WorldWideScience

Sample records for iodine model addition

  1. Primary circuit iodine model addition to IMPAIR-3

    Energy Technology Data Exchange (ETDEWEB)

    Osetek, D.J.; Louie, D.L.Y. [Los Alamos Technical Associates, Inc., Albuquerque, NM (United States); Guntay, S.; Cripps, R. [Paul Scherrer Inst. (PSI), Villigen (Switzerland)

    1996-12-01

    As part of a continuing effort to provide the U.S. Department of Energy (DOE) Advanced Reactor Severe Accident Program (ARSAP) with complete iodine analysis capability, a task was undertaken to expand the modeling of IMPAIR-3, an iodine chemistry code. The expanded code will enable the DOE to include detailed iodine behavior in the assessment of severe accident source terms used in the licensing of U.S. Advanced Light Water Reactors (ALWRs). IMPAIR-3 was developed at the Paul Scherrer Institute (PSI), Switzerland, and has been used by ARSAP for the past two years to analyze containment iodine chemistry for ALWR source term analyses. IMPAIR-3 is primarily a containment code but the iodine chemistry inside the primary circuit (the Reactor Coolant System or RCS) may influence the iodine species released into the the containment; therefore, a RCS iodine chemistry model must be implemented in IMPAIR-3 to ensure thorough source term analysis. The ARSAP source term team and the PSI IMPAIR-3 developers are working together to accomplish this task. This cooperation is divided into two phases. Phase I, taking place in 1996, involves developing a stand-alone RCS iodine chemistry program called IMPRCS (IMPAIR -Reactor Coolant System). This program models a number of the chemical and physical processes of iodine that are thought to be important at conditions of high temperature and pressure in the RCS. In Phase II, which is tentatively scheduled for 1997, IMPRCS will be implemented as a subroutine in IMPAIR-3. To ensure an efficient calculation, an interface/tracking system will be developed to control the use of the RCS model from the containment model. These two models will be interfaced in such a way that once the iodine is released from the RCS, it will no longer be tracked by the RCS model but will be tracked by the containment model. All RCS thermal-hydraulic parameters will be provided by other codes. (author) figs., tabs., refs.

  2. The addition of iodine to tetramethylammonium iodide

    Science.gov (United States)

    Foote, H.W.; Fleischer, M.

    1953-01-01

    The system tetramethylammonium iodide-iodine-toluene has been studied by the solubility method at 6 and at 25??. The compounds (CH3)4NI3, (CH3)4NI5 and (CH3)4NI11 were found to be stable phases at both temperatures. In addition, the compound (CH3)4NI10 was found at 6?? and the compound (CH3)4NI9 at 25??. The dissociation pressures of the compounds at these temperatures were calculated from the solubility data.

  3. FDA regulations regarding iodine addition to foods and labeling of foods containing added iodine.

    Science.gov (United States)

    Trumbo, Paula R

    2016-09-01

    The US Food and Drug Administration (FDA) regulates the addition of iodine to infant formulas, the iodization of salt, and the addition of salt and iodine to foods. The required amount of iodine in infant formulas is based on caloric content, and the label must provide the iodine content per 100 kcal. Cuprous iodide and potassium iodide may be added to table salt as a source of dietary iodine at a maximum amount of 0.01%; if added, the label must indicate that the salt is iodized. Table salt to which iodine has not been added must bear the statement, "This salt does not supply iodide, a necessary nutrient." If a nutrient is to be appropriately added to a food for the purpose of correcting a dietary insufficiency, there should be sufficient scientific information available to demonstrate a nutritional deficiency and/or identify a public health problem. Furthermore, the population groups that would benefit from the proposed fortification should be identified. If iodine is added to a food, the percent Daily Value of iodine must be listed. There are no FDA regulations governing ingredient standards for dietary supplements. As a result, some dietary supplements include iodine and others do not. If a supplement contains iodine, the Supplement Facts label must list iodine as a nutrient ingredient. If iodine is not listed on the Supplement Facts label, then it has not been added. There are similarities between the FDA, which establishes US food regulations and policies, and the Codex Alimentarius (Codex), which develops international food standards and guidelines under the aegis of the FAO and the WHO. Both the FDA and Codex call for the labeling of table salt to indicate fortification with iodine, voluntary labeling of iodine on foods, and a Daily Value (called a Nutrient Reference Value by Codex) of 150 μg for iodine.

  4. A model to secure a stable iodine concentration in milk

    Directory of Open Access Journals (Sweden)

    Gisken Trøan

    2015-12-01

    Full Text Available Background: Dairy products account for approximately 60% of the iodine intake in the Norwegian population. The iodine concentration in cow's milk varies considerably, depending on feeding practices, season, and amount of iodine and rapeseed products in cow fodder. The variation in iodine in milk affects the risk of iodine deficiency or excess in the population. Objective: The first goal of this study was to develop a model to predict the iodine concentration in milk based on the concentration of iodine and rapeseed or glucosinolate in feed, as a tool to securing stable iodine concentration in milk. A second aim was to estimate the impact of different iodine levels in milk on iodine nutrition in the Norwegian population. Design: Two models were developed on the basis of results from eight published and two unpublished studies from the past 20 years. The models were based on different iodine concentrations in the fodder combined with either glucosinolate (Model 1 or rapeseed cake/meal (Model 2. To illustrate the impact of different iodine concentrations in milk on iodine intake, we simulated the iodine contribution from dairy products in different population groups based on food intake data in the most recent dietary surveys in Norway. Results: The models developed could predict iodine concentration in milk. Cross-validation showed good fit and confirmed the explanatory power of the models. Our calculations showed that dairy products with current iodine level in milk (200 µg/kg cover 68, 49, 108 and 56% of the daily iodine requirements for men, women, 2-year-old children, and pregnant women, respectively. Conclusions: Securing a stable level of iodine in milk by adjusting iodine concentration in different cow feeds is thus important for preventing excess intake in small children and iodine deficiency in pregnant and non-pregnant women.

  5. Theoretical Studies on the Iodine-catalyzed Nucleophilic Addition of Acetone with Five-membered Heterocycles

    Institute of Scientific and Technical Information of China (English)

    WANG Yan-hua; LI Li; CHEN Xue-song

    2008-01-01

    The iodine-catalyzed nucleophilic addition reactions of pyrrole,furan,or thiophene with acetone were studied in gas and solvent by the density functional theory at the level of Lan12DZ*,It was seen that the halogen bond between iodine and carbonyl oxygen appeared to have an important catalytic effect on such reactions,and the first iodine molecule maximally diminished the barrier height by 41 kJ/mol,while the second iodine molecule could not improve such reactions largely,It was concluded that the C2-addition was generally more favorable than the C3-addition for the three heterocycles;however,iodine considerably more effectively catalyzed the C3-addition than the C2-addition for pyrrole,It was also revealed by PCM calculation that the iodine-catalyzed nucleophilic additions occurred more easily in solvent than in gas,which explained the experiment performed by Bandgar et al..

  6. Work of the Polish Council for Control of Iodine Deficiency Disorders, and the model of iodine prophylaxis in Poland.

    Science.gov (United States)

    Szybiński, Zbigniew

    2012-01-01

    The Polish Council for Control of Iodine Deficiency Disorders (PCCIDD) was established in 1991 in Krakow at the Chair and Dept. of Endocrinology, Jagiellonian University, Collegium Medicum, following the example of the International Council for Control of Iodine Deficiency Disorders (ICCIDD) in Charlottesville, USA. The PCCIDD co-operates with the European Co-ordinating Centre in Pisa, Italy. The PCCIDD comprises a group of experts in endocrinology, iodine prophylaxis, the technology of salt and food iodisation, and Polish representatives of several organisations: WHO, UNICEF, the Polish Consumers Federation, and the Spokesman for Children's Rights. The strategic goal of the Polish Council is to solve the problem of iodine deficiency in Poland realising the Programme for Elimination of Iodine Deficiency financed by the Ministry of Health. The Polish model of iodine prophylaxis contains obligatory iodisation of household salt (20-40 mg KI/1 kg) and neonates' formula (10 μg/100 mL of milk), and additional supplementation for pregnant and breastfeeding women with 150-200 μg of iodine as pharmacotherapy. The model is very effective: endemic goitre in schoolchildren has been eradicated, the prevalence of goitre in pregnant women has fallen from 80% to 19%, the frequency of transient hypothyroidism in neonates has dropped from 2.0% to 0.16%, and the observed increase of incidence rate of thyroid cancer in women over 40 years old has diminished markedly. In 2008, a WHO Collaborating Centre (WHOCC) for Nutrition was designated at the Department of Endocrinology, UJCM in Krakow. The main goal of the WHOCC is to sustain effective iodine prophylaxis in Poland in the light of the latest WHO recommendations on the necessary reduction of daily salt intake as a risk factor for hypertension and arteriosclerosis. Therefore, additional standardised carriers of iodine (milk, mineral water) have been introduced into the food market.

  7. Models of iodine behavior in reactor containments

    Energy Technology Data Exchange (ETDEWEB)

    Weber, C.F.; Beahm, E.C.; Kress, T.S.

    1992-10-01

    Models are developed for many phenomena of interest concerning iodine behavior in reactor containments during severe accidents. Processes include speciation in both gas and liquid phases, reactions with surfaces, airborne aerosols, and other materials, and gas-liquid interface behavior. Although some models are largely empirical formulations, every effort has been made to construct mechanistic and rigorous descriptions of relevant chemical processes. All are based on actual experimental data generated at the Oak Ridge National Laboratory (ORNL) or elsewhere, and, hence, considerable data evaluation and parameter estimation are contained in this study. No application or encoding is attempted, but each model is stated in terms of rate processes, with the intention of allowing mechanistic simulation. Taken together, this collection of models represents a best estimate iodine behavior and transport in reactor accidents.

  8. Iodine

    Science.gov (United States)

    ... applied inside the mouth to treat gum disease (periodontitis) and reduce bleeding after the removal of a ... the medications erythromycin or chloramphenicol. Foot ulcers in diabetes. Applying iodine to foot ulcers might be beneficial ...

  9. Theoretical Study of the Iodine-catalyzed Nucleophilic Addition by Halogen Bond

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The iodine-catalyzed nucleophilic addition of pyrrole to acetone has been studied by density functional theory at the level of Lanl2DZ*. It has been shown that the first iodine molecule appears to have a remarkable catalytic effect on this reaction by halogen bond between carbonyl oxygen and iodine molecule, but the second one does not improve the reaction largely. In general, the nucleophilic addition at the C(2) site of pyrrole is more favorable than that at the C(3)site;however, this trend is not prominent or even changed in acetronitrile solvent for the indole system, which is consistent with the experimental result by Bandgar.

  10. Pool scrubbing models for iodine components

    Energy Technology Data Exchange (ETDEWEB)

    Fischer, K. [Battelle Ingenieurtechnik GmbH, Eschborn (Germany)

    1996-12-01

    Pool scrubbing is an important mechanism to retain radioactive fission products from being carried into the containment atmosphere or into the secondary piping system. A number of models and computer codes has been developed to predict the retention of aerosols and fission product vapours that are released from the core and injected into water pools of BWR and PWR type reactors during severe accidents. Important codes in this field are BUSCA, SPARC and SUPRA. The present paper summarizes the models for scrubbing of gaseous Iodine components in these codes, discusses the experimental validation, and gives an assessment of the state of knowledge reached and the open questions which persist. The retention of gaseous Iodine components is modelled by the various codes in a very heterogeneous manner. Differences show up in the chemical species considered, the treatment of mass transfer boundary layers on the gaseous and liquid sides, the gas-liquid interface geometry, calculation of equilibrium concentrations and numerical procedures. Especially important is the determination of the pool water pH value. This value is affected by basic aerosols deposited in the water, e.g. Cesium and Rubidium compounds. A consistent model requires a mass balance of these compounds in the pool, thus effectively coupling the pool scrubbing phenomena of aerosols and gaseous Iodine species. Since the water pool conditions are also affected by drainage flow of condensate water from different regions in the containment, and desorption of dissolved gases on the pool surface is determined by the gas concentrations above the pool, some basic limitations of specialized pool scrubbing codes are given. The paper draws conclusions about the necessity of coupling between containment thermal-hydraulics and pool scrubbing models, and proposes ways of further simulation model development in order to improve source term predictions. (author) 2 tabs., refs.

  11. Simulation model accurately estimates total dietary iodine intake.

    Science.gov (United States)

    Verkaik-Kloosterman, Janneke; van 't Veer, Pieter; Ocké, Marga C

    2009-07-01

    One problem with estimating iodine intake is the lack of detailed data about the discretionary use of iodized kitchen salt and iodization of industrially processed foods. To be able to take into account these uncertainties in estimating iodine intake, a simulation model combining deterministic and probabilistic techniques was developed. Data from the Dutch National Food Consumption Survey (1997-1998) and an update of the Food Composition database were used to simulate 3 different scenarios: Dutch iodine legislation until July 2008, Dutch iodine legislation after July 2008, and a potential future situation. Results from studies measuring iodine excretion during the former legislation are comparable with the iodine intakes estimated with our model. For both former and current legislation, iodine intake was adequate for a large part of the Dutch population, but some young children (iodine levels, the percentage of the Dutch population with intakes that were too low increased (almost 10% of young children). To keep iodine intakes adequate, salt iodine levels should not be decreased, unless many more foods will contain iodized salt. Our model should be useful in predicting the effects of food reformulation or fortification on habitual nutrient intakes.

  12. Crystal Sinking Modeling for Designing Iodine Crystallizer in Thermochemical Sulfur-Iodine Hydrogen Production Process

    Energy Technology Data Exchange (ETDEWEB)

    Park, Byung Heung [Korea National University of Transportation, Chungju (Korea, Republic of); Jeong, Seong-Uk [Korea Institute of Energy Research, Daejeon (Korea, Republic of); Kang, Jeong Won [Korea University, Seoul (Korea, Republic of)

    2014-12-15

    SI process is a thermochemical process producing hydrogen by decomposing water while recycling sulfur and iodine. Various technologies have been developed to improve the efficiency on Section III of SI process, where iodine is separated and recycled. EED(electro-electrodialysis) could increase the efficiency of Section III without additional chemical compounds but a substantial amount of I{sub 2} from a process stream is loaded on EED. In order to reduce the load, a crystallization technology prior to EED is considered as an I{sub 2} removal process. In this work, I{sub 2} particle sinking behavior was modeled to secure basic data for designing an I{sub 2} crystallizer applied to I{sub 2}-saturated HI{sub x} solutions. The composition of HI{sub x} solution was determined by thermodynamic UVa model and correlation equations and pure properties were used to evaluate the solution properties. A multiphysics computational tool was utilized to calculate particle sinking velocity changes with respect to I{sub 2} particle radius and temperature. The terminal velocity of an I{sub 2} particle was estimated around 0.5 m/s under considered radius (1.0 to 2.5 mm) and temperature (10 to 50 .deg. C) ranges and it was analyzed that the velocity is more dependent on the solution density than the solution viscosity.

  13. Simulation model accurately estimates total dietary iodine intake

    NARCIS (Netherlands)

    Verkaik-Kloosterman, J.; Veer, van 't P.; Ocke, M.C.

    2009-01-01

    One problem with estimating iodine intake is the lack of detailed data about the discretionary use of iodized kitchen salt and iodization of industrially processed foods. To be able to take into account these uncertainties in estimating iodine intake, a simulation model combining deterministic and p

  14. Modelling iodine behaviour using LIRIC 3.0

    Energy Technology Data Exchange (ETDEWEB)

    Wren, J.C.; Glowa, G.A.; Ball, J.M. [Atomic Energy of Canada Ltd., Pinawa, MB (Canada). Whiteshell Labs.

    1996-12-01

    The overall objective of the iodine chemistry research program at the Whiteshell Laboratories of AECL is to develop and validate the LIRIC (Library of Iodine Reactions In Containment) model. The model, once validated, is intended as either a stand-alone analytical tool or for incorporation into a code for licensing analyses of fission-product behaviour in containment. LIRIC is currently being used to assess the role and importance of individual phenomena on iodine volatility under reactor accident conditions and, thus, help to establish priorities within the iodine research program. The LIRIC model has undergone significant alterations since it was last reported (LIRIC 2.0), mainly as a result of considerable development in understanding of iodine behaviour over the last few years. The new version, LIRIC 3.0, has been used to simulate various results from the Radioiodine Test Facility (RTF) with reasonable success, although under somewhat limited conditions.

  15. Determine Minimum Silver Flake Addition to GCM for Iodine Loaded AgZ

    Energy Technology Data Exchange (ETDEWEB)

    Garino, Terry J.; Nenoff, Tina M.; Rodriguez, Mark A.

    2014-04-01

    The minimum amount of silver flake required to prevent loss of I{sub 2} during sintering in air for a SNL Glass Composite Material (GCM) Waste Form containing AgI-MOR (ORNL, 8.7 wt%) was determined to be 1.1 wt% Ag. The final GCM composition prior to sintering was 20 wt% AgI-MOR, 1.1 wt% Ag, and 80 wt% Bi-Si oxide glass. The amount of silver flake needed to suppress iodine loss was determined using thermo gravimetric analysis with mass spectroscopic off-gas analysis. These studies found that the ratio of silver to AgI-MOR required is lower in the presence of the glass than without it. Therefore an additional benefit of the GCM is that it serves to inhibit some iodine loss during processing. Alternatively, heating the AgI-MOR in inert atmosphere instead of air allowed for densified GCM formation without I{sub 2} loss, and no necessity for the addition of Ag. The cause of this behavior is found to be related to the oxidation of the metallic Ag to Ag{sup +} when heated to above ~300{degrees}C in air. Heating rate, iodine loading levels and atmosphere are the important variables that determine AgI migration and results suggest that AgI may be completely incorporated into the mordenite structure by the 550{degrees}C sintering temperature.

  16. Evaluation of the pool chemistry model in MELCOR by considering the organic iodine formation within the pool using the phebus FPT-1 test data

    Energy Technology Data Exchange (ETDEWEB)

    Park, Jong Hwa; Kim, Dong Ha [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)

    2004-07-01

    temperature and concentration of iodine. Generally, it showed that the high PH value could prevent the formation of volatile iodine. Therefore the addition of silver into the pool and the control of PH at high value are another important parameters for the iodine management strategy. In this study, the pool chemistry within the sump of Phebus FPT-1 was simulated with MELCOR1.8.5. The purpose of this study is to evaluate the status of current pool chemistry model in MELCOR. The description on the input data and some assumptions will be given in section 2. Also, the evaluation results and the main findings on the pool chemistry model in MELCOR will be shown in conclusion as a summary form.

  17. Global model of an iodine gridded plasma thruster

    Science.gov (United States)

    Grondein, P.; Lafleur, T.; Chabert, P.; Aanesland, A.

    2016-03-01

    Most state-of-the-art electric space propulsion systems such as gridded and Hall effect thrusters use xenon as the propellant gas. However, xenon is very rare, expensive to produce, and used in a number of competing industrial applications. Alternatives to xenon are currently being investigated, and iodine has emerged as a potential candidate. Its lower cost and larger availability, its solid state at standard temperature and pressure, its low vapour pressure and its low ionization potential make it an attractive option. In this work, we compare the performances of a gridded ion thruster operating separately with iodine and xenon, under otherwise identical conditions using a global model. The thruster discharge properties such as neutral, ion, and electron densities and electron temperature are calculated, as well as the thruster performance parameters such as thrust, specific impulse, and system efficiencies. For similar operating conditions, representative of realistic thrusters, the model predicts similar thrust levels and performances for both iodine and xenon. The thruster efficiency is however slightly higher for iodine compared with xenon, due to its lower ionization potential. This demonstrates that iodine could be a viable alternative propellant for gridded plasma thrusters.

  18. Excessive additive iodine intake reduces sperm production and induces sperm deformity in male rats in early development

    Institute of Scientific and Technical Information of China (English)

    Zhang Shu-Cheng; He Bin; Wang Ning; Ren Tong-Tong; Wang ShangMing; Zhang Chang-Yong; Chen Xi-Hua; Wang Jie-Dong

    2011-01-01

    Objective:To investigate the effect of excessive additive iodine intake on reproductive organs of male weanling rats.Methods:One hundred and three male weanling rats were fed with feedstuff containing 0,0.5,1,2.5,and 5-fold higher dosage of iodine in standard iodine-additive salt,i,e.200,300,400,700,and 1200 μg/kg,respectively,for 130-136 days.The number of rats taking different dosages of iodine was 20,21,21,21,20 respectively.The rats fed 200μg/kg of iodine were taken as the control group.For all groups,their structural changes of reproductive organs and sperm quality were evaluated.Results:The three experiment groups fed with 1,2.5,and 5-fold higher dosage iodine showed apparent reduction in testicular weight (P<0.05-0.01) by 10.76%,14.58% and 25.35%,respectively,compared with the control.But significant reduction in testis/body weight ratio was only observed in the 5-fold higher dosage group.The sperm concentration and total sperm count declined in four experiment groups fed with 0.5-5 fold higher dosage of iodine.The sperm concentration was reduced by 6.59%,22.53%,17.35% and 18.06% respectively.The percentage of sperm with normal and abnormal form significantly changed (P<0.05).The addition of different doses of iodine showed no apparent adverse effects on other reproductive organs or sperm viability.Conclution:These results indicated that excessive iodine intake might cause potential hazards on reproductive organs of male rats with respect to spermatogenesis.

  19. Modelling protection behaviour towards micronutrient deficiencies: Case of iodine biofortified vegetable legumes as health intervention for school-going children

    Science.gov (United States)

    De Steur, Hans; Gellynck, Xavier; Makokha, Anselimo

    2016-01-01

    BACKGROUND/OBJECTIVES Despite successes recorded in combating iodine deficiency, more than 2 billion people are still at risk of iodine deficiency disorders. Rural landlocked and mountainous areas of developing countries are the hardest hit, hence the need to explore and advance novel strategies such as biofortification. SUBJECTS/METHODS We evaluated adoption, purchase, and consumption of iodine biofortified vegetable legumes (IBVL) using the theory of protection motivations (PMT) integrated with an economic valuation technique. A total of 1,200 participants from three land-locked locations in East Africa were recruited via multi-stage cluster sampling, and data were collected using two, slightly distinct, questionnaires incorporating PMT constructs. The survey also elicited preferences for iodine biofortified foods when offered at a premium or discount. Determinants of protection motivations and preferences for iodine biofortified foods were assessed using path analysis modelling and two-limit Tobit regression, respectively. RESULTS Knowledge of iodine, iodine-health link, salt iodization, and biofortification was very low, albeit lower at the household level. Iodine and biofortification were not recognized as nutrient and novel approaches, respectively. On the other hand, severity, fear, occupation, knowledge, iodine status, household composition, and self-efficacy predicted the intention to consume biofortified foods at the household level; only vulnerability, self-efficacy, and location were the most crucial elements at the school level. In addition, results demonstrated a positive willingness-to-pay a premium or acceptance of a lesser discount for biofortification. Furthermore, preference towards iodine biofortified foods was a function of protection motivations, severity, vulnerability, fear, response efficacy, response cost, knowledge, iodine status, gender, age. and household head. CONCLUSIONS Results lend support for prevention of iodine deficiency in

  20. Conceptual Model of Iodine Behavior in the Subsurface at the Hanford Site

    Energy Technology Data Exchange (ETDEWEB)

    Truex, Michael J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Lee, Brady D. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Johnson, Christian D. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Qafoku, Nikolla P. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Last, George V. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Lee, Michelle H. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Kaplan, Daniel I. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2015-09-01

    The fate and transport of 129I in the environment and potential remediation technologies are currently being studied as part of environmental remediation activities at the Hanford Site. A conceptual model describing the nature and extent of subsurface contamination, factors that control plume behavior, and factors relevant to potential remediation processes is needed to support environmental remedy decisions. Because 129I is an uncommon contaminant, relevant remediation experience and scientific literature are limited. Thus, the conceptual model also needs to both describe known contaminant and biogeochemical process information and to identify aspects about which additional information needed to effectively support remedy decisions. this document summarizes the conceptual model of iodine behavior relevant to iodine in the subsurface environment at the Hanford site.

  1. Iodine-catalyzed addition of 2-mercaptoethanol to chalcone derivatives: Synthesis of the novel β-mercapto carbonyl compounds

    Directory of Open Access Journals (Sweden)

    Gürkan Yerli

    2012-01-01

    Full Text Available In this study, a series of novel β-mercapto carbonyl derivatives (3-(2-hydroxyethylthio-1,3-diarylpropan-1-one (5a-i were prepared by addition of 2-mercaptoethanol (4 to chalcones (3a-i in the presence of catalytic amount of iodine (10 mol % in CH 2Cl 2.

  2. Modeling of iodine radiation chemistry in the presence of organic compounds

    Energy Technology Data Exchange (ETDEWEB)

    Taghipour, Fariborz; Evans, Greg J. E-mail: evansg@chem-eng.toronto.edu

    2002-06-01

    A kinetic-based model was developed that simulates the radiation chemistry of iodine in the presence of organic compounds. The model's mechanistic description of iodine chemistry and generic semi-mechanistic reactions for various classes of organics, provided a reasonable representation of experimental results. The majority of the model and experimental results of iodine volatilization rates were in agreement within an order of magnitude.

  3. Modeling the discharge behavior of the lithium/iodine battery

    Energy Technology Data Exchange (ETDEWEB)

    Skarstad, P.M. (Medtronic, Inc., Minneapolis, MN (United States)); Schmidt, C.L. (Medtronic, Inc., Minneapolis, MN (United States))

    1993-03-15

    We have previously reported the development of a physically-based mode describing the discharge behaviour of the lithium/iodine battery. Values for the parameters of the model have been determined through analysis of discharge data from a wide variety of battery designs. This paper reviews the essential features of the model and describes several applications. These applications include estimation of performance distributions through Monte-Carlo simulations, analysis of variability in discharge performances, and identification of the parameters to which discharge performance is most sensitive. (orig.)

  4. RAIM-A model for iodine behavior in containment under severe accident condition

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Han Chul; Cho, Yeong Hun [Korea Institute of Nuclear Safety, Daejeon (Korea, Republic of)

    2015-12-15

    Following a severe accident in a nuclear power plant, iodine is a major contributor to the potential health risks for the public. Because the amount of iodine released largely depends on its volatility, iodine's behavior in containment has been extensively studied in international programs such as International Source Term Programme-Experimental Program on Iodine Chemistry under Radiation (EPICUR), Organization for Economic Co-operation and Development (OECD)-Behaviour of Iodine Project, and OECD-Source Term Evaluation and Mitigation. Korea Institute of Nuclear Safety (KINS) has joined these programs and is developing a simplified, stand-alone iodine chemistry model, RAIM (Radio-Active Iodine chemistry Model), based on the IMOD methodology and other previous studies. This model deals with chemical reactions associated with the formation and destruction of iodine species and surface reactions in the containment atmosphere and the sump in a simple manner. RAIM was applied to a simulation of four EPICUR tests and one Radioiodine Test Facility test, which were carried out in aqueous or gaseous phases. After analysis, the results show a trend of underestimation of organic and molecular iodine for the gas-phase experiments, the opposite of that for the aqueous-phase ones, whereas the total amount of volatile iodine species agrees well between the experiment and the analysis result.

  5. Engineering Model Propellant Feed System Development for an Iodine Hall Thruster Demonstration Mission

    Science.gov (United States)

    Polzin, Kurt A.

    2016-01-01

    CUBESATS are relatively new spacecraft platforms that are typically deployed from a launch vehicle as a secondary payload, providing low-cost access to space for a wide range of end-users. These satellites are comprised of building blocks having dimensions of 10x10x10 cu cm and a mass of 1.33 kg (a 1-U size). While providing low-cost access to space, a major operational limitation is the lack of a propulsion system that can fit within a CubeSat and is capable of executing high (Delta)v maneuvers. This makes it difficult to use CubeSats on missions requiring certain types of maneuvers (i.e. formation flying, spacecraft rendezvous). Recently, work has been performed investigating the use of iodine as a propellant for Hall-effect thrusters (HETs) 2 that could subsequently be used to provide a high specific impulse path to CubeSat propulsion. 3, 4 Iodine stores as a dense solid at very low pressures, making it acceptable as a propellant on a secondary payload. It has exceptionally high ?Isp (density times specific impulse), making it an enabling technology for small satellite near-term applications and providing the potential for systems-level advantages over mid-term high power electric propulsion options. Iodine flow can also be thermally regulated, subliming at relatively low temperature (< 100 C) to yield I2 vapor at or below 50 torr. At low power, the measured performance of an iodine-fed HET is very similar to that of a state-of-the-art xenon-fed thruster. Just as importantly, the current-voltage discharge characteristics of low power iodine-fed and xenon-fed thrusters are remarkably similar, potentially reducing development and qualifications costs by making it possible to use an already-qualified xenon-HET PPU in an iodine-fed system. Finally, a cold surface can be installed in a vacuum test chamber on which expended iodine propellant can deposit. In addition, the temperature doesn't have to be extremely cold to maintain a low vapor pressure in the vacuum

  6. Mixed additive models

    Science.gov (United States)

    Carvalho, Francisco; Covas, Ricardo

    2016-06-01

    We consider mixed models y =∑i =0 w Xiβi with V (y )=∑i =1 w θiMi Where Mi=XiXi⊤ , i = 1, . . ., w, and µ = X0β0. For these we will estimate the variance components θ1, . . ., θw, aswell estimable vectors through the decomposition of the initial model into sub-models y(h), h ∈ Γ, with V (y (h ))=γ (h )Ig (h )h ∈Γ . Moreover we will consider L extensions of these models, i.e., y˚=Ly+ɛ, where L=D (1n1, . . ., 1nw) and ɛ, independent of y, has null mean vector and variance covariance matrix θw+1Iw, where w =∑i =1 n wi .

  7. The Additive Hazard Mixing Models

    Institute of Scientific and Technical Information of China (English)

    Ping LI; Xiao-liang LING

    2012-01-01

    This paper is concerned with the aging and dependence properties in the additive hazard mixing models including some stochastic comparisons.Further,some useful bounds of reliability functions in additive hazard mixing models are obtained.

  8. Microwave-Accelerated Iodination of Some Aromatic Amines, Using Urea-Hydrogen Peroxide Addition Compound (UHP as the Oxidant

    Directory of Open Access Journals (Sweden)

    Lech Skulski

    2002-12-01

    Full Text Available A fast and simple method for the oxidative iodination of some aromatic amines, under microwave irradiation, is reported, using diiodine and the the strongly Hbonded urea-hydrogen peroxide addition compound (H2NCONH2···H2O2, UHP as the oxidant. The reactions were carried out in boiling CHCl3 under a reflux condenser to afford, within 10 minutes, the purified monoiodinated products in 40-80% yields.

  9. Impact of Aliquat {sup registered} 336 addition on organic iodine retention in containment-venting-scrubbing solutions for mitigation of severe accidents

    Energy Technology Data Exchange (ETDEWEB)

    Stahl, A.; Zeh, P.; Buhlmann, S. [AREVA NP GmbH, Erlangen (Germany)

    2013-07-01

    To mitigate severe accident situations Filtered Containment Venting Systems have been designed, internationally qualified and implemented in modern nuclear power plants (NPPs) in order to minimize radionuclide release to environment in case of containment pressure reduction via venting. Main focus was given to the reliable and efficient aerosol retention. In addition also efficient iodine retention was requested, as this element has significant activity content in nuclear fuel in combination with high volatility and radiotoxicity. Therefore, effort is made to reduce the iodine activity in venting gases. State-of-the-art containment venting scrubbing solutions use a solution of sodium hydroxide and sodium thiosulfate in order to wash out volatile iodine species. With such a solution high retention efficiencies for elemental iodine and hydrogen iodide are achieved. Nevertheless, the retention of organic iodine species in this solution is not satisfying and the search for improvements is ongoing. A possible additive presented in literature is Aliquat {sup registered} 336 promising improved retention of volatile organic iodine species in scrubbing solutions. This Aliquat {sup registered} 336 is a water insoluble quaternary ammonium chloride salt made by the methylation of mixed tri-octyl/decyl amine. The effectiveness of such an additive was tested at elevated temperatures and pressures simulating containment venting conditions. (orig.)

  10. Modelling molecular iodine emissions in a coastal marine environment: the link to new particle formation

    Science.gov (United States)

    Saiz-Lopez, A.; Plane, J. M. C.; McFiggans, G.; Williams, P. I.; Ball, S. M.; Bitter, M.; Jones, R. L.; Hongwei, C.; Hoffmann, T.

    2006-03-01

    A model of iodine chemistry in the marine boundary layer (MBL) has been used to investigate the impact of daytime coastal emissions of molecular iodine (I2). The model contains a full treatment of gas-phase iodine chemistry, combined with a description of the nucleation and growth, by condensation and coagulation, of iodine oxide nano-particles. In-situ measurements of coastal emissions of I2 made by the broadband cavity ring-down spectroscopy (BBCRDS) and inductively coupled plasma-mass spectrometry (ICP/MS) techniques are presented and compared to long path differential optical absorption spectroscopy (DOAS) observations of I2 at Mace Head, Ireland. Simultaneous measurements of enhanced I2 emissions and particle bursts show that I2 is almost certainly the main precursor of new particles at this coastal location. The ratio of IO to I2 predicted by the model indicates that the iodine species observed by the DOAS are concentrated over a short distance (about 8% of the 4.2 km light path) consistent with the intertidal zone, bringing them into good agreement with the I2 measurements made by the two in-situ techniques. The model is then used to investigate the effect of iodine emission on ozone depletion, and the production of new particles and their evolution to form stable cloud condensation nuclei (CCN).

  11. Modelling molecular iodine emissions in a coastal marine environment: the link to new particle formation

    Directory of Open Access Journals (Sweden)

    A. Saiz-Lopez

    2006-01-01

    Full Text Available A model of iodine chemistry in the marine boundary layer (MBL has been used to investigate the impact of daytime coastal emissions of molecular iodine (I2. The model contains a full treatment of gas-phase iodine chemistry, combined with a description of the nucleation and growth, by condensation and coagulation, of iodine oxide nano-particles. In-situ measurements of coastal emissions of I2 made by the broadband cavity ring-down spectroscopy (BBCRDS and inductively coupled plasma-mass spectrometry (ICP/MS techniques are presented and compared to long path differential optical absorption spectroscopy (DOAS observations of I2 at Mace Head, Ireland. Simultaneous measurements of enhanced I2 emissions and particle bursts show that I2 is almost certainly the main precursor of new particles at this coastal location. The ratio of IO to I2 predicted by the model indicates that the iodine species observed by the DOAS are concentrated over a short distance (about 8% of the 4.2 km light path consistent with the intertidal zone, bringing them into good agreement with the I2 measurements made by the two in-situ techniques. The model is then used to investigate the effect of iodine emission on ozone depletion, and the production of new particles and their evolution to form stable cloud condensation nuclei (CCN.

  12. Mixing effects in postdischarge modeling of electric discharge oxygen-iodine laser experiments

    Science.gov (United States)

    Palla, Andrew D.; Carroll, David L.; Verdeyen, Joseph T.; Solomon, Wayne C.

    2006-07-01

    In an electric discharge oxygen-iodine laser, laser action at 1315nm on the I(P1/22)→I(P3/22) transition of atomic iodine is obtained by a near resonant energy transfer from O2(aΔ1) which is produced using a low-pressure electric discharge. The discharge production of atomic oxygen, ozone, and other excited species adds higher levels of complexity to the postdischarge kinetics which are not encountered in a classic purely chemical O2(aΔ1) generation system. Mixing effects are also present. In this paper we present postdischarge modeling results obtained using a modified version of the BLAZE-II gas laser code. A 28 species, 105 reaction chemical kinetic reaction set for the postdischarge kinetics is presented. Calculations were performed to ascertain the impact of a two stream mixing mechanism on the numerical model and to study gain as a function of reactant mass flow rates. The calculations were compared with experimental data. Agreement with experimental data was improved with the addition of new kinetics and the mixing mechanism.

  13. Estimation of iodine nutrition and thyroid function status in late-gestation pregnant women in the United States: Development and application of a population-based pregnancy model.

    Science.gov (United States)

    Lumen, A; George, N I

    2017-01-01

    Previously, a deterministic biologically-based dose-response (BBDR) pregnancy model was developed to evaluate moderate thyroid axis disturbances with and without thyroid-active chemical exposure in a near-term pregnant woman and fetus. In the current study, the existing BBDR model was adapted to include a wider functional range of iodine nutrition, including more severe iodine deficiency conditions, and to incorporate empirically the effects of homeostatic mechanisms. The extended model was further developed into a population-based model and was constructed using a Monte Carlo-based probabilistic framework. In order to characterize total (T4) and free (fT4) thyroxine levels for a given iodine status at the population-level, the distribution of iodine intake for late-gestation pregnant women in the U.S was reconstructed using various reverse dosimetry methods and available biomonitoring data. The range of median (mean) iodine intake values resulting from three different methods of reverse dosimetry tested was 196.5-219.9μg of iodine/day (228.2-392.9μg of iodine/day). There was minimal variation in model-predicted maternal serum T4 and ft4 thyroxine levels from use of the three reconstructed distributions of iodine intake; the range of geometric mean for T4 and fT4, was 138-151.7nmol/L and 7.9-8.7pmol/L, respectively. The average value of the ratio of the 97.5th percentile to the 2.5th percentile equaled 3.1 and agreed well with similar estimates from recent observations in third-trimester pregnant women in the U.S. In addition, the reconstructed distributions of iodine intake allowed us to estimate nutrient inadequacy for late-gestation pregnant women in the U.S. via the probability approach. The prevalence of iodine inadequacy for third-trimester pregnant women in the U.S. was estimated to be between 21% and 44%. Taken together, the current work provides an improved tool for evaluating iodine nutritional status and the corresponding thyroid function status in

  14. Simulation of ISTP-EPICUR Iodine Chemistry Tests with RAIM

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Han-Chul; Cho, Yeong-Hun; Jang, Dong-Ju; Ryu, Myung-Hyun [Nuclear Korea Institute of Nuclear Safety, Daejeon (Korea, Republic of)

    2014-10-15

    The amount of iodine release largely depends on its volatility in the containment. Iodine has several chemical forms including aerosols, vapor, and gas. Among them gaseous iodine such as I{sub 2} and organic iodide are dominating due to their high volatility. Therefore, such iodine behavior has been extensively examined. Korea Institute of Nuclear Safety (KINS) has been joining the relevant international programs such as ISTP-EPICUR, OECD-BIP and OECD-STEM. In the course of this study, a simple iodine model, RAIM (Radio-Active Iodine chemistry Model) has been developed, based on the IMOD methodology and other previous studies. This model deals with chemical reactions associated with formation and destruction of iodine species in the containment atmosphere and the sump in a simple manner, as shown in Fig. 1. It also treats adsorption and desorption of volatile iodine on the paint surface. The iodine species modeled are inorganic volatile iodine, organic iodides of high volatility (HVRI) and low volatility (LVRI), non-volatiles, non-aqueous iodine, and iodine oxide aerosols (IO{sub x}). Many other material participating in the iodine reactions, e.g., air radiolysis products (ARP) such as ozone, are also modeled. This paper especially shows the analysis results after addition of gaseous reaction model to RAIM, which was further accompanied by adjustments of the existing reaction rate constants even for the aqueous reactions. After integration of iodine reaction models for gas and aqueous phase, RAIM was applied the S1-9 and S1-11 tests which were carried out in aqueous phase. In addition, re-analysis of the S2-6-5-2 test, for which iodine-loaded coupons were tested in gas phase, was also performed.

  15. Model of iodine transport and reaction kinetics in a nuclear fuel reprocessing plant

    Energy Technology Data Exchange (ETDEWEB)

    Davis, W. Jr.

    1977-05-01

    A model is presented to describe the time-dependent flow and retention of stable iodine isotopes and the decay of /sup 131/I in a nuclear fuel reprocessing plant. The plant consists of 16 units of equipment such as a voloxidizer or graphite burner, fuel dissolver, solvent extractors, storage tanks, vaporizers, primary iodine sorbers, and silver zeolite. The rate of accumulation of bulk and radioactive iodine in these units and in the environment is described using 19 differential equations. Reasonable time-dependence of iodine retention factors (RFs) by the plant were calculated. RFs for a new plant in excess of 10/sup 6/ for stable iodine and /sup 129/I decrease to the range of 10/sup 3/ to 10/sup 2/ as plant operating times exceed 50 to 100 days. The RFs for /sup 131/I also decrease initially, for a period of approximately 10 days, but then increase by several orders of magnitude due to radioactive decay and isotopic exchange. Generally, the RFs for /sup 131/I exceed those for stable iodine by factors of 10/sup 4/ or more. 19 references, 13 figures, 2 tables. (DLC)

  16. Iodine's impact on tropospheric oxidants: a global model study in GEOS-Chem

    Science.gov (United States)

    Sherwen, T.; Evans, M. J.; Carpenter, L. J.; Andrews, S. J.; Lidster, R. T.; Dix, B.; Koenig, T. K.; Sinreich, R.; Ortega, I.; Volkamer, R.; Saiz-Lopez, A.; Prados-Roman, C.; Mahajan, A. S.; Ordóñez, C.

    2016-02-01

    We present a global simulation of tropospheric iodine chemistry within the GEOS-Chem chemical transport model. This includes organic and inorganic iodine sources, standard gas-phase iodine chemistry, and simplified higher iodine oxide (I2OX, X = 2, 3, 4) chemistry, photolysis, deposition, and parametrized heterogeneous reactions. In comparisons with recent iodine oxide (IO) observations, the simulation shows an average bias of ˜ +90 % with available surface observations in the marine boundary layer (outside of polar regions), and of ˜ +73 % within the free troposphere (350 hPa terms of global tropospheric IY burden (contributing up to 70 %). The iodine chemistry leads to a significant global tropospheric O3 burden decrease (9.0 %) compared to standard GEOS-Chem (v9-2). The iodine-driven OX loss rate1 (748 Tg OX yr-1) is due to photolysis of HOI (78 %), photolysis of OIO (21 %), and reaction between IO and BrO (1 %). Increases in global mean OH concentrations (1.8 %) by increased conversion of hydroperoxy radicals exceeds the decrease in OH primary production from the reduced O3 concentration. We perform sensitivity studies on a range of parameters and conclude that the simulation is sensitive to choices in parametrization of heterogeneous uptake, ocean surface iodide, and I2OX (X = 2, 3, 4) photolysis. The new iodine chemistry combines with previously implemented bromine chemistry to yield a total bromine- and iodine-driven tropospheric O3 burden decrease of 14.4 % compared to a simulation without iodine and bromine chemistry in the model, and a small increase in OH (1.8 %). This is a significant impact and so halogen chemistry needs to be considered in both climate and air quality models. 1 Here OX is defined as O3 + NO2 + 2NO3 + PAN + PMN+PPN + HNO4 + 3N2O5 + HNO3 + BrO + HOBr + BrNO2+2BrNO3 + MPN + IO + HOI + INO2 + 2INO3 + 2OIO+2I2O2 + 3I2O3 + 4I2O4, where PAN = peroxyacetyl nitrate, PPN = peroxypropionyl nitrate, MPN = methyl peroxy nitrate, and MPN

  17. Modelling of iodine-induced stress corrosion cracking in CANDU fuel

    Science.gov (United States)

    Lewis, B. J.; Thompson, W. T.; Kleczek, M. R.; Shaheen, K.; Juhas, M.; Iglesias, F. C.

    2011-01-01

    Iodine-induced stress corrosion cracking (I-SCC) is a recognized factor for fuel-element failure in the operation of nuclear reactors requiring the implementation of mitigation measures. I-SCC is believed to depend on certain factors such as iodine concentration, oxide layer type and thickness on the fuel sheath, irradiation history, metallurgical parameters related to sheath like texture and microstructure, and the mechanical properties of zirconium alloys. This work details the development of a thermodynamics and mechanistic treatment accounting for the iodine chemistry and kinetics in the fuel-to-sheath gap and its influence on I-SCC phenomena. The governing transport equations for the model are solved with a finite-element technique using the COMSOL Multiphysics® commercial software platform. Based on this analysis, this study also proposes potential remedies for I-SCC.

  18. Business models for additive manufacturing

    DEFF Research Database (Denmark)

    Hadar, Ronen; Bilberg, Arne; Bogers, Marcel

    2015-01-01

    Digital fabrication — including additive manufacturing (AM), rapid prototyping and 3D printing — has the potential to revolutionize the way in which products are produced and delivered to the customer. Therefore, it challenges companies to reinvent their business model — describing the logic...... of creating and capturing value. In this paper, we explore the implications that AM technologies have for manufacturing systems in the new business models that they enable. In particular, we consider how a consumer goods manufacturer can organize the operations of a more open business model when moving from...... a manufacturer-centric to a consumer-centric value logic. A major shift includes a move from centralized to decentralized supply chains, where consumer goods manufacturers can implement a “hybrid” approach with a focus on localization and accessibility or develop a fully personalized model where the consumer...

  19. Modelling iodide – iodate speciation in atmospheric aerosol: Contributions of inorganic and organic iodine chemistry

    Directory of Open Access Journals (Sweden)

    S. Pechtl

    2007-01-01

    Full Text Available The speciation of iodine in atmospheric aerosol is currently poorly understood. Models predict negligible iodide concentrations but accumulation of iodate in aerosol, both of which is not confirmed by recent measurements. We present an updated aqueous phase iodine chemistry scheme for use in atmospheric chemistry models and discuss sensitivity studies with the marine boundary layer model MISTRA. These studies show that iodate can be reduced in acidic aerosol by inorganic reactions, i.e., iodate does not necessarily accumulate in particles. Furthermore, the transformation of particulate iodide to volatile iodine species likely has been overestimated in previous model studies due to negligence of collision-induced upper limits for the reaction rates. However, inorganic reaction cycles still do not seem to be sufficient to reproduce the observed range of iodide – iodate speciation in atmospheric aerosol. Therefore, we also investigate the effects of the recently suggested reaction of HOI with dissolved organic matter to produce iodide. If this reaction is fast enough to compete with the inorganic mechanism, it would not only directly lead to enhanced iodide concentrations but, indirectly via speed-up of the inorganic iodate reduction cycles, also to a decrease in iodate concentrations. Hence, according to our model studies, organic iodine chemistry, combined with inorganic reaction cycles, is able to reproduce observations. The presented chemistry cycles are highly dependent on pH and thus offer an explanation for the large observed variability of the iodide – iodate speciation in atmospheric aerosol.

  20. Assessment of spatial variation in drinking water iodine and its implications for dietary intake: A new conceptual model for Denmark

    Energy Technology Data Exchange (ETDEWEB)

    Voutchkova, Denitza Dimitrova, E-mail: ddv@geo.au.dk [Department of Geoscience, Aarhus University, Høegh-Guldbergs Gade 2, DK-8000 Aarhus C (Denmark); Geological Survey of Denmark and Greenland (GEUS), Lyseng Allé 1, DK-8270 Højbjerg (Denmark); Geological Survey of Denmark and Greenland (GEUS), Øster Voldgade 10, DK-1350 Copenhagen K (Denmark); Ernstsen, Vibeke [Geological Survey of Denmark and Greenland (GEUS), Øster Voldgade 10, DK-1350 Copenhagen K (Denmark); Hansen, Birgitte; Sørensen, Brian Lyngby [Geological Survey of Denmark and Greenland (GEUS), Lyseng Allé 1, DK-8270 Højbjerg (Denmark); Zhang, Chaosheng [GIS Centre and School of Geography and Archaeology, National University of Ireland, Galway (Ireland); Kristiansen, Søren Munch [Department of Geoscience, Aarhus University, Høegh-Guldbergs Gade 2, DK-8000 Aarhus C (Denmark)

    2014-09-15

    Iodine is essential for human health. Many countries have therefore introduced universal salt iodising (USI) programmes to ensure adequate intake for the populations. However, little attention has been paid to subnational differences in iodine intake from drinking water caused by naturally occurring spatial variations. To address this issue, we here present the results of a Danish nationwide study of spatial trends of iodine in drinking water and the relevance of these trends for human dietary iodine intake. The data consist of treated drinking water samples from 144 waterworks, representing approx. 45% of the groundwater abstraction for drinking water supply in Denmark. The samples were analysed for iodide, iodate, total iodine (TI) and other major and trace elements. The spatial patterns were investigated with Local Moran's I. TI ranges from < 0.2 to 126 μg L{sup −1} (mean 14.4 μg L{sup −1}, median 11.9 μg L{sup −1}). Six speciation combinations were found. Half of the samples (n = 71) contain organic iodine; all species were detected in approx. 27% of all samples. The complex spatial variation is attributed both to the geology and the groundwater treatment. TI > 40 μg L{sup −1} originates from postglacial marine and glacial meltwater sand and from Campanian–Maastrichtian chalk aquifers. The estimated drinking water contribution to human intake varies from 0% to > 100% of the WHO recommended daily iodine intake for adults and from 0% to approx. 50% for adolescents. The paper presents a new conceptual model based on the observed clustering of high or low drinking-water iodine concentrations, delimiting zones with potentially deficient, excessive or optimal iodine status. Our findings suggest that the present coarse-scale nationwide programme for monitoring the population's iodine status may not offer a sufficiently accurate picture. Local variations in drinking-water iodine should be mapped and incorporated into future adjustment of the

  1. [Iodine deficiency in pregnancy--a continuing public health problem].

    Science.gov (United States)

    Szybiński, Zbigniew

    2005-01-01

    Iodine prophylaxis in Poland started in 1997 and is based on mandatory iodzation of household salt with 20-40 mg KI/ 1 kg, supplementation of bottle fed infants with iodized formulas with 10,0 microg KI/100 ml, and a voluntary supplementation of pregnant and breast feeding women with additional 100-150 microg of iodine/ day. Last evaluation of efficacy of the iodine prophylaxis performed in 2003 by WHO and International Council for the Control of Iodine Deficiency Disorders allocated Poland within the group of the European countries with sufficient iodine supplementation on the population level. However according to data of the Institute of Mather and Chield in Poland, around 50 % of pregnant women only is additionally supplemented with iodine. Iodine deficiency during pregnancy even as a moderate iodine deficiency, creates a risk of mental retardation, perinatal complication like low and very low births weigt of neonates with increased perinatal mortality rate and late consequences in adult life: metabolic syndrom and type 2 diabetes. Another limitation of the actual model of iodine prophylaxis in Poland, it is too high consumption of natrum chloride (over 5,0 g of household salt/day/ capita). It is around 50% over WHO recommendation. Intensive preventive program against hypertension, type 2 diabetes, atherosclerosis, osteoporosis and some neoplasmatic diseases includes limitation of natrum chloride consumption- as one of the risk factors. Therefore new scope of the National Programme for Elimination of Iodine Deficiency will include: a special prorgramme for the iodization of animal food according to european standard, increased rate of pregnant women additionally supplemented with iodine, strengthening public awarness on necessary increase of milk consumption especially in pregnancy and in children and continouse monitoring system of biologic effects and technologic quality of the model of iodine prophylaxis.

  2. Overview of the ACEX project iodine work

    Energy Technology Data Exchange (ETDEWEB)

    Merilo, M.

    1996-12-01

    The ACEX project is an internationally sponsored research program that focuses on several aspects of severe accidents. The areas addressed are iodine behavior in containments, pool scrubbing, molten corium concrete interactions, and ex-vessel core debris coolability. These areas all represent extensions to the previous and current ACE and MACE programs respectively. The ACE-Phase B (iodine) project, and other recent research efforts, have clarified the roles of the important phenomena that influence iodine volatility in reactor containments during severe accidents. The ACE Iodine Chemistry Subcommittee concluded that even though enough data has been generated to support reasonably good quantification of the important phenomena, a few important areas remain where quantification is still uncertain. This is due to a lack of agreement on how to utilize the existing database, as well as the possible absence of critical test and/or property data. Technical resolution of the overall iodine behavior issue is therefore not feasible until these uncertainties are fully assessed and practical solutions have been identified, implemented, and verified. The overall objectives of the ACEX iodine research program are to ensure that the iodine database can be used to predict the airborne concentration of iodine, the conditions for iodine reservoir stability, and to provide a mechanistic understanding for these phenomena. The first phase of this work involves a comprehensive review and interpretation of the existing database in order to formulate practical strategies for dealing with significant uncertainties and/or deficiencies. Several projects are underway involving the effects of organic reactions and structural surface interactions. In addition effort is being expended on standardizing the aqueous iodine kinetics database, specifying useful mass transfer models, and defining methodology for pH prediction. (Abstract Truncated)

  3. Scientific Opinion on the safety and efficacy of iodine compounds (E2 as feed additives for all species: calcium iodate anhydrous and potassium iodide, based on a dossier submitted by HELM AG

    Directory of Open Access Journals (Sweden)

    EFSA Panel on Additives and Products or Substances used in Animal Feed (FEEDAP

    2013-02-01

    Full Text Available Calcium iodate anhydrous and potassium iodide are considered safe sources of iodine for all animal species/categories when used up to the currently authorised maximum content of total iodine in complete feed, with the exception of horses and dogs, for which maximum tolerated levels are 3 and 4 mg I/kg complete feed, respectively. The limited data available on iodine tolerance in cats support a provisional tolerated level of 5 mg I/kg complete feed. Exposure of consumers was calculated in two scenarios applying the currently authorised maximum iodine contents in feed and reduced contents. The iodine content of food of animal origin, if produced taking account of the currently authorised maximum content of iodine in feed, would represent a substantial risk to high consumers. The risk would originate primarily from the consumption of milk and to a minor extent from eggs. The UL for adults (600 µg/day and for toddlers (200 µg/day would be exceeded by a factor of 2 and  4, respectively. If the authorised maximum iodine in feed for dairy cows and laying hens were reduced to 2 and 3 mg I/kg feed, respectively, the exposure of adult consumers would be below the UL. However, iodine intake in high-consuming toddlers would remain above the UL (1.6-fold. The additives are considered as irritant to the eyes, skin and respiratory tract, and as dermal sensitisers. Exposure by inhalation should be avoided. The use of the additives in animal nutrition is not expected to pose a risk to the environment. The additives are efficacious to meet animal iodine requirements. The FEEDAP Panel recommends that the maximum iodine contents in complete feed be reduced as follows: dairy cows and minor dairy ruminants, 2 mg I/kg; laying hens, 3 mg I/kg; horses, 3 mg I/kg; dogs, 4 mg I/kg; cats, 5 mg I/kg.

  4. Theoretical modeling of iodine value and saponification value of biodiesel fuels from their fatty acid composition

    Energy Technology Data Exchange (ETDEWEB)

    Gopinath, A.; Puhan, Sukumar; Nagarajan, G. [Internal Combustion Engineering Division, Department of Mechanical Engineering, Anna University, Chennai 600 025, Tamil Nadu (India)

    2009-07-15

    Biodiesel is an alternative fuel consisting of alkyl esters of fatty acids from vegetable oils or animal fats. The properties of biodiesel depend on the type of vegetable oil used for the transesterification process. The objective of the present work is to theoretically predict the iodine value and the saponification value of different biodiesels from their fatty acid methyl ester composition. The fatty acid ester compositions and the above values of different biodiesels were taken from the available published data. A multiple linear regression model was developed to predict the iodine value and saponification value of different biodiesels. The predicted results showed that the prediction errors were less than 3.4% compared to the available published data. The predicted values were also verified by substituting in the available published model which was developed to predict the higher heating values of biodiesel fuels from their iodine value and the saponification value. The resulting heating values of biodiesels were then compared with the published heating values and reported. (author)

  5. Assessment of iodine nutrition in populations: past, present, and future.

    Science.gov (United States)

    Zimmermann, Michael B; Andersson, Maria

    2012-10-01

    Iodine status has been historically assessed by palpation of the thyroid and reported as goiter rates. Goiter is a functional biomarker that can be applied to both individuals and populations, but it is subjective. Iodine status is now assessed using an objective biomarker of exposure, i.e., urinary iodine concentrations (UICs) in spot samples and comparison of the median UIC to UIC cut-offs to categorize population status. This has improved standardization, but inappropriate use of the crude proportion of UICs below the cut-off level of 100 µg/L to estimate the number of iodine-deficient children has led to an overestimation of the prevalence of iodine deficiency. In this review, a new approach is proposed in which UIC data are extrapolated to iodine intakes, adjusted for intraindividual variation, and then interpreted using the estimated average requirement cut-point model. This may allow national programs to define the prevalence of iodine deficiency in the population and to quantify the necessary increase in iodine intakes to ensure sufficiency. In addition, thyroglobulin can be measured on dried blood spots to provide an additional sensitive functional biomarker of iodine status.

  6. Iodine Deficiency

    Science.gov (United States)

    ... 2017 By ATA | Featured , Iodine Deficiency , News Releases , Potassium Iodide (KI) | No Comments IDD NEWSLETTER – February 2017 VOLUME ... 2016 By ATA | Featured , Iodine Deficiency , News Releases , Potassium Iodide (KI) | No Comments IDD NEWSLETTER – November 2015 (PDF ...

  7. Iodine Deficiency

    Science.gov (United States)

    ... 0 Iodine Daily Serving now recommended in Multivitamin/Mineral Supplements for Pregnant and Lactating Women By ATA | 2015 News Releases , Iodine Deficiency , News Releases , Thyroid Disease and Pregnancy | No Comments Falls Church, February 10, 2015 —The ...

  8. Comprehensive study of efficient dye-sensitized solar cells based on the binary ionic liquid electrolyte by modifying with additives and iodine

    Science.gov (United States)

    Mo, Ao-qiang; Cao, Da-peng; Wang, Wu-yang; Li, Xue-yan; Mi, Bao-xiu; Gao, Zhi-qiang; Liang, Zhong-cheng

    2017-07-01

    The photovoltaic performance of dye-sensitized solar cells (DSSCs) is enhanced by modifying the binary room temperature ionic liquid (RTIL) electrolyte with additives and iodine. The average photoelectric conversion efficiency ( PCE) of 6.39% is achieved. Through electrochemical impedance spectroscopy (EIS), cyclic voltammetry scans and incident photon-to-current conversion efficiency ( IPCE) data, the working principles are analyzed. The enhancement is mainly attributed to the improvement of short circuit current which is caused by the reduction of overall internal resistance of the devices. Durability tests are measured at room temperature, and the long-term stability performance can be maintained.

  9. Iodine Deficiency

    NARCIS (Netherlands)

    Zimmermann, M.B.

    2009-01-01

    Iodine deficiency has multiple adverse effects in humans, termed iodine deficiency disorders, due to inadequate thyroid hormone production. Globally, it is estimated that 2 billion individuals have an insufficient iodine intake, and South Asia and sub-Saharan Africa are particularly affected. Howeve

  10. Iodine Deficiency

    NARCIS (Netherlands)

    Zimmermann, M.B.

    2009-01-01

    Iodine deficiency has multiple adverse effects in humans, termed iodine deficiency disorders, due to inadequate thyroid hormone production. Globally, it is estimated that 2 billion individuals have an insufficient iodine intake, and South Asia and sub-Saharan Africa are particularly affected. Howeve

  11. [Improving the human iodine supply by iodination of swine feed].

    Science.gov (United States)

    Rambeck, W A; Kaufmann, S; Feng, J; Hollwich, W; Arnold, R

    1997-07-01

    Germany and several other countries are areas of severe iodine deficiency. In addition to iodized salt additional strategies to fight iodine deficiency exist. A promising possibility is the supplementation of feed with iodine, in order to increase its content in food of animal origin. In a feeding experiment 24 male castrated and female piglets of the cross breed Deutsche Landrasse x Pietrain were fed a high iodine supplemented diet. At a body weight of 100 kg the animals were slaughtered and the effect of the iodine supplementation on iodine content in the organs was studied. Animals receiving 30 mg iodine/kg feed showed significantly higher iodine contents in muscle, heart, kidney, liver, serum, fat and in the thyroidea than animals receiving no iodine supplementation. The iodine content in muscle and organs increased by a factor three to seven. Concerning meat quality and other slaughter parameters there was no difference between the two groups. This demonstrates that this strategy is in addition to iodized salt a possibility to reduce iodine deficiency.

  12. Organic iodine chemistry

    Energy Technology Data Exchange (ETDEWEB)

    Dickinson, S. E-mail: shirley.dickinson@aeat.co.uk; Sims, H.E.; Belval-Haltier, E.; Jacquemain, D.; Poletiko, C.; Funke, F.; Hellmann, S.; Karjunen, T.; Zilliacus, R

    2001-11-01

    A shared-cost action on Organic Iodine Chemistry has been completed as part of the CEC 4th Framework programme on Nuclear Fission Safety. Organisations from four EC countries are involved in an integrated programme of experiments and analysis to help clarify the phenomenology, and to increase confidence in the modelling of iodine behaviour in containment. The project is focused on identifying the main routes for organic iodine formation, and providing new experimental kinetic data which will be used to improve existing models and to stimulate code development.

  13. Development of an equivalent-circuit model for the lithium/iodine battery

    Energy Technology Data Exchange (ETDEWEB)

    Schmidt, C.L. [Medtronic, Inc., Minneapolis, MN (United States); Skarstad, P.M. [Medtronic, Inc., Minneapolis, MN (United States)

    1997-03-01

    The lithium/iodine battery is the most widely used power source for implantable cardiac pacemakers. While the average power demands of pacemakers are very low, the instantaneous power requirements can challenge the capabilities of this high impedance battery. Thus, there is a need to predict the transient-response behavior of new battery designs. Impedance spectroscopy was used to characterize the behavior of a variety of cell designs as a function of cell design, depth-of-discharge, and current density. An equivalent-circuit model was developed in terms of the physical elements which contribute to electrical resistance, capacitance, and electrochemical polarization. The transient-response predicted by this simple equivalent-circuit model was compared to pulse data from actual batteries and found to be in excellent agreement. (orig.)

  14. Dutch distribution zones of stable iodine tablets based on atmospheric dispersion modelling of accidental releases from nuclear power plants.

    NARCIS (Netherlands)

    Kok-Palma, Y.S.; Leenders, M.; Meulenbelt, J.

    2010-01-01

    Rapid administration of stable iodine is essential for the saturation and subsequent protection of the thyroid gland against the potential harm caused by radioiodines. This paper proposes the Dutch risk analysis that uses an atmospheric dispersion model to calculate the size of the zones around nucl

  15. Further assessment of the chemical modelling of iodine in IMPAIR 3 code using ACE/RTF data

    Energy Technology Data Exchange (ETDEWEB)

    Cripps, R.C.; Guentay, S. [Paul Scherrer Inst. (PSI), Villigen (Switzerland)

    1996-12-01

    This paper introduces the assessment of the computer code IMPAIR 3 (Iodine Matter Partitioning And Iodine Release) which simulates physical and chemical iodine processes in a LWR containment with one or more compartments under conditions relevant to a severe accident in a nuclear reactor. The first version was published in 1992 to replace both the multi-compartment code IMPAIR 2/M and the single-compartment code IMPAIR 2.2. IMPAIR 2.2 was restricted to a single pH value specified before programme execution and precluded any variation of pH or calculation of H{sup +} changes during program execution. This restriction is removed in IMPAIR 3. Results of the IMPAIR 2.2 assessment using ACE/RTF Test 2 and the acidic phase of Test 3 B data were presented at the 3rd CSNI Workshop. The purpose of the current assessment is to verify the IMPAIR 3 capability to follow the whole test duration with changing boundary conditions. Besides revisiting ACE/RTF Test 3B, Test 4 data were also used for the current assessment. A limited data analysis was conducted using the outcome of the current ACEX iodine work to understand the iodine behaviour observed during these tests. This paper presents comparisons of the predicted results with the test data. The code capabilities are demonstrated to focus on still unresolved modelling problems. The unclear behaviour observed in the gaseous molecular iodine behaviour and its inconclusive effect on the calculated behaviour in the acidic phase of the Test 4 and importance of the catalytic effect of stainless steel are also indicated. (author) 18 figs., 1 tab., 11 refs.

  16. Iodine poisoning

    Science.gov (United States)

    Symptoms of iodine poisoning include: Abdominal pain Coughing Delirium Diarrhea , sometimes bloody Fever Gum and tooth soreness Loss of appetite Metallic taste in mouth Mouth and throat pain and burning No urine output Rash Salivation (producing saliva) Seizures ...

  17. Iodine Alters Gene Expression in the MCF7 Breast Cancer Cell Line: Evidence for an Anti-Estrogen Effect of Iodine

    Directory of Open Access Journals (Sweden)

    Frederick R. Stoddard II, Ari D. Brooks, Bernard A. Eskin, Gregg J. Johannes

    2008-01-01

    Full Text Available The protective effects of iodine on breast cancer have been postulated from epidemiologic evidence and described in animal models. The molecular mechanisms responsible have not been identified but laboratory evidence suggests that iodine may inhibit cancer promotion through modulation of the estrogen pathway. To elucidate the role of iodine in breast cancer, the effect of Lugol's iodine solution (5% I2, 10% KI on gene expression was analyzed in the estrogen responsive MCF-7 breast cancer cell line. Microarray analysis identified 29 genes that were up-regulated and 14 genes that were down-regulated in response to iodine/iodide treatment. The altered genes included several involved in hormone metabolism as well as genes involved in the regulation of cell cycle progression, growth and differentiation. Quantitative RT-PCR confirmed the array data demonstrating that iodine/iodide treatment increased the mRNA levels of several genes involved in estrogen metabolism (CYP1A1, CYP1B1, and AKR1C1 while decreasing the levels of the estrogen responsive genes TFF1 and WISP2. This report presents the results of the first gene array profiling of the response of a breast cancer cell line to iodine treatment. In addition to elucidating our understanding of the effects of iodine/iodide on breast cancer, this work suggests that iodine/iodide may be useful as an adjuvant therapy in the pharmacologic manipulation of the estrogen pathway in women with breast cancer.

  18. Effects of the Spectral Line Broadened Model on the Performance of a Flowing Chemical Oxygen-Iodine Laser

    Institute of Scientific and Technical Information of China (English)

    高智; 胡利民

    2002-01-01

    A new gain saturation model of chemical oxygen-iodine lasers (COILs) is deduced from the conservation equations of the population number of upper and lower lasing levels. The present model is compared with both the Voigt profile function model and its low-pressure limit model. The differences between the Voigt profile function model or its low-pressure limit model and the model presented here are pointed out, such as the length of power extraction, the optimal range of the threshold gain. These differences are useful for the optimization of COIL adjustable parameters.

  19. Modeling the possible role of iodine oxides in atmospheric new particle formation

    Directory of Open Access Journals (Sweden)

    S. Pechtl

    2006-01-01

    Full Text Available We studied the possible role of iodine oxides in atmospheric new particle formation with the one-dimensional marine boundary layer model MISTRA, which includes chemistry in the gas and aerosol phase as well as aerosol microphysics. The chemical reaction set focuses on halogen (Cl-Br-I chemistry. We included a two-step nucleation parameterization, where in the first step, the 'real' nucleation process is parameterized, i.e., the formation of cluster-sized nuclei via homogeneous condensation of gases. We considered both ternary sulfuric acid-ammonia-water nucleation and homomolecular homogeneous OIO nucleation. For the latter, we derived a parameterization based on combined laboratory-model studies. The second step of the nucleation parameterization treats the 'apparent' nucleation rate, i.e., the growth of clusters into the model's lowest size bin by condensable vapors such as OIO. We compared different scenarios for a clean marine versus a polluted continental background atmosphere. In every scenario, we assumed the air to move, independent of its origin, first over a coastal region (where it is exposed to surface fluxes of different reactive iodine precursors and later over the open ocean. According to these sensitivity studies, in the clean marine background atmosphere OIO can be responsible for both homogeneous nuclei formation and the subsequent growth of the clusters to detectable sizes. In contrast to this, in the continental case with its higher levels of pollutants, gas phase OIO mixing ratios, and hence related nucleation rates, are significantly lower. Compared to ternary H2SO4-NH3-H2O nucleation, homogeneous OIO nucleation can be neglected for new particle formation in this case, but OIO can contribute to early particle growth, i.e., to apparent nucleation rates. In general, we found OIO to be more important for the growth of newly formed particles than for the formation of new nuclei. According to our studies, observations of

  20. Development of Efficient Flowsheet and Transient Modeling for Nuclear Heat Coupled Sulfur Iodine Cyclefor Hydrogen Production

    Energy Technology Data Exchange (ETDEWEB)

    Shripad T. Revankar; Nicholas R. Brown; Cheikhou Kane; Seungmin Oh

    2010-05-01

    The realization of the hydrogen as an energy carrier for future power sources relies on a practical method of producing hydrogen in large scale with no emission of green house gases. Hydrogen is an energy carrier which can be produced by a thermochemical water splitting process. The Sulfur-Iodine (SI) process is an example of a water splitting method using iodine and sulfur as recycling agents.

  1. Iodinated (Perfluoro)alkyl Quinoxalines by Atom Transfer Radical Addition Using ortho-Diisocyanoarenes as Radical Acceptors.

    Science.gov (United States)

    Leifert, Dirk; Studer, Armido

    2016-09-12

    A simple method for the preparation of functionalized quinoxalines is reported. Starting from readily accessible ortho-diisocyanoarenes and (perfluoro)alkyl iodides, the quinoxaline core is constructed during (perfluoro)alkylation by atom transfer radical addition (ATRA), resulting in 2-iodo-3-(perfluoro)alkylquinoxalines. The radical cascades are readily initiated either with visible light or by using α,α'-azobisisobutyronitrile (AIBN). The heteroarene products are obtained in high yields (up to 94 %), and the method can be readily scaled up. Useful follow-up chemistry documents the value of the novel radical quinoxaline synthesis.

