WorldWideScience

Sample records for assessing lead time

  1. Assessment of realistic nowcasting lead-times based on predictability analysis of Mediterranean Heavy Precipitation Events

    Science.gov (United States)

    Bech, Joan; Berenguer, Marc

    2014-05-01

    Operational quantitative precipitation forecasts (QPF) are provided routinely by weather services or hydrological authorities, particularly those responsible for densely populated regions of small catchments, such as those typically found in Mediterranean areas prone to flash-floods. Specific rainfall values are used as thresholds for issuing warning levels considering different time frameworks (mid-range, short-range, 24h, 1h, etc.), for example 100 mm in 24h or 60 mm in 1h. There is a clear need to determine how feasible is a specific rainfall value for a given lead-time, in particular for very short range forecasts or nowcasts typically obtained from weather radar observations (Pierce et al 2012). In this study we assess which specific nowcast lead-times can be provided for a number of heavy precipitation events (HPE) that affected Catalonia (NE Spain). The nowcasting system we employed generates QPFs through the extrapolation of rainfall fields observed with weather radar following a Lagrangian approach developed and tested successfully in previous studies (Berenguer et al. 2005, 2011).Then QPFs up to 3h are compared with two quality controlled observational data sets: weather radar quantitative precipitation estimates (QPE) and raingauge data. Several high-impact weather HPE were selected including the 7 September 2005 Llobregat Delta river tornado outbreak (Bech et al. 2007) or the 2 November 2008 supercell tornadic thunderstorms (Bech et al. 2011) both producing, among other effects, local flash floods. In these two events there were torrential rainfall rates (30' amounts exceeding 38.2 and 12.3 mm respectively) and 24h accumulation values above 100 mm. A number of verification scores are used to characterize the evolution of precipitation forecast quality with time, which typically presents a decreasing trend but showing an strong dependence on the selected rainfall threshold and integration period. For example considering correlation factors, 30

  2. Lead Time Study,

    Science.gov (United States)

    1982-05-01

    1979, the number of titanium fabrications dropped from 16 to 4, primarily because of the sponge shortage and EPA and OSHA requirements. Non-military...East - Taiwan, Korea, Singapore, Malaysia and Hong Kong. In addition, a significant amount of ceramic parts, lead frames and high technology

  3. Load Dependent Lead Times and Sustainability

    DEFF Research Database (Denmark)

    Pahl, Julia; Voss, Stefan

    2016-01-01

    to prevent decreased quality or waste of production parts and products. This gains importance because waiting times imply longer lead times charging the production system with work in process inventories. Longer lead times can lead to quality losses due to depreciation, so that parts need to be reworked...... if possible or discarded. But return flows of products for rework or remanufacturing actions significantly complicate the production planning process. We analyze sustainability options with respect to lead time management by formulating a comprehensive mathematical model. We consider a deterministic, mixed...

  4. Production Planning with Load Dependent Lead Times

    DEFF Research Database (Denmark)

    Pahl, Julia

    2005-01-01

    Lead times impact the performance of the supply chain significantly. Although there is a large literature concerning queuing models for the analysis of the relationship between capacity utilization and lead times, and there is a substantial literature concerning control and order release policies...... that take lead times into consideration, there have been only few papers describing models at the aggregate planning level that recognize the relationship between the planned utilization of capacity and lead times. In this paper we provide an in-depth discussion of the state-of-the art in this literature......, with particular attention to those models that are appropriate at the aggregate planning level....

  5. Maritime Load Dependent Lead Times - An Analysis

    DEFF Research Database (Denmark)

    Pahl, Julia; Voss, Stefan

    2017-01-01

    in production. Inspired by supply chain planning systems, we analyze the current state of (collaborative) planning in the maritime transport chain with focus on containers. Regarding the problem of congestion, we particularly emphasize on load dependent lead times (LDLT) which are well studied in production....

  6. The Time, Space and Matter of Leading

    DEFF Research Database (Denmark)

    Jørgensen, Kenneth Mølbjerg

    2018-01-01

    This paper develops an ethical framework of leadership learning from Hannah Arendt’s writing. The intention is to identify important principles of a framework of leadership leading that help empower actors to lead themselves and to engage, interact, influence and inspire others through...

  7. Administrative Lead Time at Navy Inventory Control Points

    National Research Council Canada - National Science Library

    Granetto, Paul

    1994-01-01

    .... We also evaluated the internal controls established for administrative lead time and the adequacy of management's implementation of the DoD Internal Management Control Program for monitoring administrative lead time...

  8. Modeling stochastic lead times in multi-echelon systems

    NARCIS (Netherlands)

    Diks, E.B.; Heijden, van der M.C.

    1996-01-01

    In many multi-echelon inventory systems the lead times are random variables. A common and reasonable assumption in most models is that replenishment orders do not cross, which implies that successive lead times are correlated. However, the process which generates such lead times is usually not

  9. Modeling stochastic lead times in multi-echelon systems

    NARCIS (Netherlands)

    Diks, E.B.; van der Heijden, M.C.

    1997-01-01

    In many multi-echelon inventory systems, the lead times are random variables. A common and reasonable assumption in most models is that replenishment orders do not cross, which implies that successive lead times are correlated. However, the process that generates such lead times is usually not well

  10. Editorial: Lead Risk Assessment and Health Effects

    Directory of Open Access Journals (Sweden)

    Howard W. Mielke

    2016-06-01

    Full Text Available In 1980, Clair C. Patterson stated: “Sometime in the near future it probably will be shown that the older urban areas of the United States have been rendered more or less uninhabitable by the millions of tons of poisonous industrial lead residues that have accumulated in cities during the past century”. We live in the near future about which this quote expressed concern. This special volume of 19 papers explores the status of scientific evidence regarding Dr. Patterson’s statement on the habitability of the environments of communities. Authors from 10 countries describe a variety of lead issues in the context of large and small communities, smelter sites, lead industries, lead-based painted houses, and vehicle fuel treated with lead additives dispersed by traffic. These articles represent the microcosm of the larger health issues associated with lead. The challenges of lead risk require a concerted global action for primary prevention.

  11. Periodic capacity management under a lead-time performance constraint

    NARCIS (Netherlands)

    Büyükkaramikli, N.C.; Bertrand, J.W.M.; Ooijen, van H.P.G.

    2013-01-01

    In this paper, we study a production system that operates under a lead-time performance constraint which guarantees the completion of an order before a pre-determined lead-time with a certain probability. The demand arrival times and the service requirements for the orders are random. To reduce the

  12. Assessment and Remediation of Lead Contamination in Senegal

    OpenAIRE

    Donald E. Jones, MS; Assane Diop, BS; Meredith Block, MPA; Alexander Smith-Jones, BS; Andrea Smith-Jones, MS

    2011-01-01

    Background. This paper describes the impact of improper used lead-acid battery (ULAB) handling and disposal. A specific case study is presented describing the field assessment and remediation of lead contamination in a community in Senegal where at least 18 children died from lead poisoning. Objectives. The assessment and remediation process utilized to address the Senegal lead contamination has been used as a model approach to solving used lead-acid battery (ULAB) contamination in other e...

  13. 78 FR 38318 - Integrated Science Assessment for Lead

    Science.gov (United States)

    2013-06-26

    ... ENVIRONMENTAL PROTECTION AGENCY [FRL-9827-4] Integrated Science Assessment for Lead AGENCY... availability of a final document titled, ``Integrated Science Assessment for Lead'' (EPA/600/R-10/075F). The... lead (Pb). DATES: The document will be available on or around June 26, 2013. ADDRESSES: The...

  14. REDUCING LEAD TIME USING FUZZY LOGIC AT JOB SHOP

    Directory of Open Access Journals (Sweden)

    EMİN GÜNDOĞAR

    2000-06-01

    Full Text Available One problem encountering at the job shop scheduling is minimum production size of machine is different from each another. This case increases lead time. A new approach was improved to reduce lead time. In this new approach, the parts, which materials are in stock and orders coming very frequently are assigned to machine to reduce lead time. Due the fact that there are a lot of machine and orders, it is possible to become so1ne probletns. In this paper, fuzzy logic is used to cope with this problem. New approach was simulated at the job sop that has owner 15 machinery and 50 orders. Simulation results showed that new approach reduced lead time between 27.89% and 32.36o/o

  15. PROCESS INNOVATION: HOLISTIC SCENARIOS TO REDUCE TOTAL LEAD TIME

    Directory of Open Access Journals (Sweden)

    Alin POSTEUCĂ

    2015-11-01

    Full Text Available The globalization of markets requires continuous development of business holistic scenarios to ensure acceptable flexibility to satisfy customers. Continuous improvement of supply chain supposes continuous improvement of materials and products lead time and flow, material stocks and finished products stocks and increasing the number of suppliers close by as possible. The contribution of our study is to present holistic scenarios of total lead time improvement and innovation by implementing supply chain policy.

  16. 76 FR 38650 - Draft Integrated Science Assessment for Lead

    Science.gov (United States)

    2011-07-01

    ... Science Assessment for Lead AGENCY: Environmental Protection Agency. ACTION: Notice of extension of public... Lead'' (EPA/600/R-10/075A). The original Federal Register notice announcing the public comment period... review of the National Ambient Air Quality Standards (NAAQS) for Lead. DATES: The public comment period...

  17. Lead intoxication in dogs: risk assessment of feeding dogs trimmings of lead-shot game.

    Science.gov (United States)

    Høgåsen, Helga R; Ørnsrud, Robin; Knutsen, Helle K; Bernhoft, Aksel

    2016-07-25

    Expanding lead-based bullets, commonly used for hunting of big game, produce a scattering of lead particles in the carcass around the wound channel. Trimmings around this channel, which are sometimes fed to dogs, may contain lead particles. The aim of this study was to assess potential health effects of feeding dogs such trimmings. Lead ingestion most commonly causes gastrointestinal and neurological clinical signs, although renal, skeletal, haematological, cardiovascular and biochemical effects have also been reported. Experimental data indicate that a daily dose of around 1 mg lead as lead acetate/kg body weight for ten days may be considered as a Lowest Observed Effect Level in dogs. Acute toxicity documentation from the Centers for Disease Control and Prevention indicates 300 mg/kg body weight as the lowest dose of lead acetate causing death in dogs after oral ingestion. Our assessment suggests that dogs fed trimmings of lead-shot game may be affected by the amounts of lead present, and that even deadly exposure could occasionally occur. The intestinal absorption of lead from bullets was assumed to be 10-80 % of that of lead acetate, reflecting both the variability in particle size and uncertainty about the bioavailability of metallic lead in dogs. Despite data gaps, this study indicates that feeding dogs trimmings of lead-shot game may represent a risk of lead intoxication. More research is needed to assess the exact consequences, if lead-based bullets are still to be used. Meanwhile, we recommend that trimmings close to the wound channel should be made inaccessible to dogs, as well as to other domestic or wild animals.

  18. The impact of project management on nuclear construction lead times

    International Nuclear Information System (INIS)

    Radlaver, M.A.; Bauman, D.S.; Chapel, S.W.

    1985-01-01

    A two-year study of lead times for nuclear power plants found that construction time is affected by six fundamental influences. One of the six is project management. An analysis of construction management teams at 26 nuclear units found that many of the most successful shared five general characteristics: nuclear power experience, skill in project control, adaptability and initiative, commitment to success, and communication and coordination skill

  19. Integrated capacity and inventory management with capacity acquisition lead times

    NARCIS (Netherlands)

    Mincsovics, G.Z.; Tan, T.; Alp, O.

    2009-01-01

    We model a make-to-stock production system that utilizes permanent and contingent capacity to meet non-stationary stochastic demand, where a constant lead time is associated with the acquisition of contingent capacity. We determine the structure of the optimal solution concerning both the

  20. Ultrafast time-resolved spectroscopy of lead halide perovskite films

    Science.gov (United States)

    Idowu, Mopelola A.; Yau, Sung H.; Varnavski, Oleg; Goodson, Theodore

    2015-09-01

    Recently, lead halide perovskites which are organic-inorganic hybrid structures, have been discovered to be highly efficient as light absorbers. Herein, we show the investigation of the excited state dynamics and emission properties of non-stoichiometric precursor formed lead halide perovskites grown by interdiffusion method using steady-state and time-resolved spectroscopic measurements. The influence of the different ratios of the non-stoichiometric precursor solution was examined. The observed photoluminescence properties were correlated with the femtosecond transient absorption measurements.

  1. Lead concentrations and risk exposure assessment in surface soils ...

    African Journals Online (AJOL)

    Lead concentrations and risk exposure assessment in surface soils at residential lands previously used for auto-mechanic and auto-welding activities in Port Harcourt, Nigeria. ... Journal of Applied Sciences and Environmental Management.

  2. Assessment of Copper, Cadmium and Lead in Organical Matrix

    International Nuclear Information System (INIS)

    Gutierrez, Ariel

    2000-08-01

    In this report the electrochemical method of differential pulse anode voltametry redisolution voltametry is used to quantitative assessment of copper, cadmium and lead in solution. The methodology is described in the preparation of samples for measurement

  3. Time evolution of laser-induced breakdown spectrometry of lead

    International Nuclear Information System (INIS)

    Li Zhongwen; Zhang Jianhui

    2011-01-01

    The plasma have been generated by a pulsed Nd: YAG laser at the fundamental wavelength of 1.06 μm ablating a metal lead target in air at atmospheric pressure, and the time resolved emission spectra were gotten. Time evolution of electron temperatures were measured according to the wavelength and relative intensity of spectra; then the electron densities were obtained from the Stark broadening of Pb-line; the time evolution of electron temperatures and electron densities along the direction plumbing the target surface were imaged. The analysis of results showed that electron temperature averaged to 14500 K, electron densities up to 10 17 cm -3 . The characteristics of time evolution of electron temperature and electron density were qualitatively explained from the aspect of generation mechanism of laser-induced plasmas. (authors)

  4. Investigation and assessment of lead slag concrete as nuclear shields

    International Nuclear Information System (INIS)

    Zaghloul, Y.R.

    2009-01-01

    The present work is concerned with the efficiency of heavy weight concrete as a shielding material in constructing nuclear installations as well as for radioactive wastes disposal facilities.In this context, lead slag was used as a replacement for fine aggregates in heavy concrete shields that include local heavy weight aggregates (namely; barite and ilmenite) as well as normal concrete includes dolomite and sand as coarse and fine aggregates, as a reference. The effect of different percentages of lead slag was investigated to assess the produced lead slag concrete as a nuclear shielding material. The different properties (physical, mechanical and nuclear) of the produced lead slag concrete were investigated. The results obtained showed that increasing the lead slag percentage improving the investigated properties of the different concrete mixes. In addition, ilmenite concrete with 20% lead slag showed the best results for all the investigated properties.

  5. Assessment of soil lead exposure in children in Shenyang, China

    International Nuclear Information System (INIS)

    Ren, H.M.; Wang, J.D.; Zhang, X.L.

    2006-01-01

    Soil lead pollution is serious in Shenyang, China. The paper brings together the soil work, the bioaccessibility, and the blood lead data to assess the soil lead exposure in children in Shenyang, China. Approximately 15.25% of the samples were above China Environment Protection Agency guideline concentration for soil Pb to protect human from health risk (350 mg kg -1 ). Pb concentrations varied among use scenarios. The main lead contamination sources are industry emission and automobile exhaust. Bioaccessibility also varied among use scenarios. Children, who ingested soil from industrial area, public parks, kindergarten playground, and commercial area, are more susceptible to soil lead toxicity. The industrial area soil samples presented higher bioaccessibility compared to the other use scenario soil samples contaminated by automobile exhaust. The result also suggested a most significant linear relationship between the level of Pb contamination and the amount of Pb mobilized from soil into ingestion juice. Soil pH seemed to have insignificant influence on bioaccessibility in the present study. Bioaccessibility was mainly controlled by other factors that are not investigated in this study. A linear relationship between children blood lead and soil intestinal bioaccessibility was present in the study. Children who are 4-5 years old are more likely to demonstrate the significant relationship between soil lead bioaccessibility and blood lead as their behaviors place them at greatest risk of soil lead toxicity, and their blood lead levels are more likely to represent recent exposure. - Children were exposed to soil lead and the exposure was assessed by bioaccessibility using in vitro digestion model in a modified version

  6. Three-dimensional binding sites volume assessment during cardiac pacing lead extraction

    Directory of Open Access Journals (Sweden)

    Bich Lien Nguyen

    2015-07-01

    Conclusions: Real-time 3D binding sites assessment is feasible and improves transvenous lead extraction outcomes. Its role as a complementary information requires extensive validation, and might be beneficial for a tailored strategy.

  7. Determination of lead and radioactivity in cosmetics products: Hazard assessment

    Directory of Open Access Journals (Sweden)

    Medhat Moustafa E.

    2015-01-01

    Full Text Available In the proposed work, an investigation on hazard assessment by lead element and natural radioactivity in cosmetic samples collected from various countries is presented. These samples were face powder, eyebrow paint and henna. The lead element in cosmetic samples was determined using particle-induced X-ray emission. Maximum natural radioactivity concentrations of 226Ra and 40K were found in khol and make-up cosmetic samples, respectively. The qualitative analysis of cosmetic samples showed that lead is the most toxic element found in eyebrow paint samples.

  8. Investigation on life cycle assessment of lead and zinc production

    Directory of Open Access Journals (Sweden)

    Sabere Nazari

    2015-12-01

    Full Text Available Lead and zinc production is one of the main predisposing factors of excessive greenhouse gases emissions, air pollution and water consumption. In this paper, the environmental problems of lead and zinc production in Calcimin plant are expressed and life cycle assessment of this plant is assessed. The data regarding the amount of induced global warming and pollution, acidification, and depletion of water resources were collected and discussed. It was concluded that depletion of water resources affected the environment and this was the main issue of the lead and zinc production of this plant. According to the results, in the global warming’s impact category, the proportion of carbon dioxide is more than that of methane. The results also showed that in the acidification’s impact category, the nitrogen oxide proportion is greater compared to that of the sulfur dioxide.

  9. LEADING CHANGES IN ASSESSMENT USING AN EVIDENCE BASED APPROACH

    Directory of Open Access Journals (Sweden)

    J. O. Macaulay

    2015-08-01

    Full Text Available Introduction and objectivesIt is has been widely accepted that assessment of learning is a critical component of education and that assessment drives/guides student learning through shaping study habits and student approaches to learning. However, although most academics would agree that assessment is a critical aspect of their roles as teachers it is often an aspect of teaching that is regarded more as an additional task rather than an integral component of the teaching/learning continuum. An additional impediment to high quality assessment is the non-evidence based-approach to the decision making process. The overall aim of this project was to improve the quality of assessment in Biochemistry and Molecular Biology undergraduate education by promoting high quality assessment.Materials and methodsTo do this we developed and trialled an audit tool for mapping assessment practices. The audit tool was designed to gather data on current assessment practices and identify areas of good practice in which assessment aligned with the learning objectives and areas in need of improvement. This evidence base will then be used to drive change in assessment.Results and conclusionsUsing the assessment mapping tool we have mapped the assessment regime in a Biochemistry and Molecular Biology major at Monash University. Criteria used included: assessment type, format, timing, assessors, provision of feedback, level of learning (Bloom’s, approaches taken to planning assessment. We have mapped assessment of content and the systematic development of higher order learning and skills progression throughout the program of study. The data has enabled us to examine the assessment at unit (course level as well as the vertical development across the major. This information is now being used to inform a review of the units and the major.

  10. Defense Inventory: Opportunities Exist to Improve the Management of DOD's Acquisition Lead Times for Spare Parts

    National Research Council Canada - National Science Library

    2007-01-01

    .... Management of inventory acquisition lead times is important in maintaining cost-effective inventories, budgeting, and having material available when needed, as lead times are DOD's best estimate...

  11. The influence of time on lead toxicity and bioaccumulation determined by the OECD earthworm toxicity test

    International Nuclear Information System (INIS)

    Davies, N.A.Nicola A.; Hodson, M.E.Mark E.; Black, S.Stuart

    2003-01-01

    Timing of lead addition and worms to soil affects the response of the worms to soil affects the response of the worms to lead. - Internationally agreed standard protocols for assessing chemical toxicity of contaminants in soil to worms assume that the test soil does not need to equilibrate with the chemical to be tested prior to the addition of the test organisms and that the chemical will exert any toxic effect upon the test organism within 28 days. Three experiments were carried out to investigate these assumptions. The first experiment was a standard toxicity test where lead nitrate was added to a soil in solution to give a range of concentrations. The mortality of the worms and the concentration of lead in the survivors were determined. The LC 50 s for 14 and 28 days were 5311 and 5395 μg Pb g -1 soil respectively. The second experiment was a timed lead accumulation study with worms cultivated in soil containing either 3000 or 5000 μg Pb g -1 soil . The concentration of lead in the worms was determined at various sampling times. Uptake at both concentrations was linear with time. Worms in the 5000 μg g -1 soil accumulated lead at a faster rate (3.16 μg Pb g -1 tissue day -1 ) than those in the 3000 μg g -1 soil (2.21 μg Pb g -1 tissue day -1 ). The third experiment was a timed experiment with worms cultivated in soil containing 7000 μg Pb g -1 soil . Soil and lead nitrate solution were mixed and stored at 20 deg. C. Worms were added at various times over a 35-day period. The time to death increased from 23 h, when worms were added directly after the lead was added to the soil, to 67 h when worms were added after the soil had equilibrated with the lead for 35 days. In artificially Pb-amended soils the worms accumulate Pb over the duration of their exposure to the Pb. Thus time limited toxicity tests may be terminated before worm body load has reached a toxic level. This could result in under-estimates of the toxicity of Pb to worms. As the equilibration

  12. Nurses: Leading change one day at a time.

    Science.gov (United States)

    Chubbs, Katherine

    2014-06-01

    There has been enormous progress in nursing, and that progress did not come without change. Nurses have two choices: to be a part of developing and leading the change, or to have change happen to them. Copyright © 2014 Longwoods Publishing.

  13. Assessment of the body burden of chelatable lead: a model and its application to lead workers

    Energy Technology Data Exchange (ETDEWEB)

    Araki, S.; Ushio, K.

    1982-05-01

    A hypothetical model was introduced to estimate the body burden of chelatable lead from the mobilisation yield of lead by calcium disodium ethylenediamine tetra-acetate. It was estimated that, on average, 14 and 19% of the body burden was mobilized into the urine during the 24 hours after an injection of 53.4 mumol and 107 mumol CaEDTA per kg bodyweight, respectively. The body burden of chelatable lead ranged from 4 mumol to 120 mumol in lead workers with blood lead concentrations of 0.3-2.9 mumol/kg. There were linear relationships between blood lead concentrations and body burden of chelatable lead on a log scale.

  14. 24 CFR 35.1320 - Lead-based paint inspections, paint testing, risk assessments, lead-hazard screens, and...

    Science.gov (United States)

    2010-04-01

    ... 24 Housing and Urban Development 1 2010-04-01 2010-04-01 false Lead-based paint inspections, paint testing, risk assessments, lead-hazard screens, and reevaluations. 35.1320 Section 35.1320 Housing and Urban Development Office of the Secretary, Department of Housing and Urban Development LEAD-BASED PAINT...

  15. Do Declining Discount Rates lead to Time Inconsistent Economic Advice?

    DEFF Research Database (Denmark)

    Hansen, Anders Chr.

    2006-01-01

    This paper addresses the risk of time inconsistency in economic appraisals related to the use of hyperbolic discounting (declining discount rates) instead of exponential discounting (constant discount rate). Many economists are uneasy about the prospects of potential time inconsistency. The paper...

  16. Indexes of leading climate indicators for impact assessment

    International Nuclear Information System (INIS)

    Easterling, W.E.; Kates, R.W.

    1995-01-01

    Could users of climate information for impact assessment be overlooking an important source of information in climate indicators? We argue that indexes of leading climate indicators of impacts may be usable knowledge for consumers and may provide guidance to the global climate observing community concerning the types of data and information that users need. Five classes of indexes are suggested: Climate Extremes Index (CEI) and Greenhouse Climate Response Index (GCRI) - such are already available from scientists at the US National Climatic Data Center - plus proposed indexes of Hazard Warning, Ecosystem Health, and Energy Demand and Renewable Natural Resources. We conclude that the CEI and GCRI posses several necessary attributes to become usable knowledge; the other indexes have the potential to become usable knowledge, but remain to be implemented with climate data and fully evaluated. 34 refs

  17. Land processes lead to surprising patterns in atmospheric residence time

    Science.gov (United States)

    van der Ent, R.; Tuinenburg, O.

    2017-12-01

    Our research using atmospheric moisture tracking methods shows that the global average atmospheric residence time of evaporation is 8-10 days. This residence time appears to be Gamma distributed with a higher probability of shorter than average residence times and a long tail. As a consequence the median of this residence time is around 5 days. In some places in the world the first few hours/days after evaporation there seems to be a little chance for a moisture particle to precipitate again, which is reflected by a Gamma distribution having a shape parameter below 1. In this study we present global maps of this parameter using different datasets (GLDAS and ERA-Interim). The shape parameter is as such also a measure for the land-atmospheric coupling strength along the path of the atmospheric water particle. We also find that different evaporation components: canopy interception, soil evaporation and transpiration appear to have different residence time distributions. We find a daily cycle in the residence time distribution over land, which is not present over the oceans. In this paper we will show which of the evaporation components is mainly responsible for this daily pattern and thus exhibits the largest daily cycle of land-atmosphere coupling strength.

  18. Lead-Time Models Should Not Be Used to Estimate Overdiagnosis in Cancer Screening

    DEFF Research Database (Denmark)

    Zahl, Per-Henrik; Jørgensen, Karsten Juhl; Gøtzsche, Peter C

    2014-01-01

    screening--the excess-incidence approach and the lead-time approach--that rely on two different lead-time definitions. Overdiagnosis when screening with mammography has varied from 0 to 75 %. We have explained that these differences are mainly caused by using different definitions and methods......Lead-time can mean two different things: Clinical lead-time is the lead-time for clinically relevant tumors; that is, those that are not overdiagnosed. Model-based lead-time is a theoretical construct where the time when the tumor would have caused symptoms is not limited by the person's death....... It is the average time at which the diagnosis is brought forward for both clinically relevant and overdiagnosed cancers. When screening for breast cancer, clinical lead-time is about 1 year, while model-based lead-time varies from 2 to 7 years. There are two different methods to calculate overdiagnosis in cancer...

  19. Assessment of the body burden of chelatable lead: a model and its application to lead workers.

    Science.gov (United States)

    Araki, S; Ushio, K

    1982-01-01

    A hypothetical model was introduced to estimate the body burden of chelatable lead from the mobilisation yield of lead by calcium disodium ethylenediamine tetra-acetate (CaEDTA). It was estimated that, on average, 14 and 19% of the body burden was mobilised into the urine during the 24 hours after an injection of 53.4 mumol (20 mg) and 107 mumol (40 mg) CaEDTA per kg bodyweight, respectively. The body burden of chelatable lead ranged from 4 mumol (0.8 mg) to 120 mumol (24.9 mg) (mean 37 mumol (7.7 mg) in lead workers with blood lead concentrations of 0.3-2.9 mumol/kg (6-60 microgram/100 g) (mean 1.4 mumol/kg (29 microgram/100 g)). There were linear relationships between blood lead concentrations and body burden of chelatable lead on a log scale. PMID:6802167

  20. Real Time Corrosion Monitoring in Lead and Lead-Bismuth Systems

    Energy Technology Data Exchange (ETDEWEB)

    James F. Stubbins; Alan Bolind; Ziang Chen

    2010-02-25

    The objective of this research program is to develop a real-time, in situ corrosion monitoring technique for flowing liquid Pb and eutectic PbBi (LBE) systems in a temperature range of 400 to 650 C. These conditions are relevant to future liquid metal cooled fast reactor operating parameters. THis program was aligned with the Gen IV Reactor initiative to develp technologies to support the design and opertion of a Pb or LBE-cooled fast reactor. The ability to monitor corrosion for protection of structural components is a high priority issue for the safe and prolonged operation of advanced liquid metal fast reactor systems. In those systems, protective oxide layers are intentionally formed and maintained to limit corrosion rates during operation. This program developed a real time, in situ corrosion monitoring tecnique using impedance spectroscopy (IS) technology.

  1. First-passage time: a conception leading to superstatistics

    Directory of Open Access Journals (Sweden)

    V.V.Ryazanov

    2006-01-01

    Full Text Available To describe the nonequilibrium states of a system we introduce a new thermodynamic parameter -- the lifetime (the first passage time of a system. The statistical distributions that can be obtained out of the mesoscopic description characterizing the behaviour of a system by specifying the stochastic processes are written. Superstatistics, introduced in [Beck C., Cohen E.G.D., Physica A, 2003, 322A, 267] as fluctuating quantities of intensive thermodynamical parameters, are obtained from statistical distribution with lifetime (random time to system degeneracy as thermodynamical parameter (and also generalization of superstatistics.

  2. Anticipation of lead time performance in supply chain operations planning

    NARCIS (Netherlands)

    Jansen, M.M.; Kok, de A.G.; Fransoo, J.C.

    2009-01-01

    Whilst being predominantly used in practice, linear and mixed integer programming models for Supply Chain Operations Planning (SCOP) are not well suited for modeling the relationship between the release of work to a production unit and its output over time. In this paper we propose an approach where

  3. Four decades of gasoline lead emissions and control policies in Europe. A retrospective assessment

    Energy Technology Data Exchange (ETDEWEB)

    Von Storch, Hans; Costa-Cabral, Mariza; Hagner, Charlotte; Feser, Frauke [Institute for Coastal Research, GKSS Research Centre, 21502 Geesthacht (Germany); Pacyna, Jozef; Pacyna, Elisabeth [Norwegian Institute for Air Research (NILU) (Norway); Kolb, Steffen [Institute for Journalism and Communication Research, University of Hamburg, Hamburg (Germany)

    2003-07-20

    Over decades, large amounts of the neurotoxin lead were released into the European environment, mostly from gasoline lead additives. Emissions were growing unabatedly until the 1970s, when a series of regulations on the allowed gasoline lead content were adopted. As a result, in the 1990s most gasoline contained only small amounts of lead. We have examined this case of environmental pollution and regulation, and performed a retrospective assessment of the extent of regional-scale lead pollution and the effects of gasoline lead regulations in Europe. With the help of a regional climate model, NCEP re-analyses, spatially disaggregated lead emissions from road traffic and point sources, and various local data, the airborne pathways and depositions of gasoline lead in Europe since 1958 were reconstructed. It turns out that this approach is successful in describing the time-variable, spatially disaggregated deposition of gasoline lead. Additional data from analyses of concentrations in biota, including plant leaves, mussels and human blood, allows an assessment about the impact of the lead phase-out on the quality of the environment. Demonstrating the success of the lead policies, concentrations in leaves and human blood have steadily declined since the early 1980s. At the same time, the economic repercussions that had been feared did not emerge. Instead, the affected mineral oil and car manufacturing industries in Germany (our case-study) were able to deal with the effort without incurring significant extra costs. We suggest that our method of quantitatively reconstructing and anticipating fluxes and depositions of substances can be applied to other relevant substances as well, such as, for example, Persistent Organic Pollutants, radioactive substances or pollens.

  4. Occupational exposure to lead--granulometric distribution of airborne lead in relation to risk assessment.

    Science.gov (United States)

    Carelli, G; Masci, O; Altieri, A; Castellino, N

    1999-07-01

    The amount of airborne lead absorbed by the body during occupational exposure depends not only on lead concentration in workplace air, but also on the granulometric distribution of the aerosol. The Occupational Safety and Health Administration (OSHA) set the lead Permissible Exposure Limit (PEL) at 50 micrograms/m3 on the basis of Bernard's model and a number of assumptions, including assumption "C", which predicts that the first 12.5 micrograms/m3 are made up of fine particles (aerodynamic diameter 1 micron. Occupational exposure to airborne lead at a concentration of 50 micrograms/m3 and a granulometric distribution calculated according to the above mentioned assumption, leads, in the model, to a mean blood level of 40 micrograms/dl. In the present study, we tested the validity of assumption "C" in the environmental air of a factory that manufactured crystal glassware containing 24% lead oxide. An 8-stage impactor was used to measure the particle size of airborne dust collected from personal and area samplings. Results indicate that, on the whole, assumption "C" cannot be considered valid in the work environment investigated in this study. As a result, lead absorption levels in exposed workers may be noticeably different from those predicted by the OSHA model. We therefore suggest that in order to make a correct evaluation of the risk of occupational exposure to lead, it is essential to integrate total airborne lead concentration with a measurement of the granulometric distribution of the aerosol.

  5. Influence of dispatching rules on average production lead time for multi-stage production systems.

    Science.gov (United States)

    Hübl, Alexander; Jodlbauer, Herbert; Altendorfer, Klaus

    2013-08-01

    In this paper the influence of different dispatching rules on the average production lead time is investigated. Two theorems based on covariance between processing time and production lead time are formulated and proved theoretically. Theorem 1 links the average production lead time to the "processing time weighted production lead time" for the multi-stage production systems analytically. The influence of different dispatching rules on average lead time, which is well known from simulation and empirical studies, can be proved theoretically in Theorem 2 for a single stage production system. A simulation study is conducted to gain more insight into the influence of dispatching rules on average production lead time in a multi-stage production system. We find that the "processing time weighted average production lead time" for a multi-stage production system is not invariant of the applied dispatching rule and can be used as a dispatching rule independent indicator for single-stage production systems.

  6. Assessment of the body burden of chelatable lead: a model and its application to lead workers.

    OpenAIRE

    Araki, S; Ushio, K

    1982-01-01

    A hypothetical model was introduced to estimate the body burden of chelatable lead from the mobilisation yield of lead by calcium disodium ethylenediamine tetra-acetate (CaEDTA). It was estimated that, on average, 14 and 19% of the body burden was mobilised into the urine during the 24 hours after an injection of 53.4 mumol (20 mg) and 107 mumol (40 mg) CaEDTA per kg bodyweight, respectively. The body burden of chelatable lead ranged from 4 mumol (0.8 mg) to 120 mumol (24.9 mg) (mean 37 mumol...

  7. Time management situation assessment (TMSA)

    Science.gov (United States)

    Richardson, Michael B.; Ricci, Mark J.

    1992-01-01

    TMSA is a concept prototype developed to support NASA Test Directors (NTDs) in schedule execution monitoring during the later stages of a Shuttle countdown. The program detects qualitative and quantitative constraint violations in near real-time. The next version will support incremental rescheduling and reason over a substantially larger number of scheduled events.

  8. Assessment of Child Lead Exposure in a Philadelphia Community, 2014.

    Science.gov (United States)

    Dignam, Timothy; Pomales, Ana; Werner, Lora; Newbern, E Claire; Hodge, James; Nielsen, Jay; Grober, Aaron; Scruton, Karen; Young, Rand; Kelly, Jack; Brown, Mary Jean

    2018-01-10

    Several urban neighborhoods in Philadelphia, Pennsylvania, have a history of soil, household lead paint, and potential lead-emitting industry contamination. To (1) describe blood lead levels (BLLs) in target neighborhoods, (2) identify risk factors and sources of lead exposure, (3) describe household environmental lead levels, and (4) compare results with existing data. A simple, random, cross-sectional sampling strategy was used to enroll children 8 years or younger living in selected Philadelphia neighborhoods with a history of lead-emitting industry during July 2014. Geometric mean of child BLLs and prevalence of BLLs of 5 μg/dL or more were calculated. Linear and logistic regression analyses were used to ascertain risk factors for elevated BLLs. Among 104 children tested for blood lead, 13 (12.4%; 95% confidence interval [CI], 7.5-20.2) had BLLs of 5 μg/dL or more. The geometric mean BLL was 2.0 μg/dL (95% CI, 1.7-2.3 μg/dL). Higher geometric mean BLLs were significantly associated with front door entryway dust lead content, residence built prior to 1900, and a child currently or ever receiving Medicaid. Seventy-one percent of households exceeded the screening level for soil, 25% had an elevated front door floor dust lead level, 28% had an elevated child play area floor dust lead level, and 14% had an elevated interior window dust lead level. Children in households with 2 to 3 elevated environmental lead samples were more likely to have BLLs of 5 μg/dL or more. A spatial relationship between household proximity to historic lead-emitting facilities and child BLL was not identified. Entryway floor dust lead levels were strongly associated with blood lead levels in participants. Results underscore the importance to make housing lead safe by addressing all lead hazards in and around the home. Reduction of child lead exposure is crucial, and continued blood lead surveillance, testing, and inspection of homes of children with BLLs of 5 μg/dL or more to identify

  9. Time-varying extreme value dependence with application to leading European stock markets

    KAUST Repository

    Castro-Camilo, Daniela

    2018-03-09

    Extremal dependence between international stock markets is of particular interest in today’s global financial landscape. However, previous studies have shown this dependence is not necessarily stationary over time. We concern ourselves with modeling extreme value dependence when that dependence is changing over time, or other suitable covariate. Working within a framework of asymptotic dependence, we introduce a regression model for the angular density of a bivariate extreme value distribution that allows us to assess how extremal dependence evolves over a covariate. We apply the proposed model to assess the dynamics governing extremal dependence of some leading European stock markets over the last three decades, and find evidence of an increase in extremal dependence over recent years.

  10. Time-varying extreme value dependence with application to leading European stock markets

    KAUST Repository

    Castro-Camilo, Daniela; de Carvalho, Miguel; Wadsworth, Jennifer

    2018-01-01

    Extremal dependence between international stock markets is of particular interest in today’s global financial landscape. However, previous studies have shown this dependence is not necessarily stationary over time. We concern ourselves with modeling extreme value dependence when that dependence is changing over time, or other suitable covariate. Working within a framework of asymptotic dependence, we introduce a regression model for the angular density of a bivariate extreme value distribution that allows us to assess how extremal dependence evolves over a covariate. We apply the proposed model to assess the dynamics governing extremal dependence of some leading European stock markets over the last three decades, and find evidence of an increase in extremal dependence over recent years.

  11. Lead Times – Their Behavior and the Impact on Planning and Control in Supply Chains

    Directory of Open Access Journals (Sweden)

    Nielsen Peter

    2017-06-01

    Full Text Available Lead times and their nature have received limited interest in literature despite their large impact on the performance and the management of supply chains. This paper presents a method and a case implementation of the same, to establish the behavior of real lead times in supply chains. The paper explores the behavior of lead times and illustrates how in one particular case they can and should be considered to be independent and identically distributed (i.i.d.. The conclusion is also that the stochastic nature of the lead times contributes more to lead time demand variance than demand variance.

  12. Lead Concentrations and Risk Exposure Assessment in Surface ...

    African Journals Online (AJOL)

    ADOWIE PERE

    µm, < 250 µm, and < 75 µm of surface soils at undeveloped residential lands leased to ... mechanic yards may still be point sources of lead ..... therefore need to conduct a source apportionment ... heavy metals in soil profiles of automobile.

  13. Lead exposure through consumption of big game meat in Quebec, Canada: risk assessment and perception.

    Science.gov (United States)

    Fachehoun, Richard Coovi; Lévesque, Benoit; Dumas, Pierre; St-Louis, Antoine; Dubé, Marjolaine; Ayotte, Pierre

    2015-01-01

    Game meat from animals killed by lead ammunition may expose consumers to lead. We assessed the risk related to lead intake from meat consumption of white-tailed deer and moose killed by lead ammunition and documented the perception of hunters and butchers regarding this potential contamination. Information on cervid meat consumption and risk perception were collected using a mailed self-administrated questionnaire which was addressed to a random sample of Quebec hunters. In parallel, 72 samples of white-tailed deer (n = 35) and moose (n = 37) meats were collected from voluntary hunters and analysed for lead content using inductively coupled plasma-mass spectrometry. A risk assessment for people consuming lead shot game meat was performed using Monte Carlo simulations. Mean lead levels in white-tailed deer and moose killed by lead ammunition were 0.28 and 0.17 mg kg(-1) respectively. Risk assessment based on declared cervid meat consumption revealed that 1.7% of the surveyed hunters would exceed the dose associated with a 1 mmHg increase in systolic blood pressure (SBP). For consumers of moose meat once, twice or three times a week, simulations predicted that 0.5%, 0.9% and 1.5% of adults would be exposed to a dose associated with a 1 mmHg increase in SBP, whereas 0.9%, 1.9% and 3.3% of children would be exposed to a dose associated with 1 point intelligence quotient (IQ) decrease, respectively. For consumers of deer meat once, twice or three times a week, the proportions were 1.6%, 2.9% and 4% for adults and 2.9%, 5.8% and 7.7% for children, respectively. The consumption of meat from cervids killed with lead ammunition may increase lead exposure and its associated health risks. It would be important to inform the population, particularly hunters, about this potential risk and promote the use of lead-free ammunition.

  14. Assessment of Lead Discrimination from CryoSat-2

    DEFF Research Database (Denmark)

    Kildegaard Rose, Stine; Connor, L. N.; Newman, T.

    to spatial and temporal variability. The measurements of sea ice freeboard may be used to estimate sea ice thickness, when combined with examination of leads between ice floes to determine the local sea surface height. With CryoSat-2 (CS), we have the opportunity to measure much more of the Arctic Ocean due...... Topographic Mapper (ATM) laser altimeter data gathered on April 2, 2012, where the NASA P-3 completed an underflight of CS orbit number 10520, north of Alert, Nunavut, Canada. We present a new lead detecting algorithm which was developed using the CS Level1b (L1b) waveforms, and we analyze its capabilities...

  15. Assessing Leading ERP-SAP Implementation in Leading Firms in Indonesia

    Science.gov (United States)

    Syaiful, B.; Gunawan, W.

    2017-01-01

    Enterprise resource planning (ERP) enables to bring critical capabilities to an organisation, however, the implementation of such capabilities is often surrounded with problems. The implementing ERP-SAP in Indonesian enterprises are still facing tremendous challenges with the failure rate can reach more than 80% of the cases. The article examines the common problems faced by the consultants whenever they deal with their clients, from the practical perspectives. The article takes the multiple case studies of the leading enterprises in Indonesia, such as: KS (largest steel producer), GEM (large mining producer), and HS (large retailer), with the aim to identify the root of problems of SAP implementation. The outcome of the study is expected to provide the consultants with the guideline to understand the ERP implementation process in their clients and effective solutions to cope with it.

  16. Leading Formative Assessment Change: A 3-Phase Approach

    Science.gov (United States)

    Northwest Evaluation Association, 2016

    2016-01-01

    If you are seeking greater student engagement and growth, you need to integrate high-impact formative assessment practices into daily instruction. Read the final article in our five-part series to find advice aimed at leaders determined to bring classroom formative assessment practices district wide. Learn: (1) what you MUST consider when…

  17. Research Project: Assessment of Lead in Air of Guatemala City

    International Nuclear Information System (INIS)

    Gutierrez, A.

    1998-01-01

    In this report all the activities concerning to quality of air in the city of Guatemala are considered. By measurements of lead in filters of air sampling using voltametry, the quality of air is going to be compared with international standards

  18. Assessment of lead contamination of farmlands in Abare village ...

    African Journals Online (AJOL)

    DR ADO YUSUF

    Key words: Heavy metals, lead, Zamfara, health risk, soil contamination. ... Similarly, the. Zamfara State Ministry of Environment and Solid Minerals .... The average concentrations of Cd, Pb and Zn were 17.5, ... was found on the interaction between sampling distance .... stalk) are essential components of livestock feed espe-.

  19. Misled about lead: an assessment of online public health education material from Australia's lead mining and smelting towns.

    Science.gov (United States)

    Sullivan, Marianne; Green, Donna

    2016-01-06

    This study assesses the accuracy and comprehensiveness of online public health education materials from the three Australian cities with active lead mines and or smelters: Broken Hill, Mount Isa and Port Pirie. Qualitative content analysis of online Australian material with comparison to international best practice where possible. All materials provided incomplete information about the health effects of lead and pathways of exposure compared to best practice materials. Inconsistent strategies to reduce exposure to lead were identified among the Australian cities, and some evidence-based best practices were not included. The materials normalised environmental lead and neglected to identify that there is no safe level of lead, or that primary prevention is the best strategy for protecting children's health. Health education materials need to clearly state health risks from lead across developmental stages and for sensitive populations, integrate a primary prevention perspective, and provide comprehensive evidence-based recommendations for reducing lead exposure in and around the home. Families who rely on information provided by these online public education materials are likely to be inadequately informed about the importance of protecting their children from exposure to lead and strategies for doing so.

  20. Lead concentrations and risk exposure assessment in surface soils ...

    African Journals Online (AJOL)

    This study investigated lead concentrations in < 250 μm and < 75 μm of deposited dust and< 2000 μm, < 250 μm, and < 75 μm of surface soils at undeveloped residential lands leased to auto-mechanic artisans for a minimum of ten years and estimated exposure risk for children that will reside on the polluted lands after the ...

  1. [Assessment for effect of low level lead-exposure on neurobehavior in workers of printing house].

    Science.gov (United States)

    Niu, Q; Dai, F; Chen, Y

    1998-11-30

    WHO Neurobehavioral Core Test Battery (NCTB) was conducted among 28 lead-exposed workers (mean age 24.84, SD2.85) in printing house and 46 controls (mean age 22.78, SD1.45), in order to assess whether low level lead exposure may be related to neurobehavioral dysfunction. The items of test were: 1. Profile of mood state(POMS), (2) Simple reaction time, (3) Digit span, (4) Santa Anna manual dexterity, (5) Digit simbol, (6) Benton visual retention; and Prusuit aiming test. In all the NCTB test values, there was no significant difference between two groups. Multiple stepwise regression analysis shows that exposure duration is related to neurobehavior scores. Mild lead exposure may affect neurobehavior in some degree but not significant.

  2. Comparative assessment of thermophysical and thermohydraulic characteristics of lead, lead-bismuth and sodium coolants for fast reactors

    International Nuclear Information System (INIS)

    2002-06-01

    All prototype, demonstration and commercial liquid metal cooled fast reactors (LMFRs) have used liquid sodium as a coolant. Sodium cooled systems, operating at low pressure, are characterised by very large thermal margins relative to the coolant boiling temperature and a very low structural material corrosion rate. In spite of the negligible thermal energy stored in the liquid sodium available for release in case of leakage, there is some safety concern because of its chemical reactivity with respect to air and water. Lead, lead-bismuth or other alloys of lead, appear to eliminate these concerns because the chemical reactivity of these coolants with respect to air and water is very low. Some experts believe that conceptually, these systems could be attractive if high corrosion activity inherent in lead, long term materials compatibility and other problems will be resolved. Extensive research and development work is required to meet this goal. Preliminary studies on lead-bismuth and lead cooled reactors and ADS (accelerator driven systems) have been initiated in France, Japan, the United States of America, Italy, and other countries. Considerable experience has been gained in the Russian Federation in the course of development and operation of reactors cooled with lead-bismuth eutectic, in particular, propulsion reactors. Studies on lead cooled fast reactors are also under way in this country. The need to exchange information on alternative fast reactor coolants was a major consideration in the recommendation by the Technical Working Group on Fast Reactors (TWGFRs) to collect, review and document the information on lead and lead-bismuth alloy coolants: technology, thermohydraulics, physical and chemical properties, as well as to make an assessment and comparison with respective sodium characteristics

  3. Quality Improvement, Inventory Management, Lead Time Reduction and Production Scheduling in High-Mix Manufacturing Environments

    Science.gov (United States)

    2017-01-13

    Quality Improvement , Inventory Management, Lead Time Reduction and Production Scheduling in High-mix Manufacturing Environments by Sean Daigle B.S...Mechanical Engineering Chairman, Department Committee on Graduate Theses 2 Quality Improvement , Inventory Management, Lead Time Reduction and... Production Scheduling in High-mix Manufacturing Environments by Sean Daigle Submitted to the Department of Mechanical Engineering on January 13, 2017, in

  4. Integrated vendor-buyer inventory models with inflation and time value of money in controllable lead time

    Directory of Open Access Journals (Sweden)

    Prashant Jindal

    2016-01-01

    Full Text Available In the global critical economic scenario, inflation plays a vital role in deciding optimal pricing of goods in any business entity. This article presents two single-vendor single-buyer integrated supply chain inventory models with inflation and time value of money. Shortage is allowed during the lead-time and it is partially backlogged. Lead time is controllable and can be reduced using crashing cost. In the first model, we consider the demand of lead time follows a normal distribution, and in the second model, it is considered distribution-free. For both cases, our objective is to minimize the integrated system cost by simultaneously optimizing the order quantity, safety factor, lead time and number of lots. The discounted cash flow and classical optimization technique are used to derive the optimal solution for both cases. Numerical examples including the sensitivity analysis of system parameters is provided to validate the results of the supply chain models.

  5. Neighborhood level health risk assessment of lead paint removal activities from elevated steel bridges

    Energy Technology Data Exchange (ETDEWEB)

    Conway, R.F.; Cohen, J.T.; Bowers, T.

    1999-07-01

    The New York City Department of Transportation (NYCDOT) has adopted strict containment and monitoring procedures during paint removal activities on its bridges because of the increasing awareness about lead poisoning in children in urban environments and the potential risk of lead-based paint releases during those activities. NYCDOT owns nearly 800 bridges scattered throughout New York City. Before undertaking paint removal activities as part of its ongoing preventive maintenance and rehabilitation program, NYCDOT recently conducted an analysis to determine the public health risk posed to children living near them. The analysis the first of its kind to assess the actual public health risk potential during both routine operations and upset conditions, or accidental releases evaluated the total and incremental blood lead levels from paint removal activities on more than 5,000 children from 6 months to 6 years old. Increases in baseline blood lead levels were estimated using several models, including EPA's Integrated Exposure Uptake Biokinetic (IEUBK) Model. This model estimates steady-state blood lead levels in children, reflecting exposure to lead in multiple media over an extended period of time. Increases in lead exposure from paint removal activities in the area surrounding the bridges was estimated using EPA's Industrial Source Complex (ISC3) model to calculate ambient air and deposition levels. Potential releases from the containment and ancillary equipment used in the paint removal process were modeled based on different release scenarios ranging from routine operations to complete failure of containment. To estimate the paint removal activities' contribution to long-term exterior dust lead levels (and its related interior component), a stochastic simulation model was developed for each block in the study area.

  6. A note on the catch-up time method for estimating lead or sojourn time in prostate cancer screening

    NARCIS (Netherlands)

    G. Draisma (Gerrit); J.M. van Rosmalen (Joost)

    2013-01-01

    textabstractModels of cancer screening assume that cancers are detectable by screening before being diagnosed clinically through symptoms. The duration of this preclinical phase is called sojourn time, and it determines how much diagnosis might be advanced in time by the screening test (lead time).

  7. Time: Assessing Understanding of Core Ideas

    Science.gov (United States)

    Thomas, Margaret; McDonough, Andrea; Clarkson, Philip; Clarke, Doug

    2016-01-01

    Although an understanding of time is crucial in our society, curriculum documents have an undue emphasis on reading time and little emphasis on core underlying ideas. Given this context, a one-to-one assessment interview, based on a new framework, was developed and administered to investigate students' understanding of core ideas undergirding the…

  8. ADVANCEMENTS IN TIME-SPECTRA ANALYSIS METHODS FOR LEAD SLOWING-DOWN SPECTROSCOPY

    International Nuclear Information System (INIS)

    Smith, Leon E.; Anderson, Kevin K.; Gesh, Christopher J.; Shaver, Mark W.

    2010-01-01

    Direct measurement of Pu in spent nuclear fuel remains a key challenge for safeguarding nuclear fuel cycles of today and tomorrow. Lead slowing-down spectroscopy (LSDS) is an active nondestructive assay method that has the potential to provide independent, direct measurement of Pu and U isotopic mass with an uncertainty lower than the approximately 10 percent typical of today's confirmatory assay methods. Pacific Northwest National Laboratory's (PNNL) previous work to assess the viability of LSDS for the assay of pressurized water reactor (PWR) assemblies indicated that the method could provide direct assay of Pu-239 and U-235 (and possibly Pu-240 and Pu-241) with uncertainties less than a few percent, assuming suitably efficient instrumentation, an intense pulsed neutron source, and improvements in the time-spectra analysis methods used to extract isotopic information from a complex LSDS signal. This previous simulation-based evaluation used relatively simple PWR fuel assembly definitions (e.g. constant burnup across the assembly) and a constant initial enrichment and cooling time. The time-spectra analysis method was founded on a preliminary analytical model of self-shielding intended to correct for assay-signal nonlinearities introduced by attenuation of the interrogating neutron flux within the assembly.

  9. Critical spare parts ordering decisions using conditional reliability and stochastic lead time

    International Nuclear Information System (INIS)

    Godoy, David R.; Pascual, Rodrigo; Knights, Peter

    2013-01-01

    Asset-intensive companies face great pressure to reduce operation costs and increase utilization. This scenario often leads to over-stress on critical equipment and its spare parts associated, affecting availability, reliability, and system performance. As these resources impact considerably on financial and operational structures, the opportunity is given by demand for decision-making methods for the management of spare parts processes. We proposed an ordering decision-aid technique which uses a measurement of spare performance, based on the stress–strength interference theory; which we have called Condition-Based Service Level (CBSL). We focus on Condition Managed Critical Spares (CMS), namely, spares which are expensive, highly reliable, with higher lead times, and are not available in store. As a mitigation measure, CMS are under condition monitoring. The aim of the paper is orienting the decision time for CMS ordering or just continuing the operation. The paper presents a graphic technique which considers a rule for decision based on both condition-based reliability function and a stochastic/fixed lead time. For the stochastic lead time case, results show that technique is effective to determine the time when the system operation is reliable and can withstand the lead time variability, satisfying a desired service level. Additionally, for the constant lead time case, the technique helps to define insurance spares. In conclusion, presented ordering decision rule is useful to asset managers for enhancing the operational continuity affected by spare parts

  10. Performance Assessment Position Paper: Time for Compliance

    International Nuclear Information System (INIS)

    Wilhite, E.L.

    2003-01-01

    This study lays out the historical development of the time frame for a low-level waste disposal facility to demonstrate compliance with the DOE performance objectives and requirements. The study recommends that 1,000 years should be used as the time for compliance for all of the performance objectives and requirements (i.e., for the all-pathways, air pathway, radon emanation, water resource protection and inadvertent intruder analyses) for all low-level waste disposal facility performance assessments at the Savannah River Site

  11. A Time-Walk Correction Method for PET Detectors Based on Leading Edge Discriminators.

    Science.gov (United States)

    Du, Junwei; Schmall, Jeffrey P; Judenhofer, Martin S; Di, Kun; Yang, Yongfeng; Cherry, Simon R

    2017-09-01

    The leading edge timing pick-off technique is the simplest timing extraction method for PET detectors. Due to the inherent time-walk of the leading edge technique, corrections should be made to improve timing resolution, especially for time-of-flight PET. Time-walk correction can be done by utilizing the relationship between the threshold crossing time and the event energy on an event by event basis. In this paper, a time-walk correction method is proposed and evaluated using timing information from two identical detectors both using leading edge discriminators. This differs from other techniques that use an external dedicated reference detector, such as a fast PMT-based detector using constant fraction techniques to pick-off timing information. In our proposed method, one detector was used as reference detector to correct the time-walk of the other detector. Time-walk in the reference detector was minimized by using events within a small energy window (508.5 - 513.5 keV). To validate this method, a coincidence detector pair was assembled using two SensL MicroFB SiPMs and two 2.5 mm × 2.5 mm × 20 mm polished LYSO crystals. Coincidence timing resolutions using different time pick-off techniques were obtained at a bias voltage of 27.5 V and a fixed temperature of 20 °C. The coincidence timing resolution without time-walk correction were 389.0 ± 12.0 ps (425 -650 keV energy window) and 670.2 ± 16.2 ps (250-750 keV energy window). The timing resolution with time-walk correction improved to 367.3 ± 0.5 ps (425 - 650 keV) and 413.7 ± 0.9 ps (250 - 750 keV). For comparison, timing resolutions were 442.8 ± 12.8 ps (425 - 650 keV) and 476.0 ± 13.0 ps (250 - 750 keV) using constant fraction techniques, and 367.3 ± 0.4 ps (425 - 650 keV) and 413.4 ± 0.9 ps (250 - 750 keV) using a reference detector based on the constant fraction technique. These results show that the proposed leading edge based time-walk correction method works well. Timing resolution obtained

  12. Inattentional Deafness: Visual Load Leads to Time-Specific Suppression of Auditory Evoked Responses.

    Science.gov (United States)

    Molloy, Katharine; Griffiths, Timothy D; Chait, Maria; Lavie, Nilli

    2015-12-09

    Due to capacity limits on perception, conditions of high perceptual load lead to reduced processing of unattended stimuli (Lavie et al., 2014). Accumulating work demonstrates the effects of visual perceptual load on visual cortex responses, but the effects on auditory processing remain poorly understood. Here we establish the neural mechanisms underlying "inattentional deafness"--the failure to perceive auditory stimuli under high visual perceptual load. Participants performed a visual search task of low (target dissimilar to nontarget items) or high (target similar to nontarget items) load. On a random subset (50%) of trials, irrelevant tones were presented concurrently with the visual stimuli. Brain activity was recorded with magnetoencephalography, and time-locked responses to the visual search array and to the incidental presence of unattended tones were assessed. High, compared to low, perceptual load led to increased early visual evoked responses (within 100 ms from onset). This was accompanied by reduced early (∼ 100 ms from tone onset) auditory evoked activity in superior temporal sulcus and posterior middle temporal gyrus. A later suppression of the P3 "awareness" response to the tones was also observed under high load. A behavioral experiment revealed reduced tone detection sensitivity under high visual load, indicating that the reduction in neural responses was indeed associated with reduced awareness of the sounds. These findings support a neural account of shared audiovisual resources, which, when depleted under load, leads to failures of sensory perception and awareness. The present work clarifies the neural underpinning of inattentional deafness under high visual load. The findings of near-simultaneous load effects on both visual and auditory evoked responses suggest shared audiovisual processing capacity. Temporary depletion of shared capacity in perceptually demanding visual tasks leads to a momentary reduction in sensory processing of auditory

  13. Decision of Lead-Time Compression and Stable Operation of Supply Chain

    Directory of Open Access Journals (Sweden)

    Songtao Zhang

    2017-01-01

    Full Text Available A cost optimization strategy and a robust control strategy were studied to realize the low-cost robust operation of the supply chain with lead times. Firstly, for the multiple production lead times which existed in the supply chain, a corresponding inventory state model and a supply chain cost model were constructed based on the Takagi-Sugeno fuzzy control system. Then, by considering the actual inventory level, the lead-time compression cost, and the stock-out cost, a cost optimization strategy was proposed. Furthermore, a fuzzy robust control strategy was proposed to realize the flexible switching among the models. Finally, the simulation results show that the total cost of the supply chain could be reduced effectively by the cost optimization strategy, and the stable operation of the supply chain could be realized by the proposed fuzzy robust control strategy.

  14. Superior Reproducibility of the Leading to Leading Edge and Inner to Inner Edge Methods in the Ultrasound Assessment of Maximum Abdominal Aortic Diameter

    DEFF Research Database (Denmark)

    Borgbjerg, Jens; Bøgsted, Martin; Lindholt, Jes S

    2018-01-01

    Objectives: Controversy exists regarding optimal caliper placement in ultrasound assessment of maximum abdominal aortic diameter. This study aimed primarily to determine reproducibility of caliper placement in relation to the aortic wall with the three principal methods: leading to leading edge...

  15. Half Double Methodology – Leading projects to impact in half the time with double the impact

    DEFF Research Database (Denmark)

    Ehlers, Michael; Svejvig, Per

    this presentation to learn about the three core elements of the half-double methodology so that you can lead your projects to double the impact in half the time. Objectives: Summarize the half-double methodology and core elements of impact, flow, and leadership; explain how PMI’s project management tools can......Despite developments in agile methodologies over the last 20 years, the potential for optimization in projects is still significant. Current research shows that there are methodologies that can be used to reduce lead time and increase value creation of projects by 30% or more. Join...

  16. Overestimated lead times in cancer screening has led to substantial underestimation of overdiagnosis

    DEFF Research Database (Denmark)

    Zahl, P-H; Juhl Jørgensen, Karsten; Gøtzsche, P C

    2013-01-01

    Published lead time estimates in breast cancer screening vary from 1 to 7 years and the percentages of overdiagnosis vary from 0 to 75%. The differences are usually explained as random variations. We study how much can be explained by using different definitions and methods.......Published lead time estimates in breast cancer screening vary from 1 to 7 years and the percentages of overdiagnosis vary from 0 to 75%. The differences are usually explained as random variations. We study how much can be explained by using different definitions and methods....

  17. Time trends in burdens of cadmium, lead, and mercury in the population of northern Sweden

    International Nuclear Information System (INIS)

    Wennberg, Maria; Lundh, Thomas; Bergdahl, Ingvar A.; Hallmans, Goeran; Jansson, Jan-Hakan; Stegmayr, Birgitta; Custodio, Hipolito M.; Skerfving, Staffan

    2006-01-01

    The time trends of exposure to heavy metals are not adequately known. This is a worldwide problem with regard to the basis for preventive actions and evaluation of their effects. This study addresses time trends for the three toxic elements cadmium (Cd), mercury (Hg), and lead (Pb). Concentrations in erythrocytes (Ery) were determined in a subsample of the population-based MONICA surveys from 1990, 1994, and 1999 in a total of 600 men and women aged 25-74 years. The study took place in the two northernmost counties in Sweden. To assess the effect of changes in the environment, adjustments were made for life-style factors that are determinants of exposure. Annual decreases of 5-6% were seen for Ery-Pb levels (adjusted for age and changes in alcohol intake) and Ery-Hg levels (adjusted for age and changes in fish intake). Ery-Cd levels (adjusted for age) showed a similar significant decrease in smoking men. It is concluded that for Pb and maybe also Hg the actions against pollution during recent decades have caused a rapid decrease of exposure; for Hg the decreased use of dental amalgam may also have had an influence. For Cd, the decline in Ery-Cd was seen only in smokers, indicating that Cd exposure from tobacco has decreased, while other environmental sources of Cd have not changed significantly. To further improve the health status in Sweden, it is important to decrease the pollution of Cd, and actions against smoking in the community are important

  18. Multilevel Production Systems with Dependent Demand with Uncertainty of Lead Times

    Directory of Open Access Journals (Sweden)

    Haibatolah Sadeghi

    2016-01-01

    Full Text Available This study considers a multilevel assembly system with several components in each sublevel. It is assumed that actual lead time for all components is probabilistic; and periodic order quantity (POQ policy for ordering is utilized. If at a certain level a job is not received at the expected time, a delay is incurred at the delivery of production at this level and this may result in backorders of the finished product. It is assumed in this case that a fixed percentage of the shortage is backlogged and other sales are lost. In the real situation, some but not all customers will wait for backlogged components during a period of shortage, such as for fashionable commodities or high-tech products with the short product life cycle. The objective of this study is to find the planned lead time and periodicity for the total components in order to minimize the expected fixed ordering, holding, and partial backlogging costs for the finished product. In this study, it is assumed that a percentage of components at each level are scrap. A general mathematical model is suggested and the method developed can be used for optimization planned lead time and periodicity for such an MRP system under lead time uncertainties.

  19. Time course of recovery following resistance training leading or not to failure.

    Science.gov (United States)

    Morán-Navarro, Ricardo; Pérez, Carlos E; Mora-Rodríguez, Ricardo; de la Cruz-Sánchez, Ernesto; González-Badillo, Juan José; Sánchez-Medina, Luis; Pallarés, Jesús G

    2017-12-01

    To describe the acute and delayed time course of recovery following resistance training (RT) protocols differing in the number of repetitions (R) performed in each set (S) out of the maximum possible number (P). Ten resistance-trained men undertook three RT protocols [S × R(P)]: (1) 3 × 5(10), (2) 6 × 5(10), and (3) 3 × 10(10) in the bench press (BP) and full squat (SQ) exercises. Selected mechanical and biochemical variables were assessed at seven time points (from - 12 h to + 72 h post-exercise). Countermovement jump height (CMJ) and movement velocity against the load that elicited a 1 m s -1 mean propulsive velocity (V1) and 75% 1RM in the BP and SQ were used as mechanical indicators of neuromuscular performance. Training to muscle failure in each set [3 × 10(10)], even when compared to completing the same total exercise volume [6 × 5(10)], resulted in a significantly higher acute decline of CMJ and velocity against the V1 and 75% 1RM loads in both BP and SQ. In contrast, recovery from the 3 × 5(10) and 6 × 5(10) protocols was significantly faster between 24 and 48 h post-exercise compared to 3 × 10(10). Markers of acute (ammonia, growth hormone) and delayed (creatine kinase) fatigue showed a markedly different course of recovery between protocols, suggesting that training to failure slows down recovery up to 24-48 h post-exercise. RT leading to failure considerably increases the time needed for the recovery of neuromuscular function and metabolic and hormonal homeostasis. Avoiding failure would allow athletes to be in a better neuromuscular condition to undertake a new training session or competition in a shorter period of time.

  20. Reconstructing the life-time lead exposure in children using dentine in deciduous teeth

    Energy Technology Data Exchange (ETDEWEB)

    Shepherd, Thomas J., E-mail: shepherdtj@aol.com [School of Earth and Environment, University of Leeds, Leeds LS2 9JT (United Kingdom); Dirks, Wendy [Centre for Oral Health Research, School of Dental Sciences, Newcastle University, Newcastle upon Tyne NE2 4BW (United Kingdom); Manmee, Charuwan; Hodgson, Susan [Institute of Health and Society, Newcastle University, Newcastle upon Tyne NE2 4AX (United Kingdom); Banks, David A. [School of Earth and Environment, University of Leeds, Leeds LS2 9JT (United Kingdom); Averley, Paul [Centre for Oral Health Research, School of Dental Sciences, Newcastle University, Newcastle upon Tyne NE2 4BW (United Kingdom); Queensway Dental Practice, 170 Queensway, Billingham, Teesside TS23 2NT (United Kingdom); Pless-Mulloli, Tanja [Institute of Health and Society, Newcastle University, Newcastle upon Tyne NE2 4AX (United Kingdom); Newcastle Institute for Research on Sustainability, Newcastle University, Newcastle upon Tyne NE1 7RU (United Kingdom)

    2012-05-15

    Data are presented to demonstrate that the circumpulpal dentine of deciduous teeth can be used to reconstruct a detailed record of childhood exposure to lead. By combining high spatial resolution laser ablation ICP-MS with dental histology, information was acquired on the concentration of lead in dentine from in utero to several years after birth, using a true time template of dentine growth. Time corrected lead analyses for pairs of deciduous molars confirmed that between-tooth variation for the same child was negligible and that meaningful exposure histories can be obtained from a single, multi-point ablation transect on longitudinal sections of individual teeth. For a laser beam of 100 {mu}m diameter, the lead signal for each ablation point represented a time span of 42 days. Simultaneous analyses for Sr, Zn and Mg suggest that the incorporation of Pb into dentine (carbonated apatite) is most likely controlled by nanocrystal growth mechanisms. The study also highlights the importance of discriminating between primary and secondary dentine and the dangers of translating lead analyses into blood lead estimates without determining the age or duration of dentine sampled. Further work is in progress to validate deciduous teeth as blood lead biomarkers. - Highlights: Black-Right-Pointing-Pointer Reconstruction of childhood exposure history to Pb using deciduous tooth dentine. Black-Right-Pointing-Pointer Pb analyses acquired for dentine growth increments of 42 days. Black-Right-Pointing-Pointer Highly correlated Pb concentration profiles for pairs of deciduous molars. Black-Right-Pointing-Pointer Data for Sr, Zn and Mg provide a model for the incorporation of Pb into dentine.

  1. Reconstructing the life-time lead exposure in children using dentine in deciduous teeth

    International Nuclear Information System (INIS)

    Shepherd, Thomas J.; Dirks, Wendy; Manmee, Charuwan; Hodgson, Susan; Banks, David A.; Averley, Paul; Pless-Mulloli, Tanja

    2012-01-01

    Data are presented to demonstrate that the circumpulpal dentine of deciduous teeth can be used to reconstruct a detailed record of childhood exposure to lead. By combining high spatial resolution laser ablation ICP-MS with dental histology, information was acquired on the concentration of lead in dentine from in utero to several years after birth, using a true time template of dentine growth. Time corrected lead analyses for pairs of deciduous molars confirmed that between-tooth variation for the same child was negligible and that meaningful exposure histories can be obtained from a single, multi-point ablation transect on longitudinal sections of individual teeth. For a laser beam of 100 μm diameter, the lead signal for each ablation point represented a time span of 42 days. Simultaneous analyses for Sr, Zn and Mg suggest that the incorporation of Pb into dentine (carbonated apatite) is most likely controlled by nanocrystal growth mechanisms. The study also highlights the importance of discriminating between primary and secondary dentine and the dangers of translating lead analyses into blood lead estimates without determining the age or duration of dentine sampled. Further work is in progress to validate deciduous teeth as blood lead biomarkers. - Highlights: ► Reconstruction of childhood exposure history to Pb using deciduous tooth dentine. ► Pb analyses acquired for dentine growth increments of 42 days. ► Highly correlated Pb concentration profiles for pairs of deciduous molars. ► Data for Sr, Zn and Mg provide a model for the incorporation of Pb into dentine.

  2. Determination of new time-temperature-transformation diagrams for lead-calcium alloys

    Energy Technology Data Exchange (ETDEWEB)

    Rossi, F.; Lambertin, M. [Arts et Metiers Paristech, LaBoMaP, ENSAM, Rue porte de Paris, 71250 Cluny (France); Delfaut-Durut, L. [CEA, centre de Valduc [SEMP, LECM], 21120 Is-sur-Tille (France); Maitre, A. [SPCTS, UFR Sciences et techniques, 87060 Limoges (France); Vilasi, M. [LCSM, Universite Nancy I, 54506 Vandoeuvre les Nancy (France)

    2008-12-01

    The Pb-Ca is an age hardening alloy that allows for an increase in the hardness compared to pure lead. The hardening is obtained after different successive ageing transformations. In addition, this hardening is followed by an overageing which induces a softening. The ageing and overageing transformation mechanisms are now well identified in lead-calcium alloys. In this paper, we propose to represent the domain of stability of each transformation via time-temperature-transformation diagrams for a calcium concentration from 600 to 1280 ppm and in a range of temperatures from -20 to 180 C. These diagrams are constructed with the data obtained by in situ ageing with metallographic observations, hardness and electrical resistance measurements. The specificities of lead-calcium such as its fast ageing at ambient temperature and its overageing over time required the design of specific devices to be able to identify the characteristics of these alloys. (author)

  3. The effects of lead time and visual aids in TTO valuation: a study of the EQ-VT framework

    NARCIS (Netherlands)

    N. Luo (Nan); M. Li (Minghui); E.A. Stolk (Elly); N. Devlin (Nancy)

    2013-01-01

    markdownabstract__Abstract__ __Background__ The effect of lead time in time trade-off (TTO) valuation is not well understood. The purpose of this study was to investigate the effects on health-state valuation of the length of lead time and the way the lead-time TTO task is displayed visually.

