer, Shourabil Recreational Lake, and Kosar were determined as 265, 219, 344, 233, 352, and 358 nSv/h, respectively. Although dose rates recorded for Germi and Kosar are comparable with some areas with high natural radiation background, however, the dose rates in other districts are well below the levels reported for such locations. Average annual effective dose due to indoor and outdoor gamma radiation for Ardebil province was estimated as 1.73 (1.35–2.39) mSv, which is on average 2 times higher than the world population weighted average. PMID:23369115

34 CFR 674.12 - Loan maximums.

Code of Federal Regulations, 2011 CFR

2011-07-01

..., DEPARTMENT OF EDUCATION FEDERAL PERKINS LOAN PROGRAM General Provisions § 674.12 Loan maximums. (a) The maximum annual amount of Federal Perkins Loans and NDSLs an eligible student may borrow is— (1) $5,500 for... professional student. (b) The aggregate unpaid principal amount of all Federal Perkins Loans and NDSLs received...

Annual maximum and minimum lake levels for Indiana, 1942-85

USGS Publications Warehouse

Fowler, Kathleen K.

1988-01-01

Indiana has many natural and manmade lakes. Lake-level data are available for 217 lakes. These data were collected during water years 1942-85 by use of staff gages and, more recently, continuous recorders. The period of record at each site ranges from 1 to 43 years. Data from the lake stations have been compiled, and maximum and minimum lake levels for each year of record are reported. In addition to annual maximum and minimum lake levels, each lake station is described by gage location, surface area, drainage area, period of record, datum of gage, gage type, established legal level, lake level control, inlets and outlets, and extremes for the period of record. 

Dose and Dose Risk Caused by Natural Phenomena - Proposed Powder Metallurgy Core Manufacturing Facility

DOE Office of Scientific and Technical Information (OSTI.GOV)

Holmes, W.G.

2001-08-16

The offsite radiological effects from high velocity straight winds, tornadoes, and earthquakes have been estimated for a proposed facility for manufacturing enriched uranium fuel cores by powder metallurgy. Projected doses range up to 30 mrem/event to the maximum offsite individual for high winds and up to 85 mrem/event for very severe earthquakes. Even under conservative assumptions on meteorological conditions, the maximum offsite dose would be about 20 per cent of the DOE limit for accidents involving enriched uranium storage facilities. The total dose risk is low and is dominated by the risk from earthquakes. This report discusses this test.

Estimation and prediction of maximum daily rainfall at Sagar Island using best fit probability models

NASA Astrophysics Data System (ADS)

Mandal, S.; Choudhury, B. U.

2015-07-01

Sagar Island, setting on the continental shelf of Bay of Bengal, is one of the most vulnerable deltas to the occurrence of extreme rainfall-driven climatic hazards. Information on probability of occurrence of maximum daily rainfall will be useful in devising risk management for sustaining rainfed agrarian economy vis-a-vis food and livelihood security. Using six probability distribution models and long-term (1982-2010) daily rainfall data, we studied the probability of occurrence of annual, seasonal and monthly maximum daily rainfall (MDR) in the island. To select the best fit distribution models for annual, seasonal and monthly time series based on maximum rank with minimum value of test statistics, three statistical goodness of fit tests, viz. Kolmogorove-Smirnov test (K-S), Anderson Darling test ( A 2 ) and Chi-Square test ( X 2) were employed. The fourth probability distribution was identified from the highest overall score obtained from the three goodness of fit tests. Results revealed that normal probability distribution was best fitted for annual, post-monsoon and summer seasons MDR, while Lognormal, Weibull and Pearson 5 were best fitted for pre-monsoon, monsoon and winter seasons, respectively. The estimated annual MDR were 50, 69, 86, 106 and 114 mm for return periods of 2, 5, 10, 20 and 25 years, respectively. The probability of getting an annual MDR of >50, >100, >150, >200 and >250 mm were estimated as 99, 85, 40, 12 and 03 % level of exceedance, respectively. The monsoon, summer and winter seasons exhibited comparatively higher probabilities (78 to 85 %) for MDR of >100 mm and moderate probabilities (37 to 46 %) for >150 mm. For different recurrence intervals, the percent probability of MDR varied widely across intra- and inter-annual periods. In the island, rainfall anomaly can pose a climatic threat to the sustainability of agricultural production and thus needs adequate adaptation and mitigation measures.

Clinical assessment of the jaw-tracking function in IMRT for a brain tumor

NASA Astrophysics Data System (ADS)

Kim, Jin-Young; Kim, Shin-Wook; Choe, Bo-Young; Suh, Tae-Suk; Park, Sung-Kwang; Jo, Sun-Mi; Oh, Won-Yong; Shin, Jung-Wook; Cho, Gyu-Seok; Nam, Sang-Hee; Chung, Jin-Beom; Kim, Jung-Ki; Lee, Young-Kyu

2015-01-01

Intensity-modulated radiotherapy (IMRT) improves dose conformity and saves critical organs. IMRT is widely used in cases of head and neck, prostate, and brain cancer due to the close location of the targets to critical structures. However, because IMRT has a larger amount of radiation exposure than 3 dimensional-conformal radiation therapy (3D-CRT), it has disadvantages such as increases in the low dose irradiation to normal tissues and in the accumulated dose for the whole volume due to leakage and transmission of the multi-leaf collimator (MLC). The increased accumulated dose and the larger low dose may increase the occurrence of secondary malignant neoplasms. For these reasons, the jaw-tracking function of the TrueBeam (Varian Medical Systems, Palo Alto, CA) was developed to reduce the leakage and the transmission dose of the MLC with linear accelerators. However, the change in the superficial dose has not been verified with a quantitative analysis of the dose reduction in a brain tumor. Therefore, in the present study, we intended to verify the clinical possibility of utilizing the jaw-tracking function for a brain tumor by comparing treatment plans and superficial doses. To accomplish this, we made three types of original treatment plans using Eclipse11 (Varian Medical Systems, Palo Alto, CA): 1) farther than 2 cm from the organs at risk (OAR); 2) within 2 cm of the OAR; and 3) intersecting with the OAR. Jaw-tracking treatment plans were also made with copies of the original treatment plan using Smart LMC Version 11.0.31 (Varian Medical Systems, Palo Alto, CA). A comparison between the original treatment plans and jaw-tracking treatment plans was performed using the difference of the mean dose and maximum dose to the OARs in cumulative Dose Volume Histogram (DVH). In addition, the dependencies of the effects of transmission and the scattering doses according to jaw motion were assessed through the difference in the surface doses. In the DVH comparison, a maximum dose difference of 0.4% was observed between the planning methods in the case of over 2 cm distance, and the maximum dose of 0.6% was obtained for within the 2 cm distance. For the case intersecting with the OAR, the maximum dose difference of 2.3% was achieved. According to these results, the differences in the mean doses and the maximum doses to the OARs ware larger when the OARs and the planning target volume (PTV) were closer. In addition, small differences in the surface dose measurements were observed. In the case of the inside field, the differences were under 2% of the prescription dose while the difference was under 0.1% in the case of the outside field. Therefore, treatment plans with the jaw-tracking function consistently affected the dose reduction for a brain tumor, and the clinical possibility could be verified as the surface dose was not increased.

Evaluation of World Population-Weighted Effective Dose due to Cosmic Ray Exposure

PubMed Central

Sato, Tatsuhiko

2016-01-01

After the release of the Report of the United Nations Scientific Committee of the Effects of Atomic Radiation in 2000 (UNSCEAR2000), it became commonly accepted that the world population-weighted effective dose due to cosmic-ray exposure is 0.38 mSv, with a range from 0.3 to 2 mSv. However, these values were derived from approximate projections of altitude and geographic dependences of the cosmic-ray dose rates as well as the world population. This study hence re-evaluated the population-weighted annual effective doses and their probability densities for the entire world as well as for 230 individual nations, using a sophisticated cosmic-ray flux calculation model in tandem with detailed grid population and elevation databases. The resulting world population-weighted annual effective dose was determined to be 0.32 mSv, which is smaller than the UNSCEAR’s evaluation by 16%, with a range from 0.23 to 0.70 mSv covering 99% of the world population. These values were noted to vary with the solar modulation condition within a range of approximately 15%. All assessed population-weighted annual effective doses as well as their statistical information for each nation are provided in the supplementary files annexed to this report. These data improve our understanding of cosmic-ray radiation exposures to populations globally. PMID:27650664

Effects on vitamin A deficiency in children of periodic high-dose supplements and of fortified oil promotion in a deficient area of the Philippines.

PubMed

Mason, John B; Ramirez, Maria A; Fernandez, Chona M; Pedro, Regina; Lloren, Tina; Saldanha, Lisa; Deitchler, Megan; Eisele, T

2011-09-01

Regular semi-annual distribution of high-dose (200,000 IU) vitamin A capsules (VACs) to children 1 - 5 years of age (previously identified as underweight), in Leyte Province, the Philippines, was compared to providing extra VACs to give three-monthly dosing, and to vitamin A-fortified cooking oil (VAFO) promotion (with continued VACs every 6 months). Serum retinol (SR) was measured at baseline and after 12 or 18 months (for VAFO). No sustained increase in SR was determined from the three-month VAC dosing regimen, and the prevalence of vitamin A deficiency (VAD) as assessed by SR (< 20 mcg / dL) remained around 30 % (in line with national survey estimates over the previous 15 years). The major difference found was that 18 months of VAFO (of which 9 months had sustained promotion) was associated with reducing the prevalence of VAD to < 10 %. The effective fortification and lack of effect of semi-annual VAC results are in line with previous studies; testing with dosing of VAC every three months is a new intervention. The results imply that promotion of fortified oil would reduce VAD in these conditions; whether it can replace or needs to be added to semi-annual VAC dosing remains to be determined. A phased changeover to reliance on fortified commodities (including oil) with careful monitoring of VAD trends is indicated.

Eye lens dosimetry and the study on radiation cataract in interventional cardiologists.

PubMed

Matsubara, Kosuke; Lertsuwunseri, Vorarit; Srimahachota, Suphot; Krisanachinda, Anchali; Tulvatana, Wasee; Khambhiphant, Bharkbhum; Sudchai, Waraporn; Rehani, Madan

2017-12-01

To determine the eye lens dose of the Interventional Cardiology (IC) personnel using optically stimulated luminescent dosimeter (OSLD) and the prevalence and risk of radiation - associated lens opacities in Thailand. 48 IC staff, with age- and sex- matches 37 unexposed controls obtained eye examines. Posterior lens change was graded using a modified Merriam-Focht technique by two independent ophthalmologists. Occupational exposure (mSv) was measured in 42 IC staff, using 2 OSLD badges place at inside lead apron and at collar. Annual eye lens doses (mSv) were also measured using 4 nanoDots OSL placed outside and inside lead glass eyewear. The prevalence of radiation-associated posterior lens opacities was 28.6% (2/7) for IC, 19.5% (8/41) for nurses, and 2.7% (1/37) for controls. The average and range of annual whole body effective dose, Hp(10), equivalent dose at skin of the neck, Hp(0.07) and equivalent dose at eye lens, Hp(3) were 0.80 (0.05-6.79), 5.88 (0.14-35.28), and 5.73 (0.14-33.20) mSv respectively. The annual average and range of eye lens dose using nano Dots OSL showed the outside lead glass eyewear on left and right sides as 8.06 (0.17-32.45), 3.55(0.06-8.04) mSv and inside left and right sides as 3.91(0.05-14.26) and 2.44(0.06-6.24) mSv respectively. Eye lens doses measured by OSLD badges and nano Dot dosimeter as Hp(10), Hp(0.07) and Hp(3). The eyes of the IC personnel were examined annually by two ophthalmologists for the prevalence of cataract induced by radiation. Copyright © 2017 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.

78 FR 18249 - Fisheries Off West Coast States; Coastal Pelagic Species Fisheries; Annual Specifications

Federal Register 2010, 2011, 2012, 2013, 2014

2013-03-26

... limit (ACL), harvest guideline (HG), annual catch target (ACT) and associated annual reference points... Coastal Pelagic Species (CPS) Fishery Management Plan (FMP). The 2012-2013 ACL or maximum HG for Pacific... difference between the ACL and ACT (10,128 mt) as a set aside for incidental landings in other CPS fisheries...

77 FR 36192 - Fisheries Off West Coast States; Coastal Pelagic Species Fisheries; Annual Specifications

Federal Register 2010, 2011, 2012, 2013, 2014

2012-06-18

... limit (ACL), harvest guideline (HG), annual catch target (ACT) and associated annual reference points... year season of July 1, 2011, through June 30, 2012. NMFS establishes the ACL, HG, and ACT under the... off the Pacific coast. The ACL (or maximum HG) for the 2011- 2012 Pacific mackerel fishing year is 40...

An analysis of annual maximum streamflows in Terengganu, Malaysia using TL-moments approach

NASA Astrophysics Data System (ADS)

Ahmad, Ummi Nadiah; Shabri, Ani; Zakaria, Zahrahtul Amani

2013-02-01

TL-moments approach has been used in an analysis to determine the best-fitting distributions to represent the annual series of maximum streamflow data over 12 stations in Terengganu, Malaysia. The TL-moments with different trimming values are used to estimate the parameter of the selected distributions namely: generalized pareto (GPA), generalized logistic, and generalized extreme value distribution. The influence of TL-moments on estimated probability distribution functions are examined by evaluating the relative root mean square error and relative bias of quantile estimates through Monte Carlo simulations. The boxplot is used to show the location of the median and the dispersion of the data, which helps in reaching the decisive conclusions. For most of the cases, the results show that TL-moments with one smallest value was trimmed from the conceptual sample (TL-moments (1,0)), of GPA distribution was the most appropriate in majority of the stations for describing the annual maximum streamflow series in Terengganu, Malaysia.

Natural radionuclides in cigarette tobacco from Serbian market and effective dose estimate from smoke inhalation.

PubMed

Janković Mandić, Ljiljana; Đolić, Maja; Marković, Dragana; Todorović, Dragana; Onjia, Antonije; Dragović, Snežana

2016-01-01

The activity concentrations of natural radionuclides ((40)K, (210)Pb, (210)Po, (226)Ra and (228)Ra) in 17 most frequently used cigarette brands in Serbia and corresponding effective doses due to smoke inhalation are presented. The mean annual effective doses for (210)Pb and (210)Po were estimated to be 47.3 and 724 µSv y(-1) for (210)Pb and (210)Po, respectively. Serbia currently has the highest smoking rate in the world. The results of this study indicate the high contribution of the annual effective dose due to smoke inhalation to the total inhalation dose from natural radionuclides. The more effective implementation of actions for reducing smoking prevalence in Serbia is highly needed. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Ultraviolet radiation in the Atacama Desert.

PubMed

Cordero, R R; Damiani, A; Jorquera, J; Sepúlveda, E; Caballero, M; Fernandez, S; Feron, S; Llanillo, P J; Carrasco, J; Laroze, D; Labbe, F

2018-03-31

The world's highest levels of surface ultraviolet (UV) irradiance have been measured in the Atacama Desert. This area is characterized by its high altitude, prevalent cloudless conditions, and a relatively low total ozone column. In this paper, we provide estimates of the surface UV (monthly UV index at noon and annual doses of UV-B and UV-A) for all sky conditions in the Atacama Desert. We found that the UV index at noon during the austral summer is expected to be greater than 11 in the whole desert. The annual UV-B (UV-A) doses were found to range from about 3.5 kWh/m 2 (130 kWh/m 2 ) in coastal areas to 5 kWh/m 2 (160 kWh/m 2 ) on the Andean plateau. Our results confirm significant interhemispherical differences. Typical annual UV-B doses in the Atacama Desert are about 40% greater than typical annual UV-B doses in northern Africa. Mostly due to seasonal changes in the ozone, the differences between the Atacama Desert and northern Africa are expected to be about 60% in the case of peak UV-B levels (i.e. the UV-B irradiances at noon close to the summer solstice in each hemisphere). Interhemispherical differences in the UV-A are significantly lower since the effect of the ozone in this part of the spectrum is minor.

Developability assessment of clinical drug products with maximum absorbable doses.

PubMed

Ding, Xuan; Rose, John P; Van Gelder, Jan

2012-05-10

Maximum absorbable dose refers to the maximum amount of an orally administered drug that can be absorbed in the gastrointestinal tract. Maximum absorbable dose, or D(abs), has proved to be an important parameter for quantifying the absorption potential of drug candidates. The purpose of this work is to validate the use of D(abs) in a developability assessment context, and to establish appropriate protocol and interpretation criteria for this application. Three methods for calculating D(abs) were compared by assessing how well the methods predicted the absorption limit for a set of real clinical candidates. D(abs) was calculated for these clinical candidates by means of a simple equation and two computer simulation programs, GastroPlus and an program developed at Eli Lilly and Company. Results from single dose escalation studies in Phase I clinical trials were analyzed to identify the maximum absorbable doses for these compounds. Compared to the clinical results, the equation and both simulation programs provide conservative estimates of D(abs), but in general D(abs) from the computer simulations are more accurate, which may find obvious advantage for the simulations in developability assessment. Computer simulations also revealed the complex behavior associated with absorption saturation and suggested in most cases that the D(abs) limit is not likely to be achieved in a typical clinical dose range. On the basis of the validation findings, an approach is proposed for assessing absorption potential, and best practices are discussed for the use of D(abs) estimates to inform clinical formulation development strategies. Copyright © 2012 Elsevier B.V. All rights reserved.

Assessment of natural radioactivity and associated radiological risks from tiles used in Kajang, Malaysia

NASA Astrophysics Data System (ADS)

Abdullahi, S.; Ismail, A. F.; Samat, S. B.; Yasir, M. S.

2018-04-01

The activity concentration and radiological risk of commonly used flooring materials (tiles) in Malaysia were studied. The natural radionuclide concentrations of 226Ra, 232Th and 40K were measured using high-purity germanium detector. The average concentration of 226Ra, 232Th and 40K in the samples were 65.75±1.1 Bq kg-1, 61.92±1.43 Bq kg-1 and 617.77±6.72 Bq kg-1 respectively. The mean concentration of radium equivalent activity, absorbed dose rate, external and internal hazard indices and annual effective dose equivalent were 195.21±2.88 Bq kg-1, 92.75±1.27 nGy h-1, 0.53±0.01, 0.7±0.01 and 0.44±0.0 mSv y-1 respectively. The aim was to assess the possible radiological risks attributed from the tile materials. Even though, the activity concentrations were higher than worldwide average values, but none of the radiological impact parameters exceeded the maximum recommended values. Hence, it was concluded that, contribution of tiles to radiation exposure is negligible and therefore, radiologically safe to use as building materials.

Individual dose adjustment of riociguat in patients with pulmonary arterial hypertension and chronic thromboembolic pulmonary hypertension.

PubMed

Hill, Nicholas S; Rahaghi, Franck F; Sood, Namita; Frey, Reiner; Ghofrani, Hossein-Ardeschir

2017-08-01

Riociguat is a soluble guanylate cyclase stimulator that has been approved for the treatment of pulmonary arterial hypertension and inoperable chronic thromboembolic pulmonary hypertension or persistent/recurrent pulmonary hypertension following pulmonary endarterectomy. Riociguat is administered using an 8-week individual dose-adjustment scheme whereby a patient initially receives riociguat 1.0 mg three times daily (tid), and the dose is then increased every 2 weeks in the absence of hypotension, indicated by systolic blood pressure measurements and symptoms, up to a maximum dose of 2.5 mg tid. The established riociguat dose-adjustment scheme allows the dose of riociguat to be individually optimized in terms of tolerability and efficacy. The majority of patients in the phase III clinical trials and their long-term extension phases achieved the maximum riociguat dose, whereas some patients remained on lower doses. There is evidence that these patients may experience benefits at riociguat doses lower than 2.5 mg tid, with improvement in exercise capacity being observed after only 2-4 weeks of treatment in the phase III studies and in the exploratory 1.5 mg-maximum patient group of PATENT-1. This review aims to provide an overview of the rationale behind the riociguat dose-adjustment scheme and examine its application to both clinical trials and real-life clinical practice. Copyright © 2017 Elsevier Ltd. All rights reserved.

Multileaf collimator tongue-and-groove effect on depth and off-axis doses: A comparison of treatment planning data with measurements and Monte Carlo calculations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kim, Hee Jung; Department of Biomedical Engineering, Seoul National University, Seoul; Department of Radiation Oncology, Soonchunhyang University Hospital, Seoul

2015-01-01

To investigate how accurately treatment planning systems (TPSs) account for the tongue-and-groove (TG) effect, Monte Carlo (MC) simulations and radiochromic film (RCF) measurements were performed for comparison with TPS results. Two commercial TPSs computed the TG effect for Varian Millennium 120 multileaf collimator (MLC). The TG effect on off-axis dose profile at 3 depths of solid water was estimated as the maximum depth and the full width at half maximum (FWHM) of the dose dip at an interleaf position. When compared with the off-axis dose of open field, the maximum depth of the dose dip for MC and RCF rangedmore » from 10.1% to 20.6%; the maximum depth of the dose dip gradually decreased by up to 8.7% with increasing depths of 1.5 to 10 cm and also by up to 4.1% with increasing off-axis distances of 0 to 13 cm. However, TPS results showed at most a 2.7% decrease for the same depth range and a negligible variation for the same off-axis distances. The FWHM of the dose dip was approximately 0.19 cm for MC and 0.17 cm for RCF, but 0.30 cm for Eclipse TPS and 0.45 cm for Pinnacle TPS. Accordingly, the integrated value of TG dose dip for TPS was larger than that for MC and RCF and almost invariant along the depths and off-axis distances. We concluded that the TG dependence on depth and off-axis doses shown in the MC and RCF results could not be appropriately modeled by the TPS versions in this study.« less

Luminescence (IRSL) dating of Yeni Rabat church in Artvin, Turkey

NASA Astrophysics Data System (ADS)

Şahiner, Eren; Meriç, Niyazi; Uygun, Selda

2013-05-01

Luminescence dating is a chronological method that has been used extensively in terrestrial materials. In this study, we present Infrared Stimulated Luminescence (IRSL) dating results obtained for sediment and pottery samples taken from Yeni Rabat Church, Ardanuç, Artvin, Turkey. For this purpose, equivalent dose (ED) and annual dose rate (AD) of samples were measured. For annual dose rate, concentrations of radioactive isotopes (U, Th, K) were determined by using a high-purity germanium detector. For the equivalent dose, polymineral fine grain SAR (Single Aliquot Regenerative Dose) and MAAD (Multiple Aliquot Additive Dose) procedures were used. The optimal preheat temperature was determined for sediment and pottery samples. Ages were calculated by Aitken's luminescence age calculation method, which found 710±190 years for the pottery sample and 1450±370 years, 1390±420 years, 1430±310 years, 2210±520 years and 1640±390 years for different sediment samples, respectively. These estimated age ranges support the theory that Yeni Rabat Church could have been constructed in medieval times.

Constraining continuous rainfall simulations for derived design flood estimation

NASA Astrophysics Data System (ADS)

Woldemeskel, F. M.; Sharma, A.; Mehrotra, R.; Westra, S.

2016-11-01

Stochastic rainfall generation is important for a range of hydrologic and water resources applications. Stochastic rainfall can be generated using a number of models; however, preserving relevant attributes of the observed rainfall-including rainfall occurrence, variability and the magnitude of extremes-continues to be difficult. This paper develops an approach to constrain stochastically generated rainfall with an aim of preserving the intensity-durationfrequency (IFD) relationships of the observed data. Two main steps are involved. First, the generated annual maximum rainfall is corrected recursively by matching the generated intensity-frequency relationships to the target (observed) relationships. Second, the remaining (non-annual maximum) rainfall is rescaled such that the mass balance of the generated rain before and after scaling is maintained. The recursive correction is performed at selected storm durations to minimise the dependence between annual maximum values of higher and lower durations for the same year. This ensures that the resulting sequences remain true to the observed rainfall as well as represent the design extremes that may have been developed separately and are needed for compliance reasons. The method is tested on simulated 6 min rainfall series across five Australian stations with different climatic characteristics. The results suggest that the annual maximum and the IFD relationships are well reproduced after constraining the simulated rainfall. While our presentation focusses on the representation of design rainfall attributes (IFDs), the proposed approach can also be easily extended to constrain other attributes of the generated rainfall, providing an effective platform for post-processing of stochastic rainfall generators.

Measurement of natural radioactivity and assessment of associated radiation hazards in soil around Baoji second coal-fired thermal power plant, China.

PubMed

Lu, Xinwei; Li, Xiaoxue; Yun, Pujun; Luo, Dacheng; Wang, Lijun; Ren, Chunhui; Chen, Cancan

2012-01-01

Activity concentrations of natural radionuclides (226)Ra, (232)Th and (40)K in soil around Baoji Second coal-fired thermal power plant of China were determined using gamma ray spectrometry. The mean activity concentrations of (226)Ra, (232)Th and (40)K in soil were found to be 40.3 ± 3.5, 59.6 ± 3.1 and 751.2 ± 12.4 Bq kg(-1), respectively, which are all higher than the corresponding average values in Shaanxi, Chinese and world soil. The radium equivalent activity (Ra(eq)), the air absorbed dose rate (D), the annual effective dose (E), the external hazard index (H(ex)) and internal hazard index (H(in)) were evaluated and compared with the internationally reported or reference values. All the soil samples have Ra(eq) lower than the limit of 370 Bq kg(-1) and H(ex) and H(in) less than unity. The overall mean outdoor terrestrial gamma air absorbed dose rate is ∼86.6 ± 3.4 nGy h(-1) and the corresponding outdoor annual effective dose is 0.106 ± 0.004 mSv, which is higher than the worldwide average (0.07 mSv y(-1)) for outdoor's annual effective dose.

Biogeographical drivers of ragweed pollen concentrations in Europe

NASA Astrophysics Data System (ADS)

Matyasovszky, István; Makra, László; Tusnády, Gábor; Csépe, Zoltán; Nyúl, László G.; Chapman, Daniel S.; Sümeghy, Zoltán; Szűcs, Gábor; Páldy, Anna; Magyar, Donát; Mányoki, Gergely; Erostyák, János; Bodnár, Károly; Bergmann, Karl-Christian; Deák, Áron József; Thibaudon, Michel; Albertini, Roberto; Bonini, Maira; Šikoparija, Branko; Radišić, Predrag; Gehrig, Regula; Rybníček, Ondřej; Severova, Elena; Rodinkova, Victoria; Prikhodko, Alexander; Maleeva, Anna; Stjepanović, Barbara; Ianovici, Nicoleta; Berger, Uwe; Seliger, Andreja Kofol; Weryszko-Chmielewska, Elżbieta; Šaulienė, Ingrida; Shalaboda, Valentina; Yankova, Raina; Peternel, Renata; Ščevková, Jana; Bullock, James M.

2017-06-01

The drivers of spatial variation in ragweed pollen concentrations, contributing to severe allergic rhinitis and asthma, are poorly quantified. We analysed the spatiotemporal variability in 16-year (1995-2010) annual total (66 stations) and annual total (2010) (162 stations) ragweed pollen counts and 8 independent variables (start, end and duration of the ragweed pollen season, maximum daily and calendar day of the maximum daily ragweed pollen counts, last frost day in spring, first frost day in fall and duration of the frost-free period) for Europe (16 years, 1995-2010) as a function of geographical coordinates. Then annual total pollen counts, annual daily peak pollen counts and date of this peak were regressed against frost-related variables, daily mean temperatures and daily precipitation amounts. To achieve this, we assembled the largest ragweed pollen data set to date for Europe. The dependence of the annual total ragweed pollen counts and the eight independent variables against geographical coordinates clearly distinguishes the three highly infected areas: the Pannonian Plain, Western Lombardy and the Rhône-Alpes region. All the eight variables are sensitive to longitude through its temperature dependence. They are also sensitive to altitude, due to the progressively colder climate with increasing altitude. Both annual total pollen counts and the maximum daily pollen counts depend on the start and the duration of the ragweed pollen season. However, no significant changes were detected in either the eight independent variables as a function of increasing latitude. This is probably due to a mixed climate induced by strong geomorphological inhomogeneities in Europe.

Trends and annual cycles in soundings of Arctic tropospheric ozone

NASA Astrophysics Data System (ADS)

Christiansen, Bo; Jepsen, Nis; Kivi, Rigel; Hansen, Georg; Larsen, Niels; Smith Korsholm, Ulrik

2017-08-01

Ozone soundings from nine Nordic stations have been homogenized and interpolated to standard pressure levels. The different stations have very different data coverage; the longest period with data is from the end of the 1980s to 2014. At each pressure level the homogenized ozone time series have been analysed with a model that includes both low-frequency variability in the form of a polynomial, an annual cycle with harmonics, the possibility for low-frequency variability in the annual amplitude and phasing, and either white noise or noise given by a first-order autoregressive process. The fitting of the parameters is performed with a Bayesian approach not only giving the mean values but also confidence intervals. The results show that all stations agree on a well-defined annual cycle in the free troposphere with a relatively confined maximum in the early summer. Regarding the low-frequency variability, it is found that Scoresbysund, Ny Ålesund, Sodankylä, Eureka, and Ørland show similar, significant signals with a maximum near 2005 followed by a decrease. This change is characteristic for all pressure levels in the free troposphere. A significant change in the annual cycle was found for Ny Ålesund, Scoresbysund, and Sodankylä. The changes at these stations are in agreement with the interpretation that the early summer maximum is appearing earlier in the year. The results are shown to be robust to the different settings of the model parameters such as the order of the polynomial, number of harmonics in the annual cycle, and the type of noise.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Li, Heng, E-mail: hengli@mdanderson.org; Zhu, X. Ronald; Zhang, Xiaodong

Purpose: To develop and validate a novel delivery strategy for reducing the respiratory motion–induced dose uncertainty of spot-scanning proton therapy. Methods and Materials: The spot delivery sequence was optimized to reduce dose uncertainty. The effectiveness of the delivery sequence optimization was evaluated using measurements and patient simulation. One hundred ninety-one 2-dimensional measurements using different delivery sequences of a single-layer uniform pattern were obtained with a detector array on a 1-dimensional moving platform. Intensity modulated proton therapy plans were generated for 10 lung cancer patients, and dose uncertainties for different delivery sequences were evaluated by simulation. Results: Without delivery sequence optimization,more » the maximum absolute dose error can be up to 97.2% in a single measurement, whereas the optimized delivery sequence results in a maximum absolute dose error of ≤11.8%. In patient simulation, the optimized delivery sequence reduces the mean of fractional maximum absolute dose error compared with the regular delivery sequence by 3.3% to 10.6% (32.5-68.0% relative reduction) for different patients. Conclusions: Optimizing the delivery sequence can reduce dose uncertainty due to respiratory motion in spot-scanning proton therapy, assuming the 4-dimensional CT is a true representation of the patients' breathing patterns.« less

A comparison of skin and chest wall dose delivered with multicatheter, Contura multilumen balloon, and MammoSite breast brachytherapy.

PubMed

Cuttino, Laurie W; Todor, Dorin; Rosu, Mihaela; Arthur, Douglas W

2011-01-01

Skin and chest wall doses have been correlated with toxicity in patients treated with breast brachytherapy . This investigation compared the ability to control skin and chest wall doses between patients treated with multicatheter (MC), Contura multilumen balloon (CMLB), and MammoSite (MS) brachytherapy. 43 patients treated with the MC technique, 45 patients treated with the CMLB, and 83 patients treated with the MS were reviewed. The maximum doses delivered to the skin and chest wall were calculated for all patients. The mean maximum skin doses for the MC, CMLB, and MS were 2.3 Gy (67% of prescription dose), 2.8 Gy (82% of prescription dose), and 3.2 Gy per fraction (94% of prescription dose), respectively. Although the skin distances were similar (p = 0.23) for the two balloon techniques, the mean skin dose with the CMLB was significantly lower than with the MS (p = 0.05). The mean maximum rib doses for the MC, CMLB, and MS were 2.3 Gy (67% of prescription dose), 2.8 Gy (82% of prescription dose), and 3.6 Gy per fraction (105% of prescription dose), respectively. Again, the mean rib dose with the CMLB was significantly lower than with the MS (p = 0.002). The MC and CMLB techniques are associated with significantly lower mean skin and rib doses than is the MS. Treatment with the MS was associated with significantly more patients receiving doses to the skin or rib in excess of 125% of the prescription. Treatment with the CMLB may prove to yield less normal tissue toxicity than treatment with the MS. Copyright © 2011 Elsevier Inc. All rights reserved.

A Comparison of Skin and Chest Wall Dose Delivered With Multicatheter, Contura Multilumen Balloon, and MammoSite Breast Brachytherapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cuttino, Laurie W., E-mail: lcuttino@mcvh-vcu.ed; Todor, Dorin; Rosu, Mihaela

2011-01-01

Purpose: Skin and chest wall doses have been correlated with toxicity in patients treated with breast brachytherapy . This investigation compared the ability to control skin and chest wall doses between patients treated with multicatheter (MC), Contura multilumen balloon (CMLB), and MammoSite (MS) brachytherapy. Methods and Materials: 43 patients treated with the MC technique, 45 patients treated with the CMLB, and 83 patients treated with the MS were reviewed. The maximum doses delivered to the skin and chest wall were calculated for all patients. Results: The mean maximum skin doses for the MC, CMLB, and MS were 2.3 Gy (67%more » of prescription dose), 2.8 Gy (82% of prescription dose), and 3.2 Gy per fraction (94% of prescription dose), respectively. Although the skin distances were similar (p = 0.23) for the two balloon techniques, the mean skin dose with the CMLB was significantly lower than with the MS (p = 0.05). The mean maximum rib doses for the MC, CMLB, and MS were 2.3 Gy (67% of prescription dose), 2.8 Gy (82% of prescription dose), and 3.6 Gy per fraction (105% of prescription dose), respectively. Again, the mean rib dose with the CMLB was significantly lower than with the MS (p = 0.002). Conclusion: The MC and CMLB techniques are associated with significantly lower mean skin and rib doses than is the MS. Treatment with the MS was associated with significantly more patients receiving doses to the skin or rib in excess of 125% of the prescription. Treatment with the CMLB may prove to yield less normal tissue toxicity than treatment with the MS.« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fritz, Brad G.; Dirkes, Roger L.; Napier, Bruce A.

The Hanford Reach National Monument (HRNM) was created by presidential proclamation in 2000. It is located along the Columbia River in south central Washington and consists of five distinct units. The McGee Ranch-Riverlands and the North Slope units are addressed in this report. North Slope refers to two of the HRNM units: the Saddle Mountain Unit and the Wahluke Slope Unit. The Saddle Mountain and Wahluke Slope Units are located north of the Columbia River, while the McGee Ranch-Riverlands Unit is located south of the Columbia River and north and west of Washington State Highway 24. To fulfill internal U.S.more » Department of Energy (DOE) requirements prior to any radiological clearance of land, the DOE must evaluate the potential for residual radioactive contamination on this land and determine compliance with the requirements of DOE Order 5400.5. Authorized limits for residual radioactive contamination were developed based on the DOE annual exposure limit to the public (100 mrem) using future potential land-use scenarios. The DOE Office of Environmental Management approved these authorized limits on March 1, 2004. Historical soil monitoring conducted on and around the HRNM indicated soil concentrations of radionuclides were well below the authorized limits (Fritz et al. 2003). However, the historical sampling was done at a limited number of sampling locations. Therefore, additional soil sampling was conducted to determine if the concentrations of radionuclides in soil on the McGee Ranch-Riverlands and North Slope units were below the authorized limits. Sixty-seven soil samples were collected from the McGee Ranch-Riverlands and North Slope units. A software package (Visual Sample Plan) was used to plan the collection to assure an adequate number of samples were collected. The number of samples necessary to decide with a high level of confidence (99%) that the soil concentrations of radionuclides on the North Slope and McGee Ranch-Riverlands units did not exceed the authorized limits was determined to be 27. Additional soil samples were collected from areas suspected to have a potential for accumulation of radionuclides. This included samples collected from the riparian zone along the Columbia River, Savage Island, and other locations across the North Slope and McGee Ranch-Riverlands units. The 67 soil samples collected from the McGee Ranch-Riverlands and North Slope units all had concentrations of radionuclides far below the authorized limits established by the DOE. Statistical analysis of the results concluded that the Authorized Limits were not exceeded when total uncertainty was considered. The calculated upper confidence limit for each radionuclide measured in this study (which represents the value at which 99% of the measurements reside below with a 99% confidence level) was lower than the Authorized Limit for each radionuclide. The maximum observed soil concentrations for the radionuclides included in the authorized limits would result in a potential annual dose of 0.23 mrem assuming the most probable use scenario, a recreational visitor. This potential dose is well below the DOE 100-mrem/year dose limit for members of the public. Furthermore, the results of the biota dose assessment screen, which used the RESRAD biota code, indicated that the sum of fractions is less than one. This assumed soil concentrations equal to the maximum concentrations of radionuclides measured on the McGee Ranch-Riverlands and North Slope units’ in this study. Since the sum of fractions was less than 1, dose to terrestrial biota will not exceed the recommended biota dose limit for the soil concentrations measured in this study.« less

Quantifying the impact of immediate reconstruction in postmastectomy radiation: a large, dose-volume histogram-based analysis.

PubMed

Ohri, Nisha; Cordeiro, Peter G; Keam, Jennifer; Ballangrud, Ase; Shi, Weiji; Zhang, Zhigang; Nerbun, Claire T; Woch, Katherine M; Stein, Nicholas F; Zhou, Ying; McCormick, Beryl; Powell, Simon N; Ho, Alice Y

2012-10-01

To assess the impact of immediate breast reconstruction on postmastectomy radiation (PMRT) using dose-volume histogram (DVH) data. Two hundred forty-seven women underwent PMRT at our center, 196 with implant reconstruction and 51 without reconstruction. Patients with reconstruction were treated with tangential photons, and patients without reconstruction were treated with en-face electron fields and customized bolus. Twenty percent of patients received internal mammary node (IMN) treatment. The DVH data were compared between groups. Ipsilateral lung parameters included V20 (% volume receiving 20 Gy), V40 (% volume receiving 40 Gy), mean dose, and maximum dose. Heart parameters included V25 (% volume receiving 25 Gy), mean dose, and maximum dose. IMN coverage was assessed when applicable. Chest wall coverage was assessed in patients with reconstruction. Propensity-matched analysis adjusted for potential confounders of laterality and IMN treatment. Reconstruction was associated with lower lung V20, mean dose, and maximum dose compared with no reconstruction (all P<.0001). These associations persisted on propensity-matched analysis (all P<.0001). Heart doses were similar between groups (P=NS). Ninety percent of patients with reconstruction had excellent chest wall coverage (D95 >98%). IMN coverage was superior in patients with reconstruction (D95 >92.0 vs 75.7%, P<.001). IMN treatment significantly increased lung and heart parameters in patients with reconstruction (all P<.05) but minimally affected those without reconstruction (all P>.05). Among IMN-treated patients, only lower lung V20 in those without reconstruction persisted (P=.022), and mean and maximum heart doses were higher than in patients without reconstruction (P=.006, P=.015, respectively). Implant reconstruction does not compromise the technical quality of PMRT when the IMNs are untreated. Treatment technique, not reconstruction, is the primary determinant of target coverage and normal tissue doses. Published by Elsevier Inc.

Cosmic Radiation Exposure of Biological Test Systems During the EXPOSE-E Mission

PubMed Central

Hajek, Michael; Bilski, Pawel; Körner, Christine; Vanhavere, Filip; Reitz, Günther

2012-01-01

Abstract In the frame of the EXPOSE-E mission on the Columbus external payload facility EuTEF on board the International Space Station, passive thermoluminescence dosimeters were applied to measure the radiation exposure of biological samples. The detectors were located either as stacks next to biological specimens to determine the depth dose distribution or beneath the sample carriers to determine the dose levels for maximum shielding. The maximum mission dose measured in the upper layer of the depth dose part of the experiment amounted to 238±10 mGy, which relates to an average dose rate of 408±16 μGy/d. In these stacks of about 8 mm height, the dose decreased by 5–12% with depth. The maximum dose measured beneath the sample carriers was 215±16 mGy, which amounts to an average dose rate of 368±27 μGy/d. These values are close to those assessed for the interior of the Columbus module and demonstrate the high shielding of the biological experiments within the EXPOSE-E facility. Besides the shielding by the EXPOSE-E hardware itself, additional shielding was experienced by the external structures adjacent to EXPOSE-E, such as EuTEF and Columbus. This led to a dose gradient over the entire exposure area, from 215±16 mGy for the lowest to 121±6 mGy for maximum shielding. Hence, the doses perceived by the biological samples inside EXPOSE-E varied by 70% (from lowest to highest dose). As a consequence of the high shielding, the biological samples were predominantly exposed to galactic cosmic heavy ions, while electrons and a significant fraction of protons of the radiation belts and solar wind did not reach the samples. Key Words: Space radiation—Dosimetry—Passive radiation detectors—Thermoluminescence—EXPOSE-E. Astrobiology 12, 387–392. PMID:22680685

IDEAL-CRT: A Phase 1/2 Trial of Isotoxic Dose-Escalated Radiation Therapy and Concurrent Chemotherapy in Patients With Stage II/III Non-Small Cell Lung Cancer

DOE Office of Scientific and Technical Information (OSTI.GOV)

Landau, David B., E-mail: david.landau@kcl.ac.uk; Hughes, Laura; Baker, Angela

2016-08-01

Purpose: To report toxicity and early survival data for IDEAL-CRT, a trial of dose-escalated concurrent chemoradiotherapy (CRT) for non-small cell lung cancer. Patients and Methods: Patients received tumor doses of 63 to 73 Gy in 30 once-daily fractions over 6 weeks with 2 concurrent cycles of cisplatin and vinorelbine. They were assigned to 1 of 2 groups according to esophageal dose. In group 1, tumor doses were determined by an experimental constraint on maximum esophageal dose, which was escalated following a 6 + 6 design from 65 Gy through 68 Gy to 71 Gy, allowing an esophageal maximum tolerated dose to be determined from early and late toxicities. Tumormore » doses for group 2 patients were determined by other tissue constraints, often lung. Overall survival, progression-free survival, tumor response, and toxicity were evaluated for both groups combined. Results: Eight centers recruited 84 patients: 13, 12, and 10, respectively, in the 65-Gy, 68-Gy, and 71-Gy cohorts of group 1; and 49 in group 2. The mean prescribed tumor dose was 67.7 Gy. Five grade 3 esophagitis and 3 grade 3 pneumonitis events were observed across both groups. After 1 fatal esophageal perforation in the 71-Gy cohort, 68 Gy was declared the esophageal maximum tolerated dose. With a median follow-up of 35 months, median overall survival was 36.9 months, and overall survival and progression-free survival were 87.8% and 72.0%, respectively, at 1 year and 68.0% and 48.5% at 2 years. Conclusions: IDEAL-CRT achieved significant treatment intensification with acceptable toxicity and promising survival. The isotoxic design allowed the esophageal maximum tolerated dose to be identified from relatively few patients.« less

5 CFR 9701.312 - Maximum rates.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 5 Administrative Personnel 3 2013-01-01 2013-01-01 false Maximum rates. 9701.312 Section 9701.312... MANAGEMENT SYSTEM Pay and Pay Administration Overview of Pay System § 9701.312 Maximum rates. (a) DHS may not pay any employee an annual rate of basic pay in excess of the rate for level III of the Executive...

5 CFR 9701.312 - Maximum rates.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 5 Administrative Personnel 3 2012-01-01 2012-01-01 false Maximum rates. 9701.312 Section 9701.312... MANAGEMENT SYSTEM Pay and Pay Administration Overview of Pay System § 9701.312 Maximum rates. (a) DHS may not pay any employee an annual rate of basic pay in excess of the rate for level III of the Executive...

5 CFR 9701.312 - Maximum rates.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 5 Administrative Personnel 3 2011-01-01 2011-01-01 false Maximum rates. 9701.312 Section 9701.312... MANAGEMENT SYSTEM Pay and Pay Administration Overview of Pay System § 9701.312 Maximum rates. (a) DHS may not pay any employee an annual rate of basic pay in excess of the rate for level III of the Executive...