  2. Iodine oxide in the global marine boundary layer

    Directory of Open Access Journals (Sweden)

    C. Prados-Roman

    2014-08-01

    Full Text Available Emitted mainly by the oceans, iodine is a halogen compound important for atmospheric chemistry due to its high ozone depletion potential and effect on the oxidizing capacity of the atmosphere. Here we present a comprehensive dataset of iodine oxide (IO measurements in the open marine boundary layer (MBL made during the Malaspina 2010 circumnavigation. Results show IO mixing ratios ranging from 0.4 to 1 pmol mol−1 and, complemented with additional field campaigns, this dataset confirms through observations the ubiquitous presence of reactive iodine chemistry in the global marine environment. We use a global model with organic (CH3I, CH2ICl, CH2I2 and CH2IBr and inorganic (HOI and I2 iodine ocean emissions to investigate the contribution of the different iodine source gases to the budget of IO in the global MBL. In agreement with previous estimates, our results indicate that, globally averaged, the abiotic precursors contribute about 75% to the iodine oxide budget. However, this work reveals a strong geographical pattern in the contribution of organic vs. inorganic precursors to reactive iodine in the global MBL.

  3. Iodine biofortification of crops: agronomic biofortification, metabolic engineering and iodine bioavailability.

    Science.gov (United States)

    Gonzali, Silvia; Kiferle, Claudia; Perata, Pierdomenico

    2016-10-27

    Iodine deficiency is a widespread micronutrient malnutrition problem, and the addition of iodine to table salt represents the most common prophylaxis tool. The biofortification of crops with iodine is a recent strategy to further enrich the human diet with a potentially cost-effective, well accepted and bioavailable iodine source. Understanding how iodine functions in higher plants is key to establishing suitable biofortification approaches. This review describes the current knowledge regarding iodine physiology in higher plants, and provides updates on recent agronomic and metabolic engineering strategies of biofortification. Whereas the direct administration of iodine is effective to increase the iodine content in many plant species, a more sophisticated genetic engineering approach seems to be necessary for the iodine biofortification of some important staple crops.

  4. Identifying confounders using additive noise models

    CERN Document Server

    Janzing, Dominik; Mooij, Joris; Schoelkopf, Bernhard

    2012-01-01

    We propose a method for inferring the existence of a latent common cause ('confounder') of two observed random variables. The method assumes that the two effects of the confounder are (possibly nonlinear) functions of the confounder plus independent, additive noise. We discuss under which conditions the model is identifiable (up to an arbitrary reparameterization of the confounder) from the joint distribution of the effects. We state and prove a theoretical result that provides evidence for the conjecture that the model is generically identifiable under suitable technical conditions. In addition, we propose a practical method to estimate the confounder from a finite i.i.d. sample of the effects and illustrate that the method works well on both simulated and real-world data.

  5. Effects of iodinated contrast media in a novel model for cerebral vasospasm

    Directory of Open Access Journals (Sweden)

    Tatiana Nikitina

    2015-02-01

    Full Text Available Objective We developed an in vitro model for vasospasm post subarachnoid hemorrhage that was suitable for investigating brain vessel autoregulation. We further investigated the effects of iodinated contrast medium on the vascular tone and the myogenic response of spastic cerebral vessels. Method We isolated and perfused the superior cerebellar arteries of rats. The vessels were pressurized and studied under isobaric conditions. Coagulated blood was used to simulate subarachnoid hemorrhage. The contrast medium iodixanol was applied intraluminally. Results Vessels exposed to blood developed significantly stronger myogenic tone (65.7 ± 2.0% vs 77.1 ± 1.2% of the maximum diameter, for the blood and the control group, respectively and significantly decreased myogenic response, compared with the control groups. The contrast medium did not worsen the myogenic tone or the myogenic response in any group. Conclusion Our results show that deranged myogenic response may contribute to cerebral blood flow disturbances subsequent to subarachnoid hemorrhage. The contrast medium did not have any negative influence on vessel tone or myogenic response in this experimental setting.

  6. Kinetic modeling and energy efficiency of UV/H₂O₂ treatment of iodinated trihalomethanes.

    Science.gov (United States)

    Xiao, Yongjun; Zhang, Lifeng; Yue, Junqi; Webster, Richard D; Lim, Teik-Thye

    2015-05-15

    Photodegradation of I-THMs including CHCl2I and CHI3 by the UV/H2O2 system was investigated in this study. CHCl2I and CHI3 react rapidly with hydroxyl radical (OH) produced by the UV/H2O2 system, with second-order rate constants of 8.0 × 10(9) and 8.9 × 10(9) M(-1) s(-1), respectively. A fraction of CHCl2I could be completely mineralized within 15 min and the remaining fraction was mainly converted to formic acid (HCO2H). Cl(-) and I(-) were identified as the predominant end-products. No ClO3(-) was observed during the photodegradation process, while IO3(-) was detected but at less than 2% of the total liberated iodine species at the end of the reaction. The effects of pH, H2O2 dose, and matrix species such as humic acid (HA), HCO3(-), SO4(2-), Cl(-), NO3(-) on the photodegradation kinetics were evaluated. The steady-state kinetic model has been proven to successfully predict the destruction of CHCl2I and CHI3 by UV/H2O2 in different water matrices. On this basis, the kinetic model combined with electrical energy per order (EE/O) concept was applied to evaluate the efficiency of the photodegradation process and to optimize the H2O2 dose for different scenarios. The optimal H2O2 doses in deionized (DI) water, model natural water, and surface water are estimated at 5, 12, and 16 mg L(-1), respectively, which correspond to the lowest total energy consumption (EE/Ototal) of 0.2, 0.31, and 0.45 kWhm(-3)order(-1). Copyright © 2015 Elsevier Ltd. All rights reserved.

  7. A generalized additive regression model for survival times

    DEFF Research Database (Denmark)

    Scheike, Thomas H.

    2001-01-01

    Additive Aalen model; counting process; disability model; illness-death model; generalized additive models; multiple time-scales; non-parametric estimation; survival data; varying-coefficient models......Additive Aalen model; counting process; disability model; illness-death model; generalized additive models; multiple time-scales; non-parametric estimation; survival data; varying-coefficient models...

  8. A generalized additive regression model for survival times

    DEFF Research Database (Denmark)

    Scheike, Thomas H.

    2001-01-01

    Additive Aalen model; counting process; disability model; illness-death model; generalized additive models; multiple time-scales; non-parametric estimation; survival data; varying-coefficient models......Additive Aalen model; counting process; disability model; illness-death model; generalized additive models; multiple time-scales; non-parametric estimation; survival data; varying-coefficient models...

  9. Characterizing soil preferential flow using iodine--starch staining experiments and the active region model

    Energy Technology Data Exchange (ETDEWEB)

    Sheng, Feng; Wang, Kang; Zhang, Renduo; Liu, Hui-Hai

    2009-03-01

    Thirteen iodine-starch staining experiments with different boundary conditions and measurement scales were conducted at two sites to study preferential flow processes in natural unsaturated soils. Digital imaging analyses were implemented to obtain the corresponding preferential flow patterns. The test results are used to evaluate a recently proposed active region model in terms of its usefulness and robustness for characterizing unsaturated flow processes at field scale. Test results provide useful insights into flow patterns in unsaturated soils. They show that flow pattern depends on the top boundary condition. As the total infiltrating-water depth increased form 20 mm to 80 mm for the 100 x 100 cm{sup 2} plots, the corresponding flow pattern changed from few preferential flow paths associated with a relatively small degree of stained coverage and a small infiltration depth, to a pattern characterized by a higher stained coverage and a larger infiltration depth, and to (finally) a relatively homogeneous flow pattern with few unstained area and a much larger infiltration depth. Test results also show that the preferential flow pattern became generally more heterogeneous and complex for a larger measurement scale (or size of infiltration plot). These observations support the general idea behind the active region model that preferential flow pattern in unsaturated soils are dynamic and depend on water flow conditions. Further analyses of the test results indicate that the active-region model is able to capture the major features of the observed flow pattern at the scale of interest, and the determined parameter values do not significantly depend on the test conditions (initial water content and total amount of infiltrating water) for a given test site. This supports the validity of the active region model that considers that parameter to be a property of the corresponding unsaturated soil. Results also show that some intrinsic relation seems to exist between active-fracture-model

  10. Computational Process Modeling for Additive Manufacturing (OSU)

    Science.gov (United States)

    Bagg, Stacey; Zhang, Wei

    2015-01-01

    Powder-Bed Additive Manufacturing (AM) through Direct Metal Laser Sintering (DMLS) or Selective Laser Melting (SLM) is being used by NASA and the Aerospace industry to "print" parts that traditionally are very complex, high cost, or long schedule lead items. The process spreads a thin layer of metal powder over a build platform, then melts the powder in a series of welds in a desired shape. The next layer of powder is applied, and the process is repeated until layer-by-layer, a very complex part can be built. This reduces cost and schedule by eliminating very complex tooling and processes traditionally used in aerospace component manufacturing. To use the process to print end-use items, NASA seeks to understand SLM material well enough to develop a method of qualifying parts for space flight operation. Traditionally, a new material process takes many years and high investment to generate statistical databases and experiential knowledge, but computational modeling can truncate the schedule and cost -many experiments can be run quickly in a model, which would take years and a high material cost to run empirically. This project seeks to optimize material build parameters with reduced time and cost through modeling.

  11. Dual-phase dual-energy CT in patients with lung cancer: assessment of the additional value of iodine quantification in lymph node therapy response

    Energy Technology Data Exchange (ETDEWEB)

    Baxa, Jan; Vondrakova, Alena; Matouskova, Tana; Ferda, Jiri [Charles University Teaching Hospital Plzen, Department of Imaging Methods, Plzen (Czech Republic); Ruzickova, Olga [Charles University Teaching Hospital Plzen, Department of Pulmonary Diseases, Plzen (Czech Republic); Schmidt, Bernhard; Flohr, Thomas; Sedlmair, Martin [Siemens Healthcare, CT Physics and Applications Development, Forchheim (Germany)

    2014-08-15

    To investigate the potential contribution of iodine uptake calculation from dual-phase dual-energy CT (DE-CT) for lymph node staging and therapy response monitoring in lung cancer patients. Retrospective analysis of 27 patients with non-small cell lung carcinoma (NSCLC), who underwent dual-phase DE-CT before and after chemotherapy, was performed. Iodine uptake (mg/mL) and total iodine uptake (mg) were calculated using prototype software in the early (arterial) and late (venous) post-contrast circulatory phase in 110 mediastinal lymph nodes. The arterial enhancement fraction (AEF) was calculated and compared with lymph node size and response to chemotherapy. A significant difference of AEF was observed between enlarged (90.4 %; 32.3-238.5 %) and non-enlarged (72.7 %; -37.5-237.5 %) lymph nodes (p = 0.044) before treatment onset. A significantly different change of AEF in responding (decrease of 26.3 %; p = 0.022) and non-responding (increase of 43.0 %; p = 0.031) lymph nodes was demonstrated. A higher value of AEF before treatment was observed in lymph nodes with subsequent favourable response (88.6 % vs. 77.7 %; p = 0.122), but this difference did not reach statistical significance. The dual-phase DE-CT examination with quantification of ratio of early and late post-contrast iodine uptake is a feasible and promising method for the functional evaluation of mediastinal lymph nodes including therapy response assessment. (orig.)

  12. CREATION OF THE MODEL ADDITIONAL PROTOCOL

    Energy Technology Data Exchange (ETDEWEB)

    Houck, F.; Rosenthal, M.; Wulf, N.

    2010-05-25

    In 1991, the international nuclear nonproliferation community was dismayed to discover that the implementation of safeguards by the International Atomic Energy Agency (IAEA) under its NPT INFCIRC/153 safeguards agreement with Iraq had failed to detect Iraq's nuclear weapon program. It was now clear that ensuring that states were fulfilling their obligations under the NPT would require not just detecting diversion but also the ability to detect undeclared materials and activities. To achieve this, the IAEA initiated what would turn out to be a five-year effort to reappraise the NPT safeguards system. The effort engaged the IAEA and its Member States and led to agreement in 1997 on a new safeguards agreement, the Model Protocol Additional to the Agreement(s) between States and the International Atomic Energy Agency for the Application of Safeguards. The Model Protocol makes explicit that one IAEA goal is to provide assurance of the absence of undeclared nuclear material and activities. The Model Protocol requires an expanded declaration that identifies a State's nuclear potential, empowers the IAEA to raise questions about the correctness and completeness of the State's declaration, and, if needed, allows IAEA access to locations. The information required and the locations available for access are much broader than those provided for under INFCIRC/153. The negotiation was completed in quite a short time because it started with a relatively complete draft of an agreement prepared by the IAEA Secretariat. This paper describes how the Model Protocol was constructed and reviews key decisions that were made both during the five-year period and in the actual negotiation.

  13. The Impact of Carrot Enriched in Iodine through Soil Fertilization on Iodine Concentration and Selected Biochemical Parameters in Wistar Rats

    OpenAIRE

    Ewa Piątkowska; Aneta Kopeć; Renata Bieżanowska-Kopeć; Mirosław Pysz; Joanna Kapusta-Duch; Aneta Agnieszka Koronowicz; Sylwester Smoleń; Łukasz Skoczylas; Iwona Ledwożyw-Smoleń; Roksana Rakoczy; Edyta Maślak

    2016-01-01

    Iodine is one of the trace elements which are essential for mammalian life. The major objective of iodine biofortification of plants is to obtain food rich in this trace element, which may increase its consumption by various populations. Additionally, it may reduce the risk of iodine deficiency diseases. In this research for the first time we have assessed the bioavailability of iodine from raw or cooked carrot biofortified with this trace element on iodine concentration in selected tissues a...

  14. Antineoplastic mechanisms of Iodine in cancers that take up Iodine

    Directory of Open Access Journals (Sweden)

    Carmen Aceves

    2015-12-01

    Full Text Available Purpose: In addition to being a component of thyroid hormone (TH, iodine can be an antioxidant as well as an antiproliferative and differentiation agent that helps to maintain the integrity of several organs with the ability to take up iodine.Methods and Results: Studies from our laboratory shown that in preclinical (cell culture, induced animal cancer and xenographs and clinical studies (mammary cancer protocol, molecular iodine (I2 supplementation exerts suppressive effects on implantation, development, and progression of cancer neoplasias. These effects can be mediated by a variety of mechanisms and pathways, including direct actions, in which the oxidized iodine modulates the immune/tumor response and through iodolipid formation and the activation of peroxisome proliferator-activated receptors type gamma (PPARγ triggering apoptotic and/or differentiation pathways.Conclusion: The absence of side effects and the easy availability and handling of I2 have allowed the establishment of clinical protocols to utilize I2 supplementation as an adjuvant in therapies against cancers that take up iodine.-----------------------------------------Cite this article as:  Aceves C, Anguiano B. Antineoplastic mechanisms of Iodine in cancers that take up Iodine. Int J Cancer Ther Oncol 2015; 3(4:3401.[This abstract was presented at the BIT’s 8th Annual World Cancer Congress, which was held from May 15-17, 2015 in Beijing, China.

  15. Consuming iodine enriched eggs to solve the iodine deficiency endemic for remote areas in Thailand

    OpenAIRE

    Teeyapant Punthip; Srijantr Pongsant; Charoensiriwatana Wiyada; Wongvilairattana Jintana

    2010-01-01

    Abstract Background Evidence showed that the occurrence of iodine deficiency endemic areas has been found in every provinces of Thailand. Thus, a new pilot programme for elimination of iodine deficiency endemic areas at the community level was designed in 2008 by integrating the concept of Sufficient Economic life style with the iodine biofortification of nutrients for community consumption. Methods A model of community hen egg farm was selected at an iodine deficiency endemic area in North E...

  16. Iodine in drinking water varies by more than 100-fold in Denmark. Importance for iodine content of infant formulas.

    Science.gov (United States)

    Pedersen, K M; Laurberg, P; Nohr, S; Jorgensen, A; Andersen, S

    1999-05-01

    The iodine intake level of the population is of major importance for the occurrence of thyroid disorders in an area. The aim of the present study was to evaluate the importance of drinking water iodine content for the known regional differences in iodine intake in Denmark and for the iodine content of infant formulas. Iodine in tap water obtained from 55 different locations in Denmark varied from 139 microg/l. In general the iodine content was low in Jutland (median 4.1 microg/l) with higher values on Sealand (23 microg/l) and other islands. Preparation of coffee or tea did not reduce the iodine content of tap water with a high initial iodine concentration. A statistically significant correlation was found between tap water iodine content today and the urinary iodine excretion measured in 41 towns in 1967 (r=0.68, Piodine excretion in Denmark of 43 microg/24h excluding iodine in water and a daily water intake of 1.7 l. The iodine content of infant formulas prepared by addition of demineralized water varied from 37 to 138 microg/l (median 57 microg/l, n=18). Hence the final iodine content would depend heavily on the source of water used for preparation. We found that iodine in tap water was a major determinant of regional differences in iodine intake in Denmark. Changes in water supply and possibly water purification methods may influence the population iodine intake level and the occurrence of thyroid disorders.

  17. Modeling Threshold of Stress Intensity Factor in Iodine Induced Stress Corrosion Crack of Zirconium

    Institute of Scientific and Technical Information of China (English)

    SHANG; Xin-yuan; CHEN; Peng

    2013-01-01

    KISCC,which is the threshold of stress intensity factor of iodine induced stress corrosion crack(ISCC)of Zirconium,reflects the susceptibility of ISCC of zirconium.Once the stress intensity factor surpasses the threshold,the cracking propagation modality in material will transform to transgranular from intergranular immediately and the velocity of the cracking will increase rapidly.Four key factors that’s

  18. Thermodynamic modeling of HIx part of the Iodine – Sulfur thermocycle

    OpenAIRE

    Hadj-Kali, Mohamed; Gerbaud, Vincent; Borgard, Jean-Marc; Floquet, Pascal; Joulia, Xavier; Carles, Philippe

    2007-01-01

    The thermochemical water splitting cycle is an environmentally attractive way to produce hydrogen without using fossil fuels. Among a hundreds possible cycles, the sulfur – iodine (IS) is a promising one, expected to become a major source of hydrogen production from nuclear or solar energy. The IS process cycle is divided into three sections; namely: (1) the Bunsen section whose purpose is to produce the two immiscible liquid acid phases: one containing mainly sulfuric acid and the other h...

  19. Role of iodine in pathogenesis of thyroid disease - is induction of apoptosis consequence of iodine cytotoxicity?

    Directory of Open Access Journals (Sweden)

    Marković Ljiljana

    2017-01-01

    Full Text Available Iodine is one of the best-characterized environmental factors associated with autoimmune thyroid disease (ATD. Epidemiological studies have shown that ATD incidence has increased following the introduction of salt iodination in the 1920s; in addition, ATD patients can improve upon iodine restriction. In animal models such as BioBreeding/Worcester and Buffalo rats, obese chicken strain, and non-obese diabetic H-2h4 mice, excess iodine is associated with autoimmunity. Analyses of Hashimoto thyroiditis (HT have shown enlarged number of apoptotic follicular cells, and the destruction is an effect of death receptormediated apoptosis. Excess of iodine induces rapid apoptosis of goitrogen Wistar pretreated rats, possibly connected with inhibition of polyamine synthesis, inhibitors of DNA fragmentation. Percentage of apoptotic cells was statistically higher in patients with HT than in those with euthyroid goiter, with significant increase of caspase 32. Genes for Bcl-2 and Bax proteins are under the transcriptional control of p53. In TAD-2 cell cultures, apoptosis is p53-independed, suggesting that DNA damage is not primarily evoked by potassium iodide (KI. High concentrations of NaI increase the proportion of apoptotic cells in FTRL5 thyroid cell line. Iodide cytotoxicity is inhibited by a TPO inhibitor and is relieved with an anti-oxidant agent. Chronic iodine excess induces apoptosis and necrosis of thyroid follicular and endothelial cells, leading to thyroglobulin accumulation in connective tissue. Iodide excess requires peroxidase enzymatic activity to induce apoptosis. Ionic iodide is not directly toxic, whereas its molecular form I2 mediates the apoptotic effect of KI. [Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. OI-175059

  20. Reduced dimer production in solar-simulator-pumped continuous wave iodine lasers based on model simulations and scaling and pumping studies

    Science.gov (United States)

    Costen, Robert C.; Heinbockel, John H.; Miner, Gilda A.; Meador, Willard E., Jr.; Tabibi, Bagher M.; Lee, Ja H.; Williams, Michael D.

    1995-01-01

    A numerical rate equation model for a continuous wave iodine laser with longitudinally flowing gaseous lasant is validated by approximating two experiments that compare the perfluoroalkyl iodine lasants n-C3F7I and t-C4F9I. The salient feature of the simulations is that the production rate of the dimer (C4F9)2 is reduced by one order of magnitude relative to the dimer (C3F7)2. The model is then used to investigate the kinetic effects of this reduced dimer production, especially how it improves output power. Related parametric and scaling studies are also presented. When dimer production is reduced, more monomer radicals (t-C4F9) are available to combine with iodine ions, thus enhancing depletion of the laser lower level and reducing buildup of the principal quencher, molecular iodine. Fewer iodine molecules result in fewer downward transitions from quenching and more transitions from stimulated emission of lasing photons. Enhanced depletion of the lower level reduces the absorption of lasing photons. The combined result is more lasing photons and proportionally increased output power.

  1. Modelling transport and deposition of caesium and iodine from the Chernobyl accident using the DREAM model

    Directory of Open Access Journals (Sweden)

    J. Brandt

    2002-06-01

    Full Text Available A tracer model, DREAM (the Danish Rimpuff and Eulerian Accidental release Model, has been developed for modelling transport, dispersion and deposition (wet and dry of radioactive material from accidental releases, as the Chernobyl accident. The model is a combination of a Lagrangian model, that includes the near source dispersion, and an Eulerian model describing the long-range transport. The performance of the transport model has previously been tested within the European Tracer Experiment, ETEX, which included transport and dispersion of an inert, non-depositing tracer from a controlled release. The focus of this paper is the model performance with respect to the deposition of 137Cs, 134Cs and 131I from the Chernobyl accident, using different relatively simple and comprehensive parameterizations. The performance, compared to measurements, of different combinations of parameterizations of wet and dry deposition schemes has been evaluated, using different statistical tests.

  2. Iodine speciation in aerosol particle samples collected over the sea between offshore China and the Arctic Ocean

    Institute of Scientific and Technical Information of China (English)

    KANG Hui; XU Siqi; YU Xiawei; LI Bing; LIU Wei; YANG Hongxia; XIE Zhouqing

    2015-01-01

    Iodine species collected by an onboard PM10 particle sampling system during the Second Chinese National Arctic Research Expedition (July–September 2003) were measured using inductively coupled plasma mass spectrometry and ion chromatography-inductively coupled plasma mass spectrometry. Iodine (I−) was detected in all samples over the Arctic Ocean, whereas additional iodine species including insoluble iodine, soluble organic iodine plus I− were detected over the northwestern Paciifc Ocean. The results suggest that the main form of iodine is different within the Arctic Ocean than it is outside. Enrichment factor values showed moderate enrichment of iodine in the northwestern Paciifc, whereas a high enrichment factor was found in polar regions, implying sources other than sea salt. A potential explanation was ascribed to the role of sea ice melt in the Arctic and rapid growth of algae in seawater, which enhances the production of iodocarbon and air-sea exchange. This was conifrmed by the larger values of total iodine in 2008 than in 2003, with greater sea ice melt in the former year. In comparison with earlier reports, ratios of iodate to iodide (IO3−/I−) were much smaller than 1.0. These ratios were also different from modeling results, implying more complicated cycles of atmospheric iodine than are presently understood.

  3. Geochemical Cycling of Iodine Species in Soils

    Energy Technology Data Exchange (ETDEWEB)

    Hu, Q; Moran, J E; Blackwood, V

    2007-08-23

    Iodine is an important element in studies of environmental protection and human health, global-scale hydrologic processes and nuclear nonproliferation. Biogeochemical cycling of iodine in soils is complex, because iodine occurs in multiple oxidation states and as inorganic and organic species that may be hydrophilic, atmophilic, and biophilic. In this study, we applied new analytical techniques to study the content and speciation of stable iodine in representative surface soils, and sorption and transport behavior of iodine species (iodide, iodate, and 4-iodoaniline) in sediments collected at numerous nuclear facilities in the United States, where anthropogenic {sup 129}I from prior nuclear fuel processing activities poses an environmental risk. The surface soil samples were chosen for their geographic locations (e.g., near the ocean or nuclear facilities) and for their differing physico-chemical characteristics (organic matter, texture, etc). Extracted solutions were analyzed by IC and ICP-MS methods to determine iodine concentrations and to examine iodine speciation (iodide, iodate, and organic iodine). In natural soils, iodine is mostly (nearly 90% of total iodine) present as organic species, while inorganic iodine becomes important (up to 50%) only in sediments with low organic matter. Results from laboratory column studies, aimed at examining transport of different iodine species, showed much greater retardation of 4-iodoaniline than iodide or iodate. Careful attention must be given to potential interconversion among species when interpreting the biogeochemical behavior of iodine in the environment. In addition to speciation, input concentration and residence time effects will influence the biogeochemical cycling of anthropogenic 129I deposited on surface soils.

  4. Geochemical Cycling of Iodine Species in Soils

    Energy Technology Data Exchange (ETDEWEB)

    Hu, Q; Moran, J E; Blackwood, V

    2007-08-23

    Iodine is an important element in studies of environmental protection and human health, global-scale hydrologic processes and nuclear nonproliferation. Biogeochemical cycling of iodine in soils is complex, because iodine occurs in multiple oxidation states and as inorganic and organic species that may be hydrophilic, atmophilic, and biophilic. In this study, we applied new analytical techniques to study the content and speciation of stable iodine in representative surface soils, and sorption and transport behavior of iodine species (iodide, iodate, and 4-iodoaniline) in sediments collected at numerous nuclear facilities in the United States, where anthropogenic {sup 129}I from prior nuclear fuel processing activities poses an environmental risk. The surface soil samples were chosen for their geographic locations (e.g., near the ocean or nuclear facilities) and for their differing physico-chemical characteristics (organic matter, texture, etc). Extracted solutions were analyzed by IC and ICP-MS methods to determine iodine concentrations and to examine iodine speciation (iodide, iodate, and organic iodine). In natural soils, iodine is mostly (nearly 90% of total iodine) present as organic species, while inorganic iodine becomes important (up to 50%) only in sediments with low organic matter. Results from laboratory column studies, aimed at examining transport of different iodine species, showed much greater retardation of 4-iodoaniline than iodide or iodate. Careful attention must be given to potential interconversion among species when interpreting the biogeochemical behavior of iodine in the environment. In addition to speciation, input concentration and residence time effects will influence the biogeochemical cycling of anthropogenic 129I deposited on surface soils.

  5. Modelling transport and deposition of caesium and iodine from the Chernobyl accident using the DREAM model

    Directory of Open Access Journals (Sweden)

    J. Brandt

    2002-01-01

    Full Text Available A tracer model, DREAM (the Danish Rimpuff and Eulerian Accidental release Model, has been developed for modelling transport, dispersion and deposition (wet and dry of radioactive material from accidental releases, as the Chernobyl accident. The model is a combination of a Lagrangian model, that includes the near source dispersion, and an Eulerian model describing the long-range transport. The performance of the transport model has previously been tested within the European Tracer Experiment, ETEX, which included transport and dispersion of an inert, non-depositing tracer from a controlled release. The focus of this paper is the model performance with respect to the total deposition of  137Cs, 134Cs and 131I from the Chernobyl accident, using different relatively simple and comprehensive parameterizations for dry- and wet deposition. The performance, compared to measurements, of using different combinations of two different wet deposition parameterizations and three different parameterizations of dry deposition has been evaluated, using different statistical tests. The best model performance, compared to measurements, is obtained when parameterizing the total deposition combined of a simple method for dry deposition and a subgrid-scale averaging scheme for wet deposition based on relative humidities. The same major conclusion is obtained for all the three different radioactive isotopes and using two different deposition measurement databases. Large differences are seen in the results obtained by using the two different parameterizations of wet deposition based on precipitation rates and relative humidities, respectively. The parameterization based on subgrid-scale averaging is, in all cases, performing better than the parameterization based on precipitation rates. This indicates that the in-cloud scavenging process is more important than the below cloud scavenging process for the submicron particles and that the precipitation rates are

  6. Consuming iodine enriched eggs to solve the iodine deficiency endemic for remote areas in Thailand

    Directory of Open Access Journals (Sweden)

    Teeyapant Punthip

    2010-12-01

    Full Text Available Abstract Background Evidence showed that the occurrence of iodine deficiency endemic areas has been found in every provinces of Thailand. Thus, a new pilot programme for elimination of iodine deficiency endemic areas at the community level was designed in 2008 by integrating the concept of Sufficient Economic life style with the iodine biofortification of nutrients for community consumption. Methods A model of community hen egg farm was selected at an iodine deficiency endemic area in North Eastern part of Thailand. The process for the preparation of high content iodine enriched hen food was demonstrated to the farm owner with technical transfer in order to ensure the sustainability in the long term for the community. The iodine content of the produced iodine enriched hen eggs were determined and the iodine status of volunteers who consumed the iodine enriched hen eggs were monitored by using urine iodine excretion before and after the implement of iodine enrichment in the model farm. Results The content of iodine in eggs from the model farm were 93.57 μg per egg for the weight of 55 - 60 g egg and 97.76 μg for the weight of 60 - 65 g egg. The biological active iodo-organic compounds in eggs were tested by determination of the base-line urine iodine of the volunteer villagers before and after consuming a hard boiled iodine enriched egg per volunteer at breakfast for five days continuous period in 59 volunteers of Ban Kew village, and 65 volunteers of Ban Nong Nok Kean village. The median base-line urine iodine level of the volunteers in these two villages before consuming eggs were 7.00 and 7.04 μg/dL respectively. After consuming iodine enriched eggs, the median urine iodine were raised to the optimal level at 20.76 μg/dL for Ban Kew and 13.95 μg/dL for Ban Nong Nok Kean. Conclusions The strategic programme for iodine enrichment in the food chain with biological iodo-organic compound from animal origins can be an alternative method to

  7. Model averaging for semiparametric additive partial linear models

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    To improve the prediction accuracy of semiparametric additive partial linear models(APLM) and the coverage probability of confidence intervals of the parameters of interest,we explore a focused information criterion for model selection among ALPM after we estimate the nonparametric functions by the polynomial spline smoothing,and introduce a general model average estimator.The major advantage of the proposed procedures is that iterative backfitting implementation is avoided,which thus results in gains in computational simplicity.The resulting estimators are shown to be asymptotically normal.A simulation study and a real data analysis are presented for illustrations.

  8. Modelling protection behaviour towards micronutrient deficiencies: case of iodine biofortified vegetable legumes as health intervention for school-going children

    OpenAIRE

    Mogendi, Joseph Birundu; De Steur, Hans; Gellynck, Xavier; Makokha, Anselimo

    2016-01-01

    BACKGROUND/OBJECTIVES: Despite successes recorded in combating iodine deficiency, more than 2 billion people are still at risk of iodine deficiency disorders. Rural landlocked and mountainous areas of developing countries are the hardest hit, hence the need to explore and advance novel strategies such as biofortification. SUBJECTS/METHODS: We evaluated adoption, purchase, and consumption of iodine biofortified vegetable legumes (IBVL) using the theory of protection motivations (PMT) integ...

  9. Iodine-125 Seeds Strand for Treatment of Tumor Thrombus in Inferior Vena Cava: An Experimental Study in a Rabbit Model

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Wen, E-mail: wenzhangxiao@126.com; Yan, Zhiping, E-mail: Yan.zhiping@zs-hospital.sh.cn; Luo, Jianjun, E-mail: luo.jianjun@zs-hospital.sh.cn; Fang, Zhuting, E-mail: 470389481@qq.com; Wu, Linlin, E-mail: linlinzhifubao@126.com; Liu, QingXin, E-mail: liu.qingxin@zs-hospital.sh.cn; Qu, Xudong, E-mail: qu.xudong@zs-hospital.sh.cn; Liu, Lingxiao, E-mail: liu.lingxiao@zs-hospital.sh.cn; Wang, Jianhua, E-mail: wang.jianhua@zs-hospital.sh.cn [Fudan University, Department of Interventional Radiology, Zhongshan Hospital (China)

    2013-10-15

    Objective: The purpose of this study was to establish an animal model of implanted inferior vena cava tumor thrombus (IVCTT) and to evaluate the effect of linear iodine-125 seeds strand in treating implanted IVCTT. Methods: Tumor cell line VX{sub 2} was inoculated subcutaneously into New Zealand rabbit to develop the parent tumor. The tumor strip was inoculated into inferior vena cava (IVC) to establish the IVCTT model. The IVCTT was confirmed by multidetector computed tomography (MDCT) after 2 weeks. Twelve rabbits with IVCTT were randomly divided into two groups. Treatment group (group T; n = 6) underwent Iodine-125 seeds brachytherapy, and the control group (group C; n = 6) underwent blank seeds strand. The blood laboratory examination (including blood routine examination, hepatic and renal function), body weight, survival time, and IVCTT volume by MDCT were monitored. All rabbits were dissected postmortem, and the therapeutic effects were evaluated on the basis of histopathology. The proliferating cell nuclear antigen index (PI) and apoptosis index (AI) of IVCTT were compared between two groups. T test, Wilcoxon rank test, and Kaplan-Meier survival curve analysis were used. Results: The success rate of establishing IVCTT was 100 %. The body weight loss and cachexia of rabbits in group C appeared earlier than in group T. Body weight in the third week, the mean survival time, PI, AI in groups T and C were 2.23 {+-} 0.12 kg, 57.83 {+-} 8.68 days, (16.73 {+-} 5.18 %), (29.47 {+-} 7.18 %), and 2.03 {+-} 0.13 kg, 43.67 {+-} 5.28 days, (63.01 {+-} 2.01 %), (6.02 {+-} 2.93 %), respectively. There were statistically significant differences between group T and group C (P < 0.05). The IVCTT volume of group T was remarkably smaller than that of group C. Conclusions: Injecting and suspensory fixing VX2 tumor strip into IVC is a reliable method to establish IVCTT animal model. The linear Iodine-125 seeds strand brachytherapy was a safe and effective method for treating IVCTT

  10. A DNA based model for addition computation

    Institute of Scientific and Technical Information of China (English)

    GAO Lin; YANG Xiao; LIU Wenbin; XU Jin

    2004-01-01

    Much effort has been made to solve computing problems by using DNA-an organic simulating method, which in some cases is preferable to the current electronic computer. However, No one at present has proposed an effective and applicable method to solve addition problem with molecular algorithm due to the difficulty in solving the carry problem which can be easily solved by hardware of an electronic computer. In this article, we solved this problem by employing two kinds of DNA strings, one is called result and operation string while the other is named carrier. The result and operation string contains some carry information by its own and denotes the ultimate result while the carrier is just for carrying use. The significance of this algorithm is the original code, the fairly easy steps to follow and the feasibility under current molecular biological technology.

  11. Comparison of iodinated contrast media for the assessment of atherosclerotic plaque attenuation values by CT coronary angiography: Observations in an ex vivo model

    NARCIS (Netherlands)

    L. la Grutta (Ludovico); M. Galia (Massimo); G. Gentile; G. Lo Re (G.); E. Grassedonio (Emanuele); F. Coppolino; E. Maffei (Erica); E. Maresi (E.); A. Lo Casto (A.); F. Cademartiri (Filippo); M. Midiri (Massimo)

    2013-01-01

    textabstractObjective: To compare the influence of different iodinated contrast media with several dilutions on plaque attenuation in an ex vivo coronary model studied by multislice CT coronary angiography. Methods: In six ex vivo left anterior descending coronary arteries immersed in oil, CT (slice

  12. Development and internal validation of a multivariable prediction model for biochemical failure after whole-gland salvage iodine-125 prostate brachytherapy for recurrent prostate cancer

    NARCIS (Netherlands)

    Peters, M; van der Voort van Zyp, J R N; Moerland, M A; Hoekstra, C J; van de Pol, S; Westendorp, H; Maenhout, M; Kattevilder, R; Verkooijen, H M; van Rossum, P S N; Ahmed, H U; Shah, T T; Emberton, M; van Vulpen, M

    2016-01-01

    BACKGROUND: Localized recurrent prostate cancer after primary radiotherapy can be curatively treated using salvage iodine-125 ((125)I) brachytherapy. Selection is hampered by a lack of predictive factors for cancer control. This study aims to develop and internally validate a prognostic model for bi

  13. Dietary Iodine Intake of the Australian Population after Introduction of a Mandatory Iodine Fortification Programme.

    Science.gov (United States)

    Charlton, Karen; Probst, Yasmine; Kiene, Gabriella

    2016-11-04

    To address mild iodine deficiency in Australia, a mandatory fortification program of iodised salt in bread was implemented in 2009. This study aimed to determine factors associated with achieving an adequate dietary iodine intake in the Australian population post-fortification, and to assess whether bread consumption patterns affect iodine intake in high-risk groups. Using nationally representative data of repeated 24-h dietary recalls from the 2011-2012 Australian National Nutrition and Physical Activity Survey, dietary iodine intakes and food group contributions were compared by age, socioeconomic status (SES), and geographical remoteness (N = 7735). The association between fortified bread intake and adequacy of iodine intake (meeting age and sex-specific Estimated Average Requirements) was investigated using logistic regression models in women of childbearing age 14-50 years (n = 3496) and children aged 2-18 years (n = 1772). The effect of SES on bread consumption was further investigated in a sub group of children aged 5-9 years (n = 488). Main sources of iodine intake at the time of the survey were cereal and cereal products, followed by milk products and dishes. Differences in iodine intake and dietary iodine habits according to age, SES and location were found (p iodine intake (OR 5.0, 95% CI 4.96-5.13; p iodine intake exist within sectors of the Australian population, even after mandatory fortification of a staple food. On-going monitoring and surveillance of iodine status is required.

  14. Oxygen discharge and post-discharge kinetics experiments and modeling for the electric oxygen-iodine laser system.

    Science.gov (United States)

    Palla, A D; Zimmerman, J W; Woodard, B S; Carroll, D L; Verdeyen, J T; Lim, T C; Solomon, W C

    2007-07-26

    Laser oscillation at 1315 nm on the I(2P1/2)-->I(2P3/2) transition of atomic iodine has been obtained by a near resonant energy transfer from O2(a1Delta) produced using a low-pressure oxygen/helium/nitric oxide discharge. In the electric discharge oxygen-iodine laser (ElectricOIL) the discharge production of atomic oxygen, ozone, and other excited species adds levels of complexity to the singlet oxygen generator (SOG) kinetics which are not encountered in a classic purely chemical O2(a1Delta) generation system. The advanced model BLAZE-IV has been introduced to study the energy-transfer laser system dynamics and kinetics. Levels of singlet oxygen, oxygen atoms, and ozone are measured experimentally and compared with calculations. The new BLAZE-IV model is in reasonable agreement with O3, O atom, and gas temperature measurements but is under-predicting the increase in O2(a1Delta) concentration resulting from the presence of NO in the discharge and under-predicting the O2(b1Sigma) concentrations. A key conclusion is that the removal of oxygen atoms by NOX species leads to a significant increase in O2(a1Delta) concentrations downstream of the discharge in part via a recycling process; however, there are still some important processes related to the NOX discharge kinetics that are missing from the present modeling. Further, the removal of oxygen atoms dramatically inhibits the production of ozone in the downstream kinetics.

  15. Injection of iodine to the stratosphere

    Science.gov (United States)

    Saiz-Lopez, Alfonso; Baidar, Sunil; Cuevas, Carlos A.; Koening, Theodore; Fernandez, Rafael P.; Dix, Barbara; Kinnison, Douglas E.; Lamarque, Jean-Francois; Rodriguez-Lloveras, Xavier; Campos, Teresa L.; Volkamer, Rainer

    2016-04-01

    There are still many uncertainties about the influence of iodine chemistry in the stratosphere, as the real amount of reactive iodine injected to this layer the troposphere and the partitioning of iodine species are still unknown. In this work we report a new estimation of the injection of iodine into the stratosphere based on novel daytime (SZA layer (TORERO campaign) and a 3D global chemistry-climate model (CAM-Chem) with the most recent knowledge about iodine photochemistry. The results indicate that significant levels of total reactive iodine (0.25-0.7 pptv), between 2 and 5 times larger than the accepted upper limits, could be injected into the stratosphere via tropical convective outflow. At these iodine levels, modelled iodine catalytic cycles account for up to 30% of the contemporary ozone loss in the tropical lower stratosphere and can exert a stratospheric ozone depletion potential equivalent or even larger than that of very short-lived bromocarbons. Therefore, we suggest that iodine sources and chemistry need to be considered in assessments of the historical and future evolution of the stratospheric ozone layer.

  16. Deep Bed Iodine Sorbent Testing FY 2011 Report

    Energy Technology Data Exchange (ETDEWEB)

    Nick Soelberg; Tony Watson

    2011-08-01

    Nuclear fission results in the production of fission products (FPs) and activation products that increasingly interfere with the fission process as their concentrations increase. Some of these fission and activation products tend to evolve in gaseous species during used nuclear fuel reprocessing. Analyses have shown that I129, due to its radioactivity, high potential mobility in the environment, and high longevity (half life of 15.7 million years), can require control efficiencies of up to 1,000x or higher to meet regulatory emission limits. Deep-bed iodine sorption testing has been done to evaluate the performance of solid sorbents for capturing iodine in off-gas streams from nuclear fuel reprocessing plants. The objectives of the FY 2011 deep bed iodine sorbent testing are: (1) Evaluate sorbents for iodine capture under various conditions of gas compositions and operating temperature (determine sorption efficiencies, capacities, and mass transfer zone depths); and (2) Generate data for dynamic iodine sorption modeling. Three tests performed this fiscal year on silver zeolite light phase (AgZ-LP) sorbent are reported here. Additional tests are still in progress and can be reported in a revision of this report or a future report. Testing was somewhat delayed and limited this year due to initial activities to address some questions of prior testing, and due to a period of maintenance for the on-line GC. Each test consisted of (a) flowing a synthetic blend of gases designed to be similar to an aqueous dissolver off-gas stream over the sorbent contained in three separate bed segments in series, (b) measuring each bed inlet and outlet gas concentrations of iodine and methyl iodide (the two surrogates of iodine gas species considered most representative of iodine species expected in dissolver off-gas), (c) operating for a long enough time to achieve breakthrough of the iodine species from at least one (preferably the first two) bed segments, and (d) post-test purging

  17. Development of computational models for the simulation of isodose curves on dosimetry films generated by iodine-125 brachytherapy seeds

    Energy Technology Data Exchange (ETDEWEB)

    Santos, Adriano M.; Meira-Belo, Luiz C.; Reis, Sergio C.; Grynberg, Suely E., E-mail: amsantos@cdtn.b [Center for Development of Nuclear Technology (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)

    2011-07-01

    The interstitial brachytherapy is one modality of radiotherapy in which radioactive sources are placed directly in the region to be treated or close to it. The seeds that are used in the treatment of prostate cancer are generally cylindrical radioactive sources, consisting of a ceramic or metal matrix, which acts as the carrier of the radionuclide and as the X-ray marker, encapsulated in a sealed titanium tube. This study aimed to develop a computational model to reproduce the film-seed geometry, in order to obtain the spatial regions of the isodose curves produced by the seed when it is put over the film surface. The seed modeled in this work was the OncoSeed 6711, a sealed source of iodine-125, which its isodose curves were obtained experimentally in previous work with the use of dosimetric films. For the films modeling, compositions and densities of the two types of dosimetric films were used: Agfa Personal Monitoring photographic film 2/10, manufactured by Agfa-Geavaert; and the model EBT radiochromic film, by International Specialty Products. The film-seed models were coupled to the Monte Carlo code MCNP5. The results obtained by simulations showed to be in good agreement with experimental results performed in a previous work. This indicates that the computational model can be used in future studies for other seeds models. (author)

  18. Quantification of Iodine Supply: Representative Data on Intake and Urinary Excretion of Iodine from the German Population in 1996

    OpenAIRE

    Manz, Friedrich; Böhmer, Thomas; Gärtner, Roland; Grossklaus, Rolf; Klett, Martin; Schneider, Roland

    2002-01-01

    Background/Methods: In Germany, iodine deficiency is common. In a representative group of 2,500 Germans (age >13 years), using a specially designed food questionnaire, the iodine intake was calculated. In addition, iodine and creatinine concentrations in spot urine samples were determined in three groups with a possibly increased risk of iodine deficiency (769 conscripts, 886 pairs of mothers and newborns) or future hyperthyroidism (574 adults, age range 50-70 years) from 26 representative re...

  19. Iodine behaviour in severe accidents

    Energy Technology Data Exchange (ETDEWEB)

    Dutton, L.M.C.; Grindon, E.; Handy, B.J.; Sutherland, L. [NNC Ltd., Knutsford (United Kingdom); Bruns, W.G.; Sims, H.E. [AEA Technology, Harwell (United Kingdom); Dickinson, S. [AEA Technology, Winfrith (United Kingdom); Hueber, C.; Jacquemain, D. [IPSN/CEA, Cadarache, Saint Paul-Lez-Durance (France)

    1996-12-01

    A description is given of analyses which identify which aspects of the modelling and data are most important in evaluating the release of radioactive iodine to the environment following a potential severe accident at a PWR and which identify the major uncertainties which affect that release. Three iodine codes are used namely INSPECT, IODE and IMPAIR, and their predictions are compared with those of the PSA code MAAP. INSPECT is a mechanistic code which models iodine behaviour in the aqueous aerosol, spray water and sump water, and the partitioning of volatile species between the aqueous phases and containment gas space. Organic iodine is not modelled. IODE and IMPAIR are semi-empirical codes which do not model iodine behaviour in the aqueous aerosol, but model organic iodine. The fault sequences addressed are based on analyses for the Sizewell `B` design. Two types of sequence have been analysed.: (a) those in which a major release of fission products from the primary circuit to the containment occur, e.g. a large LOCAS, (b) those where the release by-passes the containment, e.g. a leak into the auxiliary building. In the analysis of the LOCA sequences where the pH of the sump is controlled to be a value of 8 or greater, all three codes predict that the oxidation of iodine to produce gas phase species does not make a significant contribution to the source term due to leakage from the reactor building and that the latter is dominated by iodide in the aerosol. In the case where the pH of the sump is not controlled, it is found that the proportion of gas phase iodine increases significantly, although the cumulative leakage predicted by all three codes is not significantly different from that predicted by MAAP. The radiolytic production of nitric acid could be a major factor in determining the pH, and if the pH were reduced, the codes predict an increase in gas phase iodine species leaked from the containment. (author) 4 figs., 7 tabs., 13 refs.

  20. Chalcogenide aerogels as sorbents for radioactive iodine

    Energy Technology Data Exchange (ETDEWEB)

    Subrahmanyam, Kota S.; Sarma, Debajit; Malliakas, Christos; Polychronopoulou, Kyriaki; Riley, Brian J.; Pierce, David A.; Chun, Jaehun; Kanatzidis, Mercouri G.

    2015-04-14

    Iodine (129I) is one of the radionuclides released in nuclear fuel reprocessing and poses risk to public safety due to its involvement in human metabolic processes. In order to prevent the leaching of hazardous radioactive iodine into the environment, its effective capture and sequestration is pivotal. In the context of finding a suitable matrix for capturing radioactive iodine the chalcogels, NiMoS4, CoMoS4, Sb4Sn4S12, Zn2Sn2S6, and CoSx (x = 4-5) were explored as iodine sorbents. All the chalcogels showed high uptake, reaching up to 225 mass% (2.25 g/g) of the final mass owing to strong chemical and physical iodine-chalcogen interactions. Analysis of the iodine-loaded specimens revealed that the iodine chemically reacted with Sb4Sn4S12, Zn2Sn2S6, and CoSx to form metal complexes SbI3, SnI4, and, KI respectively. The NiMoS4 and CoMoS4 chalcogels did not appear to undergo a chemical reaction with iodine since iodide complexes were not observed with these samples. Once heated, the iodine-loaded chalcogels released iodine in the temperature range of 75 °C to 220 °C, depending on the nature of iodine speciation. In the case of Sb4Sn4S12 and Zn2Sn2S6 iodine release was observed around 150 °C in the form of SnI4 and SbI3, respectively. The NiMoS4, CoMoS4, and CoSx released iodine at ~75 °C, which is consistent with physisorbed iodine. Preliminary investigations on consolidation of iodine-loaded Zn2Sn2S6 with Sb2S3 as a glass forming additive showed the content of iodine in consolidated glass ingots at around 25 mass%.

  1. Iodine and thyroid gland with or without nuclear catastrophe

    Directory of Open Access Journals (Sweden)

    Kovačev-Zavišić Branka

    2012-01-01

    Full Text Available Introduction. Iodine, as a trace element, is a necessary and limiting substrate for thyroid gland hormone synthesis. It is an essential element that enables the thyroid gland to produce thyroid hormones thyroxine (T4 and triiodothyronine (T3. Synthesis of Thyroid Hormones and Iodine Metabolism. Three iodine molecules are added to make triiodothyronine, and four for thyroxine - the two key hormones produced by the thyroid gland. Iodine deficiency. The proper daily amount of iodine is required for optimal thyroid function. Iodine deficiency can cause hypothyroidism, developmental brain disorders and goiter. Iodine deficiency is the single most common cause of preventable mental retardation and brain damage in the world. It also decreases child survival, causes goiters, and impairs growth and development. Iodine deficiency disorders in pregnant women cause miscarriages, stillbirths, and other complications. Children with iodine deficiency disorders can grow up stunted, apathetic, mentally retarded, and incapable of normal movements, speech or hearing. Excessive Iodine Intake. Excessive iodine intake, which can trigger autoimmune thyroid disease and dysfunction, is on the other side. Iodine use in Case of Nuclear Catastrophe. In addition to other severe consequences of radioactivity, high amount of radioactive iodine causes significant increase in incidence of thyroid gland carcinoma after some of the nuclear catastrophes (Hiroshima, Nagasaki, Chernobyl, Fukushima. The incidence of thyroid carcinoma was increased mostly in children. This paper was aimed at clarifying some of the possibilities of prevention according to the recommendations given by the World Health Organization.

  2. Application of Micro-Computed Tomography with Iodine Staining to Cardiac Imaging, Segmentation and Computational Model Development

    Science.gov (United States)

    Aslanidi, OV; Nikolaidou, T; Zhao, J; Smaill, BH; Gilbert, SH; Holden, AV; Lowe, T; Withers, PJ; Jarvis, JC; Stephenson, RS; Hart, G; Hancox, JC; Boyett, MR; Zhang, H

    2012-01-01

    Micro-computed tomography (micro-CT) has been widely used to generate high-resolution 3D tissue images from small animals non-destructively, especially for mineralized skeletal tissues. However, its application to the analysis of soft cardiovascular tissues has been limited by poor inter-tissue contrast. Recent ex vivo studies have shown that contrast between muscular and connective tissue in micro-CT images can be enhanced by staining with iodine. In the present study, we apply this novel technique for imaging of cardiovascular structures in canine hearts. We optimize the method to obtain high resolution X-ray micro-CT images of the canine atria and its distinctive regions - including the Bachmann’s bundle, atrioventricular node, pulmonary arteries and veins - with clear inter-tissue contrast. The imaging results are used to reconstruct and segment the detailed 3D geometry of the atria. Structure tensor analysis shows that the arrangement of atrial fibres can also be characterised using the enhanced micro-CT images, as iodine preferentially accumulates within the muscular fibres rather than in connective tissues. This novel technique can be particularly useful in non-destructive imaging of 3D cardiac architectures from large animals and humans, due to the combination of relatively high speed (~1 hour/scan of a large canine heart) and high voxel resolution (36 μm) provided. In summary, contrast micro-CT facilitates fast and non-destructive imaging and segmenting of detailed 3D cardiovascular geometries, as well as measuring fibre orientation, which are crucial in constructing biophysically detailed computational cardiac models. PMID:22829390

  3. Iodine-deficiency disorders

    NARCIS (Netherlands)

    Zimmermann, M.B.; Jooste, P.L.; Pandav, C.S.

    2008-01-01

    billion individuals worldwide have insufficient iodine intake, with those in south Asia and sub-Saharan Africa particularly affected. Iodine deficiency has many adverse effects on growth and development. These effects are due to inadequate production of thyroid hormone and are termed iodine-deficien

  4. Iodine-deficiency disorders

    NARCIS (Netherlands)

    Zimmermann, M.B.; Jooste, P.L.; Pandav, C.S.

    2008-01-01

    billion individuals worldwide have insufficient iodine intake, with those in south Asia and sub-Saharan Africa particularly affected. Iodine deficiency has many adverse effects on growth and development. These effects are due to inadequate production of thyroid hormone and are termed iodine-deficien

  5. Coordinate descent methods for the penalized semiparametric additive hazards model

    DEFF Research Database (Denmark)

    Gorst-Rasmussen, Anders; Scheike, Thomas

    . The semiparametric additive hazards model is a flexible alternative which is a natural survival analogue of the standard linear regression model. Building on this analogy, we develop a cyclic coordinate descent algorithm for fitting the lasso and elastic net penalized additive hazards model. The algorithm requires...

  6. Coordinate descent methods for the penalized semiprarametric additive hazard model

    DEFF Research Database (Denmark)

    Gorst-Rasmussen, Anders; Scheike, Thomas

    2012-01-01

    . The semiparametric additive hazards model is a flexible alternative which is a natural survival analogue of the standard linear regression model. Building on this analogy, we develop a cyclic coordinate descent algorithm for fitting the lasso and elastic net penalized additive hazards model. The algorithm requires...

  7. Further Results on Dynamic Additive Hazard Rate Model

    Directory of Open Access Journals (Sweden)

    Zhengcheng Zhang

    2014-01-01

    Full Text Available In the past, the proportional and additive hazard rate models have been investigated in the works. Nanda and Das (2011 introduced and studied the dynamic proportional (reversed hazard rate model. In this paper we study the dynamic additive hazard rate model, and investigate its aging properties for different aging classes. The closure of the model under some stochastic orders has also been investigated. Some examples are also given to illustrate different aging properties and stochastic comparisons of the model.

  8. Iodine and Selenium Biofortification with Additional Application of Salicylic Acid Affects Yield, Selected Molecular Parameters and Chemical Composition of Lettuce Plants (Lactuca sativa L. var. capitata).

    Science.gov (United States)

    Smoleń, Sylwester; Kowalska, Iwona; Czernicka, Małgorzata; Halka, Mariya; Kęska, Kinga; Sady, Włodzimierz

    2016-01-01

    Iodine (I) and selenium (Se) are included in the group of beneficial elements. They both play important roles in humans and other animals, particularly in the regulation of thyroid functioning. A substantial percentage of people around the world suffer from health disorders related to the deficiency of these elements in the diet. Salicylic acid (SA) is a compound similar to phytohormones and is known to improve the efficiency of I biofortification of plants. The influence of SA on Se enrichment of plants has not, however, been recognized together with its effect on simultaneous application of I and Se to plants. Two-year studies (2014-2015) were conducted in a greenhouse with hydroponic cultivation of lettuce in an NFT (nutrient film technique) system. They included the application of I (as KIO3), Se (as Na2SeO3) and SA into the nutrient solution. KIO3 was used at a dose of 5 mg I⋅dm(-3) (i.e., 39.4 μM I), while Na2SeO3 was 0.5 mg Se⋅dm(-3) (i.e., 6.3 μM Se). SA was introduced at three doses: 0.1, 1.0, and 10.0 mg⋅dm(-3) nutrient solutions, equivalent to 0.724, 7.24, and 72.4 μM SA, respectively. The tested combinations were as follows: (1) control, (2) I + Se, (3) I + Se + 0.1 mg SA⋅dm(-3), (4) I + Se + 1.0 mg SA⋅dm(-3) and (5) I + Se + 10.0 mg SA⋅dm(-3). The applied treatments had no significant impact on lettuce biomass (leaves and roots). Depending on the dose, a diverse influence of SA was noted with respect to the efficiency of I and Se biofortification; chemical composition of leaves; and mineral nutrition of lettuce plants, including the content of macro- and microelements and selenocysteine methyltransferase (SMT) gene expression. SA application at all tested doses comparably increased the level of selenomethionine (SeMet) and decreased the content of SA in leaves.

  9. Iodine and Selenium Biofortification with Additional Application of Salicylic Acid Affects Yield, Selected Molecular Parameters and Chemical Composition of Lettuce Plants (Lactuca sativa L. var. capitata)

    Science.gov (United States)

    Smoleń, Sylwester; Kowalska, Iwona; Czernicka, Małgorzata; Halka, Mariya; Kęska, Kinga; Sady, Włodzimierz

    2016-01-01

    Iodine (I) and selenium (Se) are included in the group of beneficial elements. They both play important roles in humans and other animals, particularly in the regulation of thyroid functioning. A substantial percentage of people around the world suffer from health disorders related to the deficiency of these elements in the diet. Salicylic acid (SA) is a compound similar to phytohormones and is known to improve the efficiency of I biofortification of plants. The influence of SA on Se enrichment of plants has not, however, been recognized together with its effect on simultaneous application of I and Se to plants. Two-year studies (2014–2015) were conducted in a greenhouse with hydroponic cultivation of lettuce in an NFT (nutrient film technique) system. They included the application of I (as KIO3), Se (as Na2SeO3) and SA into the nutrient solution. KIO3 was used at a dose of 5 mg I⋅dm-3 (i.e., 39.4 μM I), while Na2SeO3 was 0.5 mg Se⋅dm-3 (i.e., 6.3 μM Se). SA was introduced at three doses: 0.1, 1.0, and 10.0 mg⋅dm-3 nutrient solutions, equivalent to 0.724, 7.24, and 72.4 μM SA, respectively. The tested combinations were as follows: (1) control, (2) I + Se, (3) I + Se + 0.1 mg SA⋅dm-3, (4) I + Se + 1.0 mg SA⋅dm-3 and (5) I + Se + 10.0 mg SA⋅dm-3. The applied treatments had no significant impact on lettuce biomass (leaves and roots). Depending on the dose, a diverse influence of SA was noted with respect to the efficiency of I and Se biofortification; chemical composition of leaves; and mineral nutrition of lettuce plants, including the content of macro- and microelements and selenocysteine methyltransferase (SMT) gene expression. SA application at all tested doses comparably increased the level of selenomethionine (SeMet) and decreased the content of SA in leaves. PMID:27803709

  10. Iodine and Selenium Biofortification with Additional Application of Salicylic Acid Affects Yield, Selected Molecular Parameters and Chemical Composition of Lettuce Plants (Lactuca sativa L. var. capitata

    Directory of Open Access Journals (Sweden)

    Sylwester Smoleń

    2016-10-01

    Full Text Available Iodine (I and selenium (Se are included in the group of beneficial elements. They both play important roles in humans and other animals, particularly in the regulation of thyroid functioning. A substantial percentage of people around the world suffer from health disorders related to the deficiency of these elements in the diet. Salicylic acid (SA is a compound similar to phytohormones and is known to improve the efficiency of I biofortification of plants. The influence of SA on Se enrichment of plants has not, however, been recognised together with its effect on simultaneous application of I and Se to plants. Two-year studies (2014–2015 were conducted in a greenhouse with hydroponic cultivation of lettuce in an NFT (nutrient film technique system. They included the application of I (as KIO3, Se (as Na2SeO3 and SA into the nutrient solution. KIO3 was used at a dose of 5 mg I•dm-3 (i.e., 39.4 µM I, while Na2SeO3 was 0.5 mg Se•dm-3 (i.e., 6.3 µM Se. SA was introduced at three doses: 0.1, 1.0 and 10.0 mg∙dm-3 nutrient solutions, equivalent to 0.724 µM, 7.24 µM and 72.4 µM SA, respectively. The tested combinations were as follows: 1. control, 2. I + Se, 3. I + Se + 0.1 mg SA∙dm-3, 4. I + Se + 1.0 mg SA∙dm-3 and 5. I + Se + 10.0 mg SA∙dm-3. The applied treatments had no significant impact on lettuce biomass (leaves and roots. Depending on the dose, a diverse influence of SA was noted with respect to the efficiency of I and Se biofortification; chemical composition of leaves; and mineral nutrition of lettuce plants, including the content of macro- and microelements and selenocysteine methyltransferase (SMT gene expression. SA application at all tested doses comparably increased the level of selenomethionine (SeMet and decreased the content of SA in leaves.

  11. Implementation of iodine biokinetic model for interpreting I-131 contamination in breast milk after the Fukushima nuclear disaster

    Science.gov (United States)

    Tani, Kotaro; Kurihara, Osamu; Kim, Eunjoo; Yoshida, Satoshi; Sakai, Kazuo; Akashi, Makoto

    2015-07-01

    After the accident at the Fukushima Daiichi Nuclear Power Plant run by Tokyo Electric Power Company in 2011, breast milk samples obtained from volunteers living in Fukushima and neighboring prefectures were examined and small amounts of I-131 (2.2-36.3 Bq/kg) were detected in some samples. In this work, the I-131 concentrations in breast milk from nursing mothers in Ibaraki prefecture were calculated based on the iodine biokinetic model during lactation together with time-variable intake scenarios by inhalation of ambient air and ingestion of tap water, using the authors’ code. The calculated I-131 concentrations in breast milk generally agreed with those measured for the volunteers. Based on the results, thyroid equivalent doses to breast-fed infants were estimated for each place of residence of the volunteers on the assumption that these infants consumed 800 ml of breast milk every day, resulting in 10-11 mSv for Mito and Kasama cities and 1.1-1.8 mSv for Tsukuba and Moriya cities. It was suggested that breast milk consumption could be a major contributor to internal dose of breast-fed infants in areas with mild I-131 pollution; however, further studies considering personal behavior surveys would be necessary to estimate individual doses.

  12. Conceptual design model of the sulfur-iodine S-I thermochemical water splitting process for hydrogen production using nuclear heat source

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez Rodriguez, Daniel; Parra, Lazaro Garcia, E-mail: dgr@instec.cu, E-mail: lgarcia@instec.cu [Departamento de Ingenieria Nuclear, Instituto Superior de Ciencias y Tecnologias Aplicadas, La Habana (Cuba)

    2011-07-01

    Hydrogen is the most indicated candidate for its implementation as energy carrier in a future sustainable scenario. The current hydrogen production is based on fossils fuels; they have a huge contribution to the atmosphere pollution. Thermochemical water-splitting cycles do not have this issue because they use solar or nuclear heat; their environment impact is smaller than conventional fuels. The software based on chemical process simulation (CPS) can be used to simulate the thermochemical water splitting cycle Sulfur-Iodine for hydrogen production. In the paper is developed a model for Sulfur-Iodine process in order to analyze his sensibility and calculate the efficiency and the influence of many parameters on this value. (author)

  13. Iodine deficiency and iodine excess in Jiangsu Province, China

    NARCIS (Netherlands)

    Zhao, J.

    2001-01-01

    Keywords:iodine deficiency, iodine excess, endemic goiter, drinking water, iodine intake, thyroid function, thyroid size, iodized salt, iodized oil, IQ, physical development, hearing capacity, epidemiology, meta-analysis, IDD, randomized trial, intervention, USA, Bangladesh, ChinaEndemic goiter can

  14. Iodine deficiency and iodine excess in Jiangsu Province, China

    NARCIS (Netherlands)

    Zhao, J.

    2001-01-01

    Keywords:
    iodine deficiency, iodine excess, endemic goiter, drinking water, iodine intake, thyroid function, thyroid size, iodized salt, iodized oil, IQ, physical development, hearing capacity, epidemiology, meta-analysis, IDD, randomized trial, intervention, USA, Bangladesh, China

  15. Removal of volatile iodine from gas bubbles rising in water pools: review and assessment of pool scrubbing codes

    Energy Technology Data Exchange (ETDEWEB)

    Polo, J.; Herranz, L.E.; Peyres, V.; Escudero, M. [CIEMAT, Nuclear Technology Institute, Madrid (Spain)

    1996-12-01

    During a hypothetical nuclear reactor accident with core damage the fission products released from the degrading fuel bundles often pass through aqueous beds before entering the containment, mitigating in part the source term. Several computer codes have been developed for predicting the fission product and aerosols removal in pool scrubbing scenarios. In addition to particle removal, these codes simulate the retention of some volatile iodine compounds. In this work a review of volatile iodine removal models included in SPARC and BUSCA codes is presented. Besides, the results and discussions of a validation of both codes against the available experimental data are summarized. SPARC and BUSCA codes model the diffusion of iodine toward the bubble interface by using the film penetration theory, which assumes a double layer gas-liquid at the interface. However, there are some differences between the two models, mainly related to the boundary conditions in the aqueous volume for the diffusion of molecular iodine. In SPARC, a set of fast reactions in the liquid phase control both the molecular iodine concentration in the pool and the partition coefficient of iodine at the interface. Thus, the aqueous chemistry plays an important role in the boundary conditions for the diffusion process. On the contrary, the BUSCA model has no chemical considerations at all, and assumes a null iodine concentration in the water bulk. Several sensitivity studies have been made in order to weight the effect of these differences. The variables examined in these studies were the pool temperature and the incoming iodine concentration in the pool. Additionally, sensitivity studies focused on the steam mass fraction of the injected gas were performed to study the effect of the different approach of both models for the condensation process. The results showed a different sensitivity of SPARC and BUSCA to the incoming concentration. (author) 5 tabs., 26 refs.

  16. Fitting Additive Binomial Regression Models with the R Package blm

    Directory of Open Access Journals (Sweden)

    Stephanie Kovalchik

    2013-09-01

    Full Text Available The R package blm provides functions for fitting a family of additive regression models to binary data. The included models are the binomial linear model, in which all covariates have additive effects, and the linear-expit (lexpit model, which allows some covariates to have additive effects and other covariates to have logisitc effects. Additive binomial regression is a model of event probability, and the coefficients of linear terms estimate covariate-adjusted risk differences. Thus, in contrast to logistic regression, additive binomial regression puts focus on absolute risk and risk differences. In this paper, we give an overview of the methodology we have developed to fit the binomial linear and lexpit models to binary outcomes from cohort and population-based case-control studies. We illustrate the blm packages methods for additive model estimation, diagnostics, and inference with risk association analyses of a bladder cancer nested case-control study in the NIH-AARP Diet and Health Study.

  17. Coordinate descent methods for the penalized semiprarametric additive hazard model

    DEFF Research Database (Denmark)

    Gorst-Rasmussen, Anders; Scheike, Thomas

    2012-01-01

    For survival data with a large number of explanatory variables, lasso penalized Cox regression is a popular regularization strategy. However, a penalized Cox model may not always provide the best fit to data and can be difficult to estimate in high dimension because of its intrinsic nonlinearity....... The semiparametric additive hazards model is a flexible alternative which is a natural survival analogue of the standard linear regression model. Building on this analogy, we develop a cyclic coordinate descent algorithm for fitting the lasso and elastic net penalized additive hazards model. The algorithm requires...

  18. 碘酊加高渗葡萄糖水外敷联合CO2激光照射治愈慢性溃疡3例%Three Cases of Chronic Ulcer Cured by the Application of Povidone Iodine in Addition to 25% Glucose Solution and the Irradiation with Carbon-dioxide Laser Rays

    Institute of Scientific and Technical Information of China (English)

    刘玉凤

    2003-01-01

    We report three cases ofchronic ulcer on the legs,cured by the application of povidone iodine in addition to25% glucose solution and the irradiation with carbon - dioxide laser rays.These three patients cured after the treatment of 2,3,6 months respectively. We think the method safe and effective as well as the cheap price.

  19. Dietary Iodine Intake of the Australian Population after Introduction of a Mandatory Iodine Fortification Programme

    Directory of Open Access Journals (Sweden)

    Karen Charlton

    2016-11-01

    Full Text Available To address mild iodine deficiency in Australia, a mandatory fortification program of iodised salt in bread was implemented in 2009. This study aimed to determine factors associated with achieving an adequate dietary iodine intake in the Australian population post-fortification, and to assess whether bread consumption patterns affect iodine intake in high-risk groups. Using nationally representative data of repeated 24-h dietary recalls from the 2011–2012 Australian National Nutrition and Physical Activity Survey, dietary iodine intakes and food group contributions were compared by age, socioeconomic status (SES, and geographical remoteness (N = 7735. The association between fortified bread intake and adequacy of iodine intake (meeting age and sex-specific Estimated Average Requirements was investigated using logistic regression models in women of childbearing age 14–50 years (n = 3496 and children aged 2–18 years (n = 1772. The effect of SES on bread consumption was further investigated in a sub group of children aged 5–9 years (n = 488. Main sources of iodine intake at the time of the survey were cereal and cereal products, followed by milk products and dishes. Differences in iodine intake and dietary iodine habits according to age, SES and location were found (p < 0.001 for women of child-bearing age. Fortified bread consumption at ≥100 g/day was associated with five times greater odds of achieving an adequate iodine intake (OR 5.0, 95% CI 4.96–5.13; p < 0.001 compared to lower bread consumption in women and 12 times in children (OR 12.34, 95% CI 1.71–89.26; p < 0.001. Disparities in dietary iodine intake exist within sectors of the Australian population, even after mandatory fortification of a staple food. On-going monitoring and surveillance of iodine status is required.

  20. An Additive-Multiplicative Restricted Mean Residual Life Model

    DEFF Research Database (Denmark)

    Mansourvar, Zahra; Martinussen, Torben; Scheike, Thomas H.

    2016-01-01

    mean residual life model to study the association between the restricted mean residual life function and potential regression covariates in the presence of right censoring. This model extends the proportional mean residual life model using an additive model as its covariate dependent baseline....... For the suggested model, some covariate effects are allowed to be time-varying. To estimate the model parameters, martingale estimating equations are developed, and the large sample properties of the resulting estimators are established. In addition, to assess the adequacy of the model, we investigate a goodness...... of fit test that is asymptotically justified. The proposed methodology is evaluated via simulation studies and further applied to a kidney cancer data set collected from a clinical trial....