  4. 75 FR 69078 - Workshop To Review Draft Materials for the Lead (Pb) Integrated Science Assessment (ISA)

    Science.gov (United States)

    2010-11-10

    ... ENVIRONMENTAL PROTECTION AGENCY [FRL-9224-7] Workshop To Review Draft Materials for the Lead (Pb) Integrated Science Assessment (ISA) AGENCY: Environmental Protection Agency (EPA). ACTION: Notice of Workshop... (NAAQS) for Lead (Pb), EPA is announcing that a workshop to evaluate initial draft materials for the Pb...

  5. Safety stock or safety lead time : coping with unreliability in demand and supply

    NARCIS (Netherlands)

    van Kampen, T.J.; van Donk, D.P.; van der Zee, D.J.

    2010-01-01

    Safety stock and safety lead time are common measures used to cope with uncertainties in demand and supply. Typically, these uncertainties are studied in isolated instances, ignoring settings with uncertainties both in demand and in supply. The current literature largely neglects case study based

  6. Production planning of a perishable product with lead time and non-stationary demand

    NARCIS (Netherlands)

    Pauls-Worm, K.G.J.; Haijema, R.; Hendrix, E.M.T.; Rossi, R.; Vorst, van der J.G.A.J.

    2012-01-01

    We study a production planning problem for a perishable product with a fixed lifetime, under a service-level constraint. The product has a non-stationary stochastic demand. Food supply chains of fresh products like cheese and several crop products, are characterised by long lead times due to

  7. Inventory control in multi-echelon divergent systems with random lead times

    NARCIS (Netherlands)

    Heijden, van der M.C.; Diks, E.B.; Kok, de A.G.

    1996-01-01

    This paper deals with integral inventory control in multi-echelon divergent systems with stochastic lead times. The policy considered is an echelon stock, periodic review, order-up-to (R, S) policy. A computational method is derived to obtain the order-up-to level and the allocation fractions

  8. Use of Six Sigma Methodology to Reduce Appointment Lead-Time in Obstetrics Outpatient Department.

    Science.gov (United States)

    Ortiz Barrios, Miguel A; Felizzola Jiménez, Heriberto

    2016-10-01

    This paper focuses on the issue of longer appointment lead-time in the obstetrics outpatient department of a maternal-child hospital in Colombia. Because of extended appointment lead-time, women with high-risk pregnancy could develop severe complications in their health status and put their babies at risk. This problem was detected through a project selection process explained in this article and to solve it, Six Sigma methodology has been used. First, the process was defined through a SIPOC diagram to identify its input and output variables. Second, six sigma performance indicators were calculated to establish the process baseline. Then, a fishbone diagram was used to determine the possible causes of the problem. These causes were validated with the aid of correlation analysis and other statistical tools. Later, improvement strategies were designed to reduce appointment lead-time in this department. Project results evidenced that average appointment lead-time reduced from 6,89 days to 4,08 days and the deviation standard dropped from 1,57 days to 1,24 days. In this way, the hospital will serve pregnant women faster, which represents a risk reduction of perinatal and maternal mortality.

  9. The Multi-Location Transshipment Problem with Positive Replenishment Lead Times

    NARCIS (Netherlands)

    Y. Gong (Yeming); E. Yucesan

    2006-01-01

    textabstractTransshipments, monitored movements of material at the same echelon of a supply chain, represent an effective pooling mechanism. With a single exception, research on transshipments overlooks replenishment lead times. The only approach for two-location inventory systems with

  10. Fuzzy Control Model and Simulation for Nonlinear Supply Chain System with Lead Times

    Directory of Open Access Journals (Sweden)

    Songtao Zhang

    2017-01-01

    Full Text Available A new fuzzy robust control strategy for the nonlinear supply chain system in the presence of lead times is proposed. Based on Takagi-Sugeno fuzzy control system, the fuzzy control model of the nonlinear supply chain system with lead times is constructed. Additionally, we design a fuzzy robust H∞ control strategy taking the definition of maximal overlapped-rules group into consideration to restrain the impacts such as those caused by lead times, switching actions among submodels, and customers’ stochastic demands. This control strategy can not only guarantee that the nonlinear supply chain system is robustly asymptotically stable but also realize soft switching among subsystems of the nonlinear supply chain to make the less fluctuation of the system variables by introducing the membership function of fuzzy system. The comparisons between the proposed fuzzy robust H∞ control strategy and the robust H∞ control strategy are finally illustrated through numerical simulations on a two-stage nonlinear supply chain with lead times.

  11. Integration of capacity, pricing, and lead-time decisions in a decentralized supply chain

    NARCIS (Netherlands)

    Zhu, Stuart X.

    We consider a decentralized supply chain consisting of a supplier and a retailer facing price- and lead-time-sensitive demand. The decision process is modelled by a Stackelberg game where the supplier, as a leader, determines the capacity and the wholesale price, and the retailer, as a follower,

  12. Simultaneous calibration of ensemble river flow predictions over an entire range of lead times

    Science.gov (United States)

    Hemri, S.; Fundel, F.; Zappa, M.

    2013-10-01

    Probabilistic estimates of future water levels and river discharge are usually simulated with hydrologic models using ensemble weather forecasts as main inputs. As hydrologic models are imperfect and the meteorological ensembles tend to be biased and underdispersed, the ensemble forecasts for river runoff typically are biased and underdispersed, too. Thus, in order to achieve both reliable and sharp predictions statistical postprocessing is required. In this work Bayesian model averaging (BMA) is applied to statistically postprocess ensemble runoff raw forecasts for a catchment in Switzerland, at lead times ranging from 1 to 240 h. The raw forecasts have been obtained using deterministic and ensemble forcing meteorological models with different forecast lead time ranges. First, BMA is applied based on mixtures of univariate normal distributions, subject to the assumption of independence between distinct lead times. Then, the independence assumption is relaxed in order to estimate multivariate runoff forecasts over the entire range of lead times simultaneously, based on a BMA version that uses multivariate normal distributions. Since river runoff is a highly skewed variable, Box-Cox transformations are applied in order to achieve approximate normality. Both univariate and multivariate BMA approaches are able to generate well calibrated probabilistic forecasts that are considerably sharper than climatological forecasts. Additionally, multivariate BMA provides a promising approach for incorporating temporal dependencies into the postprocessed forecasts. Its major advantage against univariate BMA is an increase in reliability when the forecast system is changing due to model availability.

  13. Inventory control in multi-echelon divergent systems with random lead times

    NARCIS (Netherlands)

    van der Heijden, Matthijs C.; Diks, Erik; de Kok, Ton

    1999-01-01

    This paper deals with integral inventory control in multi-echelon divergent systems with stochastic lead times. The policy considered is an echelon stock, periodic review, order-up-to (R, S) policy. A computational method is derived to obtain the order-up-to level and the allocation fractions

  14. Cadmium, lead, and mercury exposure assessment among croatian consumers of free-living game.

    Science.gov (United States)

    Lazarus, Maja; Prevendar Crnić, Andreja; Bilandžić, Nina; Kusak, Josip; Reljić, Slaven

    2014-09-29

    Free-living game can be an important source of dietary cadmium and lead; the question is whether exposure to these two elements is such that it might cause adverse health effects in the consumers. The aim of this study was to estimate dietary exposure to cadmium, lead, and mercury from free-living big game (fallow deer, roe deer, red deer, wild boar, and brown bear), and to mercury from small game (pheasant and hare), hunted in Croatia from 1990 to 2012. The exposure assessment was based on available literature data and our own measurements of metal levels in the tissues of the game, by taking into account different consumption frequencies (four times a year, once a month and once a week). Exposure was expressed as percentage of (provisional) tolerable weekly intake [(P)TWI] values set by the European Food Safety Authority (EFSA). Consumption of game meat (0.002-0.5 % PTWI) and liver (0.005-6 % PTWI) assumed for the general population (four times a year) does not pose a health risk to consumers from the general population, nor does monthly (0.02-6 % PTWI) and weekly (0.1-24 % PTWI) consumption of game meat. However, because of the high percentage of free-living game liver and kidney samples exceeding the legislative limits for cadmium (2-99 %) and lead (1-82 %), people should keep the consumption of certain game species' offal as low as possible. Children and pregnant and lactating women should avoid eating game offal altogether. Free-living game liver could be an important source of cadmium if consumed on a monthly basis (3-74 % TWI), and if consumed weekly (11-297 % TWI), it could even give rise to toxicological concern.

  15. Increased DNA damage in blood cells of rat treated with lead as assessed by comet assay

    Directory of Open Access Journals (Sweden)

    Mohammad Arif

    2008-06-01

    Full Text Available A growing body of evidence suggests that oxidative stress is the key player in the pathogenesis of lead-induced toxicity. The present study investigated lead induced oxidative DNA damage, if any in rat blood cells by alkaline comet assay. Lead was administered intraperitoneally to rats at doses of 25, 50 and 100 mg/kg body weight for 5 days consecutively. Blood collected on day six from sacrificed lead-treated rats was used to assess the extent of DNA damage by comet assay which entailed measurement of comet length, olive tail moment, tail DNA (% and tail length. The results showed that treatment with lead significantly increased DNA damage in a dose-dependent manner. Therefore, our data suggests that lead treatment is associated with oxidative stress-induced DNA damage in rat blood cells which could be used as an early bio-marker of lead-toxicity.

  16. Seismic assessment of a site using the time series method

    International Nuclear Information System (INIS)

    Krutzik, N.J.; Rotaru, I.; Bobei, M.; Mingiuc, C.; Serban, V.; Androne, M.

    1997-01-01

    To increase the safety of a NPP located on a seismic site, the seismic acceleration level to which the NPP should be qualified must be as representative as possible for that site, with a conservative degree of safety but not too exaggerated. The consideration of the seismic events affecting the site as independent events and the use of statistic methods to define some safety levels with very low annual occurrence probability (10 -4 ) may lead to some exaggerations of the seismic safety level. The use of some very high value for the seismic acceleration imposed by the seismic safety levels required by the hazard analysis may lead to very costly technical solutions that can make the plant operation more difficult and increase maintenance costs. The considerations of seismic events as a time series with dependence among the events produced, may lead to a more representative assessment of a NPP site seismic activity and consequently to a prognosis on the seismic level values to which the NPP would be ensured throughout its life-span. That prognosis should consider the actual seismic activity (including small earthquakes in real time) of the focuses that affect the plant site. The paper proposes the applications of Autoregressive Time Series to issue a prognosis on the seismic activity of a focus and presents the analysis on Vrancea focus that affects NPP Cernavoda site, by this method. The paper also presents the manner to analyse the focus activity as per the new approach and it assesses the maximum seismic acceleration that may affect NPP Cernavoda throughout its life-span (∼ 30 years). Development and applications of new mathematical analysis method, both for long - and short - time intervals, may lead to important contributions in the process of foretelling the seismic events in the future. (authors)

  17. An Integrated Multiechelon Logistics Model with Uncertain Delivery Lead Time and Quality Unreliability

    Directory of Open Access Journals (Sweden)

    Ming-Feng Yang

    2016-01-01

    Full Text Available Nowadays, in order to achieve advantages in supply chain management, how to keep inventory in adequate level and how to enhance customer service level are two critical practices for decision makers. Generally, uncertain lead time and defective products have much to do with inventory and service level. Therefore, this study mainly aims at developing a multiechelon integrated just-in-time inventory model with uncertain lead time and imperfect quality to enhance the benefits of the logistics model. In addition, the Ant Colony Algorithm (ACA is established to determine the optimal solutions. Moreover, based on our proposed model and analysis, the ACA is more efficient than Particle Swarm Optimization (PSO and Lingo in SMEIJI model. An example is provided in this study to illustrate how production run and defective rate have an effect on system costs. Finally, the results of our research could provide some managerial insights which support decision makers in real-world operations.

  18. Modeling and analysis for determining optimal suppliers under stochastic lead times

    DEFF Research Database (Denmark)

    Abginehchi, Soheil; Farahani, Reza Zanjirani

    2010-01-01

    systems. The item acquisition lead times of suppliers are random variables. Backorder is allowed and shortage cost is charged based on not only per unit in shortage but also per time unit. Continuous review (s,Q) policy has been assumed. When the inventory level depletes to a reorder level, the total...... order is split among n suppliers. Since the suppliers have different characteristics, the quantity ordered to different suppliers may be different. The problem is to determine the reorder level and quantity ordered to each supplier so that the expected total cost per time unit, including ordering cost...

  19. Stochastic integrated vendor–buyer model with unstable lead time and setup cost

    Directory of Open Access Journals (Sweden)

    Chandra K. Jaggi

    2011-01-01

    Full Text Available This paper presents a new vendor-buyer system where there are different objectives for both sides. The proposed method of this paper is different from the other previously published works since it considers different objectives for both sides. In this paper, the vendor’s emphasis is on the crashing of the setup cost, which not only helps him compete in the market but also provides better services to his customers; and the buyer’s aim is to reduce the lead time, which not only facilitates the buyer to fulfill the customers’ demand on time but also enables him to earn a good reputation in the market or vice versa. In the light of the above stated facts, an integrated vendor-buyer stochastic inventory model is also developed. The propsed model considers two cases for demand during lead time: Case (i Complete demand information, Case (ii Partial demand information. The proposed model jointly optimizes the buyer’s ordered quantity and lead time along with vendor’s setup cost and the number of shipments. The results are demonstrated with the help of numerical examples.

  20. Nuclear reactors' construction costs: The role of lead-time, standardization and technological progress

    International Nuclear Information System (INIS)

    Berthelemy, Michel; Escobar Rangel, Lina

    2013-01-01

    This paper provides the first comparative analysis of nuclear reactor construction costs in France and the United States. Studying the cost of nuclear power has often been a challenge, owing to the lack of reliable data sources and heterogeneity between countries, as well as the long time horizon which requires controlling for input prices and structural changes. We build a simultaneous system of equations for overnight costs and construction time (lead-time) to control for endogeneity, using expected demand variation as an instrument. We argue that benefits from nuclear reactor program standardization can arise through short term coordination gains, when the diversity of nuclear reactors' technologies under construction is low, or through long term benefits from learning spillovers from past reactor construction experience, if those spillovers are limited to similar reactors. We find that overnight construction costs benefit directly from learning spillovers but that these spillovers are only significant for nuclear models built by the same Architect-Engineer (A- E). In addition, we show that the standardization of nuclear reactors under construction has an indirect and positive effect on construction costs through a reduction in lead-time, the latter being one of the main drivers of construction costs. Conversely, we also explore the possibility of learning by searching and find that, contrary to other energy technologies, innovation leads to construction costs increases. (authors)

  1. Optimal base-stock policy for the inventory system with periodic review, backorders and sequential lead times

    DEFF Research Database (Denmark)

    Johansen, Søren Glud; Thorstenson, Anders

    2008-01-01

    We extend well-known formulae for the optimal base stock of the inventory system with continuous review and constant lead time to the case with periodic review and stochastic, sequential lead times. Our extension uses the notion of the 'extended lead time'. The derived performance measures...

  2. Impact of historical mining assessed in soils by kinetic extraction and lead isotopic ratios

    International Nuclear Information System (INIS)

    Camizuli, E.; Monna, F.; Bermond, A.; Manouchehri, N.; Besançon, S.; Losno, R.; Oort, F. van; Labanowski, J.; Perreira, A.; Chateau, C.; Alibert, P.

    2014-01-01

    The aim of this study is to estimate the long-term behaviour of trace metals, in two soils differently impacted by past mining. Topsoils from two 1 km 2 zones in the forested Morvan massif (France) were sampled to assess the spatial distribution of Cd, Cu, Pb and Zn. The first zone had been contaminated by historical mining. As expected, it exhibits higher trace-metal levels and greater spatial heterogeneity than the second non-contaminated zone, supposed to represent the local background. One soil profile from each zone was investigated in detail to estimate metal behaviour, and hence, bioavailability. Kinetic extractions were performed using EDTA on three samples: the A horizon from both soil profiles and the B horizon from the contaminated soil. For all three samples, kinetic extractions can be modelled by two first-order reactions. Similar kinetic behaviour was observed for all metals, but more metal was extracted from the contaminated A horizon than from the B horizon. More surprising is the general predominance of the residual fraction over the “labile” and “less labile” pools. Past anthropogenic inputs may have percolated over time through the soil profiles because of acidic pH conditions. Stable organo-metallic complexes may also have been formed over time, reducing metal availability. These processes are not mutually exclusive. After kinetic extraction, the lead isotopic compositions of the samples exhibited different signatures, related to contamination history and intrinsic soil parameters. However, no variation in lead signature was observed during the extraction experiment, demonstrating that the “labile” and “less labile” lead pools do not differ in terms of origin. Even if trace metals resulting from past mining and metallurgy persist in soils long after these activities have ceased, kinetic extractions suggest that metals, at least for these particular forest soils, do not represent a threat for biota. - Highlights: • Trace

  3. Impact of historical mining assessed in soils by kinetic extraction and lead isotopic ratios

    Energy Technology Data Exchange (ETDEWEB)

    Camizuli, E., E-mail: estelle.camizuli@u-bourgogne.fr [UMR 6298, ArTeHiS, Université de Bourgogne — CNRS — Culture, 6 bd Gabriel, Bat. Gabriel, 21000 Dijon (France); Monna, F. [UMR 6298, ArTeHiS, Université de Bourgogne — CNRS — Culture, 6 bd Gabriel, Bat. Gabriel, 21000 Dijon (France); Bermond, A.; Manouchehri, N.; Besançon, S. [Institut des sciences et industries du vivant et de l' environnement (AgroParisTech), Laboratoire de Chimie Analytique, 16, rue Claude Bernard, 75231 Paris Cedex 05 (France); Losno, R. [UMR 7583, LISA, Universités Paris 7-Paris 12 — CNRS, 61 av. du Gal de Gaulle, 94010 Créteil Cedex (France); Oort, F. van [UR 251, Pessac, Institut National de la Recherche Agronomique, Centre de Versailles-Grignon, RD 10, 78026 Versailles Cedex (France); Labanowski, J. [UMR 7285, IC2MP, Université de Poitiers — CNRS, 4, rue Michel Brunet, 86022 Poitiers (France); Perreira, A. [UMR 6298, ArTeHiS, Université de Bourgogne — CNRS — Culture, 6 bd Gabriel, Bat. Gabriel, 21000 Dijon (France); Chateau, C. [UFR SVTE, Université de Bourgogne, 6 bd Gabriel, Bat. Gabriel, 21000 Dijon (France); Alibert, P. [UMR 6282, Biogeosciences, Université de Bourgogne — CNRS, 6 bd Gabriel, Bat. Gabriel, 21000 Dijon (France)

    2014-02-01

    The aim of this study is to estimate the long-term behaviour of trace metals, in two soils differently impacted by past mining. Topsoils from two 1 km{sup 2} zones in the forested Morvan massif (France) were sampled to assess the spatial distribution of Cd, Cu, Pb and Zn. The first zone had been contaminated by historical mining. As expected, it exhibits higher trace-metal levels and greater spatial heterogeneity than the second non-contaminated zone, supposed to represent the local background. One soil profile from each zone was investigated in detail to estimate metal behaviour, and hence, bioavailability. Kinetic extractions were performed using EDTA on three samples: the A horizon from both soil profiles and the B horizon from the contaminated soil. For all three samples, kinetic extractions can be modelled by two first-order reactions. Similar kinetic behaviour was observed for all metals, but more metal was extracted from the contaminated A horizon than from the B horizon. More surprising is the general predominance of the residual fraction over the “labile” and “less labile” pools. Past anthropogenic inputs may have percolated over time through the soil profiles because of acidic pH conditions. Stable organo-metallic complexes may also have been formed over time, reducing metal availability. These processes are not mutually exclusive. After kinetic extraction, the lead isotopic compositions of the samples exhibited different signatures, related to contamination history and intrinsic soil parameters. However, no variation in lead signature was observed during the extraction experiment, demonstrating that the “labile” and “less labile” lead pools do not differ in terms of origin. Even if trace metals resulting from past mining and metallurgy persist in soils long after these activities have ceased, kinetic extractions suggest that metals, at least for these particular forest soils, do not represent a threat for biota. - Highlights: • Trace

  4. Verification of short lead time forecast models: applied to Kp and Dst forecasting

    Science.gov (United States)

    Wintoft, Peter; Wik, Magnus

    2016-04-01

    In the ongoing EU/H2020 project PROGRESS models that predicts Kp, Dst, and AE from L1 solar wind data will be used as inputs to radiation belt models. The possible lead times from L1 measurements are shorter (10s of minutes to hours) than the typical duration of the physical phenomena that should be forecast. Under these circumstances several metrics fail to single out trivial cases, such as persistence. In this work we explore metrics and approaches for short lead time forecasts. We apply these to current Kp and Dst forecast models. This project has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement No 637302.

  5. Supply Chain Model with Stochastic Lead Time, Trade-Credit Financing, and Transportation Discounts

    Directory of Open Access Journals (Sweden)

    Sung Jun Kim

    2017-01-01

    Full Text Available This model extends a two-echelon supply chain model by considering the trade-credit policy, transportations discount to make a coordination mechanism between transportation discounts, trade-credit financing, number of shipments, quality improvement of products, and reduced setup cost in such a way that the total cost of the whole system can be reduced, where the supplier offers trade-credit-period to the buyer. For buyer, the backorder rate is considered as variable. There are two investments to reduce setup cost and to improve quality of products. The model assumes lead time-dependent backorder rate, where the lead time is stochastic in nature. By using the trade-credit policy, the model gives how the credit-period would be determined to achieve the win-win outcome. An iterative algorithm is designed to obtain the global optimum results. Numerical example and sensitivity analysis are given to illustrate the model.

  6. Real time source term and dose assessment

    International Nuclear Information System (INIS)

    Breznik, B.; Kovac, A.; Mlakar, P.

    2001-01-01

    The Dose Projection Programme is a tool for decision making in case of nuclear emergency. The essential input data for quick emergency evaluation in the case of hypothetical pressurised water reactor accident are following: source term, core damage assessment, fission product radioactivity, release source term and critical exposure pathways for an early phase of the release. A reduced number of radio-nuclides and simplified calculations can be used in dose calculation algorithm. Simple expert system personal computer programme has been developed for the Krsko Nuclear Power Plant for dose projection within the radius of few kilometers from the pressurised water reactor in early phase of an accident. The input data are instantaneous data of core activity, core damage indicators, release fractions, reduction factor of the release pathways, spray operation, release timing, and dispersion coefficient. Main dose projection steps are: accurate in-core radioactivity determination using reactor power input; core damage and in-containment source term assessment based on quick indications of instrumentation or on activity analysis data; user defines release pathway for typical PWR accident scenarius; dose calculation is performed only for exposure pathway critical for decision about evacuation or sheltering in early phase of an accident.(author)

  7. A proposed methodology for the assessment of arsenic, nickel, cadmium and lead levels in ambient air

    Energy Technology Data Exchange (ETDEWEB)

    Santos, Germán, E-mail: santosg@unican.es; Fernández-Olmo, Ignacio

    2016-06-01

    Air quality assessment, required by the European Union (EU) Air Quality Directive, Directive 2008/50/EC, is part of the functions attributed to Environmental Management authorities. Based on the cost and time consumption associated with the experimental works required for the air quality assessment in relation to the EU-regulated metal and metalloids, other methods such as modelling or objective estimation arise as competitive alternatives when, in accordance with the Air Quality Directive, the levels of pollutants permit their use at a specific location. This work investigates the possibility of using statistical models based on Partial Least Squares Regression (PLSR) and Artificial Neural Networks (ANNs) to estimate the levels of arsenic (As), cadmium (Cd), nickel (Ni) and lead (Pb) in ambient air and their application for policy purposes. A methodology comprising the main steps that should be taken into consideration to prepare the input database, develop the model and evaluate their performance is proposed and applied to a case of study in Santander (Spain). It was observed that even though these approaches present some difficulties in estimating the individual sample concentrations, having an equivalent performance they can be considered valid for the estimation of the mean values – those to be compared with the limit/target values – fulfilling the uncertainty requirements in the context of the Air Quality Directive. Additionally, the influence of the consideration of input variables related to atmospheric stability on the performance of the studied statistical models has been determined. Although the consideration of these variables as additional inputs had no effect on As and Cd models, they did yield an improvement for Pb and Ni, especially with regard to ANN models. - Highlights: • EU encourages modelling techniques over measurements for air quality assessment. • A methodology for minor pollutants assessment by statistical modelling is presented.

  8. A proposed methodology for the assessment of arsenic, nickel, cadmium and lead levels in ambient air

    International Nuclear Information System (INIS)

    Santos, Germán; Fernández-Olmo, Ignacio

    2016-01-01

    Air quality assessment, required by the European Union (EU) Air Quality Directive, Directive 2008/50/EC, is part of the functions attributed to Environmental Management authorities. Based on the cost and time consumption associated with the experimental works required for the air quality assessment in relation to the EU-regulated metal and metalloids, other methods such as modelling or objective estimation arise as competitive alternatives when, in accordance with the Air Quality Directive, the levels of pollutants permit their use at a specific location. This work investigates the possibility of using statistical models based on Partial Least Squares Regression (PLSR) and Artificial Neural Networks (ANNs) to estimate the levels of arsenic (As), cadmium (Cd), nickel (Ni) and lead (Pb) in ambient air and their application for policy purposes. A methodology comprising the main steps that should be taken into consideration to prepare the input database, develop the model and evaluate their performance is proposed and applied to a case of study in Santander (Spain). It was observed that even though these approaches present some difficulties in estimating the individual sample concentrations, having an equivalent performance they can be considered valid for the estimation of the mean values – those to be compared with the limit/target values – fulfilling the uncertainty requirements in the context of the Air Quality Directive. Additionally, the influence of the consideration of input variables related to atmospheric stability on the performance of the studied statistical models has been determined. Although the consideration of these variables as additional inputs had no effect on As and Cd models, they did yield an improvement for Pb and Ni, especially with regard to ANN models. - Highlights: • EU encourages modelling techniques over measurements for air quality assessment. • A methodology for minor pollutants assessment by statistical modelling is presented.

  9. Nuclear reactors' construction costs: The role of lead-time, standardization and technological progress

    International Nuclear Information System (INIS)

    Berthélemy, Michel; Escobar Rangel, Lina

    2015-01-01

    This paper provides an econometric analysis of nuclear reactor construction costs in France and the United States based on overnight costs data. We build a simultaneous system of equations for overnight costs and construction time (lead-time) to control for endogeneity, using change in expected electricity demand as instrument. We argue that the construction of nuclear reactors can benefit from standardization gains through two channels. First, short term coordination benefits can arise when the diversity of nuclear reactors' designs under construction is low. Second, long term benefits can occur due to learning spillovers from past constructions of similar reactors. We find that construction costs benefit directly from learning spillovers but that these spillovers are only significant for nuclear models built by the same Architect–Engineer. In addition, we show that the standardization of nuclear reactors under construction has an indirect and positive effect on construction costs through a reduction in lead-time, the latter being one of the main drivers of construction costs. Conversely, we also explore the possibility of learning by searching and find that, contrary to other energy technologies, innovation leads to construction costs increases. -- Highlights: •This paper analyses the determinants of nuclear reactors construction costs and lead-time. •We study short term (coordination gains) and long term (learning by doing) benefits of standardization in France and the US. •Results show that standardization of nuclear programs is a key factor for reducing construction costs. •We also suggest that technological progress has contributed to construction costs escalation

  10. Scheduling rules to achieve lead-time targets in outpatient appointment systems

    OpenAIRE

    Sivakumar, Appa Iyer; Nguyen, Thu Ba Thi; Graves, Stephen C

    2015-01-01

    This paper considers how to schedule appointments for outpatients, for a clinic that is subject to appointment lead-time targets for both new and returning patients. We develop heuristic rules, which are the exact and relaxed appointment scheduling rules, to schedule each new patient appointment (only) in light of uncertainty about future arrivals. The scheduling rules entail two decisions. First, the rules need to determine whether or not a patient's request can be accepted; then, if the req...

  11. Optimal left ventricular lead position assessed with phase analysis on gated myocardial perfusion SPECT

    International Nuclear Information System (INIS)

    Boogers, Mark J.; Chen, Ji; Garcia, Ernest V.; Bommel, Rutger J. van; Borleffs, C.J.W.; Schalij, Martin J.; Wall, Ernst E. van der; Bax, Jeroen J.; Dibbets-Schneider, Petra; Hiel, Bernies van der; Younis, Imad Al

    2011-01-01

    The aim of the current study was to evaluate the relationship between the site of latest mechanical activation as assessed with gated myocardial perfusion SPECT (GMPS), left ventricular (LV) lead position and response to cardiac resynchronization therapy (CRT). The patient population consisted of consecutive patients with advanced heart failure in whom CRT was currently indicated. Before implantation, 2-D echocardiography and GMPS were performed. The echocardiography was performed to assess LV end-systolic volume (LVESV), LV end-diastolic volume (LVEDV) and LV ejection fraction (LVEF). The site of latest mechanical activation was assessed by phase analysis of GMPS studies and related to LV lead position on fluoroscopy. Echocardiography was repeated after 6 months of CRT. CRT response was defined as a decrease of ≥15% in LVESV. Enrolled in the study were 90 patients (72% men, 67±10 years) with advanced heart failure. In 52 patients (58%), the LV lead was positioned at the site of latest mechanical activation (concordant), and in 38 patients (42%) the LV lead was positioned outside the site of latest mechanical activation (discordant). CRT response was significantly more often documented in patients with a concordant LV lead position than in patients with a discordant LV lead position (79% vs. 26%, p<0.01). After 6 months, patients with a concordant LV lead position showed significant improvement in LVEF, LVESV and LVEDV (p<0.05), whereas patients with a discordant LV lead position showed no significant improvement in these variables. Patients with a concordant LV lead position showed significant improvement in LV volumes and LV systolic function, whereas patients with a discordant LV lead position showed no significant improvements. (orig.)

  12. Reducing of Manufacturing Lead Time by Implementation of Lean Manufacturing Principles

    Directory of Open Access Journals (Sweden)

    Hussein Salem Ketan

    2015-08-01

    Full Text Available Many organizations today are interesting to implementing lean manufacturing principles that should enable them to eliminating the wastes to reducing a manufacturing lead time. This paper concentrates on increasing the competitive level of the company in globalization markets and improving of the productivity by reducing the manufacturing lead time. This will be by using the main tool of lean manufacturing which is value stream mapping (VSM to identifying all the activities of manufacturing process (value and non-value added activities to reducing elimination of wastes (non-value added activities by converting a manufacturing system to pull instead of push by applying some of pull system strategies as kanban and first on first out lane (FIFO. ARENA software is used to simulate the current and future state. This work is executed in the state company for electrical industries in Baghdad. The obtained results of the application showed that implementation of lean principles helped on reducing of a manufacturing lead time by 33%.

  13. Strategic Inventory Positioning in BOM with Multiple Parents Using ASR Lead Time

    Directory of Open Access Journals (Sweden)

    Jingjing Jiang

    2016-01-01

    Full Text Available In order to meet the lead time that the customers require, work-in-process inventory (WIPI is necessary at almost every station in most make-to-order manufacturing. Depending on the station network configuration and lead time at each station, some of the WIPI do not contribute to reducing the manufacturing lead time of the final product at all. Therefore, it is important to identify the optimal set of stations to hold WIPI such that the total inventory holding cost is minimized, while the required due date for the final product is met. The authors have presented a model to determine the optimal position and quantity of WIPI for a given simple bill of material (S-BOM, in which any part in the BOM has only one immediate parent node. In this paper, we extend the previous study to the general BOM (G-BOM in which parts in the BOM can have more than one immediate parent and present a new solution procedure using genetic algorithm.

  14. Enhancing Nursing Staffing Forecasting With Safety Stock Over Lead Time Modeling.

    Science.gov (United States)

    McNair, Douglas S

    2015-01-01

    In balancing competing priorities, it is essential that nursing staffing provide enough nurses to safely and effectively care for the patients. Mathematical models to predict optimal "safety stocks" have been routine in supply chain management for many years but have up to now not been applied in nursing workforce management. There are various aspects that exhibit similarities between the 2 disciplines, such as an evolving demand forecast according to acuity and the fact that provisioning "stock" to meet demand in a future period has nonzero variable lead time. Under assumptions about the forecasts (eg, the demand process is well fit as an autoregressive process) and about the labor supply process (≥1 shifts' lead time), we show that safety stock over lead time for such systems is effectively equivalent to the corresponding well-studied problem for systems with stationary demand bounds and base stock policies. Hence, we can apply existing models from supply chain analytics to find the optimal safety levels of nurse staffing. We use a case study with real data to demonstrate that there are significant benefits from the inclusion of the forecast process when determining the optimal safety stocks.

  15. Application of IEUBK model in lead risk assessment of children aged 61–84 months old in central China

    Energy Technology Data Exchange (ETDEWEB)

    Li, Yanyan [MOE Key Lab of Environment and Health, Institute of Environmental Medicine, School of Public Health, Tongji Medical College, Huazhong University of Science & Technology, Wuhan, Hubei (China); Hu, Jia [Suzhou Center for Disease Prevention and Control, Suzhou, Jiangsu (China); Wu, Wei [MOE Key Lab of Environment and Health, Institute of Environmental Medicine, School of Public Health, Tongji Medical College, Huazhong University of Science & Technology, Wuhan, Hubei (China); Liu, Shuyun [Department of Epidemiology and Biostatistics, School of Public Health, Tongji Medical College, Huazhong University of Science & Technology, Wuhan, Hubei (China); Li, Mei [Hanyang Center for Disease Prevention and Control, Wuhan, Hubei (China); Yao, Na; Chen, Jianwei [MOE Key Lab of Environment and Health, Institute of Environmental Medicine, School of Public Health, Tongji Medical College, Huazhong University of Science & Technology, Wuhan, Hubei (China); Ye, Linxiang [Department of Epidemiology and Biostatistics, School of Public Health, Tongji Medical College, Huazhong University of Science & Technology, Wuhan, Hubei (China); Wang, Qi, E-mail: lwq95@126.com [MOE Key Lab of Environment and Health, Institute of Environmental Medicine, School of Public Health, Tongji Medical College, Huazhong University of Science & Technology, Wuhan, Hubei (China); Department of Epidemiology and Biostatistics, School of Public Health, Tongji Medical College, Huazhong University of Science & Technology, Wuhan, Hubei (China); Zhou, Yikai, E-mail: zhouyk@mails.tjmu.edu.cn [MOE Key Lab of Environment and Health, Institute of Environmental Medicine, School of Public Health, Tongji Medical College, Huazhong University of Science & Technology, Wuhan, Hubei (China)

    2016-01-15

    Few studies have focused on the accuracy of using the Integrated Exposure Uptake Biokinetic (IEUBK) model in Chinese children with site- and age-specific exposure data. This study aimed to validate the accuracy and sensitivity of the IEUBK model in lead risk assessment of Chinese children aged 61–84 months old. A total of 760 children were enrolled from two respective counties in Central China by using random cluster sampling method. Blood lead levels (BLLs) of all subjects were determined using graphite furnace atomic absorption spectrometry, as well as that in the environmental media, such as air, drinking water, soil, dust and food. Age- and site-specific time-activity patterns and water consumption were evaluated by using questionnaires for children. Exposure parameters including outdoor and indoor activity time, ventilation rate and water consumption in this study were different from the default values of the IEUBK model. Statistical analysis revealed no significant differences between the predicted and observed BLLs. Diet and soil/dust lead intake contributed approximately 83.39% (57.40%–93.84% range) and 15.18% (3.25%–41.60% range) of total lead intake, respectively. These findings showed that the IEUBK model is suitable for lead risk assessment of Chinese children aged 61–84 months old and diet acts as an important lead source. - Highlights: • The first time to fit and discuss the IEUBK model in China based on comprehensive local children exposure parameters. • Two different exposure scenarios to apply the IEUBK model in different conditions. • The first time to report the ventilation rate in Chinese children aged 61 to 84 months. • Highlight the role of dietary to lead intake for Chinese children.

  16. Application of IEUBK model in lead risk assessment of children aged 61–84 months old in central China

    International Nuclear Information System (INIS)

    Li, Yanyan; Hu, Jia; Wu, Wei; Liu, Shuyun; Li, Mei; Yao, Na; Chen, Jianwei; Ye, Linxiang; Wang, Qi; Zhou, Yikai

    2016-01-01

    Few studies have focused on the accuracy of using the Integrated Exposure Uptake Biokinetic (IEUBK) model in Chinese children with site- and age-specific exposure data. This study aimed to validate the accuracy and sensitivity of the IEUBK model in lead risk assessment of Chinese children aged 61–84 months old. A total of 760 children were enrolled from two respective counties in Central China by using random cluster sampling method. Blood lead levels (BLLs) of all subjects were determined using graphite furnace atomic absorption spectrometry, as well as that in the environmental media, such as air, drinking water, soil, dust and food. Age- and site-specific time-activity patterns and water consumption were evaluated by using questionnaires for children. Exposure parameters including outdoor and indoor activity time, ventilation rate and water consumption in this study were different from the default values of the IEUBK model. Statistical analysis revealed no significant differences between the predicted and observed BLLs. Diet and soil/dust lead intake contributed approximately 83.39% (57.40%–93.84% range) and 15.18% (3.25%–41.60% range) of total lead intake, respectively. These findings showed that the IEUBK model is suitable for lead risk assessment of Chinese children aged 61–84 months old and diet acts as an important lead source. - Highlights: • The first time to fit and discuss the IEUBK model in China based on comprehensive local children exposure parameters. • Two different exposure scenarios to apply the IEUBK model in different conditions. • The first time to report the ventilation rate in Chinese children aged 61 to 84 months. • Highlight the role of dietary to lead intake for Chinese children.

  17. Study on residual discharge time of lead-acid battery based on fitting method

    Science.gov (United States)

    Liu, Bing; Yu, Wangwang; Jin, Yueqiang; Wang, Shuying

    2017-05-01

    This paper use the method of fitting to discuss the data of C problem of mathematical modeling in 2016, the residual discharge time model of lead-acid battery with 20A,30A,…,100A constant current discharge is obtained, and the discharge time model of discharge under arbitrary constant current is presented. The mean relative error of the model is calculated to be about 3%, which shows that the model has high accuracy. This model can provide a basis for optimizing the adaptation of power system to the electrical motor vehicle.

  18. The M/M/1 queue with inventory, lost sale and general lead times

    DEFF Research Database (Denmark)

    Saffari, Mohammad; Asmussen, Søren; Haji, Rasoul

    We consider an M/M/1 queueing system with inventory under the (r,Q) policy and with lost sales, in which demands occur according to a Poisson process and service times are exponentially distributed. All arriving customers during stockout are lost. We derive the stationary distributions of the joint...... queue length (number of customers in the system) and on-hand inventory when lead times are random variables and can take various distributions. The derived stationary distributions are used to formulate long-run average performance measures and cost functions in some numerical examples....

  19. An assessment of contemporary atomic spectroscopic techniques for the determination of lead in blood and urine matrices

    Science.gov (United States)

    Parsons, Patrick J.; Geraghty, Ciaran; Verostek, Mary Frances

    2001-09-01

    The preparation and validation of a number of clinical reference materials for the determination of lead in blood and urine is described. Four candidate blood lead reference materials (Lots, 047-050), and four candidate urine lead reference materials (Lots, 034, 035, 037 and 038), containing physiologically-bound lead at clinically relevant concentrations, were circulated to up to 21 selected laboratories specializing in this analysis. Results from two interlaboratory studies were used to establish certified values and uncertainty estimates for these reference materials. These data also provided an assessment of current laboratory techniques for the measurement of lead in blood and urine. For the blood lead measurements, four laboratories used electrothermal atomization AAS, three used anodic stripping voltammetry and one used both ETAAS and ICP-MS. For the urine lead measurements, 11 laboratories used ETAAS (most with Zeeman background correction) and 10 used ICP-MS. Certified blood lead concentrations, ±S.D., ranged from 5.9±0.4 μg/dl (0.28±0.02 μmol/l) to 76.0±2.2 μg/dl (3.67±0.11 μmol/l) and urine lead concentrations ranged from 98±5 μg/l (0.47±0.02 μmol/l) to 641±36 μg/l (3.09±0.17 μmol/l). The highest concentration blood lead material was subjected to multiple analyses using ETAAS over an extended time period. The data indicate that more stringent internal quality control practices are necessary to improve long-term precision. While the certification of blood lead materials was accomplished in a manner consistent with established practices, the urine lead materials proved more troublesome, particularly at concentrations above 600 μg/l (2.90 μmol/l).

  20. Linking geology and health sciences to assess childhood lead poisoning from artisanal gold mining in Nigeria

    Science.gov (United States)

    Plumlee, Geoffrey S.; Durant, James T.; Morman, Suzette A.; Neri, Antonio; Wolf, Ruth E.; Dooyema, Carrie A.; Hageman, Philip L.; Lowers, Heather; Fernette, Gregory L.; Meeker, Gregory P.; Benzel, William M.; Driscoll, Rhonda L.; Berry, Cyrus J.; Crock, James G.; Goldstein, Harland L.; Adams, Monique; Bartrem, Casey L.; Tirima, Simba; Behrooz, Behbod; von Lindern, Ian; Brown, Mary Jean

    2013-01-01

    Background: In 2010, Médecins Sans Frontières discovered a lead poisoning outbreak linked to artisanal gold processing in northwestern Nigeria. The outbreak has killed approximately 400 young children and affected thousands more. Objectives: Our aim was to undertake an interdisciplinary geological- and health-science assessment to clarify lead sources and exposure pathways, identify additional toxicants of concern and populations at risk, and examine potential for similar lead poisoning globally. Methods: We applied diverse analytical methods to ore samples, soil and sweep samples from villages and family compounds, and plant foodstuff samples. Results: Natural weathering of lead-rich gold ores before mining formed abundant, highly gastric-bioaccessible lead carbonates. The same fingerprint of lead minerals found in all sample types confirms that ore processing caused extreme contamination, with up to 185,000 ppm lead in soils/sweep samples and up to 145 ppm lead in plant foodstuffs. Incidental ingestion of soils via hand-to-mouth transmission and of dusts cleared from the respiratory tract is the dominant exposure pathway. Consumption of water and foodstuffs contaminated by the processing is likely lesser, but these are still significant exposure pathways. Although young children suffered the most immediate and severe consequences, results indicate that older children, adult workers, pregnant women, and breastfed infants are also at risk for lead poisoning. Mercury, arsenic, manganese, antimony, and crystalline silica exposures pose additional health threats. Conclusions: Results inform ongoing efforts in Nigeria to assess lead contamination and poisoning, treat victims, mitigate exposures, and remediate contamination. Ore deposit geology, pre-mining weathering, and burgeoning artisanal mining may combine to cause similar lead poisoning disasters elsewhere globally.

  1. Linking geological and health sciences to assess childhood lead poisoning from artisanal gold mining in Nigeria.

    Science.gov (United States)

    Plumlee, Geoffrey S; Durant, James T; Morman, Suzette A; Neri, Antonio; Wolf, Ruth E; Dooyema, Carrie A; Hageman, Philip L; Lowers, Heather A; Fernette, Gregory L; Meeker, Gregory P; Benzel, William M; Driscoll, Rhonda L; Berry, Cyrus J; Crock, James G; Goldstein, Harland L; Adams, Monique; Bartrem, Casey L; Tirima, Simba; Behbod, Behrooz; von Lindern, Ian; Brown, Mary Jean

    2013-06-01

    In 2010, Médecins Sans Frontières discovered a lead poisoning outbreak linked to artisanal gold processing in northwestern Nigeria. The outbreak has killed approximately 400 young children and affected thousands more. Our aim was to undertake an interdisciplinary geological- and health-science assessment to clarify lead sources and exposure pathways, identify additional toxicants of concern and populations at risk, and examine potential for similar lead poisoning globally. We applied diverse analytical methods to ore samples, soil and sweep samples from villages and family compounds, and plant foodstuff samples. Natural weathering of lead-rich gold ores before mining formed abundant, highly gastric-bioaccessible lead carbonates. The same fingerprint of lead minerals found in all sample types confirms that ore processing caused extreme contamination, with up to 185,000 ppm lead in soils/sweep samples and up to 145 ppm lead in plant foodstuffs. Incidental ingestion of soils via hand-to-mouth transmission and of dusts cleared from the respiratory tract is the dominant exposure pathway. Consumption of water and foodstuffs contaminated by the processing is likely lesser, but these are still significant exposure pathways. Although young children suffered the most immediate and severe consequences, results indicate that older children, adult workers, pregnant women, and breastfed infants are also at risk for lead poisoning. Mercury, arsenic, manganese, antimony, and crystalline silica exposures pose additional health threats. Results inform ongoing efforts in Nigeria to assess lead contamination and poisoning, treat victims, mitigate exposures, and remediate contamination. Ore deposit geology, pre-mining weathering, and burgeoning artisanal mining may combine to cause similar lead poisoning disasters elsewhere globally.

  2. Linking Geological and Health Sciences to Assess Childhood Lead Poisoning from Artisanal Gold Mining in Nigeria

    Science.gov (United States)

    Durant, James T.; Morman, Suzette A.; Neri, Antonio; Wolf, Ruth E.; Dooyema, Carrie A.; Hageman, Philip L.; Lowers, Heather A.; Fernette, Gregory L.; Meeker, Gregory P.; Benzel, William M.; Driscoll, Rhonda L.; Berry, Cyrus J.; Crock, James G.; Goldstein, Harland L.; Adams, Monique; Bartrem, Casey L.; Tirima, Simba; Behbod, Behrooz; von Lindern, Ian; Brown, Mary Jean

    2013-01-01

    Background: In 2010, Médecins Sans Frontières discovered a lead poisoning outbreak linked to artisanal gold processing in northwestern Nigeria. The outbreak has killed approximately 400 young children and affected thousands more. Objectives: Our aim was to undertake an interdisciplinary geological- and health-science assessment to clarify lead sources and exposure pathways, identify additional toxicants of concern and populations at risk, and examine potential for similar lead poisoning globally. Methods: We applied diverse analytical methods to ore samples, soil and sweep samples from villages and family compounds, and plant foodstuff samples. Results: Natural weathering of lead-rich gold ores before mining formed abundant, highly gastric-bioaccessible lead carbonates. The same fingerprint of lead minerals found in all sample types confirms that ore processing caused extreme contamination, with up to 185,000 ppm lead in soils/sweep samples and up to 145 ppm lead in plant foodstuffs. Incidental ingestion of soils via hand-to-mouth transmission and of dusts cleared from the respiratory tract is the dominant exposure pathway. Consumption of water and foodstuffs contaminated by the processing is likely lesser, but these are still significant exposure pathways. Although young children suffered the most immediate and severe consequences, results indicate that older children, adult workers, pregnant women, and breastfed infants are also at risk for lead poisoning. Mercury, arsenic, manganese, antimony, and crystalline silica exposures pose additional health threats. Conclusions: Results inform ongoing efforts in Nigeria to assess lead contamination and poisoning, treat victims, mitigate exposures, and remediate contamination. Ore deposit geology, pre-mining weathering, and burgeoning artisanal mining may combine to cause similar lead poisoning disasters elsewhere globally. PMID:23524139

  3. Leading the Transition from the Alternate Assessment Based on Modified Achievement Standards to the General Assessment

    Science.gov (United States)

    Lazarus, Sheryl S.; Rieke, Rebekah

    2013-01-01

    Schools are facing many changes in the ways that teaching, learning, and assessment take place. Most states are moving from individual state standards to the new Common Core State Standards, which will be fewer, higher, and more rigorous than most current state standards. As the next generation of assessments used for accountability are rolled…

  4. Collateral benefits and hidden hazards of soil arsenic during abatement assessment of residential lead hazards

    International Nuclear Information System (INIS)

    Elless, M.P.; Ferguson, B.W.; Bray, C.A.; Patch, S.; Mielke, H.; Blaylock, M.J.

    2008-01-01

    Abatement of soil-lead hazards may also reduce human exposure to other soil toxins, thereby achieving significant collateral benefits that are not accounted for today. This proposition was tested with the specific case of soil-arsenic, where 1726 residential soil samples were collected and analyzed for lead and arsenic. The study found that these two toxins coexisted in most samples, but their concentrations were weakly correlated, reflecting the differing sources for each toxin. Collateral benefits of 9% would be achieved during abatement of the lead-contaminated soils having elevated arsenic concentrations. However, a hidden hazard of 16% was observed by overlooking elevated arsenic concentrations in soils having lead concentrations not requiring abatement. This study recommends that soil samples collected under HUD programs should be collected from areas of lead and arsenic deposition and tested for arsenic as well as lead, and that soil abatement decisions consider soil-arsenic as well as soil-lead guidelines. - Coexistence of arsenic at elevated concentrations with lead in residential soils undergoing lead hazard assessment is often overlooked, providing either collateral benefits or hidden hazards

  5. Risk assessment of the presence of lead in hunted wild boar meat

    OpenAIRE

    National Committee for Food Safety

    2017-01-01

    Italian National Committee for Food Safety (CNSA) opinion No. 18 of 8 marzo 2017 on the Risk assessment of the presence of lead in hunted wild boar meat Wild game meat may have a higher content in lead than farmed animal meat, both due to the living and dietary habits of such animals and, especially, to the use of lead-based ammunition. The impact of wild game meat on the overall exposure of general consumers is negligible. However, the category of hunters eating meat of wild game sho...

  6. Economic assessment of wild bird mortality induced by the use of lead gunshot in European wetlands.

    Science.gov (United States)

    Andreotti, Alessandro; Guberti, Vittorio; Nardelli, Riccardo; Pirrello, Simone; Serra, Lorenzo; Volponi, Stefano; Green, Rhys E

    2018-01-01

    In European wetlands, at least 40 bird species are exposed to the risk of lead poisoning caused by ingestion of spent lead gunshot. Adopting a methodology developed in North America, we estimated that about 700,000 individuals of 16 waterbird species die annually in the European Union (EU) (6.1% of the wintering population) and one million in whole Europe (7.0%) due to acute effects of lead poisoning. Furthermore, threefold more birds suffer sub-lethal effects. We assessed the economic loss due to this lead-induced mortality of these 16 species by calculating the costs of replacing lethally poisoned wild birds by releasing captive-bred ones. We assessed the cost of buying captive-bred waterbirds for release from market surveys and calculated how many captive-bred birds would have to be released to compensate for the loss, taking into account the high mortality rate of captive birds (72.7%) in the months following release into the wild. Following this approach, the annual cost of waterbird mortality induced by lead shot ingestion is estimated at 105 million euros per year in the EU countries and 142 million euros in the whole of Europe. An alternative method, based upon lost opportunities for hunting caused by deaths due to lead poisoning, gave similar results of 129 million euros per year in the EU countries and 185 million euros per year in the whole of Europe. For several reasons these figures should be regarded as conservative. Inclusion of deaths of species for which there were insufficient data and delayed deaths caused indirectly by lead poisoning and effects on reproduction would probably increase the estimated losses substantially. Nevertheless, our results suggest that the benefits of a restriction on the use of lead gunshot over wetlands could exceed the cost of adapting to non-lead ammunition. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. The impact of product configurators on lead times in engineering-oriented companies

    DEFF Research Database (Denmark)

    Haug, Anders; Hvam, Lars; Mortensen, Niels Henrik

    2011-01-01

    This paper presents a study of how the use of product configurators affects business processes of engineering-oriented companies. A literature study shows that only a minor part of product configuration research deals with the effects of product configuration, and that the ones that do are mostly...... vague when reporting the effects of configurator projects. Only six cases were identified, which provide estimates of the actual size of lead time reduction achieved from product configurators. To broaden this knowledge, this paper presents the results of a study of 14 companies concerning the impact...

  8. Assessment of the bacterial organisms in water from a lead-zinc ...

    African Journals Online (AJOL)

    Twenty-four (24) bulk water samples collected from a lead-zinc mining pit in Ishiagu, Ebonyi State, Nigeria over a period of 2 years were used to assess the bacterial population of the mining pit water. Nine bacterial organisms, which included Bacillus sp., Pseudomonas aeruginosa, Proteus sp., Escherichia coli, ...

  9. Using Diagnostic Assessment to Help Teachers Understand the Chemistry of the Lead-Acid Battery

    Science.gov (United States)

    Cheung, Derek

    2011-01-01

    Nineteen pre-service and in-service teachers taking a chemistry teaching methods course at a university in Hong Kong were asked to take a diagnostic assessment. It consisted of seven multiple-choice questions about the chemistry of the lead-acid battery. Analysis of the teachers' responses to the questions indicated that they had difficulty in…

  10. Human health risk assessment of lead from mining activities at semi-arid locations in the context of total lead exposure.

    Science.gov (United States)

    Zheng, Jiajia; Huynh, Trang; Gasparon, Massimo; Ng, Jack; Noller, Barry

    2013-12-01

    Lead from historical mining and mineral processing activities may pose potential human health risks if materials with high concentrations of bioavailable lead minerals are released to the environment. Since the Joint Expert Committee on Food Additives of Food and Agriculture Organization/World Health Organization withdrew the Provisional Tolerable Weekly Intake of lead in 2011, an alternative method was required for lead exposure assessment. This study evaluated the potential lead hazard to young children (0-7 years) from a historical mining location at a semi-arid area using the U.S. EPA Integrated Exposure Uptake Biokinetic (IEUBK) Model, with selected site-specific input data. This study assessed lead exposure via the inhalation pathway for children living in a location affected by lead mining activities and with specific reference to semi-arid conditions and made comparison with the ingestion pathway by using the physiologically based extraction test for gastro-intestinal simulation. Sensitivity analysis for major IEUBK input parameters was conducted. Three groups of input parameters were classified according to the results of predicted blood concentrations. The modelled lead absorption attributed to the inhalation route was lower than 2 % (mean ± SE, 0.9 % ± 0.1 %) of all lead intake routes and was demonstrated as a less significant exposure pathway to children's blood, compared with ingestion. Whilst dermal exposure was negligible, diet and ingestion of soil and dust were the dominant parameters in terms of children's blood lead prediction. The exposure assessment identified the changing role of dietary intake when house lead loadings varied. Recommendations were also made to conduct comprehensive site-specific human health risk assessment in future studies of lead exposure under a semi-arid climate.

  11. Seismic assessment of a site using the time series method

    International Nuclear Information System (INIS)

    Krutzik, N.J.; Rotaru, I.; Bobei, M.; Mingiuc, C.; Serban, V.; Androne, M.

    2001-01-01

    1. To increase the safety of a NPP located on a seismic site, the seismic acceleration level to which the NPP should be qualified must be as representative as possible for that site, with a conservative degree of safety but not too exaggerated. 2. The consideration of the seismic events affecting the site as independent events and the use of statistic methods to define some safety levels with very low annual occurrence probabilities (10 -4 ) may lead to some exaggerations of the seismic safety level. 3. The use of some very high values for the seismic accelerations imposed by the seismic safety levels required by the hazard analysis may lead to very expensive technical solutions that can make the plant operation more difficult and increase the maintenance costs. 4. The consideration of seismic events as a time series with dependence among the events produced may lead to a more representative assessment of a NPP site seismic activity and consequently to a prognosis on the seismic level values to which the NPP would be ensured throughout its life-span. That prognosis should consider the actual seismic activity (including small earthquakes in real time) of the focuses that affect the plant site. The method is useful for two purposes: a) research, i.e. homogenizing the history data basis by the generation of earthquakes during periods lacking information and correlation of the information with the existing information. The aim is to perform the hazard analysis using a homogeneous data set in order to determine the seismic design data for a site; b) operation, i.e. the performance of a prognosis on the seismic activity on a certain site and consideration of preventive measures to minimize the possible effects of an earthquake. 5. The paper proposes the application of Autoregressive Time Series to issue a prognosis on the seismic activity of a focus and presents the analysis on Vrancea focus that affects Cernavoda NPP site by this method. 6. The paper also presents the

  12. Time Domain View of Liquid-like Screening and Large Polaron Formation in Lead Halide Perovskites

    Science.gov (United States)

    Joshi, Prakriti Pradhan; Miyata, Kiyoshi; Trinh, M. Tuan; Zhu, Xiaoyang

    The structural softness and dynamic disorder of lead halide perovskites contributes to their remarkable optoelectronic properties through efficient charge screening and large polaron formation. Here we provide a direct time-domain view of the liquid-like structural dynamics and polaron formation in single crystal CH3NH3PbBr3 and CsPbBr3 using femtosecond optical Kerr effect spectroscopy in conjunction with transient reflectance spectroscopy. We investigate structural dynamics as function of pump energy, which enables us to examine the dynamics in the absence and presence of charge carriers. In the absence of charge carriers, structural dynamics are dominated by over-damped picosecond motions of the inorganic PbBr3- sub-lattice and these motions are strongly coupled to band-gap electronic transitions. Carrier injection from across-gap optical excitation triggers additional 0.26 ps dynamics in CH3NH3PbBr3 that can be attributed to the formation of large polarons. In comparison, large polaron formation is slower in CsPbBr3 with a time constant of 0.6 ps. We discuss how such dynamic screening protects charge carriers in lead halide perovskites. US Department of Energy, Office of Science - Basic Energy Sciences.

  13. Assessment of the Amount of Hepatohistopatological and Enzymatic Changes after Chronic Lead Intoxication In Utero and Throughout Life in Rat

    Directory of Open Access Journals (Sweden)

    Ronak Mohammadi

    2013-03-01

    Full Text Available Background and Objectives: In order to evaluate the functional changes of liver after lead intoxication, activity of enzymes, including alanine aminotransferase (ALT, aspartate aminotransferase (AST, and alkaline phosphatase (ALP, as well as pathological changes of the liver were assessed in the present study.Methods: Male and female Albino Rats (40 in total in five 8-rat groups were exposed to 0, 5, 10, 15, and 40mg lead acetate dissolved in 1 liter drinking water, from the onset of embryonic life to 16th week of life. At the end of 16th week, the animals were anesthetized with chloroform, and blood sampling from heart was performed. After serum separation for biochemical analysis, liver was taken out and fixed in 15% formalin for histopathological studies. Activity of ALT, AST, and ALP, as well as lead concentration of the serum samples were measured using spectrophotometrical method and graphite furnace atomic absorption, respectively. The tissue sections were histologically studied under light microscopy after staining by hematoxylin/eosin. The results were analyzed using analysis of variance and Tukey's test, and p<0.05 was considered significant.Results: In this study, liver enzymes activities had direct relation with the serum lead concentration, and showed a significant increase compared to the control groups. Histological changes were observed as inflammation, lymphocyte infiltration to liver tissue, and liver cells necrosis.Conclusion: According to the results of this study, long-time exposure to lead results in dose- and time-dependent liver injury.

  14. Optimization and Customer Utilities under Dynamic Lead Time Quotation in an M/M Type Base Stock System

    Directory of Open Access Journals (Sweden)

    Koichi Nakade

    2017-01-01

    Full Text Available In a manufacturing and inventory system, information on production and order lead time helps consumers’ decision whether they receive finished products or not by considering their own impatience on waiting time. In Savaşaneril et al. (2010, the optimal dynamic lead time quotation policy in a one-stage production and inventory system with a base stock policy for maximizing the system’s profit and its properties are discussed. In this system, each arriving customer decides whether he/she enters the system based on the quoted lead time informed by the system. On the other hand, the customer’s utility may be small under the optimal quoted lead time policy because the actual lead time may be longer than the quoted lead time. We use a utility function with respect to benefit of receiving products and waiting time and propose several kinds of heuristic lead time quotation policies. These are compared with optimal policies with respect to both profits and customer’s utilities. Through numerical examples some kinds of heuristic policies have better expected utilities of customers than the optimal quoted lead time policy maximizing system’s profits.

  15. Neutron CT with a multi-detector system leading to drastical reduction of the measuring time

    International Nuclear Information System (INIS)

    Hehn, G.; Pfister, G.; Schatz, A.; Goebel, J.; Kofler, R.

    1993-09-01

    By means of numerical simulation methods and their verification with measurements it could be shown that such a detector system can be realized for a line beam and 1-2 detectors per cm. With the maximum available beam width of the fast neutron field at the FRM approximately 20 detectors can be used leading to a reduction of the measuring time to 0,5 - 1 hour. A multi detector system for a line beam of thermal neutrons was constructed, tested and used for CT-measurements. This detector system for the measurement of thinner layers with better spatial resolution could be realized. The electronic discrimination between neutrons and gamma rays has been improved. This discrimination was used in all CT-measurements to get transmission values of both kinds of radiation and to reconstruct to complementary CT-images. The use of a polyenergetic radiation causes spectral shifts in the transmission spectrum leading to artifacts in the reconstructed CT-image. The transmission values must be spectral corrected before image reconstruction, because the image artifacts complicate the image evaluation or make it impossible. A new energy selective procedure for the online spectral correction was developed. This method is based on the concept to measure additionally to the integral transmission value his pulse height spectrum and to do the correction depending on the changes in this pulse height spectrum. (orig./HP) [de

  16. Modularity, Lead time and Return Policy for Supply Chain in Mass Customization System

    Directory of Open Access Journals (Sweden)

    Jizi Li

    2016-12-01

    Full Text Available Mass Customization (MC is a flexible manufacturing system with features of Mass Production (MP and Customization Production (CP. However, there is few researches about competition aamp; cooperation between the upstream MP firm (module manufacturer and downstream CP firm (assembler under MC supply chain scenario. From supply chain perspective, this paper first develops the base models considering the influences of return policy, modularity level, production lead time and pricing factors. Furthermore, according to the different decision-making situations, three kinds of MC supply chain models in competitive or cooperative environment (i.e. simultaneous-move game, sequential-move game and the cooperative game have been built, then, the optimal solution of each model have been analyzed and compared, and coordination mechanism is design to cooperate in MC supply chain via profit-sharing with Nash bargaining power. Finally, through the numerical analysis, we find the highest profit is from the cooperative setting, then followed by in simultaneous-move and sequential-move one, the reason is that the lowest product price and the largest market demand easily occurs in the cooperative game compared with the others, the upstream module manufacturer takes advantage of MP to increase the modularity level and decrease manufacturing cost for the whole supply chain, the downstream assembler task is to shorten the lead time according to customerarsquo;s needs, while the wholesale price in cooperative game higher than simultaneous-move game and sequential-move game can ensure each firmarsquo;s benefits, effectively prevent from the effect of double marginalization and obtain Pareto optimality.

  17. Are Lead Exposures a Risk in European Fresh Waters? A Regulatory Assessment Accounting for Bioavailability.

    Science.gov (United States)

    Peters, Adam; Wilson, Iain; Merrington, Graham; Chowdhury, M Jasim

    2018-01-01

    An indicative compliance assessment of the Europe-wide bioavailable lead Environmental Quality Standard of 1.2 µg L -1 (EQS) was undertaken against regulatory freshwater monitoring data from six European member states and FOREGS database. Bio-met, a user-friendly tool based upon Biotic Ligand Models (BLMs) was used to account for bioavailability, along with the current European Water Framework Directive lead dissolved organic carbon correction approach. The outputs from both approaches were compared to the BLM. Of the 9054 freshwater samples assessed only 0.6% exceeded the EQS of 1.2 µg L -1 after accounting for bioavailability. The data showed that ambient background concentrations of lead across Europe are unlikely to influence general compliance with the EQS, although there may be isolated local issues. The waters showing the greatest sensitivity to potential lead exposures are characterized by relatively low DOC (< 0.5 mg L -1 ), regardless of the pH and calcium concentrations.

  18. Note: Optimal base-stock policy for the inventory system with periodic review, backorders and sequential lead times

    DEFF Research Database (Denmark)

    Johansen, Søren Glud; Thorstenson, Anders

    We show that well-known textbook formulae for determining the optimal base stock of the inventory system with continuous review and constant lead time can easily be extended to the case with periodic review and stochastic, sequential lead times. The provided performance measures and conditions...

  19. The Environmental Burdens of Lead-Acid Batteries in China: Insights from an Integrated Material Flow Analysis and Life Cycle Assessment of Lead

    Directory of Open Access Journals (Sweden)

    Sha Chen

    2017-11-01

    Full Text Available Lead-acid batteries (LABs, a widely used energy storage equipment in cars and electric vehicles, are becoming serious problems due to their high environmental impact. In this study, an integrated method, combining material flow analysis with life cycle assessment, was developed to analyze the environmental emissions and burdens of lead in LABs. The environmental burdens from other materials in LABs were not included. The results indicated that the amount of primary lead used in LABs accounted for 77% of the total lead production in 2014 in China. The amount of discharged lead into the environment was 8.54 × 105 tonnes, which was mainly from raw material extraction (57.2%. The largest environmental burden was from the raw materials extraction and processing, which accounted for 81.7% of the total environmental burdens. The environmental burdens of the environmental toxicity potential, human toxicity potential-cancer, human toxicity potential-non-cancer, water footprint and land use accounted for more than 90% at this stage. Moreover, the environmental burdens from primary lead was much more serious than regenerated lead. On the basis of the results, main practical measures and policies were proposed to reduce the lead emissions and environmental burdens of LABs in China, namely establishing an effective LABs recycling system, enlarging the market share of the legal regenerated lead, regulating the production of regenerated lead, and avoiding the long-distance transportation of the waste LABs.

  20. Comparison of Inventory Systems with Service, Positive Lead-Time, Loss, and Retrial of Customers

    Directory of Open Access Journals (Sweden)

    A. Krishnamoorthy

    2007-01-01

    Full Text Available We analyze and compare three (s,S inventory systems with positive service time and retrial of customers. In all of these systems, arrivals of customers form a Poisson process and service times are exponentially distributed. When the inventory level depletes to s due to services, an order of replenishment is placed. The lead-time follows an exponential distribution. In model I, an arriving customer, finding the inventory dry or server busy, proceeds to an orbit with probability γ and is lost forever with probability (1−γ. A retrial customer in the orbit, finding the inventory dry or server busy, returns to the orbit with probability δ and is lost forever with probability (1−δ. In addition to the description in model I, we provide a buffer of varying (finite capacity equal to the current inventory level for model II and another having capacity equal to the maximum inventory level S for model III. In models II and III, an arriving customer, finding the buffer full, proceeds to an orbit with probability γ and is lost forever with probability (1−γ. A retrial customer in the orbit, finding the buffer full, returns to the orbit with probability δ and is lost forever with probability (1−δ. In all these models, the interretrial times are exponentially distributed with linear rate. Using matrix-analytic method, we study these inventory models. Some measures of the system performance in the steady state are derived. A suitable cost function is defined for all three cases and analyzed using graphical illustrations.

  1. Great Physicists - The Life and Times of Leading Physicists from Galileo to Hawking

    International Nuclear Information System (INIS)

    Cropper, William H

    2002-01-01

    The author, a former American chemistry professor, has organized his book into nine parts with 29 chapters, covering, in a fairly historical sequence and systematic conceptual progression, all fundamentals of today's physics: i.e., mechanics, thermodynamics, electromagnetism, statistical mechanics, relativity, quantum mechanics, nuclear physics, particle physics, astronomy-astrophysics-cosmology. Obviously, the 20th century (when about 90% of professional physicists of all time worked) assumes with five topics the dominant role in this enterprise. For each topic, a small number (ranging from one to eight) of leading personalities is selected and the biographies of these 29 physicists, including two women (Marie Curie and Lise Meitner), are presented in some detail together with their achievements in the particular topic. Important relevant contributions of other scholars to each topic are also discussed. In addition, Cropper provides each of the topics with a short 'historical synopsis' justifying his selection of key persons. One may argue that concentrating on leading physicists constitutes an old-fashioned approach to displaying the history and contents of fundamental topics in physics. However, the mixture of biographies and explanation of leading contributions given here will certainly serve for a larger public, not just professional physicists and scientists, as a guide through the exciting development of physical ideas and discoveries. In general, the presentation of the material is quite satisfactory (with only few slips, e.g., in the Meitner story, where the author follows too closely a new biography) and gives the essence of the great advances in physics since the 15th century. One notices perhaps the limitation of the author in cases where no biography in English is available - this would also explain the omission of some of the main contributors to atomic and particle physics, such as Arnold Sommerfeld and Hideki Yukawa, or that French or Russian

  2. BOOK REVIEW: Great Physicists - The Life and Times of Leading Physicists from Galileo to Hawking

    Science.gov (United States)

    Cropper, William H.

    2002-11-01

    The author, a former American chemistry professor, has organized his book into nine parts with 29 chapters, covering, in a fairly historical sequence and systemtic conceptual progression, all fundamentals of today's physics: i.e., mechanics, thermodynamics, electromagnetism, statistical mechanics, relativity, quantum mechanics, nuclear physics, particle physics, astronomy-astrophysics-cosmology. Obviously, the 20th century (when about 90% of professional physicists of all time worked) assumes with five topics the dominant role in this enterprise. For each topic, a small number (ranging from one to eight) of leading personalities is selected and the biographies of these 29 physicists, including two women (Marie Curie and Lise Meitner), are presented in some detail together with their achievements in the particular topic. Important relevant contributions of other scholars to each topic are also discussed. In addition, Cropper provides each of the topics with a short 'historical synopsis' justifying his selection of key persons. One may argue that concentrating on leading physicists constitutes an old-fashioned approach to displaying the history and contents of fundamental topics in physics. However, the mixture of biographies and explanation of leading contributions given here will certainly serve for a larger public, not just professional physicists and scientists, as a guide through the exciting development of physical ideas and discoveries. In general, the presentation of the material is quite satisfactory (with only few slips, e.g., in the Meitner story, where the author follows too closely a new biography) and gives the essence of the great advances in physics since the 15th century. One notices perhaps the limitation of the author in cases where no biography in English is available - this would also explain the omission of some of the main contributors to atomic and particle physics, such as Arnold Sommerfeld and Hideki Yukawa, or that French or Russian readers

  3. Identification of appropriate lags and temporal resolutions for low flow indicators in the River Rhine to forecast low flows with different lead times

    NARCIS (Netherlands)

    Demirel, M.C.; Booij, Martijn J.; Hoekstra, Arjen Ysbert

    2013-01-01

    The aim of this paper is to assess the relative importance of low flow indicators for the River Rhine and to identify their appropriate temporal lag and resolution. This is done in the context of low flow forecasting with lead times of 14 and 90 days. First, the Rhine basin is subdivided into seven

  4. Routine lead isotope determinations using a lead-207-lead-204 double spike: a long-term assessment of analytical precision and accuracy

    International Nuclear Information System (INIS)

    Woodhead, J.D.; McCulloch, M.T.; Volker, F.