Variability of maximum systolic amplitude of ΔZ/Δt curve in pregnancy. Perennial observations

NASA Astrophysics Data System (ADS)

Ilyin, I.; Karpov, A.; Korotkova, M.

2010-04-01

Maximum systolic amplitude is quite an important component of the impedance cardiogram ΔZ/Δt curve. Its values make it possible to calculate many hemodynamic indices. Therefore it is necessary to keep informed about monthly, annual and perennial maximum systolic amplitude trend. We can produce the measuring data of the maximum systolic amplitude for a fifteen-year period (from 1994 to 2009). The impedance cardiograms were obtained with the help of an electric impedance analyzer "RA-5" (1 mA, 70 kHz) with disk ECG electrodes. The data analyzed were taken from the pregnant women with non-complicated pregnancy (n=5709). We have analyzed the average monthly and annual changes of the maximum systolic amplitude ΔZ/Δt curve. It allowed us to reveal the six-year periodicity of the maximum systolic amplitude changes. There were discovered statistically significant peak values difference of the amplitude (p>0.001). The data obtained should be taken into consideration when using impedance cardiography in clinical practice. The article is supplied with tables and diagrams.

Evaluation of the dependence of the exposure dose on the attenuation correction in brain PET/CT scans using 18F-FDG

NASA Astrophysics Data System (ADS)

Choi, Eun-Jin; Jeong, Moon-Taeg; Jang, Seong-Joo; Choi, Nam-Gil; Han, Jae-Bok; Yang, Nam-Hee; Dong, Kyung-Rae; Chung, Woon-Kwan; Lee, Yun-Jong; Ryu, Young-Hwan; Choi, Sung-Hyun; Seong, Kyeong-Jeong

2014-01-01

This study examined whether scanning could be performed with minimum dose and minimum exposure to the patient after an attenuation correction. A Hoffman 3D Brain Phantom was used in BIO_40 and D_690 PET/CT scanners, and the CT dose for the equipment was classified as a low dose (minimum dose), medium dose (general dose for scanning) and high dose (dose with use of contrast medium) before obtaining the image at a fixed kilo-voltage-peak (kVp) and milliampere (mA) that were adjusted gradually in 17-20 stages. A PET image was then obtained to perform an attenuation correction based on an attenuation map before analyzing the dose difference. Depending on tube current in the range of 33-190 milliampere-second (mAs) when BIO_40 was used, a significant difference in the effective dose was observed between the minimum and the maximum mAs (p < 0.05). According to a Scheffe post-hoc test, the ratio of the minimum to the maximum of the effective dose was increased by approximately 5.26-fold. Depending on the change in the tube current in the range of 10-200 mA when D_690 was used, a significant difference in the effective dose was observed between the minimum and the maximum of mA (p < 0.05). The Scheffe posthoc test revealed a 20.5-fold difference. In conclusion, because effective exposure dose increases with increasing operating current, it is possible to reduce the exposure limit in a brain scan can be reduced if the CT dose can be minimized for a transmission scan.

Wood Energy Potential in Northwestern South Carolina

Treesearch

James W. McMinn

1986-01-01

The quantity of unused wood in an Ill-county area in northwestern South Carolina was projected to be more than 16 million tons annually. Wood that is unsuitable for products other than fuel amounts to nearly 9 million tons annually.The most likely energy demand by industrial plants that are good candidates for wood fuel systems is 1.5 million tons annually.Maximum...

Implied Maximum Dose Analysis of Standard Values of 25 Pesticides Based on Major Human Exposure Pathways

PubMed Central

Li, Zijian; Jennings, Aaron A.

2017-01-01

Worldwide jurisdictions are making efforts to regulate pesticide standard values in residential soil, drinking water, air, and agricultural commodity to lower the risk of pesticide impacts on human health. Because human may exposure to pesticides from many ways, such as ingestion, inhalation, and dermal contact, it is important to examine pesticide standards by considering all major exposure pathways. Analysis of implied maximum dose limits for commonly historical and current used pesticides was adopted in this study to examine whether worldwide pesticide standard values are enough to prevent human health impact or not. Studies show that only U.S. has regulated pesticides standard in the air. Only 4% of the total number of implied maximum dose limits is based on three major exposures. For Chlorpyrifos, at least 77.5% of the total implied maximum dose limits are above the acceptable daily intake. It also shows that most jurisdictions haven't provided pesticide standards in all major exposures yet, and some of the standards are not good enough to protect human health. PMID:29546224

Safety and tolerability of the first-in-class agent CPI-613 in combination with modified FOLFIRINOX in patients with metastatic pancreatic cancer: a single-centre, open-label, dose-escalation, phase 1 trial.

PubMed

Alistar, Angela; Morris, Bonny B; Desnoyer, Rodwige; Klepin, Heidi D; Hosseinzadeh, Keyanoosh; Clark, Clancy; Cameron, Amy; Leyendecker, John; D'Agostino, Ralph; Topaloglu, Umit; Boteju, Lakmal W; Boteju, Asela R; Shorr, Rob; Zachar, Zuzana; Bingham, Paul M; Ahmed, Tamjeed; Crane, Sandrine; Shah, Riddhishkumar; Migliano, John J; Pardee, Timothy S; Miller, Lance; Hawkins, Gregory; Jin, Guangxu; Zhang, Wei; Pasche, Boris

2017-06-01

Pancreatic cancer statistics are dismal, with a 5-year survival of less than 10%, and more than 50% of patients presenting with metastatic disease. Metabolic reprogramming is an emerging hallmark of pancreatic adenocarcinoma. CPI-613 is a novel anticancer agent that selectively targets the altered form of mitochondrial energy metabolism in tumour cells, causing changes in mitochondrial enzyme activities and redox status that lead to apoptosis, necrosis, and autophagy of tumour cells. We aimed to establish the maximum tolerated dose of CPI-613 when used in combination with modified FOLFIRINOX chemotherapy (comprising oxaliplatin, leucovorin, irinotecan, and fluorouracil) in patients with metastatic pancreatic cancer. In this single-centre, open-label, dose-escalation phase 1 trial, we recruited adult patients (aged ≥18 years) with newly diagnosed metastatic pancreatic adenocarcinoma from the Comprehensive Cancer Center of Wake Forest Baptist Medical Center (Winston-Salem, NC, USA). Patients had good bone marrow, liver and kidney function, and good performance status (Eastern Cooperative Oncology Group [ECOG] performance status 0-1). We studied CPI-613 in combination with modified FOLFIRINOX (oxaliplatin at 65 mg/m 2 , leucovorin at 400 mg/m 2 , irinotecan at 140 mg/m 2 , and fluorouracil 400 mg/m 2 bolus followed by 2400 mg/m 2 over 46 h). We applied a two-stage dose-escalation scheme (single patient and traditional 3+3 design). In the single-patient stage, one patient was accrued per dose level. The starting dose of CPI-613 was 500 mg/m 2 per day; the dose level was then escalated by doubling the previous dose if there were no adverse events worse than grade 2 within 4 weeks attributed as probably or definitely related to CPI-613. The traditional 3+3 dose-escalation stage was triggered if toxic effects attributed as probably or definitely related to CPI-613 were grade 2 or worse. The dose level for CPI-613 for the first cohort in the traditional dose-escalation stage was the same as that used in the last cohort of the single-patient dose-escalation stage. The primary objective was to establish the maximum tolerated dose of CPI-613 (as assessed by dose-limiting toxicities). This trial is registered with ClinicalTrials.gov, number NCT01835041, and is closed to recruitment. Between April 22, 2013, and Jan 8, 2016, we enrolled 20 patients. The maximum tolerated dose of CPI-613 was 500 mg/m 2 . The median number of treatment cycles given at the maximum tolerated dose was 11 (IQR 4-19). Median follow-up of the 18 patients treated at the maximum tolerated dose was 378 days (IQR 250-602). Two patients enrolled at a higher dose of 1000 mg/m 2 , and both had a dose-limiting toxicity. Two unexpected serious adverse events occurred, both for the first patient enrolled. Expected serious adverse events were: thrombocytopenia, anaemia, and lymphopenia (all for patient number 2; anaemia and lymphopenia were dose-limiting toxicities); hyperglycaemia (in patient number 7); hypokalaemia, hypoalbuminaemia, and sepsis (patient number 11); and neutropenia (patient number 20). No deaths due to adverse events were reported. For the 18 patients given the maximum tolerated dose, the most common grade 3-4 non-haematological adverse events were hyperglycaemia (ten [55%] patients), hypokalaemia (six [33%]), peripheral sensory neuropathy (five [28%]), diarrhoea (five [28%]), and abdominal pain (four [22%]). The most common grade 3-4 haematological adverse events were neutropenia (five [28%] of 18 patients), lymphopenia (five [28%]), anaemia (four [22%], and thrombocytopenia in three [17%]). Sensory neuropathy (all grade 1-3) was recorded in 17 (94%) of the 18 patients and was managed with dose de-escalation or discontinuation per standard of care. No patients died while on active treatment; 11 study participants died, with cause of death as terminal pancreatic cancer. Of the 18 patients given the maximum tolerated dose, 11 (61%) achieved an objective (complete or partial) response. A maximum tolerated dose of CPI-613 was established at 500 mg/m 2 when used in combination with modified FOLFIRINOX in patients with metastatic pancreatic cancer. The findings of clinical activity will require validation in a phase 2 trial. Comprehensive Cancer Center of Wake Forest Baptist Medical Center. Copyright © 2017 Elsevier Ltd. All rights reserved.

Efficacy and tolerability of treatment with single doses of diethylcarbamazine (DEC) and DEC plus albendazole (ABZ) for three consecutive years in lymphatic filariasis: a field study in India.

PubMed

Kshirsagar, Nilima A; Gogtay, N J; Garg, B S; Deshmukh, P R; Rajgor, D D; Kadam, V S; Thakur, P A; Gupta, A; Ingole, N S; Lazdins-Helds, J K

2017-10-01

Lymphatic filariasis (LF) affects 73 countries, causes morbidity and impedes socioeconomic development. We had found no difference in safety and micro (Mf) and macro filarial action of single-dose diethylcarbamazine (DEC) and DEC + albendazole (ABZ) in an F01 study done in India (year 2000). There was a programmatic need to evaluate safety and efficacy of multiple annual treatments (F02). Subjects (155) from the F01 study, meeting inclusion-exclusion criteria, were enrolled in F02 and treated with further two annual doses of DEC or DEC + ABZ. Efficacy was evaluated for Mf positivity by peripheral smear (PS) and nucleopore (NP) filter, circulating filarial antigen (CFA) and filarial dance sign (FDS) positivity and Mf count at yearly follow-up. Safety was assessed for 5 days after drug administration. Total of 139 subjects evaluated for efficacy (69 DEC and 70 DEC + ABZ group). Mf positivity prevalence declined progressively by 95% (PS), 66% (NP), and 95% (PS) and 86% (NP); CFA positivity prevalence declined by 15% and 9%; FDS by 100% each; Mf count declined by 75.5 and 76.9% with three annual treatment of DEC and DEC + ABZ, respectively. Addition of ABZ did not show any advantage over DEC given as three annual rounds for LF. DEC and DEC + ABZ were well tolerated. There was no correlation between result of CFA and FDS, (both claimed to be indicative of adult worm). Analysis of published studies and our data indicate that macrofilaricidal effect of DEC/DEC + ABZ may be seen in children and not adults, with three or more annual dosing.

Dosimetric Evaluation Between Megavoltage Cone-Beam Computed Tomography and Body Mass Index for Intracranial, Thoracic, and Pelvic Localization

DOE Office of Scientific and Technical Information (OSTI.GOV)

VanAntwerp, April E.; Raymond, Sarah M., E-mail: raymons9@ccf.org; Addington, Mark C.

2011-10-01

The aim of this study was to evaluate radiation dose for organs at risk (OAR) within the cranium, thorax, and pelvis from megavoltage cone-beam computed tomography (MV-CBCT). Using a clinical treatment planning system, CBCT doses were calculated from 60 patient datasets using 27.4 x 27.4 cm{sup 2} field size and 200{sup o} arc length. The body mass indices (BMIs) for these patients range from 17.2-48.4 kg/m{sup 2}. A total of 60 CBCT plans were created and calculated with heterogeneity corrections, with monitor units (MU) that varied from 8, 4, and 2 MU per plan. The isocenters of these plans weremore » placed at defined anatomical structures. The maximum dose, dose to the isocenter, and mean dose to the selected critical organs were analyzed. The study found that maximum and isocenter doses were weakly associated with BMI, but linearly associated with the total MU. Average maximum/isocenter doses in the cranium were 10.0 ({+-} 0.18)/7.0 ({+-} 0.08) cGy, 5.0 ({+-} 0.09)/3.5 ({+-} 0.05) cGy, and 2.5 ({+-} .04)/1.8 ({+-} 0.05) cGy for 8, 4, and 2 MU, respectively. Similar trends but slightly larger maximum/isocenter doses were found in the thoracic and pelvic regions. For the cranial region, the average mean doses with a total of 8 MU to the eye, lens, and brain were 9.7 ({+-} 0.12) cGy, 9.1 ({+-} 0.16) cGy, and 7.2 ({+-} 0.10) cGy, respectively. For the thoracic region, the average mean doses to the lung, heart, and spinal cord were 6.6 ({+-} 0.05) cGy, 6.9 ({+-} 1.2) cGy, and 4.7 ({+-} 0.8) cGy, respectively. For the pelvic region, the average mean dose to the femoral heads was 6.4 ({+-} 1.1) cGy. The MV-CBCT doses were linearly associated with the total MU but weakly dependent on patients' BMIs. Daily MV-CBCT has a cumulative effect on the total body dose and critical organs, which should be carefully considered for clinical impacts.« less

Daily radionuclide ingestion and internal radiation doses in Aomori prefecture, Japan.

PubMed

Ohtsuka, Yoshihito; Kakiuchi, Hideki; Akata, Naofumi; Takaku, Yuichi; Hisamatsu, Shun'ichi

2013-10-01

To assess internal annual dose in the general public in Aomori Prefecture, Japan, 80 duplicate cooked diet samples, equivalent to the food consumed over a 400-d period by one person, were collected from 100 volunteers in Aomori City and the village of Rokkasho during 2006–2010 and were analyzed for 11 radionuclides. To obtain average rates of ingestion of radionuclides, the volunteers were selected from among office, fisheries, agricultural, and livestock farm workers. Committed effective doses from ingestion of the diet over a 1-y period were calculated from the analytical results and from International Commission on Radiological Protection dose coefficients; for 40K, an internal effective dose rate from the literature was used. Fisheries workers had significantly higher combined internal annual dose than the other workers, possibly because of high rates of ingestion of marine products known to have high 210Po concentrations. The average internal dose rate, weighted by the numbers of households in each worker group in Aomori Prefecture, was estimated at 0.47 mSv y-1. Polonium-210 contributed 49% of this value. The sum of committed effective dose rates for 210Po, 210Pb, 228Ra, and 14C and the effective dose rate of 40K accounted for approximately 99% of the average internal dose rate.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pokhrel, D; Sood, S; Badkul, R

Purpose: To evaluate XVMC computed rib doses for peripherally located non-small-cell-lung tumors treated with SBRT following RTOG-0915 guidelines. Methods: Twenty patients with solitary peripherally located non-small-cell-lung tumors were treated using XVMC-based SBRT to 50–54Gy in 5−3 fractions, respectively, for PTV(V100%)=95%. Based on 4D-CT, ITV was delineated on MaximumIP images and organs-at-risk(OARs) including ribs were contoured on MeanIP images. Mean PTV(ITV+5mm uniform margin) was 46.1±38.7cc (range, 11.1–163.0cc). XVMC SBRT treatment plans were generated with a combination of non-coplanar 3D-conformal arcs/beams, and were delivered by Novalis-TX consisting of HD-MLCs and a 6MV-SRS(1000MU/min) beam, following RTOG-0915 criteria. XVMC rib maximum dose and dosemore » to <1cc, <5cc, <10cc were evaluated as a function of PTV, prescription dose and 3D-distance from tumor isocenter to the most proximal rib contour. Plans were re-computed using heterogeneity-corrected pencil-beam (PB-hete) algorithm utilizing identical beam geometry/MLC positions and MUs and subsequently compared to XVMC. Results: XVMC average maximum rib dose was 50.9±6.4Gy (range, 35.1–59.3Gy). XVMC mean rib dose to <1cc was 41.6±5.6Gy (range, 27.9–47.9Gy), <5cc was 31.2±7.3Gy (range, 10.6–43.1Gy), and <10cc was 21.2±8.7Gy (range, 1.1–36Gy), respectively. For the given prescription, correlation between PTV and rib doses to <5cc (p=0.005) and <10cc (p=0.018) was observed. 3D-distance from the tumor isocenter to the proximal rib contour strongly correlated with maximum rib dose (p=0.0001). PB-hete algorithm overestimated maximum rib dose and dose to <1cc, <5cc, and <10cc of ribs by 5%, 3%, 3%, and 3%, respectively. Conclusion: PB-hete overestimates ribs dose relative to XVMC. Since all the clinical XVMC plans were generated without compromising the target coverage (per RTOG-0915), almost all patient’s ribs doses were higher than the protocol guidelines. As expected, larger tumor size and proximity to ribs received higher absolute dose to ribs. Prospective observation is needed to determine if XVMC delivered rib doses correlates with patient symptoms including chest wall pain and/or rib fractures.« less

Emergency department patient knowledge concerning acetaminophen (paracetamol) in over-the-counter and prescription analgesics.

PubMed

Fosnocht, D; Taylor, J R; Caravati, E M

2008-04-01

This study was designed to evaluate patient knowledge of the acetaminophen (paracetamol) content of commonly used pain medications and the maximum daily recommended dose of acetaminophen. A prospective, convenience sample of emergency department patients were enrolled. Data were recorded using a standardised questionnaire over 4 months. 1009 patients were enrolled. 492 patients (49%) did not know if Tylenol contained acetaminophen (paracetamol). The majority (66-90%) of patients did not know if Lortab, Vicodin, Percocet, non-aspirin pain reliever, ibuprofen, Motrin, or Advil contained acetaminophen. 568 patients (56%) reported not knowing the maximum daily dose of acetaminophen and only 71 patients (7%) reported the correct daily dose. Patient knowledge of the acetaminophen content of commonly used analgesic medications and its maximum recommended daily dose is limited. This may contribute to unintentional repeated supratherapeutic ingestion (RSTI) of acetaminophen, or overdose.

Radiological Environmental Protection for PEP-II Ring High Luminosity Operation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Liu, James C.; Nakao, Noriaki; /SLAC

2006-08-16

Stanford Linear Accelerator Center (SLAC) is located in northern California, USA. Radiological environmental protection is one of the main elements of the radiation protection program. One of SLAC's accelerator facilities is B-Factory, whose PEP-II accelerator ring has been operating since 1997 and is being upgraded to higher luminosity operation. Four radiological issues associated with high luminosity operation up to CY2008 are re-evaluated: (1) annual doses in IR halls, (2) annual skyshine doses at site boundaries, (3) potential radioactive air releases, and (4) potential groundwater activation. This paper presents the skyshine doses and air emission doses to the Maximally Exposed Individualmore » (MEI) at SLAC site boundaries. The normal beam loss scenarios around PEP-II ring are presented first. In CY2008, the luminosity is 2 x 10{sup 34} cm{sup -2} s{sup -1}, and the stored current is 4.0-A for low-energy ring (LER ) and 2.2-A for high-energy ring (HER). The beam losses around PEP-II ring include those near injection region in IR10 and IR8 and those at collimators (e.g., HER collimators in IR12, LER collimators in IR4 and IR6). The beam losses in IR8 and IR10 (where injection into ring occurs) are further divided into septum, BAD (beam abort dump) and TD (tune-up dump), as well as apertures. The skyshine prompt dose rate distributions as a function of distance from an IR hall at four directions were calculated using the MARS15 Monte Carlo code. For skyshine dose to the MEI, the annual dose (7200 h/y occupancy) is calculated to be 2.9 mrem/y at Sand Hill Road (from e{sup -} losses in IR12 HER collimators) and 1.2 mrem/y at Horse Track Offices near IR6 (from e{sup +} losses in IR8, IR6 and IR4). These are lower than the SLAC skyshine limit of 5 mrem/y for any single facility within SLAC. Radionuclide productions in the air at the PEP-II IR10 were calculated using MARS15. Beam losses of 9-GeV electrons were assumed in three target cases: the copper TD, septum and BAD. Energy spectra of secondary particles of photons, neutrons, protons and pions in the IR10 air region were calculated. Radionuclide yields of {sup 11}C, {sup 13}N, {sup 15}O, {sup 3}H, {sup 7}Be and {sup 41}Ar were estimated using the obtained particle energy spectra, folded with the reaction cross sections. With certain operation and ventilation conditions, the annual air emission dose to the MEI at Sand Hill Road from e{sup -} losses in IR10 is calculated to be 0.004 mrem/y (7200 h/y occupancy). The annual dose to the MEI at Horse Track Offices is 0.002 mrem/y from e{sup +} losses in IR8, 0.003 mrem/y from IR6, and 0.025 mrem/y from IR4. The doses are dominated by {sup 13}N. Therefore, the EPA annual dose limit of 10 mrem/y for SLAC and the continuous ventilation monitoring limit of 0.1 mrem/y for each release point are not exceeded.« less

Reconstruction of Absorbed Doses to Fibroglandular Tissue of the Breast of Women undergoing Mammography (1960 to the Present)

PubMed Central

Thierry-Chef, Isabelle; Simon, Steven L.; Weinstock, Robert M.; Kwon, Deukwoo; Linet, Martha S.

2013-01-01

The assessment of potential benefits versus harms from mammographic examinations as described in the controversial breast cancer screening recommendations of the U.S. Preventive Task Force included limited consideration of absorbed dose to the fibroglandular tissue of the breast (glandular tissue dose), the tissue at risk for breast cancer. Epidemiological studies on cancer risks associated with diagnostic radiological examinations often lack accurate information on glandular tissue dose, and there is a clear need for better estimates of these doses. Our objective was to develop a quantitative summary of glandular tissue doses from mammography by considering sources of variation over time in key parameters including imaging protocols, x-ray target materials, voltage, filtration, incident air kerma, compressed breast thickness, and breast composition. We estimated the minimum, maximum, and mean values for glandular tissue dose for populations of exposed women within 5-year periods from 1960 to the present, with the minimum to maximum range likely including 90% to 95% of the entirety of the dose range from mammography in North America and Europe. Glandular tissue dose from a single view in mammography is presently about 2 mGy, about one-sixth the dose in the 1960s. The ratio of our estimates of maximum to minimum glandular tissue doses for average-size breasts was about 100 in the 1960s compared to a ratio of about 5 in recent years. Findings from our analysis provide quantitative information on glandular tissue doses from mammographic examinations which can be used in epidemiologic studies of breast cancer. PMID:21988547

Dosimetric verification of IMRT treatment planning using Monte Carlo simulations for prostate cancer

NASA Astrophysics Data System (ADS)

Yang, J.; Li, J.; Chen, L.; Price, R.; McNeeley, S.; Qin, L.; Wang, L.; Xiong, W.; Ma, C.-M.

2005-03-01

The purpose of this work is to investigate the accuracy of dose calculation of a commercial treatment planning system (Corvus, Normos Corp., Sewickley, PA). In this study, 30 prostate intensity-modulated radiotherapy (IMRT) treatment plans from the commercial treatment planning system were recalculated using the Monte Carlo method. Dose-volume histograms and isodose distributions were compared. Other quantities such as minimum dose to the target (Dmin), the dose received by 98% of the target volume (D98), dose at the isocentre (Diso), mean target dose (Dmean) and the maximum critical structure dose (Dmax) were also evaluated based on our clinical criteria. For coplanar plans, the dose differences between Monte Carlo and the commercial treatment planning system with and without heterogeneity correction were not significant. The differences in the isocentre dose between the commercial treatment planning system and Monte Carlo simulations were less than 3% for all coplanar cases. The differences on D98 were less than 2% on average. The differences in the mean dose to the target between the commercial system and Monte Carlo results were within 3%. The differences in the maximum bladder dose were within 3% for most cases. The maximum dose differences for the rectum were less than 4% for all the cases. For non-coplanar plans, the difference in the minimum target dose between the treatment planning system and Monte Carlo calculations was up to 9% if the heterogeneity correction was not applied in Corvus. This was caused by the excessive attenuation of the non-coplanar beams by the femurs. When the heterogeneity correction was applied in Corvus, the differences were reduced significantly. These results suggest that heterogeneity correction should be used in dose calculation for prostate cancer with non-coplanar beam arrangements.

FOREST-BGC, A general model of forest ecosystem processes for regional applications. II. Dynamic carbon allocation and nitrogen budgets.

PubMed

Running, Steven W.; Gower, Stith T.

1991-01-01

A new version of the ecosystem process model FOREST-BGC is presented that uses stand water and nitrogen limitations to alter the leaf/root/stem carbon allocation fraction dynamically at each annual iteration. Water deficit is defined by integrating a daily soil water deficit fraction annually. Current nitrogen limitation is defined relative to a hypothetical optimum foliar N pool, computed as maximum leaf area index multiplied by maximum leaf nitrogen concentration. Decreasing availability of water or nitrogen, or both, reduces the leaf/root carbon partitioning ratio. Leaf and root N concentrations, and maximum leaf photosynthetic capacity are also redefined annually as functions of nitrogen availability. Test simulations for hypothetical coniferous forests were performed for Madison, WI and Missoula, MT, and showed simulated leaf area index ranging from 4.5 for a control stand at Missoula, to 11 for a fertilized stand at Madison, with Year 50 stem carbon biomasses of 31 and 128 Mg ha(-1), respectively. Total nitrogen incorporated into new tissue ranged from 34 kg ha(-1) year(-1) for the unfertilized Missoula stand, to 109 kg ha(-1) year(-1) for the fertilized Madison stand. The model successfully showed dynamic annual carbon partitioning controlled by water and nitrogen limitations.

Estimation of annual occupational effective doses from external ionizing radiation at medical institutions in Kenya

NASA Astrophysics Data System (ADS)

Korir, Geoffrey; Wambani, Jeska; Korir, Ian

2011-04-01

This study details the distribution and trends of doses due to occupational radiation exposure among radiation workers from participating medical institutions in Kenya, where monthly dose measurements were collected for a period of one year ranging from January to December in 2007. A total of 367 medical radiation workers were monitored using thermoluminescent dosemeters. They included radiologists (27%), oncologists (2%), dentists (4%), Physicists (5%), technologists (45%), nurses (4%), film processor technicians (3%), auxiliary staff (4%), and radiology office staff (5%). The average annual effective dose of all categories of staff was found to range from 1.19 to 2.52 mSv. This study formed the initiation stage of wider, comprehensive and more frequent monitoring of occupational radiation exposures and long-term investigations into its accumulation patterns in our country.

Assessment of natural radionuclides and its radiological hazards from tiles made in Nigeria

NASA Astrophysics Data System (ADS)

Joel, E. S.; Maxwell, O.; Adewoyin, O. O.; Ehi-Eromosele, C. O.; Embong, Z.; Saeed, M. A.

2018-03-01

Activity concentration of 10 different brands of tiles made in Nigeria were analyzed using High purity Germanium gamma detector and its hazard indices such as absorbed dose rate, radium equivalent activity, external Hazard Index (Hex), internal Hazard Index (Hin), Annual Effective Dose (mSv/y), Gamma activity Index (Iγ) and Alpha Index (Iα) were determined. The result showed that the average activity concentrations of radionuclides (226Ra, 232Th and 40K) content are within the recommended limit. The average radium equivalent is within the recommended limit of 370 Bq/kg. The result obtained further showed that the mean values for the absorbed dose rate (D), external and internal hazard index, the annual effective dose (AEDR) equivalent, gamma activity index and Alpha Index were: 169.22 nGyh-1, 0.95 and 1.14, 1.59 mSv/y, 1.00 Sv yr-1 and 0.34 respectively. The result established that radiological hazards such as absorbed dose rate, internal hazard, annual effective dose rate, gamma activity index and Alpha Index for some samples are found to be slightly close or above international recommended values. The result for the present study was compared with tiles sample from others countries, it was observed that the concentration of tiles made in Nigeria and other countries are closer, however recommends proper radiation monitoring for some tiles made in Nigeria before usage due to the long term health effect.

Spatial correlation in precipitation trends in the Brazilian Amazon

NASA Astrophysics Data System (ADS)

Buarque, Diogo Costa; Clarke, Robin T.; Mendes, Carlos Andre Bulhoes

2010-06-01

A geostatistical analysis of variables derived from Amazon daily precipitation records (trends in annual precipitation totals, trends in annual maximum precipitation accumulated over 1-5 days, trend in length of dry spell, trend in number of wet days per year) gave results that are consistent with those previously reported. Averaged over the Brazilian Amazon region as a whole, trends in annual maximum precipitations were slightly negative, the trend in the length of dry spell was slightly positive, and the trend in the number of wet days in the year was slightly negative. For trends in annual maximum precipitation accumulated over 1-5 days, spatial correlation between trends was found to extend up to a distance equivalent to at least half a degree of latitude or longitude, with some evidence of anisotropic correlation. Time trends in annual precipitation were found to be spatially correlated up to at least ten degrees of separation, in both W-E and S-N directions. Anisotropic spatial correlation was strongly evident in time trends in length of dry spell with much stronger evidence of spatial correlation in the W-E direction, extending up to at least five degrees of separation, than in the S-N. Because the time trends analyzed are shown to be spatially correlated, it is argued that methods at present widely used to test the statistical significance of climate trends over time lead to erroneous conclusions if spatial correlation is ignored, because records from different sites are assumed to be statistically independent.

Bolus-dependent dosimetric effect of positioning errors for tangential scalp radiotherapy with helical tomotherapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lobb, Eric, E-mail: eclobb2@gmail.com

2014-04-01

The dosimetric effect of errors in patient position is studied on-phantom as a function of simulated bolus thickness to assess the need for bolus utilization in scalp radiotherapy with tomotherapy. A treatment plan is generated on a cylindrical phantom, mimicking a radiotherapy technique for the scalp utilizing primarily tangential beamlets. A planning target volume with embedded scalplike clinical target volumes (CTVs) is planned to a uniform dose of 200 cGy. Translational errors in phantom position are introduced in 1-mm increments and dose is recomputed from the original sinogram. For each error the maximum dose, minimum dose, clinical target dose homogeneitymore » index (HI), and dose-volume histogram (DVH) are presented for simulated bolus thicknesses from 0 to 10 mm. Baseline HI values for all bolus thicknesses were in the 5.5 to 7.0 range, increasing to a maximum of 18.0 to 30.5 for the largest positioning errors when 0 to 2 mm of bolus is used. Utilizing 5 mm of bolus resulted in a maximum HI value of 9.5 for the largest positioning errors. Using 0 to 2 mm of bolus resulted in minimum and maximum dose values of 85% to 94% and 118% to 125% of the prescription dose, respectively. When using 5 mm of bolus these values were 98.5% and 109.5%. DVHs showed minimal changes in CTV dose coverage when using 5 mm of bolus, even for the largest positioning errors. CTV dose homogeneity becomes increasingly sensitive to errors in patient position as bolus thickness decreases when treating the scalp with primarily tangential beamlets. Performing a radial expansion of the scalp CTV into 5 mm of bolus material minimizes dosimetric sensitivity to errors in patient position as large as 5 mm and is therefore recommended.« less

Impact of head and neck cancer adaptive radiotherapy to spare the parotid glands and decrease the risk of xerostomia.

PubMed

Castelli, Joel; Simon, Antoine; Louvel, Guillaume; Henry, Olivier; Chajon, Enrique; Nassef, Mohamed; Haigron, Pascal; Cazoulat, Guillaume; Ospina, Juan David; Jegoux, Franck; Benezery, Karen; de Crevoisier, Renaud

2015-01-09

Large anatomical variations occur during the course of intensity-modulated radiation therapy (IMRT) for locally advanced head and neck cancer (LAHNC). The risks are therefore a parotid glands (PG) overdose and a xerostomia increase. The purposes of the study were to estimate: - the PG overdose and the xerostomia risk increase during a "standard" IMRT (IMRTstd); - the benefits of an adaptive IMRT (ART) with weekly replanning to spare the PGs and limit the risk of xerostomia. Fifteen patients received radical IMRT (70 Gy) for LAHNC. Weekly CTs were used to estimate the dose distributions delivered during the treatment, corresponding either to the initial planning (IMRTstd) or to weekly replanning (ART). PGs dose were recalculated at the fraction, from the weekly CTs. PG cumulated doses were then estimated using deformable image registration. The following PG doses were compared: pre-treatment planned dose, per-treatment IMRTstd and ART. The corresponding estimated risks of xerostomia were also compared. Correlations between anatomical markers and dose differences were searched. Compared to the initial planning, a PG overdose was observed during IMRTstd for 59% of the PGs, with an average increase of 3.7 Gy (10.0 Gy maximum) for the mean dose, and of 8.2% (23.9% maximum) for the risk of xerostomia. Compared to the initial planning, weekly replanning reduced the PG mean dose for all the patients (p<0.05). In the overirradiated PG group, weekly replanning reduced the mean dose by 5.1 Gy (12.2 Gy maximum) and the absolute risk of xerostomia by 11% (p<0.01) (30% maximum). The PG overdose and the dosimetric benefit of replanning increased with the tumor shrinkage and the neck thickness reduction (p<0.001). During the course of LAHNC IMRT, around 60% of the PGs are overdosed of 4 Gy. Weekly replanning decreased the PG mean dose by 5 Gy, and therefore by 11% the xerostomia risk.

Comparison of dose volume parameters evaluated using three forward planning – optimization techniques in cervical cancer brachytherapy involving two applicators

PubMed Central

Basu-Roy, Somapriya; Kar, Sanjay Kumar; Das, Sounik; Lahiri, Annesha

2017-01-01

Purpose This study is intended to compare dose-volume parameters evaluated using different forward planning- optimization techniques, involving two applicator systems in intracavitary brachytherapy for cervical cancer. It looks for the best applicator-optimization combination to fulfill recommended dose-volume objectives in different high-dose-rate (HDR) fractionation schedules. Material and methods We used tandem-ring and Fletcher-style tandem-ovoid applicator in same patients in two fractions of brachytherapy. Six plans were generated for each patient utilizing 3 forward optimization techniques for each applicator used: equal dwell weight/times (‘no optimization’), ‘manual dwell weight/times’, and ‘graphical’. Plans were normalized to left point A and dose of 8 Gy was prescribed. Dose volume and dose point parameters were compared. Results Without graphical optimization, maximum width and thickness of volume enclosed by 100% isodose line, dose to 90%, and 100% of clinical target volume (CTV); minimum, maximum, median, and average dose to both rectum and bladder are significantly higher with Fletcher applicator. Even if it is done, dose to both points B, minimum dose to CTV, and treatment time; dose to 2 cc (D2cc) rectum and rectal point etc.; D2cc, minimum, maximum, median, and average dose to sigmoid colon; D2cc of bladder remain significantly higher with this applicator. Dose to bladder point is similar (p > 0.05) between two applicators, after all optimization techniques. Conclusions Fletcher applicator generates higher dose to both CTV and organs at risk (2 cc volumes) after all optimization techniques. Dose restriction to rectum is possible using graphical optimization only during selected HDR fractionation schedules. Bladder always receives dose higher than recommended, and 2 cc sigmoid colon always gets permissible dose. Contrarily, graphical optimization with ring applicators fulfills all dose volume objectives in all HDR fractionations practiced. PMID:29204164

Evaluation of annual effective dose from indoor radon concentration in Eastern Province, Dammam, Saudi Arabia

NASA Astrophysics Data System (ADS)

Abuelhia, E.

2017-11-01

The aim of this study is to determine the indoor radon concentration and to evaluate the annual effective dose received by the inhabitants in Dammam, Al-Khobar, and compare it with new premises built at university of dammam. The research has been carried out by using active detection method; Electronic Radon Detector (RAD-7) a solid state α-detector with its special accessories. The indoor radon concentration measured varies from 10.2 Bqm-3 to 25.8 Bqm-3 with an average value of 18.8 Bqm-3 and 19.7 Bqm-3 to 23.5 Bqm-3 with an average value of 21.7 Bqm-3, in Dammam and Al-khobar dwellings, respectively. In university of dammam the radon concentration varies from 7.4 Bqm-3 to 15.8 Bqm-3 with an average value of 9.02 Bqm-3. The values of annual effective doses were found to be 0.47mSv/y, 0.55mSv/y, and 0.23mSv/y, in Dammam, Al-khobar and university new premises, respectively. The average radon concentration in the old dwellings was two times compared to that in the new premises and it was 25.4 Bqm-3 lower than the world average value of 40 Bqm-3 reported by the UNSCEAR. The annual effective doses in the old dwellings was found to be (0.55mSv/y) two times the doses received at the new premises, and below the world wide average of 1.15mSv/y reported by ICRP (2010). The indoor radon concentration in the study region is safe as far as health hazard is concerned.

Soil and Water Assessment Tool model predictions of annual maximum pesticide concentrations in high vulnerability watersheds.

PubMed

Winchell, Michael F; Peranginangin, Natalia; Srinivasan, Raghavan; Chen, Wenlin

2018-05-01

Recent national regulatory assessments of potential pesticide exposure of threatened and endangered species in aquatic habitats have led to increased need for watershed-scale predictions of pesticide concentrations in flowing water bodies. This study was conducted to assess the ability of the uncalibrated Soil and Water Assessment Tool (SWAT) to predict annual maximum pesticide concentrations in the flowing water bodies of highly vulnerable small- to medium-sized watersheds. The SWAT was applied to 27 watersheds, largely within the midwest corn belt of the United States, ranging from 20 to 386 km 2 , and evaluated using consistent input data sets and an uncalibrated parameterization approach. The watersheds were selected from the Atrazine Ecological Exposure Monitoring Program and the Heidelberg Tributary Loading Program, both of which contain high temporal resolution atrazine sampling data from watersheds with exceptionally high vulnerability to atrazine exposure. The model performance was assessed based upon predictions of annual maximum atrazine concentrations in 1-d and 60-d durations, predictions critical in pesticide-threatened and endangered species risk assessments when evaluating potential acute and chronic exposure to aquatic organisms. The simulation results showed that for nearly half of the watersheds simulated, the uncalibrated SWAT model was able to predict annual maximum pesticide concentrations within a narrow range of uncertainty resulting from atrazine application timing patterns. An uncalibrated model's predictive performance is essential for the assessment of pesticide exposure in flowing water bodies, the majority of which have insufficient monitoring data for direct calibration, even in data-rich countries. In situations in which SWAT over- or underpredicted the annual maximum concentrations, the magnitude of the over- or underprediction was commonly less than a factor of 2, indicating that the model and uncalibrated parameterization approach provide a capable method for predicting the aquatic exposure required to support pesticide regulatory decision making. Integr Environ Assess Manag 2018;14:358-368. © 2017 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals, Inc. on behalf of Society of Environmental Toxicology & Chemistry (SETAC). © 2017 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals, Inc. on behalf of Society of Environmental Toxicology & Chemistry (SETAC).

Potentiometric surface in the Central Oklahoma (Garber-Wellington) aquifer, Oklahoma, 2009

USGS Publications Warehouse

Mashburn, Shana L.; Magers, Jessica

2011-01-01

A study of the hydrogeology of the Central Oklahoma aquifer was started in 2008 to provide the Oklahoma Water Resources Board (OWRB) hydrogeologic data and a groundwater flow model that can be used as a tool to help manage the aquifer. The 1973 Oklahoma water law requires the OWRB to do hydrologic investigations of Oklahoma's aquifers (termed 'groundwater basins') and to determine amounts of water that may be withdrawn by permitted water users. 'Maximum annual yield' is a term used by OWRB to describe the total amount of water that can be withdrawn from a specific aquifer in any year while allowing a minimum 20-year life of the basin (Oklahoma Water Resources Board, 2010). Currently (2010), the maximum annual yield has not been determined for the Central Oklahoma aquifer. Until the maximum annual yield determination is made, water users are issued a temporary permit by the OWRB for 2 acre-feet/acre per year. The objective of the study, in cooperation with the Oklahoma Water Resources Board, was to study the hydrogeology of the Central Oklahoma aquifer to provide information that will enable the OWRB to determine the maximum annual yield of the aquifer based on different proposed management plans. Groundwater flow models are typically used by the OWRB as a tool to help determine the maximum annual yield. This report presents the potentiometric surface of the Central Oklahoma aquifer based on water-level data collected in 2009 as part of the current (2010) hydrologic study. The U.S. Geological Survey (USGS) Hydrologic Investigations Atlas HA-724 by Christenson and others (1992) presents the 1986-87 potentiometric-surface map. This 1986-87 potentiometric-surface map was made as part of the USGS National Water-Quality Assessment pilot project for the Central Oklahoma aquifer that examined the geochemical and hydrogeological processes operating in the aquifer. An attempt was made to obtain water-level measurements for the 2009 potentiometric-surface map from the wells used for the 1986-87 potentiometric-surface map. Well symbols with circles on the 2009 potentiometric-surface map (fig. 1) indicate wells that were used for the 1986-87 potentiometric-surface map.

Individual external doses below the lowest reference level of 1 mSv per year five years after the 2011 Fukushima nuclear accident among all children in Soma City, Fukushima: A retrospective observational study

PubMed Central

Murakami, Michio; Nomura, Shuhei; Morita, Tomohiro; Nishikawa, Yoshitaka; Leppold, Claire; Kato, Shigeaki; Kami, Masahiro

2017-01-01

After the 2011 Fukushima Daiichi nuclear power plant accident, little information has been available on individual doses from external exposure among residents living in radioactively contaminated areas near the nuclear plant; in the present study we evaluated yearly changes in the doses from external exposure after the accident and the effects of decontamination on external exposure. This study considered all children less than 16 years of age in Soma City, Fukushima who participated in annual voluntary external exposure screening programs during the five years after the accident (n = 5,363). In total, 14,405 screening results were collected. The median participant age was eight years. The geometric mean levels of annual additional doses from external exposure attributable to the Fukushima accident, decreased each year: 0.60 mSv (range: not detectable (ND)–4.29 mSv), 0.37 mSv (range: ND–3.61 mSv), 0.22 mSv (range: ND–1.44 mSv), 0.20 mSv (range: ND–1.87 mSv), and 0.17 mSv (range: ND–0.85 mSv) in 2011, 2012, 2013, 2014, and 2015, respectively. The proportion of residents with annual additional doses from external exposure of more than 1 mSv dropped from 15.6% in 2011 to zero in 2015. Doses from external exposure decreased more rapidly than those estimated from only physical decay, even in areas without decontamination (which were halved in 395 days from November 15, 2011), presumably due to the weathering effects. While the ratios of geometric mean doses immediately after decontamination to before were slightly lower than those during the same time in areas without decontamination, annual additional doses reduced by decontamination were small (0.04–0.24 mSv in the year of immediately after decontamination was completed). The results of this study showed that the levels of external exposure among Soma residents less than 16 years of age decreased during the five years after the Fukushima Daiichi nuclear power plant accident. Decontamination had only limited and temporal effects on reducing individual external doses. PMID:28235009

The Global Programme to Eliminate Lymphatic Filariasis: History and achievements with special reference to annual single-dose treatment with diethylcarbamazine in Samoa and Fiji.