  1. Comprehensive European dietary exposure model (CEDEM) for food additives.

    Science.gov (United States)

    Tennant, David R

    2016-05-01

    European methods for assessing dietary exposures to nutrients, additives and other substances in food are limited by the availability of detailed food consumption data for all member states. A proposed comprehensive European dietary exposure model (CEDEM) applies summary data published by the European Food Safety Authority (EFSA) in a deterministic model based on an algorithm from the EFSA intake method for food additives. The proposed approach can predict estimates of food additive exposure provided in previous EFSA scientific opinions that were based on the full European food consumption database.

  2. Additive Intensity Regression Models in Corporate Default Analysis

    DEFF Research Database (Denmark)

    Lando, David; Medhat, Mamdouh; Nielsen, Mads Stenbo

    2013-01-01

    We consider additive intensity (Aalen) models as an alternative to the multiplicative intensity (Cox) models for analyzing the default risk of a sample of rated, nonfinancial U.S. firms. The setting allows for estimating and testing the significance of time-varying effects. We use a variety of mo...

  3. [Urinary iodine excretion levels in schoolchildren from Quindío, 2006-2007].

    Science.gov (United States)

    Gallego, Martha L; Loango, Nelsy; Londoño, Angela L; Landazuri, Patricia

    2009-12-01

    Iodine nutritional status is measured by urinary iodine concentration thereby allowing risks involved in such deficiency or increase to be assessed. Studying the frequency of the risk of iodine deficiency disorders, or more than suitable iodine intake in schoolchildren from Quindío. Urinary iodine concentration was measured in a casual urine sample taken from each subject; this study lasted from 2006 to 2007. Median urinary iodine was 272.4 microg/L in the 444 samples analysed. 11.9% of schoolchildren had normal urinary iodine, 28.8% had iodine deficiency and 11.5% of them had a severe deficit, 12.6% moderate deficit and 4.7% slight deficit. 59.3% presented a risk of excessive iodine intake. The range of iodine deficiency in boys was 31% and 26.6% in girls (no significant difference). No significant difference was found with age; however, there was a significant difference between economic levels 1 and 2 (p iodine deficiency (median um iodine intake. The population being studied had severe iodine deficiencies (rural) and excessive intake (urban population), suggesting the absence or poor control of an iodization programme and additional exposure to factors causing iodine disorders. A programme is required for monitoring iodine disorders in the school population being studied.

  4. Iodine in diet

    Science.gov (United States)

    ... in a person's diet may cause goiter or hypothyroidism . Without enough iodine, the thyroid cells and the thyroid gland become enlarged. Deficiency happens more often in women than in men. It is also more common in pregnant women and older children. Getting enough iodine in ...

  5. Apoptosis imaging studies in various animal models using radio-iodinated peptide.

    Science.gov (United States)

    Kwak, Wonjung; Ha, Yeong Su; Soni, Nisarg; Lee, Woonghee; Park, Se-Il; Ahn, Heesu; An, Gwang Il; Kim, In-San; Lee, Byung-Heon; Yoo, Jeongsoo

    2015-01-01

    Apoptosis has a role in many medical disorders and treatments; hence, its non-invasive evaluation is one of the most riveting research topics. Currently annexin V is used as gold standard for imaging apoptosis. However, several drawbacks, including high background, slow body clearance, make it a suboptimum marker for apoptosis imaging. In this study, we radiolabeled the recently identified histone H1 targeting peptide (ApoPep-1) and evaluated its potential as a new apoptosis imaging agent in various animal models. ApoPep-1 (CQRPPR) was synthesized, and an extra tyrosine residue was added to its N-terminal end for radiolabeling. This peptide was radiolabeled with (124)I and (131)I and was tested for its serum stability. Surgery- and drug-induced apoptotic rat models were prepared for apoptosis evaluation, and PET imaging was performed. Doxorubicin was used for xenograft tumor treatment in mice, and the induced apoptosis was studied. Tumor metabolism and proliferation were assessed by [(18)F]FDG and [(18)F]FLT PET imaging and compared with ApoPep-1 after doxorubicin treatment. The peptide was radiolabeled at high purity, and it showed reasonably good stability in serum. Cell death was easily imaged by radiolabeled ApoPep-1 in an ischemia surgery model. And, liver apoptosis was more clearly identified by ApoPep-1 rather than [(124)I]annexin V in cycloheximide-treated models. Three doxorubicin doses inhibited tumor growth, which was evaluated by 30-40% decreases of [(18)F]FDG and [(18)F]FLT PET uptake in the tumor area. However, ApoPep-1 demonstrated more than 200% increase in tumor uptake after chemotherapy, while annexin V did not show any meaningful uptake in the tumor compared with the background. Biodistribution data were also in good agreement with the microPET imaging results. All of the experimental data clearly demonstrated high potential of the radiolabeled ApoPep-1 for in vivo apoptosis imaging.

  6. Iodine chemistry at severe accidents. A review and evaluation of the state-of-the-art in the field. APRI 5 report. Part I: Iodine chemistry at hypothetical severe accidents. A review of the state-of-the-art 2003. Part II: A comparison of our knowledge on iodine chemistry and fission products with the current models used in MAAP 4.0.5; Jodkemi under svaara haverier. En sammanstaellnig och vaerdering av kunskapslaeget inom omraadet. APRI 5 rapport. Del I: Jodkemi vid hypotetiska svaara haverier. En genomgaang av kunskapslaeget aar 2003. Del II: Jaemfoerelse av kunskapslaeget om jodkemi och fissionsprodukter med aktuella modeller i MAAP 4.0.5

    Energy Technology Data Exchange (ETDEWEB)

    Liljenzin, Jan-Olov [Liljenzins data och kemikonsult, Goeteborg (Sweden)

    2005-01-01

    The current report tries to summarize and analyze the state-of-the-art on Iodine chemistry relevant to the conditions expected during severe accidents in nuclear power plants. This has made it necessary to compare a considerable amount of data, new as well as old, in order to try to find the reasons behind some changes in the expected chemical behaviour of Iodine. In a few cases this has been far from simple. Many numerical values are given in this report. However, me numbers given should not be used in a non-critical way because they are often deduced from measurements whose interpretation depends on various kinds of systematic differences and assumptions with regard to technique, 'known' constants, and models applied. The most important observation today is that one can no longer uncritically assume that iodine is only released and transported as cesium iodide. The considerable effect that control rod material (including other construction materials) can have on the way in which an accident develops and on its iodine chemistry is clearly seen from the results of the experiments performed within the PHEBUS FP project. The second part of the report evaluates new knowledge on Iodine chemistry and Iodine behaviour of importance in severe nuclear reactor accidents. Also some new information regarding the behaviour and chemistry of other fission products has been collected. In the light of this information, the current modelling of Iodine behaviour in the MAAP code version 4.0.5 has been investigated. No modelling errors have been found. However, some of the equations used to calculate the vapour pressure of the components in the AlC-alloy used in PWR control rods give questionable results. An error in the MAAP manual was found which should be corrected. Finally, some suggestions are given for future improvements in the modelling of severe accidents used in MAAP for both BWRs and PWRs.

  7. Iodine mineral waters

    Directory of Open Access Journals (Sweden)

    Iluta Alexandru

    2011-11-01

    Full Text Available Iodine mineral waters are found especially in sub-Carpathian region, also in regions with Salif deposits. Waters are currently used iodine in drinking cure for chaps and Basedow. Are also indicated in balneology. Iodine water containing at least 1 mg L, there is pure iodine is usually given the nature of other types of mineral waters further: sodium chlorinated water (Bazna (50-70 mg iodine / l, Baile Govora (50 - 70 mg / l, Bălţăteşti (4-5 mg / l, salted Monteoru (30 mg / l, mine water mixed alkaline chlorination, sulphate, which are indicated for crenoterapie (hypo or isotonic to the bathrooms Olăneşti or Călimăneşti-Căciulata.

  8. Iodine generator for reclaimed water purification

    Science.gov (United States)

    Wynveen, R. A.; Powell, J. D.; Schubert, F. H. (Inventor)

    1977-01-01

    The system disclosed is for controlling the iodine level in a water supply in a spacecraft. It includes an iodine accumulator which stores crystalline iodine, an electrochemical valve to control the input of iodine to the drinking water and an iodine dispenser. A pump dispenses fluid through the iodine dispenser and an iodine sensor to a potable water tank storage. The iodine sensor electronically detects the iodine level in the water, and through electronic means, produces a correction current control. The correction current control operates the electro-chemical iodine valve to release iodine from the iodine accumulator into the iodine dispenser.

  9. Iodine Nutritional Status of School Children in Nauru 2015.

    Science.gov (United States)

    Huang, Chun-Jui; Tseng, Chi-Lung; Chen, Harn-Shen; Garabwan, Chanda; Korovo, Samuela; Tang, Kam-Tsun; Won, Justin Ging-Shing; Hsieh, Chang-Hsun; Wang, Fan-Fen

    2016-08-23

    Little is known about iodine nutritional status in island countries in the Pacific Ocean. The primary objective of this study was to report for the first time the iodine nutritional status of people in Nauru. In addition, sources of iodine nutrition (i.e., water and salt) were investigated. A school-based cross-sectional survey of children aged 6-12 years was conducted in three primary schools of Nauru. Urinary iodine concentration (UIC) was determined by spot urine samples. Available water and salt samples in Nauru were collected for the measurement of iodine content. A food frequency questionnaire was conducted. The median UIC was 142 μg/L, and 25.2% and 7.4% of the population had median UIC below 100 μg/L and 50 μg/L, respectively. Natural iodine-containing foods such as seaweeds and agar were rare. Iodine was undetectable in Nauruan tank water, filtered tap water, and raindrops. Of the analyzed salt products, five kinds were non-iodized, and three were iodized (iodine content: 15 ppm, 65 ppm, and 68 ppm, respectively). The results indicate that the iodine status in Nauruan school children is adequate. Iodized salt may serve as an important source of iodine nutrition in Nauru.

  10. Iodine Nutritional Status of School Children in Nauru 2015

    Directory of Open Access Journals (Sweden)

    Chun-Jui Huang

    2016-08-01

    Full Text Available Little is known about iodine nutritional status in island countries in the Pacific Ocean. The primary objective of this study was to report for the first time the iodine nutritional status of people in Nauru. In addition, sources of iodine nutrition (i.e., water and salt were investigated. A school-based cross-sectional survey of children aged 6–12 years was conducted in three primary schools of Nauru. Urinary iodine concentration (UIC was determined by spot urine samples. Available water and salt samples in Nauru were collected for the measurement of iodine content. A food frequency questionnaire was conducted. The median UIC was 142 μg/L, and 25.2% and 7.4% of the population had median UIC below 100 μg/L and 50 μg/L, respectively. Natural iodine-containing foods such as seaweeds and agar were rare. Iodine was undetectable in Nauruan tank water, filtered tap water, and raindrops. Of the analyzed salt products, five kinds were non-iodized, and three were iodized (iodine content: 15 ppm, 65 ppm, and 68 ppm, respectively. The results indicate that the iodine status in Nauruan school children is adequate. Iodized salt may serve as an important source of iodine nutrition in Nauru.

  11. Using Set Model for Learning Addition of Integers

    Directory of Open Access Journals (Sweden)

    Umi Puji Lestari

    2015-07-01

    Full Text Available This study aims to investigate how set model can help students' understanding of addition of integers in fourth grade. The study has been carried out to 23 students and a teacher of IVC SD Iba Palembang in January 2015. This study is a design research that also promotes PMRI as the underlying design context and activity. Results showed that the use of set models that is packaged in activity of recording of financial transactions in two color chips and card game can help students to understand the concept of zero pair, addition with the same colored chips, and cancellation strategy.

  12. Process chain modeling and selection in an additive manufacturing context

    DEFF Research Database (Denmark)

    Thompson, Mary Kathryn; Stolfi, Alessandro; Mischkot, Michael

    2016-01-01

    can compete with traditional process chains for small production runs. Combining both types of technology added cost but no benefit in this case. The new process chain model can be used to explain the results and support process selection, but process chain prototyping is still important for rapidly......This paper introduces a new two-dimensional approach to modeling manufacturing process chains. This approach is used to consider the role of additive manufacturing technologies in process chains for a part with micro scale features and no internal geometry. It is shown that additive manufacturing...

  13. Mathematical modeling of a photovoltaic-laser energy converter for iodine laser radiation

    Science.gov (United States)

    Walker, Gilbert H.; Heinbockel, John H.

    1987-01-01

    Space-based laser power systems will require converters to change laser radiation into electricity. Vertical junction photovoltaic converters are promising devices for this use. A promising laser for the laser power station is the t-C4F9I laser which emits radiation at a wavelength of 1.315 microns. This paper describes the results of mathematical modeling of a photovoltaic-laser energy converter for use with this laser. The material for this photovoltaic converter is Ga(53)In(47)As which has a bandgap energy of 0.94 eV, slightly below the energy of the laser photons (0.943 eV). Results of a study optimizing the converter parameters are presented. Calculated efficiency for a 1000 vertical junction converter is 42.5 percent at a power density of 1 x 10 to the 3d power w/sq cm.

  14. Electroacoustics modeling of piezoelectric welders for ultrasonic additive manufacturing processes

    Science.gov (United States)

    Hehr, Adam; Dapino, Marcelo J.

    2016-04-01

    Ultrasonic additive manufacturing (UAM) is a recent 3D metal printing technology which utilizes ultrasonic vibrations from high power piezoelectric transducers to additively weld similar and dissimilar metal foils. CNC machining is used intermittent of welding to create internal channels, embed temperature sensitive components, sensors, and materials, and for net shaping parts. Structural dynamics of the welder and work piece influence the performance of the welder and part quality. To understand the impact of structural dynamics on UAM, a linear time-invariant model is used to relate system shear force and electric current inputs to the system outputs of welder velocity and voltage. Frequency response measurements are combined with in-situ operating measurements of the welder to identify model parameters and to verify model assumptions. The proposed LTI model can enhance process consistency, performance, and guide the development of improved quality monitoring and control strategies.

  15. The Impact of Carrot Enriched in Iodine through Soil Fertilization on Iodine Concentration and Selected Biochemical Parameters in Wistar Rats.

    Science.gov (United States)

    Piątkowska, Ewa; Kopeć, Aneta; Bieżanowska-Kopeć, Renata; Pysz, Mirosław; Kapusta-Duch, Joanna; Koronowicz, Aneta Agnieszka; Smoleń, Sylwester; Skoczylas, Łukasz; Ledwożyw-Smoleń, Iwona; Rakoczy, Roksana; Maślak, Edyta

    2016-01-01

    Iodine is one of the trace elements which are essential for mammalian life. The major objective of iodine biofortification of plants is to obtain food rich in this trace element, which may increase its consumption by various populations. Additionally, it may reduce the risk of iodine deficiency diseases. In this research for the first time we have assessed the bioavailability of iodine from raw or cooked carrot biofortified with this trace element on iodine concentration in selected tissues and various biochemical parameters as well as mRNA expression of some genes involved in iodine metabolism in Wistar rats. Statistically, a significantly higher iodine level was determined in urine, faeces and selected tissues of rats fed a diet containing biofortified raw carrot as compared to a diet without iodine and a diet containing control cooked carrot. Biofortified raw carrot significantly increased triiodothyronine concentration as compared to animals from other experimental groups. The highest thyroid stimulating hormone level was determined in rats fed control cooked carrots. mRNA expression of selected genes was affected by different dietary treatment in rats' hearts. Biofortified raw and cooked carrot could be taken into account as a potential source of iodine in daily diets to prevent iodine deficiency in various populations.

  16. The Impact of Carrot Enriched in Iodine through Soil Fertilization on Iodine Concentration and Selected Biochemical Parameters in Wistar Rats.

    Directory of Open Access Journals (Sweden)

    Ewa Piątkowska

    Full Text Available Iodine is one of the trace elements which are essential for mammalian life. The major objective of iodine biofortification of plants is to obtain food rich in this trace element, which may increase its consumption by various populations. Additionally, it may reduce the risk of iodine deficiency diseases. In this research for the first time we have assessed the bioavailability of iodine from raw or cooked carrot biofortified with this trace element on iodine concentration in selected tissues and various biochemical parameters as well as mRNA expression of some genes involved in iodine metabolism in Wistar rats. Statistically, a significantly higher iodine level was determined in urine, faeces and selected tissues of rats fed a diet containing biofortified raw carrot as compared to a diet without iodine and a diet containing control cooked carrot. Biofortified raw carrot significantly increased triiodothyronine concentration as compared to animals from other experimental groups. The highest thyroid stimulating hormone level was determined in rats fed control cooked carrots. mRNA expression of selected genes was affected by different dietary treatment in rats' hearts. Biofortified raw and cooked carrot could be taken into account as a potential source of iodine in daily diets to prevent iodine deficiency in various populations.

  17. Is placental iodine content related to dietary iodine intake?

    LENUS (Irish Health Repository)

    Burns, R

    2011-08-01

    Delivery of iodine to the foetus depends not only on maternal dietary iodine intake but also on the presence of a functioning placental transport system. A role for the placenta as an iodine storage organ has been suggested, and this study compares the iodine content of placentas from women giving birth at term in Ireland and Iran, areas with median urinary iodine of 79 and 206 μg\\/l respectively.

  18. Ultrahigh iodine adsorption in porous organic frameworks

    KAUST Repository

    Pei, Cuiying

    2014-01-01

    We present two porous organic frameworks (POFs), PAF-1 and JUC-Z2, with ultrahigh iodine capture capacity. The iodine vapor uptake of PAF-1 and JUC-Z2 were 1.86 g g-1 and 1.44 g g-1 respectively at 298 K per 40 Pa, which is extremely high for such low pressure sorption conditions. In addition, PAF-1 and JUC-Z2 could adsorb iodine over water with the selectivity of 5.1 and 6.5 respectively. The isosteric enthalpy at zero surface coverage, calculated by a virial equation with the iodine vapor sorption isotherms at 298 K and 313 K of JUC-Z2, reached -51.1 kJ mol-1, which was much higher than the coverage of PAF-1 (-14.9 kJ mol-1). Raman measurement confirmed the polyiodide to be I5 - in POFs. Furthermore, solvents with different polarities, such as n-hexane, chloroform, and methanol, were chosen to conduct iodine binding measurements on PAF-1 and JUC-Z2. The formation constant Kf for POFs in n-hexane, chloroform and methanol drastically decreased with the increase in polarity, thus illustrating the important role of solvents in iodine binding. © the Partner Organisations 2014.

  19. International standard problem (ISP) no. 41 follow up exercise: Containment iodine computer code exercise: parametric studies

    Energy Technology Data Exchange (ETDEWEB)

    Ball, J.; Glowa, G.; Wren, J. [Atomic Energy of Canada Limited, Chalk River, Ontario (Canada); Ewig, F. [GRS Koln (Germany); Dickenson, S. [AEAT, (United Kingdom); Billarand, Y.; Cantrel, L. [IPSN (France); Rydl, A. [NRIR (Czech Republic); Royen, J. [OECD/NEA (France)

    2001-11-01

    This report describes the results of the second phase of International Standard Problem (ISP) 41, an iodine behaviour code comparison exercise. The first phase of the study, which was based on a simple Radioiodine Test Facility (RTF) experiment, demonstrated that all of the iodine behaviour codes had the capability to reproduce iodine behaviour for a narrow range of conditions (single temperature, no organic impurities, controlled pH steps). The current phase, a parametric study, was designed to evaluate the sensitivity of iodine behaviour codes to boundary conditions such as pH, dose rate, temperature and initial I{sup -} concentration. The codes used in this exercise were IODE(IPSN), IODE(NRIR), IMPAIR(GRS), INSPECT(AEAT), IMOD(AECL) and LIRIC(AECL). The parametric study described in this report identified several areas of discrepancy between the various codes. In general, the codes agree regarding qualitative trends, but their predictions regarding the actual amount of volatile iodine varied considerably. The largest source of the discrepancies between code predictions appears to be their different approaches to modelling the formation and destruction of organic iodides. A recommendation arising from this exercise is that an additional code comparison exercise be performed on organic iodide formation, against data obtained front intermediate-scale studies (two RTF (AECL, Canada) and two CAIMAN facility, (IPSN, France) experiments have been chosen). This comparison will allow each of the code users to realistically evaluate and improve the organic iodide behaviour sub-models within their codes. (author)

  20. Single-Index Additive Vector Autoregressive Time Series Models

    KAUST Repository

    LI, YEHUA

    2009-09-01

    We study a new class of nonlinear autoregressive models for vector time series, where the current vector depends on single-indexes defined on the past lags and the effects of different lags have an additive form. A sufficient condition is provided for stationarity of such models. We also study estimation of the proposed model using P-splines, hypothesis testing, asymptotics, selection of the order of the autoregression and of the smoothing parameters and nonlinear forecasting. We perform simulation experiments to evaluate our model in various settings. We illustrate our methodology on a climate data set and show that our model provides more accurate yearly forecasts of the El Niño phenomenon, the unusual warming of water in the Pacific Ocean. © 2009 Board of the Foundation of the Scandinavian Journal of Statistics.

  1. Validation of transport models using additive flux minimization technique

    Energy Technology Data Exchange (ETDEWEB)

    Pankin, A. Y.; Kruger, S. E. [Tech-X Corporation, 5621 Arapahoe Ave., Boulder, Colorado 80303 (United States); Groebner, R. J. [General Atomics, San Diego, California 92121 (United States); Hakim, A. [Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543-0451 (United States); Kritz, A. H.; Rafiq, T. [Department of Physics, Lehigh University, Bethlehem, Pennsylvania 18015 (United States)

    2013-10-15

    A new additive flux minimization technique is proposed for carrying out the verification and validation (V and V) of anomalous transport models. In this approach, the plasma profiles are computed in time dependent predictive simulations in which an additional effective diffusivity is varied. The goal is to obtain an optimal match between the computed and experimental profile. This new technique has several advantages over traditional V and V methods for transport models in tokamaks and takes advantage of uncertainty quantification methods developed by the applied math community. As a demonstration of its efficiency, the technique is applied to the hypothesis that the paleoclassical density transport dominates in the plasma edge region in DIII-D tokamak discharges. A simplified version of the paleoclassical model that utilizes the Spitzer resistivity for the parallel neoclassical resistivity and neglects the trapped particle effects is tested in this paper. It is shown that a contribution to density transport, in addition to the paleoclassical density transport, is needed in order to describe the experimental profiles. It is found that more additional diffusivity is needed at the top of the H-mode pedestal, and almost no additional diffusivity is needed at the pedestal bottom. The implementation of this V and V technique uses the FACETS::Core transport solver and the DAKOTA toolkit for design optimization and uncertainty quantification. The FACETS::Core solver is used for advancing the plasma density profiles. The DAKOTA toolkit is used for the optimization of plasma profiles and the computation of the additional diffusivity that is required for the predicted density profile to match the experimental profile.

  2. Just Another Gibbs Additive Modeler: Interfacing JAGS and mgcv

    Directory of Open Access Journals (Sweden)

    Simon N. Wood

    2016-12-01

    Full Text Available The BUGS language offers a very flexible way of specifying complex statistical models for the purposes of Gibbs sampling, while its JAGS variant offers very convenient R integration via the rjags package. However, including smoothers in JAGS models can involve some quite tedious coding, especially for multivariate or adaptive smoothers. Further, if an additive smooth structure is required then some care is needed, in order to centre smooths appropriately, and to find appropriate starting values. R package mgcv implements a wide range of smoothers, all in a manner appropriate for inclusion in JAGS code, and automates centring and other smooth setup tasks. The purpose of this note is to describe an interface between mgcv and JAGS, based around an R function, jagam, which takes a generalized additive model (GAM as specified in mgcv and automatically generates the JAGS model code and data required for inference about the model via Gibbs sampling. Although the auto-generated JAGS code can be run as is, the expectation is that the user would wish to modify it in order to add complex stochastic model components readily specified in JAGS. A simple interface is also provided for visualisation and further inference about the estimated smooth components using standard mgcv functionality. The methods described here will be un-necessarily inefficient if all that is required is fully Bayesian inference about a standard GAM, rather than the full flexibility of JAGS. In that case the BayesX package would be more efficient.

  3. Modeling the influence of limestone addition on cement hydration

    Directory of Open Access Journals (Sweden)

    Ashraf Ragab Mohamed

    2015-03-01

    Full Text Available This paper addresses the influence of using Portland limestone cement “PLC” on cement hydration by characterization of its microstructure development. The European Standard EN 197-1:2011 and Egyptian specification ESS 4756-1/2009 permit the cement to contain up to 20% ground limestone. The computational tools assist in better understanding the influence of limestone additions on cement hydration and microstructure development to facilitate the acceptance of these more economical and ecological materials. μic model has been developed to enable the modeling of microstructural evolution of cementitious materials. In this research μic model is used to simulate both the influence of limestone as fine filler, providing additional surfaces for the nucleation and growth of hydration products. Limestone powder also reacts relatively slow with hydrating cement to form monocarboaluminate (AFmc phase, similar to the mono-sulfoaluminate (AFm phase formed in ordinary Portland cement. The model results reveal that limestone cement has accelerated cement hydration rate, previous experimental results and computer model “cemhyd3d” are used to validate this model.

  4. Direct evidence for coastal iodine particles from Laminaria macroalgae – linkage to emissions of molecular iodine

    Directory of Open Access Journals (Sweden)

    D. Wevill

    2004-02-01

    Full Text Available Renewal of ultrafine aerosols in the marine boundary layer may lead to repopulation of the marine distribution and ultimately determine the concentration of cloud condensation nuclei (CCN. Thus the formation of nanometre-scale particles can lead to enhanced scattering of incoming radiation and a net cooling of the atmosphere. The recent demonstration of the chamber formation of new particles from the photolytic production of condensable iodine-containing compounds from diiodomethane (CH2I2, (O'Dowd et al., 2002; Kolb, 2002; Jimenez et al., 2003a; Burkholder and Ravishankara, 2003, provides an additional mechanism to the gas-to-particle conversion of sulphuric acid formed in the photo-oxidation of dimethylsulphide for marine aerosol repopulation. CH2I2 is emitted from seaweeds (Carpenter et al., 1999, 2000 and has been suggested as an initiator of particle formation. We demonstrate here for the first time that ultrafine iodine-containing particles are produced by intertidal macroalgae exposed to ambient levels of ozone. The particle composition is very similar both to those formed in the chamber photo-oxidation of diiodomethane and in the oxidation of molecular iodine by ozone. The particles formed in all three systems are similarly aspherical and behave alike when exposed to increased humidity environments. Direct coastal boundary layer observations of molecular iodine, ultrafine particle production and iodocarbons are reported. Using a newly measured molecular iodine photolysis rate, it is shown that, if atomic iodine is involved in the observed particle bursts, it is of the order of at least 1000 times more likely to result from molecular iodine photolysis than diiodomethane photolysis. A hypothesis for molecular iodine release from intertidal macroalgae is presented and the potential importance of macroalgal iodine particles in their contribution to CCN and global radiative forcing are discussed.

  5. Predicting the Probability of Lightning Occurrence with Generalized Additive Models

    Science.gov (United States)

    Fabsic, Peter; Mayr, Georg; Simon, Thorsten; Zeileis, Achim

    2017-04-01

    This study investigates the predictability of lightning in complex terrain. The main objective is to estimate the probability of lightning occurrence in the Alpine region during summertime afternoons (12-18 UTC) at a spatial resolution of 64 × 64 km2. Lightning observations are obtained from the ALDIS lightning detection network. The probability of lightning occurrence is estimated using generalized additive models (GAM). GAMs provide a flexible modelling framework to estimate the relationship between covariates and the observations. The covariates, besides spatial and temporal effects, include numerous meteorological fields from the ECMWF ensemble system. The optimal model is chosen based on a forward selection procedure with out-of-sample mean squared error as a performance criterion. Our investigation shows that convective precipitation and mid-layer stability are the most influential meteorological predictors. Both exhibit intuitive, non-linear trends: higher values of convective precipitation indicate higher probability of lightning, and large values of the mid-layer stability measure imply low lightning potential. The performance of the model was evaluated against a climatology model containing both spatial and temporal effects. Taking the climatology model as a reference forecast, our model attains a Brier Skill Score of approximately 46%. The model's performance can be further enhanced by incorporating the information about lightning activity from the previous time step, which yields a Brier Skill Score of 48%. These scores show that the method is able to extract valuable information from the ensemble to produce reliable spatial forecasts of the lightning potential in the Alps.

  6. Genomic breeding value estimation using nonparametric additive regression models

    Directory of Open Access Journals (Sweden)

    Solberg Trygve

    2009-01-01

    Full Text Available Abstract Genomic selection refers to the use of genomewide dense markers for breeding value estimation and subsequently for selection. The main challenge of genomic breeding value estimation is the estimation of many effects from a limited number of observations. Bayesian methods have been proposed to successfully cope with these challenges. As an alternative class of models, non- and semiparametric models were recently introduced. The present study investigated the ability of nonparametric additive regression models to predict genomic breeding values. The genotypes were modelled for each marker or pair of flanking markers (i.e. the predictors separately. The nonparametric functions for the predictors were estimated simultaneously using additive model theory, applying a binomial kernel. The optimal degree of smoothing was determined by bootstrapping. A mutation-drift-balance simulation was carried out. The breeding values of the last generation (genotyped was predicted using data from the next last generation (genotyped and phenotyped. The results show moderate to high accuracies of the predicted breeding values. A determination of predictor specific degree of smoothing increased the accuracy.

  7. High-dimensional additive hazard models and the Lasso

    CERN Document Server

    Gaïffas, Séphane

    2011-01-01

    We consider a general high-dimensional additive hazard model in a non-asymptotic setting, including regression for censored-data. In this context, we consider a Lasso estimator with a fully data-driven $\\ell_1$ penalization, which is tuned for the estimation problem at hand. We prove sharp oracle inequalities for this estimator. Our analysis involves a new "data-driven" Bernstein's inequality, that is of independent interest, where the predictable variation is replaced by the optional variation.

  8. Iodine Hall Thruster

    Science.gov (United States)

    Szabo, James

    2015-01-01

    Iodine enables dramatic mass and cost savings for lunar and Mars cargo missions, including Earth escape and near-Earth space maneuvers. The demonstrated throttling ability of iodine is important for a singular thruster that might be called upon to propel a spacecraft from Earth to Mars or Venus. The ability to throttle efficiently is even more important for missions beyond Mars. In the Phase I project, Busek Company, Inc., tested an existing Hall thruster, the BHT-8000, on iodine propellant. The thruster was fed by a high-flow iodine feed system and supported by an existing Busek hollow cathode flowing xenon gas. The Phase I propellant feed system was evolved from a previously demonstrated laboratory feed system. Throttling of the thruster between 2 and 11 kW at 200 to 600 V was demonstrated. Testing showed that the efficiency of iodine fueled BHT-8000 is the same as with xenon, with iodine delivering a slightly higher thrust-to-power (T/P) ratio. In Phase II, a complete iodine-fueled system was developed, including the thruster, hollow cathode, and iodine propellant feed system. The nominal power of the Phase II system is 8 kW; however, it can be deeply throttled as well as clustered to much higher power levels. The technology also can be scaled to greater than 100 kW per thruster to support megawatt-class missions. The target thruster efficiency for the full-scale system is 65 percent at high specific impulse (Isp) (approximately 3,000 s) and 60 percent at high thrust (Isp approximately 2,000 s).

  9. Semiparametric Additive Transformation Model under Current Status Data

    CERN Document Server

    Cheng, Guang

    2011-01-01

    We consider the efficient estimation of the semiparametric additive transformation model with current status data. A wide range of survival models and econometric models can be incorporated into this general transformation framework. We apply the B-spline approach to simultaneously estimate the linear regression vector, the nondecreasing transformation function, and a set of nonparametric regression functions. We show that the parametric estimate is semiparametric efficient in the presence of multiple nonparametric nuisance functions. An explicit consistent B-spline estimate of the asymptotic variance is also provided. All nonparametric estimates are smooth, and shown to be uniformly consistent and have faster than cubic rate of convergence. Interestingly, we observe the convergence rate interfere phenomenon, i.e., the convergence rates of B-spline estimators are all slowed down to equal the slowest one. The constrained optimization is not required in our implementation. Numerical results are used to illustra...

  10. Thermal modelling of extrusion based additive manufacturing of composite materials

    DEFF Research Database (Denmark)

    Jensen, Mathias Laustsen; Sonne, Mads Rostgaard; Hattel, Jesper Henri

    2017-01-01

    One of the hottest topics regarding manufacturing these years is additive manufacturing (AM). AM is a young branch of manufacturing techniques, which by nature is disruptive due to its completely different manufacturing approach, wherein material is added instead of removed. By adding material...... process knowledge, and validating the generated toolpaths before the real manufacturing process takes place: Hence removing time consuming and expensive trial-and-error processes for new products. This study applies a 2D restricted finite volume model aimed to describe thermoplastic Acrylonitrille......-butadiene-styrene (ABS) and thermosetting polyurethane (PU) material extrusion processes. During the experimental evaluation of the produced models it is found that some critical material properties needs to be further investigated to increase the precision of the model. It is however also found that even with only...

  11. Multiscale and Multiphysics Modeling of Additive Manufacturing of Advanced Materials

    Science.gov (United States)

    Liou, Frank; Newkirk, Joseph; Fan, Zhiqiang; Sparks, Todd; Chen, Xueyang; Fletcher, Kenneth; Zhang, Jingwei; Zhang, Yunlu; Kumar, Kannan Suresh; Karnati, Sreekar

    2015-01-01

    The objective of this proposed project is to research and develop a prediction tool for advanced additive manufacturing (AAM) processes for advanced materials and develop experimental methods to provide fundamental properties and establish validation data. Aircraft structures and engines demand materials that are stronger, useable at much higher temperatures, provide less acoustic transmission, and enable more aeroelastic tailoring than those currently used. Significant improvements in properties can only be achieved by processing the materials under nonequilibrium conditions, such as AAM processes. AAM processes encompass a class of processes that use a focused heat source to create a melt pool on a substrate. Examples include Electron Beam Freeform Fabrication and Direct Metal Deposition. These types of additive processes enable fabrication of parts directly from CAD drawings. To achieve the desired material properties and geometries of the final structure, assessing the impact of process parameters and predicting optimized conditions with numerical modeling as an effective prediction tool is necessary. The targets for the processing are multiple and at different spatial scales, and the physical phenomena associated occur in multiphysics and multiscale. In this project, the research work has been developed to model AAM processes in a multiscale and multiphysics approach. A macroscale model was developed to investigate the residual stresses and distortion in AAM processes. A sequentially coupled, thermomechanical, finite element model was developed and validated experimentally. The results showed the temperature distribution, residual stress, and deformation within the formed deposits and substrates. A mesoscale model was developed to include heat transfer, phase change with mushy zone, incompressible free surface flow, solute redistribution, and surface tension. Because of excessive computing time needed, a parallel computing approach was also tested. In addition

  12. Testing exclusion restrictions and additive separability in sample selection models

    DEFF Research Database (Denmark)

    Huber, Martin; Mellace, Giovanni

    2014-01-01

    Standard sample selection models with non-randomly censored outcomes assume (i) an exclusion restriction (i.e., a variable affecting selection, but not the outcome) and (ii) additive separability of the errors in the selection process. This paper proposes tests for the joint satisfaction of these......Standard sample selection models with non-randomly censored outcomes assume (i) an exclusion restriction (i.e., a variable affecting selection, but not the outcome) and (ii) additive separability of the errors in the selection process. This paper proposes tests for the joint satisfaction...... of these assumptions by applying the approach of Huber and Mellace (Testing instrument validity for LATE identification based on inequality moment constraints, 2011) (for testing instrument validity under treatment endogeneity) to the sample selection framework. We show that the exclusion restriction and additive...... separability imply two testable inequality constraints that come from both point identifying and bounding the outcome distribution of the subpopulation that is always selected/observed. We apply the tests to two variables for which the exclusion restriction is frequently invoked in female wage regressions: non...

  13. Two-stage local M-estimation of additive models

    Institute of Scientific and Technical Information of China (English)

    JIANG JianCheng; LI JianTao

    2008-01-01

    This paper studies local M-estimation of the nonparametric components of additive models. A two-stage local M-estimation procedure is proposed for estimating the additive components and their derivatives. Under very mild conditions, the proposed estimators of each additive component and its derivative are jointly asymptotically normal and share the same asymptotic distributions as they would be if the other components were known. The established asymptotic results also hold for two particular local M-estimations: the local least squares and least absolute deviation estimations. However,for general two-stage local M-estimation with continuous and nonlinear ψ-functions, its implementation is time-consuming. To reduce the computational burden, one-step approximations to the two-stage local M-estimators are developed. The one-step estimators are shown to achieve the same efficiency as the fully iterative two-stage local M-estimators, which makes the two-stage local M-estimation more feasible in practice. The proposed estimators inherit the advantages and at the same time overcome the disadvantages of the local least-squares based smoothers. In addition, the practical implementation of the proposed estimation is considered in details. Simulations demonstrate the merits of the two-stage local M-estimation, and a real example illustrates the performance of the methodology.

  14. Two-stage local M-estimation of additive models

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    This paper studies local M-estimation of the nonparametric components of additive models.A two-stage local M-estimation procedure is proposed for estimating the additive components and their derivatives.Under very mild conditions,the proposed estimators of each additive component and its derivative are jointly asymptotically normal and share the same asymptotic distributions as they would be if the other components were known.The established asymptotic results also hold for two particular local M-estimations:the local least squares and least absolute deviation estimations.However,for general two-stage local M-estimation with continuous and nonlinear ψ-functions,its implementation is time-consuming.To reduce the computational burden,one-step approximations to the two-stage local M-estimators are developed.The one-step estimators are shown to achieve the same effciency as the fully iterative two-stage local M-estimators,which makes the two-stage local M-estimation more feasible in practice.The proposed estimators inherit the advantages and at the same time overcome the disadvantages of the local least-squares based smoothers.In addition,the practical implementation of the proposed estimation is considered in details.Simulations demonstrate the merits of the two-stage local M-estimation,and a real example illustrates the performance of the methodology.

  15. Methods to assess iron and iodine status

    NARCIS (Netherlands)

    Zimmermann, M.B.

    2008-01-01

    Four methods are recommended for assessment of iodine nutrition: urinary iodine concentration, the goitre rate, and blood concentrations of thyroid stimulating hormone and thyroglobulin. These indicators are complementary, in that urinary iodine is a sensitive indicator of recent iodine intake

  16. Serum and tissue iodine concentrations in rats fed diets supplemented with kombu powder or potassium iodide.

    Science.gov (United States)

    Yoshida, Munehiro; Mukama, Ayumi; Hosomi, Ryota; Fukunaga, Kenji; Nishiyama, Toshimasa

    2014-01-01

    Serum and tissue iodine concentration was measured in rats fed a diet supplemented with powdered kombu (Saccharina sculpera) or potassium iodide to evaluate the absorption of iodine from kombu. Eighteen male 5-wk-old Wistar rats were divided into three groups and fed a basal AIN93G diet (iodine content, 0.2 mg/kg) or the basal diet supplemented with iodine (183 mg/kg) either in the form of kombu powder or potassium iodine (KI) for 4 wk. There were no differences in weight gain or serum biochemistry tests (alanine aminotransferase and aspartate aminotransferase activity, and total serum cholesterol and triglyceride concentration) after iodine supplementation. In addition, serum levels of the thyroid hormones thyroxine and triiodothyronine, as well as thyroid-stimulating hormone, were not affected. On the other hand, serum and tissue (thyroid, liver and kidney) iodine concentrations were markedly elevated after iodine supplementation. There was no difference in thyroid iodine concentration between KI and kombu supplementation. However, there was a significant difference observed in the iodine concentrations of serum, liver and kidney between the two iodine sources; rats fed KI had iodine concentrations in these tissues 1.8 to 1.9 times higher than those in rats fed kombu powder. These results suggest that the absorption of iodine from kombu is reduced compared to that from potassium iodide.

  17. Sensitivity analysis of geometric errors in additive manufacturing medical models.

    Science.gov (United States)

    Pinto, Jose Miguel; Arrieta, Cristobal; Andia, Marcelo E; Uribe, Sergio; Ramos-Grez, Jorge; Vargas, Alex; Irarrazaval, Pablo; Tejos, Cristian

    2015-03-01

    Additive manufacturing (AM) models are used in medical applications for surgical planning, prosthesis design and teaching. For these applications, the accuracy of the AM models is essential. Unfortunately, this accuracy is compromised due to errors introduced by each of the building steps: image acquisition, segmentation, triangulation, printing and infiltration. However, the contribution of each step to the final error remains unclear. We performed a sensitivity analysis comparing errors obtained from a reference with those obtained modifying parameters of each building step. Our analysis considered global indexes to evaluate the overall error, and local indexes to show how this error is distributed along the surface of the AM models. Our results show that the standard building process tends to overestimate the AM models, i.e. models are larger than the original structures. They also show that the triangulation resolution and the segmentation threshold are critical factors, and that the errors are concentrated at regions with high curvatures. Errors could be reduced choosing better triangulation and printing resolutions, but there is an important need for modifying some of the standard building processes, particularly the segmentation algorithms. Copyright © 2015 IPEM. Published by Elsevier Ltd. All rights reserved.

  18. Iodine nutrition in pregnancy and lactation.

    Science.gov (United States)

    Leung, Angela M; Pearce, Elizabeth N; Braverman, Lewis E

    2011-12-01

    Adequate iodine intake is required for the synthesis of thyroid hormones that are important for normal fetal and infant neurodevelopment. In this review, we discuss iodine physiology during pregnancy and lactation, methods to assess iodine sufficiency, the importance of adequate iodine nutrition, studies of iodine supplementation during pregnancy and lactation, the consequences of hypothyroidism during pregnancy, the current status of iodine nutrition in the United States, the global efforts toward achieving universal iodine sufficiency, and substances that may interfere with iodine use.

  19. Estimation and variable selection for generalized additive partial linear models

    KAUST Repository

    Wang, Li

    2011-08-01

    We study generalized additive partial linear models, proposing the use of polynomial spline smoothing for estimation of nonparametric functions, and deriving quasi-likelihood based estimators for the linear parameters. We establish asymptotic normality for the estimators of the parametric components. The procedure avoids solving large systems of equations as in kernel-based procedures and thus results in gains in computational simplicity. We further develop a class of variable selection procedures for the linear parameters by employing a nonconcave penalized quasi-likelihood, which is shown to have an asymptotic oracle property. Monte Carlo simulations and an empirical example are presented for illustration. © Institute of Mathematical Statistics, 2011.

  20. Additive Manufacturing of Medical Models--Applications in Rhinology.

    Science.gov (United States)

    Raos, Pero; Klapan, Ivica; Galeta, Tomislav

    2015-09-01

    In the paper we are introducing guidelines and suggestions for use of 3D image processing SW in head pathology diagnostic and procedures for obtaining physical medical model by additive manufacturing/rapid prototyping techniques, bearing in mind the improvement of surgery performance, its maximum security and faster postoperative recovery of patients. This approach has been verified in two case reports. In the treatment we used intelligent classifier-schemes for abnormal patterns using computer-based system for 3D-virtual and endoscopic assistance in rhinology, with appropriate visualization of anatomy and pathology within the nose, paranasal sinuses, and scull base area.

  1. Malliavin's calculus in insider models: Additional utility and free lunches

    OpenAIRE

    2002-01-01

    We consider simple models of financial markets with regular traders and insiders possessing some extra information hidden in a random variable which is accessible to the regular trader only at the end of the trading interval. The problems we focus on are the calculation of the additional utility of the insider and a study of his free lunch possibilities. The information drift, i.e. the drift to eliminate in order to preserve the martingale property in the insider's filtration, turns out to be...

  2. Iodine deficiency in Europe.

    Science.gov (United States)

    Delange, F

    1995-01-18

    Iodine is a trace element present in the human body in minute amounts (15-20 mg in adults, i.e. 0.0285 x 10(-3)% of body weight). The only confirmed function of iodine is to constitute an essential substrate for the synthesis of thyroid hormones, tetraiodothyronine, thyroxine or T4 and triiodothyronine, T3 (1). In thyroxine, iodine is 60% by weight. Thyroid hormones, in turn, play a decisive role in the metabolism of all cells of the organism (2) and in the process of early growth and development of most organs, especially of the brain (3). Brain development in humans occurs from fetal life up to the third postnatal year (4). Consequently, a deficit in iodine and/or in thyroid hormones occurring during this critical period of life will result not only in the slowing down of the metabolic activities of all the cells of the organism but also in irreversible alterations in the development of the brain. The clinical consequence will be mental retardation (5). When the physiological requirements of iodine are not met in a given population, a series of functional and developmental abnormalities occur (Table 1), including thyroid function abnormalities and, when iodine deficiency is severe, endemic goiter and cretinism, endemic mental retardation, decreased fertility rate, increased perinatal death, and infant mortality. These complications, which constitute an hindrance to the development of the affected population, are grouped under the general heading of Iodine Deficiency Disorders, IDD (6). Broad geographic areas exist in which the population is affected by IDD.(ABSTRACT TRUNCATED AT 250 WORDS)

  3. Cost models of additive manufacturing: A literature review

    Directory of Open Access Journals (Sweden)

    G. Costabile

    2016-11-01

    Full Text Available From the past decades, increasing attention has been paid to the quality level of technological and mechanical properties achieved by the Additive Manufacturing (AM; these two elements have achieved a good performance, and it is possible to compare this with the results achieved by traditional technology. Therefore, the AM maturity is high enough to let industries adopt this technology in a more general production framework as the mechanical manufacturing industrial one is. Since the technological and mechanical properties are also beneficial for the materials produced with AM, the primary objective of this paper is to focus more on managerial facets, such as the cost control of a production environment, where these new technologies are present. This paper aims to analyse the existing literature about the cost models developed specifically for AM from an operations management point of view and discusses the strengths and weaknesses of all models.

  4. Multiscale Modeling of Powder Bed-Based Additive Manufacturing

    Science.gov (United States)

    Markl, Matthias; Körner, Carolin

    2016-07-01

    Powder bed fusion processes are additive manufacturing technologies that are expected to induce the third industrial revolution. Components are built up layer by layer in a powder bed by selectively melting confined areas, according to sliced 3D model data. This technique allows for manufacturing of highly complex geometries hardly machinable with conventional technologies. However, the underlying physical phenomena are sparsely understood and difficult to observe during processing. Therefore, an intensive and expensive trial-and-error principle is applied to produce components with the desired dimensional accuracy, material characteristics, and mechanical properties. This review presents numerical modeling approaches on multiple length scales and timescales to describe different aspects of powder bed fusion processes. In combination with tailored experiments, the numerical results enlarge the process understanding of the underlying physical mechanisms and support the development of suitable process strategies and component topologies.

  5. Kinetics approach to modeling of polymer additive degradation in lubricants

    Institute of Scientific and Technical Information of China (English)

    llyaI.KUDISH; RubenG.AIRAPETYAN; Michael; J.; COVITCH

    2001-01-01

    A kinetics problem for a degrading polymer additive dissolved in a base stock is studied.The polymer degradation may be caused by the combination of such lubricant flow parameters aspressure, elongational strain rate, and temperature as well as lubricant viscosity and the polymercharacteristics (dissociation energy, bead radius, bond length, etc.). A fundamental approach tothe problem of modeling mechanically induced polymer degradation is proposed. The polymerdegradation is modeled on the basis of a kinetic equation for the density of the statistical distribu-tion of polymer molecules as a function of their molecular weight. The integrodifferential kineticequation for polymer degradation is solved numerically. The effects of pressure, elongational strainrate, temperature, and lubricant viscosity on the process of lubricant degradation are considered.The increase of pressure promotes fast degradation while the increase of temperature delaysdegradation. A comparison of a numerically calculated molecular weight distribution with an ex-perimental one obtained in bench tests showed that they are in excellent agreement with eachother.

  6. Model Checking Vector Addition Systems with one zero-test

    CERN Document Server

    Bonet, Rémi; Leroux, Jérôme; Zeitoun, Marc

    2012-01-01

    We design a variation of the Karp-Miller algorithm to compute, in a forward manner, a finite representation of the cover (i.e., the downward closure of the reachability set) of a vector addition system with one zero-test. This algorithm yields decision procedures for several problems for these systems, open until now, such as place-boundedness or LTL model-checking. The proof techniques to handle the zero-test are based on two new notions of cover: the refined and the filtered cover. The refined cover is a hybrid between the reachability set and the classical cover. It inherits properties of the reachability set: equality of two refined covers is undecidable, even for usual Vector Addition Systems (with no zero-test), but the refined cover of a Vector Addition System is a recursive set. The second notion of cover, called the filtered cover, is the central tool of our algorithms. It inherits properties of the classical cover, and in particular, one can effectively compute a finite representation of this set, e...

  7. WATEQ3 geochemical model: thermodynamic data for several additional solids

    Energy Technology Data Exchange (ETDEWEB)

    Krupka, K.M.; Jenne, E.A.

    1982-09-01

    Geochemical models such as WATEQ3 can be used to model the concentrations of water-soluble pollutants that may result from the disposal of nuclear waste and retorted oil shale. However, for a model to competently deal with these water-soluble pollutants, an adequate thermodynamic data base must be provided that includes elements identified as important in modeling these pollutants. To this end, several minerals and related solid phases were identified that were absent from the thermodynamic data base of WATEQ3. In this study, the thermodynamic data for the identified solids were compiled and selected from several published tabulations of thermodynamic data. For these solids, an accepted Gibbs free energy of formation, ..delta..G/sup 0//sub f,298/, was selected for each solid phase based on the recentness of the tabulated data and on considerations of internal consistency with respect to both the published tabulations and the existing data in WATEQ3. For those solids not included in these published tabulations, Gibbs free energies of formation were calculated from published solubility data (e.g., lepidocrocite), or were estimated (e.g., nontronite) using a free-energy summation method described by Mattigod and Sposito (1978). The accepted or estimated free energies were then combined with internally consistent, ancillary thermodynamic data to calculate equilibrium constants for the hydrolysis reactions of these minerals and related solid phases. Including these values in the WATEQ3 data base increased the competency of this geochemical model in applications associated with the disposal of nuclear waste and retorted oil shale. Additional minerals and related solid phases that need to be added to the solubility submodel will be identified as modeling applications continue in these two programs.

  8. Consequences of iodine deficiency and excess in pregnant women: an overview of current knowns and unknowns12

    Science.gov (United States)

    Lazarus, John H; Moreno-Reyes, Rodrigo; Zimmermann, Michael B

    2016-01-01

    Severe iodine deficiency during development results in maternal and fetal hypothyroidism and associated serious adverse health effects, including cretinism and growth retardation. Universal salt iodization is the first-line strategy for the elimination of severe iodine deficiency. Iodine supplementation is recommended for vulnerable groups in severely iodine-deficient regions where salt iodization is infeasible or insufficient. A recent clinical trial has informed best practices for iodine supplementation of severely iodine-deficient lactating mothers. Because of successful programs of universal salt iodization in formerly severely iodine-deficient regions around the world, public health concern has shifted toward mild to moderate iodine deficiency, which remains prevalent in many regions, especially among pregnant women. Observational studies have shown associations between both mild maternal iodine deficiency and mild maternal thyroid hypofunction and decreased child cognition. Iodine supplementation has been shown to improve indexes of maternal thyroid function, even in marginally iodine-deficient areas. However, no data are yet available from randomized controlled trials in regions of mild to moderate iodine insufficiency on the relation between maternal iodine supplementation and neurobehavioral development in the offspring; thus, the long-term benefits and safety of such supplementation are uncertain. Although it is clear that excessive iodine intake can cause alterations in thyroid function in susceptible individuals, safe upper limits for iodine intake in pregnancy have not been well defined. Well-designed, prospective, randomized controlled trials that examine the effects of iodine supplementation on maternal thyroid function and infant neurobehavioral development in mildly to moderately iodine-deficient pregnant women are urgently needed. In addition, clinical data on the effects of iodine excess in pregnant and lactating women are needed to inform

  9. Metal Big Area Additive Manufacturing: Process Modeling and Validation

    Energy Technology Data Exchange (ETDEWEB)

    Simunovic, Srdjan [ORNL; Nycz, Andrzej [ORNL; Noakes, Mark W [ORNL; Chin, Charlie [Dassault Systemes; Oancea, Victor [Dassault Systemes

    2017-01-01

    Metal Big Area Additive Manufacturing (mBAAM) is a new additive manufacturing (AM) technology for printing large-scale 3D objects. mBAAM is based on the gas metal arc welding process and uses a continuous feed of welding wire to manufacture an object. An electric arc forms between the wire and the substrate, which melts the wire and deposits a bead of molten metal along the predetermined path. In general, the welding process parameters and local conditions determine the shape of the deposited bead. The sequence of the bead deposition and the corresponding thermal history of the manufactured object determine the long range effects, such as thermal-induced distortions and residual stresses. Therefore, the resulting performance or final properties of the manufactured object are dependent on its geometry and the deposition path, in addition to depending on the basic welding process parameters. Physical testing is critical for gaining the necessary knowledge for quality prints, but traversing the process parameter space in order to develop an optimized build strategy for each new design is impractical by pure experimental means. Computational modeling and optimization may accelerate development of a build process strategy and saves time and resources. Because computational modeling provides these opportunities, we have developed a physics-based Finite Element Method (FEM) simulation framework and numerical models to support the mBAAM process s development and design. In this paper, we performed a sequentially coupled heat transfer and stress analysis for predicting the final deformation of a small rectangular structure printed using the mild steel welding wire. Using the new simulation technologies, material was progressively added into the FEM simulation as the arc weld traversed the build path. In the sequentially coupled heat transfer and stress analysis, the heat transfer was performed to calculate the temperature evolution, which was used in a stress analysis to

  10. Redox iodine and nitric acid absorbers

    Energy Technology Data Exchange (ETDEWEB)

    Stoker, D.J.; Rohrmann, C.A.

    1955-08-02

    A desirable radio-iodine emission goal for all HAPO has recently been set at one curie per day maximum. At the same time it was suggested that a more relaxed limit of ten curries per week with no more than three in any one day, would probably be satisfactory. To assure the achievement of these goal figures in the separations plants it was deemed necessary to either cool'' the irradiated material a greater length of time than is presently done before processing, or provide more efficient, iodine retention facilities. Increased power levels, higher production rates, and an increase in the awareness of radio-iodine emissions, have all coupled together to make present facilities generally inadequate when processing material aged less than about 100 days. Several alternate methods of providing additional iodine retention facilities for Redox were preliminarily scoped and presented for consideration. The purpose of this report is to present a scope design for improving iodine emission control at Redox.

  11. Iodine chemical forms in LWR severe accidents

    Energy Technology Data Exchange (ETDEWEB)

    Beahm, E.C.; Weber, C.F.; Kress, T.S.; Parker, G.W.

    1991-01-01

    Calculated data from seven severe accident sequences in light-water reactor plants were used to assess the chemical forms of iodine in containment. In most of the calculations for the seven sequences, iodine entering containment from the reactor coolant system was almost entirely in the form of CsI with very small contributions of I or HI. The largest fraction of iodine in forms other than CsI was a total of 3.2% as I plus HI. Within the containment, the CsI will deposit onto walls and other surfaces, as well as in water pools, largely in the form of iodide (I{sup {minus}}). The radiation induced conversion of I{sup {minus}} in water pools into I{sub 2} is strongly dependent on pH. In systems where the pH was controlled above 7, little additional elemental iodine would be produced in the containment atmosphere. When the pH falls below 7, it may be assumed that it is not being controlled, and large fractions of iodine as I{sub 2} within the containment atmosphere may be produced. 16 refs.

  12. Interactions of bromine, chlorine, and iodine photochemistry during ozone depletions in Barrow, Alaska

    Directory of Open Access Journals (Sweden)

    C. R. Thompson

    2014-11-01

    Full Text Available The springtime depletion of tropospheric ozone in the Arctic is known to be caused by active halogen photochemistry resulting from halogen atom precursors emitted from snow, ice, or aerosol surfaces. The role of bromine in driving ozone depletion events (ODEs has been generally accepted, but much less is known about the role of chlorine radicals in ozone depletion chemistry. While the potential impact of iodine in the High Arctic is more uncertain, there have been indications of active iodine chemistry through observed enhancements in filterable iodide, probable detection of tropospheric IO, and recently, detection of atmospheric I2. Despite decades of research, significant uncertainty remains regarding the chemical mechanisms associated with the bromine-catalyzed depletion of ozone, as well as the complex interactions that occur in the polar boundary layer due to halogen chemistry. To investigate this, we developed a zero-dimensional photochemical model, constrained with measurements from the 2009 OASIS field campaign in Barrow, Alaska. We simulated a 7 day period during late March that included a full ozone depletion event lasting 3 days and subsequent ozone recovery to study the interactions of halogen radicals under these different conditions. In addition, the effects of iodine added to our base model were investigated. While bromine atoms were primarily responsible for ODEs, chlorine and iodine were found to enhance the depletion rates and iodine was found to be more efficient per atom at depleting ozone than Br. The interaction between chlorine and bromine is complex, as the presence of chlorine can increase the recycling and production of Br atoms, while also increasing reactive bromine sinks under certain conditions. Chlorine chemistry was also found to have significant impacts on both HO2 and RO2. The results of this work highlight the need for future studies on the production mechanisms of Br2 and Cl2, as well as on the potential

  13. Geo-additive modelling of malaria in Burundi

    Directory of Open Access Journals (Sweden)

    Gebhardt Albrecht

    2011-08-01

    Full Text Available Abstract Background Malaria is a major public health issue in Burundi in terms of both morbidity and mortality, with around 2.5 million clinical cases and more than 15,000 deaths each year. It is still the single main cause of mortality in pregnant women and children below five years of age. Because of the severe health and economic burden of malaria, there is still a growing need for methods that will help to understand the influencing factors. Several studies/researches have been done on the subject yielding different results as which factors are most responsible for the increase in malaria transmission. This paper considers the modelling of the dependence of malaria cases on spatial determinants and climatic covariates including rainfall, temperature and humidity in Burundi. Methods The analysis carried out in this work exploits real monthly data collected in the area of Burundi over 12 years (1996-2007. Semi-parametric regression models are used. The spatial analysis is based on a geo-additive model using provinces as the geographic units of study. The spatial effect is split into structured (correlated and unstructured (uncorrelated components. Inference is fully Bayesian and uses Markov chain Monte Carlo techniques. The effects of the continuous covariates are modelled by cubic p-splines with 20 equidistant knots and second order random walk penalty. For the spatially correlated effect, Markov random field prior is chosen. The spatially uncorrelated effects are assumed to be i.i.d. Gaussian. The effects of climatic covariates and the effects of other spatial determinants are estimated simultaneously in a unified regression framework. Results The results obtained from the proposed model suggest that although malaria incidence in a given month is strongly positively associated with the minimum temperature of the previous months, regional patterns of malaria that are related to factors other than climatic variables have been identified

  14. Effects of 3,5-Diiodotyrosine and Potassium Iodide on Thyroid Function and Oxidative Stress in Iodine-Excess Wistar Rats.

    Science.gov (United States)

    Liu, Dan; Lin, Xinying; Yu, Fugui; Zhang, Man; Chen, Hongxia; Bao, Wei; Wang, Xia

    2015-12-01

    The objective of this study was to investigate the effects of organic iodine (3,5-diiodotyrosine, DIT) and inorganic iodine (potassium iodine, KI) on thyroid function and oxidative stress in iodine-excess Wistar rats. Seventy-two Wistar rats were randomly divided into eight groups: normal control (NC), thyroid tablet-induced hyperthyroidism model (HM), low DIT (L-DIT), medium DIT (M-DIT), high DIT (H-DIT), low KI (L-KI), medium KI (M-KI), and high KI (H-KI). All rats were fed ad libitum for 30 days. Morphological changes in the thyroid, absolute and relative weights of the thyroid, thyroid function markers free triiodothyronine (FT3) and free thyroxine (FT4), urinary iodine level, and oxidative stress indicators were measured. Compared to the HM groups, the FT3 and FT4 levels decreased in the L-DIT groups; the thyroid weight and thyroid weight/body weight values decreased markedly in the L-DIT and M-DIT groups; serum superoxide dismutase/malondialdehyde increased markedly; glutathione peroxidase activity increased markedly in the L-DIT groups; and malondialdehyde levels decreased significantly in the M-DIT groups. However, the FT3 and FT4 levels decreased and glutathione peroxidase levels increased significantly in the DIT groups compared to their corresponding KI groups. Additionally, urinary iodine levels increased significantly in both DIT and KI groups, while the highest urinary iodine excretion was showed in the DIT groups among groups. When the addition of iodine with the same doses in iodine-excess rats, although neither DIT nor KI normalized iodine levels in the iodine-excess rats, the DIT did less damage than did KI to thyroid follicular cells. Therefore, DIT rather than KI had a protective effect by balancing the antioxidant system when exposed to supraphysiological iodine. These suggest that DIT may be used as a new alternative iodized salt in the universal salt iodization to avoid the potential damage of surplus KI.

  15. The thyroid, iodine and autoimmunity

    NARCIS (Netherlands)

    P. Mooij (Petra)

    1993-01-01

    textabstractAn excessive dietary iodine intake has also been described to lead to thyroid autoimmune reactivity: a. in individuals with a preexisting thyroid abnormality, such as an iodine deficient goitre, an excessive dietary iodine intake results in a proportion of the individuals in the developm

  16. [Critical of the additive model of the randomized controlled trial].

    Science.gov (United States)

    Boussageon, Rémy; Gueyffier, François; Bejan-Angoulvant, Theodora; Felden-Dominiak, Géraldine

    2008-01-01

    Randomized, double-blind, placebo-controlled clinical trials are currently the best way to demonstrate the clinical effectiveness of drugs. Its methodology relies on the method of difference (John Stuart Mill), through which the observed difference between two groups (drug vs placebo) can be attributed to the pharmacological effect of the drug being tested. However, this additive model can be questioned in the event of statistical interactions between the pharmacological and the placebo effects. Evidence in different domains has shown that the placebo effect can influence the effect of the active principle. This article evaluates the methodological, clinical and epistemological consequences of this phenomenon. Topics treated include extrapolating results, accounting for heterogeneous results, demonstrating the existence of several factors in the placebo effect, the necessity to take these factors into account for given symptoms or pathologies, as well as the problem of the "specific" effect.

  17. QUALIMETRIC QUALITY ASSESSMENT OF IODINE SUPPLEMENTS

    Directory of Open Access Journals (Sweden)

    F. S. Bazrova

    2015-01-01

    Full Text Available The article discusses the new iodine-containing supplements (ID derived from organic media collagenous animal protein (pork rind, carpatina and collagen and protein concentrates brands SCANGEN and PROMIL C95. It is shown that the use of these proteins as carriers of iodine is due to the high content of the amino acids glycine and alanine, which correlates with the degree of binding of iodine objects. New additives in addition to the special focus improve rheological properties of foods, including texture, appearance and functional properties. To assess the quality'ID and selection of preferred option the proposed qualitative assessment and a systematic approach to consider all'ID as a system to allocate its elements, to justify the principles of its construction and the requirements imposed on it, to build a General decision tree. For the construction of complex criterion for assessing the quality'ID proposed procedure formalization based on selection and evaluation of individual indicators, the definition of the laws of their change, depending on the dose, duration and temperature of exposure, and functional efficiency. For comparative evaluation of single and calculation of group indicators all of them were reduced to a single dimension by introducing the dimensionless coefficients of adequately describing the analyzed indicators. The article presents the calculated values of single and group of indicators characterizing technological properties 'ID: the degree of binding of iodine, the binding rate of iodine, heat losses of iodine and basic functional and technological properties of meat stuffing systems (water-binding, moisture-holding, emulsifying capacity and emulsion stability, obtained by the introduction of stuffing in the system studied'ID. At the final stage is the selection of the best 'ID, on the basis of an assessment of group performance.

  18. Effects of diuretics on iodine uptake in non-toxic goitre: comparison with low-iodine diet

    Energy Technology Data Exchange (ETDEWEB)

    Kapucu, L.Ozlem; Azizoglu, Firat [Department of Nuclear Medicine, Gazi University, Ankara (Turkey); Ayvaz, Goksun; Karakoc, Ayhan [Department of Endocrinology, Gazi University, Ankara (Turkey)

    2003-09-01

    Low-iodine diet has been employed to achieve iodine depletion prior to radioiodine (RI) therapy. However, treatment with diuretics may be more effective than low-iodine diet in causing iodine depletion and subsequent increase in RI uptake by the thyroid. Fifty-five patients with non-toxic goitre were given 0.20 MBq RI p.o. on the first day of the study and thyroid uptake was measured. In 15 patients, a low-iodine diet was started and continued for 14 days. The remaining 40 patients received furosemide 40 mg/day orally for 5 days with an unrestricted diet. On the 15th day of the study, all patients were given 0.20 MBq RI p.o. and thyroid RI uptake was measured again. Additionally, 24-h urinary iodine excretion and RI clearance were measured on the 1st and 6th days in 21 patients from the furosemide group and on the 1st and 15th days in eight patients from the diet group. Furosemide administration led to a 58.40% increase in iodine uptake over the baseline value, which was significantly higher than the increase caused by low-iodine diet (17.22%) (P<0.0001). Urinary excretion of RI decreased in both groups similarly (furosemide, 29.45%; low-iodine diet, 21.06%; P=0.33). Iodine clearance also decreased in each group similarly (10.61% vs 7.53%, P=0.53). Treatment with furosemide prior to administration of RI increases the uptake of RI by the thyroid more effectively than does low-iodine diet. (orig.)

  19. Iodine and selenium in natural water, their fixation on geochemical barriers in soils and rocks and explanation of I and Se behavior in water-solid phase system using thermodynamic modeling

    Science.gov (United States)

    Korobova, Elena; Ryzhenko, Boris; Cherkasova, Elena; Sedykh, Ivelina; Korsakova, Nadezhda; Berezkin, Victor; Kolmykova, Lyudmila; Danilova, Valentina; Khushvakhtova, Sabzbakhor

    2014-05-01

    Iodine and selenium are essential for normal functioning of thyroid gland. Their natural deficiency in areas subjected to radioiodine contamination during nuclear tests and accidents may increase the risk of thyroid cancer among the most sensitive groups of population. Deficiency is caused by both the low abundance of microelements in the environmental components of the local food chain and their fixation on geochemical barriers due to such processes as chemical transformation, sorption, chemisorption, complexing. The studies of iodine and selenium distribution in soils, herbs and drinking water in rural settlements of the Bryansk oblast' confirmed low level of iodine and selenium content in local soils, plants and water and revealed different character of their distribution in soils and waters formed in geochemically different conditions of water migration in areas of fluvioglacial, moraine and loess-like soil forming rocks (the polesje, moraine and opolje landscapes correspondingly). Iodine content in top horizons of the soils developed on loess-like sediments and rich in organic matter was considerably higher as compared to those formed on sandy moraine or fluvioglacial sediments. For selenium the difference was not pronounced. Iodine was noted for positive correlation with Corg and fixation in the soil profile on carbonate barrier. A negative correlation was found between selenium content in grasses and in topsoil of subordinated elementary landscapes characterized by waterlogged and reduction conditions in soils. Thermodynamic modeling performed for 47 water samples on the basis of their chemical composition helped to explain the established patterns of iodine and selenium behavior in soil-water system. It demonstrated the possibility of existence of CaI+ and MgI+ complexes in water and sedimentation of FeSe(cr) in presence of a considerable amount of Fe2+. Iodine complexation with Ca and Mg ions may explain its further fixation on carbonate barrier in soils

  20. Versatility of cooperative transcriptional activation: a thermodynamical modeling analysis for greater-than-additive and less-than-additive effects.

    Directory of Open Access Journals (Sweden)

    Till D Frank

    Full Text Available We derive a statistical model of transcriptional activation using equilibrium thermodynamics of chemical reactions. We examine to what extent this statistical model predicts synergy effects of cooperative activation of gene expression. We determine parameter domains in which greater-than-additive and less-than-additive effects are predicted for cooperative regulation by two activators. We show that the statistical approach can be used to identify different causes of synergistic greater-than-additive effects: nonlinearities of the thermostatistical transcriptional machinery and three-body interactions between RNA polymerase and two activators. In particular, our model-based analysis suggests that at low transcription factor concentrations cooperative activation cannot yield synergistic greater-than-additive effects, i.e., DNA transcription can only exhibit less-than-additive effects. Accordingly, transcriptional activity turns from synergistic greater-than-additive responses at relatively high transcription factor concentrations into less-than-additive responses at relatively low concentrations. In addition, two types of re-entrant phenomena are predicted. First, our analysis predicts that under particular circumstances transcriptional activity will feature a sequence of less-than-additive, greater-than-additive, and eventually less-than-additive effects when for fixed activator concentrations the regulatory impact of activators on the binding of RNA polymerase to the promoter increases from weak, to moderate, to strong. Second, for appropriate promoter conditions when activator concentrations are increased then the aforementioned re-entrant sequence of less-than-additive, greater-than-additive, and less-than-additive effects is predicted as well. Finally, our model-based analysis suggests that even for weak activators that individually induce only negligible increases in promoter activity, promoter activity can exhibit greater-than-additive

  1. Iodine in soil

    Energy Technology Data Exchange (ETDEWEB)

    Johanson, Karl Johan [Swedish Univ. of Agricultural Sciences, Uppsala (Sweden). Dept. of Forest Mycology and Pathology

    2000-12-01

    A literature study of the migration and the appearance of iodine isotopes in the bio-sphere particularly in soil is presented. Some important papers in the field of iodine appearance in soil and the appearance of {sup 129}I in the surroundings of reprocessing plants are discussed. The most important conclusions are: 1. Iodine binds to organic matter in the soil and also to some oxides of aluminium and iron. 2. If the iodine is not bound to the soil a large fraction of added {sup 129}I is volatilized after a rather short period. 3. The binding and also the volatilisation seems to be due to biological activity in the soil. It may take place within living microorganisms or by external enzymes excreted from microorganisms. 4. Due to variations in the composition of soil there may be a large variation in the distribution of {sup 129}I in the vertical profile of soil - usually most of the {sup 129}I in the upper layer - which also results in large variations in the {sup 129}I uptake to plants.

