WorldWideScience

Sample records for assessing lead time

  1. Assessment of lead-time bias in estimates of relative survival for breast cancer.

    Science.gov (United States)

    Andersson, Therese M-L; Rutherford, Mark J; Humphreys, Keith

    2017-02-01

    Relative survival ratios (RSRs) can be useful for evaluating the impact of changes in cancer care on the prognosis of cancer patients or for comparing the prognosis for different subgroups of patients, but their use is problematic for cancer sites where screening has been introduced due to the potential of lead-time bias. Lead-time is survival time that is added to a patient's survival time because of an earlier diagnosis irrespective of a possibly postponed time of death. In the presence of screening it is difficult to disentangle how much of an observed improvement in survival is real and how much is due to lead-time bias. Even so, RSRs are often presented for breast cancer, a site where screening has led to early diagnosis, with the assumption that the lead-time bias is small. We describe a simulation-based framework for studying the lead-time bias due to mammography screening on RSRs of breast cancer based on a natural history model developed in a Swedish setting. We have performed simulations, using this framework, under different assumptions for screening sensitivity and breast cancer survival with the aim of estimating the lead-time bias. Screening every second year among ages 40-75 was introduced assuming that screening had no effect on survival, except for lead-time bias. Relative survival was estimated both with and without screening to enable quantification of the lead-time bias. Scenarios with low, moderate and high breast cancer survival, and low, moderate and high screening sensitivity were simulated, and the lead-time bias assessed in all scenarios. Copyright © 2016 Elsevier Ltd. All rights reserved.

  2. The impact of lead time reliability in freight transport: A logistics assessment of transport economics findings

    NARCIS (Netherlands)

    Dullaert, W.E.H.; Zamparini, L.

    2013-01-01

    This paper considers speed and reliability, measured by the average and variance of the lead time, to examine the relevance of the latter variable on inventory costs. By using a flexible simulation framework, it is shown that reducing variability does not necessarily reduce costs and might in fact

  3. 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

  4. Dedicated Research Time During Surgery Residency Leads to a Significant Decline In Self-Assessed Clinical Aptitude and Surgical Skills.

    Science.gov (United States)

    Grova, Monica M; Yang, Anthony D; Humphries, Misty D; Galante, Joseph M; Salcedo, Edgardo S

    The surgical community commonly perceives a decline in surgical and patient care skills among residents who take dedicated time away from clinical activity to engage in research. We hypothesize that residents perceive a decline in their skills because of dedicated research time. UC Davis Medical Center, Sacramento, CA, an institutional tertiary care center. General surgery residents and graduates from UC Davis general surgery residency training program, who had completed at least 1 year of research during their training. A total of 35 people were asked to complete the survey, and 19 people submitted a completed survey. Participants were invited to complete an online survey. Factors associated with the decline in skills following their research years were examined. All statistical analyses were performed with IBM SPSS Statistics software. A total of 19 current or former general surgery residents responded to the survey (54% response rate). Overall, 42% described their research as "basic science." Thirteen residents (68%) dedicated 1 year to research, while the remainder spent 2 or more years. Basic science researchers were significantly more likely to report a decrease in clinical judgment (75% vs. 22%, p = 0.013) as well as a decrease in patient care skills (63% vs. 0%, p = 0.002). Residents who dedicated at least 2 years to research were more likely to perceive a decline in overall aptitude and surgical skills (100% vs. 46%, p = 0.02), and a decline in patient care skills (67% vs. 8%, p = 0.007). Most residents who dedicate time for research perceive a decline in their overall clinical aptitude and surgical skills. This can have a dramatic effect on the confidence of these residents in caring for patients and leading a care team once they re-enter clinical training. Residents who engaged in 2 or more years of research were significantly more likely to perceive these problems. Further research should determine how to keep residents who are interested in academics

  5. Leading in Times of Crisis

    OpenAIRE

    Jungbauer, Kevin-Lim

    2016-01-01

    Crisis represents an important contextual variable in the leader-follower relationship. Never is it as important as in times of “shock” when followers experience intense uncertainty and seek for sources of protection and guidance, that leaders are required to step in and find appropriate ways to alleviate fears, restore a sense normalcy, and maintain effective functioning. Over the years, studies from multiple disciplines have accumulated to a large body of literature on the topic of crisis l...

  6. 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...

  7. 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...

  8. Optimal lead time for dengue forecast.

    Science.gov (United States)

    Hii, Yien Ling; Rocklöv, Joacim; Wall, Stig; Ng, Lee Ching; Tang, Choon Siang; Ng, Nawi

    2012-01-01

    A dengue early warning system aims to prevent a dengue outbreak by providing an accurate prediction of a rise in dengue cases and sufficient time to allow timely decisions and preventive measures to be taken by local authorities. This study seeks to identify the optimal lead time for warning of dengue cases in Singapore given the duration required by a local authority to curb an outbreak. We developed a Poisson regression model to analyze relative risks of dengue cases as functions of weekly mean temperature and cumulative rainfall with lag times of 1-5 months using spline functions. We examined the duration of vector control and cluster management in dengue clusters > = 10 cases from 2000 to 2010 and used the information as an indicative window of the time required to mitigate an outbreak. Finally, we assessed the gap between forecast and successful control to determine the optimal timing for issuing an early warning in the study area. Our findings show that increasing weekly mean temperature and cumulative rainfall precede risks of increasing dengue cases by 4-20 and 8-20 weeks, respectively. These lag times provided a forecast window of 1-5 months based on the observed weather data. Based on previous vector control operations, the time needed to curb dengue outbreaks ranged from 1-3 months with a median duration of 2 months. Thus, a dengue early warning forecast given 3 months ahead of the onset of a probable epidemic would give local authorities sufficient time to mitigate an outbreak. Optimal timing of a dengue forecast increases the functional value of an early warning system and enhances cost-effectiveness of vector control operations in response to forecasted risks. We emphasize the importance of considering the forecast-mitigation gaps in respective study areas when developing a dengue forecasting model.

  9. Assessment of lead in cosmetic products.

    Science.gov (United States)

    Al-Saleh, Iman; Al-Enazi, Sami; Shinwari, Neptune

    2009-07-01

    There have been a number of recent reports in the media and on the internet about the presence of lead in brand-names lipsticks. This has drawn our attention to assess the safety of various cheap brands of cosmetics sold at 2-riyals stores in Saudi market that are imported from countries where safety regulations are poorly enforced as well as they lack perfect conditions for manufacturing. Lead contents were determined in 26 and eight different brands of lipsticks and eye shadows using the Zeeman atomic absorption spectrophotometer coupled to graphite tube atomizer after an acid digestion procedure. Lead was detected in all the studied samples. The median (25th-75th percentile) lead content in 72 lipsticks samples was 0.73 (0.49-1.793) PPM wet wt. in the range of 0.27-3760 PPM wet wt. There were four brands of lipsticks with lead content above the FDA lead limit as impurities in color additives (20 PPM). The FDA does not set a limit for lead in lipstick. Three of them were extremely high points and considered outliers. The median (25th-75th percentile) lead contents in pressed powder eye shadow was 1.38 (0.944-1.854) PPM wet wt. (n=22) in the range of 0.42-58.7 PPM wet wt. One brand was above 20 PPM the US FDA's lead limit as impurities. The overall results indicate that lead in lipsticks and eye shadows are below the FDA lead limit as impurities and, thus, probably have no significant toxicological effects. Nevertheless, few brands had lead content above 20 PPM that might put consumers at the risk of lead poisoning. Lead is a cumulative, and applying lead-containing cosmetics several times a day or every day, can potentially add up to significant exposure levels. Pregnant and nursing mothers are vulnerable population because lead passes through placenta and human milk and affect fetus or infant's developments. Our findings call for an immediate mandatory regular testing program to check lead and other toxic metals in lipsticks and other cosmetic products imported

  10. Maritime Load Dependent Lead Times - An Analysis

    DEFF Research Database (Denmark)

    Pahl, Julia

    2017-01-01

    steps and increased container lead times. Proposed solutions to fight congestion range from extend-ing port capacities to process optimization of parts of the maritime supply chain. The potential that lies in information sharing and integrated planning using IT has received some attention, but mainly...... on the operational level concerning timely information sharing. Collaborative planning approaches for the maritime supply chain are scarce. The production industry already implemented planning and in-formation concepts. Problems related to the maritime supply chain have great similarities with those encountered...... 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....

  11. Maritime Load Dependent Lead Times - An Analysis

    DEFF Research Database (Denmark)

    Pahl, Julia; Voss, Stefan

    2017-01-01

    Traditionally, the maritime sector follows a very conservative approach towards sharing information and adopting information technology (IT) to stream-line logistic activities. Late arrivals of ships create problems especially with the trend to build large ships leading to peak loads of process...

  12. Improving Order Lead Time: A Case Study

    Science.gov (United States)

    Villarreal, Bernardo; Salido, Lucy

    2009-01-01

    A fundamental challenge of globally competing companies is to increase their level of customer satisfaction, by devising and implementing strategies aimed at providing better price, quality, and service. This paper describes the efforts of a Mexican company to achieve this goal, and in particular, with the need to decrease order lead time…

  13. 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...

  14. Modeling stochastic lead times in multi-echelon systems

    OpenAIRE

    Diks, EB Erik; Heijden, van der, ML

    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 defined, which is especially a problem for simulation modeling. In this paper, we use results from queuing theory to define a set of simple lead time processes guaranteeing that (a) orders do not c...

  15. Modeling stochastic lead times in multi-echelon systems

    NARCIS (Netherlands)

    Diks, E.B.; van der Heijden, Matthijs 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

  16. Editorial: Lead Risk Assessment and Health Effects.

    Science.gov (United States)

    Mielke, Howard W

    2016-06-14

    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.

  17. Assessment of lead contamination of the general environment through blood lead levels.

    Science.gov (United States)

    Zheng, X Q; Ji, R D

    1987-09-01

    More than 2000 blood samples were collected at random from full-time middle school teachers in 9 cities of China and analyzed for lead concentration with strict quality assurance procedures. Questionnaries about the smoking habits, alcohol consumption, residence condition, and fuel used at home were filled out by each person, and information about traffic, and lead concentration in different areas of the environment was also collected as far as possible. The result showed that the geometric mean of blood lead levels of teachers in different cities was ranging between 59-82 μg l(-1) among them the lowest levels were found in Nanjing and the highest in Shanghai. The difference between the lowest and the highest value was only 23 μg l(-1). Comparing with the results of WHO/UNEP and CEC projects. The overall geometric average blood level in China is lower than in all the other countries except Japan. It indicates that the lead pollution in the general environment of China was not as severe as in the participating countries of WHO/UNEP and CEC projects. This may be attributed by the following factors: The less automobile triffic, the larger proportion of non-leaded gasoline used and the less canned food consumption. Factors influencing the lead levels in blood were also analyzed and the 'normal value' (95% upper limit) of blood lead was assessed to be 160 μg l(-1).

  18. Leading Learning through Assessment for Learning?

    Science.gov (United States)

    Boyle, William Francis; Charles, Marie

    2010-01-01

    The article examines the origins and purposes of assessment for learning (AfL) within the National Curriculum Assessment context in England. As a part of the Primary Strategy, AfL became part of the government's drive to improve standards through measuring school outcomes. The authors describe their investigation into teachers' understandings of…

  19. 78 FR 38318 - Integrated Science Assessment for Lead

    Science.gov (United States)

    2013-06-26

    ... AGENCY Integrated Science Assessment for Lead AGENCY: Environmental Protection Agency (EPA). ACTION..., ``Integrated Science Assessment for Lead'' (EPA/600/R-10/075F). The document was prepared by the National... review of the national ambient air quality standards (NAAQS) for lead (Pb). DATES: The document will be...

  20. 76 FR 38650 - Draft Integrated Science Assessment for Lead

    Science.gov (United States)

    2011-07-01

    ... AGENCY Draft Integrated Science Assessment for Lead AGENCY: Environmental Protection Agency. ACTION... Draft Integrated Science Assessment for Lead'' (EPA/600/R-10/075A). The original Federal Register notice... Development as part of the review of the National Ambient Air Quality Standards (NAAQS) for Lead. DATES: The...

  1. Assessing Metal Mobilization from Industrially Lead ...

    Science.gov (United States)

    A series of leaching and partitioning tests (Toxicity Characteristic Leaching Procedure (TCLP), Synthetic Precipitation Leaching Procedure (SPLP), Controlled Acidity Leaching Protocol (CALP), Acid Neutralization Capacity (ANC), and sequential extraction) were applied to three different soils to study potential mobility of metals into groundwater. Two of these soils were lead (Pb)-contaminated soils (Hotspot 1 and Hotspot 2) collected from an urban site associated with lead smelting and other industrial operations. The third sample (Stockpile) was soil affected by previous contamination in the area, removed from residential properties, stockpiled, and selected to be used as fill material in the studied site. The TCLP and CALP showed that Pb could be released from both hotspots, but were not released in the acidic rainfall extraction fluid of the SPLP. The sequential extraction showed that Pb in the hotspot soils was associated with the carbonate fraction, while As was associated with the Fe and Mn oxides. The stockpile released traces of Pb or As in the TCLP and CALP, but the ANC only released Pb under acidic conditions and the SPLP did not release Pb or As. Overall, the projected repository with Stockpile would not pose imminent danger to groundwater because, under the expected environmental conditions, Pb and As tend to remain in the solid phase. The objectives of this study were to determine if the stockpiled soil was suitable for the intended fill purpo

  2. Lead

    Science.gov (United States)

    ... Test Safety Alert: Learn about CDC Recommendations Second Informational Call (CDC-RFA-17-1701PPHF17), April 5, 2017, ... CLPPP CAP Healthy Homes Assessment Tools Lead Health Literacy Initiative Refugee Tool Kit Resources Healthy Homes and ...

  3. Large N quantum time evolution beyond leading order

    Energy Technology Data Exchange (ETDEWEB)

    Ryzhov, Anton V.; Yaffe, Laurence G.

    2000-12-15

    For quantum theories with a classical limit (which includes the large N limits of typical field theories), we derive a hierarchy of evolution equations for equal time correlators which systematically incorporate corrections to the limiting classical evolution. Explicit expressions are given for next-to-leading order, and next-to-next-to-leading order time evolution. The large N limit of N-component vector models, and the usual semiclassical limit of point particle quantum mechanics are used as concrete examples. Our formulation directly exploits the appropriate group structure which underlies the construction of suitable coherent states and generates the classical phase space. We discuss the growth of truncation error with time, and argue that truncations of the large-N evolution equations are generically expected to be useful only for times short compared to a ''decoherence'' time which scales like N{sup 1/2}.

  4. Lead exposure assessment from study near a lead-acid battery factory in China.

    Science.gov (United States)

    Chen, Laiguo; Xu, Zhencheng; Liu, Ming; Huang, Yumei; Fan, Ruifang; Su, Yanhua; Hu, Guocheng; Peng, Xiaowu; Peng, Xiaochun

    2012-07-01

    The production of lead-acid battery in China covered about one-third of the world total output and there are more than 2000 lead-acid battery factories. They may cause the major environment lead pollution. Blood lead levels of several hundreds of residents were over 100 μg/L due to the waste discharges from a lead-acid battery factory in Heyuan, Guangdong province. This study aimed to find out the environmental lead sources, the human lead exposure pathways, and the amplitudes from a lead-acid battery factory. The study results showed that lead levels in soil, dust, tree leaves and human blood declined with the distances increased from the production site. Twenty nine of 32 participants had blood lead levels of over 100 μg/L with an exceptional high value of 639 μg/L for one child. This result suggested that the lead-acid battery production from this factory has caused the elevated lead levels in its neighboring environment and residents. Dust intake was the dominant exposure pathway for humans (over 90%). The lead levels found in adult and toddler (6.19 and 50.1 μg/kg/d, respectively) in the polluted area were far higher than the provisional tolerable weekly intake (PTWI) of 25 μg/kg body weight (translated into 3.5 μg/kg/d), which was established by the joint FAO/WHO Expert Committee. Blood lead levels within the family members were strongly correlated with the house dust lead levels. Our results in this study suggested that further studies in this area should be performed to assess human exposure and relevant human health risks from living close to lead-acid battery factories. Copyright © 2012 Elsevier B.V. All rights reserved.

  5. Leaded Paint in Cambodia—Pilot-scale Assessment

    Directory of Open Access Journals (Sweden)

    Sereyrath Lim

    2015-01-01

    Conclusion. Based on our pilot-scale assessment, high levels of lead appear to be common in enamel paints in Cambodia, and a fuller assessment of the situation is warranted. Import and production of such toxic products should be avoided and appropriate labeling and public warnings should be provided.

  6. Inventory management with substitution effects and endogenous lead time.:Inventory management with substitution effects and endogenous lead time.

    OpenAIRE

    Jalali, Hamed

    2017-01-01

    This PhD thesis is about multi item inventory management with customer-driven substitution or customer choice. In this setting, the company can only indirectly influence customer decisions by its marketing choices (e.g., price and quality of the products). We study the optimal pricing and assortment decisions of a manufacturing firm in this setting with fixed and load-dependent lead time.

  7. Influence of product return lead-time on inventory control

    OpenAIRE

    Zerhouni, Mohamed Hichem; Gayon, Jean-Philippe; Frein, Yannick

    2009-01-01

    International audience; We consider a production-inventory system with capacity constraint and item returns correlated to demand. The system is modelled by an M/M/1 make-to-stock queue with lost sales. A satisfied demand incurs an item return with a certain probability, after an exponentially distributed return lead-time. We distinguish two cases: When the number of items to be returned is observable and when it is not observable. For the first case, we partially characterize the optimal policy...

  8. Integrated Science Assessment (ISA) for Lead (Final Report ...

    Science.gov (United States)

    EPA announced the availability of the final report, Integrated Science Assessment (ISA) for Lead (Pb). This document represents a concise synthesis and evaluation of the most policy-relevant science and will ultimately provide the scientific bases for EPA’s decision regarding whether the current standards for Pb sufficiently protect public health and the environment. Lead (Pb) is one of six principal (or criteria) pollutants for which EPA has established NAAQS

  9. 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.

  10. [Risk assessment of renal dysfunction caused by occupational lead exposure].

    Science.gov (United States)

    Tian, Li-ting; Lei, Li-jian; Chang, Xiu-li; Jin, Tai-yi; Zheng, Guang; Guo, Wei-jun; Li, Hui-qi; Pan, Xiao-hai

    2010-03-01

    To assess the risk of renal dysfunction caused by occupational lead exposure through epidemiological investigation. The workers in a battery factory were selected as the subjects for the exposure and effect assessment. The occupational environmental monitoring data was collected and used to calculate the total external dose of lead. The relationship between external dose and internal dose of lead was analyzed. The external dose, blood lead (BPb) and urinary lead (UPb) were used as exposure biomarkers while the urinary N-acetyl-D-glucosaminidase (UNAG), and urinary albumin (UALB) were used as the effect biomarkers for the renal dysfunction caused by lead. Software of BMDS (BMDS 11311) was used to calculate BMD. The external and internal does of lead was positively correlated (BPb: r = 0.466, P < 0.01; UPb: r = 0.383, P < 0.01). The levels of BPb, UPb in exposure group (654.03 microg/L, 143.45 microg/g Cr) were significantly higher than those in the control group (57.12 microg/L, 7.20 microg/g Cr), so were UALB, UNAG; in addition, all of them presented significant dose-response relationship. The BPb BMD of UALB, UNAG were 607.76, 362.56 microg/L respectively and the UPb BMD of UALB, UNAG were 117.79, 78.79 microg/gCr respectively. Occupational lead exposure can cause renal dysfunction, which presents dose-response relationship; the risk assessment of renal dysfunction caused by occupational lead exposure is performed by BMD calculation of BPb and UPb.

  11. 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.

  12. 75 FR 8934 - Integrated Science Assessment for Lead (Pb)

    Science.gov (United States)

    2010-02-26

    ... Advisory Committee (CASAC), an independent science advisory committee mandated by the Clean Air Act and part of the EPA's Science Advisory Board (SAB), is charged with independent expert scientific review of... AGENCY Integrated Science Assessment for Lead (Pb) AGENCY: Environmental Protection Agency. ACTION...

  13. Integrated Science Assessment (ISA) for Lead (Final Report, Jul 2013)

    Science.gov (United States)

    EPA announced the availability of the final report, Integrated Science Assessment (ISA) for Lead (Pb). This document represents a concise synthesis and evaluation of the most policy-relevant science and will ultimately provide the scientific bases for EPA’s decision regard...

  14. 77 FR 5247 - Draft Integrated Science Assessment for Lead

    Science.gov (United States)

    2012-02-02

    ... policy, viewpoint, or determination. EPA will consider any public comments submitted in response to this... the submission of recent scientific information on specified topics. Soon after, a science policy... AGENCY Draft Integrated Science Assessment for Lead AGENCY: Environmental Protection Agency (EPA). ACTION...

  15. 76 FR 26284 - Draft Integrated Science Assessment for Lead (Pb)

    Science.gov (United States)

    2011-05-06

    ... workshop was held on May 10-11, 2010 (75 FR 20843) to discuss policy- relevant science to inform EPA's... AGENCY Draft Integrated Science Assessment for Lead (Pb) AGENCY: Environmental Protection Agency (EPA). ] ACTION: Notice of public comment period. SUMMARY: The U.S. Environmental Protection Agency (EPA) is...

  16. Assessment of lead, copper and zinc contamination of soil from ...

    African Journals Online (AJOL)

    The extent of heavy metal contamination viz. lead (Pb), copper (Cu) and zinc (Zn) in the soil of the University of Cape Coast School of Agricultural farmland, Ghana, were assessed. Thirty soil samples were taken from six demarcated areas in the farm. The mean metal concentrations (mean ± cv) and ranges of the metals ...

  17. 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.

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

    OpenAIRE

    H?bl, Alexander; Jodlbauer, Herbert; Altendorfer, Klaus

    2013-01-01

    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 an...

  19. Lead

    Science.gov (United States)

    ... is serious about making sure companies that break the law are held accountable In the past year, EPA ... the health effects of lead in drinking water The law mandates no-lead products for drinking water after ...

  20. An explicit analysis of the lead time syndrome: stability condition and performance evaluation

    NARCIS (Netherlands)

    Selçuk, B.; Adan, I.J.B.F.; de Kok, T.G.; Fransoo, J.C.

    2009-01-01

    Updating planned lead times in response to changing workload levels leads to erratic ordering behaviour, resulting in even larger variability in the workload levels and flow times. This phenomenon is called lead time syndrome, and describes the cyclic interaction between adaptive planned lead times

  1. Optimising seasonal streamflow forecast lead time for operational decision making in Australia

    Science.gov (United States)

    Schepen, Andrew; Zhao, Tongtiegang; Wang, Q. J.; Zhou, Senlin; Feikema, Paul

    2016-10-01

    Statistical seasonal forecasts of 3-month streamflow totals are released in Australia by the Bureau of Meteorology and updated on a monthly basis. The forecasts are often released in the second week of the forecast period, due to the onerous forecast production process. The current service relies on models built using data for complete calendar months, meaning the forecast production process cannot begin until the first day of the forecast period. Somehow, the bureau needs to transition to a service that provides forecasts before the beginning of the forecast period; timelier forecast release will become critical as sub-seasonal (monthly) forecasts are developed. Increasing the forecast lead time to one month ahead is not considered a viable option for Australian catchments that typically lack any predictability associated with snowmelt. The bureau's forecasts are built around Bayesian joint probability models that have antecedent streamflow, rainfall and climate indices as predictors. In this study, we adapt the modelling approach so that forecasts have any number of days of lead time. Daily streamflow and sea surface temperatures are used to develop predictors based on 28-day sliding windows. Forecasts are produced for 23 forecast locations with 0-14- and 21-day lead time. The forecasts are assessed in terms of continuous ranked probability score (CRPS) skill score and reliability metrics. CRPS skill scores, on average, reduce monotonically with increase in days of lead time, although both positive and negative differences are observed. Considering only skilful forecast locations, CRPS skill scores at 7-day lead time are reduced on average by 4 percentage points, with differences largely contained within +5 to -15 percentage points. A flexible forecasting system that allows for any number of days of lead time could benefit Australian seasonal streamflow forecast users by allowing more time for forecasts to be disseminated, comprehended and made use of prior to

  2. Time-varying interaction leads to amplitude death in coupled ...

    Indian Academy of Sciences (India)

    A new form of time-varying interaction in coupled oscillators is introduced. In this interaction, each individual oscillator has always time-independent self-feedback while its interaction with other oscillators are modulated with time-varying function. This interaction gives rise to a phenomenon called amplitude death even in ...

  3. Assessment of Lead Concentration in the Surface and Profile Soil

    OpenAIRE

    Alushllari, Mirela; Civici, Nikolla

    2016-01-01

    There is a lead in the earth of the crust, among other. Lead is widely used in industry for building construction, lead-acid batteries, bullets, shot, etc. Lead poisoning is an important environmental pollutant that can have life-long adverse health effects. Lead causes symptoms ranging from the loss of neurological function to death depending upon the extent and duration of exposure. The current study reports the determination of lead concentration in soil samples, distribution of lead on th...

  4. 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...... discusses whether they have reason to be uneasy. The answer is no. The risk of reversing previous recommendations due to the passing of time alone are not severely larger for hyperbolic discounting than it is for exponential discounting. And it can be managed by the same rules of precaution normally used...

  5. Lead Time and Overdiagnosis in Prostate-Specific Antigen Screening : Importance of Methods and Context

    NARCIS (Netherlands)

    Draisma, Gerrit; Etzioni, Ruth; Tsodikov, Alex; Mariotto, Angela; Wever, Elisabeth; Gulati, Roman; Feuer, Eric; de Koning, Harry

    2009-01-01

    Background The time by which prostate-specific antigen (PSA) screening advances prostate cancer diagnosis, called the lead time, has been reported by several studies, but results have varied widely, with mean lead times ranging from 3 to 12 years. A quantity that is closely linked with the lead time

  6. Hippocampal Spike-Timing Correlations Lead to Hexagonal Grid Fields

    Science.gov (United States)

    Monsalve-Mercado, Mauro M.; Leibold, Christian

    2017-07-01

    Space is represented in the mammalian brain by the activity of hippocampal place cells, as well as in their spike-timing correlations. Here, we propose a theory for how this temporal code is transformed to spatial firing rate patterns via spike-timing-dependent synaptic plasticity. The resulting dynamics of synaptic weights resembles well-known pattern formation models in which a lateral inhibition mechanism gives rise to a Turing instability. We identify parameter regimes in which hexagonal firing patterns develop as they have been found in medial entorhinal cortex.

  7. How superluminal motion can lead to backward time travel

    CERN Document Server

    Nemiroff, Robert J

    2015-01-01

    It is commonly asserted that superluminal particle motion can enable backward time travel, but little has been written providing details. It is shown here that the simplest example of a "closed loop" event -- a twin paradox scenario where a single spaceship both traveling out and returning back superluminally -- does {\\it not} result in that ship straightforwardly returning to its starting point before it left. However, a more complicated scenario -- one where the superluminal ship first arrives at an intermediate destination moving subluminally -- can result in backwards time travel. This intermediate step might seem physically inconsequential but is shown to break Lorentz-invariance and be oddly tied to the sudden creation of a pair of spacecraft, one of which remains and one of which annihilates with the original spacecraft.

  8. 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.

  9. 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.

  10. Assessing the sustainability of lead utilization in China.

    Science.gov (United States)

    Sun, Lingyu; Zhang, Chen; Li, Jinhui; Zeng, Xianlai

    2016-12-01

    Lead is not only one of heavy metals imposing environment and health risk, but also critical resource to maintain sustainable development of many industries. Recently, due to the shortage of fossil fuels, clean energy vehicles, including electric bicycle, have emerged and are widely adopted soon in the world. China became the world's largest producer of primary lead and a very significant consumer in the past decade, which has strained the supplies of China's lead deposits from lithosphere and boost the anthropogenic consumption of metallic lead and lead products. Here we summarize that China's lead demand will continually increase due to the rapid growth of electric vehicle, resulting in a short carrying duration of lead even with full lead recycling. With these applications increasing at an annual rate of 2%, the carrying duration of lead resource until 2030 will oblige that recycling rate should be not less than 90%. To sustain lead utilization in China, one approach would be to improve the utilization technology, collection system and recycling technology towards closed-loop supply chain. Other future endeavors should include optimizing lead industrial structure and development of new energy. Copyright © 2016 Elsevier Ltd. All rights reserved.

  11. Study of Client Reject Policies under Lead-Time and Price Dependent Demand

    OpenAIRE

    Albana, Abduh Sayid; Frein, Yannick; Hammami, Ramzi

    2016-01-01

    Delivery lead-time has become a factor of competitiveness for companies and an important criterion of purchase for the customers today. Thus, in order to increase their profit, companies must not focus only on price but also need to quote the right delivery lead time to their customers. Some authors to find a way in quoting the right delivery lead-time while considering an M/M/1 system. In M/M/1, all customers are accepted. This can lead to longer lead times in the queue. Firms can react by q...

  12. Assessment of the Radiation Attenuation Properties of Several Lead Free Composites by Monte Carlo Simulation

    Directory of Open Access Journals (Sweden)

    Kazempour M.

    2015-06-01

    Full Text Available Background: In diagnostic radiology lead apron, are usually used to protect patients and radiology staff against ionizing radiation. Lead apron is a desirable shield due to high absorption and effective attenuation of x-ray photons in the diagnostic radiology range. Objective: Although lead aprons have good radiation protection properties, in recent years, researchers have been looking for alternative materials to be used instead of lead apron because of some problems derived from lead-content of aprons. Because of its lead-content, these radiation protection garments are so heavy and uncomfortable for the staff to wear, particularly in long-time uses. In addition, lead is a toxic element and its disposal is associated with environmental and human-health hazards. Method: In this study, several new combinations of lead free materials ((W-Si, (W-Sn-Ba-EPVC , (W-Sn-Cd-EPVC have been investigated in the energy range of diagnostic radiology in two geometries: narrow and broad beam. Geometries of the radiation attenuation characteristics of these materials was assessed in 40, 60, 90 and 120 kVp and the results compared with those of some lead-containing materials ((Pb-Si, (Pb-EPVC. Results: Lead shields still provide better protection in low energies (below 40 kVp. Combination of W-Sn-Cd-EPVC has shown the best radiation attenuation features in 60 and 90 kVp and the composition of (W-Sn-Ba-EPVC represents the best attenuation in 120 kVp, even better than previously mentioned lead- containing composites. Conclusion: Lead free shields are completely effective for protection against X-ray energies in the range of 60 to 120 kVp.

  13. Assessment of the Radiation Attenuation Properties of Several Lead Free Composites by Monte Carlo Simulation.

    Science.gov (United States)

    Kazempour, M; Saeedimoghadam, M; Shekoohi Shooli, F; Shokrpour, N

    2015-06-01

    In diagnostic radiology lead apron, are usually used to protect patients and radiology staff against ionizing radiation. Lead apron is a desirable shield due to high absorption and effective attenuation of x-ray photons in the diagnostic radiology range. Although lead aprons have good radiation protection properties, in recent years, researchers have been looking for alternative materials to be used instead of lead apron because of some problems derived from lead-content of aprons. Because of its lead-content, these radiation protection garments are so heavy and uncomfortable for the staff to wear, particularly in long-time uses. In addition, lead is a toxic element and its disposal is associated with environmental and human-health hazards. In this study, several new combinations of lead free materials ((W-Si), (W-Sn-Ba-EPVC ), (W-Sn-Cd-EPVC)) have been investigated in the energy range of diagnostic radiology in two geometries: narrow and broad beam. Geometries of the radiation attenuation characteristics of these materials was assessed in 40, 60, 90 and 120 kVp and the results compared with those of some lead-containing materials ((Pb-Si), (Pb-EPVC)). Lead shields still provide better protection in low energies (below 40 kVp). Combination of W-Sn-Cd-EPVC has shown the best radiation attenuation features in 60 and 90 kVp and the composition of (W-Sn-Ba-EPVC) represents the best attenuation in 120 kVp, even better than previously mentioned lead- containing composites. Lead free shields are completely effective for protection against X-ray energies in the range of 60 to 120 kVp.

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

    African Journals Online (AJOL)

    ADOWIE PERE

    Lead is included in the formulation of several motor oils. Leaded gasoline has been phased out, but is still used in ... Human exposure to motor garage chemicals has been suggested to induce genotoxic effects (Oktem et al., ... by adding hydrogen peroxide and sodium hexametaphosphate and the resulting soil analysed by.

  15. An evaluation of eye tracking technology in the assessment of 12 lead electrocardiography interpretation.

    Science.gov (United States)

    Breen, Cathal J; Bond, Raymond; Finlay, Dewar

    2014-01-01

    This study investigated eye tracking technology for 12 lead electrocardiography interpretation to Healthcare Scientist students. Participants (n=33) interpreted ten 12 lead ECG recordings and randomized to receive objective individual appraisal on their efforts either by traditional didactic format or by eye tracker software. One hundred percent of participants reported the experience positively at improving their ECG interpretation competency. ECG analysis time ranged between 13.2 and 59.5s. The rhythm strip was the most common lead studied and fixated on for the longest duration (mean 9.9s). Lead I was studied for the shortest duration (mean 0.25s). Feedback using eye tracking data during ECG interpretation did not produce any significant variation between the assessment marks of the study and the control groups (p=0.32). Although the hypothesis of this study was rejected active teaching and early feedback practices are recommended within this discipline. Copyright © 2014 Elsevier Inc. All rights reserved.

  16. Fluoroscopic and electrical assessment of a series of defibrillation leads: prevalence of externalized conductors.

    Science.gov (United States)

    Kodoth, Vivek N; Hodkinson, Emily C; Noad, Rebecca L; Ashfield, Kyle P; Cromie, Nicholas A; McEneaney, David J; Wilson, Carol M; Roberts, Michael J D

    2012-12-01

    Insulation defects with externalized conductors have been reported in the St. Jude Riata(®)  family of defibrillation leads (St. Jude Medical, Sylmar, CA, USA). The objective of the Northern Ireland Riata(®)  lead screening program was to identify insulation defects and externalized conductors by systematic fluoroscopic and electrical assessment in a prospectively defined cohort of patients. We sought to estimate the prevalence, identify risk factors, and determine the natural history of this abnormality. All patients with a Riata(®)  lead under follow-up at the Royal Victoria Hospital were invited for fluoroscopic imaging and implantable cardioverter-defibrillator lead parameter checks. Fluoroscopic images were read independently by two cardiologists and the presence of externalized conductors was classified as positive, negative, or borderline. One hundred and sixty-five of 212 patients with a Riata lead were evaluated by fluoroscopy and lead parameter measurements. The mean duration after implantation was 3.98+/-1.43 years. After screening 25 (15%) patients were classified as positive, 137 (83%) negative, and three (1.8%) borderline. Time since implantation (P = 0.001), presence of a single coil lead (P = 0.042), and patient age (P = 0.034) were significantly associated with externalized conductors. The observed rate of externalized conductors was 26.9% for 8-French and 4.7% for 7-French leads. No leads that were identified prospectively with externalized conductors had electrical abnormalities. Seven of 25 (28%) patients had a defective lead extracted by the end of this screening period. A significant proportion (15%) of patients with a Riata lead had an insulation breach 4 years after implantation. High-resolution fluoroscopic imaging in at least two orthogonal views is required to identify this abnormality. ©2012, The Authors. Journal compilation ©2012 Wiley Periodicals, Inc.

  17. Assessment of lead sources for waterfowl in Alaska

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Exposure to detrimental concentrations of lead has been documented in waterfowl in Alaska. In spectacled eiders (Somateria fischeri) and long-tailed ducks (Clangula...

  18. Lead time and overdiagnosis in prostate-specific antigen screening: Importance of methods and context

    NARCIS (Netherlands)

    G. Draisma (Gerrit); R. Etzioni (Ruth); A. Tsodikov (Alex); A. Mariotto (Angela); E.M. Wever (Elisabeth); R. Gulati (Roman); E. Feuer (Eric); H.J. de Koning (Harry)

    2009-01-01

    textabstractBackground The time by which prostate-specific antigen (PSA) screening advances prostate cancer diagnosis, called the lead time, has been reported by several studies, but results have varied widely, with mean lead times ranging from 3 to 12 years. A quantity that is closely linked with

  19. Overdiagnosis associated with breast cancer screening: A simulation study to compare lead-time adjustment methods.

    Science.gov (United States)

    Seigneurin, A; Labarère, J; Duffy, S W; Colonna, M

    2015-12-01

    Estimating overdiagnosis associated with breast cancer screening may use annual incidence rates of cancer. We simulated populations invited to screening programmes to assess two lead-time adjustment methods. Overdiagnosis estimates were computed using the compensatory drop method, which considered the decrease in incidence of cancers among older age groups no longer offered screening, and the method based on the decrease in incidence of late-stage cancers. The true value of overdiagnosis was 0% in all the data sets simulated. The compensatory drop method yielded an overdiagnosis estimate of -0.1% (95% credibility interval -0.5% to 0.5%) when participation rates among the population and risk of cancers were constant. However, if participation rates increased with calendar year as well as risk of cancer with birth cohorts, the overdiagnosis estimated was 11.0% (10.5-11.6%). Using the method based on the incidence of early- and late-stage cancers, overdiagnosis estimates were 8.9% (8.5-9.3%) and 17.6% (17.4-17.9%) when participation rates and risks of cancer were constant or increased with time, respectively. Adjustment for lead time based on the compensatory drop method is accurate only when participation rates and risks of cancer remain constant, whereas the adjustment method based on the incidence of early- and late-stage cancers results in overestimating overdiagnosis regardless of stability of participation rates and breast cancer risk. Copyright © 2015 Elsevier Ltd. All rights reserved.

  20. 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...

  1. 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.

  2. Transvenous lead extraction at the time of cardiac implantable electronic device upgrade: Complexity, safety, and outcomes.

    Science.gov (United States)

    Barakat, Amr F; Wazni, Oussama M; Tarakji, Khaldoun; Saliba, Walid I; Nimri, Nayef; Rickard, John; Brunner, Michael; Bhargava, Mandeep; Kanj, Mohamed; Baranowski, Bryan; Martin, David O; Cantillon, Daniel; Callahan, Thomas; Dresing, Thomas; Niebauer, Mark; Chung, Mina; Lindsay, Bruce D; Wilkoff, Bruce; Hussein, Ayman A

    2017-12-01

    The practice of lead abandonment at the time of cardiac implantable electronic device upgrade remains a controversial topic but is affecting an increasing number of patients. Inherent risks include high-risk extractions of redundant leads when extraction is required at a later date. We aimed to report our experience with transvenous lead extraction (TLE) at the time of device upgrade. All consecutive TLE procedures at the time of device upgrade at the Cleveland Clinic between January 1, 1996 and December 31, 2012 were included (n = 503). Success and complications were defined according to the Heart Rhythm Society consensus document on TLE. There were a total of 984 leads in place, and 719 were targeted with extraction (589 pacer and 130 defibrillator leads, 63 of them being dual-coil leads). In all patients, TLEs aimed to avoid abandoning leads. Concomitant lead management issues included lead malfunction (15%), previously abandoned leads (9%), vascular access occlusion (6%), or leads on advisory (3%). In most procedures (75.4%), special extraction tools were needed. The complete procedural and clinical success rates were 96.6% and 97.2%, respectively. During planned extractions, damage of coexisting leads occurred in 19 patients (3.8%), eventually requiring extraction. The major and minor complication rates were 1% and 1.4%, respectively. In a high-volume center, TLEs at the time of device upgrade were successful in the vast majority of patients with a low complication rate. Copyright © 2017. Published by Elsevier Inc.

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

    African Journals Online (AJOL)

    ADOWIE PERE

    kg , and 61.0 – 491 mg/kg for <. 2000 µm, < 250 µm and < 75 µm ... factors considered were closeness to roadside commercial barbeque snacks points (e.g. for ..... erythrocyte oxidative stress in long-term low- level lead-exposed adolescent ...

  4. 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

    . 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...... and not by variations in data. High levels of overdiagnosis of cancer have usually been explained by detection of many slow-growing tumors with long lead-times. This theory can be tested by studying if slow-growing tumors accumulate in the absence of screening, which they don't. Thus, it is likely that the natural...... 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...

  5. 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 ...

  6. 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.

  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. Efficacy of Subcutaneous Electrocardiogram Leads for Synchronous Timing During Chronic Counterpulsation Therapy.