    1995-01-01

    Lead-isotope data obtained on a multicollector mass spectrometer over a four year period using a 207 Pb- 204 Pb double spike to correct for the effects of mass discrimination, are reported. Considerable improvements in both precision and accuracy over conventional correction procedures were noted, without recourse to rigorous loading or run conditions. An external precision in 206 Pb/ 204 Pb, 207 Pb/ 204 Pb and 208 Pb/ 204 Pb ratios ± 0.003, 0.003 and 0.01 (2 x standard deviation), respectively, is routinely obtainable independent of minor variations in loading and run parameters. (author)

  5. Extracting Leading Nonlinear Modes of Changing Climate From Global SST Time Series

    Science.gov (United States)

    Mukhin, D.; Gavrilov, A.; Loskutov, E. M.; Feigin, A. M.; Kurths, J.

    2017-12-01

    Data-driven modeling of climate requires adequate principal variables extracted from observed high-dimensional data. For constructing such variables it is needed to find spatial-temporal patterns explaining a substantial part of the variability and comprising all dynamically related time series from the data. The difficulties of this task rise from the nonlinearity and non-stationarity of the climate dynamical system. The nonlinearity leads to insufficiency of linear methods of data decomposition for separating different processes entangled in the observed time series. On the other hand, various forcings, both anthropogenic and natural, make the dynamics non-stationary, and we should be able to describe the response of the system to such forcings in order to separate the modes explaining the internal variability. The method we present is aimed to overcome both these problems. The method is based on the Nonlinear Dynamical Mode (NDM) decomposition [1,2], but takes into account external forcing signals. An each mode depends on hidden, unknown a priori, time series which, together with external forcing time series, are mapped onto data space. Finding both the hidden signals and the mapping allows us to study the evolution of the modes' structure in changing external conditions and to compare the roles of the internal variability and forcing in the observed behavior. The method is used for extracting of the principal modes of SST variability on inter-annual and multidecadal time scales accounting the external forcings such as CO2, variations of the solar activity and volcanic activity. The structure of the revealed teleconnection patterns as well as their forecast under different CO2 emission scenarios are discussed.[1] Mukhin, D., Gavrilov, A., Feigin, A., Loskutov, E., & Kurths, J. (2015). Principal nonlinear dynamical modes of climate variability. Scientific Reports, 5, 15510. [2] Gavrilov, A., Mukhin, D., Loskutov, E., Volodin, E., Feigin, A., & Kurths, J. (2016

  6. Geostatistical analyses and hazard assessment on soil lead in Silvermines area, Ireland

    International Nuclear Information System (INIS)

    McGrath, David; Zhang Chaosheng; Carton, Owen T.

    2004-01-01

    Spatial distribution and hazard assessment of soil lead in the mining site of Silvermines, Ireland, were investigated using statistics, geostatistics and geographic information system (GIS) techniques. Positively skewed distribution and possible outlying values of Pb and other heavy metals were observed. Box-Cox transformation was applied in order to achieve normality in the data set and to reduce the effect of outliers. Geostatistical analyses were carried out, including calculation of experimental variograms and model fitting. The ordinary point kriging estimates of Pb concentration were mapped. Kriging standard deviations were regarded as the standard deviations of the interpolated pixel values, and a second map was produced, that quantified the probability of Pb concentration higher than a threshold value of 1000 mg/kg. These maps provide valuable information for hazard assessment and for decision support. - A probability map was produced that was useful for hazard assessment and decision support

  7. Geostatistical analyses and hazard assessment on soil lead in Silvermines area, Ireland

    Energy Technology Data Exchange (ETDEWEB)

    McGrath, David; Zhang Chaosheng; Carton, Owen T

    2004-01-01

    Spatial distribution and hazard assessment of soil lead in the mining site of Silvermines, Ireland, were investigated using statistics, geostatistics and geographic information system (GIS) techniques. Positively skewed distribution and possible outlying values of Pb and other heavy metals were observed. Box-Cox transformation was applied in order to achieve normality in the data set and to reduce the effect of outliers. Geostatistical analyses were carried out, including calculation of experimental variograms and model fitting. The ordinary point kriging estimates of Pb concentration were mapped. Kriging standard deviations were regarded as the standard deviations of the interpolated pixel values, and a second map was produced, that quantified the probability of Pb concentration higher than a threshold value of 1000 mg/kg. These maps provide valuable information for hazard assessment and for decision support. - A probability map was produced that was useful for hazard assessment and decision support.

  8. Assessment of the pollution and ecological risk of lead and cadmium in soils.

    Science.gov (United States)

    Wieczorek, Jerzy; Baran, Agnieszka; Urbański, Krzysztof; Mazurek, Ryszard; Klimowicz-Pawlas, Agnieszka

    2018-03-27

    The aim of the study was to assess the content, distribution, soil binding capacity, and ecological risk of cadmium and lead in the soils of Malopolska (South Poland). The investigation of 320 soil samples from differently used land (grassland, arable land, forest, wasteland) revealed a very high variation in the metal content in the soils. The pollution of soils with cadmium and lead is moderate. Generally, a point source of lead and cadmium pollution was noted in the study area. The highest content of cadmium and lead was found in the northwestern part of the area-the industrial zones (mining and metallurgical activity). These findings are confirmed by the arrangement of semivariogram surfaces and bivariate Moran's correlation coefficients. Among the different types of land use, forest soils had by far the highest mean content of bioavailable forms of both metals. The results showed a higher soil binding capacity for lead than for cadmium. However, for both metals, extremely high (class 5) accumulation capacities were dominant. Based on the results, the investigated soils had a low (Pb) and moderate (Cd) ecological risk on living components. Soil properties, such as organic C, pH, sand, silt, and clay content, correlated with the content of total and bioavailable forms of metals in the soils. The correlations, despite being statistically significant, were characterized by very low values of correlation coefficient (r = 0.12-0.20, at p ≤ 0.05). Therefore, the obtained data do not allow to define any conclusions as to the relationships between these soil properties. However, it must be highlighted that there was a very strong positive correlation between the total content of cadmium and lead and their bioavailable forms in the soils.

  9. Assessment of the Efficacy of Chelate-Assisted Phytoextraction of Lead by Coffeeweed (Sesbania exaltata Raf.

    Directory of Open Access Journals (Sweden)

    Gloria Miller

    2008-12-01

    Full Text Available Lead (Pb, depending upon the reactant surface, pH, redox potential and other factors can bind tightly to the soil with a retention time of many centuries. Soil-metal interactions by sorption, precipitation and complexation processes, and differences between plant species in metal uptake efficiency, transport, and susceptibility make a general prediction of soil metal bioavailability and risks of plant metal toxicity difficult. Moreover, the tight binding characteristic of Pb to soils and plant materials make a significant portion of Pb unavailable for uptake by plants. This experiment was conducted to determine whether the addition of ethylenediaminetetraacetic acid (EDTA, ethylene glycol tetraacetic acid (EGTA, or acetic acid (HAc can enhance the phytoextraction of Pb by making the Pb soluble and more bioavailable for uptake by coffeeweed (Sesbania exaltata Raf.. Also we wanted to assess the efficacy of chelates in facilitating translocation of the metal into the above-ground biomass of this plant. To test the effect of chelates on Pb solubility, 2 g of Pb-spiked soil (1000 mg Pb/kg dry soil were added to each 15 mL centrifuge tube. Chelates (EDTA, EGTA, HAc in a 1:1 ratio with the metal, or distilled deionized water were then added. Samples were shaken on a platform shaker then centrifuged at the end of several time periods. Supernatants were filtered with a 0.45 μm filter and quantified by inductively coupled plasma-optical emission spectrometry (ICP-OES to determine soluble Pb concentrations. Results revealed that EDTA was the most effective in bringing Pb into solution, and that maximum solubility was reached 6 days after chelate amendment. Additionally, a greenhouse experiment was conducted by planting Sesbania seeds in plastic tubes containing top soil and peat (2:1, v:v spiked with various levels (0, 1000, 2000 mg Pb/kg dry soil of lead nitrate. At six weeks after emergence, aqueous solutions of EDTA and/or HAc (in a 1:1 ratio

  10. Quantifying lead-time bias in risk factor studies of cancer through simulation.

    Science.gov (United States)

    Jansen, Rick J; Alexander, Bruce H; Anderson, Kristin E; Church, Timothy R

    2013-11-01

    Lead-time is inherent in early detection and creates bias in observational studies of screening efficacy, but its potential to bias effect estimates in risk factor studies is not always recognized. We describe a form of this bias that conventional analyses cannot address and develop a model to quantify it. Surveillance Epidemiology and End Results (SEER) data form the basis for estimates of age-specific preclinical incidence, and log-normal distributions describe the preclinical duration distribution. Simulations assume a joint null hypothesis of no effect of either the risk factor or screening on the preclinical incidence of cancer, and then quantify the bias as the risk-factor odds ratio (OR) from this null study. This bias can be used as a factor to adjust observed OR in the actual study. For this particular study design, as average preclinical duration increased, the bias in the total-physical activity OR monotonically increased from 1% to 22% above the null, but the smoking OR monotonically decreased from 1% above the null to 5% below the null. The finding of nontrivial bias in fixed risk-factor effect estimates demonstrates the importance of quantitatively evaluating it in susceptible studies. Copyright © 2013 Elsevier Inc. All rights reserved.

  11. Leaching assessment of road materials containing primary lead and zinc slags.

    Science.gov (United States)

    Barna, R; Moszkowicz, P; Gervais, C

    2004-01-01

    Characterisation of the leaching behaviour of waste-containing materials is a crucial step in the environmental assessment for reuse scenarios. In our research we applied the multi-step European methodology ENV 12-920 to the leaching assessment of road materials containing metallurgical slag. A Zn slag from an imperial smelting furnace (ISF) and a Pb slag from a lead blast furnace (LBF) are investigated. The two slags contain up to 11.2 wt% of lead and 3.5 wt% of zinc and were introduced as a partial substitute for sand in two road materials, namely sand-cement and sand-bitumen. At the laboratory scale, a leaching assessment was performed first through batch equilibrium leaching tests. Second, the release rate of the contaminants was evaluated using saturated leaching tests on monolithic material. Third, laboratory tests were conducted on monolithic samples under intermittent wetting conditions. Pilot-scale tests were conducted for field testing of intermittent wetting conditions. The results show that the release of Pb and Zn from the materials in a saturated scenario was controlled by the pH of the leachates. For the intermittent wetting conditions, an additional factor, blocking of the pores by precipitation during the drying phase is proposed. Pilot-scale leaching behaviour only partially matched with the laboratory-scale test results: new mass transfer mechanisms and adapted laboratory leaching tests are discussed.

  12. Health Assessment of Heavy Metal Pollution (Cadmium, Lead, Arsenic in Citrus Marketed in Tehran, Iran, 2015

    Directory of Open Access Journals (Sweden)

    Razieh Saleh

    2017-03-01

    Full Text Available Background & Aims of the Study: Today, the environment pollution with heavy metals has increased. It is important to study various types of pollutions specially those regarding fruits. The effect of pollutions on food safety for human consumption is a global concern.  This study was conducted for health assessment of heavy metals pollution (cadmium, lead, and arsenic in citrus marketed in Tehran, Iran in 2015. Materials & Methods: After collecting and preparing 2 samples from each citrus species (tangerine, grapefruit, sweet lime, sour orange, orange with acid digestion method, the citrus pulp and peel were surveyed. Inductively coupled plasma optical emission spectrometry (ICP-OES was used to determine the concentrations of heavy metals with three replications. Moreover, SPSS version 19 was employed to perform statistical analysis. Results: The results showed that the concentration average of Cadmium, Lead and Arsenic in citrus samples of the pulp parts were 19.73, 42.95 and 2.30 mg/kg and in peel parts were 20.09, 42.71 and 2.12 mg/kg, respectively. The average concentrations of heavy metals were higher than WHO maximum permissible limits. Conclusions: Based on these results, consumption of citrus species has no adverse effect on the consumers’ health (except Sweet lime, Orange, Tangerine and Grapefruit in lead is risky for adults and Sweet lime and Orange that Health Index in Lead and Arsenic and Sour Orange, Tangerine and Grapefruit that Health Index in Lead is more than 1 and is risky for children. Thus, individuals living in Tehran should be cautious about using these citrus fruits and researchers should try to obtain national standards in the field of entering these metals to food in environmental conditions that are in Iran.

  13. Leading safety performance indicators for resilience assessment of radiopharmaceuticals production process

    Energy Technology Data Exchange (ETDEWEB)

    Grecco, Claudio H.S.; Santos, Isaac J.A.L.; Carvalho, Paulo V.R., E-mail: grecco@ien.gov.b, E-mail: luquetti@ien.gov.b, E-mail: paulov@ien.gov.b [Instituto de Engenharia Nuclear (IEN/CNEN-RJ), Rio de Janeiro, RJ (Brazil). Div. de Instrumentacao e Confiabilidade Humana; Vidal, Mario C.R., E-mail: mvidal@ergonomia.ufrj.b [Coordenacao dos Programas de Pos-Graduacao de Engenharia (PEP/COPPE/UFRJ), Rio de Janeiro, RJ (Brazil). Programa de Engenharia de Producao. Grupo de Ergonomia e Novas Tecnologias (GENTE)

    2011-07-01

    Radiopharmaceuticals are radiation-emitting substances used in medicine for radiotherapy and imaging diagnosis. A Research Institute, located in Rio de Janeiro, produces three radiopharmaceuticals: the sodium iodate is used in the diagnosis of thyroid dysfunctions, the meta-iodo-benzyl guanidine is used in the diagnosis of cardiac diseases, and the fluorodeoxyglucose is used in diagnosis in cardiology, oncology, neurology and neuro psychiatry. This paper presents a leading safety performance indicators framework to assess the resilience of radiopharmaceuticals production processes. The organizations that use resilience indicators will be able to pro actively evaluate and manage safety. (author)

  14. Leading safety performance indicators for resilience assessment of radiopharmaceuticals production process

    International Nuclear Information System (INIS)

    Grecco, Claudio H.S.; Santos, Isaac J.A.L.; Carvalho, Paulo V.R.

    2011-01-01

    Radiopharmaceuticals are radiation-emitting substances used in medicine for radiotherapy and imaging diagnosis. A Research Institute, located in Rio de Janeiro, produces three radiopharmaceuticals: the sodium iodate is used in the diagnosis of thyroid dysfunctions, the meta-iodo-benzyl guanidine is used in the diagnosis of cardiac diseases, and the fluorodeoxyglucose is used in diagnosis in cardiology, oncology, neurology and neuro psychiatry. This paper presents a leading safety performance indicators framework to assess the resilience of radiopharmaceuticals production processes. The organizations that use resilience indicators will be able to pro actively evaluate and manage safety. (author)

  15. Performance assessment of static lead-lag feedforward controllers for disturbance rejection in PID control loops.

    Science.gov (United States)

    Yu, Zhenpeng; Wang, Jiandong

    2016-09-01

    This paper assesses the performance of feedforward controllers for disturbance rejection in univariate feedback plus feedforward control loops. The structures of feedback and feedforward controllers are confined to proportional-integral-derivative and static-lead-lag forms, respectively, and the effects of feedback controllers are not considered. The integral squared error (ISE) and total squared variation (TSV) are used as performance metrics. A performance index is formulated by comparing the current ISE and TSV metrics to their own lower bounds as performance benchmarks. A controller performance assessment (CPA) method is proposed to calculate the performance index from measurements. The proposed CPA method resolves two critical limitations in the existing CPA methods, in order to be consistent with industrial scenarios. Numerical and experimental examples illustrate the effectiveness of the obtained results. Copyright © 2016 ISA. Published by Elsevier Ltd. All rights reserved.

  16. Computational procedure of optimal inventory model involving controllable backorder rate and variable lead time with defective units

    Science.gov (United States)

    Lee, Wen-Chuan; Wu, Jong-Wuu; Tsou, Hsin-Hui; Lei, Chia-Ling

    2012-10-01

    This article considers that the number of defective units in an arrival order is a binominal random variable. We derive a modified mixture inventory model with backorders and lost sales, in which the order quantity and lead time are decision variables. In our studies, we also assume that the backorder rate is dependent on the length of lead time through the amount of shortages and let the backorder rate be a control variable. In addition, we assume that the lead time demand follows a mixture of normal distributions, and then relax the assumption about the form of the mixture of distribution functions of the lead time demand and apply the minimax distribution free procedure to solve the problem. Furthermore, we develop an algorithm procedure to obtain the optimal ordering strategy for each case. Finally, three numerical examples are also given to illustrate the results.

  17. Optimal Ordering Policy and Coordination Mechanism of a Supply Chain with Controllable Lead-Time-Dependent Demand Forecast

    Directory of Open Access Journals (Sweden)

    Hua-Ming Song

    2011-01-01

    Full Text Available This paper investigates the ordering decisions and coordination mechanism for a distributed short-life-cycle supply chain. The objective is to maximize the whole supply chain's expected profit and meanwhile make the supply chain participants achieve a Pareto improvement. We treat lead time as a controllable variable, thus the demand forecast is dependent on lead time: the shorter lead time, the better forecast. Moreover, optimal decision-making models for lead time and order quantity are formulated and compared in the decentralized and centralized cases. Besides, a three-parameter contract is proposed to coordinate the supply chain and alleviate the double margin in the decentralized scenario. In addition, based on the analysis of the models, we develop an algorithmic procedure to find the optimal ordering decisions. Finally, a numerical example is also presented to illustrate the results.

  18. Real-Time Salmonella Detection Using Lead Zirconate Titanate-Titanium Microcantilevers

    National Research Council Canada - National Science Library

    McGovern, John-Paul; Shih, Wan Y; Shih, Wei-Heng; Sergi, Mauro; Chaiken, Irwin

    2005-01-01

    .... We have developed and investigated the use of a lead zirconate titanate - titanium (PZT-Ti) microcantilever for in situ detection of the common food- and water-born pathogen, Salmonella typhimurium...

  19. Lead Slowing-Down Spectrometry Time Spectral Analysis for Spent Fuel Assay: FY12 Status Report

    Energy Technology Data Exchange (ETDEWEB)

    Kulisek, Jonathan A.; Anderson, Kevin K.; Casella, Andrew M.; Siciliano, Edward R.; Warren, Glen A.

    2012-09-28

    Executive Summary Developing a method for the accurate, direct, and independent assay of the fissile isotopes in bulk materials (such as used fuel) from next-generation domestic nuclear fuel cycles is a goal of the Office of Nuclear Energy, Fuel Cycle R&D, Material Protection and Control Technology (MPACT) Campaign. To meet this goal, MPACT supports a multi-institutional collaboration, of which PNNL is a part, to study the feasibility of Lead Slowing Down Spectroscopy (LSDS). This technique is an active nondestructive assay method that has the potential to provide independent, direct measurement of Pu and U isotopic masses in used fuel with an uncertainty considerably lower than the approximately 10% typical of today’s confirmatory methods. This document is a progress report for FY2012 PNNL analysis and algorithm development. Progress made by PNNL in FY2012 continues to indicate the promise of LSDS analysis and algorithms applied to used fuel assemblies. PNNL further refined the semi-empirical model developed in FY2011 based on singular value decomposition (SVD) to numerically account for the effects of self-shielding. The average uncertainty in the Pu mass across the NGSI-64 fuel assemblies was shown to be less than 3% using only six calibration assemblies with a 2% uncertainty in the isotopic masses. When calibrated against the six NGSI-64 fuel assemblies, the algorithm was able to determine the total Pu mass within <2% uncertainty for the 27 diversion cases also developed under NGSI. Two purely empirical algorithms were developed that do not require the use of Pu isotopic fission chambers. The semi-empirical and purely empirical algorithms were successfully tested using MCNPX simulations as well applied to experimental data measured by RPI using their LSDS. The algorithms were able to describe the 235U masses of the RPI measurements with an average uncertainty of 2.3%. Analyses were conducted that provided valuable insight with regard to design requirements (e

  20. Examining Progress across Time with Practical Assessments in Ensemble Settings

    Science.gov (United States)

    Crochet, Lorrie S.; Green, Susan K.

    2012-01-01

    This article provides the rationale for effective music assessment that tracks individual progress across time and offers examples to illustrate assessment of a range of music-learning goals. Gauging progress across time helps students become more mastery-oriented, while showing more effort and positive attitudes. As instruction and assessment…

  1. A simple method to assess unsaturated zone time lag in the travel time from ground surface to receptor.

    Science.gov (United States)

    Sousa, Marcelo R; Jones, Jon P; Frind, Emil O; Rudolph, David L

    2013-01-01

    In contaminant travel from ground surface to groundwater receptors, the time taken in travelling through the unsaturated zone is known as the unsaturated zone time lag. Depending on the situation, this time lag may or may not be significant within the context of the overall problem. A method is presented for assessing the importance of the unsaturated zone in the travel time from source to receptor in terms of estimates of both the absolute and the relative advective times. A choice of different techniques for both unsaturated and saturated travel time estimation is provided. This method may be useful for practitioners to decide whether to incorporate unsaturated processes in conceptual and numerical models and can also be used to roughly estimate the total travel time between points near ground surface and a groundwater receptor. This method was applied to a field site located in a glacial aquifer system in Ontario, Canada. Advective travel times were estimated using techniques with different levels of sophistication. The application of the proposed method indicates that the time lag in the unsaturated zone is significant at this field site and should be taken into account. For this case, sophisticated and simplified techniques lead to similar assessments when the same knowledge of the hydraulic conductivity field is assumed. When there is significant uncertainty regarding the hydraulic conductivity, simplified calculations did not lead to a conclusive decision. Copyright © 2012 Elsevier B.V. All rights reserved.

  2. Radiogenic Lead Isotopes and Time Stratigraphy in the Hudson River, New York

    International Nuclear Information System (INIS)

    Chillrud, Steven N.; Bopp, Richard F.; Ross, James M.; Chaky, Damon A.; Hemming, Sidney; Shuster, Edward L.; Simpson, H. James; Estabrooks, Frank

    2004-01-01

    Radionuclide, radiogenic lead isotope and trace metal analyses on fine-grained sediment cores collected along 160 km of the upper and tidal Hudson River were used to examine temporal trends of contaminant loadings and to develop radiogenic lead isotopes both as a stratigraphic tool and as tracers for resolving decadal particle transport fluxes. Very large inputs of Cd, Sb, Pb, and Cr are evident in the sediment record, potentially from a single manufacturing facility. The total range in radiogenic lead isotope ratios observed in well-dated cores collected about 24 km downstream of the plant is large (e.g., maximum difference in 206 Pb/ 207 Pb is 10%), characterized by four major shifts occurring in the 1950s, 1960s, 1970s and 1980s. The upper Hudson signals in Cd and radiogenic lead isotopes were still evident in sediments collected 160 km downstream in the tidal Hudson. The large magnitude and abrupt shifts in radiogenic lead isotope ratios as a function of depth provide sensitive temporal constraints that complement information derived from radionuclide analyses to significantly improve the precision of dating assignments. Application of a simple dilution model to data from paired cores suggests much larger sediment inputs in one section of the river than previously reported, suggesting particle influxes to the Hudson have been underestimated

  3. Using trace element content and lead isotopic composition to assess sources of PM in Tijuana, Mexico

    Science.gov (United States)

    Salcedo, D.; Castro, T.; Bernal, J. P.; Almanza-Veloz, V.; Zavala, M.; González-Castillo, E.; Saavedra, M. I.; Perez-Arvízu, O.; Díaz-Trujillo, G. C.; Molina, L. T.

    2016-05-01

    PM2.5 samples were collected at two urban sites (Parque Morelos (PQM) and CECyTE (CEC)) in Tijuana during the Cal-Mex campaign from May 24 to June 5, 2010. Concentration of trace elements (Mg, Al, Ti, V, Mn, Fe, Co, Ni, Zn, Cu, Ga, As, Se, Rb, Sr, Mo, Cd, Sn, Sb, Ba, La, Ce, and Pb), and Pb isotopic composition were determined in order to study the sources of PM impacting each site. Other chemical analysis (gravimetric, elemental and organic carbon (EC/OC), and polycyclic aromatic hydrocarbons (PAHs)), were also performed. Finally, back-trajectories were calculated to facilitate the interpretation of the chemical data. Trace elements results show that CEC is a receptor site affected by mixed regional sources: sea salt, mineral, urban, and industrial. On the other hand, PQM seems to be impacted mainly by local sources. In particular, Pb at CEC is of anthropogenic, as well as crustal origin. This conclusion is supported by the lead isotopic composition, whose values are consistent with a combination of lead extracted from US mines, and lead from bedrocks in the Mexican Sierras. Some of the time variability observed can be explained using the back-trajectories.

  4. Turbulent Wing-Leading-Edge Correlation Assessment for the Shuttle Orbiter

    Science.gov (United States)

    King, Rudolph A.; Vaughan, Matthew P.

    2009-01-01

    This study was conducted in support of the Orbiter damage assessment activity that takes place for each Shuttle mission since STS-107 (STS - Space Transportation System). As part of the damage assessment activity, the state of boundary layer (laminar or turbulent) during reentry needs to be estimated in order to define the aerothermal environment on the Orbiter. Premature turbulence on the wing leading edge (WLE) is possible if a surface irregularity promotes early transition and the resulting turbulent wedge flow contaminates the WLE flow. The objective of this analysis is to develop a criterion to determine if and when the flow along the WLE experiences turbulent heating given an incoming turbulent boundary layer that contaminates the attachment line. The data to be analyzed were all obtained as part of the MH-13 Space Shuttle Orbiter Aerothermodynamic Test conducted on a 1.8%-scale Orbiter model at Calspan/University of Buffalo Research Center in the Large Energy National Shock Tunnels facility. A rational framework was used to develop a means to assess the state of the WLE flow on the Orbiter during reentry given a contaminated attachment-line flow. Evidence of turbulent flow on the WLE has been recently documented for a few STS missions during the Orbiter s flight history, albeit late in the reentry trajectory. The criterion developed herein will be compared to these flight results.

  5. Approaching time is important for assessment of endoscopic surgical skills.

    Science.gov (United States)

    Tokunaga, Masakazu; Egi, Hiroyuki; Hattori, Minoru; Yoshimitsu, Masanori; Sumitani, Daisuke; Kawahara, Tomohiro; Okajima, Masazumi; Ohdan, Hideki

    2012-05-01

    This study aimed to verify whether the approaching time (the time taken to reach the target point from another point, a short distance apart, during point-to-point movement in endoscopic surgery), assessed using the Hiroshima University Endoscopic Surgical Assessment Device (HUESAD), could distinguish the skill level of surgeons. Expert surgeons (who had performed more than 50 endoscopic surgeries) and novice surgeons (who had no experience in performing endoscopic surgery) were tested using the HUESAD. The approaching time, total time, and intermediate time (total time--approaching time) were measured and analyzed using the trajectory of the tip of the instrument. The approaching time and total time were significantly shorter in the expert group than in the novice group (p time did not significantly differ between the groups (p > 0.05). The approaching time, which is a component of the total time, is very mportant in the measurement of the total time to assess endoscopic surgical skills. Further, the approaching time was useful for skill assessment by the HUESAD for evaluating the skill of surgeons performing endoscopic surgery.

  6. Evaluating the Effect of Lead Time on Quality Service Delivery in the Banking Industry in Kumasi Metropolis of Ghana

    Directory of Open Access Journals (Sweden)

    Stephen Okyere

    2015-07-01

    Full Text Available Customers are becoming more attracted to quality service delivery and are being impatience and unsatisfied when they had to be delayed or wait for longer times before they are served.  Hence, Quality Service Delivery is of utmost importance to every service organisation especially financial industry. Most financial institutions focus attention on product innovation at the expense of lead time management which is a major factor in ensuring service quality and customer satisfaction. Consequently, this research looks at evaluating the effect of lead time on quality service delivery in the Banking Industry in Kumasi Metropolis of Ghana. The study relied on Primary data collected through questionnaires, observation and interview instruments, administered to staff and customers of some selected branches of a commercial bank in the study area. The data was analysed qualitatively. The researchers realised that despite the immense importance of lead time on quality service delivery, little attention is given to the concept. It was revealed that, customers were dissatisfied with the commercial bank’s services as a result of the unnecessary delays and queuing at the bank premises. The long lead time was found to be attributable to plant/system failure, skill gap on the part of employees, ATM underutilization and frequent breakdowns, among others. This has consequently resulted into long lead time, waiting, queuing and unnecessary delay at the banking hall. It is recommended that Tellers should be provided with electronic card readers for verification of customer’s data and processing to be faster.

  7. Lead Time to Appointment and No-Show Rates for New and Follow-up Patients in an Ambulatory Clinic.

    Science.gov (United States)

    Drewek, Rupali; Mirea, Lucia; Adelson, P David

    High rates of no-shows in outpatient clinics are problematic for revenue and for quality of patient care. Longer lead time to appointment has variably been implicated as a risk factor for no-shows, but the evidence within pediatric clinics is inconclusive. The goal of this study was to estimate no-show rates and test for association between appointment lead time and no-show rates for new and follow-up patients. Analyses included 534 new and 1920 follow-up patients from pulmonology and gastroenterology clinics at a freestanding children's hospital. The overall rate of no-shows was lower for visits scheduled within 0 to 30 days compared with 30 days or more (23% compared with 47%, P < .0001). Patient type significantly modified the association of appointment lead time; the rate of no-shows was higher (30%) among new patients compared with (21%) follow-up patients with appointments scheduled within 30 days (P = .004). For appointments scheduled 30 or more days' lead time, no-show rates were statistically similar for new patients (46%) and follow-up patients (0.48%). Time to appointment is a risk factor associated with no-shows, and further study is needed to identify and implement effective approaches to reduce appointment lead time, especially for new patients in pediatric subspecialties.

  8. Prospective Predictors of Suicidality: Defeat and Entrapment Lead to Changes in Suicidal Ideation over Time

    Science.gov (United States)

    Taylor, Peter James; Gooding, Patricia A.; Wood, Alex M.; Johnson, Judith; Tarrier, Nicholas

    2011-01-01

    Theoretical perspectives into suicidality have suggested that heightened perceptions of defeat and entrapment lead to suicidality. However, all previous empirical work has been cross-sectional. We provide the first longitudinal test of the theoretical predictions, in a sample of 79 students who reported suicidality. Participants completed…

  9. Human health risk assessment of lead pollution in atmospheric deposition in Baoshan District, Shanghai.

    Science.gov (United States)

    Chen, Yuanyuan; Wang, Jun; Shi, Guitao; Sun, Xiaojing; Chen, Zhenlou; Xu, Shiyuan

    2011-12-01

    The lead (Pb) content in atmospheric deposition was determined at 42 sampling sites in Baoshan District of Shanghai, China. Based on exposure and dose-response assessments, the health risk caused by Pb exposure in atmospheric deposition was investigated. The results indicated that Pb was significantly accumulated in atmospheric deposition. The spatial distribution of Pb was mapped by geostatistical analysis, and the results showed that pollution hotspots were present at traffic and industrial zones. Ingestion was the main route of Pb exposure in both adults and children. For children the risk value was above 1, whereas it was below 1 for the adult group. Therefore, children belong to the high-risk group for Pb exposure from atmospheric deposition in the observed area of Shanghai, China.

  10. Not feeling well … true or exaggerated? Self-assessed health as a leading health indicator.

    Science.gov (United States)

    Becchetti, Leonardo; Bachelet, Maria; Riccardini, Fabiola

    2018-02-01

    We provide original, international evidence documenting that self-assessed health (SAH) is a leading health indicator, that is, a significant predictor of future changes in health conditions, in a large sample of Europeans aged above 50 and living in 13 different countries. We find that, after controlling for attrition bias, lagged SAH is significantly and negatively correlated with changes in the number of chronic diseases, net of the correlations with levels, and changes in sociodemographic factors and health styles, country and regional health system effects, and declared symptoms. Illness-specific estimates document that lagged SAH significantly correlates with arthritis, cholesterol, and lung diseases (and weakly so with ulcer, hypertension, and cataracts) and has a significant correlation with the probability of contracting cancer. Interpretations and policy implications of our findings are discussed in the paper. Copyright © 2017 John Wiley & Sons, Ltd.

  11. Assessing Management Support for Worksite Health Promotion: Psychometric Analysis of the Leading by Example (LBE) Instrument

    Science.gov (United States)

    Della, Lindsay J.; DeJoy, David M.; Goetzel, Ron Z.; Ozminkowski, Ronald J.; Wilson, Mark G.

    2009-01-01

    Objective This paper describes the development of the Leading by Example (LBE) instrument. Methods Exploratory factor analysis was used to obtain an initial factor structure. Factor validity was evaluated using confirmatory factor analysis methods. Cronbach’s alpha and item-total correlations provided information on the reliability of the factor subscales. Results Four subscales were identified: business alignment with health promotion objectives; awareness of the health-productivity link; worksite support for health promotion; leadership support for health promotion. Factor by group comparisons revealed that the initial factor structure is effective in detecting differences in organizational support for health promotion across different employee groups Conclusions Management support for health promotion can be assessed using the LBE, a brief, self-report questionnaire. Researchers can use the LBE to diagnose, track, and evaluate worksite health promotion programs. PMID:18517097

  12. Engaging narratives evoke similar neural activity and lead to similar time perception.

    Science.gov (United States)

    Cohen, Samantha S; Henin, Simon; Parra, Lucas C

    2017-07-04

    It is said that we lose track of time - that "time flies" - when we are engrossed in a story. How does engagement with the story cause this distorted perception of time, and what are its neural correlates? People commit both time and attentional resources to an engaging stimulus. For narrative videos, attentional engagement can be represented as the level of similarity between the electroencephalographic responses of different viewers. Here we show that this measure of neural engagement predicted the duration of time that viewers were willing to commit to narrative videos. Contrary to popular wisdom, engagement did not distort the average perception of time duration. Rather, more similar brain responses resulted in a more uniform perception of time across viewers. These findings suggest that by capturing the attention of an audience, narrative videos bring both neural processing and the subjective perception of time into synchrony.

  13. Practical Field Survey Approach with Handle Device for Lead Contamination Assessment in Kabwe, Zambia

    Science.gov (United States)

    Nakamura, S.; Hirose, K.; Takeda, T.; Uchida, Y.; Nakata, H.; Nakayama, S.; Ishizuka, M.; Yabe, J.; Ito, M.; Igarashi, T.

    2017-12-01

    International joint research project for assessing lead soil contamination in Kabwe, Zambia was started by Zambian and Japanese scientists in 2008. Various scientific data and results have been obtained up to now. Data sharing among researchers and government officials is necessary for understanding current situation of lead contamination in Kabwe comprehensively. As lead contamination affects on local communities seriously, local community participation is important to solve the environmental issue in near future. This study, therefore, aims to develop GIS Data Integration System (GDIS as followed) consisted of GIS Data Sharing System (GDSS as followed) as web-GIS, FIELDNAUT as Android App for field survey and opensource SNS instance named Mastodon. GDIS will provide local communities to participate easily and support researchers to collect and understand about everyday situation and visualize lead contamination status in Kabwe, Zambia. GDIS is developed with opensource programs. GDSS was simply designed and developed on one desktop PC (Hirose et al., 2015) although common web-GIS requires many servers (Suresh et al., 2015). FIELDNAUT was developed in 2016. FIELDNAUT provides researchers plotting their locations on satellite images and thematic maps, filming and texting with their locations, and compiling and sharing data through GDSS. Mastodon will be used as a new FIELDNAUT communication function between local communities and researchers. It is an independent SNS instance, and the closed and secure communication system will be able to be developed. With this function, local communities will share photos and texts about their daily lives and situation around Kabwe by FIELDNAUT, and those data will be collected into GDSS. Researchers provide their results as hazard maps to local communities through FIELDNAUT. GDIS consisted of GDSS, FIELDNAUT and Mastodon encourages local community participation and let local communities be interested in their environmental issues

  14. Elevated Blood Lead Levels by Length of Time From Resettlement to Health Screening in Kentucky Refugee Children.

    Science.gov (United States)

    Kotey, Stanley; Carrico, Ruth; Wiemken, Timothy Lee; Furmanek, Stephen; Bosson, Rahel; Nyantakyi, Florence; VanHeiden, Sarah; Mattingly, William; Zierold, Kristina M

    2018-02-01

    To examine elevated blood lead levels (EBLLs) in refugee children by postrelocation duration with control for several covariates. We assessed EBLLs (≥ 5µg/dL) between 2012 and 2016 of children younger than 15 years (n = 1950) by the duration of resettlement to health screening by using logistic regression, with control for potential confounders (gender, region of birth, age of housing, and intestinal infestation) in a cross-sectional study. Prevalence of EBLLs was 11.2%. Length of time from resettlement to health screening was inversely associated with EBLLs (tertile 2 unadjusted odds ratio [OR] = 0.79; 95% confidence interval [CI] = 0.56, 1.12; tertile 3 OR = 0.62; 95% CI = 0.42, 0.90; tertile 2 adjusted odds ratio [AOR] = 0.62; 95% CI = 0.39, 0.97; tertile 3 AOR = 0.57; 95% CI = 0.34, 0.93). There was a significant interaction between intestinal infestation and age of housing (P resettlement in unadjusted and adjusted models. Improved housing, early education, and effective safe-house inspections may be necessary to address EBLLs in refugees.

  15. Bioaccessibility and human health risk assessment of lead in soil from Daye City

    Science.gov (United States)

    Li, Q.; Li, F.; Xiao, M. S.; Cai, Y.; Xiong, L.; Huang, J. B.; Fu, J. T.

    2018-01-01

    Lead (Pb) in soil from 4 sampling sites of Daye City was studied. Bioaccessibilities of Pb in soil were determined by the method of simplified bioaccessible extraction test (SBET). Since traditional health risk assessment was built on the basis of metal total content, the risk may be overestimated. Modified human health risk assessment model considering bioaccessibility was built in this study. Health risk of adults and children exposure to Pb based on total contents and bioaccessible contents were evaluated. The results showed that bioaccessible content of Pb in soil was much lower than its total content, and the average bioaccessible factor (BF) was only 25.37%. The hazard indexes (HIs) for adults and children calculated by two methods were all lower than 1. It indicated that there were no no-carcinogenic risks of Pb for human in Daye. By comparing with the results, the average bioaccessible HIs for adults and children were lower than the total one, which was due to the lower hazard quotient (HQ). Proportions of non-carcinogenic risk exposure to Pb via different pathways have also changed. Particularly, the most main risk exposure pathway for adults turned from the oral ingestion to the inhalation.

  16. Assessment of blood lead level declines in an area of historical mining with a holistic remediation and abatement program.

    Science.gov (United States)

    Schoof, Rosalind A; Johnson, Dina L; Handziuk, Emma R; Landingham, Cynthia Van; Feldpausch, Alma M; Gallagher, Alexa E; Dell, Linda D; Kephart, Amy

    2016-10-01

    Lead exposure and blood lead levels (BLLs) in the United States have declined dramatically since the 1970s as many widespread lead uses have been discontinued. Large scale mining and mineral processing represents an additional localized source of potential lead exposure in many historical mining communities, such as Butte, Montana. After 25 years of ongoing remediation efforts and a residential metals abatement program that includes blood lead monitoring of Butte children, examination of blood lead trends offers a unique opportunity to assess the effectiveness of Butte's lead source and exposure reduction measures. This study examined BLL trends in Butte children ages 1-5 (n= 2796) from 2003-2010 as compared to a reference dataset matched for similar demographic characteristics over the same period. Blood lead differences across Butte during the same period are also examined. Findings are interpreted with respect to effectiveness of remediation and other factors potentially contributing to ongoing exposure concerns. BLLs from Butte were compared with a reference dataset (n=2937) derived from the National Health and Nutrition Examination Survey. The reference dataset was initially matched for child age and sample dates. Additional demographic factors associated with higher BLLs were then evaluated. Weights were applied to make the reference dataset more consistent with the Butte dataset for the three factors that were most disparate (poverty-to-income ratio, house age, and race/ethnicity). A weighted linear mixed regression model showed Butte geometric mean BLLs were higher than reference BLLs for 2003-2004 (3.48vs. 2.05µg/dL), 2005-2006 (2.65vs. 1.80µg/dL), and 2007-2008 (2.2vs. 1.72µg/dL), but comparable for 2009-2010 (1.53vs. 1.51µg/dL). This trend suggests that, over time, the impact of other factors that may be associated with Butte BLLs has been reduced. Neighborhood differences were examined by dividing the Butte dataset into the older area called "Uptown

  17. Life cycle assessment (LCA of lead-free solders from the environmental protection aspect

    Directory of Open Access Journals (Sweden)

    Mitovski Aleksandra M.

    2009-01-01

    Full Text Available Life-cycle assessment (LCA presents a relatively new approach, which allows comprehensive environmental consequences analysis of a product system over its entire life. This analysis is increasingly being used in the industry, as a tool for investigation of the influence of the product system on the environment, and serves as a protection and prevention tool in ecological management. This method is used to predict possible influences of a certain material to the environment through different development stages of the material. In LCA, the product systems are evaluated on a functionally equivalent basis, which, in this case, was 1000 cubic centimeters of an alloy. Two of the LCA phases, life-cycle inventory (LCA and life-cycle impact assessment (LCIA, are needed to calculate the environmental impacts. Methodology of LCIA applied in this analysis aligns every input and output influence into 16 different categories, divided in two subcategories. The life-cycle assessment reaserch review of the leadfree solders Sn-Cu, SAC (Sn-Ag-Cu, BSA (Bi-Sb-Ag and SABC (Sn-Ag-Bi-Cu respectively, is given in this paper, from the environmental protection aspect starting from production, through application process and finally, reclamation at the end-of-life, i.e. recycling. There are several opportunities for reducing the overall environmental and human health impacts of solder used in electronics manufacturing based on the results of the LCA, such as: using secondary metals reclaimed through post-industrial recycling; power consumption reducing by replacing older, less efficient reflow assembly equipment, or by optimizing the current equipment to perform at the elevated temperatures required for lead-free soldering, etc. The LCA analysis was done comparatively in relation to widely used Sn-Pb solder material. Additionally, the impact factors of material consumption, energy use, water and air reserves, human health and ecotoxicity have been ALSO considered including

  18. Increased Total Anesthetic Time Leads to Higher Rates of Surgical Site Infections in Spinal Fusions.

    Science.gov (United States)

    Puffer, Ross C; Murphy, Meghan; Maloney, Patrick; Kor, Daryl; Nassr, Ahmad; Freedman, Brett; Fogelson, Jeremy; Bydon, Mohamad

    2017-06-01

    A retrospective review of a consecutive series of spinal fusions comparing patient and procedural characteristics of patients who developed surgical site infections (SSIs) after spinal fusion. It is known that increased surgical time (incision to closure) is associated with a higher rate of postoperative SSIs. We sought to determine whether increased total anesthetic time (intubation to extubation) is a factor in the development of SSIs as well. In spine surgery for deformity and degenerative disease, SSI has been associated with operative time, revealing a nearly 10-fold increase in SSI rates in prolonged surgery. Surgical time is associated with infections in other surgical disciplines as well. No studies have reported whether total anesthetic time (intubation to extubation) has an association with SSIs. Surgical records were searched in a retrospective fashion to identify all spine fusion procedures performed between January 2010 and July 2012. All SSIs during that timeframe were recorded and compared with the list of cases performed between 2010 and 2012 in a case-control design. There were 20 (1.7%) SSIs in this fusion cohort. On univariate analyses of operative factors, there was a significant association between total anesthetic time (Infection 7.6 ± 0.5 hrs vs. no infection -6.0 ± 0.1 hrs, P operative time (infection 5.5 ± 0.4 hrs vs. no infection - 4.4 ± 0.06 hrs, P infections, whereas level of pathology and emergent surgery were not significant. On multivariate logistic analysis, BMI and total anesthetic time remained independent predictors of SSI whereas ASA status and operative time did not. Increasing BMI and total anesthetic time were independent predictors of SSIs in this cohort of over 1000 consecutive spinal fusions. 3.

  19. Evolving Trends in Endodontic Research: An Assessment of Published Articles in 2 Leading Endodontic Journals.

    Science.gov (United States)

    Tzanetakis, Giorgos N; Stefopoulos, Spyridon; Loizides, Alexios L; Kakavetsos, Vasileios D; Kontakiotis, Evangelos G

    2015-12-01

    The aim of this study was to evaluate and analyze the evolving trends in endodontic research in 2 leading endodontic journals (ie, Journal of Endodontics and International Endodontic Journal) in articles published from January 2009 to December 2013. The differences in content between this period and a 10-year earlier period from January 1999 to December 2003 were also evaluated. Each journal's content was accessed through the web edition. For each article, the following parameters were recorded: number of authors, article type, number of affiliations, field of study, source of article, and geographic origin. The recorded data were analyzed using both descriptive and analytic statistics. During 2009-2013 (second period), the mean number of authors per article increased significantly compared with 1999-2003 (first period). The main volume of the literature in both periods and journals was original research articles. The number of published reviews increased significantly from the first to the second study period in contrast to case reports/clinical articles, which presented a significant decrease. "Endodontic materials" was the most prevalent thematic category in both study periods. The number of published articles related to "biology" and "chemical preparation and disinfection" increased significantly from the first to the second study period. On the contrary, the number of articles regarding "obturation and microleakage" presented a considerable decrease at the same time. The United States was the leading country in the number of publications in the first period followed by Brazil. In the second period, this rank was reversed with Brazil becoming the leading country followed by the United States. In the last 15 years, the progress of the specialty of endodontology was apparent as shown through the trends and shifts in research orientation in published articles in the 2 leading endodontic journals. The results of the present reviewing process encourage both journals

  20. Errors in Postural Preparation Lead to Increased Choice Reaction Times for Step Initiation in Older Adults

    Science.gov (United States)

    Nutt, John G.; Horak, Fay B.

    2011-01-01

    Background. This study asked whether older adults were more likely than younger adults to err in the initial direction of their anticipatory postural adjustment (APA) prior to a step (indicating a motor program error), whether initial motor program errors accounted for reaction time differences for step initiation, and whether initial motor program errors were linked to inhibitory failure. Methods. In a stepping task with choice reaction time and simple reaction time conditions, we measured forces under the feet to quantify APA onset and step latency and we used body kinematics to quantify forward movement of center of mass and length of first step. Results. Trials with APA errors were almost three times as common for older adults as for younger adults, and they were nine times more likely in choice reaction time trials than in simple reaction time trials. In trials with APA errors, step latency was delayed, correlation between APA onset and step latency was diminished, and forward motion of the center of mass prior to the step was increased. Participants with more APA errors tended to have worse Stroop interference scores, regardless of age. Conclusions. The results support the hypothesis that findings of slow choice reaction time step initiation in older adults are attributable to inclusion of trials with incorrect initial motor preparation and that these errors are caused by deficits in response inhibition. By extension, the results also suggest that mixing of trials with correct and incorrect initial motor preparation might explain apparent choice reaction time slowing with age in upper limb tasks. PMID:21498431

  1. Time-lapse imaging of neural development: zebrafish lead the way into the fourth dimension.

    Science.gov (United States)

    Rieger, Sandra; Wang, Fang; Sagasti, Alvaro

    2011-07-01

    Time-lapse imaging is often the only way to appreciate fully the many dynamic cell movements critical to neural development. Zebrafish possess many advantages that make them the best vertebrate model organism for live imaging of dynamic development events. This review will discuss technical considerations of time-lapse imaging experiments in zebrafish, describe selected examples of imaging studies in zebrafish that revealed new features or principles of neural development, and consider the promise and challenges of future time-lapse studies of neural development in zebrafish embryos and adults. Copyright © 2011 Wiley-Liss, Inc.

  2. Assessment of time management attitudes among health managers.

    Science.gov (United States)

    Sarp, Nilgun; Yarpuzlu, Aysegul Akbay; Mostame, Fariba

    2005-01-01

    These days, working people are finding it difficult to manage their time, get more done at work, and find some balance in their work and personal lives. Successful time management is often suggested to be a product of organizing skills, however, what works for one person may not work for others. Context current competence assessment formats for physicians, health professionals, and managers during their training years reliably test core knowledge and basic skills. However, they may underemphasize some important domains of professional medical practice. Thus, in addition to assessments of basic skills, new formats that assess clinical reasoning, expert judgment, management of ambiguity, professionalism, time management, learning strategies, and teamwork to promise a multidimensional assessment while maintaining adequate reliability and validity in classic health education and health care institutional settings are needed to be worked on. It should be kept in mind that institutional support, reflection, and mentoring must accompany the development of assessment programs. This study was designed to describe the main factors that consume time, effective hours of work, time management opportunities, and attitudes and behaviors of health professionals and managers on time management concept through assessment by the assessment tool Time Management Inquiry Form (TMIQ-F). The study was conducted at the State Hospital, Social Security Hospital, and University Hospital at Kirikkale, Turkey between October 1999 and January 2000, including 143 subjects defined as medical managers and medical specialists. According to the results, a manager should give priority to the concept of planning, which may be counted among the efficient time management techniques, and educate him/herself on time management.

  3. Matching times of leading and following suggest cooperation through direct reciprocity during V-formation flight in ibis.

    Science.gov (United States)

    Voelkl, Bernhard; Portugal, Steven J; Unsöld, Markus; Usherwood, James R; Wilson, Alan M; Fritz, Johannes

    2015-02-17

    One conspicuous feature of several larger bird species is their annual migration in V-shaped or echelon formation. When birds are flying in these formations, energy savings can be achieved by using the aerodynamic up-wash produced by the preceding bird. As the leading bird in a formation cannot profit from this up-wash, a social dilemma arises around the question of who is going to fly in front? To investigate how this dilemma is solved, we studied the flight behavior of a flock of juvenile Northern bald ibis (Geronticus eremita) during a human-guided autumn migration. We could show that the amount of time a bird is leading a formation is strongly correlated with the time it can itself profit from flying in the wake of another bird. On the dyadic level, birds match the time they spend in the wake of each other by frequent pairwise switches of the leading position. Taken together, these results suggest that bald ibis cooperate by directly taking turns in leading a formation. On the proximate level, we propose that it is mainly the high number of iterations and the immediacy of reciprocation opportunities that favor direct reciprocation. Finally, we found evidence that the animals' propensity to reciprocate in leading has a substantial influence on the size and cohesion of the flight formations.

  4. Variation in pre-treatment count lead time and its effect on baseline estimates of cage-level sea lice abundance.

    Science.gov (United States)

    Gautam, R; Boerlage, A S; Vanderstichel, R; Revie, C W; Hammell, K L

    2016-11-01

    Treatment efficacy studies typically use pre-treatment sea lice abundance as the baseline. However, the pre-treatment counting window often varies from the day of treatment to several days before treatment. We assessed the effect of lead time on baseline estimates, using historical data (2010-14) from a sea lice data management programme (Fish-iTrends). Data were aggregated at the cage level for three life stages: (i) chalimus, (ii) pre-adult and adult male and (iii) adult female. Sea lice counts were log-transformed, and mean counts by lead time relative to treatment day were computed and compared separately for each life stage, using linear mixed models. There were 1,658 observations (treatment events) from 56 sites in 5 Bay Management Areas. Our study showed that lead time had a significant effect on the estimated sea lice abundance, which was moderated by season. During the late summer and autumn periods, counting on the day of treatment gave significantly higher values than other days and would be a more appropriate baseline estimate, while during spring and early summer abundance estimates were comparable among counts within 5 days of treatment. A season-based lead time window may be most appropriate when estimating baseline sea lice levels. © 2016 John Wiley & Sons Ltd.

  5. Coupled Heuristic Prediction of Long Lead-Time Accumulated Total Inflow of a Reservoir during Typhoons Using Deterministic Recurrent and Fuzzy Inference-Based Neural Network

    Directory of Open Access Journals (Sweden)

    Chien-Lin Huang

    2015-11-01

    Full Text Available This study applies Real-Time Recurrent Learning Neural Network (RTRLNN and Adaptive Network-based Fuzzy Inference System (ANFIS with novel heuristic techniques to develop an advanced prediction model of accumulated total inflow of a reservoir in order to solve the difficulties of future long lead-time highly varied uncertainty during typhoon attacks while using a real-time forecast. For promoting the temporal-spatial forecasted precision, the following original specialized heuristic inputs were coupled: observed-predicted inflow increase/decrease (OPIID rate, total precipitation, and duration from current time to the time of maximum precipitation and direct runoff ending (DRE. This study also investigated the temporal-spatial forecasted error feature to assess the feasibility of the developed models, and analyzed the output sensitivity of both single and combined heuristic inputs to determine whether the heuristic model is susceptible to the impact of future forecasted uncertainty/errors. Validation results showed that the long lead-time–predicted accuracy and stability of the RTRLNN-based accumulated total inflow model are better than that of the ANFIS-based model because of the real-time recurrent deterministic routing mechanism of RTRLNN. Simulations show that the RTRLNN-based model with coupled heuristic inputs (RTRLNN-CHI, average error percentage (AEP/average forecast lead-time (AFLT: 6.3%/49 h can achieve better prediction than the model with non-heuristic inputs (AEP of RTRLNN-NHI and ANFIS-NHI: 15.2%/31.8% because of the full consideration of real-time hydrological initial/boundary conditions. Besides, the RTRLNN-CHI model can promote the forecasted lead-time above 49 h with less than 10% of AEP which can overcome the previous forecasted limits of 6-h AFLT with above 20%–40% of AEP.

  6. EU ambition to build the world's leading bioeconomy-Uncertain times demand innovative and sustainable solutions.

    Science.gov (United States)

    Bell, John; Paula, Lino; Dodd, Thomas; Németh, Szilvia; Nanou, Christina; Mega, Voula; Campos, Paula

    2018-01-25

    This article outlines the current context and the development of the European Bioeconomy Strategy. It analyses the current situation, challenges and needs for EU action and concludes with the next steps that the European Commission will undertake to review and update the Bioeconomy Strategy. Bioeconomy offers great opportunities to realising a competitive, circular and sustainable economy with a sound industrial base that is less dependent on fossil carbon. A sustainable bioeconomy also contributes to climate change mitigation, with oceans, forests and soils being major carbon sinks and fostering negative CO 2 emissions. The EU has invested significantly in research and innovation in this field and the European Commission is committed to lead on European bioeconomy strategy. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. Environmental Assessment of Lead at Camp Edwards, Massachusetts, Small Arms Ranges

    National Research Council Canada - National Science Library

    Clausen, Jay L; Korte, Nic; Bostick, Benjamin; Rice, Benjamin; Walsh, Matthew; Nelson, Andrew

    2007-01-01

    ... has or will result in lead mobilization to groundwater. A review of relevant literature and case studies demonstrates lead is toxic to humans and wildlife and, therefore, exposure must be minimized...

  8. Environmental Assessment of Lead at Camp Edwards, Massachusetts, Small Arms Ranges

    National Research Council Canada - National Science Library

    Clausen, Jay L; Korte, Nic; Bostick, Benjamin; Rice, Benjamin; Walsh, Matthew; Nelson, Andrew

    2007-01-01

    Environmental issues for small arms training with lead projectiles are examined in this report for Camp Edwards, Massachusetts, in order to evaluate whether past or future use of lead in small arms...

  9. Extending flood forecasting lead time in a large watershed by coupling WRF QPF with a distributed hydrological model

    Science.gov (United States)

    Li, Ji; Chen, Yangbo; Wang, Huanyu; Qin, Jianming; Li, Jie; Chiao, Sen

    2017-03-01

    Long lead time flood forecasting is very important for large watershed flood mitigation as it provides more time for flood warning and emergency responses. The latest numerical weather forecast model could provide 1-15-day quantitative precipitation forecasting products in grid format, and by coupling this product with a distributed hydrological model could produce long lead time watershed flood forecasting products. This paper studied the feasibility of coupling the Liuxihe model with the Weather Research and Forecasting quantitative precipitation forecast (WRF QPF) for large watershed flood forecasting in southern China. The QPF of WRF products has three lead times, including 24, 48 and 72 h, with the grid resolution being 20 km  × 20 km. The Liuxihe model is set up with freely downloaded terrain property; the model parameters were previously optimized with rain gauge observed precipitation, and re-optimized with the WRF QPF. Results show that the WRF QPF has bias with the rain gauge precipitation, and a post-processing method is proposed to post-process the WRF QPF products, which improves the flood forecasting capability. With model parameter re-optimization, the model's performance improves also. This suggests that the model parameters be optimized with QPF, not the rain gauge precipitation. With the increasing of lead time, the accuracy of the WRF QPF decreases, as does the flood forecasting capability. Flood forecasting products produced by coupling the Liuxihe model with the WRF QPF provide a good reference for large watershed flood warning due to its long lead time and rational results.

  10. How does development lead time affect performance over the ramp-up lifecycle? : evidence from the consumer electronics industry

    NARCIS (Netherlands)

    Pufall, A.A.; Fransoo, J.C.; Jong, de A.; Kok, de A.G.

    2012-01-01

    In the fast-paced world of consumer electronics, short development lead times and efficient product ramp-ups are invaluable. The sooner and faster a firm can ramp-up production of a new product, the faster it can start to earn revenues, profit from early market opportunities, establish technology

  11. Observing expertise-related actions leads to perfect time flow estimations.

    Directory of Open Access Journals (Sweden)

    Yin-Hua Chen

    Full Text Available The estimation of the time of exposure of a picture portraying an action increases as a function of the amount of movement implied in the action represented. This effect suggests that the perceiver creates an internal embodiment of the action observed as if internally simulating the entire movement sequence. Little is known however about the timing accuracy of these internal action simulations, specifically whether they are affected by the level of familiarity and experience that the observer has of the action. In this study we asked professional pianists to reproduce different durations of exposure (shorter or longer than one second of visual displays both specific (a hand in piano-playing action and non-specific to their domain of expertise (a hand in finger-thumb opposition and scrambled-pixels and compared their performance with non-pianists. Pianists outperformed non-pianists independently of the time of exposure of the stimuli; remarkably the group difference was particularly magnified by the pianists' enhanced accuracy and stability only when observing the hand in the act of playing the piano. These results for the first time provide evidence that through musical training, pianists create a selective and self-determined dynamic internal representation of an observed movement that allows them to estimate precisely its temporal duration.

  12. Optimal provisioning strategies for slow moving spare parts with small lead times

    NARCIS (Netherlands)

    Teunter, R.H.; Klein Haneveld, W.K.

    When an expensive piece of equipment is bought, spare parts can often be bought at a reduced price. A decision must be made about the initial provisioning of spare parts. Furthermore, if at a certain time the stock drops to zero, because a number of failures have occurred, a decision must be made

  13. Action and Perception Are Temporally Coupled by a Common Mechanism That Leads to a Timing Misperception

    Science.gov (United States)

    Astefanoaei, Corina; Daye, Pierre M.; FitzGibbon, Edmond J.; Creanga, Dorina-Emilia; Rufa, Alessandra; Optican, Lance M.

    2015-01-01

    We move our eyes to explore the world, but visual areas determining where to look next (action) are different from those determining what we are seeing (perception). Whether, or how, action and perception are temporally coordinated is not known. The preparation time course of an action (e.g., a saccade) has been widely studied with the gap/overlap paradigm with temporal asynchronies (TA) between peripheral target onset and fixation point offset (gap, synchronous, or overlap). However, whether the subjects perceive the gap or overlap, and when they perceive it, has not been studied. We adapted the gap/overlap paradigm to study the temporal coupling of action and perception. Human subjects made saccades to targets with different TAs with respect to fixation point offset and reported whether they perceived the stimuli as separated by a gap or overlapped in time. Both saccadic and perceptual report reaction times changed in the same way as a function of TA. The TA dependencies of the time change for action and perception were very similar, suggesting a common neural substrate. Unexpectedly, in the perceptual task, subjects misperceived lights overlapping by less than ∼100 ms as separated in time (overlap seen as gap). We present an attention-perception model with a map of prominence in the superior colliculus that modulates the stimulus signal's effectiveness in the action and perception pathways. This common source of modulation determines how competition between stimuli is resolved, causes the TA dependence of action and perception to be the same, and causes the misperception. PMID:25632126

  14. A real-time internal dose assessment exercise

    International Nuclear Information System (INIS)

    Bingham, D.; Bull, R. K.

    2013-01-01

    A real-time internal dose assessment exercise has been conducted in which participants were required to make decisions about sampling requirements, seek relevant information about the 'incident' and make various interim dose assessments. At the end of the exercise, each participant was requested to make a formal assessment, providing statements of the methods, models and assumptions used in that assessment. In this paper we describe how the hypothetical assessment case was set up and the exercise was conducted, the responses of the participants and the assessments of dose that they made. Finally we discuss the lessons learnt from the exercise and suggest how the exercise may be adapted to a wider range of participants. (authors)

  15. Reduction of Working Time: Does It Lead to a Healthy Lifestyle?

    Science.gov (United States)

    Ahn, Taehyun

    2016-08-01

    I examine whether working hours have a causal effect on the health behaviors of workers. In assessing the causal relationship, I estimate fixed-effects instrumental variable models by using exogenous variation in adopting a reduced workweek in South Korea as an instrument for work hours. The estimation results reveal that shortening work hours induces individuals to exercise regularly and decreases the likelihood of smoking, with more pronounced effects for heavy smokers. While a work-hour reduction substantially increases the probability of drinking participation, it does not significantly affect the likelihood of frequent or daily drinking habits. In addition, the effect of a work-hour reduction on regular exercise is salient among women and older groups, and the effect on smoking behaviors is more pronounced among men and middle-aged groups. Copyright © 2015 John Wiley & Sons, Ltd. Copyright © 2015 John Wiley & Sons, Ltd.

  16. Effective production planning for purchased part under long lead time and uncertain demand: MRP Vs demand-driven MRP

    Science.gov (United States)

    Shofa, M. J.; Moeis, A. O.; Restiana, N.

    2018-04-01

    MRP as a production planning system is appropriate for the deterministic environment. Unfortunately, most production systems such as customer demands are stochastic, so that MRP is inappropriate at the time. Demand-Driven MRP (DDMRP) is new approach for production planning system dealing with demand uncertainty. The objective of this paper is to compare the MRP and DDMRP for purchased part under long lead time and uncertain demand in terms of average inventory levels. The evaluation is conducted through a discrete event simulation with the long lead time and uncertain demand scenarios. The next step is evaluating the performance of DDMRP by comparing the inventory level of DDMRP with MRP. As result, DDMRP is more effective production planning than MRP in terms of average inventory levels.

  17. Waiting time distribution for the first conception leading to a live birth

    International Nuclear Information System (INIS)

    Shrestha, G.; Biswas, S.

    1985-01-01

    An attempt has been made in this paper to obtain probability model describing the distribution of the waiting time from marriage to first conception based on the data from marriage to first live birth. The speciality of this present approach lies in assuming the marital exposure to be finite which was assumed to be infinite by most of the earlier investigators for mathematical simplicity. Illustration of the applicability of the model on the data pertaining to first order of conception and monthly probability of conception for women married at different age groups have been illustrated in this paper. (author)

  18. Sleep restriction may lead to disruption in physiological attention and reaction time

    Directory of Open Access Journals (Sweden)

    Arbind Kumar Choudhary

    2016-07-01

    Full Text Available Sleepiness is the condition where for some reason fails to go into a sleep state and will have difficulty in remaining awake even while carrying out activities. Sleep restriction occurs when an individual fails to get enough sleep due to high work demands. The mechanism between sleep restriction and underlying brain physiology deficits is not well assumed. The objective of the present study was to investigate the mental attention (P300 and reaction time [visual (VRT and auditory (ART] among night watchmen, at subsequent; first (1st day, fourth (4th day and seventh (7th day of restricted sleep period. After exclusion and inclusion criteria, the study was performed among 50 watchmen (age=18–35 years (n=50 after providing written informed consent and divided into two group. Group I-(Normal sleep (n=28 working in day time and used to have normal sleep in night (≥8 h; Group II-(Restricted sleep (n=22 - working in night time and used to have less sleep in night (≤3 h. Statistical significance between the different groups was determined by the independent student ʻtʼ test and the significance level was fixed at p≤0.05. We observed that among all normal and restricted sleep watchmen there was not any significant variation in Karolinska Sleepiness Scale (KSS score, VRT and ART, along with latency and amplitude of P300 on 1st day of restricted sleep. However at subsequent on 4th day and 7th day of restricted sleep, there was significant increase in (KSSscore, and prolongation of VRT and ART as well as alteration in latency and amplitude of P300 wave in restricted sleep watchmen when compare to normal sleep watchmen. The present finding concludes that loss of sleep has major impact in dynamic change in mental attention and reaction time among watchmen employed in night shift. Professional regulations and work schedules should integrate sleep schedules before and during the work period as an essential dimension for their healthy life.

  19. Sleep restriction may lead to disruption in physiological attention and reaction time.

    Science.gov (United States)

    Choudhary, Arbind Kumar; Kishanrao, Sadawarte Sahebrao; Dadarao Dhanvijay, Anup Kumar; Alam, Tanwir

    2016-01-01

    Sleepiness is the condition where for some reason fails to go into a sleep state and will have difficulty in remaining awake even while carrying out activities. Sleep restriction occurs when an individual fails to get enough sleep due to high work demands. The mechanism between sleep restriction and underlying brain physiology deficits is not well assumed. The objective of the present study was to investigate the mental attention (P300) and reaction time [visual (VRT) and auditory (ART)] among night watchmen, at subsequent; first (1st) day, fourth (4th) day and seventh (7th) day of restricted sleep period. After exclusion and inclusion criteria, the study was performed among 50 watchmen (age=18-35 years) (n=50) after providing written informed consent and divided into two group. Group I-(Normal sleep) (n=28) working in day time and used to have normal sleep in night (≥8 h); Group II-(Restricted sleep) (n=22) - working in night time and used to have less sleep in night (≤3 h). Statistical significance between the different groups was determined by the independent student ' t ' test and the significance level was fixed at p≤0.05. We observed that among all normal and restricted sleep watchmen there was not any significant variation in Karolinska Sleepiness Scale (KSS) score, VRT and ART, along with latency and amplitude of P300 on 1st day of restricted sleep. However at subsequent on 4th day and 7th day of restricted sleep, there was significant increase in (KSS)score, and prolongation of VRT and ART as well as alteration in latency and amplitude of P300 wave in restricted sleep watchmen when compare to normal sleep watchmen. The present finding concludes that loss of sleep has major impact in dynamic change in mental attention and reaction time among watchmen employed in night shift. Professional regulations and work schedules should integrate sleep schedules before and during the work period as an essential dimension for their healthy life.

  20. Lead pellet retention time and associated toxicity in northern bobwhite quail (Colinus virginianus).

    Science.gov (United States)

    Kerr, Richard; Holladay, Steven; Jarrett, Timothy; Selcer, Barbara; Meldrum, Blair; Williams, Susan; Tannenbaum, Lawrence; Holladay, Jeremy; Williams, Jamie; Gogal, Robert

    2010-12-01

    Birds are exposed to Pb by oral ingestion of spent Pb shot as grit. A paucity of data exists for retention and clearance of these particles in the bird gastrointestinal tract. In the current study, northern bobwhite quail (Colinus virginianus) were orally gavaged with 1, 5, or 10 Pb shot pellets, of 2-mm diameter, and radiographically followed over time. Blood Pb levels and other measures of toxicity were collected, to correlate with pellet retention. Quail dosed with either 5 or 10 pellets exhibited morbidity between weeks 1 and 2 and were removed from further study. Most of the Pb pellets were absorbed or excreted within 14 d of gavage, independent of dose. Pellet size in the ventriculus decreased over time in radiographs, suggesting dissolution caused by the acidic pH. Birds dosed with one pellet showed mean blood Pb levels that exceeded 1,300 µg/dl at week 1, further supporting dissolution in the gastrointestinal tract. Limited signs of toxicity were seen in the one-pellet birds; however, plasma δ-aminolevulinic acid dehydratase (d-ALAD) activity was persistently depressed, suggesting possible impaired hematological function. © 2010 SETAC.

  1. Permutation entropy based time series analysis: Equalities in the input signal can lead to false conclusions

    Energy Technology Data Exchange (ETDEWEB)

    Zunino, Luciano, E-mail: lucianoz@ciop.unlp.edu.ar [Centro de Investigaciones Ópticas (CONICET La Plata – CIC), C.C. 3, 1897 Gonnet (Argentina); Departamento de Ciencias Básicas, Facultad de Ingeniería, Universidad Nacional de La Plata (UNLP), 1900 La Plata (Argentina); Olivares, Felipe, E-mail: olivaresfe@gmail.com [Instituto de Física, Pontificia Universidad Católica de Valparaíso (PUCV), 23-40025 Valparaíso (Chile); Scholkmann, Felix, E-mail: Felix.Scholkmann@gmail.com [Research Office for Complex Physical and Biological Systems (ROCoS), Mutschellenstr. 179, 8038 Zurich (Switzerland); Biomedical Optics Research Laboratory, Department of Neonatology, University Hospital Zurich, University of Zurich, 8091 Zurich (Switzerland); Rosso, Osvaldo A., E-mail: oarosso@gmail.com [Instituto de Física, Universidade Federal de Alagoas (UFAL), BR 104 Norte km 97, 57072-970, Maceió, Alagoas (Brazil); Instituto Tecnológico de Buenos Aires (ITBA) and CONICET, C1106ACD, Av. Eduardo Madero 399, Ciudad Autónoma de Buenos Aires (Argentina); Complex Systems Group, Facultad de Ingeniería y Ciencias Aplicadas, Universidad de los Andes, Av. Mons. Álvaro del Portillo 12.455, Las Condes, Santiago (Chile)

    2017-06-15

    A symbolic encoding scheme, based on the ordinal relation between the amplitude of neighboring values of a given data sequence, should be implemented before estimating the permutation entropy. Consequently, equalities in the analyzed signal, i.e. repeated equal values, deserve special attention and treatment. In this work, we carefully study the effect that the presence of equalities has on permutation entropy estimated values when these ties are symbolized, as it is commonly done, according to their order of appearance. On the one hand, the analysis of computer-generated time series is initially developed to understand the incidence of repeated values on permutation entropy estimations in controlled scenarios. The presence of temporal correlations is erroneously concluded when true pseudorandom time series with low amplitude resolutions are considered. On the other hand, the analysis of real-world data is included to illustrate how the presence of a significant number of equal values can give rise to false conclusions regarding the underlying temporal structures in practical contexts. - Highlights: • Impact of repeated values in a signal when estimating permutation entropy is studied. • Numerical and experimental tests are included for characterizing this limitation. • Non-negligible temporal correlations can be spuriously concluded by repeated values. • Data digitized with low amplitude resolutions could be especially affected. • Analysis with shuffled realizations can help to overcome this limitation.