  2. A nonparametric dynamic additive regression model for longitudinal data

    DEFF Research Database (Denmark)

    Martinussen, Torben; Scheike, Thomas H.

    2000-01-01

    dynamic linear models, estimating equations, least squares, longitudinal data, nonparametric methods, partly conditional mean models, time-varying-coefficient models......dynamic linear models, estimating equations, least squares, longitudinal data, nonparametric methods, partly conditional mean models, time-varying-coefficient models...

  3. Systematic review using meta-analyses to estimate dose-response relationships between iodine intake and biomarkers of iodine status in different population groups.

    Science.gov (United States)

    Ristić-Medić, Danijela; Dullemeijer, Carla; Tepsić, Jasna; Petrović-Oggiano, Gordana; Popović, Tamara; Arsić, Aleksandra; Glibetić, Marija; Souverein, Olga W; Collings, Rachel; Cavelaars, Adriënne; de Groot, Lisette; van't Veer, Pieter; Gurinović, Mirjana

    2014-03-01

    The objective of this systematic review was to identify studies investigating iodine intake and biomarkers of iodine status, to assess the data of the selected studies, and to estimate dose-response relationships using meta-analysis. All randomized controlled trials, prospective cohort studies, nested case-control studies, and cross-sectional studies that supplied or measured dietary iodine and measured iodine biomarkers were included. The overall pooled regression coefficient (β) and the standard error of β were calculated by random-effects meta-analysis on a double-log scale, using the calculated intake-status regression coefficient (β) for each individual study. The results of pooled randomized controlled trials indicated that the doubling of dietary iodine intake increased urinary iodine concentrations by 14% in children and adolescents, by 57% in adults and the elderly, and by 81% in pregnant women. The dose-response relationship between iodine intake and biomarkers of iodine status indicated a 12% decrease in thyroid-stimulating hormone and a 31% decrease in thyroglobulin in pregnant women. The model of dose-response quantification used to describe the relationship between iodine intake and biomarkers of iodine status may be useful for providing complementary evidence to support recommendations for iodine intake in different population groups.

  4. Direct evidence for coastal iodine particles from Laminaria macroalgae – linkage to emissions of molecular iodine

    Directory of Open Access Journals (Sweden)

    G. McFiggans

    2004-01-01

    Full Text Available Renewal of ultrafine aerosols in the marine boundary layer may lead to repopulation of the marine distribution and ultimately determine the concentration of cloud condensation nuclei (CCN. Thus the formation of nanometre-scale particles can lead to enhanced scattering of incoming radiation and a net cooling of the atmosphere. The recent demonstration of the chamber formation of new particles from the photolytic production of condensable iodine-containing compounds from diiodomethane (CH2I2, (O'Dowd et al., 2002; Kolb, 2002; Jimenez et al., 2003a; Burkholder and Ravishankara, 2003, provides an additional mechanism to the gas-to-particle conversion of sulphuric acid formed in the photo-oxidation of dimethylsulphide for marine aerosol repopulation. CH2I2 is emitted from seaweeds (Carpenter et al., 1999, 2000 and has been suggested as an initiator of particle formation. We demonstrate here for the first time that ultrafine iodine-containing particles are produced by intertidal macroalgae exposed to ambient levels of ozone. The particle composition is very similar both to those formed in the chamber photo-oxidation of diiodomethane and in the oxidation of molecular iodine by ozone. The particles formed in all three systems are similarly aspherical. When small, those formed in the molecular iodine system swell only moderately when exposed to increased humidity environments, and swell progressively less with increasing size; this behaviour occurs whether they are formed in dry or humid environments, in contrast to those in the CH2I2 system. Direct coastal boundary layer observations of molecular iodine, ultrafine particle production and iodocarbons are reported. Using a newly measured molecular iodine photolysis rate, it is shown that, if atomic iodine is involved in the observed particle bursts, it is of the order of at least 1000 times more likely to result from molecular iodine photolysis than diiodomethane photolysis. A hypothesis for molecular

  5. Zero-valent iron pretreatment for detoxifying iodine in liquid crystal display (LCD) manufacturing wastewater.

    Science.gov (United States)

    Lee, J W; Cha, D K; Oh, Y K; Ko, K B; Song, J S

    2009-05-15

    This study investigated reductive transformation of iodine by zero-valent iron (ZVI), and the subsequent detoxification of iodine-laden wastewater. ZVI completely reduced aqueous iodine to non-toxic iodide. Respirometric bioassay illustrated that the presence of iodine increase the lag phase before the onset of oxygen consumption. The length of lag phase was proportional to increasing iodine dosage. The reduction products of iodine by ZVI did not exhibit any inhibitory effect on the biodegradation. The cumulative biological oxidation associated with iodine toxicity was closely fitted to Gompertz model. When iodine-laden wastewater was continuously fed to a bench-scale activated sludge unit, chemical oxygen demand (COD) removal efficiencies decreased from above 90% to below 80% along with a marked decrease in biomass concentration. On the other hand, the COD removal efficiency and biomass concentration remained constant in the integrated ZVI-activated sludge system. Respirometric bioassay with real iodine-laden LCD manufacturing wastewater demonstrated that ZVI was effective for detoxifying iodine and consequently enhancing biodegradability of wastewater. This result suggested that ZVI pretreatment may be a feasible option for the removal of iodine in LCD processing wastewater, instead of more costly processes such as adsorption and chemical oxidation, which are commonly in the iodine-laden LCD wastewater treatment facility.

  6. Perchlorate, iodine supplements, iodized salt and breast milk iodine content

    Energy Technology Data Exchange (ETDEWEB)

    Kirk, Andrea B. [Department of Epidemiology, School of Public Health, University of North Texas Health Sciences Center, 3500 Camp Bowie Blvd., Fort Worth, TX 76107 (United States); Kroll, Martina; Dyke, Jason V.; Ohira, Shin-Ichi; Dias, Rukshan A.; Dasgupta, Purnendu K. [Department of Chemistry and Biochemistry, 700 Planetarium Place, University of Texas at Arlington, Arlington, TX 76019 (United States)

    2012-03-15

    This study was undertaken to determine if increasing maternal iodine intake through single dose tablets will decrease breast milk concentrations of the iodine-uptake inhibitor, perchlorate, through competitive inhibition. We also sought to determine if the timing of supplementation influences the fraction of iodine excreted in milk versus urine and to compare the effectiveness of iodized salt as a means of providing iodine to breastfed infants. Thirteen women who did not use supplements, seven of whom used iodized salt and six of whom used non-iodized salt, submitted four milk samples and a 24-h urine collection daily for three days. Women repeated the sampling protocol for three more days during which {approx} 150 {mu}g of iodine were taken in the evening and again for three days with morning supplementation. Samples were analyzed using isotope-dilution inductively-coupled plasma-mass spectrometry for iodine and isotope-dilution ion chromatography-tandem mass spectrometry for perchlorate. No statistically significant differences were observed in milk iodine or perchlorate concentrations during the two treatment periods. Estimated perchlorate intake was above the U.S. National Academy of Sciences suggested reference dose for most infants. Single daily dose iodine supplementation was not effective in decreasing milk perchlorate concentrations. Users of iodized salt had significantly higher iodine levels in milk than non-users. Iodized salt may be a more effective means of iodine supplementation than tablets. - Highlights: Black-Right-Pointing-Pointer Estimated infant exposures to perchlorate were, on a {mu}g/kg basis, {approx} 5 Multiplication-Sign higher than those of mothers. Black-Right-Pointing-Pointer Daily supplements are less effective than iodized salt in providing iodine to lactating women. Black-Right-Pointing-Pointer Low iodine and high perchlorate in milk may place infants at risk of iodine deficiency.

  7. A Model to Predict Total Chlorine Residue in the Cooling Seawater of a Power Plant Using Iodine Colorimetric Method

    Directory of Open Access Journals (Sweden)

    Pei-Jie Meng

    2008-04-01

    Full Text Available A model experiment monitoring the fate of total residue oxidant (TRO in water at a constant temperature and salinity indicated that it decayed exponentially with time, and with TRO decaying faster in seawater than in distilled water. The reduction of TRO by temperature (°K was found to fit a curvilinear relationship in distilled water (r2 = 0.997 and a linear relationship in seawater (r2 = 0.996. Based on the decay rate, flow rate, and the length of cooling water flowing through at a given temperature, the TRO level in the cooling water of a power plant could be estimated using the equation developed in this study. This predictive model would provide a benchmark for power plant operators to adjust the addition of chlorine to levels necessary to control bio-fouling of cooling water intake pipelines, but without irritating ambient marine organisms.

  8. A Model to Predict Total Chlorine Residue in the Cooling Seawater of a Power Plant Using Iodine Colorimetric Method

    Science.gov (United States)

    Wang, Jih-Terng; Chen, Ming-Hui; Lee, Hung-Jen; Chang, Wen-Been; Chen, Chung-Chi; Pai, Su-Cheng; Meng, Pei-Jie

    2008-01-01

    A model experiment monitoring the fate of total residue oxidant (TRO) in water at a constant temperature and salinity indicated that it decayed exponentially with time, and with TRO decaying faster in seawater than in distilled water. The reduction of TRO by temperature (°K) was found to fit a curvilinear relationship in distilled water (r2 = 0.997) and a linear relationship in seawater (r2 = 0.996). Based on the decay rate, flow rate, and the length of cooling water flowing through at a given temperature, the TRO level in the cooling water of a power plant could be estimated using the equation developed in this study. This predictive model would provide a benchmark for power plant operators to adjust the addition of chlorine to levels necessary to control bio-fouling of cooling water intake pipelines, but without irritating ambient marine organisms. PMID:19325768

  9. Iodine speciation in rain, snow and aerosols and possible transfer of organically bound iodine species from aerosol to droplet phases

    Directory of Open Access Journals (Sweden)

    B. S. Gilfedder

    2008-04-01

    Full Text Available Iodine oxides, such as iodate, should theoretically be the only stable sink species for iodine in the troposphere. However, field observations have increasingly found very little iodate and significant amounts of iodide and organically bound iodine in precipitation and aerosols. The aim of this study was to investigate iodine speciation, including the organic fraction, in rain, snow, and aerosols in an attempt to further clarify aqueous phase iodine chemistry. Diurnal aerosol samples were taken with a 5 stage cascade impactor and a virtual impactor (PM2.5 from the Mace Head research station, Ireland, during summer 2006. Rain was collected from Australia, New Zealand, Patagonia, Germany, Ireland, and Switzerland while snow was obtained from Greenland, Germany, Switzerland, and New Zealand. All samples were analysed for total iodine by inductively coupled plasma mass spectrometry (ICP-MS and speciation was determined by coupling an ion chromatography unit to the ICP-MS. Total iodine in the aerosols from Mace Head gave a median concentration of 50 pmol m−3 of which the majority was associated with the organic fraction (median day: 91±7%, night: 94±6% of total iodine. Iodide exhibited higher concentrations than iodate (median 5% vs. 0.8% of total iodine, and displayed significant enrichment during the day compared to the night. Interestingly, up to 5 additional, presumably anionic organic peaks were observed in all IC-ICP-MS chromatograms, composing up to 15% of the total iodine. Organically bound iodine was also the dominant fraction in all rain and snow samples, with lesser amounts of iodide and iodate (iodate was particularly low in snow. Two of the same unidentified peaks found in aerosols were also observed in precipitation from both Southern and Northern Hemispheres, suggesting that these species are transferred from the aerosol phase into precipitation. It is suggested that organo-I is formed by reactions between HOI

  10. Percolation model with an additional source of disorder

    Science.gov (United States)

    Kundu, Sumanta; Manna, S. S.

    2016-06-01

    The ranges of transmission of the mobiles in a mobile ad hoc network are not uniform in reality. They are affected by the temperature fluctuation in air, obstruction due to the solid objects, even the humidity difference in the environment, etc. How the varying range of transmission of the individual active elements affects the global connectivity in the network may be an important practical question to ask. Here a model of percolation phenomena, with an additional source of disorder, is introduced for a theoretical understanding of this problem. As in ordinary percolation, sites of a square lattice are occupied randomly with probability p . Each occupied site is then assigned a circular disk of random value R for its radius. A bond is defined to be occupied if and only if the radii R1 and R2 of the disks centered at the ends satisfy a certain predefined condition. In a very general formulation, one divides the R1-R2 plane into two regions by an arbitrary closed curve. One defines a point within one region as representing an occupied bond; otherwise it is a vacant bond. The study of three different rules under this general formulation indicates that the percolation threshold always varies continuously. This threshold has two limiting values, one is pc(sq) , the percolation threshold for the ordinary site percolation on the square lattice, and the other is unity. The approach of the percolation threshold to its limiting values are characterized by two exponents. In a special case, all lattice sites are occupied by disks of random radii R ∈{0 ,R0} and a percolation transition is observed with R0 as the control variable, similar to the site occupation probability.

  11. Iodine Status in Pregnant & Breastfeeding Women

    DEFF Research Database (Denmark)

    Andersen, Stine Linding

    Iodine is required for the synthesis of thyroid hormones, which are crucial regulator of early brain development. The source of iodine in the fetus and the breastfed infant is maternal iodine, and adequate iodine intake in pregnant and breastfeeding is of major concern. Severe iodine deficiency can...... cause irreversible brain damage, whereas the consequences of mild to moderate iodine deficiency are less clear. Denmark was previously iodine deficient with regional differences (mild iodine deficiency in East Denmark and moderate iodine deficiency in West Denmark), and also pregnant and breastfeeding...... women suffered from iodine deficiency. A mandatory iodine fortification of household salt and salt used for commercial production of bread was introduced in Denmark in the year 2000. The PhD thesis investigates intake of iodine supplements and urinary iodine status in Danish pregnant and breastfeeding...

  12. Hyperbolic value addition and general models of animal choice.

    Science.gov (United States)

    Mazur, J E

    2001-01-01

    Three mathematical models of choice--the contextual-choice model (R. Grace, 1994), delay-reduction theory (N. Squires & E. Fantino, 1971), and a new model called the hyperbolic value-added model--were compared in their ability to predict the results from a wide variety of experiments with animal subjects. When supplied with 2 or 3 free parameters, all 3 models made fairly accurate predictions for a large set of experiments that used concurrent-chain procedures. One advantage of the hyperbolic value-added model is that it is derived from a simpler model that makes accurate predictions for many experiments using discrete-trial adjusting-delay procedures. Some results favor the hyperbolic value-added model and delay-reduction theory over the contextual-choice model, but more data are needed from choice situations for which the models make distinctly different predictions.

  13. MULTIVARIATE ANALYSIS OF RELATIONSHIPS BETWEEN IODINE BIOLOGICAL EXPOSURE AND SUBCLINICAL THYROID DYSFUNCTIONS

    Institute of Scientific and Technical Information of China (English)

    Wei Chong; Zhong-yan Shan; Wei Sun; Wei-ping Teng

    2005-01-01

    Objective To assess the relationships between iodine biological exposure and subclinical thyroid dysfunctions. Methods The cross-sectional survey was performed to obtain the epidemiologic data of population in three communities with different iodine biological exposure: mild iodine deficiency [median urinary iodine concentration (MUI) of 50 99g/L], more than adequate iodine intake (MUI of 200-299 μg/L), and excessive iodine intake (MUI over 300 μg/L). Univariate and multivariate analysis (logistic regression analysis) were used to analyze the risk factors of subclinical hypothyroidism and subclinical hyperthyroidism. Results Logistic regression analysis with sex and age controlled suggested that more than adequate iodine intake (OR = 3.172, P = 0.0004) and excessive iodine intake (OR = 6.391, P = 0.0001) increased the risk of subclinical hypothyroidism, while excessive iodine intake decreased the risk of subclinical hyperthyroidism (OR = 0.218, P= 0.0001). Logistic regression analysis including interaction of iodine intake and antibodies [tryroid peroxidase antibody (TPOAb) and thyroglobulin antibody (TgAb)] suggested that excessive iodine intake was an independent risk factor of subclinical hypothyroidism (OR = 6.360, P = 0.0001), but independent protect factor of subclinical hyperthyroidism (OR = 0.193, P = 0.0001). More than adequate iodine intake and it's interaction with TgAb increased the risk of subclinical hypothyroidism independently, in addition, it decreased the risk of subclinical hyperthyroidism at the present of TPOAb. Conclusion Both excessive iodine intake and more than adequate iodine intake could increase risk of subclinical hypo thyroidism, supplement of iodine should be controlled to ensure MUI within the safe range.

  14. Simulation of total dietary iodine intake in Flemish preschool children.

    Science.gov (United States)

    Vandevijvere, Stefanie; Lin, Y; Moreno-Reyes, R; Huybrechts, I

    2012-08-01

    The aim of the present study was to calculate the distribution of total iodine intake among Flemish preschoolers and to identify the major sources contributing to iodine intake. A simulation model using a combination of deterministic and probabilistic techniques was utilised. Scenario analyses were performed to assess iodine intake via dairy products, industrially added iodised salt in bread and discretionarily added iodised household salt. Relevant data from 3-d estimated dietary records of 696 preschoolers 2·5-6·5 years old were used. Usual iodine intakes were calculated using the Iowa State University method. With a more generalised utilisation of iodised salt in bread (44 % of the bakers in 2011 instead of 12 % in 2002), mean iodine intake increased from 159 to 164 μg/d using the McCance and Widdowson's food composition table and from 104 to 109 μg/d using the German food composition table. The percentage of preschoolers with an iodine intake below the estimated average requirement (65 μg/d) decreased from 5-12 to 4-9 %, while the percentage of preschoolers with an iodine intake above the tolerable upper intake level (300 μg/d) remained constant (0·3-4 %). Mean iodine intake via food supplements was 4·2 μg/d (total population) and 16·9 μg/d (consumers only). Both in 2002 and 2011, sugared dairy products, milk and iodised salt (21·4, 13·1, and 8·7 %, respectively in 2011) were the main contributors to total iodine intake. In conclusion, dietary iodine intake could still be improved in Flemish preschoolers. The use of adequately iodised household salt and the more generalised use of iodised salt by bakers should be further encouraged.

  15. Effect of iodine contrast agent concentration on cerebrovascular dose for synchrotron radiation microangiography based on a simple mouse head model and a voxel mouse head phantom by Monte Carlo simulation.

    Science.gov (United States)

    Lin, Hui; Jing, Jia; Lu, Yi-Fan; Xie, Cong; Lin, Xiao-Jie; Yang, Guo-Yuan

    2016-01-01

    Effective setting strategies using Monte Carlo simulation are presented to mitigate the irradiation damage in synchrotron radiation microangiography (SRA). A one-dimensional mouse head model and a segmented voxel phantom mouse head were simulated using the EGSnrc/DOSXYZnrc code to investigate the dose enhancement effect of an iodine contrast agent irradiated by a monochromatic synchrotron radiation source. The influence of the iodine concentration, vessel width and depth, protection with and without the skull layer, and various incident X-ray energies were all simulated. The dose enhancement effect and the absolute dose based on the segmented voxel mouse head phantom were evaluated. The dose enhancement ratio depended little on the irradiation depth, but strongly and linearly increasing on iodine concentration. The protection given by the skull layer cannot be ignored in SRA because a 700 µm-thick skull can decrease the dose by 10%. The incident X-ray energy can affect the dose significantly. Compared with a dose of 33.2 keV for 50 mgI ml(-1), a dose of 32.7 keV decreased by 38%, whereas a dose of 33.7 keV increased by 69.2% and the variation strengthened more with enhanced iodine concentration. The segmented voxel mouse head phantom also showed that the average dose enhancement effect and the maximal voxel dose per photon depended little on the iodine voxel volume ratio but strongly on the iodine concentration. To decrease the damage caused by the dose in SRA, a high-Z contrast agent should be used as little as possible and irradiation of the injection site of the contrast agent should be avoided immediately after the injection. The fragile vessel containing iodine should avoid being closely irradiated. Avoiding irradiating through a thin (or no) skull region, or attaching a thin equivalent material on the outside for protection are better methods. An incident X-ray energy as low as possible should be used as long as the SRA image quality is ensured

  16. Iodine deficiency disorders in the iodine-replete environment.

    Science.gov (United States)

    Nyenwe, Ebenezer A; Dagogo-Jack, Samuel

    2009-01-01

    Iodine deficiency disorders (IDD) constitute significant public health problems in parts of the world with poor iodine nutrition, but have been eradicated in North America and other regions. We herein report 3 cases of IDD, which occurred in women living in iodine-replete environments. The clinical presentation, biochemical findings, and radiological features of the patients were analyzed and presented in 3 case reports. The radiological features are illustrated in sonographic and scintigraphic images. A literature review and discussion, which highlight the risk factors, pathogenesis, ancillary investigations, and rational treatment of iodine deficiency goiter and hypothyroidism are provided. All 3 patients were young women, aged 24 to 38 years, who had goiter. Two of them presented with goitrous hypothyroidism. Radioactive iodine scintigraphy showed a characteristic finding of diffusely increased uptake (in the absence of clinical and biochemical evidence of hyperthyroidism). This scintigraphic pattern was found to be pathognomonic. Dietary iodine supplementation alone resulted in complete remission of IDD in the subjects, including the 2 patients with hypothyroidism. IDD can occur in iodine-replete environments. A high index of suspicion is needed to recognize these cases. It is pertinent that the correct diagnosis be made to avoid unwarranted life-long thyroxine therapy in patients presenting with goiter and hypothyroidism, which is easily treatable with iodized salt. These cases underscore the need for considering iodine deficiency in the etiologic diagnosis of goiter and hypothyroidism, even in iodine-sufficient regions.

  17. An Increase in Consuming Adequately Iodized Salt May Not Be Enough to Rectify Iodine Deficiency in Pregnancy in an Iodine-Sufficient Area of China

    Science.gov (United States)

    Wang, Zhifang; Zhu, Wenming; Mo, Zhe; Wang, Yuanyang; Mao, Guangming; Wang, Xiaofeng; Lou, Xiaoming

    2017-01-01

    Universal salt iodization (USI) has been implemented for two decades in China. It is crucial to periodically monitor iodine status in the most vulnerable population, such as pregnant women. A cross-sectional study was carried out in an evidence-proved iodine-sufficient province to evaluate iodine intake in pregnancy. According to the WHO/UNICEF/ICCIDD recommendation criteria of adequate iodine intake in pregnancy (150–249 µg/L), the median urinary iodine concentration (UIC) of the total 8159 recruited pregnant women was 147.5 µg/L, which indicated pregnant women had iodine deficiency at the province level. Overall, 51.0% of the total study participants had iodine deficiency with a UIC < 150 µg/L and only 32.9% of them had adequate iodine. Participants living in coastal areas had iodine deficiency with a median UIC of 130.1 µg/L, while those in inland areas had marginally adequate iodine intake with a median UIC of 158.1 µg/L (p < 0.001). Among the total study participants, 450 pregnant women consuming non-iodized salt had mild-moderate iodine deficiency with a median UIC of 99.6 µg/L; 7363 pregnant women consuming adequately iodized salt had a lightly statistically higher median UIC of 151.9 µg/L, compared with the recommended adequate level by the WHO/UNICEF/ICCIDD (p < 0.001). Consuming adequately iodized salt seemed to lightly increase the median UIC level, but it may not be enough to correct iodine nutrition status to an optimum level as recommended by the WHO/UNICEF/ICCIDD. We therefore suggest that, besides strengthening USI policy, additional interventive measure may be needed to improve iodine intake in pregnancy. PMID:28230748

  18. Entrapment of iodine with cyclodextrins: Potential application of cyclodextrins in nuclear waste management

    Energy Technology Data Exchange (ETDEWEB)

    Szente, L.; Fenyvesi, E.; Szejtli, J.

    1999-12-15

    Cyclodextrins form inclusion complexes with iodine, which makes them candidates for iodine-sorption from nuclear waste gases. In model experiments it was shown that cyclodextrin-containing aqueous solutions and cross-linked cyclodextrin polymers were selective and effective iodine absorbers. Especially the {alpha}-cyclodextrin derivatives (methylated and cross-linked) have high sorption capacity. A correlation between the iodine sorption of the cyclodextrin solutions and the apparent association constant of the iodine/cyclodextrin complexes was found. On the basis of the results the binding of elemental and organic iodine emitted into the air by chemical and nuclear power plants can be made effectively by immobilizing iodine vapor in aqueous cyclodextrin solutions or in cyclodextrin polymer gel beds. Such new sorbents can be employed in the air filtration systems.

  19. Additive manufacturing for consumer-centric business models

    DEFF Research Database (Denmark)

    Bogers, Marcel; Hadar, Ronen; Bilberg, Arne

    2016-01-01

    and capturing value. In this paper, we explore the implications that AM technologies have for manufacturing systems in the new business models that they enable. In particular, we consider how a consumer goods manufacturer can organize the operations of a more open business model when moving from a manufacturer...

  20. Iodine Plasma Species Measurements in a Hall Effect Thruster Plume

    Science.gov (United States)

    2013-05-01

    60 90 0 2 4 6 8 Current (mA/cm^2) A n g l e ( d e g ) Xenon Iodine 500 V, 2 A, I2 Presented at 2012 JPC 33 Distribution A: Approved for public...Over 1 hour of operation on iodineAdditional 1/2 hour with thruster flowing Xe – Current up to ~50 A into anode Presented at 2012 JPC

  1. Iodine neutron capture therapy

    Science.gov (United States)

    Ahmed, Kazi Fariduddin

    A new technique, Iodine Neutron Capture Therapy (INCT) is proposed to treat hyperthyroidism in people. Present thyroid therapies, surgical removal and 131I treatment, result in hypothyroidism and, for 131I, involve protracted treatment times and excessive whole-body radiation doses. The new technique involves using a low energy neutron beam to convert a fraction of the natural iodine stored in the thyroid to radioactive 128I, which has a 24-minute half-life and decays by emitting 2.12-MeV beta particles. The beta particles are absorbed in and damage some thyroid tissue cells and consequently reduce the production and release of thyroid hormones to the blood stream. Treatment times and whole-body radiation doses are thus reduced substantially. This dissertation addresses the first of the several steps needed to obtain medical profession acceptance and regulatory approval to implement this therapy. As with other such programs, initial feasibility is established by performing experiments on suitable small mammals. Laboratory rats were used and their thyroids were exposed to the beta particles coming from small encapsulated amounts of 128I. Masses of 89.0 mg reagent-grade elemental iodine crystals have been activated in the ISU AGN-201 reactor to provide 0.033 mBq of 128I. This activity delivers 0.2 Gy to the thyroid gland of 300-g male rats having fresh thyroid tissue masses of ˜20 mg. Larger iodine masses are used to provide greater doses. The activated iodine is encapsulated to form a thin (0.16 cm 2/mg) patch that is then applied directly to the surgically exposed thyroid of an anesthetized rat. Direct neutron irradiation of a rat's thyroid was not possible due to its small size. Direct in-vivo exposure of the thyroid of the rat to the emitted radiation from 128I is allowed to continue for 2.5 hours (6 half-lives). Pre- and post-exposure blood samples are taken to quantify thyroid hormone levels. The serum T4 concentration is measured by radioimmunoassay at

  2. Additive Manufacturing of Anatomical Models from Computed Tomography Scan Data.

    Science.gov (United States)

    Gür, Y

    2014-12-01

    The purpose of the study presented here was to investigate the manufacturability of human anatomical models from Computed Tomography (CT) scan data via a 3D desktop printer which uses fused deposition modelling (FDM) technology. First, Digital Imaging and Communications in Medicine (DICOM) CT scan data were converted to 3D Standard Triangle Language (STL) format by using In Vaselius digital imaging program. Once this STL file is obtained, a 3D physical version of the anatomical model can be fabricated by a desktop 3D FDM printer. As a case study, a patient's skull CT scan data was considered, and a tangible version of the skull was manufactured by a 3D FDM desktop printer. During the 3D printing process, the skull was built using acrylonitrile-butadiene-styrene (ABS) co-polymer plastic. The printed model showed that the 3D FDM printing technology is able to fabricate anatomical models with high accuracy. As a result, the skull model can be used for preoperative surgical planning, medical training activities, implant design and simulation to show the potential of the FDM technology in medical field. It will also improve communication between medical stuff and patients. Current result indicates that a 3D desktop printer which uses FDM technology can be used to obtain accurate anatomical models.

  3. Modeling continuous self-report measures of perceived emotion using generalized additive mixed models.

    Science.gov (United States)

    McKeown, Gary J; Sneddon, Ian

    2014-03-01

    Emotion research has long been dominated by the "standard method" of displaying posed or acted static images of facial expressions of emotion. While this method has been useful, it is unable to investigate the dynamic nature of emotion expression. Although continuous self-report traces have enabled the measurement of dynamic expressions of emotion, a consensus has not been reached on the correct statistical techniques that permit inferences to be made with such measures. We propose generalized additive models and generalized additive mixed models as techniques that can account for the dynamic nature of such continuous measures. These models allow us to hold constant shared components of responses that are due to perceived emotion across time, while enabling inference concerning linear differences between groups. The generalized additive mixed model approach is preferred, as it can account for autocorrelation in time series data and allows emotion decoding participants to be modeled as random effects. To increase confidence in linear differences, we assess the methods that address interactions between categorical variables and dynamic changes over time. In addition, we provide comments on the use of generalized additive models to assess the effect size of shared perceived emotion and discuss sample sizes. Finally, we address additional uses, the inference of feature detection, continuous variable interactions, and measurement of ambiguity.

  4. Non-additive model for specific heat of electrons

    Science.gov (United States)

    Anselmo, D. H. A. L.; Vasconcelos, M. S.; Silva, R.; Mello, V. D.

    2016-10-01

    By using non-additive Tsallis entropy we demonstrate numerically that one-dimensional quasicrystals, whose energy spectra are multifractal Cantor sets, are characterized by an entropic parameter, and calculate the electronic specific heat, where we consider a non-additive entropy Sq. In our method we consider an energy spectra calculated using the one-dimensional tight binding Schrödinger equation, and their bands (or levels) are scaled onto the [ 0 , 1 ] interval. The Tsallis' formalism is applied to the energy spectra of Fibonacci and double-period one-dimensional quasiperiodic lattices. We analytically obtain an expression for the specific heat that we consider to be more appropriate to calculate this quantity in those quasiperiodic structures.

  5. Richly parameterized linear models additive, time series, and spatial models using random effects

    CERN Document Server

    Hodges, James S

    2013-01-01

    A First Step toward a Unified Theory of Richly Parameterized Linear ModelsUsing mixed linear models to analyze data often leads to results that are mysterious, inconvenient, or wrong. Further compounding the problem, statisticians lack a cohesive resource to acquire a systematic, theory-based understanding of models with random effects.Richly Parameterized Linear Models: Additive, Time Series, and Spatial Models Using Random Effects takes a first step in developing a full theory of richly parameterized models, which would allow statisticians to better understand their analysis results. The aut

  6. Additional Research Needs to Support the GENII Biosphere Models

    Energy Technology Data Exchange (ETDEWEB)

    Napier, Bruce A.; Snyder, Sandra F.; Arimescu, Carmen

    2013-11-30

    In the course of evaluating the current parameter needs for the GENII Version 2 code (Snyder et al. 2013), areas of possible improvement for both the data and the underlying models have been identified. As the data review was implemented, PNNL staff identified areas where the models can be improved both to accommodate the locally significant pathways identified and also to incorporate newer models. The areas are general data needs for the existing models and improved formulations for the pathway models. It is recommended that priorities be set by NRC staff to guide selection of the most useful improvements in a cost-effective manner. Suggestions are made based on relatively easy and inexpensive changes, and longer-term more costly studies. In the short term, there are several improved model formulations that could be applied to the GENII suite of codes to make them more generally useful. • Implementation of the separation of the translocation and weathering processes • Implementation of an improved model for carbon-14 from non-atmospheric sources • Implementation of radon exposure pathways models • Development of a KML processor for the output report generator module data that are calculated on a grid that could be superimposed upon digital maps for easier presentation and display • Implementation of marine mammal models (manatees, seals, walrus, whales, etc.). Data needs in the longer term require extensive (and potentially expensive) research. Before picking any one radionuclide or food type, NRC staff should perform an in-house review of current and anticipated environmental analyses to select “dominant” radionuclides of interest to allow setting of cost-effective priorities for radionuclide- and pathway-specific research. These include • soil-to-plant uptake studies for oranges and other citrus fruits, and • Development of models for evaluation of radionuclide concentration in highly-processed foods such as oils and sugars. Finally, renewed

  7. The additive hazards model with high-dimensional regressors

    DEFF Research Database (Denmark)

    Martinussen, Torben; Scheike, Thomas

    2009-01-01

    model. A standard PLS algorithm can also be constructed, but it turns out that the resulting predictor can only be related to the original covariates via time-dependent coefficients. The methods are applied to a breast cancer data set with gene expression recordings and to the well known primary biliary...

  8. Generalized Additive Models, Cubic Splines and Penalized Likelihood.

    Science.gov (United States)

    1987-05-22

    in case control studies ). All models in the table include dummy variable to account for the matching. The first 3 lines of the table indicate that OA...Ausoc. Breslow, N. and Day, N. (1980). Statistical methods in cancer research, volume 1- the analysis of case - control studies . International agency

  9. Multiple Imputation of Predictor Variables Using Generalized Additive Models

    NARCIS (Netherlands)

    de Jong, Roel; van Buuren, Stef; Spiess, Martin

    2016-01-01

    The sensitivity of multiple imputation methods to deviations from their distributional assumptions is investigated using simulations, where the parameters of scientific interest are the coefficients of a linear regression model, and values in predictor variables are missing at random. The performanc

  10. Effect of Dietary Intake of Stable Iodine on Dose-per-unit-intake Factors for 99Tc

    Energy Technology Data Exchange (ETDEWEB)

    Strom, Daniel J.

    2003-09-30

    It is well-known that the human thyroid concentrates iodine more than 100 times the concentration in plasma. Also well-known is the fact that large amounts of stable iodine in the diet can limit thyroid uptake of total iodine; this is the basis for administering potassium iodide following a release of radioiodine from a nuclear reactor accident or nuclear weapon detonation. Many researchers have shown enhanced concentrations of both organic and inorganic iodine in saliva and breast milk. Technetium-99 is a long-lived (231,000 year half-life) radionuclide of concern in the management of high-level radioactive waste. There is no doubt that 99Tc, if it is in groundwater, will be found in the chemical form of pertechnetate, 99TcO4?. Pertechnetate is a large anion, almost identical in size to iodide, I?. The nuclear medicine literature shows that pertechnetate concentrates in the thyroid, salivary glands, and lactating breast in addition to the stomach, liver, and alimentary tract as currently recognized by the International Commission on Radiological Protection (ICRP). The fact that large intakes of stable iodine (127I) in the diet limit uptake of iodine by the thyroid leads one to generalize that stable iodine in the diet may also limit thyroid uptake of pertechnetate. While there is at least one report that iodine in the diet blocks uptake of 99mTcO4? by the thyroid and salivary glands (which have the same Na/I symporter, the biochemical concentration mechanism), the level of protective effect seen for blocking radioactive iodine is not expected for 99TcO4? because pertechnetate does not become organically bound in the thyroid and thus is not retained for months the way iodide is. While it does account for Tc concentration in the thyroid, the existing ICRP biokinetic model for technetium does not take enhanced concentrations in salivary gland and breast tissue into account. From the survey of the nuclear medicine literature, it is not possible to compute the effect

  11. Iodine excess as an environmental risk factor for autoimmune thyroid disease.

    Science.gov (United States)

    Luo, Yuqian; Kawashima, Akira; Ishido, Yuko; Yoshihara, Aya; Oda, Kenzaburo; Hiroi, Naoki; Ito, Tetsuhide; Ishii, Norihisa; Suzuki, Koichi

    2014-07-21

    The global effort to prevent iodine deficiency disorders through iodine supplementation, such as universal salt iodization, has achieved impressive progress during the last few decades. However, iodine excess, due to extensive environmental iodine exposure in addition to poor monitoring, is currently a more frequent occurrence than iodine deficiency. Iodine excess is a precipitating environmental factor in the development of autoimmune thyroid disease. Excessive amounts of iodide have been linked to the development of autoimmune thyroiditis in humans and animals, while intrathyroidal depletion of iodine prevents disease in animal strains susceptible to severe thyroiditis. Although the mechanisms by which iodide induces thyroiditis are still unclear, several mechanisms have been proposed: (1) excess iodine induces the production of cytokines and chemokines that can recruit immunocompetent cells to the thyroid; (2) processing excess iodine in thyroid epithelial cells may result in elevated levels of oxidative stress, leading to harmful lipid oxidation and thyroid tissue injuries; and (3) iodine incorporation in the protein chain of thyroglobulin may augment the antigenicity of this molecule. This review will summarize the current knowledge regarding excess iodide as an environmental toxicant and relate it to the development of autoimmune thyroid disease.

  12. Iodine and Iron Deficiency in Mild Iodine Deficiency Region Under Iodine Supplementation

    Directory of Open Access Journals (Sweden)

    L Suplotova

    2005-03-01

    Full Text Available Objectives: Studying epidemiological criteria deficiency of iron and iodine at the population of Tyumen, on a background of iodine preventive maintenance. Methods: Because iron deficiency may impair the efficacy of iodine supplementation, the aim of this study was to determine the relation between serum ferritin and goiter, urinary iodine following iodized salt supplementation. Schoolboys are included in conformity to recommendations the WHO (1997 in 9—12 years old children (n = 435.. Results: On a background of preventive actions at the Tyumen schoolboys sufficient iodine maintenance (frequency of a craw is determined according to ultrasonic — 1.9%, a median urinary iodine — 113 mkg/l. The average level serum iron has made 13 ± 6.2 mg/dl, serum ferritin — 38.6 ± 30.9 mg/dl. At 30 % of schoolboys deficiency of iron is determined. Conclusion: In conditions compensated endemic goiter authentic correlation between criteria of an exchange of iron and parameters of iodine maintenance it is not established. Key words: iodine deficience, thyroid, goiter, iron, anemia.

  13. MO-F-CAMPUS-J-01: Effect of Iodine Contrast Agent Concentration On Cerebrovascular Dose for Synchrotron Radiation Microangiography Based On a Simple Mouse Head Model and a Voxel Mouse Head Phantom

    Energy Technology Data Exchange (ETDEWEB)

    Lin, H; Jing, J; Xie, C [Hefei University of Technology, Hefei (China); Lu, Y [Shanghai Jiao Tong University, Shanghai (China)

    2015-06-15

    Purpose: To find effective setting methods to mitigate the irradiation injure in synchrotron radiation microangiography(SRA) by Monte Carlo simulation. Methods: A mouse 1-D head model and a segmented voxel mouse head phantom were simulated by EGSnrc/Dosxyznrc code to investigate the dose enhancement effect of the iodine contrast agent irradiated by a monochromatic synchrotron radiation(SR) source. The influence of, like iodine concentration (IC), vessel width and depth, with and without skull layer protection and the various incident X ray energies, were simulated. The dose enhancement effect and the absolute dose based on the segmented voxel mouse head phantom were evaluated. Results: The dose enhancement ratio depends little on the irradiation depth, but strongly on the IC, which is linearly increases with IC. The skull layer protection cannot be ignored in SRA, the 700µm thick skull could decrease 10% of the dose. The incident X-ray energy can significantly affact the dose. E.g. compared to the dose of 33.2keV for 50mgI/ml, the 32.7keV dose decreases 38%, whereas the dose of 33.7 keV increases 69.2%, and the variation will strengthen more with enhanced IC. The segmented voxel mouse head phantom also showed that the average dose enhancement effect and the maximal voxel dose per photon depends little on the iodine voxel volume ratio, but strongly on IC. Conclusion: To decrease dose damage in SRA, the high-Z contrast agent should be used as little as possible, and try to avoid radiating locally the injected position immediately after the contrast agent injection. The fragile vessel containing iodine should avoid closely irradiating. Avoiding irradiating through the no or thin skull region, or appending thin equivalent material from outside to protect is also a better method. As long as SRA image quality is ensured, using incident X-ray energy as low as possible.

  14. Complex impedance studies of lithium iodine batteries

    Energy Technology Data Exchange (ETDEWEB)

    Schmidt, C.L.; Skarstad, P.M. (Promeon Division Medtronic, Inc. Minneapolis, MN (US))

    1990-08-01

    Complex impedance spectra of conductivity cells containing iodine/poly-2-vinylpyridine cathode material were taken by two- and four-probe techniques. The impedance spectra contain a current-independent bulk resistance in series with a current-dependent interfacial resistance. The current-dependent interfacial resistance has the characteristics expected of a charge-transfer resistance. Moreover, electronically blocked (lithium/lithium iodide) electrodes give the same result as non-blocked (stainless steel) electrodes. This is exactly what would be expected if the medium were an ionic conductor. Complex impedance spectra of lithium/iodine batteries show additional structure, as might be expected, but are consistent with results from the conductivity cells.

  15. A picture of polar iodinated disinfection byproducts in drinking water by (UPLC/)ESI-tqMS.

    Science.gov (United States)

    Ding, Guoyu; Zhang, Xiangru

    2009-12-15

    Iodinated disinfection byproducts (DBPs) are generally more toxic than their chlorinated and brominated analogues. Up to date, only a few iodinated DBPs in drinking water have been identified by gas chromatography/mass spectrometry. In this work, a method for fast selective detection of polar iodinated DBPs was developed using an electrospray ionization-triple quadrupole mass spectrometer (ESI-tqMS) by conducting precursor ion scan of iodide at m/z 126.9. With such a method, pictures of polar iodinated DBPs in chlorinated, chloraminated, and chlorine-ammonia treated water samples were achieved. By coupling state-of-the-art ultra performance liquid chromatography (UPLC) to the ESI-tqMS, structures of 17 iodinated DBPs were tentatively proposed. The results fully demonstrate that, with respect to the DBP number/levels among the three disinfection processes, chloramination generally generated the most/highest iodinated DBPs, chlorination generally produced the fewest/lowest iodinated DBPs, and chlorine-ammonia sequential treatment formed iodinated DBPs lying in between; the numbers of iodinated DBPs in chloraminated Suwannee River Fulvic Acid (SRFA) and Humic Acid (SRHA) were nearly the same, but the levels of aliphatic iodinated DBPs were higher in the chloraminated SRFA while the levels of aromatic iodinated DBPs were higher in the chloraminated SRHA; a couple of nitrogenous iodinated DBPs were found in chloramination and chlorine-ammonia treatment. The ratio of total organic iodine levels in chlorine-ammonia sequential treatment and chloramination could be expressed as a function of the lag time of ammonia addition.

  16. Iodine content of infant formulas and iodine intake of premature babies: high risk of iodine deficiency.

    Science.gov (United States)

    Ares, S; Quero, J; Durán, S; Presas, M J; Herruzo, R; Morreale de Escobar, G

    1994-11-01

    As part of a study of thyroid function in premature babies, the iodine content of their mothers' breast milk, that of 32 formulas from different brands used in Spain, and that of 127 formulas used in other countries was determined. Breast milk contained more iodine--mean (SEM) 10 (1) microgram/dl--than most of the formulas, especially those for premature babies. Iodine intakes were therefore below the recommended daily amount (RDA) for newborns: babies of 27-30 weeks' gestational age took 3.1 (1.1) micrograms/day at 5 days of age and 29.8 (2.7) micrograms by 2 months of age. This problem is not exclusive to Spanish premature babies as the iodine content of many of the formulas on sale in other countries was also inadequate. It is concluded that preterm infants who are formula fed are at high risk of iodine deficiency.

  17. Methods to assess iron and iodine status

    NARCIS (Netherlands)

    Zimmermann, M.B.

    2008-01-01

    Four methods are recommended for assessment of iodine nutrition: urinary iodine concentration, the goitre rate, and blood concentrations of thyroid stimulating hormone and thyroglobulin. These indicators are complementary, in that urinary iodine is a sensitive indicator of recent iodine intake (days

  18. Age-period-cohort models using smoothing splines: a generalized additive model approach.

    Science.gov (United States)

    Jiang, Bei; Carriere, Keumhee C

    2014-02-20

    Age-period-cohort (APC) models are used to analyze temporal trends in disease or mortality rates, dealing with linear dependency among associated effects of age, period, and cohort. However, the nature of sparseness in such data has severely limited the use of APC models. To deal with these practical limitations and issues, we advocate cubic smoothing splines. We show that the methods of estimable functions proposed in the framework of generalized linear models can still be considered to solve the non-identifiability problem when the model fitting is within the framework of generalized additive models with cubic smoothing splines. Through simulation studies, we evaluate the performance of the cubic smoothing splines in terms of the mean squared errors of estimable functions. Our results support the use of cubic smoothing splines for APC modeling with sparse but unaggregated data from a Lexis diagram.

  19. Mandatory fortification of bread with iodised salt modestly improves iodine status in schoolchildren.

    Science.gov (United States)

    Skeaff, Sheila A; Lonsdale-Cooper, Emily

    2013-03-28

    Iodine deficiency has re-emerged in many parts of the world including the UK, Australia and New Zealand (NZ). In 2009, the NZ government introduced the mandatory fortification of bread with iodised salt as a strategy to improve iodine intakes. The aim of the present study was to assess the impact of fortification on the iodine status of NZ schoolchildren. A school-based cluster survey was used to randomly select schools from two NZ cities. Children aged 8-10 years were administered a general questionnaire, and asked to provide a casual urine and finger-prick blood sample. The median urinary iodine concentration (UIC) of the children (n 147) was 113 μg/l, which falls between 100 and 199 μg/l indicating adequate iodine status; 12 % of children had a UIC staple foods, in addition to bread, should be considered to ensure good iodine status in NZ children.

  20. Transferability of regional permafrost disturbance susceptibility modelling using generalized linear and generalized additive models

    Science.gov (United States)

    Rudy, Ashley C. A.; Lamoureux, Scott F.; Treitz, Paul; van Ewijk, Karin Y.

    2016-07-01

    To effectively assess and mitigate risk of permafrost disturbance, disturbance-prone areas can be predicted through the application of susceptibility models. In this study we developed regional susceptibility models for permafrost disturbances using a field disturbance inventory to test the transferability of the model to a broader region in the Canadian High Arctic. Resulting maps of susceptibility were then used to explore the effect of terrain variables on the occurrence of disturbances within this region. To account for a large range of landscape characteristics, the model was calibrated using two locations: Sabine Peninsula, Melville Island, NU, and Fosheim Peninsula, Ellesmere Island, NU. Spatial patterns of disturbance were predicted with a generalized linear model (GLM) and generalized additive model (GAM), each calibrated using disturbed and randomized undisturbed locations from both locations and GIS-derived terrain predictor variables including slope, potential incoming solar radiation, wetness index, topographic position index, elevation, and distance to water. Each model was validated for the Sabine and Fosheim Peninsulas using independent data sets while the transferability of the model to an independent site was assessed at Cape Bounty, Melville Island, NU. The regional GLM and GAM validated well for both calibration sites (Sabine and Fosheim) with the area under the receiver operating curves (AUROC) > 0.79. Both models were applied directly to Cape Bounty without calibration and validated equally with AUROC's of 0.76; however, each model predicted disturbed and undisturbed samples differently. Additionally, the sensitivity of the transferred model was assessed using data sets with different sample sizes. Results indicated that models based on larger sample sizes transferred more consistently and captured the variability within the terrain attributes in the respective study areas. Terrain attributes associated with the initiation of disturbances were

  1. Iodine distribution in the environment as a limiting factor for roe deer antler development.

    Science.gov (United States)

    Lehoczki, Róbert; Erdélyi, Károly; Sonkoly, Krisztina; Szemethy, László; Csányi, Sándor

    2011-02-01

    The iodine-containing hormones produced by the thyroid gland play a role in the complex neuro-hormonal regulation of antler development. The proper function of the thyroid depends on the adequate iodine supply of the organism, which is directly related to the iodine content of food and drinking water. The purpose of this study was to explore the connection between the iodine content of the water base, which has a strong correlation with the iodine concentration of environmental components available to animals, and the antler weight of roe deer (Capreolus capreolus) shot in Hungarian hunting areas. Using a general linear model, controlling for the collective effects of other environmental factors (deer population density, harvest rate, land use, and soil fertility information), the iodine content of the water base explained 51.4% of the total variance of antler weights. The results suggest that antler weights increase with increasing iodine concentration regardless of other factors; thus, the environmental iodine distribution can be a limiting factor suppressing roe deer performance assessed here as antler weight. Further experimental studies of controlled iodine uptake are needed to define the exact physiological iodine requirements of roe deer bucks.

  2. Efficacy and toxicity of iodine disinfection of Atlantic salmon eggs

    Science.gov (United States)

    Chalupnicki, M.A.; Ketola, H.G.; Starliper, C.E.; Gallagher, D.

    2011-01-01

    Recent interest in the restoration of Atlantic salmon Salmo salar in the Great Lakes has given rise to new culture techniques and management programs designed to reduce pathogen transmission while stabilizing and enhancing wild populations. We examined the toxicity of iodine to Atlantic salmon eggs and its effectiveness as a disinfectant against bacteria on egg surfaces. We spawned and fertilized eight gravid Atlantic salmon from Cayuga Lake, New York, and exposed their eggs to 10 concentrations of iodine (5, 10, 50, 75, 100, 500, 750, 1,000, 5,000, and 7,500 mg/L) for 30 min during water hardening. An additional subsample of unfertilized eggs was also exposed to some of the same concentrations of iodine (5, 10, 50, 75, and 100 mg/L) to determine the efficiency of disinfection. Viable eggs were only obtained from four females. Survival of eggs to the eyed stage and hatch tended to be reduced at iodine concentrations of 50 and 75 mg/L and was significantly reduced at concentrations of 100 mg/L iodine or more. We calculated the concentrations of iodine that killed 50% of the Atlantic salmon eggs at eye-up and hatch to be 175 and 85 mg/L, respectively. Aeromonas veronii, A. schubertii, A. hydrophila, A. caviae, Plesiomonas shiggeloides, and Citrobacter spp. were the predominant bacteria present on the surface of green eggs and were significantly reduced by an iodine immersion. The use of iodine as a disinfectant on Atlantic salmon eggs was effective at low concentrations (50–75 mg/L), for which toxicity to Atlantic salmon was minimal.

  3. The story of iodine deficiency: An international challenge in nutrition

    Energy Technology Data Exchange (ETDEWEB)

    Hetzel, B.S.

    1989-01-01

    Iodine deficiency is a risk factor for the growth and development of up to 800 million people living in iodine deficient environments throughout the world. The effects on growth and development, called the iodine deficiency disorders (IDD), comprise goiter, stillbirths and miscarriages, neonatal and juvenile thyroid deficiency, dwarfism, mental defects, deaf mutism, and spastic weakness and paralysis, as well as lesser degrees of loss of physical and mental function. All these effects are due to inadequate thyroid hormone production because iodine is an essential constituent of the thyroid hormone. In the West, IDD has been largely eliminated by the addition of iodine to the diet through iodized salt or through changes in food distribution and technology. IDD still persists in certain areas of Europe where these dietary changes have not occurred. In the Third World, IDD is a major problem in many countries with large populations, such as China, India, Indonesia, Nigeria, and Zaire. In these and other Third World countries, IDD is a significant barrier to social and economic progress which can be removed by correction of the deficiency. This book shows that elimination of iodine deficiency is feasible within the next decade, only requiring a modest financial and technical effort from the West. Part 1 reviews IDD in man and animals. Part 2 discusses the control of iodine deficiency disorders through iodine supplementation, and considers action at the national and international level. Part 3 presents a global review of the status of IDD control. There is a brief conclusion on the way forward to successful control programs.

  4. Iodine intake in Denmark; Jodindtagelse i Danmark

    Energy Technology Data Exchange (ETDEWEB)

    Pedersen, K.M.; Noehr, S.B.; Laurberg, P. [Aalborg Sygehus, Medicinsk Endokrinologisk Afd. og Gynaekologisk/Obstetrisk afd. (Denmark)

    1997-04-01

    Iodine deficiency with a high frequency of goitre and, in severely affected areas, cretinism is common in some areas of the world. In Denmark the iodine intake as evaluated by urinary iodine excretion has been at a stable low level for many years, except for the part of the population now taking iodine supplementation as part of vitamin/mineral preparations. The iodine intake is lowest in the western part to the country where an epidemiological study of elderly subjects has demonstrated a high frequency of goitre and hyperthyroidism in women. This supports the suggestion of a controlled moderate increase in iodine intake via an iodine supplementation program. (au) 40 refs.

  5. Combining an additive and tree-based regression model simultaneously: STIMA

    NARCIS (Netherlands)

    Dusseldorp, E.; Conversano, C.; Os, B.J. van

    2010-01-01

    Additive models and tree-based regression models are two main classes of statistical models used to predict the scores on a continuous response variable. It is known that additive models become very complex in the presence of higher order interaction effects, whereas some tree-based models, such as

  6. Iodine Emissions from Seaweeds: Species-dependent and Seasonal Differences

    Science.gov (United States)

    Adams, Thomas; Ball, Stephen; Leblanc, Catherine; Potin, Philippe

    2015-04-01

    Emissions of iodine from macroalgae into the marine boundary layer (MBL) significantly impact tropospheric chemistry and the biogeochemical cycling of iodine. Gas-phase iodine chemistry perturbs the usual HOx and NOx radical cycles, provides additional sink reactions for tropospheric ozone, and modifies atmospheric oxidizing capacity. Iodine oxides (IxOywith x ≥ 2) formed through the reaction of iodine atoms with ozone nucleate new aerosol particles which, if they grow sufficiently, can act as cloud condensation nuclei (CCN) and so influence the local climate in coastal regions. Some seaweeds, such as brown algae, are important bio-accumulators of iodine. They specifically induce iodine metabolism to protect themselves against oxidative stress, both as a defence mechanism and when exposed to air around low tide. Indeed the dominant emission source of iodine into the atmosphere in coastal regions comes from intertidal macroalgal beds, particularly those of kelp species. We present results from an extensive laboratory study of molecular iodine (I2) emissions from five seaweed species (two Fucales, Ascophyllum nodosum and Fucus vesiculosus, and three kelp species, Laminaria digitata, L. hyperborea and Saccharina latissima). Eighty-four incubation experiments were performed at the Station Biologique in Roscoff (Brittany, France) between September 2012 and June 2013 to quantify species-dependent I2 emission rates in response to progressive air exposure, mimicking low tide, and to investigate any seasonal differences. Measurements were conducted on 'fresh' biological samples: Ascophyllum and Fucus thalli were collected whilst still submerged on an ebbing tide, transported in seawater to the laboratory and analysed immediately; kelp samples were collected by boat, stored in an outside aquarium in running seawater and analysed within a few days. I2 emissions were quantified at high time resolution by broadband cavity enhanced absorption spectrometry (1σ detection limit

  7. Iodine excretion in school children in Copenhagen

    DEFF Research Database (Denmark)

    Rasmussen, Lone B.; Kirkegaard-Klitbo, Ditte Marie; Laurberg, Peter

    2016-01-01

    INTRODUCTION: Studies of dietary habits show a high iodine intake in children in Denmark. Iodine excretion in children has not previously been assessed. Iodine excretion in adults is below the recommended threshold, and it is therefore being discussed to increase the fortification level. The main...... objective of this study was to assess iodine excretion in children living in Copenhagen to establish whether a moderate increase in iodine fortification would lead to excess iodine intake in this group. METHODS: Children in first and fifth grade were recruited through schools in Copenhagen. In total, 244...... children de-ivered a urine sample. Urine samples were analysed for iodine and creatinine, and the results were expressed as urinary iodine concentration (UIC) and as estimated 24-h iodine excretion. Iodine excretion in children was also compared with that of adults living in the same area, investigated...

  8. Iodine deficiency and nutrition in Scandinavia

    DEFF Research Database (Denmark)

    Manousou, Sofia; Dahl, Lisbeth; Heinsbaek Thuesen, Betina

    2017-01-01

    Iodine nutrition is a result of geological conditions, iodine fortification and monitoring strategies within a country together with the dietary habits of the population. This review summarizes the basis for the current iodine situation in the Scandinavian countries in order to identify gaps...... strategies have been used in Scandinavia to improve iodine nutrition. The major source of iodine is iodized salt in Sweden and from milk and dairy products in Norway. In Denmark, drinking water, milk, dairy products and iodized salt used in commercial production of bread are the important sources of iodine....... The current iodine status in Scandinavia is not optimal and action is ongoing to increase iodination in Denmark, where there is mild iodine deficiency in the general population. Data from all three countries indicate insufficient iodine nutrition during pregnancy and there is a need for data from children...

  9. Iodinated Meroditerpenes from a Red Alga Callophycus sp.

    Science.gov (United States)

    Lavoie, Serge; Brumley, David; Alexander, Troy S; Jasmin, Christine; Carranza, Franz A; Nelson, Kate; Quave, Cassandra L; Kubanek, Julia

    2017-04-21

    Unique iodine-containing meroditerpenes iodocallophycoic acid A (1) and iodocallophycols A-D (2-5) were discovered from the Fijian red alga Callophycus sp. Because flexibility of the molecular skeleton impaired full characterization of relative stereochemistries by NMR spectroscopy, a DFT-based theoretical model was developed to derive relevant interproton distances which were compared to those calculated from NOE measurements, yielding the relative stereochemistries. The correct 2S,6S,7S,10S,14S enantiomers were then identified by comparison of theoretical and experimental ECD spectra. Biological activities of these iodinated and brominated meroditerpenes and additional new, related bromophycoic acid F (6) and bromophycoic acid A methyl ester (7), were evaluated for relevant human disease targets. Iodocallophycoic acid A (1) showed moderate antibiotic activity against methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococcus faecium (VREF) with MIC values of 1.4 and 2.2 μg mL(-1), respectively. It also potentiated the anti-MRSA activity of oxacillin in a synergistic fashion, resulting in an 8-fold increase in oxacillin potency, for a MIC of 16 μg mL(-1).

  10. Iodine supplementation for women during the preconception, pregnancy and postpartum period.

    Science.gov (United States)

    Harding, Kimberly B; Peña-Rosas, Juan Pablo; Webster, Angela C; Yap, Constance My; Payne, Brian A; Ota, Erika; De-Regil, Luz Maria

    2017-03-05

    Iodine is an essential nutrient required for the biosynthesis of thyroid hormones, which are responsible for regulating growth, development and metabolism. Iodine requirements increase substantially during pregnancy and breastfeeding. If requirements are not met during these periods, the production of thyroid hormones may decrease and be inadequate for maternal, fetal and infant needs. The provision of iodine supplements may help meet the increased iodine needs during pregnancy and the postpartum period and prevent or correct iodine deficiency and its consequences. To assess the benefits and harms of supplementation with iodine, alone or in combination with other vitamins and minerals, for women in the preconceptional, pregnancy or postpartum period on their and their children's outcomes. We searched Cochrane Pregnancy and Childbirth's Trials Register (14 November 2016), and the WHO International Clinical Trials Registry Platform (ICTRP) (17 November 2016), contacted experts in the field and searched the reference lists of retrieved studies and other relevant papers. Randomized and quasi-randomized controlled trials with randomisation at either the individual or cluster level comparing injected or oral iodine supplementation (such as tablets, capsules, drops) during preconception, pregnancy or the postpartum period irrespective of iodine compound, dose, frequency or duration. Two review authors independently assessed trial eligibility, risk of bias, extracted data and conducted checks for accuracy. We used the GRADE approach to assess the quality of the evidence for primary outcomes.We anticipated high heterogeneity among trials, and we pooled trial results using random-effects models and were cautious in our interpretation of the pooled results. We included 14 studies and excluded 48 studies. We identified five ongoing or unpublished studies and two studies are awaiting classification. Eleven trials involving over 2700 women contributed data for the comparisons in

  11. Evolution of iodine deficiency disorders control program in India: A journey of 5,000 years

    OpenAIRE

    Chandrakant S Pandav

    2013-01-01

    Iodine deficiency disorders (IDD) has been documented since around 5,000 years. However, geological factors like frequent glaciations, flooding, and changing of course of rivers has led to iodine deficiency in soil. As a result everyone remains at risk of IDD, if optimum intake of iodine is not sustained. Evolution of the IDD control program in India has been a dynamic process. The model of IDD control program in India provides important lessons for successful implementation of a national hea...

  12. Permeation of iodide from iodine-enriched yeast through porcine intestine.

    Science.gov (United States)

    Ryszka, Florian; Dolińska, Barbara; Zieliński, Michał; Chyra, Dagmara; Dobrzański, Zbigniew

    2013-01-01

    Iodine deficiency is a common phenomenon, threatening the whole global human population. Recommended daily intake of iodine is 150 μg for adults and 250 μg for pregnant and breastfeeding women. About 50% of human population can be at risk of moderate iodine deficiency. Due to this fact, increased iodine supplementation is recommended, through intake of iodized mineral water and salt iodization. The aim of this study was to investigate permeation and absorption of iodide from iodine bioplex (experimental group) in comparison with potassium iodide (controls). Permeation and absorption processes were investigated in vitro using a porcine intestine. The experimental model was based on a standard Franz diffusion cell (FD-Cell). The iodine bioplex was produced using Saccharomyces cerevisiae yeast and whey powder: iodine content - 388 μg/g, total protein - 28.5%, total fat - 0.9%., glutamic acid - 41.2%, asparaginic acid - 29.4%, lysine - 24.8%; purchased from: F.Z.N.P. Biochefa, Sosnowiec, Poland. Potassium iodide was used as controls, at 388 μg iodine concentration, which was the same as in iodine-enriched yeast bioplex. A statistically significant increase in iodide permeation was observed for iodine-enriched yeast bioplex in comparison with controls - potassium iodide. After 5h the total amount of permeated iodide from iodine-enriched yeast bioplex was 85%, which is ~ 2-fold higher than controls - 37%. Iodide absorption was by contrast statistically significantly higher in controls - 7.3%, in comparison with 4.5% in experimental group with iodine-enriched yeast bioplex. Presented results show that iodide permeation process dominates over absorption in case of iodine-enriched yeast bioplex.

  13. Multivariable model development and internal validation for prostate cancer specific survival and overall survival after whole-gland salvage Iodine-125 prostate brachytherapy

    NARCIS (Netherlands)

    Peters, Max; van der Voort van Zyp, Jochem R N; Moerland, Marinus A; Hoekstra, Carel J; van de Pol, Sandrine; Westendorp, Hendrik; Maenhout, Metha; Kattevilder, Rob; Verkooijen, Helena M; van Rossum, Peter S N; Ahmed, Hashim U; Shah, Taimur T; Emberton, Mark; van Vulpen, Marco

    2016-01-01

    BACKGROUND: Whole-gland salvage Iodine-125-brachytherapy is a potentially curative treatment strategy for localised prostate cancer (PCa) recurrences after radiotherapy. Prognostic factors influencing PCa-specific and overall survival (PCaSS & OS) are not known. The objective of this study was to de

  14. Iodine nutritional status in pregnant women of two historically different iodine-deficient areas of Catalonia, Spain.

    Science.gov (United States)

    Vila, Lluis; Serra-Prat, Mateu; de Castro, Alfonso; Palomera, Elisabet; Casamitjana, Roser; Legaz, Gustavo; Barrionuevo, Celia; Muñoz, José A; García, Ana J; Lal-Trehan, Sanjay; García, Amparo; Durán, Josep; Puig-Domingo, Manel

    2011-10-01

    Catalonia (Spain) has a historically worse situation of mild iodine deficiency in the Pyrenees Mountains compared with the coastal region. The aim of this study was to evaluate the current iodine status in pregnant women living in these two areas. An epidemiologic prospective survey included 267 consecutive pregnancies in the Catalan mountains (n = 139) and coast (n = 128) studied during the first trimester; an additional subset of 135 women from the initial cohort was available for evaluation in the third trimester. Urinary iodine (UI) was measured, and questionnaires to determine iodized salt and sea fish consumption and potassium iodide supplementation were administered. The median UI in the first trimester was 163 μg/L for the entire cohort, with differences between mountain and coastal regions (209 versus 142 μg/L, P = 0.007). The highest prevalence of iodized salt consumption was in the mountain area (58% versus 36.4%, P pregnancy (190 versus 154 μg/L, P = 0.015). A reversal in the historically iodine-deficient situation was observed in the Catalan Pyrenees compared with the coastal area, with a globally acceptable iodine status in pregnant women of the two geographic locations. Iodized salt consumption seems to have contributed to maintaining an acceptable iodine status in this population. Copyright © 2011 Elsevier Inc. All rights reserved.

  15. Radiochemistry of iodine

    Energy Technology Data Exchange (ETDEWEB)

    Kahn, M.; Kleinberg, J.

    1977-09-01

    The preparation of isotopes of the element, with selected procedures for its determination in or separation from various media is described along with the separating of iodine species from each other. Each part of the introductory section is referenced separately from the remainder of the monograph. For the preparative and analytical sections there is an extensive, indexed bibliography which was developed from the indexes of Volumes 19 to 30 inclusive (1965-1974) of Nuclear Science Abstracts (NSA). From these indexes the NSA abstracts of possible pertinent references were selected for examination and a choice was made of those references which were to be included in the bibliography. The bibliography has both primary and secondary references. Although the monograph does not cover hot atom chemistry, the kinetics of exchange reactions, decay schemes, or physiological applications, papers in these areas were examined as possible sources of useful preparative and analytical procedures. (JRD)

  16. Modeling the cardiovascular system using a nonlinear additive autoregressive model with exogenous input

    Science.gov (United States)

    Riedl, M.; Suhrbier, A.; Malberg, H.; Penzel, T.; Bretthauer, G.; Kurths, J.; Wessel, N.

    2008-07-01

    The parameters of heart rate variability and blood pressure variability have proved to be useful analytical tools in cardiovascular physics and medicine. Model-based analysis of these variabilities additionally leads to new prognostic information about mechanisms behind regulations in the cardiovascular system. In this paper, we analyze the complex interaction between heart rate, systolic blood pressure, and respiration by nonparametric fitted nonlinear additive autoregressive models with external inputs. Therefore, we consider measurements of healthy persons and patients suffering from obstructive sleep apnea syndrome (OSAS), with and without hypertension. It is shown that the proposed nonlinear models are capable of describing short-term fluctuations in heart rate as well as systolic blood pressure significantly better than similar linear ones, which confirms the assumption of nonlinear controlled heart rate and blood pressure. Furthermore, the comparison of the nonlinear and linear approaches reveals that the heart rate and blood pressure variability in healthy subjects is caused by a higher level of noise as well as nonlinearity than in patients suffering from OSAS. The residue analysis points at a further source of heart rate and blood pressure variability in healthy subjects, in addition to heart rate, systolic blood pressure, and respiration. Comparison of the nonlinear models within and among the different groups of subjects suggests the ability to discriminate the cohorts that could lead to a stratification of hypertension risk in OSAS patients.

  17. Adequate Iodine Status in New Zealand School Children Post-Fortification of Bread with Iodised Salt

    Science.gov (United States)

    Jones, Emma; McLean, Rachael; Davies, Briar; Hawkins, Rochelle; Meiklejohn, Eva; Ma, Zheng Feei; Skeaff, Sheila

    2016-01-01

    Iodine deficiency re-emerged in New Zealand in the 1990s, prompting the mandatory fortification of bread with iodised salt from 2009. This study aimed to determine the iodine status of New Zealand children when the fortification of bread was well established. A cross-sectional survey of children aged 8–10 years was conducted in the cities of Auckland and Christchurch, New Zealand, from March to May 2015. Children provided a spot urine sample for the determination of urinary iodine concentration (UIC), a fingerpick blood sample for Thyroglobulin (Tg) concentration, and completed a questionnaire ascertaining socio-demographic information that also included an iodine-specific food frequency questionnaire (FFQ). The FFQ was used to estimate iodine intake from all main food sources including bread and iodised salt. The median UIC for all children (n = 415) was 116 μg/L (females 106 μg/L, males 131 μg/L) indicative of adequate iodine status according to the World Health Organisation (WHO, i.e., median UIC of 100–199 μg/L). The median Tg concentration was 8.7 μg/L, which was <10 μg/L confirming adequate iodine status. There was a significant difference in UIC by sex (p = 0.001) and ethnicity (p = 0.006). The mean iodine intake from the food-only model was 65 μg/day. Bread contributed 51% of total iodine intake in the food-only model, providing a mean iodine intake of 35 μg/day. The mean iodine intake from the food-plus-iodised salt model was 101 μg/day. In conclusion, the results of this study confirm that the iodine status in New Zealand school children is now adequate. PMID:27196925

  18. Adequate Iodine Status in New Zealand School Children Post-Fortification of Bread with Iodised Salt

    Directory of Open Access Journals (Sweden)

    Emma Jones

    2016-05-01

    Full Text Available Iodine deficiency re-emerged in New Zealand in the 1990s, prompting the mandatory fortification of bread with iodised salt from 2009. This study aimed to determine the iodine status of New Zealand children when the fortification of bread was well established. A cross-sectional survey of children aged 8–10 years was conducted in the cities of Auckland and Christchurch, New Zealand, from March to May 2015. Children provided a spot urine sample for the determination of urinary iodine concentration (UIC, a fingerpick blood sample for Thyroglobulin (Tg concentration, and completed a questionnaire ascertaining socio-demographic information that also included an iodine-specific food frequency questionnaire (FFQ. The FFQ was used to estimate iodine intake from all main food sources including bread and iodised salt. The median UIC for all children (n = 415 was 116 μg/L (females 106 μg/L, males 131 μg/L indicative of adequate iodine status according to the World Health Organisation (WHO, i.e., median UIC of 100–199 μg/L. The median Tg concentration was 8.7 μg/L, which was <10 μg/L confirming adequate iodine status. There was a significant difference in UIC by sex (p = 0.001 and ethnicity (p = 0.006. The mean iodine intake from the food-only model was 65 μg/day. Bread contributed 51% of total iodine intake in the food-only model, providing a mean iodine intake of 35 μg/day. The mean iodine intake from the food-plus-iodised salt model was 101 μg/day. In conclusion, the results of this study confirm that the iodine status in New Zealand school children is now adequate.