    Science.gov (United States)

    Carnahan, Stephen R; Koenig, Steven C; Sobieski, Michael A; Schumer, Erin M; Monreal, Gretel; Wang, Yu; Choi, Young; Meuris, Brek J; Tompkins, Landon H; Wu, Zhongjun J; Slaughter, Mark S; Giridharan, Guruprasad A

    Counterpulsation devices (CPDs) require an accurate, reliable electrocardiogram (ECG) waveform for triggering inflation and deflation. Surface electrodes are for short-term use, and transvenous/epicardial leads require invasive implant procedure. A subcutaneous ECG lead configuration was developed as an alternative approach for long-term use with timing mechanical circulatory support (MCS) devices. In this study, efficacy testing was completed by simultaneously recording ECG waveforms from clinical-grade epicardial (control) and subcutaneous (test) leads in chronic ischemic heart failure calves implanted with CPD for up to 30 days. Sensitivity and specificity of CPD triggering by R-wave detection was quantified for each lead configuration. The subcutaneous leads provided 98.9% positive predictive value and 98.9% sensitivity compared to the epicardial ECG leads. Lead migration (n = 1) and fracture (n = 1) were observed in only 2 of 40 implanted leads, without adversely impacting triggering efficacy due to lead redundancy. These findings demonstrate the efficacy of subcutaneous ECG leads for long-term CPD timing and potential use as an alternative method for MCS device timing.

  9. Asymptotic Optimality of Constant-Order Policies for Lost Sales Inventory Models with Large Lead Times

    OpenAIRE

    Goldberg, David A.; Katz-Rogozhnikov, Dmitriy A.; Lu, Yingdong; Sharma, Mayank; Squillante, Mark S.

    2012-01-01

    Lost sales inventory models with large lead times, which arise in many practical settings, are notoriously difficult to optimize due to the curse of dimensionality. In this paper we show that when lead times are large, a very simple constant-order policy, first studied by Reiman (\\cite{Reiman04}), performs nearly optimally. The main insight of our work is that when the lead time is very large, such a significant amount of randomness is injected into the system between when an order for more i...

  10. Overdiagnosis in breast cancer screening: the importance of length of observation period and lead time.

    Science.gov (United States)

    Duffy, Stephen W; Parmar, Dharmishta

    2013-05-16

    Overdiagnosis in breast cancer screening is a controversial topic. One difficulty in estimation of overdiagnosis is the separation of overdiagnosis from lead time that is the advance in the time of diagnosis of cancers, which confers an artificial increase in incidence when a screening programme is introduced. We postulated a female population aged 50-79 with a similar age structure and age-specific breast cancer incidence as in England and Wales before the screening programme. We then imposed a two-yearly screening programme; screening women aged 50-69, to run for twenty years, with exponentially distributed lead time with an average of 40 months in screen-detected cancers. We imposed no effect of the screening on incidence other than lead time. Comparison of age- and time-specific incidence between the screened and unscreened populations showed a major effect of lead time, which could only be adjusted for by follow-up for more than two decades and including ten years after the last screen. From lead time alone, twenty-year observation at ages 50-69 would confer an observed excess incidence of 37%. The excess would only fall below 10% with 25 years or more follow-up. For the excess to be nullified, we would require 30 year follow-up including observation up to 10 years above the upper age limit for screening. Studies using shorter observation periods will overestimate overdiagnosis by inclusion of cancers diagnosed early due to lead time among the nominally overdiagnosed tumours.

  11. [Assessment of cadmium and lead released from cigarette smoke].

    Science.gov (United States)

    Suna, S; Asakawa, F; Jitsunari, F; Manabe, Y; Gotou, A; Fukunaga, I; Nakajima, T

    1991-12-01

    Cigarette smoke, which contains many harmful compounds, affects not only the smoker's health but also indoor air quality. To evaluate indoor air contamination by cadmium (Cd) and lead (Pb), we measured Cd and Pb contained in the mainstream and sidestream smoke exhaled by experimental smoking of Japanese cigarettes and also determined urinary and blood Cd and Pb levels in smokers and non-smokers and air Cd and Pb levels in smoky environments. 1. One cigarette of each of 7 Japanese brands contained about 1 microgram each of Cd and Pb, of which about 50 ng each was released to the mainstream and 250 ng of Cd and 50 ng of Pb to the sidestream by smoking. 2. The blood Cd level in the smokers was significantly higher than that in the non-smokers. The urinary Cd level in the smokers was slightly higher than that in the non-smokers. The blood Cd level was related to the number of cigarettes smoked daily. Blood and urinary Pb levels did not differ between the smokers and non-smokers, but the blood Pb level was also related to the number of cigarettes smoked daily. 3. The air Cd levels in smoky places such as the smoking car of the special express train, an office, and a pachinko parlor were markedly higher than that in outdoor air. The air Cd concentration was well correlated with the environmental tobacco smoke concentration. On the other hand, the air Pb level was slightly higher in the above smoky places than outdoors. The mean air Pb concentration was not correlated with the environmental tobacco smoke concentration but was higher at higher environmental tobacco smoke concentration in each place.

  12. Lead time and overdiagnosis in prostate-specific antigen screening: Importance of methods and context

    National Research Council Canada - National Science Library

    isma, Gerrit; Etzioni, Ruth; Tsodikov, Alex; Mariotto, Angela; Wever, Elisabeth; Gulati, Roman; Feuer, Eric; Koning, Harry

    2009-01-01

    .... A quantity that is closely linked with the lead time is the overdiagnosis frequency, which is the fraction of screen-detected cancers that would not have been diagnosed in the absence of screening...

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

    Science.gov (United States)

    Luo, Nan; Li, Minghui; Stolk, Elly A; Devlin, Nancy J

    2013-07-01

    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. Using two general population samples, we compared three lead-time TTO variants: 10 years of lead time in full health preceding 5 years of unhealthy time (standard); 5 years of lead time preceding 5 years of unhealthy time (experimental); and 10 years of lead time and 5 years of unhealthy time, presented with a visual aid to highlight the point where the lead time ends (experimental). Participants were randomized to receive one of the lead-time variants, as administered by a computer software program. Health-state values generated by TTO valuation tasks using a longer lead time were slightly lower than those generated by tasks using a shorter lead time. When lead time and unhealthy time were presented with visual aids highlighting the difference between the lead time and unhealthy time, respondents spent more time considering health states with a value close to 0. Different lead-time time trade-off variants should be carefully studied in order to achieve the best measurement of health-state values using this new method.

  14. Quality Assessment of Meta-analyses Published in Leading Anesthesiology Journals From 2005 to 2014.

    Science.gov (United States)

    Hall, Amber M; Lee, Sandra; Zurakowski, David

    2017-06-01

    Meta-analysis, when preceded by a systematic review, is considered the "gold standard" in data aggregation; however, the quality of meta-analyses is often questionable, leading to uncertainty about the accuracy of results. In this study, we evaluate the quality of meta-analyses published in 5 leading anesthesiology journals from 2005 to 2014. A total of 220 meta-analyses published in Anesthesiology, Pain, British Journal of Anaesthesia, Anaesthesia, or Anesthesia & Analgesia were identified for inclusion. The quality of each meta-analysis was determined using the Revised Assessment of Multiple Systematic Reviews (R-AMSTAR). R-AMSTAR rated 11 questions related to systematic reviews and meta-analyses on a scale of 1-4, with 4 representing the highest quality. Overall meta-analyses quality was evaluated using a Spearmen regression analysis and found to positively correlate with time (rs = 0.24, P journals has increased over the last decade. Furthermore, assessing the scientific quality of included studies in meta-analyses (P = .60) and using this assessment to formulate conclusions and/or recommendations (P = .67) remains relatively low (median R-AMSTAR: 2, interquartile range [IQR]: 2-3]; median R-AMSTAR: 2, IQR: 1-2, respectively).

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

    OpenAIRE

    Luo, Nan; Li, Minghui; Stolk, Elly; 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. __Methods__ Using two general population samples, we compared three lead-time TTO variants: 10 years of lead time in full health preceding 5 years of unhealthy time (standard); 5 years of lead time prece...

  16. 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.

  17. Multi-Objective Lead-Time Control Problem with Stochastic Constraints

    Directory of Open Access Journals (Sweden)

    M. Molavi

    2014-10-01

    Full Text Available This research intends to find out any development of a robust multi-objective for lead time optimal control problem in a multi-stage assembly system model. Assembly system modeling is possible by the help of the open queue network. A working station includes one or infinite servers and just manufacturing or assembly operations are performed therein. Each part has a separate entry process and independent of each other. It is completely based upon Poisson process.Serving Lead Time of Stations are also independent of each other and therefore exponential distribution of each parameter is controllable. All stations have bounded uncertain unrecyclable wastes which are completely independent in compliance with Erlang distribution. Uncertainty in the problem parameters has been suggested as robust multi-objective optimal control model in which we have three incompatible target functions including cyclic operation cost minimization, average lead time minimization and lead time variance. Finally, target progress method has been applied in order to achieve serving optimal speeds and solve discrete time of the main problem approximately. The proposed model could present a suitable solution even for the same problem as mentioned in other related papers along with some considerable results in parameter uncertainty conditions.

  18. A System for Continuous Hydrological Ensemble Forecasting (SCHEF) to lead times of 9 days

    Science.gov (United States)

    Bennett, James C.; Robertson, David E.; Shrestha, Durga Lal; Wang, Q. J.; Enever, David; Hapuarachchi, Prasantha; Tuteja, Narendra K.

    2014-11-01

    This study describes a System for Continuous Hydrological Ensemble Forecasting (SCHEF) designed to forecast streamflows to lead times of 9 days. SCHEF is intended to support optimal management of water resources for consumptive and environmental purposes and ultimately to support the management of impending floods. Deterministic rainfall forecasts from the ACCESS-G numerical weather prediction (NWP) model are post-processed using a Bayesian joint probability model to correct biases and quantify uncertainty. Realistic temporal and spatial characteristics are instilled in the rainfall forecast ensemble with the Schaake shuffle. The ensemble rainfall forecasts are then used as inputs to the GR4H hydrological model to produce streamflow forecasts. A hydrological error correction is applied to ensure forecasts transit smoothly from recent streamflow observations. SCHEF forecasts streamflows skilfully for a range of hydrological and climate conditions. Skill is particularly evident in forecasts of streamflows at lead times of 1-6 days. Forecasts perform best in temperate perennially flowing rivers, while forecasts are poorest in intermittently flowing rivers. The poor streamflow forecasts in intermittent rivers are primarily the result of poor rainfall forecasts, rather than an inadequate representation of hydrological processes. Forecast uncertainty becomes more reliably quantified at longer lead times; however there is considerable scope for improving the reliability of streamflow forecasts at all lead times. Additionally, we show that the choice of forecast time-step can influence forecast accuracy: forecasts generated at a 1-h time-step tend to be more accurate than at longer time-steps (e.g. 1-day). This is largely because at shorter time-steps the hydrological error correction is able to correct streamflow forecasts with more recent information, rather than the ability of GR4H to simulate hydrological processes better at shorter time-steps. SCHEF will form the

  19. 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.

  20. Sensitivity of a thermodynamic sea ice model with leads to time step size

    Science.gov (United States)

    Ledley, T. S.

    1985-01-01

    The characteristics of sea ice models, developed to study the physics of the growth and melt of ice at the ocean surface and the variations in ice extent, depend on the size of the time step. Thus, to study longer-term variations within a reasonable computer budget, a model with a scheme allowing longer time steps has been constructed. However, the results produced by the model can definitely depend on the length of the time step. The sensitivity of a model to time-step size can be reduced by appropriate approaches. The present investigation is concerned with experiments which use a formulation of a lead parameterization that can be considered as a first step toward the development of a lead parameterization suitable for a use in long-term climate studies.

  1. 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.

  2. 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....

  3. 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.

  4. 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

  5. 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

  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. Computing the non-stationary replenishment cycle inventory policy under stochastic supplier lead-times

    NARCIS (Netherlands)

    Rossi, R.; Tarim, S.A.; Hnich, B.; Prestwich, S.

    2010-01-01

    In this paper we address the general multi-period production/inventory problem with non-stationary stochastic demand and supplier lead-time under service level constraints. A replenishment cycle policy (Rn,Sn) is modeled, where Rn is the nth replenishment cycle length and Sn is the respective

  8. 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.

  9. Real-Time Observation of Organic Cation Reorientation in Methylammonium Lead Iodide Perovskites

    NARCIS (Netherlands)

    Bakulin, Artem A.; Selig, Oleg; Bakker, Huib J.; Rezus, Yves L. A.; Mueller, Christian; Glaser, Tobias; Lovrincic, Robert; Sun, Zhenhua; Chen, Zhuoying; Walsh, Aron; Frost, Jarvist M.; Jansen, Thomas L. C.

    2015-01-01

    The introduction of a mobile and polarized organic moiety as a cation in 3D lead-iodide perovskites brings fascinating optoelectronic properties to these materials. The extent and the time scales of the orientational mobility of the organic cation and the molecular mechanism behind its motion remain

  10. A PROBABILISTIC INVENTORY MODEL FOR CONDITIONAL CREDIT PERIOD AND LEAD TIME WITH MULTIPLE STORAGE FACILITIES

    OpenAIRE

    Mishra, S.S.; Himanshu Pandey; Singh, R.S.

    2008-01-01

    A probabilistic inventory model for conditional credit period with exponential demand, non-zero lead time and multiple storage facility has been developed. The behaviour of total expected cost (TEC) has been examined and the use and application of the model is demonstrated with the help of a numerical example.

  11. 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

  12. The Repair Kit Problem with positive replenishment lead times and fixed ordering costs

    NARCIS (Netherlands)

    Prak, Derk; Saccani, Nicola; Syntetos, Aris A.; Teunter, Rudolf; Visintin, Filippo

    2017-01-01

    The Repair Kit Problem (RKP) concerns the determination of a set of items taken by a service engineer to perform on-site product support. Such a set is called a kit. Models developed in the literature have always ignored the lead times associated with delivering items to replenish the kit, thereby

  13. A Modified Delphi Process to Define Competencies for Assessment Leads Supporting a Doctor of Pharmacy Program.

    Science.gov (United States)

    Janke, Kristin K; Kelley, Katherine A; Sweet, Burgunda V; Kuba, Sarah E

    2016-12-25

    Objective. To define the competencies for individuals designated as assessment leads in colleges and schools of pharmacy. Methods. Twenty-three assessment experts in pharmacy participated in a modified Delphi process to describe competencies for an assessment lead, defined as the individual responsible for curricular assessment and assessment-related to doctor of pharmacy program accreditation. Round 1 asked open-ended questions about knowledge, skills, and attitudes. Round 2 grouped responses for comment and rating for consensus, which was prospectively set at 80%. Results. Twelve competencies were defined and grouped into 3 areas: Context for Assessment, Managing the Process of Assessment, and Leadership of Assessment Activities. In order to verify the panel's work, assessment competencies from other disciplines were reviewed and compared. Conclusions. The competencies describe roles for assessment professionals as experts, managers, and leaders of assessment processes. They can be used by assessment professionals in self-assessing areas for professional development and by administrators in selecting, developing, and supporting designated leads.

  14. Acute toxicity assessment of crude lead-extract from electronic waste ...

    African Journals Online (AJOL)

    Lead, with its toxic emission and pollution, is one of the hazardous chemical components of electronic wastes (e-wastes) rapidly generated in developing countries. This study assessed the environmental health effects of crude lead extracted from e-wastes materials, as determined by its acute toxicity (rat, oral). Diluted ...

  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. 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.

  17. HEADWAY TIME AND CRASHES AMONG NOVICE TEENS AND EXPERIENCED ADULT DRIVERS IN A SIMULATED LEAD TRUCK BRAKING SCENARIO.

    Science.gov (United States)

    McDonald, Catherine C; Seacrist, Thomas S; Lee, Yi-Ching; Loeb, Helen; Kandadai, Venk; Winston, Flaura K

    2013-01-01

    Driving simulators can be used to evaluate driving performance under controlled, safe conditions. Teen drivers are at particular risk for motor vehicle crashes and simulated driving can provide important information on performance. We developed a new simulator protocol, the Simulated Driving Assessment (SDA), with the goal of providing a new tool for driver assessment and a common outcome measure for evaluation of training programs. As an initial effort to examine the validity of the SDA to differentiate performance according to experience, this analysis compared driving behaviors and crashes between novice teens (n=20) and experienced adults (n=17) on a high fidelity simulator for one common crash scenario, a rear-end crash. We examined headway time and crashes during a lead truck with sudden braking event in our SDA. We found that 35% of the novice teens crashed and none of the experienced adults crashed in this lead truck braking event; 50% of the teens versus 25% of the adults had a headway time headway time, 70% crashed. Among all participants with a headway time of 2-3 seconds, further investigation revealed descriptive differences in throttle position and brake pedal force when comparing teens who crashed, teens who did not crash and adults (none of whom crashed). Even with a relatively small sample, we found statistically significant differences in headway time for adults and teens, providing preliminary construct validation for our new SDA.

  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. The ρ-meson time-like form factors in sub-leading pQCD

    Directory of Open Access Journals (Sweden)

    J.P.B.C. de Melo

    2016-12-01

    Full Text Available The annihilation/production process e++e−→ρ++ρ− is studied with respect to the universal perturbative QCD (pQCD predictions. Sub-leading contributions are considered together with the universal leading pQCD amplitudes such that the matrix elements of the ρ-meson electromagnetic current satisfy the constraint from the light-front angular condition. The data from the BaBar collaboration for the time-like ρ-meson form factors at s=10.58 GeV puts a stringent test to the onset of asymptotic pQCD behavior. The e++e−→ρ++ρ− cross-section for s between 60 GeV2 and 160 GeV2 is predicted where the sub-leading contributions are still considerable.

  20. 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...

  1. 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.

  2. [Eco-fitness of county-level agricultural leading industry structure: assessment and development prediction].

    Science.gov (United States)

    Wang, Liang; Zhu, Li-Qun; Zhang, Si-Wei; Zhang, Pei-Qi; Xu, Min-Lun; Bian, Xin-Min

    2012-11-01

    Based on the 'three critical points' theory of eco-fitness, and by using dynamic weighting and fitting methods, an assessment system for the eco-fitness of county-level agricultural leading industry structure was constructed, and, taking Zhangqiu of Shandong Province, East China as a case, the eco-fitness of county-level agricultural leading industry structure was assessed and predicted. Due to the limited agro-ecological resources, the comprehensive eco-fitness index of four kinds of agricultural leading industry in Zhangqiu presented an upward trend from 2005 to 2010, but a downward trend from 2011 to 2015. The eco-fitness indices of oil crops and fruits would be negative in 2015. The applied research in Zhangqiu confirmed the validity of the assessment system constructed for the eco-fitness of county-level agriculture leading industry structure and the rationality of the prediction model.

  3. 75 FR 69078 - Workshop To Review Draft Materials for the Lead (Pb) Integrated Science Assessment (ISA)

    Science.gov (United States)

    2010-11-10

    ... AGENCY Workshop To Review Draft Materials for the Lead (Pb) Integrated Science Assessment (ISA) AGENCY... a workshop to evaluate initial draft materials for the Pb Integrated Science Assessment (ISA) is... the scientific content of initial draft materials or sections for the draft ISA. Workshop sessions...

  4. 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.

  5. Sustainable EOQ under Lead-Time Uncertainty and Multi-Modal Transport

    Directory of Open Access Journals (Sweden)

    Soon-Kyo Lee

    2017-03-01

    Full Text Available In this paper, we examine a sustainable economic order quantity (S-EOQ problem with a stochastic lead-time and multi-modal transportation options. With the S-EOQ, decisions of order quantities, as well as a reorder point could be influenced by various factors, including unit price, stock-out cost, lead-time variability and emission costs. For a better understanding, we present a mathematical model of the concomitant S-EOQ problem and, using numerical experiments, explore various scenarios to determine the effects of incorporating sustainability considerations into the traditional inventory model on operational decisions including the choice of transportation modal combination and the sourcing decisions

  6. Simulation study of a basic integrated inventory problem with quality improvement and lead time reduction

    OpenAIRE

    Van Volsem, Sofie; Verdiesen, Johannes

    2010-01-01

    In this paper, we investigate the trade-off between investing in product quality improvement and lead time reduction in a B2B single-supplier, single-buyer environment. To this end, a discrete event simulation model is proposed, based on the integrated inventory model defined in Ouyang et al. (2006). Furthermore, the possibility of using alternative failure mechanisms and capital investment functions are studied. ity of using alternative failure mechanisms and capital investment functions...

  7. 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

  8. 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.

  9. Application of six sigma and AHP in analysis of variable lead time calibration process instrumentation

    Science.gov (United States)

    Rimantho, Dino; Rahman, Tomy Abdul; Cahyadi, Bambang; Tina Hernawati, S.

    2017-02-01

    Calibration of instrumentation equipment in the pharmaceutical industry is an important activity to determine the true value of a measurement. Preliminary studies indicated that occur lead-time calibration resulted in disruption of production and laboratory activities. This study aimed to analyze the causes of lead-time calibration. Several methods used in this study such as, Six Sigma in order to determine the capability process of the calibration instrumentation of equipment. Furthermore, the method of brainstorming, Pareto diagrams, and Fishbone diagrams were used to identify and analyze the problems. Then, the method of Hierarchy Analytical Process (AHP) was used to create a hierarchical structure and prioritize problems. The results showed that the value of DPMO around 40769.23 which was equivalent to the level of sigma in calibration equipment approximately 3,24σ. This indicated the need for improvements in the calibration process. Furthermore, the determination of problem-solving strategies Lead Time Calibration such as, shortens the schedule preventive maintenance, increase the number of instrument Calibrators, and train personnel. Test results on the consistency of the whole matrix of pairwise comparisons and consistency test showed the value of hierarchy the CR below 0.1.

  10. 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.

  11. Optimal Decision for Fashion Supply Chains with Service Level Constraint and Controllable Lead Time

    Directory of Open Access Journals (Sweden)

    Guo Li

    2015-01-01

    Full Text Available We study a two-echelon supply chain inventory model with controllable lead time and service level constraint in fashion supply chains, in which we assume that the unit cost of compressing lead time follows exponential distribution. Under these conditions we investigate the optimal ordering quantity and production quantity in the fashion supply chain by minimizing the joint total cost. Simultaneously, we work out the boundaries of ordering quantity and production quantity, which simplify the computation. Furthermore, numerical examples are presented to test the feasibility of the model. The results show that assuming the unit cost of compressing lead time in accordance with exponential distribution is realistic. It also notices that the optimal order and production decision for fashion supply chains are constrained obviously by the service level and safety factors. What is more, the holding cost rate of both the service level and safety factors has a certain influence on it. And by further analyzing on some references in the last part, we have done some extensions and found some interesting results.

  12. Assessing multi-tissue lead burdens in free-flying obligate scavengers in eastern North America.

    Science.gov (United States)

    Behmke, Shannon; Mazik, Patricia; Katzner, Todd

    2017-04-01

    Avian scavengers are regularly exposed to anthropogenic lead. Although many studies evaluate lead concentrations of either blood or tissues of lead-poisoned birds, there is comparatively less research on lead burdens of free-flying, apparently healthy individuals and populations. Here, we address this lack of information by assessing lead levels of multiple tissues (femur, liver, kidney, breast muscle, thigh muscle) in free-flying black vultures (n = 98) and turkey vultures (n = 10) collected outside the hunting season. We found only one individual had a soft tissue lead concentration indicative of acute exposure (6.17 mg/kg wet weight in the liver), while the other 107 vultures showed consistent low-level lead exposure throughout the soft tissues. All vultures, however, had femur lead concentrations indicative of chronic lead exposure (black vultures [Formula: see text]31.80 ± 20.42 mg/kg (±SD); turkey vultures 23.21 ± 18.77 mg/kg). Lead levels were similar in all tissues in both vulture species (in each case, p > 0.05) and were generally highest in the femur, intermediate in the kidney and liver, and lowest in the breast and thigh muscle. Despite the consistency of these patterns, there were few strong correlations between lead levels in different tissues within each species, and those correlations that did exist were not consistent between species. Because these vultures were free flying and apparently healthy, the organism-wide lead distributions and between-species trends we report here provide important insight into the sublethal lead burdens that black vultures and turkey vultures commonly carry. Furthermore, these data offer a framework to better interpret and contextualize lead exposure data collected from these and other species.

  13. 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....

  14. Leading effective virtual teams overcoming time and distance to achieve exceptional results

    CERN Document Server

    Settle-Murphy, Nancy M

    2013-01-01

    A proliferation of new technologies has lulled many into thinking that we actually have to think less about how we communicate. In fact, communicating and collaborating across time, distance, and cultures has never been more complex or difficult.Written as a series of bulleted tips drawn from client experiences and best practices, Leading Effective Virtual Teams: Overcoming Time and Distance to Achieve Exceptional Results presents practical tips to help leaders engage and motivate their geographically dispersed project team members. If you're a leader of any type of virtual team and want to he

  15. 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... Urban Development Office of the Secretary, Department of Housing and Urban Development LEAD-BASED PAINT POISONING PREVENTION IN CERTAIN RESIDENTIAL STRUCTURES Methods and Standards for Lead-Paint Hazard...

  16. 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.

  17. Slow Dynamic Processes in Lead Halide Perovskite Solar Cells. Characteristic Times and Hysteresis.

    Science.gov (United States)

    Sanchez, Rafael S; Gonzalez-Pedro, Victoria; Lee, Jin-Wook; Park, Nam-Gyu; Kang, Yong Soo; Mora-Sero, Ivan; Bisquert, Juan

    2014-07-03

    Characteristic times of perovskite solar cells (PSCs) have been measured by different techniques: transient photovoltage decay, transient photoluminescence, and impedance spectroscopy. A slow dynamic process is detected that shows characteristic times in the seconds to milliseconds scale, with good quantitative agreement between transient photovoltage decay and impedance spectroscopy. Here, we show that this characteristic time is related with a novel slow dynamic process caused by the peculiar structural properties of lead halide perovskites and depending on perovskite crystal size and organic cation nature. This new process may lie at the basis of the current-voltage hysteresis reported for PSCs and could have important implications in PSC performance because it may give rise to distinct dynamical behavior with respect to other classes of photovoltaic devices. Furthermore, we show that low-frequency characteristic time, commonly associated with electronic carrier lifetime in other photovoltaic devices, cannot be attributed to a recombination process in the case of PSCs.

  18. 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.

  19. 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.

  20. 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

  1. Interrupted time series analysis of children's blood lead levels: A case study of lead hazard control program in Syracuse, New York.

    Directory of Open Access Journals (Sweden)

    Liyang Shao

    Full Text Available Children's blood lead concentrations have been closely monitored over the last two decades in the United States. The bio-monitoring surveillance data collected in local agencies reflected the local temporal trends of children's blood lead levels (BLLs. However, the analysis and modeling of the long-term time series of BLLs have rarely been reported. We attempted to quantify the long-term trends of children's BLLs in the city of Syracuse, New York and evaluate the impacts of local lead poisoning prevention programs and Lead Hazard Control Program on reducing the children's BLLs. We applied interrupted time series analysis on the monthly time series of BLLs surveillance data and used ARMA (autoregressive and moving average models to measure the average children's blood lead level shift and detect the seasonal pattern change. Our results showed that there were three intervention stages over the past 20 years to reduce children's BLLs in the city of Syracuse, NY. The average of children's BLLs was significantly decreased after the interventions, declining from 8.77μg/dL to 3.94μg/dL during1992 to 2011. The seasonal variation diminished over the past decade, but more short term influences were in the variation. The lead hazard control treatment intervention proved effective in reducing the children's blood lead levels in Syracuse, NY. Also, the reduction of the seasonal variation of children's BLLs reflected the impacts of the local lead-based paint mitigation program. The replacement of window and door was the major cost of lead house abatement. However, soil lead was not considered a major source of lead hazard in our analysis.

  2. Maximization of interventricular conduction time by means of quadripolar leads for cardiac resynchronization therapy.

    Science.gov (United States)

    Stabile, Giuseppe; Bianchi, Valter; Solimene, Francesco; Iuliano, Assunta; Parisi, Quintino; Pepi, Patrizia; Bocchiardo, Mario; Urraro, Francesco; De Simone, Antonio; Ospizio, Roberto; D'Onofrio, Antonio

    2017-10-01

    Identifying the left ventricular (LV) site associated with the maximum spontaneous interventricular conduction time (right ventricle (RV)-to-LV interval) has proved to be an effective strategy for optimal LV pacing site selection in cardiac resynchronization therapy (CRT). The aim of our study was to determine whether quadripolar LV lead technology allows RV-to-LV interval maximization. We enrolled 108 patients undergoing implantation of a CRT system using an LV quadripolar lead and 114 patients who received a bipolar lead. On implantation, the RV-to-LV interval was measured for the dipole of the bipolar leads and for each electrode of the LV lead (tip, ring 2, ring 3, ring 4). In the quadripolar group, the mean RV-to-LV interval ranged from 90 ± 33 ms (tip) to 94 ± 32 ms (R4) (p > 0.05 for all comparisons). In 55 (51%) patients, the RV-to-LV interval was > 80 ms at all electrodes, while in 27 (25%) patients, no electrodes were associated with an RV-to-LV interval > 80 ms. At least one LV pacing electrode was associated with an RV-to-LV interval > 80 ms in 62 (70%) patients with a short (36 mm) inter-electrode distance, and in 19 (95%, p = 0.022) of those with a long distance (50.5 mm). In the bipolar group, the mean RV-to-LV interval was 72 ± 37 ms (p  80 ms in 44 (39%) patients (p leads with both short and long inter-electrode distance). Quadripolar leads allow RV-to-LV interval maximization. An optimal RV-to-LV interval seems achievable in the majority of patients, especially if the leads present a long inter-electrode distance.

  3. A new order splitting model with stochastic lead times for deterioration items

    Science.gov (United States)

    Sazvar, Zeinab; Akbari Jokar, Mohammad Reza; Baboli, Armand

    2014-09-01

    In unreliable supply environments, the strategy of pooling lead time risks by splitting replenishment orders among multiple suppliers simultaneously is an attractive sourcing policy that has captured the attention of academic researchers and corporate managers alike. While various assumptions are considered in the models developed, researchers tend to overlook an important inventory category in order splitting models: deteriorating items. In this paper, we study an order splitting policy for a retailer that sells a deteriorating product. The inventory system is modelled as a continuous review system (s, Q) under stochastic lead time. Demand rate per unit time is assumed to be constant over an infinite planning horizon and shortages are backordered completely. We develop two inventory models. In the first model, it is assumed that all the requirements are supplied by only one source, whereas in the second, two suppliers are available. We use sensitivity analysis to determine the situations in which each sourcing policy is the most economic. We then study a real case from the European pharmaceutical industry to demonstrate the applicability and effectiveness of the proposed models. Finally, more promising directions are suggested for future research.

  4. The lead time tradeoff: the case of health states better than dead.

    Science.gov (United States)

    Pinto-Prades, José Luis; Rodríguez-Míguez, Eva

    2015-04-01

    Lead time tradeoff (L-TTO) is a variant of the time tradeoff (TTO). L-TTO introduces a lead period in full health before illness onset, avoiding the need to use 2 different procedures for states better and worse than dead. To estimate utilities, additive separability is assumed. We tested to what extent violations of this assumption can bias utilities estimated with L-TTO. A sample of 500 members of the Spanish general population evaluated 24 health states, using face-to-face interviews. A total of 188 subjects were interviewed with L-TTO and the rest with TTO. Both samples evaluated the same set of 24 health states, divided into 4 groups with 6 health states per set. Each subject evaluated 1 of the sets. A random effects regression model was fitted to our data. Only health states better than dead were included in the regression since it is in this subset where additive separability can be tested clearly. Utilities were higher in L-TTO in relation to TTO (on average L-TTO adds about 0.2 points to the utility of health states), suggesting that additive separability is violated. The difference between methods increased with the severity of the health state. Thus, L-TTO adds about 0.14 points to the average utility of the less severe states, 0.23 to the intermediate states, and 0.28 points to the more severe estates. L-TTO produced higher utilities than TTO. Health problems are perceived as less severe if a lead period in full health is added upfront, implying that there are interactions between disjointed time periods. The advantages of this method have to be compared with the cost of modeling the interaction between periods. © The Author(s) 2014.

  5. Pathway from central obesity to childhood asthma. Physical fitness and sedentary time are leading factors.

    Science.gov (United States)

    Chen, Yang-Ching; Tu, Yu-Kang; Huang, Kuo-Chin; Chen, Pau-Chung; Chu, Da-Chen; Lee, Yungling Leo

    2014-05-15

    Available prospective studies of obesity and asthma have used only body mass index (BMI) as an indicator for adiposity; studies using detailed obesity measures are lacking, and the role of physical fitness level and sedentary time remains unexplored in the link between obesity and asthma. To compare various anthropometric measures of obesity in relation to childhood asthma, and to further characterize the interrelations among central obesity, physical fitness level, sedentary time, and asthma. The nationwide Taiwan Children Health Study followed 2,758 schoolchildren from fourth to sixth grade, annually collecting data regarding physical fitness, sedentary time, obesity measures (comprising body weight and height, abdominal and hip circumference, skin fold thickness, and body composition), asthma, and pulmonary function tests. The generalized estimating equation was used for 3 years of repeated measurements to analyze the interrelation among obesity, sedentary time, physical fitness level, and asthma; a structural equation model was used to explore the pathogenesis among these factors. Asthma incidence was analyzed during a 2-year follow-up among centrally obese and nonobese groups in baseline children without asthma. Central obesity most accurately predicts asthma. Low physical fitness levels and high screen time increase the risk of central obesity, which leads to asthma development. Obesity-related reduction in pulmonary function is a possible mechanism in the pathway from central obesity to asthma. Central obesity measures should be incorporated in childhood asthma risk predictions. Children are encouraged to increase their physical fitness levels and reduce their sedentary time to prevent central obesity-related asthma.

  6. Assessment of circuit board surface finishes for electronic assembly with lead-free solders

    Energy Technology Data Exchange (ETDEWEB)

    Ray, U.; Artaki, I.; Finley, D.W.; Wenger, G.M. [Bell Labs., Princeton, NJ (United States). Lucent Technologies; Pan, T.; Blair, H.D.; Nicholson, J.M. [Ford Motor Co., Dearborn, MI (United States); Vianco, P.T. [Sandia National Labs., Albuquerque, NM (United States)

    1996-10-01

    The suitability of various metallic printed wiring board surface finishes was assessed for new technology applications that incorporate assembly with Lead-free solders. The manufacture of a lead-free product necessitates elimination of lead (Pb) from the solder, the circuit board as well as the component lead termination. It is critical however for the selected interconnect Pb-free solder and the corresponding printed wiring board (PWB) and component lead finishes to be mutually compatible. Baseline compatibility of select Pb-free solders with Pb containing PWB surface finish and components was assessed. This was followed by examining the compatibility of the commercially available CASTIN{trademark} (SnAgCuSb) Pb-free solder with a series of PWB metallic finishes: Ni/Au, Ni/Pd, and Pd/Cu. The compatibility was assessed with respect to assembly performance, solder joint integrity and long term attachment reliability. Solder joint integrity and mechanical behavior of representative 50 mil pitch 20I/O SOICs was determined before and after thermal stress. Mechanical pull test studies demonstrated that the strength of SnAgCuSb solder interconnections is notably greater than that of SnPb interconnections.

  7. Pancreatectomy Versus Conservative Management for Pancreatic Cancer: A Question of Lead-time Bias.

    Science.gov (United States)

    Kendal, Wayne S

    2015-10-01

    Pancreatectomy is regarded as the only curative treatment for cancer of the pancreas. A population-based study was conducted to examine its efficacy within the general community. Overall and cancer-specific survivals were compared between individuals treated with pancreatectomy and those managed nonsurgically. Kaplan-Meier analysis was used, based on both time from diagnosis and attained age (age at diagnosis plus time from diagnosis). A total of 7830 Surveillance Epidemiology and End Results cases of localized cancer of the pancreatic head were retrieved, diagnosed from 2000 to 2008. Median follow-up was 12 months; the pancreatectomy cohort was 5 years younger and had 7-fold less stage III disease. Overall and cancer-specific survivals were 17% and 21% at 5 years from time of diagnosis in the pancreatectomy cohort versus 2% and 4% in the nonsurgical cohort, respectively (Ppancreatectomy cohort was diagnosed earlier, with less disease. If most of these individuals had occult metastases at diagnosis, which manifested later and caused death at similar ages as the nonsurgical cohort, their survival from time of diagnosis would appear speciously improved. A randomized controlled trial would be necessary to confirm whether or not the survival advantage ascribed to pancreatectomy should be attributed to lead-time bias.

  8. 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…

  9. 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, ...

  10. New real-time heartbeat detection method using the angle of a single-lead electrocardiogram.

    Science.gov (United States)

    Song, Mi-Hye; Cho, Sung-Pil; Kim, Wonky; Lee, Kyoung-Joung

    2015-04-01

    This study presents a new real-time heartbeat detection algorithm using the geometric angle between two consecutive samples of single-lead electrocardiogram (ECG) signals. The angle was adopted as a new index representing the slope of ECG signal. The method consists of three steps: elimination of high-frequency noise, calculation of the angle of ECG signal, and detection of R-waves using a simple adaptive thresholding technique. The MIT-BIH arrhythmia database, QT database, European ST-T database, T-wave alternans database and synthesized ECG signals were used to evaluate the performance of the proposed algorithm and compare with the results of other methods suggested in literature. The proposed method shows a high detection rate-99.95% of the sensitivity, 99.95% of the positive predictivity, and 0.10% of the fail detection rate on the four databases. The result shows that the proposed method can yield better or comparable performance than other literature despite the relatively simple process. The proposed algorithm needs only a single-lead ECG, and involves a simple and quick calculation. Moreover, it does not require post-processing to enhance the detection. Thus, it can be effectively applied to various real-time healthcare and medical devices. Copyright © 2015 Elsevier Ltd. All rights reserved.

  11. Assessment of pollution aerosols sources above the Straits of Dover using lead isotope geochemistry

    Energy Technology Data Exchange (ETDEWEB)

    Deboudt, K.; Flament, P. [Universite du Littoral-Cote d' Opale, LISE-ELICO UPRES-A CNRS 8013, BP 59, F-62930 Wimereux (France); Weis, D.; Mennessier, J.P. [Universite Libre de Bruxelles, Departement Sciences de la Terre et de l' Environnement, CP 160/02, B-1050 Brussels (Belgium); Maquinghen, P. [Universite du Littoral-Cote d' Opale, LISE-ELICO (UPRES-A CNRS 8013), BP 59, F-62930 Wimereux (France)

    1999-09-15

    We assess the capability of lead isotopes to study the transport of pollution aerosols above the Straits of Dover by collecting atmospheric aerosols above the Eastern Channel and the Southern Bight of the North Sea. During the same period, we characterized the lead isotopic signature of the main industrial sources on the French coast near the Straits of Dover. Urban and automobile-derived aerosols were also collected. Due to the phasing out of lead in gasoline, the urban isotopic composition (206Pb/207Pb=1.158{+-}0.003) has become more radiogenic, although it is highly variable. On a regional scale, major industrial emissions have a well-defined isotopic composition (1.13<206Pb/207Pb<1.22), more radiogenic than the petrol-lead signature (1.06<206Pb/207Pb<1.12). These results together with those measured near the main coastal highway show that the automobile source has become a minor component of particulate lead in air. On a local scale, Dunkerque, the most urbanized and industrialized area along the Straits of Dover, may transiently control elevated lead concentrations. Except for the occurrence of local and regional range transport episodes, lead concentrations in the Straits of Dover can be related to remote or semi-remote pollution source emissions. Combining air mass retrospective trajectories and related lead abundances and isotopic compositions, it can be shown that lead aerosols originating from eastern Europe have an isotopic signature (1.145<206Pb/207Pb<1.169) different from the isotopic composition of west-European lead aerosols (1.111<206Pb/207Pb<1.142). The influence of remote North American sources is suggested, with caution, due to uncertainties in meteorological calculations.