  2. Lead-acid batteries life time prolongation in renewable energy source plants

    Directory of Open Access Journals (Sweden)

    Костянтин Ігорович Ткаченко

    2015-11-01

    Full Text Available Charge controllers with microprocessor control are recognized to be almost optimal process control devices for collecting and storing energy in batteries in power systems with renewable energy sources such as solar photoelectric batteries, wind electrogenerators and others. The task of the controller is charging process control, that is such as charging and discharging the batteries while providing maximum charging speed and battery saving parameters that characterize the state of the battery, within certain limits, preventing overcharging, overheating and the batteries deep discharge. The possibility of archiving data that keeps the battery parameters time dependance is also important. Thus, the concept of a charge controller with Texas Instruments microcontroller device MSP430G2553 was introduced in the study. The program saved in the ROM microcontroller provides for: charge regime(with a particular algorithm; control and training cycle followed by charging; continuous charge-discharge regime to restore the battery or the study of charge regime algorithms influence on repair effectiveness. The device can perform its functions without being connected to a personal computer, but this connection makes it possible to observe in real time the characteristics of a number of discharge and charge regimes parameters, as well as reading the stored data from microcontroller flash memory and storing these data on the PC hard disk for further analysis. A four stages charging algorithm with reverse charging regime was offered by the author and correctness of algorithm was proved

  3. Assessment of semen function and lipid peroxidation among lead exposed men

    International Nuclear Information System (INIS)

    Kasperczyk, Aleksandra; Kasperczyk, Slawomir; Horak, Stanislaw; Ostalowska, Alina; Grucka-Mamczar, Ewa; Romuk, Ewa; Olejek, Anita; Birkner, Ewa

    2008-01-01

    The study population included healthy, fertile men, employees of Zinc and Lead Metalworks (n = 63). Workers exposed to lead were divided into two groups: a group with moderate exposure to lead (ME) - blood lead level (PbB) 25-40 μg/dl and a group with high exposure to lead (HE) PbB = 40-81 μg/dl. The control group consisted of office workers with no history of occupational exposure to lead. Evaluation of lead, cadmium and zinc level in blood and seminal plasma, zinc protoporphyrin in blood (ZPP), 5-aminolevulinic acid in urine (ALA), malondialdehyde (MDA) in seminal plasma and sperm analysis were performed. No differences were noted in the concentration of cadmium and zinc in blood and seminal plasma in the study population. Lipid peroxidation in seminal plasma, represented as MDA concentration, significantly increased by about 56% in the HE group and the percentage of motile sperm cells after 1 h decreased by about 34% in comparison to the control group. No statistically significant correlation between other parameters of sperm analysis and lead exposure parameters nor between lead, cadmium and zinc concentration in blood and seminal plasma were found. A positive association between lead intoxication parameters (PbB, ZPP, lead seminal plasma) and MDA concentration in sperm plasma and inverse correlation with sperm cells motility (PbB, ZPP) was found. An increased concentration of MDA was accompanied by a drop in sperm cells motility. In conclusion, we report that high exposure to lead causes a decrease of sperm motility in men most likely as a result of increased lipid peroxidation, especially if the level in the blood surpasses the concentration of 40 μg/dl

  4. Why shorter half-times of repair lead to greater damage in pulsed brachytherapy

    International Nuclear Information System (INIS)

    Fowler, J.F.

    1993-01-01

    Pulsed brachytherapy consists of replacing continuous irradiation at low dose-rate with a series of medium dose-rate fractions in the same overall time and to the same total dose. For example, pulses of 1 Gy given every 2 hr or 2 Gy given every 4 hr would deliver the same 70 Gy in 140 hr as continuous irradiation at 0.5 Gy/hr. If higher dose-rates are used, even with gaps between the pulses, the biological effects are always greater. Provided that dose rates in the pulse do not exceed 3 Gy/hr, and provided that pulses are given as often as every 2 hr, the inevitable increases of biological effect are no larger than a few percent (of biologically effective dose or extrapolated response dose). However, these increases are more likely to exceed 10% (and thus become clinically significant) if the half-time of repair of sublethal damage is short (less than 1 hr) rather than long. This somewhat unexpected finding is explained in detail here. The rise and fall of Biologically Effective Dose (and hence of Relative Effectiveness, for a constant dose in each pulse) is calculated during and after single pulses, assuming a range of values of T 1/2 , the half-time of sublethal damage repair. The area under each curve is proportional to Biologically Effective Dose and therefore to log cell kill. Pulses at 3 Gy/hr do yield greater biological effect (dose x integrated Relative Effectiveness) than lower dose-rate pulses or continuous irradiation at 0.5 Gy/hr. The contrast is greater for the short T 1/2 of 0.5 hr than for the longer T 1/2 of 1.5 hr. More biological damage will be done (compared with traditional low dose rate brachytherapy) in tissues with short T 1/2 (0.1-1 hr) than in tissues with longer T 1/2 values. 8 refs., 3 figs

  5. Copper, nickel and lead in lichen and tree bark transplants over different periods of time

    Energy Technology Data Exchange (ETDEWEB)

    Baptista, Mafalda S. [CIIMAR, Rua dos Bragas, 289, 4050-123 Porto (Portugal)], E-mail: abaptista@fc.up.pt; Vasconcelos, M. Teresa S.D. [CIIMAR, Rua dos Bragas, 289, 4050-123 Porto (Portugal); Chemistry Department, Faculty of Sciences, University of Porto, Rua do Campo Alegre, 687, 4169-071 Porto (Portugal)], E-mail: mtvascon@fc.up.pt; Cabral, Joao Paulo [CIIMAR, Rua dos Bragas, 289, 4050-123 Porto (Portugal); Botany Department, Faculty of Sciences, University of Porto, Rua do Campo Alegre, 1191, 4150-181 Porto (Portugal)], E-mail: jpcabral@fc.up.pt; Freitas, M. Carmo [ITN - Technological and Nuclear Institute, Reactor E.N. 10, 2686-953 Sacavem (Portugal)], E-mail: cfreitas@itn.mcies.pt; Pacheco, Adriano M.G. [CVRM-IST - Technical University of Lisbon, Avenida Rovisco Pais, 1, 1049-001 Lisbon (Portugal)], E-mail: apacheco@ist.utl.pt

    2008-01-15

    This work aimed at comparing the dynamics of atmospheric metal accumulation by the lichen Flavoparmelia caperata and bark of Platanus hybrida over different periods of time. Transplants were exposed in three Portuguese coastal cities. Samples were retrieved (1) every 2 months (discontinuous exposure), or (2) after 2-, 4-, 6-, 8- and 10-month periods (continuous exposure), and analysed for Cu, Ni and Pb. Airborne accumulation of metals was essentially independent of climatic factors. For both biomonitors [Pb] > [Ni] > [Cu] but Pb was the only element for which a consistent pattern of accumulation was observed, with the bark outperforming the lichen. The longest exposure periods hardly ever corresponded to the highest accumulation. This might have been partly because the biomonitors bound and released metals throughout the exposure, each with its own dynamics of accumulation, but both according to the environmental metal availability. - Lichen and tree bark have distinct dynamics of airborne metal accumulation.

  6. Copper, nickel and lead in lichen and tree bark transplants over different periods of time

    International Nuclear Information System (INIS)

    Baptista, Mafalda S.; Vasconcelos, M. Teresa S.D.; Cabral, Joao Paulo; Freitas, M. Carmo; Pacheco, Adriano M.G.

    2008-01-01

    This work aimed at comparing the dynamics of atmospheric metal accumulation by the lichen Flavoparmelia caperata and bark of Platanus hybrida over different periods of time. Transplants were exposed in three Portuguese coastal cities. Samples were retrieved (1) every 2 months (discontinuous exposure), or (2) after 2-, 4-, 6-, 8- and 10-month periods (continuous exposure), and analysed for Cu, Ni and Pb. Airborne accumulation of metals was essentially independent of climatic factors. For both biomonitors [Pb] > [Ni] > [Cu] but Pb was the only element for which a consistent pattern of accumulation was observed, with the bark outperforming the lichen. The longest exposure periods hardly ever corresponded to the highest accumulation. This might have been partly because the biomonitors bound and released metals throughout the exposure, each with its own dynamics of accumulation, but both according to the environmental metal availability. - Lichen and tree bark have distinct dynamics of airborne metal accumulation

  7. Assessment of lead exposure in Spanish imperial eagle (Aquila adalberti) from spent ammunition in central Spain

    Science.gov (United States)

    Fernandez, Julia Rodriguez-Ramos; Hofle, Ursula; Mateo, Rafael; de Francisco, Olga Nicolas; Abbott, Rachel; Acevedo, Pelayo; Blanco, Juan-Manuel

    2011-01-01

    The Spanish imperial eagle (Aquila adalberti) is found only in the Iberian Peninsula and is considered one of the most threatened birds of prey in Europe. Here we analyze lead concentrations in bones (n = 84), livers (n = 15), primary feathers (n = 69), secondary feathers (n = 71) and blood feathers (n = 14) of 85 individuals collected between 1997 and 2008 in central Spain. Three birds (3.6%) had bone lead concentration > 20 (mu or u)g/g and all livers were within background lead concentration. Bone lead concentrations increased with the age of the birds and were correlated with lead concentration in rachis of secondary feathers. Spatial aggregation of elevated bone lead concentration was found in some areas of Montes de Toledo. Lead concentrations in feathers were positively associated with the density of large game animals in the area where birds were found dead or injured. Discontinuous lead exposure in eagles was evidenced by differences in lead concentration in longitudinal portions of the rachis of feathers.

  8. Effects of multidisciplinary teamwork on lead times and patient flow in the emergency department: a longitudinal interventional cohort study.

    Science.gov (United States)

    Muntlin Athlin, Asa; von Thiele Schwarz, Ulrica; Farrohknia, Nasim

    2013-11-01

    Long waiting times for emergency care are claimed to be caused by overcrowded emergency departments and non-effective working routines. Teamwork has been suggested as a promising solution to these issues. The aim of the present study was to investigate the effects of teamwork in a Swedish emergency department on lead times and patient flow. The study was set in an emergency department of a university hospital where teamwork, a multi-professional team responsible for the whole care process for a group of patients, was introduced. The study has a longitudinal non-randomized intervention study design. Data were collected for five two-week periods during a period of 1.5 years. The first part of the data collection used an ABAB design whereby standard procedure (A) was altered weekly with teamwork (B). Then, three follow-ups were conducted. At last follow-up, teamwork was permanently implemented. The outcome measures were: number of patients handled within teamwork time, time to physician, total visit time and number of patients handled within the 4-hour target. A total of 1,838 patient visits were studied. The effect on lead times was only evident at the last follow-up. Findings showed that the number of patients handled within teamwork time was almost equal between the different study periods. At the last follow-up, the median time to physician was significantly decreased by 11 minutes (p = 0.0005) compared to the control phase and the total visit time was significantly shorter at last follow-up compared to control phase (p = Teamwork seems to contribute to the quality improvement of emergency care in terms of small but significant decreases in lead times. However, although efficient work processes such as teamwork are necessary to ensure safe patient care, it is likely not sufficient for bringing about larger decreases in lead times or for meeting the 4-hour target in the emergency department.

  9. Real-time Color Codes for Assessing Learning Process

    OpenAIRE

    Dzelzkalēja, L; Kapenieks, J

    2016-01-01

    Effective assessment is an important way for improving the learning process. There are existing guidelines for assessing the learning process, but they lack holistic digital knowledge society considerations. In this paper the authors propose a method for real-time evaluation of students’ learning process and, consequently, for quality evaluation of teaching materials both in the classroom and in the distance learning environment. The main idea of the proposed Color code method (CCM) is to use...

  10. Real Time Face Quality Assessment for Face Log Generation

    DEFF Research Database (Denmark)

    Kamal, Nasrollahi; Moeslund, Thomas B.

    2009-01-01

    Summarizing a long surveillance video to just a few best quality face images of each subject, a face-log, is of great importance in surveillance systems. Face quality assessment is the back-bone for face log generation and improving the quality assessment makes the face logs more reliable....... Developing a real time face quality assessment system using the most important facial features and employing it for face logs generation are the concerns of this paper. Extensive tests using four databases are carried out to validate the usability of the system....

  11. Open source and healthcare in Europe - time to put leading edge ideas into practice.

    Science.gov (United States)

    Murray, Peter J; Wright, Graham; Karopka, Thomas; Betts, Helen; Orel, Andrej

    2009-01-01

    Free/Libre and Open Source Software (FLOSS) is a process of software development, a method of licensing and a philosophy. Although FLOSS plays a significant role in several market areas, the impact in the health care arena is still limited. FLOSS is promoted as one of the most effective means for overcoming fragmentation in the health care sector and providing a basis for more efficient, timely and cost effective health care provision. The 2008 European Federation for Medical Informatics (EFMI) Special Topic Conference (STC) explored a range of current and future issues related to FLOSS in healthcare (FLOSS-HC). In particular, there was a focus on health records, ubiquitous computing, knowledge sharing, and current and future applications. Discussions resulted in a list of main barriers and challenges for use of FLOSS-HC. Based on the outputs of this event, the 2004 Open Steps events and subsequent workshops at OSEHC2009 and Med-e-Tel 2009, a four-step strategy has been proposed for FLOSS-HC: 1) a FLOSS-HC inventory; 2) a FLOSS-HC collaboration platform, use case database and knowledge base; 3) a worldwide FLOSS-HC network; and 4) FLOSS-HC dissemination activities. The workshop will further refine this strategy and elaborate avenues for FLOSS-HC from scientific, business and end-user perspectives. To gain acceptance by different stakeholders in the health care industry, different activities have to be conducted in collaboration. The workshop will focus on the scientific challenges in developing methodologies and criteria to support FLOSS-HC in becoming a viable alternative to commercial and proprietary software development and deployment.

  12. An integrated supply chain inventory model with imperfect-quality items, controllable lead time and distribution-free demand

    Directory of Open Access Journals (Sweden)

    Lin Hsien-Jen

    2013-01-01

    Full Text Available In this paper, we consider an integrated vendor-buyer inventory policy for a continuous review model with a random number of defective items and screening process gradually at a fixed screening rate in buyer’s arriving order lot. We assume that shortages are allowed and partially backlogged on the buyer’s side, and that the lead time demand distribution is unknown, except its first two moments. The objective is to apply the minmax distribution free approach to determine the optimal order quantity, reorder point, lead time and the number of lots delivered in one production run simultaneously so that the expected total system cost is minimized. Numerical experiments along with sensitivity analysis were performed to illustrate the effects of parameters on the decision and the total system cost.

  13. Heart Surgery Waiting Time: Assessing the Effectiveness of an Action

    OpenAIRE

    Badakhshan, Abbas; Arab, Mohammad; Gholipour, Mahin; Behnampour, Naser; Saleki, Saeid

    2015-01-01

    Background: Waiting time is an index assessing patient satisfaction, managerial effectiveness and horizontal equity in providing health care. Although heart surgery centers establishment is attractive for politicians. They are always faced with the question of to what extent they solve patient’s problems. Objectives: The objective of this study was to evaluate factors influencing waiting time in patients of heart surgery centers, and to make recommendations for health-care policy-makers for r...

  14. A single-vendor and a single-buyer integrated inventory model with ordering cost reduction dependent on lead time

    Science.gov (United States)

    Vijayashree, M.; Uthayakumar, R.

    2017-09-01

    Lead time is one of the major limits that affect planning at every stage of the supply chain system. In this paper, we study a continuous review inventory model. This paper investigates the ordering cost reductions are dependent on lead time. This study addressed two-echelon supply chain problem consisting of a single vendor and a single buyer. The main contribution of this study is that the integrated total cost of the single vendor and the single buyer integrated system is analyzed by adopting two different (linear and logarithmic) types ordering cost reductions act dependent on lead time. In both cases, we develop effective solution procedures for finding the optimal solution and then illustrative numerical examples are given to illustrate the results. The solution procedure is to determine the optimal solutions of order quantity, ordering cost, lead time and the number of deliveries from the single vendor and the single buyer in one production run, so that the integrated total cost incurred has the minimum value. Ordering cost reduction is the main aspect of the proposed model. A numerical example is given to validate the model. Numerical example solved by using Matlab software. The mathematical model is solved analytically by minimizing the integrated total cost. Furthermore, the sensitivity analysis is included and the numerical examples are given to illustrate the results. The results obtained in this paper are illustrated with the help of numerical examples. The sensitivity of the proposed model has been checked with respect to the various major parameters of the system. Results reveal that the proposed integrated inventory model is more applicable for the supply chain manufacturing system. For each case, an algorithm procedure of finding the optimal solution is developed. Finally, the graphical representation is presented to illustrate the proposed model and also include the computer flowchart in each model.

  15. Interpretations of systematic errors in the NCEP Climate Forecast System at lead times of 2, 4, 8, ..., 256 days

    Directory of Open Access Journals (Sweden)

    Siwon Song

    2012-09-01

    Full Text Available The climatology of mean bias errors (relative to 1-day forecasts was examined in a 20-year hindcast set from version 1 of the Climate Forecast System (CFS, for forecast lead times of 2, 4, 8, 16, ... 256 days, verifying in different seasons. Results mostly confirm the simple expectation that atmospheric model biases should be evident at short lead (2–4 days, while soil moisture errors develop over days-weeks and ocean errors emerge over months. A further simplification is also evident: surface temperature bias patterns have nearly fixed geographical structure, growing with different time scales over land and ocean. The geographical pattern has mostly warm and dry biases over land and cool bias over the oceans, with two main exceptions: (1 deficient stratocumulus clouds cause warm biases in eastern subtropical oceans, and (2 high latitude land is too cold in boreal winter. Further study of the east Pacific cold tongue-Intertropical Convergence Zone (ITCZ complex shows a possible interaction between a rapidly-expressed atmospheric model bias (poleward shift of deep convection beginning at day 2 and slow ocean dynamics (erroneously cold upwelling along the equator in leads > 1 month. Further study of the high latitude land cold bias shows that it is a thermal wind balance aspect of the deep polar vortex, not just a near-surface temperature error under the wintertime inversion, suggesting that its development time scale of weeks to months may involve long timescale processes in the atmosphere, not necessarily in the land model. Winter zonal wind errors are small in magnitude, but a refractive index map shows that this can cause modest errors in Rossby wave ducting. Finally, as a counterpoint to our initial expectations about error growth, a case of non-monotonic error growth is shown: velocity potential bias grows with lead on a time scale of weeks, then decays over months. It is hypothesized that compensations between land and ocean errors may

  16. Estimate of overdiagnosis of breast cancer due to mammography after adjustment for lead time. A service screening study in Italy

    Science.gov (United States)

    Paci, Eugenio; Miccinesi, Guido; Puliti, Donella; Baldazzi, Paola; De Lisi, Vincenzo; Falcini, Fabio; Cirilli, Claudia; Ferretti, Stefano; Mangone, Lucia; Finarelli, Alba Carola; Rosso, Stefano; Segnan, Nereo; Stracci, Fabrizio; Traina, Adele; Tumino, Rosario; Zorzi, Manuel

    2006-01-01

    Introduction Excess of incidence rates is the expected consequence of service screening. The aim of this paper is to estimate the quota attributable to overdiagnosis in the breast cancer screening programmes in Northern and Central Italy. Methods All patients with breast cancer diagnosed between 50 and 74 years who were resident in screening areas in the six years before and five years after the start of the screening programme were included. We calculated a corrected-for-lead-time number of observed cases for each calendar year. The number of observed incident cases was reduced by the number of screen-detected cases in that year and incremented by the estimated number of screen-detected cases that would have arisen clinically in that year. Results In total we included 13,519 and 13,999 breast cancer cases diagnosed in the pre-screening and screening years, respectively. In total, the excess ratio of observed to predicted in situ and invasive cases was 36.2%. After correction for lead time the excess ratio was 4.6% (95% confidence interval 2 to 7%) and for invasive cases only it was 3.2% (95% confidence interval 1 to 6%). Conclusion The remaining excess of cancers after individual correction for lead time was lower than 5%. PMID:17147789

  17. In vitro time kill assessment of crude methanol extract of ...

    African Journals Online (AJOL)

    The in vitro antibacterial activities and time kill regimes of crude methanol extract of Helichrysum pedunculatum was assessed using standard microbiological procedures. The experiment was conducted against a panel of bacterial species made up of clinical, environmental and reference strains. The extract was active ...

  18. Assessment of the toxic stress of lead on Clarias gariepinus (African ...

    African Journals Online (AJOL)

    6; 101 –104 (2003). Original article ... The toxic stress of lead on fish was tested employing a 96-hour bioassay test. The ... This work is therefore aimed at ... Water was changed every other day. .... like Sweden, Japan, Switzerland and.

  19. Superior Reproducibility of the Leading to Leading Edge and Inner to Inner Edge Methods in the Ultrasound Assessment of Maximum Abdominal Aortic Diameter.

    Science.gov (United States)

    Borgbjerg, Jens; Bøgsted, Martin; Lindholt, Jes S; Behr-Rasmussen, Carsten; Hørlyck, Arne; Frøkjær, Jens B

    2018-02-01

    Controversy exists regarding optimal caliper placement in ultrasound assessment of maximum abdominal aortic diameter. This study aimed primarily to determine reproducibility of caliper placement in relation to the aortic wall with the three principal methods: leading to leading edge (LTL), inner to inner edge (ITI), and outer to outer edge (OTO). The secondary aim was to assess the mean difference between the OTO, ITI, and LTL diameters and estimate the impact of using either of these methods on abdominal aortic aneurysm (AAA) prevalence in a screening program. Radiologists (n=18) assessed the maximum antero-posterior abdominal aortic diameter by completing repeated caliper placements with the OTO, LTL, and ITI methods on 50 still abdominal aortic images obtained from an AAA screening program. Inter-observer reproducibility was calculated as the limit of agreement with the mean (LoA), which represents expected deviation of a single observer from the mean of all observers. Intra-observer reproducibility was assessed averaging the LoA for each observer with their repeated measurements. Based on data from an AAA screening trial and the estimated mean differences between the three principal methods, AAA prevalence was estimated using each of the methods. The inter-observer LoA of the OTO, ITI, and LTL was 2.6, 1.9, and 1.9 mm, whereas the intra-observer LoA was 2.0, 1.6, and 1.5 mm, respectively. Mean differences of 5.0 mm were found between OTO and ITI measurements, 2.6 mm between OTO and LTL measurements, and 2.4 mm between LTL and ITI measurements. The prevalence of AAA almost doubled using OTO instead of ITI, while the difference between ITI and LTL was minor (3.3% vs. 4.0% AAA). The study shows superior reproducibility of LTL and ITI compared with the OTO method of caliper placement in ultrasound determination of maximum abdominal aortic diameter, and the choice of caliper placement method significantly affects the prevalence of AAAs in screening programs

  20. Lead-time reduction utilizing lean tools applied to healthcare: the inpatient pharmacy at a local hospital.

    Science.gov (United States)

    Al-Araidah, Omar; Momani, Amer; Khasawneh, Mohammad; Momani, Mohammed

    2010-01-01

    The healthcare arena, much like the manufacturing industry, benefits from many aspects of the Toyota lean principles. Lean thinking contributes to reducing or eliminating nonvalue-added time, money, and energy in healthcare. In this paper, we apply selected principles of lean management aiming at reducing the wasted time associated with drug dispensing at an inpatient pharmacy at a local hospital. Thorough investigation of the drug dispensing process revealed unnecessary complexities that contribute to delays in delivering medications to patients. We utilize DMAIC (Define, Measure, Analyze, Improve, Control) and 5S (Sort, Set-in-order, Shine, Standardize, Sustain) principles to identify and reduce wastes that contribute to increasing the lead-time in healthcare operations at the pharmacy understudy. The results obtained from the study revealed potential savings of > 45% in the drug dispensing cycle time.

  1. Assessment of Lead and Cadmium Levels in Frequently Used Cosmetic Products in Iran

    Science.gov (United States)

    Nourmoradi, H.; Foroghi, M.; Farhadkhani, M.; Vahid Dastjerdi, M.

    2013-01-01

    This study aims to investigate the content of lead and cadmium in most frequently used brands of cosmetic products (lipstick and eye shadow) in Iran. Fifty samples of lipstick (5 colors in 7 brands) and eye shadow (3 colors in 5 brands) were selected taken from large cosmetic stores in Isfahan (Iran) and lead and cadmium of them were analyzed. The results showed that the concentration of lead and cadmium in the lipsticks was within the range of 0.08–5.2 µg/g and 4.08–60.20 µg/g, respectively. The eye shadow samples had a lead level of 0.85–6.90 µg/g and a cadmium level of 1.54–55.59 µg/g. The content range of the heavy metals in the eye shadows was higher than that of the lipsticks. There was significant difference between the average of the lead content in the different brands of the lipsticks and eye shadows. Thus, the continuous use of these cosmetics can increase the absorption of heavy metals, especially Cd and Pb, in the body when swallowing lipsticks or through dermal cosmetic absorption. The effects of heavy metals such as lead can be harmful, especially for pregnant women and children. Therefore, effort must be made to inform the users and the general public about the harmful consequences of cosmetics. PMID:24174937

  2. Timing of Conduction Abnormalities Leading to Permanent Pacemaker Insertion After Transcatheter Aortic Valve Implantation-A Single-Centre Review.

    Science.gov (United States)

    Ozier, Daniel; Zivkovic, Nevena; Elbaz-Greener, Gabby; Singh, Sheldon M; Wijeysundera, Harindra C

    2017-12-01

    Transcatheter aortic valve implantation (TAVI) is the preferred alternative to traditional surgical aortic valve replacement; however, it remains expensive. One potential driver of cost is the need for postprocedural monitoring for conduction abnormalities after TAVI. Given the paucity of literature on the optimal length of monitoring, we aimed to determine when clinically significant conduction abnormalities leading to permanent pacemaker (PPM) insertion after TAVI were first identified. We identified all patients in the Sunnybrook Health Sciences Centre TAVI registry (Toronto, Canada) who underwent TAVI between 2009 and 2016, excluding those with pre-existing PPMs or those who underwent emergency open heart surgery. Through dedicated chart review, the timing and type of conduction abnormalities leading to PPM were recorded. Patients were divided according to the timing of conduction abnormality: during the procedure vs after the procedure. The overall PPM insertion rate was 15.6% (80 of 512 cases), with all but 1 patient receiving a PPM for class I indications. PPMs were inserted for complete heart block/high-grade atrioventricular block (91.3%), severe sinus node dysfunction (3.8%), and alternating bundle branch block (3.8%). Of these conduction abnormalities, 55.0% occurred during the procedure (intraprocedure; n = 44 patients). The mean time to the development of a conduction abnormality necessitating PPM was 1.2 days (interquartile range, 0-2 days), with 88.8% occurring within 72 hours of the procedure (n = 71 patients). In the entire TAVI cohort, leading to PPM. The majority of conduction abnormalities leading to PPM insertion after TAVI occur in the very early periprocedural period, suggesting that early mobilization and discharge will be safe from a conduction standpoint. Copyright © 2017 Canadian Cardiovascular Society. Published by Elsevier Inc. All rights reserved.

  3. Real-Time 12-Lead High-Frequency QRS Electrocardiography for Enhanced Detection of Myocardial Ischemia and Coronary Artery Disease

    Science.gov (United States)

    Schlegel, Todd T.; Kulecz, Walter B.; DePalma, Jude L.; Feiveson, Alan H.; Wilson, John S.; Rahman, M. Atiar; Bungo, Michael W.

    2004-01-01

    Several studies have shown that diminution of the high-frequency (HF; 150-250 Hz) components present within the central portion of the QRS complex of an electrocardiogram (ECG) is a more sensitive indicator for the presence of myocardial ischemia than are changes in the ST segments of the conventional low-frequency ECG. However, until now, no device has been capable of displaying, in real time on a beat-to-beat basis, changes in these HF QRS ECG components in a continuously monitored patient. Although several software programs have been designed to acquire the HF components over the entire QRS interval, such programs have involved laborious off-line calculations and postprocessing, limiting their clinical utility. We describe a personal computer-based ECG software program developed recently at the National Aeronautics and Space Administration (NASA) that acquires, analyzes, and displays HF QRS components in each of the 12 conventional ECG leads in real time. The system also updates these signals and their related derived parameters in real time on a beat-to-beat basis for any chosen monitoring period and simultaneously displays the diagnostic information from the conventional (low-frequency) 12-lead ECG. The real-time NASA HF QRS ECG software is being evaluated currently in multiple clinical settings in North America. We describe its potential usefulness in the diagnosis of myocardial ischemia and coronary artery disease.

  4. Microstructural Developments Leading to New Advanced High Strength Sheet Steels: A Historical Assessment of Critical Metallographic Observations

    Energy Technology Data Exchange (ETDEWEB)

    Matlock, David K [CSM/ASPPRC; Thomas, Larrin S [CSM/ASPPRC; Taylor, Mark D [CSM/ASPPRC; De Moor, Emmanuel [CSM/ASPPRC; Speer, John G [CSM/ASPPRC

    2015-08-03

    In the past 30+ years significant advancements have been made in the development of higher strength sheet steels with improved combinations of strength and ductility that have enabled important product improvements leading to safer, lighter weight, and more fuel efficient automobiles and in other applications. Properties of the primarily low carbon, low alloy steels are derived through careful control of time-temperature processing histories designed to produce multiphase ferritic based microstructures that include martensite and other constituents including retained austenite. The basis for these developments stems from the early work on dual-phase steels which was the subject of much interest. In response to industry needs, dual-phase steels have evolved as a unique class of advanced high strength sheet steels (AHSS) in which the thermal and mechanical processing histories have been specifically designed to produce constituent combinations for the purpose of simultaneously controlling strength and deformation behavior, i.e. stress-strain curve shapes. Improvements continue as enhanced dual-phase steels have recently been produced with finer microstructures, higher strengths, and better overall formability. Today, dual phase steels are the primary AHSS products used in vehicle manufacture, and several companies have indicated that the steels will remain as important design materials well into the future. In this presentation, fundamental results from the early work on dual-phase steels will be reviewed and assessed in light of recent steel developments. Specific contributions from industry/university cooperative research leading to product improvements will be highlighted. The historical perspective provided in the evolution of dual-phase steels represents a case-study that provides important framework and lessons to be incorporated in next generation AHSS products.

  5. Use of atomic absorption spectrometry in assessment of biomonitor plants for lead, cadmium and copper pollution.

    Science.gov (United States)

    Gokce, Kaya; Mehmet, Yaman

    2012-01-01

    Eleven plant species were collected from the vicinity of lead-battery plant in the city of Gaziantep, Turkey. Lead, cadmium and copper concentrations in the soil and leaves of plants were determined by atomic absorption spectrometry. Lead, Cd and Cu concentrations in the soil samples taken from battery area were found to be in the ranges of 304-602, 0.4-0.44 and 31-37 mg x kg(-1), respectively. Significantly increased lead concentration up to 2 750 mg x kg(-1) was found in the leaves of Eleagnus angustifolia L. plant. The lead concentrations in the other plant leaves taken from 50 m around battery factory followed the order Ailanthus altissima > Morus sp. > Juglans regia L. > Ficus carica L. > Cydonia oblonga Miller > Prunus x domestica L. The plants, Populus nigra L. , Eleagnus angustifolia L. and Salix sp. were found useful for Cd, and the plant, Eleagnus angusti folia L. for Pb, to be considered as potential biomonitor. Especially, leaves of trees and plants taken from the distance of 50 m from battery plant have relatively higher Pb concentrations. Therefore, people who and animals which live in this area and benefit from these soil and plants have vital risks.

  6. Properties of three-body decay functions derived with time-like jet calculus beyond leading order

    International Nuclear Information System (INIS)

    Sugiura, Tetsuya

    2002-01-01

    Three-body decay functions in time-like parton branching are calculated using the jet calculus to the next-to-leading logarithmic (NLL) order in perturbative quantum chromodynamics (QCD). The phase space contributions from each of the ladder diagrams and interference diagrams are presented. We correct part of the results for the three-body decay functions calculated previously by two groups. Employing our new results, the properties of the three-body decay functions in the regions of soft partons are examined numerically. Furthermore, we examine the contribution of the three-body decay functions modified by the restriction resulting from the kinematical boundary of the phase space for two-body decay in the parton shower model. This restriction leads to some problems for the parton shower model. For this reason, we propose a new restriction introduced by the kinematical boundary of the phase space for two-body decay. (author)

  7. Biological assessment of continuous exposure to tritium and lead in the rat

    International Nuclear Information System (INIS)

    Cahill, D.F.; Reiter, L.W.; Santolucito, J.A.; Rehnberg, G.I.; Ash, M.E.; Favor, M.J.; Bursian, S.J.; Wriht, J.F.; Laskey, J.W.

    1976-01-01

    A broad investigation of the effects of simultaneous exposure to two potentially synergistic environmental pollutants, tritiated water (HTO) and lead, was conducted. Sprague-Dawley rats were continuously exposed to HTO and/or Pb in drinking water from conception of the F 1 through adulthood of the F 2 generation. A l2-cell exposure matrix was used employing HTO activities calculated to provide approximately 3-300 mrad/d whole-body irradiation and Pb levels of 5 or 50 ppm in drinking water. Observations were made on the reproductive capacity of the F 1 generation and the effects of lifetime parental exposure to HTO and/or lead on the F 2 neonates. The effects of single and combined exposures on the development and function of the central nervous system, some brain catecholamine levels and electroencephalogram patterns were also examined in both generations. The results indicate that, in both generations, continuous HTO exposures as low as 3 mrad/d delayed development of righting reflexes in young rats; 30 mrad/d additionally depressed the spontaneous activity of adult male rats. Continuous exposure to 5 ppm lead produced similar effects on righting reflex development and adult spontaneous activity. The relative brain weight of F 2 neonates was decreased after lifetime parental exposure to 300 mrad/d or 5 and 50 ppm lead. Chronic lead exposure also appears to induce superovulation and increase preimplantation deaths in F 1 dams. Dose-effect responses to both HTO and lead were less than additive in their interactive effects on the parameters measured. (author)

  8. Environmental Assessment of Lead at Camp Edwards, Massachusetts, Small Arms Ranges

    Science.gov (United States)

    2007-08-01

    hydroxyapatite [Pb5(PO4)3(OH)], and lead oxyphosphate [Pb4O(PO4)2]. Lead phosphate minerals, in particular, are so sparingly soluble, thermodynamic...M ea n XR F Le ad Pr of ile R es ul ts (m g/ kg ) 1 -1 0 in ch es bg s M ea n XR F Le ad Pr of ile R es ul ts (m g/ kg ) 1 0- 20 in...ch es bg s M ea n XR F Le ad Pr of ile R es ul ts (m g/ kg ) 2 0- 30 in ch es

  9. PROJECTING POPULATION-LEVEL RESPONSE OF PURPLE SEA URCHINS TO LEAD CONTAMINATION FOR AN ESTUARINE ECOLOGICAL RISK ASSESSMENT

    Science.gov (United States)

    As part of an ecological risk assessment case study at the Portsmouth naval Shipyard (PNS), Kittery, Maine, USA, the population level effects of lead exposure to purple sea urchin, Arbacia punctulata, were investigated using a stage-classified matrix population model. The model d...

  10. Including a Service Learning Educational Research Project in a Biology Course-I: Assessing Community Awareness of Childhood Lead Poisoning

    Science.gov (United States)

    Abu-Shakra, Amal; Saliim, Eric

    2012-01-01

    A university course project was developed and implemented in a biology course, focusing on environmental problems, to assess community awareness of childhood lead poisoning. A set of 385 questionnaires was generated and distributed in an urban community in North Carolina, USA. The completed questionnaires were sorted first into yes and no sets…

  11. Self-vs.-Teammate Assessment of Leadership Competence: The Effects of Gender, Leadership Self-Efficacy, and Motivation to Lead

    Science.gov (United States)

    Rosch, David M.; Collier, Daniel A.; Zehr, Sarah M.

    2014-01-01

    A sample (N = 81) of undergraduates participating in a semester-long team-project engineering course completed assessments of their leadership competence, motivation to lead, and leadership self-efficacy, as well as the leadership competence of their peers who served within their durable teams. Results indicated that peers scored students lower…

  12. Time-variant reliability assessment through equivalent stochastic process transformation

    International Nuclear Information System (INIS)

    Wang, Zequn; Chen, Wei

    2016-01-01

    Time-variant reliability measures the probability that an engineering system successfully performs intended functions over a certain period of time under various sources of uncertainty. In practice, it is computationally prohibitive to propagate uncertainty in time-variant reliability assessment based on expensive or complex numerical models. This paper presents an equivalent stochastic process transformation approach for cost-effective prediction of reliability deterioration over the life cycle of an engineering system. To reduce the high dimensionality, a time-independent reliability model is developed by translating random processes and time parameters into random parameters in order to equivalently cover all potential failures that may occur during the time interval of interest. With the time-independent reliability model, an instantaneous failure surface is attained by using a Kriging-based surrogate model to identify all potential failure events. To enhance the efficacy of failure surface identification, a maximum confidence enhancement method is utilized to update the Kriging model sequentially. Then, the time-variant reliability is approximated using Monte Carlo simulations of the Kriging model where system failures over a time interval are predicted by the instantaneous failure surface. The results of two case studies demonstrate that the proposed approach is able to accurately predict the time evolution of system reliability while requiring much less computational efforts compared with the existing analytical approach. - Highlights: • Developed a new approach for time-variant reliability analysis. • Proposed a novel stochastic process transformation procedure to reduce the dimensionality. • Employed Kriging models with confidence-based adaptive sampling scheme to enhance computational efficiency. • The approach is effective for handling random process in time-variant reliability analysis. • Two case studies are used to demonstrate the efficacy

  13. Pain assessment in time to get pain treatment on time – patients’ perspective of time during pain assessment after spine surgery

    DEFF Research Database (Denmark)

    Kaptain, Kirsten; Bregnballe, Vibeke; Dreyer, Pia

    their pain. Furthermore, patients experienced that the nurses kept an eye on them by frequently contact and by being available for questions about pain. Conclusion: Pain experiences changes rapidly and therefore it is important to assess pain in time. Accurate pain assessment is essential to achieve...

  14. A Comparative Assessment of Serum Vitamin C and Serum Lead Among Periodontitis and Diabetic Patient

    Directory of Open Access Journals (Sweden)

    Shetty Akshatha

    2017-09-01

    Full Text Available Background and Aims: Pre and post-operative nutritional status are not often tested on a consistent basis when patients are analyzed and diagnosed with Type 2 Diabetes Mellitus (T2DM or have chronic periodontitis. Thus, this study pursues to evaluate the predictive value of serum vitamin C and lead levels in this population at baseline and after periodontal treatment.

  15. Updated assessment of critical loads of lead and cadmium for European forest soils

    NARCIS (Netherlands)

    Reinds, G.J.; Vries, de W.; Groenenberg, J.E.

    2002-01-01

    At its 20th session the Working Group on Effects (WGE) of the Convention on Long-range Transboundary Air Pollution of the United Nations Economic Commission for Europe (UNECECLRTAP), noted the need to further develop and test the methodology for mapping critical loads for cadmium and lead. To this

  16. Privacy Impact Assessment for the Lead-based Paint System of Records

    Science.gov (United States)

    The Lead-based Paint System of Records collects personally identifiable information, test scores, and submitted fees. Learn how this data is collected, how it will be used, access to the data, the purpose of data collection, and record retention policies.

  17. Assessing the scientific relevance of a single publication over time

    Directory of Open Access Journals (Sweden)

    Philipp A. Bloching

    2013-09-01

    Full Text Available Quantitatively assessing the scientific relevance of a research paper is challenging for two reasons. Firstly, scientific relevance may change over time, and secondly, it is unclear how to evaluate a recently published paper. The temporally averaged paper-specific impact factor is defined as the yearly average of citations to the paper until now including bonus citations equal to the journal impact factor in the publication year. This new measure subsequently allows relevance rankings and annual updates of all (i.e. both recent and older scientific papers of a department, or even a whole scientific field, on a more objective basis. It can also be used to assess both the average and overall time-dependent scientific relevance of researchers in a specific department or scientific field.

  18. Multivariate statistical assessment of heavy metal pollution sources of groundwater around a lead and zinc plant

    Directory of Open Access Journals (Sweden)

    Zamani Abbas Ali

    2012-12-01

    Full Text Available Abstract The contamination of groundwater by heavy metal ions around a lead and zinc plant has been studied. As a case study groundwater contamination in Bonab Industrial Estate (Zanjan-Iran for iron, cobalt, nickel, copper, zinc, cadmium and lead content was investigated using differential pulse polarography (DPP. Although, cobalt, copper and zinc were found correspondingly in 47.8%, 100.0%, and 100.0% of the samples, they did not contain these metals above their maximum contaminant levels (MCLs. Cadmium was detected in 65.2% of the samples and 17.4% of them were polluted by this metal. All samples contained detectable levels of lead and iron with 8.7% and 13.0% of the samples higher than their MCLs. Nickel was also found in 78.3% of the samples, out of which 8.7% were polluted. In general, the results revealed the contamination of groundwater sources in the studied zone. The higher health risks are related to lead, nickel, and cadmium ions. Multivariate statistical techniques were applied for interpreting the experimental data and giving a description for the sources. The data analysis showed correlations and similarities between investigated heavy metals and helps to classify these ion groups. Cluster analysis identified five clusters among the studied heavy metals. Cluster 1 consisted of Pb, Cu, and cluster 3 included Cd, Fe; also each of the elements Zn, Co and Ni was located in groups with single member. The same results were obtained by factor analysis. Statistical investigations revealed that anthropogenic factors and notably lead and zinc plant and pedo-geochemical pollution sources are influencing water quality in the studied area.

  19. Multivariate statistical assessment of heavy metal pollution sources of groundwater around a lead and zinc plant.

    Science.gov (United States)

    Zamani, Abbas Ali; Yaftian, Mohammad Reza; Parizanganeh, Abdolhossein

    2012-12-17

    The contamination of groundwater by heavy metal ions around a lead and zinc plant has been studied. As a case study groundwater contamination in Bonab Industrial Estate (Zanjan-Iran) for iron, cobalt, nickel, copper, zinc, cadmium and lead content was investigated using differential pulse polarography (DPP). Although, cobalt, copper and zinc were found correspondingly in 47.8%, 100.0%, and 100.0% of the samples, they did not contain these metals above their maximum contaminant levels (MCLs). Cadmium was detected in 65.2% of the samples and 17.4% of them were polluted by this metal. All samples contained detectable levels of lead and iron with 8.7% and 13.0% of the samples higher than their MCLs. Nickel was also found in 78.3% of the samples, out of which 8.7% were polluted. In general, the results revealed the contamination of groundwater sources in the studied zone. The higher health risks are related to lead, nickel, and cadmium ions. Multivariate statistical techniques were applied for interpreting the experimental data and giving a description for the sources. The data analysis showed correlations and similarities between investigated heavy metals and helps to classify these ion groups. Cluster analysis identified five clusters among the studied heavy metals. Cluster 1 consisted of Pb, Cu, and cluster 3 included Cd, Fe; also each of the elements Zn, Co and Ni was located in groups with single member. The same results were obtained by factor analysis. Statistical investigations revealed that anthropogenic factors and notably lead and zinc plant and pedo-geochemical pollution sources are influencing water quality in the studied area.

  20. Lead exposure from soil in Peruvian mining towns: a national assessment supported by two contrasting examples.

    Science.gov (United States)

    van Geen, Alexander; Bravo, Carolina; Gil, Vladimir; Sherpa, Shaky; Jack, Darby

    2012-12-01

    To estimate the population of Peru living in the vicinity of active or former mining operations that could be exposed to lead from contaminated soil. Geographic coordinates were compiled for 113 active mines, 138 ore processing plants and 3 smelters, as well as 7743 former mining sites. The population living within 5 km of these sites was calculated from census data for 2000. In addition, the lead content of soil in the historic mining town of Cerro de Pasco and around a recent mine and ore processing plant near the city of Huaral was mapped in 2009 using a hand-held X-ray fluorescence analyser. Spatial analysis indicated that 1.6 million people in Peru could be living within 5 km of an active or former mining operation. Two thirds of the population potentially exposed was accounted for by 29 clusters of mining operations, each with a population of over 10 000 each. These clusters included 112 active and 3438 former mining operations. Soil lead levels exceeded 1200 mg/kg, a reference standard for residential soil, in 35 of 74 sites tested in Cerro de Pasco but in only 4 of 47 sites tested around the newer operations near Huaral. Soil contamination with lead is likely to be extensive in Peruvian mining towns but the level of contamination is spatially far from uniform. Childhood exposure by soil ingestion could be substantially reduced by mapping soil lead levels, making this information public and encouraging local communities to isolate contaminated areas from children.

  1. Assessment of and proposal for a mechanistic interpretation of the SCC of high nickel alloys in lead-containing environments

    International Nuclear Information System (INIS)

    Staehle, R.W.

    2002-01-01

    The SCC of Alloys 600 and 690 in lead-containing solutions, 'lead stress corrosion cracking' (PbSCC) is quite aggressive on tubing in conditions of operation of steam generators (SG) in pressurized water reactors (PWR). Lead dissolved in water can produce PbSCC at concentrations of Pb as low as 0.1 ppm in these alloys. PbSCC is perhaps the most generally aggressive of the environmental species that occur in SGs. This discussion considers the occurrence of Pb in SGs and the PbSCC that can result. The dependencies of PbSCC on the variables of pH, potential, species, alloy composition, alloy structure, temperature and stress are reviewed. Also, important features of the mechanism of PbSCC are assessed. The most significant question related to PbSCC is why more is not occurring in view of the low thresholds for the PbSCC and the ubiquity of the Pb. While there are usually no common specific sources for Pb in most secondary systems, Pb concentrates on surfaces of tubing efficiently over long times. Regardless, it appears that extensive PbSCC does not occur because it is immobilized by forming stable compounds with other species such as sulfur, carbon, phosphorous and silica. Pb is also immobilized by forming stable adsorbed states with oxides such as magnetite and hematite. The possibility of releasing Pb to produce PbSCC increases as water chemistry produces more pure systems and as chemical cleaning is used. Contrary to the common assumption that PbSCC is TGSCC, that of Alloy 600MA is generally IGSCC; only the sensitized (SN), stress relieved (SR) and thermally treated (TT) conditions of Alloys 600 and 690 sustain TGSCC in Pb-containing solutions. In view of the prevailing IGSCC produced by Pb in MA materials, the possibility of all IGSCC in SGs being due to Pb should be considered where crevice environments are in the nominally neutral range. TGSCC that is observed in SGs can be produced by other, although not widely appreciated, environments. The mechanism of Pb

  2. Responsive and resilient supply chain network design under operational and disruption risks with delivery lead-time sensitive customers

    DEFF Research Database (Denmark)

    Fattahi, Mohammad; Govindan, Kannan; Keyvanshokooh, Esmaeil

    2017-01-01

    We address a multi-period supply chain (SC) network design where demands of customers depend on facilities serving them based on their delivery lead-times. Potential customer demands are stochastic, and facilities’ capacity varies randomly because of possible disruptions. Accordingly, we develop...... a multi-stage stochastic program, and model disruptions’ effect on facilities’ capacity. The SC responsiveness risk is limited and, to obtain a resilient network, both mitigation and contingency strategies are exploited. Computational results on a real-life case study and randomly generated problem...... instances demonstrate the model's applicability, risk-measurement policies’ performance, and the influence of mitigation and contingency strategies on SC's resiliency....

  3. Reevaluation of time spent indoors used for exposure dose assessment

    International Nuclear Information System (INIS)

    Hirose, Katsumi; Fujimoto, Kenzo

    2016-01-01

    A time spent indoors of sixteen hours per day (indoor occupancy factor: 0.67) has been used to assess the radiation dose of residents who spend daily life in the area contaminated due to the nuclear accident in Japan. However, much longer time is considered to be spent indoors for recent modern life. United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) has been used an indoor occupancy factor of 0.8 since 1977 and a few reports suggested much higher indoor occupancy factors. Therefore it is important to reevaluate the indoor occupancy factor using current available survey data in Japan, such as 'NHK 2010 National Time Use Survey' and 'Survey on Time Use and Leisure Activities' of Statistics Bureau with certain assumption of time spent indoors in each daily activity. The total time spent indoors in a day is calculated to be 20.2 hours and its indoor occupancy factor is 0.84. Much lower indoor occupancy factors were derived from the survey data by Statistics Bureau for 10 to 14 and 15 to 19 years old groups and farmers who spend most of their time outdoors although present estimated indoor occupancy factor of 0.84 is still lower than those found in some of the relevant reports. A rounded indoor occupancy factor of 0.80 might be the appropriate conservative reference value to be used for the dose estimation of people who live in radioactively contaminated areas and for other relevant purposes of exposure assessment, taken into consideration the present results and values reported in United States Environmental Protection Agency (US EPA) and UNSCEAR. (author)

  4. Assessment of lead tellurite glass for immobilizing electrochemical salt wastes from used nuclear fuel reprocessing

    Energy Technology Data Exchange (ETDEWEB)

    Riley, Brian J.; Kroll, Jared O.; Peterson, Jacob A.; Pierce, David A.; Ebert, William L.; Williams, Benjamin D.; Snyder, Michelle M. V.; Frank, Steven M.; George, Jaime L.; Kruska, Karen

    2017-11-01

    This paper provides an overview of research evaluating the use of lead tellurite glass as a waste form for salt wastes from electrochemical reprocessing of used nuclear fuel. The efficacy of using lead tellurite glass to immobilize three different salt compositions was evaluated: a LiCl-Li2O oxide reduction salt containing fission products from oxide fuel, a LiCl-KCl eutectic salt containing fission products from metallic fuel, and SrCl2. Physical and chemical properties of glasses made with these salts were characterized with X-ray diffraction, bulk density measurements, differential thermal analysis, chemical durability tests, scanning and transmission electron microscopies, and energy-dispersive X-ray spectroscopy. These glasses were found to accommodate high salt concentrations and have high densities, but further development is needed to improve chemical durability. (C) 2017 Published by Elsevier B.V.

  5. A geometric process model for M/PH(M/PH)/1/K queue with new service machine procurement lead time

    Science.gov (United States)

    Yu, Miaomiao; Tang, Yinghui; Fu, Yonghong

    2013-06-01

    In this article, we consider a geometric process model for M/PH(M/PH)/1/K queue with new service machine procurement lead time. A maintenance policy (N - 1, N) based on the number of failures of the service machine is introduced into the system. Assuming that a failed service machine after repair will not be 'as good as new', and the spare service machine for replacement is only available by an order. More specifically, we suppose that the procurement lead time for delivering the spare service machine follows a phase-type (PH) distribution. Under such assumptions, we apply the matrix-analytic method to develop the steady state probabilities of the system, and then we obtain some system performance measures. Finally, employing an important Lemma, the explicit expression of the long-run average cost rate for the service machine is derived, and the direct search method is also implemented to determine the optimal value of N for minimising the average cost rate.

  6. Proposal of lead time reduction in the thermoelectric products line of a small company in the State of Sao Paulo

    Directory of Open Access Journals (Sweden)

    Fernanda Veríssimo Soulé

    2016-03-01

    Full Text Available Quick Response Manufacturing (QRM is a way manufacturing companies may increase their flexibility. Manufacturing flexibility is a key to differentiation and enhancement of competitiveness. There is few empirical research on the topic of how small and medium-sized enterprises (SME may benefit from QRM, what may impact the appropriation of this approach by these important actors of our economy. This article aims to present the results of a project which applied QRM to reduce the lead time of a small company located in the state of Sao Paulo. It was proposed to a balance the throughputs of slow operations, reducing 50% of production batches; b implement cellular manufacturing and improvements in the management of Work In Process, using the POLCA system and visual management; c implement an integrated sales and operations planning (S&OP and rules for prioritization of orders. It was identified that the proposal would generate a lead time reduction from 39 to 21.3 days and a decrease of at least 51% in the raw materials stock costs. During the research, the following conclusions could be drawn: a problems in management, investment capacity and relationship with suppliers are frequent in family-owned SMEs; b QRM approach can be adapted to work within this environment; c the knowledge developed in academia can be an important tool to help family-owned SMEs to supplant these obstacles.

  7. Development of a real-time radiological dose assessment system

    Energy Technology Data Exchange (ETDEWEB)

    Han, Moon Hee; Lee, Young Bok; Kim, Eun Han; Suh, Kyung Suk; Hwang, Won Tae; Choi, Young Gil

    1997-07-01

    A radiological dose assessment system named FADAS has been developed. This system is necessary to estimated the radiological consequences against a nuclear accident. Mass-consistent wind field module was adopted for the generation of wind field over the whole domain using the several measured wind data. Random-walk dispersion module is used for the calculation of the distribution of radionuclides in the atmosphere. And volume-equivalent numerical integration method has been developed for the assessment of external gamma exposure given from a randomly distributed radioactive materials and a dose data library has been made for rapid calculation. Field tracer experiments have been carried out for the purpose of analyzing the site-specific meteorological characteristics and increasing the accuracy of wind field generation and atmospheric dispersion module of FADAS. At first, field tracer experiment was carried out over flat terrain covered with rice fields using the gas samplers which were designed and manufactured by the staffs of KAERI. The sampled gas was analyzed using gas chromatograph. SODAR and airsonde were used to measure the upper wind. Korean emergency preparedness system CARE was integrated at Kori 4 nuclear power plants in 1995. One of the main functions of CARE is to estimate the radiological dose. The developed real-time dose assessment system FADAS was adopted in CARE as a tool for the radiological dose assessment. (author). 79 refs., 52 tabs., 94 figs.

  8. Time frames and uncertainty in assessment of geoscientific environment

    International Nuclear Information System (INIS)

    Kusunose, Kinichiro; Koide, Hitoshi

    2001-01-01

    Second Progress Report on Research and Development for the Geological Disposal of high-level radioactive waste (HLW) in Japan was published in 2000 by Japan Nuclear Cycle Development Institute. The issue presents basic technical feasibility of safe HLW disposal on Japan. The issue, however, lacks discussion about realistic time frame for geological stability assessment, and treating of instability in geoscientific models, because candidate repository sites have not yet selected in Japan. This paper present short conceptional discussion of the time frames and instability in geoscientific models and propose some time frames and instability treating process. Methods of geological prediction are classified into seven groups: (1) Prediction by extrapolation, (2) Prediction by analogy, (3) Prediction by probability, (4) Prediction by experiment, (5) Prediction by conceptual model, (6) Prediction by numerical simulation, and (7) Prediction by safety assessment model. Geologic future prediction should be cross-checked by several different methods. However, only geological evidence from the earth's history of nearly five billion years can verify long-range predictions for subterranean containment of waste which are usually based on short-range experiments and numerical modeling. On the geologically unstable Japanese archipelago, Japan is making extensive efforts for prediction of earthquakes and volcanic eruptions to reduce geological hazards. Long-range geological prediction is investigated for safe disposal of nuclear waste and for subterranean sequestration of CO 2 . (author)

  9. Real-time risk assessment of operational events

    International Nuclear Information System (INIS)

    Perryman, L.J.; Foster, N.A.S.; Nicholls, D.R.; Grobbelaar, J.F.

    1996-01-01

    Probabilistic risk assessment (PRA) has always been fundamental to the licensing process of Koeberg nuclear power station. Furthermore, over the past 8 years PRA has assisted in many areas of operation. One of these areas is the real-time assessment of abnormal operating events. Over the years, considerable experience has been gained in using PRA to improve plant safety and performance. This paper presents some of the insights obtained in using PRA in such a dynamic role and demonstrates that, by developing and using the plant-specific 'living' PRA, considerable safety and financial gains can be obtained. These insights specifically concern the prerequisites before optimal use of a plant-specific 'living' PRA can be made. Finally, examples are presented of occurrences when PRA was used to improve plant safety and performance. These examples serve to demonstrate the advantages that can be obtained if sufficient resources are placed at the disposal of the PRA team. (orig.)

  10. Environmental health risk assessment of ambient lead levels in Lisbon, Portugal: A full chain study approach

    DEFF Research Database (Denmark)

    Casimiro, E.; Philippe Ciffroy, P.; Serpa, P.

    2011-01-01

    to calculate the Pb levels in the various body systems. Our results showed a low health risk from Pb exposures. It also identified that ingestion of leafy vegetables (i.e. lettuce, cabbage, and spinach) and fruits contribute the most to total Pb blood levels. This full chain assessment approach of the 2FUN...

  11. Fluorometric detection of nitroaromatics by fluorescent lead complexes: A spectroscopic assessment of detection mechanism

    Science.gov (United States)

    Chattopadhyay, Tanmay; Chatterjee, Sourav; Majumder, Ishani; Ghosh, Soumen; Yoon, Sangee; Sim, Eunji

    2018-04-01

    Three Schiff base ligands such as 2-[(2-Hydroxy-3-methoxy-benzylidene)-amino]-2-hydroxymethyl-propane-1,3-diol (HL1), 2-[(2-Hydroxy-benzylidene)-amino]-2-hydroxymethyl-propane-1,3-diol (HL2), 2-[(3,5-Dichloro-2-hydroxy-benzylidene)-amino]-2-hydroxymethyl-propane-1,3-diol (HL3) have been synthesized by condensation of aldehydes (such as 3,5-Dichloro-2-hydroxy benzaldehyde, 2-Hydroxy-benzaldehyde, and 2-Hydroxy-3-methoxy-benzaldehyde) with Tris-(hydroxymethyl)amino methane and characterized by IR, UV-vis and 1H NMR spectroscopy. Then all these three ligands have been used to prepare Pb(II) complexes by reaction with lead(II) acetate tri-hydrate in methanol. In view of analytical and spectral (IR, UV-vis and Mass) studies, it has been concluded that, except HL2, other two ligands form 1:1 metal complexes (1 and 3) with lead. Between two complexes, complex 3 is highly fluorescent and this property has been used to identify the pollutant nitroaromatics. Finally, the quenching mechanism has been established by means of spectroscopic investigation.

  12. DNA damage and repair assessed by comet assay in workers exposed to lead in a battery recycling.

    Directory of Open Access Journals (Sweden)

    Mahara Valverde

    2015-05-01

    In addition to these findings, DNA damage determined by comet assay was sensible to reflect lead exposure levels related to specific activities inside this factory. Human biomonitoring studies through comet assay could be robust when additional biomarkers are determined at time.

  13. Assessing Coupling Dynamics from an Ensemble of Time Series

    Directory of Open Access Journals (Sweden)

    Germán Gómez-Herrero

    2015-04-01

    Full Text Available Finding interdependency relations between time series provides valuable knowledge about the processes that generated the signals. Information theory sets a natural framework for important classes of statistical dependencies. However, a reliable estimation from information-theoretic functionals is hampered when the dependency to be assessed is brief or evolves in time. Here, we show that these limitations can be partly alleviated when we have access to an ensemble of independent repetitions of the time series. In particular, we gear a data-efficient estimator of probability densities to make use of the full structure of trial-based measures. By doing so, we can obtain time-resolved estimates for a family of entropy combinations (including mutual information, transfer entropy and their conditional counterparts, which are more accurate than the simple average of individual estimates over trials. We show with simulated and real data generated by coupled electronic circuits that the proposed approach allows one to recover the time-resolved dynamics of the coupling between different subsystems.

  14. Probabilistic inference under time pressure leads to a cortical-to-subcortical shift in decision evidence integration.

    Science.gov (United States)

    Oh-Descher, Hanna; Beck, Jeffrey M; Ferrari, Silvia; Sommer, Marc A; Egner, Tobias

    2017-11-15

    Real-life decision-making often involves combining multiple probabilistic sources of information under finite time and cognitive resources. To mitigate these pressures, people "satisfice", foregoing a full evaluation of all available evidence to focus on a subset of cues that allow for fast and "good-enough" decisions. Although this form of decision-making likely mediates many of our everyday choices, very little is known about the way in which the neural encoding of cue information changes when we satisfice under time pressure. Here, we combined human functional magnetic resonance imaging (fMRI) with a probabilistic classification task to characterize neural substrates of multi-cue decision-making under low (1500 ms) and high (500 ms) time pressure. Using variational Bayesian inference, we analyzed participants' choices to track and quantify cue usage under each experimental condition, which was then applied to model the fMRI data. Under low time pressure, participants performed near-optimally, appropriately integrating all available cues to guide choices. Both cortical (prefrontal and parietal cortex) and subcortical (hippocampal and striatal) regions encoded individual cue weights, and activity linearly tracked trial-by-trial variations in the amount of evidence and decision uncertainty. Under increased time pressure, participants adaptively shifted to using a satisficing strategy by discounting the least informative cue in their decision process. This strategic change in decision-making was associated with an increased involvement of the dopaminergic midbrain, striatum, thalamus, and cerebellum in representing and integrating cue values. We conclude that satisficing the probabilistic inference process under time pressure leads to a cortical-to-subcortical shift in the neural drivers of decisions. Copyright © 2017 Elsevier Inc. All rights reserved.

  15. Heart Surgery Waiting Time: Assessing the Effectiveness of an Action.

    Science.gov (United States)

    Badakhshan, Abbas; Arab, Mohammad; Gholipour, Mahin; Behnampour, Naser; Saleki, Saeid

    2015-08-01

    Waiting time is an index assessing patient satisfaction, managerial effectiveness and horizontal equity in providing health care. Although heart surgery centers establishment is attractive for politicians. They are always faced with the question of to what extent they solve patient's problems. The objective of this study was to evaluate factors influencing waiting time in patients of heart surgery centers, and to make recommendations for health-care policy-makers for reducing waiting time and increasing the quality of services from this perspective. This cross-sectional study was performed in 2013. After searching articles on PubMed, Elsevier, Google Scholar, Ovid, Magiran, IranMedex, and SID, a list of several criteria, which relate to waiting time, was provided. Afterwards, the data on waiting time were collected by a researcher-structured checklist from 156 hospitalized patients. The data were analyzed by SPSS 16. The Kolmogorov Smirnov and Shapiro tests were used for determination of normality. Due to the non-normal distribution, non-parametric tests, such as Kruskal-Wallis and Mann-Whitney were chosen for reporting significance. Parametric tests also used reporting medians. Among the studied variables, just economic status had a significant relation with waiting time (P = 0.37). Fifty percent of participants had diabetes, whereas this estimate was 43.58% for high blood pressure. As the cause of delay, 28.2% of patients reported financial problems, 18.6% personal problem and 13.5% a delay in providing equipment by the hospital. It seems the studied hospital should review its waiting time arrangements and detach them, as far as possible, from subjective and personal (specialists) decisions. On the other hand, ministries of health and insurance companies should consider more financial support. It is also recommend that hospitals should arrange preoperational psychiatric consultation for increasing patients' emotionally readiness.

  16. Solar Atmosphere to Earth's Surface: Long Lead Time dB/dt Predictions with the Space Weather Modeling Framework

    Science.gov (United States)

    Welling, D. T.; Manchester, W.; Savani, N.; Sokolov, I.; van der Holst, B.; Jin, M.; Toth, G.; Liemohn, M. W.; Gombosi, T. I.

    2017-12-01

    The future of space weather prediction depends on the community's ability to predict L1 values from observations of the solar atmosphere, which can yield hours of lead time. While both empirical and physics-based L1 forecast methods exist, it is not yet known if this nascent capability can translate to skilled dB/dt forecasts at the Earth's surface. This paper shows results for the first forecast-quality, solar-atmosphere-to-Earth's-surface dB/dt predictions. Two methods are used to predict solar wind and IMF conditions at L1 for several real-world coronal mass ejection events. The first method is an empirical and observationally based system to estimate the plasma characteristics. The magnetic field predictions are based on the Bz4Cast system which assumes that the CME has a cylindrical flux rope geometry locally around Earth's trajectory. The remaining plasma parameters of density, temperature and velocity are estimated from white-light coronagraphs via a variety of triangulation methods and forward based modelling. The second is a first-principles-based approach that combines the Eruptive Event Generator using Gibson-Low configuration (EEGGL) model with the Alfven Wave Solar Model (AWSoM). EEGGL specifies parameters for the Gibson-Low flux rope such that it erupts, driving a CME in the coronal model that reproduces coronagraph observations and propagates to 1AU. The resulting solar wind predictions are used to drive the operational Space Weather Modeling Framework (SWMF) for geospace. Following the configuration used by NOAA's Space Weather Prediction Center, this setup couples the BATS-R-US global magnetohydromagnetic model to the Rice Convection Model (RCM) ring current model and a height-integrated ionosphere electrodynamics model. The long lead time predictions of dB/dt are compared to model results that are driven by L1 solar wind observations. Both are compared to real-world observations from surface magnetometers at a variety of geomagnetic latitudes

  17. Environmental Assessment for the off-site commercial cleaning of lead and asbestos contaminated laundry from the Savannah River Site

    International Nuclear Information System (INIS)

    1995-12-01

    This Environmental Assessment (EA) has been prepared by the Department of Energy (DOE) to assess the potential environmental impacts of off-site commercial cleaning of lead and asbestos contaminated laundry generated at the Savannah River Site (SRS), located near Aiken, South Carolina. The proposed action constitutes an addition to the already-implemented action of sending controlled and routine SRS laundry to an off-site commercial facility for cleaning. This already-implemented action was evaluated in a previous EA (i.e., DOE/EA-0990; DOE, 1994) prepared under the National Environmental Policy Act of 1969 (NEPA)

  18. Assessing lead thresholds for phytotoxicity and potential dietary toxicity in selected vegetable crops.

    Science.gov (United States)

    Hong, C L; Jia, Y B; Yang, X E; He, Z L; Stoffella, P J

    2008-04-01

    Lead tolerance and accumulation in shoots and edible parts varied with crop species and soil type. The critical Pb concentrations at 10% yield reduction were 24.71, 28.25, and 0.567 mg kg(-1) for pakchoi, celery, and hot pepper, respectively under hydroponic conditions, whereas were 13.1, 3.83, 0.734 mg kg(-1) grown in the Inceptisol and 31.7, 30.0, 0.854 mg kg(-1) in the Alluvial soil, respectively. Based on the threshold of human dietary toxicity for Pb, the critical levels of soil available Pb for pakchoi, celery, and hot pepper were 5.07, 8.06, and 0.48 mg kg(-1) for the Inceptisol, and 1.38, 1.47, and 0.162 mg kg(-1) for the Alluvial soil, respectively. Similarly, the total soil Pb thresholds were different from vegetable species and soil types.

  19. Considerations on assessment of different time depending models adequacy

    International Nuclear Information System (INIS)

    Constantinescu, C.

    2015-01-01

    The operating period of nuclear power plants can be prolonged if it can be shown that their safety has remained on a high level, and for this, it is necessary to estimate how the aged systems, structures and components (SSCs) influence the NPP reliability and safety. To emphasize the ageing aspects the case study presented in this paper will assess different time depending models for rate of occurrence of failures with the goal to obtain the best fitting model. A sensitivity analysis for the impact of burn-in failures was performed to improve the result of the goodness of fit test. Based on the analysis results, a conclusion about the existence or the absence of an ageing trend could be developed. A sensitivity analysis regarding of the reliability parameters was performed, and the results were used to observe the impact over the time-dependent rate of occurrence of failures. (authors)

  20. Comparative assessment of the effects of salinomycin and monensin on the biodistribution of lead and some essential metal ions in mice, subjected to subacute lead intoxication.

    Science.gov (United States)

    Ivanova, Juliana; Gluhcheva, Yordanka; Dimova, Donika; Pavlova, Ekaterina; Arpadjan, Sonja

    2016-01-01

    In this study, we present a comparative assessment of the effects of two polyether ionophorous antibiotics (monensin and salinomycin) on the concentrations of lead (Pb), cooper (Cu), zinc (Zn) and iron (Fe) in the kidneys, spleen, liver and brain of Pb-intoxicated animals. Our data demonstrated that the intoxication of ICR male mice with Pb salt resulted in a significant accumulation of Pb in all studied organs of the mice compared to the untreated control animals. The biodistribution of the toxic metal was in the order kidneys>spleen>liver>brain. The treatment of the Pb-intoxicated animals with tetraethylammonium salts of monensic and salinomycinic acids significantly decreased the concentration of the toxic metal ion compared to the toxic control. The effect varied in the interval 38% (for kidneys) to 52% (for brain) compared to the toxic control group (Pb). The tetraethylammonium salt of salinomycinic acid was more effective in reducing the Pb concentration in the brain of the Pb-treated mice compared to monensin. Pb-intoxication did not affect significantly the Zn endogenous concentration compared to the normal values. The treatment of ICR male mice with Pb-salt decreased the Cu concentration in the spleen and increased the Cu concentration in the liver compared to the untreated control animals. The detoxification of the Pb-intoxicated mice with tetraethylammonium salts of salinomycinic and monensic acids restored the Cu concentration in the spleen, but did not affect the Cu levels in the liver. The Pb-intoxication of the ICR mice resulted in a significant decrease of the Fe-concentration in the spleen and liver compared to the untreated control animals. The administration of the tetraethylammonium salts of salinomycinic and monensic acids to the Pb-treated animals restored the levels of Fe in both organs. Copyright © 2015 Elsevier GmbH. All rights reserved.

  1. Indirect human exposure assessment of airborne lead deposited on soil via a simplified fate and speciation modelling approach.

    Science.gov (United States)

    Pizzol, Massimo; Bulle, Cécile; Thomsen, Marianne

    2012-04-01

    In order to estimate the total exposure to the lead emissions from a municipal waste combustion plant in Denmark, the indirect pathway via ingestion of lead deposited on soil has to be quantified. Multi-media fate models developed for both Risk Assessment (RA) and Life Cycle Assessment (LCA) can be used for this purpose, but present high uncertainties in the assessment of metal's fate. More sophisticated and metal-specific geochemical models exist, that could lower the uncertainties by e.g. accounting for metal speciation, but they require a large amount of data and are unpractical to combine broadly with other fate and dispersion models. In this study, a Simplified Fate & Speciation Model (SFSM) is presented, that is based on the parsimony principle: "as simple as possible, as complex as needed", and that can be used for indirect human exposure assessment in different context like RA and regionalized LCA. SFSM couples traditional multi-media mass balances with empirical speciation models in a tool that has a simple theoretical framework and that is not data-intensive. The model calculates total concentration, dissolved concentration, and free ion activity of Cd, Cu, Ni, Pb and Zn in different soil layers, after accounting for metal deposition and dispersion. The model is tested for these five metals by using data from peer reviewed literature. Results show good accordance between measured and calculated values (factor of 3). The model is used to predict the human exposure via soil to lead initially emitted into air by the waste combustion plant and both the lead cumulative exposure and intake fraction are calculated. Copyright © 2012 Elsevier B.V. All rights reserved.