  19. Iodine-paint interactions during a core fusion accident; Les interactions iode-peinture au cours d'un accident de fusion du coeur

    Energy Technology Data Exchange (ETDEWEB)

    Simondi-Teisseire, B. [Institut de Radioprotection et de Surete Nucleaire, Service d' etude et de recherche experimentale sur la chimie, 13 - Cadarache (France); Cantrel, L. [Institut de Radioprotection et de Surete Nucleaire, Laboratoire d' Etudes du corium et du Transfert de Radioelements, 13 - Cadarache (France); Fillet, S. [Institut de Radioprotection et de Surete Nucleaire, Laboratoire d' Experimentation environnement et chimie, 13 - Cadarache (France)

    2011-01-15

    If a core fusion accident should occur, radioactive iodine would be released from the fuel and would reach the reactor containment building, and then react with wall paintings to form organic iodine compounds, i.e. volatile compounds which are difficult to filtrate and therefore would be released in the environment. This article briefly reports investigations of the formation/destruction mechanisms of these volatile iodine compounds, notably through the Epicur program. This program focused on two prevailing phenomena: the radiolytic oxidation of iodine present in sump water, and the production of volatile organic iodides from painted surfaces where iodine adsorption occurs. Iodine behaviour is modelled by using the Astec code

  20. Thyroidectomy: is Lugol's iodine necessary?

    OpenAIRE

    Holl-Allen, R T J

    1983-01-01

    In a randomised controlled clinical trial of Lugol's iodine against placebo in 44 patients undergoing thyroidectomy we have failed to show any benefit in terms of reduced bleeding or operative facility after using iodide solution.

  1. Thyroidectomy: is Lugol's iodine necessary?

    Science.gov (United States)

    Coyle, P J; Mitchell, J E

    1982-09-01

    In a randomised controlled clinical trial of Lugol's iodine against placebo in 44 patients undergoing thyroidectomy we have failed to show any benefit in terms of reduced bleeding or operative facility after using iodide solution.

  2. A general additive-multiplicative rates model for recurrent event data

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    In this article, we propose a general additive-multiplicative rates model for recurrent event data. The proposed model includes the additive rates and multiplicative rates models as special cases. For the inference on the model parameters, estimating equation approaches are developed, and asymptotic properties of the proposed estimators are established through modern empirical process theory. In addition, an illustration with multiple-infection data from a clinic study on chronic granulomatous disease is provided.

  3. Validation analysis of probabilistic models of dietary exposure to food additives.

    Science.gov (United States)

    Gilsenan, M B; Thompson, R L; Lambe, J; Gibney, M J

    2003-10-01

    The validity of a range of simple conceptual models designed specifically for the estimation of food additive intakes using probabilistic analysis was assessed. Modelled intake estimates that fell below traditional conservative point estimates of intake and above 'true' additive intakes (calculated from a reference database at brand level) were considered to be in a valid region. Models were developed for 10 food additives by combining food intake data, the probability of an additive being present in a food group and additive concentration data. Food intake and additive concentration data were entered as raw data or as a lognormal distribution, and the probability of an additive being present was entered based on the per cent brands or the per cent eating occasions within a food group that contained an additive. Since the three model components assumed two possible modes of input, the validity of eight (2(3)) model combinations was assessed. All model inputs were derived from the reference database. An iterative approach was employed in which the validity of individual model components was assessed first, followed by validation of full conceptual models. While the distribution of intake estimates from models fell below conservative intakes, which assume that the additive is present at maximum permitted levels (MPLs) in all foods in which it is permitted, intake estimates were not consistently above 'true' intakes. These analyses indicate the need for more complex models for the estimation of food additive intakes using probabilistic analysis. Such models should incorporate information on market share and/or brand loyalty.

  4. [Iodine deficiency in cardiovascular diseases].

    Science.gov (United States)

    Molnár, I; Magyari, M; Stief, L

    1998-08-30

    The thyroid hormone deficiency on cardiovascular function can be characterized with decreased myocardial contractility and increased peripheral vascular resistance as well as with the changes in lipid metabolism. 42 patients with cardiovascular disease (mean age 65 +/- 13 yr, 16 males) were investigated if iodine insufficiency can play a role as a risk factor for the cardiovascular diseases. The patients were divided in 5 subgroups on the ground of the presence of hypertension, congestive heart failure, cardiomyopathy, coronary disfunction and arrhythmia. Urine iodine concentration (5.29 +/- 4.52 micrograms/dl) was detected with Sandell-Kolthoff colorimetric reaction. The most decreased urine iodine concentration was detected in the subgroups with arrhythmia and congestive heart failure (4.7 +/- 4.94 micrograms/dl and 4.9 +/- 4.81 micrograms/dl, respectively). An elevated TSH level was found by 3 patients (5.3 +/- 1.4 mlU/l). An elevation in lipid metabolism (cholesterol, triglyceride) associated with all subgroups without arrhythmia. In conclusion, the occurrence of iodine deficiency in cardiovascular disease is frequent. Iodine supplementation might prevent the worsing effect of iodine deficiency on cardiovascular disease.

  5. Studies in iodine metabolism: Progress report, July 1968-July 1969

    Energy Technology Data Exchange (ETDEWEB)

    Van Middlesworth, L.

    1987-01-01

    This document describes research on iodine metabolism conducted at the University of Tennessee, Memphis between July 1968 and July 1969. The author and his research team prepared autoradiographs of rat thyroids from individuals exposed to Iodine 125 in utero. Additional studies were conducted to determine the effect on hypothalamic lesions on iodide metabolism in rats; to evaluate an iodide-specific electrode for measuring iodide levels in blood or urine; and to study the amount of thyroxine absorption from the intestine. An analysis of bovine and sheep thyroids from eight locations provided additional information on global fallout levels. 21 figs., 2 tabs.

  6. Migration behaviour of iodine in nuclear fuel

    Energy Technology Data Exchange (ETDEWEB)

    Hocking, W.H.; Verrall, R.A.; Muir, I.J

    2001-07-01

    A novel out-reactor method has been further developed for investigating the migration behaviour of fission products in UO{sub 2} nuclear fuel, which allows the effects of thermal diffusion. radiation damage and local segregation to be independently assessed. Tailored concentration profiles of any desired species are first created in the near-surface region of polished samples by ion implantation. The impact of either thermal annealing or simulated fission is then precisely determined by depth profiling with high-performance secondary ion mass spectrometry (SIMS). Comparison of iodine migration in U0{sub 2} wafers that had been ion-implanted to fluences spanning five orders of magnitude has revealed subtle radiation-damage effects and a pronounced concentration dependence for thermal diffusion. At concentrations above {approx}10{sup 16} atoms/cm{sup 3} much of the iodine became trapped, likely in microscopic bubbles. True thermal diffusion coefficients for iodine in polycrystalline U0{sub 2} have been derived by modelling the low-fluence data. (author)

  7. Iodine status in neonates in Denmark

    DEFF Research Database (Denmark)

    Nøhr, S B; Laurberg, Peter; Børlum, K G

    1994-01-01

    Iodine status of 147 neonates born in five different regions of Denmark was evaluated in relation to the iodine content of breast milk and iodine supplementation taken by the mother. Approximately two-thirds of the women had not received iodine supplementation. They had low iodine concentrations...... in breast milk and urinary iodine concentrations of the neonates at day 5 were low. The median values (milk/urine) were 33.6/31.7 micrograms/l (Randers 22/26, Ringkøbing 29/16, Aalborg 36/31. Arhus 54/41 and Copenhagen 55/59 micrograms/l). Higher values were found in the group where tablets containing...... iodine had been taken (milk/urine: 57.0/61.0 micrograms/l). In general, the values are low compared with internationally recommended levels. We suggest that mothers without autoimmune thyroid disease should receive iodine supplementation in the form of vitamin/mineral tablets containing iodine (150...

  8. Three-dimensional patterns in the Lengyel-Rabai-Epstein model of the chlorine dioxide-iodine-malonic acid reaction

    Science.gov (United States)

    Moore, Peter K.; Horsthemke, Werner

    2009-12-01

    We present computational solutions to the Lengyel-Rabai-Epstein model in three space dimensions. The results show that three-dimensional patterns exist and that they differ significantly from the two-dimensional patterns. Patterns occur at three locations in the reactor corresponding to peaks in the one-dimensional concentration of the starch tri-iodide concentration. Each pattern possesses its own intrinsic wavelength and is neither striped nor hexagonal, the two types that have been shown to exist in two dimensions. Computations suggest a bifurcation exists as a function of the reactor thickness. Solutions are computed using a high-order adaptive finite element method coupled with a multistep integrator in time. Linear systems generated in the multistep solver are solved using the iterative method GMRES with a Jacobi preconditioner. Matrix storage is reduced by incomplete assembly via thresholding. Preconditioner factorization and matrix-vector multiplication efficiency are enhanced by the use of OPENMP.

  9. Iodine emissions from the sea ice of the Weddell Sea

    Directory of Open Access Journals (Sweden)

    H. M. Atkinson

    2012-05-01

    Full Text Available Iodine compounds were measured above, below and within the sea ice of the Weddell Sea during a cruise in 2009, to elucidate the mechanism of local enhancement and volatilisation of iodine. I2 mixing ratios of up to 12.4 pptv were measured 10 m above the sea ice, and up to 31 pptv was observed above surface snow on the nearby Brunt Ice Shelf – large amounts. Atmospheric IO of up to 7 pptv was measured from the ship, and the average sum of HOI and ICl was 1.9 pptv. These measurements confirm the Weddell Sea as an iodine hotspot. Average atmospheric concentrations of CH3I, C2H5I, CH2ICl, 2-C3H7I, CH2IBr and 1-C3H7I were each 0.2 pptv or less. On the Brunt Ice Shelf, enhanced concentrations of CH3I and C2H5I (up to 0.5 and 1 pptv, respectively were observed in firn air, with a diurnal profile that suggests the snow may be a source. In the sea ice brine, iodocarbons concentrations were over 10 times those of the sea water below. The sum of iodide + iodate was depleted in sea ice samples, suggesting some missing iodine chemistry. Flux calculations suggest I2 dominates the iodine atom flux to the atmosphere, but models cannot reconcile the observations and suggest either a missing iodine source or other deficiencies in our understanding of iodine chemistry. The observation of new particle formation, consistent with the model predictions, strongly suggests an iodine source. This combined study of iodine compounds is the first of its kind in this unique region of sea ice rich in biology and rich in iodine chemistry.

  10. Iodine emissions from the sea ice of the Weddell Sea

    Directory of Open Access Journals (Sweden)

    H. M. Atkinson

    2012-11-01

    Full Text Available Iodine compounds were measured above, below and within the sea ice of the Weddell Sea during a cruise in 2009, to make progress in elucidating the mechanism of local enhancement and volatilisation of iodine. I2 mixing ratios of up to 12.4 pptv were measured 10 m above the sea ice, and up to 31 pptv was observed above surface snow on the nearby Brunt Ice Shelf – large amounts. Atmospheric IO of up to 7 pptv was measured from the ship, and the average sum of HOI and ICl was 1.9 pptv. These measurements confirm the Weddell Sea as an iodine hotspot. Average atmospheric concentrations of CH3I, C2H5I, CH2ICl, 2-C3H7I, CH2IBr and 1-C3H7I were each 0.2 pptv or less. On the Brunt Ice Shelf, enhanced concentrations of CH3I and C2H5I (up to 0.5 and 1 pptv respectively were observed in firn air, with a diurnal profile that suggests the snow may be a source. In the sea ice brine, iodocarbons concentrations were over 10 times those of the sea water below. The sum of iodide + iodate was depleted in sea ice samples, suggesting some missing iodine chemistry. Flux calculations suggest I2 dominates the iodine atom flux to the atmosphere, but models cannot reconcile the observations and suggest either a missing iodine source or other deficiencies in our understanding of iodine chemistry. The observation of new particle formation, consistent with the model predictions, strongly suggests an iodine source. This combined study of iodine compounds is the first of its kind in this unique region of sea ice rich in biology and rich in iodine chemistry.

  11. Transport of Iodine Species in the Terrestrial Environment

    Science.gov (United States)

    Hu, Q.; Moran, J.; Zhao, P.

    2003-12-01

    The fate and transport of iodine in the environment is of interest because of the large production and release of 129I from anthropogenic sources. 129I has a long half-life (1.57 x 107 years) and exhibits complex geochemical behavior. The main source of 129I in the environment is from nuclear fuel reprocessing facilities; about 2,600 kg from facilities in England and France. During 1944-1972, the Hanford Site in Washington state released about 260 kg 129I. Iodine has a unique and complex chemistry in the environment, and its fate and transport in aqueous environments is dictated by its chemical speciation. In reducing environments, aqueous iodine usually occurs as the highly mobile iodide anion (I-). Under more oxidizing conditions, iodine may be present as the more reactive iodate anion (IO3-), which could lead to retarded transport through interaction with clays and organic matter. Co-existing iodine species (I-, IO3-, I2, and organoiodine compounds), in different proportions, has been reported in various terrestrial environments. However, there are conflicting reports regarding the environmental behavior of the different types of inorganic iodine and few publications on organic iodine compounds. This work examines the sorption and transport behavior of both inorganic and organic iodine species in geological samples from several complexes of the U.S. Department of Energy, where transport of radionuclides, including 129I, may occur. Experiments on soils and sediments from the Savannah River Site in South Carolina, Oak Ridge Site in Tennessee, Hanford Site in Washington, Livermore Site 300 in California, and a surface soil from Santa Fe in New Mexico near Los Alamos were carried out. Samples from Savannah River Site and Livermore Site 300 are available from different depths. In addition, a surface soil of Wisconsin with a high amount of organic matter is utilized. This wide variety of sample types provides opportunities to examine the influence of organic matter

  12. Indirect lymph node lymphangiography using an iodine-based contrast medium and projection radiography following submucosal injection in a rabbit model.

    Science.gov (United States)

    Dietrich, A; Wuttke, M; Walter, F; De Leon, I; Kloeppel, R; Schoenfelder, M

    2002-11-01

    This study investigated the possibility of local lymph node detection and lymphatic mapping following submucosal injection of an iodine-based contrast medium. We established a contrast medium (oil/water emulsion on iodine basis) with a particle size of mainly 1.7+/-0.1 micro m. Ten rabbits received rectal submucosal injections of the contrast medium and underwent repeated projection radiography. Passage of the contrast medium into lymphatic vessels and storage in lymph nodes was seen in all ten animals. The best contrast was achieved within 24 and 48 h after injection. Lymph nodes were still seen in eight cases with the final radiograph on day 14. There were no clinical side effects observed. Injection sites showed mild signs of inflammation in histological examinations. Pathological signs were not detectable in lymph nodes containing the contrast media. This method appears useful when investigating local lymph nodes following submucosal injection due to its passage into lymphatic vessels and storage in lymph nodes.

  13. Monitoring the severity of iodine deficiency disorders in Uganda ...

    African Journals Online (AJOL)

    Conclusion : USI has improved iodine intake in Uganda. ... have low iodine consumption, while others such as Luwero now have iodine excess. ... Recommendation : The national set standard of household salt iodine of 100ppm be revised.

  14. Iodine Excess is a Risk Factor for Goiter Formation

    African Journals Online (AJOL)

    mandatory iodine fortification of salt, goiter rates reduced to 14% ... studies have suggested that excess iodine may be the cause of ... change, which depends upon the amount of iodine present .... medicine with too much iodine causes thyroid.

  15. Iodine Concentration in Breastmilk and Urine among Lactating Women of Bhaktapur, Nepal

    Directory of Open Access Journals (Sweden)

    Sigrun Henjum

    2016-04-01

    Full Text Available Adequate iodine concentration in breastmilk (BMIC is essential for optimal neonatal thyroid hormone synthesis and neurological development in breastfed infants. For many decades, iodine deficiency has been a public health problem in Nepal. However, recently, excessive iodine intakes among Nepali infants have been reported. This study aimed to measure BMIC and urinary iodine concentration (UIC among lactating women in a peri-urban area of Nepal. Iodine concentration was measured in spot urine (n = 485 and breastmilk samples (n = 291 of 500 randomly selected lactating women. The median (p25, p75 BMIC and median UIC were 250 (130, 370 µg/L and 230 (135–377 µg/L, respectively. Around 82% had BMIC > 100 µg/L, 61% had BMIC > 200 µg/L and 81% had UIC > 100 µg/L, 37% had >300 µg/L and 20% had >500 µg/L. In multiple linear regression models, time since birth (β 3.0, 95% CI (0.2, 5.0 and UIC (β 1.0, 95% CI (0.1, 2.0 were associated with BMIC, explaining 26% of the variance. A large proportion of the women had adequate BMIC and UIC; however, a subset had high iodine concentrations. These findings emphasize the importance of carefully monitoring iodine intake to minimize the risk of iodine excess and subsequently preventing transient iodine-induced hypothyroidism in breastfed infants.

  16. Efforts to Consolidate Chalcogels with Adsorbed Iodine

    Energy Technology Data Exchange (ETDEWEB)

    Riley, Brian J.; Pierce, David A.; Chun, Jaehun

    2013-08-28

    This document discusses ongoing work with non-oxide aerogels, called chalcogels, that are under development at the Pacific Northwest National Laboratory as sorbents for gaseous iodine. Work was conducted in fiscal year 2012 to demonstrate the feasibility of converting Sn2S3 chalcogel without iodine into a glass. This current document summarizes the work conducted in fiscal year 2013 to assess the consolidation potential of non-oxide aerogels with adsorbed iodine. The Sn2S3 and Sb13.5Sn5S20 chalcogels were selected for study. The first step in the process for these experiments was to load them with iodine (I2). The I2 uptake was ~68 mass% for Sn2S3 and ~50 mass% for Sb13.5Sn5S20 chalcogels. X-ray diffraction (XRD) of both sets of sorbents showed that metal-iodide complexes were formed during adsorption, i.e., SnI4 for Sn2S3 and SbI3 for Sb13.5Sn5S20. Additionally, metal-sulfide-iodide complexes were formed, i.e., SnSI for Sn2S3 and SbSI for Sb13.5Sn5S20. No XRD evidence for unreacted iodine was found in any of these samples. Once the chalcogels had reached maximum adsorption, the consolidation potential was assessed. Here, the sorbents were heated for consolidation in vacuum-sealed quartz vessels. The Sb13.5Sn5S20 chalcogel was heated both (1) in a glassy carbon crucible within a fused quartz tube and (2) in a single-containment fused quartz tube. The Sn2S3 chalcogel was only heated in a single-containment fused quartz tube. In both cases with the single-containment fused quartz experiments, the material consolidated nicely. However, in both cases, there were small fractions of metal iodides not incorporated into the final product as well as fused quartz particles within the melt due to the sample attacking the quartz wall during the heat treatment. The Sb13.5Sn5S20 did not appear to attack the glassy carbon crucible so, for future experiments, it would be ideal to apply a coating, such as pyrolytic graphite, to the inner walls of the fused quartz vessel to prevent

  17. Technical Evaluation of Biogeochemical Transformation of Iodine at 200-UP-1, Hanford, WA

    Science.gov (United States)

    Lee, M. H.; Cordova, E.; Brooks, S.; Moser, E.; Wells, J.; Lee, B.

    2015-12-01

    From the 1940s through the early 1990s, liquid wastes from materials used and produced at the Hanford Site were disposed to the ground through cribs, ditches, ponds, and trenches. Primary groundwater and vadose zone contaminants include carbon tetrachloride, uranium, nitrate, chromium, 129I, 99Tc, and tritium. Iodine-129 is of environmental concern due to its long half-life, mobility, and hazardous potential to humans through bioaccumulation, and is one of the primary risk drivers for the Hanford site. The 200 West area of the Hanford Site contains two separate plumes covering 1,500 acres where 129I concentrations are ~3.5 pCi/L in Hanford groundwater. Speciation analysis shows that iodate comprises 70.6% of the iodine present, and organo-iodide and iodide comprise 25.8% and 3.6% respectively. While hydraulic containment is the currently selected remedy for 129I in the groundwater, there is currently no remedy selected for controlling migration of 129I from the vadose zone to the groundwater. Research is currently underway to develop a site conceptual model for understanding the biogeochemical drivers for iodine speciation and determine the processes that drive the fate and transport of 129I through the vadose zone and into groundwater. These data will provide the information to decrease the uncertainty related to the inventory, distribution, and transport properties which will lead to appropriate treatment strategies for the 129I plume(s). Understanding the mechanisms and contributors to iodine speciation is important in order to develop bioremediation strategies for contaminated areas. The effect that microbial communities and humic acid have on iodine speciation and sorption was explored using Ringold sediment from the 200 West Area exposed to varying levels of 129I contamination in conjunction with varying growth media constituents. Several isolates obtained from these batch studies have been shown to reduce over 80% of iodate present in growth media when

  18. A class of additive-accelerated means regression models for recurrent event data

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    In this article, we propose a class of additive-accelerated means regression models for analyzing recurrent event data. The class includes the proportional means model, the additive rates model, the accelerated failure time model, the accelerated rates model and the additive-accelerated rate model as special cases. The new model offers great flexibility in formulating the effects of covariates on the mean functions of counting processes while leaving the stochastic structure completely unspecified. For the inference on the model parameters, estimating equation approaches are derived and asymptotic properties of the proposed estimators are established. In addition, a technique is provided for model checking. The finite-sample behavior of the proposed methods is examined through Monte Carlo simulation studies, and an application to a bladder cancer study is illustrated.

  19. Multiple High-Fidelity Modeling Tools for Metal Additive Manufacturing Process Development Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Despite the rapid commercialization of additive manufacturing technology such as selective laser melting, SLM, there are gaps in process modeling and material...

  20. Effect of processing on iodine content of some selected plants food

    African Journals Online (AJOL)

    STORAGESEVER

    2010-02-22

    Feb 22, 2010 ... the wide range of effects low iodine status can have on health. ... other portions were mixed together and used for cassava flour. (lafun). The last .... Extension of thermal requirement to 30 min resulted in an ... Kontras DA, Matovinovic J, Vought R (2002). The ecology of iodine In: ... disease in animal models.

  1. Integrated intervention model and effects of iodine deficiency disease in Yixian of Baoding city%保定市易县持续消除碘缺乏病的综合干预模式及效果

    Institute of Scientific and Technical Information of China (English)

    张进国

    2012-01-01

      Objective To explore the intervention model of sustainable elimination iodine deficiency disorders. Methods Integrated intervention measures: Government attaches importance to, Universal salt iodization, Sectoral collaboration, The creation of iodine deficiency disorders clinic, Priority interventions, advocacy and education etc. And evaluate the effects of intervention. Results The goiter prevalence of the children in Yixian has been controlled for 14 years within 5%from 1998 to 2011;Qualified iodized salt coverage rate was more than 90 percent from 1996 to 2011;Children's urinary iodine median was more than 100μg/L from 1995 to 2011. conclusion The results of this study show that the integrated intervention model and its method are effective ways to achieve sustainable elimination of iodine deficiency disorders%  目的探讨可持续消除碘缺乏病的干预模式。方法采取综合干预措施:政府重视、普及碘盐、部门协作、开设碘缺乏病门诊、重点干预、注重宣传教育等,并对其效果进行评价。结果易县儿童甲状腺肿患病率自1998年至2011年连续14年一直控制在5%以内;合格碘盐食用率自1996年至2011年连续16年均在90%以上;儿童尿碘中位数自1995年至2011年连续17年均在100μg/L以上。结论所采取的综合干预模式及方法是实现可持续消除碘缺乏病行之有效的方法。

  2. Determination of iodine and bromine in coal and atmospheric particles by inductively coupled plasma mass spectrometry.

    Science.gov (United States)

    Sun, Mingxing; Gao, Yunchuan; Wei, Biwen; Wu, Xiaowei

    2010-04-15

    Bromine and iodine in atmospheric particles or coal can cause environmental problems such as destruction of ozone in the atmosphere; therefore, the presence of these compounds has recently received increased attention. Here, a rapid and reliable method for the simultaneous determination of total bromine and iodine using ICP-MS analysis is described. Samples were dissolved in mixtures of 5 mL of HNO(3) and 2 mL of H(2)O(2) in a high pressure microwave digester. The solution was then oxidized by per-sulfate (Na(2)S(2)O(8)) in addition to a small amount of silver nitrate, after which the total bromine and iodine were measured simultaneously by ICP-MS. The signal memory effects of bromine and iodine during analysis were effectively decreased by washing with a new mixture agent (2% alcohol acidic solution, pH 1-2 adjusted with HCl). The detection limits for bromine and iodine using this method were about 3.2 microg L(-1) and 1.1 microg L(-1), respectively. Additionally, the spike recoveries were between 78.7% and 121% for bromine and iodine analysis, while the relative standard deviations ranged from 4.3% to 9.7%, and from 1.5% to 3.4% for bromine and iodine, respectively. The results of this study indicate that the method described here is suitable for the analysis of micro-amounts of bromine and iodine in atmospheric particles and coal samples.

  3. Complete Initial Scoping Tests on the Incorporation of Novel Loaded Iodine Getters into GCM.

    Energy Technology Data Exchange (ETDEWEB)

    Nenoff, Tina M. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Garino, Terry J. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Croes, Kenneth James [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2015-08-18

    This study encompasses initial scoping tests on the incorporation of a novel iodine loaded getter material into the Sandia developed low temperature sintering glass ceramic material (GCM) waste form. In particular, we studied the PNNL Ag-I-Aerogel. Optical microscopy indicates inhomogenous samples based on particle sizes and variations in color (AgI vs Ag/AgO on silica). TGA/MS data when heated in air indicates loss of iodine and organics (CO2) between 250-450°C a total of ~15wt% loss, with additional / small iodine loss when during 550°C hold for 1 hr. TGA/MS data when heated in N2 indicates less organic and slightly less iodine loss below 550°C, with no loss of iodine in 550°C 1 hour hold. Furthermore, a substantial mass loss of sulfur containing compounds is observed (m/e of 34 and 36) between 150 – 550°C in both air and N2 sintering atmospheres. In an effort to capture iodine lost to volatilization during heating (at temps below glass sintering temperature of 550°C), we added 5 wt% Ag flake to the AgIaerogel. Resulting data indicates the iodine is retained with the addition of the Ag flake, resulting in only a small iodine loss (< 1wt%) at ~350°C. No method of curtailing loss of sulfur containing compounds due to heating was successful in this scoping study.

  4. Additive Manufacturing Modeling and Simulation A Literature Review for Electron Beam Free Form Fabrication

    Science.gov (United States)

    Seufzer, William J.

    2014-01-01

    Additive manufacturing is coming into industrial use and has several desirable attributes. Control of the deposition remains a complex challenge, and so this literature review was initiated to capture current modeling efforts in the field of additive manufacturing. This paper summarizes about 10 years of modeling and simulation related to both welding and additive manufacturing. The goals were to learn who is doing what in modeling and simulation, to summarize various approaches taken to create models, and to identify research gaps. Later sections in the report summarize implications for closed-loop-control of the process, implications for local research efforts, and implications for local modeling efforts.

  5. Iodine adsorption on Ni(111): STM and DFT study

    Science.gov (United States)

    Komarov, N. S.; Pavlova, T. V.; Andryushechkin, B. V.

    2016-09-01

    Iodine adsorption on the Ni(111) surface has been studied in ultra-high vacuum conditions with scanning tunneling microscopy (STM), Auger electron spectroscopy (AES), low-energy electron diffraction (LEED) and density functional theory (DFT) calculations. At the first stage of adsorption, iodine was found to form a simple commensurate (√{ 3 } ×√{ 3 }) R 30∘ structure at the coverage of 0.33 ML. According to DFT calculations, all iodine atoms in the (√{ 3 } ×√{ 3 }) R 30∘ structure occupy fcc hollow sites. Increase of the coverage in the range of (0.333 ML <θ < 0.364 ML) results in the uniaxial compression of the iodine lattice and the formation of the high-order commensurate structure (11 ×√{ 3 } R 30∘). The mechanism of compression involves the formation and the development of the striped super-heavy domain wall network. Further iodine dosing gives rise to nucleation and growth of flat 2D islands of surface nickel iodide. Atomic resolution STM images of iodide islands, in addition to atomic modulation, exhibit clear visible moiré-like superstructures with a period about 26 Å. The origin of the moiré-patterns was explained by the incommensurability of lattices of the surface nickel iodide and underlying Ni(111).

  6. Lack of Dietary Sources of Iodine and the Prevalence of Iodine ...

    African Journals Online (AJOL)

    Lack of Dietary Sources of Iodine and the Prevalence of Iodine Deficiency in Rural Women ... Log in or Register to get access to full text downloads. ... to assess urinary iodine concentration (UIC), goiter and dietary intake of iodine in a sample of ... Hence, there is a need to supply iodized salt in order to achieve the goal of ...

  7. Stiffness Model of a 3-DOF Parallel Manipulator with Two Additional Legs

    Directory of Open Access Journals (Sweden)

    Guang Yu

    2014-10-01

    Full Text Available This paper investigates the stiffness modelling of a 3-DOF parallel manipulator with two additional legs. The stiffness model in six directions of the 3-DOF parallel manipulator with two additional legs is derived by performing condensation of DOFs for the joint connection and treatment of the fixed-end connections. Moreover, this modelling method is used to derive the stiffness model of the manipulator with zero/one additional legs. Two performance indices are given to compare the stiffness of the parallel manipulators with two additional legs with those of the manipulators with zero/one additional legs. The method not only can be used to derive the stiffness model of a redundant parallel manipulator, but also to model the stiffness of non-redundant parallel manipulators.

  8. Urinary Iodine Concentrations Indicate Iodine Deficiency in Pregnant Thai Women but Iodine Sufficiency in Their School-Aged Children

    NARCIS (Netherlands)

    Gowachirapant, S.; Winichagoon, P.; Wyss, L.; Tong, B.; Baumgartner, J.; Boonstra, A.; Zimmermann, M.B.

    2009-01-01

    The median urinary iodine concentration (UI) in school-aged children is recommended for assessment of iodine nutrition in populations. If the median UI is adequate in school-aged children, it is usually assumed iodine intakes are also adequate in the remaining population, including pregnant women. B

  9. Iodine Hall Thruster for Space Exploration Project

    Data.gov (United States)

    National Aeronautics and Space Administration — In the Phase I program, Busek Co. Inc. tested an existing Hall thruster, the BHT-8000, on iodine propellant. The thruster was fed by a high flow iodine feed system,...

  10. Iodine 131 ablation of an obstructive lingual thyroid

    Directory of Open Access Journals (Sweden)

    Lester Johnson

    2009-01-01

    Full Text Available A 48-year-old woman undergoing surgery could not be intubated because of an oropharyngeal mass. CT and MRI revealed a 3 cm possible lingual thyroid mass, confirmed by Iodine-123 SPECT/CT. The patient underwent successful Iodine-131 ablation and has done well on thyroid hormone-replacement therapy. This case also demonstrates how modern cross-sectional imaging like SPECT/CT can appropriately be used in the patient diagnosis and management, and is of additional interest for including pre- and post-therapy MRI documenting efficacy morphologically.

  11. Iodine content in bread and salt in Denmark after iodization and the influence on iodine intake

    DEFF Research Database (Denmark)

    Rasmussen, Lone Banke; Ovesen, Lars; Christensen, Tue;

    2007-01-01

    Objective To measure the iodine content in bread and household salt in Denmark after mandatory iodine fortification was introduced and to estimate the increase in iodine intake due to the fortification. Design The iodine content in rye breads, wheat breads and salt samples was assessed....... The increase in iodine intake from fortification of bread and the increase in total iodine intake after fortification were estimated. Subjects Iodine intake before and after fortification was estimated based on dietary intake data from 4,124 randomly selected Danish subjects. Main results Approximately 98......% of the rye breads and 90% of the wheat breads were iodized. The median iodine intake from bread increased by 25 ( 13-43) mu g/day and the total median iodine intake increased by 63 (36-104) mu g/day. Conclusions The fortification of bread and salt has resulted in a desirable increase in iodine intake...

  12. Dietary restriction causing iodine-deficient goitre.

    Science.gov (United States)

    Cheetham, Tim; Plumb, Emma; Callaghan, James; Jackson, Michael; Michaelis, Louise

    2015-08-01

    Iodine-deficient goitre was common in some parts of the UK prior to the introduction of salt iodisation. Many contemporary salt preparations do not contain much iodine, and there are renewed concerns about the iodine status of the population. We present a boy with severe allergy who developed goitre and significant thyroid dysfunction in association with an iodine-deficient 'food-restricted' diet. The case highlights the importance of a comprehensive nutritional assessment in all children on multiple food restrictions.

  13. Contrast induced hyperthyroidism due to iodine excess

    OpenAIRE

    Mushtaq, Usman; Price, Timothy; Laddipeerla, Narsing; Townsend, Amanda; Broadbridge, Vy

    2009-01-01

    Iodine induced hyperthyroidism is a thyrotoxic condition caused by exposure to excessive iodine. Historically this type of hyperthyroidism has been described in areas of iodine deficiency. With advances in medicine, iodine induced hyperthyroidism has been observed following the use of drugs containing iodine—for example, amiodarone, and contrast agents used in radiological imaging. In elderly patients it is frequently difficult to diagnose and control contrast related hyperthyroidism, as most...

  14. Mineral resource of the month: iodine

    Science.gov (United States)

    Polyak, Désirée E.

    2009-01-01

    The article focuses on iodine, its benefits and adverse effects, and its production and consumption. It states that iodine is essential to humans for it produces thyroid hormones to nourish thyroid glands but excessive intake could cause goiter, hyperthyroidism or hypothyroidism. U.S. laws require salt iodization to help prevent diseases. Chile and Japan are the world's leading iodine producer while in the U.S. iodine is mined from deep well brines in northern Oklahoma.

  15. Spatial variability of drinking water iodine in Denmark: implications for future policy making

    Science.gov (United States)

    Voutchkova, Denitza; Ernstsen, Vibeke; Kristiansen, Søren; Hansen, Birgitte

    2014-05-01

    The iodine-an essential component of human thyroid hormones-is provided to our organisms naturally from the food and water and/or is added artificially to the diet. One of the major natural contributors to the dietary iodine intake in Denmark is the drinking water. Both insufficient or excessive iodine intake can cause health problems however the attention falls mainly on the iodine deficiency (ID). Denmark is classified to have mild ID, which is based on sub-national data only. On a bigger scale, in Europe, about 40% of the general population is estimated to suffer from insufficient iodine intake (based on recent update on the iodine status worldwide). A mandatory addition of iodine to the salt was introduced in 2001 in Denmark to address the population's mild deficiency. One of the components of the Danish monitoring program investigating the effect of the salt iodizing (DanThyr) was based on the geographical variation of drinking water iodine levels. More specifically, the location of the two DanThyr cohort studies was chosen to reflect the low concentrations in the western part of Denmark and higher concentration in the eastern part. However, the knowledge about the spatial variability of iodine in Danish ground- and drinking water at that time was quite limited and misrepresentation of the natural variability is suspected. The presented sampling campaign was completed in 2013, and includes 144 waterworks with annual abstraction of about 175 mio m3 groundwater (~45% of the total groundwater abstraction by all active public and private Danish waterworks). The results show a surprisingly complex spatial pattern concerning both the iodine concentrations and speciation. By estimating the dietary iodine intake from water and comparing it to the WHO recommendations, it becomes possible to recognize potentially deficient/excessive geographical areas. Moreover, it is demonstrated that drinking water iodine levels (major dietary iodine contributor in Denmark) can be

  16. Sublimation of Iodine at Various Pressures

    Science.gov (United States)

    Leenson, Ilya A.

    2005-01-01

    Various phenomena that are observed in the process of heating solid iodine in closed vessels at different pressures and temperatures are described. When solid iodine is heated in an evacuated ampoule where the pressure is less than 10(super -3), no noticeable color appears and immediate condensation of tiny iodine crystals is visible higher up on…

  17. Iodine in Enteral and Parenteral Nutrition

    NARCIS (Netherlands)

    Zimmermann, M.B.; Crill, C.M.

    2010-01-01

    Iodine deficiency (ID) has multiple adverse effects on growth and development due to inadequate thyroid hormone production. Methods for assessment of iodine nutrition in individuals include the urinary iodine concentration (UI), thyroid size and thyroid function tests. The UI measured in several rep

  18. Iodine excretion in school children in Copenhagen

    DEFF Research Database (Denmark)

    Rasmussen, Lone B; Kirkegaard-Klitbo, Ditte Marie; Laurberg, Peter

    2016-01-01

    INTRODUCTION: Studies of dietary habits show a high iodine intake in children in Denmark. Iodine excretion in children has not previously been assessed. Iodine excretion in adults is below the recommended threshold, and it is therefore being discussed to increase the fortification level. The main...

  19. Determination of iodine and iodine compounds in marine samples by ICPMS and HPLC-ICPMS

    DEFF Research Database (Denmark)

    Hansen, Maiken Sødergreen; Lewandowski, Daniel Jacob; Rasmussen, Rie Romme

    2014-01-01

    for determining the different iodine species. For determining the total iodine concentration in marine samples five different extraction methods were compared. The most efficient and precise method was then used for determining the total concentration of iodine in seaweed and fish samples using inductively...... (HPLC) coupled to ICPMS. These studies may be a stepping stone for further studies that can clarify the cycle and implications of iodine species in relation to the use of marine food items as iodine sources....

  20. Infinite Polyiodide Chains in the Pyrroloperylene-Iodine Complex: Insights into the Starch-Iodine and Perylene-Iodine Complexes.

    Science.gov (United States)

    Madhu, Sheri; Evans, Hayden A; Doan-Nguyen, Vicky V T; Labram, John G; Wu, Guang; Chabinyc, Michael L; Seshadri, Ram; Wudl, Fred

    2016-07-04

    We report the preparation and X-ray crystallographic characterization of the first crystalline homoatomic polymer chain, which is part of a semiconducting pyrroloperylene-iodine complex. The crystal structure contains infinite polyiodide I∞ (δ-) . Interestingly, the structure of iodine within the insoluble, blue starch-iodine complex has long remained elusive, but has been speculated as having infinite chains of iodine. Close similarities in the low-wavenumber Raman spectra of the title compound and starch-iodine point to such infinite polyiodide chains in the latter as well. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  1. Comparison of computational models for estimation of whole body and organ radiation dose in rainbow trout from uptake of iodine-131 - Comparison of rainbow trout phantoms for estimation of whole body and organ radiation dose rates from uptake of iodine-131 in freshwater systems

    Energy Technology Data Exchange (ETDEWEB)

    Martinez, Nicole E. [Department of Environmental and Engineering Sciences, Clemson University, Clemson, South Carolina, 29634 (United States); Johnson, Thomas E.; Ruedig, Elizabeth; Pinder, John E. III [Department of Environmental and Radiological Health Sciences, Colorado State University, 1681 Campus Delivery, Fort Collins, Colorado, 80523 (United States)

    2014-07-01

    Internal radiation dose rates to biota are typically calculated utilizing dose conversion factors (DCF), which are values for absorbed dose rate per activity concentration (i.e. mGy d{sup -1} per Bq g{sup -1}). The current methodology employed by both the ICRP and within the ERICA Integrated Approach for calculating dose conversion coefficients is to use Monte Carlo modeling of a homogeneously distributed radionuclide within an ellipsoidal phantom chosen to represent a particular organism. It has been shown that for whole-body DCF, homogenous distribution is a reasonable assumption for electrons, and is associated with an uncertainty of less than 30% for photons. However, if a radionuclide has a specific tissue tropism (e.g. iodine-131 in thyroid) a much higher dose will be received by the organ or tissue than by the whole body. Internal organs are modeled generically as spheres within the ellipsoid phantom, due to the complex and variable nature of organ structure and arrangement within different types of organisms. Ratios of whole-body to organ mass offer conservative conversions of whole-body to organ specific DCF (Gomez-Ros et al 2008), but may considerably overestimate the organ dose; more accurate estimates can be made based on specific absorbed fractions and activity concentrations. Establishment of appropriate screening levels in the regulatory paradigm requires incorporation of sufficient knowledge of dose effects; the ICRP currently lists no derived consideration reference levels for organs, meaning that specific risks associated with organ dose rates are unavailable (ICRP 108). Model comparison and refinement is important in the process of determining both dose rates and dose effects, and here we develop and compare three models for rainbow trout (Oncorhynchus mykiss): the simple geometry described above, a more specific geometry employing anatomically relevant organ size and location, and voxel reconstruction of internal anatomy obtained from CT imaging

  2. An introduction to modeling longitudinal data with generalized additive models: applications to single-case designs.

    Science.gov (United States)

    Sullivan, Kristynn J; Shadish, William R; Steiner, Peter M

    2015-03-01

    Single-case designs (SCDs) are short time series that assess intervention effects by measuring units repeatedly over time in both the presence and absence of treatment. This article introduces a statistical technique for analyzing SCD data that has not been much used in psychological and educational research: generalized additive models (GAMs). In parametric regression, the researcher must choose a functional form to impose on the data, for example, that trend over time is linear. GAMs reverse this process by letting the data inform the choice of functional form. In this article we review the problem that trend poses in SCDs, discuss how current SCD analytic methods approach trend, describe GAMs as a possible solution, suggest a GAM model testing procedure for examining the presence of trend in SCDs, present a small simulation to show the statistical properties of GAMs, and illustrate the procedure on 3 examples of different lengths. Results suggest that GAMs may be very useful both as a form of sensitivity analysis for checking the plausibility of assumptions about trend and as a primary data analysis strategy for testing treatment effects. We conclude with a discussion of some problems with GAMs and some future directions for research on the application of GAMs to SCDs.

  3. Estimation of additive and dominance variance for reproductive traits from different models in Duroc purebred

    OpenAIRE

    Talerngsak Angkuraseranee

    2010-01-01

    The additive and dominance genetic variances of 5,801 Duroc reproductive and growth records were estimated usingBULPF90 PC-PACK. Estimates were obtained for number born alive (NBA), birth weight (BW), number weaned (NW), andweaning weight (WW). Data were analyzed using two mixed model equations. The first model included fixed effects andrandom effects identifying inbreeding depression, additive gene effect and permanent environments effects. The secondmodel was similar to the first model, but...

  4. Additive Hazard Regression Models: An Application to the Natural History of Human Papillomavirus

    Directory of Open Access Journals (Sweden)

    Xianhong Xie

    2013-01-01

    Full Text Available There are several statistical methods for time-to-event analysis, among which is the Cox proportional hazards model that is most commonly used. However, when the absolute change in risk, instead of the risk ratio, is of primary interest or when the proportional hazard assumption for the Cox proportional hazards model is violated, an additive hazard regression model may be more appropriate. In this paper, we give an overview of this approach and then apply a semiparametric as well as a nonparametric additive model to a data set from a study of the natural history of human papillomavirus (HPV in HIV-positive and HIV-negative women. The results from the semiparametric model indicated on average an additional 14 oncogenic HPV infections per 100 woman-years related to CD4 count < 200 relative to HIV-negative women, and those from the nonparametric additive model showed an additional 40 oncogenic HPV infections per 100 women over 5 years of followup, while the estimated hazard ratio in the Cox model was 3.82. Although the Cox model can provide a better understanding of the exposure disease association, the additive model is often more useful for public health planning and intervention.

  5. Size Control in the Nanoprecipitation Process of Stable Iodine (¹²⁷I) Using Microchannel Reactor-Optimization by Artificial Neural Networks.

    Science.gov (United States)

    Aghajani, Mohamad Hosein; Pashazadeh, Ali Mahmoud; Mostafavi, Seyed Hossein; Abbasi, Shayan; Hajibagheri-Fard, Mohammad-Javad; Assadi, Majid; Aghajani, Mahdi

    2015-10-01

    In this study, nanosuspension of stable iodine ((127)I) was prepared by nanoprecipitation process in microfluidic devices. Then, size of particles was optimized using artificial neural networks (ANNs) modeling. The size of prepared particles was evaluated by dynamic light scattering. The response surfaces obtained from ANNs model illustrated the determining effect of input variables (solvent and antisolvent flow rate, surfactant concentration, and solvent temperature) on the output variable (nanoparticle size). Comparing the 3D graphs revealed that solvent and antisolvent flow rate had reverse relation with size of nanoparticles. Also, those graphs indicated that the solvent temperature at low values had an indirect relation with size of stable iodine ((127)I) nanoparticles, while at the high values, a direct relation was observed. In addition, it was found that the effect of surfactant concentration on particle size in the nanosuspension of stable iodine ((127)I) was depended on the solvent temperature. Nanoprecipitation process of stable iodine (127I) and optimization of particle size using ANNs modeling.

  6. [Effectiveness of the use of iodized milk protein to improve girls' sufficiency with iodine].

    Science.gov (United States)

    Bol'shakova, L S; Lisitsin, A B; Chernukha, I M; Zubtsov, Iu N; Litvinova, E V

    2014-01-01

    The work presents the results of the research capabilities of the use of iodized milk protein as a component of food supplement and enriched food product for the correction of iodine sufficiency in girls. Milk iodinated protein was produced by the enzyme-effective iodization of amino acid residues of cow's milk whey proteins. The study involved 30 girls, whose average age was 19.9 +/- 1.4 years. Participants of observation were divided into three groups, for 10 people each. The first group received daily serving of meat cutlets (50g), enriched with dairy iodinated protein. Iodine content in the finished minced was 100 mcg. The second group received iodinated milk protein in the form of food supplement with iodine content of 100 mcg. The third group was a control one. The duration of observations was 30 days. To assess the effectiveness of measures the concentration of iodine in urine, blood levels of thyroid-stimulating hormone and free thyroxine have been determined, changes in cognitive processes (memory and attention) with the use of psychological tests have been evaluated. Studies have shown the effectiveness of using of iodized milk protein for the correction of iodine deficiency in girls. The use of iodized protein, as part of the enriched product and in the form of food supplement increased urinary iodine level and had a positive influence on the state of the hypophysial-thyroid system. In addition, the use of iodized milk protein helped to improve the cognitive functions of the students, which can be considered as an additional positive effect of correction of iodine deficiency.

  7. Poor Knowledge and Practices Related to Iodine Nutrition during Pregnancy and Lactation in Australian Women: Pre- and Post-Iodine Fortification

    Directory of Open Access Journals (Sweden)

    Fiona Houweling

    2012-09-01

    Full Text Available A before-after review was undertaken to assess whether knowledge and practices related to iodine nutrition, supplementation and fortification has improved in Australian women since the introduction of mandatory iodine fortification in 2009. Surveys of pregnant (n = 139 and non-pregnant (n = 75 women in 2007–2008 are compared with surveys of pregnant (n = 147 and lactating women (n = 60 one to two years post-fortification in a regional area of New South Wales, Australia. A self-administered questionnaire was completed and dietary intake of iodine was assessed using a validated food frequency questionnaire. A generally poor knowledge about the role and sources of iodine in the diet remained after fortification. Post-fortification, iodine-containing supplements were being taken by 60% (up from 20% pre-fortification and 45% of pregnant and lactating women, respectively. Dairy foods were the highest contributors to dietary iodine intake (57%–62%. A low intake of fish and seafood resulted in this food group contributing only 3%–8% of total intake. A low level of public awareness regarding the role of iodine in health supports the need for public health strategies in addition to fortification, such as an accompanying consumer education campaign, increased uptake of supplementation, and on-going monitoring.

  8. The effect of preliminary processing and different methods of cooking on the iodine content and selected antioxidative properties of carrot (Daucus carota L. biofortified with (potassium iodine

    Directory of Open Access Journals (Sweden)

    Kapusta-Duch Joanna

    2017-06-01

    Full Text Available Carrot is a vegetable that contains many nutrients and has strong antioxidant activity as well as pro-health potential. The level of bioactive compounds is strongly connected with the production chain. The thermal treatment of food products induces several biological, physical and chemical changes. In this study, changes in the levels of iodine, total carotenoids, total polyphenols as well as the antioxidant activity of unpeeled and peeled controls and carrots biofortified with (potassium iodine (KJ during cultivation due to the cooking and steaming process were investigated. The use of thermal processes resulted in a lower concentration of iodine in the roots of the control as well as in carrots biofortified with (potassium iodine. In addition, peeling carrots caused higher losses of this trace element in the control and the biofortified carrots cooked or steamed for various times. In this study, a significant growth of the total carotenoids in peeled carrots biofortified with (potassium iodine and of the total polyphenols in unpeeled carrots biofortified with (potassium iodine under the influence of the cooking and steaming processes was observed compared with raw peeled and unpeeled biofortified carrots, respectively. Antioxidant activity significantly increased in the unpeeled and peeled carrots biofortified with (potassium iodine under all thermal treatments in comparison with the raw unpeeled and peeled biofortified carrots.

  9. Poor knowledge and practices related to iodine nutrition during pregnancy and lactation in Australian women: pre- and post-iodine fortification.

    Science.gov (United States)

    Charlton, Karen; Yeatman, Heather; Lucas, Catherine; Axford, Samantha; Gemming, Luke; Houweling, Fiona; Goodfellow, Alison; Ma, Gary

    2012-09-01

    A before-after review was undertaken to assess whether knowledge and practices related to iodine nutrition, supplementation and fortification has improved in Australian women since the introduction of mandatory iodine fortification in 2009. Surveys of pregnant (n = 139) and non-pregnant (n = 75) women in 2007-2008 are compared with surveys of pregnant (n = 147) and lactating women (n = 60) one to two years post-fortification in a regional area of New South Wales, Australia. A self-administered questionnaire was completed and dietary intake of iodine was assessed using a validated food frequency questionnaire. A generally poor knowledge about the role and sources of iodine in the diet remained after fortification. Post-fortification, iodine-containing supplements were being taken by 60% (up from 20% pre-fortification) and 45% of pregnant and lactating women, respectively. Dairy foods were the highest contributors to dietary iodine intake (57%-62%). A low intake of fish and seafood resulted in this food group contributing only 3%-8% of total intake. A low level of public awareness regarding the role of iodine in health supports the need for public health strategies in addition to fortification, such as an accompanying consumer education campaign, increased uptake of supplementation, and on-going monitoring.

  10. Direct preparation of copper organometallics bearing an aldehyde function via an iodine-copper exchange.

    Science.gov (United States)

    Yang, Xiaoyin; Knochel, Paul

    2006-06-21

    The iodine-copper exchange reaction allows the direct preparation of various aryl, heteroaryl and alkenyl cuprates bearing a formyl group, thus allowing a direct synthesis of polyfunctional aldehydes without the need of protecting groups or an additional oxidation step.

  11. EFSA NDA Panel (EFSA Panel on Panel on Dietetic Products Nutrition and Allergies), 2014. Scientific Opinion on Dietary Reference Values for iodine

    DEFF Research Database (Denmark)

    Tetens, Inge

    /day. For pregnant women, an AI of 200 µg/day is proposed, taking into account additional needs due to increased maternal thyroid hormone production and the iodine uptake by the fetus, placenta and amniotic fluid. The proposed AI for lactating women of 200 µg/day takes into account the existence of large iodine...... stores in conditions of adequate iodine status before pregnancy and considers that a full compensation for the iodine secreted in breast milk is not justified for the derivation of an AI for iodine for lactating women....

  12. Dietary flavonoids and iodine Metabolism

    NARCIS (Netherlands)

    Elst, van der J.P.; Smit, J.W.A.; Romijn, H.A.; Heide, van der D.

    2003-01-01

    Flavonoids have inhibiting effects on the proliferation of cancer cells, including thyroidal ones. In the treatment of thyroid cancer the uptake of iodide is essential. Flavonoids are known to interfere with iodide organification ill vitro, and to cause goiter. The influence of flavonoids on iodine

  13. Thyroid disorders in mild iodine deficiency.

    Science.gov (United States)

    Laurberg, P; Nøhr, S B; Pedersen, K M; Hreidarsson, A B; Andersen, S; Bülow Pedersen, I; Knudsen, N; Perrild, H; Jørgensen, T; Ovesen, L

    2000-11-01

    Comparative epidemiologic studies in areas with low and high iodine intake and controlled studies of iodine supplementation have demonstrated that the major consequence of mild-to-moderate iodine deficiency for the health of the population is an extraordinarily high occurrence of hyperthyroidism in elderly subjects, especially women, with risk of cardiac arrhythmias, osteoporosis, and muscle wasting. The hyperthyroidism is caused by autonomous nodular growth and function of the thyroid gland and it is accompanied by a high frequency of goiter. Pregnant women and small children are not immediately endangered but the consequences of severe iodine deficiency for brain development are grave and a considerable safety margin is advisable. Moreover, a shift toward less malignant types of thyroid cancer and a lower radiation dose to the thyroid in case of nuclear fallout support that mild-to-moderate iodine deficiency should be corrected. However, there is evidence that a high iodine intake may be associated with more autoimmune hypothyroidism, and that Graves' disease may manifest at a younger age and be more difficult to treat. Hence, the iodine intake should be brought to a level at which iodine deficiency disorders are avoided but not higher. Iodine supplementation programs should aim at relatively uniform iodine intake, avoiding deficient or excessive iodine intake in subpopulations. To adopt such a strategy, surveillance programs are needed.

  14. Expanded Analysis of Hot Isostatic Pressed Iodine-Loaded Silver-Exchanged Mordenite

    Energy Technology Data Exchange (ETDEWEB)

    Jubin, R. T. [ORNL; Bruffey, S. H. [ORNL; Patton, K. K. [ORNL

    2014-09-30

    variations, and an expanded temperature range. Each sample was analyzed with the approach used in Phase I. In all cases, there is nothing in the SEM or XRD analyses that indicates creation of any AgI-containing silicon phase, with the samples being found to be largely amorphous. Phase III of this study has been initiated and is the final phase of scoping tests. It will expand upon the test matrix completed in Phase II and will examine the durability of the pressed pellets through product consistency testing (PCT) studies. Transformation of the component material into a well-characterized iodine-containing mineral phase would be desirable. This would limit the additional experimental testing and modeling required to determine the long-term stability of the pressed pellet, as much of that information has already been learned for several common iodine-containing minerals. However, this is not an absolute requirement, especially if pellets produced by hot isostatic pressing can be demonstrated through initial PCT studies to retain iodine well despite their amorphous composition.

  15. Product versus additive threshold models for analysis of reproduction outcomes in animal genetics.

    Science.gov (United States)

    David, I; Bodin, L; Gianola, D; Legarra, A; Manfredi, E; Robert-Granié, C

    2009-08-01

    The phenotypic observation of some reproduction traits (e.g., insemination success, interval from lambing to insemination) is the result of environmental and genetic factors acting on 2 individuals: the male and female involved in a mating couple. In animal genetics, the main approach (called additive model) proposed for studying such traits assumes that the phenotype is linked to a purely additive combination, either on the observed scale for continuous traits or on some underlying scale for discrete traits, of environmental and genetic effects affecting the 2 individuals. Statistical models proposed for studying human fecundability generally consider reproduction outcomes as the product of hypothetical unobservable variables. Taking inspiration from these works, we propose a model (product threshold model) for studying a binary reproduction trait that supposes that the observed phenotype is the product of 2 unobserved phenotypes, 1 for each individual. We developed a Gibbs sampling algorithm for fitting a Bayesian product threshold model including additive genetic effects and showed by simulation that it is feasible and that it provides good estimates of the parameters. We showed that fitting an additive threshold model to data that are simulated under a product threshold model provides biased estimates, especially for individuals with high breeding values. A main advantage of the product threshold model is that, in contrast to the additive model, it provides distinct estimates of fixed effects affecting each of the 2 unobserved phenotypes.

  16. Concentration addition, independent action and generalized concentration addition models for mixture effect prediction of sex hormone synthesis in vitro

    DEFF Research Database (Denmark)

    Hadrup, Niels; Taxvig, Camilla; Pedersen, Mikael;

    2013-01-01

    , antagonism was observed for effects of Mixture 2 on this hormone. The mixtures contained chemicals exerting only limited maximal effects. This hampered prediction by the CA and IA models, whereas the GCA model could be used to predict a full dose response curve. Regarding effects on progesterone...

  17. Effects of additional food in a delayed predator-prey model.

    Science.gov (United States)

    Sahoo, Banshidhar; Poria, Swarup

    2015-03-01

    We examine the effects of supplying additional food to predator in a gestation delay induced predator-prey system with habitat complexity. Additional food works in favor of predator growth in our model. Presence of additional food reduces the predatory attack rate to prey in the model. Supplying additional food we can control predator population. Taking time delay as bifurcation parameter the stability of the coexisting equilibrium point is analyzed. Hopf bifurcation analysis is done with respect to time delay in presence of additional food. The direction of Hopf bifurcations and the stability of bifurcated periodic solutions are determined by applying the normal form theory and the center manifold theorem. The qualitative dynamical behavior of the model is simulated using experimental parameter values. It is observed that fluctuations of the population size can be controlled either by supplying additional food suitably or by increasing the degree of habitat complexity. It is pointed out that Hopf bifurcation occurs in the system when the delay crosses some critical value. This critical value of delay strongly depends on quality and quantity of supplied additional food. Therefore, the variation of predator population significantly effects the dynamics of the model. Model results are compared with experimental results and biological implications of the analytical findings are discussed in the conclusion section.

  18. Iodine deficiency and associated factors among school children: a cross-sectional study in Ethiopia

    Directory of Open Access Journals (Sweden)

    Sintayehu Hailu

    2016-10-01

    Full Text Available Abstract Background Iodine deficiency remains a public health problem in the world. It is the leading cause of preventable mental retardation and brain damage worldwide. Though 12 million school age children are at risk of developing iodine deficiency, there is a scarcity of literature showing the magnitude of iodine deficiency in Ethiopia. Therefore, this study aimed to determine the prevalence and associated factors of iodine deficiency among school children in Robe District, southeast Ethiopia. Methods A school based cross–sectional study was conducted from February to June, 2015. A structured interviewer-administered questionnaire was used to collect data. A systematic random sampling technique was employed to select 422 children. A multivariate logistic regression analysis was carried out to identify factors associated with iodine deficiency. In the multivariate analysis, variables with a P-value of <0.05 were considered statistically significant. Results A total of 393 school children participated in the study. The median urinary iodine level was 78 μg/l. About 57 and 43.5 % of the children were found with low urinary iodine level and goiter, respectively. Only 29 % of the households utilized adequately iodized salt. The result of the multivariate analysis revealed that the odds of iodine deficiency were higher among female [AOR = 2.23; 95 % CI: 1.54, 3.55] and older (10–12 years [AOR = 2.21; 95 % CI: 1.44, 3.42] children. Conclusion In this community, the prevalence of goiter and low urine iodine level is high. Thus, iodine deficiency exists as severe public health problem. In addition, there is a low utilization of iodized salt in the setting. Therefore, it is crucial to intensify efforts in the implementation of iodized salt. Moreover, attention should be given to school children to address ID.

  19. Iodine deficiency and associated factors among school children: a cross-sectional study in Ethiopia.

    Science.gov (United States)

    Hailu, Sintayehu; Wubshet, Mamo; Woldie, Haile; Tariku, Amare

    2016-01-01

    Iodine deficiency remains a public health problem in the world. It is the leading cause of preventable mental retardation and brain damage worldwide. Though 12 million school age children are at risk of developing iodine deficiency, there is a scarcity of literature showing the magnitude of iodine deficiency in Ethiopia. Therefore, this study aimed to determine the prevalence and associated factors of iodine deficiency among school children in Robe District, southeast Ethiopia. A school based cross-sectional study was conducted from February to June, 2015. A structured interviewer-administered questionnaire was used to collect data. A systematic random sampling technique was employed to select 422 children. A multivariate logistic regression analysis was carried out to identify factors associated with iodine deficiency. In the multivariate analysis, variables with a P-value of iodine level was 78 μg/l. About 57 and 43.5 % of the children were found with low urinary iodine level and goiter, respectively. Only 29 % of the households utilized adequately iodized salt. The result of the multivariate analysis revealed that the odds of iodine deficiency were higher among female [AOR = 2.23; 95 % CI: 1.54, 3.55] and older (10-12 years) [AOR = 2.21; 95 % CI: 1.44, 3.42] children. In this community, the prevalence of goiter and low urine iodine level is high. Thus, iodine deficiency exists as severe public health problem. In addition, there is a low utilization of iodized salt in the setting. Therefore, it is crucial to intensify efforts in the implementation of iodized salt. Moreover, attention should be given to school children to address ID.

  20. Iodine status in pregnant women and school children of the Aira district in Ethiopia

    Directory of Open Access Journals (Sweden)

    Talila Keno

    2017-06-01

    Full Text Available Iodine deficiency is a public health problem in Ethiopia. This study was conducted to investigate the iodine status of pregnant women and school children of Aira district, west Ethiopia. A school-based survey of children and a clinic-based assessment that focused on pregnant women were conducted from May to June 2014. Spot urine and salt samples were collected and their iodine concentrations determined by an ammonium persulfate test and titration, respectively. Qualitative information was obtained by focus group discussions and individual interviews. The median urinary iodine excretion found in school children (n = 73 and pregnant women (n = 40 were 70.5 μg/l (95% CI, 48.1 μg/l–83.8 μg/l and 88.6 μg/l (95% CI, 66.9 μg/l–113.5 μg/l, respectively. About 72.6% of the school children and 80% of the pregnant women had insufficient iodine intake. 67% of household salt samples (n = 46 contained iodine ˂15 ppm. In addition to its health consequences, iodine deficiency has negative social impacts. A deformed physical appearance (with clinical signs of goitre entails psychological tensions, and is also considered to reduce chances for marriage. Iodine levels both in urine and salt samples indicated that the majority of school children and pregnant women from this study were at risk of iodine deficiency disorders. Thus, raising awareness about the nutritional importance of iodized salt and its proper packaging with sealed containers which reduce iodine loss should be promoted.

  1. Evaluation of (iodine-125)N,N,N'-trimethyl-N'-(2-hydroxy-3-methyl-5-iodobenzyl)-1,3- propanediamine lung uptake using an isolated-perfused lung model

    Energy Technology Data Exchange (ETDEWEB)

    Slosman, D.O.; Brill, A.B.; Polla, B.S.; Alderson, P.O.

    1987-02-01

    Lung uptake of N,N,N'-trimethyl-N'-(2-Hydroxy-3-methyl-5-iodobenzyl)-1,3- propanediamine (HIPDM) has been reported, but the mechanism of this process has not yet been established. Thus, single-pass (/sup 125/I)HIPDM accumulation was studied in rat lungs perfused with a Krebs-Ringer bicarbonate buffer containing 4.5% bovine albumin. Iodine-125 HIPDM lung accumulation was monitored by the percent of extraction per gram of lung tissue. Iodine-125 HIPDM lung uptake did not appear to occur by simple diffusion. As the time of perfusion was increased from 2 to 15 min, the rate of uptake of 2 microM (/sup 125/I)HIPDM decreased by 40%. During a 2-min perfusion, 98.6% +/- 6.7 (n = 8) extraction was observed with 2 microM (/sup 125/I)HIPDM, but only 38% +/- 2.0 (n = 3) was extracted when the (/sup 125/I)HIPDM concentration was 1 mM. The addition of 1 mM chlorpromazine, propranolol or imipramine also decreased (/sup 125/I)HIPDM lung uptake to 43.0% +/- 1.5, 51.4% +/- 2.2, and 49.8% +/- 0.8, respectively, (each n = 4 - 6, p less than 0.001). Cold (4 degrees C) had little effect on pulmonary accumulation (77.7% +/- 7.4, n = 5, p less than 0.01), and the addition of ouabain or the use of sodium-free medium had no effect. Thus, pulmonary (/sup 125/I)HIPDM accumulation does not appear to occur by sodium-dependent active transport. Rather, its uptake appears to be similar to the uptake of other basic amines, such as propranolol and imipramine, which are known to bind by physico-chemical interactions to pulmonary endothelial cell membranes and reflect pulmonary vascular surface area.

  2. Degree of multicollinearity and variables involved in linear dependence in additive-dominant models

    Directory of Open Access Journals (Sweden)

    Juliana Petrini

    2012-12-01

    Full Text Available The objective of this work was to assess the degree of multicollinearity and to identify the variables involved in linear dependence relations in additive-dominant models. Data of birth weight (n=141,567, yearling weight (n=58,124, and scrotal circumference (n=20,371 of Montana Tropical composite cattle were used. Diagnosis of multicollinearity was based on the variance inflation factor (VIF and on the evaluation of the condition indexes and eigenvalues from the correlation matrix among explanatory variables. The first model studied (RM included the fixed effect of dam age class at calving and the covariates associated to the direct and maternal additive and non-additive effects. The second model (R included all the effects of the RM model except the maternal additive effects. Multicollinearity was detected in both models for all traits considered, with VIF values of 1.03 - 70.20 for RM and 1.03 - 60.70 for R. Collinearity increased with the increase of variables in the model and the decrease in the number of observations, and it was classified as weak, with condition index values between 10.00 and 26.77. In general, the variables associated with additive and non-additive effects were involved in multicollinearity, partially due to the natural connection between these covariables as fractions of the biological types in breed composition.

  3. ADDITIVE-MULTIPLICATIVE MODEL FOR RISK ESTIMATION IN THE PRODUCTION OF ROCKET AND SPACE TECHNICS

    Directory of Open Access Journals (Sweden)

    Orlov A. I.

    2014-10-01

    Full Text Available For the first time we have developed a general additive-multiplicative model of the risk estimation (to estimate the probabilities of risk events. In the two-level system in the lower level the risk estimates are combined additively, on the top – in a multiplicative way. Additive-multiplicative model was used for risk estimation for (1 implementation of innovative projects at universities (with external partners, (2 the production of new innovative products, (3 the projects for creation of rocket and space equipmen

  4. Between and beyond additivity and non-additivity; the statistical modelling of genotype by environment interaction in plant breeding.

    NARCIS (Netherlands)

    Eeuwijk, van F.A.

    1996-01-01

    In plant breeding it is a common observation to see genotypes react differently to environmental changes. This phenomenon is called genotype by environment interaction. Many statistical approaches for analysing genotype by environment interaction rely heavily on the analysis of variance model. Genot

  5. Between and beyond additivity and non-additivity : the statistical modelling of genotype by environment interaction in plant breeding

    NARCIS (Netherlands)

    Eeuwijk, van F.A.

    1996-01-01

    In plant breeding it is a common observation to see genotypes react differently to environmental changes. This phenomenon is called genotype by environment interaction. Many statistical approaches for analysing genotype by environment interaction rely heavily on the analysis of variance model.

  6. Some quantitative aspects of the labelling of proteins with 125 I by the iodine monochloride method.

    Science.gov (United States)

    Ceska, M; Sjödin, A V; Grossmüller, F

    1971-01-01

    The labelling of proteins by the iodine monochloride method was studied by using a mathematical model. The equations used were primarily derived from the mass law equation of the isotopic exchange reaction between [(125)I]iodide and iodine monochloride. For convenient application, all equations were programmed into a computing desk-top calculator. To support the validity of the theoretical model, a series of iodinations of insulin were performed under various labelling conditions. The results of these experiments compare well with the theoretically derived values. Deviations from the theoretical values occurring at molar ratios of [(125)I]iodide to iodine monochloride 4.0 are explained and suggestions made about how to prevent them. The mathematical model was used to simulate the isotopic exchange, and the iodination reaction under various conditions, to study (a) the influence of the amount of [(125)I]iodide on the amount of [(125)I]iodine monochloride formed, (b) the influence of the specific radioactivity of [(125)I]iodide on the amount of [(125)I]iodine monochloride formed, and (c) the influence of the specific radioactivity of [(125)I]iodide on the number of millicuries needed for labelling to a desired extent.

  7. Speciation of iodine in high iodine groundwater in china associated with goitre and hypothyroidism.

    Science.gov (United States)

    Andersen, Stig; Guan, Haixia; Teng, Weiping; Laurberg, Peter

    2009-05-01

    Iodine intake affects the occurrence of disease in a population. Excessive iodine intake may be caused by a high iodine content of drinking water. Tap water in few locations in Europe contains up to 139 microg/L mostly bound to humic substances, probably leaching from marine sediments in the aquifers. Even higher iodine contents have been found in Chinese waters, previously shown to associate with goitre and hypothyroidism. The aims were to elucidate speciation of high iodine groundwater from deep wells in China and to compare with high iodine waters from Europe. Water was sampled from eight wells in five villages along Bohai Bay, China. Macro-molecules and low molecular weight (MW) substances were separated by size exclusion chromatography (high performance liquid chromatography, Superose 12 HR 10/30, buffer 0.1 M Tris, pH 7.0). Organic material was evaluated by A280 and iodine in fractions measured by the Ce/As method after alkaline incineration. Iodine content of well water varied from 135 to 880 microg/L (median 287 microg/L). The amount of organic material in water was low with A280, iodine eluted around K (AV) 0.65 corresponding to MW 5 kDa (humic substances) and one peak at V (total) (iodide/low MW substances). The fraction of iodine in macro-molecules, suggested to be humic substances, varied from 8% to 70% (median 27%). Iodine and peak absorbance were associated (p = 0.006). In conclusion, iodine in iodine-rich deep well water in northern China may have marine origin and may associate with humic substances, comparable to shallow well iodine-rich water in Europe. High iodine intake from iodine-rich water suggests the cause of endemic goitre and hypothyroidism in some areas in China being iodine.