  12. Assessing the sources and bioaccessibility of Lead in Soils from London

    Science.gov (United States)

    Cave, Mark R.; Wragg, Joanna; Chenery, Simon

    2013-04-01

    The lead content of soil is important since it is toxic to humans and particularly because children tend to more readily absorb lead than do adults: children absorb up to 40% into the bloodstream from ingested or inhaled lead, versus 5-15% in adults. Studies have shown that relatively low concentrations of lead in blood can lead to significant decrease in IQ of children (e.g. Jakubowski, 2011) leading to neuropathy and hypertension in adults. The British Geological Survey has recently completed a systematic high-density geochemical soil survey of the Greater London Area (GLA) in which over 6000 surface soil samples were collected and analysed for 50 elements. The Pb content of the soils range from 11 mg/kg to greater than 10000 mg/kg with mean and median values of 301 and 185 mg/kg, respectively. The ingestion bioaccessible fraction of Pb was measured using an in-vitro bioaccessibility test showing that 68% of the total Pb in London soils is bioaccessible. Measurement of Pb isotopic ratios in selected soils matched with those found in London air particulates and, to a lesser extent, with petrol lead. Self modelling mixture resolution of the 50 element geochemical data set was used to identify geochemically distinct components in the data with Pb being associated with 11 of the components which were of both natural and anthropogenic origin. Relationships between the soil components, the bioaccessible fraction and the Pb isotope ratios provided an indication of the sources of mobile lead in the London soils. References JAKUBOWSKI, M. 2011. Low-level environmental lead exposure and intellectual impairment in children - the current concepts of risk assessment. International Journal of Occupational Medicine and Environmental Health, Vol. 24, 1-7. APPLETON, J D, CAVE, M R, and WRAGG, J. 2012. Modelling lead bioaccessibility in urban topsoils based on data from Glasgow, London, Northampton and Swansea, UK. Environmental Pollution, Vol. 171, 265-272.

  13. Lead Paint Exposure Assessment in High Bays of Johnson Space Center

    Science.gov (United States)

    Stanch, Penney; Plaza, Angel; Keprta, Sean

    2008-01-01

    This slide presentation reviews the program to assess the possibility of lead paint exposure in the high bays of some of the Johnson Space Center buildings. Some of the buildings in the Manned Space Flight Center (MSC) were built in 1962 and predate any considerations to reduce lead in paints and coatings. There are many of these older buildings that contain open shops and work areas that have open ceilings, These shops include those that had operations that use leaded gasoline, batteries, and lead based paints. Test were planned to be conducted in three phases: (1) Surface Dust sampling, (2) personal exposure montioring, and (3) Ceiling paint Sampling. The results of the first two phases were reviewed. After considering the results of the first two phases, and the problems associated with the retrieval of samples from high ceilings, it was determined that the evaluation of ceiling coatings would be done on a project by project and in response to a complaint.

  14. Assessing urbanization impacts on catchment transit times

    National Research Council Canada - National Science Library

    Soulsby, Chris; Birkel, Christian; Tetzlaff, Doerthe

    2014-01-01

    .... Percent urban cover influenced the shape of the catchment transit time distribution. Total urban cover reduced the mean transit time to <10 days compared with ~1 year and ~2–3 years with 63% and 13...

  15. Dahl: Time ripe for DHS net assessment

    OpenAIRE

    2016-01-01

    Article review Center for Homeland Defense and Security instructor Erik Dahl urges the Department of Homeland Security to follow a practice of its military counterparts and establish an Office of Net Assessment that would gauge future threats and the nation's ability to mitigate them.

  16. Time Domain Stability Margin Assessment Method

    Science.gov (United States)

    Clements, Keith

    2017-01-01

    The baseline stability margins for NASA's Space Launch System (SLS) launch vehicle were generated via the classical approach of linearizing the system equations of motion and determining the gain and phase margins from the resulting frequency domain model. To improve the fidelity of the classical methods, the linear frequency domain approach can be extended by replacing static, memoryless nonlinearities with describing functions. This technique, however, does not address the time varying nature of the dynamics of a launch vehicle in flight. An alternative technique for the evaluation of the stability of the nonlinear launch vehicle dynamics along its trajectory is to incrementally adjust the gain and/or time delay in the time domain simulation until the system exhibits unstable behavior. This technique has the added benefit of providing a direct comparison between the time domain and frequency domain tools in support of simulation validation.

  17. Improving DLA Supply Chain Agility: Lead Times, Order Quantities, and Information Flow

    Science.gov (United States)

    2015-01-01

    iq u e N IIN s 90 80 70 60 50 40 30 20 10 100 0 En gi ne ac ce sso rie s Be ar in gs Ele ctr ic wi re , p ow er d ist rib ut io n eq ui...delivery quantity vs . order quantity k. Inclusion of lead times in contracts 4. Process for evaluating supplier performance (metrics, which suppliers...Distributions RAND RR822-D.13 Fr eq u en cy 400 300 200 100 500 0 1.4 5 1.4 0 1.3 5 1.3 0 1.2 5 1.2 0 1.1 5 1.1 0

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

    OpenAIRE

    Johansen, Søren Glud; Thorstenson, Anders

    2006-01-01

    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 for optimality are exact.

  20. 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.

  1. 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.

  2. Modelagem matemática do efeito chicote em ambientes com demanda e lead time estocásticos

    Directory of Open Access Journals (Sweden)

    José Carlos Fioriolli

    2009-04-01

    Full Text Available O aumento da variabilidade da demanda ao longo de uma cadeia de abastecimento é conhecido como Efeito Chicote (EC. A modelagem deste fenômeno é fundamental para a quantificação de sua intensidade, ajudando a reduzir seus impactos negativos sobre o nível de serviço e sobre os estoques em cadeias de abastecimento. Este artigo apresenta uma proposta de modelagem do EC que tem por objetivo aumentar a precisão na quantificação deste fenômeno em ambientes com demanda e lead time estocásticos. O novo modelo considera um elemento que não está presente nos principais modelos disponíveis na literatura: a variabilidade no lead time de entrega de pedidos. Além disso, define de modo mais preciso o papel do coeficiente de variação da demanda na quantificação do EC. A utilização do modelo proposto aumenta a eficiência da gestão de cadeias de abastecimento ao contribuir para atenuar a propagação do EC.The increase in demand variability as information flows from customers to manufacturers in a supply chain is known as the Bullwhip Effect (BE. Modeling this phenomenon is key in measuring its intensity, aiming at reducing its negative impact on both service and inventory levels in supply chains. This paper proposes a new, more precise mathematical model for quantifying the BE in systems with stochastic demand and lead time. The new model takes into account the lead time variability, an element not present in the BE literature. In addition, the model allows a more precise assessment of the role that the demand's coefficient of variation plays when quantifying the BE. The use of the proposed model enables an improved management of the supply chain by attenuating the propagation of the BE.

  3. An exposure and health risk assessment of lead (Pb) in lipstick.

    Science.gov (United States)

    Monnot, Andrew D; Christian, Whitney V; Abramson, Matthew M; Follansbee, Mark H

    2015-06-01

    Lead (Pb) content in lipstick and other consumer products has become an increasing concern. In 2010, the United States Food and Drug Administration tested 400 lipstick samples and found a maximum Pb concentration of 7.19 ppm. To assess the safety of lipstick in adults that chronically apply lipstick as well as instances where children might incidentally ingest lipstick products, the United States Environmental Protection Agency's (US EPA) Adult Lead Model and Integrated Exposure Uptake Biokinetic Model for Lead in Children were used to determine the blood Pb concentrations of adults and children ingesting varying amounts of lipstick of different Pb concentrations. Modeled blood Pb concentrations were compared with oral ingestion guidelines and to the Centers for Disease Control and the US EPA's actionable blood Pb levels of 5 and 10 µg/dL. Background Pb exposure was the primary contributor to estimated blood Pb levels (BLLs) in children and adults, and Pb exposure from lipstick did not significantly increase estimated BLLs. These results suggest that the safety of consumer products and cosmetics should be assessed not only by the presence and amounts of hazardous contents, but also in conjunction with an assessment of estimated background exposures and comparison to health-based standards. Copyright © 2015 Elsevier Ltd. All rights reserved.

  4. Proper Assessment of the JFK Assassination Bullet Lead Evidence from Metallurgical and Statistical Perspectives

    Energy Technology Data Exchange (ETDEWEB)

    Randich, E; Grant, P M

    2006-08-29

    The bullet evidence in the JFK assassination investigation was reexamined from metallurgical and statistical standpoints. The questioned specimens are comprised of soft lead, possibly from full-metal-jacketed Mannlicher-Carcano, 6.5-mm ammunition. During lead refining, contaminant elements are removed to specified levels for a desired alloy or composition. Microsegregation of trace and minor elements during lead casting and processing can account for the experimental variabilities measured in various evidentiary and comparison samples by laboratory analysts. Thus, elevated concentrations of antimony and copper at crystallographic grain boundaries, the widely varying sizes of grains in Mannlicher-Carcano bullet lead, and the 5-60 mg bullet samples analyzed for assassination intelligence effectively resulted in operational sampling error for the analyses. This deficiency was not considered in the original data interpretation and resulted in an invalid conclusion in favor of the single-bullet theory of the assassination. Alternate statistical calculations, based on the historic analytical data, incorporating weighted averaging and propagation of experimental uncertainties also considerably weaken support for the single-bullet theory. In effect, this assessment of the material composition of the lead specimens from the assassination concludes that the extant evidence is consistent with any number between two and five rounds fired in Dealey Plaza during the shooting.

  5. Proper assessment of the JFK assassination bullet lead evidence from metallurgical and statistical perspectives.

    Science.gov (United States)

    Randich, Erik; Grant, Patrick M

    2006-07-01

    The bullet evidence in the JFK assassination investigation was reexamined from metallurgical and statistical standpoints. The questioned specimens are comprised of soft lead, possibly from full-metal-jacketed Mannlicher-Carcano (MC), 6.5-mm ammunition. During lead refining, contaminant elements are removed to specified levels for a desired alloy or composition. Microsegregation of trace and minor elements during lead casting and processing can account for the experimental variabilities measured in various evidentiary and comparison samples by laboratory analysts. Thus, elevated concentrations of antimony and copper at crystallographic grain boundaries, the widely varying sizes of grains in MC bullet lead, and the 5-60 mg bullet samples analyzed for assassination intelligence effectively resulted in operational sampling error for the analyses. This deficiency was not considered in the original data interpretation and resulted in an invalid conclusion in favor of the single-bullet theory of the assassination. Alternate statistical calculations, based on the historic analytical data, incorporating weighted averaging and propagation of experimental uncertainties also considerably weaken support for the single-bullet theory. In effect, this assessment of the material composition of the lead specimens from the assassination concludes that the extant evidence is consistent with any number between two and five rounds fired in Dealey Plaza during the shooting.

  6. 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

  7. 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

  8. Assessment of cadmium and lead adsorption in organic and conventional coffee.

    Science.gov (United States)

    Marchioni, Camila; de Oliveira, Fagner Moreira; de Magalhães, Cristiana Schmidt; Luccas, Pedro Orival

    2015-01-01

    Many metals are toxic in human organism, as is the case of cadmium and lead. Therefore, the metal levels in food need to be controlled. In coffee, metals may present risks when they are extracted from the powder to be consumed as beverage. A flow injection analysis (FIA) system is proposed, with atomic absorption detection, to metal adsorption studies in coffee powder. Kinetic study, best isotherms and time, and mass influences were determined. They allowed analyzing the high lead and cadmium adsorption percentage in organic and conventional ground coffee. Metal adsorption occurs in multilayers, following Freundlich's model, and the kinetic model obeyed is the pseudo-second order. The cadmium adsorption suffered higher temperature influence, while the lead retention suffered higher mass influence. This study indicates that the majority of these toxic agents will be retained in the powder and will not be consumed by man, avoiding possible deleterious effects.

  9. Lead Exposure Assessment among Pregnant Women, Newborns, and Children: Case Study from Karachi, Pakistan.

    Science.gov (United States)

    Fatmi, Zafar; Sahito, Ambreen; Ikegami, Akihiko; Mizuno, Atsuko; Cui, Xiaoyi; Mise, Nathan; Takagi, Mai; Kobayashi, Yayoi; Kayama, Fujio

    2017-04-13

    Lead (Pb) in petrol has been banned in developed countries. Despite the control of Pb in petrol since 2001, high levels were reported in the blood of pregnant women and children in Pakistan. However, the identification of sources of Pb has been elusive due to its pervasiveness. In this study, we assessed the lead intake of pregnant women and one- to three-year-old children from food, water, house dust, respirable dust, and soil. In addition, we completed the fingerprinting of the Pb isotopic ratios (LIR) of petrol and secondary sources (food, house-dust, respirable dust, soil, surma (eye cosmetics)) of exposure within the blood of pregnant women, newborns, and children. Eight families, with high (~50 μg/dL), medium (~20 μg/dL), and low blood levels (~10 μg/dL), were selected from 60 families. The main sources of exposure to lead for children were food and house-dust, and those for pregnant women were soil, respirable dust, and food. LIR was determined by inductively coupled plasma quadrupole mass spectrometry (ICP-QMS) with a two sigma uncertainty of ±0.03%. The LIR of mothers and newborns was similar. In contrast, surma , and to a larger extent petrol, exhibited a negligible contribution to both the child's and mother's blood Pb. Household wet-mopping could be effective in reducing Pb exposure. This intake assessment could be replicated for other developing countries to identify sources of lead and the burden of lead exposure in the population.

  10. Time trend and determinants of blood lead levels in a Swiss population over a transition period (1984-1993) from leaded to unleaded gasoline use

    Energy Technology Data Exchange (ETDEWEB)

    Wietlisbach, V.; Rickenbach, M. [Institute universitaire de medecine Sociale et preventive, Lausanne (Switzerland); Berode, M. [Institut universitaire Romand de la sante au travail, Lausanne (Switzerland)] [and others

    1995-02-01

    This study analyzes the trend and determinants of blood lead levels in a Swiss region (population 770,000) over the 10-year period following the introduction of unleaded gasoline in 1985. The consumption of unleaded fuel increased rapidly, accounting in 1988 for 36% and in 1992 for 65% of all gasoline sales. Blood lead levels were measured in three representative samples (n = 1700) of the adult population within the framework of a health examination survey carried out in 1984/1985, 1988/1989, and 1992/1993. The geometric mean blood lead levels were, respectively, 0.59, 0.42, and 0.33 {mu}mole/liter in men, 0.41, 0.29, and 0.25 {mu}mole/liter in women. Similar trends have been observed across all age groups, occupational classes, and categories across all age groups, occupational classes, and categories based on smoking, drinking, and dietary habits. The overexposure of city residents, in comparison to village residents, fades out over the observation period. These findings suggest that the changeover from leaded to unleaded gasoline has been the major cause of the blood lead decline. Wine drinking, cigarette smoking, and age appear to be significant determinants of blood lead for both sexes in all three surveys. In contrast, the association is inverse for milk consumption. The multivariate regression analysis shows that wine drinking remains the most important predictor of blood lead, whereas the influence of age increases with time and overcomes the effect of smoking in the third survey. 32 refs., 21 refs., 6 tabs.

  11. Time-Spectral Analysis Methods for Spent Fuel Assay Using Lead Slowing-Down Spectroscopy

    Science.gov (United States)

    Smith, L. Eric; Anderson, Kevin K.; Ressler, Jennifer J.; Shaver, Mark W.

    2010-08-01

    Nondestructive techniques for measuring the mass of fissile isotopes in spent nuclear fuel is a considerable challenge in the safeguarding of nuclear fuel cycles. A nondestructive assay technology that could provide direct measurement of fissile mass, particularly for the plutonium (Pu) isotopes, and improve upon the uncertainty of today's confirmatory methods is needed. Lead slowing-down spectroscopy (LSDS) has been studied for the spent fuel application previously, but the nonlinear effects of assembly self shielding (of the interrogating neutron population) have led to discouraging assay accuracy for realistic pressurized water reactor fuels. In this paper, we describe the development of time-spectral analysis algorithms for LSDS intended to overcome these self-shielding effects. The algorithm incorporates the tabulated energy-dependent cross sections from key fissile and absorbing isotopes, but leaves their mass as free variables. Multi-parameter regression analysis is then used to directly calculate not only the mass of fissile isotopes in the fuel assembly (e.g., Pu-239, U-235, and Pu-241), but also the mass of key absorbing isotopes such as Pu-240 and U-238. Modeling-based assay results using this self-shielding relationship indicate that LSDS has the potential to directly measure fissile isotopes with less than 5% average relative error for pressurized water reactor assemblies with burnup as high as 60 GWd/MTU. Shortcomings in the initial self-shielding model and potential improvements to the formulation are described.

  12. Normalizing considerations for time to stabilization assessment.

    Science.gov (United States)

    Gribble, Phillip A; Mitterholzer, Jessica; Myers, Alyse N

    2012-03-01

    Because of the growing use of time to stabilization (TTS) and similar measures with single-limb landings in lower extremity research, it is important to determine if the task performance needs to be normalized further. The purpose of this study was to compare TTS of healthy participants using a standardized versus a normalized horizontal jumping distance. Crossover study. Twenty-one healthy participants performed single landings using two horizontal jumping distances: standardized (70 cm) and normalized (leg length). Resultant vector TTS (RVTTS) was calculated to represent the dynamic stability performance. For RVTTS, the participants took significantly longer to stabilize when using the normalized jumping distance (1.997±0.181 s) compared with the standardized jumping distance (1.921±0.126 s) (t=5.134; pnormalized jumping distance was more strongly correlated with leg length (r=0.628; p=0.002) than during the standardized jumping distance (r=0.563; p=0.008). Normalizing the horizontal jumping distance during the single-limb jumping task creates a performance decrement in RVTTS among healthy participants. Because dynamic stability measured with RVTTS when jumping a normalized distance is more strongly correlated with leg length than when jumping a standardized jumping distance, researchers using this task and analysis may want to consider using this additional normalizing step in future investigations. Copyright © 2011. Published by Elsevier Ltd.

  13. Assessment of the efficacy of chelate-assisted phytoextraction of lead by coffeeweed (Sesbania exaltata Raf.).

    Science.gov (United States)

    Miller, Gloria; Begonia, Gregorio; Begonia, Maria; Ntoni, Jennifer; Hundley, Oscar

    2008-12-01

    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 mum 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 with the metal) or

  14. 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

  15. BACKORDER AND LOST SALES CONTINUOUS REVIEW RAW MATERIAL INVENTORY CONTROL SYSTEM WITH LEAD TIME AND ORDERING COST REDUCTION

    Directory of Open Access Journals (Sweden)

    Tiena Gustina Amran

    2012-06-01

    Full Text Available The purpose of this research is to suggest the optimal raw material inventory system alternatives synchronized with the stock out characteristics and the condition can be occurred, the backorder raw material inventory control, beside that it also can reduce lead time and raw material ordering cost. In this case, the inventory models also extent (Q, R Inventory Model Under lead Time and Ordering Cost Reduction with lead time and ordering cost can be reduced. After the calculation, the optimal solution of inventory models can be obtained; those are with backorder condition which produced the annual inventory total cost for the company.

  16. Blood lead levels and δ-ALAD inhibition in nestlings of Eurasian Eagle Owl (Bubo bubo) to assess lead exposure associated to an abandoned mining area.

    Science.gov (United States)

    Gómez-Ramírez, P; Martínez-López, E; María-Mojica, P; León-Ortega, M; García-Fernández, A J

    2011-01-01

    In order to biomonitor lead contamination in Southeastern Spain, 218 blood samples from 28 to 30-day old Eurasian Eagle Owl chicks (Bubo bubo) born between 2003 and 2007 were analysed. In general, mean lead levels showed that chicks were exposed to background concentrations. However, mean levels in chicks born in an ancient and abandoned mining site ("Sierra Minera Cartagena-La Union") or in their surroundings (Geometric mean (GM) = 5.83 μg/dl, range 0.49-25.61 μg/dl), an area highly polluted by lead and other metals, were significantly higher (p ALAD activity is considered the best biomarker for lead exposure and effect in birds, the activity of this enzyme was also evaluated and correlated with lead levels in blood. In this study, low levels of blood lead inhibited δ-ALAD, even when lead concentrations were lower than the limits described by other authors in raptors. Adverse effects caused by this inhibition may occur when blood lead levels were above 15 μg/dl, although only eight chicks presented these concentrations in their blood. Sampling site also influenced enzymatic activity, since it decreased about 60% in the polluted area in relation to the rest. For all these reasons, further research regarding risk assessment for lead exposure in Eagle Owls nesting in the polluted area is advisable. Our results suggest that the Eurasian Eagle Owl can be considered a suitable sentinel animal for monitoring lead contamination and δ-ALAD activity can be used as a sensitive biomarker for lead exposure and effect in this species.

  17. 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.

  18. 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.

  19. Increasing streamflow forecast lead time for snowmelt-driven catchment based on large-scale climate patterns

    Science.gov (United States)

    Kalra, Ajay; Ahmad, Sajjad; Nayak, Anurag

    2013-03-01

    This study focuses on improving the spring-summer streamflow forecast lead time using large scale climate patterns. An artificial intelligence type data-driven model, Support Vector Machine (SVM), was developed incorporating oceanic-atmospheric oscillations to increase the forecast lead time. The application of SVM model is tested on three unimpaired gages in the North Platte River Basin. Seasonal averages of oceanic-atmospheric indices for the period of 1940-2007 are used to generate spring-summer streamflow volumes with 3-, 6- and 9-month lead times. The results reveal a strong association between coupled indices compared to their individual effects. The best streamflow estimates are obtained at 6-month compared to 3-month and 9-month lead times. The proposed modeling technique is expected to provide useful information to water managers and help in better managing the water resources and the operation of water systems.

  20. 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)

  1. Effects of meals and meal times on uptake of lead from the gastrointestinal tract in humans.

    Science.gov (United States)

    James, H M; Hilburn, M E; Blair, J A

    1985-07-01

    Twenty three adults ingested 203Pb as lead acetate on the 12th hour of a 19 h fast. Retention measured 7 days later in a whole-body counter was 61% and whole-body turnover rates suggested that initial uptake had been considerably greater. Balanced meals eaten with 203Pb reduced lead uptake to 4% and the influence of the food lasted for up to 3 h. The effects of phytate, ethylene-diaminetetra acetate (EDTA), caffeine, alcohol, glucose, a liquid meal and a light snack were tested separately with intermediate results. The effect of a meal was probably largely due to its content of calcium and phosphate salts but lead uptake was probably further reduced by phytate which is plentiful in whole cereals and it was probably increased by a factor in milk. Uptake with skimmed milk was the same as with whole milk and we suggested that the factor was not fat. Comestibles with low mineral and phytate contents reduced lead uptake by intermediate amounts, possibly by stimulation of digestive secretions. The avid uptake of lead during a fast, the large reduction of lead uptake with meals and the likelihood of variations in gastric-emptying rates and dietary habits may be major causes of variation in body burdens of lead in the population.

  2. 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.

  3. 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...

  4. 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…

  5. Assessing Local Turbulence Strength from a Time Series

    Directory of Open Access Journals (Sweden)

    Mayer Humi

    2010-01-01

    Full Text Available We study the possible link between “local turbulence strength” in a flow which is represented by a finite time series and a “chaotic invariant”, namely, the leading Lyaponuv exponent that characterizes this series. To validate a conjecture about this link, we analyze several time series of measurements taken by a plane flying at constant height in the upper troposphere. For each of these time series we estimate the leading Lyaponuv exponent which we then correlate with the structure constants for the temperature. In addition, we introduce a quantitative technique to educe the scale contents of the flow and a methodology to validate its spectrum.

  6. French external quality assessment schemes for lead in blood and aluminum in plasma and dialysis water.

    Science.gov (United States)

    Guillard, O; Piriou, A; Pineau, A

    1996-01-01

    An external quality assessment scheme (EQAS) for lead in blood was established in France in 1992 at the request of the Ministry of Labour and organised by the Drug Bureau. Participation is mandatory for laboratories wishing to obtain ministerial approval for the determination of blood lead levels. In 1994, two interlaboratory comparative exercises were carried out, each involving the analysis of 3 samples of human blood (2 with and 1 without lead supplementation). Out of 66 enrolled laboratories, 58 and 60 participated in the two exercises, respectively. The scattering of results was quite comparable to that observed in other EQAS. The EQAS for plasma aluminium was established in 1983 at the request of the Commission on Trace Elements of the Société Française de Biologie Clinique. Today, 80 laboratories in 22 countries on 4 continents participate in this scheme. Six exercises are carried out each year, each including 3 plasma samples (2 with and 1 without aluminium supplementation), 2 samples of water supplemented with aluminium and a blank (water). The results obtained in this scheme showed an improvement in the quality of the analyses.

  7. DECA: a new model for assessing the foliar uptake of atmospheric lead by vegetation, using Lactuca sativa as an example.

    Science.gov (United States)

    Schreck, E; Bonnard, R; Laplanche, C; Leveque, T; Foucault, Y; Dumat, C

    2012-12-15

    In the context of peri-urban atmospheric pollution by industrial lead recycling emissions, metal can transfer to plant shoots. Home gardeners consuming their produce can therefore be exposed to metal pollution. The Human Health Risk Assessment Protocol (HHRAP) model from the United States Environmental Protection Agency (US EPA) classically used in risk assessment provides foliar metal uptake predictions for large farms but is not adapted to cultures in kitchen gardens. Thus, this study developed a new model, entitled "DECA", which includes individually measured parameters and the washing of vegetables before human consumption. Results given by DECA and HHRAP models were compared with experimental measurements of lettuce. The data calculated by the DECA model were highly correlated with the measured values; the HHRAP model overestimates foliar lead uptake. Moreover, strong influences of factor of washing and time-dependent variations of loss coefficient were highlighted. Finally, the DECA model provided important risk assessment data regarding consumption of vegetables from kitchen gardens. Copyright © 2012 Elsevier Ltd. All rights reserved.

  8. Introducing an Instrument to Assess Time Orientation and Time Relation in Adolescents

    Science.gov (United States)

    Mello, Zena R.; Finan, Laura J.; Worrell, Frank C.

    2013-01-01

    We report on two studies that examine new instruments that assess time orientation and time relation in adolescents. These concepts refer to how individuals think about the past, the present, and the future, with time orientation defined as the emphasis one gives toward each time period and time relation defined as the degree one perceives that…

  9. Time series modeling of system self-assessment of survival

    Energy Technology Data Exchange (ETDEWEB)

    Lu, H.; Kolarik, W.J. [Texas Tech Univ., Lubbock, TX (United States). Dept. of Industrial Engineering

    1999-06-01

    Self-assessment of survival for a system, subsystem or component is implemented by assessing conditional performance reliability in real-time, which includes modeling and analysis of physical performance data. This paper proposes a time series analysis approach to system self-assessment (prediction) of survival. In the approach, physical performance data are modeled in a time series. The performance forecast is based on the model developed and is converted to the reliability of system survival. In contrast to a standard regression model, a time series model, using on-line data, is suitable for the real-time performance prediction. This paper illustrates an example of time series modeling and survival assessment, regarding an excessive tool edge wear failure mode for a twist drill operation.

  10. Assessment of TiO2 photoactivity on the lead removal: kinetic and mechanistic processing.

    Science.gov (United States)

    Peter, Anca; Mihaly-Cozmuta, Anca; Nicula, Camelia; Mihaly-Cozmuta, Leonard

    2017-06-01

    Removal of lead ions from aqueous solutions, in the presence and in absence of commercial TiO2, under UV-light was studied. The influence of catalyst mass, concentration of Pb(II) ions and of citric acid in the starting solution as well as the impact of illumination conditions on the removal rate were also investigated. The results were fitted on the pseudo-first order, pseudo-second order and Elovich kinetic models, Weber-Morris intraparticle and liquid film diffusion models, in order to establish the photoreduction mechanism. The Pb removal rate increased in time by a combined linear-exponential mechanism. The catalyst had a positive influence on the removal rate at the start of the photoreduction. At a low concentration of Pb(II) ions (20 mg/L), the amount of photoreduced Pb(II) ions was proportional to the concentration of the citric acid solution, but at high concentrations (240 mg/L), the correlation was inversely proportional. The rate limiting steps in the removal of lead were both the photoreduction on the TiO2 surface and the diffusion through the film surrounding the catalyst particle. The lead removal was significantly influenced by the mobility and by the concentration of the species in solution.

  11. 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.

  12. 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.

  13. Lead time for medium range prediction of the dry spell of monsoon ...

    Indian Academy of Sciences (India)

    The mon- soon applications for numerical weather predic- tion were recently addressed by Krishnamurti et al. (2009), who noted medium range forecast improve- ments of precipitation for timescale of roughly five days. These promising studies lead us to ask for more specific phenomenological applications for the monsoon ...

  14. 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…

  15. Lead-based paint health risk assessment in dependent children living in military housing.

    Science.gov (United States)

    Stroop, Davis M.; Dietrich, Kim N.; Hunt, Allen N.; Suddendorf, Lawrence R.; Giangiacomo, Mark

    2002-01-01

    OBJECTIVE: In children, lead can cause serious permanent damage as a neurotoxicant. The objectives of the study were to evaluate potential exposure to lead-based paint in family housing units at a typical U.S. military installation and determine blood lead (PbB) levels in children ages 6 years or younger residing in these housing units. METHODS: The authors conducted a risk assessment of 1,723 housing units and occupants at Fort Devens in Massachusetts. Data from the military dependent cohort was compared to estimates for the U.S. national population as reported from Phase 1 of the Third National Health and Nutrition Examination Survey (NHANES III). RESULTS: A total of 1992 individuals (1,009 males and 983 females) were screened for PbB, stratified into age groups, and separated into racial/ethnic categories. Four (0.3%) dust samples and 59 (11.6%) internal and 298 (77.8%) external paint chip samples contained hazardous levels of lead. The geometric mean PbB concentration for people ages 1 year and older reported by NHANES III was 2.8 micro g/dL, compared with 1.5 microg/dL for the military installation cohort (p10 microg/dL for all age groups was 1.6% in the military cohort, compared with 4.5% for the general population. For ages 1-2.9 years, no blacks or Hispanics and 0.6% of whites had PbB levels >10 micro g/dL, compared with 21.6% of blacks, 10.1% of Hispanics, and 8.5% of whites for the general population. For ages 3-5.99 years, 0.15% of blacks, 0% of Hispanics, and 0.3% of whites had PbB levels > or = 10 microg/dL, compared with 20.0% of blacks, 6.8% of Hispanics, and 3.7% of whites for the general population. CONCLUSION: Lead exposure for occupants of on-post military housing is much less than for those residing in the civilian sector. PMID:12500961

  16. 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...... an efficient and individual pain treatment on time. Knowl-edge about how time affect patients pain assessment is important for nurses in order to make patients participate in pain assessment....

  17. System security assessment in real-time using synchrophasor measurements

    DEFF Research Database (Denmark)

    Jóhannsson, Hjörtur; Wache, Markus

    2013-01-01

    assessment and sheds light on ongoing research activities that focus on exploiting wide-area synchrophasor measurements for real-time security assessment of sustainable power systems. At last, an mathematical mapping enabling informative visualization of the system state in respect to aperiodic rotor angle...... measures to ensure stable and secure operation of the system are necessary. Time stamped synchrophasor measurements lay the foundation for development of new real-time applications for security and stability assessment. The paper provides overview of existing solutions for synchrophasor based security...

  18. 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.

  19. Time for the osteopathic profession to take the lead in musculoskeletal research

    OpenAIRE

    Licciardone, John C.

    2009-01-01

    Musculoskeletal conditions, such as low back pain, are prevalent in the United States. These conditions exact an enormous toll on society, both in terms of their detrimental impact on quality of life and on the costs of treatment and lost productivity. Osteopathic physicians, as common providers of primary care services and spinal manipulation, are ideally positioned to lead future research efforts in this field. The emergence of data and standards relevant to osteopathic manipulative treatme...

  20. Factors influencing bone lead concentration in a suburban community assessed by noninvasive K x-ray fluorescence.

    Science.gov (United States)

    Kosnett, M J; Becker, C E; Osterloh, J D; Kelly, T J; Pasta, D J

    1994-01-19

    To determine the influence of demographic, exposure and medical factors on the bone lead concentration of subjects with background (nonindustrial) environmental lead exposure. Survey. Suburban residential community. A total of 101 subjects (49 males, 52 females; aged 11 to 78 years) were recruited from 49 of 123 households geographically located in a suburban residential neighborhood unexposed to any major source of industrial lead emissions. Cortical bone lead concentrations in the midshaft of the tibia were noninvasively measured by in vivo K x-ray fluorescence. Blood lead concentrations were measured by anodic stripping voltammetry. An administered questionnaire assessed potential sources of lead exposure and medical conditions affecting bone metabolism. After the exclusion of one outlier, log-transformed bone lead concentration was highly correlated with age (r = .71; P < or = .0001). Bone lead concentration showed no significant change up to age 20 years, increased with the same slope in men and women between ages 20 and 55 years, and then increased at a faster rate in men older than 55 years. In addition to the variables age and sex, the best fitting multiple regression model for bone lead concentration (R2 = .66; P < or = .0001) revealed a positive correlation with total pack-years of cigarette smoking and a negative correlation with a history of having nursed an infant for longer than 2 weeks. Blood lead concentrations of the subjects were low (geometric mean, 0.24 mumol/L [4.9 micrograms/dL]) and after log transformation were weakly correlated with log-transformed bone lead concentration (r = .23; P = .02). The age- and sex-related increases in bone lead concentration found by K x-ray fluorescence concur with published postmortem studies of bone lead concentration and are consistent with the kinetics of bone turnover and secular trends in lead exposure. These data help to establish a reference range for assessing the lead burden of other populations with

  1. Lead (Pb) quantification in potable water samples: implications for regulatory compliance and assessment of human exposure.

    Science.gov (United States)

    Triantafyllidou, Simoni; Nguyen, Caroline K; Zhang, Yan; Edwards, Marc A

    2013-02-01

    Assessing the health risk from lead (Pb) in potable water requires accurate quantification of the Pb concentration. Under worst-case scenarios of highly contaminated water samples, representative of public health concerns, up to 71-98 % of the total Pb was not quantified if water samples were not mixed thoroughly after standard preservation (i.e., addition of 0.15 % (v/v) HNO(3)). Thorough mixing after standard preservation improved recovery in all samples, but 35-81 % of the total Pb was still un-quantified in some samples. Transfer of samples from one bottle to another also created high errors (40-100 % of the total Pb was un-quantified in transferred samples). Although the United States Environmental Protection Agency's standard protocol avoids most of these errors, certain methods considered EPA-equivalent allow these errors for regulatory compliance sampling. Moreover, routine monitoring for assessment of human Pb exposure in the USA has no standardized protocols for water sample handling and pre-treatment. Overall, while there is no reason to believe that sample handling and pre-treatment dramatically skew regulatory compliance with the US Pb action level, slight variations from one approved protocol to another may cause Pb-in-water health risks to be significantly underestimated, especially for unusual situations of "worst case" individual exposure to highly contaminated water.

  2. Assessment of Science Learning: Living in Interesting Times

    Science.gov (United States)

    Pellegrino, James W.

    2012-01-01

    Beginning with a reference to living in a time of both uncertainty and opportunity, this article presents a discussion of key areas where shared understanding is needed if we are to successfully realize the design and use of high quality, valid assessments of science. The key areas discussed are: (1) assessment purpose and use, (2) the nature of…

  3. Time for the osteopathic profession to take the lead in musculoskeletal research

    Science.gov (United States)

    Licciardone, John C

    2009-01-01

    Musculoskeletal conditions, such as low back pain, are prevalent in the United States. These conditions exact an enormous toll on society, both in terms of their detrimental impact on quality of life and on the costs of treatment and lost productivity. Osteopathic physicians, as common providers of primary care services and spinal manipulation, are ideally positioned to lead future research efforts in this field. The emergence of data and standards relevant to osteopathic manipulative treatment outcomes, refinement of research methodologies to enhance evidence-based medicine, and investments in developing osteopathic research infrastructure are all critical elements in moving this field of research forward. PMID:19624819

  4. 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

  5. Mobile Interventional Stroke Teams Lead to Faster Treatment Times for Thrombectomy in Large Vessel Occlusion.

    Science.gov (United States)

    Wei, Daniel; Oxley, Thomas J; Nistal, Dominic A; Mascitelli, Justin R; Wilson, Natalie; Stein, Laura; Liang, John; Turkheimer, Lena M; Morey, Jacob R; Schwegel, Claire; Awad, Ahmed J; Shoirah, Hazem; Kellner, Christopher P; De Leacy, Reade A; Mayer, Stephan A; Tuhrim, Stanley; Paramasivam, Srinivasan; Mocco, J; Fifi, Johanna T

    2017-12-01

    Endovascular recanalization treatment for acute ischemic stroke is a complex, time-sensitive intervention. Trip-and-treat is an interhospital service delivery model that has not previously been evaluated in the literature and consists of a shared mobile interventional stroke team that travels to primary stroke centers to provide on-site interventional capability. We compared treatment times between the trip-and-treat model and the traditional drip-and-ship model. We performed a retrospective analysis on 86 consecutive eligible patients with acute ischemic stroke secondary to large vessel occlusion who received endovascular treatment at 4 hospitals in Manhattan. Patients were divided into 2 cohorts: trip-and-treat (n=39) and drip-and-ship (n=47). The primary outcome was initial door-to-puncture time, defined as the time between arrival at any hospital and arterial puncture. We also recorded and analyzed the times of last known well, IV-tPA (intravenous tissue-type plasminogen activator) administration, transfer, and reperfusion. Mean initial door-to-puncture time was 143 minutes for trip-and-treat and 222 minutes for drip-and-ship ( P Stroke Scale for trip-and-treat compared with drip-and-ship ( P =0.0704). Compared with drip-and-ship, the trip-and-treat model demonstrated shorter treatment times for endovascular therapy in our series. The trip-and-treat model offers a valid alternative to current interhospital stroke transfers in urban environments. © 2017 American Heart Association, Inc.

  6. 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

  7. Does increased prehospital time lead to a "trial of life" effect for patients with blunt trauma?

    Science.gov (United States)

    Clements, Thomas W; Vogt, Kelly; Hameed, S Morad; Parry, Neil; Kirkpatrick, Andrew W; Grondin, Sean C; Dixon, Elijah; McKee, Jessica; Ball, Chad G

    2017-08-01

    Variance in prehospital time among severely injured blunt trauma patients is dependent upon numerous factors. Effects on subsequent mortality and trauma team activation (TTA) rates are also unclear. The primary aim of this study was to evaluate the relationship between prehospital time and mortality at level I trauma referral centers amongst critically blunt injured patients. This multiinstitutional study from three geographically distinct level I trauma centers analyzed all severely blunt injured patients (Injury Severity Score [ISS] ≥12). The relationship between prehospital time and survival was evaluated. Secondary outcomes included the association between prehospital time and TTA. Standard statistical methodology was used (P prehospital time interval increased, overall mortality decreased (0-30 min = 24.1%; 31-60 min = 14.7%; 61-90 min = 10.3%; 91-120 min = 10.4%; 121-150 min = 10.2%; P prehospital times have a substantially lower risk of subsequent mortality. This concept should contribute to decision-making with regard to TTA. Copyright © 2017 Elsevier Inc. All rights reserved.

  8. 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

    2015-01-01

    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. PMID:25646487

  9. assessment of public willingness to commit time to urban forestry ...

    African Journals Online (AJOL)

    DR AJEWOLE

    urban forestry development in the metropolis and the factors that can influence both the willingness to commit .... In order to assess the factors affecting the public willingness to commit time to urban forestry development in .... actively involved in career development and may not have the time to spare for participatory UFD.

  10. Cranial trauma and the assessment of posttraumatic survival time

    NARCIS (Netherlands)

    Steyn, M.; de Boer, H. H. [=Hans H.; van der Merwe, A. E.

    2014-01-01

    Assessment of trauma on skeletal remains can be very difficult, especially when it comes to the estimation of posttraumatic survival time in partially healed lesions. The ability to reliably estimate the time an individual has survived after sustaining an injury is especially important in cases of

  11. Assessment of Genotoxicity through ISSR Marker in Pistia stratiotes Induced by Lead

    Directory of Open Access Journals (Sweden)

    Lamyai Neeratanaphan

    2014-06-01

    Full Text Available Assessment of DNA changes in Pistia stratiotes induced by lead (Pb, plants were grown in acclimatized conditions for 15 days. Each of 5 plants were then transferred to cultivate in three repeated 0.2, 0.3, 0.5 mg/l Pb experiments, four days and controls. Lead concentration in water was analyzed by inductively-coupled plasma - mass spectrometry (ICP-MS, physical and chemical factors including temperature, pH, dissolved oxygen (DO and electro-conductivity (EC before and after the experimentation. Inter-simple sequence repeat fingerprints (ISSR were analyzed for genetic similarity values (S, and genomic template stability test (GTS was evaluated for revealing correlation of genetic structure changes and induced Pb concentration levels. The results appeared that the mean Pb concentrations in water were decreased 0.0121, 0.1688 and 0.2338 mg/l in the 3 concentration experiments, respectively. Assumedly, these Pb values loosed were adsorbed and absorbed in the plants. The physical and chemical factors such as pH, DO and EC were decreased and temperature was increased. The 10 successfully ISSR primers produced a total of 577 bands used for dendrogram construction. The plants with Pb affected 0.2, 0.3 and 0.5 mg/l were correlated by each concentration grouping and the S reveals 0.85-0.90, 0.69-0.90 and 0.93-0.96, respectively. The S value and plant's individual grouping agreement reveal its true effect by each Pb concentration. GTS values were (-2.38 - (-23.81 signifying to have most changes in DNA structure, genetic erosion occurring thoroughly on its genome, and affecting its life. These effects agreed to its morphological characters including leaves lacking chlorophyll (yellow, beginning to decay and finally dying. The research shows that P. stratiotes can be used as a bio-indicator for Pb wastewater monitoring.