PubMed

Kimura, Eisaku

2011-03-01

Diethylcarbamazine (DEC), first introduced in 1947, was shown to have strong efficacy and safety for treatment of human lymphatic filariasis, which is caused mostly by a species Wuchereria bancrofti. Many studies to optimize the dosage and treatment schedule of DEC followed, and, based on the results, control programs with various regimens were implemented in different endemic areas/countries. By the mid 1970s, with endorsement by the WHO Expert Committee on Filariasis (3rd report, 1974), the standard DEC regimen for W. bancrofti infection in mass treatment had been established in principle: a total dose of 72 mg/kg of body weight given in 12 divided doses, once weekly or monthly, at 6 mg/kg each. Not long after the committee report, the efficacy of annual single-dose treatment at 6 mg/kg, which is only one twelfth of the WHO-recommended dose in a year, was reported effective in French Polynesia (study period: 1973-78), and later in Samoa (study period: 1979-81). These results were published between 1978 and 1985 in the Bulletin of WHO but received little attention. In the mid 1980s, the efficacy of ivermectin, the first-choice drug for onchocerciasis, against lymphatic filariae came to light. Since the effect at a single dose was remarkable, and often better than DEC, it was predicted that the newly introduced drug would replace DEC. Treatment experiments with ivermectin increased quickly in number. Meanwhile, annual single-dose mass drug administration (MDA) with DEC at 6 mg/kg was under scrutiny in Samoa and Fiji. In the early 1990s, the Samoan study, which covered the entire population of 160,000 with 3 annual MDAs, reported a significant reduction in microfilaria (mf) prevalence and mean mf density, while in Fiji, the efficacy of 5 rounds of annual MDA (total dose, 30 mg/kg) was shown to be as effective as 28 multi-dose MDA spread over 2 years (6 weekly plus 22 monthly treatments at 5 mg/kg; total dose, 140 mg/kg). Several additional studies carried out in Samoa in relation to the annual single-dose MDAs revealed that low density mf carriers, who have a very low mf count of 1-20/ml of venous blood, could not play a significant role in filariasis transmission.From around 1990, studies on spaced low-dose DEC treatments and various types of combination chemotherapy with DEC and ivermectin increased. Albendazole, a well-known anti-intestinal helminths agent, was later added to the combination. The main findings of these studies with W. bancrofti are: (i) a single dose of DEC at 6 mg/kg reduced mean mf density by ca. 90% 1 year after treatment; (ii) the same dose could damage/kill adult worms; (iii) a single dose of ivermectin at ca. 400 µg/kg was more effective than DEC in reducing mf density during the first year and was similarly or less effective in the second year; (iv) ivermectin probably could not kill adult worms; (v) a single combined dose of albendazole (400 mg) and DEC (6 mg/kg) was effective to reduce mf density by 85 to nearly 100% 12-24 months after treatment; and (vi) ivermectin or albendazole included in the combination chemotherapy produced "beyond-filariasis" benefits: clearance/reduction of intestinal helminths, and, additionally, in the case of ivermectin, skin-dwelling ectoparasites.The Global Programme to Eliminate Lymphatic Filariasis (GPELF) started its worldwide activities in 2000, with the target of elimination by 2020. The basic strategy is to conduct annual single-dose MDAs for 4-6 years. In 2000-2007, a minimum of 570 million individuals were treated in 48 of 83 endemic countries. The drugs used are DEC 6 mg/kg plus albendazole 400 mg in most countries, or ivermectin 200-400 µg/kg plus albendazole 400 mg particularly in onchocerciasis endemic countries in Africa. (MDAs with DEC alone had been used in India.)The GPELF achieved impressive results in terms of parasitological cure/improvement, clinical benefits, social and economic impacts, etc. However, the most impressive result of all was the programme's success in mobilizing hundreds of millions of local people, who not only took drugs but many of them actively supported MDAs as drug distributors and volunteers. Beyond filariasis, the role people can play in supplementing rural health services is now a topic of discussion and a source of hope for a new sustainable system.

A Budget Impact Model of Hemophilia Bypassing Agent Prophylaxis Relative to Recombinant Factor VIIa On-Demand.

PubMed

Mehta, Darshan A; Oladapo, Abiola O; Epstein, Joshua D; Novack, Aaron R; Neufeld, Ellis J; Hay, Joel W

2016-02-01

Hemophilia patients use factor-clotting concentrates (factor VIII for hemophilia A and factor IX for hemophilia B) for improved blood clotting. These products are used to prevent or stop bleeding episodes. However, some hemophilia patients develop inhibitors (i.e., the patient's immune system develops antibodies against these factor concentrates). Hence, these patients do not respond well to the factor concentrates. A majority of hemophilia patients with inhibitors are managed on-demand with the following bypassing agents: recombinant factor VIIa (rFVIIa) and activated prothrombin complex concentrate (aPCC). The recently published U.S. registries Dosing Observational Study in Hemophilia (DOSE) and Hemostasis and Thrombosis Research Society (HTRS) reported higher rFVIIa on-demand use for bleed management than previously described. To estimate aPCC and rFVIIa prophylaxis costs relative to rFVIIa on-demand treatment cost based on rFVIIa doses reported in U.S. registries. A literature-based cost model was developed assuming a base case on-demand annual bleed rate (ABR) of 28.7 per inhibitor patient, which was taken from a randomized phase 3 clinical trial. The doses for rFVIIa on-demand were taken from the median dose per bleed reported by the DOSE and HTRS registries. Model inputs for aPCC and rFVIIa prophylaxis (i.e., dosing and efficacy) were derived from respective randomized clinical trials. Cost analysis was from the U.S. payer perspective, and only direct drug costs were considered. The drug cost was based on the Medicare Part B 2014 average sale price (ASP). Two-way sensitivity and threshold analyses were performed by simultaneously varying on-demand ABR, prophylaxis efficacy, and unit drug cost. In addition to studying relative costs associated with on-demand and prophylaxis treatments, relative cost per bleeding episode avoided were also calculated for aPCC and rFVIIa prophylaxis treatments. The prophylaxis efficacy reported in the trials were used to determine the number of bleeding episodes avoided. Based on the median on-demand dose of 695 mcg per kg per bleed, reported by the DOSE registry, the annual rFVIIa on-demand cost was $34,009 per kg of body weight. The annual rFVIIa on-demand cost was $22,020 per kg of body weight when the median dose of 450 mcg per kg per bleed reported by the HTRS registry was considered. The annual cost rose to $38,461 per kg of body weight when the rFVIIa on-demand dose of 786 mcg per kg per bleed among patients infusing an initial dose ≥ 250 mcg per kg was considered. The aPCC (85 units per kg per every other day) and rFVIIa (90 mcg per kg per every day) annual prophylaxis costs were $26,536 and $60,700, respectively. Also, aPCC and rFVIIa prophyaxis treatments were estimated to prevent a total of 20.8 and 12.9 annual bleeding episodes, respectively. When compared with the on-demand dose of 695 mcg per kg per bleed (DOSE registry), the annual aPCC and rFVIIa prophylaxis costs were 21.9% lower and 78.4% higher, respectively. Additionally, aPCC prophylaxis saved $360 per kg for each bleeding episode avoided. rFVIIa prophylaxis cost $2,066 per kg for each bleeding episode avoided. Compared with the on-demand dose of 450 mcg per kg per bleed (HTRS registry), aPCC and rFVIIa prophylaxis costs were 20.5% and 174.9% higher, respectively. In this case, aPCC and rFVIIa prophylaxis treatment costs were $217 per kg and $2,995 per kg, respectively, for each bleeding episode avoided. aPCC and rFVIIa prophylaxis costs were 31.0% lower and 57.8% higher, respectively, when compared with the rFVIIa on-demand dose of 786 mcg per kg per bleed, among patients infusing an initial dose ≥ 250 mcg per kg (HTRS registry). In this case, aPCC prophylaxis saved $573 per kg for each bleeding episode avoided, while rFVIIa prophylaxis costs $1,724 per kg for each bleeding episode avoided. Results of the 2-way sensitivity analyses were robust in the majority of the scenarios considered. aPCC prophylaxis may be cost saving for managing hemophilia patients with inhibitors who bleed frequently and infuse significant quantities of rFVIIa on-demand.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yeslbagg, Y. Ue.; Kuecuekoemeroglu, A.; Kurnaz, A.

Indoor radon studies have been conducted in Artvin, Eastern alack sea region of Turkey using SSNTD type nuclear track detector (CR-39). Radon measurements were done for 4 seasons in 73 dwellings, selected as uniformly distributed as possible. The radon concentrations vary from 21 aq m{sup -3} to 321 aq m{sup -3} with the annual mean concentration of 132 aq m{sup -3} for Artvin. Seasonal variation indoor radon shows high in winter low values in summer. The resulting estimated annual effective dose-equivalent due to inhalation of radon for inhabitants is 3.32 mSv y{sup -1} and the total annual effective dose liesmore » in the range of the action level (3-10 mSv y{sup -1}) recommended by the ICRP.« less

26 CFR 1.457-4 - Annual deferrals, deferral limitations, and deferral agreements under eligible plans.

Code of Federal Regulations, 2010 CFR

2010-04-01

... the next, so that in any single year an employee may have a maximum of four weeks' vacation time. At... agreement providing for the deferral), the value of any unused vacation time from the prior year in excess... amount is the lesser of two times the basic annual limitation ($30,000) or the sum of the basic annual...

26 CFR 1.457-4 - Annual deferrals, deferral limitations, and deferral agreements under eligible plans.

Code of Federal Regulations, 2011 CFR

2011-04-01

... the next, so that in any single year an employee may have a maximum of four weeks' vacation time. At... agreement providing for the deferral), the value of any unused vacation time from the prior year in excess... amount is the lesser of two times the basic annual limitation ($30,000) or the sum of the basic annual...

5 CFR 575.507 - What is the maximum extended assignment incentive that may be paid for a period of service?

Code of Federal Regulations, 2010 CFR

2010-01-01

... greater of— (1) An amount equal to 25 percent of the annual rate of basic pay of the employee at the... periods equals 546 days, and 546 days divided by 365 days equals 1.50 years. ... rate employees who do not have a scheduled annual rate of basic pay, the annual rate in paragraph (a...

SU-F-BRE-16: VMAT Commissioning and Quality Assurance (QA) of An Elekta Synergy-STM Linac Using ICOM Test HarnessTM

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nguyen, A; Ironwood CRC, Phoenix, AZ; Rajaguru, P

2014-06-15

Purpose: To establish a set of tests based on the iCOM software that can be used to commission and perform periodic QA of VMAT delivery on the Elekta Synergy-S, commonly known as the Beam Modulator (BM). Methods: iCOM is used to create and deliver customized treatment fields to characterize the system in terms of 1) MLC positioning accuracy under static and dynamic delivery with full gantry rotation, 2) MLC positioning with known errors, 3) Maximum dose rate, 4) Maximum MLC speed, 5) Maximum gantry speed, 6) Synchronization: gantry speed versus dose rate, and 7) Synchronization: MLC speed versus dose rate.more » The resulting images were captured on the iView GT and exported in DICOM format to Dosimetry Check™ system for visual and quantitative analysis. For the initial commissioning phase, the system tests described should be supplemented with extensive patient QAs covering all clinically relevant treatment sites. Results: The system performance test suite showed that on our Synergy-S, MLC positioning was accurate under both static and dynamic deliveries. Intentional errors of 1 mm were also easily identified on both static and dynamic picket fence tests. Maximum dose rate was verified with stop watch to be consistently between 475-480 MU/min. Maximum gantry speed and MLC speed were 5.5 degree/s and 2.5 cm/s respectively. After accounting for beam flatness, both synchronization tests, gantry versus dose rate and MLC speed versus dose rate, were successful as the fields were uniform across the strips and there were no obvious cold/hot spots. Conclusion: VMAT commissioning and quality assurance should include machine characterization tests in addition to patient QAs. Elekta iCOM is a valuable tool for the design of customized VMAT field with specific MU, MLC leaf positions, dose rate, and indirect control of MLC and gantry speed at each of its control points.« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pokharel, S; Rana, S

Purpose: purpose of this study is to evaluate the effect of grid size in Eclipse AcurosXB dose calculation algorithm for SBRT lung. Methods: Five cases of SBRT lung previously treated have been chosen for present study. Four of the plans were 5 fields conventional IMRT and one was Rapid Arc plan. All five cases have been calculated with five grid sizes (1, 1.5, 2, 2.5 and 3mm) available for AXB algorithm with same plan normalization. Dosimetric indices relevant to SBRT along with MUs and time have been recorded for different grid sizes. The maximum difference was calculated as a percentagemore » of mean of all five values. All the plans were IMRT QAed with portal dosimetry. Results: The maximum difference of MUs was within 2%. The time increased was as high as 7 times from highest 3mm to lowest 1mm grid size. The largest difference of PTV minimum, maximum and mean dose were 7.7%, 1.5% and 1.6% respectively. The highest D2-Max difference was 6.1%. The highest difference in ipsilateral lung mean, V5Gy, V10Gy and V20Gy were 2.6%, 2.4%, 1.9% and 3.8% respectively. The maximum difference of heart, cord and esophagus dose were 6.5%, 7.8% and 4.02% respectively. The IMRT Gamma passing rate at 2%/2mm remains within 1.5% with at least 98% points passing with all grid sizes. Conclusion: This work indicates the lowest grid size of 1mm available in AXB is not necessarily required for accurate dose calculation. The IMRT passing rate was insignificant or not observed with the reduction of grid size less than 2mm. Although the maximum percentage difference of some of the dosimetric indices appear large, most of them are clinically insignificant in absolute dose values. So we conclude that 2mm grid size calculation is best compromise in light of dose calculation accuracy and time it takes to calculate dose.« less

Variation of maximum tree height and annual shoot growth of Smith fir at various elevations in the Sygera Mountains, southeastern Tibetan Plateau.

PubMed

Wang, Yafeng; Čufar, Katarina; Eckstein, Dieter; Liang, Eryuan

2012-01-01

Little is known about tree height and height growth (as annual shoot elongation of the apical part of vertical stems) of coniferous trees growing at various altitudes on the Tibetan Plateau, which provides a high-elevation natural platform for assessing tree growth performance in relation to future climate change. We here investigated the variation of maximum tree height and annual height increment of Smith fir (Abies georgei var. smithii) in seven forest plots (30 m×40 m) along two altitudinal transects between 3,800 m and 4,200/4,390 m above sea level (a.s.l.) in the Sygera Mountains, southeastern Tibetan Plateau. Four plots were located on north-facing slopes and three plots on southeast-facing slopes. At each site, annual shoot growth was obtained by measuring the distance between successive terminal bud scars along the main stem of 25 trees that were between 2 and 4 m high. Maximum/mean tree height and mean annual height increment of Smith fir decreased with increasing altitude up to the tree line, indicative of a stress gradient (the dominant temperature gradient) along the altitudinal transect. Above-average mean minimum summer (particularly July) temperatures affected height increment positively, whereas precipitation had no significant effect on shoot growth. The time series of annual height increments of Smith fir can be used for the reconstruction of past climate on the southeastern Tibetan Plateau. In addition, it can be expected that the rising summer temperatures observed in the recent past and anticipated for the future will enhance Smith fir's growth throughout its altitudinal distribution range.

Global Analysis of Empirical Relationships Between Annual Climate and Seasonality of NDVI

NASA Technical Reports Server (NTRS)

Potter, C. S.; Brooks, V.

1997-01-01

This paper describes the use of satellite data to calibrate a new climate-vegetation greenness relationship for global change studies. We examined statistical relationships between annual climate indexes (temperature, precipitation, and surface radiation) and seasonal attributes If the AVHRR Normalized Difference Vegetation Index (NDVI) time series for the mid-1980's in order to refine our understanding of intra-annual patterns and global abiotic controls on natural vegetation dynamics. Multiple linear regression results using global 1o gridded data sets suggest that three climate indexes: degree days (growing/chilling), annual precipitation total, and an annual moisture index together can account to 70-80 percent of the geographic variation in the NDVI seasonal extremes (maximum and minimum values) for the calibration year 1984. Inclusion of the same annual climate index values from the previous year explains no substantial additional portion of the global scale variation in NDVI seasonal extremes. The monthly timing of NDVI extremes is closely associated with seasonal patterns in maximum and minimum temperature and rainfall, with lag times of 1 to 2 months. We separated well-drained areas from lo grid cells mapped as greater than 25 percent inundated coverage for estimation of both the magnitude and timing of seasonal NDVI maximum values. Predicted monthly NDVI, derived from our climate-based regression equations and Fourier smoothing algorithms, shows good agreement with observed NDVI for several different years at a series of ecosystem test locations from around the globe. Regions in which NDVI seasonal extremes are not accurately predicted are mainly high latitude zones, mixed and disturbed vegetation types, and other remote locations where climate station data are sparse.

[Value of early application of different doses of amino acids in parenteral nutrition among preterm infants].

PubMed

Liu, Zhi-Juan; Liu, Guo-Sheng; Chen, Yong-Ge; Zhang, Hui-Li; Wu, Xue-Fen

2015-01-01

To study the short-term response and tolerance of different doses of amino acids in parenteral nutrition among preterm infants. This study included 86 preterm infants who had a birth weight between 1 000 to 2 000 g and were admitted to the hospital within 24 hours of birth between March 2013 and June 2014. According to the early application of different doses of amino acids, they were randomized into low-dose group (n=29, 1.0 g/kg per day with an increase of 1.0 g/kg daily and a maximum of 3.5 g/kg per day), medium-dose group (n=28, 2.0 g/kg per day with an increase of 1.0 g/kg daily and a maximum of 3.7 g/kg per day), and high-dose group (n=29, 3.0 g/kg per day with an increase of 0.5-1.0 g/kg daily and a maximum of 4.0 g/kg per day). Other routine parenteral nutrition and enteral nutrition support were also applied. The maximum weight loss was lower and the growth rate of head circumference was greater in the high-dose group than in the low-dose group (P<0.05). The infants in the medium- and high-dose groups had faster recovery of birth weight, earlier attainment of 100 kcal/(kg·d) of enteral nutrition, shorter duration of hospital stay, and less hospital cost than those in the low-dose group (P<0.05). Blood urea nitrogen (BUN) levels in the high-dose group increased compared with the other two groups 7 days after birth (P<0.05). The levels of creatinine, pH, bicarbonate, bilirubin, and transaminase and the incidence of complications showed no significant differences between groups (P>0.05). Parenteral administration of high-dose amino acids in preterm infants within 24 hours after birth can improve the short-term nutritional status of preterm infants, but there is a transient increase in BUN level.

A Phase I Study of the Safety and Pharmacokinetics of Higher-Dose Icotinib in Patients With Advanced Non-Small Cell Lung Cancer

PubMed Central

Liu, Jian; Wu, Lihua; Wu, Guolan; Hu, Xingjiang; Zhou, Huili; Chen, Junchun; Zhu, Meixiang; Xu, Wei; Tan, Fenlai; Ding, Lieming; Wang, Yinxiang

2016-01-01

Lessons Learned This phase I study evaluated the maximum tolerated dose, dose-limiting toxicities, safety, pharmacokinetics, and efficacy of icotinib with a starting dose of 250 mg in pretreated, advanced non-small cell lung cancer patients. We observed a maximum tolerated dose of 500 mg with a favorable pharmacokinetics profile and antitumor activity. These findings provide clinicians with evidence for application of higher-dose icotinib. Background. Icotinib, an oral epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor, has shown favorable tolerability and antitumor activity at 100–200 mg in previous studies without reaching the maximum tolerated dose (MTD). In July 2011, icotinib was approved by the China Food and Drug Administration at a dose of 125 mg three times daily for the treatment of patients with locally advanced or metastatic non-small cell lung cancer (NSCLC) after failure of at least one platinum-based chemotherapy regimen. This study investigated the MTD, tolerability, and pharmacokinetics of higher-dose icotinib in patients with advanced NSCLC. Methods. Twenty-six patients with advanced NSCLC were treated at doses of 250–625 mg three times daily The EGFR mutation test was not mandatory in this study. Results. Twenty-four (92.3%) of 26 patients experienced at least one adverse event (AE); rash (61.5%), diarrhea (23.1%), and oral ulceration (11.5%) were most frequent AEs. Dose-limiting toxicities were seen in 2 of 6 patients in the 625-mg group, and the MTD was established at 500 mg. Icotinib was rapidly absorbed and eliminated. The amount of time that the drug was present at the maximum concentration in serum (Tmax) ranged from 1 to 3 hours (1.5–4 hours) after multiple doses. The t1/2 was similar after single- and multiple-dose administration (7.11 and 6.39 hours, respectively). A nonlinear relationship was observed between dose and drug exposure. Responses were seen in 6 (23.1%) patients, and 8 (30.8%) patients had stable disease. Conclusion. This study demonstrated that higher-dose icotinib was well-tolerated, with a MTD of 500 mg. Favorable antitumor activity and pharmacokinetic profile were observed in patients with heavily pretreated, advanced NSCLC. PMID:27789778

A Phase I Study of the Safety and Pharmacokinetics of Higher-Dose Icotinib in Patients With Advanced Non-Small Cell Lung Cancer.

PubMed

Liu, Jian; Wu, Lihua; Wu, Guolan; Hu, Xingjiang; Zhou, Huili; Chen, Junchun; Zhu, Meixiang; Xu, Wei; Tan, Fenlai; Ding, Lieming; Wang, Yinxiang; Shentu, Jianzhong

2016-11-01

This phase I study evaluated the maximum tolerated dose, dose-limiting toxicities, safety, pharmacokinetics, and efficacy of icotinib with a starting dose of 250 mg in pretreated, advanced non-small cell lung cancer patients. We observed a maximum tolerated dose of 500 mg with a favorable pharmacokinetics profile and antitumor activity.These findings provide clinicians with evidence for application of higher-dose icotinib. Icotinib, an oral epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor, has shown favorable tolerability and antitumor activity at 100-200 mg in previous studies without reaching the maximum tolerated dose (MTD). In July 2011, icotinib was approved by the China Food and Drug Administration at a dose of 125 mg three times daily for the treatment of patients with locally advanced or metastatic non-small cell lung cancer (NSCLC) after failure of at least one platinum-based chemotherapy regimen. This study investigated the MTD, tolerability, and pharmacokinetics of higher-dose icotinib in patients with advanced NSCLC. Twenty-six patients with advanced NSCLC were treated at doses of 250-625 mg three times daily The EGFR mutation test was not mandatory in this study. Twenty-four (92.3%) of 26 patients experienced at least one adverse event (AE); rash (61.5%), diarrhea (23.1%), and oral ulceration (11.5%) were most frequent AEs. Dose-limiting toxicities were seen in 2 of 6 patients in the 625-mg group, and the MTD was established at 500 mg. Icotinib was rapidly absorbed and eliminated. The amount of time that the drug was present at the maximum concentration in serum (T max ) ranged from 1 to 3 hours (1.5-4 hours) after multiple doses. The t 1/2 was similar after single- and multiple-dose administration (7.11 and 6.39 hours, respectively). A nonlinear relationship was observed between dose and drug exposure. Responses were seen in 6 (23.1%) patients, and 8 (30.8%) patients had stable disease. This study demonstrated that higher-dose icotinib was well-tolerated, with a MTD of 500 mg. Favorable antitumor activity and pharmacokinetic profile were observed in patients with heavily pretreated, advanced NSCLC. ©AlphaMed Press; the data published online to support this summary is the property of the authors.

Effective chemotherapy of heterogeneous and drug-resistant early colon cancers by intermittent dose schedules: a computer simulation study.

PubMed

Axelrod, David E; Vedula, Sudeepti; Obaniyi, James

2017-05-01

The effectiveness of cancer chemotherapy is limited by intra-tumor heterogeneity, the emergence of spontaneous and induced drug-resistant mutant subclones, and the maximum dose to which normal tissues can be exposed without adverse side effects. The goal of this project was to determine if intermittent schedules of the maximum dose that allows colon crypt maintenance could overcome these limitations, specifically by eliminating mixtures of drug-resistant mutants from heterogeneous early colon adenomas while maintaining colon crypt function. A computer model of cell dynamics in human colon crypts was calibrated with measurements of human biopsy specimens. The model allowed simulation of continuous and intermittent dose schedules of a cytotoxic chemotherapeutic drug, as well as the drug's effect on the elimination of mutant cells and the maintenance of crypt function. Colon crypts can tolerate a tenfold greater intermittent dose than constant dose. This allows elimination of a mixture of relatively drug-sensitive and drug-resistant mutant subclones from heterogeneous colon crypts. Mutants can be eliminated whether they arise spontaneously or are induced by the cytotoxic drug. An intermittent dose, at the maximum that allows colon crypt maintenance, can be effective in eliminating a heterogeneous mixture of mutant subclones before they fill the crypt and form an adenoma.

SU-E-T-365: Dosimetric Impact of Dental Amalgam CT Image Artifacts On IMRT and VMAT Head and Neck Plans

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cao, N; Young, L; Parvathaneni, U

Purpose: The presence of high density dental amalgam in patient CT image data sets causes dose calculation errors for head and neck (HN) treatment planning. This study assesses and compares dosimetric variations in IMRT and VMAT treatment plans due to dental artifacts. Methods: Sixteen HN patients with similar treatment sites (oropharynx), tumor volume and extensive dental artifacts were divided into two groups: IMRT (n=8, 6 to 9 beams) and VMAT (n=8, 2 arcs with 352° rotation). All cases were planned with the Pinnacle 9.2 treatment planning software using the collapsed cone convolution superposition algorithm and a range of prescription dosemore » from 60 to 72Gy. Two different treatment plans were produced, each based on one of two image sets: (a)uncorrected; (b)dental artifacts density overridden (set to 1.0g/cm{sup 3}). Differences between the two treatment plans for each of the IMRT and VMAT techniques were quantified by the following dosimetric parameters: maximum point dose, maximum spinal cord and brainstem dose, mean left and right parotid dose, and PTV coverage (V95%Rx). Average differences generated for these dosimetric parameters were compared between IMRT and VMAT plans. Results: The average absolute dose differences (plan a minus plan b) for the VMAT and IMRT techniques, respectively, caused by dental artifacts were: 2.2±3.3cGy vs. 37.6±57.5cGy (maximum point dose, P=0.15); 1.2±0.9cGy vs. 7.9±6.7cGy (maximum spinal cord dose, P=0.026); 2.2±2.4cGy vs. 12.1±13.0cGy (maximum brainstem dose, P=0.077); 0.9±1.1cGy vs. 4.1±3.5cGy (mean left parotid dose, P=0.038); 0.9±0.8cGy vs. 7.8±11.9cGy (mean right parotid dose, P=0.136); 0.021%±0.014% vs. 0.803%±1.44% (PTV coverage, P=0.17). Conclusion: For the HN plans studied, dental artifacts demonstrated a greater dose calculation error for IMRT plans compared to VMAT plans. Rotational arcs appear on the average to compensate dose calculation errors induced by dental artifacts. Thus, compared to VMAT, density overrides for dental artifacts are more important when planning IMRT of HN.« less

Dose Trends of Aripiprazole from 2004 to 2014 in Psychiatric Inpatients in Korea.

PubMed

Woo, Young Sup; Shim, In Hee; Lee, Sang-Yeol; Lee, Dae-Bo; Kim, Moon-Doo; Jung, Young-Eun; Lee, Jonghun; Won, Seunghee; Jon, Duk-In; Bahk, Won-Myong

2017-05-31

Although aripiprazole has been widely used to treat various psychiatric disorders, little is known about the adequate dosage for Asian patients in clinical practice. Hence, we evaluated the initial and maximum doses of aripiprazole from 2004 to 2014 to estimate the appropriate dosage for Korean psychiatric inpatients in clinical practice. In this retrospective study, we reviewed the medical records of patients who were hospitalized in five university hospitals in Korea from March 2004 to December 2014. The psychiatric diagnosis according to the text revision of the Diagnostic and Statistical Manual of Mental Disorders, 4th edition during index hospitalization and the initial and maximum doses of aripiprazole were evaluated. There were 74 patients in Wave 1 (2004-2006), 201 patients in Wave 2 (2007-2010), and 353 patients in Wave 3 (2011-2014). The initial doses of aripiprazole in all diagnostic groups were significantly lower in Wave 3 than in Wave 2. The maximum doses of aripiprazole in each diagnostic group were not significantly different among Waves 1, 2, and 3. The relatively low initial doses of aripiprazole documented in our study may reflect a strategy by clinicians to minimize the side effects associated with aripiprazole use, such as akathisia.

Regulatory Forum Opinion Piece*: Retrospective Evaluation of Doses in the 26-week Tg.rasH2 Mice Carcinogenicity Studies: Recommendation to Eliminate High Doses at Maximum Tolerated Dose in Future Studies. A Response to the Counterpoints.

PubMed

Paranjpe, Madhav G; Denton, Melissa D; Vidmar, Tom J; Elbekai, Reem H

2016-01-01

We recently conducted a retrospective analysis of data collected from 29 Tg.rasH2 carcinogenicity studies conducted at our facility to determine how successful was the strategy of choosing the high dose of the 26-week studies based on an estimated maximum tolerated dose (MTD). As a result of our publication, 2 counterviews were expressed. Both counterviews illustrate very valid points in their interpretation of our data. In this article, we would like to highlight clarifications based on several points and issues they have raised in their papers, namely, the dose-level selection, determining if MTD was exceeded in 26-week studies, and a discussion on the number of dose groups to be used in the studies. © The Author(s) 2015.

Evaluation of radiological impacts of tenorm in the Tunisian petroleum industry.

PubMed

Hrichi, Hajer; Baccouche, Souad; Belgaied, Jamel-Eddine

2013-01-01

The health impacts associated with uncontrolled release of TENORM in products and wastes released in the petroleum industry are of great concern. In this study, evaluation of TENORM in the Tunisian petroleum products and wastes is presented. Fourteen products samples, twelve waste samples and three samples from the surrounding environment were collected from the Tunisian Refinery STIR site and from two onshore production oilfields. The activity concentrations of (232)Th, (226)Ra and (40)K for all samples were determined using gamma-ray spectrometry with High Purity Germanium (HPGe) detector. The activity concentrations of (224)Ra were calculated only for scale samples. The radium equivalent activity, external and internal hazard indices, absorbed doses rates in air and annual effective dose were also estimated. It was noticed that maximum value of Ra(eq) activity was found to be 398 Bq/kg in scale (w8) collected from an onshore production oilfield which exceeds the maximum Ra(eq) value of 370 Bq/kg recommended for safe use. All hazard indices indicated that scale samples (w6, w7, w8 and w11) could be a significant waste problem especially sample (w8). In this study, the radium isotopic data were used to provide an estimate of scale samples ages by the use of the (224)Ra/(228)Ra activity ratio dating method. Ages of collected scales were found to be in the range 0.91-2.4 years. In this work, radioactivity (NORM contamination) in samples collected from the refinery STIR are showed to be insignificant if compared to those from onshore oilfield production sites. Copyright © 2012 Elsevier Ltd. All rights reserved.

210Po in the diet at Seville (Spain) and its contribution to the dose by ingestion

PubMed Central

Díaz-Francés, I.; Mantero, J.; Díaz-Ruiz, J.; Manjón, G.; García-Tenorio, R.

2016-01-01

The activity concentrations of 210Po have been determined in a total of 24 representative diet samples from Seville (south of Spain), inferring from the obtained values the annual intakes of 210Po by ingestion of the affected population and the corresponding committed effective doses. The annual intakes of 210Po and, consequently, the corresponding doses of this radionuclide show a high variability in correspondence with the variability in the composition of the analysed samples over time, and their magnitude is comparable with the estimated ones in other regions/countries of the world with similar diet habits (countries where the marine products have a considerable weight in the diets). Committed effective doses by ingestion higher than 0.1 mSv y−1 have been estimated exclusively for 210Po, reflecting the importance of this radionuclide and this route of incorporation in the magnitude of the total doses received by the affected population from natural sources. PMID:25802464

The Annual Cycle of Water Vapor on Mars as Observed by the Thermal Emission Spectrometer

NASA Technical Reports Server (NTRS)

Smith, Michael D.; Vondrak, Richard R. (Technical Monitor)

2001-01-01

Spectra taken by the Mars Global Surveyor Thermal Emission Spectrometer (TES) have been used to monitor the latitude, longitude, and seasonal dependence of water vapor for over one full Martian year (March 1999-March 2001). A maximum in water vapor abundance is observed at high latitudes during mid-summer in both hemispheres, reaching a maximum value of approximately 100 pr-micrometer in the north and approximately 50 pr-micrometer in the south. Low water vapor abundance (<5 pr-micrometer) is observed at middle and high latitudes in the fall and winter of both hemispheres. There are large differences in the hemispheric (north versus south) and seasonal (perihelion versus aphelion) behavior of water vapor. The latitudinal and seasonal dependence of the decay of the northern summer water vapor maximum implies cross-equatorial transport of water to the southern hemisphere, while there is little or no corresponding transport during the decay of the southern hemisphere summer maximum. The latitude-longitude dependence of annually-averaged water vapor (corrected for topography) has a significant positive correlation with albedo and significant negative correlations with thermal inertia and surface pressure. Comparison of TES results with those retrieved from the Viking Orbiter Mars Atmospheric Water Detectors (MAWD) experiments shows some similar features, but also many significant differences. The southern hemisphere maximum observed by TES was not observed by MAWD and the large latitudinal gradient in annually-averaged water vapor observed by MAWD does not appear in the TES results.

Radiation Doses to Hanford Workers from Natural Potassium-40

DOE Office of Scientific and Technical Information (OSTI.GOV)

Strom, Daniel J.; Lynch, Timothy P.; Weier, Dennis R.

2009-02-01

The chemical element potassium is an essential mineral in people and is subject to homeostatic regulation. Natural potassium comprises three isotopes, 39K, 40K, and 41K. Potassium-40 is radioactive, with a half life of 1.248 billion years. In most transitions, it emits a β particle with a maximum energy of 0.560 MeV, and sometimes a gamma photon of 1.461 MeV. Because it is ubiquitous, 40K produces radiation dose to all human beings. This report contains the results of new measurements of 40K in 248 adult females and 2,037 adult males performed at the Department of Energy Hanford Site in 2006 andmore » 2007. Potassium concentrations diminish with age, are generally lower in women than in men, and decrease with body mass index (BMI). The average annual effective dose from 40K in the body is 0.149 mSv y -1 for men and 0.123 mSv y -1 women respectively. Averaged over both men and women, the average effective dose per year is 0.136 mSv y -1. Calculated effective doses range from 0.069 to 0.243 mSv y -1 for adult males, and 0.067 to 0.203 mSv y -1 for adult females, a roughly three-fold variation for each gender. The need for dosimetric phantoms with a greater variety of BMI values should be investigated. From our data, it cannot be determined whether the potassium concentration in muscle in people with large BMI values differs from that in people with small BMI values. Similarly, it would be important to know the potassium concentration in other soft tissues, since much of the radiation dose is due to beta radiation, in which the source and target tissues are the same. These uncertainties should be evaluated to determine their consequences for dosimetry.« less

SU-E-T-169: Characterization of Pacemaker/ICD Dose in SAVI HDR Brachytherapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kalavagunta, C; Lasio, G; Yi, B

2015-06-15

Purpose: It is important to estimate dose to pacemaker (PM)/Implantable Cardioverter Defibrillator (ICD) before undertaking Accelerated Partial Breast Treatment using High Dose Rate (HDR) brachytherapy. Kim et al. have reported HDR PM/ICD dose using a single-source balloon applicator. To the authors knowledge, there have so far not been any published PM/ICD dosimetry literature for the Strut Adjusted Volume Implant (SAVI, Cianna Medical, Aliso Viejo, CA). This study aims to fill this gap by generating a dose look up table (LUT) to predict maximum dose to the PM/ICD in SAVI HDR brachytherapy. Methods: CT scans for 3D dosimetric planning were acquiredmore » for four SAVI applicators (6−1-mini, 6−1, 8−1 and 10−1) expanded to their maximum diameter in air. The CT datasets were imported into the Elekta Oncentra TPS for planning and each applicator was digitized in a multiplanar reconstruction window. A dose of 340 cGy was prescribed to the surface of a 1 cm expansion of the SAVI applicator cavity. Cartesian coordinates of the digitized applicator were determined in the treatment leading to the generation of a dose distribution and corresponding distance-dose prediction look up table (LUT) for distances from 2 to 15 cm (6-mini) and 2 to 20 cm (10–1).The deviation between the LUT doses and the dose to the cardiac device in a clinical case was evaluated. Results: Distance-dose look up table were compared to clinical SAVI plan and the discrepancy between the max dose predicted by the LUT and the clinical plan was found to be in the range (−0.44%, 0.74%) of the prescription dose. Conclusion: The distance-dose look up tables for SAVI applicators can be used to estimate the maximum dose to the ICD/PM, with a potential usefulness for quick assessment of dose to the cardiac device prior to applicator placement.« less

Hydrothermal extremes at the South-West Pribaikalie during the current climate changes

NASA Astrophysics Data System (ADS)

Voropay, Nadezhda

2017-04-01

Climatic extremes of air temperature and precipitation were analyzed for the Tunka Intermountain Depression (South-West Pribaikalie, Buryatia, Russian Federation). Intermountain depressions occupy a quarter of the territory of the Baikal region. The specific climatic conditions in the depressions are formed due to the geographic location and the influence of latitudinal zonation and altitudinal gradients. Air temperature and precipitation data records from at weather stations for the period 1940-2015 were analyzed. Long-term average annual temperature is negative and varies from -0.8 °C to -2.4 °C. Air temperature absolute minimum is -48 °C, absolute maximum is +36 °C. The long-term average annual precipitation is 370-480 mm, but in some years annual precipitation reach 760 mm. The summer months have about 70% of the total annual precipitation, in July and August the sum may reach 340 mm. Maximum daily sum of rainfalls is 80 mm. The contribution of the global and regional circulation characteristics into the variability of regional climatic characteristics was estimated.

21 CFR 361.1 - Radioactive drugs for certain research uses.

Code of Federal Regulations, 2014 CFR

2014-04-01

... following: Whole body, active blood-forming organs, lens of the eye, and gonads: Rems Single dose 3 Annual... body, active blood-forming organs, lens of the eye, gonads, and other organ doses from the administered... set forth in paragraph (d) of this section, that: (i) The pharmacological dose is within the limits...

21 CFR 361.1 - Radioactive drugs for certain research uses.

Code of Federal Regulations, 2013 CFR

2013-04-01

... following: Whole body, active blood-forming organs, lens of the eye, and gonads: Rems Single dose 3 Annual... body, active blood-forming organs, lens of the eye, gonads, and other organ doses from the administered... set forth in paragraph (d) of this section, that: (i) The pharmacological dose is within the limits...

21 CFR 361.1 - Radioactive drugs for certain research uses.

Code of Federal Regulations, 2012 CFR

2012-04-01

... following: Whole body, active blood-forming organs, lens of the eye, and gonads: Rems Single dose 3 Annual... body, active blood-forming organs, lens of the eye, gonads, and other organ doses from the administered... set forth in paragraph (d) of this section, that: (i) The pharmacological dose is within the limits...

A Phase II Trial on the Effect of Low-Dose versus High-Dose Vitamin D Supplementation on Bone Mass in Adults with Neurofibromatosis 1 (NF1)

DTIC Science & Technology

2013-10-01

MD, PhD CONTRACTING ORGANIZATION: University of Utah REPORT DATE : October 2013 TYPE OF REPORT: Annual PREPARED FOR: U.S...of information if it does not display a currently valid OMB control number. PLEASE DO NOT RETURN YOUR FORM TO THE ABOVE ADDRESS. 1. REPORT DATE ...October 2013 2. REPORT TYPE Annual 3. DATES COVERED 15 September 2012-14 September 2013 4. TITLE AND SUBTITLE A Phase II Trial on the Effect of

Monte Carlo and Phantom Study of the Radiation Dose to the Body from Dedicated Computed Tomography of the Breast

PubMed Central

Sechopoulos, Ioannis; Vedantham, Srinivasan; Suryanarayanan, Sankararaman; D’Orsi, Carl J.; Karellas, Andrew

2008-01-01

Purpose To prospectively determine the radiation dose absorbed by the organs and tissues of the body during a dedicated computed tomography of the breast (DBCT) study using Monte Carlo methods and a phantom. Materials and Methods Using the Geant4 Monte Carlo toolkit, the Cristy anthropomorphic phantom and the geometry of a prototype DBCT was simulated. The simulation was used to track x-rays emitted from the source until their complete absorption or exit from the simulation limits. The interactions of the x-rays with the 65 different volumes representing organs, bones and other tissues of the anthropomorphic phantom that resulted in energy deposition were recorded. These data were used to compute the radiation dose to the organs and tissues during a complete DBCT acquisition relative to the average glandular dose to the imaged breast (ROD, relative organ dose), using the x-ray spectra proposed for DBCT imaging. The effectiveness of a lead shield for reducing the dose to the organs was investigated. Results The maximum ROD among the organs was for the ipsilateral lung with a maximum of 3.25%, followed by the heart and the thymus. Of the skeletal tissues, the sternum received the highest dose with a maximum ROD to the bone marrow of 2.24%, and to the bone surface of 7.74%. The maximum ROD to the uterus, representative of that of an early-stage fetus, was 0.026%. These maxima occurred for the highest energy x-ray spectrum (80 kVp) analyzed. A lead shield does not protect substantially the organs that receive the highest dose from DBCT. Discussion Although the dose to the organs from DBCT is substantially higher than that from planar mammography, they are comparable or considerably lower than those reached by other radiographic procedures and much lower than other CT examinations. PMID:18292479

Impact of cardiosynchronous brain pulsations on Monte Carlo calculated doses for synchrotron micro- and minibeam radiation therapy.

PubMed

Manchado de Sola, Francisco; Vilches, Manuel; Prezado, Yolanda; Lallena, Antonio M

2018-05-15

The purpose of this study was to assess the effects of brain movements induced by heartbeat on dose distributions in synchrotron micro- and minibeam radiation therapy and to develop a model to help guide decisions and planning for future clinical trials. The Monte Carlo code PENELOPE was used to simulate the irradiation of a human head phantom with a variety of micro- and minibeam arrays, with beams narrower than 100 μm and above 500 μm, respectively, and with radiation fields of 1 × 2 cm and 2 × 2 cm. The dose in the phantom due to these beams was calculated by superposing the dose profiles obtained for a single beam of 1 μm × 2 cm. A parameter δ, accounting for the total displacement of the brain during the irradiation and due to the cardiosynchronous pulsation, was used to quantify the impact on peak-to-valley dose ratios and the full width at half maximum. The difference between the maximum (at the phantom entrance) and the minimum (at the phantom exit) values of the peak-to-valley dose ratio reduces when the parameter δ increases. The full width at half maximum remains almost constant with depth for any δ value. Sudden changes in the two quantities are observed at the interfaces between the various tissues (brain, skull, and skin) present in the head phantom. The peak-to-valley dose ratio at the center of the head phantom reduces when δ increases, remaining above 70% of the static value only for minibeams and δ smaller than ∼200 μm. Optimal setups for brain treatments with synchrotron radiation micro- and minibeam combs depend on the brain displacement due to cardiosynchronous pulsation. Peak-to-valley dose ratios larger than 90% of the maximum values obtained in the static case occur only for minibeams and relatively large dose rates. © 2018 American Association of Physicists in Medicine.

Evaluation of indoor radon equilibrium factor using CFD modeling and resulting annual effective dose

NASA Astrophysics Data System (ADS)

Rabi, R.; Oufni, L.

2018-04-01

The equilibrium factor is an important parameter for reasonably estimating the population dose from radon. However, the equilibrium factor value depended mainly on the ventilation rate and the meteorological factors. Therefore, this study focuses on investigating numerically the influence of the ventilation rate, temperature and humidity on equilibrium factor between radon and its progeny. The numerical results showed that ventilation rate, temperature and humidity have significant impacts on indoor equilibrium factor. The variations of equilibrium factor with the ventilation, temperature and relative humidity are discussed. Moreover, the committed equivalent doses due to 218Po and 214Po radon short-lived progeny were evaluated in different tissues of the respiratory tract of the members of the public from the inhalation of indoor air. The annual effective dose due to radon short lived progeny from the inhalation of indoor air by the members of the public was investigated.

Measurements of long-term external and internal radiation exposure of inhabitants of some villages of the Bryansk region of Russia after the Chernobyl accident.