  8. An estimating equation for parametric shared frailty models with marginal additive hazards

    DEFF Research Database (Denmark)

    Pipper, Christian Bressen; Martinussen, Torben

    2004-01-01

    Multivariate failure time data arise when data consist of clusters in which the failure times may be dependent. A popular approach to such data is the marginal proportional hazards model with estimation under the working independence assumption. In some contexts, however, it may be more reasonable...... to use the marginal additive hazards model. We derive asymptotic properties of the Lin and Ying estimators for the marginal additive hazards model for multivariate failure time data. Furthermore we suggest estimating equations for the regression parameters and association parameters in parametric shared...

  9. An original traffic additional emission model and numerical simulation on a signalized road

    Science.gov (United States)

    Zhu, Wen-Xing; Zhang, Jing-Yu

    2017-02-01

    Based on VSP (Vehicle Specific Power) model traffic real emissions were theoretically classified into two parts: basic emission and additional emission. An original additional emission model was presented to calculate the vehicle's emission due to the signal control effects. Car-following model was developed and used to describe the traffic behavior including cruising, accelerating, decelerating and idling at a signalized intersection. Simulations were conducted under two situations: single intersection and two adjacent intersections with their respective control policy. Results are in good agreement with the theoretical analysis. It is also proved that additional emission model may be used to design the signal control policy in our modern traffic system to solve the serious environmental problems.

  10. Multi-compartment iodine calculations with FIPLOC/IMPAIR

    Energy Technology Data Exchange (ETDEWEB)

    Ewig, F.; Allelein, H.J. [Gesellschaft fuer Anlagen- und Reaktorsicherheit mbH (GRS), Koeln (Germany); Schwarz, S.; Weber, G. [Gesellschaft fuer Anlagen- und Reaktorsicherheit (GRS) mbH, Garching (Germany)

    1996-12-01

    The multi-compartment containment code FIPLOC for the simulation of severe accidents in LWR plants was extended by the integration of the iodine model IMPAIR-3. The iodine model was changed for arbitrary compartment configurations and tightly coupled to the thermal hydraulic part. A main progress with the coupled version FIPLOC-3.0 is the sophisticated modelling of the aerosol iodine behaviour. In a PWR accident the mass of iodine is mainly released in form of CsI aerosol from the primary circuit. In IMPAIR-3 the aerosol behaviour of the species CsI, AgI and IO{sub 3}{sup -} is modelled in a very simplified way causing large uncertainties in the calculated distributions. The behaviour of these three aerosol species is treated by the aerosol model MAEROS/MGA. Agglomeration, particle growth by condensation and all deposition processes are calculated. The solubility effect for the hygroscopic species CsI and IO{sub 3}{sup -} are comprehended. Furthermore the impact of the iodine decay heat on the thermal hydraulic behaviour is considered. In order to test the code development a preliminary FIPLOC-3.0 calculation was done simulating a German PWR containment for the core melt scenario ND* according to the German risk study phase B. IN the calculation a contact of the core melt with the sump water was assumed and the containment vent line was opened after 70 hours. The result show that the different iodine species are distributed inhomogeneously within the containment. The CsI-aerosol concentrations differ by two orders of magnitude and the I{sub 2}-concentration even by three orders of magnitude. Most of the iodine is assumed to be released as CsI aerosol out of the primary circuit. Since it fastly deposits its contribution to the release into the environment is minor. CsI is however dissolved in the sump, where mainly the gaseous I{sub 2} is created which can react in the containment atmosphere to IO{sub 3}{sup -}. (author) 11 figs., 3 tabs., 12 refs.

  11. Multifold Increases in Turing Pattern Wavelength in the Chlorine Dioxide-Iodine-Malonic Acid Reaction-Diffusion System

    Science.gov (United States)

    Gaskins, Delora K.; Pruc, Emily E.; Epstein, Irving R.; Dolnik, Milos

    2016-07-01

    Turing patterns in the chlorine dioxide-iodine-malonic acid reaction were modified through additions of sodium halide salt solutions. The range of wavelengths obtained is several times larger than in the previously reported literature. Pattern wavelength was observed to significantly increase with sodium bromide or sodium chloride. A transition to a uniform state was found at high halide concentrations. The observed experimental results are qualitatively well reproduced in numerical simulations with the Lengyel-Epstein model with an additional chemically realistic kinetic term to account for the added halide and an adjustment of the activator diffusion rate to allow for interhalogen formation.

  12. Incorporating shape constraints in generalized additive modelling of the height-diameter relationship for Norway spruce

    Directory of Open Access Journals (Sweden)

    Natalya Pya

    2016-02-01

    Full Text Available Background: Measurements of tree heights and diameters are essential in forest assessment and modelling. Tree heights are used for estimating timber volume, site index and other important variables related to forest growth and yield, succession and carbon budget models. However, the diameter at breast height (dbh can be more accurately obtained and at lower cost, than total tree height. Hence, generalized height-diameter (h-d models that predict tree height from dbh, age and other covariates are needed. For a more flexible but biologically plausible estimation of covariate effects we use shape constrained generalized additive models as an extension of existing h-d model approaches. We use causal site parameters such as index of aridity to enhance the generality and causality of the models and to enable predictions under projected changeable climatic conditions. Methods: We develop unconstrained generalized additive models (GAM and shape constrained generalized additive models (SCAM for investigating the possible effects of tree-specific parameters such as tree age, relative diameter at breast height, and site-specific parameters such as index of aridity and sum of daily mean temperature during vegetation period, on the h-d relationship of forests in Lower Saxony, Germany. Results: Some of the derived effects, e.g. effects of age, index of aridity and sum of daily mean temperature have significantly non-linear pattern. The need for using SCAM results from the fact that some of the model effects show partially implausible patterns especially at the boundaries of data ranges. The derived model predicts monotonically increasing levels of tree height with increasing age and temperature sum and decreasing aridity and social rank of a tree within a stand. The definition of constraints leads only to marginal or minor decline in the model statistics like AIC. An observed structured spatial trend in tree height is modelled via 2-dimensional surface

  13. Estimate of influenza cases using generalized linear, additive and mixed models.

    Science.gov (United States)

    Oviedo, Manuel; Domínguez, Ángela; Pilar Muñoz, M

    2015-01-01

    We investigated the relationship between reported cases of influenza in Catalonia (Spain). Covariates analyzed were: population, age, data of report of influenza, and health region during 2010-2014 using data obtained from the SISAP program (Institut Catala de la Salut - Generalitat of Catalonia). Reported cases were related with the study of covariates using a descriptive analysis. Generalized Linear Models, Generalized Additive Models and Generalized Additive Mixed Models were used to estimate the evolution of the transmission of influenza. Additive models can estimate non-linear effects of the covariates by smooth functions; and mixed models can estimate data dependence and variability in factor variables using correlations structures and random effects, respectively. The incidence rate of influenza was calculated as the incidence per 100 000 people. The mean rate was 13.75 (range 0-27.5) in the winter months (December, January, February) and 3.38 (range 0-12.57) in the remaining months. Statistical analysis showed that Generalized Additive Mixed Models were better adapted to the temporal evolution of influenza (serial correlation 0.59) than classical linear models.

  14. The frequency of Hashimoto thyroiditis in children and the relationship between urinary iodine level and Hashimoto thyroiditis.

    Science.gov (United States)

    Doğan, Murat; Acikgoz, Emel; Acikgoz, Mehmet; Cesur, Yasar; Ariyuca, Sevil; Bektas, Mehmet Selcuk

    2011-01-01

    The aim of this study was to determine the frequency of thyroid autoimmunity in second grade primary school students and to examine the relationship between iodine and Hashimoto thyroiditis (HT). This was a cohort study performed with 1000 students. Urinary iodine levels, antithyroid peroxidase (anti-TPO) and antithyroglobulin (anti-Tg) antibodies were determined in all children. Children with anti-TPO or anti-Tg antibody positivity or with goiter were summoned for detailed examinations. In total, 36 cases (3.6%) were diagnosed as HT. The goiter frequency was found in 17.5% of the whole cohort. Additionally, iodine deficiency was found in 64.2% of all children. The median urinary iodine excretion was determined as 132 microg/L (range 382 microg/L) in the HT group, whereas it was 73 microg/L (range 390 microg/L) in children with goiter but without HT and 81 microg/L (range 394 microg/L) in normal children. The urinary iodine level of HT cases was significantly higher than the other two groups (p < 0.001). HT was also determined in 2% of patients with low urinary iodine levels, in 6.2% of patients with normal urinary iodine levels, and in 7.5% of patients with high urinary iodine levels. Our data demonstrates the close relationship between excessive iodine levels and autoimmunity.

  15. Urinary iodine concentrations indicate iodine deficiency in pregnant Thai women but iodine sufficiency in their school-aged children.

    Science.gov (United States)

    Gowachirapant, Sueppong; Winichagoon, Pattanee; Wyss, Laura; Tong, Bennan; Baumgartner, Jeannine; Melse-Boonstra, Alida; Zimmermann, Michael B

    2009-06-01

    The median urinary iodine concentration (UI) in school-aged children is recommended for assessment of iodine nutrition in populations. If the median UI is adequate in school-aged children, it is usually assumed iodine intakes are also adequate in the remaining population, including pregnant women. But iodine requirements sharply increase during pregnancy. In this study, our aim was to measure UI in pairs of pregnant women and their school-aged children from the same family, who were sharing meals, to directly assess whether a household food basket that supplies adequate iodine to school-aged children also meets the needs of pregnant women. UI was measured in spot urine samples from pairs (n = 302) of healthy pregnant mothers and their school-aged children in metropolitan Bangkok, Thailand. A dietary questionnaire was completed. The UI [median (range)] in the pregnant women {108 (11-558) microg/L [0.85 (0.086-4.41) micromol/L]} were lower than those of their school-aged children {200 (25-835) microg/L [1.58 (0.20-6.52) micromol/L]} (P iodine status in the children but mild-to-moderate iodine deficiency in their pregnant mothers. The estimated iodine intakes in the 2 groups were in the range of 130-170 microg/d. There was a modest positive correlation between UI in the pairs (r = 0.253; P iodine status in pregnancy in central Thailand; pregnant women should be directly monitored.

  16. Iodine excretion in school children in Copenhagen

    DEFF Research Database (Denmark)

    Rasmussen, Lone B; Kirkegaard-Klitbo, Ditte Marie; Laurberg, Peter

    2016-01-01

    according to grade. The UIC was higher in children than in adults from the same area. CONCLUSIONS: The iodine excretion among schoolchildren in Copenhagen, an area with a relatively high iodine content in tap water, was within the recommended range as assessed by the UIC. An increased iodine fortification......INTRODUCTION: Studies of dietary habits show a high iodine intake in children in Denmark. Iodine excretion in children has not previously been assessed. Iodine excretion in adults is below the recommended threshold, and it is therefore being discussed to increase the fortification level. The main...... will not have negative consequences for this group. FUNDING: The Ministry of Food, Agriculture and Fisheries. TRIAL REGISTRATION: not relevant....

  17. Iodine chemistry in a reactor regulation

    Energy Technology Data Exchange (ETDEWEB)

    Powers, D.A. [Nuclear Regulatory Commission, Washington, DC (United States). Advisory Committee on Reactor Safeguards

    1996-12-01

    Radioactive iodine has always been an important consideration in the regulation of nuclear power reactors to assure the health and safety of the public. Regulators adopted conservatively bounding predictions of iodine behavior in the earliest days of the development of nuclear power because there was so little known about either accidents or the chemistry of iodine. Today there is a flood of new information and understanding of the chemistry of iodine under reactor accident conditions. This paper offers some thoughts on how the community of scientists engaged in the study of iodine chemistry can present the results of their work so that it is more immediately adopted by the regulator. It is suggested that the scientific community consider the concept of consensus standards so effectively used within the engineering community to define the status of the study of radioactive iodine chemistry for reactor safety. (author) 9 refs.

  18. Site of iodination in rat mammary gland

    Energy Technology Data Exchange (ETDEWEB)

    Strum, J.M.

    1978-10-01

    The ability of the mammary gland to take up and organically bind radioiodide was studied in non-pregnant, pregnant, and lactating rats. Autoradiography was used to determine whether duct cells or alveolar cells are responsible for iodination in the rat mammary gland. Iodination was not detected in mammary glands from non-pregnant rats, but occurred late in the twelfth day of gestation and continued throughout pregnancy and lactation. Protein-containing vacuoles in alveolar cells and casein-like proteins in milk were the major sites where iodination occurred within the gland. Milk proteins in the lumens of ductules adjacent to alveoli were also iodinated. In contrast, ducts, myoepithelial cells, fat cells, blood vessels and other histological components of the gland did not show iodinating capability. Cytochemistry was also used to identify endogenous mammary peroxidase activity in the same glands, and it was found that the presence and location of this enzyme were correlated with the ability to iodinate.

  19. Structured Additive Regression Models: An R Interface to BayesX

    Directory of Open Access Journals (Sweden)

    Nikolaus Umlauf

    2015-02-01

    Full Text Available Structured additive regression (STAR models provide a flexible framework for model- ing possible nonlinear effects of covariates: They contain the well established frameworks of generalized linear models and generalized additive models as special cases but also allow a wider class of effects, e.g., for geographical or spatio-temporal data, allowing for specification of complex and realistic models. BayesX is standalone software package providing software for fitting general class of STAR models. Based on a comprehensive open-source regression toolbox written in C++, BayesX uses Bayesian inference for estimating STAR models based on Markov chain Monte Carlo simulation techniques, a mixed model representation of STAR models, or stepwise regression techniques combining penalized least squares estimation with model selection. BayesX not only covers models for responses from univariate exponential families, but also models from less-standard regression situations such as models for multi-categorical responses with either ordered or unordered categories, continuous time survival data, or continuous time multi-state models. This paper presents a new fully interactive R interface to BayesX: the R package R2BayesX. With the new package, STAR models can be conveniently specified using Rs formula language (with some extended terms, fitted using the BayesX binary, represented in R with objects of suitable classes, and finally printed/summarized/plotted. This makes BayesX much more accessible to users familiar with R and adds extensive graphics capabilities for visualizing fitted STAR models. Furthermore, R2BayesX complements the already impressive capabilities for semiparametric regression in R by a comprehensive toolbox comprising in particular more complex response types and alternative inferential procedures such as simulation-based Bayesian inference.

  20. Glass composite waste forms for iodine confined in bismuth-embedded SBA-15

    Science.gov (United States)

    Yang, Jae Hwan; Park, Hwan Seo; Ahn, Do-Hee; Yim, Man-Sung

    2016-11-01

    The aim of this study was to stabilize bismuth-embedded SBA-15 that captured iodine gas by fabrication of monolithic waste forms. The iodine containing waste was mixed with Bi2O3 (a stabilizing additive) and low-temperature sintering glass followed by pelletizing and the sintering process to produce glass composite materials. Iodine volatility during the sintering process was significantly affected by the ratio of Bi2O3 and the glass composition. It was confirmed that BiI3, the main iodine phase within bismuth-embedded SBA-15, was effectively transformed to the mixed phases of Bi5O7I and BiOI. The initial leaching rates of iodine from the glass composite waste forms ranged 10-3-10-2 g/m2 day, showing the stability of the iodine phases encapsulated by the glassy networks. It was also observed that common groundwater anions (e.g., chloride, carbonate, sulfite, and fluoride) elevated the iodine leaching rate by anion exchange reactions. The present results suggest that the glass composite waste form of bismuth-embedded SBA-15 could be a candidate material for stable storage of 129I.

  1. Iodine Absorption Cells Purity Testing

    Directory of Open Access Journals (Sweden)

    Jan Hrabina

    2017-01-01

    Full Text Available This article deals with the evaluation of the chemical purity of iodine-filled absorption cells and the optical frequency references used for the frequency locking of laser standards. We summarize the recent trends and progress in absorption cell technology and we focus on methods for iodine cell purity testing. We compare two independent experimental systems based on the laser-induced fluorescence method, showing an improvement of measurement uncertainty by introducing a compensation system reducing unwanted influences. We show the advantages of this technique, which is relatively simple and does not require extensive hardware equipment. As an alternative to the traditionally used methods we propose an approach of hyperfine transitions’ spectral linewidth measurement. The key characteristic of this method is demonstrated on a set of testing iodine cells. The relationship between laser-induced fluorescence and transition linewidth methods will be presented as well as a summary of the advantages and disadvantages of the proposed technique (in comparison with traditional measurement approaches.

  2. A guide to generalized additive models in crop science using SAS and R

    Directory of Open Access Journals (Sweden)

    Josefine Liew

    2015-06-01

    Full Text Available Linear models and generalized linear models are well known and are used extensively in crop science. Generalized additive models (GAMs are less well known. GAMs extend generalized linear models through inclusion of smoothing functions of explanatory variables, e.g., spline functions, allowing the curves to bend to better describe the observed data. This article provides an introduction to GAMs in the context of crop science experiments. This is exemplified using a dataset consisting of four populations of perennial sow-thistle (Sonchus arvensis L., originating from two regions, for which emergence of shoots over time was compared.

  3. Iodine: It's Important in Patients that Require Parenteral Nutrition

    NARCIS (Netherlands)

    Zimmermann, M.B.

    2009-01-01

    Iodine deficiency has multiple adverse effects on growth and development because of inadequate thyroid hormone production. Four methods are generally recommended for assessment of iodine nutrition: urinary iodine concentration, thyroid size, and blood concentrations of thyroid-stimulating hormone an

  4. Iodine Deficiency Disorders (IDD) in Burie and Womberma Districts ...

    African Journals Online (AJOL)

    Recent findings show that both endemic and non-endemic areas have high goiter ... iodine level and concentration of iodized salt is dietary iodine deficiency. ... on adverse effects of IDD and benefits of iodine nutrition is highly recommended.

  5. Iodine deficiency in pregnancy in Denmark. Regional variations and frequency of individual iodine supplementation

    DEFF Research Database (Denmark)

    Nøhr, S B; Laurberg, P; Børlum, K G

    1993-01-01

    Iodine requirements are increased during pregnancy and lactation and adequate iodine intake is important for normal brain development of the fetus/newborn child. The aim of the present study was to evaluate the extent to which this increase in iodine requirement is met in pregnant women living in...

  6. Iodine deficiency in pregnancy and the effects of maternal iodine supplementation on the offspring: a review

    NARCIS (Netherlands)

    Zimmermann, M.B.

    2009-01-01

    The World Health Organization (WHO) recently increased their recommended iodine intake during pregnancy from 200 to 250 µg/d and suggested that a median urinary iodine (UI) concentration of 150-249 µg/L indicates adequate iodine intake in pregnant women. Thyrotropin concentrations in blood collected

  7. Iodine deficiency in pregnancy and the effects of maternal iodine supplementation on the offspring: a review

    NARCIS (Netherlands)

    Zimmermann, M.B.

    2009-01-01

    The World Health Organization (WHO) recently increased their recommended iodine intake during pregnancy from 200 to 250 µg/d and suggested that a median urinary iodine (UI) concentration of 150-249 µg/L indicates adequate iodine intake in pregnant women. Thyrotropin concentrations in blood collected

  8. Iodine requirements and the risks and benefits of correcting iodine deficiency in populations

    NARCIS (Netherlands)

    Zimmermann, M.B.

    2008-01-01

    Iodine deficiency has multiple adverse effects on growth and development due to inadequate thyroid hormone production that are termed the iodine deficiency disorders (IDD). IDD remains the most common cause of preventable mental impairment worldwide. IDD assessment methods include urinary iodine con

  9. Modal analysis of additive manufactured carbon fiber reinforced polymer composite framework: Experiment and modeling

    Science.gov (United States)

    Dryginin, N. V.; Krasnoveikin, V. A.; Filippov, A. V.; Tarasov, S. Yu.; Rubtsov, V. E.

    2016-11-01

    Additive manufacturing by 3D printing is the most advanced and promising trend for making the multicomponent composites. Polymer-based carbon fiber reinforced composites demonstrate high mechanical properties combined with low weight characteristics of the component. This paper shows the results of 3D modeling and experimental modal analysis on a polymer composite framework obtained using additive manufacturing. By the example of three oscillation modes it was shown the agreement between the results of modeling and experimental modal analysis with the use of laser Doppler vibrometry.

  10. Asymptotics on Semiparametric Analysis of Multivariate Failure Time Data Under the Additive Hazards Model

    Institute of Scientific and Technical Information of China (English)

    Huan-bin Liu; Liu-quan Sun; Li-xing Zhu

    2005-01-01

    Many survival studies record the times to two or more distinct failures on each subject. The failures may be events of different natures or may be repetitions of the same kind of event. In this article, we consider the regression analysis of such multivariate failure time data under the additive hazards model. Simple weighted estimating functions for the regression parameters are proposed, and asymptotic distribution theory of the resulting estimators are derived. In addition, a class of generalized Wald and generalized score statistics for hypothesis testing and model selection are presented, and the asymptotic properties of these statistics are examined.

  11. Discriminative accuracy of genomic profiling comparing multiplicative and additive risk models.

    Science.gov (United States)

    Moonesinghe, Ramal; Khoury, Muin J; Liu, Tiebin; Janssens, A Cecile J W

    2011-02-01

    Genetic prediction of common diseases is based on testing multiple genetic variants with weak effect sizes. Standard logistic regression and Cox Proportional Hazard models that assess the combined effect of multiple variants on disease risk assume multiplicative joint effects of the variants, but this assumption may not be correct. The risk model chosen may affect the predictive accuracy of genomic profiling. We investigated the discriminative accuracy of genomic profiling by comparing additive and multiplicative risk models. We examined genomic profiles of 40 variants with genotype frequencies varying from 0.1 to 0.4 and relative risks varying from 1.1 to 1.5 in separate scenarios assuming a disease risk of 10%. The discriminative accuracy was evaluated by the area under the receiver operating characteristic curve. Predicted risks were more extreme at the lower and higher risks for the multiplicative risk model compared with the additive model. The discriminative accuracy was consistently higher for multiplicative risk models than for additive risk models. The differences in discriminative accuracy were negligible when the effect sizes were small (risk genotypes were common or when they had stronger effects. Unraveling the exact mode of biological interaction is important when effect sizes of genetic variants are moderate at the least, to prevent the incorrect estimation of risks.

  12. Discrepancies between iodine and technetium thyroid scintigraphy

    Energy Technology Data Exchange (ETDEWEB)

    Barth, J.D.; Bakker, W.H.; Henneman, G.

    1978-08-04

    For routine thyroid scanning, the sodium pertechnetate Tc-99m scan is preferred over sodium iodide I-131 scanning in many laboratories. Radiation safety for the patient and reduction of costs are the primary reasons for this. Discrepancies can occur between iodine scans (iodine I-123 and /sup 131/I) as compared with /sup 99m/Tc scans: e.g., a nodule appearing cold on an iodine scan may be warm with a /sup 99m/Tc scan. To give other examples of discrepancies that can occur when /sup 99m/Tc is compared with iodine, we present two cases.

  13. Breast Milk Iodine and Iodine Status of Breast-Fed Infants

    Directory of Open Access Journals (Sweden)

    Golam Morshed Molla

    2015-07-01

    Full Text Available Background: Breast milk is the only source of iodine for exclusively breast-fed infants. Iodine status of breast-fed infants depends on iodine in breast milk and also number of feeding in 24 hours. Iodine deficiency and iodine excess both have bad impact on infant’s health. Objective: To measure the iodine in breast milk and to evaluate iodine status of their breast-fed infants. Materials and method: This observational analytical study was carried out in the department of Biochemistry, Bangabandhu Sheikh Mujib Medical University, Dhaka with active cooperation of Kumudini Women’s Medical College Hospital, Mirzapur, Tangail involving fifty lactating mothers and their exclusively breast-fed infants. Early morning urine and breast milk samples were collected in dry and clean plastic container free from any chemical contamination. Urinary iodine was used as indicator for assessing iodine status. All statistical analyses were done by using SPSS (statistical programme for social science 12 version software package for Windows. Results: The median (range urinary iodine concentration of lactating mothers and their breast-fed infants were 225.25 μg/L (61.50-530.00 and 225.75 μg/L (100.50-526.00 respectively. The median (range breast-milk iodine concentration was 157 μg/L (54.50-431.50 which was more than three times of recommended minimum concentration (50 μg/L. Only 2 (4% lactating mothers had mild biochemical iodine deficiency (UIE, 50-99 μg/L. There was no biochemical iodine deficiency of breast-fed infants. Iodine in breast milk of lactating mothers was positively correlated with their urinary iodine excretion (p<0.01. Infant’s urinary iodine was positively correlated with iodine concentration in breast milk (p<0.01 and with urinary iodine of lactating mothers (p<0.01. Conclusion: Lactating mothers and their breast-fed infants in this study were iodine sufficient. If iodine content of breast-milk is within normal range, 10-12 numbers of

  14. Integrated reservoir characterization: Improvement in heterogeneities stochastic modelling by integration of additional external constraints

    Energy Technology Data Exchange (ETDEWEB)

    Doligez, B.; Eschard, R. [Institut Francais du Petrole, Rueil Malmaison (France); Geffroy, F. [Centre de Geostatistique, Fontainebleau (France)] [and others

    1997-08-01

    The classical approach to construct reservoir models is to start with a fine scale geological model which is informed with petrophysical properties. Then scaling-up techniques allow to obtain a reservoir model which is compatible with the fluid flow simulators. Geostatistical modelling techniques are widely used to build the geological models before scaling-up. These methods provide equiprobable images of the area under investigation, which honor the well data, and which variability is the same than the variability computed from the data. At an appraisal phase, when few data are available, or when the wells are insufficient to describe all the heterogeneities and the behavior of the field, additional constraints are needed to obtain a more realistic geological model. For example, seismic data or stratigraphic models can provide average reservoir information with an excellent areal coverage, but with a poor vertical resolution. New advances in modelisation techniques allow now to integrate this type of additional external information in order to constrain the simulations. In particular, 2D or 3D seismic derived information grids, or sand-shale ratios maps coming from stratigraphic models can be used as external drifts to compute the geological image of the reservoir at the fine scale. Examples are presented to illustrate the use of these new tools, their impact on the final reservoir model, and their sensitivity to some key parameters.

  15. Estimation of additive and dominance variance for reproductive traits from different models in Duroc purebred

    Directory of Open Access Journals (Sweden)

    Talerngsak Angkuraseranee

    2010-05-01

    Full Text Available The additive and dominance genetic variances of 5,801 Duroc reproductive and growth records were estimated usingBULPF90 PC-PACK. Estimates were obtained for number born alive (NBA, birth weight (BW, number weaned (NW, andweaning weight (WW. Data were analyzed using two mixed model equations. The first model included fixed effects andrandom effects identifying inbreeding depression, additive gene effect and permanent environments effects. The secondmodel was similar to the first model, but included the dominance genotypic effect. Heritability estimates of NBA, BW, NWand WW from the two models were 0.1558/0.1716, 0.1616/0.1737, 0.0372/0.0874 and 0.1584/0.1516 respectively. Proportionsof dominance effect to total phenotypic variance from the dominance model were 0.1024, 0.1625, 0.0470, and 0.1536 for NBA,BW, NW and WW respectively. Dominance effects were found to have sizable influence on the litter size traits analyzed.Therefore, genetic evaluation with the dominance model (Model 2 is found more appropriate than the animal model (Model 1.

  16. New results in RR Lyrae modeling: convective cycles, additional modes and more

    CERN Document Server

    Molnár, L; Szabó, R; Plachy, E

    2012-01-01

    Recent theoretical and observational findings breathed new life into the field of RR Lyrae stars. The ever more precise and complete measurements of the space asteroseismology missions revealed new details, such as the period doubling and the presence of the additional modes in the stars. Theoretical work also flourished: period doubling was explained and an additional mode has been detected in hydrodynamic models as well. Although the most intriguing mystery, the Blazhko-effect has remained unsolved, new findings indicate that the convective cycle model can be effectively ruled out for short- and medium-period modulations. On the other hand, the plausibility of the radial resonance model is increasing, as more and more resonances are detected both in models and stars.

  17. Analysis of error-prone survival data under additive hazards models: measurement error effects and adjustments.

    Science.gov (United States)

    Yan, Ying; Yi, Grace Y

    2016-07-01

    Covariate measurement error occurs commonly in survival analysis. Under the proportional hazards model, measurement error effects have been well studied, and various inference methods have been developed to correct for error effects under such a model. In contrast, error-contaminated survival data under the additive hazards model have received relatively less attention. In this paper, we investigate this problem by exploring measurement error effects on parameter estimation and the change of the hazard function. New insights of measurement error effects are revealed, as opposed to well-documented results for the Cox proportional hazards model. We propose a class of bias correction estimators that embraces certain existing estimators as special cases. In addition, we exploit the regression calibration method to reduce measurement error effects. Theoretical results for the developed methods are established, and numerical assessments are conducted to illustrate the finite sample performance of our methods.

  18. [download] (1035Coordinate Descent Methods for the Penalized Semiparametric Additive Hazards Model

    Directory of Open Access Journals (Sweden)

    Anders Gorst-Rasmussen

    2012-04-01

    Full Text Available For survival data with a large number of explanatory variables, lasso penalized Cox regression is a popular regularization strategy. However, a penalized Cox model may not always provide the best fit to data and can be difficult to estimate in high dimension because of its intrinsic nonlinearity. The semiparametric additive hazards model is a flexible alternative which is a natural survival analogue of the standard linear regression model. Building on this analogy, we develop a cyclic coordinate descent algorithm for fitting the lasso and elastic net penalized additive hazards model. The algorithm requires no nonlinear optimization steps and offers excellent performance and stability. An implementation is available in the R package ahaz. We demonstrate this implementation in a small timing study and in an application to real data.

  19. Nonparametric Independence Screening in Sparse Ultra-High Dimensional Additive Models

    CERN Document Server

    Fan, Jianqing; Song, Rui

    2011-01-01

    A variable screening procedure via correlation learning was proposed Fan and Lv (2008) to reduce dimensionality in sparse ultra-high dimensional models. Even when the true model is linear, the marginal regression can be highly nonlinear. To address this issue, we further extend the correlation learning to marginal nonparametric learning. Our nonparametric independence screening is called NIS, a specific member of the sure independence screening. Several closely related variable screening procedures are proposed. Under the nonparametric additive models, it is shown that under some mild technical conditions, the proposed independence screening methods enjoy a sure screening property. The extent to which the dimensionality can be reduced by independence screening is also explicitly quantified. As a methodological extension, an iterative nonparametric independence screening (INIS) is also proposed to enhance the finite sample performance for fitting sparse additive models. The simulation results and a real data a...

  20. Experimental results of an iodine plasma in PEGASES gridded thruster

    Science.gov (United States)

    Grondein, Pascaline; Aanesland, Ane

    2015-09-01

    In the electric gridded thruster PEGASES, both positive and negative ions are expelled after extraction from an ion-ion plasma. This ion-ion plasma is formed downstream a localized magnetic field placed a few centimeters from the ionization region, trapping and cooling down the electron to allow a better attachment to an electronegative gas. For this thruster concept, iodine has emerged as the most attractive option. Heavy, under diatomic form and therefore good for high thrust, its low ionization threshold and high electronegativity lead to high ion-ion densities and low RF power. After the proof-of-concept of PEGASES using SF6 as propellant, we present here experimental results of an iodine plasma studied inside PEGASES thruster. At solid state at standard temperature and pressure, iodine is heated to sublimate, then injected inside the chamber where the neutral gas is heated and ionized. The whole injection system is heated to avoid deposition on surfaces and a mass flow controller allows a fine control on the neutral gas mass flow. A 3D translation stage inside the vacuum chamber allows volumetric plasma studies using electrostatic probes. The results are also compared with the global model dedicated to iodine as propellant for electric gridded thrusters. This work has been done within the LABEX Plas@par project, and received financial state aid managed by the Agence Nationale de la Recherche, as part of the programme ``Investissements d'avenir.''

  1. Dietary iodine deficiency in the Gippsland region of Victoria, Australia

    OpenAIRE

    Rahman, Mohammad Ashequr

    2017-01-01

    Background Iodine is an essential micronutrient for the production of thyroid hormones and normal neurodevelopment. A deficiency in iodine causes a number of defects collectively known as Iodine Deficiency Disorder (IDD). Even mild iodine deficiency in pregnancy is a risk factor for babies as it may result in impaired intellectual development; this is the most serious consequence of mild to moderate dietary iodine deficiency. Australia overall is iodine deficient. However, in the Nationa...

  2. Iodine uptake and distribution in horticultural and fruit tree species

    OpenAIRE

    Alessandra Caffagni; Nicola Pecchioni; Pierluigi Meriggi; Valerio Bucci; Emidio Sabatini; Nazareno Acciarri; Tommaso Ciriaci; Laura Pulcini; Nazzareno Felicioni; Massimiliano Beretta; Justyna Milc

    2012-01-01

    Iodine is an essential microelement for humans and iodine deficiency disorder (IDD) is one of the most widespread nutrient-deficiency diseases in the world. Iodine biofortification of plants provides an attractive opportunity to increase iodine intake in humans and to prevent and control IDD. This study was conducted to investigate the iodine uptake and accumulation in edible portion of two fruit trees: plum and nectarine, and two horticultural crops: tomato and potato. Two type of iodine tre...

  3.  The additive hazards model with high-dimensional regressors

    DEFF Research Database (Denmark)

    Martinussen, Torben

    2009-01-01

    This paper considers estimation and prediction in the Aalen additive hazards model in the case where the covariate vector is high-dimensional such as gene expression measurements. Some form of dimension reduction of the covariate space is needed to obtain useful statistical analyses. We study the...... model. A standard PLS algorithm can also be constructed, but it turns out that the resulting predictor can only be related to the original covariates via time-dependent coefficients...

  4. French approach for the distribution of iodine tablets in the vicinity of nuclear power plants.

    Science.gov (United States)

    Le Guen, B; Hémidy, P Y; Garcier, Y

    2002-08-01

    In the event of an accident, isotopes of iodine including 131I can be released into the atmosphere. In 1997, as a safety measure, the French government decided to begin the distribution of stable iodine tablets in advance, directly to those living in the vicinity of the nuclear power plants, to avoid having to do so in an emergency. The tablets were previously stored by Electricite de France (EDF), which held them at the disposal of the government authorities. This year, as the existing tablets pass their use--by date, EDF has begun redistributing stable iodine within a ten-kilometer radius around its nineteen nuclear sites. We review the effectiveness of this countermeasure as well as the nature and incidence of possible side effects while measuring the duration of its action under the conditions in which it was administered. A bibliographic study of the kinetics of iodine in the human body has enabled the indications and the means of use to be determined. The effectiveness of the preventive effect and the onset of thyroid dysfunction depends on both external and individual factors: uptake of iodine from food, functional condition of the thyroid, and age. In an individual with a healthy thyroid, taking 100 mg of stable iodine immediately before exposure to radioactive iodine reduces the dose to the thyroid by at least 95%. In cases of prolonged exposure, the reduction is smaller. Therefore, if exposure lasts for a number of days, consideration needs to be given to taking stable iodine again, to maintain maximum protection. In addition to the bibliographic study, this presentation covers the impact of making iodine available and the action taken to educate the public; the attitudes of populations concerned; and the reaction of the health professionals.

  5. Experimental model and analytic solution for real-time observation of vehicle's additional steer angle

    Science.gov (United States)

    Zhang, Xiaolong; Li, Liang; Pan, Deng; Cao, Chengmao; Song, Jian

    2014-03-01

    The current research of real-time observation for vehicle roll steer angle and compliance steer angle(both of them comprehensively referred as the additional steer angle in this paper) mainly employs the linear vehicle dynamic model, in which only the lateral acceleration of vehicle body is considered. The observation accuracy resorting to this method cannot meet the requirements of vehicle real-time stability control, especially under extreme driving conditions. The paper explores the solution resorting to experimental method. Firstly, a multi-body dynamic model of a passenger car is built based on the ADAMS/Car software, whose dynamic accuracy is verified by the same vehicle's roadway test data of steady static circular test. Based on this simulation platform, several influencing factors of additional steer angle under different driving conditions are quantitatively analyzed. Then ɛ-SVR algorithm is employed to build the additional steer angle prediction model, whose input vectors mainly include the sensor information of standard electronic stability control system(ESC). The method of typical slalom tests and FMVSS 126 tests are adopted to make simulation, train model and test model's generalization performance. The test result shows that the influence of lateral acceleration on additional steer angle is maximal (the magnitude up to 1°), followed by the longitudinal acceleration-deceleration and the road wave amplitude (the magnitude up to 0.3°). Moreover, both the prediction accuracy and the calculation real-time of the model can meet the control requirements of ESC. This research expands the accurate observation methods of the additional steer angle under extreme driving conditions.

  6. Stakeholder reactions toward iodine biofortified foods. An application of protection motivation theory.

    Science.gov (United States)

    De Steur, Hans; Mogendi, Joseph Birundu; Wesana, Joshua; Makokha, Anselimo; Gellynck, Xavier

    2015-09-01

    To use Protection Motivation Theory (PMT) to evaluate stakeholders' intention to adopt iodine biofortified foods as an alternative means to improve children's iodine status and overall school performance. A survey was administered with 360 parents of primary school children and 40 school heads. Protection motivation is measured through matching the cognitive processes they use to evaluate iodine deficiency (threat appraisal), as well as iodine biofortified foods to reduce the threat (coping appraisal). Data were analyzed through Robust (Cluster) regression analysis. Gender had a significant effect on coping appraisal for school heads, while age, education, occupation, income, household size and knowledge were significant predictors of threat, coping appraisal and/or protection motivation intention among parents. Nevertheless, in the overall protection motivation model, only two coping factors, namely self-efficacy (parents) and response cost (school heads), influenced the intention to adopt iodine biofortified foods. School feeding programs incorporating iodine biofortification should strive to increase not only consumer knowledge about iodine but also its association to apparent deficiency disorders, boost self-efficacy and ensure that the costs incurred are not perceived as barriers of adoption. The insignificant threat appraisal effects lend support for targeting future communication on biofortification upon the strategies itself, rather than on the targeted micronutrient deficiency. PMT, and coping factors in particular, seem to be valuable in assessing intentions to adopt healthy foods. Nevertheless, research is needed to improve the impacts of threat appraisal factors. Copyright © 2015 Elsevier Ltd. All rights reserved.

  7. A Negative Feedback Between Anthropogenic Ozone Pollution and Enhanced Ocean Emissions of Iodine

    Science.gov (United States)

    Saiz-Lopez, A.; Prados-Roman, C.; Cuevas, C.; Fernandez, R.; Lamarque, J. F.; Kinnison, D. E.

    2014-12-01

    Naturally emitted from the oceans, iodine compounds efficiently destroy atmospheric ozone and reduce its positive radiative forcing effects in the troposphere. Emissions of inorganic iodine have been experimentally shown to depend on the deposition to the oceans of tropospheric ozone, whose concentrations have significantly increased since 1850 as a result of human activities. A chemistry-climate model is used to quantify the current ocean emissions of inorganic iodine and assess the impact that the anthropogenic increase of tropospheric ozone has had on the natural cycle of iodine in the marine environment since pre-industrial times. Results included in this communication indicate that the human-driven enhancement of tropospheric ozone has doubled the oceanic inorganic iodine emissions following the reaction of ozone with iodide at the sea surface. The consequent build-up of atmospheric iodine, with maximum enhancements of up to 70% with respect to preindustrial times in continental pollution outflow regions, has in turn accelerated the ozone chemical loss over the oceans with strong spatial patterns. We suggest that this ocean-atmosphere interaction represents a negative geochemical feedback loop by which current ocean emissions of iodine act as a natural buffer for ozone pollution and its radiative forcing in the global marine environment.

  8. Changing dynamics: Time-varying autoregressive models using generalized additive modeling.

    Science.gov (United States)

    Bringmann, Laura F; Hamaker, Ellen L; Vigo, Daniel E; Aubert, André; Borsboom, Denny; Tuerlinckx, Francis

    2017-09-01

    In psychology, the use of intensive longitudinal data has steeply increased during the past decade. As a result, studying temporal dependencies in such data with autoregressive modeling is becoming common practice. However, standard autoregressive models are often suboptimal as they assume that parameters are time-invariant. This is problematic if changing dynamics (e.g., changes in the temporal dependency of a process) govern the time series. Often a change in the process, such as emotional well-being during therapy, is the very reason why it is interesting and important to study psychological dynamics. As a result, there is a need for an easily applicable method for studying such nonstationary processes that result from changing dynamics. In this article we present such a tool: the semiparametric TV-AR model. We show with a simulation study and an empirical application that the TV-AR model can approximate nonstationary processes well if there are at least 100 time points available and no unknown abrupt changes in the data. Notably, no prior knowledge of the processes that drive change in the dynamic structure is necessary. We conclude that the TV-AR model has significant potential for studying changing dynamics in psychology. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  9. Urinary iodine, thyroid function, and thyroglobulin as biomarkers of iodine status.

    Science.gov (United States)

    Pearce, Elizabeth N; Caldwell, Kathleen L

    2016-09-01

    The accurate assessment of population iodine status is necessary to inform public health policies and clinical research on iodine nutrition, particularly the role of iodine adequacy in normal neurodevelopment. Urinary iodine concentration (UIC) directly reflects dietary iodine intake and is the most common indicator used worldwide to assess population iodine status. The CDC established the Ensuring the Quality of Iodine Procedures program in 2001 to provide laboratories that measure urinary iodine with an independent assessment of their analytic performance; this program fosters improvement in the assessment of UIC. Clinical laboratory tests of thyroid function (including serum concentrations of the pituitary hormone thyrotropin and the thyroid hormones thyroxine and triiodothyronine) are sometimes used as indicators of iodine status, although such use is often problematic. Even in severely iodine-deficient regions, there is a great deal of intraindividual variation in the ability of the thyroid to adapt. In most settings and in most population subgroups other than newborns, thyroid function tests are not considered sensitive indicators of population iodine status. However, the thyroid-derived protein thyroglobulin is increasingly being used for this purpose. Thyroglobulin can be measured in either serum or dried blood spot (DBS) samples. The use of DBS samples is advantageous in resource-poor regions. Improved methodologies for ascertaining maternal iodine status are needed to facilitate research on developmental correlates of iodine status. Thyroglobulin may prove to be a useful biomarker for both maternal and neonatal iodine status, but validated assay-specific reference ranges are needed for the determination of iodine sufficiency in both pregnant women and neonates, and trimester-specific ranges are possibly needed for pregnant women. UIC is currently a well-validated population biomarker, but individual biomarkers that could be used for research, patient care

  10. Amniotic fluid iodine concentrations do not vary in pregnant women with varying iodine intake.

    Science.gov (United States)

    García-Fuentes, Eduardo; Gallo, Manuel; García, Laureano; Prieto, Stephanie; Alcaide-Torres, Javier; Santiago, Piedad; Velasco, Inés; Soriguer, Federico

    2008-06-01

    Iodine deficiency is an important clinical and public health problem. Its prevention begins with an adequate intake of iodine during pregnancy. International agencies recommend at least 200 microg iodine per d for pregnant women. We assessed whether iodine concentrations in the amniotic fluid of healthy pregnant women are independent of iodine intake. This cross-sectional, non-interventional study included 365 consecutive women who underwent amniocentesis to determine the fetal karyotype. The amniocentesis was performed with abdominal antisepsis using chlorhexidine. The iodine concentration was measured in urine and amniotic fluid. The study variables were the intake of iodized salt and multivitamin supplements or the prescription of a KI supplement. The mean level of urinary iodine was 139.0 (SD 94.5) microg/l and of amniotic fluid 15.81 (SD 7.09) microg/l. The women who consumed iodized salt and those who took a KI supplement had significantly higher levels of urinary iodine than those who did not (P = 0.01 and P = 0.004, respectively). The urinary iodine levels were not significantly different in the women who took a multivitamin supplement compared with those who did not take this supplement, independently of iodine concentration or multivitamin supplement. The concentrations of iodine in the amniotic fluid were similar, independent of the dietary iodine intake. Urine and amniotic fluid iodine concentrations were weakly correlated, although the amniotic fluid values were no higher in those women taking a KI supplement. KI prescription at recommended doses increases the iodine levels in the mother without influencing the iodine levels in the amniotic fluid.

  11. Vector generalized linear and additive models with an implementation in R

    CERN Document Server

    Yee, Thomas W

    2015-01-01

    This book presents a statistical framework that expands generalized linear models (GLMs) for regression modelling. The framework shared in this book allows analyses based on many semi-traditional applied statistics models to be performed as a coherent whole. This is possible through the approximately half-a-dozen major classes of statistical models included in the book and the software infrastructure component, which makes the models easily operable.    The book’s methodology and accompanying software (the extensive VGAM R package) are directed at these limitations, and this is the first time the methodology and software are covered comprehensively in one volume. Since their advent in 1972, GLMs have unified important distributions under a single umbrella with enormous implications. The demands of practical data analysis, however, require a flexibility that GLMs do not have. Data-driven GLMs, in the form of generalized additive models (GAMs), are also largely confined to the exponential family. This book ...

  12. Representational Flexibility and Problem-Solving Ability in Fraction and Decimal Number Addition: A Structural Model

    Science.gov (United States)

    Deliyianni, Eleni; Gagatsis, Athanasios; Elia, Iliada; Panaoura, Areti

    2016-01-01

    The aim of this study was to propose and validate a structural model in fraction and decimal number addition, which is founded primarily on a synthesis of major theoretical approaches in the field of representations in Mathematics and also on previous research on the learning of fractions and decimals. The study was conducted among 1,701 primary…

  13. Modeling the use of sulfate additives for potassium chloride destruction in biomass combustion

    DEFF Research Database (Denmark)

    Wu, Hao; Grell, Morten Nedergaard; Jespersen, Jacob Boll;

    2013-01-01

    was affected by the decomposition temperature. Based on the experimental data, a model was proposed to simulate the sulfation of KCl by different sulfate addition, and the simulation results were compared with pilot-scale experiments conducted in a bubbling fluidized bed reactor. The simulation results...

  14. Parametrically Guided Generalized Additive Models with Application to Mergers and Acquisitions Data.

    Science.gov (United States)

    Fan, Jianqing; Maity, Arnab; Wang, Yihui; Wu, Yichao

    2013-01-01

    Generalized nonparametric additive models present a flexible way to evaluate the effects of several covariates on a general outcome of interest via a link function. In this modeling framework, one assumes that the effect of each of the covariates is nonparametric and additive. However, in practice, often there is prior information available about the shape of the regression functions, possibly from pilot studies or exploratory analysis. In this paper, we consider such situations and propose an estimation procedure where the prior information is used as a parametric guide to fit the additive model. Specifically, we first posit a parametric family for each of the regression functions using the prior information (parametric guides). After removing these parametric trends, we then estimate the remainder of the nonparametric functions using a nonparametric generalized additive model, and form the final estimates by adding back the parametric trend. We investigate the asymptotic properties of the estimates and show that when a good guide is chosen, the asymptotic variance of the estimates can be reduced significantly while keeping the asymptotic variance same as the unguided estimator. We observe the performance of our method via a simulation study and demonstrate our method by applying to a real data set on mergers and acquisitions.

  15. Representational Flexibility and Problem-Solving Ability in Fraction and Decimal Number Addition: A Structural Model

    Science.gov (United States)

    Deliyianni, Eleni; Gagatsis, Athanasios; Elia, Iliada; Panaoura, Areti

    2016-01-01

    The aim of this study was to propose and validate a structural model in fraction and decimal number addition, which is founded primarily on a synthesis of major theoretical approaches in the field of representations in Mathematics and also on previous research on the learning of fractions and decimals. The study was conducted among 1,701 primary…

  16. Midrapidity inclusive densities in high energy pp collisions in additive quark model

    Science.gov (United States)

    Shabelski, Yu. M.; Shuvaev, A. G.

    2016-08-01

    High energy (CERN SPS and LHC) inelastic pp (pbar{p}) scattering is treated in the framework of the additive quark model together with Pomeron exchange theory. We extract the midrapidity inclusive density of the charged secondaries produced in a single quark-quark collision and investigate its energy dependence. Predictions for the π p collisions are presented.

  17. Additional interfacial force in lattice Boltzmann models for incompressible multiphase flows

    CERN Document Server

    Li, Q; Gao, Y J

    2011-01-01

    The existing lattice Boltzmann models for incompressible multiphase flows are mostly constructed with two distribution functions, one is the order parameter distribution function, which is used to track the interface between different phases, and the other is the pressure distribution function for solving the velocity field. In this brief report, it is shown that in these models the recovered momentum equation is inconsistent with the target one: an additional interfacial force is included in the recovered momentum equation. The effects of the additional force are investigated by numerical simulations of droplet splashing on a thin liquid film and falling droplet under gravity. In the former test, it is found that the formation and evolution of secondary droplets are greatly affected, while in the latter the additional force is found to increase the falling velocity and limit the stretch of the droplet.

  18. Modeling and Simulation of the Sulfur-Iodine Process Coupled to a Very High-Temperature Gas-Cooled Nuclear Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Shin, Youngjoon; Lee, Taehoon; Lee, Kiyoung; Kim, Minhwan [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2015-10-15

    Hydrogen produced from water using nuclear energy will avoid both the use of fossil fuel and CO{sub 2} emission presumed to be the dominant reason for global warming. A thermo-chemical sulfur-iodine (SI) process coupled to a Very High Temperature Gas-Cooled Reactor(VHTR) is one of the most prospective hydrogen production methods that split water using nuclear energy because the SI process is suitable for large-scale hydrogen production without CO{sub 2} emission. The dynamic simulation code to evaluate the start-up behavior of the chemical reactors placed on the secondary helium loop of the SI process has been developed and partially verified using the steady state values obtained from the Aspen Plus{sup TM} Code simulation. As the start-up dynamic simulation results of the SI process coupled to the IHX, which is one of components in the VHTR system, it is expected that the integrated secondary helium loop of the SI process can be successfully and safely approach the steady state condition.

  19. Iodine Adsorption by Ag-Aerogel under Prototypical Vessel Off-Gas Conditions

    Energy Technology Data Exchange (ETDEWEB)

    Bruffey, Stephanie H. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Jubin, Robert Thomas [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2016-08-01

    possible, as no iodine was observed to break through the sorbent beds. Continued studies on the adsorption of iodine from prototypical vessel off-gas streams by silver-based sorbents will attempt to resolve some of the questions raised here, both regarding mass balance and the effect of aging on iodine adsorption by AgAerogel from a dilute gas stream. Additionally, the adsorption of different iodine species, such as I2 and C12H25I will be studied. Other variables that merit examination are the gas velocity of the test and the dependence of the observed results on the inlet iodine concentration. Finally, longer duration testing should be considered in an effort to determine the mass transfer zone associated with iodine adsorption by AgAerogel under prototypical vessel off-gas conditions. The estimation of mass transfer zone is required for any future industrial implementation.

  20. Iodine Adsorption by Ag-Aerogel under Prototypical Vessel Off-Gas Conditions

    Energy Technology Data Exchange (ETDEWEB)

    Bruffey, Stephanie H. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Jubin, Robert Thomas [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2016-08-01

    possible, as no iodine was observed to break through the sorbent beds. Continued studies on the adsorption of iodine from prototypical vessel off-gas streams by silver-based sorbents will attempt to resolve some of the questions raised here, both regarding mass balance and the effect of aging on iodine adsorption by AgAerogel from a dilute gas stream. Additionally, the adsorption of different iodine species, such as I2 and C12H25I will be studied. Other variables that merit examination are the gas velocity of the test and the dependence of the observed results on the inlet iodine concentration. Finally, longer duration testing should be considered in an effort to determine the mass transfer zone associated with iodine adsorption by AgAerogel under prototypical vessel off-gas conditions. The estimation of mass transfer zone is required for any future industrial implementation.

  1. Modeling Longitudinal Data with Generalized Additive Models: Applications to Single-Case Designs

    Science.gov (United States)

    Sullivan, Kristynn J.; Shadish, William R.

    2013-01-01

    Single case designs (SCDs) are short time series that assess intervention effects by measuring units repeatedly over time both in the presence and absence of treatment. For a variety of reasons, interest in the statistical analysis and meta-analysis of these designs has been growing in recent years. This paper proposes modeling SCD data with…

  2. Formation and reduction of carcinogenic furan in various model systems containing food additives.

    Science.gov (United States)

    Kim, Jin-Sil; Her, Jae-Young; Lee, Kwang-Geun

    2015-12-15

    The aim of this study was to analyse and reduce furan in various model systems. Furan model systems consisting of monosaccharides (0.5M glucose and ribose), amino acids (0.5M alanine and serine) and/or 1.0M ascorbic acid were heated at 121°C for 25 min. The effects of food additives (each 0.1M) such as metal ions (iron sulphate, magnesium sulphate, zinc sulphate and calcium sulphate), antioxidants (BHT and BHA), and sodium sulphite on the formation of furan were measured. The level of furan formed in the model systems was 6.8-527.3 ng/ml. The level of furan in the model systems of glucose/serine and glucose/alanine increased 7-674% when food additives were added. In contrast, the level of furan decreased by 18-51% in the Maillard reaction model systems that included ribose and alanine/serine with food additives except zinc sulphate.

  3. NB-PLC channel modelling with cyclostationary noise addition & OFDM implementation for smart grid

    Science.gov (United States)

    Thomas, Togis; Gupta, K. K.

    2016-03-01

    Power line communication (PLC) technology can be a viable solution for the future ubiquitous networks because it provides a cheaper alternative to other wired technology currently being used for communication. In smart grid Power Line Communication (PLC) is used to support communication with low rate on low voltage (LV) distribution network. In this paper, we propose the channel modelling of narrowband (NB) PLC in the frequency range 5 KHz to 500 KHz by using ABCD parameter with cyclostationary noise addition. Behaviour of the channel was studied by the addition of 11KV/230V transformer, by varying load location and load. Bit error rate (BER) Vs signal to noise ratio SNR) was plotted for the proposed model by employing OFDM. Our simulation results based on the proposed channel model show an acceptable performance in terms of bit error rate versus signal to noise ratio, which enables communication required for smart grid applications.

  4. Iodine-129: a review of its potential impact on the environment

    Energy Technology Data Exchange (ETDEWEB)

    Poston, J.W.

    1978-05-01

    Attention has been drawn to /sup 129/I, a radionuclide with a long half-life and the potential for long-term accumulation in the environment as a result of low-level, chronic releases from nuclear facilities such as nuclear fuel reprocessing plants. The metabolic and physiologic data on iodine, as well as the currently accepted metabolic models, are summarized. In addition, projections of iodine-129 production and release, as well as estimates of the potential hazards derived by various authors, are presented and discussed. The implications of these considerations on the deep geologic disposal of /sup 129/I are reviewed and summarized. At this time there are limited data available to assess in detail the impact of releases of /sup 129/I to the environment from a geologic waste repository. Since this isotope is essentially stable (has a low specific activity because of its long radioactive half-life) it has been generally regarded as not contributing significantly to the total population dose commitment. Therefore, the presence of this isotope in a waste repository should not significantly affect repository design and operation. However, additional research in several areas such as the movement of /sup 129/I from a repository to the surface by ground water and the influence on uptake fraction of the incorporation of /sup 129/I in foodstuffs would be useful to more accurately quantify environmental effects.

  5. Estimation of iodine intake from various urinary iodine measurements in population studies

    DEFF Research Database (Denmark)

    Vejbjerg, P.; Knudsen, N.; Perrild, H.

    2009-01-01

    Background: Iodine intake is often measured by a surrogate measure, namely urine iodine excretion as almost all ingested iodine is excreted in the urine. However, the methods for urine collection and the reporting of the results vary. These methods, and their advantages and disadvantages, are con......Background: Iodine intake is often measured by a surrogate measure, namely urine iodine excretion as almost all ingested iodine is excreted in the urine. However, the methods for urine collection and the reporting of the results vary. These methods, and their advantages and disadvantages......, are considered in this article. Summary: There are two main ways in which urine can be collected for iodine measurement. The first is the collection of urine over a period, usually 24 hours. The second is the collection of a spot urinary sample. Urinary iodine values can be expressed as the content...... or concentration and reported without modification or as a function of creatinine in the same sample. The 24-hour urine for iodine measurement is often considered as the “reference standard” for giving a precise estimate of the individual iodine excretion and thereby iodine intake. As 24-hour collections...

  6. Experimental study on iodine chemistry (EXSI) - Containment experiments with elemental iodine

    Energy Technology Data Exchange (ETDEWEB)

    Kaerkelae, T.; Auvinen, A. (VTT Technical Research Centre of Finland (Finland)); Holm, J.; Ekberg, C. (Chalmers Univ. of Technology (Sweden)); Glaenneskog, H. (Vattenfall Power Consultant (Sweden))

    2009-10-15

    The behaviour of iodine during a severe accident has been studied in several experimental programs, ranging from the large-scale PHEBUS FP tests and intermediate-scale ThAI tests to numerous separate effect studies. Oxidation of iodine in gas phase has been one of the greatest remaining uncertainties in iodine behaviour during a severe accident. In this study the possible formation of iodine oxide aerosol due to radiolytic oxidation of gaseous iodine is experimentally tested and the reaction products are analysed. The experimental facility applied in this study is based on the sampling system built at VTT for ISTP program project CHIP conducted IRSN. The experimental facility and the measuring technology are sophisticated and unique in the area of nuclear research as well as in the field of aerosol science. The results from the experiments show an extensive particle formation when ozone and gaseous iodine react with each other. The formed particles were collected on filters, while gaseous iodine was trapped into bubbles. The particles were iodine oxides and the size of particles was approximately 100 nm. The transport of gaseous iodine through the facility decreased when both gaseous iodine and ozone were fed together into facility. Experimental study on radiolytic oxidation of iodine was conducted in co-operation between VTT and Chalmers University of Technology as a part of the NKS-R programs. (author)

  7. Open Source Software for Mapping Human Impacts on Marine Ecosystems with an Additive Model

    Directory of Open Access Journals (Sweden)

    Andy Stock

    2016-06-01

    Full Text Available This paper describes an easy-to-use open source software tool implementing a commonly used additive model (Halpern et al., 'Science', 2008 for mapping human impacts on marine ecosystems. The tool has been used to map the potential for cumulative human impacts in Arctic marine waters and can support future human impact mapping projects by 1 making the model easier to use; 2 making updates of model results straightforward when better input data become available; 3 storing input data and information about processing steps in a defined format and thus facilitating data sharing and reproduction of modeling results; 4 supporting basic visualization of model inputs and outputs without the need for advanced technical skills. The tool, called EcoImpactMapper, was implemented in Java and is thus platform-independent. A tutorial, example data, the tool and the source code are available online.

  8. Estimation for an additive growth curve model with orthogonal design matrices

    CERN Document Server

    Hu, Jianhua; You, Jinhong; 10.3150/10-BEJ315

    2012-01-01

    An additive growth curve model with orthogonal design matrices is proposed in which observations may have different profile forms. The proposed model allows us to fit data and then estimate parameters in a more parsimonious way than the traditional growth curve model. Two-stage generalized least-squares estimators for the regression coefficients are derived where a quadratic estimator for the covariance of observations is taken as the first-stage estimator. Consistency, asymptotic normality and asymptotic independence of these estimators are investigated. Simulation studies and a numerical example are given to illustrate the efficiency and parsimony of the proposed model for model specifications in the sense of minimizing Akaike's information criterion (AIC).

  9. The additive nonparametric and semiparametric Aalen model as the rate function for a counting process

    DEFF Research Database (Denmark)

    Scheike, Thomas Harder

    2002-01-01

    We use the additive risk model of Aalen (Aalen, 1980) as a model for the rate of a counting process. Rather than specifying the intensity, that is the instantaneous probability of an event conditional on the entire history of the relevant covariates and counting processes, we present a model...... for the rate function, i.e., the instantaneous probability of an event conditional on only a selected set of covariates. When the rate function for the counting process is of Aalen form we show that the usual Aalen estimator can be used and gives almost unbiased estimates. The usual martingale based variance...... estimator is incorrect and an alternative estimator should be used. We also consider the semi-parametric version of the Aalen model as a rate model (McKeague and Sasieni, 1994) and show that the standard errors that are computed based on an assumption of intensities are incorrect and give a different...

  10. Iodine deficiency in Australia: is iodine supplementation for pregnant and lactating women warranted?

    Science.gov (United States)

    Gallego, Gisselle; Goodall, Stephen; Eastman, Creswell J

    2010-04-19

    Recent research has confirmed that Australian children and pregnant women are mildly iodine deficient. A considerable proportion of the pregnant population is moderately to severely iodine deficient. Even subclinical hypothyroidism in the mother, occurring as a consequence of iodine deficiency, can cause irreversible brain damage in the fetus, making it essential to avoid iodine deficiency in pregnancy. The proposal of Food Standards Australia and New Zealand (FSANZ) - Mandatory Iodine Fortification for Australia (P1003) - has been implemented. FSANZ openly admits P1003 is inadequate for covering the needs of pregnant women. Therefore, health professionals and the public must be properly informed about the limitations of this proposal. Views differ about the most effective measures to prevent iodine deficiency in Australia. We propose that women planning a pregnancy, and pregnant and lactating women should be advised to take an iodine supplement. Women with pre-existing thyroid disease should exercise caution and seek medical advice before taking a supplement.

  11. Iodine deficiency in pregnancy in Denmark. Regional variations and frequency of individual iodine supplementation

    DEFF Research Database (Denmark)

    Nøhr, S B; Laurberg, Peter; Børlum, K G

    1993-01-01

    Iodine requirements are increased during pregnancy and lactation and adequate iodine intake is important for normal brain development of the fetus/newborn child. The aim of the present study was to evaluate the extent to which this increase in iodine requirement is met in pregnant women living...... containing vitamin/mineral tablets. Approximately one third of the women had received tablets containing iodine. In women who had not received iodine supplementation urinary iodine was low with a median value of 39.7 micrograms/g creatinine (Aalborg 28, Randers 33, Ringkøbing 34, Arhus 43 and Copenhagen 62...... micrograms/g creatinine). These values are far below internationally recommended levels. The consequences remain to be evaluated and no firm recommendations can be given. It seems reasonable, however, to recommend a high intake of food containing iodine (e.g. milk products) during pregnancy and lactation...

  12. The interaction of iodine with organic material in containment

    Energy Technology Data Exchange (ETDEWEB)

    Wren, J.C.; Ball, J.M.; Glown, G.A.; Portmann, R.; Sanipelli, G.G. [Atomic Energy of Canada Ltd., Pinawa, MB (Canada). Whiteshell Labs.

    1996-12-01

    Organic impurities in containment water, originating from various painted structural surfaces and organic containment materials, could have a significant impact on iodine volatility following an accident. A research program has been designed to determine the impact of organic impurities on iodine volatility under accident conditions. The program consists of experimental, literature and modelling studies on the radiolysis or organic compounds in the aqueous phase, thermal and radiolytic formation and decomposition of organic iodides, dissolution of organic solvents from various painted surfaces into the aqueous phase, and iodine deposition on painted surfaces. The experimental studies consist of bench-scale `separate effects` tests as well as intermediate-scale `integrated effects` in the Radioiodine Test facility. The studies have shown that organic impurities will be found in containment water, arising from the dissolution of organic compounds from various surface paints and that these compounds can potentially have a significant impact on iodine volatility following an accident. The main impact of surface paints will occur through aqueous-phase reactions of the organic compounds that they release to the aqueous phase. Under the radiation conditions expected during an accident, these compounds will react to reduce the pH and dissolved oxygen concentration, consequently increasing the formation of I{sub 2} from I{sup -} that is present in the sump. It appears that the rates of these processes may be controlled by the dissolution kinetics of the organic compounds from the surface coatings. Moreover, the organic compounds may also react thermally and radiolytically with I{sub 2} to form organic iodides in the aqueous phase. Our studies have shown that the formation of organic iodides from soluble organics such as ketones, alcohols and phenols may have more impact on the total iodine volatility than the formation of CH{sub 3}I. (author) 13 figs., 2 tabs., 19 refs.

  13. EFFECT OF NANOPOWDER ADDITION ON THE FLEXURAL STRENGTH OF ALUMINA CERAMIC - A WEIBULL MODEL ANALYSIS

    Directory of Open Access Journals (Sweden)

    Daidong Guo

    2016-05-01

    Full Text Available Alumina ceramics were prepared either with micrometer-sized alumina powder (MAP or with the addition of nanometer-sized alumina powder (NAP. The density, crystalline phase, flexural strength and the fracture surface of the two ceramics were measured and compared. Emphasis has been put on the influence of nanopowder addition on the flexural strength of Al₂O₃ ceramic. The analysis based on the Weibull distribution model suggests the distribution of the flexural strength of the NAP ceramic is more concentrated than that of the MAP ceramic. Therefore, the NAP ceramics will be more stable and reliable in real applications.

  14. [Adaptation of thyroid function to excess iodine].

    Science.gov (United States)

    Aurengo, Andre; Leenhardt, Laurence; Aurengo, Helyett

    2002-10-26

    NORMALLY: The production of thyroid hormones is normally stable, despite iodine supplies that may vary widely and even on sudden excess iodine. The metabolism of iodine is characterised by adapted thyroid uptake, the requirements varying on the age and physiological status of the individual (pregnancy, breastfeeding) and by insufficient supplies in several areas in France. IN THE CASE OF EXCESS: The mechanisms that permit the thyroid to adapt to a sudden or chronic excess of iodine are immature in the newborn and sometimes deficient in adults, and may lead to iodine-induced dysthyroidism. Thanks to the recent progress made in thyroid physiology, these mechanisms are now better known. PATHOLOGICAL IMPACT: Iodine-induced hyperthyroidisms in a healthy or pathological thyroid are frequent. They are predominantly related to amiodarone. Iodine-related hypothyroidism frequently appears in cases of pre-existing thyroid diseases (asymptomatic autoimmune thyroiditis, for example). They are frequent in the newborn, notably in the premature. The iodine prophylaxis organised in Poland following the Tchernobyl accident led to very few pathological consequences in adults or children.

  15. Sorption of iodine onto Japanese soils

    Energy Technology Data Exchange (ETDEWEB)

    Yoshida, Satoshi [National Inst. of Radiological Sciences, Hitachinaka, Ibaraki (Japan). Nakaminato Lab. Branch

    1996-04-01

    Soils were collected from various regions of Japan. Iodine concentrations in the soils were quantitatively determined. The adsorption ratio and the distribution coefficients of iodine onto the soils were derived and effects of co-existing ions were studied. (J.P.N.)

  16. Efficient semiparametric estimation in generalized partially linear additive models for longitudinal/clustered data

    KAUST Repository

    Cheng, Guang

    2014-02-01

    We consider efficient estimation of the Euclidean parameters in a generalized partially linear additive models for longitudinal/clustered data when multiple covariates need to be modeled nonparametrically, and propose an estimation procedure based on a spline approximation of the nonparametric part of the model and the generalized estimating equations (GEE). Although the model in consideration is natural and useful in many practical applications, the literature on this model is very limited because of challenges in dealing with dependent data for nonparametric additive models. We show that the proposed estimators are consistent and asymptotically normal even if the covariance structure is misspecified. An explicit consistent estimate of the asymptotic variance is also provided. Moreover, we derive the semiparametric efficiency score and information bound under general moment conditions. By showing that our estimators achieve the semiparametric information bound, we effectively establish their efficiency in a stronger sense than what is typically considered for GEE. The derivation of our asymptotic results relies heavily on the empirical processes tools that we develop for the longitudinal/clustered data. Numerical results are used to illustrate the finite sample performance of the proposed estimators. © 2014 ISI/BS.

  17. A negative feedback between anthropogenic ozone pollution and enhanced ocean emissions of iodine

    OpenAIRE

    Prados-Roman, C; Cuevas, C.A.; R. P. Fernandez; Kinnison, D. E.; Lamarque, J-F.; A. Saiz-Lopez

    2015-01-01

    © 2015 Author(s). CC Attribution 3.0 License. Naturally emitted from the oceans, iodine compounds efficiently destroy atmospheric ozone and reduce its positive radiative forcing effects in the troposphere. Emissions of inorganic iodine have been experimentally shown to depend on the deposition to the oceans of tropospheric ozone, whose concentrations have significantly increased since 1850 as a result of human activities. A chemistry-climate model is used herein to quantify the current ocean ...

  18. Generalized neurofuzzy network modeling algorithms using Bézier-Bernstein polynomial functions and additive decomposition.

    Science.gov (United States)

    Hong, X; Harris, C J

    2000-01-01

    This paper introduces a new neurofuzzy model construction algorithm for nonlinear dynamic systems based upon basis functions that are Bézier-Bernstein polynomial functions. This paper is generalized in that it copes with n-dimensional inputs by utilising an additive decomposition construction to overcome the curse of dimensionality associated with high n. This new construction algorithm also introduces univariate Bézier-Bernstein polynomial functions for the completeness of the generalized procedure. Like the B-spline expansion based neurofuzzy systems, Bézier-Bernstein polynomial function based neurofuzzy networks hold desirable properties such as nonnegativity of the basis functions, unity of support, and interpretability of basis function as fuzzy membership functions, moreover with the additional advantages of structural parsimony and Delaunay input space partition, essentially overcoming the curse of dimensionality associated with conventional fuzzy and RBF networks. This new modeling network is based on additive decomposition approach together with two separate basis function formation approaches for both univariate and bivariate Bézier-Bernstein polynomial functions used in model construction. The overall network weights are then learnt using conventional least squares methods. Numerical examples are included to demonstrate the effectiveness of this new data based modeling approach.

  19. The effect of tailor-made additives on crystal growth of methyl paraben: Experiments and modelling

    Science.gov (United States)

    Cai, Zhihui; Liu, Yong; Song, Yang; Guan, Guoqiang; Jiang, Yanbin

    2017-03-01

    In this study, methyl paraben (MP) was selected as the model component, and acetaminophen (APAP), p-methyl acetanilide (PMAA) and acetanilide (ACET), which share the similar molecular structure as MP, were selected as the three tailor-made additives to study the effect of tailor-made additives on the crystal growth of MP. HPLC results indicated that the MP crystals induced by the three additives contained MP only. Photographs of the single crystals prepared indicated that the morphology of the MP crystals was greatly changed by the additives, but PXRD and single crystal diffraction results illustrated that the MP crystals were the same polymorph only with different crystal habits, and no new crystal form was found compared with other references. To investigate the effect of the additives on the crystal growth, the interaction between additives and facets was discussed in detail using the DFT methods and MD simulations. The results showed that APAP, PMAA and ACET would be selectively adsorbed on the growth surfaces of the crystal facets, which induced the change in MP crystal habits.