  12. 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 CO2 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.

  13. 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.

  14. 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.

  15. 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

  16. Action and perception are temporally coupled by a common mechanism that leads to a timing misperception.

    Science.gov (United States)

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

    2015-01-28

    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. Copyright © 2015 the authors 0270-6474/15/351493-12$15.00/0.

  17. 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

  18. Identifying patients at risk of nursing home admission: The Leeds Elderly Assessment Dependency Screening tool (LEADS

    Directory of Open Access Journals (Sweden)

    Fear Jon

    2006-03-01

    Full Text Available Abstract Background Discharge from hospital to a nursing home represents a major event in the life of an older person and should only follow a comprehensive functional and medical assessment. A previous study identified 3 dependency scales able to discriminate across outcomes for older people admitted to an acute setting. We wished to determine if a single dependency scale derived from the 3 scales could be created. In addition could this new scale with other predictors be used as a comprehensive tool to identify patients at risk of nursing home admission. Methods Items from the 3 scales were combined and analysed using Rasch Analysis. Sensitivity and specificity analysis and ROC curves were applied to identify the most appropriate cut score. Binary logistic regression using this cut-off, and other predictive variables, were used to create a predictive algorithm score. Sensitivity, specificity and likelihood ratio scores of the algorithm scores were used to identify the best predictive score for risk of nursing home placement. Results A 17-item (LEADS scale was derived, which together with four other indicators, had a sensitivity of 88% for patients at risk of nursing home placement, and a specificity of 85% for not needing a nursing home placement, within 2 weeks of admission. Conclusion A combined short 17-item scale of dependency plus other predictive variables can assess the risk of nursing home placement for older people in an acute care setting within 2 weeks of admission. This gives an opportunity for either early discharge planning, or therapeutic intervention to offset the risk of placement.

  19. Proximity of pacemaker and implantable cardioverter-defibrillator leads to coronary arteries as assessed by cardiac computed tomography.

    Science.gov (United States)

    Pang, Benjamin J; Joshi, Subodh B; Lui, Elaine H; Tacey, Mark A; Alison, Jeff; Seneviratne, Sujith K; Cameron, James D; Mond, Harry G

    2014-06-01

    There have been rare case reports of damage to adjacent coronary arteries by screw-in pacemaker and implantable cardioverter-defibrillator (ICD) leads. Our aim was to assess the proximity of pacemaker and ICD leads to the major coronary anatomy using cardiac computed tomography (CT). Cardiac CT images were retrospectively analyzed to assess the spatial relationship of device lead tips to the major coronary anatomy. Fifty-two right ventricular (RV) leads (17 apical, 35 nonapical) and 35 right atrial (RA) leads were assessed. Leads on the RV antero-septal junction (20 of 52) were close (median 4.7 mm) to, and orientated toward, the left anterior descending (LAD) coronary artery. RA leads in the anterior (26 of 35) and lateral (seven of 35) walls of the RA appendage were not close to (16.9 ± 7.7 mm and 18.9 ± 12.4 mm, respectively) and directed away from the right coronary artery. However, an RA lead adjacent to the superior border of the tricuspid valve was 4.3 mm from the right coronary artery and an RA lead on the medial wall of the RA appendage was 1.6 mm away from the aorta. An RV pacemaker lead in the lateral wall of the RV inlet was 3.4 mm from the right coronary artery. In our cohort, a majority of RV leads were on the antero-septal junction and close to the overlying LAD coronary artery. RA leads adjacent to the tricuspid valve or on the medial RA appendage were in close proximity to the right coronary artery and aorta, respectively. ©2013 Wiley Periodicals, Inc.

  20. 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

    2008-01-01

    Describe the development of the leading by example (LBE) instrument. A total of 135 responses from employees of a private corporation working at 11 different worksites were factor analyzed in 2005. Exploratory factor analysis was used to obtain an initial factor structure. Factor validity was evaluated using confirmatory factor analysis methods. A second sample was collected in 2006 from the same population (N = 178) and was used to confirm the factor structure via confirmatory factor analysis. Cronbach's alpha and item-total correlations provided information on the reliability of the factor subscales. Four subscales were identified: business alignment with health promotion objectives, awareness of the health-productivity link, worksite support for health promotion, and leadership support for health promotion. Factor by group comparisons revealed that the initial factor structure was effective in detecting differences in organizational support for health promotion across different employee groups. 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.

  1. Assessment of the Interstellar Processes Leading to Deuterium Enrichment in Meteoritic Organics

    Science.gov (United States)

    Sandford, Scott A.; Bernstein, Max P.; Dworkin, Jason P.; DeVincenzi, Donald L. (Technical Monitor)

    2001-01-01

    The presence of isotopic anomalies is the most unequivocal demonstration that meteoritic material contains circumstellar or interstellar components. In the case of organic compounds in meteorites and interplanetary dust particles (IDPs), the most useful isotopic tracer has been deuterium (D). We discuss four processes that are expected to lead to D enrichment in interstellar materials and describe how their unique characteristics can be used to assess their relative importance for the organics in meteorites. These enrichment processes are low temperature gas phase ion-molecule reactions, low temperature gas-grain reactions, gas phase unimolecular photodissociation, and ultraviolet photolysis in D-enriched ice mantles. Each of these processes is expected to be associated with distinct regiochemical signatures (D placement on the product molecules, correlation with specific chemical functionalities, etc.), especially in the molecular population of polycyclic aromatic hydrocarbons (PAHs). We describe these differences and discuss how they may be used to delineate the various interstellar processes that may have contributed to meteoritic D enrichments. We also briefly discuss how these processes may affect the isotopic distributions in C, 0, and N in the same compounds.

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

    Science.gov (United States)

    2017-01-13

    completion rate should be observed. This new method would achieve improved results from the 75% on-time completion rate at present. The final...provide a future forecast to the First Pass Yield team on the FPY they could achieve given X amount of improvement in quality. While a full model was...of the negative binomial distribution simple given an appropriate understanding of the software and an un - derstanding of the components of the

  3. The decrease in population bone lead levels in Canada between 1993 and 2010 as assessed by in vivo XRF.

    Science.gov (United States)

    McNeill, F E; Fisher, M; Chettle, D R; Inskip, M; Healey, N; Bray, R; Webber, C E; Manton, W I; Marro, L; Arbuckle, T E

    2017-12-28

    Objective and Approach: A study, conducted in Toronto, Canada, between 2009 and 2011, measured the bone lead concentrations of volunteers aged 1-82 years using in vivo x-ray fluorescence (XRF) technology. Bone lead levels were lower compared to Ontario in vivo XRF studies from the early 1990s. In adults, the slope of tibia lead content versus age was reduced by 36-56%, i.e. bone lead levels for a given age group were approximately half compared to the same age group 17 years prior. Further, bone lead levels of individuals fell over that time period. In 2010, an average person aged 57 years had a bone lead level approximately 1/3 less than their bone lead level age 40 years in 1993. Using this data, the half-lives of lead in the tibia were estimated as 7-26 years. Tibia lead levels were found to be low in children. The reduction in bone tibia content in children was not significant (p  =  0.07), but using data from additional north eastern US studies, there is evidence that childhood tibia stores are lower than in the 1990s. In vivo XRF analysis shows that there has been a reduction in the level of lead in bone in Canada over the last two decades. Public health measures have been very successful in reducing ongoing exposure to lead and in reducing bone lead stores.

  4. Detailed Maintenance Planning for Military Systems with Random Lead Times and Cannibalization

    Science.gov (United States)

    2014-12-01

    in a time period depends on the number of functioning PEs at the beginning of the period. Using the theory of Markov decision process (MDP), Zhang [8...Marti, K. (2005), Stochastic Optimization Methods, Springer, Berlin. [13] Barlow, R. E. and Proschan, F. (1965), Mathematical Theory of Reliability...couramment utilisées par le personnel de maintenance pour réparer des systèmes d’arme défectueux est la cannibalisation. En raison des difficultés que

  5. 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.

  6. 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.

  7. 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.

  8. 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

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

    Science.gov (United States)

    Zunino, Luciano; Olivares, Felipe; Scholkmann, Felix; Rosso, Osvaldo A.

    2017-06-01

    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.

  10. Real-time Color Codes for Assessing Learning Process

    OpenAIRE

    Dzelzkaleja, Laura; Kapenieks, Janis

    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...

  11. Lead Slowing-Down Spectrometry Time Spectral Analysis for Spent Fuel Assay: FY11 Status Report

    Energy Technology Data Exchange (ETDEWEB)

    Kulisek, Jonathan A.; Anderson, Kevin K.; Bowyer, Sonya M.; Casella, Andrew M.; Gesh, Christopher J.; Warren, Glen A.

    2011-09-30

    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 assay methods. This document is a progress report for FY2011 PNNL analysis and algorithm development. Progress made by PNNL in FY2011 continues to indicate the promise of LSDS analysis and algorithms applied to used fuel. PNNL developed an empirical model based on calibration of the LSDS to responses generated from well-characterized used fuel. The empirical model, which accounts for self-shielding effects using empirical basis vectors calculated from the singular value decomposition (SVD) of a matrix containing the true self-shielding functions of the used fuel assembly models. The potential for the direct and independent assay of the sum of the masses of 239Pu and 241Pu to within approximately 3% over a wide used fuel parameter space was demonstrated. Also, in FY2011, PNNL continued to develop an analytical model. Such efforts included the addition of six more non-fissile absorbers in the analytical shielding function and the non-uniformity of the neutron flux across the LSDS assay chamber. A hybrid analytical-empirical approach was developed to determine the mass of total Pu (sum of the masses of 239Pu, 240Pu, and 241Pu), which is an important quantity in safeguards. Results using this hybrid method were of approximately the same accuracy as the

  12. 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. Develo....... 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....

  13. 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.

  14. Assessment of inorganic lead species and total organo-alkyllead in some Egyptian agricultural soils.

    Science.gov (United States)

    Elsokkary, I H; Amer, M A; Shalaby, E A

    1995-01-01

    This study was carried out to assess the amounts of (i) total Pb in soil, (ii) inorganic Pb species: exchangeable (EXCH), carbonate (CARB), easily reducible (EASR), moderately reducible (MODR), organic matter and sulfides (ORGS), and residual (RESD) bound Pb, and (iii) total organo-lead as alkyllead, in alluvial and lacustrine soils of the Nile delta, Egypt. Wide ranges of soil Pb were found in the alluvial (18.2-1850 microg g(-1)) and the lacustrine (39-1985 microg g(-1)) soils. The topsoil was highly enriched with Pb relative to the subsurface soils, especially in highly contaminated soils. There was no significant relationship between soil type and Pb content. Amounts of soil Pb greater than the background level (14 microg g(-1)) are due to Pb deposited from various anthropogenic activities. The partitioning of soil Pb into different species varied according to the intensity of contamination. It followed the sequence: RESD > ORGS > CARB > MODR > EASR in the slightly contaminated alluvial as well as lacustrine soils. In the highly contaminated soils, it followed the sequence: ORGS > MODR > CARB > EASR > RESD in the alluvial soils, and the sequence: ORGS > CARB > MODR > EASR > RESD in the lacustrine soils. There is high binding capacity of organic matter and sulfides to Pb, especially in the highly contaminated soils. The concentrations of total alkyllead in soils varied markedly and were related to both intensity of contamination and depth in the soil. The subsurface soil (15-30 cm) was highly enriched by alkyllead (means 224 and 353 ng g(-1) in the alluvial and lacustrine soils, respectively) relative to the surface and deeper soils. The proportion of total alkyllead as a percentage of total Pb in the soil was generally very low. It did not exceed 1.6% in the slightly contaminated soils, and 0.6% in the highly contaminated ones.

  15. 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.

  16. 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.

  17. Real-time PCR quantitative assessment of hepatitis A virus ...

    African Journals Online (AJOL)

    We applied real-time RT-PCR (reverse transcription-polymerase chain reaction) to assess the incidence of hepatitis A virus, rotaviruses and enteroviruses in the Tyume River, an important water resource in the impoverished Eastern Cape Province of South Africa. Detection of noroviruses was done using conventional ...

  18. 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 ...

  19. Quantifying the Bullwhip Effect in a Simple Supply Chain: The Impact of Forecasting, Lead Times, and Information

    OpenAIRE

    Frank Chen; Zvi Drezner; Ryan, Jennifer K.; David Simchi-Levi

    2000-01-01

    An important observation in supply chain management, known as the bullwhip effect, suggests that demand variability increases as one moves up a supply chain. In this paper we quantify this effect for simple, two-stage supply chains consisting of a single retailer and a single manufacturer. Our model includes two of the factors commonly assumed to cause the bullwhip effect: demand forecasting and order lead times. We extend these results to multiple-stage supply chains with and without central...

  20. (Q, R inventory model with service level constraint and variable lead time in fuzzy-stochastic environment

    Directory of Open Access Journals (Sweden)

    Hardik Soni

    2011-10-01

    Full Text Available In today's global marketplace, individual firms do not compete as independent entities rather as an integral part of a supply chain. Uncertainty is the main attribute in managing the supply chains. Accordingly, we develop a (Q, R inventory model with service level constraint and variable lead-time in fuzzy-stochastic environment. In addition, the triangular fuzzy numbers counts upon lead-time are used to construct fuzzy-stochastic lead-time demand. Using credibility criterion, the expected shortages are calculated. Without loss of generality, we assume that all the observed values of the fuzzy random variable, representing the demand are triangular fuzzy numbers. Consequently, the value of total expected cost in the fuzzy sense is derived using the expected value criterion or credibility criterion. To determine an optimal policy, a numerical technique is presented and the results are analyzed using scan and zoom for constraint optimization. Finally, in order to demonstrate the accuracy and effectiveness of the proposed model, numerical example and sensitivity analysis are also included.

  1. Effect of Kiwi Shell and Incubation Time on Mobility of Lead and Cadmium in Contaminated Clay Soil

    Directory of Open Access Journals (Sweden)

    Bahareh Lorestani

    2014-06-01

    Full Text Available In this study, the effectiveness of kiwi shell was investigated to reduce the mobility of Lead and Cadmium in clay soil in different intervals. For this purpose a clay soil sample was contaminated with Lead and Cadmium in distinct dishes with 10 and 600 ppm concentrations respectively and mixed with 5% kiwi shell. Samples were placed in incubator, and then sampling of soil in incubator was performed in intervals 3 hours, 1, 3, 7, 14, 21 and 28 days. Heavy metals concentrations were determined in different fractions of soil including exchangeable, carbonate, Fe-Mn oxides, organic matter, and residual with sequential extraction procedure and atomic absorption spectrophotometry. The results showed that during incubation, Lead concentration in treatments with kiwi shell rather than control soil increased in carbonate from 19.48 to 26.18 and in organic matter from 9.06 to 18.66 percent. Exchangeable, Fe-Mn oxides and residual fractions decreased from 11.48 to 6.69, 45.72 to 39.83 and 14.21 to 7.90 percent respectively. In samples with absorbent compared with control soil, Cadmium concentration in carbonate and organic matter increased from 28.20 to 38.40 and 18.76 to 24.72, while in exchangeable, Fe-Mn oxides and residual decreased from 16.66 to 13.69, 37.25 to 19.65 and 6.24 to 3.61 percent respectively. This study revealed that kiwi shell function in decreasing Cadmium and Lead mobility in studied clay soil were increased with increasing incubation time, but Cadmium compared with Lead required additional time to transfer and mobility to constant and stable soil fractions such as, organic matter and Fe-Mn oxides.

  2. 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.

  3. Assessment of elemental concentrations in streams of the New Lead Belt in southeastern Missouri, 2002-05

    Science.gov (United States)

    Brumbaugh, William G.; May, Thomas W.; Besser, John M.; Allert, Ann L.; Schmitt, Christopher J.

    2007-01-01

    Concerns about possible effects of lead-mining activities on the water quality of federally protected streams located in southeastern Missouri prompted a suite of multidisciplinary studies to be conducted by the U.S. Geological Survey. As part of this investigation, a series of biological studies were initiated in 2001 for streams in the current mining region and the prospecting area. In this report, results are examined for trace elements and other selected chemical measurements in sediment, surface water, and sediment interstitial (pore) water sampled between 2002 and 2005 in association with these biological studies. Compared to reference sites, fine sediments collected downstream from mining areas were enriched in metals by factors as large as 75 for cadmium, 62 for cobalt, 171 for nickel, 95 for lead, and 150 for zinc. Greatest metal concentrations in sediments collected in 2002 were from sites downstream from mines on Strother Creek, Courtois Creek, and the West Fork Black River. Sediments from sites on Bee Fork, Logan Creek, and Sweetwater Creek also were noticeably enriched in lead. Sediments in Clearwater Lake, at least 75 kilometers downstream from mining activity, had metal concentrations that were 1.5 to 2.1 times greater than sediments in an area of the lake with no upstream mining activity. Longitudinal sampling along three streams in 2004 indicated that sediment metal concentrations decreased considerably a few kilometers downstream from mining activities; however, in Strother Creek some metals were still enriched by a factor of five or more as far as 13 kilometers downstream from the Buick tailings impoundment. Compared with 2002 samples, metals concentrations were dramatically lower in sediments collected in 2004 at an upper West Fork Black River site, presumably because beneficiation operations at the West Fork mill ceased in 2000. Concentrations of metals and sulfate in sediment interstitial (pore) waters generally tracked closely with metal

  4. Mortality of lead smelter workers: A follow-up study with exposure assessment.

    Science.gov (United States)

    Bertke, Stephen J; Lehman, Everett J; Wurzelbacher, Steven J; Hein, Misty J

    2016-11-01

    Lead exposure has been linked to impaired renal function and kidney failure. High lead exposures have been associated with increased mortality from certain cancers, hypertension, cardiovascular disease, and amyotrophic lateral sclerosis (ALS). We extended vital status follow-up on a cohort of 1,990 lead smelter workers by 25 years and computed standardized mortality ratios and rate ratios (RR) stratified by cumulative lead exposure. The update added 13,823 person-years at risk and 721 deaths. Increased risk of mortality was observed for the a priori outcomes of lung cancer, cardiovascular disease (including cerebrovascular disease), chronic kidney disease, and ALS. However, of these outcomes, only cardiovascular, cerebrovascular, and chronic kidney diseases were associated with a positive exposure-response in RR analyses. This study reaffirms the association of lead exposure with cardiovascular and kidney diseases; however, increased mortality observed for certain cancers is not likely to be due to lead exposure. Am. J. Ind. Med. 59:979-986, 2016. Published 2016. This article is a U.S. Government work and is in the public domain in the USA. Published 2016. This article is a U.S. Government work and is in the public domain in the USA.

  5. 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  µ g/g and 4.08-60.20  µ g/g, respectively. The eye shadow samples had a lead level of 0.85-6.90  µ g/g and a cadmium level of 1.54-55.59  µ g/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.

  6. 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

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

    Directory of Open Access Journals (Sweden)

    H. Nourmoradi

    2013-01-01

    Full Text Available 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.

  8. 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.

  9. Global collaborative healthcare: assessing the resource requirements at a leading Academic Medical Center.

    Science.gov (United States)

    Rosson, Nicole J; Hassoun, Heitham T

    2017-09-20

    Academic Medical Centers ("AMCs") have served as a hub of the United States ("US") health system and represented the state-of-the art in American health care for well over a century. Currently, the global healthcare market is both massive and expanding and is being altered by the unprecedented impact of technological advances and globalization. This provides AMCs a platform to enter into trans-national collaborative partnerships with healthcare organizations around the world, thus providing a means to deliver on its promise globally while also expanding and diversifying its resources. A number of leading US AMCs have engaged in global collaborative healthcare, employing different models based on services offered, global distribution, and inclination to assume risk. Engaging in these collaborations requires significant effort from across the health system, and an understanding of the resources required is paramount for effective delivery and to avoid overextension and diversion from the primary mission of these organizations. The goal of this paper is to discuss the role of US AMCs in this current global healthcare landscape and to also investigate our institutional faculty and staff resource requirements to support the operating model. We extracted and retrospectively analyzed data from the JHI Global Services database for a 3-year period (Jan, 2013-Dec, 2015) to determine total utilization (hours and full time equivalent (FTE)), utilization by profession, and clinical and non-clinical areas of expertise. JHI utilized on average 21,940 h annually, or 10.55 FTEs of faculty and staff subject matter experts. The majority of the hours are for work performed by physician faculty members from 23 departments within the School of Medicine, representing 77% percent or on average 16,894 h annually. Clinical and allied health departments had an average annual utilization of 17,642 h or 7.8 FTEs, while non-clinical departments, schools and institutes averaged 4298 h or 1

  10. 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.

  11. 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.

  12. Assessing the mechanism of DNA damage induced by lead through direct and indirect interactions.

    Science.gov (United States)

    Zhang, Hao; Wei, Kai; Zhang, Mengyu; Liu, Rutao; Chen, Yadong

    2014-07-05

    Lead still possesses great threats to human health owing to its widespread distribution in the environment caused by human activities, although various actions have been taken to cut down the use and distribution of lead. In this work, mechanisms of DNA damage caused by lead through indirect and direct interactions were investigated. Results from comet assay showed lead at 1-10 μM induced DNA strand breaks in mice liver cells according to olive tail moment analysis. Signals of DNA-protein crosslinks (DPC) were not significantly detected until exposed at 100 μM Pb(2+). Further more, direct interactions between Pb(2+) and DNA were explored to determine the binding mode between them using spectra analysis, isothermal titration calorimetry studies and molecular docking investigations, which indicated that Pb(2+) could bind to DNA with four binding sites to form Pb(2)(+)-DNA complex by minor groove binding effects and electrostatic forces, resulting in damage to the structure of DNA double helix. Combined studies of lead genotoxicity in indirect (comet assay and DPC assay) and direct (binding mode investigations) interactions can be applied to study the potential damages to DNA induced by heavy metal pollutants. Copyright © 2014 Elsevier B.V. All rights reserved.

  13. Time Encoded Signal Processing for Speech Quality Assessment

    OpenAIRE

    Kraljevski, Ivan; Stojanovic, Igor; Chungurski, Slavco; Arsenovski, Sime

    2010-01-01

    In this paper a method for speech quality assessment is described and evaluated simulating transmission of AMR-NB encoded speech over noisy GSM channel. The proposed system uses comparison of Time Encoded Signal (TES) processing of speech sequences, where one original and one degraded speech signal were transmitted trough GSM simulation system with AWGN noise channel. Several tests have been made on reference speech sample of single speaker with simulated bit-error loss effects on the perc...

  14. Comparison of home lead dust reduction techniques on hard surfaces: the New Jersey assessment of cleaning techniques trial.

    OpenAIRE

    Rich, David Q; Rhoads, George G; Yiin, Lih-Ming; Zhang, Junfeng; Bai, Zhipeng; Adgate, John L; Ashley, Peter J; Lioy, Paul J

    2002-01-01

    High efficiency particulate air filter (HEPA) vacuums, which collect particles > 0.3 micro m, and trisodium phosphate (TSP), a detergent claimed to selectively remove lead, have been included in the HUD Guidelines for the Evaluation and Control of Lead Based Paint Hazards in Housing without systematic validation of their effectiveness. At the time the study was initiated, both HEPA vacuums and TSP were relatively expensive, they were not readily found in urban retail centers, and there were e...

  15. The application of EOQ and lead time crashing cost models in material with limited life time (Case study: CN-235 Aircraft at PT Dirgantara Indonesia)

    Science.gov (United States)

    Agustina Hidayat, Yosi; Ria Kasanah, Aprilia; Yudhistira, Titah

    2016-02-01

    PT. Dirgantara Indonesia, one of State Owned Enterprises engaging in the aerospace industry, targets to control 30% of world market for light and medium sized aircraft. One type of the aircrafts produced by PT. DI every year is CN-235. Currently, the cost of material procurement reaches 50% of the total cost of production. Material has a variety of characteristics, one of which is having a lifetime. The demand characteristic of the material with expiration for the CN-235 aircraft is deterministic. PT DI does not have any scientific background for its procurement of raw material policy. In addition, there are two methods of transportation used for delivering materials, i.e. by land and air. Each method has different lead time. Inventory policies used in this research are deterministic and probabilistic. Both deterministic and probabilistic single and multi-item inventory policies have order quantity, time to order, reorder point, and lead time as decision variables. The performance indicator for this research is total inventory cost. Inventory policy using the single item EOQ and considering expiration factor inventory results in a reduction in total costs up to 69.58% and multi item results in a decrease in total costs amounted to 71.16%. Inventory policy proposal using the model of a single item by considering expiration factor and lead time crashing cost results in a decrease in total costs amounted to 71.5% and multi item results in a decrease in total costs amounted to 71.62%. Subsequently, wasted expired materials, with the proposed models have been successfully decreased to 95%.

  16. 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…

  17. 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…

  18. 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...

  19. 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.

  20. assessment of cadmium and lead in soil and tomatoes grown in ...

    African Journals Online (AJOL)

    MAHMUD IMAM

    sources of contamination such as fertilizers, pesticides, sewage sludge and organic waste. Keywords: Soil ... stations. Lead can trigger both acute and chronic symptoms of poisoning. Acute intoxication only occurs through the consumption of relatively large doses of .... irrigation by municipal waste water on a daily basis. 18.

  1. 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.

  2. Assessment of levels of copper, cadmium and lead in secretion of ...

    African Journals Online (AJOL)

    The levels of copper, cadmium and lead were determined in milk samples from cows grazed on open fields. The use of H2O2 cleared the residual colours of the metal solutions following digestion with HNO3 acid. The results of the Atomic Absorption Spectrophotometric analysis of the metal solutions from the milk samples ...

  3. Learning to Lead Organizational Change: Assessment of a Problem-Based Simulation in Thailand

    Science.gov (United States)

    Hallinger, Philip; Lu, Jiafang; Showanasai, Parinya

    2010-01-01

    This paper presents findings of a study that evaluated the instructional effectiveness of a problem-based learning module constructed around a computer simulation, "Making Change Happen"[TM]. The "Leading Organizational Change" (LOC) course sought to enable students in a graduate management program in Thailand to learn to lead…

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

    Science.gov (United States)

    2007-08-01

    Jenne, E. A. 1968. Controls on Mn , Fe, Co, Ni, Cu and Zn concentrations in soils and water: The significant role of hydrous Mn and Fe oxides...T. J. Logan, and J. A. Ryan. 1993. In-situ immobilization of lead by apatite . Environmental Science and Technology. 27:1803–1810. MAARNG. 2006

  5. Solution and vapour deposited lead perovskite solar cells: Ecotoxicity from a life cycle assessment perspective

    DEFF Research Database (Denmark)

    Espinosa Martinez, Nieves; Serrano-Luján, Lucía; Urbina, Antonio

    2015-01-01

    We present a life cycle analysis (LCA) and an environmental impact analysis (EIA) of lead based perovskite solar cells prepared according to the two most successfully reported literature methods that comprise either vapour phase deposition or solution phase deposition. We have developed the inven......We present a life cycle analysis (LCA) and an environmental impact analysis (EIA) of lead based perovskite solar cells prepared according to the two most successfully reported literature methods that comprise either vapour phase deposition or solution phase deposition. We have developed...... in the analysis and further present a sensitivity analysis with the operational lifetime as a basis. We find that the major impact comes from the preparation of the perovskite absorber layer due to the electrical energy required in the manufacture and also make the striking observation that the impact of toxic...... lead(II)halides is very limited compared to methylammoniumhalides employed. This applies during the raw materials extraction, synthesis of the starting materials and manufacture of the perovskite solar cells and from these points of view the lead based perovskite solar cells do not pose extra concerns...

  6. 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.

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

    Science.gov (United States)

    2012-01-01

    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. PMID:23369182

  8. 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.

  9. High Resolution Space-Time Ozone Modeling for Assessing Trends.

    Science.gov (United States)

    Sahu, Sujit K; Gelfand, Alan E; Holland, David M

    2007-01-01

    The assessment of air pollution regulatory programs designed to improve ground level ozone concentrations is a topic of considerable interest to environmental managers. To aid this assessment, it is necessary to model the space-time behavior of ozone for predicting summaries of ozone across spatial domains of interest and for the detection of long-term trends at monitoring sites. These trends, adjusted for the effects of meteorological variables, are needed for determining the effectiveness of pollution control programs in terms of their magnitude and uncertainties across space. This paper proposes a space-time model for daily 8-hour maximum ozone levels to provide input to regulatory activities: detection, evaluation, and analysis of spatial patterns of ozone summaries and temporal trends. The model is applied to analyzing data from the state of Ohio which has been chosen because it contains a mix of urban, suburban, and rural ozone monitoring sites in several large cities separated by large rural areas. The proposed space-time model is auto-regressive and incorporates the most important meteorological variables observed at a collection of ozone monitoring sites as well as at several weather stations where ozone levels have not been observed. This problem of misalignment of ozone and meteorological data is overcome by spatial modeling of the latter. In so doing we adopt an approach based on the successive daily increments in meteorological variables. With regard to modeling, the increment (or change-in-meteorology) process proves more attractive than working directly with the meteorology process, without sacrificing any desired inference. The full model is specified within a Bayesian framework and is fitted using MCMC techniques. Hence, full inference with regard to model unknowns is available as well as for predictions in time and space, evaluation of annual summaries and assessment of trends.

  10. Extract fetal ECG from single-lead abdominal ECG by de-shape short time Fourier transform and nonlocal median

    CERN Document Server

    Li, Su

    2016-01-01

    The multiple fundamental frequency detection problem and the source separation problem from a single-channel signal containing multiple oscillatory components and a nonstationary noise are both challenging tasks. To extract the fetal electrocardiogram (ECG) from a single-lead maternal abdominal ECG, we face both challenges. In this paper, we propose a novel method to extract the fetal ECG signal from the single channel maternal abdominal ECG signal, without any additional measurement. The algorithm is composed of three main ingredients. First, the maternal and fetal heart rates are estimated by the de-shape short time Fourier transform, which is a recently proposed nonlinear time-frequency analysis technique; second, the beat tracking technique is applied to accurately obtain the maternal and fetal R peaks; third, the maternal and fetal ECG waveforms are established by the nonlocal median. The algorithm is evaluated on a simulated fetal ECG signal database ({\\em fecgsyn} database), and tested on two real data...

  11. 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.

  12. 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.

  13. 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.

  14. 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 206Pb/207Pb 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 (Cuba.

  15. Real-time risk assessment of operational events

    Energy Technology Data Exchange (ETDEWEB)

    Perryman, L.J. [Nuclear Safety Div., Johannesburg (South Africa). Technol. Group; Foster, N.A.S. [Nuclear Safety Div., Johannesburg (South Africa). Technol. Group; Nicholls, D.R. [Nuclear Safety Div., Johannesburg (South Africa). Technol. Group; Grobbelaar, J.F. [Nuclear Safety Div., Johannesburg (South Africa). Technol. Group

    1996-02-01

    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.).

  16. Using oceanic-atmospheric oscillations for long lead-time streamflow forecasting in the Upper Colorado River Basin

    Science.gov (United States)

    Kalra, A.; Ahmad, S.

    2007-12-01

    In the recent past, oceanic-atmospheric oscillations have been used successfully for long lead-time streamflow forecasting. Herein, we present a data-driven model, Support Vector Machine (SVM) for the long lead-time streamflow forecast incorporating oceanic-atmospheric oscillations. The SVM is based on Statistical Learning Theory that uses a hypothesis space of linear functions based on Kernel approach and can be used to predict a quantity forward in time based on training that uses past data. The principal strength of SVM lies in minimizing the empirical classification error and maximizing the geometric margin by solving inverse problems. The SVMs are considered superior to the Artificial Neural Networks (ANNs) due to the tendency of formulating a quadratic optimization problem which ensures a global optimum that is found missing in the traditional ANN approach. The SVM model was applied to four unimpaired gages in the Upper Colorado River Basin (UCRB). The streamflow data for the selected gages was used from 1906¡§C2004. Annual oceanic-atmospheric indexes comprising of Pacific Decadal Oscillation (PDO), North Atlantic Oscillation (NAO), Atlantic Multidecadal Oscillation (AMO), and El Nino-Southern Oscillations (ENSO) for a period of 1906¡§C2001 were used to generate streamflow volumes for three years ahead. The SVM model was trained with 86 years of data (1906¡§C1991) and tested for 10 years of data (1992-2001). The testing criteria used for the model effectiveness was based on correlation coefficient r, root means square error (RMSE) and nash sutcliffe efficiency coefficient e. Predictions during the testing phase showed a good agreement with measured streamflow volumes for the selected gages in UCRB. Rigorous sensitivity analysis was performed to evaluate the effect of individual oscillation. The results indicated a strong signal for NAO and ENSO indexes as compared to PDO and AMO indexes for the long lead-time streamflow forecast. The oceanic

  17. 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.

  18. The biostability of cardiac lead insulation materials as assessed from long-term human implants.

    Science.gov (United States)

    Wilkoff, Bruce L; Rickard, John; Tkatchouk, Ekaterina; Padsalgikar, Ajay D; Gallagher, Genevieve; Runt, James

    2016-02-01

    Accelerated in vitro biostability studies are useful for making relativistic comparisons between materials. However, no in vitro study can completely replicate the complex biochemical and biomechanical environment that a material experiences in the human body. To overcome this limitation, three insulation materials [Optim™ insulation (OPT), Pellethane® 55D (P55D), and silicone elastomer] from cardiac leads that were clinically implanted for up to five years were characterized using visual inspection, SEM, ATR-FTIR, GPC, and tensile testing. Surface cracking was not observed in OPT or silicone samples. Shallow cracking was observed in 17/41 (41%) explanted P55D samples. ATR-FTIR indicated minor surface oxidation in some OPT and P55D samples. OPT molecular weight decreased modestly (∼20%) at 2-3 years before stabilizing at 4-5 years. OPT tensile strength decreased modestly (∼25%) at 2-3 years before stabilizing at 4-5 years. OPT elongation at 4-5 years was unchanged from controls. P55D had no significant changes in molecular weight or tensile properties. Overall, results for OPT and P55D were consistent with and limited to cosmetic surface oxidation. Silicone demonstrated excellent biostability with no identifiable degradation. This study of explanted cardiac leads revealed that OPT, P55D, and silicone elastomer demonstrate similar and excellent biostability through five years of implantation in human patients. © 2015 Wiley Periodicals, Inc.

  19. Development and suitability of in vitro digestion models in assessing bioaccessibility of lead from toy matrices

    NARCIS (Netherlands)

    Oomen AG; Twillert K van; Hofhuis MFA; Rompelberg CJM; Versantvoort CHM; SIR; ARO

    2003-01-01

    Children can be orally exposed to compounds by chewing, sucking and ingestion of toy (parts). Only the fraction of contaminant that is released from the toy can reach the blood stream (internal exposure) and can contribute to toxicity. In present risk assessment the release of contaminants from toy

  20. Symposium on intermediate-range atmospheric-transport processes and technology assessment. [Lead Abstract

    Energy Technology Data Exchange (ETDEWEB)

    1981-10-01

    Separate abstracts were prepared for the 47 papers in this proceedings. The purpose of this meeting was to assess the state of the art of modeling atmospheric transport processes 10 to 100 km downwind of point and area sources of pollution. (KRM)

  1. 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.

  2. Lead-Time Bias and Interhospital Transfer after Injury: Trauma Center Admission Vital Signs Underpredict Mortality in Transferred Trauma Patients.

    Science.gov (United States)

    Holena, Daniel N; Wiebe, Douglas J; Carr, Brendan G; Hsu, Jesse Y; Sperry, Jason L; Peitzman, Andrew B; Reilly, Patrick M

    2017-03-01

    Admission physiology predicts mortality after injury, but may be improved by resuscitation before transfer. This phenomenon, which has been termed lead-time bias, may lead to underprediction of mortality in transferred patients and inaccurate benchmarking in centers receiving large numbers of transfer patients. We sought to determine the impact of using vital signs on arrival at the referring center vs on arrival at the trauma center in mortality prediction models for transferred trauma patients. We performed a retrospective cohort study using a state-wide trauma registry including all patients age 16 years or older, with Abbreviated Injury Scale scores ≥ 3, admitted to level I and II trauma centers in Pennsylvania, from 2011 to 2014. The primary outcomes measure was the risk-adjusted association between mortality and interhospital transfer (IHT) when adjusting for physiology (as measured by Revised Trauma Score [RTS]) using the referring hospital arrival vital signs (model 1) compared with trauma center arrival vital signs (model 2). After adjusting for patient and injury factors, IHT was associated with reduced mortality (odds ratio [OR] 0.85; 95% CI 0.77 to 0.93) using the RTS from trauma center admission, but with increased mortality (OR 1.15; 95% CI 1.05 to 1.27) using RTS from the referring hospital. The greater the number of transfer patients seen by a center, the greater the difference in center-level mortality predicted by the 2 models (β -0.044; 95% CI -0.044 to -0.0043; p ≤ 0.001). Trauma center vital signs underestimate mortality in transfer patients and may lead to incorrect estimates of expected mortality. Where possible, benchmarking efforts should use referring hospital vital signs to risk-adjust IHT patients. Copyright © 2016 American College of Surgeons. Published by Elsevier Inc. All rights reserved.

  3. Comparison of occupational exposure assessment methods in a case-control study of lead, genetic susceptibility and risk of adult brain tumors

    Science.gov (United States)

    Bhatti, Parveen; Stewart, Patricia A.; Linet, Martha S.; Blair, Aaron; Inskip, Peter D.; Rajaraman, Preetha

    2013-01-01

    Objectives There is great interest in evaluating gene-environment interactions with chemical exposures, but exposure assessment poses a unique challenge in case-control studies. Expert assessment of detailed work history data is usually considered the best approach, but it is a laborious and time-consuming process. We set out to determine if a less intensive method of exposure assessment (a job exposure matrix [JEM]) would produce similar results to a previous analysis that found evidence of effect modification between expert assessed-lead exposure and risk of brain tumors by a single nucleotide polymorphism in the ALAD gene (rs1800435). Methods We used data from a study of 355 patients with glioma, 151 patients with meningioma and 505 controls. Logistic regression models were used to examine associations between brain tumor risk and lead exposure and effect modification by genotype. We evaluated Cohen’s kappa, sensitivity and specificity for the JEM compared to the expert-assessed exposure metrics. Results Although effect estimates were imprecise and driven by a small number of cases, we found evidence of effect modification between lead exposure and ALAD genotype when using expert- but not JEM-derived lead exposure estimates. Kappa values indicated only modest agreement (exposure metrics, with the JEM indicating high specificity (~0.9) but poor sensitivity (~0.5). Disagreement between the two methods was generally due to having additional information in the detailed work history. Conclusion These results provide preliminary evidence suggesting that high quality exposure data are likely to improve the ability to detect genetic effect modification. PMID:20798009

  4. Considering time in LCA: dynamic LCA and its application to global warming impact assessments.

    Science.gov (United States)

    Levasseur, Annie; Lesage, Pascal; Margni, Manuele; Deschênes, Louise; Samson, Réjean

    2010-04-15

    The lack of temporal information is an important limitation of life cycle assessment (LCA). A dynamic LCA approach is proposed to improve the accuracy of LCA by addressing the inconsistency of temporal assessment. This approach consists of first computing a dynamic life cycle inventory (LCI), considering the temporal profile of emissions. Then, time-dependent characterization factors are calculated to assess the dynamic LCI in real-time impact scores for any given time horizon. Although generally applicable to any impact category, this approach is developed here for global warming, based on the radiative forcing concept. This case study demonstrates that the use of global warming potentials for a given time horizon to characterize greenhouse gas emissions leads to an inconsistency between the time frame chosen for the analysis and the time period covered by the LCA results. Dynamic LCA is applied to the US EPA LCA on renewable fuels, which compares the life cycle greenhouse gas emissions of different biofuels with fossil fuels including land-use change emissions. The comparison of the results obtained with both traditional and dynamic LCA approaches shows that the difference can be important enough to change the conclusions on whether or not a biofuel meets some given global warming reduction targets.