PubMed

Bernhardsson, C; Zvonova, I; Rääf, C; Mattsson, S

2011-10-15

A Nordic-Soviet programme was initiated in 1990 to evaluate the external and internal radiation exposure of the inhabitants of several villages in the Bryansk region of Russia. This area was one of the number of areas particularly affected by the nuclear accident at the Chernobyl Nuclear Power Plant in 1986. Measurements were carried out yearly until 1998 and after that more irregularly; in 2000, 2006 and 2008 respectively. The effective dose estimates were based on individual thermoluminescent dosemeters and on in vivo measurements of the whole body content of (137)Cs (and (134)Cs during the first years of the programme). The decrease in total effective dose during the almost 2 decade follow-up was due to a continuous decrease in the dominating external exposure and a less decreasing but highly variable exposure from internal irradiation. In 2008, the observed average effective dose (i.e. the sum of external and internal exposure) from Chernobyl (137)Cs to the residents was estimated to be 0.3mSv y(-1). This corresponds to 8% of the estimated annual dose in 1990 and to 1% of the estimated annual dose in 1986. As a mean for the population group and for the period of the present study (2006-2008), the average yearly effective dose from Chernobyl cesium was comparable to the absorbed dose obtained annually from external exposure to cosmic radiation plus internal exposure to naturally occurring radionuclides in the human body. Our data indicate that the effective dose from internal exposure is becoming increasingly important as the body burdens of Chernobyl (137)Cs are decreasing more slowly than the external exposure. However, over the years there have been large individual variations in both the external and internal effective doses, as well as differences between the villages investigated. These variations and differences are presented and discussed in this paper. Copyright © 2011 Elsevier B.V. All rights reserved.

Use of iodine for water disinfection: iodine toxicity and maximum recommended dose.

PubMed Central

Backer, H; Hollowell, J

2000-01-01

Iodine is an effective, simple, and cost-efficient means of water disinfection for people who vacation, travel, or work in areas where municipal water treatment is not reliable. However, there is considerable controversy about the maximum safe iodine dose and duration of use when iodine is ingested in excess of the recommended daily dietary amount. The major health effect of concern with excess iodine ingestion is thyroid disorders, primarily hypothyroidism with or without iodine-induced goiter. A review of the human trials on the safety of iodine ingestion indicates that neither the maximum recommended dietary dose (2 mg/day) nor the maximum recommended duration of use (3 weeks) has a firm basis. Rather than a clear threshold response level or a linear and temporal dose-response relationship between iodine intake and thyroid function, there appears to be marked individual sensitivity, often resulting from unmasking of underlying thyroid disease. The use of iodine for water disinfection requires a risk-benefit decision based on iodine's benefit as a disinfectant and the changes it induces in thyroid physiology. By using appropriate disinfection techniques and monitoring thyroid function, most people can use iodine for water treatment over a prolonged period of time. PMID:10964787

Summary of annual mean, maximum, minimum, and L-scale statistics of daily mean streamflow for 712 U.S. Geological Survey streamflow-gaging Stations in Texas Through 2003

USGS Publications Warehouse

Asquith, William H.; Vrabel, Joseph; Roussel, Meghan C.

2007-01-01

Analysts and managers of surface-water resources might have interest in selected statistics of daily mean streamflow for U.S. Geological Survey (USGS) streamflow-gaging stations in Texas. The selected statistics are the annual mean, maximum, minimum, and L-scale of daily meanstreamflow. Annual L-scale of streamflow is a robust measure of the variability of the daily mean streamflow for a given year. The USGS, in cooperation with the Texas Commission on Environmental Quality, initiated in 2006a data and reporting process to generate annual statistics for 712 USGS streamflow-gaging stations in Texas. A graphical depiction of the history of the annual statistics for most active and inactive, continuous-record gaging stations in Texas provides valuable information by conveying the historical perspective of streamflow for the watershed. Each figure consists off our time-series plots of the annual statistics of daily mean streamflow for each streamflow-gaging station. Each of the four plots is augmented with horizontal lines that depict the mean and median annual values of the corresponding statistic for the period of record. Monotonic trends for each of the four annual statistics also are identified using Kendall's T. The history of one or more streamflow-gaging stations could be used in a watershed, river basin, or other regional context by analysts and managers of surface-water resources to guide scientific, regulatory, or other inquiries of streamflow conditions in Texas.

The radioactivity estimation of 14C and 3H in graphite waste samples of the KRR-2.

PubMed

Reyoung Kim, Hee

2013-09-01

The radioactivity of (14)C and (3)H in graphite samples from the dismantled Korea Research Reactor-2 (the KRR-2) site was analyzed by high-temperature oxidation and liquid scintillation counting, and the graphite waste was suggested to be disposed of as a low-level radioactive waste. The graphite samples were oxidized at a high temperature of 800 °C, and their counting rates were measured by using a liquid scintillation counter (LSC). The combustion ratio of the graphite was about 99% on the sample with a maximum weight of 1g. The recoveries from the combustion furnace were around 100% and 90% in (14)C and (3)H, respectively. The minimum detectable activity was 0.04-0.05 Bq/g for the (14)C and 0.13-0.15 Bq/g for the (3)H at the same background counting time. The activity of (14)C was higher than that of (3)H over all samples with the activity ratios of the (14)C to (3)H, (14)C/(3)H, being between 2.8 and 25. The dose calculation was carried out from its radioactivity analysis results. The dose estimation gave a higher annual dose than the domestic legal limit for a clearance. It was thought that the sampled graphite waste from the dismantled research reactor was not available for reuse or recycling and should be monitored as low-level radioactive waste. Copyright © 2013 Elsevier Ltd. All rights reserved.

Management of neonatal abstinence syndrome: a national survey and review of practice.

PubMed

O'Grady, M J; Hopewell, J; White, M J

2009-07-01

To ascertain the present management of neonatal abstinence syndrome (NAS) in neonatal units in the United Kingdom (UK) and Ireland. Postal questionnaire to 235 neonatal units, with telephone follow-up of non-respondents. The response rate was 90%, and 96% of respondents had a formal NAS guideline. The median number of infants treated annually for NAS was 6 (range 1-100). The method of Finnegan was the most widely used scoring system (52%). Morphine sulphate was the most commonly used first line agent for both opiate (92%) and polysubstance (69%) withdrawal. Dosing regimens varied widely. Units using a maximum daily morphine dose of <400 microg/kg/day were more likely to require the addition of a second agent (76% vs 58%, p = 0.027). Phenobarbitone was the drug of choice to treat seizures secondary to both opiate and polydrug withdrawal in 73% and 81% of units, respectively. 29% of units allowed infants to be discharged home on medication. 58% of these allowed administration of opiates in the community and in almost half of cases this was managed by a parent. Mothers on methadone whose serology was positive for hepatitis B and/or C were four times more likely to be discouraged from breastfeeding. The majority of units currently use an opiate as the drug of first choice as recommended. Doses utilised and second agents added vary significantly between units. Many of our findings reflect the lack of high-quality randomised studies regarding management of NAS.

Is it possible to avoid hypopituitarism after irradiation of pituitary adenomas by the Leksell gamma knife?

PubMed

Marek, Josef; Jezková, Jana; Hána, Václav; Krsek, Michal; Bandúrová, L'ubomíra; Pecen, Ladislav; Vladyka, Vilibald; Liscák, Roman

2011-02-01

Radiation therapy is one of the treatment options for pituitary adenomas. The most common side effect associated with Leksell gamma knife (LGK) irradiation is the development of hypopituitarism. The aim of this study was to verify that hypopituitarism does not develop if the maximum mean dose to pituitary is kept under 15 Gy and to evaluate the influence of maximum distal infundibulum dose on the development of hypopituitarism. We followed the incidence of hypopituitarism in 85 patients irradiated with LGK in 1993-2003. The patients were divided in two subgroups: the first subgroup followed prospectively (45 patients), irradiated with a mean dose to pituitary <15 Gy; the second subgroup followed retrospectively 1993-2001 and prospectively 2001-2009 (40 patients), irradiated with a mean dose to pituitary >15 Gy. Serum TSH, free thyroxine, testosterone or 17β-oestradiol, IGF1, prolactin and cortisol levels were evaluated before and every 6 months after LGK irradiation. Hypopituitarism after LGK irradiation developed only in 1 out of 45 (2.2%) patients irradiated with a mean dose to pituitary <15 Gy, in contrast to 72.5% patients irradiated with a mean dose to pituitary >15 Gy. The radiation dose to the distal infundibulum was found as an independent factor of hypopituitarism with calculated maximum safe dose of 17 Gy. Keeping the mean radiation dose to pituitary under 15 Gy and the dose to the distal infundibulum under 17 Gy prevents the development of hypopituitarism following LGK irradiation.

DOSIMETRIC CONSEQUENCES OF USING CONTRAST-ENHANCED COMPUTED TOMOGRAPHIC IMAGES FOR INTENSITY-MODULATED STEREOTACTIC BODY RADIOTHERAPY PLANNING.

PubMed

Yoshikawa, Hiroto; Roback, Donald M; Larue, Susan M; Nolan, Michael W

2015-01-01

Potential benefits of planning radiation therapy on a contrast-enhanced computed tomography scan (ceCT) should be weighed against the possibility that this practice may be associated with an inadvertent risk of overdosing nearby normal tissues. This study investigated the influence of ceCT on intensity-modulated stereotactic body radiotherapy (IM-SBRT) planning. Dogs with head and neck, pelvic, or appendicular tumors were included in this retrospective cross-sectional study. All IM-SBRT plans were constructed on a pre- or ceCT. Contours for tumor and organs at risk (OAR) were manually constructed and copied onto both CT's; IM-SBRT plans were calculated on each CT in a manner that resulted in equal radiation fluence. The maximum and mean doses for OAR, and minimum, maximum, and mean doses for targets were compared. Data were collected from 40 dogs per anatomic site (head and neck, pelvis, and limbs). The average dose difference between minimum, maximum, and mean doses as calculated on pre- and ceCT plans for the gross tumor volume was less than 1% for all anatomic sites. Similarly, the differences between mean and maximum doses for OAR were less than 1%. The difference in dose distribution between plans made on CTs with and without contrast enhancement was tolerable at all treatment sites. Therefore, although caution would be recommended when planning IM-SBRT for tumors near "reservoirs" for contrast media (such as the heart and urinary bladder), findings supported the use of ceCT with this dose calculation algorithm for both target delineation and IM-SBRT treatment planning. © 2015 American College of Veterinary Radiology.

Occupational radiation dose to eyes from interventional radiology procedures in light of the new eye lens dose limit from the International Commission on Radiological Protection

PubMed Central

Walsh, C; Gallagher, A; Dowling, A; Guiney, M; Ryan, J M; McEniff, N; O'Reilly, G

2015-01-01

Objective: In 2011, the International Commission on Radiological Protection (ICRP) recommended a substantial reduction in the equivalent dose limit for the lens of the eye, in line with a reduced threshold of absorbed dose for radiation-induced cataracts. This is of particular relevance in interventional radiology (IR) where it is well established that staff doses can be significant, however, there is a lack of data on IR eye doses in terms of Hp(3). Hp(3) is the personal dose equivalent at a depth of 3 mm in soft tissue and is used for measuring lens dose. We aimed to obtain a reliable estimate of eye dose to IR operators. Methods: Lens doses were measured for four interventional radiologists over a 3-month period using dosemeters specifically designed to measure Hp(3). Results: Based on their typical workloads, two of the four interventional radiologists would exceed the new ICRP dose limit with annual estimated doses of 31 and 45 mSv to their left eye. These results are for an “unprotected” eye, and for IR staff who routinely wear lead glasses, the dose beneath the glasses is likely to be significantly lower. Staff eye dose normalized to patient kerma–area product and eye dose per procedure have been included in the analysis. Conclusion: Eye doses to IR operators have been established using a dedicated Hp(3) dosemeter. Estimated annual doses have the potential to exceed the new ICRP limit. Advances in knowledge: We have estimated lens dose to interventional radiologists in terms of Hp(3) for the first time in an Irish hospital setting. PMID:25761211

Assessing the possible radiological impact of routine radiological discharges from proposed nuclear power stations in England and Wales.

PubMed

Jones, Alison; Jones, Kelly; Holmes, Sheila; Ewers, Leon; Cabianca, Tiberio

2013-03-01

The aim of this work is to assess the possible radiological impact on the population of the United Kingdom (UK) from new nuclear power stations proposed for up to eight sites in England and Wales. The radiological impact was measured in terms of collective dose to the UK, European and world populations from a single year's discharge integrated to 500 and 100 000 years and the annual dose to an average member of the UK population (known as the per-caput dose). The doses were calculated for two reactor types, UK EPR™ and AP1000™, using the annual expected discharges estimated by the designers of the reactors and assuming two reactors per site. In addition, typical individual doses to adults living close to the sites were calculated on the basis of continuous discharges for 60 years (the assumed lifetime of the reactors). The dose to a representative person (previously known as the critical group) was not calculated, as this has been done elsewhere. The assessments were carried out using the software program PC-CREAM 08(®) which implements the updated European Commission methodology for assessing the radiological impact of routine releases of radionuclides to the environment. The collective dose truncated to 500 years to the UK population was estimated to be 0.5 manSv assuming UK EPR reactors on all sites and 0.6 manSv assuming AP1000s on three sites with UK EPRs on the other sites. The most significant contribution to the collective dose to the UK population is due to the global circulation of carbon-14 released to the atmosphere. The annual dose to an average member of the UK population from all sites was calculated to be around 10 nSv y(-1) and would therefore contribute little to an individual's total radiation dose. All the calculated doses to a typical adult living near the sites assuming continuous discharges for 60 years were found to be below 1 μSv y(-1).

Estimation of peak discharge quantiles for selected annual exceedance probabilities in northeastern Illinois

USGS Publications Warehouse

Over, Thomas M.; Saito, Riki J.; Veilleux, Andrea G.; Sharpe, Jennifer B.; Soong, David T.; Ishii, Audrey L.

2016-06-28

This report provides two sets of equations for estimating peak discharge quantiles at annual exceedance probabilities (AEPs) of 0.50, 0.20, 0.10, 0.04, 0.02, 0.01, 0.005, and 0.002 (recurrence intervals of 2, 5, 10, 25, 50, 100, 200, and 500 years, respectively) for watersheds in Illinois based on annual maximum peak discharge data from 117 watersheds in and near northeastern Illinois. One set of equations was developed through a temporal analysis with a two-step least squares-quantile regression technique that measures the average effect of changes in the urbanization of the watersheds used in the study. The resulting equations can be used to adjust rural peak discharge quantiles for the effect of urbanization, and in this study the equations also were used to adjust the annual maximum peak discharges from the study watersheds to 2010 urbanization conditions.The other set of equations was developed by a spatial analysis. This analysis used generalized least-squares regression to fit the peak discharge quantiles computed from the urbanization-adjusted annual maximum peak discharges from the study watersheds to drainage-basin characteristics. The peak discharge quantiles were computed by using the Expected Moments Algorithm following the removal of potentially influential low floods defined by a multiple Grubbs-Beck test. To improve the quantile estimates, regional skew coefficients were obtained from a newly developed regional skew model in which the skew increases with the urbanized land use fraction. The drainage-basin characteristics used as explanatory variables in the spatial analysis include drainage area, the fraction of developed land, the fraction of land with poorly drained soils or likely water, and the basin slope estimated as the ratio of the basin relief to basin perimeter.This report also provides the following: (1) examples to illustrate the use of the spatial and urbanization-adjustment equations for estimating peak discharge quantiles at ungaged sites and to improve flood-quantile estimates at and near a gaged site; (2) the urbanization-adjusted annual maximum peak discharges and peak discharge quantile estimates at streamgages from 181 watersheds including the 117 study watersheds and 64 additional watersheds in the study region that were originally considered for use in the study but later deemed to be redundant.The urbanization-adjustment equations, spatial regression equations, and peak discharge quantile estimates developed in this study will be made available in the web application StreamStats, which provides automated regression-equation solutions for user-selected stream locations. Figures and tables comparing the observed and urbanization-adjusted annual maximum peak discharge records by streamgage are provided at https://doi.org/10.3133/sir20165050 for download.

40 CFR Appendix A to Part 197 - Calculation of Annual Committed Effective Dose Equivalent

Code of Federal Regulations, 2011 CFR

2011-07-01

... resulting from irradiation of the tissue or organ to the total risk when the whole body is irradiated... internal irradiation from incorporated radionuclides, the total absorbed dose will be spread out in time...

40 CFR Appendix A to Part 197 - Calculation of Annual Committed Effective Dose Equivalent

Code of Federal Regulations, 2012 CFR

2012-07-01

... resulting from irradiation of the tissue or organ to the total risk when the whole body is irradiated... internal irradiation from incorporated radionuclides, the total absorbed dose will be spread out in time...

40 CFR Appendix A to Part 197 - Calculation of Annual Committed Effective Dose Equivalent

Code of Federal Regulations, 2014 CFR

2014-07-01

... resulting from irradiation of the tissue or organ to the total risk when the whole body is irradiated... internal irradiation from incorporated radionuclides, the total absorbed dose will be spread out in time...

40 CFR Appendix A to Part 197 - Calculation of Annual Committed Effective Dose Equivalent

Code of Federal Regulations, 2013 CFR

2013-07-01

... resulting from irradiation of the tissue or organ to the total risk when the whole body is irradiated... internal irradiation from incorporated radionuclides, the total absorbed dose will be spread out in time...

40 CFR Appendix A to Part 197 - Calculation of Annual Committed Effective Dose Equivalent

Code of Federal Regulations, 2010 CFR

2010-07-01

... resulting from irradiation of the tissue or organ to the total risk when the whole body is irradiated... internal irradiation from incorporated radionuclides, the total absorbed dose will be spread out in time...

Spatial-temporal changes of maximum and minimum temperatures in the Wei River Basin, China: Changing patterns, causes and implications

NASA Astrophysics Data System (ADS)

Liu, Saiyan; Huang, Shengzhi; Xie, Yangyang; Huang, Qiang; Leng, Guoyong; Hou, Beibei; Zhang, Ying; Wei, Xiu

2018-05-01

Due to the important role of temperature in the global climate system and energy cycles, it is important to investigate the spatial-temporal change patterns, causes and implications of annual maximum (Tmax) and minimum (Tmin) temperatures. In this study, the Cloud model were adopted to fully and accurately analyze the changing patterns of annual Tmax and Tmin from 1958 to 2008 by quantifying their mean, uniformity, and stability in the Wei River Basin (WRB), a typical arid and semi-arid region in China. Additionally, the cross wavelet analysis was applied to explore the correlations among annual Tmax and Tmin and the yearly sunspots number, Arctic Oscillation, Pacific Decadal Oscillation, and soil moisture with an aim to determine possible causes of annual Tmax and Tmin variations. Furthermore, temperature-related impacts on vegetation cover and precipitation extremes were also examined. Results indicated that: (1) the WRB is characterized by increasing trends in annual Tmax and Tmin, with a more evident increasing trend in annual Tmin, which has a higher dispersion degree and is less uniform and stable than annual Tmax; (2) the asymmetric variations of Tmax and Tmin can be generally explained by the stronger effects of solar activity (primarily), large-scale atmospheric circulation patterns, and soil moisture on annual Tmin than on annual Tmax; and (3) increasing annual Tmax and Tmin have exerted strong influences on local precipitation extremes, in terms of their duration, intensity, and frequency in the WRB. This study presents new analyses of Tmax and Tmin in the WRB, and the findings may help guide regional agricultural production and water resources management.

A study on natural radioactivity in Khewra Salt Mines, Pakistan.

PubMed

Baloch, Muzahir Ali; Qureshi, Aziz Ahmed; Waheed, Abdul; Ali, Muhammad; Ali, Nawab; Tufail, Muhammad; Batool, Saima; Akram, Muhammad; Iftikhar, Poonam; Qayyum, Hamza; Manzoor, Shahid; Khan, Hameed Ahmed

2012-01-01

The Khewra Salt Mines, the second largest salt mines in the world, are located 160 km south of Islamabad, the capital of Pakistan. Around 1000 workers are involved in the removal of salt from these mines. More than 40,000 visitors come annually to see the mines. The visitors and workers are directly exposed to the internal and external radiological hazards of radon and gamma rays in these mines. The general public is affected by the intake of the salt containing the naturally occurring radionuclides. Therefore the concentration of radon (²²²Rn) in the Khewra Salt Mines and activity concentrations of the naturally occurring radionuclides in the salt samples from these mines were measured. Both active and passive techniques were employed for the measurement of radon with Radon Alpha Detector (RAD-7) and SSNTD respectively. The concentration of ²²²Rn was 26 ± 4 Bq m⁻³ measured by the active method while 43 ± 8 Bq m⁻³ was measured by the passive method. The activity concentration of the radionuclides was measured using gamma ray spectrometry with HPGe detector. The mean activity of ⁴⁰K in salt samples was found to be 36 ± 20 Bq kg⁻¹ and the concentration of ²²⁶Ra and ²³²Th in the salt samples was below the detection limits. Gamma radiation hazard was assessed in terms of the external gamma dose from salt slabs and the rooms made of salt and the annual effective dose due to gamma radiation. The exposure to radon daughters, annual effective dose and excessive lifetime cancer risk due to radon in the mines were estimated. The mean annual effective dose due to an intake of ⁴⁰K from the salt was calculated as 20.0 ± 11.1 µSv, which is lower than the average annual effective dose rate of 0.29 mSv, received by the ingestion of natural radionuclides. Due to the low concentration values of primordial radionuclides in the salt and radon ²²²Rn) in the mines, a 'low level activity measurement laboratory' is suggested to be established in these mines.

Drought analysis in the Tons River Basin, India during 1969-2008

NASA Astrophysics Data System (ADS)

Meshram, Sarita Gajbhiye; Gautam, Randhir; Kahya, Ercan

2018-05-01

The primary focus of this study is the analysis of droughts in the Tons River Basin during the period 1969-2008. Precipitation data observed at four gauging stations are used to identify drought over the study area. The event of drought is derived from the standardized precipitation index (SPI) on a 3-month scale. Our results indicated that severe drought occurred in the Allahabad, Rewa, and Satna stations in the years 1973 and 1979. The droughts in this region had occurred mainly due to erratic behavior in monsoons, especially due to long breaks between monsoons. During the drought years, the deficiency of the annual rainfall in the analysis of annual rainfall departure had varied from -26% in 1976 to -60% in 1973 at Allahabad station in the basin. The maximum deficiency of annual and seasonal rainfall recorded in the basin is 60%. The maximum seasonal rainfall departure observed in the basin is in the order of -60% at Allahabad station in 1973, while maximum annual rainfall departure had been recorded as -60% during 1979 at the Satna station. Extreme dry events ( z score <-2) were detected during July, August, and September. Moreover, severe dry events were observed in August, September, and October. The drought conditions in the Tons River Basin are dominantly driven by total rainfall throughout the period between June and November.

A further contribution to the seasonal variation of weighted mean temperature

NASA Astrophysics Data System (ADS)

Ding, Maohua; Hu, Wusheng

2017-12-01

The weighted mean temperature Tm is a variable parameter in the Global Navigation Satellite System (GNSS) meteorology and the Askne-Nordius zenith wet delay (ZWD) model. Some parameters about the Tm seasonal variation (e.g. the annual mean value, the annual range, the annual and semi-annual amplitudes, and the long-term trend) were discussed before. In this study, some additional results about the Tm seasonal variation on a global scale were found by using the Tm time series at 309 global radiosonde sites. Periodic signals of the annual and semi-annual variations were detected in these Tm time series by using the Lomb-Scargle periodogram. The annual variation is the main component of the periodic Tm in non-tropical regions, while the annual variation or the semiannual variation can be the main component of the periodic Tm in tropics. The mean annual Tm almost keeps constant with the increasing latitude in tropics, while it decreases with the increasing latitude in non-tropical regions. From a global perspective, Tm has an increasing trend of 0.22 K/decade on average, which may be caused by the global warming effects. The annual phase is almost found in about January for the non-tropical regions of the Southern Hemisphere and in about July for the non-tropical regions of the Northern Hemisphere, but it has no clear symmetry in tropics. Unlike the annual phase, the geographical distributions of semi-annual phase do not follow obvious rules. In non-tropical regions, the maximum and minimum Tm of the seasonal model are usually found in respective summer and winter days while the maximum and minimum Tm are distributed over a whole year but not in any fixed seasons for tropical regions. The seasonal model errors increase with the increasing value of annual amplitude. A primary reason for the irregular seasonal variation in tropics is that Tm has rather small variations in this region.

Volumetric tumor burden and its effect on brachial plexus dosimetry in head and neck intensity-modulated radiotherapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Romesser, Paul B.; Qureshi, Muhammad M.; Kovalchuk, Nataliya

2014-07-01

To determine the effect of gross tumor volume of the primary (GTV-P) and nodal (GTV-N) disease on planned radiation dose to the brachial plexus (BP) in head and neck intensity-modulated radiotherapy (IMRT). Overall, 75 patients underwent definitive IMRT to a median total dose of 69.96 Gy in 33 fractions. The right BP and left BP were prospectively contoured as separate organs at risk. The GTV was related to BP dose using the unpaired t-test. Receiver operating characteristics curves were constructed to determine optimized volumetric thresholds of GTV-P and GTV-N corresponding to a maximum BP dose cutoff of > 66 Gy.more » Multivariate analyses were performed to account for factors associated with a higher maximal BP dose. A higher maximum BP dose (> 66 vs ≤ 66 Gy) correlated with a greater mean GTV-P (79.5 vs 30.8 cc; p = 0.001) and ipsilateral GTV-N (60.6 vs 19.8 cc; p = 0.014). When dichotomized by the optimized nodal volume, patients with an ipsilateral GTV-N ≥ 4.9 vs < 4.9 cc had a significant difference in maximum BP dose (64.2 vs 59.4 Gy; p = 0.001). Multivariate analysis confirmed that an ipsilateral GTV-N ≥ 4.9 cc was an independent predictor for the BP to receive a maximal dose of > 66 Gy when adjusted individually for BP volume, GTV-P, the use of a low anterior neck field technique, total planned radiation dose, and tumor category. Although both the primary and the nodal tumor volumes affected the BP maximal dose, the ipsilateral nodal tumor volume (GTV-N ≥ 4.9 cc) was an independent predictor for high maximal BP dose constraints in head and neck IMRT.« less

Stereotactic body radiation therapy of early-stage non-small-cell lung carcinoma: Phase I study

DOE Office of Scientific and Technical Information (OSTI.GOV)

McGarry, Ronald C.; Papiez, Lech; Williams, Mark

Purpose: A Phase I dose escalation study of stereotactic body radiation therapy to assess toxicity and local control rates for patients with medically inoperable Stage I lung cancer. Methods and Materials: All patients had non-small-cell lung carcinoma, Stage T1a or T1b N0, M0. Patients were immobilized in a stereotactic body frame and treated in escalating doses of radiotherapy beginning at 24 Gy total (3 x 8 Gy fractions) using 7-10 beams. Cohorts were dose escalated by 6.0 Gy total with appropriate observation periods. Results: The maximum tolerated dose was not achieved in the T1 stratum (maximum dose = 60 Gy),more » but within the T2 stratum, the maximum tolerated dose was realized at 72 Gy for tumors larger than 5 cm. Dose-limiting toxicity included predominantly bronchitis, pericardial effusion, hypoxia, and pneumonitis. Local failure occurred in 4/19 T1 and 6/28 T2 patients. Nine local failures occurred at doses {<=}16 Gy and only 1 at higher doses. Local failures occurred between 3 and 31 months from treatment. Within the T1 group, 5 patients had distant or regional recurrence as an isolated event, whereas 3 patients had both distant and regional recurrence. Within the T2 group, 2 patients had solitary regional recurrences, and the 4 patients who failed distantly also failed regionally. Conclusions: Stereotactic body radiation therapy seems to be a safe, effective means of treating early-stage lung cancer in medically inoperable patients. Excellent local control was achieved at higher dose cohorts with apparent dose-limiting toxicities in patients with larger tumors.« less

Exponentially increasing incidences of cutaneous malignant melanoma in Europe correlate with low personal annual UV doses and suggests 2 major risk factors.

PubMed

Merrill, Stephen J; Ashrafi, Samira; Subramanian, Madhan; Godar, Dianne E

2015-01-01

For several decades the incidence of cutaneous malignant melanoma (CMM) steadily increased in fair-skinned, indoor-working people around the world. Scientists think poor tanning ability resulting in sunburns initiate CMM, but they do not understand why the incidence continues to increase despite the increased use of sunscreens and formulations offering more protection. This paradox, along with lower incidences of CMM in outdoor workers, although they have significantly higher annual UV doses than indoor workers have, perplexes scientists. We found a temporal exponential increase in the CMM incidence indicating second-order reaction kinetics revealing the existence of 2 major risk factors. From epidemiology studies, we know one major risk factor for getting CMM is poor tanning ability and we now propose the other major risk factor may be the Human Papilloma Virus (HPV) because clinicians find β HPVs in over half the biopsies. Moreover, we uncovered yet another paradox; the increasing CMM incidences significantly correlate with decreasing personal annual UV dose, a proxy for low vitamin D3 levels. We also discovered the incidence of CMM significantly increased with decreasing personal annual UV dose from 1960, when it was almost insignificant, to 2000. UV and other DNA-damaging agents can activate viruses, and UV-induced cytokines can hide HPV from immune surveillance, which may explain why CMM also occurs in anatomical locations where the sun does not shine. Thus, we propose the 2 major risk factors for getting CMM are intermittent UV exposures that result in low cutaneous levels of vitamin D3 and possibly viral infection.

Indoor and outdoor radon measurements at lung cancer patients' homes in the dwellings of Rize Province in Turkey.

PubMed

Özen, Songül Akbulut; Celik, Necati; Dursun, Emrehan; Taskın, Halim

2018-06-01

In this study, indoor and outdoor radon ( 222 Rn) surveys were carried out in the summer and winter seasons in homes of one hundred lung cancer patients in the year 2013-2014. The aim was to investigate the relationship between radon and cancer patients. Lung cancer patients completed a questionnaire concerning their living environment, various physical parameters and living habits. Pearson correlation and t tests revealed no meaningful results between radon concentrations, on one hand, and environmental and personal living habits, on the other hand. Consequently, the BEIR VI model was adapted and 222 Rn exposure was estimated to be responsible for about 12% of the lung cancer incidences in the winter season and around 5% in the summer season in the Rize Province. However, due to the limited number of data and numerous parameters that could lead to lung cancer, the estimations done with the model should be taken very lightly. The annual effective doses due to inhalation of indoor and outdoor 222 Rn were estimated to be, respectively, 1.43 and 0.94 mSv y -1 . The indoor and outdoor annual effective doses were, respectively, close and below the world annual effective dose (1.3 mSv y -1 ). At the district level, the indoor annual effective dose equivalent in the İyidere district was 4.52 mSv y -1 , which was 3.5 times greater than the world average. The number of patients in the majority of the houses in this district was more than one.

AN ANNUAL EVALUATION OF THE 2005 RELEASE OF MODELS-3 CMAQ

EPA Science Inventory

An annual operation performance evaluation of the 2005 release of Models-3 CMAQ v4.5 has been performed. The poster presented results from the winter and summer season for sulfate, nitrate, ammonium, elemental carbon, organic carbon, PM2.5 mass and AQS 8-hr maximum ozone. Stati...

Descriptive Statistics and Cluster Analysis for Extreme Rainfall in Java Island

NASA Astrophysics Data System (ADS)

E Komalasari, K.; Pawitan, H.; Faqih, A.

2017-03-01

This study aims to describe regional pattern of extreme rainfall based on maximum daily rainfall for period 1983 to 2012 in Java Island. Descriptive statistics analysis was performed to obtain centralization, variation and distribution of maximum precipitation data. Mean and median are utilized to measure central tendency data while Inter Quartile Range (IQR) and standard deviation are utilized to measure variation of data. In addition, skewness and kurtosis used to obtain shape the distribution of rainfall data. Cluster analysis using squared euclidean distance and ward method is applied to perform regional grouping. Result of this study show that mean (average) of maximum daily rainfall in Java Region during period 1983-2012 is around 80-181mm with median between 75-160mm and standard deviation between 17 to 82. Cluster analysis produces four clusters and show that western area of Java tent to have a higher annual maxima of daily rainfall than northern area, and have more variety of annual maximum value.

Fetal radiation dose estimates for I-131 sodium iodide in cases where conception occurs after administration

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sparks, R.B.; Stabin, M.G.

1999-01-01

After administration of I-131 to the female patient, the possibility of radiation exposure of the embryo/fetus exists if the patient becomes pregnant while radioiodine remains in the body. Fetal radiation dose estimates for such cases were calculated. Doses were calculated for various maternal thyroid uptakes and time intervals between administration and conception, including euthyroid and hyperthyroid cases. The maximum fetal dose calculating was about 9.8E-03 mGy/MBq, which occurred with 100% maternal thyroid uptake and a 1 week interval between administration and conception. Placental crossover of the small amount of radioiodine remaining 90 days after conception was also considered. Such crossovermore » could result in an additional fetal dose of 9.8E-05 mGy/MBq and a maximum fetal thyroid self dose of 3.5E-04 mGy/MBq.« less

In vivo dosimetry for external photon treatments of head and neck cancers by diodes and TLDS.

PubMed

Tung, C J; Wang, H C; Lo, S H; Wu, J M; Wang, C J

2004-01-01

In vivo dosimetry was implemented for treatments of head and neck cancers in the large fields. Diode and thermoluminescence dosemeter (TLD) measurements were carried out for the linear accelerators of 6 MV photon beams. ESTRO in vivo dosimetry protocols were followed in the determination of midline doses from measurements of entrance and exit doses. Of the fields monitored by diodes, the maximum absolute deviation of measured midline doses from planned target doses was 8%, with the mean value and the standard deviation of -1.0 and 2.7%. If planned target doses were calculated using radiological water equivalent thicknesses rather than patient geometric thicknesses, the maximum absolute deviation dropped to 4%, with the mean and the standard deviation of 0.7 and 1.8%. For in vivo dosimetry monitored by TLDs, the shift in mean dose remained small but the statistical precision became poor.

Whole-remnant and maximum-voxel SPECT/CT dosimetry in {sup 131}I-NaI treatments of differentiated thyroid cancer

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mínguez, Pablo, E-mail: pablo.minguezgabina@osakid

Purpose: To investigate the possible differences between SPECT/CT based whole-remnant and maximum-voxel dosimetry in patients receiving radio-iodine ablation treatment of differentiated thyroid cancer (DTC). Methods: Eighteen DTC patients were administered 1.11 GBq of {sup 131}I-NaI after near-total thyroidectomy and rhTSH stimulation. Two patients had two remnants, so in total dosimetry was performed for 20 sites. Three SPECT/CT scans were performed for each patient at 1, 2, and 3–7 days after administration. The activity, the remnant mass, and the maximum-voxel activity were determined from these images and from a recovery-coefficient curve derived from experimental phantom measurements. The cumulated activity was estimatedmore » using trapezoidal-exponential integration. Finally, the absorbed dose was calculated using S-values for unit-density spheres in whole-remnant dosimetry and S-values for voxels in maximum-voxel dosimetry. Results: The mean absorbed dose obtained from whole-remnant dosimetry was 40 Gy (range 2–176 Gy) and from maximum-voxel dosimetry 34 Gy (range 2–145 Gy). For any given patient, the activity concentrations for each of the three time-points were approximately the same for the two methods. The effective half-lives varied (R = 0.865), mainly due to discrepancies in estimation of the longer effective half-lives. On average, absorbed doses obtained from whole-remnant dosimetry were 1.2 ± 0.2 (1 SD) higher than for maximum-voxel dosimetry, mainly due to differences in the S-values. The method-related differences were however small in comparison to the wide range of absorbed doses obtained in patients. Conclusions: Simple and consistent procedures for SPECT/CT based whole-volume and maximum-voxel dosimetry have been described, both based on experimentally determined recovery coefficients. Generally the results from the two approaches are consistent, although there is a small, systematic difference in the absorbed dose due to differences in the S-values, and some variability due to differences in the estimated effective half-lives, especially when the effective half-life is long. Irrespective of the method used, the patient absorbed doses obtained span over two orders of magnitude.« less

CT Fluoroscopy Shielding: Decreases in Scattered Radiation for the Patient and Operator

PubMed Central

Neeman, Ziv; Dromi, Sergio A.; Sarin, Shawn; Wood, Bradford J.

2008-01-01

PURPOSE High-radiation exposure occurs during computed tomographic (CT) fluoroscopy. Patient and operator doses during thoracic and abdominal interventional procedures were studied in the present experiment, and a novel shielding device to reduce exposure to the patient and operator was evaluated. MATERIALS AND METHODS With a 16-slice CT scanner in CT fluoroscopy mode (120 kVp, 30 mA), surface dosimetry was performed on adult and pediatric phantoms. The shielding was composed of tungsten antimony in the form of a lightweight polymer sheet. Doses to the patient were measured with and without shielding for thoracic and abdominal procedures. Doses to the operator were recorded with and without phantom, gantry, and table shielding in place. Double-layer lead-free gloves were used by the operator during the procedures. RESULTS Tungsten antimony shielding adjacent to the scan plane resulted in a maximum dose reduction of 92.3% to the patient. Maximum 85.6%, 93.3%, and 85.1% dose reductions were observed for the operator’s torso, gonads, and hands, respectively. The use of double-layer lead-free gloves resulted in a maximum radiation dose reduction of 97%. CONCLUSIONS Methods to reduce exposure during CT fluoroscopy are effective and should be searched for. Significant reduction in radiation doses to the patient and operator can be accomplished with tungsten antimony shielding. PMID:17185699

Estimation of Reineke and Volume-Based Maximum Size-Density Lines For Shortleaf Pine

Treesearch

Thomas B. Lynch; Robert F. Wittwer; Douglas J. Stevenson

2004-01-01

Maximum size-density relationships for Reineke's stand density index as well as for a relationship based on average tree volume were fitted to data from more than a decade of annual remeasurements of plots in unthinned naturally occurring shor tleaf pine in southeaster n Oklahoma. Reineke's stand density index is based on a maximum line of the form log(N) = a...

Cosmic ray modulation and radiation dose of aircrews during the solar cycle 24/25

NASA Astrophysics Data System (ADS)

Miyake, Shoko; Kataoka, Ryuho; Sato, Tatsuhiko

2017-04-01

Weak solar activity and high cosmic ray flux during the coming solar cycle are qualitatively anticipated by the recent observations that show the decline in the solar activity levels. We predict the cosmic ray modulation and resultant radiation exposure at flight altitude by using the time-dependent and three-dimensional model of the cosmic ray modulation. Our galactic cosmic ray (GCR) model is based on the variations of the solar wind speed, the strength of the heliospheric magnetic field, and the tilt angle of the heliospheric current sheet. We reproduce the 22 year variation of the cosmic ray modulation from 1980 to 2015 taking into account the gradient-curvature drift motion of GCRs. The energy spectra of GCR protons obtained by our model show good agreement with the observations by the Balloon-borne Experiment with a Superconducting magnetic rigidity Spectrometer (BESS) and the Payload for Antimatter Matter Exploration and Light-nuclei Astrophysics (PAMELA) except for a discrepancy at the solar maximum. Five-year annual radiation dose around the solar minimum at the solar cycle 24/25 will be approximately 19% higher than that in the last cycle. This is caused by the charge sign dependence of the cosmic ray modulation, such as the flattop profiles in a positive polarity.

Using quality of life measures in a Phase I clinical trial of noni in patients with advanced cancer to select a Phase II dose.

PubMed

Issell, Brian F; Gotay, Carolyn C; Pagano, Ian; Franke, Adrian A

2009-01-01

ABSTRACT. The purpose of this study was to determine a maximum tolerated dose of noni in cancer patients and whether an optimal quality of life-sustaining dose could be identified as an alternative way to select a dose for subsequent Phase II efficacy trials. Dose levels started at two capsules twice daily (2 g), the suggested dose for the marketed product, and were escalated by 2 g daily in cohorts of at least five patients until a maximum tolerated dose was found. Patients completed subscales of the European Organization for Research and Treatment of Cancer (EORTC) QLQ-C30 quality of life (physical functioning, pain, and fatigue) the brief fatigue inventory (BFI), questionnaires at baseline and at approximately 4-week intervals. Blood and urine were collected at baseline and at approximately 4-week intervals for measurement of scopoletin. Fifty-one patients were enrolled at seven dose levels. The maximum tolerated dose was six capsules four times daily (12 g). Although no dose-limiting toxicity was found, seven of eight patients at the next level (14 g), withdrew due to the challenges of ingesting so many capsules. There were dose-related differences in self-reported physical functioning and pain and fatigue control. Overall, patients taking three or four capsules four times daily experienced better outcomes than patients taking lower or higher doses. Blood and urinary scopoletin concentrations related to noni dose. We concluded that it is feasible to use quality of life measures to select a Phase II dose. Three or four capsules four times daily (6-8 g) is recommended when controlling fatigue, pain, and maintaining physical function are the efficacies of interest. Scopoletin, a bioactive component of noni fruit extract, is measurable in blood and urine following noni ingestion and can be used to study the pharmacokinetics of noni in cancer patients.

Report of the annual yield of the Arkansas River basin for the Arkansas River Basin Compact, Arkansas-Oklahoma,1983 water year

USGS Publications Warehouse

Moore, M.A.; Lamb, T.E.

1984-01-01

The computed annual yield and deficiency of the subbasins as defined in the Arkansas River Compact, Arkansas-Oklahoma, are given in tables. Actual runoff from the subbasins and depletion caused by major reservoirs in the compact area are also given in tabular form. Monthly, maximum, minimum, and mean discharges are shown for the 14 streamflow stations used in computing annual yield. (USGS)

Analysis of meteorological droughts and dry spells in semiarid regions: a comparative analysis of probability distribution functions in the Segura Basin (SE Spain)

NASA Astrophysics Data System (ADS)

Pérez-Sánchez, Julio; Senent-Aparicio, Javier

2017-08-01

Dry spells are an essential concept of drought climatology that clearly defines the semiarid Mediterranean environment and whose consequences are a defining feature for an ecosystem, so vulnerable with regard to water. The present study was conducted to characterize rainfall drought in the Segura River basin located in eastern Spain, marked by the self seasonal nature of these latitudes. A daily precipitation set has been utilized for 29 weather stations during a period of 20 years (1993-2013). Furthermore, four sets of dry spell length (complete series, monthly maximum, seasonal maximum, and annual maximum) are used and simulated for all the weather stations with the following probability distribution functions: Burr, Dagum, error, generalized extreme value, generalized logistic, generalized Pareto, Gumbel Max, inverse Gaussian, Johnson SB, Log-Logistic, Log-Pearson 3, Triangular, Weibull, and Wakeby. Only the series of annual maximum spell offer a good adjustment for all the weather stations, thereby gaining the role of Wakeby as the best result, with a p value means of 0.9424 for the Kolmogorov-Smirnov test (0.2 significance level). Probability of dry spell duration for return periods of 2, 5, 10, and 25 years maps reveal the northeast-southeast gradient, increasing periods with annual rainfall of less than 0.1 mm in the eastern third of the basin, in the proximity of the Mediterranean slope.