  20. A flexible additive inflation scheme for treating model error in ensemble Kalman Filters

    Science.gov (United States)

    Sommer, Matthias; Janjic, Tijana

    2017-04-01

    Data assimilation algorithms require an accurate estimate of the uncertainty of the prior, background, field. However, the background error covariance derived from the ensemble of numerical model simulations does not adequately represent the uncertainty of it. This is partially due to the sampling error that arises from the use of a small number of ensemble members to represent the background error covariance. It is also partially a consequence of the fact that the model does not represent its own error. Several mechanisms have been introduced so far aiming at alleviating the detrimental e ffects of misrepresented ensemble covariances, allowing for the successful implementation of ensemble data assimilation techniques for atmospheric dynamics. One of the established approaches in ensemble data assimilation is additive inflation which perturbs each ensemble member with a sample from a given distribution. This results in a fixed rank of the model error covariance matrix. Here, a more flexible approach is suggested where the model error samples are treated as additional synthetic ensemble members which are used in the update step of data assimilation but are not forecast. In this way, the rank of the model error covariance matrix can be chosen independently of the ensemble. The eff ect of this altered additive inflation method on the performance of the filter is analyzed here in an idealised experiment. It is shown that the additional synthetic ensemble members can make it feasible to achieve convergence in an otherwise divergent setting of data assimilation. The use of this method also allows for a less stringent localization radius.

  1. Fluorescence analysis of iodinated acetophenone derivatives.

    Science.gov (United States)

    Crivelaro, F; Oliveira, M R S; Lima, S M; Andrade, L H C; Casagrande, G A; Raminelli, C; Caires, A R L

    2015-03-15

    In the present paper the synthesis and optical characterization of iodinated acetophenone, 4-hydroxy-3-iodoacetophenone and 4-hydroxy-3,5-diiodoacetophenone obtained from 4-hydroxyacetophenone, were carried out. The optical features of iodinated molecules were determined by performing the UV-Vis absorption, fluorescence and thermal lens spectroscopies. The results showed that the optical properties of the 4-hydroxyacetophenone is altered when the iodine atom is inserted, as substituent, in the aromatic ring. Although it was determined that the optical feature was changed when one iodine atom was inserted in the aromatic ring (4-hydroxy-3-iodoacetophenone), the results revealed that emission behavior was strongly altered when two iodine atoms (4-hydroxy-3,5-diiodoacetophenone) were acting as substituents: the fluorescence quantum efficiency increases approximately 60%.

  2. Test of the Additivity Principle for Current Fluctuations in a Model of Heat Conduction

    Science.gov (United States)

    Hurtado, Pablo I.; Garrido, Pedro L.

    2009-06-01

    The additivity principle allows to compute the current distribution in many one-dimensional (1D) nonequilibrium systems. Using simulations, we confirm this conjecture in the 1D Kipnis-Marchioro-Presutti model of heat conduction for a wide current interval. The current distribution shows both Gaussian and non-Gaussian regimes, and obeys the Gallavotti-Cohen fluctuation theorem. We verify the existence of a well-defined temperature profile associated to a given current fluctuation. This profile is independent of the sign of the current, and this symmetry extends to higher-order profiles and spatial correlations. We also show that finite-time joint fluctuations of the current and the profile are described by the additivity functional. These results suggest the additivity hypothesis as a general and powerful tool to compute current distributions in many nonequilibrium systems.

  3. Generalized Additive Mixed-Models for Pharmacology Using Integrated Discrete Multiple Organ Co-Culture

    Science.gov (United States)

    Ingersoll, Thomas; Cole, Stephanie; Madren-Whalley, Janna; Booker, Lamont; Dorsey, Russell; Li, Albert; Salem, Harry

    2016-01-01

    Integrated Discrete Multiple Organ Co-culture (IDMOC) is emerging as an in-vitro alternative to in-vivo animal models for pharmacology studies. IDMOC allows dose-response relationships to be investigated at the tissue and organoid levels, yet, these relationships often exhibit responses that are far more complex than the binary responses often measured in whole animals. To accommodate departure from binary endpoints, IDMOC requires an expansion of analytic techniques beyond simple linear probit and logistic models familiar in toxicology. IDMOC dose-responses may be measured at continuous scales, exhibit significant non-linearity such as local maxima or minima, and may include non-independent measures. Generalized additive mixed-modeling (GAMM) provides an alternative description of dose-response that relaxes assumptions of independence and linearity. We compared GAMMs to traditional linear models for describing dose-response in IDMOC pharmacology studies. PMID:27110941

  4. Use of additive technologies for practical working with complex models for foundry technologies

    Science.gov (United States)

    Olkhovik, E.; Butsanets, A. A.; Ageeva, A. A.

    2016-07-01

    The article presents the results of research of additive technology (3D printing) application for developing a geometrically complex model of castings parts. Investment casting is well known and widely used technology for the production of complex parts. The work proposes the use of a 3D printing technology for manufacturing models parts, which are removed by thermal destruction. Traditional methods of equipment production for investment casting involve the use of manual labor which has problems with dimensional accuracy, and CNC technology which is less used. Such scheme is low productive and demands considerable time. We have offered an alternative method which consists in printing the main knots using a 3D printer (PLA and ABS) with a subsequent production of castings models from them. In this article, the main technological methods are considered and their problems are discussed. The dimensional accuracy of models in comparison with investment casting technology is considered as the main aspect.

  5. Modeling of sulfation of potassium chloride by ferric sulfate addition during grate-firing of biomass

    DEFF Research Database (Denmark)

    Wu, Hao; Jespersen, Jacob Boll; Aho, Martti

    2013-01-01

    Potassium chloride, KCl, formed from critical ash-forming elements released during combustion may lead to severe ash deposition and corrosion problems in biomass-fired boilers. Ferric sulfate, Fe2(SO4)3 is an effective additive, which produces sulfur oxides (SO2 and SO3) to convert KCl to the less...... harmful K2SO4. In the present study the decomposition of ferric sulfate is studied in a fast-heating rate thermogravimetric analyzer (TGA), and a kinetic model is proposed to describe the decomposition process. The yields of SO2 and SO3 from ferric sulfate decomposition are investigated in a laboratory......-scale tube reactor. It is revealed that approximately 40% of the sulfur is released as SO3, the remaining fraction being released as SO2. The proposed decomposition model of ferric sulfate is combined with a detailed gas phase kinetic model of KCl sulfation, and a simplified model of K2SO4 condensation...

  6. Generalized Additive Mixed-Models for Pharmacology Using Integrated Discrete Multiple Organ Co-Culture.

    Directory of Open Access Journals (Sweden)

    Thomas Ingersoll

    Full Text Available Integrated Discrete Multiple Organ Co-culture (IDMOC is emerging as an in-vitro alternative to in-vivo animal models for pharmacology studies. IDMOC allows dose-response relationships to be investigated at the tissue and organoid levels, yet, these relationships often exhibit responses that are far more complex than the binary responses often measured in whole animals. To accommodate departure from binary endpoints, IDMOC requires an expansion of analytic techniques beyond simple linear probit and logistic models familiar in toxicology. IDMOC dose-responses may be measured at continuous scales, exhibit significant non-linearity such as local maxima or minima, and may include non-independent measures. Generalized additive mixed-modeling (GAMM provides an alternative description of dose-response that relaxes assumptions of independence and linearity. We compared GAMMs to traditional linear models for describing dose-response in IDMOC pharmacology studies.

  7. Modeling the Use of Sulfate Additives for Potassium Chloride Destruction in Biomass Combustion

    DEFF Research Database (Denmark)

    Wu, Hao; Pedersen, Morten Nedergaard; Jespersen, Jacob Boll;

    2014-01-01

    Potassium chloride, KCl, formed from biomass combustion may lead to ash deposition and corrosion problems in boilers. Sulfates are effective additives for converting KCl to the less harmful K2SO4 and HCl. In the present study, the rate constants for decomposition of ammonium sulfate and aluminum...... sulfate were obtained from experiments in a fast heating rate thermogravimetric analyzer. The yields of SO2 and SO3 from the decomposition were investigated in a tube reactor at 600–900 °C, revealing a constant distribution of about 15% SO2 and 85% SO3 from aluminum sulfate decomposition and a temperature......-dependent distribution of SO2 and SO3 from ammonium sulfate decomposition. On the basis of these data as well as earlier results, a detailed chemical kinetic model for sulfation of KCl by a range of sulfate additives was established. Modeling results were compared to biomass combustion experiments in a bubbling...

  8. The importance of iodine in public health.

    Science.gov (United States)

    Lazarus, John H

    2015-08-01

    Iodine (I) deficiency has been known for more than a century and is known to cause cretinism at the extreme end of the spectrum but also, importantly, impaired development and neurocognition in areas of mild deficiency. The WHO has indicated that median urinary iodine of 100-199 μg/l in a population is regarded as indicative of an adequate iodine intake. The understanding of the spectrum of iodine deficiency disorders led to the formation of The International Council for the Control of Iodine Deficiency Disorders which has promulgated the use of household iodized salt and the use of such salt in food processing and manufacture. Iodine deficiency is particularly important in pregnancy as the fetus relies on maternal thyroxine (T4) exclusively during the first 14 weeks and also throughout gestation. As this hormone is critical to brain and nervous system maturation, low maternal T4 results in low child intelligence quotient. The recommendation for I intake in pregnancy is 250 μg/day to prevent fetal and child brain function impairment. During the past 25 years, the number of countries with I deficiency has reduced to 32; these still include many European developed countries. Sustainability of adequate iodine status must be achieved by continuous monitoring and where this has not been performed I deficiency has often recurred. More randomized controlled trials of iodine supplementation in pregnancy are required in mild iodine-deficient areas to inform public health strategy and subsequent government action on suitable provision of iodine to the population at risk.

  9. Choosing components in the additive main effect and multiplicative interaction (AMMI models

    Directory of Open Access Journals (Sweden)

    Dias Carlos Tadeu dos Santos

    2006-01-01

    Full Text Available The additive main effect and multiplicative interaction (AMMI models allows analysts to detect interactions between rows and columns in a two-way table. However, there are many methods proposed in the literature to determine the number of multiplicative components to include in the AMMI model. These methods typically give different results for any particular data set, so the user needs some guidance as to which methods to use. In this paper we compare four commonly used methods using simulated data based on real experiments, and provide some general recommendations.

  10. Modeling of Ti-W Solidification Microstructures Under Additive Manufacturing Conditions

    Science.gov (United States)

    Rolchigo, Matthew R.; Mendoza, Michael Y.; Samimi, Peyman; Brice, David A.; Martin, Brian; Collins, Peter C.; LeSar, Richard

    2017-07-01

    Additive manufacturing (AM) processes have many benefits for the fabrication of alloy parts, including the potential for greater microstructural control and targeted properties than traditional metallurgy processes. To accelerate utilization of this process to produce such parts, an effective computational modeling approach to identify the relationships between material and process parameters, microstructure, and part properties is essential. Development of such a model requires accounting for the many factors in play during this process, including laser absorption, material addition and melting, fluid flow, various modes of heat transport, and solidification. In this paper, we start with a more modest goal, to create a multiscale model for a specific AM process, Laser Engineered Net Shaping (LENS™), which couples a continuum-level description of a simplified beam melting problem (coupling heat absorption, heat transport, and fluid flow) with a Lattice Boltzmann-cellular automata (LB-CA) microscale model of combined fluid flow, solute transport, and solidification. We apply this model to a binary Ti-5.5 wt pct W alloy and compare calculated quantities, such as dendrite arm spacing, with experimental results reported in a companion paper.

  11. Model for Assembly Line Re-Balancing Considering Additional Capacity and Outsourcing to Face Demand Fluctuations

    Science.gov (United States)

    Samadhi, TMAA; Sumihartati, Atin

    2016-02-01

    The most critical stage in a garment industry is sewing process, because generally, it consists of a number of operations and a large number of sewing machines for each operation. Therefore, it requires a balancing method that can assign task to work station with balance workloads. Many studies on assembly line balancing assume a new assembly line, but in reality, due to demand fluctuation and demand increased a re-balancing is needed. To cope with those fluctuating demand changes, additional capacity can be carried out by investing in spare sewing machine and paying for sewing service through outsourcing. This study develops an assembly line balancing (ALB) model on existing line to cope with fluctuating demand change. Capacity redesign is decided if the fluctuation demand exceeds the available capacity through a combination of making investment on new machines and outsourcing while considering for minimizing the cost of idle capacity in the future. The objective of the model is to minimize the total cost of the line assembly that consists of operating costs, machine cost, adding capacity cost, losses cost due to idle capacity and outsourcing costs. The model develop is based on an integer programming model. The model is tested for a set of data of one year demand with the existing number of sewing machines of 41 units. The result shows that additional maximum capacity up to 76 units of machine required when there is an increase of 60% of the average demand, at the equal cost parameters..

  12. Introducing COZIGAM: An R Package for Unconstrained and Constrained Zero-Inflated Generalized Additive Model Analysis

    Directory of Open Access Journals (Sweden)

    Hai Liu

    2010-10-01

    Full Text Available Zero-inflation problem is very common in ecological studies as well as other areas. Nonparametric regression with zero-inflated data may be studied via the zero-inflated generalized additive model (ZIGAM, which assumes that the zero-inflated responses come from a probabilistic mixture of zero and a regular component whose distribution belongs to the 1-parameter exponential family. With the further assumption that the probability of non-zero-inflation is some monotonic function of the mean of the regular component, we propose the constrained zero-inflated generalized additive model (COZIGAM for analyzingzero-inflated data. When the hypothesized constraint obtains, the new approach provides a unified framework for modeling zero-inflated data, which is more parsimonious and efficient than the unconstrained ZIGAM. We have developed an R package COZIGAM which contains functions that implement an iterative algorithm for fitting ZIGAMs and COZIGAMs to zero-inflated data basedon the penalized likelihood approach. Other functions included in the package are useful for model prediction and model selection. We demonstrate the use of the COZIGAM package via some simulation studies and a real application.

  13. Patient-specific in vitro models for hemodynamic analysis of congenital heart disease - Additive manufacturing approach.

    Science.gov (United States)

    Medero, Rafael; García-Rodríguez, Sylvana; François, Christopher J; Roldán-Alzate, Alejandro

    2017-03-21

    Non-invasive hemodynamic assessment of total cavopulmonary connection (TCPC) is challenging due to the complex anatomy. Additive manufacturing (AM) is a suitable alternative for creating patient-specific in vitro models for flow measurements using four-dimensional (4D) Flow MRI. These in vitro systems have the potential to serve as validation for computational fluid dynamics (CFD), simulating different physiological conditions. This study investigated three different AM technologies, stereolithography (SLA), selective laser sintering (SLS) and fused deposition modeling (FDM), to determine differences in hemodynamics when measuring flow using 4D Flow MRI. The models were created using patient-specific MRI data from an extracardiac TCPC. These models were connected to a perfusion pump circulating water at three different flow rates. Data was processed for visualization and quantification of velocity, flow distribution, vorticity and kinetic energy. These results were compared between each model. In addition, the flow distribution obtained in vitro was compared to in vivo. The results showed significant difference in velocities measured at the outlets of the models that required internal support material when printing. Furthermore, an ultrasound flow sensor was used to validate flow measurements at the inlets and outlets of the in vitro models. These results were highly correlated to those measured with 4D Flow MRI. This study showed that commercially available AM technologies can be used to create patient-specific vascular models for in vitro hemodynamic studies at reasonable costs. However, technologies that do not require internal supports during manufacturing allow smoother internal surfaces, which makes them better suited for flow analyses. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. The Additive Risk Model for Estimation of Effect of Haplotype Match in BMT Studies

    DEFF Research Database (Denmark)

    Scheike, Thomas; Martinussen, T; Zhang, MJ

    2011-01-01

    leads to a missing data problem. We show how Aalen's additive risk model can be applied in this setting with the benefit that the time-varying haplomatch effect can be easily studied. This problem has not been considered before, and the standard approach where one would use the expected-maximization (EM...... be developed using product-integration theory. Small sample properties are investigated using simulations in a setting that mimics the motivating haplomatch problem....

  15. Application of power addition as modelling technique for flow processes: Two case studies

    CSIR Research Space (South Africa)

    de Wet, P

    2010-05-01

    Full Text Available addition as modelling technique for flow processes: Two case studies Pierre de Wet a,�, J. Prieur du Plessis b, Sonia Woudberg b a Council for Scientific & Industrial Research (CSIR), PO Box 320, Stellenbosch 7599, South Africa b Applied Mathematics... research on precise, credible experimental practices is undeniable. The empirical equations derived from these investigations impart understanding of the underlying physics are crucial for the development of computational routines and form an integral...

  16. Development of a QTL-environment-based predictive model for node addition rate in common bean.

    Science.gov (United States)

    Zhang, Li; Gezan, Salvador A; Eduardo Vallejos, C; Jones, James W; Boote, Kenneth J; Clavijo-Michelangeli, Jose A; Bhakta, Mehul; Osorno, Juan M; Rao, Idupulapati; Beebe, Stephen; Roman-Paoli, Elvin; Gonzalez, Abiezer; Beaver, James; Ricaurte, Jaumer; Colbert, Raphael; Correll, Melanie J

    2017-05-01

    This work reports the effects of the genetic makeup, the environment and the genotype by environment interactions for node addition rate in an RIL population of common bean. This information was used to build a predictive model for node addition rate. To select a plant genotype that will thrive in targeted environments it is critical to understand the genotype by environment interaction (GEI). In this study, multi-environment QTL analysis was used to characterize node addition rate (NAR, node day(- 1)) on the main stem of the common bean (Phaseolus vulgaris L). This analysis was carried out with field data of 171 recombinant inbred lines that were grown at five sites (Florida, Puerto Rico, 2 sites in Colombia, and North Dakota). Four QTLs (Nar1, Nar2, Nar3 and Nar4) were identified, one of which had significant QTL by environment interactions (QEI), that is, Nar2 with temperature. Temperature was identified as the main environmental factor affecting NAR while day length and solar radiation played a minor role. Integration of sites as covariates into a QTL mixed site-effect model, and further replacing the site component with explanatory environmental covariates (i.e., temperature, day length and solar radiation) yielded a model that explained 73% of the phenotypic variation for NAR with root mean square error of 16.25% of the mean. The QTL consistency and stability was examined through a tenfold cross validation with different sets of genotypes and these four QTLs were always detected with 50-90% probability. The final model was evaluated using leave-one-site-out method to assess the influence of site on node addition rate. These analyses provided a quantitative measure of the effects on NAR of common beans exerted by the genetic makeup, the environment and their interactions.

  17. Mathematical modeling of polyphenolic additive made from grape stone with for meet products

    Directory of Open Access Journals (Sweden)

    Інна Олександрівна Літвінова

    2015-07-01

    Full Text Available In the article the optimal parameters are defined to obtain polyphenol additive made from grape stone of antioxidant purpose – "Maltovyn" by the method of mathematical planning of multifactor experiments. Research is conducted under the matrix of D-quadratic optimal plan of experiments. The results of microwave extraction process of phenolic compounds with maximum antioxidant activity are obtained. It was established that the selected model provides a set of detection values that minimize divergence of calculated and experimental data

  18. Rain water transport and storage in a model sandy soil with hydrogel particle additives.

    Science.gov (United States)

    Wei, Y; Durian, D J

    2014-10-01

    We study rain water infiltration and drainage in a dry model sandy soil with superabsorbent hydrogel particle additives by measuring the mass of retained water for non-ponding rainfall using a self-built 3D laboratory set-up. In the pure model sandy soil, the retained water curve measurements indicate that instead of a stable horizontal wetting front that grows downward uniformly, a narrow fingered flow forms under the top layer of water-saturated soil. This rain water channelization phenomenon not only further reduces the available rain water in the plant root zone, but also affects the efficiency of soil additives, such as superabsorbent hydrogel particles. Our studies show that the shape of the retained water curve for a soil packing with hydrogel particle additives strongly depends on the location and the concentration of the hydrogel particles in the model sandy soil. By carefully choosing the particle size and distribution methods, we may use the swollen hydrogel particles to modify the soil pore structure, to clog or extend the water channels in sandy soils, or to build water reservoirs in the plant root zone.

  19. Dietary sodium and iodine in remote Indigenous Australian communities: will salt-reduction strategies increase risk of iodine deficiency? A cross-sectional analysis and simulation study.

    Science.gov (United States)

    McMahon, Emma; Webster, Jacqui; O'Dea, Kerin; Brimblecombe, Julie

    2015-12-30

    Excess salt intake is a global issue. Effective salt-reduction strategies are needed, however, as salt is a vehicle for iodine fortification, these strategies may also reduce iodine intake. This study examines the case of the remote Indigenous Australian population; we employed an innovative, objective method to assess sodium and iodine intakes against requirements and modelled the potential effects of salt-reduction strategies on estimated sodium and iodine intakes. Store-sales data were collected from 20 remote Indigenous community stores in 2012-14 representing the main source of food for 2 years for ~8300 individuals. Estimated average sodium and iodine intakes were compared against recommendations (nutrient reference values weighted to age and gender distribution). Linear programming was employed to simulate potential effects of salt-reduction strategies on estimated sodium and iodine intakes. Estimated average sodium intake was 2770 (range within communities 2410-3450) mg/day, far exceeding the population-weighted upper limit (2060 mg/day). Discretionary (added) salt, bread and processed meat were the biggest contributors providing 46% of all sodium. Estimated average iodine intake was within recommendations at 206 (186-246) μg/day. The following scenarios enabled modelling of estimated average salt intake to within recommendations: 1) 67% reduction in sodium content of bread and discretionary salt intake, 2) 38% reduction in sodium content of all processed foods, 3) 30% reduction in sodium content of all processed foods and discretionary salt intake. In all scenarios, simulated average iodine intakes remained within recommendations. Salt intakes of the remote Indigenous Australian population are far above recommendations, likely contributing to the high prevalence of hypertension and cardiovascular mortality experienced by this population. Salt-reduction strategies could considerably reduce salt intake in this population without increasing risk of iodine

  20. Selenium status, thyroid volume, and multiple nodule formation in an area with mild iodine deficiency

    DEFF Research Database (Denmark)

    Rasmussen, Lone Banke; Schomburg, Lutz; Kohrle, Josef;

    2011-01-01

    Objective: The objective was to study the associations between serum selenium concentration and thyroid volume, as well as the association between serum selenium concentration and risk for an enlarged thyroid gland in an area with mild iodine deficiency before and after iodine fortification......) introduction of iodine fortification. Serum selenium concentration and urinary iodine were measured, and the thyroid gland was examined by ultrasonography in the same subjects. Associations between serum selenium concentration and thyroid parameters were examined in multiple linear regression models...... was introduced. Another objective was to examine the association between serum selenium concentration and prevalence of thyroid nodules.Design: Cross-sectional study.Methods: We studied participants of two similar cross-sectional studies carried out before (1997-1998, n=405) and after (2004-2005, n=400...

  1. Ensuring effective prevention of iodine-deficiency disorders

    DEFF Research Database (Denmark)

    Völzke, Henry; Caron, Philippe Jean; Dahl, Lisbeth;

    2016-01-01

    BACKGROUND: Programs initiated to prevent iodine deficiency disorders (IDD) may not remain effective due to changes in government policies, commercial factors, and human behavior that may affect the efficacy of IDD prevention programs in unpredictable directions. Monitoring and outcome studies...... by the lack of centralized standardization procedures. In addition, data on outcomes and the cost of achieving them are needed in order to provide evidence of the beneficial effects of IDD prevention in countries with mild iodine deficiency. CONCLUSION: Monitoring studies can be optimized by including...... are needed to optimize the effectiveness of IDD prevention. SUMMARY: Although the need for monitoring is compelling, the current reality in Europe is less than optimal. Regular and systematic monitoring surveys have only been established in a few countries, and comparability across the studies is hampered...

  2. Urinary Iodine Clearance following Iodinated Contrast Administration: A Comparison of Euthyroid and Postthyroidectomy Subjects

    Directory of Open Access Journals (Sweden)

    Janice D. Ho

    2014-01-01

    Full Text Available Purpose. To compare iodine clearance following iodinated contrast administration in thyroidectomised thyroid cancer patients and euthyroid individuals. Methods. A convenience population (6 thyroidectomised thyroid cancer patients and 7 euthyroid controls was drawn from patients referred for iodinated contrast-enhanced computed tomography (CT studies. Subjects had sequential urine samples collected up to 6 months (50 samples from the thyroidectomised and 63 samples from the euthyroid groups. t-tests and generalised estimating equations (GEE were used to test for group differences in urinary iodine creatinine ratios. Results. Groups had similar urinary iodine creatinine ratios at baseline, with a large increase 2 weeks following iodinated contrast (P=0.005. Both groups had a return of urinary iodine creatinine ratios to baseline by 4 weeks, with no significant group differences overall or at any time point. Conclusions. Thyroidectomised patients did not have a significantly different urinary iodine clearance than euthyroid individuals following administration of iodinated contrast. Both had a return of urinary iodine creatinine ratios to baseline within 4 weeks.

  3. Current Iodine Nutrition Status and Awareness of Iodine Deficiency in Tuguegarao, Philippines

    Directory of Open Access Journals (Sweden)

    Bu Kyung Kim

    2014-01-01

    Full Text Available The Philippines is one of the countries where adequate iodine status has been achieved. However, iodine deficiency still remains an important public health problem in this country. In this study, we evaluated iodine nutrition status and investigated an awareness status of iodine deficiency targeting high school students of Tuguegarao, Philippines. A total of 260 students provided samples for urinary iodine analysis, among which 146 students completed thyroid volume measurement by ultrasonography and answering the questionnaires. The median urinary iodine level was 355.3 µg/L and only 3.8% of the students were in the range of iodine deficiency status according to the ICCIDD criteria. Although 62.3% of students answered that they can list problems resulting from iodine deficiency, a majority of students (70.5% were unable to identify problems other than goiter. They did not appreciate that adequate iodine levels are important during pregnancy and for development of children. 33.6% of students answered that they did not use iodized salt and the biggest reason was that they did not find it necessary. Based on these results, we suggest that a future strategy should be focused on vulnerable groups to completely eliminate iodine deficiency, including women at their reproductive ages and during pregnancy.

  4. Iodine nutrition in pregnant women from Oviedo area. Is iodine supplementation necessary?

    Science.gov (United States)

    Menéndez Torre, Edelmiro; Delgado Alvarez, Elías; Rabal Artal, Antonio; Suárez Gutiérrez, Lorena; Rodríguez Caballero, María Galiana; Ares Blanco, Jessica; Díaz Naya, Lucía; Fernández Fernández, Juan Carlos

    2014-10-01

    In Asturias, where iodine deficiency was eradicated in school children by the year 2000, iodine deficiency persisted in pregnant women, who were recommended to use of iodine supplementation. The aim of this study was to determine the iodine nutrition of pregnant women in our area and whether or not iodine supplements are needed. Throughout May and June 2013 we studied the iodine nutrition and thyroid function during the first trimester of pregnancy in 173 women in the health area of Oviedo. The median urinary iodine was 197 μg/L. Iodinated supplements were used by 47% of women, which had a yoduria median higher than those not taking iodinated supplements (247 vs. 138 μg/L; p<.001), and also a higher TSH (2.30 vs 1.94 mU/L) although not significantly different. Yoduria was also higher in women who took more than 2 servings of dairy products (median: 230 μg/L) than those who took less (median: 191 μg/L). Within the group of women who were not taking iodine supplements, those regularly using iodized salt in the kitchen (47%) had a median urinary iodine concentration of 190μg/L indicating iodine sufficiency. Iodinated supplements seem unnecessary nowadays in pregnant women of Oviedo who regularly take iodized salt and our recommendation in these cases should be to continue the use of iodized salt in the recommended amounts during pregnancy and consume at least two daily servings of milk or dairy products. Copyright © 2014 SEEN. Published by Elsevier Espana. All rights reserved.

  5. GenoGAM: genome-wide generalized additive models for ChIP-Seq analysis.

    Science.gov (United States)

    Stricker, Georg; Engelhardt, Alexander; Schulz, Daniel; Schmid, Matthias; Tresch, Achim; Gagneur, Julien

    2017-08-01

    Chromatin immunoprecipitation followed by deep sequencing (ChIP-Seq) is a widely used approach to study protein-DNA interactions. Often, the quantities of interest are the differential occupancies relative to controls, between genetic backgrounds, treatments, or combinations thereof. Current methods for differential occupancy of ChIP-Seq data rely however on binning or sliding window techniques, for which the choice of the window and bin sizes are subjective. Here, we present GenoGAM (Genome-wide Generalized Additive Model), which brings the well-established and flexible generalized additive models framework to genomic applications using a data parallelism strategy. We model ChIP-Seq read count frequencies as products of smooth functions along chromosomes. Smoothing parameters are objectively estimated from the data by cross-validation, eliminating ad hoc binning and windowing needed by current approaches. GenoGAM provides base-level and region-level significance testing for full factorial designs. Application to a ChIP-Seq dataset in yeast showed increased sensitivity over existing differential occupancy methods while controlling for type I error rate. By analyzing a set of DNA methylation data and illustrating an extension to a peak caller, we further demonstrate the potential of GenoGAM as a generic statistical modeling tool for genome-wide assays. Software is available from Bioconductor: https://www.bioconductor.org/packages/release/bioc/html/GenoGAM.html . gagneur@in.tum.de. Supplementary information is available at Bioinformatics online.

  6. Iodine supplementation in pregnancy and its effest on child cognition

    NARCIS (Netherlands)

    Boonstra, A.; Gowachirapant, S.; Jaiswal, A.K.; Winichagoon, P.; Srinivasan, K.; Zimmerman, M.B.

    2012-01-01

    Maternal hypothyroidism and hypothyroxenemia due to iodine deficiency have been shown to affect development of the newborn negatively. Maternal iodine supplementation may therefore improve cognitive performance of the offspring, even in areas of mild-to-moderate iodine deficiency (ID). Several iodin

  7. Iodine supplementation in pregnancy and its effest on child cognition

    NARCIS (Netherlands)

    Boonstra, A.; Gowachirapant, S.; Jaiswal, A.K.; Winichagoon, P.; Srinivasan, K.; Zimmerman, M.B.

    2012-01-01

    Maternal hypothyroidism and hypothyroxenemia due to iodine deficiency have been shown to affect development of the newborn negatively. Maternal iodine supplementation may therefore improve cognitive performance of the offspring, even in areas of mild-to-moderate iodine deficiency (ID). Several iodin

  8. Knowledge, attitudes and practices regarding iodine among patients ...

    African Journals Online (AJOL)

    Keywords: hyperthyroidism; iodine; iodised salt; knowledge-attitude-practice study; South Africa ... that IIH may occur even when the total amount of iodine intake is ... knowledge of iodine, as well as of the storage of iodised salt, and this could have ... the public, is recommended to ensure sustainable elimination of iodine ...

  9. Small organic molecules modulating iodine uptake in thyroid

    Energy Technology Data Exchange (ETDEWEB)

    Ambroise, Y. [CEA Saclay, DSV/DBJC/SMMCB, 91 - Gif-sur-Yvette (France)

    2006-07-01

    The thyroid gland accumulates large quantities of iodine. This uptake is needed for the production of iodinated hormones (T3 and T4). The first step in the iodine accumulation is a basolateral transport of iodide ions by the cloned 'Natrium Iodide Sym-porter' also called NIS. Using high-throughput screening techniques, we have identified a series of inhibitors of the iodide uptake in thyrocytes. These compounds are of medical significance in case of thyroid deregulation and can also offer solutions for radio-iodine detoxification in case of emergency situations (nuclear industry...). In addition, these small organic molecules can be important tools for the understanding of NIS structure and functions In parallel, we have identified and characterized a single compound capable to strongly enhance the amount of intra-cellular iodide in rat thyrocytes (FRTL5) as well as in HEK293 cells transfected with hNIS (Natrium/Iodide Sym-porter). Preliminary studies show that this effect is NIS dependant, and is induced by alternative and unknown mechanisms. Future work will consist in unraveling the mode of action of this molecule. These informations will help us not only to better understand the iodide pathways in the thyroid, but also to design more active analogues. We will use photo-labelling techniques to identify new proteins involved in the iodide transfer and retention. In addition, preliminary experiments are underway to validate our compound as an anti-cancer agent. Targeted NIS gene delivery into tumors plus radio-iodide injection leads to tumor size regression. Unfortunately, doses of radioactivity are to high for safe treatment. Our compound may lead to enhanced radio-iodide entrapment, thus necessitating lower doses of radioactivity for tumor regression. (author)

  10. Reduced radioiodine uptake at increased iodine intake and {sup 131}I-induced release of ''cold'' iodine stored in the thyroid

    Energy Technology Data Exchange (ETDEWEB)

    Meller, B.; Haase, A.; Richter, E.; Baehre, M. [Dept. of Radiotherapy and Nuclear Medicine, Univ. of Luebeck (Germany); Seyfarth, M. [Inst. of Clinical Chemistry, Univ. of Luebeck (Germany); Wenzel, B.E. [Clinic of Internal Medicine I, Univ. of Luebeck (Germany)

    2005-07-01

    Aim: the extent of urinary iodine excretion (UIE) provides information about iodine supply and release. In the present study we investigated correlations between UIE and radioiodine uptake (RIU) as well as effects of radioiodine therapy on UIE in patients with autonomous goitre. Patients, methods: In 197 consecutive patients with thyroid autonomy, UIE was measured twice during radioiodine test (RITe) and correlated with RIU. In 98 of these patients, thyroglobulin and thyroid volume (V) were determined prior to therapy. Individual changes in urinary iodine excretion ({delta}UIE) and TG ({delta}TG) could be investigated four weeks (4W) and six months (6M) after radioiodine therapy. Additionally, {delta}V was determined 6M after therapy. {delta}UIE, {delta}TG and {delta}V were correlated with target dose and target volume. Results: patients with higher iodine excretion exhibited significantly lower thyroidal radioiodine uptake values. Twofold increased UIE prior to therapy decreased radioiodine uptake by 25%. Compared with pretherapeutic values, UIE and TG were significantly increased four weeks after radioiodine therapy (p < 0.001). Median values of both parameters were found to be doubled. The product of target dose and target volume was not only correlated with a decrease of thyroid volume 6M after therapy, but also with an increase of UIE and TG in the early phase after therapy. Conclusions: it was confirmed that UIE during RITe is a measure for iodine intake and can be used to investigate the competition between stable iodine and radioiodine. The increase of UIE and TG four weeks after therapeutic administration of radioiodine can be explained by disintegrated thyroid follicles. The therapy-induced iodine release may be one important cause for the development of hyperthyroidism in some patients during the first weeks after radioiodine therapy. It may contribute to the known decrease of radioiodine uptake after preapplications of {sup 131}I in various thyroid

  11. Reduction of carcinogenic 4(5)-methylimidazole in a caramel model system: influence of food additives.

    Science.gov (United States)

    Seo, Seulgi; Ka, Mi-Hyun; Lee, Kwang-Geun

    2014-07-09

    The effect of various food additives on the formation of carcinogenic 4(5)-methylimidazole (4-MI) in a caramel model system was investigated. The relationship between the levels of 4-MI and various pyrazines was studied. When glucose and ammonium hydroxide were heated, the amount of 4-MI was 556 ± 1.3 μg/mL, which increased to 583 ± 2.6 μg/mL by the addition of 0.1 M of sodium sulfite. When various food additives, such as 0.1 M of iron sulfate, magnesium sulfate, zinc sulfate, tryptophan, and cysteine were added, the amount of 4-MI was reduced to 110 ± 0.7, 483 ± 2.0, 460 ± 2.0, 409 ± 4.4, and 397 ± 1.7 μg/mL, respectively. The greatest reduction, 80%, occurred with the addition of iron sulfate. Among the 12 pyrazines, 2-ethyl-6-methylpyrazine with 4-MI showed the highest correlation (r = -0.8239).

  12. Effect of maternal excessive iodine intake on neurodevelopment and cognitive function in rat offspring

    Directory of Open Access Journals (Sweden)

    Zhang Le

    2012-10-01

    Full Text Available Abstract Background Iodine deficiency and iodine excess are both associated with adverse health consequences. Iodine deficiency during pregnancy leads to insufficient maternal thyroid hormone, subsequently causing irreversible adverse effects on the neurological and cognitive functions of the offspring. The results of our previous epidemiological study suggested that mild iodine excess might increase the prevalence of subclinical hypothyroidism. In the present study, female Wistar rats maintained on low-iodine grain were randomly assigned to three groups based on iodated water concentration: low iodine (LI, 1.2 μg/d, normal iodine (NI, 5–6 μg/d, and 3-fold high iodine (3HI, 15–16 μg/d. The present study investigated whether higher-than-normal iodine intake (3HI by rats from before pregnancy until breastfeeding affects the postnatal (PN neurodevelopment (PN7 and PN45 of their offspring during particularly sensitive periods in brain development. Results After 12 weeks of treatment (before pregnancy, iodine concentrations in urine and thyroid tissue and circulating thyroxine of adult females correlated with iodine intake. Brain-derived neurotrophic factor (BDNF expression in the hippocampi of pups on PN7 and PN45 was decreased in 3HI group compared to the NI controls (P  0.05, all On PN7 and PN45, the BDNF levels of the 3HI pups were 83.5% and 88.8%, respectively, that of the NI pups. In addition, the 3HI group had a higher neuroendocrine-specific protein A (NSP-A level than the NI controls on PN7 (P  0.05. NSP-A levels of the 3HI pups were 117.0% that of the NI pups. No significant difference was observed in the expressions of c-Fos or c-Jun in the hippocampal CA1 region of the 3HI group compared to the controls (P > 0.05. Results from the Morris water maze test revealed that pups of the 3HI group had mild learning and spatial memory deficits. Conclusions The neurodevelopmental and cognitive deficits of the 3HI pups were

  13. Present status of iodine research at IPSN

    Energy Technology Data Exchange (ETDEWEB)

    Bardelay, J. [IPSN/DPEA/SEAC (France)

    1996-12-01

    Since several years, IPSN has conducted an effort in order to evaluate the release of radioactive iodine in case of hypothetical severe accident in a realistic manner. This source-term evaluation is performed with IODE code which is a module of the EXCADRE system of codes. This code is validated against: -analytical experiments: in these experiments, IPSN studies radiolytic effects and chemical processes in the sump, organic formation, mass transfer, effect of spray (CARAIDAS experiment), - the CAIMAN semi global experiment; this experiment will allow to study the phenomena linked to iodine behavior under representative containment geometry in the presence of painted surfaces and global irradiation, - the PHEBUS FP program. The paper consists to describe succinctly the current status of IODE and the various experiments for its validation. In case of hypothetical severe accident iodine can induce important perturbations of human organism. The effects are principally radiological, in particular on the thyroid. At short term, radioactive iodine is the most important contributor for the sanitary risk. It represents 55% of effective dose and 92% of thyroid dose at 10 km in case of controlled rejects with current assumptions. This is the reason why it must be actively studied. In France, the safety evaluations are performed with mechanistic codes or lumped parameter codes like EXCADRE which contains a module devoted to iodine studies: IODINE. The objective of the French experimental program on iodine is to understand and quantify important phenomena in order to put kinetic parameters in IODE module. The experiments can be classified in analytical experiments, the semi-global experiment CAIMAN which takes into account different phenomena studied in analytical experiments and the global experiment PHEBUS PF, not only devoted to iodine behavior study. In the following text we will present the needs of IODINE code and these different experiments. (author).

  14. Minimax-optimal rates for sparse additive models over kernel classes via convex programming

    CERN Document Server

    Raskutti, Garvesh; Yu, Bin

    2010-01-01

    Sparse additive models are families of $d$-variate functions that have the additive decomposition \\mbox{$f^* = \\sum_{j \\in S} f^*_j$,} where $S$ is a unknown subset of cardinality $s \\ll d$. We consider the case where each component function $f^*_j$ lies in a reproducing kernel Hilbert space, and analyze a simple kernel-based convex program for estimating the unknown function $f^*$. Working within a high-dimensional framework that allows both the dimension $d$ and sparsity $s$ to scale, we derive convergence rates in the $L^2(\\mathbb{P})$ and $L^2(\\mathbb{P}_n)$ norms. These rates consist of two terms: a \\emph{subset selection term} of the order $\\frac{s \\log d}{n}$, corresponding to the difficulty of finding the unknown $s$-sized subset, and an \\emph{estimation error} term of the order $s \\, \

  15. Utilization of sulfate additives in biomass combustion: fundamental and modeling aspects

    DEFF Research Database (Denmark)

    Wu, Hao; Jespersen, Jacob Boll; Grell, Morten Nedergaard;

    2013-01-01

    Sulfates, such as ammonium sulfate, aluminum sulfate and ferric sulfate, are effective additives for converting the alkali chlorides released from biomass combustion to the less harmful alkali sulfates. Optimization of the use of these additives requires knowledge on their decomposition rate...... and product distribution under high temperature conditions. In the present work, the decomposition of ammonium sulfate, aluminum sulfate and ferric sulfate was studied respectively in a fast-heating rate thermogravimetric analyzer for deriving a kinetic model to describe the process. The yields of SO2 and SO3...... of different sulfates indicated that ammonium sulfate has clearly strongest sulfation power towards KCl at temperatures below 800oC, whereas the sulfation power of ferric and aluminum sulfates exceeds clearly that of ammonium sulfate between 900 and 1000oC. However, feeding gaseous SO3 was found to be most...

  16. Analysis of time to event outcomes in randomized controlled trials by generalized additive models.

    Directory of Open Access Journals (Sweden)

    Christos Argyropoulos

    Full Text Available Randomized Controlled Trials almost invariably utilize the hazard ratio calculated with a Cox proportional hazard model as a treatment efficacy measure. Despite the widespread adoption of HRs, these provide a limited understanding of the treatment effect and may even provide a biased estimate when the assumption of proportional hazards in the Cox model is not verified by the trial data. Additional treatment effect measures on the survival probability or the time scale may be used to supplement HRs but a framework for the simultaneous generation of these measures is lacking.By splitting follow-up time at the nodes of a Gauss Lobatto numerical quadrature rule, techniques for Poisson Generalized Additive Models (PGAM can be adopted for flexible hazard modeling. Straightforward simulation post-estimation transforms PGAM estimates for the log hazard into estimates of the survival function. These in turn were used to calculate relative and absolute risks or even differences in restricted mean survival time between treatment arms. We illustrate our approach with extensive simulations and in two trials: IPASS (in which the proportionality of hazards was violated and HEMO a long duration study conducted under evolving standards of care on a heterogeneous patient population.PGAM can generate estimates of the survival function and the hazard ratio that are essentially identical to those obtained by Kaplan Meier curve analysis and the Cox model. PGAMs can simultaneously provide multiple measures of treatment efficacy after a single data pass. Furthermore, supported unadjusted (overall treatment effect but also subgroup and adjusted analyses, while incorporating multiple time scales and accounting for non-proportional hazards in survival data.By augmenting the HR conventionally reported, PGAMs have the potential to support the inferential goals of multiple stakeholders involved in the evaluation and appraisal of clinical trial results under proportional and

  17. Effect of chronic douching with polyvinylpyrrolidone-iodine on iodine absorption and thyroid function

    Energy Technology Data Exchange (ETDEWEB)

    Safran, M.; Braverman, L.E.

    1982-07-01

    Daily vaginal douching with polyvinylpyrrolidone-iodine in 12 euthyroid volunteers for 14 days resulted in a significant increase in serum total iodine concentration and urine iodine excretion. The increase in serum total iodine was associated with a marked decrease in 24-hour /sup 123/I uptake by the thyroid and a small but significant increase in serum thyrotropin (TSH) concentration. However, values for serum TSH never rose above the normal range. No significant changes in serum thyroxine (T4), free T4 index (FTI), or triiodothyronine concentrations were observed, although serum T4 and FTI did decrease slightly during treatment. The findings suggest that iodine is absorbed across the vaginal mucosa and that the subsequent increase in serum total iodine does induce subtle increases in serum TSH concentration. There was no evidence, however, of overt hypothyroidism in these euthyroid women.

  18. IODINATION OF VEGETABLE OIL AS A METHOD FOR CORRECTING IODINE DEFFICIENCY

    Directory of Open Access Journals (Sweden)

    Rodica Sturza

    2006-06-01

    Full Text Available The aim of this work is the study made for obtaining iodized oil that would satisfy the requirements in iodine for human body. The sunflower oil is a product with the most important value, thus the production of oil fortified with iodine would be a cheap and accessible option. These studies indicate that lipids present an important vehicle for the fortification with iodine. Eradication of the iodine deficiency may be realized not only by injection of the iodinated oil, but also by its use as an ingredient for the formulation of different food compositions. This method, complementary with the iodinated salt, would allow the increase of the efficiency of the prophylactic undertaken measures, because is based on the use of vegetal material – sunflower oil; it is cost-efficient and does not require substantial investments.

  19. Topsoil organic carbon content of Europe, a new map based on a generalised additive model

    Science.gov (United States)

    de Brogniez, Delphine; Ballabio, Cristiano; Stevens, Antoine; Jones, Robert J. A.; Montanarella, Luca; van Wesemael, Bas

    2014-05-01

    There is an increasing demand for up-to-date spatially continuous organic carbon (OC) data for global environment and climatic modeling. Whilst the current map of topsoil organic carbon content for Europe (Jones et al., 2005) was produced by applying expert-knowledge based pedo-transfer rules on large soil mapping units, the aim of this study was to replace it by applying digital soil mapping techniques on the first European harmonised geo-referenced topsoil (0-20 cm) database, which arises from the LUCAS (land use/cover area frame statistical survey) survey. A generalized additive model (GAM) was calibrated on 85% of the dataset (ca. 17 000 soil samples) and a backward stepwise approach selected slope, land cover, temperature, net primary productivity, latitude and longitude as environmental covariates (500 m resolution). The validation of the model (applied on 15% of the dataset), gave an R2 of 0.27. We observed that most organic soils were under-predicted by the model and that soils of Scandinavia were also poorly predicted. The model showed an RMSE of 42 g kg-1 for mineral soils and of 287 g kg-1 for organic soils. The map of predicted OC content showed the lowest values in Mediterranean countries and in croplands across Europe, whereas highest OC content were predicted in wetlands, woodlands and in mountainous areas. The map of standard error of the OC model predictions showed high values in northern latitudes, wetlands, moors and heathlands, whereas low uncertainty was mostly found in croplands. A comparison of our results with the map of Jones et al. (2005) showed a general agreement on the prediction of mineral soils' OC content, most probably because the models use some common covariates, namely land cover and temperature. Our model however failed to predict values of OC content greater than 200 g kg-1, which we explain by the imposed unimodal distribution of our model, whose mean is tilted towards the majority of soils, which are mineral. Finally, average

  20. Improving the predictive accuracy of hurricane power outage forecasts using generalized additive models.

    Science.gov (United States)

    Han, Seung-Ryong; Guikema, Seth D; Quiring, Steven M

    2009-10-01

    Electric power is a critical infrastructure service after hurricanes, and rapid restoration of electric power is important in order to minimize losses in the impacted areas. However, rapid restoration of electric power after a hurricane depends on obtaining the necessary resources, primarily repair crews and materials, before the hurricane makes landfall and then appropriately deploying these resources as soon as possible after the hurricane. This, in turn, depends on having sound estimates of both the overall severity of the storm and the relative risk of power outages in different areas. Past studies have developed statistical, regression-based approaches for estimating the number of power outages in advance of an approaching hurricane. However, these approaches have either not been applicable for future events or have had lower predictive accuracy than desired. This article shows that a different type of regression model, a generalized additive model (GAM), can outperform the types of models used previously. This is done by developing and validating a GAM based on power outage data during past hurricanes in the Gulf Coast region and comparing the results from this model to the previously used generalized linear models.

  1. Thyroid disorders in mild iodine deficiency

    DEFF Research Database (Denmark)

    Laurberg, P; Nøhr, S B; Pedersen, K M

    2000-01-01

    in elderly subjects, especially women, with risk of cardiac arrhythmias, osteoporosis, and muscle wasting. The hyperthyroidism is caused by autonomous nodular growth and function of the thyroid gland and it is accompanied by a high frequency of goiter. Pregnant women and small children are not immediately......Comparative epidemiologic studies in areas with low and high iodine intake and controlled studies of iodine supplementation have demonstrated that the major consequence of mild-to-moderate iodine deficiency for the health of the population is an extraordinarily high occurrence of hyperthyroidism...

  2. Iodine Supplementation: Usage “with a Grain of Salt”

    OpenAIRE

    Alessandro Prete; Rosa Maria Paragliola; Salvatore Maria Corsello

    2015-01-01

    Iodine supplementation through salt iodization is a worldwide, effective strategy for preventing iodine deficiency-related problems. Its safety and efficacy profile has been extensively investigated, and benefits far outweigh the potential iodine-induced risks. Moreover, iodine supplementation during pregnancy in order to avoid brain damage in the newborn is considered a mainstay of preventive medicine. Exposure to high amounts of iodine is actually well tolerated in most cases and can be unr...

  3. Metabolic engineering of the iodine content in Arabidopsis

    OpenAIRE

    Martina Landini; Silvia Gonzali; Claudia Kiferle; Massimo Tonacchera; Patrizia Agretti; Antonio Dimida; Paolo Vitti; Amedeo Alpi; Aldo Pinchera; Pierdomenico Perata

    2012-01-01

    Plants are a poor source of iodine, an essential micronutrient for human health. Several attempts of iodine biofortification of crops have been carried out, but the scarce knowledge on the physiology of iodine in plants makes results often contradictory and not generalizable. In this work, we used a molecular approach to investigate how the ability of a plant to accumulate iodine can be influenced by different mechanisms. In particular, we demonstrated that the iodine content in Arabidopsis t...

  4. Analysis of two-phase sampling data with semiparametric additive hazards models.

    Science.gov (United States)

    Sun, Yanqing; Qian, Xiyuan; Shou, Qiong; Gilbert, Peter B

    2017-07-01

    Under the case-cohort design introduced by Prentice (Biometrica 73:1-11, 1986), the covariate histories are ascertained only for the subjects who experience the event of interest (i.e., the cases) during the follow-up period and for a relatively small random sample from the original cohort (i.e., the subcohort). The case-cohort design has been widely used in clinical and epidemiological studies to assess the effects of covariates on failure times. Most statistical methods developed for the case-cohort design use the proportional hazards model, and few methods allow for time-varying regression coefficients. In addition, most methods disregard data from subjects outside of the subcohort, which can result in inefficient inference. Addressing these issues, this paper proposes an estimation procedure for the semiparametric additive hazards model with case-cohort/two-phase sampling data, allowing the covariates of interest to be missing for cases as well as for non-cases. A more flexible form of the additive model is considered that allows the effects of some covariates to be time varying while specifying the effects of others to be constant. An augmented inverse probability weighted estimation procedure is proposed. The proposed method allows utilizing the auxiliary information that correlates with the phase-two covariates to improve efficiency. The asymptotic properties of the proposed estimators are established. An extensive simulation study shows that the augmented inverse probability weighted estimation is more efficient than the widely adopted inverse probability weighted complete-case estimation method. The method is applied to analyze data from a preventive HIV vaccine efficacy trial.

  5. Mixed butanols addition to gasoline surrogates: Shock tube ignition delay time measurements and chemical kinetic modeling

    KAUST Repository

    AlRamadan, Abdullah S.

    2015-10-01

    The demand for fuels with high anti-knock quality has historically been rising, and will continue to increase with the development of downsized and turbocharged spark-ignition engines. Butanol isomers, such as 2-butanol and tert-butanol, have high octane ratings (RON of 105 and 107, respectively), and thus mixed butanols (68.8% by volume of 2-butanol and 31.2% by volume of tert-butanol) can be added to the conventional petroleum-derived gasoline fuels to improve octane performance. In the present work, the effect of mixed butanols addition to gasoline surrogates has been investigated in a high-pressure shock tube facility. The ignition delay times of mixed butanols stoichiometric mixtures were measured at 20 and 40bar over a temperature range of 800-1200K. Next, 10vol% and 20vol% of mixed butanols (MB) were blended with two different toluene/n-heptane/iso-octane (TPRF) fuel blends having octane ratings of RON 90/MON 81.7 and RON 84.6/MON 79.3. These MB/TPRF mixtures were investigated in the shock tube conditions similar to those mentioned above. A chemical kinetic model was developed to simulate the low- and high-temperature oxidation of mixed butanols and MB/TPRF blends. The proposed model is in good agreement with the experimental data with some deviations at low temperatures. The effect of mixed butanols addition to TPRFs is marginal when examining the ignition delay times at high temperatures. However, when extended to lower temperatures (T < 850K), the model shows that the mixed butanols addition to TPRFs causes the ignition delay times to increase and hence behaves like an octane booster at engine-like conditions. © 2015 The Combustion Institute.

  6. Micellar Effects on Nucleophilic Addition Reaction and Applicability of Enzyme Catalysis Model

    Directory of Open Access Journals (Sweden)

    R. K. London Singh

    2012-01-01

    Full Text Available This study describes the effect of anionic and cationic micelles on nucleophilic addition reaction of rosaniline hydrochloride (RH with hydroxide under pseudo-first order condition. Strong inhibitory effect is observed due to SDS micelle, whereas CTAB catalysed the reaction. This is explained on the basis of electrostatic and hydrophobic interactions which are simultaneously operating in the reaction system. The kinetic data obtained is quantitatively analysed by applying the positive cooperativity model of enzyme catalysis. Binding constants and influence of counterions on the reaction have also been investigated.

  7. An Empirical Research on the Model of the Right in Additional Allocation of Stocks

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    How to define the value of the Right in Additional Al location of Stocks (RAAS) acts an important role in stock markets whether or not the shareholders execute the right. Moreover, the valuation defining of RAAS an d the exercise price (K) are mutual cause and effect. Based on some literatures on this subject, this paper presents a model valuing the RAAS per-share. With t he opening information in ShenZheng Stock Markets, we make a simulation on the R AAS's value of shenwuye, which is a shareholding corp...

  8. Iodine-131 releases from the Hanford Site, 1944--1947

    Energy Technology Data Exchange (ETDEWEB)

    Heeb, C.M.

    1992-10-01

    Detailed results of the Hanford Environmental Dose Reconstruction (HEDR) iodine-131 release reconstruction are presented in this volume. Included are daily data on B, D, and F Plant, reactor operations from the P-Department Daily Reports (General Electric Company 1947). Tables of B and T Plant material processed from the three principal sources on separations plant operations: The Jaech report (Jaech undated), the 200 Area Report (Acken and Bird 1945; Bird and Donihee 1945), and the Metal History Reports (General Electric Company 1946). A transcription of the Jaech report is also provided because it is computer-generated and is not readily readable in its original format. The iodine-131 release data are from the STRM model. Cut-by-cut release estimates are provided, along with daily, monthly, and yearly summations. These summations are based on the hourly release estimates. The hourly data are contained in a 28 megabyte electronic file. Interested individuals may request a copy.

  9. Iodine-131 releases from the Hanford Site, 1944--1947

    Energy Technology Data Exchange (ETDEWEB)

    Heeb, C.M.

    1993-03-01

    Detailed results of the Hanford Environmental Dose Reconstruction project (HEDR) iodine-131 release reconstruction are presented in this volume. Included are daily data on B, D, and F Plant, reactor operations from the P-Department Daily Reports (General Electric Company 1947). Tables of B and T Plant material processed from the three principal sources on separations plant operations: The Jaech report (Jaech undated), the 200 Area Report (Acken and Bird 1945; Bird and Donihee 1945), and the Metal History Reports (General Electric Company 1946). A transcription of the Jaech report is also provided because it is computer-generated and is not readily readable in its original format. The iodine-131 release data are from the STRM model. Cut-by-cut release estimates are provided, along with daily, monthly, and yearly summations. These summations are based on the hourly release estimates. The hourly data are contained in a 28 megabyte electronic file. Interested individuals may request a copy.

  10. A Spectral Analysis of Laser Induced Fluorescence of Iodine

    CERN Document Server

    Bayram, S B

    2015-01-01

    When optically excited, iodine absorbs in the 490- to 650-nm visible region of the spectrum and, after radiative relaxation, it displays an emission spectrum of discrete vibrational bands at moderate resolution. This makes laser-induced fuorescence spectrum of molecular iodine especially suitable to study the energy structure of homonuclear diatomic molecules at room temperature. In this spirit, we present a rather straightforward and inexpensive experimental setup and the associated spectral analysis which provides an excellent exercise of applied quantum mechanics fit for advanced laboratory courses. The students would be required to assign spectral lines, fill a Deslandres table, process the data to estimate the harmonic and anharmonic characteristics of the ground vibronic state involved in the radiative transitions, and thenceforth calculate a set of molecular constants and discuss a model of molecular vibrator.

  11. Dietary Iodine Intake of the Australian Population after Introduction of a Mandatory Iodine Fortification Programme

    OpenAIRE

    Karen Charlton; Yasmine Probst; Gabriella Kiene

    2016-01-01

    To address mild iodine deficiency in Australia, a mandatory fortification program of iodised salt in bread was implemented in 2009. This study aimed to determine factors associated with achieving an adequate dietary iodine intake in the Australian population post-fortification, and to assess whether bread consumption patterns affect iodine intake in high-risk groups. Using nationally representative data of repeated 24-h dietary recalls from the 2011–2012 Australian National Nutrition and Phys...

  12. Analysis of iodine content in seaweed by GC-ECD and estimation of iodine intake

    Directory of Open Access Journals (Sweden)

    Tai Sheng Yeh

    2014-06-01

    Full Text Available Edible seaweed products have been consumed in many Asian countries. Edible seaweeds accumulate iodine from seawater, and are therefore a good dietary source of iodine. An adequate consumption of seaweed can eliminate iodine deficiency disorders, but excessive iodine intake is not good for health. The recommended dietary reference intake of 0.15 mg/d and 0.14 mg/d for iodine has been established in the United States and Taiwan, respectively. In this study, 30 samples of seaweed were surveyed for iodine content. The samples included 10 nori (Porphyra, 10 wakame (Undaria, and 10 kombu (Laminaria products. The iodine in seaweed was derivatized with 3-pentanone and detected by gas chromatography-electron capture detector (GC-ECD. The method detection limit was 0.5 mg/kg. The iodine content surveyed for nori was 29.3–45.8 mg/kg, for wakame 93.9–185.1 mg/kg, and for kombu 241–4921 mg/kg. Kombu has the highest average iodine content 2523.5 mg/kg, followed by wakame (139.7 mg/kg and nori (36.9 mg/kg. The GC-ECD method developed in this study is a low-cost alternative to inductively coupled plasma-optical emission spectroscopy for iodine detection in seaweeds. The iodine intake from seaweed in the current survey was calculated and compared with the iodine dietary reference intake of Taiwan. The risk and benefit of seaweed consumption is also discussed.

  13. An iodine-based frequency reference for space applications

    Science.gov (United States)

    Schuldt, Thilo; Johann, Ulrich; Doeringshoff, Klaus; Kovalchuk, Evgeny; Peters, Achim; Braxmaier, Claus; Pahl, Julia; Stuehler, Johannes; Franz, Matthias

    We present the development of an iodine-based frequency reference for future potential applications in space, including the gravitational wave detector LISA/eLISA (Laser Interferometer Space Antenna), the mini SpaceTime Asymmetry Research (mSTAR) program, the aperture-synthesis telescope Darwin and the GRACE (Gravity Recovery and Climate Experiment) follow on mission/NGGM (Next Generation Gravity Mission) exploring Earth's gravity. Based on a state-of-the-art laboratory iodine frequency reference, setups on elegant breadboard (EBB) and engineering model (EM) level were realized, taking into account specific design criteria for space compatibility such as compactness and robustness. Both setups employ modulation transfer spectroscopy (MTS) in combination with balanced detection. They use a baseplate made of glass material in combination with a dedicated easy-to-handle assembly-integration technology (adhesive bonding) ensuring high pointing stability of the two counter-propagating laser beams in the iodine cell and therefore high long-term stability. The EBB setup utilizes a commercial off-the-shelf 30 cm long iodine cell in triple-pass configuration, the EM setup a specifically designed and manufactured compact iodine cell made of fused silica in a nine-pass configuration with a specific robust cold finger design. Both setups were characterized in beat measurements with a ULE cavity setup. Similar frequency stabilities of about 1*10 (-14) at an integration time of 1 s and below 5*10 (-15) at integration times between 10 s and 100 s were demonstrated. These values are comparable to the currently best laboratory setups. The EM setup was further subjected to environmental testing including thermal cycling and vibrational testing. Financial support by the German Space Agency DLR with funds provided by the Federal Ministry of Economics and Technology (BMWi) under grant numbers 50 QT 1102 and 50 QT 1201 is highly appreciated. The authors thank Jan Hrabina and Josef Lazar

  14. Low dose radiation risks for women surviving the a-bombs in Japan: generalized additive model.

    Science.gov (United States)

    Dropkin, Greg

    2016-11-24

    Analyses of cancer mortality and incidence in Japanese A-bomb survivors have been used to estimate radiation risks, which are generally higher for women. Relative Risk (RR) is usually modelled as a linear function of dose. Extrapolation from data including high doses predicts small risks at low doses. Generalized Additive Models (GAMs) are flexible methods for modelling non-linear behaviour. GAMs are applied to cancer incidence in female low dose subcohorts, using anonymous public data for the 1958 - 1998 Life Span Study, to test for linearity, explore interactions, adjust for the skewed dose distribution, examine significance below 100 mGy, and estimate risks at 10 mGy. For all solid cancer incidence, RR estimated from 0 - 100 mGy and 0 - 20 mGy subcohorts is significantly raised. The response tapers above 150 mGy. At low doses, RR increases with age-at-exposure and decreases with time-since-exposure, the preferred covariate. Using the empirical cumulative distribution of dose improves model fit, and capacity to detect non-linear responses. RR is elevated over wide ranges of covariate values. Results are stable under simulation, or when removing exceptional data cells, or adjusting neutron RBE. Estimates of Excess RR at 10 mGy using the cumulative dose distribution are 10 - 45 times higher than extrapolations from a linear model fitted to the full cohort. Below 100 mGy, quasipoisson models find significant effects for all solid, squamous, uterus, corpus, and thyroid cancers, and for respiratory cancers when age-at-exposure > 35 yrs. Results for the thyroid are compatible with studies of children treated for tinea capitis, and Chernobyl survivors. Results for the uterus are compatible with studies of UK nuclear workers and the Techa River cohort. Non-linear models find large, significant cancer risks for Japanese women exposed to low dose radiation from the atomic bombings. The risks should be reflected in protection standards.

  15. A prototype of an electric-discharge gas flow oxygen−iodine laser: I. Modeling of the processes of singlet oxygen generation in a transverse cryogenic slab RF discharge

    Energy Technology Data Exchange (ETDEWEB)

    Vagin, N. P.; Ionin, A. A., E-mail: aion@sci.lebedev.ru; Kochetov, I. V.; Napartovich, A. P.; Sinitsyn, D. V., E-mail: dsinit@sci.lebedev.ru; Yuryshev, N. N. [Russian Academy of Sciences, Lebedev Physical Institute (Russian Federation)

    2017-03-15

    The existing kinetic model describing self-sustained and electroionization discharges in mixtures enriched with singlet oxygen has been modified to calculate the characteristics of a flow RF discharge in molecular oxygen and its mixtures with helium. The simulations were performed in the gas plug-flow approximation, i.e., the evolution of the plasma components during their motion along the channel was represented as their evolution in time. The calculations were carried out for the O{sub 2}: He = 1: 0, 1: 1, 1: 2, and 1: 3 mixtures at an oxygen partial pressure of 7.5 Torr. It is shown that, under these conditions, volumetric gas heating in a discharge in pure molecular oxygen prevails over gas cooling via heat conduction even at an electrode temperature as low as ~100 K. When molecular oxygen is diluted with helium, the behavior of the gas temperature changes substantially: heat removal begins to prevail over volumetric gas heating, and the gas temperature at the outlet of the discharge zone drops to ~220–230 K at room gas temperature at the inlet, which is very important in the context of achieving the generation threshold in an electric-discharge oxygen−iodine laser based on a slab cryogenic RF discharge.

  16. Effect of lactoperoxidase-catalyzed iodination on the Ca sub 2+ -dependent interactions of human C anti 1 s. Location of the iodination sites

    Energy Technology Data Exchange (ETDEWEB)

    Illy, C.; Thielens, N.M.; Gagnon, J.; Arlaud, G.J. (Centre d' Etudes Nucleaires de Grenoble (France))

    1991-07-23

    C{anti 1}s, one of the two serine proteases of C{anti 1}, the first component of complement has the ability to mediate heterologous (C{anti 1}r-C{anti 1}s) as well as homologous (C{anti 1}s-C{anti 1}s) Ca{sup 2+}-dependent interactions, both involving the NH{sub 2}-terminal {alpha} region of its A chain. Lactoperoxidase-catalyzed iodination of C{anti 1}s in its monomeric form was found to abolish its ability to form Ca{sup 2+}-dependent homodimers, without impairing its ability to mediate C{anti 1}r-C{anti 1}s heteroassociation. C{anti 1}s iodinated in its dimeric form in contrast, fully retained the ability to self-associate. With a view to identify the tyrosine residues iodinated in each case, C{anti 1}s was radioiodinated in its monomeric and dimeric forms, and comparative tryptic mapping was performed on the resulting {sup 125}I-labeled A chains. Most of the tyrosine residues either were not iodinated or were equivalently iodinated in both monomeric and dimeric C{anti 1}s. In contrast, Tyr-33 and Tyr-38 were iodinated in the monomer but not in the dimer. Conversely, Try-52 and Tyr-147 were iodinated only in the dimer. These results provide further evidence that the structural determinants of C{anti 1}s required for Ca{sup 2+} binding and Ca{sup 2+}-dependent protein-protein interactions are contributed by both the NH{sub 2}-terminal motif 1 (positions 1-110) and the epidermal growth factor like motif 2 (positions 111-159) of the {alpha} region. On the basis of available information, tentative models of the C{anti 1}s-C{anti 1}S and C{anti 1}r-C{anti 1}s Ca{sup 2+}-dependent interactions are proposed.

  17. Hybrid 2D-3D modelling of GTA welding with filler wire addition

    KAUST Repository

    Traidia, Abderrazak

    2012-07-01

    A hybrid 2D-3D model for the numerical simulation of Gas Tungsten Arc welding is proposed in this paper. It offers the possibility to predict the temperature field as well as the shape of the solidified weld joint for different operating parameters, with relatively good accuracy and reasonable computational cost. Also, an original approach to simulate the effect of immersing a cold filler wire in the weld pool is presented. The simulation results reveal two important observations. First, the weld pool depth is locally decreased in the presence of filler metal, which is due to the energy absorption by the cold feeding wire from the hot molten pool. In addition, the weld shape, maximum temperature and thermal cycles in the workpiece are relatively well predicted even when a 2D model for the arc plasma region is used. © 2012 Elsevier Ltd. All rights reserved.

  18. Generalized additive models and Lucilia sericata growth: assessing confidence intervals and error rates in forensic entomology.

    Science.gov (United States)

    Tarone, Aaron M; Foran, David R

    2008-07-01

    Forensic entomologists use blow fly development to estimate a postmortem interval. Although accurate, fly age estimates can be imprecise for older developmental stages and no standard means of assigning confidence intervals exists. Presented here is a method for modeling growth of the forensically important blow fly Lucilia sericata, using generalized additive models (GAMs). Eighteen GAMs were created to predict the extent of juvenile fly development, encompassing developmental stage, length, weight, strain, and temperature data, collected from 2559 individuals. All measures were informative, explaining up to 92.6% of the deviance in the data, though strain and temperature exerted negligible influences. Predictions made with an independent data set allowed for a subsequent examination of error. Estimates using length and developmental stage were within 5% of true development percent during the feeding portion of the larval life cycle, while predictions for postfeeding third instars were less precise, but within expected error.

  19. On adjustment for auxiliary covariates in additive hazard models for the analysis of randomized experiments

    DEFF Research Database (Denmark)

    Vansteelandt, S.; Martinussen, Torben; Tchetgen, E. J Tchetgen

    2014-01-01

    's dependence on time or on the auxiliary covariates is misspecified, and even away from the null hypothesis of no treatment effect. We furthermore show that adjustment for auxiliary baseline covariates does not change the asymptotic variance of the estimator of the effect of a randomized treatment. We conclude......We consider additive hazard models (Aalen, 1989) for the effect of a randomized treatment on a survival outcome, adjusting for auxiliary baseline covariates. We demonstrate that the Aalen least-squares estimator of the treatment effect parameter is asymptotically unbiased, even when the hazard...... that, in view of its robustness against model misspecification, Aalen least-squares estimation is attractive for evaluating treatment effects on a survival outcome in randomized experiments, and the primary reasons to consider baseline covariate adjustment in such settings could be interest in subgroup...

  20. Dynamic Behavior of Artificial Hodgkin-Huxley Neuron Model Subject to Additive Noise.

    Science.gov (United States)

    Kang, Qi; Huang, BingYao; Zhou, MengChu

    2016-09-01

    Motivated by neuroscience discoveries during the last few years, many studies consider pulse-coupled neural networks with spike-timing as an essential component in information processing by the brain. There also exists some technical challenges while simulating the networks of artificial spiking neurons. The existing studies use a Hodgkin-Huxley (H-H) model to describe spiking dynamics and neuro-computational properties of each neuron. But they fail to address the effect of specific non-Gaussian noise on an artificial H-H neuron system. This paper aims to analyze how an artificial H-H neuron responds to add different types of noise using an electrical current and subunit noise model. The spiking and bursting behavior of this neuron is also investigated through numerical simulations. In addition, through statistic analysis, the intensity of different kinds of noise distributions is discussed to obtain their relationship with the mean firing rate, interspike intervals, and stochastic resonance.