  5. Assessing Idaho Rural Family Physician Scope of Practice Over Time.

    Science.gov (United States)

    Schmitz, David; Baker, Ed; MacKenzie, Lisa; Kinney, Logan; Epperly, Ted

    2015-01-01

    An important consideration determining health outcomes is to have an adequate supply of physicians to address the health needs of the community. The purpose of this investigation was to assess scope of practice factors for Idaho rural family physicians in 2012 and to compare these results to findings from a 2007 study. The target population in this study was rural family physicians in Idaho counties with populations of fewer than 50,000. Identical surveys and methods were utilized in both 2007 and 2012. The physician survey was mailed to 252 rural physicians and was returned by 89 for a response rate of 35.3%. Parametric and nonparametric statistical analyses were conducted to analyze the 2012 results and to assess changes in scope of practice across the time periods. The percentage of rural family physicians in Idaho in 2012 who provided prenatal care, vaginal deliveries, and nursing home care was significantly lower than the results from the 2007 survey. Female physicians were more likely to provide prenatal care and vaginal deliveries than males in 2012. Male physicians were more likely to provide emergency room coverage and esophagogastroduodenoscopy or colonoscopy services than females in 2012. Younger physicians were found to be more likely to provide inpatient admissions and mental health services in 2012 than older physicians. Employed physicians were more likely to provide cesarean delivery, other operating room services and emergency room coverage in 2012 than nonemployed physicians. Further research is needed to assess the root causes of these changes. © 2015 National Rural Health Association.

  6. 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.

  7. 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.

  8. Testing the critical exponent in the relation between stress drop of earthquake and lead time of seismic electric signal

    Directory of Open Access Journals (Sweden)

    E. Dologlou

    2012-08-01

    Full Text Available The application of new data in the power law relation between the stress drop of the earthquake and the lead time of the precursory seismic electric signal led to an exponent which falls in the range of the values of critical exponents for fracture and it is in excellent agreement with a previous one found by (Dologlou, 2012. In addition, this exponent is very close to the one reported by Varotsos and Alexopoulos (1984a, which interconnects the amplitude of the precursory seismic electric signals (SES and the magnitude of the impending earthquake. Hence, the hypothesis that underlying dynamic processes evolving to criticality prevail in the pre-focal area when the SES is emitted is significantly supported.

  9. 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.

  10. Urban geochemistry of lead in gardens, playgrounds and schoolyards of Lisbon, Portugal: assessing exposure and risk to human health

    OpenAIRE

    Reis,A.P.; Patinha, C.; Wragg, J.; Dias, A.C.; Cave, M.; Sousa, A.J.; BATISTA, M. J.; Prazeres, C; Costa, C.; Ferreira da Silva, E.; Rocha, F.

    2014-01-01

    To assess the impact of potentially harmful elements in soil/dust on the health of children that use urban recreational areas to play outdoors, an urban survey of Lisbon, the largest city in Portugal was carried out, collecting soils and dusts from public gardens, parks, playgrounds and schoolyards. An exposure and risk assessment study for the incidental soil/dust ingestion of lead was carried out based on US EPA guidelines using a sub-set of 19 topsoil and 8 outdoor dusts, out o...

  11. Long-term stability and risk assessment of lead in mill waste treated by soluble phosphate.

    Science.gov (United States)

    Tang, Xi; Yang, John

    2012-11-01

    In an effort to address public concerns of the long-term stability and ecological risk reduction of phosphate (P)-stabilized lead (Pb) in mine wastes, mill tailings located at the Jasper County Superfund Site of southwest Missouri, containing ~4000 mg Pb kg(-1), were treated in situ by phosphoric acid at three rates: 0; 7.5; and 10.0 g P kg(-1) soil. Field experiment consisted of 2- by 4-m plots arranged in a randomized complete block design with four replicates of each P level. Soil and plant samples were collected at a 3-month interval during five to six (5-6) years post treatments and analyzed for Pb bioaccessibility and leachability, microbial toxicity, Pb chemical fraction, and elemental composition of Pb solids, and Pb concentration in plant tissue. Results indicated that the P treatments significantly reduced bioaccessible and leachable Pb in the mill waste, and the reductions were maintained during the sampling period. Lead concentration in plant tissue was positively related to the Pb bioaccessibility. There was no significant toxicological effect of the treatments on soil microbial community. The treatment using 10 g P kg(-1) appeared to be most effective for overall risk reduction. The Pb stabilization and risk reduction by the P treatments were accomplished by the induced transformation of labile Pb species to relatively insoluble forms, probably pyromorphite-like minerals. This study illustrated that in situ Pb stabilization by soluble phosphate would be long-term and ecologically-safe, which could safeguard human health and ecosystem from Pb contamination in mining areas. Copyright © 2012 Elsevier B.V. All rights reserved.

  12. Iron, manganese, and lead at Hawaii Ocean Time-series station ALOHA: Temporal variability and an intermediate water hydrothermal plume

    Energy Technology Data Exchange (ETDEWEB)

    Boyle, E.A.; Bergquist, B.A.; Kayser, R.A.; Mahowald, N. [MIT, Cambridge, MA (US)

    2005-02-15

    Trace metal clean techniques were used to sample Hawaii Ocean Time-series (HOT) station ALOHA on seven occasions between November 1998 and October 2002. On three occasions, full water column profile samples were obtained; on the other four occasions, surface and near-surface euphotic zone profiles were obtained. Low Fe concentrations (< 0.1 nmol kg{sup -1}) are seen in the lower euphotic zone, and Fe concentrations increase to a maximum in intermediate waters. In the deepwaters (> 2500 m), the concentrations we observe (0.4-0.5 nmol kg{sup -1}) are significantly lower than some other deep North Pacific stations but are similar to values that have been reported for a station 350 miles to the northeast. We attribute these low deepwater values to transport of low-Fe Antarctic Bottom Water into the basin and a balance between Fe regeneration and scavenging in the deep water. Near-surface waters have higher Fe levels than observed in the lower euphotic zone. Significant temporal variability is seen in near-surface Fe concentrations (ranging from 0.2-0.7 nmol kg{sup -1}); we attribute these surface Fe fluctuations to variable dust deposition, biological uptake, and changes in the mixed layer depth. This variability could occur only if the surface layer Fe residence time is less than a few, years, and based on that constraint, it appears that a higher percentage of the total Fe must be released from North Pacific aerosols compared to North Atlantic aerosols. We attribute the surface water Pb decrease to the elimination of leaded gasoline in Japan and to some extent by the U.S. and Canada. We attribute most of the remaining Pb in Pacific surface waters to Asian emissions, more likely due to high-temperature industrial activities such as coal burning rather than to leaded gasoline consumption.

  13. 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.

  14. 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.

  15. 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.

  16. 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.

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

    Directory of Open Access Journals (Sweden)

    Farida El Baz Mohamed

    2015-01-01

    Full Text Available Background and Aims. 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. Methods. 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. Results. 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. Conclusion. 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.

  18. 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.

  19. 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 α2-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.

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

    Energy Technology Data Exchange (ETDEWEB)

    Ellingwood, B.R. [Johns Hopkins Univ., Baltimore, MD (United States)

    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.

  1. 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.

  2. 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%, p<0.001). When using ECG stress testing for evaluation of patients with suspected myocardial ischemia, the diagnostic accuracy of ST-deviations is highest when evaluated at +80ms after the J-point, and at 2min into recovery. Copyright © 2017 Elsevier B.V. All rights reserved.

  3. Operator Radiation and the Efficacy of Ceiling-Suspended Lead Screen Shielding during Coronary Angiography: An Anthropomorphic Phantom Study Using Real-Time Dosimeters

    Science.gov (United States)

    Jia, Qianjun; Chen, Ziman; Jiang, Xianxian; Zhao, Zhenjun; Huang, Meiping; Li, Jiahua; Zhuang, Jian; Liu, Xiaoqing; Hu, Tianyu; Liang, Wensheng

    2017-02-01

    Operator radiation and the radiation protection efficacy of a ceiling-suspended lead screen were assessed during coronary angiography (CA) in a catheterization laboratory. An anthropomorphic phantom was placed under the X-ray beam to simulate patient attenuation in eight CA projections. Using real-time dosimeters, radiation dose rates were measured on models mimicking a primary operator (PO) and an assistant. Subsequently, a ceiling-suspended lead screen was placed in three commonly used positions to compare the radiation protection efficacy. The radiation exposure to the PO was 2.3 to 227.9 (mean: 67.2 ± 49.0) μSv/min, with the left anterior oblique (LAO) 45°/cranial 25° and cranial 25° projections causing the highest and the lowest dose rates, respectively. The assistant experienced significantly less radiation overall (mean: 20.1 ± 19.6 μSv/min, P RAO) 30° and cranial 25° projections resulting in the highest and lowest exposure levels, respectively. Combined with table-side shielding, the ceiling-suspended lead screen reduced the radiation to the PO by 76.8%, 81.9% and 93.5% when placed close to the patient phantom, at the left side and close to the PO, respectively, and reduced the radiation to the assistant by 70.3%, 76.7% and 90.0%, respectively. When placed close to the PO, a ceiling-suspended lead screen provides substantial radiation protection during CA.

  4. Assessment of toxic metal exposure following the Camelford water pollution incident: evidence of acute mobilization of lead into drinking water.

    Science.gov (United States)

    Powell, J J; Greenfield, S M; Thompson, R P; Cargnello, J A; Kendall, M D; Landsberg, J P; Watt, F; Delves, H T; House, I

    1995-03-01

    Following the incident of acidic pollution of water by aluminium sulfate centred around Camelford in July 1988, we have carried out a retrospective analysis of the mobilization of toxic metals to residents of the area. An advanced nuclear technique was used to measure trace levels of elements within hair, thus, avoiding surface contamination. In contrast to controls, lead, but no other toxic metals, was consistently found within sections of hair that dated to mid-1988 from four residents; they must, therefore, have consumed this metal around the time of the incident. The source of this lead was probably local water pipe residue, and this was found on analysis to have a matrix specific to such soft-water areas that, prior to the incident, had slowly accumulated certain toxic metals such as cadmium and uranium and particularly lead. Lead is mobilized from such residues by acidic water and could, therefore, have heavily contaminated mains water after the incident. However, analyses of residents' plasma and whole blood, and of urine following a lead-chelation test, showed no evidence of either long-term increased body burdens of toxic metals or depletion of essential elements. In addition, we found no evidence of continued poor water quality in the area. In conclusion, during a short period following the pollution, some residents who consumed mains water would have been acutely exposed to lead and other toxic metals. Prediction of the scale of metal exposure to individuals was not possible owing to heterogeneity of the water distribution network, but long-term effects to residents from lead are not anticipated.(ABSTRACT TRUNCATED AT 250 WORDS)

  5. Screening for Elevated Blood Lead Levels in Children: Assessment of Criteria and a Proposal for New Ones in France.

    Science.gov (United States)

    Etchevers, Anne; Glorennec, Philippe; Le Strat, Yann; Lecoffre, Camille; Bretin, Philippe; Le Tertre, Alain

    2015-12-03

    The decline in children's Blood Lead Levels (BLL) raises questions about the ability of current lead poisoning screening criteria to identify those children most exposed. The objectives of the study were to evaluate the performance of current screening criteria in identifying children with blood lead levels higher than 50 µg/L in France, and to propose new criteria. Data from a national French survey, conducted among 3831 children aged 6 months to 6 years in 2008-2009 were used. The sensitivity and specificity of the current criteria in predicting blood lead levels higher than or equal to 50 µg/L were evaluated. Two predictive models of BLL above 44 µg/L (for lack of sufficient sample size at 50 µg/L) were built: the first using current criteria, and the second using newly identified risk factors. For each model, performance was studied by calculating the area under the ROC (Receiver Operating Characteristic) curve. The sensitivity of current criteria for detecting BLL higher than or equal to 50 µg/L was 0.51 (0.26; 0.75) and specificity was 0.66 (0.62; 0.70). The new model included the following criteria: foreign child newly arrived in France, mother born abroad, consumption of tap water in the presence of lead pipes, pre-1949 housing, period of construction of housing unknown, presence of peeling paint, parental smoking at home, occupancy rates for housing and child's address in a cadastral municipality or census block comprising more than 6% of housing that is potentially unfit and built pre-1949. The area under the ROC curve was 0.86 for the new model, versus 0.76 for the current one. The lead poisoning screening criteria should be updated. The risk of industrial, occupational and hobby-related exposure could not be assessed in this study, but should be kept as screening criteria.

  6. Screening for Elevated Blood Lead Levels in Children: Assessment of Criteria and a Proposal for New Ones in France

    Directory of Open Access Journals (Sweden)

    Anne Etchevers

    2015-12-01

    Full Text Available The decline in children’s Blood Lead Levels (BLL raises questions about the ability of current lead poisoning screening criteria to identify those children most exposed. The objectives of the study were to evaluate the performance of current screening criteria in identifying children with blood lead levels higher than 50 µg/L in France, and to propose new criteria. Data from a national French survey, conducted among 3831 children aged 6 months to 6 years in 2008–2009 were used. The sensitivity and specificity of the current criteria in predicting blood lead levels higher than or equal to 50 µg/L were evaluated. Two predictive models of BLL above 44 µg/L (for lack of sufficient sample size at 50 µg/L were built: the first using current criteria, and the second using newly identified risk factors. For each model, performance was studied by calculating the area under the ROC (Receiver Operating Characteristic curve. The sensitivity of current criteria for detecting BLL higher than or equal to 50 µg/L was 0.51 (0.26; 0.75 and specificity was 0.66 (0.62; 0.70. The new model included the following criteria: foreign child newly arrived in France, mother born abroad, consumption of tap water in the presence of lead pipes, pre-1949 housing, period of construction of housing unknown, presence of peeling paint, parental smoking at home, occupancy rates for housing and child’s address in a cadastral municipality or census block comprising more than 6% of housing that is potentially unfit and built pre-1949. The area under the ROC curve was 0.86 for the new model, versus 0.76 for the current one. The lead poisoning screening criteria should be updated. The risk of industrial, occupational and hobby-related exposure could not be assessed in this study, but should be kept as screening criteria.

  7. Assessing computerized eye tracking technology for gaining insight into expert interpretation of the 12-lead electrocardiogram: an objective quantitative approach.

    Science.gov (United States)

    Bond, R R; Zhu, T; Finlay, D D; Drew, B; Kligfield, P D; Guldenring, D; Breen, C; Gallagher, A G; Daly, M J; Clifford, G D

    2014-01-01

    ), the rhythm strip (3.47s), II (2.74s), V3 (2.63s), I (2.53s), aVL (2.45s), V5 (2.27s), aVF (1.74s), aVR (1.63s), V6 (1.39s), III (1.32s) and V4 (1.19s). It was also found that on average the annotator spends an equal amount of time studying leads in the frontal plane (15.89s) when compared to leads in the transverse plane (15.70s). It was found that on average the annotators fixated on lead I first followed by leads V2, aVL, V1, II, aVR, V3, rhythm strip, III, aVF, V5, V4 and V6. We found a strong correlation (r=0.67) between time to first fixation on a lead and the total fixation duration on each lead. This indicates that leads studied first are studied the longest. There was a weak negative correlation between duration and accuracy (r=-0.2) and a strong correlation between age and accuracy (r=0.67). Eye tracking facilitated a deeper insight into how expert annotators interpret the 12-lead ECG. As a result, the authors recommend ECG annotators to adopt an initial first impression/pattern recognition approach followed by a conventional systematic protocol to ECG interpretation. This recommendation is based on observing misdiagnoses given due to first impression only. In summary, this research presents eye gaze results from expert ECG annotators and provides scope for future work that involves exploiting computerized eye tracking technology to further the science of ECG interpretation. Copyright © 2014 Elsevier Inc. All rights reserved.

  8. A neuropsychological study of children with elevated dentine lead level: Assessment of the effect of lead in different socio-economic groups

    Energy Technology Data Exchange (ETDEWEB)

    Hansen, O.N.; Trillingsgaard, A.; Beese, I.; Lyngbye, T.; Grandjean, P. (Univ. of Aarhus (Denmark))

    1989-05-01

    The study was carried out in the municipality of Aarhus, a city of 250,000 inhabitants. The study was designed as a cross-sectional cohort study of school children in first grade in 1982-83. A total of 2,412 children were contacted and asked to submit their shed teeth to the teacher, and 1,291 children delivered at least one usable tooth (response rate, 54 percent). The lead level in circumpulpal dentin showed an average of 10.7 micrograms/g. Eight percent of the children (N = 110) had a lead level above 18.7 micrograms/g and were selected as a high lead exposure group. This group was matched by sex and socio-economic status of the parents with control children with a dentin lead level below 5 micrograms/g. Following a detailed interview with the parents, children were excluded from the study if medical risk factors were present. A clinical psychologist, blind to the lead data, administered selected psychometric tests to 162 of the children selected. The high-lead children scored lower on the WISC when compared to low-lead children, especially on the Verbal IQ (p less than 0.001) and Full Scale IQ (p less than 0.01). No significant difference was seen between the high- and low-exposure groups on the Performance IQ and on several experimental tests. Impaired function associated with lead exposure was also found on the Bender Visual Motor Gestalt Test (p less than 0.001) and on a behavioral rating scale (p less than 0.01). These results remained statistically significant even after controlling for socio-economic status and other confounding variables.

  9. 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.

  10. Compliance to a Cell Phone-Based Ecological Momentary Assessment Study: The Effect of Time and Personality Characteristics

    Science.gov (United States)

    Courvoisier, Delphine S.; Eid, Michael; Lischetzke, Tanja

    2012-01-01

    Ecological momentary assessment (EMA) is a method that is now widely used to study behavior and mood in the settings in which they naturally occur. It maximizes ecological validity and avoids the limitations of retrospective self-reports. Compliance patterns across time have not been studied. Consistent compliance patterns could lead to data not…

  11. Neglect of lactation stage leads to naive assessment of residual feed intake in dairy cattle.

    Science.gov (United States)

    Li, B; Berglund, B; Fikse, W F; Lassen, J; Lidauer, M H; Mäntysaari, P; Løvendahl, P

    2017-11-01

    models, RFI was genetically different over lactation, especially between early and later lactation stages. Genetic correlation estimates for RFI between early and later lactation tended to be higher when using model [2] compared with model [1]. In conclusion, partial regression coefficients of DMI on energy sinks differed across lactation when modeling RFI. Neglect of lactation stage when defining RFI could affect the assessment of RFI and the estimation of genetic parameters for RFI across lactation. Copyright © 2017 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  12. 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)

  13. 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.

  14. Real time monitoring of spot-welded joints under service load using lead zirconate titanate (PZT) transducers

    Science.gov (United States)

    Yao, Ping; Zheng, Botong; Dawood, Mina; Huo, Linsheng; Song, Gangbing

    2017-03-01

    This paper proposes a nondestructive method to evaluate the health status of resistance spot-welded (RSW) joint under service load using lead zirconate titanate (PZT) active sensing system, in which the PZT transducers were used as both actuator and sensor. The physical principle of the approach was validated through a numerical analysis showing that an opening between the faying faces at the welded joint occurred under tension load. The opening decreased the contact area hence reduced the amplitude of the stress wave received by the PZT sensor. Therefore, by comparing the energy index of the signals before and after the loading, the health condition of the joint can be evaluated. Five ST14 steel single lap joint specimens were tested under tension load while being monitored by the PZT sensing system and digital image correlation (DIC) system in real time. The data obtained from the DIC system validated the numerical results. By comparing the energy index of the signal obtained from the PZT sensing system before and after unloading, it was concluded that the RSW joint was intact after being loaded to the service load. The proposed method is promising in evaluating the health condition of RSW joint nondestructively.

  15. Enhancing Resilience to Heat Extremes: Multi-model Forecasting of Excessive Heat Events at Subseasonal Lead Times

    Science.gov (United States)

    Vintzileos, A.; Halpert, M.; Gottschalk, J.; Allgood, A.

    2016-12-01

    Heatwaves are among the most dangerous, yet invisible, of natural hazards. According to NOAA, the distribution of 30-year based annual mean fatalities from natural hazards in the U.S. ranks as follows; those from heat (130), floods (81), tornadoes (70), lightning (48) and hurricanes (46). Early warning to excessive heat events can be improved by using multi-scale prognostic systems. We designed and developed such a system for forecasting excessive heat events at lead times beyond Week-1. This Subseasonal Excessive Heat Outlook System (SEHOS) consists of (a) a monitoring/verification component and (b) a forecasting component which in its baseline version uses NOAA's Global Ensemble Forecast System (GEFS) predictions of temperature and humidity from Day-8 to Day-14. In this presentation, we discuss the definition of heat events, sources of predictability and present the forecast skill of SEHOS for the GEFS reforecast period (1985-2014). We then use subseasonal reforecasts from several models from the S2S database and discuss the forecast value added by multi-model approaches in predicting excessive heat events.

  16. Jasmonic acid deficiency leads to scattered floret opening time in cytoplasmic male sterile rice Zhenshan 97A.

    Science.gov (United States)

    Liu, Li; Zou, Zhengshan; Qian, Ke; Xia, Chan; He, Ying; Zeng, Hanlai; Zhou, Xie; Riemann, Michael; Yin, Changxi

    2017-07-20

    Cytoplasmic male sterile (CMS) rice has been widely used for hybrid rice seed production in China. However, CMS rice suffers from undesirable flowering habits including scattered floret opening time (FOT), which causes different FOTs among parental rice plants and greatly reduces hybrid rice seed production. Little is known about the mechanism of scattered FOT in CMS rice. Our results demonstrate that scattered FOT in CMS rice Zhenshan 97A (ZS97A) resulted from the lack of a driving force to open florets, which was directly caused by retarded lodicule expansion. Our results indicate that retarded lodicule expansion in ZS97A was caused by reduced water accumulation due to retarded accumulation of osmotic regulation substances (ORSs). Further, the retardation in accumulation of ORSs and water were caused by jasmonic acid (JA) deficiency, resulting from down-regulation of OsAOC expression. Applying JA restored scattered FOT in ZS97A by promoting ORS and water accumulation, and inducing the expansion of the lodicules. Taken together, JA deficiency inhibited lodicule expansion by retarding the accumulation of ORSs and water, leading to scattered FOT in CMS rice ZS97A. © The Author 2017. Published by Oxford University Press on behalf of the Society for Experimental Biology.

  17. 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 stress scores (p 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.

  18. 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, E-mail: zjcdcwxf@gmail.com [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.

  19. A Thailand case study based on quantitative assessment: does a national lead agency make a difference in pre-hospital care development in middle income countries?

    Science.gov (United States)

    Suriyawongpaisal, Paibul; Aekplakorn, Wichai; Tansirisithikul, Rassamee

    2014-12-12

    Emergency Medical Institute of Thailand (EMIT) has been established as a national lead agency to improve emergency medical service systems since December 2008. However up to now, there has not been any published systematic assessment of its performance to guide further policy decisions. This study assesses the 4-year pre-hospital care coverage and performance in Thailand after EMIT establishment. The assessment makes use of 1,171,564 records from a national data set for pre-hospital care i.e., Information Technology for Emergency Medical Service System (ITEMS) in 2012. Comparing with historical data, we found evidence indicating the national lead agency making differences in two basic requirements of pre-hospital care i.e., the coverage was increased by at least 1.4 times higher than the majority reported figures among 11 out of the total 13 regions of the country at baseline; and mean total response time for critical-coded patients, the longest in our study, is 1.6 times shorter than previously reported figure in 2008 (48.46 minutes). Analysis of the national data set also revealed quite substantial missing values indicating a need for further improvement. When historical data was not available, we compared our findings with international figures. Over triage rate of 28.4% for advanced life support (ALS) ambulance was found which is roughly a third of that reported in Taiwan. Almost all patients were stabilized and/or treated regardless of being transferred to hospitals in contrast to the scenarios in the U.S. systems which may probably be due to different payment mechanism. Relying on circumstantial evidences, we identified probable stagnation in pre-hospital care coverage for patients visiting emergency department after the establishment of the lead agency. This national data assessment shows progression in certain basic pre-hospital care requirements in Thailand. However, it needs regular systematic evaluation and there is still room for improvement of pre

  20. Reference Gene Selection for Quantitative Real-Time RT-PCR Normalization in Iris. lactea var. chinensis Roots under Cadmium, Lead, and Salt Stress Conditions

    Directory of Open Access Journals (Sweden)

    Chun-Sun Gu

    2014-01-01

    Full Text Available Quantitative real time PCR (RT-qPCR has emerged as an accurate and sensitive method to measure the gene expression. However, obtaining reliable result depends on the selection of reference genes which normalize differences among samples. In this study, we assessed the expression stability of seven reference genes, namely, ubiquitin-protein ligase UBC9 (UBC, tubulin alpha-5 (TUBLIN, eukaryotic translation initiation factor (EIF-5A, translation elongation factor EF1A (EF1α, translation elongation factor EF1B (EF1b, actin11 (ACTIN, and histone H3 (HIS, in Iris. lactea var. chinensis (I. lactea var. chinensis root when the plants were subjected to cadmium (Cd, lead (Pb, and salt stress conditions. All seven reference genes showed a relatively wide range of threshold cycles (Ct values in different samples. GeNorm and NormFinder algorithms were used to assess the suitable reference genes. The results from the two software units showed that EIF-5A and UBC were the most stable reference genes across all of the tested samples, while TUBLIN was unsuitable as internal controls. I. lactea var. chinensis is tolerant to Cd, Pb, and salt. Our results will benefit future research on gene expression in response to the three abiotic stresses.

  1. Assessment of Four Heavy Metals Mercury, Lead, Copper and Cadmium Levels in Muscles of Import-ed Tilapia to Iran

    Directory of Open Access Journals (Sweden)

    Behsan Hemmatinezhad

    2017-04-01

    Full Text Available This study was conducted to determine the residues of mercury (Hg, lead (Pb, copper (Cu and cadmium (Cd in the imported tilapia fillets. Thirty random samples from imported tilapia fillets were collected from different markets in Isfahan City, central Iran. They were analyzed using Graphite Furnace Atomic Absorption Spectrometer (Perkin Elmer 800 for Pb, Cu, Cd and flow injection mercury system (Perkin Elmer 400 for Hg. Out of the 30 tested samples, concentration of Hg, Pb, Cu and Cd in the tilapia fillets samples as mean± standard deviation were 0.083±.016, 0.638±0.067, 0.521± 0.081 and 0.136 ± 0.025 mg/kg, respectively. Among these, amounts obtained for all metals except for lead were lower than the permissible level specified by WHO (P<1%. The Pb concentrations in all examined samples were higher than WHO standards. The continuous consumption of these contaminated fish regularly for long time may lead to health troubles.

  2. Relationships among assessment time, time on task, and motor skill performance in children with autism spectrum disorder.

    Science.gov (United States)

    Breslin, Casey M; Rudisill, Mary E

    2013-10-01

    Twenty-two children (age range of 3.5-10.92 years old) with autism spectrum disorder (ASD) were assessed using the Test of Gross Motor Development (Second Edition; TGMD-2) using three different protocols. The total duration of assessment time and the percentage of time engaged in on-task behavior during the assessments were measured and analyzed using within-subjects repeated measure ANOVA designs to compare performance across the three protocols. Significant differences emerged across the duration of assessment time by assessment protocol, while no significant differences emerged for time on-task during the assessments by protocol used. In addition, correlations were calculated between the TGMD-2 scores and the duration of assessment time and the percentage of time on-task. An inverse relationship was found between TGMD-2 scores and total duration of assessment time by protocol used, (r = .726, .575, .686), while a positive relationship was found between the TGMD-2 scores and time on-task (r = -.570, -.535, -.798). These results suggest a direct relationship between skill proficiency and contextually appropriate behaviors.

  3. Influence of compost addition on lead and arsenic bioavailability in reclaimed orchard soil assessed using Porcellio scaber bioaccumulation test

    Science.gov (United States)

    Udovic, M.; McBride, M.B.

    2015-01-01

    A long history of lead arsenate application in orchards has led to significant accumulation of Pb and As in the topsoil. Besides the threat that such soils represent for the environment, reclamation of old orchards for agricultural purposes implies the exposure of humans to Pb and As. In this study we assessed the influence of vegetable compost addition (as a sustainable agricultural practice) to contaminated acidic orchard soil on Pb and As bioavailability, assessed with two selective non-exhaustive chemical extractions and with an in vivo bioaccumulation test with an isopod (P. scaber). The treatment with compost caused a significant increase in soil pH and total carbon content, resulting in a consistent decrease of Pb bioavailability. In contrast, the bioavailability of As increased, indicating that a complementary treatment should be used for reducing the bioavailability of As in old orchard soils. This is the first report on the use of As accumulation in P. scaber as a tool for the assessment of As bioavailability in contaminated orchard soil. PMID:22240057

  4. 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.

  5. Prediction of outcome after subarachnoid hemorrhage : Timing of clinical assessment

    NARCIS (Netherlands)

    van Donkelaar, Carlina E.; Bakker, Nicolaas A.; Veeger, Nic J. G. M.; Uyttenboogaart, Maarten; Metzemaekers, Jan D. M.; Eshghi, Omid S.; Mazuri, Aryan; Foumani, Mahrouz; Luijckx, Gert-Jan; Groen, Rob J. M.; van Dijk, J. Marc C.

    OBJECTIVE Currently, early prediction of outcome after spontaneous subarachnoid hemorrhage (SAH) lacks accuracy despite multiple studies addressing this issue. The clinical condition of the patient on admission as assessed using the World Federation of Neurosurgical Societies (WFNS) grading scale is

  6. Comparative assessment of aluminum and lead concentrations in serum and tissue bioptates in patients with laryngeal papilloma or cancer.

    Science.gov (United States)

    Olszewski, J; Latusiński, J; Kita, A; Pietkiewicz, P; Starostecka, Beata; Majak, J

    2006-01-01

    A comparative assessment of toxic element concentrations in serum and tissue bioptates in patients with laryngeal papilloma or cancer was performed. Examinations were conducted in 60 patients (40 men and 20 women) aged 20-88 years (average 59 +/- 05). Patients were divided into 3 groups; 20 patients with laryngeal papilloma were in group I, 20 with laryngeal cancer were in group II, and 20 with deviated nasal septums were included as a control group (III). Diagnosis of laryngeal papilloma (removed by direct microlaryngoscopy--Kleinsasser method) and laryngeal cancer (removed by the Rethi method) was histopatologically confirmed in patients from groups I and II, respectively. Patients in the control group received functional surgery to repair deviated nasal septums. Serum and tissue samples were obtained from all patients before surgery. Aluminum and lead concentrations were analysed by inductively coupled plasma atomic emission spectrometry (ICP-AES) using a Spectroflame M spectrometer. The considerable rise of aluminum and lead concentration in tissue bioptates and aluminum in serum in groups I and II in comparison to the control group suggests that these elements may play a significant part in the aetiology and development of precancerous lesions and laryngeal cancers. Measuring toxic chemical element concentrations in tissue bioptates can be useful in the diagnosis and estimation of development of precancerous lesions of the larynx as well as laryngeal cancer. Toxic elements concentration may play a significant role in carcinogenesis and may determine trends in cancer aetiology.

  7. 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.

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

    Science.gov (United States)

    Furferi, Rocco; Governi, Lapo; Volpe, Yary; Carfagni, Monica

    2016-08-31

    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.

  9. 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.

  10. [The applicable study of two models used in the assessment of long-term exposure to food lead].

    Science.gov (United States)

    Jin, Ying-liang; Zhang, Ya-fei; Liu, Pei

    2013-07-01

    To compare the results of observed individual means (OIM) model with beta binomial-normal (BBN) model and to apply the two models to assessment of long-term dietary lead exposure. Food consumption data were obtained from the National Nutrition and Health Survey conducted in 2002 by 24-hour recall method. Contamination data were derived from the national food contamination monitoring program from 2000 to 2006 and from monitoring data of Customs exports for agricultural products between 2005 and 2006. By multiplying the average consumption of food with the average concentration of contaminant, the OIM model calculated dietary intake per day. By correcting the within-person variation and keeping the between-person variation, the BBN model built dietary intake in the long-term.Using the example of food lead data, the results of two models were compared. The high-end percentile of OIM model was higher than the BBN model in various age groups.In the general population, the dietary intake of OIM model from 25th percentile to 99.9th percentile was between 1.167 and 7.313 µg×kg(-1)×d(-1), and the dietary intake of BBN model with the same percentile range was between 1.193 and 5.729 µg×kg(-1)×d(-1). The median of various groups was similar between the two models. The dietary intakes in the general population of two models were 1.543 and 1.579 µg×kg(-1)×d(-1). The high-end percentile of OIM model is more conservative than BBN model in the long-term dietary exposure assessment.

  11. 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

  12. 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.

  13. 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…

  14. Geochronological and lead-isotope evidences for rapid crust formation in middle-proterozoic time: The Labrador example

    Science.gov (United States)

    Schaerer, Urs

    1988-01-01

    Extensive U-Pb geochronological studies in the Grenville and Makkovik provinces have shown that eastern Labrador is underlain by two distinct crustal blocks. In order to substantiate the juvenile character of the middle-Proterozoic crustal block, the isotopic compositon of lead in leached k-feldspars from the same rocks were analyzed. The results of the analysis are briefly discussed.

  15. Assessment of over time changes of moisture, cyanide and selected ...

    African Journals Online (AJOL)

    sunny

    2014-10-15

    Oct 15, 2014 ... optimum storage time under the conditions was judged to be six months for nutrients and organoleptic parameters stability. Key words: Cassava leaves, solar drying, storage time, Rwanda. INTRODUCTION. Agriculture is a substantial food source for rural and urban populations, and also a reliable source of ...

  16. 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…

  17. 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...

  18. Does Time Matter? Comparing Trajectory Concordance and Covariate Association Using Time-Based and Age-Based Assessments

    Science.gov (United States)

    Piquero, Alex R.; Monahan, Kathryn C.; Glasheen, Cristie; Schubert, Carol A.; Mulvey, Edward P.

    2013-01-01

    Much criminological research has used longitudinal data to assess change in offending over time. An important feature of some data sources is that they contain cross-sections of different aged individuals followed over successive time periods, thereby potentially conflating age and time. This article compares the substantive conclusions about the…

  19. 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....

  20. 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.

  1. 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…

  2. 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...

  3. 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 ...

  4. Assessment of cardiac time intervals using high temporal resolution real-time spiral phase contrast with UNFOLDed-SENSE.

    Science.gov (United States)

    Kowalik, Grzegorz T; Knight, Daniel S; Steeden, Jennifer A; Tann, Oliver; Odille, Freddy; Atkinson, David; Taylor, Andrew; Muthurangu, Vivek

    2015-02-01

    To develop a real-time phase contrast MR sequence with high enough temporal resolution to assess cardiac time intervals. The sequence utilized spiral trajectories with an acquisition strategy that allowed a combination of temporal encoding (Unaliasing by fourier-encoding the overlaps using the temporal dimension; UNFOLD) and parallel imaging (Sensitivity encoding; SENSE) to be used (UNFOLDed-SENSE). An in silico experiment was performed to determine the optimum UNFOLD filter. In vitro experiments were carried out to validate the accuracy of time intervals calculation and peak mean velocity quantification. In addition, 15 healthy volunteers were imaged with the new sequence, and cardiac time intervals were compared to reference standard Doppler echocardiography measures. For comparison, in silico, in vitro, and in vivo experiments were also carried out using sliding window reconstructions. The in vitro experiments demonstrated good agreement between real-time spiral UNFOLDed-SENSE phase contrast MR and the reference standard measurements of velocity and time intervals. The protocol was successfully performed in all volunteers. Subsequent measurement of time intervals produced values in keeping with literature values and good agreement with the gold standard echocardiography. Importantly, the proposed UNFOLDed-SENSE sequence outperformed the sliding window reconstructions. Cardiac time intervals can be successfully assessed with UNFOLDed-SENSE real-time spiral phase contrast. Real-time MR assessment of cardiac time intervals may be beneficial in assessment of patients with cardiac conditions such as diastolic dysfunction. © 2014 Wiley Periodicals, Inc.

  5. 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...

  6. How lethal concentration changes over time : toxicity of cadmium, copper, and lead to the freshwater isopod **Asellus aquaticus**

    OpenAIRE

    Ginneken, van, LPPP Lukas; Blust, Ronny; Bervoets, Lieven

    2017-01-01

    Abstract: Metal pollution is a serious threat to environmental health. While the aquatic isopod Asellus aquaticus L. (Isopoda) is an important decomposer of freshwater ecosystems, very little research has reported its long-term or incipient lethal concentrations for metals. Moreover, the lethal concentrations at a certain percentage (LCxs) that can be found in the literature are often based on unmeasured concentrations, which could lead to a severe underestimation of the actual toxicity. In t...

  7. Análise do lead time nos processos logísticos de uma rede varejista de flores/Analysis of the lead time in the logistics processes of a retail flower network

    National Research Council Canada - National Science Library

    Luciana Torres Correia de Mello; Hugo Carlos Mansano Dornfeld; Givaldo Guilherme dos Santos; Débora Passos; Rafael Ribeiro; Moacir Godinho Filho

    2016-01-01

    .... The collected data related to the operations processing times showed characteristics of logistics processes involved in the distribution of raw material, from its acquisition to delivery at each branch office...

  8. Time Trek: a 13.7 km long nature trail leading through the history of the Universe and the Earth

    Science.gov (United States)

    Lehto, Kirsi; Lehto, Harry J.; Brozinski, Ari; Gardner, Esko; Eklund, Olav; Rajala, Kirsi; Räsänen, Matti; Sääksjärvi, Ilari; Vainio, Laura; Vuorisalo, Timo

    2013-01-01

    With the aim to visualize the span of time since the formation of our Universe we have set up a nature and hiking trail called `Time Trek'. The 13.7 km length of the trail corresponds to the age of the Universe, and portrays its history including events important for Earth and life. One kilometre corresponds to a billion years, and one metre to a million years of time. The trek combines astronomical, physical, geological and biological time lines, and presents a holistic view of the history of time. It helps people to comprehend the causal and temporal connections of different phenomena. To the trekker, it offers a concrete experience of the lengths and proportions of different time periods, which otherwise are very difficult to understand.

  9. Estimation of overdiagnosis using short-term trends and lead time estimates uncontaminated by overdiagnosed cases: Results from the Norwegian Breast Screening Programme.

    Science.gov (United States)

    Michalopoulos, Dimitrios; Duffy, Stephen W

    2016-12-01

    Estimating overdiagnosis in cancer screening is complicated. Using observational data, estimation of the expected incidence in the screening period and taking account of lead time are two major problems. Using data from the Cancer Registry of Norway and the Norwegian Breast Cancer Screening Programme, we estimated incidence trends, using age-specific trends by year in the pre-screening period (1985-95). We also estimated sojourn time and sensitivity using interval cancers only. Thus, lead time estimates were uncontaminated by overdiagnosed cases. Finally, we derived estimates of overdiagnosis separately for all cancers, and for invasive cancers only, correcting for lead time, using two different methods. Our results indicate that overdiagnosis of all cancers, invasive and in situ, constituted 15-17% of all screen-detected cancers in 1996-2009. For invasive cancers only, the corresponding figures were -2 to 7% in the same period, suggesting that a substantial proportion of the overdiagnosis in the Norwegian Programme was due to ductal carcinoma in situ. Using short-term trends, instead of long, prior to screening was more effective in predicting incidence in the screening epoch. In addition, sojourn time estimation using symptomatic cancers only avoids over-correction for lead time and consequently underestimation of overdiagnosis. Longer follow-up will provide more precise estimates of overdiagnosis. © The Author(s) 2016.

  10. Effects of Low Level Lead Exposure on Associative Learning and Memory in the Rat: Influences of Sex and Developmental Timing Of Exposure

    Science.gov (United States)

    Anderson, D.W.; Mettil, W.; Schneider, J.S.

    2016-01-01

    Lead (Pb) exposure during development impairs a variety of cognitive, behavioral and neurochemical processes resulting in deficits in learning, memory, attention, impulsivity and executive function. Numerous studies have attempted to model this effect of Pb in rodents, with the majority of studies focusing on hippocampus-associated spatial learning and memory processes. Using a different paradigm, trace fear conditioning, a process requiring coordinated integration of both the medial prefrontal cortex and the hippocampus, we have assessed the effects of Pb exposure on associative learning and memory. The present study examined both female and male Long Evans rats exposed to three environmentally relevant levels of Pb (150 ppm, 375 ppm and 750 ppm) during different developmental periods: perinatal (PERI; gestation – postnatal day 21), early postnatal (EPN; postnatal days 1–21) and late postnatal (LPN; postnatal days 1–55). Testing began at postnatal day 55 and consisted of a single day of acquisition training, and three post training time points (1, 2 and 10 days) to assess memory consolidation and recall. All animals, regardless of sex, developmental window or level of Pb-exposure, successfully acquired conditioned-unconditioned stimulus association during training. However, there were significant effects of Pb-exposure on consolidation and memory recall at days 1–10 post training. In females, EPN and LPN exposure to 150 ppm Pb (but not PERI exposure) significantly impaired recall. In contrast, only PERI 150 ppm and 750 ppm-exposed males had significant recall deficits. These data suggest a complex interaction between sex, developmental window of exposure and Pb-exposure level on consolidation and recall of associative memories. PMID:26812500

  11. 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.