  2. Picture archiving and communication systems lead to sustained improvements in reporting times and productivity: results of a 5-year audit

    Energy Technology Data Exchange (ETDEWEB)

    Mackinnon, A.D.; Billington, R.A.; Adam, E.J.; Dundas, D.D. [Department of Radiology, St Georges Hospital NHS Trust, London (United Kingdom); Patel, U. [Department of Radiology, St Georges Hospital NHS Trust, London (United Kingdom)], E-mail: Uday.Patel@stgeorges.nhs.uk

    2008-07-15

    Aim: To evaluate the impact of picture archiving and communications systems (PACS) on reporting times and productivity in a large teaching hospital. Materials and methods: Reporting time, defined as the time taken from patient registration to report availability, and productivity, defined as the number of reports issued per whole time equivalent (WTE) radiologist per month, were studied for 2 years pre- and 3 years post-PACS installation. Mean reporting time was calculated for plain radiographs and specialist radiology techniques [computed tomography (CT), magnetic resonance imaging (MRI), ultrasound, and nuclear medicine]. Productivity, total department workload, and unreported film rates were also assessed. Pre- and post-PACS findings were compared. Results: Between 2002-2006 the number of radiological patient episodes increased by 30% from 11,531/month to 15,057/month. This was accompanied by a smaller increase in WTE reporting radiologists, from 32 to 37 (15%). Mean reporting times have improved substantially post-PACS, plain radiograph reporting time decreased by 26% (from 6.8 to 5 days; p = 0.002) and specialty modalities by 24% (4.1 to 3.1 days; p < 0.001). Radiologist productivity has increased by 18% (337 films to 407 films/WTE radiologist/month). Unreported films have decreased from 5 to 4% for plain radiographs and are steady for specialty modalities (< 1%). In most areas improvements have been sustained over a 3-year period. Conclusion: Since the introduction of PACS, reporting times have decreased by 25% and the productivity improved by 18%. Sustained improvements are felt to reflect the efficiencies and cultural change that accompanied the introduction of PACS and digital dictation.

  3. Evaluation of Integrated Time-Temperature Effect in Pyrolysis Process of Historically Contaminated Soils with Cadmium (Cd and Lead (Pb

    Directory of Open Access Journals (Sweden)

    Bulmău C

    2013-04-01

    Full Text Available It is already known that heavy metals pollution causes important concern to human and ecosystem health. Heavy metals in soils at the European level represents 37.3% between main contaminates affecting soils (EEA, 2007. This paper illustrates results obtained in the framework of laboratory experiments concerning the evaluation of integrated time-temperature effect in pyrolysis process applied to contaminated soil by two different ways: it is about heavy metals historically contaminated soil from one of the most polluted areas within Romania, and artificially contaminated with PCB-containing transformer oil. In particular, the authors focused on a recent evaluation of pyrolysis efficiency on removing lead (Pb and cadmium (Cd from the contaminated soil. The experimental study evaluated two important parameters related to the studied remediation methodology: thermal process temperature and the retention time in reactor of the contaminated soils. The remediation treatments were performed in a rotary kiln reactor, taking into account three process temperatures (400°C, 600°C and 800°C and two retention times: 30 min. and 60 min. Completed analyses have focused on pyrolysis solids and gas products. Consequently, both ash and gas obtained after pyrolysis process were subjected to chemical analyses.

  4. Complexity Variability Assessment of Nonlinear Time-Varying Cardiovascular Control

    Science.gov (United States)

    Valenza, Gaetano; Citi, Luca; Garcia, Ronald G.; Taylor, Jessica Noggle; Toschi, Nicola; Barbieri, Riccardo

    2017-02-01

    The application of complex systems theory to physiology and medicine has provided meaningful information about the nonlinear aspects underlying the dynamics of a wide range of biological processes and their disease-related aberrations. However, no studies have investigated whether meaningful information can be extracted by quantifying second-order moments of time-varying cardiovascular complexity. To this extent, we introduce a novel mathematical framework termed complexity variability, in which the variance of instantaneous Lyapunov spectra estimated over time serves as a reference quantifier. We apply the proposed methodology to four exemplary studies involving disorders which stem from cardiology, neurology and psychiatry: Congestive Heart Failure (CHF), Major Depression Disorder (MDD), Parkinson’s Disease (PD), and Post-Traumatic Stress Disorder (PTSD) patients with insomnia under a yoga training regime. We show that complexity assessments derived from simple time-averaging are not able to discern pathology-related changes in autonomic control, and we demonstrate that between-group differences in measures of complexity variability are consistent across pathologies. Pathological states such as CHF, MDD, and PD are associated with an increased complexity variability when compared to healthy controls, whereas wellbeing derived from yoga in PTSD is associated with lower time-variance of complexity.

  5. Eclipse-Free-Time Assessment Tool for IRIS

    Science.gov (United States)

    Eagle, David

    2012-01-01

    IRIS_EFT is a scientific simulation that can be used to perform an Eclipse-Free- Time (EFT) assessment of IRIS (Infrared Imaging Surveyor) mission orbits. EFT is defined to be those time intervals longer than one day during which the IRIS spacecraft is not in the Earth s shadow. Program IRIS_EFT implements a special perturbation of orbital motion to numerically integrate Cowell's form of the system of differential equations. Shadow conditions are predicted by embedding this integrator within Brent s method for finding the root of a nonlinear equation. The IRIS_EFT software models the effects of the following types of orbit perturbations on the long-term evolution and shadow characteristics of IRIS mission orbits. (1) Non-spherical Earth gravity, (2) Atmospheric drag, (3) Point-mass gravity of the Sun, and (4) Point-mass gravity of the Moon. The objective of this effort was to create an in-house computer program that would perform eclipse-free-time analysis. of candidate IRIS spacecraft mission orbits in an accurate and timely fashion. The software is a suite of Fortran subroutines and data files organized as a "computational" engine that is used to accurately predict the long-term orbit evolution of IRIS mission orbits while searching for Earth shadow conditions.

  6. Screening and assessment of solidification/stabilization amendments suitable for soils of lead-acid battery contaminated site.

    Science.gov (United States)

    Zhang, Zhuo; Guo, Guanlin; Teng, Yanguo; Wang, Jinsheng; Rhee, Jae Seong; Wang, Sen; Li, Fasheng

    2015-05-15

    Lead exposure via ingestion of soil and dust generally occurs at lead-acid battery manufacturing and recycling sites. Screening solidification/stabilization (S/S) amendments suitable for lead contaminated soil in an abandoned lead-acid battery factory site was conducted based on its chemical forms and environmental risks. Twelve amendments were used to immobilize the Pb in soil and assess the solidification/stabilization efficiency by toxicity leaching tests. The results indicated that three amendments, KH₂PO₄ (KP), KH₂PO₄:oyster shell power=1:1 (by mass ratio; SPP), and KH₂PO₄:sintered magnesia=1:1 (by mass ratio; KPM) had higher remediation efficiencies that led to a 92% reduction in leachable Pb with the addition of 5% amendments, while the acid soluble fraction of Pb (AS-Pb) decreased by 41-46% and the residual fraction (RS-Pb) increased by 16-25%. The S/S costs of the three selected amendments KP, SPP, and KPM could be controlled to $22.3 per ton of soil when the Pb concentration in soil ranged from 2000 to 3000 mg/kg. The results of this study demonstrated that KP, SPP, and KPM can effectively decrease bioavailability of Pb. These findings could provide basis for decision-making of S/S remediation of lead-acid battery contaminated sites. Copyright © 2015 Elsevier B.V. All rights reserved.

  7. Role of sintering time, crystalline phases and symmetry in the piezoelectric properties of lead-free KNN-modified ceramics

    International Nuclear Information System (INIS)

    Rubio-Marcos, F.; Marchet, P.; Merle-Mejean, T.; Fernandez, J.F.

    2010-01-01

    Lead-free KNN-modified piezoceramics of the system (Li,Na,K)(Nb,Ta,Sb)O 3 were prepared by conventional solid-state sintering. The X-ray diffraction patterns revealed a perovskite phase, together with some minor secondary phase, which was assigned to K 3 LiNb 6 O 17 , tetragonal tungsten-bronze (TTB). A structural evolution toward a pure tetragonal structure with the increasing sintering time was observed, associated with the decrease of TTB phase. A correlation between higher tetragonality and higher piezoelectric response was clearly evidenced. Contrary to the case of the LiTaO 3 modified KNN, very large abnormal grains with TTB structure were not detected. As a consequence, the simultaneous modification by tantalum and antimony seems to induce during sintering a different behaviour from the one of LiTaO 3 modified KNN.

  8. Role of sintering time, crystalline phases and symmetry in the piezoelectric properties of lead-free KNN-modified ceramics

    Energy Technology Data Exchange (ETDEWEB)

    Rubio-Marcos, F., E-mail: frmarcos@icv.csic.es [Electroceramic Department, Instituto de Ceramica y Vidrio, CSIC, Kelsen 5, 28049 Madrid (Spain); Marchet, P.; Merle-Mejean, T. [SPCTS, UMR 6638 CNRS, Universite de Limoges, 123, Av. A. Thomas, 87060 Limoges (France); Fernandez, J.F. [Electroceramic Department, Instituto de Ceramica y Vidrio, CSIC, Kelsen 5, 28049 Madrid (Spain)

    2010-09-01

    Lead-free KNN-modified piezoceramics of the system (Li,Na,K)(Nb,Ta,Sb)O{sub 3} were prepared by conventional solid-state sintering. The X-ray diffraction patterns revealed a perovskite phase, together with some minor secondary phase, which was assigned to K{sub 3}LiNb{sub 6}O{sub 17}, tetragonal tungsten-bronze (TTB). A structural evolution toward a pure tetragonal structure with the increasing sintering time was observed, associated with the decrease of TTB phase. A correlation between higher tetragonality and higher piezoelectric response was clearly evidenced. Contrary to the case of the LiTaO{sub 3} modified KNN, very large abnormal grains with TTB structure were not detected. As a consequence, the simultaneous modification by tantalum and antimony seems to induce during sintering a different behaviour from the one of LiTaO{sub 3} modified KNN.

  9. An accuracy assessment of realtime GNSS time series toward semi- real time seafloor geodetic observation

    Science.gov (United States)

    Osada, Y.; Ohta, Y.; Demachi, T.; Kido, M.; Fujimoto, H.; Azuma, R.; Hino, R.

    2013-12-01

    Large interplate earthquake repeatedly occurred in Japan Trench. Recently, the detail crustal deformation revealed by the nation-wide inland GPS network called as GEONET by GSI. However, the maximum displacement region for interplate earthquake is mainly located offshore region. GPS/Acoustic seafloor geodetic observation (hereafter GPS/A) is quite important and useful for understanding of shallower part of the interplate coupling between subducting and overriding plates. We typically conduct GPS/A in specific ocean area based on repeated campaign style using research vessel or buoy. Therefore, we cannot monitor the temporal variation of seafloor crustal deformation in real time. The one of technical issue on real time observation is kinematic GPS analysis because kinematic GPS analysis based on reference and rover data. If the precise kinematic GPS analysis will be possible in the offshore region, it should be promising method for real time GPS/A with USV (Unmanned Surface Vehicle) and a moored buoy. We assessed stability, precision and accuracy of StarFireTM global satellites based augmentation system. We primarily tested for StarFire in the static condition. In order to assess coordinate precision and accuracy, we compared 1Hz StarFire time series and post-processed precise point positioning (PPP) 1Hz time series by GIPSY-OASIS II processing software Ver. 6.1.2 with three difference product types (ultra-rapid, rapid, and final orbits). We also used difference interval clock information (30 and 300 seconds) for the post-processed PPP processing. The standard deviation of real time StarFire time series is less than 30 mm (horizontal components) and 60 mm (vertical component) based on 1 month continuous processing. We also assessed noise spectrum of the estimated time series by StarFire and post-processed GIPSY PPP results. We found that the noise spectrum of StarFire time series is similar pattern with GIPSY-OASIS II processing result based on JPL rapid orbit

  10. Comparison of four bioindication methods for assessing the degree of environmental lead and cadmium pollution

    Energy Technology Data Exchange (ETDEWEB)

    Dmuchowski, Wojciech, E-mail: w.dmuchowski@obpan.pl [Botanical Garden-Center for Conservation of Biological Diversity, Polish Academy of Science, Prawdziwka 2, 02-973 Warsaw (Poland); Warsaw University of Life Sciences-SGGW, Faculty of Agriculture and Biology, 159 Nowoursynowska 159, 02-776 Warsaw (Poland); Gozdowski, Dariusz, E-mail: dariusz_gozdowski@sggw.pl [Warsaw University of Life Sciences-SGGW, Faculty of Agriculture and Biology, 159 Nowoursynowska 159, 02-776 Warsaw (Poland); Baczewska, Aneta Helena [Botanical Garden-Center for Conservation of Biological Diversity, Polish Academy of Science, Prawdziwka 2, 02-973 Warsaw (Poland)

    2011-12-15

    Highlights: Black-Right-Pointing-Pointer In this study we examined level of contamination in extremely heavy polluted area. Black-Right-Pointing-Pointer We examined four various bioindication methods. Black-Right-Pointing-Pointer Results were presented in pollution maps. Black-Right-Pointing-Pointer We evaluated relationships between examined bioindication methods. - Abstract: The purpose of this study was to assess the application of several bioindication methods for the monitoring of environmental pollution from Pb and Cd. The study area centered on the town of Olkusz, Poland, which is one of the oldest centers for the metallurgical industry in Europe. The assessment of environmental pollution due to metals was performed using four frequently used bioindication methods: moss-bag (Sphagnum fallax), determination of metal accumulation in Pleurozium schreberi, silver birch foliage, and Scots pine needles. The region of Olkusz, and especially the area surrounding the mining and metallurgical Boleslaw complex, was extremely contaminated with Pb and Cd. The results of the investigations are presented as contamination deposition maps. Despite the application of various methods and the resulting diversity of the specific exposure periods for different biomonitors, the spatial distribution of contamination shown on the maps was similar, as confirmed by the statistical analysis of the results.

  11. Comparison of four bioindication methods for assessing the degree of environmental lead and cadmium pollution

    International Nuclear Information System (INIS)

    Dmuchowski, Wojciech; Gozdowski, Dariusz; Baczewska, Aneta Helena

    2011-01-01

    Highlights: ► In this study we examined level of contamination in extremely heavy polluted area. ► We examined four various bioindication methods. ► Results were presented in pollution maps. ► We evaluated relationships between examined bioindication methods. - Abstract: The purpose of this study was to assess the application of several bioindication methods for the monitoring of environmental pollution from Pb and Cd. The study area centered on the town of Olkusz, Poland, which is one of the oldest centers for the metallurgical industry in Europe. The assessment of environmental pollution due to metals was performed using four frequently used bioindication methods: moss-bag (Sphagnum fallax), determination of metal accumulation in Pleurozium schreberi, silver birch foliage, and Scots pine needles. The region of Olkusz, and especially the area surrounding the mining and metallurgical Bolesław complex, was extremely contaminated with Pb and Cd. The results of the investigations are presented as contamination deposition maps. Despite the application of various methods and the resulting diversity of the specific exposure periods for different biomonitors, the spatial distribution of contamination shown on the maps was similar, as confirmed by the statistical analysis of the results.

  12. Comparison of four bioindication methods for assessing the degree of environmental lead and cadmium pollution.

    Science.gov (United States)

    Dmuchowski, Wojciech; Gozdowski, Dariusz; Baczewska, Aneta Helena

    2011-12-15

    The purpose of this study was to assess the application of several bioindication methods for the monitoring of environmental pollution from Pb and Cd. The study area centered on the town of Olkusz, Poland, which is one of the oldest centers for the metallurgical industry in Europe. The assessment of environmental pollution due to metals was performed using four frequently used bioindication methods: moss-bag (Sphagnum fallax), determination of metal accumulation in Pleurozium schreberi, silver birch foliage, and Scots pine needles. The region of Olkusz, and especially the area surrounding the mining and metallurgical Bolesław complex, was extremely contaminated with Pb and Cd. The results of the investigations are presented as contamination deposition maps. Despite the application of various methods and the resulting diversity of the specific exposure periods for different biomonitors, the spatial distribution of contamination shown on the maps was similar, as confirmed by the statistical analysis of the results. Copyright © 2011 Elsevier B.V. All rights reserved.

  13. Global assessment of oceanic lead pollution using sperm whales (Physeter macrocephalus) as an indicator species.

    Science.gov (United States)

    Savery, Laura C; Wise, Sandra S; Falank, Carolyne; Wise, James; Gianios, Christy; Douglas Thompson, W; Perkins, Christopher; Zheng, Tongzhang; Zhu, Cairong; Wise, John Pierce

    2014-02-15

    Lead (Pb) is an oceanic pollutant of global concern. Anthropogenic activities are increasing oceanic levels, but to an unknown extent. The sperm whale (Physeter macrocephalus) has a global distribution and high trophic level. The aim of this study was to establish a global baseline of oceanic Pb concentrations using free-ranging sperm whales as an indicator species. Skin biopsies (n=337) were collected during the voyage of the Odyssey (2000-2005) from 17 regions considering gender and age. Pb was detectable in 315 samples with a global mean of 1.6 ug/gww ranging from 0.1 to 129.6 ug/gww. Papua New Guinea, Bahamas and Australia had the highest regional mean with 6.1, 3.4, and 3.1 ug/gww, respectively. Pb concentrations were not significantly different between sex and age in males. This is the first global toxicological dataset for Pb in a marine mammal and confirms Pb is widely distributed with hotspots in some regions. Copyright © 2014. Published by Elsevier Ltd.

  14. Assessment of lead in blood samples of children residing in the vicinity of industries

    International Nuclear Information System (INIS)

    Shah, F.; Kazi, T.G.; Afridi, H.I.; Brahaman, K.D.; Arain, S.S.; Panhwar, A.H.

    2013-01-01

    The aim of present study was to determine the lead (Pb) distributions in blood and prevalence of elevated Pb exposure among children, age ranged (5-10 years), residing near industrialized region of Hyderabad city, Pakistan. For comparison, biological samples of children of same age group from non-industrial area were also analyzed. The Pb concentration in blood samples was determined by electrothermal atomic absorption spectrometry, prior to microwave assisted acid digestion. The results showed that significantly higher proportion of children living in the vicinity of industrial area, had blood Pb levels (BLL) in the range of 15.4-35.6 micro g/dL, and 8.51-16.7 micro g/dL for those of non-industrial area. The blood Pb level was higher in boys of both groups as compared to girls of same age group, but the difference was not significant (p=0.178). Negative correlation was observed between BLL and hemoglobin levels (p<0.001), while positive correlation was observed between BLL and age. (author)

  15. Assessment of Hair Aluminum, Lead, and Mercury in a Sample of Autistic Egyptian Children: Environmental Risk Factors of Heavy Metals in Autism.

    Science.gov (United States)

    Mohamed, Farida El Baz; Zaky, Eman Ahmed; El-Sayed, Adel Bassuoni; Elhossieny, Reham Mohammed; Zahra, Sally Soliman; Salah Eldin, Waleed; Youssef, Walaa Yousef; Khaled, Rania Abdelmgeed; Youssef, Azza Mohamed

    2015-01-01

    The etiological factors involved in the etiology of autism remain elusive and controversial, but both genetic and environmental factors have been implicated. The aim of this study was to assess the levels and possible environmental risk factors and sources of exposure to mercury, lead, and aluminum in children with autism spectrum disorder (ASD) as compared to their matched controls. One hundred ASD children were studied in comparison to 100 controls. All participants were subjected to clinical evaluation and measurement of mercury, lead, and aluminum through hair analysis which reflects past exposure. The mean Levels of mercury, lead, and aluminum in hair of the autistic patients were significantly higher than controls. Mercury, lead, and aluminum levels were positively correlated with maternal fish consumptions, living nearby gasoline stations, and the usage of aluminum pans, respectively. Levels of mercury, lead, and aluminum in the hair of autistic children are higher than controls. Environmental exposure to these toxic heavy metals, at key times in development, may play a causal role in autism.

  16. Assessment of colonic transit time using MRI: a feasibility study

    Energy Technology Data Exchange (ETDEWEB)

    Buhmann, Sonja; Reiser, Maximilian F.; Lienemann, Andreas [Ludwig-Maximilians-University, Department of Clinical Radiology, Campus Grosshadern, Munich (Germany); Kirchhoff, Chlodwig; Ladurner, Roland; Mussack, Thomas [Ludwig-Maximilians-University, Department of Surgery and Traumatology, Campus Innenstadt, Munich (Germany)

    2007-03-15

    The aim of this pilot study was to evaluate a new, non-invasive examination method using MRI for the quantification of the colonic transit time after oral administration of gadolinium-saline solution filled capsules. Healthy volunteers without previous or acute symptoms of gastrointestinal disorders were enrolled. After a 3-day diet for the standardization of gastrocolonic content the volunteers swallowed five Gd-DTPA/saline 0.9%-filledcapsules. Seven different concentrations of Gd-DTPA/saline 0.9% solution between 1:0 and 0:1 were tested in a dilution series. Following ingestion of capsules, coronal Flash T1 and True Fisp sequences using a 1.5 Tesla system were obtained at 0 h, 3 h, 6 h, 12 h, 24 h, 36 h and 60 h. Sequences were analyzed by two independent experts for locating the capsules. Overall colonic transit time was separately analyzed for both genders. Fifteen healthy volunteers (7 females, 8 males; mean age 34{+-}13 years) were enrolled. The phantom study provided the best contrast in both the T1-and T2-weighted sequences defining a ratio of 1:10 for Gd-DTPA/saline 0.9% solution. The mean transit time accounted for 41{+-}9 h in women and for 31{+-}10 h in men. MRI is an adequate method for the assessment of colonic transit time offering the advantages of no exposure to radiation, short examination time, possible dynamic evaluation of the transit and the practicability in terms of a future adoption to clinical routine. (orig.)

  17. Assessment of colonic transit time using MRI: a feasibility study

    International Nuclear Information System (INIS)

    Buhmann, Sonja; Reiser, Maximilian F.; Lienemann, Andreas; Kirchhoff, Chlodwig; Ladurner, Roland; Mussack, Thomas

    2007-01-01

    The aim of this pilot study was to evaluate a new, non-invasive examination method using MRI for the quantification of the colonic transit time after oral administration of gadolinium-saline solution filled capsules. Healthy volunteers without previous or acute symptoms of gastrointestinal disorders were enrolled. After a 3-day diet for the standardization of gastrocolonic content the volunteers swallowed five Gd-DTPA/saline 0.9%-filledcapsules. Seven different concentrations of Gd-DTPA/saline 0.9% solution between 1:0 and 0:1 were tested in a dilution series. Following ingestion of capsules, coronal Flash T1 and True Fisp sequences using a 1.5 Tesla system were obtained at 0 h, 3 h, 6 h, 12 h, 24 h, 36 h and 60 h. Sequences were analyzed by two independent experts for locating the capsules. Overall colonic transit time was separately analyzed for both genders. Fifteen healthy volunteers (7 females, 8 males; mean age 34±13 years) were enrolled. The phantom study provided the best contrast in both the T1-and T2-weighted sequences defining a ratio of 1:10 for Gd-DTPA/saline 0.9% solution. The mean transit time accounted for 41±9 h in women and for 31±10 h in men. MRI is an adequate method for the assessment of colonic transit time offering the advantages of no exposure to radiation, short examination time, possible dynamic evaluation of the transit and the practicability in terms of a future adoption to clinical routine. (orig.)

  18. Geostatistical approach for assessing soil volumes requiring remediation: validation using lead-polluted soils underlying a former smelting works.

    Science.gov (United States)

    Demougeot-Renard, Helene; De Fouquet, Chantal

    2004-10-01

    Assessing the volume of soil requiring remediation and the accuracy of this assessment constitutes an essential step in polluted site management. If this remediation volume is not properly assessed, misclassification may lead both to environmental risks (polluted soils may not be remediated) and financial risks (unexpected discovery of polluted soils may generate additional remediation costs). To minimize such risks, this paper proposes a geostatistical methodology based on stochastic simulations that allows the remediation volume and the uncertainty to be assessed using investigation data. The methodology thoroughly reproduces the conditions in which the soils are classified and extracted at the remediation stage. The validity of the approach is tested by applying it on the data collected during the investigation phase of a former lead smelting works and by comparing the results with the volume that has actually been remediated. This real remediated volume was composed of all the remediation units that were classified as polluted after systematic sampling and analysis during clean-up stage. The volume estimated from the 75 samples collected during site investigation slightly overestimates (5.3% relative error) the remediated volume deduced from 212 remediation units. Furthermore, the real volume falls within the range of uncertainty predicted using the proposed methodology.

  19. Exposure assessment in Beijing, China: biological agents, ultrafine particles, and lead.

    Science.gov (United States)

    Dong, Shuofei; Yao, Maosheng

    2010-11-01

    In this study, air samples were taken using a BioSampler and gelatin filters from six sites in Beijing: office, hospital, student dormitory, train station, subway, and a commercial street. Dust samples were also collected using a surface sampler from the same environments. Limulus amoebocyte lysate (LAL) and Glucatell assays were used to quantify sample endotoxin and (1,3)-β-d-glucan concentration levels, respectively. Enzyme-linked immunosorbent assay (ELISA) was used to measure the dust mite allergens (Der p 1 and Der f 1). Ultrafine particle and lead concentrations in these sampling sites were also measured using P-Trak and atomic absorption spectrometer, respectively. Analysis of variance (ANOVA) and linear regression analysis were used to analyze the concentration data. Higher culturable bacteria (12,639 CFU/m3) and fungi (1,806 CFU/m3) concentrations were observed for the train station and the subway system, respectively. For the rest of sampling sites, their concentrations were comparable to those found in western countries, ranging from 990 to 2,276 CFU/m3 for bacteria, and from 119 to 269 CFU/m3 for fungi. ANOVA analysis indicated that there were statistically significant differences between the culturable bacterial and fungal concentration levels obtained for different sites (p value=0.0001 and 0.0047). As for dust allergens, endotoxin, and (1,3)-β-D-glucan, their concentrations also seemed to be comparable to those found in the developed countries. Airborne allergen concentrations ranged from 16 to 68 ng/m3. The dust-borne allergen concentration was observed to range from 0.063 to 0.327 ng/mg. As for endotoxin, the highest airborne concentration of 25.24 ng/m3 was observed for the commercial street, and others ranged from 0.0427 to 0.1259 ng/m3. And dust-borne endotoxin concentration ranged from 58.83 to 6,427.4 ng/mg. For (1,3)-β-D-glucan, the airborne concentration ranged from 0.02 to 1.2 ng/m3. Linear regression analyses showed that there existed

  20. Assessment of Environmental Distribution of Lead in Some Municipalities of South-Eastern Nigeria

    Directory of Open Access Journals (Sweden)

    John Kanayochukwu Nduka

    2010-06-01

    Full Text Available Lead (Pb levels were measured in roadside surface soils, dust particles and rain water samples from the urban cities of Enugu, Awka, Onitsha, Nnewi, Aba, Port Harcourt and Warri in Southern Nigeria in 2007 and 2008. Samples were collected during the dry season, while rain water samples were collected during the early rain (April–June, mid rain (July–August and late rain seasons (September–October for the two years. Soil samples were collected from traffic congested roads, dust was collected by tying a plastic basin on a pole 1.5 m above ground level and leaving it for 45 days. Rain samples were collected from three equidistant points. Samples were analyzed by AAS. The highest soil Pb of 120.00 ± 0.00 and 80.36 ± 0.00 mg/kg were reported in Onitsha for 2007 and 2008, respectively. Nnewi showed 33.40 ± 0.01 and 4,238.29 ± 0.00 mg/kg for 2007 and 2008. Aba had 22.56 ± 0.01 and 21.28 ± 0.00 mg/kg for 2007 and 2008. Higher concentrations were recorded for Nnewi and Port Harcourt in 2008 than in 2007. Enugu had more in 2007 while Awka had more in 2008. Dust Pb ranged from 0.13–0.49 mg/kg and 0.15–0.47 mg/kg for 2007 and 2008, respectively. Rain samples had the least Pb concentration, ranging from 0.103 ± 0.000 to 0.163 ± 0.046 mg/L. We may conclude that Nigerians are exposed to environmental Pb.

  1. Assessment of variations in control of asthma over time.

    Science.gov (United States)

    Combescure, C; Chanez, P; Saint-Pierre, P; Daurès, J P; Proudhon, H; Godard, P

    2003-08-01

    Control and severity of asthma are two different but complementary concepts. The severity of asthma could influence the control over time. The aim of this study was to demonstrate this relationship. A total 365 patients with persistent asthma (severity) were enrolled and followed-up prospectively. Data were analysed using a continuous time homogeneous Markov model of the natural history of asthma. Control of asthma was defined according to three health states which were qualified: optimal, suboptimal and unacceptable control (states 1, 2 and 3). Transition forces (denoted lambda(ij) from state i to state j) and transition probabilities between control states were assessed and the results stratified by asthma severity were compared. Models were validated by comparing expected and observed numbers of patients in the different states. Transition probabilities stabilised between 100-250 days and more rapidly in patients with mild-to-moderate asthma. Patients with mild-to-moderate asthma in suboptimal or unacceptable control had a high probability of transition directly to optimal control. Patients with severe asthma had a tendency to remain in unacceptable control. A Markov model is a useful tool to model the control of asthma over time. Severity modified clearly the health states. It could be used to compare the performance of different approaches to asthma management.

  2. Therapeutic Assessment of Complex Trauma: A Single-Case Time-Series Study.

    Science.gov (United States)

    Tarocchi, Anna; Aschieri, Filippo; Fantini, Francesca; Smith, Justin D

    2013-06-01

    The cumulative effect of repeated traumatic experiences in early childhood incrementally increases the risk of adjustment problems later in life. Surviving traumatic environments can lead to the development of an interrelated constellation of emotional and interpersonal symptoms termed complex posttraumatic stress disorder (CPTSD). Effective treatment of trauma begins with a multimethod psychological assessment and requires the use of several evidence-based therapeutic processes, including establishing a safe therapeutic environment, reprocessing the trauma, constructing a new narrative, and managing emotional dysregulation. Therapeutic Assessment (TA) is a semistructured, brief intervention that uses psychological testing to promote positive change. The case study of Kelly, a middle-aged woman with a history of repeated interpersonal trauma, illustrates delivery of the TA model for CPTSD. Results of this single-case time-series experiment indicate statistically significant symptom improvement as a result of participating in TA. We discuss the implications of these findings for assessing and treating trauma-related concerns, such as CPTSD.

  3. The Impact of Weather Forecasts of Various Lead Times on Snowmaking Decisions Made for the 2010 Vancouver Olympic Winter Games

    Science.gov (United States)

    Doyle, Chris

    2014-01-01

    The Vancouver 2010 Winter Olympics were held from 12 to 28 February 2010, and the Paralympic events followed 2 weeks later. During the Games, the weather posed a grave threat to the viability of one venue and created significant complications for the event schedule at others. Forecasts of weather with lead times ranging from minutes to days helped organizers minimize disruptions to sporting events and helped ensure all medal events were successfully completed. Of comparable importance, however, were the scenarios and forecasts of probable weather for the winter in advance of the Games. Forecasts of mild conditions at the time of the Games helped the Games' organizers mitigate what would have been very serious potential consequences for at least one venue. Snowmaking was one strategy employed well in advance of the Games to prepare for the expected conditions. This short study will focus on how operational decisions were made by the Games' organizers on the basis of both climatological and snowmaking forecasts during the pre-Games winter. An attempt will be made to quantify, economically, the value of some of the snowmaking forecasts made for the Games' operators. The results obtained indicate that although the economic value of the snowmaking forecast was difficult to determine, the Games' organizers valued the forecast information greatly. This suggests that further development of probabilistic forecasts for applications like pre-Games snowmaking would be worthwhile.

  4. Pulse of inflammatory proteins in the pregnant uterus of European polecats (Mustela putorius) leading to the time of implantation.

    Science.gov (United States)

    Lindeberg, Heli; Burchmore, Richard J S; Kennedy, Malcolm W

    2017-03-01

    Uterine secretory proteins protect the uterus and conceptuses against infection, facilitate implantation, control cellular damage resulting from implantation, and supply pre-implantation embryos with nutrients. Unlike in humans, the early conceptus of the European polecat ( Mustela putorius ; ferret) grows and develops free in the uterus until implanting at about 12 days after mating. We found that the proteins appearing in polecat uteri changed dramatically with time leading to implantation. Several of these proteins have also been found in pregnant uteri of other eutherian mammals. However, we found a combination of two increasingly abundant proteins that have not been recorded before in pre-placentation uteri. First, the broad-spectrum proteinase inhibitor α 2 -macroglobulin rose to dominate the protein profile by the time of implantation. Its functions may be to limit damage caused by the release of proteinases during implantation or infection, and to control other processes around sites of implantation. Second, lipocalin-1 (also known as tear lipocalin) also increased substantially in concentration. This protein has not previously been recorded as a uterine secretion in pregnancy in any species. If polecat lipocalin-1 has similar biological properties to that of humans, then it may have a combined function in antimicrobial protection and transporting or scavenging lipids. The changes in the uterine secretory protein repertoire of European polecats is therefore unusual, and may be representative of pre-placentation supportive uterine secretions in mustelids (otters, weasels, badgers, mink, wolverines) in general.

  5. Model Penjadwalan Pengiriman Pasokan pada Strategi Multi-Supplier dengan Variasi Harga dan Lead Time untuk Permintaan Stokastik

    Directory of Open Access Journals (Sweden)

    Nur Aini Masruroh

    2015-06-01

    Full Text Available Multi-supplier is one of the strategies to minimize holding cost and average stock-out cost as long as to stabilize the supply of raw materials. The common problems that the firms may face when applying the multi-supplier strategy are determining the right schedule and quantity ordered for each supplier. Complexity of the problem increases with the facts that each supplier may have different parameters, demand is uncertain, and the firms’ constraints. Thus, this research is done to answer two main objectives: (1 to determine the optimum safety time (minimum raw material inventory to prevent the stockout due to the demand uncertainty and (2 to determine the right schedule and quantity ordered for each supplier considering the different suppliers parameters: price, lead time, and supply capacity. The problem is modeled in Mixed Integer Linear Programming with total minimum inventory cost as the objective. With the aim of testing the model, a case of multinational company that apply the multi-supplier strategy is used.

  6. Diagnostic value of ST-segment deviations during cardiac exercise stress testing: Systematic comparison of different ECG leads and time-points.

    Science.gov (United States)

    Puelacher, Christian; Wagener, Max; Abächerli, Roger; Honegger, Ursina; Lhasam, Nundsin; Schaerli, Nicolas; Prêtre, Gil; Strebel, Ivo; Twerenbold, Raphael; Boeddinghaus, Jasper; Nestelberger, Thomas; Rubini Giménez, Maria; Hillinger, Petra; Wildi, Karin; Sabti, Zaid; Badertscher, Patrick; Cupa, Janosch; Kozhuharov, Nikola; du Fay de Lavallaz, Jeanne; Freese, Michael; Roux, Isabelle; Lohrmann, Jens; Leber, Remo; Osswald, Stefan; Wild, Damian; Zellweger, Michael J; Mueller, Christian; Reichlin, Tobias

    2017-07-01

    Exercise ECG stress testing is the most widely available method for evaluation of patients with suspected myocardial ischemia. Its major limitation is the relatively poor accuracy of ST-segment changes regarding ischemia detection. Little is known about the optimal method to assess ST-deviations. A total of 1558 consecutive patients undergoing bicycle exercise stress myocardial perfusion imaging (MPI) were enrolled. Presence of inducible myocardial ischemia was adjudicated using MPI results. The diagnostic value of ST-deviations for detection of exercise-induced myocardial ischemia was systematically analyzed 1) for each individual lead, 2) at three different intervals after the J-point (J+40ms, J+60ms, J+80ms), and 3) at different time points during the test (baseline, maximal workload, 2min into recovery). Exercise-induced ischemia was detected in 481 (31%) patients. The diagnostic accuracy of ST-deviations was highest at +80ms after the J-point, and at 2min into recovery. At this point, ST-amplitude showed an AUC of 0.63 (95% CI 0.59-0.66) for the best-performing lead I. The combination of ST-amplitude and ST-slope in lead I did not increase the AUC. Lead I reached a sensitivity of 37% and a specificity of 83%, with similar sensitivity to manual ECG analysis (34%, p=0.31) but lower specificity (90%, pST-deviations is highest when evaluated at +80ms after the J-point, and at 2min into recovery. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. Determination of toxic elements (mercury, cadmium, lead, tin and arsenic) in fish and shellfish samples. Risk assessment for the consumers.

    Science.gov (United States)

    Olmedo, P; Pla, A; Hernández, A F; Barbier, F; Ayouni, L; Gil, F

    2013-09-01

    Although fish intake has potential health benefits, the presence of metal contamination in seafood has raised public health concerns. In this study, levels of mercury, cadmium, lead, tin and arsenic have been determined in fresh, canned and frozen fish and shellfish products and compared with the maximum levels currently in force. In a further step, potential human health risks for the consumers were assessed. A total of 485 samples of the 43 most frequently consumed fish and shellfish species in Andalusia (Southern Spain) were analyzed for their toxic elements content. High mercury concentrations were found in some predatory species (blue shark, cat shark, swordfish and tuna), although they were below the regulatory maximum levels. In the case of cadmium, bivalve mollusks such as canned clams and mussels presented higher concentrations than fish, but almost none of the samples analyzed exceeded the maximum levels. Lead concentrations were almost negligible with the exception of frozen common sole, which showed median levels above the legal limit. Tin levels in canned products were far below the maximum regulatory limit, indicating that no significant tin was transferred from the can. Arsenic concentrations were higher in crustaceans such as fresh and frozen shrimps. The risk assessment performed indicated that fish and shellfish products were safe for the average consumer, although a potential risk cannot be dismissed for regular or excessive consumers of particular fish species, such as tuna, swordfish, blue shark and cat shark (for mercury) and common sole (for lead). Copyright © 2013 Elsevier Ltd. All rights reserved.

  8. Thermodynamic assessment of the Sn-Co lead-free solder system

    Science.gov (United States)

    Liu, Libin; Andersson, Cristina; Liu, Johan

    2004-09-01

    The Sn-Co-Cu eutectic alloy can be a less expensive alternative for the Sn-Ag-Cu alloy. In order to find the eutectic solder composition of the Sn-Co-Cu system, the Sn-Co binary system has been thoroughly assessed with the calculation of phase diagram (CALPHAD) method. The liquid phase, the FCC and HCP Co-rich solid solution, and the BCT Sn-rich solid solution have been described by the Redlich-Kister model. The Hillert-Jarl-Inden model has been used to describe the magnetic contributions to Gibbs energy in FCC and HCP. The CoSn2, CoSn, Co3Sn2_β, and Co3Sn2_α phases have been treated as stoichiometric phases. A series of thermodynamic parameters have been obtained. The calculated phase diagram and thermodynamic properties are in good agreement with the experimental data. The obtained thermodynamic data was used to extrapolate the ternary Sn-Co-Cu phase diagram. The composition of the Sn-rich eutectic point of the Sn-Co-Cu system was found to be 224°C, 0.4% Co, and 0.7% Cu.

  9. Time-dependent reliability analysis and condition assessment of structures

    International Nuclear Information System (INIS)

    Ellingwood, B.R.

    1997-01-01

    Structures generally play a passive role in assurance of safety in nuclear plant operation, but are important if the plant is to withstand the effect of extreme environmental or abnormal events. Relative to mechanical and electrical components, structural systems and components would be difficult and costly to replace. While the performance of steel or reinforced concrete structures in service generally has been very good, their strengths may deteriorate during an extended service life as a result of changes brought on by an aggressive environment, excessive loading, or accidental loading. Quantitative tools for condition assessment of aging structures can be developed using time-dependent structural reliability analysis methods. Such methods provide a framework for addressing the uncertainties attendant to aging in the decision process

  10. In vivo measurements of lead-210 for assessing cumulative radon exposure in uranium miners

    Energy Technology Data Exchange (ETDEWEB)

    Guilmette, R.A.; Laurer, G.R. [New York Univ. Inst. of Environmental Medicine, Tuxedo, NY (United States); Lambert, W.E.; Gilliland, F.D. [Univ. of New Mexico, Albuquerque, NM (United States)] [and others

    1995-12-01

    It has long been recognized that a major contributor to the uncertainty in risk analysis of lung cancer in uranium and other hard rock miners is the estimation of total radon progeny exposure of individual miners under study. These uncertainties arise from the fact that only a limited number of measurements of airborne {sup 222}Rn progeny concentrations were made in the mines during the times that the miners were being exposed, and that dosimeters capable of integrating the Rn progeny exposures of the miners did not exist. Historically, the cumulative exposures for individual uranium and other hard rock miners have been calculated by combining the employee`s work history, which may or may not have included time spent at different jobs within the mines and at different locations within the mines, with whatever periodic measurements of Rn and Rn progeny were available. The amount and quality of the measurement data varied enormously from mine to mine and from population to population. Because the quality of the exposure data collected during the period of active mining in the United STates cannot now be altered substantially, significant improvement in individual miner exposure estimates is only likely to be achieved if a new cumulative exposure metric is developed and implemented. The decay chain of Rn includes the production of {sup 210}Pb, which can accumulate in the skeleton in amounts proportional to the intake of Rn progeny. We hypothesize that the in vivo measurement of {sup 210}Pb in the skulls of miners will provide such a metric. In summary, the primary purpose of this pilot study to demonstrate the feasibility of measuring {sup 210}Pb in the heads of former uranium miners has been accomplished.

  11. In vivo measurements of lead-210 for assessing cumulative radon exposure in uranium miners

    International Nuclear Information System (INIS)

    Guilmette, R.A.; Laurer, G.R.; Lambert, W.E.; Gilliland, F.D.

    1995-01-01

    It has long been recognized that a major contributor to the uncertainty in risk analysis of lung cancer in uranium and other hard rock miners is the estimation of total radon progeny exposure of individual miners under study. These uncertainties arise from the fact that only a limited number of measurements of airborne 222 Rn progeny concentrations were made in the mines during the times that the miners were being exposed, and that dosimeters capable of integrating the Rn progeny exposures of the miners did not exist. Historically, the cumulative exposures for individual uranium and other hard rock miners have been calculated by combining the employee's work history, which may or may not have included time spent at different jobs within the mines and at different locations within the mines, with whatever periodic measurements of Rn and Rn progeny were available. The amount and quality of the measurement data varied enormously from mine to mine and from population to population. Because the quality of the exposure data collected during the period of active mining in the United STates cannot now be altered substantially, significant improvement in individual miner exposure estimates is only likely to be achieved if a new cumulative exposure metric is developed and implemented. The decay chain of Rn includes the production of 210 Pb, which can accumulate in the skeleton in amounts proportional to the intake of Rn progeny. We hypothesize that the in vivo measurement of 210 Pb in the skulls of miners will provide such a metric. In summary, the primary purpose of this pilot study to demonstrate the feasibility of measuring 210 Pb in the heads of former uranium miners has been accomplished

  12. Real-Time Assessment and Diagnosis of Process Operating Performance

    Directory of Open Access Journals (Sweden)

    Shabnam Sedghi

    2017-04-01

    Full Text Available Over time, the performance of processes may deviate from the initial design due to process variations and uncertainties, making it necessary to develop systematic methods for online optimality assessment based on routine operating process data. Some processes have multiple operating modes caused by the set point change of the critical process variables to achieve different product specifications. On the other hand, the operating region in each operating mode can alter, due to uncertainties. In this paper, we will establish an optimality assessment framework for processes that typically have multi-mode, multi-region operations, as well as transitions between different modes. The kernel density approach for mode detection is adopted and improved for operating mode detection. For online mode detection, the model-based clustering discriminant analysis (MclustDA approach is incorporated with some a priori knowledge of the system. In addition, multi-modal behavior of steady-state modes is tackled utilizing the mixture probabilistic principal component regression (MPPCR method, and dynamic principal component regression (DPCR is used to investigate transitions between different modes. Moreover, a probabilistic causality detection method based on the sequential forward floating search (SFFS method is introduced for diagnosing poor or non-optimum behavior. Finally, the proposed method is tested on the Tennessee Eastman (TE benchmark simulation process in order to evaluate its performance.

  13. Assessment of the transmutation capability an accelerator driven system cooled by lead bismuth eutectic alloy

    International Nuclear Information System (INIS)

    Bianchi, F.; Peluso, V.; Calabrese; Chen, X.; Maschek, W.

    2007-01-01

    1. PURPOSE The reduction of long-lived fission products (LLFP) and minor actinides (MA) is a key point for the public acceptability and economy of nuclear energy. In principle, any nuclear fast reactor is able to burn and transmute MA, but the amount of MA content has to be limited a few percent, having unfavourable consequences on the coolant void reactivity, Doppler effect, and delayed neutron fraction, and therefore on the dynamic behaviour and control. Accelerator Driven Systems (ADS) are instead able to safely burn and/or transmute a large quantity of actinides and LLFP, as they do not rely on delayed neutrons for control or power change and the reactivity feedbacks have very little importance during accidents. Such systems are very innovative being based on the coupling of an accelerator with a subcritical system by means of a target system, where the neutronic source needed to maintain the neutron reaction chain is produced by spallation reactions. To this end the PDS-XADS (Preliminary Design Studies on an experimental Accelerator Driven System) project was funded by the European Community in the 5th Framework Program in order both to demonstrate the feasibility of the coupling between an accelerator and a sub-critical core loaded with standard MOX fuel and to investigate the transmutation capability in order to achieve values suitable for an Industrial Scale Transmuter. This paper summarizes and compares the results of neutronic calculations aimed at evaluating the transmutation capability of cores cooled by Lead-Bismuth Eutectic alloy and loaded with assemblies based on (Pu, Am, Cm) oxide dispersed in a molybdenum metal (CERMET) or magnesia (CERCER) matrices. It also describes the constraints considered in the design of such cores and describes the thermo-mechanical behaviour of these innovative fuels along the cycle. 2. DESCRIPTION OF THE WORK: The U-free composite fuels (CERMET and CERCER) were selected for this study, being considered at European level

  14. Real Time Assessment of Young Adults' Attitudes toward Tobacco Messages.

    Science.gov (United States)

    Hébert, Emily T; Vandewater, Elizabeth A; Businelle, Michael S; Harrell, Melissa B; Kelder, Steven H; Perry, Cheryl L

    2018-01-01

    We used ecological momentary assessment (EMA) to examine young adults' attitudes towards pro-tobacco messages encountered in real time and their association with intentions to use tobacco. Young adults (N = 92, ages 18-29) recorded sightings of marketing or social media related to tobacco in real time via mobile app for 28 days. Participants reported message characteristics, their attitudes towards the message, and intentions to use the depicted product for each submission. We used generalized linear mixed models to examine factors related to attitude towards message and intentions to use tobacco. Messages depicting e-cigarettes (p < .001) or hookah (p < .05) were associated with significantly more favorable attitudes compared with traditional cigarettes. Positive attitude towards the message was significantly associated with intention to use the depicted product (p < .001). Messages depicting e-cigarettes and hookah were significantly associated with higher intention to use. Message source was not significantly related to attitudes towards the message or product use intentions. Marketing featuring e-cigarettes and hookah is an important target for future regulation. Given that pro-tobacco and e-cigarette messages are prevalent online, future research should consider the Internet and social media as important venues for counter-marketing and intervention efforts.

  15. Beginning science teachers' performances: Assessment in times of reform

    Science.gov (United States)

    Budzinsky, Fie K.

    2000-10-01

    The current reform in science education and the research on effective teaching and student learning have reinforced the importance of teacher competency. To better measure performances in the teaching of science, performance assessment has been added to Connecticut's licensure process for beginning science teachers. Teaching portfolios are used to document teaching and learning over time. Portfolios, however, are not without problems. One of the major concerns with the portfolio assessment process is its subjectivity. Assessors may not have opportunities to ask clarifying or follow-up questions to enhance the interpretation of a teacher's performance. In addition, portfolios often contain components based on self-documentation, which are subjective. Furthermore, the use of portfolios raises test equity issues. These concerns present challenges for persons in charge of establishing the validity of a portfolio-based licensure process. In high-stakes decision processes, such as teaching licensure, the validity of the assessment instruments must be studied. The primary purpose of this study was to explore the criterion-related validity of the Connecticut State Department of Education's Beginning Science Teaching Portfolio by comparing the interpretations of performances from science teaching portfolios to those derived from another assessment method, the Expert Science Teaching Educational and Evaluation Model, (ESTEEM). The analysis of correlations between the Beginning Science Teaching Portfolio and ESTEEM instrument scores was the primary method for establishing support for validity. The results indicated moderate correlations between all Beginning Science Teaching Portfolio and ESTEEM category and total variables. Multiple regression was used to examine whether differences existed in beginning science teachers' performances based on gender, poverty group, school level, and science discipline taught. None of these variables significantly contributed to the

  16. Assessment of the effectiveness of attenuation of leaded aprons through TLD dosimetry and Monte Carlo simulation method

    Energy Technology Data Exchange (ETDEWEB)

    Olaya D, H.; Diaz M, J. A.; Martinez O, S. A. [Universidad Pedagogica y Tecnologica de Colombia, Grupo de Fisica Nuclear Aplicada y Simulacion, 150003 Tunja, Boyaca (Colombia); Vega C, H. R. [Universidad Autonoma de Zacatecas, Unidad Academica de Estudios Nucleares, Cipres No. 10, Fracc. La Penuela, 98068 Zacatecas, Zac. (Mexico)

    2016-10-15

    Were performed experimental setups using an X-ray equipment continuous emission Pantak DXT-3000 and three types of leaded aprons with thickness of 0.25, 0.5 and 0.75 mm coated with Mylar Fiber coated Mylar on its surface. Apron was located at a distance of 2.5 m with respect focus in order to cover a radiation field size of a meter in diameter. At the beam output were added aluminum filtration in order to reproduce qualities of narrow beams N-40 (E{sub efective} = 33 keV), N-80 (E{sub efective} = 65 keV) and N-100 (E{sub efective} = 83 keV) according to the ISO standard 4037 (1-3). Each lead apron were fixed 10 TLD dosimeters over its surface, 5 dosimeters before and 5 dosimeters after with respect to X-ray beam and were calibrated for Harshaw 4500 thermoluminescent reader system order to assess the attenuation of each apron. Were performed dosimeters readings and were calculated the attenuation coefficients for each effective energy of X-ray quality. In order to confirm the method of effective energy of ISO-4037 and evaluate effectiveness of lead aprons based on energy range for each medical practice was made a Monte Carlo simulation using code GEANT-4, calculating the fluence and absorbed dose in each one of the dosimeters Monte Carlo, then coefficients of linear attenuation were calculated and compared with the experimental data and reported by the National Institute of Standards and Technology (Nist). Finally, results are consistent between theoretical calculation and experimental measures. This work will serve to make assessments for other personalized leaded protections. (Author)

  17. Assessment of the effectiveness of attenuation of leaded aprons through TLD dosimetry and Monte Carlo simulation method

    International Nuclear Information System (INIS)

    Olaya D, H.; Diaz M, J. A.; Martinez O, S. A.; Vega C, H. R.

    2016-10-01

    Were performed experimental setups using an X-ray equipment continuous emission Pantak DXT-3000 and three types of leaded aprons with thickness of 0.25, 0.5 and 0.75 mm coated with Mylar Fiber coated Mylar on its surface. Apron was located at a distance of 2.5 m with respect focus in order to cover a radiation field size of a meter in diameter. At the beam output were added aluminum filtration in order to reproduce qualities of narrow beams N-40 (E_e_f_e_c_t_i_v_e = 33 keV), N-80 (E_e_f_e_c_t_i_v_e = 65 keV) and N-100 (E_e_f_e_c_t_i_v_e = 83 keV) according to the ISO standard 4037 (1-3). Each lead apron were fixed 10 TLD dosimeters over its surface, 5 dosimeters before and 5 dosimeters after with respect to X-ray beam and were calibrated for Harshaw 4500 thermoluminescent reader system order to assess the attenuation of each apron. Were performed dosimeters readings and were calculated the attenuation coefficients for each effective energy of X-ray quality. In order to confirm the method of effective energy of ISO-4037 and evaluate effectiveness of lead aprons based on energy range for each medical practice was made a Monte Carlo simulation using code GEANT-4, calculating the fluence and absorbed dose in each one of the dosimeters Monte Carlo, then coefficients of linear attenuation were calculated and compared with the experimental data and reported by the National Institute of Standards and Technology (Nist). Finally, results are consistent between theoretical calculation and experimental measures. This work will serve to make assessments for other personalized leaded protections. (Author)

  18. Analisis Penerapan Lean Production Process untuk Mengurangi Lead Time Process Perawatan Engine (Studi Kasus PT.GMF AEROASIA

    Directory of Open Access Journals (Sweden)

    Wahyu Adrianto

    2016-04-01

    Full Text Available Engine maintenance strives to always improve its service excellence with tools such as gate system where the system is expected to realize the lead time for 60days. In the implementation of the gate system is still not able to meet the expected target. During maintenance or overhaul the engine is still encountered waste or waste that causes the target cannot be met. Lean Manufacturing is an approach that aims to minimize waste that occurs in the process flow.Understanding the conditions of the process described in Value Stream Mapping for further elaborate activities that have the value-added and non-value added.Through seven waste concept, then be weighted to determine the most dominant type of waste.From the data processing is obtained that through the Value Stream Mapping is known gate 1 and gate 3 is the point that there are many wastes. Weighting and ranking of seven existing waste in the process of the activity obtained results in the form of a waste critical sequence of seven existing waste. Highest weights on the type of waste waiting with a weight of 0.38. Results of Root Cause Analysis in mind that the root cause of waste waiting for that data is maintained, the lack of attention to people development, There are still bugs in the system and miscommunication.

  19. Contaminant Characteristics and Health Risk Assessment of Heavy Metals in Soils from Lead-Zincs Melting Plant in Huize County, Yunnan Province, China

    Directory of Open Access Journals (Sweden)

    LIU Xiao-yan

    2016-05-01

    Full Text Available In order to explore history environmental problems of lead-zinc smelting, Huize County, Yunnan Province, forty-two surface soil samples were collected randomly from 14 sampling sites surrounding lead-zinc smelting plant. Heavy metals(Cr, Cu, Mn, Ni, Pb, Zn, Cd, As and Hg in all samples were determined by inductively coupled plasma-optical emission spectroscopy and atomic fluorescence spectrophotometer. Contamination characteristics of heavy metals in soils were observed on the basis of background values of comprehensive pollution index method. Potential risk was evaluated by using the geoaccumulation index(Igeo, potential ecological risk index(RI and health risk assessment method. The results indicated that the average concentrations of Cr, Cu, Mn, Ni, Pb, Zn, Cd, As and Hg were 92.25, 226.81, 1 567.45, 65.16, 394.66, 1 451.63, 11.16, 43.81, 0.47 mg·kg-1, respectively. Based on the Environmental Quality Standard for Soil, the multiple super scale of Cd concentration was highest, more than 274 times. According to the Igeo, Cd ranged from partial severity to serious degree. The RI indicated that the soils around lead-zinc smelting plant were at the serious ecological hazard level. Health risk assessment showed that Pb and Cd in soils surrounding old site had potential health risk to children.

  20. Health risk assessment of lead for children in tinfoil manufacturing and e-waste recycling areas of Zhejiang Province, China

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Xiaofeng [Zhejiang Provincial Center for Disease Control and Prevention, 630 Xin Cheng Road, Binjiang District, Hangzhou 310051 (China); Centre for Environment and Population Health, Griffith School of Environment, Griffith University, 170 Kessels Road, Nathan, QLD 4111 (Australia); Miller, Greg [Centre for Environment and Population Health, Griffith School of Environment, Griffith University, 170 Kessels Road, Nathan, QLD 4111 (Australia); Ding, Gangqiang; Lou, Xiaoming; Cai, Delei; Chen, Zhijian; Meng, Jia; Tang, Jun [Zhejiang Provincial Center for Disease Control and Prevention, 630 Xin Cheng Road, Binjiang District, Hangzhou 310051 (China); Chu, Cordia [Centre for Environment and Population Health, Griffith School of Environment, Griffith University, 170 Kessels Road, Nathan, QLD 4111 (Australia); Mo, Zhe; Han, Jianlong [Zhejiang Provincial Center for Disease Control and Prevention, 630 Xin Cheng Road, Binjiang District, Hangzhou 310051 (China)

    2012-06-01

    Tinfoil manufacturing and electronic waste (e-waste) recycling remain rudimentary processes in Zhejing Province, China, which could account for elevated blood lead levels (BLLs) and health impacts on children. We assessed the potential health risks of lead in tinfoil manufacturing and e-waste recycling areas. 329 children in total aged 11-12 who lived in a tinfoil manufacturing area (Lanxi), an e-waste recycling area (Luqiao) and a reference area (Chun'an) were studied. Lead levels in children's blood were determined by inductively coupled plasma mass spectrometer (ICP-MS). Blood urea nitrogen (BUN), serum creatinine, serum calcium, {delta}-Aminolaevulinic acid ({delta}-ALA) and intelligence quotient (IQ) were also measured. Geometric mean of BLLs in Lanxi, Luqiao and Chun'an were 8.11 {mu}g/dL, 6.97 {mu}g/dL, and 2.78 {mu}g/dL respectively, with 35.1%, 38.9% and 0% of children who had BLLs above 10 {mu}g/dL. The BLLs in exposed areas were much higher than those in the control area. Lanxi children had higher creatinine and calcium than Chun'an children, and Luqiao children had higher {delta}-ALA and lower calcium than Chun'an children. No significant differences of IQ were observed between Lanxi, Luqiao and Chun'an, however a negative relationship between BLLs and IQ was shown for the study children. The results indicated that lead pollution from e-waste recycling and tinfoil processing appears to be a potential serious threat to children's health. - Highlights: Black-Right-Pointing-Pointer No report on tinfoil processing impact on children's health before. Black-Right-Pointing-Pointer Few studies reported health impacts of lead from e-waste processing. Black-Right-Pointing-Pointer Children with blood lead levels < 10 {mu}g/dL are associated with a decrease in IQ. Black-Right-Pointing-Pointer Threshold appears to exist at blood lead level of about 20 {mu}g/dL for urinary {delta}-ALA.

  1. Health risk assessment of lead for children in tinfoil manufacturing and e-waste recycling areas of Zhejiang Province, China

    International Nuclear Information System (INIS)

    Wang, Xiaofeng; Miller, Greg; Ding, Gangqiang; Lou, Xiaoming; Cai, Delei; Chen, Zhijian; Meng, Jia; Tang, Jun; Chu, Cordia; Mo, Zhe; Han, Jianlong

    2012-01-01

    Tinfoil manufacturing and electronic waste (e-waste) recycling remain rudimentary processes in Zhejing Province, China, which could account for elevated blood lead levels (BLLs) and health impacts on children. We assessed the potential health risks of lead in tinfoil manufacturing and e-waste recycling areas. 329 children in total aged 11–12 who lived in a tinfoil manufacturing area (Lanxi), an e-waste recycling area (Luqiao) and a reference area (Chun'an) were studied. Lead levels in children's blood were determined by inductively coupled plasma mass spectrometer (ICP-MS). Blood urea nitrogen (BUN), serum creatinine, serum calcium, δ-Aminolaevulinic acid (δ-ALA) and intelligence quotient (IQ) were also measured. Geometric mean of BLLs in Lanxi, Luqiao and Chun'an were 8.11 μg/dL, 6.97 μg/dL, and 2.78 μg/dL respectively, with 35.1%, 38.9% and 0% of children who had BLLs above 10 μg/dL. The BLLs in exposed areas were much higher than those in the control area. Lanxi children had higher creatinine and calcium than Chun'an children, and Luqiao children had higher δ-ALA and lower calcium than Chun'an children. No significant differences of IQ were observed between Lanxi, Luqiao and Chun'an, however a negative relationship between BLLs and IQ was shown for the study children. The results indicated that lead pollution from e-waste recycling and tinfoil processing appears to be a potential serious threat to children's health. - Highlights: ► No report on tinfoil processing impact on children's health before. ► Few studies reported health impacts of lead from e-waste processing. ► Children with blood lead levels < 10 μg/dL are associated with a decrease in IQ. ► Threshold appears to exist at blood lead level of about 20 μg/dL for urinary δ-ALA.

  2. Design of a mixed-oxide fuel assembly to be assessed as a lead test assembly in a BWR reactor

    International Nuclear Information System (INIS)

    Hernandez, H.; Alonso, G.

    2001-01-01

    The open and the close cycle are the two alternatives to pursue during power generation. The reprocessing is a mature process that now shows a more competitive economic aspect, making it more attractive than ever. Mexico has not decided what to do with the existing and future depleted fuel assemblies that will be generated from the power operation, thus the direct disposal and the reprocessing are still being considered. To have enough arguments in one or the other alternatives it is necessary to make an assessment of both. This investigation focus in the MOX fuel design assuming that the reprocessing is the option to follow and looking for the lowest impact in power generation. The first step in a reprocessing program is to analyze the performance of four lead test assemblies (LTA's), thus in this investigation we design the corresponding MOX to be used as LTA's and assess their performance through one operational cycle. (author)

  3. Lead isotope ratios in lichen samples evaluated by ICP-ToF-MS to assess possible atmospheric pollution sources in Havana, Cuba.

    Science.gov (United States)

    Alvarez, Alfredo Montero; Estévez Alvarez, Juan R; do Nascimento, Clístenes Williams Araújo; González, Iván Pupo; Rizo, Oscar Díaz; Carzola, Lázaro Lima; Torres, Roberto Ayllón; Pascual, Jorge Gómez

    2017-01-01

    Epiphytic lichens, collected from 119 sampling sites grown over "Roistonea Royal Palm" trees, were used to assess the spatial distribution pattern of lead (Pb) and identify possible pollution sources in Havana (Cuba). Lead concentrations in lichens and topsoils were determined by flame atomic absorption spectrophotometry and inductively coupled plasma (ICP) atomic emission spectrometry, respectively, while Pb in crude oils and gasoline samples were measured by ICP-time of flight mass spectrometry (ICP-ToF-MS). Lead isotopic ratios measurements for lichens, soils, and crude oils were obtained by ICP-ToF-MS. We found that enrichment factors (EF) reflected a moderate contamination for 71% of the samples (EF > 10). The 206 Pb/ 207 Pb ratio values for lichens ranged from 1.17 to 1.20 and were a mixture of natural radiogenic and industrial activities (e.g., crude oils and fire plants). The low concentration of Pb found in gasoline (leaded gasoline is no longer used in Cuba.

  4. A real-time assessment of factors influencing medication events.

    Science.gov (United States)

    Dollarhide, Adrian W; Rutledge, Thomas; Weinger, Matthew B; Fisher, Erin Stucky; Jain, Sonia; Wolfson, Tanya; Dresselhaus, Timothy R

    2014-01-01

    Reducing medical error is critical to improving the safety and quality of healthcare. Physician stress, fatigue, and excessive workload are performance-shaping factors (PSFs) that may influence medical events (actual administration errors and near misses), but direct relationships between these factors and patient safety have not been clearly defined. This study assessed the real-time influence of emotional stress, workload, and sleep deprivation on self-reported medication events by physicians in academic hospitals. During an 18-month study period, 185 physician participants working at four university-affiliated teaching hospitals reported medication events using a confidential reporting application on handheld computers. Emotional stress scores, perceived workload, patient case volume, clinical experience, total sleep, and demographic variables were also captured via the handheld computers. Medication event reports (n = 11) were then correlated with these demographic and PSFs. Medication events were associated with 36.1% higher perceived workload (p sleep (p = .10). These results confirm the effect of factors influencing medication events, and support attention to both provider and hospital environmental characteristics for improving patient safety. © 2013 National Association for Healthcare Quality.

  5. Assessing the performance under ionising radiation of lead tungstate scintillators for EM calorimetry in the CLAS12 Forward Tagger

    Science.gov (United States)

    Fegan, S.; Auffray, E.; Battaglieri, M.; Buchanan, E.; Caiffi, B.; Celentano, A.; Colaneri, L.; D`Angelo, A.; De Vita, R.; Dormenev, V.; Fanchini, E.; Lanza, L.; Novotny, R. W.; Parodi, F.; Rizzo, A.; Sokhan, D.; Tarasov, I.; Zonta, I.

    2015-07-01

    The well-established technology of electromagnetic calorimetry using Lead Tungstate crystals has recently seen an upheaval, with the closure of one of the most experienced large-scale suppliers of such crystals, the Bogoroditsk Technical Chemical Plant (BTCP), which was instrumental in the development of mass production procedures for PWO-II, the current benchmark for this scintillator. Obtaining alternative supplies of Lead Tungstate crystals matching the demanding specifications of contemporary calorimeter devices now presents a significant challenge to detector research and development programmes. In this paper we describe a programme of assessment carried out for the selection, based upon the performance under irradiation, of Lead Tungstate crystals for use in the Forward Tagger device, part of the CLAS12 detector in Hall B at Jefferson Lab. The crystals tested were acquired from SICCAS, the Shanghai Institute of Ceramics, Chinese Academy of Sciences. The tests performed are intended to maximise the performance of the detector within the practicalities of the crystal manufacturing process. Results of light transmission, before and after gamma ray irradiation, are presented and used to calculate dk, the induced radiation absorption coefficient, at 420 nm, the peak of the Lead Tungstate emission spectrum. Results for the SICCAS crystals are compared with identical measurements carried out on Bogoroditsk samples, which were acquired for the Forward Tagger development program before the closure of the facility. Also presented are a series of tests performed to determine the feasibility of recovering radiation damage to the crystals using illumination from an LED, with such illumination available in the Forward Tagger from a light monitoring system integral to the detector.

  6. Assessing the performance under ionising radiation of lead tungstate scintillators for EM calorimetry in the CLAS12 Forward Tagger

    Energy Technology Data Exchange (ETDEWEB)

    Fegan, S., E-mail: fegan@ge.infn.it [Istituto Nazionale di Fisica Nucleare, Sezione di Genova and Dipartimento di Fisica dell' Universitá, Via Dodecaneso 33, 16146 Genova (Italy); Auffray, E. [CERN, European Organisation for Nuclear Research, Geneva (Switzerland); Battaglieri, M. [Istituto Nazionale di Fisica Nucleare, Sezione di Genova and Dipartimento di Fisica dell' Universitá, Via Dodecaneso 33, 16146 Genova (Italy); Buchanan, E. [University of Glasgow, Glasgow G12 8QQ (United Kingdom); Caiffi, B.; Celentano, A. [Istituto Nazionale di Fisica Nucleare, Sezione di Genova and Dipartimento di Fisica dell' Universitá, Via Dodecaneso 33, 16146 Genova (Italy); Colaneri, L.; D' Angelo, A. [Istituto Nazionale di Fisica Nucleare, Sezione Roma2 Tor Vergata and Università degli studi di Roma Tor Vergata, Via Scientifica 1, 00133 Roma (Italy); De Vita, R. [Istituto Nazionale di Fisica Nucleare, Sezione di Genova and Dipartimento di Fisica dell' Universitá, Via Dodecaneso 33, 16146 Genova (Italy); Dormenev, V. [II. Physikalisches Institut, Universität Gießen, 35392 Gießen (Germany); Fanchini, E. [Istituto Nazionale di Fisica Nucleare, Sezione di Genova and Dipartimento di Fisica dell' Universitá, Via Dodecaneso 33, 16146 Genova (Italy); Lanza, L. [Istituto Nazionale di Fisica Nucleare, Sezione Roma2 Tor Vergata and Università degli studi di Roma Tor Vergata, Via Scientifica 1, 00133 Roma (Italy); Novotny, R.W. [II. Physikalisches Institut, Universität Gießen, 35392 Gießen (Germany); and others

    2015-07-21

    The well-established technology of electromagnetic calorimetry using Lead Tungstate crystals has recently seen an upheaval, with the closure of one of the most experienced large-scale suppliers of such crystals, the Bogoroditsk Technical Chemical Plant (BTCP), which was instrumental in the development of mass production procedures for PWO-II, the current benchmark for this scintillator. Obtaining alternative supplies of Lead Tungstate crystals matching the demanding specifications of contemporary calorimeter devices now presents a significant challenge to detector research and development programmes. In this paper we describe a programme of assessment carried out for the selection, based upon the performance under irradiation, of Lead Tungstate crystals for use in the Forward Tagger device, part of the CLAS12 detector in Hall B at Jefferson Lab. The crystals tested were acquired from SICCAS, the Shanghai Institute of Ceramics, Chinese Academy of Sciences. The tests performed are intended to maximise the performance of the detector within the practicalities of the crystal manufacturing process. Results of light transmission, before and after gamma ray irradiation, are presented and used to calculate dk, the induced radiation absorption coefficient, at 420 nm, the peak of the Lead Tungstate emission spectrum. Results for the SICCAS crystals are compared with identical measurements carried out on Bogoroditsk samples, which were acquired for the Forward Tagger development program before the closure of the facility. Also presented are a series of tests performed to determine the feasibility of recovering radiation damage to the crystals using illumination from an LED, with such illumination available in the Forward Tagger from a light monitoring system integral to the detector.

  7. Estimates of over-diagnosis of breast cancer due to population-based mammography screening in South Australia after adjustment for lead time effects.

    Science.gov (United States)

    Beckmann, Kerri; Duffy, Stephen W; Lynch, John; Hiller, Janet; Farshid, Gelareh; Roder, David

    2015-09-01

    To estimate over-diagnosis due to population-based mammography screening using a lead time adjustment approach, with lead time measures based on symptomatic cancers only. Women aged 40-84 in 1989-2009 in South Australia eligible for mammography screening. Numbers of observed and expected breast cancer cases were compared, after adjustment for lead time. Lead time effects were modelled using age-specific estimates of lead time (derived from interval cancer rates and predicted background incidence, using maximum likelihood methods) and screening sensitivity, projected background breast cancer incidence rates (in the absence of screening), and proportions screened, by age and calendar year. Lead time estimates were 12, 26, 43 and 53 months, for women aged 40-49, 50-59, 60-69 and 70-79 respectively. Background incidence rates were estimated to have increased by 0.9% and 1.2% per year for invasive and all breast cancer. Over-diagnosis among women aged 40-84 was estimated at 7.9% (0.1-12.0%) for invasive cases and 12.0% (5.7-15.4%) when including ductal carcinoma in-situ (DCIS). We estimated 8% over-diagnosis for invasive breast cancer and 12% inclusive of DCIS cancers due to mammography screening among women aged 40-84. These estimates may overstate the extent of over-diagnosis if the increasing prevalence of breast cancer risk factors has led to higher background incidence than projected. © The Author(s) 2015.