  1. Phase-Field Modeling of Microstructure Evolution in Electron Beam Additive Manufacturing

    Science.gov (United States)

    Gong, Xibing; Chou, Kevin

    2015-05-01

    In this study, the microstructure evolution in the powder-bed electron beam additive manufacturing (EBAM) process is studied using phase-field modeling. In essence, EBAM involves a rapid solidification process and the properties of a build partly depend on the solidification behavior as well as the microstructure of the build material. Thus, the prediction of microstructure evolution in EBAM is of importance for its process optimization. Phase-field modeling was applied to study the microstructure evolution and solute concentration of the Ti-6Al-4V alloy in the EBAM process. The effect of undercooling was investigated through the simulations; the greater the undercooling, the faster the dendrite grows. The microstructure simulations show multiple columnar-grain growths, comparable with experimental results for the tested range.

  2. Evidence for iodine monoxide in the Antarctic snowpack from spectroscopic measurements

    Energy Technology Data Exchange (ETDEWEB)

    Friess, Udo; Deutschmann, Tim; Platt, Ulrich [Institut fuer Umweltphysik, Universitaet Heidelberg (Germany); Gilfedder, Ben [Institut fuer Umweltgeologie, TU-Braunschweig (Germany); Weller, Rolf [Alfred Wegener Institut fuer Polar- und Meeresforschung, Bremerhaven (Germany)

    2010-07-01

    Recent ground-based and space borne observations suggest the presence of significant amounts of iodine monoxide in the boundary layer of Antarctica, which are expected to have an impact on the ozone budget and might contribute to the formation of new airborne particles. So far, the source of these iodine radicals has been unknown. Here we present long-term measurements of iodine monoxide at the German Antarctic research station Neumayer, which indicate that the snowpack is the main source for iodine radicals. The measurements have been performed using multi-axis differential optical absorption spectroscopy (MAX-DOAS). Using a coupled atmosphere - snowpack radiative transfer model, the comparison of the signals observed from scattered skylight and from light reflected by the snowpack yields several ppb of iodine monoxide in the upper layers of the sunlit snowpack throughout the year. Snow pit samples from Neumayer Station contain up to 700 ng/l of total iodine, representing a sufficient reservoir for these extraordinarily high IO concentrations.

  3. [Stable iodine as a prophylaxis therapy following exposure to radioactive iodines: pharmacological and pharmaceutical characteristics].

    Science.gov (United States)

    Hosten, B; Rizzo-Padoin, N; Scherrmann, J-M; Bloch, V

    2012-03-01

    More or less rapid radio-induction of thyroidian cancers is the main pathological consequence of an accidental exposure to ingested or inhaled radioactive iodines following a nuclear power plant accident. The prophylactic administration of potassium iodine in a single oral dose has to be practiced as soon as possible after the nuclear accident. The efficacy of this therapy depends on pharmacokinetics of radioidines. Iodines are rapidly and completely absorbed as iodides. The radioactive iodines, mainly iodine 131, concentrate in the thyroid gland because of a carrier-mediated transport by the Na-I symporter. Administration of stable iodine results in the symporter blockade, which limits the uptake of radioactive iodines by the thyroid and the duration of the internal irradiation. This irradiation will never exceed 3days if the therapy is started between 6h before the accidental exposure and 1h after. The pharmacist asked to dispense the tablets of stable iodine has a important place because, besides his advices on the optimal modalities of taking stable iodine and the risks of unwanted effects, he extend these advices to information on the radioactive risk and on measures of civil and sanitary protection.

  4. Critical evaluation of cadexomer-iodine ointment and povidone-iodine sugar ointment.

    Science.gov (United States)

    Noda, Yasuhiro; Fujii, Kiori; Fujii, Satoshi

    2009-05-01

    Topical iodine forms are used for infected and necrotic pressure ulcers. Despite antimicrobial advantages several potential disadvantages were observed with controversial results. To clarify the controversy, the reactivity of povidone-iodine (PI) sugar ointment and cadexomer-iodine (CI) ointment toward biological components was investigated. L-Tyrosine as a component of proteins and egg lecithin as a component of lipid membranes were reacted with forms of iodine. Furthermore, water absorption abilities of ointments were investigated. The reactions of PI sugar ointment and CI ointment with L-tyrosine were reversely dependent on iodine concentrations. CI ointment reacted with lecithin in an iodine concentration dependent manner, while PI sugar ointment reacted with lecithin in an iodine concentration independent steady manner. However, at the clinically relevant iodine concentration (0.1, w/v%) PI sugar ointment reacted efficiently with L-tyrosine and less efficiently with lecithin, while CI ointment reacted efficiently with lecithin and less efficiently with L-tyrosine. Water absorption rate constant was 29.9 mg/cm(2)/min(0.5) for PI sugar ointment and 15.3 for CI ointment. Water absorption capacity per weight over 24 h was 26% forPI sugar ointment and 76% for CI ointment [corrected]. These results suggest that PI sugar ointment and CI ointment have different characteristics for iodine reactivity and water absorption.

  5. Iodine deficiency in pregnancy in Denmark. Regional variations and frequency of individual iodine supplementation

    DEFF Research Database (Denmark)

    Nøhr, S B; Laurberg, P; Børlum, K G

    1993-01-01

    Iodine requirements are increased during pregnancy and lactation and adequate iodine intake is important for normal brain development of the fetus/newborn child. The aim of the present study was to evaluate the extent to which this increase in iodine requirement is met in pregnant women living...... micrograms/g creatinine). These values are far below internationally recommended levels. The consequences remain to be evaluated and no firm recommendations can be given. It seems reasonable, however, to recommend a high intake of food containing iodine (e.g. milk products) during pregnancy and lactation...

  6. Iodine content in bread, milk and the retention of inherent iodine in commonly used Indian recipes.

    Science.gov (United States)

    Longvah, T; Toteja, G S; Upadhyay, A

    2013-01-15

    Iodine deficiency disorders (IDD) is still a major public health problem and iodized salt remains the most effective means to control IDD in India. Few reports indicate that vegans have inadequate iodine intake while at the same time concerns are being raised on the implementation of universal salt iodization in the country. Therefore, we investigated the iodine content in bread, milk and commonly used Indian recipes prepared without iodized salt and the retention of inherent iodine therein. Results showed considerable iodine content in bread (25 μg/100g) and milk (303 μg/L) as a positive fallout of universal salt iodization. Iodine content in 38 vegetarian recipes prepared without iodized salt was very low (2.9 ± 2.4 μg/100g). Retention of inherent iodine (65.6 ± 15.4%) and iodine from iodized salt (76.7 ± 10.3%) in the same recipes was comparable. Thus, universal salt iodization programme remains the single most important source of dietary iodine for the Indian population. Copyright © 2012 Elsevier Ltd. All rights reserved.

  7. Guarana Provides Additional Stimulation over Caffeine Alone in the Planarian Model

    Science.gov (United States)

    Moustakas, Dimitrios; Mezzio, Michael; Rodriguez, Branden R.; Constable, Mic Andre; Mulligan, Margaret E.; Voura, Evelyn B.

    2015-01-01

    The stimulant effect of energy drinks is primarily attributed to the caffeine they contain. Many energy drinks also contain other ingredients that might enhance the tonic effects of these caffeinated beverages. One of these additives is guarana. Guarana is a climbing plant native to the Amazon whose seeds contain approximately four times the amount of caffeine found in coffee beans. The mix of other natural chemicals contained in guarana seeds is thought to heighten the stimulant effects of guarana over caffeine alone. Yet, despite the growing use of guarana as an additive in energy drinks, and a burgeoning market for it as a nutritional supplement, the science examining guarana and how it affects other dietary ingredients is lacking. To appreciate the stimulant effects of guarana and other natural products, a straightforward model to investigate their physiological properties is needed. The planarian provides such a system. The locomotor activity and convulsive response of planarians with substance exposure has been shown to provide an excellent system to measure the effects of drug stimulation, addiction and withdrawal. To gauge the stimulant effects of guarana we studied how it altered the locomotor activity of the planarian species Dugesia tigrina. We report evidence that guarana seeds provide additional stimulation over caffeine alone, and document the changes to this stimulation in the context of both caffeine and glucose. PMID:25880065

  8. Guarana provides additional stimulation over caffeine alone in the planarian model.

    Directory of Open Access Journals (Sweden)

    Dimitrios Moustakas

    Full Text Available The stimulant effect of energy drinks is primarily attributed to the caffeine they contain. Many energy drinks also contain other ingredients that might enhance the tonic effects of these caffeinated beverages. One of these additives is guarana. Guarana is a climbing plant native to the Amazon whose seeds contain approximately four times the amount of caffeine found in coffee beans. The mix of other natural chemicals contained in guarana seeds is thought to heighten the stimulant effects of guarana over caffeine alone. Yet, despite the growing use of guarana as an additive in energy drinks, and a burgeoning market for it as a nutritional supplement, the science examining guarana and how it affects other dietary ingredients is lacking. To appreciate the stimulant effects of guarana and other natural products, a straightforward model to investigate their physiological properties is needed. The planarian provides such a system. The locomotor activity and convulsive response of planarians with substance exposure has been shown to provide an excellent system to measure the effects of drug stimulation, addiction and withdrawal. To gauge the stimulant effects of guarana we studied how it altered the locomotor activity of the planarian species Dugesia tigrina. We report evidence that guarana seeds provide additional stimulation over caffeine alone, and document the changes to this stimulation in the context of both caffeine and glucose.

  9. Quantifying spatial disparities in neonatal mortality using a structured additive regression model.

    Directory of Open Access Journals (Sweden)

    Lawrence N Kazembe

    Full Text Available BACKGROUND: Neonatal mortality contributes a large proportion towards early childhood mortality in developing countries, with considerable geographical variation at small areas within countries. METHODS: A geo-additive logistic regression model is proposed for quantifying small-scale geographical variation in neonatal mortality, and to estimate risk factors of neonatal mortality. Random effects are introduced to capture spatial correlation and heterogeneity. The spatial correlation can be modelled using the Markov random fields (MRF when data is aggregated, while the two dimensional P-splines apply when exact locations are available, whereas the unstructured spatial effects are assigned an independent Gaussian prior. Socio-economic and bio-demographic factors which may affect the risk of neonatal mortality are simultaneously estimated as fixed effects and as nonlinear effects for continuous covariates. The smooth effects of continuous covariates are modelled by second-order random walk priors. Modelling and inference use the empirical Bayesian approach via penalized likelihood technique. The methodology is applied to analyse the likelihood of neonatal deaths, using data from the 2000 Malawi demographic and health survey. The spatial effects are quantified through MRF and two dimensional P-splines priors. RESULTS: Findings indicate that both fixed and spatial effects are associated with neonatal mortality. CONCLUSIONS: Our study, therefore, suggests that the challenge to reduce neonatal mortality goes beyond addressing individual factors, but also require to understanding unmeasured covariates for potential effective interventions.

  10. Nonparametric Independence Screening in Sparse Ultra-High Dimensional Additive Models.

    Science.gov (United States)

    Fan, Jianqing; Feng, Yang; Song, Rui

    2011-06-01

    A variable screening procedure via correlation learning was proposed in Fan and Lv (2008) to reduce dimensionality in sparse ultra-high dimensional models. Even when the true model is linear, the marginal regression can be highly nonlinear. To address this issue, we further extend the correlation learning to marginal nonparametric learning. Our nonparametric independence screening is called NIS, a specific member of the sure independence screening. Several closely related variable screening procedures are proposed. Under general nonparametric models, it is shown that under some mild technical conditions, the proposed independence screening methods enjoy a sure screening property. The extent to which the dimensionality can be reduced by independence screening is also explicitly quantified. As a methodological extension, a data-driven thresholding and an iterative nonparametric independence screening (INIS) are also proposed to enhance the finite sample performance for fitting sparse additive models. The simulation results and a real data analysis demonstrate that the proposed procedure works well with moderate sample size and large dimension and performs better than competing methods.

  11. Combining neuroprotectants in a model of retinal degeneration: no additive benefit.

    Directory of Open Access Journals (Sweden)

    Fabiana Di Marco

    Full Text Available The central nervous system undergoing degeneration can be stabilized, and in some models can be restored to function, by neuroprotective treatments. Photobiomodulation (PBM and dietary saffron are distinctive as neuroprotectants in that they upregulate protective mechanisms, without causing measurable tissue damage. This study reports a first attempt to combine the actions of PBM and saffron. Our working hypothesis was that the actions of PBM and saffron in protecting retinal photoreceptors, in a rat light damage model, would be additive. Results confirmed the neuroprotective potential of each used separately, but gave no evidence that their effects are additive. Detailed analysis suggests that there is actually a negative interaction between PBM and saffron when given simultaneously, with a consequent reduction of the neuroprotection. Specific testing will be required to understand the mechanisms involved and to establish whether there is clinical potential in combining neuroprotectants, to improve the quality of life of people affected by retinal pathology, such as age-related macular degeneration, the major cause of blindness and visual impairment in older adults.

  12. Modeling protein density of states: additive hydrophobic effects are insufficient for calorimetric two-state cooperativity.

    Science.gov (United States)

    Chan, H S

    2000-09-01

    A well-established experimental criterion for two-state thermodynamic cooperativity in protein folding is that the van't Hoff enthalpy DeltaH(vH) around the transition midpoint is equal, or very nearly so, to the calorimetric enthalpy DeltaH(cal) of the entire transition. This condition is satisfied by many small proteins. We use simple lattice models to provide a statistical mechanical framework to elucidate how this calorimetric two-state picture may be reconciled with the hierarchical multistate scenario emerging from recent hydrogen exchange experiments. We investigate the feasibility of using inverse Laplace transforms to recover the underlying density of states (i.e., enthalpy distribution) from calorimetric data. We find that the constraint imposed by DeltaH(vH)/DeltaH(cal) approximately 1 on densities of states of proteins is often more stringent than other "two-state" criteria proposed in recent theoretical studies. In conjunction with reasonable assumptions, the calorimetric two-state condition implies a narrow distribution of denatured-state enthalpies relative to the overall enthalpy difference between the native and the denatured conformations. This requirement does not always correlate with simple definitions of "sharpness" of a transition and has important ramifications for theoretical modeling. We find that protein models that assume capillarity cooperativity can exhibit overall calorimetric two-state-like behaviors. However, common heteropolymer models based on additive hydrophobic-like interactions, including highly specific two-dimensional Gō models, fail to produce proteinlike DeltaH(vH)/DeltaH(cal) approximately 1. A simple model is constructed to illustrate a proposed scenario in which physically plausible local and nonlocal cooperative terms, which mimic helical cooperativity and environment-dependent hydrogen bonding strength, can lead to thermodynamic behaviors closer to experiment. Our results suggest that proteinlike thermodynamic

  13. Modeling and Fault Monitoring of Bioprocess Using Generalized Additive Models (GAMs) and Bootstrap%Modeling and Fault Monitoring of Bioprocess Using Generalized Additive Models (GAMs) and Bootstrap

    Institute of Scientific and Technical Information of China (English)

    郑蓉建; 周林成; 潘丰

    2012-01-01

    Fault monitoring of bioprocess is important to ensure safety of a reactor and maintain high quality of products. It is difficult to build an accurate mechanistic model for a bioprocess, so fault monitoring based on rich historical or online database is an effective way. A group of data based on bootstrap method could be resampling stochastically, improving generalization capability of model. In this paper, online fault monitoring of generalized additive models (GAMs) combining with bootstrap is proposed for glutamate fermentation process. GAMs and bootstrap are first used to decide confidence interval based on the online and off-line normal sampled data from glutamate fermentation experiments. Then GAMs are used to online fault monitoring for time, dissolved oxygen, oxygen uptake rate, and carbon dioxide evolution rate. The method can provide accurate fault alarm online and is helpful to provide useful information for removing fault and abnormal phenomena in the fermentation.

  14. Predicting infectivity of Arbuscular Mycorrhizal fungi from soil variables using Generalized Additive Models and Generalized Linear Models

    Directory of Open Access Journals (Sweden)

    IRNANDA AIKO FIFI DJUUNA

    2010-07-01

    Full Text Available Djuuna IAF, Abbott LK, Van Niel K (2010 Predicting infectivity of Arbuscular Mycorrhizal fungi from soil variables using Generalized Additive Models and Generalized Linear Models. Biodiversitas 11: 145-150. The objective of this study was to predict the infectivity of arbuscular mycorrhizal fungi (AM fungi, from field soil based on soil properties and land use history using generalized additive models (GAMs and generalized linear models (GLMs. A total of 291 soil samples from a farm in Western Australia near Wickepin were collected and used in this study. Nine soil properties, including elevation, pH, EC, total C, total N, P, K, microbial biomass carbon, and soil texture, and land use history of the farm were used as independent variables, while the percentage of root length colonized (%RLC was used as the dependent variable. GAMs parameterized for the percent of root length colonized suggested skewed quadratic responses to soil pH and microbial biomass carbon; cubic responses to elevation and soil K; and linear responses to soil P, EC and total C. The strength of the relationship between percent root length colonized by AM fungi and environmental variables showed that only elevation, total C and microbial biomass carbon had strong relationships. In general, GAMs and GLMs models confirmed the strong relationship between infectivity of AM fungi (assessed in a glasshouse bioassay for soil collected in summer prior to the first rain of the season and soil properties.

  15. Quasi-additive estimates on the Hamiltonian for the one-dimensional long range Ising model

    Science.gov (United States)

    Littin, Jorge; Picco, Pierre

    2017-07-01

    In this work, we study the problem of getting quasi-additive bounds for the Hamiltonian of the long range Ising model, when the two-body interaction term decays proportionally to 1/d2 -α , α ∈(0,1 ) . We revisit the paper by Cassandro et al. [J. Math. Phys. 46, 053305 (2005)] where they extend to the case α ∈[0 ,ln3/ln2 -1 ) the result of the existence of a phase transition by using a Peierls argument given by Fröhlich and Spencer [Commun. Math. Phys. 84, 87-101 (1982)] for α =0 . The main arguments of Cassandro et al. [J. Math. Phys. 46, 053305 (2005)] are based in a quasi-additive decomposition of the Hamiltonian in terms of hierarchical structures called triangles and contours, which are related to the original definition of contours introduced by Fröhlich and Spencer [Commun. Math. Phys. 84, 87-101 (1982)]. In this work, we study the existence of a quasi-additive decomposition of the Hamiltonian in terms of the contours defined in the work of Cassandro et al. [J. Math. Phys. 46, 053305 (2005)]. The most relevant result obtained is Theorem 4.3 where we show that there is a quasi-additive decomposition for the Hamiltonian in terms of contours when α ∈[0,1 ) but not in terms of triangles. The fact that it cannot be a quasi-additive bound in terms of triangles lead to a very interesting maximization problem whose maximizer is related to a discrete Cantor set. As a consequence of the quasi-additive bounds, we prove that we can generalise the [Cassandro et al., J. Math. Phys. 46, 053305 (2005)] result, that is, a Peierls argument, to the whole interval α ∈[0,1 ) . We also state here the result of Cassandro et al. [Commun. Math. Phys. 327, 951-991 (2014)] about cluster expansions which implies that Theorem 2.4 that concerns interfaces and Theorem 2.5 that concerns n point truncated correlation functions in Cassandro et al. [Commun. Math. Phys. 327, 951-991 (2014)] are valid for all α ∈[0,1 ) instead of only α ∈[0 ,ln3/ln2 -1 ) .

  16. PREVALENCE AND SEVERITY OF IODINE DEFICIENCY ...

    African Journals Online (AJOL)

    GB

    2012-11-03

    Nov 3, 2012 ... that severe iodine deficiency in Ethiopian women leads to 50,000 ... there will be hypothyroidism that causes low metabolic ... high in pregnant mothers and in school children as evidenced by research articles. Especially in.

  17. PREVALENCE AND SEVERITY OF IODINE DEFICIENCY ...

    African Journals Online (AJOL)

    GB

    2012-11-03

    Nov 3, 2012 ... BACKGROUND: Iodine deficiency disorder is a major problem worldwide, .... method involves the titration of a solution of salt ..... blocks the thyroid peroxidase enzyme (29, 34). .... Modern Nutrition in Health and Disease, Lea.

  18. Iodine Hall Thruster for Space Exploration Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Busek Co. Inc. proposes to develop a high power (high thrust) electric propulsion system featuring an iodine fueled Hall Effect Thruster (HET). The system to be...

  19. Fundamentals of Thyroid Hormone Physiology, Iodine Metabolism ...

    African Journals Online (AJOL)

    of iodine and thyroid stimulating hormone (thyrotropin, TSH). To produce T4 at ... for adequate T4 release, a number of factors can modify this ..... Lipid M etabolism. R educed appetite; impaired protein metabolism; reduced glucose deposition.

  20. [Nutritive correction and iodine deficiency in children].

    Science.gov (United States)

    Shilina, N M; Pozdniakov, A L

    2007-01-01

    It is well known that deficiency of calcium and iodine--essential food components needed for children's valuable growth and development--is observed presently in children of different age. Considering this fact, the "Danone" company together with Institute of Nutrition (Russia) has developed a special formula, including calcium, iodine and vitamin D, for dairy products "Rastishka". The use of these products facilitates both reducing the risk of the above mentioned microelement deficiency and children's growth and development.

  1. Environmental controls on iodine deficiency disorders (IDD)

    OpenAIRE

    Johnson, C C; Fordyce, F.M.

    2003-01-01

    It is estimated that in excess of one billion people world-wide are at risk from iodine deficiency disorders (IDD), the most obvious manifestation of which is goitre (see Fordyce, 2000). Iodine deficiency is the world’s most common cause of mental retardation and brain damage, and the negative effects of impaired mental function have a significant impact on the social and economic development of communities. Although IDD can be caused by a number of factors, goitrogens fo...

  2. Impact of an additional chronic BDNF reduction on learning performance in an Alzheimer mouse model

    Directory of Open Access Journals (Sweden)

    Laura ePsotta

    2015-03-01

    Full Text Available There is increasing evidence that brain-derived neurotrophic factor (BDNF plays a crucial role in AD pathology. A number of studies demonstrated that AD patients exhibit reduced BDNF levels in the brain and the blood serum, and in addition, several animal-based studies indicated a potential protective effect of BDNF against Aβ-induced neurotoxicity. In order to further investigate the role of BDNF in the etiology of AD, we created a novel mouse model by crossing a well-established AD mouse model (APP/PS1 with a mouse exhibiting a chronic BDNF deficiency (BDNF+/-. This new triple transgenic mouse model enabled us to further analyze the role of BDNF in AD in vivo. We reasoned that in case BDNF has a protective effect against AD pathology, an AD-like phenotype in our new mouse model should occur earlier and/or in more severity than in the APP/PS1-mice. Indeed, the behavioral analysis re-vealed that the APP/PS1-BDNF+/--mice show an earlier onset of learning impairments in a two-way active avoidance task in comparison to APP/PS1- and BDNF+/--mice. However in the Morris water maze test, we could not observe an overall aggrevated impairment in spatial learning and also short-term memory in an object recognition task remained intact in all tested mouse lines. In addition to the behavioral experiments, we analyzed the amyloid plaque pa-thology in the APP/PS1 and APP/PS1-BDNF+/--mice and observed a comparable plaque den-sity in the two genotypes. Moreover, our results revealed a higher plaque density in prefrontal cortical compared to hippocampal brain regions. Our data reveal that higher cognitive tasks requiring the recruitment of cortical networks appear to be more severely affected in our new mouse model than learning tasks requiring mainly sub-cortical networks. Furthermore, our observations of an accelerated impairment in active avoidance learning in APP/PS1-BDNF+/--mice further supports the hypothesis that BDNF deficiency amplifies AD

  3. Nonlinear feedback in a six-dimensional Lorenz Model: impact of an additional heating term

    Directory of Open Access Journals (Sweden)

    B.-W. Shen

    2015-03-01

    Full Text Available In this study, a six-dimensional Lorenz model (6DLM is derived, based on a recent study using a five-dimensional (5-D Lorenz model (LM, in order to examine the impact of an additional mode and its accompanying heating term on solution stability. The new mode added to improve the representation of the steamfunction is referred to as a secondary streamfunction mode, while the two additional modes, that appear in both the 6DLM and 5DLM but not in the original LM, are referred to as secondary temperature modes. Two energy conservation relationships of the 6DLM are first derived in the dissipationless limit. The impact of three additional modes on solution stability is examined by comparing numerical solutions and ensemble Lyapunov exponents of the 6DLM and 5DLM as well as the original LM. For the onset of chaos, the critical value of the normalized Rayleigh number (rc is determined to be 41.1. The critical value is larger than that in the 3DLM (rc ~ 24.74, but slightly smaller than the one in the 5DLM (rc ~ 42.9. A stability analysis and numerical experiments obtained using generalized LMs, with or without simplifications, suggest the following: (1 negative nonlinear feedback in association with the secondary temperature modes, as first identified using the 5DLM, plays a dominant role in providing feedback for improving the solution's stability of the 6DLM, (2 the additional heating term in association with the secondary streamfunction mode may destabilize the solution, and (3 overall feedback due to the secondary streamfunction mode is much smaller than the feedback due to the secondary temperature modes; therefore, the critical Rayleigh number of the 6DLM is comparable to that of the 5DLM. The 5DLM and 6DLM collectively suggest different roles for small-scale processes (i.e., stabilization vs. destabilization, consistent with the following statement by Lorenz (1972: If the flap of a butterfly's wings can be instrumental in generating a tornado, it

  4. Modeling additional solar constraints on a human being inside a room

    Energy Technology Data Exchange (ETDEWEB)

    Thellier, Francoise; Monchoux, Francoise; Bonnis-Sassi, Michel; Lartigue, Berengere [Laboratoire Physique de l' Homme Appliquee a Son Environnement (PHASE), Universite Paul Sabatier, 118, route de Narbonne, F-31062 Toulouse Cedex 9 (France)

    2008-04-15

    Sun fluxes induce additional heterogeneous thermal constraints in buildings and may also lead to discomfort for the inhabitant. To calculate the local thermal sensation of a human being totally or partially situated in the sunlight, the solar radiation inside a room and its detailed distribution on parts of the human body are modeled. The present study focuses on the solar gains part of a complete modeling tool simulating an occupied building. The irradiated areas are calculated with a ray tracing method taking shadow into account. Solar fluxes are computed. Fluxes can be absorbed by each surface or reflected. The reflected fluxes are then absorbed at the next impact. A multi-node thermoregulation model (MARCL) represents the thermal behavior of the human body and all its heat exchanges with the environment. The thermal transient simulation of the whole occupied building is performed in TRNSYS simulation software. In the case presented here, the results show that, when a person is inside the building, the skin and clothing temperatures of the irradiated segments increase more or less depending on the segments but the global thermal equilibrium of the body is maintained thanks to strong physiological reactions. (author)

  5. A Bayesian additive model for understanding public transport usage in special events.

    Science.gov (United States)

    Rodrigues, Filipe; Borysov, Stanislav; Ribeiro, Bernardete; Pereira, Francisco

    2016-12-02

    Public special events, like sports games, concerts and festivals are well known to create disruptions in transportation systems, often catching the operators by surprise. Although these are usually planned well in advance, their impact is difficult to predict, even when organisers and transportation operators coordinate. The problem highly increases when several events happen concurrently. To solve these problems, costly processes, heavily reliant on manual search and personal experience, are usual practice in large cities like Singapore, London or Tokyo. This paper presents a Bayesian additive model with Gaussian process components that combines smart card records from public transport with context information about events that is continuously mined from the Web. We develop an efficient approximate inference algorithm using expectation propagation, which allows us to predict the total number of public transportation trips to the special event areas, thereby contributing to a more adaptive transportation system. Furthermore, for multiple concurrent event scenarios, the proposed algorithm is able to disaggregate gross trip counts into their most likely components related to specific events and routine behavior. Using real data from Singapore, we show that the presented model outperforms the best baseline model by up to 26% in R2 and also has explanatory power for its individual components.

  6. The Success Rate of Initial {sup 131I} Ablation in Differentiated Thyroid Cancer: Comparison Between Less strict and Very Strict Low Iodine Diets

    Energy Technology Data Exchange (ETDEWEB)

    Yoo, Ik Dong; Kim, Sung Hoon; Seo, Ye Young; Oh, Jin Kyoung; O, Joo Hyun; Chung, Soo Kyo [The Catholic Univ. of Korea, Seoul (Korea, Republic of)

    2012-03-15

    To decrease the risk of recurrence or metastasis in differentiated thyroid cancer (DTC), selected patients receive radioactive iodine ablation of remnant thyroid tissue or tumor. A low iodine diet can enhance uptake of radioactive iodine. We compared the success rates of radioactive iodine ablation therapy in patients who followed two different low iodine diets (LIDs). The success rates of postsurgical radioactive iodine ablation in DTC patients receiving empiric doses of 150 mCi were retrospectively reviewed. First-time radioactive iodine ablation therapy was done in 71 patients following less strict LID. Less strict LID restricted seafood, iodized salt, egg yolk, dairy products, processed meat, instant prepared meals, and multivitamins. Very strict LID additionally restricted rice, freshwater fish, spinach, and soybean products. Radioactive iodine ablation therapy was considered successful when follow up {sup 123I} whole body scan was negative and stimulated serum thyroglobulin level was less than 2.0 ng/mL. The success rate of patients following less strict LID was 80.3% and for very strict LID 75.6%. There was no statistically significant difference in the success rates between the two LID groups (P=0.48). Very strict LID may not contribute to improving the success rate of initial radioactive iodine ablation therapy at the cost of great inconvenience to the patient.

  7. Iodine-125 interstitial brachytherapy for experimental liver cancer

    Institute of Scientific and Technical Information of China (English)

    ZHOU Fei-guo; YAN Jian-jun; HUANG Liang; LIU Cai-feng; ZHANG Xiang-hua; ZHOU Wei-ping; YAN Yi-qun

    2007-01-01

    Objective:To study the effect of iodine-125 interstitial brachytherapy on liver cancer.Methods:Animal model of human liver cancer was established by injecting SMMC-7721 cells cultivated in vitro subcutaneously into the flank of BALB/c nude mice.Nude mice with tumor of 5 mm in diameter were randomly divided into 2 groups(n=10).One iodine-125 seed of apparent activity 0.8 mCi was implanted into the center of tumor in treatment group,whereas an inactive seed was implanted in control group.The other 20 nude mice with tumor reaching 10 mm in diameter were also treated as above.The size of tumor was determined weekly after implantation,and pathological examination and blood routine were taken on the 28th day.Results:Tumor growth was obviously inhibited in treatment group of tumor of 5 mm in diameter,and there was statistically significant difference in tumor volume between treatment and control groups(P<0.01).Around iodine-125 seed,apparent necrosis of tumor was shown in treatment group,accompanied by karyopyknosis and reduced plasma in residual tumor cells microscopically.Tumor growth was not inhibited in either treatment or control group of tumor of 10 mm in diameter.There was no obvious adverse effect except for decreased white blood cells in treatment groups.Conclusion:There is certain effect of iodine-125 interstitial brachytherapy on liver cancer,which is associated with the size of tumor.

  8. Thyroid and iodine nutritional status: a UK perspective.

    Science.gov (United States)

    Vanderpump, Mark

    2014-12-01

    Iodine is an essential component of the thyroid hormones, which play a crucial role in brain and neurological development. At least one-third of the world's population is estimated to be iodine deficient predominantly in developing countries. Recently concern had also been expressed about the iodine status in industrialised countries such as the UK. A recent survey of the UK iodine status found that that more than two-thirds of schoolgirls aged 14-15 years were iodine deficient due to the reduced milk intake. Maternal iodine deficiency in pregnancy is correlated with cognitive outcomes such as intelligence quotient and reading ability in offspring. No randomised trial data exist for iodine supplementation in mild-moderate iodine-deficient pregnant women. It is possible to combine population interventions to reduce population salt intake with salt iodisation programmes in order to maintain adequate levels of iodine nutrition.

  9. New iodine derivatives of flavonol and isoflavone

    Directory of Open Access Journals (Sweden)

    Mário G. de Carvalho

    2009-03-01

    Full Text Available The reaction of the flavonol 3,7,3', 4'-tetra-O-methylquercetin (1 and of the isoflavone 7,4'-di-O-methylgenistein (2 with alkaline iodine in methanol afforded four new iodine derivatives: 8-iodo-5-hydroxy-3,7,3', 4'-tetramethoxy- flavone (1a and 6-iodo-5-hydroxy-3,7,3', 4'-tetramethoxyflavone (1b from 1; 2 afforded a mixture of two compounds, identified as a racemic mixture of (±-trans-5-hydroxy-2,3,7,4'-tetramethoxy-8-iodo-isoflavanone (2a and (±-trans-5-hydroxy-2,3,7,4'-tetramethoxy-6,8-diiodo-isoflavanone (2b. The formation of these different products reveals a significant difference involving the chemical interaction between the reactive site of α, β-unsaturated ketones of flavonol and isoflavone under the tested reaction conditions (using I2/KOH/MeOH. Furthermore, the trans stereo selectivity is noteworthy in the nucleophylic addition of methanol at the isoflavone α, β-unsaturated system. The structures were identified on the basis of spectral data, mainly 1D and 2D NMR and mass spectra.A reação do flavonol 3,7,3',4'-tetra-O-metilquercetina (1 e da isoflavona 7,4'-di-O-metilgenisteina (2 com iodo/KOH em metanol forneceu como produto quatro derivados iodados: 8-iodo-5-hidroxi-3,7,3',4'-tetrametoxiflavona (1a e 6-iodo-5-hidroxi-3,7,3',4'-tetrametoxiflavona (1b a partir da iodação de 1; a partir de 2 foi obtida uma mistura racêmica composta de (±-trans-5-hidroxi-2,3,7,4'-tetrametoxi-8-iodo-isoflavanona (2a e (±-trans-5-hidroxi-2,3,7,4'-tetrametoxi-6,8-diiodo-isoflavanona (2b. A formação destes diferentes produtos revela a significante diferença envolvendo a interação química entre o sitio reativo de cetonas α, β-insaturadas de flavonol e de isoflavonas nas condições experimentais testadas (usando I2/KOH/MeOH. Além disso, ressalta-se a estereosseletividade trans na adição de metanol ao sistema α, β-insaturado da isoflavona. As estruturas foram identificadas com análise nos dados espectrométricos de RMN 1D e 2D e

  10. A Modified Weighted Symmetric Estimator for a Gaussian First-order Autoregressive Model with Additive Outliers

    Directory of Open Access Journals (Sweden)

    Wararit PANICHKITKOSOLKUL

    2012-09-01

    Full Text Available Guttman and Tiao [1], and Chang [2] showed that the effect of outliers may cause serious bias in estimating autocorrelations, partial correlations, and autoregressive moving average parameters (cited in Chang et al. [3]. This paper presents a modified weighted symmetric estimator for a Gaussian first-order autoregressive AR(1 model with additive outliers. We apply the recursive median adjustment based on an exponentially weighted moving average (EWMA to the weighted symmetric estimator of Park and Fuller [4]. We consider the following estimators: the weighted symmetric estimator (, the recursive mean adjusted weighted symmetric estimator ( proposed by Niwitpong [5], the recursive median adjusted weighted symmetric estimator ( proposed by Panichkitkosolkul [6], and the weighted symmetric estimator using adjusted recursive median based on EWMA (. Using Monte Carlo simulations, we compare the mean square error (MSE of estimators. Simulation results have shown that the proposed estimator, , provides a MSE lower than those of , and  for almost all situations.

  11. Design and tuning of standard additive model based fuzzy PID controllers for multivariable process systems.

    Science.gov (United States)

    Harinath, Eranda; Mann, George K I

    2008-06-01

    This paper describes a design and two-level tuning method for fuzzy proportional-integral derivative (FPID) controllers for a multivariable process where the fuzzy inference uses the inference of standard additive model. The proposed method can be used for any n x n multi-input-multi-output process and guarantees closed-loop stability. In the two-level tuning scheme, the tuning follows two steps: low-level tuning followed by high-level tuning. The low-level tuning adjusts apparent linear gains, whereas the high-level tuning changes the nonlinearity in the normalized fuzzy output. In this paper, two types of FPID configurations are considered, and their performances are evaluated by using a real-time multizone temperature control problem having a 3 x 3 process system.

  12. Modeling the flux of metabolites in the juvenile hormone biosynthesis pathway using generalized additive models and ordinary differential equations.

    Science.gov (United States)

    Martínez-Rincón, Raúl O; Rivera-Pérez, Crisalejandra; Diambra, Luis; Noriega, Fernando G

    2017-01-01

    Juvenile hormone (JH) regulates development and reproductive maturation in insects. The corpora allata (CA) from female adult mosquitoes synthesize fluctuating levels of JH, which have been linked to the ovarian development and are influenced by nutritional signals. The rate of JH biosynthesis is controlled by the rate of flux of isoprenoids in the pathway, which is the outcome of a complex interplay of changes in precursor pools and enzyme levels. A comprehensive study of the changes in enzymatic activities and precursor pool sizes have been previously reported for the mosquito Aedes aegypti JH biosynthesis pathway. In the present studies, we used two different quantitative approaches to describe and predict how changes in the individual metabolic reactions in the pathway affect JH synthesis. First, we constructed generalized additive models (GAMs) that described the association between changes in specific metabolite concentrations with changes in enzymatic activities and substrate concentrations. Changes in substrate concentrations explained 50% or more of the model deviances in 7 of the 13 metabolic steps analyzed. Addition of information on enzymatic activities almost always improved the fitness of GAMs built solely based on substrate concentrations. GAMs were validated using experimental data that were not included when the model was built. In addition, a system of ordinary differential equations (ODE) was developed to describe the instantaneous changes in metabolites as a function of the levels of enzymatic catalytic activities. The results demonstrated the ability of the models to predict changes in the flux of metabolites in the JH pathway, and can be used in the future to design and validate experimental manipulations of JH synthesis.

  13. Modeling the flux of metabolites in the juvenile hormone biosynthesis pathway using generalized additive models and ordinary differential equations

    Science.gov (United States)

    Martínez-Rincón, Raúl O.; Rivera-Pérez, Crisalejandra; Diambra, Luis; Noriega, Fernando G.

    2017-01-01

    Juvenile hormone (JH) regulates development and reproductive maturation in insects. The corpora allata (CA) from female adult mosquitoes synthesize fluctuating levels of JH, which have been linked to the ovarian development and are influenced by nutritional signals. The rate of JH biosynthesis is controlled by the rate of flux of isoprenoids in the pathway, which is the outcome of a complex interplay of changes in precursor pools and enzyme levels. A comprehensive study of the changes in enzymatic activities and precursor pool sizes have been previously reported for the mosquito Aedes aegypti JH biosynthesis pathway. In the present studies, we used two different quantitative approaches to describe and predict how changes in the individual metabolic reactions in the pathway affect JH synthesis. First, we constructed generalized additive models (GAMs) that described the association between changes in specific metabolite concentrations with changes in enzymatic activities and substrate concentrations. Changes in substrate concentrations explained 50% or more of the model deviances in 7 of the 13 metabolic steps analyzed. Addition of information on enzymatic activities almost always improved the fitness of GAMs built solely based on substrate concentrations. GAMs were validated using experimental data that were not included when the model was built. In addition, a system of ordinary differential equations (ODE) was developed to describe the instantaneous changes in metabolites as a function of the levels of enzymatic catalytic activities. The results demonstrated the ability of the models to predict changes in the flux of metabolites in the JH pathway, and can be used in the future to design and validate experimental manipulations of JH synthesis. PMID:28158248

  14. Aggregation of gluten proteins in model dough after fibre polysaccharide addition.

    Science.gov (United States)

    Nawrocka, Agnieszka; Szymańska-Chargot, Monika; Miś, Antoni; Wilczewska, Agnieszka Z; Markiewicz, Karolina H

    2017-09-15

    FT-Raman spectroscopy, thermogravimetry and differential scanning calorimetry were used to study changes in structure of gluten proteins and their thermal properties influenced by four dietary fibre polysaccharides (microcrystalline cellulose, inulin, apple pectin and citrus pectin) during development of a model dough. The flour reconstituted from wheat starch and wheat gluten was mixed with the polysaccharides in five concentrations: 3%, 6%, 9%, 12% and 18%. The obtained results showed that all polysaccharides induced similar changes in secondary structure of gluten proteins concerning formation of aggregates (1604cm(-1)), H-bonded parallel- and antiparallel-β-sheets (1690cm(-1)) and H-bonded β-turns (1664cm(-1)). These changes concerned mainly glutenins since β-structures are characteristic for them. The observed structural changes confirmed hypothesis about partial dehydration of gluten network after polysaccharides addition. The gluten aggregation and dehydration processes were also reflected in the DSC results, while the TGA ones showed that gluten network remained thermally stable after polysaccharides addition. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. Impact of biochar addition on thermal properties of a sandy soil: modelling approach

    Science.gov (United States)

    Usowicz, Boguslaw; Lipiec, Jerzy; Lukowski, Mateusz; Bis, Zbigniew; Marczewski, Wojciech; Usowicz, Jerzy

    2017-04-01

    Adding biochar can alter soil thermal properties and increase the water holding capacity and reduce the mineral soil fertilization. Biochar in the soil can determine the heat balance on the soil surface and the temperature distribution in the soil profile through changes in albedo and the thermal properties. Besides, amendment of soil with biochar results in improvement of water retention, fertility and pH that are of importance in sandy and acid soils, widely used in agriculture. In this study we evaluated the effects of wood-derived biochar (0, 10, 20, and 40 Mg ha-1) incorporated to a depth of 0-15 cm on the thermal conductivity, heat capacity, thermal diffusivity and porosity in sandy soil under field conditions. In addition, soil-biochar mixtures of various percentages of biochar were prepared to determine the thermal properties in function of soil water status and density in laboratory. It was shown that a small quantity of biochar added to the soil does not significantly affect all the thermal properties of the soil. Increasing biochar concentration significantly enhanced porosity and decreased thermal conductivity and diffusivity with different rate depending on soil water status. The soil thermal conductivity and diffusivity varied widely and non-linearly with water content for different biochar content and soil bulk density. However, the heat capacity increased with biochar addition and water content linearly and was greater at higher than lower soil water contents. The measured and literature thermal data were compared with those obtained from the analytic model of Zhang et al. (2013) and statistical-physical model (Usowicz et al., 2016) based on soil texture, biochar content, bulk density and water content.

  16. The impact of iodised salt or iodine supplements on iodine status during pregnancy lactation and infancy

    NARCIS (Netherlands)

    Zimmermann, M.B.

    2007-01-01

    Objectives: Monitoring of iodine status during pregnancy, lactation and infancy is difficult as there are no established reference criteria for urinary iodine concentration (UI) for these groups; so it is uncertain whether iodized salt programs meet the needs of these life stages. Design and Subject

  17. Additive surface complexation modeling of uranium(VI) adsorption onto quartz-sand dominated sediments.

    Science.gov (United States)

    Dong, Wenming; Wan, Jiamin

    2014-06-17

    Many aquifers contaminated by U(VI)-containing acidic plumes are composed predominantly of quartz-sand sediments. The F-Area of the Savannah River Site (SRS) in South Carolina (USA) is an example. To predict U(VI) mobility and natural attenuation, we conducted U(VI) adsorption experiments using the F-Area plume sediments and reference quartz, goethite, and kaolinite. The sediments are composed of ∼96% quartz-sand and 3-4% fine fractions of kaolinite and goethite. We developed a new humic acid adsorption method for determining the relative surface area abundances of goethite and kaolinite in the fine fractions. This method is expected to be applicable to many other binary mineral pairs, and allows successful application of the component additivity (CA) approach based surface complexation modeling (SCM) at the SRS F-Area and other similar aquifers. Our experimental results indicate that quartz has stronger U(VI) adsorption ability per unit surface area than goethite and kaolinite at pH ≤ 4.0. Our modeling results indicate that the binary (goethite/kaolinite) CA-SCM under-predicts U(VI) adsorption to the quartz-sand dominated sediments at pH ≤ 4.0. The new ternary (quartz/goethite/kaolinite) CA-SCM provides excellent predictions. The contributions of quartz-sand, kaolinite, and goethite to U(VI) adsorption and the potential influences of dissolved Al, Si, and Fe are also discussed.

  18. Modelling of C2 addition route to the formation of C60

    CERN Document Server

    Khan, Sabih D

    2016-01-01

    To understand the phenomenon of fullerene growth during its synthesis, an attempt is made to model a minimum energy growth route using a semi-empirical quantum mechanics code. C2 addition leading to C60 was modelled and three main routes, i.e. cyclic ring growth, pentagon and fullerene road, were studied. The growth starts with linear chains and, at n = 10, ring structures begins to dominate. The rings continue to grow and, at some point n > 30, they transform into close-cage fullerenes and the growth is shown to progress by the fullerene road until C60 is formed. The computer simulations predict a transition from a C38 ring to fullerene. Other growth mechanisms could also occur in the energetic environment commonly encountered in fullerene synthesis, but our purpose was to identify a minimal energy route which is the most probable structure. Our results also indicate that, at n = 20, the corannulene structure is energetically more stable than the corresponding fullerene and graphene sheet, however a ring str...

  19. Modeling and additive manufacturing of bio-inspired composites with tunable fracture mechanical properties.

    Science.gov (United States)

    Dimas, Leon S; Buehler, Markus J

    2014-07-07

    Flaws, imperfections and cracks are ubiquitous in material systems and are commonly the catalysts of catastrophic material failure. As stresses and strains tend to concentrate around cracks and imperfections, structures tend to fail far before large regions of material have ever been subjected to significant loading. Therefore, a major challenge in material design is to engineer systems that perform on par with pristine structures despite the presence of imperfections. In this work we integrate knowledge of biological systems with computational modeling and state of the art additive manufacturing to synthesize advanced composites with tunable fracture mechanical properties. Supported by extensive mesoscale computer simulations, we demonstrate the design and manufacturing of composites that exhibit deformation mechanisms characteristic of pristine systems, featuring flaw-tolerant properties. We analyze the results by directly comparing strain fields for the synthesized composites, obtained through digital image correlation (DIC), and the computationally tested composites. Moreover, we plot Ashby diagrams for the range of simulated and experimental composites. Our findings show good agreement between simulation and experiment, confirming that the proposed mechanisms have a significant potential for vastly improving the fracture response of composite materials. We elucidate the role of stiffness ratio variations of composite constituents as an important feature in determining the composite properties. Moreover, our work validates the predictive ability of our models, presenting them as useful tools for guiding further material design. This work enables the tailored design and manufacturing of composites assembled from inferior building blocks, that obtain optimal combinations of stiffness and toughness.

  20. Generalized additive models reveal the intrinsic complexity of wood formation dynamics.

    Science.gov (United States)

    Cuny, Henri E; Rathgeber, Cyrille B K; Kiessé, Tristan Senga; Hartmann, Felix P; Barbeito, Ignacio; Fournier, Meriem

    2013-04-01

    The intra-annual dynamics of wood formation, which involves the passage of newly produced cells through three successive differentiation phases (division, enlargement, and wall thickening) to reach the final functional mature state, has traditionally been described in conifers as three delayed bell-shaped curves followed by an S-shaped curve. Here the classical view represented by the 'Gompertz function (GF) approach' was challenged using two novel approaches based on parametric generalized linear models (GLMs) and 'data-driven' generalized additive models (GAMs). These three approaches (GFs, GLMs, and GAMs) were used to describe seasonal changes in cell numbers in each of the xylem differentiation phases and to calculate the timing of cell development in three conifer species [Picea abies (L.), Pinus sylvestris L., and Abies alba Mill.]. GAMs outperformed GFs and GLMs in describing intra-annual wood formation dynamics, showing two left-skewed bell-shaped curves for division and enlargement, and a right-skewed bimodal curve for thickening. Cell residence times progressively decreased through the season for enlargement, whilst increasing late but rapidly for thickening. These patterns match changes in cell anatomical features within a tree ring, which allows the separation of earlywood and latewood into two distinct cell populations. A novel statistical approach is presented which renews our understanding of xylogenesis, a dynamic biological process in which the rate of cell production interplays with cell residence times in each developmental phase to create complex seasonal patterns.

  1. Iodine Supplementation in Pregnancy and the Dilemma of Ambiguous Recommendations

    DEFF Research Database (Denmark)

    Andersen, Stine Linding; Laurberg, Peter

    2016-01-01

    question is at what level of iodine intake pregnant women should be advised to take iodine-containing supplements. The consensus reached by the WHO/UNICEF/ICCIDD in 2007 was that pregnant women should not be recommended to take iodine-containing supplements if the population in general had been iodine...... sufficient for at least 2 years. However, guidance on this differs between scientific societies. This review discusses iodine supplementation in pregnancy. Based on current evidence, the recommendations given by WHO/UNICEF/ICCIDD in 2007 provide a valid guidance on the use of iodine supplements in pregnant...

  2. The placenta as a compensatory iodine storage organ.

    LENUS (Irish Health Repository)

    Burns, Robert

    2011-05-01

    The production of iodine-containing thyroid hormones necessary for brain development in the fetus depends not only on maternal dietary intake but also on placental iodine transport. The optimum level of iodine nutrition during pregnancy and the proportion of the pregnant population reaching this level have previously been evaluated. Little information exists on the ability of the placenta to either accumulate or store iodine. This study aims to investigate iodine uptake and tissue iodine content within placental tissue obtained from women delivering at term.

  3. Mixed-layered bismuth--oxygen--iodine materials for capture and waste disposal of radioactive iodine

    Energy Technology Data Exchange (ETDEWEB)

    Krumhansl, James L; Nenoff, Tina M

    2015-01-06

    Materials and methods of synthesizing mixed-layered bismuth oxy-iodine materials, which can be synthesized in the presence of aqueous radioactive iodine species found in caustic solutions (e.g. NaOH or KOH). This technology provides a one-step process for both iodine sequestration and storage from nuclear fuel cycles. It results in materials that will be durable for repository conditions much like those found in Waste Isolation Pilot Plant (WIPP) and estimated for Yucca Mountain (YMP). By controlled reactant concentrations, optimized compositions of these mixed-layered bismuth oxy-iodine inorganic materials are produced that have both a high iodine weight percentage and a low solubility in groundwater environments.

  4. Study of establishing disease-syndrome combined with animal model for immune thrombocytopenic purpura without additional conditions

    Directory of Open Access Journals (Sweden)

    Haiyan Lang

    2016-07-01

    Conclusion: According to the syndrome differentiation criteria for disease-syndrome combined model of ITP, the APS-injected animal model of ITP replicated through the passive immune modeling method without additional conditions possesses the characteristics of disease-syndrome combined model. It provides an ideal tool for the development of traditional Chinese medicine pharmacology experiment.

  5. Iodine toxicity and its amelioration.

    Science.gov (United States)

    Baker, David H

    2004-06-01

    Iodine (I) toxicity is rare in animals and humans, but nuclear explosions that give off radioactive I and excessive stable I ingestion in parts of the world where seaweed is consumed represent specialized I toxicity concerns. Chronic overconsumption of I reduces organic binding of I by the thyroid gland, which results in hypothyroidism and goiter. Bromine can replace I on position 5 of both T(3) and T(4) with no loss of thyroid hormone activity. Avian work has also demonstrated that oral bromide salts can reverse the malaise and growth depressions caused by high doses of I (as KI) added as supplements to the diet. Newborn infants by virtue of having immature thyroid glands are most susceptible to I toxicity, whether of stable or radioactive origin. For the latter, the 1986 Chernobyl nuclear accident in Belarus has provided evidence that KI blockage therapy for exposed individuals 18 years of age and younger is effective in minimizing the development of thyroid cancer. Whether bromide therapy has a place in I toxicity situations remains to be determined.

  6. Iodine excretion has decreased in Denmark between 2004 and 2010 - the importance of iodine content in milk

    DEFF Research Database (Denmark)

    Rasmussen, Lone Banke; Carlé, Allan; Jørgensen, Torben

    2014-01-01

    Fortification with the essential trace element iodine is widespread worldwide. In the present study, results on iodine excretion and intake of iodine-rich foods from a cross-sectional study carried out in 2004-5, 4 to 5 years after the implementation of mandatory iodine fortification, were compared...... decreased (P= 0·001). Iodine content was measured in milk sampled in 2000-1 and in 2013. The iodine content was lower in 2013 (12 (sd 3) μg/100 g) compared with that in 2000-1 (16 (sd 6) μg/100 g) (P

  7. Hypothesis: dietary iodine intake in the etiology of cardiovascular disease.

    Science.gov (United States)

    Hoption Cann, Stephen A

    2006-02-01

    This paper reviews evidence suggesting that iodine deficiency can have deleterious effects on the cardiovascular system, and correspondingly, that a higher iodine intake may benefit cardiovascular function. In recent years, public health bodies have aggressively promoted sodium restriction as a means of reducing hypertension and the risk of cardiovascular disease. These inducements have led to a general decline in iodine intake in many developed countries. For example, a United States national health survey conducted in the early 1970s observed that 1 in 40 individuals had urinary iodine levels suggestive of moderate or greater iodine deficiency; twenty years later, moderate to severe iodine deficiency was observed in 1 in 9 participants. Regional iodine intake has been shown to be associated with the prevalence of hypothyroidism and hyperthyroidism, where autoimmune hypothyroidism is the more common of the two in regions with moderate to high iodine intake. Both of these thyroid abnormalities have been shown to negatively affect cardiovascular function. Selenium, an important antioxidant in the thyroid and involved in the metabolism of iodine-containing thyroid hormones, may play an interactive role in the development of these thyroid irregularities, and in turn, cardiovascular disease. Iodine and iodine-rich foods have long been used as a treatment for hypertension and cardiovascular disease; yet, modern randomized studies examining the effects of iodine on cardiovascular disease have not been carried out. The time has come for investigations of sodium, hypertension, and cardiovascular disease to also consider the adverse effects that may result from mild or greater iodine deficiency.

  8. Iodine Supplementation: Usage “with a Grain of Salt”

    Directory of Open Access Journals (Sweden)

    Alessandro Prete

    2015-01-01

    Full Text Available Iodine supplementation through salt iodization is a worldwide, effective strategy for preventing iodine deficiency-related problems. Its safety and efficacy profile has been extensively investigated, and benefits far outweigh the potential iodine-induced risks. Moreover, iodine supplementation during pregnancy in order to avoid brain damage in the newborn is considered a mainstay of preventive medicine. Exposure to high amounts of iodine is actually well tolerated in most cases and can be unrecognized. Nevertheless, at-risk individuals may develop thyroid dysfunction even when they are exposed to increases in iodine intake universally considered as safe. Iodine-induced thyroid disorders include thyroid autoimmunity, thyrotoxicosis, iodine-induced goiter, and hypothyroidism. Moreover, a relationship between iodine intake and histotype distribution of differentiated thyroid cancer has been observed, with a progressive shift from follicular to papillary thyroid cancer. To date, evaluating iodine status in a clinical setting has limitations, and assessing the actual risk for each individual can be challenging, since it is influenced by personal history, genetics, and environmental factors. In conclusion, iodine supplementation programs need to be continued and strengthened, but iodine should be used “with a grain of salt,” because a growing number of susceptible individuals will be exposed to the risk of developing iodine-induced thyroid disorders.

  9. Teratology public affairs committee position paper: iodine deficiency in pregnancy.

    Science.gov (United States)

    Obican, Sarah G; Jahnke, Gloria D; Soldin, Offie P; Scialli, Anthony R

    2012-09-01

    Iodine deficiency is an important nutritional deficiency, with more than 2 billion people worldwide estimated to be at risk. The developing fetus and young children are particularly at risk. During pregnancy and lactation, iodine requirements increase, whether in iodine-poor or iodine-sufficient countries, making the mother and the developing fetus vulnerable. The American Thyroid Association (ATA) recommends 250 micrograms per day of iodine intake for pregnant and lactating women. The thyroid gland is able to adapt to the changes associated with pregnancy as long as sufficient iodine is present. Dietary intake is the sole source of iodine, which is essential to the synthesis of thyroid hormones. Iodine is found in multiple dietary sources including iodized salt, dairy products, seaweed, and fish. Prenatal vitamins containing iodine are a good source of iodine, but iodine content in multivitamin supplements is highly variable. Congenital hypothyroidism is associated with cretinism. Clinical hypothyroidism has been associated with increased risk of poor perinatal outcome including prematurity, low birth weight, miscarriage, preeclampsia, fetal death, and impaired fetal neurocognitive development. Subclinical hypothyroidism is also associated with poor pregnancy outcomes and potential fetal neurocognitive deficits, but the data are more variable than those for clinical hypothyroidism. We concur with the ATA recommendation that all pregnant and lactating women should ingest (through diet and supplements) 250 micrograms of iodine daily. To achieve this goal, we recommend that all pregnant and lactating women take daily iodine supplementation of 150 micrograms.

  10. Biofortification of lettuce (Lactuca sativa L.) with iodine: The effect of iodine form and concentration in the nutrient solution on growth, development and iodine uptake of lettuce grown in water culture

    NARCIS (Netherlands)

    Voogt, W.; Holwerda, H.T.; Khodabaks, M.R.

    2010-01-01

    BACKGROUND: Iodine is an essential trace element for humans. Two billion individuals have insufficient iodine intake. Biofortification of vegetables with iodine offers an excellent opportunity to increase iodine intake by humans. The main aim was to study the effect of iodine form and concentration

  11. Biofortification of lettuce (Lactuca sativa L.) with iodine: The effect of iodine form and concentration in the nutrient solution on growth, development and iodine uptake of lettuce grown in water culture

    NARCIS (Netherlands)

    Voogt, W.; Holwerda, H.T.; Khodabaks, M.R.

    2010-01-01

    BACKGROUND: Iodine is an essential trace element for humans. Two billion individuals have insufficient iodine intake. Biofortification of vegetables with iodine offers an excellent opportunity to increase iodine intake by humans. The main aim was to study the effect of iodine form and concentration

  12. Hardware in the Loop Testing of an Iodine-Fed Hall Thruster

    Science.gov (United States)

    Polzin, Kurt A.; Peeples, Steven R.; Cecil, Jim; Lewis, Brandon L.; Molina Fraticelli, Jose C.; Clark, James P.

    2015-01-01

    CUBESATS are relatively new spacecraft platforms that are typically deployed from a launch vehicle as a secondary payload,1 providing low-cost access to space for a wide range of end-users. These satellites are comprised of building blocks having dimensions of 10x10x10 cm cu and a mass of 1.33 kg (a 1-U size). While providing low-cost access to space, a major operational limitation is the lack of a propulsion system that can fit within a CubeSat and is capable of executing high delta v maneuvers. This makes it difficult to use CubeSats on missions requiring certain types of maneuvers (i.e. formation flying, spacecraft rendezvous). Recently, work has been performed investigating the use of iodine as a propellant for Hall-effect thrusters (HETs) 2 that could subsequently be used to provide a high specific impulse path to CubeSat propulsion. Iodine stores as a dense solid at very low pressures, making it acceptable as a propellant on a secondary payload. It has exceptionally high ?Isp (density times specific impulse), making it an enabling technology for small satellite near-term applications and providing the potential for systems-level advantages over mid-term high power electric propulsion options. Iodine flow can also be thermally regulated, subliming at relatively low temperature ( less than100 C) to yield I2 vapor at or below 50 torr. At low power, the measured performance of an iodine-fed HET is very similar to that of a state-of-the-art xenon-fed thruster. Just as importantly, the current-voltage discharge characteristics of low power iodine-fed and xenon-fed thrusters are remarkably similar, potentially reducing development and qualifications costs by making it possible to use an already-qualified xenon-HET PPU in an iodine-fed system. Finally, a cold surface can be installed in a vacuum test chamber on which expended iodine propellant can deposit. In addition, the temperature doesn't have to be extremely cold to maintain a low vapor pressure in the vacuum

  13. Use of fused deposit modeling for additive manufacturing in hospital facilities: European certification directives.

    Science.gov (United States)

    Otero, Joel J; Vijverman, An; Mommaerts, Maurice Y

    2017-09-01

    The goal of this study was to identify current European Union regulations governing hospital-based use of fused deposit modeling (FDM), as implemented via desktop three-dimensional (3D) printers. Literature and Internet sources were screened, searching for official documents, regulations/legislation, and views of specialized attorneys or consultants regarding European regulations for 3D printing or additive manufacturing (AM) in a healthcare facility. A detailed review of the latest amendment (2016) of the European Parliament and Council legislation for medical devices and its classification was performed, which has regularly updated published guidelines for medical devices, that are classified by type and duration of patient contact. As expected, regulations increase in accordance with the level (I-III) of classification. Custom-made medical devices are subject to different regulations than those controlling serially mass-produced items, as originally specified in 98/79/EC European Parliament and Council legislation (1993) and again recently amended (2016). Healthcare facilities undertaking in-house custom production are not obliged to fully follow the directives as stipulated, given an exception for this scenario (Article 4.4a, 98/79/EC). Patient treatment and diagnosis with the aid of customized 3D printing in a healthcare facility can be performed without fully meeting the European Parliament and Council legislation if the materials used are ISO 10993 certified and article 4.4a applies. Copyright © 2017 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.

  14. Eddy Current Tomography Based on a Finite Difference Forward Model with Additive Regularization

    Science.gov (United States)

    Trillon, A.; Girard, A.; Idier, J.; Goussard, Y.; Sirois, F.; Dubost, S.; Paul, N.

    2010-02-01

    Eddy current tomography is a nondestructive evaluation technique used for characterization of metal components. It is an inverse problem acknowledged as difficult to solve since it is both ill-posed and nonlinear. Our goal is to derive an inversion technique with improved tradeoff between quality of the results, computational requirements and ease of implementation. This is achieved by fully accounting for the nonlinear nature of the forward problem by means of a system of bilinear equations obtained through a finite difference modeling of the problem. The bilinear character of equations with respect to the electric field and the relative conductivity is taken advantage of through a simple contrast source inversion-like scheme. The ill-posedness is dealt with through the addition of regularization terms to the criterion, the form of which is determined according to computational constraints and the piecewise constant nature of the medium. Therefore an edge-preserving functional is selected. The performance of the resulting method is illustrated using 2D synthetic data examples.

  15. Enhancement of colour stability of anthocyanins in model beverages by gum arabic addition.

    Science.gov (United States)

    Chung, Cheryl; Rojanasasithara, Thananunt; Mutilangi, William; McClements, David Julian

    2016-06-15

    This study investigated the potential of gum arabic to improve the stability of anthocyanins that are used in commercial beverages as natural colourants. The degradation of purple carrot anthocyanin in model beverage systems (pH 3.0) containing L-ascorbic acid proceeded with a first-order reaction rate during storage (40 °C for 5 days in light). The addition of gum arabic (0.05-5.0%) significantly enhanced the colour stability of anthocyanin, with the most stable systems observed at intermediate levels (1.5%). A further increase in concentration (>1.5%) reduced its efficacy due to a change in the conformation of the gum arabic molecules that hindered their exposure to the anthocyanins. Fluorescence quenching measurements showed that the anthocyanin could have interacted with the glycoprotein fractions of the gum arabic through hydrogen bonding, resulting in enhanced stability. Overall, this study provides valuable information about enhancing the stability of anthocyanins in beverage systems using natural ingredients.

  16. Influence of the heterogeneous reaction HCl + HOCl on an ozone hole model with hydrocarbon additions

    Science.gov (United States)

    Elliott, Scott; Cicerone, Ralph J.; Turco, Richard P.; Drdla, Katja; Tabazadeh, Azadeh

    1994-02-01

    Injection of ethane or propane has been suggested as a means for reducing ozone loss within the Antarctic vortex because alkanes can convert active chlorine radicals into hydrochloric acid. In kinetic models of vortex chemistry including as heterogeneous processes only the hydrolysis and HCl reactions of ClONO2 and N2O5, parts per billion by volume levels of the light alkanes counteract ozone depletion by sequestering chlorine atoms. Introduction of the surface reaction of HCl with HOCl causes ethane to deepen baseline ozone holes and generally works to impede any mitigation by hydrocarbons. The increased depletion occurs because HCl + HOCl can be driven by HOx radicals released during organic oxidation. Following initial hydrogen abstraction by chlorine, alkane breakdown leads to a net hydrochloric acid activation as the remaining hydrogen atoms enter the photochemical system. Lowering the rate constant for reactions of organic peroxy radicals with ClO to 10-13 cm3 molecule-1 s-1 does not alter results, and the major conclusions are insensitive to the timing of the ethane additions. Ignoring the organic peroxy radical plus ClO reactions entirely restores remediation capabilities by allowing HOx removal independent of HCl. Remediation also returns if early evaporation of polar stratospheric clouds leaves hydrogen atoms trapped in aldehyde intermediates, but real ozone losses are small in such cases.

  17. Statistical inference for the additive hazards model under outcome-dependent sampling.

    Science.gov (United States)

    Yu, Jichang; Liu, Yanyan; Sandler, Dale P; Zhou, Haibo

    2015-09-01

    Cost-effective study design and proper inference procedures for data from such designs are always of particular interests to study investigators. In this article, we propose a biased sampling scheme, an outcome-dependent sampling (ODS) design for survival data with right censoring under the additive hazards model. We develop a weighted pseudo-score estimator for the regression parameters for the proposed design and derive the asymptotic properties of the proposed estimator. We also provide some suggestions for using the proposed method by evaluating the relative efficiency of the proposed method against simple random sampling design and derive the optimal allocation of the subsamples for the proposed design. Simulation studies show that the proposed ODS design is more powerful than other existing designs and the proposed estimator is more efficient than other estimators. We apply our method to analyze a cancer study conducted at NIEHS, the Cancer Incidence and Mortality of Uranium Miners Study, to study the risk of radon exposure to cancer.

  18. Exposure as Duration and Distance in Telematics Motor Insurance Using Generalized Additive Models

    Directory of Open Access Journals (Sweden)

    Jean-Philippe Boucher

    2017-09-01

    Full Text Available In Pay-As-You-Drive (PAYD automobile insurance, the premium is fixed based on the distance traveled, while in usage-based insurance (UBI the driving patterns of the policyholder are also considered. In those schemes, drivers who drive more pay a higher premium compared to those with the same characteristics who drive only occasionally, because the former are more exposed to the risk of accident. In this paper, we analyze the simultaneous effect of the distance traveled and exposure time on the risk of accident by using Generalized Additive Models (GAM. We carry out an empirical application and show that the expected number of claims (1 stabilizes once a certain number of accumulated distance-driven is reached and (2 it is not proportional to the duration of the contract, which is in contradiction to insurance practice. Finally, we propose to use a rating system that takes into account simultaneously exposure time and distance traveled in the premium calculation. We think that this is the trend the automobile insurance market is going to follow with the eruption of telematics data.

  19. Observations of iodine monoxide columns from satellite

    Directory of Open Access Journals (Sweden)

    A. Schönhardt

    2008-02-01

    Full Text Available Iodine species in the troposphere are linked to ozone depletion and new particle formation. In this study, a full year of iodine monoxide (IO columns retrieved from measurements of the SCIAMACHY satellite instrument is presented, coupled with a discussion of their uncertainties and the detection limits. The largest amounts of IO are found near springtime in the Antarctic. A seasonal variation of iodine monoxide in Antarctica is revealed with high values in springtime, slightly less IO in the summer period and again larger amounts in autumn. In winter, no elevated IO levels are found in the areas accessible to satellite measurements. This seasonal cycle is in good agreement with recent ground-based measurements in Antarctica. In the Arctic region, no elevated IO levels were found in the period analysed. This implies that different conditions with respect to iodine release exist in the two Polar Regions. To investigate possible release mechanisms, comparisons of IO columns with those of tropospheric BrO, and ice coverage are described and discussed. Some parallels and interesting differences between IO and BrO temporal and spatial distributions are identified. Overall, the large spatial coverage of satellite retrieved IO data and the availability of a long-term dataset provide new insight about the abundances and distributions of iodine compounds in the troposphere.

  20. [Iodine nutritional status and risk factors for iodine deficiency in infants and children of the french North department].

    Science.gov (United States)

    Pouessel, G; Bouarfa, K; Soudan, B; Sauvage, J; Gottrand, F; Turck, D

    2003-02-01

    Iodine deficiency is responsible for a higher mortality and morbidity in neonates and infants. It has not yet disappeared in European countries, especially in Southern and Eastern Europe. The present study aimed at evaluating the status of iodine nutrition of infants living in the North department (France) and at studying risk factors for iodine deficiency. The study was conducted in primary health care centres in 160 healthy infants aged ten days to six years (mean +/- SD: 17.7 +/- 2.5 months). Data included: familial thyroid disease history, type of feeding at inclusion, timing of introduction of complementary foods, nutritional status (weight, height, head and arm circumference), as well as maternal education level and family socio-economical status. Iodine status was assessed by urinary iodine excretion. Urinary iodine concentration ranged from 4 to 1042 microg/l (median +/- SD: 195,5 +/- 21,6 microg/l). Thirty-eight (24%) of 160 children were iodine deficient (urinary iodine iodine deficiency (50-99 microg/l: 17%), moderate iodine deficiency (20-49 microg/l: 5%), severe iodine deficiency (iodine status and age, sex, geographic origin of the children, as well as social and occupational group of the parents. Breast-feeding did not prevent from iodine deficiency. Iodine status did not differ between the cow's milk fed group and the group that was not fed cow's milk. Formula feeding was associated with iodine deficiency (p = 0,02). Prevalence of severe iodine deficiency was very low in this population. However, iodine status was not optimal.