SU-G-201-08: Energy Response of Thermoluminescent Microcube Dosimeters in Water for Kilovoltage X-Ray Beams

DOE Office of Scientific and Technical Information (OSTI.GOV)

Di Maso, L; Lawless, M; Culberson, W

Purpose: To characterize the energy dependence for TLD-100 microcubes in water at kilovoltage energies. Methods: TLD-100 microcubes with dimensions of (1 × 1 × 1) mm{sup 3} were irradiated with kilovoltage x-rays in a custom-built thin-window liquid water phantom. The TLD-100 microcubes were held in Virtual Water™ probes and aligned at a 2 cm depth in water. Irradiations were performed using the M-series x-ray beams of energies ranging from 50-250 kVp and normalized to a {sup 60}Co beam located at the UWADCL. Simulations using the EGSnrc Monte Carlo Code System were performed to model the x-ray beams, the {sup 60}Comore » beam, the water phantom and the dosimeters in the phantom. The egs-chamber user code was used to tally the dose to the TLDs and the dose to water. The measurements and calculations were used to determine the intrinsic energy dependence, absorbed-dose energy dependence, and absorbed-dose sensitivity. These values were compared to TLD-100 chips with dimensions of (3.2 × 0.9 × 0.9) mm{sup 3}. Results: The measured TLD-100 microcube response per dose to water among all investigated x-ray energies had a maximum percent difference of 61% relative to {sup 60}Co. The simulated ratio of dose to water to the dose to TLD had a maximum percent difference of 29% relative to {sup 60}Co. The ratio of dose to TLD to the TLD output had a maximum percent difference of 13% relative to {sup 60}Co. The maximum percent difference for the absorbed-dose sensitivity was 15% more than the used value of 1.41. Conclusion: These results confirm that differences in beam quality have a significant effect on TLD response when irradiated in water. These results also indicated a difference in TLD-100 response between microcube and chip geometries. The intrinsic energy dependence and the absorbed-dose energy dependence deviated up to 10% between TLD-100 microcubes and chips.« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lafata, K; Ren, L; Wu, Q

Purpose: To develop a data-mining methodology based on quantum clustering and machine learning to predict expected dosimetric endpoints for lung SBRT applications based on patient-specific anatomic features. Methods: Ninety-three patients who received lung SBRT at our clinic from 2011–2013 were retrospectively identified. Planning information was acquired for each patient, from which various features were extracted using in-house semi-automatic software. Anatomic features included tumor-to-OAR distances, tumor location, total-lung-volume, GTV and ITV. Dosimetric endpoints were adopted from RTOG-0195 recommendations, and consisted of various OAR-specific partial-volume doses and maximum point-doses. First, PCA analysis and unsupervised quantum-clustering was used to explore the feature-space tomore » identify potentially strong classifiers. Secondly, a multi-class logistic regression algorithm was developed and trained to predict dose-volume endpoints based on patient-specific anatomic features. Classes were defined by discretizing the dose-volume data, and the feature-space was zero-mean normalized. Fitting parameters were determined by minimizing a regularized cost function, and optimization was performed via gradient descent. As a pilot study, the model was tested on two esophageal dosimetric planning endpoints (maximum point-dose, dose-to-5cc), and its generalizability was evaluated with leave-one-out cross-validation. Results: Quantum-Clustering demonstrated a strong separation of feature-space at 15Gy across the first-and-second Principle Components of the data when the dosimetric endpoints were retrospectively identified. Maximum point dose prediction to the esophagus demonstrated a cross-validation accuracy of 87%, and the maximum dose to 5cc demonstrated a respective value of 79%. The largest optimized weighting factor was placed on GTV-to-esophagus distance (a factor of 10 greater than the second largest weighting factor), indicating an intuitively strong correlation between this feature and both endpoints. Conclusion: This pilot study shows that it is feasible to predict dose-volume endpoints based on patient-specific anatomic features. The developed methodology can potentially help to identify patients at risk for higher OAR doses, thus improving the efficiency of treatment planning. R01-184173.« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

Park, J; Kim, J; Park, S

Purpose: To investigate exposure outside the treatment field when treating breast cancer with tri-Co-60 magnetic resonance (MR) image guided radiation therapy (IGRT) system. Methods: A total of 7 patients who treated with accelerated partial breast irradiation (APBI) technique were selected prospectively for this study (prescription dose = 38.5 Gy in 10 fractions). Every patient treated with two plans, one was an initial plan and the other was an adaptive plan generated after finishing 5 fractions (a total of 14 plans). Every plan was calculated with and without magnetic field in the treatment planning system. The EBT3 films were attached onmore » the front and the back of 1 cm bolus, and then it was placed on the patient body vertically to cover patient’s jaw and shoulder. After measurements, the maximum point dose and the mean dose of whole area of EBT3 film were acquired. Results: In the treatment plan with magnetic field, low dose stream outside the patient body was observed, almost reaching the patient’s jaw or shoulder, while it was not observed without magnetic field. The average values of the measured maximum and mean doses at the front of bolus were 30.1 ± 11.1 cGy (7.8% of the daily dose) and 14.7 ± 3.3 cGy (3.8%), respectively. At the back of bolus, those values were 6.0 ± 1.9 cGy (1.6%) and 5.1 ± 1.6 cGy (1.3%), respectively. The largest maximum dose at the front was 54.2 cGy (14.1%) while it was 20.7 cGy (5.4%) at the back. The average decrease of the maximum dose by the bolus was 24.0 ± 11.0 cGy. Conclusion: Due to magnetic field, dose stream outside the patient body can be generated during breast cancer treatment with the tri-Co-60 MR-IGRT system. Since this dose stream irradiated skin outside the treatment field, it should be shielded. This work was supported by the National Research Foundation of Korea (NRF) grant funded by the Korea government (MSIP) (No. 2015R1C1A1A01054192).« less

Prediction of Normal Organ Absorbed Doses for [177Lu]Lu-PSMA-617 Using [44Sc]Sc-PSMA-617 Pharmacokinetics in Patients With Metastatic Castration Resistant Prostate Carcinoma.

PubMed

Khawar, Ambreen; Eppard, Elisabeth; Sinnes, Jean Phlippe; Roesch, Frank; Ahmadzadehfar, Hojjat; Kürpig, Stefan; Meisenheimer, Michael; Gaertner, Florian C; Essler, Markus; Bundschuh, Ralph A

2018-04-23

In vivo pharmacokinetic analysis of [Sc]Sc-PSMA-617 was used to determine the normal organ-absorbed doses that may result from therapeutic activity of [Lu]Lu-PSMA-617 and to predict the maximum permissible activity of [Lu]Lu-PSMA-617 for patients with metastatic castration-resistant prostate carcinoma. Pharmacokinetics of [Sc]Sc-PSMA-617 was evaluated in 5 patients with metastatic castration-resistant prostate carcinoma using dynamic PET/CT, followed by 3 static PET/CT acquisitions and blood sample collection over 19.5 hours, as well as urine sample collection at 2 time points. Total activity measured in source organs by PET imaging, as well as counts per milliliter measured in blood and urine samples, was decay corrected back to the time of injection using the half-life of Sc. Afterward, forward decay correction using the half-life of Lu was performed, extrapolating the pharmacokinetics of [Sc]Sc-PSMA-617 to that of [Lu]Lu-PSMA-617. Source organs residence times and organ-absorbed doses for [Lu]Lu-PSMA-617 were calculated using OLINDA/EXM software. Bone marrow self-dose was determined with indirect blood-based method, and urinary bladder contents residence time was estimated by trapezoidal approximation. The maximum permissible activity of [Lu]Lu-PSMA-617 was calculated for each patient considering external beam radiotherapy toxicity limits for radiation absorbed doses to kidneys, bone marrow, salivary glands, and whole body. The predicted mean organ-absorbed doses were highest in the kidneys (0.44 mSv/MBq), followed by the salivary glands (0.23 mSv/MBq). The maximum permissible activity was highly variable among patients; limited by whole body-absorbed dose (1 patient), marrow-absorbed dose (1 patient), and kidney-absorbed dose (3 patients). [Sc]Sc-PSMA-617 PET/CT imaging is feasible and allows theoretical extrapolation of the pharmacokinetics of [Sc]Sc-PSMA-617 to that of [Lu]Lu-PSMA-617, with the intent of predicting normal organ-absorbed doses and maximum permissible activity in patients scheduled for therapy with [Lu]Lu-PSMA-617.

2015 Arctic Sea Ice Maximum Annual Extent Is Lowest On Record

NASA Image and Video Library

2015-03-19

The sea ice cap of the Arctic appeared to reach its annual maximum winter extent on Feb. 25, according to data from the NASA-supported National Snow and Ice Data Center (NSIDC) at the University of Colorado, Boulder. At 5.61 million square miles (14.54 million square kilometers), this year’s maximum extent was the smallest on the satellite record and also one of the earliest. Read more: 1.usa.gov/1Eyvelz Credit: NASA's Goddard Space Flight Center NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

VMAT testing for an Elekta accelerator

PubMed Central

Sweeney, Larry E.; Marshall, Edward I.; Mahendra, Saikanth

2012-01-01

Volumetric‐modulated arc therapy (VMAT) has been shown to be able to deliver plans equivalent to intensity‐modulated radiation therapy (IMRT) in a fraction of the treatment time. This improvement is important for patient immobilization/ localization compliance due to comfort and treatment duration, as well as patient throughput. Previous authors have suggested commissioning methods for this modality. Here, we extend the methods reported for the Varian RapidArc system (which tested individual system components) to the Elekta linear accelerator, using custom files built using the Elekta iComCAT software. We also extend the method reported for VMAT commissioning of the Elekta accelerator by verifying maximum values of parameters (gantry speed, multileaf collimator (MLC) speed, and backup jaw speed), investigating: 1) beam profiles as a function of dose rate during an arc, 2) over/under dosing due to MLC reversals, and 3) over/under dosing at changing dose rate junctions. Equations for construction of the iComCAT files are given. Results indicate that the beam profile for lower dose rates varies less than 3% from that of the maximum dose rate, with no difference during an arc. The gantry, MLC, and backup jaw maximum speed are internally consistent. The monitor unit chamber is stable over the MUs and gantry movement conditions expected. MLC movement and position during VMAT delivery are within IMRT tolerances. Dose rate, gantry speed, and MLC speed are accurately controlled. Over/under dosing at junctions of MLC reversals or dose rate changes are within clinical acceptability. PACS numbers: 87.55.de, 87.55.Qr, 87.56.bd PMID:22402389

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bosarge, Christina L., E-mail: cbosarge@umail.iu.edu; Ewing, Marvene M.; DesRosiers, Colleen M.

To demonstrate the dosimetric advantages and disadvantages of standard anteroposterior-posteroanterior (S-AP/PA{sub AAA}), inverse-planned AP/PA (IP-AP/PA) and volumetry-modulated arc (VMAT) radiotherapies in the treatment of children undergoing whole-lung irradiation. Each technique was evaluated by means of target coverage and normal tissue sparing, including data regarding low doses. A historical approach with and without tissue heterogeneity corrections is also demonstrated. Computed tomography (CT) scans of 10 children scanned from the neck to the reproductive organs were used. For each scan, 6 plans were created: (1) S-AP/PA{sub AAA} using the anisotropic analytical algorithm (AAA), (2) IP-AP/PA, (3) VMAT, (4) S-AP/PA{sub NONE} without heterogeneitymore » corrections, (5) S-AP/PA{sub PB} using the Pencil-Beam algorithm and enforcing monitor units from technique 4, and (6) S-AP/PA{sub AAA[FM]} using AAA and forcing fixed monitor units. The first 3 plans compare modern methods and were evaluated based on target coverage and normal tissue sparing. Body maximum and lower body doses (50% and 30%) were also analyzed. Plans 4 to 6 provide a historic view on the progression of heterogeneity algorithms and elucidate what was actually delivered in the past. Averages of each comparison parameter were calculated for all techniques. The S-AP/PA{sub AAA} technique resulted in superior target coverage but had the highest maximum dose to every normal tissue structure. The IP-AP/PA technique provided the lowest dose to the esophagus, stomach, and lower body doses. VMAT excelled at body maximum dose and maximum doses to the heart, spine, and spleen, but resulted in the highest dose in the 30% body range. It was, however, superior to the S-AP/PA{sub AAA} approach in the 50% range. Each approach has strengths and weaknesses thus associated. Techniques may be selected on a case-by-case basis and by physician preference of target coverage vs normal tissue sparing.« less

SU-E-T-578: On Definition of Minimum and Maximum Dose for Target Volume

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gong, Y; Yu, J; Xiao, Y

Purpose: This study aims to investigate the impact of different minimum and maximum dose definitions in radiotherapy treatment plan quality evaluation criteria by using tumor control probability (TCP) models. Methods: Dosimetric criteria used in RTOG 1308 protocol are used in the investigation. RTOG 1308 is a phase III randomized trial comparing overall survival after photon versus proton chemoradiotherapy for inoperable stage II-IIIB NSCLC. The prescription dose for planning target volume (PTV) is 70Gy. Maximum dose (Dmax) should not exceed 84Gy and minimum dose (Dmin) should not go below 59.5Gy in order for the plan to be “per protocol” (satisfactory).A mathematicalmore » model that simulates the characteristics of PTV dose volume histogram (DVH) curve with normalized volume is built. The Dmax and Dmin are noted as percentage volumes Dη% and D(100-δ)%, with η and d ranging from 0 to 3.5. The model includes three straight line sections and goes through four points: D95%= 70Gy, Dη%= 84Gy, D(100-δ)%= 59.5 Gy, and D100%= 0Gy. For each set of η and δ, the TCP value is calculated using the inhomogeneously irradiated tumor logistic model with D50= 74.5Gy and γ50=3.52. Results: TCP varies within 0.9% with η; and δ values between 0 and 1. With η and η varies between 0 and 2, TCP change was up to 2.4%. With η and δ variations from 0 to 3.5, maximum of 8.3% TCP difference is seen. Conclusion: When defined maximum and minimum volume varied more than 2%, significant TCP variations were seen. It is recommended less than 2% volume used in definition of Dmax or Dmin for target dosimetric evaluation criteria. This project was supported by NIH grants U10CA180868, U10CA180822, U24CA180803, U24CA12014 and PA CURE Grant.« less

Global-scale high-resolution ( 1 km) modelling of mean, maximum and minimum annual streamflow

NASA Astrophysics Data System (ADS)

Barbarossa, Valerio; Huijbregts, Mark; Hendriks, Jan; Beusen, Arthur; Clavreul, Julie; King, Henry; Schipper, Aafke

2017-04-01

Quantifying mean, maximum and minimum annual flow (AF) of rivers at ungauged sites is essential for a number of applications, including assessments of global water supply, ecosystem integrity and water footprints. AF metrics can be quantified with spatially explicit process-based models, which might be overly time-consuming and data-intensive for this purpose, or with empirical regression models that predict AF metrics based on climate and catchment characteristics. Yet, so far, regression models have mostly been developed at a regional scale and the extent to which they can be extrapolated to other regions is not known. We developed global-scale regression models that quantify mean, maximum and minimum AF as function of catchment area and catchment-averaged slope, elevation, and mean, maximum and minimum annual precipitation and air temperature. We then used these models to obtain global 30 arc-seconds (˜ 1 km) maps of mean, maximum and minimum AF for each year from 1960 through 2015, based on a newly developed hydrologically conditioned digital elevation model. We calibrated our regression models based on observations of discharge and catchment characteristics from about 4,000 catchments worldwide, ranging from 100 to 106 km2 in size, and validated them against independent measurements as well as the output of a number of process-based global hydrological models (GHMs). The variance explained by our regression models ranged up to 90% and the performance of the models compared well with the performance of existing GHMs. Yet, our AF maps provide a level of spatial detail that cannot yet be achieved by current GHMs.

Actividad solar del ciclo 23. Predicción del máximo y fase decreciente utilizando redes neuronales

NASA Astrophysics Data System (ADS)

Parodi, M. A.; Ceccatto, H. A.; Piacentini, R. D.; García, P. J.

Different methods have been proposed in order to predict the maximum amplitude of solar cycles, either as a consequence of the intrinsic importance of this event and because of its relation with solar storms and possible effects upon satellites, communication systems, etc. In this work, a neural network solar activity prediction is presented, measured through the sunspot number (SSN). The 16-units neural network, with a 12:3:1 architecture, was trained in a ``feed-forward" propagation way and learning by the so called ``back propagation rule". The annual mean SSN data in the 1700-1975 and 1987-1998 periods were used as the training set. The solar cycle 21 (1976-1986) was taken as the cross-validation data set. After performing the network training we obtained a prediction of the maximum annual mean for the current solar cycle 23, SSNmax= 135 ±17 at the year 2000, which is 13% smaller than the International Consensus Commitee's mean maximum prediction obtained through ``precursor techniques". On the other hand, our prediction is only about 4% smaller than the Consensus's neural network mean prediction. A ``multiple step" prediction technique was also performed and SSN annual mean predicted values for the near-maximum (from the present year 1999 to beyond the maximum) and the declining activity of solar cycle 23 are presented in this work. The sensibility of predictions is also tested. To do so, we changed the interval width and comparated our results with those of a previous neural network prediction and those of others authors using differents methods.

OCCURRENCE OF HIGH-SPEED SOLAR WIND STREAMS OVER THE GRAND MODERN MAXIMUM

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mursula, K.; Holappa, L.; Lukianova, R., E-mail: kalevi.mursula@oulu.fi

2015-03-01

In the declining phase of the solar cycle (SC), when the new-polarity fields of the solar poles are strengthened by the transport of same-signed magnetic flux from lower latitudes, the polar coronal holes expand and form non-axisymmetric extensions toward the solar equator. These extensions enhance the occurrence of high-speed solar wind (SW) streams (HSS) and related co-rotating interaction regions in the low-latitude heliosphere, and cause moderate, recurrent geomagnetic activity (GA) in the near-Earth space. Here, using a novel definition of GA at high (polar cap) latitudes and the longest record of magnetic observations at a polar cap station, we calculatemore » the annually averaged SW speeds as proxies for the effective annual occurrence of HSS over the whole Grand Modern Maximum (GMM) from 1920s onward. We find that a period of high annual speeds (frequent occurrence of HSS) occurs in the declining phase of each of SCs 16-23. For most cycles the HSS activity clearly reaches a maximum in one year, suggesting that typically only one strong activation leading to a coronal hole extension is responsible for the HSS maximum. We find that the most persistent HSS activity occurred in the declining phase of SC 18. This suggests that cycle 19, which marks the sunspot maximum period of the GMM, was preceded by exceptionally strong polar fields during the previous sunspot minimum. This gives interesting support for the validity of solar dynamo theory during this dramatic period of solar magnetism.« less

Patient doses in the healing arts

DOE Office of Scientific and Technical Information (OSTI.GOV)

NONE

Determinations of radiation doses to patients from x-ray procedures and radiopharmaceuticals are detailed in this chapter. Instructions are given for estimating doses from x-ray procedures. For selected pediatric procedures, the methodology developed by the Food and Drug Administration is presented. The effect of testicular and ovarian shielding is illustrated in tabular form. Estimates of the Genetically Significant Dose (GSD) and mean annual bone marrow dose from diagnostic x-ray examinations are presented for the US populations (1990). This chapter also provides tables of patient doses from selected nuclear medicine procedures and estimates of fetal doses from {sup 131}I.

Is it useful to assess annual effective doses that are less than 100 mSv?

DOE Office of Scientific and Technical Information (OSTI.GOV)

Strom, Daniel J.; Cameron, John R.

It is useful to assess annual effective doses less than 100 mSv. Beyond the''score-keeping'' needs of regulatory compliance, there are at least seven other valid reasons for performing personnel monitoring, many of which fall into the category of''no news is good news,'' or more aptly,''null news, as long as you can prove it, is good news.'' These are performance measures for contractual compliance, diagnosis of problems with radiation protection programs, health surveillance and occupational epidemiology, prevention of and support for litigation, demonstration of management commitment and safety, worker counseling, ensuring peace of mind. Furthermore, it is shown that there ismore » very reasonable expectation that detriment may be associated with doses smaller than 100 mSv per year.« less

38 CFR 3.27 - Automatic adjustment of benefit rates.

Code of Federal Regulations, 2011 CFR

2011-07-01

... ADJUDICATION Pension, Compensation, and Dependency and Indemnity Compensation General § 3.27 Automatic... pension. (Authority: 38 U.S.C. 5312(a)) (b) Parents' dependency and indemnity compensation—maximum annual... the maximum monthly rates of dependency indemnity compensation for parents. (Authority: 38 U.S.C. 5312...

38 CFR 3.27 - Automatic adjustment of benefit rates.

Code of Federal Regulations, 2013 CFR

2013-07-01

... ADJUDICATION Pension, Compensation, and Dependency and Indemnity Compensation General § 3.27 Automatic... pension. (Authority: 38 U.S.C. 5312(a)) (b) Parents' dependency and indemnity compensation—maximum annual... the maximum monthly rates of dependency indemnity compensation for parents. (Authority: 38 U.S.C. 5312...

38 CFR 3.27 - Automatic adjustment of benefit rates.

Code of Federal Regulations, 2010 CFR

2010-07-01

... ADJUDICATION Pension, Compensation, and Dependency and Indemnity Compensation General § 3.27 Automatic... pension. (Authority: 38 U.S.C. 5312(a)) (b) Parents' dependency and indemnity compensation—maximum annual... the maximum monthly rates of dependency indemnity compensation for parents. (Authority: 38 U.S.C. 5312...

38 CFR 3.27 - Automatic adjustment of benefit rates.

Code of Federal Regulations, 2014 CFR

2014-07-01

... ADJUDICATION Pension, Compensation, and Dependency and Indemnity Compensation General § 3.27 Automatic... pension. (Authority: 38 U.S.C. 5312(a)) (b) Parents' dependency and indemnity compensation—maximum annual... the maximum monthly rates of dependency indemnity compensation for parents. (Authority: 38 U.S.C. 5312...

38 CFR 3.27 - Automatic adjustment of benefit rates.

Code of Federal Regulations, 2012 CFR

2012-07-01

... ADJUDICATION Pension, Compensation, and Dependency and Indemnity Compensation General § 3.27 Automatic... pension. (Authority: 38 U.S.C. 5312(a)) (b) Parents' dependency and indemnity compensation—maximum annual... the maximum monthly rates of dependency indemnity compensation for parents. (Authority: 38 U.S.C. 5312...

Volumetric-modulated arc therapy (VMAT) for whole brain radiotherapy: not only for hippocampal sparing, but also for reduction of dose to organs at risk.

PubMed

Sood, Sumit; Pokhrel, Damodar; McClinton, Christopher; Lominska, Christopher; Badkul, Rajeev; Jiang, Hongyu; Wang, Fen

2017-01-01

A prospective clinical trial, Radiation Therapy Oncology Group (RTOG) 0933, has demonstrated that whole brain radiotherapy (WBRT) using conformal radiation delivery technique with hippocampal avoidance is associated with less memory complications. Further sparing of other organs at risk (OARs) including the scalp, ear canals, cochleae, and parotid glands could be associated with reductions in additional toxicities for patients treated with WBRT. We investigated the feasibility of WBRT using volumetric-modulated arc therapy (VMAT) to spare the hippocampi and the aforementioned OARs. Ten patients previously treated with nonconformal WBRT (NC-WBRT) using opposed lateral beams were retrospectively re-planned using VMAT with hippocampal sparing according to the RTOG 0933 protocol. The OARs (scalp, auditory canals, cochleae, and parotid glands) were considered as dose-constrained structures. VMAT plans were generated for a prescription dose of 30 Gy in 10 fractions. Comparison of the dosimetric parameters achieved by VMAT and NC-WBRT plans was performed using paired t-tests using upper bound p-value of < 0.001. Average beam on time and monitor units (MUs) delivered to the patients on VMAT were compared with those obtained with NC-WBRT. All VMAT plans met RTOG 0933 dosimetric criteria including the dose to hippocampi of 100% of the volume (D 100% ) of 8.4 ± 0.3 Gy and maximum dose of 15.6 ± 0.4 Gy, respectively. A statistically significant dose reduction (p < 0.001) to all OARs was achieved. The mean and maximum scalp doses were reduced by an average of 9 Gy (32%) and 2 Gy (6%), respectively. The mean and maximum doses to the auditory canals were reduced from 29.5 ± 0.5 Gy and 31.0 ± 0.4 Gy with NC-WBRT, to 21.8 ± 1.6 Gy (26%) and 27.4 ± 1.4 Gy (12%) with VMAT. VMAT also reduced mean and maximum doses to the cochlea by an average of 4 Gy (13%) and 2 Gy (6%), respectively. The parotid glands mean and maximum doses with VMAT were 4.4 ± 1.9 Gy and 15.7 ± 5.0 Gy, compared to 12.8 ± 4.9 Gy and 30.6 ± 0.5 Gy with NC-WBRT, respectively. The average dose reduction of mean and maximum of parotid glands from VMAT were 65% and 50%, respectively. The average beam on time and MUs were 2.3minutes and 719 on VMAT, and 0.7 minutes and 350 on NC-WBRT. This study demonstrated the feasibility of WBRT using VMAT to not only spare the hippocampi, but also significantly reduce dose to OARs. These advantages of VMAT could potentially decrease the toxicities associated with NC-WBRT and improve patients' quality of life, especially for patients with favorable prognosis receiving WBRT or patients receiving prophylactic cranial irradiation (PCI). Published by Elsevier Inc.

A phase I study with neratinib (HKI-272), an irreversible pan ErbB receptor tyrosine kinase inhibitor, in patients with solid tumors.

PubMed

Wong, Kwok-K; Fracasso, Paula M; Bukowski, Ronald M; Lynch, Thomas J; Munster, Pamela N; Shapiro, Geoffrey I; Jänne, Pasi A; Eder, Joseph P; Naughton, Michael J; Ellis, Matthew J; Jones, Suzanne F; Mekhail, Tarek; Zacharchuk, Charles; Vermette, Jennifer; Abbas, Richat; Quinn, Susan; Powell, Christine; Burris, Howard A

2009-04-01

The dose-limiting toxicities, maximum tolerated dose, pharmacokinetic profile, and preliminary antitumor activity of neratinib (HKI-272), an irreversible pan ErbB inhibitor, were determined in patients with advanced solid tumors. Neratinib was administered orally as a single dose, followed by a 1-week observation period, and then once daily continuously. Planned dose escalation was 40, 80, 120, 180, 240, 320, 400, and 500 mg. For pharmacokinetic analysis, timed blood samples were collected after administration of the single dose and after the first 14 days of continuous daily administration. Dose-limiting toxicity was grade 3 diarrhea, which occurred in one patient treated with 180 mg and in four patients treated with 400 mg neratinib; hence, the maximum tolerated dose was determined to be 320 mg. Other common neratinib-related toxicities included nausea, vomiting, fatigue, and anorexia. Exposure to neratinib was dose dependent, and the pharmacokinetic profile of neratinib supports a once-a-day dosing regimen. Partial response was observed for 8 (32%) of the 25 evaluable patients with breast cancer. Stable disease >or=24 weeks was observed in one evaluable breast cancer patient and 6 (43%) of the 14 evaluable non-small cell lung cancer patients. The maximum tolerated dose of once-daily oral neratinib is 320 mg. The most common neratinib-related toxicity was diarrhea. Antitumor activity was observed in patients with breast cancer who had previous treatment with trastuzumab, anthracyclines, and taxanes, and tumors with a baseline ErbB-2 immunohistochemical staining intensity of 2+ or 3+. The antitumor activity, tolerable toxicity profile, and pharmacokinetic properties of neratinib warrant its further evaluation.

Implementation of a dose gradient method into optimization of dose distribution in prostate cancer 3D-CRT plans

PubMed Central

Giżyńska, Marta K.; Kukołowicz, Paweł F.; Kordowski, Paweł

2014-01-01

Aim The aim of this work is to present a method of beam weight and wedge angle optimization for patients with prostate cancer. Background 3D-CRT is usually realized with forward planning based on a trial and error method. Several authors have published a few methods of beam weight optimization applicable to the 3D-CRT. Still, none on these methods is in common use. Materials and methods Optimization is based on the assumption that the best plan is achieved if dose gradient at ICRU point is equal to zero. Our optimization algorithm requires beam quality index, depth of maximum dose, profiles of wedged fields and maximum dose to femoral heads. The method was tested for 10 patients with prostate cancer, treated with the 3-field technique. Optimized plans were compared with plans prepared by 12 experienced planners. Dose standard deviation in target volume, and minimum and maximum doses were analyzed. Results The quality of plans obtained with the proposed optimization algorithms was comparable to that prepared by experienced planners. Mean difference in target dose standard deviation was 0.1% in favor of the plans prepared by planners for optimization of beam weights and wedge angles. Introducing a correction factor for patient body outline for dose gradient at ICRU point improved dose distribution homogeneity. On average, a 0.1% lower standard deviation was achieved with the optimization algorithm. No significant difference in mean dose–volume histogram for the rectum was observed. Conclusions Optimization shortens very much time planning. The average planning time was 5 min and less than a minute for forward and computer optimization, respectively. PMID:25337411

Factors Associated With Chest Wall Toxicity After Accelerated Partial Breast Irradiation Using High-Dose-Rate Brachytherapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Brown, Sheree, E-mail: shereedst32@hotmail.com; Vicini, Frank; Vanapalli, Jyotsna R.

2012-07-01

Purpose: The purpose of this analysis was to evaluate dose-volume relationships associated with a higher probability for developing chest wall toxicity (pain) after accelerated partial breast irradiation (APBI) by using both single-lumen and multilumen brachytherapy. Methods and Materials: Rib dose data were available for 89 patients treated with APBI and were correlated with the development of chest wall/rib pain at any point after treatment. Ribs were contoured on computed tomography planning scans, and rib dose-volume histograms (DVH) along with histograms for other structures were constructed. Rib DVH data for all patients were sampled at all volumes {>=}0.008 cubic centimeter (cc)more » (for maximum dose related to pain) and at volumes of 0.5, 1, 2, and 3 cc for analysis. Rib pain was evaluated at each follow-up visit. Patient responses were marked as yes or no. No attempt was made to grade responses. Eighty-nine responses were available for this analysis. Results: Nineteen patients (21.3%) complained of transient chest wall/rib pain at any point in follow-up. Analysis showed a direct correlation between total dose received and volume of rib irradiated with the probability of developing rib/chest wall pain at any point after follow-up. The median maximum dose at volumes {>=}0.008 cc of rib in patients who experienced chest wall pain was 132% of the prescribed dose versus 95% of the prescribed dose in those patients who did not experience pain (p = 0.0035). Conclusions: Although the incidence of chest wall/rib pain is quite low with APBI brachytherapy, attempts should be made to keep the volume of rib irradiated at a minimum and the maximum dose received by the chest wall as low as reasonably achievable.« less

Dependence of normal brain integral dose and normal tissue complication probability on the prescription isodose values for γ-knife radiosurgery

NASA Astrophysics Data System (ADS)

Ma, Lijun

2001-11-01

A recent multi-institutional clinical study suggested possible benefits of lowering the prescription isodose lines for stereotactic radiosurgery procedures. In this study, we investigate the dependence of the normal brain integral dose and the normal tissue complication probability (NTCP) on the prescription isodose values for γ-knife radiosurgery. An analytical dose model was developed for γ-knife treatment planning. The dose model was commissioned by fitting the measured dose profiles for each helmet size. The dose model was validated by comparing its results with the Leksell gamma plan (LGP, version 5.30) calculations. The normal brain integral dose and the NTCP were computed and analysed for an ensemble of treatment cases. The functional dependence of the normal brain integral dose and the NCTP versus the prescribing isodose values was studied for these cases. We found that the normal brain integral dose and the NTCP increase significantly when lowering the prescription isodose lines from 50% to 35% of the maximum tumour dose. Alternatively, the normal brain integral dose and the NTCP decrease significantly when raising the prescribing isodose lines from 50% to 65% of the maximum tumour dose. The results may be used as a guideline for designing future dose escalation studies for γ-knife applications.

Intravenous zoledronate for osteoporosis: less might be more

PubMed Central

Grey, Andrew

2016-01-01

Annual administration of 5 mg intravenous zoledronate is moderately effective in reducing fracture risk in older adults, decreasing the relative risk of clinical fracture by 33%. However, almost 10 years after its approval for use in clinical practice there remain very substantial uncertainties about the optimal treatment regimen, that is, the lowest dose and/or longest dosing interval that is efficacious. Several pieces of clinical research suggest that the current recommendation for annual administration of 5 mg zoledronate might represent overtreatment. Clinical trials to clarify the optimal use of zoledronate for reduction of fracture risk should be undertaken. PMID:27493690

Intravenous zoledronate for osteoporosis: less might be more.

PubMed

Grey, Andrew

2016-08-01

Annual administration of 5 mg intravenous zoledronate is moderately effective in reducing fracture risk in older adults, decreasing the relative risk of clinical fracture by 33%. However, almost 10 years after its approval for use in clinical practice there remain very substantial uncertainties about the optimal treatment regimen, that is, the lowest dose and/or longest dosing interval that is efficacious. Several pieces of clinical research suggest that the current recommendation for annual administration of 5 mg zoledronate might represent overtreatment. Clinical trials to clarify the optimal use of zoledronate for reduction of fracture risk should be undertaken.

SU-E-T-607: Performance Quantification of the Nine Detectors Used for Dosimetry Measurements in Advanced Radiation Therapy Treatments

DOE Office of Scientific and Technical Information (OSTI.GOV)

Markovic, M; Stathakis, S; Jurkovic, I

2015-06-15

Purpose: The purpose of this study was to quantify performance of the nine detectors used for dosimetry measurements in advanced radiation therapy treatments. Methods: The 6 MV beam was utilized for measurements of the field sizes with the lack of lateral charge particle equilibrium. For dose fidelity aspect, energy dependence was studied by measuring PDD and profiles at different depths. The volume effect and its influence on the measured dose profiles have been observed by measuring detector’s response function. Output factor measurements with respect to change in energy spectrum have been performed and collected data has been analyzed. The linearitymore » of the measurements with the dose delivered has been evaluated and relevant comparisons were done. Results: The measured values of the output factors with respect to change in energy spectrum indicated presence of the energy dependence. The detectors with active volume size ≤ 0.3 mm3 maximum deviation from the mean is 5.6% for the field size 0.5 x 0.5 cm2 while detectors with active volume size > 0.3 mm3 have maximum deviation from the mean 7.1%. Linearity with dose at highest dose rate examined for diode detectors showed maximum deviation of 4% while ion chambers showed maximum deviation of 2.2%. Dose profiles showed energy dependence at shallow depths (surface to dmax) influenced by low energy particles with 12 % maximum deviation from the mean for 5 mm2 field size. In relation to Monte Carlo calculation, the detector’s response function σ values were between (0.42±0.25) mm and (1.2±0.25) mm. Conclusion: All the detectors are appropriate for the dosimetry measurements in advanced radiation therapy treatments. The choice of the detectors has to be determined by the application and the scope of the measurements in respect to energy dependence and ability to accurately resolve dose profiles as well as to it’s intrinsic characteristics.« less

SU-F-T-117: A Pilot Study of Organ Dose Reconstruction for Wilms Tumor Patients Treated with Radiation Therapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Makkia, R; Pelletier, C; Jung, J

Purpose: To reconstruct major organ doses for the Wilms tumor pediatric patients treated with radiation therapy using pediatric computational phantoms, treatment planning system (TPS), and Monte Carlo (MC) dose calculation methods. Methods: A total of ten female and male pediatric patients (15–88 months old) were selected from the National Wilms Tumor Study cohort and ten pediatric computational phantoms corresponding to the patient’s height and weight were selected for the organ dose reconstruction. Treatment plans were reconstructed on the computational phantoms in a Pinnacle TPS (v9.10) referring to treatment records and exported into DICOM-RT files, which were then used to generatemore » the input files for XVMC MC code. The mean doses to major organs and the dose received by 50% of the heart were calculated and compared between TPS and MC calculations. The same calculations were conducted by replacing the computational human phantoms with a series of diagnostic patient CT images selected by matching the height and weight of the patients to validate the anatomical accuracy of the computational phantoms. Results: Dose to organs located within the treatment fields from the computational phantoms and the diagnostic patient CT images agreed within 2% for all cases for both TPS and MC calculations. The maximum difference of organ doses was 55.9 % (thyroid), but the absolute dose difference in this case was 0.33 Gy which was 0.96% of the prescription dose. The doses to ovaries and testes from MC in out-of-field provided more discrepancy (the maximum difference of 13.2% and 50.8%, respectively). The maximum difference of the 50% heart volume dose between the phantoms and the patient CT images was 40.0%. Conclusion: This study showed the pediatric computational phantoms are applicable to organ doses reconstruction for the radiotherapy patients whose three-dimensional radiological images are not available.« less

Direct plan comparison of RapidArc and CyberKnife for spine stereotactic body radiation therapy

NASA Astrophysics Data System (ADS)

Choi, Young Eun; Kwak, Jungwon; Song, Si Yeol; Choi, Eun Kyung; Ahn, Seung Do; Cho, Byungchul

2015-07-01

We compared the treatment planning performance of RapidArc (RA) vs. CyberKnife (CK) for spinal stereotactic body radiation therapy (SBRT). Ten patients with spinal lesions who had been treated with CK were re-planned with RA, which consisted of two complete arcs. Computed tomography (CT) and volumetric dose data of CK, generated using the Multiplan (Accuray) treatment planning system (TPS) and the Ray-trace algorithm, were imported to Varian Eclipse TPS in Dicom format, and the data were compared with the RA plan by using an analytical anisotropic algorithm (AAA) dose calculation. The optimized dose priorities for both the CK and the RA plans were similar for all patients. The highest priority was to provide enough dose coverage to the planned target volume (PTV) while limiting the maximum dose to the spinal cord. Plan quality was evaluated with respect to PTV coverage, conformity index (CI), high-dose spillage, intermediate-dose spillage (R50% and D2cm), and maximum dose to the spinal cord, which are criteria recommended by the RTOG 0631 spine and 0915 lung SBRT protocols. The mean CI' SD values of the PTV were 1.11' 0.03 and 1.17' 0.10 for RA and CK ( p = 0.02), respectively. On average, the maximum dose delivered to the spinal cord in CK plans was approximately 11.6% higher than that in RA plans, and this difference was statistically significant ( p < 0.001). High-dose spillages were 0.86% and 2.26% for RA and CK ( p = 0.203), respectively. Intermediate-dose spillage characterized by D2cm was lower for RA than for CK; however, R50% was not statistically different. Even though both systems can create highly conformal volumetric dose distributions, the current study shows that RA demonstrates lower high- and intermediate-dose spillages than CK. Therefore, RA plans for spinal SBRT may be superior to CK plans.

FLO1K, global maps of mean, maximum and minimum annual streamflow at 1 km resolution from 1960 through 2015

NASA Astrophysics Data System (ADS)

Barbarossa, Valerio; Huijbregts, Mark A. J.; Beusen, Arthur H. W.; Beck, Hylke E.; King, Henry; Schipper, Aafke M.

2018-03-01

Streamflow data is highly relevant for a variety of socio-economic as well as ecological analyses or applications, but a high-resolution global streamflow dataset is yet lacking. We created FLO1K, a consistent streamflow dataset at a resolution of 30 arc seconds (~1 km) and global coverage. FLO1K comprises mean, maximum and minimum annual flow for each year in the period 1960-2015, provided as spatially continuous gridded layers. We mapped streamflow by means of artificial neural networks (ANNs) regression. An ensemble of ANNs were fitted on monthly streamflow observations from 6600 monitoring stations worldwide, i.e., minimum and maximum annual flows represent the lowest and highest mean monthly flows for a given year. As covariates we used the upstream-catchment physiography (area, surface slope, elevation) and year-specific climatic variables (precipitation, temperature, potential evapotranspiration, aridity index and seasonality indices). Confronting the maps with independent data indicated good agreement (R2 values up to 91%). FLO1K delivers essential data for freshwater ecology and water resources analyses at a global scale and yet high spatial resolution.

Estimating distribution parameters of annual maximum streamflows in Johor, Malaysia using TL-moments approach

NASA Astrophysics Data System (ADS)

Mat Jan, Nur Amalina; Shabri, Ani

2017-01-01

TL-moments approach has been used in an analysis to identify the best-fitting distributions to represent the annual series of maximum streamflow data over seven stations in Johor, Malaysia. The TL-moments with different trimming values are used to estimate the parameter of the selected distributions namely: Three-parameter lognormal (LN3) and Pearson Type III (P3) distribution. The main objective of this study is to derive the TL-moments ( t 1,0), t 1 = 1,2,3,4 methods for LN3 and P3 distributions. The performance of TL-moments ( t 1,0), t 1 = 1,2,3,4 was compared with L-moments through Monte Carlo simulation and streamflow data over a station in Johor, Malaysia. The absolute error is used to test the influence of TL-moments methods on estimated probability distribution functions. From the cases in this study, the results show that TL-moments with four trimmed smallest values from the conceptual sample (TL-moments [4, 0]) of LN3 distribution was the most appropriate in most of the stations of the annual maximum streamflow series in Johor, Malaysia.

A Closer Look at the Congo and the Lightning Maximum on Earth

NASA Technical Reports Server (NTRS)

Blakeslee, R. J.; Buechler, D. E.; Lavreau, Johan; Goodman, Steven J.

2008-01-01

The global maps of maximum mean annual flash density derived from a decade of observations from the Lightning Imaging Sensor on the NASA Tropical Rainfall Measuring Mission (TRMM) satellite show that a 0.5 degree x 0.5 degree pixel west of Bukavu, Democratic Republic of Congo (latitude 2S, longitude 28E) has the most frequent lightning activity anywhere on earth with an average value in excess of 157 fl/sq km/yr. This pixel has a flash density that is much greater than even its surrounding neighbors. By contrast the maximum mean annual flash rate for North America located in central Florida is only 33 fl/sq km/yr. Previous studies have shown that monthly-seasonal-annual lightning maxima on earth occur in regions dominated by coastal (land-sea breeze interactions) or topographic influences (elevated heat sources, enhanced convergence). Using TRMM, Landsat Enhanced Thematic Mapper, and Shuttle Imaging Radar imagery we further examine the unique features of this region situated in the deep tropics and dominated by a complex topography having numerous mountain ridges and valleys to better understand why this pixel, unlike any other, has the most active lightning on the planet.

Radiological maps for Trabzon, Turkey.

PubMed

Kurnaz, A; Kucukomeroglu, B; Damla, N; Cevik, U

2011-04-01

The activity concentrations and absorbed gamma dose rates due to primordial radionuclides and (137)Cs have been ascertained in 222 soil samples in 18 counties of the Trabzon province of Turkey using a HPGe detector. The mean activity concentrations of (238)U, (232)Th, (40)K and (137)Cs in soil samples were 41, 35, 437 and 21 Bq kg(-1), respectively. Based on the measured concentrations of these radionuclides, the mean absorbed gamma dose in air was calculated as 59 nGy h(-1) and hence, the mean annual effective dose due to terrestrial gamma radiation was calculated as 72 μSv y(-1). In addition, outdoor in situ gamma dose rate (D) measurements were performed in the same 222 locations using a portable NaI detector and the annual effective dose was calculated to be 66 μSv y(-1) from these results. The results presented in this study are compared with other parts of Turkey. Radiological maps of the Trabzon province were composed using the results obtained from the study. Copyright © 2011 Elsevier Ltd. All rights reserved.

²¹⁰Po in the diet at Seville (Spain) and its contribution to the dose by ingestion.

PubMed

Díaz-Francés, I; Mantero, J; Díaz-Ruiz, J; Manjón, G; García-Tenorio, R

2016-02-01

The activity concentrations of (210)Po have been determined in a total of 24 representative diet samples from Seville (south of Spain), inferring from the obtained values the annual intakes of (210)Po by ingestion of the affected population and the corresponding committed effective doses. The annual intakes of (210)Po and, consequently, the corresponding doses of this radionuclide show a high variability in correspondence with the variability in the composition of the analysed samples over time, and their magnitude is comparable with the estimated ones in other regions/countries of the world with similar diet habits (countries where the marine products have a considerable weight in the diets). Committed effective doses by ingestion higher than 0.1 mSv y(-1) have been estimated exclusively for (210)Po, reflecting the importance of this radionuclide and this route of incorporation in the magnitude of the total doses received by the affected population from natural sources. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Radioactivity concentrations in soils in the Qingdao area, China.

PubMed

Qu, Limei; Yao, De; Cong, Pifu; Xia, Ning

2008-10-01

The specific activity concentrations of radionuclides (238)U, (232)Th, and (40)K of 2300 sampling points in the Qingdao area were measured by an FD-3022 gamma-ray spectrometer. The radioactivity concentrations of (238)U, (232)Th, and (40)K ranged from 3.3 to 185.3, from 6.9 to 157.2, and from 115.8 to 7834.4 Bq kg(-1), respectively. The air-absorbed dose at 1 meter above ground, effective annual dose, external hazard index, and radium equivalent activity were also calculated to systematically evaluate the radiological hazards of the natural radioactivity in Qingdao. The air-absorbed dose, effective annual dose, external hazard index, and radium equivalent activity in the study area were 98.6 nGy h(-1), 0.12 mSv, 0.56, 197 Bq kg(-1), respectively. Compared with the worldwide value, the air-absorbed dose is slightly high, but the other factors are all lower than the recommended value. The natural external exposure will not pose significant radiological threat to the population. In conclusion, the Qingdao area is safe with regard to the radiological level and suitable for living.