  8. Time factor in e-learning and assessment

    OpenAIRE

    Romero Velasco, Margarida

    2010-01-01

    Peer-reviewed Peer reviewed Time is probably one of the most polysemous words in education. In e-learning, characterization of the time factor is particularly relevant because of the high level of flexibility in the teaching and learning times, and the resulting responsibility of the e-learners in regulating their learning times.

  9. Exposure time independent summary statistics for assessment of drug dependent cell line growth inhibition.

    Science.gov (United States)

    Falgreen, Steffen; Laursen, Maria Bach; Bødker, Julie Støve; Kjeldsen, Malene Krag; Schmitz, Alexander; Nyegaard, Mette; Johnsen, Hans Erik; Dybkær, Karen; Bøgsted, Martin

    2014-06-05

    In vitro generated dose-response curves of human cancer cell lines are widely used to develop new therapeutics. The curves are summarised by simplified statistics that ignore the conventionally used dose-response curves' dependency on drug exposure time and growth kinetics. This may lead to suboptimal exploitation of data and biased conclusions on the potential of the drug in question. Therefore we set out to improve the dose-response assessments by eliminating the impact of time dependency. First, a mathematical model for drug induced cell growth inhibition was formulated and used to derive novel dose-response curves and improved summary statistics that are independent of time under the proposed model. Next, a statistical analysis workflow for estimating the improved statistics was suggested consisting of 1) nonlinear regression models for estimation of cell counts and doubling times, 2) isotonic regression for modelling the suggested dose-response curves, and 3) resampling based method for assessing variation of the novel summary statistics. We document that conventionally used summary statistics for dose-response experiments depend on time so that fast growing cell lines compared to slowly growing ones are considered overly sensitive. The adequacy of the mathematical model is tested for doxorubicin and found to fit real data to an acceptable degree. Dose-response data from the NCI60 drug screen were used to illustrate the time dependency and demonstrate an adjustment correcting for it. The applicability of the workflow was illustrated by simulation and application on a doxorubicin growth inhibition screen. The simulations show that under the proposed mathematical model the suggested statistical workflow results in unbiased estimates of the time independent summary statistics. Variance estimates of the novel summary statistics are used to conclude that the doxorubicin screen covers a significant diverse range of responses ensuring it is useful for biological

  10. Health risk assessment of various metal(loid)s via multiple exposure pathways on children living near a typical lead-acid battery plant, China

    International Nuclear Information System (INIS)

    Cao, Suzhen; Duan, Xiaoli; Zhao, Xiuge; Wang, Beibei; Ma, Jin; Fan, Delong; Sun, Chengye; He, Bin; Wei, Fusheng; Jiang, Guibin

    2015-01-01

    Manufacture of lead-acid batteries is of widespread interest because of its emissions of heavy metals and metalloids into environment, harming environmental quality and consequently causing detrimental effects on human health. In this study, exposure pathways and health risks of children to heavy metal(loid)s (Pb, Cd, As, etc) were investigated based on field sampling and questionnaire. Pb was one of the most abundant elements in children's blood, with an elevated blood lead level of 12.45 μg dL −1 . Soil/dust and food were heavily polluted by targeted metal(loid)s. Food ingestion accounted for more than 80% of the total exposure for most metal(loid)s. The non-cancer risks to children were 3–10 times higher than the acceptable level of 1, while the cancer risks were 5–200 times higher than the maximum acceptable level of 1.0 × 10 −4 . The study emphasized the significance of effective environmental management, particularly to ensure food security near battery facilities. - Highlights: • The health risks of children living around a typical lead-acid battery was analyzed. • The exposure pathways of children to 12 heavy metal(loid)s were assessed. • Courtyard soil and indoor dust and duplicate food were contaminated by metal(loid)s. • Food ingestion was the major pathway for children's exposure to most metal(loid)s. • Higher potentially non-cancer and cancer risks happened to the local children. - The children living around a typical lead-acid battery plant suffered from serious health risks, which mainly attributed to food ingestion and air inhalation exposure

  11. Environmental risk assessment of lead-zinc mining: a case study of Adudu metallogenic province, middle Benue Trough, Nigeria.

    Science.gov (United States)

    Igwe, Ogbonnaya; Una, Chuku Okoro; Abu, Ezekiel; Adepehin, Ekundayo Joseph

    2017-09-07

    Assessment of the impacts of lead-zinc mining in Adudu-Imon metallogenic province was carried out. Reconnaissance and detailed field studies were done. Lithologies, stream sediments, farmland soils, mine tailings, artificial pond water, stream water, well water, and borehole water were collected and subjected to atomic absorption spectrometry (AAS) and X-ray fluorescence (XRF) analyses. Geochemical maps were generated using ArcGIS 10.1. Significant contamination with cadmium (Cd), iron (Fe), and lead (Pb) was recorded in the collected water samples. Virtually all collected soil samples were observed to be highly contaminated when compared with the European Union environmental policy standard. The discharge of mining effluents through farmlands to the Bakebu stream, which drains the area, further exposes the dwellers of this environment to the accumulation of potentially harmful metals (PHMs) in their bodies through the consumption of food crops, aquatic animals, and domestic uses of the water collected from the stream channels. The study revealed non-conformity of past mining operations in the Adudu-Imon province to existing mining laws in Nigeria. Inhabitants of this region should stop farming in the vicinity of the mines, fishing from the Bakebu stream channels should be discouraged, and domestic use of the water should be condemned, even as concerned government agencies put necessary mercenaries in place to ensure conformity of miners to standard mining regulations in Nigeria.

  12. Whole-cell bioreporters and risk assessment of environmental pollution: A proof-of-concept study using lead.

    Science.gov (United States)

    Zhang, Xiaokai; Qin, Boqiang; Deng, Jianming; Wells, Mona

    2017-10-01

    As the world burden of environmental contamination increases, it is of the utmost importance to develop streamlined approaches to environmental risk assessment in order to prioritize mitigation measures. Whole-cell biosensors or bioreporters and speciation modeling have both become of increasing interest to determine the bioavailability of pollutants, as bioavailability is increasingly in use as an indicator of risk. Herein, we examine whether bioreporter results are able to reflect expectations based on chemical reactivity and speciation modeling, with the hope to extend the research into a wider framework of risk assessment. We study a specific test case concerning the bioavailability of lead (Pb) in aqueous environments containing Pb-complexing ligands. Ligands studied include ethylene diamine tetra-acetic acid (EDTA), meso-2,3 dimercaptosuccinic acid (DMSA), leucine, methionine, cysteine, glutathione, and humic acid (HA), and we also performed experiments using natural water samples from Lake Tai (Taihu), the third largest lake in China. We find that EDTA, DMSA, cysteine, glutathione, and HA amendment significantly reduced Pb bioavailability with increasing ligand concentration according to a log-sigmoid trend. Increasing dissolved organic carbon in Taihu water also had the same effect, whereas leucine and methionine had no notable effect on bioavailability at the concentrations tested. We find that bioreporter results are in accord with the reduction of aqueous Pb 2+ that we expect from the relative complexation affinities of the different ligands tested. For EDTA and HA, for which reasonably accurate ionization and complexation constants are known, speciation modeling is in agreement with bioreporter response to within the level of uncertainty recognised as reasonable by the United States Environmental Protection Agency for speciation-based risk assessment applications. These findings represent a first step toward using bioreporter technology to streamline

  13. A Systematic Approach for Real-Time Operator Functional State Assessment

    Science.gov (United States)

    Zhang, Guangfan; Wang, Wei; Pepe, Aaron; Xu, Roger; Schnell, Thomas; Anderson, Nick; Heitkamp, Dean; Li, Jiang; Li, Feng; McKenzie, Frederick

    2012-01-01

    A task overload condition often leads to high stress for an operator, causing performance degradation and possibly disastrous consequences. Just as dangerous, with automated flight systems, an operator may experience a task underload condition (during the en-route flight phase, for example), becoming easily bored and finding it difficult to maintain sustained attention. When an unexpected event occurs, either internal or external to the automated system, the disengaged operator may neglect, misunderstand, or respond slowly/inappropriately to the situation. In this paper, we discuss an approach for Operator Functional State (OFS) monitoring in a typical aviation environment. A systematic ground truth finding procedure has been designed based on subjective evaluations, performance measures, and strong physiological indicators. The derived OFS ground truth is continuous in time compared to a very sparse estimation of OFS based on an expert review or subjective evaluations. It can capture the variations of OFS during a mission to better guide through the training process of the OFS assessment model. Furthermore, an OFS assessment model framework based on advanced machine learning techniques was designed and the systematic approach was then verified and validated with experimental data collected in a high fidelity Boeing 737 simulator. Preliminary results show highly accurate engagement/disengagement detection making it suitable for real-time applications to assess pilot engagement.

  14. Leading a Classroom Discussion: Definition, Supportive Evidence, and Measurement of the "ETS"® National Observational Teaching Examination (NOTE) Assessment Series. Research Memorandum No. RM-16-09

    Science.gov (United States)

    Witherspoon, Margaret; Sykes, Gary; Bell, Courtney

    2016-01-01

    This paper provides a description and rationale for a performance assessment of a teaching practice--leading a classroom discussion (LCD)--included in the ETS® National Observational Teaching Examination (NOTE) assessment series. In this assessment, candidates interact with a small class of virtual students represented by avatars in a…

  15. Whole-cell bioreporters and risk assessment of environmental pollution: A proof-of-concept study using lead

    International Nuclear Information System (INIS)

    Zhang, Xiaokai; Qin, Boqiang; Deng, Jianming; Wells, Mona

    2017-01-01

    As the world burden of environmental contamination increases, it is of the utmost importance to develop streamlined approaches to environmental risk assessment in order to prioritize mitigation measures. Whole-cell biosensors or bioreporters and speciation modeling have both become of increasing interest to determine the bioavailability of pollutants, as bioavailability is increasingly in use as an indicator of risk. Herein, we examine whether bioreporter results are able to reflect expectations based on chemical reactivity and speciation modeling, with the hope to extend the research into a wider framework of risk assessment. We study a specific test case concerning the bioavailability of lead (Pb) in aqueous environments containing Pb-complexing ligands. Ligands studied include ethylene diamine tetra-acetic acid (EDTA), meso-2,3 dimercaptosuccinic acid (DMSA), leucine, methionine, cysteine, glutathione, and humic acid (HA), and we also performed experiments using natural water samples from Lake Tai (Taihu), the third largest lake in China. We find that EDTA, DMSA, cysteine, glutathione, and HA amendment significantly reduced Pb bioavailability with increasing ligand concentration according to a log-sigmoid trend. Increasing dissolved organic carbon in Taihu water also had the same effect, whereas leucine and methionine had no notable effect on bioavailability at the concentrations tested. We find that bioreporter results are in accord with the reduction of aqueous Pb 2+ that we expect from the relative complexation affinities of the different ligands tested. For EDTA and HA, for which reasonably accurate ionization and complexation constants are known, speciation modeling is in agreement with bioreporter response to within the level of uncertainty recognised as reasonable by the United States Environmental Protection Agency for speciation-based risk assessment applications. These findings represent a first step toward using bioreporter technology to streamline

  16. Carded Tow Real-Time Color Assessment: A Spectral Camera-Based System

    Directory of Open Access Journals (Sweden)

    Rocco Furferi

    2016-08-01

    Full Text Available One of the most important parameters to be controlled during the production of textile yarns obtained by mixing pre-colored fibers, is the color correspondence between the manufactured yarn and a given reference, usually provided by a designer or a customer. Obtaining yarns from raw pre-colored fibers is a complex manufacturing process entailing a number of steps such as laboratory sampling, color recipe corrections, blowing, carding and spinning. Carding process is the one devoted to transform a “fuzzy mass” of tufted fibers into a regular mass of untwisted fibers, named “tow”. During this process, unfortunately, the correspondence between the color of the tow and the target one cannot be assured, thus leading to yarns whose color differs from the one used for reference. To solve this issue, the main aim of this work is to provide a system able to perform a spectral camera-based real-time measurement of a carded tow, to assess its color correspondence with a reference carded fabric and, at the same time, to monitor the overall quality of the tow during the carding process. Tested against a number of differently colored carded fabrics, the proposed system proved its effectiveness in reliably assessing color correspondence in real-time.

  17. Assessment of Nicotine Exposure From Active Human Cigarette Smoking Time

    Directory of Open Access Journals (Sweden)

    Cahours Xavier

    2017-09-01

    Full Text Available The burning of a cigarette is a series of consecutive sequences of both passive and active burnings when a smoking cycle is applied to the cigarette. A previous study, using a smoking machine, showed that cigarette nicotine yields are dependent linearly on the difference between the time of smouldering (passive burning and the time of smoking (active burning. It is predicted that the smoker’s nicotine yield increases when the intensity of smoking increases, i.e., when the time to smoke a cigarette (smoking time decreases. Note that observations made on machines might not be comparable to human behaviours. The aim of this study was to determine whether nicotine mouth-level exposure could be predicted through measurement of human smoking time. A smoking behaviour study was conducted to compare human smoking nicotine yields obtained from both filter tip analysis and the cigarette burning time model. Results showed that smokers’ exposure to the smoke depends essentially on the speed at which the cigarette is smoked. An increase in human smoking intensity, resulting in a decrease in smoking time, generates an increase in smoke exposure, whatever the puff number, puff duration, puff volume and filter ventilation (open or blocked. The association of a machine smoking yield with a corresponding smoking time, and the time taken by a consumer to smoke the cigarette would provide information on the exposure to smoke constituents in a simple and effective manner.

  18. Long-term dietary exposure to lead in young European children: Comparing a pan-European approach with a national exposure assessment

    DEFF Research Database (Denmark)

    Boon, P.E.; Te Biesebeek, J.D.; van Klaveren, J.D.

    2012-01-01

    Long-term dietary exposures to lead in young children were calculated by combining food consumption data of 11 European countries categorised using harmonised broad food categories with occurrence data on lead from different Member States (pan-European approach). The results of the assessment...... in children living in the Netherlands were compared with a long-term lead intake assessment in the same group using Dutch lead concentration data and linking the consumption and concentration data at the highest possible level of detail. Exposures obtained with the pan-European approach were higher than...... the national exposure calculations. For both assessments cereals contributed most to the exposure. The lower dietary exposure in the national study was due to the use of lower lead concentrations and a more optimal linkage of food consumption and concentration data. When a pan-European approach, using...

  19. SureCure{sup (R)}-A new material to reduces curing time and improve curing reproducibility of lead-acid batteries

    Energy Technology Data Exchange (ETDEWEB)

    Boden, David P.; Loosemore, Daniel V.; Botts, G. Dean [Hammond Lead Products Division, Hammond Group Inc., 2323 165th Street, Hammond, IN 46320 (United States)

    2006-08-25

    This paper introduces a technology that considerably reduces the time to cure the positive plates of lead-acid batteries. In each of several full-scale trials at automotive and industrial battery manufacturers, the simple replacement of 1wt.% of leady oxide with finely-divided tetrabasic lead sulfate (SureCure(TM) by Hammond Group Inc.) is shown to accelerate significantly the conversion of tribasic lead sulfate (3BS) to tetrabasic lead sulfate (4BS) in the curing process while improving crystal structure and reproducibility. Shorter curing times result in reduced labour and energy costs, as well as reduced fixed (curing chambers and plant footprint) and working (plate inventory) capital investment. (author)

  20. ARAC: A flexible real-time dose consequence assessment system

    International Nuclear Information System (INIS)

    Ellis, J.S.; Sullivan, T.J.

    1993-01-01

    Since its beginning, the Atmospheric Release Advisory Capability (ARAC), an emergency radiological dose assessment service of the US Government, has been called on to do consequence assessments for releases into the atmosphere of radionuclides and a variety of other substances. Some of the more noteworthy emergency responses have been for the Three Mile Island and Chernobyl nuclear power reactor accidents, and more recently, for a cloud of gases from a rail-car spill into the Sacramento river of the herbicide metam sodium, smoke from hundreds of burning oil wells in Kuwait, and ash clouds from the eruption of Mt. Pinatubo. The spatial scales of these responses range from local, to regional, to global, and the response periods from hours, to weeks, to months. Because of the variety of requirements of each unique assessment, ARAC has developed and maintains a flexible system of people, computer software and hardware

  1. Strategic environmental assessment in post-modern times

    International Nuclear Information System (INIS)

    Fischer, Thomas B.

    2003-01-01

    The increasing awareness of the findings of policy and decision making theory in the environmental assessment community has recently led to an intensifying debate on the theoretical foundations and the appropriate practical use of strategic environmental assessment (SEA). In this context, most of the recent suggestions on how to improve practice have been influenced--consciously or sub-consciously--by the post-modernist paradigm, focusing particularly on a better integration of SEA into 'real' decision making and procedural flexibility. There have also been suggestions that traditional project environmental impact assessment (EIA)-based SEA approaches are generally inadequate. Reacting to the latter criticism, this paper aims at defending 'traditional' systematically structured and normative approaches to SEA. While it is acknowledged that a purely professional and technological paradigm to SEA is something of the past, it is proposed that leaving the design of 'flexible' SEA to the will of proponents and stakeholders might ultimately render it incapable of protecting the environment

  2. Balancing Optimal Assessment with Part-Time Faculty Participation: A Discipline's Dilemma

    Science.gov (United States)

    Danley-Scott, Jennifer; Tompsett-Makin, Deborah

    2013-01-01

    Part-time faculty need to be brought into the student learning outcomes assessment loop not only to help accreditation, but because they, like full-time faculty, can benefit from assessment. When part-time faculty are not participating in assessment, a sizable percentage of courses are being less effectively taught than they could be. In an…

  3. Psychophysical Assessment of Timing in Individuals with Autism

    Science.gov (United States)

    Allman, Melissa J.; DeLeon, Iser G.

    2011-01-01

    Perception of time, in the seconds to minutes range, is not well characterized in autism. The required interval timing system (ITS) develops at the same stages during infancy as communication, social reciprocity, and other cognitive and behavioral functions. The authors used two versions of a temporal bisection procedure to study the perception of…

  4. Assessment of Differing Definitions of Accelerometer Nonwear Time

    Science.gov (United States)

    Evenson, Kelly R.; Terry, James W., Jr.

    2009-01-01

    Measuring physical activity with objective tools, such as accelerometers, is becoming more common. Accelerometers measure acceleration multiple times within a given frequency and summarize this as a count over a pre-specified time period or epoch. The resultant count represents acceleration over the epoch length. Accelerometers eliminate biases…

  5. Assessing the Predictability of Scheduled-Vehicle Travel Times

    DEFF Research Database (Denmark)

    Tiesyte, Dalia; Jensen, Christian Søndergaard

    2009-01-01

    One of the most desired and challenging services in collective transport systems is the real-time prediction of the near-future travel times of scheduled vehicles, especially public buses, thus improving the experience of the transportation users, who may be able to better schedule their travel......, and also enabling system operators to perform real-time monitoring. While travel-time prediction has been researched extensively during the past decade, the accuracies of existing techniques fall short of what is desired, and proposed mathematical prediction models are often not transferable to other...... systems because the properties of the travel-time-related data of vehicles are highly context-dependent, making the models difficult to fit. We propose a framework for evaluating various predictability types of the data independently of the model, and we also compare predictability analysis results...

  6. The peer-review system: time for re-assessment?

    DEFF Research Database (Denmark)

    Larsen, Poul Scheel; Riisgard, H. U.; Quinn, G

    2000-01-01

    Referees are the backbone of quality control. They need more recognition for their work. In an open exchange of opinions among a number of leading editors and experienced reviewers one suggestion has wide support: It should no longer be 'free' to submit a manuscript to a scientific journal. While...... cash payment for reviews is not considered a good idea, a 'payback in kind' system is favored: i.e., if you want to submit papers to a journal you must be willing to review for that journal....

  7. LEADING WITH LEADING INDICATORS

    International Nuclear Information System (INIS)

    PREVETTE, S.S.

    2005-01-01

    This paper documents Fluor Hanford's use of Leading Indicators, management leadership, and statistical methodology in order to improve safe performance of work. By applying these methods, Fluor Hanford achieved a significant reduction in injury rates in 2003 and 2004, and the improvement continues today. The integration of data, leadership, and teamwork pays off with improved safety performance and credibility with the customer. The use of Statistical Process Control, Pareto Charts, and Systems Thinking and their effect on management decisions and employee involvement are discussed. Included are practical examples of choosing leading indicators. A statistically based color coded dashboard presentation system methodology is provided. These tools, management theories and methods, coupled with involved leadership and employee efforts, directly led to significant improvements in worker safety and health, and environmental protection and restoration at one of the nation's largest nuclear cleanup sites

  8. Anxiety in Asperger's Syndrome: Assessment in Real Time

    Science.gov (United States)

    Hare, Dougal J.; Wood, Christopher; Wastell, Sarah; Skirrow, Paul

    2015-01-01

    Anxiety is a major problem for many people with Asperger's syndrome who may have qualitatively different fears from a non-Asperger's syndrome population. Research has relied on measures developed for non-Asperger's syndrome populations that require reporting past experiences of anxiety, which may confound assessment in people with Asperger's…

  9. Using historical photography to monitor and assess threats over time

    Science.gov (United States)

    Don. Evans

    2010-01-01

    Analysis of aerial photography is perhaps the best way to assess changes in landcover conditions. In the United States, most national forests have repeat photography on approximately a 10-year cycle. Analysis of this rich photo record can reveal changes in insect damage, fuels buildup, unmanaged off-highway vehicle use, loss of open space, and other land-cover...

  10. Time well spent? Assessing nursing-supply chain activities.

    Science.gov (United States)

    Ferenc, Jeff

    2010-02-01

    The amount of time nurses spend providing direct patient care seems to be continually eroding. So it's little wonder a survey conducted last year of critical care, OR nurses and nurse executives found that half of the 1600 respondents feel they spend too much time on supply chain duties. Most also said their supply chain duties impact patient safe ty and their ability to provide bedside care. Experts interviewed for this report believe it's time for supply chain leaders and nurses to develop a closer working partnership. Included are their recommendations to improve performance.

  11. assessment of public willingness to commit time to urban forestry

    African Journals Online (AJOL)

    DR AJEWOLE

    Time and money are very important prerequisite resources essential for participatory urban ..... Table 4 presents the results for the descriptive statistics for utility variables ..... Since Tobit coefficients do not directly give the marginal effects of the.

  12. Impact of data source on travel time reliability assessment.

    Science.gov (United States)

    2014-08-01

    Travel time reliability measures are becoming an increasingly important input to the mobility and : congestion management studies. In the case of Maryland State Highway Administration, reliability : measures are key elements in the agencys Annual ...

  13. Health risk assessment and dietary exposure of polycyclic aromatic hydrocarbons (PAHs), lead and cadmium from bread consumed in Nigeria.

    Science.gov (United States)

    Udowelle, Nnaemeka Arinze; Igweze, Zelinjo Nkeiruka; Asomugha, Rose Ngozi; Orisakwe, Orish Ebere

    A risk assessment and dietary exposure to polycyclic aromatic hydrocarbons (PAHs), lead and cadmium from bread, a common food consumed in Nigeria. Sixty samples of bread were collected from different types of bakeries where the heat is generated by wood (42 samples) or by electricity (18 samples) from twenty bakeries located in Gusau Zamfara (B1- B14) and Port Harcourt Rivers States (B15-B20) in Nigeria. PAHs in bread were determined by gas chromatography. Lead and cadmium were determined using atomic absorption spectrophotometry. Non-carcinogenic PAHs pyrene (13.72 μg/kg) and genotoxic PAHs (PAH8), benzo[a]anthracene (9.13 μg/ kg) were at the highest concentrations. Total benzo[a]pyrene concentration of 6.7 μg/kg was detected in 100% of tested samples. Dietary intake of total PAHs ranged between 0.004-0.063 μg/kg bw. day-1 (children), 0.002-0.028 μg/kg day-1 (adolescents), 0.01-0.017 μg/kg day-1 (male), 0.002-0.027 μg/kg day-1 (female), and 0.002-0.025 μg/kg day-1 (seniors). The Target Hazard Quotient (THQ) for Pb and Cd were below 1. Lead ranged from 0.01-0.071 mg/kg with 10.85 and 100% of bread samples violating the permissible limit set by USEPA, WHO and EU respectively. Cadmium ranged from 0.01-0.03 mg/kg, with all bread samples below the permissible limits as set by US EPA, JECFA and EU. The daily intake of Pb and Cd ranged from 0.03-0.23 μg/kg bw day-1 and 0.033-0.36 μg/kg bw day-1 respectively. Incremental lifetime cancer risk (ILCR) was 3.8 x 10-7. The levels of these contaminants in bread if not controlled might present a possible route of exposure to heavy metals and PAHs additional to the body burden from other sources.

  14. Innovative real time simulation training and nuclear probabilistic risk assessment

    International Nuclear Information System (INIS)

    Reisinger, M.F.

    1991-01-01

    Operator errors have been an area of public concern for the safe operation of nuclear power plants since the TMI2 incident. Simply stated, nuclear plants are very complex systems and the public is skeptical of the operators' ability to comprehend and deal with the vast indications and complexities of potential nuclear power plant events. Prior to the TMI2 incident, operator errors and human factors were not included as contributing factors in the Probabilistic Risk Assessment (PRA) studies of nuclear power plant accidents. More recent efforts in nuclear risk assessment have addressed some of the human factors affecting safe nuclear plant operations. One study found four major factors having significant impact on operator effectiveness. This paper discusses human factor PRAs, new applications in simulation training and the specific potential benefits from simulation in promoting safer operation of future power plants as well as current operating power plants

  15. Direct look from a predator shortens the risk-assessment time by prey.

    Directory of Open Access Journals (Sweden)

    Sang-im Lee

    Full Text Available Decision making process is an important component of information use by animals and has already been studied in natural situations. Decision making takes time, which is expressed as a cost in evolutionary explanations of decision making abilities of animals. However, the duration of information assessment and decision making process has not been measured in a natural situation. Here, we use responses of wild magpies (Pica pica to predictably approaching humans to demonstrate that, regardless of whether the bird perceived high (decided to fly away or low (resumed foraging threat level, the bird assessed the situation faster when approaching humans looked directly at it than when the humans were not directly looking at it. This indicates that prey is able to extract more information about the predator's intentions and to respond sooner when the predator is continuously ("intently" looking at the prey. The results generally illustrate how an increase of information available to an individual leads to a shorter assessment and decision making process, confirming one of central tenets of psychology of information use in a wild bird species in its natural habitat.

  16. AN ECOLOGICAL RISK ASSESSMENT OF LEAD SHOT EXPOSURE IN NON-WATERFOWL AVIAN SPECIES: UPLAND GAME BIRDS AND RAPTORS

    Science.gov (United States)

    There is increasing concern that birds in terrestrial ecosystems may be exposed to spent lead shot. Evidence exists that upland birds, particularly mourning doves (Zenaida macroura), ingest spent lead shot and that raptors ingest lead shot by consuming wounded game. Mortality, ne...

  17. Quality of cardio-pulmonary resuscitation (CPR) during paediatric resuscitation training: time to stop the blind leading the blind.

    Science.gov (United States)

    Arshid, Muhammad; Lo, Tsz-Yan Milly; Reynolds, Fiona

    2009-05-01

    Recent evidence suggested that the quality of cardio-pulmonary resuscitation (CPR) during adult advanced life support training was suboptimal. This study aimed to assess the CPR quality of a paediatric resuscitation training programme, and to determine whether it was sufficiently addressed by the trainee team leaders during training. CPR quality of 20 consecutive resuscitation scenario training sessions was audited prospectively using a pre-designed proforma. A consultant intensivist and a senior nurse who were also Advanced Paediatric Life Support (APLS) instructors assessed the CPR quality which included ventilation frequency, chest compression rate and depth, and any unnecessary interruption in chest compressions. Team leaders' response to CPR quality and elective change of compression rescuer during training were also recorded. Airway patency was not assessed in 13 sessions while ventilation rate was too fast in 18 sessions. Target compression rate was not achieved in only 1 session. The median chest compression rate was 115 beats/min. Chest compressions were too shallow in 10 sessions and were interrupted unnecessarily in 13 sessions. More than 50% of training sessions did not have elective change of the compression rescuer. 19 team leaders failed to address CPR quality during training despite all team leaders being certified APLS providers. The quality of CPR performance was suboptimal during paediatric resuscitation training and team leaders-in-training had little awareness of this inadequacy. Detailed CPR quality assessment and feedback should be integrated into paediatric resuscitation training to ensure optimal performance in real life resuscitations.

  18. Risk assessment of pet-traded decapod crustaceans in the Republic of Kazakhstan, the leading country in Central Asia

    Directory of Open Access Journals (Sweden)

    Uderbayev Talgat

    2017-01-01

    Full Text Available The pet trade with decapod crustaceans has been considered one of the main pathway of introduction of these animals worldwide. As the leading markets in this regards are the Czech Republic, Germany and the USA. Central Asia is not perceived as an important market with ornamental decapod crustaceans. Despite this assumption, we found at least 16 species of freshwater shrimp, crayfish and crab species pet-traded in the Republic of Kazakhstan, the largest country in this region. Considering computed risk assessment, the origin of particular species, their availability on the market, the probability of establishment and further aspects, we identified two crayfish Procambarus clarkii and Procambarus fallax f. virginalis being the seriously hazardous taxa with high potential to threaten native crayfish species as well as inhabited ecosystems. To prevent their introductions and to minimize the risks of mentioned species, similarly as in the case of European Union, we recommend the total ban of import, trade and keeping of these high-risk taxa within Central Asia.

  19. Determining soil enzyme activities for the assessment of fungi and citric acid-assisted phytoextraction under cadmium and lead contamination.

    Science.gov (United States)

    Mao, Liang; Tang, Dong; Feng, Haiwei; Gao, Yang; Zhou, Pei; Xu, Lurong; Wang, Lumei

    2015-12-01

    Microorganism or chelate-assisted phytoextraction is an effective remediation tool for heavy metal polluted soil, but investigations into its impact on soil microbial activity are rarely reported. Consequently, cadmium (Cd)- and lead (Pb)-resistant fungi and citric acid (CA) were introduced to enhance phytoextraction by Solanum nigrum L. under varied Cd and Pb pollution levels in a greenhouse pot experiment. We then determined accumulation of Cd and Pb in S. nigrum and the soil enzyme activities of dehydrogenase, phosphatase, urease, catalase, sucrase, and amylase. Detrended canonical correspondence analysis (DCCA) was applied to assess the interactions between remediation strategies and soil enzyme activities. Results indicated that the addition of fungi, CA, or their combination enhanced the root biomass of S. nigrum, especially at the high-pollution level. The combined treatment of CA and fungi enhanced accumulation of Cd about 22-47 % and of Pb about 13-105 % in S. nigrum compared with the phytoextraction alone. However, S. nigrum was not shown to be a hyperaccumulator for Pb. Most enzyme activities were enhanced after remediation. The DCCA ordination graph showed increasing enzyme activity improvement by remediation in the order of phosphatase, amylase, catalase, dehydrogenase, and urease. Responses of soil enzyme activities were similar for both the addition of fungi and that of CA. In summary, results suggest that fungi and CA-assisted phytoextraction is a promising approach to restoring heavy metal polluted soil.

  20. Assessment of lead pollution in topsoils of a southern Italy area: Analysis of urban and peri-urban environment.

    Science.gov (United States)

    Guagliardi, Ilaria; Cicchella, Domenico; De Rosa, Rosanna; Buttafuoco, Gabriele

    2015-07-01

    Exposure to lead (Pb) may affect adversely human health. Mapping soil Pb contents is essential to obtain a quantitative estimate of potential risk of Pb contamination. The main aim of this paper was to determine the soil Pb concentrations in the urban and peri-urban area of Cosenza-Rende to map their spatial distribution and assess the probability that soil Pb concentration exceeds a critical threshold that might cause concern for human health. Samples were collected at 149 locations from residual and non-residual topsoil in gardens, parks, flower-beds, and agricultural fields. Fine earth fraction of soil samples was analyzed by X-ray Fluorescence spectrometry. Stochastic images generated by the sequential Gaussian simulation were jointly combined to calculate the probability of exceeding the critical threshold that could be used to delineate the potentially risky areas. Results showed areas in which Pb concentration values were higher to the Italian regulatory values. These polluted areas were quite large and likely, they could create a significant health risk for human beings and vegetation in the near future. The results demonstrated that the proposed approach can be used to study soil contamination to produce geochemical maps, and identify hot-spot areas for soil Pb concentration. Copyright © 2015. Published by Elsevier B.V.

  1. In situ remediation and phytotoxicity assessment of lead-contaminated soil by biochar-supported nHAP.

    Science.gov (United States)

    Yang, Zhangmei; Fang, Zhanqiang; Tsang, Pokeung Eric; Fang, Jianzhang; Zhao, Dongye

    2016-11-01

    In this study, a kind of biochar-supported nano-hydroxyapatite (nHAP@BC) material was used in in-situ remediation of lead-contaminated soil. Column experiments were performed to compare the mobility of nHAP@BC and Bare-nHAP. The immobilization, accumulation and toxic effects of Pb in the after-amended soil were assessed by the in vitro toxicity tests and pot experiments. The column experiments showed a significant improvement in the mobility of nHAP@BC. The immobilization rate of Pb in the soil was 74.8% after nHAP@BC remediation. Sequential extraction procedures revealed that the residual fraction of Pb increased by 66.6% after nHAP@BC remediation, which greatly reduced the bioavailability of Pb in the soil. In addition, pot experiments indicated that nHAP@BC could effectively reduce the upward translocation capacity of Pb in a soil-plant system. The concentration of Pb in the aerial part of the cabbage mustard was 0.1 mg/kg, which is lower than the tolerance limit (0.3 mg/kg). nHAP@BC can remediate Pb-contaminated soil effectively, which can restore soil quality for planting. Copyright © 2016 Elsevier Ltd. All rights reserved.

  2. Assessment of perceptual diffuseness in the time domain

    DEFF Research Database (Denmark)

    Garcia, Julian Martinez-Villalba; Jeong, Cheol-Ho; Brunskog, Jonas

    2017-01-01

    This study proposes a numerical and experimental framework for evaluating the perceptual aspect of the diffuse field condition with intended final use in music auditoria. Multiple Impulse Responses are simulated based on the time domain Poisson process with increasing reflection density. Different...

  3. Real-time traveler information market assessment white paper.

    Science.gov (United States)

    2010-02-22

    This report takes a multi-modal look at the lay of the land of the real-time traveler information : market in the United States. This includes identification and characterization of the gaps in the : domestic industry with respect to data cover...

  4. Assessing air quality in Aksaray with time series analysis

    Science.gov (United States)

    Kadilar, Gamze Özel; Kadilar, Cem

    2017-04-01

    Sulphur dioxide (SO2) is a major air pollutant caused by the dominant usage of diesel, petrol and fuels by vehicles and industries. One of the most air-polluted city in Turkey is Aksaray. Hence, in this study, the level of SO2 is analyzed in Aksaray based on the database monitored at air quality monitoring station of Turkey. Seasonal Autoregressive Integrated Moving Average (SARIMA) approach is used to forecast the level of SO2 air quality parameter. The results indicate that the seasonal ARIMA model provides reliable and satisfactory predictions for the air quality parameters and expected to be an alternative tool for practical assessment and justification.

  5. Assessment of Time Functions for Piles Driven in Clay

    DEFF Research Database (Denmark)

    Augustesen, Anders; Andersen, Lars; Sørensen, Carsten Steen

    The vertical bearing capacity of piles situated in clay is studied with regard to the long-term set-up. A statistical analysis is carried out on the basis of data from numerous static loading tests. The database covers a wide range of both soil and pile properties, which ensures a general....... Hence, it is suggested that a constant set-up factor should be applied for the prediction of pile capacities at a given time after initial driving....

  6. Preliminary assessment of air quality for sulphur dioxide, nitrogen dioxide, nitrogen oxides, particulate matter, and lead in the Netherlands under European legislation

    NARCIS (Netherlands)

    Breugel PB van; Buijsman E; LLO

    2001-01-01

    The current air quality in the Netherlands for sulphur dioxide, nitrogen dioxide, nitrogen oxides, particulate matter and lead has been assessed in the context of limit values, margins of tolerance and the assessment thresholds used in the first daughter directive for air quality of the European

  7. Selection of monitoring times to assess remediation performance

    Energy Technology Data Exchange (ETDEWEB)

    Kueper, B.H.; Mundle, K. [Queen' s Univ., Kingston, ON (Canada). Dept. of Civil Engineering, Geoengineering Centre

    2007-07-01

    Several factors determine the time needed for a plume to respond to non-aqueous phase liquid (NAPL) source zone remediation. Most spills of NAPLs (fuels, chlorinated solvents, PCB oils, creosote and coal tar) require mass removal in order to implement remediation technologies such as chemical oxidation, thermal treatments, alcohol flushing, surfactant flushing and hydraulic displacement. While much attention has been given to the development of these remediation technologies, little attention has been given to the response of the plume downstream of the treatment zone and selection of an appropriate monitoring time scale to adequately evaluate the impacts of remediation. For that reason, this study focused on the prevalence of diffusive sinks, the mobility of the contaminant and the hydraulic conductivity of subsurface materials. Typically, plumes in subsurface environments dominated by diffusive sinks or low permeability materials need long periods of time to detach after source removal. This paper presented generic plume response model simulations that illustrated concentration rebound following the use of in-situ chemical oxidation in fractured clay containing trichloroethylene. It was determined that approximately 2 years are needed to reach peak rebound concentration after cessation remedial action. It was concluded that downgradient monitoring well concentrations may be greatly reduced during remedial action due to the fact that oxidant occupies the fracture and because oxidant diffuses into the clay matrix, creating a short period of contaminant reduction in the area of flowing groundwater. 9 refs., 2 tabs., 7 figs.

  8. Selection of monitoring times to assess remediation performance

    International Nuclear Information System (INIS)

    Kueper, B.H.; Mundle, K.

    2007-01-01

    Several factors determine the time needed for a plume to respond to non-aqueous phase liquid (NAPL) source zone remediation. Most spills of NAPLs (fuels, chlorinated solvents, PCB oils, creosote and coal tar) require mass removal in order to implement remediation technologies such as chemical oxidation, thermal treatments, alcohol flushing, surfactant flushing and hydraulic displacement. While much attention has been given to the development of these remediation technologies, little attention has been given to the response of the plume downstream of the treatment zone and selection of an appropriate monitoring time scale to adequately evaluate the impacts of remediation. For that reason, this study focused on the prevalence of diffusive sinks, the mobility of the contaminant and the hydraulic conductivity of subsurface materials. Typically, plumes in subsurface environments dominated by diffusive sinks or low permeability materials need long periods of time to detach after source removal. This paper presented generic plume response model simulations that illustrated concentration rebound following the use of in-situ chemical oxidation in fractured clay containing trichloroethylene. It was determined that approximately 2 years are needed to reach peak rebound concentration after cessation remedial action. It was concluded that downgradient monitoring well concentrations may be greatly reduced during remedial action due to the fact that oxidant occupies the fracture and because oxidant diffuses into the clay matrix, creating a short period of contaminant reduction in the area of flowing groundwater. 9 refs., 2 tabs., 7 figs

  9. Effect of a real-time tele-transmission system of 12-lead electrocardiogram on the first-aid for athletes with ST-elevation myocardial infarction.

    Science.gov (United States)

    Zhang, Huan; Song, Donghan; An, Lina

    2016-05-01

    To study the effect of a real-time tele-transmission system of 12-lead electrocardiogram on door-to-balloon time in athletes with ST-elevation myocardial infarction. A total of 60 athletes with chest pain diagnosed as ST-elevation myocardial infarction (STEMI) from our hospital were randomly divided into group A (n=35) and group B (n=25), the patients in group A transmitted the real-time tele-transmission system of 12-lead electrocardiogram to the chest pain center before arriving in hospital, however, the patients in group B not. The median door-to-balloon time was significant shorter in-group A than group B (38min vs 94 min, p0.05). The median length of stay was significant reduced in-group A (5 days vs 7 days, pelectrocardiogram is beneficial to the pre-hospital diagnosis of STEMI.

  10. Ensemble hydrological forecast efficiency evolution over various issue dates and lead-time: case study for the Cheboksary reservoir (Volga River)

    Science.gov (United States)

    Gelfan, Alexander; Moreido, Vsevolod

    2017-04-01

    Ensemble hydrological forecasting allows for describing uncertainty caused by variability of meteorological conditions in the river basin for the forecast lead-time. At the same time, in snowmelt-dependent river basins another significant source of uncertainty relates to variability of initial conditions of the basin (snow water equivalent, soil moisture content, etc.) prior to forecast issue. Accurate long-term hydrological forecast is most crucial for large water management systems, such as the Cheboksary reservoir (the catchment area is 374 000 sq.km) located in the Middle Volga river in Russia. Accurate forecasts of water inflow volume, maximum discharge and other flow characteristics are of great value for this basin, especially before the beginning of the spring freshet season that lasts here from April to June. The semi-distributed hydrological model ECOMAG was used to develop long-term ensemble forecast of daily water inflow into the Cheboksary reservoir. To describe variability of the meteorological conditions and construct ensemble of possible weather scenarios for the lead-time of the forecast, two approaches were applied. The first one utilizes 50 weather scenarios observed in the previous years (similar to the ensemble streamflow prediction (ESP) procedure), the second one uses 1000 synthetic scenarios simulated by a stochastic weather generator. We investigated the evolution of forecast uncertainty reduction, expressed as forecast efficiency, over various consequent forecast issue dates and lead time. We analyzed the Nash-Sutcliffe efficiency of inflow hindcasts for the period 1982 to 2016 starting from 1st of March with 15 days frequency for lead-time of 1 to 6 months. This resulted in the forecast efficiency matrix with issue dates versus lead-time that allows for predictability identification of the basin. The matrix was constructed separately for observed and synthetic weather ensembles.

  11. Time-dependent inhibition of Na+/K+-ATPase induced by single and simultaneous exposure to lead and cadmium

    Science.gov (United States)

    Vasić, V.; Kojić, D.; Krinulović, K.; Čolović, M.; Vujačić, A.; Stojić, D.

    2007-09-01

    Time-dependent interactions of Na+/K+-ATPase, isolated from rat brain synaptic plasma membranes (SPMs), with Cd2+ and Pb2+ ions in a single exposure and in a mixture were investigated in vitro. The interference of the enzyme with these metal ions was studied as a function of different protein concentrations and exposure time. The aim of the work was to investigate the possibility of selective recognition of Cd2+ and Pb2+ ions in a mixture, on the basis of the different rates of their protein-ligand interactions. Decreasing protein concentration increased the sensitivity of Na+/K+-ATPase toward both metals. The selectivity in protein-ligand interactions was obtained by variation of preincubation time (incubation before starting the enzymatic reaction).

  12. Inventory Modelling for a Manufacturer of Sweets : An Evaluation of an Adjusted Compund Renewal Approach for B-Items With A Relative Short Production Lead Time

    NARCIS (Netherlands)

    Heuts, R.M.J.; Luijten, M.L.J.

    1999-01-01

    In this paper we are especially interested how to optimize the production/inventory control for a manufacturer of sweets, under the following circumstances: short production lead times in combination with an intermittent demand pattern for the so-called B-taste items. As for A-taste items a compound

  13. Bronchoscopic assessment of airway retention time of aerosolized xylitol

    Science.gov (United States)

    Durairaj, Lakshmi; Neelakantan, Srividya; Launspach, Janice; Watt, Janet L; Allaman, Margaret M; Kearney, William R; Veng-Pedersen, Peter; Zabner, Joseph

    2006-01-01

    Background Human airway surface liquid (ASL) has abundant antimicrobial peptides whose potency increases as the salt concentration decreases. Xylitol is a 5-carbon sugar that has the ability to lower ASL salt concentration, potentially enhancing innate immunity. Xylitol was detected for 8 hours in the ASL after application in airway epithelium in vitro. We tested the airway retention time of aerosolized iso-osmotic xylitol in healthy volunteers. Methods After a screening spirometry, volunteers received 10 ml of nebulized 5% xylitol. Bronchoscopy was done at 20 minutes (n = 6), 90 minutes (n = 6), and 3 hours (n = 5) after nebulization and ASL was collected using microsampling probes, followed by bronchoalveolar lavage (BAL). Xylitol concentration was measured by nuclear magnetic resonance spectroscopy and corrected for dilution using urea concentration. Results All subjects tolerated nebulization and bronchoscopy well. Mean ASL volume recovered from the probes was 49 ± 23 μl. The mean ASL xylitol concentration at 20, 90, and 180 minutes was 1.6 ± 1.9 μg/μl, 0.6 ± 0.6 μg/μl, and 0.1 ± 0.1 μg/μl, respectively. Corresponding BAL concentration corrected for dilution was consistently lower at all time points. The terminal half-life of aerosolized xylitol obtained by the probes was 45 minutes with a mean residence time of 65 minutes in ASL. Corresponding BAL values were 36 and 50 minutes, respectively. Conclusion After a single dose nebulization, xylitol was detected in ASL for 3 hours, which was shorter than our in vitro measurement. The microsampling probe performed superior to BAL when sampling bronchial ASL. PMID:16483382

  14. The Tenebrionidae of California: A Time Sensitive Snapshot Assessment

    Directory of Open Access Journals (Sweden)

    Rolf Aalbu

    2014-06-01

    Full Text Available Due to a diversity of habitats and its geologic history, the US state of California hosts a spectacular assemblage of darkling beetle species (Coleoptera: Tenebrionidae. In addition to being part of the California Floristic Province, one of 34 global biodiversity hotspots identified by Conservation International, California also has additional areas which are parts of the Great Basin, Mojave, and Sonoran deserts. California is divided into nine floristic regions. Each region is assessed in terms of faunal composition and endemism. A “snapshot” of our present knowledge of the Tenebrionidae indicates that 447 currently recognized species, representing 108 genera, occur in California of which one hundred and ninety are endemic. California is compared to other nearby regions in diversity and endemism. An analysis of currently valid species vs a more realistic species account based on unpublished records of likely synonyms and known species yet to be described in the scientific literature is presented. The California Floristic Region, rather than other more arid parts of California, has the highest number of total and endemic species. Because of their high diversity and endemism, tenebrionids could potentially provide a valuable tool for monitoring the environment for conservation purposes.

  15. The tenebrionidae of california: a time sensitive snapshot assessment.

    Science.gov (United States)

    Aalbu, Rolf L; Smith, Aaron D

    2014-01-01

    DUE TO A DIVERSITY OF HABITATS AND ITS GEOLOGIC HISTORY, THE US STATE OF CALIFORNIA HOSTS A SPECTACULAR ASSEMBLAGE OF DARKLING BEETLE SPECIES (COLEOPTERA: Tenebrionidae). In addition to being part of the California Floristic Province, one of 34 global biodiversity hotspots identified by Conservation International, California also has additional areas which are parts of the Great Basin, Mojave, and Sonoran deserts. California is divided into nine floristic regions. Each region is assessed in terms of faunal composition and endemism. A "snapshot" of our present knowledge of the Tenebrionidae indicates that 447 currently recognized species, representing 108 genera, occur in California of which one hundred and ninety are endemic. California is compared to other nearby regions in diversity and endemism. An analysis of currently valid species vs a more realistic species account based on unpublished records of likely synonyms and known species yet to be described in the scientific literature is presented. The California Floristic Region, rather than other more arid parts of California, has the highest number of total and endemic species. Because of their high diversity and endemism, tenebrionids could potentially provide a valuable tool for monitoring the environment for conservation purposes.

  16. Rate-base determination through real-time efficiency assessment

    International Nuclear Information System (INIS)

    Eckhardt, J.H.; Bishop, T.W.

    1990-01-01

    One of the main problems with nuclear power is the extremely high construction costs and long schedules for plant construction and start-up. It is unlikely that utility executives will risk their companies' financial health by committing the necessary capital resources given the prevailing uncertainties. For new nuclear plants to play a major role in preventing future electric supply shortages, the financial uncertainties associated with high construction costs must be minimized. To contain costs and maintain reasonable schedules for future plants, the utilities, vendors, the US Nuclear Regulatory Commission (NRC), and the state regulatory commissions can make specific changes. One of the key factors to reduce uncertainty and improve cost and schedule performance is for the state regulatory commissions to change the method of determining reasonable plant costs and placing those costs in the rate base. Currently, most state regulatory commissions assess the reasonableness of costs only after completion of construction, resulting in years of financial uncertainty and untimely conclusions as to what should have been done better

  17. Comparative Assessment of Blood Lead Levels of Automobile Technicians in Organised and Roadside Garages in Lagos, Nigeria

    Directory of Open Access Journals (Sweden)

    Abdulsalam Saliu

    2015-01-01

    Full Text Available Occupational exposure to lead is common among automobile technicians and constitutes 0.9% of total global health burden with a majority of cases in developing countries. The aim of this study was to determine and compare the blood lead levels of automobile technicians in roadside and organised garages in Lagos State, Nigeria. This was a comparative cross-sectional study. Data were collected using interviewer-administered questionnaires. Physical examinations were conducted and blood was analysed for lead using atomic spectrophotometery. Statistical analyses were performed to compare the median blood lead levels of each group using the independent sample (Mann-Whitney U test. Seventy-three (40.3% of the organised compared to 59 (34.3% of the roadside groups had high blood lead levels. The organised group had statistically significant higher median blood lead levels of, 66.0 µg/dL than the roadside 43.5 µg/dL (P < 0.05. There was also statistically significant association between high blood lead levels and abnormal discolouration of the mucosa of the mouth in the organised group. Automobile technicians in organised garages in Lagos have higher prevalence of elevated blood lead levels and higher median levels than the roadside group. Preventive strategies against lead exposures should be instituted by the employers and further actions should be taken to minimize exposures, improve work practices, implement engineering controls (e.g., proper ventilation, and ensure the use of personal protective equipment.

  18. Ozone time scale decomposition and trend assessment from surface observations

    Science.gov (United States)

    Boleti, Eirini; Hueglin, Christoph; Takahama, Satoshi

    2017-04-01

    Emissions of ozone precursors have been regulated in Europe since around 1990 with control measures primarily targeting to industries and traffic. In order to understand how these measures have affected air quality, it is now important to investigate concentrations of tropospheric ozone in different types of environments, based on their NOx burden, and in different geographic regions. In this study, we analyze high quality data sets for Switzerland (NABEL network) and whole Europe (AirBase) for the last 25 years to calculate long-term trends of ozone concentrations. A sophisticated time scale decomposition method, called the Ensemble Empirical Mode Decomposition (EEMD) (Huang,1998;Wu,2009), is used for decomposition of the different time scales of the variation of ozone, namely the long-term trend, seasonal and short-term variability. This allows subtraction of the seasonal pattern of ozone from the observations and estimation of long-term changes of ozone concentrations with lower uncertainty ranges compared to typical methodologies used. We observe that, despite the implementation of regulations, for most of the measurement sites ozone daily mean values have been increasing until around mid-2000s. Afterwards, we observe a decline or a leveling off in the concentrations; certainly a late effect of limitations in ozone precursor emissions. On the other hand, the peak ozone concentrations have been decreasing for almost all regions. The evolution in the trend exhibits some differences between the different types of measurement. In addition, ozone is known to be strongly affected by meteorology. In the applied approach, some of the meteorological effects are already captured by the seasonal signal and already removed in the de-seasonalized ozone time series. For adjustment of the influence of meteorology on the higher frequency ozone variation, a statistical approach based on Generalized Additive Models (GAM) (Hastie,1990;Wood,2006), which corrects for meteorological

  19. Assessment of Time Series Complexity Using Improved Approximate Entropy

    International Nuclear Information System (INIS)

    Kong De-Ren; Xie Hong-Bo

    2011-01-01

    Approximate entropy (ApEn), a measure quantifying complexity and/or regularity, is believed to be an effective method of analyzing diverse settings. However, the similarity definition of vectors based on Heaviside function may cause some problems in the validity and accuracy of ApEn. To overcome the problems, an improved approximate entropy (iApEn) based on the sigmoid function is proposed. The performance of iApEn is tested on the independent identically distributed (IID) Gaussian noise, the MIX stochastic model, the Rossler map, the logistic map, and the high-dimensional Mackey—Glass oscillator. The results show that iApEn is superior to ApEn in several aspects, including better relative consistency, freedom of parameter selection, robust to noise, and more independence on record length when characterizing time series with different complexities. (general)

  20. Exposure assessment of organochlorine pesticides, arsenic, and lead in children from the major agricultural areas in Sonora, Mexico.

    Science.gov (United States)

    Meza-Montenegro, Maria M; Valenzuela-Quintanar, Ana I; Balderas-Cortés, José J; Yañez-Estrada, Leticia; Gutiérrez-Coronado, Maria L; Cuevas-Robles, Alberto; Gandolfi, A Jay

    2013-04-01

    There is a lack of information of exposure to organochlorine pesticides (OCP) and some metals, such as lead (Pb) and arsenic (As), both of which were used as arsenicals pesticides, in children living in the major agricultural areas of Mexico. The objective of this study was to assess the exposure of children to different OCP, As, and Pb in the Yaqui and Mayo valleys of Sonora to generate population baseline levels of these toxins. A cross-sectional study was undertaken in 165 children (age 6-12 years old) from 10 communities from both valleys during 2009. Blood samples were analyzed for OCP and Pb and first morning void urine for inorganic As (InAs). All of the blood samples had detectable levels of dichlorodiphenyltrichloroethylene (p,p'-DDE) ranging from 0.25 to 10.3 μg/L. However lindane, dichlorodiphenyltrichloroethane (p,p'-DDT), aldrin, and endosulfan were detected in far less of the population (36.4, 23.6, 9.1, and 3 %, respectively). Methoxychlor and endrin were not found in any sample. The average value of Pb in this population was 3.2 μg Pb/dL (range 0.17-9.0) with 8.5 % of the samples having levels 50 μg/L were observed in 12.7 % of the samples. Our results show that is important to start a risk-reduction program to decrease exposure to these toxins in Mexican communities. In addition, the results can be used to establish the baseline levels of exposure to these toxins in this agricultural region and may be used as a reference point for regulatory agencies.

  1. Evaluation of Integrated Time-Temperature Effect in Pyrolysis Process of Historically Contaminated Soils with Cadmium (Cd) and Lead (Pb)

    OpenAIRE

    Bulmău C; Cocârță D. M.; Reșetar-Deac A. M.

    2013-01-01

    It is already known that heavy metals pollution causes important concern to human and ecosystem health. Heavy metals in soils at the European level represents 37.3% between main contaminates affecting soils (EEA, 2007). This paper illustrates results obtained in the framework of laboratory experiments concerning the evaluation of integrated time-temperature effect in pyrolysis process applied to contaminated soil by two different ways: it is about heavy metals historically contaminated soil f...

  2. Delayed self-regulation and time-dependent chemical drive leads to novel states in epigenetic landscapes

    Science.gov (United States)

    Mitra, Mithun K.; Taylor, Paul R.; Hutchison, Chris J.; McLeish, T. C. B.; Chakrabarti, Buddhapriya

    2014-01-01

    The epigenetic pathway of a cell as it differentiates from a stem cell state to a mature lineage-committed one has been historically understood in terms of Waddington's landscape, consisting of hills and valleys. The smooth top and valley-strewn bottom of the hill represent their undifferentiated and differentiated states, respectively. Although mathematical ideas rooted in nonlinear dynamics and bifurcation theory have been used to quantify this picture, the importance of time delays arising from multistep chemical reactions or cellular shape transformations have been ignored so far. We argue that this feature is crucial in understanding cell differentiation and explore the role of time delay in a model of a single-gene regulatory circuit. We show that the interplay of time-dependent drive and delay introduces a new regime where the system shows sustained oscillations between the two admissible steady states. We interpret these results in the light of recent perplexing experiments on inducing the pluripotent state in mouse somatic cells. We also comment on how such an oscillatory state can provide a framework for understanding more general feedback circuits in cell development. PMID:25165605

  3. High human exposure to lead through consumption of birds hunted with lead shot

    International Nuclear Information System (INIS)

    Johansen, P.; Asmund, G.; Riget, F.

    2004-01-01

    Lead shot contaminates the edible parts of birds so that tolerable human lead intake is exceeded. - We assess lead contamination of Greenland seabirds killed with lead shot having studied thick-billed murre and common eider, the two most important species in the diet. The lead concentration is very high in meat of eiders killed with lead shot (mean 6.1 μg/g-wet wt, 95% CL 2.1-12). This level is about 44 times higher than in drowned eiders and eight times higher than in shot murres. Analyzing whole breasts instead of sub-samples reveals about seven times higher lead levels in birds' meat. We conclude that in some cases the lead intake by Greenland bird eaters will largely exceed the FAO/WHO tolerable lead intake guideline and that lead shot is a more important source of lead in the diet than previously estimated

  4. Applying time-frequency analysis to assess cerebral autoregulation during hypercapnia.

    Directory of Open Access Journals (Sweden)

    Michał M Placek

    Full Text Available Classic methods for assessing cerebral autoregulation involve a transfer function analysis performed using the Fourier transform to quantify relationship between fluctuations in arterial blood pressure (ABP and cerebral blood flow velocity (CBFV. This approach usually assumes the signals and the system to be stationary. Such an presumption is restrictive and may lead to unreliable results. The aim of this study is to present an alternative method that accounts for intrinsic non-stationarity of cerebral autoregulation and the signals used for its assessment.Continuous recording of CBFV, ABP, ECG, and end-tidal CO2 were performed in 50 young volunteers during normocapnia and hypercapnia. Hypercapnia served as a surrogate of the cerebral autoregulation impairment. Fluctuations in ABP, CBFV, and phase shift between them were tested for stationarity using sphericity based test. The Zhao-Atlas-Marks distribution was utilized to estimate the time-frequency coherence (TFCoh and phase shift (TFPS between ABP and CBFV in three frequency ranges: 0.02-0.07 Hz (VLF, 0.07-0.20 Hz (LF, and 0.20-0.35 Hz (HF. TFPS was estimated in regions locally validated by statistically justified value of TFCoh. The comparison of TFPS with spectral phase shift determined using transfer function approach was performed.The hypothesis of stationarity for ABP and CBFV fluctuations and the phase shift was rejected. Reduced TFPS was associated with hypercapnia in the VLF and the LF but not in the HF. Spectral phase shift was also decreased during hypercapnia in the VLF and the LF but increased in the HF. Time-frequency method led to lower dispersion of phase estimates than the spectral method, mainly during normocapnia in the VLF and the LF.The time-frequency method performed no worse than the classic one and yet may offer benefits from lower dispersion of phase shift as well as a more in-depth insight into the dynamic nature of cerebral autoregulation.

  5. [Application of the data from China Total Diet Study to assess the distribution of lead exposure in different age-gender population groups].

    Science.gov (United States)

    Li, Xiaowei; Liu, Qing; Liu, Liping; Wu, Yongning

    2012-05-01

    To assess the distribution of dietary lead exposure in different age-gender groups of Chinese residents by using the data from China Total Diet Study, and combining the new risk assessment and the PTWI withdrawn by JECFA. Methods Combining the lead concentrations of dietary samples with the food consumption data from China Total Diet Study in 2007 to obtain the distribution of dietary intake and dietary source of lead in different age-gender population groups. Dietary lead exposure of different age-gender population groups in China was in the range of 48.7 -116.7 microg/d. The status of higher lead exposure in younger age groups was not optimistic, as the mean and median margins of exposure (MOE) have been less than 1.0 (0.1 - 0.3). The main sources of dietary lead were cereals and vegetables, which covering 57% of total lead exposure. Lowering the dietary lead exposure of Chinese residents is necessary, especially of infants and children.

  6. Assessing Spontaneous Combustion Instability with Nonlinear Time Series Analysis

    Science.gov (United States)

    Eberhart, C. J.; Casiano, M. J.

    2015-01-01

    Considerable interest lies in the ability to characterize the onset of spontaneous instabilities within liquid propellant rocket engine (LPRE) combustion devices. Linear techniques, such as fast Fourier transforms, various correlation parameters, and critical damping parameters, have been used at great length for over fifty years. Recently, nonlinear time series methods have been applied to deduce information pertaining to instability incipiency hidden in seemingly stochastic combustion noise. A technique commonly used in biological sciences known as the Multifractal Detrended Fluctuation Analysis has been extended to the combustion dynamics field, and is introduced here as a data analysis approach complementary to linear ones. Advancing, a modified technique is leveraged to extract artifacts of impending combustion instability that present themselves a priori growth to limit cycle amplitudes. Analysis is demonstrated on data from J-2X gas generator testing during which a distinct spontaneous instability was observed. Comparisons are made to previous work wherein the data were characterized using linear approaches. Verification of the technique is performed by examining idealized signals and comparing two separate, independently developed tools.

  7. Omnibus risk assessment via accelerated failure time kernel machine modeling.

    Science.gov (United States)

    Sinnott, Jennifer A; Cai, Tianxi

    2013-12-01

    Integrating genomic information with traditional clinical risk factors to improve the prediction of disease outcomes could profoundly change the practice of medicine. However, the large number of potential markers and possible complexity of the relationship between markers and disease make it difficult to construct accurate risk prediction models. Standard approaches for identifying important markers often rely on marginal associations or linearity assumptions and may not capture non-linear or interactive effects. In recent years, much work has been done to group genes into pathways and networks. Integrating such biological knowledge into statistical learning could potentially improve model interpretability and reliability. One effective approach is to employ a kernel machine (KM) framework, which can capture nonlinear effects if nonlinear kernels are used (Scholkopf and Smola, 2002; Liu et al., 2007, 2008). For survival outcomes, KM regression modeling and testing procedures have been derived under a proportional hazards (PH) assumption (Li and Luan, 2003; Cai, Tonini, and Lin, 2011). In this article, we derive testing and prediction methods for KM regression under the accelerated failure time (AFT) model, a useful alternative to the PH model. We approximate the null distribution of our test statistic using resampling procedures. When multiple kernels are of potential interest, it may be unclear in advance which kernel to use for testing and estimation. We propose a robust Omnibus Test that combines information across kernels, and an approach for selecting the best kernel for estimation. The methods are illustrated with an application in breast cancer. © 2013, The International Biometric Society.

  8. Modeling and simulation of blast-induced, early-time intracranial wave physics leading to traumatic brain injury.

    Energy Technology Data Exchange (ETDEWEB)

    Ford, Corey C. (University of New Mexico, Albuquerque, NM); Taylor, Paul Allen

    2008-02-01

    The objective of this modeling and simulation study was to establish the role of stress wave interactions in the genesis of traumatic brain injury (TBI) from exposure to explosive blast. A high resolution (1 mm{sup 3} voxels), 5 material model of the human head was created by segmentation of color cryosections from the Visible Human Female dataset. Tissue material properties were assigned from literature values. The model was inserted into the shock physics wave code, CTH, and subjected to a simulated blast wave of 1.3 MPa (13 bars) peak pressure from anterior, posterior and lateral directions. Three dimensional plots of maximum pressure, volumetric tension, and deviatoric (shear) stress demonstrated significant differences related to the incident blast geometry. In particular, the calculations revealed focal brain regions of elevated pressure and deviatoric (shear) stress within the first 2 milliseconds of blast exposure. Calculated maximum levels of 15 KPa deviatoric, 3.3 MPa pressure, and 0.8 MPa volumetric tension were observed before the onset of significant head accelerations. Over a 2 msec time course, the head model moved only 1 mm in response to the blast loading. Doubling the blast strength changed the resulting intracranial stress magnitudes but not their distribution. We conclude that stress localization, due to early time wave interactions, may contribute to the development of multifocal axonal injury underlying TBI. We propose that a contribution to traumatic brain injury from blast exposure, and most likely blunt impact, can occur on a time scale shorter than previous model predictions and before the onset of linear or rotational accelerations traditionally associated with the development of TBI.

  9. Florentino Ariza's Loneliness Which Leads Into Self-Actualization in Love in the TIME of Cholera Movie

    OpenAIRE

    Andro, Nobertus Riko Juni

    2013-01-01

    Loneliness is the condition when one lack of social relationship, particularly love or intimate relationship. The effect of loneliness can be varied. It must be painful but for some people it is the chance to deeply know about them so that they can achieve self actualization.Love In The Time Of Cholera is the film dealing mostly with loneliness issues. It tells about a man who is loyal to wait for his lover , Fermina Daza. In waiting his lover he suffers from loneliness yet he wants to be a r...

  10. Quasiparticle recombination time in superconducting lead and the quasiparticle nonequilibrium energy distribution of optically perturbed tin superconductors

    International Nuclear Information System (INIS)

    Jaworski, F.B.

    1978-01-01

    The effective quasiparticle recombination time in Pb superconductors was experimentally measured by optically perturbing Pb-oxide-Pb tunnel junctions. Analysis by carefully studying the optically modulated energy gap as a function of temperature determined the effective recombination time to be 2.06 x 10 - 10 T - 1/2e/sup δ//sup kT/ +- 30%. Careful studies on optically perturbed Sn-oxide-Sn tunnel junctions provide information on the quasiparticle nonequilibrium energy distribution function. Initial data compared closer with a modified heating model describing the photo-excited quasi particles rather than with an effective chemical potential model. However, an analysis of the IV characteristic of voltage-biased Sn junctions numerically unfolded the exact energy distribution from an integral equation. The results compare favorably to the theory of Chang and Scalapino, who calculate from the coupled Boltzmann kinetic equations the phonon and quasiparticle energy distributions. Lastly, a brief study describes Inelastic Electron Tunneling Spectroscopy as applied to the problem of the identification of altered DNA bases. The technique demonstrates an exciting potential application of physics to a contemporary problem in molecular biology

  11. Assessment of chronic constipation: colon transit time versus defecography

    International Nuclear Information System (INIS)

    Prokesch, R.W.; Breitenseher, M.J.; Kettenbach, J.; Herbst, F.; Maier, A.; Lechner, G.; Mahieu, P.

    1999-01-01

    Objective: The aim of this study was to determine the value of radiological colon transit time (CTT) measurements in relation to defecography (DFG) in chronically constipated patients. Materials and methods: In 30 patients with chronic constipation, total and segmental CTT was determined using radiopaque markers. In all of these patients defecography (DFG) was obtained. The patients were divided into three groups: In group I, 11 patients were classified with idiopathic constipation based on low stool frequency, normal DFG, or absence of symptoms of abnormal defecation. In group II, ten patients with rectal intussusception were diagnosed by DFG. In group III, there were nine patients with rectal prolapse or spastic pelvic floor syndrome, based on results of DFG. Results: Group I, idiopathic constipation (n=11), showed increased total CTT (mean, 93 h) and segmental CTT (right colon, 33 h (36%), left colon, 31 h (33%), rectosigmoid, 29 h (31%)). In group II, intussusception (n=10), patients had normal mean total CTT (54 h) and a relative decrease in rectosigmoid CTT (mean, 13 h (24%)). In group III (n=9), rectal prolapse (n=5) or spastic pelvic floor syndrome (n=4), patients showed elevated total (mean, 167 h) and rectosigmoidal CTT (mean, 95 h (57%)). Mean total CTT was significantly different between groups I and II and between groups II and III, and mean rectosigmoidal CTT was significantly different between all three groups (P<0.05). Conclusion: The use of total and rectosigmoidal CTT helps to identify the underlying pathophysiology of chronic constipation. Furthermore CTT helps to identify patients, who may benefit from DFG

  12. Assessment of chronic constipation: colon transit time versus defecography

    Energy Technology Data Exchange (ETDEWEB)

    Prokesch, R.W. E-mail: rupert.prokesch@univie.ac.at; Breitenseher, M.J.; Kettenbach, J.; Herbst, F.; Maier, A.; Lechner, G.; Mahieu, P

    1999-12-01

    Objective: The aim of this study was to determine the value of radiological colon transit time (CTT) measurements in relation to defecography (DFG) in chronically constipated patients. Materials and methods: In 30 patients with chronic constipation, total and segmental CTT was determined using radiopaque markers. In all of these patients defecography (DFG) was obtained. The patients were divided into three groups: In group I, 11 patients were classified with idiopathic constipation based on low stool frequency, normal DFG, or absence of symptoms of abnormal defecation. In group II, ten patients with rectal intussusception were diagnosed by DFG. In group III, there were nine patients with rectal prolapse or spastic pelvic floor syndrome, based on results of DFG. Results: Group I, idiopathic constipation (n=11), showed increased total CTT (mean, 93 h) and segmental CTT (right colon, 33 h (36%), left colon, 31 h (33%), rectosigmoid, 29 h (31%)). In group II, intussusception (n=10), patients had normal mean total CTT (54 h) and a relative decrease in rectosigmoid CTT (mean, 13 h (24%)). In group III (n=9), rectal prolapse (n=5) or spastic pelvic floor syndrome (n=4), patients showed elevated total (mean, 167 h) and rectosigmoidal CTT (mean, 95 h (57%)). Mean total CTT was significantly different between groups I and II and between groups II and III, and mean rectosigmoidal CTT was significantly different between all three groups (P<0.05). Conclusion: The use of total and rectosigmoidal CTT helps to identify the underlying pathophysiology of chronic constipation. Furthermore CTT helps to identify patients, who may benefit from DFG.

  13. Assessment of water resources in lead-zinc mined areas in Cherokee County, Kansas, and adjacent areas

    Science.gov (United States)

    Spruill, Timothy B.

    1987-01-01

    allowed oxidation of ore deposits which, on saturation with water, resulted in poor-quality water that generally contains large concentrations of sulfate and trace metals. Water from mines in the eastern area contained dissolved-solids concentrations of less than 500 mg/L (milligrams per liter), a median pH of 3.9, sulfate concentrations that ranged between 98 and 290 mg/L, and median concentrations for zinc of 37,600 micrograms/L (micrograms per liter), for lead of 240 micrograms/L, for cadmium of 180 micrograms/L, for iron of 70 micrograms/L, for manganese of 240 micrograms/L, and for silica of 15 mg/L. Water from mines in the western area contained dissolved-solids concentrations of generally more than 500 mg/L, a median pH of 6.8, sulfate concentrations that ranged between 170 and 2,150 mg/L, and median concentrations for zinc of 3,200 micrograms/L, for lead of 0 micrograms/L (minimum detection limit is 10 micrograms/L), for cadmium of 6 micrograms/L, for iron of 840 micrograms/L, for manganese of 440 micrograms/L, and for silica of 11 mg/L. No conclusive evidence of lateral migration of water from the mines into domestic well-water supplies in the shallow aquifer was found in the study area in Kansas. Analyses of water from public-supply wells tapping the deep aquifer did not indicate contamination with trace metals, although chemical analyses from four of six wells exhibited increasing trends through time in sulfate concentrations. These increases probably reflect localized leakage of water from the shallow aquifer along corroded or leaky well casings. Effects of abandoned lead and zinc mines on tributaries of the Spring River in the eastern area are most severe in Short Creek. Compared with water samples from three other major streams in the eastern area, a sample collected from Short Creek, 2 miles west of Galena, Kansas, during August 1981, contained the largest concentrations of dissolved sulfate (240 mg/L), zinc (25,000 micrograms/L), ca

  14. Nonlinear Time Reversal Acoustic Method of Friction Stir Weld Assessment, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — The goal of the project is demonstration of the feasibility of Friction Stir Weld (FSW) assessment by novel Nonlinear Time Reversal Acoustic (TRA) method. Time...