  12. 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.

  13. 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

    1997-01-01

    Inspection and repair of tower structure and lift, instrument calibration have been done. Wireless data transmission to MIPS (Meteorological Information Processing System) has been done after collection in the DAS where environmental assessment can be done by the developed simulation programs in both cases of normal operation and emergency. Wind direction, wind speed, temperature, humidity at 67m, 27m, and 10m height and temperature, humidity, atmospheric pressure, solar radiation, precipitation, and visibility at surface have been measured analyzed with statistical methods. At the site, the prevailing wind directions were SW in spring and summer, NNW in winter season. (author). 6 refs., 9 tabs., 4 figs.

  14. Risks assessment and forecasting long time rows of economic indicators

    Directory of Open Access Journals (Sweden)

    Gennadiy Pavlovich Bystray

    2012-09-01

    Full Text Available This paper reviews main approaches to risk assessment. The authors accented attention on the nonlinear approach to the theory of risks. It is proposed to define economic risk as the probability of threats that could have material adverse effect on the economic system under study and to change its current state. The method and the program product designed by the authors integrate a wide range of indicators of economic and financial activities at the regional level in the program-technical complex. This paper describes a new method for assessing synergistic and prediction of risk over long timerows ofeconomicindicators at theregional level, including methods of nonlinear and chaotic dynamics, enabling a pseudo-phase and phase portraits, to determine the volatility, to calculate fractal characteristics and predict the behavior of socio-economic indicators with modernized method of Hurst, to model based on recovery probability distribution function of nonequilibrium potential function, to determinethelocal and global stability of theregionaleconomy and to identify risks as the probability of the threats of an economic nature.

  15. Probabilistic Health Risk Assessment of Chemical Mixtures: Importance of Travel Times and Connectivity

    Science.gov (United States)

    Henri, Christopher V.; Fernàndez-Garcia, Daniel; de Barros, Felipe P. J.

    2014-05-01

    Subsurface contamination cases giving rise to groundwater pollutions are extensively found in all industrialized countries. Under this pressure, risk assessment methods play an important role in population protection by (1) quantifying the potential impact on human health of an aquifer contamination and (2) helping and driving decisions of groundwater-resource managers. Many reactive components such as chlorinated solvents or nitrates potentially experience attenuation processes under common geochemical conditions. This represents an attractive and extensively used remediation solution but leads often to the production of by-products before to reach a harmless chemical form. This renders mixtures of contaminants a common issue for groundwater resources managers. In this case, the threat posed by these contaminants to human health at a given sensitive location greatly depends on the competition between reactive and advective-dispersive characteristic times. However, hydraulic properties of the aquifer are known to be spatially variable, which can lead to the formation of preferential flow channels and fast contamination pathways. Therefore, the uncertainty on the spatial distribution of the aquifer properties controlling the plume travel time may then play a particular role in the human health risk assessment of chemical mixtures. We investigate here the risk related to a multispecies system in response to different degrees of heterogeneity of the hydraulic conductivity (K or Y =ln(K)). This work focuses on a Perchloroethylene (PCE) contamination problem followed by the sequential first-order production/biodegradation of its daughter species Trichloroethylene (TCE), Dichloroethylene (DCE) and Vinyl Chlorine (VC). For this specific case, VC is known to be a highly toxic contaminant. By performing numerical experiments, we evaluate transport through three-dimensional mildly (σY 2=1.0) and highly (σY 2=4.0) heterogeneous aquifers. Uncertainty on the hydraulic

  16. Oral bioaccessibility and human exposure assessment of cadmium and lead in market vegetables in the Pearl River Delta, South China.

    Science.gov (United States)

    Zhuang, Ping; Li, Yingwen; Zou, Bi; Su, Feng; Zhang, Chaosheng; Mo, Hui; Li, Zhian

    2016-12-01

    A systematic investigation into cadmium (Cd) and lead (Pb) concentrations and their oral bioaccessibility in market vegetables in the Pearl River Delta region were carried out to assess their potential health risks to local residents. The average concentrations of Cd and Pb in six species of fresh vegetables varied within 0.09-37.7 and 2.3-43.4 μg kg-1, respectively. Cadmium and Pb bioaccessibility were 35-66 % and 20-51 % in the raw vegetables, respectively, and found to be significantly higher than the cooked vegetables with 34-64 % for Cd and 11-48 % for Pb. The results indicated that Cd bioaccessibility was higher in the gastric phase and Pb bioaccessibility was higher in the small intestinal phase (except for fruit vegetables). Cooking slightly reduced the total concentrations and bioaccessibility of Cd and Pb in all vegetables. The bioaccessible estimated daily intakes of Cd and Pb from vegetables were far below the tolerable limits.

  17. 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.

  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. 7 CFR 1205.512 - Collecting handlers and time of collection of $1 per bale assessment.

    Science.gov (United States)

    2010-01-01

    ... bale assessment. 1205.512 Section 1205.512 Agriculture Regulations of the Department of Agriculture....512 Collecting handlers and time of collection of $1 per bale assessment. Collecting handlers and the time of collecting the $1 per bale assessment shall be as follows: (a) Except as provided in paragraph...

  20. 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.

  1. Threshold exceedance risk assessment in complex space-time systems

    Science.gov (United States)

    Angulo, José M.; Madrid, Ana E.; Romero, José L.

    2015-04-01

    Environmental and health impact risk assessment studies most often involve analysis and characterization of complex spatio-temporal dynamics. Recent developments in this context are addressed, among other objectives, to proper representation of structural heterogeneities, heavy-tailed processes, long-range dependence, intermittency, scaling behavior, etc. Extremal behaviour related to spatial threshold exceedances can be described in terms of geometrical characteristics and distribution patterns of excursion sets, which are the basis for construction of risk-related quantities, such as in the case of evolutionary study of 'hotspots' and long-term indicators of occurrence of extremal episodes. Derivation of flexible techniques, suitable for both the application under general conditions and the interpretation on singularities, is important for practice. Modern risk theory, a developing discipline motivated by the need to establish solid general mathematical-probabilistic foundations for rigorous definition and characterization of risk measures, has led to the introduction of a variety of classes and families, ranging from some conceptually inspired by specific fields of applications, to some intended to provide generality and flexibility to risk analysts under parametric specifications, etc. Quantile-based risk measures, such as Value-at-Risk (VaR), Average Value-at-Risk (AVaR), and generalization to spectral measures, are of particular interest for assessment under very general conditions. In this work, we study the application of quantile-based risk measures in the spatio-temporal context in relation to certain geometrical characteristics of spatial threshold exceedance sets. In particular, we establish a closed-form relationship between VaR, AVaR, and the expected value of threshold exceedance areas and excess volumes. Conditional simulation allows us, by means of empirical global and local spatial cumulative distributions, the derivation of various statistics of

  2. 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

  3. Screening for local and regional cancer recurrence in patients curatively treated for laryngeal cancer: definition of a high-risk group and estimation of the lead time.

    Science.gov (United States)

    Ritoe, Savitri C; Verbeek, André L M; Krabbe, Paul F M; Kaanders, Johannes H A M; van den Hoogen, Frank J A; Marres, Henri A M

    2007-05-01

    All patients treated for laryngeal cancer are offered the same follow-up schedule to detect asymptomatic locoregional recurrences. In this study, we evaluated the prognostic profile of patients for cancer recurrence and estimated the lead time. A cohort study was performed between 1990 and 1995. Cox proportional hazards model was used to analyze the prognostic factors. The effect of altering the follow-up for asymptomatic recurrence detection was determined after estimating the lead time. The variables cT classification, smoking, and histologic grade proved to be prognostic factors. The risk of locoregional failure was 15% in the low-risk group versus 29% in the high-risk group. The estimated lead time was 2 to 4 weeks. Risk profiles for locoregional relapse were defined. Intensifying the follow-up schedule is not advisable because the lead time is very short. An excessively high number of routine visits would have to be performed to increase the detection rate for asymptomatic recurrences. (c) 2006 Wiley Periodicals, Inc.

  4. 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

  5. Timing in a fluctuating environment: environmental variability and asymmetric fitness curves can lead to adaptively mismatched avian reproduction

    Science.gov (United States)

    Lof, Marjolein E.; Reed, Thomas E.; McNamara, John M.; Visser, Marcel E.

    2012-01-01

    Adaptation in dynamic environments depends on the grain, magnitude and predictability of ecological fluctuations experienced within and across generations. Phenotypic plasticity is a well-studied mechanism in this regard, yet the potentially complex effects of stochastic environmental variation on optimal mean trait values are often overlooked. Using an optimality model inspired by timing of reproduction in great tits, we show that temporal variation affects not only optimal reaction norm slope, but also elevation. With increased environmental variation and an asymmetric relationship between fitness and breeding date, optimal timing shifts away from the side of the fitness curve with the steepest decline. In a relatively constant environment, the timing of the birds is matched with the seasonal food peak, but they become adaptively mismatched in environments with temporal variation in temperature whenever the fitness curve is asymmetric. Various processes affecting the survival of offspring and parents influence this asymmetry, which collectively determine the ‘safest’ strategy, i.e. whether females should breed before, on, or after the food peak in a variable environment. As climate change might affect the (co)variance of environmental variables as well as their averages, risk aversion may influence how species should shift their seasonal timing in a warming world. PMID:22628472

  6. [Factors Influencing Lead Time in Multiple Sclerosis: Survey of Members of the German Multiple Sclerosis Society in Saxony-Anhalt].

    Science.gov (United States)

    Paulus, A; Hussack, S; Kugler, J

    2016-08-01

    Multiple sclerosis is a neurodegenerative disease of the central nervous system in which the myelin layer is disrupted. Early diagnosis and early therapy are decisive for the course of the disease. To analyze the time to diagnosis and the factors having an influence on this process, members of the German Multiple Sclerosis Society in Saxony-Anhalt (n = 941) were surveyed. Thanks to a return rate of 424 questionnaires (response rate ≈45 %), the results provide a good overview of MS patients in this region. Almost 80 % of the respondents were female. The median time to diagnosis was 6.35 years. On average, women were diagnosed 2.93 years later than men (p≤ 0.05; U test). The time to diagnosis has decreased over the last decades. Younger age at the time of the first symptoms seems to be a positive factor for early diagnosis. A recall bias cannot be outruled since all the data are based on individual experience. The results of the self-help group samples cannot be generalized. Further surveys are needed to analyze why it takes over six years to establish the diagnosis of multiple sclerosis. © Georg Thieme Verlag KG Stuttgart · New York.

  7. Beyond Screen Time: Assessing Recreational Sedentary Behavior among Adolescent Girls

    Directory of Open Access Journals (Sweden)

    Katherine W. Bauer

    2012-01-01

    Full Text Available Most studies of sedentary behavior have focused on television use or screen time. This study aims to examine adolescent girls' participation in a variety of recreational sedentary behaviors (e.g., talking on the phone and hanging around, and their association with physical activity (PA, dietary behaviors, and body mass index. Data were from a sample of 283 adolescent girls. Recreational sedentary behavior, PA, and dietary behaviors were self-reported, and girls' height and weight were measured. Over 95% of girls engaged in at least one recreational sedentary behavior during the recall period. Watching television and hanging around were the most common behaviors. Watching television, using the Internet, and hanging around were associated with less PA; watching television, hanging around, and talking on the phone were associated with less healthful dietary behaviors. No associations were found with body mass index. Interventions may benefit from capitalizing on and intervening upon girls' common recreational sedentary behaviors.

  8. 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...... diffuseness conditions are realized by altering the directions of arrival of the reflected waves. This model also considers room characteristics such as the volume, absorption of surfaces, air absorption and geometrical divergence. Listening tests are performed in an anechoic 64-loudspeaker based virtual...... acoustic environment to examine how sensitive the human auditory system is to changes in the diffuseness condition, which factors are most crucial and which conditions are most favourable in music halls. Two types of stimuli, a music signal and an impulse response, are tested under the same diffuseness...

  9. 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

  10. 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.

  11. Flipping the classroom: Case-based learning, accountability, assessment, and feedback leads to a favorable change in culture.

    Science.gov (United States)

    Mokadam, Nahush A; Dardas, Todd F; Hermsen, Joshua L; Pal, Jay D; Mulligan, Michael S; Jacobs, L Myria; Wood, Douglas E; Verrier, Edward D

    2017-04-01

    The 88-week Thoracic Surgery Curriculum is challenging to implement because of the large content in a traditional lecture format. This study investigates flipping the classroom by using a case-based format designed to stimulate resident preparation and engagement. The didactic conference format was altered. Curricular reading assignments, case review, and conference participation prepared residents for novel formative assessment quizzes. Ten residents participated, and faculty served as controls. Scores were compared with the use of linear regression adjusted for clustering of responses for each person. A survey was administered to determine impressions of this educational technique. A majority of residents completed curricular readings (82%) and reviewed case presentations (79%). Resident performance initially lagged behind faculty but exceeded faculty performance by the conclusion (interaction P = .047). Junior resident overall performance was superior to senior residents over the entire analysis (P = .026); however, both groups improved over time similarly (P = .34) Increased reading from the curriculum (5% increase per level, P = .001) and case presentation review (6% increase per level, P learning principles, flipping the classroom in this manner may improve educational culture by enhancing accountability, assessment, and feedback. Copyright © 2016 The American Association for Thoracic Surgery. Published by Elsevier Inc. All rights reserved.

  12. Climate change leads to differential shifts in the timing of annual cycle stages in a migratory bird.

    Science.gov (United States)

    Tomotani, Barbara M; van der Jeugd, Henk; Gienapp, Phillip; de la Hera, Iván; Pilzecker, Jos; Teichmann, Corry; Visser, Marcel E

    2018-02-01

    Shifts in reproductive phenology due to climate change have been well documented in many species but how, within the same species, other annual cycle stages (e.g. moult, migration) shift relative to the timing of breeding has rarely been studied. When stages shift at different rates, the interval between stages may change resulting in overlaps, and as each stage is energetically demanding, these overlaps may have negative fitness consequences. We used long-term data of a population of European pied flycatchers (Ficedula hypoleuca) to investigate phenological shifts in three annual cycle stages: spring migration (arrival dates), breeding (egg-laying and hatching dates) and the onset of postbreeding moult. We found different advancements in the timing of breeding compared with moult (moult advances faster) and no advancement in arrival dates. To understand these differential shifts, we explored which temperatures best explain the year-to-year variation in the timing of these stages, and show that they respond differently to temperature increases in the Netherlands, causing the intervals between arrival and breeding and between breeding and moult to decrease. Next, we tested the fitness consequences of these shortened intervals. We found no effect on clutch size, but the probability of a fledged chick to recruit increased with a shorter arrival-breeding interval (earlier breeding). Finally, mark-recapture analyses did not detect an effect of shortened intervals on adult survival. Our results suggest that the advancement of breeding allows more time for fledgling development, increasing their probability to recruit. This may incur costs to other parts of the annual cycle, but, despite the shorter intervals, there was no effect on adult survival. Our results show that to fully understand the consequences of climate change, it is necessary to look carefully at different annual cycle stages, especially for organisms with complex cycles, such as migratory birds. © 2017

  13. 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.

  14. Approaches of Seismic Vulnerability Assessments in Near Real Time Systems

    Science.gov (United States)

    Frolova, Nina; Larionov, Valery; Bonnin, Jean; Ugarov, Alexander

    2014-05-01

    Data on seismic vulnerability of existing building stock and other elements at risk are rather important for near real time earthquake loss estimations by global systems. These data together with information on regional peculiarities of seismic intensity attenuation and other factors contribute greatly to the reliability of strong event consequences estimated in emergency mode. There are different approaches for vulnerability functions' development and the empirical one is most often used. It is based on analysis of engineering consequences of past strong events when well documented descriptions of damage to different building types and other elements at risk are available for the earthquake prone area under consideration. In the case such data do not exist the information from macroseismic scales may be used. Any approach of vulnerability functions' development requires the proper classification of buildings and structures under consideration. According to national and international building codes, as well as macroseismic scales different buildings' classifications exist. As a result the global systems, such as Extremum and PAGER, as well as GEM project make use of the non-unified information on building stock distribution worldwide. The paper addresses the issues of buildings' classification and city models in terms of these classifications. Distribution of different buildings types in Extremum and PAGER/GEM systems is analyzed for earthquake prone countries. The comparison of city models revealed significant differences which influence greatly earthquake loss estimations in emergency mode. The paper describes the practice of city models' development which make use of space images and web technology in social networks. It is proposed to use the G8 country (and other) initiatives related to open data and transparency aimed at improving building stock distribution and global population databases.

  15. 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.

  16. 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.

  17. Performance evaluation of a merge supply system with a distribution centre, two reliable suppliers, one buffer and Erlang lead times

    Directory of Open Access Journals (Sweden)

    Vidalis, M.

    2012-01-01

    Full Text Available In this work a two echelon merge supply chain is examined. Specifically, two non identical reliable suppliers feed a distribution centre with a shared buffer. The first echelon consists of the distribution centre and the shared buffer, the second echelon includes two non identical reliable suppliers. There is an unlimited supply of materials to suppliers and an unlimited capacity shipping area after the distribution centre. In other words, suppliers are never starved, and the distribution centre is never blocked. The materials are processed by suppliers with rates following the Erlang distribution. The distribution centre has a reliable machine that pushes material with service times following the Erlang distribution. Blocking appears when one or more suppliers finish their process and try to feed the buffer that is full. The supply network is modelled as a continuous time Markov process with discrete states. The structures of the transition matrices of those systems are explored and a computational algorithm is developed. Our aim is to generate stationary distributions for different values of system's parameters so as the various measures of the system can be estimated. Finally, for the mathematical programming model and the rest of the calculations the Matlab software is used.

  18. [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.

  19. Lead Test

    Science.gov (United States)

    ... Links Patient Resources For Health Professionals Subscribe Search Lead Send Us Your Feedback Choose Topic At a ... Related Content View Sources Also Known As Blood Lead Test Blood Lead Level BLL Formal Name Lead, ...

  20. Comparative assessment of blood lead levels of automobile technicians in organised and roadside garages in Lagos, Nigeria.

    Science.gov (United States)

    Saliu, Abdulsalam; Adebayo, Onajole; Kofoworola, Odeyemi; Babatunde, Ogunowo; Ismail, Abdussalam

    2015-01-01

    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 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.

  1. Nonlinear Time Reversal Acoustic Method of Friction Stir Weld Assessment Project

    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...

  2. Assessment of exposure to lead in humans and turtles living in an industrial site in Coatzacoalcos Veracruz, Mexico.

    Science.gov (United States)

    Pelallo-Martínez, N A; Ilizaliturri-Hernández, C A; Espinosa-Reyes, G; Carrizales-Yáñez, L; González-Mille, D J

    2011-06-01

    The intake of lead from the environment may occur thru various receptors. In order to measure lead levels absorbed, samples were taken from Children who live in three localities surrounding an industrial complex in Coatzacoalcos, Veracruz. Samples were also taken from turtles. Samples were analyzed and results were compared against the general population. In children tested, over 75% of all values were determined to be above CDC's safety levels of (10 μg/dL). The geometric mean lead concentration was 11.4 μg/dL, which is clearly higher around the industrial complex than in the general population. In turtles, lead blood levels in the exposed population were 2-fold above (24.2 μg/dL) those of turtles in the reference population (10.1 μg/dL). Lead levels observed represent a risk for both human and fauna health.

  3. Lead and the Romans

    Science.gov (United States)

    Reddy, Aravind; Braun, Charles L.

    2010-01-01

    Lead poisoning has been a problem since early history and continues into modern times. An appealing characteristic of lead is that many lead salts are sweet. In the absence of cane and beet sugars, early Romans used "sugar of lead" (lead acetate) to sweeten desserts, fruits, and sour wine. People most at risk would have been those who…

  4. Out with the old, in with the new: Assessing change in screen time when measurement changes over time.

    Science.gov (United States)

    Gunnell, Katie E; Brunet, Jennifer; Bélanger, Mathieu

    2018-03-01

    We examined if screen time can be assessed over time when the measurement protocol has changed to reflect advances in technology. Beginning in 2011, 929 youth (9-12 years at time one) living in in New Brunswick (Canada) self-reported the amount of time spent watching television (cycles 1-13), using computers (cycles 1-13), and playing video games (cycles 3-13). Using longitudinal invariance to test a shifting indicators model of screen time, we found that the relationships between the latent variable reflecting overall screen time and the indicators used to assess screen time were invariant across cycles (weak invariance). We also found that 31 out of 37 indicator intercepts were invariant, meaning that most indicators were answered similarly (i.e., on the same metric) across cycles (partial strong invariance), and that 28 out of 37 indicator residuals were invariant indicating that similar sources of error were present over time (partial strict invariance). Overall, across all survey cycles, 76% of indicators were fully invariant. Whereas issues were noted when new examples of screen-based technology (e.g., iPads) were added, having established partial invariance, we suggest it is still possible to assess change in screen time despite having changing indicators over time. Although it is not possible to draw definitive conclusions concerning other self-report measures of screen time, our findings may assist other researchers considering modifying self-report measures in longitudinal studies to reflect technological advancements and increase the precision of their results.

  5. An assessment of the differential quadrature time integration scheme for nonlinear dynamic equations

    Science.gov (United States)

    Liu, Jian; Wang, Xinwei

    2008-07-01

    In 1996, Xie [An assessment of time integration schemes for non-linear dynamic equations, Journal of Sound and Vibration 192(1) (1996) 321-331] presented an assessment on seven existing and commonly used time integration schemes for nonlinear dynamic equations. In this work, the differential quadrature (DQ) time integration scheme proposed by Fung in 2001 is assessed following the same procedures as Xie's. It is shown that accurate numerical results can be obtained by the DQ method when using much larger time step over the commonly used time integration schemes. Based on the results reported herein, some conclusions are drawn.

  6. Congruence of Organizational Self-Score and Audit-Based Organizational Assessments of Workplace Health Capabilities: An Analysis of the HealthLead Workplace Accreditation.

    Science.gov (United States)

    Katz, Abigail S; Pronk, Nicolaas P; Chestnut, Kristan; Pfeiffer, George J; Childress, Jennifer

    2016-05-01

    The aim of this study was to provide descriptive characteristics of companies accredited as part of the HealthLead Workplace Accreditation and to assess congruence between data reported via online organizational self-assessment and third-party onsite audit. Synthesized organizational level data collected through the HealthLead accreditation process (N = 22). Online self-assessment and onsite third-party audit data were compared using paired t-tests. Statistical tests revealed significantly higher onsite audit scores than organizational self-assessment scores. Descriptive analyses demonstrated that Outcomes Reporting was the lowest scoring area among all companies. Companies also varied widely in levels of Leadership Support for wellness. Gaps observed between organizational self-assessment and onsite audit scores were relatively stable across the sample, indicating that observed differences may be process related. Organizations awarded accreditation show a wide variation in Leadership Support, and Outcomes Reporting appears to be low across the sample.

  7. Efficiency of liming in controlling the mobility of lead in shooting range soils as assessed by different experimental approaches.

    Science.gov (United States)

    Levonmäki, M; Hartikainen, H

    2007-12-15

    Shooting range soils contaminated by lead (Pb) are a great environmental risk. Reducing mobility and leaching of Pb by liming, for example, has produced contradictory results. This laboratory study compares the efficiency of two liming agents differing in their reactivity, CaCO(3) and blast furnace slag (BFS), in diminishing the mobility of Pb. In a batch test, contaminated humic soil samples were incubated in closed vessels without and with liming materials added in quantities to correspond additions of 5 t ha(-1). Water soluble Pb (Pb(w)), dissolved organic carbon (DOC), pH and substrate induced respiration (SIR) in soils were monitored for 21 days. In the experiment carried out with freely drained vessels, contaminated humic soil treated without and with liming agents was leached five times during the experimental period of 141 days. Leachates were analyzed for pH, DOC and Pb. At the end of the experiment, soil samples were analyzed for pH, DOC, Pb(w), and SIR. In both systems, CaCO(3) raised pH and DOC more than BFS. The liming agents did not significantly differ in their effect on Pb chemistry. Neither had any effect on SIR: however, liming agents markedly reduced the leaching of Pb in the open system, while in the closed system they increased rather than reduced the extractability of Pb. Incubation in a closed vessel proved not to be a suitable experimental system for Pb mobility estimation, since the ionic strength may be raised to abnormal levels, resulting from accumulated reaction products of liming agents.

  8. Monitoring of lead load and its effect on neonatal behavioral neurological assessment scores in Guiyu, an electronic waste recycling town in China.

    Science.gov (United States)

    Li, Yan; Xu, Xijin; Wu, Kusheng; Chen, Gangjian; Liu, Junxiao; Chen, Songjian; Gu, Chengwu; Zhang, Bao; Zheng, Liangkai; Zheng, Minghao; Huo, Xia

    2008-10-01

    Guiyu is the major electronic waste (e-waste) recycling town in China. The primary purpose of this study was to measure the lead levels in neonates and examine the correlation between lead levels and neurobehavioral development. One hundred full-term neonates from Guiyu and fifty-two neonates from neighboring towns (control group) in the late summer of 2006 were selected for study. The lead levels in the umbilical cord blood (CBPb) and lead levels in meconium (MPb) of neonates were determined with atomic absorption spectrophotometry. The neonatal behavioral neurological assessment (NBNA) was conducted on all neonates. A questionnaire related to the exposure to lead of pregnant women was used as a survey of the neonates' mothers. Compared with the control group, neonates in Guiyu had significantly higher levels of lead (P e-waste recycling. Neonates with high levels of lead load have lower NBNA scores (P e-waste recycling activities related to lead contamination. This study suggests that environmental lead contamination due to e-waste recycling have an impact on neurobehavioral development of neonates in Guiyu.

  9. 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…

  10. Development of a questionnaire to assess sedentary time in older persons -- a comparative study using accelerometry

    NARCIS (Netherlands)

    Visser, M.; Koster, A.

    2013-01-01

    Background: There is currently no validated questionnaire available to assess total sedentary time in older adults. Most studies only used TV viewing time as an indicator of sedentary time. The first aim of our study was to investigate the self-reported time spent by older persons on a set of

  11. A statewide assessment of lead screening histories of preschool children enrolled in a Medicaid managed care program.

    Science.gov (United States)

    Vivier, P M; Hogan, J W; Simon, P; Leddy, T; Dansereau, L M; Alario, A J

    2001-08-01

    Despite the prominence of lead poisoning as a public health problem, recent Government Accounting Office reports indicate that only one fifth of children who are covered by Medicaid have been screened for lead poisoning. The purpose of this study was to examine the lead screening histories of children who were enrolled in a statewide, Medicaid managed care plan to determine the relative impact of the type of primary care provider site and family sociodemographic characteristics on the likelihood of being screened. The study also examined the prevalence of and risk factors for lead poisoning of children who had been screened. A random sample of 2000 preschool-age children was chosen from those who were enrolled continuously in the statewide, expanded, Medicaid managed care program for a 1-year period and between the ages of 19 and 35 months at the end of that year. Sociodemographic characteristics and lists of primary care providers were obtained from administrative data sets. Medical record audits at primary care provider sites were performed to obtain the lead screening histories of the children, including test dates and results. Data on 1988 children were used for study analyses, and 80% of these children had at least 1 documented blood lead level. Children whose primary care provider was an office-based physician were less likely to be screened as compared with patients of health centers, hospital-based clinics, and staff model health maintenance organizations (68%, 86%, 89%, and 91% respectively). Variation in screening rates persisted in a multivariate analysis controlling for family sociodemographic characteristics and practice level variation. Of the 1587 children who had a documented blood lead test, 467 children (29%) had a blood lead level of >/=10 mg/dL on at least 1 test. Blood lead screening rates in Rhode Island's Medicaid managed care program are dramatically higher than national estimates for children who are enrolled in Medicaid. Potential

  12. Human health risk assessment of lead, manganese and copper from scrapped car paint dust from automobile workshops in Nigeria.

    Science.gov (United States)

    Nduka, John Kanayochukwu; Onyenezi Amuka, John Paul; Onwuka, Jude Chinedu; Udowelle, Nnaemeka Arinze; Orisakwe, Orish Ebere

    2016-10-01

    The economic downturn in Nigeria and Structural Adjustment Programme led to the flooding of Nigerian market with imported used automobiles. Most of these vehicles needed refurbishing and reworking. The present study is a human health risk assessment of metal exposure resulting from reworking of imported used vehicles in Nigeria. Scrap paint dusts from 56 Japanese made cars were collected from 8 different mechanic villages (workshops A-H] in Southeastern Nigeria. Scrap paints were homogenized, mixed, divided into fine particles and digested by standard method. The filtrates were assayed of lead, manganese and copper with atomic absorption spectrophotometry (AAS). Workshop B has the highest concentration of Pb (4.26 ± 0.93). Manganese in workshops A and F were (3.31 ± 0.85) and (3.04 ± 0.47) respectively and were higher than the levels from workshops C, B, D, G and H. Copper in workshop D (7.11 ± 0.21) was significantly greater than the other workshops. The highest hazard quotient (HQ) through ingestion, inhalation and dermal exposures in adults were 9.44E-05 (workshop B), 4.20E-01 (workshop B) and 1.08E-05 (workshop D) respectively. The highest values for HQ through ingestion, inhalation and dermal in children were 8.82E-04, 7.61E-01 and 2.86E-05 all in workshop B respectively. For children, the highest carcinogenic risk levels were 7.05E-08, 6.09E-05 and 2.29E-10 for ingestion, inhalation and dermal exposures respectively. In adults, the carcinogenic risk levels were 7.55E-09, 3.39E-05 and 8.67E-10 for ingestion, inhalation and dermal exposures respectively. Chronic exposure to scrap car paint dusts may be of significant public health importance in Nigeria as this may add to the body burden of some heavy metals.

  13. Economic Design of Multi-echelon Inventory System with Variable Lead Time and Service Level Constraint in a Fuzzy Cost Environment

    OpenAIRE

    S. Priyan; R. Uthayakumar

    2016-01-01

    Normally, human based industrial decision making involves both quantitative and qualitative input factors such as ordering cost, setup cost, etc. Thus the practitioners should be careful in accounting flexibility in the input factors. This paper optimizes an inventory system by employing mathematical model with variable lead time and service level constraint (SLC) in a fuzzy cost environment. Fuzziness is established by allowing the cost components imprecise and vague to certain extent. Trape...

  14. Students' Feedback Preferences: How Do Students React to Timely and Automatically Generated Assessment Feedback?

    Science.gov (United States)

    Bayerlein, Leopold

    2014-01-01

    This study assesses whether or not undergraduate and postgraduate accounting students at an Australian university differentiate between timely feedback and extremely timely feedback, and whether or not the replacement of manually written formal assessment feedback with automatically generated feedback influences students' perception of feedback…

  15. 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

    to reduce the number of measurements needed in the welfare assessment system WelFur-Mink in the different production periods without compromising the validity of the assessment. There seems to be an effect of date of the assessment in the nursing period, which can be handled elegantly if the other two...

  16. Jewellery: alloy composition and release of nickel, cobalt and lead assessed with the EU synthetic sweat method.

    Science.gov (United States)

    Hamann, Dathan; Thyssen, Jacob P; Hamann, Carsten R; Hamann, Curtis; Menné, Torkil; Johansen, Jeanne D; Spiewak, Radoslaw; Maibach, Howard; Lundgren, Lennart; Lidén, Carola

    2015-10-01

    Several studies have shown nickel and cobalt release from jewellery by using spot tests, but the metal composition of jewellery is largely unknown. To evaluate the metal composition of a large worldwide sample of mainly inexpensive jewellery items, and investigate the release of nickel, cobalt and lead from a subsample by using EN 1811:1998-required methods. A total of 956 metallic jewellery components were examined with X-ray fluorescence spectroscopy. A subsample of 96 jewellery items purchased in the United States were investigated for nickel, cobalt and lead release by the use of artificial sweat immersion and plasma optical emission spectroscopy. Eighteen elements were detected. The 10 most frequently occurring were, in order of frequency, copper, iron, zinc, nickel, silver, chromium, tin, manganese, lead, and cobalt. Release of nickel was noted from 79 of the 96 US samples (0.01-98 µg/cm(2) /week), release of cobalt from 35 samples (0.02-0.5 µg/cm(2) /week), and release of lead from 37 samples (0.03-2718 µg/cm(2) /week). We present here a comprehensive list of the most frequently encountered metals in jewellery and fashion accessories. Different allergenic and non-allergenic metals are utilized. We also report the frequent release of nickel, cobalt and lead from these objects, despite legislative restrictions. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  17. 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 ...

  18. Rail passengers’ time use and utility assessment: 2010 findings from Great Britain with multivariate analysis

    OpenAIRE

    Susilo , Yusak O.; Lyons, Glenn; Jain, Juliet; Atkins, Steve

    2013-01-01

    Using data from Great Britain’s National Passenger Survey 2010 this paper examines the travel time use of rail passengers and their indicative assessment of its utility. The paper explores the impacts of individuals’ socio demographic characteristics, types of activity undertaken and the perceived difficulties that may be faced by the travellers on their assessment of travel time use utility. The study shows that only 13% of travellers considered their travel time as wasted. However, this var...

  19. CYP3A time-dependent inhibition risk assessment validated with 400 reference drugs.

    Science.gov (United States)

    Zimmerlin, Alfred; Trunzer, Markus; Faller, Bernard

    2011-06-01

    Although reversible CYP3A inhibition testing is well established for predicting the drug-drug interaction potential of clinical candidates, time-dependent inhibition (TDI) has become the focus of drug designers only recently. Failure of several late-stage clinical candidates has been attributed to TDI, and this mechanism is also suspected to play a role in liver toxicities often observed in preclinical species. Measurement of enzyme inactivation rates (k(inact) and K(I)) is technically challenging, and a great deal of variability can be found in the literature. In this article, we have evaluated the TDI potential for 400 registered drugs using a high-throughput assay format based on determination of the inactivation rate (k(obs)) at a single concentration of test compound (10 μM). The advantages of this new assay format are highlighted by comparison with data generated using the IC₅₀ shift assay, a current standard approach for preliminary assessment of TDI. With use of an empirically defined positive/negative k(obs) bin of 0.02 min⁻¹, only 4% of registered drugs were found to be positive. This proportion increased to more than 20% when in-house lead optimization molecules were considered, emphasizing the importance of identifying this property in selection of promising drug candidates. Finally, it is suggested that the data and technology described here may be a good basis for building structure-activity relationships and in silico modeling.

  20. Assessment of Lead and cadmium contamination and influencing factors in raw milk from regions of Hamadan province

    Directory of Open Access Journals (Sweden)

    A Vahidinia

    2013-11-01

    Full Text Available Regarding the significance of harmful effects of heavy metals in human diet, this study aimed to investigate the concentrations of lead and cadmium in raw milk samples. To achieve this goal, a total number of 48 samples was collected from various regions of Hamadan province during April 2011. The samples were analyzed by atomic absorption spectroscopy. According to the results, the mean concentrations of lead and cadmium estimated at 4.48 and 3.21µg/kg, respectively which were below the approved level determined by WHO as well as FAO. Although, concentrations of Pb and Cd among the various sampling regions revealed a significant (p

  1. 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

  2. Haemodynamic vector personalization of a quadripolar left ventricular lead used for cardiac resynchronization therapy: use of surface electrocardiogram and interventricular time delays.

    Science.gov (United States)

    Trolese, Luca; Biermann, Juergen; Hartmann, Maximilian; Schluermann, Fabienne; Faber, Thomas S; Bode, Christoph; Asbach, Stefan

    2014-10-01

    The choice of left ventricular pacing configurations (LVPCs) of quadripolar leads used for cardiac resynchronization therapy (CRT) affects haemodynamic response and thus may be a tool for device optimization. The value of surface electrocardiograms and interventricular time delays (IVDs) for optimization is unknown. Sixteen patients implanted with a CRT device with a quadripolar LV lead underwent invasive testing of LV dP/dt. QRS durations at baseline (bl) and during biventricular pacing (biv) were measured using different LVPCs (total of 141 LVPCs; 8.8 per patient). Variations in QRS duration during biv were calculated for each patient (ΔQRS) and, when compared with intrinsic QRS duration, for all LVPCs (ΔQRSLVPC). Interventricular time delays between the poles of the LV lead were obtained from intracardiac electrograms. ΔIVD was calculated as IVDmax - IVDmin. Parameters were correlated with LV dP/dt. ΔQRS and ΔQRSLVPC both significantly correlated with LV dP/dt (P 168 ms (P personalization in the individual. Reductions in QRS width, but not IVDs, correlate with acute haemodynamic response. Intraindividually, in 75% of patients, the LVPC with the shortest QRS duration gives equal or superior haemodynamic results when compared with the LVPC with longest QRS duration. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2014. For permissions please email: journals.permissions@oup.com.

  3. 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

  4. 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...... that matrix reduction and time domain simulation are the most critical operations....

  5. Ignoring Individual Differences in Times of Assessment in Growth Curve Modeling

    Science.gov (United States)

    Coulombe, Patrick; Selig, James P.; Delaney, Harold D.

    2016-01-01

    Researchers often collect longitudinal data to model change over time in a phenomenon of interest. Inevitably, there will be some variation across individuals in specific time intervals between assessments. In this simulation study of growth curve modeling, we investigate how ignoring individual differences in time points when modeling change over…

  6. 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...

  7. 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.…

  8. 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 ...

  9. Characterization of organic gunshot residues in lead-free ammunition using a new sample collection device for liquid chromatography-quadrupole time-of-flight mass spectrometry.

    Science.gov (United States)

    Benito, Sandra; Abrego, Zuriñe; Sánchez, Alicia; Unceta, Nora; Goicolea, M Aranzazu; Barrio, Ramón J

    2015-01-01

    The identification of characteristic organic gunshot residues (OGSR) provides conclusive evidence in the elucidation of elemental profiles when lead-free ammunition is fired. OGSR also prevents false negatives. Toward this aim, a quick and efficient method based on liquid chromatography-quadrupole time-of-flight mass spectrometry (LC-QTOF) was developed to detect and identify 18 gunpowder additives in gunshot residues (GSR). The unequivocal identification of target analytes was assured by using MS/MS mode. Swabs were compared with home-modified tape lift supports covered with a PTFE layer to determine the better sampling technique. The modified tape lift provided better extraction recoveries and enabled the analysis of inorganic and organic GSR simultaneously. The developed method was applied to the analysis of GSR from four different lead-free ammunitions. Diphenylamine and its nitrated degradation products and centralites were identified in all samples, providing strong evidence of GSR. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  10. Proposta de aplicação da abordagem Quick Response Manufacturing (QRM para a redução do lead time em operações de escritório Proposal for implementation of the approach Quick Response Manufacturing (QRM to reduce lead-time in office operations

    Directory of Open Access Journals (Sweden)

    Andrey Domingues de Lima

    2013-03-01

    Full Text Available A administração eficiente e eficaz do lead time pode criar vantagens competitivas para as empresas. Uma abordagem que possui a preocupação de reduzir o lead time é a Manufatura de Resposta Rápida (QRM - Quick Response Manufacturing. O objetivo do presente trabalho é propor a aplicação de princípios e técnicas do QRM para redução do lead time do processo de orçamentação de uma empresa fabricante de materiais de escrita situada no Brasil. Para tanto, utilizou-se a pesquisa teórico-conceitual e o estudo de caso como procedimentos de pesquisa. Verificou-se que a empresa estudada poderá obter vantagens significativas com a adoção desta abordagem. Os resultados esperados por meio da implantação da proposta mostram uma redução de 38,1% no lead time total do processo de orçamentação da empresa estudada. Esse artigo contribui para maior divulgação e compreensão da abordagem QRM e de seus benefícios.The efficient and effective management of lead-time can create competitive advantages for companies. One approach that has the preoccupation to reduce lead-time is the Quick Response Manufacturing. The aim of this paper is to propose the implementation of principles and techniques of QRM for lead-time reduction in the budgeting process of an enterprise of writing materials (general writing located in Brazil. To this end, the theoretical-conceptual research and case study were used as research procedures. It was found that the studied company could obtain significant benefits by adopting this approach. The expected results through the implementation of the proposal show a decrease of 38.1% in the total lead-time of the budgeting process of the company studied. This paper contributes to a greater dissemination and understanding of the QRM approach and its benefits.

  11. 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.