Environmental consequences of postulated plutonium releases from General Electric Company Vallecitos Nuclear Center, Vallecitos, California, as a result of severe natural phenomena

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jamison, J.D.; Watson, E.C.

1980-11-01

Potential environmental consequences in terms of radiation dose to people are presented for postulated plutonium releases caused by severe natural phenomena at the General Electric Company Vallecitos Nuclear Center, Vallecitos, California. The severe natural phenomena considered are earthquakes, tornadoes, and high straight-line winds. Maximum plutonium deposition values are given for significant locations around the site. All important potential exposure pathways are examined. The most likely 50-year committed dose equivalents are given for the maximum-exposed individual and the population within a 50-mile radius of the plant. The maximum plutonium deposition values likely to occur offsite are also given. The most likelymore » calculated 50-year collective committed dose equivalents are all much lower than the collective dose equivalent expected from 50 years of exposure to natural background radiation and medical x-rays. The most likely maximum residual plutonium contamination estimated to be deposited offsite following the earthquakes, and the 180-mph and 230-mph tornadoes are above the Environmental Protection Agency's (EPA) proposed guideline for plutonium in the general environment of 0.2 ..mu..Ci/m/sup 2/. The deposition values following the 135-mph tornado are below the EPA proposed guidelines.« less

Factors driving spatial and temporal variation in production and production/biomass ratio of stream-resident brown trout (Salmo trutta) in Cantabrian streams

USGS Publications Warehouse

Lobon-Cervia, J.; Gonzalez, G.; Budy, P.

2011-01-01

1.The objective was to identify the factors driving spatial and temporal variation in annual production (PA) and turnover (production/biomass) ratio (P/BA) of resident brown trout Salmo trutta in tributaries of the Rio Esva (Cantabrian Mountains, Asturias, north-western Spain). We examined annual production (total production of all age-classes over a year) (PA) and turnover (P/BA) ratios, in relation to year-class production (production over the entire life time of a year-class) (PT) and turnover (P/BT) ratio, over 14years at a total of 12 sites along the length of four contrasting tributaries. In addition, we explored whether the importance of recruitment and site depth for spatial and temporal variations in year-class production (PT), elucidated in previous studies, extends to annual production. 2.Large spatial (among sites) and temporal (among years) variation in annual production (range 1.9-40.3gm-2 per year) and P/BA ratio (range 0.76-2.4per year) typified these populations, values reported here including all the variation reported globally for salmonids streams inhabited by one or several species. 3.Despite substantial differences among streams and sites in all production attributes, when all data were pooled, annual (PA) and year-class production (PT) and annual (P/BA) and year-class P/BT ratios were tightly linked. Annual (PA) and year-class production (PT) were similar but not identical, i.e. PT=0.94 PA, whereas the P/BT ratios were 4+P/BA ratios. 4.Recruitment (Rc) and mean annual density (NA) were major density-dependent drivers of production and their relationships were described by simple mathematical models. While year-class production (PT) was determined (R2=70.1%) by recruitment (Rc), annual production (PA) was determined (R2=60.3%) by mean annual density (NA). In turn, variation in recruitment explained R2=55.2% of variation in year-class P/BT ratios, the latter attaining an asymptote at P/BT=6 at progressively higher levels of recruitment. Similarly, variations in mean annual density (NA) explained R2=52.1% of variation in annual P/BA, the latter reaching an asymptote at P/BA=2.1. This explained why P/BT is equal to P/BA plus the number of year-classes at high but not at low densities. 5.Site depth was a major determinant of spatial (among sites) variation in production attributes. All these attributes described two-phase trajectories with site depth, reaching a maximum at sites of intermediate depth and declining at shallower and deeper sites. As a consequence, at sites where recruitment and mean annual density reached minimum or maximum values, annual (PA) and year-class production (PT) and annual (P/BA) and year-class P/BT ratios also reached minimum and maximum values. ?? 2011 Blackwell Publishing Ltd.

How Should Dry Lightning be Defined to Best to Correlate to Wildfire Initiation?

NASA Astrophysics Data System (ADS)

Vant-Hull, B.; Koshak, W. J.

2017-12-01

Dry lightning can be defined by a maximum precipitation threshold, a dry period preceding a flash, and the spatial resolution used to relate a lightning flash to precipitation. Using data from most of CONUS from 2003-2015, the annual total of wildfires was compared to the annual number of dry flashes, with dry flash parameters adjusted to maximize the correlation between annual totals throughout the time period. A maximum correlation of 0.93 was found for a dry period of 36 hours, with no precipitation rates above 0.2 mm/hr during this time, on a 0.1 degree grid. Such a high correlation to wildfires on a climatic scale indicates a need to understand how changing weather patterns can influence the occurrence of properly defined dry lightning. Under this understanding dry lightning counts could qualify as a NCA indicator.

Analytical expressions for maximum wind turbine average power in a Rayleigh wind regime

DOE Office of Scientific and Technical Information (OSTI.GOV)

Carlin, P.W.

Average or expectation values for annual power of a wind turbine in a Rayleigh wind regime are calculated and plotted as a function of cut-out wind speed. This wind speed is expressed in multiples of the annual average wind speed at the turbine installation site. To provide a common basis for comparison of all real and imagined turbines, the Rayleigh-Betz wind machine is postulated. This machine is an ideal wind machine operating with the ideal Betz power coefficient of 0.593 in a Rayleigh probability wind regime. All other average annual powers are expressed in fractions of that power. Cases consideredmore » include: (1) an ideal machine with finite power and finite cutout speed, (2) real machines operating in variable speed mode at their maximum power coefficient, and (3) real machines operating at constant speed.« less

Feasibility of Administering High-Dose 131I-MIBG Therapy to Children with High-Risk Neuroblastoma without Lead-Lined Rooms

PubMed Central

Chu, Bae P.; Horan, Christopher; Basu, Ellen; Dauer, Lawrence; Williamson, Matthew; Carrasquillo, Jorge A.; Pandit-Taskar, Neeta; Modak, Shakeel

2015-01-01

Background Although 131I-metaiodobenzylguanidine therapy (131I-MIBG) is increasingly used for children with high-risk neuroblastoma, a paucity of lead-lined rooms limits its wider use. We implemented radiation safety procedures to comply with New York City Department of Health and Mental Hygiene regulations for therapeutic radioisotopes and administered 131I-MIBG using rolling lead shields. Procedure Patients received 0.67GBq (18mCi)/kg/dose 131I-MIBG on an IRB-approved protocol (NCT00107289). Radiation safety procedures included private room with installation of rolling lead shields to maintain area dose rates ≤0.02mSv/h outside the room, patient isolation until dose rate <0.07mSv/h at 1m and retention of a urinary catheter with collection of urine in lead boxes. Parents were permitted in the patient’s room behind lead shields, trained in radiation safety principles and given real-time radiation monitors. Results Records on 16 131I-MIBG infusions among 10 patients (age 2–11 years) were reviewed. Mean ± standard deviation 131I-MIBG administered was 17.67±11.14 (range: 6.11–40.59) GBq. Mean maximum dose rates outside treatment rooms were 0.013±0.008 mSv/hr. Median time-to-discharge was 3 days post-131I-MIBG. Exposure of medical staff and parents was below regulatory limits. Cumulative whole-body dose received by the physician, nurse and radiation safety officer during treatment was 0.098±0.058, 0.056±0.045, 0.055±0.050 mSv respectively. Cumulative exposure to parents was 0.978±0.579mSv. Estimated annual radiation exposure for inpatient nurses was 0.096±0.034mSv/nurse. Thyroid bioassay scans on all medical personnel were

Modeled future peak streamflows in four coastal Maine rivers

USGS Publications Warehouse

Hodgkins, Glenn A.; Dudley, Robert W.

2013-01-01

To safely and economically design bridges and culverts, it is necessary to compute the magnitude of peak streamflows that have specified annual exceedance probabilities (AEPs). Annual precipitation and air temperature in the northeastern United States are, in general, projected to increase during the 21st century. It is therefore important for engineers and resource managers to understand how peak flows may change in the future. This report, prepared in cooperation with the Maine Department of Transportation (MaineDOT), presents modeled changes in peak flows at four basins in coastal Maine on the basis of projected changes in air temperature and precipitation. To estimate future peak streamflows at the four basins in this study, historical values for climate (temperature and precipitation) in the basins were adjusted by different amounts and input to a hydrologic model of each study basin. To encompass the projected changes in climate in coastal Maine by the end of the 21st century, air temperatures were adjusted by four different amounts, from -3.6 degrees Fahrenheit (ºF) (-2 degrees Celsius (ºC)) to +10.8 ºF (+6 ºC) of observed temperatures. Precipitation was adjusted by three different percentage values from -15 percent to +30 percent of observed precipitation. The resulting 20 combinations of temperature and precipitation changes (includes the no-change scenarios) were input to Precipitation-Runoff Modeling System (PRMS) watershed models, and annual daily maximum peak flows were calculated for each combination. Modeled peak flows from the adjusted changes in temperature and precipitation were compared to unadjusted (historical) modeled peak flows. Annual daily maximum peak flows increase or decrease, depending on whether temperature or precipitation is adjusted; increases in air temperature (with no change in precipitation) lead to decreases in peak flows, whereas increases in precipitation (with no change in temperature) lead to increases in peak flows. As the magnitude of air temperatures increase in the four basins, peak flows decrease by larger amounts. If precipitation is held constant (no change from historical values), 17 to 26 percent decreases in peak flow occur at the four basins when temperature is increased by 7.2°F. If temperature is held constant, 26 to 38 percent increases in peak flow result from a 15-percent increase in precipitation. The largest decreases in peak flows at the four basins result from 15-percent decreases in precipitation combined with temperature increases of 10.8°F. The largest increases in peak flows generally result from 30-percent increases in precipitation combined with 3.6 °F decreases in temperatures. In many cases when temperature and precipitation both increase, small increases or decreases in annual daily maximum peak flows result. For likely changes projected for the northeastern United States for the middle of the 21st century (temperature increase of 3.6 °F and precipitation increases of 0 to 15 percent), peak-flow changes at the four coastal Maine basins in this study are modeled to be evenly distributed between increases and decreases of less than 25 percent. Peak flows with 50-percent and 1-percent AEPs (equivalent to 2-year and 100-year recurrence interval peak flows, respectively) were calculated for the four basins in the study using the PRMS-modeled annual daily maximum peak flows. Modeled peak flows with 50-percent and 1-percent AEPs with adjusted temperatures and precipitation were compared to unadjusted (historical) modeled values. Changes in peak flows with 50-percent AEPs are similar to changes in annual daily maximum peak flow; changes in peak flows with 1-percent AEPs are similar in pattern to changes in annual daily maximum peak flow, but some of the changes associated with increasing precipitation are much larger than changes in annual daily maximum peak flow. Substantial decreases in maximum annual winter snowpack water equivalent are modeled to occur with increasing air temperatures at the four basins in the study. (Snowpack is the snow on the ground that accumulates during a winter, and water equivalent is the amount of water in a snowpack if it were melted.) The decrease in modeled peak flows with increasing air temperature, given no change in precipitation amount, is likely caused by these decreases in winter snowpack and resulting decreases in snowmelt runoff. This Scientific Investigations Report, prepared in cooperation with the Maine Department of Transportation, presents a summary of modeled changes in peak flows at four basins in coastal Maine on the basis of projected changes in air temperature and precipitation. The full Fact Sheet (Hodgkins and Dudley, 2013) is available at http://pubs.usgs.gov/fs/2013/3021/.

77 FR 73005 - Fisheries Off West Coast States; Coastal Pelagic Species Fisheries; Annual Specifications

Federal Register 2010, 2011, 2012, 2013, 2014

2012-12-07

... (NOAA), Commerce. ACTION: Proposed rule. SUMMARY: NMFS proposes to implement the annual catch limit (ACL...) Fishery Management Plan (FMP). The proposed 2012-2013 ACL or maximum HG for Pacific mackerel is 40,514... the fishery attains the ACT, the directed fishery will close, reserving the difference between the ACL...

Flood frequency analysis for a braided river catchment in New Zealand: Comparing annual maximum and partial duration series with varying record lengths

NASA Astrophysics Data System (ADS)

Nagy, B. K.; Mohssen, M.; Hughey, K. F. D.

2017-04-01

This study addresses technical questions concerning the use of the partial duration series (PDS) within the domain of flood frequency analysis. The recurring questions which often prevent the standardised use of the PDS are peak independence and threshold selection. This paper explores standardised approaches to peak and threshold selection to produce PDS samples with differing average annual exceedances, using six theoretical probability distributions. The availability of historical annual maximum (AMS) data (1930-1966) in addition to systemic AMS data (1967-2015) enables a unique comparison between the performance of the PDS sample and the systemic AMS sample. A recently derived formula for the translation of the PDS into the annual domain, simplifying the use of the PDS, is utilised in an applied case study for the first time. Overall, the study shows that PDS sampling returns flood magnitudes similar to those produced by AMS series utilising historical data and thus the use of the PDS should be preferred in cases where historical flood data is unavailable.

Hydrologic effects of annually diverting 131,000 acre-feet of water from Dillon Reservoir, central Colorado

USGS Publications Warehouse

Alley, William M.; Bauer, D.P.; Veenhuis, J.E.; Brennan, Robert

1979-01-01

Because of the increased demands for water in eastern Colorado, principally in the urbanizing Denver metropolitan area, increased diversions of water from Dillon Reservoir are planned. Estimates of end-of-month storage in Dillon Reservoir, assuming the reservoir was in place and 131,000 acre-feet of water were diverted from the reservoir each year, were reconstructed by mass balance for the 1931-77 water years. Based on the analysis, the annual maximum end-of-month drawdown below the elevation at full storage would have averaged 54 feet. The maximum end-of-month drawdown below the elevation at full storage would have been 171 feet. The mean-annual discharge-weighted dissolved-solids concentrations in the Colorado River near Glenwood Springs and Cameo, Colo., and Cisco, Utah, for the 1942-77 water years, were computed assuming an annual diversion of 131,000 acre-feet of water from Dillon Reservoir. The average increases in the dissolved-solids concentrations with the 131 ,000-acre-foot diversion were 15 to 16 milligrams per liter at the three sites. (Woodard-USGS)

50 CFR 679.81 - Rockfish Program annual harvester privileges.

Code of Federal Regulations, 2012 CFR

2012-10-01

...) Maximum retainable amount (MRA) limits—(1) Rockfish cooperative. A vessel assigned to a rockfish... those species as established in Table 10 to this part. (4) Maximum retainable amount (MRA) calculation and limits—catcher vessels. (i) The MRA for an incidental catch species for vessels fishing under the...

50 CFR 679.81 - Rockfish Program annual harvester privileges.

Code of Federal Regulations, 2013 CFR

2013-10-01

...) Maximum retainable amount (MRA) limits—(1) Rockfish cooperative. A vessel assigned to a rockfish... those species as established in Table 10 to this part. (4) Maximum retainable amount (MRA) calculation and limits—catcher vessels. (i) The MRA for an incidental catch species for vessels fishing under the...

50 CFR 679.81 - Rockfish Program annual harvester privileges.

Code of Federal Regulations, 2014 CFR

2014-10-01

...) Maximum retainable amount (MRA) limits—(1) Rockfish cooperative. A vessel assigned to a rockfish... those species as established in Table 10 to this part. (4) Maximum retainable amount (MRA) calculation and limits—catcher vessels. (i) The MRA for an incidental catch species for vessels fishing under the...

24 CFR 882.403 - ACC, housing assistance payments contract, and lease.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 24 Housing and Urban Development 4 2011-04-01 2011-04-01 false ACC, housing assistance payments... Procedures for Moderate Rehabilitation-Basic Policies § 882.403 ACC, housing assistance payments contract, and lease. (a) Maximum Total ACC Commitments. The maximum total annual contribution that may be...

Effects of Wildfire on the Hydrology of Capulin and Rito de los Frijoles canyons, Bandelier National Monument, New Mexico

USGS Publications Warehouse

Veenhuis, Jack E.

2002-01-01

In June of 1977, the La Mesa wildfire burned 15,270 acres in and around Frijoles Canyon in Bandelier National Monument and the adjacent Santa Fe National Forest, New Mexico. The Dome wildfire in April of 1996 in Bandelier National Monument burned 16,516 acres in Capulin Canyon and the surrounding Dome Wilderness area. Both watersheds are characterized by abundant and extensive archeological sites that could be affected by increased runoff and accelerated rates of erosion, which typically occur after a wildfire. The U.S. Geological Survey in cooperation with the National Park Service monitored the wildfires' effects on streamflow in both canyons. The magnitude of large stormflows increased dramatically after these wildfires; peak flows at the most downstream streamflow-gaging station in Frijoles and Capulin Canyons increased to about 160 times the maximum recorded flood prior to the fire. Maximum peak flow was 3,030 cubic feet per second at the gaging station in Frijoles Canyon (drainage area equals 18.1 square miles) and 3,630 cubic feet per second at the most downstream crest-stage gage in Capulin Canyon (drainage area equals 14.1 square miles). The pre-fire maximum peak flow recorded in these two canyons was 19 and an estimated 25 cubic feet per second, respectively. As vegetation reestablished itself during the second year, the post-fire annual maximum peak flow decreased to about 10 to 15 times the pre-fire annual maximum peak flow. During the third year, maximum annual peak flows decreased to about three to five times the pre-fire maximum peak flow. In the 22 years since the La Mesa wildfire, flood magnitudes have not completely returned to pre-fire size. Post-fire flood magnitudes in Frijoles and Capulin Canyons do not exceed the maximum floods per drainage area for physiographic regions 5 and 6 in New Mexico. For a burned watershed, however, the peak flows that occur after a wildfire are several orders of magnitude larger than normal forested watershed peak flows. The frequency of larger stormflows also increased in response to the effects of the wildfires in both canyons. In Frijoles Canyon, the number of peak stormflows greater than the pre-fire maximum flow of 19 cubic feet per second was 15 in 1977, 9 in 1978, and 5 in 1979, which is about the magnitude of the maximum pre-fire peak flow in both canyons. Again the hydrologic effects of a wildfire seem to be more pronounced for the 3 years following the date of the fire. Likewise, larger peakflows occurred more frequently in Capulin Canyon for the first 3 years after the 1996 wildfire. Median suspended-sediment concentrations in samples collected in Frijoles Canyon in 1977 were 1,330 milligrams per liter; median concentrations were 16 milligrams per liter after the watershed stabilized in 1993-95. The annual load calculated from regression equations for load compared to flow for the first year after the wildfire was 220 times the annual load for the post-recovery period. To convey the increased frequency and magnitude of average flows in Capulin Canyon after the 1996 Dome wildfire, the stream channel in Capulin Canyon increased in flow capacity by widening and downcutting. As Capulin Canyon peak flows have decreased in both magnitude and frequency with vegetative recovery, the stream channel also has slowly begun to readjust. The channel at the most downstream crest-stage gage, which has the shallowest initial valley slope, is showing the first signs of aggradation.

Measurement of the natural radioactivity in building materials used in Ankara and assessment of external doses.

PubMed

Turhan, S; Baykan, U N; Sen, K

2008-03-01

A total of 183 samples of 20 different commonly used structural and covering building materials were collected from housing and other building construction sites and from suppliers in Ankara to measure the natural radioactivity due to the presence of (226)Ra, (232)Th and (40)K. The measurements were carried out using gamma-ray spectrometry with two HPGe detectors. The specific activities of the different building materials studied varied from 0.5 +/- 0.1 to 144.9 +/- 4.9 Bq kg(-1), 0.6 +/- 0.2 to 169.9 +/- 6.6 Bq kg(-1) and 2.0 +/- 0.1 to 1792.3 +/- 60.8 Bq kg(-1) for (226)Ra, (232)Th and (40)K, respectively. The results show that the lowest mean values of the specific activity of (226)Ra, (232)Th and (40)K are 0.8 +/- 0.5, 0.9 +/- 0.4 and 4.1 +/- 1.4 Bq kg(-1), respectively, measured in travertine tile while the highest mean values of the specific activity of the same radionuclides are 78.5 +/- 18.1 (ceramic wall tile), 77.4 +/- 53.0 (granite tile) and 923.4 +/- 161.0 (white brick), respectively. The radium equivalent activity (Ra(eq)), the gamma-index, the indoor absorbed dose rate and the corresponding annual effective dose were evaluated to assess the potential radiological hazard associated with these building materials. The mean values of the gamma-index and the estimated annual effective dose due to external gamma radiation inside the room for structural building materials ranged from 0.15 to 0.89 and 0.2 to 1.1 mSv, respectively. Applying criteria recently recommended for building materials in the literature, four materials meet the exemption annual dose criterion of 0.3 mSv, five materials meet the annual dose limit of 1 mSv and only one material slightly exceeds this limit. The mean values of the gamma-index for all building materials were lower than the upper limit of 1.

Low-dose glyphosate does not control annual bromes in the northern Great Plains

USDA-ARS?s Scientific Manuscript database

Annual bromes (downy brome and Japanese brome) have been shown to decrease perennial grass forage production and alter ecosystem functions in northern Great Plains rangelands. Large-scale chemical control might be a method for increasing rangeland forage production if low application rates confer co...

SU-E-T-493: Analysis of the Impact of Range and Setup Uncertainties On the Dose to Brain Stem and Whole Brain in the Passively Scattered Proton Therapy Plans

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sahoo, N; Zhu, X; Zhang, X

Purpose: To quantify the impact of range and setup uncertainties on various dosimetric indices that are used to assess normal tissue toxicities of patients receiving passive scattering proton beam therapy (PSPBT). Methods: Robust analysis of sample treatment plans of six brain cancer patients treated with PSPBT at our facility for whom the maximum brain stem dose exceeded 5800 CcGE were performed. The DVH of each plan was calculated in an Eclipse treatment planning system (TPS) version 11 applying ±3.5% range uncertainty and ±3 mm shift of the isocenter in x, y and z directions to account for setup uncertainties. Worst-casemore » dose indices for brain stem and whole brain were compared to their values in the nominal plan to determine the average change in their values. For the brain stem, maximum dose to 1 cc of volume, dose to 10%, 50%, 90% of volume (D10, D50, D90) and volume receiving 6000, 5400, 5000, 4500, 4000 CcGE (V60, V54, V50, V45, V40) were evaluated. For the whole brain, maximum dose to 1 cc of volume, and volume receiving 5400, 5000, 4500, 4000, 3000 CcGE (V54, V50, V45, V40 and V30) were assessed. Results: The average change in the values of these indices in the worst scenario cases from the nominal plan were as follows. Brain stem; Maximum dose to 1 cc of volume: 1.1%, D10: 1.4%, D50: 8.0%, D90:73.3%, V60:116.9%, V54:27.7%, V50: 21.2%, V45:16.2%, V40:13.6%,Whole brain; Maximum dose to 1 cc of volume: 0.3%, V54:11.4%, V50: 13.0%, V45:13.6%, V40:14.1%, V30:13.5%. Conclusion: Large to modest changes in the dosiemtric indices for brain stem and whole brain compared to nominal plan due to range and set up uncertainties were observed. Such potential changes should be taken into account while using any dosimetric parameters for outcome evaluation of patients receiving proton therapy.« less

Hydroclimate temporal variability in a coastal Mediterranean watershed: the Tafna basin, North-West Algeria

NASA Astrophysics Data System (ADS)

Boulariah, Ouafik; Longobardi, Antonia; Meddi, Mohamed

2017-04-01

One of the major challenges scientists, practitioners and stakeholders are nowadays involved in, is to provide the worldwide population with reliable water supplies, protecting, at the same time, the freshwater ecosystems quality and quantity. Climate and land use changes undermine the balance between water demand and water availability, causing alteration of rivers flow regime. Knowledge of hydro-climate variables temporal and spatial variability is clearly helpful to plan drought and flood hazard mitigation strategies but also to adapt them to future environmental scenarios. The present study relates to the coastal semi-arid Tafna catchment, located in the North-West of Algeria, within the Mediterranean basin. The aim is the investigation of streamflow and rainfall indices temporal variability in six sub-basins of the large catchment Tafna, attempting to relate streamflow and rainfall changes. Rainfall and streamflow time series have been preliminary tested for data quality and homogeneity, through the coupled application of two-tailed t test, Pettitt test and Cumsum tests (significance level of 0.1, 0.05 and 0.01). Subsequently maximum annual daily rainfall and streamflow and average daily annual rainfall and streamflow time series have been derived and tested for temporal variability, through the application of the Mann Kendall and Sen's test. Overall maximum annual daily streamflow time series exhibit a negative trend which is however significant for only 30% of the station. Maximum annual daily rainfall also e exhibit a negative trend which is intend significant for the 80% of the stations. In the case of average daily annual streamflow and rainfall, the tendency for decrease in time is unclear and, in both cases, appear significant for 60% of stations.

Dose received by occupationally exposed workers at a nuclear medicine department

NASA Astrophysics Data System (ADS)

Ávila, O.; Sánchez-Uribe, N. A.; Rodríguez-Laguna, A.; Medina, L. A.; Estrada, E.; Buenfil, A. E.; Brandan, M. E.

2012-10-01

Personal Dose Equivalent (PDE) values were determined for occupational exposed workers (OEW) at the Nuclear Medicine Department (NMD) of "Instituto Nacional de Cancerología" (INCan), Mexico, using TLD-100 thermoluminescent dosemeters. OEW at NMD, INCan make use of radiopharmaceuticals for diagnosis and treatment of diseases. Radionuclides associated to a pharmaceutical compound used at this Department are 131I, 18F, 68Ga, 99mTc, 111In and 11C with main gamma emission energies between 140 and 511 keV. Dosemeter calibration was performed at the metrology department of "Instituto Nacional de Investigaciones Nucleares" (ININ), Mexico. Every occupational worker used dark containers with three dosimeters which were replaced monthly for a total of 5 periods. Additionally, control dosemeters were also placed at a site free of radioactive sources in order to determine the background radiation. Results were adjusted to find PDE/day and estimating annual PDE values in the range between 2 mSv (background) and 9 mSv. The mean annual value is 3.51 mSv and the standard deviation SD is 0.78 mSv. Four of the 16 OEW received annual doses higher than the average +1 SD (4.29 mSv). Results depend on OEW daily activities and were consistent for each OEW for the 5 studied periods as well as with PDE values reported by the firm that performs the monthly service. All obtained values are well within the established annual OEW dose limit stated in the "Reglamento General de Seguridad Radiológica", México (50 mSv), as well as within the lower limit recommended by the "International Commission on Radiation Protection" (ICRP), report no.60 (20 mSv). These results verify the adequate compliance of the NMD at INCan, Mexico with the norms given by the national regulatory commission.

Exponentially increasing incidences of cutaneous malignant melanoma in Europe correlate with low personal annual UV doses and suggests 2 major risk factors

PubMed Central

Merrill, Stephen J; Ashrafi, Samira; Subramanian, Madhan; Godar, Dianne E

2015-01-01

For several decades the incidence of cutaneous malignant melanoma (CMM) steadily increased in fair-skinned, indoor-working people around the world. Scientists think poor tanning ability resulting in sunburns initiate CMM, but they do not understand why the incidence continues to increase despite the increased use of sunscreens and formulations offering more protection. This paradox, along with lower incidences of CMM in outdoor workers, although they have significantly higher annual UV doses than indoor workers have, perplexes scientists. We found a temporal exponential increase in the CMM incidence indicating second-order reaction kinetics revealing the existence of 2 major risk factors. From epidemiology studies, we know one major risk factor for getting CMM is poor tanning ability and we now propose the other major risk factor may be the Human Papilloma Virus (HPV) because clinicians find β HPVs in over half the biopsies. Moreover, we uncovered yet another paradox; the increasing CMM incidences significantly correlate with decreasing personal annual UV dose, a proxy for low vitamin D3 levels. We also discovered the incidence of CMM significantly increased with decreasing personal annual UV dose from 1960, when it was almost insignificant, to 2000. UV and other DNA-damaging agents can activate viruses, and UV-induced cytokines can hide HPV from immune surveillance, which may explain why CMM also occurs in anatomical locations where the sun does not shine. Thus, we propose the 2 major risk factors for getting CMM are intermittent UV exposures that result in low cutaneous levels of vitamin D3 and possibly viral infection. PMID:26413188

Hazelwood Interim Storage Site: Annual site environment report, Calendar year 1985

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1986-11-01

The Hazelwood Interim Storage Site (HISS) is presently used for the storage of low-level radioactively contaminated soils. Monitoring results show that the HISS is in compliance with DOE Derived Concentration Guides (DCGs) and radiation protection standards. During 1985, annual average radon concentrations ranged from 10 to 23% of the DCG. The highest external dose rate at the HISS was 287 mrem/yr. The measured background dose rate for the HISS area is 99 mrem/yr. The highest average annual concentration of uranium in surface water monitored in the vicinity of the HISS was 0.7% of the DOE DCG; for /sup 226/Ra itmore » was 0.3% of the applicable DCG, and for /sup 230/Th it was 1.7%. In groundwater, the highest annual average concentration of uranium was 12% of the DCG; for /sup 226/Ra it was 3.6% of the applicable DCG, and for /sup 230/Th it was 1.8%. While there are no concentration guides for stream sediments, the highest concentration of total uranium was 19 pCi/g, the highest concentration of /sup 226/Ra was 4 pCi/g, and the highest concentration of /sup 230/Th was 300 pCi/g. Radon concentrations, external gamma dose rates, and radionuclide concentrations in groundwater at the site were lower than those measured in 1984; radionuclide concentrations in surface water were roughly equivalent to 1984 levels. For sediments, a meaningful comparison with 1984 concentrations cannot be made since samples were obtained at only two locations and were only analyzed for /sup 230/Th. The calculated radiation dose to the maximally exposed individual at the HISS, considering several exposure pathways, was 5.4 mrem, which is 5% of the radiation protection standard.« less

Evaluation on radiation protection aspect and radiological risk at Mukim Belanja repository

NASA Astrophysics Data System (ADS)

Azmi, Siti Nur Aisyah; Kenoh, Hamiza; Majid, Amran Ab.

2016-01-01

Asian Rare Earth (ARE) is a locally incorporated company that operated a mineral processing operation to extract rare earth element. ARE has received much attention from the public since the beginning of their operation until the work of decommissioning and decontamination of the plant. Due to the existence of Naturally Occurring Radioactive Material (NORM) in the residue, the decommissioning and disposal was done by the company in collaboration with the Perak State Government and the Atomic Energy Licensing Board (AELB). The main objective of this study is to review the level of compliance of the existing Radiation Protection Regulations enforced by AELB particularly in the achievement of allowed exposure dose limit. The next objective was to study the impact of the construction of the Mukim Belanja Repository to workers and public. This study was conducted by analyzing documents that were issued and conducting the area monitoring using a Geiger Muller detector (GM) and Sodium Iodide (NaI(Tl)) survey meters. The measurements were made at 5 cm and 1 m from the ground surface at 27 measurement stations. The external doses measured were within the background levels of the surrounding area. The annual effective dose using the highest reading at 5 cm and 1 m from ground surface by GM detector was calculated to be 1.36 mSv/year and 1.21 mSv/year respectively. Whereas the annual effective dose using the highest reading at 5 cm and 1 m from ground surface by using NaI(Tl) detector was calculated to be 3.31 mSv/year and 2.83 mSv/year respectively. The calculated cancer risks from the study showed that the risk is small compared with the risks derived from natural radiation based on global annual radiation dose to humans. This study therefore indicated that the repository is able to constrain the dose exposure from the disposed NORM waste. The study also revealed that the construction of the repository has complied with all the rules and regulations subjected to it. The exposed dose received by the radiation and the public workers during the construction of the repository were below the annual limit i.e. 20 mSv/year and 1mSv/year respectively.

Evaluation on radiation protection aspect and radiological risk at Mukim Belanja repository

DOE Office of Scientific and Technical Information (OSTI.GOV)

Azmi, Siti Nur Aisyah, E-mail: nuclear.aisyahazmi@gmail.com; Kenoh, Hamiza; Majid, Amran Ab.

2016-01-22

Asian Rare Earth (ARE) is a locally incorporated company that operated a mineral processing operation to extract rare earth element. ARE has received much attention from the public since the beginning of their operation until the work of decommissioning and decontamination of the plant. Due to the existence of Naturally Occurring Radioactive Material (NORM) in the residue, the decommissioning and disposal was done by the company in collaboration with the Perak State Government and the Atomic Energy Licensing Board (AELB). The main objective of this study is to review the level of compliance of the existing Radiation Protection Regulations enforcedmore » by AELB particularly in the achievement of allowed exposure dose limit. The next objective was to study the impact of the construction of the Mukim Belanja Repository to workers and public. This study was conducted by analyzing documents that were issued and conducting the area monitoring using a Geiger Muller detector (GM) and Sodium Iodide (NaI(Tl)) survey meters. The measurements were made at 5 cm and 1 m from the ground surface at 27 measurement stations. The external doses measured were within the background levels of the surrounding area. The annual effective dose using the highest reading at 5 cm and 1 m from ground surface by GM detector was calculated to be 1.36 mSv/year and 1.21 mSv/year respectively. Whereas the annual effective dose using the highest reading at 5 cm and 1 m from ground surface by using NaI(Tl) detector was calculated to be 3.31 mSv/year and 2.83 mSv/year respectively. The calculated cancer risks from the study showed that the risk is small compared with the risks derived from natural radiation based on global annual radiation dose to humans. This study therefore indicated that the repository is able to constrain the dose exposure from the disposed NORM waste. The study also revealed that the construction of the repository has complied with all the rules and regulations subjected to it. The exposed dose received by the radiation and the public workers during the construction of the repository were below the annual limit i.e. 20 mSv/year and 1mSv/year respectively.« less

Decadal trend of precipitation and temperature patterns and impacts on snow-related variables in a semiarid region, Sierra Nevada, Spain.

NASA Astrophysics Data System (ADS)

José Pérez-Palazón, María; Pimentel, Rafael; Herrero, Javier; José Polo, María

2016-04-01

In the current context of global change, mountainous areas constitute singular locations in which these changes can be traced. Early detection of significant shifts of snow state variables in semiarid regions can help assess climate variability impacts and future snow dynamics in northern latitudes. The Sierra Nevada mountain range, in southern Spain, is a representative example of snow areas in Mediterranean-climate regions and both monitoring and modelling efforts have been performed to assess this variability and its significant scales. This work presents a decadal trend analysis throughout the 50-yr period 1960-2010 performed on some snow-related variables over Sierra Nevada, in Spain, which is included in the global climate change observatories network around the world. The study area comprises 4583 km2 distributed throughout the five head basins influenced by these mountains, with altitude values ranging from 140 to 3479 m.a.s.l., just 40 km from the Mediterranean coastline. Meteorological variables obtained from 44 weather stations from the National Meteorological Agency were studied and further used as input to the distributed hydrological model WiMMed (Polo et al., 2010), operational at the study area, to obtain selected snow variables. Decadal trends were obtained, together with their statistical significance, over the following variables, averaged over the whole study area: (1) annual precipitation; (2) annual snowfall; annual (3) mean, (4) maximum and (5) minimum daily temperature; annual (6) mean and (7) maximum daily fraction of snow covered areas; (8) annual number of days with snow cover; (9) mean and (10) maximum daily snow water equivalent; (11) annual number of extreme precipitation events; and (12) mean intensity of the annual extreme precipitation events. These variables were also studied over each of the five regions associated to each basin in the range. Globally decreasing decadal trends were obtained for all the meteorological variables, with the exception of the average annual mean and maximum daily temperature. In the case of the snow-related variables, no significant trends are observed at this time scale; nonetheless, a global decreasing rate is predominant in most of the variables. The torrential events are more frequent in the last decades of the study period, with an apparently increasing associated dispersion. This study constitutes a first sound analysis of the long-term observed trends of the snow regime in this area under the context of increasing temperature and decreasing precipitation regimes. The results highlight the complexity of non-linearity in environmental processes in Mediterranean regions, and point out to a significant shift in the precipitation and temperature regime, and thus on the snow-affected hydrological variables in the study area.

Climate-change signals in national atmospheric deposition program precipitation data

USGS Publications Warehouse

Wetherbee, Gregory A.; Mast, M. Alisa

2016-01-01

National Atmospheric Deposition Program (NADP)/National Trends Network precipitation type, snow-season duration, and annual timing of selected chemical wet-deposition maxima vary with latitude and longitude within a 35-year (1979–2013) data record for the contiguous United States and Alaska. From the NADP data collected within the region bounded by 35.6645°–48.782° north latitude and 124°–68° west longitude, similarities in latitudinal and longitudinal patterns of changing snow-season duration, fraction of annual precipitation recorded as snow, and the timing of chemical wet-deposition maxima, suggest that the chemical climate of the atmosphere is linked to physical changes in climate. Total annual precipitation depth has increased 4–6 % while snow season duration has decreased from approximately 7 to 21 days across most of the USA, except in higher elevation regions where it has increased by as much as 21 days. Snow-season precipitation is increasingly comprised of snow, but annually total precipitation is increasingly comprised of liquid precipitation. Meanwhile, maximum ammonium deposition occurs as much as 27 days earlier, and the maximum nitrate: sulfate concentration ratio in wet-deposition occurs approximately 10–21 days earlier in the year. The maximum crustal (calcium + magnesium + potassium) cation deposition occurs 2–35 days earlier in the year. The data suggest that these shifts in the timing of atmospheric wet deposition are linked to a warming climate, but the ecological consequences are uncertain.

10 CFR Appendix B to Part 20 - Annual Limits on Intake (ALIs) and Derived Air Concentrations (DACs) of Radionuclides for...

Code of Federal Regulations, 2014 CFR

2014-01-01

...) a committed effective dose equivalent of 5 rems (stochastic ALI) or (2) a committed dose equivalent of 50 rems to an organ or tissue (non-stochastic ALI). The stochastic ALIs were derived to result in... equivalent to the whole body of 5 rems. The derivation includes multiplying the committed dose equivalent to...

10 CFR Appendix B to Part 20 - Annual Limits on Intake (ALIs) and Derived Air Concentrations (DACs) of Radionuclides for...

Code of Federal Regulations, 2011 CFR

2011-01-01

...) a committed effective dose equivalent of 5 rems (stochastic ALI) or (2) a committed dose equivalent of 50 rems to an organ or tissue (non-stochastic ALI). The stochastic ALIs were derived to result in... equivalent to the whole body of 5 rems. The derivation includes multiplying the committed dose equivalent to...

10 CFR Appendix B to Part 20 - Annual Limits on Intake (ALIs) and Derived Air Concentrations (DACs) of Radionuclides for...

Code of Federal Regulations, 2012 CFR

2012-01-01

...) a committed effective dose equivalent of 5 rems (stochastic ALI) or (2) a committed dose equivalent of 50 rems to an organ or tissue (non-stochastic ALI). The stochastic ALIs were derived to result in... equivalent to the whole body of 5 rems. The derivation includes multiplying the committed dose equivalent to...

10 CFR Appendix B to Part 20 - Annual Limits on Intake (ALIs) and Derived Air Concentrations (DACs) of Radionuclides for...

Code of Federal Regulations, 2010 CFR

2010-01-01

...) a committed effective dose equivalent of 5 rems (stochastic ALI) or (2) a committed dose equivalent of 50 rems to an organ or tissue (non-stochastic ALI). The stochastic ALIs were derived to result in... equivalent to the whole body of 5 rems. The derivation includes multiplying the committed dose equivalent to...

10 CFR Appendix B to Part 20 - Annual Limits on Intake (ALIs) and Derived Air Concentrations (DACs) of Radionuclides for...

Code of Federal Regulations, 2013 CFR

2013-01-01

...) a committed effective dose equivalent of 5 rems (stochastic ALI) or (2) a committed dose equivalent of 50 rems to an organ or tissue (non-stochastic ALI). The stochastic ALIs were derived to result in... equivalent to the whole body of 5 rems. The derivation includes multiplying the committed dose equivalent to...

Radiolead (210)Pb and (210)Po/(210)Pb activity ratios in calcium supplements and the assessment of their possible dose to consumers.

PubMed

Strumińska-Parulska, Dagmara I

2016-08-23

This paper presents the results of pioneer study of the most popular calcium supplements as a potential additional source of radiolead (210)Pb in human diet. The analyzed calcium pharmaceutics contained organic or inorganic calcium compounds; some came from natural sources as mussels' shells, fish extracts, or sedimentary rocks. The idea was to investigate the naturally occurring (210)Pb activity in different calcium supplements and calculate the annual effective radiation dose from radiolead (210)Pb decay in consumed calcium supplement. The results showed (210)Pb concentrations in natural origin calcium supplements (especially sedimentary rocks) were significantly higher. The highest (210)Pb activity concentrations were determined in mineral tablets made from dolomite - 2.97 ± 0.18 mBq g(-1), while the lowest was observed in organic calcium compounds - both calcium lactate - 0.08 ± 0.01 and 0.13 ± 0.01 mBq g(-1). The highest annual radiation dose from (210)Pb taken with 1 tablet of calcium supplement per day was calculated for soluble calcium lactate sample - 1.19 ± 0.03 µSv year(-1), while the highest annual radiation dose from (210)Pb taken daily with 1 g of pure Ca for dolomite - 5.57 ± 0.34 µSv year(-1).

Aspirin is associated with reduced cartilage loss in knee osteoarthritis: Data from a cohort study.

PubMed

Wluka, Anita E; Ding, Changhai; Wang, Yuanyuan; Jones, Graeme; Urquhart, Donna M; Cicuttini, Flavia M

2015-07-01

Aspirin, widely used in the prevention of cardiovascular disease, in low dose, has anti-inflammatory and vasculoprotective effects: both of these processes contribute to the pathogenesis of osteoarthritis. We examined whether use of low dose aspirin affects change in knee cartilage volume in osteoarthritis. Participants from the Melbourne osteoarthritis cohort were classified as users and non-users of aspirin, according to baseline use (≤300 mg/day). Their knees were imaged twice over 2 years. Tibial cartilage volumes were measured and change calculated. Twenty one (18%) of 117 eligible participants were aspirin users. Annual change in medial tibial cartilage volume was -43 mm(3) (95% confidence intervals (CI) -93, 10) in aspirin users and -101 mm(3) (95% CI -125, -77) in non-users (p=0.043 for difference) after adjusting for age, gender, BMI and radiographic severity. Similar results were seen for annual percentage loss (1.9% vs 5.4%, p=0.034). No difference was observed for lateral tibial cartilage change and annual change (p=0.98, 0.87 respectively) Low dose aspirin use was associated with reduced medial tibial cartilage loss over 2 years in people with knee osteoarthritis. This data is hypothesis generating and clinical trials are required to confirm efficacy. If this hypothesis is confirmed, low dose aspirin may be used to reduce the progression of knee osteoarthritis. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Mars surface radiation exposure for solar maximum conditions and 1989 solar proton events

NASA Technical Reports Server (NTRS)

Simonsen, Lisa C.; Nealy, John E.

1992-01-01

The Langley heavy-ion/nucleon transport code, HZETRN, and the high-energy nucleon transport code, BRYNTRN, are used to predict the propagation of galactic cosmic rays (GCR's) and solar flare protons through the carbon dioxide atmosphere of Mars. Particle fluences and the resulting doses are estimated on the surface of Mars for GCR's during solar maximum conditions and the Aug., Sep., and Oct. 1989 solar proton events. These results extend previously calculated surface estimates for GCR's at solar minimum conditions and the Feb. 1956, Nov. 1960, and Aug. 1972 solar proton events. Surface doses are estimated with both a low-density and a high-density carbon dioxide model of the atmosphere for altitudes of 0, 4, 8, and 12 km above the surface. A solar modulation function is incorporated to estimate the GCR dose variation between solar minimum and maximum conditions over the 11-year solar cycle. By using current Mars mission scenarios, doses to the skin, eye, and blood-forming organs are predicted for short- and long-duration stay times on the Martian surface throughout the solar cycle.