  15. Assessing Change in High School Student Information Literacy Using the Tool for Real-Time Assessment of Information Literacy Skills

    Science.gov (United States)

    Kovalik, Cindy L.; Yutzey, Susan D.; Piazza, Laura M.

    2012-01-01

    Change in high school student information literacy (IL) knowledge and skills, from freshman year to senior year in high school was the focus of this quasi-experimental research project. Researchers used a free information literacy skills assessment tool entitled TRAILS (Tool for Real-time Assessment of Information Literacy Skills) to measure…

  16. Reflective (Ac) Counting: Institutional Research, Evaluation, & Assessment in a Time of Cholera

    Science.gov (United States)

    Heinecke, Walter F.

    2011-01-01

    Institutional researchers (IR) and assessment professionals in higher education are living in interesting and challenging times, one might say in times of crisis. As federal and state coffers have shrunk in a time of rising costs of higher education, university budgets are tightening while at the same time calls for accountability are increasing…

  17. Assessing the speciation pattern of lead and zinc in surface water collected from Abegede creek, Ijora and Lagos

    International Nuclear Information System (INIS)

    Adeniyi, A.A.; Okedeyi, O.O.

    2004-01-01

    A two stage sequential extraction procedure for the speciation of zinc and lead has been applied to surface water randomly collected from three sites in Abegede Creek, Ijora and Lagos. The determination of the labile and non-labile metals species was carried out by flame atomic absorption spectrophotometry (FAAS). The mean values of non-labile zinc and lead concentrations from the three sites, A, B and Care 0.54 minus plus 0.25 mg/l; 0.55 plus minus 0.26 mg/l;1.13 plus 0.76 mg/l; respectively for zinc and 0.13 plus minus 0.09 mg/l; 0.17 plus minus 0.07 mg/l;0.42 plus minus 0.23 mg/l respectively for lead. These are higher than for the labile species in the three sites;0.14 plus minus 0.07 mg/l; 0.21 plus minus 0.22 mg/l; 0.73 plus minus 0.82 mg/l, respectively for zinc and ND; 0.02 plus minus 0.04 mg/l; 0.16 plus minus 0.22 mg/l, respectively for lead. The statistical analysis of variance of the distribution of zinc and lead in the three sites were estimated at 95% confidence level. The values of metal and obtained were compared with Nigeria's background values for some rivers and the World Health Organization limits for drinking water respectively and found to be generally higher especially for lead levels. The probable sources of zinc and lead in the Creek are from natural and point sources, although there could be non-point source contributions from urban run-offs and vehicular exhaust. (author)

  18. The factor of time in the life cycle assessment of housing

    NARCIS (Netherlands)

    Klunder, G.; van Nunen, H.

    2003-01-01

    Conducting life cycle assessments, or LCAs, involves many uncertainties, including those related to the factor of time. Time is very important in the environmental assessment of housing, because of the relatively long service life of houses. During a house's service life many changes occur, which

  19. Lead poisoning

    Science.gov (United States)

    ... drinking water in homes containing pipes that were connected with lead solder . Although new building codes require ... lead in their bodies when they put lead objects in their mouths, especially if they swallow those ...

  20. Lead Poisoning

    Science.gov (United States)

    Lead is a metal that occurs naturally in the earth's crust. Lead can be found in all parts of our ... from human activities such as mining and manufacturing. Lead used to be in paint; older houses may ...

  1. The welfare of farmed mink should be easy to assess in a correct way and lead to animal welfare improvements

    DEFF Research Database (Denmark)

    Henriksen, Britt

    2015-01-01

    A three year PhD-study in assessment of mink welfare has contributed with methods and knowledge on how to get the welfare assessments as efficient and correct as possible and how to use the assessments in order to increase the welfare of the animals. The study found, that it might be possible...... periods have the same effect of date of assessment. The study also found that mink farmers are generally positive towards the structural way of working in stable schools and that including a discussion of the WelFur results related to the different farms in a stable school will make the feedback...

  2. Atmospheric deposition of trace elements around point sources and human health risk assessment. I: Impact zones around a lead source

    DEFF Research Database (Denmark)

    Moseholm, L.; Larsen, Erik Huusfeldt; Andersen, B.

    1992-01-01

    The deposition of lead was monitored over 8 years in the area around a car battery factory north of Copenhagen, Denmark. The area also has heavy traffic. Deposition was measured by in-situ grown vegetables, transplant grass culture biomonitors, bulk deposition and soil samples. Three impact zones...... were identified by a multivariate statistical analysis. Within each zone, the total dietary intake of lead was estimated for adults and children as a percentage of the provisional tolerably weekly intake (PTWI), and as a result recommendation on restrictions in use of locally grown fruit and vegetables...

  3. Assessment of cadmium, copper and lead in marine species of the atlantic and pacific oceans of Guatemala by voltametry techniques

    International Nuclear Information System (INIS)

    Chun, Evelyn

    2000-01-01

    In this thesis results of measurements of cooper, lead, and cadmium were made using voltametry. Three points in the pacific ocean and one in the atlantic were selected to obtain samples of fish and shrimp as species that are contaminated with toxic metals. The samples were treated by physical and chemical methods to turn soluble the metals and the chemical determination could be done using voltametry or differential polarography of pulse. The results shown that copper, lead and cadmium are present in the samples in traces level. The precision of measurements was verified measuring certified by the National Institute of Standard and Technology NIST of the Commerce Departmento of the United States

  4. Assessment of in situ immobilization of Lead (Pb) and Arsenic (As) in contaminated soils with phosphate and iron: solubility and bioaccessibility

    NARCIS (Netherlands)

    Cui, Y.S.; Du, X.; Weng, L.P.; Riemsdijk, van W.H.

    2010-01-01

    The effect of in situ immobilization of lead (Pb) and arsenic (As) in soil with respectively phosphate and iron is well recognized. However, studies on combined Pb and As-contaminated soil are fewer, and assessment of the effectiveness of the immobilization on mobility and bioaccessibility is also

  5. Leading Learning in Our Times

    Science.gov (United States)

    Trilling, Bernie

    2010-01-01

    Important tools that schools need to support a 21st century approach to teaching and learning include the usual suspects: the Internet, pen and paper, cell phones, educational games, tests and quizzes, good teachers, caring communities, educational funding, and loving parents. All of these items and more contribute to a 21st century education, but…

  6. BIOLOGICAL RESPONSES OF THE SEA URCHIN, ARBACIA PUNTULATA, TO LEAD CONTAMINATION FOR AN ESTUARINE ECOLOGICAL RISK ASSESSMENT

    Science.gov (United States)

    An estuarine ecological risk assessment for the Portsmouth Naval Shipyard (PNS) Kittery, ME, was conducted utilizing the U.S. EPA's Framework for Ecological Risk Assessment (ERA). As part of the analysis phase of the ERA, laboratory studies were conducted to develop quantitative ...

  7. Chinese Secondary School Students' Conceptions of Assessment and Achievement Emotions: Endorsed Purposes Lead to Positive and Negative Feelings

    Science.gov (United States)

    Chen, Junjun; Brown, Gavin T. L.

    2018-01-01

    Student perceptions of the purposes of assessment have been shown to be significant predictors of self-regulated learning. Their relationship to achievement emotions is less well understood. This paper reports a survey study of Chinese middle and high school students (N = 1,393) self-reported conceptions of the purpose of assessment and their…

  8. Combination of Didactic Lectures and Review Sessions in Endocrinology Leads to Improvement in Student Performance as Measured by Assessments

    Science.gov (United States)

    Qureshi, Ayisha; Cozine, Cassy; Rizvi, Farwa

    2013-01-01

    There can be no single best way of learning, and each teaching mode has its own merits and demerits. Didactic lectures in and of themselves are insufficient, whereas a problem-based tutorial alone can be as ineffective. This study was conducted to determine if a problem-based review after didactic lectures would lead to better student performance.…

  9. Assessment of the Potential of Honeybees (Apis mellifera L.) in Biomonitoring of Air Pollution by Cadmium, Lead and Vanadium

    NARCIS (Netherlands)

    Steen, van der J.J.M.; Kraker, de J.; Grotenhuis, J.T.C.

    2015-01-01

    The aim of our study was to explore whether honeybees (Apis mellifera L.) could be used as a reliable alternative to the standard mechanical devices for monitoring of air quality, in particular with respect to the concentration of the heavy metals cadmium (Cd), lead (Pb) and vanadium (V). We

  10. Trading Time with Space - Development of subduction zone parameter database for a maximum magnitude correlation assessment

    Science.gov (United States)

    Schaefer, Andreas; Wenzel, Friedemann

    2017-04-01

    Subduction zones are generally the sources of the earthquakes with the highest magnitudes. Not only in Japan or Chile, but also in Pakistan, the Solomon Islands or for the Lesser Antilles, subduction zones pose a significant hazard for the people. To understand the behavior of subduction zones, especially to identify their capabilities to produce maximum magnitude earthquakes, various physical models have been developed leading to a large number of various datasets, e.g. from geodesy, geomagnetics, structural geology, etc. There have been various studies to utilize this data for the compilation of a subduction zone parameters database, but mostly concentrating on only the major zones. Here, we compile the largest dataset of subduction zone parameters both in parameter diversity but also in the number of considered subduction zones. In total, more than 70 individual sources have been assessed and the aforementioned parametric data have been combined with seismological data and many more sources have been compiled leading to more than 60 individual parameters. Not all parameters have been resolved for each zone, since the data completeness depends on the data availability and quality for each source. In addition, the 3D down-dip geometry of a majority of the subduction zones has been resolved using historical earthquake hypocenter data and centroid moment tensors where available and additionally compared and verified with results from previous studies. With such a database, a statistical study has been undertaken to identify not only correlations between those parameters to estimate a parametric driven way to identify potentials for maximum possible magnitudes, but also to identify similarities between the sources themselves. This identification of similarities leads to a classification system for subduction zones. Here, it could be expected if two sources share enough common characteristics, other characteristics of interest may be similar as well. This concept

  11. Interval Timing Deficits Assessed by Time Reproduction Dual Tasks as Cognitive Endophenotypes for Attention-Deficit/Hyperactivity Disorder

    Science.gov (United States)

    Hwang-Gu, Shoou-Lian; Gau, Susan Shur-Fen

    2015-01-01

    The literature has suggested timing processing as a potential endophenotype for attention deficit/hyperactivity disorder (ADHD); however, whether the subjective internal clock speed presented by verbal estimation and limited attention capacity presented by time reproduction could be endophenotypes for ADHD is still unknown. We assessed 223 youths with DSM-IV ADHD (age range: 10-17 years), 105 unaffected siblings, and 84 typically developing (TD) youths using psychiatric interviews, intelligence tests, verbal estimation and time reproduction tasks (single task and simple and difficult dual tasks) at 5-second, 12-second, and 17-second intervals. We found that youths with ADHD tended to overestimate time in verbal estimation more than their unaffected siblings and TD youths, implying that fast subjective internal clock speed might be a characteristic of ADHD, rather than an endophenotype for ADHD. Youths with ADHD and their unaffected siblings were less precise in time reproduction dual tasks than TD youths. The magnitude of estimated errors in time reproduction was greater in youths with ADHD and their unaffected siblings than in TD youths, with an increased time interval at the 17-second interval and with increased task demands on both simple and difficult dual tasks versus the single task. Increased impaired time reproduction in dual tasks with increased intervals and task demands were shown in youths with ADHD and their unaffected siblings, suggesting that time reproduction deficits explained by limited attention capacity might be a useful endophenotype of ADHD. PMID:25992899

  12. A reengineering success story: process improvement in emergency department x-ray cycle time, leading to breakthrough performance in the ED ambulatory care (Fast Track) process.

    Science.gov (United States)

    Espinosa, J A; Treiber, P M; Kosnik, L

    1997-01-01

    This article describes the journey of a multidisciplinary reengineering team, which worked to reduce a critical, high-leverage process in an emergency department setting. The process selected was emergency department radiology services. This process was selected on a rational basis. The team knew tht 60 percent of our emergency department patients were truly ambulatory, and that most could be seen in a "fast track" process as part of our emergency department's core mission. However, we knew from customer satisfaction data, that patients would like to be "in and out" of emergency department Fast Track in less than an hour. Over half of our Fast Track patients require x-rays. For most, this was their sole reason for seeking emergency care. Our state, at the start of the project, included an average x-ray cycle time of over 60 minutes. The associated Fast-Track cycle time was over 90 minutes median. It was clear to the emergency department leadership, as well as to members of the Fast-Track management team, that a cycle time of 30 minutes or less for x-ray service was needed as a necessary condition to an hour or less Fast Track cycle time. It was also felt that a more rapid x-ray cycle time would allow for more rapid turn over of ED rooms, leading to a virtual greater capacity to the ED. It was hoped that this would lead to a reduction in the time from arrival to treatment by the emergency physician for all patients.

  13. Assessment and correction of BCC_CSM's performance in capturing leading modes of summer precipitation over North Asia

    KAUST Repository

    Gong, Zhiqiang

    2017-11-07

    This article examines the ability of Beijing Climate Center Climate System Model (BCC_CSM) in demonstrating the prediction accuracy and the leading modes of the summer precipitation over North Asia (NA). A dynamic-statistic combined approach for improving the prediction accuracy and the prediction of the leading modes of the summer precipitation over NA is proposed. Our results show that the BCC_CSM can capture part of the spatial anomaly features of the first two leading modes of NA summer precipitation. Moreover, BCC_CSM regains relationships such that the first and second mode of the empirical orthogonal function (EOF1 and EOF2) of NA summer precipitation, respectively, corresponds to the development of the El Niño and La Niña conditions in the tropical East Pacific. Nevertheless, BCC_CSM exhibits limited prediction skill over most part of NA and presents a deficiency in reproducing the EOF1\\'s and EOF2\\'s spatial pattern over central NA and EOF2\\'s interannual variability. This can be attributed as the possible reasons why the model is unable to capture the correct relationships among the basic climate elements over the central NA, lacks in its ability to reproduce a consistent zonal atmospheric pattern over NA, and has bias in predicting the relevant Sea Surface Temperature (SST) modes over the tropical Pacific and Indian Ocean regions. Based on the proposed dynamic-statistic combined correction approach, compared with the leading modes of BCC_CSM\\'s original prediction, anomaly correlation coefficients of corrected EOF1/EOF2 with the tropical Indian Ocean SST are improved from 0.18/0.36 to 0.51/0.62. Hence, the proposed correction approach suggests that the BCC_CSM\\'s prediction skill for the summer precipitation prediction over NA and its ability to capture the dominant modes could be certainly improved by choosing proper historical analogue information.

  14. Archives of Atmospheric Lead Pollution

    Science.gov (United States)

    Weiss, Dominik; Shotyk, William; Kempf, Oliver

    Environmental archives such as peat bogs, sediments, corals, trees, polar ice, plant material from herbarium collections, and human tissue material have greatly helped to assess both ancient and recent atmospheric lead deposition and its sources on a regional and global scale. In Europe detectable atmospheric lead pollution began as early as 6000years ago due to enhanced soil dust and agricultural activities, as studies of peat bogs reveal. Increased lead emissions during ancient Greek and Roman times have been recorded and identified in many long-term archives such as lake sediments in Sweden, ice cores in Greenland, and peat bogs in Spain, Switzerland, the United Kingdom, and the Netherlands. For the period since the Industrial Revolution, other archives such as corals, trees, and herbarium collections provide similar chronologies of atmospheric lead pollution, with periods of enhanced lead deposition occurring at the turn of the century and since 1950. The main sources have been industry, including coal burning, ferrous and nonferrous smelting, and open waste incineration until c.1950 and leaded gasoline use since 1950. The greatest lead emissions to the atmosphere all over Europe occurred between 1950 and 1980 due to traffic exhaust. A marked drop in atmospheric lead fluxes found in most archives since the 1980s has been attributed to the phasing out of leaded gasoline. The isotope ratios of lead in the various archives show qualitatively similar temporal changes, for example, the immediate response to the introduction and phasing out of leaded gasoline. Isotope studies largely confirm source assessments based on lead emission inventories and allow the contributions of various anthropogenic sources to be calculated.

  15. Medição e controle do tempo de atravessamento em um sistema de manufatura Measurement and control of lead-time in a manufacturing system

    Directory of Open Access Journals (Sweden)

    Miguel Afonso Sellitto

    2008-04-01

    Full Text Available Este artigo apresenta um método para a medição do tempo de atravessamento e do inventário em processo em manufatura. A medição foi usada em processo de controle organizacional de manufatura, cuja variável controlada foi o tempo de atravessamento de ordens. Tal controle pode ser útil em estratégias de manufatura em que a competição é baseada no uso do tempo, a TBC (time-based competition. Apresentou-se o método de medição, que inclui elementos da teoria das filas, e considerações para a simplificação de arranjos produtivos de manufatura. Para testar e refinar o método, estudou-se um caso em manufatura calçadista. Foram coletados dados de remessas e obtido, por análise estatística e simulação computacional, o comportamento da variável aleatória tempo de atravessamento de remessas. Como a medição foi inferior ao objetivo de desempenho, partiu-se para o controle, fazendo um diagnóstico que apontou efeitos indesejáveis observados que foram endereçados por ações corretivas implementadas. Para verificar a eficácia das ações, nova coleta foi feita. Desta vez, o objetivo de desempenho das entregas foi atendido, fechando um ciclo de controle. Os resultados foram discutidos, chegando-se a conclusões e alternativas de continuidade.This paper presents a method for the measurement of the lead-time and work-in-process in manufacturing. The measurement was used in an organizational control process in manufacturing, in which the controlled variate was the order lead-time. This kind of control can be useful in manufacture strategies formulated to compete in TBC (time-based competition. We presented the method, who includes elements from the queuing theory, and concerns about simplifying complex manufacturing arrays, in order to facilitate the analysis. In order to test and refine the method, we studied a case in a footwear manufacture system. We collected data from orders and, by statistical techniques and computational

  16. Real-time safety risk assessment based on a real-time location system for hydropower construction sites.

    Science.gov (United States)

    Jiang, Hanchen; Lin, Peng; Fan, Qixiang; Qiang, Maoshan

    2014-01-01

    The concern for workers' safety in construction industry is reflected in many studies focusing on static safety risk identification and assessment. However, studies on real-time safety risk assessment aimed at reducing uncertainty and supporting quick response are rare. A method for real-time safety risk assessment (RTSRA) to implement a dynamic evaluation of worker safety states on construction site has been proposed in this paper. The method provides construction managers who are in charge of safety with more abundant information to reduce the uncertainty of the site. A quantitative calculation formula, integrating the influence of static and dynamic hazards and that of safety supervisors, is established to link the safety risk of workers with the locations of on-site assets. By employing the hidden Markov model (HMM), the RTSRA provides a mechanism for processing location data provided by the real-time location system (RTLS) and analyzing the probability distributions of different states in terms of false positives and negatives. Simulation analysis demonstrated the logic of the proposed method and how it works. Application case shows that the proposed RTSRA is both feasible and effective in managing construction project safety concerns.

  17. Lead poisoning

    Energy Technology Data Exchange (ETDEWEB)

    Beijers, J A

    1952-01-01

    Three cases of acute lead poisoning of cattle herds via ingestion are reported, and reference is made to several other incidents of lead in both humans and animals. The quantity of lead which was found in the livers of the dead cows varied from 6.5 to 19 mg/kg, while 1160 mg/kg of lead in the liver was found for a young cow which was poisoned experimentally with 5 gms of lead acetate per day; hence, there appears to be great variability in the amounts deposited that can lead to intoxication and death. No evidence was found for a lead seam around the teeth, prophyrinuria, or basophil granules in the erythrocytes during acute or chronic lead poisoning of cattle or horses examined. Reference is made to attempts of finding the boundary line between increased lead absorption and lead intoxication in humans, and an examination of 60 laborers in an offset-printing office containing a great deal of inhalable lead (0.16 to 1.9 mg/cu m air) is reviewed. Physical deviation, basophylic granulation of erythrocytes, increased lead content of the urine, and porphyrinuria only indicate an increased absorption of lead; the use of the term intoxication is justified if, in addition, there are complaints of lack of appetite, constipation, fatigue, abdominal pain, and emaciation.

  18. Time from Symptom Debut to Dementia Assessment by the Specialist Healthcare Service in Norway

    Directory of Open Access Journals (Sweden)

    Anne-Sofie Helvik

    2018-03-01

    Full Text Available Objectives: We described the duration from symptom debut to assessment at specialist healthcare outpatient clinics for dementia in Norway and explored whether educational level was associated with time from symptom debut to dementia assessment. Methods: The study comprised 835 persons from a register for individuals with cognitive symptoms (NorCog. The outcome variable was time in months from symptom debut to assessment. The main independent variable was the number of years of education. Also age, gender, marital status, cognitive function, neuropsychiatric symptoms, assistance and location were assessed. Results: In an adjusted linear mixed model, a higher educational level was associated with a longer duration from symptom debut to assessment, where 5 additional years of education increased the time from symptom debut to consultation by 10%. Conclusion: The findings may perhaps be explained by the hypothesis that highly educated people may be able to compensate better for cognitive impairment, which is in line with a hypothesis of cognitive reserve.

  19. Time-varying surrogate data to assess nonlinearity in nonstationary time series: application to heart rate variability.

    Science.gov (United States)

    Faes, Luca; Zhao, He; Chon, Ki H; Nollo, Giandomenico

    2009-03-01

    We propose a method to extend to time-varying (TV) systems the procedure for generating typical surrogate time series, in order to test the presence of nonlinear dynamics in potentially nonstationary signals. The method is based on fitting a TV autoregressive (AR) model to the original series and then regressing the model coefficients with random replacements of the model residuals to generate TV AR surrogate series. The proposed surrogate series were used in combination with a TV sample entropy (SE) discriminating statistic to assess nonlinearity in both simulated and experimental time series, in comparison with traditional time-invariant (TIV) surrogates combined with the TIV SE discriminating statistic. Analysis of simulated time series showed that using TIV surrogates, linear nonstationary time series may be erroneously regarded as nonlinear and weak TV nonlinearities may remain unrevealed, while the use of TV AR surrogates markedly increases the probability of a correct interpretation. Application to short (500 beats) heart rate variability (HRV) time series recorded at rest (R), after head-up tilt (T), and during paced breathing (PB) showed: 1) modifications of the SE statistic that were well interpretable with the known cardiovascular physiology; 2) significant contribution of nonlinear dynamics to HRV in all conditions, with significant increase during PB at 0.2 Hz respiration rate; and 3) a disagreement between TV AR surrogates and TIV surrogates in about a quarter of the series, suggesting that nonstationarity may affect HRV recordings and bias the outcome of the traditional surrogate-based nonlinearity test.

  20. Lead Toxicity

    Science.gov (United States)

    ... o Do not use glazed ceramics, home remedies, cosmetics, or leaded-crystal glassware unless you know that they are lead safe. o If you live near an industry, mine, or waste site that may have contaminated ...

  1. Real-time Continuous Assessment Method for Mental and Physiological Condition using Heart Rate Variability

    Science.gov (United States)

    Yoshida, Yutaka; Yokoyama, Kiyoko; Ishii, Naohiro

    It is necessary to monitor the daily health condition for preventing stress syndrome. In this study, it was proposed the method assessing the mental and physiological condition, such as the work stress or the relaxation, using heart rate variability at real time and continuously. The instantanuous heart rate (HR), and the ratio of the number of extreme points (NEP) and the number of heart beats were calculated for assessing mental and physiological condition. In this method, 20 beats heart rate were used to calculate these indexes. These were calculated in one beat interval. Three conditions, which are sitting rest, performing mental arithmetic and watching relaxation movie, were assessed using our proposed algorithm. The assessment accuracies were 71.9% and 55.8%, when performing mental arithmetic and watching relaxation movie respectively. In this method, the mental and physiological condition was assessed using only 20 regressive heart beats, so this method is considered as the real time assessment method.

  2. Relational Leading

    DEFF Research Database (Denmark)

    Larsen, Mette Vinther; Rasmussen, Jørgen Gulddahl

    2015-01-01

    This first chapter presents the exploratory and curious approach to leading as relational processes – an approach that pervades the entire book. We explore leading from a perspective that emphasises the unpredictable challenges and triviality of everyday life, which we consider an interesting......, relevant and realistic way to examine leading. The chapter brings up a number of concepts and contexts as formulated by researchers within the field, and in this way seeks to construct a first understanding of relational leading....

  3. Optimal (R, Q) policy and pricing for two-echelon supply chain with lead time and retailer's service-level incomplete information

    Science.gov (United States)

    Esmaeili, M.; Naghavi, M. S.; Ghahghaei, A.

    2018-03-01

    Many studies focus on inventory systems to analyze different real-world situations. This paper considers a two-echelon supply chain that includes one warehouse and one retailer with stochastic demand and an up-to-level policy. The retailer's lead time includes the transportation time from the warehouse to the retailer that is unknown to the retailer. On the other hand, the warehouse is unaware of retailer's service level. The relationship between the retailer and the warehouse is modeled based on the Stackelberg game with incomplete information. Moreover, their relationship is presented when the warehouse and the retailer reveal their private information using the incentive strategies. The optimal inventory and pricing policies are obtained using an algorithm based on bi-level programming. Numerical examples, including sensitivity analysis of some key parameters, will compare the results between the Stackelberg models. The results show that information sharing is more beneficial to the warehouse rather than the retailer.

  4. Lead Test

    Science.gov (United States)

    ... to do renovation and repair projects using lead-safe work practices to avoid creating more lead dust or ... in a dangerous area? Yes. If you are working in a potentially harmful environment with exposure to lead dust or fumes: Wash ...

  5. Assessment of MODIS NDVI time series data products for detecting forest defoliation by gypsy moth outbreaks

    Science.gov (United States)

    Joseph P. Spruce; Steven Sader; Robert E. Ryan; James Smoot; Philip Kuper; al. et.

    2011-01-01

    This paper discusses an assessment of Moderate Resolution Imaging Spectroradiometer (MODIS) time-series data products for detecting forest defoliation from European gypsy moth (Lymantria dispar). This paper describes an effort to aid the United States Department of Agriculture (USDA) Forest Service in developing and assessing MODIS-based gypsy moth defoliation...

  6. Unsupervised deep learning for real-time assessment of video streaming services

    NARCIS (Netherlands)

    Torres Vega, M.; Mocanu, D.C.; Liotta, A.

    2017-01-01

    Evaluating quality of experience in video streaming services requires a quality metric that works in real time and for a broad range of video types and network conditions. This means that, subjective video quality assessment studies, or complex objective video quality assessment metrics, which would

  7. Endovascular aneurysm repair simulation can lead to decreased fluoroscopy time and accurately delineate the proximal seal zone.

    Science.gov (United States)

    Kim, Ann H; Kendrick, Daniel E; Moorehead, Pamela A; Nagavalli, Anil; Miller, Claire P; Liu, Nathaniel T; Wang, John C; Kashyap, Vikram S

    2016-07-01

    The use of simulators for endovascular aneurysm repair (EVAR) is not widespread. We examined whether simulation could improve procedural variables, including operative time and optimizing proximal seal. For the latter, we compared suprarenal vs infrarenal fixation endografts, right femoral vs left femoral main body access, and increasing angulation of the proximal aortic neck. Computed tomography angiography was obtained from 18 patients who underwent EVAR at a single institution. Patient cases were uploaded to the ANGIO Mentor endovascular simulator (Simbionix, Cleveland, Ohio) allowing for three-dimensional reconstruction and adapted for simulation with suprarenal fixation (Endurant II; Medtronic Inc, Minneapolis, Minn) and infrarenal fixation (C3; W. L. Gore & Associates Inc, Newark, Del) deployment systems. Three EVAR novices and three experienced surgeons performed 18 cases from each side with each device in randomized order (n = 72 simulations/participant). The cases were stratified into three groups according to the degree of infrarenal angulation: 0° to 20°, 21° to 40°, and 41° to 66°. Statistical analysis used paired t-test and one-way analysis of variance. Mean fluoroscopy time for participants decreased by 48.6% (P time decreased by 33.8% (P zone coverage in highly angulated aortic necks was significantly decreased. The infrarenal device resulted in mean aortic neck zone coverage of 91.9%, 89.4%, and 75.4% (P zone coverage. The side of femoral access for the main body did not influence proximal seal zone coverage regardless of infrarenal angulation. Simulation of EVAR leads to decreased fluoroscopy times for novice and experienced operators. Side of femoral access did not affect precision of proximal endograft landing. The angulated aortic neck leads to decreased proximal seal zone coverage regardless of infrarenal or suprarenal fixation devices. Copyright © 2016 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.

  8. Misplaced Inventory and Lead-Time in the Supply Chain: Analysis of Decision-Making on RFID Investment with Service Level

    Directory of Open Access Journals (Sweden)

    Li-Hao Zhang

    2014-01-01

    Full Text Available Radio-frequency identification (RFID, as the key technology of Internet of Things (IoT, has been hailed as a major innovation to solve misplaced inventory and reduce lead-time. Many retailers have been pushing their suppliers to invest this technology. However, its associated costs seem to prohibit its widespread application. This paper analyzes the situation of service level in a retail supply chain, which has resulted from misplaced inventory and lead-time. By newsvendor model, we analyze the difference between with- and without-RFID technologies in service level of centralized and decentralized supply chains, respectively. Then with different service levels, we determine the tag cost thresholds at which RFID technology investment becomes profitable in centralized and decentralized supply chains, respectively. Furthermore, we apply a linear transfer payment coefficient strategy to coordinate with the decentralized supply chain. It is found that whether the adoption of RFID technology improves the service level depends on the cost of RFID tag in the centralized system, but it improves the service level in the decentralized system when only the supplier bears the cost of RFID tag. Moreover, the same cost thresholds of RFID tag with different service levels exist in both the centralized and the decentralized cases.

  9. Assessment of Real-Time Time-Dependent Density Functional Theory (RT-TDDFT) in Radiation Chemistry: Ionized Water Dimer.

    Science.gov (United States)

    Chalabala, Jan; Uhlig, Frank; Slavíček, Petr

    2018-03-29

    Ionization in the condensed phase and molecular clusters leads to a complicated chain of processes with coupled electron-nuclear dynamics. It is difficult to describe such dynamics with conventional nonadiabatic molecular dynamics schemes since the number of states swiftly increases as the molecular system grows. It is therefore attractive to use a direct electron and nuclear propagation such as the real-time time-dependent density functional theory (RT-TDDFT). Here we report a RT-TDDFT benchmark study on simulations of singly and doubly ionized states of a water monomer and dimer as a prototype for more complex processes in a condensed phase. We employed the RT-TDDFT based Ehrenfest molecular dynamics with a generalized gradient approximate (GGA) functional and compared it with wave-function-based surface hopping (SH) simulations. We found that the initial dynamics of a singly HOMO ionized water dimer is similar for both the RT-TDDFT/GGA and the SH simulations but leads to completely different reaction channels on a longer time scale. This failure is attributed to the self-interaction error in the GGA functionals and it can be avoided by using hybrid functionals with large fraction of exact exchange (represented here by the BHandHLYP functional). The simulations of doubly ionized states are reasonably described already at the GGA level. This suggests that the RT-TDDFT/GGA method could describe processes following the autoionization processes such as Auger emission, while its applicability to more complex processes such as intermolecular Coulombic decay remains limited.

  10. Enhanced Requirements for Assessment in a Competency-Based, Time-Variable Medical Education System.

    Science.gov (United States)

    Gruppen, Larry D; Ten Cate, Olle; Lingard, Lorelei A; Teunissen, Pim W; Kogan, Jennifer R

    2018-03-01

    Competency-based, time-variable medical education has reshaped the perceptions and practices of teachers, curriculum designers, faculty developers, clinician educators, and program administrators. This increasingly popular approach highlights the fact that learning among different individuals varies in duration, foundation, and goal. Time variability places particular demands on the assessment data that are so necessary for making decisions about learner progress. These decisions may be formative (e.g., feedback for improvement) or summative (e.g., decisions about advancing a student). This article identifies challenges to collecting assessment data and to making assessment decisions in a time-variable system. These challenges include managing assessment data, defining and making valid assessment decisions, innovating in assessment, and modeling the considerable complexity of assessment in real-world settings and richly interconnected social systems. There are hopeful signs of creativity in assessment both from researchers and practitioners, but the transition from a traditional to a competency-based medical education system will likely continue to create much controversy and offer opportunities for originality and innovation in assessment.

  11. Assessment of atmospheric pollution in the vicinity of a tin and lead industry using lichen species Canoparmelia texana

    Energy Technology Data Exchange (ETDEWEB)

    Leonardo, Lucio, E-mail: lucioleo@ipen.br [Laboratorio de Radiometria Ambiental, Instituto de Pesquisas Energeticas e Nucleares, Av. Prof. Lineu Prestes, 2242-Sao Paulo, CEP 05508 000 (Brazil); Mazzilli, Barbara Paci; Damatto, Sandra Regina [Laboratorio de Radiometria Ambiental, Instituto de Pesquisas Energeticas e Nucleares, Av. Prof. Lineu Prestes, 2242-Sao Paulo, CEP 05508 000 (Brazil); Saiki, Mitiko [Laboratorio de Analise por Ativacao Neutronica, Instituto de Pesquisas Energeticas e Nucleares, Av. Prof. Lineu Prestes, 2242-Sao Paulo, CEP 05508 000 (Brazil); Barros de Oliveira, Sonia Maria [Departamento de Geologia Sedimentar e Ambiental, Universidade de Sao Paulo, SP (Brazil)

    2011-10-15

    This paper examines the viability of using Canoparmelia texana lichen species as a bioindicator of air pollution by radionuclides and rare earth elements (REEs) in the vicinity of a tin and lead industry. The lichen and soil samples were analyzed for uranium, thorium and REEs by instrumental neutron activation analysis. The radionuclides {sup 226}Ra, {sup 228}Ra and {sup 210}Pb were determined either by Gamma-ray spectrometry (GRS) (soils) or by radiochemical separation followed by gross alpha and beta counting using a gas flow proportional counter (lichens). The lichens samples concentrate radionuclides (on the average 25-fold higher than the background for this species) and REEs (on the average 10-fold higher), therefore they can be used as a fingerprint of contamination by the operation of the tin industry.

  12. Using lead isotopes and trace element records from two contrasting Lake Tanganyika sediment cores to assess watershed – Lake exchange

    Science.gov (United States)

    Odigie, Kingsley; Cohen, A.D.; Swarzenski, Peter W.; Flegal, R

    2014-01-01

    Lead isotopic and trace element records of two contrasting sediment cores were examined to reconstruct historic, industrial contaminant inputs to Lake Tanganyika, Africa. Observed fluxes of Co, Cu, Mn, Ni, Pb, and Zn in age-dated sediments collected from the lake varied both spatially and temporally over the past two to four centuries. The fluxes of trace elements were lower (up to 10-fold) at a mid-lake site (MC1) than at a nearshore site (LT-98-58), which is directly downstream from the Kahama and Nyasanga River watersheds and adjacent to the relatively pristine Gombe Stream National Park. Trace element fluxes at that nearshore site did not measurably change over the last two centuries (1815–1998), while the distal, mid-lake site exhibited substantial changes in the fluxes of trace elements – likely caused by changes in land use – over that period. For example, the flux of Pb increased by ∼300% from 1871 to 1991. That apparent accelerated weathering and detrital mobilization of lithogenic trace elements was further evidenced by (i) positive correlations (r = 0.77–0.99, p factors (EF operations within the lake’s watershed over the past century. The data also indicate that the mid-lake site is a much more sensitive and useful recorder of environmental changes than the nearshore site. Furthermore, the lead isotopic compositions of sediment at the sites differed spatially, indicating that the Pb (and other trace elements by association) originated from different natural sources at the two locations.

  13. Therapeutic Assessment of Complex Trauma: A Single-Case Time-Series Study

    OpenAIRE

    Tarocchi, Anna; Aschieri, Filippo; Fantini, Francesca; Smith, Justin D.

    2013-01-01

    The cumulative effect of repeated traumatic experiences in early childhood incrementally increases the risk of adjustment problems later in life. Surviving traumatic environments can lead to the development of an interrelated constellation of emotional and interpersonal symptoms termed complex posttraumatic stress disorder (CPTSD). Effective treatment of trauma begins with a multimethod psychological assessment and requires the use of several evidence-based therapeutic processes, including es...

  14. Does climate policy lead to relocation with adverse effects for GHG emissions or not? A first assessment of the spillovers of climate policy for energy intensive industry

    International Nuclear Information System (INIS)

    Oikonomou, V.; Patel, M.; Worrell, E.

    2004-12-01

    Energy-intensive industries play a special role in climate policy. World-wide, industry is responsible for about 50% of greenhouse gas emissions. The emission intensity makes these industries an important target for climate policy. At the same time these industries are particularly vulnerable if climate policy would lead to higher energy costs, and if they would be unable to offset these increased costs. The side effects of climate policy on GHG emissions in foreign countries are typically referred to as 'spillovers'. Negative spillovers reduce the effectiveness of a climate policy, while positive spillovers increase its effectiveness. This paper provides a review of the literature on the spillover effects of climate policy for carbon intensive industries. Reviews of past trends in production location of energy-intensive industries show an increased share of non-Annex 1 countries. However, this trend is primarily driven by demand growth, and there is no empirical evidence for a role of environmental policy in these development patterns. In contrast, climate models do show a strong carbon leakage of emissions from these industries. Even though that climate policy may have a more profound impact than previous environmental policies, the results of the modelling are ambiguous. The energy and carbon intensity of energy-intensive industries is rapidly declining in most developing countries, and reducing the 'gap' between industrialized and developing countries. Still, considerable potential for emission reduction exists, both in developing and industrialized countries. Technology development is likely to deliver further reductions in energy use and CO2 emissions. Despite the potential for positive spillovers in the energy-intensive industries, none of the models used in the analysis of spillovers of climate policies has an endogenous representation of technological change for the energy-intensive industries. This underlines the need for a better understanding of

  15. An Assessment of Dialysis Provider's Attitudes towards Timing of Dialysis Initiation in Canada

    Directory of Open Access Journals (Sweden)

    Bikaramjit S Mann

    2014-04-01

    Full Text Available Background: Physicians' perceptions and opinions may influence when to initiate dialysis. Objective: To examine providers' perspectives and opinions regarding the timing of dialysis initiation. Design: Online survey. Setting: Community and academic dialysis practices in Canada. Participants: A nationally-representative sample of dialysis providers. Measurements and Methods: Dialysis providers opinions assessing reasons to initiate dialysis at low or high eGFR. Responses were obtained using a 9-point Likert scale. Early dialysis was defined as initiation of dialysis in an individual with an eGFR greater than or equal to 10.5 ml/min/m 2 . A detailed survey was emailed to all members of the Canadian Society of Nephrology (CSN in February 2013. The survey was designed and pre-tested to evaluate duration and ease of administration. Results: One hundred and forty one (25% response rate physicians participated in the survey. The majority were from urban, academic centres and practiced in regionally administered renal programs. Very few respondents had a formal policy regarding the timing of dialysis initiation or formally reviewed new dialysis starts (N = 4, 3.1%. The majority of respondents were either neutral or disagreed that late compared to early dialysis initiation improved outcomes (85–88%, had a negative impact on quality of life (89%, worsened AVF or PD use (84–90%, led to sicker patients (83% or was cost effective (61%. Fifty-seven percent of respondents felt uremic symptoms occurred earlier in patients with advancing age or co-morbid illness. Half (51.8% of the respondents felt there was an absolute eGFR at which they would initiate dialysis in an asymptomatic patient. The majority of respondents would initiate dialysis for classic indications for dialysis, such as volume overload (90.1% and cachexia (83.7% however a significant number chose other factors that may lead them to early dialysis initiation including avoiding an emergency (28

  16. Prime-Time Television: Assessing Violence during the Most Popular Viewing Hours.

    Science.gov (United States)

    Smith, Stacy L.; Nathanson, Amy I.; Wilson, Barbara J.

    2002-01-01

    Assesses the prevalence and context of violence in prime-time television programming using a random, representative sample. Shows that, regardless of the time of day, viewers are likely to encounter violence in roughly 2 out of 3 programs. Identifies specific channel types and genres that feature potentially harmful depictions of violence during…

  17. Investigation of the Adaptability of Transient Stability Assessment Methods to Real-Time Operation

    DEFF Research Database (Denmark)

    Weckesser, Johannes Tilman Gabriel; Jóhannsson, Hjörtur; Sommer, Stefan

    2012-01-01

    In this paper, an investigation of the adaptability of available transient stability assessment methods to real-time operation and their real-time performance is carried out. Two approaches based on Lyapunov’s method and the equal area criterion are analyzed. The results allow to determine...

  18. A study on assessment methodology of surveillance test interval and allowed outage time

    International Nuclear Information System (INIS)

    Che, Moo Seong; Cheong, Chang Hyeon; Lee, Byeong Cheol

    1996-07-01

    The objectives of this study is the development of methodology by which assessing the optimizes Surveillance Test Interval(STI) and Allowed Outage Time(AOT) using PSA method that can supplement the current deterministic methods and the improvement of Korea nuclear power plants safety. In the first year of this study, the survey about the assessment methodologies, modeling and results performed by domestic and international researches is performed as the basic step before developing the assessment methodology of this study. The assessment methodology that supplement the revealed problems in many other studies is presented and the application of new methodology into the example system assures the feasibility of this method

  19. A study on assessment methodology of surveillance test interval and allowed outage time

    Energy Technology Data Exchange (ETDEWEB)

    Che, Moo Seong; Cheong, Chang Hyeon; Lee, Byeong Cheol [Seoul Nationl Univ., Seoul (Korea, Republic of)] (and others)

    1996-07-15

    The objectives of this study is the development of methodology by which assessing the optimizes Surveillance Test Interval(STI) and Allowed Outage Time(AOT) using PSA method that can supplement the current deterministic methods and the improvement of Korea nuclear power plants safety. In the first year of this study, the survey about the assessment methodologies, modeling and results performed by domestic and international researches is performed as the basic step before developing the assessment methodology of this study. The assessment methodology that supplement the revealed problems in many other studies is presented and the application of new methodology into the example system assures the feasibility of this method.

  20. The effectiveness of the Geritalk communication skills course: a real-time assessment of skill acquisition and deliberate practice.

    Science.gov (United States)

    Gelfman, Laura P; Lindenberger, Elizabeth; Fernandez, Helen; Goldberg, Gabrielle R; Lim, Betty B; Litrivis, Evgenia; O'Neill, Lynn; Smith, Cardinale B; Kelley, Amy S

    2014-10-01

    Communication skills are critical in Geriatrics and Palliative Medicine because these patients confront complex clinical scenarios. We evaluated the effectiveness of the Geritalk communication skills course by comparing pre- and post-course real-time assessment of the participants leading family meetings. We also evaluated the participants' sustained skills practice. We compare the participants' skill acquisition before and after Geritalk using a direct observation Family Meeting Communication Assessment Tool and assess their deliberate practice at follow-up. First-year Geriatrics or Palliative Medicine fellows at Mount Sinai Medical Center and the James J. Peters Bronx VA Medical Center participated in Geritalk. Pre- and post-course family meeting assessments were compared. An average net gain of 6.8 skills represented a greater than 20% improvement in use of applicable skills. At two month follow-up, most participants reported deliberate practice of fundamental and advanced skills. This intensive training and family meeting assessment offers evidence-based communication skills training. Published by Elsevier Inc.

  1. Toxic metals in breast milk samples from Ankara, Turkey: assessment of lead, cadmium, nickel, and arsenic levels.

    Science.gov (United States)

    Gürbay, Aylin; Charehsaz, Mohammad; Eken, Ayşe; Sayal, Ahmet; Girgin, Gözde; Yurdakök, Murat; Yiğit, Şule; Erol, Dilek Demir; Şahin, Gönül; Aydın, Ahmet

    2012-10-01

    Toxic metals are one of the significant groups of chemical contaminants that humans are exposed to by oral, inhalation, and dermal routes. Exposure to these chemicals begins with intrauterine life and continues during lactation period at the first years of life. Breastfeeding has a much more special place than other nutrition options for infants. However, when possibility of contaminant transfer by breast milk is considered, its safety and quality is essential. Regarding infant and mother health and limited number of information on this field in Turkey, measuring contamination levels in breast milk is important. Therefore, in the present study, lead (Pb), cadmium (Cd), nickel (Ni), and arsenic (As) levels were measured by atomic absorption spectrometry in 64 breast milk samples obtained from mothers from Ankara, Turkey. Pb and Ni levels in breast milk samples were found to be 391.45±269.01 μg/l and 43.94±33.82 μg/l (mean ± SD), respectively. Cd was found only in one of 64 samples, and the level was 4.62 μg/l. As level was below the limit of quantification (LOQ, 7.6 μg/l) in all samples. These findings will accurately direct strategies and solutions of protection against contaminants in order to reduce their levels in biological fluids.

  2. Real time and in situ determination of lead in road sediments using a man-portable laser-induced breakdown spectroscopy analyzer

    Energy Technology Data Exchange (ETDEWEB)

    Cunat, J.; Fortes, F.J. [Department of Analytical Chemistry, University of Malaga, E-29071 Malaga (Spain); Laserna, J.J. [Department of Analytical Chemistry, University of Malaga, E-29071 Malaga (Spain)], E-mail: laserna@uma.es

    2009-02-02

    In situ, real time levels of lead in road sediments have been measured using a man-portable laser-induced breakdown spectroscopy analyzer. The instrument consists of a backpack and a probe housing a Q-switched Nd:YAG laser head delivering 50 mJ per pulse at 1064 nm. Plasma emission was collected and transmitted via fiber optic to a compact cross Czerny-Turner spectrometer equipped with a linear CCD array allocated in the backpack together with a personal computer. The limit of detection (LOD) for lead and the precision measured in the laboratory were 190 {mu}g g{sup -1} (calculated by the 3{sigma} method) and 9% R.S.D. (relative standard deviation), respectively. During the field campaign, averaged Pb concentration in the sediments were ranging from 480 {mu}g g{sup -1} to 660 {mu}g g{sup -1} depending on the inspected area, i.e. the entrance, the central part and the exit of the tunnel. These results were compared with those obtained with flame-atomic absorption spectrometry (flame-AAS). The relative error, expressed as [100(LIBS result - flame AAS result)/(LIBS result)], was approximately 14%.

  3. Assessing error sources for Landsat time series analysis for tropical test sites in Viet Nam and Ethiopia

    Science.gov (United States)

    Schultz, Michael; Verbesselt, Jan; Herold, Martin; Avitabile, Valerio

    2013-10-01

    Researchers who use remotely sensed data can spend half of their total effort analysing prior data. If this data preprocessing does not match the application, this time spent on data analysis can increase considerably and can lead to inaccuracies. Despite the existence of a number of methods for pre-processing Landsat time series, each method has shortcomings, particularly for mapping forest changes under varying illumination, data availability and atmospheric conditions. Based on the requirements of mapping forest changes as defined by the United Nations (UN) Reducing Emissions from Forest Degradation and Deforestation (REDD) program, the accurate reporting of the spatio-temporal properties of these changes is necessary. We compared the impact of three fundamentally different radiometric preprocessing techniques Moderate Resolution Atmospheric TRANsmission (MODTRAN), Second Simulation of a Satellite Signal in the Solar Spectrum (6S) and simple Dark Object Subtraction (DOS) on mapping forest changes using Landsat time series data. A modification of Breaks For Additive Season and Trend (BFAST) monitor was used to jointly map the spatial and temporal agreement of forest changes at test sites in Ethiopia and Viet Nam. The suitability of the pre-processing methods for the occurring forest change drivers was assessed using recently captured Ground Truth and high resolution data (1000 points). A method for creating robust generic forest maps used for the sampling design is presented. An assessment of error sources has been performed identifying haze as a major source for time series analysis commission error.

  4. Will they lead by example? Assessment of vaccination rates and attitudes to human papilloma virus in millennial medical students.

    Science.gov (United States)

    Afonso, Nelia M; Kavanagh, Maurice J; Swanberg, Stephanie M; Schulte, Jeanne M; Wunderlich, Tracy; Lucia, Victoria C

    2017-01-06

    Human papillomavirus (HPV) is the most common sexually transmitted infection in the United States. It is also well established that HPV viruses are responsible for a variety of cancers. Little is known about the prevailing knowledge and attitudes toward the HPV vaccine in our future healthcare providers, a majority of whom were among the first in the target age group to receive the vaccine; the same vaccine that they will in turn be expected to recommend to their patients. The aims of this pilot study were to examine the HPV vaccination rate among medical students and determine their knowledge about HPV and attitudes toward vaccination. To aid in the development of an HPV educational intervention, a needs assessment survey was administered to discover medical students' knowledge and attitudes toward the HPV vaccine. All medical students at a Midwestern US medical school were invited to complete the survey. Two hundred fourteen of 390 medical students completed the survey with 44% having been previously vaccinated. Although 82% of all respondents believed they would recommend the vaccine to family and friends, only 40% felt knowledgeable about the vaccine and 40% felt comfortable counseling patients. More positive attitudes and better knowledge scores were found in fully vaccinated students compared to non-vaccinated students. Provider recommendation was strongly associated with HPV vaccination status. This study revealed the unique perspectives of U.S. millennial medical students as the first group of future healthcare providers to have personally encountered the HPV vaccine. Overall, students' knowledge as well as their comfort level in counseling patients was lacking. This assessment has guided the development of targeted educational interventions to address knowledge gaps and prepare students to appropriately discuss the vaccine with patients and parents and help protect young people from life threatening cancers.

  5. Will they lead by example? Assessment of vaccination rates and attitudes to human papilloma virus in millennial medical students

    Directory of Open Access Journals (Sweden)

    Nelia M. Afonso

    2017-01-01

    Full Text Available Abstract Background Human papillomavirus (HPV is the most common sexually transmitted infection in the United States. It is also well established that HPV viruses are responsible for a variety of cancers. Little is known about the prevailing knowledge and attitudes toward the HPV vaccine in our future healthcare providers, a majority of whom were among the first in the target age group to receive the vaccine; the same vaccine that they will in turn be expected to recommend to their patients. The aims of this pilot study were to examine the HPV vaccination rate among medical students and determine their knowledge about HPV and attitudes toward vaccination. Methods To aid in the development of an HPV educational intervention, a needs assessment survey was administered to discover medical students’ knowledge and attitudes toward the HPV vaccine. All medical students at a Midwestern US medical school were invited to complete the survey. Results Two hundred fourteen of 390 medical students completed the survey with 44% having been previously vaccinated. Although 82% of all respondents believed they would recommend the vaccine to family and friends, only 40% felt knowledgeable about the vaccine and 40% felt comfortable counseling patients. More positive attitudes and better knowledge scores were found in fully vaccinated students compared to non-vaccinated students. Provider recommendation was strongly associated with HPV vaccination status. Conclusions This study revealed the unique perspectives of U.S. millennial medical students as the first group of future healthcare providers to have personally encountered the HPV vaccine. Overall, students’ knowledge as well as their comfort level in counseling patients was lacking. This assessment has guided the development of targeted educational interventions to address knowledge gaps and prepare students to appropriately discuss the vaccine with patients and parents and help protect young people from

  6. Quantitative assessment of metal elements using moss species as biomonitors in downwind area of lead-zinc mine.

    Science.gov (United States)

    Balabanova, Biljana; Stafilov, Trajče; Šajn, Robert; Andonovska, Katerina Bačeva

    2017-02-23

    Distributions of a total of 21 elements were monitored in significantly lead-zinc polluted area using moss species (Hypnum cupressiforme and Camptothecium lutescens) used interchangeably, covering a denser sampling network. Interspecies comparison was conducted using Box-Cox transformed values, due to their skewed distribution. The median concentrations of trace elements in the both mosses examined decreased in the following order: Fe>Mn>Zn>Pb>Cu>Ni∼Cr∼As>Co>Cd>Hg. For almost all analyzed elements, H. cupressiforme revealed higher bio-accumulative abilities. For arsenic contents was obtained ER-value in favor of C. lutescens. The ER for the element contents according to the distance from the pollution source in selected areas was significantly enriched for the anthropogenic introduced elements As, Cd, Cu, Pb and Zn. After Box-Cox transformation of the content values, T B was significantly different for As (4.82), Cd (3.84), Cu (2.95), Pb (4.38), and Zn (4.23). Multivariate factor analysis singled out four elemental associations: F1 (Al-Co-Cr-Fe-Li-Ni-V), F2 (Cd-Pb-Zn), F3 (Ca-Mg-Na-P) and F4 (Cu) with a total variance of 89%. Spatial distribution visualized the hazardously higher contents of "hot spots" of Cd > 1.30 mg/kg, Cu > 22 mg/kg, Pb > 130 mg/kg and Zn > 160 mg/kg. Therefore, main approach in moss biomonitoring should be based on data management of the element distribution by reducing the effect of extreme values (considering Box-Cox data transformation); the interspecies variation in sampling media does not deviate in relation to H. cupressiforme vs. C. lutescens.

  7. Mortality effects assessment of ambient PM2.5 pollution in the 74 leading cities of China.

    Science.gov (United States)

    Fang, Die; Wang, Qin'geng; Li, Huiming; Yu, Yiyong; Lu, Yan; Qian, Xin

    2016-11-01

    Ambient fine particulate matter (PM2.5) pollution is currently a most severe and worrisome environmental problem in China. However, current knowledge of the health effects of this pollution is insufficient. This study aims to provide an overall understanding regarding the long-term mortality effects of current PM2.5 pollution in China and the potential health benefits of realizing the goals stipulated in the ongoing action plan of Air Pollution Prevention and Control (APPC) and the targets suggested by the WHO. Three typical causes and all-cause of PM2.5-related mortality were considered. The log-linear exposure-response function was adopted, and a meta-analysis was used to determine the exposure-response coefficients, based on newly available data in China and abroad. In the 74 leading cities of China, approximately 32% of the reported deaths, with a mortality rate of 1.9‰, were associated with PM2.5 in 2013, in which deaths from cardiovascular, respiratory and lung-cancer causes accounted for 20% of the reported deaths, with a mortality rate of 1.2‰. The regional difference is remarkable for the mortalities and proportions of the different causes. If the PM2.5 concentration goals of the APPC plan, the first interim and the guideline targets of the WHO could be achieved, the PM2.5-related all-cause mortality would be reduced by 25%, 64% and 95%, respectively, compared with that of 2013. PM2.5 pollution in China has incurred great health risks that are even worse than those of tobacco smoking. The health benefits of the APPC plan could be outstanding, although there is still great potential to improve future air quality. Copyright © 2016 Elsevier B.V. All rights reserved.

  8. A comparison between indirect and objective wear-time assessment of removable orthodontic appliances.

    Science.gov (United States)

    Schott, Timm C; Meyer-Gutknecht, Hannes; Mayer, Nicolai; Weber, Joachim; Weimer, Katja

    2017-04-01

    Patients do not always adhere to the wear times prescribed for removable orthodontic appliances. We evaluated the validity and usability of indirect wear-time assessment methods by comparing wear-time estimates with microelectronically measured wear times in patients with removable orthodontic appliances. Wear times of 33 expansion plates, 34 functional appliances, and 42 retention plates of patients aged 6-20 years (12.3±2.9 years, 50.5% female) were indirectly determined by practitioners using a questionnaire assessing five parameters on a 5-point Likert scale: appliance handling, appliance appearance, bite shift, tooth movement, and appliance fit. The perceived difficulty in assessing each parameter was rated. Actual wear times were evaluated with microelectronic sensors in the appliances. Regression analyses revealed that practitioners' decisions about wear times varied depending on the type of appliance and criteria used, with only one standard criterion best predicting estimated wear time for each appliance. Different standard criteria were better predictors of measured wear time: 22.3% of wear-time variability was explained by expansion plate appearance, 31.2% by functional appliance handling, and 18.8% by retainer fitting. However, practitioners rated the difficulty of assessment in most cases as 'easy'. The study was not double blinded for technical reasons, and practitioners may have considered the evaluation criteria more carefully than in normal daily practice. Practitioners' decisions about wear times based on standard criteria strongly vary depending on the type of appliance and criteria used. © The Author 2016. Published by Oxford University Press on behalf of the European Orthodontic Society. All rights reserved. For permissions, please email: journals.permissions@oup.com

  9. Assessment of Multivariate Neural Time Series by Phase Synchrony Clustering in a Time-Frequency-Topography Representation

    Directory of Open Access Journals (Sweden)

    M. A. Porta-Garcia

    2018-01-01

    Full Text Available Most EEG phase synchrony measures are of bivariate nature. Those that are multivariate focus on producing global indices of the synchronization state of the system. Thus, better descriptions of spatial and temporal local interactions are still in demand. A framework for characterization of phase synchrony relationships between multivariate neural time series is presented, applied either in a single epoch or over an intertrial assessment, relying on a proposed clustering algorithm, termed Multivariate Time Series Clustering by Phase Synchrony, which generates fuzzy clusters for each multivalued time sample and thereupon obtains hard clusters according to a circular variance threshold; such cluster modes are then depicted in Time-Frequency-Topography representations of synchrony state beyond mere global indices. EEG signals from P300 Speller sessions of four subjects were analyzed, obtaining useful insights of synchrony patterns related to the ERP and even revealing steady-state artifacts at 7.6 Hz. Further, contrast maps of Levenshtein Distance highlight synchrony differences between ERP and no-ERP epochs, mainly at delta and theta bands. The framework, which is not limited to one synchrony measure, allows observing dynamics of phase changes and interactions among channels and can be applied to analyze other cognitive states rather than ERP versus no ERP.

  10. Time diary and questionnaire assessment of factors associated with academic and personal success among university undergraduates.

    Science.gov (United States)

    George, Darren; Dixon, Sinikka; Stansal, Emory; Gelb, Shannon Lund; Pheri, Tabitha

    2008-01-01

    A sample of 231 students attending a private liberal arts university in central Alberta, Canada, completed a 5-day time diary and a 71-item questionnaire assessing the influence of personal, cognitive, and attitudinal factors on success. The authors used 3 success measures: cumulative grade point average (GPA), Personal Success--each participant's rating of congruence between stated goals and progress toward those goals--and Total Success--a measure that weighted GPA and Personal Success equally. The greatest predictors of GPA were time-management skills, intelligence, time spent studying, computer ownership, less time spent in passive leisure, and a healthy diet. Predictors of Personal Success scores were clearly defined goals, overall health, personal spirituality, and time-management skills. Predictors of Total Success scores were clearly defined goals, time-management skills, less time spent in passive leisure, healthy diet, waking up early, computer ownership, and less time spent sleeping. Results suggest alternatives to traditional predictors of academic success.

  11. Assessment of lead, cadmium, and zinc contamination of roadside soils, surface films, and vegetables in Kampala City, Uganda

    International Nuclear Information System (INIS)

    Nabulo, Grace; Oryem-Origa, Hannington; Diamond, Miriam

    2006-01-01

    The relationship between traffic density and trace metal concentrations in roadside soils, surface films, and a selected vegetable weed, Amaranthus dubius Mart. Ex Thell., was determined in 11 farming sites along major highways around Kampala City in Uganda. Surface soil, atmospherically deposited surface films on windows, and leaves of Amaranthus dubius were sampled at known distances from the roads and analyzed for lead (Pb), zinc (Zn), and cadmium (Cd) using flame atomic absorption spectrophotometry. Atmospherically deposited trace metal particulates were sampled using window glass as an inert, passive collector. Total trace metal concentrations in soils ranged from 30.0±2.3 to 64.6±11.7 mg/kg Pb, 78.4±18.4 to 265.6±63.2 mg/kg Zn, and 0.8±0.13 to 1.40±0.16 mg/kg Cd. Total trace metal levels in soil decreased rapidly with distance from the road. Total Pb decreased with distance up to 30 m from the road, where it reached a background soil concentration of 28 mg/kg dry weight. The study found background values of 50 and 1.4 mg/kg for Zn and Cd in roadside soils, respectively. Similarly, Pb concentration in Amaranthus dubius leaves decreased with increasing distance from the road edge. The dominant pathway for Pb contamination was from atmospheric deposition, which was consistent with Pb concentrations in surface films. The mean Pb concentrations in leaves of roadside crops were higher than those in their respective roots, with the highest leaf-to-root ratio observed in the Brassica oleraceae acephala group. The lowest Pb and Zn concentrations were found in the fruit compared to the leaves of the same crops. Leaves of roadside vegetables were therefore considered a potential source of heavy metal contamination to farmers and consumers in urban areas. It is recommended that leafy vegetables should be grown 30 m from roads in high-traffic, urban areas

  12. Concentrations of arsenic and lead in rice (Oryza sativa L.) in Iran: A systematic review and carcinogenic risk assessment.

    Science.gov (United States)

    Fakhri, Yadolah; Bjørklund, Geir; Bandpei, Anoushiravan Mohseni; Chirumbolo, Salvatore; Keramati, Hassan; Hosseini Pouya, Rokhsane; Asadi, Anvar; Amanidaz, Nazak; Sarafraz, Mansour; Sheikhmohammad, Amir; Alipour, Mohamadreza; Baninameh, Zahra; Mohseni, Seyed Mohsen; Sarkhosh, Maryam; Ghasemi, Seyed Mehdi

    2018-03-01

    Exposure to heavy metals such as arsenic (As), lead (Pb), and cadmium (Cd) in either the short or the long term can cause cancers in humans. Dietary intake and consumption of rice (Oryza sativa L.) is increasing in Iran, and several studies on the concentration of heavy metals in rice have been carried out in this country in recent years. In this perspective, the main objective of the present study was to investigate, even via a meta-analysis of the existing literature, the presence of As and Pb in rice from many geographical areas in Iran, as well as to estimate the carcinogenic risk of these heavy metals in rice consumers. The results of the present ten years-spanning systematic review indicate that 21 reports, collecting a total of 2088 samples, were performed between 2008 and October 2017. The minimum and maximum concentration of As was observed in the Golestan area (0.01 ± 0.01 mg/kg d.w) and the Gillan region (3 mg/kg d.w); and Pb in the Shahrekord (0.07 ± 0.02 mg/kg d.w) and Mazandaran (35 mg/kg d.w). The meta-analysis of data showed that pooled concentration of As in the rice was 0.04 (95%CI: 0.02-0.06 mg/kg d.w), which resulted lower than the National Standard (NS) limits. However, the pooled concentration of Pb in the rice was 0.38 (95%CI: 0.25-0.5 mg/kg d.w), i.e., higher than NS limits. The heterogeneity was significant between As (I 2  = 63%, P value = .003) and Pb (I 2  = 96%, P value rice content of As and Pb are at considerable carcinogenesis risk (ILCR > 10 -3 ). Therefore a decreased level of heavy metals in rice cultivation should be encouraged and performed in next planning. Copyright © 2018 Elsevier Ltd. All rights reserved.

  13. Leading Democratically

    Science.gov (United States)

    Brookfield, Stephen

    2010-01-01

    Democracy is the most venerated of American ideas, the one for which wars are fought and people die. So most people would probably agree that leaders should be able to lead well in a democratic society. Yet, genuinely democratic leadership is a relative rarity. Leading democratically means viewing leadership as a function or process, rather than…

  14. Assessing Lead, Nickel, and Zinc Pollution in Topsoil from a Historic Shooting Range Rehabilitated into a Public Urban Park.

    Science.gov (United States)

    Urrutia-Goyes, Ricardo; Argyraki, Ariadne; Ornelas-Soto, Nancy

    2017-06-30

    Soil contamination is a persistent problem in the world. The redevelopment of a site with a historical deposition of metals might conceal the threat of remaining pollution, especially when the site has become a public place. In this study, human health risk assessment is performed after defining the concentrations of Pb, Ni, and Zn in the topsoil of a former shooting range rehabilitated into a public park in the Municipality of Kesariani (Athens, Greece). A methodology that uses inductively coupled plasma mass spectrometry (ICP-MS, 13 samples), another that uses portable X-ray fluorescence (XRF) following a dense sample design (91 samples), and a hybrid approach that combines both, were used to obtain the concentrations of the trace elements. The enrichment factor and geoacummulation index were calculated to define the degree of pollution of the site. The hazard quotient and cancer risk indicators were also computed to find the risk to which the population is exposed. The present study reveals high non-carcinogenic health risk due to Pb pollution with ingestion as the main exposure pathway. The carcinogenic risk for Pb is within tolerable limits, but the definition of land use might alter such a statement. Lastly, regarding Ni and Zn, the site is unpolluted and there is insignificant carcinogenic and non-carcinogenic risks.

  15. Superconductivity in nanostructured lead

    Science.gov (United States)

    Lungu, Anca; Bleiweiss, Michael; Amirzadeh, Jafar; Saygi, Salih; Dimofte, Andreea; Yin, Ming; Iqbal, Zafar; Datta, Timir

    2001-01-01

    Three-dimensional nanoscale structures of lead were fabricated by electrodeposition of pure lead into artificial porous opal. The size of the metallic regions was comparable to the superconducting coherence length of bulk lead. Tc as high as 7.36 K was observed, also d Tc/d H was 2.7 times smaller than in bulk lead. Many of the characteristics of these differ from bulk lead, a type I superconductor. Irreversibility line and magnetic relaxation rates ( S) were also studied. S( T) displayed two maxima, with a peak value about 10 times smaller than that of typical high- Tc superconductors.

  16. Health risk assessment of heavy metals (cadmium, nickel, lead and zinc in withdrawed parsley vegetable from some farms in Hamedan city

    Directory of Open Access Journals (Sweden)

    M Cheraghi

    2014-11-01

    Results: Average concentration of cadmium, nickel, lead and zinc in parsley vegetable is in the order of 1/14, 2/56, 16/65 and 25/23 mg/kg and average concentration of this metals in soil is in the order of 0/23, 23/51, 20/85 and 57/5 mg/kg. Results of this study showed that average concentration of Cadmium and Leadin parsley is above WHO/FAO whereas average concentration of Nickel and Zink in parsleywas assessed less than WHO/FAO. Also the average concentration of every four metals in soil of farms was less than WHO/FAO levels.On the other hand the amount of risk and health index (HRI in parsley for lead metal was above 1 and for cadmium, nickel and zinc metals was less than 1. Conclusion: According to the studing results, cultivated parsley in this area was polluted to the heavy metalsCadmium and Lead, and the results indicates the very easy transferring of this metals from soil to parsley that was not healthy for human daily consumption and risk and health index (HRI that was above 1 for lead metal shows the hygienic potential risk of this metal in relation to the polluted parsley consumption in human daily alimentary diet.

  17. The Global Streamflow Indices and Metadata Archive (GSIM – Part 2: Quality control, time-series indices and homogeneity assessment

    Directory of Open Access Journals (Sweden)

    L. Gudmundsson

    2018-04-01

    Full Text Available This is Part 2 of a two-paper series presenting the Global Streamflow Indices and Metadata Archive (GSIM, which is a collection of daily streamflow observations at more than 30 000 stations around the world. While Part 1 (Do et al., 2018a describes the data collection process as well as the generation of auxiliary catchment data (e.g. catchment boundary, land cover, mean climate, Part 2 introduces a set of quality controlled time-series indices representing (i the water balance, (ii the seasonal cycle, (iii low flows and (iv floods. To this end we first consider the quality of individual daily records using a combination of quality flags from data providers and automated screening methods. Subsequently, streamflow time-series indices are computed for yearly, seasonal and monthly resolution. The paper provides a generalized assessment of the homogeneity of all generated streamflow time-series indices, which can be used to select time series that are suitable for a specific task. The newly generated global set of streamflow time-series indices is made freely available with an digital object identifier at https://doi.pangaea.de/10.1594/PANGAEA.887470 and is expected to foster global freshwater research, by acting as a ground truth for model validation or as a basis for assessing the role of human impacts on the terrestrial water cycle. It is hoped that a renewed interest in streamflow data at the global scale will foster efforts in the systematic assessment of data quality and provide momentum to overcome administrative barriers that lead to inconsistencies in global collections of relevant hydrological observations.

  18. The Global Streamflow Indices and Metadata Archive (GSIM) - Part 2: Quality control, time-series indices and homogeneity assessment

    Science.gov (United States)

    Gudmundsson, Lukas; Do, Hong Xuan; Leonard, Michael; Westra, Seth

    2018-04-01

    This is Part 2 of a two-paper series presenting the Global Streamflow Indices and Metadata Archive (GSIM), which is a collection of daily streamflow observations at more than 30 000 stations around the world. While Part 1 (Do et al., 2018a) describes the data collection process as well as the generation of auxiliary catchment data (e.g. catchment boundary, land cover, mean climate), Part 2 introduces a set of quality controlled time-series indices representing (i) the water balance, (ii) the seasonal cycle, (iii) low flows and (iv) floods. To this end we first consider the quality of individual daily records using a combination of quality flags from data providers and automated screening methods. Subsequently, streamflow time-series indices are computed for yearly, seasonal and monthly resolution. The paper provides a generalized assessment of the homogeneity of all generated streamflow time-series indices, which can be used to select time series that are suitable for a specific task. The newly generated global set of streamflow time-series indices is made freely available with an digital object identifier at https://doi.pangaea.de/10.1594/PANGAEA.887470" target="_blank">https://doi.pangaea.de/10.1594/PANGAEA.887470 and is expected to foster global freshwater research, by acting as a ground truth for model validation or as a basis for assessing the role of human impacts on the terrestrial water cycle. It is hoped that a renewed interest in streamflow data at the global scale will foster efforts in the systematic assessment of data quality and provide momentum to overcome administrative barriers that lead to inconsistencies in global collections of relevant hydrological observations.