  12. Heat wave over India during summer 2015: an assessment of real time extended range forecast

    Science.gov (United States)

    Pattanaik, D. R.; Mohapatra, M.; Srivastava, A. K.; Kumar, Arun

    2017-08-01

    Hot winds are the marked feature of summer season in India during late spring preceding the climatological onset of the monsoon season in June. Some years the conditions becomes very vulnerable with the maximum temperature ( T max) exceeding 45 °C for many days over parts of north-western, eastern coastal states of India and Indo-Gangetic plain. During summer of 2015 (late May to early June) eastern coastal states, central and northwestern parts of India experienced severe heat wave conditions leading to loss of thousands of human life in extreme high temperature conditions. It is not only the loss of human life but also the animals and birds were very vulnerable to this extreme heat wave conditions. In this study, an attempt is made to assess the performance of real time extended range forecast (forecast up to 3 weeks) of this scorching T max based on the NCEP's Climate Forecast System (CFS) latest version coupled model (CFSv2). The heat wave condition was very severe during the week from 22 to 28 May with subsequent week from 29 May to 4 June also witnessed high T max over many parts of central India including eastern coastal states of India. The 8 ensemble members of operational CFSv2 model are used once in a week to prepare the weekly bias corrected deterministic (ensemble mean) T max forecast for 3 weeks valid from Friday to Thursday coinciding with the heat wave periods of 2015. Using the 8 ensemble members separately and the CFSv2 corresponding hindcast climatology the probability of above and below normal T max is also prepared for the same 3 weeks. The real time deterministic and probabilistic forecasts did indicate impending heat wave over many parts of India during late May and early June of 2015 associated with strong northwesterly wind over main land mass of India, delaying the sea breeze, leading to heat waves over eastern coastal regions of India. Thus, the capability of coupled model in providing early warning of such killer heat wave can be very

  13. Real-Time Safety Risk Assessment Based on a Real-Time Location System for Hydropower Construction Sites

    Directory of Open Access Journals (Sweden)

    Hanchen Jiang

    2014-01-01

    Full Text Available 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.

  14. Leading by the hand: Exploring the factors affecting individual student engagement with self-directed mobile assessment

    Directory of Open Access Journals (Sweden)

    Ceridwen Coulby

    2011-06-01

    Full Text Available This paper examines the role of the individual student and his/her engagement with self-directed mobile assessment. The findings presented in this paper are based on the results of the ALPS (Assessment and Learning in Practice Settings CETL (Centre for Excellence in Teaching and Learning programme, a 5 year examination of the use of mobile technology for interprofessional, formative, work-based assessment among health and social care students. Analysing the results of multiple focus groups across a number of health and social care professions we found that learner engagement with self-directed mobile assessment is dependent on internal and external factors. In this paper we explore the internal factors, namely that of learner goal, confidence and stage of self-direction (Grow, 1991.

  15. 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.

  16. DECELERATION OF ELECTRON VE LOCITY BASED ON THE WAVE- PARTICLE DUALITY LEADS TO RE LATIVE TIME ACCELERATION: HYPOTHESIS OF INCREASED BIOPHYSICAL REACTION VELOCITY

    Directory of Open Access Journals (Sweden)

    Horst Koch

    2013-03-01

    Full Text Available The high speed of biological processes such as photosynthesis, enzymatic reactions or neuronal activity cannot completely be explained on the basis of classic physical approaches. Different quantum biology effects such as tunnelling have been postulated. We hypothetically admit that deceleration of electron velocity based on light-particle duality of electrons leads to time acceleration. Deceleration from the status of light towards a status of a particle may therefore speed up biochemical or biophysical reactions in the atomic or molecular dimension. Electrophysiological and biological phenomena are discussed on the basis of the hypothesis

  17. “Hartnell's time machine” reprise: Further implications of zinc, lead and copper in the thumbnail of a Franklin expedition crewmember

    OpenAIRE

    Millar, Keith; Bowman, Adrian W.

    2017-01-01

    Christensen et al. (2016) have described the application of synchrotron micro-X-ray fluorescence mapping, stable isotopic analysis and laser-ablation inductively-coupled plasma mass spectrometry to provide a unique and dynamic time scale of the concentration of metals in the thumbnail of John Hartnell who was a member of the 1845 British Royal Naval “Franklin expedition” which met a fatal end in the Arctic. Their finding of low levels of lead and zinc in Hartnell's thumbnail has questioned th...

  18. 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

  19. Assessment of Clogging Dynamics in Permeable Pavement Systems with Time Domain Reflectometers

    Science.gov (United States)

    Infiltration is a primary functional mechanism in green infrastructure stormwater controls. This study used time domain reflectometers (TDRs) to measure spatial infiltration and assess clogging dynamics of permeable pavement systems in Edison, NJ, and Louisville, KY. In 2009, t...

  20. Model-Based Real Time Assessment of Capability Left for Spacecraft Under Failure Mode Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The proposed project is aimed at developing a model based diagnostics system for spacecraft that will allow real time assessment of its state, while it is impacted...

  1. Using Online Assessment to Replace Invigilated Assessment in Times of Natural Disaster: Are Some Online Assessment Conditions Better than Others?

    Science.gov (United States)

    Agnew, Steve; Hickson, Stephen

    2012-01-01

    As a result of the Canterbury earthquake on 4 September 2010, and associated aftershocks on 22 February 2011 and 13 June 2011, final examinations in the two first-year Economics papers at Canterbury University were cancelled at short notice in Semester 1, 2011. The final examination weightings were spread over the remaining assessments to obtain a…

  2. Uptake, prevalence and predictors of first-time use for the 75+ Health Assessment Scheme.

    Science.gov (United States)

    Dolja-Gore, Xenia; Tavener, Meredith; Majeed, Tazeen; Nair, Balakrishnan R; Byles, Julie E

    2017-10-01

    In 1999, the Australian Federal Government introduced Medicare items for Health Assessments for people aged 75 years and older (75+ health assessments). This research examined uptake of these assessments and identified predictors of use by women from the Australian Longitudinal Study on Women's Health (ALSWH). Assessments were identified for each year from 1999 to 2013 using linked Medicare data. Time to first assessment was examined, as well as social and health factors associated with having an assessment. From 1999 to 2013, 61.8% of women had at least one assessment. Almost one-third had an assessment within 2 years of their introduction, 25% of women died before having an assessment and 13% survived but did not have an assessment. Factors associated with assessment included being widowed, private health insurance, marital status, education, having arthritis and urinary incontinence, and less difficulty managing on income. Many women never received an assessment, and many only received one. Promotion of the 75+ health assessments is necessary among older women to increase uptake.

  3. 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...

  4. 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, ...... with the sensitivity-based voltage stability assessment method is explored....

  5. Assessment of susceptibility to pollution in littoral waters using the concept of recovery time.

    Science.gov (United States)

    Gómez, Aina G; Juanes, José A; Ondiviela, Bárbara; Revilla, José A

    2014-04-15

    Susceptibility to pollution can be related to the flushing capacity of aquatic systems. Transport time scales constitute a useful tool for representing the water exchange and transport processes. A new transport time scale, recovery time, and a methodology to estimate it by means of numerical models is hereby developed. Recovery time, calculated in Gijon, Santander and Tarragona harbours, is significantly related to physical, chemical and biological water quality indicators. Susceptibility, assessed through recovery time values, provides spatial patterns of expected flushing capacity, being sensitive to physical and hydrodynamic characteristics. The developed method is appropriate to estimate recovery time and assess susceptibility against pollution in littoral waters having great potential to be applied to different disciplines. Recovery time could be used in littoral waters as a surrogate of water quality indicators, to establish efficient monitoring programs, to define and characterize modified water bodies or to improve the design of marine infrastructures. Copyright © 2014 Elsevier Ltd. All rights reserved.

  6. Growth rates and interface shapes in germanium and lead tin telluride observed in-situ, real-time in vertical Bridgman furnaces

    Science.gov (United States)

    Barber, P. G.; Berry, R. F.; Debnam, W. J.; Fripp, A. L.; Woodell, G.; Simchick, R. T.

    1995-01-01

    Using the advanced technology developed to visualize the melt-solid interface in low Prandtl number materials, crystal growth rates and interface shapes have been measured in germanium and lead tin telluride semiconductors grown in vertical Bridgman furnaces. The experimental importance of using in-situ, real time observations to determine interface shapes, to measure crystal growth rates, and to improve furnace and ampoule designs is demonstrated. The interface shapes observed in-situ, in real-time were verified by quenching and mechanically induced interface demarcation, and they were also confirmed using machined models to ascertain the absence of geometric distortions. Interface shapes depended upon the interface position in the furnace insulation zone, varied with the nature of the crystal being grown, and were dependent on the extent of transition zones at the ends of the ampoule. Actual growth rates varied significantly from the constant translation rate in response to the thermophysical properties of the crystal and its melt and the thermal conditions existing in the furnace at the interface. In the elemental semiconductor germanium the observed rates of crystal growth exceeded the imposed translation rate, but in the compound semiconductor lead tin telluride the observed rates of growth were less than the translation rate. Finally, the extent of ampoule thermal loading influenced the interface positions, the shapes, and the growth rates.

  7. 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.

  8. External costs of atmospheric lead emissions from a waste-to-energy plant: a follow-up assessment of indirect neurotoxic impacts via topsoil ingestion

    DEFF Research Database (Denmark)

    Pizzol, Massimo; Møller, Flemming; Thomsen, Marianne

    2013-01-01

    magnitude as direct costs previously investigated, both in the case of actual emission rates and in the case of future emission scenarios for lead. Among the various modelling parameters, the choices of time horizon and of social discount rate have the most influential effect: discounting of future impacts...

  9. FaceTime validation study: Low-cost streaming video for cytology adequacy assessment.

    Science.gov (United States)

    Agarwal, Shweta; Zhao, Lichao; Zhang, Roy; Hassell, Lewis

    2016-03-01

    Adequacy assessment for fine-needle aspiration procedures is a standard of care in large medical centers. Although the benefits of this approach include higher adequacy rates with fewer passes, it costs cytopathologist time and affects other clinical responsibilities. The objective of the current study was to evaluate the use of mobile video streaming (FaceTime) technology with the help of smartphone adapters attached to microscopes for remote adequacy assessment of cytologic samples. The study consisted of 2 phases: Phase 1 was a retrospective assessment of 25 samples by a primary pathologist with simultaneous streaming to a second pathologist using a smartphone (iPhone/iPad) FaceTime connection. Data on the adequacy of each sample and preliminary diagnoses were recorded. In phase 2, live cases were assessed prospectively by an onsite primary pathologist and by a remote pathologist using an iPhone/iPad-FaceTime connection. The testing phase involved prospective assessment of additional samples with a resident or cytotechnologist as the slide driver. In phase 1, retrospective evaluation of 25 samples yielded considerable agreement (22 of 25 samples; 88%) between onsite and remote adequacy assessments. Three samples (12%) yielded results that did not agree, including 2 samples that were read as adequate in the onsite evaluation that were assessed as indeterminate using FaceTime. In phase 2 and in the testing phase, 14 samples exhibited considerable agreement on both adequacy and preliminary diagnosis (6 samples in phase 2 and 8 samples in the testing phase) and are currently available for reporting. Problems encountered include software version standardization, camera alignment, and (rarely) comprehension of the audio stream. The current data indicate that iPhone/iPad FaceTime technology can be used to perform remote adequacy assessments of fine-needle aspirations and can help save valuable time for pathologists. © 2015 American Cancer Society.

  10. Lead speciation in indoor dust: a case study to assess old paint contribution in a Canadian urban house.

    Science.gov (United States)

    Beauchemin, Suzanne; MacLean, Lachlan C W; Rasmussen, Pat E

    2011-08-01

    Residents in older homes may experience increased lead (Pb) exposures due to release of lead from interior paints manufactured in past decades, especially pre-1960s. The objective of the study was to determine the speciation of Pb in settled dust from an urban home built during WWII. X-ray absorption near-edge structure (XANES) and micro-X-ray diffraction (XRD) analyses were performed on samples of paint (380-2,920 mg Pb kg(-1)) and dust (200-1,000 mg Pb kg(-1)) collected prior to renovation. All dust samples exhibited a Pb XANES signature similar to that of Pb found in paint. Bulk XANES and micro-XRD identified Pb species commonly found as white paint pigments (Pb oxide, Pb sulfate, and Pb carbonate) as well as rutile, a titanium-based pigment, in the paints still contribute to Pb in the settled dust for this 65-year-old home. The Pb speciation also provided a clearer understanding of the Pb bioaccessibility: Pb carbonate > Pb oxide > Pb sulfate. This study underscores the importance of taking precautions to minimize exposures to Pb in house dust, especially in homes where old paint is exposed due to renovations or deterioration of painted surfaces.

  11. Assessing the Availability of Healthier Children's Meals at Leading Quick-Service and Full-Service Restaurants.

    Science.gov (United States)

    Sliwa, Sarah; Anzman-Frasca, Stephanie; Lynskey, Vanessa; Washburn, Kyle; Economos, Christina

    2016-04-01

    To compare the calorie, fat, saturated fat, and sodium content of available children's meal combinations in leading restaurants with national recommendations. Cross-sectional. Children's menu offerings and corresponding nutrition information were collected (May, 2014) from Web sites of the top 10 quick-service (QSR) and top 10 full-service (FSR) restaurant chains that offered a children's menu and provided nutrition information. Total calories (kcal), percent calories from fat and saturated fat, and total sodium (mg) were calculated for children's meal combinations (QSR N = 1,363; FSR N = 6,654). Combinations with ≤ 600 kcal, ≤ 35% kcal from fat, ≤ 10% kcal from saturated fat, ≤ 770 mg sodium, and those that met all 4 of these criteria were identified. Frequencies by restaurant segment. The majority of QSR (72%) and FSR (63%) meal combinations had ≤ 600 kcal. Only 31.9% of combinations at QSRs and 21.7% at FSRs met all 4 criteria. In both segments the calorie target was most frequently met, and the sodium target the least. Children's meal combinations with ≤ 600 kcal are available at leading restaurant chains, but many meals fail to meet current national recommendations for fat, saturated fat, and sodium. Menu labeling legislation may address caloric content but implications for other nutrients remain unclear. Copyright © 2016 Society for Nutrition Education and Behavior. Published by Elsevier Inc. All rights reserved.

  12. Field and laboratory assessment of a coal processing effluent in the Leading Creek Watershed, Meigs County, Ohio

    Energy Technology Data Exchange (ETDEWEB)

    Kennedy, A.J.; Cherry, D.S.; Currie, R.J. [Virginia Polytechnique Institute & State University, Blacksburg, VA (USA). Dept. of Biology

    2003-04-01

    The U.S. Environmental Protection Agency has not recommended water quality criteria (WQC) to protect aquatic life from elevated sodium and sulfate concentrations, such as those associated with the coal-processing effluent of Meigs County Mine No. 31. This discharge, received by a tributary of the Leading Creek Watershed (SE Ohio), had a mean specific conductivity (SC) of 8,109 (7,750-8,750) {mu}S/cm and total metal concentrations below acute WQC. The mean 48h LC50 for Ceriodaphnia dubia in the effluent was 6,713 +/- 99 {mu}S/cm; mean 48h survival was 44% for study sites downstream of the effluent. The best indicators of impairment used in this study were Ceriodaphnia fecundity, in situ Corbicula fluminea growth, EPT minus Hydropsychidae (richness and relative abundance), and relative Ephemeroptera abundance. Mayflies, reduced by more than 99% below the effluent, were absent from all but the furthest downstream study site. SC was strongly correlated with Corbicula growth and EPT minus Hydropsychidae richness, suggesting the effluent was primarily responsible for biotic impairment. The results indicated that SC levels, a measure of dissolved solids, in the Leading Creek Watershed that exceeded about to 3,700 {mu}S/cm impaired sensitive aquatic fauna.

  13. Lead poisoning

    Science.gov (United States)

    ... or dust from lead-based paint. Toys and furniture painted before 1976. Painted toys and decorations made ... by decades of car exhaust or years of house paint scrapings. Lead is more common in soil ...

  14. Lead Poisoning

    Science.gov (United States)

    ... a hard, durable surface. In 1977, federal regulations banned lead from paint for general use. But homes ... OTHERS: Lead has recently been found in some plastic mini-blinds and vertical blinds which were made ...

  15. The Test Authors Speak: Reporting on an Author Survey of the Leading Tests Used in Gifted Assessment

    Science.gov (United States)

    Valler, Emilee C.; Burko, Jordan A.; Pfeiffer, Steven I.; Branagan, Alexandra M.

    2017-01-01

    The conceptualization of giftedness continues to be a widely debated topic within the field. Recently, there has been a shift from a psychometric view of giftedness to inclusion of conative and contextual factors. How one defines and conceptualizes "gifted" drives assessment and identification practices. Conceptualization also guides the…

  16. 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....

  17. Cumulative versus end-of-course assessment: effects on self-study time and test performance.

    Science.gov (United States)

    Kerdijk, Wouter; Cohen-Schotanus, Janke; Mulder, B Florentine; Muntinghe, Friso L H; Tio, René A

    2015-07-01

    Students tend to postpone preparation for a test until the test is imminent, which raises various risks associated with 'cramming' behaviours, including that for suboptimal learning. Cumulative assessment utilises spaced testing to stimulate students to study more frequently and to prevent procrastination. This randomised controlled study investigated how cumulative assessment affects time spent on self-study and test performance compared with end-of-course assessment. A total of 78 undergraduate medical students in a Year 2 pre-clinical course were randomly assigned to either of two conditions. Students in the cumulative assessment condition were assessed in weeks 4, 8 and 10. Students in the end-of-course assessment condition were assessed in week 10 only. Each week, students reported the number of hours they spent on self-study. Students in the cumulative assessment condition (n = 25) spent significantly more time on self-study than students in the end-of-course assessment condition (n = 37) in all weeks of the course except weeks 5, 9 and 10. Overall, the cumulative assessment group spent 69 hours more on self-study during the course than did the control group, although the control group spent 7 hours more in studying during the final week of the course than did the cumulative assessment group. Students in the cumulative assessment condition scored slightly higher on questions concerning the content of the last part of the course. Cumulative assessment encourages students to distribute their learning activities over a course, which leaves them more opportunity to study the content of the last part of the course prior to the final examination. There was no evidence for a short-term effect of cumulative assessment on overall knowledge gain. We hypothesise that larger positive effects might be found if retention were to be measured in the long term. © 2015 John Wiley & Sons Ltd.

  18. Assessment of reverberation time by two measurement systems for room electromagnetics analysis

    DEFF Research Database (Denmark)

    Bamba, Aliou; Joseph, Wout; Plets, David

    2011-01-01

    to measurement systems and antennas characteristics are discussed. The goal of this paper is the assessment of the reverberation time in an environment with different measurement systems. From the reverberation time one can derive the absorption area and hence the absorption cross section for humans in realistic...

  19. 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…

  20. 76 FR 17626 - National Climate Assessment Development and Advisory Committee; Announcement of Time Change and...

    Science.gov (United States)

    2011-03-30

    ... announces a change in the start time and provides the location of the meeting of the National Climate... National Oceanic and Atmospheric Administration National Climate Assessment Development and Advisory Committee; Announcement of Time Change and Meeting Location AGENCY: National Oceanic and Atmospheric...

  1. Real-Time Structural Damage Assessment Using Artificial Neural Networks and Antiresonant Frequencies

    Directory of Open Access Journals (Sweden)

    V. Meruane

    2014-01-01

    Full Text Available The main problem in damage assessment is the determination of how to ascertain the presence, location, and severity of structural damage given the structure's dynamic characteristics. The most successful applications of vibration-based damage assessment are model updating methods based on global optimization algorithms. However, these algorithms run quite slowly, and the damage assessment process is achieved via a costly and time-consuming inverse process, which presents an obstacle for real-time health monitoring applications. Artificial neural networks (ANN have recently been introduced as an alternative to model updating methods. Once a neural network has been properly trained, it can potentially detect, locate, and quantify structural damage in a short period of time and can therefore be applied for real-time damage assessment. The primary contribution of this research is the development of a real-time damage assessment algorithm using ANN and antiresonant frequencies. Antiresonant frequencies can be identified more easily and more accurately than mode shapes, and they provide the same information. This research addresses the setup of the neural network parameters and provides guidelines for the selection of these parameters in similar damage assessment problems. Two experimental cases validate this approach: an 8-DOF mass-spring system and a beam with multiple damage scenarios.

  2. Time-Tagged Risk/Reliability Assessment Program for Development and Operation of Space System

    Science.gov (United States)

    Kubota, Yuki; Takegahara, Haruki; Aoyagi, Junichiro

    We have investigated a new method of risk/reliability assessment for development and operation of space system. It is difficult to evaluate risk of spacecraft, because of long time operation, maintenance free and difficulty of test under the ground condition. Conventional methods are FMECA, FTA, ETA and miscellaneous. These are not enough to assess chronological anomaly and there is a problem to share information during R&D. A new method of risk and reliability assessment, T-TRAP (Time-tagged Risk/Reliability Assessment Program) is proposed as a management tool for the development and operation of space system. T-TRAP consisting of time-resolved Fault Tree and Criticality Analyses, upon occurrence of anomaly in the system, facilitates the responsible personnel to quickly identify the failure cause and decide corrective actions. This paper describes T-TRAP method and its availability.

  3. 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.

  4. Assessment of lead (Pb residues in organs and muscles of slaughtered pigs at Nsukka and Environs in Enugu state, Nigeria

    Directory of Open Access Journals (Sweden)

    Obioha Chidiebere Felix

    2016-12-01

    Full Text Available Objective: Heavy metals are serious environmental pollutants and their uptake and accumulation in the ecosystem, beyond safe limits, would cause direct consequences to food chain and ultimately to man. The present study was undertaken to ascertain the presence and levels of lead (Pb in muscles and organs of slaughtered pigs at Nsukka agricultural zone, Nigeria. Materials and methods: From a total of 160 slaughtered pigs, liver, kidney and muscle of each pig were collected and processed for the detection of lead residue using Atomic Absorption Spectrophotometer. Results: A prevalence rate of 81.25% was recorded for Pb residue in Nsukka agricultural zone. There is a strong association (P<0.0001 between occurrence of Pb residue and the source of samples. Mean concentrations of 0.0758 mg/kg, 0.1050 mg/kg and 0.0985 mg/kg were recorded in kidney, mean concentrations of 0.1676 mg/kg, 0.1235 mg/kg and 0.1955 mg/kg were recorded in liver and mean concentrations of 0.0598 mg/kg, 0.0870 mg/kg and 0.1020 mg/kg in muscle samples in Nsukka, orba and Obollo slaughter houses respectively. There is no significant (P<0.05 difference between the mean concentrations of the Pb in the liver, kidney and muscle samples (Nsukka, Orba and Obollo and its maximum permissible levels (MPL. Conclusion: More than half of the samples were positive for Pb and few samples that exceeded the MPL may pose human health threat to pork consumers in the study area. [J Adv Vet Anim Res 2016; 3(4.000: 392-398

  5. 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.

  6. Nursing time to program and assess deep brain stimulators in movement disorder patients.

    Science.gov (United States)

    Hunka, Karen; Suchowersky, Oksana; Wood, Susan; Derwent, Lorelei; Kiss, Zelma H T

    2005-08-01

    The use of deep brain stimulation (DBS) to treat movement disorders such as Parkinson's disease, essential tremor, and dystonia is increasing. Although some published literature describes the methods for DBS programming, the time and nursing requirements to run a DBS surgical program have not been examined previously. For this study, we prospectively recorded the time required for both assessments and programming of the DBS from the preoperative period to 1 year after surgery in a variety of patients. Results showed that the mean total time spent programming the stimulator and assessing these patients ranged from 18.0-36.2 hours per patient. It took twice as long to program the stimulator in patients with Parkinson's disease as it did in patients with essential tremor or dystonia. When setting up a program for movement disorders surgery, nursing time spent on patient assessment and programming should be considered in the workload.

  7. Assessing the performance of four leading-edge pXRF devices for trace metal measurement on contaminated soils in industrial and mining context (Wallonia, South Belgium).

    Science.gov (United States)

    Vandeuren, Aubry; Pereira, Benoît; Sonnet, Philippe

    2017-04-01

    In many countries, large areas where mining and smelting activities took place in the past now exhibit elevated soil metal concentration levels. In Belgium, as in many European countries, soil assays are performed by aqua regia digestion and ICP measurement which is a cost- and time-expensive protocol. The aim of this study is to assess if this protocol could be approximated or replaced by portable XRF measurement as this method is fast, low cost and can be used in situ. This study first focused on the evaluation of the performance of four leading-edge pXRF devices for measuring metal concentrations in a collection of Belgian soil samples from industrial and mining context and non-contaminated areas. Four soil preparation protocols were then tested with one device, involving (1) measurement on fresh soil, (2) in situ sample drying and sieving, (3) in laboratory sample drying and sieving and (4) in laboratory sample drying, sieving and crushing. The comparison of the pXRF devices showed that the performance of each device varies depending on the element measured. The precision of the XRF measurement and correlation with aqua regia measurement protocol both increased for most of the elements when drying and sieving soil samples. However, for Cu and Pb, the four devices provide good measurement results whatever the sample preparation protocol. Finally, we proved the suitability of pXRF devices on a real-world case study by delineating the extent of Pb soil contamination by in situ pXRF measurement on fresh soil.

  8. Determining lead sources in Mexico using the lead isotope ratio

    Directory of Open Access Journals (Sweden)

    Chaudhary-Webb Madhu

    2003-01-01

    Full Text Available OBJECTIVE: Lead poisoning can, in some cases, be traced to a specific route or source of exposure on the basis of the individual's blood lead isotope ratio. To assess the major source of lead exposure among women residing in Mexico City, we compared blood, ceramic, and gasoline lead isotope ratios. MATERIAL AND METHODS: The study population, randomly selected from participants of a large trial, (1/1996-12/1996 comprised of 16 women whose lead levels exceeded 10 µg/dl and who reported using lead-glazed ceramics. Lead isotope ratios were performed on a Perkin Elmer 5000 Inductively Coupled Plasma Mass Spectrometer (ICP-MS interfaced with a Perkin Elmer HGA-600MS Electrothermal Vaporization System (ETV. RESULTS: The isotope ratios (206Pb/204Pb, 207Pb/204Pb, and 208Pb/204Pb of both the blood specimens and their corresponding ceramic specimens were highly correlated, with r=0.9979, r²=0.9958, r=0.9957, r²=0.9915 and r=0.9945, r²=0.9890 values for the three isotope ratios, respectively, suggesting that the lead exposure most likely resulted from the use of these ceramic. Measurements of lead isotope ratios from leaded gasoline in use at the time of blood sampling, differed from those in blood and ceramics. CONCLUSIONS: Determining lead isotope ratios can be an efficient tool to identify a major source of lead exposure and to support the implementation of public health prevention and control measures.

  9. Assessing the Mobility of Lead, Copper and Cadmium in a Calcareous Soil of Port-au-Prince, Haiti

    Directory of Open Access Journals (Sweden)

    Urbain Fifi

    2013-11-01

    Full Text Available The presence of heavy metals in the environment constitutes a potential source of both soil and groundwater pollution. This study has focused on the reactivity of lead (Pb, copper (Cu and Cadmium (Cd during their transfer in a calcareous soil of Port-au-Prince (Haiti. Kinetic, monometal and competitive batch tests were carried out at pH 6.0. Two simplified models including pseudo-first-order and pseudo-second-order were used to fit the experimental data from kinetics adsorption batch tests. A good fit of these data was found with pseudo-second-order kinetic model which indicates the applicability of this model to describe the adsorption rates of these metals on the soil. Monometal batch tests indicated that both Langmuir and Freundlich models allowed a good fit for experimental data. On the basis of the maximum adsorption capacity (qmax, the order affinity of Pb, Cu and Cd for the studied soil was Pb2+ > Cu2+ > Cd2+. Competitive sorption has proved that the competition between two or several cations on soils for the same active sites can decrease their qmax. These results show that, at high metal concentrations, Cd may pose more threat in soils and groundwater of Port-au-Prince than Pb and Cu.

  10. Assessing the mobility of lead, copper and cadmium in a calcareous soil of Port-au-Prince, Haiti.

    Science.gov (United States)

    Fifi, Urbain; Winiarski, Thierry; Emmanuel, Evens

    2013-11-04

    The presence of heavy metals in the environment constitutes a potential source of both soil and groundwater pollution. This study has focused on the reactivity of lead (Pb), copper (Cu) and Cadmium (Cd) during their transfer in a calcareous soil of Port-au-Prince (Haiti). Kinetic, monometal and competitive batch tests were carried out at pH 6.0. Two simplified models including pseudo-first-order and pseudo-second-order were used to fit the experimental data from kinetics adsorption batch tests. A good fit of these data was found with pseudo-second-order kinetic model which indicates the applicability of this model to describe the adsorption rates of these metals on the soil. Monometal batch tests indicated that both Langmuir and Freundlich models allowed a good fit for experimental data. On the basis of the maximum adsorption capacity (qmax), the order affinity of Pb, Cu and Cd for the studied soil was Pb2+ > Cu2+ > Cd2+. Competitive sorption has proved that the competition between two or several cations on soils for the same active sites can decrease their qmax. These results show that, at high metal concentrations, Cd may pose more threat in soils and groundwater of Port-au-Prince than Pb and Cu.

  11. Economic Design of Multi-echelon Inventory System with Variable Lead Time and Service Level Constraint in a Fuzzy Cost Environment

    Directory of Open Access Journals (Sweden)

    S. Priyan

    2016-12-01

    Full Text Available Normally, human based industrial decision making involves both quantitative and qualitative input factors such as ordering cost, setup cost, etc. Thus the practitioners should be careful in accounting flexibility in the input factors. This paper optimizes an inventory system by employing mathematical model with variable lead time and service level constraint (SLC in a fuzzy cost environment. Fuzziness is established by allowing the cost components imprecise and vague to certain extent. Trapezoidal and triangular fuzzy numbers are used to represent these characteristics. We also use signed distance method to defuzzify the fuzzy joint total expected cost and differential calculus optimization technique is adopted to find all optimal solutions to the model. Numerical results highlighting the sensitivity in the decision variables are also described.

  12. Assessment of atherosclerotic plaque inflammation can be improved by delayed time point FDG PET CT imaging

    DEFF Research Database (Denmark)

    Blomberg, Björn; Thomassen, Anders; Hildebrandt, Malene

    2013-01-01

    Objectives: Blood pool FDG activity can cloud the atherosclerotic plaque FDG signal. Over time, blood pool FDG activity declines. Therefore, delayed time point FDG PET CT imaging can potentially enhance the assessment of atherosclerotic plaque inflammation. Methods: Twelve healthy volunteers...... without traditional cardiovascular risk factors and three subjects with angina pectoris were prospectively assessed by dual time point 18-FDG PET CT imaging at 90 and 180 minutes after tracer injection. The ratio between aortic SUVmax and the blood pool SUVmean (TBR) was calculated to show the change......,35; df = 12; P = 0.037). Conclusions: Based on these preliminary data, we can make three conclusions: 1) aging and male gender are significantly correlated to atherosclerotic plaque FDG avidity, 2) over time, a significant increase is observed in TBR, and 3) the increase in cSUV over time results...

  13. Evaluating the Recovery Curve for Clinically Assessed Reaction Time After Concussion.

    Science.gov (United States)

    Del Rossi, Gianluca

    2017-08-01

      A change in reaction time is one of various clinical measures of neurocognitive function that can be monitored after concussion and has been reported to be among the most sensitive indicators of cognitive impairment.   To determine the timeline for clinically assessed simple reaction time to return to baseline after a concussion in high school athletes.   Observational study.   Athletic training room.   Twenty-one high school-aged volunteers.   Participants completed 8 trials of the ruler-drop test during each session. Along with baseline measures, a total of 6 additional test sessions were completed over the course of 4 weeks after a concussion (days 3, 7, 10, 14, 21, and 28).   The mean reaction times calculated for all participants from each of the 7 test sessions were analyzed to assess the change in reaction time over the 7 time intervals.   After a concussion and compared with baseline, simple reaction time was, on average, 26 milliseconds slower at 48 to 72 hours postinjury (P reaction time did not return to baseline levels until day 14 postinjury.   Clinically assessed simple reaction time appeared to return to baseline levels within a timeframe that mirrors other measures of cognitive performance (approximately 14 days).

  14. Factors influencing bolus dwell times in healthy older adults assessed endoscopically.

    Science.gov (United States)

    Butler, Susan G; Maslan, Jonathan; Stuart, Andrew; Leng, Xiaoyan; Wilhelm, Erika; Lintzenich, Catherine Rees; Williamson, Jeff; Kritchevsky, Stephen B

    2011-12-01

    Scant data exist on normal bolus dwell time assessed during flexible endoscopic evaluation of swallowing (FEES). The purpose of this study was to examine bolus dwell time in healthy older adults. Because it has been previously reported that some healthy older adults aspirate, we also sought to determine if bolus dwell time varied as a function of aspiration status. Prospective. Seventy-six healthy volunteers from the seventh, eighth, and ninth decades of life participated. Dwell times were analyzed via FEES as a function of pharyngeal location, liquid type, delivery method, purée type, viscosity, age, and gender. Longer dwell times were evidenced with the eldest participants, straw delivery, and the smallest volume. Adults in the ninth decade were 4.8 (P = .01) and 3.8 (P = .02) times more likely to have longer dwell times at the vallecula and 7.1 (P = .002) and 3.8 (P = 0.02) at the pyriform sinus than those in the seventh and eighth decades, respectively. Longer dwell times at the vallecula and pyriform sinuses were 2 and 2.38 times (P times (P dwell times than larger volumes. Bolus dwell times did not significantly differ as a function of aspiration status. Advanced age, straw delivery, and small volumes yielded longer dwell times. These variables should be considered before diagnosing an abnormal bolus dwell time in elder patients. Copyright © 2011 The American Laryngological, Rhinological, and Otological Society, Inc.

  15. 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.

  16. Arsenic, cadmium and lead in fresh and processed tuna marketed in Galicia (NW Spain): Risk assessment of dietary exposure.

    Science.gov (United States)

    Núñez, Ricardo; García, M Ángeles; Alonso, Julián; Melgar, M Julia

    2018-01-29

    Currently, metal bioaccumulation in fish is increasing and is a cause of concern due to toxicity. Total arsenic, cadmium and lead concentrations in fresh and processed tuna (110 samples) marketed in Galicia (NW Spain) were determined by ICP-MS spectrometry. The average concentrations of As and Cd, 3.78 and 0.024 mg kg -1 w.w., respectively, in fresh tuna were statistically significantly higher than those in processed tuna (p  natural > pickled sauce. Of the two species studied in canned tuna, Thunnus alalunga showed statistically significant higher levels both for As 1.28 mg kg -1 (p < 0.001) and Pb 0.013 mg kg -1 (p = 0.0496) than Thunnus albacares. No samples surpassed the limits set by the EU for Cd and Pb. The limit for As in fish has not been established, but the arsenic contents in fresh tuna reported here are important, as they are among the highest reported in the literature. Considering public health in children and adults with respect to the investigated metals, the estimated daily intakes (EDIs) did not exceed the tolerable intakes. No chronic systemic risk was found since all the target hazard quotients (THQs-TTHQs) were far below 1 (critical value), and the carcinogenic risk (CR) for As did not exceed the acceptable value of 10 -5 . Thus, tuna consumption in the Galician diet does not pose a risk for different population groups in terms of these studied metals/metalloids. Copyright © 2018. Published by Elsevier B.V.

  17. 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

  18. 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.

  19. Reduction of stroke assessment time for visually guided reaching task on KINARM exoskeleton robot.

    Science.gov (United States)

    Mostafavi, S M; Dukelow, S P; Glasgow, J I; Scott, S H; Mousavi, P

    2014-01-01

    Robotic technologies provide objective, highly reliable tools for assessment of brain function following stroke. KINARM is an exoskeleton device that quantifies sensorimotor brain function using a visually guided reaching task among many other behavioral tasks. As further tasks are developed to more broadly assess different aspects of behavior using the robot, techniques and approaches are required to reduce the time it takes to complete each task. The present study investigates how the value of robot-measured parameters changes under alternative schemes that significantly reduce assessment time compared to the current assessment protocol for the visually guided reaching task. Results of the study are validated by addressing an important diagnostic question using an SVM classifier, showing that the alternative schemes provide nearly identical performance in terms of classification sensitivity, specificity and accuracy.

  20. 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...... 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...... 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...

  1. 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.

  2. 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.

  3. A deposit model for Mississippi Valley-Type lead-zinc ores: Chapter A in Mineral deposit models for resource assessment

    Science.gov (United States)

    Leach, David L.; Taylor, Ryan D.; Fey, David L.; Diehl, Sharon F.; Saltus, Richard W.

    2010-01-01

    This report is a descriptive model of Mississippi Valley-Type (MVT) lead-zinc deposits that presents their geological, mineralogical and geochemical attributes and is part of an effort by the U.S. Geological Survey Mineral Resources Program to update existing models and develop new models that will be used for an upcoming national mineral resource assessment. This deposit modeling effort by the USGS is intended to supplement previously published models for use in mineral-resource and mineral-environmental assessments. Included in this report are geological, geophysical and geochemical assessment guides to assist in mineral resource estimation. The deposit attributes, including grade and tonnage of the deposits described in this report are based on a new mineral deposits data set of all known MVT deposits in the world.

  4. Contrast based real time assessment of microcirculatory changes in a fatty liver after ischemia reperfusion injury

    OpenAIRE

    Kolachala, Vasantha L.; Jiang, Rong; Abramowsky, Carlos R.; Gupta, Nitika A.

    2016-01-01

    A fatty liver is known to have impairment of microcirculation, which is worsened after ischemia reperfusion injury (IRI). This makes most fatty grafts unsuitable for transplantation, and in the absence of real time assessment of microcirculation this selection has been at best, random. The goal of this study was to demonstrate the utility of a contrast enhanced ultrasound model in quantitative assessment of the microcirculation of a fatty liver. We subjected fatty mice to IRI and blood flow d...

  5. A macroinvertebrate assessment of Ozark streams located in lead-zinc mining areas of the Viburnum Trend in southeastern Missouri, USA

    Science.gov (United States)

    Poulton, Barry C.; Allert, Ann L.; Besser, John M.; Schmitt, Christopher J.; Brumbaugh, William G.; Fairchild, James F.

    2010-01-01

    The Viburnum Trend lead-zinc mining subdistrict is located in the southeast Missouri portion of the Ozark Plateau. In 2003 and 2004, we assessed the ecological effects of mining in several watersheds in the region. We included macroinvertebrate surveys, habitat assessments, and analysis of metals in sediment, pore water, and aquatic biota. Macroinvertebrates were sampled at 21 sites to determine aquatic life impairment status (full, partial, or nonsupport) and relative biotic condition scores. Macroinvertebrate biotic condition scores were significantly correlated with cadmium, nickel, lead, zinc, and specific conductance in 2003 (r = -0.61 to -0.68) and with cadmium, lead, and pore water toxic units in 2004 (r = -0.55 to -0.57). Reference sites were fully supporting of aquatic life and had the lowest metals concentrations and among the highest biotic condition scores in both years. Sites directly downstream from mining and related activities were partially supporting, with biotic condition scores 10% to 58% lower than reference sites. Sites located greater distances downstream from mining activities had intermediate scores and concentrations of metals. Results indicate that elevated concentrations of metals originating from mining activities were the underlying cause of aquatic life impairment in several of the streams studied. There was general concurrence among the adversely affected sites in how the various indicators responded to mining activities during the overall study.

  6. 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....

  7. 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.

  8. Field assessment of treatment efficacy by three methods of phosphoric acid application in lead-contaminated urban soil.

    Science.gov (United States)

    Yang, John; Mosby, David

    2006-07-31

    In situ soil treatment using phosphoric acid (H(3)PO(4)) may be an effective remedial technology for immobilizing soil Pb and reducing Pb risk to human health and ecosystem. The treatment efficacy of three H(3)PO(4) application methods was assessed in a smelter-contaminated urban soil located in the Jasper County Superfund Site, Missouri. Soil, with an average of 3529 mg Pb kg(-1) and in the 2- by 4-m plot size, was treated with H(3)PO(4) at a rate of 10 g P kg(-1) in four replicates by each of three methods: rototilling; surface application; pressure injection. Three soil cores, 2.5-cm diameter and 30-cm long, were taken from each plot before and 90 days after treatment and analyzed for soluble P, bioaccessible Pb and solid-Pb speciation. Applications of H(3)PO(4) induced the heterogeneity of soluble P in soil, with the highest concentrations in the surface. Three application methods mixed the H(3)PO(4) more effectively in the horizontals than the verticals of treated soil zone. The H(3)PO(4) applications significantly reduced Pb bioaccessibility in the soil, which was influenced by the concentrations of soil soluble P and solid-Pb species. The risk reductions of soil Pb were achieved by formation of pyromorphites or pyromorphite-like minerals. The rototilling appears to be the most effective treatment method in context of the homogeneity of soluble P and the reduction of Pb bioaccessibility in treated soil.