Long-Term Simulation of Dust Distribution with the GOCART Model: Correlation with the North Atlantic Oscillation

NASA Technical Reports Server (NTRS)

Ginoux, P.; Prospero, J.; Torres, O.; Chin, M.

2002-01-01

Global distribution of aeolian dust is simulated from 1981 to 1996 with the Goddard Ozone Chemistry Aerosol Radiation and Transport (GOCART) model. The results are assessed with in-situ measurements and the Total Ozone Mapping Spectrometer (TOMS) aerosol products. The annual budget over the different continents and oceans are analyzed. It is found that there is a maximum of 25% difference of global annual emission from the minimum in 1996 to the maximum in 1988. There is a downward trend of dust emission over Africa and East Asia, of 6 and 2 Tg/yr, respectively. The inter-annual variability of dust distribution is analyzed over the North Atlantic and Africa. It is found that in winter most of the North Atlantic and Africa dust loading is correlated with the North Atlantic Oscillation. The GOCART model indicates that a controlling factor of such correlation can be attributed to dust emission from the Sahel. The Bodele depression is the major dust source in winter and its inter-annual variability is highly correlated with the NAO. However, it is not possible to conclude without further analysis that the North Atlantic Oscillation is forcing the inter-annual variability of dust emission and in-turn dust concentration over the North Atlantic.

The Effects of Dextromethorphan on Driving Performance and the Standardized Field Sobriety Test.

PubMed

Perry, Paul J; Fredriksen, Kristian; Chew, Stephanie; Ip, Eric J; Lopes, Ingrid; Doroudgar, Shadi; Thomas, Kelan

2015-09-01

Dextromethorphan (DXM) is abused most commonly among adolescents as a recreational drug to generate a dissociative experience. The objective of the study was to assess driving with and without DXM ingestion. The effects of one-time maximum daily doses of DXM 120 mg versus a guaifenesin 400 mg dose were compared among 40 healthy subjects using a crossover design. Subjects' ability to drive was assessed by their performance in a driving simulator (STISIM® Drive driving simulator software) and by conducting a standardized field sobriety test (SFST) administered 1-h postdrug administration. The one-time dose of DXM 120 mg did not demonstrate driving impairment on the STISIM® Drive driving simulator or increase SFST failures compared to guaifenesin 400 mg. Doses greater than the currently recommended maximum daily dose of 120 mg are necessary to perturb driving behavior. © 2015 American Academy of Forensic Sciences.

Determination of radon and radium concentrations in drinking water samples around the city of Kutahya.

PubMed

Sahin, Latife; Cetinkaya, Hakan; Murat Saç, Müslim; Içhedef, Mutlu

2013-08-01

The concentration of radium and radon has been determined in drinking water samples collected from various locations of Kutahya city, Turkey. The water samples are taken from public water sources and tap water, with the collector chamber method used to measure the radon and radium concentration. The radon concentration ranges between 0.1 and 48.6±1.7 Bq l(-1), while the radium concentration varies from a minimum detectable activity of <0.02-0.7±0.2 Bq l(-1) in Kutahya city. In addition to the radon and radium levels, parameters such as pH, conductivity and temperature of the water, humidity, pressure, elevation and the coordinates of the sampling points have also been measured and recorded. The annual effective dose from radon and radium due to typical water usage has been calculated. The resulting contribution to the annual effective dose due to radon ingestion varies between 0.3 and 124.2 μSv y(-1); the contribution to the annual effective dose due to radium ingestion varies between 0 and 143.3 μSv y(-1); the dose contribution to the stomach due to radon ingestion varies between 0.03 and 14.9 μSv y(-1). The dose contribution due to radon inhalation ranges between 0.3 and 122.5 μSv y(-1), assuming a typical transfer of radon in water to the air. For the overwhelming majority of the Kutahya population, it is determined that the average radiation exposure from drinking water is less than 73.6 µSv y(-1).

210-Polonium studies in some environmental and biological matrices of Domiasiat uranium deposit area, West Khasi Hills, Meghalaya, India.

PubMed

Marbaniang, Deswyn G; Poddar, Raj K; Nongkynrih, Phlis; Khathing, Darlando T

2010-03-01

The study was performed using a silicon surface barrier alpha spectrometer at Bhabha Atomic Research Centre, Mumbai, India. Through the study, the observed (210)Po activity in water sample from different locations in the Domiasiat area ranges from 0.04 to 0.69 Bq/l. The daily and annual intake of (210)Po through water was also estimated and the mean value of 0.72 and 263.61 Bq, respectively, were observed. It is observed that the effective doses through water were higher than the World Health Organization recommended dose of 0.05 mSv/year. The total annual effective doses through terrestrial ingestion for all the locations was studied and the mean annual effective dose was observed to be 0.315 mSv, which, when compared to the worldwide and the Indian values, was observed to be slightly higher. The mean activity in soil is found to be 124.8 +/-5.7 Bq/kg and in meat the activity is 0.43 +/-0.05 Bq/kg. In fishes, an activity of 0.48 +/-0.07 Bq/kg in Garra lamta, 0.29 +/-0.02 Bq/kg in Neolissocheilus hexaganolepis, and 3.3 +/-0.1 Bq/kg in Macrobrachium sp. is observed. Activity concentration in plant samples was analyzed and the activity ranges from 0.020 +/-0.002 to 9.69 +/-0.35 Bq/kg. Committed effective dose by the adult population of the Domiasiat area through intake of (210)Po through these food items was also determined and compared with the Indian average value and the worldwide average value.

Pharmacology of 13-cis-retinoic acid in humans.

PubMed

Kerr, I G; Lippman, M E; Jenkins, J; Myers, C E

1982-05-01

Vitamin A and its analogs (retinoids) have shown great promise for the chemoprevention of cancer as well as being a possible new class of chemotherapeutic agents. A Phase I and II trial of 13-cis-retinoic acid in advanced cancers was initiated, and the clinical pharmacology of the drug was studied. All patients received p.o. 13-cis-retinoic acid starting at 0.5 mg/kg/day, escalating over 4 weeks to a maximum dose of 8 mg/kg/day in divided doses. Although there was a linear correlation of plasma concentration with dose escalation, large inter-individual variations in peak plasma concentrations were noted. At the maximum drug dose, the mean peak plasma concentration was 4 X 10(-6) M. There was little drug accumulation on this schedule, as trough concentrations between p.o. doses often dropped below 1 X 10(-6) M. The drug was metabolized extensively to a metabolite, the concentrations of which exceeding parent 13-cis-retinoic acid concentrations with chronic dosing. Retinol concentrations were below the normal range.

Reconstruction and analysis of erythemal UV radiation time series from Hradec Králové (Czech Republic) over the past 50 years

NASA Astrophysics Data System (ADS)

Čížková, Klára; Láska, Kamil; Metelka, Ladislav; Staněk, Martin

2018-02-01

This paper evaluates the variability of erythemal ultraviolet (EUV) radiation from Hradec Králové (Czech Republic) in the period 1964-2013. The EUV radiation time series was reconstructed using a radiative transfer model and additional empirical relationships, with the final root mean square error of 9.9 %. The reconstructed time series documented the increase in EUV radiation doses in the 1980s and the 1990s (up to 15 % per decade), which was linked to the steep decline in total ozone (10 % per decade). The changes in cloud cover were the major factor affecting the EUV radiation doses especially in the 1960s, 1970s, and at the beginning of the new millennium. The mean annual EUV radiation doses in the decade 2004-2013 declined by 5 %. The factors affecting the EUV radiation doses differed also according to the chosen integration period (daily, monthly, and annually): solar zenith angle was the most important for daily doses, cloud cover, and surface UV albedo for their monthly means, and the annual means of EUV radiation doses were most influenced by total ozone column. The number of days with very high EUV radiation doses increased by 22 % per decade, the increase was statistically significant in all seasons except autumn. The occurrence of the days with very high EUV doses was influenced mostly by low total ozone column (82 % of days), clear-sky or partly cloudy conditions (74 % of days) and by increased surface albedo (19 % of days). The principal component analysis documented that the occurrence of days with very high EUV radiation doses was much affected by the positive phase of North Atlantic Oscillation with an Azores High promontory reaching over central Europe. In the stratosphere, a strong Arctic circumpolar vortex and the meridional inflow of ozone-poor air from the southwest were favorable for the occurrence of days with very high EUV radiation doses. This is the first analysis of the relationship between the high EUV radiation doses and macroscale circulation patterns, and therefore more attention should be given also to other dynamical variables that may affect the solar UV radiation on the Earth surface.

Optimisation of environmental remediation: how to select and use the reference levels.

PubMed

Balonov, M; Chipiga, L; Kiselev, S; Sneve, M; Yankovich, T; Proehl, G

2018-06-01

A number of past industrial activities and accidents have resulted in the radioactive contamination of large areas at many sites around the world, giving rise to a need for remediation. According to the International Commission on Radiological Protection (ICRP) and International Atomic Energy Agency (IAEA), such situations should be managed as existing exposure situations (ExESs). Control of exposure to the public in ExESs is based on the application of appropriate reference levels (RLs) for residual doses. The implementation of this potentially fruitful concept for the optimisation of remediation in various regions is hampered by a lack of practical experience and relevant guidance. This paper suggests a generic methodology for the selection of numeric values of relevant RLs both in terms of residual annual effective dose and derived RLs (DRLs) based on an appropriate dose assessment. The value for an RL should be selected in the range of the annual residual effective dose of 1-20 mSv, depending on the prevailing circumstances for the exposure under consideration. Within this range, RL values should be chosen by the following assessment steps: (a) assessment of the projected dose, i.e. the dose to a representative person without remedial actions by means of a realistic model as opposed to a conservative model; (b) modelling of the residual dose to a representative person following application of feasible remedial actions; and (c) selection of an RL value between the projected and residual doses, taking account of the prevailing social and economic conditions. This paper also contains some recommendations for practical implementation of the selected RLs for the optimisation of public protection. The suggested methodology used for the selection of RLs (in terms of dose) and the calculation of DRLs (in terms of activity concentration in food, ambient dose rate, etc) has been illustrated by a retrospective analysis of post-Chernobyl monitoring and modelling data from the Bryansk region, Russia, 2001. From this example, it follows that analysis of real data leads to the selection of an RL from a relatively narrow annual dose range (in this case, about 2-3 mSv), from which relevant DRLs can be calculated and directly used for optimisation of the remediation programme.

Preventive sparing of spinal cord and brain stem in the initial irradiation of locally advanced head and neck cancers.

PubMed

Farace, Paolo; Piras, Sara; Porru, Sergio; Massazza, Federica; Fadda, Giuseppina; Solla, Ignazio; Piras, Denise; Deidda, Maria Assunta; Amichetti, Maurizio; Possanzini, Marco

2014-01-06

Since reirradiation in recurrent head and neck patients is limited by previous treatment, a marked reduction of maximum doses to spinal cord and brain stem was investigated in the initial irradiation of stage III/IV head and neck cancers. Eighteen patients were planned by simultaneous integrated boost, prescribing 69.3 Gy to PTV1 and 56.1 Gy to PTV2. Nine 6 MV coplanar photon beams at equispaced gantry angles were chosen for each patient. Step-and-shoot IMRT was calculated by direct machine parameter optimization, with the maximum number of segments limited to 80. In the standard plan, optimization considered organs at risk (OAR), dose conformity, maximum dose < 45 Gy to spinal cord and < 50 Gy to brain stem. In the sparing plans, a marked reduction to spinal cord and brain stem were investigated, with/without changes in dose conformity. In the sparing plans, the maximum doses to spinal cord and brain stem were reduced from the initial values (43.5 ± 2.2 Gy and 36.7 ± 14.0 Gy), without significant changes on the other OARs. A marked difference (-15.9 ± 1.9 Gy and -10.1 ± 5.7 Gy) was obtained at the expense of a small difference (-1.3% ± 0.9%) from initial PTV195% coverage (96.6% ± 0.9%). Similar difference (-15.7 ± 2.2 Gy and -10.2 ± 6.1 Gy) was obtained compromising dose conformity, but unaffecting PTV195% and with negligible decrease in PTV295% (-0.3% ± 0.3% from the initial 98.3% ± 0.8%). A marked spinal cord and brain stem preventive sparing was feasible at the expense of a decrease in dose conformity or slightly compromising target coverage. A sparing should be recommended in highly recurrent tumors, to make potential reirradiation safer.

An analysis of collegiate band directors' exposure to sound pressure levels

NASA Astrophysics Data System (ADS)

Roebuck, Nikole Moore

Noise-induced hearing loss (NIHL) is a significant but unfortunate common occupational hazard. The purpose of the current study was to measure the magnitude of sound pressure levels generated within a collegiate band room and determine if those sound pressure levels are of a magnitude that exceeds the policy standards and recommendations of the Occupational Safety and Health Administration (OSHA), and the National Institute of Occupational Safety and Health (NIOSH). In addition, reverberation times were measured and analyzed in order to determine the appropriateness of acoustical conditions for the band rehearsal environment. Sound pressure measurements were taken from the rehearsal of seven collegiate marching bands. Single sample t test were conducted to compare the sound pressure levels of all bands to the noise exposure standards of OSHA and NIOSH. Multiple regression analysis were conducted and analyzed in order to determine the effect of the band room's conditions on the sound pressure levels and reverberation times. Time weighted averages (TWA), noise percentage doses, and peak levels were also collected. The mean Leq for all band directors was 90.5 dBA. The total accumulated noise percentage dose for all band directors was 77.6% of the maximum allowable daily noise dose under the OSHA standard. The total calculated TWA for all band directors was 88.2% of the maximum allowable daily noise dose under the OSHA standard. The total accumulated noise percentage dose for all band directors was 152.1% of the maximum allowable daily noise dose under the NIOSH standards, and the total calculated TWA for all band directors was 93dBA of the maximum allowable daily noise dose under the NIOSH standard. Multiple regression analysis revealed that the room volume, the level of acoustical treatment and the mean room reverberation time predicted 80% of the variance in sound pressure levels in this study.

Assessment of radionuclide concentration and exhalation studies in soil of lesser Himalayas of Jammu and Kashmir, India

NASA Astrophysics Data System (ADS)

Kumar, Ajay; Vij, Raman; Sharma, Sumit; Sarin, Amit; Narang, Saurabh

2018-02-01

Because to extensive utilization of soil as a building/construction stuff, the activities of 238U, 40K, 232Th, and exhalation studies in solid samples have been measured using thallium activated sodium iodide (NaI(Tl)) gamma detector and scintillation-based smart RnDuo monitor. The measured activity concentration of radionuclides lies in the range of 2.76-38.96, 12.47-65.70, and 199-450 Bq/kg for uranium (C U), thorium (C Th), and potassium (C K), respectively. The annual effective dose rate due to radionuclides is within the secure limit suggested by ICRP. The radium equivalent activity of all the samples is under 100 Bq/kg. The maximum outward and inside risk indices of all these samples are below the values of 0.37 and 0.43. No direct correlation has been seen between 238U and its mass exhalation rate as well as 232Th and its surface exhalation rate in soil samples.

Proxy-based reconstruction of erythemal UV doses over Estonia for 1955 2004

NASA Astrophysics Data System (ADS)

Eerme, K.; Veismann, U.; Lätt, S.

2006-08-01

A proxy-based reconstruction of the erythemally-weighted UV doses for 1955-2004 has been performed for the Tartu-Tõravere Meteorological Station (58°16' N, 26°28' E, 70 m a.s.l.) site. The pyrheliometer-measured daily sum of direct irradiance on partly cloudy and clear days, and the pyranometer-measured daily sum of global irradiance on overcast days were used as the cloudiness influence related proxies. The TOMS ozone data have been used for detecting the daily deviations from the climatic value (averaged annual cycle). In 1998-2004, the biases between the measured and reconstructed daily doses in 55.5% of the cases were within ±10% and in 83.5% of the cases within ±20%, on average. In the summer half-year these amounts were 62% and 88%, respectively. In most years the results for longer intervals did not differ significantly, if no correction was made for the daily deviations of total ozone from its climatic value. The annual and summer half-yearly erythemal doses (contributing, on average, 89% of the annual value) agreed within ±2%, except for the years after major volcanic eruptions and one extremely fine weather year (2002). Using the daily relative sunshine duration as a proxy without detailed correction for atmospheric turbidity results in biases of 2-4% in the summer half-yearly dose in the years after major volcanic eruptions and a few other years of high atmospheric turbidity. The year-to-year variations of the summer half-yearly erythemal dose in 1955-2004 were found to be within 92-111% relative to their average value. Exclusion of eight extreme years reduces this range for the remaining to 95-105.5%. Due to the quasi-periodic alternation of wet and dry periods, the interval of cloudy summers 1976-1993 regularly manifests summer half-yearly erythemal dose values lower than the 1955-2004 average. Since 1996/1997 midwinters have been darker than on average.

Effective Dose Calculation Program (EDCP) for the usage of NORM-added consumer product.

PubMed

Yoo, Do Hyeon; Lee, Jaekook; Min, Chul Hee

2018-04-09

The aim of this study is to develop the Effective Dose Calculation Program (EDCP) for the usage of Naturally Occurring Radioactive Material (NORM) added consumer products. The EDCP was developed based on a database of effective dose conversion coefficient and the Matrix Laboratory (MATLAB) program to incorporate a Graphic User Interface (GUI) for ease of use. To validate EDCP, the effective dose calculated with EDCP by manually determining the source region by using the GUI and that by using the reference mathematical algorithm were compared for pillow, waist supporter, eye-patch and sleeping mattress. The results show that the annual effective dose calculated with EDCP was almost identical to that calculated using the reference mathematical algorithm in most of the assessment cases. With the assumption of the gamma energy of 1 MeV and activity of 1 MBq, the annual effective doses of pillow, waist supporter, sleeping mattress, and eye-patch determined using the reference algorithm were 3.444 mSv year -1 , 2.770 mSv year -1 , 4.629 mSv year -1 , and 3.567 mSv year -1 , respectively, while those calculated using EDCP were 3.561 mSv year -1 , 2.630 mSv year -1 , 4.740 mSv year -1 , and 3.780 mSv year -1 , respectively. The differences in the annual effective doses were less than 5%, despite the different calculation methods employed. The EDCP can therefore be effectively used for radiation protection management in the context of the usage of NORM-added consumer products. Additionally, EDCP can be used by members of the public through the GUI for various studies in the field of radiation protection, thus facilitating easy access to the program. Copyright © 2018. Published by Elsevier Ltd.

Inhalation Dose and Source Term Studies in a Tribal Area of Wayanad, Kerala, India

PubMed Central

Damodaran, Ravikumar C.; Kumar, Visnuprasad Ashok; Panakal John, Jojo; Bangaru, Danalakshmi; Natarajan, Chitra; Sathiamurthy, Bala Sundar; Mundiyanikal Thomas, Jose; Mishra, Rosaline

2017-01-01

Among radiation exposure pathways to human beings, inhalation dose is the most prominent one. Radon, thoron, and their progeny contribute more than 50 per cent to the annual effective dose due to natural radioactivity. South west coast of India is classified as a High Natural Background Radioactivity Area and large scale data on natural radioactivity and dosimetry are available from these coastal regions including the Neendakara-Chavara belt in the south of Kerala. However, similar studies and reports from the northern part of Kerala are scarce. The present study involves the data collection and analysis of radon, thoron, and progeny concentration in the Wayanad district of Kerala. The radon concentration was found to be within a range of 12–378 Bq/m3. The thoron concentration varied from 15 to 621 Bq/m3. Progeny concentration of radon and thoron and the diurnal variation of radon were also studied. In order to assess source term, wall and floor exhalation studies have been done for the houses showing elevated concentration of radon and thoron. The average values of radon, thoron, and their progeny are found to be above the Indian average as well as the average values reported from the High Natural Background Radioactivity Areas of Kerala. Exhalation studies of the soil samples collected from the vicinity of the houses show that radon mass exhalation rate varied from below detectable limit (BDL) to a maximum of 80 mBq/kg/h. The thoron surface exhalation rate ranged from BDL to 17470 Bq/m2/h. PMID:28611847

Fifteen-Year Growth of a Thinned White Spruce Plantation

Treesearch

Robert F. Wambach; John H. Cooley

1969-01-01

Mean annual increment at age 38 in a thinned white spruce plantation was 102 cubic feet or 0.85 cords per acre per year. Periodic annual increment during the 15 years after thinning seemed to be maximum for residual basal areas between 100 and 120 square feet per acre. OXFORD: 562.2:174.7 Picca glauca: (775):242

29 CFR 2590.712 - Parity in mental health and substance use disorder benefits.

Code of Federal Regulations, 2014 CFR

2014-07-01

... Affordable Care Act section 1302(c), which establish limitations on annual deductibles for non-grandfathered health plans in the small group market and annual limitations on out-of-pocket maximums for all non... brand name”, “non-preferred brand name”, or “specialty” complies with the rules of paragraph (c)(4)(i...

45 CFR 146.136 - Parity in mental health and substance use disorder benefits.

Code of Federal Regulations, 2014 CFR

2014-10-01

... Affordable Care Act section 1302(c), which establish limitations on annual deductibles for non-grandfathered health plans in the small group market and annual limitations on out-of-pocket maximums for all non... brand name”, “non-preferred brand name”, or “specialty” complies with the rules of paragraph (c)(4)(i...

Vulnerabilities and adaptive capacities of selected southwestern crops to climate change

USDA-ARS?s Scientific Manuscript database

By the middle of the 21st Century, maximum annual temperatures in the Southwest (SW) are expected to increase by 2-4 C with the highest increases occurring in the summer months of Jun-Aug. While annual precipitation may remain similar to 1971-2000 values, Mar-May precipitation in the SW may decline ...

5 CFR 531.606 - Maximum limits on locality rates.

Code of Federal Regulations, 2010 CFR

2010-01-01

... than or equal to the maximum payable scheduled annual rate of pay for GS-15; or (ii) The rate for level... Section 531.606 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT CIVIL SERVICE REGULATIONS PAY... of basic pay payable for level IV of the Executive Schedule. (b)(1) A locality rate for an employee...

Organ dose measurement using Optically Stimulated Luminescence Detector (OSLD) during CT examination

NASA Astrophysics Data System (ADS)

Yusuf, Muhammad; Alothmany, Nazeeh; Abdulrahman Kinsara, Abdulraheem

2017-10-01

This study provides detailed information regarding the imaging doses to patient radiosensitive organs from a kilovoltage computed tomography (CT) scan procedure using OSLD. The study reports discrepancies between the measured dose and the calculated dose from the ImPACT scan, as well as a comparison with the dose from a chest X-ray radiography procedure. OSLDs were inserted in several organs, including the brain, eyes, thyroid, lung, heart, spinal cord, breast, spleen, stomach, liver and ovaries, of the RANDO phantom. Standard clinical scanning protocols were used for each individual site, including the brain, thyroid, lung, breast, stomach, liver and ovaries. The measured absorbed doses were then compared with the simulated dose obtained from the ImPACT scan. Additionally, the equivalent doses for each organ were calculated and compared with the dose from a chest X-ray radiography procedure. Absorbed organ doses measured by OSLD in the RANDO phantom of up to 17 mGy depend on the organ scanned and the scanning protocols used. A maximum 9.82% difference was observed between the target organ dose measured by OSLD and the results from the ImPACT scan. The maximum equivalent organ dose measured during this experiment was equal to 99.899 times the equivalent dose from a chest X-ray radiography procedure. The discrepancies between the measured dose with the OSLD and the calculated dose from the ImPACT scan were within 10%. This report recommends the use of OSLD for measuring the absorbed organ dose during CT examination.

Identifying a maximum tolerated contour in two-dimensional dose-finding

PubMed Central

Wages, Nolan A.

2016-01-01

The majority of Phase I methods for multi-agent trials have focused on identifying a single maximum tolerated dose combination (MTDC) among those being investigated. Some published methods in the area have been based on the notion that there is no unique MTDC, and that the set of dose combinations with acceptable toxicity forms an equivalence contour in two dimensions. Therefore, it may be of interest to find multiple MTDC's for further testing for efficacy in a Phase II setting. In this paper, we present a new dose-finding method that extends the continual reassessment method to account for the location of multiple MTDC's. Operating characteristics are demonstrated through simulation studies, and are compared to existing methodology. Some brief discussion of implementation and available software is also provided. PMID:26910586

SU-E-T-450: How Important Is a Reproducible Breath Hold for DIBH Breast Radiotherapy?

DOE Office of Scientific and Technical Information (OSTI.GOV)

Liu, H; Wentworth, S; Sintay, B

Purpose: Deep inspiration breath hold (DIBH) for left-sided breast cancer has been shown to reduce heart dose. Surface imaging helps to ensure accurate breast positioning, but does not guarantee a reproducible breath hold (BH) at DIBH treatments. We examine the effects of variable BH positions for DIBH treatments. Methods: Twenty-Five patients with free breathing (FB) and DIBH scans were reviewed. Four plans were created for each patient: 1) FB, 2) DIBH, 3) FB-DIBH – the DIBH plans were copied to the FB images and recalculated (image registration was based on breast tissue), and 4) P-DIBH – a partial BH withmore » the heart shifted midway between the FB and DIBH positions. The FB-DIBH plans give “worst case” scenarios for surface imaging DIBH, where the breast is aligned by surface imaging but the patient is not holding their breath. Students t-tests were used to compare dose metrics. Results: The DIBH plans gave lower heart dose and comparable breast coverage versus FB in all cases. The FB-DIBH plans showed no significant difference versus FB plans for breast coverage, mean heart dose, or maximum heart dose (p >= 0.10). The mean heart dose differed between FB-DIBH and FB by < 2 Gy for all cases, the maximum heart dose differed by < 2 Gy for 21 cases. The P-DIBH plans showed significantly lower mean heart dose than FB (p = 0.01). The mean heart doses for the P-DIBH plans were < FB for 22 cases, the maximum dose < FB for 18 cases. Conclusions: A DIBH plan delivered to a FB patient set-up with surface imaging will yield similar dosimetry to a plan created and delivered FB. A DIBH plan delivered with even a partial BH can give reduced heart dose compared to FB techniques when the breast tissue is well aligned.« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ryan, M.T.; Butler, H.M.; Gupton, E.D.

The UCC-ND Employee Identification Badge contains an indium foil disc that is intended for use as a dosimetry screening device in the event of a criticality accident. While it is recognized that indium is not a precise mixed neutron-gamma dosimeter, its activation by neutrons provides adequate means for separating potentially exposed persons into three groups. These groups are: (1) personnel exposed below annual dose limits, (2) personnel exposed above annual dose limits but below 25 rem, and (3) personnel exposed above 25 rem. This screening procedure is designed to facilitate dosimeter processing in order to meet regulatory reporting requirements. Amore » quick method of interpreting induced activity measurements is presented and discussed.« less

Air concentrations of /sup 239/Pu and /sup 240/Pu and potential radiation doses to persons living near Pu-contaminated areas in Palomares, Spain

DOE Office of Scientific and Technical Information (OSTI.GOV)

Iranzo, E.; Salvador, S.; Iranzo, C.E.

1987-04-01

On 17 January 1966, an accident during a refueling operation resulted in the destruction of an air force KC-135 tanker and a B-52 bomber carrying four thermonuclear weapons. Two weapons, whose parachutes opened, were found intact. The others experienced non-nuclear explosion with some burning and release of the fissile fuel at impact. Joint efforts by the United States and Spain resulted in remedial action and a long-term program to monitor the effectiveness of the cleanup. Air concentrations of /sup 239/Pu and /sup 240/Pu have been continuously monitored since the accident. The average annual air concentration for each location was usedmore » to estimate committed dose equivalents for individuals living and working around the air sampling stations. The average annual /sup 239/Pu and /sup 240/Pu air concentrations during the 15-y period corresponding to 1966-1980 and the potential committed dose equivalents for various tissues due to the inhalation of the /sup 239/Pu and /sup 240/Pu average annual air concentration during this period are shown and discussed in the report.« less

Radiation dose rates now and in the future for residents neighboring restricted areas of the Fukushima Daiichi Nuclear Power Plant

PubMed Central

Harada, Kouji H.; Niisoe, Tamon; Imanaka, Mie; Takahashi, Tomoyuki; Amako, Katsumi; Fujii, Yukiko; Kanameishi, Masatoshi; Ohse, Kenji; Nakai, Yasumichi; Nishikawa, Tamami; Saito, Yuuichi; Sakamoto, Hiroko; Ueyama, Keiko; Hisaki, Kumiko; Ohara, Eiji; Inoue, Tokiko; Yamamoto, Kanako; Matsuoka, Yukiyo; Ohata, Hitomi; Toshima, Kazue; Okada, Ayumi; Sato, Hitomi; Kuwamori, Toyomi; Tani, Hiroko; Suzuki, Reiko; Kashikura, Mai; Nezu, Michiko; Miyachi, Yoko; Arai, Fusako; Kuwamori, Masanori; Harada, Sumiko; Ohmori, Akira; Ishikawa, Hirohiko; Koizumi, Akio

2014-01-01

Radiation dose rates were evaluated in three areas neighboring a restricted area within a 20- to 50-km radius of the Fukushima Daiichi Nuclear Power Plant in August–September 2012 and projected to 2022 and 2062. Study participants wore personal dosimeters measuring external dose equivalents, almost entirely from deposited radionuclides (groundshine). External dose rate equivalents owing to the accident averaged 1.03, 2.75, and 1.66 mSv/y in the village of Kawauchi, the Tamano area of Soma, and the Haramachi area of Minamisoma, respectively. Internal dose rates estimated from dietary intake of radiocesium averaged 0.0058, 0.019, and 0.0088 mSv/y in Kawauchi, Tamano, and Haramachi, respectively. Dose rates from inhalation of resuspended radiocesium were lower than 0.001 mSv/y. In 2012, the average annual doses from radiocesium were close to the average background radiation exposure (2 mSv/y) in Japan. Accounting only for the physical decay of radiocesium, mean annual dose rates in 2022 were estimated as 0.31, 0.87, and 0.53 mSv/y in Kawauchi, Tamano, and Haramachi, respectively. The simple and conservative estimates are comparable with variations in the background dose, and unlikely to exceed the ordinary permissible dose rate (1 mSv/y) for the majority of the Fukushima population. Health risk assessment indicates that post-2012 doses will increase lifetime solid cancer, leukemia, and breast cancer incidences by 1.06%, 0.03% and 0.28% respectively, in Tamano. This assessment was derived from short-term observation with uncertainties and did not evaluate the first-year dose and radioiodine exposure. Nevertheless, this estimate provides perspective on the long-term radiation exposure levels in the three regions. PMID:24567380

Trend analysis of hydro-climatic variables in the north of Iran

NASA Astrophysics Data System (ADS)

Nikzad Tehrani, E.; Sahour, H.; Booij, M. J.

2018-04-01

Trend analysis of climate variables such as streamflow, precipitation, and temperature provides useful information for understanding the hydrological changes associated with climate change. In this study, a nonparametric Mann-Kendall test was employed to evaluate annual, seasonal, and monthly trends of precipitation and streamflow for the Neka basin in the north of Iran over a 44-year period (1972 to 2015). In addition, the Inverse Distance Weight (IDW) method was used for annual seasonal, monthly, and daily precipitation trends in order to investigate the spatial correlation between precipitation and streamflow trends in the study area. Results showed a downward trend in annual and winter precipitation (Z < -1.96) and an upward trend in annual maximum daily precipitation. Annual and monthly mean flows for most of the months in the Neka basin decreased by 14% significantly, but the annual maximum daily flow increased by 118%. Results for the trend analysis of streamflow and climatic variables showed that there are statistically significant relationships between precipitation and streamflow (p value < 0.05). Correlation coefficients for Kendall, Spearman's rank and linear regression are 0.43, 0.61, and 0.67, respectively. The spatial presentation of the detected precipitation and streamflow trends showed a downward trend for the mean annual precipitation observed in the upstream part of the study area which is consistent with the streamflow trend. Also, there is a good correlation between monthly and seasonal precipitation and streamflow for all sub-basins (Sefidchah, Gelvard, Abelu). In general, from a hydro-climatic point of view, the results showed that the study area is moving towards a situation with more severe drought events.

Observations and simulations of the ionospheric lunar tide: Seasonal variability

NASA Astrophysics Data System (ADS)

Pedatella, N. M.

2014-07-01

The seasonal variability of the ionospheric lunar tide is investigated using a combination of Constellation Observing System for Meteorology, Ionosphere, and Climate (COSMIC) observations and thermosphere-ionosphere-mesosphere electrodynamics general circulation model (TIME-GCM) simulations. The present study focuses on the seasonal variability of the lunar tide in the ionosphere and its potential connection to the occurrence of stratosphere sudden warmings (SSWs). COSMIC maximum F region electron density (NmF2) and total electron content observations reveal a primarily annual variation of the ionospheric lunar tide, with maximum amplitudes occurring at low latitudes during December-February. Simulations of the lunar tide climatology in TIME-GCM display a similar annual variability as the COSMIC observations. This leads to the conclusion that the annual variability of the lunar tide in the ionosphere is not solely due to the occurrence of SSWs. Rather, the annual variability of the lunar tide in the ionosphere is generated by the seasonal variability of the lunar tide at E region altitudes. However, compared to the observations, the ionospheric lunar tide annual variability is weaker in the climatological simulations which is attributed to the occurrence of SSWs during the majority of the years included in the observations. Introducing a SSW into the TIME-GCM simulation leads to an additional enhancement of the lunar tide during Northern Hemisphere winter, increasing the lunar tide annual variability and resulting in an annual variability that is more consistent with the observations. The occurrence of SSWs can therefore potentially bias lunar tide climatologies, and it is important to consider these effects in studies of the lunar tide in the atmosphere and ionosphere.

Dose inspection and risk assessment on radiation safety for the use of non-medical X-ray machines in Taiwan

NASA Astrophysics Data System (ADS)

Hsu, Fang-Yuh; Hsu, Shih-Ming; Chao, Jiunn-Hsing

2017-11-01

The subject of this study is the on-site visits and inspections of facilities commissioned by the Atomic Energy Council (AEC) in Taiwan. This research was conducted to evaluate the possible dose and dose rate of cabinet-type X-ray equipment with nominal voltages of 30-150 kV and open-beam (portable or handheld) equipment, taking both normal operation and possibly abnormal operation conditions into account. Doses and dose rates were measured using a plastic scintillation survey meter and an electronic personal dosimeter. In total, 401 X-ray machines were inspected, including 139 units with nominal voltages of 30-50 kV X-ray equipment, 140 units with nominal voltages of 50-150 kV, and 122 open-beam (portable or handheld) X-ray equipment. The investigated doses for radiation workers and non-radiation workers operating cabinet-type X-ray equipment under normal safety conditions were all at the background dose level. Several investigated dose rates at the position of 10 cm away from the surface of open-beam (portable or handheld) X-ray equipment were very high, such X-ray machines are used by aeronautical police for the detection of suspected explosives, radiation workers are far away (at least 10 m away) from the X-ray machine during its operation. The doses per operation in X-ray equipment with a 30-50 kV nominal voltage were less than 1 mSv in all cases of abnormal use. Some doses were higher than 1 mSv per operation for X-ray equipment of 50-150 kV nominal voltage X-ray. The maximum dose rates at the beam exit have a very wide range, mostly less than 100 μSv/s and the largest value is about 3.92 mSv/s for open-beam (portable or handheld) X-ray devices. The risk induced by operating X-ray devices with nominal voltages of 30-50 kV is extremely low. The 11.5 mSv dose due to one operation at nominal voltage of 50-150 kV X-ray device is equivalent to the exposure of taking 575 chest X-rays. In the abnormal use of open-beam (portable or handheld) X-ray equipment, the effective dose of 3.92 mSv/s is equivalent to taking 196 chest radiographs within 1 s. This work assessed the annual doses (equivalent and effective doses) and risks of X-ray operator staff as reasonably as possible. The results of this research are helpful to the AEC (competent authority of ionization radiation) to improve the management and perform the safe control of X-ray equipment.

Lightning climatology in the Congo Basin: methodology and first results

NASA Astrophysics Data System (ADS)

Kigotsi, Jean; Soula, Serge; Georgis, Jean-François; Barthe, Christelle

2016-04-01

The global climatology of lightning issued from space observations (OTD and LIS) clearly showed the maximum of the thunderstorm activity is located in a large area of the Congo Basin, especially in the Democratic Republic of Congo (DRC). The first goal of the present study is to compare observations from the World Wide Lightning Location Network (WWLLN) from the Lightning Imaging Sensor (LIS) over a 9-year period (2005-2013) in this 2750 km × 2750 km area. The second goal is to analyse the lightning activity in terms of time and space variability. The detection efficiency (DE) of the WWLLN relative to LIS has increased between 2005 and 2013, typically from about 1.70 % to 5.90 %, in agreement with previous results for other regions of the world. The mean monthly flash rate describes an annual cycle with a maximum between November and March and a minimum between June and August, associated with the ICTZ migration but not exactly symmetrical on both sides of the equator. The diurnal evolution of the flash rate has a maximum between 1400 and 1700 UTC, depending on the reference year, in agreement with previous works in other regions of the world. The annual flash density shows a sharp maximum localized in eastern DRC regardless of the reference year and the period of the year. This annual maximum systematically located west of Kivu Lake corresponds to that previously identified by many authors as the worldwide maximum which Christian et al. (2013) falsely attributed to Rwanda. Another more extended region within the Congo Basin exhibits moderately large values, especially during the beginning of the period analyzed. A comparison of both patterns of lightning density from the WWLLN and from LIS allows to validate the representativeness of this world network and to restitute the total lightning activity in terms of lightning density and rate.

Regulatory Forum Opinion Piece*: Retrospective Evaluation of Doses in the 26-week Tg.rasH2 Mice Carcinogenicity Studies: Recommendation to Eliminate High Doses at Maximum Tolerated Dose (MTD) in Future Studies.

PubMed

Paranjpe, Madhav G; Denton, Melissa D; Vidmar, Tom J; Elbekai, Reem H

2015-07-01

High doses in Tg.rasH2 carcinogenicity studies are usually set at the maximum tolerated dose (MTD), although this dose selection strategy has not been critically evaluated. We analyzed the body weight gains (BWGs), mortality, and tumor response in control and treated groups of 29 Tg.rasH2 studies conducted at BioReliance. Based on our analysis, it is evident that the MTD was exceeded at the high and/or mid-doses in several studies. The incidence of tumors in high doses was lower when compared to the low and mid-doses of both sexes. Thus, we recommend that the high dose in male mice should not exceed one-half of the estimated MTD (EMTD), as it is currently chosen, and the next dose should be one-fourth of the EMTD. Because females were less sensitive to decrements in BWG, the high dose in female mice should not exceed two-third of EMTD and the next dose group should be one-third of EMTD. If needed, a third dose group should be set at one-eighth EMTD in males and one-sixth EMTD in females. In addition, for compounds that do not show toxicity in the range finding studies, a limit dose should be applied for the 26-week carcinogenicity studies. © 2014 by The Author(s).

Toxicokinetics to identify nonlinearities in dose-response and implications for risk assessment

EPA Science Inventory

For presentation at the 45th Annual Symposium of the Society of Toxicology of Canada. The meeting will be held on 4-5 December 2013 at the Ottawa Convention Centre. Toxicokinetics to identify nonlinearities in dose-response and implications for risk assessment. Rory Conolly, Offi...

Editor's choice--Use of disposable radiation-absorbing surgical drapes results in significant dose reduction during EVAR procedures.

PubMed

Kloeze, C; Klompenhouwer, E G; Brands, P J M; van Sambeek, M R H M; Cuypers, P W M; Teijink, J A W

2014-03-01

Because of the increasing number of interventional endovascular procedures with fluoroscopy and the corresponding high annual dose for interventionalists, additional dose-protecting measures are desirable. The purpose of this study was to evaluate the effect of disposable radiation-absorbing surgical drapes in reducing scatter radiation exposure for interventionalists and supporting staff during an endovascular aneurysm repair (EVAR) procedure. This was a randomized control trial in which 36 EVAR procedures were randomized between execution with and without disposable radiation-absorbing surgical drapes (Radpad: Worldwide Innovations & Technologies, Inc., Kansas City, US, type 5511A). Dosimetric measurements were performed on the interventionalist (hand and chest) and theatre nurse (chest) with and without the use of the drapes to obtain the dose reduction and effect on the annual dose caused by the drapes. Use of disposable radiation-absorbing surgical drapes resulted in dose reductions of 49%, 55%, and 48%, respectively, measured on the hand and chest of the interventionalist and the chest of the theatre nurse. The use of disposable radiation-absorbing surgical drapes significantly reduces scatter radiation exposure for both the interventionalist and the supporting staff during EVAR procedures. Copyright © 2013 European Society for Vascular Surgery. Published by Elsevier Ltd. All rights reserved.

Radionuclide concentrations in soil and lifetime cancer risk due to gamma radioactivity in Kirklareli, Turkey.

PubMed

Taskin, H; Karavus, M; Ay, P; Topuzoglu, A; Hidiroglu, S; Karahan, G

2009-01-01

The objective of this study is to evaluate and map soil radionuclides' activity concentrations and environmental outdoor gamma dose rates (terrestrial and cosmic) in Kirklareli, Turkey. The excess lifetime cancer risks are also calculated. Outdoor gamma dose rates were determined in 230 sampling stations and soil samples were taken from 177 locations. The coordinates of the readings were determined by the Global Positioning System (GPS). The outdoor gamma dose rates were determined by Eberline smart portable device (ESP-2) and measurements were taken in air for two minutes at 1m from the ground. The average outdoor gamma dose rate was 118+/-34nGyh(-1). Annual effective gamma dose of Kirklareli was 144microSv and the excess lifetime cancer risk of 5.0x10(-4). Soil samples were analyzed by gamma spectroscopy. The average 226Ra, 238U, 232Th, 137Cs, and 40K activities were 37+/-18Bqkg(-1), 28+/-13Bqkg(-1), 40+/-18Bqkg(-1), 8+/-5Bqkg(-1) and 667+/-281Bqkg(-1), respectively. The average soil radionuclides' concentrations of Kirklareli were within the worldwide range although some extreme values had been determined. Annual effective gamma doses and the excess lifetime risks of cancer were higher than the world's average.

Carbon dynamics in an almond orchard soil amended with raw and treated pig slurry

NASA Astrophysics Data System (ADS)

Domínguez, Sara G.; Zornoza, Raúl; Faz, Ángel

2010-05-01

In SE Spain, intensive farming is very common which supposes the generation of great amounts of pig slurries. These residues cause many storage problems due to their pollution capacity. A good management of them is necessary to avoid damages to the environment. The use of this effluent as fertilizer is a usual practice that in the correct dose is a good amend and important for sustainable development, but in excess can be a risk of polluting and damaging soil, water and crop conditions. Pig slurry is a source of many nutrients and specially rich in organic matter. The main objective of this study is to determine changes in soil organic carbon dynamics resulting from raw and treated slurry amendments applied in different doses. The experimental area is an almond orchard located in Cartagena (SE Spain). The climate of the area is semiarid Mediterranean with mean annual temperature of 18°C and mean annual rainfall of 275 mm. A total of 10 plots (12 m x 30 m) were designed, one of them being the control without fertilizer. Surface soil samples (0-25 cm) were collected in September 2009. Three different treatments were applied, raw slurry, the effluent obtained after solid-liquid separation and solid manure, all of them in three doses being the first one of 170 kg N/ha, (maximum permitted in nitrates directive 91/676/CEE), and the others two and three times the first one. Soil biochemical parameters are rapid indicators of changes in soil quality. According to this, total organic carbon, soil microbial biomass carbon, soluble carbon, and β-glucosidase, β-galactosidase and arylesterase activities were measured in order to assess some soil biochemical conditions and carbon dynamics in terms of the different treatments. As we expected, the use of these organic fertilizers rich in organic matter, had an effect on soil carbon and soil microbial activity resulting in an increase in most of the parameters; total organic carbon and β-galactosidase activity showed the biggest increment comparing to control. No pattern was observed among fertilizer doses, without big differences among them in most properties. We can conclude that the use of pig slurry as organic fertilizer incorporates great amounts of organic matter to the soil in its different forms, including soluble and microorganisms biomass, which has a positive effect encouraging the application of this agricultural management so that soil can act as C sink, in order to mitigate global warming. Thus, this procedure can be included in the strategies to increase the soil carbon sequestration. According to carbon dynamics, doses are not important, without risks of soluble carbon leaching.