  19. Wide-Area Assessment of Aperiodic Small Signal Rotor Angle Stability in Real-Time

    DEFF Research Database (Denmark)

    Jóhannsson, Hjörtur; Nielsen, Arne Hejde; Østergaard, Jacob

    2013-01-01

    This paper presents the details of a new real-time stability assessment method. The method assesses a particular mechanism of stability: each generator’s capability to generate sufficient steady state electromechanical torque. The lack of sufficient steady state torque causes aperiodic increase...... of multiple operating points is derived in the paper. Finally, results from time-domain simulation of instability scenarios in the Nordic32 test system are presented and results used for testing the assessment method. The results illustrate the method’s capability to efficiently identify the location...... in rotor angle and a loss of synchronism, referred to as aperiodic small signal instability. The paper provides the theoretical background of the method and an analytical assessment criterion. Furthermore, a mathematical mapping of the generators’ operating points that enables informative visualization...

  20. Timeliness “at a glance”: assessing the turnaround time through the six sigma metrics.

    Science.gov (United States)

    Ialongo, Cristiano; Bernardini, Sergio

    2016-01-01

    Almost thirty years of systematic analysis have proven the turnaround time to be a fundamental dimension for the clinical laboratory. Several indicators are to date available to assess and report quality with respect to timeliness, but they sometimes lack the communicative immediacy and accuracy. The six sigma is a paradigm developed within the industrial domain for assessing quality and addressing goal and issues. The sigma level computed through the Z-score method is a simple and straightforward tool which delivers quality by a universal dimensionless scale and allows to handle non-normal data. Herein we report our preliminary experience in using the sigma level to assess the change in urgent (STAT) test turnaround time due to the implementation of total automation. We found that the Z-score method is a valuable and easy to use method for assessing and communicating the quality level of laboratory timeliness, providing a good correspondence with the actual change in efficiency which was retrospectively observed.

  1. Effects of aging time on the mechanical properties of Sn–9Zn–1.5Ag–xBi lead-free solder alloys

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Chih-Yao [Department of Materials Science and Engineering, National Cheng Kung University, 1 Ta-Hsueh Road, Tainan 70101, Taiwan (China); Hon, Min-Hsiung [Department of Materials Science and Engineering, National Cheng Kung University, 1 Ta-Hsueh Road, Tainan 70101, Taiwan (China); Department of Mechanical Engineering, National Kaohsiung University of Applied Sciences, 415 Chien-Kung Road, Kaohsiung 80782, Taiwan (China); Wang, Moo-Chin, E-mail: mcwang@kmu.edu.tw [Department of Fragrance and Cosmetic Science, Kaohsiung Medical University, 100, Shih-Chuan 1st Road, Kaohsiung 80728, Taiwan (China); Chen, Ying-Ru; Chang, Kuo-Ming; Li, Wang-Long [Institute of Nanotechnology and Microsystems Engineering, National Cheng Kung University, No. 1, University Road, Tainan 70101, Taiwan (China)

    2014-01-05

    Highlights: • The microstructure of these solder alloys are composed of Sn-rich phase and Ag{sub 3}Sn. • The grain size of Sn–9Zn–1.5Ag–xBi solder alloys increases with rose aging time. • The maximum yield strength is 112.7 ± 2.2 MPa for Sn–9Zn–1.5Ag–3Bi solder alloys. • TEM observed that Bi appears as oblong shape fine particles. -- Abstract: The effects of aging time on the mechanical properties of the Sn–9Zn–1.5Ag–xBi lead-free solder alloys are investigated using scanning electron microscopy (SEM), X-ray diffraction (XRD), transmission electron microscopy (TEM), selected area electron diffraction (SAED), energy dispersive spectrometry (EDS) and a universal testing machine. The experimental results show that the microstructure of Sn–9Zn–1.5Ag–xBi solder alloys is composed of Sn-rich phase and AgZn{sub 3}. No other intermetallic compounds (IMCs) with Bi content was observed in the solder matrix for Sn–9Zn–1.5Ag solder alloys with various Bi contents before and after aging at 150 °C for different durations. The lattice parameter increases significantly with increasing aging time or Bi addition. The size of Sn-rich grain increased gradually with aging time increased, but decreases with Bi content increases. The maximum yield strength is 112.7 ± 2.2 MPa for Sn–9Zn–1.5Ag–3Bi solder alloy before aging.

  2. Effects of aging time on the mechanical properties of Sn–9Zn–1.5Ag–xBi lead-free solder alloys

    International Nuclear Information System (INIS)

    Liu, Chih-Yao; Hon, Min-Hsiung; Wang, Moo-Chin; Chen, Ying-Ru; Chang, Kuo-Ming; Li, Wang-Long

    2014-01-01

    Highlights: • The microstructure of these solder alloys are composed of Sn-rich phase and Ag 3 Sn. • The grain size of Sn–9Zn–1.5Ag–xBi solder alloys increases with rose aging time. • The maximum yield strength is 112.7 ± 2.2 MPa for Sn–9Zn–1.5Ag–3Bi solder alloys. • TEM observed that Bi appears as oblong shape fine particles. -- Abstract: The effects of aging time on the mechanical properties of the Sn–9Zn–1.5Ag–xBi lead-free solder alloys are investigated using scanning electron microscopy (SEM), X-ray diffraction (XRD), transmission electron microscopy (TEM), selected area electron diffraction (SAED), energy dispersive spectrometry (EDS) and a universal testing machine. The experimental results show that the microstructure of Sn–9Zn–1.5Ag–xBi solder alloys is composed of Sn-rich phase and AgZn 3 . No other intermetallic compounds (IMCs) with Bi content was observed in the solder matrix for Sn–9Zn–1.5Ag solder alloys with various Bi contents before and after aging at 150 °C for different durations. The lattice parameter increases significantly with increasing aging time or Bi addition. The size of Sn-rich grain increased gradually with aging time increased, but decreases with Bi content increases. The maximum yield strength is 112.7 ± 2.2 MPa for Sn–9Zn–1.5Ag–3Bi solder alloy before aging

  3. Heavy metal pollution and ecological risk assessment of the paddy soils near a zinc-lead mining area in Hunan.

    Science.gov (United States)

    Lu, Sijin; Wang, Yeyao; Teng, Yanguo; Yu, Xuan

    2015-10-01

    Soil pollution by Cd, Hg, As, Pb, Cr, Cu, and Zn was characterized in the area of the mining and smelting of metal ores at Guiyang, northeast of Hunan Province. A total of 150 topsoil (0-20 cm) samples were collected in May 2012 with a nominal density of one sample per 4 km(2). High concentrations of heavy metals especially, Cd, Zn, and Pb were found in many of the samples taken from surrounding paddy soil, indicating a certain extent of spreading of heavy metal pollution. Sequential extraction technique and risk assessment code (RAC) were used to study the mobility of chemical forms of heavy metals in the soils and their ecological risk. The results reveal that Cd represents a high ecological risk due to its highest percentage of the exchangeable and carbonate fractions. The metals of Zn and Cu pose a medium risk, and the rest of the metals represent a low environmental risk. The range of the potential ecological risk of soil calculated by risk index (RI) was 123.5~2791.2 and revealed a considerable-high ecological risk in study area especially in the neighboring and surrounding the mining activities area. Additionally, cluster analyses suggested that metals such as Pb, As, Hg, Zn, and Cd could be from the same sources probably related to the acidic drainage and wind transport of dust. Cluster analysis also clearly distinguishes the samples with similar characteristics according to their spatial distribution. The results could be used during the ecological risk screening stage, in conjunction with total concentrations and metal fractionation values to better estimate ecological risk.

  4. The Timed 180° Turn Test for Assessing People with Hemiplegia from Chronic Stroke

    Directory of Open Access Journals (Sweden)

    Regan L. Robinson

    2018-01-01

    Full Text Available Background. Turning is ubiquitous in activities of daily living. For people with hemiplegia, persistent impairments in strength, balance, and coordination will affect their ability to turn safely. Consequently, turning retraining should be addressed in rehabilitation programs. To measure turning for these individuals, a reliable clinical tool is required. Objective. To investigate (i the intrarater, interrater, and test-retest reliability of the timed 180° turn test; (ii the correlation of the timed 180° turn test with other measures of stroke-specific impairments; and (iii the cut-off time that best discriminates individuals with hemiplegia from chronic stroke and healthy older adults. Methods. 33 individuals with hemiplegia due to chronic stroke and 32 healthy elderly individuals participated in this cross-sectional study. The timed 180° turn test was administered along with other measures of stroke-specific impairment. Results. The timed 180° turn test demonstrated excellent intrarater, interrater, and test-retest reliability in individuals with hemiplegia from chronic stroke. The timed 180° turn test (times significantly correlated with the Fugl-Meyer Assessment of the Lower Extremities (FMA-LE, affected ankle plantar flexion strength, the 5-Times-Sit-To-Stand test, the Berg Balance Scale (BBS, and the Timed Up and Go (TUG test. Conclusion. The timed 180° turn test is a reliable clinical tool to assess the turning ability of subjects with hemiplegia from chronic stroke.

  5. ASSESSING THE ROLE OF SPIN NOISE IN THE PRECISION TIMING OF MILLISECOND PULSARS

    International Nuclear Information System (INIS)

    Shannon, Ryan M.; Cordes, James M.

    2010-01-01

    We investigate rotational spin noise (referred to as timing noise) in non-accreting pulsars: millisecond pulsars, canonical pulsars, and magnetars. Particular attention is placed on quantifying the strength and non-stationarity of timing noise in millisecond pulsars because the long-term stability of these objects is required to detect nanohertz gravitational radiation. We show that a single scaling law is sufficient to characterize timing noise in millisecond and canonical pulsars while the same scaling law underestimates the levels of timing noise in magnetars. The scaling law, along with a detailed study of the millisecond pulsar B1937+21, leads us to conclude that timing noise is latent in most millisecond pulsars and will be measurable in many objects when better arrival time estimates are obtained over long data spans. The sensitivity of a pulsar timing array to gravitational radiation is strongly affected by any timing noise. We conclude that detection of proposed gravitational wave backgrounds will require the analysis of more objects than previously suggested over data spans that depend on the spectra of both the gravitational wave background and of the timing noise. It is imperative to find additional millisecond pulsars in current and future surveys in order to reduce the effects of timing noise.

  6. Wetland Plant Guide for Assessing Habitat Impacts of Real-Time Salinity Management

    OpenAIRE

    Quinn, Nigel W.T.; Feldmann, Sara A.

    2004-01-01

    This wetland plant guide was developed to aid moist soil plant identification and to assist in the mapping of waterfowl and shorebird habitat in the Grassland Water District and surrounding wetland areas. The motivation for this habitat mapping project was a concern that real-time salinity management of wetland drainage might have long-term consequences for wildfowl habitat health -- changes in wetland drawdown schedules might, over the long term, lead to increased soil salinity and othe...

  7. Uranium-lead systematics

    International Nuclear Information System (INIS)

    Wickman, F.E.

    1983-01-01

    The method of Levchenkov and Shukolyukov for calculating age and time disturbance of minerals without correction for original lead is generalized to include the cases when (1) original lead and radiogenic lead leach differently, and (2) the crystals studied consist of a core and a mantle. It is also shown that a straight line obtained from the solution of the equations is the locus of the isotopic composition of original lead. (Auth.)

  8. Safety Culture Monitoring: How to Assess Safety Culture in Real Time?

    International Nuclear Information System (INIS)

    Zronek, B.; Maryska, J.; Treslova, L.

    2016-01-01

    Do you know what is current level of safety culture in your company? Are you able to follow trend changes? Do you know what your recent issues are? Since safety culture is understood as vital part of nuclear industry daily life, it is crucial to know what the current level is. It is common to perform safety culture survey or ad hoc assessment. This contribution shares Temelin NPP, CEZ approach how to assess safety culture level permanently. Using behavioral related outputs of gap solving system, observation program, dedicated surveys, regulatory assessment, etc., allows creating real time safety culture monitoring without the need to perform any other activities. (author)

  9. Suitability of voltage stability study methods for real-time assessment

    DEFF Research Database (Denmark)

    Perez, Angel; Jóhannsson, Hjörtur; Vancraeyveld, Pieter

    2013-01-01

    This paper analyzes the suitability of existing methods for long-term voltage stability assessment for real-time operation. An overview of the relevant methods is followed with a comparison that takes into account the accuracy, computational efficiency and characteristics when used for security...... assessment. The results enable an evaluation of the run time of each method with respect to the number of inputs. Furthermore, the results assist in identifying which of the methods is most suitable for realtime operation in future power system with production based on fluctuating energy sources....

  10. Light water reactor sequence timing: its significance to probabilistic safety assessment modeling

    International Nuclear Information System (INIS)

    Bley, D.C.; Buttemer, D.R.; Stetkar, J.W.

    1988-01-01

    This paper examines event sequence timing in light water reactor plants from the viewpoint of probabilistic safety assessment (PSA). The analytical basis for the ideas presented here come primarily from the authors' work in support of more than 20 PSA studies over the past several years. Timing effects are important for establishing success criteria for support and safety system response and for identifying the time available for operator recovery actions. The principal results of this paper are as follows: 1. Analysis of event sequence timing is necessary for meaningful probabilistic safety assessment - both the success criteria for systems performance and the probability of recovery are tightly linked to sequence timing. 2. Simple engineering analyses based on first principles are often sufficient to provide adequate resolution of the time available for recovery of PSA scenarios. Only those parameters that influence sequence timing and its variability and uncertainty need be examined. 3. Time available for recovery is the basic criterion for evaluation of human performance, whether time is an explicit parameter of the operator actions analysis or not. (author)

  11. Estudo do efeito de programas de melhoria contínua em variáveis do chão de fábrica na relação entre tamanho de lote de produção e lead time: lead time relationship Study of the effect of continuous improvement programs on lot size

    Directory of Open Access Journals (Sweden)

    Moacir Godinho Filho

    2010-01-01

    Full Text Available No atual ambiente competitivo, a tomada de decisão tem se tornado uma tarefa cada vez mais complicada, envolvendo inúmeras variáveis, e suas relações, nem sempre claramente entendidas. Uma dessas relações, foco deste artigo, é a relação entre tamanho de lote de produção e lead time médio. Essa relação é amplamente conhecida na literatura específica sobre teoria de filas, porém o mesmo não acontece na prática em gestão de operações. Este artigo trata deste assunto, objetivando apresentar e comparar o efeito de seis programas de melhoria contínua em variáveis do chão de fábrica (variabilidade da chegada das ordens, variabilidade do processo, taxa de defeito, tempo até a falha, tempo de reparo e tempo de set up na relação tamanho de lote × lead time em um ambiente de máquina única que fabrica múltiplos produtos. Isto é feito por meio de uma combinação das abordagens System Dynamics (Forrester, 1962 e Factory Physics (Hopp; Spearman, 2008. Dois conjuntos de experimentos são realizados: i Uma melhoria de grandes proporções (50% em cada uma das variáveis separadamente, como aquela que seria obtida por um grande investimento; ii Uma pequena melhoria em todas as variáveis simultaneamente. Os resultados mostraram: (a o efeito positivo de programas de melhoria contínua em variáveis do chão de fábrica no lead time; (b a importância de se conhecer a curva tamanho de lote × lead time e o papel da redução de set up antes de se iniciarem programas de redução de tamanhos de lote; (c que investir em pequenas melhorias em muitas variáveis de forma simultânea é uma política melhor, com relação ao lead time, do que realizar uma grande melhoria em somente uma variável; (d algumas contribuições para um melhor entendimento de modernos paradigmas de gestão da produção, tais como Lean Manufaturing e Quick Response Manufacturing.Many modern manufacturing management approaches present relationships between

  12. Context-sensitive ecological momentary assessments; integrating real-time exposure measurements, data-analytics and health assessment using a smartphone application.

    Science.gov (United States)

    van Wel, Luuk; Huss, Anke; Bachmann, Philipp; Zahner, Marco; Kromhout, Hans; Fröhlich, Jürg; Vermeulen, Roel

    2017-06-01

    Modern sensor technology makes it possible to collect vast amounts of environmental, behavioural and health data. These data are often linked to contextual information on for example exposure sources which is separately collected with considerable lag time, leading to complications in assessing transient and/or highly spatially variable environmental exposures. Context-Sensitive Ecological Momentary Assessments 1 (CS-EMAs) could be used to address this. We present a case study using radiofrequency-electromagnetic fields (RF-EMF) exposure as an example for implementing CS-EMA in environmental research. Participants were asked to install a custom application on their own smartphone and to wear an RF-EMF exposimeter for 48h. Questionnaires were triggered by the application based on a continuous data stream from the exposimeter. Triggers were divided into four categories: relative and absolute exposure levels, phone calls, and control condition. After the two days of use participants filled in an evaluation questionnaire. 74% of all CS-EMAs were completed, with an average time of 31s to complete a questionnaire once it was opened. Participants reported minimal influence on daily activities. There were no significant differences found between well-being and type of RF-EMF exposure. We show that a CS-EMA based method could be used in environmental research. Using several examples involving environmental stressors, we discuss both current and future applications of this methodology in studying potential health effects of environmental factors. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Leading change.

    Science.gov (United States)

    2017-02-27

    In response to feedback from nursing, midwifery and other care staff who wanted to understand better how the Leading Change, Adding Value framework applies to them, NHS England has updated its webpage to include practice examples.

  14. Delay times between harvesting or collection of food products and consumption for use in radiological assessments

    International Nuclear Information System (INIS)

    Jones, A L; Sherwood, J C

    2009-01-01

    From a radiological protection point of view, the inclusion of delay times when carrying out assessments of dose from consumption of foods should be considered. A review of delay times has been carried out to update a report published in 1983, to take account of changes and modernisations in industrial food processes, together with changes in diet and popularity of different foods in the United Kingdom. The new review considered more foods and data for existing foods have been reconsidered to check whether manufacturing processes or procedures have changed the shelf-life of any products. For some foods there have been changes made to the recommended delay times because of changes in manufacture or handling of the fresh foodstuff. A discussion is also included on the appropriate use of delay times in dose assessments.

  15. Investigation of the Adaptability of Transient Stability Assessment Methods to Real-Time Operation

    OpenAIRE

    Weckesser, Johannes Tilman Gabriel; Jóhannsson, Hjörtur; Sommer, Stefan; Østergaard, Jacob

    2012-01-01

    In this paper, an investigation of the adaptability of available transient stability assessment methods to real-time operation and their real-time performance is carried out. Two approaches based on Lyapunov’s method and the equal area criterion are analyzed. The results allow to determine the runtime of each method with respect to the number of inputs. Furthermore, it allows to identify, which method is preferable in case of changes in the power system such as the integration of distributed ...

  16. Does Work Time Flexibility Work? An Empirical Assessment of the Efficiency Effects for German Firms

    OpenAIRE

    Wolf, Elke; Beblo, Miriam

    2004-01-01

    In this paper we assess the impact of flexible work time schedules on firm efficiency using representative establishment data for Germany. Following the approach by Battese and Coelli (1995), we estimate a stochastic production frontier and the determinants of technical efficiency simultaneously. The innovation of our study is that we draw on technical efficiency instead of productivity to appraise the success of flexible working hours. The results indicate that while the use of work time sch...

  17. Frit Development Efforts for Sludge Batch 4 (SB4): Operating Window Assessments of Scenarios Leading Up to the Selected Preparation Plan for SB4

    International Nuclear Information System (INIS)

    Peeler, D

    2006-01-01

    The objective of this report is to document technical information that has been provided to Defense Waste Processing Facility (DWPF) and Closure Business Unit (CBU) personnel as part of the frit development support for Sludge Batch 4 (SB4). The information presented in this report includes projected operating windows (expressed in terms of waste loading) for various sludge blending and/or washing options coupled with candidate frits of interest. Although the Nominal Stage assessment serves as the primary tool for these evaluations, select systems were also evaluated using a Variation Stage assessment in which compositional variations were introduced. In addition, assessments of the impacts of nepheline formation potential and the SO 4 - solubility limit on the projected operating windows are also provided. Although this information was used as part of the technical basis leading to CBU's development of the preferred SB4 preparation plan, none of the options presented in this report was selected as the preferred plan. Therefore, the information is presented without significant interpretation of the resulting operating windows, but the projected windows are provided so additional insight can be explored if desired. Detailed assessments of the projected operating windows (using both Nominal and Variation Stage assessments) of the preferred sludge preparation plan with candidate frits are to be documented elsewhere. The information provided in this report is focused solely on model-based projections of the operating windows for various SB4 blending strategies of interest. Although nepheline formation potential is monitored via model predictions as a part of this assessment, experimental work investigating the impact of nepheline on glass quality is also being addressed in a parallel study. The results of this paper study and the experimental assessments of melt rate, SO 4 solubility, and/or nepheline formation potential are all critical components of the inputs into

  18. Assessment of time management skills: psychometric properties of the Swedish version.

    Science.gov (United States)

    Janeslätt, Gunnel Kristina; Holmqvist, Kajsa Lidström; White, Suzanne; Holmefur, Marie

    2018-05-01

    Persons with impaired time management skills are often in need of occupational therapy. Valid and reliable instruments to assess time management and organizational skills are needed for the evaluation of intervention. The purpose of this study was to evaluate the psychometric properties of a Swedish version of the Assessment of Time Management Skills (ATMS-S) for persons with and without impaired time management skills. A total of 238 persons participated in the study, of whom 94 had self-reported impaired time management skills due to mental disorders such as schizophrenic spectrum or neurodevelopmental disorders such as attention deficit/hyperactivity disorder (ADHD), autism spectrum disorder (ASD) and mild intellectual disabilities, and 144 persons had no reported impaired time management skills. Rasch analysis was used to analyze data. Three subscales were detected: the time management subscale with 11 items, the organization & planning subscale with 11 items, and the subscale of regulation of emotions with 5 items, with excellent to acceptable psychometric properties. The conclusions were that: ATMS-S is a valid instrument for self-rating of time management, organization & planning and for the regulation of emotions. ATMS-S can be useful for persons with mental disorders including mild neurodevelopmental disorders.

  19. Transferability and robustness of real-time freeway crash risk assessment.

    Science.gov (United States)

    Shew, Cameron; Pande, Anurag; Nuworsoo, Cornelius

    2013-09-01

    This study examines the data from single loop detectors on northbound (NB) US-101 in San Jose, California to estimate real-time crash risk assessment models. The classification tree and neural network based crash risk assessment models developed with data from NB US-101 are applied to data from the same freeway, as well as to the data from nearby segments of the SB US-101, NB I-880, and SB I-880 corridors. The performance of crash risk assessment models on these nearby segments is the focus of this research. The model applications show that it is in fact possible to use the same model for multiple freeways, as the underlying relationships between traffic data and crash risk remain similar. The framework provided here may be helpful to authorities for freeway segments with newly installed traffic surveillance apparatuses, since the real-time crash risk assessment models from nearby freeways with existing infrastructure would be able to provide a reasonable estimate of crash risk. The robustness of the model output is also assessed by location, time of day, and day of week. The analysis shows that on some locations the models may require further learning due to higher than expected false positive (e.g., the I-680/I-280 interchange on US-101 NB) or false negative rates. The approach for post-processing the results from the model provides ideas to refine the model prior to or during the implementation. Copyright © 2013 National Safety Council and Elsevier Ltd. All rights reserved.

  20. Dynamic life-time assessing method for the N1C700 turbine's rotor

    International Nuclear Information System (INIS)

    Popescu-Vifor, B.

    1993-01-01

    The N1C700 turbine's rotor subject to different sorts of stress variations was investigated through dynamic life-time assessing method. To obtain the temperature fields at different steam parameters inside the turbine components, a computer code named DENOPAR was developed

  1. Assessment of Smolt Condition for Travel Time Analysis, 1993-1994 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Schrock, Robin M; Beeman, John W; VanderKooi, Scott P [US Geological Survey, Western Fisheries Research Center, Columbia River Research Laboratory, Cook, WA

    1999-02-01

    The assessment of smolt condition for travel time analysis (ASCTTA) project provided information on the level of smoltification in Columbia River hatchery and wild salmonid stocks to the Fish Passage Center (FPC), for the primary purpose of in-river management of flows.

  2. A Real-Time Plagiarism Detection Tool for Computer-Based Assessments

    Science.gov (United States)

    Jeske, Heimo J.; Lall, Manoj; Kogeda, Okuthe P.

    2018-01-01

    Aim/Purpose: The aim of this article is to develop a tool to detect plagiarism in real time amongst students being evaluated for learning in a computer-based assessment setting. Background: Cheating or copying all or part of source code of a program is a serious concern to academic institutions. Many academic institutions apply a combination of…

  3. Probabilistic tsunami hazard assessment considering time-lag of seismic event on Nankai trough

    International Nuclear Information System (INIS)

    Sugino, Hideharu; Sakagami, Masaharu; Ebisawa, Katsumi; Korenaga, Mariko

    2011-01-01

    In the area in front of Nankai trough, tsunami wave height may increase if tsunamis attacking from some wave sources overlap because of time-lag of seismic event on Nankai trough. To evaluation tsunami risk of the important facilities located in front of Nankai trough, we proposed the probabilistic tsunami hazard assessment considering uncertainty on time-lag of seismic event on Nankai trough and we evaluated the influence that the time-lag gave to tsunami hazard at the some representative points. (author)

  4. [Unification of methods for determining the trace quantities of lead, zinc, sodium and potassium ions in the assessment of drinking water adn transfusion fluid quality].

    Science.gov (United States)

    Popkov, V A; Golovina, N V; Evgrafov, A A

    2001-01-01

    The results of long-term studies made by the Department of General Chemistry, I. M. Sechenov Moscow Medical Academy, that deals with unification of methods for determining some ions of metals (lead, zinc, sodium, and potassium) in the assessment of the quality of drinking water and transfusion fluids are summarized. A procedure was developed to determine the trace impurities of zinc, lead, and silver by atomic absorption spectrometry (AAS) by using sorption concentration. C-80-2-aminothiazole, a new sorbent synthesized at the Research Institute of Polymers, was used to detect these ions in the drinking water. With regards to the chosen optimal conditions, drinking water samples were analyzed via their direct spraying in the air-acetylene flame. The prior sorption concentration determined drinking water zinc and lead ions in the concentrations equal to or less than their permissible dose concentrations. The studies indicated that the used methods to determine the trace quantities of metals in the drinking water and aqueous solutions show a high sensitivity, rapidity, simplicity of sample preparation.

  5. Cadmium, lead, and chromium in large game: a local-scale exposure assessment for hunters consuming meat and liver of wild boar.

    Science.gov (United States)

    Danieli, P P; Serrani, F; Primi, R; Ponzetta, M P; Ronchi, B; Amici, A

    2012-11-01

    Heavy metals are ubiquitous in soil, water, and air. Their entrance into the food chain is an important environmental issue that entails risks to humans. Several reports indicate that game meat can be an important source of heavy metals, particularly because of the increasing consumption of game meat, mainly by hunters. We performed an exposure assessment of hunters and members of their households, both adults and children, who consumed wild boar (WB) meat and offal. We estimated the amount of cadmium, lead, and chromium in the tissues of WB hunted in six areas within Viterbo Province (Italy) and gathered data on WB meat and offal consumption by conducting specific diet surveys in the same areas. The exposure to cadmium, lead, and chromium was simulated with specifically developed Monte Carlo simulation models. Cadmium and lead levels in WB liver and meat harvested in Viterbo Province (Italy) were similar to or lower than the values reported in other studies. However, some samples contained these metals at levels greater then the EU limits set for domestic animals. The chromium content of meat or liver cannot be evaluated against any regulatory limit, but our results suggest that the amounts of this metal found in WB products may reflect a moderate environmental load. Our survey of the hunter population confirmed that their consumption of WB meat and liver was greater than that of the general Italian population. This level of consumption was comparable with other European studies. Consumption of WB products contributes significantly to cadmium and lead exposure of both adults and children. More specifically, consumption of the WB liver contributed significantly to total cadmium and lead exposure of members of the households of WB hunters. As a general rule, liver consumption should be kept to a minimum, especially for children living in these hunter households. The exposure to chromium estimated for this population of hunters may be considered to be safe. However

  6. Cochrane Rapid Reviews Methods Group to play a leading role in guiding the production of informed high-quality, timely research evidence syntheses.

    Science.gov (United States)

    Garritty, Chantelle; Stevens, Adrienne; Gartlehner, Gerald; King, Valerie; Kamel, Chris

    2016-10-28

    Policymakers and healthcare stakeholders are increasingly seeking evidence to inform the policymaking process, and often use existing or commissioned systematic reviews to inform decisions. However, the methodologies that make systematic reviews authoritative take time, typically 1 to 2 years to complete. Outside the traditional SR timeline, "rapid reviews" have emerged as an efficient tool to get evidence to decision-makers more quickly. However, the use of rapid reviews does present challenges. To date, there has been limited published empirical information about this approach to compiling evidence. Thus, it remains a poorly understood and ill-defined set of diverse methodologies with various labels. In recent years, the need to further explore rapid review methods, characteristics, and their use has been recognized by a growing network of healthcare researchers, policymakers, and organizations, several with ties to Cochrane, which is recognized as representing an international gold standard for high-quality, systematic reviews. In this commentary, we introduce the newly established Cochrane Rapid Reviews Methods Group developed to play a leading role in guiding the production of rapid reviews given they are increasingly employed as a research synthesis tool to support timely evidence-informed decision-making. We discuss how the group was formed and outline the group's structure and remit. We also discuss the need to establish a more robust evidence base for rapid reviews in the published literature, and the importance of promoting registration of rapid review protocols in an effort to promote efficiency and transparency in research. As with standard systematic reviews, the core principles of evidence-based synthesis should apply to rapid reviews in order to minimize bias to the extent possible. The Cochrane Rapid Reviews Methods Group will serve to establish a network of rapid review stakeholders and provide a forum for discussion and training. By facilitating

  7. Ecotoxicology: Lead

    Science.gov (United States)

    Scheuhammer, A.M.; Beyer, W.N.; Schmitt, C.J.; Jorgensen, Sven Erik; Fath, Brian D.

    2008-01-01

    Lead (Pb) is a naturally occurring metallic element; trace concentrations are found in all environmental media and in all living things. However, certain human activities, especially base metal mining and smelting; combustion of leaded gasoline; the use of Pb in hunting, target shooting, and recreational angling; the use of Pb-based paints; and the uncontrolled disposal of Pb-containing products such as old vehicle batteries and electronic devices have resulted in increased environmental levels of Pb, and have created risks for Pb exposure and toxicity in invertebrates, fish, and wildlife in some ecosystems.

  8. The euglobulin clot lysis time to assess the impact of nanoparticles on fibrinolysis

    Energy Technology Data Exchange (ETDEWEB)

    Minet, Valentine, E-mail: valentine.minet@unamur.be; Alpan, Lutfiye; Mullier, François [University of Namur – UNamur, Department of Pharmacy, Namur Thrombosis and Hemostasis Center (NTHC), Namur Nanosafety Center (NNC), NAmur Research Institute for Life Sciences NARILIS (Belgium); Toussaint, Olivier [Laboratory of Cellular Biochemistry and Biology (URBC) (Belgium); Lucas, Stéphane [University of Namur (UNamur), Research Centre for the Physics of Matter and Radiation (PMR-LARN), Namur Nanosafety Center NNC, NAmur Research Institute for Life Sciences NARILIS (Belgium); Dogné, Jean-Michel; Laloy, Julie, E-mail: julie.laloy@unamur.be [University of Namur – UNamur, Department of Pharmacy, Namur Thrombosis and Hemostasis Center (NTHC), Namur Nanosafety Center (NNC), NAmur Research Institute for Life Sciences NARILIS (Belgium)

    2015-07-15

    Nanoparticles (NPs) are developed for many applications in various fields, including nanomedicine. The NPs used in nanomedicine may disturb homeostasis in blood. Secondary hemostasis (blood coagulation) and fibrinolysis are complex physiological processes regulated by activators and inhibitors. An imbalance of this system can either lead to the development of hemorrhages or thrombosis. No data are currently available on the impact of NPs on fibrinolysis. The objectives of this study are (1) to select a screening test to study ex vivo the impact of NPs on fibrinolysis and (2) to test NPs with different physicochemical properties. Euglobulin clot lysis time test was selected to screen the impact of some NPs on fibrinolysis using normal pooled plasma. A dose-dependent decrease in the lysis time was observed with silicon dioxide and silver NPs without disturbing the fibrin network. Carbon black, silicon carbide, and copper oxide did not affect the lysis time at the tested concentrations.

  9. Agreement between activPAL and ActiGraph for assessing children's sedentary time

    Directory of Open Access Journals (Sweden)

    Ridgers Nicola D

    2012-02-01

    Full Text Available Abstract Background Accelerometers have been used to determine the amount of time that children spend sedentary. However, as time spent sitting may be detrimental to health, research is needed to examine whether accelerometer sedentary cut-points reflect the amount of time children spend sitting. The aim of this study was to: a examine agreement between ActiGraph (AG cut-points for sedentary time and objectively-assessed periods of free-living sitting and sitting plus standing time using the activPAL (aP; and b identify cut-points to determine time spent sitting and sitting plus standing. Methods Forty-eight children (54% boys aged 8-12 years wore a waist-mounted AG and thigh-mounted aP for two consecutive school days (9-3:30 pm. AG data were analyzed using 17 cut-points between 50-850 counts·min-1 in 50 counts·min-1 increments to determine sedentary time during class-time, break time and school hours. Sitting and sitting plus standing time were obtained from the aP for these periods. Limits of agreement were computed to evaluate bias between AG50 to AG850 sedentary time and sitting and sitting plus standing time. Receiver Operator Characteristic (ROC analyses identified AG cut-points that maximized sensitivity and specificity for sitting and sitting plus standing time. Results The smallest mean bias between aP sitting time and AG sedentary time was AG150 for class time (3.8 minutes, AG50 for break time (-0.8 minutes, and AG100 for school hours (-5.2 minutes. For sitting plus standing time, the smallest bias was observed for AG850. ROC analyses revealed an optimal cut-point of 96 counts·min-1 (AUC = 0.75 for sitting time, which had acceptable sensitivity (71.7% and specificity (67.8%. No optimal cut-point was obtained for sitting plus standing (AUC = 0.51. Conclusions Estimates of free-living sitting time in children during school hours can be obtained using an AG cut-point of 100 counts·min-1. Higher sedentary cut-points may capture both

  10. Uso de los datos de plumbemia para evaluar y prevenir el envenenamiento infantil por plomo en Latinoamérica Use of blood lead data in epidemiological studies to assess and prevent childhood lead poisoning in Latin America

    Directory of Open Access Journals (Sweden)

    Isabelle Romieu

    2003-01-01

    widespread and serious threat to the health of children in Latin America. Health officials should monitor sources of exposure and health outcomes to design, implement, and evaluate prevention and control activities. To evaluate the magnitude of lead as a public health problem, three key elements must be defined: 1 the potential sources of exposure, 2 the indicators to evaluate health effects and environmental exposure, and 3 the sampling methods for the population at risk. Several strategies can be used to select the study population depending on the study objectives, the time limitations, and the available resources. If the objective is to evaluate the magnitude and sources of the problem, the following sampling methods can be used: 1 population-based random sampling; 2 facility-based random sampling within hospitals, daycare centers, or schools; 3 target sampling of high risk groups; 4 convenience sampling of volunteers; and 5 case reporting (which can lead to the identification of populations at risk and sources of exposures. For all sampling methods, information gathering should include the use of a questionnaire to collect general information on the participants and on potential local sources of exposure, as well as the collection of biological samples. In interpreting data, one should consider the type of sampling used and the non-response rates, as well as factors that might influence blood lead measurements, such as age and seasonal variability. Blood lead measurements should be integrated in an overall strategy to prevent lead toxicity in children.

  11. Leading men

    DEFF Research Database (Denmark)

    Bekker-Nielsen, Tønnes

    2016-01-01

    Through a systematic comparison of c. 50 careers leading to the koinarchate or high priesthood of Asia, Bithynia, Galatia, Lycia, Macedonia and coastal Pontus, as described in funeral or honorary inscriptions of individual koinarchs, it is possible to identify common denominators but also disting...

  12. Strategy for the lowering and the assessment of exposure to nanoparticles at workspace - Case of study concerning the potential emission of nanoparticles of Lead in an epitaxy laboratory

    International Nuclear Information System (INIS)

    Artous, Sébastien; Zimmermann, Eric; Locatelli, Dominique; Motellier, Sylvie; Derrough, Samir; Douissard, Paul-Antoine

    2015-01-01

    The implementation in many products of manufactured nanoparticles is growing fast and raises new questions. For this purpose, the CEA - NanoSafety Platform is developing various research topics for health and safety, environment and nanoparticles exposure in professional activities. The containment optimisation for the exposition lowering, then the exposure assessment to nanoparticles is a strategy for safety improvement at workplace and workspace. The lowering step consists in an optimisation of dynamic and static containment at workplace and/or workspace. Generally, the exposure risk due to the presence of nanoparticles substances does not allow modifying the parameters of containment at workplace and/or workspace. Therefore, gaseous or nanoparticulate tracers are used to evaluate performances of containment. Using a tracer allows to modify safely the parameters of the dynamic containment (ventilation, flow, speed) and to study several configurations of static containment. Moreover, a tracer allows simulating accidental or incidental situation. As a result, a safety procedure can be written more easily in order to manage this type of situation. The step of measurement and characterization of aerosols can therefore be used to assess the exposition at workplace and workspace. The case of study, aim of this paper, concerns the potential emission of Lead nanoparticles at the exhaust of a furnace in an epitaxy laboratory. The use of Helium tracer to evaluate the performance of containment is firstly studied. Secondly, the exposure assessment is characterised in accordance with the French guide “recommendations for characterizing potential emissions and exposure to aerosols released from nanomaterials in workplace operations”. Thirdly the aerosols are sampled, on several places, using collection membranes to try to detect traces of Lead in air. (paper)

  13. Strategy for the lowering and the assessment of exposure to nanoparticles at workspace - Case of study concerning the potential emission of nanoparticles of Lead in an epitaxy laboratory

    Science.gov (United States)

    Artous, Sébastien; Zimmermann, Eric; Douissard, Paul-Antoine; Locatelli, Dominique; Motellier, Sylvie; Derrough, Samir

    2015-05-01

    The implementation in many products of manufactured nanoparticles is growing fast and raises new questions. For this purpose, the CEA - NanoSafety Platform is developing various research topics for health and safety, environment and nanoparticles exposure in professional activities. The containment optimisation for the exposition lowering, then the exposure assessment to nanoparticles is a strategy for safety improvement at workplace and workspace. The lowering step consists in an optimisation of dynamic and static containment at workplace and/or workspace. Generally, the exposure risk due to the presence of nanoparticles substances does not allow modifying the parameters of containment at workplace and/or workspace. Therefore, gaseous or nanoparticulate tracers are used to evaluate performances of containment. Using a tracer allows to modify safely the parameters of the dynamic containment (ventilation, flow, speed) and to study several configurations of static containment. Moreover, a tracer allows simulating accidental or incidental situation. As a result, a safety procedure can be written more easily in order to manage this type of situation. The step of measurement and characterization of aerosols can therefore be used to assess the exposition at workplace and workspace. The case of study, aim of this paper, concerns the potential emission of Lead nanoparticles at the exhaust of a furnace in an epitaxy laboratory. The use of Helium tracer to evaluate the performance of containment is firstly studied. Secondly, the exposure assessment is characterised in accordance with the French guide “recommendations for characterizing potential emissions and exposure to aerosols released from nanomaterials in workplace operations”. Thirdly the aerosols are sampled, on several places, using collection membranes to try to detect traces of Lead in air.

  14. Ground and Helicopter Emergency Medical Services Time Tradeoffs Assessed with Geographic Information.

    Science.gov (United States)

    Widener, Michael J; Ginsberg, Zac; Schleith, Daniel; Floccare, Douglas J; Hirshon, Jon Mark; Galvagno, Samuel

    2015-07-01

    We describe how geographic information systems (GIS) can be used to assess and compare estimated transport time for helicopter and ground emergency medical services. Recent research shows that while the odds of a trauma patient's survival increase with helicopter emergency medical services (HEMS), they may not increase to the extent necessary to make HEMS cost effective. This study offers an analytic tool to objectively quantify the patient travel time advantage that HEMS offers compared to ground emergency medical services (GEMS). Using helicopter dispatch data from the Maryland State Police from 2000-2011, we computed transport time estimates for HEMS and GEMS, compare these results to a reference transport time of 60 min, and use geospatial interpolation to extrapolate the total response times for each mode across the study region. Mapping the region's trauma incidents and modeling response times, our findings indicate the GIS framework for calculating transportation time tradeoffs is useful in identifying which areas can be better served by HEMS or GEMS. The use of GIS and the analytical methodology described in this study present a method to compare transportation by air and ground in the prehospital setting that accounts for how mode, distance, and road infrastructure impact total transport time. Whether used to generate regional maps in advance or applied real-time, the presented framework provides a tool to identify earlier incident locations that favor HEMS over GEMS transport modes.

  15. Assessing and minimizing contamination in time of flight based validation data

    Science.gov (United States)

    Lennox, Kristin P.; Rosenfield, Paul; Blair, Brenton; Kaplan, Alan; Ruz, Jaime; Glenn, Andrew; Wurtz, Ronald

    2017-10-01

    Time of flight experiments are the gold standard method for generating labeled training and testing data for the neutron/gamma pulse shape discrimination problem. As the popularity of supervised classification methods increases in this field, there will also be increasing reliance on time of flight data for algorithm development and evaluation. However, time of flight experiments are subject to various sources of contamination that lead to neutron and gamma pulses being mislabeled. Such labeling errors have a detrimental effect on classification algorithm training and testing, and should therefore be minimized. This paper presents a method for identifying minimally contaminated data sets from time of flight experiments and estimating the residual contamination rate. This method leverages statistical models describing neutron and gamma travel time distributions and is easily implemented using existing statistical software. The method produces a set of optimal intervals that balance the trade-off between interval size and nuisance particle contamination, and its use is demonstrated on a time of flight data set for Cf-252. The particular properties of the optimal intervals for the demonstration data are explored in detail.

  16. Improved Thévenin equivalent methods for real-time voltage stability assessment

    DEFF Research Database (Denmark)

    Perez, Angel; Jóhannsson, Hjörtur; Østergaard, Jacob

    2016-01-01

    An improved Thévenin equivalent method for real-time voltage stability assessment that uses wide-area information from synchrophasors is proposed. The improvements are a better modeling of the limited synchronous generators, and a processing that anticipates the effect of field current limiters......, before the latter are activated. Several study cases using detailed dynamic simulations of the Nordic test system have been used to assess the performance of the proposed improvements. Their effectiveness is analyzed and, based on the results, their possible application in combination...

  17. Evaluation of HVDC interconnection models for considering its impact in real-time voltage stability assessment

    DEFF Research Database (Denmark)

    Perez, Angel; Jóhannsson, Hjörtur; Lund, P.

    2015-01-01

    An approach to evaluate the HVDC interconnectionsmodels to be used in real-time voltage stability assessment is proposed.The existing models for the HVDC interconnections, thatare based on voltage source converter, were studied selecting theones that are suitable for its application in Thevenin...... equivalent ´methods for voltage stability assessment. The proposed methodis to evaluate the validity of the models by using synthetizedPMU measurements from simulations and from PMUs connectedto the danish system. Wide-area measurements are used toestimate the HVDC model parameters which are needed...

  18. Cost, Time, and Risk Assessment of Different Wave Energy Converter Technology Development Trajectories: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Weber, Jochem W [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Laird, Daniel [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Costello, Ronan [Wave Venture; Roberts, Jesse [Sandia National Laboratories; Bull, Diana [Sandia National Laboratories; Babarit, Aurelien [Ecole Centrale de Nantes; Nielsen, Kim [Ramboll; Ferreira, Claudio Bittencourt [DNV-GL; Kennedy, Ben [Wave Venture

    2017-09-14

    This paper presents a comparative assessment of three fundamentally different wave energy converter technology development trajectories. The three technology development trajectories are expressed and visualised as a function of technology readiness levels and technology performance levels. The assessment shows that development trajectories that initially prioritize technology readiness over technology performance are likely to require twice the development time, consume a threefold of the development cost, and are prone to a risk of technical or commercial failure of one order of magnitude higher than those development trajectories that initially prioritize technology performance over technology readiness.

  19. Self-Motion Perception: Assessment by Real-Time Computer Generated Animations

    Science.gov (United States)

    Parker, Donald E.

    1999-01-01

    Our overall goal is to develop materials and procedures for assessing vestibular contributions to spatial cognition. The specific objective of the research described in this paper is to evaluate computer-generated animations as potential tools for studying self-orientation and self-motion perception. Specific questions addressed in this study included the following. First, does a non- verbal perceptual reporting procedure using real-time animations improve assessment of spatial orientation? Are reports reliable? Second, do reports confirm expectations based on stimuli to vestibular apparatus? Third, can reliable reports be obtained when self-motion description vocabulary training is omitted?

  20. A study on assessment methodology of surveillance test interval and Allowed Outage Time

    International Nuclear Information System (INIS)

    Che, Moo Seong; Cheong, Chang Hyeon; Ryu, Yeong Woo; Cho, Jae Seon; Heo, Chang Wook; Kim, Do Hyeong; Kim, Joo Yeol; Kim, Yun Ik; Yang, Hei Chang

    1997-07-01

    Objectives of this study is the development of methodology by which assesses the optimization of Surveillance Test Interval(STI) and Allowed Outage Time(AOT) using PSA method that can supplement the current deterministic methods and the improvement of Korean nuclear power plants safety. In the first year of this study, the survey about the assessment methodologies, modeling and results performed by domestic and international researches are performed as the basic step before developing the assessment methodology of this study. The assessment methodology that supplement the revealed problems in many other studies is presented and the application of new methodology into the example system assures the feasibility of this method. In the second year of this study, the sensitivity analyses about the failure factors of the components are performed in the bases of the assessment methodologies of the first study, the interaction modeling of the STI and AOT is quantified. And the reliability assessment methodology about the diesel generator is reviewed and applied to the PSA code

  1. A study on assessment methodology of surveillance test interval and allowed outage time

    Energy Technology Data Exchange (ETDEWEB)

    Chung, Chang Hyun; You, Young Woo; Cho, Jae Seon; Huh, Chang Wook; Kim, Do Hyoung; Kim, Ju Youl; Kim, Yoon Ik; Yang, Hui Chang; Park, Kang Min [Seoul National Univ., Seoul (Korea, Republic of)

    1998-03-15

    The objectives of this study is the development of methodology by which assesses the optimization of Surveillance Test Internal(STI) and Allowed Outage Time(AOT) using PSA method that can supplement the current deterministic methods and the improvement of Korean nuclear power plant safety. In this study, the survey about the assessment methodologies, modelings and results performed by domestic and international researches are performed as the basic step before developing the assessment methodology of this study. The assessment methodology that supplement the revealed problems in many other studies is presented and the application of new methodology into the example system assures the feasibility of this method. The sensitivity analyses about the failure factors of the components are performed in the bases of the and AOT is quantified. And the reliability assessment methodology about the diesel generator is reviewed and applied to the PSA code. The qualitative assessment for the STI/AOR of RPS/ESFAS assured safety the most important system in the nuclear power plant are performed.

  2. A study on assessment methodology of surveillance test interval and Allowed Outage Time

    Energy Technology Data Exchange (ETDEWEB)

    Che, Moo Seong; Cheong, Chang Hyeon; Ryu, Yeong Woo; Cho, Jae Seon; Heo, Chang Wook; Kim, Do Hyeong; Kim, Joo Yeol; Kim, Yun Ik; Yang, Hei Chang [Seoul National Univ., Seoul (Korea, Republic of)

    1997-07-15

    Objectives of this study is the development of methodology by which assesses the optimization of Surveillance Test Interval(STI) and Allowed Outage Time(AOT) using PSA method that can supplement the current deterministic methods and the improvement of Korean nuclear power plants safety. In the first year of this study, the survey about the assessment methodologies, modeling and results performed by domestic and international researches are performed as the basic step before developing the assessment methodology of this study. The assessment methodology that supplement the revealed problems in many other studies is presented and the application of new methodology into the example system assures the feasibility of this method. In the second year of this study, the sensitivity analyses about the failure factors of the components are performed in the bases of the assessment methodologies of the first study, the interaction modeling of the STI and AOT is quantified. And the reliability assessment methodology about the diesel generator is reviewed and applied to the PSA code.

  3. Health impact assessment and monetary valuation of IQ loss in pre-school children due to lead exposure through locally produced food.

    Science.gov (United States)

    Bierkens, J; Buekers, J; Van Holderbeke, M; Torfs, R

    2012-01-01

    A case study has been performed which involved the full chain assessment from policy drivers to health effect quantification of lead exposure through locally produced food on loss of IQ in pre-school children at the population level across the EU-27, including monetary valuation of the estimated health impact. Main policy scenarios cover the period from 2000 to 2020 and include the most important Community policy developments expected to affect the environmental release of lead (Pb) and corresponding human exposure patterns. Three distinct scenarios were explored: the emission situation based on 2000 data, a business-as-usual scenario (BAU) up to 2010 and 2020 and a scenario incorporating the most likely technological change expected (Most Feasible Technical Reductions, MFTR) in response to current and future legislation. Consecutive model calculations (MSCE-HM, WATSON, XtraFOOD, IEUBK) were performed by different partners on the project as part of the full chain approach to derive estimates of blood lead (B-Pb) levels in children as a consequence of the consumption of local produce. The estimated B-Pb levels were translated into an average loss of IQ points/child using an empirical relationship based on a meta-analysis performed by Schwartz (1994). The calculated losses in IQ points were subsequently further translated into the average cost/child using a cost estimate of €10.000 per loss of IQ point based on data from a literature review. The estimated average reduction of cost/child (%) for all countries considered in 2010 under BAU and MFTR are 12.16 and 18.08% as compared to base line conditions, respectively. In 2020 the percentages amount to 20.19 and 23.39%. The case study provides an example of the full-chain impact pathway approach taking into account all foreseeable pathways both for assessing the environmental fate and the associated human exposure and the mode of toxic action to arrive at quantitative estimates of health impacts at the individual and

  4. A Tox21 Approach to Altered Epigenetic Landscapes: Assessing Epigenetic Toxicity Pathways Leading to Altered Gene Expression and Oncogenic Transformation In Vitro

    Directory of Open Access Journals (Sweden)

    Craig L. Parfett

    2017-06-01

    Full Text Available An emerging vision for toxicity testing in the 21st century foresees in vitro assays assuming the leading role in testing for chemical hazards, including testing for carcinogenicity. Toxicity will be determined by monitoring key steps in functionally validated molecular pathways, using tests designed to reveal chemically-induced perturbations that lead to adverse phenotypic endpoints in cultured human cells. Risk assessments would subsequently be derived from the causal in vitro endpoints and concentration vs. effect data extrapolated to human in vivo concentrations. Much direct experimental evidence now shows that disruption of epigenetic processes by chemicals is a carcinogenic mode of action that leads to altered gene functions playing causal roles in cancer initiation and progression. In assessing chemical safety, it would therefore be advantageous to consider an emerging class of carcinogens, the epigenotoxicants, with the ability to change chromatin and/or DNA marks by direct or indirect effects on the activities of enzymes (writers, erasers/editors, remodelers and readers that convey the epigenetic information. Evidence is reviewed supporting a strategy for in vitro hazard identification of carcinogens that induce toxicity through disturbance of functional epigenetic pathways in human somatic cells, leading to inactivated tumour suppressor genes and carcinogenesis. In the context of human cell transformation models, these in vitro pathway measurements ensure high biological relevance to the apical endpoint of cancer. Four causal mechanisms participating in pathways to persistent epigenetic gene silencing were considered: covalent histone modification, nucleosome remodeling, non-coding RNA interaction and DNA methylation. Within these four interacting mechanisms, 25 epigenetic toxicity pathway components (SET1, MLL1, KDM5, G9A, SUV39H1, SETDB1, EZH2, JMJD3, CBX7, CBX8, BMI, SUZ12, HP1, MPP8, DNMT1, DNMT3A, DNMT3B, TET1, MeCP2, SETDB2, BAZ2

  5. One- and multi-segment foot models lead to opposite results on ankle joint kinematics during gait: Implications for clinical assessment.

    Science.gov (United States)

    Pothrat, Claude; Authier, Guillaume; Viehweger, Elke; Berton, Eric; Rao, Guillaume

    2015-06-01

    Biomechanical models representing the foot as a single rigid segment are commonly used in clinical or sport evaluations. However, neglecting internal foot movements could lead to significant inaccuracies on ankle joint kinematics. The present study proposed an assessment of 3D ankle kinematic outputs using two distinct biomechanical models and their application in the clinical flat foot case. Results of the Plug in Gait (one segment foot model) and the Oxford Foot Model (multisegment foot model) were compared for normal children (9 participants) and flat feet children (9 participants). Repeated measures of Analysis of Variance have been performed to assess the Foot model and Group effects on ankle joint kinematics. Significant differences were observed between the two models for each group all along the gait cycle. In particular for the flat feet group, opposite results between the Oxford Foot Model and the Plug in Gait were revealed at heelstrike, with the Plug in Gait showing a 4.7° ankle dorsal flexion and 2.7° varus where the Oxford Foot Model showed a 4.8° ankle plantar flexion and 1.6° valgus. Ankle joint kinematics of the flat feet group was more affected by foot modeling than normal group. Foot modeling appeared to have a strong influence on resulting ankle kinematics. Moreover, our findings showed that this influence could vary depending on the population. Studies involving ankle joint kinematic assessment should take foot modeling with caution. Copyright © 2015 Elsevier Ltd. All rights reserved.

  6. Bearing performance degradation assessment based on time-frequency code features and SOM network

    International Nuclear Information System (INIS)

    Zhang, Yan; Tang, Baoping; Han, Yan; Deng, Lei

    2017-01-01

    Bearing performance degradation assessment and prognostics are extremely important in supporting maintenance decision and guaranteeing the system’s reliability. To achieve this goal, this paper proposes a novel feature extraction method for the degradation assessment and prognostics of bearings. Features of time-frequency codes (TFCs) are extracted from the time-frequency distribution using a hybrid procedure based on short-time Fourier transform (STFT) and non-negative matrix factorization (NMF) theory. An alternative way to design the health indicator is investigated by quantifying the similarity between feature vectors using a self-organizing map (SOM) network. On the basis of this idea, a new health indicator called time-frequency code quantification error (TFCQE) is proposed to assess the performance degradation of the bearing. This indicator is constructed based on the bearing real-time behavior and the SOM model that is previously trained with only the TFC vectors under the normal condition. Vibration signals collected from the bearing run-to-failure tests are used to validate the developed method. The comparison results demonstrate the superiority of the proposed TFCQE indicator over many other traditional features in terms of feature quality metrics, incipient degradation identification and achieving accurate prediction. Highlights • Time-frequency codes are extracted to reflect the signals’ characteristics. • SOM network served as a tool to quantify the similarity between feature vectors. • A new health indicator is proposed to demonstrate the whole stage of degradation development. • The method is useful for extracting the degradation features and detecting the incipient degradation. • The superiority of the proposed method is verified using experimental data. (paper)

  7. Gastric transit and small intestinal transit time and motility assessed by a magnet tracking system.

    Science.gov (United States)

    Worsøe, Jonas; Fynne, Lotte; Gregersen, Tine; Schlageter, Vincent; Christensen, Lisbet A; Dahlerup, Jens F; Rijkhoff, Nico J M; Laurberg, Søren; Krogh, Klaus

    2011-12-29

    Tracking an ingested magnet by the Magnet Tracking System MTS-1 (Motilis, Lausanne, Switzerland) is an easy and minimally-invasive method to assess gastrointestinal transit. The aim was to test the validity of MTS-1 for assessment of gastric transit time and small intestinal transit time, and to illustrate transit patterns detected by the system. A small magnet was ingested and tracked by an external matrix of 16 magnetic field sensors (4 × 4) giving a position defined by 5 coordinates (position: x, y, z, and angle: θ, φ). Eight healthy subjects were each investigated three times: (1) with a small magnet mounted on a capsule endoscope (PillCam); (2) with the magnet alone and the small intestine in the fasting state; and (3) with the magnet alone and the small intestine in the postprandial state. Experiment (1) showed good agreement and no systematic differences between MTS-1 and capsule endoscopy when assessing gastric transit (median difference 1 min; range: 0-6 min) and small intestinal transit time (median difference 0.5 min; range: 0-52 min). Comparing experiments (1) and (2) there were no systematic differences in gastric transit or small intestinal transit when using the magnet-PillCam unit and the much smaller magnetic pill. In experiments (2) and (3), short bursts of very fast movements lasting less than 5% of the time accounted for more than half the distance covered during the first two hours in the small intestine, irrespective of whether the small intestine was in the fasting or postprandial state. The mean contraction frequency in the small intestine was significantly lower in the fasting state than in the postprandial state (9.90 min-1 vs. 10.53 min-1) (p = 0.03). MTS-1 is reliable for determination of gastric transit and small intestinal transit time. It is possible to distinguish between the mean contraction frequency of small intestine in the fasting state and in the postprandial state.

  8. Withdrawal times and associated factors in colonoscopy: a quality assurance multicenter assessment.

    Science.gov (United States)

    Overholt, Bergein F; Brooks-Belli, Linda; Grace, Michael; Rankin, Kristin; Harrell, Royce; Turyk, Mary; Rosenberg, Fred B; Barish, Robert W; Gilinsky, Norman H

    2010-04-01

    To evaluate the use and impact of the recommended withdrawal time of at least 6 minutes from the cecum in colonoscopy in multiple gastroenterology endoscopy ambulatory surgery centers serving a wide geographical area. An observational prospective multicenter quality assurance review was conducted in 49 ambulatory surgery centers in 17 states with 315 gastroenterologists. There was no intervention with this quality assessment program as care of patients and the routine of gastroenterologists continued as standard practice. Multivariable analysis was applied to the database to examine factors affecting withdrawal time and polyp detection. There were 15,955 consecutive qualified patients receiving colonoscopies in a designated 4-week period. Gastroenterologists with average withdrawal times of 6 minutes or more in patients with no polyps were 1.8 times more likely to detect 1 or more polyps and had a significantly higher rate (Pquality assurance assessment from standard colonoscopy practices of 315 gastroenterologists in 49 endoscopic ambulatory surgery centers serving a wide geographical area provides support for the merits of a colonoscopy withdrawal time from the cecum of 6 minutes or more to improve the detection of polyps.

  9. Assessment of Tandem Measurements of pH and Total Gut Transit Time in Healthy Volunteers

    OpenAIRE

    Mikolajczyk, Adam E; Watson, Sydeaka; Surma, Bonnie L; Rubin, David T

    2015-01-01

    Objectives: The variation of luminal pH and transit time in an individual is unknown, yet is necessary to interpret single measurements. This study aimed to assess the intrasubject variability of gut pH and transit time in healthy volunteers using SmartPill devices (Covidien, Minneapolis, MN). Methods: Each subject (n=10) ingested two SmartPill devices separated by 24?h. Mean pH values were calculated for 30?min after gastric emptying (AGE), before the ileocecal (BIC) valve, after the ileocec...

  10. A real-time assessment of measurement uncertainty in the experimental characterization of sprays

    International Nuclear Information System (INIS)

    Panão, M R O; Moreira, A L N

    2008-01-01

    This work addresses the estimation of the measurement uncertainty of discrete probability distributions used in the characterization of sprays. A real-time assessment of this measurement uncertainty is further investigated, particularly concerning the informative quality of the measured distribution and the influence of acquiring additional information on the knowledge retrieved from statistical analysis. The informative quality is associated with the entropy concept as understood in information theory (Shannon entropy), normalized by the entropy of the most informative experiment. A new empirical correlation is derived between the error accuracy of a discrete cumulative probability distribution and the normalized Shannon entropy. The results include case studies using: (i) spray impingement measurements to study the applicability of the real-time assessment of measurement uncertainty, and (ii) the simulation of discrete probability distributions of unknown shape or function to test the applicability of the new correlation

  11. A generalised Dynamic Overflow Risk Assessment (DORA) for Real Time Control of urban drainage systems

    DEFF Research Database (Denmark)

    Vezzaro, Luca; Grum, Morten

    2014-01-01

    An innovative and generalised approach to the integrated Real Time Control of urban drainage systems is presented. The Dynamic Overflow Risk Assessment (DORA) strategy aims to minimise the expected Combined Sewer Overflow (CSO) risk by considering (i) the water volume presently stored in the drai......An innovative and generalised approach to the integrated Real Time Control of urban drainage systems is presented. The Dynamic Overflow Risk Assessment (DORA) strategy aims to minimise the expected Combined Sewer Overflow (CSO) risk by considering (i) the water volume presently stored...... and their uncertainty contributed to further improving the performance of drainage systems. The results of this paper will contribute to the wider usage of global RTC methods in the management of urban drainage networks....

  12. Staff, space, and time as dimensions of organizational slack: a psychometric assessment.

    Science.gov (United States)

    Mallidou, Anastasia A; Cummings, Greta G; Ginsburg, Liane R; Chuang, You-Ta; Kang, Sunghyun; Norton, Peter G; Estabrooks, Carole A

    2011-01-01

    : In the theoretical and research literature, organizational slack has been largely described in terms of financial resources and its impact on organizational outcomes. However, empirical research is limited by unclear definitions and lack of standardized measures. : The aim of this study was to assess the psychometric properties of a new organizational slack measure in health care settings. : A total of 752 nurses and 197 allied health care professionals (AHCPs) employed in seven pediatric Canadian hospitals completed the Alberta Context Tool, an instrument measuring organizational context, which includes the newly developed organizational slack measure. The nine-item, 5-point Likert organizational slack measure includes items assessing staff perceptions of available human resources (staffing), time, and space. We report psychometric assessments, bivariate analyses, and data aggregation indices for the measure. : The findings indicate that the measure has three subscales (staff, space, and time) with acceptable internal consistency reliability (alphas for staff, space, and time, respectively:.83,.63, and.74 for nurses;.81,.52, and.76 for AHCPs), links theory and hypotheses (construct validity), and is related to other relevant variables. Within-group reliability measures indicate stronger agreement among nurses than AHCPs, more reliable aggregation results in all three subscales at the unit versus facility level, and higher explained variance and validity of aggregated scores at the unit level. : The proposed organizational slack measure assesses modifiable organizational factors in hospitals and has the potential to explain variance in important health care system outcomes. Further assessments of the psychometric properties of the organizational slack measure in acute and long-term care facilities are underway.

  13. Who Leads China's Leading Universities?

    Science.gov (United States)

    Huang, Futao

    2017-01-01

    This study attempts to identify the major characteristics of two different groups of institutional leaders in China's leading universities. The study begins with a review of relevant literature and theory. Then, there is a brief introduction to the selection of party secretaries, deputy secretaries, presidents and vice presidents in leading…

  14. Assessment of Time-Lapse in Visible and Thermal Face Recognition

    Czech Academy of Sciences Publication Activity Database

    Farokhi, Sajad; Shamsuddin, Siti Mariyam; Flusser, Jan; Sheikh, Usman Ullah

    2012-01-01

    Roč. 6, č. 1 (2012), s. 181-186 R&D Projects: GA ČR GAP103/11/1552 Institutional support: RVO:67985556 Keywords : face recognition * moment invariants * Zernike moments Subject RIV: JD - Computer Applications, Robotics http://library.utia.cas.cz/separaty/2012/ZOI/flusser-assessment of time-lapse in visible and thermal face recognition -j.pdf

  15. Risk assessment of environmentally influenced airway diseases based on time-series analysis.

    Science.gov (United States)

    Herbarth, O

    1995-09-01

    Threshold values are of prime importance in providing a sound basis for public health decisions. A key issue is determining threshold or maximum exposure values for pollutants and assessing their potential health risks. Environmental epidemiology could be instrumental in assessing these levels, especially since the assessment of ambient exposures involves relatively low concentrations of pollutants. This paper presents a statistical method that allows the determination of threshold values as well as the assessment of the associated risk using a retrospective, longitudinal study design with a prospective follow-up. Morbidity data were analyzed using the Fourier method, a time-series analysis that is based on the assumption of a high temporal resolution of the data. This method eliminates time-dependent responses like temporal inhomogeneity and pseudocorrelation. The frequency of calls for respiratory distress conditions to the regional Mobile Medical Emergency Service (MMES) in the city of Leipzig were investigated. The entire population of Leipzig served as a pool for data collection. In addition to the collection of morbidity data, air pollution measurements were taken every 30 min for the entire study period using sulfur dioxide as the regional indicator variable. This approach allowed the calculation of a dose-response curve for respiratory diseases and air pollution indices in children and adults. Significantly higher morbidities were observed above a 24-hr mean value of 0.6 mg SO2/m3 air for children and 0.8 mg SO2/m3 for adults.(ABSTRACT TRUNCATED AT 250 WORDS)

  16. REAL-TIME ASSESSMENT OF MICROWAVE ABLATION EFFICACY BY NIR SPECTROSCOPIC TECHNIQUE

    Directory of Open Access Journals (Sweden)

    JINZHE ZHAO

    2014-01-01

    Full Text Available Microwave ablation (MWA status monitoring in real time plays a key role in assessment of therapeutic effectiveness. As a novel real-time assessment method, near infrared spectroscopy (NIRs was used to evaluate the ablation efficacy. MWA experiments were carried out on in vitro porcine livers. An optical measurement system for biological tissue is developed by our lab to monitor reduced scattering coefficient $(\\mu_{s}^{'}$ at 690 nm of the coagulation zones. It is noted that $\\mu_{s}^{'}$ of liver tissue, which increases as the liver tissue being ablated, is clearly related with the coagulation status. $\\mu_{s}^{'}$ of normal tissue and coagulated tissue is 3–5 and 17–19 cm-1, respectively. Continuous changes of $\\mu_{s}^{'}$ demonstrate that optical parameter can be used as an efficacy evaluation factor because it essentially indicates the degree of thermal damage. Compared with temperature, optical parameter is more sensitive and accurate, which is promising for real-time therapeutic efficacy assessment in MWA.

  17. Invited Commentary: Little Steps Lead to Huge Steps-It's Time to Make Physical Inactivity Our Number 1 Public Health Enemy.

    Science.gov (United States)

    Church, Timothy S

    2016-11-01

    The analysis plan and article in this issue of the Journal by Evenson et al. (Am J Epidemiol 2016;184(9):621-632) is well-conceived, thoughtfully conducted, and tightly written. The authors utilized the National Health and Nutrition Examination Survey data set to examine the association between accelerometer-measured physical activity level and mortality and found that meeting the 2013 federal Physical Activity Guidelines resulted in a 35% reduction in risk of mortality. The timing of these findings could not be better, given the ubiquitous nature of personal accelerometer devices. The masses are already equipped to routinely quantify their activity, and now we have the opportunity and responsibility to provide evidenced-based, tailored physical activity goals. We have evidenced-based physical activity guidelines, mass distribution of devices to track activity, and now scientific support indicating that meeting the physical activity goal, as assessed by these devices, has substantial health benefits. All of the pieces are in place to make physical inactivity a national priority, and we now have the opportunity to positively affect the health of millions of Americans. © The Author 2016. Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  18. Application and Assessment of Extension of Time Claim: Findings of Case Studies Conducted in Malaysia

    Directory of Open Access Journals (Sweden)

    M.S. Mohd Danuri,

    2006-12-01

    Full Text Available It is a common phenomenon for construction projects to have applications for extension of time. Many problems are encountered in practice in the application and preparation of extension of time claims. A study was conducted to identify the main problems encountered in the application and assessment of extension of time claim in selected construction projects in Malaysia. Three (3 case studies have been used 10 investigate the extension of time issues. Findings from the study revealed that local contractors usually fail to comply with the contract procedural requirements to submit timely notification of delay and have difficulty in demonstrating their entitlement for extension of time. The main problem faced by contract administrators is that contractors tend to "inflate" their extension of time entitlement with the intention to maximise their claims. Adherence to the agreed procedure in preparing and evaluating of delay claims and the implementation of a set of agreed standardised delay analysis may help to minimize the frequency and impact of such problems.

  19. A longitudinal assessment of sleep timing, circadian phase, and phase angle of entrainment across human adolescence.

    Directory of Open Access Journals (Sweden)

    Stephanie J Crowley

    Full Text Available The aim of this descriptive analysis was to examine sleep timing, circadian phase, and phase angle of entrainment across adolescence in a longitudinal study design. Ninety-four adolescents participated; 38 (21 boys were 9-10 years ("younger cohort" and 56 (30 boys were 15-16 years ("older cohort" at the baseline assessment. Participants completed a baseline and then follow-up assessments approximately every six months for 2.5 years. At each assessment, participants wore a wrist actigraph for at least one week at home to measure self-selected sleep timing before salivary dim light melatonin onset (DLMO phase - a marker of the circadian timing system - was measured in the laboratory. Weekday and weekend sleep onset and offset and weekend-weekday differences were derived from actigraphy. Phase angles were the time durations from DLMO to weekday sleep onset and offset times. Each cohort showed later sleep onset (weekend and weekday, later weekend sleep offset, and later DLMO with age. Weekday sleep offset shifted earlier with age in the younger cohort and later in the older cohort after age 17. Weekend-weekday sleep offset differences increased with age in the younger cohort and decreased in the older cohort after age 17. DLMO to sleep offset phase angle narrowed with age in the younger cohort and became broader in the older cohort. The older cohort had a wider sleep onset phase angle compared to the younger cohort; however, an age-related phase angle increase was seen in the younger cohort only. Individual differences were seen in these developmental trajectories. This descriptive study indicated that circadian phase and self-selected sleep delayed across adolescence, though school-day sleep offset advanced until no longer in high school, whereupon offset was later. Phase angle changes are described as an interaction of developmental changes in sleep regulation interacting with psychosocial factors (e.g., bedtime autonomy.

  20. Breath holding endurance: stability over time and relationship with self-assessed persistence

    Directory of Open Access Journals (Sweden)

    Daisy G.Y. Thompson-Lake

    2017-09-01

    Full Text Available Breath holding (BH endurance has been suggested as a measure of the distress tolerance that could predict the outcome of attempts to implement behavior changes, such as stopping smoking or illicit substance use. It is not known however, to what degree BH endurance is a variable trait that may vary depending on situational context, or a stable state characteristic. We measured BH in two groups of participants at baseline and 22 and 89 days (N = 62 and N = 41 post-baseline and in a third group at multiple times points across a 5-week period (N = 44. Participants also filled out a questionnaire created to assess their perceived persistence compared to peers. Correlations were found between baseline and final BH measures (r’s > 0.67, p’s < 0.0001 at all time points. When groups were combined, regardless of time point, Spearman’s rank correlation showed a strong positive correlation (rs = 0.66, p < 0.0001. Self-assessed persistence was not related to BH endurance. This study provides evidence of the stability of BH across time when tested under the same conditions in young adults. Further research is needed to clarify whether BH is linked to behavioral outcomes.