  9. Risk assessment of lead poisoning and pesticide exposure in the declining population of red-breasted goose (Branta ruficollis) wintering in Eastern Europe

    OpenAIRE

    Mateo, Rafael; Petkov, Nikolai; Lopez-Antia, Ana; Rodriguez-Estival, Jaime; Green, Andy J.

    2016-01-01

    Abstract: The red-breasted goose Branta ruficollis is a globally threatened species (IUCN Vulnerable) and the only European goose species currently in decline. Working on the wintering grounds on the Black Sea Coast, we address two potential causes of decline of this species for the first time: lead poisoning, and contamination from pesticides. We quantified the densities of spent Pb shot in three wetlands used by the geese in north-east Bulgaria, and analysed the Pb concentration in the faec...

  10. Glutamate-induced obesity leads to decreased sperm reserves and acceleration of transit time in the epididymis of adult male rats

    Directory of Open Access Journals (Sweden)

    Fernandes Glaura SA

    2012-12-01

    Full Text Available Abstract Background Given the established fact that obesity interferes with male reproductive functions, the present study aimed to evaluate sperm production in the testis and storage in the epididymis in a glutamate-induced model of obesity. Methods Male rats were treated neonatally with monosodium glutamate (MSG at doses of 4 mg/kg subcutaneously, or with saline solution (control group, on postnatal days 2, 4, 6, 8 and 10. On day 120, obesity was confirmed by the Lee index in all MSG-treated rats. After this, all animals from the two experimental groups were anesthetized and killed to evaluate body and reproductive organ weights, sperm parameters, plasma hormone levels (FSH, LH and testosterone, testicular and epididymal histo-morphometry and histopathology. Results Significant reductions in absolute and relative weights of testis, epididymis, prostate and seminal vesicle were noted in MSG-treated animals. In these same animals plasma testosterone and follicle-stimulating hormone (FSH concentrations were decreased, as well as sperm counts in the testis and epididymis and seminiferous epithelium height and tubular diameter. The sperm transit time was accelerated in obese rats. However, the number of Sertoli cells per seminiferous tubule and stereological findings on the epididymis were not markedly changed by obesity. Conclusions Neonatal MSG-administered model of obesity lowers sperm production and leads to a reduction in sperm storage in the epididymis of adult male rats. The acceleration of sperm transit time can have implications for the sperm quality of these rats.

  11. Nutrient leaching, soil pH and changes in microbial community increase with time in lead-contaminated boreal forest soil at a shooting range area.

    Science.gov (United States)

    Selonen, Salla; Setälä, Heikki

    2017-02-01

    Despite the known toxicity of lead (Pb), Pb pellets are widely used at shotgun shooting ranges over the world. However, the impacts of Pb on soil nutrients and soil microbes, playing a crucial role in nutrient cycling, are poorly understood. Furthermore, it is unknown whether these impacts change with time after the cessation of shooting. To shed light on these issues, three study sites in the same coniferous forest in a shooting range area were studied: an uncontaminated control site and an active and an abandoned shooting range, both sharing a similar Pb pellet load in the soil, but the latter with a 20-year longer contamination history. Soil pH and nitrate concentration increased, whilst soil phosphate concentration and fungal phospholipid fatty acid (PLFA) decreased due to Pb contamination. Our results imply that shooting-derived Pb can influence soil nutrients and microbes not only directly but also indirectly by increasing soil pH. However, these mechanisms cannot be differentiated here. Many of the Pb-induced changes were most pronounced at the abandoned range, and nutrient leaching was increased only at that site. These results suggest that Pb disturbs the structure and functions of the soil system and impairs a crucial ecosystem service, the ability to retain nutrients. Furthermore, the risks of shooting-derived Pb to the environment increase with time.

  12. Lifetime, mobility, and diffusion of photoexcited carriers in ligand-exchanged lead selenide nanocrystal films measured by time-resolved terahertz spectroscopy.

    Science.gov (United States)

    Guglietta, Glenn W; Diroll, Benjamin T; Gaulding, E Ashley; Fordham, Julia L; Li, Siming; Murray, Christopher B; Baxter, Jason B

    2015-02-24

    Colloidal semiconductor nanocrystals have been used as building blocks for electronic and optoelectronic devices ranging from field-effect transistors to solar cells. Properties of the nanocrystal films depend sensitively on the choice of capping ligand to replace the insulating synthesis ligands. Thus far, ligands leading to the best performance in transistors result in poor solar cell performance, and vice versa. To gain insight into the nature of this dichotomy, we used time-resolved terahertz spectroscopy measurements to study the mobility and lifetime of PbSe nanocrystal films prepared with five common ligand-exchange reagents. Noncontact terahertz spectroscopy measurements of conductivity were corroborated by contacted van der Pauw measurements of the same samples. The films treated with different displacing ligands show more than an order of magnitude difference in the peak conductivities and a bifurcation of time dynamics. Inorganic chalcogenide ligand exchanges with sodium sulfide (Na2S) or ammonium thiocyanate (NH4SCN) show high mobilities but nearly complete decay of transient photocurrent in 1.4 ns. In contrast, ligand exchanges with 1,2-ethylenediamine (EDA), 1,2-ethanedithiol (EDT), and tetrabutylammonium iodide (TBAI) show lower mobilities but longer carrier lifetimes, resulting in longer diffusion lengths. This bifurcated behavior may explain the divergent performance of field-effect transistors and photovoltaics constructed from nanocrystal building blocks with different ligand exchanges.

  13. The Use of Operational Short and Long Lead-time Hydrologic Forecasts by Water Resources Decision Makers in the Ohio River Valley

    Science.gov (United States)

    Adams, T. E.

    2012-12-01

    The need for hydroclimatic forecasts for water resources systems operations is significant and is clearly growing. Hydroclimatic forecasts consist of two components: first, forecasts of hydrometeorological forcings used to drive hydrologic models and, second, the resulting streamflow and stage forecasts or derivative quantities, such as reservoir inflow volumes or time above (or below) some threshold value. These forecast range from hourly to annual lead-times and include both deterministic and probabilistic formats. In the Ohio River Valley, forecasts are made available by the NOAA/NWS Ohio River Forecast Center to decision makers. These include the general public, local and state emergency managers and other officials, federal agencies, utilities, the navigation industry, and agricultural sector, and others. Hydrologic forecasts are utilized by end-users for widely varying purposes including flood warning and mitigation, reservoir management, and decision making for construction projects, to name a few. This paper will illustrate the range of NWS hydrologic streamflow and stage products that are made publicly available and how some of the forecasts are used during drought or low-flow periods and during episodes of flooding. The methodologies used to generate hydroclimatic forecasts and the complexities found in large-scale operational systems and their impact on forecast robustness will also be discussed.

  14. Survey of temperature, reaction time and ultrasound irradiation power on sonochemical synthesis of two new nanostructured lead(II) coordination supramolecule compounds.

    Science.gov (United States)

    Hayati, Payam; Rezvani, AliReza; Morsali, Ali; Retailleau, Pascal; Centore, Roberto

    2017-03-01

    Nanoparticles of two new 0D, lead(II) coordination supramolecular compounds, [Pb(L)2(I)2] (1) and [Pb(L)(L(/))(H2O)]·3H2O (2), (L=1,10-phenanthroline monohydrate, L(/)=2,6-pyridinedicarboxlic acid), have been synthesized by a sonochemical process and characterized by scanning electron microscopy (SEM), field emission scanning electron microscopy (FE-SEM), X-ray powder diffraction (XRPD), FT-IR spectroscopy and elemental analyses. The single crystal X-ray data of compounds show that the Pb ion is six coordinated in both 1 and 2. The thermal stability of compound 1 and 2 has been studied by thermal gravimetric (TG) and differential thermal analyses (DTA). The role of temperature, reaction time and ultrasound irradiation power on the size and morphology of the nano-structured compound obtained from 1 and 2, have been investigated. Results indicate that an increase of temperature and sonication power and a decrease in time reaction led to a decrease of particle size. Topological analysis shows that the compound 1 and 2 are new topology for net: 1,4M5-1 and nch, respectively. Copyright © 2016 Elsevier B.V. All rights reserved.

  15. Challenges to time trade-off utility assessment methods: when should you consider alternative approaches?

    Science.gov (United States)

    Boye, Kristina S; Matza, Louis S; Feeny, David H; Johnston, Joseph A; Bowman, Lee; Jordan, Jessica B

    2014-06-01

    In recent years, the time trade-off (TTO) method, most commonly with a 10-year time horizon, has been the most frequently used approach for direct health state utility assessment, likely due to National Institute for Health and Care Excellence (NICE) preference for comparability with the EQ-5D, which has a utility scoring algorithm derived via this method. Although comparability to previous utility studies is important, there are situations when the TTO method may not be appropriate. The purpose of the current review is to highlight challenges to the TTO method. Five challenges to the TTO method are discussed: mild health states, small differences among health states, temporary health states, pediatric health states, and assessment of samples with particular characteristics. Some of these challenges are associated with the 10-year time horizon, while other situations may raise issues for TTO methods regardless of the time horizon. Alternative approaches for valuing health states are suggested.

  16. 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

  17. Multi-step constant-current charging method for electric vehicle, valve-regulated, lead/acid batteries during night time for load-levelling

    Energy Technology Data Exchange (ETDEWEB)

    Ikeya, Tomohiko; Mita, Yuichi; Ishihara, Kaoru [Central Research Inst. of Electric Power Industry, Tokyo (Japan); Sawada, Nobuyuki [Hokkaido Electric Power, Sapporo (Japan); Takagi, Sakae; Murakami, Jun-ichi [Tohoku Electric Power, Sendai (Japan); Kobayashi, Kazuyuki [Tokyo Electric Power, Yokohama (Japan); Sakabe, Tetsuya [Chubu Electric Power, Nagoya (Japan); Kousaka, Eiichi [Hokuriku Electric Power, Toyama (Japan); Yoshioka, Haruki [The Kansai Electric Power, Osaka (Japan); Kato, Satoru [The Chugoku Electric Power, Hiroshima (Japan); Yamashita, Masanori [Shikoku Research Inst., Takamatsu (Japan); Narisoko, Hayato [The Okinawa Electric Power, Naha (Japan); Nishiyama, Kazuo [The Central Electric Power Council, Tokyo (Japan); Adachi, Kazuyuki [Kyushu Electric Power, Fukuoka (Japan)

    1998-09-01

    For the popularization of electric vehicles (EVs), the conditions for charging EV batteries with available current patterns should allow complete charging in a short time, i.e., less than 5 to 8 h. Therefore, in this study, a new charging condition is investigated for the EV valve-regulated lead/acid battery system, which should allow complete charging of EV battery systems with multi-step constant currents in a much shorter time with longer cycle life and higher energy efficiency compared with two-step constant-current charging. Although a high magnitude of the first current in the two-step constant-current method prolongs cycle life by suppressing the softening of positive active material, too large a charging current magnitude degrades cells due to excess internal evolution of heat. A charging current magnitude of approximately 0.5 C is expected to prolong cycle life further. Three-step charging could also increase the magnitude of charging current in the first step without shortening cycle life. Four-or six-step constant-current methods could shorten the charging time to less than 5 h, as well as yield higher energy efficiency and enhanced cycle life of over 400 cycles compared with two-step charging with the first step current of 0.5 C. Investigation of the degradation mechanism of the batteries revealed that the conditions of multi-step constant-current charging suppressed softening of positive active material and sulfation of negative active material, but, unfortunately, advanced the corrosion of the grids in the positive plates. By adopting improved grids and cooling of the battery system, the multistep constant-current method may enhance the cycle life. (orig.)

  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

    2017-09-07

    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. Priority assessment of toxic substances in life cycle assessment. III: Export of potential impact over time and space.

    Science.gov (United States)

    Huijbregts, M A; Guinée, J B; Reijnders, L

    2001-07-01

    Toxicity potentials are scaling factors used in life cycle assessment (LCA) indicating their relative importance in terms of potential toxic impacts. This paper presents the results of an uncertainty assessment of toxicity potentials for 181 substances that were calculated with the global nested multi-media fate, exposure and effects model USES-LCA. The variance in toxicity potentials resulting from choices in the modelling procedure was quantified by means of scenario analysis. A first scenario analysis showed to what extent potential impacts in the relatively short term are obscured by the inclusion of impacts on the very long term. Toxicity potentials representing potential impacts over time horizons of 20, 100 and 500 years were compared with toxicity potentials representing potential impacts over an infinite time horizon. Time horizon dependent differences up to 6.5 orders of magnitude were found for metal toxicity potentials, while for toxicity potentials of organic substances under study, differences remain within 0.5 orders of magnitude. The second scenario analysis addressed to what extent potential impacts on the continental scale are obscured by the inclusion of impacts on the global scale. Exclusion of potential impacts on the global scale changed the toxicity potentials of metals and volatile persistent halogenated organics up to 2.3 orders of magnitude. These scenario analyses also provide the basis for determining exports to future generations and outside the emission area.

  20. Assessing meaningful change in quality of life over time: A users' guide for clinicians

    NARCIS (Netherlands)

    Sprangers, Mirjam A. G.; Moinpour, Carol M.; Moynihan, Timothy J.; Patrick, Donald L.; Revicki, Dennis A.

    2002-01-01

    The objective of this article is to help clinicians interpret trial-based quality of life (QOL) changes over time. We address a series of questions and provide guidelines that are fundamental to assessing and interpreting change. The issues addressed are as follows: (1) What are the characteristics

  1. Time on Test, Student Motivation, and Performance on the Collegiate Learning Assessment: Implications for Institutional Accountability

    Science.gov (United States)

    Hosch, Braden J.

    2010-01-01

    Using results from the Collegiate Learning Assessment (CLA) administered at Central Connecticut State University, a public Carnegie master's-larger programs university in the Northeast, this study demonstrates time on spent on the test, student motivation, and to a lesser extent the local institutional administration procedures represent…

  2. Detecting Probable Cheating during Online Assessments Based on Time Delay and Head Pose

    Science.gov (United States)

    Chuang, Chia Yuan; Craig, Scotty D.; Femiani, John

    2017-01-01

    This study investigated the ability of test takers' behaviors during online assessments to detect probable cheating incidents. Specifically, this study focused on the role of time delay and head pose for detection of cheating incidences in a lab-based online testing session. The analysis of a test taker's behavior indicated that not only time…

  3. 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.

  4. Time-varying disaster risk models: An empirical assessment of the Rietz-Barro hypothesis

    DEFF Research Database (Denmark)

    Irarrazabal, Alfonso; Parra-Alvarez, Juan Carlos

    This paper revisits the fit of disaster risk models where a representative agent has recursive preferences and the probability of a macroeconomic disaster changes over time. We calibrate the model as in Wachter (2013) and perform two sets of tests to assess the empirical performance of the model...

  5. Diffuse reflectance spectroscopy as a tool for real-time tissue assessment during colorectal cancer surgery

    NARCIS (Netherlands)

    Baltussen, Elisabeth J.M.; Snaebjornsson, Petur; De Koning, Susan G.Brouwer; Sterenborg, Henricus J.C.M.; Aalbers, Arend G.J.; Kok, Niels; Beets, Geerard L.; Hendriks, Benno H.W.; Kuhlmann, Koert F.D.; Ruers, Theo J.M.

    2017-01-01

    © 2017 Society of Photo-Optical Instrumentation Engineers (SPIE). Colorectal surgery is the standard treatment for patients with colorectal cancer. To overcome two of the main challenges, the circumferential resection margin and postoperative complications, real-time tissue assessment could be of

  6. Assessment of intraventricular time differences in healthy children using two-dimensional speckle-tracking echocardiography

    NARCIS (Netherlands)

    Klitsie, Liselotte M.; Roest, Arno A. W.; van der Hulst, Annelies E.; Stijnen, Theo; Blom, Nico A.; ten Harkel, Arend D. J.

    2013-01-01

    Parameters describing intraventricular time differences are increasingly assessed in both adults and children. However, to appreciate the implications of these parameters in children, knowledge of the applicability of adult techniques in children is essential. Hence, the aim of this study was to

  7. Assessing Hospital Disaster Readiness Over Time at the US Department of Veterans Affairs.

    Science.gov (United States)

    Der-Martirosian, Claudia; Radcliff, Tiffany A; Gable, Alicia R; Riopelle, Deborah; Hagigi, Farhad A; Brewster, Pete; Dobalian, Aram

    2017-02-01

    Introduction There have been numerous initiatives by government and private organizations to help hospitals become better prepared for major disasters and public health emergencies. This study reports on efforts by the US Department of Veterans Affairs (VA), Veterans Health Administration, Office of Emergency Management's (OEM) Comprehensive Emergency Management Program (CEMP) to assess the readiness of VA Medical Centers (VAMCs) across the nation. Hypothesis/Problem This study conducts descriptive analyses of preparedness assessments of VAMCs and examines change in hospital readiness over time. To assess change, quantitative analyses of data from two phases of preparedness assessments (Phase I: 2008-2010; Phase II: 2011-2013) at 137 VAMCs were conducted using 61 unique capabilities assessed during the two phases. The initial five-point Likert-like scale used to rate each capability was collapsed into a dichotomous variable: "not-developed=0" versus "developed=1." To describe changes in preparedness over time, four new categories were created from the Phase I and Phase II dichotomous variables: (1) rated developed in both phases; (2) rated not-developed in Phase I but rated developed in Phase II; (3) rated not-developed in both phases; and (4) rated developed in Phase I but rated not- developed in Phase II. From a total of 61 unique emergency preparedness capabilities, 33 items achieved the desired outcome - they were rated either "developed in both phases" or "became developed" in Phase II for at least 80% of VAMCs. For 14 items, 70%-80% of VAMCs achieved the desired outcome. The remaining 14 items were identified as "low-performing" capabilities, defined as less than 70% of VAMCs achieved the desired outcome. Measuring emergency management capabilities is a necessary first step to improving those capabilities. Furthermore, assessing hospital readiness over time and creating robust hospital readiness assessment tools can help hospitals make informed decisions

  8. Lead Toxicity

    Science.gov (United States)

    ... blue-gray metal that is mined from the earth’s crust. • Lead has been used for many industrial ... including the kidneys, heart, and reproductive system, • Pregnant women should know that the developing fetus is very ...

  9. Lead Poisoning

    Science.gov (United States)

    ... has also been associated with juvenile delinquency and criminal behavior. In adults, lead can increase blood pressure ... and-forth manner, but rather from left to right (or vise-versa), or from the top of ...

  10. Lead Test

    Science.gov (United States)

    ... poison you. Most lead is present as an inorganic compound and does not move well through the ... D. R., Editors (© 2006). Contemporary Practice in Clinical Chemistry: AACC Press, Washington, DC. Pp 474. Wu, A. (© ...

  11. Analysis of domestic refrigerator temperatures and home storage time distributions for shelf-life studies and food safety risk assessment.

    Science.gov (United States)

    Roccato, Anna; Uyttendaele, Mieke; Membré, Jeanne-Marie

    2017-06-01

    In the framework of food safety, when mimicking the consumer phase, the storage time and temperature used are mainly considered as single point estimates instead of probability distributions. This singlepoint approach does not take into account the variability within a population and could lead to an overestimation of the parameters. Therefore, the aim of this study was to analyse data on domestic refrigerator temperatures and storage times of chilled food in European countries in order to draw general rules which could be used either in shelf-life testing or risk assessment. In relation to domestic refrigerator temperatures, 15 studies provided pertinent data. Twelve studies presented normal distributions, according to the authors or from the data fitted into distributions. Analysis of temperature distributions revealed that the countries were separated into two groups: northern European countries and southern European countries. The overall variability of European domestic refrigerators is described by a normal distribution: N (7.0, 2.7)°C for southern countries, and, N (6.1, 2.8)°C for the northern countries. Concerning storage times, seven papers were pertinent. Analysis indicated that the storage time was likely to end in the first days or weeks (depending on the product use-by-date) after purchase. Data fitting showed the exponential distribution was the most appropriate distribution to describe the time that food spent at consumer's place. The storage time was described by an exponential distribution corresponding to the use-by date period divided by 4. In conclusion, knowing that collecting data is time and money consuming, in the absence of data, and at least for the European market and for refrigerated products, building a domestic refrigerator temperature distribution using a Normal law and a time-to-consumption distribution using an Exponential law would be appropriate. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. The euglobulin clot lysis time to assess the impact of nanoparticles on fibrinolysis

    Science.gov (United States)

    Minet, Valentine; Alpan, Lutfiye; Mullier, François; Toussaint, Olivier; Lucas, Stéphane; Dogné, Jean-Michel; Laloy, Julie

    2015-07-01

    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.

  13. 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.

  14. Redução do lead time e entregas no prazo em pequenas e médias empresas que fabricam sob encomenda: a abordagem Worload Control (WLC para o Planejamento e Controle da Produção (PCP Lead time reduction and improved tardiness performance in small and medium sized Make-to-Order Companies: the Workload Control (WLC approach, a solution for Production Planning and Control (PPC

    Directory of Open Access Journals (Sweden)

    Matthias Thurer

    2012-01-01

    designed for small sized Make-to-Order companies. According to the literature, such approach has the potential to reduce lead time, work in process, and to provide a better tardiness performance in MTO companies. Firstly, the paper presents the WLC approach reviewing and discussing the main WLC aspects addressed in the literature. The objective is to introduce the concept and present the recent developments to fellow researchers and practitioners. The performance of WLC is then assessed by simulation. The results underline the potential of WLC to bring major improvements in terms of lead time and tardiness performance supporting small and medium sized MTO companies. Therefore, this study aims at contributing to PPC academic and practical areas by introducing WLC approach concepts to Brazilian researchers and managers showing its benefits and potential to help national companies in their efforts towards lead time reduction and best tardiness performance according to modern manufacturing paradigms such as Lean Manufacturing and Quick Response Manufacturing.

  15. Cochrane Rapid Reviews Methods Group to play a leading role in guiding the production of informed high-quality, timely research evidence syntheses

    Directory of Open Access Journals (Sweden)

    Chantelle Garritty

    2016-10-01

    Full Text Available Abstract Background 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. Purpose 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. Conclusion 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

  16. Office workers' objectively assessed total and prolonged sitting time: Individual-level correlates and worksite variations

    Directory of Open Access Journals (Sweden)

    Nyssa T. Hadgraft

    2016-12-01

    Full Text Available Sedentary behavior is highly prevalent in office-based workplaces; however, few studies have assessed the attributes associated with this health risk factor in the workplace setting. This study aimed to identify the correlates of office workers' objectively-assessed total and prolonged (≥30 min bouts workplace sitting time. Participants were 231 Australian office workers recruited from 14 sites of a single government employer in 2012–13. Potential socio-demographic, work-related, health-related and cognitive-social correlates were measured through a self-administered survey and anthropometric measurements. Associations with total and prolonged workplace sitting time (measured with the activPAL3 were tested using linear mixed models. Worksites varied significantly in total workplace sitting time (overall mean [SD]: 79% [10%] of work hours and prolonged workplace sitting time (42% [19%], after adjusting for socio-demographic and work-related characteristics. Organisational tenure of 3–5 years (compared to tenure >5 years was associated with more time spent in total and prolonged workplace sitting time, while having a BMI categorised as obese (compared to a healthy BMI was associated with less time spent in total and prolonged workplace sitting time. Significant variations in sitting time were observed across different worksites of the same employer and the variation remained after adjusting for individual-level factors. Only BMI and organisational tenure were identified as correlates of total and prolonged workplace sitting time. Additional studies are needed to confirm the present findings across diverse organisations and occupations.

  17. [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.

  18. A longitudinal assessment of occupation, respiratory symptoms, and blood lead levels among latino day laborers in a non-agricultural setting.

    Science.gov (United States)

    Rabito, Felicia A; Perry, Sara; Salinas, Oscar; Hembling, John; Schmidt, Norine; Parsons, Patrick J; Kissinger, Patricia

    2011-05-01

    The reliance on Latino migrant day labor in the U.S. is increasing. Prospective data on day laborers' work and health experience in non-agriculture settings are lacking and outcomes are generally restricted to injury rates. An ambidirectional study was conducted to quantify the number of job and job task changes held over 12 months in a cohort of 73 migrant day laborers and assessed the relation between work type, health symptoms, and blood lead level. On average, participants worked 2.4 different jobs over the past year averaging 41.5 hr per week. Construction work was associated with a twofold increase in sino-nasal and respiratory symptoms in both adjusted and unadjusted models and was associated with increased blood lead levels. Despite day labor status, workers had relatively stable employment. Respiratory symptoms were common and often improved when away from work suggesting that workplace irritant exposure is likely. Migrant day laborers working construction are vulnerable to adverse health effects associated with irritant and lead exposure. Copyright © 2010 Wiley-Liss, Inc.

  19. Live/real time three-dimensional transthoracic echocardiographic assessment of Ebstein's anomaly.

    Science.gov (United States)

    Patel, Vinod; Nanda, Navin C; Rajdev, Sanjay; Mehmood, Farhat; Velayudhan, Dasan; Vengala, Srinivas; Copeland, Robert B; Madadi, Pavan

    2005-11-01

    We describe our experience in using live/real time three-dimensional transthoracic echocardiography (3D TTE) in the assessment of five adult patients with Ebstein's anomaly. The technique was found useful in assessing the distribution and extent of tethering of each of the three leaflets of the tricuspid valve (TV) to the underlying right ventricular walls and the ventricular septum. The characteristic bubble-like appearance resulting from bulging of the non-tethered areas of the TV leaflets was also well visualized in three dimensions and their size measured. Thus, an estimate of the nontethered or free segments of all three leaflets of the TV could be obtained using this technique. This has important implications when considering these patients for surgical repair of the TV. Visualization of all three leaflets of the TV and their extent of tethering by 3D TTE also made it easier to identify the boundaries of the functioning right ventricular chamber potentially providing a more reliable assessment of its volumes and ejection fraction. Cropping of color Doppler 3D TTE data sets provided en face viewing of the TV regurgitation vena contracta permitting accurate assessment of its shape and size. This has the potential to provide a more accurate quantitative estimation of TV regurgitation severity as compared to two-dimensional color Doppler. In conclusion, live/real time 3D TTE appears useful in supplementing two-dimensional echocardiography in more comprehensively assessing the morphologic features of Ebstein's anomaly.

  20. 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.

  1. Assessment of Smolt Condition for Travel Time Analysis, 1991-1992 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Maule, Alec G.; Beeman, John W.; Schrock, Robin M. (Seattle National Fishery Research Center, Columbia River Field Station, Cook, WA)

    1994-05-01

    Regression techniques were used to determine the effects of several biotic and abiotic variables on the migration rates of juvenile spring chinook salmon and steelhead in the Columbia and Snake rivers. Comparisons of the effects of river flow and smoltification, assessed using gill Na{sup +}-K{sup +} ATPase activity, were of primary interest. Day of the year, water temperature, change in flow, condition factor, and fork length were also considered as independent variables. Groups of fish were sampled to assess smoltification 2-3 times per week during the spring outmigrations during 1989-1992. These groups were assumed to be representative of other fish which were PIT-tagged and released as a part of the Smolt Monitoring Program in the Columbia Basin. River flow, gill ATPase activity, condition factor, water temperature, and change in flow were significant variables in regressions predicting the time for juvenile spring chinook salmon to travel between specific points (travel time), whereas river flow was the only significant contributor to models describing travel times of steelhead. Predicted travel times of wild steelhead were shorter than those of hatchery steelhead. River flow was the only variable common to all regression equations. Based on the characteristic, changes in river flow would be the most logical means to decrease travel times of both juvenile spring chinook salmon and steelhead in the Columbia and Snake rivers.

  2. PREDICTOR VALIDITY OF MORPHOLOGICAL AND BASIC MOTOR VARIABLES FOR ASSESSMENT AND MONITORING OF THE KARATE PUNCH WITH THE LEAD ARM (OI-TSUKI

    Directory of Open Access Journals (Sweden)

    D.V. Doder

    2011-11-01

    Full Text Available The purpose of this study was to determine the influence of morphological and basic motor variables on the karate forward punch (oi tsuki as the only criterion variable, and secondly, to design a test battery for the assessment and monitoring of boys in karate, based on the predictive validity of the tested variables. A system of 25 variables in total – 12 morphological, 12 basic motor (the system of predictor variables and 1 variable of situational moving structure (criterion variable, i.e. the karate punch with the lead arm (oi-tsuki – was applied on a sample of 82 karate trainees aged between 10 and 14. The results of regression analysis showed that a system of morphological and basic motor variables had a significant impact on punching with the lead arm (p<0.01. The stepwise method identified the largest individual value in the case of morphological variables of arm length, upper arm skinfold and body mass at the level of significance p<0.01, whereas basic motor variables (long jump from a standing start and half squat with weight also have a level of significance p<0.01. This shows that respondents with longer arms, less subcutaneous fat tissue on the upper arm, higher body mass and greater static and explosive strength of the lower extremities achieve better results. Determining predictor validity by regression analysis and the stepwise method is employed in order to diagnose, assess, monitor and evaluate the direct punch with the lead arm, so the next battery of measurement instruments can be constructed: arm length, upper arm skinfold, body mass, half squat with weight, long jump from a standing position.

  3. 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.

  4. 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?

  5. Time-dependent influence on assessment of contaminated environmental surfaces in operating rooms.

    Science.gov (United States)

    Saito, Yuhei; Yasuhara, Hiroshi; Murakoshi, Satoshi; Komatsu, Takami; Fukatsu, Kazuhiko; Uetera, Yushi

    2015-09-01

    There is no established method to assess the contamination of environmental surfaces because the results change with time. We evaluated current methods for assessment of contamination of environmental surfaces in the operating room (OR). Contamination of environmental surfaces in the OR was assessed using an adenosine triphosphate (ATP) test and bacterial culture. We collected 480 ATP test samples from 17 surfaces in 6 ORs to determine the influence of surface features, including frequency of touching and surface orientation on contamination, after completion of daily scheduled operations. Another 54 pairs of ATP and microbial samples were taken from 3 surfaces in each of the same OR except 1 to determine the time course of the results of ATP and microbial tests when ORs were not used. Multivariate analysis demonstrated that the ATP results were strongly influenced by frequency of touching and orientation of environmental surfaces. The microbial counts declined over time, whereas the ATP results remained at a high level. The ATP test result could be used as a relatively stable trace of contamination of environmental surfaces; however, it is not a surrogate indicator of the number of viable microbes which declines over time. Copyright © 2015 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved.

  6. Brain radiation injury leads to a dose- and time-dependent recruitment of peripheral myeloid cells that depends on CCR2 signaling.

    Science.gov (United States)

    Moravan, Michael J; Olschowka, John A; Williams, Jacqueline P; O'Banion, M Kerry

    2016-02-03

    Cranial radiotherapy is used to treat tumors of the central nervous system (CNS), as well as non-neoplastic conditions such as arterio-venous malformations; however, its use is limited by the tolerance of adjacent normal CNS tissue, which can lead to devastating long-term sequelae for patients. Despite decades of research, the underlying mechanisms by which radiation induces CNS tissue injury remain unclear. Neuroinflammation and immune cell infiltration are a recognized component of the CNS radiation response; however, the extent and mechanisms by which bone marrow-derived (BMD) immune cells participate in late radiation injury is unknown. Thus, we set out to better characterize the response and tested the hypothesis that C-C chemokine receptor type 2 (CCR2) signaling was required for myeloid cell recruitment following brain irradiation. We used young adult C57BL/6 male bone marrow chimeric mice created with donor mice that constitutively express enhanced green fluorescent protein (eGFP). The head was shielded to avoid brain radiation exposure during chimera construction. Radiation dose and time response studies were conducted in wild-type chimeras, and additional experiments were performed with chimeras created using donor marrow from CCR2 deficient, eGFP-expressing mice. Infiltrating eGFP+ cells were identified and quantified using immunofluorescent microscopy. Brain irradiation resulted in a dose- and time-dependent infiltration of BMD immune cells (predominately myeloid) that began at 1 month and persisted until 6 months following ≥15 Gy brain irradiation. Infiltration was limited to areas that were directly exposed to radiation. CCR2 signaling loss resulted in decreased numbers of infiltrating cells at 6 months that appeared to be restricted to cells also expressing major histocompatibility complex class II molecules. The potential roles played by infiltrating immune cells are of current importance due to increasing interest in immunotherapeutic approaches

  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. 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.

  9. 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.

  10. Visual assessment of breast density using Visual Analogue Scales: observer variability, reader attributes and reading time

    Science.gov (United States)

    Ang, Teri; Harkness, Elaine F.; Maxwell, Anthony J.; Lim, Yit Y.; Emsley, Richard; Howell, Anthony; Evans, D. Gareth; Astley, Susan; Gadde, Soujanya

    2017-03-01

    Breast density is a strong risk factor for breast cancer and has potential use in breast cancer risk prediction, with subjective methods of density assessment providing a strong relationship with the development of breast cancer. This study aims to assess intra- and inter-observer variability in visual density assessment recorded on Visual Analogue Scales (VAS) among trained readers, and examine whether reader age, gender and experience are associated with assessed density. Eleven readers estimated the breast density of 120 mammograms on two occasions 3 years apart using VAS. Intra- and inter-observer agreement was assessed with Intraclass Correlation Coefficient (ICC) and variation between readers visualised on Bland-Altman plots. The mean scores of all mammograms per reader were used to analyse the effect of reader attributes on assessed density. Excellent intra-observer agreement (ICC>0.80) was found in the majority of the readers. All but one reader had a mean difference of gender, or with reading time. Overall, the readers were consistent in their scores, although some large variations were observed. Reader evaluation and targeted training may alleviate this problem.

  11. Estimation of time-varying selectivity in stock assessments using state-space models

    DEFF Research Database (Denmark)

    Nielsen, Anders; Berg, Casper Willestofte

    2014-01-01

    -varying selectivity pattern. The fishing mortality rates are considered (possibly correlated) stochastic processes, and the corresponding process variances are estimated within the model. The model is applied to North Sea cod and it is verified from simulations that time-varying selectivity can be estimated......Time-varying selectivity is one of the main challenges in single species age-based assessment models. In classical deterministic VPA-type models the fishing mortality rates are unfiltered representations of the observed catches. As a consequence the selectivity becomes time......-varying, but this representation is too fluctuating, because it includes the observation noise. In parametric statistical catch at age models a common assumption is that the selectivity is constant in all years, although time-varying selectivity can be introduced by splitting the data period in blocks with different selectivities...

  12. The leak location package for assessment of the time-frequency correlation method for leak location

    Science.gov (United States)

    Faerman, V. A.; Cheremnov, A. G.; Avramchuk, V. S.; Shepetovsky, D. V.

    2017-01-01

    The paper describes the simplest implementation of a software and hardware package for acoustic correlation leak location and results of its performance assessment for location of water leaks from a metallic pipe in laboratory conditions. A distinctive feature of this leak locator is the use of the software based on the time-frequency correlation analysis of signals, which was proposed in our previous papers. Comparative analysis results are given for the information content of classical and time-frequency cross-correlation functions as obtained during processing of experimental data. The results obtained justify comparatively higher efficiency of a time-frequency cross correlation method to solve the leak location task. Improved efficiency is determined by bandpass filtration embedded into the time-frequency cross-correlation function calculation.

  13. 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...

  14. Bearing performance degradation assessment based on time-frequency code features and SOM network

    Science.gov (United States)

    Zhang, Yan; Tang, Baoping; Han, Yan; Deng, Lei

    2017-04-01

    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.

  15. 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.

  16. Assessment of real time traffic noise attenuation by tree belts within Kolkata city (India).

    Science.gov (United States)

    Ghosh, Dipak; Lahiri, Madhumita Banerjee; Tudu, Bharati; Deb, Argha; Majumder, Ashis; Bose, Asok Nath; Chakrabarty, Debashis

    2012-07-01

    The study of the existing scenario of the effect of trees and shrubs as urban screen plantings for abating the level of real time traffic-induced noise pollution in Kolkata city deserves extreme importance. However, no such data are available till date in this area. This paper reports the result of a preliminary study to assess the attenuation of real time traffic noise by tree belts at three different important locations of the city. This measurement provides some new and interesting data which will be useful for further study and subsequent plan.

  17. Real-Time Assessment of Robot Performance During Remote Exploration Operations

    Science.gov (United States)

    Schreckenghost, Debra; Fong, Terrence; Milam, Tod; Pacis, Estrellina; Utz, Hans

    2009-01-01

    To ensure that robots are used effectively for exploration missions, it is important to assess their performance during operations. We are investigating the definition and computation of performance metrics for assessing remote robotic operations in real-time. Our approach is to monitor data streams from robots, compute performance metrics, and provide Web-based displays of these metrics for assessing robot performance during operations. We evaluated our approach for measuring robot performance with the K10 rovers from NASA Ames Research Center during a field test at Moses Lake Sand Dunes (WA) in June 2008. In this paper we present the results of evaluating our software for robot performance and discuss our conclusions from this evaluation for future robot operations.

  18. Early carotid endarterectomy performed 2 to 5 days after the onset of neurologic symptoms leads to comparable results to carotid endarterectomy performed at later time points.

    Science.gov (United States)

    Avgerinos, Efthymios D; Farber, Alik; Abou Ali, Adham N; Rybin, Denis; Doros, Gheorghe; Eslami, Mohammad H

    2017-12-01

    Timing of carotid endarterectomy (CEA) after onset of neurologic symptoms remains controversial. We assessed the association of CEA timing with postoperative outcomes. The Vascular Study Group of New England (VSGNE) database (2003-2014) was queried to identify CEA performed for symptomatic carotid stenosis during the same hospitalization. Cases were divided into four groups based on the time from onset of neurologic symptoms to CEA: group I, <2 days; group II, 2 to 5 days; group III, ≥6 days; and group IV, same-day CEA. The χ2 test and t-test were used to compare demographics, medical history, modified Rankin scores, and outcomes (30-day postoperative death, stroke, myocardial infarction, and aggregate events [stroke/myocardial infarction]). Multivariable logistic regression was used to compare the association of time to surgery with outcomes while adjusting for confounding variables. Kaplan-Meier and Cox proportional hazards regression analyses were performed at 1 year to evaluate survival and stroke rates between the groups. There were 989 of 14,864 VSGNE CEA cases that fit the inclusion criteria. The frequency of cases was highest in group II (36.6%), followed by groups I (31.9%), III (18.9%), and IV (12.4%). Age, gender, and comorbidity compositions were similar between groups, although group III had the highest rates of diabetes mellitus, coronary artery disease, coronary artery bypass graft procedures, congestive heart failure, and American Society of Anesthesiologists class 4 and the highest modified Rankin score (P < .05). Stroke rates were highest in group I (7.3%; P = .016), whereas group III had the highest rate of discharges to nursing facilities (37.2%; P < .001); other adverse outcomes were comparable among groups. CEAs in group I had significantly increased adjusted odds of stroke; adverse outcomes of CEAs in groups II and III were comparable to those in group IV. Our results suggest that CEAs performed 2 to 5 days after a neurologic event

  19. Anthropogenic lead dynamics in the terrestrial and marine environment

    Science.gov (United States)

    Reuer, Matthew K.; Weiss, Dominik J.

    2002-12-01

    Human activities have greatly altered the natural geochemical cycles of several heavy metals, most notably lead derived from leaded-petrol and metal-smelting emissions. This inadvertent geochemical tracer experiment poses two challenges: understanding how anthropogenic lead affects human health and the environment, and quantifying its time-dependent distribution within terrestrial and marine systems. Accurate assessment of the latter relies on well-constrained historical and modern lead fluxes from proxy records and direct observations, lead source estimates from stable lead isotopes, and transport rate estimates from radionuclides. Numerous studies support the global-scale atmospheric lead fluxes principally derived from anthropogenic activities, the short lead residence time in the atmosphere and surface ocean, and the predominance of North American and European lead emissions. Emerging observations and models are currently addressing the time-dependent evolution of this reactive tracer in the atmosphere and oceans.

  20. Intelligent Perioperative System: Towards Real-time Big Data Analytics in Surgery Risk Assessment

    OpenAIRE

    Feng, Zheng; Bhat, Rajendra Rana; Yuan, Xiaoyong; Freeman, Daniel; Baslanti, Tezcan; Bihorac, Azra; Li, Xiaolin

    2017-01-01

    Surgery risk assessment is an effective tool for physicians to manage the treatment of patients, but most current research projects fall short in providing a comprehensive platform to evaluate the patients' surgery risk in terms of different complications. The recent evolution of big data analysis techniques makes it possible to develop a real-time platform to dynamically analyze the surgery risk from large-scale patients information. In this paper, we propose the Intelligent Perioperative Sy...