SU-E-T-62: Cardiac Toxicity in Dynamic Conformal Arc Therapy, Intensity-Modulated Radiation Therapy and Volumetric Modulated Arc Therapy of Lung Cancers

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ming, X; Zhang, Y; Yale University, New Haven, CT, US

2014-06-01

Purpose: The cardiac toxicity for lung cancer patients, each treated with dynamic conformal arc therapy (DAT), intensity-modulated radiation therapy (IMRT), or volumetric modulated arc therapy (VMAT) is investigated. Methods: 120 lung patients were selected for this study: 25 treated with DAT, 50 with IMRT and 45 with VMAT. For comparison, all plans were generated in the same treatment planning system, normalized such that the 100% isodose lines encompassed 95% of planning target volume. The plan quality was evaluated in terms of homogeneity index (HI) and 95% conformity index (%95 CI) for target dose coverage and mean dose, maximum dose, V{submore » 30} Gy as well as V{sub 5} Gy for cardiac toxicity analysis. Results: When all the plans were analyzed, the VMAT plans offered the best target coverage with 95% CI = 0.992 and HI = 1.23. The DAT plans provided the best heart sparing with mean heart dose = 2.3Gy and maximum dose = 11.6Gy, as compared to 5.7 Gy and 31.1 Gy by IMRT as well as 4.6 Gy and 30.9 Gy by VMAT. The mean V30Gy and V5Gy of the heart in the DAT plans were up to 11.7% lower in comparison to the IMRT and VMAT plans. When the tumor volume was considered, the VMAT plans spared up to 70.9% more doses to the heart when the equivalent diameter of the tumor was larger than 4cm. Yet the maximum dose to the heart was reduced the most in the DAT plans with up to 139.8% less than that of the other two plans. Conclusion: Overall, the VMAT plans achieved the best target coverage among the three treatment modalities, and would spare the heart the most for the larger tumors. The DAT plans appeared advantageous in delivering the least maximum dose to the heart as compared to the IMRT and VMAT plans.« less

The Advantages of Collimator Optimization for Intensity Modulated Radiation Therapy

NASA Astrophysics Data System (ADS)

Doozan, Brian

The goal of this study was to improve dosimetry for pelvic, lung, head and neck, and other cancers sites with aspherical planning target volumes (PTV) using a new algorithm for collimator optimization for intensity modulated radiation therapy (IMRT) that minimizes the x-jaw gap (CAX) and the area of the jaws (CAA) for each treatment field. A retroactive study on the effects of collimator optimization of 20 patients was performed by comparing metric results for new collimator optimization techniques in Eclipse version 11.0. Keeping all other parameters equal, multiple plans are created using four collimator techniques: CA 0, all fields have collimators set to 0°, CAE, using the Eclipse collimator optimization, CAA, minimizing the area of the jaws around the PTV, and CAX, minimizing the x-jaw gap. The minimum area and the minimum x-jaw angles are found by evaluating each field beam's eye view of the PTV with ImageJ and finding the desired parameters with a custom script. The evaluation of the plans included the monitor units (MU), the maximum dose of the plan, the maximum dose to organs at risk (OAR), the conformity index (CI) and the number of fields that are calculated to split. Compared to the CA0 plans, the monitor units decreased on average by 6% for the CAX method with a p-value of 0.01 from an ANOVA test. The average maximum dose remained within 1.1% difference between all four methods with the lowest given by CAX. The maximum dose to the most at risk organ was best spared by the CAA method, which decreased by 0.62% compared to the CA0. Minimizing the x-jaws significantly reduced the number of split fields from 61 to 37. In every metric tested the CAX optimization produced comparable or superior results compared to the other three techniques. For aspherical PTVs, CAX on average reduced the number of split fields, lowered the maximum dose, minimized the dose to the surrounding OAR, and decreased the monitor units. This is achieved while maintaining the same control of the PTV.

EnviroAtlas - Biological nitrogen fixation in natural/semi-natural ecosystems by 12-digit HUC for the Conterminous United States, 2006

EPA Pesticide Factsheets

This EnviroAtlas dataset contains data on the mean biological nitrogen fixation in natural/semi-natural ecosystems per 12-digit Hydrologic Unit (HUC) in 2006. Biological N fixation (BNF) in natural/semi-natural ecosystems was estimated using a correlation with actual evapotranspiration (AET). This correlation is based on a global meta-analysis of BNF in natural/semi-natural ecosystems (Cleveland et al. 1999). AET estimates for 2006 were calculated using a regression equation describing the correlation of AET with climate (average annual daily temperature, average annual minimum daily temperature, average annual maximum daily temperature, and annual precipitation) and land use/land cover variables in the conterminous US (Sanford and Selnick 2013). Data describing annual average minimum and maximum daily temperatures and total precipitation for 2006 were acquired from the PRISM climate dataset (http://prism.oregonstate.edu). Average annual climate data were then calculated for individual 12-digit USGS Hydrologic Unit Codes (HUC12s; http://water.usgs.gov/GIS/huc.html; 22 March 2011 release) using the Zonal Statistics tool in ArcMap 10.0. AET for individual HUC12s was estimated using equations described in Sanford and Selnick (2013). BNF in natural/semi-natural ecosystems within individual HUC12s was modeled with an equation describing the statistical relationship between BNF (kg N ha-1 yr-1) and actual evapotranspiration (AET; cm yr-1) and scaled to the proportion

Survey of patient knowledge related to acetaminophen recognition, dosing, and toxicity.

PubMed

Hornsby, Lori B; Whitley, Heather P; Hester, E Kelly; Thompson, Melissa; Donaldson, Amy

2010-01-01

To assess patient knowledge regarding acetaminophen dosing, toxicity, and recognition of acetaminophen-containing products. Descriptive, nonexperimental, cross-sectional study. Alabama, January 2007 to February 2008. 284 patients at four outpatient medical facilities. 12-item investigator-administered questionnaire. Degree of patient knowledge regarding acetaminophen safety, dosing recommendations, toxicity, alternative names and abbreviations, and products. Two-thirds of the 284 patients completing the survey reported current or recent use of pain, cold, or allergy medication. Of these, 25% reported knowing the active ingredient. Of patients, 46% and 13% knew that "acetaminophen" and "APAP," respectively, were synonymous with "Tylenol." Several patients (12%) believed that ingesting a harmful amount of acetaminophen was difficult or impossible. One-third of patients correctly identified the maximum daily dose, 10% reported a dose greater than 4 g, 25% were unsure of the dose, and 7% were unsure whether a maximum dose existed. One-half recognized liver damage as the primary toxicity. Results were similar between acetaminophen users and nonusers. Deficiencies were found in patient knowledge regarding acetaminophen recognition, dosing, and potential for toxicity. The development of effective educational initiatives is warranted to ensure patient awareness and limit the potential for acetaminophen overdose.

Comparison of depth-dose distributions of proton therapeutic beams calculated by means of logical detectors and ionization chamber modeled in Monte Carlo codes

NASA Astrophysics Data System (ADS)

Pietrzak, Robert; Konefał, Adam; Sokół, Maria; Orlef, Andrzej

2016-08-01

The success of proton therapy depends strongly on the precision of treatment planning. Dose distribution in biological tissue may be obtained from Monte Carlo simulations using various scientific codes making it possible to perform very accurate calculations. However, there are many factors affecting the accuracy of modeling. One of them is a structure of objects called bins registering a dose. In this work the influence of bin structure on the dose distributions was examined. The MCNPX code calculations of Bragg curve for the 60 MeV proton beam were done in two ways: using simple logical detectors being the volumes determined in water, and using a precise model of ionization chamber used in clinical dosimetry. The results of the simulations were verified experimentally in the water phantom with Marcus ionization chamber. The average local dose difference between the measured relative doses in the water phantom and those calculated by means of the logical detectors was 1.4% at first 25 mm, whereas in the full depth range this difference was 1.6% for the maximum uncertainty in the calculations less than 2.4% and for the maximum measuring error of 1%. In case of the relative doses calculated with the use of the ionization chamber model this average difference was somewhat greater, being 2.3% at depths up to 25 mm and 2.4% in the full range of depths for the maximum uncertainty in the calculations of 3%. In the dose calculations the ionization chamber model does not offer any additional advantages over the logical detectors. The results provided by both models are similar and in good agreement with the measurements, however, the logical detector approach is a more time-effective method.

Phase I Study of Daily Irinotecan as a Radiation Sensitizer for Locally Advanced Pancreatic Cancer

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fouchardiere, Christelle de la, E-mail: delafo@lyon.fnclcc.f; Negrier, Sylvie; Labrosse, Hugues

2010-06-01

Purpose: The study aimed to determine the maximum tolerated dose of daily irinotecan given with concomitant radiotherapy in patients with locally advanced adenocarcinoma of the pancreas. Methods and Materials: Between September 2000 and March 2008, 36 patients with histologically proven unresectable pancreas adenocarcinoma were studied prospectively. Irinotecan was administered daily, 1 to 2 h before irradiation. Doses were started at 6 mg/m{sup 2} per day and then escalated by increments of 2 mg/m{sup 2} every 3 patients. Radiotherapy was administered in 2-Gy fractions, 5 fractions per week, up to a total dose of 50 Gy to the tumor volume. Inoperabilitymore » was confirmed by a surgeon involved in a multidisciplinary team. All images and responses were centrally reviewed by radiologists. Results: Thirty-six patients were enrolled over a period of 8 years through eight dose levels (6 mg/m{sup 2} to 20 mg/m{sup 2} per day). The maximum tolerated dose was determined to be 18 mg/m{sup 2} per day. The dose-limiting toxicities were nausea/vomiting, diarrhea, anorexia, dehydration, and hypokalemia. The median survival time was 12.6 months with a median follow-up of 53.8 months. The median progression-free survival time was 6.5 months, and 4 patients (11.4%) with very good responses could undergo surgery. Conclusions: The maximum tolerated dose of irinotecan is 18 mg/m{sup 2} per day for 5 weeks. Dose-limiting toxicities are mainly gastrointestinal. Even though efficacy was not the aim of this study, the results are very promising, with a median survival time of 12.6 months.« less

Model-Based Dose Selection for Intravaginal Ring Formulations Releasing Anastrozole and Levonorgestrel Intended for the Treatment of Endometriosis Symptoms.

PubMed

Reinecke, Isabel; Schultze-Mosgau, Marcus-Hillert; Nave, Rüdiger; Schmitz, Heinz; Ploeger, Bart A

2017-05-01

Pharmacokinetics (PK) of anastrozole (ATZ) and levonorgestrel (LNG) released from an intravaginal ring (IVR) intended to treat endometriosis symptoms were characterized, and the exposure-response relationship focusing on the development of large ovarian follicle-like structures was investigated by modeling and simulation to support dose selection for further studies. A population PK analysis and simulations were performed for ATZ and LNG based on clinical phase 1 study data from 66 healthy women. A PK/PD model was developed to predict the probability of a maximum follicle size ≥30 mm and the potential contribution of ATZ beside the known LNG effects. Population PK models for ATZ and LNG were established where the interaction of LNG with sex hormone-binding globulin (SHBG) as well as a stimulating effect of estradiol on SHBG were considered. Furthermore, simulations showed that doses of 40 μg/d LNG combined with 300, 600, or 1050 μg/d ATZ reached anticipated exposure levels for both drugs, facilitating selection of ATZ and LNG doses in the phase 2 dose-finding study. The main driver for the effect on maximum follicle size appears to be unbound LNG exposure. A 50% probability of maximum follicle size ≥30 mm was estimated for 40 μg/d LNG based on the exposure-response analysis. ATZ in the dose range investigated does not increase the risk for ovarian cysts as occurs with LNG at a dose that does not inhibit ovulation. © 2016, The American College of Clinical Pharmacology.

4D Optimization of Scanned Ion Beam Tracking Therapy for Moving Tumors

PubMed Central

Eley, John Gordon; Newhauser, Wayne David; Lüchtenborg, Robert; Graeff, Christian; Bert, Christoph

2014-01-01

Motion mitigation strategies are needed to fully realize the theoretical advantages of scanned ion beam therapy for patients with moving tumors. The purpose of this study was to determine whether a new four-dimensional (4D) optimization approach for scanned-ion-beam tracking could reduce dose to avoidance volumes near a moving target while maintaining target dose coverage, compared to an existing 3D-optimized beam tracking approach. We tested these approaches computationally using a simple 4D geometrical phantom and a complex anatomic phantom, that is, a 4D computed tomogram of the thorax of a lung cancer patient. We also validated our findings using measurements of carbon-ion beams with a motorized film phantom. Relative to 3D-optimized beam tracking, 4D-optimized beam tracking reduced the maximum predicted dose to avoidance volumes by 53% in the simple phantom and by 13% in the thorax phantom. 4D-optimized beam tracking provided similar target dose homogeneity in the simple phantom (standard deviation of target dose was 0.4% versus 0.3%) and dramatically superior homogeneity in the thorax phantom (D5-D95 was 1.9% versus 38.7%). Measurements demonstrated that delivery of 4D-optimized beam tracking was technically feasible and confirmed a 42% decrease in maximum film exposure in the avoidance region compared with 3D-optimized beam tracking. In conclusion, we found that 4D-optimized beam tracking can reduce the maximum dose to avoidance volumes near a moving target while maintaining target dose coverage, compared with 3D-optimized beam tracking. PMID:24889215

4D optimization of scanned ion beam tracking therapy for moving tumors

NASA Astrophysics Data System (ADS)

Eley, John Gordon; Newhauser, Wayne David; Lüchtenborg, Robert; Graeff, Christian; Bert, Christoph

2014-07-01

Motion mitigation strategies are needed to fully realize the theoretical advantages of scanned ion beam therapy for patients with moving tumors. The purpose of this study was to determine whether a new four-dimensional (4D) optimization approach for scanned-ion-beam tracking could reduce dose to avoidance volumes near a moving target while maintaining target dose coverage, compared to an existing 3D-optimized beam tracking approach. We tested these approaches computationally using a simple 4D geometrical phantom and a complex anatomic phantom, that is, a 4D computed tomogram of the thorax of a lung cancer patient. We also validated our findings using measurements of carbon-ion beams with a motorized film phantom. Relative to 3D-optimized beam tracking, 4D-optimized beam tracking reduced the maximum predicted dose to avoidance volumes by 53% in the simple phantom and by 13% in the thorax phantom. 4D-optimized beam tracking provided similar target dose homogeneity in the simple phantom (standard deviation of target dose was 0.4% versus 0.3%) and dramatically superior homogeneity in the thorax phantom (D5-D95 was 1.9% versus 38.7%). Measurements demonstrated that delivery of 4D-optimized beam tracking was technically feasible and confirmed a 42% decrease in maximum film exposure in the avoidance region compared with 3D-optimized beam tracking. In conclusion, we found that 4D-optimized beam tracking can reduce the maximum dose to avoidance volumes near a moving target while maintaining target dose coverage, compared with 3D-optimized beam tracking.

Long-term Evaluation of Radiation-Induced Optic Neuropathy After Single-Fraction Stereotactic Radiosurgery

DOE Office of Scientific and Technical Information (OSTI.GOV)

Leavitt, Jacqueline A., E-mail: leavitt.jacqueline@mayo.edu; Stafford, Scott L.; Link, Michael J.

2013-11-01

Purpose: To determine the long-term risk of radiation-induced optic neuropathy (RION) in patients having single-fraction stereotactic radiosurgery (SRS) for benign skull base tumors. Methods and Materials: Retrospective review of 222 patients having Gamma Knife radiosurgery for benign tumors adjacent to the anterior visual pathway (AVP) between 1991 and 1999. Excluded were patients with prior or concurrent external beam radiation therapy or SRS. One hundred twenty-nine patients (58%) had undergone previous surgery. Tumor types included confirmed World Health Organization grade 1 or presumed cavernous sinus meningioma (n=143), pituitary adenoma (n=72), and craniopharyngioma (n=7). The maximum dose to the AVP was ≤8.0more » Gy (n=126), 8.1-10.0 Gy (n=39), 10.1-12.0 Gy (n=47), and >12 Gy (n=10). Results: The mean clinical and imaging follow-up periods were 83 and 123 months, respectively. One patient (0.5%) who received a maximum radiation dose of 12.8 Gy to the AVP developed unilateral blindness 18 months after SRS. The chance of RION according to the maximum radiation dose received by the AVP was 0 (95% confidence interval [CI] 0-3.6%), 0 (95% CI 0-10.7%), 0 (95% CI 0-9.0%), and 10% (95% CI 0-43.0%) for patients receiving ≤8 Gy, 8.1-10.0 Gy, 10.1-12.0 Gy, and >12 Gy, respectively. The overall risk of RION in patients receiving >8 Gy to the AVP was 1.0% (95% CI 0-6.2%). Conclusions: The risk of RION after single-fraction SRS in patients with benign skull base tumors who have no prior radiation exposure is very low if the maximum dose to the AVP is ≤12 Gy. Physicians performing single-fraction SRS should remain cautious when treating lesions adjacent to the AVP, especially when the maximum dose exceeds 10 Gy.« less

Determination of concentration factors for Cs-137 and Ra-226 in the mullet species Chelon labrosus (Mugilidae) from the South Adriatic Sea.

PubMed

Antovic, Ivanka; Antovic, Nevenka M

2011-07-01

Concentration factors for Cs-137 and Ra-226 transfer from seawater, and dried sediment or mud with detritus, have been determined for whole, fresh weight, Chelon labrosus individuals and selected organs. Cesium was detected in 5 of 22 fish individuals, and its activity ranged from 1.0 to 1.6 Bq kg(-1). Radium was detected in all fish, and ranged from 0.4 to 2.1 Bq kg(-1), with an arithmetic mean of 1.0 Bq kg(-1). In regards to fish organs, cesium activity concentration was highest in muscles (maximum - 3.7 Bq kg(-1)), while radium was highest in skeletons (maximum - 25 Bq kg(-1)). Among cesium concentration factors, those for muscles were the highest (from seawater - an average of 47, from sediment - an average of 3.3, from mud with detritus - an average of 0.8). Radium concentration factors were the highest for skeleton (from seawater - an average of 130, from sediment - an average of 1.8, from mud with detritus - an average of 1.5). Additionally, annual intake of cesium and radium by human adults consuming muscles of this fish species has been estimated to provide, in aggregate, an effective dose of about 4.1 μSv y(-1). 2011 Elsevier Ltd. All rights reserved.

Soft-tissue allografts terminally sterilized with an electron beam are biomechanically equivalent to aseptic, nonsterilized tendons.

PubMed

Elenes, Egleide Y; Hunter, Shawn A

2014-08-20

Allograft safety is contingent on effective sterilization. However, current sterilization methods have been associated with decreased biomechanical strength and higher failure rates of soft-tissue allografts. In this study, electron beam (e-beam) sterilization was explored as an alternative sterilization method to preserve biomechanical integrity. We hypothesized that e-beam sterilization would not significantly alter the biomechanical properties of tendon allograft compared with aseptic, nonsterilized controls and gamma-irradiated grafts. Separate sets of forty fresh-frozen tibialis tendon allografts (four from each of ten donors) and forty bisected bone-patellar tendon-bone (BTB) allografts (four from each of ten donors) were randomly assigned to four study groups. One group received a 17.1 to 21.0-kGy gamma radiation dose; two other groups were sterilized with an e-beam at either a high (17.1 to 21.0-kGy) or low (9.2 to 12.2-kGy) dose. A fourth group served as nonsterilized controls. Each graft was cyclically loaded to 200 N of tension for 2000 cycles at a frequency of 2 Hz, allowed to relax for five minutes, and then tested in tension until failure at a 100%/sec strain rate. One-way analysis of variance testing was used to identify significant differences. Tibialis tendons sterilized with both e-beam treatments and with gamma irradiation exhibited values for cyclic tendon elongation, maximum load, maximum displacement, stiffness, maximum stress, maximum strain, and elastic modulus that were not significantly different from those of nonsterilized controls. BTB allografts sterilized with the high e-beam dose and with gamma irradiation were not significantly different in cyclic tendon elongation, maximum load, maximum displacement, stiffness, maximum stress, maximum strain, and elastic modulus from nonsterilized controls. BTB allografts sterilized with the e-beam at the lower dose were significantly less stiff than nonsterilized controls (p = 0.014) but did not differ from controls in any other properties. The difference in stiffness likely resulted from variations in tendon size rather than the treatments, as the elastic moduli of the groups were similar. The biomechanical properties of tibialis and BTB allografts sterilized with use of an e-beam at a dose range of 17.1 to 21.0 kGy were not different from those of aseptic, nonsterilized controls or gamma-irradiated allografts. E-beam sterilization can be a viable method to produce safe and biomechanically uncompromised soft-tissue allografts. Copyright © 2014 by The Journal of Bone and Joint Surgery, Incorporated.

Effects of a prostagrandin EP4-receptor agonist ONO-AE1-329 on the left ventricular pressure-volume relationship in the halothane-anesthetized dogs.

PubMed

Honda, Atsushi; Nakamura, Yuji; Ohara, Hiroshi; Cao, Xin; Nomura, Hiroaki; Katagi, Jun; Wada, Takeshi; Izumi-Nakaseko, Hiroko; Ando, Kentaro; Sugiyama, Atsushi

2016-03-15

Cardiac effects of a prostagrandin EP4-receptor agonist ONO-AE1-329 were assessed in the halothane-anesthetized dogs under the monitoring of left ventricular pressure-volume relationship, which were compared with those of clinically recommended doses of dopamine, dobutamine and milrinone (n=4-5 for each treatment). ONO-AE1-329 was intravenously administered in doses of 0.3, 1 and 3 ng/kg/min for 10 min with a pause of 20 min. Dopamine in a dose of 3 µg/kg/min for 10 min, dobutamine in a dose of 1 µg/kg/min for 10 min and milrinone in a dose of 5 µg/kg/min for 10 min followed by 0.5 µg/kg/min for 10 min were intravenously administered. Low dose of ONO-AE1-329 increased the stroke volume. Middle dose of ONO-AE1-329 increased the cardiac output, left ventricular end-diastolic volume, ejection fraction, maximum upstroke/downstroke velocities of the left ventricular pressure and external work, but decreased the end-systolic pressure and internal work besides the change by the low dose. High dose of ONO-AE1-329 increased the heart rate and maximum elastance, but decreased the end-systolic volume besides the changes by the middle dose. Dopamine, dobutamine and milrinone exerted essentially similar cardiac effects to ONO-AE1-329, but they did not significantly change the end-diastolic volume, end-systolic volume, stroke volume, ejection fraction, end-systolic pressure, maximum elastance, external work or internal work. Thus, EP4-receptor stimulation by ONO-AE1-329 may have potential to better promote the passive ventricular filling than the conventional cardiotonic drugs, which could become a candidate of novel therapeutic strategy for the treatment of heart failure with preserved ejection fraction. Copyright © 2016 Elsevier B.V. All rights reserved.

External beam boost versus interstitial high-dose-rate brachytherapy boost in the adjuvant radiotherapy following breast-conserving therapy in early-stage breast cancer: a dosimetric comparison

PubMed Central

Melchert, Corinna; Kovács, György

2016-01-01

Purpose This study aims to compare the dosimetric data of local tumor's bed dose escalation (boost) with photon beams (external beam radiation therapy – EBRT) versus high-dose-rate interstitial brachytherapy (HDR-BT) after breast-conserving treatment in women with early-stage breast cancer. Material and methods We analyzed the treatment planning data of 136 irradiated patients, treated between 2006 and 2013, who underwent breast-conserving surgery and adjuvant whole breast irradiation (WBI; 50.4 Gy) and boost (HDR-BT: 10 Gy in one fraction [n = 36]; EBRT: 10 Gy in five fractions [n = 100]). Organs at risk (OAR; heart, ipsilateral lung, skin, most exposed rib segment) were delineated. Dosimetric parameters were calculated with the aid of dose-volume histograms (DVH). A non-parametric test was performed to compare the two different boost forms. Results There was no difference for left-sided cancers regarding the maximum dose to the heart (HDR-BT 29.8% vs. EBRT 29.95%, p = 0.34). The maximum doses to the other OAR were significantly lower for HDR-BT (Dmax lung 47.12% vs. 87.7%, p < 0.01; rib 61.17% vs. 98.5%, p < 0.01; skin 57.1% vs. 94.75%, p < 0.01; in the case of right-sided breast irradiation, dose of the heart 6.00% vs. 16.75%, p < 0.01). Conclusions Compared to EBRT, local dose escalation with HDR-BT presented a significant dose reduction to the investigated OAR. Only left-sided irradiation showed no difference regarding the maximum dose to the heart. Reducing irradiation exposure to OAR could result in a reduction of long-term side effects. Therefore, from a dosimetric point of view, an interstitial boost complementary to WBI via EBRT seems to be more advantageous in the adjuvant radiotherapy of breast cancer. PMID:27648082

Phase I Trial of Bortezomib and Concurrent External Beam Radiation in Patients With Advanced Solid Malignancies

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pugh, Thomas J.; Chen Changhu; Rabinovitch, Rachel

Purpose: To determine the maximal tolerated dose of bortezomib with concurrent external beam radiation therapy in patients with incurable solid malignant tumors requiring palliative therapy. Methods and Materials: An open label, dose escalation, phase I clinical trial evaluated the safety of three dose levels of bortezomib administered intravenously (1.0 mg/m{sup 2}, 1.3 mg/m{sup 2}, and 1.6 mg/m{sup 2}/ dose) once weekly with concurrent radiation in patients with histologically confirmed solid tumors and a radiographically appreciable lesion suitable for palliative radiation therapy. All patients received 40 Gy in 16 fractions to the target lesion. Dose-limiting toxicity was the primary endpoint, definedmore » as any grade 4 hematologic toxicity, any grade {>=}3 nonhematologic toxicity, or any toxicity requiring treatment to be delayed for {>=}2 weeks. Results: A total of 12 patients were enrolled. Primary sites included prostate (3 patients), head and neck (3 patients), uterus (1 patient), abdomen (1 patient), breast (1 patient), kidney (1 patient), lung (1 patient), and colon (1 patient). The maximum tolerated dose was not realized with a maximum dose of 1.6 mg/m{sup 2}. One case of dose-limiting toxicity was appreciated (grade 3 urosepsis) and felt to be unrelated to bortezomib. The most common grade 3 toxicity was lymphopenia (10 patients). Common grade 1 to 2 events included nausea (7 patients), infection without neutropenia (6 patients), diarrhea (5 patients), and fatigue (5 patients). Conclusions: The combination of palliative external beam radiation with concurrent weekly bortezomib therapy at a dose of 1.6 mg/m{sup 2} is well tolerated in patients with metastatic solid tumors. The maximum tolerated dose of once weekly bortezomib delivered concurrently with radiation therapy is greater than 1.6 mg/m{sup 2}.« less

Evaluation of temperature differences for paired stations of the U.S. Climate Reference Network

USGS Publications Warehouse

Gallo, K.P.

2005-01-01

Adjustments to data observed at pairs of climate stations have been recommended to remove the biases introduced by differences between the stations in time of observation, temperature instrumentatios, latitude, and elevation. A new network of climate stations, located in rural settings, permits comparisons of temperatures for several pairs of stations without two of the biases (time of observation and instrurtientation). The daily, monthly, and annual minimum, maximum, and mean temperatures were compared for five pairs of stations included in the U.S. Climate Reference Network. Significant differences were found between the paired stations in the annual minimum, maximum, and mean temperatures for all five pairs of stations. Adjustments for latitude and elevation differences contributed to greater differences in mean annual temperature for four of the five stations. Lapse rates computed from the mean annual temperature differences between station pairs differed from a constant value, whether or not latitude adjustments were made to the data. The results suggest that microclimate influences on temperatures observed at nearby (horizontally and vertically) stations are potentially much greater than influences that might be due to latitude or elevation differences between the stations. ?? 2005 American Meteorological Society.

An environmental dose experiment

NASA Astrophysics Data System (ADS)

Peralta, Luis

2017-11-01

Several radiation sources worldwide contribute to the delivered dose to the human population. This radiation also acts as a natural background when detecting radiation, for instance from radioactive sources. In this work a medium-sized plastic scintillation detector is used to evaluate the dose delivered by natural radiation sources. Calibration of the detector involved the use of radioactive sources and Monte Carlo simulation of the energy deposition per disintegration. A measurement of the annual dose due to background radiation to the body was then estimated. A dose value compatible with the value reported by the United Nations Scientific Committee on the Effects of Atomic Radiation was obtained.

Dose assessment of aircraft crew in The Netherlands.

PubMed

Van Dijk, J W E

2003-01-01

As the operator of the National Dose Registration and Information System, NRG has implemented a system for radiation exposure monitoring for the Dutch airlines. The system is based on the use of computer generated flight plans together with dose calculations using the CARI-6M program. Before installing the system a study was performed to estimate the uncertainty in the assessment of the annual dose of the crew members. It was concluded that the proposed system complies with international recommendations on the uncertainty in dose assessments in individual monitoring and that the operational costs of the system are low.

On the suitability of the copula types for the joint modelling of flood peaks and volumes along the Danube River

NASA Astrophysics Data System (ADS)

Kohnová, Silvia; Papaioannou, George; Bacigál, Tomáš; Szolgay, Ján; Hlavčová, Kamila; Loukas, Athanasios; Výleta, Roman

2017-04-01

Flood frequency analysis is often performed as a univariate analysis of flood peaks using a suitable theoretical probability distribution of the annual maximum flood peaks or peak over threshold values. However, also other flood attributes, such as flood volume and duration, are often necessary for the design of hydrotechnical structures and projects. In this study, the suitability of various copula families for a bivariate analysis of peak discharges and flood volumes has been tested on the streamflow data from gauging stations along the whole Danube River. Kendall's rank correlation coefficient (tau) quantifies the dependence between flood peak discharge and flood volume settings. The methodology is tested on two different data samples: 1) annual maximum flood (AMF) peaks with corresponding flood volumes, which is a typical choice for engineering studies and 2). annual maximum flood (AMF) peaks combined with annual maximum flow volumes of fixed durations at 5, 10, 15, 20, 25, 30 and 60 days, which can be regarded as a regime analysis of the dependence between the extremes of both variables in a given year. The bivariate modelling of the peak discharge - flood volume couples is achieved with the use of the the following copulas: Ali-Mikhail-Haq (AMH), Clayton, Frank, Joe, Gumbel, HuslerReiss, Galambos, Tawn, Normal, Plackett and FGM, respectively. Scatterplots of the observed and simulated peak discharge - flood volume pairs and goodness-of-fit tests have been used to assess the overall applicability of the copulas as well as observing any changes in suitable models along the Danube River. The results indicate that, almost all of the considered Archimedean class copulas (e.g. Frank, Clayton and Ali-Mikhail-Haq) perform better than the other copula families selected for this study, and that for the second data samples mostly the upper-tail-flat copulas were suitable.

40 CFR 464.43 - Effluent limitations guidelines representing the degree of effluent reduction attainable by the...

Code of Federal Regulations, 2011 CFR

2011-07-01

... (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS METAL MOLDING AND CASTING POINT SOURCE CATEGORY Zinc Casting... copper, lead, zinc, and total phenols. For non-continuous dischargers, annual average mass limitations....0187 Lead (T) 0.0237 0.0116 Zinc (T) 0.0339 0.0129 Maximum for any 1 day Maximum for monthly average...

40 CFR 464.43 - Effluent limitations guidelines representing the degree of effluent reduction attainable by the...

Code of Federal Regulations, 2010 CFR

2010-07-01

... (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS METAL MOLDING AND CASTING POINT SOURCE CATEGORY Zinc Casting... copper, lead, zinc, and total phenols. For non-continuous dischargers, annual average mass limitations....0187 Lead (T) 0.0237 0.0116 Zinc (T) 0.0339 0.0129 Maximum for any 1 day Maximum for monthly average...

Hydrologic and climatic changes in three small watersheds after timber harvest.

Treesearch

W.B. Fowler; J.D. Helvey; E.N. Felix

1987-01-01

No significant increases in annual water yield were shown for three small watersheds in northeastern Oregon after shelterwood cutting (30-percent canopy removal, 50-percent basal area removal) and clearcutting. Average maximum air temperature increased after harvest and average minimum air temperature decreased by up to 2.6 °C. Both maximum and minimum water...

77 FR 47318 - Fisheries Off West Coast States; Coastal Pelagic Species Fisheries; Annual Specifications

Federal Register 2010, 2011, 2012, 2013, 2014

2012-08-08

... (CPS) Fishery Management Plan (FMP). The 2012 maximum HG for Pacific sardine is 109,409 metric tons (mt... framework in the FMP. This framework includes a harvest control rule that determines the maximum HG, the... 109,409 metric tons (mt) for the 2012 Pacific sardine fishing year. These catch specifications are...

A rule of unity for human intestinal absorption 3: Application to pharmaceuticals.

PubMed

Patel, Raj B; Yalkowsky, Samuel H

2018-02-01

The rule of unity is based on a simple absorption parameter, Π, that can accurately predict whether or not an orally administered drug will be well absorbed or poorly absorbed. The intrinsic aqueous solubility and octanol-water partition coefficient, along with the drug dose are used to calculate Π. We show that a single delineator value for Π exist that can distinguish whether a drug is likely to be well absorbed (FA ≥ 0.5) or poorly absorbed (FA < 0.5) at any specified dose. The model is shown to give 82.5% correct predictions for over 938 pharmaceuticals. The maximum well-absorbed dose (i.e. the maximum dose that will be more than 50% absorbed) calculated using this model can be utilized as a guideline for drug design and synthesis. Copyright © 2017 John Wiley & Sons, Ltd.

Commissioning dosimetry and in situ dose mapping of a semi-industrial Cobalt-60 gamma-irradiation facility using Fricke and Ceric-cerous dosimetry system and comparison with Monte Carlo simulation data

NASA Astrophysics Data System (ADS)

Mortuza, Md Firoz; Lepore, Luigi; Khedkar, Kalpana; Thangam, Saravanan; Nahar, Arifatun; Jamil, Hossen Mohammad; Bandi, Laxminarayan; Alam, Md Khorshed

2018-03-01

Characterization of a 90 kCi (3330 TBq), semi-industrial, cobalt-60 gamma irradiator was performed by commissioning dosimetry and in-situ dose mapping experiments with Ceric-cerous and Fricke dosimetry systems. Commissioning dosimetry was carried out to determine dose distribution pattern of absorbed dose in the irradiation cell and products. To determine maximum and minimum absorbed dose, overdose ratio and dwell time of the tote boxes, homogeneous dummy product (rice husk) with a bulk density of 0.13 g/cm3 were used in the box positions of irradiation chamber. The regions of minimum absorbed dose of the tote boxes were observed in the lower zones of middle plane and maximum absorbed doses were found in the middle position of front plane. Moreover, as a part of dose mapping, dose rates in the wall positions and some selective strategic positions were also measured to carry out multiple irradiation program simultaneously, especially for low dose research irradiation program. In most of the cases, Monte Carlo simulation data, using Monte Carlo N-Particle eXtended code version MCNPX 2.7., were found to be in congruence with experimental values obtained from Ceric-cerous and Fricke dosimetry; however, in close proximity positions from the source, the dose rate variation between chemical dosimetry and MCNP was higher than distant positions.

Dosimetric comparison between VMAT with different dose calculation algorithms and protons for soft-tissue sarcoma radiotherapy.

PubMed

Fogliata, Antonella; Scorsetti, Marta; Navarria, Piera; Catalano, Maddalena; Clivio, Alessandro; Cozzi, Luca; Lobefalo, Francesca; Nicolini, Giorgia; Palumbo, Valentina; Pellegrini, Chiara; Reggiori, Giacomo; Roggio, Antonella; Vanetti, Eugenio; Alongi, Filippo; Pentimalli, Sara; Mancosu, Pietro

2013-04-01

To appraise the potential of volumetric modulated arc therapy (VMAT, RapidArc) and proton beams to simultaneously achieve target coverage and enhanced sparing of bone tissue in the treatment of soft-tissue sarcoma with adequate target coverage. Ten patients presenting with soft-tissue sarcoma of the leg were collected for the study. Dose was prescribed to 66.5 Gy in 25 fractions to the planning target volume (PTV) while significant maximum dose to the bone was constrained to 50 Gy. Plans were optimised according to the RapidArc technique with 6 MV photon beams or for intensity modulated protons. RapidArc photon plans were computed with: 1) AAA; 2) Acuros XB as dose to medium; and 3) Acuros XB as dose to water. All plans acceptably met the criteria of target coverage (V95% >90-95%) and bone sparing (D(1 cm3) <50 Gy). Significantly higher PTV dose homogeneity was found for proton plans. Near-to-maximum dose to bone was similar for RapidArc and protons, while volume receiving medium/low dose levels was minimised with protons. Similar results were obtained for the remaining normal tissue. Dose distributions calculated with the dose to water option resulted ~5% higher than corresponding ones computed as dose to medium. High plan quality was demonstrated for both VMAT and proton techniques when applied to soft-tissue sarcoma.

Relation of gastric acid and pepsin secretion to serum gastrin levels in dogs given bombesin and gastrin-17.

PubMed

Hirschowitz, B I; Molina, E

1983-05-01

To quantitate bombesin stimulation of gastric acid and pepsin via release of gastrin, five gastric fistula dogs were given graded doses (60-1,250 pmol X kg-1 X h-1) of bombesin tetradecapeptide and 40-2,000 pmol X kg-1 X h-1 of synthetic gastrin-17 (G-17). Acid and pepsin output and serum gastrin were proportional to the dose of stimulant. The half-maximal dose of bombesin for gastrin release was 200 pmol X kg-1 X h-1. Bombesin-stimulated acid secretion related to serum gastrin concentrations was congruent with the G-17 curve, but with a maximum of only 62% of the G-17 maximum before declining by 27% despite higher serum gastrin levels. This suggested that bombesin stimulates acid secretion only via gastrin release and inhibits at higher doses by releasing another inhibitory peptide, most likely somatostatin, which is also released by bombesin. The same mechanism could apply to supramaximal inhibition of acid and pepsin seen with high doses of G-17. Because the pepsin curve related to serum gastrin was to the left of the G-17 curve, we concluded that another secretagogue released by bombesin acts synergistically with gastrin on pepsin secretion. Therefore, bombesin stimulates gastric secretion through gastrin release, but its effects are modified by peptides coreleased to a) increase pepsin output at low doses and b) limit the output of acid and pepsin to 50-60% of the G-17 maximum.

The composition of bulk precipitation on a coastal island with agriculture compared to an urban region

NASA Astrophysics Data System (ADS)

Weijers, E. P.; Vugts, H. F.

Results of chemical analyses of monthly bulk samples from Schiermonnikoog, one of the islands in the northern part of The Netherlands, are interpreted. The continuous record covers a period of more than 15 years. A comparison (10 years) is made with Ouderkerk, a village near Amsterdam. Non-sea salt contributions, relations between ion species, long-time trends, annual cycles and meteorological influence are discussed. The study reveals enhanced levels of ammonium in the Schiermonnikoog samples with respect to Ouderkerk. Also, concentrations of sulfate and nitrate were higher. The high concentrations of ammonium are ascribed to dry-deposited NH 3 caused by cattle breeding, the only economical activity on the island. A significant positive trend reflects its intensifying nature. Annual cycles and statistical computations indicate prior combination of parts of ammonium and excess sulfate as ammonium sulfate. The nitrate content appears to be strongly related to ammonium ( r = 079). In the Ouderkerk dataset this correspondence is much weaker (0.37), whereas its pH values are systematically lower. It is therefore believed that on Schiermonnikoog concentrations of nitrate are increased by nitrification of ammonium in the collector. Annual cycles of sodium, magnesium and chloride, and to a lesser extent potassium, are very similar (maximum concentrations in November, December and January, and a relative maximum in April). The other annual patterns peak in the first half of the year: maximum concentrations are found in February (ammonium, excess sulfate), June (nitrate), January (potassium) and in April (excess calcium). A combination of frequently occurring offshore winds and low precipitation amounts will account for this behavior.

Global Analysis of Empirical Relationships Between Annual Climate and Seasonality of NDVI

NASA Technical Reports Server (NTRS)

Potter, C. S.

1997-01-01

This study describes the use of satellite data to calibrate a new climate-vegetation greenness function for global change studies. We examined statistical relationships between annual climate indexes (temperature, precipitation, and surface radiation) and seasonal attributes of the AVHRR Normalized Difference Vegetation Index (NDVI) time series for the mid-1980s in order to refine our empirical understanding of intraannual patterns and global abiotic controls on natural vegetation dynamics. Multiple linear regression results using global l(sup o) gridded data sets suggest that three climate indexes: growing degree days, annual precipitation total, and an annual moisture index together can account to 70-80 percent of the variation in the NDVI seasonal extremes (maximum and minimum values) for the calibration year 1984. Inclusion of the same climate index values from the previous year explained no significant additional portion of the global scale variation in NDVI seasonal extremes. The monthly timing of NDVI extremes was closely associated with seasonal patterns in maximum and minimum temperature and rainfall, with lag times of 1 to 2 months. We separated well-drained areas from l(sup o) grid cells mapped as greater than 25 percent inundated coverage for estimation of both the magnitude and timing of seasonal NDVI maximum values. Predicted monthly NDVI, derived from our climate-based regression equations and Fourier smoothing algorithms, shows good agreement with observed NDVI at a series of ecosystem test locations from around the globe. Regions in which NDVI seasonal extremes were not accurately predicted are mainly high latitude ecosystems and other remote locations where climate station data are sparse.

The Eocene climate of China, the early elevation of the Tibetan Plateau and the onset of the Asian Monsoon.

PubMed

Wang, Qing; Spicer, Robert A; Yang, Jian; Wang, Yu-Fei; Li, Cheng-Sen

2013-12-01

Eocene palynological samples from 37 widely distributed sites across China were analysed using co-existence approach to determine trends in space and time for seven palaeoclimate variables: Mean annual temperature, mean annual precipitation, mean temperature of the warmest month, mean temperature of the coldest month, mean annual range of temperature, mean maximum monthly precipitation and mean minimum monthly precipitation. Present day distributions and observed climates within China of the nearest living relatives of the fossil forms were used to find the range of a given variable in which a maximum number of taxa can coexist. Isotherm and isohyet maps for the early, middle and late Eocene were constructed. These illustrate regional changing patterns in thermal and precipitational gradients that may be interpreted as the beginnings of the modern Asian Monsoon system, and suggest that the uplift of parts of the Tibetan Plateau appear to have taken place by the middle to late Eocene. © 2013 John Wiley & Sons Ltd.

Spatial distribution of temperature trends and extremes over Maharashtra and Karnataka States of India

NASA Astrophysics Data System (ADS)

Dhorde, Amit G.; Korade, Mahendra S.; Dhorde, Anargha A.

2017-10-01

Earth surface temperatures are changing worldwide together with the changes in the extreme temperatures. The present study investigates trends and variations of monthly maximum and minimum temperatures and their effects on seasonal fluctuations at different climatological stations of Maharashtra and Karnataka states of India. Trend analysis was performed on annual and seasonal mean maximum temperature (TMAX) and mean minimum temperature (TMIN) for the period 1969 to 2006. During the last 38 years, an increase in annual TMAX and TMIN has occurred. At most of the locations, the increase in TMAX was faster than the TMIN, resulting in an increase in diurnal temperature range. At the same time, annual mean temperature (TM) showed a significant increase over the study area. Percentiles were used to identify extreme temperature indices. An increase in occurrence of warm extremes was observed at southern locations, and cold extremes increased over the central and northeastern part of the study area. Occurrences of cold wave conditions have decreased rapidly compared to heat wave conditions.